The nucleotide sequence of apple stem grooving capillovirus genome

The complete nucleotide sequence of apple stem grooving virus (ASGV) genome has been determined. The genome is 6496 nucleotides in length excluding a 3'-terminal poly(A) tail and contains two overlapping open reading frames (ORFs). ORF1 begins at nucleotide position 37 and is terminated at position 6341, encoding a protein with a molecular weight of 241 kDa. ORF2, which is in a different reading frame within ORF1, begins at position 4788 and can encode a 36-kDa protein. The 241-kDa protein contains two consensus sequences associated with the RNA-dependent RNA polymerase and the NTP-binding helicase. Comparisons of amino acid sequences around these conserved motifs with other RNA viruses revealed that ASGV has extensive similarities with apple chlorotic leaf spot, tymo-, carla-, and potexviruses, and is a member of the sindbis-like supergroup. ASGV coat protein is found to be located in the C-terminal region of the 241-kDa polyprotein. The 36-kDa protein encoded by ORF2 contains the consensus sequence Gly-Asp-Ser-Gly found in the active site of several cellular and viral serine proteases.

3,3',5'-Triiodothyronine inhibits collagen-induced human platelet aggregation

To clarify further the activity of rT3, we examined the effect of rT3 on collagen-induced platelet activation as reflected by aggregation, serotonin release, and protein phosphorylation. rT3, T4, T3, and triiodothyroacetic acid inhibited collagen-induced platelet aggregation and serotonin release from platelets in a dose-dependent manner. However, thyronine did not inhibit collagen-induced platelet aggregation. The concentration at which rT3 inhibited by 50% collagen-induced platelet aggregation was 30 +/- 4 (mean +/- SE) mumol/L. rT3, T4, and T3 did not differ significantly in their abilities to inhibit platelet aggregation. Moreover, rT3 inhibited collagen-induced phosphorylation of the 20-kilodalton protein (myosin light chain) in platelets. In contrast, rT3 did not inhibit 12-O-tetradecanoylphorbol 13-acetate (TPA)- or thrombin-induced platelet aggregation and inhibited only minimally TPA-induced 40-kilodalton protein phosphorylation. These results suggest that rT3 inhibits collagen-induced platelet activation by inhibiting the activity of myosin light chain kinase and that it may be interesting to investigate some kinds of activity of rT3.

Evidence for translation of apple stem grooving capillovirus genomic RNA

Apple stem grooving virus (ASGV) RNA was translated in a rabbit reticulocyte lysate system and shown to direct the synthesis of several polypeptides of Mr ranging from 200K to 43K. A polypeptide of 200K was a major product, but no polypeptide with electrophoretic mobility the same as that of the ASGV coat protein was synthesized. Immunoprecipitation experiments showed that a polypeptide of 200K was selectively precipitated by antiserum against purified ASGV. These results indicate that ASGV coat protein is translated as part of a 200K polyprotein.

Cyclosporin reduces proteinuria in rats with aminonucleoside nephrosis

The effect of cyclosporin (CS) was assessed in Sprague-Dawley rats with puromycin aminonucleoside (PA) nephrosis induced by a single intraperitoneal injection of PA. Three groups of rats were injected intraperitoneally with CS (10 mg/kg body weight) daily, beginning 1 day before PA administration, or 5 or 10 days after PA administration, for 10 days. CS significantly reduced proteinuria in rats with PA nephrosis in comparison with untreated nephrotic controls. After discontinuation of the CS treatment, proteinuria gradually increased, reaching values similar to those in control nephrotic rats. CS pretreatment did not prevent the induction of PA-induced nephrotic syndrome. Light microscopy and assessment of anionic sites in the glomerular basement membrane revealed no differences between normal rats, nephrotic controls, and CS-treated rats. These results show that CS can reduce proteinuria in PA nephrosis, but cannot ameliorate the glomerular changes.

