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It is unclear how tau gene mutations cause frontotemporal dementia (FTD) with parkinsonism linked to chromosome 17 (FTDP-17), but those in exon 10 (E10) or the following intron may be pathogenic by altering E10 splicing, perturbing the normal 1:1 ratio of four versus three microtubule-binding repeat tau (4R:3R tau ratio) and forming tau inclusions. We report on a 55-year old woman with frontotemporal dementia and a family history of FTDP-17 in whom we found a novel E12 (Glu342Val) tau gene mutation, prominent frontotemporal neuron loss, intracytoplasmic tau aggregates, paired helical tau filaments, increased 4R tau messenger RNA, increased 4R tau without E2 or E3 inserts, decreased 4R tau with these inserts, and a 4R:3R tau ratio greater than 1 in gray and white matter. Thus, this novel Glu342Val mutation may cause FTDP-17 by unprecedented mechanisms that alter splicing of E2, E3, and E10 to preferentially increase 4R tau without amino terminal inserts and promote aggregation of tau filaments into cytopathic inclusions.  相似文献   
33.
Primary hyperparathyroidism (PHPT) is known to cause diverse subjective symptoms, in addition to those related to osteitis fibrosa cystica and kidney stones. The treatment of the disease ameliorates the subjective symptoms and improves the patients’ quality of life. In this prospective study, patients undergoing surgery for incidentally detected, mild, asymptomatic PHPT were assessed to determine whether subjective neuropsychological symptoms are improved even in patients with “asymptomatic” PHPT. From October 1995 to March 2004, 25 patients who had one or more neuropsychological symptoms preoperatively and were followed up 1 year after parathyroidectomy were enrolled. The subjective symptoms were identified using questionnaires distributed to patients; eight questions were used to determine the presence or absence of psychoneurological symptoms. Compared to their preoperative status, patients responded that their general health perceptions 1 year after surgery were improved (13 cases, 52%), unchanged (11 cases, 44%), or aggravated (1 case, 4%). There were no statistically significant differences in the patients’ responses before and after surgery with respect to individual neuropsychological symptoms, such as “tiring easily, “forgetfulness,” “decreased concentration,” “depression,” “irritability,” “uneasiness,” and “sleeplessness.” Therefore, subjective neuropsychological symptoms did not improve in otherwise asymptomatic PHPT patients following parathyroidectomy. However, patients’ questionnaire responses may not reflect their actual status as accurately as laboratory examination results. Overall, 52% of patients were subjectively satisfied with surgery; this may result from patients’ expectations of treatment.  相似文献   
34.
Sinonasal carcinomas arise from the respiratory epithelium that lines the nasal and paranasal cavities, and are histologically composed of either squamous or cylindrical cell carcinoma. However, molecular analysis with the purpose of distinguishing sinonasal carcinomas from other head and neck squamous cell carcinomas (HNSCCs), which arise from squamous epithelium, has been limited. Moreover, a wide range of frequency of microsatellite instability (MSI) in HNSCC has been reported. Using high-resolution fluorescent microsatellite analysis (HFRMA), we studied microsatellite alterations in 34 patients with sinonasal carcinoma. As a control, 24 oral squamous cell carcinomas were used. MSI was detected in 14 patients with sinonasal carcinoma (41%), but not in any with oral squamous cell carcinoma (p=0.002). Furthermore, in sinonasal carcinoma, 11 out of 17 (65%) T1-T3 sinonasal carcinomas demonstrated MSI, whereas only 3 out of 15 (20%) T4 tumors demonstrated MSI. Immunohistochemically, sinonasal carcinoma showed a higher MIB-1-labeling index and more frequently showed cytokeratin 18 expression when compared with oral squamous cell carcinoma. These findings suggest that sinonasal carcinoma and HNSCC have quite different molecular backgrounds regarding carcinogenesis, and the role of MSI is relatively minor in cases of advanced sinonasal carcinoma.  相似文献   
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Developmental toxicity of estrogenic chemicals on rodents and other species   总被引:2,自引:0,他引:2  
ABSTRACT  Antenatal sex-hormone exposure induces lesions in mouse reproductive organs, which are similar to those in humans exposed in utero to a synthetic estrogen, diethylstilbestrol. The developing organisms including rodents, fish and amphibians are particularly sensitive to exposure to estrogenic chemicals during a critical window. Exposure to estrogens during the critical period induces long-term changes in reproductive as well as non-reproductive organs, including persistent molecular alterations. The antenatal mouse model can be utilized as an indicator of possible long-term consequences of exposure to exogenous estrogenic compounds including possible environmental endocrine disrupters. Many chemicals released into the environment potentially disrupt the endocrine system in wildlife and humans, some of which exhibit estrogenic activity by binding to the estrogen receptors. Estrogen responsive genes, therefore, need to be identified to understand the molecular basis of estrogenic actions. In order to understand molecular mechanisms of estrogenic chemicals on developing organisms, we are identifying estrogen responsive genes using cDNA microarray, quantitative RT-PCR, and differential display methods, and genes related to the estrogen-independent vaginal changes in mice induced by estrogens during the critical window. In this review, discussion of our own findings related to endocrine distuptor issue will be provided.  相似文献   
37.
