Cerivastatin inhibits fetal calf serunvinduced DNA synthesis in cultured rat mesangial cells

SUMMARY: Inhibition of mevalonate synthesis by several statins has been shown to suppress DNA synthesis in glomerular mesangial cells. In the present study, we investigated the effect of a new statin, cerivastatin, on fetal calf serum (FCS)-induced DNA synthesis of cultured rat mesangial cells. Cultured rat mesangial cells were stimulated by 10% FCS in the presence or absence of cerivastatin and mevalonate. 5-bromo-2-deoxyuridine (BrdU) incorporation was used to assess DNA synthesis. the present study showed that 10% FCS caused marked stimulation of DNA synthesis in the mesangial cells. Cerivastatin inhibited FCS-stimulated BrdU incorporation in a dose-dependent manner. IC₅₀ was approximately 1 umol/L. Exogenous mevalonate, farnesyl pyrophosphate and geranylgeranyl pyrophosphate significantly prevented the inhibitory effect of cerivastatin on DNA replication. It appears that cerivastatin, by inhibiting the synthesis of mevalonate, may suppress DNA synthesis in the mesangial cells.     

Genetic susceptibility to type 2 diabetic nephropathy in human and animal models

SUMMARY:   Diabetic nephropathy is the most common cause of end-stage renal disease (ESRD) in Japan, Western Europe, and the United States. Mega studies such as Diabetes Control and Complication Trial (DCCT), Epidemiology of Diabetes Interventions and Complications (EDIC), and the United Kingdom Prospective Diabetes Study (UKPDS) clarified that poor glycemic and blood pressure control are undoubtedly involved in the development of nephropathy. However, these factors are not sufficient to predict which diabetic patients will develop renal disease, because not all patients with poor glycemic and blood pressure control develop renal disease. Since ethnic variations and familial clustering of diabetic nephropathy have been observed, genetic factors might contribute to susceptibility to this disease. Several methods such as (genome wide) association studies, sib-pair analysis, and quantitative trait loci (QTLs) analysis are available to examine polygenic diseases. However, no mutations that could explain the majority of nephropathy cases have been identified so far. The development of most diabetic nephropathy might be explained by the polygenic effect (i.e. many minor gene-gene interactions might be very important in the development of nephropathy). Identification of candidate genes of nephropathy enables targeting of therapy in patients at risk and development of novel therapeutic agents.     

Pharmacokinetic Analysis of Increased Toxicity of 2-sec-Butylphenyl Methylcarbamate (BPMC) by Fenitrothion Pretreatment in Mice

Pharmacokinetk Analysis of Increased Toxicity of 2-sec-ButylphenylMethylcarbamate (BPMC) by Fenitrothion Pretreatment in Mice.TSUDA, S., MIYAOKA, T., IWASAKI, M., AND SHIRASU, Y. (1984).Fundam. Appl. Toxicol. 4, 724–730. The potentiating effectof O,O-dimethyl O-(3-methyl-4-nitrophenyl) phosphorothioate(fenitrothion) on the toxicity of 2-sec-butylphenyl methylcarbamate(BPMC) in male mice was analyzed pharmacokinetically. The animalspretreated by dietary administration of 1000 ppm fenitrothionfor 1 week (4.4% of the po LD50 daily) did not show toxic symptomsexcept for a slight decrease in body weight In the fenitrothion-pretreatedmice, toxicity of fenitrothion was not changed but a fivefoldpotentiation was observed in po and ip acute lethality and athreefold potentiation of iv lethality of BPMC. Toxic signsafter BPMC administration were similar regardless of fenitrothionpretreatment or of route of administration. Fenitrothion pretreatmentfollowed by BPMC administration (20 mg/kg po or 8 mg/kg iv,approximate LD5 in the pretreated mice) significantly increasedthe plasma BPMC concentration and the total area under the plasmaconcentration versus time curve (AUG_0-. The pretreatment increasedthe oral AUC_0-, more greatly than the iv AUC_0-, (for po, 6.3-fold;for iv, 2.0-fold). The oral systemic availability of BPMC (fractionreaching systemic circulation) was increased by fenitrothiontreatment to 3.3-fold. These results suggest that a major causeof the potentiation may be the increase in amount of BPMC inthe systemic circulation.     

HLA-DR ALLELES IN PATIENTS WITH SJOGREN'S SYNDROME OVER-REPRESENTING V{beta}2 AND V{beta}13 GENES IN THE LABIAL SALIVARY GLANDS

To identify genetic factors that play a role in the pathogenesisof patients with SS over-representing Vß2 and Vß13genes in the lips, HLA-DR and -DQ alleles of 10 primary SS patientswith predominant expression of Vß2 and Vß13genes in the lips were analysed, using the polymerase chainreaction (PCR) and sequence specific oligonucleotide probes.The CDR3 amino acid sequences of cDNA clones encoding Vß2and Vß3 genes were also determined by PCR. The resultsshowed that the DRB4^*0101 allele was significantly increased(80%) and that the frequency of DRB3 allele was decreased (0%)when compared to findings in healthy subjects (35.6 and 26%,respectively). Sequencing analyses demonstrated that 75% ofVß2 cDNA clones and 87% of Vß13 cDNA cloneshad a glutamine residue at position 106, in the CDR13 region.Moreover, the conserved sequences (Y^*TLRNEQ) in the CDR3 ofVß13-positive T cell were detected in two differentclones (27%) from the two individual SS patients. These findingssuggest that the decreased DRB3 and increased DRB4^*0101 allelesmay be associated with the antigens recognized by Vß2-and Vß13-positive T cells. KEY WORDS: HLA, Sjögren's syndrome, TCR Vß, CDR3 region     

