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1.
J Dairy Sci ; 102(12): 11504-11522, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31587901

RESUMO

Water is essential in livestock production systems. In typical dairy production systems, 90% of the total water used by a dairy farm is attributed to feed production. Theoretically, ration manipulation is a method to potentially reduce the irrigation water needed for feed crops without dramatically increasing diet costs. However, published quantitative studies on the relationship between feed production and water use that are integrated with linear programming models are scarce. The overall objective of this study was to develop an optimization framework that could achieve a balance between minimization of dietary costs and dietary irrigation water usage, and that could be used as a framework for future research and models for various livestock production systems. Weighted goal programming models were developed to minimize the dietary costs and irrigation water usage for a hypothetical cow under 8 different environmental scenarios. The environmental conditions used a 2 × 2 × 2 factorial design, including 2 atmospheric CO2 concentrations (400 and 550 ppm), 2 water years (dry and wet), and 2 irrigation methods (furrow and drip). A systematic weighting scheme was used to model the trade-off between minimizing diet cost and minimizing irrigation water use for feedstuffs. Each environmental condition generated a set of distinct diets, which each met the same nutrient requirements of the hypothetical cow but had a different water usage when the weighting scheme was changed from weighting minimum diet costs to minimum irrigation water usage. For water resource planning in areas of dairy production, this set of unique solutions provides the decision maker with different feeding options according to diet cost, water usage, and available feeds. As water was more constrained, dietary dry matter intake increased, concentrations of neutral detergent fiber, ether extract, and energy decreased, and the concentration of lignin increased because less nutritive but more water-saving feedstuffs were included in the diet. Mitigation costs of water usage were calculated from goal programming results and indicated that the potential value of water under water-limited conditions (e.g., in a drought region) was higher than that under water-sufficient conditions. However, a smaller increase in feed costs can initially significantly reduce water usage compared with that of a least-cost diet, which implies that the reduction of water usage through ration manipulation might be possible. This model serves as a framework for the study of irrigation water usage in dairy production and other livestock production systems and for decision-making processes involved in water resources planning in the broader area of animal production.


Assuntos
Ração Animal/economia , Bovinos , Dieta/veterinária , Água Potável , Animais , Custos e Análise de Custo , Indústria de Laticínios/economia , Dieta/economia , Meio Ambiente , Feminino , Lactação , Necessidades Nutricionais , Programação Linear
2.
Phys Rev Lett ; 121(9): 097701, 2018 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-30230891

RESUMO

We report on the fabrication of Josephson junctions using the topological crystalline insulator Pb_{0.5}Sn_{0.5}Te as the weak link. The properties of these junctions are characterized and compared to those fabricated with weak links of PbTe, a similar material yet topologically trivial. Most striking is the difference in the ac Josephson effect: junctions made with Pb_{0.5}Sn_{0.5}Te exhibit a rich subharmonic structure consistent with a skewed current-phase relation. This structure is absent in junctions fabricated from PbTe. A discussion is given on the origin of this effect as an indication of novel behavior arising from the topologically nontrivial surface state.

3.
J Oncol Pharm Pract ; 24(4): 264-271, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29284360

RESUMO

Background Anthracycline-based chemotherapy is used in many malignancies. Current recommendations by several groups suggest cardiac monitoring prior to and during anthracycline therapy. We aim to review the usefulness of baseline cardiac screening for left ventricular ejection fraction to assess if it had any impact on chemotherapy decisions in patients to be treated with anthracycline-based regimens or any beneficial effect upon outcomes. Methods We conducted a retrospective three-year audit of cancer patients who underwent GBPS prior to anthracycline (doxorubicin) chemotherapy. Subjects were identified via records from the Department of Nuclear Medicine. Pharmacy dispensing records identified those who received doxorubicin. Patient demographics, cancer type, cardiac risk factors, GBPS ejection fraction (EF), and cumulative anthracycline dose were collected. Results From 1 August 2009 to 31 July 2012, 179 patients underwent GBPS pre-doxorubicin chemotherapy. The mean age was 59 years (range 21-89 years), with 51% being males. Only two patients (1.1%) had an abnormal EF < 50%, while 33 patients (18%) had an EF 51-59% and 144 patients (80%) had EF ≥ 60%. The two patients with reduced baseline EF still received anthracycline-based chemotherapy. All 135 patients without any known cardiovascular risk factors had normal EFs. The total number of patients who received anthracycline chemotherapy during the same period was 207. Thus 28 patients (13%) commenced anthracycline without a prior GBPS. Conclusion Only 1.1% of the screened patients had EF < 50%. These two patients still received doxorubicin chemotherapy despite a compromised EF, as their treating clinicians believed that the benefits of chemotherapy outweighed the risk of potential cardiac toxicity. Our audit questions the practice of routine cardiac evaluation pre-anthracycline screening with GBPS. We propose that routine screening only be requested if cardiac risk factors are present.


