Adrenocorticotropic hormone (ACTH) is produced from proopiomelanocortin, which is predominantly synthetized in the corticotroph and melanotroph cells of the anterior and intermediate lobes of the pituitary gland and the arcuate nucleus of the hypothalamus. Although ACTH clearly has an effect on adrenal homeostasis and maintenance of steroid hormone production, it also has extra-adrenal effects that require further elucidation.We comprehensively reviewed English language articles, regardless of whether they reported the presence or absence of adrenal and extra-adrenal ACTH effects.In the present review, we provide an overview on the current knowledge on adrenal and extra-adrenal effects of ACTH. In the section on adrenal ACTH effects, we focused on corticosteroid rhythmicity and effects on steroidogenesis, mineralocorticoids and adrenal growth. In the section on extra-adrenal effects, we have analyzed the effects of ACTH on the osteoarticular and reproductive systems, adipocytes, immune system, brain and skin. Finally, we focused on adrenal insufficiency.The role of ACTH in maintaining the function of the hypothalamic–pituitary–adrenal axis is well known. Conversely, if we broaden our vision and analyze its role as a potential treatment strategy in other conditions, it will be evident in the literature that researchers seem to have abandoned this aspect in studies conducted several years ago. We believe it is worth re-evaluating the role of ACTH considering its noncanonical effects on the adrenal gland itself and on extra-adrenal organs and tissues; however, this would not have been possible without the recent advances in the pertinent technologies. Adrenocorticotropic hormone (ACTH) was first described in 1933, and after nearly 20 years, it was demonstrated that this polypeptide hormone stimulates adrenocortical activity . After sAfter its cleavage from POMC by PC1/3, ACTH is secreted by mature granules from the anterior lobe of the pituitary gland into the circulation, targeting its receptor on peripheral cells, the melanocortin 2 receptor (MC2R). In addition to MC2R, which is highly specific for ACTH, other melanocortin receptors  can bind to ACTH and other POMC-derived peptides. These receptors are expressed in various tissues  and are Similar to other GPCRs, MC2R activation leads to an increase in intracellular cyclic adenosine monophosphate (cAMP) stimulating the protein kinase A (PKA) signaling pathway . Other iAim of this review is to provide an overview of the effects of ACTH, focusing on the impact of extra-adrenal and non-canonical signaling in health and disease. First, we will briefly summarize evidence on the impact of ACTH signaling on glucocorticoid, mineralocorticoid and androgen secretion, the role in mediating adrenal growth and development and the effects on steroidogenesis and gene expression. Then, we will describe the effects of ACTH on the osteoarticular and reproductive systems, adipocytes, immune system, brain and skin . This pathway, through positive feedback loops, enhances steroid secretion  and thus a considerable cellular oxidative stress. Consequently, several enzymes involved in the detoxification are mobilized in adrenal cells. Aldo–keto reductases participate into this detoxification process, and their expression is ACTH-dependent . Moreovein vitro study showed that ACTH leads to increased cell death through the apoptosis of isolated cells in cultures of the adrenal cortex; however, the zona fasciculata and zona reticularis are more resistant to the cytotoxic and antimitogenic effects of ACTH than zona glomerulosa —which converts norepinephrine to epinephrine—in rats. These alterations were restored upon ACTH injection , 50. Thein vitro  , and results suggested a possible contribution of dysregulated adrenal steroidogenesis in the pathogenesis of hyperandrogenism in PCOS (CTH1-24) . Robust CTH1-24) . MoreoveCTH1-24) . MC2R isCTH1-24) , 78. How in PCOS .in vitro in rodent adipose tissue through MC2R-dependent cAMP/PKA activation  and ACTH with the same affinity, with a dose dependent stimulation of melanogenesis and melanocytes proliferation –114. MCRDisorders of glucocorticoid secretion involve downstream or upstream dysregulation of ACTH secretion or activity. Even though several differences have been described between ACTH-dependent and independent hypercortisolism, chronic adrenal insufficiency (AI) is characterized by prolonged exposure to ACTH excess or defect without increased endogenous glucocorticoids or androgens , providiPrimary adrenal insufficiency (PAI) is characterized by adrenal failure, leading to insufficient cortisol secretion and increased ACTH levels . The incMost genetic causes of HPA axis impairment are rare, and data are obtained by case reports or case series. Defects in ACTH synthesis, receptor, or signaling are among the mechanisms underlying genetic forms of AI. As previously mentioned, resistance to ACTH binding at the adrenal glands can be caused by mutations of the MC2R or MRAP gene and lead to type 1 and type 2 familial glucocorticoid deficiency, respectively. Alterations in ACTH synthesis include syndromes associated with pituitary hypoplasia or aplasia and isolated ACTH deficiency due to the disruption of POMC, PC1, or TPIT, the transcription factor responsible of POMC synthesis in the corticotroph pituitary cells .Generally, the presenting signs and symptoms are hypoglycemia and jaundice due to AI, usually developing during the neonatal period or infancy although the age of onset is variable . FailureIn contrast, in diseases affecting POMC synthesis ACTH levels are low or undetectable, and although these syndromes share AI with those formerly described, they differ under many other aspects. Interestingly, TPIT disruption only affects POMC production from the pituitary gland, whereas other sites of synthesis, such as the skin and hypothalamus, seem preserved ; affecteThe acquired forms of PAI and SAI are more common and better studied than their genetic counterparts. However, data on the contribution of ACTH in establishing the clinical picture and prognosis, aside from adrenal effects and canonical hyper- or hypo-pigmentation, are still limited. In male patients affected by congenital adrenal hyperplasia, prolonged and early exposure to high ACTH levels can lead to the development of testicular adrenal rest tumors , probablThe pleiotropic effects of ACTH are well known. However, its use as a therapeutic agent in the clinical practice is currently limited to selected diseases such as infantile spasms or anti-inflammatory resistant gout, as previously described. In these conditions, especially in infantile spasms in which ACTH treatment is more broadly used, therapeutic effects and treatment-related adverse events largely rely on increased glucocorticoid secretion secondary to ACTH stimulation of the adrenal cortex . Furtherin vitro studies have yielded confounding results on the effects of ACTH on insulin sensitivity and adipose tissue. Given the lack of conclusive data, studies on the possible role for ACTH excess in metabolic complications of PAI could provide useful insights.Even under optimal glucocorticoid replacement, patients affected by PAI show decreased quality of life  and incrRecent studies have shown immune alterations in patients with PAI and SAI , 133, whThe role of ACTH in maintaining adrenal homeostasis and participating in the HPA axis is self-evident. However, after an initial number of studies on its potential as a therapeutic strategy in many diseases and conditions, researchers seem to have abandoned the “corticotropin path” and have focused more on its downstream hormone pathways (glucocorticoids and androgens). Owing to the advances in knowledge and methodologies, it is time to rediscuss the role of ACTH in affecting general outcomes in adrenal diseases and the possible use of its noncanonical effects to address unmet needs.VH: substantial contributions to conception of the manuscript, analysis and interpretation of data, drafting the article, revising it critically, and final approval of the version to be submitted. IB, MM, ES, and VS: substantial contributions to conception of the manuscript, analysis and interpretation of data and drafting the article. ES: substantial contributions to revising the manuscript critically for important intellectual content, and final approval of the version to be submitted. AI: substantial contributions to conception and design of the manuscript, drafting the article and revising it critically for important intellectual content, and final approval of the version to be submitted. All authors contributed to the article and approved the submitted version.The project was partially funded by the CHRONOIMAGE project (PRIN 2017HRTZYA) by MIUR.AI has served as a consultant in the advisory boards for Novartis, Takeda, Recordati, and Sandoz and has received unconditional research grants from Shire, IPSEN, and Pfizer.The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


The use of waste products in the production of asphalt binders and asphalt mixtures has become widespread due to economic and environmental benefits. In particular, the use of recycled waste plastic in asphalt binders and mixtures is gaining more attention. This review presents analyses and comparisons of various forms of waste plastic used in asphalt modification, and approaches to incorporating waste plastic into asphalt mixtures, both for single and composite modifications. It focuses on the properties of waste plastics, asphalt binders, and asphalt mixtures. Overall, the incorporation of plastic waste into asphalt mixtures can significantly improve high-temperature performance and has potential economic and environmental benefits. The performance of modified asphalt is highly dependent on multiple factors, such as waste sources, waste plastic dosages, blending conditions, and the pretreatment methods for waste plastic. There are different ways to apply waste plastics to blend into a mixture. In addition, this paper discusses the current challenges for waste plastic-modified asphalt, including the stability, low-temperature performance, modification mechanism, and laboratory problems of the blends. The use of chemical methods, such as additives and functionalization, is considered an effective way to achieve better interactions between waste plastics and the binder, as well as achieving a higher sufficiency utilization rate of waste plastics. Although both methods provide alternative options to produce waste plastic-modified asphalt with stability and high performance, the optimal