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71.
Mueller Ruediger B. Schulze-Koops Hendrik Furst Daniel E. Cohen Stanley B. Kwok Kenneth Wang Lisy Killeen Tim von Kempis Johannes 《Clinical rheumatology》2022,41(4):1045-1055
Clinical Rheumatology - We assess the impact of switching versus staying on the same tofacitinib dose on efficacy and safety in patients with rheumatoid arthritis (RA). ORAL Sequel was an... 相似文献
72.
Lam TH Stewart SM Ho SY Lai MK Mak KH Chau KV Rao U Salili F 《Addiction (Abingdon, England)》2005,100(7):1003-1011
AIMS: To examine associations among depressive symptoms, smoking, smoking trajectories and quitting smoking in Hong Kong. DESIGN: Prospective longitudinal design, with wave 1 at baseline (T1) and wave 2 (T2) 12 months later. SETTING AND PARTICIPANTS: Form 1 (equivalent to 7th grade in the United States) students, mean age = 12.7 years, n = 1894. MEASUREMENTS: Self-reported smoking status, attempts to quit and depressive symptoms. FINDINGS: At both waves, current as well as ex-smokers had higher depressive symptoms than never smokers. T1 smoking predicted T2 depressive symptoms among those with low baseline depressive symptoms. Depressive symptoms at T1 predicted smoking at T2 among non-smokers at T1. Trajectories were defined by separating participants who were never smokers at both waves ('non-smokers'), those who smoked at both waves ('persistent smokers'), those who smoked at one time but were not smoking at either wave ('past smokers), and those who had never smoked at T1 but reported smoking a year later ('new smokers'). Persistent, past and new smokers had higher depressive symptoms at both waves than non-smokers. Smokers who reported not wanting or trying to quit and those who had been unsuccessful at quitting had higher depressive symptoms at T2 than those who successfully quit. CONCLUSION: Our results suggest that depressive symptoms promote tobacco use in Asian adolescents by making it more likely that an adolescent will begin smoking and less likely that she or he will quit. These findings elucidate risk factors in Hong Kong for two important public health concerns for adolescents: smoking and depression. 相似文献
73.
Yu Koon Chiu Chun Tat Lui Kwok Leung Tsui 《The American journal of emergency medicine》2018,36(1):79-83
Objective
To investigate the relationship between hypotension in the first 3 h after return of spontaneous circulation (ROSC) in patients with out-of-hospital cardiac arrest.Method
This retrospective cohort study occurred at two regional hospitals and included adult OHCA patients who experienced ROSC from July 1, 2014 to December 31, 2015. Hemodynamic and inotrope administration data were retrieved for 3 h after ROSC. We calculated the hypotensive exposure index (HEI) as the surrogate marker of the exposure of hypotension. The area under the ROC curve and multivariate logistic regression models were performed to analyze the effect of HEI on survival. Mean arterial pressure (MAP) was explored in the surviving and non-surviving patient groups using repeated measures MANCOVA, adjusted for the use of inotropes and down time.Results
A total of 289 patients were included in the study, and 29 survived. The median 1-hour HEI and 3-hour HEI were significantly lower in the survival group (p < 0.001). The area under the ROC curve for 3-hour HEI was 0.861. The repeated measures MANCOVA indicated that an interaction existed between post-ROSC time and downtime [F(5,197) = 2.31, p = 0.046]. No significant change in the MAP was observed in the 3 h after ROSC, except in the group with a prolonged down time. According to the tests examining the effects of the use of inotropes on the survival outcomes of the different subjects, the MAP was significantly higher in the surviving group [F(1,201) = 4.11; p = 0.044; ηp2 = 0.020].Conclusion
Among the patients who experienced ROSC after OHCA, post-ROSC hypotension was an independent predictor of survival. 相似文献74.
