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1.
Tob Induc Dis ; 222024.
Article in English | MEDLINE | ID: mdl-38828079

ABSTRACT

INTRODUCTION: Electronic cigarettes (e-cigarettes) have emerged as a new paradigm in nicotine delivery systems. Although they are marketed as safer alternatives to tobacco, public perceptions of their safety and utility vary widely. This study aims to understand the percentage of use, factors associated, perceptions, and attitudes about e-cigarettes among Ecuadorian adults. METHODS: A cross-sectional survey was conducted among the Ecuadorian population aged 18-65 years through a convenience sample, using a structured online questionnaire designed to collect responses from voluntary participants over three months, from February to April 2023. The questionnaire assessed the respondents' attitudes and perceptions towards e-cigarettes. Data were analyzed using descriptive statistics, chi-squared tests, and adjusted logistic regression analyses to identify factors associated with e-cigarette use. RESULTS: Out of a total of 3047 Ecuadorian adults, the percentage of e-cigarette ever use was 27.9% (n=850), with 19.4% being current users and 8.5% former users. A negative stance towards e-cigarettes was predominant, with 66.3% considering e-cigarette use a public health problem in Ecuador. A significant association was observed between e-cigarette use and perceived harmfulness (p<0.001). Among non-users, there was a predominant stance in favor of control measures and disapproval of e-cigarette use among minors (p<0.001). The factors associated with the use of electronic cigarettes included being health personnel (AOR=1.51; 95% CI: 1.26-1.80). Older age (aged >24 years) and a history of tobacco use were associated with lower e-cigarette use (current users, OR=0.31; 95% CI: 0.25-0.38; previous users, OR=0.23; 95% CI: 0.18-0.28). CONCLUSIONS: The findings highlight a significant percentage of e-cigarette use among Ecuadorian adults, especially among younger groups. There is a need for comprehensive public health education about e-cigarettes in Ecuador. There is strong support from the public for control measures, suggesting the potential acceptability of regulations concerning e-cigarettes.

2.
Front Plant Sci ; 15: 1371123, 2024.
Article in English | MEDLINE | ID: mdl-38721332

ABSTRACT

We aimed to evaluate the facilitation effects of an aluminum (Al) hyperaccumulator species bearing cluster roots, Gevuina avellana, on the seedling growth and performance of an Al-intolerant and phosphorus (P)-deficient-sensitive plant, Vaccinium corymbosum. For this, seedlings of G. avellana and V. corymbosum were grown alone or together as follows: i) two G. avellana seedlings, ii) one G. avellana + one V. corymbosum and iii) two V. corymbosum, in soil supplemented with Al (as Al2(SO4)3) and in the control (without Al supplementation). We determined relative growth rate (RGR), photosynthetic rate, chlorophyll concentration, lipid peroxidation and Al and nutrient concentration [Nitrogen (N), P, potassium (K), calcium (Ca), magnesium (Mg), sodium (Na), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), and sulfur (S)] in leaves and roots of both species. The results showed that, in general, G. avellana did not assist V. corymbosum to enhance its RGR nor reduce its Al uptake. However, G. avellana assisted V. corymbosum in enhanced N acquisition and, consequently, to increase its chlorophyll concentration and photosynthetic rate. Besides, V. corymbosum had lower lipid peroxidation in leaves when grown in the soil with high Al supplementation in association with G. avellana. Our results suggest a facilitating effect of G. avellana to V. corymbosum when grown in soils with high Al concentration, by enhancing chlorophyll concentrations and photosynthetic rate, and decreasing the oxidative damage to lipids.

3.
Acta Ortop Mex ; 38(1): 48-51, 2024.
Article in Spanish | MEDLINE | ID: mdl-38657151

ABSTRACT

Long COVID is a term used to describe the long-terms effects of COVID-19 infection that continue for weeks or months after the patient has recovered from COVID-19. Long COVID is defined by the persistence of symptoms beyond 12 weeks from the onset of the disease. Corticosteroids are part of the treatment in this period with good results in controlling the disease; however, it is a predisposing factor for the development of avascular necrosis. We present a clinic case of a young man of 39 years old with diagnosis of avascular necrosis in his left hip, before the administration of corticosteroids for the treatment of COVID-19. There is a lack of consensus about the dosage and duration of steroids required to develop avascular necrosis. Some authors have reported that cumulative dose of 2,000 mg prednisone (or its equivalent) was required for avascular necrosis development. For patients with advanced avascular necrosis stages total hip arthroplasty is an attractive option with excellent outcomes in terms of pain relief and survivorship.


