Feasibility and Colonoscopy Yield Using the Fecal Immunochemical Test (FIT)-Based Colorectal Cancer Screening in a Latin America Country.

BACKGROUND & AIMS: Organized colorectal cancer (CRC) screening is not widely practiced in Latin America and the results of regional studies may help overcome barriers for implementation of national screening programs. We aimed to describe the implementation and findings of a fecal immunochemical test (FIT)-based program in Brazil. METHODS: In a prospective population-based study, asymptomatic individuals (50-75 years old) from Sao Paulo city were invited to undergo FIT for CRC screening. Participants with positive FIT (≥10 µg Hb/g feces) were referred for colonoscopy. Subjects were classified into groups according to the presence of CRC, precursor lesions, and other benign findings, possibly related to bleeding. RESULTS: Of a total of 9881 subjects, 7.8% had positive FIT and colonoscopy compliance was 68.9% (n = 535). Boston scale was considered adequate in 99% and cecal intubation rate was 99.4%. CRC was diagnosed in 5.9% of the cases, adenoma in 63.2%, advanced adenoma in 31.4%, and advanced neoplasia in 33.0%. Age was positively associated with CRC (P = .03). Higher FIT concentrations were associated with increased detection of CRC (P < .008), advanced adenoma (P < .001), and advanced neoplasia (P < .001). CONCLUSIONS: Implementation of a FIT-based CRC screening program was feasible in a low-resource setting, and there was a high yield for neoplasia in individuals with a positive FIT. This approach could be used as a model to plan and disseminate organized CRC screening more broadly in Brazil and Latin America.

Persistent vaginal bleeding during gender-affirming hormone therapy in transgender men.

PURPOSE: While it is common for menstrual cycles to cease within the initial 6 months of treatment, there are instances where some transgender men may not experience this cessation. We analyzed transgender men undergoing gender-affirming hormone therapy (GAHT) with testosterone who experienced breakthrough bleeding in order to identify the factors associated with this condition. METHODS: In this case-control study, 24 transgender men in the case group and 48 in the control group were assessed for clinical, sociodemographic, hormonal, and body composition variables using dual-energy X-ray absorptiometry. All participants had been on GATH for at least 6 months. RESULTS: A few transgender men experienced persistent breakthrough bleeding, which was associated with decreased testosterone levels and free androgen index (FAI) compared with controls (p = 0.002 and p = 0.008, respectively). Among individuals with breakthrough bleeding, 50% had testosterone levels below the lowest tertile calculated for the sample, compared with 18.8% on controls (p = 0.007). After therapy adjustment, testosterone levels increased compared with the values obtained in the initial bleeding episode (p = 0.031). Eight transgender men required the addition of an oral progestogen to achieve amenorrhea, and these individuals had higher BMI than those in whom the adjustment of the parenteral testosterone dose was adequate (p = 0.026). A univariate prevalence ratio analysis revealed a negative association of persistent bleeding with testosterone levels (p = 0.028) and FAI levels (p = 0.019). CONCLUSION: Higher BMI and lower levels of testosterone and FAI were the main factors associated with breakthrough bleeding in transgender men.

A new 3D model of L929 fibroblasts microtissues uncovers the effects of Bothrops erythromelas venom and its antivenom.

In Brazil, around 80% of snakebites are caused by snakes of the genus Bothrops. A three-dimensional culture model was standardized and used to perform treatments with Bothrops erythromelas venom (BeV) and its antivenom (AV). The MRC-5 and L929 cell lines were cultured at increasing cell densities. Morphometric parameters were evaluated through images obtained from an inverted microscope: solidity, circularity, and Feret diameter. L929 microtissues (MT) showed better morphometric data, and thus they were used for further analysis. MT viability was assessed using the acridine orange and ethidium bromide staining method, which showed viable cells in the MT on days 5, 7, and 10 of cultivation. Histochemical and histological analyses were performed, including hematoxylin/eosin staining, which showed a good structure of the spheroids. Alcian blue staining revealed the presence of acid proteoglycans. Immunohistochemical analysis with ki-67 showed different patterns of cell proliferation. The MT were also subjected to pharmacological tests using the BeV, in the presence or absence of its AV. The results showed that the venom was not cytotoxic, but it caused morphological changes. The MT showed cell detachment, losing their structure. The antivenom was able to partially prevent the venom activities.

