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71.
Uzuner N Kavukçu S Yilmaz O Ozkal S Işlekel H Karaman O Soylu A Kargi A 《Acta medica Okayama》2002,56(6):295-301
Leukotrienes, one of the mediators of inflammation in asthma, have a strong bronchoconstrictive effect. L-carnitine has been reported to influence respiratory functions. It has also been reported that L-carnitine inhibits leukotriene synthesis. To evaluate the effects of L-carnitine on oxygen saturation, urine leukotriene E4 levels and lung histopathology in a murine model of asthma, high IgE responder BALB/c mice (n = 24) were systemically sensitized to ovalbumin and chronically challenged with low particle mass concentrations of aerosolized ovalbumin, and then they were divided into 3 groups (study groups A, B, and C) each including eight mice. After methacholine-induced bronchoconstriction, the mice in groups A and B were given intraperitoneal L-carnitine (250 and 125 mg/kg, respectively), while the mice in group C were given placebo. Oxygen saturation of the mice was measured by pulse oxymeter before and after methacholine and after L-carnitine/ placebo application. In addition, urine leukotriene E4 levels were measured before asthma development, and 24-h after L-carnitine injection in asthmatic mice. Inflammation in the lung tissues of the sacrificed animals was scored histopathologically to determine the effect of L-carnitine on tissue level. A control group of non-sensitized mice (n = 8) treated with placebo only was used for comparison of urine leukotriene E4 levels and of histopathological parameters. Oxygen saturation of the mice in the study groups tended to decrease after methacholine and to improve after L-carnitine injection, although these changes were not significant at all time points. Urine leukotriene E4 levels of all 3 study groups increased significantly after asthma development. The rate of increment was smallest in the group given the highest L-carnitine dose (group A). Inflammation at the tissue level was also mildest in group A, and severest in the group that was not given carnitine (group C). All of the study groups and the control group differed significantly with respect to inflammation scores. In conclusion, L-carnitine improved oxygen saturation, and decreased urine leukotriene E4 levels and inflammation in lung tissues in the present murine model of asthma. 相似文献
72.
Determination of theophylline and ephedrine HCL in tablets by ratio-spectra derivative spectrophotometry and LC 总被引:1,自引:0,他引:1
Sentürk Z Erk N Ozkan SA Akay C Cevheroğlu S 《Journal of pharmaceutical and biomedical analysis》2002,29(1-2):291-298
Two methods are described for the determination of theophylline (THP) and ephedrine hydrochloride (EPH) in combined pharmaceutical tablet forms. The first method depends on the use of the first derivative of the ratio-spectra obtained by dividing the absorption spectrum of binary mixtures by a standard spectrum of one of the compounds. The first derivative amplitudes at 231.8 and 250.3 nm were selected for the assay of THP and EPH, respectively. Calibration graphs were established for 20-180 microg ml(-1) for THP and 10-50 microg ml(-1) for EPH. The second method is based on high-performance liquid chromatography on a reversed-phase column using a mobile phase of methanol-water (40+60,v/v) (pH 3) with detection at 217 nm. Linearity was obtained in the concentration range of 5-150 microg ml(-1) for THP and 15-75 microg ml(-1) for EPH. The detection limits for THP and EPH were 0.73 and 0.92 microg ml(-1) by ratio-spectra derivative spectrophotometry and 0.59 and 0.86 microg ml(-1) by HPLC, respectively. The proposed methods were successfully applied to the determination of these drugs in laboratory-prepared mixtures and in tablets. The relative standard deviations were found to be less than 1.5%, indicating reasonable repeatibility of both methods. 相似文献
73.
Nevin de Korompay Mohammed Alshammari Darren Klass Frank Y. Chou John Chung Stephen Ho David M. Liu 《Journal of vascular and interventional radiology : JVIR》2018,29(7):928-935
Purpose
To evaluate cone-beam parenchymal blood volume (PBV) before and after embolization as a predictor of radiographic response to transarterial chemoembolization in unresectable hepatocellular carcinoma (HCC).Materials and Methods
A phase IIa prospective clinical trial was conducted in patients with HCCs > 1.5 cm undergoing chemoembolization; 52 tumors in 40 patients with Barcelona Clinic Liver Criteria stage B disease met inclusion criteria. Pre- and postembolization PBV analysis was performed with a semiquantitative best-fit methodology for index tumors, with a predefined primary endpoint of radiographic response at 3 months. Analyses were conducted with Wilcoxon signed-rank tests and one-way analysis of variance on ranks.Results
Mean tumoral PBV measurements before and after embolization were 170 mL/1,000 mL ± 120 and 0 mL/100 mL ± 130, respectively. Per modified Response Evaluation Criteria In Solid Tumors, 25 tumors (48%) exhibited complete response (CR), 13 (25%) partial response (PR), 3 (6%) stable disease (SD), and 11 (21%) progressive disease (PD). Statistically significant changes in median PBV (ΔPBV) were identified in the CR (P = .001) and PR (P = .003) groups, with no significant difference observed in SD (P = .30) and PD groups (P = .06). A statistically significant correlation between ΔPBV and tumor response was established by one-way analysis of variance on ranks (P = .036; CR, 200 mL/100 mL ± 99; PR, 240 mL/100 mL ± 370; SD, 64 mL/100 mL ± 99; PD, 88 mL/100 mL ± 129).Conclusions
Intraprocedural PBV can be used as a predictor of response in index HCC tumors of > 1.5 cm. 相似文献74.
