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1.
Br J Cancer ; 96(5): 752-7, 2007 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-17299389

RESUMO

The risk of suicide in cancer patients has been reported as elevated in several countries. These patients are exposed to many medicines that may confuse or provide a means for harm, potentially also increasing their risk from accidents. Ratios of observed/expected numbers of hospital admission and death events relating to deliberate self-harm (DSH) and accidents were calculated in the 5 years from a cancer diagnosis in Scotland 1981-1995, compared to the matched general population. The relative risk (RR) of suicide was 1.51 (95% confidence interval (CI): 1.29-1.76). The RR of hospital admissions for DSH was not significantly increased, suggesting a strong suicidal intent in DSH acts in cancer patients. Accidental poisonings and all other accidents were both increased (RR death=3.69, 95% CI: 2.10-6.00; and 1.58, 95% CI: 1.48-1.69, respectively) (RR hospital admissions=1.32, 95% CI: 1.19-1.47; and 1.55, 95% CI: 1.53-1.57, respectively). The association of only certain tumour types (e.g. respiratory) with suicide and accidental poisoning, and a broad range of tumour types with an elevated risk of all other accidents, suggests accidental poisoning categories may be a common destination for code shifting of some DSH events. A previous history of DSH or accidents, significantly increased the RR of suicide or fatal accidents, respectively (RR suicide=14.86 (95% CI: 4.69-34.97) vs 1.16 (95% CI: 0.84-1.55)) (RR accidental death=3.37 (95% CI: 2.53-4.41) vs 1.29 (95% CI: 1.12-1.49)). Within 5 years of a cancer diagnosis, Scottish patients are at increased RR of suicide and fatal accidents, and increased RR of hospital admissions for accidents. Some of these accidents, particularly accidental poisonings, may contain hidden deliberate acts. Previous DSH or accidents are potential markers for those most at risk, in whom to target interventional techniques.


Assuntos
Acidentes/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Mortalidade , Neoplasias/psicologia , Suicídio/estatística & dados numéricos , Adolescente , Adulto , Fatores Etários , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Risco , Escócia
2.
Heart ; 92(11): 1563-70, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16775090

RESUMO

OBJECTIVE: To analyse short- and long-term outcomes and prognostic factors in a large population-based cohort of unselected patients with a first emergency admission for suspected acute coronary syndrome between 1990 and 2000 in Scotland. METHODS: All first emergency admissions for acute myocardial infarction (AMI) and all first emergency admissions for angina (the proxy for unstable angina) between 1990 and 2000 in Scotland (population 5.1 million) were identified. Survival to five years was examined by Cox multivariate modelling to examine the independent prognostic effects of diagnosis, age, sex, year of admission, socioeconomic deprivation and co-morbidity. RESULTS: In Scotland between 1990 and 2000, 133,429 individual patients had a first emergency admission for suspected acute coronary syndrome: 96 026 with AMI and 37,403 with angina. After exclusion of deaths within 30 days, crude five-year case fatality was similarly poor for patients with angina and those with AMI (23.9% v 21.6% in men and 23.5% v 26.0% in women). The longer-term risk of a subsequent fatal or non-fatal event in the five years after first hospital admission was high: 54% in men after AMI (53% in women) and 56% after angina (49% in women). Event rates increased threefold with increasing age and 20-60% with different co-morbidities, but were 11-34% lower in women. CONCLUSIONS: Longer-term case fatality was similarly high in patients with angina and in survivors of AMI, about 5% a year. Furthermore, half the patients experienced a fatal or non-fatal event within five years. These data may strengthen the case for aggressive secondary prevention in all patients presenting with acute coronary syndrome.


Assuntos
Angina Pectoris/mortalidade , Infarto do Miocárdio/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Emergências/epidemiologia , Tratamento de Emergência/mortalidade , Métodos Epidemiológicos , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Revascularização Miocárdica/mortalidade , Prognóstico , Escócia , Distribuição por Sexo
5.
Inhal Toxicol ; 16(10): 721-9, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15371059

