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The objective of this research was to develop a model for assessing the risk of erosion, exploring the potential of DEMs from SRTM, ASTER, ALOS PALSAR and one made with interpolation of a 1:25,000 contour map to calculate the variables of the relief that have greater impact on erosion. Several geomorphometric parameters, such as slope, aspect, profile and plan curvature, topographic wetness index, stream power index, and sediment transport capacity were computed from the DEM´s elevation, some fuzzy logic functions proposed to evaluate the incidence of each parameter on erosion risk in a mountainous area of Colombia. The results showed that the use of DEM data is a relatively easy, uncostly method to identify, in a qualitative way, the risk of erosion and contribute to the enhancement of erosion information that is obtained with conventional general soil surveys.

We evaluated the growth and survival of the mangrove oyster Crassostrea rhizophorae (30 mm maximum length) reared in two suspended-culture systems (raft and long-line) using three types of enclosures (oyster enclosures, lantern nets and enclosures based on crates used to transport fish), at a density of 750 ind m-2, in La Restinga Lagoon, Margarita Island, Venezuela, over the course of six months. No significant differences were found in shell growth (length and mass) due to the system and enclosures used; however, raft-cultured oysters showed better tissue growth. At the end of the study, the oysters in lantern nets suspended from rafts obtained a tissue mass that was around 40% higher than that of the rest of the oysters cultured in the other enclosures. Significant differences in oyster survival were not observed for the raft and long-line systems used, but the cumulative survival at the end of the study was significantly higher for the oyster enclosures (52-56%) than for the lantern nets (36-39%) and fish crates (24-25%). We therefore recommend employing rafts and discarding the use of crate-type enclosures in the culture of C. rhizophorae in lagoon systems. [ABSTRACT FROM AUTHOR]

Liposarcoma is one of the most common neoplasms of adulthood. However, it is exceedingly rare in the gastrointestinal tract. To our knowledge, only 12 cases occurring in the esophagus have been reported in the world literature to date. We report the case of a 42-year-old man with a pleomorphic liposarcoma arising in the esophageal wall. The morphologic, immunophenotypic, and ultrastructural characteristics are presented, as well as the results of literature review. [ABSTRACT FROM AUTHOR]

Background: Carbapenemase-producing Enterobacterales (CPE) represents a significant threat to global health. This study aimed to characterize clinically and molecularly the CPE isolated from rectal swabs of patients in the intensive care units (ICUs) of a tertiary hospital in Cali, Colombia., Methods: This was a cross-sectional observational study. Rectal swabs from patients admitted to the ICUs were collected. Bacterial identification and carbapenemase production were determined using phenotypic and molecular methods. Demographic and clinical data were extracted from electronic medical records., Results: The study included 223 patients. Thirty-six patients (36/223, 16.14 %) were found to be colonized or infected by CPE. Factors such as prolonged stay in the ICU, previous exposure to carbapenem antibiotics, use of invasive procedures, and admission due to trauma were associated with CPE. Klebsiella pneumoniae (52.5 %) was the most prevalent microorganism, and the dominant carbapenemases identified were KPC (57.8 %) and NDM (37.8 %)., Conclusion: Distinguishing carbapenemase subtypes can provide crucial insights for controlling dissemination in ICUs in Cali, Colombia., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Background: While cannabis is the most widely used recreational drug in the world, the effects of phytocannabinoids on semen parameters and reproductive hormones remain controversial. Cannabinoid receptors are activated by these compounds at each level of the hypothalamus-pituitary-gonadotropic axis., Objectives: To assess the impact of the consumption of Δ-9-tetrahydrocannabinol and cannabidiol on semen parameters, as well as on male reproductive hormone and endocannabinoid levels, in a cohort of young Swiss men., Materials and Methods: The individuals in a Swiss cohort were divided according to their cannabis consumption. In the cannabis user group, we determined the delay between the last intake of cannabis and sample collection, the chronicity of use and the presence of cannabidiol in the consumed product. Urinary Δ-9-tetrahydrocannabinol metabolites were quantified via gas chromatography-mass spectrometry. Blood phytocannabinoids, endocannabinoids and male steroids were determined via liquid chromatography-mass spectrometry/mass spectrometry, and other hypothalamus-pituitary-gonadotropic axis hormones were determined via immunoassays. Semen parameters such as sperm concentration and motility were recorded using computer-assisted sperm analysis., Results: Anandamide, N-palmitoyl ethanolamide, androgens, estradiol and sex hormone binding globulin levels were all higher in cannabis users, particularly in chronic, recent and cannabidiol-positive consumers. Gonadotropin levels were not significantly different in these user subpopulations, whereas prolactin and albumin concentrations were lower. In addition, cannabis users had a more basic semen pH and a higher percentage of spermatozoa with progressive motility. However, the two latter observations seem to be related to a shorter period of sexual abstinence in this group rather than to the use of cannabis., Conclusions: Because both cannabidiol and Δ-9-tetrahydrocannabinol are frequently used by men of reproductive age, it is highly relevant to elucidate the potential effects they may have on human reproductive health. This study demonstrates that the mode of cannabis consumption must be considered when evaluating the effect of cannabis on semen quality., (© 2023 American Society of Andrology and European Academy of Andrology.)

