Fluvastatin alters psychomotor performance and daily activity but not the spatial memory in rats

Statins, inhibitors of cholesterol synthesis for treating dyslipidemia and preventing cardiovascular complications, have been shown to alter central nervous system functions. Our aim was to investigate the effects of the fluvastatin, a member of statin family, on psychomotor performance, daily activity and spatial memory. Sprague-Dawley rats were treated with fluvastatin (n = 8) or placebo as a control (n = 11) regardless of sex. Fluvastatin (7.5 mg/kg) was administered orally once a day for four weeks, while the control group was administered only placebo. Psychomotor performance was measured by rotarod tests. No significant difference was observed in the fluvastatin group over the course of weeks, but the control group preferred to stay on the device shorter times (p < 0.05). For the first three weeks of the drug administration there was a statistical difference between the groups, however no difference was found after the 4th week. There was no difference in the Barnes maze spatial memory test between the groups and also within the groups over the course of time. Daily activity tests revealed that stereotypical and vertical movements of the fluvastatin group were significantly less than the control group in all four weeks. Ambulatory movements and the distances taken by the fluvastatin group were decreased significantly over the course of time (p < 0.005 and p < 0.001, respectively), but the control group did not reveal any significant change. Our results suggest that fluvastatin altered psychomotor performance and daily activity in rats, but it did not affect the spatial memory. These behavioral changes might be associated with alterations in the composition of the brain lipids caused by fluvastatin.     

Human and rat beta cells differ in glucose transporter but not in glucokinase gene expression.

Glucose homeostasis is controlled by a glucose sensor in pancreatic beta-cells. Studies on rodent beta-cells have suggested a role for GLUT2 and glucokinase in this control function and in mechanisms leading to diabetes. Little direct evidence exists so far to implicate these two proteins in glucose recognition by human beta-cells. The present in vitro study investigates the role of glucose transport and phosphorylation in beta-cell preparations from nondiabetic human pancreata. Human beta-cells differ from rodent beta-cells in glucose transporter gene expression (predominantly GLUT1 instead of GLUT2), explaining their low Km (3 mmol/liter) and low VMAX (3 mmol/min per liter) for 3-O-methyl glucose transport. The 100-fold lower GLUT2 abundance in human versus rat beta-cells is associated with a 10-fold slower uptake of alloxan, explaining their resistance to this rodent diabetogenic agent. Human and rat beta-cells exhibit comparable glucokinase expression with similar flux-generating influence on total glucose utilization. These data underline the importance of glucokinase but not of GLUT2 in the glucose sensor of human beta-cells.     

Coagulation-dependent gene expression and liver injury in rats given lipopolysaccharide with ranitidine but not with famotidine

In an animal model of drug idiosyncrasy, rats cotreated with nonhepatotoxic doses of lipopolysaccharide (LPS) and ranitidine (RAN) develop hepatocellular injury, whereas rats treated with LPS and famotidine (FAM) do not. The coagulation system and neutrophils (PMNs) are requisite mediators of LPS/RAN-induced liver injury. We tested the hypothesis that unique gene expression in LPS/RAN-treated rats requires coagulation system activation and that these changes are absent in rats given LPS and FAM. Rats were treated with a nonhepatotoxic dose of LPS (44.4 x 10(6) endotoxin units/kg i.v.) or its vehicle, and then 1 h later, they were treated with heparin (3000 U/kg) or its vehicle. One hour thereafter, they were given RAN (30 mg/kg), FAM (6 mg/kg, a pharmacologically equiefficacious dose, or 28.8 mg/kg, an equimolar dose), or vehicle (i.v.). They were killed 2 or 6 h after drug treatment for evaluation of hepatotoxicity, coagulation system activation, and liver gene expression (2 h only). Statistical filtering of gene array results and real-time polymerase chain reaction identified groups of genes expressed in LPS/RAN-treated rats but not LPS/FAM-treated rats that were either changed or unchanged by heparin administration. For example, LPS/RAN-induced mRNA expression of the inflammatory mediators interleukin-6, cyclooxygenase-2, and macrophage inflammatory protein-2 (MIP-2) was reduced by anticoagulation. Enhancement of serum MIP-2 and plasminogen activator inhibitor-1 concentrations in LPS/RAN-treated rats was prevented by anticoagulation. The results suggest cross-talk between hemostasis-induced gene expression and inflammation (e.g., PMN function) in the genesis of hepatocellular injury in LPS/RAN-treated rats. In contrast, neither the expression of such genes nor hepatocellular necrosis occurred in rats treated with LPS/FAM.     

