持续皮下输注赖脯胰岛素治疗老年非初诊2 型糖尿病患者临床观察

目的:观察比较持续皮下输注赖脯胰岛素与常规注射预混赖脯胰岛素对老年非初诊2型糖尿病患者的疗效与安全性。方法:将58例老年2型糖尿病患者随机分为观察组(29例)与对照组(29例),观察组用赖脯胰岛素经胰岛素泵持续皮下输注(CSI-I),对照组用精蛋白锌重组赖脯胰岛素25注射液,2次/d,常规皮下注射。两组患者均给予糖尿病教育、饮食控制及适量运动,共治疗2周。比较治疗前后两组患者的血糖、胰岛素用量、血糖达标时间以及低血糖发生率。结果:治疗后两组患者空腹血糖、餐后血糖均较治疗前下降(P<0.05),观察组血糖达标时间、胰岛素用量均明显低于对照组(P<0.05)。两组低血糖发生率无明显差异。结论:持续皮下输注赖脯胰岛素具有较好的疗效与安全性,是控制老年非初诊2型糖尿病患者较佳的方法。     

Trypanosoma cruzi: distinct patterns of infection in the sibling caviomorph rodent species Thrichomys apereoides laurentius and Thrichomys pachyurus (Rodentia, Echimyidae)

Thrichomys apereoides, a caviomorph rodent species common in a highly endemic area for Chagas disease in Brazil, may act as reservoir of the parasite. However, no information is available concerning its sibling species Thrichomys pachyurus, found in the Pantanal region, where Trypanosoma cruzi is found only in the enzootic cycle. We followed up the cross infection of these cryptic species with two isolates derived from naturally infected T. pachyurus and Thrichomys apereoides laurentius. No regional co-adaptation between Thrichomys species and the regional isolates were noticed. However, significant differences in the outcome of the infection were observed. T. a. laurentius was more resistant than T. pachyurus, as expressed by lower parasitemia and less histopathological damage. The routine biochemical markers used for laboratory rodents were unsuitable for follow up of infection in Thrichomys spp, since they did not correlate with the histopathological findings or allowed the kinetic follow-up of tissue colonization by the parasite.     

The mechanism of ABCG5/ABCG8 in biliary cholesterol secretion in mice

The main player in biliary cholesterol secretion is the heterodimeric transporter complex, ABCG5/ABCG8, the function of which is necessary for the majority of sterols secreted into bile. It is not clear whether the primary step in this process is flopping of cholesterol from the inner to the outer leaflet of the canalicular membrane, with desorption by mixed micelles, or decreasing of the activation energy required for cholesterol desorption from the outer membrane leaflet. In this study, we investigated these mechanisms by infusing Abcg8(+/+), Abcg8(+/-), and Abcg8(-/-) mice with hydrophilic and hydrophobic bile salts. In Abcg8(-/-) mice, this failed to substantially stimulate biliary cholesterol secretion. Infusion of the hydrophobic bile salt taurodeoxycholate also resulted in cholestasis, which was induced in Abcg8(-/-) mice at a much lower infusion rate compared with Abc8(-/-) and Abcg8(+/-) mice, suggesting a reduced cholesterol content in the outer leaflet of the canalicular membrane. Indeed, isolation of canalicular membranes revealed a reduction of 45% in cholesterol content under these conditions in Abcg8(-/-) mice. Our data support the model that ABCG5/ABCG8 primarily play a role in flopping cholesterol (and sterols) from the inner leaflet to the outer leaflet of the canalicular membrane.     

Dose-dependent effects of peptide YY(3-36) on conditioned taste aversion in rats

We used a conditioned taste aversion test to assess whether PYY(3-36) reduces food intake by producing malaise. Two-hour IV infusion of PYY(3-36) (8, 15, and 30 pmol/kg/min) at dark onset in non-food-deprived rats produced a dose-dependent inhibition of feeding and a conditioned aversion to the flavored chow paired with PYY(3-36) infusion. In food-deprived rats, PYY(3-36) at 2 and 4 pmol/kg/min inhibited intake of a flavored saccharin solution without producing conditioned taste aversion, whereas higher doses (8 and 15 pmol/kg/min) inhibited saccharin intake and produced taste aversion. These results suggest that anorexic doses of PYY(3-36) may produce a dose-dependent malaise in rats, which is similar to that reported for PYY(3-36) infusion in humans. Previous studies have shown that PYY(3-36) potently inhibits gastric emptying, and that gut distention can produce a conditioned taste aversion. Thus, PYY(3-36) may produce conditioned taste aversion in part by slowing gastric emptying.     

CCK-8 induces fever-like regulated hyperthermia and symptoms of sickness behavior in mice: A biotelemetric study

In earlier studies it has been found that rats respond to intracerebroventricular (i.c.v.) injection of cholecystokinin-octapeptide (CCK-8) with a febrile response characterized by rises of heat production and core temperature together with tail-skin vasoconstriction mediated by CCK2 receptors. Biotelemetric investigations of the same species have additionally shown that CCK-induced fever is accompanied by decreased locomotor activity. Similar data for mice have not been reported so far. In the present studies C57BL/6 mice were infused i.c.v. for 3 days with CCK-8 to see effects on body core temperature, locomotor activity, food intake and body weight. Biotelemetric monitoring disclosed a rise in daylight core temperature and a fall of night-time locomotor activity both lasting beyond the time of i.c.v. infusions. Food intake was suppressed only during infusion, while a significant decrease of body weight was sustained after the end of CCK-8 infusion. It is concluded that similar to rats mice also respond to i.c.v. infusion of CCK-8 with a fever-like (regulated) hyperthermia and some components of sickness behavior as measured by biotelemetry, and thus a CCK-mediated mechanism may contribute to fever genesis also in mice.     

