scispace - formally typeset
Search or ask a question

Showing papers by "Kumamoto University published in 1998"


Journal ArticleDOI

2,057 citations


Journal ArticleDOI
TL;DR: Pathological expansions of the polyalanine tract may cause mutated PABP2 oligomers to accumulate as filament inclusions in nuclei to cause autosomal recessive OPMD.
Abstract: Autosomal dominant oculopharyngeal muscular dystrophy (OPMD) is an adult-onset disease with a world-wide distribution. It usually presents in the sixth decade with progressive swallowing difficulties (dysphagia), eyelid drooping (ptosis) and proximal limb weakness. Unique nuclear filament inclusions in skeletal muscle fibres are its pathological hallmark. We isolated the poly(A) binding protein 2 gene (PABP2) from a 217-kb candidate interval on chromosome 14q11 (B.B. et al., manuscript submitted). A (GCG)6 repeat encoding a polyalanine tract located at the N terminus of the protein was expanded to (GCG)8-13 in the 144 OPMD families screened. More severe phenotypes were observed in compound heterozygotes for the (GCG)9 mutation and a (GCG)7 allele that is found in 2% of the population, whereas homozygosity for the (GCG)7 allele leads to autosomal recessive OPMD. Thus the (GCG)7 allele is an example of a polymorphism which can act either as a modifier of a dominant phenotype or as a recessive mutation. Pathological expansions of the polyalanine tract may cause mutated PABP2 oligomers to accumulate as filament inclusions in nuclei.

706 citations


Journal ArticleDOI
TL;DR: A missense variant, Glu298Asp, in exon 7 of the eNOS gene is identified and demonstrated that it is associated with both coronary spastic angina and myocardial infarction, which suggests thatIt is a genetic susceptibility factor for essential hypertension.
Abstract: Essential hypertension has a genetic basis. Accumulating evidence, including findings of elevation of arterial blood pressure in mice lacking the endothelial nitric oxide synthase (eNOS) gene, strongly suggests that alteration in NO metabolism is implicated in hypertension. There are, however, no reports indicating that polymorphism in the eNOS gene is associated with essential hypertension. We have identified a missense variant, Glu298Asp, in exon 7 of the eNOS gene and demonstrated that it is associated with both coronary spastic angina and myocardial infarction. To explore the genetic involvement of the eNOS gene in essential hypertension, we examined the possible association between essential hypertension and several polymorphisms including the Glu298Asp variant, variable number tandem repeats in intron 4 (eNOS4b/4a), and two polymorphisms in introns 18 and 23. We performed a large-scale study of genetic association using two independent populations from Kyoto (n=458; 240 normotensive versus 218 hypertensive subjects) and Kumamoto (n=421; 223 normotensive versus 187 hypertensive subjects), Japan. In both groups, a new coding variant, Glu298Asp, showed a strong association with essential hypertension (Kyoto: odds ratio, 2.3 [95% confidence interval, 1.4 to 3.9]; Kumamoto: odds ratio, 2.4 [95% confidence interval, 1.4 to 4.0]). The allele frequencies of 298Asp in hypertensive subjects were significantly higher than those in normotensive subjects in both groups (Kyoto: 0.103 versus 0.050, P<0.0017; Kumamoto: 0.120 versus 0.058, P<0.0013, respectively). No such disequilibrium between genotypes was significantly associated with any other polymorphisms we examined; the Glu298Asp variant was also not linked to any other polymorphisms. In conclusion, the Glu298Asp missense variant was significantly associated with essential hypertension, which suggests that it is a genetic susceptibility factor for essential hypertension.

528 citations


Journal ArticleDOI
TL;DR: The results of perfusion-sensitive MR imaging with gradient-echo echoplanar technique correlated with both histologic and angiographic vascularities.
Abstract: Our purpose was to evaluate the relationships between the ratio of maximum relative cerebral blood volume (rCBV) (rCBV ratio = rCBV[tumor]/rCBV[contralateral white matter]) and histologic and angiographic vascularities of gliomas using the gradient-echo echoplanar MR imaging technique. We also evaluated the usefulness of rCBV maps for grading gliomas.We examined 30 patients with histologically verified gliomas. Gliomas were classified as glioblastoma, anaplastic glioma with enhancement, anaplastic glioma without enhancement, and low-grade glioma. The maximum rCBV ratio of each glioma was compared with both histologic and angiographic vascularities, and the relationship between the maximum rCBV ratios and each type of glioma was established.The maximum rCBV ratios of the gliomas significantly correlated with both histologic and angiographic vascularities (p < .001). Mean values and SDs of maximum rCBV ratios of each type of tumor were 7.32+/-4.39 for glioblastomas, 5.84+/-1.82 for anaplastic gliomas with e...

