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1.
Environ Manage ; 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38904707

RESUMO

Wildfires are considered a major disturbance to forest ecosystems in the Mediterranean countries of Southern Europe. Although ground-dwelling macroinvertebrates are crucial to many soil functions, there is a fundamental lack of understanding of how wildfires impact this community in the immediate term and of the role of stones in their survival. Hence, in the present study we assessed the immediate effects of wildfires in the ground-dwelling macroinvertebrate community found under stones by comparing communities in burnt and non-burnt Mediterranean oak forests. Our results revealed that stones allowed the survival of many taxa in the burnt area. However, abundance, richness, diversity, and equitability per stone were significantly lower at the burnt than unburnt sites. Furthermore, the results also showed that richness and abundance increased significantly with increasing stone depth and area, both at the burnt and unburnt sites. Significant changes at the trophic level were observed in the burnt area comparing to the unburnt, particularly a decline in predators. No significant differences were identified concerning habitat associations among taxa. Overall, this study stressed the role of stones as microhabitats and refuge for the ground-dwelling macroinvertebrate community during wildfires.

2.
Ecol Evol ; 12(9): e9337, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36188514

RESUMO

To offset the declining timber supply by shifting towards more sustainable forestry practices, industrial tree plantations are expanding in tropical production forests. The conversion of natural forests to tree plantation is generally associated with loss of biodiversity and shifts towards more generalist and disturbance tolerant communities, but effects of mixed-landuse landscapes integrating natural and plantation forests remain little understood. Using camera traps, we surveyed the medium-to-large bodied terrestrial wildlife community across two mixed-landuse forest management areas in Sarawak, Malaysia Borneo which include areas dedicated to logging of natural forests and adjacent planted Acacia forests. We analyzed data from a 25-wildlife species community using a Bayesian community occupancy model to assess species richness and species-specific occurrence responses to Acacia plantations at a broad scale, and to remote-sensed local habitat conditions within the different forest landuse types. All species were estimated to occur in both landuse types, but species-level percent area occupied and predicted average local species richness were slightly higher in the natural forest management areas compared to licensed planted forest management areas. Similarly, occupancy-based species diversity profiles and defaunation indices for both a full community and only threatened and endemic species suggested the diversity and occurrence were slightly higher in the natural forest management areas. At the local scale, forest quality was the most prominent predictor of species occurrence. These associations with forest quality varied among species but were predominantly positive. Our results highlight the ability of a mixed-landuse landscape with small-scale Acacia plantations embedded in natural forests to retain terrestrial wildlife communities while providing an alternate source of timber. Nonetheless, there was a tendency towards reduced biodiversity in planted forests, which would likely be more pronounced in plantations that are larger or embedded in a less natural matrix.

3.
Contemp Nurse ; 57(1-2): 13-27, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33794757

RESUMO

BACKGROUND: Nurses are often exposed to workplace bullying, which leads to their burnout and leaving the profession. However, the processes by which workplace bullying leads to such outcomes are not clear. AIMS: This study investigates how work-related and personal-related bullying affect nurses' occupational commitment by integrating emotional labour and emotional exhaustion. METHOD: This study employs a cross-sectional design. The model was tested using structural equation modelling with a sample of 245 Chinese nurses. RESULTS: Work-related bullying is positively related to both surface acting and deep acting, and a negative relationship exists between deep acting and emotional exhaustion. Personal-related bullying is not related to either surface acting or deep acting, but is positively related to emotional exhaustion. Emotional exhaustion is negatively related to affective occupational commitment. CONCLUSIONS: This study implies that bullying behaviours should be distinguished with work-related bullying and personal-related bullying, and emotional regulation strategies are meaningful in managing the negative impact of work-related bullying. IMPLICATION FOR NURSING MANAGEMENT: Policymakers and managers need to distinguish two types of bullying behaviour and manage them accordingly with different strategies. For nursing schools it is important to prepare nursing students with not only professional skills but also social competence and emotional management skills.


