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991.
992.
Recent evidences show that osthole possesses anti-inflammatory properties and protective effects following shock-like states, but the mechanism of these effects remains unknown. The p38 mitogen-activated protein kinase (p38 MAPK) pathway exerts anti-inflammatory effects in injury. The aim of this study was to investigate whether p38 MAPK plays any role in the osthole-mediated attenuation of hepatic injury after trauma-hemorrhage. Male Sprague-Dawley rats underwent trauma-hemorrhage (mean blood pressure maintained at approximately 35–40 mmHg for 90 minutes), followed by fluid resuscitation. During resuscitation, a single dose of osthole (3 mg/kg, intravenously) with and without a p38 MAPK inhibitor SB-203580 (2 mg/kg, intravenously), SB-203580 or vehicle was administered. Plasma alanine aminotransferase (ALT) with aspartate aminotransferase (AST) concentrations and various hepatic parameters were measured (n = 8 rats/group) at 24 hours after resuscitation. The results showed that trauma-hemorrhage increased hepatic myeloperoxidase activity, intercellular adhesion molecule-1 and interleukin-6 levels, and plasma ALT and AST concentrations. These parameters were significantly improved in the osthole-treated rats subjected to trauma-hemorrhage. Osthole treatment also increased hepatic phospho-p38 MAPK expression compared with vehicle-treated trauma-hemorrhaged rats. Co-administration of SB-203580 with osthole abolished the osthole-induced beneficial effects on the above parameters and hepatic injury. These results suggest that the protective effect of osthole administration on alleviation of hepatic injury after trauma-hemorrhage, which is, at least in part, through p38 MAPK-dependent pathway.  相似文献   
993.

Purpose

To determine the optimal standardized uptake value (SUV) of 18F-fluorodeoxyglucose (18F-FDG) for positron emission tomography (PET) imaging, at which the PET-defined gross tumor volume (GTVPET) best matches with the pathological volume (GTVPATH) in the cervical cancer.

Materials and Methods

Ten patients with the cervical cancer who underwent surgery were enrolled in this study. The excised specimens were processed for whole-mount serial sections and H-E staining. The tumor borders were outlined in sections under a microscope, histopathological images were scanned and the GTVPATH calculated. The GTVPET was delineated automatically by using various percentages relative to the maximal SUV and absolute SUV. The optimal threshold SUV was further obtained as the value at which the GTVPET best matched with the GTVPATH.

Results

An average of 85±10% shrinkage of tissue was observed after the formalin fixation. The GTVPATH was 13.38±2.80 cm3 on average. The optimal threshold on percentile SUV and absolute SUV were 40.50%±3.16% and 7.45±1.10, respectively. The correlation analysis showed that the optimal percentile SUV threshold was inversely correlated with GTVPATH (p<0.05) and tumor diameter (p<0.05). The absolute SUV was also positively correlated with SUVmax (p<0.05).

Conclusion

The pathological volume could provide the more accurate tumor volume. The optimal SUV of FDG for PET imaging by use of GTVPATH as standard for cervical cancer target volume delineation was thus determined in this study, and more cases are being evaluated to substantiate this conclusion.  相似文献   
994.

Background

Although transfusion-transmitted infection of hepatitis B virus (HBV) threatens the blood safety of China, the nationwide circumstance of HBV infection among blood donors is still unclear.

Objectives

To comprehensively estimate the prevalence of HBsAg positive and HBV occult infection (OBI) among Chinese volunteer blood donors through bayesian meta-analysis.

Methods

We performed an electronic search in Pub-Med, Web of Knowledge, Medline, Wanfang Data and CNKI, complemented by a hand search of relevant reference lists. Two authors independently extracted data from the eligible studies. Then two bayesian random-effect meta-analyses were performed, followed by bayesian meta-regressions.

Results

5957412 and 571227 donors were identified in HBsAg group and OBI group, respectively. The pooled prevalence of HBsAg group and OBI group among donors is 1.085% (95% credible interval [CI] 0.859%∼1.398%) and 0.094% (95% CI 0.0578%∼0.1655%). For HBsAg group, subgroup analysis shows the more developed area has a lower prevalence than the less developed area; meta-regression indicates there is a significant decreasing trend in HBsAg positive prevalence with sampling year (beta = −0.1202, 95% −0.2081∼−0.0312).

