The focus of this prospective cohort study was to evaluate the risk factors of severe acute skin toxicity (grade ≥2) in 100 patients with breast cancer (BC) during radiotherapy (RT).The patients were evaluated weekly during RT and 3 months after treatment. The endpoint included the occurrence of skin toxicity grade ≥2, according to Radiation Therapy Oncology Group (RTOG). Survival analysis was conducted by univariate and multivariate Cox regression analysis.P = .042) was significantly associated with the early occurrence of skin toxicity, indicating a potential effect of chronotherapy related to this adverse event. In the univariate and multivariate analysis, skin phototype moderate brown  and dark brown or black  was significantly associated with the skin toxicity. Tangential field separation >21 cm , in women that were submitted to conservative surgery indicates indirectly that large breast size was also significantly associated with skin toxicity.In the multivariate analysis, RT in the afternoon (0–3 pm) (hazard ratios [HR] = 1.566, Women with large breasts and dark brown or black skin should be followed more carefully during RT, which should be undergone in the morning, especially when submitted to conventional RT techniques, common in developing countries. Clinical studies have indicated that the time of day that patients undergo RT can significantly influence the response to treatment and the severity of toxicities –10 and chronotherapy may have a potential effect to reduce skin toxicity.Skin toxicity is one of the major adverse local events of radiotherapy (RT), with a negative impact on the quality of life in women with breast cancer (BC) and which may lead to interruption of the treatment. In mammals, circadian rhythms have predictable fluctuations over a 24-hour period that affect behavioral, biochemical and physiological processes. The master circadian marker is the suprachiasmatic nucleus (SCN) that drives rhythmic cycles within extra- SCN neurons and peripheral tissues, such as skin. One of the functions of the SCN is to direct the cell cycle progression.,11 Each phase of the cell cycle corresponds to different degrees of radiosensitivity, with phase 2 and mitosis being the most radiosensitive, whereas the cells in the synthesis phase (S) are less sensitive to radiation. During treatment, radiation can damage normal cells that rapidly proliferate because of their high radiosensitivity, thus leading to adverse events. Such events can be minimized if the patient's treatment is performed during the time of day in which the non-neoplasic cells are in the S phase, that is, at which stage the cells are less sensitive to radiation.Chronotherapy considers the influence circadian rhythms have on the different types of treatments.Therefore, the focus of this prospective cohort study was to predict the risk factors of this adverse event, including the time of day in which women performed RT. We hypothesized that among the risk factors identified, undergoing RT in the afternoon (0–3 pm) would be one of them.2This prospective cohort study was conducted with BC women during RT, from April 2016 to June 2017, at a University Hospital.2.1Patients were selected from the daily list of the hospital and before starting their RT treatment and those that met the inclusion criteria were invited to participate.2.2 This selection process is illustrated in Flowchart 1  scale was used where1.No change over baseline;2.Follicular, faint or dull erythema/epilation/dry desquamation/decreased sweating;3.Tender or bright erythema, patchy moist desquamation/moderate edema;4.Confluent, moist desquamation other than skin folds, pitting edema;5.Ulceration, hemorrhage, necrosis.The irradiated area was recorded, using a Canon EOS Rebel T5i 18 to 55 mm camera, with a resolution of 18 MP, aiming to reduce subjectivity in the evaluation. The photos were taken so that all possible sites for the occurrence of skin toxicity could be recorded and maximum care was taken to maintain confidentiality. The photos were evaluated by 3 expert professionals that completed a questionnaire with the RTOG scale. The final score was considered the one where there was agreement between 2 or 3 of the professionals. The photos that could not be agreed upon by the 3 expert professionals were reviewed and a final consensus was reached.2.5 The body mass index (BMI) was grouped into eutrophic (18.4 <BMI <25 for patients up to 64 years of age and 22 ≤BMI ≤27 for patients 65 years of age or older) and no eutrophic (BMI ≤18.4 or BMI ≥25 for patients up to 65 years of age and BMI <22 or >27 for patients aged 65 years or older).,18The variables age, schooling, marital status, menopause  were analyzed. The cutaneous phototype was graded according to the Fitzpatrick classification and divided into 3 categories as described by.The number of nursing consultations during RT was grouped in greater than or equal to 5 consultations and less than or equal to 4. The reference for this grouping was that the patient should have the minimum number of 4 visits up to 21 days of treatment. Frequency of bra wear was grouped into 2 categories: not frequent, those that did not wear a bra during radiotherapy or used 1 for less than 2 weeks; and frequent, patients that wore bras for more than 2 weeks during radiotherapy.Treatment variables such as chemotherapy and type of regimen, surgery, and endocrine therapy were analyzed.2.6 and molecular subtype were defined according to the literature.The pathological stage2.7Tangential field separation  was classified in accordance with the percentile (pc) .Regarding the period of RT, the morning (07–10 am) and afternoon (0–3 pm) were considered. The number of fields of radiation has been grouped in 2 or more fields. Total dose was classified into 2 groups: less than 56  Gray (Gy); and greater than or equal to 56 Gy. Daily dose was also classified into 2 groups: 1.80 Gy and 2 Gy. The maximum radiation dose was defined according to the 75th percentile and grouped by greater than or equal to 110% and less than 110%.2.8This study was approved by the Human Research Ethics Committee (protocol number: 1348706/15) and was based on the standards of the Helsinki Declaration. All women signed a free and informed consent form and their privacy rights were observed.The sample size required for this study was determined using the G∗Power software, version 3.1. The calculations were based on cox regression, fixed models, with expected effect size of 0.15, an alpha level of 0.05, 93% power. Given the output parameter, a total sample of 100 women was required at final analysis.2.9Basic demographics, treatment and clinical characteristics of the cohort study were described using measures of central tendency and dispersion for continuous variables and proportions for categorical data.Survival analysis was conducted using the Kaplan–Meier method, to identify the cumulative incidence and the possible differences in the curves for each exposure group. The occurrence of skin toxicity  was considered as an event.P < .05 were considered statistically significant. Statistical analyzes were performed using SPSS software (IBM SPSS Statistics version 21).The univariate and multivariate Cox regression analysis were used to predict the risk of developing skin toxicity in BC patients. The results were expressed as the relative probabilities of an event with 95% confidence intervals (CI). Variables with p values ≤0.2 were inserted into the multivariate Cox and the stepwise approach  was conducted. Values of 3The total dose to the chest wall was 57.3 (95% CI 56.196–58.348) and a daily dose of 1.8 Gy in 37%, 2 Gy in 63%. 14% of the patients needed to interrupt treatment due to skin toxicity, with 7 days and 17 days being the minimum and maximum time. 73% received additional radiation dose, with 9 Gy (24%), 10 Gy, (48%), and 16 Gy (1%). The maximum treatment time was 50 days and the minimum was 27 days. The mean treatment time was 36.9 days (95% CI 35.70–37.88). The clinical and treatment characteristics are described in.After 42 days, 88.2% (n = 90) of the patients presented skin toxicity. The median occurrence was after 23 days (95% CI 21.17–24.83), corresponding to a mean radiation dose of 38.85 Gy (95% IC 30.00–46.80) , tangential field separation >21 cm , phototype moderate brown , dark or black  and those who used a bra (for more than 2 weeks during RT)  were significantly associated with the early occurrence of skin toxicity. In the multivariate analysis RT in the afternoon , tangential field separation >21 cm , moderate brown , dark or black  were significantly associated with the early occurrence of skin toxicity (Table Regarding skin toxicity (grade ≥2) risk factors, in the univariate analysis, maximum radiation dose ≥110% . Regarding BMI, non-eutrophic women presented a greater chance of developing skin toxicity  in the univariate analysis, however without statistical significance. Obesity and having large breasts are considered risk factors for the occurrence of skin toxicity.–6 Moody et al  suggests that more serious toxicities in patients with large breasts are related to localized hot spots and heterogenic dose of radiation, since such hot spots are related to the maximum prescribed dose. In the present study, women who were treated with a maximum dose greater than or equal to 110% had a risk of developing skin toxicity earlier . One possible aspect may be related to the existence of a higher percentage of mammary adipose tissue. Irradiated adipose tissue is an important source of autotaxin secretion that produces lysophosphatidic acid. It promotes a vicious inflammatory cycle with nuclear factor kappa B activation, Cyclooxygenase 2 expression, and increased signaling by secretion of inflammatory cytokines, chemokines and growth factors, including transforming growth factor alpha , platelet-derived growth factor and autotaxin. Such inflammatory response is associated with cutaneous toxicities.In the present study, having large breasts  and being submitted to conservatory surgery, was a risk factor for the development of early skin toxicity in both univariate and multivariate analysis  when compared to phototype II, III, and IV. Our results are in agreement with the literature.,4,35 The dark pigment that gives the dark coloration of black or dark brown skin is due to the presence of more eumelanin. The production of this type of melanin occurs when alpha- melanocyte stimulating hormone  binds to the melanocortin 1 receptor. The high frequency of the melanocortin 1 receptor Single Nucleotide Polymorphism, specifically mutations in the R160 W allele, was associated with the presence of severe acute skin toxicity, suggesting a relationship between dark skin color and the presence of this adverse event. Genetic and molecular markers may also explain this relationship. Blaszyk et al observed differences in the pattern of p53 mutations acquired by black women with breast cancer when compared to white women. This gene is related to the changes in the cell cycle due to ionizing radiation, with consequent modifications in the epithelial maturation process of this specific population.In our study, another factor that presented statistical significance for the occurrence of early skin toxicity was the phototype V or VI  in approximately 4 weeks or more (a radiation dose of between 30 and 40 Gy). Such data is extremely important, since it proves the need to adopt preventive measures and health education actions that have a significant impact before 23 days of treatment, that is, with an average radiation dose of approximately 40 Gy.Finally, we also identified that within 23 days, 50% of patients submitted to RT had a probability of skin toxicity occurrence, that is, with a mean radiation dose corresponding to 38.85 Gy. Our data is similar to the literature, conventional regimens without 3D planning is still a reality in developing countries such as Brazil. Thus, the results of the present study may contribute to public health care, and should be considered in the clinical practice of hospitals that follow the Brazilian Unified National Health System and other similar health care systems from developing countries.Despite advances in the field of RT, with the adoption of high-tech devices, providing more effectiveness and consequently a reduction of adverse events,Some limitations should be considered such as the small amount of variability in the sample included in the present study, specifically in relation to factors like smoking, chemotherapy, hormone therapy, radiotherapy scheme used. A secondary limitation is that it was not possible to evaluate patients undergoing more advanced RT techniques such as Intensity Modulated Radiotherapy. The strength of the study resides in its comprehensive nature and the quality of the data because symptoms were collected weekly during and also after the end of the radiation treatment. The evaluation of skin toxicity was realized to reduce subjectivity, through the photographic registry and independent evaluation by three expert professionals.Considering that the period of the day when BC patients are treated is the only modifiable risk factor, it is suggested that those with large breasts and dark brown or black skin color, who had a higher risk of developing skin toxicity earlier, be treated in the morning (07–10 am), specifically those from developing countries, such as Brazil, which in many public hospitals still use conventional techniques.Conceptualization: Marceila de Andrade Fuzissaki, Paula Philbert Lajolo Canto, Yara Cristina de Paiva Maia.Data curation: Marceila de Andrade Fuzissaki, Yara Cristina de Paiva Maia.Formal analysis: Marceila de Andrade Fuzissaki, Carlos Eduardo Paiva, Marco Antonio Oliveira, Marcelo Almeida Maia, Yara Cristina de Paiva Maia.Funding acquisition: Marcelo Almeida Maia, Yara Cristina de Paiva Maia.Investigation: Marceila de Andrade Fuzissaki, Yara Cristina de Paiva Maia.Methodology: Marceila de Andrade Fuzissaki, Paula Philbert Lajolo Canto, Yara Cristina de Paiva Maia.Project administration: Marceila de Andrade Fuzissaki, Yara Cristina de Paiva Maia.Supervision: Marceila de Andrade Fuzissaki, Yara Cristina de Paiva Maia.Validation: Marceila de Andrade Fuzissaki, Yara Cristina de Paiva Maia.Visualization: Marceila de Andrade Fuzissaki, Marcelo Almeida Maia, Paula Philbert Lajolo Canto, Yara Cristina de Paiva Maia.Writing – original draft: Marceila de Andrade Fuzissaki, Carlos Eduardo Paiva, Marco Antonio Oliveira, Marcelo Almeida Maia, Paula Philbert Lajolo Canto, Yara Cristina de Paiva Maia.Writing – review & editing: Marceila de Andrade Fuzissaki, Carlos Eduardo Paiva, Marco Antonio Oliveira, Marcelo Almeida Maia, Paula Philbert Lajolo Canto, Yara Cristina de Paiva Maia.


