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1.
Sci Rep ; 9(1): 6527, 2019 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-31024053

RESUMO

Southern flounder (Paralichthys lethostigma) exhibit environmental sex determination (ESD), where environmental factors can influence phenotypic sex during early juvenile development but only in the presumed XX female genotype. Warm and cold temperatures masculinize fish with mid-range conditions producing at most 50% females. Due to sexually dimorphic growth, southern flounder fisheries are dependent upon larger females. Wild populations could be at risk of masculinization from ESD due to globally increasing water temperatures. We evaluated the effects of habitat and temperature on wild populations of juvenile southern flounder in North Carolina, USA. While northern habitats averaged temperatures near 23 °C and produced the greatest proportion of females, more southerly habitats exhibited warmer temperatures (>27 °C) and consistently produced male-biased sex ratios (up to 94% male). Rearing flounder in the laboratory under temperature regimes mimicking those of natural habitats recapitulated sex ratio differences observed across the wild populations, providing strong evidence that temperature is a key factor influencing sex ratios in nursery habitats. These studies provide evidence of habitat conditions interacting with ESD to affect a key demographic parameter in an economically important fishery. The temperature ranges that yield male-biased sex ratios are within the scope of predicted increases in ocean temperature under climate change.


Assuntos
Animais Selvagens/fisiologia , Peixes/fisiologia , Temperatura Alta , Processos de Determinação Sexual , Animais , Ecossistema , Feminino , Peixes/anatomia & histologia , Gônadas/metabolismo , Masculino , North Carolina , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Razão de Masculinidade , Água
2.
J Dairy Sci ; 98(9): 6270-7, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26188576

RESUMO

Development and use of on-farm assays to detect antimicrobial residues in milk is important to reduce the risk of violative residues in marketed milk. The objective of this study was to evaluate the effectiveness of a lateral-flow immunodiagnostic assay (BetaStar Plus, Neogen Corp., Lansing, MI) in detecting ceftiofur residues in milk from individual cows treated for mastitis. This assay is currently approved by the US Federal Drug Administration (FDA) for detecting ß-lactam residues in commingled milk. Forty-five dairy cows with clinical mastitis from 4 dairy farms were enrolled and treated intramammary with 125 mg of ceftiofur hydrochloride (Spectramast LC, Zoetis, Madison, NJ) according to the manufacturer's label recommendation. Composite milk samples were collected (A) before first intramammary antimicrobial treatment, (B) before the last intramammary antimicrobial treatment, (C) the last milking of the product-labeled milk withhold, (D) the first milking after the product-labeled milk withhold had been met, and (E) 72 h after the product-labeled milk withhold had been met. Samples were tested using the BetaStar Plus assay within 48 h of collection. Parallel samples were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and for somatic cell count and milk components. The BetaStar Plus assay identified 6.7, 60.0, 46.7, 22.2, and 6.7% positive samples at each of the respective time points. The assay had sensitivity and specificity of 100 and 84.7%, respectively, compared with liquid chromatography-tandem mass spectrometry analysis using FDA published residue tolerance levels for ceftiofur (or ceftiofur metabolites) as a threshold. The BetaStar Plus assay could be useful for detecting ceftiofur residues in milk from individual cows following intramammary treatment for mastitis before the milk is shipped for processing.


Assuntos
Antibacterianos/análise , Bioensaio/métodos , Cefalosporinas/análise , Resíduos de Drogas/análise , Mastite Bovina/tratamento farmacológico , Leite/química , Animais , Antibacterianos/uso terapêutico , Bovinos , Contagem de Células , Cefalosporinas/uso terapêutico , Cromatografia Líquida , Feminino , Espectrometria de Massas em Tandem
3.
J Oral Rehabil ; 38(1): 72-8, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20626573

RESUMO

The aim of this project was to examine tooth preparations made by general dental practitioners (GDPs) for occlusal and cingulum rest seats for cobalt-chromium removable partial dentures (RPDs). Master casts and prescribed denture designs for cobalt-chromium RPDs produced by a commercial dental laboratory from impressions made by 45 GDPs across Wales were evaluated over a period of 5 months. Rest seats and associated interocclusal clearances were assessed using pre-determined criteria. A total of 68 casts were examined. Of these, 33 did not have rest seats included in their prescription. Of the remaining 35 casts, 81 rests had been prescribed of which only 24 (30%) had signs of tooth preparations for these rest seats. Using pre-determined criteria, 60% of rest seats were under-prepared in the mesio-distal plane and 30% were over-prepared in the bucco-lingual plane. In 17 cases where natural teeth opposed the rest seat, the mean interocclusal clearance was 1·5 mm (range 0·6-3·5 mm) with 6 of the 17 rests (35%) being less than the recommended thickness. In total, 18 of the 24 rests prepared did not meet the criteria, and 11 of the 21 rests prescribed had no obvious preparation and insufficient occlusal clearance. Where prescribed, the majority of rests did not meet the identified criteria. The rest seat preparations varied greatly in all planes including the interocclusal clearance. Further emphasis should be given to aspects of denture design in undergraduate and continuing education programmes for dentists.


