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1.
JDS Commun ; 5(2): 134-138, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38482115

RESUMO

Around parturition, dairy cows inevitably and perhaps necessarily experience some degree of systemic inflammation, but when excessive or dysregulated, it may contribute to health disorders. As immune activation decreases blood Ca, greater extracellular Ca availability may potentiate or sustain inflammation. We hypothesized that in clinically healthy multiparous cows, postpartum administration of supplemental Ca would increase serum concentrations of inflammatory markers. The objective of this randomized controlled trial was to investigate a possible effect of supplementing calcium (Ca) on postpartum systemic inflammation in dairy cows. Healthy cows (n = 101) from 2 commercial dairy farms in Ontario calving into parity 2, 3, or 4 were enrolled. Cows were blocked by parity and randomly assigned to receive an oral bolus of Ca (42 g of Ca) within 12 h after calving and a second bolus 12 h later (TRT; n = 51), or no Ca supplementation (CON; n = 49). Concentrations in serum of total Ca (tCa), haptoglobin (Hp), and albumin (ALB) were assessed at d 0 (within 12 h postpartum), 0.5 (12 h later), 1, 2, 4, 6, and 8 postpartum; ionized calcium was assessed at d 0, 0.5, 2, and 4, and lipopolysaccharide-binding protein (LBP) and serum amyloid A (SAA) were assessed at d 0, 2, and 4. Multivariable linear regression models of each outcome accounting for repeated measures included treatment, parity (2 vs. 3 or 4), farm, sampling day, baseline concentration (d 0), and interactions of treatment with farm, parity, and day. Results are presented as least squares means and 95% confidence intervals. Concentration of tCa tended to be greater at d 0.5 (TRT 2.07 mmol/L [2.03-2.12]; CON 2.01 [1.96-2.06]) but was lesser at d 2 (TRT 2.18 [2.13-2.23]; CON 2.27 [2.23-2.32]) in TRT than CON cows. Concentrations of LBP were greater in TRT (2.28 ng/mL [2.06-2.50]) than CON (1.99 [1.77-2.21]) in parity 2, but not different in older cows (TRT 2.28 ng/mL [2.06-2.50]; CON 1.99 [1.77-2.21]). Concentrations of SAA were greater in TRT than CON cows at d 2 (TRT 135 ug/mL [124-146]; CON 114 [75-106]). Treatment had no effect on ALB or Hp. In clinically healthy cows, oral Ca supplementation had a small transient effect on blood tCa and little indication of increasing inflammation based on the analytes evaluated.

2.
J Dairy Sci ; 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38331174

RESUMO

The objective of this cross-sectional study was to determine associations between calf management practices, the number of antimicrobial treatments, and antimicrobial resistance in pre-weaned heifers on Canadian dairy farms. A composite of 5 fecal samples from pre-weaned calves was collected from 142 dairy farms in 5 provinces and analyzed for phenotypic antimicrobial susceptibility with the microbroth dilution method. Questionnaires were used to capture herd characteristics and calf management practices used on the farm. Calf treatment records were collected during the farm visits. Escherichia coli was isolated from all 142 fecal samples with the highest resistance to tetracycline (41%), followed by sulfisoxazole (36%), streptomycin (32%), chloramphenicol (28%), ampicillin (16%), trimethoprim-sulfamethoxazole (15%), ceftriaxone (4.2%), cefoxitin (2.8%), amoxicillin-clavulanic acid (2.1%), ciprofloxacin (2.1%), nalidixic acid (2.1%), azithromycin (1.4%), and gentamicin (1.4%). Multidrug resistance was observed in 37% of E. coli isolates. Three-quarters of farms used fresh colostrum as the most common type of colostrum fed to calves. Colostrum quality was checked on 49% of farms, but the transfer of passive immunity was only checked on 32% of farms in the last 12 mo. Almost 70% of farms used straw or hay or a combination as the bedding material for calves. Among the 142 farms, a complete set of calf records were collected from 71 farms. In a multivariable logistic regression model, farms with ≥1.99 - 32.57 antimicrobial treatments/calf-year were 3.2 times more likely to have multidrug resistant E. coli in calf feces compared farms with <1.99 antimicrobial treatments/calf-year. Farms using hay or straw beddings were 5.1 times less likely to have multidrug resistant E. coli compared with those with other bedding materials including shavings or sawdust. Bedding management practices on farms may need to be investigated to reduce the potential impact on disseminating multidrug resistant bacteria.

