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1.
J Dairy Sci ; 107(6): 3700-3715, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38135043

RESUMO

Reproductive performance is a key determinant of cow longevity in a pasture-based, seasonal dairy system. Unfortunately, direct fertility phenotypes such as intercalving interval or pregnancy rate tend to have low heritabilities and occur relatively late in an animal's life. In contrast, age at puberty (AGEP) is a moderately heritable, early-in-life trait that may be estimated using an animal's age at first measured elevation in blood plasma progesterone (AGEP4) concentrations. Understanding the genetic architecture of AGEP4 in addition to genetic relationships between AGEP4 and fertility traits in lactating cows is important, as is its relationship with body size in the growing animal. Thus, the objectives of this research were 3-fold. First, to estimate the genetic and phenotypic (co)variances between AGEP4 and subsequent fertility during first and second lactations. Second, to quantify the associations between AGEP4 and height, length, and BW measured when animals were approximately 11 mo old (standard deviation = 0.5). Third, to identify genomic regions that are likely to be associated with variation in AGEP4. We measured AGEP4, height, length, and BW in approximately 5,000 Holstein-Friesian or Holstein-Friesian × Jersey crossbred yearling heifers across 54 pasture-based herds managed in seasonal calving farm systems. We also obtained calving rate (CR42, success or failure to calve within the first 42 d of the seasonal calving period), breeding rate (PB21, success or failure to be presented for breeding within the first 21 d of the seasonal breeding period) and pregnancy rate (PR42, success or failure to become pregnant within the first 42 d of the seasonal breeding period) phenotypes from their first and second lactations. The animals were genotyped using the Weatherby's Versa 50K SNP array (Illumina, San Diego, CA). The estimated heritabilities of AGEP4, height, length, and BW were 0.34 (90% credibility interval [CRI]: 0.30, 0.37), 0.28 (90% CRI: 0.25, 0.31), 0.21 (90% CRI: 0.18, 0.23), and 0.33 (90% CRI: 0.30, 0.36), respectively. In contrast, the heritabilities of CR42, PB21 and PR42 were all <0.05 in both first and second lactations. The genetic correlations between AGEP4 and these fertility traits were generally moderate, ranging from 0.11 to 0.60, whereas genetic correlations between AGEP4 and yearling body-conformation traits ranged from 0.02 to 0.28. Our GWAS highlighted a genomic window on chromosome 5 that was strongly associated with variation in AGEP4. We also identified 4 regions, located on chromosomes 14, 6, 1, and 11 (in order of decreasing importance), that exhibited suggestive associations with AGEP4. Our results show that AGEP4 is a reasonable predictor of estimated breeding values for fertility traits in lactating cows. Although the GWAS provided insights into genetic mechanisms underpinning AGEP4, further work is required to test genomic predictions of fertility that use this information.


Assuntos
Fertilidade , Estudo de Associação Genômica Ampla , Lactação , Animais , Bovinos/genética , Fertilidade/genética , Feminino , Lactação/genética , Fenótipo , Maturidade Sexual/genética , Gravidez , Genótipo
2.
J Dairy Sci ; 106(11): 7846-7860, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37641287

RESUMO

Anogenital distance (AGD) is a moderately heritable trait that can be measured at a young age that may provide an opportunity to indirectly select for improved fertility in dairy cattle. In this study, we characterized AGD and its genetic and phenotypic relationships with a range of body stature and fertility traits. We measured AGD, shoulder height, body length, and body weight in a population of 5,010 Holstein-Friesian and Holstein-Friesian × Jersey crossbred heifers at approximately 11 mo of age (AGD1). These animals were born in 2018 across 54 seasonal calving, pasture-based dairy herds. A second measure of AGD was collected in a subset of herds (n = 17; 1,956 animals) when the animals averaged 29 mo of age (AGD2). Fertility measures included age at puberty (AGEP), then time of calving, breeding, and pregnancy during the first and second lactations. We constructed binary traits reflecting the animal's ability to calve during the first 42 d of their herd's seasonal calving period (CR42), be presented for breeding during the first 21 d of the seasonal breeding period (PB21) and become pregnant during the first 42 d of the seasonal breeding period (PR42). The posterior mean of sampled heritabilities for AGD1 was 0.23, with 90% of samples falling within a credibility interval (90% CRI) of 0.20 to 0.26, whereas the heritability of AGD2 was 0.29 (90% CRI 0.24 to 0.34). The relationship between AGD1 and AGD2 was highly positive, with a genetic correlation of 0.89 (90% CRI 0.82 to 0.94). Using a GWAS analysis of 2,460 genomic windows based on 50k genotype data, we detected a region on chromosome 20 that was highly associated with variation in AGD1, and a second region on chromosome 13 that was moderately associated with variation in AGD1. We did not detect any genomic regions associated with AGD2 which was measured in fewer animals. The genetic correlation between AGD1 and AGEP was 0.10 (90% CRI 0.00 to 0.19), whereas the genetic correlation between AGD2 and AGEP was 0.30 (90% CRI 0.15 to 0.44). The timing of calving, breeding, and pregnancy (CR42, PB21, and PR42) during first or second lactations exhibited moderate genetic relationships with AGD1 (0.19 to 0.52) and AGD2 (0.46 to 0.63). Genetic correlations between AGD and body stature traits were weak (≤0.16). We conclude that AGD is a moderately heritable trait, which may have value as an early-in-life genetic predictor for reproductive success during lactation.

