Search PubMed⌕ Search

Biomedical subjects

M Ohno

Publications and source records attributed to M Ohno.

At least 91 records · Page 5Linked to original sources

Heme oxygenase-1 is upregulated in the kidney of angiotensin II-induced hypertensive rats : possible role in renoprotection.

In this study, we investigated the regulation and physiological role of heme oxygenase-1 (HO-1) in the kidney of rats with hypertension. Rats were continuously administered either angiotensin II (Ang II) or norepinephrine with an osmotic minipump for up to 7 days. Ang II infusion decreased the glomerular filtration rate (GFR) as determined through creatinine clearance (3.2+/-0.2 versus 1.2+/-0.2 mL/min with Ang II infusion, P<0.01) and increased proteinuria (9. 7+/-1.3 versus 28.1+/-7.2 mg/d with Ang II infusion, P<0.01). In contrast, norepinephrine did not alter these laboratory values. Ang II infusion significantly increased HO-1 expression in mRNA (442+/-98% of control at day 5, P<0.01) and protein levels (314+/-49% of control at day 5, P<0.01). Immunohistochemistry showed that in the kidney of normotensive rats, HO-1 was expressed mainly in the basal side in the renal tubules. After Ang II infusion, HO-1 staining was more extensively dispersed in the tubular epithelial cells. The intraperitoneal administration of zinc protoporphyrin, an HO inhibitor, to Ang II-infused rats further decreased GFR (0.8+/-0. 1 mL/min) and increased proteinuria (52.5+/-13.0 mg/d). In contrast, the administration of hemin, an HO inducer, ameliorated the Ang II-induced decrease in GFR (2.4+/-0.2 mL/min) and increase in proteinuria (9.3+/-4.5 mg/d). These data suggest that HO-1 upregulation in the kidney of Ang II-induced hypertensive rats may exert a renoprotective effect against Ang II-induced renal injury.

Angiotensin II↗

A case of progressive systemic sclerosis complicated by massive pleural effusion with elevated CA125.

A tumor marker, CA125, is known to increase in the serum or other body fluids in various malignancies such as ovarian cancer. Here we present a case of progressive systemic sclerosis (PSS) with massive pleural effusion, in which CA125 in the serum and pleural fluid were elevated. The serum level of CA125 decreased in accordance with the change of the pleural effusion. CA125 level may be an indicator for the activity of serositis in some cases with collagen vascular diseases.

CA-125 Antigen↗

[A case of gastric cancer with liver metastasis responding to low-dose CDDP/5-FU combination chemotherapy].

We reported a case of a 62-year-old female with gastric cancer accompanied by liver, Virchow and paraaortic lymph nodes, and bone metastasis (taken low-dose cisplatin (CDDP)/5-fluorouracil (5-FU) combination chemotherapy). CDDP (10 mg/body/day) was injected on 1-5 days i.v. and 5-FU (500 mg/body/day) was injected i.v. continuously on 1-7 days. This treatment cycle was repeated for 4 weeks. After 4 cycles, liver metastasis disappeared without severe side effects. Primary lesion and Virchow's lymph nodes metastasis were reduced. However, bone and paraaortic lymph node metastasis showed no response. It was considered that low-dose CDDP/5-FU combination chemotherapy was effective for liver and lymph nodes metastasis of gastric cancer in this case.

Adenocarcinoma↗

Slow N-acetyltransferase 2 genotype affects the incidence of isoniazid and rifampicin-induced hepatotoxicity.

SETTING: Japanese in-patients with pulmonary tuberculosis and normal liver function receiving treatment with isoniazid and rifampicin (INH + RMP). OBJECTIVE: To elucidate the relationship between N-acetyltransferase 2 (NAT2) genotype and the incidence of isoniazid + rifampicin-induced hepatotoxicity. DESIGN: Prospective study. After NAT2* genotyping, 77 patients were classified into three groups according to their NAT2* genotypes: rapid-type (a homozygote of NAT2*4), intermediate-type (a heterozygote of NAT2*4 and mutant alleles) and slow-type (a combination of mutant alleles). Their biochemical profiles of liver function test were investigated for 3 months to assess the development of serum aminotransferase elevation. RESULT: Of the 77 patients, 18.2% developed adverse hepatic reaction within the first month of INH + RMP treatment. A significant association was observed between hepatotoxicity and NAT2* genotype: compared with rapid-type, the relative risk was 4.0 (95% CI 1.94-6.06) for intermediate-type and 28.0 (95%CI 26.0-30.0) for slow-type. Especially in slow-type, the incidence of hepatotoxicity and serum aminotransferase elevation was significantly higher than in the other two types. CONCLUSION: Slow NAT2* genotype significantly affected the development of INH + RMP-induced hepatotoxicity. This suggests the possibility that NAT2* genotyping prior to medication may be useful in evaluating patients with high risk for INH + RMP-induced hepatotoxicity.

