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Biomedical subjects

N Kashihara

Publications and source records attributed to N Kashihara.

At least 55 records · Page 3Linked to original sources

Influence of hypophysectomy on renal proteoglycans and their modulation by insulin-like growth factor-I and its receptor.

Hypophysectomy leads to growth retardation of the animals, which is believed to be related to the deficiency of certain growth factors influencing the metabolism and synthesis of glycoproteins. Conceivably, the extracellular matrix proteins (ECM) are also affected, in particular the sulfated proteoglycans (PGs). In this study, we investigated the status of the ECM proteins and sulfated PGs, and the expression and de novo synthesis of insulin-like growth factor-I (IGF-I) receptor (IGF-IR) in hypophysectomized (Hx) rats. The studies were extended to ascertain the effect of IGF-I on the de novo synthesis of glomerular ECM glycoproteins in Hx rats. An organ perfusion system was used in which isolated rat kidneys were radiolabeled with either [35S]sulfate or [35S]methionine, after which IGF-IR and ECM macromolecules were isolated and characterized by biochemical and tissue autoradiographic procedures. Hypophysectomy resulted in a fall in IGF-I levels in serum and isolated renal glomeruli. Reduced synthesis of ECM proteins, i.e. type IV collagen, laminin, and sulfated PGs, and reduced synthesis and mRNA expression of IGF-IR were observed in the glomeruli of the Hx rats. Tissue autoradiographic studies revealed a reduced grain density (concentration of radiation) over various cell types of the glomerulus. After inclusion of IGF-I in the perfusion medium not only was synthesis restored to normal in Hx rats, but it far exceeded the control basal values in the intact animals. Under the influence of IGF-I, the magnitude of increased synthesis of the ECM proteins, in particular the sulfated PGs, was highly accentuated in the kidneys of the Hx group compared to the controls. Also, a remarkably increased [35S]sulfate incorporation was observed in the glomerular mesangial cells. The analysis of IGF-IR by specific binding studies revealed a decreased concentration of the receptors, but an increased IGF-I-binding affinity, the latter of which probably contributed to the IGF-I-induced accentuated synthesis of renal glomerular PGs in the Hx group.

Animals↗

Clinical significance of necrosis in lupus nephritis.

The significance of necrosis (karyorrhexis), among the most characteristic findings in lupus nephritis, was evaluated by studying the correlation between the existence of necrosis in renal biopsy specimens and laboratory findings. The subjects were 54 patients with diffuse proliferative lupus nephritis and 6 patients with focal proliferative lupus nephritis selected from 143 patients with lupus nephritis. We also compared the clinical course of oral prednisolone and intravenous methylprednisolone pulse therapies after steroid administration. Compared with the non-necrosis group, the necrosis group had significantly lower CH50 levels and more proteinuria. Patients with necrosis were effectively treated with repeated pulse therapy judging by immunological activity and the decrease in proteinuria at an early stage, but responded poorly to oral steroid therapy. As the presence of necrosis in cases of lupus nephritis means high immunological activity of the lesion and there is responsiveness to a large dose of steroids, extensive immunosuppressive therapy including methylprednisolone pulse therapy should be applied to these patients.

Administration, Oral↗

[Clinical study of primary hyperparathyroidism--diagnosis, parathyroidectomy and late result of operation].

We retrospectively studied clinical problems for 55 patients with primary hyperparathyroidism who were operated on at our hospital. The chance to discovery of primary hyperparathyroidism and its accompanied symptoms were various. Other than classical symptoms, hypertension was noted in 12 patients and malignant tumors in 9. Forty-four percent of patients who had no bone related symptoms were found to have decreased bone mineral density (BMD). Even the patients with normal BMD were seen to increase the BMD, postoperatively. We thought that the parathyroidectomy was indicated for the asymptomatic patients with normal BMD. Biochemical investigation showed that positive rate were 50% for PTH-C, 94% for PTH-HS, 78% for intact PTH, 87% for serum total calcium and 98% for serum ionized calcium. Serum ionized calcium and intact PTH were useful for the diagnosis of patients who had normocalcemia or slight elevation of serum calcium. The sensitivity was 61% for ultrasound sonography (US) and 49% for computer tomography (CT) and scintigram, respectively. The detection rate of US and CT was positively related to the size of the parathyroid glands, but scintigram was not. The rate with which the parathyroid glands can be recognized during operation increased from 30% in the former group to 52% in the later group. As a result, 11% of the patients with adenoma had too much surgery and 29% of the patients with hyperplasia had too little surgery.

