Mosquito allergy and Epstein-Barr virus-associated T/natural killer-cell lymphoproliferative disease.
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Biomedical subjects
Publications and source records attributed to T Okamura.
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Cytokines and various cellular stresses are known to activate c-Jun N-terminal kinase-1 (JNK1), which is involved in physiological function. Here, we investigate the activation of JNK1 by oxidative stress in H9c2 cells derived from rat cardiomyocytes. H(2)O(2) (100 microM) significantly induces the tyrosine phosphorylation of JNK1 with a peak 25 min after the stimulation. The amount of JNK1 protein remains almost constant during stimulation. Immunocytochemical observation shows that JNK1 staining in the nucleus is enhanced after H(2)O(2) stimulation. To clarify the physiological role of JNK1 activation under these conditions, we transfected antisense JNK1 DNA into H9c2 cells. The antisense DNA (2 microM) inhibits JNK1 expression by 80% as compared with expression in the presence of the sense DNA, and significantly blocks H(2)O(2)-induced cell death. Consistent with the decrease in cell number, we detected condensation of the nuclei, a hallmark of apoptosis, 3 h after H(2)O(2) stimulation in the presence of the sense DNA for JNK1. The antisense DNA of JNK1 inhibits the condensation of nuclei by H(2)O(2). Under these conditions, the H(2)O(2)-induced phosphorylation of proteins with molecular masses of 55, 72, and 78 kDa is blocked by treatment with the antisense DNA for JNK1 as compared with the sense DNA for JNK1. These findings suggest that JNK1 induces apoptotic cell death in response to H(2)O(2), and that the cell death may be involved in the phosphorylations of 55, 72, and 78 kDa proteins induced by JNK1 activation.
BACKGROUND: During myocardial ischemia, massive norepinephrine (NE) is released from the cardiac sympathetic nerve terminals, reflecting the sympathetic nerve injury. A brief preceding ischemia can reduce infarct size; this is known as ischemic preconditioning (PC). The effect of PC on sympathetic nerves, however, including its underlying mechanisms in dog hearts, has remained unclear. Thus, this study was designed to elucidate whether the activation of ATP-sensitive potassium (K(ATP)) channels is involved in the mechanism of cardiac sympathetic nerve protection conferred by PC. METHODS AND RESULTS: Interstitial NE concentration was measured by the in situ cardiac microdialysis method in 45 anesthetized dogs. Five minutes of ischemia followed by 5 minutes of reperfusion was performed as PC. In the controls, the dialysate NE concentration (dNE) increased 15-fold after the 40-minute ischemia. PC decreased dNE at 40-minute ischemia by 59% (P<0.01), which was reversed by glibenclamide. A K(ATP) channel opener, nicorandil (25 microg. kg(-1). min(-1) IV), decreased dNE at 40 minutes of ischemia by 76% (P<0.01), which was also reversed by glibenclamide. During the PC procedure, no significant increase in dNE was detected, even with the uptake-1 inhibitor desipramine. CONCLUSIONS: Cardiac sympathetic nerve injury during myocardial ischemia was attenuated by PC via the activation of K(ATP) channels, but the trigger of the PC effect is unlikely to be NE release in dog hearts.
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Thirty patients with chronic active Epstein-Barr virus (CAEBV) infection were analyzed. The study group included 18 male and 12 female patients, ranging in age from 5 to 31 years with a mean age of 14.2 years. Not all patients had high titers of EBV-specific antibodies, but all patients had high viral loads in their peripheral blood (more than 10(2.5) copies/microg DNA). Fifty percent of the patients displayed chromosomal aberrations, and 79% had monoclonality of EBV. Patients were divided into 2 clinically distinct groups, based on whether the predominantly infected cells in their peripheral blood were T cells or natural killer (NK) cells. Over a 68-month period of observation, 10 patients died from hepatic failure, malignant lymphoma, or other causes. Patients with T-cell CAEBV had a shorter survival time than those with NK-cell type of disease.