Probiotic Potential and Application of Indigenous Non-Starter Lactic Acid Bacteria in Ripened Short-Aged Cheese.

There are massive sources of lactic acid bacteria (LAB) in traditional dairy products. Some of these indigenous strains could be novel probiotics with applications in human health and supply the growing needs of the probiotic industry. In this work, were analyzed the probiotic and technological properties of three Lactobacilli strains isolated from traditional Brazilian cheeses. In vitro tests showed that the three strains are safe and have probiotic features. They presented antimicrobial activity against pathogenic bacteria, auto-aggregation values around 60%, high biofilm formation properties, and a survivor of more than 65% to simulated acid conditions and more than 100% to bile salts. The three strains were used as adjunct cultures separately in a pilot-scale production of Prato cheese. After 45 days of ripening, the lactobacilli counts in the cheeses were close to 8 Log CFU/g, and was observed a reduction in the lactococci counts (around -3 Log CFU/g) in a strain-dependent manner. Cheese primary and secondary proteolysis were unaffected by the probiotic candidates during the ripening, and the strains showed no lipolytic effect, as no changes in the fatty acid profile of cheeses were observed. Thus, our findings suggest that the three strains evaluated have probiotic properties and have potential as adjunct non-starter lactic acid bacteria (NSLAB) to improve the quality and functionality of short-aged cheeses.

Brazilian indigenous nonstarter lactic acid bacteria enhance the diversification of volatile compounds in short-aged cheese.

There is growing interest in using autochthonous lactic acid bacteria (LAB) that provide unique sensory characteristics to dairy products without affecting their safety and quality. This work studied the capacity of three Brazilian indigenous nonstarter LABs (NSLAB) to produce biogenic amines (BAs) and evaluated their effect on the volatile organic compounds (VOCs), microbial LAB communities, and physicochemical profile of short-aged cheese. Initially, the strain's potential for biosynthesis of BAs was assessed by PCR and in vitro assays. Then, a pilot-scale cheese was produced, including the NSLAB, and the microbial and VOC profiles were analyzed after 25 and 45 days of ripening. As a results, the strains did not present genes related to relevant BAs and did not produce them in vitro. During cheese ripening, the Lactococci counts were reduced, probably in the production of alcohols and acid compounds by the NSLAB. Each strain produces a unique VOC profile that changes over the ripening time without the main VOCs related to rancid or old cheese. Particularly, the use of the strain Lacticaseibacillus. paracasei ItalPN16 resulted in production of ester compounds with fruity notes. Thus, indigenous NSLAB could be a valuable tool for the enhancement and diversification of flavor in short-aged cheese.

Homologous equivalence study of immunogenicity after third dose of Covid-19 vaccine (recombinant) with an interval of six months after the second dose, comparing the interval of eight and 12 weeks between the first two doses.

