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2.
Lung Cancer ; 129: 22-27, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30797487

RESUMO

OBJECTIVES: There has been evidence of an association between patient outcomes and the number of surgeries performed at a hospital. To our knowledge, there are no Australian data on hospital cancer surgery volumes and patient outcomes. We evaluated the relationship between hospital non-small cell lung cancer (NSCLC) surgery volume and patient outcomes in Victoria. MATERIALS AND METHODS: Patients with a primary diagnosis of NSCLC between 2008 and 2014 were identified in the Victorian Cancer Registry (n = 15,369), 3,420 (22%) of whom had lung cancer surgery. Primary outcome was death within 90 days of surgery and secondary outcomes included overall survival, use of postoperative ventilation and ≥24hours spent in ICU. Hospital volume was measured as the average number of lung surgeries performed per year, with quartiles Q1: 1-17, Q2: 18-34, Q3: 35-58 and Q4: 59 + . RESULTS: 57% (1,941/3,420) lung cancer patients underwent lobectomy, 38% (1,299/3,420) sub-lobar resection and 5% (180/3,420) pneumonectomy. The overall 90-day mortality after lung surgery was 3.5%, and was 2.6% and 4.5% for patients undergoing lobectomy and sub-lobar resection respectively. There was no difference in 90-day mortality and overall survival between low- and high-volume centres regardless of procedure. Patients operated on in lower volume centres had more admissions to ICU ≥24hours (Q1. 55% vs. Q4. 11%, p-trend <0.001). A higher proportion of patients attending private hospitals (19%) had an ASA score of 4 compared with patients attending a public hospital (9%). CONCLUSION: We observed no evidence of survival differences between lung cancer patients attending low- and high-volume hospitals for cancer surgery. A higher proportion of patients had an ICU admission ≥24hours in lower volume centres and there are a higher proportion of patients with an ASA score of 4 in private hospitals compared to public hospitals.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/epidemiologia , Hospitais com Alto Volume de Atendimentos , Neoplasias Pulmonares/epidemiologia , Pneumonectomia/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Austrália/epidemiologia , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Feminino , Hospitalização , Humanos , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida , Resultado do Tratamento
3.
Int J Lab Hematol ; 39(1): 95-100, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27997764

RESUMO

INTRODUCTION: Hemoglobin (Hb) concentration is often measured in global health and nutrition surveys to determine anemia prevalence using a portable hemoglobinometer such as the Hemocue® Hb 201+. More recently, a newer model was released (Hemocue Hb 301) utilizing slightly different methods to measure Hb as compared to the older model. The objective was to measure bias and concordance between Hb concentrations using the Hemocue Hb 301 and Hb 201+ models in a rural field setting. METHODS: Hemoglobin (Hb) concentration was measured using one finger prick of blood (approximately 10 µL) from 175 Cambodian women (18-49 years) using three Hemocue Hb 201+ and three Hb 301 machines. Bias and concordance were measured and plotted. RESULTS: Overall, mean ± SD Hb concentration was 116 ± 13 g/L using the Hb 201+ and 118 ± 12 g/L using the Hb 301; and anemia prevalence (Hb < 120 g/L) was 58% (n = 102) and 58% (n = 101), respectively. Overall bias ± SD was 2.0 ± 10.5 g/L and concordance (95% CI) was 0.63 (0.54, 0.72). Despite the 2 g/L bias detected between models, anemia prevalence was very similar in both models. CONCLUSIONS: The two models measured anemia prevalence comparably in this population of women in rural Cambodia.


Assuntos
Anemia/sangue , Hemoglobinas/metabolismo , Anemia/epidemiologia , Camboja/epidemiologia , Feminino , Hemoglobinometria/instrumentação , Humanos , Prevalência
4.
Intern Med J ; 46(8): 964-9, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27553996

