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11.
Transformation of MMC-E epithelial cells by acute 3611-MSV: inhibition of collagen synthesis and induction of novel polypeptides 总被引:2,自引:0,他引:2
Mouse embryo epithelial cells MMC-E were transformed by novel fibrosarcoma-inducing murine sarcoma virus 3611-MSV. The cells were analyzed for the production and deposition of pericellular glycoproteins by immunofluorescence and by radioactive metabolic and cell surface labeling techniques followed by analysis in polyacrylamide gels and fluorography. The pericellular fibronectin matrix was lost, but unlike in virus-transformed fibroblastic cells, the production of fibronectin was not affected. The major differences detected were decrease in collagen production and initiation of synthesis of two major glycoproteins with Mr 58,000 and 60,000. Cell surface carbohydrate labeling indicated that after 3611-MSV transformation the cells expressed Mr 100,000 and 68,000 polypeptides. The present and previous results show that viral transformation of epithelial cells induces different transformed phenotypes that are associated with distinct alterations in pericellular glycoproteins. 相似文献
12.
The caecal epithelium of Calicotyle kröyeri consists of a single cell type which functions in the uptake and intracellular digestion of host epidermis and associated mucus. Each cell is columnar with a small basal nucleus and prominent nucleolus. Perinuclear cytoplasm contains narrow profiles of GER and mitochondria with numerous cristae. Golgi complexes are small and indistinct. Most of the cell is filled with vacuoles of heterogeneous content, the largest occupying the cell apex. There is in each cell an apical endocytotic complex comprising cell surface lamellae, apical vesicles and numerous tubular invaginations of the plasmalemma. The limiting membrane of all these components is structurally modified and bears a highly organized array of peg-like structures on its luminal surface. The complex is capable of ingesting particulate food material from the gut lumen for transfer, via vesicles, to the vacuoles for digestion. Most of the vacuoles represent the digestive elements of the cell and, histochemically, are reactive for protein, mucus and carboxylic esterases. Indigestible residues and lipid droplets accumulate in the large apical vacuole and are periodically released to the lumen by exocytosis. Small, undifferentiated caecal cells were occasionally observed in the epithelium, but their development has not been recorded. 相似文献
13.
Jonathan W. Yewdell 《Molecular & cellular proteomics : MCP》2022,21(7):100230
In the 35 years since the revelation that short peptides bound to major histocompatibility complex class I and II molecules are the secret of the major histocompatibility complex–restricted nature of T-cell recognition, there has been enormous progress in characterizing the immunopeptidome, the repertoire of peptide presented for immunosurveillance. Here, the major milestones in the journey are marked, the contribution of proteasome-mediated splicing to the immunopeptidome is discussed, and exciting recent findings relating the immunopeptidome to the translatome revealed by ribosome profiling (RiboSeq) is detailed. Finally, what is needed for continued progress is opined about, which includes the infusion of talented young scientists into the antigen-processing field, currently undergoing a renaissance; thanks in part to the astounding success of T-cell–based cancer immunotherapy. 相似文献
14.
Yuka Kitamura Miho Tanaka Chiho Muramatsu Yasushi Akahori Hiroyuki Tsuda Yoshinobu Hattori 《Biochemical and biophysical research communications》2009,383(4):480-484
We reported comprehensive screening for antigens (Ags) overexpressed on various carcinomas via isolation of human monoclonal antibodies (mAbs) that may be therapeutic in a previous paper (Proc. Natl. Acad. Sci. USA 105, 7287-7292, 2008). Twenty-one distinct Ags highly expressed on several carcinomas were identified and 356 mAbs with unique sequences turned out to bind to one of the 21 Ags. Among them CADM1/IGSF4 which had been originally referred to as tumor suppressor lung cancer 1 (TSLC1) was included. Therefore we examined the expression of CADM1 in lung cancers in this study. Eight different anti CADM1 mAbs were used for immunohistochemical analysis of 29 fresh lung cancer specimens. Staining patterns were categorized to six groups based on the extent of positive staining and the localization of stained portions. While overexpression of CADM1 was observed on the cell surface of adenocarcinomas at a high frequency, around 60%, positive stainings were rarely observed on that of other lung carcinomas including squamous cell carcinomas. Moreover, some clones among the eight mAbs gave different staining patterns from those by the other clones against the same fresh specimen, suggesting presence of variant forms of CADM1 differentiated by mAbs. 相似文献
15.
