Castor fiber) has been reintroduced successfully in Germany since the 1990s. Since wildlife is an important source of zoonotic infectious diseases, monitoring of invasive and reintroduced species is crucial with respect to the One Health approach. Three Eurasian beavers were found dead in the German federal states of Bavaria, North Rhine–Westphalia and Baden–Wuerttemberg in 2015, 2021 and 2022, respectively. During post-mortem examinations, Corynebacterium (C.) ulcerans could be isolated from the abscesses of two beavers and from the lungs of one of the animals. Identification of the bacterial isolates at the species level was carried out by spectroscopic analysis using MALDI-TOF MS, FT-IR and biochemical profiles and were verified by molecular analysis based on 16-23S internal transcribed spacer (ITS) region sequencing. Molecular characterization of the C. ulcerans isolates using whole-genome sequencing (WGS) revealed a genome size of about 2.5 Mbp and a GC content of 53.4%. Multilocus sequence typing (MLST) analysis classified all three isolates as the sequence type ST-332. A minimum spanning tree (MST) based on cgMLST allelic profiles, including 1211 core genes of the sequenced C. ulcerans isolates, showed that the beaver-derived isolates clearly group on the branch of C. ulcerans with the closest relationship to each other, in close similarity to an isolate from a dog. Antibiotic susceptibility testing revealed resistance to clindamycin and, in one strain, to erythromycin according to EUCAST, while all isolates were susceptible to the other antimicrobials tested.The Eurasian beaver ( Castor fiber) was a missing link in wildlife ecosystems due to its almost complete extinction to a population size of only about 1200 animals in Europe at the beginning of the 20th century [Francisella tularensis [E. coli [Salmonella spp. [Klebsiella pneumoniae [Yersinia enterocolitica [Campylobacter [Leptospira spp. [Staphylococcus aureus [The Eurasian beaver  strains, the diphtheria tox gene-bearing and expressing strains (DT-positive), and non-toxigenic tox-bearing (NTTB) strains [C. ulcerans has evolved into the most important zoonotic Corynebacterium sp. causing diphtheria-like illness in Europe, superseding C. diphtheriae over the last two decades [d humans ,26. Furt strains . Of part decades ,28,29,30C. ulcerans in Eurasian beavers in Germany for the first time. These case reports are of special relevance, because the C. ulcerans isolates can lead to fatal infections in beavers and render those isolates as potential zoonotic agents.In this study, we present three temporally and geographically independent cases of infections with pathogenic In general, all beavers that are found dead are sent to post-mortem examination for a passive wildlife health monitoring. An active health monitoring of beavers is not possible because beavers are strictly protected species and hunting, capturing and taking beavers from their natural habitat is strictly prohibited.The first beaver (Beaver 1) was found dead in the county of Main–Spessart in the federal state of Bavaria, Germany on 21 September 2015 and was submitted to LHL Giessen for post-mortem and microbiological examinations on the same day.The second beaver (Beaver 2) was found moribund at Wilhelmsruh on the Hevel in the county of Soest in the federal state of North Rhine–Westphalia, Germany on 7 April 2021. It was submitted to a local veterinarian and died two days later in the veterinary practice. Post-mortem and microbiological examinations were carried out at CVUA Westfalen in Arnsberg on 9 April 2021.The third beaver (Beaver 3) was detected dead in the urban district of Heilbronn in the federal state of Baden–Wuerttemberg, Germany on 8 June 2022 and was submitted the next day to CVUA Stuttgart for post-mortem and microbiological investigations.The lungs, liver, spleen, kidneys, and the small and large intestines of the beavers were submitted to bacteriological examinations. Aseptic cut surfaces of the organs were directly streaked onto the surface of sheep blood agar and selective MacConkey or Gassner agar (intestines), and subsequently incubated at 37 °C under atmospheric conditions for two days. In addition, all abscesses were sampled and material streaked on sheep blood agar and selective MacConkey agar. Grown colonies were taken directly from the agar plates and pure cultures were prepared for identification and characterization.Corynebacterium cultures were identified at the species level by MALDI-TOF MS  using an extended reference database [database . The isodatabase .® ID System  according to the manufacturer’s instructions. The type strain C. ulcerans DSM 46325T (NCTC 7910T) was used for quality control and reference.Metabolic profiles were created using the GEN III OmniLogC. ulcerans isolates at right angles to a centrally growing Staphylococcus (S.) aureus (WDCM 00034) and Rhodococcus (R.) equi (ATCC 33701) by typical inhibition of the staphylococcal and enhancement of the rhodococcal hemolysis, respectively [Phospholipase D activity was detected by streaking the qui ATCC 701 by tyrpoB-gene according to the recommendations of Khamis et al. [Corynebacterium spp. In addition, sequencing of the 16-23S internal transcribed spacer region (16-23S ITS) was performed using modified broad-range primers based on sequences provided by Johnson et al. [In addition, these results were verified by partial sequencing of the s et al. , using tn et al.  and Huntn et al. : 1522F_mn et al. .Detection of the diphtheria toxin gene was performed by real-time PCR , and toxC. ulcerans isolates was performed by the broth microdilution method for determination of minimum inhibitory concentrations (MIC) to 14 different antimicrobials. The tests were carried out in commercially available antimicrobial microdilution plates for companion animals following the manufacturer’s instructions  research group on antimicrobial resistance). The following 14 antimicrobials were tested (ranges given in mg/L): amoxicillin/clavulanic acid (0.063/0.031–16/8), ampicillin (0.125–8), cefovecin (0.25–4), cephalexin (0.5–16), chloramphenicol (1–16), clindamycin (0.031–1), enrofloxacin (0.016–2), erythromycin (0.023–4), gentamicin (0.063–4), oxacillin (0.063–2), penicillin G (0.063–4), pradofloxacin (0.004–1), tetracycline (0.063–8) and trimethoprim/sulfamethoxazole (0.25/4.75–2/38). Results  of the antimicrobial susceptibility testing were interpreted using clinical breakpoints according to EUCAST [C. ulcerans DSM 46325T (NCTC 7910T) was used for quality control and reference.Antimicrobial susceptibility testing of the o EUCAST  for brotWGS of the three isolates was performed with Illumina paired-end sequencing  after DNA isolation using the Promega Maxwell system and library preparation with the Illumina DNA prep kit. WGS read data were checked for quality and absence of contamination with Illumina SAV software, fastqc  and krakC. diphtheriae NCTC 11397T, C. belfantii FRC0043T, C. rouxii FRC0190T, C. pseudotuberculosis DSM 20689T (ATCC 19410T), C. silvaticum DSM 109166T , C. ulcerans DSM 46325 T (NCTC 7910T) and C. epidermidicanis DSM 45586T, as a closely related outgroup of the C. diphtheriae group.For genetic species confirmation, genomes were trimmed  and asseatpA, dnaE, dnaK, fusA, leuA, odhA, rpoB described in [C. ulcerans isolates, ignoring missing alleles during the pairwise profile comparisons and using two different ad hoc typing schemes:Multi-locus sequence typing (MLST) and core genome (cg) MLST were performed in Ridom SeqSphere+ . MLST was conducted based on the seven genes ribed in ,47. Mini(1)C. ulcerans/C. pseudotuberculosis scheme with 193 species-overlapping target loci, as previously described in [C. pseudotuberculosis and C. silvaticum enables differentiation of the most closely related species.A pan-genomic ribed in . The add(2)C. ulcerans cgMLST scheme of 1211 target loci, previously described by Berger et al. [C. ulcerans isolate typing profiles.A r et al. , with thThe beaver was a young male  with a remaining body weight of 1.0 kg. The animal was cachectic and showed low-grade autolysis. Post-mortem examination of the inner organs revealed no special findings. Abscesses could not be found.C. ulcerans (151012433-002) and Staphylococcus aureus in the lungs and a low growth (about 10 colonies) of Yersinia enterocolitica in the colon.Bacteriological examination revealed a moderate growth (about 100 colonies) of The cause of the cachexia and death of this animal could not be identified.Emmonsia crescens. Bacteriological testing showed severe growth (about 1000 colonies) of Streptococcus (S.) castoreus in the lungs, liver and abscess, accompanied by moderate growth (about 100 colonies) of C. ulcerans (S 477/6/21). The age, the bite wounds and the infections of the animal are to be considered as the cause of cachexia and death.The second beaver was an old female with a body weight of 13.6 kg. This animal was also cachectic with atrophy of the coronary fat and pronounced edema were detected in the subcutaneous tissue of the ventral thoracic region and abdomen. Furthermore, post-mortem also revealed swollen lymph nodes and scars in the throat region. An abscess was detected in the subcutis in the region of the left hip and a further abscess at the third left rib fused with the left lung . Swab saEmmonsia crescens). Bacteriological examinations showed severe growth (about 1000 colonies) of C. ulcerans (CVUAS 33950), accompanied by a moderate growth (about 100 colonies) of S. castoreus in the specimens taken from the abscesses. The injuries and the infections are considered the cause of the cachexia and subsequent death of the beaver.The third beaver was a young male with a body weight of 16 kg. The nutritional condition of the beaver was poor, resulting in a loss of the coronary fat. The external examination of the body revealed previous injuries in the throat area and multiple abscesses in the lymph nodes localized in the inguinal region and on the cranial upper jaw. Swab samples from the lymph node abscesses and the inguinal region were taken for bacteriological examination. Black colored stipples in the tissue were verified by histo-pathological examinations as multiple granuloma-enclosing conidia that are typical of adiaspiromycosis   and FT-IR spectroscopy . Evaluation of the partial rpoB gene sequences using NCBI BLAST revealed high similarity between C. ulcerans and C. silvaticum . However, a differentiation from C. pseudotuberculosis was unequivocal .The three troscopy , as wellC. ulcerans isolates from the beavers produced phospholipase D. This could be demonstrated on sheep blood agar by inhibition of the hemolysis of S. aureus and a synergistic hemolysis with R. equi. These C. ulcerans isolates are classified as toxigenic since they carry and express the diphtheria toxin gene.All of the three C. ulcerans DSM 46325T (NCTC 7910T) was used. Differences in biochemical reactions between the beaver isolates and the reference strain become apparent. Despite not all members of the C. diphtheriae group having been included in the Omnilog database, the three C. ulcerans isolates and the reference strain C. ulcerans DSM 46325T (NCTC 7910T) were clearly identified at the species level by the Omnilog software, with a distance value of ≥0.500 (DIST 5.439–5.597).A broad analysis of biochemical identification properties was assessed for the three isolates under study, for which results are shown in C. ulcerans DSM 46325T (NCTC 7910T)  .T (NCTC 7910T).The results of antimicrobial susceptibility testing are listed in T (NCTC 7910T) was susceptible.However, when using the newly recommended EUCAST breakpoints for erythromycin (MIC > 0.06 mg/L), only isolate S 477/6/21 (Beaver 2) displayed a resistant phenotype (0.064 mg/L) , while tC. ulcerans isolates and the resulting data were used for confirmation of the genetic species by ANI and for phylogenetic clustering by cgMLST, using two different schemes. ANI analysis in comparison with type strain genomes from the C. diphtheriae group confirmed the results of the MALDI-TOF MS, FT-IR and 16-23S ITS analyses. The three isolates were clearly classified as C. ulcerans, with ANI values of 98% compared with the C. ulcerans-type strain. These ANI values are above the threshold value of ~95–96% for taxonomic delineation of prokaryotic species [WGS was carried out on the three  species , whereasC. ulcerans sequence type (ST)- 332 .MLST analysis based on seven housekeeping loci classified