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Biomedical subjects

K Honda

Publications and source records attributed to K Honda.

At least 91 records · Page 5Linked to original sources

Identification of T helper cell subsets in continuous ambulatory peritoneal dialysis patients.

BACKGROUND/AIM: End-stage renal failure induces a clinical state of immunodeficiency with a higher incidence of infections and a higher mortality due to infectious complications as compared with the normal population. A crucial element in this immune response is the development of a network of cytokines. CD4-positive T helper (Th) cells differentiate into either Th1 or Th2 cells in response to various stimuli. It is important to examine whether the impaired immune responses in patients with end-stage renal disease are due to an enhanced Th1 response or a reduced number of Th2 cells. METHOD: Using a newly developed immunofluorescence staining of intracellular cytokines for flow cytometric analysis, we studied Th subsets in 24 patients on continuous ambulatory peritoneal dialysis (CAPD). RESULTS: The proportions of Th1 cells did not differ between CAPD patients (18.7 +/- 1.8%) and controls (19.6 +/- 1.5%). Unlike Th1 cells, a significantly higher proportion of CD4 cells in CAPD patients is characterized by a Th2-type cytokine secretion pattern as compared with healthy controls: 2.9 +/- 0.8% versus 1.7 +/- 0.4%. CONCLUSION: These data demonstrate that Th cells from CAPD patients manifest a dysregulated differentiation profile characterized by a major increase in the percentage of Th2 cells and by a normal percentage of Th1 cells.

Flow Cytometry↗

Soluble osteopontin and vascular calcification in hemodialysis patients.

BACKGROUND: Vascular calcification often occurs in patients with uremia. As osteopontin (OPN) is not only involved in the physiological but also the pathological calcification of tissues, OPN may be associated with the pathogenesis of aortic calcification in hemodialysis (HD) patients. METHODS: We examined the expression of OPN in atherosclerotic aortas of HD patients. In addition, we performed a prospective longitudinal study by using CT scans to detect aortic calcifications and by measuring the plasma OPN concentration by ELISA in HD patients (20 men, 16 women; mean age 55.2 +/- 21.3 years) and in healthy volunteers (18 men, 17 women; mean age 54.0 +/- 13.2 years). RESULTS: By immunohistochemical staining, OPN was abundantly localized in atherosclerotic plaques of HD patients. The macrophages surrounding the atheromatous plaques were identified as the OPN-expressing cells. We furthermore found that the concentration of soluble plasma OPN was significantly higher in HD patients as compared with the concentrations in age-matched healthy volunteers (837.3 +/- 443.2 vs. 315.1 +/- 117.4 ng/ml, p < 0.01). The OPN concentration was positively correlated with the aortic calcification index in HD patients (r = 0.749, p < 0.01). CONCLUSION: These data suggest that OPN, secreted by macrophages, plays a role in the calcification of atheromatous plaques in HD patients.

Adult↗

Expression of VLA-4 on eosinophils decreases in patients with eosinophilia.

BACKGROUND: It is assumed that the very late antigen-4 (VLA-4) plays a key role in selective migration and accumulation of eosinophils to the allergic inflammatory focus. The regulatory mechanism for VLA-4 expression is poorly understood, as is its relationship between other adhesion molecules. OBJECTIVE: The aim of the study was to elucidate the relationship between VLA-4 expression and the activation of eosinophils. METHODS: The surface expression of VLA-4, Mac-1, ICAM-1, CD4, CD25, CD69, CD89, IL-5 receptor and GM-CSF receptor on eosinophils isolated from the peripheral blood of 15 patients with eosinophilia and 16 healthy volunteers was measured. RESULTS: The surface expression of VLA-4 presented in mean fluorescent intensity by flow-cytometric analysis showed a significant decrease in the patients with eosinophilia (>700 eosinophils/microl) compared to that of the subjects without eosinophilia. On the other hand, the surface expression of Mac-1 was significantly increased in the patients with eosinophilia. There was an inverse correlation between the expression of VLA-4 and that of Mac-1 (r = -0.81) on the eosinophils obtained from the patients with eosinophilia. CONCLUSION: The changes on the surface expressions of Mac-1 and VLA-4 may be indicating the activation of eosinophils in the patients with eosinophilia and may contribute to their migration to the allergic inflammatory focus.