Assuntos
Bullying , Esgotamento Profissional , Recursos Humanos de Enfermagem Hospitalar , Estudos Transversais , Emoções , Humanos , Satisfação no Emprego , Inquéritos e Questionários , Local de Trabalho
4.
J Am Mosq Control Assoc ; 36(3): 175-180, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-33600587

RESUMO

A field study was carried out on the year-long residual activity of the insect growth regulator (IGR) pyriproxyfen (Nylar 0.5G) in comparison with methoprene (Altosid® XRP Pellets) against mosquito developmental stages in catch basins in northwestern Riverside County, southern California. Pyriproxyfen was applied at 75, 100, 125, 150, 175 g per catch basin and methoprene at 3.5 g per catch basin. A total of 80 catch basins (10 per each treatment and 20 for control) were used. Posttreatment observations of catch basins were carried out at weekly intervals, with all pupal collections reared to adults. Mosquito species composition in this study, consisting mostly of Culex species (693), was predominated by Cx. quinquefasciatus (92.8%), followed by Cx. erythrothorax (5.5%), Cx. tarsalis (1.2%), Cx. stigmatosoma (0.3%), and Cx. thriambus (0.2%). Activity of both IGRs was expressed as percent inhibition of adult emergence (% IAE). Data generated on % IAE showed that, like methoprene, pyriproxyfen provided complete control of mosquitoes at 75, 125, and 175 g per catch basin up to 50 wk posttreatment at the Riverside amusement park, whereas its activity against mosquitoes in catch basins treated with 100 g and 150 g at the Eastvale site was short-lived, up to 48 wk. Water samples, bioassayed against laboratory-reared, 4th-stage larvae of Cx. quinquefasciatus 1-2 wk after the 50-wk-long study, showed evidence of significant % IAE (∼50) by pyriproxyfen at the 2 higher rates (125 g, 175 g) used at the amusement park. In conclusion, pyriproxyfen can be used to effectively control mosquitoes in catch basins for 48-50 wk, depending on the rate of application.


Assuntos
Culex , Inseticidas , Metoprene , Controle de Mosquitos , Piridinas , Animais , California , Culex/crescimento & desenvolvimento , Feminino , Larva/crescimento & desenvolvimento , Masculino , Óvulo/crescimento & desenvolvimento , Pupa/crescimento & desenvolvimento
5.
J Health Organ Manag ; 31(1): 110-124, 2017 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-28260407

RESUMO

Purpose The purpose of this paper is twofold: first, to develop and test theory on how commitment human resource (HR) practices affect hospital professionals' job satisfaction that motivates them to generate desirable patient care and subsequently improve doctor-patient relationships (DPR) and second, to examine how commitment HR practices influence hospital managers and clinicians in different ways. Design/methodology/approach Using a cross-sectional survey, the authors collected data from 508 clinicians and hospital managers from 33 tertiary public hospitals in China. Structural equation model was employed to test the relationships of the variables in the study. Findings Commitment HR practices positively affect the job satisfaction of the healthcare professionals surveyed and a positive relationship is perceived between job satisfaction and DPR. Overall, the model shows a reversal on the strongest path linking job satisfaction and DPR whereby managers' main association operates through extrinsic job satisfaction while for clinicians it occurs through intrinsic satisfaction only. Practical implications DPR might be improved by applying commitment HR practices to increase healthcare professional's intrinsic and extrinsic satisfaction. In addition, while recognizing the importance of compensation and benefits to address the underpayment issue of Chinese healthcare professionals, empowerment and autonomy in work, and the use of subjects' expertise and skills may serve as stronger motivators for clinicians rather than hard economic incentives in achieving DPR improvements. Originality/value This study contributes to the small but growing body of research on human resource management (HRM) in the healthcare sector with new evidence supporting the link between commitment HR practice and work attitudes, as well as work attitudes and patient care from the perspective of clinicians and hospital managers. This study represents an initial attempt to examine the associations among commitment HR practices, job satisfaction and DPR in the Chinese healthcare sector. The findings provide evidence to support the value of commitment HR practices in Chinese hospital context, and demonstrate the importance of effective HRM in improving both hospital managers and clinicians' work attitudes.


