[Effect of interferon therapy on hepatitis B virus related membranous nephropathy associated with focal segmental glomerulosclerosis]

We experienced a 24-year-old Japanese man, who was a hepatitis B virus carrier with nephrotic syndrome. Liver biopsy showed that he was suffering from chronic hepatitis (activity 2, fibrosis 2). Renal biopsy revealed membranous nephropathy(MN) with focal segmental glomerulosclerosis(FGS). Immunofluorescentic findings revealed the presence of HBe antigen along the glomerular capillaries as well as HBe antigenemia in circulation. Therefore, we diagnosed this case as HB virus-related membranous nephropathy associated with FGS lesions. He was treated with interferon(IFN) alpha-2b for over a month and angiotensin converting enzyme inhibitor. These therapies reduced urinary protein excretion from 4-6 g/day to 1-2 g/day, in accordance with a decrease in the titer of HBV DNA polymerase. The second renal biopsy revealed that the histological change from MN to membranoproliferative glomerulonephritis Type III after IFN therapy. These results suggest that IFN therapy might be effective for HB virus-related MN associated with FGS.

Multi-level Disruption of the Spinal Nerve Root Sleeves in Spontaneous Spinal Cerebrospinal Fluid Leakage. Two Case Reports

A 37-year-old male and an 18-year-old male presented with spontaneous spinal cerebrospinal fluid (CSF) leakage from multiple nerve root sleeves. Both patients suffered abrupt onset of intense headache followed by nausea, dizziness, and one patient with and one without positional headache. Radioisotope spinal cisternography of both patients revealed that the CSF leaks were not localized in a special zone but distributed to multiple spinal nerve root sleeves. Magnetic resonance (MR) myelography suggested that the spinal CSF column was fully expanded to the root sleeves. The extraspinal nerve bundles demonstrated numerous high intensity spots. Both patients were treated conservatively, and their symptoms resolved within one month. Repeat radioisotope cisternography and MR myelography confirmed the spine was normal after recovery. We suggest that spreading disruption of the arachnoid membrane occurs at the nerve root sleeves due to CSF overflow into the spinal canal.

Diabetes and tumor formation in transgenic mice expressing Reg I

To examine the effect of overexpressed regenerating gene (Reg) I on pancreatic beta-cells, we generated transgenic mice expressing Reg I in islets (Reg-Tg mice). Three lines of Reg-Tg mice were established. In line-1 Reg-Tg mice, the expression level of Reg I mRNA in islets was 7 times higher than those in lines 2 and 3 of Reg-Tg mice, and line 1 mice developed diabetes by apoptosis of beta-cells, as well as various malignant tumors. In addition to the decrease in beta-cells, compensatory islet regeneration and proliferation of ductal epithelial cells were observed in line-1 Reg-Tg mice. Because Reg I protein was secreted primarily into pancreatic ducts from acinar cells, it may primarily stimulate the proliferation of ductal epithelial cells, and not beta-cells, and their differentiation into islets. Moreover, the tumor-promoting activity of Reg I protein should be considered for its possible clinical applications.

Primary choroid plexus carcinoma producing carbohydrate antigen 19-9

An autopsy case of primary choroid plexus adenocarcinoma arising in a 40-year-old female, who was associated with a high serum level of a carbohydrate antigen 19-9 (CA19-9), is herein presented. After a subtotal removal of a tumor in the left lateral ventricle, the serum level of CA19-9 decreased rapidly, and immunohistochemical examinations of tumor tissue specimens obtained at surgery revealed intense reactivity for CA19-9. The present case may be the first example in which a primary choroid plexus carcinoma was shown to produce CA19-9.

Up-regulation of monocyte chemoattractant protein-1 in tubulointerstitial lesions of human diabetic nephropathy

BACKGROUND

We previously described that monocyte chemoattractant protein-1 (MCP-1) plays an important role in progressive glomerular and interstitial damage in inflammatory renal diseases. However, the expression of MCP-1 in diabetic nephropathy remains to be investigated.