Corneal dystrophies are a group of rare, inherited disorders that are usually bilateral, symmetric, slowly progressive, and not related to environmental or systemic factors. The majority of publications present the advanced form of the disease with a typical clinical demonstration. The initial signs and symptoms of different epithelial and stromal corneal dystrophies are not specific; therefore, it is very important to establish the early characteristic corneal features of these disorders that could guide the diagnostic process.CHST6 gene sequencing. The early corneal characteristic features of MCD, established based on the findings of this case report, include corneal astigmatism (not specific), diffuse corneal thinning without a pattern of corneal ectasia (specific), and characteristic features on confocal microscopy (specific), including multiple, dark, oriented striae at different corneal depths.The main purpose of this study was to report the differential diagnosis of a pediatric patient with bilateral anterior corneal involvement suspected of corneal dystrophy. An 8-year-old male patient presented with asymptomatic, persistent, superficial, bilateral, diffuse, anterior corneal opacities. Slit lamp examination results were not specific. Despite the lack of visible stromal involvement on the slit lamp examination, corneal analysis based on confocal microscopy and optical coherence tomography revealed characteristic features of macular corneal dystrophy (MCD). The diagnosis of MCD was confirmed by The clinical examination should be complemented with corneal imaging techniques, such as confocal microscopy and optical coherence tomography. In patients suspected of corneal dystrophy, genetic testing plays an important role in establishing the final diagnosis. Macular corneal dystrophy  is a stromal corneal dystrophy indicated as category 1 according to the International Committee for Classification of Corneal Dystrophies IC3D)  [D  and to the Eye Bank Association of America (EBAA) , 8. In tCHST6), encoding corneal N-acetylglucosamine-6-sulfotransferase (C-GlcNac6ST), have been linked to MCD and further reported in patients originating from populations of different regions throughout the world. There is mutational heterogeneity and the predominance of missense mutations, accounting for approximately 50 % of MCD cases) whereas nonsense mutations, deletions, insertions or indels account for approximately 30 % of MCD cases [The main pathogenetic factor of MCD is the progressive intra- and extracellular accumulation of glycosaminoglycans in stromal keratocytes, Descemet membranes and endothelial cells, leading to the loss of transparency in the corneas of affected patients –3, 13. MCD cases –16.Historically, the confirmation of the diagnosis of MCD was based on the presence of basophilic granular material, which stains positively with periodic acid Schiff, Alcian blue, metachromatic dyes and colloidal iron intra- and extracellularly within the corneal stroma, Descemet membrane and endothelial cells . The broConfocal microscopy is widely used for analyzing the in vivo microscopic structure in several clinical conditions, such as infectious keratitis, dry eye syndrome, corneal dystrophies and degenerations , 18. ChaAS OCT enables in vivo cornea and other anterior chamber structure imaging with an axial resolution from 18 μm with time domain OCT (TD OCT) and 5.0 μm with spectral domain OCT (SD OCT) to 2,0 μm with high definition OCT (HD OCT). The main pathological features of advanced MCD described in previous studies include general increased reflectivity throughout the corneal stroma, irregularity of the anterior stromal border from the epithelium side, diffuse areas of hyperreflectivity in Bowman’s layer caused by corneal deposits and a noticeable layer of increased reflectivity in the posterior, peripheral corneal part –22.For patients with a suspicion of corneal dystrophy, the diagnostic flow includes a detailed familial history, the onset and characterization of signs and symptoms as revealed on the slit lamp exam, and corneal morphology and topography analysis using an available imaging system, such as optical coherence tomography, Scheimflug imaging, Orbscan or confocal microscopy. Finally, molecular diagnosis is becoming increasingly important for establishing the correct diagnosis in challenging cases, as is the development of novel genotype-specific treatments.Considering the challenges in corneal dystrophy differential diagnosis, especially in pediatric populations, we would like to report a pediatric case of macular corneal dystrophy in which the final diagnosis was established based on detailed corneal imaging data confirmed by genetic testing. The case report is part of a study approved by the Ethics Committee of the Medical University of Silesia, Katowice, Poland . The patients’ parents signed an informed consent form before any study procedure.An 8-year-old male patient was referred to the Chair and Clinical Department of Ophthalmology, School of Medicine with the Division of Dentistry in Zabrze, Medical University of Silesia in Katowice by a general ophthalmologist due to persistent, superficial corneal opacities revealed when diagnosed with the mild conjunctivitis two months earlier. The conjunctivitis was treated with ofloxacin eye drops (3 mg/ml) four times daily and resolved after one week. No specific testing, such as cell culture, immune assays or polymerase chain reaction (PCR), was performed at the acute stage of the conjunctivitis. Due to the persistent superficial corneal abnormalities in both eyes and a suspected diagnosis of multiple subepithelial corneal infiltrates (MSIs) caused by epidemic keratoconjunctivitis (EKC), the patient was administered hydrocortisone eye drops (3.35 mg/ml) twice daily for two weeks and once daily for one week. There was no significant difference in corneal status; therefore, the patient was referred to our clinic. On examination, he reported no ocular complaints. He had no significant medical or drug history, as well as no previous ocular disease in either eye, except for the reported conjunctivitis. The patient did not have a relevant family history.The best corrected visual acuity (BCVA) was right eye (RE) (cc + 6.0 Dsph − 4.5 Dcyl axis 170°) 1.0; left eye (LE) (cc + 6.0 Dsph − 3.5 Dcyl axis 175°) 1.0. The ocular refraction after tropicamide cycloplegia (1 % tropicamide eye drops administered 3 times every 15 min) was RE, + 7.0 Dsph − 4.75 Dcyl axis 170°; LE, + 7.0 Dsph − 4.0 Dcyl axis 175°. The intraocular pressure (IOP) in both eyes was 14 mmHg. The axial length was 20.94 mm for the right eye and 21.12 mm for the left eye as measured by an IOL Master . On slit lamp examination, multiple diffuse, grayish, indistinct, superficial corneal opacities extending from limbus to limbus accompanied by subepithelial haze were present. The severity of the corneal changes was comparable between eyes  revealed abnormalities regarding the anterior topography and pachymetry map, as did select parameters from Fourier indices analysis. The pachymetry map revealed bilateral, general corneal thinning. The corneal apical thickness (CAT) of the right eye was 360 μm, and that of the left eye was 365 μm. The thinnest portions of the cornea were 352 and 350 μm thick, respectively. The location of the thinnest corneal point was the inferotemporal region in both eyes. Keratometric and posterior topography maps confirmed the presence of with-the-rule astigmatism . The corneal shape was characterized as prolate, both for the anterior and posterior surfaces  within 9.0 mm was 0.54 and 0.5 in the RE and 0.51 and 0.4 in the LE, respectively). Anterior and posterior elevation maps showed a typical pattern in which the apex demonstrated warm colors above the BFS  with a slightly elevated isthmus that joined the central cornea from the temporal periphery. Right-left mirror symmetry was present. Three and six millimeter Fourier indices analysis revealed abnormalities regarding two parameters: regular astigmatism on the anterior and posterior surfaces and asymmetry on the anterior surface. The results of 6 mm keratometric and real higher-order index analysis were borderline in both eyes. The Ectasia Screening Index (ESI), which is a parameter used in the detection of corneas with ectasia patterns implemented in SS OCT software, was 0 % in both eyes. The results of the above anterior and posterior corneal surface analyses and the pachymetry map are presented in Fig. A Heidelberg Retina Tomograph 3 Rostock Cornea Module  was used for the in vivo assessment of the detailed corneal morphology after topical instillation of 0.5 % proparacaine hydrochloride  eye drops. The epithelial layers were of normal morphology. Starting at the level of Bowman’s layer, multiple, differently oriented dark striae were visible. The morphology of the striae changed at different corneal depths. The striae were especially prominent, multilayered, dark and thick at depths of 90–150 μm, becoming less evident at increasing depths. The keratocytes and the intercellular space had a granular, hyperreflective appearance throughout the whole stroma. The corneal endothelial morphology was not documented due to poor cooperation of the child during this invasive, uncomfortable examination. The results of confocal microscopy are presented in Fig. Based on the corneal morphology examination, a suspected diagnosis of stromal corneal dystrophy was made. The majority of corneal dystrophies are characterized by familial occurrence; therefore, the parents were carefully examined to identify possible corneal abnormalities. The examination did not reveal any changes. The familial history also did not reveal any significant ocular diseases or parental consanguinity. Accordingly, a diagnosis of autosomal recessive stromal corneal dystrophy, mainly macular corneal dystrophy, was suspected. The patient could also potentially be the first affected member of the family in case the corneal dystrophy is autosomal dominant.CHST6, TGFBI, KRT3, KRT12, COL8A2, SLC4A11, TACSTD2, UBIAD1, VSX1, and ZEB1. The next-generation sequencing (NGS) technique was performed with the SeqCap EZ Hyper Cap protocol and a NimbleGen SeqCap EZ probe kit  using a NextSeq sequencer by Illumina . NGS analyses with a mean read coverage of at least 40× were considered successful. The test result was confirmed using the Sanger reference method, described in detail in our previous publication [CHST6 gene, the reference sequence with accession number NM_021615.4  was used. The known homozygous, pathogenic variant c.1 A > T (p.M1?) was found following CHST6 gene analysis for our patient (proband). CHST6 gene sequencing for both parents revealed the same variant in a heterozygous state . HOAs of the total cornea and anterior and posterior surfaces were reported to be larger in subjects with stromal corneal dystrophies than in normal control subjects , 33. TheThere are few case reports on the cooccurrence of keratoconus and MCD , 38. In CHST6 gene sequencing in our patient, thus confirming a diagnosis of MCD. Alterations of the first codon have also been reported in Polish, Czech, German and Turkish populations [According to the American Society of Ophthalmology guidelines, genetic testing should be offered to patients with clinical findings suggestive of a Mendelian disorder, whose causative gene(s) have been identified , 40. Theulations , 41–43. ulations . Currentulations –46.The main importance of this case report is in defining the early characteristic features of MCD, despite the absence of characteristic corneal abnormalities on slit lamp examination. The main limitations are the difficulties in performing high-quality slit lamp and confocal microscopy scans in an 8-year-old patient. Additionally, the influence of environmental factors and tear film disturbances could interfere with the OCT Fourier indices results.To conclude, the initial signs and symptoms of different epithelial and stromal corneal dystrophies are not specific; therefore, it is very important to establish early characteristic corneal features that could guide the diagnostic process. The clinical examination should be complemented with corneal imaging techniques, such as confocal microscopy and optical coherence tomography. Early corneal characteristic features of MCD, established according to the findings of the case report, include corneal astigmatism (not specific), diffuse corneal thinning without a pattern of corneal ectasia (specific), and those obtained on confocal microscopy (specific), including multiple, dark, oriented striae at different corneal depths. In patients suspected of corneal dystrophy, genetic testing plays an important role in establishing the final diagnosis and may provide encouraging results for future gene therapy.


