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1.
Total serum protein levels in 70 patients with urolithiasis were not significantly different from those in 20 control subjects, although certain variations were detected in individual protein patterns. In contrast, total urinary protein was significantly higher in patients with urolithiasis. 4-6 different components, i.e., albumin, alpha 1-acidic glycoprotein, alpha 1-antitrypsin, Gc-globulin, fibrinogen and immunoglobulin G, were found in the matrices of calculi and in urine, suggesting that proteinuria may play a role in the formation of stones in patients with urolithiasis.  相似文献   
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Journal of Microbiology - Due to accumulating protein structure information and advances in computational methodologies, it has now become possible to predict protein-compound interactions. In...  相似文献   
4.
Stromal cells with a myofibroblast phenotype present in the normal human esophagus are increased in individuals with gastro-esophageal reflux disease (GERD). We have previously demonstrated that myofibroblasts stimulated with acid and TLR4 agonists increase IL-6 and IL-8 secretion using primary cultures of myofibroblasts established from normal human esophagus. While primary cultures have the advantage of reflecting the in vivo environment, a short life span and unavoidable heterogeneity limits the usefulness of this model in larger scale in vitro cellular signaling studies. The major aim of this paper therefore was to generate a human esophageal myofibroblast line with an extended lifespan. In the work presented here we have generated and characterized an immortalized human esophageal myofibroblast line by transfection with a commercially available GFP-hTERT lentivirus. Immortalized human esophageal myofibroblasts demonstrate phenotypic, genotypic and functional similarity to primary cultures of esophageal myofibroblasts we have previously described. We found that immortalized esophageal myofibroblasts retain myofibroblast spindle-shaped morphology at low and high confluence beyond passage 80, and express α-SMA, vimentin, and CD90 myofibroblast markers. Immortalized human esophageal myofibroblasts also express the putative acid receptor TRPV1 and TLR4 and retain the functional capacity to respond to stimuli encountered in GERD with secretion of IL-6. Finally, immortalized human esophageal myofibroblasts also support the stratified growth of squamous esophageal epithelial cells in 3D organotypic cultures. This newly characterized immortalized human esophageal myofibroblast cell line can be used in future cellular signaling and co-culture studies.  相似文献   
5.
Acinetobacter baumannii is an alarming nosocomial pathogen that is resistant to multiple drugs. The pathogen is forefront of scientific attention because of high mortality and morbidity found for its complications in the past decade. As a consequence, identification of novel drug candidates and subsequent designing of novel chemical scaffolds is an imperative need of time. In the present study, we used a recently reported structure of BfmR enzyme and performed structure based virtual screening, MD simulation and binding free energies calculations. MD simulation revealed a profound movement of the best-characterized inhibitor towards the α4-β5-α5 face of the enzyme receiver domain, thus indicating its high affinity for this site compared to phosphorylation. Furthermore, it was observed that the enzyme and enzyme-inhibitor complex have high structure stability with mean RMSD of 1.2 and 1.1 Å, respectively. Binding free energy calculations for the complex unraveled high stability with MMGBSA score of ?26.21?kcal/mol and MMPBSA score of ?1.47?kcal/mol. Van der Waal energy was found highly favorable with value of ?30.25?kcal/mol and dominated significantly the overall binding energy. Furthermore, a novel WaterSwap assay was used to circumvent the limitations of MMGB/PBSA that complements the inhibitor affinity for enzyme active pocket as depicted by the low convergence of Bennett, TI and FEP algorithms. Results yielded from this study will not only give insight into the phenomena of inhibitor movement towards the enzyme receiver domain, but will also provide a useful baseline for designing derivatives with improved biological and pharmacokinetics profiles.

Communicated by Ramaswamy H. Sarma  相似文献   

6.