3.
N Z Vet J ; 71(5): 213-225, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37431287

RESUMO

AIMS: To explore animal- and herd-level risk factors influencing age at puberty in predominantly Holstein-Friesian dairy heifers managed in seasonal, pasture-based systems. METHODS: Heifers born in spring 2018 (n = 5,010) from 54 commercial dairy herds in New Zealand were visited on three occasions when the mean heifer age, within herd, was 10 (visit 1; V1), 11 (V2) and 12 (V3) months old. Blood samples were collected on each visit and liveweight, stature and anogenital distance (AGD) were measured at V2. Heifers were defined as having reached puberty at the first visit where blood progesterone was elevated (≥ 1 ng/mL). Animal-level response variables included pubertal status by V1, V2 and V3, and age at puberty (or age at V3 plus 31 days for those that had not attained puberty by V3). To explore herd-level management factors, farmers answered a questionnaire relating to animal location, land type, health, feeding, and management between weaning and mating. A partial least squares regression was undertaken to identify herd-level factors associated with the greatest influence on puberty rate within herd. RESULTS: The mean age at puberty was 352 (SD 34.9) days. Heavier animals at a greater proportion of expected mature liveweight based on their breeding value for liveweight, or animals with a higher breed proportion of Jersey and lower breed proportion of Holstein, were associated with earlier puberty. Herd puberty rates varied widely among enrolled herds, and averaged 20%, 39% and 56% by V1, V2 and V3, respectively. Liveweight, followed by breed and land type, had the greatest influence on the herd puberty rate. Heifer herds with a greater mean liveweight (absolute and proportion of expected mature weight) or greater Jersey proportion had more animals that reached puberty at any visit, whereas herds located on steep land or with greater Holstein breed proportions had lower puberty rates. Management-related factors such as vaccinations, provision of feed supplements, and weighing frequency were also herd-level risk factors of puberty but had less influence. CONCLUSIONS AND CLINICAL RELEVANCE: This study highlights the importance of having well-grown heifers for increasing the chances of earlier puberty onset and the effect of breed and youngstock management to achieve growth targets. These outcomes have important implications for the optimal management of heifers to achieve puberty before their maiden breeding and for the timing of measurements to potentially incorporate a puberty trait in genetic evaluations.


Assuntos
Reprodução , Maturidade Sexual , Gravidez , Bovinos , Animais , Feminino , Maturidade Sexual/fisiologia , Fatores de Risco , Parto , Suplementos Nutricionais
4.
J Dairy Sci ; 105(3): 2369-2379, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35086707

RESUMO

Clinical mastitis (CM) incidence is considerable in terms of cows affected per year, but cases are much less common in terms of detections per cow per milking. From a modeling perspective, where predictions are made every time any cow is milked, low CM incidence per cow day makes training, evaluating, and applying CM prediction models a challenge. The objective of this study was to build models for predicting CM incidence using time-series sensor data and choose models that maximize net return based on a cost matrix. Data collected from 2 university dairy farms, the University of Florida and Virginia Polytechnic Institute and State University, were used to gather representative data, including 110,156 milkings and 333 CM cases. Variables used in the models were milk yield, protein, lactose, fat, electrical conductivity, days in milk, lactation number, and activity as the number of steps, lying time, lying bouts, and lying bout duration. Models that predicted either likelihood of CM caused by gram-negative (GN) or gram-positive (GP) bacteria on each day were derived using extreme gradient boosting with weighting favoring true-positive cases, logistic responses, and log-loss errors. Model accuracies were determined using data randomly held out from the training set on each run. All variables considered were in terms of change (slope) over previous days, including the day CM was visually detected. The GN models had a median sensitivity (Se) of 52.6% and specificity (Sp) of 99.8%, whereas the GP models had a median Se of 37.5% and Sp of 99.9% when tested on the held-out data. In our models optimized to reduce cost from predictions, the Se was much less than Sp, suggesting that CM models might benefit from greater model weighting placed on Sp. Results also highlight the importance of positive predictive value (true positive cases per predicted positive case) along with Sp and Se, as models built on sparse data tend to predict too many false-positive cases. The calculated partial net return of our GN and GP models were -$0.15 and -$0.10 per cow per lactation, respectively, whereas International Organization for Standardization (ISO) standard models with Se of 80% and Sp of 99% would return -$1.32 per cow per lactation. Models chosen that minimized the cost to the farmer differed markedly from models that met ISO guidelines, showing asymmetry in targets between Sp and Se when the disease incidence rate is low. Because of the unique challenges that low-incidence diseases like CM present, we recommend that future CM predictive models consider the economic and practical implications in addition to the traditional model evaluation metrics.


