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1.
Sci Total Environ ; 927: 171917, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38580127

RESUMO

Lasiodiplodia hormozganensis, initially recognized as a fungal plant pathogen, is recognized now acknowledged as a potential threat to humans. However, our understanding of the pathogenesis mechanisms of Lasiodiplodia species remains limited, and the impact of temperature on its pathogenicity is unclear. This study aims to elucidate the effects of temperature on the biology of L. hormozganensis, focusing on the expression of pathogenesis-related molecules and its ability to function as a cross-kingdom pathogen. We conducted experiments at two different temperatures, 25 and 37 °C, analyzing the proteome and transcriptome of L. hormozganensis. Using strain CBS339.90, initially identified as L. theobromae but confirmed through ITS and tef1-α sequence analysis to be L. hormozganensis, we aimed to understand the fungus's protein expression under varying temperature conditions. Results from the functional analysis of the secretome at 25 °C showed a noteworthy presence of proteins related to carbohydrate metabolism, catabolism, plant cell wall degradation, and pathogenesis. However, when grown at 37 °C, the fungus exhibited an increased production of stress response and pathogenesis-related proteins. Our findings identified various pathways crucial for pathogenesis in both plants and humans, suggesting that L. hormozganensis possesses the genetic foundation to infect both hosts. Specific pathogenesis-related proteins, including the phytotoxin snodprot1, aspartic protease aspergillopepsin, and virulence protein SSD1, were also identified. Concluding, we propose a possible mechanism of how L. hormozganensis adapts to different temperatures. The shift in temperature results in the expression of genes that favor human related pathogenesis molecules.


Assuntos
Ascomicetos , Temperatura , Ascomicetos/fisiologia , Ascomicetos/genética , Doenças das Plantas/microbiologia , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Transcriptoma
2.
J Dairy Sci ; 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38460875

RESUMO

Cattle lameness remains a significant concern, causing economic losses and compromising animal welfare. Claw horn lesions have been identified as a major cause of lameness in dairy cows but its correlation with high-energy diet and ruminal acidosis remains unclear. Hence, the primary objective of this study was to assess the effects of a high starch and a conventional diet on the rumen environment, acute phase proteins, and metabolic alterations, with a particular focus on insulin resistance and the consequent implications for the histology of the hooves in Holstein steers. Sixteen animals were divided into the high-starch (HS; 37% starch) and conventional (CON; 16.8% starch) groups. Glucose tolerance tests (GTT), blood, rumen fluid analysis, and histological evaluations of the hoof tissue were conducted over a 102-d experimental period. The HS group showed a lower ruminal pH than the CON group, and with values indicating subacute ruminal acidosis (SARA). The plasma glucose and IGF-1 concentrations were higher in the HS group, suggesting an anabolic state. Both groups exhibited an increase in the insulin area under the curve (AUC) after the GTT on d 102. Histological analysis of the hooves showed a reduction in the length and width of the epidermal lamella in both groups. There was a significant negative correlation between the insulin AUC and the length and width of the epidermal lamella. Since both groups were similarly affected, the hypothesis that histological alterations were caused by the experimental diets still needs confirmation. Additionally, the development of SARA was not essential for the observed histological changes in the hoof. Further studies are warranted to thoroughly investigate the role of insulin and IGF-1 imbalances in claw health.

3.
Microb Genom ; 10(2)2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38376388

RESUMO

Accurate reconstruction of Escherichia coli antibiotic resistance gene (ARG) plasmids from Illumina sequencing data has proven to be a challenge with current bioinformatic tools. In this work, we present an improved method to reconstruct E. coli plasmids using short reads. We developed plasmidEC, an ensemble classifier that identifies plasmid-derived contigs by combining the output of three different binary classification tools. We showed that plasmidEC is especially suited to classify contigs derived from ARG plasmids with a high recall of 0.941. Additionally, we optimized gplas, a graph-based tool that bins plasmid-predicted contigs into distinct plasmid predictions. Gplas2 is more effective at recovering plasmids with large sequencing coverage variations and can be combined with the output of any binary classifier. The combination of plasmidEC with gplas2 showed a high completeness (median=0.818) and F1-Score (median=0.812) when reconstructing ARG plasmids and exceeded the binning capacity of the reference-based method MOB-suite. In the absence of long-read data, our method offers an excellent alternative to reconstruct ARG plasmids in E. coli.