Plant breeders’ knowledge of precise traits preferred by variety users would accelerate varietal turnover and widen adoption of newly developed maize varieties in Ghana. The objective of this research was to provide empirical evidence of trait preferences of farmers and other actors in the maize value chain in northern Ghana, based on which research strategies for maize improvement could be formulated. Participatory rural appraisal was conducted in 2016 to determine key traits preferred by maize value chain actors across the three regions in northern Ghana. A total of 279 maize value chain actors were interviewed. Different scoring and ranking techniques were used to assess the maize traits preferred by the different actors. Participatory variety selection trials were also conducted in the Tolon, West Gonja, Binduri, and Sissala East districts in northern Ghana from 2014 to 2016. The mother-baby trial approach was used to evaluate eight hybrids with 3000 farmers. Data on yield and agronomic performance of the hybrids and farmer’s selection criteria were collected. Data analyses were performed using GenStat Edition 16 and SPSS Edition 20 statistical packages. The participatory rural appraisal method identified farmers, input dealers, traders, and processors as the primary maize value chain actors in the study areas. Trait preferences of the different actors overlapped and revolved around grain quality including nutritional value, and stress tolerance and grain yield. Results of the participatory variety selection study revealed that across districts, farmers preferred high-yielding varieties with multiple cobs per plant, white grain endosperm color, and bigger and fully filled cobs. For the first time, our holistic assessment of the trait preferences of key actors of the maize value chain in northern Ghana revealed a comprehensive list of traits, which could be used by breeders to develop varieties that may be preferred by all value chain actors in northern Ghana.The online version contains supplementary material available at 10.1007/s13593-021-00708-w. This yield is far below the international output of maize , consumers, and other actors at the early stage of cultivar development  and participatory variety selection (PVS) methods were conducted to determine trait preferences of maize value chain actors as well as farmers’ selection criteria across the three regions of northern Ghana ; organoleptic and grain quality traits , and others (market price of grains and access to improved seeds). The actors were asked to rank the traits according to their own preferences giving reasons for their choices. The traits listed by the actors were also used to design a questionnaire, which was later used during formal interviews with farmers, traders, input dealers, and processors.Focus group discussions were conducted to collect general information about the existing maize production system in selected communities. The data collected described the production and marketing activities of the actors, their role in the value chain, and the impact of the maize production system on livelihood and welfare outcomes. During the focus group discussions, the different value chain actors identified were asked to list the traits/characters that were considered while selecting maize varieties for their enterprises. The traits listed by the actors were grouped into four main categories as physical traits  per plant, and cob fill); stress response traits . The mother-baby trial approach involving researcher-managed mother trials and farmer-managed baby trials was used. Four mother trials were conducted in four farming communities across the four districts each year. The mother trials were laid out using the randomized complete block design, with each site as a replicate. In the mother trials, all the eight hybrids were planted together with two varieties nominated by farmers (farmers’ varieties 1 and 2) as local checks. In the baby trials, the eight hybrids were grouped into two sets with each set evaluated separately together with local check varieties nominated by collaborating farmers. Four baby trials were conducted in each district per year. With the help of local agricultural extension officers, lead farmers were selected from farmer-based organizations (FBOs) to manage the baby trials. The lead farmers were selected based on their experiences in maize production, access to land, and their ability and willingness to disseminate information on the target hybrids to other farmers. A plot size of 10 m × 10 m was used. Spacing between rows was 75 cm and spacing within plants was 40 cm. A compound fertilizer, NPK 15-15-15, was applied at the rate of 60 kg N ha−1, 60 kg P2O5 ha−1, and 60 kg K ha−1 at 2 weeks after planting (WAP). The plots were top-dressed with 30 kg N ha−1 at 4 WAP. Weed control was manually done at all sites when necessary to keep the plots free from weeds. All the trials were conducted under rainfed conditions.Participatory variety selection trials involving eight elite early-maturing maize hybrids were conducted in fourteen communities in Tolon, Sissala East, West Gonja, and Binduri districts in northern Ghana  from the base of the plant to the node bearing the flag leaf. Ear height was measured as the average height of the ear in centimeters (cm) from ground level to the node bearing the uppermost ear. Plants harvested per plot were measured as the total number of plants harvested per plot. Ears harvested per plot were measured as the total number of ears harvested per plot. The number of root-lodged plants was recorded as the number of plants tilted more than 30̊ angle from the ground and was scored on a scale of 1–5, where 1 = no lodging of plants; 2 =more than 20% of plants lodged; 3 = more than 40% of plants lodged; 4 = more than 60% of plants lodged; and 5 = more than 80% of plants lodged. Stalk lodging referred to the number of plants with broken stalks below the ear or the stalk bending more than 45̊ angle from the upright position. The number of stalk-lodged plants was scored on a scale of 1–5, where 1= no lodging of plants; 2=more than 20% of plants lodged; 3= more than 40% of plants lodged; 4=more than 60% of plants lodged, and 5=more than 80% of plants lodged. Field weight was measured as the weight of cobs per plot measured in kilograms. Moisture content of the grain was measured with a moisture tester (agraTronix™ MT-16) at harvest and recorded as a percentage of the grain harvested at physiological maturity. Plant aspect was scored on a scale of 1–5. Scoring was based on the assessment of overall architecture of plants in a plot as they appealed to sight, where 1 was excellent overall phenotypic appeal, 2 was very good overall phenotypic appeal, 3 was good overall phenotypic appeal, 4 was poor overall phenotypic appeal, and 5 was very poor overall phenotypic appeal. Ear aspect was scored on a scale of 1–5, where 1 was excellent with no disease/insect damage, large cobs, uniform ears, and fully filled grains, 2 was good ear with no disease/insect damage and fully filled grains, and one or two irregularities in cob size, 3 was mild insect damage, with no disease, fully filled grains, and one or two irregularities in cob size, 4 was severe disease/insect damage, with scanty grain filling, few ears, and non-uniformity of cobs, and 5 was only one or no ears. Plant vigor of all entries per plot was scored at 4, 6, and 8 WAP using a scale of 1–5, where 1 was weak plants, 2 was less vigorous plants, 3 was fairly vigorous plants, and 4 was more vigorous plants. A shelling percentage of 80% was assumed for varieties per plot. Grain yield calculated from field weight was converted to kilograms per hectare. Grain yield was adjusted to 15% moisture content. Ears per plant were obtained by dividing the total number of ears harvested per plot by the total number of plants harvested per plot.At tasseling, 20 male and 20 female farmers from each participating community were invited to the mother trials to score for early maturity and drought tolerance. Also, the farmers were invited at harvesting, to score for cob size, grain filling, number of ears per plant, grain color, and grain yield. At each visit, the farmers were asked to rank the overall performance of the varieties based on their own indigenous criteria and preferences using a scale of 1–5, where 1 was least preferred, 2 was less preferred, 3 was fairly preferred, 4 was more preferred, and 5 was most preferred. Over 3000 farmers participated in the mother-baby trials from 2014 to 2016.n. The mean rank score for each preferred character was computed and the factor with the least score was ranked as the least preferred quality attribute or trait while the highest score was ranked as the most preferred. The total rank score computed was then used to calculate the coefficient of concordance (W), which measured the degree of agreement among the respondents in the rankings. The “W” was estimated using the relation proposed by Tetteh et al.  was tested for significance in terms of the chi-square distribution.Principal component analysis (PCA) was also performed for data reduction purposes. The PCA was done to identify the most important traits based on their magnitude of contributions to the total variation in the combined data sets for farmers and input dealers, and traders and processors. The PCA was performed using the relations by Anderson  as follox be a p-component random vector with mean vector εx = μ and covariance matrix ε(x − y)(x − y)′ = ∑. The variance of a linear combination γ′x is given by:Let γ′γ = 1 which has maximum variance may be called the first principal component of x. The linear combination uncorrelated with the first principal component and similarly normalized which has maximum variance may be called the second principal component. The other p − 2 principal components were similarly defined.The linear combination normalized by To obtain precise linear combinations, we used the characteristic roots and vectors of ∑.