Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 34
Filtrar
1.
Trends Ecol Evol ; 36(5): 430-443, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33549373

RESUMO

Melanins are widespread pigments in vertebrates, with important roles in visual signaling, UV protection, and homeostasis. Fossil evidence of melanin and melanin-bearing organelles - melanosomes - in ancient vertebrates may illuminate the evolution of melanin and its functions, but macroevolutionary trends are poorly resolved. Here, we integrate fossil data with current understanding of melanin function, biochemistry, and genetics. Mapping key genes onto phenotypic attributes of fossil vertebrates identifies potential genomic controls on melanin evolution. Taxonomic trends in the anatomical location, geometry, and chemistry of vertebrate melanosomes are linked to the evolution of endothermy. These shifts in melanin biology suggest fundamental links between melanization and vertebrate ecology. Tissue-specific and taxonomic trends in melanin chemistry support evidence for evolutionary tradeoffs between function and cytotoxicity.


Assuntos
Melaninas , Vertebrados , Animais , Fósseis , Melanossomas , Pigmentação/genética , Vertebrados/genética
2.
Dis Aquat Organ ; 91(2): 167-75, 2010 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-21387996

RESUMO

Coral diseases have caused significant losses on Caribbean reefs and are becoming a greater concern in the Pacific. Progress in coral disease research requires collaboration and communication among experts from many different disciplines. The lack of consistency in the use of terms and names in the recent scientific literature reflects the absence of an authority for naming coral diseases, a lack of consensus on the meaning of even some of the most basic terms as they apply to corals, and imprecision in the use of descriptive words. The lack of consensus partly reflects the complexity of this newly emerging field of research. Establishment of a nomenclature committee under the Coral Disease and Health Consortium (CDHC) could lead to more standardized definitions and could promote use of appropriate medical terminology for describing and communicating disease conditions in corals. This committee could also help to define disease terminology unique to corals where existing medical terminology is not applicable. These efforts will help scientists communicate with one another and with the general public more effectively. Scientists can immediately begin to reduce some of the confusion simply by explicitly defining the words they are using. In addition, digital photographs can be posted on the CDHC website and included in publications to document the macroscopic (gross) signs of the conditions observed on coral colonies along with precisely written characterizations and descriptions.


Assuntos
Antozoários/microbiologia , Terminologia como Assunto , Animais , Ecossistema
3.
Vet Immunol Immunopathol ; 128(1-3): 147-70, 2009 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-19056129

RESUMO

The ability to identify factors responsible for disease in all species depends on the ability to separate those factors which are environmental from those that are intrinsic. This is particularly important for studies on the development of the adaptive immune response of neonates. Studies on laboratory rodents or primates have been ambiguous because neither the effect of environmental nor maternal factors on the newborn can be controlled in mammals that: (i) transmit potential maternal immunoregulatory factors in utero and (ii) are altricial and cannot be reared after birth without their mothers. Employing the newborn piglet model can address each of these concerns. However, it comes at the price of having first to characterize the immune system of swine and its development. This review focuses on the porcine B cell system, especially on the methods used for its characterization in fetal studies and neonatal piglets. Understanding these procedures is important in the interpretation of the data obtained. Studies on neonatal piglets have (a) provided valuable information on the development of the adaptive immune system, (b) lead to important advances in evolutionary biology, (c) aided our understanding of passive immunity and (d) provided opportunities to use swine to address specific issues in veterinary and biomedical research and immunotherapy. This review summarizes the history of the development of the piglet as a model for antibody repertoire development, thus providing a framework to guide future investigators.