HBVe抗原的构建及其在肝癌细胞中的表达

目的 构建含有HBV e抗原基因的pcDNA3真核表达载体,并在BEL7402肝癌细胞中表达与鉴定.方法 设计合成针对e基因片段的PCR引物序列,以pUC19/3HBV为模板扩增出HBeAg基因片段,克隆到真核表达载体pcDNA3的多克隆位点中,构建pcDNA-HBeAg真核表达载体.然后采用脂质体转染法将其转染人肝癌细胞系BEL7402肝癌细胞,分别运用逆转录PCR和ELISA在RNA水平和蛋白水平检测其在真核细胞中的表达.结果 所克隆HBV e抗原基因片段经测序完全正确;重组质粒转染BEL7402细胞后,检测有HBeAg表达.结论 成功构建pcDNA3-HBeAg真核表达载体,并在肝癌细胞中有效表达,为进一步体外研究HBeAg奠定基础.     

乙型肝炎病毒PreS1抗原及e抗原表达与血清乙型肝炎病毒DNA表达载量的关系

目的探讨乙型肝炎病毒(HBV)前S1抗原(PreS1-Ag)及HBV e抗原(HBeAg)的表达与产妇血清HBV-DNA载量的关系。方法选取2017年3月至2019年3月于该院诊治的乙型肝炎(简称乙肝)产妇132例作为研究对象,均经临床诊断确诊为HBV感染。采用ELISA检测HBeAg、PreS1-Ag;采用实时荧光定量PCR技术定量检测HBV-DNA;根据HBV-DNA载量分组,比较各组HBeAg、PreS1-Ag检出率,计算HBeAg、PreS1-Ag检测的灵敏度及特异度。结果132例乙肝患者中,HBV-DNA载量<10^3 copy/mL有73例,其中PreS1-Ag阳性39例(53.42%),HBeAg阳性5例(6.85%);HBV-DNA载量在10^3~10^5 copy/mL有21例,其中PreS1-Ag阳性11例(52.38%),HBeAg阳性8例(38.10^%);HBV-DNA载量>10^5~10^8 copy/mL有33例,其中PreS1-Ag阳性29例(87.88%),HBeAg阳性21例(63.64%);HBV-DNA载量>10^8 copy/mL有5例,其中PreS1-Ag和HBeAg的检出率均为10^0.00%。以HBV-DNA载量为10^3 copy/mL为切割值,PreS1-Ag和HBeAg的特异度分别为69.39%、72.34%,灵敏度分别为53.01%、86.84%。结论随着HBV-DNA载量的升高,PreS1-Ag和HBeAg的检出率大幅提高,且PreS1-Ag的诊断灵敏度高于HBeAg;而与PreS1-Ag相比,HBeAg的诊断特异度更高。     

An arginine to histidine mutation in codon 311 of the C-erbA beta gene results in a mutant thyroid hormone receptor that does not mediate a dominant negative phenotype.

