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141.
142.
Rajesh Garg Zhao Chen Thomas Beck Jane A. Cauley Guanglin Wu Dorothy Nelson Beth Lewis Andrea LaCroix Meryl S. LeBoff 《Metabolism: clinical and experimental》2012,61(12):1756-1762
ObjectiveWomen with type 2 diabetes mellitus (T2DM) have a higher risk of fractures despite increased bone mineral density (BMD) as compared to women without diabetes. We hypothesized that bone strength is diminished in women with T2DM after accounting for lean body mass, which may contribute to their increased fracture risk.MethodsParticipants from Women's Health Initiative Observational Study were included in this cross-sectional study. These analyses include 3 groups of women: 1) T2DM women on diet or oral hypoglycemic agents (n = 299); 2) T2DM women on insulin therapy (with or without oral agents) (n = 128); and 3) Non-diabetic control women (n = 5497). Hip structural analyses were done using the validated Beck's method on hip scans from dual energy x-ray absorptiometry (DXA). We compared BMD and section modulus (bending strength) at the narrow neck with and without correcting for total body DXA lean body mass.ResultsWomen in all three groups were of similar ages (63.7, 64.6 and 64.2 years, respectively) and heights, but those with T2DM were heavier, with greater lean body weight vs controls (P < .001). In both diabetic groups, absolute BMD and section modulus were higher compared with controls. However, after adjusting for total lean body weight, diabetic women on insulin had significantly lower BMD and section modulus.ConclusionAdjusted for lean body weight, the BMD and bending strength in the femoral neck are significantly lower in insulin-treated diabetic women vs controls. This may represent altered adaptation of bone modeling and explain the higher fracture risk in patients with T2DM. 相似文献
143.
Blencowe H Cousens S Oestergaard MZ Chou D Moller AB Narwal R Adler A Vera Garcia C Rohde S Say L Lawn JE 《Lancet》2012,379(9832):2162-2172
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Background: Ethanol (EtOH) consumption during pregnancy can lead to fetal growth retardation, mental retardation, and neurodevelopmental delay. The fetal brain initiates neurogenesis and vasculogenesis during the second trimester, and depends on maternal‐fetal circulation for nutrition and growth signals. We used high‐resolution in vivo ultrasound imaging to test the hypothesis that EtOH interferes with fetal brain‐directed blood flow during this critical developmental period. Methods: Pregnant mice were lightly anesthetized on gestational day 12 with an isoflurane/oxygen mixture. We assessed the effect of single and repeated binge‐like maternal EtOH exposures at 3 g/kg, administered by intragastric gavage or intraperitoneal injection, on maternal circulation and fetal umbilical, aortic, internal carotid, and middle cerebral arterial circulation. Results: Binge maternal EtOH exposure, regardless of exposure route, significantly reduced fetal arterial blood acceleration and velocity time integral (VTI), from umbilical to cerebral arteries, without a change in fetal heart rate and resistivity indices. Importantly a single maternal binge EtOH exposure induced persistent suppression of fetal arterial VTI for at least 24 hours. Repeated binge episodes resulted in a continuing and persistent suppression of fetal VTI. Qualitative assessments showed that maternal EtOH exposure induced oscillatory, nondirectional blood flow in fetal cerebral arteries. Maternal cardiac and other physiological parameters remained unaltered. Conclusions: These data show that binge‐type maternal EtOH exposure results in rapid and persistent loss of blood flow from the umbilical artery to the fetal brain, potentially compromising nutrition and the maternal/fetal endocrine environment during a critical period for neuron formation and angiogenesis in the maturing brain. 相似文献
146.