RESUMO

Dodecanediamine (DDDA) is used in the production of specialty polymers. Exposure to this chemical was associated with dermal sensitization in pilot-plant workers, and the possibility that the chemical could produce dermal sensitization was confirmed in a guinea pig test. This property and its dermal irritative properties demonstrate the need to limit skin contact. The possibility of exposure via inhalation also exists. Although stable under ambient conditions, DDDA is processed at elevated temperatures where it may fume, forming a carbamate after reaction with atmospheric carbon dioxide. Some of the carbamate may be converted back to the diamine after hydrolysis in tissue. The rat was used to evaluate the effects of both acute and repeated exposure following inhalation. Fumed DDDA was found to be moderately toxic following a single 4-h exposure with lethality seen at concentrations of 680 mg/m3 or higher. Rats were then exposed to concentrations of either 0 (control), 11, 34, or 98 mg fumed DDDA/m3, 6 h/day, 5 days/wk for 2 wk. Mortality was seen at the highest concentrations, along with increased lung weights. In these rats, laryngeal and tracheal lesions consisting of acute necrosis and inflammation were seen, but surviving rats given a 14-day recovery period showed almost complete recovery. Tracheal and laryngeal lesions were not seen in rats exposed to either 11 or 34 mg/m3. Degenerative and necrotizing lesions were seen in the nasal regions, primarily the respiratory mucosa, of rats in all three treatment groups. The lesions were exposure related with regard to incidence and severity, but regeneration was seen following the recovery period. No evidence of systemic toxicity was seen. The dose-response characteristics of the nasal lesions and the sensitization potential suggest that workplace control levels of 0.1 mg/m3 should be sufficient to protect workers against the untoward effects of fumed DDDA.


Assuntos
Poluentes Ocupacionais do Ar/toxicidade , Diaminas/toxicidade , Sistema Respiratório/efeitos dos fármacos , Administração por Inalação , Animais , Diaminas/administração & dosagem , Relação Dose-Resposta a Droga , Exposição por Inalação , Laringe/efeitos dos fármacos , Laringe/patologia , Longevidade/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Pulmão/patologia , Masculino , Mucosa Nasal/efeitos dos fármacos , Mucosa Nasal/patologia , Necrose , Tamanho do Órgão/efeitos dos fármacos , Ratos , Mucosa Respiratória/efeitos dos fármacos , Mucosa Respiratória/patologia , Sistema Respiratório/patologia , Traqueia/efeitos dos fármacos , Traqueia/patologia , Volatilização
6.
Br J Cancer ; 91(3): 459-65, 2004 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-15226766

RESUMO

Pancreatic cancer is associated with a very poor prognosis; however, in selected patients, resection may improve survival. Several recent reports have demonstrated that concentration of treatment activity for patients with pancreatic cancer has resulted in improved outcomes. The aim of this study was to ascertain if there was any evidence of benefit for specialised care of patients with pancreatic cancer in Scotland. Records of patients diagnosed with pancreatic cancer during the period 1993-1997 were identified. Three indicators of co-morbidity were calculated for each patient. Operative procedures were classified as resection, other surgery or biliary stent. Prior to analysis, consultants were assigned as specialist pancreatic surgeons, clinicians with an interest in pancreatic disease or nonspecialists. Data were analysed with regard to 30-day mortality and survival outcome. The final study population included 2794 patients. The 30-day mortality following resection was 8%, and hospital or consultant volume did not affect postoperative mortality. The 30-day mortality rate following palliative surgical operations was 20%, and consultants with higher case loads or with a specialist pancreatic practice had significantly fewer postoperative deaths (P=0.014 and 0.002, respectively). For patients undergoing potentially curative or palliative surgery, the adjusted hazard of death was higher in patients with advanced years, increased co-morbidity, metastatic disease, and was lower for those managed by a specialist (RHR 0.63, 95% CI 0.50-0.78) or by a clinician with an interest in pancreatic disease (RHR 0.63, 0.48-0.82). The risk of death 3 years after diagnosis of pancreatic cancer is higher among patients undergoing surgical intervention by nonspecialists. Specialisation and concentration of cancer care has major implications for the delivery of health services.


Assuntos
Oncologia/normas , Medicina/normas , Neoplasias Pancreáticas/cirurgia , Especialização , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Comorbidade , Feminino , Hospitais/estatística & dados numéricos , Humanos , Lactente , Recém-Nascido , Masculino , Auditoria Médica , Pessoa de Meia-Idade , Cuidados Paliativos , Prognóstico , Qualidade da Assistência à Saúde , Estudos Retrospectivos , Medição de Risco , Escócia
8.
Inhal Toxicol ; 16(9): 581-92, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16036751

