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91.
92.
BACKGROUND: Extraskeletal myxoid chondrosarcoma is a rare soft tissue tumor of the extremities. Since it usually lacks obvious chondroid differentiation on light microscopy, it needs to be distinguished from other myxoid soft tissue sarcomas. CASE REPORT: The diagnosis of extraskeletal myxoid chondrosarcoma was made on fine needle aspiration in a patient with a swelling in the right calf. Cellular myxoid fragments having round to oval cells with grooved nuclei arranged in a cordlike pattern suggested chondroid differentiation. The diagnosis was confirmed by histopathology. CONCLUSION: Fine needle aspiration cytology can be diagnostic of extraskeletal myxoid chondrosarcoma even in the absence of obvious chondroid differentiation. 相似文献
93.
Structurally and functionally distinct mouse hsp70 family members Mot-1 and Mot-2 proteins are encoded by two alleles. 总被引:1,自引:0,他引:1
The mouse mortalin proteins Mot-1 and Mot-2 differ by two amino acids in their carboxy-terminus. These proteins are differentially localized in the cell cytoplasm and have contrasting biological activities. The genetic relationship between Mot-1 and Mot-2 was deciphered by mouse family analyses. Mot-1 and Mot-2 segregated in F1 and F2 progeny, providing direct evidence that the two proteins are encoded by two alleles. 相似文献
94.
The lateral geniculate nuclear complex of albino rats was investigated with respect to the development of neurotransmitters/neuromodulators
such as glutamate, cholecystokinin and vasoactive intestinal polypeptide at gestational day 18, various postnatal age periods
and in the adult using immunohistochemical methods. The study shows the unequivocal presence of and the sequential changes
in the profile of glutamate while cholecystokinin and vasoactive intestinal polypeptide are not demonstrable at any of the
age periods. Glutamate is seen both in the cells and fibres from 40 postnatal day onwards and immunoreactivity is more intense
in the adult. The findings are discussed with relevance to the role of neurotransmitters in development. 相似文献
95.
Control of lipid composition of membranes is crucial to ensure normal cellular functions. Saccharomyces cerevisiae has two different phosphatidylserine decarboxylase enzymes (Psd1 and Psd2) that catalyze formation of phosphatidylethanolamine. The mitochondrial Psd1 provides roughly 70% of the phosphatidylethanolamine (PE) biosynthesis in the cell with Psd2 carrying out the remainder. Here, we demonstrate that loss of Psd2 causes cells to acquire sensitivity to cadmium even though Psd1 remains intact. This cadmium sensitivity results from loss of normal activity of a vacuolar ATP-binding cassette transporter protein called Ycf1. Measurement of phospholipid levels indicates that loss of Psd2 causes a specific reduction in vacuolar membrane PE levels, whereas total PE levels are not significantly affected. The presence of a phosphatidylinositol transfer protein called Pdr17 is required for Psd2 function and normal cadmium tolerance. We demonstrate that Pdr17 and Psd2 form a complex in vivo that seems essential for maintenance of vacuolar PE levels. Finally, we refine the localization of Psd2 to the endosome arguing that this enzyme controls vacuolar membrane phospholipid content by regulating phospholipids in compartments that will eventually give rise to the vacuole. Disturbance of this regulation of intracellular phospholipid balance leads to selective loss of membrane protein function in the vacuole. 相似文献
96.
97.
Rationale
Oxygen therapy improves survival and function in severely hypoxemic chronic obstructive pulmonary disease (COPD) patients based on two landmark studies conducted over 40 years ago. We hypothesize that oxygen users in the current era may be very different. We examined trends and subject characteristics associated with oxygen therapy use from 2001–2010 in the United States.Methods
We examined Medicare beneficiaries with COPD who received oxygen from 2001 to 2010. COPD subjects were identified by: 1) ≥2 outpatient visits >30 days apart within one year with an encounter diagnosis of COPD; or 2) an acute care hospitalization with COPD as the primary or secondary discharge diagnosis. Oxygen therapy and sustained oxygen therapy were defined as ≥1 and ≥11 claims for oxygen, respectively, in the durable medical equipment file in a calendar year. Primary outcome measures were factors associated with oxygen therapy and sustained oxygen therapy over the study period.Results
Oxygen therapy increased from 33.7% in 2001 to 40.5% in 2010 (p-value of trend <0.001). Sustained oxygen therapy use increased from 19.5% in 2001, peaked in 2008 to 26.9% and declined to 18.5% in 2010. The majority of subjects receiving oxygen therapy and sustained oxygen therapy were female. Besides gender, factors associated with any oxygen use or sustained oxygen therapy were non-Hispanic white race, low socioeconomic status and ≥2 comorbidities.Conclusions
Any oxygen use among fee-for service Medicare beneficiaries with COPD is high. Current users of oxygen are older females with multiple comorbidities. Decline in sustained oxygen therapy use after 2008 may be related to reimbursement policy change. 相似文献98.
