Howler Monkey Die-Off in Southern Mexico.

In May and June 2024, a die-off of Mexican mantled howler monkeys (Alouatta palliata mexicana) occurred in southern Mexico. This commentary documents the event, attributing it to extreme heatwaves, drought, wildfires, and habitat impoverishment. Despite their reported resilience to habitat disturbances, mantled howler monkey mortality rate in some areas reached 31%. Key evidence points to heatstroke as the primary cause of death, exacerbated by limited hydration and reduced dietary diversity in disturbed habitats. Immediate responses included community-led rescues (e.g., hydrating the monkeys), coordination of rescue activities by nongovernmental organizations (NGOs) (e.g., managing donations), involvement of scientists (e.g., monitoring of primate populations), and assistance from government officials (e.g., providing legal support for animal management). This event underscores the urgency of developing action plans to prevent and attend future crises. Among other actions, we highlight (i) establishing primate care infrastructure with medical and rehabilitation centers; (ii) developing protocols and training programs to ensure rapid crisis response; (iii) fostering collaboration among government, NGOs, and academic institutions for effective crisis management; and (iv) developing targeted research on climate change impacts, predictive models, and long-term health monitoring. We emphasize the critical need for coordinated conservation efforts to protect wild primates and maintain natural ecosystem resilience in the face of escalating climate challenges.

The Vehicle of Administration and Prandial State May Reduce the Spectrum of Oral Broad-Spectrum Antibiotics (Oxytetracycline, Fosfomycin and Amoxicillin) Administered to Piglets: A Pharmacokinetic/Pharmacodynamic Approach.

The objective of this study was to assess the impact of the vehicle of administration and the prandial state of post weaning piglets on the indices of therapeutic efficacy for different broad-spectrum antibiotic/pathogen combinations. Pharmacokinetic data were retrieved from previous studies, in which we orally administered oxytetracycline (OTC), fosfomycin (FOS), or amoxicillin (AMX) according to the following treatments: dissolved in soft water to fasted or non-fasted piglets, dissolved in hard water to fasted or non-fasted piglets, and mixed with feed. Minimum inhibitory concentration (MIC) values for susceptible strains of bacteria causing swine diseases were obtained from the database of European Committee on Antimicrobial Susceptibility Testing (EUCAST) for each antibiotic. Pharmacokinetic/pharmacodynamic (PK/PD) indices of therapeutic efficacy-drug exposure over the dosing interval (fAUC/MIC) for OTC and FOS; time that free drug concentration remains above MIC (%fT>MIC) for AMX-were calculated for each antibiotic/pathogen combination under each treatment. After all OTC and in-feed FOS and AMX treatments, the indices of therapeutic efficacy were below the target value for all the study microorganisms. When FOS or AMX were delivered dissolved in soft or hard water, the indices were above the target value over which therapeutic efficacy would be expected for Escherichia coli treated with FOS and, Glaesserella parasuis, Pasteurella multocida, and Actinobacillus pleuropneumoniae treated with AMX. The prandial state of piglets showed no influence on the indices of therapeutic efficacy. Pharmacokinetic profiles of broad-spectrum antibiotics, specifically the ability to achieve target concentrations, may be largely reduced due to drug interactions with components present in feed or water resulting in a discrepancy with PK/PD principles of prudent and responsible use of antibiotics.

The vehicle of administration, feed or water, and prandial state influence the oral bioavailability of amoxicillin in piglets.

