Aging syndrome genes and premature coronary artery disease

Background  

Vascular disease is a feature of aging, and coronary vascular events are a major source of morbidity and mortality in rare premature aging syndromes. One such syndrome is caused by mutations in the lamin A/C (LMNA) gene, which also has been implicated in familial insulin resistance. A second gene related to premature aging in man and in murine models is the KLOTHO gene, a hypomorphic variant of which (KL-VS) is significantly more common in the first-degree relatives of patients with premature coronary artery disease (CAD). We evaluated whether common variants at the LMNA or KLOTHO genes are associated with rigorously defined premature CAD.     

Patient satisfaction with telemedicine in home health services for the elderly

In a pilot study of telemedicine in home health services (HHS) for elderly patients, we implemented and evaluated a telemedicine system with a 33-kbs narrow-band approach to determine its effectiveness in providing quality services. Fifty patients were selected for the study. We found that telemedicine was effective in terms of reducing the number of clinic visits and achieving patient satisfaction. The average number of clinic visits per month was significantly decreased from 0.64 to 0.42 (p < 0.05) after the use of telemedicine. 72% of patients were satisfied with telemedicine, but only patient location showed a significant difference for patient satisfaction (p < 0.05). Patients in their homes (82%) were more satisfied than patients in nursing homes (50%). Of four types of services provided, medical consultation (100%) was the most highly satisfactory service with telemedicine, followed by physical therapy (83.3%). Although the satisfaction scores did not indicate a significant difference in the system characteristics, the quality of verbal communication appeared to be a more important factor in influencing patient satisfaction than set-up time or quality of image. A computer-based patient record was also developed to view a patient summary and to document encounters at the patient's home. Since the system is a low-cost approach that is easy to interface with a notebook computer, it can support various other HHSs.     

Association of SIGNR1 with TLR4-MD-2 enhances signal transduction by recognition of LPS in gram-negative bacteria

SIGNR1, a member of a new family of mouse C-type lectins, is expressed at high levels in macrophages (Mphi) within the splenic marginal zone, lymph node medulla, and in some strains, in peritoneal cavity. We previously reported that SIGNR1 captures gram-negative bacteria, such as Escherichia coli and Salmonella typhimurium, as well as Candida albicans. We have now investigated the precise ligands and innate responses that involve SIGNR1. The interaction of SIGNR1 with FITC-dextran and E. coli was completely inhibited by LPS from E. coli and Salmonella minnesota. Using LPS from various types of rough mutants of Salmonella, we found that SIGNR1 primarily recognizes oligosaccharides in the non-reductive end of the LPS core region. In transfectants, expression of SIGNR1 enhanced the oligomerization of Toll-like receptor (TLR) 4 molecules as well as the degradation of IkappaB-alpha after stimulation with E. coli under low-serum conditions. The enhanced TLR4 oligomerization was inhibited by pre-treatment of the cells with anti-SIGNR1 mAb or with mannan. A physical association between SIGNR1 and the TLR4-MD-2 complex was also observed by immunoprecipitation. Finally, we found that transfection of SIGNR1 into the macrophage-like RAW264.7 cells resulted in significant augmentation of cytokine production. These results suggest that SIGNR1 associates with TLR4 to capture gram-negative bacteria and facilitate signal transduction to activate innate M responses.     

The effect of the repeated subcultures of Helicobacter pylori on adhesion,motility, cytotoxicity,and gastric inflammation

In vitro subcultures of bacteria can lead to genetic and phenotypic changes. This study aimed at investigating the effect of repeated subcultures on the adhesion, motility, cytotoxicity, and gastric inflammation caused by Helicobacter pylori. H.pylori SS1 strain was subcultured 64 times on agar plates containing Brucella broth and 5% bovine calf serum. The adhesion, motility, cytotoxicity, and gastric inflammation produced in Mongolian gerbils were compared between the first and 64th subcultured strain. The adhesion rates, following 3 hr exposure of AGS cells to either the first strain or the 64th-transferred strain, were 21% and 12%, respectively. The motility of the 64th-transferred strain decreased significantly when compared to the 1st strain (9.1 mm vs. 15.1 mm). The cytotoxicity index tended to be higher in the first strain than in the 64th-transferred strain (73.7% vs. 69.2%). The initial infection rate on the gerbils showed no difference between the two strains. However, chronic gastric inflammation of the first strain-infected gerbils was somewhat more severe than that of the 64th-transferred strain-infected gerbils. Therefore, the use of repeatedly subcultured strains of H. pylori in virulence experiments can lead to different results from those of the original strain.     