proportion of materials used in the blends and the microcosmic mechanism of composite modified asphalt are not clear, and should be explored further. Plastics have been widely used in diverse fields for their substantial benefits in terms of cost-effectiveness, light weight, durability, and ease of processing relative to many other materials ,2. The iThe widespread use of plastics brings great convenience to everyday life and promotes economic and social development. However, approximately 50% of plastic materials are single-use materials, such as packaging, agricultural films, and disposable consumer items. Between 20 and 25% of plastics are used for long-term infrastructures such as pipes, cable coatings, and structural materials . At the Additionally, the improper handling of plastic waste leads to a high content of plastics in MSW incineration-bottom ash (MSWI-BA). The disposal of MSWI-BA results in an increase in contaminants that pollute water, soil, and oceans ,10,11. MThe recycling and utilization of plastic waste have been considered a golden management strategy for reducing environmental impact and natural resource depletion ,15. WithChina’s road network has developed an ascending trend since 2008, and as of 2020, consists of over 5.20 million kilometers of roads due to rapid urbanization and economic growth . AsphaltIn an attempt to improve the durability and reliability of asphalt pavements to meet the climatic, traffic, and other requirements, the use of modified asphalt instead of raw asphalt has long been recommended as an effective approach . It has Various studies and research projects have been conducted to find appropriate applications of using waste plastics in asphalt production, discussing the properties of waste plastic-modified asphalt, modified mechanisms, and environmental concerns ,24. In gThis paper is a literature review that critically presents the recent progress, developments, and challenges in the application of waste plastic-modified asphalt binder and mixture technologies. This paper is not the first review of this topic, but it renews the latest developments in the field. It focuses on the approaches for waste plastic-modified asphalt and mixture production, the influences of the main factors including the types and dosages of waste plastic, blending conditions and pretreatment methods on the properties of modified asphalt binder, and the discussion of the performance of waste plastic-modified asphalt mixtures, life cycle assessment (LCA) and practical engineering applications. In addition, compared with other reviews, this paper discusses the current challenge for waste plastic-modified asphalt including the stability, low-temperature performance, the modification mechanism, and laboratory problems of the asphalt blends, as well as provides potential ways to improve the properties of waste plastic asphalt and mixtures.Plastics are synthetic materials derived primarily from refined crude oil petroleum products ,29. TablDifferent types of waste plastic have drastically different characteristics, which are mainly affected by chemical composition, chemical structure, and average molecular weight . For exa2) and fiber form (less than 2 mm). Furthermore, waste HDPE powder and electronic-plastic (e-waste) powder Waste LDPELDPE has a lower specific gravity, strength, and temperature resistance than HDPE because of its long, flexible, and linear polyethylene chain . Due to (2)Waste HDPEAs discussed above, the high crystallinity of HDPE makes it difficult to immerse in asphalt, which also affects the compatibility of modified asphalt. It is agreed that the waste HDPE-modified asphalt has higher stiffness and viscosity, and better moisture resistance . Costa e(3)Waste PPRecycled PP-modified asphalt has the common characteristics of thermoplastic polyester modified asphalt, especially the superiority of high-temperature performance. However, the addition of waste PP reduces the ductility of modified asphalt and decreases the fatigue cracking performance . Specifi(4)Waste PVCRecent studies have shown that the addition of waste PVC increases the viscosity and stiffness of base asphalt so that the modified asphalt has better rutting resistance. One possible reason is that the chloride and carbon bond dipole in PVC provides a greater stiffness . A study(5)Waste PETAccording to the Wellness Recovery Action Program (WRAP), PET is one of the most recycled plastic wastes . Because(6)Waste PSWaste PS-modified asphalt mixtures developed using the dry process are found to have higher rigidity, but this could be a problem in colder areas in terms of cracking resistance . Specifi(7)Waste EVAWaste EVA has good compatibility with asphalt, so it has been widely studied and applied. The results have shown that the large volume of the vinyl acetate group becomes a non-crystalline area or amorphous area, which plays a role similar to rubber when EVA is mixed with asphalt. The crystalline area of EVA has high stiffness, which acts as a reinforcing bar, and greatly improves the high-temperature stability, low-temperature cracking resistance, and viscosity of modified asphalt . It also(8)Waste ABSThe most common e-plastics used in the manufacture of electronic devices are ABS. Evidence from recent studies indicated that the use of e-plastic powders for asphalt modification helped improve the asphalt’s viscosity and blending and mixing temperatures, meanwhile decreasing rutting susceptibility compared to virgin asphalt . The low(9)Waste PUBazmara et al.  used theThe application of waste plastic as an independent modifier in asphalt is rare in current studies and engineering practices. This is because the key properties of asphalt cannot be improved by using only one type of waste plastic. In order to enhance and optimize the properties of waste plastic-modified asphalt binder to meet the needs of increased traffic demands, there has been growing interest in composite modification. Recently, more and more studies have investigated the properties of modified asphalt binders containing waste plastic and various materials . This inThe characteristics of waste plastics, such as type, chemical composition and structure, and molecular weight, affect the time required for blending, as plastics with higher molecular weight require more time to blend homogeneously with the asphalt binder. Additionally, waste plastics are produced in smaller sizes to help disperse and dissolve into the asphalt binder .PE is one of the most popular thermos-plastics, and it is one of the earliest waste plastics to be used as an asphalt modifier in the world. PE has the simplest polymer structure, with each carbon atom connected to two hydrogen atoms. PE is categorized based on density into HDPE, LDPE, and Linear LDPE (LLDPE) . EvidencIn recent years, various types of waste plastics have been used as an asphalt modifier. Hu et al.  reportedAsphalts are composed of two main phases: (1) an oily phase consisting of saturated hydrocarbons, aromatic cyclic products, and resins, and (2) a non-oily phase formed by asphaltenes and carbenes; however, the chemical composition and structure are different . ElementThe utilization of suitable waste plastics in asphalt modification shows an improvement in asphalt properties; however, there is an optimum point between the waste dosage and asphalt properties. Many studies available investigated the effects of modified asphalt containing waste plastics at various dosages on its properties and pavement performance. The dosage range of common polymer-modified asphalt is between 2.5 wt% and 3.5 wt%, with a higher dose range greater than 7 wt% being referred to as highly modified asphalt . MashaanThe results from recent studies indicated that the blending conditions  used for asphalt modification strongly affect the asphalt properties ,112,119.The optimum blending conditions used for various types of waste plastic-modified asphalt are summarized in It is necessary to carefully consider the appropriate pretreatment method for waste plastic before it is added into the asphalt, as it affects the compatibility between the asphalt and modifier. Generally, pretreatment methods can be divided into two main methods: the physical method and the chemical method. It seems that most researchers (approximately 85%) prefer using the physical method to pretreat waste plastics, according to all of the related research papers referenced in this review.Waste plastics can be processed into smaller particles through physical methods such as grinding, shredding, pulverization, and extrusion.The use of the chemical method for the preparation of waste plastic is commonly carried out through grafting or irradiation to provide better compatibility and properties with the modifier, so that the performance of modified asphalt is improved. Li et al.  successfIn recent studies, a novel method named irradiation was used for pretreating waste plastic. Ahmedzade et al.  found thMost studies have demonstrated that the addition of waste plastics significantly increases the stiffness and rutting resistance of base asphalt and mixture, and thus, has the potential to extend the service lives of asphalt pavements ,99,129. Based on the results of laboratory tests on asphalt binders, it can be expected that highly modified asphalt mixtures will have better functional properties, durability, and anti-rutting resistance . LaboratCurrently, the main types of waste plastic-modified asphalt mixture are stone matrix asphalt (SMA) and asphalt concrete (AC). Plastic gives an increase in stability, split tensile strength, and compressive strength compared to the conventional SMA mixture . But theSome scholars have tried to use waste plastics in the reclaimed asphalt pavement (RAP) mixture, which also gives us an alternative way to alleviate the environmental problems caused by plastics. The results have shown that the addition of waste plastic materials into the RAP mixture potentially improves the durability of the pavement . By cont2 equivalent emissions can be decreased by 10.2% when 8% of virgin PP is replaced with the same amount of waste PP, and the emission decreases by 15.6% when waste PP is used to replace SBS. More evidence is needed to show that the implementation of these waste plastics into the pavement is eco-friendly [The environmental benefit is obvious, even if the total amount of waste plastic is a small part of the total asphalt mixture. Studies have shown that the COfriendly .2, and energy compared to conventional asphalt mixtures using all of the virgin components. Another study showed that the energy consumption can be reduced by 2.23% when an asphalt mixture with waste plastic instead of a conventional asphalt mixture is used as a surface course material [The LCA method is typically applied to quantify the environmental impacts of using waste plastics in asphalt and asphalt mixtures throughout their entire life cycle—from raw material extraction, to transport, manufacturing, and use. Poulikakos et al.  assessedmaterial . Santos material  also obtmaterial . The cramaterial .Multi-attribute analysis methods, including environmental factors, costs, and engineering properties, have been conducted to investigate the overall problem of plastic recycling on the road for mixture sustainable factors . The resSome researchers have taken a step in evaluating the performance of waste plastic-modified asphalt mixtures by assessing actual field performance, not only at the laboratory level.