3.
J Dairy Sci ; 107(5): 3168-3184, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37977442

RESUMO

Our objective was to investigate associations of postpartum health with serum progesterone (P4) concentrations after first artificial insemination (AI), expression of interferon-stimulated genes (ISG) in blood leukocytes, and serum pregnancy-associated glycoprotein (PAG) during early pregnancy in dairy cows. In this observational study, Holstein cows (n = 475) from 2 commercial herds were enrolled 3 wk before expected parturition. Body condition score (BCS) and lameness were assessed at enrollment, and total Ca, haptoglobin, and nonesterified fatty acids (NEFA) were measured in serum at 2 and 6 ± 2 d in milk (DIM). Blood ß-hydroxybutyrate and metritis were evaluated at 4, 8, 11, and 15 ± 2 DIM, and purulent vaginal discharge (PVD) and endometritis based on endometrial cytology were diagnosed at 35 DIM. Onset of cyclicity was assessed by biweekly P4 measurements. The BCS was assessed at enrollment and at 63 DIM, and lameness at enrollment and at 21 and 49 DIM. First AI was based on estrus detection until ∼75 DIM, or synchronization for timed AI thereafter. Serum P4 was measured at d 8 and 12 after first AI; expression of ISG (ISG15 and RTP4) in blood leukocytes was assessed at d 19; and PAG in serum of pregnant cows was measured at d 29, 33, and 40. Multivariable linear regression models were built including health variables (with metabolites categorized via receiver operating characteristic curve analysis) and covariates (season, milk yield, AI method, DIM), accounting for pregnancy status (for ISG and PAG models), repeated measures (for P4 and PAG models), and herd as random. Results are reported comparing cows affected versus unaffected by each predictor. Serum P4 concentrations were lesser at d 8 after AI in cows that had total Ca ≤2.09 mM (3.6 vs. 4.0 ± 0.2 ng/mL) at 2 DIM or a clinical disease (3.7 vs. 4.0 ± 0.2 mg/mL), and P4 tended to be lesser at d 8 in cows that had PVD (3.6 vs. 4.0 ± 0.2 ng/mL) or any uterine disease (3.7 vs. 4.1 ± 0.2 ng/mL). Among cows pregnant at d 29, relative ISG15 expression (fold change) at d 19 was greater in cows that had lameness (5.10 [4.18-6.18] vs. 3.14 [3.10-3.19]) but tended to be lesser in cows that had endometritis (3.20 [2.89-3.54] vs. 4.29 [4.20-4.35]), and relative expression of RTP4 tended to be lesser in cows that had displaced abomasum (1.02 [0.62-1.67] vs. 1.75 [1.73-1.78]). Serum PAG was lesser at d 29 (3.8 vs. 4.2 ± 0.2 sample-to-positive ratio [S:P]) in cows that had NEFA ≥0.73 mM at 6 DIM, and lesser at d 33 (3.9 vs. 4.5 ± 0.2 S:P) and 40 (3.1 vs. 3.7 ± 0.2 S:P) in cows that had prepartum BCS ≥3.75. These findings suggest long-term effects of metabolic or reproductive tract disorders on luteal function after first AI, pregnancy recognition signaling, and placental function during early pregnancy. These associations may partially explain some of the pathways linking postpartum health and fertility in dairy cows.

4.
J Dairy Sci ; 107(3): 1630-1644, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37820756

RESUMO

Our objective was to describe associations of postpartum health with pregnancy and pregnancy loss (P-LOSS) from d 19 to 40 after first postpartum artificial insemination (AI) in lactating Holstein cows. In 2 commercial dairy herds in Ontario, Canada, 468 Holstein cows were enrolled 21 ± 3 d before expected parturition when body condition score (BCS) and lameness were assessed. Serum total Ca, haptoglobin (Hp), and nonesterified fatty acids (NEFA) were measured at 2 and 6 ± 2 d in milk (DIM). Blood ß-hydroxybutyrate (BHB) measurement and metritis detection were done at 4, 8, 11, and 15 ± 2 DIM. Cows were examined for endometritis (ENDO; ≥11.5% polymorphonuclear cells in endometrial cytology) and purulent vaginal discharge (PVD) at 35 ± 3 DIM. Lameness was assessed again at 21 and 49 ± 3 DIM and BCS at 63 ± 3 DIM. First postpartum AI occurred primarily (86%) based on detection of estrus by activity monitors, on average (± standard deviation) at 65 ± 9 DIM, and the remaining cows received timed AI at 86 ± 18 DIM. Serum progesterone (P4) was measured on d 8 and 12 after AI, and pregnancy at first AI (P/AI) was estimated by the expression of ISG15 in peripheral blood leukocytes at d 19 after AI and by pregnancy-associated glycoprotein in serum at d 29, 33, and 40 after AI. Each metabolite (Ca, Hp, NEFA, and BHB) was categorized above or below a cut-point identified with receiver operating characteristic curve analysis associated with P/AI confirmed by ultrasound at d 33 from a larger data set. Data were analyzed using multivariable mixed logistic regression models, accounting for parity, health variables, covariates (season at calving and at AI, milk yield at first Dairy Herd Improvement Association test [categorized into terciles], AI method, and DIM), and herd. The proportions of cows classified pregnant at d 19, 29, 33, and 40 after AI were 64%, 54%, 50%, and 45%, respectively. At d 19 after AI, P/AI was less likely in cows diagnosed with ENDO (52% vs. 69%) or PVD (54% vs. 67%). At d 29, P/AI was less likely in cows with Hp ≥1.54 g/L at 2 DIM (38% vs. 55%) or PVD (35% vs. 56%). Both metritis and ENDO were associated with decreased P/AI at d 40 after AI. Cows diagnosed with metritis had greater risk of P-LOSS from d 19 to 29 (43% vs. 22%) or from d 33 to 40 (37% vs. 7%) than cows without metritis. From d 29 to 33, the risk of P-LOSS was greater in cows with NEFA ≥0.73 mM at 2 DIM (13% vs. 5%) or BCS ≤2.75 at 63 DIM (14% vs. 5%). The concentration of P4 on d 8 after AI was positively associated with P/AI at d 29, 33, and 40, and negatively associated with P-LOSS from d 19 to 29. Postpartum health disorders, particularly reproductive tract disease, can have detrimental effects on early pregnancy establishment and on pregnancy maintenance from d 19 to 40 after AI.