BACKGROUND: In response to the coronavirus disease 2019 (Covid-19) pandemic, Brazil authorised the Astra Zeneca/Fiocruz vaccine in January 2021. As the Delta variant emerged in May 2021, interval between vaccine doses was adjusted. By September 2021, the Brazilian National Immunisation Program recommended a booster dose for individuals over 70, and later expanded the recommendation to all adults. OBJECTIVES: Assess the equivalence of IgG antibody response against the Covid-19 S protein before and approximately 28 days after the third dose of a Covid-19 recombinant vaccine. Two groups received initial two doses with intervals of eight and 12 weeks. METHODS: This is a phase IV clinical study, uncontrolled, non-randomised. The study proposes calculating the ratio of geometric means titres (GMT) 28 days after the third dose, with a target ratio of confidence interval (CI) between 0.77 and 1.3. FINDINGS: In the primary endpoint, there was no equivalence between the eight- and 12-week intervals with a slight variation favouring the eight-week group. Post-third dose, both groups showed increases titres at 28 days, three months, six months and 12 months. Both groups responded similarly to Delta and Omicron BA.1, with a more significant increase for Delta. MAIN CONCLUSIONS: The study showed strong and consistent immune response in all age groups receiving the Covid-19 recombinant vaccine. Third dose elicited an increase in GMT by at least three times aligned with Ministry of Health strategies emphasising Bio-Manguinhos crucial role in pandemic control in the country.

Toxigenic characterization, spoilage potential, and antimicrobial susceptibility of coagulase-positive Staphylococcus species isolated from Minas Frescal cheese.

This study aimed to identify coagulase-positive staphylococci (CPS) species from 21 samples of clandestine Minas Frescal cheese, investigate the potential for deterioration in psychrotrophic and mesophilic conditions, verify the toxigenic potential of Staphylococcus aureus, and determine the antimicrobial susceptibility profile of toxigenic S. aureus. Species determination was performed based on the detection of ß-hemolysis in 5% ovine blood agar; fermentation of mannitol, maltose, and trehalose sugars; and production of acetoin. After species determination, DNA extraction and analysis was performed for S. aureus colonies for genes encoding staphylococcal toxins (eta, etb, tst, sea, seb, sec, sed, and see) using 2 multiplex PCR assays. Isolates identified as toxigenic S. aureus were tested for antimicrobial susceptibility to tetracycline, erythromycin, clindamycin, gentamicin, ciprofloxacin, sulfazotrim, trimethoprim, streptomycin, cefoxitin, vancomycin and enrofloxacin. Elevated CPS counts were observed with an average of >6 log cfu/g. Of the 355 isolates, 177 (49.86%) were identified as S. aureus. Staphylococcus hyicus, Staphylococcus intermedius, Staphylococcus delphini, and Staphylococcus coagulans were identified in 3 (0.84%), 2 (0.56%), 2 (0.56%), and 1 (0.28%) isolates, respectively. Of the total number of S. aureus, 25 (52.08%) were positive for the gene that encodes for toxic shock toxin (TSST-1). Another 16 (33.33%) were positive for the sea gene, and 4 isolates (8.33%) were positive for see and one isolate each was positive for seb (2.08%), sec (2.08%), and etb (2.08%) genes. All isolates demonstrated lipolytic activity under mesophilic and psychrotrophic conditions. S. intermedius and S. hyicus had the most prominent proteolytic potential. Multidrug resistance was observed in most of the potentially toxigenic isolates, with clindamycin having the lowest efficiency (40%), whereas the aminoglycosides (gentamicin and streptomycin) had the highest effectiveness demonstrating inhibition in all evaluated isolates. Methicillin-resistant S. aureus (MRSA) was detected. Minas Frescal cheeses, marketed in the north of Tocantins in the Brazilian Amazon region, do not comply with legal quality standards and pose a public health risk due to the enterotoxigenic potential of multiresistant isolates, in addition to low shelf life of the samples given the high spoilage potential of this microbiota.

Monitoring financial healthcare protection in Brazil: evolution, inequalities, and associated factors.