Deborah A. Witherden Wayne G. Kimpton Nevin J. Abernethy Ross N. P. Cahill 《European journal of immunology》1994,24(10):2329-2336
The thymus plays an essential role in the generation and selection of T cells and exports approximately 0.5–1% of thymocytes per day in young animals and considerably fewer in older animals. To date there have been no studies directly examining fetal thymic export in any species. Using the technique of intrathymic injection of fluorescein isothiocyanate, followed by an assay for green fluorescent cells in the periphery and for the expression of cell surface antigens on these cells, we have compared directly the export of T cells from the fetal and postnatal ovine thymus. While the thymus exports both αβ and γδ T cells, our results demonstrate that the proportion of thymic γδ T cells that are exported per day is much higher than that of thymic αβ T cells. Moreover, the export rate of γδ T cells increased from approximately 1 in every 60 γδ thymocytes per day emigrating from the fetal thymus to 1 in every 20 from the postnatal thymus. In addition, we identify a population of CD5+CD4?CD8?γδ? T cells emigrating from the fetal thymus but greatly reduced among thymic emigrants after birth. These findings have several implications regarding the mechanisms and control of selection of both γδ and αβ T cells. 相似文献
75.
Rick Nevin 《Environmental research》2009,109(3):301-259
This study shows that 1936-1990 preschool blood lead trends explain 65% of the 1948-2001 variation in USA mental retardation (MR) prevalence, 45% of the 1953-2003 variation in the average scholastic achievement test (SAT) verbal score, and 65% of the 1953-2003 variation in the average SAT math score. These temporal relationships are characterized by best-fit time lags (highest R2 and t-value for blood lead) consistent with lead-induced cognitive damage in the first year of life: a 12-year lag for school-age MR, and a 17-year lag for SAT scores. Recent shifts in age-specific MR prevalence are consistent with recent trends in preschool blood lead. SAT and MR trends by race are consistent with racial differences in how 1960s slum clearance affected childhood exposure to severe lead paint hazards. SAT trends by Hispanic origin are consistent with an especially sharp fall in preschool blood lead in New York City since 1970. 相似文献
76.
Abstract: We describe a father and his daughter with keratosis pilaris atrophicans facei, ulerythema ophryogenes, and hereditary woolly hair, an association that has been described only once in the literature. 相似文献
77.
Donald H Beezhold Brett J Green Francoise M Blachere Detlef Schmechel David N Weissman Deborah Velickoff Mary Beth Hogan Nevin W Wilson 《Allergy and asthma proceedings》2008,29(1):29-34
Exposure to indoor fungi is of growing concern in residential and occupational environments in the United States. The purpose of this study was to determine the prevalence of sensitization to common indoor fungal species in an atopic population. We evaluated 102 patients (73 female and 29 male patients) for immunoglobulin E (IgE) reactivity to a panel of skin-prick test (SPT) reagents used for routine allergy testing. Patients also were tested for six additional fungi that are common indoor contaminants. All patients had symptoms consistent with allergic rhinitis or asthma. The presence of specific IgE against the fungal species was determined using immunoblotting. Of the 102 eligible patients, 68% had at least one positive skin test. The most prevalent positive SPTs were to dust mites, cats, vernal grass, and short ragweed. Overall, 21/102 (21%) patients with asthma or allergic rhinitis were skin test positive to at least one fungal extract. Of the patients with a positive SPT to fungi, 12/21 (58%) showed sensitivity to one or more of the newly tested species; most notably Trichoderma viride (8%), Chaetomium globosum (7%), Paecilomyces variotii (7%), and Acremonium strictum (6%). Immunoblotting revealed specific IgE against a number of protein bands belonging to these fungal species. The prevalence of fungal sensitization was common, particularly for indoor fungal contaminants that are not routinely included in SPT panels. Cross-reactivity with other fungi may partially explain our results; however, skin testing for these indoor fungi may provide useful diagnostic information. 相似文献
78.
