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1.
Epidemiol Infect ; 145(1): 23-29, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27677229

RESUMO

Over 300 cases of acute toxoplasmosis are confirmed by reference testing in England and Wales annually. We conducted a case-control study to identify risk factors for Toxoplasma gondii infection to inform prevention strategies. Twenty-eight cases and 27 seronegative controls participated. We compared their food history and environmental exposures using logistic regression to calculate odds ratios (OR) and 95% confidence intervals in a model controlling for age and sex. Univariable analysis showed that the odds of eating beef (OR 10·7, P < 0·001), poultry (OR 6·4, P = 0·01) or lamb/mutton (OR 4·9, P = 0·01) was higher for cases than controls. After adjustment for potential confounders a strong association between beef and infection remained (OR 5·6, P = 0·01). The small sample size was a significant limitation and larger studies are needed to fully investigate potential risk factors. The study findings emphasize the need to ensure food is thoroughly cooked and handled hygienically, especially for those in vulnerable groups.


Assuntos
Toxoplasma/isolamento & purificação , Toxoplasmose/epidemiologia , Adulto , Estudos de Casos e Controles , Inglaterra/epidemiologia , Comportamento Alimentar , Feminino , Doenças Transmitidas por Alimentos/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Inquéritos e Questionários , País de Gales/epidemiologia
2.
J Fish Biol ; 88(4): 1321-34, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26840014

RESUMO

This study explores how muscle and liver energy stores are linked with social status and the social environment in Neolamprologus pulcher, a cooperatively breeding fish that lives in colonies comprised of up to 200 distinct social groups. Subordinate muscle energy stores were positively correlated with the number of neighbouring social groups in the colony, but this pattern was not observed in dominant N. pulcher. Furthermore, liver energy stores were smaller in dominants living at the edge of the colony compared with those living in the colony centre, with no differences among subordinates in liver energy stores. Subordinate N. pulcher may build up large energy stores in the muscles to fuel rapid growth after dispersal, which could occur more frequently in high-density environments. Dominant N. pulcher may use the more easily mobilized energy stores in the liver to fuel daily activities, which could be more energetically demanding on the edge of the colony as a result of the increased predation defence needed on the edge. Overall, this study demonstrates that both subordinate and dominant physiology in N. pulcher varies with characteristics of the social environment. Furthermore, dominant and subordinate energy storage strategies appear to differ due to status-dependent variation in daily activities and variation in the need to prepare for future reproductive or dispersal opportunities.


Assuntos
Ciclídeos/fisiologia , Metabolismo Energético/fisiologia , Músculos/metabolismo , Predomínio Social , Meio Social , Animais , Feminino , Modelos Lineares , Fígado/metabolismo , Masculino , Tamanho do Órgão , Comportamento Predatório , Reprodução/fisiologia
3.
J Therm Biol ; 47: 63-74, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25526656

RESUMO

Anthropogenic climate change is altering temperature regimes for coastal marine fishes. However, given that temperature changes will not occur in isolation of other stressors, it is necessary to explore the potential consequences of stress on the thermal tolerances and preferences of tropical marine fish in order to understand the thresholds for survival, and predict the associated coastal ecological consequences. In this study, we used exogenous cortisol injections to investigate the effects of a thermal challenge on checkered puffers (Sphoeroides testudineus) as a secondary stressor. There were no significant differences between control and cortisol-treated fish 48h following cortisol treatment for swimming ability (using a chase to exhaustion protocol), blood glucose concentrations or standard metabolic rate. In the lab, control and cortisol-treated puffers were exposed to ambient (29.1±1.5°C), ambient +5°C (heat shock) and ambient -5°C (cold shock) for 4h and to evaluate the consequences of abrupt temperature change on puff performance and blood physiology. Following cold shock, control fish exhibited increases in cortisol levels and weak 'puff' performance. Conversely, fish dosed with cortisol exhibited consistently high cortisol levels independent of thermal treatment, although there was a trend for an attenuated cortisol response in the cortisol-treated fish to the cold shock treatment. A 20-day complementary field study conducted in the puffer's natural habitat, a tidal creek in Eleuthera, The Bahamas, revealed that cortisol-injected fish selected significantly cooler temperatures, measured using accumulated thermal units, when compared to controls. These results, and particularly the discrepancies between consequences documented in the laboratory and the ecological trends observed in the field, highlight the need to establish the link between laboratory and field data to successfully develop management policies and conservation initiatives with regards to anthropogenic climate change.