Feed and water components may interact with drugs and affect their dissolution and bioavailability. The impact of the vehicle of administration (feed and water) and the prandial condition of weaner piglets on amoxicillin´s oral bioavailability was evaluated. First, amoxicillin's in vitro dissolution and stability in purified, soft, and hard water, as well as release kinetics from feed in simulated gastric and intestinal media were assessed. Then, pharmacokinetic parameters and bioavailability were determined in fasted and fed pigs using soft water, hard water, or feed as vehicles of administration following a balanced incomplete block design. Amoxicillin showed similar dissolution profiles in soft and hard water, distinct from the dissolution profile obtained with purified water. Complete dissolution was only achieved in purified water, and merely reached 50% in soft or hard water. Once dissolved, antibiotic concentrations decreased by around 20% after 24 h in all solutions. Korsmeyer-Peppas model best described amoxicillin release from feed in simulated gastric and intestinal media. Feed considerably reduced antibiotic dissolution in both simulated media. In vivo, amoxicillin exhibited significantly higher bioavailability when delivered via water to fasted than to fed animals, while in-feed administration yielded the lowest values. All treatments showed a similar rate of drug absorption. In conclusion, we demonstrated that water and feed components, as well as feed present in gastrointestinal tract of piglets decrease amoxicillin´s oral bioavailability. Therefore, the use of oral amoxicillin as a broad-spectrum antibiotic to treat systemic infections in pigs should be thoroughly revised.

Synthesis and Characterization of Carbon-Based Quantum Dots and Doped Derivatives for Improved Andrographolide's Hydrophilicity in Drug Delivery Platforms.

Carbon-based quantum dots (CBQDs), sulfur-doped carbon-based quantum dots (S-CBQDs), and nitrogen-doped carbon-based quantum dots (N-CBQDs) have strong potential for drug delivery platforms. They were conjugated with andrographolide, a well-known hydrophobic drug, to study the concomitant changes in hydrophilicity. The interactions between these nanomaterials and the drug were studied by characterizing the optical and structural properties of the nanoparticles before and after coupling with the drug. It was found that the interaction of the drug with these nanomaterials produced noticeable changes in their optical and structural properties. Moreover, the partition coefficient for the nanocomposites was determined by NMR. The results indicate that conjugating the drug with the nanoparticles significantly enhanced its affinity for the aqueous phase, from 2.632 to 0.1117, thereby opening the possibility of using this approach for developing an effective drug delivery platform for this hydrophobic drug.

Entomopathogenic fungi for the control of larvae and adults of Aedes aegypti (Diptera: Culicidae) vector of dengue, chikungunya and Zika viruses in Mexico.

OBJECTIVE: To assess larvicide and adulticide activity of different native strains of fungi on Aedes aegypti. MATERIALS AND METHODS: Third instar larvae were exposed for 72 h at a concentration of 1x108 conidia/ml of 15 fungi; only fungi that significantly affected the larvae were evaluated against the adult phase at a concentration of 2x1010 conidia/ml. Mortality readings were performed at 24, 48, and 72 h for larvae, and every day to 30 days for adults. RESULTS: Trichoderma longibrachiatum, Aspergillus aculeatus, and Metarhizium anisopliae had the best larvicidal activity at 24 h of exposure (p<0.05), causing mortalities of 100, 72, and 62%, respectively. Adult mosquitoes were more affected by Gliocladium virens (45% mortality), M. anisopliae (30% mortality), and T. longibrachiatum (23.33% mortality). CONCLUSION: The larval stage of Ae. aegypti was more susceptible than the adult phase to the pathogenic action of native fungi, with T. longibrachiatum being with the highest virulence.

Fosfomycin modifies the replication kinetics of bovine alphaherpesvirus-1 and reduces the timing of its protein expression on bovine (MDBK) and human (SH-SY5Y) cell lines.

Bovine alphaherpesvirus 1 (BoAHV-1) predisposes cattle to respiratory secondary bacterial infections, which can be treated with the broad-spectrum antibiotic fosfomycin. This drug also suppresses NF-kB activity and pro-inflammatory responses. Therefore, cattle may be exposed to an interaction between the virus and the antibiotic which may have effects on it. The aim of this study was to determine the effect of calcium fosfomycin (580 µg/mL) on BoAHV-1 (moi = 0.1) replication. Two cell lines (MDBK and SH-SY5Y) were used in this study. Our results show that fosfomycin has novel properties. By MTT assay we have shown that it is non-cytotoxic for any of the cell lines. Extracellular and intracellular viral titers demonstrated that fosfomycin has a cell-type and time-dependent effect on BoAHV-1 replication. By direct immunofluorescence it was shown that it reduces the timing of BoAHV-1 protein expression, and by qPCR, we found that its effect on NF-kB mRNA expression depends on the cell type.

