Animals ; Cells, Cultured ; Gastrointestinal Tract ; metabolism ; Neuroglia ; metabolism ; Neurons ; metabolism ; Peptide Fragments ; metabolism ; Peptides ; metabolism ; Proteins ; metabolism ; Rats

OBJECTIVETo investigate the genotypic diversity of Methicillin-resistant Staphylococcus aureus (MRSA) isolated from pigs and retail foods from different geographical areas in China and further to study the routes and rates of transmission of this pathogen from animals to food.

METHODSSeventy-one MRSA isolates were obtained from pigs and retail foods and then characterized by multi-locus sequencing typing (MLST), spa typing, multiple-locus variable number of tandem repeat analysis (MLVA), pulsed-field gel electrophoresis (PFGE), and antimicrobial susceptibility testing.

RESULTSAll isolated MRSA exhibited multi-drug resistance (MDR). Greater diversity was found in food-associated MRSA (7 STs, 8 spa types, and 10 MLVA patterns) compared to pig-associated MRSA (3 STs, 1 spa type, and 6 MLVA patterns). PFGE patterns were more diverse for pig-associated MRSA than those of food-associated isolates (40 vs. 11 pulse types). Among the pig-associated isolates, CC9-ST9-t899-MC2236 was the most prevalent clone (96.4%), and CC9-ST9-t437-MC621 (20.0%) was the predominant clone among the food-associated isolates. The CC9-ST9 isolates showed significantly higher antimicrobial resistance than other clones. Interestingly, CC398-ST398-t034 clone was identified from both pig- and food-associated isolates. Of note, some community- and hospital-associated MRSA strains (t030, t172, t1244, and t4549) were also identified as food-associated isolates.

CONCLUSIONCC9-ST9-t899-MC2236-MDR was the most predominant clone in pigs, but significant genetic diversity was observed in food-associated MRSA. Our results demonstrate the great need for improved surveillance of MRSA in livestock and food and effective prevention strategies to limit MDR-MRSA infections in China.

Animals ; Anti-Bacterial Agents ; pharmacology ; China ; Food Microbiology ; Humans ; Methicillin ; pharmacology ; Methicillin Resistance ; Methicillin-Resistant Staphylococcus aureus ; genetics ; isolation & purification ; Nose ; microbiology ; Swine ; microbiology

Objective To evaluate the cardioprotection induced by ischemic preconditioning ( IPC) and hypoxic preconditioning ( HPC) which were carried out by using the double cardiopulmonary bypass ( CPB) circuits in in vivo hearts of dogs. Methods Eighteen healthy male dogs, weighing 17?5-24?5 kg, aged 13-24 months, were divided into 3 groups ( n=6 each) using a random number table: my?ocardial ischemia?reperfusion group (group I∕R), IPC group and HPC group. The double CPB circuits were established as follows: systemic and coronary circulation, and independent systemic and coronary cir?culation was carried out. In group IPC, the aorta was clamped, and the coronary circulation pump was sus?pended for 5 min followed by 5 min opening, repeating for 3 cycles. In group HPC, the aorta was clamped, the coronary circulation was started, and pure nitrogen was insufflated for 5 min followed by 5 min of oxygen insufflation, repeating for 3 cycles. CPB was performed for 1 h starting from the time point immediately after IPC or HPC. Before splitting of sternum ( T1 ) , after establishment of double CPB circuits ( T2 ) , at the end of preconditioning ( T3 ) , and at 60 and 120 min after restoration of spontaneous heart
beat ( T4,5 ) , heat rate, mean arterial pressure, central venous pressure, left ventricular end?systolic pres?sure, left ventricular end?diastolic pressure and the maximum rate of increase∕decrease of left ventricular pressure were recorded. Blood samples were collected from the right internal jugular vein at T1 and T4,5 for determination of serum cardiac troponin I concentrations. The animals were sacrificed after determination of the parameter or after blood sampling at T5 , myocardial specimens were obtained for examination of the ul?trastructure and for detection of apoptosis in cardiomyocytes, and apoptosis index was calculated. Before aortic clamping, immediately after aortic unclamping and at 30 min after aortic unclamping, myocardial specimens were obtained for determination of ATP contents in cardiomyocytes. Results Compared with I∕R group, left ventricular end?systolic pressure was significantly increased, and the serum cardiac troponin I concentrations were significantly decreased at T4,5 , the myocardial ATP contents were significantly in?creased immediately after aortic unclamping and at 30 min after aortic unclamping, apoptosis index was sig?nificantly decreased ( P<0?05 or 0?01) , and the pathological changes were significantly attenuated in IPC and HPC groups. Compared with group IPC, the myocardial ATP contents were significantly increased (P<0?05), and the pathological changes were attenuated in group HPC. Conclusion Both HPC and IPC can exert cardioprotection when carried out by using the double CPB circuits, and HPC provides better cardioprotection than IPC in in vivo hearts of dogs.

