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11.
Jay R. Dave Ankush M. Dewle Suhas T. Mhaske Prashant T. Phulpagar Vikas L. Mathe Supriya E. More Ayesha A. Khan Appala Venkata Ramana Murthy Suwarna S. Datar Ajay J. Jog Megha Page Geetanjali B. Tomar 《Nanomedicine : nanotechnology, biology, and medicine》2019,15(1):218-230
Parathyroid hormone (PTH) has been a major contributor to the anabolic therapy for osteoporosis, but its delivery to bone without losing activity and avoiding adverse local effects remain a challenge. Being the natural component of bone, use of hydroxyapatite for this purpose brings a major breakthrough in synergistic anabolism. This study focuses on synthesis, characterization and evaluation of in vitro and in vivo efficacy of PTH (1-34) adsorbed hydroxyapatite nanocarrier for synergistic enhancement in the anabolic activity of PTH for bone regeneration. The negative zeta potential of this nanocarrier facilitated its affinity to the Ca2+ rich bone tissue and solubilization at low pH enhanced specific delivery of PTH to the resorption pits in osteoporotic bone. In this process, PTH retained its anabolic effect and at the same time an increase in bone mineral content indicated enhancement of the net formative effect of the PTH anabolic therapy. 相似文献
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Steven M. Kawut Hooman D. Poor Megha A. Parikh Katja Hueper Benjamin M. Smith David A. Bluemke João A.C. Lima Martin R. Prince Eric A. Hoffman John H.M. Austin Jens Vogel-Claussen R. Graham Barr 《Journal of the American College of Cardiology》2014
Background
The classic cardiovascular complication of chronic obstructive pulmonary disease (COPD) is cor pulmonale or right ventricular (RV) enlargement. Most studies of cor pulmonale were conducted decades ago.Objectives
This study sought to examine RV changes in contemporary COPD and emphysema using cardiac magnetic resonance (CMR) imaging.Methods
We performed a case-control study nested predominantly in 2 general population studies of 310 participants with COPD and control subjects 50 to 79 years of age with ≥10 pack-years of smoking who were free of clinical cardiovascular disease. RV volumes and mass were assessed using magnetic resonance imaging. COPD and COPD severity were defined according to standard spirometric criteria. The percentage of emphysema was defined as the percentage of lung regions <−950 Hounsfield units on full-lung computed tomography; emphysema subtypes were scored by radiologists. Results were adjusted for age, race/ethnicity, sex, height, weight, smoking status, pack-years, systemic hypertension, and sleep apnea.Results
Right ventricular end-diastolic volume (RVEDV) was reduced in COPD compared with control subjects (−7.8 ml; 95% confidence interval: −15.0 to −0.5 ml; p = 0.04). Increasing severity of COPD was associated with lower RVEDV (p = 0.004) and lower RV stroke volume (p < 0.001). RV mass and ejection fraction were similar between the groups. A greater percentage of emphysema also was associated with lower RVEDV (p = 0.005) and stroke volume (p < 0.001), as was the presence of centrilobular and paraseptal emphysema.Conclusions
RV volumes are lower without significant alterations in RV mass and ejection fraction in contemporary COPD, and this reduction is related to the greater percentage of emphysema on computed tomography. 相似文献13.