Introduction: Long-term use of antiretroviral therapy (ART) for HIV infection might lead to the necessity of switching regimens. We aimed to analyze the reasons for the ART switch, the time-to-switch of ART, and its associated factors in a Colombian cohort., Methods: We conducted a retrospective cohort in 20 HIV clinics, including participants ≥18 years old with confirmed HIV infection who underwent an ART switch from January 2017 to December 2019 with at least 6 months of follow-up. A time-to-event analysis and an exploratory Cox model were performed., Results: 796 participants switched ART during the study period. The leading cause of ART switch was drug intolerance ( n = 449; 56.4%) with a median time-to-switch of 12.2 months. The longest median time-to-switch was due to regimen simplification (42.4 months). People ≥50 years old (HR = 0.6; 95% CI (0.5-0.7) and CDC stage 3 at diagnosis (HR = 0.8; 95% CI (0.6-0.9) had less hazard for switching ART over time., Conclusions: In this Colombian cohort, drug intolerance was the main cause of the ART switch, and the time-to-switch is shorter than reports from other countries. In Colombia, it is crucial to apply current recommendations for ART initiation to choose regimens with a better tolerability profile., Competing Interests: Declaration of conflicting interestsThe author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: WL declares MSD unrestricted grant. MGG and SMV declare personal fees from MSD. SLVB and CAM declare MSD grant. CBR and JU are employees of MSD, Colombia, who may own stock and/or hold stock options in Merck and Co., Inc., Kenilworth, NJ USA. EM reports grants, personal fees and other from VIIV/ GSK, personal fees and other from Merck Sharp and Dohme Corp, personal fees and other from Biotoscana gilead group. SL was MSD employee during manuscript development SVC, MJR, LAM, MM, LMR, OS, JF, CG, NF, MB, JA, DA, JAA do not declare any conflict of interest.