δ1 ≥ … ≥ δp > 0 be the p characteristics roots of ∑(assumed to be positive definite). They are the roots of:Let γ1, …, γp are the corresponding normalized characteristic vectors; they satisfy:Let th Edition  across the study areas were headed by males Table . Female Banku, Tuo-zaafi, Kenkey, porridge, and Kpaakpulo or in raw form as floor and dough for sale.Input dealers from the sampled population across the three regions of northern Ghana were males who were married and heads of their households. The average age of input dealers across the sampled population was 39 years Table . The majKendall’s coefficient of 0.8 was obtained for farmers. This indicated that 80% of the survey respondents agreed with the ranking of traits preferred by maize farmers in the sampled population. The first most preferred trait by farmers was grain yield Table . VarietiStriga resistance (ranked 16th) (Table The period of maturity of a maize variety was ranked the third most important trait by the farmers interviewed Table . Early-mh) Table . Varietih) Table . Northerh) Table . Ellis-Jh) Table  identifih) Table  revealedh) Table .In the study areas, the most preferred traits by input dealers, in order of importance, were grain color, days to maturity, grain yield, access to seed, and grain size. Input dealers preferred white endosperm varieties, early-maturing varieties, and high-yielding varieties with grain of large size. Kendell’s coefficient of concordance indicated that 60% of the sampled input dealers agreed with each other on the ranking of the traits Table . The traAbout 50% of traders and 40% of processors in the sampled population agreed with the ranking of the traits they prefer, respectively Fig. . For traMarket price of grains was identified as an important criterion used by input dealers, processors, and traders in the study areas in the selection of maize varieties. It had the highest rankings among processors (second important trait), while traders and input dealers ranked it as the third and sixth important trait, respectively Tables . FluctuaStriga resistance, cob size, market price of grain, days to maturity, grain color, nutritional value, grain yield, grain shape, grain size, and plant height  having eigenvalue greater than 1 . The 8 Pht Table . This ree et al. , droughtThe PCA of traits preferences of both traders and processors revealed 4 principal components (PCs) having eigenvalues greater than 1 . The 4 PThe mean grain yield of the varieties across mother and baby trials was 2.8 t/ha. The top three yielding hybrids across the four districts were EYH-29, EYH-42, and EYH-19, respectively. EYH-29, EYH-42, and EYH-19 out-yielded the best local check (Farmer variety 2) by 45.3%, 34%, and 20.8%, respectively  and EWH-29 (CSIR-Similenu) that are more suited to the preferences of actors in northern Ghana.The value chain actors identified in the study areas were primarily farmers, input dealers, traders, and processors. The commonest and most important traits considered by all four actors when selecting maize varieties were grain color, grain size, and market price of grains, nutritional value, and consistency of cooked meals. According to the four actors, these are the traits consumers look for in a maize variety, and therefore, they control the marketing of maize grains and its products in their communities. In addition to the above traits, farmers, and input dealers also considered drought tolerance, ESM 1(DOCX 22.7 kb)


Attachment systems (AS) enhance retention and stability by anchoring the overdentures to implants. Since 2002, the McGill consensus statement recommends the 2-implant-retained overdentures as the standard choice for edentulous mandible (2-IRMO). Considering the large number of AS available, it remains difficult for a practitioner to make a reasoned choice. A systematic review was conducted in PubMed/Medline and carried out independently by three authors, on retention, wear, and maintenance of AS used clinically or in vitro specifically for 1- or 2-IRMO. The 45 selected studies include 14 clinical and 31 in vitro studies. The risk of bias was evaluated according to the revised Cochrane risk of bias tool for randomized trials (RoB 2). The initial retention force of the cylindrical system is higher than the ball system. The retention loss, related to the wear of the retention device, is responsible for the most common need of maintenance, requiring activation or replacement. Plastic retention devices wear out faster and more significantly than metal ones, implying a worse time behavior of cylindrical systems, but their maintenance rate is similar. Neither system appears categorically superior. Cylindrical systems provide higher initial retention than ball ones; this advantage reduces over time with wear without affecting their need for maintenance. Different attachment systems (AS) with varied prosthodontic designs  and materials  are used as primary or secondary retention devices in removable mandibular overdenture, retained or stabilized on implants ,3,4,5,6.All AS for IRMO are composed of one male part, the patrix—an abutment connected to the implant—and one female part, the matrix—composed of a housing included in the intaglio surface of removable denture containing a replaceable retention device (RD) . When pa® Plus  , “implant attachment*” OR “overdenture attachment*” OR “attachment system*” OR “stud attachment*” OR “resilient attachment*” OR “spherical attachment*” OR “ball attachment*” OR “cylindrical attachment*” OR “locator attachment*”, maintenance OR complication* OR prosthodontic* OR prosthetic* OR prosthes* OR retention OR wear, “implant stabilized overdenture*” OR “implant retained overdenture*” OR “implant supported overdenture*”. The search included language (English) and publication status restrictions (Abstract) with date limitation (1996–2021). In addition, a manual screening was carried out among the references of selected articles to gather further relevant papers. Three review authors  assessed studies independently for eligibility by initially screening successively titles and abstracts . Then, t(i)in vitro studies reporting on initial retention, retention loss, and wear of real or simulated 1- or 2-IRMO using stud-shaped BAS or CAS,(ii)clinical studies  reporting on maintenance of AS  in 1 or 2-IRMO regardless of follow-up time.Different inclusion criteria have been used:(i)maxillary overdenture,(ii)partial dentures,(iii)fixed overdentures,(iv)overdentures on remaining natural teeth or roots,(v)more than two implants,(vi)implant splinting,(vii)other AS ,(viii)anecdotal BAS and CAS.The exclusion criteria were:Comparative studies were rejected if only one type of BAS or CAS was used versus other AS. Case reports, reviews, and short communications were rejected.(i)the initial retention and its evolution over time of clinical use (Newton (N), loss of retention (%)), in correlation with the observed wear patterns  and the dimensional changes (μm) of AS components,(ii)the maintenance follow-up (frequencies: months/years), and maintenance procedure of AS (activation/replacement).The primary outcome measures concerned:(i)the effects of denture cleansing solutions on the retention and wear of AS,(ii)the overdenture maintenance ,(iii)the interimplant distance (mm) or angulation (°) and their impact on primary outcomes.The secondary outcomes were to report:For eligible studies, data were extracted and collected in an Excel spreadsheet by one review author (R.W.) and checked by two others  independently. In case of disagreement, a consensus was obtained with discussion between the authors. Finally, 45 articles have been identified out of a total of 1134 selected among which 14 clinical and 31 in vitro studies.The quality assessment of each clinical and in vitro study, based and adjusted from the revised Cochrane risk of bias tool for randomized trials (RoB 2)  was indeFor the clinical studies, the risk of bias (RoB) was assessed by the following items: randomization process, deviations from intended interventions, missing outcome data, measurement of the outcome, selection of the reported result, and other biases such as the presence of a control group, description of inclusion criteria, the status of the maxillary arch (complete edentulous and overdenture), years of follow up , follow-up planning. For other biases, the study received a ‘yes’ if at least 4 parameters were respected over 5, a ‘middle’ if only 3 parameters were respected and a ‘no’ otherwise. RoB 2 criteria were adapted for in vitro studies, assessed by the following items: randomization process, blinding of the test operator, post-processing of experimental data , and detailed protocol for retention and wear measurements.Each item was evaluated following RoB 2 recommendations. Finally, to assess the overall RoB, a study with at least one ‘no’ was classified as ‘high RoB’, a study with ‘unclear’ or ‘middle’ for one or more items was classified as ‘unclear RoB’ . A study with ‘yes’ in all domains was classified as ‘low RoB’.Among the 45 selected studies, 25 studies showed a low RoB and 13 moderate RoB. Only 7 clinical studies exhibited a high RoB, primarily due to their lousy score for randomization. In vitro studies were poorly scored for the blinding of test operators, but it did not impact their overall RoB .According to the aim of this SR, the results are presented in four parts: (i) the initial retention of BAS and CAS, (ii) the retention loss and wear of AS correlated to the prosthodontic maintenance; the influence of implant parameters (iii) and experimental conditions (iv) on the retention, wear, and maintenance. Finally, paragraph (v) exposes the limitations of our study and, in particular, the difficulty of comparing studies directly because of the variability in their protocols and reported results.Retention is defined as the maximum force developed until dislodgement of the denture from its mucosal and/or implants bearing surfaces. It represents the mechanical resistance to displacement along the insertion axis opposite to denture insertion . Retenti® and 13.12 and 24.03 N for ERA® [BAS show retention forces in agreement with manufacturers’ data, in the range of 2–16 N for 1-IRMO. However, regarding CAS for 1-IRMO, a wide range of retention forces is available through the different color-RD between 3.84 N and 16.6 N for Locatorfor ERA® ,23 . Higher retention may be related to unwanted misalignment between implant axes or between implants and insertion axes due to inaccuracies in implant positioning and in controlling the direction of dislodgment in vitro. Despite many studies  over BAS  even if the values vary between studies. This could be explained by larger friction surfaces observed in CAS between the cylindrical abutments and the RD compared to the linear contact located at the ball’s equator in BAS. Three contradictory studies found greater retention for BAS with plastic RD [®. These results could be explained by the use of a larger implant (8 mm) with AS diameter (5.9 or 7.9 mm) [® and 33.5 ± 9.77 N for Locator®) [Several in vitro studies have compared the initial retention force of BAS and CAS. Five studies ,21,32,36astic RD ,33 or meastic RD  compared 7.9 mm) , anecdotocator®) .