Assuntos
Doenças dos Bovinos , Transtornos Puerperais , Feminino , Gravidez , Bovinos , Animais , Ácidos Graxos não Esterificados , Lactação , Coxeadura Animal , Aborto Animal , Período Pós-Parto , Transtornos Puerperais/veterinária , Haptoglobinas , Ontário
5.
J Dairy Sci ; 106(12): 9451-9473, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37678796

RESUMO

The objective of this prospective observational study was to investigate associations of postpartum health with estrus detection (ED) by activity monitors and pregnancy outcomes in dairy cows. A total of 1,743 Holstein cows from 2 commercial dairy herds in Ontario, Canada were enrolled 3 wk before expected parturition and examined for health variables until 9 wk postpartum. Body condition score (BCS) and lameness were measured at 3 wk prepartum, and serum concentrations of total Ca, haptoglobin (Hp), and nonesterified fatty acids were measured at 2 and 6 ± 2 d in milk (DIM), and blood ß-hydroxybutyrate (BHB) and metritis were assessed at 4, 8, 11, and 15 ± 2 DIM. Cows were examined for purulent vaginal discharge (PVD) and endometritis (ENDO) by endometrial cytology at wk 5, for lameness at wk 3 and 7, for BCS at wk 9 postpartum, and for time to onset of cyclicity by biweekly serum progesterone (P4) measurements. Additional disease data were obtained from farm records. Reproductive management for first AI was primarily based on ED by activity monitors until at least 75 DIM, and cows not detected in estrus were synchronized. Data were analyzed in multivariable logistic or Cox proportional hazards regression models including blood markers, health variables, potential covariates, and herd as a random effect. Estrus was detected in 77% of primiparous and 66% of multiparous cows between 50 or 55 DIM and 75 DIM. In 1,246 cows, the model-predicted probability of ED (percentage point difference) was lower in cows that had retained placenta (-14%), ENDO (-7%), PVD (-8%), delayed cyclicity (no P4 > 1 ng/mL by wk 9; -12%), or ≥0.5-point BCS loss (-14%) compared with cows without each of these risk factors, and it was negatively associated with blood BHB at 15 DIM. Considering only variables measured on farm (not requiring laboratory analysis), the probability of ED was lower (56 vs. 81%) in cows with >1 risk factor compared with cows without risk factors. The predicted probability of pregnancy at first artificial insemination (percentage point difference) was lower in cows that had ENDO (-7%) or PVD (-7%), and negatively associated with serum Hp at 6 ± 2 DIM. In cows detected in estrus by 75 DIM (n = 888), risk factors for reduced pregnancy rate by 250 DIM (adjusted hazard ratio (AHR); 95% confidence intervals) included difficult calving (AHR: 0.67; 0.45 to 1.00), metritis (AHR: 0.79; 0.61 to 1.01), PVD (AHR: 0.79; 0.65 to 0.97), or lameness (AHR: 0.79; 0.62 to 1.01), and it was negatively associated with serum Hp at 6 ± 2 DIM. Monitoring postpartum health may be used to identify cows that are more or less likely to be detected in estrus by activity monitors and to become pregnant in a timely manner. This would support a selective reproductive management program with targeted interventions.


Assuntos
Doenças dos Bovinos , Endometrite , Animais , Bovinos , Feminino , Gravidez , Endometrite/veterinária , Estro , Detecção do Estro , Lactação , Coxeadura Animal , Ontário , Período Pós-Parto , Reprodução
6.
J Dairy Sci ; 105(11): 9084-9097, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36175237