Assuntos
Indústria de Laticínios , Mastite Bovina , Animais , Bovinos , Indústria de Laticínios/métodos , Fazendas , Feminino , Incidência , Lactação , Mastite Bovina/microbiologia , Leite/metabolismo
5.
Osteoporos Int ; 32(4): 645-651, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33151378

RESUMO

The Forteo Patient Registry estimated the incidence of osteosarcoma in US patients treated with teriparatide and enrolled in the study between 2009 and 2019. No incident cases of osteosarcoma were identified among patients registered, and the crude incidence rate was 0 (95% confidence interval [CI], 0-10.2) cases per million person-years. PURPOSE: The prospective, voluntary Forteo Patient Registry was established to estimate the incidence of osteosarcoma in patients who have received treatment with teriparatide (Forteo). METHODS: Information on US adults prescribed teriparatide and enrolled in the Forteo Patient Registry 2009-2019 was linked with data from participating state cancer registries annually (2010-2019) to identify incident osteosarcoma cases using a standardized linkage algorithm. Teriparatide exposure was ascertained from self-reported data that included teriparatide initiation and demographics necessary to complete linkage. Osteosarcoma cases diagnosed on or after January 1, 2009, were identified by participating state cancer registries. The crude incidence rate (IR) and standardized incidence ratio (SIR) of observed cases to the expected number of cases adjusted to the background rate (3 per million person-years) and corresponding 95% CIs for the occurrence of osteosarcoma were calculated whereby the cumulative amount of person-time observed was adjusted for mortality. RESULTS: Data for 75,247 enrolled patients (representing 361,763 cumulative person-years) were linked to each of 42 participating state cancer registries (covering 93% of the US population), which included information on 6180 cases of osteosarcoma. No matches with incident cases of osteosarcoma following registry enrollment were found. The crude IR was 0 (95% CI, 0-10.2) cases per million person-years and the SIR was 0 (95% CI, 0-3.0). CONCLUSIONS: The ability to draw conclusions about the incidence of osteosarcoma among patients participating in the registry was limited due to the smaller than expected amount of patient follow-up time and the fact that no cases were identified.


Assuntos
Neoplasias Ósseas , Neoplasias , Osteossarcoma , Adulto , Neoplasias Ósseas/epidemiologia , Humanos , Incidência , Osteossarcoma/epidemiologia , Estudos Prospectivos , Sistema de Registros , Teriparatida/uso terapêutico
6.
J Dairy Sci ; 103(3): 2602-2614, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31882223

RESUMO

Opportunities exist for automated animal health monitoring and early detection of diseases such as mastitis with greater on-farm adoption of precision technologies. Our objective was to evaluate time series changes in individual milk component or behavioral variables for all clinical mastitis (CM) cases (ACM), for CM caused by gram-negative (GN) or gram-positive (GP) pathogens, or CM cases in which no pathogen was isolated (NPI). We developed algorithms using a combination of milk and activity parameters for predicting each of these infection types. Milk and activity data were collated for the 14 d preceding a CM event (n = 170) and for controls (n = 166) matched for breed, parity, and days in milk. Explanatory variables in the univariate and multiple regression models were the slope change in milk (milk yield, conductivity, somatic cell count, lactose percentage, protein percentage, and fat percentage) and activity parameters (steps, lying time, lying bout duration, and number of lying bouts) over 7 d. Slopes were estimated using linear regression between d -7 and -5, d -7 and -4, d -7 and -3, d -7 and -2, and d -7 and -1 relative to CM detection for all parameters. Univariate analyses determined significant slope ranges for explanatory variables against the 4 responses: ACM, GN, GP, and NPI. Next, all slope ranges were offered into the multivariate models for the same 4 responses using 3 baselines: d -10, -7, and -3 relative to CM detection. In the univariate analysis, no explanatory variables were significant indicators of ACM, whereas at least 1 parameter was significant for each of GN, GP, and NPI models. Superior sensitivity (Se) and specificity (Sp) estimates were observed for the best GP (Se = 82%, Sp = 87%) and NPI (Se = 80%, Sp = 94%) multiple regression models compared with the best ACM (Se = 73%, Sp = 75%) and GN (Se = 71%, Sp = 74%) models. Sensitivity for the GN model was greater at the baseline closest to the day of CM detection (d -3), whereas the opposite was observed for the GP and NPI model as Se was maximized at the d -10 baseline. Based on this screening of relationships, milk and activity sensor data could be used in CM detection systems.