We have examined the c-erbA beta thyroid hormone receptor gene in a kindred, G.H., with a member, patient G.H., who had a severe form of selective pituitary resistance to thyroid hormones (PRTH). This patient manifested inappropriately normal thyrotropin-stimulating hormone, markedly elevated serum free thyroxine (T4) and total triiodothyronine (T3), and clinical hyperthyroidism. The complete c-erbA beta 1 coding sequence was examined by a combination of genomic and cDNA cloning for patient G.H. and her unaffected father. A single mutation, a guanine to adenine transition at nucleotide 1,232, was found in one allele of both these members, altering codon 311 from arginine to histidine. In addition, a half-sister of patient G.H. also harbored this mutant allele and, like the father, was clinically normal. The G.H. receptor, synthesized with reticulocyte lysate, had significantly defective T3-binding activity with a Ka of approximately 5 x 10(8) M-1. RNA phenotyping using leukocytes and fibroblasts demonstrated an equal level of expression of wild-type and mutant alleles in patient G.H. and her unaffected father. Finally, the G.H. receptor had no detectable dominant negative activity in a transfection assay. Thus, in contrast to the many other beta-receptor mutants responsible for the generalized form of thyroid hormone resistance, the G.H. receptor appeared unable to antagonize normal receptor function. These results suggest that the arginine at codon 311 in c-erbA beta is crucial for the structural integrity required for dominant negative function. The ARG-311-HIS mutation may contribute to PRTH in patient G.H. by inactivating a beta-receptor allele, but it cannot be the sole cause of the disease.     

Deletion of mu-opioid receptor in mice alters the development of acute neuroinflammation

The realization that the mu-opioid system plays a key role in the control of the process of neuroinflammation is a new concept that may lead to identification of novel therapies for this extremely widespread and intractable syndrome. Fever is the hallmark among the defense mechanisms evoked by the entry into the body of pathogens to initiate the innate immune responses. In an attempt to determine the possible involvement of mu-opioid receptors in the control of brain inflammation, we examined the effect of their deletion on the fever induced by i.c.v. injection of lipopolysaccharide (LPS). The first series of experiments examined the thermal consequence of the absence of mu-opioid receptors on circadian body temperature rhythm and basal body temperature. Mu-opioid receptor knockout mice (MOP-KO) showed a normal circadian body temperature rhythm and basal body temperature compared with the wild type (WT). The second series of experiments investigated i.c.v. administration of LPS on body temperature in WT and MOP-KO. In the WT, i.c.v. injection of 100 ng of LPS induced fever, but there was no increase in body temperature in the MOP-KO mice. Saline, given i.c.v., did not alter the body temperature, either in WT or MOP-KO. These results show that the mu-opioid system participates in the control of acute neuroinflammation, further reinforcing our earlier finding that the opioid system is involved in the pathogenesis of fever induced by bacterial LPS, and that mu-opioid receptors are the target for morphine-induced hyperthermia.     

Deletion of the nucleotide excision repair gene Ercc1 reduces immunoglobulin class switching and alters mutations near switch recombination junctions

The structure-specific endonuclease ERCC1-XPF is an essential component of the nucleotide excision DNA repair pathway. ERCC1-XPF nicks double-stranded DNA immediately adjacent to 3' single-strand regions. Substrates include DNA bubbles and flaps. Furthermore, ERCC1 interacts with Msh2, a mismatch repair (MMR) protein involved in class switch recombination (CSR). Therefore, ERCC1-XPF has abilities that might be useful for antibody CSR. We tested whether ERCC1 is involved in CSR and found that Ercc1(-)(/)(-) splenic B cells show moderately reduced CSR in vitro, demonstrating that ERCC1-XPF participates in, but is not required for, CSR. To investigate the role of ERCC1 in CSR, the nucleotide sequences of switch (S) regions were determined. The mutation frequency in germline Smicro segments and recombined Smicro-Sgamma3 segments cloned from Ercc1(-)(/)(-) splenic B cells induced to switch in culture was identical to that of wild-type (WT) littermates. However, Ercc1(-)(/)(-) cells show increased targeting of the mutations to G:C bp in RGYW/WRCY hotspots and mutations occur at sites more distant from the S-S junctions compared with WT mice. The results indicate that ERCC1 is not epistatic with MMR and suggest that ERCC1 might be involved in processing or repair of DNA lesions in S regions during CSR.     

