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1.
BMC Pediatr ; 24(1): 231, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561704

RESUMO

BACKGROUND: Effects of non-pharmaceutical interventions during the pandemic were mainly studied for severe outcomes. Among children, most of the burden of respiratory infections is related to infections which are not medically attended. The perspective on infections in the community setting is necessary to understand the effects of the pandemic on non-pharmaceutical interventions. METHODS: In the unique prospective LoewenKIDS cohort study, we compared the true monthly incidence of self-reported acute respiratory infections (ARI) in about 350 participants (aged 3-4 years old) between October 2019 to March 2020 (pre-pandemic period) and October 2020 to March 2021 (pandemic period). Parents reported children's symptoms using a diary. Parents were asked to take a nasal swab of their child during all respiratory symptoms. We analysed 718 swabs using Multiplex PCR for 25 common respiratory viruses and bacteria. RESULTS: During the pre-pandemic period, on average 44.6% (95% CI: 39.5-49.8%) of children acquired at least one ARI per month compared to 19.9% (95% CI: 11.1-28.7%) during the pandemic period (Incidence Rate Ratio = 0.47; 95% CI: 0.41-0.54). The detection of influenza virus decreased absolute by 96%, respiratory syncytial virus by 65%, metapneumovirus by 95%, parainfluenza virus by 100%, human enterovirus by 96% and human bocavirus by 70% when comparing the pre-pandemic to the pandemic period. However, rhinoviruses were nearly unaffected by NPI. Co-detection (detection of more than one virus in a single symptomatic swab) was common in the pre-pandemic period (222 of 390 samples with viral detection; 56.9%) and substantially less common during the pandemic period (46 of 216 samples; 21.3%). CONCLUSION: Non-pharmaceutical interventions strongly reduced the incidence of all respiratory infections in preschool children but did not affect rhinovirus.


Assuntos
COVID-19 , Metapneumovirus , Infecções Respiratórias , Humanos , Pré-Escolar , Lactente , Estudos de Coortes , Estudos Prospectivos , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/prevenção & controle , Rhinovirus
2.
J Exp Bot ; 73(10): 3251-3267, 2022 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-34791180

RESUMO

Drought stress causes crop yield losses worldwide. Sorghum is a C4 species tolerant to moderate drought stress, and its extensive natural variation for photosynthetic traits under water-limiting conditions can be exploited for developing cultivars with enhanced stress tolerance. The objective of this study was to discover genes/genomic regions that control the sorghum photosynthetic capacity under pre-anthesis water-limiting conditions. We performed a genome-wide association study for seven photosynthetic gas exchange and chlorophyll fluorescence traits during three periods of contrasting soil volumetric water content (VWC): control (30% VWC), drought (15% VWC), and recovery (30% VWC). Water stress was imposed with an automated irrigation system that generated a controlled dry-down period for all plants, to perform an unbiased genotypic comparison. A total of 60 genomic regions were associated with natural variation in one or more photosynthetic traits in a particular treatment or with derived variables. We identified 33 promising candidate genes with predicted functions related to stress signaling, oxidative stress protection, hormonal response to stress, and dehydration protection. Our results provide new knowledge about the natural variation and genetic control of sorghum photosynthetic response to drought with the ultimate goal of improving its adaptation and productivity under water stress scenarios.


Assuntos
Secas , Sorghum , Desidratação , Grão Comestível/genética , Estudo de Associação Genômica Ampla , Fotossíntese/genética , Sorghum/genética
3.
Exp Parasitol ; 238: 108261, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35460696

RESUMO

Toxoplasma gondii, as other apicomplexa, employs adhesins transmembrane proteins for binding and invasion to host cells. Search and characterization of adhesins is pivotal in understanding Apicomplexa invasion mechanisms and targeting new druggable candidates. This work developed a machine learning software called ApiPredictor UniQE V2.0, based on two approaches: support vector machines and multilayer perceptron, to predict adhesins proteins from amino acid sequences. By using ApiPredictor UniQE V2.0, five SAG-Related Sequences (SRSs) were identified within the Toxoplasma gondii proteome. One of those candidates, TgSRS12B, was cloned in plasmid pEXP5-CT/TOPO and expressed in E. coli BL21 DE3. The resulting recombinant protein was purified via affinity chromatography. Co-precipitation assays in CaCo and Muller cells showed interactions between TgSRS12B-His-tagged and the membrane fractions from both human cell lines. In conclusion, we demonstrated that ApiPredictor UniQE V2.0, a bioinformatic free software, was able to identify TgSRS12B as a new adhesin protein.


