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Biomedical subjects

M Hara

Publications and source records attributed to M Hara.

At least 55 records · Page 3Linked to original sources
PubMed2003

Serum nitric oxide (NO) levels in systemic sclerosis patients: correlation between NO levels and clinical features.

Vascular damage in systemic sclerosis (SSc) may be a factor in the abnormal regulation of several vasoactive agents. It has been well confirmed that plasma endothelin-1, as a vasoconstrictive factor, is elevated in patients with SSc. However, it is still controversial whether the levels of serum nitric oxide (NO), a strong vasodilator, are increased or decreased in SSc patients compared to healthy donors. In this study, we measured the levels of serum NO metabolites in SSc patients and determined the contribution of the excessive production of NO synthase (NOS)-2 by skin fibroblasts to NO synthesis. Serum NO levels of 45 patients with SSc were significantly higher than those of 20 healthy volunteers. In addition, some clinical features of SSc (the extent of skin fibrosis, short disease duration, and the complication of active fibrosing alveolitis) were all correlated positively with the levels of NO metabolites in SSc patients. To evaluate the levels of NOS-2 produced by skin fibroblasts, skin fibroblast cultures were established from SSc patients and healthy volunteers. Reverse transcription-polymerase chain reaction indicated that NOS-2 mRNA was spontaneously expressed in cultured fibroblasts derived from SSc patients, but not in those derived from healthy normal controls. Immunohistochemical staining also showed that NOS-2 proteins were detected in SSc fibroblasts but not in normal fibroblasts. The production of NO by cultured fibroblasts was visualized directly by a reagent (DAF-2 DA) used for the fluorescent detection of NO. Cultured SSc fibroblasts were capable of NO synthesis in culture media containing L-arginine, whereas normal fibroblasts (with no expression of NOS-2) did not synthesize detectable NO. These observations indicate that NO production is increased markedly in early-stage diffuse cutaneous SSc patients with active fibrosing alveolitis, and that constitutive NOS-2 expression in SSc fibroblasts may contribute to increased NO production.

Adolescent↗
PubMed2002

Phylogenetic analysis of field isolates of feline calcivirus (FCV) in Japan by sequencing part of its capsid gene.

The molecular epidemiology of the infectious disease caused by feline calcivirus (FCV) in Japan was investigated by analysing the phylogenetic relationship among 21 Japanese field isolates, including the F4 strain, and 30 global isolates. Parts of the capsid gene (B-F) of the isolates were amplified by RT-PCR, and the amino acid sequences were compared with those from the global isolates. Thirty-seven and 14 out of a total of 51 isolates were clustered into two distinct genogroups, I and II respectively, by UPGMA and NJ analysis. Seven of the 21 Japanese isolates (33%) fell into group I together with 30 global isolates, while the other 14 Japanese isolates (67%) belonged to group II. The bootstrap repetition analysis of groups I and II formed by the NJ method gave a value of 99.00%. The 14 latter Japanese isolates were clearly separated from the isolates in group I, and they were different from any previously known FCV, forming a new genogroup, which implies that this lineage has been confined to Japan. Comparing the amino acid sequences shared by groups I and II, the amino acid at position 377 in B region was asparagine (Asn or Asp (NH2)) in group I, while it was lysine (Lys) in all the strains in group II. Similarly, the amino acid at position 539 in the F region was alanine (Ala) or proline (Pro) in group I, while it was valine (Val) in group II; glycine (Gly) at position 557 in group I was serine (Ser) in Group II; and phenylalanine (Phe) or leucine (Leu) at position 566 in genogroup I was tyrosine (Tyr) in group II.

Amino Acid Sequence↗
PubMed2002

Clonal expansion of limited T cell clonotypes in affected muscle from a patient with post-transplant polymyositis.

Critical roles of T cells in idiopathic polymyositis have been suggested, but, those in polymyositis occurring as GVHD after BMT are poorly understood. We thus investigated T cell clonality in a patient with post- transplant polymyositis. As a result, T cell receptor beta chains used various BV families in peripheral blood, but only one BV family (BV7) in affected muscle. Importantly, T cells proliferated oligoclonally both in the peripheral blood and the muscle, however, the expanded clonotypes were completely different. Taken together, T cells expanded in the muscle, possibly stimulated by limited kinds of antigens, may drive myositis.

Adult↗
PubMed2002

Association between adult-onset Still's disease and interleukin-18 gene polymorphisms.