RESUMO

Dimethyl sulfate (DMS) is an alkylating agent that is carcinogenic to the respiratory tract of rodents. DNA adducts, cell proliferation, and histopathology were assessed in rats to better understand the molecular dosimetry and tissue dynamics associated with repeated inhalation exposure to DMS. For DNA methylation, rats were exposed to DMS vapor 6 h/day for up to 10 days to 0.0, 0.1, 0.7 and 1.5 ppm. N7-Methylguanine and N3-methyladenine were detected in neutral thermal hydrolysates of DNA isolated from respiratory tract tissues by high-performance liquid chromatography (HPLC) using fluorescence and ultraviolet (UV) detection. DNA methylation was greatest in DNA isolated from nasal respiratory mucosa, less in olfactory, and little was found in lung. N7-Methylguanine levels in respiratory mucosa approached steady-state levels by day 5, and N7-methylguanine persistence following exposure for 5 consecutive days was also determined. Loss of N7-methylguanine from respiratory and olfactory mucosa appeared to follow first-order kinetics. N3-Methyladenine levels were at or below detection limits in all samples. The effect of DMS on histopathology and cell proliferation in the nasal epithelium was also investigated. Rats were exposed nose-only for 2 wk to DMS vapor at concentrations of 0, 0.1, 0.7, or 1.5 ppm. Inhalation exposure to DMS induced degenerative and inflammatory changes in nasal epithelium at >or=0.7 ppm. Cell proliferation evaluations showed a trend towards an increased response at 1.5 ppm. These experiments demonstrate that DMS can induce cytotoxic and proliferative effects and is a potent methylating agent of the nasal mucosa in vivo. These experiments will provide data for the development of dosimetry models useful for risk extrapolation.


Assuntos
Adenina/análogos & derivados , Alquilantes/toxicidade , Proliferação de Células/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Guanina/análogos & derivados , Mutagênicos/toxicidade , Ésteres do Ácido Sulfúrico/toxicidade , Adenina/metabolismo , Administração por Inalação , Alquilantes/administração & dosagem , Alquilantes/farmacocinética , Animais , Peso Corporal/efeitos dos fármacos , DNA/metabolismo , Adutos de DNA/metabolismo , Guanina/metabolismo , Masculino , Metilação , Modelos Biológicos , Mutagênicos/administração & dosagem , Mutagênicos/farmacocinética , Mucosa Olfatória/patologia , Purinas/metabolismo , Ratos , Risco , Ésteres do Ácido Sulfúrico/administração & dosagem , Ésteres do Ácido Sulfúrico/farmacocinética
9.
Drug Chem Toxicol ; 26(2): 99-115, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12816395

RESUMO

Methylglutaronitrile (MGN) is a high-boiling (263 degrees C) solvent/intermediate used in the fiber industry. Twenty male rats per group were exposed nose-only to condensation aerosol/vapor concentrations of approximately either 5, 25, or 200 mg/m3 of MGN for 6 h/day, 5 days/week over a 4-week period. Ten rats/group were sacrificed one day after the final exposure and the remaining rats after a four-week recovery period. No effects were observed in clinical observations during the exposure period, but body-weight depression was observed in the 200 mg/m3 group. The 200 mg/m3 group showed minimal decreases in red blood cell count, hemoglobin, and hematocrit values accompanied by increases in reticulocytes. There were no other effects observed in clinical or pathologic evaluations in the study. A neurobehavioral battery of tests (including grip strength, functional observational battery, and motor activity tests) given at the end of the exposure and recovery periods showed no MGN effects. During the 4-week recovery, body weights in the 200 mg/m3 group returned to normal and the hematologic findings in all groups were normal. Based on the above findings of body weight depression at 200 mg/m3, the no-observed-adverse-effect level (NOAEL) for this study was considered to be 25 mg/m3.


Assuntos
Glutaratos/toxicidade , Metemoglobina/análise , Nitrilas/toxicidade , Administração por Inalação , Animais , Câmaras de Exposição Atmosférica , Contagem de Células Sanguíneas , Peso Corporal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Glutaratos/administração & dosagem , Masculino , Atividade Motora/efeitos dos fármacos , Sistema Nervoso/efeitos dos fármacos , Nitrilas/administração & dosagem , Nível de Efeito Adverso não Observado , Tamanho do Órgão/efeitos dos fármacos , Ratos , Fatores Sexuais , Testes de Toxicidade Aguda , Testes de Toxicidade Crônica
10.
Drug Chem Toxicol ; 25(3): 255-66, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12173247

