Effect of corticosterone on developing hippocampus: Short‐term and long‐term outcomes

Many documents implicate that corticosterone plays a negative role in brain function, especially in learning and memory. However, less evidence confirms its direct actions on hippocampal development. In the work reported here, pro treatment, minimum corticosterone administration in infant mice, and con treatment, corticosterone deprivation by adrenalectomy, were used to examine the effects imposed by corticosterone on the structure and function of developing hippocampus. Our study shows that adrenalectomy induces decrease of plasma corticosterone levels and results in the impairment of learning performance and the degenerative changes not in CA regions of hippocampus but in dentate gyrus. Noteworthily, this damage effect is severer in 5‐week‐old mice than that in 10‐week‐old mice. In addition, the short‐term effect of minimum corticosterone administration may accelerate the development of dentate gyrus of 10‐day‐old mice. Moreover, minimum corticosterone administration during infancy contributed to the learning performance and the structural integrity of hippocampal CA regions in different developing stages, while this phenomenon was not observed in dentate gyrus. In conclusion, corticosterone is necessary for the development of dentate gyrus, especially in relatively young individuals, and administration with minimum corticosterone in infancy has a long‐term positive influence on the hippocampal structure and function in different developing stages. © 2008 Wiley‐Liss, Inc.     

Architecture of the Blood‐Spleen Barrier in the Soft‐Shelled Turtle,Pelodiseus Sinensis

We investigated the structure of the soft‐shelled turtle, Pelodiseus sinensi, spleen and demonstrated that there were several microanatomical peculiarities by light and transmission electron microscopy. In the spleen, the white pulp of the spleen was composed of two compartments, the periarteriolar lymphatic sheath (PALS) and periellipsoidal lymphatic sheath (PELS). No lymph nodules and marginal zones were found. The spleen‐blood barrier stood in the PELS and the ellipsoid. The high endothelial lining of penicilliform capillary contained small channels. These channels allowed circulating substances or lymphocytes to enter the ellipsoid. The distal portion of the penicilliform capillaries directly opened to pulp cords. The ellipsoid‐associated cell (EAC) was located at the surface of the ellipsoid. Reticular fibers were mainly distributed in ellipsoid and the outer PELS. Both reticular cells and macrophages were distributed in the outer layers of PELS. S‐100 protein positive dendritic cells were mainly distributed in out cells layer of the PELS and all over the PALS. Forty minutes after injection, carbon particles of Indian ink were mainly observed in the ellipsoid. Few carbon particles were observed in the outer PELS and fewer carbon particles in the red pulp. These findings suggested that a blood‐spleen barrier indeed existed in the soft‐turtle, P. sinensi, and it was a complex composed of an ellipsoid (including supporting cells, EAC, and reticular fibers) and the outer compartments of PELS (including dendritic cells, reticular fibers and cells, macrophages). Anat Rec, 2009. © 2009 Wiley‐Liss, Inc.     

Species distribution and antifungal susceptibility of blood Candida isolates at a tertiary hospital in southern Taiwan, 1999–2006

The aim of this study was to evaluate the incidence of candidaemia, consumption of fluconazole and susceptibility of blood Candida isolates at a tertiary hospital. From January 1999 to September 2006, all candidaemic episodes were identified and available strains were evaluated for the susceptibilities of antifungal agents. Annual defined daily doses of antifungal agents were collected. There had been 909 Candida isolates detected from the bloodstream of 843 patients during the study period. Among them, 740 isolates were available for the susceptibilities of antifungal agents. The incidence density of candidaemia was 28 episodes per 10 000 patient‐days. Species distribution of 909 isolates did not vary annually, but varied greatly in the units of the hospital. Candida parapsilosis was the more prominent (30.1%) isolate in the paediatric units, where C. tropicalis and C. glabrata were less common (12.3% and 1.4% respectively). Resistance rates for itraconazole, fluconazole and voriconazole were 6.9%, 3.8% and 3.8% respectively. There were 25 (3.4%) isolates resistant to amphotericin‐B. Although fluconazole usage increased over time (r² = 0.45; P = 0.07), fluconazole resistance did not increase accordingly (P = 0.33). In our institution in which the incidence of candidaemia was high, fluconazole resistance among blood Candida isolates remained rare.     

