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2.
Ann Oncol ; 31(7): 930-941, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32289380

RESUMO

BACKGROUND: We have shown previously in multivariable analysis that black men had 19% lower risk of death than white men with metastatic castration-resistant prostate cancer (mCRPC) treated with a docetaxel and prednisone (DP)-based regimen. The primary goal of this analysis was to compare progression-free survival (PFS), biochemical PFS, ≥50% decline in prostate-specific antigen (PSA) from baseline and objective response rate (ORR) in white, black and Asian men with mCRPC treated with a DP-based regimen. PATIENTS AND METHODS: Individual patient data from 8820 mCRPC men randomized on nine phase III trials to a DP-containing regimen were combined. Race used in the analysis was based on self-report. End points were PFS, biochemical PSA, ≥50% decline in PSA from baseline and ORR. The proportional hazards and the logistic regression models were employed to assess the prognostic importance of race in predicting outcomes adjusting for established prognostic factors. RESULTS: Of 8820 patients, 7528 (85%) were white, 500 (6%) were black, 424 were Asian (5%) and 368 (4%) had race unspecified. Median PFS were 8.3 [95% confidence interval (CI) 8.2-8.5], 8.2 (95% CI 7.4-8.8) and 8.3 (95% CI 7.6-8.8) months in white, black and Asian men, respectively. Median PSA PFS were 9.9 (95% CI 9.7-10.4), 8.5 (95% CI 8.0-10.3) and 11.1 (95% CI 9.9-12.5) months in white, black and Asian men, respectively. CONCLUSIONS: We observed no differences in clinical outcomes by race and ethnic groups in men with mCRPC enrolled on these phase III clinical trials with DP.


Assuntos
Neoplasias de Próstata Resistentes à Castração , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Intervalo Livre de Doença , Docetaxel/uso terapêutico , Etnicidade , Humanos , Masculino , Prednisona/uso terapêutico , Antígeno Prostático Específico , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Estudos Retrospectivos , Resultado do Tratamento
3.
J Dairy Sci ; 102(10): 9151-9164, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31326169

RESUMO

The main objective of this study was to determine the association of dry matter intake as percentage of body weight (DMI%BW) and energy balance (EB) prepartum (-21 d relative to parturition) and postpartum (28 d) with ketosis (n = 189) and clinical mastitis (n = 79). For this, DMI%BW and EB were the independent variables and ketosis and clinical mastitis were the dependent variables. A secondary objective was to evaluate prepartum DMI%BW and EB as predictors of ketosis and clinical mastitis. For this, ketosis and clinical mastitis were the independent variables and DMI%BW and EB were the dependent variables. Data from 476 cows from 9 experiments were compiled. Clinical mastitis was diagnosed if milk from 1 or more quarters was abnormal in color, viscosity, or consistency, with or without accompanying heat, pain, redness, or swelling of the quarter or generalized illness, during the first 28 d postpartum. Ketosis was defined as the presence of acetoacetate in urine that resulted in any color change [5 mg/dL (trace) or higher] in the urine test strip (Ketostix, Bayer, Leverkusen, Germany). Cows that developed ketosis had lesser DMI%BW and lesser EB on d -5, -3, -2, and -1 than cows without ketosis. Each 0.1-percentage point decrease in the average DMI%BW and each 1-Mcal decrease in the average of EB in the last 3 d prepartum increased the odds of having ketosis by 8 and 5%, respectively. Cut-offs for DMI%BW and EB during the last 3 d prepartum to predict ketosis were established and were ≤1.5%/d and ≤1.1 Mcal/d, respectively. Cows that developed ketosis had lesser postpartum DMI%BW and EB and greater energy-corrected milk (ECM) than cows without ketosis. Cows that developed clinical mastitis had lesser DMI%BW but similar prepartum EB compared with cows without clinical mastitis. Each 0.1-percentage point decrease in the average DMI%BW and each 1-Mcal decrease in the average EB in the last 3 d prepartum increased the odds of having clinical mastitis by 10 and 8%, respectively. The average DMI%BW and EB during the last 3 d prepartum produced significant cut-offs to predict clinical mastitis postpartum, which were ≤1.2%/d and ≤1.0 Mcal/d, respectively. Cows that developed clinical mastitis had lesser postpartum DMI%BW from d 3 to 15 and on d 17; greater EB on d 18, from d 21 to 23, and on d 26; and lesser ECM. The main limitation in this study is that the time-order of disease relative to DMI%BW and ECM is inconsistent such that postpartum outcomes were measured before and after disease, which was diagnosed at variable intervals after calving. In summary, measures of prepartum DMI were associated with and were predictors of ketosis and clinical mastitis postpartum, although the effect sizes were small.


Assuntos
Dieta/veterinária , Cetose/veterinária , Mastite Bovina/etiologia , Complicações na Gravidez/veterinária , Animais , Peso Corporal , Bovinos , Metabolismo Energético , Feminino , Alemanha , Cetose/etiologia , Lactação , Leite , Parto , Período Pós-Parto , Gravidez , Complicações na Gravidez/etiologia
4.
J Dairy Sci ; 102(10): 9138-9150, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31326177