Assuntos
Algoritmos , Comportamento Animal , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/isolamento & purificação , Mastite Bovina/diagnóstico , Leite/química , Animais , Bovinos , Contagem de Células/veterinária , Indústria de Laticínios , Condutividade Elétrica , Fazendas , Feminino , Lactação , Lactose/análise , Modelos Lineares , Mastite Bovina/microbiologia , Leite/metabolismo , Leite/normas , Paridade , Gravidez , Sensibilidade e Especificidade
7.
Anaesthesia ; 74(3): 292-299, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30623418

RESUMO

The primary objective of this quality improvement project was to measure and reduce the number of oxycodone immediate-release tablets dispensed to overnight stay surgical patients at discharge. The secondary objective was to reduce the proportion of inappropriate oxycodone immediate-release prescriptions at discharge. Interrupted time series analysis was performed in four surgical wards of St Vincent's Public Hospital, Sydney. The baseline period was from January 2005 to August 2013. Interventions and follow-up occurred until July 2017. Baseline audit of oxycodone immediate-release tablet numbers showed prescribing increased significantly with a monthly linear trend of 1.8 (95%CI = 1.4-2.3; p = 0.001) tablets/100 surgical admissions from January 2005 to August 2013. Four sequential interventions produced no significant change in the primary objective. At the end of the first month of a fifth intervention, comprising audit-feedback plus individual academic detailing, the average number of oxycodone tablets decreased by 77 (95%CI 39-115) tablets/100 surgical cases, and the postintervention linear trend was a monthly reduction of 3.2 (coefficient -3.2 (95%CI -4.5 to -1.8); p = 0.001) tablets/100 surgical admissions. Baseline audit showed 27% of oxycodone prescriptions to be inappropriate. Following our intervention, this dropped to 17% (p = 0.048), and then to 10% (p = 0.002) after 3 years.


Assuntos
Analgésicos Opioides/uso terapêutico , Oxicodona/uso terapêutico , Humanos , Alta do Paciente , Melhoria de Qualidade , Encaminhamento e Consulta , Centros de Atenção Terciária
8.
J Dairy Sci ; 102(12): 11233-11249, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31606213

RESUMO

Vaccination against coliform mastitis has become part of mastitis control programs in the past 3 decades, as a means of reducing the severity of clinical mastitis. Our study objective was to evaluate the effect of 2 commercially available vaccines on clinical, behavioral, and antibody response following Escherichia coli intramammary challenge in cows near peak lactation. Cows (n = 12 per group) were vaccinated with vaccine 1 (V1) or vaccine 2 (V2) at dry-off, 21 d pre-calving, and 14 d post-calving. Twelve cows served as unvaccinated controls (CTL). Cows were challenged with E. coli in a rear quarter at approximately 100 d in milk. Milk samples were collected pre- and post-challenge to enumerate E. coli and determine somatic cell count. Serum was collected before each vaccination and at d 0, 1, 2, 3, 6, 30, and 60 relative to challenge, to study antibody response. Milk IgA and tumor necrosis factor-α concentrations were determined in whey. Vaginal temperature, cow activity, and milk yield and components were monitored post-challenge. Bacterial count, somatic cell score, milk yield and component decline, vaginal temperature, activity measures, and antibody and cytokine response were analyzed for treatment differences. The effects of parity, breed, and a repeated measure of time were also tested. Seven cows had to be removed from the study post-challenge for antibiotic treatment (CTL and V1, n = 3 each; V2, n = 1), 2 of which were euthanized (both CTL). Vaccinated cows exhibited fever (vaginal temperature ≥39.4°C) 3 h earlier than CTL cows, but we found no differences between treatments for bacterial count, somatic cell score, or milk yield reduction. Vaccinated cows spent more time lying per rest bout 2 d post-challenge, but total daily lying time was not different from CTL cows during the 7 d post-challenge. The vaccines differed in antibody response: V1 cows had greater serum IgG1 and IgG2 post-challenge. A parity effect was also evident: primiparous cows had lower bacterial counts, somatic cell score and a smaller milk yield decline than multiparous cows, but also had lower antibody production. Immunization with either J5 bacterin did not reduce clinical signs of mastitis in cows challenged at 100 d in milk, demonstrating that the effects of J5 vaccination had diminished at peak lactation.


Assuntos
Infecções por Escherichia coli/veterinária , Vacinas contra Escherichia coli/imunologia , Imunogenicidade da Vacina , Mastite Bovina/prevenção & controle , Animais , Anticorpos Antibacterianos/sangue , Bovinos , Contagem de Células/veterinária , Escherichia coli/imunologia , Vacinas contra Escherichia coli/administração & dosagem , Feminino , Humanos , Imunoglobulina G/sangue , Lactação , Mastite Bovina/imunologia , Mastite Bovina/microbiologia , Leite/citologia , Leite/microbiologia , Paridade , Gravidez , Vacinação/veterinária
9.
Ann Oncol ; 29(9): 1918-1925, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30016392

