With development of wide-host-range vector systems,Tn5 transposon and its derivative vectors have been widely applied to genetic research of gram-negative bacteria.The applications of Tn5 transposon mutagenesis technology to genetic researches of bacteria were briefly discussed,including researches on biological control mechanisms of biocontrol bacteria,identification of bacterial essential genes,discovering virulence genes of bacterial pathogens,characterization of metabolism regulatory genes and genetic improvements of bacteria.

OBJECTIVETo investigate the expressions of thyroid transcription factor-1 (TTF-1), the type II alveolar epithelial cells (AECII)-specific marker, and vimentin, the fibroblast-specific marker, in the lungs of neonatal mice with bronchopulmonary dysplasia (BPD) and explore the pathogenesis of BPD.

METHODSNeonatal mice were exposed to hyperoxia to induce BPD, and pathological changes in the lung tissues were examined. At 3, 7, 14 and 21 days after the exposure, the protein and mRNA expressions of TTF-1 and vimentin were detected by double-labeled immunofluorescence assay and real-time PCR, respectively.

RESULTSCompared with the neonatal mice exposed in normal air, those with hyperoxic exposure showed developmental disorders and collagen deposition in the lung tissues. The protein expression of TTF-1 decreased while vimentin expression increased in the lung tissues, where their co-expression was observed at 14 and 21 days after the exposure. TTF-1 mRNA expression decreased markedly (P<0.05) and vimentin mRNA increased significantly in the lung tissues at 21 days after hyperoxic exposure of the mice (P<0.05).

CONCLUSIONHyperoxia-induced transition of AECII to fibroblasts may play an important role in pulmonary fibrosis in neonatal mice with BPD.

Animals ; Animals, Newborn ; Disease Models, Animal ; Female ; Hyperoxia ; Lung ; metabolism ; pathology ; Lung Diseases ; metabolism ; pathology ; Mice ; Mice, Inbred C57BL ; Nuclear Proteins ; metabolism ; RNA, Messenger ; genetics ; Thyroid Nuclear Factor 1 ; Transcription Factors ; metabolism ; Vimentin ; metabolism

OBJECTIVETo investigate the mechanism and the suppression effect of human cytomegalovirus (HCMV) on hematopoietic system.

METHODSSemi-solid culture system was used to observe the effect of HCMV AD169 strain on colony forming unit granulocyte/macrophage (CFU-GM), CFU-erythroid (CFU-E), CFU-multipotent (CFU-Mix) and CFU-megakaryocyte (CFU-MK) growth. The techniques of in situ polymerase chain reaction (IS-PCR) and polymerase chain reaction (PCR) were used to demonstrate the existence of HCMV DNA in the colony cells of cultured CFU-GM, CFU-Mix, CFU-MK and CFU-E, respectively. The immediate early antigen (IEA) mRNA in CFU-MK and late antigen (LA) mRNA in CFU-E were detected by reverse transcriptase-polymerase chain reaction (RT-PCR). HCMV early protein P52 was detected with immunohistochemical technique.

RESULTSHCMV AD169 suppressed the differentiation and proliferation of CFU-GM, CFU-E, CFU-Mix and CFU-MK in vitro significantly (P < 0.05). The suppression was dose-dependent. HCMV DNA was successfully detected in CFU-GM, CFU-Mix, CFU-MK colony cells from viral infection groups by IS-PCR, and was detected in CFU-E by PCR, while it was negative in blank control or mock control groups. CFU-MK colony cells expressed HCMV IEA mRNA with the size of 340 bp in virus infection groups of 10(3) plague forming unit (PFU), 10(4) PFU and 10(5) PFU, respectively. The HCMV LA mRNA was detected by RT-PCR and was 263 bp long in positive control group of HCMV-infected human embryonic fibroblasts. The expression of HCMV LA mRNA in CFU-E was negative. The early protein P52 of HCMV in 10(4) PFU group was also identified by immunohistochemical staining.

CONCLUSIONHCMV AD169 strains inhibited the differentiation and proliferation of CFU-GM, CFU-E, CFU-Mix and CFU-MK by the infection of the hematopoietic progenitors. HCMV might cause the suppression of hematopoiesis by direct infection, which is thought to be one of the reasons of HCMV infection associated with thrombocytopenia, neutropenia and anemia.

Colony-Forming Units Assay ; Cytomegalovirus ; genetics ; DNA, Viral ; genetics ; Erythrocytes ; virology ; Hematopoietic System ; cytology ; virology ; Humans ; Megakaryocytes ; virology ; Multipotent Stem Cells ; virology ; Polymerase Chain Reaction

OBJECTIVETo explore the effect of serum restriction on the invasiveness and expressions of insulin-like growth factor-1 (IGF-1) and matrix metalloproteinase-2 (MMP-2) in human trophoblast HTR-8/SVneo cells in vitro.

METHODSHTR-8/SVneo cells were cultured in the presence of 1%, 5%, or 10% fetal bovine serum (FBS) for 48 h. Fluorescence quantitative PCR and immunofluorescence staining were employed to examine the changes in IGF-1 and MMP-2 expressions at both the mRNA and protein levels in HTR-8/SVneo cells; MTT assay and Transwell invasion assay were used to assess the changes of the cell proliferation and the cell invasion ability, respectively. MMP-2 expression, cell proliferation and invasiveness were also assessed in the cells treated with recombinant human IGF-1.

