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21.
Myotonic dystrophy type 1 (DM1) is due to an unstable expansion of CTG repeat in the DMPK gene (19q13.3). The CTG repeat is highly polymorphic (5 to 37) in healthy individuals. According to the hypothesis that expanded (CTG)n alleles originated from larger normal alleles, there may exist a correlation between the prevalence of DM1 and the frequency of large size normal alleles. Strong linkage disequilibrium between different length alleles and the three biallelic markers, Alu, Hinf1 and Taq1, has been reported. OBJECTIVE: To determine the distribution of normal alleles, the frequency of larger normal alleles and analysis of the three biallelic markers, in healthy Iranian controls. MATERIAL AND METHODS: Polymerase chain reaction (PCR) was conducted on two hundred unrelated healthy individuals from different ethnic groups living in Iran to determine the size of the alleles. Markers were analyzed by PCR/RFLP on 174 chromosomes from other control healthy individuals. RESULTS: Our data reveals that 23.7% of alleles had 5 CTG repeats and 7.2% of alleles had > 18 CTG repeats. The analysis of haplotypes revealed that 75% of CTG5 and 80% of CTG > 18 had the (+++) haplotype. CONCLUSION: The frequency of alleles with CTG > 18 in Iran is similar to that of Western Europe and Japan.  相似文献   
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Extraaxillary metastases (i.e., in the absence of axillary involvement) are more likely to develop in patients with inner-quadrant (IQ) breast cancer than in patients with outer-quadrant (OQ) primary tumors. The relative difficulty of identifying extraaxillary metastases may lead to understaging of cancer in these patients. This study examined whether (18)F-FDG PET findings were differentially associated with the location of primary tumors, and with long-term prognosis, in IQ and OQ patients. METHODS: Follow-up data were obtained for 141 patients whose breast cancer was staged by PET and who were documented to have IQ (n = 42) or OQ (n = 99) primaries. Results were stratified according to PET findings consistent with different metastatic patterns. Data were further analyzed with respect to disease outcome after a mean 3-y follow-up period. RESULTS: Among IQ patients, progressive disease was identified in 26.1%, compared with 13.1% of OQ patients, for a relative risk (RR) of 2.0. Of patients with PET findings of isolated extraaxillary metastases, 36.1% had progressive disease, compared with 10.7% of other patients (RR = 3.4), and 61.9% of IQ patients had isolated extraaxillary metastases identified on PET, compared with 10.1% of OQ patients (RR = 6.1). CONCLUSION: IQ patients demonstrated a 6-fold greater frequency of PET findings of isolated extraaxillary metastasis, and such findings were associated with triple the risk for disease progression. Patients with IQ tumors could be vulnerable to understaging with conventional staging approaches and may particularly benefit from PET during the staging process.  相似文献   
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Microgliosis is a common response to multiple types of damage in the CNS. However, the origin of the cells involved in this process is still controversial and the relative importance of local expansion versus recruitment of microglia progenitors from the bloodstream is unclear. Here, we investigated the origin of microglia using chimeric animals obtained by parabiosis. We found no evidence of microglia progenitor recruitment from the circulation in denervation or CNS neurodegenerative disease, suggesting that maintenance and local expansion of microglia are solely dependent on the self-renewal of CNS resident cells in these models.  相似文献   
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The arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is a genetic disease frequently associated with desmosomal mutations, mainly attributed to dominant mutations in the Plakophilin‐2 (PKP2) gene. Naxos and Carvajal are the syndromic forms of ARVD/C due to recessive mutations. Herein, we report an autosomal recessive form of nonsyndromic ARVD/C caused by a mutation in the PKP2 gene. After examination and implementation of diagnostic modalities, the definite diagnosis of ARVD/C was confirmed by detection of ventricular tachycardia with a left bundle branch configuration and a superior axis, T‐wave inversion in right precordial leads (i.e., V1‐V3) in a 12‐lead electrocardiogram, and a right ventricle outflow tract dilatation. Neither cutaneous involvement nor other abnormalities were observed. Genetic testing was performed during which an intronic mutation of c.2577+1G>T in the PKP2 gene was observed homozygously. The c.2577+1G>T disrupts PKP2 mRNA splicing and causes a nonsyndromic form of ARVD/C.  相似文献   
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Secondary chemotherapy for high-risk gestational trophoblastic neoplasia   总被引:4,自引:0,他引:4  
OBJECTIVE: To determine the efficacy of secondary chemotherapy after failure of initial treatment for high-risk gestational trophoblastic neoplasia. METHODS: Twenty-six patients with high-risk gestational trophoblastic neoplasia based on WHO criteria who failed primary treatment or relapsed from remission and received secondary chemotherapy were identified from the records of the Brewer Trophoblastic Disease Center. Initial chemotherapy consisted of etoposide, high-dose methotrexate with folinic acid, actinomycin D, cyclophosphamide and vincristine (EMA-CO) in 10 patients and methotrexate/actinomycin D-based chemotherapy without etoposide in 16 patients. Secondary chemotherapy consisted mainly of platinum-etoposide combinations with methotrexate and actinomycin D (EMA-EP), bleomycin (BEP), or ifosfamide (VIP, ICE). Adjuvant surgery and radiotherapy were used in selected patients. Clinical response and survival as well as factors affecting survival were analyzed retrospectively. RESULTS: The overall survival has 61.5% (16/26). Of the 10 patients who failed primary treatment with EMA-CO, 9 (90%) had complete clinical responses to secondary chemotherapy with EMA-EP (3) or BEP (6), and 6 (60%) were placed into lasting remission. Of the 16 patients who failed primary treatment with methotrexate/actinomycin D-based chemotherapy without etoposide, 10 (63%) had complete clinical responses to BEP (8), VIP (1) and ICE (1), and 10 (63%) achieved long-term remission. Adjuvant surgical procedures were performed on 15 patients as a component of their therapy; eight (73%) of 11 patients who underwent hysterectomy, five (62%) of eight patients who had pulmonary resections, and one patient who had wedge resection of resistant choriocarcinoma from the uterus survived. Survival was significantly influenced by both hCG level at the start of secondary therapy and sites of metastases. CONCLUSION: Patients with persistent or recurrent high-risk gestational trophoblastic neoplasia who develop resistance to methotrexate-containing treatment protocols should be treated with drug combinations employing a platinum agent and etoposide with or without bleomycin or ifosfamide.  相似文献   
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Introduction