Donatella Spina Lorenzo Leoncini Tiziana Megha Maria T. Del Vecchio Chiara Minacci Simonetta Poggi Stefano Pileri Piero Tosi Rainer Kraft Jean A. Laissue Hans Cottier 《International journal of cancer. Journal international du cancer》1996,68(4):436-440
The present study examined whether growth characteristics of diffusely growing non-Hodgkin's lymphomas (NHL) may differ as a function of stage. Among 105 NHL of various types and sub-types (REAL [Revised European-American Lymphoma] classification), localized (Ann Arbor pathologic stages I + II) lymphomas exhibited clearly higher indices for mitotic activity, apoptosis and cell turnover, as well as a significantly lower percentage of cells containing immunohistochemically detectable bcl-2 protein, than disseminated (stages III + IV) NHL. A similar pattern emerged when high-grade (Kiel classification) lymphomas only were evaluated. Low-grade NHL showed analogous, but less marked, stage-dependent characteristics, with the exception of median percentages of bcl-2+ cells, which remained comparable in all stages. Our findings are consistent with the notion that dissemination of diffusely growing NHL is usually associated with reduced cell turnover and, in high-grade lymphomas, with the generation of longer-lived cells. © 1996 Wiley-Liss, Inc. 相似文献
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Brahme Radhika Mamulwar Megha Rahane Girish Jadhav Sachin Panchal Narayan Yadav Rajesh Gangakhedkar Raman 《Indian journal of pediatrics》2020,87(4):275-280
Indian Journal of Pediatrics - Youth and adolescents are the priority population to target the interventions as risky behaviors persist and they contribute to almost half of the new Human... 相似文献
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Lorenzo Leoncini Donatella Spina Pauline Close Tiziana Megha Lorenzo Pacenti Piero Tosi Stefano Pileri Antonio De Vivo Rainer Kraft Jean A. Laissue Hans Cottier 《Leukemia & lymphoma》1996,22(1):119-124
This study was undertaken to better comprehend the reasons for the scarcity of Hodgkin and Reed-Sternberg (H-RS) cells in Hodgkin's disease (HD) despite their expression of “proliferation-associated antigens”. To this end, we assessed the relative frequency of mitotic phases and nuclear damage (detected by in situ end-labeling of DNA strand breaks) in CD30+ large cells of nodular sclerosis and mixed cellularity HD. Our results show that a) most CD30+ cells in HD exhibit abortive mitoses, with a highly significant arrest at the metaphase-ana/telophase transition, and b) many of these elements, i.e. mainly H-RS cells, show fragmentation of nuclear DNA, suggesting imminent or actual death. Percentages of CD30+ cells that entered mitosis and those with DNA strand breaks were of a similar order of magnitude and correlated significantly in a linear fashion. These findings are consistent with the concept that cell deletion is the major cause of the paucity of H-RS cells in HD. 相似文献
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Incidence of basal cell and squamous cell carcinomas in a population younger than 40 years 总被引:4,自引:0,他引:4
Christenson LJ Borrowman TA Vachon CM Tollefson MM Otley CC Weaver AL Roenigk RK 《JAMA》2005,294(6):681-690
Context The incidence of nonmelanoma skin cancer is increasing rapidly among elderly persons, but little is known about its incidence in the population younger than 40 years. Objectives To estimate the sex- and age-specific incidences of basal cell carcinoma and squamous cell carcinoma in persons younger than 40 years in Olmsted County, Minnesota, and to evaluate change in incidence over time; to describe the clinical presentation, rate of recurrence and metastasis, and histologic characteristics of these tumors in this population-based sample. Design Population-based retrospective incidence case review. Setting Residents of Olmsted County, Minnesota, a population with comprehensive medical records captured through the Rochester Epidemiology Project. Participants Patients younger than 40 years with basal cell carcinoma or squamous cell carcinoma diagnosed between 1976 and 2003. Main Outcome Measures Incident basal cell carcinomas and squamous cell carcinomas and change in incidence of these tumors over time. Results During the study period, 451 incident basal cell carcinomas were diagnosed in 417 patients and 70 incident squamous cell carcinomas were diagnosed in 68 patients. Of these tumors, 328 were histologically confirmed basal cell carcinomas and 51 were histologically confirmed squamous cell carcinomas. Overall, the age-adjusted incidence of basal cell carcinoma per 100 000 persons was 25.9 (95% confidence interval [CI], 22.6-29.2) for women and 20.9 (95% CI, 17.8-23.9) for men. The incidence of basal cell carcinoma increased significantly during the study period among women (P<.001) but not men (P = .19). Nodular basal cell carcinoma was the most common histologic subtype; 43.0% of tumors were solely nodular basal cell carcinoma and 11.0% had a mixed composition, including the nodular subtype. The incidence of squamous cell carcinoma was similar in men and women, with an average age- and sex-adjusted incidence per 100 000 persons of 3.9 (95% CI, 3.0-4.8); the incidence of squamous cell carcinoma increased significantly over the study period among both women (P = .01) and men (P = .04). Conclusions This population-based study demonstrated an increase in the incidence of nonmelanoma skin cancer among young women and men residing in Olmsted County, Minnesota. There was a disproportionate increase in basal cell carcinoma in young women. This increase may lead to an exponential increase in the overall occurrence of nonmelanoma skin cancers over time as this population ages, which emphasizes the need to focus on skin cancer prevention in young adults. 相似文献
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