Assuntos
Toxoplasma , Escherichia coli/metabolismo , Humanos , Aprendizado de Máquina , Plasmídeos/genética , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Toxoplasma/genética , Toxoplasma/metabolismo
4.
Dig Dis ; 39(3): 294-300, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32810850

RESUMO

BACKGROUND: Probiotics and antispasmodics have been tested extensively in the management of symptoms of irritable bowel syndrome (IBS), but they have rarely been evaluated in combination. The objective of this pilot study was to assess the efficacy of treatment with the probiotic formulation i3.1 (Lactobacillus plantarum CECT7484 and CECT7485 and Pediococcus acidilactici CECT7483), with or without the addition of the antispasmodic alverine/simethicone, in improving IBS-related quality of life (QoL) and reducing abdominal pain and diarrhea in patients with IBS. METHODS: This was a randomized, placebo-controlled clinical trial with 3 parallel arms (probiotic, probiotic plus antispasmodic, and placebo). Patients with IBS (N = 55) were recruited at the Gastroenterology Department of the Juárez Hospital (México City). QoL was assessed with the IBS-QoL questionnaire, abdominal pain with a visual analog scale, and stool consistency with the Bristol scale. RESULTS: The IBS-QoL rate of response (ITT analysis) was 50.0% for patients in the group with probiotic alone, 68.4% in the group with probiotic plus antispasmodic, and 16.7% in the group with placebo after 6 weeks of treatment (p = 0.005). Response to abdominal pain was reported by 38.9% of patients treated with probiotic, 57.9% with probiotic plus antispasmodic, and 16.7% with placebo (p = 0.035). Regarding stool consistency, a response to treatment was reported by 44.4% of patients treated with probiotic, 57.9% with probiotic plus antispasmodic, and 16.7% with placebo (p = 0.032). CONCLUSION: The results are consistent with previous studies on the use of the i3.1 probiotic formulation for the management of symptoms in IBS patients, and the addition of an antispasmodic improves its observed effects.


Assuntos
Síndrome do Intestino Irritável/tratamento farmacológico , Parassimpatolíticos/uso terapêutico , Probióticos/uso terapêutico , Qualidade de Vida , Dor Abdominal/tratamento farmacológico , Adulto , Método Duplo-Cego , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Probióticos/administração & dosagem , Inquéritos e Questionários , Resultado do Tratamento
5.
BMC Vet Res ; 15(1): 23, 2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30630483

RESUMO

BACKGROUND: Bovine Viral Diarrhea Virus (BVDV) is associated with gastrointestinal, respiratory and reproductive diseases of livestock across the world that causes continuous economic losses in the cattle industry. This virus can establish a persistent infection (PI) in calves after the fetal infection, making BVDV positive catle carriers and primary reservoirs which will constantly transmit the virus to healthy and new-born animals. For this reason, the detection of the PI animals in herds is the first line of prevention of the viral infection. RESULTS: In this study, PI animals were detected in five different regions of Colombia through RT-PCR techniques and confirmed by sequencing. BVDV genotypes were determined using one fragment of the 5'UTR. It was found a 7% BVDV prevalence in animals and 22% in farms; and genotype 1 was identified as a single genotype for all of the samples. All samples were BVDV 1a. CONCLUSION: This is the first report in Colombia with higher prevalence rates compared with other places in the world, turned out to be of great importance for the ranchers, the vaccine producers and animal health control parties.


Assuntos
Doença das Mucosas por Vírus da Diarreia Viral Bovina/epidemiologia , Animais , Doença das Mucosas por Vírus da Diarreia Viral Bovina/prevenção & controle , Doença das Mucosas por Vírus da Diarreia Viral Bovina/virologia , Bovinos , Colômbia/epidemiologia , Vírus da Diarreia Viral Bovina/classificação , Feminino , Masculino , Filogenia , Prevalência , Reação em Cadeia da Polimerase em Tempo Real/veterinária
6.
Proc Natl Acad Sci U S A ; 112(47): 14734-9, 2015 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-26554020