Assuntos
Antraciclinas/efeitos adversos , Antibióticos Antineoplásicos/efeitos adversos , Cardiotoxicidade/sangue , Cardiotoxicidade/prevenção & controle , Leucemia Mielogênica Crônica BCR-ABL Positiva/sangue , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antraciclinas/administração & dosagem , Antibióticos Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Feminino , Cardiopatias/sangue , Cardiopatias/induzido quimicamente , Cardiopatias/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Volume Sistólico/efeitos dos fármacos , Volume Sistólico/fisiologia , Adulto Jovem
4.
Gene Ther ; 23(4): 330-9, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26752352

RESUMO

For ethical and safety reasons it is critical to develop easily implemented assays with high sensitivity and specificity for gene doping surveillance. Two nested quantitative real-time PCR (qPCR) assays were developed that target the human EPO (hEPO) cDNA sequence in a circular form, representative of recombinant adeno-associated viral (rAAV) vector genomes found in vivo. Through an interlaboratory evaluation, the assays were validated and utilized in an in vitro blinded study. These assays are specific and extremely sensitive with a limit of detection (LOD) of 1 copy of circular plasmid DNA and a limit of quantification (LOQ) of 10 to 20 copies in the presence of 500 ng of human genomic DNA (hgDNA) extracted from WBCs. Additionally, using the two nested qPCR assays in a non-human primate study, where macaques were injected intramuscularly with a rAAV8 vector harboring a promoterless hEPO cDNA sequence, the viral vector was detected 8 to 14 weeks post-injection in macaque WBCs. The high sensitivity of the nested qPCR approach along with the capability of quantifying target DNA, make this approach a reliable tool for gene doping surveillance and the monitoring of exogenous DNA sequences.


Assuntos
Eritropoetina/genética , Reação em Cadeia da Polimerase/métodos , Transgenes , Animais , DNA/sangue , DNA/genética , DNA/isolamento & purificação , Dopagem Esportivo/prevenção & controle , Eritropoetina/análise , Eritropoetina/sangue , Vetores Genéticos , Humanos , Macaca , Macaca fascicularis , Masculino , Plasmídeos/genética , Reação em Cadeia da Polimerase em Tempo Real , Sensibilidade e Especificidade
5.
Diabet Med ; 31(9): 1069-77, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24867069

RESUMO

AIMS: Among people with diabetes, 10-25% will experience a foot ulcer. Research has shown that supplementation with arginine, glutamine and ß-hydroxy-ß-methylbutyrate may improve wound repair. This study tested whether such supplementation would improve healing of foot ulcers in persons with diabetes. METHODS: Along with standard of care, 270 subjects received, in a double-blinded fashion, (twice per day) either arginine, glutamine and ß-hydroxy-ß-methylbutyrate or a control drink for 16 weeks. The proportion of subjects with total wound closure and time to complete healing was assessed. In a post-hoc analysis, the interaction of serum albumin or limb perfusion, as measured by ankle-brachial index, and supplementation on healing was investigated. RESULTS: Overall, there were no group differences in wound closure or time to wound healing at week 16. However, in subjects with an albumin level of ≤ 40 g/l and/or an ankle-brachial index of < 1.0, a significantly greater proportion of subjects in the arginine, glutamine and ß-hydroxy-ß-methylbutyrate group healed at week 16 compared with control subjects (P = 0.03 and 0.008, respectively). Those with low albumin or decreased limb perfusion in the supplementation group were 1.70 (95% CI 1.04-2.79) and 1.66 (95% CI 1.15-2.38) times more likely to heal. CONCLUSIONS: While no differences in healing were identified with supplementation in non-ischaemic patients or those with normal albumin, addition of arginine, glutamine and ß-hydroxy-ß-methylbutyrate as an adjunct to standard of care may improve healing of diabetic foot ulcers in patients with risk of poor limb perfusion and/or low albumin levels. Further investigation involving arginine, glutamine and ß-hydroxy-ß-methylbutyrate in these high-risk subgroups might prove clinically valuable.


