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71.
The pathogenesis of male osteoporosis at the cellular level is still elusive. We performed histomorphometric analysis of bone biopsy samples from 51 eugonadal men with idiopathic osteoporosis. Their median age was 54 (range 29–73) years. Eighty-two percent of the patients had a fracture history, and 57% had vertebral fractures. Bone volume, trabecular thickness, wall thickness, and osteoid thickness were significantly reduced in osteoporotic men compared with healthy men. Erosion depth was similar, as were the bone remodeling parameters such as bone formation rate, mineral apposition rate, and activation frequency. In the osteoporotic men, osteoid thickness was correlated to bone mineral density at the lumbar spine (R 2 = 0.19, P < 0.01); together with wall thickness, the two parameters could explain 27% of the variation in lumbar spine bone mineral density. The osteoid thickness was correlated to anthropometric variables such as body weight (R 2 = 0.24, P < 0.001) and body mass index (R 2 = 0.14, P < 0.01), as well as to serum estradiol levels (R 2 = 0.14, P < 0.01) and to the ratio insulin-like growth factor-1 (IGF-1) to IGF-binding protein-1 (IGFBP-1) (R 2 = 0.12, P < 0.01). Regression analysis showed that 36% of the variation in osteoid thickness could be predicted by body weight and estradiol levels. In conclusion, bone histomorphometry in male idiopathic osteoporosis was characterized by thin bone structural units, which might suggest osteoblast dysfunction. Bone histomorphometry parameters were associated with low body weight, low estradiol levels, and increased levels of IGFBP-1, supporting the notion that estrogens and IGFs play regulatory roles in male bone turnover.  相似文献   
72.
OBJECTIVE: Ileal pouch anal anastomosis (IPAA) is the preferred method for restorative surgery in patients with ulcerative colitis who have to undergo proctocolectomy. The most common complication is pouchitis and several studies have pointed to the microbiota of the pouch as being a risk factor. The aim of this study was to follow the development of the bacterial microbiota in pouches during the first year. MATERIAL AND METHODS: Terminal restriction fragment length polymorphism (T-RFLP) combined with cloning and sequencing was used to identify the most predominant bacteria on the different sampling occasions. A total of 274 clones were grouped by T-RFLP and clones from each group were selected for sequencing and identified by comparison with known sequences. RESULTS: Differences in T-RFLP profiles and clone libraries were found between the patients, and also in changes apparent in each patient at different time-points. The main bacterial groups in the pouches resembled those of the normal colonic microbiota, with a predominance of the clostridia clusters XIVa and IV, Bacteroides and Enterobacteriaceae. Exceptions were clones with sequences resembling those of the Clostridium perfringens group, in both patients and on all sampling occasions, and the dominance of clones resembling Turicibacter in one of the patients at the time of pouch construction. CONCLUSIONS: The pouch microbiota showed similarities to the normal colon microbiota except for the presence of clones with sequences resembling those of the C. perfringens group and Turicibacter. The bacterial composition differed between the two patients and the microbiota changed with time, suggesting that the composition is not stable during the first year.  相似文献   
73.