Adult↗

Coagulation and fibrinolysis factors in dialysis patients with and without ischemic heart disease.

Cardiovascular disease is the leading cause of death in patients with end-stage renal disease. In addition, abnormalities of coagulation and fibrinolysis have been reported in patients with uremia. However, whether these hemostatic abnormalities lead to cardiovascular disease in dialysis patients is currently unknown. Therefore, we investigated the association of hemostatic factors with ischemic heart disease (IHD) in patients on peritoneal dialysis and hemodialysis. The study patients comprised 30 continuous ambulatory peritoneal dialysis patients and 18 hemodialysis patients. Twenty healthy subjects served as controls. We evaluated each subject's hemostatic factors, including factor VII, factor XII, thrombin-antithrombin III complex (TAT), fibrinogen, plasmin-antiplasmin complex (PIC), plasminogen activator inhibitor (PAI-1), and D-dimer. In dialysis patients, IHD was diagnosed by documented myocardial infarction or positive result on coronary angiogram or by positive thallium myocardial scintigraphy. Factor VII, fibrinogen, PIC, and D-dimer levels were significantly higher in the two dialysis groups than in controls. All hemostatic variables were similar between the two dialysis groups. Subject age (p = 0.005), PIC (p = 0.005), and D-dimer level (p = 0.003) were significantly higher in patients with IHD than in patients without IHD in the dialysis groups. Multiple logistic regression analysis showed that only patient age and D-dimer levels were independent predictors of IHD. Adjusted odds ratio for IHD was 1.06 for each 10 ng/mL increase of D-dimer (p = 0.06). In CAPD patients, only D-dimer was independently associated with IHD (odds ratio: 1.06, p = 0.03). We conclude that multiple hemostatic abnormalities are present in dialysis patients and that elevated D-dimer levels are independently associated with prevalent IHD.

Antifibrinolytic Agents↗

[Two cases of acute lupus peritonitis].

We report two cases of systemic lupus erythematosus (SLE) diagnosed when acute peritonitis was appeared. Case 1 was a 20 year-old woman suffering from stomachache and right lower abdominal pain. Case 2 was a 40 year-old woman with diarrhea, epigastralgia, pollakisuria. In both cases, their peritoneal fluids were exudative with positive autoantibodies. After high dose steroid therapy, abdominal symptoms and ascites improved promptly. However, due to the complication of lupus nephritis, additional therapy was necessary. To characterize the feature of lupus peritonitis (LP), we examined the clinical and laboratory findings of LP from the literature. In patients with acute LP, abdominal pain, vomiting, diarrhea were significantly more common compared with chronic LP patients (P < 0.05), and fever, arthritis, central nervous system involvement and cystitis were more common. In patients with chronic LP, pleural effusion and pericardial effusion were more common compared with acute LP patients. Gastrointestinal manifestations such as abdominal pain, vomiting and diarrhea were more common in patients with acute LP compared with patients with chronic LP. Most patients with chronic LP were asymptomatic, ascites and serositis being the only clinical findings. The response to steroid therapy was better in acute LP.

Acute Disease↗

Increased leukotriene A(4) hydrolase expression in the heart of angiotensin II-induced hypertensive rat.

Leukotriene A(4) (LTA(4)) hydrolase is essential for the conversion of LTA(4) to LTB(4), an inflammatory lipid mediator. We investigated whether LTA(4) hydrolase was regulated in the heart by angiotensin II (ang II) infusion. Continuous ang II infusion via an osmotic minipump for up to 7 days upregulated mRNA and protein levels of LTA(4) hydrolase ( approximately 3.5-fold of control) in the heart in a pressor-dependent manner. Immunohistochemistry demonstrated intense LTA(4) hydrolase staining in the myofibroblast as well as migrated monocytes/macrophages. These data suggest that the cardiac LTA(4) hydrolase-LTB(4) system plays a positive role in the promotion of cardiac inflammation in hypertension.

