ObjectiveTo investigate the effects of hippocampal CA3 dopaminergic system in acquisition and consolidation of Pavlovian fear conditioning,and expression of GluR1 and NR2B in medial prefrontal cortex (mPFC),CA1 and basolateral amygdala (BLA) after fear conditioning training.MethodsBilateral injection 6-OHDA into hippocampal CA3 to lesion dopaminergic fibers 2 weeks before fear conditioning training.The change of GluR1 and NR2B were analyzed by western blot after training.ResultsCompared with the saline group ( (66.44 ± 16.58)％ ),there were significant decreases ( (39.24 ± 12.83)％,(31.15 ±6.51 )％ ) in the consolidation of short- and long- term fear memory (P ＜ 0.05 ) but not the acquisition ( ( 65.58 ± 5.33 ) ％,P ＞ 0.05).The expression of GluR1 protein was significantly increased in BLA (P＜0.01 ) but not the mPFC or hippocampal CA1 (P＞1.05 ),compared with the saline group.In addition,the expression of NR2B protein was significantly increased in the mPFC and decreased in BLA (P＜0.01) but not the hippocampal CA1 (P＞0.05),compared with the saline group.ConclusionDown-regulation of dopaminergic system in hippocampal CA3 may impair the consolidation but not the acquisition of fear memory,and also regulate the expression of GluR1,NR2B protein related to fear memory in other brain regions.

As an important segment in the talents' cultivation of medical English major,practical education assumes a positive role in promoting the students' unity of knowing and doing,upgrading their professional kills and improving comprehensive qualities.Taking English major (medical English direction) of Chongqing medical university as an example,the present study attempts to discuss the forms and contents of the practical education,along with the fruitful achievements,in view of students'interests,community service,horizon expanding as well as job hunting and further study pursuing.In addition,some reflections and measures are presented to further boost the practical education.

Objective To investigate the effect of glutamine in combination with umbilical cord blood mesenchymal stem cells ( MSCs) transplantation on intestinal ischemia-reperfusion injury in rats.Methods Umbilical cord blood mesenchymal stem cells were isolated, and were labeled with CM-DiI fluorescent dye.Eighty Sprague-Dawley rats were randomly divided into normal control group, ischemia reperfusion injury group, glutamine group, MSCs transplantation group and combined group with 15 rats in each group.The control group received saline enema.The injury group was treated with TNBS ( ethanol dilution) enema.The glutamine group at 1 h after TNBS received intravenous injection of 0.45 g/kg glutamine.The rats of MSCs transplantation group had tail vein injection of 1 ×1010/L umbilical cord blood mesenchymal stem cell suspension, and the combined group received intravenous injection of glutamine 0.45 g/kg and 1 ×1010/L umbilical cord blood mesenchymal stem cell suspension.ELISA was used to detect the midgut fatty acid binding protein (iFABP), interleukin 6 (IL-6), and superoxide dismutase (SOD) content in the rat serum.The water content of intestinal tissue was detected at 1 h and 3 h after reperfusion in each group.The expressions of NF-kB, Bcl-2 and caspase-3 mRNA and proteins in the rat intestinal epithelial cells after treated with glutamine in combination with MSCs were detected by RT-PCR and Western blot assays.Results The fluorescent tracer method revealed that the transplanted MSCs cells were distributed in the intestinal mucosal lymphoid tissues and glandular epithelial cells, indicating that MSCs might be involved in the repair process of intestinal ischemia-reperfusion injury.The content of serum IFABP and IL-6 in the injured group was significantly higher than that in the control group, while significantly reduced in the glutamine group, MSCs transplantation group and combined group, with the most obvious in the combined group.The content of SOD in the injury group was significantly lower than that in the control group, and significantly increased than that in the glutamine group, MSCs transplantation group, with the most striking in the combined group ( P<0.05 for all) .The water content of intestinal tissue in the injury group at 1 and 3 hours after reperfusion was significantly higher than that in the control group, significantly lower in the glutamine group, MSCs transplantation group and the combined group, with the most decreased in the combination group, and there was no significant difference between the glutamine group and MSCs transplantation group (P>0.05).Compared with the control group, the caspase-3 and NF-kB mRNA and protein expressions in the intestinal mucosal epithelial cells of the injury group were significantly increased, and the expressions of Bcl-2 mRNA and protein were significantly reduced ( P <0.05 ) , the expressions of caspase-3 and NF-kB mRNA and protein were significantly reduced in the glutamine group, MSCs transplantation group and combined group.The expressions of Bcl-2 mRNA and protein were significantly increased ( P<0.05) , while no significant difference was shown between the glutamine group and MSCs transplantation group (P>0.05), but there was a significant difference between these two groups and the combined group (P<0.05).Conclusions After treated with glutamine and MSCs transplantation, the degree of intestinal ischemia reperfusion injury is obviously reduced in rats.It may be mediated through inhibiting the expression of caspase-3 and NF-kB and promoting the expression of Bcl-2.