METHODS

We examined whether locally expressed MCP-1 participates in human diabetic nephropathy via recruiting and activating monocytes/macrophages (Mphi). Urinary and serum MCP-1 levels were measured by enzyme-linked immunosorbent assay in 45 patients with diabetic nephropathy. The presence of MCP-1 in diseased kidneys was determined by immunohistochemical and in situ hybridization analyses.

RESULTS

Urinary MCP-1 levels were significantly elevated in patients with diabetic nephrotic syndrome and advanced tubulointerstitial lesions. Moreover, urinary levels of MCP-1 were well correlated with the number of CD68-positive infiltrating cells in the interstitium. In contrast, serum MCP-1 levels remained similar to those of healthy volunteers. Furthermore, we detected the MCP-1-positive cells in the interstitium of diabetic nephropathy via both immunohistochemical and in situ hybridization analyses.

CONCLUSION

These observations suggest that locally produced MCP-1 may be involved in the development of advanced diabetic nephropathy, especially in the formation of tubulointerstitial lesions possibly through Mphi recruitment and activation. Moreover, up-regulation of MCP-1 may be a common pathway involved in the progressive tubulointerstitial damage in diabetic nephropathy as well as inflammatory renal diseases.

Alcohol enhances characteristic releases of dopamine and serotonin in the central nucleus of the amygdala

The amygdaloid complex (AMY) is implicated in emotional and motivational aspects of behavior, including the formation of positive reinforcement association. AMY may also associated with brain rewarding circuitry. In the present study, the effect of ethanol (EtOH) on the release of dopamine (DA) and serotonin (5-HT) was studied in the central amygdaloid nucleus (CeAMY), and projecting excitatory afferents to the ventral tegmental area (VTA), of freely moving Wistar rats by brain microdialysis. Within 20 min of i.p. injection of EtOH (2 g/kg), the levels of DA and 5-HT in the CeAMY dialysate increased over the baseline value by 270 and 160% (N = 6-7), respectively. Addition of EtOH (25, 50 and 100 mM) to the microdialysis perfusion medium for 1 h caused a 115-150% dose-related increase in the extracellular level of DA in the CeAMY. 100 mM EtOH-induced CeAMY DA release continued to increase for 1 h after the perfusion medium was returned to normal perfusion medium. In contrast, the CeAMY 5-HT level was increased only by the addition of 100 mM EtOH for 1 h to 130% for 80 min. The stimulation of the CeAMY by EtOH through the microdialysis membrane showed delayed responses of DA and 5-HT compared with the i.p. injection of EtOH. Overall, the present findings are not sufficient to conclude whether EtOH acts directly or indirectly on the major monoamine nerve cells in the CeAMY, but the degree of acute EtOH action affected the differences in time at the peak response on EtOH-induced DA and 5-HT releases in the CeAMY via VTA.

[A case of high-age minimal change nephrotic syndrome relapse after 18-year remission and effective treatment with steroid and cyclosporin combined therapy]

We describe the clinical course of a 69-year-old woman, who suffered from minimal change nephrotic syndrome(MCNS) after long-term remission. In 1979, she was admitted to Kanazawa University Hospital due to MCNS verified by renal biopsy and was treated with oral prednisolone(initially 40 mg/day) for two years. She suffered from edema again in 1999 with massive proteinuria. Renal biopsy revealed minor glomerular abnormality without any deposition of immunoglobulins or complements. Electron microscopic findings showed extensive foot process effacement. Therefore, we diagnosed this case as a recurrence of MCNS. She was treated with the combination of methylprednisolone pulse therapy(500 mg, 3 days), oral prednisolone(20 mg/day) and cyclosporin(CyA, 3 mg/kg/day), which could induce earlier complete remission. These results suggest that recurrence after long-term remission could occur in adult-onset MCNS and that the combination therapy of prednisolone and CyA may be effective for the induction of early remission in MCNS.