all three isolates as C. ulcerans and C. pseudotuberculosis were used. These divide in the resulting species-specific MST branches, with the beavers’ isolates grouping in the branch of the species C. ulcerans but being separate in different branches from C. pseudotuberculosis, as well as from the closely related C. silvaticum. For comparison, genomic profiles from other animal-derived isolates of the three species, generated with the same scheme, were included in the analysis. The beaver-derived isolates clearly group on the branch of C. ulcerans  of 14–26 and to the nearest relative C. ulcerans from another host species derived from a dog quantified with an AD of 86 ) [Corynebacterium spp. in this study.The quality of MALDI-TOF MS results strongly relies on comprehensive and sophisticated databases representing all currently established ae group ,31. Thisae group ,31,52,62nsidered . This Coulcerans ,31. In oe 2022)) . Using ee 2022)) ,31,69. Ttox gene, and production of the diphtheria toxin were verified for all three C. ulcerans isolates as recommended [C. ulcerans isolates [C. diphtheria and in 50–60% of the C. ulcerans isolates [C. ulcerans in wild and exotic animal species have already been found in otters [Production of virulence factors, e.g., phospholipase D (PLD), presence of the ommended ,62. Wherisolates ,52, prodisolates ,70, was isolates . A recenisolates . Strainsn otters , water rn otters  and hedgn otters ,32. ThesC. ulcerans, S. castoreus was isolated in abscesses from two animals and also, in one of these animals, in the liver and lungs. S. castoreus has been described as a separate, beta-hemolytic Streptococcus sp. belonging to the group A streptococci, which have previously been isolated from multiple bite wounds in a beaver [S. castoreus exclusively in beavers, considering that this Streptococcus sp. is strictly host-specific [S. castoreus has also been isolated from suppurative lesions in association with bite wounds and systemic infections, as well as from apparently healthy beavers. However, S. castoreus has been assessed as being an opportunistic pathogen in beavers, primarily colonizing the normal microbiota of the oral, respiratory and genital mucosa. Finally, tissue lesions and concomitant colonization by opportunistic pathogenic bacteria such as Actinomyces, Corynebacterium or streptococci and Gram-negative obligate anaerobic bacteria might lead to severe poly-microbial suppurative inflammation and abscesses [In addition to a beaver . There aspecific ,74. In tbscesses ,76,77.Overall, the number of beavers that are available for mircobiological investigations is very limited because impairment of beavers in their natural habitat is strictly prohibited. Thus, active monitoring on the health of beavers is not realizable, meaning that data are available from only a limited number of free-ranging beavers found dead. In the federal states of Hesse and Baden–Wuerttemberg, 17 and 115 animals have been subjected to post-mortem examinations in the last 10 years, respectively. However, in the federal state of North Rhine–Westphalia, this was the first beaver examined by post-mortem analysis.C. ulcerans isolates from the three beavers revealed a genome size of approximately 2.5 Mbp and a GC content of 53.4%. This data is consistent with that previously reported for C. ulcerans isolates originating from animals and humans [C. ulcerans, which is consistent with MALDI-TOF MS, FT-IR and 16-23S ITS analysis.Whole-genome sequencing has become a valuable tool for the molecular characterization of bacterial isolates as a basis of molecular epidemiology ,79. Evald humans . ANI andC. ulcerans isolates as ST-332. There are only a few reports on this sequence type, detected in hedgehogs [C. ulcerans [C. ulcerans cgMLST analysis using 1211 core genes shows that the genetic distance between the C. ulcerans isolates from the beavers is smaller than that of the isolates from other animal host species. A similar cgMLST scheme in C. diphtheriae with a size range of 1500 alleles showed a comparable range of allelic distances like single nucleotide polymorphism (SNP) phylogenies; closely related isolates of C. diphtheriae and C. ulcerans showed distances of only a few alleles/SNPs, respectively [WGS-derived MLST based on seven housekeeping loci allowed a classification of the beaver edgehogs , in a caedgehogs  and in hedgehogs ,51,81,82ulcerans . A MLST ectively ,70,83. GC. ulcerans in this wild animal species for the first time. Based on WGS data, the isolates show close genetic but no clonal relationship to each other or to isolates originating from other host species. C. ulcerans isolates are known as zoonotic agents. In this respect, these isolates from beavers must be considered as potential zoonotic candidates, and beavers should be recognized as a heretofore unknown possible reservoir for pathogenic C. ulcerans. In order to cover the important and complex group of zoonotic corynebacteria, interdisciplinary cooperation with regard to the One Health approach is pivotal.Wildlife disease surveillance is an important instrument for the early detection of emerging diseases and zoonoses. Therefore, examinations of all wild animals found dead are a vital element of wildlife disease surveillance. In this context, we examined three Eurasian beavers and were able to detect C. ulcerans in wildlife supported by molecular epidemiology should be conducted to obtain deeper knowledge about the occurrence, epidemiology and impact of C. ulcerans in beavers and other semi-aquatic mammals, particularly considering the ever-increasing beaver population in Europe.Further investigations on pathogenic


Pheromones are chemical signals secreted by one individual that can affect the behaviors of other individuals within the same species. Ascaroside is an evolutionarily conserved family of nematode pheromones that play an integral role in the development, lifespan, propagation, and stress response of nematodes. Their general structure comprises the dideoxysugar ascarylose and fatty-acid-like side chains. Ascarosides can vary structurally and functionally according to the lengths of their side chains and how they are derivatized with different moieties. In this review, we mainly describe the chemical structures of ascarosides and their different effects on the development, mating, and aggregation of nematodes, as well as how they are synthesized and regulated. In addition, we discuss their influences on other species in various aspects. This review provides a reference for the functions and structures of ascarosides and enables their better application. Caenorhabditis elegans, whereas some nematodes show parasitic lifestyles, such as root-knot nematodes (RKNs) and cyst nematodes (CNs). The impacts of nematodes extend to various domains of life. Plant parasitic nematodes cause a destructive loss in crop productivity, and, on the contrary, entomopathogenic nematodes can be used to kill insect pests in agriculture . Su. SuC. el/asc-C7)  and ascr/asc-C7)  were alss ascr#2 . A derivs ascr#2 . Ascr#5 s ascr#2 . In addigans L2d . Ascr#5 gans L2d . In ASI pression . Ascr#8  elegans .C. elegans named icas#9   . It can -asc-C5)  also act-asc-C5)  54], bu, buC. elP. pacificus is a model species that has been extensively studied in biology [P. pacificus [P. pacificus exo-metabolome and found that it has rich signaling molecules controlling adult phenotypic plasticity, including ascarosides ascr#1, 9, and 12. Pasc#9  survive as the only state of entomopathogenic nematodes. After IJs infect the host insects, they recover and lay eggs in their adults, which develop through four larval stages (J1–J4) to form the next generation [H. bacteriophora secretes the ascaroside C11 ethanolamine (asc C11 EA)  , which pmilarity .Bombyx mori) [Mate selection is universal in sexually reproducing organisms, and pheromones provide individuals with advantageous mating information that helps them to select high-quality mates. In the twentieth century, the first sex pheromone was named bombykol, which is released from female silk moths (yx mori) . Sex pheyx mori) . These pyx mori) . GeneralC. elegans mainly reproduces as a hermaphrodite. However, most Caenorhabditis worm species achieve this by means of cross-fertilization. These hermaphrodites are essentially females with the ability to self-fertilize, and they can also mate with males, but their numbers are typically relatively low. Hermaphrodites do not appear to be attracted to male C. elegans, but males are attracted to them [C. elegans males but repels hermaphrodites and can increase the lifespan of C. elegans. Ascr#8 is a strong male-specific attractant and shows synergy with ascr#2 and ascr#3. A mixture composed of ascr#3 and ascr#8 strongly attracts males at ultra-low concentrations, but at higher concentrations, it is repulsive to hermaphrodites [C. elegans. Ascr#3 has an α, β-unsaturated fatty acid moiety, whereas ascr#10 has the corresponding dihydro-derivative; such minor structural modifications deeply influence their signaling properties. The male pheromone ascr#10 strongly attracts hermaphrodite nematodes and shortens their lifespan [Caenorhabditis species. Icas#2 and icas#6.2 . It has been shown that both sexes of B. xylophilus produce sex pheromones: unmated females attract conspecific males, and males attract both mated and unmated females through volatile chemical compounds. Additionally, Bursaphelenchus okinawaensis, which is associated with insect vectors and host plants, produces a pheromone that attracts males [ts males ,87. HoweGlobodera rostochiensis. Hermaphrodites attract males for mating by producing pheromones. Four fractions of the homospecific sex pheromone produced by virgin females, which were isolated using chromatography technology, were tested for their ability to attract male G. rostochiensis; only two of the fractions showed sex pheromone activity. Several weakly basic polar compounds constitute the sex pheromone of G. rostochiensis. The exact structure of its components is unclear [The dimorphism of the adults is an important feature of the life history of  unclear .The chemical structure diagram for sex pheromones secreted by nematodes is shown in C. elegans uses specifically modified forms of the ascarosides that contain indole units as highly effective aggregation pheromones. The indole ascarosides (ICASs) incorporate an L-tryptophan-derived indole-3-carboxylic acid group, which is linked to the four-position of the ascarylose moiety. An indole carboxy unit forms one indole derivative, and it is connected to an ascarylose bearing a nine-carbon unsaturated side chain identical to that found in the known ascr#3; this indole carboxy ascaroside is called “icas#3” , more effectively so than icas#3 and icas#9 [C. elegans adults; however, more in-depth research is needed on this topic [“icas#3” . The icad ascr#3 ,89. Icasd ascr#3 . The 4-hd icas#9 . Ascr#5 is topic .See C. elegans can specifically produce certain octopamine ascarosides, in which the ascarylose four-position is linked to a side chain derived from the succinylation of the neurotransmitter octopamine. The octopamine ascarosides osas#2  when searching for bacterial food [C. elegans. Different strains of C. elegans have different sensitivities to icas#9 due to differences in the expression of the srx-43 gene, which encodes the icas#9 receptor [C. elegans can also develop certain memory behaviors in response to pheromones such as ascr#3, ascr#5, and icas#9 [ial food . At physreceptor . C. elegd icas#9 ,99,100.Meloidogyne incognita, Meloidogyne javanica, and Meloidogyne hapla, as well as from cyst (H. glycines) and lesion (Pratylenchus brachyurus) nematodes [C. elegans [Research has shown that abundant ascr#18  could beematodes . This co elegans  and ento elegans ,66. AscrC. elegans, which causes the dispersal of nematodes. The pheromone mixture of ascr#9 and ascr#11  and Heterorhabditis spp. , which indicated that ascr#9 may be widely present in dispersal mixtures from entomopathogenic nematodes. However, it was found that ascr#11 is present in some species of Steinernema, but not in Heterorhabditis, indicating that ascr#11 may be specific to Steinernema [H. bacteriophora H06 [Steinernema carpocapsae All and H. bacteriophora H06 in the liquid medium [Entomopathogenic nematode IJs can sense ascaroside mixtures including ascr#2, 3, and 8 and icas#9 from  ascr#11  from coninernema ,104. Aschora H06 , while ad medium .B. xylophilus, the causal