RESUMO

The main objective of this study was to determine the association of dry matter intake as percentage of body weight (DMI%BW) and energy balance (EB) prepartum (-21 d relative to parturition) and postpartum (28 d) with calving disorders (CDZ; dystocia, twins, and stillbirths; n = 101) and metritis (n = 114). For this, DMI%BW and EB were the independent variables and CDZ and metritis were the dependent variables. A secondary objective was to evaluate prepartum DMI%BW and EB as predictors of CDZ and metritis. For this, CDZ and metritis were the independent variables and DMI%BW and EB were the dependent variables. Data from 476 cows from 9 experiments were compiled. Cows that developed CDZ had lesser postpartum DMI%BW from d 3 to 12 and lesser energy-corrected milk (ECM) than cows that did not develop CDZ. Dry matter intake as percentage of BW and EB prepartum did not affect the odds of CDZ. Cows with metritis had lesser prepartum DMI%BW and EB. Each 0.1-percentage point decrease in the average DMI%BW and each 1-Mcal decrease in the average EB in the last 3 d prepartum increased the odds of having metritis by 8%. The average DMI%BW and EB during the last 3 d prepartum produced significant cut-offs to predict metritis postpartum, which were ≤1.6%/d and ≤2.5 Mcal/d, respectively. Cows that developed metritis had lesser overall postpartum DMI%BW and ECM and lesser EB from d 2 to 5 and from d 7 to 11 than cows that did not develop metritis. The main limitation in this study is that the time-order of disease relative to DMI%BW and ECM is inconsistent such that postpartum outcomes were measured before and after disease, which was diagnosed at variable intervals after calving. In summary, prepartum DMI%BW and EB were associated with and were predictors of metritis although the effect sizes were small for metritis, and calving disorders and metritis were associated with decreased DMI%BW and ECM postpartum.


Assuntos
Doenças dos Bovinos/etiologia , Dieta/veterinária , Complicações na Gravidez/veterinária , Animais , Peso Corporal , Bovinos , Endometrite/etiologia , Endometrite/veterinária , Metabolismo Energético , Feminino , Lactação , Estudos Longitudinais , Leite , Parto , Período Pós-Parto , Gravidez , Complicações na Gravidez/etiologia , Estudos Retrospectivos
5.
J Dairy Sci ; 101(3): 2579-2587, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29331457

RESUMO

The objective of this study was to determine whether the responsiveness of the mammary gland to prolactin (PRL) is affected by the concentration of the hormone. After 1 pre-experimental week (d -7 to -1), 18 Holstein cows in mid to late lactation were injected intramuscularly twice daily with either 0.5 mg of quinagolide (QN) or 2 mL of water (control) for 2 wk (d 1 to 14; treatment period). After the treatment period, all cows received daily subcutaneous injections of 300 mg of domperidone (DOMP) for 3 wk (d 15 to 35; DOMP period). The cows were monitored for an additional 2 wk as a posttreatment period (d 36 to 49). Blood and milk samples were collected 3 times per week. Additionally, blood samples were collected during the a.m. milking on d -4, 14, and 35. Milk production was not affected by QN during the treatment period but was increased during the DOMP and posttreatment periods in the QN cows. With respect to milk composition, the treatments affected only the protein content, which was greater in the QN cows during the treatment period. Blood PRL concentration declined during QN injections and was lower in the QN cows than in the control cows between d 5 and 14. The basal concentration of PRL was increased by DOMP injections during the DOMP and posttreatment periods but was not affected by previous QN injections. Prolactin concentration in milk was not affected by the QN treatments but was increased by DOMP injections during the DOMP and posttreatment periods. Milking-induced PRL release was decreased by QN on d 14. On d 35, milking did not induce a significant release of PRL above the baseline for both treatments. In conclusion, the results of this experiment support the contention that the mammary gland's responsiveness to PRL is modulated by the previous level of the hormone.


Assuntos
Bovinos/fisiologia , Leite/metabolismo , Prolactina/metabolismo , Aminoquinolinas , Animais , Domperidona/administração & dosagem , Agonistas de Dopamina , Antagonistas de Dopamina/administração & dosagem , Feminino , Injeções Intramusculares/veterinária , Injeções Subcutâneas/veterinária , Lactação , Leite/química , Prolactina/sangue
6.
J Dairy Sci ; 101(3): 2588-2601, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29274969

RESUMO

Estradiol inhibits milk production in dairy cows. The present study evaluated the effect of 17ß-estradiol (E2) injections on prolactin (PRL) secretion and the mammary gland response to this hormone. Eight mid-lactation cows were used in a crossover design. During each experimental period, the cows were injected daily with either E2 (2.5 mg) or soy oil (2.5 mL; control) for 7 d. For each period, blood and milk samples were collected from d -4 to 14 (relative to the first injection) to measure PRL, insulin-like growth factor-1, and cortisol concentrations. In addition, blood samples were collected during morning milking on d -4, 2, and 7 to determine the milking-induced PRL release. Mammary gland biopsies were collected on the last day of injections. Milk fat samples were collected from d 1 to 7 and on d 14. The mRNA levels of genes encoding proteins related to mammary activity (α-lactalbumin, ß-casein, and acetyl-coenzyme A carboxylase), apoptosis (Bax, Bcl2, and caspase-3), PRL receptors (PRLR; long and short forms), signal transducer and activator of transcription 5 (STAT5A and STAT5B), and suppressors of cytokine signaling (SOCS2 and SOCS3) were evaluated by real-time reverse transcription PCR using RNA extracted from milk fat and mammary biopsies. Milk production was decreased moderately (about 9%) by E2 injections during the treatment period. Estradiol injections increased basal PRL levels in serum and milk but did not affect milking-induced PRL release. Estradiol injections increased the plasma concentration of insulin-like growth factor-1 but did not affect cortisol concentration during the treatment period. In mammary tissue, the expression of Bcl2 was downregulated, whereas that of STAT5A and B and the Bax:Bcl2 mRNA ratio was higher during E2 injections. The total STAT5 protein content in mammary tissue was elevated by E2 injections. We found no significant difference observed for the other genes in mammary tissue or milk fat. The present data do not support the contention that E2 injections inhibit milk production by interfering with PRL signaling, but enhanced basal PRL concentration and STAT5 gene expression in mammary tissue.


