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991.
Flávia Regina Souza Lima Nelcy Gonçalves Flávia CarvalhoAlcantara Gomes Marta Sampaio De Freitas Vivaldo Moura Neto 《International journal of developmental neuroscience》1998,16(1):36
Astrocytes are target to triiodothyronine (T3) hormone action during rat braindevelopment. In this work, we show that astrocytes from distinct developing brain regions aredifferently responsive to thyroid hormone. Distinctly from embryonic or newborn cerebralhemisphere and mesencephalic astrocytes, newborn cerebellar and embryonic hippocampalastrocytes do not change their morphology in response to hormone treatment. We also analysedprotein synthesis and secretion from these T3-treated astrocytes. The results showed a significantincrease in protein synthesis in astrocytes from older brain regions. Maximum effect, however,was observed in cerebral hemisphere astrocytes from newborn rats. The protein secretion effectwas also more evident in the cerebral hemisphere as well as in cerebellar astrocytes fromnewborn rats. In addition, we examined T3 effects on GFAP/vimentin expression by culturing6-day old cerebellar astrocytes. In this case T3 seems to induce GFAP expression which might beoccurring as a first step to astrocyte differentiation. 相似文献
992.
Anirudh Bhimavarapu Qiao Deng Marta Bean Nick Lee Thomas R. Ziegler Jessica Alvarez Vin Tangpricha 《The American journal of the medical sciences》2021,361(1):75-82
BackgroundIndividuals with cystic fibrosis (CF) have difficulty maintaining optimal vitamin D status due to pancreatic insufficiency-induced malabsorption, inadequate sunlight exposure, and poor intake of vitamin D containing foods. Vitamin D deficiency may increase the risk of pulmonary exacerbations of CF. The objective of this study was to assess factors impacting vitamin D status in patients with CF recently hospitalized for a pulmonary exacerbation of CF.MethodsThis was a pre-planned analysis of vitamin D intake in patients enrolled in a multi-center, double-blind, randomized controlled study examining vitamin D therapy for pulmonary exacerbation of CF. Demographic information, responses from a habitual sun exposure questionnaire and food frequency questionnaire, and vitamin D supplement usage were queried and compared to serum 25-hydroxyvitamin D (25(OH)D) concentrations.ResultsA total of 48 subjects were included in this analysis. Subjects were taking approximately 1,200 IU of vitamin D daily. Reported vitamin D intake, age, race, employment, and education were not significantly associated with vitamin D status in this population. However, smoking status, sunlight exposure in the last 3 years, and skin type (in the bivariate model) were all significantly associated with vitamin D status (all p<0.05).ConclusionsSunlight exposure was the most predictive determinant of vitamin D status in patients with CF prior to pulmonary exacerbation. Subjects reported vitamin D intake below the recommended amounts. The role and mode of optimizing vitamin D status prior to a pulmonary exacerbation needs further investigation. 相似文献
993.
Fuste V, del Pino M, Perez A, Garcia A, Torne A, Pahisa J & Ordi J(2010) Histopathology 57, 907–916 Primary squamous cell carcinoma of the vagina: human papillomavirus detection, p16 INK4A overexpression and clinicopathological correlations Aim: To determine the role of human papillomavirus (HPV) in the pathogenesis of primary squamous cell carcinoma of the vagina (SCCVa), and to evaluate its clinicopathological significance. Methods and results: All cases of SCCVa diagnosed over a 15‐year period from two hospitals in Barcelona, Spain (n = 32) were retrieved. Patients with a history of carcinoma of the cervix diagnosed <5 years before were excluded. HPV was detected and typed by polymerase chain reaction (PCR) using SPF10 primers. Immunohistochemistry was performed for p16 and p53. HPV was detected in 25 cases (78.1%). HPV16 was the most prevalent type. Patients with HPV‐positive tumours were associated frequently with a history of carcinoma or intraepithelial neoplasia of the cervix or vulva diagnosed more than 5 years before (56% versus 0%; P = 0.01). HPV‐positive tumours were more frequently of non‐keratinizing, basaloid or warty type than HPV‐negative neoplasms (84% versus 14.3%; P < 0.001), and showed diffuse positive immunoreactivity for p16INK4a (96%, versus 14.3%; P < 0.001). The sensitivity and specificity of p16 to identify HPV‐positive tumours were 96% and 85.7%, respectively. Conclusions: A high number of SCCVs are related to HPV infection and may be identified by immunohistochemistry for p16. HPV‐positive tumours tend to affect women with history of cervical neoplasia. 相似文献
994.
