In order to establish a method by which the recombinant suicide plasmids integrated on the chromosome could be recircled, A simple method of transconjugative cloning was established with the helper plasmids pMT999 or pRK2013 and fusion strains of Shigella flexneri which were obtained by screening with in vivo expression technology. And the cloning efficiency with this method is very high.

BACKGROUNDAdvances in catheter ablation procedures for the treatment of supraventricular arrhythmias have created the need to understand better the morphological and electrophysiological characteristics of the inferior nodal extension (INE) and transitional cellular band (TCB) in the atrioventricular (AV) junctional area.

METHODSFirstly, we observed the histological features of 10 rabbit AV junctional areas by serial sections under light microscopy. Then we recorded the action potentials (APs) of transitional cells (TCs) in the INE, TCBs, AV node, and ordinary right atrial myocytes from the AV junctional area of 30 rabbits using standard intracellular microeletrode techniques.

RESULTSUnder light microscopy, the INE appeared to be mostly composed of transitional cells linking upward to the AV node. Four smaller TCBs originated in the orifice of the coronary sinus, the region between the septal leaflet of the tricuspid valve and the coronary sinus, the inferior wall of the left atrium, and the superior interatrial septum, respectively, all linking to the INE or the AV node. Compared with ordinary atrial myocytes, the AP of the TCs in both the INE and the TCBs had a spontaneous phase 4 depolarization (not present in ordinary atrial myocytes), with a less negative maximum diastolic potential, a smaller amplitude, a slower maximum velocity of AP upstroke, and a longer action potential duration at 50% repolarization (APD50) and at 30% repolarization (APD30). The AP characteristics of these TCs were similar to those of the AV node, except that the velocities of the phase 4 spontaneous depolarization were slower and their action potential durations at 90% repolarization (APD90) were shorter. Moreover, APD50 and APD30 of the TCs of the TCBs were shorter than in the case of TCs of the AV node.

CONCLUSIONSThe TCs of the INE and TCBs are similar to slow response automatic cells. They provide a substrate for slow pathway conduction. In addition, repolarization heterogeneity exists in the AV junctional area.

Action Potentials ; Animals ; Atrioventricular Node ; cytology ; physiology ; Female ; Male ; Rabbits

It is generally accepted that the inhibition of apoptosis is one of the mechanism of drug resistance to tumor. Members of the bcl-2 gene family are the most important regulators in apoptosis. The purpose of this study is to evaluate the value of expression of bcl-2 and bax gene in predicting the prognosis of acute leukemia patients, and to explore the relationship between bcl-2 and bax expression and drug resistance. Seventy patients with acute leukemia entered this study. Expressions of bcl-2, bax and mdr-1 gene were measured by RT-PCR method and FCM. The result showed that: bcl-2 had been widely detected in specimens of blood or bone marrow from acute leukemia patients, the expression levels were much higher than those in normal control (1.46 vs 0.71, P < 0.05), bax expression levels and bax/bcl-2 ratio in patients had no significant difference with the control. No relationships were found between the expression levels of bcl-2 and bax and AL patients' age, sex, platelet counts, hemoglobin levels, percentage of marrow blasts, FAB classification, and S + G(2)M%. Both Bcl-2 protein expression (34.6% vs 69.2%, P < 0.03) and bax/bcl-2 mRNA ratio (37.1% vs 82.9%, P < 0.01) were associated with response to therapy and CR rate, bax/bcl-2 ratio also influences the overall survival time. There was no relationship between bcl-2 and bax expression levels and mdr-1 expression levels.