448 citations


Journal ArticleDOI
TL;DR: The results suggest the “EPR effect” in solid tumor primarily arises from in the difference in clearance rate between the solid tumor and the normal tissues after initial penetration of the polymers into these tissues.
Abstract: The objective of this study was to investigate the molecular weight (MW) and time-dependence of the phenomenon termed "the enhanced permeability and retention" (EPR) effect in solid tumor, in particular to determine and define the early phase accumulation of macromolecules in tumor and normal tissues and the relationship between blood concentration and tissue clearance. As a model, radioiodinated N-(2-hydroxypropyl)methacrylamide (HPMA) copolymers of MW ranging from 4.5 K to 800 K were administered i.v. to mice bearing sarcoma 180 tumor. Within 10 min all HPMA copolymers accumulated effectively in the tumor regardless of MW (1.0-1.5% of injected dose per g of tumor). However, higher MW copolymers (> 50 K) showed significantly increased tumor accumulation after 6 h, while the lower MW copolymers (< 40 K) were cleared rapidly from tumor tissue due to rapid diffusion back into the bloodstream. Blood clearance was also MW-dependent; the lower MW copolymers displayed rapid clearance, with kidney radioactivity of the copolymers of MW < 20 K representing 24% of injected dose per g kidney at 1 min after i.v. administration. Within 10 min these copolymers passed through the kidney and were excreted in the urine. Higher MW copolymers consistently showed kidney levels of 3-5% dose per g kidney in the early phase with no time-dependent accumulation in kidney. There was also no progressive accumulation in muscle or liver, regardless of polymer MW. These results suggest the "EPR effect" in solid tumor primarily arises from in the difference in clearance rate between the solid tumor and the normal tissues after initial penetration of the polymers into these tissues.

444 citations


Journal Article
TL;DR: In this paper, the biological significance of free radical generation induced by viral and bacterial infections was discussed, where the level of xanthine oxidase (XO) at the infected sites was elevated to a great extent.
Abstract: In recent years, accumulated evidence indicates that free radical species and nitric oxide (NO) or its derivatives are the key denominators in carcinogenesis. Our present topics discussed in this article will focus on the biological significance of free radical generation induced by viral and bacterial infections. In influenza virus infection in mice, the level of xanthine oxidase (XO) at the infected sites was elevated to a great extent. The timing of paralleled induction of XO with that of inducible NO synthase (iNOS) indicates efficient simultaneous reaction: NO + O2*- --> ONOO- (peroxynitrite). Peroxynitrite formation was identified by immunostaining of nitrotyrosine at the local site of infected organs. Peroxynitrite exhibits unique chemical reactivities such as protein nitration, DNA-strand breakage, guanine nitration, etc., which may then bring about not only cytotoxic effect but also mutagenesis. Numbers of evidence in vitro and in vivo show that treatment with chemical carcinogens such as carbon tetrachloride and heterocyclic amines also generated superoxide. The chronic inflammatory reactions, e.g., zymosan- and silica-induced granuloma, revealed very similar free radical generation in vivo. In addition, most experimental solid tumors have elevated levels of iNOS in the tumor tissue, and NO thus generated facilitates vascular permeability, which accelerates nutritional supply to the tumor tissue and hence sustains the rapid tumor growth. These circumstantial evidences suggest that inflammatory responses induced by various pathogens would accelerate mutagenesis as well as tissue damage, whereas NO also sustains more effectively solid tumor growth when normal cells are transformed to tumor or carcinoma cells by the host-derived free radical species.

