Factors affecting the infection of the D variant of encephalomyocarditis virus in the B cells of C57BL/6J mice

Summary The D variant of encephalomyocarditis viras is capable of infecting most inbred strains of mice. However, only certain strains are susceptible to the diabetogenic effect of this viras. In order to understand why some inbred strains do not become diabetic, the pathogenesis of infection was studied in diabetes-resistant C57BL/6J mice. It was the purpose of the investigation to ascertain whether specific host defense factors might play a crucial role in the mechanism of resistance. To determine whether perturbations of the immune response would alter the resistance of these animals, mice were treated with a high dose (1.15 mmol/kg body weight) of the T- and B-cell toxin cyclophosphamide prior to infection with the D variant. This treatment did not induce overt diabetes or glucose intolerance in the mice tested 7 days after infection. Based on this finding, it appeared likely that resistance to the D variant is conveyed by some factor other than cell-mediated immunity. A likely candidate to control this viral infection is the interferon system. To investigate this possibility, C57BL/6J mice were infected with the D variant and the concentrations of serum interferon titred at various intervals thereafter. In contrast to previous reports with diabetes susceptible mice, C57BL/6J mice were found to generate a substantial interferon response against this variant, with peak levels found in the serum at 24 h following infection. Additional studies were performed in which mice were treated with antibody to mouse interferon alpha/beta at the time of infection and again 3 days after infection with the D variant. Sixty percent of the animals treated in this manner became glucose intolerant. The results of these studies indicate that the interferon system is a critical determinant of resistance to the diabetogenic effect of the D variant in C57BL/6J mice.     

Age and Sex Influences on Airway Hyperresponsiveness

Objective. The precise relationship between age and gender and their influence on airway reactivity has not been clearly defined. Previous studies of age and gender influences on airway reactivity have been confounded by environmental influences such as cigarette smoking. The objective of this study was to examine the effect of age and gender on airway reactivity in C57BL/6 mice housed under controlled conditions, independent of confounding environmental factors. Methods. Mice were separated into four experimental groups based on age and gender: males at 6 and 12 weeks of age and females at 6 and 12 weeks of age. Airway reactivity to inhaled methacholine was examined in each group. Results. Significant differences in methacholine-induced airway reactivity were observed between the sexes at both age groups. At 6 weeks of age, the males demonstrated a significantly increased airway reactivity to methacholine as compared to females (p <.001). Paradoxically, at 12 weeks of age, the males demonstrated a significantly lower response to methacholine as compared to females (p <.001). Hence the relationship between age and airway reactivity is markedly different in males as compared to females. Examination of intragender differences revealed that in female mice, airway reactivity increased significantly with age (p <.001). In contrast, males demonstrated a significant reduction in airway reactivity with age (p <.001). Conclusion. These findings demonstrate important differences in airway reactivity related to age and gender that are observed independent of any environmental influences. Furthermore, these findings highlight the importance of careful age and sex matching in studies of airway reactivity.     

Transient Neonatal Diabetes Mellitus in a Turkish Patient with Three Novel Homozygous Variants in the ZFP57 Gene

Neonatal diabetes mellitus (NDM) is a rare form of diabetes that presents within the first six months of life. Nearly 70% of these cases have loss of methylation at the differentially methylated region on chromosome 6q24. To describe the findings in a Turkish male patient with NDM caused by a loss of methylation at chromosome 6q24 and three novel homozygous mutations in the ZFP57 gene, methylation-specific PCR was carried out at 6q24 and mutation analysis of ZFP57 gene was maintained by direct sequencing. Sequencing of ZFP57 gene revealed the hypomethylation of chromosome 6q24 and three novel mutations (chr6:29.641.413 A>T, 29.641.073 C>T, and 29.640.855 G>C), respectively. The latter mutation seems to display the patient’s condition due to a highly conservative amino acid substitution in the protein. We suggest the ZFP57 gene as a causative factor for NDM and it should be considered in genetic testing. Further studies including functional analysis of the detected mutations will provide precise information regarding the effect of the mutations.Conflict of interest:None declared.     

