Electromagnetic Fields ; Environmental Exposure ; Humans ; Radiation Dosage ; Threshold Limit Values

Spermatogenesis is a complex process. Current knowledge about human spermatogenesis is mainly based on the mouse model while little is known about the initial stage of this fundamental process in humans. The establishment of the model of spermatogenesis in vitro may contribute to an overall understanding of male germ cell development, an insight into the mechanisms of infertility, and clinical management of male infertility. This review summarizes current knowledge about the generation of germ cell-like cells from induced pluripotent stem cells (iPSCs) in vitro and discusses the potential application of iPSCs in the treatment of male infertility.
Animals ; Cell Differentiation ; Germ Cells ; Humans ; Induced Pluripotent Stem Cells ; Infertility, Male ; therapy ; Male ; Mice ; Spermatogenesis

BACKGROUND:Previous research has demonstrated human bone marrow mesenchymal stem cells(HMSCs)differentiate into hepatocyte-like cells;however,biological characteristics and differentiation mechanism remain unclear,and differentiation system remains immature.OBJECTIVE:To investigate the feasibility of hepatocyte growth factor(HGF)and epidermal growth factor(EGF)to induce the differentiation of HMSCs into hepatocyte-like cells.METHODS:HMSC5 were obtained from patients with esophageal cancer and were separated by density gradient centrifugation combined with attachment method.The phenotypes of MSCs were identified by flow cytometry.The third-passage HMSCs were divided into four groups:HGF(adding 20 μg/L HGF),EGF(adding 20 μg/L EGF),HGF+EGF,and blank control groups.Morphology was observed using inverted microscope.At days 7 and 14 after induction,α-fetoprotein and albumin mRNA expressions were detected using RT-PCR assay.RESULTS AND CONCLUSION:The HMSCs did not express hematopoietic cell CD34 and CD35,but strongly expressed β1-integrin CD29 and matrix receptor CD44.HMSCs changed from long fusiform shape to polygon or similar round shape in the HGF,EGF,and HGF+EGF groups.At days 7 and 14 after induction,α-fetoprotein and albumin mRNA expressions were positive.However,polygon cells were not observed in the blank control group,and α-fetoprotein and albumin mRNA expressions were negative.This suggested that HGF,EGF,and HGF+EGF could induce the differentiation of HMSCs into hepatocyte-like cells;however,their differentiation ability still needs to be further semi-quantitatively analyzed using immunohistochemical staining.

[ ABSTRACT] AIM:To study the influence of insulin resistance on fatty liver in the mice fed with high-fat diet (HFD).METHODS:Male 8-week-old C57BL/6J mice were randomly divided into HFD group (with 60% calories by high saturated fatty acid) and control group (with chow diet).The mice in both groups were fed for 12 weeks.The body weight, liver weight, serum triglyceride (TG) and total cholesterol (TC), and blood glucose and insulin levels were meas-ured.Hyperinsulinemic euglycemic clamp experiment was applied to reflect insulin sensitivity .The lipid deposition in the liver was analyzed by HE staining , Sudan IV staining and measurement of liver fat content .The phosphorylation levels of IRS1 and Akt, and the protein levels of SREBP-1 and FAS were determined by Western blot to reflect the activities of insu-lin signaling and lipid synthesis .RESULTS:Compared with control group , the body weight and liver weight were signifi-cantly increased in HFD group .TG and TC contents in serum and liver tissues were remarkably increased in HFD group . High-fat diet induced insulin resistance , as evidenced by increased serum insulin levels , reduced glucose infusion rate and decreases in IRS1 and Akt phosphorylation levels .In livers of HFD group, HE staining showed that the cytoplasm of hepa-tocytes was filled with vacuoles .Sudan IV staining also displayed that many different sizes of red lipid drops existed in the hepatocytes , and the protein levels of SREBP-1 and FAS were significantly increased .In primary normal hepatocytes with exogenous oleic acid intervention for 48 h, the phosphorylation levels of IRS 1 and Akt were reduced , and the protein ex-pression of SREBP-1 and FAS was significantly increased in a dose-dependent manner .CONCLUSION: Feeding with HFD leads to insulin resistance , resulting in activation of lipid synthesis and accumulation of lipid deposition in the liver , thus inducing fatty liver .

Objective: To determine the effects of intravenous anesthetics (fentanyl,midazolam and propofol )on inflammatory responses. Method: We employed carrageenan-sensitized endotoxemic rabbit model. Thirty-two New Zealand rabbits were randomly assigned to one of four groups,control group(no anesthetic was used), fentanyl group, midazolam group and propofol group. Different anesthetics were used intravenously for anesthesia induction and maintenance according to the group classification. Meanwhile, all animals were mechanically ventilated, then, 2?g?kg~(-1) lipopolysaccharide(LPS) were injected for endotoxin challenge. Result:In all groups, serum tumor necrosis factor (TNF)activity began to increase at 30 min,reached its maximal level at 60 min,and tended to decrease at 120 min after (LPS) challenge,and the significant increase of TNF activity was associated with development of hypotension. Meanwhile,serum phospholipase A_2(PLA_2)activity began to increase at 60 min and persisted in going up within 2h. Those animals,with continuous infusion of these three different anesthetics and mechanical ventilation,had much lower peak level of TNF and higher mean arterial pressure (MAP)than control levels, but their changes of serum PLA_2 activity had no significant difference from control level. Conclusion: With mechanical ventilation, intravenous infusion of these anesthetics can reduce LPS induced injury in the acute phase of endotoxemia, probably by the inhibition of TNF production.

