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31.
Various guidelines have been proposed regarding which portions of a surgical gown may be considered sterile. Unfortunately, the validity of these recommendations has not been definitively established. We therefore evaluated gown sterility after major spinal surgery to assess the legitimacy of these guidelines. We used sterile culture swabs to obtain samples of gown fronts at 6-inch increments and at the elbow creases of 50 gowns at the end of 29 spinal operations. Another 50 gowns were swabbed immediately after they were applied to serve as negative controls. Bacterial growth was assessed using semiquantitative plating techniques on a nonselective, broad-spectrum media. Contamination was observed at all locations of the gown with rates ranging from 6% to 48%. Compared with the negative controls, the contamination rates were greater at levels 24 inches or less and 48 inches or more relative to the ground and at the elbow creases. The section between the chest and operative field had the lowest contamination rates. Based on these results, we consider the region between the chest and operative field to be the most sterile and any contact with the gown outside this area, including the elbow creases, should be avoided to reduce the risk of infection. Each author certifies that he or she has no commercial associations (eg, consultancies, stock ownership, equity interest, patent/licensing arrangements, etc) that might pose a conflict of interest in connection with the submitted article. Each author certifies that his or her institution has approved the human protocol for this investigation, that all investigations were conducted in conformity with ethical principles of research.  相似文献   
32.
Infantile neuronal ceroid lipofuscinosis (INCL) is caused by deficiency of the lysosomal enzyme, palmitoyl protein thioesterase 1 (PPT1). We have investigated the onset and progression of pathological changes in Ppt1 deficient mice (Ppt1-/-) and the development of their seizure phenotype. Surprisingly, cortical atrophy and neuron loss occurred only late in disease progression but were preceded by localized astrocytosis within individual thalamic nuclei and the progressive loss of thalamic neurons that relay different sensory modalities to the cortex. This thalamic neuron loss occurred first within the visual system and only subsequently in auditory and somatosensory relay nuclei or the inhibitory reticular thalamic nucleus. The loss of granule neurons and GABAergic interneurons followed in each corresponding cortical region, before the onset of seizure activity. These findings provide novel evidence for successive neuron loss within the thalamus and cortex in Ppt1-/- mice, revealing the thalamus as an important early focus of INCL pathogenesis.  相似文献   
33.
Isham CR  Tibodeau JD  Jin W  Xu R  Timm MM  Bible KC 《Blood》2007,109(6):2579-2588
Chaetocin, a thiodioxopiperazine natural product previously unreported to have anticancer effects, was found to have potent antimyeloma activity in IL-6-dependent and -independent myeloma cell lines in freshly collected sorted and unsorted patient CD138(+) myeloma cells and in vivo. Chaetocin largely spares matched normal CD138(-) patient bone marrow leukocytes, normal B cells, and neoplastic B-CLL (chronic lymphocytic leukemia) cells, indicating a high degree of selectivity even in closely lineage-related B cells. Furthermore, chaetocin displays superior ex vivo antimyeloma activity and selectivity than doxorubicin and dexamethasone, and dexamethasone- or doxorubicin-resistant myeloma cell lines are largely non-cross-resistant to chaetocin. Mechanistically, chaetocin is dramatically accumulated in cancer cells via a process inhibited by glutathione and requiring intact/unreduced disulfides for uptake. Once inside the cell, its anticancer activity appears mediated primarily through the imposition of oxidative stress and consequent apoptosis induction. Moreover, the selective antimyeloma effects of chaetocin appear not to reflect differential intracellular accumulation of chaetocin but, instead, heightened sensitivity of myeloma cells to the cytotoxic effects of imposed oxidative stress. Considered collectively, chaetocin appears to represent a promising agent for further study as a potential antimyeloma therapeutic.  相似文献   
34.
Although extremely rare, the primitive lung hemangiopericytoma in adults is similar to hemangiopericytomas with other soft tissue localizations. Although generally benign and curable after radical surgery, it might also have a malignant clinical course with dissemination in both lungs, infiltration of vital organs (heart, pulmonary artery), extension to the adjacent tissues, and even pulmonary metastases. The treatment of choice is the complete tumor resection with negative surgical margins after excision. Certain histologic features might indicate a malignant potential. The clinical outcome of patients is variable: some are cured after radical surgery and others might present relapse and recurrences that necessitate a second intervention, radiation therapy, and/or chemotherapy. Over the years, the conventionally-defined hemangiopericytoma concept has evolved because of the nonspecific histologic growth pattern (characteristic monotonous appearance, moderate or high cellularity, and a well-developed branching vascular pattern) shared by numerous, unrelated benign or malignant lesions. Hemangiopericytoma is no longer considered a specific entity but rather as a characteristic growth pattern; in the heterogeneous group of hemangiopericytoma-like neoplasms, many lesion categories have been individualized and defined. We report an uncommon case of primitive lung tumor exhibiting hemangiopericytoma-like features, with an aggressive, fatal clinical course. Because of the major histologic overlap between solitary fibrous tumor and hemangiopericytoma and lack of clear classification criteria, we encountered difficulty in including this case in a known clinical entity; primitive solitary fibrous tumor of the lung, which mimics lung hemangiopericytoma, seemed to be the most plausible diagnosis. We discuss the case particularities and the radiologic and pathologic correlations.  相似文献   
35.
