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91.
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Background
Minimization as an adaptive allocation technique has been recommended in the literature for use in randomized clinical trials. However, it remains uncommonly used due in part to a lack of easily accessible implementation tools.Objective
To provide clinical trialists with a robust, flexible, and readily accessible tool for implementing covariate-adaptive biased-coin randomization.Methods
We developed a Web-based random allocation system, MinimRan, that applies Pocock–Simon (for trials with 2 or more arms) and 2-way (currently limited to 2-arm trials) minimization methods for trials using only categorical prognostic factors or the symmetric Kullback–Leibler divergence minimization method for trials (currently limited to 2-arm trials) using continuous prognostic factors with or without categorical factors, in covariate-adaptive biased-coin randomization.Results
In this paper, we describe the system’s essential statistical and computer programming features and provide as an example the randomization results generated by it in a recently completed trial. The system can be used in single- and double-blind trials as well as single-center and multicenter trials.Conclusions
We expect the system to facilitate the translation of the 3 validated random allocation methods into broad, efficient clinical research practice. 相似文献93.
Rosenblatt HM Stanley KE Song LY Johnson GM Wiznia AA Nachman SA Krogstad PA;Pediatric AIDS Clinical Trials Group Study Team 《The Journal of infectious diseases》2005,192(3):445-455
We studied changes in 60 immunological parameters after the administration of highly active antiretroviral therapy (HAART) in 192 clinically stable antiretroviral drug-experienced HIV-1-infected children 4 months-17 years old. The studied immunological parameters included standard lymphocyte subsets and lymphocyte surface markers of maturation and activation. The most significant changes during the 48-week study period were seen for CD8(+), CD8(+)CD62L(+)CD45RA(+), CD8(+)CD38(+)HLA-DR(+), and CD4(+) T cell percentages (P < .0001 for all parameters). These changes suggest that significant decreases in the expression of activation markers and increases in the expression of naive markers in the CD8(+) T cell population may be related to better virologic control in these HIV-1-infected children, who had relatively stable immune function at the initiation of HAART. At week 44 of HAART, the major immunological parameters in these HIV-1-infected children moved from baseline values to about halfway to two-thirds of the way toward the values in healthy, uninfected children. 相似文献
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Luca Masotti Grazia Panigada Giancarlo Landini Filippo Pieralli Francesco Corradi Salvatore Lenti Rino Migliacci Stefano Arrigucci Anna Frullini Maria Chiara Bertieri Stefano Tatini Alberto Fortini Irene Cascinelli Nicola Mumoli Stefano Giuntoli Alessandro De Palma Veronica De Crescenzo Michele Piacentini Giancarlo Tintori Alba Dainelli Giuseppa Levantino Plinio Fabiani Filippo Risaliti Roberta Mastriforti Michele Voglino Valentina Carli Simone Meini 《Journal of thrombosis and thrombolysis》2016,41(4):606-612
Prognostic stratification of acute pulmonary embolism (PE) remains a challenge in clinical practice. Simplified PESI (sPESI) score is a practical validated score aimed to stratify 30-day mortality risk in acute PE. Whether prognostic value of sPESI score differs according to sex has not been previously investigated. Therefore the aim of our study was to provide information about it. Data records of 452 patients, 180 males (39.8 %) and 272 females (60.2 %) discharged for acute PE from Internal Medicine wards of Tuscany (Italy) were analysed. sPESI was retrospectively calculated. Variables enclosed in sPESI score, all cause in-hospital mortality and overall bleedings were compared between sexes. Moreover, predictive ability of sPESI score as prognosticator of all cause in-hospital mortality was tested and compared between sexes. sPESI score 0 (low risk) was found in 17.7 % of males and 13.6 % of females (p = 0.2323). We didn’t find significant difference in sPESI scoring distribution. Age ≥80 years (51.4 vs. 33.8 %, p = 0.0003) and heart rate ≥110 bpm (23.5 vs. 14.4 %, p = 0.0219) were found significantly more prevalent in females, whereas active cancer (23.8 vs. 39.4 %, p = 0.0004) and cardio-respiratory diseases (19.8 vs. 27.7 %, p = 0.0416) were in males. All cause in-hospital mortality was 0 % in both genders for sPESI score 0, whereas it was 5.4 % in females and 13.6 % in males with sPESI score 1–2 (p = 0.0208) and 22 % in females and 19.3 % in males with sPESI score ≥3 (p = 0.7776). Overall bleedings were significantly more frequent in females compared with males (4.77 vs. 0.55 %, p = 0.0189). In females overall bleedings ranged from 2.7 % in sPESI score 0 to 6 % in sPESI score ≥3. Predictive ability of sPESI score as prognosticator of all cause in-hospital mortality was higher in females compared to males (AUC 0.72 vs. 0.67, respectively). In real life different co-morbidity burdens in females compared to males. Females seems to be at lower risk of all cause in-hospital mortality for sPESI score ≤2 but at higher risk of bleeding, irrespective from sPESI scoring. Predictive ability of sPESI score seems better in females. 相似文献
97.