Angiotensin II↗

Bradykinin-potentiating peptides and C-type natriuretic peptides from snake venom.

Cloning of cDNAs encoding bradykinin-potentiating peptides (BPPs)-C-type natriuretic peptide (CNP) precursor or its homologue was performed for cDNA libraries of Bothrops jararaca (South American snake), Trimeresurus flavoviridis, Trimeresurus gramineus and Agkistrodon halys blomhoffi (Asian snakes), all belonging to Crotalinae subfamily. Each cDNA library was constructed from the venom glands of a single snake to preclude ambiguity by intraspecies variation in venom components. Thirteen positive clones derived from B. jararaca were divided into two types depending on restriction sites. Differences in the nucleotide sequence arise at three locations and two of them accompanied amino acid conversions. Despite the differences, both types of cDNA clones encode the BPP-CNP precursor of 256 amino acid residues. Sequence analysis demonstrated that cDNA clones from three Asian snakes encode homologues of the BPP-CNP precursor from B. jararaca. In a precursor polypeptide, a signal sequence (approximately 25 aa) at the N-terminus is followed by sequences of BPP or the analogue (5-13 aa) with flanking spacer sequences (indefinite number of aa), an intervening linker sequence (approximately 144 aa) with unidentified function, and a CNP sequence (22 aa) with a preceding processing signal sequence (10 aa). cDNA clones from A. halys blomhoffi encode two distinct peptides in place of BPP, and T. flavoviridis and T. gramineus were shown to have considerably different sequences in the BPP domain from those known as BPP sequences. The present results provide evidence for a wide distribution of the orthologous gene expressing a series of bioactive peptides among Crotalinae subfamily.

3' Untranslated Regions↗

Balloon injury does not induce heme oxygenase-1 expression, but administration of hemin inhibits neointimal formation in balloon-injured rat carotid artery.

It has been shown that antioxidant agents act inhibitorily against neointimal formation after balloon injury, suggesting the role of oxidative stress as a promotor of intimal cell proliferation. Heme oxygenase-1 (HO-1) is an inducible form of heme catabolizing enzyme that is induced by and acts against oxidative tissue injury. In this set of experiments, we showed that HO-1 was present in newly formed neointima; however, arterial HO-1 expression did not increase in response to balloon injury in rat carotid artery. Intraperitoneal administration of hemin, a HO-1 inducer, for 5 consecutive days resulted in about a 4-fold increase of serum bilirubin concentration. In addition, hemin injection increased HO-1 protein expression in the carotid artery, the heart, the kidney, and the liver. In this condition, balloon injury-induced neointimal formation was markedly inhibited. Local application of tin protoporphyrin, a HO inhibitor, blocked this effect, suggesting that induced HO-1 in the carotid artery was responsible for the inhibition of neointimal formation after balloon injury. This study suggests that induction of the endogenous antioxidant gene can suppress neointimal formation after balloon injury.

Animals↗

Anti-Helicobacter pylori agents. 3. 2-[(Arylalkyl)guanidino]-4-furylthiazoles.

A series of 2-[(arylalkyl)guanidino]-4-[(5-acetamidomethyl)furan-2-yl]thiazole s and some 4-acetamidomethyl positional isomers were synthesized and evaluated for antimicrobial activity against Helicobacter pylori. Among the compounds that had potent antimicrobial activity (MIC < 0. 1 microgram/mL), compounds 31 and 36 additionally possessed H2 antagonist and gastric antisecretory activities. Though compound 51, an analogue incorporating a methyl group onto the furan nucleus of 36, and compound 54, a positional isomer of 51, also showed potent anti-H. pylori activity, the H2 antagonism profile was eliminated from these compounds. Thus, two types of potent anti-H. pylori agents could be derived from the same scaffold.

Animals↗

Heparin-binding epidermal growth factor-like growth factor mRNA expression in neonatal rat brain with hypoxic/ischemic injury.