Levamisole (LMS), utilized in the adjuvant treatment of patients with stage III colon cancer, is immunomodulatory. To determine whether alterations in immune parameters before, during and after 12 months of 5FU/LMS therapy correlate with disease-free survival, 38 patients enrolled on Southwest Oncology Group (SWOG) protocol 8899 received extensive lymphocyte phenotypic analysis prior to therapy and 3, 6, 12 and 15 months after treatment initiation. The median follow-up of patients is 41 months. Significant increases in the proportion and total number of CD56+ natural killer cells were seen, starting at 3 months and continuing until 15 months (P < 0.001). Increases in the total numbers of cells expressing CD25 (interleukin-2 receptor), VLA4 and the combinations of CD4: CD45RA and CD4:CDw29 were not evident during therapy but were seen at 15 months (P < 0.05: CD25, CD4:CDw29, CD4:CD45RA; P < 0.001: VLA4). Low levels of CD8+ cells prior to treatment initiation and after 3 months of therapy correlated with early relapse within the first year of 5FU/LMS treatment. Patients who have remained disease-free (n = 22, median follow-up 45 months) demonstrated increases in the total numbers of CD8+, CD25+, CD56+, VLA4+, CD4: CDw29 and CD4:CD45RA cells, primarily at 15 months. In contrast, patients who relapsed had decreased numbers of CD8+, CD4:CDw29, CD4: CD45RA and VLA4+ cells and minimal increases in CD56+ and CD25+ cells. Statistically significant differences between the late-relapse group and the group remaining disease-free were seen for CD25+, CD4: CD45RA and CD4:CDw29 cells at the 15-month assay time (P =0.0276, P =0.0349, P =0.0178 respectively). In conclusion, multiple alterations in lymphocyte phenotype, with increases in the proportion and total number of cells involved in cell-mediated immune responses, were seen during and especially following completion of therapy with 5FU/LMS. Many of these changes are significantly associated with clinical outcome and may be useful for risk stratification of stage III colon cancer patients following completion of adjuvant therapy. Received: 9 July 1999 / Accepted: 11 August 1999  相似文献   
7.
The role of integrin and extracellular matrix proteins in various pathological processes (including angiogenesis, thrombosis, apoptosis and cell migration and proliferation), leading to both acute and chronic disease states (e.g. ocular diseases, metastasis, unstable angina, myocardial infarction, stroke, osteoporosis, a wide range of inflammatory diseases, vascular remodeling and neurodegenerative disorders) has been recently documented. A key success in this field is evident from the potential role of the platelet GPIIb/IIIa (alphaIIbbeta3) integrin in the prevention, treatment and perhaps diagnosis of various thromboembolic disorders. Additionally, progress has been shown in the development of leukocyte alpha4beta1 antagonists for various inflammatory indications and alphav integrin antagonists for angiogenesis and vascular-related disorders. However, the exact modes of action of certain integrin antagonists are still not fully clear. Integrin antagonists in clinical or pre-clinical development are expected to be used as a stand-alone therapy or, better, as an adjunct to other pharmacotherapy, radiotherapy or interventional procedures.  相似文献   
8.
We investigated the mechanisms of airway protection and bolus transport during retching and vomiting by recording responses of the pharyngeal, laryngeal, and hyoid muscles and comparing them with responses during swallowing and responses of the gastrointestinal tract. Five dogs were chronically instrumented with electrodes on the striated muscles and strain gauges on smooth muscles. Retching and vomiting were stimulated by apomorphine (5-10 ug/kg iv). During retching, the hyoid and thyroid descending and laryngeal abductor muscles were activated; between retches, the hyoid, thyroid, and pharyngeal elevating, and laryngeal adductor muscles were activated. Vomiting always occurred during the ascending phase of retching and consisted of three sequential phases of hyoid and pharyngeal muscle activation culminating in simultaneous activation of all recorded elevating and descending laryngeal, hyoid, and pharyngeal muscles. Retrograde activation of esophagus and pharyngeal muscles occurred during the later phases, and laryngeal adductor was maximally activated in all phases of the vomit. During swallowing, the laryngeal adductor activation was followed immediately by brief activation of the laryngeal abductor. We concluded that retching functions to mix gastric contents with refluxed intestinal secretions and to impart an orad momentum to the bolus before vomiting. During retches, the airway is protected by glottal closure, and between retches, it is protected by ascent of the larynx and closure of the upper esophageal sphincter. The airway is protected by maximum glottal closure during vomiting. During swallowing, the airway is protected by laryngeal elevation and glottal closure followed by brief opening of the glottis, which may release subglottal pressure expelling material from the laryngeal vestibule.  相似文献   
9.