Assuntos
Linfócitos B/fisiologia , Sistema Imunitário/crescimento & desenvolvimento , Modelos Animais , Suínos/crescimento & desenvolvimento , Suínos/imunologia , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Animais Recém-Nascidos/imunologia , Vida Livre de Germes , Humanos , Suínos/embriologia
4.
J Thorac Cardiovasc Surg ; 130(1): 20-8, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15999036

RESUMO

OBJECTIVE: We evaluated, in a randomized controlled trial, the safety and effectiveness of intraoperative cell salvage and autotransfusion of washed salvaged red blood cells after first-time coronary artery bypass grafting performed on the beating heart. METHODS: Sixty-one patients undergoing off-pump coronary artery bypass grafting surgery were prospectively randomized to autotransfusion (n = 30; receiving autotransfused washed blood from intraoperative cell salvage) or control (n = 31; receiving homologous blood only as blood-replacement therapy). Homologous blood was given according to unit protocols. RESULTS: The groups were well matched with respect to demographic and comorbid characteristics. Patients in the autotransfusion group had a significantly higher 24-hour postoperative hemoglobin concentration (11.9 g/dL; SD, 1.41 g/dL) than those in the control group (10.5 g/dL; SD, 1.37 g/dL) (mean difference, 1.02 g/dL; 95% confidence interval, 1.60-0.44 g/dL; P = .0007), as well as a 20% reduction in the frequency of homologous blood product use (11/31 vs 5/30; P = .095). Autotransfusion of washed red blood cells was not associated with any derangement of thromboelastograph values or laboratory measures of clotting pathway function (prothrombin time, activated partial thromboplastin time, and fibrinogen levels), increased postoperative bleeding, fluid requirements, or adverse clinical events. There was no statistical difference between groups in the total operation, hospitalization, and management costs per patient (median difference, USD 1015.90; 95% confidence interval, -USD 2260 to USD 206; P = .11). Conclusions Intraoperative cell salvage and autotransfusion was associated with higher postoperative hemoglobin concentrations, a modest reduction in transfusion requirements, no adverse clinical or coagulopathic effects, and no significant increase in cost compared with controls. This study supports its routine use in off-pump coronary artery bypass grafting surgery.


Assuntos
Transfusão de Sangue Autóloga , Ponte de Artéria Coronária sem Circulação Extracorpórea , Adulto , Idoso , Transfusão de Sangue Autóloga/economia , Ponte de Artéria Coronária sem Circulação Extracorpórea/economia , Doença das Coronárias/cirurgia , Feminino , Hemoglobinas/análise , Hemostasia Cirúrgica , Humanos , Período Intraoperatório , Masculino , Contagem de Plaquetas
5.
Science ; 289(5478): 391, 2000 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-10939946
6.
Science ; 289(5478): 391b, 2000 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-17840574
7.
Eur J Pharmacol ; 293(4): 475-81, 1995 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-8748701

RESUMO

We studied the effects of ibuprofen on bronchial blood flow and myocardial function after inhalation injury. Sheep (n = 12) were chronically instrumented with cardiovascular and pulmonary catheters. After 5 days of recovery period, baseline data were collected and the sheep were divided into two groups. Group S (n = 6) were insufflated with 48 breaths of cotton smoke; while group I (n = 6) were pretreated with ibuprofen (12mg/kg bolus followed by 3 mg/kg/h continuous infusion for 24 h) and challenged with the same dose of smoke. All the animals were studied for 24h. Bronchial blood flow increased significantly in both groups throughout the experimental period; while stroke volume as well as right and left ventricular stroke work indices of both groups were significantly decreased (group I worse than group S) in the second half of the experimental period. These data suggest that vasodilatory prostaglandins do not play a major role in the bronchial vascular response to smoke inhalation injury and myocardial depression seen post injury is worse in animals treated with ibuprofen.


Assuntos
Artérias Brônquicas/efeitos dos fármacos , Inibidores de Ciclo-Oxigenase/farmacologia , Ibuprofeno/farmacologia , Lesão por Inalação de Fumaça/fisiopatologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Temperatura Corporal/efeitos dos fármacos , Débito Cardíaco/efeitos dos fármacos , Gossypium , Frequência Cardíaca/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Troca Gasosa Pulmonar/efeitos dos fármacos , Ovinos , Volume Sistólico/efeitos dos fármacos
8.
Diabetes Educ ; 21(4): 297-9, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7621731

RESUMO

This article describes the particular relevance of Erik Erikson's psychosocial stages of development for children with insulin-dependent diabetes. The developmental issues for young children centering on trust, autonomy, initiative, and industry have special significance for children with diabetes. Although the issues faced in each of Erikson's psychosocial stages are present in every stage, behaviors are manifested differently at each stage. Practical suggestions are provided for families and healthcare providers living with or working with children of various ages who have diabetes.