The neuronal expression of mRNA of heparin-binding epidermal growth factor-like growth factor (HB-EGF) was investigated in immature rat brains. Two rat models were used in this study. One was a hypoxic/ischemic (HI) brain injury model, and the other was an N-methyl-d-aspartate (NMDA) intracerebral injection model. The former model was made by permanent ligation of the left carotid artery and subsequent exposure to 2 h of hypoxia. After the HI insult, the HB-EGF mRNA was assessed by a Northern blot analysis. The levels of transcripts for HB-EGF in the cerebral cortex and the hippocampus of the ligated side were significantly higher than those of non-treated rats from 3 to 24 h after the insult. The spatial distribution of the mRNA of HB-EGF was also studied using in situ hybridization. Three to 24 h after the hypoxia, hybridization signals were intense in neuronal cytoplasm on the ligated side, but a focally decreased signal was seen in infarcted areas. Strongly increased mRNA expression was observed in the neurons surrounding the infarct. These results indicate that a neonatal HI insult induces a neuronal upregulation of HB-EGF immediately after hypoxia. In the latter model, the intracerebral NMDA injection also induced an immediate, strong upregulation of HB-EGF transcripts. Our results indicate that HB-EGF may act as a neuroprotective factor in the immature brain with HI injury by modulating the neurotoxic process which is mediated by overactivation of the NMDA receptor.

Animals↗

The nuclear cap-binding complex is a novel target of growth factor receptor-coupled signal transduction.

In an attempt to further understand how nuclear events (such as gene expression, nuclear import/export, and cell cycle checkpoint control) might be subject to regulation by extracellular stimuli, we sought to identify nuclear activities under growth factor control. Using a sensitive photoaffinity labeling assay that measured [alpha-32P]GTP incorporation into nuclear proteins, we identified the 20-kDa subunit of the nuclear cap-binding complex (CBC) as a protein whose binding activity is greatly enhanced by the extracellular stimulation of serum-arrested cells. The CBC represents a 20- and 80-kDa heterodimer (the subunits independently referred to as CBP20 and CBP80, respectively) that binds the 7-methylguanosine cap on RNAs transcribed by RNA polymerase II. This binding facilitates precursor messenger RNA splicing and export. We have demonstrated that the [alpha-32P]GTP incorporation into CBP20 was correlated with an increased ability of the CBC to bind capped RNA and have used the [alpha-32P]GTP photoaffinity assay to characterize the activation of the CBC in response to growth factors. We show that the CBC is activated by heregulin in HeLa cells and by nerve growth factor in PC12 cells as well as during the G1/S phase of the cell cycle and when cells are stressed with UV irradiation. Additionally, we show that cap-dependent splicing of precursor mRNA, a functional outcome of CBC activation, can be catalyzed by growth factor addition to serum-arrested cells. Taken together, these data identify the CBC as a nuclear target for growth factor-coupled signal transduction and suggest novel mechanisms by which growth factors can influence gene expression and cell growth.

Animals↗

Meiosis: MeiRNA hits the spot.

The protein Mei2 performs at least two functions required in fission yeast for the switch from mitotic to meiotic cell cycles. One of these functions also requires meiRNA. It appears that meiRNA targets Mei2 to the nucleus, where it can promote the first meiotic division.

Biological Transport↗

Increased interleukin-4 production by NK T cells in systemic lupus erythematosus.

It has been reported that production of interleukin (IL)-4, a T helper (Th)-2-type cytokine, might play an important role in the pathogenesis of systemic lupus erythematosus (SLE). On the other hand, it is known that NK1.1(+) cells which belong to CD4, CD8 double-negative, or CD4(+) cells are associated with initial IL-4 production and Th2 differentiation in mice although human equivalent cells are unknown. In order to study the profile of IL-4-producing cells in SLE, cytoplasmic IL-4 and various surface antigens on peripheral mononuclear cells were analyzed. Peripheral mononuclear cells were stimulated for 5 h by phorbol ester and ionomycin in the presence of monensin, fixed, and permeabilized with paraformaldehyde and saponin solution. Then cytoplasmic IL-4 and various surface antigens were analyzed by flow cytometry. IL-4-producing cells in SLE were phenotypically the same as those which produce IL-4 normally and frequently bore activated T-cell (CD7, CD25, CD28, CD29) and NK-cell markers (CD56, CD57). Double-negative T cells and CD57(+) T cells were increased in number and were more frequently positive for cytoplasmic IL-4 in SLE compared with normal controls and various infectious diseases. It was suggested that T cells with NK cell markers, CD57(+) T cells, which are known to extrathymically differentiate, might be involved in the pathogenesis of SLE as a counterpart of mouse NK1.1(+) cells.

