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The intestinal epithelium is a paradigm of adult tissue in constant regeneration that is supported by intestinal stem cells (ISCs). The mechanisms regulating ISC homeostasis after injury are poorly understood. We previously demonstrated that IκBα, the main regulator of NF‐κB, exerts alternative nuclear functions as cytokine sensor in a subset of PRC2‐regulated genes. Here, we show that nuclear IκBα is present in the ISC compartment. Mice deficient for IκBα show altered intestinal cell differentiation with persistence of a fetal‐like ISC phenotype, associated with aberrant PRC2 activity at specific loci. Moreover, IκBα‐deficient intestinal cells produce morphologically aberrant organoids carrying a PRC2‐dependent fetal‐like transcriptional signature. DSS treatment, which induces acute damage in the colonic epithelium of mice, results in a temporary loss of nuclear P‐IκBα and its subsequent accumulation in early CD44‐positive regenerating areas. Importantly, IκBα‐deficient mice show higher resistance to damage, likely due to the persistent fetal‐like ISC phenotype. These results highlight intestinal IκBα as a chromatin sensor of inflammation in the ISC compartment. Synopsis: IκBα resides in the nucleus of intestinal stem cells and its deficiency leads to aberrant PRC2 activity, a fetal‐like ISC phenotype and defective differentiation. IκBα‐deficient mice show resistance to intestinal damage, likely due to their fetal‐like ISCs. Intestinal crypt cells contain nuclear SUMOylated IκBα.IκBα deficiency imposes a fetal phenotype to intestinal stem cells.IκBα‐deficient mice are more resistant to intestinal damage. [ABSTRACT FROM AUTHOR]

Benefit from cytotoxic therapy in myeloma may be limited by the persistence of residual tumour cells within protective niches. We have previously shown that monocytes/macrophages acquire a proinflammatory transcriptional profile in the myeloma microenvironment. Here we report constitutive activation of MAP3K8 kinase-dependent pathways that regulate the magnitude and extent of inflammatory activity of monocytes/macrophages within myeloma niches. In myeloma tumour cells, MAP3K8 acts as mitogen-induced MAP3K in mitosis and is required for TNFα-mediated ERK activation. Pharmacological MAP3K8 inhibition results in dose-dependent, tumour cell-autonomous apoptosis despite contact with primary stroma. MAP3K8 blockade may disrupt crucial macrophage-tumour cell interactions within myeloma niches. [ABSTRACT FROM AUTHOR]

Summary: The dimeric transcription factor nuclear factor κB (NF-κB) functions broadly in coordinating cellular responses during inflammation and immune reactions, and its importance in the pathogenesis of cancer is increasingly recognized. Many of the signal transduction pathways that trigger activation of cytoplasmic NF-κB in response to a broad array of immune and inflammatory stimuli have been elaborated in great detail. NF-κB can also be activated by DNA damage, though relatively less is known about the signal transduction mechanisms that link DNA damage in the nucleus with activation of NF-κB in the cytoplasm. Here, we focus on the conserved signaling pathway that has emerged that promotes NF-κB activation following DNA damage. Post-translational modification of NF-κB essential modulator (NEMO) plays a central role in linking the cellular DNA damage response to NF-κB via the ataxia telangiectasia mutated (ATM) kinase. Accumulating evidence suggests that DNA damage-dependent NF-κB activation may play significant biological roles, particularly during lymphocyte differentiation and progression of human malignancies. [ABSTRACT FROM AUTHOR]