Evaluación química, nutricional in vitro e in situ de ensilado de papaya de desecho y pasto pangola

RESUMEN Objetivo. Caracterizar nutritivamente in vitro e in situ ensilados con 75% de papaya de desecho y 25% de pasto pangola como base y 3% de melaza de caña como aditivo. Materiales y métodos. Los silos en bolsa (50 kg) se fermentaron por 21 d para medir características de calidad (pH, nitrógeno amoniacal, materia seca (MS), ácido láctico y ácidos grasos volátiles (AGV)) y químicas (proteína cruda (PC), cenizas (Ce), fibra detergente neutro (FDN), fibra detergente ácido (FDA)). En la prueba in vitro se midió producción parcial a las 24, 48 y 72 h y acumulada a 72 h de biogás y metano, degradación de MS, FDN y FDA a las 72 h. La digestibilidad in situ se determinó a 3, 6, 9, 12, 24, 36, 72 y 96 h, así como la cinética de digestibilidad de los nutrientes (MS, PC, FDN, FDA y MO). Resultados. Las características de calidad se encuentran dentro de los rangos establecidos para considerar un buen ensilado. En el contenido químico sobresale 5.1% de PC y 70.0% de FDN. En las primeras 24 h, se produjo 72.3% de biogás y 70.5% de metano. Las degradaciones fueron de 64% para MS, 51% en FDN y 55% en FDA. La digestibilidad in situ a las 72 h mostró degradaciones de 63% para MS, 82% para PC, 49% para FDN y 47% para FDA. Conclusiones. La elaboración de ensilado con papaya de desecho y pasto pangola es una alternativa no convencional para la alimentación de rumiantes.

ABSTRACT Objective. To characterize in vitro and in situ nutritional characterization of silages with 75% papaya residues and 25% pangola grass as a base and 3% sugarcane molasses as an additive. Materials and methods. Bagged silos (50 kg) were fermented for 21 d to measure quality (pH, ammonia nitrogen, dry matter (DM), lactic acid and volatile fatty acids (VFA)) and chemical characteristics (crude protein (CP), ash (As), neutral detergent fiber (NDF), acid detergent fiber (ADF)). In the in vitro assay, partial production at 24, 48 and 72 h and cumulative production at 72 h of biogas and methane, DM, NDF and ADF degradation at 72 h were measured. In situ digestibility was determined at 3, 6, 9, 12, 24, 24, 24, 36, 72 and 96 h, and nutrient digestibility kinetics (DM, CP, NDF, ADF and OM). Results. The quality characteristics are within the established ranges for considering a good silage. In the chemical content, 5.1% CP and 70.0% NDF stand out. In the first 24 h, 72.3% biogas and 70.5% methane were produced. Degradations were 64% for DM, 51% for NDF and 55% for ADF. In situ digestibility at 72 h showed degradations of 63% for DM, 82% for CP, 49% for NDF and 47% for ADF. Conclusions. The preparation of silage with papaya and pangola grass residues is a non-conventional alternative for ruminant feeding.

Citrullinemia is a suitable biomarker for post weaning performance in piglets under intensive farming.