RESUMO

Some peroxisome proliferators have been reported to reduce body weight gain in suckling rats, possibly through a lactational effect. Decreases in milk production or nutritional quality, either as a result of peroxisome proliferator-induced reductions in lipid content or alterations in the hormonal milieu necessary for milk production, could result in pup growth retardation. Wyeth-14,643 (WY) is hypolipidemic agent and a potent inducer of hepatic peroxisome proliferation in rats and mice. As is commonly seen with rodent hepatic peroxisome proliferators, WY produces minimal or no peroxisome induction in guinea pigs or non-human primates. Goats are an excellent model for studying lactation, however, their sensitivity to peroxisome proliferating chemicals is not known. The present study was performed to assess the sensitivity of goats to the hypolipidemic and peroxisome proliferator properties of WY and to determine the effects of WY on milk quantity and quality. Six lactating adult female goats were assigned to either control or treated groups. Goats in the treated group were administered WY (40 mg/kg/day) for 14 consecutive days. The goats were milked twice daily in order to maintain lactation and the quantity of milk collected was recorded. Milk quality was evaluated by determining the content of total fat, protein, and carbohydrate in milk samples collected following 7 and 14 days of treatment. WY administration had no effects on final body weight, liver weight or, gross and histopathological findings. Milk quantity and quality were unaffected by treatment. Serum cholesterol and triglyceride levels were reduced by 25% compared to controls, although only the difference in cholesterol was statistically significant. Hepatic beta-oxidation (3 x control) and aromatase (1.5 x control) activities were significantly greater in the treatment group; however, there was no treatment-related effect in the total content of hepatic cytochrome P450. There was no difference in aromatase activity in a pooled ovarian microsome sample. Milk estradiol and prolactin concentrations were not affected by treatment. These findings indicate that goats are weak responders to the hepatic peroxisome proliferator effects of WY. Additionally, the slight serum hypolipidemic effect does not impact milk production or nutritional value.


Assuntos
Lactação/efeitos dos fármacos , Leite/química , Proliferadores de Peroxissomos/farmacologia , Pirimidinas/farmacologia , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Peso Corporal , Estradiol/análise , Feminino , Cabras , Lipídeos , Microcorpos , Ratos
11.
Toxicol Sci ; 67(2): 190-7, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12011478

RESUMO

Chronic administration of vinyl acetate (VA) in drinking water to rats and mice has produced upper digestive tract neoplasms. These tumors were believed to arise from the intracellular metabolism of VA by carboxylesterases to cytotoxic and genotoxic compounds. We hypothesized that prolonged VA exposure at high concentrations would induce cytotoxicity and a restorative cell proliferation (CP). These endpoints were measured in F-344 rats and BDF1 mice administered drinking water containing 0, 1000, 5000, 10,000, or 24,000 ppm VA for 92 days. On test days, Days 1, 8, 29, and 92, upper digestive tract histopathology and oral cavity CP (pulsed 5-bromodeoxyuridine [BrdU] to measure S-phase DNA synthesis) were evaluated. Analysis of test solutions showed that VA spontaneously hydrolyzed, slowly releasing acetic acid and thereby lowering pH. Statistically significant, concentration-related increases in CP occurred in basal cells of the mandibular oral cavity mucosa of mice at 10,000 and 24,000 ppm but only after 92 days. CP increases were approximately 2.4- and 3.4-fold above controls and were considered to be toxicologically significant. Some statistically significant increases in CP were also measured in the oral cavity mucosa of rats; however, these changes were considered to be of equivocal biological relevance. No histopathological evidence of mucosal injury was seen in either species. The absence of cytotoxicity in the upper digestive tract mucosa suggests that the increased CP at high administered VA concentrations may be due to a mitogenic response, ostensibly from the loss of cell growth controls in oral cavity mucosa.


Assuntos
Carcinógenos/toxicidade , Divisão Celular/efeitos dos fármacos , Compostos de Vinila/toxicidade , Administração Oral , Animais , Peso Corporal/efeitos dos fármacos , Bromodesoxiuridina/metabolismo , Carcinógenos/administração & dosagem , DNA/biossíntese , Relação Dose-Resposta a Droga , Ingestão de Líquidos , Esôfago/efeitos dos fármacos , Esôfago/metabolismo , Esôfago/patologia , Mucosa Gástrica/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos , Mucosa Bucal/efeitos dos fármacos , Mucosa Bucal/metabolismo , Mucosa Bucal/patologia , Ratos , Ratos Endogâmicos F344 , Estômago/efeitos dos fármacos , Estômago/patologia , Fatores de Tempo , Testes de Toxicidade , Compostos de Vinila/administração & dosagem , Abastecimento de Água
12.
FEBS Lett ; 507(3): 288-94, 2001 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-11696357

