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Several group B streptococci (GBS) strains resistant to macrolides, lyncomycins, fluoroquinolones, or tetracyclines, are reported in isolates from children or adults patients with invasive infections. Some strains with reduced susceptibility to beta-lactams also are observed among subjects with invasive or noninvasive diseases. Constitutively expressed erm methylase gene confers resistance to both macrolides and lyncomycins, while the tetM gene carried on transposon Tn916 contributes to tetracycline resistance. Significant amino acid substitutions (GyrA, Ser81Leu; ParC, Ser79Phe) in topoisomerases induce resistance to fluoroquinolones, and other substitutions (PBP2X, Gln557Glu and Val405Ala; PBP2B, Gly613Arg) adjacent to significant motifs in penicillin-binding proteins produce decreased beta-lactam susceptibility. Therefore, current interventions concerning prophylaxis and treatment will need to re-evaluate in future.  相似文献   
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SOX9 is a member of the SOX [Sry-related high-mobility group (HMG) box] family and is required for the development and differentiation of multiple cell lineages. To clarify the significance of SOX9 in gastric carcinoma (GC), immunohistochemical expression of SOX9 and the CpG island methylation status of SOX9 were evaluated and compared with clinicopathological factors including overall survival. SOX9 expression was immunohistochemically evaluated in 382 GC tumors and the methylation status was examined in 121 GC tumors. SOX9 expression and its methylation status in six GC cell lines, their Epstein-Barr virus (EBV)-infected cell lines, and two EBV-associated GC cell lines was also examined. The SOX9 expression increased from non-neoplastic mucosa to early cancer. High expression of SOX9 was seen in 212 cases (56%). SOX9 expression was inversely related to advanced tumor stage, vessel infiltration, nodal metastasis, and EBV infection. Fifty-eight (48%) of 121 GC tumors had a methylated promoter in GC and the methylated status was related to low expression. The expression and methylation status were not related to prognosis. Three of six cell lines had increased methylation through EBV infection and decreased SOX9 expression. Upregulation of SOX9 is related to GC development. Downregulation by promoter methylation is related to GC progression and EBV infection. SOX9 is closely related to GC carcinogenesis and EBV-associated GC carcinogenesis.  相似文献   
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Background

Skeletal muscle metabolism is a major determinant of resting energy expenditure (REE). Although the severe muscle loss that characterizes Duchenne muscular dystrophy (DMD) may alter REE, this has not been extensively investigated.

Methods

We studied REE in 77 patients with DMD ranging in age from 10 to 37 years using a portable indirect calorimeter, together with several clinical parameters (age, height, body weight (BW), body mass index (BMI), vital capacity (VC), creatine kinase, creatinine, albumin, cholinesterase, prealbumin), and assessed their influence on REE. In addition, in 12 patients maintaining a stable body weight, the ratio of energy intake to REE was calculated and defined as an alternative index for the physical activity level (aPAL).

Results

REE (kcal/day, mean ± SD) in DMD patients was 1123 (10–11 years), 1186 ± 188 (12–14 years), 1146 ± 214 (15–17 years), 1006 ± 136 (18–29 years) and 1023 ± 97 (?30 years), each of these values being significantly lower than the corresponding control (p < 0.0001). VC (p < 0.001) was the parameter most strongly associated with REE, followed by BMI (p < 0.01) and BW (p < 0.05). The calculated aPAL values were 1.61 (10–11 years), 1.19 (12–14 years), 1.16 (15–17 years), and 1.57 (18–29 years).

Conclusion

The REE in DMD patients was significantly lower than the normal value in every age group, and strongly associated with VC. Both the low REE and PAL values during the early teens, resulting in a low energy requirement, might be related to the obesity that frequently occurs in this age group. In contrast, the high PAL value in the late stage of the disease, possibly due to the presence of respiratory failure, may lead to a high energy requirement, and thus become one of the risk factors for development of malnutrition.  相似文献   
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Purpose

To evaluate the long-term health effects of occupational asbestos exposure, an updated historical cohort mortality study of workers at a refitting shipyard was undertaken.

Methods

The cohort consisted of 249 male ship repair workers (90 laggers, 159 boiler repairers). To determine relative excess mortality, standardized mortality ratios (SMRs) were calculated using mortality rates among the Japanese male population. Mortality follow-up of study subjects was performed for the period from 1947 till the end of 2007.

Results

We identified the vital status of 87 (96.7%) laggers and 150 (94.3%) boiler repairers. Of these, 63 (72.4%) and 95 (63.3%), respectively, died. Laggers, who had handled asbestos materials directly, showed a significantly elevated SMR of 2.64 (95% confidence interval [CI]: 1.06?C5.44) for lung cancer and 2.49 (95% CI: 1.36?C4.18) for nonmalignant respiratory diseases. Boiler repairers, who had many opportunities for secondary exposure to asbestos and a few for direct exposure, showed no significant elevation in SMR for lung cancer but a significantly elevated SMR of 1.78 (95% CI: 1.06?C2.81) for nonmalignant respiratory diseases. In an analysis according to duration of employment, there was a significantly elevated SMR of nonmalignant respiratory diseases in the longer working years group. Among workers from both jobs, no deaths caused by mesothelioma in addition to those in the original study were found and no subject died from larynx cancer.

Conclusion

This updated study confirmed a significant excess of asbestos-related mortality from diseases such as lung cancer and nonmalignant respiratory diseases among workers in a refitting shipyard in Japan.  相似文献   
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