agent for pine wilt disease and a global quarantine pest, usually displaces Bursaphelenchus mucronatus, a native sympatric sibling species. Similar to what occurs in C. elegans, in B. xylophilus, the pheromones comprise the hydrophilic ascarosides family, which are derivatives of 3,6-dideoxy-L-saccharose linked to fatty-acid-derived side chains; they regulate the transmission of B. xylophilus and its vector beetle, and they regulate the lifecycle of B. xylophilus [Bxydaf-38 and Bxysrd-10, participate in the perception of ascr#9 [B. xylophilus, though it reduces body length in B. mucronatus [The pinewood nematode, lophilus . Ascr#9 lophilus . Moreovef ascr#9 . When micronatus . C. elegans has shown a tendency to be attracted to a series of odorous substances, and with the passage of time, this tendency changes from attraction to dispersal [ispersal ,99. Thisispersal . Howeverispersal . HoweverThe following Nematode pheromones mainly function in an intraspecies manner, but further research has shown that they also function between different species ,112, sucArabidopsis leaves after treatment with ascr#1 and ascr#18. AOS, PR1, PDF1.2, LOX2, and other defense-related genes also increased their expression as a result of ascr#18, which may have contributed to the improved plant defensive responses [Manosalva et al.  found thesponses .The typical pine wilt disease encompasses complex associations between PWN, symbiotic fungi, and vector beetles. In this system, nematode pheromones not only increase the number of mycelia, and improve the spread of fungi and nematode efficiency , but theArthrobotrys oligospora can form traps of adhesive nets via the stimulation of ascaroside pheromones [Nematode-trapping fungi are predators that can consume nematodes and are widespread in soils of distinct ecological provenances . Nematoderomones ,116,117.Recent studies have revealed that the main components of nematode pheromones, ascarosides, can be widely metabolized by animals, plants, and microorganisms , which mC. elegans can secrete many kinds of ascarosides to improve development and induce dauer formation. Entomopathogenic nematodes can secrete different ascarosides to assist them in finding hosts and thriving. The pheromones secreted by plant parasitic nematodes are even closely related to interspecific competition. The latest research has shown that secreted pheromones can be sensed and even metabolized by organisms in the environment .Pheromones play wide-ranging roles in nematodes, such as in their development, mating, aggregation, olfactory plasticity, and dispersal. These pheromones are closely related to a variety of factors such as lifestyle, sex, and developmental stage, and the nematodes living in various habitats can produce rich and diverse pheromones  118,119119. C. eAscarosides are major components of nematode pheromones; they are highly conserved and species-specific, and the same ascarosides may play different roles among nematodes. In chemical terms, they comprise dideoxysugar ascaryloses linked to different fatty-acid side chains along with derivatives of amino acids, folate, and other primary metabolites. Structural and functional diversity exists due to differences in the lengths of the side chains and the derivatives. The effects of ascarosides on nematodes are not only highly dependent on their chemical structure but are also linked to their concentrations and the synergistic effects that take place between ascarosides ,121.C. elegans ascarosides share some structural similarities. For example, the ascarosides produced by Ascaris suum have long chain structures, similar to those of the ascarosides produced by C. elegans [C. briggsae biosynthesizes ascarosides in a manner similar to C. elegans and also has a related developmental pathway that induces the stress-resistant dauer life stage. Thus, ascarosides may play similar roles in other nematode species compared with C. elegans. Studying the functions of ascarosides could provide a new method for controlling the parasitic nematodes, but they need to be further explored. Moreover, nematode pheromones have effects on other species, but the current study has revealed only the tip of the iceberg of the complex multidirectional communication network mediated by ascarosides. Therefore, it is important to further investigate the responses of other species to ascarosides, particularly regarding pathways and receptors, in order to explain this process.Approximately 200 ascarosides have been discovered and identified from over 20 different nematodes ,42,113.  elegans . Recent C. elegans and other nematodes will be helpful in improving our understanding of various biological processes. Although nematode pheromones are only a small class of compounds to be studied in depth, they will certainly have a major impact on the study of interspecific and intraspecific interactions in nematodes.The discovery of nematode pheromones provides new experimental channels for studying pheromone communication and its evolution, which will have significant value in the biological control of harmful parasitic nematodes and chemical ecology. A systematic description of the structures and functions of the pheromones of


Beauveria bassiana is an entomopathogenic fungus used in agriculture as a biological controller worldwide. Despite being a well-studied organism, there are no genomic studies of B. bassiana isolates from Central American and Caribbean countries. This work characterized the functional potential of eight Neotropical isolates and provided an overview of their genomic characteristics, targeting genes associated with pathogenicity, the production of secondary metabolites, and the identification of CAZYmes as tools for future biotechnological applications. In addition, a comparison between these isolates and reference genomes was performed. Differences were observed according to geographical location and the lineages of the B. bassiana complex to which each isolate belonged. Beauveria, about 25 species have been described, most of which originated in Asia—the species’ center of origin [Beauveria bassiana  Vuill  is a versatile microorganism capable of killing insects, surviving as a saprophyte in soil, and creating symbiotic associations with plants as an endophyte [Beauveria bassiana sensu lato has a worldwide distribution and can infect around 700 insect species [Beauveria has been used in the biological control of numerous agricultural pests [Within f origin . Beauverndophyte ,4. Beauv species , Beauveral pests .B. bassiana has a monophyletic origin [Metarhizium anisopliae (Metschn.) Sorokin [According to phylogenetic studies based on the nuclear ribosomal internal transcribed spacer (ITS) and the elongation factor 1-alpha (TEF1-a) gene, c origin . Within c origin . Howeverc origin . The sam Sorokin .B. bassiana from Europe, Asia, Oceania , and North (USA) and South America (Colombia) available in the GenBank database of the National Center for Biotechnology Information ). More recently, eight additional genomes from Central America and the Caribbean, specifically Costa Rica, Honduras and Puerto Rico, have been added to the database [Currently, there are 17 fully sequenced genomes of database , for a tdatabase .B. bassiana for the biological control of different insect pests [Zabrotes subfasciatus (Boh.) [Galleria mellonella (L.); all remaining isolates were extracted from soil in different agricultural systems [B. bassiana fungal accessions from Central America  and the Caribbean (Puerto Rico). Our results provide new insight for the understanding of the pathogenic capacity of the species and the creation of a possible global metagenome. We have identified interesting genetic elements that potentially contribute to the pathogenicity as well as other interesting enzymes that add value to the understanding of the entomopathogenic activity of B. bassiana. Here, we report fungal isolates from the neotropics and provide an overview of the genomic features targeting pathogenic genes and their secondary metabolism potential. We also provide a comparison between these isolates and the previously characterized reference genomes.Costa Rica has implemented entomopathogenic fungi such as ct pests  since thct pests ,14,15. Ts (Boh.) , while fB. bassiana isolates [The fungal isolation, DNA extraction, library prep and sequencing strategy was previously reported for eight isolates . A simplPrior to the de novo genome assembly, raw Illumina reads were quality-checked using FastQC  and procBeauveria bassiana ARSEF 2860 (gb|ADAH00000000.1) reference. To identify the kmer’s distribution through the genomes and to plot its distribution, Jellyfish v.2.2.10 [Genome assemblies were compared and evaluated using Quast v.5.0.2  against v.2.2.10  and Genov.2.2.10  were useB. bassiana genomes: B. bassiana strains ARSEF 2860 (gb|ADAH00000000.1); Bv062 (gb|GCA_003337105.1); B. bassiana JEF-007 (gb|GCA_002871155.1); and B. bassiana HN6 (gb|GCA_014607475.1). To assess the quality and completeness of the assemblies, Quast v.5.0.2 [Due to the short-length nature of Illumina reads and the intrinsic complexity of producing high quality eukaryotic genome assemblies in one go, we implemented the Multi-Draft based Scaffolder (MeDuSa) to optimize the draft assembled genomes scaffolder Medusa v.1.6  against  v.5.0.2  and BUSC v.5.0.2  were useAspergillus oryzae, due to its well-documented necrotrophic lifestyle. In order to identify putative secreted proteins within each fungal isolate, SignalP 4.0 [As a first proteome draft, proteins were predicted by implementing Augustus v2.6.1  trained nalP 4.0  was run B. bassiana isolates [B. bassiana strains ARSEF 2860 (GenBank accession no. ADAH00000000.1); B. bassiana HN6 (GenBank accession no. GCA_014607475.1); and C. militaris CM01 (GenBank ID no. GCA_000225605.1). Single-copy BUSCO genes were identified within each organism and their corresponding proteins were aligned with Multiple Alignment using Fast Fourier Transform (MAFFT) v7.397 [C. militaris CM01 was used [B. bassiana ARSEF 2860 through standard mode parameters.A phylogeny tree was constructed using single-copy BUSCO genes  for all isolates  and refe) v7.397  with the) v7.397 . An autowas used  as the owas used  aided thFor the discovery of the potential biological meaning of the fungal isolates, the BlastKOALA tool was implemented as an automatic annotation server for the genome and metagenome sequences . KEGG orB. bassiana genome annotation for Carbohydrate-Active Enzymes (CAZymes) was performed automatically using the Augustus called-proteins through the dbCAN2 meta server [a server  with thea server  softwareB. bassiana, as there are no entries for entomopathogenic fungi in the PHI-base [B. bassiana isolates and fungal references were identified using homology to characterized MAT genes specific to Clavicipitaceae and Cordyceps sp. using BLASTp. Selected hits fulfill both an e-value of 0.05 or lower and a query coverage filter of at least 55 .To identify the presence of potential virulence-associated genes, blast analysis was conducted against the host–pathogen interactions database (HPIDB 3.0) . The BloPHI-base . Mating-Unprocessed short raw reads were analyzed using Jellyfish and GenomeScope to plot the kmer distribution to check for genome size, heterozygosity rate and repeat content. Globally we observed an optimal genome size, haploidy and low repeat content for all isolates . Aspergillus oryzae dataset, called out 9465 to 10,453 putative proteins. From these, isolates B0, B13, B26 and B27 presented similar counts for potential secreted proteins , strains B1 and B31 had 1028 and 1039, respectively. Similarly, strains B43 and B44 reported 1058 and 1061 ; BbasHN6 (gb|GCA_014607475.1); and C. militaris CM01 (gb|GCA_000225605.1) were included as outputs. This analysis produced a total of 293 core-genes. For each gene, its corresponding BUSCO protein was selected, concatenated and aligned using MAFFT, and an ML tree was inferred using IQ-Tree  were assigned into 10,356 orthogroups. Fifty percent of all genes were assigned in orthogroups with 10 or more genes (G50 was 10) and were contained in the largest 4546 orthogroups (O50 was 4546). There were 7047 orthogroups within all species and 6284 of these consisted entirely of single-copy genes. In addition, there were 1899 unassigned genes accounting for 1.9% of the total number of genes . All isoisolates .To introduce biological information using KEGG categories and the number