Assuntos
Prótese Parcial Removível , Odontologia Geral , Preparo Prostodôntico do Dente/métodos , Cromo , Cobalto , Dente Suporte , Análise do Estresse Dentário , Planejamento de Dentadura , Retenção de Dentadura/métodos , Humanos , Modelos Dentários
4.
Anim Health Res Rev ; 8(2): 117-28, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18218156

RESUMO

Mannheimia haemolytica is the principal bacterium isolated from respiratory disease in feedlot cattle and is a significant component of enzootic pneumonia in all neonatal calves. A commensal of the nasopharynx, M. haemolytica is an opportunist, gaining access to the lungs when host defenses are compromised by stress or infection with respiratory viruses or mycoplasma. Although several serotypes act as commensals, A1 and A6 are the most frequent isolates from pneumonic lungs. Potential virulence factors include adhesin, capsular polysaccharide, fimbriae, iron-regulated outer membrane proteins, leukotoxin (Lkt), lipopolysaccharide (LPS), lipoproteins, neuraminidase, sialoglycoprotease and transferrin-binding proteins. Of these, Lkt is pivotal in induction of pneumonia. Lkt-mediated infiltration and destruction of neutrophils and other leukocytes impairs bacterial clearance and contributes to development of fibrinous pneumonia. LPS may act synergistically with Lkt, enhancing its effects and contributing endotoxic activity. Antibiotics are employed extensively in the feedlot industry, both prophylactically and therapeutically, but their efficacy varies because of inconsistencies in diagnosis and treatment regimes and development of antibiotic resistance. Vaccines have been used for many decades, even though traditional bacterins failed to demonstrate protection and their use often enhanced disease in vaccinated animals. Modern vaccines use culture supernatants containing Lkt and other soluble antigens, or bacterial extracts, alone or combined with bacterins. These vaccines have 50-70% efficacy in prevention of M. haemolytica pneumonia. Effective control of M. haemolytica pneumonia is likely to require a combination of more definitive diagnosis, efficacious vaccines, therapeutic intervention and improved management practices.


Assuntos
Vacinas Bacterianas/imunologia , Complexo Respiratório Bovino/epidemiologia , Complexo Respiratório Bovino/microbiologia , Mannheimia haemolytica/patogenicidade , Criação de Animais Domésticos/métodos , Animais , Animais Recém-Nascidos , Complexo Respiratório Bovino/prevenção & controle , Bovinos , Exotoxinas/imunologia , Pneumonia Enzoótica dos Bezerros/epidemiologia , Pneumonia Enzoótica dos Bezerros/microbiologia , Pneumonia Enzoótica dos Bezerros/prevenção & controle , Fatores de Risco , Sorotipagem/veterinária
5.
J Chem Ecol ; 29(5): 1073-82, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12857022

RESUMO

Euphorbia esula, common name leafy spurge, was chemically evaluated for aversive phytochemicals that appear to minimize herbivory by rodents and cattle. A middle-layer extract elicited food aversions in rats as did the petroleum ether extract of the initial methanol extract. Kaempferol-3-0-beta-glucuronic acid and quercetin-3-0-beta-glucuronic acid were separated and identified from the middle-layer residue. This study is the first report of quercetin-3-0-beta-glucuronic acid in leafy spurge. Together these flavonoidal glucosides were mildly aversive to rats but showed less aversive activity when tested separately. The middle-layer extract produced no aversive response from cattle, while the petroleum ether extract elicited strong aversions in cattle. Flavonoidal compounds from leafy spurge that were aversive to rats, a monogastric mammal, were not aversive to cattle, a ruminant. Microbial degradation of the compounds before they reach the intestines and are absorbed into the bloodstream is likely a key advantage for cattle compared to rats.