Maria Schwaederle Gregory A Daniels David E Piccioni Santosh Kesari Paul T Fanta Richard B Schwab Kelly A Shimabukuro Barbara A Parker Razelle Kurzrock 《Cell cycle (Georgetown, Tex.)》2015,14(11):1730-1737
Next generation sequencing is transforming patient care by allowing physicians to customize and match treatment to their patients’ tumor alterations. Our goal was to study the association between key molecular alterations and outcome parameters. We evaluated the characteristics and outcomes (overall survival (OS), time to metastasis/recurrence, and best progression-free survival (PFS)) of 392 patients for whom next generation sequencing (182 or 236 genes) had been performed. The Kaplan-Meier method and Cox regression models were used for our analysis, and results were subjected to internal validation using a resampling method (bootstrap analysis). In a multivariable analysis (Cox regression model), the parameters that were statistically associated with a poorer overall survival were the presence of metastases at diagnosis (P = 0.014), gastrointestinal histology (P < 0.0001), PTEN (P < 0.0001), and CDKN2A alterations (P = 0.0001). The variables associated with a shorter time to metastases/recurrence were gastrointestinal histology (P = 0.004), APC (P = 0.008), PTEN (P = 0.026) and TP53 (P = 0.044) alterations. TP53 (P = 0.003) and PTEN (P = 0.034) alterations were independent predictors of a shorter best PFS. A personalized treatment approach (matching the molecular aberration with a cognate targeted drug) also correlated with a longer best PFS (P = 0.046). Our study demonstrated that, across diverse cancers, anomalies in specific tumor suppressor genes (PTEN, CDKN2A, APC, and/or TP53) were independently associated with a worse outcome, as reflected by time to metastases/recurrence, best PFS on treatment, and/or overall survival. These observations suggest that molecular diagnostic tests may provide important prognostic information in patients with cancer. 相似文献
16.
H W Huizinga 《Experimental parasitology》1973,33(2):350-364
Larval trematode antagonism between Ribeiroia marini and Schistosoma mansoni was studied in the snail Biomphalaria glabrata. A laboratory-raised Puerto Rican strain of B. glabrata was exposed to single and double infections with given numbers of: (1) embryonated eggs of R. marini from laboratory rats, and (2) miracidia of S. mansoni from mice. Snails were maintained in outside environmental tanks in San Juan, Puerto Rico and larval trematode interactions were examined in a series of five experiments. Snails of all sizes were highly susceptible to single infections with R. marini. Rediae and cercariae caused extensive damage to the digestive gland and ovotestis resulting in premature death of snails. Heavily infected snails were castrated and stopped laying eggs. Snails infected first with S. mansoni were only partly susceptible to superinfection with R. marini given on Day 23. In a reverse experiment, snails infected first with R. marini were only partly susceptible to a second infection with S. mansoni given on Day 23. In simultaneous exposures, snails developed double infections (22%) with R. marini dominant and S. mansoni sporocyst and cercaria production reduced. While R. marini is not a strong direct antagonist against established S. mansoni infections, it has several attributes as a possible biological control agent: hardy eggs easily produced in rats; high infectivity to snails of all ages; and ability to castrate and prematurely kill B. glabrata. The R. marini-rat system described here provides a convenient laboratory and field model for the study of intrasnail trematode antagonism and biological control. 相似文献
17.
《Somatosensory & motor research》2013,30(4):206-209
AbstractUsing diffusion tensor tractography, we investigated the anatomical location of medial lemniscus (ML) and spinothalamic tract (STT) at pons. We recruited 47 healthy volunteers. Evaluation of the anatomical location of ML and STT was performed using the highest probabilistic location at the upper, middle, and lower pons. According to findings, MLs were located around the middle to medial one-third, between midline and lateral boundary of pons in the pontine tegmentum and STTs were located posterolaterally to ML. 相似文献
18.
19.
Valerie J. Paul Robert W. Thacker Kenneth Banks Stjepko Golubic 《Coral reefs (Online)》2005,24(4):693-697
Benthic cyanobacteria of the genus Lyngbya can form prominent mats and blooms in tropical and subtropical coral reef and seagrass habitats worldwide. A Lyngbya bloom on the reef tract offshore of Broward County, Florida, was first noted in 2002, and although it is seasonally variable
in its distribution and abundance, it has persisted and spread over the past 3 years. In this study, the most abundant species
of Lyngbya found in the blooms have been identified and compared to other species of Lyngbya by morphological and molecular methods. The most common species of Lyngbya is consistent with the properties of Lyngbya confervoides C. Agardh. The 16S ribosomal DNA sequence shares 88–92% identity with other known Lyngbya sequences, suggesting that this bloom consists primarily of a new, previously unsequenced species of Lyngbya. The second most common Lyngbya in the bloom is consistent with Lyngbya polychroa. This persistent bloom is a concern because it smothers octocorals and other invertebrates and negatively impacts these southeastern
Florida reefs. 相似文献
20.
Joji Sekine Kazuo Sano Masataka Uehara Tsugio Inokuchi 《Biotechnic & histochemistry》1996,71(3):152-156
A technique Is described for rapid detection of S-pha?e cells of tumor tissues in smear specimens using bromodeoxyuridine (BrdU) immunostaining. Mouse NR-S1 tumors and human tumor specimens were prepared for smear cytology after incubation in RPMI 1640 culture medium containing 200 μM BrdU at 37 °C under 3 atm for 1 hr. Samples were fixed in 70% ethanol for 30 min and used immediately or air dried for 30 min. Samples were then denatured in either 4 N HC1 or 0.07 N NaOH to prepare partially single-stranded DMA. Fixation with air drying for 30 min followed by 30 min in 70% ethanol and 1 min denaturation with 0.07 N NaOH resulted in satisfactory staining quality. Cultured tumor specimens were processed for routine paraffin sections after smears were made for cytology. The labeling indices of the smear specimens and of the paraffin sections gave similar results. This technique should be useful in evaluating the cell proliferative potential of tumor tissue in smear cytology without processing paraffin sections. 相似文献