RESUMO

Background: We have previously shown that raised p-S6K levels correlate with resistance to chemotherapy in ovarian cancer. We hypothesised that inhibiting p-S6K signalling with the dual m-TORC1/2 inhibitor in patients receiving weekly paclitaxel could improve outcomes in such patients. Patients and methods: In dose escalation, weekly paclitaxel (80 mg/m2) was given 6/7 weeks in combination with two intermittent schedules of vistusertib (dosing starting on the day of paclitaxel): schedule A, vistusertib dosed bd for 3 consecutive days per week (3/7 days) and schedule B, vistusertib dosed bd for 2 consecutive days per week (2/7 days). After establishing a recommended phase II dose (RP2D), expansion cohorts in high-grade serous ovarian cancer (HGSOC) and squamous non-small-cell lung cancer (sqNSCLC) were explored in 25 and 40 patients, respectively. Results: The dose-escalation arms comprised 22 patients with advanced solid tumours. The dose-limiting toxicities were fatigue and mucositis in schedule A and rash in schedule B. On the basis of toxicity and pharmacokinetic (PK) and pharmacodynamic (PD) evaluations, the RP2D was established as 80 mg/m2 paclitaxel with 50 mg vistusertib bd 3/7 days for 6/7 weeks. In the HGSOC expansion, RECIST and GCIG CA125 response rates were 13/25 (52%) and 16/25 (64%), respectively, with median progression-free survival (mPFS) of 5.8 months (95% CI: 3.28-18.54). The RP2D was not well tolerated in the SqNSCLC expansion, but toxicities were manageable after the daily vistusertib dose was reduced to 25 mg bd for the following 23 patients. The RECIST response rate in this group was 8/23 (35%), and the mPFS was 5.8 months (95% CI: 2.76-21.25). Discussion: In this phase I trial, we report a highly active and well-tolerated combination of vistusertib, administered as an intermittent schedule with weekly paclitaxel, in patients with HGSOC and SqNSCLC. Clinical trial registration: ClinicialTrials.gov identifier: CNCT02193633.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Benzamidas/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/patologia , Morfolinas/administração & dosagem , Neoplasias Ovarianas/tratamento farmacológico , Inibidores de Proteínas Quinases/administração & dosagem , Pirimidinas/administração & dosagem , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Benzamidas/efeitos adversos , Benzamidas/farmacocinética , Carcinoma Pulmonar de Células não Pequenas/patologia , Esquema de Medicação , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Dose Máxima Tolerável , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Alvo Mecanístico do Complexo 2 de Rapamicina/antagonistas & inibidores , Pessoa de Meia-Idade , Morfolinas/efeitos adversos , Morfolinas/farmacocinética , Neoplasias Ovarianas/patologia , Paclitaxel/administração & dosagem , Paclitaxel/efeitos adversos , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/efeitos adversos , Inibidores de Proteínas Quinases/farmacocinética , Pirimidinas/efeitos adversos , Pirimidinas/farmacocinética , Critérios de Avaliação de Resposta em Tumores Sólidos , Proteínas Quinases S6 Ribossômicas/metabolismo
10.
Osteoporos Int ; 29(10): 2335-2343, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29978254

RESUMO

The Forteo Patient Registry (FPR) aims to estimate the incidence of osteosarcoma in US patients treated with teriparatide. Enrollment began in 2009 and will continue through 2019, with linkage planned through 2024. To date, no incident cases of osteosarcoma have been identified among patients registered in the FPR. INTRODUCTION: The Forteo Patient Registry (FPR) was established in 2009 to estimate the incidence of osteosarcoma in US patients treated with teriparatide. The objective of this paper is to describe study methods, challenges encountered, and progress to date. METHODS: The FPR is a prospective US registry designed to link data from participants annually with state cancer registries. Patient enrollment is planned for 10 years (2009-2019) and annual linkage with US state cancer registries for 15 years (2010-2024). All US state cancer registries and DC were invited to participate. Patients are recruited using pre-enrollment materials included in teriparatide device packaging, kits, and brochures distributed by health-care providers; a toll-free number; and a study website. A linkage algorithm is used to match data from enrolled participants with cancer registry data. RESULTS: For the eighth annual linkage in 2017, information necessary for linkage with 63,270 patients in the FPR was submitted to each of the 42 participating registries. These patients contributed approximately 242,782 person-years of follow-up. A total of 5268 adult osteosarcoma cases diagnosed since January 1, 2009, were available for linkage from participating state cancer registries. To date, no incident cases of osteosarcoma have been identified among patients registered in the FPR. CONCLUSIONS: Based on the estimated 242,782 person-years of observation as of the eighth annual linkage and projecting current enrollment rate to study end in 2024, it is anticipated that the completed study will be able to detect a fourfold increase in the risk of osteosarcoma if one exists.