OBJECTIVETo study the diagnostic value and influencing factors for amplitude-integrated EEG (aEEG) in brain injury in preterm infants.

METHODSOne hundred and sixteen preterm infants with a gestational age (GA) between 27 weeks and 36(+6) weeks were enrolled as subjects. The aEEG scores of all preterm infants were obtained within 6 hours after birth. According to the diagnostic results, the 116 preterm infants were divided into two groups: brain injury (n=63) and non-brain injury (n=53). The risk factors for brain injury were evaluated using logistic regression analysis. According to the aEEG results, the 116 preterm infants were divided into two groups: normal aEEG (n=58) and abnormal aEEG (n=58). The influencing factors for aEEG results in preterm infants were determined using univariate analysis.

RESULTSThe brain injury group had a significantly higher rate of abnormal aEEG than the non-brain injury group (83% vs 11%; P<0.05). The infants in the brain injury group from two different GA subgroups (27-33(+6) weeks and 34-36(+6) weeks) had significantly lower aEEG scores than the non-brain injury group from corresponding GA subgroups (P<0.01). Logistic regression analysis showed that low GA (<32 weeks), low birth weight (<1 500 g), abnormal placenta, fetal membranes, and umbilical cord, and hypertension during pregnancy were high-risk factors for brain injury (P<0.05). There were significant differences in GA, birth weight, abnormal placenta, fetal membranes, and umbilical cord, and hypertension during pregnancy between the normal and abnormal aEEG groups (P<0.05).

CONCLUSIONSThe risk factors for brain injury are consistent with the influencing factors for aEEG results in preterm infants, suggesting that aEEG contributes to the early diagnosis of brain injury.

Birth Weight ; Brain Injuries ; diagnosis ; physiopathology ; Electroencephalography ; Female ; Humans ; Infant, Newborn ; Infant, Premature ; Logistic Models ; Pregnancy ; Risk Factors

OBJECTIVETo evaluate the value of serum procalcitonin (PCT) for the guidance of antibiotic therapy in children with lower respiratory tract infection (LRTI).

METHODSA prospective randomized controlled study was conducted in 396 children with LRTI who visited Weifang Maternity and Child Care Hospital. The participants were randomly assigned into a PCT group in which the antibiotic therapy was guided by serum PCT level and a control group in which the standard therapy was given according to clinical guidance. Afterwards, a subgroup analysis was performed according to whether the patient was diagnosed with community-acquired pneumonia (CAP). After 14-day treatment, antibiotic prescription rate, duration of antibiotic treatment, and side events were compared between the groups.