Adult↗

Effect of roxithromycin on eotaxin-primed reactive oxygen species from eosinophils.

BACKGROUND: The CC chemokine eotaxin not only attracts eosinophils to inflamed sites but also promotes adhesion, degranulation and reactive oxygen species production of eosinophils. Reactive oxygen species released from eosinophils are believed to injure epithelial cells at inflamed sites, resulting in airway hyperresponsiveness. Roxithromycin has been reported to have antiasthmatic effects, although its mechanism of action is not thoroughly understood. Therefore, the effect of roxithromycin on eotaxin-primed reactive oxygen species production from eosinophils was studied. METHODS: Reactive oxygen species production by eosinophils cultured with or without roxithromycin was evaluated using luminol-dependent chemiluminescence. RESULTS: Roxithromycin inhibited the release of reactive oxygen species from eosinophils evoked with the calcium ionophore A23187, regardless of pretreatment with or without eotaxin. CONCLUSION: Roxithromycin may protect epithelial cells at inflamed sites, at least partly by inhibiting the release of reactive oxygen species from eosinophils.

Adolescent↗

Involvement of phenotypes and serum levels of haptoglobin in the outcome of in vitro fertilization and embryo transfer.

Haptoglobin (Hp) possesses many functions in the immune system and angiogenesis as well as scavenging released hemoglobin, and thus it is speculated that Hp may also play a critical role in the reproductive process. To investigate the possible involvement of Hp in the outcome of in vitro fertilization and embryo transfer (IVF-ET), the serum Hp of 50 patients who underwent IVF-ET was analyzed by the Western blot method. The results showed a higher pregnancy rate in the patients with the Hp2-2 phenotype (38%) than in those with the Hp2-1 phenotype (16%) (p = 0.08), and the serum alpha 2 subunit levels in the patients who achieved pregnancy within four attempts at IVF-ET were higher than in the others (p < 0.05). The results of this study suggest that Hp is involved in the outcome of IVF-ET.

Adult↗

Transgenic rabbits expressing human apolipoprotein(a) develop more extensive atherosclerotic lesions in response to a cholesterol-rich diet.

High lipoprotein(a) [Lp(a)] levels constitute an independent risk factor for the development of atherosclerosis. However, the relationship between Lp(a) and atherosclerosis is not fully understood. To examine the effect of Lp(a) on the development of atherosclerosis, we studied transgenic rabbits expressing human apolipoprotein(a) [apo(a)], which was assembled into Lp(a) in the plasma. Human apo(a) transgenic rabbits fed a 0.3% cholesterol diet for 16 weeks had more extensive atherosclerotic lesions than did nontransgenic rabbits, although the cholesterol levels in the plasma of both groups were similarly elevated. Compared with the lesions in control rabbits, the areas of the atherosclerotic lesions in human apo(a) transgenic rabbits were significantly increased in the aorta, the iliac artery, and the carotid artery. Furthermore, human apo(a) transgenic rabbits on a cholesterol-rich diet had a greater degree of coronary atherosclerosis than did control rabbits. Immunohistochemical analysis revealed that human apo(a) was frequently deposited in the atherosclerotic lesions of transgenic rabbits. We conclude that Lp(a) may have proatherogenic effects in the setting of a cholesterol-rich diet in transgenic rabbits.

Animal Feed↗

Close association of urinary excretion of aquaporin-2 with appropriate and inappropriate arginine vasopressin-dependent antidiuresis in hyponatremia in elderly subjects.