Assuntos
Resposta ao Choque Frio/efeitos dos fármacos , Resposta ao Choque Térmico/efeitos dos fármacos , Hidrocortisona/farmacologia , Tetraodontiformes/fisiologia , Animais , Bahamas , Glicemia , Natação , Temperatura , Tetraodontiformes/metabolismo
4.
N Engl J Med ; 365(1): 32-43, 2011 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-21732835

RESUMO

BACKGROUND: Nesiritide is approved in the United States for early relief of dyspnea in patients with acute heart failure. Previous meta-analyses have raised questions regarding renal toxicity and the mortality associated with this agent. METHODS: We randomly assigned 7141 patients who were hospitalized with acute heart failure to receive either nesiritide or placebo for 24 to 168 hours in addition to standard care. Coprimary end points were the change in dyspnea at 6 and 24 hours, as measured on a 7-point Likert scale, and the composite end point of rehospitalization for heart failure or death within 30 days. RESULTS: Patients randomly assigned to nesiritide, as compared with those assigned to placebo, more frequently reported markedly or moderately improved dyspnea at 6 hours (44.5% vs. 42.1%, P=0.03) and 24 hours (68.2% vs. 66.1%, P=0.007), but the prespecified level for significance (P≤0.005 for both assessments or P≤0.0025 for either) was not met. The rate of rehospitalization for heart failure or death from any cause within 30 days was 9.4% in the nesiritide group versus 10.1% in the placebo group (absolute difference, -0.7 percentage points; 95% confidence interval [CI], -2.1 to 0.7; P=0.31). There were no significant differences in rates of death from any cause at 30 days (3.6% with nesiritide vs. 4.0% with placebo; absolute difference, -0.4 percentage points; 95% CI, -1.3 to 0.5) or rates of worsening renal function, defined by more than a 25% decrease in the estimated glomerular filtration rate (31.4% vs. 29.5%; odds ratio, 1.09; 95% CI, 0.98 to 1.21; P=0.11). CONCLUSIONS: Nesiritide was not associated with an increase or a decrease in the rate of death and rehospitalization and had a small, nonsignificant effect on dyspnea when used in combination with other therapies. It was not associated with a worsening of renal function, but it was associated with an increase in rates of hypotension. On the basis of these results, nesiritide cannot be recommended for routine use in the broad population of patients with acute heart failure. (Funded by Scios; ClinicalTrials.gov number, NCT00475852.).


Assuntos
Dispneia/tratamento farmacológico , Insuficiência Cardíaca/tratamento farmacológico , Natriuréticos/uso terapêutico , Peptídeo Natriurético Encefálico/uso terapêutico , Readmissão do Paciente/estatística & dados numéricos , Doença Aguda , Idoso , Método Duplo-Cego , Dispneia/etiologia , Feminino , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/mortalidade , Humanos , Hipotensão/induzido quimicamente , Análise de Intenção de Tratamento , Nefropatias/etiologia , Masculino , Pessoa de Meia-Idade , Natriuréticos/efeitos adversos , Peptídeo Natriurético Encefálico/efeitos adversos , Recidiva
5.
Int Psychogeriatr ; 26(5): 857-69, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24507481

RESUMO

BACKGROUND: Behavioral and psychological symptoms of dementia (BPSD) are often considered to be the greatest challenge in dementia care, leading to increased healthcare costs, caregiver burden, and placement into care facilities. With potential for pharmacological intervention to exacerbate behaviors or even lead to mortality, the development and rigorous testing of non-pharmacological interventions is vital. A pilot of the Tailored Activities Program (TAP) for reducing problem behaviors in people with dementia was conducted in the United States with promising results. This randomized trial will investigate the effectiveness of TAP for reducing the burden of BPSD on persons with dementia and family caregivers within an Australian population. This trial will also examine the cost-effectiveness and willingness to pay for TAP compared with a control group. METHODS: This randomized trial aims to recruit 180 participant dyads of a person with dementia and their caregivers. Participants will have a diagnosis of dementia, exhibit behaviors as scored by the Neuropsychiatric Inventory, and the caregiver must have at least 7 h per week contact. Participants will be randomly allocated to intervention (TAP) or control (phone-based education sessions) groups, both provided by a trained occupational therapist. Primary outcome measure will be the revised Neuropsychiatric Inventory - Clinician rating scale (NPI-C) to measure BPSD exhibited by the person with dementia. CONCLUSIONS: This trial investigates the effectiveness and cost-effectiveness of TAP within an Australian population. Results will address a significant gap in the current Australian community-support base for people living with dementia and their caregivers.