(1)IndiaWaste plastics have been widely used in road construction in India. Since 2002, more than 2500 km of asphalt concrete pavements have been modified with polymer waste using the dry method. In the following years, six sites were selected to investigate the status of waste plastic asphalt pavement. The results showed that these roads worked well, without potholes, raveling, and rutting .The Indian Highway Congress published guidance for the use of waste plastics in the bituminous mixture in 2013, while the National Rural Highway Development Agency provided guidelines on the use of waste plastics in rural road construction .(2)UKMacRebur’s recycled waste plastic was incorporated into the asphalt instead of traditional bitumen and used by Durham County Council in the UK for resurfacing a section of A689 near Sedgefield, and for resurfacing runways and taxiways at Carlisle Airport in the UK.The Department for Transport provided £1.6 million to extend Cumbria’s existing road that is built from recycled plastic mixed with asphalt. The trial will also produce a guidance document on the use of plastic asphalt.(3)USAUC San Diego built the first asphalt road made with recycled plastic binder as opposed to a petroleum-based bitumen binder in the USA.(4)AfricaThe local government is building the first plastic road in the city of Kouga municipality, South Africa. It is reported that a 1-kilometer ‘plastic road’ could consume nearly 700,000 plastic bottles or 1.8 million plastic bags.(5)The NetherlandsIn June 2021, the PlasticRoad Company built the first parking spaces and residential street using waste plastic in the municipality of Almere; in the same year, waste plastic was used to construct a car-sharing location in the province of Overijssel and the municipality of Hardenberg, and to build a bike path at Delft University of Technology.(6)MexicoThe modular design of Mexico City’s PlasticRoad offers temporary water storage and drainage features. The use of waste plastics on actual roads has just started, and most plastic roads are piloted in bicycle lanes, runways, and rural roads. Only the waste plastic roads in Africa have follow-up reports, and the long-term outcomes of many pilot roads are not yet clear.There is no doubt that the utilization of waste plastics with asphalt significantly improves the asphalt’s high-temperature performance ,31,129. Studies reported by Yan et al.  and KalaHowever, the evaluation index of waste plastic-modified asphalt on low-temperature performance is controversial. The assessment of asphalt’s low-temperature performance in China is mostly based on the Bending Beam Rheometer test and the ductility test. Yang  suggestePoor storage stability is one of the main drawbacks of polymer-modified asphalt . It is pComposite modified asphalt is a multiphase system. The composite modifier is an intimate blend that comprises at least two incompatible polymers forming a two- or multi-phase blend including waste plastic and other polymers. Phase separation could occur caused by the asymmetric molecular dynamics among the components in the composite modifier . The modThe modification mechanism of polymer on asphalt is complex. The interaction principle of the waste polymer has not been comprehensively and systematically investigated. Most scholars have successfully explained the modification mechanism of waste polymers and base asphalt by the “swelling mechanism”. As can be seen from Fang et al.  found thMicroscopic technology and infrared spectroscopy are effective tools for helping scholars to investigate the modification mechanism. The modifier and binder in the system may go through physical blending or chemical reaction, and the process is difficult to define. Fourier transform infrared spectroscopy (FTIR) can be used to qualitatively and quantitatively analyze the composition of functional groups of materials according to the principle that specific functional groups and chemical bonds selectively absorb infrared light at specific wavelengths, to clarify the modification mechanism of asphalt .−1 and 2856 cm−1 because the modified asphalt contains a large number of methyl and methylene groups, which coincide with the absorption peaks of the asphalt before modification. However, other functional groups do not change before and after modification, indicating that the waste LDPE modification of asphalt is also a physical process [The use of FTIR can quantify the absorption bands. Some researchers found that there was no change in the main functional groups of waste PVC asphalt binder, indicating the modification is a physical effect . Other r process .Microtechnologies, including scanning electron microscopy (SEM) ,155, atoThe dispersion of modifiers and the structure form can be seen clearly in the microscopic image. This shows the impacts of modifiers on asphalt and reveals the modification mechanism. This paper summarizes the fluorescence microscopic images of different types of plastics, as shown in The uneven dispersion and aggregation of modifiers may be encountered in the laboratory during the modification process of waste plastics. Since asphalt binder is colloidal material, the agglomeration phenomenon naturally appears . The disThe aggregation of modifiers can be improved by improving the mixing conditions to a certain extent. As described in Waste plastic binders and mixtures are gaining increasing attention due to their engineering performance and economic and eco-friendly benefits. This paper presented a review of the waste plastics most commonly used in asphalt binders and mixtures, analyzed and compared various approaches for waste plastics-modified asphalt and mixture production, and discussed the influence of the main factors on the properties of modified asphalt and mixtures. The paper discussed the current challenges for waste plastic-modified asphalt, such as the stability, low-temperature performance, the modification mechanism, and laboratory problems. Based on this review, the following points can be drawn:(1) The use of waste plastic as an asphalt modifier expands the application field of waste plastic and avoids the waste of resources. It is also an effective way to solve the waste plastic disposal problem and reduce environmental pollution. However, more attention should be paid to PS and PVC, as these plastics produce harmful emissions when heated at high temperatures.(2) The source of waste plastics is one of the main factors that affect the performance of the modified asphalt due to the differences in chemical composition and structure, resulting in different basic characteristics. High melting point plastics, such as PVC, PS, and PVC, are more suitable for the dry processes; LDPE, HDPE, PP, and EVA, with low melting points, are more appropriate for the wet processes.(3) Waste plastic can be made into various forms and sizes depending on the specific purpose when used for asphalt modification. Waste plastic with a smaller size and larger surface area, combined with composite modification, is recommended to achieve better high- and low-temperature performance and storage stability.(4) A physical or a chemical modification can be accurately distinguished upon comparing the FTIR spectra before and after the asphalt modification. The microstructure of the modified asphalt, modification process, and mechanism can be further characterized using microcosmic technologies such as SEM, AFM, and CLSM. Previous studies have provided evidence that asphalt modified with waste plastic independently is a physical modification.(5) The use of the LCA method can effectively quantify the environmental impacts of using waste plastics for asphalt and asphalt mixture modifications. Waste plastic-modified asphalt mixtures indeed reduce energy consumption and emissions, and the implementation of these waste plastics into the pavement is eco-friendly. The use of waste plastics in actual roads has just started, therefore the long-term outcomes require further assessment.(6) There is no doubt that the high-temperature performance of waste plastic-modified asphalt is quite effective. However, there are still limitations for waste plastic-modified asphalt applications due to the separation between the waste plastic modifier and the asphalt, and the poor low-temperature performance of waste plastic-modified asphalt. Pretreatment methods  and composite modification  can improve the disadvantages of waste plastic-modified asphalt. However, due to the cost and application limitations, waste plastic asphalt modification requires suitable pretreatment and modification methods.As discussed above, waste plastic-modified asphalt is an important approach currently available to reduce environmental impact and natural resource depletion, and it deserves more attention to improve the interaction between the modifier and the asphalt to improve the asphalt properties and pavement performance.(1) Most of the studies presented in this review focus on assessing the properties of waste plastic-modified asphalt, but the microcosmic mechanism of asphalt modification has not received enough attention. Several studies report results that are characterized by micro-experiments, but the microcosmic mechanism of waste plastic modification is rarely involved. The microcosmic mechanism of waste plastic-modified asphalt is still not well understood, and more attention should be paid to address this knowledge gap.(2) There is a need to better understand and control the effects of using different types of waste plastic and other polymers as modifiers on the properties of the asphalt, and find an optimum proportion for the modifier. This will promote the application of recycled waste plastics in modified asphalt.