Assuntos
Relações Médico-Paciente , Atitude do Pessoal de Saúde , China , Estudos Transversais , Administração Hospitalar , Administradores Hospitalares , Humanos , Satisfação no Emprego , Melhoria de Qualidade , Inquéritos e Questionários
6.
Epidemiol Infect ; 143(11): 2399-407, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25496703

RESUMO

We used the winter of 2009-2010, which had minimal influenza circulation due to the earlier 2009 influenza A(H1N1) pandemic, to test the accuracy of ecological trend methods used to estimate influenza-related deaths and hospitalizations. We aggregated weekly counts of person-time, all-cause deaths, and hospitalizations for pneumonia/influenza and respiratory/circulatory conditions from seven healthcare systems. We predicted the incidence of the outcomes during the winter of 2009-2010 using three different methods: a cyclic (Serfling) regression model, a cyclic regression model with viral circulation data (virological regression), and an autoregressive, integrated moving average model with viral circulation data (ARIMAX). We compared predicted non-influenza incidence with actual winter incidence. All three models generally displayed high accuracy, with prediction errors for death ranging from -5% to -2%. For hospitalizations, errors ranged from -10% to -2% for pneumonia/influenza and from -3% to 0% for respiratory/circulatory. The Serfling and virological models consistently outperformed the ARIMAX model. The three methods tested could predict incidence of non-influenza deaths and hospitalizations during a winter with negligible influenza circulation. However, meaningful mis-estimation of the burden of influenza can still result with outcomes for which the contribution of influenza is low, such as all-cause mortality.


Assuntos
Hospitalização/estatística & dados numéricos , Influenza Humana/epidemiologia , Modelos Estatísticos , Pneumonia Viral/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/mortalidade , Estudos de Coortes , Feminino , Humanos , Incidência , Vírus da Influenza A Subtipo H1N1 , Influenza Humana/mortalidade , Masculino , Pneumonia Viral/mortalidade , Doenças Respiratórias/epidemiologia , Doenças Respiratórias/mortalidade , Estações do Ano , Estados Unidos/epidemiologia
7.
Brain Behav Immun ; 31: 143-52, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23201587

RESUMO

Chronic inflammation and oxidative stress have been implicated in the pathophysiology of Major Depressive Disorder (MDD), as well as in a number of chronic medical conditions. The aim of this study was to examine the relationship between peripheral inflammatory and oxidative stress markers in un-medicated subjects with MDD compared to non-depressed healthy controls and compared to subjects with MDD after antidepressant treatment. We examined the relationships between IL-6, IL-10, and the IL-6/IL-10 inflammatory ratio vs. F2-isoprostanes (F2-IsoP), a marker of oxidative stress, in un-medicated MDD patients (n=20) before and after 8 weeks of open-label sertraline treatment (n=17), compared to healthy non-depressed controls (n=20). Among the un-medicated MDD subjects, F2-IsoP concentrations were positively correlated with IL-6 concentrations (p<0.05) and were negatively correlated with IL-10 concentrations (p<0.01). Accordingly, F2-IsoP concentrations were positively correlated with the ratio of IL-6/IL-10 (p<0.01). In contrast, in the control group, there were no significant correlations between F2-IsoPs and either cytokine or their ratio. After MDD subjects were treated with sertraline for 8 weeks, F2-IsoPs were no longer significantly correlated with IL-6, IL-10 or the IL-6/IL-10 ratio. These data suggest oxidative stress and inflammatory processes are positively associated in untreated MDD. Our findings are consistent with the hypothesis that the homeostatic buffering mechanisms regulating oxidation and inflammation in healthy individuals become dysregulated in untreated MDD, and may be improved with antidepressant treatment. These findings may help explain the increased risk of comorbid medical illnesses in MDD.