RESUMO

The allocation of carbon and nitrogen resources to the synthesis of plant proteins, carbohydrates, and lipids is complex and under the control of many genes; much remains to be understood about this process. QQS (Qua-Quine Starch; At3g30720), an orphan gene unique to Arabidopsis thaliana, regulates metabolic processes affecting carbon and nitrogen partitioning among proteins and carbohydrates, modulating leaf and seed composition in Arabidopsis and soybean. Here the universality of QQS function in modulating carbon and nitrogen allocation is exemplified by a series of transgenic experiments. We show that ectopic expression of QQS increases soybean protein independent of the genetic background and original protein content of the cultivar. Furthermore, transgenic QQS expression increases the protein content of maize, a C4 species (a species that uses 4-carbon photosynthesis), and rice, a protein-poor agronomic crop, both highly divergent from Arabidopsis. We determine that QQS protein binds to the transcriptional regulator AtNF-YC4 (Arabidopsis nuclear factor Y, subunit C4). Overexpression of AtNF-YC4 in Arabidopsis mimics the QQS-overexpression phenotype, increasing protein and decreasing starch levels. NF-YC, a component of the NF-Y complex, is conserved across eukaryotes. The NF-YC4 homologs of soybean, rice, and maize also bind to QQS, which provides an explanation of how QQS can act in species where it does not occur endogenously. These findings are, to our knowledge, the first insight into the mechanism of action of QQS in modulating carbon and nitrogen allocation across species. They have major implications for the emergence and function of orphan genes, and identify a nontransgenic strategy for modulating protein levels in crop species, a trait of great agronomic significance.


Assuntos
Proteínas de Arabidopsis/metabolismo , Carbono/metabolismo , Genes de Plantas , Nitrogênio/metabolismo , Fatores de Transcrição/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Modelos Biológicos , Mutação , Oryza/genética , Fenótipo , Fotossíntese , Filogenia , Folhas de Planta/fisiologia , Plantas Geneticamente Modificadas , Ligação Proteica , Estrutura Terciária de Proteína , Glycine max/genética , Glycine max/crescimento & desenvolvimento , Especificidade da Espécie
7.
J Exp Bot ; 68(16): 4545-4557, 2017 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-28981780

RESUMO

Sorghum (Sorghum bicolor L. Moench) is a C4 species sensitive to the cold spring conditions that occur at northern latitudes, especially when coupled with excessive light, and that greatly affect the photosynthetic rate. The objective of this study was to discover genes/genomic regions that control the capacity to cope with excessive energy under low temperature conditions during the vegetative growth period. A genome-wide association study (GWAS) was conducted for seven photosynthetic gas exchange and chlorophyll fluorescence traits under three consecutive temperature treatments: control (28 °C/24 °C), cold (15 °C/15 °C), and recovery (28 °C/24 °C). Cold stress significantly reduced the rate of photosynthetic CO2 uptake of sorghum plants, and a total of 143 unique genomic regions were discovered associated with at least one trait in a particular treatment or with derived variables. Ten regions on chromosomes 3, 4, 6, 7, and 8 that harbor multiple significant markers in linkage disequilibrium (LD) were consistently identified in gas exchange and chlorophyll fluorescence traits. Several candidate genes within those intervals have predicted functions related to carotenoids, phytohormones, thioredoxin, components of PSI, and antioxidants. These regions represent the most promising results for future validation and with potential application for the improvement of crop productivity under cold stress.


Assuntos
Fotossíntese/genética , Sorghum/fisiologia , Clorofila/química , Clorofila/metabolismo , Temperatura Baixa , Resposta ao Choque Frio/genética , Variação Genética , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único , Sorghum/genética
8.
Cell Rep ; 43(5): 114153, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38687643

RESUMO

Gut-draining mesenteric and celiac lymph nodes (mLNs and celLNs) critically contribute to peripheral tolerance toward food and microbial antigens by supporting the de novo induction of regulatory T cells (Tregs). These tolerogenic properties of mLNs and celLNs are stably imprinted within stromal cells (SCs) by microbial signals and vitamin A (VA), respectively. Here, we report that a single, transient gastrointestinal infection in the neonatal, but not adult, period durably abrogates the efficient Treg-inducing capacity of celLNs by altering the subset composition and gene expression profile of celLNSCs. These cells carry information about the early-life pathogen encounter until adulthood and durably instruct migratory dendritic cells entering the celLN with reduced tolerogenic properties. Mechanistically, transiently reduced VA levels cause long-lasting celLN functional impairment, which can be rescued by early-life treatment with VA. Together, our data highlight the therapeutic potential of VA to prevent sequelae post gastrointestinal infections in infants.