of gene counts, we focused on specific functional categories . B43 andFrom our analysis, a total of 2349 protein models were assigned to CAZymes distributed into the Auxiliary Activities (AA), Carbohydrate Binding Modules (CBM), Carbohydrate Esterase (CE), Glycoside Hydrolase (GH), Glycosyl Transferase (GT), and Polysaccharide Lyases (PL) families. Most proteins (54%) were associated with the GH family, followed by the GT family (30%) and various other gene families .B. bassiana isolate, we identified 18 putative glycoside hydrolase family 18 (GH18) CAZymes; whereas for the C. militaris CM01 and B. bassiana ARSEF2860 references, we identified 21 genes for each reference. Other important chitinases in the families GH3 and GH16 were absent in our isolates, while for the families GH75 (Chitosan) and GH76, two and nine enzymes were identified, respectively. Furthermore, family GH10 enzymes, present in our isolates, have only been reported in Beauveria bassiana [Cordyceps militaris (L.), Metarhizium anisopliae and Metarhizium acridum (Driver & Milner) J.F. Bisch.), while the GH84 and GH95 families, which were reported previously as exclusive for entomopathogenic fungi [We focused on identifying key members from the GH family, which are involved in the enzymatic deconstruction of chitin  and harbbassiana  and are ic fungi , were obic fungi .C. militaris reported one combination of GH18 + CBM66 , whereas those for Polyketide synthases (PKS) and Terpenes were comparable . All genTo identify the presence of potential virulence-associated genes, a blast analysis was conducted against the Pathogen–Host Interaction database v4.5 (PHIbase). Hits above 70% were the most informative and reliable. We identified PHI genes for important gene families, such as virulence-associated genes, degrading insect cuticles genes, mating-type genes, and core genes for the biosynthesis of secondary metabolites . From thB. bassiana isolate from this study against a database downloaded from the NCBI database specific to the Clavicipitaceae and Cordyceps species. This protein database contained 372 unique entries. We identified seven potential orthologues for each genome respective to the database. Interestingly, each gene was in a single-copy gene orthogroup, except for one orthogroup that lacked a protein for B31, and the genome references B. bassiana ARSEF 2860 and C. militaris CM01; this corresponded to a mating-type protein a-1 (orthogroup OG0009027). On the other hand, the six mating-type candidates had a corresponding single-copy protein in C. militaris, and all homologues showed a high level of conservation  and, at the same time, showed a complete absence of NRPS and PKS compared with the other isolates and reference genomes. In previous analyses, B31 also showed unique alleles in several SSR markers and its lineage could not be determined, while the rest of the isolates were highly diverse but, hence, distinct from Cordyceps [Phylogenetic analyses performed in previous studies determined that all the isolates , except for B27 and B31, belong to an African-Neotropical lineage of bassiana  defined bassiana . In the ordyceps .B. bassiana  and C. militaris (CM01) reference genomes confirmed the singularity of the B31 isolate, whose proteome had a greater similarity to C. militaris than the B. bassiana references and isolates. The direct ancestors of B. bassiana were Asian Cordyceps species, according to Xiao et al. [Beauveria anamorphs and Cordyceps teleomorphs [B. bassiana and the Cordyceps species is the capability of the former to infect a wide host range, while Cordyceps species usually manifest host specificity [Metarhizium species have been shown to evolve from specific-host species to generalist-host species [Beauveria and Cordyceps or a new lineage of the B. bassiana sensu lato complex. New species of Beauveria have been reported in South America [Beauveria species, typically B. bassiana, tends to overshadow the presence of the newly determined species [The Orthofinder ortholog comparison between the fungal isolates and taris CM0 referenceomorphs ,47,48. Ataris CM0 referenc species . This ra America ,51,52 an species ,54.B. bassiana genomes and other entomopathogenic fungi [B. bassiana. In the case of secondary metabolite precursors, the B. bassiana genome contains 45 SM core genes, including 13 NRPS, 12 PKS, 7 NRPS-like, 1 PKS-like, 3 hybrid NRPS-PKS, and 12 genes related to FAS/terpene/steroid biosynthesis [Metarhizium acridum, has been reported by Gao et al. [C. militaris contains enough genes for the infection of specific hosts, while B. bassiana and M. anisopliae are mostly generalist species and have the same NRPSs as the ARSEF2860 reference and fewer PKS components.KEEG analysis of important metabolic pathways, such as the environmental information processing, biosynthesis of secondary metabolites, and lipid and amino acid metabolism, were completed in our genomes. Those pathways are related to the capability of the isolates to develop a pathogenic response and toxin production during the infection process . Previouic fungi , and hero et al. . The reaB. bassiana including one B-type, one C-type and three G-type, and only the C- and G-type showed decreased virulence in topical bioassays [There are no entries for entomopathogenic fungi in the PHI-base , therefoioassays   and other isolates, indicating a possible geographic differentiation. Similarly, continental isolates belonging to different lineages defined by Rehner et al. [Anopheles vectors. Perhaps, due to B31’s association with Costa Rican sugarcane fields, a similar effect is occurring; however, further analysis is needed to investigate this pronounced genetic differentiation.Since allopatric speciation was previously described by Rehner et al.  as an imr et al. , such asr et al. . Accordir et al. , the Bb8Beauveria or other entomopathogenic fungi. Studies from Mexico [Beauveria isolates. Untapped Beauveria diversity in the neotropics through genomics is crucial to develop a comprehensive international landscape of the B. bassiana complex and the different species of the genus. The above, including the finding of Cordyceps ancestor species, is needed to map their evolutionary relationships, host, niche and environmental adaptations.There are still countries, such as Belize, Guatemala, El Salvador, Honduras, Nicaragua, Panama, Dominican Republic, and Haiti, where there are no genomic studies or the molecular characterization of m Mexico ,60, Brazm Mexico  and Costm Mexico ,15,62, h


Helicobacter pylori is considered one of the most prevalent human pathogenic microbes globally. It is the main cause of a number of gastrointestinal ailments, including peptic and duodenal ulcers, and gastric tumors with high mortality rates. Thus, eradication of H. pylori is necessary to prevent gastric cancer. Still, the rise in antibiotic resistance is the most important challenge for eradication strategies. Better consideration of H. pylori virulence factors, pathogenesis, and resistance is required for better eradication rates and, thus, prevention of gastrointestinal malignancy. This article is aimed to show the role of virulence factors of H. pylori. Some are involved in its survival in the harsh environment of the human gastric lumen, and others are related to pathogenesis and the infection process. Furthermore, this work has highlighted the recent advancement in H. pylori treatment, as well as antibiotic resistance as a main challenge in H. pylori eradication. Also, we tried to provide an updated summary of the evolving H. pylori control strategies and the potential alternative drugs to fight this lethal resistant pathogen. Recent studies have focused on evaluating the efficacy of alternative regimens -based triple therapy, high-dose PPI-amoxicillin dual therapy, probiotics augmented triple therapy, or in combination with BQT) in the effective eradication of H. pylori. Thus, innovating new anti-H. pylori drugs and establishing H. pylori databanks are upcoming necessities in the near future. Helicobacter pylori (H. pylori) is a microaerophilic flagellated Gram-negative bacterium with a spiral shape which can switch from spiral to coccoid form. It inhabits the gastric lumen of about half of the human population globally. The helical shape of H. pylori is thought to enable it to survive in the human gastrointestinal tract. Also, the helix shape of H. pylori facilitates bacterial movement, while the coccoid form allows the colonization of the gastric epithelial cells, thus promoting its invasiveness. Moreover, H. pylori is able to form biofilms that lead to antimicrobial resistance, transmutations, and additional troubles with pathogen suppression  based on geographical regions being more remarkable in the developing populations (up to 88%) than in the developed ones  lymphoma and also gastrointestinal carcinoma  adaptation to the gastric acidity, (2) motility and invasion of the gastric epithelial barrier, (3) binding to particular receptors, (4) tissue destruction and other harmful health impacts , neutrophil-activating protein A (NepA), blood group antigen-binding adhesion (BabA), vacuolating cytotoxins (VacA), sialic acid-binding adhesins (SabA), a cytotoxin-associated gene product (CagA), outer membrane vesicles (OMV), outer membrane protein (OMP), and high-temperature requirement A (HtrA) , Helicobacter OMPZ (HopZ) and the H. pylori outer membrane (Hom) family proteins (HomA), HomB, HomC, and HomD. Xu et al. . Besides, other adhesins are involved in the virulence of H. pylori. Recently, Baj et al. , and other proteins. These adhesins interact with the host epithelial cells' receptors. This attachment step protects the invading pathogen from clearance mechanisms, such as gastric peristalsis, constant detaching, and replacement of the mucus layer and the bulk liquid flow. Moreover, it provides nutritional sources to the invading pathogen and enhances the entry of toxins and other effector proteins . Occasionally, OMVs may have extracellular DNA (eDNA). Usually, OMVs are formed in the course of stress responses. OMVs have a crucial role in cell proliferation, viability, and the release of cytokine IL-8. Also, OMVs were demonstrated to promote bacterial survival, bacterial antibiotic resistance, DNA transmission, and stimulation of apoptosis , the fourth class contains iron-regulated OMPs, and the fifth class is made up of the efflux pump OMPs (Oleastro and Ménard Outer membrane vesicles (OMVs) are small, circular structures present on the cell surface of H. pylori virulence, proposing their possible role as vaccine or drug targets. Several OMPs have been reported to take part in the virulence of H. pylori  are involved in Outer membrane porins have a crucial role in adhesion to host cells. The family of outer membrane porin (HOP) adhesion proteins includes several adhesins that adhere to the specific receptors on their host cell membranes. This class consists of the sialic acid-binding adhesin (SabA), blood group antigen-binding adhesin (BabA), HopZ, outer inflammatory proteins A (OipA), HopQ, and the adherence-associated lipoprotein A (AlpA) . Urease has a central role in bacterial metabolism and colonization in the gastric mucus membranes. H. pylori produces two types of urease; one is found in the bacterial cytoplasm , and the other is present on the bacterial surface  (Sharndama and Mba 3) and carbamate. Then carbamate is broken into ammonia and carbonic acid and ultimately promotes the alkalization of the acidic gastric environment; the entire process is controlled by the availability of nickel ions. The full enzymatic action of one urease molecule needs 24 nickel ion cofactors  is a toxin that forms pores in host cells, depending on the exposure time. It enhances bacterial colonization and prolonged existence in the stomach . Adhesion of H. pylori to the epithelial cells of the stomach stimulates cagA expression that is usually associated with high inflammatory responses, damage of gastric mucosal cells, and gastrointestinal injuries provoked by H. pylori (Raghwan and Chowdhury cag pathogenicity island (cagPAI). CagA is inserted into the host cell by pili made by the T4SS  into water (H2O) and molecular oxygen (O2). In general, catalase is a highly expressed protein by H. pylori isolated from the human gastric mucosa. Lekmeechai et al.  is an abundant enzyme in plant and animal cells. KatA acts by converting hydrogen peroxide  has a crucial role in the virulence of H. pylori DNA from any