Gisela G. Slaats Joshua C. Saldivar Julien Bacal Michelle K. Zeman Andrew C. Kile Ann Marie Hynes Shalabh Srivastava Jekaterina Nazmutdinova Krista den Ouden Miriam S. Zagers Veronica Foletto Marianne C. Verhaar Colin Miles John A. Sayer Karlene A. Cimprich Rachel H. Giles 《The Journal of clinical investigation》2015,125(9):3657-3666
Juvenile ciliopathy syndromes that are associated with renal cysts and premature renal failure are commonly the result of mutations in the gene encoding centrosomal protein CEP290. In addition to centrosomes and the transition zone at the base of the primary cilium, CEP290 also localizes to the nucleus; however, the nuclear function of CEP290 is unknown. Here, we demonstrate that reduction of cellular CEP290 in primary human and mouse kidney cells as well as in zebrafish embryos leads to enhanced DNA damage signaling and accumulation of DNA breaks ex vivo and in vivo. Compared with those from WT mice, primary kidney cells from Cep290-deficient mice exhibited supernumerary centrioles, decreased replication fork velocity, fork asymmetry, and increased levels of cyclin-dependent kinases (CDKs). Treatment of Cep290-deficient cells with CDK inhibitors rescued DNA damage and centriole number. Moreover, the loss of primary cilia that results from CEP290 dysfunction was rescued in 3D cell culture spheroids of primary murine kidney cells after exposure to CDK inhibitors. Together, our results provide a link between CEP290 and DNA replication stress and suggest CDK inhibition as a potential treatment strategy for a wide range of ciliopathy syndromes. 相似文献
98.
Francesca Prignano Veronica Rogai Elisabetta Cavallucci Alessandro Bitossi Volker Hammen Fabrizio Cantini 《Current rheumatology reports》2018,20(7):43
Purpose of Review
Understanding prevalence of diseases within specific regions of a country is important for optimal allocation of healthcare resources/funds. We performed a systematic review to obtain a clearer picture of the epidemiology of psoriasis and psoriatic arthritis across and within specific regions of Italy.Recent Findings
Prevalence of psoriasis in specific regions showed more variability (0.8–4.5%) than that in the total population (1.8–3.1%). Prevalence of psoriatic arthritis in the general population was reported for only two regions, Chiavari (0.09%) and Marche (0.42%). All other studies reported prevalence of psoriatic arthritis in patients with psoriasis in single centres and Italy-wide (4.7–47.1%). Prevalence of psoriatic arthritis was highest in patients with nail and/or scalp psoriasis and/or intergluteal/perianal region involvement.Summary
Based on current available data, these conditions appear to affect a substantial number of people and will likely have an important impact on the Italian healthcare system.99.
The role of the resting zone in growth plate chondrogenesis 总被引:8,自引:0,他引:8
Abad V Meyers JL Weise M Gafni RI Barnes KM Nilsson O Bacher JD Baron J 《Endocrinology》2002,143(5):1851-1857
In mammals, growth of long bones occurs at the growth plate, a cartilage structure that contains three principal layers: the resting, proliferative, and hypertrophic zones. The function of the resting zone is not well understood. We removed the proliferative and hypertrophic zones from the rabbit distal ulnar growth plate in vivo, leaving only the resting zone. Within 1 wk, a complete proliferative and hypertrophic zone often regenerated. Next, we manipulated growth plates in vivo to place resting zone cartilage ectopically alongside the proliferative columns. Ectopic resting zone cartilage induced a 90-degree shift in the orientation of nearby proliferative zone chondrocytes and seemed to inhibit their hypertrophic differentiation. Our findings suggest that resting zone cartilage makes important contributions to endochondral bone formation at the growth plate: 1) it contains stem-like cells that give rise to clones of proliferative chondrocytes; 2) it produces a growth plate-orienting factor, a morphogen, that directs the alignment of the proliferative clones into columns parallel to the long axis of the bone; and 3) it may also produce a morphogen that inhibits terminal differentiation of nearby proliferative zone chondrocytes and thus may be partially responsible for the organization of the growth plate into distinct zones of proliferation and hypertrophy. 相似文献
100.