Assuntos
Euphorbia/química , Comportamento Alimentar , Flavonoides/farmacologia , Animais , Bovinos , Flavonoides/metabolismo , Extratos Vegetais/farmacologia , Folhas de Planta , Ratos
6.
Phys Rev E Stat Nonlin Soft Matter Phys ; 64(2 Pt 1): 021401, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11497576

RESUMO

Smectites are a group of 2:1-layer phyllosilicate minerals that have been extensively studied by small-angle x-ray scattering (SAXS) because of their industrial and environmental significance. In previous studies, a Guinier plot has been used to obtain the radius of gyration of the clay particles, from which geometric information of the particle structure is derived. Using an indirect Fourier transform to treat SAXS data from a dilute montmorillonite suspension, a negative electron contrast at the clay-water interface is observed. This electron inhomogeneity has violated the assumption underlying the application of the Guinier plot, which requires particles to have a uniform electron density. The presence of this inhomogeneity explains the inability of previous studies to correctly determine particle dimensions using the Guinier plot. Using this model of the clay-water interface, a modified Guinier plot has been derived and was experimentally verified. The calculation shows the presence of negative electron contrast at montmorillonite-water interfaces, which is in accordance with the results from the indirect Fourier transform method. This approximation has the potential to predict the geometric information for similar colloids studied by small-angle scattering.

7.
Biometrics ; 57(1): 253-9, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11252607

RESUMO

We propose a method of analyzing collections of related curves in which the individual curves are modeled as spline functions with random coefficients. The method is applicable when the individual curves are sampled at variable and irregularly spaced points. This produces a low-rank, low-frequency approximation to the covariance structure, which can be estimated naturally by the EM algorithm. Smooth curves for individual trajectories are constructed as best linear unbiased predictor (BLUP) estimates, combining data from that individual and the entire collection. This framework leads naturally to methods for examining the effects of covariates on the shapes of the curves. We use model selection techniques--Akaike information criterion (AIC), Bayesian information criterion (BIC), and cross-validation--to select the number of breakpoints for the spline approximation. We believe that the methodology we propose provides a simple, flexible, and computationally efficient means of functional data analysis.


Assuntos
Biometria , Modelos Estatísticos , Algoritmos , Teorema de Bayes , Contagem de Linfócito CD4/estatística & dados numéricos , Simulação por Computador , Interpretação Estatística de Dados , Marcha , Humanos , Modelos Lineares
8.
Anal Chem ; 72(2): 384-90, 2000 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-10658334

RESUMO

Fulvic acid (FA) is a heterogeneous mixture of organic macromolecules found in the waters, soils, and sediments of the earth's surface. The ability of electrospray ionization (ESI) to effectively transfer large ions from the solution phase to the gas phase and the coupling of ESI to the high-mass-resolution capabilities of Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) provide a potential method for the mass spectrometric analysis of FA. Positive- and negative-ion ESI FT-ICR MS analyses of four reference International Humic Substances Society FAs were performed. The spray solution composition was found to have a dramatic effect on the ion distributions, with high-mass aggregates (m/z approximately 2000-4000) being formed in less polar spray solutions. Positive-ion spectra for each FA obtained under optimum conditions resulted in number-average molecular weights ranging from 1700 to 1900. The mass spectra were extremely complex, with ion distributions on the order of m/z approximately 500-3000. The presence of more than one ion at each nominal mass was routinely observed. Negative-ion ESI analysis of the FA samples resulted in the observation of multiply charged ions whose distributions could be affected by the acidification of the spray solution. Solution parameters which have been reported to affect molecular weight distributions of FA such as pH, ionic strength, and concentration of multivalent cations were found to have little or no effect on the observed m/z distributions.


Assuntos
Benzopiranos/análise , Ciclotrons , Análise de Fourier , Espectrometria de Massas
9.
J Affect Disord ; 50(2-3): 97-108, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9858069