Recently, we reported that serum concentration of IL-18 is strikingly high in patients with adult-onset Still's disease (AOSD). The aim of the present study was to screen for genetic polymorphisms in the human IL-18 (hIL-18) gene and to determine the association of polymorphisms with susceptibility to AOSD. We investigated the 6.7 kb region upstream of exon 2 of hIL-18 gene, in which a promoter activity had been reported. Sixteen AOSD patients, 144 rheumatoid arthritis (RA) patients and 92 healthy control individuals were studied. We found seven single nucleotide polymorphisms and a single 9 bp insertion which were frequently present in the AOSD patients. Three haplotypes including a unique combination of these polymorphisms were also determined. Of them, haplotype S01 contained all eight of these polymorphisms. The frequency of individuals carrying a diplotype configuration, ie a combination of two haplotypes, of S01/S01 was significantly higher in the AOSD patients than in the healthy controls (P=0.00059, Fischer's exact probability test, odds ratio [OR]=7.81, 95% confidence interval [95% CI]=2.48-24.65) and the RA patients (P=0.015, Fischer's exact probability test, OR=4.0, 95% CI=1.39-11.54). We therefore conclude that possession of the diplotype configuration of S01/S01 is a major genetic risk factor for susceptibility to AOSD.

Female↗
PubMed2002

Evaluation of gastric emptying measured with the 13C-octanoic acid breath test in patients with functional dyspepsia: comparison with ultrasonography.

BACKGROUND: As a non-invasive modality by which to evaluate the gastric emptying of a solid meal, the 13C-octanoic acid breath test has recently become more widely used. Previously, we reported that ultrasonography was another non-invasive and reliable method for assessing gastric motility. The aim of this study was to compare the reliability of these two methods. METHODS: Seventeen patients with functional dyspepsia and 10 healthy volunteers were studied. The solid test meal consisted of a scrambled egg labeled with 13C-octanoic acid (100 mg) and served with a bowl of rice and boiled chicken (total 424 kcal). After ingestion of the test meal, all subjects were examined in the sitting position. Ultrasonography images were obtained every 15 min for 3 h. Breath sampling followed the same time schedule as for the ultrasonography, with an additional 3 h of sampling at 30-min intervals. We investigated the half emptying time (T1/2) and the lag phase with both methods. RESULTS: The T1/2 by the ultrasonography method and the breath test were positively correlated (r2 = 0.638); however, there was no significant agreement between the study groups. Both the T1/2 and the lag phase were prolonged in the functional dyspepsia patients compared with the healthy volunteers, regardless of the method of measurement. The lag phase was significantly correlated (r2=0.864) with the T1/2 by the breath test. CONCLUSIONS: Although the 13C-octanoic acid breath test cannot assess the gastric emptying of solids as reliably as ultrasonography, both tests are useful for evaluating functional dyspepsia patients with delayed gastric emptying.

Adolescent↗
PubMed2002

Biopsy pathology predicts patients with ulcerative colitis subsequently requiring surgery.

BACKGROUND: The clinical course of patients with ulcerative colitis (UC) is unpredictable, and 17%-38% ultimately require surgery. We hypothesized that mucosal histology may differ between patients requiring surgery and those receiving medication alone. The aim of this study was to elucidate comprehensive criteria consisting of specific histologic features enabling the prediction of failure to medical treatment. METHODS: We studied colorectal biopsy specimens from 67 patients ultimately requiring surgery (UC-S) and 90 receiving medication alone for more than 3 years (UC-M), and conducted multiple logistic regression analysis on 70 histologic features together with endoscopic disease extent and patient age. The analysis constructed an equation finding probability of UC-S (P(UC-S)). Based on a receiver-operating characteristic curve, we selected four cut-off values of P(UC-S), and determined criteria of five categories: highest-risk, higher-risk, unpredictable, lower-risk and lowest-risk of surgery. Sensitivity and specificity of criteria were evaluated in a 2 x 5 table. RESULTS: Statistically significant features predicting UC-S were deep ulceration (X1), frequent crypt abscesses (X2), focal and segmental mononuclear cell infiltration (X3 and X4), paucity of eosinophils (X5: eosinophil infiltration) and wide extent of the disease (X6). The regression equation was as follows: logitP(UC-S) = -16.26 + 3.20X1 + 4.83X2 + 11.65X3 + 5. 10X4 - 5.59X5 + 5.53X6. Higher-risk and lower-risk showed sensitivity exceeding 91.0% and specificity exceeding 98.5% in predicting the outcome. CONCLUSIONS: Our criteria incorporating specific histologic features and endoscopic disease extent reliably predict eventual clinical outcome, and are expected to prove useful in determining the necessity of surgery.