Introduction:  The neuronal ceroid lipofuscinoses (NCL) are progressive neurodegenerative disorders with onset from infancy to adulthood that are manifested by blindness, seizures and dementia. In infantile NCL (INCL), a mutation in the palmitoyl protein thioesterase (PPT1) gene results in loss of PPT1 activity and lysosomal accumulation of autofluorescent proteolipid in the brain and other tissues. We have generated a PPT1 knockout mouse model of INCL (PPT1–/–) and characterized pathological changes in the CNS of these mice, which die by 8 months of age.
Results:  7-month-old PPT1–/– exhibited NCL-like pathology with prominent accumulation of autofluorescent lipopigment throughout the CNS, together with pronounced cerebral atrophy. Staining for phenotypic markers normally present in subpopulations of interneurons in the cortex and hippocampus revealed progressive loss of staining in the cortex and hippocampus, with persisting interneurons exhibiting pronounced hypertrophy and abnormal dendritic morphology.
Conclusions:  Taken together with our findings in the other mouse models of NCL and preliminary data from NCL patient derived tissue, these results provide further substantive evidence for the involvement of interneurons in the NCLs.
Acknowledgements:  Supported by The Batten's Disease Support and Research Association, The Natalie Fund, The Remy Fund; Batten's Disease Family Association.  相似文献   
36.
Despite concerted prevention efforts, young South African women remain at the epicenter of the HIV epidemic. Although these women have grown up in a community powerfully affected by HIV, systematic investigation into how this “second generation” of HIV-affected youth navigates HIV risk is lacking. This study qualitatively explored a complex interplay of factors influencing HIV risk among young pregnant women in KwaZulu-Natal, South Africa. We conducted in-depth interviews with 35 pregnant women (22 HIV-uninfected and 13 HIV-infected) aged 18–21, 18 healthcare providers, and focus groups with 19 community stakeholders. Among the young women, HIV knowledge was high, and many reported taking some action to prevent pregnancy or HIV; however, these efforts were not routinely implemented. Themes related to HIV acquisition risk from all participants were organized using a socioecological framework and revolved around individual and developmental experiences (personal experience with HIV, perceived invincibility), family barriers (lack of adult supervision, pressure to leave school), relational barriers (lack of disclosure and partner communication, “burn out” around attempts to discuss condom use with partners, overdependence on partners), community-level barriers (township environment, lack of structured activities), and social barriers (poverty, HIV-related stigma). Some novel concepts emerged from the data, including an understanding of how overdependence on the romantic relationship may develop. Current HIV prevention efforts, including traditional HIV counseling and testing, condom distribution, and biomedical agents for HIV prevention, are unlikely to be effective without a broader, ecological up-to-date understanding of the evolving, intertwined, and complex constellation of factors that drive HIV risk behavior in this high-risk population.  相似文献   
37.
Black women living with HIV/AIDS (LWHA) are a subgroup with the highest growing rates of HIV infection in the United States. Stigma and co-occurring mental and physical health problems have been reported among Black women LWHA, and research on the benefits of social and religious support, often major protective factors among Black women, has been met with mixed findings. The current study examined the relation between anticipated HIV stigma and mental and physical health symptoms and risk and protective factors (discrimination, coping, social support) among Black women LWHA (N = 220). Results showed that greater anticipated stigma was significantly related to poorer mental health status, greater discrimination, and greater use of negative coping strategies. Stigma was not related to physical health, perceived social support or use of positive coping strategies. This study lends support to the need for psychosocial interventions that reduce anticipated stigma among individuals LWHA, particularly Black women LWHA.  相似文献   
38.

Background  

Noncemented revision arthroplasty is often complicated by the presence of bone implant gaps that reduce initial stability and biologic fixation. Demineralized bone matrix has osteoinductive properties and therefore the potential to enhance gap healing and porous implant fixation.  相似文献   
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