RESUMO

The objective of this cross-sectional study was to investigate the relationship between management practices and antimicrobial use in heifer calves on Canadian dairy farms. Questionnaires on calf management practices, herd characteristics, and calf treatment records were administered on 147 dairy farms in 5 provinces during annual farm visits in a multiyear, nationwide research project (Canadian Dairy Network for Antimicrobial Stewardship and Resistance: CaDNetASR). Questions focused on the calf caregiver, calving pen, colostrum management, milk feeding, grouping, bedding management, and age when male calves were sold. Antimicrobial treatment records were collected on each farm from either an electronic herd management system or paper-based records. Newborn heifers born in the last 12 mo were identified retrospectively and followed to 60 d of age, with antimicrobial treatments and dates of sale or death extracted for further analysis. A multivariable linear regression model was developed with the natural log of the number of antimicrobial treatments per calf-year as the dependent variable, and categorized calf management practices and farm characteristics as the independent variables. A complete data set of records on 7,817 calves was retrieved from 74 farms based on completeness of calf records. A total of 2,310 calves were treated at least once with an antimicrobial, and 7,307 individual antimicrobial treatments were recorded. Among the reasons for antimicrobial use, respiratory disease (54%) was most common, followed by diarrhea (20%), presence of a fever (3%), and umbilical disease (2%). Florfenicol (33% of recorded treatments), penicillin (23%), and trimethoprim-sulfamethoxazole (18%) were commonly used, whereas fluoroquinolones (4%), and ceftiofur (1%) were used less commonly. Farms (31%) commonly had 0-1.0 antimicrobial treatments/calf-year (median: 2.2 treatments/calf-year; interquartile range: 0.64-6.43 treatments/calf-year). Defined daily dose (DDD) per calf-year was calculated based on the Canadian bovine standards. Among the 74 farms, florfenicol (1.35 DDD/calf-year) and macrolides (0.73 DDD/calf-year) were used most, whereas ceftiofur (0.008 DDD/calf-year) was the lowest. The final multivariable linear regression model indicated that farms that fed transition milk had fewer than half the number of antimicrobial treatments per calf-year than those who did not feed transition milk. The number of antimicrobial treatments per calf-year in preweaning calves was low on many farms, and there was low use of highly important drugs for human medicine. The effect of feeding transition milk should be investigated regarding potential effects on antimicrobial use and disease prevention.


Assuntos
Indústria de Laticínios , Combinação Trimetoprima e Sulfametoxazol , Gravidez , Bovinos , Animais , Masculino , Feminino , Humanos , Estudos Transversais , Estudos Retrospectivos , Canadá , Antibacterianos/uso terapêutico , Fluoroquinolonas , Macrolídeos , Penicilinas
7.
Microb Ecol ; 82(1): 156, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34013437
8.
Microb Ecol ; 82(1): 145-155, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33483845

RESUMO

Fungi are mediators of the nitrogen and carbon cycles in terrestrial ecosystems. Examining how nitrogen uptake and organic matter decomposition potential differs in fungi can provide insight into the underlying mechanisms driving fungal ecological processes and ecosystem functioning. In this study, we assessed the frequency of genes encoding for specific enzymes that facilitate nitrogen uptake and organic matter decomposition in 879 fungal genomes with fungal taxa grouped into trait-based categories. Our linked gene-trait data approach revealed that gene frequencies vary across and within trait-based groups and that trait-based categories differ in trait space. We present two examples of how this linked gene-trait approach can be used to address ecological questions. First, we show that this type of approach can help us better understand, and potentially predict, how fungi will respond to environmental stress. Specifically, we found that trait-based categories with high nitrogen uptake gene frequency increased in relative abundance when exposed to high soil nitrogen enrichment. Second, by comparing frequencies of nitrogen uptake and organic matter decomposition genes, we found that most ectomycorrhizal fungi in our dataset have similar gene frequencies to brown rot fungi. This demonstrates that gene-trait data approaches can shed light on potential evolutionary trajectories of life history traits in fungi. We present a framework for exploring nitrogen uptake and organic matter decomposition gene frequencies in fungal trait-based groups and provide two concise examples on how to use our framework to address ecological questions from a mechanistic perspective.


Assuntos
Ecossistema , Micorrizas , Fungos/genética , Nitrogênio , Solo , Microbiologia do Solo
9.
Oncogene ; 39(30): 5292-5306, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32555332

RESUMO

MicroRNAs play an important role in the regulation of mRNA translation and have therapeutic potential in cancer and other diseases. To profile the landscape of microRNAs with significant cytotoxicity in the context of glioblastoma (GBM), we performed a high-throughput screen in adult and pediatric GBM cells using a synthetic oligonucleotide library representing all known human microRNAs. Bioinformatics analysis was used to refine this list and the top seven microRNAs were validated in a larger panel of GBM cells using state-of-the-art in vitro assays. The cytotoxic effect of our most relevant candidate was assessed in a preclinical model. Our screen identified ~100 significantly cytotoxic microRNAs with 70% concordance between cell lines. MicroRNA-1300 (miR-1300) was the most potent and robust candidate. We observed a striking binucleated phenotype in miR-1300 transfected cells due to cytokinesis failure followed by apoptosis. This was also observed in two stem-like patient-derived cultures. We identified the physiological role of miR-1300 as a regulator of endomitosis in megakaryocyte differentiation where blockade of cytokinesis is an essential step. In GBM cells, where miR-1300 is normally not expressed, the oncogene Epithelial Cell Transforming 2 (ECT2) was validated as a direct key target. ECT2 siRNA phenocopied the effects of miR-1300, and ECT2 overexpression led to rescue of miR-1300 induced binucleation. We showed that ectopic expression of miR-1300 led to decreased tumor growth in an orthotopic GBM model. Our screen provides a resource for the neuro-oncology community and identified miR-1300 as a novel regulator of endomitosis with translatable potential for therapeutic application.