433 citations


Journal ArticleDOI
TL;DR: The missense Glu298Asp variant in the eNOS gene is found by the analysis of its entire 26 coding regions and is significantly associated with coronary spasm.
Abstract: Coronary spasm plays an important role in the pathogenesis of not only variant angina but also ischemic heart disease in general. However, the precise mechanism(s) by which coronary spasm occurs remains to be elucidated. Coronary spasm may arise from interactions between environmental and genetic factors. Endothelial-derived nitric oxide (NO) has been implicated in the control of vascular tone. We have recently shown that both basal and acetylcholine (ACh)-induced NO activities are impaired in the coronary arteries of patients with coronary spasm. The purpose of this study has been to elucidate the possible variants that occur in the coding region of the endothelial nitric oxide synthase (eNOS) gene and that may be associated with coronary spasm. After initial screening in the entire 26 coding regions of the eNOS gene, we found a missense Glu298Asp variant in exon 7 in patients with coronary spasm. We subsequently performed a larger scale study involving 113 patients with coronary spasm and 100 control subjects, who were all diagnosed by intracoronary injection of ACh. The analysis revealed a significant difference in the distribution of the variant between the coronary spasm group (21.2%) and control group (9.0%; P=0.014 for dominant effect). Thus, we have found the missense Glu298Asp variant in the eNOS gene by the analysis of its entire 26 coding regions. The variant is significantly associated with coronary spasm.

401 citations


Journal ArticleDOI
TL;DR: There was a significant association of the missense Glu298Asp variant of the eNOS gene with MI, which may be due to the impaired effects of NO on the cardiovascular system: dysregulation of vascular tone, platelet aggregation and leukocyte adhesion and smooth muscle cell proliferation, all of which promote coronary atherosclerosis and thrombosis.

355 citations


Journal ArticleDOI
01 Nov 1998-Immunity
TL;DR: In vitro study revealed that Adhesion of TIE2+ cells induced by Angiopoietin-1 enhanced the proliferation of hematopoietic progenitor cells and promoted the adhesion to fibronectin (FN) through integrins in Tie2-transfected cells and primary TIE1+ cells sorted from 9.5 d.p.c. P-Sp.

324 citations


Journal ArticleDOI
TL;DR: It is suggested that basigin is involved in intercellular recognition during implantation, and an important cell-surface molecule involved in early embryogenesis and reproduction.

287 citations


Journal ArticleDOI
TL;DR: In cultured hippocampal neurons, simulation of glutamate receptors can activate ERK signaling, for which elevation of intracellular Ca2+ is required and here, receptor-coupled tyrosine kinase activation has an association.
Abstract: Extracellular stimuli such as neurotransmitters, neurotrophins, and growth factors in the brain regulate critical cellular events, including synaptic transmission, neuronal plasticity, morphological differentiation and survival Although many such stimuli trigger Ser/Thr-kinase and tyrosine-kinase cascades, the extracellular signal-regulated kinases, ERK1 and ERK2, prototypic members of the mitogen-activated protein (MAP) kinase family, are most attractive candidates among protein kinases that mediate morphological differentiation and promote survival in neurons ERK1 and ERK2 are abundant in the central nervous system (CNS) and are activated during various physiological and pathological events such as brain ischemia and epilepsy In cultured hippocampal neurons, simulation of glutamate receptors can activate ERK signaling, for which elevation of intracellular Ca2+ is required In addition, brain-derived neurotrophic factor and growth factors also induce the ERK signaling and here, receptor-coupled tyrosine kinase activation has an association We describe herein intracellular cascades of ERK signaling through neurotransmitters and neurotrophic factors Putative functional implications of ERK and other MAP-kinase family members in the central nervous system are give attention

Journal ArticleDOI
TL;DR: Observations raise a possibility that other pharmacological agents that inhibit neutrophil activation used in conjunction with MPS or GM1 ganglioside may have a synergistic effect in the treatment of traumatic spinal cord injury in humans.

Journal ArticleDOI
02 Oct 1998-Cell
TL;DR: Results demonstrate that synaptic integration involving both GABA inhibition and NMDA receptor activation is essential for compound motor coordination and this integration can adapt after Golgi cell elimination so as not to evoke overexcitation by the reduction of NMDA receptors.