destruction. Thus, NAP supports the survival of H. pylori by its role in DNA protection  family. NAP shows ferroxidase activities devoid of direct attachment, and the entire process produces hydroxyl radicals which have a protective role of H. pylori infection thru disruption of fibrin removal and further impairment of the healing processes. The capability of NAP to stimulate innate inflammatory reactions indicates the pathogenicity of this protein during H. pylori infections thru inducing inflammation of gastric mucosa. In addition to induction of the innate immune responses, HP-NAP also induces adaptive immune responses. During H. pylori infection, NAP induces adaptive immune reactions through induction of T-helper type 1 (Th1) and cytotoxic T lymphocyte (CTL) activities promoting gastritis and tissue injury -1α and MIP-1β. Then, IL-8 further recruits immune cells, including neutrophils, to the infection site. Additionally, NAP stimulates monocytes' secretion of pro-inflammatory cytokines, including tumor necrosis factor-α (TNF-α), IL-12, IL-6, IL-8, and IL-23. Also, it stimulates mast cells to secrete IL-6 and histamine. The secretion of these factors considerably enhances the production of gastrin and pepsinogen and the consequent injury of the gastric mucosa. . SOD enables the dismutation of superoxide to oxygen, avoiding excess toxic superoxide free radicals and supporting the maintenance of homeostasis. In contrast to catalase, H. pylori SOD is found only on cell surface. H. pylori SOD needs iron (Fe) as a cofactor for effective functioning. Any changes in the intracellular iron concentrations affect the SOD activities, making the cell susceptible to oxidative damage (Sharndama and Mba H. pylori SOD prevents cytokines release (thru down-regulation of the nuclear factor kappa B (NF-kB) activation pathway), along with macrophage inflammatory protein 2 (MIP-2), through stimulating macrophage activation  is a virulence enzyme which protects H. pylori has a significant role in the degradation of several lipids, causing bacterial permeability. H. pylori produces phospholipaseA1 (PLA1), phospholipase A2 (PLA2), phospholipase C (PLC) and phospholipase D (PLD), which destroy phosphatidylcholine in addition to phosphatidylethanolamine. This damages the mucus layer and results in progressive impairment of the gastric epithelial cells. Also, phospholipases trigger chronic inflammation, which further induces peptic ulcers. This enhances the colonization and survival of the invading bacteria. Interestingly, H. pylori strains which produce higher quantities of phospholipases, considerably raise the risk of long-term gastritis and consequent gastric malignancies , prevents cell proliferation, and induces apoptosis as well as necrosis of the gastric epithelium through the unwarranted release of inflammatory mediators, including; cyclooxygenase-2 (COX-2), inducible iNOS, IL-8, IL-10, plus the epidermal growth factor-related peptides, causing cell cycle arrest in the G1 phase. Furthermore, GGT enables colonization and survival in the stomach thru modifying immune tolerance via inhibition of T cells and dendritic cell toleration. GGT inhibits CD4+ T cell proliferation, facilitates CD8+ T cells infiltration into the gastric milieu, and inhibits dendritic cells differentiation, activating modifications in their phenotype into the tolerogenic phenotype (Sharndama and Mba Γ-glutamyl-transpeptidase (GGT) is another enzyme produced by H. pylori enzyme that plays a crucial role in the production of cholesteryl α-glucoside (αCGL) thru the addition of α-glucosyl to the host plasma membranes cholesterol. H. pylori can't produce cholesterol by itself. Instead, it extracts cholesterol from the host cell membranes. Then, αCgT activates the glycosylation of cholesterol, yielding cholesteryl glucosides (CGs). It is secreted by H. pylori as an inactive form that is activated by attaching to their host cell membranes. Glucosylation induced by αCgT shields H. pylori from phagocytosis and immunological attack. Furthermore, CGs trigger the release of inflammatory mediators. Also, CGs regulate the CD4+ cells, IL-4 and IFN-γ responses. Moreover, αCgT supports bacterial growth and persistence in the host by disturbing autophagosome–lysosome fusion  is an H. pylori have three main Hsps; HspB (Hsp60), HspA (Hsp10), and Hsp70. HspA plays an essential role in activating the urease enzyme produced by H. pylori during the infection process. Moreover, HspA attaches to nickel ions and bismuth. Accordingly, it might be a prospective target for novel anti-ulcer remedies. Also, the C-terminal domain of HspA has been described to participate in nickel sequestration and detoxification. As nickel is critical for colonization, HspA could be a target for novel H. pylori therapeutics  are a set of proteins which act as molecular chaperones that support maintaining the appropriate structural and functional activities of the cell effector proteins. Also, Hsps controls apoptosis, autophagy, inflammatory responses, and carcinogenesis. Furthermore, Hsps keep bacterial cells from reactive oxygen species (ROS) and oxidative stress  than in the 1990s (3.9%) and 2000s (4.4%). Therefore, the frequency of infected persons might be increasing. Moreover, H. pylori infection, if not eradicated, persists for a lifetime. Several consent reports have been issued in the preceding five years, mainly concentrating on managing H. pylori infections -based triple therapy (PPI and two antibiotics) is one of the most frequently used therapies  is usually suggested when the standard triple therapy fails to give promising outcomes. A ten-day TC-LVF quadruple regimen is the ideal second-line regimen. It comprises esomeprazole (PPI) and bismuth salt, along with antibiotics  has been recommended. DPO-PCR can identify H. pylori infection is dual therapy with amoxicillin and a PPI. The dual therapy has proven encouraging outcomes regarding H. pylori eradication and reducing the concentration of antibiotics used, thus minimizing the effects on the host microbiome , and the extensive use of rifabutin could result in resistant H. pylori strains  significantly enhanced the efficacy. Therefore, rifabutin-based treatments have a perspective as a first- or second-line empiric therapy for Recently, antimicrobial peptides (AMPs) have been confirmed as effective antibiotic alternatives for overcoming resistant microbes , and PGLa-AM1. These are small cationic 5-kDa peptides with a high positive charge and isoelectric point. Although most AMPs are active on some H. pylori antibiotic-resistant strains, several drawbacks to their clinical use, including; their degradation by host and bacterial proteases equally. Some AMPs can produce cytotoxic effects in human cells. Additionally, after prolonged use, bacteria can resist AMPs , and bacteriocins. The anti-H.pylori effects of lactic acid and SCFAs depend on the un-dissociated forms of such organic acids that inhibit H. pylori urease activity and cause cell damage , is the leading light for employing medicinal herbs to fight several infections. Several studies have evaluated the effectiveness of many crude plant extracts in H. pylori treatment. The majority showed weak to moderate activities. However, the extract of Impatiens balsamina L., a Taiwanese folk medical herb, exhibited the highest activity  and Adina pilulifera (AP) is frequently utilized in H. pylori-induced gastritis and peptic ulcers.The application of natural products in C. ambrosioides alone against H. pylori. Besides, Kouticheu Mabeku et al. . Grande et al. .Recently, nanomaterials have been employed to eradicate e et al.  revealedH. pylori biofilms. NAC is a thiol-containing antioxidant which disrupts mucus and is often utilized in the management of chronic respiratory tract infections. Recent research has demonstrated that NAC can inhibit the production of extracellular polysaccharide substrates, inhibit bacterial adhesion, disturb biofilms of different bacteria, and decrease the viability of sequestered cells. NAC pretreatment before initiating triple therapy improved H. pylori eradication rates in refractory H. pylori infections  showed activity against Hathroubi et al. , superoxidase dismutase (SOD), superoxidase dismutase (SOD), neutrophil-activating protein (NAP), catalase (KatA), cytotoxin-associated gene A product (CagA), and outer membrane porins.Latest studies demonstrated that the pathogenesis of H. pylori infection with eradication. Suitable treatment could have promising eradication rates without recurrence of infection. Several recommended regimens exist for eradicating H. pylori. The standard conventional proton pump inhibitor (PPI)-based triple therapy (PPI and two antibiotics) is the most frequently utilized therapy. Also, various second-line treatments can be applied, for instance, BSQ therapy  is usually recommended after the failure of standard triple therapy. Recently, the eradication rates of the standard H. pylori treatment regimens have been declining worldwide. Treatment failure is multifactorial and requires further study. Challenges that face H. pylori management include antibiotic resistance, reinfection, patient compliance to recommended regimens, and treatment adverse effects.Several international guidelines have recommended treating H. pylori. Indeed, H. pylori antibiotic resistance has extended to alarming levels globally. Overuse of antibiotics, changes in the host microbiome, mutations, and incomplete treatment have resulted in alarming antibiotic resistance. Thus, there is a crucial need to find efficient alternatives to combat this global pathogen. Also, the development of H. pylori vaccine is a current research issue. One of the novel approaches is dual therapy with AMX and PPI. Dual therapy has proven encouraging effects in eradicating H. pylori and reducing the concentration of antibiotics used, thus decreasing the adverse effects on gut microbiota. Also, rifabutin-based regimens and AMPs have shown promising potential as efficient alternatives for antibiotics to combat resistant H. pylori infections. Moreover, the administration of probiotics in combination with the eradication regimen resulted in a greater eradication rate, fewer treatment-induced diarrhea, lower adverse effects, better immune responses and greater patient compliance. Besides, recent studies have recommended combining medicinal herbs such as turmeric extract (curcumin) with the standard triple therapy. This considerably ameliorates oxidative stress, decreases DNA damage, improves the histopathological changes in chronic gastritis and increases eradication rates.In fact, antibiotic resistance is the key challenge to the present eradicating regimens of H. pylori proteins whose homologs are lacking in their host and gut microbiome. Some recently identified targets have already been validated and investigated by molecular docking and structural analysis to find novel inhibitors, which will also require validation. Besides, there are several attempts to develop effective drug delivery strategies. Approaches targeting biofilms could be useful in overcoming H. pylori antibiotic resistance. Also, H. pylori proteins of the Dsb system could be possible targets for novel therapeutics. Novel anti-H. pylori treatment strategies and H. pylori databases globally are warranted in the near future.Additionally, various in silico analyses, alongside genomic, metabolomics, and proteomic analysis, have been employed to discover potential novel drug targets, including