RESUMO

BACKGROUND: The study tested whether level of recovery from major depressive episodes (MDEs) predicts duration of recovery in unipolar major depressive disorder (MDD) patients. METHODS: MDD patients seeking treatment at five academic centers were followed naturalistically for 10 years or longer. Patients were divided on the basis of intake MDE recovery into residual depressive symptoms (SSD; N=82) and asymptomatic (N=155) recovery groups. They were compared on time to first episode relapse/recurrence, antidepressant medication, and comorbid mental disorders. Recovery level was also compared to prior history of recurrent MDEs ( > 4 lifetime episodes) as a predictor of relapse/recurrence. RESULTS: Residual SSD compared to asymptomatic recovery patients relapsed to their next MDE > 3 times faster (median=68 vs. 23 weeks) and to any depressive episode > 5 times faster (median=33 vs. 184 weeks). Residual SSD recovery status was significantly associated with early episode relapse (OR=3.65) and was stronger than history of recurrent MDEs (OR=1.64). Rapid relapse in the SSD group could not be attributed to higher comorbidity or lower antidepressant treatment. LIMITATIONS: Although inter-rater agreement on weekly depressive symptom ratings was very high (ICC > 0.88), some error may exist in assigning recovery levels. Antidepressant treatments were recorded, but were not controlled. CONCLUSIONS: MDE recovery is a powerful predictor of time to episode relapse/recurrence. Residual SSD recovery is associated with very rapid episode relapse which supports the idea that SSD is an active state of illness. Asymptomatic recovery is associated with prolonged delay in episode recurrence. These findings of this present study have important implications for the goals of treatment of MDD and for defining true MDE recovery.


Assuntos
Antidepressivos/uso terapêutico , Transtorno Depressivo/psicologia , Adulto , Comorbidade , Transtorno Depressivo/tratamento farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Recidiva , Índice de Gravidade de Doença , Fatores de Tempo
10.
Am J Health Syst Pharm ; 55(18): 1907-14, 1998 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-9784771

RESUMO

Hospital pharmacy staff members at a Mid-western university medical center were surveyed to determine their attitudes about the use of robots in pharmacy dispensing before a robotic system was implemented. A questionnaire seeking attitudes about the use of robots in pharmacy was distributed to 147 pharmacy staff (pharmacy managers, pharmacist practitioners, pharmacotherapists, pharmacy residents and fellows, pharmacy technicians, and salaried pharmacy students). Attitudinal items were scored on a 5-point scale ranging from very favorable to very unfavorable. The response rate was 75%. Overall, staff expressed favorable attitudes in terms of job security, professional impact, and general robotics orientation. Pharmacy managers and pharmacotherapists were the most likely to report feeling secure about their jobs; pharmacy technicians and salaried pharmacy students were slightly less positive. Favorable attitudes about the professional impact of the robotic system were demonstrated by all groups except pharmacist practitioners and pharmacy technicians. Attitudes about management issues were unfavorable; pharmacist practitioners demonstrated the least favorable attitudes. In general, responses to semantic-differential statements reflected favorable attitudes; where there were differences, pharmacy technicians showed the least positive and pharmacy managers the most positive attitudes. Respondents reported that pharmacist practitioners would be most positively affected and pharmacy technicians most negatively affected by robotic dispensing. Almost half of the respondents who provided general comments indicated that they needed more information about the use of robots. Pharmacy staff had generally favorable attitudes about the use of robots in pharmacy.


Assuntos
Atitude do Pessoal de Saúde , Sistemas de Medicação no Hospital/organização & administração , Serviço de Farmácia Hospitalar/organização & administração , Robótica , Análise de Variância , Farmacêuticos , Técnicos em Farmácia , Inquéritos e Questionários
11.
Arch Gen Psychiatry ; 55(8): 694-700, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9707379

RESUMO

BACKGROUND: Investigations of unipolar major depressive disorder (MDD) have focused primarily on major depressive episode remission/recovery and relapse/recurrence. This is the first prospective, naturalistic, long-term study of the weekly symptomatic course of MDD. METHODS: The weekly depressive symptoms of 431 patients with MDD seeking treatment at 5 academic centers were divided into 4 levels of severity: (1) depressive symptoms at the threshold for MDD; (2) depressive symptoms at the threshold for minor depressive or dysthymic disorder (MinD); (3) subsyndromal or subthreshold depressive symptoms (SSDs), below the thresholds for MinD and MDD; and (4) no depressive symptoms. The percentage of weeks at each level, number of changes in symptom level, and medication status were analyzed overall and for 3 subgroups defined by mood disorder history. RESULTS: Patients were symptomatically ill in 59% of weeks. Symptom levels changed frequently (1.8/y), and 9 of 10 patients spent weeks at 3 or 4 different levels during follow-up. The MinD (27%) and SSD (17%) symptom levels were more common than the MDD (15%) symptom level. Patients with double depression and recurrent depression had more chronic symptoms than patients with their first lifetime major depressive episode (72% and 65%, respectively, vs 46% of follow-up weeks). CONCLUSION: The long-term weekly course of unipolar MDD is dominated by prolonged symptomatic chronicity. Combined MinD and SSD level symptoms were about 3 times more common (43%) than MDD level symptoms (15%). The symptomatic course is dynamic and changeable, and MDD, MinD, and SSD symptom levels commonly alternate over time in the same patients as a symptomatic continuum of illness activity of a single clinical disease.