Differences in the Mode of Lethality Produced through Intravenous and Oral Administration of Organophosphorus Insecticides in Rats

Differences in the Mode of Lethality Produced through Intravenousand Oral Administration of Organophosphorus Insecticides inRats. TAKAHASHI, H., KOJIMA, T., IKEDA, T., TSUDA, S. and SHIRASU,Y. (1991). Fundam. Appl. Toxicol. 16, 459–468. This studywas undertaken to investigate the possibility that mechanismsother than cholinesterase (ChE) inhibition account for the acutetoxicity of organophosphorus insecticide. Both the PO type insecticide(direct ChE inhibitors: chlorfenvinphos and dichlorvos) andthe PS type insecticide (indirect ChE inhibitors: diazinon andfenthion) were employed. Rats treated with lethal doses of intravenousand oral PO type insecticides and oral PS type insecticidesexhibited typical signs of anti-ChE poisoning along with markedinhibition of brain and erythrocyte ChE activity. In contrast,rats given lethal doses of intravenous PS type insecticidesexhibited tonic convulsions and opisthotonos, with only slightinhibition of ChE activities. When PO type insecticides wereintravenously administered to anesthetized and conscious rats,animals exhibited typical anti-ChE poisoning signs in cardiorespiration:hypertension and apnea which were antagonized by atropine. Afteradministration of lethal doses of PO type insecticides, breathingdisappeared before the cessation of heart beats. Rats receivinglethal doses of intravenous PS type insecticides did not showhypertension, but exhibited transient cessation of breathingand heart beats. Breathing was observed after the disappearanceof heart beats. The electroencephalogram (EEG) was characterizedby spike and wave complexes. The EEG and cardiorespiratory changeswere not antagonized by atropine. It was concluded that lethalityfollowing intravenous PS type insecticides may be independentof ChE inhibition.     

英卡膦酸盐对佐剂关节炎模型大鼠骨与关节的影响

目的:研究英卡膦酸盐对佐剂关节炎大鼠的关节炎症、肿胀以及结构破坏的影响.方法:35只雌性Lewis大白鼠随机分为5组:正常对照组、模型组和英卡膦酸盐低、中、高剂量组,每组7只.除正常对照组外,其余4组接种佛氏完全佐剂诱发关节炎.英卡膦酸盐3个剂量组自接种之日起,连续42 d皮下注射英卡膦酸盐0.01,0.1和1 mg·kg-1·d-1,qd.记录关节炎分数,测定后足肿胀程度,并观察大鼠后肢放射学和踝关节组织病理学变化.结果:与模型组比较,英卡膦酸盐剂量依赖性地降低关节炎分数和后足肿胀程度;大鼠后肢放射学和踝关节组织病理学变化显示,英卡膦酸盐减轻踝与足部骨、关节的变形破坏,X线分数和TRAP阳性细胞计数剂量依赖性的降低.结论:英卡膦酸盐对大鼠佐剂关节炎的关节炎症、肿胀以及结构破坏具有抑制作用,提示英卡膦酸盐可作为类风湿性关节炎的辅助预防治疗药物.     

Comparative study of the stability of the folding intermediates of the calcium-binding lysozymes

Unfolding profiles of two calcium-binding lysozymes, equine milk lysozyme and pigeon egg-white lysozyme, were obtained by circular dichroism and proton NMR measurements. Equine lysozyme unfolds through a stable molten globule intermediate. The molten globule of equine lysozyme was characterized as more ordered than that of bovine α-lactalbumin. On the other hand, pigeon lysozyme unfolds by a two-state mechanism and the intermediate could not be observed in guanidine or thermal unfolding, the same as with conventional non-calcium-binding lysozymes. Thus, from the point of view of the unfolding profile, equine lysozyme belongs to the group of α-lactalbumin, but pigeon lysozyme belongs to the conventional lysozyme group.     

Hepatic encephalopathy due to a large intrahepatic communication between the portal vein and inferior vena cava

A 59 year old man with cirrhosis presented with encephalopathy and hyper-ammonaemia. T1 weighted magnetic resonance imaging demonstrated a large void tubular structure connecting the right posterior portal vein branch and the inferior vena cava through the right hepatic lobe inferiorly, and cine-mode imaging showed a flow within this channel. Clearly in this patient a significant portion of the portal venous blood was being shunted into the inferior vena cava, causing encephalopathy. The exact origin of this channel is not known, but several possibilities are discussed. It is also predicted that similar previously unknown large intrahepatic shunts will be discovered increasingly with the availability of modern imaging techniques.     

VDD Pacing with a Previously Implanted Single Lead System

Three patients who had undergone implantation of a rate modulated, afrial sensitive RS4 pacemaker, with a single orthogonal lead underwent replacement of a depleted unit with a DDD pulse generator, reusing the original lead with an adapter that allowed conversion of the bipolar atrial electrode into unipolar configuration. The mean atrial electrogram amplitude was 1,8 mV and no significant atrial sensing defects were found during Holler monitoring. As the RS4 pulse generator is no longer available, continued VDD pacing is possible by replacing it with a DDD pulse generator using the previously implanted single lead system.