El COVID de larga duración es un término que describe la enfermedad en pacientes que se recuperaron de una infección por COVID-19 y reportan síntomas por más de 12 semanas. Los corticosteroides forman parte del tratamiento en este período con buenos resultados en el control de la enfermedad; sin embargo, el uso de este grupo de medicamentos se ha descrito como un factor de riesgo para el desarrollo de necrosis avascular. Se describe el caso clínico de un paciente masculino de 39 años con diagnóstico de necrosis avascular de la cadera izquierda posterior a la administración de corticosteroides para el tratamiento de COVID-19. La dosis de esteroides capaz de provocar necrosis avascular no está clara o bien descrita; sin embargo, existen reportes en la literatura donde se habla de dosis de 2,000 mg de prednisona (o equivalentes) para su desarrollo. El tratamiento de la necrosis avascular tiene como objetivo el alivio del dolor, retardar la progresión del cuadro, prevenir el colapso en etapas tempranas y restaurar la función articular. La artroplastía o recambio total de cadera parece ser una excelente opción de tratamiento quirúrgico para aquellos pacientes en etapas avanzadas.


Subject(s)
COVID-19 , Femur Head Necrosis , Humans , Male , COVID-19/complications , Adult , Femur Head Necrosis/etiology , Femur Head Necrosis/surgery , Time Factors , Arthroplasty, Replacement, Hip , Glucocorticoids/therapeutic use , Glucocorticoids/administration & dosage
4.
Rev Gastroenterol Mex (Engl Ed) ; 89(1): 121-143, 2024.
Article in English | MEDLINE | ID: mdl-38580493

ABSTRACT

INTRODUCTION: Gastroesophageal reflux disease (GERD) is very prevalent in the general population, with a broad spectrum of clinical manifestations, requiring accurate diagnosis and treatment. AIM: The aim of this expert review is to establish good clinical practice recommendations for the diagnosis and personalized treatment of GERD. METHODS: The good clinical practice recommendations were produced by a group of experts in GERD, members of the Asociación Mexicana de Gastroenterología (AMG), after carrying out an extensive review of the published literature and discussing each recommendation at a face-to-face meeting. This document does not aim to be a clinical practice guideline with the methodology such a document requires. RESULTS: Fifteen experts on GERD formulated 27 good clinical practice recommendations for recognizing the symptoms and complications of GERD, the rational use of diagnostic tests and medical treatment, the identification and management of refractory GERD, the overlap with functional disorders, endoscopic and surgical treatment, and GERD in the pregnant woman, older adult, and the obese patient. CONCLUSIONS: An accurate diagnosis of GERD is currently possible, enabling the prescription of a personalized treatment in patients with this condition. The goal of the good clinical practice recommendations by the group of experts from the AMG presented in this document is to aid both the general practitioner and specialist in the process of accurate diagnosis and treatment, in the patient with GERD.


Subject(s)
Gastroesophageal Reflux , Aged , Female , Humans , Pregnancy , Endoscopy , Gastroesophageal Reflux/diagnosis , Gastroesophageal Reflux/therapy
5.
J Parasitol ; 110(2): 106-113, 2024 03 01.
Article in English | MEDLINE | ID: mdl-38503316

ABSTRACT

The acaricidal effect of 14 strains of Metarhizium anisopliae sensu lato isolated from soil of livestock farms in the Mexican tropics was evaluated against larvae and engorged females, and during the laying and hatching of eggs of Rhipicephalus microplus (Ixodida: Ixodidae). For each fungal strain, the larvae mortality percentage was evaluated through a larval immersion test, while the reproductive efficiency indices in engorged females were measured using adult immersion tests at a dose of 1 × 108 conidia/ml. All strains of M. anisopliae (s.l.) proved to be highly effective against R. microplus larvae (66-100%) and engorged females (100%). The strains also showed a good effect in inhibiting egg laying (16.45-56.38%) and a moderate effect in decreasing egg hatching (5.24-32.68%). Two strains demonstrated to be effective against all development phases of R. microplus in an integrated manner.