Assuntos
Atividades Cotidianas/psicologia , Sintomas Comportamentais , Efeitos Psicossociais da Doença , Demência , Competência Mental/psicologia , Terapia Ocupacional/métodos , Qualidade de Vida/psicologia , Idoso , Austrália , Sintomas Comportamentais/diagnóstico , Sintomas Comportamentais/etiologia , Sintomas Comportamentais/terapia , Cuidadores/educação , Cuidadores/psicologia , Informação de Saúde ao Consumidor/métodos , Análise Custo-Benefício , Demência/complicações , Demência/diagnóstico , Demência/economia , Demência/psicologia , Demência/terapia , Feminino , Humanos , Masculino , Avaliação das Necessidades , Testes Neuropsicológicos , Avaliação de Resultados em Cuidados de Saúde
6.
Artigo em Inglês | MEDLINE | ID: mdl-22179071

RESUMO

The glucocorticoid (GC) stress response is thought to be an individual trait associated with behaviour and life history strategies. Studies exploring such relationships typically assume measured hormone values to be repeatable within an individual. However, repeatability of GCs has proven variable in wild animals and underlying reasons remain unknown. We assessed individual repeatability of circulating stress-induced cortisol, the primary GC in teleost fish, and glucose concentrations in a wild teleost fish held under consistent laboratory conditions. We also tested the hypothesis that the magnitude of intra-individual variability in stress-induced cortisol concentrations ("cortisol variability") is influenced by body condition. Wild-caught bluegill sunfish (Lepomis macrochirus) were subjected to repeated standardized stressors and blood sampled (3 times over 6 days) once cortisol concentrations peaked. Various indicators of fish condition, both whole body and physiological, were also measured. Overall, stress-induced circulating cortisol concentrations were repeatable but stress-induced glucose was not. Cortisol variability was related to Fulton's condition factor and size (eviscerated mass) where smaller fish in poor condition exhibited increased cortisol variability. The findings have implications for the interpretation of studies that examine correlates of GC concentrations as they suggest consistency in stress responsiveness is influenced by factors such as size and condition.


Assuntos
Hidrocortisona/sangue , Perciformes/fisiologia , Animais , Glicemia , Proteínas Sanguíneas/metabolismo , Peso Corporal , Feminino , Hematócrito , Masculino , Perciformes/sangue , Reprodutibilidade dos Testes , Fatores Sexuais , Estresse Fisiológico
7.
Artigo em Inglês | MEDLINE | ID: mdl-21971873

RESUMO

Patterns of glucocorticoid (GC) hormone regulation exhibit considerable inter-individual variation that is often examined relative to individual traits and fitness measures. Although stress-induced GC concentrations are repeatable within an individual in captive populations, this assumption remains untested in wild animals in their natural environment across longer time periods. We assessed the repeatability of baseline and post-stress GC concentrations in a wild teleost fish. Largemouth bass (Micropterus salmoides) were captured and subjected to a standard stress protocol and then stocked into a small research lake. Upon recapture by angling up to 1 year later (n = 26), fish were re-sampled following identical methods. After controlling for a strong effect of water temperature, we confirmed repeatability of post-stress cortisol concentrations despite stress presumed to accompany relocation. We documented no consistency in baseline GC concentrations. This study serves as an important validation for the use of post-stress cortisol concentrations as an individual trait. However, the effect size of repeatability was lower than that found in other taxa. Results also bring forth the reality that environmental variables such as temperature must be considered in studies where these factors can vary, such as when sampling wild animals at liberty.