Assuntos
Arginina/administração & dosagem , Pé Diabético/fisiopatologia , Suplementos Nutricionais , Glutamina/administração & dosagem , Valeratos/administração & dosagem , Cicatrização , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice Tornozelo-Braço , Pé Diabético/dietoterapia , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
6.
Osteoporos Int ; 24(7): 2105-14, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23334732

RESUMO

UNLABELLED: We report the results of alendronate ingestion plus exercise in preventing the declines in bone mass and strength and elevated levels of urinary calcium and bone resorption in astronauts during 5.5 months of spaceflight. INTRODUCTION: This investigation was an international collaboration between NASA and the JAXA space agencies to investigate the potential value of antiresorptive agents to mitigate the well-established bone changes associated with long-duration spaceflight. METHODS: We report the results from seven International Space Station (ISS) astronauts who spent a mean of 5.5 months on the ISS and who took an oral dose of 70 mg of alendronate weekly starting 3 weeks before flight and continuing throughout the mission. All crewmembers had available for exercise a treadmill, cycle ergometer, and a resistance exercise device. Our assessment included densitometry of multiple bone regions using X-ray absorptiometry (DXA) and quantitative computed tomography (QCT) and assays of biomarkers of bone metabolism. RESULTS: In addition to pre- and post-flight measurements, we compared our results to 18 astronauts who flew ISS missions and who exercised using an early model resistance exercise device, called the interim resistance exercise device, and to 11 ISS astronauts who exercised using the newer advanced resistance exercise device (ARED). Our findings indicate that the ARED provided significant attenuation of bone loss compared with the older device although post-flight decreases in the femur neck and hip remained. The combination of the ARED and bisphosphonate attenuated the expected decline in essentially all indices of altered bone physiology during spaceflight including: DXA-determined losses in bone mineral density of the spine, hip, and pelvis, QCT-determined compartmental losses in trabecular and cortical bone mass in the hip, calculated measures of fall and stance computed bone strength of the hip, elevated levels of bone resorption markers, and urinary excretion of calcium. CONCLUSIONS: The combination of exercise plus an antiresoptive drug may be useful for protecting bone health during long-duration spaceflight.


Assuntos
Alendronato/uso terapêutico , Conservadores da Densidade Óssea/uso terapêutico , Terapia por Exercício/métodos , Osteoporose/prevenção & controle , Voo Espacial , Absorciometria de Fóton/métodos , Adulto , Alendronato/administração & dosagem , Biomarcadores/sangue , Biomarcadores/urina , Composição Corporal/fisiologia , Densidade Óssea/efeitos dos fármacos , Densidade Óssea/fisiologia , Conservadores da Densidade Óssea/administração & dosagem , Reabsorção Óssea/etiologia , Reabsorção Óssea/prevenção & controle , Terapia Combinada , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/etiologia , Osteoporose/fisiopatologia , Ausência de Peso/efeitos adversos
7.
Nat Genet ; 16(3): 270-6, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9207793