OBJECTIVE: To describe citrullinemia profiles during the weaning transition and correlate citrulline production with stress and growth in a commercial pig farm. ANIMALS: 240 healthy piglets of homogenous weight, weaned from second and third parity sows, were selected at weaning and subjected to the farm's routine management practices in May to July 2020 and May to July 2021. PROCEDURES: Piglets were weighed at weaning, then 15 and 49 days later in order to calculate daily weight gain during the first 15 and 49 days after weaning. Blood samples were collected from each piglet to determine citrulline and cortisol profiles during the early postweaning period. RESULTS: Citrullinemia decreased dramatically during the first week postweaning and then increased progressively to reach preweaning values by 15 days postweaning. Citrulline production during the first 2 weeks postweaning was negatively correlated with cortisol production (r: -0.2949) and positively correlated with mean daily weight gain during the first 15 (ρ: 0.5450) and 49 (ρ: 0.6603) days postweaning. CLINICAL RELEVANCE: Citrullinemia profile of piglets during the early postweaning period showed a temporal negative impact of stress (assessed by plasmatic cortisol levels) on intestinal enterocytes' mass and function, which resulted in a lower average daily weight gain. We demonstrated that a single biomarker, plasmatic citrulline, is useful to describe intestinal metabolism during the early postweaning period and that the greater the citrulline production during the first days after weaning, the higher the weight gain during the entire postweaning period.

Exome Sequencing Data Analysis and a Case-Control Study in Mexican Population Reveals Lipid Trait Associations of New and Known Genetic Variants in Dyslipidemia-Associated Loci.

Background: Plasma lipid levels are a major risk factor for cardiovascular diseases. Although international efforts have identified a group of loci associated with the risk of dyslipidemia, Latin American populations have been underrepresented in these studies. Objective: To know the genetic variation occurring in lipid-related loci in the Mexican population and its association with dyslipidemia. Methods: We searched for single-nucleotide variants in 177 lipid candidate genes using previously published exome sequencing data from 2838 Mexican individuals belonging to three different cohorts. With the extracted variants, we performed a case-control study. Logistic regression and quantitative trait analyses were implemented in PLINK software. We used an LD pruning using a 50-kb sliding window size, a 5-kb window step size and a r2 threshold of 0.1. Results: Among the 34251 biallelic variants identified in our sample population, 33% showed low frequency. For case-control study, we selected 2521 variants based on a minor allele frequency ≥1% in all datasets. We found 19 variants in 9 genes significantly associated with at least one lipid trait, with the most significant associations found in the APOA1/C3/A4/A5-ZPR1-BUD13 gene cluster on chromosome 11. Notably, all 11 variants associated with hypertriglyceridemia were within this cluster; whereas variants associated with hypercholesterolemia were located at chromosome 2 and 19, and for low high density lipoprotein cholesterol were in chromosomes 9, 11, and 19. No significant associated variants were found for low density lipoprotein. We found several novel variants associated with different lipemic traits: rs3825041 in BUD13 with hypertriglyceridemia, rs7252453 in CILP2 with decreased risk to hypercholesterolemia and rs11076176 in CETP with increased risk to low high density lipoprotein cholesterol. Conclusions: We identified novel variants in lipid-regulation candidate genes in the Mexican population, an underrepresented population in genomic studies, demonstrating the necessity of more genomic studies on multi-ethnic populations to gain a deeper understanding of the genetic structure of the lipemic traits.

Effect of Dietary Oregano (Lippia origanoides) and Clover (Eugenia caryophillata) Essential Oils' Formulations on Intestinal Health and Performance of Pigs.

The incorporation of natural essential oils to the pigs' diet in intensive production systems is a potential tool to improve gut health and prevent infections without using antibiotics. Nevertheless, different products, even containing the same compounds, coming from the same botanical species, may exert dissimilar biological effects due differences in the technological processes by which they are produced and preserved. For this reason, suitability of a given product based on natural extracts, intended for swine production must be thoroughly evaluated. In the present study, we assessed the effects of three additives containing oregano (Lippia origanoides) essential oil, alone or in combination with clover (Eugenia caryophillata) essential oil, with or without being microencapsulated, on gastrointestinal health and on some performance parameters in a commercial pig production farm. Recently weaned piglets were randomly divided in four groups, and basal diet or essential oil-supplemented diet (OCE; MOCE; MOE) was randomly assigned to each of the groups from weaning to finishing. Blood samples were collected at pre-established days after weaning. Intestinal sampling took place at 42 and 72 days of age. Pigs consuming the supplemented diets showed higher intestinal metabolic activity during the post-weaning period, decreasing the impact of weaning stress on enterocytes' metabolism. Intestinal barrier function was not affected in pigs consuming microencapsulated products. All treated groups showed improved intestinal architecture, increased digestive enzymes activity and caecal VFA concentrations. The incorporation of the dietary essential oils products brought beneficial effects on gastrointestinal health that were reflected in improved performance parameters.

