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101.
OBJECTIVE: Both falls and low bone density are important in the pathogenesis of osteoporotic fractures. Whilst bone density is routinely measured to assess fracture risk, little attention is given to the assessment of fall risk. In this study we have determined the prevalence and explored relationships between fall-related risk factors and osteoporosis in women referred to our open access bone densitometry service. DESIGN: Cross-sectional study. SETTING: Teaching hospital in south-west London, UK. SUBJECTS: Older women referred for open access bone densitometry. MEASUREMENTS: Bone densitometry by dual-energy X-ray absorptiometry and fall risk assessment (visual acuity, ability to do five stand-ups without arm use and ability to perform heel-toe walking). RESULTS: Data for 558 women seen over an 18 month period were examined. Their mean age was 74.8 years (range 65-93). Fall risk and femoral neck (FN) osteoporosis increased with age, with fall-related risk factors being more prevalent than FN osteoporosis at each tertile of age. Women with both FN osteoporosis and fall-related risk factors ranged from 7% in the youngest tertile to 22% in the oldest tertile. In women with FN osteoporosis, increased fall risk was found in 37% in the youngest tertile, increasing to 63% in the oldest tertile. CONCLUSIONS: Fall-related risk factors are common in older women referred for open access bone densitometry. We recommend that both bone density and fall risk assessment, using simple screening tests for falls, are essential to determine fracture risk in older people referred for bone densitometry. Subsequent management to reduce fracture risk should be individualised for each patient. 相似文献
102.
Liver repopulation with xenogenic hepatocytes in B and T cell-deficient mice leads to chronic hepadnavirus infection and clonal growth of hepatocellular carcinoma 下载免费PDF全文
Joerg Petersen Maura Dandri Sanjeev Gupta Charles E. Rogler 《Proceedings of the National Academy of Sciences of the United States of America》1998,95(1):310-315
To investigate host and viral mechanisms determining hepadnaviral persistence and hepatocarcinogenesis, we developed a mouse model by transplanting woodchuck hepatocytes into the liver of mice that contain the urokinase-type plasminogen activator transgene (uPA) and lack mature B and T lymphocytes due to a recombination activation gene 2 (RAG-2) gene knockout. The woodchuck hepatocytes were transplanted via intrasplenic injection and were found to integrate into the recipient mouse liver cord structure. Normal adult woodchuck hepatocytes proliferated and reconstituted up to 90% of the uPA/RAG-2 mouse liver. uPA/RAG-2 mice containing woodchuck hepatocytes were infectable with woodchuck hepatitis virus (WHV) and showed WHV replication for at least 10 months with titers up to 1 × 1011 virions per ml in the peripheral blood. WHV-infected hepatocytes from chronic carrier woodchucks also established a persistent infection in uPA/RAG-2 mice after an 8- to 12-week lag period of viremia. Although WHV envelope, core, and X proteins were produced in the uPA/RAG-2 mice, no inflammatory host immune response was observed in the liver of WHV-replicating mice. A first antiviral test demonstrated a greater than four orders of magnitude drop in WHV titer in response to interferon α treatment. WHV replication was up-regulated by dexamethasone treatment. Comparison of precancerous lesions in donor woodchucks versus recipient uPA/RAG-2 mice revealed an enrichment of dysplastic precancerous hepatocytes in transplanted mice. Clonal amplification of hepatocytes from a woodchuck with hepatocellular carcinomas was demonstrated by the detection of unique WHV DNA integration patterns in hepatocellular carcinomas that arose in uPA/RAG-2 mice. In the absence of B or T cell-mediated immune responses, WHV establishes a persistent noncytotoxic infection of woodchuck hepatocytes in uPA/RAG-2 chimeric mouse livers. Further studies of the kinetics of hepadnavirus infection and replication in quiescent and proliferating hepatocytes should increase our understanding of hepadnavirus spread and aid in the design of therapies to block or cure persistent infection. 相似文献
103.
Martina Vendrame Stephanie Jackson Sana Syed Sanjeev V. Kothare Sanford H. Auerbach 《Sleep & breathing》2014,18(1):119-124
Purpose
We sought to examine the prevalence of central sleep apnea (CSA) and complex sleep apnea (CompSA) in patients with epilepsy and to examine their clinical profile, with respect to epilepsy type, etiology, medication use, and EEG abnormalities.Methods
We undertook a retrospective analysis of 719 consecutive patients with epilepsy who underwent polysomnography (PSG) at our institution between 2004 and 2011. Of the 458 patients with complete data, we excluded 42 patients with congestive heart failure or left ventricular ejection fraction <40 %. Comparison of clinical and PSG variables between the three groups were conducted with Fisher exact test and analysis of variance.Results
Out of 416 patients tested, 315 (75 %) had obstructive sleep apnea (OSA), 16 (3.7 %) had CSA, 33 (7.9 %) had CompSA. There were more males in the CSA and CompSA groups than in the OSA group (81.2, 81.8, and 59.6 %, respectively, p?=?0.04). Focal seizures were more prevalent in patients with CSA than in patients OSA or CompSA (62.5, 265, and 21.1 %, respectively, p?=?0.02).Conclusion
About 11 % of epilepsy patients have sleep-breathing disorders with central apneas, which is not higher than that in a general population. These data should be expanded with future research investigating the role of interictal, ictal, and postictal central apneas in epileptogenesis and epilepsy. 相似文献104.