MicroRNAs are messengers during interferon-virus interplay and are involved in antiviral immunity, however, little is known about interferon-related microRNAs regarding their detection in serum and their potential use as non-invasive diagnostic and prognostic biomarkers in chronic hepatitis C (CHC). To elucidate some of the molecular aspects underlying failure of pegylated interferon-α/ribavirin therapy, we investigated pretreatment expression profiles of seven selected interferon-related microRNAs (miR-146a, miR-34a, miR-130a, miR-19a, miR-192, miR-195, and miR-296) by quantitative RT-PCR custom array technology in serum of Egyptian CHC genotype 4 patients and whether their pretreatment levels would predict patient response to the combination therapy. One hundred and six CHC patients and forty matched healthy controls were included. Patients were divided into sustained virological response (SVR) and non-responder (NR) groups. Serum miR-34a, miR-130a, miR-19a, miR-192, miR-195, and miR-296 were upregulated, whereas serum miR-146a was downregulated in CHC compared to controls. Significant correlations were found between expression levels of studied microRNAs and also with clinical data. Pretreatment levels of miR-34a, miR-130a, and miR-195 were significantly higher, whereas miR-192 and miR-296 levels were significantly lower in SVR than NR patients. miR-19a and miR-146a levels were not significantly different between the two groups. miR-34a was superior to differentiate CHC from controls, whereas miR-296 was superior to discriminate SVR from NR patients by receiver operating characteristic analysis. Multivariate logistic analysis revealed miR-34a and miR-195 as independent predictors for SVR and miR-192 as an independent variable for non-response. In conclusion, pretreatment expression profiles of five interferon-related microRNAs are associated with treatment outcome in CHC. Of these, miR-34a, miR-195, and miR-192 could predict treatment response. The profiling results could be used as novel non-invasive diagnostic and prognostic pharmacogenetic biomarkers for treatment personalization in CHC and could help to identify new microRNA-based antivirals.  相似文献   
10.
The matrix-degrading enzyme aggrecanase has been identified in cartilage and is largely responsible for cartilage breakdown. The present study determined the efficacy of different heparin molecular weight fractions (HMWFs) and low molecular weight heparins (LMWHs) on aggrecanase activity. Aggrecanase activity was determined using biotinylated peptide substrate, which was immobilized onto streptavidin-coated 96-well plates; aggrecanase enzyme was then added. Proteolysis of the substrate at the specific amide bond was detected using specific antibody for the neoepitope generated. HMWFs ranging from 1,700 to 12,000 Da demonstrated a concentration-dependent inhibitory efficacy of aggrecanase activity, with a Ki ranging from 5,000 nM down to 1 nM as a function of the molecular weight. The higher the molecular weight distribution, the greater the inhibitory efficacy of the heparin fragments toward aggrecanase activity. The absence or presence of antithrombin did not alter the affinity of heparin in inhibiting aggrecanase. Additionally, tissue factor pathway inhibitor at various levels did not alter the activity of aggrecanase. LMWHs demonstrated different levels of potency in inhibiting aggrecanase activity as a function of their average molecular weight distribution. Tinzaparin (average molecular weight = 6,500 Da) and enoxaparin (average molecular weight = 4,500 Da) demonstrated a Ki of 20 and 80 nM, respectively. The aggrecanase inhibitory effect of LMWH might contribute to blocking inflammation and tumor invasion by inhibiting aggrecanase activity and maintaining an intact extracellular matrix barrier.  相似文献   
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