Adult↗

[Endocrine chemotherapy for prostatic cancer].

We carried out a randomized joint study on endocrine therapy and endocrine chemotherapy for prostatic cancer at our department and 17 affiliated institutions. Of 80 patients entered, 39 patients were treated with chlormadinone acetate alone (group A) and 41 patients were treated with chlormadinone acetate in combination with UFT (group B). After excluding 10 inappropriate patients, Stage C was observed in 14 patients in group A and 13 in group B, and stage D in 20 patients in group A and 23 in group B. Side effects were observed in 8.8% (3/34) in group A and 22.2% (8/30) in group B without a significant difference. The anti-tumor effects (response rate) and clinical effects with respect to each item did not significantly differ between the two groups. The non-recurrence rate and survival rate were significantly higher in group B than in group A. These findings suggest the usefulness of endocrine chemotherapy using UFT.

Antineoplastic Combined Chemotherapy Protocols↗

Expression of mRNA's of cytokines and growth factors in experimental glomerulonephritis.

A variety of cytokines and growth factors have been recently shown to modulate the growth of mesangial cells and the synthesis of the mesangial matrix. We examined chronological change of mRNA expression of interleukin-1 beta (IL-1 beta), tumor necrosis factor-alpha (TNF-alpha), transforming growth factor beta 1 (TGF-beta 1), and the platelet-derived growth factor (PDGF)-B chain in glomeruli of nephrotoxic serum nephritis using reverse transcription and the polymerase chain reaction (RT-PCR) method. Expression of TNF-alpha mRNA increased immediately after induction of nephrotoxic serum nephritis. Levels of IL-1 beta and PDGF-B chain mRNAs increased at 24 hr and remained elevated for 4 weeks. TGF-beta 1 mRNA expression increased significantly at 24 hr, peaking at 2 weeks. The chronological changes of these cytokines and growth factors were associated with two phases of inflammation in this model. Among them, expression of PDGF-B chain mRNA preceded mesangial proliferation and expression of TGF-beta 1 preceded accumulation of mesangial matrix, indicating that these two growth factors contributed to these histological alterations.

Animals↗

In vitro micro-autoradiography of atrial natriuretic peptide in biopsy specimens from patients with renal diseases.

We investigated the localization and density of atrial natriuretic peptide (ANP) receptors in human renal biopsy specimens by using in vitro micro-autoradiography (ARG) of [125I]-alpha-human (1-28) ANP. In a preliminary study, we measured the effect of storing tissue samples on ANP binding, using in vitro micro-ARG of Wistar rat kidney under optimal conditions. Duration of the preservation period did not affect ANP binding to renal tissue until samples had been stored at -30 degrees C for two years. A total of 11 human renal tissues were used to assay binding of ANP-ARG, including normal tissue obtained after nephrectomy because of renal cancer. ANP binding occurred predominantly within the glomerulus and, to a lesser extent, in the tubular region both in rat kidney sections and in human renal biopsy specimens. The density of ANP binding, calculated by counting grains in fixed areas, was compared with normal and pathological tissues. The density of grains tended to decrease in patients with renal dysfunction and hypertension except for one case of IgA nephropathy with normal renal function and blood pressure. The density of grains increased in a patient with nephrogenic diabetes insipidus. In the present study, we have established a method that uses in vitro micro-ARG for assessing ANP binding in human biopsy specimens.

Animals↗

[Effect of heparin and low-molecular-weight heparin on proliferative glomerulonephritis].

Effect of heparin and low-molecular-weight heparin (LMWH) were evaluated on 15 patients with proliferative glomerulonephritis with various degrees of sclerosing legion. Five cases were subcutaneously administered with 7000 to 11000 units of heparin for 4 weeks. Ten cases were administered with 60 unit/kg of LMWH by drip infusion for 4 weeks. Eleven cases were treated with prednisolone and all cases were treated with anti-platelet agent as well. Urinary protein excretion reduced from 3.0 +/- 1.8 to 1.8 +/- 0.6 g/day in the heparin-treated group and from 2.4 +/- 1.9 to 1.8 +/- 1.4 g/day in the LMWH-treated group, respectively. There were no remarkable changes in the renal functions of both groups. In one case, both heparin and LMWH brought about reduction of proteinuria. Therefore, LMWH reduced urinary protein excretion by the same mechanism as heparin. The LMWH has an advantage over heparin in that the former has less risk of causing bleeding. We conclude that heparin and LMWH reduce proteinuria in some patients with proliferative glomerulonephritis. The LMWH is beneficial in the treatment of proliferative glomerulonephritis with a sclerosing lesion.