Assuntos
Neoplasias Encefálicas/genética , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , MicroRNAs/genética , Regiões 3' não Traduzidas/genética , Adulto , Neoplasias Encefálicas/patologia , Diferenciação Celular/genética , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Criança , Glioblastoma/patologia , Ensaios de Triagem em Larga Escala/métodos , Humanos , Megacariócitos/citologia , Megacariócitos/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo
10.
Epidemiol Infect ; 147: e250, 2019 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-31496448

RESUMO

Currently no national guidelines exist for the management of scabies outbreaks in residential or nursing care homes for the elderly in the United Kingdom. In this setting, diagnosis and treatment of scabies outbreaks is often delayed and optimal drug treatment, environmental control measures and even outcome measures are unclear. We undertook a systematic review to establish the efficacy of outbreak management interventions and determine evidence-based recommendations. Four electronic databases were searched for relevant studies, which were assessed using a quality assessment tool drawing on STROBE guidelines to describe the quality of observational data. Nineteen outbreak reports were identified, describing both drug treatment and environmental management measures. The quality of data was poor; none reported all outcome measures and only four described symptom relief measures. We were unable to make definitive evidence-based recommendations. We draw on the results to propose a framework for data collection in future observational studies of scabies outbreaks. While high-quality randomised controlled trials are needed to determine optimal drug treatment, evidence on environmental measures will need augmentation through other literature studies. The quality assessment tool designed is a useful resource for reporting of outcome measures including patient-reported measures in future outbreaks.


Assuntos
Surtos de Doenças/prevenção & controle , Transmissão de Doença Infecciosa/prevenção & controle , Controle de Infecções/métodos , Escabiose/epidemiologia , Escabiose/prevenção & controle , Idoso , Infecções Comunitárias Adquiridas/diagnóstico , Infecções Comunitárias Adquiridas/epidemiologia , Infecções Comunitárias Adquiridas/prevenção & controle , Infecções Comunitárias Adquiridas/terapia , Infecção Hospitalar/diagnóstico , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/prevenção & controle , Infecção Hospitalar/terapia , Humanos , Casas de Saúde , Escabiose/diagnóstico , Escabiose/terapia , Reino Unido/epidemiologia
11.
J Appl Microbiol ; 127(4): 1192-1206, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31230390

RESUMO

AIMS: To evaluate efficacy of Saccharomyces cerevisiae fermentate prebiotic (EH) in protection of intestinal barrier integrity in rats during heat stress, to analyze the impact of heat stress and preventive treatment with EH on the structure of the gut microbiota. METHODS AND RESULTS: Two groups of rats were treated orally with EH or phosphate-buffered saline for 14 days. On day 15, half of the rats in each group were exposed to heat stress conditions, while control animals were kept at room temperature. Histological and Western blot analyses of the intestine, culture-based microbiological analysis and high-throughput 16S rRNA sequencing for the gut microbiota were performed for each rat. Exposure of animals to heat stress conditions resulted in inhibition of tight junction (TJ) proteins expression, decrease of Paneth and goblet cells, decrease of beneficial and increase of pathogenic bacteria. Oral treatment of rats with EH before stress significantly prevents these adverse effects by elevation of the gut beneficial bacteria, particularly butyrate-producing bacteria. CONCLUSIONS: Essential effect of EH in protection of intestinal barrier integrity during heat stress is connected with beneficial modulation of the gut microbiota. SIGNIFICANCE AND IMPACT OF THE STUDY: Our results will contribute to the development of new approaches to prevention of heat stress-related complications.


Assuntos
Microbioma Gastrointestinal/fisiologia , Resposta ao Choque Térmico/efeitos dos fármacos , Intestinos , Prebióticos , Saccharomyces cerevisiae/metabolismo , Animais , Fermentação , Intestinos/microbiologia , Intestinos/fisiologia , Ratos
12.
J Dairy Sci ; 101(10): 9521-9526, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30100499