OBJECTIVES: Although catastrophic health spending is the main measure for assessing financial healthcare protection, it varies considerably in methodological and empirical terms, which hinders comparison between studies. The aim of this study was to measure the prevalence of catastrophic health spending in Brazil in 2003, 2009, and 2018, its associated factors, and disparities in prevalence distribution according to socioeconomic status. STUDY DESIGN: This was a time series study. METHODS: Data from the Household Budget Surveys were used. Prevalence of catastrophic health spending was measured as a percentage of the budget and ability to pay, considering thresholds of 10, 25, and 40%. It was determined whether household, family, and household head characteristics influence the likelihood of incurring catastrophic health spending. Households were stratified by income deciles, consumption, and wealth score. RESULTS: There was an increase in prevalence of catastrophic health spending between 2003 and 2009 in Brazil and a slight reduction in 2018. The wealth score showed more pronounced distributional effects between the poor and the rich, with the former being the most affected by catastrophic health spending. Consumption showed greater percentage variations in the prevalence of catastrophic health spending. The prevalence of catastrophic health spending was positively associated with the presence of older adults, age and female household head, rural area, receipt of government benefits, and some degree of food insecurity. CONCLUSIONS: The poorest families are most affected by catastrophic health spending in Brazil, requiring more effective and equitable policies to mitigate financial risk.

In-hospital breastfeeding and predictive factors during the SARS-CoV-2 pandemic: A retrospective cohort study - Aleitamento materno hospitalar e fatores preditores durante a pandemia pelo SARS-CoV-2: Coorte retrospectiva.

PURPOSE: To analyze breastfeeding and the factors that positively influence the first hour of life, during hospitalization, and at discharge during the SARS-CoV-2 pandemic. DESIGN AND METHOD: This is a retrospective cohort study, with data collected from medical records. Consisting of 225 mother-newborn dyads with deliveries between 2020 and 2021. Breastfeeding in the first hour of life, during hospitalization, and at discharge was considered as the outcome variable. The independent variables were sociodemographic, obstetric, and neonatal data. The analysis was performed with bivariate and multivariate regression through a generalized linear model (Poisson family), with a 5% significance level. It was approved by the Institutional Review Board (IRB), under approval number 4,911,317. RESULT: Newborns of women without COVID-19 suspicion or diagnosis and who had skin-to-skin contact with their mother at birth are twice as likely to be breastfed in the first hour of life. Absence of complications in the newborn during hospitalization and no COVID-19 suspicion or diagnosis double the exclusive breastfeeding rate during hospitalization. Newborns exclusively breastfed during hospitalization present 1.6 times more chances of being exclusively breastfeeding at hospital discharge. CONCLUSION: It was evidence that women who gave birth without COVID-19 suspicion, and newborns who had skin-to-skin contact with their mother at birth represented a predictive factor for favoring exclusive breastfeeding. PRACTICE IMPLICATIONS: This research contributes to the innovation of evaluating breastfeeding in the newborn's first hour of life, during hospitalization, and at discharge in a pandemic context.

Potential Involvement of the South American Lungfish Intelectin-2 in Innate-Associated Immune Modulation.

Intelectins belong to a family of lectins with specific and transitory carbohydrate interaction capabilities. These interactions are related to the activity of agglutinating pathogens, as intelectins play a significant role in immunity. Despite the prominent immune defense function of intelectins, limited information about its structural characteristics and carbohydrate interaction properties is available. This study investigated an intelectin transcript identified in RNA-seq data obtained from the South American lungfish (Lepidosiren paradoxa), namely LpITLN2-B. The structural analyses predicted LpITLN2-B to be a homo-trimeric globular protein with the fibrinogen-like functional domain (FReD), exhibiting a molecular mass of 57 kDa. The quaternary structure is subdivided into three monomers, A, B, and C, and each domain comprises 11 ß-sheets: an anti-parallel ß-sheet, a ß-hairpin, and a disordered ß-sheet structure. Molecular docking demonstrates a significant interaction with disaccharides rather than monosaccharides. The preferential interaction with disaccharides highlights the potential interaction with pathogen molecules, such as LPS and Poly(I:C). The hemagglutination assay inhibited lectins activity, especially maltose and sucrose, highlighting lectin activity in L. paradoxa samples. Overall, our results show the potential relevance of LpITLN2-B in L. paradoxa immune defense against pathogens.