The mission of the human stress system is the maintenance of homeostasis in the presence of real or perceived, acute or chronic stressors. The hypothalamic–pituitary–adrenal (HPA) axis and the autonomic nervous system (ANS) are the stress system-related neuroendocrine pathways. There is abundant evidence that children and adolescents with autism spectrum disorder (ASD) may exhibit atypical function within the HPA axis and the ANS both at the resting state and during the presence of social and/or non-social stressors. The aim of this review is to provide an up-to-date summary of the findings regarding stress system alterations in children and adolescents with ASD. We focus on the variations of stress hormones circadian rhythms, specifically cortisol and alpha-amylase , and on the alterations of stress system responsivity to different stressors. Also, we present imaging and immunological findings that have been associated with stress system dysregulation in children and adolescents with ASD. Finally, we review the pivotal role of HPA axis-ANS coordination, the developmental trajectory of the stress system in ASD, and the possible role of early life stress in the dysregulation of the stress system demonstrated in children and adolescents with ASD. This synthesis will hopefully provide researchers with a foundation for an integrated approach to future research into stress system variations in children and adolescents with ASD. Autism spectrum disorder (ASD) is a heterogeneous group of neurodevelopmental disorders, which emerge early in childhood and are characterized by deficits in social interaction, verbal and non-verbal communication, and by restricted, repetitive patterns of behavior, interests, or activities . For 201In addition, children and adolescents with neurodevelopmental disorders may exhibit alterations in the diurnal rhythm and/or atypical responses of stress hormones, such as cortisol, to environmental stressors . It has The aim of this review is to provide an up-to-date summary of the findings regarding stress system alterations in children and adolescents with ASD. We focus on the available evidence regarding both variations in the circadian rhythms of stress hormones and alterations in the responsiveness of the stress system to stressors. We also attempt to cast light on the most acknowledged stress system-related neuroendocrine pathways  and their role in the pathophysiology of ASD. We also review imaging and immunological findings associated with stress system dysregulation in children and adolescents with ASD. Finally, we discuss the pivotal role of HPA axis and ANS coordination during stress system activation, the developmental trajectory of the stress system in ASD, and the possible role of ELS in the dysregulation of the stress system demonstrated in children and adolescents with ASD.via a plethora of mediators, including neuropeptides, neurotransmitters, and steroid hormones. The central effectors of the stress system comprise: (i) the neuropeptide CRH secreted by CRH neurons. The highest concentration of CRH neurons is present in the hypothalamic paraventricular nuclei (PVN). CRH is also secreted by neurons present in several brain regions . Additionally, CRH has been found in chromaffin cells of the adrenal medulla and in the sympathetic ganglia, as well as in peripheral organs and tissues, including the skin, the immune system, and the gastrointestinal tract  thal tract .via sympathetic splanchnic innervation of the adrenal gland , day cortisol decline (slope), or intra- and inter-individual cortisol level variability, are quite diverse in children and adolescents with ASD. For example, regarding CAR , a study that assessed salivary cortisol levels in adolescent males (aged 11–16 years) with Asperger syndrome (AS) reported a blunted CAR in the clinical sample compared to typically developing (TD) children . Also, aAs far as it regards the cortisol diurnal decline, no significant differences have been found between adolescent males with ASD and TD controls . NeverthThe most consistent finding across several studies regarding HPA axis regulation in children and adolescents with ASD is the higher between-subject and within-subject basal cortisol variability compared to controls . PreciseStudies that examine the responsiveness of the HPA axis by measuring cortisol in ASD children and adolescents suggested hyper- or hypo-responsivity depending on the nature of the stressor. For example, two studies reported a slower cortisol response to ACTH stimulation among ASD children indicated by lower plasma cortisol levels 60 and 90 min post-infusion compared to controls, whereas no differences were found between the groups after 120 min . ContrarConcerning non-social environmental stressors, i.e., stressors that do not explicitly manipulate the social environment, a lower rise of cortisol was found in children with pervasive developmental disorder – not otherwise specified (PDD-NOS) than in controls after riding a stationary bike for 10 min; however, a subsequent study found no differences in HPA axis responsiveness after the same physical activity , 2003. MStudies examining the HPA axis responsivity to psychosocial stressors in children and adolescents with ASD have produced conflicting findings. The majority of studies using public speaking tasks as stressors, such as the Trier Social Stress Test for Children TSST-C; , demonstn = 138; median age = 11.25 years) compared to TD children  demonstrated a blunted cortisol response and a faster return to basal cortisol levels in youth with ASD  , respiratory sinus arrhythmia (RSA) , and short-term heart rate variability (HRV) , have shown divergent findings regarding resting state autonomic functioning and autonomic responsiveness to several stress-inducing tasks in children and adolescents with ASD.A study comprising children with high-functioning ASD (8–12 years old) showed no differences in EDA or vagal tone at resting state, during the TSST-C, or post-TSST-C in comparison to the TD group . In contA study of the ANS response to a cognitive task  to a social evaluative threat the TSST . Also, ithe TSST . Similarthe TSST . Furtherthe TSST . The autthe TSST . Neverththe TSST .Salivary alpha-amylase (sAA), a putative surrogate of norepinephrine, has been extensively used as a non-invasive indirect index of SNS activity . Alpha-avia descending limbic projections from regions such as the medial prefrontal cortex (PFC) and the amygdala  . The CANamygdala . Thus, damygdala . Accordiamygdala . Most imamygdala . The autamygdala .Of note, the majority of data comprising ANS biomarkers in ASD children and adolescents generally converge on the presence of ANS hyper-arousal related to sympathetic overactivity, parasympathetic underactivity, or atypical interaction of both systems in ASD . InteresLimbic circuits connecting the hippocampus, the amygdala, and the PFC play a pivotal role in the induction of neuroendocrine and behavioral stress responses . The amyMoreover, it is well established that stress causes structural and functional brain changes, mainly during critical periods of brain development . Of noteThere is a bidirectional neuroimmunoendocrine interaction between the central and peripheral stress system components and the immune axis . For exavice versa, cortisol exerts a mild inhibitory effect on the peripheral production of IL-6  of subjects . For exavia alterations of fetal and maternal levels of cortisol and testosterone  in ASD children and adolescents. Accumulating evidence suggests that children and adolescents with ASD may demonstrate dysfunction of the HPA axis and/or the ANS at baseline, in resting state, and during social and non-social stress challenges.In summary, baseline and/or resting state cortisol dysregulation is not consistently found in children and adolescents with ASD. The majority of studies have shown comparable cortisol awaking response (CAR) between the ASD and TD groups . Also, lThe majority of studies regarding resting state autonomic functioning converge on lower resting PNS activity accompanied by higher SNS activity in children and adolescents with ASD . In factDiscrepancies in the findings across studies may be due to several factors, such as differences in subject ages or developmental level, the severity of impairment, medication use, presence of comorbidities, the size of the sample groups, investigative methods employed, and the type of stressor used . Thus, fImportantly, the HPA axis and the ANS are interrelated components of an internal neurohormonal regulatory system . The degMoreover, several brain regions, such as the hippocampus, the amygdala, and the PFC play a pivotal role in the induction of neuroendocrine and behavioral stress responses . These bFurthermore, the altered stress system neuroendocrine interface demonstrated in children and adolescents with ASD might be closely correlated to immunological alterations also seen in ASD . Also, iFinally, prenatal stress and ELS are risk factors for ASD . EpigeneTo date, the presence of inconsistencies in the observations regarding the stress system dysregulation in children and adolescents with ASD is the main caveat to any generalizations and biomarkers detection. Also, the fact that the majority of data points toward inconclusive results raises a question about the supposed specific role of the stress system in the pathophysiology and the clinical presence of ASD. While there is evidence of an aberrant cortisol circadian rhythm and alterations in stress system responsivity in children and adolescents with ASD, the extent and the relations of these changes and their underlying mechanisms remain unclear and warrant further study. Thus, the first step needed, to clarify the role of at least specific aspects of stress system alterations in ASD, is the in-depth research toward the understanding of possible mechanisms linking stress system alterations with this neurodevelopmental disorder. The elimination, where is possible, and the thorough study of any confounding factors, such as the severity of symptoms, comorbidities, developmental level, and gender are also necessary steps. Moreover, large, prospective, and methodologically focused studies in well-characterized clinical samples are needed, to clarify if the stress system is involved in ASD in a specific manner and/or if etiologic relations between stress system dysregulation and neurodevelopmental deficits exist. Therefore, the question of whether the associations between stress system alterations and ASD symptoms are bidirectional remains. The current review is an attempt to foster a multimodal approach to the stress system dysregulation found in ASD children and adolescents. An integrated approach should comprise the assessment of possible correlations between neuroendocrine alterations and imaging findings, immunological alterations, epigenetic marks, and prenatal and early life environmental risk factors that play a pivotal role in the stress system programming. Also, it is necessary to comprehensively investigate the functional importance of the circadian clock in neurodevelopment and its dysregulation in neurodevelopmental disorders . FinallyPP: conceptualization and supervision. GM: writing and original draft preparation. AA, GC, and PP: writing, reviewing, and editing. All authors have read and agreed to the published version of the manuscript.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


Scars are a common disfiguring sequela of various events such as acne, hidradenitis suppurativa, surgery, trauma, and burns, which can lead to serious psychosocial problems with a negative effect on the quality of life. Many conventional approaches have been proposed for the treatment of scars, including surgical techniques, dermabrasion, chemical peels, topical silicone gel, 5-fluorouracile and dermal fillers injection or autologous fat transfer for atrophic scars, and corticosteroids injection for hypertrophic and keloid scars; however, they have sporadic effects. Ablative lasers, such as carbon dioxide laser or Erbium Yag laser, are associated with many collateral effects limiting their application. Non-ablative laser treatments have been shown to be safer and to have fewer side effects, but they have a reduction of clinical efficacy compared to ablative lasers and a minimal improvement of scars. The demand for minimal invasive and safe technology for the treatment of a scars has stimulated the search for more effective novel therapy with fewer collateral effects. Plasma radiofrequency ablation is a new technique consisting of the generation of plasma energy through the production of ionized energy, which thermally heats tissue in a uniform and controlled manner, through a plasma radiofrequency device, inducing a sublimation of the tissue. The aim of this study is to evaluate the effectiveness of P-RF ablation in the treatment of scars performed with D.A.S. Medical device , which is a tool working with the long-wave plasma radiofrequency principle. Scars are a common disfiguring sequela of various events such as acne, hidradenitis suppurativa, surgery, trauma, and burns, which can lead to serious psychosocial problems with a negative effect on the quality of life .Skin tissue repair results in a broad spectrum of scar types, ranging from “normal” fine line scars to abnormal scars, including stretched, atrophic, hypertrophic, keloid scars, and scar contractures .Abnormal healing processes can complicate the normal wound healing, resulting in the development of proliferative scars, such as hypertrophic scars and keloids, resulting from excessive deposition of collagen at sites of prior dermal injury or of wound repair due to an imbalance between collagen biosynthesis and matrix degradation . HypertrAtrophic scars appear when dermal collagen and connective tissue production inadequately compensate for the tissue loss. They are depressed below the surrounding skin; small and round scars commonly arise after acne, hidradenitis suppurativa, or chickenpox.2 fractional laser, have been shown to have some beneficial effects on atrophic scars with short healing times, short downtime, and duration of erythema, yet post-treatment collateral effects can also occur, especially for Fitzpatrick skin type III and IV [Many conventional approaches have been proposed for the treatment of normal and abnormal scars, including surgical techniques, dermabrasion, chemical peels, topical silicone gel, 5-fluorouracil and dermal fillers injection or autologous fat transfer for atrophic scars, and corticosteroids injection for hypertrophic and keloid scars; however, they have sporadic