Application of case teaching method on clinical medical student in regional anatomy study / 中华医学教育探索杂志

Objective To explore the effect on traditional experiment and case teaching method in regional anatomy study. Methods 80 students from 2014 medical students were randomly selected as the teaching subjects and divided into traditional group and case teaching group. The traditional group con-tained 40 students, using the traditional teaching method, while case teaching group had also 40 students with case teaching method. In the process of teaching, three clinical cases were introduced, including thesubtotal thyroidectomy thoracic outlet syndrome andpancreatic cancer. After the end of the course, the students conducted a unified questionnaire and examination. SPSS 18.0 was used for data line t test or chi square test between the two groups. Results The scores of the students in the case group in the selection questions, blanks and essay questions in the final exam were higher than those of the traditional group; The average total score of the case group was (85.69 ±11.61), while the traditional group was (73.19 ±18.66), and the difference was statistically significant (t=3.597, P=0.002). The results of the questionnaire showed that the students in the case group were higher than the traditional group, and the difference was statistically significant ( χ2=14.753, P=0.001). Conclusion The effect on regional anatomy study with case teaching method is better than the traditional teaching method, and it is a promising teaching reform for the med-ical students.

The optimized culture and identification of astrocytes from rat cortical tissue / 西安交通大学学报(医学版)

Objective To obtain highly purified astrocytes and identify the cells in each stage to support further studies.Methods The cerebral cortex of a neonatal SD rat was isolated and prepared into single cell suspension.The obtained cells were purified by differential adherence and shook at a constant temperature.By inverted phase contrast microscopy and HE staining,cell morphology was observed.The immunofluorescence staining with anti-mouse GFAP was used to identify the cells.Results The primary cortical cells developed rapidly at 3 d after culture and covered the flasks at 9-12 d.At this time,the cells showed stratification and the astrocytes lay at the lower layer.GFAP positive rate was only about (67.2 ±7.1)%.After the first passage,GFAP positive rate increased obviously (84.0±6.0)%. However, oligodendrocytes and microglias could not be removed completely,and the cells also showed stratification.Through 3 times of passages,we obtained many single species of astrocytes showing satellite shape with 2 or 3 processes,big cell body and round or oval-shaped nuclei leaned to one side.Immunofluorescence staining showed that nearly all of the cells were strong positive and the positive rate reached as high as (97.6 ± 2.4 )%.Conclusion Through differential adherence and shaking at a constant temperature,more astrocytes of high purity and in good state can be obtained.

Prokaryotic expression and immunogenicity of the chimeric HBcAg containing Aβ(1-15) / 中南大学学报(医学版)

OBJECTIVE@#To construct a recombinant prokaryoticexpression plasmid pET/ c-Aβ(15)-c, and evaluate the immunogenicity of its encoded fusion protein as expressed in E.coli.@*METHODS@#The gene fragment HBc88-144 was amplified by PCR and subcloned to pUC19. The synthetic, double-strand Aβ(1-15) gene was inserted downstream of HBc1-71 in pGEMEX/c1-71. After restriction enzyme digestion, c1-71- Aβ(15) was spliced to HBc88-144, yielding the recombinant gene c-Aβ(15)-c; that gene was subcloned into pET-28a(+). The fusion protein (CA15C) expressed in the transformed E.coli BL21 was induced with isopropyl β-D-1-thiogalactopyranoside (IPTG) and analyzed by SDS-PAGE. The virus-like particle (VLP) formed by fusion protein CA15C was observed with transmission electric microscope (TEM). Four Kunming (KM) mice were given intraperitoneal injections of CA15C, and the anti-Aβ antibody elicited was detected by indirect ELISA.@*RESULTS@#The sequence of the recombinant gene was confirmed by restriction enzyme digestion and DNA sequencing. After IPTG induction, the fusion protein was expressed, mainly in the sediment from the bacterial lysate. The expression level was 40% of total protein in the sediment. The CA15C could form VLP. After 5 rounds of immunization, the titer of anti-Aβ antibody in the sera of KM mice reached 1:10000, while the anti-HBc antibody was undetectable.@*CONCLUSION@#Recombinant c-Aβ(15)-c gene can be expressed in E.coli. The expressed protein can form VLPs and has a strong immunogenicity.