RESUMO

These guidelines, informed by the best available evidence and consensus expert opinion, provide a framework to guide the timely initiation of chemotherapy for treating cancer. They sit at the intersection of patient experience, state-of-the-art disease management and rational efficient service provision for these patients at a system level. Internationally, cancer waiting times are routinely measured and publicly reported. In Australia, there are existing policies and guidelines relating to the timeliness of cancer care for surgery and radiation therapy; however, until now, equivalent guidance for chemotherapy was lacking. Timeliness of care should be informed, where available, by evidence for improved patient outcomes. Independent of this, it should be recognised that shorter waiting periods are likely to reduce patient anxiety. While these guidelines were developed as part of a proposed framework for consideration by the Victorian Department of Health, they are clinically relevant to national and international cancer services. They are intended to be used by clinical and administrative staff within cancer services. Adoption of these guidelines, which are for the timely triage, review and treatment of cancer patients receiving systemic chemotherapy, aims to ensure that patients receive care within a timeframe that will maximise health outcomes, and that access to care is consistent and equitable across cancer services. Local monitoring of performance against this guideline will enable cancer service providers to manage proactively future service demand.


Assuntos
Tratamento Farmacológico/métodos , Hematologia , Oncologia , Neoplasias/tratamento farmacológico , Tempo para o Tratamento , Austrália , Gerenciamento Clínico , Humanos , Guias de Prática Clínica como Assunto , Indicadores de Qualidade em Assistência à Saúde
5.
J Perinatol ; 36(10): 897-900, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27253894

RESUMO

OBJECTIVE: Premature infants often receive pasteurized donor human milk when mothers are unable to provide their own milk. This study aims to establish the effect of the pasteurization process on a range of trace elements in donor milk. STUDY DESIGN: Breast milk was collected from 16 mothers donating to the milk bank at the Royal Brisbane and Women's Hospital. Samples were divided into pre- and post-pasteurization aliquots and were Holder pasteurized. Inductively coupled plasma mass spectrometry was used to analyze the trace elements zinc (Zn), copper (Cu), selenium (Se), manganese (Mn), iodine (I), iron (Fe), molybdenum (Mo) and bromine (Br). Differences in trace elements pre- and post-pasteurization were analyzed. RESULTS: No significant differences were found between the trace elements tested pre- and post-pasteurization, except for Fe (P<0.05). The median (interquartile range, 25 to 75%; µg l(-1)) of trace elements for pre- and post- pasteurization aliquots were-Zn: 1639 (888-4508), 1743 (878-4143), Cu: 360 (258-571), 367 (253-531), Se: 12.34 (11.73-17.60), 12.62 (11.94-16.64), Mn: (1.48 (1.01-1.75), 1.49 (1.11-1.75), I (153 (94-189), 158 (93-183), Fe (211 (171-277), 194 (153-253), Mo (1.46 (0.37-2.99), 1.42 (0.29-3.73) and Br (1066 (834-1443), 989 (902-1396). CONCLUSIONS: Pasteurization had minimal effect on several trace elements in donor breast milk but high levels of inter-donor variability of trace elements were observed. The observed decrease in the iron content of pasteurized donor milk is, however, unlikely to be clinically relevant.


Assuntos
Leite Humano/química , Pasteurização , Oligoelementos/análise , Feminino , Humanos , Lactente , Fenômenos Fisiológicos da Nutrição do Lactente , Recém-Nascido Prematuro , Espectrometria de Massas , Bancos de Leite Humano
6.
Diabet Med ; 31(6): 691-8, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24344757

RESUMO

AIMS: To examine how fasting glucose and glucose tolerance are related to magnetic resonance imaging-assessed indicators of subclinical cerebrovascular disease and brain atrophy and their variation according to age, sex and education. METHODS: Participants in the present study were 172 healthy, community-dwelling older adults. An oral glucose tolerance test was administered and magnetic resonance imaging performed. Fasting, 2-h, and 2-h area-under-the-curve glucose levels, their associations with subclinical cerebrovascular disease and brain atrophy, and their respective interactions with age, sex and education were examined. RESULTS: A positive association between fasting glucose and subclinical cerebrovascular disease (but not brain atrophy) emerged; this association was more pronounced for participants with < 12 years of education; however, glucose tolerance was not related to subclinical cerebrovascular disease or brain atrophy. CONCLUSIONS: Findings revealed a potential link between fasting glucose levels and the presence of subclinical cerebrovascular disease indicators - white matter hyperintensities and silent brain infarction - in older adults without diabetes and with an education level below high school. Additional research is needed to confirm these associations and to determine the need for interventions aimed at closely monitoring and preventing elevated glucose levels in this population to reduce the prevalence of subclinical cerebrovascular disease.