Assuntos
Estradiol/farmacologia , Estrogênios/farmacologia , Expressão Gênica/efeitos dos fármacos , Glândulas Mamárias Animais/efeitos dos fármacos , Leite/metabolismo , Prolactina/sangue , Animais , Bovinos , Estradiol/administração & dosagem , Estrogênios/administração & dosagem , Feminino , Lactação , Glândulas Mamárias Animais/metabolismo
7.
J Dairy Sci ; 99(10): 8443-8450, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27522427

RESUMO

Calves born to cows exposed to heat stress during late gestation (i.e., the dry period) have lower birth weight and weaning weight and compromised passive immune transfer compared with those born to dams that are cooled. However, it is unknown if heat stress in utero has carryover effects after weaning. The objective was to evaluate the effect of heat stress (HT) or cooling (CL) in late gestation dairy cows on the survival, growth, fertility, and milk production in the first lactation of their calves. Data of animals obtained from previous experiments conducted during 5 consecutive summers in Florida were pooled and analyzed. Cows were dried off 46d before expected calving and randomly assigned to 1 of 2 treatments, HT or CL. Cooled cows were housed with sprinklers, fans, and shade, whereas only shade was provided to HT cows. Within 4h of birth, 3.8 L of colostrum was fed to calves from both groups of cows. All calves were managed in the same manner and weaned at 49d of age. Birth weight and survival of 146 calves (HT=74; CL=72) were analyzed. Additionally, body weight, growth rate, fertility, and milk production in the first lactation from 72 heifers (HT=34; CL=38) were analyzed. As expected, HT calves were lighter (means ± SEM; 39.1±0.7 vs. 44.8±0.7kg) at birth than CL calves. Cooled heifers were heavier up to 1yr of age, but had similar total weight gain (means ± SEM; 305.8±6.3 vs. 299.1±6.3kg, respectively) compared with HT heifers. No effect of treatment was observed on age at first insemination (AI) and age at first parturition. Compared with CL heifers, HT heifers had a greater number of services per pregnancy confirmed at d 30 after AI, but no treatment effect was observed on number of services per pregnancy confirmed at d 50 after AI. A greater percentage of CL heifers reached first lactation compared with HT heifers (85.4 vs. 65.9%). Moreover, HT heifers produced less milk up to 35wk of the first lactation compared with CL heifers (means ± SEM; 26.8±1.7 vs. 31.9±1.7kg/d), and no difference in body weight during lactation was observed (means ± SEM; HT: 568.4±14.3kg; CL: 566.5±14.3kg). These data suggest that heat stress during the last 6wk of gestation induces a phenotype that negatively affects survival and milk production up to and through the first lactation of offspring.


Assuntos
Doenças dos Bovinos/fisiopatologia , Transtornos de Estresse por Calor/veterinária , Temperatura Alta , Lactação , Estresse Fisiológico , Animais , Bovinos , Colostro/química , Gorduras na Dieta/análise , Feminino , Fertilidade , Florida , Lactose/análise , Leite/química , Leite/metabolismo , Proteínas do Leite/análise , Gravidez , Complicações na Gravidez/veterinária , Desmame , Aumento de Peso
8.
Prostate Cancer Prostatic Dis ; 19(4): 390-394, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27431498

RESUMO

BACKGROUND: Obesity is a risk factor for incident prostate cancer (PC) as well as risk of disease progression and mortality. We hypothesized that men diagnosed with lower-risk PC and who elected active surveillance (AS) for their cancer management would likely initiate lifestyle changes that lead to weight loss. METHODS: Patients were enrolled in the Prostate Active Surveillance Study (PASS), a multicenter prospective biomarker discovery and validation study of men who have chosen AS for their PC. Data from 442 men diagnosed with PC within 1 year of study entry who completed a standard of care 12-month follow-up visit were analyzed. We examined the change in weight and body mass index (BMI) over the first year of study participation. RESULTS: After 1 year on AS, 7.5% (33/442) of patients had lost 5% or more of their on-study weight. The proportion of men who lost 5% or more weight was similar across categories of baseline BMI: normal/underweight (8%), overweight (6%) and obese (10%, χ2 test P=0.44). The results were similar for patients enrolled in the study 1 year or 6 months after diagnosis. By contrast, after 1 year, 7.7% (34/442) of patients had gained >5% of their weight. CONCLUSIONS: Only 7.5% of men with low-risk PC enrolled in AS lost a modest (⩾5%) amount of weight after diagnosis. Given that obesity is related to PC progression and mortality, targeted lifestyle interventions may be effective at this 'teachable moment', as men begin AS for low-risk PC.


Assuntos
Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/patologia , Redução de Peso/fisiologia , Idoso , Índice de Massa Corporal , Peso Corporal/fisiologia , Progressão da Doença , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Obesidade/patologia , Estudos Prospectivos , Fatores de Risco
9.
Prostate Cancer Prostatic Dis ; 19(3): 264-70, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27136741

RESUMO

BACKGROUND: Expanding interest in and use of active surveillance for early state prostate cancer (PC) has increased need for prognostic biomarkers. Using a multi-institutional tissue microarray resource including over 1000 radical prostatectomy samples, we sought to correlate Ki67 expression captured by an automated image analysis system with clinicopathological features and validate its utility as a clinical grade test in predicting cancer-specific outcomes. METHODS: After immunostaining, the Ki67 proliferation index (PI) of tumor areas of each core (three cancer cores/case) was analyzed using a nuclear quantification algorithm (Aperio). We assessed whether Ki67 PI was associated with clinicopathological factors and recurrence-free survival (RFS) including biochemical recurrence, metastasis or PC death (7-year median follow-up). RESULTS: In 1004 PCs (∼4000 tissue cores) Ki67 PI showed significantly higher inter-tumor (0.68) than intra-tumor variation (0.39). Ki67 PI was associated with stage (P<0.0001), seminal vesicle invasion (SVI, P=0.02), extracapsular extension (ECE, P<0.0001) and Gleason score (GS, P<0.0001). Ki67 PI as a continuous variable significantly correlated with recurrence-free, overall and disease-specific survival by multivariable Cox proportional hazard model (hazards ratio (HR)=1.04-1.1, P=0.02-0.0008). High Ki67 score (defined as ⩾5%) was significantly associated with worse RFS (HR=1.47, P=0.0007) and worse overall survival (HR=2.03, P=0.03). CONCLUSIONS: In localized PC treated by radical prostatectomy, higher Ki67 PI assessed using a clinical grade automated algorithm is strongly associated with a higher GS, stage, SVI and ECE and greater probability of recurrence.


