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It has been demonstrated that a small percentage (approximately 15%) of glioblastomas (GBM) presents an oligodendroglial component with a variable frequency of chromosome 1p and 19q deletions, the genetic alteration related to chemotherapy response and longer survival in oligodendrogliomas. There is a growing interest in investigating 1p and 19q losses in hybrid gliomas and their impact on prognosis. A series of 88 GBMs was investigated regarding 1p and/or 19q losses, 24 with oligodendroglioma-like areas, using quantitative microsatellite analysis and/or fluorescent in situ hybridization. When present, the oligodendroglial and astrocytic components were independently investigated. Clinical data, histology, and 1p/19q status were correlated. Tumors with oligodendroglial components showed three cases each of 1p or 19q loss and one with combined 1p/19q loss. No difference in 1p or 19q status was observed between the oligodendroglial and astrocytic components. Conventional GBM demonstrated isolated 1p loss in four cases and 19q loss in five. No association was seen between 1p/19q status and histology. Deletions at 1p and/or 19q were infrequent in GBMs with oligodendroglial components. Despite the hybrid phenotype, the pattern of genetic changes at 1p and 19q was not different from that usually observed in conventional GBMs, nor did it show any correlation with survival.  相似文献   
76.
Early endosome antigen 1 (EEA1) is a target autoantigen in patients diagnosed with neurological and other autoimmune conditions. Eighteen of 65 sera (28%) that displayed a vesicular cytoplasmic staining pattern also immunoprecipitated the recombinant EEA1. These 18 sera were selected for further clinical, serological and epitope mapping studies. Thirty-six percent of the 18 patients had neurological diseases. Seventeen sera (94%) reacted with the partial length EEA1 constructs that included the C-terminal zinc finger (+FYVE) and the methyl accepting domain (LeuMA: amino acids 82-1411) in an addressable laser bead assay suggesting that the assay may be used for rapid laboratory detection of anti-EEA1 antibodies. Three of seven sera selected for epitope mapping studies bound to EEA1 peptides represented by amino acids 1096-1125, and two reacted with peptides represented by amino acids 1296-1320. One serum reacted only with the C-terminal peptide 1096-1125. The remaining serum reacted with other EEA1 epitopes. This data was supported by the observations that all the sera immunoprecipitated the C-terminal +FYVE (EEA1 1064-1411) construct, a peptide that also contained the linear epitopes 1096-1140. The limited epitope mapping studies suggest that the sera from patients with non-neurological diseases recognized epitopes in the central and C-terminal EEA1 domains, whereas the patients with neurological disease recognized a more restricted set of epitopes in the C-terminal.  相似文献   
77.
Xia JQ  Lo JY  Yang K  Floyd CE  Boone JM 《Medical physics》2008,35(5):1950-1958
Dedicated breast computed tomography (CT) imaging possesses the potential for improved lesion detection over conventional mammograms, especially for women with dense breasts. The breast CT images are acquired with a glandular dose comparable to that of standard two-view mammography for a single breast. Due to dose constraints, the reconstructed volume has a non-negligible quantum noise when thin section CT slices are visualized. It is thus desirable to reduce noise in the reconstructed breast volume without loss of spatial resolution. In this study, partial diffusion equation (PDE) based denoising techniques specifically for breast CT were applied at different steps along the reconstruction process and it was found that denoising performed better when applied to the projection data rather than reconstructed data. Simulation results from the contrast detail phantom show that the PDE technique outperforms Wiener denoising as well as adaptive trimmed mean filter. The PDE technique increases its performance advantage relative to Wiener techniques when the photon fluence is reduced. With the PDE technique, the sensitivity for lesion detection using the contrast detail phantom drops by less than 7% when the dose is cut down to 40% of the two-view mammography. For subjective evaluation, the PDE technique was applied to two human subject breast data sets acquired on a prototype breast CT system. The denoised images had appealing visual characteristics with much lower noise levels and improved tissue textures while maintaining sharpness of the original reconstructed volume.  相似文献   
78.
Cellular senescence and organismal aging   总被引:2,自引:0,他引:2  
Cellular senescence, first observed and defined using in vitro cell culture studies, is an irreversible cell cycle arrest which can be triggered by a variety of factors. Emerging evidence suggests that cellular senescence acts as an in vivo tumor suppression mechanism by limiting aberrant proliferation. It has also been postulated that cellular senescence can occur independently of cancer and contribute to the physiological processes of normal organismal aging. Recent data have demonstrated the in vivo accumulation of senescent cells with advancing age. Some characteristics of senescent cells, such as the ability to modify their extracellular environment, could play a role in aging and age-related pathology. In this review, we examine current evidence that links cellular senescence and organismal aging.  相似文献   
79.

Research question

Previous studies of aromatase inhibitors on male infertility have focused on men with low testosterone–oestradiol ratio of less than 10. Can aromatase inhibitors improve spermatogenesis in men with idiopathic male infertility with normal testosterone–oestradiol ratio?

Design

Prospective study of men with idiopathic severe oligozoospermia (sperm concentration <5 million/ml) carried out between February 2015 and March 2017. The objective was to assess if semen-analysis parameters improved after treatment with letrozole. Secondary objectives were to monitor the safety of letrozole in men, and to measure the alterations in serum FSH, LH, oestradiol and testosterone levels.

Results

Fifteen men with normal testosterone–oestradiol ratio (>10) were treated with letrozole 2.5 mg daily for 4 months. This produced a 5.5-fold increase in sperm concentration (P?=?0.0068). All men had increased total serum testosterone and suppressed oestradiol levels after treatment, thus raising the overall testosterone–oestradiol ratio (P < 0.0001). Adverse effects from letrozole were relatively minor and included loss of libido (54%), headaches (25%), fatigue (21%), weakness (13%), loss of hair (8%) and dry mouth (8%).

Conclusions

Letrozole improves sperm concentration and increases testosterone–oestradiol ratio for men with oligozoospermia who have normal testosterone–oestradiol ratio; its role in the treatment of male infertility may be extended to this group of patients. In addition, it is a relatively well-tolerated drug with no serious adverse effects.  相似文献   
80.

Background  

The aim of this study is to assess skin strength in MWL patients relative to control cosmetic abdominoplasty patients biophysically, biochemically, and histologically. Growing success of weight loss programs has brought about an increase in the MWL population. Skin quality is thought to be impaired by MWL, but there are no compelling studies that have fully addressed the structural mechanisms involved.  相似文献   
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