RESUMO

Udder edema (UE) is a common condition of cows around calving, but its effects are not well characterized. The objectives of this study were to determine the associations of UE with the incidence of health disorders and with milk yield and reproduction in dairy cows in early lactation. On 3 commercial farms, UE was scored weekly on 1,346 cows, on a scale of 0 to 3, from 1 wk before calving to 3 wk after calving. Among cows with complete UE scores, 30% never had edema, 12% had edema only prepartum, 11% had it only postpartum, and 48% had edema prepartum and in at least 1 wk postpartum. Udder edema was associated with a greater incidence of clinical mastitis before 30 d in milk (5 vs. 2%). Subclinical ketosis (blood ß-hydroxybutyrate ≥1.2 mmol/L) was more prevalent at wk 2 (11 vs. 6%) postpartum among cows with UE. No association was observed of UE with other diseases or culling in early lactation. In a subset of 912 cows with complete UE and 3 test-days of milk yield data, differences were observed in yield at test d 1 among UE categories. Cows with UE only prepartum produced less milk (39.9 kg/d) than cows with UE postpartum only (42.4 kg/d) and cows with UE both prepartum and postpartum (41.6 kg/d), none of which differed from cows without UE (40.9 kg/d). Udder edema was not associated with the prevalence of anovulation, or the time to or probability of pregnancy at first insemination, yet to 300 d in milk, cows that had UE postpartum had a shorter time from calving to pregnancy than cows without UE. The associations of UE with health and productivity are mixed, and the mechanisms underlying UE and its effects merit further investigation.


Assuntos
Bovinos/fisiologia , Edema/veterinária , Lactação/fisiologia , Glândulas Mamárias Animais/patologia , Leite/metabolismo , Animais , Dieta , Edema/fisiopatologia , Feminino , Período Pós-Parto , Gravidez
13.
J Dairy Sci ; 101(10): 9016-9027, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30100511

RESUMO

The objectives were to determine the effects of a rumen-protected blend of B vitamins and choline (RPBC) on the incidence of health disorders, milk yield, and reproduction in early lactation and the effects on gene expression and liver fat infiltration. A randomized controlled trial in 3 commercial dairy herds (n = 1,346 cows with group as the experimental unit; experiment 1) and a university research herd (n = 50 cows with cow as the experimental unit; experiment 2) evaluated the use of 100 g/cow per d of commercially available proprietary RPBC supplement (Transition VB, Jefo, St. Hyacinthe, Quebec, Canada), or a placebo, fed 3 wk before to 3 wk after calving. In experiment 2 liver biopsies were taken at 4 and 14 ± 1 d in milk to measure triacylglycerol concentrations and expression of 28 genes selected to represent relevant aspects of liver metabolism. Treatment effects were assessed using multivariable mixed logistic regression models for binary health and reproductive outcomes; linear regression models for milk yield, dry matter intake, and liver outcomes; and survival analysis for time insemination and pregnancy. In experiment 1, treatment did not have an effect on the incidence of hyperketonemia (blood ß-hydroxybutyrate ≥ 1.2 mmol/L; cumulative incidence to 3 wk postpartum of 28 to 30%), clinical health disorders, or udder edema. The prevalence of anovulation at 8 wk postpartum was 11% in the treatment group and 23% in the control but did not differ statistically given group-level randomization. Pregnancy at first insemination (33 and 35%) and median time to pregnancy to 200 d in milk (96 and 97 d) were not different between treatment and control, respectively. No difference was observed between treatment groups in milk yield or components through the first 3 Dairy Herd Improvement Association test days (44 kg/d in both groups, accounting for parity and components). In experiment 2, there were no differences between treatment groups in feed intake. Mean blood ß-hydroxybutyrate was lower at wk 3 in RPBC (0.6 vs. 0.9 ± 0.12 mmol/L) with no difference between treatments for mean blood concentrations of fatty acids (wk -1 or 1) and ß-hydroxybutyrate at wk 1 or 2. The gene for acyl-CoA oxidase 1 (ACOX1) had lower mRNA abundance in RPBC with no difference between treatments for the other genes, but the expression of half of the genes assessed differed with days in milk. Liver triacylglycerol was lower in primiparous cows at 4 d in milk in RPBC (2.0 vs. 4.4 ± 1.2%) but not at 14 d in milk (2.2 vs. 3.2 ± 0.97%) with no treatment effect in multiparous cows (4.6 ± 0.8%). Accounting for parity, days in milk, fat and protein percentages, repeated test days, and a random effect of cow, no significant difference was observed between treatments in milk yield across the first 3 Dairy Herd Improvement Association tests (41.2 ± 1.3 in RPBC vs. 38.0 ± 1.4 kg/d in control). Under the diet and management conditions of the field study including low prevalence of clinical health disorders, in experiment 1 we did not detect a benefit of RPBC, but in experiment 2 liver fat content decreased in primiparous cows.