Assuntos
Antígeno Ki-67/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/mortalidade , Proliferação de Células , Humanos , Estimativa de Kaplan-Meier , Masculino , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Antígeno Prostático Específico , Prostatectomia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Recidiva , Análise Serial de Tecidos
10.
Prostate Cancer Prostatic Dis ; 18(3): 264-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25939516

RESUMO

BACKGROUND: Biopsies performed for elevated serum PSA often show inflammatory infiltrates. However, the influence of intraprostatic inflammation on serum PSA in men without biopsy indication and negative for prostate cancer has not been described in detail. METHODS: We studied 224 men in the placebo arm of the Prostate Cancer Prevention Trial (PCPT) who underwent end-of-study biopsy per trial protocol, had PSA <4 ng ml(-1), normal digital rectal examination and a biopsy negative for cancer. We analyzed data from hematoxylin and eosin-stained slides containing a mean of three biopsy cores. Inflammation measures included the extent (percentage of tissue area with inflammation) and intensity (product of scores for extent and grade) of total, acute and chronic inflammation in the entire tissue area examined, and by tissue compartment. We calculated median measures of inflammation by prebiopsy serum PSA tertile (>0 to ≤0.8, >0.8 to ≤1.5 and >1.5 to <4.0 ng ml(-1)). We estimated the association between percentage of tissue area with inflammation and natural logarithm of PSA using linear regression adjusting for age at biopsy. RESULTS: Median percentage of tissue area with inflammation increased from 2 to 5 to 9.5% across PSA tertiles (P-trend <0.0001). For every 5% increase in tissue area with inflammation, log PSA increased by 0.061 ng ml(-1) (P=0.0002). Median extent and intensity scores increased across PSA tertiles in luminal and intraepithelial compartments for acute inflammation and in stromal and intraepithelial compartments for chronic inflammation (all P-trend ≤0.05). CONCLUSIONS: In men without clinical suspicion of prostate cancer, greater overall inflammation, luminal and intraepithelial acute inflammation and stromal and intraepithelial chronic inflammation were associated with higher serum PSA.


Assuntos
Inflamação/patologia , Antígeno Prostático Específico/sangue , Próstata/patologia , Neoplasias da Próstata/sangue , Neoplasias da Próstata/patologia , Idoso , Idoso de 80 Anos ou mais , Biópsia , Estudos de Casos e Controles , Estudos Transversais , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
11.
J Dairy Sci ; 97(12): 7426-36, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25459905

RESUMO

Heat stress in the dry period affects the immune status of dairy cows in the subsequent lactation. We hypothesized that cooling during the dry period improves immune response to postpartum intramammary infection (IMI) by environmental pathogens such as Streptococcus uberis. Cows were dried off 46 d before expected calving and assigned to cooling (CL, n = 15) or heat stress (HT, n = 15). Cooled cows were housed with sprinklers, fans, and shade, whereas the HT group had only shade. All cows were cooled postpartum. Rectal temperature (RT) and respiration rate (RR) were recorded thrice weekly during the dry period. From −46 to 42 d relative to calving, dry matter intake was recorded daily, and both body weight (BW) and body condition score (BCS) weekly. Milk yield and composition were recorded daily after calving. Streptococcus uberis IMI was induced at 5 d postpartum in a subset of cows (CL, n = 5; HT, n = 5). Blood was collected at 0, 12, 18, 24, and 36 h after IMI. Hematological analysis was performed, and neutrophils isolated for RNA extraction. Immune response genes (TLR2, IL1-ß, IL6, IL8, IL10, and TNFα) were assessed by real-time, reverse transcription-PCR. Relative to HT cows, CL cows had lower RT and RR during the dry period. The CL cows also consumed more feed prepartum but not postpartum, gained more BW prepartum but lost more BW in lactation, and had higher BCS score prepartum and a lower BCS postpartum. During 40 wk of lactation, CL cows produced more milk (33.8 vs. 30.0 kg/d) than HT cows but milk composition was not affected. Cows in the CL group had greater white blood cell counts and more neutrophils than HT cows during IMI. From 0 to 36 h post-IMI, TNFα mRNA expression decreased, whereas that of IL6 and IL8 increased in both treatments. Additionally, CL cows had lower IL10 mRNA expression at 18 h post-IMI. Expression of TLR2 mRNA decreased over time in both treatments. However, CL cows had greater overall TLR2 mRNA expression than HT. No differences were detected for mRNA expression of IL1-ß, IL6, IL8, or TNFα. Cooling cows during the dry period alters immune function and neutrophil response to IMI in early lactation.


Assuntos
Lactação/fisiologia , Mastite Bovina/microbiologia , Leite/metabolismo , Infecções Estreptocócicas/veterinária , Streptococcus/fisiologia , Animais , Peso Corporal , Bovinos , Citocinas/genética , Indústria de Laticínios/métodos , Feminino , Regulação Bacteriana da Expressão Gênica , Temperatura Alta , Glândulas Mamárias Animais/microbiologia , Mastite Bovina/imunologia , Neutrófilos/imunologia , Neutrófilos/metabolismo , Período Pós-Parto , Infecções Estreptocócicas/imunologia , Infecções Estreptocócicas/microbiologia , Streptococcus/classificação , Estresse Fisiológico
12.
J Dairy Sci ; 97(10): 6426-39, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25108869

