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We read with interest the commentary by Skeldon and Dijk about our article “Weekly, seasonal and chronotype-dependent variation of dim light melatonin onset.” The discussion points raised by Skeldon and Dijk are currently among the most hotly debated in human circadian science. What external factors determine human phase of entrainment? How great is the contribution of natural versus artificial light and sun time versus social time? Our intra-individual data add to the still limited evidence from field studies in this matter. In their commentary, Skeldon and Dijk formulate two either-or hypotheses, postulating that humans entrain either solely to the natural light-dark cycle (sun time referenced by midday) (H1) or solely to the light selected by local clock time and social constraints (H2). Neither hypothesis accounts for the effect of season on human light exposure. We interpreted our findings along more complex lines, speculating that the 1-h earlier melatonin rise in summer found in our sample is likely the combined result of daylight saving time (DST)-induced behavioral advances and a stronger natural zeitgeber in summer (light exposure determined by social and seasonal factors, Horiginal). Here, we show how the criticism by Skeldon and Dijk is based on two sentences quoted out of context (misrepresenting our hypothesis as H1) and that their hypothesis H2 leaves out important seasonal components in light exposure.  相似文献   
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IntroductionSeptic arthritis is a serious orthopaedic emergency that must be diagnosed and managed early to prevent devastating complications. The current gold standard for diagnosing septic arthritis is synovial fluid culture, but results are delayed by 48–72 h, and the sensitivity of the test is very low. Differentiating Septic from non-septic arthritis is vital to prevent unnecessary use of antibiotics and prevent complications. Serum Procalcitonin (PCT) is a useful marker in differentiating septic from non-septic arthritis but there are very few studies that have studied the role of synovial PCT for the same.AimTo determine the role of serum and synovial PCT in differentiating acute Septic from non-septic arthritis.Materials and methodsProspective clinical study in which 60 patients presenting with acute inflammatory arthritis (<2 weeks duration) were enrolled from May 2018 to May 2020. Serum and synovial fluid samples were drawn at presentation and routine blood investigations, synovial fluid culture sensitivity, and Procalcitonin levels were measured. Patients were divided into 3 groups, with group-1 having confirmed pyogenic, group-2 having presumed pyogenic, and group-3 having non –pyogenic patients, respectively. All data was tabulated and statistically analysed using appropriate tests.ResultsMean serum PCT values in groups 1, 2 and 3 were 1.06 ± 1.11, 0.85 ± 0.74, and 0.11 ± 0.24, respectively. Patients in the Pyogenic group (group1 and group 2) had significantly higher mean serum PCT as compared to group3 (p < 0.0001). Group 1 had higher serum PCT as compared to group 2, but the difference was not significant (p = 0.58). Mean synovial PCT in group 1, 2 and 3 were 2.42 ± 1.98, 1.89 ± 1.18, and 0.22 ± 0.40, respectively. Patients in the Pyogenic group (Group1 and Group2) had significantly higher mean synovial PCT as compared to Group 3 (p < 0.0001). Group 1 had higher mean synovial PCT as compared to group 2, but the difference was not significant (p = 0.54). The area under the ROC curve of the serum levels of PCT was 0.0.895, and the area under the ROC curve of the synovial fluid levels of PCT was 0.914, which was higher than the serum PCT level.ConclusionSerum and synovial Procalcitonin may be used as a diagnostic marker in differentiating septic from inflammatory arthritis and can help in reducing unnecessary use of antibiotics and early diagnosis and management of septic arthritis, thereby preventing complications.  相似文献   
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Quantitative susceptibility mapping (QSM) has the potential for being a biomarker for various diseases because of its ability to measure tissue susceptibility related to iron deposition, myelin, and hemorrhage from the phase signal of a T2*-weighted MRI. Despite its promise as a quantitative marker, QSM is faced with many challenges, including its dependence on preprocessing of the raw phase data, the relatively weak tissue signal, and the inherently ill posed relationship between the magnetic dipole and measured phase. The goal of this study was to evaluate the effects of background field removal and dipole inversion algorithms on noise characteristics, image uniformity, and structural contrast for cerebral microbleed (CMB) quantification at both 3T and 7T. We selected four widely used background phase removal and five dipole field inversion algorithms for QSM and applied them to volunteers and patients with CMBs, who were scanned at two different field strengths, with ground truth QSM reference calculated using multiple orientation scans. 7T MRI provided QSM images with lower noise than did 3T MRI. QSIP and VSHARP + iLSQR achieved the highest white matter homogeneity and vein contrast, with QSIP also providing the highest CMB contrast. Compared with ground truth COSMOS QSM images, overall good correlations between susceptibility values of dipole inversion algorithms and the COSMOS reference were observed in basal ganglia regions, with VSHARP + iLSQR achieving the susceptibility values most similar to COSMOS across all regions. This study can provide guidance for selecting the most appropriate QSM processing pipeline based on the application of interest and scanner field strength.  相似文献   
