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

Electromagnetic Fields ; Threshold Limit Values

[ 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.

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.

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

Objective To investigate the application value of transcranial Doppler ultrasonography(TCD) in critically ill children with cerebral dysfunction.Methods We detected the cerebral blood flow parameters[systolic velocity(Vs),mean velocity(Vm),end of diastolic velocity(Vd),pulsatility index(PI),resistance index(RI)] of middle cerebral artery in cerebral dysfunction group(n=20) and control group(no cerebral dysfunction,n=20),and observed the differences of those parameters between two groups.Children in cerebral dysfunction group were also divided into groups according to Glasgow Coma Score(GCS) and prognosis.The differences of each TCD parameter in diverse groups divided by GCS and by prognosis were analysed.Children in cerebral dysfunction group were checked TCD everyday until TCD parameters were normal.The relation between the days of TCD parameters′ reaching normal and GCS,duration of disorder of consciousness with correlation analysis were analysed.Results Vs,PI,RI in cerebral dysfunction group were higher than those in control group,while Vd was lower (P<0.05).(2)PI in the group of GCS less than 6 points(0.91±0.21) was higher than that in group of GCS 7-13 points(0.83±0.14)(P<0.05).The other parameters between two groups of GCS less than 6 points and GCS 7-13 points were not significantly indistinctive.Between the good prognosis group and the bad prognosis group,there were no significant differences in all parameters.(3) The days of TCD parameters′ reaching normal were negatively correlated with GCS(r=-0.653,P<0.01),but positively correlated with the duration of disorder of consciousness(r=0.923,P<0.01).Conclusion The cerebral hemodynamics of children with cerebral dysfunction is abnormal,the more serious cerebral dysfunction,the higher PI and the longer time for regaining normal TCD parameters.Constantly monitoring TCD could reflect the changes of cerebral hemodynamics and is valuable to assess the state of illness and prognosis.

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.

[ ABSTRACT] AIM:To observe the effect of endogenous nitric oxide synthase ( NOS) inhibitor asymmetric dimeth-ylarginine ( ADMA ) and its signaling pathways on NO levels and skeletal muscle contractility in 4-week running rats. METHODS:The 4 weeks running rat model was established.The twitch tension, tetanic tension and the fatigue test of sole-us muscle induced by electrical stimulation ex vivo were detected.The ATP content, mitochondrial DNA levels and the mR-NA expression of peroxisome proliferator-activated receptor γcoactivator-1α(PGC-1α), nuclear respiratory factor (NRF) were measured to reflect the mitochondrial function and biosynthesis in the skeletal muscle.Serum ADMA concentration was detected by high performance liquid chromatography.The endogenous ADMA enzymes PRMT1 and 2 subtypes of ADMA me-tabolism enzyme DDAH, 3 subtypes of NOS protein expression in the skeletal muscle were determined by Western blot.NOS activity and nitric oxide ( NO) content were analyzed by colorimetric method.RESULTS: Compared with normal control group, the twitch tension, tetanic tension and the anti-fatigue capability of soleus muscle in running group were significantly enhanced, ATP content, mitochondrial DNA content and the mRNA expression of PGC-1αand NRF were significantly in-creased (P<0.01).In addition, the protein expression of constitute type NOS (cNOS) and NOS activity were significantly increased (P<0.01), but the increase in NO content was relatively smaller in soleus muscle in exercise group (P<0.05). Moreover, serum ADMA concentration in running group was increased, while the DDAH2 expression in skeletal muscle was decreased.CONCLUSION:Short-term endurance exercise enhances the twitch tension, tetanic tension and fatigue resist-
ance of soleus muscle.The mechanism may be that increased cNOS expression feedbacks to increase ADMA concentration, thus maintaining the increase in NO synthesis at a relatively low level, and resulting in promoting skeletal muscle mitochon-dria biosynthesis and mitochondrial function.