105.
Hybrid procedure of bilateral pulmonary artery banding and bilateral ductal stenting in an infant with aortic atresia and interrupted aortic arch 下载免费PDF全文
Daisuke Kobayashi MD Daniel R. Turner MD Ralph E. Delius MD Sanjeev Aggarwal MD 《Catheterization and cardiovascular interventions》2014,84(7):1157-1162
We report an infant with aortic valve atresia, interrupted aortic arch, ventricular septal defect, confluent pulmonary arteries, bilateral arterial ducts, absent common carotid arteries, and anomalous coronary arteries arising from main pulmonary artery. Hybrid procedure consisting of bilateral pulmonary artery banding and bilateral arterial duct stenting was performed at 4 weeks of age. Hybrid procedure can be an alternative palliative approach in an infant with this complex cardiac anatomy. © 2014 Wiley Periodicals, Inc. 相似文献
106.
Renfang Mao Wen Bu Chad J Creighton Pingju Zheng Sanjeev Vasudevan Lei An Jinshu Yang Yi‐Jue Zhao Huiyuan Zhang Xiao‐Nan Li Pulivarthi H Rao Eastwood Leung Yong‐Jie Lu Joe W Gray Rachel Schiff Susan G Hilsenbeck C Kent Osborne Jianhua Yang Hong Zhang 《The Journal of pathology》2014,232(1):75-86
Gene amplifications in the 17q chromosomal region are observed frequently in breast cancers. An integrative bioinformatics analysis of this region nominated the MAP3K3 gene as a potential therapeutic target in breast cancer. This gene encodes mitogen‐activated protein kinase kinase kinase 3 (MAP3K3/MEKK3), which has not yet been reported to be associated with cancer‐causing genetic aberrations. We found that MAP3K3 was amplified in approximately 8–20% of breast cancers. Knockdown of MAP3K3 expression significantly inhibited cell proliferation and colony formation in MAP3K3‐amplified breast cancer cell lines MCF‐7 and MDA‐MB‐361 but not in MAP3K3 non‐amplified breast cancer cells. Knockdown of MAP3K3 expression in MAP3K3‐amplified breast cancer cells sensitized breast cancer cells to apoptotic induction by TNFα and TRAIL, as well as doxorubicin, VP‐16 and fluorouracil, three commonly used chemotherapeutic drugs for treating breast cancer. In addition, ectopic expression of MAP3K3, in collaboration with Ras, induced colony formation in both primary mouse embryonic fibroblasts and immortalized human breast epithelial cells (MCF‐10A). Combined, these results suggest that MAP3K3 contributes to breast carcinogenesis and may endow resistance of breast cancer cells to cytotoxic chemotherapy. Therefore, MAP3K3 may be a valuable therapeutic target in patients with MAP3K3‐amplified breast cancers, and blocking MAP3K3 kinase activity with a small molecule inhibitor may sensitize MAP3K3‐amplified breast cancer cells to chemotherapy. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
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110.
Deepti P. Bhat MD Lakshmi Nagaraju MD Basim I. Asmar MD Sanjeev Aggarwal MD 《Congenital heart disease》2014,9(4):E116-E120
Infective endocarditis is extremely rare in children with structurally normal hearts. The most common etiological agents are staphylococcal and streptococcal species. Nutritionally variant streptococci also classified as Abiotrophia species are a group of fastidious organisms that account for only 5% to 6% of all cases of culture‐negative infective endocarditis. Only seven cases of Abiotrophia infective endocarditis have been previously reported in children with no underlying structural heart disease. We report two cases of Abiotrophia infective endocarditis in children without any predisposing factors. Both patients presented with nonspecific symptoms leading to delay in diagnosis. While bacteriological clearance was achieved in both cases, both had a complicated course including development of brain mycotic aneurysms, splenic infarction, renal failure, and irreversible damage to the mitral valve. Both patients required surgical removal of the native mitral valve and replacement. We also present review of seven cases with similar diagnosis published previously in literature and highlight important differences. Our cases highlight special challenges in management of Abiotrophia endocarditis in pediatric patients. As the organism may not be isolated in routine culture media, may present with atypical clinical symptoms and may have a complicated course even without antibiotic failure, a high index of suspicion should be maintained in children with subacute symptoms even with no underlying structural cardiac disease. 相似文献