Discriminative stimulus effects of ethanol in C57BL/6J and DBA/2J inbred mice

BACKGROUND: Two of the most widely used mouse strains for studying the behavioral effects of ethanol are C57BL/6J (B6) and DBA/2J (D2) mice. These strains exhibit marked differences in behavioral and physiological responses to ethanol. The subjective discriminative stimulus effects of ethanol may play a role in ethanol abuse, but the discriminative stimulus profile of ethanol has not been compared in B6 and D2 mice. Examination of the discriminative stimulus effects of ethanol in B6 and D2 mouse strains may enhance our understanding of the relationship between the subjective effects of ethanol and other ethanol-induced behavioral effects. METHODS: Twelve adult male C57BL/6J mice and 12 male DBA/2J mice were trained to discriminate 1.5 g/kg ethanol from saline in daily 15 min, milk-reinforced operant sessions. After training, ethanol substitution and response-rate suppression dose response curves were determined for ethanol, midazolam, diazepam, pentobarbital, pregnanolone, 4,5,6,7-Tetrahydroisoxazolo[5,4-c]pyridin-3-ol (THIP), dizocilpine, and morphine. RESULTS: D2 mice learned the ethanol discrimination significantly more quickly than did B6 mice. Ethanol, midazolam, pregnanolone, and dizocilpine fully substituted for ethanol in both strains. Pentobarbital was more potent in producing ethanol-like discriminative stimulus effects in D2 than B6 mice. Midazolam and diazepam were significantly more potent in suppressing response rates in D2 than B6 mice. Morphine failed to substitute for ethanol in either strain, but the ED50 for morphine suppression of responding was significantly lower in B6 than D2 mice. CONCLUSIONS: The initial stimulus effects of 1.5 g/kg ethanol may be more salient in D2 than B6 mice. This does not appear to result from differences in the neurotransmitter systems that mediate ethanol's discriminative stimulus effects. In both strains, gamma-aminobutyric acid-positive modulators and a noncompetitive NMDA antagonist substituted for ethanol. However, strain differences did exist in the potency of gamma-aminobutyric acid-positive modulators and morphine for suppressing operant responding.     

Molecular and flow cytometric characterization of the CD4 and CD8 T-cell repertoire in patients with myelodysplastic syndrome

We studied 18 patients with myelodysplastic syndrome (MDS), measuring clonality and T-cell receptor Vbeta (TCRBV) expression of CD4 and CD8 T cells by polymerase chain reaction and by flow cytometric analysis of TCRBV families. The CD4 and CD8 T-cell repertoire in most MDS patients is characterized by an abnormal TCRBV-restricted expansion of T cells in CD4 and CD8 cells, and increased expression of the CD8 effector marker CD57 of multiple TCRBV in CD8 cells. Clonality analysis of CD4 and CD8 cells showed that seven of 10 patients analysed had a major clone in the CD8 cells but not in CD4 cells. Furthermore, in one patient we found that both the CD57- and CD57+ fraction contained the clone (which was absent from the TCRBV-negative fraction). These data suggest that, in MDS, multiple T-cell expansions can be found in both helper and cytotoxic T cells, and that, in the CD8 cells, T cells functionally differentiate in vivo from memory to effector T cells. Together, these data support the hypothesis of the involvement of T cells in the pathogenesis of MDS.     

Ethanol‐Induced Increase of Agouti‐Related Protein (AgRP) Immunoreactivity in the Arcuate Nucleus of the Hypothalamus of C57BL/6J,but not 129/SvJ,Inbred Mice

Background: The melanocortin (MC) system is composed of peptides that are cleaved from the polypeptide precursor, pro‐opiomelanocortin (POMC). Previous research has shown that MC receptor (MCR) agonists reduce, and MCR antagonists increase, ethanol consumption in rats and mice. Consistently, genetic deletion of the endogenous MCR antagonist, agouti‐related protein (AgRP), causes reductions of ethanol‐reinforced lever pressing and binge‐like ethanol drinking in C57BL/6J mice. Ethanol also has direct effects on the central MC system, as chronic exposure to an ethanol‐containing diet causes significant reductions of α‐melanocyte stimulating hormone (α‐MSH) immunoreactivity in specific brain regions of Sprague‐Dawley rats. Together, these observations suggest that the central MC system modulates neurobiological responses to ethanol. To further characterize the role of the MC system in responses to ethanol, here we compared AgRP and α‐MSH immunoreactivity in response to an acute injection of saline or ethanol between high ethanol drinking C57BL/6J mice and moderate ethanol drinking 129/SvJ mice. Methods: Mice received an intraperitoneal (i.p.) injection of ethanol (1.5 g/kg or 3.5 g/kg; mixed in 0.9% saline) or an equivolume of 0.9% saline. Two hours after injection, animals were sacrificed and their brains were processed for AgRP and α‐MSH immunoreactivity. Results: Results indicated that acute ethanol administration triggered a dose‐dependent increase in AgRP immunoreactivity in the arcuate (ARC) of C57BL/6J mice, an effect that was not evident in the 129/SvJ strain. Although acute administration of ethanol did not influence α‐MSH immunoreactivity, C57BL/6J mice had significantly greater overall α‐MSH immunoreactivity in the ARC, dorsomedial, and lateral regions of the hypothalamus relative to the 129/SvJ strain. In contrast, C57BL/6J mice displayed significantly lower α‐MSH immunoreactivity in the medial amygdala. Conclusions: The results show that acute ethanol exposure has direct effects on endogenous AgRP activity in ethanol preferring C57BL/6J mice. It is suggested that ethanol‐induced increases in AgRP may be part of a positive feedback system that stimulates excessive binge‐like ethanol drinking in C57BL/6J mice. Inherent differences in α‐MSH immunoreactivity may contribute to differences in neurobiological responses to ethanol that are characteristically observed between the C57BL/6J and 129/SvJ inbred strains of mice.     

