神经生长因子对小鼠突触体内Ca^2＋水平的调节作用

观察了多次海马内微注射ＮＧＦ对小鼠突触体内游离钙水平的影响，并在离体情况下观察ＮＧＦ对ＥＧＴＡ和ＣａＣｌ２分别造成突触体内低钙和高钙状态的调节作用。结果如下：（１）在体实验表明，一定剂量的ＮＧＦ可显著降低老年小鼠海马突触体内游离钙水平（Ｐ＜００５）；（２）离体实验表明，当突触体游离钙水平降低时，适当剂量的ＮＧＦ具有升高游离钙水平的作用；而突触体内游离钙水平升高时，则ＮＧＦ有降低游离钙水平的作用。提示ＮＧＦ对游离钙水平的双向调节作用可能是ＮＧＦ改善老年性记忆衰退的作用机制。     

Genetic polymorphisms in dopamine-related genes and smoking cessation in women: a prospective cohort study

Background  

Genes involved in dopaminergic neurotransmission have been suggested as candidates for involvement in smoking behavior. We hypothesized that alleles associated with reduced dopaminergic neurotransmission would be more common in continuing smokers than among women who quit smoking.     

Ultrasonography in the detection of Achilles tendon xanthomata in heterozygous familial hypercholesterolemia.

We have examined the usefulness of ultrasound (US) in the detection of Achilles tendon (AT) xanthomata in heterozygous familial hypercholesterolemia. Our study is based on 30 adult subjects with heterozygous familial hypercholesterolemia (FH) (16 men, 14 women), 27 subjects with other non-familial forms of severe hypercholesterolemia (non-FH) with serum total cholesterol levels > or = 8 mmol/l (13 men and 14 women) and 31 subjects without marked hypercholesterolemia of the same age (control group; serum total cholesterol < 8 mmol/l) (15 men, 16 women). The three groups were comparable with respect to age, sex and body mass index. In the control group the mean sagittal thickness of AT was 4.5 mm (95% CI 3.2, 5.9 mm) and the mean coronal breadth of AT 11.0 (95% CI 9.0, 13.0 mm). Mean thickness of AT was 4.9 (range 4-7) mm in the non-FH group and 11.1 (5-16) mm in the FH group. The mean breadth of AT was in these groups 12.0 (10-17) mm and 19.2 (12-27) mm, respectively. Using the upper 95% confidence interval cut-off point in the control group as a criterion for normal AT thickness and breadth, 6 (22%) of non-FH and 29 (97%) of FH patients had increased AT thickness and 5 (19%) vs. 26 (87%) patients had increased AT breadth, respectively. The sensitivity of AT thickness for identifying FH was 0.97, specificity 0.78 and positive predictive value 0.83. The sensitivity of AT breadth in identifying FH was 0.87, specificity 0.81 and positive predictive value 0.84. None of the control subjects and none of the non-FH patients showed structural abnormalities of AT in the US, whereas 89% of FH-patients showed hypoechogenicity of AT. FH-score obtained by summing up the number of abnormal US findings gave a sensitivity of 0.93, a specificity of 0.96 and a positive predictive value of 0.96 for AT US in discriminating FH from non-FH. In conclusion, US examination of AT is a useful method in the detection of AT xanthomata and thus of help in the diagnosis of heterozygous FH.     

Survival after gastric adenocarcinoma resection: Eighteen-year experience at a single institution

Gastric adenocarcinoma is the second leading cause of cancer death worldwide. In Western series, survival rates vary widely and are generally lower than those reported from Eastern series. We performed a retrospective analysis of cases operated on at the Johns Hopkins Hospital over the past 18 years and collected data on demographics, tumor characteristics, pathologic stage, treatment methods, complications, survival time, and other relevant factors. Survival according to stage of disease, Lauren tumor type, tumorlocation,time period, andadministration of adjuvant therapy wasanalyzed, andresultswerecompared with those of other Western series. During this period, 436 patients with gastric adenocarcinoma underwent resection. We have shown a statistically significant association between survival and margin status, stage of disease, and Lauren tumor type. Overall 5-year survival was 26%, and 5-year survival after R0 resection was 33%. No significant difference was detected between survival and tumor location, time period of treatment, or administration of adjuvant therapy. Analysis of various Western series reveals major differences between the cohorts under study, such as stage of disease, extent of resection, tumor type, and tumor location. Many of the reported differences among Western series may be due to cohort differences, such as stage of disease, extent of resection, tumor type, and tumor location.     

Herpetic croup: two case reports and a review of the literature

Croup is an acute infectious illness usually occurring in children; it is characterized by brassy cough and stridor. The main pathogens include mainly parainfluenza and influenza viruses. Recently there have been reports of prolonged croup caused by the herpes simplex viruses. We report two cases of prolonged croup due to herpes simplex types 1 and 2. We also review and summarize the reported pediatric cases of herpetic croup.     

Induced luteolysis in the primate: rapid loss of luteinizing hormone receptors

The molecular mechanisms involved in luteolysis are still unclear in the primate. This study aimed to investigate the effect of induced luteolysis on the ovarian luteinizing hormone (LH) receptor and the steroidogenic enzyme, 3beta-hydroxysteroid dehydrogenase (3beta-HSD) in the marmoset monkey. Luteolysis was induced in the mid-luteal phase either directly by systemic prostaglandin F2alpha (PGF2alpha), or indirectly by LH withdrawal using systemic gonadotrophin releasing hormone antagonist (GnRHant) treatment. The LH receptor was studied by isotopic mRNA in-situ hybridization and in-situ ligand binding and 3beta-HSD expression was studied using isotopic mRNA in-situ hybridization and immunohistochemistry. Induced luteolysis was associated with a reduction in the expression of LH receptor (P < 0.0001) and 3beta-HSD mRNA, closely followed by a reduction in the LH receptor (P < 0.05) and 3beta-HSD protein concentrations within 24 h. There were no differences in the findings whether luteolysis was induced with PGF2alpha or GnRHant. This study shows that disparate mechanisms to induce luteolysis in the primate result in an identical rapid loss of the LH receptor and 3beta-HSD. In conclusion, induced luteolysis leads to rapid loss of the steroidogenic pathway in luteal cells.