Transgene expression, but not gene delivery, is improved by adhesion-assisted lipofection of hematopoietic cells.

In contrast to adherent cells, cells growing in suspension and particularly hematopoietic cells, are notoriously difficult to transfect in vitro using nonviral approaches. In the present study, the effect of cell adhesion on gene transfer efficacy was investigated by allowing hematopoietic cells to bind to an adherent cell monolayer (ACM) before being subjected to cationic liposome-mediated DNA transfer. Human CD34 and T CD4 cell lines were cultivated on an ACM constituted of murine fibroblast NIH3T3 cells and transfected with a plasmid carrying the beta-galactosidase gene. X-gal staining showed that up to 27% of the cells expressed the transgene. In contrast, less than 0.1% of these cells were positively transfected in suspension. This adhesion-assisted lipofection (AAL) procedure was also successfully tested on blood lymphocytes, since it resulted in up to 30% of transfected human primary T lymphocytes. Flow cytometry analysis performed on T lymphocyte subsets revealed that 8 and 9%, respectively, of CD4 and CD8 cells could be transfected with a plasmid carrying the green fluorescent protein gene. Other adherent cells, such as MS5 murine stromal cells or HeLa epithelial cells, were also a compatible matrix for AAL. Moreover, the pCMV beta plasmid was present in similar amounts in the nuclei of TF1 cells transfected in suspension or with the AAL procedure. These data raise the possibility that cell matrix/hematopoietic cell interactions might govern expression of the transgene in hematopoietic cells growing usually in suspension, but not endocytosis of liposome/DNA particles and plasmid migration ot the cell nucleus.     

Recreational and master athletic activity does not affect free and total prostate-specific antigen levels but lowers the free-to-total prostate-specific antigen ratio

Prostate-specific antigen (PSA) and the ratio of free-to-total PSA are widely used tumour markers, but the effect of exercise on these parameters is unclear. We aimed to determine whether long-term physical training was associated with changes in serum PSA by comparing PSA concentrations in middle-aged master athletes (n = 12), recreational athletes (n = 12) and sedentary controls (n = 12). Serum total PSA and free PSA concentrations were assessed using an electrochemiluminescence immunoassay; there were no significant differences among the groups. The free-to-total PSA ratio was significantly lower statistically in master athletes compared with recreational athletes, but this is not clinically significant as both values (0.22 versus 0.31, respectively) were within the normal range. These results indicate that the free-to-total PSA ratio may be affected by long-term athletic training, and could be important when evaluating athletes with prostate-related disorders.     

Deeper 'Go' phase in rat fibroblasts affects the lag time required for T antigen induced DNA synthesis, but not the lag time required for SV40 T antigen expression

In density-arrested rat 3YltsG125 cells, the time required for entry into S phase after serum stimulation is prolonged with increase in duration of the arrest. When these cells were infected with simian virus 40, the time required for expression of T antigen did not change, but the time required for entry into S phase was prolonged with increase in duration of the arrest. The extent of prolongation of the interval between T antigen expression and entry into S phase correlated well with the extent of the prolongation detected with serum stimulation. These observations suggest that: (1) expression of T antigen was not affected by the level of cellular preparedness for entry into S phase, i.e., it did not depend on cellular functions directly involved in the preparedness, and (2) T antigen induced cellular DNA synthesis, at least in part, by a mechanism similar to that of serum-induced DNA synthesis.     

Analysis of the expression of neutrophil-specific antigen NB1: characterization of neutrophils that react with but are not agglutinated by anti-NB1