Electromagnetic Fields ; Threshold Limit Values

Nasopharyngeal carcinoma (NPC) poses serious health problems in Southern China and yet the molecular mechanism of the carcinogenesis remains unclear. We used modern proteomic technologies to compare the protein expression profiles between the NPC cell lines (HNE1 and CNE1 ) and an immortalized nasopharyngeal epithelial cell line NP69 to identify cancer related proteins. Cell lysates were separated by two-dimensional gel electrophoresis (2 DE ) and analyzed by PDQuest software. The differentially expressed proteins were identified by matrix-assisted laser desorption/ionization tandem time-of-flight mass spectrometry (MALDI-TOF/TOF-MS). We discovered 15 up-regulated proteins and 18 down-regulated proteins in both HNE1 and CNE1 cell lines compared with NP69. These proteins are correlative with various functions, such as cell proliferation, apoptosis, cancer metastasis, metabolism, cytoskeleton and signal transduction. Western blotting analyses were further carried out to verify the differential expression of individual proteins. Several identified proteins in our research might be used as potential molecular markers to understand the molecular mechanism of NPC development and metastasis, and might be used as candidate targets for NPC treatments.

Objective To evaluate the relationship between emergence agitation (EA) during recovery from general anesthesia and postoperative cognitive dysfunction (POCD).Methods Two hundred and eighty ASA Ⅰ or Ⅱ patients,aged 18-70 yr,weighing 52-80 kg,undergoing elective surgery,were included.Anesthesia was induced with midazolam,fentanyl,propofol and cisatracurium.The patients were tracheal intubated and mechanically ventilated.Anesthesia was maintained with remifentanil,propofol and cisatracurium.EA was assessed at 15-40 min after extubation by using Post-operative Quality Recovery Scale and the cognitive function was assessed at day 1 before operation and days 1-7 after operation.Patients were divided into POCD or nonPOCD group according to the occurrence of POCD.The general data of patients,preoperative complications and types of surgery were recorded.If there was significant difference between the 2 groups,the factor was analyzed using multi-factor logistic regression to select the risk factor for incidence of POCD.Results The incidence of POCD was 40.7 ％.The results of logistic regression analysis showed that the dangerous degree of the risk factors for POCD in order from high to low were emergence agitation,duration of anesthesia and age.Conclusion EA during recovery from general anesthesia is an independent risk factor for POCD.

AIM: To investigate whether Ligustrazine(LTZ) has an effect on the changes of protein kinase C(PKC) signaling pathway induced by inflammatory mediators involved in asthma in normal human peripheral blood lymphocytes (PBL). METHODS: 10 mL peripheral venous blood was obtained from each of 63 health humans and treated as follows. The activities of PKC from cytosolic and membrane fractions in PBL were measured by -ATP-catalyzing assay, after PBL had been isolated and performed by following processes: (1) First: three groups treated with 5 g/L LTZ(n=6) or 5 ?mol/L Ro31-8220 (n=6); Paired untreated PBL served as control of this group, as well as the negative controls of the following groups(n=6); (2)Second : three groups treated with 100 nmol/L Methacholine (Mch, n=5), 5 g/L LTZ+100 nmol/L Mch(n=5)or 5 ?mol/L Ro31-8220(a PKC inhibitor)+100 nmol/L Mch(n=5); (3)Third: three groups treated with 100 nmol/L histamine, 5 g/L LTZ+100 nmol/L histamine(n=5) or 5 ?mol/L Ro31-8220+100 nmol/L histamine(n=5); (4)Fourth: three groups treated respectively with 100 nmol/L PMA(a PKC activator, n=5), 5 g/L LTZ+100 nmol/L PMA(n=5) or 5 ?mol/L Ro31-8220+100 nmol/L PMA(n=5). RESULTS: (1)LTZ had no effect on the activities of PKC in inactive PBL in normal humans; (2) Methacholine or histamine resulted in an increase in membrane PKC activity of normal human PBL, which was partly suppressed by LTZ (all P

This study was aimed to evaluate impacts on immune regulation with spleen-strengthening and kidney-tonifying method among advanced malignant tumor patients. The enrolled advanced malignant tumor patients were randomly divided into the control group and the treatment group. The control group was treated with conventional treatment plan. The treatment group was treated with spleen-strengthening and kidney-tonifying Chinese herbs on the basis of conventional treatment plan for three months. Clinical effect, integral of clinical symptom (ICS), T-lym-phocyte subsets, and drug safety index were observed and detected before and after treatment. The results showed that the effective rate and response rate in the control group were 31.1% and 71.1%, respectively. And the effective rate and response rate in the treatment group were 54.2% and 85.4%, respectively. The treatment group was better than the control group (P< 0.05). Compared to the control group, the treatment group had obvious regulation on T-lymphocyte subsets. The improvement on ICS in the treatment group was better than the control group (P < 0.05). There was no obvious adverse reaction with the application of Chinese herbs. It was concluded that the spleen-strengthening and kidney-tonifying method can improve clinical effect, life of quality, and reduce adverse reaction a-mong advanced malignant tumor patients. Its mechanism may be through the regulation of immune function.