effects ,3. For uPlasma radiofrequency ablation (P-RF) technique, recently used for the treatment of xanthelasma palpebrarum , full faThe demand for minimally invasive and safe technology for the treatment of scars has stimulated the search for more effective novel therapy with fewer collateral effects. Plasma radiofrequency (PRF) ablation is a new technique consisting of the generation of plasma energy through the production of ionized energy that thermally heats tissue in a uniform and controlled manner, through a plasma radiofrequency device, inducing a sublimation of the tissue . In contThe aim of this study is to evaluate the effectiveness of P-RF ablation in the treatment of scars performed with D.A.S. Medical device , a tool working with long-wave plasma radiofrequency principle.Following the receipt of the ethics waiver, 10 patients  affected by unsightly scars  were enrolled for longwave P-RF (LWP-RF) ablation treatments. Patients with scars younger than 2 years, or with keloids and burn scar contractures, were excluded from the study entry.Prior to the treatments, all patients signed an informed consent form. No contraindications to treatment, such as Fitzpatrick skin types V–VI, presence of tanning, concomitant infection, diabetes, pregnancy, use of oral isotretinoin within the previous 6 months, presence of collagen vascular disorders or other autoimmune diseases, ablative skin procedures carried out within the previous 3 months, and malignancy, were present.The scars to be treated  were anesthetized with topical anesthetic cream  without occlusion for 1 h before starting every treatment. The scars were disinfected with the antiseptic solution following the removal of the anesthetic cream with sterile gauze.In patients affected by post-acne atrophic scars and hidradenitis suppurativa atrophic/hypertrophic scars, LWP-RF ablation was performed in four sessions . Atrophic scars were treated at 0.6-watt energy and 3 Hz frequency with detached spots of sublimation performed on the edges around the scars, leaving columns of the intact epidermis and sparing the central atrophic part to break down the edges and to stimulate the rise of the central skin depression . The hypertrophic parts of hidradenitis scars were treated with superimposed passes at 0.6-watt energy and 2 Hz frequency to break down the thick skin .Post-traumatic hypertrophic scars were fully ablated in three sessions with two superimposed passes at 0.8-watt energy and 2 Hz frequency with no columns of sparing tissue, to break down the thickening . Once the scar was smoothened, the residual stretched appearance was ablated in further two sessions with only one pass at 0.6-watt energy and 3 Hz frequency with detached spots of sublimation to achieve the shrinkage .In all patients, the sessions of treatment were carried out at 40-day intervals, and the final endpoint for completion of the single session was moderate burnishing. After the LWP-RF procedure, they applied an antibiotic ointment for 10 days, avoiding sun exposure during the sessions and for 6 months after the last session.Treatment sessions and post-treatment period were well tolerated by all patients, which referred to only negligible concerns during the treatments. At the end of the sessions, only moderate burnishing was present; reepithelialization occurred within 7–10 days. All patients were followed up at 3 and 5 months from the last treatment, and the outcome was already visible at 3 months from the last treatment. No side effects, such as infections or dyschromia, occurred in any patient.A significant aesthetical improvement of the scars was observed after four LWP-RF sessions of treatment for all patients, with great improvement of the skin texture, reduction of the visibility of the treated scars, and high patient satisfaction B. Visual2 laser in the 1990s provided an important new tool for the treatment of scars that depicted very high efficacy [Over the past 35 years, the treatment of scars has undergone significant changes influenced by the development of new devices and technological evolution. The use of fractional lasers was an important step in scar therapy, and the advent of the high-energy pulsed COefficacy ,13. Howeefficacy . Fractioefficacy . The abiefficacy . NonablaPicosecond lasers have been used successfully for scars, especially for treating darker skin types and avoiding post-inflammatory hyperpigmentation . AnotherThe need to overcome the limits and difficulties posed by lasers has led to seeking alternative methods and tools that could make use of mechanisms other than laser technology.Plasma is “the fourth state of the matter” derived from the ionization of neutral gases present in the air ,7,8,9,10One of the main features of action offered by this technique compared to fractionated lasers that act homogeneously on the entire treated area is to customize the treatment millimeter by millimeter by acting focally on reducing the thickening of the hypertrophic area of the scar and the edges of the peripheral area of the atrophic scar. Moreover, it also involves stimulating the depressed atrophic area of the scar, similar to fractional laser action, stimulating its ascent up to the level of the skin plane. Added to this is the lack of side effects related to the absence of a light source, the ability of the plasma effect to moderate the heat transfer, and consequently, the reduction in the inflammatory effect, inducing, however, an advantageous stimulation of the dermis.The advantages of this technique include the lack of absolute contraindications, minimal intraoperative pain, quick treatment, rapid formation of the postoperative protection layer, fast healing of wound surface, immediate return to normal activity, and optimal results in the treatment of hypertrophic and atrophic scars.Finally, the low cost of the equipment compared to laser devices results in an added value to the advantage of both the operator and the patient, who access an effective treatment at significantly reduced costs compared to laser treatment.The limitations of the technique mainly concern the choice of the type of scar, as satisfactory results were not seen on keloids, so much so as to exclude patients with keloids from the study. The small number of patients recruited for P-RF-ablation treatments could represent a limitation of this study, therefore ensuring meaningful results; further clinical studies are needed on a larger number of patients to better determine the effects of this relatively new technique for the treatment of scars, alone or in combination with other kinds of treatments.In conclusion, the trend towards combined therapy in the treatment of scars has stimulated planning for the near future to evaluate the results of the combination of P-RF ablation with non-ablative lasers in order to settle the result and further improve the general appearance of the treated area without incurring any side effects.


Liver disease and gut dysbiosis are strictly associated, and the pathophysiology of this bidirectional relationship has recently been the subject of several investigations. Growing evidence highlights the link between gut microbiota composition, impairment of the gut-liver axis, and the development or progression of liver disease. Therefore, the modulation of gut microbiota to maintain homeostasis of the gut-liver axis could represent a potential instrument to halt liver damage, modify the course of liver disease, and improve clinical outcomes. Among all the methods available to achieve this purpose, fecal microbiota transplantation (FMT) is one of the most promising, being able to directly reshape the recipient’s gut microbial communities. In this review, we report the main characteristics of gut dysbiosis and its pathogenetic consequences in cirrhotic patients, discussing the emerging data on the application of FMT for liver disease in different clinical settings. Bacteroidetes, Lachnospiraceae, Ruminococcaceae, and Clostridium incertae sedis XIV are reduced while Proteobacteria, Fusobacteria, Clostridium cluster XI, Enterobacteriaceae, Enterococcaceae, Lactobacillaceae, Alcaligenaceae and Streptococcaceae are overabundant in cirrhotic patients . AlThe same group of Authors reported on the safety and tolerability of FMT with oral capsules in patients with recurrent HE in a randomized, single-blind, placebo-controlled trial  22]. Us. Us22]. With the limitation of the small sample size of these two studies, a lower gastrointestinal route preceded by administration of broad-spectrum antibiotics seems to favor FMT efficacy, being more effective to prevent HE recurrence. Considering the absence of significant SAEs, and the limited therapeutic options for patients with recurrent HE, further studies with larger sample sizes should be encouraged to clarify the best procedure to maximize the efficacy of FMT in cirrhotic patients with HE.The gut-liver axis could influence the host immune response to HBV, the susceptibility to hepatocyte damage, and the progression of liver disease to a more advanced stage of fibrosis.Alistipes and Bacteroides compared to healthy subjects. This alteration of the gut microbiota results in the reduced production of SCFA and antibacterial peptides, consequently compromising the intestinal barrier . Tw. Tw24]. Two hypotheses can explain how HCV infection can influence the gut-liver axis ,37. On oLactobacillus and Streptococcus . FM. FM25]. A retrospective study compared the outcomes of patients with severe alcoholic hepatitis treated with nutritional therapy (17), corticosteroids (8), pentoxifylline (10), or FMT (16)  26]. Pa. Pa26]. Based on these data, FMT could be a promising strategy to treat severe alcoholic hepatitis, however caution is required due to the small simple size of the available studiesand the lack of randomized trials.Bacteroides and Ruminococcus abundance correlate with the severity of liver inflammation and fibrosis . Ho. Ho29]. Alterations of the gut microbiota have also been recognized in patients with primary biliary cholangitis (PBC). However, whether these alterations are the cause or consequence of liver disease is still unknown. Gut microbiota contributes to maintaining immune homeostasis, so it has been supposed that dysbiosis can trigger hepatic immune dysregulation through different mechanisms, such as cross-reactivity and molecular mimicry . FurtherHaemophilus, Veillonella, Clostridium, Lactobacillus, Streptococcus, Pseudomonas, Klebsiella, and an unknown genus of Enterobacteriaceae; conversely, Sutterella, Oscillospira, and Faecalibacterium were decreased compared with controls. Interestingly, the evaluation of the gut microbiota profile after treatment with UDCA showed a reduction of Haemophilus spp., Streptococcus spp., and Pseudomonas spp., and an increase of bacterial genera that were enriched in controls  [Tang et al. analyzed the difference between the gut microbiota of 60 patients with treatment naive PBC compared to 80 healthy controls, and then evaluated the modifications after treatment with UDCA. Treatment naive PBC patients had a reduced gut microbiota alpha-diversity compared with healthy controls, a decreased abundance of Bacteroidetes, and an increase in Fusobacteria and Proteobacteria. Eight genera were significantly increased in PBC patients, including ra spp.) . Veillonella, which was strongly associated with the severity of liver inflammation. The authors also built a model able to distinguish patients with AIH from healthy controls based on the gut microbiota composition, in particular on the combination of Veillonella, Lactobacillus, Oscillospira, and Clostridiales.According to the actual knowledge, the immunological alterations associated with the pathogenesis of autoimmune hepatitis (AIH) are triggered by the interaction between genetic predisposition and environmental factors. In a recent study, Wei et al. analyzed the gut microbiota composition in steroid-naïve AIH compared to healthy controls . The resAt present, no study has evaluated the efficacy and safety of FMT in patients with PBC or AIH.The gut microbiota plays a crucial role in the modulation of the immune system and the inflammatory response, and is also involved in the regulation of several metabolic pathways. In the last few years, several studies have shown a link between chronic liver disease and the gut microbiota. Even though our understanding of the interaction between the gut and the liver is still incomplete, dysbiosis seems to be the mainstay of chronic liver disease at any stage. The dynamic changes of the gut microbiota play an important role in the initiation and progression of liver injury, and probably represent the first hit in specific settings, such as NAFLD.In light of this, the characterization of the gut microbiota and its modulation are promising diagnostic, prognostic, and therapeutic tools. Microbial signatures used in addition to clinical parameters can help in early diagnosis and in the avoidance of invasive diagnostic procedures. A shift in the gut microbiota composition during patients’ follow-up or during the course of hospitalization could help to identify patients at high risk of unfavorable clinical evolution. Nevertheless, targeted approaches in the modulation of the gut microbiota may be more effective than the use of broad-spectrum antibiotics or conventional probiotics. In this regard, FMT is the most powerful tool to reset the gut microbiota derangement consequent to chronic liver disease, and should be implemented in daily clinical practice to act synergistically with conventional medical therapy.At present, there are no standardized guidelines regarding the indications and the choice of the ideal FMT procedure to be used in clinical practice in patients with chronic liver disease. In the previously analyzed studies, FMT was administered with different schedules as regards dosing and frequency, delivery modalities, and formulation. Although endoscopic techniques are reasonably safe, they are costly, invasive, they have potential procedural risks, and their repeatability over time may be limited. Enemas and nasoduodenal tubes are less invasive and less expensive but have some limitations. Enemas can fail to deliver fecal material throughout the colon if retention of the instilled material is not adequate. Nasoduodenal tube placement could elicit nausea, regurgitation, vomiting, and aspiration. The administration of FMT through oral capsules appear the safest and less expensive technique to deliver bacteria to the intestine. However further studies are needed to identify the ideal method of FMT administration in patients with chronic liver disease.