Introduction: There is insufficient evidence supporting the use of rapid diagnostic tests (RDTs) for syphilis in people living with HIV (PLWH). We evaluated the diagnostic performance of two commercially available RDTs (Bioline and Determine) in PLWH in Cali, Colombia., Methods: A cross-sectional field validation study on consecutive adults with confirmed HIV diagnosis attending three outpatient clinics. Both RDTs were performed on capillary blood (CB), obtained by finger prick, and sera, by venipuncture. A combination of treponemal enzyme linked immunosorbent assay (ELISA) and Treponema pallidum haemagglutination assay (TPHA) on serum samples was the reference standard. Rapid plasma reagin (RPR) and clinical criteria were added to define active syphilis. Sensitivity and specificity, predictive values and likelihood ratios (LR) of RDTs were estimated with their corresponding 95% confidence interval (95% CI). Stratified analyses by sample type, patient characteristics, non-treponemal titers, operator and re-training were performed., Results: 244 PLWH were enrolled, of whom 112 (46%) had positive treponemal reference tests and 26/234 (11.1%) had active syphilis. The sensitivities of Bioline on CB and sera were similar (96.4% vs 94.6%, p = 0.6). In contrast, Determine had a lower sensitivity on CB than sera (87.5% vs 99.1%, p<0.001). Sensitivities were lower in PLWH not receiving ART (Bioline 87.1% and Determine 64.5%, p<0.001) and for one of the operators (Bioline 85% and Determine 60%, p<0.001). Specificities of the RDTs were > 95% in most analyses. Predictive values were 90% or higher. For active syphilis, the RDTs showed a similar performance pattern but with decreased specificities., Conclusion: The studied RDTs have an excellent performance in PLWH to screen for syphilis and potentially for active syphilis, yet Determine performs better on sera than CB. Patient characteristics and potential difficulties operators may face in acquiring enough blood volume from finger pricks should be considered for the implementation and the interpretation of RDTs., Competing Interests: The authors have declared that no competing interest exist., (Copyright: © 2023 García Luna et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

In human, Tyrosinase enzyme (TyH) is involved in the key steps of protective pigments biosynthesis (in skin, eyes and hair). The use of molecules targeting its binuclear copper active site represents a relevant strategy to regulate TyH activities. In this work, we targeted 2-Hydroxypyridine-N-oxide analogs (HOPNO, an established chelating group for the tyrosinase dicopper active site) with the aim to combine effects induced by combination with a reference inhibitor (kojic acid) or natural substrate (tyrosine). The HOPNO-MeOH (3) and the racemic amino acid HOPNO-AA compounds (11) were tested on purified tyrosinases from different sources (fungal, bacterial and human) for comparison purposes. Both compounds have more potent inhibitory activities than the parent HOPNO moiety and display strictly competitive inhibition constant, in particular with human tyrosinase. Furthermore, 11 appears to be the most active on the B16-F1 mammal melanoma cells. The investigations were completed by stereospecificity analysis. Racemic mixture of the fully protected amino acid 10 was separated by chiral HPLC into the corresponding enantiomers. Assignment of the absolute configuration of the deprotected compounds was completed, based on X-ray crystallography. The inhibition activities on melanin production were tested on lysates and whole human melanoma MNT-1 cells. Results showed significant enhancement of the inhibitory effects for the (S) enantiomer compared to the (R) enantiomer. Computational studies led to an explanation of this difference of activity based for both enantiomers on the respective position of the amino acid group versus the HOPNO plane., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Masson SAS. All rights reserved.)

In 2019, Colombia approved the combination of tenofovir disoproxil fumarate/emtricitabine for HIV Pre-Exposure Prophylaxis (PrEP). Therefore, we conducted a situational analysis in HIV-care providers to identify barriers and facilitators for PrEP implementation. A survey was applied to a non-probabilistic sample of health care workers of HIV-specialized clinics. We examined PrEP awareness and familiarity, comfort with PrEP-related activities, perceived barriers for PrEP implementation, concerns, and attitudes. Poisson regressions assessed the relationship between these factors and the variable "having a plan to offer PrEP". The participation rate was 41% and included physicians (42.6%) and other health professionals (57.4%). Fifty-one percent of the participants reported more than five years of experience caring for people living with HIV. Forty-two percent of non-physician health care workers were nurses. Most reported high familiarity/comfort with PrEP-relevant activities. Concerns about PrEP were prevalent (> 50%) and included causing more harm than good, reducing condom use, medication non-adherence, drug resistance, and healthcare system barriers. Physicians had a plan to offer PrEP (72.2%) more often than other health professionals (52.6). Having a plan to offer PrEP was related to PrEP knowledge and comfort assessing sexual behavior and providing HIV counseling. Overall, about half of HIV-care providers seemed ready to offer PrEP and constitute an asset for PrEP implementation efforts in Colombia. PrEP awareness among non-physicians, PrEP concerns, and negative attitudes need to be addressed to enhance implementation.