Infusion of peripheral blood mononuclear cell products from nephrotic children increases albuminuria in rats

Supernatants of peripheral blood mononuclear cell culture from children with minimal change nephrotic syndrome (MCNS) and focal segmental glomerulosclerosis (FSGS) were tested for their ability to increase glomerular basement membrane (GBM) permeability and for effects on anionic sites in the GBM. Supernatants from cultures of concanavalin A-stimulated peripheral blood mononuclear cells from patients with MCNS, those with FSGS and normal controls were infused into the renal arteries of normal rats. Infusion of the supernatants from patients with MCNS and FSGS caused a significant reduction of anionic sites in the GBM (p less than 0.001) and a significant increase in urinary albumin excretion (p less than 0.05), whereas infusion of supernatants in control cases did not reduce anionic sites nor increase urinary albumin excretion. These findings show that stimulation of peripheral blood mononuclear cells from MCNS and FSGS with concanavalin A results in liberation of soluble substances which reduce polyanions in the GBM and increases GBM permeability.

Prognostic indicators in childhood IgA nephropathy

A number of clinical, laboratory and pathologic parameters were assessed for their prognostic significance in 200 children aged less than 15 years with IgA nephropathy, who had shown normal renal function at the time of initial biopsy and were followed for more than 2 years thereafter. After a mean follow-up period of 5.0 years from the initial biopsy, 93 patients had no demonstrable abnormality, 76 had minor urinary abnormalities, 21 had persistent heavy proteinuria and 10 had developed chronic renal impairment. A poor outcome was found to be correlated with heavy proteinuria at biopsy, diffuse mesangial proliferation, a high proportion of glomeruli showing sclerosis, crescents or capsular adhesions, the presence of moderate or severe tubulointerstitial changes, and the presence of subepithelial electron-dense deposits and lysis of the glomerular basement membrane by electron microscopy. The percentage of glomeruli displaying crescents, sclerosis and adhesions appeared to be the most reliable prognostic indicator. Nine of the 27 patients (33%) in whom greater than or equal to 30% of glomeruli showed crescents, sclerosis and adhesions developed chronic renal impairment, and only 14% of these patients had normal urine at follow-up. In contrast, only 1 of the 173 patients in whom less than 30% of glomeruli showed such lesions developed chronic renal impairment (p less than 0.001) and 51% of these patients showed complete remission at follow-up (p less than 0.001). These results demonstrate that an accurate prediction of the outcome based on the initial renal biopsy findings is possible early in the course of children with IgA nephropathy.

Human chorionic gonadotropin induces c-myc mRNA expression via TSH receptor in FRTL-5 rat thyroid cells

To elucidate the gene regulation of the thyroid-cell growth-promoting activity by human chorionic gonadotropin (hCG), we investigated the effect of hCG on c-myc proto-oncogene expression in cultured rat FRTL-5 cells by the Northern blot method. hCG induced c-myc mRNA expression, which peaked at 60-120 min. A dose-dependent increase in c-myc mRNA levels was also ascertained. In the presence of crude immunoglobulin G (IgG) from 2 patients with primary hypothyroidism who had blocking type TSH-receptor antibody, c-myc mRNA expressions induced by hCG were decreased to 82% and 62%, compared with that in the presence of normal IgG. The present results suggest that the expression of c-myc mRNA is a part of the molecular mechanism through which hCG regulates the proliferation of thyroid cells, and that hCG-induced c-myc mRNA expression is presumed to be mediated in part by TSH receptors.

Asymptomatic constant isolated proteinuria in children

The clinical features, renal biopsy findings, and subsequent course in 53 children with asymptomatic constant isolated proteinuria were studied retrospectively (1) to determine the prevalence of renal pathologic abnormalities among these children, (2) to identify those clinical characteristics that may enable recognition of children with an increased likelihood of having renal pathologic abnormalities, and (3) to assess the clinical course. All biopsy specimens were examined by light, immunofluorescence, and electron microscopy. Twenty-five patients (47%) had significant glomerular changes (15 had focal segmental glomerulosclerosis, 4 IgA nephropathy, 3 diffuse mesangial proliferative glomerulonephritis without IgA deposition, and 3 membranous glomerulonephritis), and 28 had minimal glomerular changes. There were no differences between the patients with significant glomerular changes and those with minimal glomerular changes with regard to clinical and laboratory findings except for a predominance of boys in the former group. At the latest follow-up, seven patients with significant glomerular changes, but none with minimal glomerular changes, had chronic renal impairment. Because of the high incidence of significant glomerular changes and the high rate of progression to chronic renal impairment, we believe that a renal biopsy is indicated for a child with asymptomatic constant isolated proteinuria.

