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Both qualitative and quantitative changes in mitochondrial DNA (mtDNA) have been implicated in the pathogenesis of diabetes mellitus. In this study, we investigate whether peripheral blood mtDNA (pb-mtDNA) is decreased and if there is any relation between its content and the parameters of both insulin resistance and secretion in offspring of diabetic subjects. The pb-mtDNA content was measured by real time polymerase chain reaction with mitochondrial- specific fluorescent probe, normalized by a nuclear DNA, 28S rRNA gene, in 42 offspring of type 2 diabetic patients and 12 age-, sex- and body mass index (BMI)-matched normal subjects. The correlations between pb-mtDNA content and the parameters of insulin resistance and secretion were studied. Our results indicated that the level of pb-mtDNA was lower in offspring of diabetic subjects than in control subjects (1230 +/- 0.05 vs. 1513 +/- 0.02 in the offspring and control subjects, respectively, P < 0.05). Also, pb-mtDNA content was significantly correlated with logarithmically transformed insulin sensitivity index (r = 0.5, P < 0.05), fasting C-peptide (r = -0.8, P < 0.05), acute insulin response (r = -0.8, P < 0.05) and late insulin response (r = -0.7, P < 0.05) in offspring of diabetic subjects. In conclusion, quantitative mtDNA status might be a hereditary factor associated with type 2 diabetes and is correlated negatively with indexes of insulin resistance and insulin secretion in offspring of diabetic patients. So, pb-mtDNA content could serve as an indicator of insulin sensitivity and insulin secretion in those subjects.  相似文献   
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Background Botulin toxin (BTX) has been proposed as a potential obesity treatment.Methods In a pilot study, the short-term efficacy and safety of BTX was assessed in eight subjects (four men, four women; median age, 46 years; range, 35–57 years) with severe obesity (median body mass index [BMI], 47.1 kg/m2; range 38.2–56.7 kg/m2) and multiple dietary treatment failures. In a single endoscopic session, 500 UI of BTX-A was injected in the gastric antral region.Results No clinically significant side effects were observed. In all patients, despite their not being on a specific diet, a reduction of body weight was observed at 1 month (median baseline weight, 124.4 kg vs 121.8 kg at 1 month; P < 0.05). Two treatment-unrelated dropouts were observed. At 4 months, three of the six patients had a further weight loss. The treatment effect was apparently independent of changes in hunger or satiety, or of changes in fasting and postprandial plasma ghrelin and serum leptin, thus suggesting a different pharmacological mechanism.Conclusions BTX-A treatment appears to be safe and well tolerated by obese patients, while its short-term efficacy varied widely.  相似文献   
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Host defense peptides are immediate responders of the innate immunity that express antimicrobial, immunoregulatory, and wound-healing activities. Neutrophils are a major source for oral host defense peptides, and phagocytosis by neutrophils is a major mechanism for bacterial clearance in the gingival tissue. Dysfunction of or reduction in the numbers of neutrophils or deficiency in the LL-37 host defense peptide was each previously linked with proliferation of oral Aggregatibacter actinomycetemcomitans which resulted in an aggressive periodontal disease. Surprisingly, A. actinomycetemcomitans shows resistance to high concentrations of LL-37. In this study, we demonstrated that submicrocidal concentrations of LL-37 inhibit biofilm formation by A. actinomycetemcomitans and act as opsonins and agglutinins that greatly enhance its clearance by neutrophils and macrophages. Improved uptake of A. actinomycetemcomitans by neutrophils was mediated by their opsonization with LL-37. Enhanced phagocytosis and killing of A. actinomycetemcomitans by murine macrophage-like RAW 264.7 cells were dependent on their preagglutination by LL-37. Although A. actinomycetemcomitans is resistant to the bactericidal effect of LL-37, our results offer a rationale for the epidemiological association between LL-37 deficiency and the expansion of oral A. actinomycetemcomitans and indicate a possible therapeutic use of cationic peptides for host defense.  相似文献   
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Clinical Oral Investigations - To compare the root filling quality, the sealer extrusion, and the healing rates of apical lesions addressed via two endodontic treatment approaches. The hypothesis...  相似文献   
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Hip fracture rates in Norway rank among the highest in the world, more than double that of Spanish women. Previous studies were unable to demonstrate significant differences between the two populations with respect to bone mass or calcium metabolism. In order to test whether the difference in fracture propensity between both populations could be explained by differences in bone material quality we assessed bone material strength using microindentation in 42 Norwegian and 46 Spanish women with normal BMD values, without clinical or morphometric vertebral fractures, no clinical or laboratory signs of secondary osteoporosis, and without use of drugs with known influence on bone metabolism. Bone material properties were assessed by microindentation of the thick cortex of the mid tibia following local