Adolescent↗

Alteration of renal receptors for atrial natriuretic peptide and vasopressin in spontaneously hypertensive rats treated with antihypertensive diuretics.

To investigate the alteration of the renal atrial natriuretic peptide (ANP) and arginine vasopressin (AVP) receptors in the controlled hypertensive state of spontaneously hypertensive rat (SHR) treated with antihypertensive diuretics, 12 weeks old SHRs were administered an antihypertensive diuretic, furosemide, trichloromethiazide, or indapamide, daily for 10 days and investigated by radiolabeled receptor assay (RRA) of ANP and AVP. The urine volume was significantly increased in all groups treated with antihypertensive diuretics as compared with the untreated control group on day 3. Systolic blood pressure was significantly decreased in groups treated with both trichloromethiazide and indapamide. The number of renal ANP receptors decreased; affinity was increased only in the SHR administered indapamide. The affinity of the renal AVP receptor was also decreased in that group. Alteration of ANP and AVP receptors was observed only in the group treated with indapamide. This indicates that the ANP and AVP receptor in the kidney of SHR was changed not only by diuresis or reduction of blood pressure, but by the pharmacological action of indapamide.

Animals↗

Study of glomerular permselectivity for proteins of the glomerular basement membrane using a dialyzer model.

The glomerular basement membrane (GBM) is considered to regulate glomerular permselectivity for proteins by acting as both size barrier and charge barrier. Since heparan sulfate-proteoglycan (HS-PG), which forms the charge barrier of GBM, contains a sulfonic acid, we made membranes with various degrees of negative charge models of GBM by addition of sulfonic acid to ethylene vinyl alcohol (EVAL) membranes. A high-resolution scanning electron-microscopic study revealed no ultrastructural alterations after adding sulfonic acid to EVAL membranes. Both neutrally and negatively charged membranes had porous structures in the inner surface of the membranes. The interrelation between the two actions of size and charge of GBM was studied using special dialyzers with various degrees of negative charge and different pore sizes. The negatively charged membranes adsorbed proteins with positive charge and repulsed proteins with negative charge. The degrees of adsorption and repulsion were weaker in membranes with larger pores and were stronger for proteins with larger molecular weights. The permselectivity for proteins of a charged membrane depends largely upon the interrelation between the pore size of the membrane and the size of the proteins. It is, therefore, suggested that the presence of a size barrier in GBM is necessary for the charge barrier to effectively exert glomerular permselectivity for proteins. Our study may lead to the development of a dialyzer with higher permselectivity by adding sulfonic acid rather than conventional dialyzers.

Basement Membrane↗

A study on cross-reactivity of anti-DNA antibody with glycosaminoglycans.

To study the pathogenesis of lupus nephritis, the cross reactivity between anti-DNA antibody and glycosaminoglycans (GAGs) was investigated. Monoclonal anti-DNA antibodies were obtained from hybridomas by the fusion of MRL/lpr/lpr splenocytes with murine myeloma cells. Some of these monoclonal anti-DNA antibodies showed cross reactivity with GAGs, such as hyaluronic acid, chondroitin sulfate and heparan sulfate. To elucidate the mechanism of cross reactivity, inhibition assays with propanol and polyethylenimine (PEI), a cationic agent, were carried out. Increase of the concentration of PEI (0.6-2.0% vol/vol) resulted in a dose dependent decrease in the binding ability of anti-DNA antibody to GAGs. Propanol, an organic reagent which disrupts the van der Waals bonds between epitopes and paratopes, showed little inhibitory effect on the binding activity of monoclonal anti-DNA antibody to GAGs. These results indicate that the binding of anti-DNA antibody to GAGs is due to a charge interaction rather than van der Waals forces. Anti-DNA antibody which can react with GAGs in the glomerular basement membrane seems to play an important role in the pathogenesis of lupus nephritis.

Animals↗

[A clinicopathological study of patients with immune complex type and pauci immune type rapidly progressive glomerulonephritis].

We made clinicopathological studies of twelve patients with rapidly progressive glomerulonephritis (RPGN) treated at our department of Okayama University Medical School Hospital for the last eight years. By immunofluorescence microscopy, seven cases were immune complex (IC) type and five were pauci immune type. By light microscopy, the mean percentage of glomeruli with crescents was seventy five, and cellular and fibro-cellular crescents were dominant in eleven cases. Combined therapy including methylprednisolone pulse or oral steroid was effective in eleven. Hemodialysis was performed in four patients with severe uremia and three of them recovered from hemodialysis. Two cases of RPGN associated with systemic lupus erythematosus died of cerebral hemorrhage. We conclude that IC type and pauci immune type RPGN have good prognosis when treated at their active stage with intensive combined therapy and with hemodialysis if necessary.