Filamentous fungi are able to synthesise a remarkable range of secondary metabolites, which play various key roles in the interaction between fungi and the rest of the biosphere, determining their ecological fitness. Many of them can have a beneficial activity to be exploited, as well as negative impact on human and animal health, as in the case of mycotoxins contaminating large quantities of food, feed, and agricultural products worldwide and posing serious health and economic risks. The elucidation of the molecular aspects of mycotoxin biosynthesis has been greatly sped up over the past decade due to the advent of next-generation sequencing technologies, which greatly reduced the cost of genome sequencing and related omic analyses. Here, we briefly highlight the recent progress in the use and integration of omic approaches for the study of mycotoxins biosynthesis. Particular attention has been paid to genomics and transcriptomic approaches for the identification and characterisation of biosynthetic gene clusters of mycotoxins and the understanding of the regulatory pathways activated in response to physiological and environmental factors leading to their production. The latest innovations in genome-editing technology have also provided a more powerful tool for the complete explanation of regulatory and biosynthesis pathways. Finally, we address the crucial issue of the interpretation of the combined omics data on the biology of the mycotoxigenic fungi. They are rapidly expanding and require the development of resources for more efficient integration, as well as the completeness and the availability of intertwined data for the research community. One of the main aspects that fully describes the complexity of the life of filamentous fungi is the diversity of their metabolic pathways. This implies a variety of enzymatic activities that give fungi access to a vast array of substrates and, additionally, the ability to synthesise a remarkable range of secondary metabolites, also known as natural products. In general, these bioactive compounds can play various key roles in the interaction between fungi and the rest of the biosphere, determining their ecological fitness . Their pAmong the most important and dangerous mycotoxins, there are aflatoxins, ochratoxins, trichothecenes, fumonisins, zearalenone, and patulin; all of them are regulated for their presence in food and feed by national and European legislation. They are produced by a wide range of fungal species and are able to contaminate large quantities of food, feed, and agricultural products worldwide, posing serious health and economic risks, by themselves or through synergistic interactions with each other ,3. MycotFusarium and Alternaria, the omic analyses applied to both the fungus and the host plant could shed new light on ecological and molecular aspects of the symbiotic relationship and the consequent mycotoxin production.The elucidation of the molecular aspects of mycotoxin biosynthesis has been greatly accelerated over the past decade due to the advent of next-generation sequencing (NGS) technologies, which greatly reduced the cost of genome sequencing and related omic analyses. The massive number of genomic, transcriptomic, and proteomic data associated with metabolomic data provides both evidence of new unknown compounds and clarification on the mechanism of regulation of known fungal metabolites, and in particular, mycotoxins ,12. In fIn this context, this review briefly highlights recent progress in the use and integration of omic techniques with particular attention to genomics and transcriptomics, for the study of mycotoxins biosynthesis pathways and regulations. The genetic manipulation method, which now makes use of advanced genome-editing technologies, is also crucial for explaining the molecular mechanisms of biosynthesis by allowing the identification of key genes and their role in the pathways. Another important aspect considered here is the issue of the right management of omic data, which has become urgent as a result of the exponential increase of omic studies and repositories. In https://fungidb.org/fungidb, accessed 25 June 2021) and AspGD , the latter of which is specific to Aspergillus species. Worthy of note is the recent project “1000 Fungal Genomes” at the Joint Genome Institute (JGI) for the sequencing of multiple fungal genomes; MycoCosm is the related portal  at which integrated resources allow researchers to easily access and analyse a large number of fungal genomic data [Aspergillus species genomes (about 200) have been sequenced, compared to the few tens belonging to Fusarium and Penicillium genera. In some cases, the genomes of several strains belonging to the same species have been sequenced with the aim of highlighting and analysing differences due to distinct sources  and geographic origins, as expected in a pangenomic study. Availability of genomic sequences is of great help for the identification of secondary metabolism BGCs. Filamentous fungi are producers of a diverse array of secondary metabolites, which may have highly valuable bioactive effects and potential biotechnological interest. However, most of them may not be expressed under standard experimental conditions and metabolic phenotyping does not allow their discovery [pks and nrps genes enabled progress in the description of the OTA biosynthesis pathway in producing species [In recent years, the advanced development of NGS technologies has enabled the sequencing of a large number of filamentous fungus genomes, with an exponential increase in genomic data that will continue in the near future. Most of the fungal genome data are available on the NCBI database and on several sites dedicated to fungal research, for example, Fungi DB  on the regulation of the mycotoxin biosynthesis process in order to better estimate the mycotoxigenic risk associated with climate change factors. Most of these analyses regarded the biosynthesis of aflatoxin, whose molecular and regulatory mechanisms have so far been widely investigated, and stress factors have been taken into consideration acting alone or in combination [A. flavus, treatments with resveratrol [A. flavus lacking in the homeobox domain transcription factor hbx1, Cary et al. [hbx1 as a global regulator that controls several thousand genes and can influence the expression of an elevated number of transcription factors and developmental regulators, together with large numbers of secondary metabolite gene clusters including aflatoxin. Among the global regulators of secondary metabolism in fungi, by far the most studied was the heterotrimeric Velvet complex, consisting of LaeA, VeA (or Vel1), and VelB (or Vel2) proteins, which was found to regulate sexual development and secondary metabolism in several mycotoxigenic fungi [laeA gene was deleted or inactivated, and gene expression analyses of specific mycotoxin biosynthesis genes were performed. A comparative transcriptomic study between laeA deletion and overexpressing mutants in A. niger showed that these types of analysis on global regulators allow the identification of several differentiated gene clusters and transcription factors not yet characterised [F. verticillioides, in the presence of a histone deacetylase inhibitor, indicated a clear and differential role for chromatin remodelling in the regulation of FUM genes [rmtA encoding a methyltransferase in A. flavus was shown to regulate aflatoxin biosynthesis and fungal development, and in a subsequent RNA sequencing work, its influence on the whole transcriptome of A. flavus was demonstrated, identifying rmtA-dependent genes, including numerous transcription factors [Transcriptomics represents the link between genome and metabolome. Transcriptional profiling is important to understand the genes that are transcriptionally coregulated during secondary metabolites production to define both structural and regulatory genes involved. The production of metabolites/mycotoxins changes under different environmental conditions, and the impact of climate change factors can be estimated by taking into account the chemical, biochemical, physiological, and molecular aspects as a whole. In this regard, the transcriptional studies allow the estimation of the impact of climate change factors and the identification of the molecular pathways activated in response to diverse environmental cues, such as nutrient availability, light, pH, and temperature. Other conditions, concerning internal factors such as sexual cycle and developmental stage, or interaction with other microorganisms, plants, and animals, are known to influence greatly the production of mycotoxins ,7. The mbination ,33,34. Tbination ,36, suchveratrol , gallic veratrol , and ethveratrol  were fouveratrol ,41. In averatrol ,43. In ay et al.  describecterised . LaeA prcterised . EpigeneUM genes . More re factors .fum1 gene in fumonisin biosynthesis in F. proliferatum by deleting this gene through a novel CRISPR/Cas9-based genome-editing method that allows direct delivery of preassembled Cas9 ribonucleoproteins into fungal protoplasts. One of the most interesting aspects of using the CRISPR/Cas9-based technique is the possibility of simultaneous modification of multiple genes. Currently, different methods of multigene targeting with a single transformation are available for filamentous fungi [Deletion of biosynthetic cluster genes, coupled with metabolic analysis to detect the absence of the expected metabolite and/or the accumulation of intermediate molecules, has been the most successful strategy to clarify their function and to determine the biosynthesis pathway of the most important mycotoxins ,49,50. Sus fungi ,58,59,60https://img.jgi.doe.gov/abc-public, accessed 25 June 2021) [https://antismash-db.secondarymetabolites.org/, accessed 25 June 2021), and MIBiG  [https://bigfam.bioinformatics.nl, accessed 25 June 2021). Another important and challenging aspect of managing big data on BGCs is the comparison among data and datasets from different experimental approaches as well as different data processing platforms and workstations, which may provide different information. Essential structural details and early data processing of analysis results help in obtaining a correct interpretation of the complex information provided in primary datasets [https://pairedomicsdata.bioinformatics.nl/, accessed 25 June 2021). The growth of multi-omics experiments has promoted the development of metadata databases, such as BioProject and BioSample [The rapid expansion of data on the biology of the mycotoxigenic fungi poses the problem of their integration to better interpret and exploit them. The crossmatch of all the omic datasets in the “genomics–transcriptomics–proteomics–metabolomics” chain may result in an integrated approach that is essential to elucidate the complex system of mycotoxin production and understand the interaction between primary and secondary metabolism in fungi. In this respect, the research community is generating an increasing amount of omic data, which have been deposited in different dedicated repositories, and in the meantime, tools are rapidly being developed for mining these data . In recene 2021) , antiSMAne 2021)  have a cne 2021) ,67. In tne 2021)  have devdatasets . This undatasets . Interesdatasets , has beedatasets  have devioSample  and, morioSample , which pioSample  on the iOther new genotype technologies and approaches are under development to explore aspects of the mechanisms of mycotoxin production. Among these, the study of microbial communities as a whole (meta-omics) may offer a more comprehensive strategy to understand the function of mycotoxins, and how their production is regulated during the interaction among both fungus–fungus and fungus–bacteria microorganisms. In this regard, the meta-omic strategy has been reviewed in detail recently , highlig