RESUMO

Haemophilia B, or factor IX deficiency, is a X-linked recessive disorder that occurs in about one in 25,000 males, and severely affected people are at risk for spontaneous bleeding into numerous organs. Bleeding can be life-threatening or lead to chronic disabilities with haemophilic arthropathy. The severity of the bleeding tendency varies among patients and is related to the concentration of functional plasma factor IX. Patients with 5-30% of the normal factor IX have mild haemophilia that may not be recognized until adulthood or after heavy trauma or surgery. Therapy for acute bleeding consists of the transfusion of clotting-factor concentrates prepared from human blood and recombinant clotting factors that are currently in clinical trials. Both recombinant retroviral and adenoviral vectors have successfully transferred factor IX cDNA into the livers of dogs with haemophilia B. Recombinant retroviral-mediated gene transfer results in persistent yet subtherapeutic concentrations of factor IX and requires the stimulation of hepatocyte replication before vector administration. Recombinant adenoviral vectors can temporarily cure the coagulation defect in the canine haemophilia B model; however, an immune response directed against viral gene products made by the vector results in toxicity and limited gene expression. The use of recombinant adeno-associated virus (rAAV) vectors is promising because the vector contains no viral genes and can transduce non-dividing cells. The efficacy of in vivo transduction of non-dividing cells has been demonstrated in a wide variety of tissues. In this report, we describe the successful transduction of the liver in vivo using r-AAV vectors delivered as a single administration to mice and demonstrate that persistent, curative concentrations of functional human factor IX can be achieved using wild-type-free and adenovirus-free rAAV vectors. This demonstrates the potential of treating haemophilia B by gene therapy at the natural site of factor IX production.


Assuntos
Dependovirus/genética , Fator IX/genética , Técnicas de Transferência de Genes , Vetores Genéticos , Hemofilia B/terapia , Fígado/metabolismo , Alanina Transaminase/sangue , Alanina Transaminase/metabolismo , Animais , Divisão Celular , DNA Antissenso/genética , DNA Antissenso/metabolismo , Fator IX/metabolismo , Expressão Gênica , Terapia Genética , Hemofilia B/genética , Humanos , Imuno-Histoquímica , Hibridização In Situ , Camundongos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Tirosina 3-Mono-Oxigenase/genética , Tirosina 3-Mono-Oxigenase/metabolismo
8.
Eur J Gynaecol Oncol ; 33(2): 183-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22611960

RESUMO

PURPOSE: To compare physician and nurse practitioner accuracy in recognizing cervical dysplasia during colposcopy. MATERIALS AND METHODS: A retrospective review was performed of cervical excisional biopsies from 2007 to 2009 performed by gynecologists and nurse practitioners in the same patient population. Cervical cone biopsy and loop electrosurgical excision procedure (LEEP) pathology were used as a gold standard compared to the previous colposcopy biopsies. RESULTS: Four hundred fifty-five patients qualified for the study. Patients were stratified according to age: under 30 years, 30-39, and 40 and above. For physicians, 77% of high-grade colposcopy biopsy results agreed with high-grade pathology on cone biopsy or LEEP. This was statistically similar to nurse practitioner results (p = 0.12). Likewise, there was no significant difference between physician and nurse practitioner accuracy within the various patient age strata. CONCLUSION: Colposcopy biopsy results compared to cone biopsy or LEEP results were statistically similar between gynecologists and nurse practitioners.


Assuntos
Colo do Útero/patologia , Competência Clínica , Colposcopia/normas , Profissionais de Enfermagem/estatística & dados numéricos , Médicos/estatística & dados numéricos , Displasia do Colo do Útero/diagnóstico , Adolescente , Adulto , Idoso , Biópsia , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo , Displasia do Colo do Útero/patologia , Adulto Jovem
9.
Gene Ther ; 18(7): 709-18, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21390073

RESUMO

Legitimate uses of gene transfer technology can benefit from sensitive detection methods to determine vector biodistribution in pre-clinical studies and in human clinical trials, and similar methods can detect illegitimate gene transfer to provide sports-governing bodies with the ability to maintain fairness. Real-time PCR assays were developed to detect a performance-enhancing transgene (erythropoietin, EPO) and backbone sequences in the presence of endogenous cellular sequences. In addition to developing real-time PCR assays, the steps involved in DNA extraction, storage and transport were investigated. By real-time PCR, the vector transgene is distinguishable from the genomic DNA sequence because of the absence of introns, and the vector backbone can be identified by heterologous gene expression control elements. After performance of the assays was optimized, cynomolgus macaques received a single dose by intramuscular (IM) injection of plasmid DNA, a recombinant adeno-associated viral vector serotype 1 (rAAV1) or a rAAV8 vector expressing cynomolgus macaque EPO. Macaques received a high plasmid dose intended to achieve a significant, but not life-threatening, increase in hematocrit. rAAV vectors were used at low doses to achieve a small increase in hematocrit and to determine the limit of sensitivity for detecting rAAV sequences by single-step PCR. DNA extracted from white blood cells (WBCs) was tested to determine whether WBCs can be collaterally transfected by plasmid or transduced by rAAV vectors in this context, and can be used as a surrogate marker for gene doping. We demonstrate that IM injection of a conventional plasmid and rAAV vectors results in the presence of DNA that can be detected at high levels in blood before rapid elimination, and that rAAV genomes can persist for several months in WBCs.