Adult↗

Selective decreased de novo synthesis of glomerular proteoglycans under the influence of reactive oxygen species.

The effect of reactive oxygen species on de novo synthesis of heparan sulfate proteoglycans (HSPGs) of the renal glomerulus was investigated in an organ perfusion system. Isolated kidneys were perfused for 7 hr with a medium containing [35S]sulfate to label sulfated proteoglycans or [35S]methionine to label total glomerular glycoproteins. For the generation of reactive oxygen species, xanthine and xanthine oxidase were included in the perfusion medium, and catalase and superoxide dismutase were used as scavenging agents. Proteoglycans were characterized by Sepharose CL-6B and DEAE-Sephacel chromatographies and SDS/PAGE analysis. The labeled glycoproteins were immunoprecipitated with anti-HSPG, anti-type IV collagen, and anti-laminin, and their specific radioactivities were determined. With exposure to reactive oxygen species, a drastic dose-dependent decrease in de novo synthesis of proteoglycans was seen, and that effect was reversible by catalase treatment. No alterations in the biochemical characteristics of proteoglycans were noted. Immunoprecipitation studies revealed a 16-fold decrease in the synthesis of nascent core peptide of HSPGs, while at comparable concentrations of xanthine and xanthine oxidase, synthesis of type IV collagen and laminin slightly decreased (approximately 15%). Morphologic studies revealed a 14-fold decrease in [35S]sulfate-associated autoradiographic grains overlying the glomerular basement membrane, a critical component of the ultrafiltration apparatus. Relevance of the selective decreased de novo synthesis of HSPGs of the glomerular basement membrane is discussed in terms of increased glomerular permeability to plasma proteins.

Animals↗

Modulation of glomerular proteoglycans by insulin-like growth factor-1.

Effect of insulin-like growth factor-1 (IGF) on the synthesis of glomerular proteoglycans (PGs) in an ex vivo recirculating organ perfusion system was investigated. Kidneys were perfused with a medium (approximately 80 ml) containing [35S]-sulfate (250 microCi/ml) and IGF (62.5 to 625 ng/ml). After radiolabeling, a small cortical piece was saved for tissue autoradiography, and the remaining kidney and the perfusion medium were utilized for biochemical studies. The glomeruli were isolated; their PGs extracted and characterized. A two- to threefold increase of the total radioactivities in tissue and media fractions was observed with the exposure to IGF. By Sepharose CL-6B chromatography, the tissue PGs eluted as two peaks (A and B) with Kav = 0.24 and 0.48, and the majority of the radioactivity was confined to peak A. This peak contained intact PGs while peak B included glycosaminoglycan (GAG) chains. Elution profiles of the glomerular PGs were similar in the control and IGF groups. However, there was a disproportionate increase of chondroitin/dermatan sulfate in the IGF group. The media fractions also had two peaks, and most of the radioactivity was associated with peak B containing GAG chains. A remarkable accentuation of peak B along with significant increase in the chondroitin/dermatan sulfate were observed in the IGF group. By DEAE-Sephacel chromatography, the PGs/GAGs of IGF group eluted at a relatively lower salt concentration as compared to the control. Autoradiography revealed a relatively high concentration of radioactivity over the mesangium as compared to the other cell types of the glomerulus. [35S]-methionine studies revealed a generalized increase of protein synthesis in the IGF group, but comparatively much less than that of PGs/GAGs. These results indicate that IGF enhances the biosynthesis of PGs/GAGs by various cell types of the renal glomerulus, especially that of the mesangial cell, as reflected by the selective increase of chondroitin/dermatan sulfate.

Animals↗

Interleukin-1-induced alterations in glomerular proteoglycans: biochemical and tissue autoradiographic aspects.