Assuntos
Envelhecimento/metabolismo , Bass/sangue , Hidrocortisona/sangue , Estresse Fisiológico , Estresse Psicológico/sangue , Fatores Etários , Animais , Biomarcadores/sangue , Reprodutibilidade dos Testes , Temperatura
8.
Br J Sports Med ; 43(4): 288-92, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18948352

RESUMO

OBJECTIVE: The aim of this study was to investigate the kinetics, kinematics and muscle activity in runners with Achilles tendinopathy. DESIGN: Case-control study. SETTING: Biomechanics laboratory. PARTICIPANTS: 21 runners free from injury and 21 runners with Achilles tendinopathy performed 10 running trials with standardised running shoes. Injured runners were diagnosed clinically according to established diagnostic criteria. Uninjured runners had been injury-free for at least 2 years. MAIN OUTCOME MEASUREMENTS: During each trial, kinetic and lower limb kinematic data were measured using a strain gauge force plate and six infrared cameras respectively. Electromyographic (EMG) data from six muscles (tibialis anterior (TA), peroneus longus (PE), lateral gastrocnemius (LG), rectus femoris (RF), biceps femoris (BF) and gluteus medius (GM)) were measured with a telemetric EMG system. RESULTS: Knee range of motion (heel strike to midstance) was significantly lower in injured runners than in uninjured runners. Similarly, preactivation (integrated EMG (IEMG) in 100 ms before heel strike) of TA was lower for injured runners than uninjured runners. RF and GM IEMG activity 100 ms after heel strike was also lower in the injured group. However, impact forces were not different between the two groups. CONCLUSION: Altered knee kinematics and reduced muscle activity are associated with Achilles tendinopathy in runners. Rehabilitation exercises or other mechanisms (e.g. footwear) that affect kinematics and muscle activity may therefore be beneficial in the treatment of runners with Achilles tendinopathy.


Assuntos
Tendão do Calcâneo/fisiopatologia , Músculo Esquelético/fisiopatologia , Corrida/fisiologia , Tendinopatia/fisiopatologia , Tendão do Calcâneo/lesões , Adulto , Fenômenos Biomecânicos/fisiologia , Estudos de Casos e Controles , Eletromiografia , Terapia por Exercício/métodos , Feminino , Humanos , Articulação do Joelho/fisiopatologia , Masculino , Amplitude de Movimento Articular/fisiologia , Corrida/lesões , Tendinopatia/reabilitação
9.
Eur Respir J ; 32(4): 931-7, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18614560

RESUMO

The genetic factors that contribute to the development of chronic obstructive pulmonary disease (COPD) are poorly understood. Many candidate genes have been proposed, including enzymes that protect the lung against oxidative stress, such as microsomal epoxide hydrolase (EPHX1) and glutamate-cysteine ligase (GCL). To date, most reported findings have been for EPHX1, particularly in relation to functional variants associated with fast and slow metabolism of epoxide intermediates. The present study aimed to identify any association of variation in these genes with COPD susceptibility or severity. In total, 1,017 white COPD patients and 912 nondiseased age and sex matched smoking controls were genotyped for six single nucleotide polymorphisms (SNPs) in EPHX1 (including the fast and slow variants and associated haplotypes), and eight SNPs in the two genes encoding GCL. GCL is a rate-limiting enzyme in the synthesis of glutathione, a major contributor to anti-oxidant protection in the lung. No association of variation was found in EPHX1 or GCL with susceptibility to COPD or disease severity. This is the largest reported study to date and is well powered to detect associations that have been previously suggested. The current data indicate that these genetic variants are unlikely to be related to susceptibility or disease severity in white chronic obstructive pulmonary disease patients.


Assuntos
Epóxido Hidrolases/genética , Glutamato-Cisteína Ligase/genética , Doença Pulmonar Obstrutiva Crônica/genética , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Variação Genética , Genótipo , Glutationa/metabolismo , Haplótipos , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Fumar
10.
Curr Top Microbiol Immunol ; 312: 43-69, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17089793