The genomic landscape of Mexican Indigenous populations brings insights into the peopling of the Americas.

The genetic makeup of Indigenous populations inhabiting Mexico has been strongly influenced by geography and demographic history. Here, we perform a genome-wide analysis of 716 newly genotyped individuals from 60 of the 68 recognized ethnic groups in Mexico. We show that the genetic structure of these populations is strongly influenced by geography, and our demographic reconstructions suggest a decline in the population size of all tested populations in the last 15-30 generations. We find evidence that Aridoamerican and Mesoamerican populations diverged roughly 4-9.9 ka, around the time when sedentary farming started in Mesoamerica. Comparisons with ancient genomes indicate that the Upward Sun River 1 (USR1) individual is an outgroup to Mexican/South American Indigenous populations, whereas Anzick-1 was more closely related to Mesoamerican/South American populations than to those from Aridoamerica, showing an even more complex history of divergence than recognized so far.

Potential interactions between an oral fosfomycin formulation and feed or drinking water: Impact on bioavailability in piglets.

Feed and drinking water are the most frequently used vehicles for administration of antibiotics in intensive pig production. Interactions of drugs with feed and water components may affect dissolution and bioavailability. Therefore, antibiotic formulations should be tested in order to assure their suitability for oral use. In this study, an oral fosfomycin (FOS) formulation was evaluated considering dissolution in water (soft and hard), release kinetics from feed in simulated gastrointestinal fluids and bioavailability after oral administration blended into feed or dissolved in water (soft and hard), to fed and fasted piglets. FOS reached immediate dissolution in soft and hard water. The presence of feed significantly decreased antibiotic dissolution in simulated intestinal medium. Bioavailability was lower when feed was used as a vehicle for FOS administration than when the drug was dissolved in water (soft or hard). The fed or fasted condition of piglets did not affect bioavailability. Probably, FOS interactions with feed components alter its dissolution in the gastrointestinal tract, and only a fraction of the dose would be available for absorption. This information must be considered to support decisions on eligibility of antibiotic pharmaceutical formulations and the vehicle for their administration in order to pursue a responsible use of antibiotics.

Transcriptional and epigenetic landscape of Ca2+-signaling genes in hepatocellular carcinoma.

Calcium (Ca2+) signaling has a major role in regulating a wide range of cellular mechanisms, including gene expression, proliferation, metabolism, cell death, muscle contraction, among others. Recent evidence suggests that ~ 1600 genes are related to the Ca2+ signaling. Some of these genes' expression is altered in several pathological conditions, including different cancer types, and epigenetic mechanisms are involved. However, their expression and regulation in hepatocellular carcinoma (HCC) and the liver are barely known. Here, we aimed to explore the expression of genes involved in the Ca2+-signaling in HCC, liver regeneration, and hepatocyte differentiation, and whether their expression is regulated by epigenetic mechanisms such as DNA methylation and histone posttranslational modifications (HPM). Results show that several Ca2+-signaling genes' expression is altered in HCC samples; among these, a subset of twenty-two correlate with patients' survival. DNA methylation correlates with eight of these genes' expression, and Guadecitabine, a hypomethylating agent, regulates the expression of seven down-regulated and three up-regulated genes in HepG2 cells. The down-regulated genes displayed a marked decrease of euchromatin histone marks, whereas up-regulated genes displayed gain in these marks. Additionally, the expression of these genes is modulated during liver regeneration and showed similar profiles between in vitro differentiated hepatocytes and liver-derived hepatocytes. In conclusion, some components of the Ca2+-signaling are altered in HCC and displayed a correlation with patients' survival. DNA methylation and HMP are an attractive target for future investigations to regulate their expression. Ca2+-signaling could be an important regulator of cell proliferation and differentiation in the liver.

