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31.
Jonathan Kentley Rina Allawh Swati Rao Alden Doyle Amar Ahmad Kumar Nadhan Charlotte Proby Catherine A. Harwood Christina L. Chung 《American journal of transplantation》2021,21(3):1215-1226
Organ transplant recipients (OTRs) are at increased risk of cutaneous malignancy. Skin disorders in OTRs of color (OTRoC) have rarely been systematically assessed. We aimed to ascertain the burden of skin disease encountered in OTRoC by prospectively collecting data from OTRs attending 2 posttransplant skin surveillance clinics: 1 in London, UK and 1 in Philadelphia, USA. Retrospective review of all dermatological diagnoses was performed. Data from 1766 OTRs were analyzed: 1024 (58%) white, 376 (21%) black, 261 (15%) Asian, 57 (3%) Middle Eastern/Mediterranean (ME/M), and 48 (2.7%) Hispanic; and 1128 (64%) male. Viral infections affected 45.1% of OTRs, and were more common in white and ME/M patients (P < .001). Fungal infections affected 28.1% and were more common in ME/M patients (P < .001). Inflammatory skin disease affected 24.5%, and was most common in black patients (P < .001). In addition, 26.4% of patients developed skin cancer. There was an increased risk of skin cancer in white vs nonwhite OTRs (HR 4.4, 95% CI 3.5-5.7, P < .001): keratinocyte cancers were more common in white OTRs (P < .001) and Kaposi sarcoma was more common in black OTRs (P < .001). These data support the need for programs that promote targeted dermatology surveillance for all OTRs, regardless of race/ethnicity or country of origin. 相似文献
32.
Carleigh B. Krubiner Ruth R. Faden Ruth A. Karron Margaret O. Little Anne D. Lyerly Jon S. Abramson Richard H. Beigi Alejandro R. Cravioto Anna P. Durbin Bruce G. Gellin Swati B. Gupta David C. Kaslow Sonali Kochhar Florencia Luna Carla Saenz Jeanne S. Sheffield Paulina O. Tindana 《Vaccine》2021,39(1):85-120
Zika virus, influenza, and Ebola have called attention to the ways in which infectious disease outbreaks can severely – and at times uniquely – affect the health interests of pregnant women and their offspring. These examples also highlight the critical need to proactively consider pregnant women and their offspring in vaccine research and response efforts to combat emerging and re-emerging infectious diseases. Historically, pregnant women and their offspring have been largely excluded from research agendas and investment strategies for vaccines against epidemic threats, which in turn can lead to exclusion from future vaccine campaigns amidst outbreaks. This state of affairs is profoundly unjust to pregnant women and their offspring, and deeply problematic from the standpoint of public health. To ensure that the needs of pregnant women and their offspring are fairly addressed, new approaches to public health preparedness, vaccine research and development, and vaccine delivery are required. This Guidance offers 22 concrete recommendations that provide a roadmap for the ethically responsible, socially just, and respectful inclusion of the interests of pregnant women in the development and deployment of vaccines against emerging pathogens. The Guidance was developed by the Pregnancy Research Ethics for Vaccines, Epidemics, and New Technologies (PREVENT) Working Group – a multidisciplinary, international team of 17 experts specializing in bioethics, maternal immunization, maternal-fetal medicine, obstetrics, pediatrics, philosophy, public health, and vaccine research and policy – in consultation with a variety of external experts and stakeholders. 相似文献
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Effects of diabetes mellitus on the biomechanical properties of human ankle cartilage 总被引:3,自引:0,他引:3
Athanasiou KA Fleischli JG Bosma J Laughlin TJ Zhu CF Agrawal CM Lavery LA 《Clinical orthopaedics and related research》1999,(368):182-189
Metabolic changes attributable to diabetes mellitus affect numerous organ systems in the body. For example, patients with diabetes have an increased number of musculoskeletal injuries and afflictions compared with patients without diabetes and experience more morbidity associated with injury and treatment. Although diabetes also may afflict articular cartilage, no studies have shown a conclusive link between diabetes and cartilage structural integrity. The objective of this study was to obtain and compare the intrinsic material properties of human ankle articular cartilage from patients with diabetes and those without diabetes. These biomechanical properties (aggregate modulus, Poisson's ratio, shear modulus, and permeability) were found to differ significantly between specimens from patients with diabetes and patients without diabetes. Specifically, cartilage from patients with diabetes was significantly softer and more permeable than cartilage from control subjects. For example, in the central portion of the talus, cartilage from patients with diabetes had a 38% smaller aggregate modulus, 37% smaller shear modulus, and 111% larger permeability than did tissue from patients without diabetes. These results provide evidence that joint pathologic processes in patients with diabetes may be associated with compromised structural integrity of articular cartilage. 相似文献
35.