Assuntos
Antidepressivos/uso terapêutico , Transtorno Depressivo Maior/metabolismo , Inflamação/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Sertralina/uso terapêutico , Adulto , Antidepressivos/farmacologia , Transtorno Depressivo Maior/tratamento farmacológico , Feminino , Humanos , Interleucina-10/sangue , Interleucina-6/sangue , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo/fisiologia , Sertralina/farmacologia , Resultado do Tratamento
9.
Curr Med Res Opin ; 28(3): 325-34, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22292447

RESUMO

OBJECTIVE: To identify predictors of remission with placebo treatment in double-blind randomized controlled trials (RCTs) in major depressive disorder (MDD). METHOD: A total of 1017 placebo-treated patients with baseline Hamilton Depression rating scale (HAMD) total ≥15 from eight duloxetine RCTs were included. Remission was defined as endpoint (7-8 weeks) HAMD total ≤7. Data were randomly split into training data (N = 813, 80%) for model selection and test data (N = 204, 20%) for validation. Logistic regression and classification and regression tree (CART) methods were used to identify predictors of remission. Predictive accuracy of models was assessed by Receiver Operator Characteristic (ROC) curves. RESULTS: Baseline predictors for remission with placebo consistently identified with the logistic regression and CART analysis were less severe depressive symptoms (based on HAMD core symptoms), younger age, less anxiety (based on HAMD anxiety/somatization), and shorter current MDD episode duration. Associated cut-off values from the CART method characterized patient groups according to their remission likelihood. However, the predictive accuracy was modest for both methods with areas under the ROC curve of 0.6-0.65 based on test data. CONCLUSION: The derived models, although of limited value for predicting remission in individual patients, may be useful for adjusting for placebo effects in clinical trials.


Assuntos
Transtorno Depressivo Maior/tratamento farmacológico , Efeito Placebo , Adulto , Idade de Início , Antidepressivos/uso terapêutico , Transtorno Depressivo Maior/epidemiologia , Método Duplo-Cego , Cloridrato de Duloxetina , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Escalas de Graduação Psiquiátrica , Curva ROC , Ensaios Clínicos Controlados Aleatórios como Assunto , Análise de Regressão , Indução de Remissão , Tiofenos/uso terapêutico , Resultado do Tratamento
10.
Mol Psychiatry ; 17(2): 164-72, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21242992

RESUMO

Telomeres are DNA-protein complexes that cap linear DNA strands, protecting DNA from damage. When telomeres critically shorten, cells become susceptible to senescence and apoptosis. Telomerase, a cellular ribonucleoprotein enzyme, rebuilds the length of telomeres and promotes cellular viability. Leukocyte telomeres are reportedly shortened in major depression, but telomerase activity in depression has not been previously reported. Further, there are no published reports of the effects of antidepressants on telomerase activity or on the relationship between telomerase activity and antidepressant response. Peripheral blood mononuclear cell (PBMC) telomerase activity was assessed in 20 medication-free depressed individuals and 18 controls. In total, 16 of the depressed individuals were then treated with sertraline in an open-label manner for 8 weeks, and PBMC telomerase activity was reassessed in 15 of these individuals after treatment. Pre- and post-treatment symptom severity was rated with the Hamilton Depression Rating Scale. All analyses were corrected for age and sex. Pre-treatment telomerase activity was significantly elevated in the depressed individuals compared with the controls (P=0.007) and was directly correlated with depression ratings (P<0.05) across all subjects. In the depressed group, individuals with relatively lower pre-treatment telomerase activity and with relatively greater increase in telomerase activity during treatment, showed superior antidepressant responses (P<0.05 and P<0.005, respectively). This is the first report characterizing telomerase activity in depressed individuals. PBMC telomerase activity might reflect a novel aspect of depressive pathophysiology and might represent a novel biomarker of antidepressant responsiveness.


