Oral Probiotics Improves Aluminum-induced Hippocampal Inflammation in Mice / 中山大学学报(医学科学版)

@#【Objective】To investigate whether oral administration of probiotics could improve the aluminum-induced hippocampal inflammation in mice.【Methods】Twenty-four 8-week-old male C57BL/6 mice were randomly divided into 4 groups，6 in each. The mice in control（CON）group，AlCl3-treated（Al）group，probiotics-treated（PO）group and treatment-combined（Al+PO）group were treated with sterile water，oral AlCl3，probiotics in sterile water and a combination of oral AlCl3 and probiotics in sterile water ，respectively. After six weeks of treatment，immunofluorescence staining was used to test the numbers of activated microglia（Iba-1+/CD68+ cells） and the expression level of brain-derived neurotrophic factor（BDNF）in hippocampus；enzyme linked immunosorbent assay（ELISA）was employed to determine the levels of interleukin- 1 β（IL- 1 β） and tumor necrosis factor- α（TNF- α）in serum and hippocampus.【Results】 The morphology revealed that compared with those in CON group，in Al group，the numbers of Iba-1+/CD68+ cells increased significantly（P < 0.01）and the BDNF level decreased significantly（P < 0.01）. Compared those in Al group ， in Al+PO group ，the numbers of Iba-1+/CD68+ cells were significantly lower（P < 0.01）and the BDNF level significantly higher（P < 0.01）. ELISA results showed that compared with those in CON group，in Al group，the levels of IL-1β and TNF- α in serum and hippocampus had a significant rise（P < 0.01）. Compared those in Al group，in Al+PO group，the levels of IL- 1 β in serum and hippocampus and TNF-α in hippocampus had a significant reduction （P < 0.01）.【Conclusions】Oral probiotics improves the aluminum-induced hippocampal inflammation in mice.

Molecular mechanisms of Arg77Cys missense mutation and Arg174stop nonsense mutation of factor XIII A gene causing severe factor XIII deficiency / 中国实验血液学杂志

The present study was aimed to investigate the molecular mechanisms responsible for the pathogenesis of severe factor XIII (FXIII) deficiency. Site-directed mutagenesis was conducted to obtain human FXIIIA expression plasmids bearing the mutations. Wild type FXIIIA recombinant plasmid (pcDNA3.1-FXIIIA-wt) and 2 mutant FXIIIA recombinant plasmids (pcDNA3.1/FXIIIA/77mut, pcDNA3.1/FXIIIA/174mut) were transfected into the cultured COS-7 cells using lipofectamine 2000 transfection reagent, respectively. FXIII activities were measured by the Berichrom(®) FXIII chromogenic assay. The expression levels of FXIIIA mRNA were detected by real-time RT-PCR. The recombinant FXIIIA mutants were determined by using Western blot and ELISA. The results showed that the normalized mRNA levels of 2 mutants in transfected COS-7 cells were 0.82 ± 0.21 and 0.76 ± 0.17, respectively. The relative levels of both mRNA transcripts were not significantly decreased as compared with the wild type (1.06 ± 0.51). FXIII activity and FXIIIA antigen levels in concentrated media of cell expressing the wild type protein were (24.0 ± 2.9)% and (13.2 ± 2.3)%, respectively. FXIII activity and FXIIIA antigen levels in cell lysates containing the wild type recombinant protein were (61.6 ± 30.4)% and (32.8 ± 14.5)%, respectively. However, the antigen levels and activity of 2 mutants were severely decreased as compared to the wild type. It is concluded that both mutations severely disturb the normal expression of FXIIIA protein. The reduction of expression levels and decreased activities of the 2 mutants provides a convincible explanation for the deficiency phenotype in the index case.

