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91.

Objective

This study analyzed the clinicopathological correlation between ovarian cancer (OC) and RECQL1 DNA helicase to assess its therapeutic potential.

Methods

Surgically resected OC from 118 retrospective cases, for which paraffin blocks and all clinical data were complete, were used in this study. RECQL1 and Ki-67 immunostaining were performed on sections to correlate RECQL1 staining with subtype and patient survival. Ten OC and two normal cell lines were then examined for RECQL1 expression and were treated with siRNA against RECQL1 to assess its effect on cell proliferation.

Results

Of the 118 cases of adenocarcinoma (50, serous; 26, endometrioid; 21, clear cell; 15, mucinous; 6, other histology), 104 (90%) showed varying levels of RECQL1 expression in the nuclei of OC cells. The Cox hazards model confirmed that diffuse and strong staining of RECQL1 was correlated with histological type. However, RECQL1 expression did not correlate with overall patient survival or FIGO stage. In vitro, RECQL1 expression was exceptionally high in rapidly growing OC cell lines, as compared with normal cells. Using a time-course analysis of RECQL1-siRNA transfection, we observed a significant inhibition in cell proliferation.

Conclusions

RECQL1 DNA helicase is a marker of highly proliferative cells. RECQL1-siRNA may offer a new therapeutic strategy against various subtypes of OC, including platinum-resistant cancers, or in recurrent cancers that gain platinum resistance.  相似文献   
92.
A new breeding process for Aspergillus sojae involving protoplast fusion was studied to obtain more desirable koji-molds for soy-sauce production, especially as to their enzyme productivities. A pair of double-marker mutants with characteristic enzyme-productivities, derived from genealogically unrelated A. sojae cultures, were fused by means of the protoplast fusion technique. The fusants were UV-treated, and stable heterozygous diploids were obtained. Further improvement of their enzyme-productivities was attempted using two approaches. Through the usual mutation of the heterozygous diploids, the activities of protease and glutaminase were simultaneously improved to a certain extent. Through the haploidization of the heterozygous diploids with benomyl or p-fluorophenylalanine (FPA), some haploids considered phenotypically to be recombinants were segregated, in addition to a large number of haploids that had reverted to the original double marker mutants. On screening these haploid-recombinants, the authors obtained a few more excellent recombinants, as to their enzyme productivities, that is, strains producing as much protease as the hyper-protease producer and producing almost as much glutaminase as the hyper- glutaminase producing parent. It has been shown that mutation or especially haploidization of heterozygous diploids produced by cell-fusion could be a very useful technique for the breeding of new industrial koji-molds.  相似文献   
93.
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95.
The skeleton of the siliceous sponges (Porifera: Hexactinellida and Demospongiae) is supported by spicules composed of bio-silica. In the axial canals of megascleres, harboring the axial filaments, three isoforms of the enzyme silicatein (-alpha, -beta and -gamma) have been identified until now, using the demosponges Tethya aurantium and Suberites domuncula. Here we describe the composition of the proteinaceous components of the axial filament from small spicules, the microscleres, in the demosponge Geodia cydonium that possesses megascleres and microscleres. The morphology of the different spicule types is described. Also in G. cydonium the synthesis of the spicules starts intracellularly and they are subsequently extruded to the extracellular space. In contrast to the composition of the silicateins in the megascleres (isoforms: -alpha, -beta and -gamma), the axial filaments of the microscleres contain only one form of silicatein, termed silicatein-alpha/beta, with a size of 25kDa. Silicatein-alpha/beta undergoes three phosphorylation steps. The gene encoding silicatein-alpha/beta was identified and found to comprise the same characteristic sites, described previously for silicateins-alpha or -beta. It is hypothesized, that the different composition of the axial filaments, with respect to silicateins, contributes to the morphology of the different types of spicules.  相似文献   
96.
97.
In atrophic parotid glands induced by liquid diet, acinar cell apoptosis is increased while proliferative activity is reduced. This study aimed to clarify how liquid diet affects submandibular and sublingual glands, including acinar cell apoptosis and proliferation. Seven-week-old male Wistar rats were fed either a liquid (experimental group) or pellet diet (control group) from 3 to 21 days, respectively. Submandibular and sublingual glands were weighed and examined histologically, ultrastructurally, and immunohistochemically using antibodies to cleaved caspase-3 (Casp-3) and 5-bromo-2′-deoxyuridine (BrdU). Weights of submandibular and sublingual gland from the experimental group were not significantly different from controls at any time point. Histological and ultrastructural characteristics of experimental acinar cells in both glands were normal. Acinar cells in control and experimental submandibular glands were positively stained with periodic acid Schiff (PAS) and weakly stained by alcian blue (AB). In control and experimental sublingual glands, mucous acinar cells were PAS-positive and strongly AB-positive. Although Casp-3- and BrdU-positive acinar cells were identified in both glands in the experimental group, their labeling indices were not significantly different from controls. In conclusion, liquid diet in rats does not induce atrophic alterations to acinar cells, including apoptosis and proliferative activity in submandibular and sublingual glands.  相似文献   
98.
Diseases threaten the structure and function of marine ecosystems and are contributing to the global decline of coral reefs. We currently lack an understanding of how climate change stressors, such as ocean acidification (OA) and warming, may simultaneously affect coral reef disease dynamics, particularly diseases threatening key reef-building organisms, for example crustose coralline algae (CCA). Here, we use coralline fungal disease (CFD), a previously described CCA disease from the Pacific, to examine these simultaneous effects using both field observations and experimental manipulations. We identify the associated fungus as belonging to the subphylum Ustilaginomycetes and show linear lesion expansion rates on individual hosts can reach 6.5 mm per day. Further, we demonstrate for the first time, to our knowledge, that ocean-warming events could increase the frequency of CFD outbreaks on coral reefs, but that OA-induced lowering of pH may ameliorate outbreaks by slowing lesion expansion rates on individual hosts. Lowered pH may still reduce overall host survivorship, however, by reducing calcification and facilitating fungal bio-erosion. Such complex, interactive effects between simultaneous extrinsic environmental stressors on disease dynamics are important to consider if we are to accurately predict the response of coral reef communities to future climate change.  相似文献   
99.

