Objective To investigate the changing trends in 4 continuous point prevalence surveys of healthcare-as-sociated infection(HAI)in a hospital. Methods The occurrence of HAI among all hospitalized patients were inves-tigated on a given day from 0:00 to 24:00 in May,2006,2008,2010,and 2012 respectively.Results A total of 4 497 patients should be investigated,4 387 (97.55% )patients were actually investigated;184 patients developed 209 times of HAI,point prevalence rate of HAI was 4.19% ,case prevalence rate was 4.76% . Trendχ2 test showed that HAI prevalence rate decreased gradually from 5.56% in 2006 to 2.76% in 2012(χ2= 14.07,P<0.001).The main infection site was lower respiratory tract (55.03% ),followed by urinary tract(14.83% )and upper respiratory tract(9.57% ).The overall usage rate of antimicrobial agents was 38.50% . Trendχ2 test showed that usage rate of antimicrobial agents decreased gradually from 2006 to 2012(χ2= 5.13,P= 0.023);pathogenic detection rate in pa-tients receiving therapeutic and therapeutic plus prophylactic antimicrobial use increased gradually(χ2= 40.81 ,P<0.001);single use of antimicrobial agents increased gradually(χ2= 23.86,P<0.001). The rate of arteriovenous in-tubation ,urinary catheterization ,respirator use,and venous intubation in patients with HAI was significantly higher than those without HAI (27.17% vs 9.80% ,35.33% vs 11.54% ,13.59% vs 4.33% ,84.78% vs 63.24%respectively ,all P<0.001). Conclusion Management of rational use of antimicrobial agents has been achieved re-markably,control of HAI improved continuously;but control of invasive procedure-associated infection need to be intensified,management of rational use of antimicrobial agents should be paid much attention.

A micro droplet generator based on V-shape linear ultrasonic motor was prepared to produce micro droplets with higher accuracy in the field of biochemistry.The device was composed of a micro droplet generator which was driven by the V-shaped linear ultrasonic motor, a three-dimensional displacement platform based on V-shaped linear ultrasonic motor, and a micro droplet separation unit based on the piezoelectric vibrator.The generating part consisted of an ultrasonic motor, a medical syringe, a silica flexible tube and a self-made micro nozzle based on glass.Utilizing the drive controller to drive the linear ultrasonic motor, the slipway pushes forward the syringe and the micro droplet was attached to the glass nozzle.The natural mode of the rod nozzle was excited by the piezoelectric vibrator.The attached droplet was separated from the tip of the nozzle after overcoming the viscous force.The separated droplet fell in a certain range.And the radius of the spherical droplet was calculated.In the experiment, distilled water was used as the initial liquid to investigate the characteristics of the micro droplets produced by the device.The experimental results showed that the droplet was attached to the tip of the micro nozzle which was formed by distilled water under the linear motor.By the vibration of the separation unit, the attached droplets formed the spherical droplets by overcoming the viscous forces in the tip of the nozzle.The radius of spherical droplets generated by this device was less than 40 μm by measuring the size.

Objectives To study the incidence of Trichomonas vaginalis(TV)infection in Chinese male patients with nongonococcal urethritis(NGU),to evaluate the sensitivity and specificity of urine-based and urethral swab polymerase chain reaction(PCR)detection,and to set up a method of non-invasive detection for male TV infection.Methods One hundred and five male NGU patients were collected from the STD clinic.Two urethral swabs were obtained from each patient,one for InPouch TV culture system,the other for PCR;one urine specimen(first-void urine or first-catch urine)was also collected for PCR detection.Culture was considered as the"gold standard".Compared with the culture,the sensitivity,specificity,positive predictive value(PPV)and negative predictive value(NPV)of two PCR detection were calculated.Results The positive rate of InPouch TV system detection was4.76%(5/105);the positive rate of urine-based PCR and urethral swab PCR detection was3.81%(4/105)and4.76%(5/105),respectively.In comparison with the culture,the sensitivity,specificity,PPV and NPV were80%,100%,100%and99%for urine-based PCR and80%,99%,80%and99%for urethral swab PCR.Conclusions TV is one of the etiological agent for male NGU,the positive rate of TV is4.76%in our study.The urine-based PCR detection has a higher sensitivity and specificity and provides a noninvasive method which is feasible in practice.