Assuntos
Bem-Estar do Animal , Bovinos/fisiologia , Colina/administração & dosagem , Lactação/fisiologia , Complexo Vitamínico B/administração & dosagem , Animais , Dieta , Feminino , Leite , Período Pós-Parto , Gravidez , Rúmen
14.
Br J Clin Pharmacol ; 84(10): 2218-2230, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29863746

RESUMO

Paracetamol (acetaminophen) is the most commonly used drug in the world, with a long record of use in acute and chronic pain. In recent years, the benefits of paracetamol use in chronic conditions has been questioned, notably in the areas of osteoarthritis and lower back pain. Over the same period, concerns over the long-term adverse effects of paracetamol use have increased, initially in the field of hypertension, but more recently in other areas as well. The evidence base for the adverse effects of chronic paracetamol use consists of many cohort and observational studies, with few randomized controlled trials, many of which contradict each other, so these studies must be interpreted with caution. Nevertheless, there are some areas where the evidence for harm is more robust, and if a clinician is starting paracetamol with the expectation of chronic use it might be advisable to discuss these side effects with patients beforehand. In particular, an increased risk of gastrointestinal bleeding and a small (~4 mmHg) increase in systolic blood pressure are adverse effects for which the evidence is particularly strong, and which show a degree of dose dependence. As our estimation of the benefits decreases, an accurate assessment of the harms is ever more important. The present review summarizes the current evidence on the harms associated with chronic paracetamol use, focusing on cardiovascular disease, asthma and renal injury, and the effects of in utero exposure.


Assuntos
Acetaminofen/efeitos adversos , Analgésicos não Narcóticos/efeitos adversos , Dor Crônica/tratamento farmacológico , Acetaminofen/administração & dosagem , Acetaminofen/normas , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/prevenção & controle , Analgésicos não Narcóticos/administração & dosagem , Analgésicos não Narcóticos/normas , Asma/induzido quimicamente , Asma/epidemiologia , Asma/prevenção & controle , Doenças Cardiovasculares/induzido quimicamente , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Dor Crônica/etiologia , Feminino , Humanos , Incidência , Assistência de Longa Duração/métodos , Assistência de Longa Duração/normas , Exposição Materna/efeitos adversos , Transtornos do Neurodesenvolvimento/induzido quimicamente , Transtornos do Neurodesenvolvimento/epidemiologia , Transtornos do Neurodesenvolvimento/prevenção & controle , Estudos Observacionais como Assunto , Guias de Prática Clínica como Assunto , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Efeitos Tardios da Exposição Pré-Natal/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto , Medição de Risco/métodos
15.
J Evol Biol ; 30(10): 1796-1809, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28665024

RESUMO

Interactions between the structure of a metabolic network and its functional properties underlie its evolutionary diversification, but the mechanism by which such interactions arise remains elusive. Particularly unclear is whether metabolic fluxes that determine the concentrations of compounds produced by a metabolic network, are causally linked to a network's structure or emerge independently of it. A direct empirical study of populations where both structural and functional properties vary among individuals' metabolic networks is required to establish whether changes in structure affect the distribution of metabolic flux. In a population of house finches (Haemorhous mexicanus), we reconstructed full carotenoid metabolic networks for 442 individuals and uncovered 11 structural variants of this network with different compounds and reactions. We examined the consequences of this structural diversity for the concentrations of plumage-bound carotenoids produced by flux in these networks. We found that concentrations of metabolically derived, but not dietary carotenoids, depended on network structure. Flux was partitioned similarly among compounds in individuals of the same network structure: within each network, compound concentrations were closely correlated. The highest among-individual variation in flux occurred in networks with the strongest among-compound correlations, suggesting that changes in the magnitude, but not the distribution of flux, underlie individual differences in compound concentrations on a static network structure. These findings indicate that the distribution of flux in carotenoid metabolism closely follows network structure. Thus, evolutionary diversification and local adaptations in carotenoid metabolism may depend more on the gain or loss of enzymatic reactions than on changes in flux within a network structure.


Assuntos
Evolução Biológica , Tentilhões/metabolismo , Redes e Vias Metabólicas/fisiologia , Animais , Carotenoides/química , Carotenoides/metabolismo , Plumas/metabolismo
16.
J R Coll Physicians Edinb ; 47(4): 310-313, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29537399

RESUMO

Gabapentin and pregabalin prescribing in Scotland has increased substantially over recent years. Evidence suggests that prescribers may be advocating the use of these medicines off-label to avoid prescribing opioid analgesics. The evidence to support gabapentin and pregabalin use in non-neuropathic pain disorders indicates they are less effective than several other licensed non-opioid analgesics. Notably, patients may not benefit from gabapentin and pregabalin but remain at risk of adverse drug reactions. Furthermore, greater availability has resulted in increased diversion of gabapentin and pregabalin; creating problems within the opioid misuse population and prison service. As a consequence, both gabapentin and pregabalin may soon be controlled under the Misuse of Drugs Act 1971. Prescribers should be aware of the very limited clinical evidence for use of gabapentin and pregabalin outside their licensed indications, as well as their capacity to do harm.