Assuntos
DNA Viral/sangue , Dependovirus/genética , Dopagem Esportivo , Eritropoetina/sangue , Eritropoetina/genética , Vetores Genéticos , Farmacocinética , Plasmídeos/sangue , Transgenes , Animais , Sistemas Computacionais , DNA/sangue , Técnicas de Transferência de Genes , Injeções Intramusculares , Leucócitos/química , Macaca fascicularis , Reação em Cadeia da Polimerase , Fatores de Tempo
10.
Ann Oncol ; 22(9): 1981-1987, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21282282

RESUMO

BACKGROUND: The benefit of adjuvant chemotherapy in postmenopausal patients with estrogen receptor (ER)-positive lymph node-negative breast cancer is being reassessed. PATIENTS AND METHODS: After stratification by ER status, 1669 postmenopausal patients with operable lymph node-negative breast cancer were randomly assigned to three 28-day courses of 'classical' CMF (cyclophosphamide, methotrexate, 5-fluorouracil) chemotherapy followed by tamoxifen for 57 months (CMF→tamoxifen) or to tamoxifen alone for 5 years. RESULTS: ERs were positive in 81% of tumors. At a median follow-up of 13.1 years, patients with ER-positive breast cancers did not benefit from CMF [13-year disease-free survival (DFS) 64% CMF→tamoxifen, 66% tamoxifen; P = 0.99], whereas CMF substantially improved the prognosis of patients with ER-negative breast cancer (13-year DFS 73% versus 57%, P = 0.001). Similarly, breast cancer-free interval (BCFI) was identical in the ER-positive cohort but significantly improved by chemotherapy in the ER-negative cohort (13-year BCFI 80% versus 63%, P = 0.001). CMF had no influence on second nonbreast malignancies or deaths from other causes. CONCLUSION: CMF is not beneficial in postmenopausal patients with node-negative ER-positive breast cancer but is highly effective within the ER-negative cohort. In the future, other markers of chemotherapy response may define a subset of patients with ER-positive tumors who may benefit from adjuvant chemotherapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Receptores de Estrogênio/biossíntese , Idoso , Neoplasias da Mama/patologia , Ciclofosfamida/administração & dosagem , Esquema de Medicação , Feminino , Fluoruracila/administração & dosagem , Seguimentos , Humanos , Metástase Linfática , Metotrexato/administração & dosagem , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Prospectivos , Tamoxifeno/administração & dosagem
11.
Nat Med ; 5(1): 64-70, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9883841

RESUMO

Hemophilia B, or factor IX deficiency, is an X-linked recessive disorder occurring in about 1 in 25,000 males. Affected individuals are at risk for spontaneous bleeding into many organs; treatment mainly consists of the transfusion of clotting factor concentrates prepared from human blood or recombinant sources after bleeding has started. Small- and large-animal models have been developed and/or characterized that closely mimic the human disease state. As a preclinical model for gene therapy, recombinant adeno-associated viral vectors containing the human or canine factor IX cDNAs were infused into the livers of murine and canine models of hemophilia B, respectively. There was no associated toxicity with infusion in either animal model. Constitutive expression of factor IX was observed, which resulted in the correction of the bleeding disorder over a period of over 17 months in mice. Mice with a steady-state concentration of 25% of the normal human level of factor IX had normal coagulation. In hemophilic dogs, a dose of rAAV that was approximately 1/10 per body weight that given to mice resulted in 1% of normal canine factor IX levels, the absence of inhibitors, and a sustained partial correction of the coagulation defect for at least 8 months.