Vaccine adherence and adverse events of the SARS-COV vaccine in patients with inflammatory bowel disease.

OBJECTIVE: To assess adherence to and the adverse effects of the SARS-COV vaccine in patients with inflammatory bowel disease (IBD). PATIENTS AND METHODS: This is an observational, analytical, cross-sectional study. Sociodemographic and clinical data, SARS-COV vaccine data, medications for IBD with use during the vaccination period, and adverse events during the vaccination period were collected. Carried out logistic regressions with robust variance estimation to estimate the odds ratio with the respective 95% confidence intervals (95%CI) to assess the factors associated with non-serious adverse effects following vaccine doses as outcome variables. RESULTS: 194 patients participated, with vaccine compliance of 78.3% for three doses of any vaccine (n=152). Local symptoms and mild systemic symptoms predominated, regardless of the type of vaccine. The first dose of the SARS-COV vaccine with AstraZeneca had a higher percentage of patients with vaccine symptoms. AstraZeneca vaccine increased the chance of non-serious adverse effects in IBD patients by 2.65 times (95% CI: 1.38-5.08; p=0.003), regardless of age, gender, physical activity, excess weight, use of disease-modifying drugs, immunobiological and corticosteroids. CoronaVac vaccine was associated with asymptomatic patients at the first dose and reduced the chance of adverse effects by 0.28 times (OR: 0.284; 95%CI: 0.13-0.62; p=0.002). CONCLUSION: Local symptoms and mild systemic symptoms predominated, regardless of the type of vaccine. Using CoronaVac in the first dose reduced the chances of adverse effects, while AstraZeneca increased the risk of adverse effects.

Contamination risk by heavy metals and enzymatic stoichiometry in agricultural soils under intense use of pesticides.

Soil contamination by heavy metals (HM) from pesticides poses a serious environmental threat, affecting sustainability and agricultural productivity. Soil enzymes are essential for biochemical reactions such as organic matter decomposition and nutrient cycling and are vital for maintaining soil health. However, the effects of HM on soil enzyme activity are not yet well understood. This study examined the impact of HM contamination on enzymatic stoichiometry in regions with intensive pesticide use. We selected flower cultivation areas with 5 years (CA1) and 10 years (CA2) of pesticide exposure and a native forest area (NFA) as a reference during the dry and rainy seasons. We measured Cd, Cu, Mn, Pb, and Zn levels and employed ecological risk indices to assess contamination levels. We also analyzed enzyme activities (arylsulfatase, ß-glucosidase, acid phosphatase, urease) and enzymatic stoichiometry. CA2 exhibited the highest concentrations of Cd, Cu, and Mn in both periods, while Zn was highest in both CA1 and CA2. CA2 had higher values for all indices, indicating significant contamination. Compared with NFA, arylsulfatase activity was lower in cultivated areas during both periods, suggesting decreased soil quality. We found negative correlations between Cu, Mn, Zn, and arylsulfatase, as well as a reduction in urease with Cd; these elements also increased microbial C limitation. Our findings show that continuous pesticide input increases HM levels and that enzyme activity and stoichiometry are effective bioindicator of soil contamination. This study underscores the urgent need for guidelines to protect soils from prolonged HM buildup.

HPV-related oropharyngeal carcinoma remains infrequent over 25 years in a Brazilian Oral Pathology Center: A cross-sectional study with literature review.