Autoimmune hepatitis (AIH) is a chronic liver inflammatory disease with various immune system manifestations, showing a global trend of increased prevalence. AIH is diagnosed through histological abnormalities, clinical manifestations, and biochemical indicators. The biochemical markers involve interfacial hepatitis, transaminase abnormalities, positive autoantibodies, etc. Although AIH pathogenesis is unclear, gene mutations and immunological factors could be the leading factors. AIH usually presents as a chronic liver disease and sometimes as acute hepatitis, making it challenging to distinguish it from drug-related hepatitis due to similar clinical symptoms. Normalizing transaminases and serum IgG levels is essential in assessing the remission status of AIH treatment. Glucocorticoids and azathioprine are the first-line AIH treatment, with lifelong maintenance therapy in some patients. The quality of life and survival can be improved after appropriate treatment. However, certain limitations jeopardize the quality of treatment, including long treatment cycles, side effects, poor patient compliance, and inability to inhibit liver fibrosis and cirrhosis. Accurate AIH animal models will help us understand the pathophysiology of the disease while providing fresh perspectives for avoiding and treating AIH. This review will help us understand AIH better, from the cellular and molecular causes to the clinical features, and will provide insight into new therapy techniques with fewer side effects. This 2AIH causes autoimmune intolerance, resulting in autoimmune cells attacking hepatocytes . However2.1x2 = 8.94, P = 0.011). In addition, there is a synergistic effect between CTLA-4 + 49A/G and DRB1*03:01 on AIH-1 susceptibility [V, was determined to be 0.341, indicating a moderate level of correlation. The bias-corrected Cramer’s V demonstrated a moderate correlation, exhibiting a correlation coefficient of 0.322 [In vivo intervention with recombinant human interleukin-1 receptor antagonist (rhIL-1Ra) can reduce the secretion of TNF-alpha and interleukin-17 (IL-17) and the infiltration of inflammatory cells in the liver thereby inhibiting ConA-induced hepatitis [AIH is a polygenic disease of unknown etiology, and genetic factors can influence the disease progression and clinical phenotype of AIH . AIH pattibility . A recenof 0.322 . The CTLof 0.322 . In addiof 0.322 ,26. Patiof 0.322 . The recof 0.322 . Furtherof 0.322 . A Japanof 0.322 . Inflammof 0.322 . For insof 0.322 . In vivoepatitis . Recentlepatitis ,37,38. Aepatitis . Compareepatitis . The exp2.2in vitro, leading to hepatocyte damage, which was mentioned in the manuscript. LKM1 could be a diagnostic marker for AIH type 2. Cytochrome P4502D6 (CYP2D6) protein can be found on the surface of human liver cells. This cytochrome can be inhibited by LKM1-positive serum in vitro, leading to hepatocyte damage [The liver is constantly exposed to various antigens due to its location and function, indicating the tolerance or responsiveness of the hepatic immune system . Cytokin2.3p < 0.01 [C. leptum in the gut microbiota of AIH patients was also significantly reduced, while the abundance of Escherichia coli was increased [Autoimmune diseases exhibit heterogeneity, manifesting as the involvement of specific or several organ systems. A fundamental association exists between environmental exposures and the likelihood of experiencing adverse health outcomes, wherein the influence on the immune system surpasses genetic abnormalities . Studiesp < 0.01 . In anotp < 0.01 . Upon evp < 0.01 . Intestip < 0.01 . The gutp < 0.01 . Liu et p < 0.01 . The rolp < 0.01 . The abuncreased . After Fncreased . Thus, mncreased . Comparencreased .The drug-induced acute liver failure manifestations could be similar to AIH. Drugs could induce AIH through genetic susceptibility and molecular mimetic mechanisms, depicting the etiology of drug-induced liver injury (DILI) associated with autoimmune features . Minocyc3AIH pathology is diverse and dependents on inflammatory responses of hepatic parenchymal cells due to an autoimmune imbalance . The cha4AIH has an insidious onset and a variety of clinical manifestations, mostly with chronic non-specific symptoms, such as malaise, fatigue, general malaise, etc. Signs such as hepatosplenomegaly and ascites may be present . PatientAIH diagnosis is based on clinical, biochemical, serological, and histological features . The diaAlthough the diagnostic criteria of AIH are relatively clear, its diagnosis is still challenging. To some extent, AIH is still a disease of exclusion, which needs to be differentiated from many similar diseases. In the case of acute hepatitis after infection with acute autochthonous hepatitis E virus, it behaves similar to AIH . In addi5Successful treatment can reduce AIH inflammation and prevent progressive fibrosis while minimizing the therapeutic side effects . The curSince the 1950s and 1960s, prednisone combined with AZA has been the standard of care . Most paBudesonide has a 90% first-pass hepatic clearance, showing a more anti-infective effect than prednisone, with minimal adverse effects . A prospMycophenolate mofetil (MMF) inhibits purine production necessary for the ab initio lymphocyte synthesis during proliferation, thereby reducing inflammatory cytokines and elevating Treg cells. However, MMF has low systemic bioavailability, is teratogenic, and is not advised during pregnancy ,142. SaiCyclosporine and tacrolimus inhibit calcium-regulated neurophosphatase, resisting T-cell activation and cytokine production . Childre6Although there are many treatment options currently available, each of these treatment options has shortcomings that need to be overcome. Therefore, animal models are a better choice for drug development. Besides, it can provide considerable significance for the study of the mechanism of AIH and provide an early basis for further preclinical trials.Animal AIH models are primarily divided into spontaneous  and induced . They provide information about hepatic immunology or cause liver damage mediated by the immune system. Due to their close connection with AIH, these models aid in evaluating novel therapeutic strategies for human diseases. The ideal experimental model should resemble the human condition closely. However, mice mimicking human autoimmune disorders have different autoantigen targets. This is due to class I and II molecule differences in MHC, with specific T-cell responses distinguishing mice from humans . The aniKlebsiella pneumoniae 03:K1 lipopolysaccharide as an adjuvant inside SMA mice. This led to anti hepatocyte-specific lipoprotein antibody production and monocyte infiltration in the liver [The first animal AIH models were developed in the early 1970s when more fundamental immune system mechanisms were discovered. During that time, AIH had a transparent immune-mediated background. Büschenfelde et al. injected liverspecific antigens LP-1 and LP-2 fractions from human liver homogenates into rabbits and various adjuvants. They observed that the large LDL LP-1 effectively induced “experimental immune hepatitis” . LP-1 ishe liver . The modhe liver . S100 exSince the early 1990s, systemic application of Ladin A (ConA) was frequently used to induce liver injury in mice. This activated non-specific T-cell antigens caused acute hepatitis. ConA, a phytohemagglutinin, is a potent mitogen causing cytokine storms. It amplifies through lymphocyte and macrophage interactions, causing inflammation, apoptosis, and liver failure . Furtherin vivo. In the inflammatory process of viral hepatitis, lymphocyte-mediated cytotoxicity is the primary immune mechanism leading to the lysis of virus-infected hepatic parenchymal cells. The adhesion between lymphocytes, antigen-presenting cells, and antigen-producing target cells is essential for the immune response process. The experimental animal model of ConA-induced liver injury in mice is pathologically characterized mainly by activation of T lymphocytes resulting in Acute immune liver injury.ConA is a widely used mitogen that activates T cells and depends on helper T lymphocytes (Th) and macrophages for its effects. ConA activates T lymphocytes and stimulates Th cells and macrophages to produce cytokines such as TNF-α and IFNγ. TNF-α can directly damage hepatocytes and lead to apoptosis. After intravenous injection of ConA into mice, most of it accumulates in the liver, indicating that it is the target organ for ConA toxicity induction The transgenic mice emergence overexpresses specific proteins or lack one or more proteins under system- or organ-specific promoters (KO mice). Many new AIH models have been developed, demonstrating new findings associated with AIH immunopathology. One model is the NTxPD-1−/− mice, where the programmed cell death 1 (PD-1) gene is absent and excised from the thymus . NTxPD-17Most current studies have recognized the role of immune response and tolerance in AIH. Hence, it is imperative to select pharmaceutical agents that exhibit minimal adverse effects on prolonged immunosuppression in the management of AIH. Additionally, exploring potential alternative therapies in cases where the initial treatment fails to provide a satisfactory response is crucial. As previously stated, tacrolimus demonstrates notable efficacy in treating patients with AIH. It may be an alternative therapeutic option for those who exhibit intolerance or experience adverse events to AZA, particularly those who cannot tolerate MMF. However, its current side effects still need to be overcome. Liver-specific autoantigen epitopes recognized by TCRs have not been identified in AIH-1. Autoantibodies and clear autoantigen epitopes of TCRs also enable new options for transgenic animal models and treatments in type 2 AIH. Thus, mechanistic exploration is still essential for AIH-1. Future treatment can start from several aspects based on the current research progress. One area of focus is the advancement of novel immunosuppressants that exhibit enhanced specificity for AIH, thereby effectively managing hepatic damage.Additionally, there is a need to focus on advancing pharmaceutical interventions to reinstate immune regulatory mechanisms and promote antigen-specific tolerance. Furthermore, regulating autoreactive CD4 and CD8 T cell proliferation and elimination is crucial. In conclusion, there is a pressing need to enhance the efficacy of anti-fibrotic medications to mitigate the onset of liver fibrosis or maybe reverse the existing condition. These elements are anticipated to serve as novel therapeutic avenues.8Early diagnosis and treatment of AIH can facilitate good health and reduce the societal burden of chronic diseases. However, there are many unanswered questions in studying AIH mechanisms. These include racial differences, genetic heterogeneity, social environment, and other disease development factors. Therefore, large samples, multicentric and cross-ethnic studies, and developing animal models similar to human AIH can further elucidate AIH pathogenesis. Disease awareness and timely diagnosis are crucial, as untreated disease has a poor prognosis. AIH diagnosis is exclusionary based on various combinations. Diagnosis includes laboratory tests and diagnostic scores, but most are not disease-specific markers, such as autoantibodies, elevated IgG/gamma globulin levels, histological features, and exclusion of other liver diseases. Thus, supplementing diagnostic-specific markers and gaps in high-risk predictors is the requirement. There is still room for improvement in the sensitivity and specificity of current diagnostic methods. To maintain regular testing quality, it is recommended that a quality control system be implemented in the future, employing blind serum testing.Moreover, the current scoring system for AIH fibrosis is mainly derived from viral hepatitis research. Therefore, deepening the recent AIH research is expected to establish a unified histological scoring system to quantify AIH fibrosis in the future. AIH patients face significant unmet clinical needs, and treating those who are intolerant or refractory to standard therapy is challenging. Future treatments should differentiate AIH from other autoimmune diseases, focusing precisely on AIH pathways to define more specific therapies. In parallel, more descriptions of the pathogenesis of AIH should be documented to address treatment options further. Aberrant immune regulatory pathways, epigenetic genome, and intestinal microecology are essential therapeutic targets to alter AIH treatment based on an increasing understanding of disease pathogenesis. The treatment of AIH will be able to achieve the effect of removing pathogenic autoimmune cells while retaining autoprotective immunity. In order to attain this objective, it is imperative to thoroughly investigate the existing body of research about the underlying mechanism of AIH. By adopting this approach, we can better understand genetics, facilitating the implementation of genuinely personalized medical interventions. A comprehensive comprehension of triggers, immunopathogenic mechanisms, and effector processes can promote the advancement of improved and more diagnostic experimental approaches and the formulation of novel therapeutic strategies. Eventually, the tolerance of liver autoantigens will be restored, thereby changing our current treatment plan, providing patients with a better quality of life, and prolonging the prognosis of patients.