棕榈酸的组织吸收分布及对骨骼肌胰岛素抵抗的影响

脂肪酸代谢紊乱是Ⅱ型糖尿病的主要致病因素之一。棕榈酸是血液中含量最高的游离脂肪酸。我们建立了大鼠颈静脉置管输注棕榈酸的模型,发现血液中的大部分棕榈酸被骨骼肌组织所吸收。以棕榈酸处理的C2C12骨骼肌细胞为实验模型发现,棕榈酸进入骨骼肌细胞后的中间代谢产物(磷脂和甘油二酯)的累积,会造成内质网应激及胰岛素抵抗。提示血液中棕榈酸含量的升高可能通过骨骼肌的胰岛素抵抗机制,影响Ⅱ型糖尿病的发生和发展。     

肝硬化食管胃底静脉曲张破裂出血患者治疗中限制输血量对疗效的影响

目的：研究限制输血输液量在肝硬化食管胃底静脉曲张破裂出血患者治疗中的疗效。方法：将98例患者随机分为两组。治疗组（55例）采用限制输血输液量方法进行治疗,同时进行其它常规止血治疗。对照组（43例）采用相对无限制大量输血输液方法治疗,余治疗方法同治疗组。分别观察两组患者24h、48h、72h内出血停止情况和总有效率。结果：治疗组患者24h、48h、72h内出血停止例数和总有效率明显高于对照组患者。P〈0．01。结论：限制输血输液量在治疗肝硬化食管胃底静脉曲张破裂出血中的止血率高,其作用明显优于相对无限制输血输液量对其治疗的疗效。     

Brain cooling maintenance with cooling cap following induction with intracarotid cold saline infusion: a quantitative model

Intracarotid cold saline infusion (ICSI) is potentially much faster than whole-body cooling and more effective than cooling caps in inducing therapeutic brain cooling. One drawback of ICSI is hemodilution and volume loading. We hypothesized that cooling caps could enhance brain cooling with ICSI and minimize hemodilution and volume loading. Six-hour-long simulations were performed in a 3D mathematical brain model. The Pennes bioheat equation was used to propagate brain temperature. Convective heat transfer through jugular venous return and the circle of Willis was simulated. Hemodilution and volume loading were modeled using a two-compartment saline infusion model. A feedback method of local brain temperature control was developed where ICSI flow rate was varied based on the rate of temperature change and the deviation of temperature to a target (32 °C) within a voxel in the treated region of brain. The simulations confirmed the inability of cooling caps alone to induce hypothermia. In the ICSI and the combination models (ICSI and cap), the control algorithm guided ICSI to quickly achieve and maintain the target temperature. The combination model had lower ICSI flow rates than the ICSI model resulting in a 55% reduction of infusion volume over a 6 h period and higher hematocrit values compared to the ICSI model. Moreover, in the combination model, the ICSI flow rate decreased to zero after 4 h, and hypothermia was subsequently maintained solely by the cooling cap. This is the first study supporting a role of cooling caps in therapeutic hypothermia in adults.     

不同时间脂肪乳输注对大鼠葡萄糖输注率的影响

目的观察不同时间脂肪乳输注使血浆游离脂肪酸（FFA）升高对大鼠葡萄糖输注率（GIR）的影响。方法分别给大鼠输注脂肪乳2、5、7和48 h,行高胰岛素-正血糖钳夹试验评价葡萄糖输注率,测定血浆葡萄糖、FFA。结果与生理盐水输注组比较,2 h脂肪乳输注使血浆FFA升高了2倍（P〈0.01）,GIR下降27%（P〈0.05）,脂肪乳输注5 h GIR降低了52%（P〈0.01）,7 h GIR降低56%（P〈0.01）,输注48 h脂肪乳GIR降低58%（P〈0.01）,5 h组7、h组及48 h脂肪乳输注组间GIR差异没有统计学意义。结论大鼠输注脂肪乳使FFA浓度达到基础值的3倍左右,可复制出脂毒性胰岛素抵抗的模型,而且胰岛素抵抗达到一定程度后保持恒定。     

High-performance liquid chromatographic separation and identification of polyphenolic compounds from the infusion of Davilla elliptica St. Hill

The isolation of polyphenolic compounds from an infusion of the Brazilian plant Davilla elliptica (Dilleniaceae), used as tea by virtue of its digestive properties, is described. An improved preparative HPLC method was used in order to isolate pure polyphenols from the complex mixture. Liquid-liquid extraction and solid-phase extraction were employed to minimise the interference of polymeric compounds and to provide an enriched fraction of the compounds of interest. The identification of the isolated compounds was performed using analytical HPLC as well as direct injection electrospray ionisation ion trap tandem mass spectrometry (ESI-IT-MS/MS). The high flavonoid content suggests that D. elliptica may be a promising source of compounds to produce natural phytomedicines.