Assuntos
Linfonodos , Linfócitos T Reguladores , Vitamina A , Animais , Linfonodos/imunologia , Linfonodos/patologia , Linfonodos/efeitos dos fármacos , Vitamina A/farmacologia , Vitamina A/uso terapêutico , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/efeitos dos fármacos , Camundongos , Animais Recém-Nascidos , Tolerância Imunológica/efeitos dos fármacos , Células Dendríticas/imunologia , Camundongos Endogâmicos C57BL , Feminino
9.
J Thorac Oncol ; 19(6): 941-953, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38159809

RESUMO

INTRODUCTION: Lenvatinib plus pembrolizumab was found to have antitumor activity and acceptable safety in previously treated metastatic NSCLC. We evaluated first-line lenvatinib plus pembrolizumab versus placebo plus pembrolizumab in metastatic NSCLC in the LEAP-007 study (NCT03829332/NCT04676412). METHODS: Patients with previously untreated stage IV NSCLC with programmed cell death-ligand 1 tumor proportion score of at least 1% without targetable EGFR/ROS1/ALK aberrations were randomized 1:1 to lenvatinib 20 mg or placebo once daily; all patients received pembrolizumab 200 mg every 3 weeks for up to 35 cycles. Primary end points were progression-free survival (PFS) per Response Evaluation Criteria in Solid Tumors version 1.1 and overall survival (OS). We report results from a prespecified nonbinding futility analysis of OS performed at the fourth independent data and safety monitoring committee review (futility bound: one-sided p < 0.4960). RESULTS: A total of 623 patients were randomized. At median follow-up of 15.9 months, median (95% confidence interval [CI]) OS was 14.1 (11.4‒19.0) months in the lenvatinib plus pembrolizumab group versus 16.4 (12.6‒20.6) months in the placebo plus pembrolizumab group (hazard ratio = 1.10 [95% CI: 0.87‒1.39], p = 0.79744 [futility criterion met]). Median (95% CI) PFS was 6.6 (6.1‒8.2) months versus 4.2 (4.1‒6.2) months, respectively (hazard ratio = 0.78 [95% CI: 0.64‒0.95]). Grade 3 to 5 treatment-related adverse events occurred in 57.9% of patients (179 of 309) versus 24.4% (76 of 312). Per data and safety monitoring committee recommendation, the study was unblinded and lenvatinib and placebo were discontinued. CONCLUSIONS: Lenvatinib plus pembrolizumab did not have a favorable benefit‒risk profile versus placebo plus pembrolizumab. Pembrolizumab monotherapy remains an approved treatment option in many regions for first-line metastatic NSCLC with programmed cell death-ligand 1 tumor proportion score of at least 1% without EGFR/ALK alterations.


Assuntos
Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Compostos de Fenilureia , Quinolinas , Humanos , Quinolinas/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Masculino , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Feminino , Método Duplo-Cego , Compostos de Fenilureia/uso terapêutico , Pessoa de Meia-Idade , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Adulto , Antígeno B7-H1/metabolismo , Antígeno B7-H1/antagonistas & inibidores , Idoso de 80 Anos ou mais
10.
Neurooncol Pract ; 10(4): 381-390, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37457227

RESUMO

Background: DICER1 alterations are associated with intracranial tumors in the pediatric population, including pineoblastoma, pituitary blastoma, and the recently described "primary DICER1-associated CNS sarcoma" (DCS). DCS is an extremely aggressive tumor with a distinct methylation signature and a high frequency of co-occurring mutations. However, little is known about its treatment approach and the genomic changes occurring after exposure to chemoradiotherapy. Methods: We collected clinical, histological, and molecular data from eight young adults with DCS. Genomic analysis was performed by Next-generation Sequencing (NGS). Subsequently, an additional germline variants analysis was completed. In addition, an NGS analysis on post-progression tumor tissue or liquid biopsy was performed when available. Multiple clinicopathological characteristics, treatment variables, and survival outcomes were assessed. Results: Median age was 20 years. Most lesions were supratentorial. Histology was classified as fusiform cell sarcomas (50%), undifferentiated (unclassified) sarcoma (37.5%), and chondrosarcoma (12.5%). Germline pathogenic DICER1 variants were present in two patients, 75% of cases had more than one somatic alteration in DICER1, and the most frequent commutation was TP53. Seven patients were treated with surgery, Ifosfamide, Cisplatin, and Etoposide (ICE) chemotherapy and radiotherapy. The objective response was 75%, and the median time to progression (TTP) was 14.5 months. At progression, the most common mutations were in KRAS and NF1. Overall survival was 30.8 months. Conclusions: DCS is an aggressive tumor with limited therapeutic options that requires a comprehensive diagnostic approach, including molecular characterization. Most cases had mutations in TP53, NF1, and PTEN, and most alterations at progression were related to MAPK, RAS and PI3K signaling pathways.