Social movements and the consequences of the current health crisis resulting from COVID-19 have deepened social injustices and inequities, which can be addressed through the benchmarks set by the Sustainable Development Goals (SDGs). This research is related to the perspective of Higher Education Institutions (HEIs) as social transformation agents. The purpose of this research is to create a scale to measure students' perception of the social responsibilities developed by HEIs from the SDGs' perspective. A matrix solution was found after Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA) composed of four dimensions. The constructs that form the four dimensions can be used to design strategies which contribute to the SDGs' goals, for which it is necessary to have the opinions of the actors that are part of the educational community. Future research should consider carrying out comparative studies according to sociodemographic variables for a better understanding of the social phenomenon.

Research in nanoscience continues to bring forward a steady stream of new nanomaterials and processes that are being developed and marketed. While scientific committees and expert groups deal with the harmonization of terminology and legal challenges, risk assessors in research labs continue to have to deal with the gap between regulations and rapidly developing information. The risk assessment of nanomaterial processes is currently slow and tedious because it is performed on a material-by-material basis. Safety data sheets are rarely available for (new) nanomaterials, and even when they are, they often lack nano-specific information. Exposure estimations or measurements are difficult to perform and require sophisticated and expensive equipment and personal expertise. The use of banding-based risk assessment tools for laboratory environments is an efficient way to evaluate the occupational risks associated with nanomaterials. Herein, we present an updated version of our risk assessment tool for working with nanomaterials based on a three-step control banding approach and the precautionary principle. The first step is to determine the hazard band of the nanomaterial. A decision tree allows the assignment of the material to one of three bands based on known or expected effects on human health. In the second step, the work exposure is evaluated and the processes are classified into three "nano" levels for each specific hazard band. The work exposure is estimated using a laboratory exposure model. The result of this calculation in combination with recommended occupational exposure limits (rOEL) for nanomaterials and an additional safety factor gives the final "nano" level. Finally, we update the technical, organizational, and personal protective measures to allow nanomaterial processes to be established in research environments.

Background: Autism spectrum disorder (ASD) is a complex neurodevelopmental condition characterized by persistent deficits in social communication and interaction. Common genetic variation appears to play a key role in the development of this condition. In this systematic review, we describe the relationship between genetic variations and autism. We created a gene dataset of the genes involved in the pathogenesis of autism and performed an over-representation analysis to evaluate the biological functions and molecular pathways that may explain the associations between these variants and the development of ASD., Results: 177 studies and a gene set composed of 139 were included in this qualitative systematic review. Enriched pathways in the over-representation analysis using the KEGG pathway database were mostly associated with neurotransmitter receptors and their subunits. Major over-represented biological processes were social behavior, vocalization behavior, learning and memory. The enriched cellular component of the proteins encoded by the genes identified in this systematic review were the postsynaptic membrane and the cell junction., Conclusions: Among the biological processes that were examined, genes involved in synaptic integrity, neurotransmitter metabolism, and cell adhesion molecules were significantly involved in the development of autism., (© 2021. The Author(s).)

Tyrosinase enzymes (Tys) are involved in the key steps of melanin (protective pigments) biosynthesis and molecules targeting the binuclear copper active site on tyrosinases represent a relevant strategy to regulate enzyme activities. In this work, the possible synergic effect generated by a combination of known inhibitors is studied. For this, derivatives containing kojic acid (KA) and 2-hydroxypyridine-N-oxide (HOPNO) combined with a thiosemicarbazone (TSC) moiety were synthetized. Their inhibition activities were evaluated on purified tyrosinases from different sources (mushroom, bacterial, and human) as well as on melanin production by lysates from the human melanoma MNT-1 cell line. Results showed significant enhancement of the inhibitory effects compared with the parent compounds, in particular for HOPNO-TSC. To elucidate the interaction mode with the dicopper(II) active site, binding studies with a tyrosinase bio-inspired model of the dicopper(II) center were investigated. The structure of the isolated adduct between one ditopic inhibitor (KA-TSC) and the model complex reveals that the binding to a dicopper center can occur with both chelating sites. Computational studies on model complexes and docking studies on enzymes led to the identification of KA and HOPNO moieties as interacting groups with the dicopper active site., (© 2020 Wiley-VCH GmbH.)