Assuntos
Transtorno Depressivo Maior/sangue , Transtorno Depressivo Maior/tratamento farmacológico , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/enzimologia , Sertralina/uso terapêutico , Telomerase/metabolismo , Adulto , Antidepressivos/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Escalas de Graduação Psiquiátrica , Estatística como Assunto
11.
Theor Appl Genet ; 122(2): 291-309, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20857082

RESUMO

Rice (Oryza sativa L.) head-rice yield (HR) is a key export and domestic quality trait whose genetic control is poorly understood. With the goal of identifying genomic regions influencing HR, quantitative-trait-locus (QTL) mapping was carried out for quality-related traits in recombinant inbred lines (RILs) derived from crosses of common parent Cypress, a high-HR US japonica cultivar, with RT0034, a low-HR indica line (129 RILs) and LaGrue, a low-HR japonica cultivar (298 RILs), grown in two US locations in 2005-2007. Early heading increased HR in the Louisiana (LA) but not the Arkansas (AR) location. Fitting QTL-mapping models to separate QTL main and QTL × environment interaction (QEI) effects and identify epistatic interactions revealed six main-effect HR QTLs in the two crosses, at four of which Cypress contributed the increasing allele. Multi-QTL models accounted for 0.36 of genetic and 0.21 of genetic × environment interaction of HR in MY1, and corresponding proportions of 0.25 and 0.37 in MY2. The greater HR advantage of Cypress in LA than in AR corresponded to a genomewide pattern of opposition of HR-increasing QTL effects by AR-specific effects, suggesting a selection strategy for improving this cultivar for AR. Treating year-location combinations as independent environments resulted in underestimation of QEI effects, evidently owing to lower variation among years within location than between location. Identification of robust HR QTLs in elite long-grain germplasm is suggested to require more detailed attention to the interaction of plant and grain development parameters with environmental conditions than has been given to date.


Assuntos
Mapeamento Cromossômico , Oryza/genética , Locos de Características Quantitativas , Arkansas , Cromossomos de Plantas , Produtos Agrícolas/genética , Endogamia , Louisiana , Oryza/crescimento & desenvolvimento , Fenótipo , Sementes/genética
12.
Epidemiol Infect ; 139(9): 1296-306, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21087538

RESUMO

In epidemiological studies of community-acquired pneumonia (CAP) that utilize administrative data, cases are typically defined by the presence of a pneumonia hospital discharge diagnosis code. However, not all such hospitalizations represent true CAP cases. We identified 3991 hospitalizations during 1997-2005 in a managed care organization, and validated them as CAP or not by reviewing medical records. To improve the accuracy of CAP identification, classification algorithms that incorporated additional administrative information associated with the hospitalization were developed using the classification and regression tree analysis. We found that a pneumonia code designated as the primary discharge diagnosis and duration of hospital stay improved the classification of CAP hospitalizations. Compared to the commonly used method that is based on the presence of a primary discharge diagnosis code of pneumonia alone, these algorithms had higher sensitivity (81-98%) and positive predictive values (82-84%) with only modest decreases in specificity (48-82%) and negative predictive values (75-90%).


Assuntos
Infecções Comunitárias Adquiridas/classificação , Infecções Comunitárias Adquiridas/epidemiologia , Pneumonia/classificação , Pneumonia/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Criança , Pré-Escolar , Infecções Comunitárias Adquiridas/diagnóstico , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Pneumonia/diagnóstico , Valor Preditivo dos Testes , Sensibilidade e Especificidade
13.
Theor Appl Genet ; 112(5): 787-96, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16463062

RESUMO

Advanced backcross quantitative trait locus (AB-QTL) analysis was used to identify QTLs for yield and yield components in a backcross population developed from a cross between hard red winter wheat (Triticum aestivum L.) variety Karl 92 and the synthetic wheat line TA 4152-4. Phenotypic data were collected for agronomic traits including heading date, plant height, kernels per spike, kernel weight, tiller number, biomass, harvest index, test weight, grain yield, protein content, and kernel hardness on 190 BC2F(2:4) lines grown in three replications in two Kansas environments. Severity of wheat soil-borne mosaic virus (WSBMV) reaction was evaluated at one location. The population was genotyped using 151 microsatellite markers. Of the ten putative QTLs identified, seven were located on homologous group 2 and group 3 chromosomes. The favorable allele was contributed by cultivated parent Karl 92 at seven QTLs including a major one for WSBMV resistance, and by the synthetic parent at three QTLs: for grain hardness, kernels per spike, and tiller number.