Assuntos
Escherichia coli , Sequenciamento de Nucleotídeos em Larga Escala , Escherichia coli/genética , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos , Plasmídeos/genética
4.
PeerJ ; 12: e16695, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38188174

RESUMO

Antimicrobial resistance genes (ARG) are commonly found on acquired mobile genetic elements (MGEs) such as plasmids or transposons. Understanding the spread of resistance genes associated with mobile elements (mARGs) across different hosts and environments requires linking ARGs to the existing mobile reservoir within bacterial communities. However, reconstructing mARGs in metagenomic data from diverse ecosystems poses computational challenges, including genome fragment reconstruction (assembly), high-throughput annotation of MGEs, and identification of their association with ARGs. Recently, several bioinformatics tools have been developed to identify assembled fragments of plasmids, phages, and insertion sequence (IS) elements in metagenomic data. These methods can help in understanding the dissemination of mARGs. To streamline the process of identifying mARGs in multiple samples, we combined these tools in an automated high-throughput open-source pipeline, MetaMobilePicker, that identifies ARGs associated with plasmids, IS elements and phages, starting from short metagenomic sequencing reads. This pipeline was used to identify these three elements on a simplified simulated metagenome dataset, comprising whole genome sequences from seven clinically relevant bacterial species containing 55 ARGs, nine plasmids and five phages. The results demonstrated moderate precision for the identification of plasmids (0.57) and phages (0.71), and moderate sensitivity of identification of IS elements (0.58) and ARGs (0.70). In this study, we aim to assess the main causes of this moderate performance of the MGE prediction tools in a comprehensive manner. We conducted a systematic benchmark, considering metagenomic read coverage, contig length cutoffs and investigating the performance of the classification algorithms. Our analysis revealed that the metagenomic assembly process is the primary bottleneck when linking ARGs to identified MGEs in short-read metagenomics sequencing experiments rather than ARGs and MGEs identification by the different tools.


Assuntos
Bacteriófagos , Metagenoma , Metagenoma/genética , Elementos de DNA Transponíveis/genética , Ecossistema , Algoritmos , Bacteriófagos/genética
5.
Antibiotics (Basel) ; 12(5)2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37237829

RESUMO

The most common resistance mechanism to carbapenems is the production of carbapenemases. In 2021, the Pan American Health Organization warned of the emergence and increase in new carbapenemase combinations in Enterobacterales in Latin America. In this study, we characterized four Klebsiella pneumoniae isolates harboring blaKPC and blaNDM from an outbreak during the COVID-19 pandemic in a Brazilian hospital. We assessed their plasmids' transference ability, fitness effects, and relative copy number in different hosts. The K. pneumoniae BHKPC93 and BHKPC104 strains were selected for whole genome sequencing (WGS) based on their pulsed-field gel electrophoresis profile. The WGS revealed that both isolates belong to ST11, and 20 resistance genes were identified in each isolate, including blaKPC-2 and blaNDM-1. The blaKPC gene was present on a ~56 Kbp IncN plasmid and the blaNDM-1 gene on a ~102 Kbp IncC plasmid, along with five other resistance genes. Although the blaNDM plasmid contained genes for conjugational transfer, only the blaKPC plasmid conjugated to E. coli J53, without apparent fitness effects. The minimum inhibitory concentrations (MICs) of meropenem/imipenem against BHKPC93 and BHKPC104 were 128/64 and 256/128 mg/L, respectively. Although the meropenem and imipenem MICs against E. coli J53 transconjugants carrying the blaKPC gene were 2 mg/L, this was a substantial increment in the MIC relative to the original J53 strain. The blaKPC plasmid copy number was higher in K. pneumoniae BHKPC93 and BHKPC104 than in E. coli and higher than that of the blaNDM plasmids. In conclusion, two ST11 K. pneumoniae isolates that were part of a hospital outbreak co-harbored blaKPC-2 and blaNDM-1. The blaKPC-harboring IncN plasmid has been circulating in this hospital since at least 2015, and its high copy number might have contributed to the conjugative transfer of this particular plasmid to an E. coli host. The observation that the blaKPC-containing plasmid had a lower copy number in this E. coli strain may explain why this plasmid did not confer phenotypic resistance against meropenem and imipenem.