Kwok Benjamin Brosnahan Shari B. Amoroso Nancy E. Goldenberg Ronald M. Heyman Brooke Horowitz James M. Jamin Catherine Sista Akhilesh K. Smith Deane E. Yuriditsky Eugene Maldonado Thomas S. 《Journal of thrombosis and thrombolysis》2021,51(2):330-338
Journal of Thrombosis and Thrombolysis - Coronavirus disease 2019 (COVID-19) is associated with increased rates of deep vein thrombosis (DVT) and pulmonary embolism (PE). Pulmonary Embolism... 相似文献
75.
Circulating anti-pericyte autoantibodies are present in Type 2 diabetic patients and are associated with non-proliferative retinopathy 总被引:1,自引:0,他引:1
Nayak RC Agardh CD Kwok MG Stjernquist H Farthing-Nayak PJ Agardh E 《Diabetologia》2003,46(4):511-513
AIMS/HYPOTHESIS: This study aims to determine the prevalence of anti-pericyte autoantibodies in Type 2 diabetes and to characterize these autoantibodies as new markers of disease activity in diabetic retinopathy. METHODS: A total of 299 patients with Type 2 diabetes participated in this study. Retinopathy was assessed by 7-field stereo fundus photography and was graded according to the ETDRS scale. Serum anti-pericyte autoantibodies were detected by immunofluorescence on tissue cultured bovine retinal pericytes. RESULTS: The prevalence of anti-pericyte autoantibodies in Type 2 diabetic patients was 54% and was approximately equal in men and women. The prevalence was approximately 55% with retinopathy at grades from 10 to 53. At grades above 53 the prevalence declined to 23% ( p<0.0001). The highest prevalence by duration of diabetes, 70%, was found at 0 to 5 years and the lowest, 25% at more than 25 years duration ( p<0.0001). CONCLUSION/INTERPRETATION: Anti-pericyte autoantibodies are present at high prevalence in Type 2 diabetes. Their presence during earlier stages of retinopathy could be due to a reaction with antigens expressed by "activated" pericytes. The decline in antibody prevalence in advanced retinopathy could mark pericyte loss and progression to an angiogenic retinal milieu. 相似文献
76.
Outcome and prognostic indicators of diffuse proliferative lupus glomerulonephritis treated with sequential oral cyclophosphamide and azathioprine 总被引:10,自引:0,他引:10
OBJECTIVE: To study the outcome and prognostic indicators of diffuse proliferative glomerulonephritis (DPGN) in patients with systemic lupus erythematosus (SLE) treated with sequential oral cyclophosphamide (CYC) and azathioprine (AZA). METHODS: SLE patients with biopsy-proven DPGN treated with sequential oral CYC and AZA were studied. Those who achieved renal remission at 12 months were identified, and the clinical predictors of complete remission were evaluated by regression analysis. All patients were followed up until a relapse of the nephritis or a doubling of the serum creatinine level occurred. The timing and risk factors for flares and creatinine doubling were evaluated by Kaplan-Meier analysis and with the Cox proportional hazards model. RESULTS: We studied 55 patients (47 women, 8 men; mean +/- SD age at renal biopsy 31.1 +/- 10.4 years); 25 (46%) had a serum creatinine level >106 micromoles/liter, and 29 (53%) had nephrotic syndrome. At 12 months posttreatment, 37 (67%) had complete remission and 12 (22%) had partial remission. The initial serum creatinine level was an independent predictor of complete remission. Excluding the 4 patients who were treatment- resistant or died, 21 patients (41%) had renal flares during a median followup of 4 years. The cumulative risk of renal flare was 6% at 1 year, 21% at 3 years, and 32% at 5 years. The median time to relapse was 43 months. The histologic activity score and the mean daily dose of CYC were multivariate predictors of renal flare, by Cox regression. At the last followup visit, 9 of 54 patients (17%) had a doubling of the creatinine level, 6 of whom (11%) underwent dialysis. The cumulative risk of creatinine doubling was 8.4% at 5 years and 18.2% at 10 years. An increasing chronicity index at the time of initial renal biopsy was an independent predictor of deterioration in renal function. CONCLUSION: Sequential therapy with oral CYC followed by AZA appears to be an effective treatment regimen for DPGN in patients with SLE, with 89% of patients achieving complete or partial remission at 12 months, 62.8% remaining in remission after 5 years, and 81.8% having stable renal function after 10 years. Predictors of treatment resistance and relapse include increasing serum creatinine level, higher histologic activity scores, and a lower dose of CYC. Increasing chronicity indices predict a deterioration of renal function. 相似文献
77.