p57kip2蛋白和增殖细胞核抗原在胰腺癌组织中的表达及其临床意义探讨

目的　探讨细胞周期调控抑制因子 p5 7kip2 蛋白和增殖细胞核抗原 (PCNA)表达在胰腺癌发生发展中的作用及其临床意义。方法　采用免疫组织化学技术SP法 ,检测p5 7kip2 和PC NA在 32例胰腺癌组织和癌旁胰腺组织中的表达情况。结果　p5 7kip2 蛋白阳性表达率在胰腺癌组织中为 46 9% ,显著低于癌旁胰腺组织 (P <0 0 5 ) ,并与胰腺癌组织分化程度有关 (P <0 0 5 )而与淋巴结转移无关 ( χ2 =3 698,P >0 0 5 ) ;PCNA蛋白阳性表达率在胰腺癌组织中为71 9% ,显著高于癌旁胰腺组织 (P <0 0 5 ) ,并与胰腺癌组织分化程度和淋巴结转移均有关 (P<0 0 5 )。结论　p5 7kip2 、PCNA可能与胰腺癌发生、发展密切相关 ;p5 7kip2 蛋白表达降低、PCNA蛋白过度表达有助于胰腺癌的发生及细胞分化程度及预后的判定 ,但 p5 7kip2 蛋白低表达与胰腺癌淋巴结转移无关     

大肠腺癌p57kip2和cyclin E蛋白表达及与临床病理关系研究

目的　探讨细胞周期调控抑制因子p5 7kip2 蛋白和cyclinE(周期蛋白E)在大肠腺癌发生发展中的作用。方法　采用免疫组化技术SP法 ,检测p5 7kip2 和cyclinE蛋白在 3 7例大肠腺癌和 2 6例正常大肠粘膜组织中的表达。结果　p5 7kip2 蛋白阳性表达率在大肠腺癌组织中为 40 5 % ,显著低于正常大肠粘膜组织 ( χ2 =5 0 3 9,P <0 0 5 ) ,并与大肠腺癌组织分化程度和淋巴结转移均有关 ( χ2 =8 914 ,χ2 =4 416,P <0 0 5 ) ;cyclinE蛋白阳性表达率在大肠腺癌组织中为 64 9% ,显著高于正常大肠粘膜组织 ( χ2 =4 2 85 ,P <0 0 5 ) ,并与大肠腺癌组织分化程度和淋巴结转移均有关 ( χ2 =8 3 97,χ2 =5 2 61,P <0 0 5 ) ;p5 7kip2 蛋白阳性表达组cyclinE蛋白阳性表达率低于p5 7kip2 蛋白阴性表达组 ,但两者之间呈负相关 ( r=-0 3 0 2 7,P <0 0 5 )。结论　p5 7kip2 蛋白的低表达和 (或 )cyclinE蛋白的高表达可能在大肠腺癌发生发展中发挥重要作用 ;p5 7kip2 和cyclinE蛋白在大肠腺癌细胞周期调控中可能存在着负反馈调节机制     

Spirometric criteria for airway obstruction: Use percentage of FEV1/FVC ratio below the fifth percentile, not < 70%

BACKGROUND: Current authoritative spirometry guidelines use conflicting percentage of FEV1/FVC ratios (FEV1/FVC%) to define airway obstruction. The American Thoracic Society/European Respiratory Society Task Force characterizes obstruction as a FEV1/FVC% below the statistically defined fifth percentile of normal. However, many recent publications continue to use the Global Initiative for Chronic Obstructive Lung Disease (GOLD) primary criterion that defines obstruction as a FEV1/FVC% < 70%. Data from the Third National Health and Nutrition Examination Survey (NHANES-III) should identify and quantify differences, help resolve this conflict, and reduce inappropriate medical and public health decisions resulting from misidentification. METHODS: Using these two guidelines, individual values of FEV1/FVC% were compared by decades in 5,906 healthy never-smoking adults and 3,497 current-smokers of black (African American), Hispanic (Latin), or white ethnicities aged 20.0 to 79.9 years. RESULTS: In the never-smoking population, the lower limits of normal used in other reference equations fit reasonably well the NHANES-III statistically defined fifth percentile guidelines. But nearly one half of young adults with FEV1/FVC% below the NHANES-III fifth percentile of normal were misidentified as normal because their FEV1/FVC% was > 70% (abnormals misidentified as normal). Approximately one fifth of older adults with observed FEV1/FVC% above the NHANES-III fifth percentile had FEV1/FVC% ratios < 70% (normals misidentified as abnormal). CONCLUSIONS: The GOLD guidelines misidentify nearly one half of abnormal younger adults as normal and misidentify approximately one fifth of normal older adults as abnormal.