Assuntos
Dependovirus , Fator IX/genética , Terapia Genética , Vetores Genéticos , Hemofilia B/terapia , Animais , Anticorpos/sangue , Tempo de Sangramento , Transformação Celular Viral , Modelos Animais de Doenças , Cães , Humanos , Fígado , Camundongos , Camundongos Endogâmicos C57BL , Recombinação Genética
12.
Poult Sci ; 100(1): 110-118, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33357673

RESUMO

Coccidiosis, the parasitic disease caused by Eimeria spp., is controlled during broiler chicken production through the inclusion of in-feed anticoccidial medications. Live-coccidiosis vaccination has become an increasingly common alternative to these medications. Monitoring infections with Eimeria spp. in flocks can be accomplished through determining the concentration of oocysts excreted in the fecal material (i.e., oocysts per gram; OPG). The purpose of our study was to sample commercial Ontario broiler chicken flocks at various times of the year to determine weekly OPG counts for flocks that use either an in-feed anticoccidial medication or a live-coccidiosis vaccine. Weekly sampling of 95 flocks from placement to market permitted documentation of oocyst cycling patterns typical of conventional and antibiotic-free flocks, and variation of these patterns in summer and winter. Medicated flocks had higher and later peak oocyst shedding compared with vaccinated flocks. Flocks reared in the summer peaked in oocyst shedding earlier than flocks reared in the winter. Despite what appears to be poorer coccidiosis control in the medicated flocks, the performance data were similar for these flocks compared with vaccinated flocks. This is the first study describing typical patterns of parasite shedding in Ontarian commercial broiler chicken flocks; these data will provide a baseline of expected Eimeria spp. infections in Canadian broiler chicken flocks to ensure optimal coccidiosis prevention.


Assuntos
Coccidiose , Monitoramento Epidemiológico , Oocistos , Doenças das Aves Domésticas , Vacinas Protozoárias , Animais , Galinhas/imunologia , Coccidiose/diagnóstico , Coccidiose/prevenção & controle , Coccidiose/veterinária , Coccidiostáticos/uso terapêutico , Monitoramento Epidemiológico/veterinária , Ontário/epidemiologia , Doenças das Aves Domésticas/diagnóstico , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/prevenção & controle , Vacinação/veterinária
13.
Vet Parasitol ; 296: 109443, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34147767

RESUMO

DNA-based diagnostic assays for detecting infections with Eimeria species have been limited to providing identification and presence/absence data for samples containing oocysts. Modern technologies that generate quantitative data, such as droplet digital PCR (ddPCR) and Next Generation Sequencing (NGS), utilize a relatively short amplicon size containing sufficient species-specific variation for reliable species level identification. Targeting the cytochrome c oxidase subunit III gene in the mitochondrial genome, we established protocols using these technologies to determine the relative abundance of the number of copies/µL of Eimeria species in a sample. Samples from chickens of known and unknown Eimeria species composition were analyzed to determine the suitability of these technologies as diagnostic assays. All technologies demonstrated robust capability of identifying and quantifying the Eimeria species in samples. The new quantitative assays described herein will produce invaluable detail of Eimeria species infections for an array of situations in commercial chicken production systems, enabling further characterization of the disease profile and allowing for the development or enhancement of new intervention strategies.


Assuntos
Coccidiose , DNA , Eimeria , Sequenciamento de Nucleotídeos em Larga Escala , Doenças das Aves Domésticas , Animais , Galinhas , Coccidiose/parasitologia , Coccidiose/veterinária , DNA/análise , DNA/química , Eimeria/genética , Sequenciamento de Nucleotídeos em Larga Escala/veterinária , Reação em Cadeia da Polimerase/veterinária , Doenças das Aves Domésticas/parasitologia
14.
Poult Sci ; 100(2): 663-674, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33518120

