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141.
K. Chummun, M. Fitzpatrick, P. Lenehan, P. Boylan, E. Mooney and G. Flannelly
Diagnostic and therapeutic dilemma associated with atypical glandular cells on liquid‐based cervical cytology Background: In 2008, the management of women in Ireland with atypical glandular cells changed to immediate referral to colposcopy. The optimal management of these women is unclear. A balance between the detection of occult disease and overtreatment is required. Methods: Our study aim was to document the experience of this policy at the National Maternity Hospital, Dublin. Information from the computerized data management system was analysed with the statistical package SPSS. Results: In 2009, 156 women attended colposcopy following a single atypical glandular cell diagnosis on liquid‐based cytology. The mean age was 41 years. Thirty (19.2%) women had abnormal vaginal bleeding, 31 (19.9%) were smokers and 34 (21.8%) had received previous treatment. The colposcopy was satisfactory in 125 (80.1%) and unsatisfactory in 31 (19.9%). Cervical histology was available for 146 (93.6%) women: 57 excisional procedures and 89 diagnostic biopsies. Abnormal histology was detected in 46 women (31.5%). Four women (2.7%) had invasive cancer, five (3.4%) had adenocarcinoma in situ, 21 (14.4%) had cervical intraepithelial neoplasia (CIN) grade 2 or 3 and 16 (11.0%) had CIN1. No abnormality was detected in 100 women (68.5%), including 35 (61.4%) of those who had undergone excisional procedures. The colposcopic impression in this group was unsatisfactory in 10 women (28.6%), glandular abnormalities in six (17.1%), high‐ and low‐grade changes in 12 (34.2%) and six (17.1%) women, respectively, and normal in one (2.9%). The findings were essentially negative in the remaining 10 women: overall, 30 (19.2%) of the 156 women referred to colposcopy had at least CIN2. Conclusion: This study confirmed significant levels of high‐grade disease in women referred to colposcopy with atypical glandular cells on cytology. Concerns about undetected endocervical disease resulted in high levels of negative excisional biopsies. Alternative strategies, including endometrial sampling, human papillomavirus testing and discussion at clinicopathological meeting, should be considered.  相似文献   
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COM1/SAE2 is a highly conserved gene from yeast to higher eukaryotes. Its orthologs, known to cooperate with the MRX complex (Mre11/Rad50/Xrs2), are required for meiotic DNA double‐strand break (DSB) ends resection and specific mitotic DSB repair events. Here, the rice (Oryza sativa, 2n = 2x = 24) COM1/SAE2 homolog was identified through positional cloning, termed OsCOM1. Four independent mutants of OsCOM1 were isolated and characterized. In Oscom1 mutants, synaptonemal complex (SC) formation, homologous pairing and recombination were severely inhibited, whereas aberrant non‐homologous chromosome entanglements occurred constantly. Several key meiotic proteins, including ZEP1 and OsMER3, were not loaded normally onto chromosomes in Oscom1 mutants, whereas the localization of OsREC8, PAIR2 and PAIR3 seemed to be normal. Moreover, OsCOM1 was loaded normally onto meiotic chromosomes in Osrec8, zep1 and Osmer3 mutants, but could not be properly loaded in Osam1, pair2 and OsSPO11‐1RNAi plants. These results provide direct evidence for the functions of OsCOM1 in promoting homologous synapsis and recombination in rice meiosis.  相似文献   
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A cross sectional study on hepatobiliary abnormalities in opisthorchiasis was performed in 8936 males and females aged from 20 to 60 years from 90 villages of Khon Kaen province, Northeast Thailand. All were stool-examined for Opisthorchis viverrini infection by standard quantitative formalin/ethyl acetate concentration technique. Of these, 3359 participants with stool egg positive underwent ultrasonography of the upper abdomen. The hepatobiliary abnormalities detected by ultrasound are described here. This study found a significantly higher frequency of advanced periductal fibrosis in persons with chronic opisthorchiasis (23.6%), particularly in males. Risks of the fibrosis included intensity of infection, and age younger than 30 years. Height of left lobe of the liver, cross-section of the gallbladder dimensions post fatty meal, sludge, and, interestingly, intrahepatic duct stones were significantly associated with the advanced periductal fibrosis. Eleven suspected cholangiocarcinoma (CCA) cases were observed. This study emphasizes the current status of high O. viverrini infection rate and the existence of hepatobiliary abnormalities including suspected CCA in opisthorchiasis endemic areas of Thailand.  相似文献   
147.

Background

Multislice computed tomography (MSCT) can be used to detect myocardial bridging (MB) of coronary arteries. However, most published studies included small cohorts and did not collect data about predictors. We investigated prevalence and predictors of MB in an Indonesian population.