Throughout the COVID-19 pandemic, the main risk factors associated with the progression to severe disease or death have been typically advanced age, diabetes mellitus, obesity, high blood pressure, heart disease, and chronic pneumopathy. Because of their immunosuppression status, persons with HIV were also expected to have a higher susceptibility to infection or a poor clinical evolution. So far, this has not been confirmed to happen, giving way to hypotheses about the role of immunosuppression or the use of antiretrovirals, which could explain this paradox. In this article we present the existing data on the epidemiology and characteristics of HIV-COVID-19 co-infection, discuss the available evidence on the possible factors involved in the evolution of individuals affected by both viruses, analyze other determinants that may negatively affect persons with HIV during the pandemic, and present recommendations for the prevention and care of COVID-19 infection in the context of HIV., (Copyright © 2020 Colombia Medica.)

Background: The HLA-B*57:01 allele is associated with a hypersensitivity reaction to abacavir. Due to the lack of knowledge of HLA-B*57:01 prevalence in Colombia, routine screening is not performed and is not recommended by the national guidelines. We aimed to determine the prevalence of HLA-B*57:01 in HIV population from Colombia., Methods: This cross-sectional study included naïve HIV-infected adults from 13 cities of the country. The presence of HLA-B*57:01 was determined by using SSP-PCR in blood samples. Prevalence rates were stratified by sex, race, and region of origin., Results: HLA-B*57:01 allele prevalence in Colombian HIV-infected individuals was 2.7%. When stratifying for the race, the prevalence was 4% for whites, 2.6% for other race (mainly mestizo), and 1.9% for Afro-Colombians. The prevalence varied from 0% up to 11.4% depending on the department of origin. The highest prevalence rates were found in Caldas (11.4%), Antioquia (5%), Risaralda (4.8%), and Valle del Cauca (4.3%). When distributed by country zones, the central, with a racial predominance of Caucasians and mestizos, was the highest (6.0%, 0R = 4.1, CI 1.2-12.8, p = 0,016)., Conclusions: The overall prevalence of HLA-B*57:01 in Colombia was lower than the reported rates for other Latin American countries such as Brazil, Costa Rica, and Argentina, but similar in comparison to Chile and Mexico. The diversity in the racial and ethnic heritage shown in our data supports the recommendation to implement routine screening for the HLA-B*57:01 allele before initiation of abacavir-containing antiretroviral therapy in the Colombian HIV management guidelines.

Silicon nanowire (Si NW) sensors have attracted great attention due to their ability to provide fast, low-cost, label-free, real-time detection of chemical and biological species. Usually configured as field effect transistors (FETs), they have already demonstrated remarkable sensitivity with high selectivity (through appropriate functionalisation) towards a large number of analytes in both liquid and gas phases. Despite these excellent results, Si NW FET sensors have not yet been successfully employed to detect single molecules of either a chemical or biological target species. Here we show that sensors based on silicon junctionless nanowire transistors (JNTs), the simplest possible transistors, are capable of detecting the protein streptavidin at a concentration as low as 580 zM closely approaching the single molecule level. This ultrahigh detection sensitivity is due to the intrinsic advantages of junctionless devices over conventional FETs. Apart from their superior functionality, JNTs are much easier to fabricate by standard microelectronic processes than transistors containing p-n junctions. The ability of JNT sensors to detect ultra-low concentrations (in the zeptomolar range) of target species, and their potential for low-cost mass production, will permit their deployment in numerous environments, including life sciences, biotechnology, medicine, pharmacology, product safety, environmental monitoring and security.