Objective To investigate the potassium currents of the cardiac pacemaking cells induced and differentiated from rat mesenchymal stem cells (MSCs) modified by HCN4 gene. Methods Identified cardiac pacemaking cells were adopted as the experiment group, and the sinoatrial node cells of original infant rat cultured in the same period were regarded as the control group. Whole cell patch was used to measure the action potential of the pacemaking cells and sinoatrial node cells. Results Action potential of automatic depolarization at dilatation was recorded in both the differentiated cardiac pacemaking cells and sinoatrial node cells. There was no significant difference on amplitudes of resting potential, amplitudes and cycle of action potential [(-50?2.8) vs (-55?5.5),(-60?2.5) vs (-65?2.5),(240?57) ms vs (250?60) ms], but the field potential was much lower in cardiac pacemaking cells than the control group[(-30?2.5) vs (-55?5.5),P

Objective To study the effects of heart ischemia reperfusion on conductive function of atrioventricular node (AVN) in rabbits. Methods Animal models of ischemia reperfusion of AVN were established by ligating and reopening the right coronary artery of rabbits. A total of 60 adult rabbits were divided into control groups ( n =10), right coronary artery occlusion group ( n =10), and ischemia reperfusion groups with ligation of the right artery occlusion for 10, 30, 60 and 120 min respectively ( n =10 for every subgroup). The hemodynamics, His bundle electrography and epicardial electography were carried out and recorded. Results After occlusion of right coronary artery, 94.8% animals in experimental groups were found to have prolonged atrial His interval (AH) ( P

Objective To investigate the effects of electrical stimulation on the differentiation of rat bone marrow mesenchymal stem cells (MSCs) to cardiomyocyte induced by 5-azacytidine in vitro. Methods MSCs from Sprague-Dawley (SD) rats were cultured and passed repeatedly to P3. MSCs were treated with 5-azacytidine (10 ?mol/L) and incubated for 24 h.The induced MSCs were divided to stimulated group and non-stimulated group, and every groups divided by incubated for 1,2,3 and 4 weeks were named as subgroup Ⅰ,Ⅱ, Ⅲ and Ⅳ respectively.MSCs of stimulated group were stimulated for 30 min every day by supra-threshold square biphasic pulses (2 ms duration, 1.5 Hz, 20 ?A), and the stimulation was initiated 1 d after inducing. Light and electronic microscope were used to identify the influences of characteristic morphological of MSCs in every subgroups,and immunocytochemistry was used to identify the expression of ?-actin,cTnT, Cx43 in MSCs. Results The growth of MSCs in stimulated group was better than that of non-stimulated group. MSCs of stimulated group exhibited differentiation into cardiomyocyte-like cell at 1 week after inducing, earlier than that of no-stimulated group (2 weeks). In stimulated subgroup Ⅰ, scattered myogenic structure was observed in the plasma of some cells under electronic microscope, and ?-actin,cTnT expressed in some cells, but not that be observed in non-stimulated subgroup Ⅰ. In cells of stimulated subgroups Ⅱ to Ⅳ, the expression level of ?-actin, cTnT, Cx43 of were all higher than that of non-stimulated subgroups respectively. Conclusion Electrical stimulation (simulating the heart beating) could redound differentiation of rat bone marrow mesenchymal stem cells (MSCs) to cardiomyocyte induced by 5-azacytidine in vitro.

Objective To investigate the effect of calcium/calmodulin-dependent protein kinaseⅡ (CaMK[KG-*6]Ⅱ) inhibitor,KN93 on calcium overloading of atrial muscle cells in neonatal rats and detect the expression of CaMK[KG-*6]Ⅱ. Methods The atrial muscle cells from neonatal rats were primarily cultured for 96 h and then divided into 6 group,control,calcium overloading group,KN93 group (0.5 ?mol/L),low-,moderate-and high-dose of KN93+ calcium overloading group. A model of calcium overloading for atrial muscle cells was established by using calcium ionophore (ionomycin,1.0 ?mol/L). For the later 3 groups,KN93 at doses of 0.25,0.5 and 1.0 ?mol/L was added into the culture medium for 30 min followed by 1.0 ?mol/L ionomycin treatment for another 30 min. The identification of ?-actin was performed by immunofluorescence staining. In the present of Fluo-3/AM (an indicator of calcium),intracellular calcium and the expression of CaMK[KG-*6]Ⅱ were detected under the intervention of KN93 with laser cofocal microscopy and Western blotting respectively. Results More than 90% of cultured cells were positive to ?-actin antibody. Compared with the control group,the fluorescence intensity of intracellular Ca2+ was increased significantly by ionomycin (660.16?108.47 vs 376.12?57.57,P