6.
Rev. med. Chile ; 150(10): 1401-1406, oct. 2022. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-1431842

RESUMO

Sulfhemoglobin (SulfHb) is formed by hemoglobin (Hb) oxidation by sulfur compounds. Sulfhemoglobinemia is mainly associated with drugs or intestinal bacterial overgrowth. Patients present with central cyanosis, an abnormal pulse oximetry and normal arterial oxygen partial pressure. These features are shared with methemoglobinemia (MetHb) whose diagnosis requires an arterial co-oximetry. Depending on the device used, SulfHb may produce interference with this technique. We report two females aged 31 and 43 years, consulting at the emergency room with cyanosis. Both had a history of acute and chronic, high dose zopiclone ingestion. Pulse oximetry showed desaturation but with normal arterial oxygen partial pressure. Cardiac and pulmonary diseases were ruled out. Co-oximetry in two different analyzers showed interference or normal MetHb percentages. No other complications ensued, and cyanosis decreased over days. Since MetHb was discarded among other causes of cyanosis in a compatible clinical context, the diagnosis of sulfhemoglobinemia was made. The confirmatory method is not available in Chile. The presence of SulfHb is difficult to diagnose, confirmatory tests are not readily available, and it frequently interferes with arterial co-oximetry. This is attributed to a similar absorbance peak of both pigments in arterial blood. Venous co-oximetry can be useful in this context. SulfHb is a self-limited condition in most cases, however it must be differentiated from methemoglobinemia to avoid inappropriate treatments like methylene blue.


Assuntos
Humanos , Feminino , Sulfemoglobinemia/complicações , Metemoglobinemia/diagnóstico , Metemoglobinemia/induzido quimicamente , Oxigênio , Oximetria/efeitos adversos , Cianose/complicações
7.
Artigo em Espanhol | LILACS | ID: biblio-1392317

RESUMO

En todo el mundo se han descrito efectos negativos de la pandemia de COVID-19 en la salud mental, especialmente en la población infanto-juvenil. Sin embargo, en Chile, la investigación disponible aún no se ha sistematizado. El objetivo de este estudio fue revisar sistemáticamente las publicaciones científicas sobre salud mental infanto-juvenil en Chile durante la pandemia de COVID-19. Se buscaron reportes de investigación en las bases de datos WoS, Scopus, SciELO y LILACS. Se incluyeron 13 estudios que cumplieron los criterios de inclusión. Los estudios son heterogéneos en cuanto a sus objetivos e instrumentos utilizados. Varios estudios coinciden en que hay un aumento de los síntomas internalizantes, externalizantes y somáticos en la población infanto-juvenil desde la pandemia. Es necesario promover investigaciones colaborativas y longitudinales e investigaciones que evalúen la eficacia de intervenciones preventivas y terapéuticas. Estos resultados pueden ser útiles para clínicos, académicos y tomadores de decisión en políticas públicas para que puedan adoptar medidas para mejorar la salud mental de esta población. Palabras Clave: Salud mental, niños, adolescentes, jóvenes, COVID-19.


Abstract. Negative effects of the COVID-19 pandemic on mental health have been described worldwide, especially in the child and youth population. However, in Chile, the available research has not yet been systematized. This study aimed to systematically review scientific publications on child and youth mental health in Chile during the COVID-19 pandemic. The WoS, Scopus, SciELO, and LILACS databases were searched for research reports. Thirteen studies that met the inclusion criteria were included. The studies are heterogeneous in terms of their objectives and instruments used. Several studies agree that there is an increase in internalizing, externalizing, and somatic symptoms in the child and youth population since the pandemic. There is a need to promote collaborative and longitudinal research, and research that evaluates the efficacy of preventive and therapeutic interventions. These results may be useful to clinicians, academics, and public policymakers so that they can take steps to improve the mental health of this population. Keywords: Mental health, children, adolescents, youth, COVID-19.