Effect of temperature on the activation of myocardial KATP channel in guinea pig ventricular myocytes: a pilot study by whole cell patch clamp recording / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The myocardial ATP sensitive potassium channel (K(ATP) channel) has been known for more than two decades, the properties of this channel have been intensively investigated, especially the myocardial protection effect by opening this channel. Numerous studies, including hypothermic, using K(ATP) agonists to achieve a hyperpolarizing cardioplegic arrest, have shown a better myocardial protection than potassium arrest. However, there is no evidence showing that K(ATP) channel could be opened by its agonists under profound hypothermia. We investigated the effect of temperature on activation of myocardial K(ATP) channel by nicorandil.</p><p><b>METHODS</b>Isolated ventricular myocytes were obtained by collagenase digestion of the hearts of guinea pigs and stored in KB solution at 4 degrees C. With a steady ground current, the myocytes were perfused with 1 mmol/L nicorandil until a steady IK(ATP) occurred. Then the cells were perfused with 1 mmol/L nicorandil plus 1 micromol/L glybenclamide. Currents signals were recorded on whole cells using patch clamp technique at several temperatures. The temperature of the bath solution around myocytes was monitored and was controlled at 4 degrees C, 10 degrees C, 20 degrees C, 25 degrees C and 35 degrees C respectively. About 10 cells were tested at each temperature, the cells were considered useful only when the outward current could be induced by nicorandil and blocked by glybenclamide. All data were analyzed using Graphpad PRISM 3.0 (Graphpad, San Diego, CA, USA). Nonlinear curve fitting was done in Clampfit (Axon) or Sigmaplot (SPSS).</p><p><b>RESULTS</b>At 4 degrees C, 10 degrees C, 20 degrees C, 25 degrees C and 35 degrees C, the time needed to open the myocardial K(ATP) channel was (81.0 +/- 0) minutes, (50.5 +/- 11.7) minutes, (28.8 +/- 2.3) minutes, (9.4 +/- 10.2) minutes and (2.3 +/- 1.0) minutes respectively (P = 0.003). The linear relationship between temperature and time needed to open the channel was y (min) = (4348.790 - 124.277x)/60, where y (min) is time needed to open K(ATP) channel, x is temperature, correlation coefficient r = -0.942 (P = 0.00), regression coefficient b = -124.277 (P = 0.00). The current densities among different temperatures were statistically different (P = 0.022), the current density was greater after the activation of K(ATP) channel at higher temperatures. The lower the temperature, the fewer cells in which K(ATP) channels could be opened. At 4 degrees C, only one cell in which the K(ATP) channel could be opened, took a quite long time (81 minutes) and the I-V curve was quite untypical.</p><p><b>CONCLUSIONS</b>K(ATP) channel activated by nicorandil is temperature dependent and the temperature linearly related to time needed to open K(ATP) channel; the lower the temperature, the longer the time needed to open channel and the smaller the current density. At profound hypothermia, it is difficult to activate K(ATP) channels.</p>

Specific humoral immune responses in rhesus monkeys vaccinated with the Alzheimer's disease-associated beta-amyloid 1-15 peptide vaccine / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Alzheimer's disease (AD) is a neurodegenerative disorder characterized by overproduction of beta-amyloid (Abeta), with the subsequent pathologic deposition of Abeta which is important for memory and cognition. Recent studies showed murine models of AD and AD patients inoculated with Abeta(1-42) peptide vaccine had a halted or delayed pathological progression of AD. Unfortunately, the clinical phase IIa trial of Abeta(1-42) peptide vaccine (AN1792) was halted prematurely because of episodes of menigoencephalitis in 18 of the vaccinated patients. The vaccination of BALB/c or Tg2576 transgenic mouse with Abeta(1-15) peptide vaccine is safe and the immune effects are satisfactory. This study further characterizes the specific humoral immune responses in adult rhesus monkeys induced by Abeta(1-15) peptide vaccine.</p><p><b>METHODS</b>Five male adult rhesus monkeys were injected intramuscularly with Abeta(1-15) peptide vaccine at baseline and at weeks 2, 6, 10, 14, 18 and 22. The titers and IgG isotypes of the antibody against Abeta(1-42) in serum was measured by Enzyme-linked Immunosorbent Assay (ELISA). The specificity of the antibody against Abeta(1-42) was determined by Western blot. The Abeta plaques in Tg2576 transgenic mouse brain were stained with the antiserum using immunohistochemistry method.</p><p><b>RESULTS</b>At the eighth week after the vaccination, antibody against Abeta(1-42) began to develop significantly in serum. The titers of the antibody increased following vaccine boosted and reached 1:3840 at the twenty-fourth week, then decreased after the termination of inoculation. The IgG1 was accounted for the highest level in the antiserum pool. The antibody against Abeta(1-42) showed high specificity. The Abeta plaques in Tg2576 transgenic mouse brain were labeled with the antiserum.</p><p><b>CONCLUSION</b>Abeta(1-15) vaccine can induce vigorously specific humoral immune responses in adult rhesus monkey.</p>