RESUMO

Glycogen synthase kinase 3 (GSK-3) has previously been shown to play an important role in the regulation of apoptosis. However, the nature of GSK-3 effector pathways that are relevant to neuroprotection remains poorly defined. Here, we have compared neuroprotection resulting from modulation of GSK-3 activity in PC12 cells using either selective small molecule ATP-competitive GSK-3 inhibitors (SB-216763 and SB-415286), or adenovirus overexpressing frequently rearranged in advanced T-cell lymphomas 1 (FRAT1), a protein proposed as a negative regulator of GSK-3 activity towards Axin and beta-catenin. Our data demonstrate that cellular overexpression of FRAT1 is sufficient to confer neuroprotection and correlates with inhibition of GSK-3 activity towards Tau and beta-catenin, but not modulation of glycogen synthase (GS) activity. By comparison, treatment with SB-216763 and SB-415286 proved more potent in terms of neuroprotection, and correlated with inhibition of GSK-3 activity towards GS in addition to Tau and beta-catenin.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Proteínas de Transporte , Proteínas do Citoesqueleto/metabolismo , Proteínas de Neoplasias , Proteínas Proto-Oncogênicas/metabolismo , Transativadores , Proteínas tau/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Adenoviridae/genética , Aminofenóis/farmacologia , Animais , Proteínas Quinases Dependentes de Cálcio-Calmodulina/antagonistas & inibidores , Citoplasma/metabolismo , Inibidores Enzimáticos/farmacologia , Regulação da Expressão Gênica , Quinase 3 da Glicogênio Sintase , Quinases da Glicogênio Sintase , Indóis/farmacologia , Maleimidas/farmacologia , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores , Células PC12 , Proteínas Proto-Oncogênicas/genética , Ratos , beta Catenina
13.
Nat Rev Mol Cell Biol ; 2(10): 769-76, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11584304

RESUMO

Glycogen synthase kinase 3 (GSK3) was initially described as a key enzyme involved in glycogen metabolism, but is now known to regulate a diverse array of cell functions. The study of the substrate specificity and regulation of GSK3 activity has been important in the quest for therapeutic intervention.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Animais , Proteínas Quinases Dependentes de Cálcio-Calmodulina/antagonistas & inibidores , Diabetes Mellitus Tipo 2/fisiopatologia , Drosophila melanogaster/embriologia , Embrião não Mamífero/fisiologia , Inibidores Enzimáticos/farmacologia , Glicogênio/biossíntese , Quinases da Glicogênio Sintase , Humanos , Insulina/fisiologia , Fosforilação , Biossíntese de Proteínas , Transdução de Sinais , Especificidade por Substrato
14.
Biochem J ; 359(Pt 1): 1-16, 2001 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-11563964

RESUMO

Identified originally as a regulator of glycogen metabolism, glycogen synthase kinase-3 (GSK3) is now a well-established component of the Wnt signalling pathway, which is essential for setting up the entire body pattern during embryonic development. It may also play important roles in protein synthesis, cell proliferation, cell differentiation, microtubule dynamics and cell motility by phosphorylating initiation factors, components of the cell-division cycle, transcription factors and proteins involved in microtubule function and cell adhesion. Generation of the mouse knockout of GSK3beta, as well as studies in neurons, also suggest an important role in apoptosis. The substrate specificity of GSK3 is unusual in that efficient phosphorylation of many of its substrates requires the presence of another phosphorylated residue optimally located four amino acids C-terminal to the site of GSK3 phosphorylation. Recent experiments, including the elucidation of its three-dimensional structure, have enhanced our understanding of the molecular basis for the unique substrate specificity of GSK3. Insulin and growth factors inhibit GSK3 by triggering its phosphorylation, turning the N-terminus into a pseudosubstrate inhibitor that competes for binding with the 'priming phosphate' of substrates. In contrast, Wnt proteins inhibit GSK3 in a completely different way, by disrupting a multiprotein complex comprising GSK3 and its substrates in the Wnt signalling pathway, which do not appear to require a 'priming phosphate'. These latest findings have generated an enormous amount of interest in the development of drugs that inhibit GSK3 and which may have therapeutic potential for the treatment of diabetes, stroke and Alzheimer's disease.


Assuntos
Quinase 3 da Glicogênio Sintase , Animais , Quinase 3 da Glicogênio Sintase/fisiologia , Humanos
15.
Mol Cell ; 7(6): 1321-7, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11430833

RESUMO

The inhibition of GSK3 is required for the stimulation of glycogen and protein synthesis by insulin and the specification of cell fate during development. Here, we demonstrate that the insulin-induced inhibition of GSK3 and its unique substrate specificity are explained by the existence of a phosphate binding site in which Arg-96 is critical. Thus, mutation of Arg-96 abolishes the phosphorylation of "primed" glycogen synthase as well as inhibition by PKB-mediated phosphorylation of Ser-9. Hence, the phosphorylated N terminus acts as a pseudosubstrate, occupying the same phosphate binding site used by primed substrates. Significantly, this mutation does not affect phosphorylation of "nonprimed" substrates in the Wnt-signaling pathway (Axin and beta-catenin), suggesting new approaches to design more selective GSK3 inhibitors for the treatment of diabetes.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/química , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Fosfatos/metabolismo , Proteínas Repressoras , Transativadores , Sequência de Aminoácidos , Arginina/metabolismo , Proteína Axina , Sítios de Ligação/fisiologia , Proteínas Quinases Dependentes de Cálcio-Calmodulina/genética , Linhagem Celular , Proteínas do Citoesqueleto/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Quinase 3 da Glicogênio Sintase , Humanos , Leucina/genética , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Fosforilação , Estrutura Terciária de Proteína , Proteínas/metabolismo , Serina/metabolismo , Especificidade por Substrato , beta Catenina
16.
J Trauma ; 50(4): 589-95; discussion 595-6, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11318005