Ying-Chung Lee Chi-Chang Juan Victor S. Fang Yung-Pei Hsu Shu-Hsia Lin Ching-Fai Kwok Low-Tone Ho 《Metabolism: clinical and experimental》1998,47(12):1468-1471
The specificity of endothelin (ET) receptors involved in the inhibition of insulin-stimulated glucose uptake (ISGU) in rat adipocytes was investigated. Adipocytes were isolated from the epididymal fat pads of Sprague-Dawley rats. To determine receptor subtypes, we used three ET isopeptides, ET-1 and ET-2, both of which are nonselective agonists, and ET-3, a selective agonist for ETc receptors, to displace [125I]ET-1 binding from the fat cells. The efficiency of displacement was ET-1 > ET-2 ? ET-3, indicating that the primary receptors involved belonged to the ETa subtype. At an equal concentration of 1 μmol/L, BQ-610, a selective ETa antagonist, displaced [125I]ET-1 from binding to fat cells, whereas IRL-1038, a selective ETb antagonist, did not. Using [3H]2-deoxy-d-1-glucose ([3H]2-DG) as a tracer in studies of glucose uptake, we found that equimolar BQ-610 completely reversed the inhibitory effect of ET-1 on ISGU, whereas IRL-1038 was ineffective. Northern blot analysis of adipocyte receptors showed abundant mRNA for ETa, but no ETb subtype. These results clearly demonstrate that ETa is the predominant receptor in rat adipocytes. 相似文献
78.
Karen Y. Kwok Timmy L. S. Choi Wai Him Kwok Ming Yip Lau Elvis M. K. Leung Gary N. W. Leung Jenny K. Y. Wong Terence S. M. Wan Farrington F. Adrian Anil Prabhu Emmie N. M. Ho 《Drug testing and analysis》2020,12(9):1274-1286
The use of bioactive peptides as a doping agent in both human and animal sports has become increasingly popular in recent years. As such, methods to control the misuse of bioactive peptides in equine sports have received attention. This paper describes a sensitive accurate mass method for the detection of 40 bioactive peptides and two non‐peptide growth hormone secretagogues (< 2 kDa) at low pg/mL levels in horse urine using ultra‐high performance liquid chromatography‐high resolution mass spectrometry (UHPLC/HRMS). A simple mixed‐mode cation exchange solid‐phase extraction (SPE) cartridge was employed for the extraction of 42 targets and/or their in vitro metabolites from horse urine. The final extract was analyzed using UHPLC/HRMS in positive electrospray ionization (ESI) mode under both full scan and data independent acquisition (DIA, for MS2). The estimated limits of detection (LoD) for most of the targets could reach down to 10 pg/mL in horse urine. This method was validated for qualitative detection purposes. The validation data, including method specificity, method sensitivity, extraction recovery, method precision, and matrix effect were reported. A thorough in vitro study was also performed on four gonadotrophin‐releasing factors (GnRHs), namely leuprorelin, buserelin, goserelin, and nafarelin, using the S9 fraction isolated from horse liver. The identified in vitro metabolites have been incorporated into the method for controlling the misuse of GnRHs. The applicability of this method was demonstrated by the identification of leuprorelin and one of its metabolites, Leu M4, in urine obtained after intramuscular administration of leuprorelin to a thoroughbred gelding (castrated horse). 相似文献
79.