The present study was undertaken to determine whether urinary excretion of aquaporin-2 (AQP-2) participates in the involvement of arginine vasopressin (AVP) in hyponatremia less than 130 mmol/L in 33 elderly subjects (> or =65 yr old) during the last 5-yr period. Subjects were separated into euvolemic hyponatremia groups: 13 with hypopituitarism, 8 with syndrome of inappropriate secretion of antidiuretic hormone (SIADH), 8 with mineralocorticoid-responsive hyponatremia of the elderly, and 4 with miscellaneous diseases. Approximately 40% of those with hyponatremia was derived from hypopituitarism, but severe hyponatremia was found in the patients with SIADH and mineralocorticoid-responsive hyponatremia of the elderly. Plasma AVP levels remained relatively high despite hypoosmolality and were tightly linked with exaggerated urinary excretion of AQP-2 and antidiuresis in the 3 groups of patients, except for one miscellaneous one. An acute water load test verified the impairment in water excretion, because the percent excretion of the water load was less than 42% and the minimal urinary osmolality was not sufficiently diluted. Also, plasma AVP and urinary excretion of AQP-2 were not reduced after the water load. The inappropriate secretion of AVP was evident in the patients with SIADH and hypopituitarism, and hydrocortisone replacement normalized urinary excretion of AQP-2 and renal water excretion in those with hypopituitarism. In contrast, the appropriate antidiuresis seemed to compensate loss of body fluid in the patients with mineralocorticoid-responsive hyponatremia of the elderly, who lost circulatory blood volume by 7.3% (mean). Fludrocortisone acetate increased renal sodium handling and body fluid, resulting in the reduction in AVP release and urinary excretion of AQP-2 in mineralocorticoid-responsive hyponatremia of the elderly. These findings indicate that urinary excretion of AQP-2 may be a more sensitive measure of AVP effect on renal collecting duct cells than are plasma AVP levels, and that increased urinary excretion of AQP-2 shows exaggerated AVP-induced antidiuresis in hyponatremic subjects in the elderly. In addition, mineralocorticoid-responsive hyponatremia of the elderly has to be carefully differentiated from SIADH in elderly subjects.

Aged↗

Leisure-time physical activity and other factors in relation to blood pressure in Japanese-Americans in Hawaii, USA.

To examine physical activity at work and during leisure-time as well as other factors related to blood pressure (BP) in Japanese-Americans living in Hilo, Hawaii, USA, we performed a population-based cross-sectional study with a sample of 238 participants aged 42-64 years old. This survey was carried out between 19 February and 1 March 2000 in Hilo. All participants were invited to Hilo Medical Center for a free physical examination and experimental tests including an examination of blood and urine samples. A self-administered health questionnaire was used that included items related to demographics, smoking, alcohol consumption, and habitual physical activity at work and during leisure-time. A summary score of physical activity (PA) was calculated. BP was measured using an automated BP measurement system (Khi machine, VINE Co., Ltd., Kyoto, Japan). The results showed the following. 1) Mean (SD) PA scores at work (WPA) and during leisure-time (LTPA) were 2.9 (0.5) and 2.5 (0.5) in men, and 3.0 (0.5) and 2.4 (0.3) in women, respectively; 2) Pearson correlation analyses (adjustment for age) indicated that WPA and LTPA in men show significant negative associations with SBP and DBP (p<0.05 and p<0.01), while LTPA shows significant negative associations with SBP and DBP in women (p<0.05 and p<0.01). After further adjustment for education, occupation, smoking, and alcohol consumption status, LTPA continued to show significant and negative associations with both SBP and DBP in men (p<0.01) and with DBP alone in women (p <0.01). 3) Hypertensive subjects had significantly lower mean LTPA scores than normotensive men (2.39 vs. 2.61, p<0.05) and women (2.32 vs. 2.45, p<0.05). 4) Body mass index and the ratio of sodium to potassium excretion showed significant and positive associations with SBP and DBP in multiple linear regression analyses. In conclusion, the results further emphasize that the health benefits of LTPA, control of body weight, and reduction in salt intake should continually receive strong attention in population-based high BP control.

Adult↗

Proinflammatory cytokines regulate the gene expression of hyaluronic acid synthetase in cultured rabbit synovial membrane cells.

