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241.
The regulation of cytoskeletal components in the dendritic shaft core is critical for dendrite elongation and branching. Here, we report that a brain-specific Ras guanine nucleotide exchange factor (RasGEF) carrying two kinase non-catalytic C-lobe domains (KINDs), very-KIND (v-KIND), regulates microtubule-associated protein 2 (MAP2). v-KIND is expressed in developing mouse brain, predominantly in the cerebellar granule cells. v-KIND not only activates Ras small GTPases via the C-terminal RasGEF domain, but also specifically binds to MAP2 via the second KIND domain (KIND2), leading to threonine phosphorylation of MAP2. v-KIND overexpression suppresses dendritic extension and branching of hippocampal neurons and cerebellar granule cells, whereas knockdown of endogenous v-KIND expression promotes dendrite growth. These findings suggest that v-KIND mediates a signaling pathway that links Ras and MAP2 to control dendrite growth.  相似文献   
242.

Background

Intermediate-stage hepatocellular carcinoma (HCC), defined according to the Barcelona Clinic Liver Cancer (BCLC) staging system, is a heterogeneous condition with variable clinical benefits from transarterial chemoembolization (TACE). This study aimed to develop a simple validated prognostic score based on the predictive factors for survival in patients with intermediate-stage HCC treated with TACE.

Methods

Three-hundred and fifty patients with intermediate-stage HCC undergoing initial TACE at Chiba University Hospital (training cohort; n = 187) and two affiliated hospitals (validation cohort; n = 163) were included. Following variables were entered into univariate and multivariate Cox regression models to develop a points-based clinical scoring system: gender, age, etiology, pretreatment, Child–Pugh score, aspartate aminotransferase, creatinine, C-reactive protein, alfa-fetoprotein, size of the largest lesion, and number and location of lesions.

Results

The number of lesions and the Child–Pugh score were identified as independent prognostic factors in the training cohort. The development of a 0–7-point prognostic score, named the Chiba HCC in intermediate-stage prognostic (CHIP) score, was based on the sum of three subscale scores (Child–Pugh score = 0, 1, 2, or 3, respectively, number of lesions = 0, 2, or 3, respectively, HCV-RNA positivity = 0 or 1, respectively). The generated scores were then differentiated into five groups (0–2 points, 3 points, 4 points, 5 points, and 6–7 points) by the median survival time (65.2, 29.2, 24.3, 13.1, and 8.4 months, respectively; p < 0.0001). These results were confirmed in the external validation cohort (p < 0.0001).