Subject(s)
Metarhizium , Rhipicephalus , Animals , Female , Rhipicephalus/microbiology , Livestock , Larva/microbiology , Pest Control, Biological , Reproduction
7.
Rev Gastroenterol Mex (Engl Ed) ; 89(1): 70-79, 2024.
Article in English | MEDLINE | ID: mdl-37225537

ABSTRACT

INTRODUCTION: Chronic idiopathic constipation (CIC) negatively impacts quality of life and increases healthcare costs. Lubiprostone stimulates the secretion of intestinal fluid, in turn facilitating the passage of stools and alleviating associated symptoms. Lubiprostone has been available in Mexico since 2018, but its clinical efficacy has not been studied in a Mexican population. AIM: To evaluate the efficacy of lubiprostone, assessed by changes in spontaneous bowel movement (SBM) frequency after one week of treatment with 24 µg oral lubiprostone (b.i.d.), as well as its safety, over four weeks of treatment. STUDY: Randomized, double-blind, placebo-controlled study on 211 adults with CIC in Mexico. RESULTS: The increase in SBM frequency, after one week of treatment, was significantly higher in the lubiprostone group than in the placebo group (mean: 4.9 [SD: 4.45] vs. 3.0 [3.14], p = 0.020). Secondary efficacy endpoints revealed a significantly higher proportion of SBM frequency/week in the lubiprostone group at weeks 2, 3, and 4. There was a better response within 24 h after the first dose with lubiprostone vs. placebo (60.0% vs. 41.5%; OR: 2.08, CI95%: [1.19, 3.62], p = 0.009) and the lubiprostone group also had significant improvement, with respect to straining, stool consistency, abdominal bloating, and Satisfaction Index. The main adverse events were gastrointestinal disorders in 13 (12.4%) lubiprostone-treated subjects and 4 (3.8%) control subjects. CONCLUSIONS: Our data confirm the efficacy and safety of lubiprostone for the treatment of CIC in a Mexican population. Lubiprostone treatment induces relief from the most bothersome symptoms associated with constipation.

8.
Semergen ; 50(2): 102123, 2024 Mar.
Article in Spanish | MEDLINE | ID: mdl-37939524

ABSTRACT

INTRODUCTION: Handgrip strength is a robust indicator of the biological health of elderly. OBJECTIVE: The purpose of this study is twofold: 1) estimate the normative values of absolute and relative handgrip strength, specific to adults over 60 years of age in Colombia, using quantile regression models: 2) compare the normative values of absolute and relative handgrip strength in Colombian older adults with those from different countries. METHODS: A cross-sectional analysis of a sample of 5377 older adults. Handgrip strength was evaluated with a TKK 5101 digital dynamometer (Takei Scientific Instruments Co., Ltd., Tokyo, Japan). Relative handgrip strength was estimated by dividing by weight in kilograms. The absolute and relative handgrip strength normative values were estimated through quantile regression models for the percentiles P5, P10, P25, P50, P75, P90 and P95, they were developed independently for each sex; all analyzes were adjusted for the expansion factor. RESULTS: Absolute handgrip strength values were considerably higher in men (P50 60-64 years = 32.0 kg, P50 >85 years = 18.0 kg) compared to women (P50 60-65 years = 19.0 kg; P50 >85 years = 12.0 kg), in all age groups. Additionally, as age increases in both sexes, there is a decrease in the values of absolute and relative manual grip strength. CONCLUSIONS: The estimated normative values in the Colombian population were generally lower than those reported in other studies around the world. These results could be related with methodologies used variability to evaluate handgrip strength and the estimation methods, which could influence the discrepancies between the different reports.