11.
Integr Comp Biol ; 62(4): 1061-1075, 2022 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-35595471

RESUMO

Openly shared low-cost electronic hardware applications, known as open electronics, have sparked a new open-source movement, with much untapped potential to advance scientific research. Initially designed to appeal to electronic hobbyists, open electronics have formed a global "maker" community and are increasingly used in science and industry. In this perspective article, we review the current costs and benefits of open electronics for use in scientific research ranging from the experimental to the theoretical sciences. We discuss how user-made electronic applications can help (I) individual researchers, by increasing the customization, efficiency, and scalability of experiments, while improving data quantity and quality; (II) scientific institutions, by improving access to customizable high-end technologies, sustainability, visibility, and interdisciplinary collaboration potential; and (III) the scientific community, by improving transparency and reproducibility, helping decouple research capacity from funding, increasing innovation, and improving collaboration potential among researchers and the public. We further discuss how current barriers like poor awareness, knowledge access, and time investments can be resolved by increased documentation and collaboration, and provide guidelines for academics to enter this emerging field. We highlight that open electronics are a promising and powerful tool to help scientific research to become more innovative and reproducible and offer a key practical solution to improve democratic access to science.


Assuntos
Eletrônica , Pesquisadores , Animais , Humanos , Reprodutibilidade dos Testes
12.
Sci Rep ; 12(1): 18125, 2022 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-36302806

RESUMO

DRIS (Diagnosis Recommendation Integrated System) is a tool used in the interpretation of leaf analyses that values the balance of nutrients, an important fact for a better assessment of the nutritional status of banana plants. Its usefulness depends on the ability to identify the nutrients that limit productivity in order to correct possible nutritional imbalances, but there is a lack of research in all crops, including bananas, to assess the accuracy of these diagnoses, which have a worrying global implication. To this end, this study evaluates DRIS norms for banana cultivation in Ecuador and the use of accuracy measurements for nutritional diagnosis, verifying the capacity of DRIS to detect true nutritional status based on plant response. The database created here contains 233 results referring to productivity and leaf contents of N, P, K, Ca, Mg, S, Cl, Fe, Mn, Cu, B, and Zn for banana trees in 2018, 2019, and 2020. Then, a field experiment evaluated doses of nitrogen and potassium and the accuracy of DRIS norms for N and K. The results show that the DRIS of banana produced in Ecuador depends on the nutrient being variable according to the crop nutritional status. The DRIS norms for diagnosis of N and K result in an acceptable accuracy to identify only deficiencies and toxicities, respectively, indicating the need for adjustments in these standards for later use in the field. Thus, there is a need for more research aiming to adopt calibrated DRIS diagnostic norms to assess the nutritional status of bananas in Ecuador.


Assuntos
Musa , Nitrogênio , Potássio , Produtos Agrícolas , Folhas de Planta
13.
Lancet Reg Health Am ; 7: 100131, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36777652

RESUMO

Background: Hypophosphatemic rickets is a rare, genetic syndrome with multisystem involvement. It causes skeletal abnormalities, painful enthesopathies, increased risk of fracture, and short stature; leading to a substantial burden of disease, disability, and worsening of quality of life. To improve health conditions of people living with this disease, it is essential to know its prevalence which is currently unknown in Colombia. This study aimed to estimate the prevalence of hypophosphatemic rickets in Colombia by using a mathematical model and national statistic records. Methods: We executed a model to estimate probabilities of transitions between health, disease, and death states (Markov chains). The model was fed with international prevalences taken from original studies (systematic review) and administrative records' data from SISPRO (a national health information system) using the International Classification of Diseases (ICD-10) E833 code, vital statistics, and census data. World Health Organization's (WHO) DISMOD II software was used to develop the model. Findings: The estimated overall prevalence of hypophosphatemic rickets in Colombia in 2018 was 2·03 cases per 100 000 people (981 affected people), with a sensitive range of 1·97 to 2·09. The estimated prevalence by sex was 2·61 (645 people) and 1·43 (336 people) cases per 100 000 women and men, respectively. Interpretation: Our overall estimated prevalence shows consistency with original international data. This is the first prevalence estimation of hypophosphatemic rickets in Colombia and will be relevant to support public health decisions for rare diseases and to provide a pre-test probability framework in clinical practice. DISMOD II and the model are useful tools to estimate the prevalence of rare and orphan diseases, when probabilistic studies cannot be carried out. There are limited bibliographic resources worldwide reporting prevalence values supported by original studies. Our study can be used as a cost-effective methodology reference in this regard, especially for Latin America. Funding: Ultragenyx Pharmaceutical, as a donation.