Conclusions

The CHIP score is easy-to-use and may assist in finding an appropriate treatment strategy for intermediate-stage HCC.  相似文献   
243.
244.
Four human embryonal carcinoma (EC) cell lines (ITO, NEC 8, NEC 14, NEC 15) derived independently from testicular germ-cell tumors were established in vitro. In their xenografted tumor tissues, all of them exhibited histological characteristics consistent with EC. The cell-biological characterization of these human EC cell lines was investigated with reference to well-known murine EC cell lines. This included examination of their morphology, growth, tumorigenic potential, karyotype, cell-aggregate formation, HLA expression, large glycopeptides, AFP and HCG production, plasminogen-activator secretion, and LDH profiles. Three (ITO, NEC 14, NEC 15) of these human EC cell lines shared cell-biological characteristics consistent with typical EC, but one of them (NEC 8) differed from the others with respect to its rapid growth, high tumorigenic potential, formation of solid cell aggregates, and less differentiated, solid histological pattern. Thus, it is suggested that there are several developmentally different types of human EC cells. The relationship between the properties of these human EC cell lines and their differentiation potential is discussed.  相似文献   
245.
Involvement of Gene 49 in Recombination of Bacteriophage T4   总被引:7,自引:1,他引:6       下载免费PDF全文
The role of T4 gene 49 in recombination was investigated using its conditional-lethal amber (am) and temperature-sensitive (ts) mutants. When measured in genetic tests, defects in gene 49 produced a recombination-deficient phenotype. However, DNA synthesized in cells infected with a ts mutant (tsC9) at a nonpermissive temperature appeared to be in a recombinogenic state: after restitution of gene function by shifting to a permissive temperature, the recombinant frequency among progeny increased rapidly even when DNA replication was blocked by an inhibitor. Growth of a gene 49-defective mutant was suppressed by an additional mutation in gene uvsX, but recombination between rII markers was not.  相似文献   
246.
The method of pulsatile administration of gonadotropin-releasing hormone (Gn-RH) has been proven as a useful means for induction of ovulation in anovulatory women. In our series of clinical trials, 23 out of 29 anovulatory patients ovulated with pulsatile administration of Gn-RH. Seven patients who ovulated volunteered for the present study with daily hormonal analysis and follicular sonometory . Two patients have oligomenorrhea, 3 patients secondary amenorrhea-1st grade (the sole administration of gestagen required for withdrawal bleeding) and the remaining 2 patients secondary amenorrhea-2nd grade (the combined administration of estrogen and gestagen required for withdrawal bleeding). A diagnosis of hyperprolactinemia was made for one patient with secondary amenorrhea-1st grade. Pulsatile administration of Gn-RH was performed by the use of a self-administered infuser . The infuser was connected to an i.v. indwelling catheter via a specially designed blood backflow eliminater . Five micrograms or less of Gn-RH was given every 2 hr from 07:00 to 23:00 hr daily. Five patients received HCG during the preovulatory period. In one patient, a short term treatment of HMG was added to Gn-RH treatment. Follicular sonometry revealed the development of a single dominant follicle which reached between 20 and 28 mm (23.7 +/- 0.12 mm, mean +/- S.E.) in diameter at the preovulatory period. Disappearance of a dominant follicle was recognized in the early luteal phase. Characteristic increases in estradiol were recognized concomitantly with the development of a dominant follicle. Progesterone levels after ovulation were within the limits of its normal "luteal phase" rise. The present data suggest that pulsatile administration of low dose Gn-RH with nocturnal interruption of treatment is effective for normal progress of follicular development in various types of anovulatory patients, culminating in single ovulation. This paper includes the discussion on our method which may be responsible for a high success rate of ovulation induction.  相似文献   
247.
A patient with multiple fibromatosis occurring at the sites of multiple cartilagenous dysplasia was described. Collagen types solubilized with pepsin from the fibromatous tissue were fractionated by a different salt concentration and analyzed by SDS-polyacrylamide gel electrophoresis, which indicated that the tissue produces predominantly "short-chain" collagen. Western blotting of the subunits indicated a cross reaction with antisera of the type VI collagen. The results of rotatory shadowing electron microscopy confirmed the characteristic short-chain structure.  相似文献   
248.
We observed that a YCp-type vector having the centromeric DNA (CEN) sequence previously isolated from the genome, but not a YRp-type vector lacking the CEN sequence, induced pseudohyphal growth in a dimorphic fungi, Candida maltosa, which had been shown to be closely related to Candida albicans by phylogenetic analysis. Deletion analysis of the CEN sequence revealed that the intact CEN sequence was not required for the induction, but part of it, having partial centromeric activity, was enough for the induction. By screening the gene library of this yeast for the sequences which induced pseudohyphal growth, we isolated three different DNA fragments which also had part of the centromere-like sequence. Partial centromeric activity of these fragments was confirmed by three criteria: low copy number and high stability of the plasmids carrying these fragments and rearrangement at high frequency of the plasmid DNA with one of these fragments plus the CEN sequence. Furthermore, when the GGTAGCG sequence commonly found in one copy in each of these four sequences was mutated in the CEN sequence by site-directed mutagenesis, both partial centromeric activity and pseudohyphal growth-inducing activity of the CEN sequence were lost. These results indicated that part of CEN region with partial centromeric activity induces pseudohyphal growth in C. maltosa. It is suggested that some cellular components which interact with the sequence containing GGTAGCG required for centromeric activity are involved in the regulation of the transition between yeast forms and pseudohyphal forms of the cells.  相似文献   
249.
Specific fragmentation with cyanogen bromide and subsequent reduction and carboxymethylation of α1-acid glycoprotein, a normal human plasma globulin, permitted isolation of a large fragment which was shown to represent the amino-terminal half and to contain the total carbohydrate moiety of this protein. The amino acid sequences of two large glycopeptides derived from this fragment were established. One glycopeptide was composed of 22 amino acid residues and one carbohydrate unit, and the other consisted of 65 amino acid residues and carried four carbohydrate units.  相似文献   
250.
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