RESUMO

Calves born to cows exposed to heat stress during the dry period and fed their dams' colostrum have compromised passive and cell-mediated immunity compared with calves born to cows cooled during heat stress. However, it is unknown if this compromised immune response is caused by calf or colostrum intrinsic factors. Two studies were designed to elucidate the effects of colostrum from those innate to the calf. The objective of the first study was to evaluate the effect of maternal heat stress during the dry period on calf-specific factors related to immune response and growth performance. Cows were dried off 46 d before expected calving and randomly assigned to 1 of 2 treatments: heat stress (HT; n=18) or cooling (CL; n=18). Cows of the CL group were housed with sprinklers, fans and shade, whereas cows of HT group had only shade. After calving, the cows were milked and their colostrum was frozen for the subsequent study. Colostrum from cows exposed to a thermoneutral environment during the dry period was pooled and stored frozen (-20 °C). Within 4h of birth, 3.8L of the pooled colostrum from thermoneutral cows was fed to calves born to both HT and CL cows. Day of birth was considered study d 0. All calves were exposed to the same management and weaned at d 49. Blood samples were collected before colostrum feeding, 24h after birth and twice weekly up to d 28. Total serum IgG concentrations were determined. Body weight was recorded at birth and at d 15, 30, 45, and 60. Relative to CL calves, HT calves were lighter at birth (38.3 vs. 43.1 kg), but no difference in weight gain was observed at d 60. Additionally, HT calves had lower apparent efficiency of IgG absorption (26.0 vs. 30.2%), but no differences were observed for total IgG concentration. The objective of the second study was to evaluate the isolated effect of the colostrum from HT cows on calf immune response and growth performance. The experimental design was identical to the first study, but all calves were born to cows under thermoneutral conditions during the dry period. At birth, calves were blocked by sex and birth weight and then randomly assigned to 1 of 2 treatments, which meant they received pooled colostrum from HT cows or CL cows. No treatment effect was observed on passive immune transfer or on postnatal growth. Thus, heat stress during the last 6 wk of gestation negatively affects the ability of the calf to acquire passive immunity, regardless of colostrum source.


Assuntos
Animais Recém-Nascidos/crescimento & desenvolvimento , Doenças dos Bovinos/fisiopatologia , Colostro/imunologia , Transtornos de Estresse por Calor/veterinária , Imunoglobulina G/análise , Complicações na Gravidez/veterinária , Animais , Animais Recém-Nascidos/imunologia , Peso ao Nascer , Bovinos , Doenças dos Bovinos/imunologia , Feminino , Transtornos de Estresse por Calor/imunologia , Transtornos de Estresse por Calor/fisiopatologia , Hidrocortisona/sangue , Imunidade Celular/imunologia , Imunoglobulina G/sangue , Masculino , Leite/imunologia , Gravidez , Complicações na Gravidez/imunologia , Complicações na Gravidez/fisiopatologia
13.
J Anim Sci ; 91(1): 168-73, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23100573

RESUMO

Environmental factors, such as photoperiod and heat stress, can be manipulated during the dry period to influence health, productivity, and reproductive performance of dairy cows in their subsequent lactation. The impacts of photoperiod and heat stress on subsequent lactation are related to alterations in prolactin (PRL) signaling and may affect the expression of pregnancy-specific protein B (PSPB). Additionally, exposure of cows to heat stress during the dry period decreases gestation length; however, the mechanism involved in this process is unknown. The objective of these experiments was to evaluate the influence of environmental factors (i.e., heat stress and photoperiod) during late gestation (i.e., dry period) on PSPB concentrations in plasma of dairy cows. In Exp. 1, cows were dried off in the summer months approximately 46 d before expected calving and assigned randomly to heat stress (HT; n=30) or cooling (CL; n=30) treatment. Cooling cows were housed with sprinklers, fans, and shade, whereas HT cows were provided only shade. In Exp. 2, cows were dried off at approximately 60 d before expected calving in summer/fall months and randomly assigned to 3 treatments: long day photoperiod (LDPP: 16L:8D; n=15), short day photoperiod (SDPP: 8L:16D; n=14) and SDPP+PRL implant (12 mg/d of PRL at 28 d or 16 mg/d of PRL at 39 d; n=11). In both experiments, plasma samples were collected at dry off and at -32, -18, -7, -3 and 0 d relative to calving. In Exp. 1, greater concentrations of PSPB were detected in plasma of CL versus HT cows (388.3±24.7 vs. 287.4±23.8 ng/mL; P<0.01). Concentrations of PSPB did not differ between -46 to -18 d before calving (66.0 ng/mL). However, PSPB concentrations were greater (P<0.01) for CL cows at d -7 (534.7>357.2 ng/mL), -3 (807.2>572.2 ng/mL) and 0 (800.8>563.5 ng/mL) relative to calving. Additionally, HT cows in Exp. 1 had increased PRL plasma concentrations compared with CL cows (21.01±1.6 vs. 13.78±1.6 ng/mL). In Exp. 2, no differences were detected in plasma concentrations of PSPB (ng/mL) among LDPP, SDPP, or SDPP+PRL groups on d -60 (41.5), -32 (51.7), -18 (58.5), -7 (532.9), -3 (838.2), and 0 (729.4) relative to parturition. Photoperiodic PRL concentrations were 10.81, 7.84, and 4.22 ng/mL for LDPP, SDPP+ PRL, and SDPP, respectively. Results indicate that HT alters PSPB concentrations in late pregnancy, suggesting that placental activity is altered in cows exposed to excessive elevated temperatures around the time of calving. However, the mechanism involved likely is not associated with changes in PRL secretion.


