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91.
Structural and functional abnormalities in the islets isolated from type 2 diabetic subjects 总被引:15,自引:0,他引:15
Deng S Vatamaniuk M Huang X Doliba N Lian MM Frank A Velidedeoglu E Desai NM Koeberlein B Wolf B Barker CF Naji A Matschinsky FM Markmann JF 《Diabetes》2004,53(3):624-632
Type 2 diabetic subjects manifest both disordered insulin action and abnormalities in their pancreatic islet cells. Whether the latter represents a primary defect or is a consequence of the former is unknown. To examine the beta-cell mass and function of islets from type 2 diabetic patients directly, we isolated islets from pancreata of type 2 diabetic cadaveric donors (n = 14) and compared them with islets from normal donors (n = 14) matched for age, BMI, and cold ischemia time. The total recovered islet mass from type 2 diabetic pancreata was significantly less than that from nondiabetic control subjects (256,260 islet equivalents [2,588 IEq/g pancreas] versus 597,569 islet equivalents [6,037 IEq/g pancreas]). Type 2 diabetic islets were also noted to be smaller on average, and histologically, islets from diabetic patients contained a higher proportion of glucagon-producing alpha-cells. In vitro study of islet function from diabetic patients revealed an abnormal glucose-stimulated insulin release response in perifusion assays. In addition, in comparison with normal islets, an equivalent number of type 2 diabetic islets failed to reverse hyperglycemia when transplanted to immunodeficient diabetic mice. These results provide direct evidence for abnormalities in the islets of type 2 diabetic patients that may contribute to the pathogenesis of the disease. 相似文献
92.
To determine whether age of bottle-weaning is associated with overweight in young children, National Health and Nutrition Examination Survey III data for 3027 children aged 3-5 years were analyzed. The main outcome measure, the child's body mass index (BMI), was measured as: <85%, 85-95%, >95%. Mean bottle-weaning age was 18.78 months. After adjustment for potential confounders, each additional month of bottle use corresponded to a 3% increase in the odds of being in a higher BMI category (95% CI 0.0099-0.0535). Prolonged bottle use in young children is associated with increased risk of overweight. From a preventive medicine standpoint, decreasing exposure to this potential risk for childhood overweight is indicated. 相似文献
93.
Genetic variables are thought to interact with environmental factors, such as alcohol exposure history, to produce individual differences in alcohol abuse and alcoholism. The objective of this study was to test the potential interaction between genetic predisposition to consume alcohol and alcohol pretreatment on subsequent self-administration. To accomplish this goal, four groups of mice from the ethanol-avoiding DBA/2J (D2) and ethanol-preferring C57BL/6J (B6) inbred strains were exposed to saline, acute ethanol (2 g/kg), or chronic intermittent ethanol (1 or 2 g/kg) intraperitoneal (i.p.) injections. Locomotor activity was monitored after each injection. After preexposure, animals were given a two-bottle choice test with various concentrations of ethanol/sucrose vs. sucrose or ethanol vs. water for 4 days at each concentration. Then, all animals were challenged with a 2.0 g/kg ethanol i.p. injection and locomotor activity was assessed. Acute and chronic ethanol pretreatment increased locomotor activity in response to a challenge dose of ethanol (2 g/kg) in D2 mice but had no effect on B6 mice. Prior exposure to ethanol altered the amount of ethanol consumed in a mouse strain-dependent manner. D2 mice showed a positive relationship between ethanol intake and dose or duration of ethanol preexposure. B6 mice preexposed to ethanol consumed more ethanol than naive animals, independent of dose or duration of exposure. During the last phase of self-administration testing, D2 mice exposed to chronic ethanol (2 g/kg) consumed as much ethanol as B6 from the same pretreatment condition. After a history of ethanol self-administration, saline control mice from the D2 strain showed equal locomotor activation as compared to D2 mice that were pretreated with ethanol injections. B6 mice showed no change in locomotor activity after ethanol self-administration or injection. These results demonstrate that genetic predisposition to avoid alcohol (D2 mice) can be modified by a history of preexposure and that a predisposition to prefer alcohol (B6 mice) may be also amenable to influence by drug history. In general, the results of this study suggest that genetic factors may interact with previous exposure to ethanol to modify ethanol self-administration. 相似文献
94.