Adult↗
PubMed2002

Comparative effects of plasmapheresis and intravenous cyclophosphamide on urinary podocyte excretion in patients with proliferative Lupus nephritis.

Intravenous cyclophosphamide (IVC) in combination with steroids is standard therapy for Lupus nephritis. Reduction of autoantibodies and circulating immune complexes can be used in the treatment of autoimmune diseases. The aim of the present study was to compare the effects of IVC pulse therapy and double-filtration plasmapheresis (DFPP) on proteinuria and urinary excretion of podocytes in adult patients with diffuse proliferative Lupus nephritis (DPLN). Twenty patients were randomly assigned to two groups. Group A (n = 10) was treated with IVC (0.75 - 1.0 g/m2 body surface area) pulse therapy, given as boluses once a month for 6 consecutive months, combined with oral corticosteroid (up to 1 mg/kg/day) administration. Group B (n = 10) was treated with a combination of DFPP (performed 1-2 times weekly) and corticosteroid (up to I mg/kg/ day). The total average number of treatments was 8.4 and the therapeutic efficacies were evaluated after 6 months. Twenty healthy individuals participated as a control group. Urinary podocytes were examined by immunofluorescence with monoclonal antibodies against podocalyxin. Both Group A and Group B reduced proteinuria (p < 0.001) as well as the number of urinary podocytes (p < 0.001). Differences between the 2 treatment outcomes were not statistically significant. Cyclophosphamide pulse therapy and DFPP may be similarly effective in the treatment of podocyte injury in patients with DPLN.

Adult↗
PubMed2001

Osmotic stress up-regulates aquaporin-3 gene expression in cultured human keratinocytes.

Of ten members of the aquaporin family (AQP), the mRNA expression and regulation of AQP1, AQP3, AQP4 and AQP9 in cultured human keratinocytes were examined by an RNase protection assay. AQP3 mRNA was expressed in growing and differentiating cells, while AQP9 mRNA was only detected in differentiating cells. The epidermis in skin-equivalent cultures expressed both AQP3 and AQP9 mRNA. However, neither AQP1 nor AQP4 mRNA was detectable in either monolayer or skin-equivalent cultures. Incubation of keratinocytes in sorbitol-added hypertonic medium increased AQP3 mRNA expression. This was confirmed using other solutes such as NaCl, mannitol, glucose and sucrose. The effect of sorbitol was reversible, dose-dependent and maximal at 24 h after addition. However, AQP1, AQP4 and AQP9 mRNA expression were unchanged under any of the hypertonic conditions examined. These findings indicated that osmotic stress up-regulates AQP3 gene expression in cultured keratinocytes.

Aquaporin 1↗
PubMed2001

Exclusive association of paraoxonase 1 with high-density lipoprotein particles in apolipoprotein A-I deficiency.

Paraoxonase1 (PON1) is a high-density lipoprotein (HDL)-associated protein which removes peroxidized lipids from lipoproteins. It has been proposed that apolipoprotein A-I (apoA-I) is an important determinant for its stabilization on HDL. However, little is known about its existence and activity in an apoA-I-deficient state in humans. To characterize the nature of PON1 in apoA-I deficiency, we investigated PON1 in an apoA-I-deficient patient. When serum was analyzed on fast protein liquid chromatography, PON1 protein was distributed almost exclusively on HDL despite the absence of apoA-I; on the other hand, 38.5% of PON1 protein was found in the lipoprotein-free fraction when the lipoproteins were fractionated through ultracentrifugation. The stability of PON1 activity in the patient serum was almost the same as in the normal control sera throughout incubation at 14 degrees C for 7 days. However, when the sera were incubated at 37 degrees C for 24 h, its activity declined more than those in the normal controls (19% versus 4% reduction of the initial values). Our results demonstrated that PON1 protein possesses a preferential association with HDL even in the absence of apoA-I, although apoA-I is a crucial factor for the maximal activity and stabilization of PON1.

Aged↗
PubMed2001

Neutralization of interleukin-1beta in the acute phase of myocardial infarction promotes the progression of left ventricular remodeling.