BACKGROUND: The aim was to evaluate the frequency, clinicopathological features, and HPV status of oropharyngeal squamous cell carcinoma (OP-SCC) and benign HPV-related epithelial lesions of the oropharynx over the last 25 years. Moreover, a literature review was performed to investigate HPV frequency in OP-SCC samples diagnosed in Brazilian Centers. MATERIAL AND METHODS: A cross-sectional study analyzed OP-SCC, squamous papilloma, verruca vulgaris, and condyloma accuminatum, diagnosed from 1997 to 2021. HPV status of OP-SCC was determined by immunohistochemistry and "in situ" hybridization. Bivariate statistics were performed (p≤0.05). For the literature review, MEDLINE/PubMed, Web of Science, EMBASE, and Scopus were searched. Two independent reviewers assessed the studies for eligibility. RESULTS: Cross-sectional: 211 OP-SCC (63.0%) and 124 benign lesions (37.0%) were included. OP-SCC frequency increased gradually over time, whereas benign lesions had steady trends. OP-SCC affected more males (n= 171; 81.0%), though the relative frequency in females rose over time. Smoking (n= 127; 60.2%) was common in OP-SCC. Nineteen OP-SCC (13.0%) were positive for HPV. HPV-positive and HPV-negative tumors had similar clinicopathological features (p>0.05). Benign lesions predominated in middle-aged (n= 32; 26.7%) women (n= 71; 57.3%), in the soft palate (n=101; 81.5%). LITERATURE REVIEW: 32 studies were included, and in 60% of them, HPV frequency in OP-SCC was less than 25%. CONCLUSIONS: OP-SCC prevalence has been increasing, and it was mostly associated with smoking and alcohol rather than with HPV infection in Brazil. Benign lesions had a stationary frequency over the evaluated period.

Estimating the burden of care for oral potentially malignant disorders and oral cancer in Brazilian dental practice.

BACKGROUND: Oral cancer (OC) and oral potentially malignant disorders (OPMD) pose significant challenges to public health in Brazil. This study aimed to estimate the prevalence of oral cancer (OC) and oral potentially malignant disorders (OPMD) among patients who would be treated by Brazilian dentists during their careers. MATERIAL AND METHODS: Data on the number of dentists in Brazil were extracted from the 2022 census data, while incidence rates for OC cases were sourced from the Brazilian National Cancer Institute (INCA). Population estimates for Brazil and data on dental check-up rates were obtained from relevant national sources. RESULTS: Our analysis indicates that a general dentist in Brazil can expect to encounter on average two to three OC patients and on average 675 patients with OPMDs over a 35-year career. Regional disparities were observed, with certain regions showing higher than the average number of encounters due to low density of dentists in some rural districts. CONCLUSIONS: Brazilian dentists are likely to confront a substantial number of OC and OPMD cases during their professional tenure, emphasizing the need for public health policies aimed at enhancing dental surgeons' education in oral cancer prevention and early detection.

Spray skin protectant versus standard moisturiser in the prevention of radiodermatitis in patients with anal canal and rectal cancer: A randomised clinical trial.

The evidence on products for the prevention of radiodermatitis is limited. The primary objective was to analyse the effectiveness of the spray skin protectant 'non-burning barrier film' in the prevention of radiodermatitis with moist desquamation in patients with the anal canal and rectal cancer followed in nursing consultations compared to a standardised moisturiser based on Calendula officinalis and Aloe barbadensis. Single-blind randomised clinical trial. The study was performed in a hospital in Rio de Janeiro, Brazil, with 63 patients undergoing anal canal and rectal cancer treatment, randomised into one of the following two groups: an experimental group, which used a spray skin protectant and a control group, which used a moisturiser. Data were collected using an initial and subsequent evaluation form and were assessed using descriptive and inferential analyses. Participants who used the spray skin protectant had a lower chance of presenting radiodermatitis with moist desquamation and a longer time without this outcome when compared to the control group. The overall incidence of radiodermatitis was 100%, with 36.5% being severe. Furthermore, 17.5% of participants discontinued radiotherapy due to radiodermatitis. There were no differences between the groups regarding the severity of radiodermatitis and the number of patients who discontinued radiotherapy. The skin protectant was effective in preventing radiodermatitis with moist desquamation amongst patients with anal canal and rectal cancer.

Nodular type but not vitamin D levels increases the risk of second primary cancers in melanoma patients: An observational study of 663 patients.