RESUMO

Increasing resistance of Eimeria species to anticoccidial medications is an issue in the broiler chicken industry. Using drug-sensitive strains in live-coccidiosis vaccines has been shown to improve anticoccidial effectiveness in US-based broiler production. In Canada, litter is removed between flocks, which differ from the US industry practice. Thus, we investigated the use of drug-sensitive vaccine strains in a Canadian broiler production facility with suspected anticoccidial resistance. Weekly fecal samples were collected from flocks before, during, and after vaccine seeding to determine oocyst shedding patterns; following the vaccine seeding, OPG counts from similar aged birds were lower than flocks before live-coccidiosis vaccine use. Eimeria species isolates, collected before and after vaccine seeding, were used in 2 anticoccidial sensitivity tests to evaluate their susceptibility to commercially available anticoccidial medications; a low-dose challenge to define parasite replication, and a high-dose challenge to monitor broiler performance. In both experiments, isolates collected after seeding were more susceptible to almost every anticoccidial medication evaluated compared with the isolates collected before seeding. These results demonstrate an improvement in sensitivity to many anticoccidials after the use of live-coccidiosis vaccines at this facility. However, the regulated removal of litter at the end of each flock required under Canadian broiler chicken production management rules could limit the establishment of vaccine-strain Eimeria species in broiler facilities and could shorten the longevity of improved drug sensitivity observed in this study.


Assuntos
Galinhas , Coccidiose/veterinária , Coccidiostáticos/farmacologia , Eimeria/efeitos dos fármacos , Doenças das Aves Domésticas/tratamento farmacológico , Vacinas Protozoárias , Animais , Canadá , Coccidiose/tratamento farmacológico , Coccidiose/prevenção & controle , Coccidiostáticos/uso terapêutico , Eimeria/imunologia , Fezes/parasitologia , Masculino , Doenças das Aves Domésticas/prevenção & controle , Distribuição Aleatória
15.
Nano Lett ; 9(11): 3877-82, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19757858

RESUMO

We demonstrate the growth of phosphorus doped Zn(1-x)Mg(x)O nanowire (NW) using pulsed laser deposition. For the first time, p-type Zn(0.92)Mg(0.08)O:P NWs are likely obtained in reference to atomic force microscopy based piezoelectric output measurements, X-ray photoelectron spectroscopy, and the transport property between the NWs and a n-type ZnO film. A shallow acceptor level of approximately 140 meV is identified by temperature-dependent photoluminescence. A piezoelectric output of 60 mV on average has been received using the doped NWs. Besides a control on NW aspect ratio and density, band gap engineering has also been achieved by alloying with Mg to a content of x = 0.23. The alloyed NWs with controllable conductivity type have potential application in high-efficiency all-ZnO NWs based LED, high-output ZnO nanogenerator, and other optical or electrical devices.

16.
Ann Oncol ; 20(11): 1813-7, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19553291

RESUMO

BACKGROUND: Acquired and de novo endocrine resistance in breast cancer (BC) may be associated with overexpression of epidermal growth factor receptor (EGFR). Gefinitib is an orally active selective EGFR inhibitor which might benefit advanced breast cancer (ABC) patients either with acquired hormone resistance or with hormone receptor (HR)-negative tumors. PATIENTS AND METHODS: A two-arm multicenter phase II trial of oral gefitinib 500 mg/day was planned in two groups of 45 patients with ABC for whom chemotherapy was not currently indicated. Group 1 had hormone-resistant BC defined as HR-positive BC with progression after treatment with tamoxifen and an aromatase inhibitor. Group 2 had HR-negative BC. Tumor response was assessed every 8 weeks. The primary end point was the clinical benefit rate (CBR). RESULTS: Forty patients with hormone-resistant BC had a CBR of 0%. Two of 25 HR-negative BC patients showed stable disease (less than a 50% reduction and less than a 25% increase in the sum of the products of two perpendicular diameters of all measured lesions and the appearance of no new lesions) at 24 weeks resulting in a CBR of 7.7% (95% CI 0.9% to 25.1%). Enrollment ceased due to the low CBR. Toxicity resulted in treatment interruption (46%), dose reduction (20%) and withdrawal (11%) of patients. CONCLUSION: At a dose of 500 mg/day, gefitinib monotherapy resulted in a low CBR and no tumor response was identified.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Quinazolinas/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/metabolismo , Receptores ErbB/antagonistas & inibidores , Feminino , Gefitinibe , Humanos , Pessoa de Meia-Idade , Receptores de Estrogênio/biossíntese , Receptores de Progesterona/biossíntese
17.
Science ; 160(3826): 427-8, 1968 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-5644044

RESUMO

Dimethyl sulfoxide (DMSO) enhanced the hypertaurinuria produced by benzene, chlorobenzene, and toluene in rats. Undiluted DMSO was more effective than DMSO diluted with water in potentiating the toxicity of benzene in both rats and mice. Supernatants (9000g) prepared from livers of rats treated with DMSO 24 hours earlier metabolized more benzene than those from control rats.