Assuntos
Humanos , Criança , Adolescente , Saúde Mental , COVID-19/psicologia , Pandemias
8.
Heliyon ; 8(3): e09028, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35342833

RESUMO

Pollution by polymeric materials - in particular plastics - has a negative effect on the health of our planet. Approximately 4.9 billion tons of plastic are estimated to have been improperly disposed of, with the environment as their final destination. This scenario comes from a linear economic system, extraction-production-consumption and finally disposal. The alarming panorama has created the need to find technological solutions that generate new uses for discarded polymeric materials or turn them into part of the production process to produce new and novel materials, such as carbon nanotubes, graphene, or other carbonaceous materials of high added value, modifying the economy for a circular and sustainable production model. This review highlights the negative impact that the disposal of plastic materials has on the environment and the research needs that allow solving the pollution problems generated in the environment by these wastes. Also, the review highlights the current and future directions of recovery plastic waste research-based to promote innovations in the plastic production sector that could allow obtaining breakpoints in other industrial sectors with the technology-based companies.

9.
Rev Med Chil ; 150(10): 1401-1406, 2022 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-37358100

RESUMO

Sulfhemoglobin (SulfHb) is formed by hemoglobin (Hb) oxidation by sulfur compounds. Sulfhemoglobinemia is mainly associated with drugs or intestinal bacterial overgrowth. Patients present with central cyanosis, an abnormal pulse oximetry and normal arterial oxygen partial pressure. These features are shared with methemoglobinemia (MetHb) whose diagnosis requires an arterial co-oximetry. Depending on the device used, SulfHb may produce interference with this technique. We report two females aged 31 and 43 years, consulting at the emergency room with cyanosis. Both had a history of acute and chronic, high dose zopiclone ingestion. Pulse oximetry showed desaturation but with normal arterial oxygen partial pressure. Cardiac and pulmonary diseases were ruled out. Co-oximetry in two different analyzers showed interference or normal MetHb percentages. No other complications ensued, and cyanosis decreased over days. Since MetHb was discarded among other causes of cyanosis in a compatible clinical context, the diagnosis of sulfhemoglobinemia was made. The confirmatory method is not available in Chile. The presence of SulfHb is difficult to diagnose, confirmatory tests are not readily available, and it frequently interferes with arterial co-oximetry. This is attributed to a similar absorbance peak of both pigments in arterial blood. Venous co-oximetry can be useful in this context. SulfHb is a self-limited condition in most cases, however it must be differentiated from methemoglobinemia to avoid inappropriate treatments like methylene blue.


Assuntos
Metemoglobinemia , Sulfemoglobinemia , Feminino , Humanos , Metemoglobinemia/induzido quimicamente , Metemoglobinemia/diagnóstico , Sulfemoglobinemia/complicações , Oximetria/efeitos adversos , Cianose/complicações , Oxigênio
10.
Animals (Basel) ; 11(10)2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34679982

RESUMO

Several direct or indirect methods can be used to assess immunoglobulin G (IgG) concentrations in calves, which evaluates the transfer of passive immunity (TPI). Radial immunodiffusion (RID) is the gold standard method to measure serum IgG in bovines. Previous studies have shown that colostrum provides several molecules in addition to immunoglobulins, which play an important role in the passive immunity of the calf. However, no studies have yet determined the level of interference of these components in the immunity, health and survival of calves. In this sense, the objective of this study is to review the methods of evaluation available for the laboratory and field diagnosis of TPI in calves and discuss the main aspects of each technique. Several methods available for TPI evaluation in calves may provide insights into the various components of colostrum involved in passive immunity.