Adult↗

The concurrent expression of p27(kip1) and cyclin D1 in epithelial ovarian tumors.

Mammalian cell-cycle progression is regulated by the combined action of cyclins/cyclin-dependent kinases (cdks) and cdk inhibitors. Abnormal expression as well as interaction of these proteins may result in malignant transformation of cells. To further address alterations and roles of these cell-cycle proteins in the development of epithelial ovarian carcinomas, we analyzed the expression of the p27(kip1), cyclin D1, cyclin E, and cdk2. A panel of 79 epithelial ovarian tumors was selected. Immunohistochemical staining of serial paraffin sections was performed using antibodies to p27(kip1), cyclin D1, cyclin E, and cdk2. The results showed that p27(kip1) and cyclin D1 were concurrently expressed in epithelial ovarian tumors, and the expression was down-regulated in ovarian carcinomas. There was an inverse relationship between the expression level of p27(kip1) and cyclin D1 and the histological tumor grades. On the other hand, the expression of cyclin E and cdk2 was enhanced in ovarian carcinomas. The results suggest that low expression of p27(kip1) and cyclin D1 as well as high expression of cyclin E and cdk2 promotes the development of ovarian tumors. p27(kip1) and cyclin D1 expression are negatively correlated with the malignant degree of epithelial ovarian tumors. Thus, the ovarian tumors with high p27(kip1) and cyclin D1 expression may generally have a somewhat better prognosis, while those with low p27(kip1) and cyclin D1 expression may have a worse prognosis.

CDC2-CDC28 Kinases↗

Expression of nm23-H1 in colorectal cancer: no association with metastases, histological stage, or survival.

The correlations of nm23-H1 expression in primary cancer lesions with the already confirmed 14 prognostic variables and survival were examined in 52 advanced colorectal cancer patients, because the clinical roles of nm23-H1 expression in the cancer lesions remain controversial. An immunohistochemical expression of nm23-H1 was found in 23 lesions (positive group) but not found in 29 lesions (negative group). No significant difference between the positive and negative groups was found according to 12 clinicopathological variables including vascular invasion, lymph node and liver metastases, and histological stage. The carcinoembryonic antigen levels (21.5+/-33.4 ng/ml) of the draining venous blood and argyrophilic nucleolar organizer regions score (3.35+/-1.36 per nucleus) of the cancer cells in the positive group were not significantly diffeent from those (34.1+/-102.9 ng/ml and 3.32+/-1.00 per nucleus, respectively) in the negative group. In addition, no significant difference was found in the survival curves or the 5-year survival rates of the positive and negative groups. From these results, it may be concluded that the nm23-H1 expression was not associated with the aforementioned prognostic variables and the prognosis of advanced colorectal cancer patients.

Aged↗

Clinicopathologic variables affecting survival of distal colorectal cancer patients with macroscopic invasion into the adjacent organs.

A total of 506 distal colorectal cancer patients were classified into two groups, to clarify the variables affecting survival of the patients with macroscopic invasion into the adjacent organs: 47 cases showed invasion (invasive group) while the other did not show invasion (noninvasive group). Differences between the invasive and noninvasive groups were found in eight variables; female, large tumor size, gross types 3 and 4, moderately or poorly differentiated adenocarcinomas and signet-ring cell or mucinous carcinomas, deep cancer invasion, lymphatic invasion, peritoneal and liver metastases, and curability B-C were found significantly more frequently in the invasive group. The survival curve of the former was significantly (P < 0.05) lower than that of the latter. However, no significant difference was found between the survival curves of the patients with curability A (no residual tumors) in both groups. A multivariate analysis in the invasive groups revealed six variables to be significantly related to a good prognosis including a young age, females, a location above the peritoneal reflection, well differentiated adenocarcinoma, negative lymphatic invasion, and curability A. Surgery with curability A should be performed to improve the survival in distal colorectal cancer patients with macroscopic invasion into the adjacent organs.

Adenocarcinoma↗