RESUMO

Rhesus monkey rhadinovirus (RRV) is one of the closest phylogenetic relatives to the human pathogen Kaposi sarcoma-associated herpesvirus (KSHV)-a gamma-2 herpesvirus and the etiologic agent of three malignancies associated with immunosuppression. In contrast to KSHV, RRV displays robust lytic-phase growth in culture, replicating to high titer, and therefore holds promise as an effective model for studying primate gammaherpesvirus lytic gene transcription as well as virion structure, assembly, and proteomics. More recently, investigators have devised complementary latent systems of RRV infection, thereby also enabling the characterization of the more restricted latent transcriptional program. Another benefit of working with RRV as a primate gammaherpesvirus model is that its efficient lytic growth makes genetic manipulation easier than that in its human counterpart. Exploiting this quality, laboratories have already begun to generate mutant RRV, setting the stage for future work investigating the function of individual viral genes. Finally, rhesus macaques support experimental infection with RRV, providing a natural in vivo model of infection, while similar nonhuman systems have remained resistant to prolonged KSHV infection. Recently, dual infection with RRV and a strain of simian immunodeficiency virus (SIV) has led to a lymphoproliferative disorder (LPD) reminiscent of multicentric Castleman disease (MCD)--a clinical manifestation of KSHV infection in a subset of immunosuppressed patients. RRV, in short, shows a high degree of homology with KSHV yet is more amenable to experimental manipulation both in vitro and in vivo. Taken together, these qualities ensure its current position as one of the most relevant viral models of KSHV biology and infection.


Assuntos
Herpesvirus Humano 8/genética , Macaca mulatta/virologia , Rhadinovirus/genética , Animais , Capsídeo/química , Genoma Viral , Herpesvirus Humano 8/química , Herpesvirus Humano 8/fisiologia , Rhadinovirus/química , Rhadinovirus/fisiologia , Transcrição Gênica , Vírion/ultraestrutura
12.
Mol Cell Biol ; 1(4): 303-9, 1981 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-6152854

RESUMO

Polyadenylated ribonucleic acid (RNA) was isolated from chicken skeletal and smooth muscle and translated in a cell-free rabbit reticulocyte system. Both types of muscle tissue contain messenger RNAs that code for the intermediate filament proteins desmin and vimentin, and the relative concentrations of the two translation products reflect the prevalence of the two proteins in vivo. Desmin synthesis represents a greater proportion of the total protein synthesis from smooth muscle RNA than from skeletal muscle RNA, whereas the converse is true of vimentin synthesis. Fractionation of the RNA on formamide-containing sucrose gradients before translation indicates that the desmin messenger RNA is larger than the vimentin messenger RNA and contains an extensive noncoding segment. The desmin and vimentin messages code predominantly for the non-phosphorylated forms of desmin and vimentin. However, the ratio of phosphorylated to unphosphorylated forms of the proteins could be increased by adding cyclic adenosine monophosphate-dependent kinase activity to the translation mixtures. These results suggest that desmin and vimentin are each synthesized from a single messenger RNA species and that posttranslational phosphorylation generates the additional isoelectric variants of each which are observed in vivo.


Assuntos
Desmina/biossíntese , Biossíntese de Proteínas , Vimentina/biossíntese , Animais , Galinhas , Desmina/genética , Técnicas In Vitro , Músculos/metabolismo , Fosforilação , Poli A/genética , Processamento de Proteína Pós-Traducional , RNA Mensageiro/genética , Vimentina/genética
13.
J Hazard Mater ; 140(1-2): 389-98, 2007 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-17126484

RESUMO

Aerosol samples of PM(10) were collected during summer and winter 2003 at two different sites in the Messogia Basin northeast of Athens, to demonstrate the variations of heavy metals in PM(10) and examine their relationship with both gaseous pollutants and meteorological parameters. Estimated heavy metals during the experimental campaign were mercury (Hg), cadmium (Cd), lead (Pb), nickel (Ni) and arsenic (As). The average heavy metal concentrations for the first site (Spata) constituted 0.66-14.7ng/m(3) for the summer period and 0.14-19.5ng/m(3) for the winter period. At the second site (Koropi), the corresponding values varied between 0.89 and 13.3ng/m(3) and 0.16 and 24.7ng/m(3), respectively. PM(10) Hg, PM(10) Cd and PM(10) Ni contents showed regular daily variations, with higher mass percentages during the summer, indicating differences in local PM(10) sources for each season. On the contrary, PM(10) Pb presented higher mass percentages during the winter. Examination of the relationship between heavy metals and meteorological parameters indicated a higher correlation with temperature and relative humidity, especially for Pb. In addition, most of the heavy metals (apart from Hg) presented an expected correlation with nitrate oxides (NO(x)), PM(10) and ozone (O(3)). Higher correlations with both meteorological parameters and gaseous pollutants were observed during the winter experimental campaign. Maximum heavy metal concentrations at both sites were observed during days with NE or NNE prevailing winds during the summer campaign, while the winter period was characterized with maximums during days with W or WNW prevailing winds.


