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Y Tomiyoshi

Publications and source records attributed to Y Tomiyoshi.

At least 19 recordsLinked to original sources
PubMed2001

Somatostatin analogue attenuates estrogen-induced augmentation of glomerular injury in spontaneous hypercholesterolemic female Imai rats.

BACKGROUND: Aggravating effect of estrogen replacement therapy on glomerular injury associated with an elevation of growth hormone (GH) levels has been reported. Therefore, in the present study, to clarify an association between GH elevation and the aggravating effect of estrogen on glomerular injury, we investigated the effect of somatostatin, an inhibitor of GH secretion, on glomerular injury in estrogen-treated hypercholesterolemic female Imai rats. METHOD: Control female rats were assigned to group 1 (Cont, n = 10). Group 2 (Cont-E, n = 10) received estrogen, and groups 3 (Cont-E-LS, n = 10) and 4 (Cont-E-HS) received estrogen and either a low dose of somatostatin analogue or a high dose of somatostatin analogue. Body weight, urinary protein, serum albumin, total cholesterol, triglycerides, blood urea nitrogen and serum creatinine were investigated every 4 weeks from 10 weeks through 30 weeks of age. At 30 weeks of age, rats were studied morphologically. RESULTS: Estrogen administration resulted in an increase in urinary protein excretion rates and serum total cholesterol levels, and aggravated glomerular injury associated with an increase in GH. In contrast, somatostatin treatment reduced both urinary protein excretion rates and total cholesterol levels and attenuated glomerular injury to levels close to those of controls associated with a reduction of GH levels. CONCLUSION: The results suggest that increased GH levels may contribute to an enhancing effect of estrogen administration on glomerular injury.

Animals↗
PubMed2001

Cellular crescents and segmental glomerular necrosis in IgA nephropathy are indicative of the beneficial effects of corticosteroid therapy.

OBJECTIVE: Recent reports have revealed that corticosteroid (PSL) therapy has a long-term beneficial effect for stabilization of renal function in progressive IgA nephropathy. PATIENTS AND METHODS: We analyzed serum creatinine (Cr), daily proteinuria and the results of other routine laboratory examinations during a short-term course of PSL therapy in 28 cases of progressive IgA nephropathy. The cases were divided into two groups according to changes in renal function during the PSL treatment period: group I (15 cases), improved renal function; group II (13 cases), no significant change in renal function. RESULTS: In group I, serum Cr and proteinuria were significantly decreased, with maximum effects observed at 3 months of PSL therapy, and remained low during the period of treatment. In contrast, group II showed no significant changes in serum Cr levels during the period of therapy, although proteinuria was transiently decreased after 3 months of therapy. Histologically, cellular/fibrocellular (C/F) crescents and/or segmental glomerular necrosis (SGN) occurred with a significantly higher incidence in group I (87%) than in group II (46%) (p < 0.05). CONCLUSIONS: These results suggested that the early response to PSL in reducing serum Cr and proteinuria by 3 months of treatment may be clinically useful to predict the prognosis of IgA nephropathy and that C/F crescents and/ or SGN may be histologically indicative of the beneficial effects of PSL therapy in IgA nephropathy.

Adult↗
PubMed2000

Combined therapy with estrogen and testosterone eliminates the aggravating effect of estrogen replacement therapy on glomerular injury in hypercholesterolemic female Imai rats.

Hypercholesterolemic Imai rats spontaneously develop proteinuria and glomerulosclerosis, especially male animals. Ovariectomy aggravates glomerular injury in female Imai rats. However, estrogen replacement therapy did not abolish this aggravating effect of ovariectomy and rather aggravated glomerular injury with an increase in serum levels of lipids and growth hormone (GH). Whereas we have already reported that treatment with testosterone in addition to estrogen reduces GH levels and attenuates glomerular injury as compared with estrogen alone in male Imai rats, in the present study, to investigate whether increased GH levels may contribute to an enhancing effect of estrogen on glomerular injury, we treated ovariectomized female Imai rats with estrogen pulse testosterone. Group 1 was sham operated and group 2 was ovariectomized at 6 weeks of age. Groups 3, 4, and 5 were ovariectomized and received estrogen, testosterone, or estrogen plus testosterone, respectively. Body weight, urinary protein, and serum constituents were investigated every 4 weeks from 12 to 24 weeks of age. At 24 weeks of age, the rats were studied morphologically. Each treatment with estrogen or testosterone equally aggravated glomerular injury with an increase in both proteinuria and serum lipids with increased serum GH levels in estrogen-treated rats but without influencing GH levels in testosterone-treated rats; combined treatment with estrogen plus testosterone resulted in a reduction of both proteinuria and serum lipids to levels of the controls and attenuated glomerular injury to levels close to those of controls with a reduction of the elevated serum GH levels. These results suggest that increased GH levels may contribute to an enhancing effect of estrogen replacement therapy on glomerular injury and that testosterone, when administered to the estrogen-treated rats, seems to exert an attenuating effect on glomerular injury by suppressing GH levels.

