Frailty is a geriatric syndrome characterized by increased vulnerability to degenerative changes and various chronic diseases, and is associated with a series of negative clinical events.The pathogenesis of frailty is unclear, and population cohort and observational research has made progress in understanding the biological characteristics of frailty, especially about the hypothalamic-pituitary-adrenal axis and neuroendocrine dysfunction, chronic inflammation and immune system ageing, cell senescence, energy metabolism dysfunction, social environmental psychological factors and chronic diseases, among others.This article reviews the pathogenesis of frailty in the elderly.

This article introduces the current status of Chinese institutes for medical devices testing, and analyses the misunderstanding in extending the testing capacities for the provincial institutes for medical devices. Then, some suggestions are given to orientate themselves in extending capacities. Finally, these specific procedures on extending the testing capacities are presented.
China ; Equipment and Supplies ; standards

OBJECTIVE： To find out the change of drug resistance of Shigella shigae in our hospital during recent five years.METHODS： To collect the stool of suspectable cases of clinical bacillary dysentery and to carry out bacterial culture and drug sensitive test.RESULTS： The resistance rates of Shingella shigae to ampicillin and fluoroquinolones raised obviously， but the bacilli were still sensitive to amikacine and cefobid.CONCLUSION： It is important to strictly control the indications in using antibiotics and to prevent the emergence of drug resistance of bacteria.

ObjectiveTo investigate the application effect of Delphi method to establish the preoperative visit mode. MethodsTaking the Delphi method to establish the standardized procedures of preoperative visit.The average length of stay,hospital costs and satisfaction degree of patients before and after application of standardized procedures of preoperative visit were compared. ResultsThe study showed that after taking the Delphi method to establish the preoperative visit mode,the patients' hospital stay for the same type of surgery,treatment costs and satisfaction degree of patients improved significantly than those before.The differences before and after treatment were significant. ConclusionsUsing Delphi method to establish a standardized procedures of preoperative visit has the advantage of strong target,strong representation,high degree of authority.It takes advantage of the excellent medical care experience and provides uniform and stable preoperative preparation work.It lays a foundation for patients to get better medical care and is worthy of clinical application.

During last decade, gold nanoparticled (AuNPs)-based assays have been well-developed and widely used in biological analysis and biomedical detection because AuNPs have unique physical and chemical properties which depend on the size, shape and degree of aggregation.The AuNPs-based assays have already been employed for detecting practical samples with high simplicity and selectivity.This review discusses the recently development of the synthesis and biological molecular functionalisation of AuNPs and their applications on the heavy metallic cations, small organic compounds, nucleic acids and proteins detection and cellular analysis.

Objective To investigate the pathological features and significance of m yocardial contraction band necrosis in sudden cardiac death. Methods Using HE and PTA Hstaining, the distribution sites and pathological features of m yocardial contraction band necrosis were observed. The data were analyzed accord-ing to the extent of necrosis. Results The locations, pathological features and the extent of necrosis were sim ilar in different sudden death cases. The locations were related with sites of m yocardial dam age. The papillary m uscles of left ventricular were m ost occurred, followed by the anterior wall of left ventricular. In the sudden death cases caused by stress cardiom yopathy, the extent of m yocardial contraction band necrosis was lighter than the others. Most cases were predom inantly level 1, the others were level 2. Conclusion Used as the diagnosis basis of acute m yocardial ischem ia, the m yocardial contraction band necrosis has im portant significance to determ ination of death.

Objective To investigate the correlation between orexin A and the serine proteinase inhibitor vaspin in obese rats with insulin resis?tance(IR)induced by high?fat diet and elaborate the possible action mechanism of orexin involvement in fat metabolism in IR pathological process. Methods A total of 75 4?week?old male Sprague?Dawley rats were randomly divided into the normal dietary group(NC group,n=20)and the high?fat dietary group(HF group,n=55)to establish the model of obese rats with IR,the euglycemic insulin clamp technique was used to determine re?lated indicators of insulin resistance and lipid metabolism. The rats were treated with orexin A(1×10-8?1×10-6 mol/L)by hypodermic injection. The serum levels of orexin A and vaspin in rats were detected with enzyme linked immunosorbent assay. Results After 6 weeks of high?fat diet,the se?rum glucose,insulin,TC,TG and LDL?C were increased significantly in HF group than in NC group,while GIR60~120 in obese rats was decreased significantly[(16.31 ± 1.54)vs(30.22 ± 2.76)mg/(kg · min),P<0.05]. The serum vaspin level was increased 177.08%in HF group compared with NC group(P<0.05). With hypodermic injection of orexin A(1×10-8 mol/L,1×10-7 mol/L and 1×10-6 mol/L),the levels of serum vaspin in?creased 25.00%,68.75%,and 120.83%in NC group and increased 7.52%,24.06%,and 40.60%in HF group. There was a positive correlation be?tween vaspin and orexin A,glucose,insulin,TC,TG,and LDL?C(r1=0.482,P1=0.02,r2=0.515,P2=0.02,r3=0.303,P3=0.04,r4=0.388,P4=0.03,r5=0.255,P5=0.04,r6=0.253,P6=0.04)and a negative correlation between vaspin and HDL?C(r=-0.226,P=0.04)in obese rats with IR. Conclusion High?fat diet can induce insulin resistance and obesity in rats,and orexin A is closely correlated to vaspin in obese rats with insu?lin resistance. Orexin A increases serum vaspin expression and thus involves in onset of insulin resistance in obese rats.