11.
Nat Commun ; 12(1): 1523, 2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33750782

RESUMO

Enterococcus faecalis is a commensal and nosocomial pathogen, which is also ubiquitous in animals and insects, representing a classical generalist microorganism. Here, we study E. faecalis isolates ranging from the pre-antibiotic era in 1936 up to 2018, covering a large set of host species including wild birds, mammals, healthy humans, and hospitalised patients. We sequence the bacterial genomes using short- and long-read techniques, and identify multiple extant hospital-associated lineages, with last common ancestors dating back as far as the 19th century. We find a population cohesively connected through homologous recombination, a metabolic flexibility despite a small genome size, and a stable large core genome. Our findings indicate that the apparent hospital adaptations found in hospital-associated E. faecalis lineages likely predate the "modern hospital" era, suggesting selection in another niche, and underlining the generalist nature of this nosocomial pathogen.


Assuntos
Infecção Hospitalar/microbiologia , Enterococcus faecalis/genética , Animais , Antibacterianos , Aves , Farmacorresistência Bacteriana/genética , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/isolamento & purificação , Genes MDR/genética , Genoma Bacteriano , Infecções por Bactérias Gram-Positivas/microbiologia , Hospitais , Especificidade de Hospedeiro , Humanos , Filogenia , Fatores de Virulência , Sequenciamento Completo do Genoma
12.
PLoS One ; 16(2): e0246208, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33539434

RESUMO

The purpose of this study was to determine the energy partition of pregnant F1 Holstein x Gyr with average initial body weight (BW) of 515.6 kg and Gyr cows with average initial BW of 435.1 kg at 180, 210 and 240 days of gestation, obtained using respirometry. Twelve animals in two groups (six per genetic group) received a restricted diet equivalent to 1.3 times the net energy for maintenance (NEm). The proportion of gross energy intake (GEI) lost as feces did not differ between the evaluated breeds and corresponded to 28.65% on average. The daily methane production (L/d) was greater for (P<0.05) F1 HxG compared to Gyr animals. However, when expressed as L/kg dry matter (DM) or as percentage of GEI there were no differences between the groups (P>0.05). The daily loss of energy as urine (mean of 1.42 Mcal/d) did not differ (P>0.05) between groups and ranged from 3.87 to 5.35% of the GEI. The metabolizable energy intake (MEI) of F1 HxG animals was greater (P < 0.05) at all gestational stages compared to Gyr cows when expressed in Mcal/d. However, when expressed in kcal/kg of metabolic BW (BW0,75), the F1 HxG cows had MEI 11% greater (P<0.05) at 240 days of gestation and averaged 194.39 kcal/kg of BW0,75. Gyr cows showed no change in MEI over time (P>0.05), with a mean of 146.66 kcal/kg BW0. 75. The ME used by the conceptus was calculated by deducting the metabolizable energy for maintenance (MEm) from the MEI, which was obtained in a previous study using the same cows prior to becoming pregnant. The values of NEm obtained in the previous study with similar non-pregnant cows were 92.02 kcal/kg BW0.75 for F1 HxG, and 76.83 kcal/kg BW0.75 for Gyr (P = 0.06). The average ME for pregnancy (MEp) was 5.33 Mcal/d for F1 HxG and 4.46 Mcal/d for Gyr. The metabolizability ratio, averaging 0.60, was similar among the evaluated groups (P>0.05). The ME / Digestible Energy (DE) ratio differed between groups and periods evaluated (P<0.05) with a mean of 0.84. The heat increment (HI) accounted for 22.74% and 24.38% of the GEI for F1 HxG and Gyr cows, respectively. The proportion of GEI used in the basal metabolism by pregnant cows in this study represented 29.69%. However, there were no differences between the breeds and the evaluation periods and corresponded to 29.69%. The mean NE for pregnancy (NEp) was 2.76 Mcal/d and did not differ between groups and gestational stages (P>0.05).