Assuntos
Endogamia , Locos de Características Quantitativas , Triticum/genética , Mapeamento Cromossômico , Cromossomos de Plantas , Ligação Genética , Genótipo , Repetições de Microssatélites , Fenótipo , Triticum/anatomia & histologia , Triticum/fisiologia
14.
J Clin Endocrinol Metab ; 88(12): 5710-6, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14671157

RESUMO

To investigate the effects of nonsteroidal antiinflammatory drugs (NSAIDs) on thyroid tests, 25 healthy subjects underwent a single-dose study and/or a 1-wk study. In the single-dose study, subjects received a single dose of one of six NSAIDs (aspirin, salsalate, meclofenamate, ibuprofen, naproxen, or indomethacin) at 0800 h. Total and free thyroid hormones and TSH were analyzed 0, 1, 2, 3, 4, and 8 h later. In the 1-wk study, subjects received one of six NSAIDs for 7 d. Thyroid hormones and TSH were analyzed at 0800 h each day. Total T(4) and total T(3) were measured by RIA, free T(4) and free T(3) were measured by equilibrium dialysis, and TSH was measured by immunometric assay. There were no changes in any hormones after a single dose or 1 wk of ibuprofen, naproxen, or indomethacin. Single-dose aspirin or salsalate decreased, whereas meclofenamate increased, various total and free thyroid hormone measurements. One week of aspirin or salsalate decreased total T(4), free T(4) (salsalate only), total T(3), free T(3), and TSH. These data confirm that aspirin, salsalate, and meclofenamate affect total and free thyroid hormone measurements and identify three NSAIDs that did not change thyroid tests. TSH remained within the normal range during acute or 1-wk administration of all of the NSAIDs.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Tiroxina/sangue , Tri-Iodotironina/sangue , Adulto , Anti-Inflamatórios não Esteroides/administração & dosagem , Esquema de Medicação , Feminino , Humanos , Masculino , Radioimunoensaio , Testes de Função Tireóidea
15.
Theor Appl Genet ; 106(2): 287-92, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12596729

RESUMO

A set of 130 wheat recombinant inbred lines (RILs) developed from a cross between parents susceptible (WL711) and resistant (HD29) to Karnal bunt (caused by Tilletia indica), were screened for 3 years with the pathogen populations prevalent in northern India. When 90 simple sequence repeats (SSRs) and 81 amplified fragment length polymorphism (AFLP) loci were mapped on the RILs, markers on chromosomes 2A, 4B and 7B accounted collectively for about one-third of the variation in the disease reaction. The genomic region of largest effect, identified on the long arm of chromosome 4B, reduced Karnal bunt disease by half in three different experiments and accounted for up to 25% of the phenotypic variation for KB reaction. A closely linked SSR marker, GWM538, may be useful in marker-assisted selection for Karnal bunt resistance in wheat.


Assuntos
Mapeamento Cromossômico , Genes de Plantas/genética , Doenças das Plantas/genética , Triticum/genética , Cruzamentos Genéticos , Marcadores Genéticos , Variação Genética , Genoma de Planta , Repetições de Microssatélites , Fenótipo , Polimorfismo de Fragmento de Restrição , Locos de Características Quantitativas , Característica Quantitativa Herdável , Técnica de Amplificação ao Acaso de DNA Polimórfico , Recombinação Genética
16.
Philos Trans R Soc Lond B Biol Sci ; 357(1428): 1793-808, 2002 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-12626013

