Differential sensitivity to Arg side chain modification of IL-1β binding to type I and type II receptors

The central role of interleukin-1 (IL-1) in several disease processes, including fever and inflammation, makes the characterization of ligand-receptor interaction of prime importance.The role of arginine (Arg) side chains of hr-IL-1 in receptor recognition was studied by the modification of Arg residues with the specific reagent 1,2-cyclohexanedione. It was found that chemical modification of Arg residues decreased the binding potential of IL-1 to type I receptor dramatically (by 230-fold) while the affinity to type II receptor was reduced only moderately (by 10-fold), with an insignificant reduction of the dissociation rate.These studies suggest that intact Arg side chains of IL-1 may be necessary for high affinity binding to type I IL-1 receptor, but have less importance for the interaction of IL-1 with type II IL-1 receptor.This observation may be useful in the study of type II IL-1 receptor-mediated biological responses and design of receptor-subtype specific ligands as well.     

Polymorphisms in the human CYP1A1 gene as susceptibility factors for lung cancer: exon-7 mutation (4889 A to G), and a T to C mutation in the 3′-flanking region

Genetic differences in the metabolism of carcinogens may codetermine individual predisposition to cancer. Cytochrome P-4501A1 (CYP1A1) metabolically activates precarcinogens in cigarette smoke, such as benzo(a)pyrene, which is also an inducer of CYP1A1. Two point mutations have been reported, m1 in the 3-flanking region (6235T to C), and m2 within exon 7 (4889A to G), the latter leading to an isoleucine to valine exchange. In the Japanese population ml and m2 are correlated with lung cancer, suggesting an increased susceptibility to cigarette smoking related lung cancer. We studied 142 lung cancer and 171 reference patients in an ethnically homogeneous German group for m1 and m2 mutations by restriction fragment length polymorphism and allele-specific polymerase chain reaction, respectively. No statistically significant difference was found in the distribution of m1 alleles between lung cancer and controls; the frequency was 8.5% and 7.3% of the alleles, respectively (odds ratio = 1.17). A trend to an overrepresentation of ml alleles was observed among 52 squamous cell carcinoma patients (odds ratio = 1.65). In contrast, the frequency of m2 alleles in lung cancer patients was twofold higher (6.7%) than in the reference group (3.2%; odds ratio = 2.16; 95% confidence limits 0.96–5.11, P = 0.033); the odds ratio of m2 alleles in squamous cell carcinoma was 2.51 (95% confidence limits 0.85–7.05, P = 0.05). There was a close genetic linkage of m2 to m1 (10 of 11 reference patients), but a significantly higher number of cancer patients showed no linkage compared to the controls (odds ratio = 8.89, 95% confidence limits 0.83–433, P = 0.04). Thus no association was found between presence of ml alleles and lung cancer, but, in contrast, m2 alleles proved as a hereditary risk factor, especially if not linked with m1 alleles.Abbreviations Ah aryl hydrocarbon - CYP1A1 cytochrome P4501A1 - CYP1A1 CYP1A1 gene - PCR polymerase chain reaction - PY pack years - RFLP restriction fragment length polymorphism Correspondence to: N. Drakoulis     

Psychosis as a predictor of response to lithium maintenance treatment in bipolar affective disorder

Sixty-six bipolar I lithium clinic patients were studied for a history of psychotic symptoms at some time during the course of their illness. Agreement between different sources of information was calculated, and the patient population was divided into psychotic and non-psychotic subgroups. Probability of remaining well on lithium for the different subgroups was analyzed by the life table method. Psychosis during mania appeared to be associated with especially good early lithium prophylaxis.     

Genotypes of autosomal dominant polycystic kidney disease in Japanese

Autosomal dominant polycystic kidney disease (ADPKD) is one of the most common hereditary disorders. The prevalence of the ADPKD genotype in the Caucasian and Latin populations has been reported. Here, we used linkage analysis to demonstrate the prevalence of the genotype and the correlation between phenotypes and genotypes among 21 Japanese ADPKD families consisting of 96 individuals and including 57 affected members. Six polymorphic markers, each linked to either the polycystic kidney disease 1 (PKD1) or polycystic kidney disease 2 (PKD2) gene, were used for polymerase chain reaction analysis. Seventeen families (81%) showed linkage to PKD1, two families (10%) showed linkage to PKD2, and two families did not show linkage to either PKD1 or PKD2. One of the PKD1-linked families was indicated to have different mutations of PKD1 gene in the same family. PKD2-linked families did not have milder symptoms than PKD1-linked families. Received: October 9, 2001 / Accepted: November 9, 2001     

Novel germline BRCA1 and BRCA2 mutations in breast and breast/ovarian cancer families from the Czech Republic

Germline mutations in breast cancer susceptibility genes, BRCA1 and BRCA2, are responsible for a substantial proportion of high‐risk breast and breast/ovarian cancer families. To characterize the spectrum of BRCA1 and BRCA2 mutations, we screened Czech families with breast/ovarian cancer using the non‐radioactive protein truncation test, heteroduplex analysis and direct sequencing. In a group of 100 high‐risk breast and breast/ovarian cancer families, four novel frame shift mutations were identified in BRCA1 and BRCA2 genes. In BRCA1, two novel frame shift mutations were identified as 3761‐3762delGA and 2616‐2617ins10; in BRCA2, two novel frame shift mutations were identified as 5073‐5074delCT and 6866delC. Furthermore, a novel missense substitution M18K in BRCA1 gene in a breast/ovarian cancer family was identified which lies adjacent just upstream of the most highly conserved C3HC4 RING zinc finger motif. To examine the tertiary structure of the RING zinc finger domain and possible effects of M18K substitution on its stability, we used threading techniques according to the crystal structure of RAG1 dimerization domain of the DNA‐binding protein. © 2000 Wiley‐Liss, Inc.     