The purpose of the present study was the immunohistochemical study of fibronectin (FN) and tenascin (TN) in human tooth pulp capped with mineral trioxide aggregate (MTA) and novel endodontic cement (NEC) (calcium enriched mixture cement) after 2 and 8 weeks.

Methods

Thirty-two premolar teeth that were scheduled for extraction for orthodontic reasons were exposed and capped with either MTA or NEC. The teeth were randomly divided into 4 groups: group 1 (NEC for 2 weeks), group 2 (NEC for 8 weeks), group 3 (MTA for 2 weeks), and group 4 (MTA for 8 weeks). After capping the exposed pulps with either NEC (groups 1 and 2) or MTA (groups 3 and 4), half of the specimens underwent extraction and were prepared for histologic and immunohistochemical evaluation for FN and TN after 2 weeks, and the remaining half were assessed after 8 weeks. FN and TN expression was scored by a blinded pathologist on a scale of I-IV, and the results were analyzed by the Wilcoxon and Mann-Whitney U statistical tests.

Results

FN and TN staining was observed in all 4 experimental groups, and there was no significant difference between expression of FN and TN in any groups. FN and TN staining was observed in the dentinal bridge matrix after 2 weeks under MTA. Expression of both markers reduced significantly after 8 weeks under MTA, and staining was observed only in unmineralized parts of dentinal bridge. FN and TN expression was observed in the matrix of the dentinal bridge after 2 weeks under NEC, and staining of both markers was reduced after 8 weeks compared with 2 weeks. The staining pattern of TN in NEC groups was higher than in MTA groups in both time intervals. However, the difference was not significant.

Conclusions

The present study demonstrated that both MTA and NEC are suitable biomaterials for direct pulp capping and are able to stimulate dentinal bridge formation. Moreover, the role of FN and TN as 2 major components of the matrix of a reparative dentinal bridge was observed.  相似文献   
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