Animals↗
PubMed2000

Recurrence of rapidly progressive glomerulonephritis probably associated with two different kinds of drugs.

We describe a rare case that developed a rapidly progressive glomerulonephritis twice in a 69-year-old man during a course of treatment, first with allopurinol and then with piperacillin. The cessation of each treatment was followed by spontaneous recovery in renal function. A renal biopsy showed crescentic glomerulonephritis with mild tubulointerstitial change and a skin biopsy showed leukocytoclastic vasculitis. This is, to our knowledge, a very rare case of crescentic glomerulonephritis, probably associated with vasculitis during a course of treatment with two different kinds of drugs.

Aged↗
PubMed1999

Efficacy of blood purification therapy for heat stroke presenting rapid progress of multiple organ dysfunction syndrome: a comparison of five cases.

Five patients were admitted to our hospital because of classical heat stroke during the heat waves which attacked our country in the summers 1994 and 1995. The clinical and laboratory findings of all patients suggested the rapid progress of multiple organ dysfunction syndrome (MODS). Blood purification (BP) therapy, in addition to conventional treatment, was performed in three of the patients. Despite their disastrous general condition, all completely recovered or recovered sufficiently to be transferred to a rehabilitation hospital. Two additional patients were treated with conventional treatment only and both died in 1-3 days after admission. Clinical characteristics and laboratory findings on admission showed no differences between the cases receiving BP therapy and those not receiving BP therapy. These findings suggest that, in heat stroke patients, additional BP therapy may provide a better prognosis than conventional therapy only. These beneficial effects of BP may have been due mainly to the removal of proinflammatory cytokines related to heat stroke.

APACHE↗
PubMed1998

Retroperitoneal fibrosis with perinuclear antineutrophil cytoplasmic antibodies and a longitudinally extended periaortic soft-tissue structure on CT.

A 63-year-old woman showed positive perinuclear antineutrophil cytoplasmic antibodies (pANCA) and presented with an interesting CT finding of a periaortic soft-tissue structure seen as a rind of tissue surrounding the aorta, extending longitudinally from descending thoracic aorta to bilateral common iliac arteries which was compatible with an early stage of retroperitoneal fibrosis (RPF). Both pANCA titers and a periaortic mass volume were reduced following corticosteroid treatment. No cases of RPF with a periaortic mass associated with pANCA have been described. Our findings of RPF with pANCA positivity may enlarge the groups of ANCA-associated diseases.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed1998

Estrogen replacement therapy with its physiological dose does not eliminate the aggravating effect of ovariectomy on glomerular injury in hypercholesterolemic female Imai rats.

Hypercholesterolemic Imai rats spontaneously develop proteinuria and glomerulosclerosis, especially in males. Estrogen administration attenuated glomerular injury in male Imai rats, and the aggravating effect of ovariectomy in female rats is found. To clarify whether this aggravating effect of ovariectomy is due to a lack of estrogen, we administered estrogen to ovariectomized female Imai rats. At 6 weeks of age, group 1 (control) was sham-operated and group 2 was ovariectomized. Groups 3 and 4 were ovariectomized and received estrogen replacement therapy (0.1 mg in group 3 and 0.2 mg in group 4 once a month subcutaneously). Body weight, urinary protein and serum constituents were investigated every month from 3 to 6 months of age. At 6 months of age, rats were studied morphologically. Estrogen replacement therapy increased serum estrogen to levels close to those of controls when 0.1 mg was used, or higher when 0.2 mg was used. Estrogen replacement therapy with 0.1 mg did not eliminate the aggravating effect of ovariectomy on glomerular injury and rather aggravated it, but conversely therapy with 0.2 mg attenuated glomerular injury and abolished the aggravating effect of ovariectomy. Estrogen replacement therapy markedly elevated serum GH levels dose-dependently. These results suggested that other hormones as well as estrogen may play a protective role of the ovary for the development of glomerular injury, and that estrogen seems to exert a dual effect on glomerular injury.