OBJECTIVE: To determine the relationship between bone alkaline phosphatase (BAP) and cross-linked N-telopeptides of type I collegen(NTX) and bone mineral density in healthy men aged 20-80. METHODS: BAP and NTX of 389 healthy men were measured by ELISA. BMD at the lumbar spine and the hip as measured by dual energy X-ray absorptiometry. The correlation of bone biochemical markers with age and BMD fit 10 regression models. RESULTS: BAP and NTX negatively correlated with age. The cubic regression model was better with age-related changes of bone biochemical markers as compared with the other regression models and the coefficients of determination of fitting curve were 0.013-0.029 (P< 0.05). The value of bone biochemical markers as the highest during 20-29 age groups, then they decreased to a nadir level in the 50-59 years age. After 60 years, bone formation markers remained stable; however resorption marker increased slightly. After adjustment for age, weight, height, BMI, and smoking, bone biochemical markers were negatively correlated with most sites of BMD. CONCLUSION BAP and NTX may be relatively sensitive and specific markers to evaluate age-related changes of bone turnover. It may benefit the prevention of osteoporosis by monitoring the level of BAP and NTX.
Adult ; Age Factors ; Aged ; Aged, 80 and over ; Alkaline Phosphatase ; metabolism ; Biomarkers ; Bone Density ; Bone and Bones ; metabolism ; Collagen Type I ; metabolism ; Humans ; Male ; Middle Aged ; Osteoporosis ; prevention & control ; Peptides ; metabolism

Objective To observe the effects of genistein and 17?-estradiol on microstructure of cancellous bone in ovariectomized (OVX) rats.Methods Ninty 7-month-old SD rats were randomly divided into baseline group,ovariectomized (OVX),sham-operated (SHAM),17?-estradiol treated (10?g?kg~(-1).day~(-1),EST) and genistein treated (5 mg?kg~(-1)?day~(-1),GEN) groups,and were killed at the beginning of the experiment,the 3rd and 15th week after operation.MicroCT scanning was performed on the left tibia in vitro.The regions involving 0.5 mm slice thickness and 1.6 mm distal to the tibial growth plate were selected as the regions of interest.Results At the 3rd week after operation,the tissue bone mineral density (tBMD) and trabecular thickness (sTh.Th) in group GEN were significantly higher than those in OVX and EST groups (all P

OBJECTIVEThis study was aimed to observe the efficacy of autologous stem cell transplantation (ASCT) for adult patients with acute lymphoblastic leukemia (ALL), and investigate related prognostic factors.

METHODSA total of 86 adult ALL patients underwent ASCT in Institute of Hematology and Blood Disease Hospital from November 2001 to January 2012 were followed up. Clinical characteristics and outcomes of all patients were retrospectively analyzed. Survival and univariate prognosis were analyzed by the Kaplan-Meier method and multivariate analysis by COX regression model.

RESULTSOutcomes were assessed in 81 cases, including 47 standard-risk and 34 high-risk patients. 1-, 3-, 5-, and 10-year leukemia-free survival (LFS) of standard-risk patients were (82.3±5.7)%, (76.9±6.5)%, (74.1±6.8)%, (67.4±8.9)% respectively,and relapse rates (RR) were as of (13.6±5.2)%, (21.6±6.4)%, (24.5±6.8)%, (31.3±9.0)% respectively. 1-, 3-, 5-, and 10-year LFS of high-risk patients were (55.8±8.9)%, (39.8±9.3)%, (39.8±9.3)%, (39.8±9.3)% respectively, and relapse rates (RR) were (38.8±9.2)%, (56.4±10.0)%, (56.4±10.0)%, (56.4±10.0)% respectively. T-ALL, white blood cell count(WBC) more than 30×109/L when first visited, increased LDH, positive fusion gene of TCR and bone marrow transplantation were the adverse prognostic factors. Multivariate analysis showed bone marrow transplantation was an independent adverse prognostic factor.

CONCLUSIONASCT was a choice for adult ALL patients when suitable donors were unavailable.

Adolescent ; Adult ; Female ; Follow-Up Studies ; Hematopoietic Stem Cell Transplantation ; Humans ; Male ; Middle Aged ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; therapy ; Prognosis ; Retrospective Studies ; Risk Factors ; Transplantation, Autologous ; Young Adult

OBJECTIVETo evaluate the outcome of allogeneic hematopoietic stem cell transplantation (allo-HSCT) from HLA-matched sibling donor (MSD allo-HSCT) for severe aplastic anemia (SAA).