Conclusion

Blood safety against HBV infection in China is suffering serious threats and the government should take effective measures to improve this situation.  相似文献   
995.
Chronic cerebral hypoperfusion (CCH) is a common pathophysiological state that usually occurs in conditions such as vascular dementia and Alzheimer''s disease, both of which are characterized by cognitive impairment. In previous studies we found that learning capacity and memory were gradually impaired with CCH, which altered the expression of synaptophysin, microtubule associated protein-2, growth associated protein-43, brain-derived neurotrophic factor, nerve growth factor, N-methyl-D-aspartate receptor subunit 1, cAMP response element-binding protein and tau hyperphosphorylation in the hippocampus. However, the molecular basis of cognitive impairment in CCH remains obscure. Here we explore the hypothesis that the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) signal pathway is involved in this type of cognitive impairment. In order to determine if the expression of PI3K, Akt and phosphorylated Akt (p-Akt) proteins are altered at different stages of CCH with differing levels of cognitive impairment. we performed permanent, bilateral occlusion of the common carotid arteries (2-VO) to induce CCH. Adult male SD rats were randomly divided into sham-operated group, 2-VO 1 week group, 2-VO 4 weeks group and 2-VO 8 weeks group. Behavior tests were utilized to assess cognitive abilities, while western blots were utilized to evaluate protein expression. Rats in the 2-VO groups spent less time exploring novel objects than those in the sham-operated group, and the discrimination ratio of the 2-VO 8 weeks group and the sham-operated group were higher than chance (0.50). Escape latencies in the Morris water maze task in the 2-VO 1 week group were longer than those in the sham-operated group on day 4 and day 5, while escape latencies in the 2-VO 4 weeks group were longer than those in the sham-operated group from day 3 to day 5. Escape latencies in 2-VO 8 weeks group were longer than those in the sham-operated group from day 2 to day 5. NE (northeast) square swimming times in the 2-VO 1 week group, 2-VO 4 weeks group and 2-VO 8 weeks group were shorter than that in the sham-operated group. Western blotting showed that the PI3K expression in the 2-VO 1 week group was lower than that in sham-operated group, while p-Akt expression in the 2-VO 8 weeks group was higher than that in the sham-operated group. There was a linear relationship between the PI3K expression and the discrimination ratio, as well as a linear relationship between the PI3K and NE square swimming time. Thus, we propose that the PI3K/Akt signal pathway is an important cell pathway that is associated with the cognitive impairment following CCH.  相似文献   
996.
Gene/protein recognition and normalization is an important preliminary step for many biological text mining tasks. In this paper, we present a multistage gene normalization system which consists of four major subtasks: pre-processing, dictionary matching, ambiguity resolution and filtering. For the first subtask, we apply the gene mention tagger developed in our earlier work, which achieves an F-score of 88.42% on the BioCreative II GM testing set. In the stage of dictionary matching, the exact matching and approximate matching between gene names and the EntrezGene lexicon have been combined. For the ambiguity resolution subtask, we propose a semantic similarity disambiguation method based on Munkres'' Assignment Algorithm. At the last step, a filter based on Wikipedia has been built to remove the false positives. Experimental results show that the presented system can achieve an F-score of 90.1%, outperforming most of the state-of-the-art systems.  相似文献   
997.
A six-day experiment was conducted to estimate the relative bioavailability values (RBV) of zinc (Zn) in three organic sources (oZn) with different chelation strengths compared to inorganic ZnSO4 (iZn) for broilers fed a low or high phytate diet. A total of 1080, one-d-old male broiler chicks were randomly assigned to one of 18 dietary treatments (six replicates cages of ten chicks per cage) in a completely randomized design involving a 2 × 2 × 4 factorial arrangement with two levels of added phytate (0 or 10 g phytate as sodium phytate/kg), two levels of added Zn (30 or 60 mg/kg) and four Zn sources (iZn and three oZn sources) plus one low and one high phytate control treatments without Zn addition. The three oZn sources consisted of (1) Zn amino acid with weak chelation strength (ZnAA-L, formation quotient Qf = 6.6, containing 119 g Zn/kg), (2) Zn proteinate with moderate chelation strength (ZnPRO-M, Qf = 30.7, containing 133 g Zn/kg) or (3) Zn proteinate with strong chelation strength (ZnPRO-H, Qf = 944.0, containing 186 g Zn/kg). Chicks were harvested at 6 days of age and pancreas metallothionein (MT) mRNA expression was used to estimate Zn RBV. Pancreas MT mRNA expression increased (P<0.01) as dietary Zn level increased. Chicks fed high phytate diets had lower (P<0.05) MT mRNA expression than chicks fed low phytate diets. Based on multiple linear regression slope ratios with ZnSO4 set at 1.00, the RBV of ZnAA-L, ZnPRO-M and ZnPRO-H were 1.01, 1.28 and 0.70, respectively, for low phytate diets, and 1.05, 1.39 and 0.92, respectively, for high phytate diets. The slope for the oZn source with moderate chelation strength differed (P<0.05) from iZn and the other two oZn sources. The RBV of ZnAA-L, ZnPRO-M and ZnPRO-H under the high phytate diet increased by 0.04, 0.11 and 0.22, respectively, compared to those under the low phytate diet. Results indicate that the oZn sources with moderate or strong chelation strength offer partial or complete resistance to interference from high dietary phytate during digestion; and the oZn with moderate chelation strength had a greater RBV with both low and high phytate diets than iZn or oZn sources with weak or strong chelation strength.  相似文献   
998.
Bioassay-directed fractionation of the leaf and root extracts of the antiproliferative Madagascar plant Stuhlmannia moavi afforded 6-acetyl-5,8-dihydroxy-2-methoxy-7-methyl-1,4-naphthoquinone (stuhlmoavin, 1) as the most active compound, with an IC50 value of 8.1 μM against the A2780 human ovarian cancer cell line, as well as the known homoisoflavonoid bonducellin (2) and the stilbenoids 3,4,5′-trihydroxy-3′-methoxy-trans-stilbene (3), piceatannol (4), resveratrol (5), rhapontigenin (6), and isorhapontigenin (7). The structure elucidation of all compounds was based on NMR and mass spectroscopic data, and the structure of 1 was confirmed by a single crystal X-ray analysis. Compounds 2?5 showed weak A2780 activities, with IC50 values of 10.6, 54.0, 41.0, and 74.0 μM, respectively. Compounds 1?3 also showed weak antimalarial activity against Plasmodium falciparum with IC50 values of 23, 26, and 27 μM, respectively.  相似文献   
999.
1000.
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