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131.
Eric A Gaucher Logan G Graddy Tang Li Rosalia CM Simmen Frank A Simmen David R Schreiber David A Liberles Christine M Janis Steven A Benner 《BMC biology》2004,2(1):19
Background
Joining a model for the molecular evolution of a protein family to the paleontological and geological records (geobiology), and then to the chemical structures of substrates, products, and protein folds, is emerging as a broad strategy for generating hypotheses concerning function in a post-genomic world. This strategy expands systems biology to a planetary context, necessary for a notion of fitness to underlie (as it must) any discussion of function within a biomolecular system. 相似文献132.
Shui-Lian Yu Paul KS Chan Chun-Kwok Wong Cheuk-Chun Szeto Suzanne C Ho Karine So May MY Yu So-Fan Yim Tak-Hong Cheung Martin CS Wong Jo LK Cheung Apple CM Yeung Edmund K Li Lai-Shan Tam 《Arthritis research & therapy》2012,14(2):R80
IntroductionPrevalence of an abnormal Papanicolaou smear was significantly increased in lupus patients in cross-sectional studies, associated with a higher prevalence of high-risk human papillomavirus (HPV) infection. The nucleic acid-specific Toll-like receptors (TLRs) locate at the endolysosomal compartments and trigger the induction of cytokines for the innate immune response. This study evaluated whether abnormal host innate immune response in lupus patients may enhance HPV persistence.MethodsProtein levels of TLRs 3, 7, 8 and 9 in cervical epithelial cells of lupus patients and controls with or without HPV infection were assessed using flow cytometry. Characteristics associated with the differential expression of TLRs in systemic lupus erythematosus (SLE) were elucidated. The effect and interferon-stimulated genes (ISGs) (ISG15 and Mx-1) gene expressions were then measured in oncogenic HeLa (HPV18), CaSki (HPV) and C33A (HPV negative) cell lines using flow cytometry and quantitative real-time PCR. Ex vivo productions of cytokines and interferon-gamma (IFN-γ) upon TLR ligands stimulations were subsequently measured using cytometric bead array and ELISA.ResultsFor subjects with HPV infection, levels of TLR3 and TLR7 were significantly lower in lupus patients compared with controls. Significantly decreased TLRs 7, 8 and 9 levels were observed in HPV-negative SLE compared to healthy controls. For SLE with and without HPV infection, TLR7 and 9 levels were significantly lower in infected SLE than those in HPV-negative patients. Independent explanatory variables associated with down-regulation of TLR7 level included HPV infection and a higher cumulative dose of prednisolone; while a higher cumulative dose of hydroxychloroquine and HPV infection were associated with down-regulation of TLR9 level. In cervical cell lines, TLRs 3, 7, 8, 9 protein levels and antiviral ISG15 and Mx-1 gene expressions were inhibited in two oncogenic HPV types. Functional data showed that the induction of pro-inflammatory cytokines by TLR ligands (R837, ssRNA and ODN2395) was greatly impaired in CaSki and HeLa than C33A cells.ConclusionsIn conclusion, prednisolone and TLR antagonist (hydroxychloroquine) may down-regulate protein levels of TLR7 and TLR9 in lupus patients, thereby decreasing the innate immune response against HPV infection. Upon infection, HPV further down-regulate TLR7 and 9 levels for viral persistence. Furthermore, reduction of nucleic acid-sensing TLRs 7, 8 and 9 in carcinogenic HPVs ensures that the expression of inducible pro-inflammatory cytokines is minimized to prevent the expression of antiviral ISGs (ISG15 and Mx-1) on a biologically relevant antiviral response. 相似文献
133.
Nikoletta Rovina Andreas Papapetropoulos Androniki Kollintza Makrina Michailidou Davina CM Simoes Charis Roussos Christina Gratziou 《Respiratory research》2007,8(1):53
BackgroundPatients with bronchitis type of chronic obstructive pulmonary disease (COPD) have raised vascular endothelial growth factor (VEGF) levels in induced sputum. This has been associated with the pathogenesis of COPD through apoptotic and oxidative stress mechanisms. Since, chronic airway inflammation is an important pathological feature of COPD mainly initiated by cigarette smoking, aim of this study was to assess smoking as a potential cause of raised airway VEGF levels in bronchitis type COPD and to test the association between VEGF levels in induced sputum and airway inflammation in these patients.Methods14 current smokers with bronchitis type COPD, 17 asymptomatic current smokers with normal spirometry and 16 non-smokers were included in the study. VEGF, IL-8, and TNF-α levels in induced sputum were measured and the correlations between these markers, as well as between VEGF levels and pulmonary function were assessed.ResultsThe median concentrations of VEGF, IL-8, and TNF-α were significantly higher in induced sputum of COPD patients (1,070 pg/ml, 5.6 ng/ml and 50 pg/ml, respectively) compared to nonsmokers (260 pg/ml, 0.73 ng/ml, and 15.4 pg/ml, respectively, p < 0.05) and asymptomatic smokers (421 pg/ml, 1.27 ng/ml, p < 0.05, and 18.6 pg/ml, p > 0.05, respectively). Significant correlations were found between VEGF levels and pack years (r = 0.56, p = 0.046), IL-8 (r = 0.64, p = 0.026) and TNF-α (r = 0.62, p = 0.031) levels both in asymptomatic and COPD smokers (r = 0.66, p = 0.027, r = 0.67, p = 0.023, and r = 0.82, p = 0.002, respectively). No correlation was found between VEGF levels in sputum and pulmonary function parameters.ConclusionVEGF levels are raised in the airways of both asymptomatic and COPD smokers. The close correlation observed between VEGF levels in the airways and markers of airway inflammation in healthy smokers and in smokers with bronchitis type of COPD is suggestive of VEGF as a marker reflecting the inflammatory process that occurs in smoking subjects without alveolar destruction. 相似文献
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135.