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Fibroblast growth factor receptors (FGFR) are a family of transmembrane receptor tyrosine kinases involved in regulating cellular processes. FGFR mutations are implicated in oncogenesis, representing therapeutic potential in the form of FGFR inhibitors. This phase I, first‐in‐human study in Japan evaluated safety and tolerability of E7090, a potent selective FGFR1‐3 inhibitor, in patients with advanced solid tumors. Dose escalation (daily oral dose of 1‐180 mg) was carried out to assess dose‐limiting toxicity (DLT), maximum tolerated dose, and pharmacokinetics. Pharmacodynamic markers (serum phosphate, fibroblast growth factor 23, and 1,25‐(OH)2‐vitamin D) were also evaluated. A total of 24 patients refractory to standard therapy or for whom no appropriate treatment was available were enrolled. No DLT were observed up to the 140‐mg dose; one patient in the 180‐mg cohort experienced a DLT (increased aspartate aminotransferase/alanine aminotransferase, grade 3). The maximum tolerated dose was not reached. Dose‐dependent increases in the maximum concentration and area under the curve from time 0 to the last measurable concentration were observed up to 180 mg. Dose‐dependent increases were observed in all pharmacodynamic markers and plateaued at 100‐140 mg, indicating sufficient FGFR pathway inhibition at doses ≥100 mg. In conclusion, E7090 showed a manageable safety profile with no DLT at doses ≤140 mg. Maximum tolerated dose was not determined. The recommended dose for the follow‐up expansion part, restricted to patients with tumors harboring FGFR alterations, was determined as 140 mg, once daily.  相似文献   
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目的优化1,8-桉叶油素(1,8-cineole,1,8-Cin)自微乳给药系统(1,8-cineole self-microemulsion drug delivery system,1,8-Cin-SMEDDS)处方,对其进行表征并进行细胞摄取考察。方法通过绘制伪三元相图,确定1,8-Cin-SMEDDS有效自乳化区域,进行初步处方筛选。以粒径和载药量为指标,采用星点设计-效应面法对1,8-Cin-SMEDDS处方进行优化并验证。荧光显微镜观察高糖损伤的人脐静脉内皮细胞(HUVEC)对1,8-Cin-SMEDDS的摄取情况。结果 1,8-Cin-SMEDDS的最佳处方是大豆油(7.5%)与1,8-Cin(22.5%)为混合油相,HS15(56%)为乳化剂,乙醇(14%)为助乳化剂,滴加纯水至8m L得半透明略带蓝色乳光液体。透射电镜观察其外观呈球形液滴,激光粒度Zeta电位测定仪测得平均粒径为(131.68±1.44)nm,Zeta电位为(-10.03±1.63)m V;HPLC法测得包封率为(99.890±0.012)%,载药量为(224.750±0.028)mg/g。HUVEC细胞摄取实验结果表明,细胞对1,8-Cin-SMEDDS的摄取高于游离1,8-Cin。结论 1,8-Cin-SMEDDS制备方法简便,重复性好,所得1,8-Cin-SMEDDS外观良好,包封率高,理化性质稳定,且能促进细胞摄取。  相似文献   
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ObjectiveThe Biological Rhythms Interview of Assessment in Neuropsychiatry (BRIAN) might be applicable for assessing delayed sleep-wake phase disorder (DSWPD). We aimed to investigate the reliability and validity of the Japanese version of the BRIAN self-report (J-BRIAN-SR) in DSWPD patients and determine a cutoff score to identify the presence of the disorder.MethodsWe enrolled 60 newly diagnosed DSWPD outpatients and 64 age-matched healthy controls. We used Cronbach's alpha for internal reliability to evaluate J-BRIAN-SR. We confirmed the reliability of the A test and re-test using Pearson's correlation coefficient in the controls. We used confirmatory factor analysis to evaluate the factor structure of J-BRIAN-SR and referenced the Morningness-Eveningness Questionnaire (MEQ) to check concurrent validity. We analyzed the receiver operating characteristic curve (ROC) to determine the J-BRIAN-SR cutoff point for the presence of DSWPD.ResultsThe 18-component scores of the J-BRIAN-SR had an overall reliability coefficient (Cronbach's alpha) of 0.82. We confirmed a high test-retest reliability using an intraclass correlation coefficient (r = 0.84). The correlation between J-BRIAN-SR and MEQ was 0.38 (p = 0.003). The J-BRIAN-SR that we extracted by exploratory factor analysis consisted of three factors. A score of 40 points provided a sensitivity of 80.0% and a specificity of 75.6% for the positivity of DSWPD.ConclusionsThe results of the present study revealed that J-BRIAN-SR is a valid and reliable instrument for screening and evaluating the severity of DSWPD. Our findings will be useful to physicians and patients in Japan and those in clinical settings.  相似文献   
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We aim to assess the safety and efficacy of proxalutamide, a novel androgen receptor antagonist, for men with metastatic castration-resistant prostate cancer (mCRPC) in a multicenter, randomized, open-label, phase 2 trial. In our study, the enrolled mCRPC patients were randomized to 100, 200 and 300 mg dose groups at 1:1:1. The primary efficacy endpoint was prostate-specific antigen (PSA) response rate. The secondary endpoints included objective response rate (ORR), disease control rate (DCR) and time to PSA and radiographic progression. Safety and pharmacokinetics were also assessed. Finally, there were 108 patients from 17 centers being enrolled. By week 16, there were 13 (35.1%), 12 (36.4%) and 15 (42.9%) patients with confirmed 50% or greater PSA decline in 100 mg (n = 37), 200 mg (n = 33) and 300 mg (n = 35) groups, respectively. Among the 19 patients with target lesions at study entry, three (15.8%) had a partial response and 12 (63.2%) had stable disease. The ORRs of 20.0%, 22.2%, 0% and DCRs of 80.0%, 88.9%, 60.0% were, respectively, achieved in 100, 200 and 300 mg groups. By the maximum follow-up time of 24 weeks, there were 42.6% and 10.2% of cases experiencing PSA progression and radiographic progression, respectively. Overall, adverse events (AEs) were experienced by 94.4% of patients, most of which were mild or moderate. There were 28 patients experiencing ≥grade 3 AEs. The most common AEs were fatigue (17.6%), anemia (14.8%), elevated AST (14.8%) and ALT (13.0%), decreased appetite (13.0%). These findings preliminarily showed the promising antitumor activity of proxalutamide in patients with mCRPC with a manageable safety profile. The proxalutamide dose of 200 mg daily is recommended for future phase 3 trial (Clinical trial registration no. CTR20170177).  相似文献   
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