The effect of interleukin-1 alpha (IL-1) on the synthesis of glomerular basement membrane heparan sulfate-proteoglycan (HS-PG) was investigated. An ex vivo recirculating organ perfusion system was used. Kidneys were perfused with a medium containing (35S) sulfate and IL-1 (0.625 to 6.25 ng/mL). After radiolabeling was performed, a small cortical piece was saved for tissue autoradiography; the remaining kidney and perfusion medium were used for biochemical studies. Renal cortices were dissected out, and glomeruli were isolated; the PG were extracted and characterized. With exposure to IL-1 (5 ng/mL), an approximately twofold increase of the radioactivity in the glomerular fraction was noted. The increase was unaffected by indomethacin treatment. By Sepharose CL-6B chromatography, a single peak of radioactivity with Kav = 0.25 (macromolecular form of PG) was observed in the control group. The IL-treated group had two peaks of radioactivity with Kav = 0.25 and 0.45: the first peak contained PG, and the second peak consisted of free glycosaminoglycan (GAG) chains. Elution profiles of hydrolyzed tissue GAG chains were similar. No change in the ratio of chondroitin to heparan sulfate was observed. By DEAE-Sephacel chromatography, the glomerular PG/GAG of the IL-treated group eluted at a relatively lower salt concentration, suggesting a change in the charge density characteristics. No differences in the elution profiles of media PG/GAG were observed. (35S)methionine labeling of proteins showed no significant increase of the total radioincorporation in the IL-treated group. Immunoprecipitation studies revealed an approximately 88% increase in the de novo synthesis of PG. Tissue autoradiography revealed an approximately twofold increase of (35S) sulfate radioactivity over the glomerular mesangium, epithelium, and basement membranes. These results indicate that IL-1 enhances the synthesis of the macromolecular form of PG and the generation of free chains. Conceivably, such alterations may lead to defective macromolecular interactions among various components of the glomerular basement membrane and compromise the integrity of the ultrafiltration unit of the glomerulus.

Animals↗

[A case of giant prostatic calculi].

A 83-year-old man was admitted because of fever and painful swelling of the right scrotal contents on January 23, 1989. Kidney-ureter-bladder X-ray (KUB) showed multiple big prostatic calculi which were compressed postero-laterally by benign prostate hyperplasia (BPH) according to the CT film. UCG film revealed urethral stricture in the anterior urethra. He was diagnosed as having right epididymitis, urethral stricture, BPH and giant prostatic calculi. He was treated with right orchiectomy, urethral bougie and suprapubic prostatectomy with removal of the calculi. The total weight of the prostatic calculi was 28 g of consisted of 125 pieces. The postoperative course was uneventful and two years after the operation he has been well and free from evident disease.

Aged↗

[A case of retroperitoneal teratoma showing high level of CA19-9].

We report a case retroperitoneal mature teratoma showing an abnormally high CA19-9 (carbohydrate antigen 19-9) serum level in a 30-year-old woman. She was hospitalized for an episode of left upper abdominal pain. High CA19-9 tissue level and immunohistochemical findings were found in removed tissue. This case is the third report of a CA19-9-producing teratoma and literature was reviewed and discussed.

Adult↗

Nephritogenicity of anti-proteoglycan antibodies in experimental murine lupus nephritis.

BACKGROUND: Cross-reactivity between anti-DNA antibodies and heparan sulfate (HS)/heparan sulfate-proteoglycan (HS-PG) of glomerular basement membrane has been previously reported. Conceivably, this determines the final outcome of glomerular injury in lupus nephritis. EXPERIMENTAL DESIGN: We investigated the status of glomerular injury in NZB/NZW F1 mice after the administration of rabbit anti-HS-PG antibody (experiment group). The controls received normal rabbit IgG only. RESULTS: All experimental animals became proteinuric 2 weeks after the administration of anti-HS-PG. The animals of the older age group (16 weeks) had significant hematuria as well. Their glomeruli exhibited hypercellularity with a heavy influx of polymorphonuclear leukocytes and monocytes into their capillaries, and some of them exhibited crescentic changes. Electron-dense deposits were present in subepithelial, subendothelial, and mesangial regions of the glomeruli. The control group had normocellular glomeruli with a few mesangial deposits. Mouse IgG and C3 displayed a granular pattern of immunofluorescence in the experimental group. Anti-rabbit IgG titers in the serum were higher in the control group, which lower in the renal glomerular eluates. No significant differences were observed in the concentrations of anti-dsDNA and -ssDNA either in the sera or in the eluates. There was also no difference between the control and experimental group in terms of antibody synthesis by the splenic lymphocytes and their proliferation subsequent to antigenic challenge. CONCLUSIONS: Data suggest that administration of anti-HS-PG accentuates the glomerular injury during the natural course of lupus nephritis in (NZB/NZW F1 mice; seemingly these two antibodies (anti-HS-PG and -DNA) do not competitively inhibit the binding of the other to the same anionic sites of glomerular basement membrane enriched with heparan sulfate in vivo.

Animals↗