To elucidate the mechanism of accumulation and fragmentation of hyaluronic acid (HA) under inflammatory conditions, we investigated the effect of proinflammatory cytokines on hyaluronic acid synthetase (HAS) mRNA expression using cultured rabbit synovial membrane cells. HASs mRNA levels were determined by real-time PCR. HAS2 mRNA expression was maximally enhanced 3.3- and 2.8-fold after 3-hour stimulation with IL-1beta (1 ng/ml) and after 1-hour stimulation with TNF-alpha (10 ng/ml). HAS3 mRNA expression was increased by a maximum of 4.3 times after 3-hour stimulation with IL-1beta (10 ng/ml), whereas 1-hour stimulation with TNF-alpha (10 ng/ml) and IFN-gamma (10 ng/ml) induced around a 2.5-fold increase in HAS3 mRNA. Although IFN-gamma (1-100 ng/ml) alone showed little effect on HAS2 mRNA expression, the effect was synergized by combined with both IL-1beta and TNF-alpha, substantially increasing HAS2 mRNA expression. These results suggest that proinflammatory cytokines regulate the HAS expression, and consequently may contribute to the accumulation and fragmentation of HA.

Animals↗

Expression and distribution of cyclooxygenase-2 in human periovulatory ovary.

Cyclooxygenase, which converts arachidonic acid into prostaglandins, has two types of isoforms, cyclooxygenase-1 and cyclooxygenase-2 (COX-2). The latter is thought to be essential for the ovulatory mechanism. However, expression or distribution of COX-2 in periovulatory human ovary has not been reported. The aim of our study was to examine COX-2 expression and distribution in pre- and postovulatory human ovary. COX-2 was detected by Western blot analysis of pre-ovulatory human ovarian follicular fluid. The levels of COX-2 in preovulatory fluid obtained from 20 subjects underwent in vitro fertilization and embryo transfer, and were assayed using enzyme immunoassay for human COX-2. The results showed 7.3+/-4.1 ng/ml (mean +/- SD) with a COX-2 level range of 2.7 to 19.5 ng/ml of follicular fluid. Detection of COX-2 is considered to reflect its production in the preovulatory follicle. Immunofluorescence microscopic examination of an ovary obtained from a woman at the postovulatory period showed distribution of COX-2 in interstitial but not in granulosa cells in a ruptured follicle. These findings collectively suggest the possibility that COX-2 is mainly produced in follicles in a preovulatory phase, while after ovulation, COX-2 is produced in interstitial cells in human ovary.

Adult↗

An antibody against anemia-inducing substance inhibits cation influx in red blood cells from cancer patients.

Resealed ghost of red blood cells (RBCs) from advanced cancer patients includes proteins with antigenicities common to an anemia-inducing substance that we separated from plasma of patients with advanced malignant neoplasms. Although cation influx in vitro in RBCs from a cancer patient is larger than that from a normal healthy volunteer, an antibody against anemia-inducing substance inhibited the in vitro cation influx in RBCs from the cancer patient. Activation of the cation influx with N-ethylmaleimide after reaction with the antibody reversed the effect to create a greater cation influx in RBCs from the patient, as compared with that from the healthy volunteer.

Anemia↗

Pesticide poisoning initially suspected as a natural death.

A pesticide poisoning victim suspected initially as having died a natural death was autopsied. The victim was a 47-year-old male. Macroscopically, signs of acute death and, in particular, general erosion in the mucosa of the airways and esophagus were observed. In the gastric contents, which had a pungent smell and a greenish-brown color, 5.00 g/L of propanil, 1.27 g/L of carbaryl, 0.38 g/L of ethylbenzene, and 0.32 g/L of xylene were detected. In the blood (serum), 21.6 mg/L of propanil, 8.1 mg/L of carbaryl, 1.7 mg/L of ethylbenzene, and 4.0 mg/L of xylene were identified. Postmortem methemoglobinemia (45%) was recognized. The cause of death was considered to have been pesticide poisoning; propanil was probably most responsible for his death. The police considered the case to be "death with illness as the suspected cause." By performing an autopsy, however, we were able to clarify that the cause of death was pesticide poisoning.