95.
Yancy CW Burnett JC Fonarow GC Silver MA 《Congestive heart failure (Greenwich, Conn.)》2004,10(5):230-236
Heart failure (HF) management has seen enormous advances in the past two decades, including publication of HF management guidelines targeted at further reduction of morbidity and mortality. Nonetheless, the morbidity of HF has steadily increased and now represents one of the largest health care expenditures in this country. Because hospitalization for HF is most likely for patients with more advanced HF, they share a disproportionate burden of the hospitalization costs and will require treatment regimens beyond the current guidelines, if this burden is to be alleviated. In June 2004, a group of investigators who helped establish the natriuretic peptide treatment paradigm, met to discuss the potential role of nesiritide as an outpatient treatment option for patients with symptomatic HF who were at high risk for repeated admissions, a syndrome now described as "chronic decompensated HF." This report presents their considerations on the contribution of natriuretic peptide physiology to the amelioration of progressive left ventricular dysfunction, the therapeutic use of B-type natriuretic peptide, and its potential application to the outpatient management of acute and chronic decompensated HF. The use of outpatient IV nesiritide was considered a promising treatment option for symptomatic chronic decompensated HF patients that merits further investigation. Such an approach, once validated, should be integrated into an evidence-based HF disease management program. 相似文献
96.
This paper reports the prediction of marijuana use cessation among young adults who were regular users 5 years earlier. Social, attitude, intrapersonal, violence-related, drug use, and demographic baseline measures served as predictors of whether or not 339 teenage marijuana users reported having quit use 5 years later. Young adult social role variables were included as additional predictors. Quitting was defined as having not used marijuana in the last 30 days (42% of the sample at follow-up). After controlling for covariation among predictors, in a three-step analysis, only baseline level of marijuana use, male gender, young adult marital status, and friends' marijuana use (marginal) remained statistically direct predictors. Implications of these results include the need to reduce psychological dependence on marijuana and increase social unacceptability of marijuana use across genders to help increase prevalence of quit attempts. 相似文献
97.
98.
Paradise JL Feldman HM Campbell TF Dollaghan CA Colborn DK Bernard BS Rockette HE Janosky JE Pitcairn DL Sabo DL Kurs-Lasky M Smith CG 《The Pediatric infectious disease journal》2003,22(4):309-314
BACKGROUND: Whether prompt insertion of tympanostomy tubes in children with persistent early life otitis media prevents or minimizes subsequent developmental impairment has been the subject of conflicting opinions and differing approaches to management. METHODS: We randomly assigned 429 children with persistent middle ear effusion (MEE) before the age of 3 years to have tympanostomy tubes inserted either as soon as possible or up to 9 months later if MEE persisted. In 402 of these children, we found no significant differences at age 3 years between the 2 treatment groups in mean scores on any measure of speech, language and cognition and in 401 of the children no significant differences in measures of psychosocial development. We then examined outcomes within subgroups of children who might have been the most severely affected, namely those who had been randomized on the basis of bilateral, continuous MEE rather than unilateral and/or discontinuous MEE and those who had the greatest degrees of hearing loss. RESULTS: In none of the subgroups we considered were scores on any outcome measure significantly more favorable in children in the early treatment group than in children in the late treatment group. CONCLUSIONS: In otherwise normal children who have MEE, during the first 3 years of life within the durations we studied, prompt insertion of tympanostomy tubes does not measurably improve developmental outcomes at age 3 years, irrespective of whether MEE has been continuous or discontinuous and unilateral or bilateral and whether or not MEE has been accompanied by mild to moderate hearing loss. 相似文献
99.
100.
Bruising is very common in children. Examination of bruising can guide the clinician in ordering radiographic imaging studies of children who have suffered trauma. Additionally, bruising in infants and patterns of bruising that do not match the injury scenario offered by caretakers can raise the suspicion of abuse. This article reports preliminary experience with Wood lamp enhancement of faint bruises and visualization of bruises that are not visible. It describes the method for digital photography of bruises visualized in this way. Finally, it suggests future applications and areas of further study. 相似文献