Assuntos
Bovinos/metabolismo , Proteínas da Gravidez/metabolismo , Prenhez , Animais , Temperatura Corporal , Indústria de Laticínios , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Gravidez , Proteínas da Gravidez/sangue , Proteínas da Gravidez/genética , Prenhez/fisiologia , Prolactina/genética , Prolactina/metabolismo , Respiração
14.
J Dairy Sci ; 96(1): 378-83, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23141830

RESUMO

Heat stress (HT) during the dry period compromises mammary gland development, decreases future milk production, and impairs the immune status of dairy cows. Our objective was to evaluate the effect of cooling HT cows during the dry period on gene expression of the mammary gland and peripheral blood mononuclear cells (PBMC). Cows were dried off 46 d before their expected calving and assigned to 2 treatments, HT or cooling (CL). Cows in the CL group were cooled with sprinklers and fans whereas HT cows were not. After parturition, all cows were housed in a freestall barn with cooling. The PBMC were isolated at dry-off and at -20, 2, and 20 d relative to calving from a subset of cows (HT, n=9; CL, n=10), and mammary biopsies were taken at the same intervals (HT, n=7; CL, n=6) for RNA extraction. Gene expression was assessed using a custom multiplex gene expression assay based on traditional reverse transcription-PCR. Genes involved in prolactin (PRL) signaling [PRL receptor long form, PRL receptor short form, suppressor of cytokine signaling (SOCS)2, SOCS3, IGF2, IGF binding protein 5, and cyclin D1], fatty acid metabolism (acetyl-CoA carboxylase α (ACACA) and lipoprotein lipase (LPL)], and IGF1 were evaluated in mammary tissue, and genes related to fatty acid metabolism [ACACA, fatty acid synthase (FASN), and LPL], cytokine production [IL6, IL8, and tumor necrosis factor (TNF)], and IGF1 were evaluated in PBMC. No differences were observed in PRL signaling or fatty acid metabolism gene expression in the mammary gland. In PBMC, HT cows had greater mRNA expression of IGF1 and TNF during the transition period relative to CL and upregulated IL8 and downregulated FASN mRNA expression at 2 d relative to calving. We conclude that cooling HT cows during the dry period alters expression of genes involved in cytokine production and lipid metabolism in PBMC.


Assuntos
Bovinos/fisiologia , Resposta ao Choque Térmico/fisiologia , Leucócitos Mononucleares/metabolismo , Glândulas Mamárias Animais/metabolismo , Animais , Bovinos/metabolismo , Feminino , Expressão Gênica/fisiologia , Perfilação da Expressão Gênica/veterinária , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária
15.
J Dairy Sci ; 95(12): 7128-36, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23021751

RESUMO

Heat stress during the dry period affects the cow's mammary gland development, metabolism, and immunity during the transition period. However, the effect of late-gestation heat stress on calf performance and immune status is unknown. Our objective was to evaluate the effect of heat stress during the final ~45 d of gestation on growth and immune function of calves. Calves (17/treatment) were born to cows that were exposed to cooling (CL) or heat stress (HT) during the dry period. Only heifer calves (CL, n=12; HT, n=9) were used in measurements of growth and immune status after birth. Heifer calves were managed under identical conditions. All were fed 3.78 L of colostrum from their respective dams within 4 h of birth and were weaned at 2 mo of age (MOA). Body weight (BW) was obtained at weaning and then monthly until 7 MOA. Withers height (WH) was measured monthly from 3 to 7 MOA. Hematocrit and plasma total protein were assessed at birth, 1, 4, 7, 11, 14, 18, 21, 25, and 28 d of age. Total serum IgG was evaluated at 1, 4, 7, 11, 14, 18, 21, 25, and 28 d of age, and apparent efficiency of absorption was calculated. Peripheral blood mononuclear cells were isolated at 7, 28, 42, and 56 d of age, and proliferation rate was measured by (3)H-thymidine incorporation in vitro. Blood cortisol concentration was measured in the dams during the dry period and in calves in the preweaning period. Gestation length was 4d shorter for HT cows compared with CL cows. Calves from CL cows had greater BW than calves from HT cows at birth (42.5 vs. 36.5 kg). Compared with CL heifers, HT heifers had decreased weaning BW (78.5 vs. 65.9 kg) but similar BW (154.6 vs. 146.4 kg) and WH (104.8 vs. 103.4 cm) from 3 to 7 MOA. Compared with CL, heifers from HT cows had less total plasma protein (6.3 vs. 5.9 g/dL), total serum IgG (1,577.3 vs. 1,057.8 mg/dL), and apparent efficiency of absorption (33.6 vs. 19.2%), and tended to have decreased hematocrit (33 vs. 30%). Additionally, CL heifers had greater peripheral blood mononuclear cell proliferation relative to HT heifers (23.8 vs. 14.1 fold). Compared with CL, late-gestation HT did not affect the blood cortisol concentration of dams during the dry period or that of the calves in the preweaning period, but CL calves tended to have increased circulating cortisol at birth (7.6 vs. 5.7 µg/dL). We conclude that heat stress of the dam during the dry period compromises the fetal growth and immune function of offspring from birth through weaning.


Assuntos
Animais Recém-Nascidos/crescimento & desenvolvimento , Bovinos/crescimento & desenvolvimento , Transtornos de Estresse por Calor/veterinária , Animais , Animais Recém-Nascidos/imunologia , Proteínas Sanguíneas/análise , Bovinos/imunologia , Feminino , Idade Gestacional , Transtornos de Estresse por Calor/fisiopatologia , Hematócrito/veterinária , Hidrocortisona/sangue , Imunidade Celular/fisiologia , Leucócitos Mononucleares/fisiologia , Gravidez
16.
J Dairy Sci ; 95(10): 5645-56, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22863093