RESULTSA total of 396 cases were recruited and equally assigned into the PCT group and the control group, among whom the numbers of the children with CAP were 125 and 123, respectively. The mean duration of antibiotic treatment was significantly shorter in the PCT group than in the control group (P<0.05). The subgroup analysis showed that the duration of antibiotic treatment in both CAP and non-CAP PCT subgroups was significantly shorter than in the control subgroups (P<0.05), however, the antibiotic prescription rate in the non-CAP PCT subgroup was significantly higher than that in the non-CAP control subgroup (P<0.05). There were no differences in the rate and duration of side events from antibiotic therapy, hospitalization rate, the length of hospital stay, and safety between the PCT and control groups.

CONCLISOPNSSerum PCT-based guidelines on antibiotic use can shorten the duration of antibiotic therapy in children with LRTI.

Anti-Bacterial Agents ; therapeutic use ; Calcitonin ; blood ; Calcitonin Gene-Related Peptide ; Child, Preschool ; Community-Acquired Infections ; drug therapy ; Female ; Humans ; Infant ; Male ; Pneumonia ; drug therapy ; Prospective Studies ; Protein Precursors ; blood ; Respiratory Tract Infections ; blood ; drug therapy

Objective To study the influence of fluorine on signaling pathway of osteoprotegerin(OPG)/ receptor activator of NF-κB ligand(RANKL) in cultured rat osteoblasts.Methods Osteoblasts were isolated from skull of neonatal rats(＜ 24 hours) by enzyme digestion,and fluorine of different concentrations [0 (control),1 × 10-3,1 × 10-4,1 × 10-5,1 × l0-6 and 1 × 10-7 mol/L] were added into the culture medium of second generation of osteoblasts.The expressions of OPG and RANKL mRNA were determined using real-time PCR 24 and 48 hours after culturing.The expressions of OPG and RANKL protein were measured by Western blotting.Results ① After exposed to fluorine for 24 hours,the differences of RANKL and OPG mRNA expression had statistical significance between groups(F =30.95,22.62,all P ＜ 0.01),the expression of RANKL mRNA(5.99 ± 0.39) in the 1 × 10-5 mol/L group and the expressions of OPG mRNA(3.52 ± 0.09,4.81 ± 0.15,3.68 ± 0.04) in the 1 × 10-4,1 × 10-5 and 1 × 10-6 mol/L groups were higher than those of the control group(3.20 ± 0.19,3.09 ± 0.58,all P ＜ 0.05),but in the 1 × 10-3 mol/L group,RANKL mRNA(2.29 ± 0.18) was lower than that of the control group(P ＜ 0.05).After exposed to fluorine for 48 hours,the differences of RANKL and OPG mRNA expression had statistical significance between groups(F =26.62,5.72,all P ＜ 0.01),the expressions of RANKL and OPG mRNA(6.67 ± 0.49 and 5.05 ± 0.51) in the 1 × 10-5 mol/L group were higher than those of the control group(4.29 ± 0.07 and 4.34 ± 0.12,all P ＜ 0.05),and in the 1 × 10-3 mol/L group the expression of OPG mRNA(3.63 ± 0.49) was lower than that of the control group(P ＜ 0.05).② The expression of RANKL protein was not statistically significant between 24 hours and 48 hours groups (F =0.07,0.49,all P ＞ 0.05) ; the differences of OPG protein expression had statistical significance between groups(F =3.26,P ＜ 0.05),the expression of OPG protein in the 1 × 10-5 mol/L group(1.45 ± 0.10) was higher than that of the control group(1.05 ± 0.06,P ＜ 0.05) at the 24 hours.After 48 hours,the expression of OPG protein was not statistically significant(F =0.44,P ＞ 0.05).Conclusions At lower fluorine concentrations,bone formation is the main activity.But when fluorine concentration increased and time prolonged,the osteoclast differentiation and maturation are promoted,and the bone resorption is the main thing.

OBJECTIVETo study the effects of umbilical cord blood monocytes (UCBMC) transplantation on erythropoietin (EPO) protein and oligodendrocyte progenitor cells in hypoxia-ischemia (HI) neonatal rats.

