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181.
E-selectin modulates the malignant properties of T84 colon carcinoma cells   总被引:7,自引:0,他引:7  
The extravasation of metastatic cells is regulated by molecular events involving the initial adhesion of tumor cells to the endothelium and subsequently the migration of cells in the host connective tissue. E-selectin on endothelial cells and sialyl Lewis X carbohydrate component on tumor cells are mainly involved in the adhesion of colon carcinoma cells to the endothelium of target organ. Interaction of T84 colon cancer cells to purified E-selectin in vitro caused an increase in the tyrosine phosphorylation of a number of proteins as well as the modulation of cellular properties correlated to the metastatic phenotype. Specifically, E-selectin-stimulated actin reorganization, increased collagenase secretion, and induced cell migration. Treatment of T84 cells with herbimycin A inhibited cell adhesion as well as selectin-induced increase of cell migration, and cytoskeleton assembly. Our data demonstrate that binding of cancer cells to E-selectin starts signal transduction pathways which may affect the tumor metastatic abilities.  相似文献   
182.
Ultraviolet radiation (UVR) phototherapy is a promising new treatment for inflammatory airway diseases. However, the potential carcinogenic risks associated with this treatment are not well understood. UV-specific DNA photoproducts were used as biomarkers to address this issue. Radioimmunoassay was used to quantify cyclobutane pyrimidine dimers (CPDs) and (6–4) photoproducts in DNA purified from two milieus: nasal mucosa samples from subjects exposed to intranasal phototherapy and human airway (EpiAirway™) and human skin (EpiDerm™) tissue models. Immunohistochemistry was used to detect CPD formation and persistence in human nasal biopsies and human tissue models. In subjects exposed to broadband ultraviolet radiation, DNA damage frequencies were determined prior to as well as immediately after treatment and at increasing times post-treatment. We observed significant levels of DNA damage immediately after treatment and efficient removal of the damage within a few days. No residual damage was observed in human subjects exposed to multiple UVB treatments several weeks after the last treatment. To better understand the molecular response of the nasal epithelium to DNA damage, parallel experiments were conducted in EpiAirway and EpiDerm model systems. Repair rates in these two tissues were very similar and comparable to that observed in human skin. The data suggest that the UV-induced DNA damage response of respiratory epithelia is very similar to that of the human epidermis and that nasal mucosa is able to efficiently repair UVB induced DNA damage.  相似文献   
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184.
Trimming of mannose residues from the N-linked oligosaccharide precursor is a stringent requirement for glycoprotein endoplasmic reticulum (ER)-associated degradation (ERAD). In this paper, we show that, surprisingly, overexpression of ER degradation-enhancing α-mannosidase-like protein 1 (EDEM1) or its up-regulation by IRE1, as occurs in the unfolded protein response, overrides this requirement and renders unnecessary the expression of ER mannosidase I. An EDEM1 deletion mutant lacking most of the carbohydrate-recognition domain also accelerated ERAD, delivering the substrate to XTP3-B and OS9. EDEM1 overexpression also accelerated the degradation of a mutant nonglycosylated substrate. Upon proteasomal inhibition, EDEM1 concentrated together with the ERAD substrate in the pericentriolar ER-derived quality control compartment (ERQC), where ER mannosidase I and ERAD machinery components are localized, including, as we show here, OS9. We suggest that a nascent glycoprotein can normally dissociate from EDEM1 and be rescued from ERAD by reentering calnexin-refolding cycles, a condition terminated by mannose trimming. At high EDEM1 levels, glycoprotein release is prevented and glycan interactions are no longer required, canceling the otherwise mandatory ERAD timing by mannose trimming and accelerating the targeting to degradation.  相似文献   
185.
The syllid fauna of three locations in Crete and Israel (eastern Mediterranean Sea) was studied, yielding 82 syllid species, many of which were found for the first time in the respective areas: Seventeen species were recorded for the first time on the Israeli coasts and 20 in Greek waters. Perkinsyllis augeneri (Hartmann-Schröder, 1979) and Prosphaerosyllis chauseyensis Olivier et al., 2011 are new records for the Mediterranean Sea. Detailed information is given on the morphology, ecology and distribution of the species recorded for the first time in the studied areas. In addition, an update on the distribution of the genus Prosphaerosyllis San Martín, 1984 in the Mediterranean is given and an identification key to the Mediterranean species is provided.  相似文献   
186.

Background

A multicentre case-control study based on sentinel practitioner surveillance networks from seven European countries was undertaken to estimate the effectiveness of 2009–2010 pandemic and seasonal influenza vaccines against medically attended influenza-like illness (ILI) laboratory-confirmed as pandemic influenza A (H1N1) (pH1N1).

