Outbreak of infections caused by Group A Streptococcus after modified radical mastectomy.

BACKGROUND: Eight infections occurred after modified radical mastectomies in a tertiary-care hospital. Group A streptococci (GAS) were isolated from three of the eight patients. METHODS: To control the outbreak, an epidemiologic investigation was conducted, and healthcare workers were screened for pathogens. Strains isolated from healthcare workers were compared with patient strains by emm typing. RESULTS: One surgeon attended one of the eight operations and observed the other seven. Streptococcus strains from the hands of this surgeon were identical to the patient strains. After the surgeon was suspended from duty and underwent eradication treatment, the outbreak was controlled. CONCLUSIONS: This outbreak of GAS infection is believed to have occurred by airborne transmission. Suspending patient care by healthcare workers who carry the causative GAS in a site(s) other than the respiratory tract for only the first 24 h they are receiving chemoprophylaxis may not be long enough. Sampling of the hands of healthcare workers during an investigation of nosocomial GAS infection is valuable.

High temperature reduces the proliferation of and occludin expression in rat Sertoli cells in vitro / 中华男科学杂志

<p><b>OBJECTIVE</b>To explore the action mechanisms of temperature in male infertility or subfertility by observing the effects of different temperatures on the proliferation of and occludin (OCLN) expression in rat Sertoli cells in vitro.</p><p><b>METHODS</b>We isolated Sertoli cells from the testis of male Wistar rats, and performed oil red O staining and immunohistochemistry to identify their FasL. We cultured the Sertoli cells at 34 degrees C (control group) and at 35, 36, 37, 38 and 39 degrees C (experimental groups) for 4 days. Then we measured their proliferation by CCK-8 assay, observed their morphology and structure by hematoxylin-eosin staining, and determined their OCLN expression level by Western blotting and immunofluorescence.</p><p><b>RESULTS</b>The purity of the isolated Sertoli cells was (96.20 +/- 1.95)%. CCK-8 assay indicated that the proliferation of the Sertoli cells was increased between 34 and 36 degrees C, and decreased at 36-39 degrees C. The pyknotic nuclei and fragmentation of the Sertoli cells were more obvious at > 36 degrees C. Western blot and immunofluorescence showed the highest level of OCLN expression at 36 degrees C, which, however, decreased while the temperature rose above 36 degrees C (P < 0. 01).</p><p><b>CONCLUSION</b>High temperature (> 36 degrees C) inhibited the proliferation of rat Sertoli cells in vitro, and decreased the expression of OCLN, which suggests that a higher temperature above 36 degrees C may reduce male fertility by affecting the proliferation of Sertoli cells and integrity of the tight junction among Sertoli cells or Sertoli cells and other cells.</p>

Construction of lentivirus vector containing human homeobox gene HOXB4 and its expression in human umbilical cord mesenchymal stem cells / 中国实验血液学杂志

This study was purposed to construct lentivirus vector containing human homeobox gene HOXB4 and explore changes of human umbilical cord mesenchymal stem cells (HUCMSC) after infected with HOXB4 mediated by lentivirus. PCR amplification was performed to obtain HOXB4, which was cloned in lenti-shuttle vector. Four-plasmid lentivirus packaging system was used to transfect HEK293T cells. After 48 h, lentivirus Lenti-HOXB4 was harvested and lentivirus titer was determined. Lenti-HOXB4 was used to infect HUCMSC. The infected cells were observed under inverted fluorescence microscope to determine the optimal multiplicity of infection (MOI). Meanwhile, RT-PCR, immune fluorescence staining, CCK-8 and flow cytometry (FCM) were used to determine the expression of HOXB4 and its effect on cell growth. The results indicated that lenti-HOXB4 was successfully obtained by co-transfecting the 293T cells with four plasmids. The determined virus titer was 3×10(8) TU/ml; when MOI was 20. Lenti-HOXB4 had a high transfection rate in HUCMSC, over 80%. In HUCMSC infected with lenti-HOXB4, the expression of target gene could be detected both at mRNA and protein levels. It could promote the proliferation of HUCMSC. FCM results indicated HOXB4 gene did not significantly influence the surface marker of HUCMSC. It is concluded that HOXB4 gene can promote the high proliferation of HUCMSC and does not significantly influence the expression of the surface marker of HUCMSC.

Construction and identification of a eukaryotic expression vector containing human homeobox gene / 中国实验血液学杂志

In order to investigate the special role of HOXB4 in expansion and self renewal of hematopoietic stem cells, the cDNA of HOXB4 was extracted and cloned from umbilical cord blood mononuclear cells by using RT-PCR. Then the eukaryotic expression bicistronic plasmid vector pIRES2-EGFP/HOXB4 was designed and constructed after cutting HOXB4 and pIRES2-EGFP respectively by restriction enzyme EcoRI and BamHI. The recombinant plasmid was delivered into competent cells of Escherichia coli. The successful construction of plasmid was confirmed by the identification of endonuclease cutting and sequencing. The results showed that the HOXB4 cDNA was cloned successfully from umbilical cord blood mononuclear cells and the recombinant eukaryotic expression bicistronic plasmid vector was constructed, and then introduced it into 293T cells successfully. It is concluded that a pIRES2-EGFP/HoxB1 eukaryotic expression bicistronic plasmid vector has been constructed successfully, which results provide a useful material basis for exploration of HoxB4 function in the proliferation and differentiation of hematopoietic cells.

High-risk factors of progressive hemorrhagic injury after acute traumatic brain injury and its time for first scheduled brain CT / 中华神经医学杂志

Objective To investigate the high-risk factors of progressive hemorrhagic injury (PHI)after acute traumatic brain injury(TBI)and discuss its time for first scheduled brain CT.Methods Retrospective analysis of clinical data of 329 adult patients with blunt TBI,admitted to second affiliated hospital of Suzhou University from August 2009 to July 2010,was performed.Patients were divided into PHI high-risk group and non-PHI high-risk group based on whether clinical symptoms worsened before the first routine scheduled brain CT;and control study was established. Results Forty-one patients from the PHI high-risk group were performed first routine scheduled brain CT ahead of time([3.67±0.96]h)for appearing worsened clinical symptoms,while 288 patients with non-PHI high-risk group were performed first routine brain CT as schedule(8.38±3.03 h);significant difference on the time for the first brain CT was noted between the 2 groups(P<0.05).Statistical differences in aspects of intracranial hematoma volume>10 mL,intracranial hematoma type≥2,associated subarachnoid hemorrhage on initial brain CT,disturbance of consciousness,pupil dilation and scores of Glasgow Coma Scale≤12 on admission were noted between the 2 groups(P<0.05),and statistical differences in aspects of reduced platelet(Plt),prolonged prothrombin time(PT),prolonged activated partial thromboplastin time(APTT),decreased Fibrinogen(FIB)on admission,bilateral brain injury,associated brain contusion,and skull fracture with epidural hematoma on initial brain CT were found between the 2 groups(P<0.05).Logistic regression analysis showed that intracranial hematoma volume>10 mL on initial brain CT, disturbance of consciousness and pupil dilation on admission were predictors for PHI high-risk patients (P<0.05). Conclusion For patients with intracranial hematoma volume>10 mL on initial brain CT, disturbance of consciousness and pupil dilation on admission within 2 h of TBI, first routine scheduled brain CT should be performed within 3-4 h of TBI or even earlier.