BACKGROUND: D-galactosamine together with lipopolysaccharide can lead to a pronounced secretion by Kupffer cells of pro-inflammatory mediators, which have been shown to be early and important mediators of liver injury. Probiotics and dietary supplementation with fruit or vegetable extracts with high content of antioxidants, such as blueberry, could be beneficial in protecting against hepatotoxicity. AIMS: To investigate whether blueberry and probiotics could attenuate liver injury induced by D-galactosamine and lipopolysaccharide. SUBJECTS: Sprague-Dawley rats were used. METHODS: Six experimental groups: acute liver injury control and five groups of liver injury treated by blueberry alone or by each of the probiotics strains (Lactobacillus plantarum DSM 15313 and Bifidobacterium infantis DSM 15159) with and without blueberry. Samples were collected 24 h after induction for bacterial test, liver function test, short chain fatty acids, myeloperoxidase, cytokines, malondialdehyde and glutathione. RESULTS: Alanine aminotransferase levels decreased significantly in all groups compared to liver injury control and DSM 15313 groups. Bilirubin, liver TNF-alpha, myeloperoxidase and acetic acid in cecum content decreased significantly in all groups, while liver glutathione values increased significantly in all groups compared to liver injury control. Liver IL-1beta and bacterial translocation to the liver and mesenteric lymph nodes decreased significantly in all groups except B. infantis DSM 15159 group compared to the liver injury control. Enterobacteriaceae count in cecum decreased significantly in the groups with blueberry plus probiotics compared to the other groups. CONCLUSION: Blueberry and probiotics exert protective effects on acute liver injury. They reduce the hepatocytes injury, the inflammation and the pro-inflammatory cytokines, and improve the barrier functions and antioxidant activity.  相似文献   
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Intramyocellular lipids are of importance in lipid-related diseases. The techniques in this field are limited because of a lack of adequate tools for localization of various lipids. The most usual methods for the localization of lipid distribution in the skeletal muscle are histochemistry and fluorescence probes. Different chromatography methods and mass spectrometry techniques have also been used for lipid identification. Our aim was to localize the spatial distribution of lipids in their native forms by using static time-of-flight secondary-ion mass spectrometry (TOF-SIMS). Human percutaneous skeletal muscle biopsies were obtained from the middle part of the lateral vastus muscle in the right leg of healthy adolescents with a body mass index >30. Samples were prepared by high-pressure freezing, freeze-fracturing and freeze-drying, and analysed by imaging TOF-SIMS equipped with a Bi3+ cluster ion gun. In the positive spectra, we identified phosphocholine, cholesterol, diacylglycerol, phospholipids and triacylglycerol. Phosphocholine was localized to the edge of the fibre, representing the sarcoplasma or endomysium. Weak cholesterol signals were observed in the intracellular areas. High diacylglycerol and low triacylglycerol signal intensities were seen in intracellular spaces of the transversal area of the muscle fibre. In the negative spectra, we identified fatty acids. We observed co-localization of fatty acids and diacylglycerol, which may indicate lipid-storing parts of the skeletal muscle. Thus, TOF-SIMS imaging can be used to depict the heterogeneous localization of lipids in human skeletal muscle.  相似文献   
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Tumour necrosis factor (TNF)‐α antagonists are very effective treatments for immune‐mediated inflammatory disorders. Adverse events include severe infections and episodes of lupus‐like syndrome, multiple sclerosis‐like demyelination and other neuropathies. The pathomechanisms of these autoimmune‐like syndromes after TNF‐α blockade are still unknown. We report a patient with psoriasis who developed a lupus‐like syndrome during infliximab treatment, which was finally diagnosed as an exaggerated systemic infection with Borrelia burgdorferi. This case suggests that autoimmune‐like syndromes may actually represent pre‐existing or newly acquired nonseptic bacterial or viral infections, which have escaped immune surveillance during TNF‐α blockade. Each autoimmune‐like syndrome during TNF‐α blockade should therefore be carefully examined for potential causative infection.  相似文献   
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80.
Darier disease (DD) is an autosomal dominant skin disease. Treatment is often difficult and unsatisfactory because of the chronic nature of the condition and the irritant potential of various therapeutic agents. Systemic vitamin A derivatives such as acitretin and isotretinoin are the treatment of choice, but their use is often limited by class‐specific side‐effects. Alitretinoin (9‐cis‐retinoic acid), has antiproliferative and anti‐inflammatory potential, and is licensed for the systemic treatment of chronic hand eczema in a number of countries. Unlike acitretin, alitrenoin requires contraception in women of childbearing age to be extended for only 1 month after the end of treatment. There is evidence that alitretinoin might be a well‐tolerated alternative for the systemic treatment of various retinoid‐responsive skin diseases. We present two cases of women with refractory DD successfully treated with alitretinoin without marked side‐effects, who both obtained near‐complete remission of their skin lesions.  相似文献   
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