Multiple endocrine neoplasia type 1: from bedside to benchside

Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant disorder characterized by the combined occurrence of parathyroid, pancreatic endocrine, and anterior pituitary tumors. MEN1 has two characteristics; a hormone excess and a sometimes lethal outcome due to malignant tumors. The recent identification of the MEN1 gene has opened the door to a much deeper understanding of this syndrome. Germline MEN1 mutations have been identified in most MEN1 families. They were not found, however, in families with familial pituitary tumors. Thus, studies with the MEN1 gene helped to establish that mutation of some other gene(s) is likely causative of the MEN1 phenocopy. These recent advances provide for the identification of mutant MEN1 gene carriers who are at a high risk of developing MEN1. The protein encoded by the MEN1 gene has been shown to function in the regulation of JunD-activated transcription but much still remains to be elucidated.

The zitter mutant rat exhibits loss of D3 receptors with degeneration of the dopamine system

Experimental studies of the regulation of the dopamine (DA) D3 receptor have utilized techniques causing massive depletions of the DA system. Zitter mutant rats exhibiting a heterogeneous loss of striatal DA innervation were examined for DA transporter (DAT) binding and DA D3 receptor number by autoradiography and compared with Sprague-Dawley rats. A significant loss of DAT binding was observed with the greatest in the lateral caudate-putamen (72% loss) and the least in the nucleus accumbens (45% loss). DA D3 receptors were reduced by > 70% in all regions, even in the nucleus accumbens that exhibited considerably smaller depletions of DAT binding, indicating that loss of D3 receptors may occur prior to massive loss of DA innervation.

The rate of cell growth is regulated by purine biosynthesis via ATP production and G(1) to S phase transition

We recently showed that an increased supply of purine nucleotides increased the growth rate of cultured fibroblasts. To understand the mechanism of the growth rate regulation, CHO K1 (a wild type of Chinese hamster ovary fibroblast cell line) and CHO ade (-)A (a cell line deficient in amidophosphoribosyltransferase, a rate-limiting enzyme of the de novo pathway) were cultured under various conditions. Moreover, a defective de novo pathway in CHO ade (-)A cells was exogenously restored by 5-amino-4-imidazole-carboxamide riboside, a precursor of the de novo pathway. The following parameters were determined: the growth rate of CHO fibroblasts, the metabolic rate of the de novo pathway, the enzyme activities of amidophosphoribosyltransferase and hypoxanthine phosphoribosyltransferase, the content of intracellular nucleotides, and the duration of each cell-cycle phase. We concluded the following: (i) Purine de novo synthesis, rather than purine salvage synthesis or pyrimidine synthesis, limits the growth rate. (ii) Purine nucleotides are synthesized preferentially by the salvage pathway as long as hypoxanthine is available for energy conservation. (iii) The GTP content depends on the intracellular ATP content. (iv) Biosynthesis of purine nucleotides increases the growth rate mainly through ATP production and promotion of the G(1)/S transition.

Distinct expression of CCR1 and CCR5 in glomerular and interstitial lesions of human glomerular diseases

We investigated the presence of CCR1- and CCR5-positive cells immunohistochemically in the kidneys of 38 patients with several renal diseases, including 13 crescentic glomerulonephritis patients. In addition, we determined cell phenotypes of CCR1- and CCR5-positive cells using a dual immunostaining technique. Urinary levels of their ligands, for CCR1 and CCR5; macrophage inflammatory protein (MIP)-1alpha, MIP-1beta and regulated upon activation in normal T cells expressed and secreted (RANTES) were evaluated by enzyme-linked immunosorbent assay. CCR1- and CCR5-positive cells were detected in both glomeruli and interstitium of the diseased kidneys. Using a dual immunostaining technique, these positive cells were CD68-positive macrophages (MPhi) and CD3-positive T cells. The number of CCR1-positive cells in glomeruli was correlated with urinary levels of MIP-1alpha. The number of CCR1-positive cells in the interstitium was correlated with both urinary MIP-1alpha and RANTES levels. CCR1-positive cells in the interstitium remained after glucocorticoid therapy, most of which were MPhi, and were correlated with the intensity of interstitial fibrosis and tubular atrophy. Glomerular CCR5-positive cells were well correlated with extracapillary lesions and urinary MIP-1alpha levels, while interstitial CCR5-positive cells, mainly CD3-positive T cells, were correlated with interstitial lesions and urinary RANTES levels. Renal CCR5-positive cells were dramatically decreased during convalescence induced by glucocorticoids. These results suggest that chemokine receptor signaling may be pivotal for human renal diseases through the recruitment and activation of MPhi and T cells; CCR5-positive cells may participate in glomerular lesions including extracapillary lesions via MIP-1alpha and in interstitial lesions via RANTES. CCR1 may be involved in interstitial lesions in resolving phase after glucocorticoid therapy.