Journal Article
TL;DR: Results indicate that bradykinin, NO, and prostaglandins play an important role in enhanced vascular permeability in tumor tissue and sustain tumor growth, and more importantly, brady Kinin antagonists such as HOE 140 may be beneficial for the inhibition of tumor growth.
Abstract: The mechanism of the enhanced vascular permeability and retention (EPR) effect seen in solid tumors was investigated with sarcoma 180 (S-180) in mice by using the bradykinin receptor antagonist d-Arg-[Hyp3,Thi5,d-Tic7,Oic8]bradykinin] (HOE 140), the nitric oxide (NO) scavenger 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (PTIO), and the cyclooxygenase (prostaglandin synthase) inhibitor indomethacin. In the S-180 solid tumor model, administration of HOE 140 (0.65 or 1.3 µg/kg/8 h, s.c.), PTIO (167 mg/kg/2 h, four times/8 h, i.p.), or indomethacin (5 or 10 mg/kg/day, three times, i.p.) significantly suppressed the EPR effect in the tumor, and the combined administration of these agents achieved a stronger inhibition of the EPR effect than did each compound alone. Indomethacin (10 mg/kg/day, three times) plus PTIO (167 mg/kg/2 h, four times) given i.p. had the greatest inhibition (70%) on the EPR effect. When HOE 140 was administered s.c. at a dose of 13 µg/kg/12 h for 2 weeks after tumor inoculation, growth of the solid tumor was also suppressed by 32%, by tumor weight. In the ascitic form of S-180, i.p. administration of HOE 140 at 13 µg/kg/12 h initiated immediately after tumor inoculation significantly suppressed formation of S-180 tumor ascites; the life span of ascitic S-180 tumor-bearing mice was prolonged at the same dose of HOE 140. The expression of inducible NO synthase mRNA and of cyclooxygenase 2 mRNA in S-180 tumor tissue was highly elevated, as evidenced by Northern blotting and reverse transcription-PCR and by Southern blot analyses. These results indicate that bradykinin, NO, and prostaglandins play an important role in enhanced vascular permeability in tumor tissue and sustain tumor growth. More importantly, bradykinin antagonists such as HOE 140 may be beneficial for the inhibition of tumor growth.

Journal ArticleDOI
TL;DR: The origin, terminus and other DNA regions show three migration patterns during active partitioning of daughter chromosomes during the cell division cycle by FISH.
Abstract: We show the intracellular localization of the Escherichia coli replication origin (oriC) and chromosome terminus during the cell division cycle by FISH. In newborn cells, oriC is localized at the old-pole-proximal nucleoid border and the terminus at the new-pole-proximal nucleoid border. One copy of replicated oriC migrates rapidly to the opposite nucleoid border. These oriC copies are retained at both nucleoid borders, remaining at a constant distance from each cell pole. The terminus segment migrates from the nucleoid border to midcell and is retained there until the terminus is duplicated. The origin, terminus and other DNA regions show three migration patterns during active partitioning of daughter chromosomes.

Journal ArticleDOI
TL;DR: The aims of this study were to determine whether HPV DNA could readily be demonstrated in skin tumors, as well as in perilesional skin, of immunocompetent patients using two polymerase chain reaction primer sets, and the prevalence of infections in normal skin; andThe prevalence of HPV 38 or HPV 38 related viruses in melanoma.

Journal ArticleDOI
TL;DR: The results show that age, hemorrhagic diathesis, and initial leukocyte count are prognostic factors for APL treated with ATRA followed by intensive chemotherapy.
Abstract: PURPOSEWe conducted a multicenter study of differentiation therapy with all-trans retinoic acid (ATRA) followed by intensive chemotherapy in patients with newly diagnosed acute promyelocytic leukemia (APL) and analyzed the prognostic factors for predicting complete remission (CR), event-free survival (EFS), and disease-free survival (DFS).PATIENTS AND METHODSAll patients received ATRA until CR. If patients had an initial leukocyte count greater than 3.0 x 10(9)/L, they received daunorubicin (DNR) and behenoyl cytarabine (BHAC). During therapy, if patients showed blast and promyelocyte counts greater than 1.0 x 10(9)/L, they received additional DNR and BHAC. After achieving CR, patients received three courses of consolidation and six courses of maintenance/intensification chemotherapy.RESULTSOf 198 registered, 196 were assessable (age range, 15 to 86 years; median, 46) and 173 (88%) achieved CR. Multivariate analysis showed that no or minor purpura at diagnosis (P = .0046) and age less than 30 years (P = ....