Triphenyltin induced growth inhibition and antioxidative responses in the green microalga Scenedesmus quadricauda

The toxicity of organotin compounds in the environment is closely related to their uptake by microorganisms and delivery through the food chain. The population at low trophic levels like microalgae plays an important role in this aspect. In this study, the toxic effects of triphenyltin (TPT) on Scenedesmus quadricauda were assessed at the population, cellular and subcellular levels. The alga was exposed to TPT of up to 64 μg l(-1) (nearly lethal concentration), but the algal growth was inhibited significantly when TPT was elevated to 8 μg l(-1). This growth inhibition was correlated to the presence of oxidative stress as evidenced by the accumulation of malondialdehyde (MDA) and confirmed by fluorescent probing of the intracellular reactive oxygen species (ROS) levels. The imbalanced activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) may lead to an accumulation of intracellular H(2)O(2), which can initiate an oxidative damage to cell components and cause growth inhibition and finally cell death. The detachment of plasma membrane from cell wall, the structural change of chloroplasts as well as the increased number and size of starch granules together with electron-dense deposits in chloroplasts were noticed through electron microscopic examination. It was suggested that mitochondria, chloroplasts and protoplasm might be the direct targets of TPT toxicity. This study confirmed that TPT poisoning on phytoplankton can happen at very low concentrations. There existed different defense mechanisms e.g., antioxidant enzyme activation, starch accumulation and possibly metal sequestration in algal species as the means to resist TPT toxicity.     

Antidiabetic effect of oleanolic acid: a promising use of a traditional pharmacological agent

Diabetes mellitus (DM) is a metabolic disorder characterized by chronic hyperglycemia. Although the clear mechanisms of DM and insulin resistance are still to be cleared, it has been well documented that reactive oxygen species (ROS) play a pivotal role in DM and multiple types of insulin resistance. For the past few years, natural substances have been shown to have the potential to treatment DM. Attention has been especially focused on plants rich in triterpenoids, which generally show antioxidant and antiglycation effect. In our previous studies, it was shown that oleanolic acid (OA), a natural triterpenoid and an aglycone of many saponins, is a potent antioxidant acting as not only a free radical-scavenger through direct chemical reactions but also as a biological molecule, which may enhance the antioxidant defenses. The present study aimed to investigate the potential antidiabetic effect of OA. Oleanolic acid showed a significant blood glucose-lowering and weight-losing effect in diabetic animals induced by streptozotocin (STZ). In the insulin resistant model, it was also shown that OA may promote insulin signal transduction and inhibit oxidative stress-induced hepatic insulin resistance and gluconeogenesis, in which process the phosphorylation of ERK and the protective effect on mitochondrial function may be involved. These findings may significantly better the understanding of the pharmacological actions of OA and advance therapeutic approaches to DM.     

Safety of an injection with a mixture of extracts from Herba Artemisiae annuae, Fructus Gardeniae and Flos Lonicerae

Objective This study aimed to evaluate the safety for an injection with a mixture of extracts from Herba Artemisiae annuae, Fructus Gardeniae and Flos Lonicerae and to determine the risk factors that may affect its adverse drug reactions. Methods A drug-oriented prospective observational study was performed. Physicians filled in clinical observation forms with detailed information of the patients including general information, drug information, therapeutic effects and adverse drug events. The adverse drug reaction factors were analyzed by both mono-factor and multiple-factor logistic regression methods. Results From April to July 2007, we collected 12,427 observation forms from 46 hospitals in Jiangsu Province of China. Among the 11,707 observation forms we analyzed, 8,074 patients were children younger than 14 years old (69%). Among 51 reported adverse drug events, 45 cases were adverse drug reactions. The total adverse drug reaction incidence of the injection was 0.38%. While most adverse drug reactions were previously known (e.g., rash, pruritus, vomiting and diarrhea), we observed three new ADR symptoms: shiver, phlebitis and anhelation. All the adverse drug reactions were controlled very well through the follow-up therapy, and none of them was life threatening. The mono-factor analysis showed that adverse drug reactions of the injection were significantly correlated with total medication dose (P = 0.0049) and combination medication (P = 0.0143), especially with antimicrobial drugs (P = 0.0079) and macrolides (P = 0.0017). The multiple factor analysis confirmed these results: medication dosage and combination medication had a crucial impact on adverse drug reactions of the injection; the risk was increased by 24.8% (the estimated value of relative risk was 1.248, 95% confidence interval: 1.054–1.479) and 89% (1.890, 1.001–3.566), respectively. Conclusion The total adverse drug reaction incidence of the injection was 0.38% and lower than we expected. Moreover, we observed three new adverse drug reactions, none of which was severe.

Pediatric liver transplantation in Hong Kong—a domain with scarce deceased donors

Aim

The study aimed to assess the outcome of live-donor liver transplantation for pediatric patients in a region with limited access to deceased donors.