The transcription factor NF-κB has critical functions in biologic responses to genotoxic stimuli. Activation of NF-κB in response to DNA double strand break (DSB) inducers can be mediated by ATM (ataxia telangiectasia mutated)-dependent phosphorylation of NEMO (NF-κB essential modulator). Here, we show that the replication stress inducers hydroxyurea (HU) and aphidicolin also activate this ATM-dependent signalling pathway. We further show that ATR (ATM- and Rad3-related) interacts with NEMO but surprisingly does not cause NEMO phosphorylation. Consequently, ATR represses NF-κB activation induced by replication stress. Reduction or increase of ATR expression by RNA interference or overexpression increased or reduced ATM–NEMO association and NF-κB activation induced by HU. Apoptosis gene expression and chromatin immunoprecipitation analyses indicated that HU and the DSB inducer etoposide caused complex patterns of NF-κB-dependent pro- and antiapoptotic gene expression with the overall outcome for the former being pro-apoptotic, whereas the latter antiapoptotic. Thus, replication stress and DSB inducers activate NF-κB through a conserved pathway with opposite biologic outcomes, and ATR antagonizes ATM function at least in part by competing for NEMO association. [ABSTRACT FROM AUTHOR]

Small hepatocytes (SH), which are hepatic progenitor cells, were isolated from an adult rat liver. SH in a colony sometimes change their shape from small to large and from flat to rising/piled-up. The morphological changes of SH may be correlated with hepatic maturation. Cytochrome P450s (CYP) are drug-metabolizing enzymes and the expression is one of hepatic differentiated functions. However, it is well known that the re-expression and maintenance of CYP activity are very difficult in cultured hepatocytes. We investigated the expression of CYP and the enzymatic activities in long-term cultured SH.SH were isolated from adult rat livers and SH colonies were collected, replated on new dishes, and then cultured. CYP1A1/2, CYP2B1, CYP3A2, CYP4A1, and CYP2E1 were induced by the addition of 3-methylcholanthrene, phenobarbital, pregnenolone-16α-carbonitrile, clofibric acid, and ethanol, respectively. Immunocytochemistry, immunoblots, and enzyme activities were examined.SH could differentiate into mature hepatocytes by the addition of Matrigel and re-express constitutive CYPs. The expression of CYP1A1/2, CYP2B1, CYP3A2, and CYP4A1 dose-dependently increased and the amounts gradually increased with time in culture, especially in the cells treated with Matrigel. Activities of CYP1A, CYP2B, CYP3A and CYP2E in SH treated with Matrigel induced by each of the inducers were approximately 120-fold, 2.8-fold, 6.4-fold and 0.8-fold higher than in the control.The matured SH could re-express the constitutive CYP and recover inducibility, not only of protein expression but also of enzyme activities. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to investigate the actual condition of quick-acting insulin analog (Q) in Japanese children and adolescents with type 1 diabetes. Methods: Forty-seven physicians who managed 944 patients under 18 years of age with type 1 diabetes, were requested to complete questionnaires in May 2002 regarding the use of Q. Results: Q was administered to 417 out of 944 (44%) patients. The details of the daily insulin regimens were as follows: three doses of Q with basal insulin in 116 of 403 (29%), three doses of Q with more than twice the basal insulin in 69 of 403 (17%), and other modifications using either Q or regular insulin (R) depending on the patients’ lifestyles in 213 of 403 (53%). Q dose was equal to R after the change of insulin regimens in 232 of 290 (80%). After switching to Q from R, the basal insulin dosage increased in 113 of 341 (33%) and the number of basal insulin injections increased in 42 of 341 (12%). After the transfer to Q from R, glycemic control was judged to improve in 179 of 372 (48%), to have no significant change in 162 of 372 (44%), and to aggravate in 31 of 372 (8%). The majority of patients, (305/389; 78%), noted an improvement of quality of life (QOL) following the administration of Q. Conclusions: Q was considered to be useful in flexibility of daily insulin therapy and improvement of QOL in children and adolescents with type 1 diabetes. Insulin therapy for type 1 diabetes during childhood and adolescence should be tailored to meet individual needs. [ABSTRACT FROM AUTHOR]