Involvement of tyrosine phosphorylation in the positive inotropic effect produced by H(1)-receptors with histamine in guinea-pig left atrium

We investigated the effect of stimulation of H(1)-receptors with histamine on protein tyrosine phosphorylation levels in guinea-pig left atrium and evaluated the influences of tyrosine kinase inhibitors on the positive inotropic effect mediated by H(1)-receptors in this tissue. Histamine induced an increase in tyrosine phosphorylation in four main clusters of proteins with apparent molecular weights of 25, 35, 65 and 150 kDa. Tyrosine phosphorylation of these proteins attained a peak around 2 - 3 min following histamine stimulation and then declined to or below basal levels. Histamine-induced protein tyrosine phosphorylation was antagonized by the H(1)-receptor antagonists mepyramine (1 microM) and chlorpheniramine (1 microM), but not by the H(2)-receptor antagonist cimetidine (10 microM). The positive inotropic effect of histamine was depressed in a concentration-dependent manner by the tyrosine kinase inhibitors tyrphostin A25 (50 to 100 microM) and genistein (10 to 50 microM) but not by the inactive genistein analogue daidzein (50 microM). The positive inotropic effect of isoprenaline was unchanged by tyrphostin A25 and genistein. At a concentration of 1 microM histamine produced a dual-component positive inotropic response composed of an initial increasing phase and a second and late developing, greater positive inotropic phase. Treatment with tyrphostin A25 (100 microM) and genistein (50 microM), but not daidzein (50 microM), significantly attenuated the two components of the inotropic response, although genistein suppressed the initial component more markedly than the late component. We conclude that increased protein tyrosine phosphorylation may play an important role in initiating at least some part of the positive inotropic effect of H(1)-receptor stimulation in guinea-pig left atrium.

Developmental changes in cerebrospinal fluid concentrations of monoamine-related substances revealed with a Coulochem electrode array system

The relationship between age and cerebrospinal fluid concentrations of monoamine-related substances, including kynurenine, were investigated using a Coulochem electrode array system, to clarify developmental changes in monoamine-related substances in the human central nervous system. In neurologically normal children, significant inverse correlations with age were observed for the cerebrospinal fluid concentrations of 5-hydroxytryptophan, 5-hydroxyindole-acetic acid, kynurenine, homovanillic acid, 3-methoxy-4-hydroxyphenyl glycol, and 3-O-methyl-dopamine. The concentrations of their precursors, tryptophan and tyrosine, were not related to age. This is the first comprehensive study revealing developmental changes in monoamine-related substances including their precursors and metabolites.

Molecular cloning and expression analysis of a putative nuclear protein, SR-25

We cloned a full-length mouse cDNA and its human homologue encoding a novel protein designated as "SR-25." In Northern blot analysis, SR-25 mRNA was expressed in all organs tested, and relatively abundant in testis and thymus. Deduced amino acid sequences of mouse SR-25 and human SR-25 showed 77.7% identity. SR-25 has a serine-arginine repeat (SR repeat) and two types of amino acid clusters: a serine cluster and a highly basic cluster. Based on the presence of many nuclear localizing signals and a similarity to RNA splicing proteins, SR-25 is strongly suggested to be a nuclear protein and may contribute to RNA splicing.