Exosomes are nanosized lipid vesicles released from cells .They are believed to contain proteins, lipids and nucleic acid cargos , and are capable of deliver their cargos to recipient cells , which in turn alter the expression of genes in neighboring cells .An increasing body of evidence indicates that they play a pivotal role in cell-to-cell communication , which is hijacked during various physiological and pathological conditions , such as myocardial damage , angiogenesis , cardiac remodeling and atherogenesis plaque formation .Further research of intercellular communication mediated by exosomes may potentially aid in the possible application of exosomes for biomarker discovery , curative effects , as well as prognosis of cardiovascular diseases , even the use of exosomes as a therapeutic drug delivery system on the basis of the exosome′s ability to target specific cells , and transfer genetic materials.

BACKGROUND:Bone marrow mesenchymal stem cel s can repair intestinal ischemia-reperfusion injuny by interfering inflammatory reactions after intestinal ischemia-reperfusion to protect intestinal barrier functions. In recent years, umbilical cord blood mesenchymal stem cel s are gradual y used as a substitute source of bone marrow mesenchymal stem cel s. OBJECTIVE:To investigate the effects of umbilical cord blood mesenchymal stem cel s on acute intestinal ischemia-reperfusion injury. METHODS:Umbilical cord blood mesenchymal stem cel s were induced, isolated in vitro and tracked by CM-DiI fluorescent labeling. Sixty-three Sprague-Dawley rats were equivalently randomized into three groups:control group received normal saline enema, intestinal ischemia-reperfusion injury group with ethanol diluted trinitro-benzene-sulfonic acid and transplantation group administrated with 1×1010/L umbilical cord blood mesenchymal stem cel suspension via the tail vein at 1 hour after trinitro-benzene-sulfonic acid modeling. At 3 days after transplantation, colon tissues were removed in each group to observe pathological changes of the intestinal tract by hematoxylin-eosin staining. Besides, expression of leptin mRNA in the colon tissues and cyclooxygenase-2 in the mucosa were detected by RT-PCR and immunohistochemistry method, respectively. RESULTS AND CONCLUSION:Transplanted umbilical cord blood mesenchymal stem cel s distributed in the intestinal lymphoid tissue and among glandular epithelial cel s, suggesting that these stem cel s might be involved in the process of intestinal ischemia-reperfusion injury repair. Compared with the control group, intestinal injury in the injury group was significantly aggravated, and most intestinal epithelial cel s shed;and the transplantation group appeared to have significantly reduced intestinal damage and significantly less cel shedding. Expression of leptin mRNA was significantly higher in the injury group than the transplantation group fol owed by the control group, and there were significant differences among the three groups (P<0.05). Additional y, expression of cyclooxygenase-2 in the injury group was significantly higher than that in the control group (P<0.05);compared with the injury group, expression of cyclooxygenase-2 was significantly lower in the transplantation group (P<0.05). To conclude, leptin and cyclooxygenase-2 may be involved in acute intestinal ischemia-reperfusion injury, and umbilical cord blood mesenchymal stem cel transplantation significantly lessens intestinal ischemia-reperfusion injury, which provides an experimental basis for human treating acute intestinal ischemic injury.