METHODSThe clinical data of 41 SAA patients received MSD allo-HSCT from May. 2003 to Aug. 2011 were analyzed retrospectively. 24 patients were male, 17 were female. Median age was 23 (5 - 43) years old. 28 patients had SAA-I, 9 had SAA-II, and 4 had post-hepatitis aplastic anemia. 17 patients received allogeneic bone marrow (BM) transplantation (allo-BMT), and 24 received allogeneic peripheral blood stem cell (PBSC) transplantation (allo-PBSCT). The conditioning regimens: 20 patients received cyclophosphamide (CY) + anti-thymocyte globulin (ATG) + fludarabine (Flu), 21 received CY + ATG + Flu+ cytarabine (Ara-C) ± busulfan (Bu)/melphalan (Mel). Prophylaxis for graft-versus-host disease (GVHD): 25 patients received cyclosporine (CSA) plus short-term methotrexate (MTX), 16 received tacrolimus (FK506) plus short-term MTX. The median number of infused CD34(+) cells were 3.48 (2.39 - 4.80)×10(6)/kg in allo-BMT and 2.95 (1.27 - 5.98)×10(6)/kg in allo-PBSCT, respectively.

RESULTSHematopoietic reconstitution was observed in all 41 patients (100%). The median time of neutrophils (ANC) reached to 0.5×10(9)/L and platelets (PLT) reached to 20×10(9)/L were 14 (10 - 23) days and 19 (8 - 38) days, respectively. 12 patients developed acute GVHD (aGVHD), out of which 11 developed grade I-II aGVHD, and one developed grade IV. 2 patients occurred chronic GVHD (cGVHD), out of which one with local cGVHD and the other with extensive. 4 patients occurred graft rejection (GR), all of them recovered haemopoiesis and survived after donor PBSC infusion. 5 patients (12.2%) died, out of which one died of extensive cGVHD, and 4 died of invasive fungal infections (IFI). Median follow-up time was 23 (3 - 79) months. 36 patients survived. 5-year estimated overall survival (OS), disease free survival (DFS), and transplant-related mortality (TRM) was (81.1 ± 9.0)%, (68.4 ± 11.0)%, and (18.9 ± 9.0)%, respectively. Univariate analysis showed that lover OS had significant correlation with receiving PBSCT, occurrence of aGVHD, the number of infused CD34(+) cells no more than 2.5×10(6)/kg, the number of red blood cell (RBC) transfusion before transplant more than 30 U and occurrence of IFI after transplantation (P = 0.034, 0.001, 0.006, 0.000, 0.001, respectively). Occurrence of aGVHD had significant correlation with the disparity between donor and recipient ABO blood groups, the number of PLT transfusion more than 100 U, and the number of RBC transfusion more than 30 U before transplantation, the number of infused CD34(+) cells no more than 2.5× 10(6)/kg (P = 0.019, 0.038, 0.005, 0.005, respectively). The occurrence of GR had significant correlation with the number of PLT transfusion more than 100 U before transplantation (P = 0.038).

CONCLUSIONMSD allo-HSCT is an effective therapy for patients with SAA. Lower number of blood transfusion before transplantation, use of BMT, more number of infused CD34(+) cells can effectively prevent and treat aGVHD and IFI after transplantation, which may improve the efficacy of MSD allo-HSCT for SAA.

