Murine models of infectious exacerbation of respiratory disease / 中国药理学通报

Asthma, chronic obstructive pulmonary disease (COPD), cystic fibrosis(CF) lung disease are common chronic respiratory diseases. There has been evidence that respiratory in-fections with bacteria and viruses underpin the pathogenesis of the respiratory diseases. It is now well-recognized that early life infections may induce more severe asthma by inducing permanent alterations in immunity and lung structure, and even induce ster-oid-resistant severe asthma in adulthood. Respiratory infections will exacerbate the inflammation and remodeling in lung of COPD. P. aeruginosa infection in lung will induce CF. There are no effective therapies preventing or reversing the exacerbation of respiratory diseases. The development and use of mouse mod-els are proved to be valuable in understanding the role of infec-tion in disease pathogenesis. This article reviews the progresses in murine models of infectious exacerbation of respiratory disea-ses, emphasizes on the pathological changes of the three respira-tory diseases found with the application of murine models, and explores the therapeutic method which can be developed and tested by the application of murine models, in order to offer ref-erence for clinical research and treatment.

Exercise training enhances learning and memory abilities and hippocampal neurogenesis / 中华神经医学杂志

Objective To investigate the effects of regular and irregular mandatory treadmill running (TR) on learning and memory abilities,stress response,survival and maturation of newborn neurons in dentate area of C57 mice. Methods Forty-eight male C57BL/6 mice were randomly divided into regular running group (n=16,definite time and quantity), irregular running group (n=16,definite time and different quantities) and sedentary group (n=16).Injection of bromodeoxyuridine (BrdU,50 mg/kg) was given intraperitoneally to mice from the 1st d to the 7th d of exercise,and then,these mice were subjected to a 4-wk TR training course or sedentary exercise.Double irnmunofluorescence labeling was employed to observe the effect of TR on survival and maturation of newborn neurons. Mice were trained on the Morris water maze to test the abilities of learning and memory. Corticosterone (CORT).level in the venous blood was measured with a radioimmunoassay kit. Results As compared with that in mice of the irregular running group and sedentary group,significant decrease of latency was noted in mice of the regular running group on the 1st, 3rd, 4th and 5th d of place navigation test (P＜0.05). As compared with that in mice of the sedentary group, significant decrease of latency was noted in mice of the irregular running group and regular running group on the 2nd d of place navigation test (P＜0.05),while no significant difference of that was noted between mice of the irregular running group and regular running group (P＞0.05).The platform was removed for a 60-s probe test 4 h after the last trial to test the recall ability, and the times of staying in the target zone in each group were regular running group＞irregular running group＞control group, and significant difference was noted between each 2 groups (P＜0.05). The numbers of double immunofluorescence labeled cells in the dentate gyrus were counted as regular running group＞irregular running group＞control group, and significant difference was noted between each 2 groups (P＜0.05). The serum CORT level was measured as regular running group＜irregular running group＜control group, and significant difference was noted between each 2 groups (P＜0.05). Conclusion Mandatory treadmill running could improve the learning and memory abilities,which may be related to the increment of survival and maturation of neural precursor cells,and decreased level of serum CORT; and the effect of regular mandatory treadmill running is better than that of irregular mandatory treadmill running.

Differentiation of adult mouse mesenchymal stem cells into hepatocytes cultured in a conditioned culture medium of injured hepatocytes / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To establish a method through which murine bone marrow mesenchymal stem cells (MSCs) can be induced into hepatocytes in vitro.</p><p><b>METHODS</b>A conditioned medium of injured hepatocytes (with CCl4 in vivo) was used to culture the isolated MSCs. The differentiated cells were identified by morphological observation, reverse transcription polymerase chain reaction (RT-PCR), immunofluorescence assay (for AFP, Albumin, and CK18) and periodic acid schiff reaction (PAS) for glycogen.</p><p><b>RESULTS</b>The differentiated cells showed characteristics of hepatocytes. PT-PCR detected AFP mRNA on day 5 and it increased gradually until day 15, and then decreased; CK18 mRNA was detected on day 10; TAT was detected on day 20. Immunofluorescence assay for AFP, albumin and CK18 showed positive staining reactions on day 20. PAS positive glycogen granules appeared in the cytoplasm of the differentiated cells.</p><p><b>CONCLUSION</b>MSCs of adult mice cultured in a conditioned medium of injured hepatocytes can differentiate into hepatocytes. This method can be used in further studying of the mechanism of transdifferentiation of MSCs into hepatocytes.</p>

Selective determination of dopamine in the presence of high concentration of ascorbic acid with L-cysteine modified glassy carbon electrodes / 南方医科大学学报

<p><b>OBJECTIVE</b>To establish an assay system for determination of dopamine (DA) in the presence of ascorbic acid (AA) with L-cysteine modified glassy carbon electrode.</p><p><b>METHODS</b>L-cysteine was modified onto glassy carbon electrode electrochemically, and with this modified electrode, dopamine was determined by linear sweep stripping voltammetry.</p><p><b>RESULTS</b>L-cysteine polymer-modified electrode had strong catalytic effect towards the electrochemical oxidation of DA. The modified electrode showed good properties in determination of DA with coexisting AA. Under selected conditions, the linearity of DA was in the range of 2.0 x 10(-7) - 1.0 x 10(-4) mol/L with the detection limit of 2.0 x 10(-8) mol/L. The stability, reliability and recovery of this L-cysteine-modified electrode based on electrochemical method were also satisfactory.</p><p><b>CONCLUSION</b>L-cysteine-modified electrode can avoid the interference by AA for determination of DA.</p>