Bemisia tabaci is a major agricultural pest with a wide host range throughout the world. The species designation for B. tabaci includes numerous distinct cryptic species or biotypes. Two invasive B. tabaci biotypes, MEAM1 (B) and MED (Q), were found in China at the end of the 20th century and at the beginning of the 21st century. MEAM1 (B) and MED (Q) show higher pesticide resistance levels than native strains, and the levels of resistance vary with changes in insecticide selection pressure. Recent studies have revealed metabolic resistance mechanisms and target site mutations in invasive B. tabaci strains that render them resistant to a range of insecticides and have uncovered the frequency of these resistance-related mutations in B. tabaci populations in China. Novel pest control agents, such as RNA-based pesticides and nano-pesticides, have achieved effective control effects in the laboratory and are expected to be applied for field control of B. tabaci in the future. In this review, we discuss the mechanisms of resistance developed by these invasive B. tabaci populations since their invasion into China. We also provide suggestions for ecologically sound and efficient B. tabaci control.The sweet potato whitefly  B. tabaci is an insect pest that causes serious agricultural and economic losses throughout the world ) and Q (Mediterranean [MED]) are by far the most widespread [The sweet potato whitefly he world . This pedespread .B. tabaci has been recorded as causing damage in China since 1949 [B. tabaci in China attracted the attention of researchers, and the populations involved were identified in 2002 as the biotype MEAM1 (B). This identification was accomplished by sequencing a fragment of the mitochondrial cytochrome oxidase I gene (mtCOI) [nce 1949 , but incAt the beginning of the 21st century, MED (Q) was first detected in Henan Province and Beijing using the same mtCOI sequencing method . Since tB. tabaci biotypes to replace local populations; MEAM1 (B) first displaced non-B populations over a short time period, then MED (Q) rapidly spread to almost all provinces and cities in China and established population dominance [This process involved two sequential rapid invasions of novel ominance ,11. The ominance . MEAM1  were 336 and 441 mg/L for dichlorvos and carbosulfan, respectively [Organophosphorus and carbamate insecticides were released in the 1950s. They are acetylcholinesterase inhibitors that have been applied for many years in China to control multiple pests. sticides . In genesticides . In 2006riegatum . MED (Q)ectively . In compectively ,18. HoweB. tabaci exert resistance to OPs [Ace1, a point mutation in an ace1-type acetylcholinesterase, was shown to be responsible for OP resistance in B. tabaci in Israel [Ace1 mutation (F331W) that was associated with OP resistance revealed that all analyzed samples were homozygous for the mutation, indicating that the F331W mutation was fixed in wild whitefly populations across China [Target site insensitivity and detoxification enzyme activity are the major mechanisms by which e to OPs . Esterase to OPs . An F392n Israel . Howevern Israel . An invess China .B. tabaci [Pyrethroid insecticides were released in the late 1960s. They were gradually but widely adopted due to their higher toxicity and lower required dosages compared to the older generation of organophosphorus insecticides. At the beginning of the MEAM1 (B) invasion into China, this biotype showed high resistance to pyrethroids, with resistance levels up to 1000-fold higher compared to the local populations . Most in. tabaci .B. tabaci control. Buprofezin is a chitin biosynthesis inhibitor, whereas pyriproxyfen is an analog of juvenile whitefly hormone. Invasive B. tabaci in China has developed a range of resistance levels to pyriproxyfen. MEAM1 (B) sampled from Xinjiang in 2004–2005 showed a pyriproxyfen resistance factor (RF) of 22–37 (LC50 = 0.022–0.037 mg/L), although this pesticide had not been in routine use in Chinese agriculture at that time [50 value of 1461 mg/L in lab-raised MEAM1 (B) adults descended from individuals collected in Beijing in 2000; the LC50 value was 8832 mg/L for lab-raised MED (Q) adults descended from individuals collected in Beijing in 2009, demonstrating a significant increase in resistance [Buprofezin and pyriproxyfen are IGRs that have long been used for sistance . Furthersistance . MED (Q)sistance ,26.B. tabaci control in the field for many years. This class of pesticides can be divided into four categories based on their chemical structure: chloronicotinyls, thianicotinyls, nitroguanidines, and sulfoximines  and MED (Q) than in the local Cv populations [B. tabaci has high fitness costs, as demonstrated by the lower intrinsic rate of increase, gross reproductive rate, and net reproductive rate [Neonicotinoids have played a key role in oximines . Neonicoulations . In a laive rate . Field Mive rate . In 2019ive rate . Flupyraive rate .S-transferase (GST) s2 and d7 proteins (GSTs2 and GSTd7) [B. tabaci populations to imidacloprid, thiamethoxam, acetamiprid, and pymetrozine [B. tabaci strain were markedly higher than those in a susceptible strain, and decreases in CYP6CX4 and GSTs2 expression resulted in a significant increase in mortality rate in response to flupyradifurone treatment [B. tabaci resistance to thiamethoxam. A T206A mutation in the 5′ untranslated region (UTR) enhanced CYP4C64 expression in thiamethoxam-resistant strains [B. tabaci strains [B. tabaci resistance to neonicotinoid insecticides may be a combined result of the activities of multiple detoxification enzymes rather than a single enzyme.Detoxification enzyme activity is a major mechanism of resistance to neonicotinoids. P450 monooxygenase plays a key role in the regulation of resistance; it shows significantly higher activity in neonicotinoid-resistant strains and is overexpressed in response to neonicotinoid stimulation ,32. Of td GSTd7) ,34,35,36etrozine ,28. CYP6etrozine . Reducin strains . The exp strains ,39, indiStreptomyces; the avermectin compound abamectin is widely used across China and remains an effective pesticide for B. tabaci control in most regions [B. tabaci MEAM1 (B) and MED (Q). Continuous selection in the laboratory revealed that the development of abamectin resistance in B. tabaci was relatively slow [B. tabaci in China. However, although abamectin resistance development is slow, the risk of increased resistance should still be addressed. Another new biogenic insecticide, afidopyropen, is a semi-synthetic derivative of pyripyropene A, a fermentation product of Aspergillus fumigatus Fresenius . Because it is an insecticide that has been used for a relatively short time in China, afidopyropen has been proven to have high toxicity against B. tabaci MEAM1 (B) and MED (Q) in all field populations tested [B. tabaci is expected to rapidly develop resistance to afidopyropen when exposed to this insecticide within several generations.Avermectins are a class of antibiotic insecticides produced as specialized metabolites by  regions . For manely slow . Until 2ely slow ,14,23,25ely slow . Furtherely slow . Field sely slow ,15,41. Is tested . Resistas tested . Thus, iB. tabaci to these insecticides. In an abamectin-resistant MEAM1 (B) strain, the oxidase inhibitor piperonyl butoxide (PBO) and the GST inhibitor diethyl maleate (DEM) produce significant synergistic effects on abamectin, indicating that enhanced metabolism mediated by P450 monooxygenase and GST activity, but not esterase activity, may be involved in abamectin resistance [The enhanced metabolic detoxification systems found in insects may be the main reason for the observed resistance of sistance . In an asistance .B. tabaci populations [Cyantraniliprole is a second-generation anthranilic diamide product that provides cross-spectrum control of chewing and sucking insect pests. From 2012 to 2016, field populations collected from several regions in China showed little to no cyantraniliprole resistance ,25. Howeulations .B. tabaci strain showed obvious cross-resistance to the abamectin analogue, emamectin benzoate, and to imidacloprid, but not to fipronil [B. tabaci, even though these pesticides target the transient receptor potential vanilloid (TRPV) channel of insects, suggesting that afidopyropen may more effectively target the TRPV channel [As mentioned above, insecticide resistance occurs via two distinct mechanisms: target-site point mutations and increased detoxification effects . Insectifipronil . Elevatefipronil ,39. An ifipronil . Howeverfipronil . A flupyfipronil . This sufipronil . A pymetfipronil . There w channel . Further channel .B. tabaci resistance increases at different rates, depending on the pesticide. In the absence of a pesticide, resistance declines rapidly [B. tabaci generation time ranges from 24 to 30 d; insecticides with different modes of action must, therefore, be rotated for field application every 30 d. All applications should strictly follow the relevant product label with regard to the rate, target pest, and the application method and frequency.Rotating insecticides is the most effective method to delay the evolution of insecticide resistance and to regain pest susceptibility as part of an insecticide resistance management (IRM) program. Under pesticide selection pressure,  rapidly ,43. SeleThe development of insecticide resistance in pests is closely related to long-term and large-scale pesticide application ,11. The B. tabaci field populations to varying degrees [B. tabaci, GST activity is significantly inhibited in vivo by DEM [Enzyme inhibitors may improve pesticide sensitivity in  degrees . Three co by DEM . Rationao by DEM ,38,43,44o by DEM ,38.B. tabaci harbors the primary (P-) endosymbiont, Candidatus Portiera aleyrodidarum , in bacteriocytes. Seven S-endosymbionts have also been identified to date, namely Hamiltonella (Enterobacteriaceae), Arsenophonus (Enterobacteriaceae), Wolbachia , Rickettsia , Cardinium (Bacteroidetes), Fritschea , and Hemipteriphilus (Proteobacteria) [B. tabaci; however, the relevance of endosymbionts to pesticide resistance appears to vary between B. tabaci populations and to be dependent on the insecticide used [B. tabaci endosymbionts participate in the regulation of host pesticide resistance remains unclear, studies of similar systems have revealed relevant mechanisms in Riptortus pedestris [Bactrocera dorsalis [Nilaparvata lugens [B. tabaci insecticide resistance by regulating symbiotic bacteria, thereby providing novel strategies for managing B. tabaci resistance.Symbionts are ubiquitous in insects. Some participate in the synthesis of essential amino acids, forming a stable symbiotic relationship with the host . The symacteria) . Severalide used ,56. Althedestris , Bactrocdorsalis , and Nila lugens . Future B. tabaci control; RNAi of BtTPS1 and BtTPS2 significantly increased mortality and influenced the expression of target genes involved in energy metabolism and chitin biosynthesis in adults [B. tabaci MED (Q), and several other NRs are potential targets for this pest control method due to their important roles in insect development [Iav) together with Nanchung (Nan), a component of TRPV channel, increases MED (Q) sensitivity to afidopyropen [In recent years, pest control strategies based on RNA interference (RNAi) have been rapidly developed. RNA molecules used to control pests are called RNA-based pesticides; such RNAi agents can be used to inhibit or control agricultural pests by silencing the expression of important pest genes. RNA-based pesticides are single- or double-stranded polynucleotide segments that bind specific mRNAs corresponding to the target genes within a pest, causing transcript degradation or translation inhibition . This inn adults . Nuclearelopment . Additioelopment . Furtheropyropen . Althougopyropen . DespiteAt present, most pesticides in China are emulsifiable concentrates and