Journal ArticleDOI
TL;DR: DnaK and DnaJ constitute the primary stress‐sensing and transducing system of the E. coli heat shock response, which detects protein misfolding with high sensitivity.
Abstract: The expression of heat shock genes in Escherichia coli is regulated by the antagonistic action of the transcriptional activator, the sigma32 subunit of RNA polymerase, and negative modulators. Modulators are the DnaK chaperone system, which inactivates and destabilizes sigma32, and the FtsH protease, which is largely responsible for sigma32 degradation. A yet unproven hypothesis is that the degree of sequestration of the modulators through binding to misfolded proteins determines the level of heat shock gene transcription. This hypothesis was tested by altering the modulator concentration in cells expressing dnaK, dnaJ and ftsH from IPTG and arabinose-controlled promoters. Small increases in levels of DnaK and the DnaJ co-chaperone (< 1.5-fold of wild type) resulted in decreased level and activity of sigma32 at intermediate temperature and faster shut-off of the heat shock response. Small decreases in their levels caused inverse effects and, furthermore, reduced the refolding efficiency of heat-denatured protein and growth at heat shock temperatures. Fewer than 1500 molecules of a substrate of the DnaK system, structurally unstable firefly luciferase, resulted in elevated levels of heat shock proteins and a prolonged shut-off phase of the heat shock response. In contrast, a decrease in FtsH levels increased the sigma32 levels, but the accumulated sigma32 was inactive, indicating that sequestration of FtsH alone cannot induce the heat shock response efficiently. DnaK and DnaJ thus constitute the primary stress-sensing and transducing system of the E. coli heat shock response, which detects protein misfolding with high sensitivity.

Journal ArticleDOI
TL;DR: Using immunofluorescence microscopy, it is found that SeqA protein, a regulator of replication initiation, is localized as discrete fluorescent foci in E. coli wild-type cells and MukB protein is required for correct localization of SequA complexes by an unknown mechanism.

Journal ArticleDOI
TL;DR: Remnant lipoprotein levels were independently associated with abnormal endothelium-dependent vasomotor function in large and resistance coronary arteries in humans, indicating that remnant lipoproteins may impair endothelial vasom motor function in human coronary arteries.
Abstract: Background—It remains undetermined whether triglyceride-rich lipoproteins are an independent risk factor for atherosclerosis. Methods and Results—The correlation of responses of coronary arterial d...

Journal ArticleDOI
TL;DR: During culturing of the yolk sac cells and hepatic hematopoietic cells on a monolayer of mouse stromal cell line, ST2, primitive or fetal macrophage colonies developed before the formation of monocyte colonies, suggesting the existence of a direct pathway of differentiation from primitive macrophages into fetal Macrophages during ontogeny.
Abstract: Primitive macrophages first develop in the murine and human yolk sac and then differentiate into fetal macrophages. Primitive or fetal macrophages enter the blood stream and migrate into the fetal liver. Fetal macrophages possess a high proliferative capacity and express antigens and peroxidase activity of resident macrophages with the progress of gestation; they become mature and then transform into Kupffer cells. In contrast, myelopoiesis and monocytopoiesis are not active in yolk sac hematopoiesis and in the early stages of hepatic hematopoiesis. Precursor cells of primitive or fetal macrophages exist and granulocyte/macrophage colony-forming cells develop in the yolk sac and in the early stages of fetal liver development, whereas macrophage colony-forming cells emerge and increase later in fetal liver development. In vitro, similar colonies were formed from each fetal hematopoietic cell in the presence of different macrophage growth factors. During culturing of the yolk sac cells and hepatic hematopoietic cells on a monolayer of mouse stromal cell line, ST2, primitive or fetal macrophage colonies developed before the formation of monocyte colonies, suggesting the existence of a direct pathway of differentiation from primitive macrophages into fetal macrophages during ontogeny. In severely monocytopenic mice induced by the administration of strontium-89, Kupffer cells have a proliferative capacity and are maintained by self-renewal. In macrophage colony-stimulating factor (M-CSF)-deficient (op/op) mice, the number of Kupffer cells is reduced, and they are characterized by immature morphology and a proliferative potential similar to that of primitive or fetal macrophages during ontogeny. Immediately after the administration of M-CSF to op/op mice, Kupffer cells start proliferating and become mature. This finding indicates that M-CSF plays an important role in the differentiation and proliferation of Kupffer cells. Microsc. Res. Tech. 39:350– 364, 1997. © 1997 Wiley-Liss, Inc.