Impact of water hardness on oxytetracycline oral bioavailability in fed and fasted piglets.

Water hardness is a critical factor that affects oxytetracycline dissolution by chelation with cations. These interactions may lead to impaired dosing and consequently decrease absorption. Moreover, feed present in gastrointestinal tract may interact with antibiotic and alter pharmacokinetic parameters. In the present study, dissolution profiles of an oxytetracycline veterinary formulation were assessed in purified, soft and hard water. Furthermore, oxytetracycline absolute bioavailability, after oral administration of the drug dissolved in soft or hard water, was evaluated in fed and fasted piglets. A maximum dissolution of 86% and 80% was obtained in soft and hard water, respectively, while in purified water dissolution was complete. Results from in vivo study reconfirmed oxytetracycline's very low oral bioavailability. The greatest values were attained when antibiotic was dissolved in soft water and in fasted animals. Statistically significant lower absolute bioavailability was achieved when hard water was used and/or animals were fed. Moreover, Cmax attained in all treatments was lower than MIC90 of most important swine pathogens. For these reasons, the oral use of OTC formulations, that have demonstrated low oral bioavailability, should be avoided to treat systemic diseases in pigs.

Effect of fosfomycin, Cynara scolymus extract, deoxynivalenol and their combinations on intestinal health of weaned piglets.

Weaning is a challenging stage of pig farming. Animals undergo environmental, social and dietary changes leading to weaning stress syndrome. In order to compensate for the detrimental effects of weaning stress, antibiotics and natural extracts are used as feed additives, sometimes without fully understanding the interactions between them or even with low concentrations of mycotoxins that are frequently present in feed. The aim of this study was to evaluate the effect of fosfomycin (FOS), Cynara scolymus extract (CSE), deoxynivalenol (DON) and their combined administration on intestinal health of weaned piglets. The experiment was designed as a 2 × 2 × 2 factorial arrangement with 3 factors (FOS, CSE and DON treatments), 2 levels each (presence and absence) and 3 repeats. Weaned piglets (n = 24) were randomly divided in groups to receive the different treatments, namely DON administered in diet (50 µg/kg BW), FOS administered into the drinking water (30 mg/kg BW), CSE administered in diet (15 mg/kg BW) and all their combinations. After 15 d, the animals were euthanized and gastrointestinal tract samples were immediately taken to evaluate gastrointestinal pH, Enterobacteriaceae to lactic acid bacteria (E:L) ratio, volatile fatty acid (VFA) concentrations, disaccharidase (lactase, sucrase and maltase) activity, histology (intestinal absorptive area [IAA] and goblet cells count) and mucus ability to adhere pathogenic Escherichia coli. From our results, FOS and CSE treatments, individually or combined, produced a lower E:L ratio, an enhanced production of butyrate, increased disaccharidase activity (particularly maltase), and a greater IAA and goblet cells count along with an increase in pathogenic bacteria adherence to intestinal mucus. Deoxynivalenol did not show interactions with the other factors and its administration produced decreases on VFA, disaccharidase activity and goblet cells count. In conclusion, weaning piglets receiving diets containing FOS, CSE or both exhibited evident beneficial intestinal effects compared to animals receiving diets free from these compounds. On the contrary, the presence of DON at sub-toxic concentrations produced detrimental effects on intestinal health. The knowledge of the physiological and pathological gut changes produced by these compounds contributes to understand their potential productive consequences.

Gene variants in AKT1, GCKR and SOCS3 are differentially associated with metabolic traits in Mexican Amerindians and Mestizos.