Adolescent ; Adult ; Anemia, Aplastic ; therapy ; Child ; Child, Preschool ; Female ; HLA Antigens ; Hematopoietic Stem Cell Transplantation ; Humans ; Male ; Retrospective Studies ; Siblings ; Tissue Donors ; Treatment Outcome ; Young Adult

Shigella flexneri is an infectious pathogen that causes dysentery to human, which remains a serious threat to public health, particularly in developing countries. In this study, the global protein expression patterns of S. flexneri during transition from exponential growth to stationary phase in vitro were analyzed by using 2-D PAGE combined with MALDI-TOF MS. In a time-course experiment with five time points, the relative abundance of 49 protein spots varied significantly. Interestingly, a putative outer membrane protein YciD (OmpW) was almost not detected in the exponential growth phase but became one of the most abundant proteins in the whole stationary-phase proteome. Some proteins regulated by the global regulator FNR were also significantly induced (such as AnsB, AspA, FrdAB, and KatG) or repressed (such as AceEF, OmpX, SodA, and SucAB) during the growth phase transition. These proteins may be the key effectors of the bacterial cell cycle or play important roles in the cellular maintenance and stress responses. Our expression profile data provide valuable information for the study of bacterial physiology and form the basis for future proteomic analyses of this pathogen.
Bacterial Proteins ; analysis ; Computational Biology ; Electrophoresis, Gel, Two-Dimensional ; Gene Expression Profiling ; methods ; Kinetics ; Peptide Mapping ; Proteome ; analysis ; Proteomics ; methods ; Shigella flexneri ; growth & development ; metabolism ; pathogenicity ; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization ; Temperature ; Trypsin ; pharmacology ; Virulence

OBJECTIVETo constitute the animal model of unilateral olfactory nerve transection and observe the expression level and distribution of odorant receptors.

METHODSThirty-two rats were divided into two groups: the olfactory nerve transection group (20) and the control group (12). The former group received the operation to transect the left olfactory nerve following the left olfactory bulb was exposed under microscope and the latter group did not give any disposal. At every stage of five days, two weeks, four weeks and six weeks after the operation, five rats from the nerve transection group and three from the control group were anaesthetized simultaneously, and olfactory epithelium were taken out after transcardial perfusion, then paraffin imbedding. Coronal sections were sliced for HE staining to observe the thickness changes of the olfactory epithelium, and for in situ hybridization (ISHs) to investigate the expression of olfactory receptor genes (Olr287, Olr226, Olr1493 and Olr1654) in the epithelium, also to evaluate the changes of the expression level and location of the selected receptors during the regeneration of olfactory epithelium.

RESULTSHE staining showed that 5 days after the operation cell quantity and thickness of the olfactory epithelium decreased obviously, which increased gradually 2 or 4 weeks after operation. After 6 weeks' recovery, the thickness of the epithelium could reach the control level. The pattern of cell staining by ISH showed a specific spatial distribution along the anteroposterior (AP) and dorsoventral (DV) axis. Evidence suggested that odorant receptors were distributed in continuous and multiple overlapping bands in the normal or nerve transected-recovered epithelium rather than in the conventionally accepted three or four zones. The data also demonstrated that the distribution of sensory neuron types, as identified and defined by odorant receptor expression, was restored to normal or nearly so by 6 weeks after operation. Likewise, the numbers of probe-labeled neurons in the nerve transected-recovered had an obvious decrease 5 days after olfactory nerve transection. Reactive cells (x(-) +/- s) of Olr1493 in the operated side was (53.9 +/- 19.9), compared with (419.0 +/- 21.2) in the unoperated side, there was statistic significance between them (t = 63.960, P < 0.01). Reactive cells increased gradually according to the regeneration of the epithelium, and were nearly equivalent to the normal side 6 weeks later without significant differentiation (t = 2.600, P > 0.05), according to the absolute positive cells in the operated and unoperated side of (417.8 +/- 32.4) and (445.3 +/- 10.0) respectively.

CONCLUSIONThe regeneration of the sensory neurons and receptors, both the number and the distribution, can recover to normal after olfactory nerve transection.

Animals ; Male ; Olfactory Mucosa ; metabolism ; Olfactory Nerve ; metabolism ; surgery ; Olfactory Nerve Injuries ; Olfactory Receptor Neurons ; cytology ; metabolism ; Rats ; Rats, Sprague-Dawley ; Receptors, Odorant ; genetics ; metabolism