Assuntos
Glicemia/metabolismo , Encéfalo/patologia , Transtornos Cerebrovasculares/patologia , Diabetes Mellitus Tipo 2/patologia , Angiopatias Diabéticas/patologia , Nefropatias Diabéticas/patologia , Idoso , Idoso de 80 Anos ou mais , Atrofia/sangue , Atrofia/patologia , Transtornos Cerebrovasculares/sangue , Estudos Transversais , Diabetes Mellitus Tipo 2/sangue , Angiopatias Diabéticas/sangue , Nefropatias Diabéticas/sangue , Jejum/sangue , Feminino , Teste de Tolerância a Glucose , Voluntários Saudáveis , Humanos , Angiografia por Ressonância Magnética , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
7.
BMJ Open ; 3(7)2013.
Artigo em Inglês | MEDLINE | ID: mdl-23847268

RESUMO

OBJECTIVES: Current evidence to support non-medical prescribing is predominantly qualitative, with little evaluation of accuracy, safety and appropriateness. Our aim was to evaluate a new model of service for the Australia healthcare system, of inpatient medication prescribing by a pharmacist in an elective surgery preadmission clinic (PAC) against usual care, using an endorsed performance framework. DESIGN: Single centre, randomised controlled, two-arm trial. SETTING: Elective surgery PAC in a Brisbane-based tertiary hospital. PARTICIPANTS: 400 adults scheduled for elective surgery were randomised to intervention or control. INTERVENTION: A pharmacist generated the inpatient medication chart to reflect the patient's regular medication, made a plan for medication perioperatively and prescribed venous thromboembolism (VTE) prophylaxis. In the control arm, the medication chart was generated by the Resident Medical Officers. OUTCOME MEASURES: Primary outcome was frequency of omissions and prescribing errors when compared against the medication history. The clinical significance of omissions was also analysed. Secondary outcome was appropriateness of VTE prophylaxis prescribing. RESULTS: There were significantly less unintended omissions of medications: 11 of 887 (1.2%) intervention orders compared with 383 of 1217 (31.5%) control (p<0.001). There were significantly less prescribing errors involving selection of drug, dose or frequency: 2 in 857 (0.2%) intervention orders compared with 51 in 807 (6.3%) control (p<0.001). Orders with at least one component of the prescription missing, incorrect or unclear occurred in 208 of 904 (23%) intervention orders and 445 of 1034 (43%) controls (p<0.001). VTE prophylaxis on admission to the ward was appropriate in 93% of intervention patients and 90% controls (p=0.29). CONCLUSIONS: Medication charts in the intervention arm contained fewer clinically significant omissions, and prescribing errors, when compared with controls. There was no difference in appropriateness of VTE prophylaxis on admission between the two groups. TRIAL REGISTRATION: Registered with ANZCTR-ACTR Number ACTRN12609000426280.

11.
J Epidemiol Community Health ; 63(7): 541-5, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19282315

RESUMO

BACKGROUND: Impaired lung function is independently associated with higher rates of disability; however, few studies have examined the extent to which this relationship varies by sex. Because men are less likely to have disability, it is expected that the relationship between lung function and disability will be greater among women. METHODS: Logistic regression models were specified to examine the relationship between lung function and disability in 689 African-American men and women participating in the Carolina African American Twin Study of Aging. Disability was defined as difficulty in performing at least one of seven basic activities of daily living. Impaired lung function was defined as per cent of predicted peak expiratory flow (PEF) <80. RESULTS: Accounting for demographic and health-related characteristics, women who had impaired lung function had a higher odds (OR 1.77; 95% CI 1.02 to 3.06) of being disabled than those with normal lung function. Impaired lung function was unrelated to disability in men. CONCLUSION: Lung function appears to vary by sex in this sample of African-Americans. Furthermore, among women, lung function should be considered as an important indicator of health. Every effort should be made to improve lung function in African-Americans, but interventions and health promoting strategies may need to be sex specific.