Ihsan Yigit Metin Atescelik Mustafa Yilmaz Mehmet Cagri Goktekin Mehtap Gurger Nevin Ilhan 《The American journal of emergency medicine》2017,35(12):1895-1898
Objective
We aimed to determine the levels of ubiquitin C-terminal hydrolase-L1 (UCH-L1) in patients admitted to the emergency department with impaired consciousness due to metabolic or neurological reasons.Materials – methods
The study included 80 patients with ischemic stroke (IS), 40 patients with intracranial hemorrhage (ICH), 80 patients with metabolic disorder induced impaired consciousness (MDIC) and 40 healthy controls.Results
The levels of UCH-L1 [median (IQR)] were as follows: 5.59 ng/mL (3.90–9.37) in IS, 5.44 ng/ml (4.01–13.98) in ICH, 3.34 ng/ml (2.29–5.88) in MDIC and 3.94 ng/ml (3.31–7.95) in healthy volunteers. Significantly higher levels were detected in IS and ICH than in MDIC and healthy volunteers. In ROC curve analysis, we detected 63.75% sensitivity and 62.5% specificity (AUC = 0.626, p < 0.0199, 95% CI: 0.533–0.713) with a cutoff value of 4.336 ng/ml for IS and 75% sensitivity and 55% specificity (AUC = 0.664, p < 0.0071, 95% CI: 0.549–0.766) with a cut-off value of 4.036 ng/ml for ICH. However, the sensitivity and specificity for MDIC was 36.25% and 77.5%, respectively, with a cut-off value of 3.256 ng/ml (AUC = 0.525, p = 0.6521, 95% CI: 0.432–0.617). UCH-L1 levels were found to increase significantly with increasing time between the onset of symptoms and blood sampling (r = 0.345, p < 0.001). However, no correlation was found between UCH-L1 levels and age (r = 0.014, p = 0.833), GCS (r = ? 0.115, p = 0.074), mRS (r = 0.063, p = 0.475) and NIHSS (r = 0.056, p = 0.520).Conclusion
In this study, we detected significantly higher levels of UCH-L1 in patients with IS and ICH compared to patients with MDIC and healthy volunteers. 相似文献79.
A J Atkinson W K Lee M L Quinn W Kushner M J Nevin J M Strong 《Clinical pharmacology and therapeutics》1977,21(5):575-587
Ten patients with chronic premature ventricular contractions (PVCs) received short-term oral therapy with N-acetylprocainamide (NAPA) to determine its antiarrhythmic efficacy and side effects under the conditions of a placebo-controlled, dose-ranging trial. NAPA was effective in suppressing PVCs in 8 patients but caused a paradoxical increase in PVC frequency in one. Results were equivocal in the remaining patient because PVCs did not recur when NAPA therapy was withdrawn. Mean NAPA plasma levels as high as 41.1 microng/ml did not have untoward hypotensive or myocardial depressant effects, as judged by electrocardiographic and systolic time intervals. There was, in fact, a consistent reduction in PEP/LVET ratio, indicating that NAPA increases the force of myocardial contraction. The mean NAPA elimination half-life of 10.9 hr was longer than the 6.2 hr half-life reported for normal subjects, but its prolongation was predictably correlated with reductions in creatinine clearance. Gastrointestinal side effects experienced by 3 patients and insomnia noted by 2 patients are similar to known adverse reactions to procainamide. 相似文献
80.
Mehmet Özbek Mustafa Hitit Nuh Yıldırım Özge Özgenç Emel Ergün Levent Ergün Feyzullah Beyaz Nevin Kurtdede Hikmet Altunay 《Acta histochemica》2018,120(8):814-827
Galectins are a family of lectins-binding beta-galactosides involved in a variety of extracellular and intracellular processes, thereby contributing to homeostasis, cell adhesion, cellular turnover, and immunity. This study aimed to determine the localization and expression of galectin-1 (Gal-1) and galectin-3 (Gal-3) in the testis and epididymis of rats at postnatal [(prepubertal (day 5), pubertal (day 20), postpubertal (day 50) and mature (day 70)] periods by using immunohistochemistry and Western blotting. Gal-1 and Gal-3 were differentially expressed in different types of cells in the testis and epididymis during postnatal development. While we detected Gal-1 expression in some spermatogenic cells and Leydig cells in the testis, not in the epididymal epithelium, Gal-3 was expressed in Sertoli cells, peritubular myoid cells, Leydig cells, smooth muscles and interstitial CD68-positive macrophages. Epithelial cells of the corpus and cauda epididymis showed an intense Gal-3 expression. Gal-1 expression was higher in the testis than in the epididymis on days 50 and 70. The expression of Gal-3 in the testis increased from the prepubertal to mature period. While the expression difference of Gal-3 was not statistically significant in the testis and epididymis until puberty, Gal-3 expression in the postpubertal and mature periods was higher in the epididymis. The expression of Gal-3 in the corpus and cauda epididymis was higher than that in the caput epididymis. In conclusion, our findings suggest that puberty has potential regulatory effect on the expression of galectins in testis and epididymis of rats. Gal-1 and 3 may play a role in the development of the reproductive system and the preservation of the immune-privileged environment in the testis, due to their pro-apoptotic and anti-apoptotic functions. The presence of intense expression of Gal-3 in the corpus and cauda epididymis may contribute to the maturation and storage of spermatozoa. 相似文献