The selectivity of 7-nitroindazole in inhibiting endothelial and neuronal nitric oxide synthases (eNOS and nNOS) was investigated by comparing its inhibitory action on relaxations mediated by nitric oxide (NO) in response to stimulation of perivascular nerves and in response to histamine in monkey cerebral artery strips. 7-Nitroindazole at 2 x 10(-5) M moderately attenuated the response to transmural electrical stimulation and to nicotine, but did to alter the endothelium-dependent relaxation in response to histamine in cimetidine-treated strips. Raising the concentration of 7-nitroindazole to 10(-4) M abolished the neurogenic response, partially inhibited the histamine-induced relaxation, but did not affect the response to NO. It is concluded that 7-nitroindazole is a relatively selective nNOS inhibitor; however, at high concentrations, it inhibits eNOS in monkey cerebral arteries.
A three-dimensional pharmacophore model of mesangial cell (MC) proliferation inhibitors was generated from a training set of 4-(diethoxyphosphoryl)methyl-N-(3-phenyl-[1,2,4]thiadiazol-5-yl)benzamide, 2, and its derivatives using the Catalyst/HIPHOP software program. On the basis of the in vitro MC proliferation inhibitory activity, a pharmacophore model was generated as seven features consisting of two hydrophobic regions, two hydrophobic aromatic regions, and three hydrogen bond acceptors. Using this model as a three-dimensional query to search the Maybridge database, structurally novel 41 compounds were identified. The evaluation of MC proliferation inhibitory activity using available samples from the 41 identified compounds exhibited over 50% inhibitory activity at the 100 nM range. Interestingly, the newly identified compounds by the 3D database searching method exhibited the reduced inhibition of normal proximal tubular epithelial cell proliferation compared to a training set of compounds.
Three five-component architectures, compounds 3, 4, and 5 were obtained by self-assembly of tripodal 1,3,5-tris(imidazol-1-ylmethyl )-2,4,6-trimethylbenzene (6) and 1,3,5-tris(benzimidazol-2-ylmethyl)benzene (7) ligands with silver(I) salts. The structures of these novel complexes have been determined by X-ray crystallography. The results of structural analysis indicate that these frameworks have same M3L2 components, but different structures. Compounds 3 and 4 are both M3L2 type cage-like complexes, while the 5 is an open trinuclear complex. The complex 3 is a cylindrical cage with simultaneous inclusion of a perchlorate anion inside of the cage as a guest molecule. Such guests can be exchanged for other anions through the open edge of the cage as evidenced by crystal structure of 4. The results demonstrate that the molecular M3L2 type cage can act as a host for anions and provide a nice example of supramolecular architectures with interesting properties and possible applications.
Canine cerebral arterial strips denuded of endothelium responded to nicotine and transmural electrical stimulation with relaxations, which were abolished by NG-nitro-L-arginine and methylene blue. Magnitudes of relaxation did not differ in the arteries contracted with prostaglandin F2alpha and sumatriptan, an effective therapeutic of migraine. Sumatriptan concentration-dependently contracted the arteries responding to 2 Hz stimulation with persistent relaxations, and the concentration of this 5-HT1B/1D/1F receptor agonist to overcome the relaxation averaged 1.06 x 10(-7) M. Acetylcholine inhibited the response to nerve stimulation due possibly to its action on prejunctional nitroxidergic nerves; the inhibition did not differ in the arteries contracted with prostaglandin F2alpha and K+. It appears that sumatriptan does not interfere with the release of nitric oxide from nerves but counteracts the neurogenic relaxation by functional antagonistic action on smooth muscle. Prejunctional inhibition by muscarinic receptor activation is unlikely associated with opening of neuronal K+ channels.
Sequencing studies of the protein S gene (PROS1) in a Japanese patient suffering from recurrent thrombosis revealed the following. The proband and his first daughter, but not the second daughter, were having the type I protein S (PS) deficiency due to a novel point mutation from A to G at the intronic acceptor splice site in intron 13 of the PROS1. In the affected daughter, exclusion of the aberrant allele was assessed by the BstX1 dimorphism of PROS1 at Pro626 (CCG/CCA). The reduced PS activities in the proband and his first daughter were apparently due to defective production of mRNA from the mutant allele.