Journal ArticleDOI
TL;DR: The additional accumulation of advanced glycation end products in soft, macular drusen and/or retinal pigment epithelial cells may play a role in the pathogenesis of CNVM formation in age-related macular degeneration.
Abstract: Objective To investigate the localization of Nϵ -(carboxymethyl)lysine (CML), a component and major immunologic epitope of advanced glycation end products, in aged eyes and choroidal neovascular membranes (CNVMs) surgically excised from eyes with age-related macular degeneration. Methods Immunohistochemistry for CML was performed using 8 snap-frozen, surgically excised CNVMs. Twelve eyes from patients aged 69 to 82 years and 2 donor eyes, 1 each from a 23-week-old fetus and 21-year-old patient, without age-related macular degeneration or diabetic retinopathy were also examined. To determine if retinal pigment epithelial cells in CNVMs accumulate advanced glycation end products, cytokeratin and CML were stained in paired serial sections. Results Soft, macular drusen and/or basal laminar and basal linear deposits were observed in 8 of 12 aged eyes. Each case showed CML accumulation, while overlying retinal pigment epithelial cells showed no accumulation in all 12 eyes. In CNVMs, however, retinal pigment epithelial cells showed CML accumulation in their cytoplasm. Conclusion The additional accumulation of advanced glycation end products in soft, macular drusen and/or retinal pigment epithelial cells may play a role in the pathogenesis of CNVM formation in age-related macular degeneration. Clinical Relevance Recently, advanced glycation end products have been found to play a role both in aging changes and neovascularization. Localization of advanced glycation end products in the above-mentioned tissue may lead to a better understanding of the pathogenesis of age-related macular degeneration.

Journal ArticleDOI
TL;DR: It is indicated that vitamin E treatment improved endothelium-dependent vasodilation and decreased plasma TBARS levels in patients with CSA, and increased oxidative stress may contribute to endothelial dysfunction and anginal attacks in patientswith CSA.

Journal ArticleDOI
TL;DR: The results suggest that Rho-kinase is essential not only for actomyosin regulation but also for segregation of glial filaments into daughter cells which in turn ensures correct cytokinetic processes.
Abstract: Rho-associated kinase (Rho-kinase), which is activated by the small GTPase Rho, regulates formation of stress fibers and focal adhesions, myosin fiber organization, and neurite retraction through the phosphorylation of cytoskeletal proteins, including myosin light chain, the ERM family proteins (ezrin, radixin, and moesin) and adducin. Rho-kinase was found to phosphorylate a type III intermediate filament (IF) protein, glial fibrillary acidic protein (GFAP), exclusively at the cleavage furrow during cytokinesis. In the present study, we examined the roles of Rho-kinase in cytokinesis, in particular organization of glial filaments during cytokinesis. Expression of the dominant-negative form of Rho-kinase inhibited the cytokinesis of Xenopus embryo and mammalian cells, the result being production of multinuclei. We then constructed a series of mutant GFAPs, where Rho-kinase phosphorylation sites were variously mutated, and expressed them in type III IF-negative cells. The mutations induced impaired segregation of glial filament (GFAP filament) into postmitotic daughter cells. As a result, an unusually long bridge-like cytoplasmic structure formed between the unseparated daughter cells. Alteration of other sites, including the cdc2 kinase phosphorylation site, led to no remarkable defect in glial filament separation. These results suggest that Rho-kinase is essential not only for actomyosin regulation but also for segregation of glial filaments into daughter cells which in turn ensures correct cytokinetic processes.

Journal ArticleDOI
12 Feb 1998-Nature
TL;DR: It is proposed that p85 acts as a signal transducer in the cellular response to oxidative stress, mediating cell death regulated by p53 and that its involvement in p53-mediated apoptosis is independent of PI(3)K.
Abstract: Reactive oxygen species have damaging effects on cellular components and so trigger defensive responses by the cell and even programmed cell death, although the mechanisms by which mammalian cells transmit signals in response to oxidative damage are unknown. We report here that the protein p85, a regulator of the signalling protein phosphatidyl-3-OH kinase (PI(3)K), participates in the cell death process that is induced in response to oxidative stress and that this role of p85 in apoptosis does not involve PI(3)K. We show that disruption of p85 by homologous recombination impairs the cellular apoptotic response to oxidative stress. Because the protein p53 is required for cell death induced by oxidative damage, we examined the relation between p85 and p53. Using a chimaeric p53 fusion protein with the oestrogen receptor (p53ER) to supply p53 (p53 is induced upon binding of p53ER to oestradiol) in a p53-deficient cell line, we found that p85 is upregulated by p53 and that its involvement in p53-mediated apoptosis is independent of PI(3)K. We propose that p85 acts as a signal transducer in the cellular response to oxidative stress, mediating cell death regulated by p53.