Age-related dopamine deficiency in the mesostriatal dopamine system of zitter mutant rats: regional fiber vulnerability in the striatum and the olfactory tubercle

Oxidant stress has been implicated in the pathogenesis of Parkinson's disease. To test the oxidant stress hypothesis of dopaminergic degeneration, age-related changes in the mesostriatal dopamine neuron system were compared between zitter mutant rats which have abnormal metabolism of oxygen species in the brain and Sprague-Dawley rat as a control using the neurochemistry and immunohistochemistry. Dopamine content in the caudate-putamen, nucleus accumbens and olfactory tubercle of zitter rats decreased significantly with age, and was lower than that found in corresponding age-matched controls. In the zitter rats, the reduction of dopamine was more prominent in the caudate-putamen than in the nucleus accumbens and olfactory tubercle. A characteristic decline of tyrosine hydroxylase-immunoreactive fibers in the caudate-putamen of the zitter rat was also observed. In the dorsolateral caudate-putamen, reduction of tyrosine hydroxylase-immunoreactive fibers was observed in the matrix-like area, whereas in the ventromedial caudate-putamen the reduction occurred in the patch-like areas. Degeneration of tyrosine hydroxylase-immunoreactive fibers which was characterized by swollen varicosities and clustered fibers was observed in the caudate-putamen and nucleus accumbens and preceded loss of normal tyrosine hydroxylase-immunoreactive fibers in the caudate-putamen. Thus, the depletion of dopamine in the terminal areas is related to axonal degeneration. However, there was no degenerative tyrosine hydroxylase-immunoreactive fibers in the olfactory tubercle at any examined age, but reductions of tyrosine hydroxylase-immunoreactive fibers and dopamine contents were noted in the olfactory tubercle after four months-of-age. Since the zitter rats have an abnormal oxygen metabolism, the degeneration of tyrosine hydroxylase-immunoreactive fibers could result from an accumulation of superoxide species. The present results provide support for the oxidant stress hypothesis of dopaminergic neuronal degeneration and further indicate the region-specific vulnerability of the nigrostriatal dopamine system.

Diabetes and pancreatic tumours in transgenic mice expressing Pa x 6

AIMS/HYPOTHESIS

Both endocrine and exocrine cells of the pancreas differentiate from epithelial cells of primitive pancreatic ducts, and four types of pancreatic islet cells (alpha, beta, delta, and PP cells) are derived from the common pluripotent precursor cells. Although Pa x 6 is expressed in all islet cells, Pa x 4 is detected only in beta cells. In homozygous Pa x 4-null mice, beta cells are absent, whereas the number of alpha cells is increased. Therefore, we hypothesized that the balance of Pa x 4 and 6 is one of the determinants by which the common progenitor cells differentiate into alpha or beta cells.

METHODS

To change this balance, we generated transgenic mice overexpressing Pa x 6 driven by the insulin promoter or the PDX1 promoter.

RESULTS

In both types of transgenic mice, normal development of beta cells was disturbed, resulting in apoptosis of beta cells and diabetes. In Insulin/Pa x 6-Tg mice, beta cells were specifically affected, whereas in PDX/Pa x 6-Tg mice, developmental abnormalities involved the whole pancreas including hypoplasia of the exocrine pancreas. Furthermore, PDX/Pa x 6-Tg mice experienced proliferation of both ductal epithelia and islet cells and subsequent cystic adenoma of the pancreas.

CONCLUSION/INTERPRETATION

These findings suggest that Pa x 6 promotes the growth of ductal epithelia and endocrine progenitor cells and that the suppression of Pa x 6 is necessary for the normal development of beta cells and the exocrine pancreas.

Changes in dopamine transporter and c-Fos expression in the nucleus accumbens of alcohol-tolerant rats

BACKGROUND

We have shown that neurochemical functions of 5-HT3 receptors in regulating dopamine (DA) release in the nucleus accumbens (ACC) after alcohol exposure compensate for the dysfunction of serotonergic activity to restore the original properties in processing alcohol tolerance, and that the development of alcohol dependence may be mediated by ACC 5-HT3 receptors. In the present study, the effects of chronic alcohol consumption on the functions of the dopamine transporter (DAT) and the expression of c-Fos proteins were investigated using in vivo brain microdialysis and immunocytochemistry.