Jenny K.Y. Wong George H.M. Chan Timmy L.S. Choi Karen Y. Kwok Ming Y. Lau Gary N.W. Leung Terence S.M. Wan Emmie N.M. Ho 《Drug testing and analysis》2020,12(7):900-917
A high‐throughput method has been developed for the doping control analysis of 124 drug targets, processing up to 154 horse urine samples in as short as 4.5 h, from the time the samples arrive at the laboratory to the reporting deadline of 30 min before the first race, including sample receipt and registration, preparation and instrument analysis and data vetting time. Sample preparation involves a brief enzyme hydrolysis step (30 min) to detect both free and glucuronide‐conjugated drug targets. This is followed by extraction using solid‐supported liquid extraction (SLE) and analysis using liquid chromatography–high‐resolution mass spectrometry (LC–HRMS). The entire set‐up comprised of four sets of Biotage Extrahera automation systems for conducting SLE and five to six sets of Orbitrap for instrumental screening using LC–HRMS. Suspicious samples flagged were subject to confirmatory analyses using liquid chromatography–triple quadrupole mass spectrometry. The method comprises 124 drug targets from a spectrum of 41 drug classes covering acidic, basic and neutral drugs. More than 85% of the targets had limits of detection at or below 5 ng/mL in horse urine, with the lowest at 0.02 ng/mL. The method was validated for qualitative identification, including specificity, sensitivity, extraction recovery and precision. Method applicability was demonstrated by the successful detection of different drugs, namely (a) butorphanol, (b) dexamethasone, (c) diclofenac, (d) flunixin and (e) phenylbutazone, in post‐race or out‐of‐competition urine samples collected from racehorses. This method was developed for pre‐race urine testing in Hong Kong; however, it is also suitable for testing post‐race or out‐of‐competition urine samples, especially when a quick total analysis time is desired. 相似文献
80.
Yvonne T Tsang Michael T Deavers Charlotte C Sun Suet‐Yan Kwan Eric Kuo Anais Malpica Samuel C Mok David M Gershenson Kwong‐Kwok Wong 《The Journal of pathology》2013,231(4):449-456
BRAF and KRAS mutations in ovarian serous borderline tumours (OSBTs) and ovarian low‐grade serous carcinomas (LGSCs) have been previously described. However, whether those OSBTs would progress to LGSCs or whether those LGSCs were developed from OSBT precursors in previous studies is unknown. Therefore, we assessed KRAS and BRAF mutations in tumour samples from 23 recurrent LGSC patients with a known initial diagnosis of OSBT. Paraffin blocks from both OSBT and LGSC samples were available for five patients, and either OSBTs or LGSCs were available for another 18 patients. Tumour cells from paraffin‐embedded tissues were dissected out for mutation analysis by conventional polymerase chain reaction (PCR) and Sanger sequencing. Tumours that appeared to have wild‐type KRAS by conventional PCR–Sanger sequencing were further analysed by full COLD (co‐amplification at lower denaturation temperature)‐PCR and deep sequencing. Full COLD‐PCR was able to enrich the amplification of mutated alleles. Deep sequencing was performed with the Ion Torrent personal genome machine (PGM). By conventional PCR–Sanger sequencing, BRAF mutation was detected only in one patient and KRAS mutations were detected in ten patients. Full COLD‐PCR deep sequencing detected low‐abundance KRAS mutations in eight additional patients. Three of the five patients with both OSBT and LGSC samples available had the same KRAS mutations detected in both OSBT and LGSC samples. The remaining two patients had only KRAS mutations detected in their LGSC samples. For patients with either OSBT or LGSC samples available, KRAS mutations were detected in seven OSBT samples and six LGSC samples. Surprisingly, patients with the KRAS G12V mutation have shorter survival times. In summary, KRAS mutations are very common in recurrent LGSC, while BRAF mutations are rare. The findings indicate that recurrent LGSC can arise from proliferation of OSBT tumour cells with or without detectable KRAS mutations. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献