BACKGROUND: Vitamin D deficiency associates with the risk of developing many diseases, including cancer. At the molecular level, vitamin D appears to have an antineoplastic effect. However, the role of vitamin D deficiency in cancer pathogenesis remains unelucidated and numerous studies have resulted in discordant results. This study aimed to determine whether vitamin D deficiency during melanoma diagnosis increases the risk of developing non-cutaneous second primary cancers (SPC). MATERIALS AND METHODS: A retrospective study on 663 patients diagnosed with melanoma between 1 January 2011 and 31 October 2022. The effect of each variable on the development of a subsequent non-cutaneous cancer was performed using Kaplan-Meier curves and differences were assessed by log-rank tests. Cox proportional hazard univariate and multivariate models were used to quantify the effect of each variable in the time to develop a non-cutaneous neoplasia. RESULTS: Out of 663 patients, 34 developed a non-cutaneous SPC. There was no statistically significant association between vitamin D levels and non-cutaneous SPC development (log-rank, p=0.761). Age>60 years, stage III/IV, and nodular melanoma subtype were significantly associated with the development of a SPC. After multivariate analysis, only age>60 years (HR 3.4; HR CI 95%: 1.5-7.6) and nodular melanoma subtype (HR 2.2; HR CI 95%: 1.0-4.8) were included in the final model. CONCLUSIONS: Our results suggest that vitamin D deficiency is not associated with an increased risk of developing non-cutaneous SPC in melanoma patients. However, age over 60 years and nodular melanoma subtype increase the risk for non-cutaneous SPC development.

Nodular Type but Not Vitamin D Levels Increases the Risk of Second Primary Cancers in Melanoma Patients: An Observational Study of 663 Patients. / [Artículo traducido] El melanoma de tipo nodular pero no los niveles de vitamina D aumenta el riesgo de desarrollar una segunda neoplasia no cutánea en pacientes con un melanoma: estudio observacional de 663 pacientes.

BACKGROUND: Vitamin D deficiency associates with the risk of developing many diseases, including cancer. At the molecular level, vitamin D appears to have an antineoplastic effect. However, the role of vitamin D deficiency in cancer pathogenesis remains unelucidated and numerous studies have resulted in discordant results. This study aimed to determine whether vitamin D deficiency during melanoma diagnosis increases the risk of developing non-cutaneous second primary cancers (SPC). MATERIALS AND METHODS: A retrospective study on 663 patients diagnosed with melanoma between 1 January 2011 and 31 October 2022. The effect of each variable on the development of a subsequent non-cutaneous cancer was performed using Kaplan-Meier curves and differences were assessed by log-rank tests. Cox proportional hazard univariate and multivariate models were used to quantify the effect of each variable in the time to develop a non-cutaneous neoplasia. RESULTS: Out of 663 patients, 34 developed a non-cutaneous SPC. There was no statistically significant association between vitamin D levels and non-cutaneous SPC development (log-rank, p=0.761). Age>60 years, stage III/IV, and nodular melanoma subtype were significantly associated with the development of a SPC. After multivariate analysis, only age>60 years (HR 3.4; HR CI 95%: 1.5-7.6) and nodular melanoma subtype (HR 2.2; HR CI 95%: 1.0-4.8) were included in the final model. CONCLUSIONS: Our results suggest that vitamin D deficiency is not associated with an increased risk of developing non-cutaneous SPC in melanoma patients. However, age over 60 years and nodular melanoma subtype increase the risk for non-cutaneous SPC development.

Interobserver variability in the histopathological evaluation of melanoma: analysis of 60 case reports.