Objective To develop new methods to cultivate, retrieve and purify mouse mesenchymal stem cells (mMSCs). Methods Bone marrow was collected from 2-month-old Kunming mice by flushing femurs and tibias with complete medium of DMEM-LG. Cells were plated in a Petri dish. After 24 hours, non-adherent cells were removed by two to three washes with PBS, adherent cells were further cultured in complete medium and retrieved by trypsinisation with 0.25% trypsin for 5 min at 37 ℃. The treated adherent cells were cultivated with 3?dilution for further generations. CD11b-negative cells were retrieved from the collected adherent cells of 3rd generation by using immunomagnetic microbeads, and continued to be cultured in complete medium. After the cultured cells were retrieved, their morphology and their ability of osteoblastic differentiation and adipocytic differentiation were examined. Results Most of mMSCs from 1st generation were of shuttle shape, some of irregular shape. After treatment with magnetic microbeads and several generations, mMSCs were of spindle, star and irregular shape. These cells were of rich cytoplasma, clear nucleolus, and grew in parallel or vortex. The cultured adherent cells from the first and subsequent generations had plenty of CD11b-positive blooding-making cells. After 20-day osteoblastic induction, mMSCs differentiated into bone cells, which showed orange phosphate in extracellular matrix by Alizarin red S staining. mMSCs could differentiate into lipocytes. The size of cells increased along with fat-developing induction period. These cells showed many orange fatty follicles with O Red Oil dyeing. Conclusion Pure mMSCs can not be retrieved by either adhering method or generation cultivation method separately. The combined methods of adhering, immunomagnetic microbeads, and serial subcultivation is effective in vitro in retrieve mMSCs.

AIM: To study influence of ischemia-reperfusion(IR) on apoptosis and expression of apoptosis-related genes Fas-L, Bax and Bcl-2 of sinoatrial node(SAN) cells in rabbits in vivo. METHODS:Ninety healthy adult rabbits were divided randomly into control group, ischemia groups (I 10 min , I 30 min , I 60 min and I 120 min ) and IR groups (I 10 min R 4h , I 30 min R 4h , I 60 min R 4h and I 120 min R 4h ). IR injury model of SAN was established by occluding and loosening the start section of right coronary artery. The apoptosis of SAN cells was detected by TUNEL staining. The expression of Fas-L, Bax and Bcl-2 of SAN cells was detected by immunohistochemistry. RESULTS:①No obvious apoptosis of SAN cells was observed in control group, I 10 min and I 30 min groups. Apoptosis of different degrees in SAN cells were found in 68.3%(41/60) rabbits in I 60 min , I 120 min and 4 subgroups of IR. ②The highest expression of Fas-L and Bax was observed in I 120 min group and that of Bcl-2 was in I 60 min group. ③The highest expression of Fas-L and Bax was observed in I 60 min R 4h group. The peak level of Bcl-2 was observed in I 30 min R 4h group. ④The expression of Fas-L and Bax was significant higher in IR group than that in ischemic group at the same time point. CONCLUSION:Ischemia and IR induced apoptosis of SAN cells in rabbit in vivo . Fas-L、Bax、Bcl-2 may participate in the regulation of apoptosis and the injury during IR aggravates the apoptosis of SAN cells.

Objective To study the effect of ischemia reperfusion(IR) on electrophysiological function of sinoatrial node(SAN) in rabbits. Methods Ninety healthy adult rabbits were divided randomly into control group, ischemia groups (I) 10(I10 min), 30(I30 min), 60(I60 min) and 120 min(I120 min) and IR groups (10, 30, 60 and 120 min ischemia followed by 4 h reperfusion respectively)(I10 minR4 h, I30 minR4 h, I60 minR4 h and I120 minR4 h). There were 10 rabbits in the control group and each subgroup. IR injury model of SAN was established by occluding and loosening the start section of right coronary artery(RCA). The changes of AA interval and arrhythmia were recorded by electrocardiography and cardiac chamber electrography synchronously. Results ① There was no significant difference in AA interval between different time points in the control group. ② Sinus arrest(SA), sinus bradycardia with arrhythmia(SB), or atrial tachyarrhythmia(AT) were found in 51 rabbits (63.75%) out of 80 rabbits in I and IR groups in ischemic period. The incidence rate of arrhythmia increased in a time dependent manner. The AA intervals also increased by at least 40 ms in 54 rabbits (67.5%). ③ Sinus or atrial arrhythmia during ischemic period was found in 26 out of the 40 rabbits in IR group, but 15 returned normal after reperfusion. ④ Increased AA intervals were found in 27 out of the 40 rabbits in IR group during ischemic period. Most of them recovered to pre occlusion level within 10 min after reperfusion, but the AA intervals prolonged again in I60 minR4 h and I120 minR4 h groups as the reperfusion elongated. Conclusion ① These findings suggest that about 2/3 of the rabbit sinus node arteries may stem from right coronary artery. ② Electrophysiological changes due to ischemia of SAN resemble the electrocardiogram of sick sinoatrial node syndrome. ③ Reperfusion arrhythmia can be induced by reperfusion after a long time of ischemia.