Background

The 2011 Japan massive tsunami traumatized many children. The aim of this study was to assess changes in strengths and difficulties experienced in home and school by among surviving children after the 2011 tsunami, in comparison with published normal Japanese data.

Methods

In November 2012 (20 months after the disaster) and September 2013 (30 months after the disaster), the Strengths and Difficulties Questionnaire (SDQ), a questionnaire on children''s strengths and difficulties in home and school activities, were distributed to 12,193 and 11,819 children, respectively. An effective response of children 20 months and 30 month after the disaster was obtained in 10,597 children (86.9%), and 10,812 children (91.4%), respectively. The SDQ scores evaluated by parents and teachers were compared with published normal Japanese SDQ scores.

Results

The SDQ scores (emotional problems, conduct problems, hyperactivity/inattention, peer relationship problems, and total difficulty score) evaluated by parents of children in the 4th to 9th grade who were evaluated after 30 and 20 months were significantly high compared with the published normal data of children without traumatic experiences (all P<0.001). The SDQ scores (prosocial behavior) evaluated by teachers of children in the 4th to 9th grade who were evaluated after 30 and 20 months were significantly low compared with the published normal data of children without traumatic experiences (all P<0.001).

Conclusions

This study showed that the experience of the disaster affected those children with prosocial behaviors towards teachers and friends at school. However, no significant changes (in their prosocial attitude) had been seen at home, where they continued to keep their respect and caring feelings for parents. These results indicate that for accurate diagnosis, clinicians should not only evaluate these children''s daily activities at home but also try to objectively assess their daily activities at school.  相似文献   
100.
Two species of the genus Ponticulomyces collected from Japan for the first time are described and illustrated. Ponticulomyces kedrovayae is characterized by its lamellae staining yellow when bruised and in age, stipe lacking an annulus and a pseudorhiza, scattered pileal hairs, and large amygdaliform basidiospores. It mainly occurs on dead wood of Fagus crenata. Ponticulomyces orientalis is characterized by its scattered pileal hairs and broadly ellipsoid to ellipsoid basidiospores. It was collected mostly on dead wood of Cameria japonica.  相似文献   
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