wettable powders that have poor water dispersion, low biological activity, and low effective utilization . The pooB. tabaci biotypes, MEAM1 (B) and MED (Q), have rapidly spread in China. The speed of their spread is considered to be closely related to fitness costs, insecticide resistance, viral vector capacity, and host plant adaptation range. Chemical insecticides have served as the main method for controlling B. tabaci populations for many years, and they will likely remain so in the near future. Controlling the development and spread of pesticide resistance and improving insecticide efficiency will, therefore, be critical aspects of B. tabaci control in the future. MEAM1 (B) and MED (Q) populations had varying degrees of resistance to numerous traditional insecticides at the onset of their invasion of China. They have gradually developed additional resistance to new pesticides as such compounds are made available and applied in the field. Research into the resistance mechanisms used by B. tabaci in China has revealed several mutation sites related to OP and pyrethroid resistance. These mutation sites are now widely found throughout B. tabaci populations in China. Increases in detoxification enzyme activity have been established as key factors underlying most insecticide resistance, such as resistance to neonicotinoids. Insecticide rotation is a critical strategy to manage pesticide resistance. The continuous application of similar insecticides inevitably leads to rapid increases in insecticide resistance; conversely, reducing insecticide selection pressure will rapidly decrease resistance development. Rational use of synergists can also effectively improve pesticide efficiency and reduce the dosage required. Other pest control strategies, such as inhibiting resistance-promoting endosymbionts or using novel pesticides such as RNAi or nano-pesticides, are promising approaches currently in development for effective pest control.Two invasive


The study objective was to identify measles and rubella immunity gaps among people with HIV (PWH) in Zambia despite high measles vaccine coverage and widespread access to antiretroviral therapy.Nationally representative cross-sectional serosurvey using biorepository specimens.Blood specimens collected in the Zambia Population HIV Impact Assessment survey (ZAMPHIA) of 2016 were tested for measles and rubella immunoglobulin G (IgG) antibodies by enzyme immunoassay. Hierarchical generalized additive models were fit to characterize age-specific measles and rubella seroprevalence profiles by HIV infection status. Log-binomial regression was performed to identify factors associated with seronegativity.P < 0.001). Having a detectable viral load was associated with being measles seronegative .Of the 25 383 specimens, a subsample of 11 500 were selected and 9852 (85%) were successfully tested. Measles seroprevalence was lower among PWH compared with HIV-uninfected individuals until approximately 30 years of age. Among children younger than the age of 10 years, measles seroprevalence was 47.2%  in PWH and 76.4%  in HIV-uninfected children in same age category. In contrast, rubella seroprevalence was higher among PWH than HIV-uninfected individuals, particularly for children younger than 10 years (68.6% vs. 44.3%, These results from a nationally representative serosurvey demonstrate persistence of measles immunity gaps among PWH younger than 30 years of age. There is need to implement the World Health Organization's recommendation to revaccinate children living with HIV against measles following immune reconstitution with antiretroviral therapy to protect these children and prevent measles outbreaks. Measles and rubella remain important causes of morbidity and mortality. In 2021, there were an estimated 9.5 million measles cases and 128 000 measles deaths globally ,4. RubelHigh levels of population immunity are needed to interrupt measles virus transmission and even small clusters of susceptible individuals can sustain measles outbreaks . AlthougSeveral systematic reviews found that measles seropositivity was lower among vaccinated children living with HIV compared with HIV-uninfected children –17, consThe studies summarized in the systematic reviews, however, were relatively small, highly heterogenous in study design and laboratory methods, and conducted in specific study populations . No natiThis is the first report of measles and rubella seroprevalence by HIV infection status based on a nationally representative sample and demonstrates persistence of measles immunity gaps among children, adolescents and young adults living with HIV.A nationally representative, cross-sectional measles and rubella serosurvey was conducted by analyzing a subsample of blood specimens collected in the Zambia Population HIV Impact Assessment survey (ZAMPHIA) . ZAMPHIAHIV testing was performed as part of the ZAMPHIA study using two HIV rapid tests, Determine and Unigold . Individ+ T-lymphocyte counts (data on CD4+ T-lymphocyte percentage were not available), HIV-1 viral load, antiretroviral drug use, and recency of HIV-1 infection. HIV viral load suppression was defined as an HIV viral load of less than 1000 copies/ml. Qualitative screening for detectable concentrations of antiretroviral drugs was performed using DBS from HIV-positive children and adults using high-resolution liquid chromatography and tandem mass spectrometry. Efavirenz, atazanavir and lopinavir were selected as indicators of the most prescribed first- and second-line regimens. Specimens from participants with suppressed viral loads or those who self-reported taking antiretroviral drugs but had no evidence of the three indicator drugs were tested for nevirapine. To distinguish recent from long-term HIV infection, two testing algorithms were used: HIV-1 LAg Avidity enzyme immunoassay  with HIV viral load; and HIV-1 LAg Avidity EIA, viral load, and antiretroviral drug detection Specimens with a median normalized optical density of ≤1.5 were classified as potentially representing recent HIV infection and underwent HIV-1 viral load testing for further classification. Specimens with a viral load of <1000 copies/ml were classified as long-term infections whereas those with a viral load of ≥1000 copies/ml were classified as recent infections. In the second algorithm that adjusted for antiretroviral drug use, specimens with a viral load ≥1000 copies/ml and with detectable antiretroviral drugs were classified as long-term infections. Specimens with VL ≥1000 copies/ml and without detectable antiretroviral drugs were classified as recent infections  for PWH and 12 years (IQR: 6–18 years) for HIV-uninfected participants, reflecting the small number of children living with HIV in the study population  than children younger than 15 years (5.4%) (Table Most (97%) PWH did not have evidence of recent HIV infection Table . Of the + T-lymphocyte cell count below 200 cells/μl .Measles seroprevalence increased with age among both PWH and HIV uninfected participants but was lower among children, adolescents, and young adults living with HIV compared with HIV-uninfected participants younger than approximately 30 years of age based on the hierarchical generalized additive model . Only age was significantly associated with rubella seropositivity among PWH in the adjusted model .Among PWH, rubella seroprevalence did not differ significantly between those living in rural (96.0%) or urban (93.8%) settings, those receiving or not receiving antiretroviral therapy, those with recent or past HIV infection, those with CD4This is the first nationally representative measles and rubella serosurvey for which the results were stratified by HIV infection status. Measles immunity gaps were identified among Zambian children, adolescents, and young adults living with HIV despite high measles vaccination coverage and access to antiretroviral therapy. Rubella seroprevalence, reflecting infection and not immunization, was higher among children living with HIV than uninfected children younger than 10 years of age, indicating greater exposure to rubella virus in this age group.The WHO-UNICEF measles vaccine coverage estimates for Zambia in 2021 was 90% for MCV1 (down from 96% in 2020) and 81% for MCV2 (up from 74% in 2020) . HoweverAccording to UNAIDS, approximately 1.5 million people were living with HIV in Zambia in 2020, of whom 83 000 were children . The proThe association between rubella seroprevalence and HIV infection status was different than for measles, with rubella seropositivity higher among children living with HIV than in HIV uninfected children, but similar in older age groups. This difference is because the serosurvey was conducted before the introduction of rubella vaccine in Zambia and thus rubella seroprevalence reflects infection with rubella virus. The higher rubella seroprevalence among children living with HIV may be due to greater exposure to rubella virus in urban settings, as demographic factors such as higher birth rates, increased mobility, and larger population size facilitate rubella virus transmission . A studyThis study had several limitations, most arising from the fact that this was a secondary analysis of specimens in a biorepository collected for another purpose. The original ZAMPHIA survey did not collect information on measles and rubella vaccination status and thus we were unable to assess associations between measles and rubella vaccination and seroprevalence at the individual level, nor could we distinguish vaccine failure from failure to vaccinate. The number of children living with HIV was small, limiting our ability to draw inferences regarding risk factors associated with measles and rubella seroprevalence in this age group. We were unable, for example, to assess whether initiation of antiretroviral therapy before measles vaccination was more likely to result in measles seropositivity after vaccination.These findings highlight the need to implement the WHO recommendation to revaccinate children living with HIV against measles after achieving immune reconstitution with antiretroviral therapy. Consideration also should be given to vaccinating adolescents and young adults living with HIV in communities at risk of measles outbreaks. Policies should be adapted to facilitate tailored strategies to vaccinate older individuals and those in need of revaccination after immune reconstitution.We thank the participants who provided specimens for the ZAMPHIA biorepository. We would also like to thank Lameck Chirwa of the University of Zambia, the CDC Zambia country office, and the Zambia Ministry of Health Directorate of Public Health and Research for authorizing access to the ZAMPHIA biorepository. We thank our colleagues Evans Betha, Samson Mwale, and Shepherd Nehanda at TDRC and Nosiku Sitali, Meikess Kabwe, and Kwalela Kwalela at UNZA for conducting the laboratory testing.Funding: The Bill and Melinda Gates Foundation (Grant # OPP1094816)Author contributions: Conceptualization: S.M., K.H., A.C. and W.J.M.; data collection: S.M., F.D.M., W.J.M., I.C., I.M., G.M., M.M. and K.H., H.N., L.M., G.C.; methodology: S.M., Y.Y., K.H., W.J.M. and A.K.W.; software and analysis: S.M., Y.Y., K.H., A.C. and A.K.W.; writing—original draft preparation: S.M., Y.Y., K.H. and A.K.W.; writing—review and editing: W.J.M., K.H., A.C., A.K.W., F.D.M., I.C., I.M., G.C., M.M., G.M., H.N., L.M., S.M.; visualization: Y.Y. and A.W.; supervision: S.M. and W.J.M.; funding acquisition: W.J.M. and K.H. All other authors critically reviewed results. All authors have read and agreed to the published version of the manuscript. W.M. is responsible for the overall content as a guarantor.smutemb1@jhmi.edu) following publication.Data sharing: Data dictionary will be made available with publication as supplemental material. Study protocol can be made available upon request to the corresponding author (There are no conflicts of interest.