Animals↗
PubMed1998

Fibrillar crystal structure in essential monoclonal IgM kappa cryoglobulinemia.

In monoclonal IgG cryoglobulinemia, two types of crystallization have been demonstrated with electron microscopy at high magnification. In contrast, little information is available on well-defined crystallization in cases of monoclonal IgM cryoglobulinemia. We present a case of pure monoclonal IgM kappa cryoglobulinemia and rapidly progressive glomerulonephritis occurring in a 75-year-old woman. We detected unequivocal formation of fibrillar crystal structure within intraglomerular macrophages on electron microscopy: the structure accords with that in a case of monoclonal IgG cyroglobulinemia described in the literature.

Aged↗
PubMed1997

The ovaries attenuate the aggravating effect of testosterone on glomerular injury in Adriamycin-induced nephropathy of female rats.

To clarify whether the ovaries have a potential to attenuate the aggravating effect of testosterone (T) on glomerular injury, we investigated the effect of T in female rats with or without ovaries, using Adriamycin (ADR)-induced nephropathy in female Sprague-Dawley rats. Group 1 consisted of female control rats, group 2 received T, groups 3 and 4 were subjected to ovariectomy (OVX) at 5 weeks of age, and group 4 received further T treatment. Group 5 consisted of male control rats. T was injected subcutaneously every 4 weeks from 5 weeks of age through the end of the experiment. ADR 2 mg/kg was administered intravenously to all rats twice, at 8 weeks of age and 20 days later. Body weight, blood pressure, urinary protein and serum constituents were investigated every 4 weeks from 4 through 24 weeks after the second ADR injection. Each group was studied morphologically 24 weeks after the second ADR injection. Treatment with T or with OVX and T significantly increased the urinary protein excretion. OVX had no significant effect on the urinary protein excretion. Treatment with either T or OVX did not induce any significant effects on the renal function with regard to blood urea nitrogen (BUN), serum creatinine (Cr) and Cr clearance (Ccr) levels, but a combined treatment with OVX and T significantly lowered the serum albumin levels, increased the levels of BUN and Cr and lowered the Ccr values. The glomerulosclerosis index was significantly and markedly higher in control male rats than in control females. Treatment with T resulted in a slight but significant increase in glomerular injury to levels similar to those seen in ovariectomized rats. Combined treatment with OVX and T significantly aggravated glomerular injury in a somewhat accelerated manner, associated with a significant increase in glomerular tuft volume. Our results suggested that the ovaries could not completely suppress glomerular injury worsened by T administered at serum levels similar to those of male rats, but they had a potential to attenuate glomerular injury induced by T, and the protective effect of the ovaries on glomerular injury may be related to their attenuating effect on glomerular growth.

Animals↗
PubMed1997

Testosterone does not eliminate the attenuating effect of estrogen on progressive glomerular injury in estrogen-treated hypercholesterolemic male Imai rats.

Hypercholesterolemic Imai rats spontaneously develop proteinuria and glomerulosclerosis, especially males. Estrogen attenuates the progressive glomerular injury in these male rats. To clarify whether this attenuating effect of estrogen depends on a reduction of testosterone and/or a reduction of the sex-related factors, we investigated whether testosterone administration eliminates the attenuating effect of estrogen on the development of glomerular injury in estrogen-treated male Imai rats. Estrogen significantly reduced sex-related low molecular weight protein excretion to undetectable levels; and treatment with estrogen and testosterone failed to increase these levels. Unexpectedly, treatment with estrogen and testosterone attenuated glomerular injury more than treatment with estrogen only. Estrogen significantly increased both levels of estrogen and growth hormone (GH), whereas it suppressed testosterone levels. Testosterone administration resulted in an increase in serum testosterone levels of about fivefold above the control levels, but reduced the elevated serum GH to the levels of the controls. These results suggest that estrogen appears to play a protective role by itself or in association with sex-related factors, independent of the levels of serum testosterone, and that testosterone does not exert its effect on augmenting glomerular injury and rather may act to attenuate glomerular injury associated with a reduction of GH levels.