Malignant amelanotic melanoma of the esophagus

The clinical, histological, and electron microscopic features of a case of malignant amelanotic melanoma of the esophagus are described. Amelanotic melanoma is difficult to distinguish from other malignant lesions, but in our case electron microscopy was helpful in the diagnosis.

Mechanism of thyroid stimulation by human chorionic gonadotropin in sera of normal pregnant women

To elucidate the mechanism of thyrotropic activity of human chorionic gonadotropin in sera of normal pregnant women, we examined the effect of blockade of the TSH receptor on the serum-induced cAMP accumulation and the effect of hCG on the TSH binding to FRTL-5 cells. In the presence of crude immunoglobulin fractions in sera from patients with primary hypothyroidism, cAMP accumulation induced by both crude and purified hCG, and normal pregnant women serum were significantly inhibited compared with that in the presence of normal IgGs. The mode of inhibition of these IgGs on the cAMP accumulation was similar for TSH and hCG when analysed by Lineweaver-Burk plots. Moreover, binding of [125I]bTSH to the TSH receptor in porcine thyroid cell membrane was apparently inhibited by adding 4 x 10(6) IU/l of purified hCG. Binding studies of TSH in FRTL-5 cells also indicated the dose-dependent displacements of [125I]TSH by hCG. Although half-maximal inhibitory concentration of hCG was about 20 times as high as that of TSH on a molar basis, displacement of [125I]TSH was observed at a concentration of hCG of 10(5)IU/l or more, which could be a physiological concentration of hCG in sera of normal pregnant women. These results suggest that thyrotropic activity of hCG in sera of normal pregnant women is, at least in a part, mediated by TSH receptors.

Lymphocyte subpopulations and function in childhood IgA nephropathy

In order to examine T lymphocyte function in childhood IgA nephropathy, 13 patients and 10 age-matched control subjects were studied. T lymphocyte function was examined in terms of in vitro immunoglobulin synthesis by peripheral blood mononuclear cells (PBMC) and CD4-depleted (suppressor-rich) and CD8-depleted (helper-rich) PBMC in both unstimulated and pokeweed mitogen (PWM) and Staphylococcus aureus Cowan I (SAC) stimulated cultures. T lymphocyte subpopulations were examined by two-color immunofluorescence analysis using Fluorescein-Activated Cell Sorter (FACS). Children with IgA nephropathy showed (1) a significant increase in IgA synthesis by PBMC with or without mitogen stimulation, (2) a significant increase in IgG and IgA synthesis by CD4-depleted (suppressor-rich) PBMC, (3) a significant increase in IgG and IgA synthesis by CD8-depleted (helper-rich) PBMC, and (4) a significant decrease in suppressor-inducer T cells (Leu3a+Leu8+). These results suggest that a decrease in suppressor-inducer T cells, impaired suppressor T cell function and hyperactivity of helper T cell function are responsible for the increase in IgA production in children with IgA nephropathy.

Serum carnitine and nutritional status in children treated with continuous ambulatory peritoneal dialysis

The serum carnitine (total carnitine), total protein, amino acid, and triglyceride levels were determined in children on continuous ambulatory peritoneal dialysis (CAPD). Compared with levels in controls, serum carnitine levels were significantly decreased in patients on CAPD for more than 4 months, while those of patients on CAPD for 1-3 months were not decreased. Patients on CAPD for more than 4 months also showed lower serum total protein levels than in normal controls. The mean triglyceride levels in patients on CAPD for both 1-3 months and more than 4 months were higher than those in normal controls. Among the amino acids, the serum levels of tryptophan, isoleucine, leucine, tyrosine, valine, serine, and asparagine were significantly lower in patients treated with CAPD than in normal controls, whereas the levels of other amino acids were either increased or not changed. Isoleucine and leucine levels showed a strong correlation with serum carnitine. Our data suggest that malnutrition plays a role in the decrease of serum carnitine levels in patients receiving CAPD.