Subject(s)
Hand Strength , Sexual Behavior , Male , Aged , Humans , Female , Middle Aged , Colombia , Cross-Sectional Studies
9.
Acta Ortop Mex ; 37(2): 85-93, 2023.
Article in Spanish | MEDLINE | ID: mdl-37871931

ABSTRACT

INTRODUCTION: to evaluate the long term radiographic and functional results achieved in adult patients with osteoporotic, atrophic, non-unions of the diaphyseal humerus, treated surgically by open reduction and internal fixation with plates and bone graft. MATERIAL AND METHODS: we retrospectively evaluated 22 patients. Patient's age averaged 72 years. Time from initial trauma to definitive surgery averaged 18 months. Eleven patients were smokers, and four had active infection. Pre-operative Constant score and DASH score averaged 23.13 and 81.04, respectively. Pre-operative pain scale averaged 7.45 points. RESULTS: follow-up averaged 69 months. Union was achieved in all cases after an average of 4.68 months. DASH score at last follow-up averaged 20.27 points and Constant score 79.31 points. Analog pain scale averaged 0.77 points. Stabilization was performed using locking blade plates in 12 non-unions, locking compression plates in six cases, and double plating in four non-unions. Patients with active infection were treated in two stages using Masquelet's technique. Bone graft was associated in all cases (cancellous iliac crest autograft in 17, allograft in three, and combined structural allograft and cancellous autograft in two). Two grams of vancomycin powder were associated to the bone graft in all cases. CONCLUSION: the use of open reduction and internal fixation with plates associated to bone graft with local antibiotics, aloud achieving bony union and good predictable long-term objective and subjective functional results in all cases, without major complications or the need of further surgical intervention.


INTRODUCCIÓN: evaluar los resultados radiográficos y funcionales obtenidos a largo plazo en pacientes adultos que presentaron no-consolidaciones atróficas diafisarias de húmero asociadas a osteoporosis; tratadas quirúrgicamente mediante reducción abierta y fijación interna con placas e injerto óseo. MATERIAL Y MÉTODOS: evaluamos retrospectivamente 22 pacientes, con edad promedio de 72 años, el tiempo desde el trauma inicial hasta la cirugía definitiva promedió, 18 meses. Once pacientes eran fumadores y cuatro presentaban infección activa. El score de Constant y el DASH preoperatorios promediaron 23.13 y 81.04, respectivamente. El valor de la escala analógica del dolor preoperatorio promedió 7.45 puntos. RESULTADOS: el seguimiento promedió 69 meses. Se obtuvo la consolidación en todos los casos, luego de un promedio de 4.68 meses. Al último seguimiento, los valores del DASH promediaron 20.27 puntos y el score de Constant promedió 79.31 puntos. La escala analógica del dolor promedió 0.77 puntos. La estabilización se realizó utilizando clavos placa bloqueados en 12 no-consolidaciones, placas bloqueadas de compresión en seis y doble placa en cuatro. Los pacientes con infección activa fueron tratados en dos etapas utilizando la técnica descripta por Masquelet. Se asoció injerto óseo en todas las reconstrucciones (autoinjerto esponjoso de cresta ilíaca en 17, aloinjerto en tres y se combinó aloinjerto estructural con autoinjerto esponjoso en dos). Dos gramos de vancomicina en polvo fueron asociados localmente al injerto óseo. CONCLUSIÓN: la combinación de reducción abierta y fijación interna con placas e injerto óseo permitió obtener la consolidación y resultados funcionales objetivos y subjetivos buenos y predecibles a largo plazo en todos los casos, sin complicaciones mayores ni la necesidad de intervenciones quirúrgicas sucesivas.


Subject(s)
Fractures, Ununited , Adult , Humans , Aged , Fractures, Ununited/surgery , Retrospective Studies , Humerus , Fracture Fixation, Internal/methods , Reoperation
10.
Acta Ortop Mex ; 37(1): 30-35, 2023.
Article in Spanish | MEDLINE | ID: mdl-37857395