Aging↗
PubMed1997

Different effect of estrogen administration from castration on glomerular injury in unilaterally nephrectomized male Sprague-Dawley rats.

We have already reported an equally attenuating effect of castration or estrogen administration on the development of focal segmental glomerulosclerosis (FSGS) in the animal models of a short-term experimental period ended at 24 weeks. In the present study, to clarify the importance of the experimental period in studying the pathogenesis of the development of FSGS, we investigated a long-term effect of castration or estrogen administration on FSGS using an experimental model of uninephrectomized Sprague-Dawley (SD) rats ended at 54 weeks. Thirty male SD rats received unilaterally right nephrectomy at 6 weeks of age. They were divided into three groups: group 1 was control; group 2 was castrated at 6 weeks, and group 3 was administered 0.2 mg estrogen subcutaneously once a month from 6 weeks of age. Body weight, urinary protein, serum albumin and other serum constituents were investigated every 12 weeks from 18 to 54 weeks of age. Each group was studied morphologically at the end of the experiment. Castration attenuated glomerular injury to the same extent as seen in the study of a short-term experimental period, while estrogen administration failed to attenuate glomerular injury, although each treatment equally suppressed an urinary excretion of a sex-related low-molecular-weight (LMW) protein. Castration reduced significantly kidney weight (KW), glomerular volume (GV) and serum growth hormone (GH) levels, but estrogen treatment failed to reduce KW and GV, and conversely elevated GH levels. These results suggest that a sex-related LMW protein influenced by castration or estrogen treatment may not play an important role in the development of FSGS and that an increase in plasma GH levels may contribute to the failure of an attenuating effect of estrogen on glomerular injury.

Animals↗
PubMed1997

Renal parenchymal malakoplakia in a four-week-old infant.

We describe a four-week-old male infant with bilateral renal parenchymal malakoplakia who presented with low grade fever, convulsions and lethargy. The patient had profound anemia, hepatosplenomegaly and bilateral nephromegaly with reduced renal function. Both blood and urine cultures grew Escherichia coli, and antibiotic therapy was started. A kidney biopsy obtained on the 20th hospital day confirmed the diagnosis of renal parenchymal malakoplakia. Following treatment with an intravenous methylprednisolone pulse therapy, the infant made significant clinical improvement. He has grown and developed normally in the three years following this episode. We suggest that the steroid therapy was useful in ameliorating renal parenchymal malakoplakia in a patient without an underlying systemic disease. This report describes the youngest patient to have malakoplakia.

Anti-Infective Agents, Urinary↗
PubMed1996

Sex difference in progression of adriamycin-induced nephropathy in rats.

To clarify the pathogenesis of focal-segmental glomerulosclerosis, we investigated the sex-related difference and the effect of castration in Adriamycin (ADR) induced nephropathy of Sprague-Dawley rats. At 5 weeks of age, group 1 female and group 2 male rats were sham operated, and group 3 male rats were castrated. ADR 2 mg/kg was intravenously administered to all rats at 8 weeks of age twice at a 20-day interval. Body weight, blood pressure, urinary protein, and serum constituents were investigated every 4 weeks, 4-20 weeks after the second ADR injection. Each group was studied morphologically 12 and 20 weeks after the second ADR injection. ADR induced massive proteinuria in male rats, whereas it induced significantly lower proteinuria in female rats, and castration significantly reduced proteinuria of male rats to an extent equal to the levels seen in female rats. Control male rats had significantly lower serum albumin levels and a significantly greater impairment of renal function (blood urea nitrogen and creatinine levels) than the female rats or the castrated male rats at 20 weeks. The glomerulosclerosis index was significantly higher in control male rats than in female rats, and castration attenuated glomerular injury of male rats to an extent close to the levels seen in female rats, though there was a significant difference in the glomerulosclerosis index between female rats and castrated male rats. The three groups did not differ in blood pressure and plasma somatomedin C and serum growth hormone levels, whereas the plasma testosterone levels were decreased to undetectable in female and castrated male rats, resulting in a reduction of sex-related low molecular weight protein in urine. These observations suggest that sex hormones such as testosterone and estrogen and/or sex-related low molecular weight protein regulated by testosterone and estrogen may play a contributory role in sex differences in the progression of glomerulosclerosis in ADR-treated rats.

Animals↗