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C Yasunaga

Publications and source records attributed to C Yasunaga.

At least 19 recordsLinked to original sources
PubMed2000

Transforming growth factor-beta is involved in the pathogenesis of dialysis-related amyloidosis.

BACKGROUND: Advanced glycation end product-modified beta2-microglobulin (AGE-beta2m) is an important component of dialysis-related amyloidosis (DRA). Its presence induces monocyte chemotaxis and the release of the proinflammatory cytokines through macrophage activation. Transforming growth factor-beta (TGF-beta) is a multifunctional cytokine that also has chemotactic activity for monocytes at very low (0.1 to 10 pg/mL) concentrations and inhibits proinflammatory cytokine production of macrophages. In this study, we investigated the role of TGF-beta in the pathogenesis of DRA. METHODS: We performed an immunohistochemical study of DRA tissues (8 cases) to confirm the existence of TGF-betas and their receptors; we also performed a chemotaxis assay of human monocytes as well as enzyme-linked immunosorbent assay (ELISA) of TGF-beta1, tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and interleukin-1 receptor antagonist (IL-1Ra) in the supernatant of human monocyte-derived macrophage cell culture under varying conditions of incubation with TGF-beta1, AGE-beta2m, and TGF-beta1 antibody additions. RESULTS: There was positive staining for TGF-betas (types 1, 2, and 3) and their receptors (types I, II, and III) in infiltrated macrophages (CD68+), synovial lining cell, as well as vascular walls around amyloid deposition. AGE-beta2m also induced TGF-beta1 production by macrophages in a dose-dependent manner (410 +/- 80 pg/mL at 12.5 microg/mL, 621 +/- 62 pg/mL at 25 microg/mL, and 776 +/- 62 pg/mL at 50 microg/mL of AGE-beta2m). AGE-beta2m induced significant TNF-alpha and IL-1Ra production by macrophage. The addition of exogenous TGF-beta1 (0.1 to 10 ng/mL) decreased AGE-beta2m-induced TNF-alpha production and increased IL-1Ra production in a dose-dependent fashion. IL-1beta production was not effected by any experimental conditions. In chemotaxis assay, anti-TGF-beta1 antibody (0.1 to 10 microg/mL) attenuated AGE-beta2m-induced monocyte chemotaxis. CONCLUSIONS: These results provide the first evidence to our knowledge for the presence of TGF-beta in DRA tissue, as well as the stimulatory action of AGE-beta2m on tissue macrophages. In turn, TGF-beta suppresses the proinflammatory activation of macrophages, suggesting a dual role for TGF-beta in the inflammatory process of DRA. These observations may provide a pathophysiologic link between TGF-beta and DRA.

Aged↗
PubMed1999

Effects of a parathyroidectomy on the immune system and nutritional condition in chronic dialysis patients with secondary hyperparathyroidism.

BACKGROUND: Parathyroid hormone (PTH) has an adverse effect on the immune system and may cause immunologic disorders in patients with chronic renal failure. The in vivo effects of a parathyroidectomy on the immunologic parameters was examined. METHODS: Thirty-four patients under dialysis therapy received a parathyroidectomy (PTx) for secondary hyperparathyroidism (HPT). They were prospectively studied regarding serum immunoglobulins, complements, CD markers, and serum soluble IL-2 receptor (sIL-2R) until 12 months after PTx. RESULTS: The serum levels of IgG, IgA and IgM showed significant increase until 12 months after PTx (P<0.001, respectively). C3, C4, and CH50 also indicated significant increase at 12 months after PTx. In cellular immunity, only serum sIL-2R showed significant increase 2 weeks after PTx (P = 0.028). The hematocrit and serum albumin also improved significantly at 12 months. CONCLUSIONS: PTx showed beneficial effects on humoral immunological markers. The effects are probably due to the remarkable PTH reduction and partly improved nutritional state after PTx.

Adult↗
PubMed1998

Early development of Epstein-Barr virus-associated T-cell lymphoma after a living-related renal transplantation.

We herein report a case of Epstein-Barr virus (EBV)-associated T-cell lymphoma that developed within a month after a kidney transplantation. The recipient was a 37-year-old man who had evidence of a previous EBV infection. Cyclosporine, methylprednisolone, and azathioprine were used for immunosuppression, and acute rejection was treated with high-dose methylprednisolone. The lactate dehydrogenase level started to increase on day 24 and thereafter peaked on day 37 while also demonstrating progressive jaundice and a bleeding tendency. A transplant nephrectomy was done on day 37; however, the patient could not recover and eventually died of respiratory failure as a result of diffuse pulmonary edema. A pathological examination of the resected kidney revealed a diffuse proliferation of large atypical lymphoid cells in the parenchyma. Immunohistochemically, the tumor cells were positive for CD45 and T-cell marker, CD45RO, but negative for B-cell markers. EBV-encoded RNA was demonstrated within the neoplastic cells by in situ hybridization.