ABSTRACT

INTRODUCTION: osteoarthritis is one of the most prevalent chronic diseases in the world and is defined as the gradual loss of cartilage in the joints, mainly that of the knee. It is considered a cause of disability in older adults and is characterized by pain, stiffness and loss of mobility. MATERIAL AND METHODS: observational study to evaluate the effect of the combination of non-hydrolyzed type II native collagen (CII-NH), omega-3 (Om-3) and astaxanthin (AX), in a population of 182 patients with knee osteoarthritis grade I/II. Measurements of thigh circumference, arcs of movement and pain were obtained through international scales such as the visual analogue pain scale (VAS), the Lequesne index and the Western Ontario McMaster Universities Osteoarthritis Index (WOMAC) scale. Medical check-ups were performed every 30 days for three months. The Statgraphics software (Statgraphics Technologies, Virginia) was used, the evaluation of the variables and the statistical significance were determined by t Student test and the results are shown as a mean. RESULTS: it was shown that daily consumption increases mobility, decreases knee pain and inflammation in patients within three months. Additionally, there was a reduction in the consumption of nonsteroidal anti-inflammatory drugs (NSAIDs) by the study subjects. CONCLUSION: the fixed combination of non-hydrolyzed type II collagen, omega-3 and astaxanthin, generates, in the short term, a decrease in inflammation and stiffness in patients with osteoarthritis.


INTRODUCCIÓN: la osteoartritis es una de las enfermedades crónicas con mayor prevalencia en el mundo y se define como la pérdida gradual de cartílago en las articulaciones, principalmente la de rodilla. Es considerada como una causa de discapacidad en adultos mayores y se caracteriza por dolor, rigidez y pérdida de la movilidad. MATERIAL Y MÉTODOS: estudio observacional para evaluar el efecto de la combinación de Sólo debe decir, colágeno nativo tipo II, omega-3 (Om-3) y astaxantina (AX), en una población de 182 pacientes con artrosis de rodilla grado I/II. Se obtuvieron las mediciones de circunferencia del muslo, arcos de movimiento y dolor a través de las escalas internacionales como la escala visual analógica de dolor (EVA), el índice de Lequesne y escala Western Ontario McMaster Universities Osteoarthritis Index (WOMAC). Las revisiones médicas se realizaron cada 30 días durante tres meses. Se utilizó el software Statgraphics (Statgraphics Technologies, Virginia), la evaluación de las variables y la significancia estadística fueron determinadas por la prueba t de Student y los resultados se muestran como media. RESULTADOS: se demostró que el consumo diario incrementa la movilidad, disminuye el dolor y la inflamación de rodilla en los pacientes en un lapso de tres meses. Adicionalmente se registró una reducción en el consumo de antiinflamatorios no esteroideos (AINE) por parte de los sujetos de estudio. CONCLUSIÓN: la combinación fija colágeno nativo tipo II, omega-3 y astaxantina, genera, en el corto plazo, disminución de la inflamación y la rigidez en pacientes con osteoartritis.


Subject(s)
Osteoarthritis, Knee , Humans , Aged , Osteoarthritis, Knee/drug therapy , Collagen Type II , Treatment Outcome , Pain , Inflammation
11.
Pharmacol Biochem Behav ; 225: 173558, 2023 04.
Article in English | MEDLINE | ID: mdl-37088449

ABSTRACT

There are a few studies suggesting that the hippocampus is involved in the regulation of impulsivity, and which attempt to explain drug seeking behavior in addiction. In addition, cannabinoid receptor 1 (CB1R) is highly expressed in the hippocampus (HPP). To further understand the potential role of the hippocampal CB1R in impulsive and drug seeking behaviors, we characterized impulsivity in adolescent and adult male rats, by means of a delay discounting task (DDT) by evaluating preference and seeking motivation for alcohol (10 % v/v) consumption, and analyzing CB1R expression in CA1, CA3 and the dentate gyrus (DG) of the HPP as well as in the medial prefrontal cortex (mPFC). Our results show that adolescent rats display more impulsive choices than adult rats in the DDT. The k value is statistically higher in adolescents, further supporting that they are more impulsive. Besides, adolescent rats have higher forced and voluntary alcohol consumption and display a higher alcohol conditioned place preference (CPP) vs. adult rats. In addition, CB1R expression in CA3 and the DG is higher in adolescent vs. adult rats. Our data further support the role of the hippocampus in impulsivity with the potential involvement of the endocannabinoid system, considering that CB1R in CA3 and DG is higher in adolescents, who display impulsivity and alcohol seeking and consumption.