Assuntos
Negro ou Afro-Americano , Pessoas com Deficiência/estatística & dados numéricos , Complacência Pulmonar/fisiologia , Pico do Fluxo Expiratório/fisiologia , Atividades Cotidianas , Adulto , Estudos Transversais , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , North Carolina/epidemiologia , Fatores de Risco , Fatores Sexuais
12.
Int J Obes (Lond) ; 30(2): 243-50, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16189498

RESUMO

OBJECTIVE: African Americans have a particularly high prevalence of excessive body fat and high blood pressure. Genetic and environmental influences may be implicated for both of these risk factors. We investigated the potential for common genetic and environmental influences on body fat (waist circumference (WC), body mass index (BMI)) and blood pressure measures (systolic and diastolic pressure (SBP, DBP)) among African-American male and female subjects. RESEARCH METHODS AND PROCEDURES: Measurements were taken as part of the Carolina African-American Twin Study of Aging (CAATSA). The CAATSA sample contains 217 same-sex African-American male and female twins with average age of 47 years. This analysis included 39 monozygotic male pairs (MZ), 43 dizygotic male pairs (DZ); 63 MZ female pairs, and 72 DZ female pairs. Maximum likelihood quantitative genetic analyses were used. RESULTS: The total genetic variance for SBP was 22% in male subjects and 40.1% in female subjects. Of this total variance, 3.1% was in common with BMI in male subjects and 6% was in common with BMI in female subjects. After controlling for the effects of BMI, WC had less than 1% of its variance in common with SBP in male and female subjects. For DBP, the total genetic variance was 16.9% in male and 38.7% in female subjects. Of this total variance 6.1% was in common with BMI in male subjects and 3.7% was in common in female subjects. Again, WC had less than 1% of its genetic variance in common with DBP in both male and female subjects. The environmental variance common among these measures was also very small. The remaining variance was primarily accounted for by genetic and environmental effects unique to each measure as well as age. DISCUSSION: Based on the very small common genetic variance for BMI, SBP, and DBP as well as WC and the blood pressure measures, our results suggest that searching for common genes among these measures may be inconclusive.


Assuntos
Negro ou Afro-Americano/genética , Pressão Sanguínea/genética , Índice de Massa Corporal , Meio Ambiente , Gêmeos , Adulto , Composição Corporal , Diástole , Feminino , Humanos , Funções Verossimilhança , Masculino , Pessoa de Meia-Idade , Sístole , Gêmeos Dizigóticos , Gêmeos Monozigóticos
13.
J Paediatr Child Health ; 40(8): 466-9, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15265189

RESUMO

OBJECTIVE: Surveillance of patients presenting with acute flaccid paralysis (AFP) is the World Health Organization (WHO) recommended method for the detection of incident cases of poliovirus infection. Australia was certified free of circulating poliovirus in 2000 but is required to continue AFP surveillance until global certification. Although Australia reached the WHO nominated surveillance target in 2000 and 2001, it was not reached in 2002. Notification rates between states have been variable. We aim to investigate the difference in notification rates by state to determine whether different rates reflect different patterns of disease or different approaches to reporting. METHODS: Notification rates were reviewed by state for the years 1997-2002. The completeness of case ascertainment was reviewed from published studies. Key informants described differences in AFP reporting in states with consistent differences in notification rates. RESULTS: Australia achieved 75% of the WHO surveillance target for AFP cases between 1997 and 1999 and 98% between 2000 and 2002. After 2000, Queensland achieved 150% of its target while Victoria achieved less than 50%. New South Wales reached its target over the entire 6 years but other states and territories were not as consistent. Although the formal process for AFP reporting is uniform throughout Australia, many differences in approach were identified between Victoria and Queensland. CONCLUSION: Maintaining AFP surveillance at the required WHO standard will be more likely in Australia if the populous states are able to notify cases at the same rate as Queensland (since 2000) and New South Wales (in general).


Assuntos
Paraplegia , Notificação aos Pais , Doença Aguda , Austrália/epidemiologia , Diagnóstico Diferencial , Humanos , Incidência , Poliomielite/diagnóstico , Poliomielite/epidemiologia , Queensland/epidemiologia , Vitória/epidemiologia
14.
J Aging Health ; 12(1): 69-89, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10848126

RESUMO

OBJECTIVES: The purpose of the analyses was to examine the impact of health-related variables on race differences in neuropsychological functioning (Boston Naming Task). METHODS: Using cross-sectional data from the MacArthur Successful Aging Study, the authors examined the relationship of demographic characteristics, health status, health habits, physical functioning, and speed of performance to naming and incidental recall of items from the Boston Naming Task. Participants were 1,175 healthy African American and European American older persons 70 to 79 years old. RESULTS: Regression analyses indicated that although race differences persisted for confrontational naming after controlling for demographic and health factors, there was no effect due to race for incidental recall scores or for savings scores for recall. DISCUSSION: The racial differences found in test performance may reflect differences in cultural appropriateness of the material rather than differences in ability.


