Molecular Characterization of Enterotoxigenic Escherichia coli in Foodborne Outbreak

Diarrheagenic Escherichia coli (E. coli) is a main cause of diarrhea worldwide. This study reports the investigation on the occurrence of enterotoxigenic E. coli (ETEC) serotype O27:H7-associated foodborne gastrointestinal disease that occurred at two schools, one middle school and one high school, in Seoul, Korea in June 2015. The immediate government investigation in 1,216 students and 19 food handlers in these two schools revealed that 116 students, 32 students in the middle school and 84 students in the high school, and 2 food handlers, one from middle school and the other from high school, developed gastrointestinal illness symptoms including diarrhea. Following lab investigation identified 29 ETEC serotype O27:H7 strains, 27 from 116 students and 2 from 19 food handlers. Pattern of pulsed-field gel electrophoresis analysis of ETEC isolates suggested that ETEC serotype O27:H7 caused the diarrheal outbreak in June 2015 in Seoul, Korea was a specific clone. In addition, these ETEC serotype O27:H7 isolates were highly resistance to the several antibiotics. The results from the present study provide the evidence that ETEC serotype O27:H7 can be an important cause of domestic foodborne outbreak in Korea.

Analysis of noninvasive hemodynamics in patients with cardiac disfunction during different periods / 军事医学

Objective To observe the changes in noninvasive hemodynamic parameters in patients with chronic heart failure (CHF) at different stages of development,and to explore the clinical significance of related parameters.Methods A total of 119 patients who had been hospitalized in the Heart Center of our hospital between March 2014 and Orctober 2016 were divided into phases A,B,and C according to the ACC/AHA Progression Criteria for Chronic Heart failure.Phase A was pre heart failure group A,phase B was pre clinical heart failure stage group B,and phase C was the clinical stage of heart failure group C.Meanwhile,39 healthy people in our hospital were chosen as group O.Their clinical data,serum BNP levels and LVEF values were collected,the noninvasive hemodynamic indexes of heart function were recorded by the noninvasive cardiac function detection system,including stroke volume (SV),cardiac output (CO),cardiac index (CI),systolic C wave amplitude,cardiac contractility index (HI),systolic function of heart contractility index (Q-B/B-X),pulmonary artery wedge pressure (PCWP),left ventricular end diastolic pressure (LVEDP),aortic compliance (AC) and total peripheral resistance (TPR).Comparative analysis of noninvasive hemodynamic indexes and changes in BNP and LVEF in different stages of CHF was conducted.Results The levels of C,SV,CO,CI,AC and HI in groups A,B and C were lower than those in control group (P ＜0.05),while Q-B/B-X,PCWP,LVEDP,and TPR were higher than those in the control group (P ＜ 0.05).C,CI,and HI decreased more significantly,but Q-B/B-X,PCWP,and LVEDP increased with the development of heart failure (P ＜ 0.05).BNP was significantly higher in group C than in normal control group (P ＜ 0.05),but there was no significant difference between group A and B.LVEF in group C was significantly lower than that in group O (P ＜ 0.05).There were negative correlations between SV,CO,CI,C,HI,AC and LVEF at different stages of heart failure,but there were positive correlations between Q-B/B-B,PCWP,LVEDP,TPR,and BNP.Receiver operating characteristics curve analysis further indicated the value of the noninvasive hemodynamic parameters C,CI,HI and Q-B/B-X in evaluation of cardiac function in the early stage of heart failure.Conclusion The changes in noninvasive hemodynamic parameters are consistent with the different stages of heart failure,which can provide an objective reference for early evaluation of cardiac function.

Surgical treatment of severe scoliosis and kyphoscoliosis by stages / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Although previous reports had reported the use of temporary internal distraction as an aid to correct severe scoliosis, two-stage surgery strategy (less invasive internal distraction followed by posterior correction and instrumentation) has never been reported in the treatment of patients with severe spinal deformity. This study aimed to report the results of the surgical treatment of severe scoliosis and kyphoscoliosis by two-stage and analyse the safety and efficacy of this surgical strategy in the treatment of severe spinal deformities.</p><p><b>METHODS</b>A total of 15 patients with severe scoliosis, kyphoscoliosis or kyphosis who underwent two-stage surgeries (less invasive internal distraction followed by posterior correction and instrumentation) were studied based on hospital records. Pretreatment radiographs and radiographs taken after first surgery (internal distraction by two small incisions), before second surgery (posterior correction, instrumentation and fusion), one week after second surgery and final follow-up were measured. Subjects were analyzed by age, gender, major coronal curve magnitude, flexibility of major curve, major sagittal curve magnitude before first surgery, after first surgery, before second surgery, after second surgery and at final follow-up. Complications related to two-stage surgeries were noted in each case.</p><p><b>RESULTS</b>The average major curve magnitude was 129.4° (range, 95° to 175°), reduced 58.9° or 45.4% after first stage surgery and reduced 30.6° or 24.6% after second stage surgery. The loss of correction during the interval between two surgeries was 7.1%. The total major coronal curve correction was 81.4° or 62.9%. At the final follow up, the average loss of correction of major coronal curve was 3.9° and the final average correction rate was 59.7%. The average major sagittal curve magnitude was 80.3° (range, 30° to 170°), and the total major sagittal curve correction was 48.2°. Loss of correction averaged 4.0° for major sagittal curve and the final correction averaged 42.2°. Clinical complications were noted in the peri-operative and long-term periods.</p><p><b>CONCLUSIONS</b>Two-stage surgery was a safe and effective surgical strategy in this difficult population. Using two-small-incision technique, the first stage surgery was less invasive. No permanent neurologic deficit was noted in this series.</p>

