OBJECTIVETo investigate the role of AdeABC efflux pump in carbapenems resistance of Acinetobacter baumannii in light of the phenotype and genetype of the efflux pump.

METHODSThe phenotype of the efflux pump was detected in 138 clinical isolates of A.baumannii using the efflux pump inhibitor carbonyl cyanide 3-chlorophenylhydrazone (CCCP). The mRNA expression of pump-encoding gene adeB in the strains was detected using quantitative real-time RT-PCR.

RESULTSOf the 138 strains, 28 showed positivities for AdeABC efflux pump identified by Mueller-Hinton Broth with CCCP. Of the 39 strains resistant to meropenem, 15 (38.4%) showed positive results in CCCP assay, a rate significantly higher than that among the 99 sensitive strains (13.1%, 13/99) (X(2)=12.477(b), P=0.01). The mRNA expression of efflux pump-encoding gene adeB was detected by real-time RT-PCR at a level of 0.899∓∓1.172 in meropenem-sensitive strains, significantly lower than the level of 21.101∓∓21.443 in meropenem-resistant strains (t=4.403, P=0.000).

CONCLUSIONSEfflux plays a role in carbapenems resistance in the clinical isolates of A. baumannii. The AdeABC efflux pump may be an important factor in reducing carbapenems sensitivity in A. baumannii.

Acinetobacter baumannii ; drug effects ; isolation & purification ; Bacterial Proteins ; genetics ; metabolism ; Carbapenems ; pharmacology ; Humans ; Membrane Transport Proteins ; genetics ; metabolism ; beta-Lactam Resistance ; genetics

Objective To explore the application effect of new improved 3D printing individualized guidance(3D psi)in total knee arthroplasty(TKA)for knee osteoarthritis(KOA).Methods A total of 100 patients with KOA in 920th Hospital of Joint Logistics Support Force,PLA from January 2021 to January 2022 were selected,and were divided into 2 groups of 50 patients each using the randomized numerical table method.The control group was treated with conventional TKA,and the study group was treated with new improved 3D psi assisted TKA.The operation conditions,postoperative rehabilitation,complications,prosthesis component position deviation,knee range of motion(ROM),lower limb force line parameters[coronal distal femoral mechanical axis lateral angle(mldfa),lower limb mechanical axis angle(HKA)],gait parameters(percentage of support time,stride,pace),knee function(HSS score),quality of life(AIMS2 score)were observed.Results Com-pared with control group,the amount of intraoperative and postoperative blood loss and drainage volume 2 days after operation were less in the study group,and the operation time and hospital stay were shorter(P<0.05).The deviations of LTC Angle,FFC Angle,HKA Angle,LFC Angle and FTC Angle in the study group were smaller than those in the control group(P<0.05).At 3 months,6 months and 12 months after surgery,the percentage of knee ROM,supporting time,stride length and walking speed of the research group were higher than those of the control group,while the coronal-position mLDFA and HKA were lower than those of the control group(P<0.05).The proportion of WBC and PMN in joint fluid at 3 months,6 months and 12 months after surgery was lower than that in control group(P<0.05).The HSS score of the study group was higher than that of the control group at 3 months,6 months and 12 months after operation,and the AIMS2 score was lower than that of the control group(P<0.05).There was no statistically significant difference in the incidence of complications between the study group and the control group(P>0.05).Conclusion The new improved 3D PSI-assisted TKA treatment of KOA can optimize the surgical situation,improve operating accuracy,improve the patient's lower limb alignment,promote limb function recovery,help improve the quality of life,and has high safety.

OBJECTIVETo investigate the therapeutic effectiveness of intracoronary implantation of autologous bone marrow mononuclear cells (BM-MNC) in miniswine model of reperfused myocardial infarction.

METHODSSixteen miniswine myocardial ischemic reperfusion injury models made by ligation of the distal one third segment of left anterior descending artery for 90 minutes were randomized into 2 groups. In BM-MNC group (n = 9), (3.54 +/- 0.90) X 10(8) BM-MNC were intracoronary injected, and in the control group (n = 7), phosphate buffered saline was injected by the same way. Echocardiographic and hemodynamic results, vessel density, and myocardial infarction size were evaluated and compared before and 4 weeks after cell transplantation.

RESULTSIn BM-MNC group, there were no differences between before and 4 weeks after transplantation in aspects of left ventricular ejection fraction (LVEF), interventricular septal thickness, left ventricular lateral and anterior septal wall thickness, cardiac output, or +dp/dtmax. In control group, LVEF, interventricular septal thickness, left ventricular lateral and anterior septal wall thickness, cardiac output, and +dp/dtmax decreased significantly 4 weeks after transplantation (P < 0.05). Left ventricular end-diastolic pressure and -dp/dtmax, did not change significantly before and after cell transplantation in both groups. Capillary density in BM-MNC group was greater than that in control group [(13.39 +/- 6.96)/high power field vs. (3.50 +/- 1.90)/high power field, P < 0.05]. Infarction area assessed by tetrazolium red staining and the infarction percentage decreased in BM-MNC group compared with those in control group (P < 0.05).

CONCLUSIONSTransplantation of BM-MNC into myocardium with ischemic reperfusion injury increases capillary density and decreases infarction area. It has significantly beneficial effect on cardiac systolic function rather than on diastolic function.