Assuntos
Neoplasias Ósseas/epidemiologia , Registro Médico Coordenado/métodos , Osteossarcoma/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Conservadores da Densidade Óssea/efeitos adversos , Neoplasias Ósseas/induzido quimicamente , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteossarcoma/induzido quimicamente , Seleção de Pacientes , Vigilância de Produtos Comercializados/métodos , Sistema de Registros , Projetos de Pesquisa , Teriparatida/efeitos adversos , Estados Unidos/epidemiologia , Adulto Jovem
11.
J Dairy Sci ; 100(5): 3816-3824, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28237588

RESUMO

The performance of a commercial, real-time PCR assay was compared with traditional bacterial culture for the identification of Streptococcus uberis and Staphylococcus aureus in bovine milk collected at different stages of lactation. Initial validation tests using fresh and frozen quarter milk samples identified factors that affected the success of the PCR. Therefore, the standard protocol was adjusted for samples collected at the first milking postpartum (colostrum) and from clinical mastitis cases. The adjustment involved PCR testing both undiluted and diluted (1 in 10 with sterile water) DNA extracts. The performance comparison between culture and the PCR assay used milk samples collected aseptically from individual quarters of mixed-age spring-calving dairy cows, during early, mid, and late lactation. Bacterial culture results were used to select a subset of samples for PCR testing (n = 315) that represented quarters with a current or prior Strep. uberis or Staph. aureus infection. Compared with culture, PCR had a sensitivity of 86.8% and specificity of 87.7% for detecting Strep. uberis (kappa = 0.74) and 96.4% and 99.7%, respectively, for detecting Staph. aureus (kappa = 0.96). The dilution of DNA extracts for colostrum and clinical samples increased the relative sensitivity from 79.2% to 86.8% for Strep. uberis detection and from 92.9% to 96.4% for Staph. aureus, presumably through diluting unidentified PCR inhibitors. The sensitivity for detecting Strep. uberis using PCR, relative to culture, was similar throughout lactation (85-89%), whereas relative specificity was lowest immediately postcalving (64%) but improved in mid and late lactation (98%). Specificity estimates for samples collected in early lactation can be optimized by reducing the cutoff cycle threshold (Ct) value from the recommended value of 37 to 34. Although using this value improved specificity (77%), it reduced test sensitivity (77%). The PCR assay lacked agreement with culture in early lactation, specifically for diagnosing Strep. uberis. Thus, PCR should not be used as the only tool for diagnosing mastitis in early lactation.


Assuntos
Mastite Bovina/microbiologia , Staphylococcus aureus/genética , Animais , Bovinos , Feminino , Lactação , Leite/microbiologia , Infecções Estafilocócicas/veterinária , Infecções Estreptocócicas/veterinária , Streptococcus
12.
Br J Cancer ; 106(5): 793-8, 2012 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-22315057

RESUMO

BACKGROUND: Pre-clinical data indicate enhanced anti-tumour activity when combining recombinant human interleukin-21 (rIL-21), a class 1 cytokine, with cetuximab, a monoclonal antibody, targeting the epidermal growth factor receptor. This phase 1 trial assessed the safety and tolerability of escalating doses of rIL-21 in combination with cetuximab in chemo-naïve patients with stage IV colorectal cancer. PATIENTS AND METHODS: Sequential cohorts of PS 0-1, asymptomatic patients, were treated weekly with cetuximab 250 mg m(-2) intravenously (i.v.) plus escalating i.v. doses of rIL-21 following an initial loading dose of cetuximab 400 mg m(-2). Initial treatment period was 8 weeks, with extension permitted in patients without disease progression. RESULTS: In all, 15 patients were included in this study. Adverse events related to rIL-21 or rIL-21 plus cetuximab included lethargy, nausea/vomiting, stomatitis, lymphopenia and pyrexia and were mainly ≤ grade 2. One dose limiting toxicity occurred (grade 3 diarrhoea). Maximum tolerated dose was not determined because of the premature study closure. Maximum administered dose was 100 µg kg(-1) rIL-21 weekly. In all, 60% of the patients had stable disease. Immune activation was confirmed by various T- and NK-cell activation biomarkers, including dose-dependent increases in serum sCD25. CONCLUSION: rIL-21 weekly combined with cetuximab is well tolerated at doses up to 100 µg kg(-1) and results in activation of immune response biomarkers.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Interleucinas/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Cetuximab , Neoplasias Colorretais/patologia , Receptores ErbB/imunologia , Feminino , Humanos , Interleucinas/efeitos adversos , Interleucinas/uso terapêutico , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Metástase Neoplásica , Resultado do Tratamento
13.
Br J Cancer ; 100(5): 758-63, 2009 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-19259094