RESUMO

BACKGROUND: Inhaled nitric oxide (INO) and prone positioning have both been advocated as methods to improve oxygenation in patients with acute respiratory distress syndrome (ARDS). This study was designed to evaluate the relative contributions of INO and prone positioning alone and in combination on gas exchange in trauma patients with ARDS. METHODS: Sixteen patients meeting the consensus definition of ARDS were studied. Patients received mechanical ventilation in the supine position, mechanical ventilation plus INO at 1 part per million in the supine position, mechanical ventilation in the PP, and mechanical ventilation in the prone positioning plus INO at 1 part per million. A stabilization period of 1 hour was allowed at each condition. After stabilization,hemodynamic and gas exchange variables were measured. RESULTS: INO and prone positioning both increased PaO2/FIO2 compared with ventilation in the supine position. PaO2/FIO2 increased by 14% during use of INO, and 10 of 16 patients (62%) responded to INO in the supine position. PaO2/FIO2 increased by 33%, and 14 of 16 patients (87.5%) responded to the prone position. The combination of INO and prone positioning resulted in an improvement in PaO2/FIO2 in 15 of 16 patients(94%), with a mean increase in PaO2/FIO2 of 59%. Pulmonary vascular resistance was reduced during use of INO, with a greater reduction in pulmonary vascular resistance seen with INO plus prone positioning (175 +/- 36 dynes x s/cm5 vs. 134 +/- 28 dynes x s/cm5) compared with INO in the supine position (164 +/- 48 dynes x s/cm5 vs.138 +/- 44 dynes x s/cm5). There were no significant hemodynamic effects of INO or prone positioning and no complications were seen during this relative short duration of study. CONCLUSIONS: INO and prone positioning can contribute to improved oxygenation in patients with ARDS. The two therapies in combination are synergistic and may be important adjuncts to mechanical ventilation in the ARDS patient with refractory hypoxemia.


Assuntos
Broncodilatadores/administração & dosagem , Óxido Nítrico/administração & dosagem , Decúbito Ventral , Síndrome do Desconforto Respiratório/terapia , Administração por Inalação , Adulto , Idoso , Gasometria , Terapia Combinada , Feminino , Hemodinâmica/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Traumatismo Múltiplo/complicações , Oxigênio/sangue , Respiração com Pressão Positiva/métodos , Estudos Prospectivos , Circulação Pulmonar/efeitos dos fármacos , Troca Gasosa Pulmonar/efeitos dos fármacos , Pressão Propulsora Pulmonar/efeitos dos fármacos , Síndrome do Desconforto Respiratório/etiologia , Síndrome do Desconforto Respiratório/metabolismo , Síndrome do Desconforto Respiratório/mortalidade , Síndrome do Desconforto Respiratório/fisiopatologia , Decúbito Dorsal , Análise de Sobrevida , Resultado do Tratamento , Resistência Vascular/efeitos dos fármacos
17.
Crit Care ; 5(2): 81-7, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11299066

RESUMO

BACKGROUND: Routine turning of critically ill patients is a standard of care. In recent years, specialized beds that provide automated turning have been introduced. These beds have been reported to improve lung function, reduce hospital-acquired pneumonia, and facilitate secretion removal. This trial was designed to measure the physiological effects of routine turning and respiratory therapy in comparison with continuous lateral rotation (CLR). METHODS: The study was a prospective, quasi-experimental, random assignment, trial with patients serving as their own controls. Paralyzed, sedated patients with acute respiratory distress syndrome were eligible for study. Patients were randomized to receive four turning and secretion management regimens in random sequence for 6 h each over a period of 24 h: (1) routine turning every 2 h from the left to right lateral position; (2) routine turning every 2 h from the left to right lateral position including a 15-min period of manual percussion and postural drainage (P&PD); (3) CLR with a specialized bed that turned patients from left to right lateral position, pausing at each position for 2 min; and (4) CLR with a specialized bed that turned patients from left to right lateral position pausing at each position for 2 min, and a 15-min period of percussion provided by the pneumatic cushions of the bed every 2 h. RESULTS: Nineteen patients were entered into the study. There were no statistically significant differences in the measured cardiorespiratory variables. There was a tendency for the ratio of partial pressure of arterial oxygen to fractional inspired oxygen concentration (PaO2/FIO2) to increase (174 +/- 31 versus 188 +/- 36; P = 0.068) and for the ratio of deadspace to tidal volume (Vd/Vt) to decrease (0.62 +/- 0.18 versus 0.59 +/- 0.18; P = 0.19) during periods of CLR, but these differences did not achieve statistical significance. There were statistically significant increases in sputum volume during the periods of CLR. The addition of P&PD did not increase sputum volume for the group as a whole. However, in the four patients producing more than 40 ml of sputum per day, P&PD increased sputum volume significantly. The number of patient turns increased from one every 2 h to one every 10 min during CLR. CONCLUSION: The acute effects of CLR are undoubtedly different in other patient populations (spinal cord injury and unilateral lung injury). The link between acute physiological changes and improved outcomes associated with CLR remain to be determined.