14.
Vet Parasitol Reg Stud Reports ; 22: 100487, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33308760

RESUMO

Fasciola hepatica is a trematode parasite with a worldwide distribution that affects mammals, including humans, and is considered a major food safety and public health problem. A research was conducted in three hundred eighty-five livestock farms located in different altitudinal regions of Colombia between February 2017 and March 2018 with the aim to determine the coprological prevalence, seroprevalence (SP) and risk factors associated with liver fluke F. hepatica. A total of 5620 fecal sample were collected from cattle and processed using sedimentation technique. Additionally, 597 blood samples were collected and processed by an ELISA test. The coprological prevalence of F. hepatica in animals and herds was 6.4% and 38.4%, respectively. Regarding the prevalence by municipalities, there was statistical association (P < .05), indicating that the prevalence was higher in those municipalities above 2000 masl (meters above sea level). Regarding risk factors, cattle raised in municipalities at 2000 to 3000 masl showed about 4 (OR = 3.96 [CI95% 3.1-5]; P < .05) times higher probability for infection than those raised at lower altitude. Cattle from 2 to 3 year of age, showed almost 4 times (OR = 3.7[CI95% 2.5-5.4]; P < .05), increased infection risk. Females and dairy breeds showed almost 2 (OR = 1.9 [CI95% 1.3-2.6]; P < .05) and 10 times (OR = 10 [CI95% 7.8-12.8]; P < .05), respectively, increased infection risk. The presence of antibodies anti- F. hepatica (SP = 37.8%; [CI95% 35.8-39.7]; P < .05) in cattle of the region under study is confirmed, which suggests an endemic behavior of this parasitosis. The present study provides current information on the prevalence of F. hepatica in different altitudinal regions of Colombia, and these findings could be useful for designing new holistic control measures for the liver fluke F. hepatica infection.


Assuntos
Doenças dos Bovinos , Bovinos/parasitologia , Fasciola hepatica , Fasciolíase/veterinária , Altitude , Animais , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Colômbia/epidemiologia , Fasciolíase/epidemiologia , Feminino , Prevalência , Fatores de Risco , Estudos Soroepidemiológicos
15.
Chemosphere ; 253: 126637, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32278910

RESUMO

A kinetic study was carried out in a sequencing batch reactor (SBR) (125 mg NH4+-N/L) inoculated with a physiologically stable nitrifying sludge not previously acclimated to sulfur compounds and fed at different initial sulfide concentrations (2.5-20.0 mg HS--S/L). Up to 10.0 mg HS--S/L, the nitrifying process kept stable and complete, reaching an ammonium consumption efficiency (ENH4+) of 100% and a nitrate yield (YNO3-) of 0.95 ± 0.03 mg NO3--N/mg NH4+-N consumed. At 15.0 and 20.0 mg HS--S/L, after an initial alteration in the nitrite oxidizing process, the YNO2- was decreasing throughout the cycles and the YNO3- increasing, obtaining in the last cycle at 20.0 mg HS--S/L, an ENH4+ of 100%, a YNO2- of zero, and a YNO3- of 0.80 mg NO3--N/mg NH4+-N consumed. At the end of the period at 20.0 mg HS--S/L, the specific rates of ammonium consumption and nitrate formation were 15 and 55% lower than their respective values in the control period without sulfide addition, showing that the sludge had a better metabolic adaptation for ammonium oxidizing activity than for nitrite oxidizing activity. The sludge acquired a higher sulfide oxidation capacity along the cycles. Bacterial population dynamics assessment indicated that the ammonium oxidizing bacteria (AOB) community was more diverse and stable than the nitrite oxidizing bacteria (NOB) community. The use of consortia with a previously stabilized nitrifying activity in SBR may constitute an alternative for eliminating simultaneously ammonium by nitrification and sulfide by sulfide oxidation and be implemented for the treatment of wastewater with ammonium and sulfide.