RESUMO

Histone deacetylation and DNA methylation have a central role in the control of gene expression in tumours, including transcriptional repression of tumour suppressor genes and genes involved in sensitivity to chemotherapy. Treatment of cisplatin-resistant cell lines with an inhibitor of DNA methyltransferases, 2-deoxy-5'azacytidine (decitabine), results in partial reversal of DNA methylation, re-expression of epigenetically silenced genes including hMLH1 and sensitisation to cisplatin both in vitro and in vivo. We have investigated whether the combination of decitabine and a clinically relevant inhibitor of histone deacetylase activity (belinostat, PXD101) can further increase the re-expression of genes epigenetically silenced by DNA methylation and enhance chemo-sensitisation in vivo at well-tolerated doses. The cisplatin-resistant human ovarian cell line A2780/cp70 has the hMLH1 gene methylated and is resistant to cisplatin both in vitro and when grown as a xenograft in mice. Treatment of A2780/cp70 with decitabine and belinostat results in a marked increase in expression of epigenetically silenced MLH1 and MAGE-A1 both in vitro and in vivo when compared with decitabine alone. The combination greatly enhanced the effects of decitabine alone on the cisplatin sensitivity of xenografts. As the dose of decitabine that can be given to patients and hence the maximum pharmacodynamic effect as a demethylating agent is limited by toxicity and eventual re-methylation of genes, we suggest that the combination of decitabine and belinostat could have a role in the efficacy of chemotherapy in tumours that have acquired drug resistance due to DNA methylation and gene silencing.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , DNA (Citosina-5-)-Metiltransferases/antagonistas & inibidores , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Inibidores Enzimáticos/administração & dosagem , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Histona Acetiltransferases/antagonistas & inibidores , Neoplasias Ovarianas/tratamento farmacológico , Acetilação/efeitos dos fármacos , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Azacitidina/administração & dosagem , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Metilação de DNA/efeitos dos fármacos , Decitabina , Resistencia a Medicamentos Antineoplásicos/genética , Inibidores Enzimáticos/farmacologia , Feminino , Humanos , Ácidos Hidroxâmicos/administração & dosagem , Antígenos Específicos de Melanoma , Camundongos , Camundongos Nus , Proteína 1 Homóloga a MutL , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares/genética , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Sulfonamidas , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Breast ; 15(3): 430-6, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16236514

RESUMO

Exemestane is a potent steroidal aromatase inhibitor (AI) with activity in post-menopausal women with metastatic breast cancer, with a reported clinical benefit (CB) rate of 24.3% after prior AI therapy. Data on 114 patients (112 female, 2 male) were obtained retrospectively at two cancer centres. Sixty-five percent of patients were confirmed as oestrogen receptor (ER) positive. All patients had received prior third-generation AI therapy. Responses were seen in 5% and the overall CB rate (CR+PR+SD24 weeks) was 46%. Median PFS and OS were 18 and 61 weeks, respectively. In patients with visceral disease, the CBR was 33%. Patients with known ER-positive disease had a CBR of 47%, and a median TTP of 19 weeks. No benefit was seen in patients with known ER-negative disease. Survival was better in those with CB (median survival not reached in those with CB, 28 weeks in those without CB P<0.0001). Efficacy persisted in those patients who had received 3 prior lines of hormonal therapy, including adjuvant treatment. These data confirm exemestane to be an effective therapy after third-generation non-steroidal AI in post-menopausal ER-positive metastatic breast cancer, including visceral disease.


Assuntos
Androstadienos/uso terapêutico , Inibidores da Aromatase/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/mortalidade , Neoplasias da Mama/secundário , Progressão da Doença , Feminino , Humanos , Masculino , Receptores de Estrogênio , Estudos Retrospectivos , Falha de Tratamento
16.
Biochim Biophys Acta ; 941(1): 71-5, 1988 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-3370213

RESUMO

A number of biliary secretory processes are inhibited by administration of ampicillin to isolated perfused rat livers. Reduction in output was observed for phospholipid, cholesterol, the endogenous protein rat serum albumin and the exogenous protein bovine serum albumin, whilst secretin of bile salts was virtually unaffected. All of the affected materials are secreted by processes involving vesicles which are brought to the appropriate pole of the hepatocyte, and the observed inhibitory effects of ampicillin may, therefore, possibly be due to a blockage in the transport of these substances. The effects of ampicillin were much less marked on materials secreted at the sinusoidal pole of the cell.


Assuntos
Ampicilina/farmacologia , Bile/metabolismo , Fígado/efeitos dos fármacos , Animais , Ácidos e Sais Biliares/metabolismo , Colesterol/metabolismo , Grânulos Citoplasmáticos/efeitos dos fármacos , Fígado/metabolismo , Fosfolipídeos/metabolismo , Ratos , Albumina Sérica/metabolismo , Triglicerídeos/metabolismo
17.
Plant Physiol ; 114(1): 373-381, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-12223710

RESUMO

The class of cell wall polysaccharides that undergoes the most extensive modification during tomato (Lycopersicon esculentum) fruit ripening is pectin. De-esterification of the polygalacturonic acid backbone by pectin methylesterase facilitates the depolymerization of pectins by polygalacturonase II (PGII). To investigate the spatial aspects of the de-esterification of cell wall pectins and the subsequent deposition of PGII, we have used antibodies to relatively methylesterified and nonesterified pectic epitopes and to the PGII protein on thin sections of pericarp tissue at different developmental stages. De-esterification of pectins and deposition of PGII protein occur in block-like domains within the cell wall. The boundaries of these domains are distinct and persistent, implying strict, spatial regulation of enzymic activities. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of proteins strongly associated with cell walls of pericarp tissue at each stage of fruit development show ripening-related changes in this protein population. Western blots of these gels with anti-PGII antiserum demonstrate that PGII expression is ripening-related. The PGII co-extracts with specific pectic fractions extracted with imidazole or with Na2CO3 at 0[deg]C from the walls of red-ripe pericarp tissue, indicating that the strong association between PGII and the cell wall involves binding to particular pectic polysaccharides.