Macrophage antitumor activity in vitro. Comparative analysis of cytolytic, cytostatic, and cytotoxic activities of mouse macrophages and human monocytes

Mouse peritoneal M phi and human blood monocytes were assayed for their antitumor activity in vitro with a cytolysis, a cytostasis and a cytotoxicity test performed in parallel. Both natural and stimulus-induced M phi antitumor capacities were assessed. Results indicate that natural cytolytic activity of unstimulated M phi is generally unable to restrict final tumor cell growth, since it is not coupled with cytostatic capacity. In contrast, exposure of M phi in vitro to either MAF or IFN-beta, besides augmenting M phi cytolytic capacity, induced a very significant cytostatic activity and thus efficiently restricted the survival of tumor cells.     

Asparate and/or glutamate may be transmitters in hippocampal efferents to septum and hypothalamus

The high affinity uptakes of asparate (Asp) and glutamate (Glu) were heavily and selectively reduced in the lateral septum (?67%) and mammillary body (?52%) by surgical interruption of their connections with the hippocampal formation in rats. There was no reduction in the medial septum. GABA uptake, glutamate decarboxylase, choline acetyltransferase and carnitine acetyltransferase were not reduced. Choline acetyltransferase was increased (+51%) in the lateral septum. The normal activities of these parameters showed characteristic distribution patterns between medial and lateral septum, mammillary body and hippocampus. The ratio of Glu and Asp uptakes was not changed by lesions and vaired only little between the regions sampled.     

In vitro biosynthesis of plasma proteins under ischemic conditions of closed-circuit perfusion of healthy and intoxicated rabbit liver

We are elaborating on the kinetics and mechanisms of septic rabbit liver to de novo biosynthesize acute-phase response (APR) proteins under in vitro conditions of deepening ischemia in reference to their in vivo prevalence in serum and cerebrospinal fluids (CSF) collected at predetermined times. The significance of the data is interpreted as relevant to grafting cadaveric liver into end-stage liver diseased patients and APR-induced ischemic heart diseases (IHD). Hepatic APR was induced by CCl(4)-intubation, and the administration of cholera toxin (CT) or scorpion venom (SV), or both, to rabbits. Hepatic functional efficiency, in terms of biosynthesis of APR proteins in closed circuit perfusion of the isolated intoxicated liver with oxygenated saline or L-15 media paralleled the two-dimensional immunoelectrophoresis (2D-IEP) spectrum of APR serum proteins at time of liver isolation. We are suggesting: (a) in vitro biosynthesis of plasma proteins by isolated perfused liver is the result of in vivo decoded and retained APR inflammatory signals; and (b) decoded inflammatory signals are expressed not withstanding the perfusate's organic composition. Furthermore, 90 min of ischemic perfusion in saline or L-15 medium precipitated mitochondrial aberrations which resulted in further deterioration of de novo biosynthesis of APR plasma proteins. Regardless of the nature of the inflammatory stimuli, mitochondrial aberrations rendered the perfused organ a biologically inert tissue mass that was incapable of resuming biological function upon perfusion with oxygenated L-15 medium. This is most likely due to ischemia-induced irreversible hepatic necrosis. Thus, in vitro aberrations of mitochondrial function(s) critically limit the capability of the isolated liver to resume its organic function to sustain biosynthesis of de novo plasma proteins. Extrapolation of these results to the surgical management of end-stage liver diseases points to the importance of the status and the handling protocol(s) of the cadaver donor liver prior to successful grafting. We conclude that although histology of a cadaver liver may reveal well-preserved hepatic cellular organelles with at least minimal intra- and intercellular communication required for viable hepatic function, we deem it essential to further define acceptable minimal capabilities to de novo biosynthesize plasma proteins by a cadaver liver as a measure of its functional viability and suitability for transplantation. Ultimately, this measure may improve the success of liver transplants with minimal surgical and drug interventions.     

1型糖尿病及肥胖儿童血清瘦素水平及与其它常用指标相关性分析

目的比较1型糖尿病及肥胖儿童血清瘦素水平。方法以EL1SA方法测定35例1型糖尿病、32例肥胖及35例健康儿童的血清瘦素水平。35例1型糖尿病患者中 ,7例为新患糖尿病伴酮症酸中毒的患者。通过测定C -肽水平来评估胰岛素的分泌。C -肽、血糖、糖化血红蛋白按常规方法测定。结果糖尿病患者血清瘦素水平低于对照组 (P<0.001)。肥胖儿童血清瘦素及C -肽水平高于糖尿病组及对照组。在糖尿病新患者中 ,经1个月的胰岛素治疗后 ,血清瘦素水平未有任何变化 (P>0.05)。在联合组中 ,瘦素与体重指数 (bodymassindex,BMI)及C -肽呈正相关(P<0.001) ,而与血糖及糖化血红蛋白呈负相关(P<0.05)。结论1型糖尿病患儿血清瘦素水平低可能与代谢控制有关的慢性胰岛素缺乏引起的。瘦素及胰岛素在保持身体体重稳定的过程中可能起着补充作用。