Assuntos
Compostos de Amônio/metabolismo , Sulfetos/metabolismo , Eliminação de Resíduos Líquidos/métodos , Bactérias/metabolismo , Reatores Biológicos/microbiologia , Cinética , Nitratos/metabolismo , Nitrificação , Nitritos/metabolismo , Oxirredução , Dinâmica Populacional , Esgotos/microbiologia , Compostos de Enxofre/metabolismo , Águas Residuárias
16.
Infect Genet Evol ; 80: 104171, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31904555

RESUMO

Bovine leukemia virus (BLV) is one of the five agents considered most significant for cattle. It is important to determine the prevalence and molecular epidemiology of BLV throughout the country in order to gain a more thorough understanding of the current situation of BLV and to reveal the possibility of masked genotypes that the primers used by OIE are unable to identify. Blood samples were collected at random from 289 cows distributed in 75 farms across the country. PCR amplification of env, gag and tax gene segments was performed. The obtained amplicons were sequenced and then subjected to phylogenetic analyses. A total of 62% of the cows present at 92% of the farms were BLV-positive for gag fragment. Genotype 1 was exclusively detected by env gene segment when analyzed using previously reported primers. However, tax gene analysis revealed circulation of genotype 6 variants, which were also detected based on env gene analysis with newly designed primers. These results indicate that current genotyping approaches based on partial env sequencing may bias BLV genetic variability approaches and underestimate the diversity of the detected BLV genotypes. This report is one of the first molecular and epidemiological studies of BLV conducted in Colombia, which contributes to the global epidemiology of the virus; it also highlights the substantial impact of BLV on the country's livestock and thus is a useful resource for farmers and government entities.


Assuntos
Leucose Enzoótica Bovina/epidemiologia , Leucose Enzoótica Bovina/virologia , Vírus da Leucemia Bovina/classificação , Vírus da Leucemia Bovina/genética , Animais , Bovinos , Colômbia/epidemiologia , Genes Virais , Variação Genética , Genótipo , Geografia Médica , Epidemiologia Molecular , Filogenia , Filogeografia , Reação em Cadeia da Polimerase/métodos , Reação em Cadeia da Polimerase/normas , Prevalência , Vigilância em Saúde Pública
17.
J Phys Chem B ; 113(40): 13208-15, 2009 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-19754092

RESUMO

The all electron full potential linearized augmented plane wave method has been used for an ab initio theoretical study of the band structure, density of states and electron charge density, and the spectral features of the linear and nonlinear optical susceptibilities for the host CuSn and Li(2)CuSn compounds. We have calculated the density of states at Fermi energy and the electronic specific heat coefficient (gamma). The total charge densities in the (100) and (110) planes were calculated. We noticed that inserting Li into CuSn leads to give two structures in the spectral features of the linear optical susceptibilities while the host compound gives only one structure. Insertion of Li into CuSn leads to breaking the symmetry resulting in noncentrosymmetric material. We have calculated the complex second-order nonlinear optical susceptibility tensor for the intercalated compound.


Assuntos
Simulação por Computador , Cobre/química , Fontes de Energia Elétrica , Eletrodos , Lítio/química , Estanho/química , Manufaturas , Modelos Químicos , Óptica e Fotônica
18.
Vet World ; 12(7): 951-958, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31528017

RESUMO

AIM: The research was conducted to determine the seroprevalence and risk factor associated with respiratory viral pathogens in dual-purpose cattle of Aguachica, Rio de Oro and La Gloria municipalities in Cesar department, Colombia. MATERIALS AND METHODS: The seroprevalence study was done from the random sampling (n=1000) of blood collected from 29 dual-purpose herds, located in three municipalities (Aguachica, Rio de Oro, and La Gloria) of Cesar department. The presence of antibodies against bovine herpesvirus type 1 (BHV-1), bovine respiratory syncytial virus (BRSV), bovine viral diarrhea virus (BVDV), and bovine parainfluenza-3 virus (BPI-3V) in the samples was detected by indirect enzyme-linked immunosorbent assay. Epidemiological data were obtained using a questionnaire administered to the owner or manager of each herd. RESULTS: The overall highest seroprevalence was observed for BHV-1 (94.7%), followed by BRSV (98.6%), BVDV (35.2%), and BPI-3V (47.1%). Regarding the seroprevalence by municipalities, there was a statistical association (p<0.05) for BVDV; however, for BRSV, BHV-1, and BPI-3V, no statistical association was found (p>0.05) between seropositive values and the municipalities, indicating that animal was seropositive in similar proportions in the three municipalities. Female sex and older animals (>24 months) were a significant risk factor for BHV-1 and BPI-3V infection. Regarding the clinical signs, there was a statistical association (p<0.05) between the seropositive values of BVDV and most of clinical signs observed, except for abortion. CONCLUSION: This research confirms the high seroprevalence of the respiratory viral pathogens in nonvaccinated cattle within the study areas. Therefore, appropriate sanitary management practices and routine vaccination programs should be adopted to reduce the seroprevalence of these infectious agents.

