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51.
1. Hyaluronic acid was detected as the largest glycosaminoglycan component in the glycosaminoglycan fraction from purified nuclei of regenerating livers as in the case of normal livers (Furukawa, K. and Tarayama, H. (1977) Biochim. Biophys. Acta 499, 278--289). However, the nuclear content of glycosaminoglycans tended to decrease after partial hepatectomy, reaching one-third of the normal liver level at 24--30 h after partial hepatectomy. On the other hand, two new polyanionic components were detected in the glycosaminoglycan fraction from regenerating liver nuclei. 2. One of these new components seems to be a sulfated glycopeptide. The 35SO4 incorporation into this component was stimulated biphasically after partial hepatectomy; the first stimulation occurring immediately after partial hepatectomy and the second stimulation occurring almost in parallel to the DNA synthesis. 3. Another polyacnionic component which also increases in the nuclear content after partial hepatectomy lacks hexuronic acid, sialic acid and 35SO4 and yet it is intensely stained by Alcian Blue. Preliminary investigations revealed the presence of hexose, ribose and phosphate as the major components. 4. In contrast to the primary localization of hyaluronic acid in the chromatin fraction and also in the nonhistone chromosomal protein fraction from it, these new polyanionic components were detected mainly in the karyosol fraction.  相似文献   
52.
Thirty-one isomers of polychlorinated biphenyl (PCB) were examined for biodegradability by two species of Alcaligenes and Acinetobacter. The following relationships between chlorine substitution and biodegradability of PCBs were observed. (i) Degradation decreased as chlorine substitution increased. PCB isomers containing more than four chlorines were less susceptible to degradation. (ii) PCBs containing two chlorines on either the ortho position of a single ring (i.e., 2,6-) or on both rings (i.e., 2,2′-) showed very poor degradability. (iii) PCBs containing all chlorine atoms on only a single ring were generally degraded faster than when the same number of chlorines were substituted on both rings. (iv) Preferential ring fission of the molecules occurred with nonchlorinated or lesser chlorinated rings. (v) The formation and accumulation of a yellow intermediate was always observed in 4′-chloro-substituted PCBs. (vi) Significant differences between the two organisms with respect to degradability were not observed except for 2,4,6-trichlorobiphenyl.  相似文献   
53.
Human cytomegalovirus stimulates host cell RNA synthesis.   总被引:14,自引:14,他引:0       下载免费PDF全文
Human cytomegalovirus infection of human fibroblast cells (WI-38) induced cellular RNA synthesis. The RNA synthesis in infected cultures preceded the synthesis of viral DNA and progeny virus by approximately 24 h. RNA species synthesized in infected cells included ribosomal 28S and 18S; and 4S transfer RNA; all were markedly increased in comparison to uninfected cells. This induction of host cell RNA synthesis was dependent upon a protein(s) that was synthesized during the early stages of infection.  相似文献   
54.
In this paper, four fungi collected in Nansei Islands are reported. One is Strasseria garciniae, which must be transferred to the genus Phyllosticta. This fungus was collected in Okinawa Main Island and Iriomote Island. The other three fungi are newly added to the Japanese fungal flora. Phyllosticta ghaesembillae on Codiaeum variegatum and Cercospora asplenii on Asplenium antiquum were collected in Yoron Island. The last one, Coniella australiensis on Eucalyptus robusta was collected in Okinawa Main Island. Their morphology and symptoms on the host plant are described, with some mycological notes.  相似文献   
55.
56.
Landscape and Ecological Engineering - Investigating factors underlying human-wildlife conflicts in agricultural landscapes is important for both preventing crop damage and wildlife conservation....  相似文献   
57.
PurposeEndometrial carcinoma (EC) is a clinically heterogeneous disease characterized by a number of different histological subtypes, and its heterogeneity may be involved in the accumulation of multiple genetic alterations. The aim of this work was to investigate the comprehensive mutational profile of EC tumors, and examine the associations between somatic mutations and clinicopathological features or survival in EC patients.MethodsA total of 100 surgical tumors were obtained from EC patients who had previously undergone surgery. Genomic DNA samples extracted from fresh-frozen tissues were analyzed using the Ion AmpliSeq Cancer Hotspot Panel v2 Kit, covering 50 tumor-related genes.ResultsValidated mutations were detected in 91 of the 100 tumors (91%) and identified in eight of the most frequently mutated genes, namely PTEN (57%), PIK3CA (51%), TP53 (30%), KRAS (23%), CTNNB1 (21%), FBFR2 (13%), FBXW7(10%) and RB1 (9%). PTEN mutations were found to associated with young age (< 60), early-stage, endometrioid histology, non-recurrence and better overall survival (OS). CTNNB1 mutations were associated with young age, endometrioid histology and better OS. On the other hands, TP53 mutations were associated with late-stage, non-endometrioid histology, high-grade, recurrence and worse OS. FBWX7 mutations were associated with late-stage, vascular invasion and lymph node metastasis. FGFR2 mutations correlated with deep (≥ 1/2) myometrial invasion.ConclusionOur comprehensive mutational profile will be useful for understanding and evaluating the molecular characteristics of EC tumors, and may lead to the establishment of novel treatment strategies that improve the survival of patients with EC in the future.  相似文献   
58.