METHODS

Perfusion of cocaine and 1-(2-Bis-(4-fluorophenyl) methoxy) ethyl)-4-(3-phenylpropyl) piperizine (GBR 12909) through the microdialysis probe membrane increased the extracellular levels of DA in ACC of alcohol-treated rats that had developed alcohol tolerance by drinking 10% EtOH for 30 days.

RESULTS

The magnitudes of DA reuptake or DAT inhibitors, cocaine, and GBR 12909 that induced DA availability in the ACC were significantly higher in alcohol-treated rats than in controls. When compared with control rats, the alcohol-treated rats exhibited higher levels of DA and its metabolite, DOPAC, in the ACC. Increased expression of the c-Fos-like protein was found in the ACC of alcohol-treated rats. These results show that (1) chronic alcohol consumption desensitizes or decreases the DAT of DA terminals in the ACC and that (2) EtOH causes cellular hyperexcitability of ACC dopaminergic neurons with increased Fos expression during alcohol tolerance.

CONCLUSION

The findings suggested that an abnormality of the dopaminergic neurons in the ACC that are involved with DAT dysfunction is associated with the development of alcohol tolerance.

Molecular cloning and tissue-specific expression of a new member of the regenerating protein family, islet neogenesis-associated protein-related protein

Islet neogenesis-associated protein (INGAP) is a protein expressed during islet neogenesis. We have cloned a novel cDNA having a similar sequence to INGAP cDNA. The cDNA encodes 175 amino acids designated INGAP-related protein (INGAPrP). INGAP is expressed in cellophane-wrapped pancreas, but not in normal pancreas, whereas INGAPrP was abundantly expressed in normal pancreas.

Relation of lifestyle factors to metacarpal bone mineral density was different depending on menstrual condition and years since menopause in Japanese women

OBJECTIVE

To examine whether the relation between lifestyle and metacarpal bone mineral density (BMD) varied with life-stages.

DESIGN

Cross-sectional study.

SETTING

Taking questionnaires related to lifestyle and examining metacarpal BMD by computed X-ray densitometry at a local health care center.

SUBJECTS

Out of 750 Japanese women aged 40-69 y old who underwent screening for osteoporosis, we selected 535 healthy subjects without medical conditions or lifestyle factors known to affect bone metabolism.

RESULTS

A cross-sectional comparison of BMD and years since menopause (YSM) resulted in a logarithmic regression model (BMD=2. 539-0.149xloge YSM, r2=0.418), indicating that a prominent reduction in metacarpal BMD appears up to 4-6 y after menopause. In premenopausal women with regular menstruation, those who engaged in regular physical activity during adolescence showed significantly greater BMD than those who did not. In 1-5-y postmenopausal women, those with current calcium intake of more than 800 mg/d, current milk intake greater than 900 ml/week, daily consumption of milk and/or dairy products, or frequent consumption of small fish showed significantly greater BMD. In 6-15-y postmenopausal women, those who took more than 6000 or 8000 steps/day showed significantly greater BMD.

CONCLUSIONS

The relation between lifestyle and BMD differed with life-stages in Japanese women. It was suggested that to perform lifestyle modifications for the prevention of osteoporosis, life-stages should be taken into consideration.

SPONSORSHIP

Grant for Research on Health Service from Ministry of Health and Welfare, Japan and grant from The National Dairy Promotion and Research Association of Japan. European Journal of Clinical Nutrition (2000) 54, 9-13

TRH increases cerebrospinal fluid concentration of kynurenine

We have analyzed changes in cerebrospinal fluid (CSF) concentrations of monoamine-related substances to clarify the mechanism of the antiepileptic action of thyrotropin-releasing hormone (TRH). TRH-tartrate was administered to 14 patients with intractable epilepsy. Before and 2 weeks after TRH administration, CSF was collected and analyzed for tryptophan and tyrosine metabolites. Among monoamine-related substances, only CSF concentrations of kynurenine were increased after TRH therapy. Considering the fact that kynurenic acid acts as antagonist on the NMDA receptor complex, the results of this study may explain at least one of the mechanisms of the effectiveness of TRH therapy for intractable epilepsy.