Assuntos
Benzeno/toxicidade , Dimetil Sulfóxido/farmacologia , Hidrocarbonetos Halogenados/toxicidade , Tolueno/toxicidade , Animais , Benzeno/metabolismo , Isótopos de Carbono , Sinergismo Farmacológico , Fígado/efeitos dos fármacos , Fígado/metabolismo , Ratos , Taurina/urina
18.
Science ; 214(4517): 188-90, 1981 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-17734001

RESUMO

Crystals of n-alkanes show a remarkable series of solid-solid phase transitions. In the odd n-alkanes C(25), C(27), and C(29) a previously unknown transition is found by both calorimetry and infrared spectroscopy. The ubiquitous presence of nonplanar conformations of the chains is shown by infrared spectroscopy. The nonplanar conformers constitute approximately half the molecules in the highest temperature solid phase of C(29).

19.
Science ; 246(4930): 651-4, 1989 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-2510297

RESUMO

The crystals of most proteins or other biological macromolecules are poorly ordered and diffract to lower resolutions than those observed for most crystals of simple organic and inorganic compounds. Crystallization in the microgravity environment of space may improve crystal quality by eliminating convection effects near growing crystal surfaces. A series of 11 different protein crystal growth experiments was performed on U.S. space shuttle flight STS-26 in September 1988. The microgravity-grown crystals of gamma-interferon D1, porcine elastase, and isocitrate lyase are larger, display more uniform morphologies, and yield diffraction data to significantly higher resolutions than the best crystals of these proteins grown on Earth.


Assuntos
Proteínas , Ausência de Peso , Animais , Cristalização , Interferon gama , Isocitrato Liase , Elastase Pancreática , Voo Espacial , Suínos
20.
Artigo em Inglês | MEDLINE | ID: mdl-19412856

RESUMO

Mutagenicity and carcinogenicity are endpoints of major environmental and regulatory concern. These endpoints are also important targets for development of alternative methods for screening and prediction due to the large number of chemicals of potential concern and the tremendous cost (in time, money, animals) of rodent carcinogenicity bioassays. Both mutagenicity and carcinogenicity involve complex, cellular processes that are only partially understood. Advances in technologies and generation of new data will permit a much deeper understanding. In silico methods for predicting mutagenicity and rodent carcinogenicity based on chemical structural features, along with current mutagenicity and carcinogenicity data sets, have performed well for local prediction (i.e., within specific chemical classes), but are less successful for global prediction (i.e., for a broad range of chemicals). The predictivity of in silico methods can be improved by improving the quality of the data base and endpoints used for modelling. In particular, in vitro assays for clastogenicity need to be improved to reduce false positives (relative to rodent carcinogenicity) and to detect compounds that do not interact directly with DNA or have epigenetic activities. New assays emerging to complement or replace some of the standard assays include Vitotox, GreenScreenGC, and RadarScreen. The needs of industry and regulators to assess thousands of compounds necessitate the development of high-throughput assays combined with innovative data-mining and in silico methods. Various initiatives in this regard have begun, including CAESAR, OSIRIS, CHEMOMENTUM, CHEMPREDICT, OpenTox, EPAA, and ToxCast. In silico methods can be used for priority setting, mechanistic studies, and to estimate potency. Ultimately, such efforts should lead to improvements in application of in silico methods for predicting carcinogenicity to assist industry and regulators and to enhance protection of public health.


Assuntos
Carcinógenos/toxicidade , Modelos Biológicos , Modelos Químicos , Mutagênicos/toxicidade , Relação Quantitativa Estrutura-Atividade , Animais , Carcinógenos/química , Sistemas Inteligentes , Previsões/métodos , Humanos , Mutagênicos/química , Medição de Risco , Roedores
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