Introduction

Articular chondrocytes undergo an obvious phenotypic change when cultured in monolayers. During this change, or dedifferentiation, the expression of type I and type III procollagen is induced where normal chondrocytes express little type I and type III procollagen. In this study, we attempted to determine the mechanism(s) for the induction of such procollagen expression in dedifferentiating chondrocytes.

Methods

All experiments were performed using primary-cultured human articular chondrocytes under approval of institutional review boards. Integrin(s) responsible for the induction of type I and type III procollagen expression were specified by RNAi experiments. The signal pathway(s) involved in the induction were determined by specific inhibitors and RNAi experiments. Adenovirus-mediated experiments were performed to identify a small GTPase regulating the activity of integrins in dedifferentiating chondrocytes. The effect of inhibition of integrins on dedifferentiation was investigated by experiments using echistatin, a potent disintegrin. The effect of echistatin was investigated first with monolayer-cultured chondrocytes, and then with pellet-cultured chondrocytes.

Results

In dedifferentiating chondrocytes, α5β1 integrin was found to be involved in the induction of type I and type III procollagen expression. The induction was known to be mediated by v-akt murine thymoma viral oncogene homolog (AKT) signaling. Among the three AKT isoforms, AKT1 seemed to be most involved in the signaling. Elated RAS viral (r-ras) oncogene homolog (RRAS) was considered to regulate the progression of dedifferentiation by modulating the affinity and avidity of α5β1 integrin to ligands. Echistatin inhibited dedifferentiation of monolayer-cultured chondrocytes. Furthermore, the matrix formed by pellet-cultured chondrocytes more closely resembled that of normal cartilage compared with the controls.

Conclusions

The result of this study has shown, for the first time, that α5β1 integrin may be responsible for the induction of non-cartilaginous collagen expression in chondrocytes undergoing dedifferentiation. Again, this study has shown that the inhibition of ligand ligation to integrins may be an effective strategy to inhibit phenotypic change of cultured chondrocytes, and to improve the quality of matrix synthesized by primary cultured chondrocytes.  相似文献   
59.
Abstract

2′-Deoxy- and 2′-O-methyl-5′-O-terpyridyl derivatives of adenosine and cytidine were synthesized and used to construct 5′-end-modified oligonucleotides. These antisense agents complexed with Cu(II) exclusively cleaved a complementary RNA oligomer at the site opposite the terpyridine-nucleoside residue. We also found that the terpyridine·Cu(II) moiety stabilizes 2′-O-methyl RNA duplex. These suggest that after RNA hybridization, the terpyridine moiety is close to the RNA strand, presumably in an end capping manner.  相似文献   
60.

Aims

Roles of glucagon-like peptide-1 (GLP-1) in extra-pancreatic tissues remain unclear. The aim of this study was to examine determinants of GLP-1 secretory function and possible contribution of GLP-1 to blood pressure (BP) regulation.

Methods and Results

We recruited 128 subjects who received annual examinations and 75g-oral glucose tolerance tests (OGTT) in the Tanno-Sobetsu cohort. Subjects on regular medications for cardiovascular and/or metabolic diseases were excluded, and data for the remaining 103 subjects were used for the univariate and multivariate analyses. Age, plasma glucose (PG), hemoglobin A1c (HbA1c), plasma insulin, and serum lipids were not selected as independent determinants of fasting GLP-1 level by multiple linear regression analysis. However, age and female sex were selected as independent positive determinants of the area under the curve of GLP-1 level during OGTT (AUCGLP-1), an index of GLP-1 secretory function. Multiple linear regression analysis indicated that AUCGLP-1 was an independent negative predictor of systolic BP (SBP), while AUCGLP-1 was not correlated with fasting PG or HbA1c level. In subgroup analyses using the median of AUCGLP-1 to divide the study subjects into high and low GLP-1 response groups, AUCGLP-1 was significantly correlated with both SBP and diastolic BP (r = 0.40 and 0.28, respectively) in the low GLP-1 response group but not in the high GLP-1 response group.

Conclusions

The results of the present study suggest that GLP-1 secretory function is involved in prevention of BP elevation and that the GLP-1 response to oral glucose rather increases with aging perhaps as an adaptive phenomenon.  相似文献   
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