The biochemical selectivity of novel COX-2 inhibitors in whole blood assays of COX-isozyme activity 总被引:2,自引:0,他引:2
Tacconelli S Capone ML Sciulli MG Ricciotti E Patrignani P 《Current medical research and opinion》2002,18(8):503-511
We have evaluated the biochemical selectivity of novel cyclo-oxygenase (COX)-2 inhibitors, etoricoxib, valdecoxib, DFU and DFP, vs rofecoxib and celecoxib, using the human whole blood assays of COX-isozyme activity, in vitro. Compounds were incubated with human whole blood samples, allowed to clot for 1 h at 37 degrees C, or stimulated with lipopolysaccharide (10 microg/ml) for 24 h at 37 degrees C. Serum thromboxane (TX) B2 and plasma prostaglandin (PG) E2 levels were measured by specific radioimmunoassays as indices of platelet COX-1 and monocyte COX-2 activity, respectively. Valdecoxib, etoricoxib, DFU and DFP inhibited platelet COX-1 and monocyte COX-2 with the following COX-1/COX-2 IC50 ratios: 61.5, 344, 660 and 1918, respectively. The reference compounds, celecoxib and rofecoxib had corresponding values of 29.6 and 272. In conclusion, a second wave of COX-2 inhibitors with higher biochemical selectivity than the existing coxibs has been developed. Whether their administration will be associated with improved clinical efficacy and/or safety vis-à-vis celecoxib and rofecoxib remains to be established. 相似文献
995.
Marta Rubio Daniele Avitabile Kimberlee Fischer Natalie Gude Shikha Mishra Eric M. Schaefer Mark A. Sussman 《Journal of molecular and cellular cardiology》2009,47(1):96-103
The phosphoinositide 3-kinase (PI3K)/phosphoinositide dependent kinase 1 (PDK1) signaling pathway exerts cardioprotective effects in the myocardium through activation of key proteins including Akt. Activated Akt accumulates in nuclei of cardiomyocytes suggesting that biologically relevant targets are located in that subcellular compartment. Nuclear Akt activity could be potentiated in both intensity and duration by the presence of a nuclear-associated PI3K/PDK1 signaling cascade as has been described in other non-myocyte cell types. PI3K/PDK1 distribution was determined in vitro and in vivo by immunostaining and nuclear extraction of cultured rat neonatal cardiomyocytes or transgenic mouse hearts. Results show that PI3K and PDK1 are present at a basal level in cardiomyocytes nuclei and that cardioprotective stimulation with atrial natriuretic peptide (ANP) increases their nuclear localization. In comparison, overexpression of nuclear-targeted Akt does not mediate increased translocation of either PI3K or PDK1 indicating that accumulation of Akt does not drive PI3K or PDK1 into the nuclear compartment. Furthermore, PI3K and phospho-Akt473 show parallel temporal accumulation in the nucleus following (MI) infarction challenge. These findings demonstrate the presence of a dynamically regulated nuclear-associated signaling cascade involving PI3K and PDK that presumably influences nuclear Akt activation. 相似文献
996.
Filip M Faron-Górecka A Kuśmider M Gołda A Frankowska M Dziedzicka-Wasylewska M 《Brain research》2006,1071(1):218-225
In the present study, we used in situ hybridization to examine the influence of acute or repeated cocaine administrations and withdrawal from repeated cocaine treatment on the level of brain-derived neurotrophic factor (BDNF) and its receptor trkB mRNAs in rat brain. Cocaine (10 mg/kg i.p.) injected acutely produced locomotor hyperactivation, while repeated (single injection for 5 days) administrations of cocaine (10 mg/kg) induced a two-fold increases in the locomotor activity in rats in response to a challenge cocaine dose (10 mg/kg) on day 10, as compared to the saline-treated animals (sensitization). Cocaine treatments induced a brain-region-specific decrease in the levels of trkB mRNA. On the other hand, BDNF mRNA in the rat hippocampus was increased only in the group of rats subjected to cocaine withdrawal. Animals under cocaine withdrawal demonstrated a significant increase in the immobility time measured by the use of modified forced swimming test. Therefore, the increases in the levels of BDNF mRNA in the rat hippocampus seem to be correlated with "depressive-like" behavioral effects during withdrawal from repeated cocaine treatment. In the shell (but not in the core) of the nucleus accumbens, the levels of BDNF mRNA were significantly increased following acute and repeated cocaine treatment as well as during cocaine withdrawal, which indicates that the alterations in the neurotrophin level in the brain region important for the expression of cocaine-induced sensitization involve other mechanisms. 相似文献
997.