Assuntos
Dor Crônica/tratamento farmacológico , Gabapentina/uso terapêutico , Pregabalina/uso terapêutico , Gabapentina/efeitos adversos , Humanos , Prescrição Inadequada , Uso Off-Label , Pregabalina/efeitos adversos , Uso Indevido de Medicamentos sob Prescrição , Medição de Risco
17.
J Physiol ; 594(20): 5735-5748, 2016 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-27104781

RESUMO

Urinary extracellular vesicles (uEVs) are released from all regions of the kidney's nephron and from other cells that line the urinary tract. Extracellular vesicles retain proteomic and transcriptomic markers specific to their cell of origin and so represent a potential reservoir for kidney disease biomarker discovery. Exosomes, a subtype of uEVs, are distinguished from other vesicles by features related to their biogenesis within cells: mature multi-vesicular bodies fuse with the cellular membrane to liberate exosomes into the extracellular space. uEVs represent a novel cell signalling mechanism because they can be shuttled to a recipient cell and, through a number of proposed mechanisms, affect the recipient cell's proteome and function. Here we review the current evidence for uEV signalling along the nephron, their role in health and disease of the kidney, and their potential for clinical translation as biomarkers and therapeutics.


Assuntos
Vesículas Extracelulares/metabolismo , Néfrons/metabolismo , Biomarcadores/metabolismo , Exossomos/metabolismo , Espaço Extracelular/metabolismo , Humanos , Nefropatias , Proteoma/metabolismo , Transcriptoma/fisiologia
18.
J Microsc ; 263(3): 293-9, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26937849

RESUMO

We previously showed that long-lived nanoemulsions, seeming initially vesicular, might be prepared simply by diluting and cooling (quenching) warm microemulsions with n-hexadecane with precooled water. In this paper, we confirm that these systems are vesicular dispersions when fresh, and they can be made with similar structures and compositional dependence using alkanes with chain lengths ranging from octane to hexadecane. The nanostructures of fresh nanoemulsions are imaged with cryogenic transmission electron microscopy (cryo-TEM). We confirm that water-continuous microemulsions give simple dispersions of vesicles (sometimes unilamellar), typically less than 100 nm in diameter; these systems can avoid separation for over 2 months. Selected samples were also prepared using halogenated alkanes to create additional contrast in the cryo-TEM, allowing us to confirm that the oil is located in the observed vesicular structures.

19.
J R Coll Physicians Edinb ; 44(4): 337-43, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25516907

RESUMO

The Scottish Women's Hospitals for Foreign Service were established shortly after the outbreak of the First World War. Opportunities were limited for medical women prior to the war and during it they were unable to obtain a commission in the Royal Army Medical Corps, hence the formation of these voluntary all-women units. The Girton and Newnham Unit, under the leadership of Dr L McIlroy, served with distinction in France, Serbia and Greece, demonstrating clinical competence in the management of the emergency medical and surgical problems associated with warfare, areas usually off-limits to women doctors. They were severely tested but showed endurance and resilience in the running of their hospital in the most difficult of conditions.


Assuntos
Hospitais Filantrópicos/história , Médicas/história , I Guerra Mundial , Europa (Continente) , Feminino , História do Século XX , Humanos , Masculino , Militares/história , Escócia
20.
Lupus ; 23(4): 370-7, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24457602

RESUMO

OBJECTIVE: To determine whether patients with neuropsychiatric (NP) events attributed to systemic lupus erythematosus (SLE) have more global disease activity than patients with NP events not attributed to SLE. METHODS: Patients were recruited from an academic lupus clinic. Global disease activity was measured with the SLE Disease Activity Index 2000 (SLEDAI-2K) and organ damage with the Systemic Lupus International Collaborating Clinics (SLICC)/American College of Rheumatology (ACR) damage index (SDI). NP disease was defined using the ACR case definitions and decision rules for attribution of NP events to SLE and non-SLE causes. RESULTS: There were 68 patients (age (mean ± SD) 40.8 ± 15.2 years, 85% female, 94% Caucasians) with 126 NP events. SLEDAI-2K scores in patients with NP events attributed to SLE were higher than in patients with NP events attributed to non-SLE causes even when NP variables were removed from the SLEDAI-2K (mean ± SD: SLE NP = 7.36 ± 5.42 vs non-SLE NP = 5.53 ± 4.57, P = 0.042). Patients with CNS and diffuse NP events, rather that PNS and focal events, accounted for the group differences in SLEDAI-2K scores. There were no significant differences in total SDI scores comparing NP events due to SLE vs. non-SLE causes (mean ± SD: 2.1 ± 1.8 vs. 1.7 ± 1.7; p = 0.28) even when NP variables were omitted. CONCLUSIONS: Increased global SLE disease activity is associated with concurrent NP events attributed to SLE, particularly for diffuse NP and CNS NP events. The findings have diagnostic and therapeutic implications for SLE patients with NP events and inform pathogenetic mechanisms underlying NPSLE.


Assuntos
Lúpus Eritematoso Sistêmico/fisiopatologia , Vasculite Associada ao Lúpus do Sistema Nervoso Central/fisiopatologia , Transtornos Mentais/fisiopatologia , Adulto , Feminino , Humanos , Lúpus Eritematoso Sistêmico/complicações , Masculino , Transtornos Mentais/etiologia , Pessoa de Meia-Idade , Índice de Gravidade de Doença
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