Assuntos
Ração Animal/análise , Dieta/veterinária , Metano/análise , Animais , Composição Corporal , Peso Corporal , Bovinos , Ingestão de Energia , Metabolismo Energético , Feminino , Idade Gestacional , Hibridização Genética , Gravidez
13.
J Dairy Sci ; 102(11): 10369-10378, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31495614

RESUMO

Cattle lameness is an important welfare concern that also has an economic impact on the dairy industry. It can be a significant problem among pasture-based herds. Our objectives were to identify cow- and herd-level factors related to lameness and hoof lesions in dairy cows grazing year-round in Minas Gerais, Brazil. We performed a cross-sectional study in 48 pasture-based dairy herds, visiting each farm in a single visit. We evaluated 2,262 cows for mobility score (0-3) and 392 cows for hoof lesions. We used a questionnaire and checklist to capture herd management data. All information obtained was used to build multivariable models. The factors associated with lameness were low body condition score, longer time spent in the corral, being kept in paddocks during the drought period, and poor hygiene. For hoof lesions, track features were the most significant factor in determining the likelihood of heel horn erosion, white line fissure, and sole hemorrhage-by more than 3 times. Different factors related to unhygienic conditions such as leg cleanliness, frequency of cleaning, and longer time spent in the corral were associated with infectious hoof lesions. Poor human-animal relationship was related to sole hemorrhage, but patient handling of cows on the track was a protective factor against interdigital hyperplasia. The results of this study suggest that improving hygiene conditions, track features, and cow handling can improve dairy cattle mobility scores in pasture-based farms under tropical conditions. These findings also represent a first step toward planning actions aimed at decreasing lameness and hoof lesions in the studied region.


Assuntos
Doenças dos Bovinos/etiologia , Indústria de Laticínios/métodos , Casco e Garras/patologia , Coxeadura Animal/etiologia , Criação de Animais Domésticos/métodos , Criação de Animais Domésticos/normas , Animais , Brasil/epidemiologia , Bovinos , Doenças dos Bovinos/epidemiologia , Lista de Checagem , Estudos Transversais , Meio Ambiente , Fazendas/classificação , Fazendas/estatística & dados numéricos , Feminino , Marcha , Manobra Psicológica , Higiene , Coxeadura Animal/epidemiologia , Modelos Logísticos , Registros/veterinária , Fatores de Risco , Inquéritos e Questionários , Clima Tropical
14.
Sci Rep ; 9(1): 13144, 2019 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-31511626

RESUMO

Lasiodiplodia theobromae (Botryosphaeriaceae, Ascomycota) is a plant pathogen and human opportunist whose pathogenicity is modulated by temperature. The molecular effects of temperature on L. theobromae are mostly unknown, so we used a multi-omics approach to understand how temperature affects the molecular mechanisms of pathogenicity. The genome of L. theobromae LA-SOL3 was sequenced (Illumina MiSeq) and annotated. Furthermore, the transcriptome (Illumina TruSeq) and proteome (Orbitrap LC-MS/MS) of LA-SOL3 grown at 25 °C and 37 °C were analysed. Proteins related to pathogenicity (plant cell wall degradation, toxin synthesis, mitogen-activated kinases pathway and proteins involved in the velvet complex) were more abundant when the fungus grew at 25 °C. At 37 °C, proteins related to pathogenicity were less abundant than at 25 °C, while proteins related to cell wall organisation were more abundant. On the other hand, virulence factors involved in human pathogenesis, such as the SSD1 virulence protein, were expressed only at 37 °C. Taken together, our results showed that this species presents a typical phytopathogenic molecular profile that is compatible with a hemibiotrophic lifestyle. We showed that L. theobromae is equipped with the pathogenesis toolbox that enables it to infect not only plants but also animals.


Assuntos
Ascomicetos/genética , Proteínas Fúngicas/genética , Perfilação da Expressão Gênica/métodos , Regulação Fúngica da Expressão Gênica , Proteômica/métodos , Temperatura , Ascomicetos/metabolismo , Ascomicetos/patogenicidade , Proteínas Fúngicas/metabolismo , Humanos , Doenças das Plantas/microbiologia , Virulência/genética , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Vitis/microbiologia
15.
PLoS One ; 14(4): e0211565, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31009472