Carbaryl↗

Atomic resolution structure analysis of beta' polymorph crystal of a triacylglycerol: 1,2-dipalmitoyl-3-myristoyl-sn-glycerol.

The crystal structure of the beta'-2 form of a mixed chain triacylglycerol (TAG), 1,2-dipalmitoyl-3-myristoyl-sn-glycerol (PPM), was determined to a final reliability factor of 0.074. This work is the first to resolve the atomic-level structure of the beta' polymorph, which is of the highest functionality among multiple polymorphs in asymmetric TAG. In particular, fat crystals present in food emulsions are in beta', whose transformation into beta causes deterioration in their physical properties. beta'-2, one of the two beta' forms of PPM, forms a monoclinic unit cell with a space group of C2; Z = 8, a = 16.534(5) A, b = 7.537(2) A, c = 81.626(9) A; beta = 90.28(2) degrees, V = 10171(3) A(3), density = 1.018 g/cm(3), and mu = 4.96 cm(-1). The following characteristics were obtained: 1) two asymmetric units, named A and B, form a hybrid-type orthorhombic perpendicular subcell; 2) the two asymmetric units reveal different glycerol conformations: trans for sn-1 palmitic acid and sn-2 palmitic acid, but gauche for sn-3 myristic acid in A; and trans for sn-2 palmitic acid and sn-3 myristic acid, but gauche for sn-1 palmitic acid in B; 3) a unit lamellae reveals a four-chain-length structure consisting of two double-layer leaflets; 4) the two double-layer leaflets are combined end-by-end in a unit lamellae; and 5) the chain axes are alternatively inclined against the lamellar interface. -- Sato, K., M. Goto, J. Yano, K. Honda, D. R. Kodali, and D. M. Small. Atomic resolution structure analysis of beta' polymorph crystal of a triacylglycerol: 1,2-dipalmitoyl-3-myristoyl-sn-glycerol. J. Lipid Res. 2001. 42: 338--345.

Calorimetry, Differential Scanning↗

Metachromasia of the endocervical epithelium for delineating the internal os.

OBJECTIVE: To study the metachromatic stainability of the endocervical epithelium. STUDY DESIGN: Surgical specimens that included endocervical epithelium were deparaffinized and stained with toluidine blue at various pH levels and after enzyme digestion. Glycosaminoglycans were separated from endocervical tissue and analyzed by electrophoresis. RESULTS: The endocervical epithelium stained metachromatically purple with toluidine blue in pH 4.1 buffer, but the staining disappeared after chondroitinase digestion. The electrophoretic mobility of the glycosaminoglycan fraction separated from the endocervical epithelium was compatible with nonsulfated chondroitin. CONCLUSION: Endocervical epithelium was identifiable from metachromatic staining below the internal os, and the electrophoretic results of the tissue extract suggested that nonsulfated chondroitin is the main component of glycosaminoglycans in endocervical epithelium.

Cervix Uteri↗

Antiasthmatic effect of YM976, a novel PDE4 inhibitor, in guinea pigs.