Assuntos
Aerossóis/química , Poluentes Atmosféricos/análise , Arsênio/análise , Metais Pesados/análise , Monitoramento Ambiental , Grécia , Estações do Ano
14.
Biochim Biophys Acta ; 658(2): 387-96, 1981 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-6166323

RESUMO

Four alpha-amylase (1,4-alpha-D-glucan glucanohydrolase, EC 3.2.1.1) inhibitors were isolated from an albumin fraction of wheat flour by ion-exchange and gel-filtration chromatography. The purified inhibitors were characterized according to their electrophoretic mobilities, molecular weights, carbohydrate, content, sulphydryl content, susceptibility to proteolytic digestion and specificities in inhibiting human salivary and pancreatic alpha-amylases. The properties of these inhibitors ae compared to similar proteins isolated by other workers.


Assuntos
Amilases/antagonistas & inibidores , Pâncreas/enzimologia , Glândulas Salivares/enzimologia , alfa-Amilases/antagonistas & inibidores , Fenômenos Químicos , Química , Inibidores Enzimáticos/isolamento & purificação , Temperatura Alta , Humanos , Técnicas In Vitro , Peso Molecular , Peptídeo Hidrolases , Triticum
15.
Biochim Biophys Acta ; 658(2): 397-405, 1981 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-6166324

RESUMO

The interaction of four purified alpha-amylase (1,4-alpha-D-glucan glucanohydrolase, EC 3.2.1.1) inhibitors with human salivary and pancreatic alpha-amylases was investigated. The inhibitory activity of the four proteins towards salivary alpha-amylase was significantly increased by pre-incubation of the enzyme with inhibitor before adding substrate. This effect was not observed with the inhibition of pancreatic alpha-amylase by inhibitors 1 and 2. Inhibition of both amylases was affected to different degrees by incubating starch with inhibitor prior to the addition of enzyme. Maltose, at concentrations which only slightly affected amylase activity, prevented the inhibition of both enzymes by all four inhibitors. Gel filtration studies on salivary amylase-inhibitor mixtures showed the formation of EI complexes on a mol-to-mol ratio. A similar complex between pancreatic alpha-amylase and inhibitor 4 was observed, though complex formation between pancreatic alpha-amylase and the other inhibitors was not clearly demonstrated.


Assuntos
Amilases/antagonistas & inibidores , Isoenzimas/antagonistas & inibidores , alfa-Amilases/antagonistas & inibidores , Sítios de Ligação , Inibidores Enzimáticos/metabolismo , Humanos , Técnicas In Vitro , Maltose/farmacologia , Pâncreas/enzimologia , Glândulas Salivares/enzimologia , Amido/metabolismo , Triticum
16.
Circulation ; 99(14): 1816-21, 1999 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-10199877

RESUMO

BACKGROUND: Previous natural history studies in broad populations of heart failure patients have associated female gender with improved survival, particularly in patients with a nonischemic etiology of ventricular dysfunction. This study investigates whether a similar survival advantage for women would be evident among patients with advanced heart failure. METHODS AND RESULTS: The study analysis is based on the Flolan International Randomized Survival Trial (FIRST) study which enrolled 471 patients (359 men and 112 women) who had evidence of end-stage heart failure with marked symptoms (60% NYHA class IV) and severe left ventricular dysfunction (left ventricular ejection fraction 18+/-4.9%). A Cox proportional-hazards model, adjusted for age, gender, 6-minute walk, dobutamine use at randomization, mean pulmonary artery blood pressure, and treatment assignment, showed a significant association between female gender and better survival (relative risk of death for men versus women was 2.18, 95% CI 1.39 to 3.41; P<0.001). Although formal interaction testing was negative (P=0.275), among patients with a nonischemic etiology of heart failure, the relative risk of death for men versus women was 3.08 (95% CI 1.56 to 6.09, P=0.001), whereas among those with ischemic heart disease, the relative risk of death for men versus women was 1.64 (95% CI 0.87 to 3.09, P=0.127). CONCLUSIONS: Women with advanced heart failure appear to have better survival than men. Subgroup analysis suggests this finding is strongest among patients with a nonischemic etiology of heart failure.