anesthesia of the area using the Osteoprobe device (Active Life Scientific, Santa Barbara, CA, USA). Indentation distance was standardized against a calibration phantom of methylmethacrylate and results, as percentage of this reference value, expressed as bone material strength index units (BMSi). We found that the bone material properties reflected in the BMSi value of Norwegian women was significantly inferior when compared to Spanish women (77 ± 7.1 versus 80.7 ± 7.8, p < 0.001). Total hip BMD was significantly higher in Norwegian women (1.218 g/cm2 versus 0.938 g/cm2, p < 0.001) but regression analysis revealed that indentation values did not vary with BMD r2 = 0.03 or age r2 = 0.04. In conclusion Norwegian women show impaired bone material properties, higher bone mass, and were taller than Spanish women. The increased height will increase the impact on bone after falls, and impaired bone material properties may further enhance the risk fracture after such falls. These ethnic differences in bone material properties may partly explain the higher propensity for fracture in Norwegian women. © 2015 American Society for Bone and Mineral Research.  相似文献   
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The growing use of dermal fillers, specifically the use of hyaluronic acid, can be explained by their effectiveness and versatility as well as their favorable safety profiles. Nevertheless, early and late complications with varying levels of severity may occur. The incidence of complications is low and the majority of adverse events are mild (edema, erythema, and local ecchymosis) and of limited duration. However, more severe events, such as ischemia and necrosis, may occur. The symptoms of ischemia can occur immediately after the injection or several hours after the procedure. Here, the authors report three cases of necrosis after hyaluronic acid injection with the first symptoms presenting only several hours after the procedure. The patients were treated immediately after the diagnosis. The aim of this review is to communicate the possibility of the delayed-type presentation of necrosis, present the signs and symptoms that lead to early diagnosis, and review the treatment possibilities of this severe complication.Dermal fillers have been injected with increasing frequency over the past three decades for soft-tissue augmentation by volume expansion in the management of the aging face. In 2012, there were about two million procedures using dermal fillers, according to the American Society of Plastic Surgeons, five percent more than in 2011 and 205 percent more than in 2000, second only to botulinum toxin type A. These minimally invasive and nonsurgical cosmetic procedures were the two most commonly performed in this range of time studied.1,2The growing use of dermal fillers, specifically the use of hyaluronic acid (HA), can be explained by their effectiveness and versatility as well as their favorable safety profiles. Nevertheless, early and late complications with varying levels of severity may occur. The incidence of complications is low and the majority of adverse events are mild (edema, erythema, and local ecchymosis) and of limited duration. However, more severe events, such as ischemia and necrosis, may occur.Injection necrosis is a rare, but important, complication associated with dermal fillers. Necrosis can be attributed to one of two factors—an interruption of vascular supply due to compression or frank obstruction of vessels by direct injection of the material into a vessel itself. The glabella is the injection site commonly believed to be at greater risk for necrosis, but it can also occur at the nasolabial fold.3 Risk factors for intravascular injection include site of application (deep injection of filler products at or near the site of named vessels), volume applied (larger amounts of product can cause a proportionally greater degree of arterial obstruction), and previous scarring (deep tissue scars may stabilize and fix arteries in place, making them easier to penetrate with small sharp needles).4The initial presentation of vascular events may include pain and discomfort disproportionate to what is typically experienced following filler treatments and clinical findings, including blanching, livedo pattern, or violaceous discoloration.4 Although many cases report this immediate post-injection presentation as the typical background seen in a necrosis event, there are few reports with the first symptom presenting only hours after augmentation. See Figures 1 through through3,3, where the authors present three cases of vascular compromise after soft-tissue augmentation with delayed-type presentation. Open in a separate windowOpen in a separate windowFigures 2Aand 2B.Case 2: Necrosis and secondary infection 48 hours after the HA injection (a). Discrete scars in the affected area after treatment (b). Open in a separate windowOpen in a separate windowFigures 1Aand 1B.Case 1: Edema, erythema, and progressive violaceous reticulated patch, livedoid area were observed on the left cheek 36 hours after the injection (a). Complete healing five days after hyaluronidase application and nine days after the HA injection (b). Open in a separate windowOpen in a separate windowFigures 3Aand 3B.Case 3: Necrosis and secondary infection 48 hours after the HA injection (a). Erythema, hipercromia, and discreet scars in the affected area after treatment (b).  相似文献   
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