RESUMO

The principal target of lateral geniculate nucleus in the cat visual cortex is the stellate neurons of layer 4. In previously reported work with intracellular recording and extracellular stimulation in slices of visual cortex, three general classes of fast excitatory synaptic potentials (EPSPs) in layer 4a spiny stellate neurons were identified. One of these classes, characterized by large and relatively invariant amplitudes (mean 1.7 mV, average coefficient of variation (CV) 0.083) were attributed to the action of geniculate axons because, unlike the other two classes, they could not be matched by intracortical inputs, using paired recording. We have examined in detail the properties of this synaptic input in twelve examples, selecting for study those EPSPs where there was secure extracellular stimulation of the single fibre input to a pair of stimuli 50 ms apart. In our analysis, we conclude that the depression that these inputs show to the second stimulus is entirely postsynaptic, since the evidence strongly suggests that the probability of transmitter release at the synaptic site(s) remains 1.0 for both stimuli. We argue that the most plausible explanation for this postsynaptic depression is a reduction in the average probability of opening the synaptic channels. Using a simple biochemical analysis (c.f. Sigworth plot), it is then possible to calculate the number of synaptic channels and their probability of opening, for each of the 12 connections. The EPSPs had a mean amplitude of 1.91 mV (+/- 1.3 mV SD) and a mean CV of 0.067 (+/- 0.022). The calculated number of channels ranged from 20 to 158 (59.4 +/- 48.7) and their probability of opening to the first EPSP had an average of 0.83 (+/- 0.09), with an average depression of the probability to 0.60 for the second EPSP. Geniculate afferents also terminate in layer 6. Intracellular recordings were also made in the upper part of this layer and a total of 51 EPSPs were recorded from pyramidal cells of three principal types. Amongst this dataset we sought EPSPs with similar properties to those characterized in layer 4a. Three examples were found, which is a much lower percentage (6%) than the incidence of putative geniculate EPSPs found in layer 4a (42%).


Assuntos
Córtex Visual/anatomia & histologia , Córtex Visual/fisiologia , Potenciais de Ação , Animais , Gatos , Potenciais Pós-Sinápticos Excitadores , Corpos Geniculados/citologia , Corpos Geniculados/fisiologia , Técnicas In Vitro , Potenciais da Membrana , Modelos Neurológicos , Vias Neurais/citologia , Vias Neurais/fisiologia , Neurônios/fisiologia , Células Piramidais/fisiologia , Receptores de AMPA/fisiologia , Córtex Visual/citologia
17.
J Clin Psychiatry ; 62 Suppl 24: 18-22, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11676429

RESUMO

As the population of people over 65 years of age increases, clinicians will see more cases of late-life depression. Currently, the rates of depression in the elderly are higher for nursing home patients and other medical inpatients and outpatients than for the noninstitutionalized, non-medically ill elderly. Depression in the elderly may be difficult to diagnose because of factors such as late onset, comorbid medical illness, dementia, and bereavement, but depression is not a natural part of aging. People who are depressed have increased suffering, impaired functioning, and increased mortality. Fortunately, antidepressants have been shown to effectively treat late-life depression. While monoamine oxidase inhibitors (MAOIs) and tricyclic antidepressants (TCAs) are efficacious for treating depression in the elderly, their side effect profiles may be difficult and even dangerous for some older patients. However, serotonin selective reuptake inhibitors (SSRIs) and other second generation antidepressants appear to be both effective and better tolerated in the elderly. Since elderly patients may be more sensitive to drugs, clinicians may need to closely monitor these patients for dosing, side effects, and drug-drug interactions.


Assuntos
Transtorno Depressivo/diagnóstico , Transtorno Depressivo/tratamento farmacológico , Fatores Etários , Idade de Início , Idoso , Antidepressivos/uso terapêutico , Antidepressivos de Segunda Geração/uso terapêutico , Cognição/efeitos dos fármacos , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inibidores da Monoaminoxidase/uso terapêutico , Nortriptilina/farmacologia , Nortriptilina/uso terapêutico , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Sertralina/farmacologia , Sertralina/uso terapêutico , Resultado do Tratamento
18.
Am J Cardiol ; 88(2): 118-23, 2001 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-11448406