Objective To investigate the effects of hypoxic conditions on expressions of hypoxia-inducible factor 1α (HIF-1α) and P-glycoprotein (P-gp),and the relationship between HIF-1α and P-gp.Methods Tumor tissues from 54 cases of patients with colonic neoplasm in Xingtai People's Hospital were selected after operation from June 2013 to June 2015.The expressions of HIF-1α and P-gp in colonic tumor tissues were detected by using immunohistochemistry,and their correlations to clinical and pathologic features were analysed.The expressions of HIF-1α and P-gp in colonic tumor cell lines under normoxia and hypoxia conditions were detected by using cell smear method,and correlation between HIF-1α expression and P-gp expression was analysed.Results Among tumor tissues from 58 cases of patients with colonic neoplasm,the positive rate of HIF-1α expression was 58.62％,and that of P-gp expression was 46.55％.The positive rates of HIF-1α and P-gp expressions of patients on the Dukes stage C+D were significantly higher than those of patients on A+B phase (P＜0.05).Additionally,the positive rates of HIF-1α and P-gp expressions of patients with lymphatic metastasis were significantly higher than those of patients without lymphatic metastasis (P＜0.05).The HIF-1α expression was positively correlated with the P-gp expression (r=0.574,P＜0.01).For the same cell lines,the expression levels of HIF-1α and P-gp under hypoxia condition were significantly higher than those under normoxia condition,there were statistically significant differences (P＜0.01).While,under the same oxygen conditions,no statistically significant difference was found in expression levels of HIF-1 and P-gp among different colonic tumor cell lines (P＞0.05).Conclusion Overexpression and coexpression of HIF-1α and P-gp exist in colon cancer.The expression levels of HIF-1α and P-gp in patients with different Dukes stages and patients with or without lymph node metastasis are significantly different,and positive correlation is observed between the expression of HIF-1α and P-gp.Hypoxia condition can induce an increase in expressions of HIF-1α and P-gp in colonic tumor cells.

Objective To investigate the effect of maternal deprivation (MD) on neurobehavior and PP1Cγgene expression in hippocampus. Methods Male pups were randomly divided into MD group(thirty-five)and control group(twenty-four). From PND 1 to PND 21 ,pups in the MD groups underwent daily maternal deprivation for 3 h ( Postnatal day). Neurobehavior was observed to investigate neurodevelopment, Morris water maze was used to measure spatial learning and memory,and Real-Time quantitative PCR was employed to analyze PP1Cγ gene expression. Results Several significant deficiencies were observed in bodyweight and grasping reflex while a great enhancement in hot-plate test in rat pups suffering from MD( (26.23 ± 2.81 )g vs. (30. 38 ± 3.85 )g;( 19.37 ± 11.89) s vs. (22.39 ± 17.62 ) s; (4.36 ± 1.76 ) s vs. ( 5.26 ± 2.55 ) s; P ＜ 0. 05 ), but deficiencies in neurological reflexes were subtle ( ( 0.83 ±- 0.30 ) s vs. ( 0. 83 ± 0. 34 ) s; ( 3.68 ± 1.63 ) s vs. ( 5.61 ± 3. 01 ) s;( 3.00 ± 0.00 ) vs. ( 3.00 ± 0. 00); P ＞ 0. 05 ). MD had a subtle influence on spatial learning and memory (P ＞0.05). Meanwhile,MD could lead to PP1Cγ expression down-regulation on PND 22 ( (2.19 ±0.62) vs. (3.52 ±0.86), P＜0. 05)which was in line with early neurobehavior results. No difference was found compared with MD group and control group on PND60 ( ( 1.73 ± 0. 78 ) vs. ( 1.33 ± 0. 34); P ＞ 0.05 ). However, there was the up-regulation of PP1Cγexpression on PND 90 ( (2.85 ± 0. 34) vs. ( 1.34 ± 0.93 ); P ＜ 0.05 ). Conclusion MD alters early neurobehavior and hippocampal PP1Cγgene expression in the Wistar rats,but has a subtle effect on learning and memory. At the same time,MD can make PP1Cγexpression in the hippocampus varying with the age.

