Change of memory function and decrease of nitric oxide level of whole brain in the transgenic mice expressing human tau 40 with P301L mutation / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To study the mechanism of learning and memory dysfuction in the transgenic mouse expressing human tau 40 isoform with P301L mutation (F10).</p><p><b>METHODS</b>The human tau protein expression and phosphor-tau protein levels were detected with Western blot method. The neurofibrillary tangles were observed with Bielshowsky silver stain. The behavior changes of learning and memory were observed by open field test and passive avoidance test. Acetyleholine level, activities of acetycholinesterase and choline acetyltransferase of whole brain was detected by colorimetry method. The nitric oxide level of whole brain was detected by nitrate enzyme reduction method.</p><p><b>RESULTS</b>Exogenous human tau gene was expressed and an elevation of phosphor-tau protein level in 7 and 3-month transgenic mice's hippocampus andcerebrocortex was observed. The neurofibrillary tangles were observed in cerebrocortex of 7-month transgenic mice; the 7-month transgenic mice also presented an evident reduction of learning and memory ability and nitric oxide level of the whole brain, but not changes in acetylcholine level, acetycholinesterase activity, choline acetyltransferase activity and expression in whole brain.</p><p><b>CONCLUSION</b>Tau transgenic mice (F10) can still inherit their parents' biologiccal characters, and develop learning and memory dysfunction awnodh san obvious decrease in nitric oxide level of whole brain in the 7-month old mice, suggesting a decrease of nitric oxide level of whole brain would be involved in the mechanism of learning and memory dysfunction in these transgenic mice.</p>

HPLC specific chromatograms of drug pair of schizonepetae herba and saposhnikoviae radix / 中国中药杂志

In this experiment, the HPLC specific chromatogram was adopted, with Agilent Extend-C18 (4.6 mm x 250 mm, 5 microm) as the chromatographic column, and 0.5 per thousand trifluoroacetic acid and acetonitrile as the mobile phase for gradient elution, so as to establish specific chromatograms for drug pair of Schizonepetae Herba and Saposhnikoviae Radix from different producing area, identify 12 common characteristic peaks, and obtain the comparison specific chromatography of drug pair of Schizonepetae Herba and Saposhnikoviae Radix. The method is simple, accurate and highly reproducible, and thus can be used as the basis for the quality control of the drug pair.

Effect of hypobaric hypoxia exposure on memory and tau phosphorylation in brain of mice / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To investigate the effect of hypobaric hypoxia (HH)on the cognitive function of mice and the phosphorylation of tau protein in mice brain.</p><p><b>METHODS</b>Forty male mice were randomly divided into 4 groups (n = 10): static control (control) group, 8 hours (8 h) group, 7 days(7 d) group and 28 days(28 d) group, which were exposed to simulated HH equivalent to 5 500 m in an animal decompression chamber for 0 hour, 8 hours, 7 days and 28 days, respectively. Cognitive performances were examined by open field and passive avoidance test, tan phosphorylation was assayed by Western blot.</p><p><b>RESULTS</b>In open field test,the group exposed in hypobaric hypoxia for 28 d showed lower mean velocity (P < 0.05), time in central zone (P < 0.05) was longer than control group. In passive avoidance test 28 d group presented worse performance in both latency time and number of mistakes (P < 0.05) compared with control group. Western blot showed that phosphorylated tau was increased significantly following exposure to HH for 7 d in cortex and 28 d in hippocampus (P < 0.05).</p><p><b>CONCLUSION</b>Tau hyperphosphorylation in brain of mice may play a role in chronic HH-induced cognitive function impairment.</p>

The clinical studies of hyperhomocysteinemia and Alzheimer's disease / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To observe the correlation between the decline of cognitive function and the level of plasma homocysteine in patients with Alzheimer's disease (AD).</p><p><b>METHODS</b>Thirty six AD patients were selected from hospitals in Tianjin. The enrolled patients were in accord with the diagnosis criteria. Thirty two control subjects were corresponding patients without AD in the period. Blood samples were extracted from each subject to determine the levels of homocysteine (Hcy) and folate. Cognitive status was evaluated by the mini- mental state examination (MMSE) and clinical dementia rating scale (CDR).</p><p><b>RESULTS</b>The mean value of serum Hcy concentration [(17.51 +/- 5.62) micromol/L] of AD group was higher than that of control group [(12.38 +/- 4.25)micromol/L]. The serum [(5.17 +/- 1.76) microg/L] and diet folate [(206.94 +/- 44.51) microg/d] concentration of AD group were lower than those of control group [(7.92 +/- 2.22) microg/L, (259.74 +/- 41.92) microg/ d]. The incidence of hyperhomocysteinemia in AD group (64%) was higher than that in control group (22%). A significant relation between Hcy concentrations and the CDR was observed. With the increase of Hcy concentrations the CDR raised, and with the increase of Hcy concentrations the MMSE decreased.</p><p><b>CONCLUSION</b>Hyperhomocysteinemia is one of the risk factors inducing the onset of AD. There is a significant negative correlation between Hcy levels and cognitive levels in AD group. Folate deficiency is an important reason to cause elevated Hcy levels in AD.</p>