Journal ArticleDOI
TL;DR: In this paper, the Late Pleistocene-Holocene depositional sequence on the shelf in the East China Sea (ECS) is interpreted on the basis of the analyses of four sediment cores and high-resolution seismic reflection sub-bottom profiler records along a NE-SW across-shelf transect.

Journal ArticleDOI
TL;DR: Understanding the role of NO and oxygen radical generation in virus infections will provide insight into not only viral pathogenesis but also the host-pathogen interaction in microbial infections at a molecular level.
Abstract: The importance of free radical molecular species in the pathogenesis of various viral diseases has been increasingly recognized in recent years. Oxygen radicals such as superoxide (O2-) and hydroxyl radical (.OH) have been implicated as possible pathogenic molecules in viral disease pathogenesis. Much attention has been given to another simple inorganic radical [nitric oxide (NO)] in the host's defense mechanism and pathogenesis of virus infection. The NO synthesis pathway, in particular, the inducible isoform of NO synthase (iNOS), is expressed in different viral diseases via induction of proinflammatory cytokines such as interferon-gamma. iNOS produces an excessive amount of NO for a long time compared with other constitutive isoforms of NOS (i.e., neuronal NOS and endothelial NOS). Recent studies indicate that NO and O2- are produced in excess during the host's defense responses against various intruding microbes. Reactive nitrogen oxide species such as peroxynitrite (ONOO-) and NOx (NO2 and N2O3) are produced in biological systems through the reaction of NO with either O2- or O2. Among these reactive nitrogen species, ONOO- and its biological actions are of considerable interest in that ONOO- causes oxidation and nitration of amino acid residues of proteins and guanine of DNA, lipid peroxidation, and DNA cleavage. Because the ONOO- is formed via a diffusion-limited fast reaction of NO and O2-, it may be a dominant nitrogen oxide species during the host's defense reactions, when both NO and O2- are produced in excess. Thus, understanding the role of NO and oxygen radical generation in virus infections will provide insight into not only viral pathogenesis but also the host-pathogen interaction in microbial infections at a molecular level.

Journal ArticleDOI
TL;DR: In this article, a series of peridotite specimens were collected near one of the pseudotachylyte fault veins to investigate the mechanisms of shear localization, and microstructural analyses showed at least three deformation stages.

Journal ArticleDOI
TL;DR: Mutation analysis of 44 unrelated Puerto Rican and 24 unrelated non-Puerto Rican HPS patients is described and evidence that suggests locus heterogeneity for HPS is presented, including an apparent frameshift hot spot at codons 321-322.
Abstract: Hermansky-Pudlak syndrome (HPS) is a rare, autosomal recessive disorder in which oculocutaneous albinism, bleeding, and lysosomal ceroid storage result from defects of multiple cytoplasmic organelles-melanosomes, platelet-dense granules, and lysosomes. As reported elsewhere, we mapped the human HPS gene to chromosome segment 10q23, positionally cloned the gene, and identified three pathologic mutations of the gene, in patients from Puerto Rico, Japan, and Europe. Here, we describe mutation analysis of 44 unrelated Puerto Rican and 24 unrelated non-Puerto Rican HPS patients. A 16-bp frameshift duplication, the result of an apparent founder effect, is nearly ubiquitous among Puerto Rican patients. A frameshift at codon 322 may be the most frequent HPS mutation in Europeans. We also describe six novel HPS mutations: a 5' splice-junction mutation of IVS5, three frameshifts, a nonsense mutation, and a one-codon in-frame deletion. These mutations define an apparent frameshift hot spot at codons 321-322. Overall, however, we detected mutations in the HPS gene in only about half of non-Puerto Rican patients, and we present evidence that suggests locus heterogeneity for HPS.

Journal Article
TL;DR: The data indicate that MSR-A plays an essential role in the development of diet-induced atherosclerosis and it appears that other scavenger receptors, such as MARCO, CD36, and macrosialin/CD68, as well as uptake of VLDL are involved in foam cell formation during atherogenesis in MSr-A/LDLR double knockout mice.