Assuntos
Cuidados Críticos/métodos , Paralisia/complicações , Respiração com Pressão Positiva , Postura , Síndrome do Desconforto Respiratório/terapia , Adulto , Idoso , Automação , Leitos , Cuidados Críticos/normas , Feminino , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica , Estudos Prospectivos , Síndrome do Desconforto Respiratório/complicações , Síndrome do Desconforto Respiratório/fisiopatologia , Sucção
18.
Toxicol Sci ; 60(1): 44-55, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11222872

RESUMO

Wyeth-14,643 (WY) and ammonium perfluorooctanoate (C8) belong to a diverse class of compounds which have been shown to produce hepatic peroxisome proliferation in rodents. From previous work, WY, but not C8, has been shown to produce hepatocellular carcinoma in rats, while C8 has been shown to produce Leydig cell adenomas. In addition, based on a review of bioassay data a relationship appears to exist between peroxisome-proliferating compounds and Leydig cell adenoma and pancreatic acinar cell hyperplasia/adenocarcinoma formation. To further investigate the relationship between peroxisome-proliferating compounds and hepatic, Leydig cell, and pancreatic acinar cell tumorigenesis, a 2-year feeding study in male CD rats was initiated to test the hypothesis that peroxisome proliferating compounds induce a tumor triad (liver, Leydig cell, pancreatic acinar cell), and to examine the potential mechanism for the Leydig cell tumors. The study was conducted using 50 ppm WY and 300 ppm C8. The concentration of WY in the diet was decreased to 25 ppm on test day 301 due to increased mortality. In addition to the ad libitum control, a second control was pair-fed to the C8 group. Interim sacrifices were performed at 1- or 3-month intervals. Peroxisome proliferation measured by beta-oxidation activity and cell proliferation were measured in the liver and testis at all time points and in the pancreas beginning at the 9-month time point (cell proliferation only). Serum hormone concentrations (estradiol, testosterone, LH, FSH, and prolactin) were also measured at each time point. Increased relative liver weights and hepatic beta-oxidation activity were observed in both the WY- and C8-treated rats at all time points. In contrast, hepatic cell proliferation was significantly increased only in the WY-treated group. Neither WY nor C8 significantly altered the rate of Leydig cell beta-oxidation or Leydig cell proliferation when compared to the control groups. Moreover, the basal rate of beta-oxidation in Leydig cells was approximately 20 times less than the rate of hepatic beta-oxidation. There were no biologically meaningful differences in serum testosterone, FSH, prolactin, or LH concentrations in the WY- and C8-treated rats when compared to their respective controls. There were, however, significant increases in serum estradiol concentrations in the WY- and C8-treated rats at 1, 3, 6, 9, 15, 18, and 21 months. At 12 months, only the C8-treated rats had elevated serum estradiol concentrations when compared to the pair-fed control. Histopathological evaluation revealed compound-related increases in liver, Leydig cell, and pancreatic acinar cell tumors in both WY- and C8-treated rats. The data support the hypothesis that the peroxisome-proliferating compounds induce the previously described tumor triad. In addition, both C8 and WY produced a sustained increase in serum estradiol concentrations that correlated with the potency of the 2 compounds to induce Leydig cell tumors (i.e., WY caused a more consistent sustained increase in serum estradiol throughout the entire study, and more specifically at the end of the study, than did C8). This study suggests that estradiol may play a role in enhancement of Leydig cell tumors in the rat, and that peroxisome proliferators may induce tumors via a non-LH type mechanism.