The effect of ultra-high molecular weight polyethylene wear debris on MG63 osteosarcoma cells in vitro 总被引:7,自引:0,他引:7
Dean DD Schwartz Z Liu Y Blanchard CR Agrawal CM Mabrey JD Sylvia VL Lohmann CH Boyan BD 《The Journal of bone and joint surgery. American volume》1999,81(4):452-461
BACKGROUND: Focal osteolysis due to ultra-high molecular weight polyethylene wear debris involves effects on both bone resorption and bone formation. METHODS: The response of MG63 osteoblast-like osteosarcoma cells to ultra-high molecular weight polyethylene wear debris isolated by enzymatic digestion of granulomatous tissue obtained from the sites of failed total hip arthroplasties was examined. Scanning electron microscopy, particle-size analysis, and Fourier transform infrared spectroscopy were used to characterize the number, morphology, size distribution, and chemical composition of the particles. Cell response was assessed by adding particles at varying dilutions to confluent cultures and measuring changes in cell proliferation (number of cells and [3H]-thymidine incorporation), osteoblast function (alkaline-phosphatase-specific activity and osteocalcin production), matrix production (collagen production and proteoglycan sulfation), and local cytokine production (prostaglandin-E2 production). RESULTS: The mean size of the particles was 0.60 micrometer, and 95 percent of the particles had a size of less than 1.5 micrometers. The number of particles per gram of tissue ranged from 1.39 to 3.38x10(9). Three of the four batches of particles were endotoxin-free. Exposure of the cells to particles of wear debris significantly increased the number of cells (p<0.05) and the [3H]-thymidine incorporation (p<0.05) in a dose-dependent manner. In contrast, the addition of particles decreased alkaline-phosphatase-specific activity and osteocalcin production. Collagen production and proteoglycan sulfation were also decreased, while prostaglandin-E2 synthesis was increased by the addition of particles. CONCLUSIONS: Ultra-high molecular weight polyethylene particles isolated from human tissue stimulated osteoblast proliferation and prostaglandin-E2 production and inhibited cell differentiation and matrix production. These results indicate that particles of wear debris inhibit cell functions associated with bone formation and that osteoblasts may produce factors in response to wear debris that influence neighboring cells, such as osteoclasts and macrophages. CLINICAL RELEVANCE: Particles of wear debris, especially ultra-high molecular weight polyethylene, have been implicated in the loosening of implants and the development of osteolysis. The present study shows that particles of ultra-high molecular weight polyethylene isolated from human tissue inhibit osteoblast functions associated with bone formation. In addition, particles of wear debris induced osteoblasts to secrete factors capable of influencing neighboring cells, such as osteoclasts and macrophages. These results suggest that osteoblasts may play a role in the cascade of events leading to granuloma formation, osteolysis, and failure of orthopaedic implants. 相似文献
36.
Agrawal CS Sehgal R Singh RK Gupta AK 《Indian journal of physiology and pharmacology》1999,43(4):501-504
A prospective, randomised and double blind study was undertaken to compare the prophylactic efficacy of ciprofloxacin and cefuroxime in 155 patients undergoing elective cholecystectomy. Patients with past history of jaundice or presence of jaundice, diabetes mellitus, common bile duct stones and previous biliary tract surgery were excluded. Patients were allocated to the following groups: group A-no antibiotic (n = 30); group B-ciprofloxacin (200 mg i/v before surgical incision and a second dose after 12 hrs) (n + 45); group C-ciprofloxacin given only post operatively (200 mg i/v, 12 hourly X 2 days followed by oral 500 mg twice daily X 3 days) (n = 35); group D-cefuroxime (750 mg i/v before surgical incision and a second dose after 12 hrs) (n = 45). Efficacy of the antibiotic was defined as a patient being free of post operative wound infection. Maximum numbers of infection occurred in group A (26.67%) and group C (25.71%). The incidence of wound infection was significantly lower when ciprofloxacin was used as prophylaxis (group B) than when used post operatively (group C) only (P < 0.05). Patients who received ciprofloxacin (group B) and cefuroxime (group D) as prophylaxis had significantly reduced incidence of infection (4.44% and 6/67% respectively); no statistically significant difference was found between these groups. Ciprofloxacin could be used as prophylactic antimicrobial in elective cholecystectomy in developing countries because of its effectiveness, economy and ready availability. 相似文献
37.
Developing new products is a complex and risky business, particularly in the pharmaceutical industry. In recent years, several pretest and test market models have been proposed to evaluate the performance of a new product. Although these models have been tested and validated with a wide variety of frequently purchased products, certain unique characteristics of the market for pharmaceutical products render the models subject to modification. This study examines and evaluates the applicability of three types of market forecasting models (Awareness forecasting models, Pre-test market models, and Test market models) in predicting the market potential of new pharmaceutical products. 相似文献
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In the present study, the applicability of fine particle ethylcellulose (FPEC) to produce matrix tablets by a wet granulation technique was evaluated. The effect of various formulation and process variables, such as FPEC content, hardness of the tablet, and solubility of the drug, on the release of drug from these tablets was examined. Tablets were prepared by wet granulation of drug and FPEC in an appropriate mass ratio. Theophylline, caffeine, and dyphylline were selected as nonionizable model drugs with solubilities from 8.3 to 330 mg/mL at 25°C. Ibuprofen, phenylpropanolamine hydrochloride, and pseudoephedrine hydrochloride were selected as ionizable drugs with solubilities from 0.1 to 2000 mg/mL at 25°C. Drug release studies were conducted in 37°C water with UV detection. As the FPEC content and the hardness of the tablets increased, the release rate of the drug decreased. The drug release rate increased with an increase in the solubility of the drug. Model equations, intended to elucidate the drug release mechanism, were fitted to the release data. Parameters were generated and data presented by SAS software. The Akaike Information Criterion was also considered to ascertain the best-fit equation. Fickian diffusion and polymer relaxation were the release mechanisms for nonionizable and ionizable drugs. 相似文献