We studied the effect of traditional herbal medicines containing daio (Rhei Rhizoma) on the long-term progression of diabetic nephropathy with overt proteinuria in eight patients [mean age 60 (45-73) years; duration of diabetes 18 (7-36) years]. At the beginning of the study, mean HbA1c was 8.2% and mean serum creatinine was 1.0 +/- 0.3 mg/dl. Everypatient had diabetic neuropathy and retinopathy. Three of the patients had hypertension and four had ischemic heart disease. After 107 +/- 25 months, the mean serum creatinine level had significantly increased to 4.8 +/- 2.6 mg/dl. The mean serum creatinine levels of five patients not advancing to dialysis treatment increased from 1.2 +/- 0.3 to 3.2 +/- 1.0 mg/dl, and the three patients requiring dialysis increased from 0.8 +/- 0.1 to 7.5 +/- 2.1 mg/dl. In the control group, treated without traditional herbal medicines, the mean serum creatinine level had significantly increased from 1.0 +/- 0.3 to 9.5 +/- 1.9 mg/dl after 71 +/- 12 months. All of the control group required dialysis treatment. Diabetic nephropathy with overt proteinuria is reported to develop into renal failure after 6-7 years. In this retrospective study, traditional herbal medicines with Daio were considered to be effective in prolonging the pre-dialysis period of diabetic nephropathy.  相似文献   
38.
The bacteria (Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Klebsiella spp. and Pseudomonas aeruginosa) isolated from patients diagnosed as urinary tract infections (UTIs) in 10 institutions in Japan were supplied between September and December, 2001. Then, the susceptibilities of these bacteria to various antimicrobial agents were examined, and the results were compared with those obtained between 1992 and 2000. Comparison was made by classifying strains isolated from patients into those in uncomplicated UTIs and those in complicated UTIs (including with or without indwelling catheter). The drug sensitivity of S. aureus in this year was comparable to those in up to the previous year, and S. aureus showed the best susceptibility to vancomycin (VCM). E. faecalis showed good susceptibility to ampicillin and imipenem, and the MIC90s were 2 micrograms/mL. The susceptibility of E. faecalis to VCM was also good. E. coli showed good susceptibility to the drugs except penicillins. Among cephems, the susceptibility to cefozopran (CZOP) was better (MIC90: < or = 0.125 microgram/mL). Just as the last report, the decreases in susceptibility of E. coli to quinolones were also observed in the patients with complicated UTIs. The susceptibility of Klebsiella spp. to all the test drugs did not significantly change in 2001 and was generally good but not to penicillins. Among cephems, Klebsiella spp. showed good susceptibility to flomoxef, cefpirome, cefixime, and CZOP with < or = 0.125 microgram/mL of MIC90s either in uncomplicated or complicated UTIs. Although the drug sensitivity of P. aeruginosa was generally low, the detection of the strains that showed good susceptibility to quinolones and carbapenems (MIC: < or = 0.125-2 micrograms/mL) were relatively frequent.  相似文献   
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40.
In patients with Type 2 diabetes mellitus (Type 2 DM), the relationship between the prevalence rate of small dense LDL (sdLDL) and parameters of lipid metabolism was analyzed using the method devised by modified Krauss method using apoferritin as an internal standard. The prevalence rate of sdLDL was 34% compared with it of normal subjects in this study. When the severity of Type 2 DM was classified into three groups of the HbA1c value, neither the sdLDL size nor its prevalence rate differed significantly depending upon the severity of the Type 2 DM. Also, when the prevalence rate of sdLDL was analyzed in relation to the severity of complications, i.e., of microangiopathy (retinopathy and nephropathy) or macroangiopathy (cerebral infarction), there was no significant difference in the prevalence rate of sdLDL depending on the severity of any of these complications. On the other hand, the prevalence rate of sdLDL was found to be correlated with the serum TG level. The serum level of TG-rich remnants (metabolites of TG) was also high in patients with sdLDL. It should take notice that the assessment of sdLDL should be used the authorized method for the evaluation. Thus it is concluded that the levels of sdLDL were important in evaluation of Type 2 DM. The prevalence rate of sdLDL did not correlate with the severity, nor the modalities for the complications of Type 2 DM.  相似文献   
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