Adult↗
PubMed1998

Properties of a new picorna-like virus of the brown-winged green bug, plautia stali

A picorna-like virus was isolated from the brown-winged green bug, Plautia stali. The virus was named Plautia stali intestine virus (PSIV) based on the multiplication site of the virus in the infected insects. PSIV is a spherical particle with a diameter of 30 nm. Particles of PSIV were found to contain a 9.1-kb single-stranded RNA. Polyacrylamide gel electrophoresis of purified PSIV particles revealed three major (33, 30, 26 kDa), one medium (35 kDa), and one minor (4.5 kDa) structural proteins. The molar ratios of the proteins suggested that the 35-, 33-, 30-, 26-, and 4.5-kDa proteins corresponded to VP0, VP1, VP2, VP3, and VP4 of vertebrate picornaviruses. Immunological assays indicated that PSIV and Nezara viridula virus-1, which is a picorna-like virus of the green stinkbug in South Africa, were serologically distinct. PSIV was detected in the intestine with enzyme-linked immunosorbent assay but not in the salivary glands, fat bodies, Malpighian tubules, and reproductive organs of viruliferous P. stali. The virus was also detected on the surface of the eggs and in the feces of infected insects. These results suggest that excrement of infected insects are the primary inoculum of the virus in a colony of P. stali. The nonviruliferous adults of P. stali usually survive a few months in laboratory, while the average of adulthood lifetime in viruliferous P. stali was about 13 days. PSIV also infected two other stinkbugs, Nezara viridula and Halyomorpha halys. Copyright 1998 Academic Press.

Journal Article↗
PubMed1998

Coinfection of Spodoptera exigua and Spodoptera frugiperda cell lines with the nuclear polyhedrosis viruses of Autographa californica and Spodoptera exigua.

The Autographa californica multinucleocapsid nuclear polyhedrosis virus (AcMNPV) has a broad host range among Lepidoptera. In contrast, the Spodoptera exigua MNPV (SeMNPV) can replicate efficiently only in S. exigua larvae or S. exigua-derived cell lines. In this study, we examined the coinfection of S. exigua Se301 and Spodoptera frugiperda IPLB-SF21AEII (Sf21) cell lines with SeMNPV and AcMNPV recombinant (Ac360-501beta-gal) which was constructed for expression of beta-galactosidase under control of the polyhedrin promoter. Coinfection led to the restriction as the level of late gene expression, nonoccluded virus production, and DNA replication of Ac360-501beta-gal in both Se301 and Sf21 cell lines. In contrast, Ac360-501beta-gal supported the SeMNPV replication in Sf21 cells. Occurrence of recombinants, between Ac360-501beta-gal and SeMNPV, with expanded host range was not observed in coinfected Sf21 cells. This suggests that Ac360-501beta-gal supports the SeMNPV replication through trans-activation.

Animals↗
PubMed1998

Replication of Spodoptera exigua nucleopolyhedrovirus in permissive and non-permissive lepidopteran cell lines.

The Spodoptera exigua multinucleocapsid nucleopolyhedrovirus (SeMNPV) was inoculated to eight lepidopteran cell lines derived from Spodoptera exigua (Se301), Spodoptera frugiperda (SF21AEII), Spodoptera littoralis (CLS-79), Spodoptera litura (SpLi-221), Pseudaletia separata (LeSe-11), Trichoplusia ni (hi-5), Plutella xylostella (PXL/C) and Bombyx mori (BmN4). The productive infection of SeMNPV was observed only in Se301 cells. However, a dot-blot hybridization analysis revealed that SeMNPV DNA replicated in five non-permissive cell lines: SF21AEII, CLS-79, SpLi-221, hi-5 and BmN4. In addition, the virus-infected hi-5 and BmN4 cells displayed morphological changes. In contrast, CLS-79 cells inoculated with SeMNPV showed membrane blebbing at 20 hrs post inoculation (p.i.) and fragmentation of genomic DNA. All that indicated that the infected CLS-79 cells underwent apoptosis. These findings indicate that the SeMNPV replication was restricted at various points in dependence upon each cell line.

Animals↗
PubMed1998

Echocardiographic evaluation in long-term continuous ambulatory peritoneal dialysis compared with the hemodialysis patients.