Analysis of neurological deficits complications in the treatment of spinal deformity with posterior spinal osteotomy / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the incidence and causes of neurologic deficits complications in the treatment of spinal deformity with posterior spinal osteotomy.</p><p><b>METHODS</b>From January 2007 to December 2010, 321 cases of scoliosis or kyphosis patients were treated with posterior spinal osteotomy. There were 124 male and 197 female with an average age of (19 ± 11) years (2 - 56 years). The average preoperative main Cobb angle was 108° ± 33° (48° - 175°), the average kyphotic angle was 74° ± 29° (53° - 170°) before operation. Pedicle subtraction osteotomy was used in 226 cases, 95 cases with vertebral column resection. Pedicle screw-rod system was used for fixation. The patients were monitored by Somatosensory-evoked potentials monitoring and Stagnara wake-up test.</p><p><b>RESULTS</b>There were 11 cases with varying degrees of new neurologic deficits and the total incidence was 3.4%. The causes were as followed, spinal translation in 2 cases, compromised by close of resected areas in 2 cases, residual bone compression in 1 case, inadvertent operation in 2 cases, screw malposition in 1 case, hematoma compression in 1 case and spine elongation in 2 cases. There was significant difference between the patients with preexisting neurologic deficits (20.0%) and the patients with intact neurologic function (2.6%) (χ(2) = 13.060, P = 0.011), no significant differences in different classes of the age, etiology, deformity, osteotomy type and surgical type (P > 0.05). But the incidence of neurologic deficits was 4.6% in congenital scoliosis, 7.1% in neuromuscular scoliosis, 5.1% in kyphosis, 5.9% in adult deformity and 5.9% in Cobb angle more than 100°, which was higher than other classes. All the 11 cases were given emergent Methylprednisolone, neurotrophic drugs and hyperbaric oxygen therapy, 4 cases were underwent surgical exploration again. After treatment, 7 cases recovered completely, 2 cases recovered partially and 2 cases failed to improve at the last follow-up.</p><p><b>CONCLUSIONS</b>Severe spinal deformity could be effectively treated with posterior spinal osteotomy. But the procedure is technical demanding and risky for neurologic deficits. The high risk factor is preexisting neurologic deficits.</p>

Balloon inflating and cement filling for treatment of avascular necrosis of the femoral head: a three-dimensional infinite-element study / 南方医科大学学报

<p><b>OBJECTIVE</b>To evaluate the biomechanical changes of balloon inflating and cement filling in avascular necrosis of the femoral head using finite-element analysis.</p><p><b>METHODS</b>The procedure of percutaneous balloon inflating and cement filling was simulated in fresh specimen of human femoral head. CT scan and three-dimensional reconstruction were used to establish the three-dimensional model of the femoral head. The physiological load was analyzed using three-dimensional finite element model to simulate the load and calculate stress on the hip during walking. Finite element analysis was performed on the avascular necrosis model and balloon inflating and bone cement filling model to measure the Von-Mises force at the top, neck and weight-bearing area of the femoral head. Another 8 fresh specimens of femoral head necrosis of human were obtained to stimulate balloon inflating and bone cement filling procedures, and the displacement of the femoral head under different loads was recorded before and after the procedures.</p><p><b>RESULTS</b>After bone cement filling in the necrosis area, the load reduced significantly in the weight-bearing area of the femoral head, and the load distribution became more uniform at the femoral neck and the top of the head. The anti-deformation ability of the necrosis femoral head increased after bone cement filling. The infinite-element analysis and specimen biomedical test showed similar results.</p><p><b>CONCLUSION</b>Percutaneous balloon inflating and bone cement filling in the necrosis area can change the biomechanics mechanism of the femoral head and neck, improve the supporting capacity under load, and prevent the progression of head collapse.</p>

Clinical application of posterior paramedian approach in low back surgeries / 中华外科杂志

