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941.
942.
Severe asthma manifests as airway remodeling and irreversible airway obstruction, in part because of the proliferation and migration of human airway smooth muscle (HASM) cells. We previously reported that cyclic adenosine monophosphate-mobilizing agents, including β(2)-adrenergic receptor (β(2)AR) agonists, which are mainstay of asthma therapy, and prostaglandin E2 (PGE2), inhibit the migration of HASM cells, although the mechanism for this migration remains unknown. Vasodilator-stimulated phosphoprotein (VASP), an anticapping protein, modulates the formation of actin stress fibers during cell motility, and is negatively regulated by protein kinase A (PKA)-specific inhibitory phosphorylation at serine 157 (Ser157). Here, we show that treatment with β(2)AR agonists and PGE2 induces the PKA-dependent phosphorylation of VASP and inhibits the migration of HASM cells. The stable expression of PKA inhibitory peptide and the small interfering (si) RNA-induced depletion of VASP abolish the inhibitory effects of albuterol and PGE2 on the migration of HASM cells. Importantly, prolonged treatment with albuterol prevents the agonist-induced phosphorylation of VASP at Ser157, and reverses the inhibitory effects of albuterol and formoterol, but not PGE2, on the basal and PDGF-induced migration of HASM cells. Collectively, our data demonstrate that β(2)AR agonists selectively inhibit the migration of HASM cells via a β(2)AR/PKA/VASP signaling pathway, and that prolonged treatment with albuterol abolishes the inhibitory effect of β-agonists on the phosphorylation of VASP and migration of HASM cells because of β(2)AR desensitization.  相似文献   
943.
MotivationGenetic factors determine differences in pharmacokinetics, drug efficacy, and drug responses between individuals and sub-populations. Wrong dosages of drugs can lead to severe adverse drug reactions in individuals whose drug metabolism drastically differs from the “assumed average”. Databases such as PharmGKB are excellent sources of pharmacogenetic information on enzymes, genetic variants, and drug response affected by changes in enzymatic activity. Here, we seek to aid researchers, database curators, and clinicians in their search for relevant information by automatically extracting these data from literature.ApproachWe automatically populate a repository of information on genetic variants, relations to drugs, occurrence in sub-populations, and associations with disease. We mine textual data from PubMed abstracts to discover such genotype–phenotype associations, focusing on SNPs that can be associated with variations in drug response. The overall repository covers relations found between genes, variants, alleles, drugs, diseases, adverse drug reactions, populations, and allele frequencies. We cross-reference these data to EntrezGene, PharmGKB, PubChem, and others.ResultsThe performance regarding entity recognition and relation extraction yields a precision of 90–92% for the major entity types (gene, drug, disease), and 76–84% for relations involving these types. Comparison of our repository to PharmGKB reveals a coverage of 93% of gene–drug associations in PharmGKB and 97% of the gene–variant mappings based on 180,000 PubMed abstracts.Availabilityhttp://bioai4core.fulton.asu.edu/snpshot.  相似文献   
944.
945.
946.
Experiments on rats with myocardium infarction showed that intravenous administration of etoxidol in a dose of 14.2 mg/kg restricted the size of necrosis area and reduced the ratio of necrosis/ischemia zones. The test compound reduced the risk of rhythm and conduction disturbances induced by administration of toxic epinephrine doses to the mice, and increased mouse survival. Etoxidol administered intravenously to cats with acute myocardial ischemia reduced epinephrine concentration and intensity of free radical oxidation in zones of myocardial lesions against the background of the increase in norepinephrine concentration and antioxidant activity in the myocardium. By antiischemic and antioxidant activity, etoxidol was superior to its structural analogue mexidol.  相似文献   
947.
The TCR repertoire is a mirror of the human immune system that reflects processes caused by infections, cancer, autoimmunity, and aging. Next generation sequencing (NGS) is becoming a powerful tool for deep TCR profiling; yet, questions abound regarding the methodological approaches for sample preparation and correct data interpretation. Accumulated PCR and sequencing errors along with library preparation bottlenecks and uneven PCR efficiencies lead to information loss, biased quantification, and generation of huge artificial TCR diversity. Here, we compare Illumina, 454, and Ion Torrent platforms for individual TCR profiling, evaluate the rate and character of errors, and propose advanced platform‐specific algorithms to correct massive sequencing data. These developments are applicable to a wide variety of next generation sequencing applications. We demonstrate that advanced correction allows the removal of the majority of artificial TCR diversity with concomitant rescue of most of the sequencing information. Thus, this correction enhances the accuracy of clonotype identification and quantification as well as overall TCR diversity measurements.  相似文献   
948.
We analyzed the clinicopathologic features of 10 cases of vulvovaginal myofibroblastoma to widen its morphological and immunohistochemical spectrum. Most tumors (8/10 cases) were located in the vagina. The patients' age ranged from 44 to 77 years, and tumor size ranged from 0.4 to 3 cm. Histologically, 5 tumors had the characteristics of vulvovaginal myofibroblastoma. In addition, we identified 3 cases composed of spindle-shaped cells arranged in short fascicles with intervening thick collagen bands, closely reminiscent of mammary myofibroblastoma. Notably, 1 case resembled Sertoli cell tumor, sclerosing type, because of its predominant cord-like arrangement. In another case, there were highly cellular areas composed of uniform-packed, rounded cells that, at low magnification, looked like a malignant "small round blue cell tumor." A variably thick band of native connective tissue separated tumors from the overlying squamous epithelium even if, in 3 cases, tumor cells extended up to the epithelium. In 7 cases, a variable number of vessels showed perivascular hyalinization. Only rare mitotic figures were identified. All tumors were diffusely positive for vimentin, desmin, and CD99. A variable staining intensity was observed for CD34, Bcl-2, B-cell lymphoma 2 (Bcl-2) CD10, estrogen receptor, and progesterone receptor in most cases, but none expressed α-smooth muscle actin. We emphasize that vulvovaginal myofibroblastoma encompasses a morphological spectrum wider than previously described. The overlapping morphological and immunohistochemical features of vulvovaginal and mammary myofibroblastomas led us to speculate that these are related entities with morphological variations on a common basic theme likely dependent on anatomical location.  相似文献   
949.
ABSTRACT:: Two unusual Carney complex patients are described. In one of them, several cutaneous biopsies revealed myxoid lesions that were rather more close to authentic adnexal neoplasms with myxoid stroma than to a "myxoma with an epithelial component." These included lesions resembling trichofolliculoma, infundibular cyst, and trichodiscoma. Additionally, 1 soft tissue myxoma was unique in the sense that it greatly resembled a cardiac myxoma, begging the question whether this could represent an embolus from the patient's cardiac myxoma. Given the large size and complexity and heterogeneity of the cutaneous lesions, the authors suggest that these may represent authentic cutaneous neoplasms accompanied by myxoid stroma and not adnexal elements induced by the stroma. However, the latter mechanism is well recognized and demonstrated by our second patient in whom adnexal-type elements in the cutaneous lesion were clearly induced by the myxoid stroma but were unusually complex by manifesting panfollicular and also sebaceous differentiation.  相似文献   
950.
ABSTRACT:: The authors report on a case of panfolliculoma with sebaceous differentiation occurring on the scalp of a 53-year-old white man and discuss the pertinent literature.  相似文献   
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