19.
PLoS One ; 13(6): e0198546, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29870560

RESUMO

The development of high-yielding crops with drought tolerance is necessary to increase food, feed, fiber and fuel production. Methods that create similar environmental conditions for a large number of genotypes are essential to investigate plant responses to drought in gene discovery studies. Modern facilities that control water availability for each plant remain cost-prohibited to some sections of the research community. We present an alternative cost-effective automated irrigation system scalable for a high-throughput and controlled dry-down treatment of plants. This system was tested in sorghum using two experiments. First, four genotypes were subjected to ten days of dry-down to achieve three final Volumetric Water Content (VWC) levels: drought (0.10 and 0.20 m3 m-3) and control (0.30 m3 m-3). The final average VWC was 0.11, 0.22, and 0.31 m3 m-3, respectively, and significant differences in biomass accumulation were observed between control and drought treatments. Second, 42 diverse sorghum genotypes were subjected to a seven-day dry-down treatment for a final drought stress of 0.15 m3 m-3 VWC. The final average VWC was 0.17 m3 m-3, and plants presented significant differences in photosynthetic rate during the drought period. These results demonstrate that cost-effective automation systems can successfully control substrate water content for each plant, to accurately compare their phenotypic responses to drought, and be scaled up for high-throughput phenotyping studies.


Assuntos
Irrigação Agrícola/economia , Produtos Agrícolas/genética , Genoma de Planta/genética , Sorghum/fisiologia , Estresse Fisiológico , Irrigação Agrícola/instrumentação , Irrigação Agrícola/métodos , Análise Custo-Benefício , Secas , Regulação da Expressão Gênica de Plantas/fisiologia , Genótipo , Técnicas de Genotipagem/economia , Técnicas de Genotipagem/instrumentação , Técnicas de Genotipagem/métodos , Fotossíntese/genética , Reprodutibilidade dos Testes , Sorghum/genética
20.
Vet Parasitol Reg Stud Reports ; 12: 26-30, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-31014803

RESUMO

Gastrointestinal parasites are one of the most important health problems in cattle worldwide, as they cause economic losses in the herds. Twenty - seven double purpose herds were visited to determine the prevalence of gastrointestinal parasites in cattle at the Rio de Oro and Aguachica municipalities. Overall, 862 fecal samples were collected in three age groups: <12months, 12-24months and >24months. Stool samples were taken directly from the rectum and refrigerated until processing. For parasite determination, fecal samples were processed using coprological techniques. The parasitic genera were identified by egg or infective larval morphology. The global prevalence of gastrointestinal parasites was 83.2%, being the highest values for Eimeria sp. (77.9%), Strongyloides sp. (10.8%) and Haemonchus sp. (8.5%). Regarding the prevalence by municipalities, there was no statistical association (P>0.05) indicating that the prevalence was similar in the two municipalities. Regarding the results for Eimeria sp., different degrees of positivity were observed, reflecting that there was statistical association (P<0.05) with respect to the age group, suggesting that adult animals may act as infection source for calves. Likewise, there was statistical association (P<0.05) between the prevalence for Strongyloides sp., Haemonchus sp. and Trichostrongylus sp. with respect to the age group. It is concluded that there is a high prevalence of gastrointestinal parasites in dual-purpose cattle in the municipalities under study, and that it could be controlled by improving the hygienic conditions of the herds, and informing the farmer about parasite control programs.


Assuntos
Doenças dos Bovinos/epidemiologia , Trato Gastrointestinal/parasitologia , Helmintos/isolamento & purificação , Enteropatias Parasitárias/veterinária , Fatores Etários , Animais , Bovinos/parasitologia , Colômbia/epidemiologia , Fezes/parasitologia , Helmintíase Animal/epidemiologia , Helmintos/classificação , Enteropatias Parasitárias/epidemiologia , Contagem de Ovos de Parasitas , Prevalência
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