RESUMO

The aim of this study was to describe energy partitioning in dairy crossbreed bulls fed tropical forage-based diets supplemented with different additives. Twenty F1 crossbred bulls (Holstein x Gyr) with initial and final live weight (LW) averages of 190 ± 17 and 275 ± 20 kg were fed sorghum (Sorghum bicolour) and Tanzania grass (Panicum maximum cv. Tanzania) silage (70:30 DM basis) with supplemented concentrate at a forage to concentrate ratio of 50:50. The bulls were allocated to four treatment: control groups (without additives), monensin [22 mg/kg monensin dry matter (DM)] (M), virginiamycin (30 mg/kg virginiamycin DM) (V), and combination (22 mg/kg DM of monensin and 30 mg/kg DM of virginiamycin) (MV), in a completely randomised design. The intake of gross energy (GE, MJ/d), digestible energy (DE, MJ/d), metabolizable energy (ME, MJ/d), as well as energy losses in the form of faeces, urine, methane, heat production (HE), and retained energy (RE) were measured. Faecal output was measured in apparent digestibility trial. Right after the apparent digestibility trial, urine samples were collected in order to estimate the daily urinary production of the animals. Heat and methane production were measured in an open circuit respirometry chamber. The intake of GE, DE, and ME of the animals receiving monensin and virginiamycin alone or in combination (MV) showed no differences (P>0.05) from the control treatment. However, the MV treatment reduced (P<0.05) the methane production (5.44 MJ/d) compared to the control group (7.33 MJ/d), expressed in MJ per day, but not when expressed related to gross energy intake (GEI) (CH4, % GEI) (P = 0.34). Virginiamycin and monensin alone or in combination did not change (P>0.05) the utilization efficiency of ME for weight gain, RE and net gain energy. This study showed that for cattle fed tropical forages, the combination of virginiamycin and monensin as feed additives affected their energy metabolism by a reduction in the energy lost as methane.


Assuntos
Ração Animal , Bovinos/fisiologia , Dieta/veterinária , Ingestão de Energia , Ração Animal/análise , Animais , Antibacterianos/farmacologia , Ingestão de Energia/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Masculino , Monensin/farmacologia , Panicum/metabolismo , Sorghum/metabolismo , Virginiamicina/farmacologia , Aumento de Peso/efeitos dos fármacos
16.
J Vet Diagn Invest ; 31(4): 554-556, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31023148

RESUMO

Cases of cranial superficial epigastric vein (CSEV) phlebitis with subsequent septicemia were observed in dairy farms in Minas Gerais, Brazil. Autopsy on 4 affected cows, from 2 farms, revealed CSEV thrombophlebitis with perivascular abscesses, pulmonary abscesses, valvular endocarditis, arthritis, thromboembolic nephritis, and renal infarcts. Microscopic examination revealed fibrosing and lymphoplasmacytic phlebitis with occasional endothelial loss, subendothelial areas of necrosis, and abundant fibrin deposition. Trueperella pyogenes, Escherichia coli, and Staphylococcus aureus were isolated from lesions of 3 different cows. Thrombophlebitis of the CSEV is a rare condition in dairy cows; however, it has become more frequent in dairy farms in southeastern Brazil after repeated venipuncture of this vein, likely with contaminated needles used for administration of oxytocin.


Assuntos
Infecções Bacterianas/veterinária , Doenças dos Bovinos/microbiologia , Sepse/veterinária , Tromboflebite/veterinária , Animais , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/microbiologia , Brasil/epidemiologia , Bovinos , Doenças dos Bovinos/epidemiologia , Feminino , Sepse/epidemiologia , Sepse/microbiologia , Tromboflebite/epidemiologia , Tromboflebite/microbiologia
17.
Mycologia ; 110(4): 642-653, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30062925