Assuntos
Desenvolvimento Infantil , Diabetes Mellitus Tipo 1/psicologia , Adolescente , Fatores Etários , Criança , Pré-Escolar , Humanos , Lactente , Educação de Pacientes como Assunto , Teoria Psicológica , Autocuidado/psicologia
9.
Circ Shock ; 38(1): 34-41, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1394862

RESUMO

We have previously reported an increase in plasma levels of atrial natriuretic factor (ANF) in an ovine model of endotoxemia. The purpose of this study was to determine if this IR-ANF release was mediated by the increase of right atrial pressure (RAP) and right heart volumes concomitantly observed following endotoxin (LPS) administration. We studied right ventricular function, renal blood flow (RBF), urinary output (UO), urinary clearance of free water (CH20), urinary osmolality (UOSM), sodium excretion (UENA), and the plasma IR-ANF concentration (radioimmunoassay), following the administration of an E. coli LPS bolus (1 microgram/kg) with (group O, n = 8) and without (group E, n = 10) pretreatment with OKY-046, a selective thromboxane synthetase inhibitor. LPS induced early increases in RAP, right ventricular end-systolic (RVESV) and end-diastolic (RVEDV) volumes, heart rate (HR), and IR-ANF, and delayed increases in RBF, UO, and CH20. OKY-046 prevented the elevation of RAP, RVEDV, and RVESV; however, both groups showed virtually identical increases in IR-ANF (E: 20.03 +/- 3.8 to 192.33 +/- 35.47 pg/ml, O: 17.9 +/- 4.1 to 159.5 +/- 23 pg/ml) as well as an increase of HR, RBF, UO, and CH20. The increase in IR-ANF release noted following the administration of LPS in an ovine model does not appear to be related to the early elevations in right heart volumes or atrial distension.


Assuntos
Fator Natriurético Atrial/metabolismo , Endotoxinas/sangue , Toxemia/fisiopatologia , Animais , Pressão Sanguínea , Débito Cardíaco , Modelos Animais de Doenças , Diurese , Frequência Cardíaca , Lipopolissacarídeos/farmacologia , Metacrilatos/farmacologia , Natriurese , Concentração Osmolar , Circulação Renal , Ovinos , Tromboxano-A Sintase/antagonistas & inibidores , Toxemia/sangue , Urina , Resistência Vascular , Função Ventricular Direita
10.
J Trauma ; 32(6): 704-12; discussion 712-3, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1377286

RESUMO

We compared the effects of lactated Ringer's (LR) and hypertonic saline dextran (HSD) on postburn cardiovascular function, O2 consumption, lipid peroxidation, and bacterial translocation. Miniature pigs with 40% total body surface area (TBSA), third-degree burns received, 30 minutes postburn, either Parkland resuscitation (LR group, n = 8) or HSD, 10 mL/kg/30 minutes, followed by LR, 4 mL/kg/%burn over the next 23 hours (HSD group, n = 8). The HSD prevented the early decrease in cardiac index (CI); the early increase in the resistance of the systemic, mesenteric, celiac, and renal vascular beds; and the decrease in mesenteric O2 consumption seen after burns when LR alone is used for resuscitation. The HSD also moderated the systemic and mesenteric lipid peroxidation. Bacterial translocation was less in the HSD group (3 of 8 animals) compared with the LR group (5 of 8 animals), but was not statistically different. Hypertonic saline dextran may be beneficial in improving the postburn microcirculation and attenuating postburn oxidant-induced lipid peroxidation in the systemic tissues and the gut.


