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61.
A major pathway by which cerebrospinal fluid (CSF) is removed from the cranium is transport through the cribriform plate in association with the olfactory nerves. CSF is then absorbed into lymphatics located in the submucosa of the olfactory epithelium (olfactory turbinates). In an attempt to provide a quantitative measure of this transport, 125I-human serum albumin (HSA) was injected into the lateral ventricles of adult Fisher 344 rats. The animals were killed at 10, 20, 30, 40, and 60 min after injection, and tissue samples, including blood (from heart puncture), skeletal muscle, spleen, liver, kidney, and tail were excised for radioactive assessment. The remains were frozen. To sample the olfactory turbinates, angled coronal tissue sections anterior to the cribriform plate were prepared from the frozen heads. The average concentration of 125I-HSA was higher in the middle olfactory turbinates than in any other tissue with peak concentrations achieved 30 min after injection. At this point, the recoveries of injected tracer (percent injected dose/g tissue) were 9.4% middle turbinates, 1.6% blood, 0.04% skeletal muscle, 0.2% spleen, 0.3% liver, 0.3% kidney, and 0.09% tail. The current belief that arachnoid projections are responsible for CSF drainage fails to explain some important issues related to the pathogenesis of CSF disorders. The rapid movement of the CSF tracer into the olfactory turbinates further supports a role for lymphatics in CSF absorption and provides the basis of a method to investigate the novel concept that diseases associated with the CSF system may involve impaired lymphatic CSF transport.  相似文献   
62.
We have developed an oat cell-free apoptosis system to investigate the execution mechanisms of plant apoptosis. Cell extracts derived from oat tissues undergoing toxin (victorin)-induced apoptosis caused nuclear collapse and internucleosomal DNA fragmentation in isolated nuclei. Pharmacological studies revealed that cysteine protease, which is E-64-sensitive but insensitive to caspase-specific inhibitors, is a crucial component in the morphological change of isolated nuclei, and that nuclease and the cysteine protease act cooperatively to induce the apoptotic DNA laddering. Interestingly, this finding is contrasted with those in well-studied animal cell-free systems in which an apoptotic endonuclease is solely responsible for the DNA fragmentation.  相似文献   
63.
Cancer‐upregulated gene 2 (CUG2) was originally identified as a potential oncogene commonly up‐regulated in various human cancers. Recently, CUG2 was also identified as a new member of a centromere protein complex, important in the formation of a functional kinetochore complex. Presently, we report the pro‐apoptotic effect of CUG2 when this gene was overexpressed in the SKOV‐3 human ovarian cancer cell line. Apoptotic cell death mediated by CUG2 overexpression was independently demonstrated using cell viability determination, flow cytometry analysis, chromosome fragmentation assay, and the cleavage of the death substrate poly(ADP‐ribose) polymerase. Moreover, activation of caspase‐3 and ‐8 and the cytoplasmic translocation of mitochondrial cytochrome c were evident upon CUG2 expression. Apoptotic cell death was also observed during early development of zebrafish when CUG2 was overexpressed in zebrafish embryo. We propose that high expression of CUG2 induces apoptotic cell death. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
64.
Alzheimer’s disease (AD) is characterized by progressive memory loss and cognitive function deficits. There are two major pathological hallmarks that contribute to the pathogenesis of AD which are the presence of extracellular amyloid plaques composed of amyloid-β (Aβ) and intracellular neurofibrillary tangles composed of hyperphosphorylated tau. Despite extensive research that has been done on Aβ in the last two decades, therapies targeting Aβ were not very fruitful at treating AD as the efficacy of Aβ therapies observed in animal models is not reflected in human clinical trials. Hence, tau-directed therapies have received tremendous attention as the potential treatments for AD. Tauopathies are closely correlated with dementia and immunotherapy has been effective at reducing tau pathology and improving cognitive deficits in animal models. Thus, in this review article, we discussed the pathological mechanism of tau proteins, the key factors contributing to tauopathies, and therapeutic approaches for tauopathies in AD based on the recent progress in tau-based research.  相似文献   
65.
Highlights? Two-way modulations of adipose VEGF were generated with aP2-Cre transgene ? Adipose VEGF KO reduces vasculature, increases hypoxia and inflammation in fat ? Adipose VEGF KO accelerates the development of metabolic disease in high-fat diet ? Induced adipose VEGF has opposite effect on fat and restores metabolic homeostasis  相似文献   
66.

Background

The progression of hepatic fibrosis may result in decompensated hepatic failure with cirrhosis, liver related events (LRE) such as ascites, variceal bleeding, and death after successful and timely Kasai hepatoportoenterostomy (HPE) in biliary atresia. The aim of this study is to suggest clinical benefit of the liver stiffness measurement (LSM) using transient elastography at 3 months after the Kasai operation to predict LRE.