RESUMO

Lasiodiplodia theobromae is a phytopathogenic fungus that causes diseases not only in a broad number of plant hosts but also occasionally in humans. The capacity of L. theobromae to produce bioactive metabolites at 25 C (environmental mean temperature) and at 37 C (body mean temperature) was investigated. Two strains, CAA019 and CBS339.90, isolated respectively from a coconut tree and a human patient were characterized. The phytotoxicity and cytotoxicity (on mammalian cells) of the secretomes of both strains of L. theobromae were investigated. Also, phytotoxicity and cytotoxicity of pure compounds were evaluated. The phytotoxicity of the secretome of strain CAA019 was higher than the phytotoxicity of the secretome of strain CBS339.90 at 25 C. However, the phytotoxicity for both strains decreased when they were grown at 37 C. Only the secretome of strain CBS339.90 grown at 37 C induced up to 90% Vero and 3T3 cell mortality. This supports the presence of different metabolites in the secretome of strains CAA019 and CBS339.90. Metabolites typical of L. theobromae were isolated and identified from organic extracts of the secretome of both strains (e.g., 3-indolecarboxylic acid, jasmonic acid, lasiodiplodin, four substituted 2-dihydrofuranones, two melleins, and cyclo-(Trp-Ala)). Also, metabolites such as scytalone, not previously reported for this species, were isolated and identified. Metabolite production is affected by strain and temperature. In fact, some metabolites are strain specific (e.g., lasiodiplodin) and some metabolites are temperature specific (e.g., jasmonic acid). Although more strains should be characterized, it may be anticipated that temperature tuning of secondary-metabolite production emerges as a putative contributing factor in the modulation of L. theobromae pathogenicity towards plants, and also towards mammalian cells.


Assuntos
Ascomicetos/química , Ascomicetos/metabolismo , Metabolismo Secundário , Temperatura , Árvores/microbiologia , Animais , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/isolamento & purificação , Linhagem Celular , Chlorocebus aethiops , Cocos/microbiologia , Ciclopentanos/metabolismo , Ciclopentanos/toxicidade , Humanos , Metaboloma , Micotoxinas/biossíntese , Micotoxinas/metabolismo , Oxilipinas/metabolismo , Oxilipinas/toxicidade , Filogenia , Células Vero , Zearalenona/análogos & derivados , Zearalenona/metabolismo , Zearalenona/toxicidade
18.
Ticks Tick Borne Dis ; 7(1): 80-84, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26381444

RESUMO

Bovine anaplasmosis is a disease caused by the intraerythrocytic rickettsia species Anaplasma marginale and results in great economic losses in tropical and subtropical regions. Vertical transmission is an important phenomenon that contributes to the persistence of different strains of the agent within the same herd. The identification of new strains and genetic characterization studies are essential to understanding their epidemiology and virulence and for vaccine development. The aim of this study was to perform molecular and phylogenetic characterizations of a new vertically transmitted strain from A. marginale and to evaluate its virulence by experimental inoculation of rickettsia-free calves. Thirty newborn Holstein calves were subjected to molecular tests for the detection of A. marginale, Babesia bovis and Babesia bigemina. Calves positive for A. marginale (n=3) were splenectomized and monitored for the clinical manifestations of anaplasmosis. Blood samples from one of the calves that presented rickettsemia of 42.8% and spontaneous recovery of clinical parameters were used for molecular and phylogenetic characterization (msp1a gene), and inoculum production was used for the evaluation of virulence. This strain was identified as UFMG3. Three tandem repeat forms (13 and MGI19) were identified from the analysis of the msp1a gene, in which the form MGI19 appeared twice. Analysis of these repeats revealed the presence of the sequences QASTSS and SSASGQQQESS and of aspartic acid (D) at position 20 of both repeats. Phylogenetic analysis showed a close relationship among the UFMG3, MGI19 and UFMG2 strains. For virulence evaluation, six Holstein calves were inoculated intravenously with 2×10(7)A. marginale UFMG3-infected erythrocytes. The calves showed maximum rickettsemia of 5.1%, a moderate decrease in packed cell volume and spontaneous recovery of clinical parameters without the need for treatment. The results of experimental inoculation suggest that the strain A. marginale UFMG3 has low virulence and potential application for use as a live vaccine against A. marginale.


Assuntos
Anaplasma marginale/genética , Anaplasmose/parasitologia , Doenças dos Bovinos/microbiologia , Anaplasma marginale/patogenicidade , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Feminino , Variação Genética , Transmissão Vertical de Doenças Infecciosas , Masculino , Filogenia , Gravidez , Esplenectomia , Virulência
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