Methods and Findings

Sentinel practitioners swabbed ILI patients using systematic sampling. We included in the study patients meeting the European ILI case definition with onset of symptoms >14 days after the start of national pandemic vaccination campaigns. We compared pH1N1 cases to influenza laboratory-negative controls. A valid vaccination corresponded to >14 days between receiving a dose of vaccine and symptom onset. We estimated pooled vaccine effectiveness (VE) as 1 minus the odds ratio with the study site as a fixed effect. Using logistic regression, we adjusted VE for potential confounding factors (age group, sex, month of onset, chronic diseases and related hospitalizations, smoking history, seasonal influenza vaccinations, practitioner visits in previous year). We conducted a complete case analysis excluding individuals with missing values and a multiple multivariate imputation to estimate missing values. The multivariate imputation (n = 2902) adjusted pandemic VE (PIVE) estimates were 71.9% (95% confidence interval [CI] 45.6–85.5) overall; 78.4% (95% CI 54.4–89.8) in patients <65 years; and 72.9% (95% CI 39.8–87.8) in individuals without chronic disease. The complete case (n = 1,502) adjusted PIVE were 66.0% (95% CI 23.9–84.8), 71.3% (95% CI 29.1–88.4), and 70.2% (95% CI 19.4–89.0), respectively. The adjusted PIVE was 66.0% (95% CI −69.9 to 93.2) if vaccinated 8–14 days before ILI onset. The adjusted 2009–2010 seasonal influenza VE was 9.9% (95% CI −65.2 to 50.9).

Conclusions

Our results suggest good protection of the pandemic monovalent vaccine against medically attended pH1N1 and no effect of the 2009–2010 seasonal influenza vaccine. However, the late availability of the pandemic vaccine and subsequent limited coverage with this vaccine hampered our ability to study vaccine benefits during the outbreak period. Future studies should include estimation of the effectiveness of the new trivalent vaccine in the upcoming 2010–2011 season, when vaccination will occur before the influenza season starts. Please see later in the article for the Editors'' Summary  相似文献   
187.
188.
A new lanostane aldehyde, charantal (1), was isolated from the ethanolic leaf extract of Momordica charantia together with the known compound, 2,4-bis(2-phenylpropan-2-yl)phenol (2). The structure of compound 1 was elucidated by extensive 1D and 2D NMR and MS experiments. Compound 2 displayed a moderately strong antitubercular activity against Mycobacterium tuberculosis H37Rv (MIC = 14 μg/mL) according to the MABA susceptibility assay.  相似文献   
189.
Agonist-induced lipolysis of adipose fat is robustly inhibited by insulin or by feedback inhibition by the long-chain fatty acids (LCFA) produced during lipolysis. However, the mode of action of LCFA in suppressing adipose lipolysis is not clear. β,β'-Tetramethyl hexadecanedioic acid (Mββ/ EDICA16) is a synthetic LCFA that is neither esterified into lipids nor β-oxidized, and therefore, it was exploited for suppressing agonist-induced lipolysis in analogy to natural LCFA. Mββ is shown here to suppress isoproterenol-induced lipolysis in the rat in vivo as well as in 3T3-L1 adipocytes. Inhibition of isoproterenol-induced lipolysis is due to decrease in isoproterenol-induced cAMP with concomitant inhibition of the phosphorylation of hormone-sensitive lipase and perilipin by protein kinase A. Suppression of cellular cAMP levels is accounted for by inhibition of the adenylate cyclase due to suppression of Raf1 expression by Mββ-activated AMPK. Suppression of Raf1 is further complemented by induction of components of the unfolded-protein-response by Mββ. Our findings imply genuine inhibition of agonist-induced adipose lipolysis by LCFA, independent of their β-oxidation or reesterification. Mββ suppression of agonist-induced lipolysis and cellular cAMP levels independent of the insulin transduction pathway may indicate that synthetic LCFA could serve as insulin mimetics in the lipolysis context under conditions of insulin resistance.  相似文献   
190.
Autologous AD-MSC [adipose-derived MSC (mesenchymal stem cell)] therapy involves harvesting fat from the patient by isolating the stem and regenerative cells and administering the cells back to the patient. This study evaluated the production of canine AD-MSCs and their possible application in cellular therapy for dogs. To assess whether cellular therapy can replace drug therapy, the clinical effect of a single intra-articular injection of AD-MSCs was evaluated on 4 dogs with lameness associated with OA (osteoarthritis) of the humeroradial joints. MSCs were readily isolated from adult dog adipose tissue, and their ability to form colony and differentiate into various phenotypes was confirmed. AD-MSCs expressed OCT4, NANOG and SOX2 at the mRNA level, pluripotency markers usually ascribed to embryonic stem cells. The results suggest the stemness of the cells isolated from canine fat, and good quality control made them available for both experimental and clinical use. Follow-up studies to evaluate the effects of AD-MSC therapy showed that OA of the elbow joints improved with time, indicating significant potential for clinical use in the treatment of lameness, particularly when administered before the injury becomes severe.  相似文献   
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