Assuntos
Envelhecimento , Memória , Testes Neuropsicológicos , Grupos Raciais , Negro ou Afro-Americano , Idoso , Cultura , Demografia , Nível de Saúde , Humanos , Estados Unidos , População Branca
15.
Exp Aging Res ; 25(3): 209-21, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10467512

RESUMO

Results from previous research on everyday problem solving involving Caucasians suggests that it may be a useful concept in studying cognitive aging in African Americans. The purpose of this investigation was to examine: (1) the factor structure of an everyday problem solving in a sample of African Americans, (2) the internal consistency of everyday-problem solving in a sample of African Americans, and (3) the relationship of problem solving to demographic factors, physical functioning, and measures of fluid ability. The sample included subjects recruited from Baltimore, MD. The sample consisted of 249 community dwelling African-American adults with a mean age of 67.8 years (SD = 8.47). Variables included the Everyday Problem Solving Test (EPT), gender, age, education, physical functioning, and inductive reasoning. Everyday problem solving as a latent construct was confirmed and the split half reliability was high (.89). As in previous research, inductive reasoning and physical functioning were related to everyday problem solving abilities. We also found that certain domains of the EPT are more influenced by demographic factors than others. Our finding suggest that the Everyday Problems Test is appropriate for use with African American samples.


Assuntos
Envelhecimento/psicologia , Negro ou Afro-Americano/psicologia , Resolução de Problemas , Adulto , Idoso , Idoso de 80 Anos ou mais , Cognição , Estudos de Avaliação como Assunto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Psicológicos
16.
Exp Aging Res ; 25(3): 255-65, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10467515

RESUMO

Previous research has shown that forced expiratory volume (FEV) is a useful predictor of remaining life in older adults. The present analyses are an attempt to replicate results from a study of Swedish twins which demonstrated substantial heritability of FEV with a sample of middle-aged Russian adult twins. Data were collected from 116 pairs of Russian twins (monozygote = 71, dizygotic = 45, mean age = 40.9 years). Phenotypic correlations between FEV, age, gender, height, and cigarette consumption (in pack years) were all significant, ranging from -.72 to .31. After the effects of age, gender, height, and smoking were partialled out of FEV, quantitative genetic analyses were conducted. Shared environmental effects were significant, accounting for 47% of the variance in FEV. Genetic effects, which accounted for about 28% of the variance, could be dropped from the model without a significant decrease in the fit. These results are discussed in relation to previous research conducted in other countries.


Assuntos
Envelhecimento/genética , Envelhecimento/fisiologia , Volume Expiratório Forçado/genética , Volume Expiratório Forçado/fisiologia , Adulto , Comparação Transcultural , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Federação Russa , Suécia , Gêmeos Dizigóticos , Gêmeos Monozigóticos
17.
J Gerontol B Psychol Sci Soc Sci ; 54(3): P173-9, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10363039

RESUMO

The relative importance of genetic and environmental influences on episodic memory in very late life was studied using a quantitative genetic approach. Identical (n = 125) and same-sex fraternal (n = 157) twin pairs, aged 80 and older (mean age = 83.3; SD = 3.1) and without a diagnosis of dementia were tested with seven memory measures: (1-2) Digit Span Forward and Backwards, (3) Prose Recall, (4) Thurstone's picture memory test, and the Memory in Reality (MIR) test, including the subtasks of (5) free recall, (6) recognition, and (7) relocation. Heritabilities, estimated by structural equation modeling, ranged from .04 to .49. The digit span backward test showed the highest heritability (h2 = .49), while heritabilities were typically lower for the long-term memory measures. The results demonstrate genetic influences on memory in the oldest-old, but suggest that the magnitude of these effects differs across memory measures.