Toro C Jiménez V Rodríguez C Del Romero J Rodés B Holguín A Alvarez P García-Campello M Gómez-Hernando C Guelar A Sheldon J de Mendoza C Simón A Soriano V 《Journal of medical virology》2006,78(12):1599-1608
The increased immigration from developing regions to Western countries raises public health concerns related to blood-borne viruses. The prevalence of human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), and human T-lymphotropic virus (HTLV) infections among recent immigrants attending several Spanish diagnostic centers in years 2002 and 2003 was examined. Genetic characterization of viral subtypes and its relationship with distinct at-risk populations was carried out. A total of 1,303 immigrants were identified. They originated in Latin America (46.9%), Sub-Saharan Africa (23.7%), Eastern Europe (9.4%), and the Maghreb (9.2%). Seroprevalence rates were as follows: HIV-1 4.2%, HBV 4.1%, HCV 2.9%, and HTLV-1 0.8%. All patients with HIV-1 non-B subtypes, HBV genotypes E and A3, and HCV genotype 4 were sub-Saharan Africans, and had been infected mainly through heterosexual contacts. In contrast, Latin American homo/bisexual men carried HIV-1 subtype B most likely acquired after their arrival to Spain. In conclusion, while Sub-Saharan Africans carry wide diverse genetic variants of blood-borne viruses, the absence of high-risk practices in most cases could limit the spread of these variants. In contrast, Latin Americans with high-risk sexual practices may be a particularly vulnerable collective to acquire blood-borne viruses in the receptor country. 相似文献
998.
Rita Faria Marta O. Soares Eldon Spackman Hashim U. Ahmed Louise C. Brown Richard Kaplan Mark Emberton Mark J. Sculpher 《European urology》2018,73(1):23-30
Background
The current recommendation of using transrectal ultrasound-guided biopsy (TRUSB) to diagnose prostate cancer misses clinically significant (CS) cancers. More sensitive biopsies (eg, template prostate mapping biopsy [TPMB]) are too resource intensive for routine use, and there is little evidence on multiparametric magnetic resonance imaging (MPMRI).Objective
To identify the most effective and cost-effective way of using these tests to detect CS prostate cancer.Design, setting, and participants
Cost-effectiveness modelling of health outcomes and costs of men referred to secondary care with a suspicion of prostate cancer prior to any biopsy in the UK National Health Service using information from the diagnostic Prostate MR Imaging Study (PROMIS).Intervention
Combinations of MPMRI, TRUSB, and TPMB, using different definitions and diagnostic cut-offs for CS cancer.Outcome measurements and statistical analysis
Strategies that detect the most CS cancers given testing costs, and incremental cost-effectiveness ratios (ICERs) in quality-adjusted life years (QALYs) given long-term costs.Results and limitations
The use of MPMRI first and then up to two MRI-targeted TRUSBs detects more CS cancers per pound spent than a strategy using TRUSB first (sensitivity = 0.95 [95% confidence interval {CI} 0.92–0.98] vs 0.91 [95% CI 0.86–0.94]) and is cost effective (ICER = £7,076 [€8350/QALY gained]). The limitations stem from the evidence base in the accuracy of MRI-targeted biopsy and the long-term outcomes of men with CS prostate cancer.Conclusions
An MPMRI-first strategy is effective and cost effective for the diagnosis of CS prostate cancer. These findings are sensitive to the test costs, sensitivity of MRI-targeted TRUSB, and long-term outcomes of men with cancer, which warrant more empirical research. This analysis can inform the development of clinical guidelines.Patient summary
We found that, under certain assumptions, the use of multiparametric magnetic resonance imaging first and then up to two transrectal ultrasound-guided biopsy is better than the current clinical standard and is good value for money. 相似文献999.