Tropical pulmonary eosinophilia (TPE) is an occult manifestation of filariasis, brought about by helminth parasites Wuchereria bancrofti and Brugia malayi. Treatment of patients suffering from TPE involves the administration of diethyl carbamazine and Ivermectin. Although the drugs are able to block acute inflammation, they are not able to alleviate chronic basal inflammation. We have attempted to examine the disease by targeting two important components; namely filarial parasitic sheath proteins (FPP) induced apoptosis and pro-inflammatory cytokine response in human laryngeal carcinoma cells of epithelial origin (HEp-2) cells an epithelial cell line. Earlier studies by us have shown that FPP exposure induced apoptosis in these cells. In this study with hydrocortisone, calpain inhibitor (ALLN) and phorbol myristate acetate (PMA) treatments we demonstrate that apoptosis is inhibited as shown by [3H] thymidine incorporation studies, propidium iodide staining and Annexin V staining. Hydrocortisone at a dose, which inhibits cell death also down regulated, the expression of pro-inflammatory cytokines IL-6 and IL-8. These findings give us insights into the multifaceted approach one may adopt to target critical signalling molecules using appropriate inhibitors, which could eventually be used to reduce lung damage in TPE. [Copyright &y& Elsevier]

Tropical pulmonary eosinophilia is in part caused by the hyperimmune responsiveness of the lung tissue against the antigens of degenerating microfilariae. We have previously shown that the activation of the transcription factor NF-κB is essential for the synthesis and release of multiple pro-inflammatory cytokines in HEp-2 human airway epithelial cells following exposure to filarial parasitic sheath proteins (FPS). Neither the antigenic component nor the receptor involved in this activation is known. Herein we provide evidence that FPS activation of NF-κB can be augmented by the cell surface expression of CD14. CD14 expression, however, is not sufficient to transduce FPS signals for NF-κB activation, since its expression in different cell types does not always furnish the capacity to respond to FPS. We also show that NF-κB activation by FPS treatment can be distinguished from that induced by bacterial lipolysaccharide, an agent that can also activate NF-κB in a CD14-dependent fashion. These observations suggest that the capacity of certain lung epithelial cells to interact with microfilarial antigens, activate NF-κB in a CD14-dependent manner and produce pro-inflammatory cytokines may be a contributory factor to immune responses manifested by tropical pulmonary eosinophilia. [Copyright &y& Elsevier]

OBJECTIVEAlthough the polymorphisms of the cytotoxic T lymphocyte antigen 4 (CTLA4) gene have been shown to be associated with Type 1 diabetes in Caucasians, some conflicting results have been reported among subjects of different ethnic backgrounds. We examined a CTLA4 polymorphism and its relationship to human leucocyte antigen (HLA) genotypes and autoantibodies for glutamic acid decarboxylase 65 (GAD65) and IA-2 in Japanese children with Type 1 diabetes. SUBJECTS AND MEASUREMENTSThe study group consisted of 125 childhood-onset Japanese subjects (50 males, 75 females) with Type 1 diabetes. The CTLA4 A/G polymorphism at position 49 was analysed using a PCR-restriction fragment length polymorphism (PCR-RFLP) method. The HLA-DRB1 and DQB1 genotypes were defined by DNA analysis using PCR-sequence-specific oligonucleotide (PCR-SSO) probes. The GAD65 autoantibody (GAD65Ab) and IA-2 autoantibody (IA-2Ab) titres were measured using radioimmunoassay. RESULTSThe distribution of genotype frequencies differs between subjects with Type 1 diabetes (GG: 46%, AG: 50%, AA: 5%) and controls (GG: 39%, AG: 44%, AA: 17%) (P < 0·01). The frequency of the G allele is higher in the diabetes group than in the controls (P < 0·05). When the subjects were subdivided according to HLA genotype, the two major HLA high-risk groups, with DR9-DQ9 and DR4-DQ4, that are unique to Japanese populations showed no difference in their CTLA4 polymorphism frequencies. Although no association between the CTLA4 polymorphism and the prevalence of GAD65Ab was found, CTLA4 GG subjects that had been newly diagnosed (< 9 months) had significantly higher levels of autoantibodies than AG subjects (P < 0·01). The prevalence and titres of IA-2Ab were not associated with the CTLA4 polymorphism. CONCLUSIONSThe CTLA4 gene might confer a susceptibility to childhood-onset Type 1 diabetes in the Japanese population. The association between this CTLA4 polymorphism and the HLA genotype was similar for both... [ABSTRACT FROM AUTHOR]