Subject(s)
Alcohol Drinking , Hippocampus , Impulsive Behavior , Animals , Male , Rats , Ethanol/metabolism , Hippocampus/metabolism , Motivation
12.
Acta ortop. mex ; 37(2): 85-93, mar.-abr. 2023. tab, graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1556737

ABSTRACT

Resumen: Introducción: evaluar los resultados radiográficos y funcionales obtenidos a largo plazo en pacientes adultos que presentaron no-consolidaciones atróficas diafisarias de húmero asociadas a osteoporosis; tratadas quirúrgicamente mediante reducción abierta y fijación interna con placas e injerto óseo. Material y métodos: evaluamos retrospectivamente 22 pacientes, con edad promedio de 72 años, el tiempo desde el trauma inicial hasta la cirugía definitiva promedió, 18 meses. Once pacientes eran fumadores y cuatro presentaban infección activa. El score de Constant y el DASH preoperatorios promediaron 23.13 y 81.04, respectivamente. El valor de la escala analógica del dolor preoperatorio promedió 7.45 puntos. Resultados: el seguimiento promedió 69 meses. Se obtuvo la consolidación en todos los casos, luego de un promedio de 4.68 meses. Al último seguimiento, los valores del DASH promediaron 20.27 puntos y el score de Constant promedió 79.31 puntos. La escala analógica del dolor promedió 0.77 puntos. La estabilización se realizó utilizando clavos placa bloqueados en 12 no-consolidaciones, placas bloqueadas de compresión en seis y doble placa en cuatro. Los pacientes con infección activa fueron tratados en dos etapas utilizando la técnica descripta por Masquelet. Se asoció injerto óseo en todas las reconstrucciones (autoinjerto esponjoso de cresta ilíaca en 17, aloinjerto en tres y se combinó aloinjerto estructural con autoinjerto esponjoso en dos). Dos gramos de vancomicina en polvo fueron asociados localmente al injerto óseo. Conclusión: la combinación de reducción abierta y fijación interna con placas e injerto óseo permitió obtener la consolidación y resultados funcionales objetivos y subjetivos buenos y predecibles a largo plazo en todos los casos, sin complicaciones mayores ni la necesidad de intervenciones quirúrgicas sucesivas.


Abstract: Introduction: to evaluate the long term radiographic and functional results achieved in adult patients with osteoporotic, atrophic, non-unions of the diaphyseal humerus, treated surgically by open reduction and internal fixation with plates and bone graft. Material and methods: we retrospectively evaluated 22 patients. Patient's age averaged 72 years. Time from initial trauma to definitive surgery averaged 18 months. Eleven patients were smokers, and four had active infection. Pre-operative Constant score and DASH score averaged 23.13 and 81.04, respectively. Pre-operative pain scale averaged 7.45 points. Results: follow-up averaged 69 months. Union was achieved in all cases after an average of 4.68 months. DASH score at last follow-up averaged 20.27 points and Constant score 79.31 points. Analog pain scale averaged 0.77 points. Stabilization was performed using locking blade plates in 12 non-unions, locking compression plates in six cases, and double plating in four non-unions. Patients with active infection were treated in two stages using Masquelet's technique. Bone graft was associated in all cases (cancellous iliac crest autograft in 17, allograft in three, and combined structural allograft and cancellous autograft in two). Two grams of vancomycin powder were associated to the bone graft in all cases. Conclusion: the use of open reduction and internal fixation with plates associated to bone graft with local antibiotics, aloud achieving bony union and good predictable long-term objective and subjective functional results in all cases, without major complications or the need of further surgical intervention.

