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11.
Alterations in intestinal microbiota are associated with obesity and insulin resistance. We studied the effects of infusing intestinal microbiota from lean donors to male recipients with metabolic syndrome on the recipients' microbiota composition and glucose metabolism. Subjects were assigned randomly to groups that were given small intestinal infusions of allogenic or autologous microbiota. Six weeks after infusion of microbiota from lean donors, insulin sensitivity of recipients increased (median rate of glucose disappearance changed from 26.2 to 45.3 μmol/kg/min; P < .05) along with levels of butyrate-producing intestinal microbiota. Intestinal microbiota might be developed as therapeutic agents to increase insulin sensitivity in humans; www.trialregister.nl; registered at the Dutch Trial Register (NTR1776).  相似文献   
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We studied the presence of secondary Sjögren's syndrome (SS) and the composition of saliva, prevalence of oral pathogens, periodontitis, mouth mucosa, and teeth in patients with various rheumatic diseases and in healthy controls. The hypothesis was that different rheumatic diseases might cause differences in oral health characteristics because of the liability of secondary SS in the patients. The study involved 77 patients and 77 age-matched and sex-matched controls. Twenty patients were suffering from spondylarthropathy (SPA), 18 from ankylosing spondylitis (AS), 24 from rheumatoid arthritis (RA), and 15 from mixed connective tissue disease (MCTD). Clinical and radiographic oral health status was recorded and salivary flow rates were measured. Selected salivary proteins and immunoglobulins were analysed by routine methods. Minor salivary gland biopsy samples were taken from the patients for assessment of inflammatory focus scores. Differences between patients and controls and in between the different rheumatic diseases were analysed statistically. Secondary SS was diagnosed in 39% (30/77) of the patients. A severe periodontal condition (community periodontal index of treatment needs score 3 or 4) occurred in 58% (45/77) of the rheumatic patients compared with only 26% (20/77) of the controls (p<0.0001). The severity of focal sialadenitis (focus score) correlated significant with salivary IgA, IgG, and IgM concentrations. Salivary albumin, total protein, IgG, and IgM concentrations were higher in all patient groups than in the controls. The number of patients with low salivary flow rates was higher in all patient groups compared to controls. Oral yeast counts were significantly higher in the patients than in the controls (p<0.001). In a subgroup analysis, patients with SS had higher values for salivary IgA and IgM than patients without SS. Dental caries and oral lactobacilli were more frequent in patients with SS, but SS was not associated with periodontitis. No major differences were noted in other salivary biochemical parameters between these two groups. Patients with rheumatic diseases, irrespective of specific diagnosis, thus had various alterations in salivary flow and composition and oral health. The findings may reflect the autoimmune inflammation of the salivary glands frequently observed in these patients.  相似文献   
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Background and purpose High age is associated with increased postoperative mortality, but the factors that predict mortality in older hip and knee replacement recipients are not known.

Methods Preoperative clinical and operative data on 1,998 primary total hip and knee replacements performed for osteoarthritis in patients aged ≥ 75 years in a single institution were collected from a joint replacement database and compoared with mortality data. Average follow-up was 4.2 (2.2–7.6) years for the patients who survived. Factors associated with mortality were analyzed using Cox regression analysis, with adjustment for age, sex, operated joint, laterality, and anesthesiological risk score.

Results Mortality was 0.15% at 30 days, 0.35% at 90 days, 1.60% at 1 year, 7.6% at 3 years, and 16% at 5 years, and was similar following hip and knee replacement. Higher age, male sex, American Society of Anesthesiologists risk score of > 2, use of walking aids, preoperative walking restriction (inability to walk or ability to walk indoors only, compared to ability to walk > 1 km), poor clinical condition preoperatively (based on clinical hip and knee scores or clinical severity of osteoarthritis), preoperative anemia, severe renal insufficiency, and use of blood transfusions were associated with higher mortality. High body mass index had a protective effect in patients after hip replacement.

Interpretation Postoperative mortality is low in healthy old joint replacement recipients. Comorbidities and functional limitations preoperatively are associated with higher mortality and warrant careful consideration before proceeding with joint replacement surgery.  相似文献   
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The aim of this study was to assess the utility of Fourier transform infrared mapping to study the drug release phenomena within a hydrophobic matrix tablet. Starch acetate with a degree of substitution (2.7) was used as a hydrophobic matrix former. Anhydrous caffeine and riboflavin sodium phosphate were used as water soluble model drugs. The USP (XXVIII) paddle-method was selected as an in vitro dissolution test. Mapping of the diluted tablets' cross-section was performed by attenuated total reflection mode. Fourier transform infrared mapping can distinguish drug particles from the bulk matrix and it can be considered as a valuable method for obtaining both quantitative and qualitative information on drug release processes. The physicochemical properties of the drug compound strongly contribute to its release behavior when the USP paddle in vitro dissolution test is used. Mapping of the riboflavin product revealed a more homogenous matrix distribution due to its smaller particle size. Consequently, its dissolution release profile was more uniform than caffeine which possessed a wider particle size distribution and lower solubility. Mapping showed that caffeine became localized in the lower part of the tablet unlike riboflavin. The hydrodynamic conditions during the in vitro release test might contribute to this differentiation.  相似文献   
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Central intraosseous adenoid cystic carcinoma (ACC) of the mandible, formerly known as cylindroma, is a rare neoplasm with only 16 cases reported in the literature. We describe the diagnosis, etiology, and treatment of a central ACC located in the mandibular premolar region. We also review the literature. This case illustrates 2 key facts regarding the diagnosis and etiology of ACC. First, central salivary gland tumors should be considered in the differential diagnosis of cystic lytic lesions in the mandible. Second, even though the origin of this type of tumor is still unknown, the presence of ectopic tissue anterior to the submandibular gland in the submandibular area indicates that this tumor might be made up of ectopic embryogenic inclusions.  相似文献   
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We have examined (1) the frequency of B cells secreting antibodies against donor major histocompatibility complex (MHC) antigens and (2) the properties of Thy-1-antigen-expressing leukocytes in rats rejecting renal allografts. Our results show that B cells secreting antibodies are present in the inflammatory cell population at the frequency of 1:850. Among them only 1 out of 2-150 is engaged in production of antibodies directed to the graft MHC antigens, depending on the method of assay. This suggests that despite the observed significant production of nonspecific immunoglobulin in situ, only a minority of the B-cell population is specifically committed to the graft MHC antigens. This finding is concordant with the described previously low frequencies of the T cells specifically directed toward the graft MHC antigen. The role of the "immunologically noncommitted" cells in graft rejection is unknown. We have found that a substantial part (up to 60%) of inflammatory cells invading a rat kidney allograft express the Thy-1 antigen. This suggests that they might be immature (progenitor?) cells and, therefore, unable to respond to the graft antigens. Progenitor-like properties of these cells have been confirmed by their ability to reconstitute lethally irradiated syngeneic rat. Finally, these immature cells are of lymphoid, not of myeloid, linkage, because they do not proliferate in the presence of GM-CSF.  相似文献   
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