Assuntos
Queimaduras/terapia , Reanimação Cardiopulmonar/métodos , Dextranos/uso terapêutico , Soluções Isotônicas/uso terapêutico , Peroxidação de Lipídeos/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , Solução Salina Hipertônica/uso terapêutico , Animais , Bactérias/efeitos dos fármacos , Gasometria , Queimaduras/metabolismo , Queimaduras/fisiopatologia , Reanimação Cardiopulmonar/normas , Movimento Celular/efeitos dos fármacos , Contagem de Colônia Microbiana , Dextranos/farmacologia , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Estrogênios Conjugados (USP) , Feminino , Hemodinâmica/efeitos dos fármacos , Soluções Isotônicas/farmacologia , Mesentério/irrigação sanguínea , Mesentério/efeitos dos fármacos , Microcirculação/efeitos dos fármacos , Circulação Renal/efeitos dos fármacos , Traumatismo por Reperfusão/sangue , Traumatismo por Reperfusão/etiologia , Lactato de Ringer , Solução Salina Hipertônica/farmacologia , Circulação Esplâncnica/efeitos dos fármacos , Suínos , Porco Miniatura , Resistência Vascular/efeitos dos fármacos
12.
J Gen Intern Med ; 6(1): 9-17, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1999752

RESUMO

STUDY OBJECTIVE: To evaluate the effectiveness of two teaching interventions to increase residents' performance of smoking cessation counseling. DESIGN: Randomized controlled factorial trial. SETTING: Eleven residency programs, in internal medicine (six), family medicine (three), and pediatrics (two). Programs were located in three university medical centers and four university-affiliated community hospitals. PARTICIPANTS: 261 residents who saw ambulatory care patients at least one half-day per week, and 937 returning patients aged 17 to 75 years who reported having smoked five or more cigarettes in the preceding seven days. Of the 937, 843 were eligible for follow-up, and 659 (78%) were interviewed by phone at six months. INTERVENTIONS: Two interventions (tutorial and prompt) and four groups. The tutorial was a two-hour educational program in minimal-contact smoking cessation counseling for residents. The prompt was a chart-based reminder to assist physician counseling. One group of residents received the tutorial; one, the prompt; and one, both. A fourth group received no intervention. MEASUREMENT AND RESULTS: Six months after the intervention, physician self-reports showed that residents in the tutorial + prompt and tutorial-only groups had used more counseling techniques (1.5-1.9) than had prompt-only or control residents (0.9). Residents in all three intervention groups advised more patients to quit smoking (76-79%) than did control group residents (69%). The tutorial had more effect on counseling practices than did the prompt. Physician confidence, perceived preparedness, and perceived success followed similar patterns. Exit interviews with 937 patients corroborated physician self-reports of counseling practices. Six months later, self-reported and biochemically verified patient quitting rates for residents in the three intervention groups (self-reported: 5.3-8.2%; biochemically verified: 3.4-5.7%) were higher than those for residents in the control group (self-reported: 5.2%; biochemically verified: 1.7%), though the differences were not statistically significant. CONCLUSION: A simple and feasible educational intervention can increase residents' smoking cessation counseling.


Assuntos
Aconselhamento/educação , Internato e Residência , Relações Médico-Paciente , Prevenção do Hábito de Fumar , Ensino/métodos , Estudos de Avaliação como Assunto , Medicina de Família e Comunidade/educação , Humanos , Medicina Interna/educação , Pediatria/educação
13.
J Gen Intern Med ; 5(3): 198-202, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2341918

RESUMO

Leukocyte (WBC) and differential counts are commonly used, but their clinical characteristics are poorly understood. To understand how the clinician interprets the WBC count in the presence of these uncertainties, the authors used a case vignette with a questionnaire to isolate physician reaction to an abnormal WBC count as compared with a normal control WBC count. In response to a case vignette of a urinary tract infection in the emergency room, physicians altered their diagnostic and therapeutic plans based solely on the WBC count. The results of the study also suggest that the cost of the WBC is not limited to the test cost, but also includes the cost of the physician reaction to the abnormal WBC count.