Effect of tanshinone IIA on the change of calcium current induced by beta-amyloid protein 25-35 in neurons of nucleus basalis of Meynert / 中南大学学报(医学版)

OBJECTIVE@#To explore the effect of tanshinone IIA (TanIIA) on calcium current induced by beta-amyloid protein 25-35 (Abeta25-35) in neurons of nucleus basalis of Meynert (nbM).@*METHODS@#Cell acute dissociated technique and the whole-cell recording model of patch-clamp technique of single-cell were used. The voltage-dependent calcium current in neurons of nbM was recorded in SD rats first. Then the effect of TanIIA on the voltage-dependent calcium current in the neurons was assayed. The change of calcium current induced by Abeta25-35 as well as the effect of TanIIA on the change of calcium current induced by Abeta25-35 in neurons of nbM were analyzed.@*RESULTS@#Extracellular fluid containing different concentrations of TanIIA was irrigated, respectively. The peak current did not change obviously. There was no difference in current density between the TanIIA group and the control group at 0 mV (P>0.05). Extracellular fluid containing 200 nmol/L Abeta25-35 was irrigated after the normal calcium current recorded under whole patch clamp, and the peak current changed obviously. There was distinct difference in the current density between the Abeta group and the control group at 0 mV (P0.05).@*CONCLUSION@#In vitro, TanIIA could inhibit the calcium current amplification induced by Abeta25-35 in neurons of nbM. TanIIA may protect neurons against the toxicity of Abeta and decrease the inward flow of Ca(2+).

The β-amyloid protein induces S100β expression in rat hippocampus through a mechanism that involves IL-1 / 药物分析学报

Objective To explore the effect of β-amyloid protein (Aβ) on S100β expression in rat hippocampus and its mechanisms. Methods At 7 days after bilateral stereotaxis injection of different dose of fibrillar Aβ 25-35 and interluekin-1 receptor antagonist (IL-1ra) into the rat CA1 region, the learning and memory abilities of rats were tested with passive avoidance task. Amyloid deposition was detected by using Congo red staining technique. Nissl staining and immunohistochemical techniques were used to analyze the number of neurons, and GFAP and the S100β expression in hippocampal CA1 region , respectively. Results After fibrillar Aβ injection, the step-through latency of rats was significantly shortened compared to that of the control group. The GFAP positive astrocytes were found surrounding amyloid deposition. Neuronal loss occurred in the pyramidal cell layer of CA1 region. The number of S100β positive cells in Aβ-treated group was significantly increased compared with that in the control group. After IL-1ra injection, the number of S100β positive cells was significantly decreased. Conclusion Intrahippocampal injection of Aβ 25-35 could cause similar pathologic changes of Alzheimer's disease. Aβ 25-35 was capable of up-regulating S100β expression in a dose-dependent manner. The injection of IL-1ra could attenuate the effect of Aβ on S100β expression.

EFFECT OF THE TOTAL SAPONIN OF DIPSACUS ASPER ON INTRACELLULAR FREE CALCIUM CONCENTRATION IN THE CELLULAR MODEL OF ALZHEIMER'S DISEASE-SCANNING CONFOCAL MICROSCOPY / 药物分析学报

Objective To study the effect of ginsenoside Rb1(Rb1) and total saponin of dipsacus asper(tSDA) on intracellular free calcium concentration([Ca2+]i) mediated by β-amyloid protein(A β).So as to lay a foundation for developing effective Chinese traditional medicine to treat Alzheimer's disease(AD).Methods The technique of laser scanning confocal microscopy combining primary cultured neurons was adopted to quantitatively analyze the change of [Ca2+]i.Results The [Ca2+]i of primary cultured hippocampal neurons was (185.76±56.22)nmol*L-1 on basal levels.Control group showed obvious change of calcium vibration,[Ca2+]i was elevated to (1383.78±62.83)nmol*L-1.The peak of [Ca2+]i of Rb1 group reached (311.95±32.67)nmol*L-1 and was lower than that of control group (P＜0.01).The tSDA group displayed distinct change of calcium vibration too,and [Ca2+]i reached (358.01±35.42)nmol*L-1.There was a significant difference in [Ca2+]i between control and tSDA group (P＜0.01).Conclusion The research indicated that one of mechanisms by which Rb1 and tSDA protected the neurons was to maintain the balance of [Ca2+]i.