Assuntos
Transtorno Depressivo/diagnóstico , Adulto , Antidepressivos/uso terapêutico , Doença Crônica , Transtorno Depressivo/classificação , Transtorno Depressivo/tratamento farmacológico , Transtorno Distímico/classificação , Transtorno Distímico/diagnóstico , Transtorno Distímico/tratamento farmacológico , Feminino , Seguimentos , Humanos , Masculino , Estudos Prospectivos , Recidiva , Índice de Gravidade de Doença
13.
Plant Mol Biol ; 34(1): 15-29, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9177309

RESUMO

We have designed protein molecules based on an alpha-helical coiled-coil structure. These proteins can be tailored to complement nutritionally unbalanced seed meals. In particular, these proteins may contain up to 43% mol/mol of the essential amino acid lysine. Genes encoding such proteins were constructed using synthetic oligonucleotides and the protein stability was tested for in vivo by expression in an Escherichia coli model system. A protein containing 31% lysine and 20% methionine (CP 3-5) was expressed in transgenic tobacco seeds utilizing the seed specific bean phaseolin and soybean beta-conglycinin promoters. Both promoters provided a level of expression in the mature transgenic tobacco seeds which resulted in a significant increase in the total lysine content of the seeds. Several of these transgenic lines were analyzed for three generations to determine the stability of gene expression. Plants transformed with the soybean beta-conglycinin promoter/CP 3-5 gene consistently expressed the high-lysine phenotype through three generations. However, expression of the high-lysine phenotype in plants transformed with the bean phaseolin/CP 3-5 was variable. This is the first report of a significant increase in seed lysine content due to the seed-specific expression of a de novo protein sequence.


Assuntos
Lisina/biossíntese , Nicotiana/metabolismo , Proteínas de Plantas/biossíntese , Plantas Tóxicas , Estrutura Secundária de Proteína , Sequência de Aminoácidos , Sequência de Bases , Escherichia coli/genética , Fabaceae/genética , Vetores Genéticos , Dados de Sequência Molecular , Proteínas de Plantas/química , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Plantas Medicinais , Regiões Promotoras Genéticas , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Nicotiana/química , Nicotiana/genética , Transformação Genética
15.
Mod Healthc ; 26(41): 66, 68, 1996 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-10161914
19.
J Health Adm Educ ; 14(2): 205-37, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-10161827

RESUMO

Integrated health care systems: a concept being discussed throughout Russia and the world. A concept with three different applications and a confusing interaction with the concept of "capitation payments." The health reform debate in Russia and the NIS can only advance if greater clarity is found for these concepts, and if medical leaders are prepared for the substantial changes in provider behavior that are required with integrated health care systems fueled by capitation payments. This article explores the twin concepts of capitation and integrated health care systems, and then the leadership challenges for Russian health sector managers as they prepare for these challenges of the twenty-first century.


Assuntos
Capitação , Prestação Integrada de Cuidados de Saúde/economia , Prestação Integrada de Cuidados de Saúde/organização & administração , Reforma dos Serviços de Saúde/economia , Indicadores Básicos de Saúde , Programas de Assistência Gerenciada/economia , Programas de Assistência Gerenciada/organização & administração , Modelos Organizacionais , Planos de Incentivos Médicos , Federação Russa , Estados Unidos
20.
J Health Adm Educ ; 14(2): 239-47, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-10161828

RESUMO

In Russia, as in all countries, physicians are and will continue to be central actors in health sector reform and in health sector resource allocation decisions. How they are recognized and rewarded for their work will therefore dramatically influence the ultimate success of reforms and health sector expenditure patterns. Much of the debate in Russia and many of the articles in this special edition of the Journal are focused on creative ways to move money from purchasers to provider institutions. There has not been enough discussion nor analysis of how money needs to move within institutions to individual physicians and managers as a means to influence their behavior. A new approach to base and merit pay is needed. This article explores conceptual and practical dimensions of alternate ways to compensate physicians as clinicians and managers. New forms of recognition and types of rewards will be summarized. Managerial skills and systems needed to support such new methods will also be highlighted.


Assuntos
Planos de Incentivos Médicos , Salários e Benefícios , Atenção à Saúde/economia , Atenção à Saúde/organização & administração , Reforma dos Serviços de Saúde , Humanos , Motivação , Desenvolvimento de Programas , Federação Russa
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