RESUMO

T-axis shift has been reported to be an indicator of increased mortality risk. We evaluated the association of spatial T-axis deviation with incident coronary heart disease (CHD) events in older men and women free from clinically overt CHD. Spatial T-axis deviation was measured from the standard 12-lead electrocardiogram of a subgroup of 4,173 subjects considered free of CHD at baseline in the Cardiovascular Health Study, a prospective cohort study of risk factors for CHD and stroke in older men and women. Cox regression analysis was used to evaluate the association of altered repolarization with the risk of incident CHD events. The prevalence of marked T-axis deviation (> or =45 degrees ) was 12%. During the median follow-up of 7.4 years, there were 161 CHD deaths, 743 deaths from all causes, and 679 incident CHD events. Adjusting for demographic and clinical risk factors, including other electrocardiographic abnormalities, there was a nearly twofold excess risk of CHD death, and approximately a 50% excess risk of incident CHD and all-cause mortality for those with marked T-axis deviation. From other electrocardiographic abnormalities, only QT prolongation was associated with excess risk for incident CHD comparable to that for abnormal T-axis deviation. These results suggest that T-axis deviation is an easily quantified marker for subclinical disease and an independent indicator for the risk of incident CHD events in older men and women free of CHD.


Assuntos
Doença das Coronárias/epidemiologia , Eletrocardiografia , Idoso , Algoritmos , Estudos de Coortes , Doença das Coronárias/diagnóstico , Feminino , Seguimentos , Humanos , Masculino , Prevalência , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Análise de Sobrevida
19.
J Public Health Manag Pract ; 7(4): 96-104, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11434048

RESUMO

In an effort to continually improve performance of the essential public health services with community partners, the diverse public health workforce in a major metropolitan area engaged in an organizational learning process. Core public health organizational competencies, identified in a multi-year collaborative applied research initiative, provided the curricula content for the public health learning experience. All members (about 600) of the Columbus and Franklin County (Ohio) Health Departments participated in four one-half day small group, highly interactive modules conducted during a 2-year period. The purpose of this article is to describe the design and implementation of this workforce intervention, the lessons learned, and implications for developing organizational capacity and improved performance.


Assuntos
Eficiência Organizacional , Administração em Saúde Pública/normas , Saúde Pública/educação , Desenvolvimento de Pessoal/organização & administração , Gestão da Qualidade Total/organização & administração , Educação Baseada em Competências , Educação Continuada/organização & administração , Humanos , Liderança , Aprendizagem , Ohio , Poder Psicológico , Competência Profissional , Avaliação de Programas e Projetos de Saúde , Prática de Saúde Pública/normas , Recursos Humanos
20.
Cardiol Young ; 11(3): 295-300, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11388624

RESUMO

OBJECTIVE: Thyroid hormone has important effects on cardiovascular performance. This study was performed to evaluate the changes in levels of triiodothyronine following the first stage of reconstruction for hypoplastic left heart syndrome. METHODS: We enrolled 14 newborns with hypoplastic left heart syndrome scheduled for first stage reconstruction. Blood samples were obtained pre-, intra-, and post-operatively. Levels of free and total triiodothyronine were determined by radioimmunoassay. Statistical comparison was performed using Wilcoxon's signed rank test. RESULTS: The levels of free triiodothyronine decreased from a baseline of 355+/-31 pg/dl to 205+/-21 pg/dl upon the institution of bypass, and declined to a level of 135+/-9 pg/dl at 24 hours postoperatively. Similarly, levels of total triiodothyronine decreased from 101+/-15 ng/dl to 65+/-4 ng/dl upon the institution of bypass, and continued to decline during the first 24 hours postoperatively. Levels of free and total triiodothyronine had returned to baseline by the fifth postoperative day. CONCLUSIONS: The data demonstrate significant decreases in levels of free and total triiodothyronine during the early postoperative period. These changes in levels of thyroid hormone may have adverse effects on cardiac function during this phase of recovery.


Assuntos
Síndrome do Coração Esquerdo Hipoplásico/sangue , Síndrome do Coração Esquerdo Hipoplásico/cirurgia , Procedimentos de Cirurgia Plástica , Tri-Iodotironina/análise , Adulto , Ponte Cardiopulmonar , Feminino , Seguimentos , Humanos , Lactente , Bem-Estar do Lactente , Tempo de Internação , Masculino , Radioimunoensaio/métodos , Tri-Iodotironina/sangue
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