Pfefferkorn JA Litchfield J Hutchings R Cheng XM Larsen SD Auerbach B Bush MR Lee C Erasga N Bowles DM Boyles DC Lu G Sekerke C Askew V Hanselman JC Dillon L Lin Z Robertson A Olsen K Boustany C Atkinson K Goosen TC Sahasrabudhe V Chupka J Duignan DB Feng B Scialis R Kimoto E Bi YA Lai Y El-Kattan A Bakker-Arkema R Barclay P Kindt E Le V Mandema JW Milad M Tait BD Kennedy R Trivedi BK Kowala M 《Bioorganic & medicinal chemistry letters》2011,21(9):2725-2731
The design of drugs with selective tissue distribution can be an effective strategy for enhancing efficacy and safety, but understanding the translation of preclinical tissue distribution data to the clinic remains an important challenge. As part of a discovery program to identify next generation liver selective HMG-CoA reductase inhibitors we report the identification of (3R,5R)-7-(4-((3-fluorobenzyl)carbamoyl)-5-cyclopropyl-2-(4-fluorophenyl)-1H-imidazol-1-yl)-3,5-dihydroxyheptanoic acid (26) as a candidate for treating hypercholesterlemia. Clinical evaluation of 26 (PF-03491165), as well as the previously reported 2 (PF-03052334), provided an opportunity for a case study comparison of the preclinical and clinical pharmacokinetics as well as pharmacodynamics of tissue targeted HMG-CoA reductase inhibitors. 相似文献
136.
The whole-cell patch-clamp technique was used to study the properties of inward ionic currents found in primary cultures of rat and mouse skeletal myotubes and in freshly dissociated fibers of the flexor digitorum brevis muscle of rats. In each of these cell types, test depolarizations from the holding potential (-80 or -90 mV) elicited three distinct inward currents: a sodium current (INa) and two calcium currents. INa was the dominant inward current: under physiological conditions, the maximum inward INa was estimated to be at least 30-fold larger than either of the calcium currents. The two calcium currents have been termed Ifast and Islow, corresponding to their relative rates of activation. Ifast was activated by test depolarizations to around -40 mV and above, peaked in 10-20 ms, and decayed to baseline in 50-100 ms. Islow was activated by depolarizations to approximately 0 mV and above, peaked in 50-150 ms, and decayed little during a 200-ms test pulse. Ifast was inactivated by brief, moderate depolarizations; for a 1-s change in holding potential, half-inactivation occurred at -55 to -45 mV and complete inactivation occurred at -40 to -30 mV. Similar changes in holding potential had no effect on Islow. Islow was, however, inactivated by brief, strong depolarizations (e.g., 0 mV for 2 s) or maintained, moderate depolarizations (e.g., -40 mV for 60 s). Substitution of barium for calcium had little effect on the magnitude or time course of either Ifast or Islow. The same substitution shifted the activation curve for Islow approximately 10 mV in the hyperpolarizing direction without affecting the activation of Ifast. At low concentrations (50 microM), cadmium preferentially blocked Islow compared with Ifast, while at high concentrations (1 mM), it blocked both Ifast and Islow completely. The dihydropyridine calcium channel antagonist (+)-PN 200-110 (1 microM) caused a nearly complete block of Islow without affecting Ifast. At a holding potential of -80 mV, the half-maximal blocking concentration (K0.5) for the block of Islow by (+)-PN 200-110 was 182 nM. At depolarized holding potentials that inactivated Islow by 35-65%, K0.5 decreased to 5.5 nM. 相似文献
137.
A mathematical approach was developed to model and optimize selection on multiple known quantitative trait loci (QTL) and polygenic estimated breeding values in order to maximize a weighted sum of responses to selection over multiple generations. The model allows for linkage between QTL with multiple alleles and arbitrary genetic effects, including dominance, epistasis, and gametic imprinting. Gametic phase disequilibrium between the QTL and between the QTL and polygenes is modeled but polygenic variance is assumed constant. Breeding programs with discrete generations, differential selection of males and females and random mating of selected parents are modeled. Polygenic EBV obtained from best linear unbiased prediction models can be accommodated. The problem was formulated as a multiple-stage optimal control problem and an iterative approach was developed for its solution. The method can be used to develop and evaluate optimal strategies for selection on multiple QTL for a wide range of situations and genetic models. 相似文献
138.
139.
Jonathan?CM?Clark Stuart?J?Galloway Stephen?M?Schlicht Ross?PV?McKellar Peter?FM?ChoongEmail author 《International Seminars in Surgical Oncology : ISSO》2009,6(1):15
Myoepitheliomas of the extremity are rare and usually benign, while a minority display malignant features. This case demonstrates the diagnosis and management of myoepithelioma within the carpal tunnel. Clinical and radiological tumour features were evaluated. Hematoxylin and eosin stained tumour sections were examined, and immunohistochemistry was performed. Histology revealed a nodular mass of epithelioid cells in clusters within a myxoid/chondroid stroma. No mitoses were noted. Cytokeratins, neuron-specific enolase, synaptophysin, glial fibrillary acidic protein, and S100 were positive on immunohistochemistry. A literature review revealed very few prior reports of myoepithelioma in the wrist, and limited data concerning any relationship between recurrence and quality of surgical margins. In this case, wide local excision would have significantly compromised dominant hand function, and therefore a marginal excision was deemed appropriate in the context of bland histological features. Surgical margins noted in future case reports will aid clinical decision making. 相似文献
140.
A Geert Heidema Jolanda MA Boer Nico Nagelkerke Edwin CM Mariman Daphne L van der A Edith JM Feskens 《BMC genetics》2006,7(1):1-15