Relationship between BRCA1 mRNA expression in tumor cells from malignant effusions and chemosensitivity to cisplatin in patients with metastatic malignant effusions / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To explore the mRNA expression of breast cancer susceptibility gene 1 (BRCA1) in tumor cells isolated from malignant pleural and peritoneal effusions, and the predictive role of BRCA1 related to the efficacy of cisplatin-based chemotherapy.</p><p><b>METHODS</b>Tumor cells were isolated from malignant pleural and peritoneal effusions of 31 cancer patients. The response of these tumor cells to cisplatin was determined by CCK8 assay. Real time quantitative RT-PCR was used to examine the BRCA1 mRNA level in the primary culture cancer cells.</p><p><b>RESULTS</b>The expression level of BRCA1 mRNA was 0.618 (0.014 - 18.063) in primary culture tumor cells. The IC(50) of DDP was 2.809 µg/ml in the primary culture tumor cells (0.118 - 19.439 µg/ml). Both BRCA1 mRNA expression and the tumor cells IC(50) of DDP were not significantly related with patient age, gender, the type of primary tumor, whether to accept the chemotherapy and effusion type (P > 0.05). The level of BRCA1 mRNA was negatively correlated with the chemosensitivity in terms of IC(50) of cisplatin (P < 0.001).</p><p><b>CONCLUSION</b>Assessment of expression level of BRCA1 mRNA may be useful in predicting the efficacy of cisplatin-based chemotherapy in patients with metastatic malignant effusions.</p>

Anti-angiogenic effect of vinorelbine in combination with cetuximab in vitro and in vivo / 中华肿瘤杂志

<p><b>OBJECTIVE</b>This experiment aims to study the anti-angiogenic ability of vinorelbine combined with cetuximab in vitro and in vivo.</p><p><b>METHODS</b>Human lung adenocarcinoma A549 cells were used as control group. Proliferation of human umbilical vein endothelial cells (HUVEC) was assessed by MTT assay. Furthermore, we used Transwell chambers, capillary tube formation and flow cytometry to observe the effects of vinorelbine combined with cetuximab on HUVEC migration, tube formation and cell apoptosis, respectively. In addition, the anti-angiogenic ability of the drugs was checked using chicken chorioallantoic membrane (CAM) model.</p><p><b>RESULTS</b>The inhibitory rate of HUVEC growth was 25.8%, 39.2%, 54.0% for vinorelbine at the concentration of 0.1 ng/ml, 0.4 ng/ml, and 0.8 ng/ml, respectively; that of 0.25 microg/ml cetuximab was 19.7%, and that of 0.1 ng/ml vinorelbine + 0.25 microg/ml cetuximab, 0.4 ng/ml vinorelbine + 0.25 microg/ml cetuximab and 0.8 ng/ml vinorelbine + 0.25 microg/ml cetuximab was 29.5%, 46.4%, 64.6%, respectively. The inhibitory rates of the drugs at the above mentioned combinations of migration and tube formation of HUVEC were 51.9%, 68.2%, 95.0%, respectively. The inhibitory rate of 0.1 ng/ml + 0.25 microg/ml cetuximab and 0.4 ng/ml vinorelbine + 0.25 microg/ml cetuximab on tube formation of HUVEC was 38.8% and 57.7%, respectively, showing a sub-additive effect, and that of combination of 0.8 ng/ml vinorelbine + 0.25 microg/ml cetuximab was 78.9%, showing a synergistic effect. In addition, the apoptotic rate of HUVEC induced by 0.8 ng/ml vinorelbine + 0.25 microg/ml cetuximab was 59.9%, showing a synergistic effect. The in vivo experiment also showed that the combination of the two drugs had a synergistic anti-angiogenic effect.</p><p><b>CONCLUSION</b>Both low dose vinorelbine and cetuximab have an anti-angiogenic effect in vitro and in vivo, and the combination of the two drugs has sub-additive or synergistic inhibitory effect on angiogenesis.</p>

Differential gene expression of the inhibitor of apoptosis proteins in docetaxel-resistant gastric cancer cells / 中华肿瘤杂志