Assuntos
Caprilatos/toxicidade , Carcinógenos/toxicidade , Fluorocarbonos/toxicidade , Neoplasias Experimentais/induzido quimicamente , Proliferadores de Peroxissomos/toxicidade , Pirimidinas/toxicidade , Adenocarcinoma/induzido quimicamente , Adenocarcinoma/patologia , Animais , Testes de Carcinogenicidade , Divisão Celular/efeitos dos fármacos , Dieta , Estradiol/sangue , Hormônio Foliculoestimulante/sangue , Tumor de Células de Leydig/induzido quimicamente , Tumor de Células de Leydig/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/patologia , Longevidade/efeitos dos fármacos , Hormônio Luteinizante/sangue , Neoplasias Experimentais/sangue , Neoplasias Experimentais/patologia , Tamanho do Órgão/efeitos dos fármacos , Neoplasias Pancreáticas/induzido quimicamente , Neoplasias Pancreáticas/patologia , Prolactina/sangue , Ratos , Ratos Endogâmicos , Testosterona/sangue
19.
Lancet ; 356(9242): 1632-7, 2000 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-11089821

RESUMO

BACKGROUND: We assessed the effect of the introduction of laparoscopic cholecystectomy on surgical outcomes in routine practice. METHODS: Hospital discharge and death-certificate data were linked for all patients undergoing cholecystectomy (n=85120) in Scottish public-sector hospitals (n=51) between January, 1981, and June, 1999. The primary endpoints were cholecystectomy rate, hospital stay, and postoperative mortality. Regression methods were used to examine the effect of laparoscopic experience and surgeon caseload on postoperative mortality and hospital stay. FINDINGS: From 1989 to 1999, the proportion of cholecystectomies done laparoscopically rose from none to 80%, and the age-standardised cholecystectomy rate increased by 20% (95% CI 15-26). Postoperative mortality did not change in the 1990s (odds ratio 0.99 [0.7-1.4], p=0.99). The mean postoperative hospital stay fell from 8.0 (SD 3.7) to 2.9 (3.2) days. There was wide variation between hospitals in the proportion of cholecystectomies done laparoscopically and in average hospital stay. For individual surgeons, increasing laparoscopic experience and annual caseload were associated with higher proportions of laparoscopic procedures and shorter hospital stays. Postoperative mortality was higher during the first ten laparoscopic cholecystectomies done by a surgeon (compared with >200 procedures, odds ratio 2.3 [1.2-4.6], p=0.015). INTERPRETATION: The laparoscopic method reduced hospital stay but had no overall effect on postoperative mortality. Studies to assess the appropriateness of the increased cholecystectomy rate are merited. The wide variation in the proportion done laparoscopically, together with evidence of better results for surgeons doing more procedures, suggests scope for further reductions in hospital stay and morbidity.


Assuntos
Colecistectomia Laparoscópica/estatística & dados numéricos , Adulto , Idoso , Colecistectomia/estatística & dados numéricos , Colecistectomia Laparoscópica/mortalidade , Bases de Dados Factuais , Feminino , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Registro Médico Coordenado , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Período Pós-Operatório , Escócia/epidemiologia , Taxa de Sobrevida
20.
Surgery ; 128(4): 631-40, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11015097

RESUMO

BACKGROUND: The identification of trauma patients at risk for the development of deep venous thrombosis (DVT) at the time of admission remains difficult. The purpose of this study is to validate the risk assessment profile (RAP) score to stratify patients for DVT prophylaxis. METHODS: All patients admitted from November 1998 thru May 1999 were evaluated for enrollment. We prospectively assigned patients as low risk or high risk for DVT using the RAP score. High-risk patients received both pharmacologic and mechanical prophylaxis. Low-risk patients received none. Surveillance duplex Doppler scans were performed each week of hospitalization or if symptoms developed. Hospital charges for prophylaxis were used to determine the savings in the low-risk group. Statistical differences between the risk groups for each factor of the RAP and development of DVT were determined by the chi-squared test, with significance at a probability value of less than .05. RESULTS: There were 102 high-risk (64%) and 58 low-risk (36%) individuals studied. Eleven of the high-risk group (10.8%) experienced the development of DVT (asymptomatic, 64%). None of the low-risk group was diagnosed with DVT. Five of the 16 RAP factors were statistically significant for DVT. Eliminating prophylaxis and Doppler scans in low-risk patients resulted in a total savings of $18,908 in hospital charges. CONCLUSIONS: The RAP score correctly identified trauma patients at increased risk for the development of DVT. Despite prophylaxis, the high-risk group warrants surveillance scans. Withholding prophylaxis in low-risk patients can reduce hospital charges without risk.


Assuntos
Traumatismo Múltiplo/mortalidade , Medição de Risco/métodos , Trombose Venosa/mortalidade , Adulto , Idoso , Algoritmos , Anticoagulantes/uso terapêutico , Redução de Custos , Heparina/uso terapêutico , Custos Hospitalares , Humanos , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Estudos Prospectivos , Medição de Risco/economia , Fatores de Risco , Ultrassonografia Doppler Dupla/economia , Trombose Venosa/diagnóstico por imagem , Trombose Venosa/tratamento farmacológico
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