A gold nanoparticle ( GNP)-based dynamic light scattering ( DLS) assay has been developed for detecting mercury ion ( Hg2+) in aqueous solution. The GNPs are able to maintain monodisperse state in relative high ionic strength ( 0. 1 mol/L NaCl ) aqueous solution because Hg2+ aptamer 5’-TTTCTTCTTTCTTCCCCCCTTGTTTGTTGTTT-3’( Probe DNA ) can adsorb on the GNP surface by electrostatic interaction. In the presence of Hg2+, the Probe DNA molecules easily desorb from GNP surface because of T-Hg2+-T formation. The unprotected GNPs form aggregates in 100 mmol/L NaCl solution, resulting in increased significantly the average hydrodynamic diameter of GNPs. Under the conditions of pH 7. 43, 110 nmol/L aptamer, 100 mmol/L NaCl and 30 minutes incubation time of Hg2+with aptamer, the difference of average hydrodynamic diameter (△D ) of GNPs was increased linearly with logarithm of Hg2+concentration over the range from 0. 1 nmol/L to 5 μmol/L, with a detection limit of 0. 1 nmol/L. Moreover, satisfactory results were obtained when the proposed method was applied to detect Hg2+ in real samples.

Peroxisome proliferators-activated receptors(PPARs)are ligand activated transcriptional factors and belonging to the nuclear receptor superfamily.PPARs play important roles in the regulation of lipid and glucose metabolism,energy homeostasis,cell proliferation,differentiation and reproduction.Furthermore,PPARs agonists were closely correlated to atherosclerosis and involved in delaying the formation of atherosclerosis.

Objective To compare clinical effects among three techniques of multifetal pregnancy reduction(MFPR) guided by transvaginal ultrasonography through vaginal approach.Methods Under the guidance of transvaginal B-ultrasonography,99 cases of multiple pregnancy following assisted reproductive technique underwent three different methods of embryo reduction: drug injection directly to the pregnancy sac(Drug Group),simple embryonic bud aspiration(Aspiration Group),and combined use of drug and aspiration(Combination Group).Results The gestational age at the procedure ranged 41~88 days(mean,58.9?8.7 days).The success rate of the procedure on one session was 100%(99/99).Short-term outcomes included 3 cases of abortion(3.0%).On continuing follow-up observations in 73 cases,the incidences of abortion and premature delivery were 11%(8/73) and 12%((9/73)),respectively.No statistical differences were seen among the three groups in rates of abortion,premature delivery,and full-term delivery(?~2=1.131,P=0.889).In the Aspiration Group,however,the exposure time to B-ultrasound and the operative time were significantly shorter than those in the other two groups.The gestational age at the procedure was 61.7?8.2 days in the Drug Group,48.8?2.7 days in the Aspiration Group,and 56.7?7.2 days in the Combination Group,respectively,with significant differences between the Aspiration Group and other two groups(F=19.36,P=0.000).The number of embryos reduced was associated with pregnancy outcomes: the abortion rate was remarkably higher in patients receiving the reduction of more than two embryos than only one embryo(?~2=6.415,P=0.040).Conclusions Ultrasound-guided multifetal pregnancy reduction is a safe,effective and microinvasive procedure.It is recommended that simple embryonic bud aspiration be used for multifetal pregnancy before 7 gestational weeks,combined use of drug injection and aspiration for multifetal pregnancy at 7~9 gestational weeks,and drug injection to the pregnancy sac for multifetal pregnancy after 9 weeks.