The quantum dot is a kind of nanoparticle whose dimension is smaller than the size of a typical nanoparticle ranging from tens of nanometers to a few hundredths of nanometers. The quantum mechanical behavior associated with the quantum dot displays different optical and electronic properties, enabling the quantum dot to find potential applications in a multitude of areas such as solar cells, light-emitting diodes, lasers, and biomedical applications. The objective of this investigation is to explore its fundamentals, synthesis, and applications, especially in the healthcare domain. We have discussed the quantum dot synthesis techniques using chemical methods, namely, wet-chemical methods and vapor-phase methods and plasma processing methods, namely, an ion sputtering method and plasma-enhanced chemical vapor deposition method. We have thoroughly investigated the application of quantum dots in imaging, diagnostics, and gene therapy areas. A significant outcome of this review is to propose quantum dots as a new modality in the treatment of cancer and gene therapeutics in the healthcare domain and the potentials of artificial intelligence to improve their performance via the applications of neural networks. From solar panels to medical applications, quantum dots are receiving discernible attention in today's world due to their unparalleled and cutting-edge scope , 2. QuanNowadays, these quantum dots have been the subject of numerous exceptional reviews. One important attribute to note is that quantum dots are semiconductor nanocrystals. One of the most important characteristics of quantum dots is the conductive region of semiconductor heterostructure that comprises the precisely regulated quantity of excess electrons which are constrained to a small region by the application of external electromagnetic radiations. These parameters can be altered to achieve the desired configuration of the quantum dot to meet the requirements of different applications. The energy levels of quantum dots are mainly determined by two factors, first, the size of the quantum dots, and second, the intensity of external electromagnetic fields under which the corresponding quantum dots are exposed. Moreover, quantum dots can also be used in the field of quantum computation and artificial intelligence (AI). The quantum dots can be fabricated on the layer of semiconductor heterostructure to construct a three-dimensional matrix of quantum registers. The fact that quantum dots can easily be drafted and controlled according to application requirements makes it advantageous, particularly for quantum neural processing networks .The structure of these nanocrystals comprises a fluorescent semiconductor ‘core' which has excellent optical properties  due to coating with another semiconductor material which acts as passivation for “core” and is hence known as “shell”. The shell has a generally greater bandgap than the core shell that passivates the surface of the core and inhibits nonradiative recombination processes, which can act as a trap state of electrons in the conduction band, and as a consequence, it can lead to a reduction in the fluorescence efficiency, also referred to as photobleaching. Thus, the passivation of the core from the shell is important to improve its photostability and increase quantum yield (brightness) and also to reduce chemical attacks. As a result, the optical properties of quantum dots get less sensitive to changes in their surroundings. This characteristic of core-shell quantum dots is widely used in applications for biological imaging, chemical sensing, and optoelectronics .Fabrication of quantum dots can be led by various techniques according to the core requisites of the application. These methods of synthesis of quantum dots can be broadly categorized into two approaches, bottom-up approach and top-down approach . The botAnother well-known technique, etching, is important in nanoscale fabrication. Dry etching involves embedding a reactive gas species into an etching chamber and applying a radio frequency voltage to create a plasma that breaks down the gas particles into more volatile parts . These hVarious techniques are used to synthesize quantum dots in the bottom-up approach, and they can be narrowly divided into wet-chemical and vapor-phase approaches. Wet-chemical methods such as microemulsion, sol-gel, competitive reaction chemistry, hot-solution decomposition, and electrochemistry are all classified as (1) wet-chemical methods. Vapor-phase methods include self-assembly of nanostructures in material grown by molecular beam epitaxy (MBE), ion sputtering, liquid metal ion sources, and aggregation of gaseous monomers .Wet-chemical methods are generally used to prepare colloidal quantum dots. These methods are based on the conventionally performed precipitation methods with more precisely controlled parameters for single or compounded solutions. Invariably, both homogeneous nucleation  and controlled growth of quantum dots are involved in the precipitation methods. Quantum dots of the desired shape, composition, and dimension can be accomplished by altering, layer thickness, temperature, electrostatic potential, micelle or stabilizers forming, forerunner concentrations, concentrations of anionic and cationic agents, and solvent .However, there are some inherent drawbacks, such as relative instability, associated with the colloidal synthesis of quantum dots. When chemically synthesized quantum dots are coupled with devices, stabilization is mandatory. The stabilization of quantum dots usually involves the construction of a core-shell structure and passivation of quantum dot nanocrystals. Lately, surface chemistry methods of immersing quantum dots in polymer/glass matrices have aroused interest. By this modiﬁcation, the dangling bonds of quantum dots are blocked. In both quantum dots/polymer and quantum dots/glass structures, distinct optical properties have been shown. As a result, they are used in configurable lasers to support fluorescent materials in order to achieve maximum color emissions .The vapor-phase methods of synthesis of nanocrystals (quantum dots) are broadly based on the phenomenon of homogeneous nucleation and deposition of vapor-phase composition and formation of the solid particle which is to be restricted to nanoparticulated size and shape. The fundamental cause for the nucleation and deposition of vapor-phase composition is the thermal unitability of vapor-phase composition which is due to self-generated surrounding conditions. The whole process of synthesis of quantum dots occurs in a special type of chamber, also called process chamber, to alter the surrounding conditions such as temperature and pressure. The topic name ‘vapor-phase syntheses' indicates the involvement of the concept of supersaturated vapor. In the state of supersaturation, the vapor-phase composition is on the verge of transition to condense phase. The process of phase transition may also involve a chemical reaction. Since vapor-phase methods are performed in the process chamber, the state of the supersaturated vapor phase can be generated thermodynamically or by altering pressure . When thThe wet-chemical synthesis routes in colloidal solutions are well established, according to mainstream investigations in the field of quantum dots conducted on II-VI and IV-VI chalcogenide semiconductors. Group IV semiconductor nanocrystals (NCs), such as Si or Ge, and several III–V semiconductor nanocrystals (NCs), such as GaAs, GaN, and InAs, are difficult to make in solution due to their stronger covalent bonding and therefore higher melting points. As a second route, electron-beam lithography enables the fabrication of structures with nanometer dimensions but has a severe drawback of the low amount of serial lithographic methods. Therefore, the fabrication of well-deﬁned quantum dots must be conducted by various plasma processes. A further benefit of plasma synthesis over liquid phase methods is that the resulting material is devoid of ligands or surfactants. Depending on the application, these ligands may be added later. This makes it easier to integrate plasma-produced NCs into devices because it eliminates the need for the intermediate ligand exchanges that are normally needed for II-VI and IV-VI NCs. Ion sputtering and Plasma-Enhanced Chemical Vapor Deposition (PECVD) are two plasma-assisted techniques for producing quantum dots (QDs) , 17.One of the most cost-effective and efficient methods of fabrication of highly dense and homogeneous nanoparticles is the surface sputtering technique, which is broadly a Physical Vapor Deposition (PVD) of bulk semiconductors (cathode). It is a phenomenon in which the semiconductor surface  is bombarded by a beam of energetic particles of plasma, partially ionized gas (commonly Ar). This technique is also known as ion sputtering; this approach involves the utilization of phenomena occurring on the surfaces of bulk semiconductors exposed in the vacuumed chamber to the beam of energetic particles, especially ions. These ions are generated as a spatially clustered beam from gas discharged plasma, and for directed flow, they are accelerated to predetermined energies by the electric field, to have sufficient energy to get projected onto the substrate (Anode). The process of sputtering is commonly performed inside a special device known as an evacuated chamber. For ion beam milling and ion assistance, energy ranging from ∼100 eV to 5 keV is used . The spuAnother reliable and renowned synthesis method that has been gaining popularity recently due to its distinctive applications unlike the different stages of microelectronic circuit fabrication is the Plasma-Enhanced Chemical Vapor Deposition (PECVD) method. PECVD is a method for the fabrication of large-scale ICs (integrated circuits) and thin ﬁlm transistors. In Plasma-Enhanced Chemical Vapor Deposition, the reactive gases are decomposed via electrical discharge. This enables ﬁlm deposition at lower temperatures than CVD . In CVD,Due to their various beneficial properties, such as fluorescence, solvation in water, biocompatibility, low toxicity, compact size and ease of modification, rational scale-up processing, and versatile conjugation with other nanoparticles, quantum dots have risen as a potential material in a variety of biomedical applications. As a result, they have become a popular option for a variety of biomedical applications, including drug nanocarriers, therapeutic genes, photosensitizers, and antibacterial particles. Their capabilities must be proven in multifunctional diagnostic levels, cellular and bacterial bioimaging, and the advancement of theragnostic nanomedicine. They will be used shortly for identifying various types of cancer cells, atomic components of disease, and current drug action mechanisms, applying them to intracellular/extracellular considerations, and developing previously untested biochemical assay strategies.Currently, significant research is aimed to use the distinct optical properties of quantum dots in diagnostics and bioimaging. In the past decades, the most common method of labeling biological entities has been with organic fluorophores. But organic fluorophores have some limitations such as the instability of organic fluorophores when exposed to photoirradiation results in degradation and photobleaching over time. This implies that it does not continuously fluoresce for an extended period of time . TypicalOn the other hand, quantum dots have unique optical properties that make them ideal for biological imaging and tagging applications for several reasons . First, Quantum dots that have a near-infrared 650–900 nm) emission spectrum can be used to prevent any interference from the autofluorescence emitted by cells, hemoglobin, and water. The absorption coefficients and scattering effects of cells, hemoglobin, and water are lower in the near-infrared region. Intravital microscopy is usually performed with light, but imaging deeper tissues necessitate the use of near-infrared light. Moreover, under ultraviolet excitation, quantum dots are more photostable than organic molecules and have more saturated fluorescence [50–900 nmQuantum dots have promising applications in cellular labeling, deep-tissue imaging, and assay labeling due to their unique optical and surface properties, which make them an excellent alternative to conventionally used organic dyes. Besides, their unique optical properties make them excellent fluorescence resonance energy transfer (FRET) donors . FRET isThe bioassays and biomedical investigation can be broadly categorized into two parts in vitro and in vivo. In in vitro, bioassays are performed in a controlled and artificial environment whereas, in in vivo, biological systems or biomolecular bioassays are investigated in the presence of living organisms . The selIn the last two decades, and even currently, there has been a lot of research focused on targeted and rate-controlled drug delivery. One of the main concerns in medical treatment is the target and rate-controlled drug delivery to lower the side effects of conventional chemotherapy and other treatment methods. The targeting could be by utilizing pH-level maintenance paramagnetic nanoparticle controlling, ultrasonic waves interaction, and temperature control to localize and target the delivery of the drug to the diseased cells . Unlike The surface properties and high surface area of quantum dots make it suitable for conjugation with different kinds of biomolecules in order to localize the drug delivery to the target cell and can also be traced because of the unique optical and electrochemical properties of quantum dots. To reduce the toxicity of therapeutic agents, it is crucial to penetrate through the cell membrane for the targeted delivery of therapeutic agents or drugs. Also, the surface properties of quantum dots allow bioconjugation with some proteins and peptides, which are found to be capable of penetrating cell membranes. Cell-penetrating peptides (CPPs) are the most widely used biomolecules for penetration through the cell membranes and are compatible with most of the therapeutic agents, nucleic acids, proteins, and liposomes . CPPs arNumerous studies are being conducted by scientists across the globe to modify the genes, carry out gene replacement of the defective ones and novel ways to cure or prevent diseases, and improve health quality. In the past few decades, with the rising need for development in healthcare research in gene therapy, tremendous capabilities have been shown in a variety of applications. Its prominence has been evidently portrayed in several manifestations of developing concepts such as CRISPR-based genome editing and epigenetic research. The growing prominence of researches based on the science of metabolomics, proteomics, and transcriptomics will further expedite the imminent breakthrough of gene therapy , 26.Gene therapy has been quite instrumental in the treatment of numerous health issues, such as cancers or tumors, neurological malfunctions, dermatological disorders, cardiovascular disorders, ophthalmologic disorders, inner ear disorders, and transmittable diseases . HoweverGene therapy necessitates the use of multifunctionalized and biocompatible delivery platforms penetrating through the cell membranes. The optical and surface properties and high biocompatible surface area of quantum dots make it suitable for conjugation with different kinds of fictionalizers, so quantum dots can function as multifuctionalized delivery platforms for gene therapy . Owing tW, calculated through the expressionα and X are variables [Artificial intelligence provides new potentials for biomedical applications such as the prediction of patients' responses to therapies, the early diagnosis of a variety of disorders, and giving specific treatment options to the patients –46. The ariables .Artificial neural network (ANN) is applied for modeling the relationships between the in vitro data and in vivo effects  in asthmANN has been used widely to find cause-and-effect relationships and prediction of in vitro and in vivo data (IVIVC) correlations –53. The In , a multiANN and genetic algorithm are used to predict and optimize in vitro proliferation mineral medium for G × N15 rootstock . The autANN is used in  to prediAn ANN and pharmacokinetic simulations were used in the design of controlled release formulations with predictable in vitro and in vivo behavior .The optimized ANN model was used for the prediction of formulations based on two desired target in vitro dissolution-time profiles and two desired bioavailability profiles .In , the aut2+) imaging data as recorded from the primary visual cortex of a behaving mouse [In , the autng mouse , 60. Theng mouse . They foIn summary, AI-based models along with the conventional methods speed up the development and optimization of controlled release drug delivery systems . They alThe unique features of quantum dots which include a higher excitation coefficient broader absorption range, narrow and symmetric emission peak, and considerably good resistance to photobleaching, and many more have cemented the role of these versatile nanoparticles in the burgeoning fields of nanoscience and nanotechnology. Although quantum dots are not designed to assist everywhere, the application of quantum dots transcends beyond these artificial domains. In the future, quantum dots are going to be widely used as tools for diagnosing cancer cells. These dots can be intended for localized delivery and rate-controlled release of anticancer drugs or therapeutic agents to very specific parts of the body. Due to the property to target single organs, unlike other conventional drugs which come with unpleasant side effects, this makes them precise and more advantageous than other traditional processes like chemotherapy. These nanoparticles will also assist to categorize a wide spectrum of molecular mechanisms of various diseases as well as novel drug action mechanisms. They will be also used for observing and studying all the intracellular and extracellular activities.In comparison to the conventional use of organic fluorophore dyes, quantum dots such as CdSe have a higher quantum yield (approximately twenty times) and better resistance to photobleaching over time, making them more suitable for long-term imaging applications. Moreover, quantum dots are excellent for multiplex bioimaging which cannot be accomplished by organic fluorophore dyes; since quantum dots have a wide absorption spectral range, their emission spectrum wavelength can be readily altered in the range of 400 nm to 4000 nm by tuning their size. Quantum dots are more cost-effective for drug delivery than gold nanoparticles, and they can also serve as carrier modules of externally guided nanobots.However, quantum dots have also some drawbacks. In some in vitro research, degradation of quantum dots has been seen over time, which could lead to toxicities in the relevant living organisms. Quantum dots are extremely toxic and therefore must be necessarily encapsulated with a stable polymer shell. Additionally, in the core-shell quantum dot, the optical properties of the core can be obstructed by the shell and also make the regulation of the size of the quantum dots difficult.When conjugated with targeting agents and photosensitizers, a new category of mutable multifunctional nanoparticles can be developed that might prove as an aid to diagnostics or therapy. Also, the preparation of high-quality quantum dots from compounds that are nontoxic such as carbon and silicon might reveal a superior nanocrystal which might be of paramount clinical relevance. In imaging applications and bioanalytical chemistry assays, quantum dots have recently been shown to be a promising alternative to molecular fluorophores. But these innovative trends are evident that quantum dots have a futuristic scope and will become leading fluorescent reporters in biology and medicine over the next decade. A thoughtful, vigilant, and ground-breaking approach to deal with these nifty nanoparticles might bring unparalleled miracles in the field of healthcare research.