RESULTSHTR-8/SVneo cells exhibited significantly lowered cell proliferation in cultures containing low concentrations of FBS (P<0.05). The expressions of IGF-1 and MMP-2 at both mRNA and protein levels were significantly down-regulated and the invasiveness was significantly lowered in cells cultured in the medium containing 1% FBS as compared with those of cells cultured in the presence of 5% and 10% FBS (P<0.05). Treatment of the cells with recombinant human IGF-1 significantly up-regulated MMP-2 expression (P<0.05) and increased the cell invasiveness (P<0.05).

CONCLUSIONSFBS restriction down-regulates IGF-1 expression in human trophoblast HTR-8/SVneo cells and suppress the cell invasiveness possibly by suppressing MMP-2 expression. Treatment with recombinant human IGF-1 can up-regulate MMP-2 expression and promote the invasiveness of HTR-8/SVneo cells.

OBJECTIVETo improve the diagnosis and treatment of far advanced prostate cancer without clinically detectable bone metastasis.

METHODSCancer metastatic lesions were found in the liver and lungs respectively of two patients on routine medical examination, and only an abnormally elevated level of the serum prostate specific antigen (PSA) was observed in the following system examinations. The patients were diagnosed as having prostate cancer by prostate biopsy. MRI showed a discontinued prostate capsule, and ECT revealed no bone metastasis. Diagnostic treatment was conducted by giving LHRHa combined with antiandrogens. One of the patients underwent surgical castration at 12 months, and both received intensity modulated radiation therapy (80 Gy) at 15 and 18 months, respectively.

RESULTSThe metastatic lesions in the liver and lungs of the patients were either absent or significantly reduced after treated by maximal androgen blockade for 3 months, and all disappeared after 6 months'treatment, with the PSA level stabilized at less than 0.02 microg/L in one patient, and around 0.5 microg/L in the other. Antiandrogen treatment was suspended after radiotherapy. The results of liver, lung and bone scanning were normal during the 12-month follow-up, and the PSA level was below 1.0 microg/L.

CONCLUSIONRemote metastasis of prostate cancer may occur in ectosteal organs first, which deserves special attention. A combination of different treatment methods promises satisfactory results.

Aged ; Humans ; Liver Neoplasms ; secondary ; Lung Neoplasms ; secondary ; Male ; Neoplasm Metastasis ; Prostatic Neoplasms ; diagnosis ; pathology ; therapy

ObjectiveTo investigate the effect of mucin 1 (MUC1) on the proliferation and apoptosis of nasopharyngeal carcinoma (NPC) and its regulatory mechanism. MethodsThe 60 NPC and paired para-cancer normal tissues were collected from October 2020 to July 2021 in Quanzhou First Hospital. The expression of MUC1 was measured by real-time quantitative PCR (qPCR) in the patients with PNC. The 5-8F and HNE1 cells were transfected with siRNA control (si-control) or siRNA targeting MUC1 (si-MUC1). Cell proliferation was analyzed by cell counting kit-8 and colony formation assay, and apoptosis was analyzed by flow cytometry analysis in the 5-8F and HNE1 cells. The qPCR and ELISA were executed to analyze the levels of TNF-α and IL-6. Western blot was performed to measure the expression of MUC1, NF-кB and apoptosis-related proteins (Bax and Bcl-2). ResultsThe expression of MUC1 was up-regulated in the NPC tissues, and NPC patients with the high MUC1 expression were inclined to EBV infection, growth and metastasis of NPC. Loss of MUC1 restrained malignant features, including the proliferation and apoptosis, downregulated the expression of p-IкB、p-P65 and Bcl-2 and upregulated the expression of Bax in the NPC cells. ConclusionDownregulation of MUC1 restrained biological characteristics of malignancy, including cell proliferation and apoptosis, by inactivating NF-κB signaling pathway in NPC.

BACKGROUNDGlobally, the proportion of child deaths that occur in the neonatal period remains a high level of 37-41%. Differences of cause in neonate death exist in different regions as well as in different economic development countries. The specific aim of this study was to investigate the causes, characteristics, and differences of death in neonates during hospitalization in the tertiary Neonatal Intensive Care Unit (NICU) of China.

METHODSAll the dead neonates admitted to 26 NICUs were included between January l, 2011, and December 31, 2011. All the data were collected retrospectively from clinical records by a designed questionnaire. Data collected from each NICU were delivered to the leading institution where the results were analyzed.

RESULTSA total of 744 newborns died during the 1-year survey, accounting for 1.2% of all the neonates admitted to 26 NICUs and 37.6% of all the deaths in children under 5 years of age in these hospitals. Preterm neonate death accounted for 59.3% of all the death. The leading causes of death in preterm and term infants were pulmonary disease and infection, respectively. In early neonate period, pulmonary diseases (56.5%) occupied the largest proportion of preterm deaths while infection (27%) and neurologic diseases (22%) were the two main causes of term deaths. In late neonate period, infection was the leading cause of both preterm and term neonate deaths. About two-thirds of neonate death occurred after medical care withdrawal. Of the cases who might survive if receiving continuing treatment, parents' concern about the long-term outcomes was the main reason of medical care withdrawal.

CONCLUSIONSNeonate death still accounts for a high proportion of all the deaths in children under 5 years of age. Our study showed the majority of neonate death occurred in preterm infants. Cause of death varied with the age of death and gestational age. Accurate and prompt evaluation of the long-term outcomes should be carried out to guide the critical decision.

Cause of Death ; China ; Female ; Hospital Mortality ; Humans ; Infant ; Infant Mortality ; Infant, Newborn ; Infant, Newborn, Diseases ; mortality ; Intensive Care Units, Neonatal ; statistics & numerical data ; Male ; Perinatal Death ; Retrospective Studies