13.
Mol Genet Genomics ; 298(2): 455-472, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36604348

ABSTRACT

The PumAB type-II toxin-antitoxin (TA) system is encoded by pumAB genes that are organized into an operon. This system is encoded by the pUM505 plasmid, isolated from a Pseudomonas aeruginosa clinical strain. The pumA gene encodes a putative RelE toxin protein (toxic component), whereas the pumB gene encodes a putative HTH antitoxin protein. The expression of the PumAB system in Escherichia coli confers plasmid stability. In addition, PumA toxin overexpression in P. aeruginosa possesses the capability to increase bacterial virulence, an effect that is neutralized by the PumB antitoxin. The aim of this study was to establish the mechanism of regulation of the PumAB toxin-antitoxin system from pUM505. By an in silico analysis of the putative regulatory elements, we identified two putative internal promoters, PpumB and PpumB-AlgU (in addition to the already reported PpumAB), located upstream of pumB. By RT-qPCR assays, we determined that the pumAB genes are transcribed differentially, in that the mRNA of pumB is more abundant than the pumA transcript. We also observed that pumB could be expressed individually and that its mRNA levels decreased under oxidative stress, during individual expression as well as co-expression of pumAB. However, under stressful conditions, the pumA mRNA levels were not affected. This suggests the negative regulation of pumB by stressful conditions. The PumB purified protein was found to bind to a DNA region located between the PpumAB and the pumA coding region, and PumA participates in PumB binding, suggesting that a PumA-PumB complex co-regulates the transcription of the pumAB operon. Interestingly, the pumA mRNA levels decreased after incubation in vitro with PumB protein. This effect was repressed by ribonuclease inhibitors, suggesting that PumB could function as an RNAse toward the mRNA of the toxin. Taken together, we conclude that the PumAB TA system possesses multiple mechanisms to regulate its expression, as well as that the PumB antitoxin generates a decrease in the mRNA toxin levels, suggesting an RNase function. Our analysis provides new insights into the understanding of the control of TA systems from mobile plasmid-encoded genes from a human pathogen.


Subject(s)
Antitoxins , Bacterial Toxins , Toxin-Antitoxin Systems , Humans , Antitoxins/genetics , Antitoxins/metabolism , Bacterial Toxins/genetics , Toxin-Antitoxin Systems/genetics , Apoptosis Regulatory Proteins/metabolism , Escherichia coli/genetics , Escherichia coli/metabolism , Endoribonucleases/genetics , Endoribonucleases/metabolism , RNA, Messenger , Ribonucleases/genetics , Ribonucleases/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Gene Expression Regulation, Bacterial
14.
Parasitol Res ; 122(2): 571-583, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36515752

ABSTRACT

We applied a step-down factor analysis (SDFA) and multi-site generalised dissimilarity modelling (MS-GDM) to local flea communities harboured by small mammals (i.e., collected at small sampling sites over a short time period) in two South American regions (Patagonia and the Northwestern Argentina) with the aim of understanding whether these communities were assembled via niche-based or dispersal-based processes. The SDFA allows us to determine whether clusters of flea assemblages across different types of climates, vegetation and soils can be distinguished (suggesting niche-based assembly). MS-GDM allows us to determine whether a substantial proportion of the variation in flea species turnover is explained by specific climate-associated, vegetation-associated and soil-associated variables (indicating niche-based assembly) or host turnover (indicating dispersal-based assembly). Mapping of assemblages on climate, vegetation and soil maps, according to their loadings on axis 1 or axis 2 of the SDFA, did not provide clear-cut results. Clusters of similar loadings could be recognized within some, but not other, climate, vegetation and soil types. However, MS-GDM demonstrated that the effect of environmental variables (especially air temperature) on flea compositional turnover was much stronger than that of host turnover, indicating the predominance of niche-based processes in local community assembly. A comparison of our results with those on the mechanisms that drive species assembly in regional communities allows us to conclude that local and regional communities result from the joint action of niche-based and dispersal-based processes, with the former more important at a smaller spatial scale and the latter at a larger spatial scale.


Subject(s)
Siphonaptera , Animals , Mammals , Soil , Tropical Climate , Argentina , Ecosystem , Biodiversity
16.
J Parasitol ; 108(6): 539-544, 2022 11 01.
Article in English | MEDLINE | ID: mdl-36374284