®) is more significant than BAS, even if the tested RD and the experimental conditions vary between studies. However, this superiority does not seem to be felt clinically, according to Krenmair et al. that showed similar patient satisfaction for the two types of attachment during 3 months of wearing [In conclusion, the few comparative in vitro studies agree that the initial retention force of CAS  with different numbers of cycles per day: 3 ,40, 4 1,41,42 orWear is defined as material loss due to contacts between the matrix and the patrix, which increases the gaps between the different parts ,41. In tConcerning BAS, retention is ensured mainly by the friction between two metallic surfaces  and sometimes between metallic and polymeric surfaces . Wear including abrasion and scratches can exceptionally affect the patrix—diameter reduction up to 25% observed with an anecdotic titanium RD after 5000 IRC (3 years) —but affeClinical studies about BAS showed that wear of the precious alloy RD in contact with the titanium alloy ball abutment generated blunt lamella edges with a loss of RD thickness  ,44, and ® AS with the presence of mineral deposits coming from the titanium alloy abutment [® RD (loss of substance and surface irregularity) [® nylon RD (>5.0% surface smoothing) [® or CM Loc®) is not well established: one in vitro study showed severe deformation after 30,000 IRC (16 years) [®, Locator® and CM Loc® RD decrease significantly in long term retention, and in particular for Locator®  compared to CM Loc® (32 to 47%) after 30,000 IRC (16 years) [® RD (85% after 1000 IRC/1 year) [®, a significant decrease in retention is even observed during the first 10 to 20 IRC, but retention loss remains not significant after 100,000 CC (3 months) [® [® and Locator R-Tx® [Concerning CAS, friction involves only metal and polymer surfaces (titanium patrix/nylon or PEEK matrix). In vitro ,25 and cabutment , that reabutment ,13,21,276 years) , while a6 years) , and thi/1 year) . In gene months) . Neverth months) ,41. Concnths) [®  and at 1®. Also, its RD design present a vertical slit that expands during the IRC or CC, thus reducing the deterioration of the material. In addition, for Novaloc® and Locator R-Tx®, manufacturers provide color-RD associated with different levels of retention and wear behaviors. The variable selection of RD among studies can explain differences observed in wear and retentive properties.The remarkable mechanical properties of PEEK   could ex® RD. Only Cristache et al. [® loses more retention than BAS [® (including 50% in the first 3 months) and only 40% for the ball after 2 years [®, its retention force, after 1 to 2 years of wearing, remains higher [Comparative clinical ,6,7,15 ae et al.  found a e et al. ,32 agreethan BAS . This dethan BAS , and to than BAS  is mainlthan BAS . In one  2 years . Neverths higher  or simil®, which has higher initial retention, would lose its superiority over the ball after 300,000 CC (9 months), leading to a nonsignificant difference in the final retention between the two AS, after one year of clinical service . This difference might have a clinical relevance according to the initial retention needed and the interval between two maintenance sessions (activation or replacement of RD) [In conclusion, contact surfaces must be made in different materials  to limit wear and retention loss. Abi Nader et al.  estimatet of RD) . Both clt of RD) . The praThe previously analyzed in vitro studies only concerned parallel implants placed under optimal conditions. However, initial retention, loss of retention, wear, and postinsertion aftercare would occur much sooner in a clinical context. The prosthetic construction on the opposing arch , prosthetic hygiene, regular dental aftercare sessions and implant parameters  can easily be tuned in in vitro studies. Their impact on retention and wear of AS is presented in the following sections.According to the clinical context, when a 2-IRMO is indicated, the two implants should be placed (i) parallel to the vertical path of insertion and (ii) parallel to each other in the interforaminal region . However® manufacturer recommends using extended RD, which provide similar retentive behavior as standard RD used between 0 and 20 degrees. However, it is important to realize that using standard RD for huge interimplant angulations (60°) generate excessive initial retention force but rapid RD wear, due to the larger undercuts created by implant angulation [®, Locator®, Locator R-Tx® and Novaloc® [For interimplant angulation between 20 to 40 degrees, the Locatorgulation ,35,47,48Novaloc® ,35.Concerning BAS, until 30 degrees, implant angulation seems to have little impact on their initial retention and loss of retention ,19,27,49No studies were found on CAS regarding RD angulation, but clinical recommendations consist of aligning them with the insertion path.In IRMO, as implants are positioned in the interforaminal or intercanine area, the consensus establishes that the interimplant distance must range between 15 and 30 mm . AccordiSeveral experimental conditions can affect retention and wear observed in in vitro studies. Indeed, the use of a real denture or simulated denture blocks, the dry or wet environmental conditions, the dislodgement speed, the loading conditions, and the characteristics of the testing machine  could impact the obtained results.® after 6-month [Although mechanical stress is considered to be the main factor in wear and retention loss of AS, their varied and humid environments  have been studied and show little impact on AS retention and wear  22,26,4,50,51. T 6-month ,50 and a® does not depend on the rate up to 20 cycles/min but decreases significantly at higher speeds (40 cycles/min) [All studies summarized in les/min) .Some authors have observed variations in the retention force within a range of identical attachments , as well(i)prosthetic parameters ,(ii)in vitro experimental parameters ,(iii)clinical conditions in patient studies .This SR aims to compare the most common BAS and CAS used for 1 or 2-IRMO to assist the practitioner in making reasoned clinical choices. We consider that initial retention and prosthodontic maintenance related to wear and retention loss are critical parameters for the final decision. Thus, the PICO question comprises 5 different outcomes , all related but rarely evaluated in a single clinical or in vitro study. Both types of studies were included in this SR to explain the need for maintenance observed clinically by wear and retention loss mostly observed in vitro. Selected studies present substantial variability in their designs, with numerous parameters concerned:The heterogeneity of reported data also induces missing information in summary tables and limits the quality of evidence of this SR, direct comparison between results being difficult. No meta-analysis could be performed given the low confidence expected due to the lack of standardization of the selected studies.Additionally, the quality of clinical studies has been assessed as low using RoB 2 criteria, with 7/14 studies at high and 3/14 at moderate risk of bias. In particular, they present a high (4) or moderate (9) risk for other biases summarized in Finally, the studies selected could not fully address the SR question, but they highlighted trends supported by both in vitro and clinical studies. Every identified contradictory result was explained by further analysis of the study design and its bias. The following conclusion summarizes the significant findings, presents guidelines to improve in vitro studies on AS, and clinical recommendations for practitioners.® is now the most used. According to the objectives of this SR, three conclusions can emerge from the studies analyzed.Given the difference in the interlocking mechanisms, the variability of the studies procedures and the lack of standardized technical protocols, a direct comparison of the different AS remains impossible to determine the best AS in 1 or 2-IRMO. BAS remain the most evaluated AS in the literature due to their anteriority, whereas Locator® could become lower than the retention force of BAS, but the time threshold remains difficult to determine.First, the initial retention forces of CAS are higher than those of BAS, but their resistance to fatigue (retention stability) is much lower, related to the nylon RD wear. After a certain amount of IRC and/or CC, the retention force provided by the Locator®). In contrast, the metallic lamellae RD of BAS present relatively moderate wear at the base and discreet deformation at the top.Secondly, implant abutments in each system are barely affected by wear, unlike the RD that show significant plastic deformation, especially in the central core of CAS  or replacement (CAS), according to the AS. No significant difference was found in the overall maintenance incidence rate of each RD. Each practitioner will thus choose a system according to its patient needs and clinical situation. BAS initial retention is less effective but more durable than CAS, whereas CAS are more retentive but require a regular change of their RD to maintain their retention superiority.For in vitro studies, the following guidelines can be proposed to improve their repeatability and enable comparison between them. To characterize the retention of an AS in standard conditions, repeated measures on a single AS should be preferred. The tested AS must be identified: abutment, chosen retentive device, matrix housing. Blocks containing male and female parts should be carefully manufactured to ensure parallelism (or the required angulation) between the AS axes and the testing machine. Force measurements should be performed with an appropriate load cell (100–500 N), with a dislodging speed (50 mm/min), and in a solution  representative of the clinical use. Preliminary tests should be performed to set the pre-load value necessary to ensure complete interlocking of male and female parts before dislodgment, especially for polymeric RD. A relaxation time can be added for polymer RD presenting a viscoelastic behavior (Nylon) to let it recover its initial shape. Initial retention should be evaluated as the mean of the 10 first cycles. For fatigue testing, retention force should be reported at specified regular intervals  to reflect the progressive retention loss observed clinically.Based on this SR, clinical recommendations for AS in IRMO can be made:For all AS, practitioners can localize their implant according to the clinical situation but should avoid interimplant angulation, especially in the sagittal plane. They need to use dedicated instruments for the maintenance of the RD and favor polymeric RD (CAS) or precious alloy RD (BAS) versus titanium abutments to limit wear of the AS. Recommendations have to be explained to the patient concerning the cleansing and maintenance of prostheses, avoiding aggressive solutions.CAS should be preferred: (i) in situations of low vertical prosthetic space, although they have a larger cross-section compared to 2.25 mm standard diameter for BAS, (ii) when initial retention is required to be higher, , and (iii) if the axis of the implant is different from the insertion axis of the prosthesis over 30° with the use of extended RD adapted to high angulations. The standard 2.25 mm diameter BAS should be preferred: (i) in situations with low bone width and (ii) if the required retention is not strong but stable over time . They can be used until 30° angulation in accordance with the insertion pathway.These recommendations should be seen in the context of other essential aspects such as: (i) the implementation time, and the mastering of the system by the practitioner and the prosthetist, (ii) the easy placement and removal of the prosthesis by the patient, (iii) the inevitable frequent adjustments and repairs, and (iv) the patient compliance for recall.