Methods

All patients who had MSCT at Cinere Hospital, Jakarta, Indonesia between 2006 and 2009 were included in a prospective registry. MB was defined when at least half of the coronary artery was imbedded within the myocardium with a normal epicardial course of the proximal and distal portion.

Results

Of the 934 patients (mean age 53 years, 37.8 % female), MB could be observed in 152 patients (16.3 %). Patients with MB were younger compared with those without MB. Coronary risk factors were not different between the two groups. Coronary calcifications and moderate to severe coronary stenoses were less prevalent in patients with MB, also after adjusting for differences in age. At the time of diagnosis, only a few patients with MB were treated with beta-blockers (35 %) or calcium channel blockers (13 %).

Conclusions

Prevalence of myocardial bridging as detected by MSCT is relatively high. Patients with MB were younger and had a lower prevalence of coronary sclerosis. MB could be the cause of their unexplained symptoms. Follow-up studies are necessary to assess the symptoms of these patients, their response to treatment and the incidence of (coronary) events. MSCT can be used to identify patients for potential new treatment strategies.  相似文献   
148.
Accurate chromosome segregation during mitosis and meiosis is regulated and secured by several distinctly different yet intricately connected regulatory mechanisms. As chromosomal instability is a hallmark of a majority of tumors as well as a cause of infertility for germ cells, extensive research in the past has focused on the identification and characterization of molecular components that are crucial for faithful chromosome segregation during cell division. Shugoshins, including Sgo1 and Sgo2, are evolutionarily conserved proteins that function to protect sister chromatid cohesion, thus ensuring chromosomal stability during mitosis and meiosis in eukaryotes. Recent studies reveal that Shugoshins in higher animals play an essential role not only in protecting centromeric cohesion of sister chromatids and assisting bi-orientation attachment at the kinetochores, but also in safeguarding centriole cohesion/engagement during early mitosis. Many molecular components have been identified that play essential roles in modulating/mediating Sgo functions. This review primarily summarizes recent advances on the mechanisms of action of Shugoshins in suppressing chromosomal instability during nuclear division in eukaryotic organisms.  相似文献   
149.
雌核发育二倍体鲫鲤Dmc1基因的全长cDNA克隆及表达分析   总被引:1,自引:0,他引:1  
Dmc1(disrupted meiotic cDNA)基因是一个在减数分裂前期Ⅰ表达的特异基因,其产物是减数分裂前期Ⅰ同源染色体配对所必需的。根据据酵母菌、小鼠以及人的DMC1中保守的氨基酸基序设计简并引物,PCR扩增克隆获得了第四代雌核发育二倍体鲫鲤(G4)Dmc1基因部分cDNA序列。在此基础上,通过RACE获得了G4Dmc1基因全长cDNA序列,长度为1369bp,其中开放阅读框为1029bp,编码含342个氨基酸的蛋白质。同时,系统进化分析表明,在进化过程中Dmc1基因在鱼类中保持着高度保守的进化特征。RT-PCR结果表明,Dmc1基因只在G4性腺中表达,在其他组织中不表达。通过实时荧光定量PCR,对Dmc1基因在G4和普通鲤鱼的早期卵巢的表达进行分析,发现G4表达比鲤鱼高。由此可见,雌核发育二倍体鲫鲤Dmc1基因也是减数分裂特异基因,而且其高表达暗示雌核发育二倍体鲫鲤具有正常的减数分裂过程并且其早期性腺存在着多倍体卵原细胞。  相似文献   
150.
Different types of malformations are likely to affect the morphology of diatoms when exposed to particularly unstable environmental conditions, the most easily identifiable being distortion of the whole frustule. In the present study, we investigated, by means of SEM, valve abnormalities induced by high cadmium contamination (100 μg · L?1) in small pennate diatoms. Changes in the shape of Amphora pediculus (Kütz.) Grunow and anomalous sculpturing of the cell wall of many species, such as Encyonema minutum (Hilse) D. G. Mann, Mayamaea agrestris (Hust.) Lange‐Bert., Gomphonema parvulum (Kütz.) Kütz., or Eolimna minima (Grunow) Lange‐Bert., were observed, which were not, or almost not, noticeable in the LM. With consideration to current knowledge of diatom morphogenesis, metal uptake by the cell would induce, directly or indirectly, damage to many cytoplasmic components (e.g., microtubules, cytoskeleton, Golgi‐derived vesicles) involved in the precisely organized silica deposition. This study confirms that many species, whatever their size, are likely to exhibit morphological abnormalities under cadmium stress, and that this indicator may be valuable for the biomonitoring of metal contamination, even if SEM observations are not necessary for routine studies.  相似文献   
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