Assuntos
Serviço Hospitalar de Emergência , Contagem de Leucócitos , Infecções Urinárias/sangue , Atitude do Pessoal de Saúde , Custos e Análise de Custo , Testes Diagnósticos de Rotina/economia , Humanos , North Carolina , Inquéritos e Questionários
16.
Proc Natl Acad Sci U S A ; 86(23): 9342-6, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16594090

RESUMO

During the late summer to fall of 1987, Caribbean reef corals experienced an intense and widespread discoloration event described as bleaching. Contrary to initial predictions, most bleached corals did not die. However, energy input from zooxanthellae decreased, as estimated from: (i) delta(13)C values, a measure of the discrimination against (13)C in (12)C/(13)C assimilation, of skeletal aragonite; (ii) in situ photosynthesis-irradiance measurements; (iii) and tissue biomass parameters of Montastraea annularis and Agaricia lamarcki. The delta(18)O signal, a measure of the discrimination against (18)O in (16)O/(18)O assimilation, from M. annularis skeletons demonstrated that this event coincided with abnormally elevated water temperatures.

17.
Arch Intern Med ; 148(11): 2469-73, 1988 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3190379

RESUMO

Residents in primary care specialties care for many patients who smoke cigarettes, but little is known about their smoking cessation counseling (SCC). We surveyed 309 residents (72 family practice, 171 internal medicine, and 66 pediatrics residents) in 13 programs to determine their practices, knowledge, attitudes, and training in SCC. More than 90% thought physicians are responsible for SCC, the majority routinely took smoking histories, and 80% attempted to motivate patients to quit smoking. However, 25% or fewer reported discussing obstacles to quitting, setting a quit date, prescribing nicotine gum, scheduling follow-up visits, or providing self-help materials. Family practice residents used more SCC techniques (1.8) than did internal medicine (0.8) and pediatrics (0.1) residents. Only 54% of residents reported recent SCC training and 13% reported formal SCC training. Recent training correlated with the number of counseling techniques used. Residents in primary care specialties report positive attitudes but inadequate practice and training in SCC.


Assuntos
Internato e Residência , Medicina , Educação de Pacientes como Assunto , Prevenção do Hábito de Fumar , Especialização , Atitude do Pessoal de Saúde , Educação Médica , Medicina de Família e Comunidade/educação , Humanos , Medicina Interna/educação , Pediatria/educação , Inquéritos e Questionários
19.
Ann Emerg Med ; 16(4): 445-6, 1987 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3826816

RESUMO

Two cases of patients with acute airway compromise due to benign tracheal mucocele are presented. In each, the diagnosis was made by flexible fiberoptic bronchoscopy. Each patient developed the acute episode at 12 months of age following an upper airway infection. The mucoceles were "unroofed" and drained through rigid bronchoscopes. Both patients had been intubated following premature birth; trauma to the tracheal mucosa is proposed as the etiologic factor in the development of these mucoceles.


Assuntos
Obstrução das Vias Respiratórias/etiologia , Mucocele/complicações , Doenças da Traqueia/complicações , Doença Aguda , Emergências , Humanos , Lactente , Intubação Intratraqueal/efeitos adversos , Masculino , Traqueia/lesões
20.
Int J Obes ; 11(1): 73-83, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3570639

RESUMO

Children's thoughts about human fatness were studied in interviews with children (n = 96) of three age groups (4-5 years, 8-9 years, and 12-13 years). Using a Piagetian theoretical framework, tasks were devised to measure concepts of body identity and causes of obesity which could be compared to measures of physical conservation and physical causality. Older children demonstrated higher levels of reasoning on all tasks than did younger children, with significant differences between each age group for each of four tasks (P less than 0.001). Correlations between tasks were high across all subjects but moderate within age groups. Body identity was understood at higher levels than was physical conservation (P less than 0.0001) among only the youngest group. The levels of understanding causes of fatness and of other natural physical events were not different in the youngest group. However, physical causality was understood and at a higher level than obesity causality among both the 8- to 9-year-olds (P less than 0.0001) and 12- to 13-year-olds (P less than 0.0001). Body identity and obesity causality scores were significantly different only among 12- to 13-year-olds at which time identity scores were higher (P less than 0.003). Physical causality was understood at higher levels than physical conservation among all age groups.


Assuntos
Cognição , Obesidade/psicologia , Psicologia da Criança , Adolescente , Imagem Corporal , Criança , Pré-Escolar , Humanos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...