METHODSForty seven-day-old Sprague-Dawley rats were randomly divided into normal control (N), HI, UCBMC and HI+UCBMC groups (n=10 each). Hypoxic-ischemic brain damage (HIBD) model was prepared according to the Rice method. Twenty-four hours after hypoxia, the N and HI groups were injected with 2 μL phosphate buffered saline (PBS), and the UCBMC and HI+UCBMC groups were injected with 3×10(6) UCBMC via the lateral ventricle. EPO protein and oligodendrocyte progenitor cells in the subventricular zone of the injured brain were observed by EPO/DAPI and NG2/DAPI immunofluorescence double staining, and their correlation was analyzed.

RESULTSSeven days after transplantation, there were more NG2(+)DAPI(+) and EPO(+)DAPI(+) cells in the HI+UCBMC group than in the UCBMC (P<0.05), N and HI groups (P<0.01). More NG2(+)DAPI(+) and EPO(+)DAPI(+) cells were observed in the UCBMC group compared with the N and HI groups (P<0.01). There were more NG2(+)DAPI(+) cells in the N group than in the HI group (P<0.01). The number of NG2(+)DAPI(+) cells was correlated with the number of EPO(+)DAPI(+) cells in the HI+UCBMC group (r=0.898, β=1.4604, P<0.01).

CONCLUSIONSUCBMC can promote expression of oligodendrocyte progenitor cells, which is correlated with an increase in EPO protein and thus repairs brain white matter damage in neonatal rats with HIBD.

Animals ; Animals, Newborn ; Erythropoietin ; analysis ; biosynthesis ; Fetal Blood ; cytology ; Hypoxia-Ischemia, Brain ; metabolism ; pathology ; therapy ; Monocytes ; transplantation ; Oligodendroglia ; pathology ; Rats ; Rats, Sprague-Dawley ; Stem Cells ; pathology

OBJECTIVETo investigate the effects of endothelia progenitor cells conditioned medium (EPC-CM) on the migration, adhesion and proliferation of vascular smooth muscle cells (VSMCs).

METHODSMononuclear cells were isolated from rat bone marrow by density gradient centrifugation,plated on dishes precoated with 5% fibronectin, and then cultured with complete M199 medium (including 15% fetal calf serum, 10 microg/L VEGF and 5 microg/L bFGF). EPC-CM was collected and used to incubate VSMCs isolated from rat arteriae aorta. After 24 h, VSMCs proliferation, adhesion and migration were assayed with CCK-8, adhesion test and modified Boyden chamber assay, respectively.

RESULTSThe proliferation, adhesion and migration of VSMCs were obviously decreased when the cells were cultured with EPC-CM.

CONCLUSIONEPC-CM could inhibit VSMC functions, which would be one of the mechanisms against atherosclerosis by EPCs.

Animals ; Cell Adhesion ; Cell Movement ; Cell Proliferation ; Cells, Cultured ; Culture Media, Conditioned ; chemistry ; Endothelial Cells ; cytology ; Male ; Muscle, Smooth, Vascular ; cytology ; Rats ; Rats, Sprague-Dawley ; Stem Cells ; cytology