To examine the relation of triglycerides with coronary heart disease among populations with low mean total cholesterol, the authors conducted a 15.5-year prospective study ending in 1997 of 11,068 Japanese aged 40-69 years (4,452 men and 6,616 women with mean total cholesterol = 4.73 mmol/liter and 5.03 mmol/liter, respectively), initially free of coronary heart disease or stroke. There were 236 coronary heart disease events comprising 133 myocardial infarctions, 68 angina pectoris events, and 44 sudden cardiac deaths. The coronary heart disease incidence was greater in a dose-response manner across increasing quartiles of nonfasting triglycerides for both sexes. The multivariate relative risk of coronary heart disease adjusting for coronary risk factors and time since last meal associated with a 1-mmol/liter increase in triglycerides was 1.29 (95% confidence interval (CI): 1.09, 1.53; p = 0.004) for men and 1.42 (95% CI: 1.15, 1.75; p = 0.001) for women. The trend was similar for myocardial infarction, angina pectoris, and sudden cardiac death. The relation of triglycerides with coronary heart disease was not influenced materially by total cholesterol levels or, in a subsample analysis (51% of total sample), by high density lipoprotein cholesterol levels. Nonfasting serum triglycerides predict the incidence of coronary heart disease among Japanese men and women who possess low mean values of total cholesterol. Further adjustment for high density lipoprotein cholesterol suggests an independent role of triglycerides on the coronary heart disease risk.
Aberrant hypermethylation of tumor suppressor genes plays an important role in the development of many tumors. Recently identified new DNA methyltransferase (DNMT) genes, DNMT3A and DNMT3B, code for de novo methyltransferases. To determine the roles of DNMT3A, DNMT3B, as well as DNMT1, in the development of leukemia, competitive polymerase chain reaction (PCR) assays were performed and the expression levels of DNMTs were measured in normal hematopoiesis, 33 cases of acute myelogenous leukemia (AML), and 17 cases of chronic myelogenous leukemia (CML). All genes were constitutively expressed, although at different levels, in T lymphocytes, monocytes, neutrophils, and normal bone marrow cells. Interestingly, DNMT3B was expressed at high levels in CD34(+) bone marrow cells but down-regulated in differentiated cells. In AML, 5.3-, 4.4-, and 11.7-fold mean increases were seen in the levels of DNMT1, 3A, and 3B, respectively, compared with the control bone marrow cells. Although CML cells in the chronic phase did not show significant changes, cells in the acute phase showed 3.2-, 4.5-, and 3.4-fold mean increases in the levels of DNMT1, 3A, and 3B, respectively. Using methylation-specific PCR, it was observed that the p15(INAK4B) gene, a cell cycle regulator, was methylated in 24 of 33 (72%) cases of AML. Furthermore, AML cells with methylated p15(INAK4B) tended to express higher levels of DNMT1 and 3B. In conclusion, DNMTs were substantially overexpressed in leukemia cells in a leukemia type- and stage-specific manner. Up-regulated DNMTs may contribute to the pathogenesis of leukemia by inducing aberrant regional hypermethylation. (Blood. 2001;97:1172-1179)
Macrothrombocytopenia with leukocyte inclusions is a rare autosomal dominant platelet disorder characterized by a triad of giant platelets, thrombocytopenia, and characteristic Döhle body-like leukocyte inclusions. A previous study mapped a locus for the disease on chromosome 22q12.3-q13.2 by genome-wide linkage analysis. In addition, the complete DNA sequence of human chromosome 22 allowed a positional candidate approach, and results here indicate that the gene encoding nonmuscle myosin heavy chain-A, NMMHC-A, is mutated in this disorder. Mutations were found in 6 of 7 Japanese families studied: 3 missense mutations, a nonsense mutation, and a one-base deletion resulting in a premature termination. Immunofluorescence studies revealed that NMMHC-A distribution in neutrophils appeared to mimic the inclusion bodies. These results provide evidence for the involvement of abnormal NMMHC-A in the formation of leukocyte inclusions and also in platelet morphogenesis.