Objective To evaluate the efficacy and safety of ureteroscopic endo-incision and drainage in the treatment of renal cysts.Methods Thirty cases(19 females and 11 males)of renal cysts(1 1 parapelvie cysts,15 simple cysts.and 4 multiple cysts)were treated with ureteroscopic endo-incision and drainage.The renal cysts were located in renal pelvis,and opened and decompressed by electrotme with ureteroscope.Double J stent was placed afterwards.Urinary and blood biochemistry were tested post-operatively.Results All the operations were successfully completed with no severe complication.The cyst managing time ranged from 15 tO 45 min.Urinary biochemistry(urinary protein and glucose)turned normal 1 2 days after the surgery.Patients were followed up for 3 to 9 months.Renal cysts disappeared in 24 cases,diminished in 4 cases,and recurred in 2 cases.Conclusion Application of ureteroscopic technique in the treatment of renal cyst is safe,effective and minimally invasive.

Objective To investigate the interactional roles corticosterone and stress played during the PTSD-Like memory impairment.Methods First we established the model of PTSD-like memory using three levels of electric shock:0 mA,0.8 mA and 1.4 mA.The freezing time percent of each group were calculated 24 hours later in order to find which group of rats obtained the PTSD-like memory,and generalizing tests was used to verify it.After the model was established,rats received adrenalectomy (ADX) were operated bilaterally in order to investigate the effect of corticosterone and fed with corticosterone in the drinking water 7 days before fear conditioning.These rats were divided into four groups:control group (no corticosterone supplement,0 mA shock),Cort group (corticosterone supplement,0 mA shock),shock group (no corticosterone supplement,1.4 mA shock),Cort-shock group (corticosterone supplement,1.4 mA shock).A two-way factorial analysis of variance was used to determine whether there was a significant interaction between corticosterone and shock.Results The freezing time percent of group 0.8 mA raised compared with the group 0 mA,whereas the freezing time percent of group 1.4 mA showed reversely and the generalizing effects appeared,compared with group 0.8 mA.In two-way factorial analysis design,the freezing time percent of Cort-shock group significantly increased (P＜0.05) compared with other groups,and there was no significant variance among the other groups.Corticosterone (F=6.464,P＜0.05) and stress (F=53.419,P ＜0.01) played parts in the formation of PTSD-like memory impairment,and they interacted with each other (F=11.580,P＜0.05).Conclusion PTSD-like memory impairment can be induced on rats with high (1.4 mA) electrical shock,and they have interactional effect with each other in the process.

Objective To investigate the effect of ketamine on depression-like behaviors at different developmental stages of offspring rat exposed to prenatal restraint stress (PRS).MethodsPregnant SD rats were randomly divided into control group (n=6) and PRS group (n=8).The dams of PRS group received three times(45 minutes/time)restraint stress every day.The anxiety-like and depression-like behaviors of the offsprings of the two groups were tested in the stage of juvenile,adolescence and early adulthood.Then the antidepressant effect of ketamine on prenatal stress rats at different developmental stages was observed.ResultsIn the open-field test,the time in the central area of the offspring rats in PRS group at different developmental stages (juvenile(2.50±0.43)s,adolescence(9.17±1.05)s,early adulthood(8.33±0.92)s) were significantly lower than those of the control group((8.33±1.05)s,(19.17±1.06)s,(18.83±1.30)s,all P<0.05).In the forced swimming test,the immobility time in the offspring rats of PRS group at the different developmental stages (juvenile(192.50±10.82)s,adolescence(182.75±10.12)s,early adulthood(199.88±9.20) s)were significantly higher than those of control group((76.00±19.00)s,(96.30±12.91)s,(108.30±10.98)s,all P<0.05).Ketamine could quickly and strongly reduce the immobility time of the offsprings exposed to PRS in the stage of adolescence and early adulthood (P<0.01),but the effect was weaker in the juvenile offsprings (P<0.05).ConclusionPRS leads to persistent anxiety-like and depression-like behavior in offsprings and ketamine exerts a good antidepressant effect on the offspring rats in the stage of adolescence and early adulthood.