Assuntos
Baixo Débito Cardíaco/fisiopatologia , Caracteres Sexuais , Idoso , Baixo Débito Cardíaco/mortalidade , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Modelos de Riscos Proporcionais , Fatores de Risco , Análise de Sobrevida
17.
J Am Coll Cardiol ; 12(6 Suppl A): 32A-43A, 1988 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2973487

RESUMO

In patients with acute myocardial infarction presenting to community hospitals, thrombolytic therapy should be initiated as rapidly as possible under the supervision of a physician. Paramedic or nurse-initiated pre-hospital therapy is currently investigational. Each hospital must have a detailed evaluation and treatment protocol for acute myocardial infarction that specifies the timetable for patient evaluation, who should or should not receive thrombolytic therapy and the proper dose and mode of administration of the agent or agents to be used. Monitoring after the administration of thrombolytic therapy should focus on arrhythmias, hemodynamic problems, recurrent ischemia and bleeding. The role of early cardiac catheterization to detect patients who have unsuccessful thrombolysis or who require mechanical revascularization procedures is under active investigation. The design of the Thrombolysis and Angioplasty in Acute Myocardial Infarction (TAMI) 5 study, which addresses the role of acute interventional catheterization in the treatment of patients with acute myocardial infarction, is described.


Assuntos
Fibrinolíticos/administração & dosagem , Hospitais Comunitários , Infarto do Miocárdio/tratamento farmacológico , Angioplastia com Balão , Arritmias Cardíacas/etiologia , Doença das Coronárias/etiologia , Emergências , Fibrinolíticos/efeitos adversos , Fibrinolíticos/uso terapêutico , Hemorragia/etiologia , Humanos , Hipotensão/etiologia , Monitorização Fisiológica , Infarto do Miocárdio/mortalidade , Transferência de Pacientes , Recidiva , Fatores de Tempo
18.
J Am Coll Cardiol ; 23(1): 11-8, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8277068

RESUMO

OBJECTIVES: We designed a randomized trial to evaluate the effects of heparin administration in conjunction with anistreplase (anisoylated plasminogen streptokinase activator complex [APSAC]) on arterial patency and clinical end points. BACKGROUND: The role of conjunctive intravenous heparin therapy with APSAC has not been tested despite the recommendations that intravenous heparin should be used. METHODS: Four hours after APSAC administration, 250 patients with acute myocardial infarction were randomly assigned to receive 325 mg of either aspirin alone or aspirin and a continuous infusion of heparin (15 IU/kg body weight per h). Clinical ischemic events and bleeding complications were monitored. On hospital day 5, coronary arteriography and left ventriculography were performed. RESULTS: The primary end point of the trial (the combined outcome of death, reinfarction, recurrent ischemia and occlusion of the infarct-related artery) occurred in 42% of the heparin-treated group versus 43% of the group treated without heparin (p = 0.94). A patent infarct-related artery was present in 80% of the patients treated with heparin and in 73% of those treated without heparin (p = 0.26). Left ventricular function, as measured by ejection fraction, was well preserved in both groups (52% vs. 50.5%, respectively, p = 0.29). The overall bleeding rate was higher in patients with (32%) than without (17.2%) heparin (p = 0.006). CONCLUSIONS: Weight-adjusted intravenous heparin therapy after APSAC in acute myocardial infarction does not reduce the combined incidence of death, reinfarction, recurrent ischemia and occlusion of the infarct-related artery. Furthermore, withholding intravenous heparin therapy is associated with a 46% reduction in bleeding complications. Our findings do not support the addition of intravenous heparin after APSAC therapy, as currently recommended, and suggest that a strategy of withholding heparin is simpler and safer and does not place the patient at increased risk for ischemic complications after myocardial infarction.