Sumbul Firdaus Anupam Dhasmana Vandana Srivastava Tasneem Bano Afreen Fatima Qazi Mohammad Sajid Jamal Roshan Jahan Gulshan Wadhwad Mohtashim Lohani 《Bioinformation》2015,11(3):122-126
Fullerenes have attracted considerable attention due to their unique chemical structure and potential applications which has
opened wide venues for possible human exposure to various fullerene types. Therefore, in depth knowledge of how fullerene may
interfere with various cellular processes becomes quite imperative. The present study was designed to investigate how the
presence of fullerene affect the binding of DNA with different enzymes involved in replication process. Different fullerenes were
first docked with DNA and then binding scores of different enzymes was analyzed with fullerene docked DNA. C30, C40 & C50
once docked with DNA, reduced the binding score of primase, whereas no significant change in the binding score was observed
with the helicase, ssb protein, dna pol δ, dna pol ε, ligase, DNA clamp, and topoisomerases. On the contrast, the binding score of
RPA14 decreases in fluctuating manner while interacting with increasing molecular weight of fullerene bound single-stranded
DNA complex. The study revealed the affect of fullerene family interacting with DNA on the binding pattern of enzymes involved
in replication process. Study suggests that the presence of most of fullerenes may not affect the activity of these enzymes necessary
for replication process whereas C30, C40 & C50 may disrupt the activity of primase, (strating point for DNA polymerase) its
docking score decreases from 13820 to 10702. 相似文献
99.
Cheung CT Singh R Yoon AR Hasan MK Yaguchi T Kaul SC Yun CO Wadhwa R 《Cell death and differentiation》2011,18(4):589-601
Collaborator of ARF (CARF) was cloned as an ARF-interacting protein and shown to regulate the p53-p21(WAF1)-HDM2 pathway, which is central to tumor suppression via senescence and apoptosis. We had previously reported that CARF inhibition in cancer cells led to polyploidy and caspase-dependent apoptosis, however, the mechanisms governing this phenomenon remained unknown. Thus, we examined various cell death and survival pathways including the mitochondrial stress, ataxia telangiectasia mutated (ATM)-ATR, Ras-MAP kinase and retinoblastoma cascades. We found that CARF is a pleiotropic regulator with widespread effects; its suppression affected all investigated pathways. Most remarkably, it protected the cells against genotoxicity; CARF knockdown elicited DNA damage response as evidenced by increased levels of phosphorylated ATM and γH2AX, leading to induction of mitotic arrest and eventual apoptosis. We also show that the CARF-silencing-induced apoptosis in vitro translates to in vivo. In a human tumor xenograft mouse model, treatment of developing tumors with short hairpin RNA (shRNA) against CARF via an adenovirus carrier induced complete suppression of tumor growth, suggesting that CARF shRNA is a strong candidate for an anticancer reagent. We demonstrate that CARF has a vital role in genome preservation and tumor suppression and CARF siRNA is an effective novel cancer therapeutic agent. 相似文献
100.
Wesley S. Bond Lalita Wadhwa Laszlo Perlaky Rebecca L. Penland Mary Y. Hurwitz Richard L. Hurwitz Patricia Ch��vez-Barrios 《Journal of visualized experiments : JoVE》2011,(54)
Culturing retinoblastoma tumor cells in defined stem cell media gives rise to primary tumorspheres that can be grown and maintained for only a limited time. These cultured tumorspheres may exhibit markedly different cellular phenotypes when compared to the original tumors. Demonstration that cultured cells have the capability of forming new tumors is important to ensure that cultured cells model the biology of the original tumor. Here we present a protocol for propagating human retinoblastoma tumors in vivo using Rag2-/- immune deficient mice. Cultured human retinoblastoma tumorspheres of low passage or cells obtained from freshly harvested human retinoblastoma tumors injected directly into the vitreous cavity of murine eyes form tumors within 2-4 weeks. These tumors can be harvested and either further passaged into murine eyes in vivo or grown as tumorspheres in vitro. Propagation has been successfully carried out for at least three passages thus establishing a continuing source of human retinoblastoma tissue for further experimentation. Wesley S. Bond and Lalita Wadhwa are co-first authors. 相似文献