YM976 is a novel and specific phosphodiesterase 4 inhibitor. In our previous report, we indicated that YM976 has less emetogenicity, a major adverse effect of PDE4 inhibitors, than rolipram. In the present study, we examined the antiasthmatic effects of YM976 in guinea pigs. YM976 orally administered exhibited inhibition of antigen-induced bronchoconstriction, airway plasma leakage, airway eosinophil infiltration, and airway hyperreactivity (AHR), with ED(50) values of 7.3, 5.7, 1.0, and 0.52 mg/kg, respectively. Rolipram also dose dependently suppressed these responses. Prednisolone suppressed eosinophil infiltration and AHR, whereas it failed to inhibit bronchoconstriction and plasma leakage. Theophylline moderately suppressed bronchoconstriction and edema, but neither eosinophil infiltration nor AHR. YM976 suppressed the peroxidase activity in the bronchoalveolar lavage fluid, and elevated the intracellular peroxidase activity and cAMP contents of infiltrated cells, suggesting that YM976 inhibited not only the infiltration but also the activation of leukocytes. In vitro studies revealed that YM976 potently suppressed eosinophil activation (EC(30) = 83 nM), and exerted a little relaxation on LTD(4)-precontracted tracheal smooth muscle (EC(50) = 370 nM). Rolipram exhibited a potent tracheal relaxation activity (EC(50) = 50 nM). In vivo studies indicated that the inhibitory effect of YM976 on LTD(4)-induced bronchospasm was marginal even at 30 mg/kg p.o., although rolipram significantly inhibited the bronchospasm at the same dose. These results suggested that YM976, unlike rolipram, showed the inhibition of antigen-induced airway responses due to anti-inflammatory effects, but not to direct tracheal relaxation. In conclusion, YM976 may have potential therapeutic value in the treatment of asthma through its anti-inflammatory activities.

Animals↗

[The voiding after the suburethral sling operation, obstructive or non-obstructive?].

To examine whether or not the suburethral sling operation produces obstruction during voiding, seven females who underwent the sling operation using synthetic material (Vesica Sling Kit) were studied postoperatively urodynamically. Uroflowmetry and residual urine measurement showed no overt voiding difficulties in any cases. However, in one case, a pressure flow study indicated equivocal and the position of the sling material was judged to be too proximal by fluoroscopic monitoring. In all other 6 cases pressure flow was shown to be non-obstructive. Fluoroscopic finding also demonstrated in these 6 cases an appropriate bladder neck opening at the time of voiding and the sling was positioned just from the bladder neck to mid-urethra. Thus, it is concluded that the suburethral sling operation produces no obstruction as long as the position of the sling material is carefully determined from bladder neck to mid-urethra and excessive tension is avoided.

Aged↗

Identifying sex chromosome abnormalities in forensic DNA testing using amelogenin and sex chromosome short tandem repeats.

Forensic DNA laboratories worldwide have begun using multiplexed STR systems to decrease analysis time and increase sample throughput. The loci used in these systems are basically "nonsense" regions of human DNA. However, due to the chromosome on which some of these loci are located, various genetic abnormalities can sometimes be detected. This paper will show one such abnormality--Klinefelter's Syndrome--and the process used to show the possibility of this defect in two undiagnosed males using peak height ratios at the Amelogenin locus, and X-Y STRs.

Amelogenin↗

Evaluation of prognostic factors for myeloperoxidase anti-neutrophil cytoplasmic antibody- (MPO-ANCA) associated glomerulonephritis.

AIMS: To identify prognostic factors for myeloperoxidase anti-neutrophil cytoplasmic antibody- (MPO-ANCA) associated glomerulonephritis. MATERIALS: We analyzed the relations between the clinical and histological features of MPO-ANCA-associated glomerulonephritis and clinical outcome in 14 patients with the disease. The patients were divided into two groups: group 1 consisted of 5 patients with progressive deterioration of renal function leading to end-stage renal disease or chronic dialysis, group 2 consisted of 9 patients in whom the initial deterioration of renal function had improved by the time of the final examination. RESULTS: Creatinine clearance at the time of biopsy was significantly lower in group 1 than in group 2, and urinary protein was higher. The mean interval between onset of symptoms and biopsy in both groups was almost the same. Recovery of renal function was correlated with the percentage of global sclerosis, but patients who had severe crescent formation did not always have a poor response to steroid therapy. There was no statistical difference between the two groups in treatment regimens. Four patients required hemodialysis at the time of biopsy (3 in group 1 and 1 in group 2). Plasmapheresis was performed in 5 patients (1 in group 1 and 4 in group 2). CONCLUSIONS: Degree of proteinuria and renal dysfunction are indicators of a poor prognosis in MPO-ANCA-associated glomerulonephritis. Global sclerosis is a histological feature that is an indicator of a poor prognosis, whereas cellular crescent formation is a predictor of a good response to steroid therapy.

Adult↗