RESUMO

Objectives were to characterize postpartum metabolic and hormonal differences between nonlactating and lactating dairy cows, evaluate lactation and pregnancy effects on endometrium and conceptus expression of selected genes, and characterize associations between conceptus and endometrial expression of genes in early pregnancy (d 17). Pregnant heifers were assigned randomly after calving to a lactating group (L, n=17) and a nonlactating group (NL, n=16). The L cows were fed a total mixed ration [1.65 Mcal of net energy for lactation (NE(L))/kg, 16.5% crude protein (CP)] ad libitum, and the NL cows were fed a maintenance ration (1.45 Mcal of NE(L)/kg, 12.2% CP) once per day. All cows were presynchronized and enrolled in a timed artificial insemination (TAI) protocol; 10 cows in the L and 12 in the NL received TAI. On d 17 after GnRH and TAI, cows were slaughtered and endometrial and conceptus tissues collected. The Affymetrix Bovine Genome DNA Microarray (Affymetrix Inc., Santa Clara, CA) was used to assess conceptus and endometrial gene expression. The L cows had higher body temperature than the NL cows (38.4 vs. 38.2°C), and the NL cows cycled earlier than the L cows (26.3 vs. 34.7 d in milk). Cows in the L group had greater plasma concentrations of ß-hydroxybutyrate (4.90 vs. 2.97 mg/dL) and blood urea N (11.6 vs. 6.5mg/dL) and lower concentrations of glucose (74.0 vs. 79.9 mg/dL) compared with NL cows. Insulin-like growth factor-1 was lower for L compared with NL (140.5 vs. 198.2 ng/mL) and was greater for cows subsequently classified pregnant compared with cyclic (191.0 vs. 147.6 ng/mL). The concentration of progesterone from GnRH or TAI (d 0) until d 17 was lower for L cows than for NL cows. Gene expression analyses indicated that all conceptuses (n=13) expressed pregnancy-associated glycoprotein (PAG) genes PAG2, PAG8, PAG11, and PAG12. The same PAG family genes were observed in the endometrium of some pregnant cows. Simple and standard partial correlation analyses detected associations of conceptus PAG11 with prostaglandin regulatory genes. In conclusion, lactation altered metabolic status, delayed initiation of cyclicity, and decreased concentrations of progesterone in pregnant cows. Early expression of PAG genes in the conceptus may contribute to successful development of early pregnancy and possibly alter mechanisms related with embryo survival such as prostaglandin synthesis.


Assuntos
Bovinos/fisiologia , Endométrio/metabolismo , Regulação da Expressão Gênica/fisiologia , Lactação/fisiologia , Prenhez/fisiologia , Ácido 3-Hidroxibutírico/sangue , Animais , Glicemia/análise , Nitrogênio da Ureia Sanguínea , Bovinos/genética , Bovinos/metabolismo , Endométrio/fisiologia , Ácidos Graxos não Esterificados/sangue , Feminino , Regulação da Expressão Gênica/genética , Hormônio Liberador de Gonadotropina/sangue , Fator de Crescimento Insulin-Like I/análise , Lactação/genética , Lactação/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos/veterinária , Período Pós-Parto/metabolismo , Período Pós-Parto/fisiologia , Gravidez , Proteínas da Gravidez/sangue , Prenhez/genética , Prenhez/metabolismo , Progesterona/sangue
17.
J Dairy Sci ; 95(10): 5657-75, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22884349

RESUMO

Objectives were to determine effects of lactation and pregnancy on endometrial gene expression on d 17 of the estrous cycle and pregnancy. Heifers (n=33) were assigned randomly after parturition to lactating (L, n=17) or nonlactating (NL, n=16) groups. Cows were subjected to an ovulation synchronization program for a timed artificial insemination (TAI); 10 cows in L and 12 in NL were inseminated. Slaughter occurred 17 d after the day equivalent to TAI, and intercaruncular endometrial tissues were collected. Gene expression was determined by DNA microarray analysis for pregnant (L, n=8; NL, n=6) and noninseminated cyclic (L, n=7; NL, n=4) cows. Differentially expressed genes were selected with a P-value <0.01 and absolute expression >40. In addition, a fold effect >1.5 was used as a criterion for genes affected by pregnancy. In total, 210 genes were differentially regulated by lactation (136 downregulated and 74 upregulated), and 702 genes were differentially regulated by pregnancy (407 downregulated and 295 upregulated). The interaction effect of pregnancy and lactation affected 61 genes. Genes up- and downregulated in pregnant cows were associated with several gene ontology terms, such as defense response and interferon regulatory factor, cell adhesion, and extracellular matrix. The gene ontology analyses of up- and downregulated genes of lactating cows revealed terms related to immunoglobulin-like fold, immune response, COMM domain, and non-membrane-bounded organelle. Several genes upregulated by lactation, such as IGHG1, IGLL1, IGK, and TRD, were related to immune function, particularly for B cells and γδ T cells. Developmental genes related to limb and neural development and glucose homeostasis (e.g., DKK1, RELN, PDK4) were downregulated by lactation, whereas an interaction was also detected for RELN. The stated genes associated with immune function and developmental genes expressed in the endometrium affected by lactational state are possible candidate genes for interventions to improve fertility of lactating dairy cows.


Assuntos
Bovinos/fisiologia , Endométrio/fisiologia , Ciclo Estral/fisiologia , Regulação da Expressão Gênica/fisiologia , Lactação/fisiologia , Prenhez/fisiologia , Animais , Bovinos/genética , Endométrio/metabolismo , Ciclo Estral/genética , Sincronização do Estro/genética , Sincronização do Estro/fisiologia , Feminino , Regulação da Expressão Gênica/genética , Inseminação Artificial/veterinária , Lactação/genética , Análise de Sequência com Séries de Oligonucleotídeos , Gravidez , Prenhez/genética , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária
18.
J Dairy Sci ; 95(9): 5035-5046, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22916907