Assuntos
Idoso de 80 Anos ou mais/psicologia , Envelhecimento/genética , Memória , Idoso , Envelhecimento/psicologia , Feminino , Humanos , Masculino , Gêmeos Dizigóticos
18.
Int J Aging Hum Dev ; 48(1): 73-9, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10363561

RESUMO

To fully understand the differences present between various ethnic and racial groups, there must be an understanding of the heterogeneity that is represented within a given ethnic/racial group. The purpose of this article is to discuss the importance of an individual differences approach in studying the ethnic diversity of an aging population. Conceptual, methodological, and design issues are discussed with the goal of better understanding the developmental processes of aging minority elderly populations.


Assuntos
Envelhecimento/etnologia , Comparação Transcultural , Grupos Minoritários , Projetos de Pesquisa , Idoso , Envelhecimento/psicologia , Diversidade Cultural , Humanos , Individualidade , Grupos Minoritários/psicologia , Estados Unidos
19.
Ethn Dis ; 7(2): 127-36, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9386953

RESUMO

Using cross-sectional and longitudinal data from the MacArthur Successful Aging Study, this paper examines associations between cognition and indices of health in 224 elderly African Americans 70 to 79 years of age at initial interview. The results indicated that greater average peak expiratory flow was predictive of better cognitive performance at the first interview. One longitudinal analysis showed that gender was the only significant predictor of change (change as a continuous variable) with women tending to slightly improve their cognitive performance over time. When change was treated as a dichotomous variable (e.g., a decline of 6 or more points), lower levels of average peak expiratory flow and education were predictive of decline, and positive self-ratings of current health and changes in health in the past year were important factors in the improvement of cognitive performance. The results indicate that, in addition to education, health is an important predictor of the status and course of cognitive functioning in older African Americans.


Assuntos
Envelhecimento , Negro ou Afro-Americano , Cognição , Indicadores Básicos de Saúde , Idoso , Estudos Transversais , Feminino , Humanos , Modelos Logísticos , Estudos Longitudinais , Masculino , Testes Neuropsicológicos
20.
J Membr Biol ; 147(2): 173-83, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8568853

RESUMO

We have used the patch clamp technique to study volume-activated Cl- currents in the bicarbonate-secreting pancreatic duct cell. These currents could be elicited by a hypertonic pipette solution (osmotic gradient 20 mOsm/l), developed over about 8 min to a peak value of 91 +/- 5.8 pA/pF at 60 mV (n = 123), and were inhibited by a hypertonic bath solution. The proportion of cells which developed currents increased from 15% in freshly isolated ducts to 93% if the ducts were cultured for 2 days. The currents were ATP-dependent, had an outwardly rectifying current/voltage (I-V) plot, and displayed time-dependent inactivation at depolarizing potentials. The anion selectivity sequence was: ClO4 = I = SCN > Br = NO3 > Cl > F > HCO3 > gluconate, and the currents were inhibited to a variable extent by DIDS, NPPB, dideoxyforskolin, tamoxifen, verapamil and quinine. Increasing the intracellular Ca2+ buffering capacity, or lowering the extracellular Ca2+ concentration, reduced the proportion of duct cells which developed currents. However, removal of extracellular Ca2+ once the currents had developed was without effect. Inhibiting protein kinase C (PKC) with either the pseudosubstrate PKC (19-36), calphostin C or staurosporine completely blocked development of the currents. We speculate that cell swelling causes Ca2+ influx which activates PKC which in turn either phosphorylates the Cl- channel or a regulatory protein leading to channel activation.


Assuntos
Cloretos/metabolismo , Ductos Pancreáticos/metabolismo , Ácido 4,4'-Di-Isotiocianoestilbeno-2,2'-Dissulfônico/farmacologia , Trifosfato de Adenosina/metabolismo , Animais , Ânions/farmacologia , Cálcio/metabolismo , Cálcio/farmacologia , Tamanho Celular , Canais de Cloreto/antagonistas & inibidores , Canais de Cloreto/efeitos dos fármacos , Canais de Cloreto/metabolismo , Técnicas In Vitro , Transporte de Íons , Potenciais da Membrana , Ductos Pancreáticos/citologia , Fosforilação , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/metabolismo , Ratos , Ratos Wistar
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