Assuntos
Anistreplase/uso terapêutico , Heparina/uso terapêutico , Infarto do Miocárdio/tratamento farmacológico , Terapia Trombolítica/métodos , Idoso , Quimioterapia Combinada , Feminino , Heparina/administração & dosagem , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Tempo de Tromboplastina Parcial , Terapia Trombolítica/efeitos adversos , Falha de Tratamento , Grau de Desobstrução Vascular/efeitos dos fármacos
19.
J Am Coll Cardiol ; 30(4): 1002-8, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9316531

RESUMO

OBJECTIVES: We sought to characterize the clinical determinants of mortality in patients with angiographically diagnosed ischemic or nonischemic cardiomyopathy. BACKGROUND: Patients with ischemic cardiomyopathy may have a worse prognosis than patients with nonischemic cardiomyopathy. Few studies have assessed the effect of ischemic versus nonischemic etiology on outcomes. METHODS: We analyzed prospectively collected data on 3,787 patients with a left ventricular ejection fraction < or = 40% who underwent coronary angiography. Patients were considered to have ischemic cardiomyopathy (n = 3,112) if they had a history of myocardial infarction, percutaneous transluminal coronary angioplasty, coronary artery bypass graft surgery or at least one major epicardial coronary artery with > or = 75% stenosis; all others were considered to have nonischemic cardiomyopathy (n = 675). RESULTS: The median age, ejection fraction and proportion of patients with New York Heart Association functional class III or IV symptoms for the nonischemic and ischemic groups were 55 years versus 63 years, 27% versus 32% and 57% versus 25%, respectively. After adjustment for baseline clinical risk factors and presenting characteristics, ischemic etiology remained an important independent predictor of 5-year mortality (p < 0.0001). The extent of coronary artery disease was a better predictor of survival than ischemic or nonischemic etiology (log likelihood chi-square 700 vs. 675, respectively). CONCLUSIONS: Ischemic etiology is a significant independent predictor of mortality in patients with cardiomyopathy. However, the extent of coronary artery disease contributes more prognostic information than the clinical diagnosis of ischemic or nonischemic cardiomyopathy. Further research is needed to refine the clinical definition of ischemic cardiomyopathy so that physicians can appropriately prescribe treatment and accurately predict outcome.


Assuntos
Cardiomiopatias/etiologia , Cardiomiopatias/mortalidade , Doença das Coronárias/complicações , Adulto , Idoso , Cateterismo Cardíaco , Cardiomiopatias/diagnóstico , Cardiomiopatias/fisiopatologia , Distribuição de Qui-Quadrado , Angiografia Coronária , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Fatores de Risco , Volume Sistólico , Análise de Sobrevida , Função Ventricular Esquerda
20.
J Am Coll Cardiol ; 36(2): 541-6, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10933370

RESUMO

OBJECTIVE: The purpose of this study was to address the timing of sudden death in advanced heart failure patients. BACKGROUND: Sudden death is a catastrophic event in cardiovascular disease. It has a circadian pattern prominent in the early AM, which has been thought to be due to a surge of sympathetic stimulation. We postulated that the distribution of events in advanced heart failure, with chronic sympathetic activation, would be more uniform implicating other potential mechanisms. METHODS: We analyzed data from Prospective Randomized Amlodipine Survival Trial (PRAISE). Sudden deaths were analyzed by time of death in 4-h and 1-h blocks for uniformity of distribution in the entire cohort, and in the prespecified ischemic and nonischemic stratum. Further analyses were undertaken in the treatment groups of amlodipine and placebo, and among those receiving background therapy of aspirin and warfarin. RESULTS: Sudden deaths in the overall cohort showed a nonuniform distribution with a PM peak but not an AM peak. The ischemic stratum also showed a PM peak, but sudden deaths within the nonischemic stratum were uniformly distributed. Neither amlodipine treatment nor aspirin or warfarin use altered the distribution. CONCLUSIONS: Sudden death in advanced heart failure did not show an AM peak, suggesting that circadian sympathetic activation did not strongly influence these events. The PM peak noted is likely complex in origin and was not affected by antiischemic or antithrombotic medications.


Assuntos
Ritmo Circadiano , Morte Súbita Cardíaca , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anlodipino/uso terapêutico , Bloqueadores dos Canais de Cálcio/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos
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