RESUMO

Heat stress (HT) during the dry period affects hepatic gene expression and adipose tissue mobilization during the transition period. In addition, it is postulated that HT may alter insulin action on peripheral tissues. Our objective was to evaluate the effect of cooling heat-stressed cows during the dry period on insulin effects on peripheral tissues during the transition period. Cows were dried off 46 d before expected calving and assigned to 1 of 2 treatments: HT (n = 16) or cooling (CL, n = 16). During the dry period, the average temperature-humidity index was 78, but CL cows were cooled with sprinklers and fans, whereas HT cows were not. After calving, all cows were housed and managed under the same conditions. Rectal temperatures were measured twice daily (0730 and 1430 h) and respiration rate recorded 3 times weekly during the dry period. Dry matter intake was recorded daily from dry-off to 42 d relative to calving (DRC). Body weight and body condition score were measured weekly from dry-off to 42 DRC. Milk yield and composition were recorded daily to 42 wk postpartum. Glucose tolerance tests (GTT) and insulin challenges (IC) were performed at dry-off, -14, 7, and 28 DRC in a subset of cows (HT, n = 8; CL, n = 8). Relative to HT, CL cows had lower rectal temperatures (39.3 vs. 39.0°C) in the afternoon and respiration rate (69 vs. 48 breath/min). Cows from the cooling treatment tended to consume more feed than HT cows prepartum and postpartum. Compared with HT, CL cows gained more weight before calving but lost more weight and body condition in early lactation. Cows from the cooling treatment produced more milk than HT cows (34.0 vs. 27.7 kg/d), but treatments did not affect milk composition. Treatments did not affect circulating insulin and metabolites prepartum, but CL cows had decreased glucose, increased nonesterified fatty acid, and tended to have lower insulin concentrations in plasma postpartum compared with HT cows. Cooling prepartum HT cows did not affect the insulin responses to GTT and IC during the transition period and glucose responses to GTT and IC at -14 and 28 DRC were not affected by treatments. At 7 DRC, CL cows tended to have slower glucose clearance to GTT and weaker glucose response to IC relative to HT cows. Cows from the cooling treatment had stronger nonesterified fatty acid responses to IC postpartum but not prepartum compared with HT. In conclusion, cooling heat-stressed dairy cows in the dry period reduced insulin effects on peripheral tissues in early lactation but not in the dry period.


Assuntos
Doenças dos Bovinos/terapia , Crioterapia/veterinária , Transtornos de Estresse por Calor/veterinária , Insulina/fisiologia , Animais , Glicemia/fisiologia , Temperatura Corporal/fisiologia , Bovinos , Doenças dos Bovinos/fisiopatologia , Feminino , Teste de Tolerância a Glucose/veterinária , Transtornos de Estresse por Calor/fisiopatologia , Transtornos de Estresse por Calor/terapia , Temperatura Alta/efeitos adversos , Umidade/efeitos adversos , Insulina/sangue , Lactação/fisiologia , Gravidez , Taxa Respiratória/fisiologia
19.
J Anim Sci ; 90(3): 755-60, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21984715

RESUMO

Photoperiod, or the daily sequence of light and dark, has dramatic effects on many physiological systems across animal species. Light patterns alter melatonin secretion profiles and, subsequently, the release profiles and circulating concentrations of several hormones that influence a variety of physiological responses. Although the impact of photoperiod on reproductive processes is perhaps the most common example, it is often the seasonal aspects of ovulation and anestrus that are considered. However, in cattle, the final phase of reproduction, that is, lactation, is significantly influenced by photoperiod. In contrast to short days (SDPP; 8 h light:16 h dark), exposure to long days (LDPP) of 16 to 18 h of light and 6 to 8 h of darkness increases milk yield 2 to 3 kg/d, regardless of the stage of lactation. There is evidence that this LDPP effect is due to increased circulating IGF-I, independent of any effect on GH concentrations. Cows that are housed under SDPP during the dry period have increased mammary growth and produce 3 to 4 kg/d more milk in the subsequent lactation compared with cows on LDPP when dry. While cows are on SDPP, circulating prolactin (PRL) diminishes but expression of PRL receptor increases in mammary, liver, and immune cells. Moreover, PRL signaling pathways within those tissues are affected by photoperiod. Further, replacement of PRL to cows on SDPP partially reverses the effects of SDPP on production in the next lactation. Thus, effects on dry cows are mediated through a PRL-dependent pathway. Before maturity, LDPP improve mammary parenchymal accumulation and lean body growth, which lead to greater yields in the first lactation. The accumulated evidence supports the concept that photoperiod manipulation can be harnessed to improve the efficiency of production across the life cycle of the dairy cow.


Assuntos
Bovinos/fisiologia , Lactação/fisiologia , Glândulas Mamárias Animais/fisiologia , Fotoperíodo , Animais , Relógios Biológicos , Feminino , Gravidez , Reprodução/fisiologia
20.
Prostate Cancer Prostatic Dis ; 15(2): 170-6, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21912428

RESUMO

BACKGROUND: BPH and lower urinary tract symptoms (LUTS) are very common among older men in Western countries. However, the prevalence of these two conditions in the developing countries is less clear. METHODS: We assessed the age-standardized prevalence of BPH and/or LUTS among West Africans in a probability sample of 950 men aged 50-74 in Accra, Ghana, with no evidence of biopsy-confirmed prostate cancer after screening with PSA and digital rectal examination (DRE). Information on LUTS was based on self-reports of the International Prostate Symptom Score (IPSS). BPH was estimated using DRE, PSA levels and imputed prostate volume. RESULTS: The prevalence of DRE-detected enlarged prostate was 62.3%, while that of PSA≥1.5 ng ml(-1) (an estimate of prostate volume ≥ 30 cm(3)) was 35.3%. The prevalence of moderate-to-severe LUTS (IPSS≥8) was 19.9%. The prevalence of IPSS≥8 and an enlarged prostate on DRE was 13.3%. Although there is no universally agreed-upon definition of BPH/LUTS, making comparisons across populations difficult, BPH and/or LUTS appear to be quite common among older Ghanaian men. CONCLUSIONS: We found that after age standardization, the prevalence of DRE-detected enlarged prostate in Ghanaian men is higher than previously reported for American men, but the prevalence of LUTS was lower than previously reported for African Americans. Further studies are needed to confirm these findings and identify the risk factors for BPH in both Africans and African Americans.


Assuntos
Sintomas do Trato Urinário Inferior/epidemiologia , Hiperplasia Prostática/epidemiologia , Negro ou Afro-Americano , Idoso , População Negra , Exame Retal Digital , Gana/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Autorrelato
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