The novel intramolecularly NH...O hydrogen-bonded Ca(II)-aryl sulfonate complex, [Ca2(SO3-2-t-BuCONHC6H4)2(H2O)4]n(2-t-BuCONHC6H4SO3)2n (1), sulfonate anion, (HNEt3)(SO3-2-t-BuCONHC6H4) (2a), (PPh4)(SO3-2-t-BuCONHC6H4) (2b), (n-Bu4N)(SO3-2-t-BuCONHC6H4) (2c), and sulfonic acid, 2-t-BuCONHC6H4SO3H (3), were synthesized. The structures of 1, 2a, and 2b depict the presence of the formation of NH...O hydrogen bonds between the amide NH and S-O oxygen for a series of compounds as determined by IR and 1H NMR analyses both in the solid state and in the solution state. Thus, the NH...O hydrogen bonds with neutral amide groups are available for investigation of the electronic state of the O- anion. The combined data from the IR and 1H NMR spectra indicate that the sulfonic acid, sulfonate anion, and Ca(II) complex have a substantially weak intramolecular NH...O hydrogen bond between the SO3 oxygen and amide NH. In the detailed comparison with the intense NH...O hydrogen bonds for the carboxylate, weak NH...O hydrogen bonds for sulfonate is due to the strong conjugation of the SO3- group with the lower nucleophilicity.
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OBJECTIVE: The effectiveness of positron emission tomography with (18)F-fluorodeoxyglucose (FDG-PET) for diagnosis of uterine sarcoma was evaluated in comparison to the effectiveness of magnetic resonance (MR) imaging and power Doppler imaging. METHOD: The cases of five Osaka City University Hospital patients diagnosed with uterine sarcoma based on histopathological examination, in whom FDG-PET, MR imaging, and power Doppler imaging studies had been performed preoperatively, were reviewed. A comparative study of the usefulness of these three imaging modalities for diagnosis of sarcoma was conducted. Tumors comprised three leiomyosarcomas, one endometrial stromal sarcoma, and one carcinosarcoma. RESULTS: FDG-PET examinations were 100% positive for the five sarcomas; MR imagings were 80% positive (four of five cases), and US was 40% positive (two of five cases). The mean standardized uptake value of the sarcomas was 4.5 +/- 1.3. CONCLUSION: The sarcoma lesions were clearly imaged by FDG-PET. FDG-PET may be a most useful diagnostic method for uterine sarcoma.
Airway inflammation leads to secretion of abnormal mucous glycoprotein and ciliary injury. To investigate the possible usefulness of carbocisteine against airway inflammation and events related to it, we conducted a study in SO2-exposed rats of the effects of carbocisteine and ambroxol, as an active control drug, on components of mucous glycoprotein (fucose, sialic acid and protein) in bronchoalveolar lavage fluid (BALF); on infiltration and activation of inflammatory cells in BALF; on tracheal and bronchial-ciliary lesions; and on cAMP levels in tracheal and alveolar tissues. Carbocisteine inhibited or improved all SO2-induced changes tested, and dosages of 125 and 250 mg/kg b.i.d. reduced fucose, sialic acid and protein contents, inflammatory cells (as markers of inflammation), free radicals, and elastase activity in BALF, and suppressed the development of ciliary lesions of the tracheal and bronchial mucosa, while ambroxol (10 mg/kg b.i.d.) showed no such effects. In addition, carbocisteine improved cAMP levels in the tracheal and alveolar tissues. These results indicate that carbocisteine is able to prevent the development of inflammation-related respiratory disease in this rat model, and that this remission of airway inflammation may be associated with carbocisteine-induced normalization of cAMP levels in tracheal and alveolar tissues as well as with its mucoregulant and anti-inflammatory effects. In conclusion, carbocisteine has a unique mucoregulant action and inhibits SO2-induced airway inflammation in a manner different from that of ambroxol.
We retrospectively analyzed 336 patients with primary chronic myelofibrosis from 203 medical institutes in Japan. Notwithstanding their heterogeneous treatments, the median survival in 298 patients that could be evaluated was 10.0 years. Average age at onset was 60.7 years. Men were affected 1.4 times more frequently than women. The factors associated with shorter survival included anemia, leukocytosis/leukocytopenia, thrombocytopenia, and increased blasts in the peripheral blood, and sex (male), age (>60), and the presence of symptoms. A new scoring system based on the peripheral blood findings (hemoglobin [Hb] level, platelet count, and rate of blast formation) at initial diagnosis clearly correlated with survival rate. Accordingly, patients could be categorized into 3 groups by severity grading. Through stepwise multivariate survival analysis, the significant prognostic factors were identified as the severity grading based on the new scoring system (P = .0002), age (P = .0024), sex (P = .0153), and Hb (P = .0198). Chromosomal abnormalities were found in 58 of 154 patients (38%), although these did not influence survival.