Marijuana is the most abused recreational drug in the United States. Cannabinoids, the active ingredients of marijuana, affect multiple organ systems in the human body. The pharmacologic effects of marijuana, based on stimulation of cannabinoid receptors CB1 and CB2, which are widely distributed in the cardiovascular system, have been well described. Activation of these receptors modulates the function of various cellular elements of the vessel wall, and may contribute to the pathogenesis of atherosclerosis. Clinically, there are reports linking marijuana smoking to the precipitation of angina and acute coronary syndromes. Recently, large published clinical trials with CB1 antagonist rimonabant did not show any significant benefit of this agent in preventing progression of atherosclerosis. In light of these findings and emerging data on multiple pathways linking cannabinoids to atherosclerosis, we discuss the literature on the role of cannabinoids in the pathophysiology of atherosclerosis. We also propose a marijuana paradox, which implies that inhalation of marijuana may be linked to precipitation of acute coronary syndromes, but modulation of the endocannabinoid system by a noninhalation route may have a salutary effect on the development of atherosclerosis. 相似文献
147.
Saliva plays a vital role in oral health as patients strive to maintain a healthy dentition throughout their lives. It is natures primary defense mechanism for the oral environment, and is particularly important for protecting exposed tooth surfaces. While internal protection for dentin comes from odontoblasts and the dental pulp, the body's external protection for enamel comes from saliva. The noninvasive nature of salivary testing has made it an effective alternative to blood and urine testing and home testing kits have made it possible for people to monitor their own health using this diagnostic medium. This paper presents what saliva can reveal about general and oral health as well as highlights the current use and potential clinical and research applications, of diagnostics based on oral fluids. CLINICAL SIGNIFICANCE: Early detection always minimizes the need for more invasive treatment. It prevents oral health disease at an early stage and provides a good oral health in rejuvenated state. If you stick and follow regular professional care, prevention maintenance appointments, prevention counseling, good home care and oral hygiene, diet habits you will be free from oral health illness and you can experience the harmonious and rejuvenated state of good oral health. 相似文献
148.
Sudhakara Reddy Lingam Amara Swapna Tatipudi Ramesh Takur Rajesh Singh Koppolu Pradeep 《Journal of investigative and clinical dentistry》2012,3(4):298-303
Aim: To determine the influence of smoking on the blood and salivary superoxide dismutase levels among smokers, and to demonstrate the significance in alterations in the levels of superoxide dismutase in association with patient age, periodontal disease status, and duration and smoking frequency. Methods: Sixty healthy male patients (aged 20–60 years) constituted the target population. Blood and saliva samples were collected, and the periodontal index was measured using a Community Periodontal Index probe. Blood and salivary superoxide dismutase levels were calculated with the reagents prepared, and values were measured in a UV spectrophotometer. Results: There was a significant decrease in mean superoxide dismutase levels with an increase in age and smoking duration and frequency (0.23–0.05 U/mL). There was a range of 0.31–0.06 U/mL variation in the mean superoxide dismutase levels as the periodontal disease condition deteriorated. Conclusions: There was a significant reduction in the superoxide dismutase levels in the blood and saliva of smokers with increased duration and frequency of smoking, and as the periodontal disease condition worsened. Thus, this study emphasizes the importance of saliva as an easy, non‐invasive procedure in the diagnosis of patients who are more prone to precancerous lesions and conditions, and its importance in patient education and motivation programs for smoking cessation. 相似文献
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There is paucity of literature on the relation of obesity with recurrent and chronic pancreatitis. We recorded the clinical details and the outcome of five patients with recurrent pancreatitis who had components of the metabolic syndrome. Their age ranged from 8 to 20 years. All five patients had acanthosis nigricans. Body mass index (BMI) could not be evaluated as these patients lost weight following episodes of pancreatitis. Three patients had two or more first-degree relatives who had diabetes mellitus. Only one patient had severe necrotizing pancreatitis. Coexisting liver disease was seen in two patients. Elevated serum cholesterol levels and moderately elevated serum triglycerides along with elevated serum amylase levels observed in these patients suggest possibility of a different mechanism from that of hypertriglyceridemia-related pancreatitis. Evaluation of pancreatic steatosis should be considered in patients with pancreatitis in the setting of metabolic syndrome. 相似文献