<p><b>OBJECTIVE</b>To prospectively evaluate the clinical effects of posterior paramedian approach in nerve root decompression and reducing muscle damage in low back surgeries.</p><p><b>METHODS</b>Study group included 30 cases treated from January 2007 to May 2008, DDD 8 cases, spondylolisthesis 6 cases, LDH 11 cases, Low back surgery failure re-operation 5 cases. Based on the comprehensive understanding of modern spine anatomy, we abandoned laminectomy in our procedure, applied a mid-waist skin incision, dissect to the paraspinal muscles where you could easily reach the facets by separating between the multifidus and longissimus, enlarge the canal by performing resection along ligamentum flavum and the inner broader of the articular process, remove enough tissue till you could expose the traversing root and the disc space, this method could achieve a limited but precise and effective decompression with not taking out all of the articular process. Once the anatomy mark of the pedicle is located (usually would be at the central area of the incision), pedicle screws placement would be precise and easy without struggling with muscle traction. The following procedures would be Spondylolisthesis reduction, discectomy and interbody fusion.</p><p><b>RESULTS</b>Post-op patients of study group all showed significant improvement of pain symptoms, VAS reduced from 7.14 + or - 1.8, pre-op to 1.39 + or - 0.72 post-op, narrowed disc space regained height, spondylolisthesis reached anatomic reduction, no complications such as pedicle screw misplacement and nerve root damage were found, the lumbar spine regained it's physiological lordosis structure. Significant difference is discovered (P < 0.001) in statistic study concerning the rate of intractable low back pain between pre-op and post-op.</p><p><b>CONCLUSIONS</b>Applying low back surgery through posterior para-median approach could directly reach the inferior/superior facets and the "soft" structures of the spinal canal, expose the exact decompression region and anatomy mark of the pedicle in the central surgical field without strong retraction on the para-spinal muscles. This approach has the advantage of lowering the surgical difficulty of implantation, reducing the risk of nerve damage and is also a minimum invasive procedure. In many cases, laminectomy is unnecessary, leaving the lamina intact could preserve the physiological anatomy of the spine.</p>

Mutational analysis of EGFR and K-RAS in Chinese patients with non-small cell lung cancer / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate gene mutations of the epidermal growth factor receptor (EGFR) and K-RAS in Chinese non-small cell lung cancers (NSCLCs).</p><p><b>METHODS</b>Mutations of exons 18, 19 and 21 of the EGFR and codons 12, 13 of the K-RAS in 101 NSCLCs were detected by PCR-amplifying and gene sequencing, and the relationship between mutations and clinical characters of NSCLCs and response to gefitinib were analyzed.</p><p><b>RESULTS</b>Overall, 26 EGFR mutations (25.7%), 3 K-RAS mutations (2.9%) were detected, and EGFR mutation frequencies in adenocarcinomas, nonsmoker and female were found to be high (44.2%, 65.7% and 48.3% respectively). Nine out of 10 gefitinib treated patients with disease control was found with EGFR mutation.</p><p><b>CONCLUSION</b>The data suggest that mutation frequency of EGFR in NSCLCs from Chinese patients is higher than that of western ethnicities, such mutations are well correlated with tumor response to gefitinib, and gefitinib is more fit for Chinese NSCLC patients.</p>

Effect of GMCSF-absence on neovascularization during wound healing / 中华整形外科杂志

<p><b>OBJECTIVE</b>To study the effect of GMCSF-absence on the rate of wound healing and neovascularization during wound repair.</p><p><b>METHODS</b>30 wild type (WT) mice and 30 GMCSF- absence mice (GMCSF-KO) were obtained. They were received full thickness skin wound (0.8 cm x 0.8 cm) in each side of midline after deeply anesthesia. In the different post-injury time points, the wound sites were digitally photographed to calculate the percentage of wound closure by using computer image analyses software. The wound specimens were also obtained dynamically for immunohistological analysis of CD31 at wound site.</p><p><b>RESULTS</b>The analysis of the wound closure showed that wound healing in GMCSF-KO mice was delayed significantly comparing with that in WT mice from the day 3 post-wounding. At days 7 and 10 after wounding significantly more numbers of blood vessels were formed in the WT controls compared to the GMCSF-KO mice.</p><p><b>CONCLUSIONS</b>GMCSF-absence inhibits neovascularization during wound repair and leads to the delay of wound healing.</p>

