慢性乙型肝炎肝细胞凋亡与肝脏微循环障碍的关系研究

目的研究慢性乙型肝炎肝细胞凋亡与肝脏微循环障碍的关系。方法采用TUNEL法检测肝细胞的凋亡率,同时采用透射电镜观察肝细胞超微结构的变化和肝窦微循环结构的改变。结果慢性乙型肝炎肝细胞凋亡率显著增加,细胞膜皱缩并分裂成多个凋亡小体,肝窦内皮细胞窗孔减小减少并伴有狄氏腔胶原沉积和基底膜形成,同时可发现WP小体。结论慢性乙型肝炎肝细胞凋亡是肝脏微循环障碍的重要促进因素。     

Identification and characterization of Trichoplusia ni furin truncated mutant

We report a new prohormone convertase gene of insect origin, Trichoplusia ni furin, which was cloned from BTI-Tn-5B-4 (Tn5) insect cells. We constructed a truncated mutant that lacked Cys-rich repeated segments. Using baculovirus expression system and standard enzymatic assay, we obtained recombinant Tn furin and evaluated aspects of its function.     

Neotropical Copestylum (Diptera,Syrphidae) breeding in Agavaceae and Cactaceae including seven new species

We studied 42 species of saprophagous, Neotropical Copestylum (Diptera, Syrphidae) reared from decaying Cactaceae and Agavaceae. Thirty‐three species were reared during fieldwork in Bolivia, Costa Rica, Ecuador, Mexico, Peru, and Trinidad from 1998–2007. Nine species came from museum and private collections. Seven were new species. We describe these new species and the third stage larva and/or puparium and breeding sites of 40 species. Not described are two apparent species related to Copestylum apicale (Loew, 1866) reared from Cactaceae. Resolution of their status was beyond the scope of this paper but reference is made to their distinctive larval morphology. Based on early stage characters all reared species can be placed in ten species groups, all but three of which have been recognized previously on the basis of adult characters. A high level of congruence was found between adult and larval characters in terms of these species groups. Eight of the groups appear to be related closely and may represent a monophyletic lineage within Copestylum that has diversified in xeric habitats. Early stage morphology varied within and amongst groups but two trends in functional morphology are recognizable. One trend is towards feeding in watery decay and the other towards feeding in firmer decay. The latter trend is characterized by species that scoop food and use grinding mills in their head skeletons to break it up. They also have armoured thoraces with varying arrangements of sclerotized spicules or stiffened setae for gripping and protection during tunnelling, a short anal segment, and a short posterior breathing tube for protecting the openings. The former trend is characterized by species with opposite and contrasting features. They filter food and have well‐developed pre‐oral setal filters but they lack grinding mills or only have poorly developed grinding mills. They have reduced thoracic armature, elongate anal segments, and posterior breathing tubes which facilitates simultaneous feeding and respiration. Comparison with 23 Copestylum species reared from bromeliads (Bromeliaceae) suggests a common pattern of diversification in that species groups with the largest body sizes are more specialized.     

The 1.4 A crystal structure of the large and cold-active Vibrio sp. alkaline phosphatase

Alkaline phosphatase (AP) from the cold-adapted Vibrio strain G15-21 is among the AP variants with the highest known k(cat) value. Here the structure of the enzyme at 1.4 A resolution is reported and compared to APs from E. coli, human placenta, shrimp and the Antarctic bacterium strain TAB5. The Vibrio AP is a dimer although its monomers are without the long N-terminal helix that embraces the other subunit in many other APs. The long insertion loop, previously noted as a special feature of the Vibrio AP, serves a similar function. The surface does not have the high negative charge density as observed in shrimp AP, but a positively charged patch is observed around the active site that may be favourable for substrate binding. The dimer interface has a similar number of non-covalent interactions as other APs and the "crown"-domain is the largest observed in known APs. Part of it slopes over the catalytic site suggesting that the substrates may be small molecules. The catalytic serines are refined with multiple conformations in both monomers. One of the ligands to the catalytic zinc ion in binding site M1 is directly connected to the crown-domain and is closest to the dimer interface. Subtle movements in metal ligands may help in the release of the product and/or facilitate prior dephosphorylation of the covalent intermediate. Intersubunit interactions may be a major factor for promoting active site geometries that lead to the high catalytic activity of Vibrio AP at low temperatures.     

Long-term risk of receiving a total hip replacement in cancer patients

Aim: To investigate whether cancer patients have an increased risk of receiving a total hip replacement compared to the standard population of Norway. Materials and methods: By linking of The Cancer Register of Norway and The Norwegian Arthroplasty Register we obtained information on cancer diagnoses (type, date of diagnosis), total hip arthroplasties and date of death for all patients living in Norway. This includes 741,901 patients categorized into three groups: 652,197 patients with at least one cancer diagnosis but no hip arthroplasties, 72,469 patients with at least one hip arthroplasty but no cancer diagnosis and 17,235 patients who have at least one cancer diagnosis and at least one hip arthroplasty. Within this latter group, 8563 individuals had been diagnosed with cancer prior to a total hip arthroplasty. Statistical methods applied in this study were Cox interval censored regression models and standardized incidence ratios (SIR). Results: Cancer patients had a slightly increased risk of receiving a total hip arthroplasty compared to the Norwegian population (SIR = 1.15 (95% CI, 1.12–1.17)). For primary tumours located cranially to the pelvic area there was no significant increase in risk for hip arthroplasty. An exception was breast cancer (SIR = 1.13 (95% CI 1.08–1.18)). Cancer located in the pelvic region (SIR = 1.20 (95% CI 1.16–1.24)), malignant lymphoma (SIR = 1.30 (95% CI 1.15–1.46)) and leukaemia (SIR = 1.17 (95% CI 1.01–1.34)) had an increased risk for receiving a total hip arthroplasty. Conclusion: Cancer survivors, mainly those with pelvic and lympho-hematological malignancies, have a small statistically significant increase in risk for receiving total hip arthroplasty.     