R4727 --> Despite extensive clinical and basic science research, cardiovascular diseases continue to be the leading cause of death worldwide. In response to pathological insults, the heart attempts to adapt and normalize cardiac function by initiating a compensatory response that drives wound healing and remodeling of the myocardium. The immune system and its inflammatory mediators are currently recognized as active participants in cardiac disease progression and the development of heart failure. We have previously demonstrated that the cardiomyocyte is the initial site of proinflammatory gene transcription following transverse aortic constriction (TAC) and that this occurs through signal transduction by activated Ca2+/Calmodulin‐Dependent Kinase II (CaMKIIδ). Activation of cardiomyocyte CaMKIIδ transduces cardiac cellular stress signals into inflammatory gene expression via canonical NFκβ signaling and the NLRP3 inflammasome. The NLRP3 inflammasome is rapidly primed and activated in cardiomyocytes following TAC as indicated by caspase‐1 activation and generation of proinflammatory cytokines IL‐1β and IL‐18. Interleukin‐1β is regarded as a potent mediator of sterile inflammation often associated with neutrophilic infiltration, and its biological activity is tightly controlled by multiple levels of regulation including the requirement for proteolytic cleavage of the full‐length transcript to its biologically active form by active caspase‐1 recruited to the NLRP3 inflammasome complex. To investigate the role of the NLRP3 inflammasome in cardiomyocytes, we have generated mice with constitutive NLRP3 (designated as FCAS after the human mutation in familial cold autoinflammatory syndrome) expression in cardiomyocytes. This was achieved by administration of cardiomyocyte‐specific adeno‐virus associated virus serotype 9 (AAV9) expressing cre recombinase into mice floxed with the mutant FCAS gene. At the conclusion of 3 weeks after virus administration, a low dose of 2mg/kg lipopolysaccharide (LPS) was administered as a priming event for the transcription of inflammasome signaling components. At the conclusion of 6 hours after LPS injection, blood was collected for measurements of systemic inflammation, and whole hearts were collected for analysis NLRP3 priming (gene expression) and NLRP3 activation using qPCR and measuring caspase1 enzymatic activity. Inflammasome priming, as measured by an increase in Il‐18 and caspase‐1, were increased in FCAS LPS animals compared to wild type control LPS animals, although we did not observe differences in Il‐1β or NLRP3 gene expression. Whole ventricular tissue from these mice were probed for activated NLRP3 via the measurement of caspase‐1 enzymatic activity AAV9‐Cre administered mice with floxed FCAS gene increased NLRP3 inflammasome activation compared to virus injection into wild type mice, but there were no measured differences between FCAS LPS and wild type control LPS mice. Blood from FCAS LPS mice had significantly increased serum Il‐1β levels compared to control LPS mice suggesting that cardiomyocyte‐derived inflammasome products can contribute to appreciable levels of inflammation. [ABSTRACT FROM AUTHOR]

The development of feeder cables is being advanced for use in supplying power to propulsion coils to realize the Yamanashi experimental lines of a superconducting magnetic levitation railway (Maglev). A step voltage waveform is applied to the XLPE insulation of feeder cables by an inverter in which high frequencies are superimposed on the basic commercial frequency. The authors devised electrical testing equipment that can output such specific waveforms, and they investigated the effect of such waveforms on the insulation properties of XLPE cable, the breakdown characteristics of the model cables, and their long-term characteristics. As a result, it was learned that the insulation breakdown depends on the voltage waveform peak value and that the long-term characteristics are determined by the basic frequency. This knowledge will be useful for the insulation design of the feeder cable system of the Yamanashi experimental line. © 1999 Scripta Technica, Electr Eng Jpn, 129(2): 31–39, 1999 [ABSTRACT FROM AUTHOR]

Reports on two cases of insulin requiring diabetic patients accompanied by a hallucinatory-delusional state and diagnosed as having schizophrenia. Medical history of the patients; Results of the neurological examination conducted; Improvements observed on the patients after treatment.