The present study was designed to investigate the effects of various extracellular matrix (ECM) proteins on the biological characteristics of late endothelial progenitor cells (EPCs). Density gradient centrifugation-isolated rat bone marrow mononuclear cells were cultured in complete M199 medium, which contained 15% fetal calf serum, 10 μg/L vascular endothelial growth factor (VEGF) and 5 μg/L basic fibroblast growth factor (bFGF). EPCs were plated on substrates containing fibronectin (Fn), laminin (Ln) or rat tail tendon collagen (Col), and the corresponding cells were defined as Fn, Ln and Col groups. The 3rd generation EPCs, namely late EPCs, were harvested. The proliferation, adhesion, migration and the ability of forming tubes were assayed using CCK-8, adhesion test, wound healing assay and Matrigel, respectively. The mRNA expressions of endothelial cell differentiation markers, vWF and CD31, were analyzed by real time RT-PCR. The apoptosis was assayed by flow cytometry (FCM). The results showed that cell proliferation ability of Fn and Col groups were higher than that of Ln group; Fn group showed increased adhesion compared to Col and Ln groups (P < 0.01); The migration ability of Fn and Col groups were higher than that of Ln group. Moreover, Fn group showed increased tube formation abilities compared to Col and Ln groups (P < 0.05). Although 24-hour free-serum-induced apoptosis in Ln group was the highest, there was no difference of auto-apoptosis among the three groups. Furthermore, the mRNA expressions of vWF and CD31 exhibited no difference among the three groups. These results suggest the ECM affects the biological functions of late EPCs, which would have a high probability of providing new directions that lead to the development of artificial heart and blood vessels.
Animals ; Cell Proliferation ; Cells, Cultured ; Collagen ; chemistry ; Endothelial Progenitor Cells ; cytology ; Extracellular Matrix ; physiology ; Extracellular Matrix Proteins ; chemistry ; Fibroblast Growth Factor 2 ; chemistry ; Fibronectins ; chemistry ; Rats ; Vascular Endothelial Growth Factor A ; chemistry

ObjectiveTo investigate the morphologic features of coronary sinus (CS)-left atrium muscle connections,and evaluate the function and anatomical features of coronary sinus on dual-source CT coronary angiography (DSCTCA).MethodsImages of DSCTCA of 144 patients [ control group consisted of 96 patients,and atrial fibrillation (AF) group consisted of 48 patients] were reviewed.The existence of coronary sinus-right atrium muscle connections was indirectly evaluated by measuring the cross-sectional area changes of the CS during atrial systole and atrial diastolic.The number,location,length of the CS-left atrium muscle connections andthe relationship between CS-left atrium muscle connections and CS morphological characteristics were studied.The t test for continuous variables and Chi-square test for categorical variables were used in statistical analysis.Results( 1 )The anatomic course of the CS in relation to the mitral ring was straight,mild curvature and high riding of 62,16 and 18 cases in control group and 10,8 and 30 cases in AF group,respectively.There was not statistical significance between the 2 group (x2 =0.093,P=0.954). (2)The CS length was (34.1 ±9.1),(33.8 ±8.9)mm in Control group and AF group,respectively.There was no statistical significance between the 2 group ( t =- 0.486,P =0.628 ).(3) Coronary sinus-left atrium muscle connections were seen in 131 of the 144 patients (91.0％).A single connection was seen in 103 of the 144 patients,with a mean length of (22.6 ± 12.7)mm within (6.3 ± 5.8 ) mm of the coronary sinus ostium.28 patients had two connections; distal connections measured ( 13.2 ± 6.2)mm in length within (16.7 ± 6.8 ) mm of the coronary sinus ostium,and proximal connections measured ( 11.1 ± 3.6 ) mm in length within (2.1 ± 1.9) mm of the coronary sinus ostium.And there was no statistical difference the number and length of CS-left atrium connections in between Control group and AF group (P ＞ 0.05 ).(4)The CS narrowed 22.4％ (44.5/198.8 )in cross-sectional area from atrial diastolic to atrial systole in control group( t =- 21.076,P ＜ 0.01 ),while the CS had no obvious contraction in AF group(t =0.374,P ＞ 0.05).The cross-sectional area of the coronary sinus during diastole was obviously larger in the AF group than in the control group[( 230.4 ±77.0) mm2 vs (198.8 ±65.4) mm2,respectively,t =- 2.579,P =0.01 ].In control group ( n =9 ),the coronary sinus-left atrium connection was not seen,however,all showed a CS constriction during atrial systole,indicating that coronary sinus-left atrium muscle continuity is not likely the primary cause for coronary sinus contractions. Conclusions DSCTCA can clearly show the anatomical characteristics of CS,it can help to understand the length,number and location of the CS-left atrium muscle connection.