Animals ; Bone Marrow Cells ; cytology ; physiology ; Bone Marrow Transplantation ; Capillaries ; physiology ; Echocardiography ; Heart ; anatomy & histology ; physiology ; physiopathology ; Hemodynamics ; Myocardial Ischemia ; Random Allocation ; Swine ; Systole ; physiology ; Transplantation, Autologous ; physiology

OBJECTIVETo investigate the therapeutic effectiveness of intracoronary transplantation of autologous bone marrow mononuclear cells (BM-MNC) on myocardial ischemia reperfusion injury in mini-swine model.

METHODSMyocardial ischemia reperfusion injury model was established by ligating in 16 mini-swines, which were further randomized into two groups: (3.54 +/- 0.90) x 10(8) BM-MNC was intracoronarily transplanted in BM-MNC group (n = 9), and phosphate buffer saline was intracoronarily applied in the control group (n = 7). Ultrasonic cardiograhpy, hemodynamics, neovascular density, and myocardium infarction size were evaluated before and 4 weeks after transplantation.

RESULTSIn BM-MNC group, left ventricular ejection fraction (LVEF), intra-ventricular septa, lateral wall and anterior wall, cardiac output (CO) and + dp/dt(max) had no significant differences before and 4 weeks after transplantation (P > 0.05). In the control group, LVEF, intraventricular septa, lateral wall and anterior wall, CO, and + dp/dt(max) significantly decreased 4 weeks after transplantation (P < 0.05). Left ventricular end-diastolic pressure and- dp/dt(max) had no significant differences before and after cell transplantation. Capillary density was significantly larger in the BM-MNC group than in the control group [(13.39 +/- 6.96) /HP vs. (3.50 +/- 1.90) /HP]. The percentage and size of myocardial infarction was significantly lower in the BM-MNC group than in the control group.

CONCLUSIONTransplantation of BM-MNC into the myocardial ischemic reperfusion-injury area can increase capillary density and decrease infarction area, and thus remarkably improve cardiac systolic function.

Animals ; Bone Marrow Transplantation ; Coronary Vessels ; Myocardial Reperfusion Injury ; pathology ; physiopathology ; therapy ; Myocardium ; pathology ; Random Allocation ; Swine ; Swine, Miniature

OBJECTIVETo simulate and assess the clinical effect of intracoronary infusion of bone marrow mononuclear cells or peripheral endothelial progenitor cells on myocardial reperfusion injury in mini-swine model.

METHODSTwenty-three mini-swine with myocardial reperfusion injury were used as designed in the study protocol. About (3.54 +/- 0.90) x 10(8) bone marrow mononuclear cells (MNC group, n = 9) or (1.16 +/- 1.07) x 10(7) endothelial progenitor cells (EPC group, n = 7) was infused into the affected coronary segment of the swine. The other mini-swine were infused with phosphate buffered saline as control (n = 7). Echocardiography and hemodynamic studies were performed before and 4 weeks after cell infusion. Myocardium infarction size was calculated. Stem cell differentiation was analyzed under a transmission electromicroscope.

RESULTSLeft ventricular ejection fraction dropped by 0% in EPC group, 2% in MNC group, and 10% in the control group 4 weeks after cell infusion, respectively (P < 0.05). The systolic parameters increased in MNC and EPC groups but decreased in the control group. However, the diastolic parameters demonstrated no significant change in the three groups (P > 0.05). EPC decreased total infarction size more than MNC did (1.60 +/- 0.26 cm2 vs. 3.71 +/- 1.38 cm2, P < 0.05). Undermature endothelial cells and myocytes were found under transmission electromicroscope.

CONCLUSIONSTransplantation of either MNC or EPC may be beneficial to cardiac systolic function, but might not has obvious effect on diastolic function. Intracoronary infusion of EPC might be better than MNC in controlling infarction size. Both MNC and EPC may stimulate angiogenesis, inhibit fibrogenesis, and differentiate into myocardial cells.

Animals ; Bone Marrow Cells ; cytology ; Bone Marrow Transplantation ; Cell Differentiation ; Endothelial Cells ; cytology ; Myocardial Reperfusion Injury ; pathology ; therapy ; Myocardium ; pathology ; Stem Cells ; cytology ; Swine ; Swine, Miniature

Objective: To verify the health advisory for short-term exposure to phenol. Methods: The method of this validation experiment was the same as the US Environmental Protection Agency (EPA) methodology for toxicology experiments used to determine phenol drinking water equivalent level (DWEL). Pregnant female Sprague-Dawley rats were administered phenol in distilled water by gavage at daily doses of 15, 30, 60, 120, and 240 mg/kg body weight (b.w.) from implantation (the 6th day post-mating) to the day prior to the scheduled caesarean section (the 20th day of pregnancy). The following information was recorded: general behavior; body weight; number of corpus luteum, live birth, fetus, stillbirth, and implantation; fetal gender; body weight; body length; tail length; and abnormalities and pathomorphological changes in the dams. Results: In the 60 mg/kg b.w. dose group, the mortality of pregnant rats increased with increasing doses, suggesting maternal toxicity. Fetal and placental weights decreased as phenol dose increased from 30 mg/kg b.w., and were significantly different compared those in the vehicle control group, which suggested developmental toxicity in the fetuses. However, the phenol-exposed groups showed no significant change in other parameters compared with the vehicle control group ( > 0.05). Conclusion Despite using the same method as the US EPA, a different NOEAL of 15 mg/(kg·d) was obtained in this study.
Animals ; Dose-Response Relationship, Drug ; Environmental Pollutants ; toxicity ; Female ; Fetal Development ; drug effects ; Phenol ; toxicity ; Pregnancy ; Rats ; Rats, Sprague-Dawley ; Toxicity Tests, Acute