Variability analysis of S2 gene of SARS-CoV / 南方医科大学学报

<p><b>OBJECTIVE</b>To determine the sequence of S2 gene of SARS-associated coronavirus (SARS-CoV) GD322 and analyze the phyletic evolution of S2 gene.</p><p><b>METHOD</b>S2 gene fragment was amplified from SARS-CoV GD322 genome with RT-PCR and ligated to pGEM-T vector for sequence analysis after transformation of the plasmid into E. coli DH5a. The variability of S2 genes and S2 proteins from 12 strains isolated in the early, intermediate and advanced stages of the SARS outbreak were analyzed and the phylogenetic tree was constructed with Lasergene, Clustal X, DNAman and Treeview. T cell antigen epitopes of S2 protein were predicted on the basis of Internet database.</p><p><b>RESULT</b>With the epidemic spread of SARS-CoV, the S2 genes of the virus tended to become stable. Homology of S2 genes of SARS-CoV isolated in advanced stage of the outbreak reached 99.9%. Prediction of T cell antigen epitope showed that mutation at the 57th amino acid effected T cell antigen epitope.</p><p><b>CONCLUSION</b>S2 gene of GD322 SARS-CoV is relatively stable during the epidemic spread of the virus, and mutation at the 57th amino acids of S2 protein may affect the T cell antigen epitope.</p>

Construction and identification of genomic cDNA subclones of dengue 2 virus NGC strain / 南方医科大学学报

<p><b>OBJECTIVE</b>To construct the cDNA subclones spanning the entire genome of dengue 2 virus NGC strain for further construction of full-length infectious viral cDNA clone.</p><p><b>METHODS</b>Two pairs of primers were designed according to the restriction endonuclease sites in the viral genome of dengue 2 virus NGC strain. After viral RNA extraction from the brain of infected new-born mice, two parts of full-length viral cDNA were amplified by long RT-PCR and cloned into the vector pCR-XL-TOPO. The partial sequence of the recombinant plasmid was determined.</p><p><b>RESULTS AND CONCLUSION</b>Sequence analysis and digestion with restriction enzymes demonstrated that the two cDNA subclones were specific for dengue 2 virus NGC strain, suggesting the successful construction of the two cDNA subclones of dengue 2 virus NGC strain.</p>

The porcine alpha1, 3 galactosyltransferase gene siRNA targeted heterozygous hepatocyte negative express GT / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To study whether the porcine alpha1, 3 galactosyltransferase gene siRNA targeted heterozygous hepatocyte negatively expresses GT mRNA and resists to the cytotoxicity of nature antibody in human serum.</p><p><b>METHODS</b>The porcine alpha1, 3 galactosyltransferase gene siRNA targeted vector (pPNTloxPGTsiRNA) were construct with pPNTloxPGT and pMXSV/U6 vector. Positive-negative selection was used to produce a heterozygous pPNTloxPGTsiRNA knockout (+/-) clone. The GT mRNA expressions were detected with northern blot. Complement-mediated NAb cytotoxicity after incubation of hepatocytes with NAbs and complement was determined using 3- (4, 5-dimethylthiazol-2-yl)-5-(3-carboxymethyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium(MTS, tetrazolium salt) colorimetric assay.</p><p><b>RESULTS</b>The pPNTloxPGTsiRNA targeted porcine hepatocyte (+/-) negative express GT mRNA. Only 14% to 18% cytotoxicity can be detected at the highest serum concentration. The pPNTloxPGT targeted porcine hepatocyte (+/-) express GT mRNA just as the wild type porcine cells and the cytotoxicity are 77% to 83%.</p><p><b>CONCLUSION</b>The porcine a1, 3 galactosyltransferase gene siRNA targeted heterozygous hepatocyte (+/-) negative express GT and resisted to nature antibody in human serum.</p>

Advances in the Infection of Human Parvovirus B19 / 微生物学通报

Increased recognition of human parvovirus B19,as a significant human pathogen has resulted in intensive researches to understand the pathogenesis of B19 infection,to elucidate the nature of Th1-mediated cellular immune response,to improve diagnostic strategy that is deployed to detect B19 infection and blood-product contamination,and to lay a foundation that should contribute to the development of an effective vaccine to prevent B19 infection.In this review,the biologic characteristics and the pathogenesis of human parvovirus B19,and B19-related manifestations as well as laboratory diagnostic methods for B19 infection were comprehensively discussed.

A QUANTITATIVE STUDY ON THE SYNAPTIC PLASTICITY IN THE MOLECULAR LAYER OF DENTATE GYRUS OF KAINATE RAT / 解剖学报

Objective In order to investigate the synaptic plasticity in dentate gyrus after seizures and axonal and dendrtic sprout- ing induced by KA administration. Methods The density of synapses, the curvature forms of synaptic interface were studied under electron microscope. Results 1 .The density of the synapse is decreased obviously 3 days after KA injection, while the density of synapses is increased to control level 7 days after KA injection. 2. Compare with the curvation forms of synaptic interface of control animals and 3days after KA administration animals, the amount of smile synapses is significantly decresed and the amount of frown synapses is significantly increased in the moleculous layer of dentate gyrus 7 days after KA injection. Conclusions 1 .This result demonstrates that the axonal and dendritic sprouting of dentate granule cells is functional. 2. The increase of frown synapse is related to the release of glutamate of sprouting mossy fibers.