Patients and Methods

From September 1993 to September 2008, 78 pediatric patients aged between 73 days and 17 years (mean, 40 months) received 83 liver transplants. Sixty-two were living-related liver transplantations (LRLTs), and 21 were deceased-donor liver transplantations (DDLTs). The mean follow-up period was 6.5 years. The prospectively collected data of these patients were analyzed retrospectively.

Results

The 1-, 2-, and 5-year survival rates of patients and grafts were 91%, 90%, 88% and 87%, 86%, 83%, respectively. The survival rates of LRLT patients and DDLT patients were 89%, 89%, 87%, and 90%, 86%, 86%, respectively (P = .58). The survival rates of patients aged 12 months or younger and patients older than 12 months were 95%, 92%, 90% and 90%, 90%, 87%, respectively (P = .65). One live donor developed temporary peroneal palsy, and another developed lung collapse (3%, 2/62). All live donors resumed their normal activities with no difficulty.

Conclusion

With meticulous surgical techniques and postoperative care, it is justifiable to accept donated livers from voluntary live donors for transplantation to save pediatric patients in a place with scarce deceased donors.     

Association between Helicobacter pylori concentration and the combining frequency of histopathological findings in gastric biopsies specimens

BACKGROUND: Helicobacter pylori is the most prevalent infectious agent worldwide. About 90% of patients with chronic gastritis are infected with this bacterium. Some studies have shown a association between the H. pylori concentration and the scores of gastritis activity and severity. AIM: To evaluate the association between H. pylori concentration and the combining frequency of findings on histopathological examination. METHODS: Two hundred consecutive gastric endoscopic biopsies diagnosed as chronic gastritis were retrospectively investigated. The Warthin-Starry silver stain was used to study H. pylori and the following parameters were assessed (according to the Sydney system): 1. infiltration by polymorphonuclear cells in chorio and epithelium (activity) graded as mild, moderate and marked; 2. presence of lymphoid follicles; 3. presence of intestinal metaplasia; 4. presence of regenerative cell atypias, graded as mild, moderate and marked; and 5. H. pylori concentration on the mucous covering the foveolar epithelium. RESULTS: The most frequent association was chronic gastritis and activity, regardless of H. pylori concentration. The association of five histopathological findings in the same biopsy has not occurred in the cases of higher concentration of H. pylori. CONCLUSION: Our study has not revealed any association between H. pylori concentration and an increasing in the number of histopathological findings found in the gastric mucosa. Since referring to its presence is much more important than to its concentration.     

中国人共刺激信号抑制配体表达载体的构建及在大肠杆菌DH5α中的表达

构建CTLA－4基因表达载体并在大肠杆菌DH5α中表达CTLA－4蛋白。方法：用PCR方法获得中国人CTLA－4基因第二外显子，构建重组表达质粒pPBCTLA，转化大肠杆菌DH5α，以PCR和RFLP方法筛选阳性克隆，以免疫印迹技术检测表达产物。结果：阳性重组子在DH5α中经温度诱导表达CTLA－4蛋白，分子量与理论值相符（约12kD)，进一步分析表明，CTLA－4蛋白主要以包涵体形式存在。Western-blot结果证实，12k的表达条带可与标准羊抗人CTLA－4ITgG起特异反应。淋巴细胞转化实验结果表明该蛋白具有明显的免疫抑制作用。结论：用基因工程技术获得中国人CTLA－4基因表达蛋白，为进一步研究CTLA－4的生物学功能及研制CTLA－4抗体奠定了基础。     

舌癌与瘤内血管形成相关性研究

目的　研究瘤内血管密度 (MD)与舌癌淋巴结转移、复发以及对预后的影响。方法　采用免疫组化SP法FⅧ因子多克隆抗体对 36例舌癌、瘤内血管进行标记分析。结果　颈淋巴结转移组 (19例 )MD31 35± 4 42 ,明显高于无转移组 (17例 )MD15 .12± 5 .34(P <0 .0 1)。随访发现 ,MD高表达组与低表达组颈清术后复发率分别为 6 0 %和12 5 % (P <0 .0 1)。舌原发灶复发 8例MD为 45 .5 7± 6 .2 6 ,比无复发组 2 8例MD2 0 .35± 4.13高二倍多 (P <0 .0 1)。结论　肿瘤内血管形成与舌癌的复发转移密切相关 ,而与病理分级及临床分期无关。因此瘤内MD可作为判定舌癌预后的独立指标。