Amerindian ancestry appears to be a risk factor for metabolic diseases (MetD), making Mexicans an ideal population to better understand the genetic architecture of metabolic health. In this study, we determine the association of genetic variants previously reported with metabolic entities, in two Mexican populations, including the largest sample of Amerindians reported to date. We investigated the association of eigth single-nucleotide polymorphisms (SNPs) in AKT1, GCKR, and SOCS3 genes with different metabolic traits in 1923 Mexican Amerindians (MAs) belonging to 57 ethnic groups, and 855 Mestizos (MEZs). The allele frequency of 7/8 SNPs showed significant differences between MAs and MEZs. Interestingly, some alleles were monomorphic in particular ethnic groups, and highly frequent in other ones. With the exception of GCKR rs1260326T, as expected, all SNP frequencies in the MEZ population had intermediate values between its two main ancestral populations (MAs and Iberian populations in Spain [IBS]). We detected ethnic differences in linkage disequilibrium patterns and haplotype structure between MAs and MEZs, possibly due to the high genetic heterogeneity in these populations. Remarkably, AKT1 was associated with hypertension in MEZs, but not in MAs. GCKR was associated with protection against type 2 diabetes (T2D) in MAs, and with hypertriglyceridemia and protection against low HDL Cholesterol (HDL-C) levels in MEZs. The CAT haplotype in SOCS3 was associated with metabolic syndrome (MetS) in MEZs, and correlated with protection against high blood pressure (HBP) and risk for high waist circumference and T2D in MAs. Our results show differential genetic associations with metabolic traits between MAs and MEZs, possibly due to the differences in genetic structure between these Mexican populations.

Ex vivo penetration of fosfomycin into healthy and Lawsonia intracellularis-colonized swine intestinal mucosa.

Fosfomycin (FOS) is an antibiotic used, mostly in Latin America, for the treatment of lung and enteric infections of pigs. Intracellular fluids of enterocytes can act as biophase for Lawsonia intracellularis, the causative agent of porcine proliferative enteropathy (PPE). The aim of this study was to determine whether the presence of L. intracellularis in the enterocytes modifies FOS penetration. Eight healthy pigs in growth-finishing stage were used to produce healthy (group A) and L. intracellularis-colonized (group B) intestinal explants. For both groups, treatment consisted of a 580 µg/ml concentration of calcium FOS, which was added to each explant (0.5-6 hr). For group B, the Enterisol Ileitis® vaccine was used as source of the micro-organism. Previously to the assay, the time necessary for L. intracellularis to colonize the enterocytes was defined. Also, a PCR protocol was optimized to determine the presence of the pathogen in the explants. There were nonstatistical differences for the penetration of the antibiotic into healthy and L. intracellularis-colonized enterocytes. MIC90 of FOS for L. intracellularis is unknown; nevertheless, MIC90 of various antibiotics ranges between 0.125 and 128 µg/ml. FOS reaches inside the enterocyte concentrations which surpass the MICs90 of other antibiotics that also act by the inhibition of cell wall synthesis; however, further studies should be carried out to determine fosfomycin MIC90 for L. intracellularis to discern the usefulness of this antibiotic in the treatment of PPE.

Consumo de sustancias en adolescentes: consideraciones para la práctica médica / Substance use in adolescents: Considerations for medical practice