ABSTRACT

This is the first study to empirically evaluate the mortality of Amblyomma mixtum larvae caused by native entomopathogenic fungi (EPF) from cattle farm soils and the impact of the physicochemical conditions of those soils on the ability of EPF to kill ticks. The efficacy of 25 EPF strains isolated from cattle farms soils in Veracruz, Mexico, against A. mixtum ticks was evaluated using a larval immersion test. Physicochemical analyses of the soils where the EPF were isolated were carried out, and the results were correlated with the obtained mortality. The MaV25 strain showed a mortality of 36.55% (P < 0.05), followed by MaV57 with 27.30%, MaV08 with 26.21%, and MaV31 with 24.32% (P < 0.05). Nitrogen and potassium are nutritional components of soils that seem to be associated with mortality caused by the evaluated fungal strains. This is the first study in Mexico where the effect of EPF against A. mixtum is evaluated and also is the first study in the world that uses native strains from livestock soils against larvae of this tick. It is necessary to determine the virulence characteristics of EPF on A. mixtum to improve knowledge of fungus-tick interactions (Metarhizium anisopliae-A. mixtum).


Subject(s)
Beauveria , Ticks , Cattle , Animals , Farms , Amblyomma , Pest Control, Biological/methods , Mexico , Larva/microbiology , Soil
19.
Eur Rev Med Pharmacol Sci ; 26(2): 354-366, 2022 Jan.
Article in English | MEDLINE | ID: mdl-35113411

ABSTRACT

OBJECTIVE: The role that Beclin 1 (BECN1) plays in the development and progression of cancer mediated by autophagy, as well as its differential expression in breast cancer cell lines and mammary tumor tissue according to the molecular subtype, has been demonstrated. The objective of this study was to evaluate the association of BECN1 cytoplasmic expression with clinical and pathologic response, recurrence, disease-free survival (DFS) and overall survival (OS) in patients with locally advanced breast cancer (LABC), according to immunophenotype. PATIENTS AND METHODS: 64 patients with non-triple negative LABC and 20 patients with triple negative LABC who received preoperative chemotherapy were included in an observational, analytical and retrospective study to evaluate the cytoplasmic expression of BECN1 protein by immunohistochemistry in microarrays of breast cancer tissue obtained before treatment. Association between BECN1 and clinicopathological characteristics, clinical and pathologic response to preoperative chemotherapy and recurrence, were analyzed using Chi-square or Fisher's exact test. Postoperative DFS and OS were assessed by Kaplan-Meir curves, and the difference according to BECN1 expression was evaluated using the log-rank test. The bivariate analysis was performed using the Cox Proportional Hazards Model. A p-value of < 0.05 was considered statistically significant. RESULTS: BECN1 staining revealed positive expression in 62.5% of patients with non-triple negative and 60.0% with triple negative LABC. No association was observed between BECN1 expression and clinical or pathological response or recurrence. An association of the BECN1 expression with lower OS in triple negative breast cancer was found (HR = 5.19; 95% CI 1.12-24.02; p = 0.035). CONCLUSIONS: Results showed an association of the cytoplasmic expression of BECN1 with a lower OS, which could be a poor prognostic biomarker in triple negative LABC.


Subject(s)
Breast Neoplasms , Triple Negative Breast Neoplasms , Beclin-1 , Biomarkers, Tumor/analysis , Breast Neoplasms/pathology , Disease-Free Survival , Female , Humans , Prognosis , Retrospective Studies
20.
Sci Data ; 9(1): 57, 2022 02 16.
Article in English | MEDLINE | ID: mdl-35173163

ABSTRACT

The common vampire bat (Desmodus rotundus) is a sanguivorous (i.e., blood-eating) bat species distributed in the Americas from northern Mexico southwards to central Chile and Argentina. Desmodus rotundus is one of only three mammal species known to feed exclusively on blood, mainly from domestic mammals, although large wildlife and occasionally humans can also serve as a food source. Blood feeding makes D. rotundus an effective transmissor of pathogens to its prey. Consequently, this species is a common target of culling efforts by various individuals and organizations. Nevertheless, little is known about the historical distribution of D. rotundus. Detailed occurrence data are critical for the accurate assessment of past and current distributions of D. rotundus as part of ecological, biogeographical, and epidemiological research. This article presents a dataset of D. rotundus historical occurrence reports, including >39,000 locality reports across the Americas to facilitate the development of spatiotemporal studies of the species. Data are available at https://doi.org/10.6084/m9.figshare.15025296 .


Subject(s)
Chiroptera , Animals , Argentina , Humans , Mexico , United States
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