INTRODUCTION: Since the field of dermatopathology is not an exact science, it is prone to personal subjectivity, which sometimes causes disagreements on the diagnosis and assessment of some histological features. In the case of melanoma, some variables such as regression are associated with low interobserver agreement. On the contrary, other variables such as the measurement of Breslow thickness show high reproducibility. OBJECTIVE: The main objective of our study was to investigate multiple features of 60 consecutive cases of melanoma to establish interobserver reproducibility. METHODS AND MAIN RESULTS: We conducted an observational and descriptive study at Hospital de Manises, Valencia, Spain, IVO Foundation, Valencia, Spain, and Hospital 12 de Octubre, Madrid, Spain. The mean level of agreement of all study variables was moderate (Cohen's kappa coefficient statistic = 0.5). The highest agreement corresponded to polypoid morphology, pigmentation, ulceration, and solar elastosis. On the other hand, the lowest level agreement was reached for the presence of cellular pleomorphism and tumor necrosis. CONCLUSIONS: Our mean level of agreement was moderate, which reflects that some of the measured characteristics such as cellular pleomorphism or the presence of necrosis cannot be used for future studies or must be redefined and their reproducibility, reestablished. When conducting a research study, it is necessary to analyze the study variables to demonstrate their validity to measure or classify a certain feature. It is also advisable to warrant that that the variables are reproducible to be able to use them for other studies or in the routine clinical practice.

Giants of the Amazon: How does environmental variation drive the diversity patterns of large trees?

For more than three decades, major efforts in sampling and analyzing tree diversity in South America have focused almost exclusively on trees with stems of at least 10 and 2.5 cm diameter, showing highest species diversity in the wetter western and northern Amazon forests. By contrast, little attention has been paid to patterns and drivers of diversity in the largest canopy and emergent trees, which is surprising given these have dominant ecological functions. Here, we use a machine learning approach to quantify the importance of environmental factors and apply it to generate spatial predictions of the species diversity of all trees (dbh ≥ 10 cm) and for very large trees (dbh ≥ 70 cm) using data from 243 forest plots (108,450 trees and 2832 species) distributed across different forest types and biogeographic regions of the Brazilian Amazon. The diversity of large trees and of all trees was significantly associated with three environmental factors, but in contrasting ways across regions and forest types. Environmental variables associated with disturbances, for example, the lightning flash rate and wind speed, as well as the fraction of photosynthetically active radiation, tend to govern the diversity of large trees. Upland rainforests in the Guiana Shield and Roraima regions had a high diversity of large trees. By contrast, variables associated with resources tend to govern tree diversity in general. Places such as the province of Imeri and the northern portion of the province of Madeira stand out for their high diversity of species in general. Climatic and topographic stability and functional adaptation mechanisms promote ideal conditions for species diversity. Finally, we mapped general patterns of tree species diversity in the Brazilian Amazon, which differ substantially depending on size class.

Ethanol Oxidation Reaction Mechanism on Gold Nanowires from Density Functional Theory.

Thin gold nanowires (NWs) are materials that could be used as support in different chemical reactions. Using density functional theory (DFT) it was shown that NWs that form linear atomic chains (LACs) are suitable for stimulating chemical reactions. To this end, the oxidation reaction of ethanol supported on the LACs of Au-NWs was investigated. Two types of LACs were used for the study, one pure and the other with an oxygen impurity. The results showed that the oxygen atom in the LAC fulfills important functions throughout the reaction pathway. Before the chemical reaction, it was observed that the LAC with impurity gains structural stability, that is, the oxygen acts as an anchor for the gold atoms in the LAC. In addition, the LAC was shown to be sensitive to disturbances in its vicinity, which modifies its nucleophilic character. During the chemical reaction, the oxidation of ethanol occurs through two different reaction paths and in two stages, both producing acetaldehyde (CH3 CHO). The different reaction pathways are a consequence of the presence of oxygen in the LAC (oxygen conditions the formation of reaction intermediates). In addition, the oxygen in the LAC also modifies the kinetic behavior in both reaction stages. It was observed that, by introducing an oxygen impurity in the LAC, the activation energy barriers decrease ∼69 % and ∼97 % in the first and second reaction stages, respectively.