OBJECTIVES: We sought to examine the role of the pro-inflammatory cytokine, interleukin-1-beta (IL-1beta), in the process of left ventricular (LV) remodeling in the early phase after myocardial infarction (MI). BACKGROUND: Studies have shown that pro-inflammatory cytokines are closely related to the progression of LV remodeling after MI. METHODS: Mice underwent coronary artery ligation, and the time course of LV remodeling was followed up to 20 weeks. The gene expression level of IL-1beta was examined. In a second set of experiments, the mice underwent coronary artery ligation followed by treatment with anti-IL-1beta antibody (100 microg, intravenously), versus control immunoglobulin G (100 microg, intravenously) immediately after the operation. RESULTS: Rapid hypertrophy of noninfarcted myocardium was observed by four weeks, and interstitial fibrosis progressed steadily up to 20 weeks. Anti-IL-1beta treatment increased the occurrence of ventricular rupture and suppressed collagen accumulation in the infarct-related area. At four and eight weeks after the operation, total heart weight and LV end-diastolic dimension were significantly greater in the anti-IL-1beta-treated mice than in the other groups. In the infarct-related area, collagen accumulation was suppressed, whereas in the noninfarcted area, pro-collagen gene expression levels, particularly type III, were decreased in the anti-IL-1beta-treated mice. CONCLUSIONS: Anti-IL-1beta treatment suppressed pro-collagen gene expression and delayed wound healing mechanisms-properties that are likely to lead to progression of LV remodeling. In the acute phase of MI, IL-1beta appears to play a protective role.

Acute Disease↗
PubMed2001

Single oral dose of geranylgeranylacetone induces heat-shock protein 72 and renders protection against ischemia/reperfusion injury in rat heart.

BACKGROUND: Induction of heat-shock proteins (HSPs) results in cardioprotection against ischemic insult. Geranylgeranylacetone (GGA), known as an antiulcer agent, reportedly induces HSP72 in the gastric mucosa and small intestine of rats. The present study tested the hypothesis that oral GGA would induce HSP72 in the heart and thus render cardioprotection against ischemia/reperfusion injury in rats. METHODS AND RESULTS: Cardiac expression of HSPs was quantitatively evaluated in rats by Western blot analysis. Ten minutes of whole-body hyperthermia induced HSP72 expression in the rat hearts. A single oral dose of GGA (200 mg/kg) also induced expression of HSP72, which peaked at 24 hours after administration. Therefore, isolated perfused heart experiments using a Langendorff apparatus were performed 24 hours after administration of 200 mg/kg GGA (GGA group) or vehicle (control group). After a 5-minute stabilization period, no-flow global ischemia was given for 20, 40, or 60 minutes, followed by 30 minutes of reperfusion. During reperfusion, the functional recovery was greater and the released creatine kinase was less in the GGA group than in the control group. Electron microscopy findings revealed that the ischemia/reperfusion-induced damage of myocardial cells was prevented in GGA-treated myocytes. CONCLUSIONS: The results suggest that oral GGA is cardioprotective against ischemic insult through its induction of HSP72.

Administration, Oral↗
PubMed2001

Mice lacking histidine decarboxylase exhibit abnormal mast cells.

Histidine decarboxylase (HDC) synthesizes histamine from histidine in mammals. To evaluate the role of histamine, we generated HDC-deficient mice using a gene targeting method. The mice showed a histamine deficiency and lacked histamine-synthesizing activity from histidine. These HDC-deficient mice are viable and fertile but exhibit a decrease in the numbers of mast cells while the remaining mast cells show an altered morphology and reduced granular content. The amounts of mast cell granular proteases were tremendously reduced. The HDC-deficient mice provide a unique and promising model for studying the role of histamine in a broad range of normal and disease processes.

Alleles↗
PubMed2001

A C-terminal segment with properties of alpha-helix is essential for DNA binding and in vivo function of zinc finger protein Rme1p.

Rme1p plays important roles in the control of meiosis and in cell cycle progression through binding to upstream regions of IME1 and CLN2 in Saccharomyces cerevisiae. Rme1p has three zinc finger segments, and two of them are atypical. To determine DNA binding domain of Rme1p, a series of Rme1p derivatives fused with maltose-binding protein were purified and characterized by gel mobility shift assay. We show that not only three zinc fingers, but also the neighboring C-terminal region is essential for DNA binding. Mutational analysis of this region revealed that basic residues Arg-287, Lys-290, and Arg-291 and the hydrophobic residues Phe-288, Leu-292, Ile-295, and Leu-296 are critical for DNA binding. In addition, double substitutions by proline at Asn-289 and Lys-293, each of which was not essential for DNA binding, abolished DNA binding. These results suggest that the C-terminal segment forms an amphipathic helical structure. Furthermore, it was shown that the mutations in the important basic residues abolish or impair Rme1p function in vivo for repression and inhibition of spore formation. Thus, the C-terminal segment is essential and acts as a novel accessory domain for DNA binding by zinc fingers.