<p><b>OBJECTIVE</b>Resistance to chemotherapy may indicate an unfavorable outcome for patients with gastric cancer. The purpose of this study was to examine whether docetaxel-resistance could be due in part to the expression of the inhibitor of apoptosis proteins (IAP).</p><p><b>METHODS</b>Docetaxel-resistant cells, BGC-823/R1, BGC-823/R2 and BGC-823/R3, were established from parent BGC-823 cells by stepwise increasing concentration of docetaxel. To characterize these cells, we examined the effects of docetaxel on cell growth and apoptosis by MTT assay and double staining with both annexin-V-FITC and PI, and analyzed the cross-resistance to various anticancer drugs. Expression of IAP compared with that in parental cells was evaluated by real-time quantitative PCR.</p><p><b>RESULTS</b>The BGC-823 resistant cells, BGC-823/R1, R2 and R3 cells, were 10.2-, 24.5-, 56.3-fold more resistant to docetaxel than parental cells, respectively, and this resistance was paralleled with reduced induction of apoptosis. BGC-823/R3 cells showed cross-resistance to paclitaxel, whereas exhibited weak or no cross-resistance against 5-fluorouracil, cisplatin and oxaliplatin. The expressions of survivin and XIAP were gradually increased with the extent of docetaxel resistance (r = 0.909, P < 0.001 and r = 0.892, P < 0.001, respectively).</p><p><b>CONCLUSION</b>IAP may make an important contribution to the resistance to the apoptotic effect of docetaxel in gastric cancer, and could be used as a potential therapeutic target.</p>

Inhibitory effect of oxaliplatin in combination with hyperthermia on angiogenesis / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To study the effect of oxaliplatin in combination with hyperthermia on angiogenesis in vitro and in vivo.</p><p><b>METHODS</b>MTT method was used to observe the influence of oxaliplatin on the proliferation of human umbilical vein endothelial cells (HUVEC) or human colon cancer cells (LOVO). The influence of oxaliplatin on HUVEC migration was evaluated by Transwell. Chick embryo chorioallantoic membrane (CAM) model was used to check whether the neovascularization of CAM could be suppressed in vivo.</p><p><b>RESULTS</b>The survival rate of HUVEC was 80.1% - 42.5% within a range of 0.5 - 16 microg/ml and was negatively correlated with the concentration (correlation coefficient was - 0. 943, P = 0.005). The survival rate of LOVO cells within those doses was more than that of HUVEC. There was a synergistic antiangiogenic effect when a combination of oxaliplatin (0.5 microg/ml, 1 microg/ml and 16 microg/ml) with hyperthermia was used while additional effect was shown by the combinatioin of oxaliplatin (2 microg/ml, 4 microg/ml and 8 microg/ml) and hyperthermia in vitro. Oxaliplatin inhibited migration of HUVEC in vitro at low doses (0.25 - 2 microg/ml), and also suppressed angiogenesis of CAM in vivo at doses of 1 -4 microg/ml.</p><p><b>CONCLUSION</b>The results of this experiment showed that low dose of oxaliplatin has anti-angiogenic effect in vitro, while in combination with hyperthermia has additional effect both in vivo and in vitro.</p>

Diagnosis of Alport Syndrome by Immunohistochemical Staining of Type Ⅳ Collagen ? Chains on Paraffin-Embedded Renal Sections / 实用儿科临床杂志

Objective To investigate the diagnostic technique of Alport syndrome(AS)by immunohistochemical staining of type Ⅳ collagen ? chains on paraffin-embedded renal sections.Methods Renal biopsies were obtained from 2 patients with autosomal recessive form of AS,2 female patients and 2 male patients with X-linked dominant form of AS and 2 patients with hematuria(1male and 1 female).AS was diagnosed according to symptoms,family history,pathology,immunofluorescence staining of type Ⅳ collagen ? chains on renal and skin biopsies and gene analysis.Normal portions of nephrectomized kidneys from 2 patients with renal tumor were used as controls.Type Ⅳ collagen ? chains were stained by two-step immunohistochemistry staining method on paraffin-embedded renal sections.Three antigen retrieval methods including autoclave heating,pepsin digestion and proteinase were investigated to find the best antigen retrieval method for type Ⅳ collagen ? chains.The findings were compared with those examined by immunofluorescence staining on fresh frozen sections.Results By immunohistochemistry staining,type Ⅳ collagen ?3 and ?5 chains showed continuous linear pattern along glomerular basement membrane on sections from the controls and the hematuria patients,intermittent linear pattern for X-linked dominant female AS patients,negative for X-linked dominant male AS patient.For patients with autosomal recessive AS,the staining of type Ⅳ collagen ?3 and ?5 chains were negative on glomerular basement membrane,but ?5 chain was positive on glomerular capsules and partial tubular basement membrane.The results were the same as those examined by immunofluorescence staining.Conclusion AS can be diagnosed by immunohistochemistry staining of type Ⅳ collagen on paraffin-embedded renal sections,which is a new technique for diagnosis of AS in China.