The neutrophil-specific NB antigen system has been serologically characterized with human alloantisera. Two alleles, NB1 and NB2, have been described. NB1 is expressed on a subpopulation of peripheral blood neutrophils in 97 percent of healthy donors. Human alloantibodies have been used to identify the 58- to 64-kDa glycoprotein (GP) on which NB1 is located. NB1 can usually be detected by both a granulocyte immunofluorescence (GIF) assay and a granulocyte agglutination (GA) assay, but neutrophils from some donors have been found to react with anti-NB1 in GIF but not in GA assays. To determine if the latter neutrophils express NB1 and the corresponding 58- to 64-kDa GP, these neutrophils were probed with rabbit and human sera specific for NB1. First, the proportion of neutrophils that express NB1 was quantitated. Neutrophils from donors that typed as NB1-positive in both GA and GIF assays were analyzed by flow cytometry with antisera to NB1. Human and rabbit anti-NB1 reacted with 71 +/− 17 percent and 70 +/− 17 percent of neutrophils, respectively. There was no difference in the expression of NB1 in NB1-homozygous and NB1-heterozygous individuals. In contrast, significantly fewer neutrophils from four donors that typed as NB1- positive in GIF assay but not GA assay reacted with human (27 +/− 12%; p < 0.001) and rabbit (26 +/− 12%; p < 0.001) anti-NB1. When neutrophils from these same four donors were probed with rabbit and human anti-NB1 by immunoblotting and immunoprecipitation, the 58- to 64- kDa GP was identified.(ABSTRACT TRUNCATED AT 250 WORDS)     

Deletion of the fyn-kinase gene alters sensitivity to GABAergic drugs: dependence on beta2/beta3 GABAA receptor subunits

Tyrosine phosphorylation can modulate GABA(A) receptor function, and deletion of the fyn-kinase gene alters GABAergic function in olfactory bulb neurons, as reported by Kitazawa, Yagi, Miyakawa, Niki, and Kawai (J Neurophysiol 1998;79:137-142). Our goal was to determine whether fyn gene deletion altered behavioral and functional actions of compounds that act on GABA(A) receptors. Such evidence might suggest a role for fyn-kinase in modulating GABA(A) receptor function, possibly via direct interactions between the kinase and receptor. Using the loss of righting reflex test, we found that null mutants were less sensitive to the hypnotic effects of THIP (4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol), a GABA(A) receptor agonist. Subunit specificity was suggested by the observation that null mutants were also less sensitive to the hypnotic effects of etomidate, a GABAergic compound that is selective for receptors possessing beta2 and/or beta3 receptor subunits. The genotypes did not differ in sensitivity to zolpidem, an alpha1-selective GABAergic drug. GABA(A) receptor functional assays ((36)Cl(-) influx) supported our behavioral results; the actions of the GABA(A) agonists, THIP and muscimol, were reduced in the cerebellar membranes of fyn-null mutant mice. Importantly, similar results were seen with etomidate. Binding of [(3)H]flunitrazepam supported the idea that this is due to a decrease in functional GABA(A) receptor density. These data suggest that fyn-kinase may alter the function of GABA(A) receptors, perhaps via actions on beta2 and/or beta3 receptor subunits.     

Kirsten murine sarcoma virus abolishes interferon gamma-induced class II but not class I major histocompatibility antigen expression in a murine fibroblast line

The effect of infecting fibroblasts with Kirsten murine sarcoma virus/murine leukemia virus (Ki-MSV/MLV) on constitutive and IFN-gamma-induced H-2 antigen expression was investigated. The fibroblasts used were two established cell lines (C3H10T1/2 and BALB/c3T3) and fresh embryo fibroblasts from C3H mice. Class I antigens were expressed constitutively by BALB/c3T3; infection with MLV, MSV or the two together had little effect on this constitutive expression. Class I antigens (H-2K, H-2D) were strongly induced on all three types of fibroblast by rIFN-gamma, and infection had little effect on this. None of the fibroblasts expressed constitutively detectable levels of class II antigen; however, C3H10T1/2 fibroblasts could be induced for both H-2A and H-2E by IFN-gamma. Infection of C3H10T1/2 with helper-free Ki-MSV, or MSV together with MLV, completely abolished this induction of class II antigens, while infection with MLV alone had little effect, implying that the abolition of class II induction was due to genomic regions of Ki-MSV not shared with Ki-MLV, probably the v-Ki-ras gene.