Matching the evaluation of the clinical efficacy of clopidogrel to platelet function tests relevant to the biological properties of the drug 总被引:6,自引:0,他引:6
Labarthe B Théroux P Angioï M Ghitescu M 《Journal of the American College of Cardiology》2005,46(4):638-645
OBJECTIVES: This study aimed to explore platelet function tests relevant to the biological effects of clopidogrel that could help the clinical monitoring of drug efficacy. BACKGROUND: Clopidogrel selectively inhibits the P2Y12 receptor, the major role of which is stabilization of aggregation, whereas initiation of aggregation depends on activity of both P2Y1 and P2Y12 receptors. METHODS: Tests used were peak aggregation (Agg(max)) and late aggregation (Agg(6min)), and disaggregation, relating to P2Y1 and P2Y12 activity, respectively; and monoclonal antibody binding activated glycoprotein (GP) IIb/IIIa receptors (PAC-1) and P-selectin, measuring activation and secretion. A first study compared hirudin/PPACK (r-hirudin and D-phenylalanyl-prolyl-arginine chloromethyl ketone) with citrate as blood anticoagulant (16 patients), and a second control study compared the effects of clopidogrel, aspirin, or both (20 normal controls). RESULTS: Clopidogrel similarly inhibited adenosine 5'-diphosphate (ADP)-induced Agg(max) with either anticoagulant, but significantly more Agg(6min) (75% vs. 31%), P-selectin (72% vs. 53%), and PAC-1 (62% vs. 24%) in hirudin/PPACK. In the control study, it inhibited Agg(max) by 22%, and Agg(6min), P-selectin, and PAC-1, by 69%, 66%, and 55%, respectively (all p < 0.05). Disaggregation at six min reached 62% with clopidogrel, but was virtually absent with placebo and aspirin. Non-responsiveness as evaluated by inhibition of Agg(max) in citrate was diagnosed in 35% of patients; in half this rate by Agg(6min), P-selectin, and PAC-1; and in 6% to 12% with the latter tests performed in hirudin/PPACK. CONCLUSIONS: The evaluation of clopidogrel responsiveness by platelet function tests is largely influenced by the choice of blood preservative and functional tests. Measures of aggregation stabilization, and of consequent secretion and activation, identified most patients as responders, contrasting with measures of peak aggregation, by likely reflecting better the interactions clopidogrel and the P2Y12 receptor. 相似文献
1000.
Marta Manovel López Miguel Maldonado López Isabel de la Torre Díez José Carlos Pastor Jimeno Miguel López-Coronado 《Journal of medical systems》2017,41(5):81
Decision support systems (DSS) are increasingly demanded due that diagnosis is one of the main activities that physicians accomplish every day. This fact seems critical when primary care physicians deal with uncommon problems belonging to specialized areas. The main objective of this paper is the development and user evaluation of a mobile DSS for iOS named OphthalDSS. This app has as purpose helping in anterior segment ocular diseases’ diagnosis, besides offering educative content about ophthalmic diseases to users. For the deployment of this work, firstly it has been used the Apple IDE, Xcode, to develop the OphthalDSS mobile application using Objective-C as programming language. The core of the decision support system implemented by OphthalDSS is a decision tree developed by expert ophthalmologists. In order to evaluate the Quality of Experience (QoE) of primary care physicians after having tried the OphthalDSS app, a written inquiry based on the Likert scale was used. A total of 50 physicians answered to it, after trying the app during 1 month in their medical consultation. OphthalDSS is capable of helping to make diagnoses of diseases related to the anterior segment of the eye. Other features of OphthalDSS are a guide of each disease and an educational section. A 70% of the physicians answered in the survey that OphthalDSS performs in the way that they expected, and a 95% assures their trust in the reliability of the clinical information. Moreover, a 75% of them think that the decision system has a proper performance. Most of the primary care physicians agree with that OphthalDSS does the function that they expected, it is a user-friendly and the contents and structure are adequate. We can conclude that OphthalDSS is a practical tool but physicians require extra content that makes it a really useful one. 相似文献