18.
J Bone Joint Surg Br ; 87(2): 209-12, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15736745

RESUMO

We prospectively studied the outcome of a protocol of prophylaxis for deep vein thrombosis (DVT) in 103 consecutive patients undergoing surgical stabilisation of pelvic and acetabular fractures. Low-molecular-weight heparin (LMWH) was administered within 24 hours of injury or on achieving haemodynamic stability. Patients were screened for proximal DVT by duplex ultrasonography performed ten to 14 days after surgery. The incidence of proximal DVT was 10% and of pulmonary embolus 5%. Proximal DVT developed in two of 64 patients (3%) who had received LMWH within 24 hours of injury, but in eight of 36 patients (22%) who received LMWH more than 24 hours after the injury (p < 0.01). We conclude that LMWH, when begun without delay, is a safe and effective method of thromboprophylaxis in high-risk patients with major pelvic or acetabular fractures.


Assuntos
Acetábulo/lesões , Anticoagulantes/uso terapêutico , Heparina de Baixo Peso Molecular/uso terapêutico , Ossos Pélvicos/lesões , Terapia Trombolítica/métodos , Trombose Venosa/prevenção & controle , Acetábulo/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/efeitos adversos , Criança , Feminino , Fraturas Ósseas/complicações , Fraturas Ósseas/cirurgia , Heparina de Baixo Peso Molecular/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Ossos Pélvicos/cirurgia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Estudos Prospectivos , Embolia Pulmonar/etiologia , Embolia Pulmonar/prevenção & controle , Trombose Venosa/etiologia
19.
Am J Clin Nutr ; 52(1): 147-54, 1990 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2360543

RESUMO

The ability of carbohydrates (CHO), such as fructose and sucrose, to aggravate copper deficiency in rats and the recent dietary trends of Western human populations led to the suggestion that the Cu X CHO interaction may be pertinent to public health. This hypothesis was tested with pigs because their cardiovascular and gastrointestinal systems closely resemble those of humans. Weanling pigs were fed a diet containing either 59% sucrose or cornstarch with either deficient (0.8 mg/kg diet) or adequate (6.4 mg/kg) copper for 10 wk. Plasma and tissue copper, the activities of plasma ceruloplasmin ferroxidase and erythrocyte Cu,Zn-superoxide dismutase, hematocrits, and serum cholesterol and triglyceride were all decreased (p less than 0.05) and relative cardiac mass was increased (p less than 0.05) by severe dietary copper deficiency. The type of dietary CHO did not differentially influence the values of these variables. Thus, these data fail to support the hypothesis that the Cu X CHO interaction observed in rats represents a health risk for humans.


Assuntos
Cobre/deficiência , Carboidratos da Dieta/metabolismo , Animais , Peso Corporal/efeitos dos fármacos , Cobre/administração & dosagem , Cobre/farmacocinética , Carboidratos da Dieta/administração & dosagem , Feminino , Coração/efeitos dos fármacos , Hematócrito , Masculino , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Endogâmicos , Amido/administração & dosagem , Sacarose/administração & dosagem , Suínos , Distribuição Tecidual
20.
Pediatrics ; 77(3): 289-95, 1986 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3485275

RESUMO

In 1982, an outbreak of Haemophilus influenzae type b disease occurred in a 379-member Amish community. In an attempt to control the outbreak after the occurrence of the second case of disease, we investigated the combination of (1) rifampin chemoprophylaxis of all carriers of H influenzae type b and their household contacts from 1 month to 5 years of age and (2) H influenzae type b polysaccharide vaccine immunoprophylaxis of all community members 12 months of age and older. Despite our intervention, two additional cases of bacteremic H influenzae type b disease occurred in the ensuing 5 months, one in a 22-month-old infant who had been immunized at 19 months of age and the other in a child who had not been immunized because she was younger than 12 months of age. The outbreak ended following rifampin prophylaxis of all community members younger than 15 years of age. All of the children with disease were genetically related to one another, and three of the four were inbred. However, analysis of their coancestry revealed that neither the average level of kinship nor the average inbreeding level of the affected children differed significantly from those of the other children in the community. Furthermore, none of the four children with disease shared a human leukocyte antigen haplotype. Our observations suggest that inbreeding was not a risk factor in this community.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Surtos de Doenças/epidemiologia , Suscetibilidade a Doenças , Etnicidade , Infecções por Haemophilus/epidemiologia , Imunização , Rifampina/uso terapêutico , Adulto , Vacinas Bacterianas , Portador Sadio/microbiologia , Celulite (Flegmão)/epidemiologia , Criança , Pré-Escolar , Surtos de Doenças/prevenção & controle , Seguimentos , Infecções por Haemophilus/genética , Infecções por Haemophilus/prevenção & controle , Haemophilus influenzae/imunologia , Humanos , Imunização Secundária , Lactente , Recém-Nascido , Meningite por Haemophilus/epidemiologia , Missouri , Linhagem , Polissacarídeos Bacterianos/imunologia , População Rural
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