Amino Acid Sequence↗
PubMed2001

Effect of cadmium on gap junctional intercellular communication in primary cultures of rat renal proximal tubular cells.

Cadmium mainly accumulates in the kidney and causes renal injury. To clarify the mechanism of Cd nephrotoxicity, we investigated the effects of this element on intercellular communication through gap junction channels in primary cultures of rat renal proximal tubular cells. Sixty minutes after exposure to 100 microM Cd, dye coupling experiments showed that gap junctional intercellular communication (GJIC) was significantly inhibited. This inhibition occurred before the appearance of cytotoxicity. Intracellular calcium concentrations [Ca2+]i, which modulate the function of gap junctions, gradually increased after exposure to Cd and reached a maximum after 60 minutes. These results suggest that the inhibition of GJIC as a result of Cd exposure is related to an increase in [Ca2+]i, and that GJIC inhibition may be an indicator of nephrotoxicity.

Acetylglucosaminidase↗
PubMed2001

Microchimeric cells from the peripheral blood associated with cardiac grafts are bone marrow derived, long-lived and maintain acquired tolerance to minor histocompatibility antigen H-Y.

BACKGROUND: Although it has been well established that the microchimerism occurs in the peripheral blood of the recipients after various settings in both clinical and experimental organ transplantation, nevertheless, their roles in inducing and maintaining acquired transplantation tolerance are controversial. Furthermore, regarding the cell lineages, kinetics, and functions of the cells that constitute the microchimerism after organ transplantation, solid information is not available. METHODS: Using rat heterotopic heart isografts from bone marrow chimeras between cross-sex and applying polymerase chain reaction with specific primers to rat sex determining region of Y chromosome, a relationship between a state of microchimerism and induction as well as maintenance of acquired tolerance to H-Y antigen were examined. RESULTS: Microchimeric cells of the peripheral blood (MCPB) after cardiac grafting contain bone marrow-derived and radiation-sensitive cells. Furthermore, removal of the primary cardiac grafts revealed that microchimeric cells in the peripheral blood are long-lived cells, i.e., more than 6 months. When the female rats that had contained long-lasting MCPB, were innoculated with syngeneic male dendritic cells, failure to sensitize female toward male specific antigen H-Y was found to occur. CONCLUSIONS: Thus it was suggested that radiation-sensitive, bone marrow derived, long-lived MCPB play a significant role in maintaining acquired transplantation tolerance to minor histocompatibility antigen H-Y.

Animals↗
PubMed2001

Expression of nm23-H1 gene product in esophageal squamous cell carcinoma and its association with vessel invasion and survival.

BACKGROUND: We assessed the nm23-H1 gene product expression and its relationship with lymphatic and blood vessel invasion in patients with esophageal squamous cell carcinoma. METHODS: Formalin-fixed and paraffin-embedded tissue sections from 45 patients who were treated surgically were used in this study. Pathologists graded lymphatic and blood vessel invasion in each of the tissue samples. Expression of nm23-Hl gene product was determined using a specific monoclonal antibody. RESULTS: Expression of nm23-H1 gene product was present in 17 (37.8%) cases. We found an inverse correlation between nm23-H1 gene product expression and lymphatic vessel invasion, whereas no correlation between nm23-H1 gene product expression and blood vessel invasion. Overall survival rate was not different between nm23-H1 gene product positive and negative patients (p = 0.21). However, reduced expression of nm23-H1 gene product was associated with shorter overall survival in patients with involved lymph nodes (p < 0.05), but not in patients without involved lymph nodes (p = 0.87). CONCLUSIONS: In patients with esophageal squamous cell carcinoma, there appears to be an inverse relationship between nm23-H1 gene product expression and lymphatic vessel invasion. Furthermore, nm23-H1 gene product expression might be a prognostic marker in patients with involved lymph nodes. Our data does not demonstrate any correlation between nm23-H1 gene product expression and blood vessel invasion.

Biomarkers, Tumor↗