BR-TRG-Ⅰ型体腔热灌注治疗系统安全性评估的动物实验

目的探讨应用BR-TRG-I型体腔热灌注治疗系统进行持续循环腹腔热灌注治疗（continuous circulatory hyperthermic intraperitoneal perfusion treatment,CCHIP）对实验动物的生命体征、肝肾功能及内脏器官病理形态的影响。方法选用家猪作为实验动物,应用BR-TRG-I型体腔热灌注治疗系统建立CCHIP动物模型,分别用44℃、45℃的设定温度进行CCHIP。在CCHIP期间记录实验动物的生命体征变化;CCHIP前及治疗后1d、3d、7d和14d抽取外周血液保存备检;CCHIP结束后即刻及2周后处死动物,观察内脏器官的大体形态学改变,切取肝、肾、小肠等器官进行病理检查。结果44℃CCHIP持续1.5h对猪的生命体征、肝肾功能无明显影响,肝、肾、小肠等脏器损伤较轻,2周后恢复正常;45℃CCHIP持续1.5h对猪的生命体征影响严重,肝肾功能损害持续2周尚不能恢复正常,肝、肾、小肠等脏器病理损伤明显。结论44℃温度CCHIP1.5h安全可行,可以作为CCHIP的安全温度;45℃温度CCHIP1.5h可对实验动物肝肾功能造成严重损害,不适合作为CCHIP的治疗温度。     

Pin1和Cyclin D1在人类5种常见肿瘤中的表达及其意义

目的研究人类的肽基脯氨酰异构酶(Pin1)在人类几种重要的肿瘤(肺癌、前列腺癌、乳腺癌、宫颈癌和胃癌)中的表达及与细胞周期蛋白CyclinD1的关系,并探讨它们在肿瘤的发病机制、诊断和治疗中的意义。方法随机收集33例正常组织和171例癌组织(包括37例肺癌、35例前列腺癌、31例乳腺癌、36例宫颈癌和32例胃癌)。采取免疫组织化学Envision法显示Pin1和CyclinD1的表达。结果Pin1和CyclinD1在正常组织中不表达或者低表达,而在各种癌组织中有普遍性的高表达,在肺癌组织、前列腺癌组织、乳腺癌组织、胃癌组织和宫颈癌组织中,Pin1的表达率分别为48·7%、65·7%、48·4%、15·6%和69·4%,CyclinD1的表达率分别为56·8%、60·0%、54·8%、40·6%和58·3%。Pin1和CyclinD1在癌组织中的表达明显高于正常组织中的表达(P<0·05)。Pin1和CyclinD1蛋白在肺癌、前列腺癌、乳腺癌和宫颈癌中表达呈显著正相关(P<0·05)。而Pin1和CyclinD1蛋白在胃癌中的表达相关性不显著(P>0·05)。结论Pin1和CyclinD1在多种肿瘤的发生、发展过程中具有重要作用,如肺癌、前列腺癌、乳腺癌、宫颈癌和胃癌,Pin1与细胞周期代谢或调控有关。Pin1在某些肿瘤(如肺癌、前列腺癌等)中可作为肿瘤标记的参考指标。     

Strobilanthes crispus attenuates renal carcinogen, iron nitrilotriacetate (Fe-NTA)-mediated oxidative damage of lipids and DNA

This study was aimed to evaluate the effect of Strobilanthes crispus extract for possible protection against lipid peroxidation and DNA damage induced by iron nitrilotriacetate (Fe-NTA) and hydrogen peroxide (H₂O₂). Fe-NTA is a potent nephrotoxic agent and induces acute and subacute renal proximal tubular necrosis by catalyzing the decomposition of H₂O₂-derived production of hydroxyl radicals, which are known to cause lipid peroxidation and DNA damage. Incubation of postmitochondrial supernatant and/or calf thymus DNA with H₂O₂ (40 mM) in the presence of Fe-NTA (0.1 mM) induces lipid peroxidation and DNA damage to about 2.3-fold and 2.9-fold, respectively, as compared to control (P < 0.05). In lipid peroxidation protection studies, S. crispus treatment showed a dose-dependent inhibition (45–53% inhibition, P < 0.05) of Fe-NTA and H₂O₂ induced lipid peroxidation. Similarly, in DNA damage protection studies, S. crispus treatment also showed a dose-dependent inhibition (18–30% inhibition, P < 0.05) of DNA damage. In addition, the protection was closely related to the content of phenolic compounds as evident by S. crispus extract showing the value of 124.48 mg/g total phenolics expressed as gallic acid equivalent (GAE, mg/g of extract). From these studies, it is concluded that S. crispus inhibits peroxidation of membrane lipids and DNA damage induced by Fe-NTA and H₂O₂ and possesses the potential to be used to treat or prevent degenerative diseases where oxidative stress is implicated.