Corn earworm and fall armyworm are the most important Lepidopteran pests in sweet corn worldwide. Timely application of insecticides during pollination is crucial to control both species and produce kernels with higher quality. Our results showed that applications of insecticides should be conducted at 48 h after pollination. Emamectin benzoate and chlorantraniliprole provided an adequate control of fall armyworm and corn earworm larvae. Furthermore, emamectin benzoate should be applied to larvae in later instars (fourth–sixth) while chlorantraniliprole and spinetoram should be sprayed when infestations of larvae in earlier instars (first–third) are observed.Helicoverpa zea (Boddie), and fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), in corn (Zea mays L.) at reproductive stages. Our objectives were to determine (1) the most appropriate time for insecticide applications and (2) the effect of four insecticides on the survival of larvae as well as their weight. ß-cyfluthrin (0.4 mL/L), chlorantraniliprole (0.6 mL/L), emamectin benzoate (0.2 g/L), and spinetoram (1.5 mL/L) were sprayed on silks of sweet corn planted in Isabela and Lajas, Puerto Rico 3 h before and 24 and 48 h after pollination. The number of kernels produced and the damage of larvae on kernels were quantified at harvest. In addition, percentages of mortality and changes on larval weight were noted at 96 h after insecticide applications. Insecticide sprays at 3 h before pollination reduced the number of kernels or were similar to the control in all treatments. However, emamectin benzoate sprayed in Lajas and chlorantraniliprole applied in Isabela at 48 h after pollination increased the number of kernels (281–294) and reduced the damage of larvae on kernels (<0.5%) compared to the control . Furthermore, applications of emamectin benzoate caused higher percentages of fall armyworm larval mortality (>70%). Conversely, ß-cyfluthrin and chlorantraniliprole caused lower percentages of mortality (<30%) and only chlorantraniliprole and spinetoram reduced the weight of corn earworm and fall armyworm larvae collected in both locations. This information may help pest management programs and corn breeders to schedule insecticide sprays and pollination in the field.Insecticide sprays are a common practice to control corn earworm,  Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae), and fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), are the most important pests affecting field/sweet corn (Zea mays L.) in the tropics, the United States, and worldwide [Corn earworm, orldwide ,3,4,5,6.orldwide  while coorldwide ,8,9. Bacillus thuringiensis, carbamates, and pyrethroids [Puerto Rico is an important winter nursery location mostly for field corn with more than 1000 ha planted in each season. In fact, private companies and universities from North America use Puerto Rico to advance generations, and for genetics and breeding studies . Furtherethroids ,13,14 weCarpophilus spp. (Coleoptera: Nitidulidae); and silk fly Euxesta spp. (Diptera: Ulidiidae)) in the kernels . Likewise, the efficacy of chlorantraniliprole, methoxyfenozide, and spinosyn to control corn earworm and fall armyworm larvae at reproductive stages by the reduction of the damage in the ears/kernels of sweet corn were reported in experimental trials in Florida and New York [Chemical control in combination with biological insecticides is the most common strategy to control Lepidopteran species in Puerto Rico ,11. In fNew York ,16,17. HThe intensive insecticide sprays  [® Prima® backpack . A total volume of 150 mL of insecticide solution was used per treatment at each time of pollination. The control was not sprayed. Sixty milligrams of fresh pollen (50–55% of moisture content) per silk was used for pollinations and tassel bags replaced the shoot bags when plants were pollinated. A randomized complete block design with three replications was used in each location, and ten cobs were used per each insecticide treatment and the control per replication (n = 120 per location). Cobs were harvested 21 days after the pollination. The number of kernels produced and the percentage of corn earworm and fall armyworm damage on the kernels under natural infestation were recorded. Experimental plots were 25 × 15 m in size. One sweet corn seed was planted every 0.30 m in each row (25 m length) and the separation between rows was 0.76 m. Each treatment was placed in every 4 rows. Plants with cobs at R1 stage, without visible silk hairs, were covered with shoot bags to avoid their exposure to the pollen. Then, 5 mL of each insecticide solution was sprayed at higher dosages  to four-n = 60 per location and species) in the laboratory at 18 to 20 °C, and a photoperiod of 12:12 h (L:D). The percentage of mortality and the weight of each larva were evaluated at 96 h after the insecticide application. Larvae were collected from leaves and ears of sweet corn ‘Suresweet 2011’ planted in Isabela and Lajas Research Substations at the University of Puerto Rico in June 2019 for corn earworm and June 2020 for fall armyworm. The weight of each larva was recorded, and then one fourth or fifth instar larva of corn earworm or fall armyworm was placed separately in a 20 mL plastic cup  containing soybean–wheat germ-based artificial diet . Fifteen larvae of each species per replication were treated topically with 3 mL (200 μL per larva) insecticide solution of ß-cyfluthrin, chlorantraniliprole, emamectin benzoate, and spinetoram per replication at the dosages described in A combined data analysis  was perfp ≤ 0.05) between the time of application were observed for all insecticides in the number of kernels produced  and fall armyworm  in Isabela and Lajas, respectively. In addition, significant differences were observed between larval weight and location x larval weight interaction for ß-cyfluthrin for corn earworm  to this insecticide. Spinetoram caused between 53 to 70% of larval mortality in Lajas and 30 to 36% in Isabela for both species. Conversely, applications of ß-cyfluthrin and chlorantraniliprole caused percentages of mortality below 27% in both populations . Corn eaOur data suggest that safe insecticide sprays on silks should be conducted at 48 h or longer after pollination. Applications of commercial dosages of ß-cyfluthrin and chlorantraniliprole at 3 h before pollination and 24 h after pollination reduced the number of kernels produced > 20% in Isabela. Likewise, applications of emamectin benzoate and spinetoram in Isabela and chlorantraniliprole and spinetoram in Lajas at 3 h before pollination reduced the seed yield from 23 to 60%. Apparently, the water or the insecticide solution applied on the silks may affect the pollen germination, female receptivity or the syngamy process which occurs in the next 28 h after pollination ,23. In fChlorantraniliprole was the most effective treatment in the field in Isabela at 48 after pollination. Likewise, spinetoram reduced the damage of Lepidopteran species on kernels at the same period although there were not statistical differences compared with the control. The direct application of both insecticides on the corn earworm and fall armyworm larvae caused lower percentages of mortality. However, there was a marked effect in the weight reduction in the larvae treated with these active ingredients. It has been reported that diamides cause an impaired regulation of muscle contraction  while spEmamectin benzoate sprayed at 48 after pollination was effective to control Lepidopteran species in Lajas where the rate of corn earworm and fall armyworm populations in cobs reached up to 1:1, as reported previously . In factIn summary, insecticides should be applied at least 48 h after pollination to control severe infestations of fall armyworm and corn earworm larvae on cobs/kernels of sweet corn. Emamectin benzoate provided an adequate control for both Lepidopteran species. If a second application is required or under infestations of earlier larvae instars (first–third), spinetoram or chlorantraniliprole could be used in rotation. Furthermore, the evaluation of synthetic insecticides in combination with biological control agents ,35 is ne


Procyanidin amendment did not affect the diversity and putative activity of microbial communities. In contrast, microbial interactions differed according to procyanidin amendment, with the results showing an enrichment of Entotheonellaeota and Mucoromycota in Serail soil and of Dependentiae and Rozellomycetes in Manziat soil.Some plant secondary metabolites, such as procyanidins, have been demonstrated to cause biological denitrification inhibition (BDI) of denitrifiers in soils concomitantly with a gain in plant biomass. The present work evaluated whether procyanidins had an impact on the diversity of nontarget microbial communities that are probably involved in soil fertility and ecosystem services. Lettuce plants were grown in two contrasting soils, namely Manziat (a loamy sand soil) and Serail (a sandy clay loam soil) with and without procyanidin amendment. Microbial diversity was assessed using Illumina sequencing of prokaryotic 16S rRNA gene and fungal ITS regions. We used a functional inference to evaluate the putative microbial functions present in both soils and reconstructed the microbial interaction network. The results showed a segregation of soil microbiomes present in Serail and Manziat that were dependent on specific soil edaphic variables. For example, Deltaproteobacteria was related to total nitrogen content in Manziat, while Leotiomycetes and Firmicutes were linked to Ca N2O is known to be a powerful greenhouse gas that is 1000 times less concentrated than CO2 but with up to 300 times greater global warming potential [Today, agriculture is facing a major challenge of feeding more and more people in shorter and shorter production times . This inotential . It contotential , with itotential . Moreoveotential ,20 can eotential ,22. In ootential ,24.2O emissions and nitrate leaching in the field across different zones and climates [One of the solutions would be to act on soil microorganisms related to the N cycle in order to limit the loss of N from agrosystems through the release of greenhouse gases or leaching. Several methods exist and have been tested, including the use of 3,4-dimethylpyrazole phosphate (DMPP) and dicyandiamide (DCD), which are molecules capable of blocking or delaying nitrification ,26. Thesclimates ,29,30. Hclimates .In addition to these chemical molecules acting on nitrification, it is also possible to act directly on the denitrification process. Indeed, it has been shown that some plants have the capacity to exude a flavonoid called procyanidins at the root level, which is able to inhibit soil denitrifying bacteria . This ph−1). The bacterial and fungal communities were monitored by Illumina sequencing using 16S rRNA gene and ITS regions, respectively. Functional inference of microbial abilities was predicted, and microbial networks were analyzed.In this study, we aimed to test the effect of procyanidin amendment on lettuce-associated microbiome cultivated in contrasting soils, namely a sandy clay loam soil texture from the Serail Experimental Station and a loamy sand texture from the agricultural field in Manziat. To achieve our purpose, the same variety of lettuce was planted during summer 2018 concomitantly in both Serail and Manziat that were amended or not with procyanidins at two concentrations  was grown in two experimental fields following a Fisher system [2) (planted soil with lettuce), with an unplanted area of 2 m × 1.4 m (2.8 m2) corresponding to unplanted soil (bulk soil). For planted soil amended with procyanidins, a concentration of about 210 kg ha−1 was used as the most effective concentration as determined in a previous study by Galland et al. (2019). Both sites were watered with 3 mm of water each day during the first week and with 8 mm of water per day for the next 10 days. Then, until the end of the experiment, 12 mm of water was applied on the fields every two days. Procyanidins were added 2 weeks after planting (stage with 7–9 leaves) to soil whose nitrate had been brought to the ZENIT grid, i.e., 40 kg NO3− ha−1 [®, Bordeaux, France) were applied in aqueous solution (standard water) by 2 nozzle spray