Methods

Between January 2007 and December 2011, 69 eligible biliary atresia patients who underwent Kasai HPE and performed transient elastography before and 3 months after HPE were included. The occurrences of LRE were analyzed for all patients. All patients were divided into 2 groups (with and without LRE) for comparison. Multivariate analysis was used to detect the independent risk factors of LRE. The area under the receiver operation characteristics curve (AUROC) was used to establish the LSM optimal cutoff value of 3 months after Kasai operation in predicting LRE.

Results

LSM value, aminotransferase, albumin, bilirubin, and PT-INR significantly differed among the two groups. Multivariate analysis demonstrated LSM value as the most powerful independent factor of the development of LRE. The cut-off value of 19.9 kPa was calculated to be optimal for predicting LRE development with total sensitivity and specificity of 1.804. AUROC resulted in 0.943, with sensitivity of 85.3% and specificity of 95.2%.

Conclusions

The LSM value of 3 months after Kasai HPE can be a useful predictor of LRE development.  相似文献   
67.
We cloned in E. coli the whole 17 nif genes (nifQ-J) of Klebsiella oxytoca NG13 using pBR322 as a vector, and constructed a recombinant plasmid, pNOW25 (nif+, Apr, 42.6 kb). A non nif DNA fragment was deleted from the plasmid with XhoI, and a smaller plasmid, pNOK31 (nif+, Apr, 31.1 kb), was reconstructed.

We constructed the restriction map of the cloned nif genes. The map was the same as that of the K. pneumoniae M5a1 nif genes as to the EcoRI, HindIII, BamHI and XhoI sites, but differed considerably in the PstI, SalI and BglII sites.

E. coli KO60 containing pNOW25 or pNOK31 can grow on a N-free medium. The acetylene reduction activities of KO60 (pNOW25) and KO60 (pNOK31) were 280 nmol and 390 nmol/48 hr per 7 ml of N-free liquid medium, whereas the activity of K. oxytoca NG13 was 3800 nmol. Thus, the expressed activity of the nif system of K. oxytoca is rather low in E. coli even if the nif genes are cloned on a multicopy plasmid.  相似文献   
68.
69.
OBJECTIVE: To investigate estrogen receptor (ER) and progesterone receptor (PR) levels in imprint specimens obtained at breast surgery and to compare their correlation with that of standard methods. STUDY DESIGN: Imprint specimens for cytology were obtained from 101 mass-forming lesions in 66 patients, and specimens were frozen in liquid nitrogen for later assay. The imprint specimens were immunocytochemically (ICC) stained by monoclonal antibody to ER or PR; diaminobenzidine-stained cell nuclei in clusters were regarded as positive. Tissue specimens were assayed by the standard method of dextran-coated charcoal assay (DCC) and enzyme immunoassay. RESULTS: Forty-five primary breast cancer lesions, 2 contralateral breast cancer, 49 dissected nodes and 5 benign breast lesions were collected. The correlation between DCC and ICC was 81% (82/101) for ER and 74% (66/101) for PR. That between EIA and ICC was 88% (88/99) for ER and 80% (79/100) for PR, higher than that between DCC and ICC for ER and PR. CONCLUSION: ICC assessment of ER or PR on imprint cytology is a promising clinical test with an acceptable correlation.  相似文献   
70.
Reexpansion of a collapsed lung increases the microvascular permeability and causes reexpansion pulmonary edema. Neutrophils and their products have been implicated in the development of this phenomenon. The small GTP-binding proteins Rho and its target Rho-kinase (ROCK) regulate endothelial permeability, although their roles in reexpansion pulmonary edema remain unclear. We studied the contribution of ROCK to pulmonary endothelial and epithelial permeability in a rabbit model of this disorder. Endothelial and epithelial permeability was assessed by measuring the tissue-to-plasma (T/P) and bronchoalveolar lavage (BAL) fluid-to-plasma (B/P) ratios with (125)I-labeled albumin. After intratracheal instillation of (125)I-albumin, epithelial permeability was also assessed from the plasma leak (PL) index, the ratio of (125)I-albumin in plasma/total amount of instilled (125)I-albumin. T/P, B/P, and PL index were significantly increased in the reexpanded lung. These increases were attenuated by pretreatment with Y-27632, a specific ROCK inhibitor. However, neutrophil influx, neutrophil elastase activity, and malondialdehyde concentrations in BAL fluid collected from the reexpanded lung were not changed by Y-27632. In endothelial monolayers, Y-27632 significantly attenuated the H(2)O(2)-induced increase in permeability and mitigated the morphological changes in the actin microfilament cytoskeleton of endothelial cells. These in vivo and in vitro observations suggest that the Rho/ROCK pathway contributes to the increase in alveolar barrier permeability associated with reexpansion pulmonary edema.  相似文献   
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