In dialysis patients, the prevalence of severe left ventricular (LV) hypertrophy and systolic failure, important predictors of cardiovascular morbidity and mortality, has been reported to be very high. Therefore, we investigated cardiac function in 17 long-term CAPD patients (dialysis duration: 76.5 +/- 13.2 months; L-CAPD) by echocardiography and pulsed Doppler, and then compared with 16 short-term CAPD patients (dialysis duration: 28.9 +/- 11.9 months; S-CAPD), 21 long-term hemodialysis patients (dialysis duration: 165.1 +/- 52.7 months; L-HD), and 22 short-term hemodialysis patients (dialysis duration: 71.3 +/- 28.9 months; S-HD), except for the cases with diabetes mellitus, ischemic heart disease, cardiac surgery or overt congestive heart failure. We selected 13 normotensive patients with normal kidney function as normal control group matched for sex and age (Control). Concerning with L-CAPD, S-CAPD, L-HD, and S-HD, these four groups were matched for age and original diseases. We examined blood pressure (BP), cardiothoracic rate (CTR), antihypertensive (AHT) drugs and laboratory data. Wall thickness, left atrium, ventricular chamber size, ejection fraction (EF) and left ventricular mass (LV mass) [Devereux et al. 1986] were measured by echocardiograph. Peak early diastolic flow velocity (E), peak atrial filling velocity (A), A/E ratio and deceleration time of peak early diastolic flow velocity (DT) were calculated by analyzing transmitral flow, recorded by pulsed Doppler. BP control, CTR and EF were significantly worse in L-CAPD than in other patient groups. A/E as one of parameters for cardiac diastolic function was significantly higher in L-CAPD than in HD patients. LVMI (LV mass index: LV mass/body surface area) was significantly higher in L-CAPD than in other groups. LVMI in CAPD patients was shown to be significantly worse as time goes. Volume control by itself without AHT drugs could achieve good BP control in the long-term CAPD patients who were changed to maintenance hemodialysis because of peritoneal sclerosis. We concluded that LV hypertrophy and systolic dysfunction tend to progress in CAPD patients as time goes on. Also it is suggested that the cause of cardiac dysfunction in CAPD patients was mainly based on poor BP control probably due to overhydration, and therefore, appropriate volume control in CAPD patients is especially important.

Antihypertensive Agents↗
PubMed1998

Acute renal failure due to hypokalemic rhabdomyolysis in Gitelman's syndrome.

A 46-year-old-male developed acute renal failure (ARF) secondary to hypokalemic rhabdomyolysis. Potassium supplementation restored renal function following improvement of the rhabdomyolysis. After recovery from ARF, further evaluation disclosed he had hypokalemic metabolic alkalosis, normotensive hyperreninemia, hyperaldosteronism, renal hypomagnesemia, hypocalciuria and hyperplasia of the juxtaglomerular apparatus which are a diagnostic set of disorders in Gitelman's syndrome, a variant of Bartter's syndrome. This is the first reported case of ARF due to hypokalemic rhabdomyolysis associated with Gitelman's syndrome.

Acute Kidney Injury↗
PubMed1997

Laparoscopic splenectomy for splenic hamartoma.

Advances in imaging techniques have made pre-operative diagnosis of splenic tumors possible. A case of successful laparoscopic splenectomy for splenic hamartoma is described here and the indications of this technique are discussed.

Hamartoma↗
PubMed1997

Dialysis-related amyloidosis of the tongue in long-term hemodialysis patients.

Dialysis-related amyloidosis (DRA) predominantly occurs in the osteoarticular structures. However, according to studies in the increasing number of long-term hemodialysis patients, DRA has also been systemically found to appear in the other tissues and organs as well. In this study, we investigated lingual amyloidosis in relation to systemic DRA. A total of 472 patients were studied who were on regular hemodialysis for more than 10 years, including 103 patients for more than 20 years. Eight of these patients (7 males and 1 female, mean age 59 +/- 8 years, range 46 to 68 years) developed lingual amyloidosis, seemingly as a result of beta2-microglobulin (beta2m) deposits. All patients demonstrating lingual amyloidosis had been treated with regular hemodialysis for more than 20 years (mean HD duration 23.6 +/- 1.4 years), and its morbidity was 7.8% in the 103 patients and 20% (6 patients) in the 30 patients treated for more than 23 years with hemodialysis. Hemodialysis (HD) duration with bioincompatible unsubstituted cellulose membranes in the 8 patients was longer than that in the control group without lingual amyloidosis (P < 0.05). Lingual amyloid nodules were whitish-yellow in color and varied in size, at least over 1 mm in diameter. Their consistency was firmer than the intact tongue. The location of the amyloid nodules could be classified into two types: (1) diffuse type (diffusely distributed over the tongue), and (2) lateral type (localized only in the lateral side of the tongue). Five of the eight patients with lingual amyloidosis complained of functional disturbances in the tongue, such as abnormal taste, or difficulty in mobility and articulation. No macroglossia was observed in any of these cases. It was thus concluded that DRA of the tongue is a very rare complication, occurring in the late stage of long-term hemodialysis patients, that disturbs their quality of life.

Adult↗