booms to provide 500 L ha−1 or 0.42 L per plot between the lettuce rows, and the soil was then hoed. Each site was binned and watered (with 8 mm) just after the addition of procyanidins.Lettuce , which was collected and frozen in liquid NFor the soil analysis B, 3 trea® dsDNA Assay kit . Additionally, a DNA extraction was carried out without any biological matrix and considered as a negative control to evaluate ambient contaminations.Total DNA was extracted from 0.5 g of root-adhering soil (RAS) from 3 treatments (planted soil with and without procyanidin amendment and unplanted soil) in triplicates B using aTwo sets of primers were used to analyze either the prokaryotic or the fungal communities retrieved in lettuce.2, 0.8 μM of each primer, 0.2 mM of each dNTP, 8 μg of BSA (New England Biolabs), and 20 ng of genomic DNA in a final volume of 30 μL. All amplifications were carried out in triplicates on a Biorad C1000 thermal cycler (Biorad) using a PCR program composed of 10 min at 94 °C, 35 cycles of 1 min at 94 °C, 1 min at 58 °C, and 1 min 30 s at 72 °C, followed by 10 min at 72 °C.For prokaryotic community analyses, including both archaea and bacteria, amplification of the V3–V5 region of 16S rRNA genes was performed using the universal primers 515F (5′- α GTG-YCA-GCM-GCC-GCG-GTA -3′  and 909R2 (Invitrogen), 0.2 mM of each dNTP , 0.8 µM of each primer , 0.2 mg.mL−1 of bovine serum albumin , and 0.5 U of Taq DNA polymerase (Invitrogen). All amplifications were carried out on a Biorad C1000 thermal cycler  with one cycle of 3 min at 94 °C, followed by 35 cycles of 45 s at 94 °C, 45 s at 55 °C, 45 s at 72 °C, and a final extension step of 7 min at 72 °C.Regarding the fungal community analyses, the ITS-2 region was specifically amplified using the fITS7 (5′- α GTG ART CAT CGA ATC TTT G -3′) and ITS4 (5′- β TCC TCC GCT TAT TGA TAT GC -3′) primers ,43. Indehttp://www.biofidal-lab.com) (accessed on 27 June 2021).For both primer sets, α and β represent the two Illumina overhanging adapter sequences  allowing the construction of amplicon libraries by a two-step PCR. The three PCR replicates from each sample were pooled, purified with Agencourt AMPure XP PCR Purification kit , and quantified using the Quant-iT Picogreen dsDNA Assay kit . Sequencing on the Illumina MiSeq platform (2 × 300 bp paired-end reads) was performed by Biofidal  (accessed on 03 December 2020).For each dataset (prokaryotes and fungi), we tested the relative importance of different sources of variability  on the composition of microbial communities using nonparametric permutation-based multivariate analysis of variance  with abhttp://cran.r-project.org/web/packages/vegan/index.html) (accessed on 03 December 2020) in R software.To explain the prokaryotic and fungal community structure for different conditions in the present work, a canonical correspondence analysis (CCA) was performed linking community composition  and a combination of 9 environmental variables ). This analysis was performed with the vegan package  using a probabilistic model to assign multiple reference genomes in the SILVA database (v.123). For the subsequent transformation of SILVA-based genera to prokaryotic KEGG organisms, the latest available association matrix based on SILVA release 123 was used according to the programmer’s instructions. Taxonomic abundances were transformed to metabolic capabilities using the precomputed Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway reference profiles according to the MoP approach . A lineaThe tool FUNGuild was used to taxonomically parse fungal OTUs into several ecological categories   definingp value for each possible pairwise interaction to test the validity of the detected interaction, with the threshold set at 0.01. After applying the Benjamini–Hochberg correction for multiple tests, the corrected p values were converted to an adjacency matrix, from which the microbiome network was constructed. To detect hubs corresponding to nodes with a significantly larger number of connections, we calculated hub centrality scores. The centrality vectors were sorted to select the top 20 OTUs with the highest probability of being keystone species. To explore the global properties of networks, different metrics were estimated, including the number of nodes and edges, diameter, density and transitivity, and average path length. The graphical analysis was performed using the igraph R package.Microbiome networks were built as previously described  using a Differences in soil proprieties were found between both unplanted soils with more organic matter and organic carbon in Manziat soil compared to Serail soil. After lettuce growth, organic and carbon matter was enhanced in Serail soil, while it remain unchanged in Manziat soil. Procyanidin amendment had no impact on soil proprieties for Manziat soil but enhanced organic matter concentration in unplanted soil.To assess the influence of procyanidin amendment on soil microbiota, 16S and ITS metabarcoding was used to reveal the microbial community’s patterns. Rarefaction curves indicated that the sequencing effort was sufficient to describe fungal diversity, while in the prokaryotic dataset, some samples did not appear to have reached an asymptote . To gainTo evaluate the effects of lettuce seeding, procyanidin amendment, and/or soil type on the taxonomic composition of prokaryotic and fungal communities, we performed a permutational multivariate analysis of variance (PERMANOVA). This analysis was performed on two different levels of either OTU abundance  or OTU richness . The same trends were observed when considering the abundance and richness of OTUs . The soiWe investigated the impacts of the different treatments performed in the present work on the taxonomic composition of both prokaryote and fungal communities. Among the prokaryote dataset, the proportion of archaea over bacteria varied according to the soil considered, i.e., Manziat versus Serail A. ArchaeUsing discriminant analysis, we found clear differences in the most abundant fungal genera  between Manziat and Serail soil B. Some gTo evaluate the existence of common, shared, and specific OTUs among treatments, the distributions of OTUs were analyzed . For proFor fungi B, in Man2+ for the unamended lettuce (L0S). In Manziat, it was mostly related to C/N ratio, Ntot, OM, and OC for the amended lettuce (LPM) and to sand for the unamended lettuce (L0M). Among prokaryotic and fungal communities, Sordariomycetes and Firmicutes were mainly related to CEC and/or Ca2+, while Dothideomycetes were related to silt as were Actinobacteria, Planctomycetes, and Leotiomycetes  and nrfA (nitrite reductase), while two in Serail were related to the N cycle, namely narG/narZ (nitrate reductase) and nxrA (nitrate oxidoreductase). In Serail, it should be noted that three categories were related to the biosynthesis of siderophores and nonribosomal peptides and two categories were related to multidrug efflux pump, which were absent in Manziat soil. In contrast, interestingly, procyanidin treatment did not influence the statistically inferred functions.Unsurprisingly, among the 3551 KEGG categories inferred from the prokaryotic dataset, numerous categories were different between soils (Manziat versus Serail). Specifically, 56 categories were statistically enriched in Manziat soil, while 55 categories were enriched in Serail soil based on an LDA score >2 . Among tAmong the 427 fungal OTUs, only 280 were functionally inferred  and 227 were retained because they fitted both criteria for an acceptable confidence rank and a blast identity >95%. According to trophic modes, saprotrophs were dominant irrespective of the samples . Other tWe used a network inference based on strong and significant correlations to explore the co-occurrences among bacterial and fungal phyla colonizing the RAS of lettuce plants, amended and unamended with procyanidins, grown in Serail and Manziat soils . In the Network complexity, indicated by the number and density of edges, was different between the two soils planted with lettuce . The netThe microbial network also differed for the two amended and unamended soils with regard to composition. The RAS network of the unamended Serail soil was more enriched in Euryarchaeota, Spirochaetes, Basidiomycetes, and Glomeromycota, while the network of the amended soil was enriched in Entotheonellaeota and Mucoromycota. The RAS network of the unamended Manziat soil had lower proportions of Basidiomycetes and Latescibacteria, while it was enriched in Dependentiae, Aramatomonadetes, and Rozellomycetes compared to the amended Manziat soil. The RAS network of the amended Manziat soil was also enriched with Mucoromycota as observed for the amended Serail soil. Notably, Serail soil networks (unamended and unamended) were more diversified in gungi than Manziat soil.The soil environment maintains a high microbial diversity harboring different functions and providing ecosystem services, such as plant growth stimulation and health protection. Manziat and Serail soils harbor a rich microbial community that is clearly distinguishable from each other in its diversity and functions.2+. The effect of Ca2+ on microbial communities has been documented in a few studies. Ca2+ in soil influences many soil factors, including pH [2+ could accompany a change in other soil parameters, thereby resulting in variations in microbial diversity between calcium-amended and reference watershed soils [The presence of certain phyla has been correlated with certain edaphic variables as demonstrated by Zheng et al. (2019), suggesting that edaphic factors participate in shaping microbial community composition and diversity . Indeed,uding pH . Indeed,ed soils .2O emissions from agricultural soils [−1 inhibited denitrification activity and acted on the abundance of denitrifying bacterial communities in both soils. Indeed, whether in loamy sand or sandy clay loam soil, denitrifying communities were less abundant in procyanidin-amended soil than in unamended soil [2O emissions in agricultural soils, this molecule should not have any impact on soil fertility and consequently on the diversity and functioning of nontarget soil microbial communities. For example, Kong et al. (2016) demonstrated that soil amended with DMPP at doses consistent with, and 10-fold higher than, those recommended did not exert significant negative impacts on nontarget soil functions or microbial community size or composition after short-term exposure [−1 corresponds to a dose with a significant and specific impact on denitrification activity compared to the lower doses  tested in Galland et al. [−1 would be more bioavailable in the soil than less concentrated procyanidins and hence in better contact with microorganisms. The fact that procyanidin amendment at 210 kg ha−1 did not affect microbial diversity ensures the environmental safety of procyanidin intervention in soils under field conditions.In this study, we used procyanidins as denitrification inhibitors. Extensive experimental evidence has demonstrated the effectiveness of these specific compounds in (i) reducing N losses by denitrification and hence increasing the nitrate pool in the soil, which can then be used for plant growth, and (ii) decreasing Nal soils ,35,36,71al soils . No effeded soil . Howeverexposure . In thisUnder natural conditions, Manziat soil exhibited a more complex and stable network comprising more interacting species than Serail soil. Procyanidin amendment decreased the order organization of Manziat soil, while it enhanced that of Serail soil. Interestingly, procyanidin amendment improved lettuce growth in both soils , suggest2O emissions in agricultural soils, this molecule should not have any impact on soil fertility and consequently the diversity and functioning of nontarget soil microbial communities. In this study, we demonstrated that procyanidin amendment to lettuce plants had no impact on soil microbial diversity. Indeed, bacterial and fungal diversity did not change with procyanidin amendment and only changed according to soil type and edaphic variables. Therefore, procyanidins may represent an alternative to the use of N fertilizers, thus reducing N input and N2O emissions.In order to use procyanidins as a sustainable solution to reduce N input and N