Resumen El consumo de sustancias entre jóvenes y adolescentes representa un importante problema de salud que se relaciona con lesiones y accidentes graves, discapacidad, trastornos por consumo de sustancias y otros trastornos psiquiátricos, ideación y conducta suicida, conductas sexuales de riesgo, entre otros. Se trata de un problema de salud pública que se ha incrementado de manera considerable en los últimos años. El objetivo de este artículo es revisar los aspectos generales del consumo de sustancias de abuso en adolescentes, como: epidemiología, factores de riesgo, tamizaje, evaluación, diagnóstico, algunas consideraciones para la referencia y tratamiento en un hospital general. Como resultado, se identificó que existen múltiples factores de riesgo del inicio del consumo de sustancias, así como de la aparición de un trastorno por consumo de sustancias. Entre éstos destacan factores individuales, familiares y medioambientales. Asimismo, se identificaron estrategias para la detección temprana, orientación y referencia a tratamiento integral, conocidos como SBIRT (de sus siglas en inglés de Screnning, Brief Intervention, Reference to Treatment). Por último se concluye que la implementación de programas SBIRT en un hospital general es eficaz para mejorar el vínculo entre los servicios del hospital y los programas especializados para tratamiento de los trastornos por consumo de sustancias.

Abstract Substance abuse among young adults and teenagers represents a considerable health issue, as substance use can be associated to serious injuries, accidents, disabilities, substance use and other psychiatric disorders, suicidal ideation and suicidal behavior, sexual risk practices, among others. In the last years, this health problem has been increasing significantly. The objective of this article is to present a review of general aspects of substance abuse in adolescents, such as: epidemiology, risk factors, screening, evaluation, diagnosis, some considerations for referral and general hospital treatment. As a result, it was found that several risk factors have been identified, such as individual, family and environmental factors. Also, strategies for early detection, counsel and reference to integrated treatment known as SBIRT (Screnning, Brief Intervention, Reference to Treatment) were identified. Finally, it is concluded that the implementation of SBIRT programs in general hospital are effective to improve the link between general hospital services to specialized programs for the treatment of substance use disorders.

Chlorogenic acid is a fungicide active against phytopathogenic fungi.

Plants synthesize diverse types of secondary metabolites and some of them participate in plant protection against pathogen attack. These compounds are biodegradable and renewable alternatives, which may be envisaged for the control of plant pests and diseases. Chlorogenic acid (CGA) is a phenolic secondary metabolite which accumulates in diverse plant tissues and can be found in several agro-industrial by-products and waste. The aim of this work was to determine whether CGA could control the growth of various plant pathogenic fungi, gaining insight into its mechanism of action. Microscopic analysis showed the complete inhibition of spore germination or reduction of mycelial growth for Sclerotinia sclerotiorum, Fusarium solani, Verticillium dahliae, Botrytis cinerea and Cercospora sojina. CGA concentrations that did not completely abolish spore germination were able to produce a partial inhibition of mycelial growth. Viability tests and vital dye staining demonstrate that CGA induces fungal cell lysis. Its fungicidal activity involves an early membrane permeabilization of the spores. These results show the antifungal activity of CGA against phytopathogenic fungi relevant in horticulture and agriculture highlighting the potential of CGA-enriched wastes and by-products to be used as biofungicides.

Effectiveness of Photodynamic Therapy in Elimination of HPV-16 and HPV-18 Associated with CIN I in Mexican Women.

This study aimed to determine the effectiveness of photodynamic therapy (PDT), using δ-aminolevulinic acid (5-ALA), in the elimination of premalignant cervical lesions in Mexican patients with human papillomavirus (HPV) infection and/or cervical intraepithelial neoplasia (CIN). Thirty women diagnosed with CIN I and/or positive for HPV participated in the study. Topical 6% 5-ALA in gel form was applied to the uterine cervix; after 4 h, the lesion area was irradiated with a light dose of 200 J cm-2 at 635 nm. This procedure was performed three times at 48-h intervals. Clinical follow-up was performed at 3, 6, and 12 months after the initial PDT administration, by colposcopy, cervical cytology, histopathological analysis, polymerase chain reaction, and hybrid capture. Of HPV-infected patients without evidence of CIN I, 80% cleared the infection, while HPV associated with CIN I was eliminated in 83% of patients (P < 0.05). At 12 months, CIN I had regressed in 57% of patients, although this response was not statistically significant. PDT using 6% 5-ALA is concluded to be effective in eliminating HPV infection associated or not with CIN I.