Degradation behaviour in vitro for poly(D,L-lactide-co-glycolide) as drug carrier

Biodegradable polymers have been extensively investigated because of regulating drug release rate easily, obviating the need to remove the device, and good biocompatibility. Among the biodegradable polymers currently under investigation, poly(D,L-lactide-co-glycolide) (PLGA) copolymers are the most widely studied because of their long history of safe clinical use as drug carrier. 50 : 50 PLGA was used as a model degradable polymer in this study to investigate the degradation behaviour on drug release from bulk degradable polymers in vitro. 5-fluorouracil (5-FU) was used as a model drug. Molecular weight change, residual mass, water uptake, morphological change of PLGA wafers, and pH of release test medium were characterized to investigate the effect of polymer degradation on drug release. The release rate of 5-FU increased with the increase of 5-FU loading amount and the release profiles of 5-FU irrespective of 5-FU loading amount followed near first order release kinetics.     

High-voltage-activated calcium current in developing neurons is insensitive to nifedipine

We have analyzed the effect of nifedipine on the macroscopic high-threshold, voltage-activated (HVA) calcium current in four cell types: postnatal rat Purkinje and dorsal root ganglion (DRG) neurons, embryonic chick DRG neurons, and adult cat ventricular myocytes. As is consistent with previous reports, nifedipine reduced HVA current in myocytes in a voltage-sensitive manner. Analysis of nifedipine actions on neurons, however, was compromised by slow inactivation of the current at holding potentials between –80mV and –40 mV. The slow inactivation was voltage-dependent, irreversible after 5 min, and contributed to rundown of the current. At –40 mV, slow inactivation displayed two time constants: 12±8 s and 7±4 min. When slow inactivation was taken into account, we found no evidence for a nifedipine-sensitive component of the HVA current in these neurons. Consistent with previous studies, DRG neurons were reduced irreversibly by -conotoxin, whereas cardiac and Purkinje cells were unaffected. Our biophysical and pharmacological results are consistent with two types of neuronal HVA currents (N type and P type) in developing neurons that are distinct from cardiac HVA currents (L type).     

An individualized teaching program for atherosclerotic risk factor reduction in patients with myocardial infarction

This study was conducted to evaluate the effect of a teaching program on patients with myocardial infarction. Forty-five patients were randomly selected 22 were assigned to a teaching group and 23 to a control group. An individualized teaching program was delivered to the teaching group during the hospitalization period. It covered aspects such as: the characteristics of heart disease, the anatomy and physiology of the heart, risk factors of atherosclerosis, medication and diet and exercise therapy. When these subjects were discharged to their homes, they received regular supportive care via telephone or mail for 12 weeks. Atherosclerotic risk factors, including, smoking, exercise, blood lipid profile and BMI were measured before and after the teaching program. Post-testing revealed that the numbers of those who exercised and the number of non-smokers were significantly higher in the teaching group than in the control group. Increased HDL cholesterol (High-Density Lipoprotein cholesterol) was significantly greater in the teaching group than in the control group. The above findings suggest that this individualized teaching program might be helpful at reducing the risk factors of atherosclerosis in myocardial infarction patients.     

神经元自发放电混沌节律中的高阶非稳定周期轨道

0　引言　在神经元上记录到的放电多数为不规则模式 ,这类节律是否服从确定性混沌规律一直是研究的热点 .混沌系统生成的奇怪吸引子包含无穷多的非稳定周期轨道 (UPOs) ,它们构成了吸引子的骨架 [1 ] .运用实验数据集的非稳定周期轨道检测 ,可辨别节律中存在的确定性和可预报性 [2 ] .我们分析大鼠坐骨神经结扎损伤模型的起步点的不规则节律 ,运用UPOs分析确认其混沌性 ,进一步分析高阶的非稳定周期轨道 .1　方法1.1　实验性起步点放电的采集　实验选择成年 SD大鼠 (体质量 15 0～ 30 0 g) ,按文献 [3]所述制备坐骨神经慢性结扎损伤动物…