Early recurrence of oesophageal squamous cell carcinoma (SCC) is defined as recurrence after surgery within 1 year, and appears as local recurrence, distant recurrence, and lymph node positive and disseminated recurrence. Contrast-enhanced computed tomography (CECT) is recommended for diagnosis of primary tumor and initial staging of oesophageal SCC, but it cannot be used to predict early recurrence. It is reported that radiomics can help predict preoperative stages of oesophageal SCC, lymph node metastasis before operation, and 3-year overall survival of oesophageal SCC patients following chemoradiotherapy by extracting high-throughput quantitative features from CT images. This study aimed to develop models based on CT radiomics and clinical features of oesophageal SCC to predict early recurrence of locally advanced cancer.We collected electronic medical records and image data of 197 patients with confirmed locally advanced oesophageal SCC. These patients were randomly allocated to 137 patients in the training cohort and 60 in the test cohort. 352 radiomics features were extracted by delineating region-of-interest (ROI) around the lesion on CECT images and clinical signature was generated by medical records. The radiomics model, clinical model, the combined model of radiomics and clinical features were developed by radiomics features and/or clinical characteristics. Predicting performance of the three models was assessed with area under receiver operating characteristic curve (AUC), accuracy and F-1 score.Eleven radiomics features and/or six clinical signatures were selected to build prediction models related to recurrence of locally advanced oesophageal SCC after trimodal therapy. The AUC of integration of radiomics and clinical models was better than that of radiomics or clinical model for the training cohort  and for the validation cohort . Integrated model of radiomics and clinical features showed good performance in predicting early recurrence of locally advanced oesophageal SCC for both the training and validation cohorts .The integrated model of CECT radiomics and clinical features may be a potential imaging biomarker to predict early recurrence of locally advanced oesophageal SCC after trimodal therapy. Oesophageal cancer is the eighth most common malignancies in the world , and squ18 F-fluorodeoxyglucose-positron emission tomography CT (FDG-PET CT) is mainly used for judging M stage [Currently, contrast-enhanced computed tomography (CECT) is commonly used for initial judging T and N staging of primary tumor , and 18  M stage , but the M stage , 16. It  M stage , lymph n M stage . Althoug M stage , there iEthical approval to perform this retrospective research was obtained from institution ethics committee of our hospital, and informed consent was waived. We retrospectively collected CT data and medical records of patients with locally advanced oesophageal SCC at our hospital from March 2016 to August 2018.n = 26); or (2) with incomplete clinicopathological information (n = 7). Consequently, 197 patients were enrolled into this study in total. According to the published report by Chen et al. [The enrolled patients needed to meet the following inclusion criteria: 1) oesophageal SCC patients underwent CECT and images with good quality were obtained within 2 weeks before the surgery; (2) the patients did not receive any tumor-related treatments  before undergoing the CT scans; (3) patients were confirmed no distant metastasis (M1) before surgery based on CT and/or PET-CT scans; (4) patients received standardized trimodal therapy, and were confirmed locally advanced oesophageal SCC and no residual tumor (R0) by postoperative pathology; and (5) patients were followed up for at least 1 year after trimodal therapy according to the latest edition of National Comprehensive Cancer Network (NCCN) guidelines  In our sn et al. , all par oesophagArchived clinical data, such as gender, age, histological grade, pT staging, pN staging and comprehensive staging were extracted by reviewing the medical records. Tumor staging was judged by the American Joint Committee on Cancer TNM Staging System Manual, 8th Edition .18FDG-PET CT for the confirmation of recurrence [According to the latest edition of the NCCN guidelines , asymptocurrence . In our currence –9.All patients we collected underwent CECT scans with 128 multi-detector scanners . Patients who were suspected of having oesophageal cancer were required to drink 100–200 ml water before CT, which was used as oesophageal negative contrast material. During the CT examination, the patients were scanned in the supine position and hold a breath for 10–15 s to get satisfactory images. Following routine non-enhanced CT, CECT was performed a 25–30 s delay after intravenous injection of 1.5 mL/kg contrast material  at the rate of 3.0 mL/s with a pump injector . The parameters for the CT scans were given as follows: 120 kV, 200 mAs, 0.5 s rotation time, detector collimation of 64 × 0.6 mm, pitch of 0.9, slice thickness of 5.0 mm, and matrix of 512 × 512 mm. The coverage of CT examination was from the base of skull to the middle of the left kidney. All CECT image data that were used for extracting features were obtained by picture archiving and communication system.http://bit.ly/IBEX_MDAnderson), an open source software, which ran on 64-bit MATLAB 2013Ra [The manual segmentation of tumor images Fig.  was perfB 2013Ra . During B 2013Ra , 28. WheIn order to guarantee the reproducibility of results, we randomly selected consecutive 50 cases’ CECT data from all patients for intra- and inter-observer consistency testing. The intra-class correlation coefficient (ICC) was an evaluation index to assess intra- and inter-observer agreements. It meant good consistency when the ICC score was greater than 0.75. The ICC of intra-observer was measured by reader 1 drawing the outline of ROI twice within one week following the same steps according to the published report by Chen et al. . In addiIn order to avoid the curse of dimensionality and reduce the bias from radiomics features during modeling , we adopnorm = First, all the radiomics features extracted from imaging data were processed to z-score normalization (mean is zero and variance is one) : x norm t test or the Mann-Whitney U test was further used to select potential important features of training cohort. The radiomics features without statistical significance  were excluded.Second, the independent samples Finally, the least absolute shrinkage and selection operator method (LASSO) , capableThe optimal selected radiomics features and clinical characteristics were used to construct three predictive models through logistic regression, which was a classical machine learning method. The three predictive models were a radiomics model, a clinical model, and an integration of the radiomics and clinical features. The adjustment of the optimal predictive model followed the same process as described above. The confusion matrix calculated the area under receiver operating characteristic curve (AUC), accuracy, F-1score as well as sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) to evaluate training results and test results of the three predictive models.https://www.r-project.org/). The “glmnet” package was used to perform LASSO regression, and “pROC” package was used to draw receiver operating characteristic (ROC) curves. Statistical analysis methods varied with the type of clinical characteristics. The normality of distribution was evaluated by Shapiro-Wilk test and the homogeneity of variance was tested by Bartlett test. Continuous variables, expressed as the mean or median, were compared by the independent t-test. The categorical variables were described in percentiles and compared using the Chi-square test or Fisher’s exact test. P < 0.05 meant statistical difference.All data of radiomics characteristics were conducted through R  whereas age and gender were not statistically significant . All clinical features were used to establish a clinical model.In our cohort of 197 patients with locally advanced oesophageal SCC, 101 patients recurred whereas the remaining 96 did not. In the 101 patients with recurred oesophageal SCC, the recurrence time was more than 3 months and less than or equal to 6 months after the treatments in 27 patients, more than 6 months and less than or equal to 9 months after the treatments in 39 patients, and more than 9 months and less than or equal to 12 months after the treatments in 35 patients. The clinical characteristics of locally advanced oesophageal SCC in the early recurrence and non–early recurrence dataset are recorded in Table For intra-observer agreement of CT radiomics feature extraction, there were 275 extracted features with ICC greater than 0.75 whereas ICC was not greater than 0.75 for 77 features Fig. a. In tert test or Mann-Whitney U test showed that out of 263 features, 249 features were significantly different . Therefore, 249 features in total were used for LASSO regression, and 11 features were selected by LASSO (22.6:1 ratio)  whereas there were no statistical difference between the radiomics model and the clinical model .Through logistic regression, the 11 selected optimal radiomics features and six clinical features were applied to establish three prediction models in predicting early recurrence of locally advanced oesophageal SCC including a radiomics model, a clinical model, and a model that integrated radiomics and clinical characteristics. The most suitable model was selected by AUC, accuracy, and F-1 score together with sensitivity, specificity, PPV, NPV as shown in Table Radiomics is a nascent image analysis method by extracting a large number of quantitative features to quantify tumor heterogeneity based on imaging data, which is of great significance for personalized oncology –33. RadiOur study shows that pT stage, pN stage, pTNM stage and differentiation degree are independent clinical risk factors of early recurrence in locally advanced oesophageal SCC patients whereas age and gender are not among the six clinical characteristics which are used to establish the clinical model. As reported, the pT stage, pN stage and pTNM stage may be related to invasive depth of the tumor itself and the extent of lymphatic vessel invasion , 35. As As shown in this paper, we selected 11 most unique features from all 352 features to build the CT radiomics model. The 11 features include texture features, intensity histogram features and shape features, which could be useful for assessing early recurrence of locally advanced oesophageal SCC. The six texture features and one intensity histogram feature include X45.7 Difference Entropy, X135.7 Dissimilarity, X0.1 Information Measure Corr1, X90.7 Information Measure Corr2, X45.7 Inverse Variance, X90 High Gray Level Run Empha, and Kurtosis. They can mainly represent the texture characteristics of tumors, which are highly associated with the heterogeneity and prognosis of the tumour , 38. ShaThe combined model obtains more satisfactory predictive results  compared with the other two models. It can be explained by the fact that the clinical and radiomics features complement each other to improve the predictive power of the combined model , 39, 40.According to relevant literature , 41, 42,There are still some limitations in our retrospective study. First of all, this study is a relatively small sample and single-center study, and the applicability and universality of our findings needs to be further verified. Despite this limitation, our sample size was larger than that in the published reports focusing on radiomics study of oesophageal cancer , 45, sugOur study explored the radiomics approach based on CECT images as a feasible method to predict early recurrence of locally advanced oesophageal SCC after trimodal therapy. The model by integrating CECT radiomics and clinical features can further improve the predictive performance of early recurrence of locally advanced oesophageal SCC when compared to the radiomics model or clinical model. We hope that our integrated model can be helpful for selecting the patients with high risk of early recurrence as early as possible to undergo effective personalized treatment and closer follow-up to prevent early recurrence of this cancer.