Human chorionic gonadotropin promotes thyroid growth via thyrotropin receptors in FRTL-5 cells

To ascertain the presence of thyroid growth-promoting activity (TGA) in the sera of pregnant women, we measured TGA in the sera of pregnant women by means of a bioassay based on [3H]-thymidine [( 3H]Tdr) incorporation in cultured rat FRTL-5 thyroid cells. Furthermore, to elucidate the mechanisms of human chorionic gonadotropin (hCG) in promoting the thyroid growth, we evaluated the effects of blocking type TSH receptor antibody (blocking IgGs) from patients with primary hypothyroidism on the activity of hCG. After the PEG-pretreated serum or the serum plus blocking IgGs was incubated for 72 h at 37 degrees C with FRTL-5 cells and [3H] Tdr, [3H] Tdr incorporated in the cells was counted. Although 9 normal pregnant women had normal TGA, two patients with hydatidiform mole, whose hCG levels were 966,500 and 497,100 IU/L, had positive TGA, but the activity showed normal when analyzed with the addition of a blocking IgG. hCG also showed a dose-dependent increase in [3H]Tdr incorporation, and it was inhibited by the addition of blocking IgGs. Furthermore, the inhibition of hCG-induced [3H]Tdr incorporation by 16 blocking IgGs correlated with their TBII and the inhibition activity of hCG-induced cAMP accumulation. Analysis by the Lineweaver-Burk plots of dose response curves of TSH- and hCG-induced [3H]Tdr incorporation showed the same inhibition pattern as with the addition of the same blocking IgGs. In conclusion, 1) hCG-related TGA exists in the sera of some patients with hydatidiform mole; and 2) hCG and the sera of some patients with hydatidiform mole promote thyroid growth, at least in a part, via TSH-receptors in FRTL-5 cells.

Synergistic effect of thyroid hormone and thyrotropin on iodothyronine 5'-deiodinase in FRTL-5 rat thyroid cells

The effects of T3 and T4 on the iodothyronine 5'-deiodinase (5'-D) activity in FRTL-5 rat thyroid cells were investigated. T3 and T4 stimulated the 5'-D activity in a dose-dependent manner. Kinetic studies showed that the stimulation of the 5'-D by T3 was associated with an increase in maximum velocity (Vmax) in [11.9 +/- 0.2 (mean +/- SE) and 25.4 +/- 0.9 pmol I-released/mg protein.min, respectively, in control and cultured with 10(-9) M T3 for four days] but without a change in apparent Michaelis-Menten constant (Km) (94.8 +/- 5.3 nM and 105.4 +/- 12.1 nM, respectively). Furthermore, cycloheximide (5 microM) completely abolished the stimulatory effect of T3 on the 5'-D activity. T3 and T4 also enhanced the 5'-D activity stimulated by TSH in a dose-dependent manner. Kinetic studies showed that the stimulatory effect of T3 on the 5'-D stimulated by TSH was again associated with an increase in Vmax (86.0 +/- 4.0 and 166.5 +/- 1.9 pmol I- released/mg protein.min, respectively, cultured with 0.3 U/liter TSH and cultured with TSH plus 10(-9) M T3 for four days) without a change in apparent Km (114.0 +/- 7.4 nM and 111.6 +/- 12.5 nM, respectively). Cycloheximide (5 microM) completely abolished the stimulatory effect of TSH plus T3 on the 5'-D activity. There were no significant differences observed between cells cultured with TSH and with TSH plus T3 in either the intra- or extracellular cAMP contents. Furthermore, T3 enhanced the 5'-D activity stimulated by (Bu)2 cAMP. These results strongly suggest that T3 or T4 was synergistic with TSH in stimulating the 5'-D activity in FRTL-5 cells, and that cAMP production would be an important component of the synergism.

Thyroid-stimulating activity of human chorionic gonadotropin in sera of normal pregnant women

To ascertain the thyrotropic activity of human chorionic gonadotropin in sera of normal pregnant women, we examined the adenylate cyclase activation in the cultured FRTL-5 cells by extracted hCG from 7 normal pregnant women. hCG was extracted from the sera using anti-hCG-beta subunit monoclonal antibody-coated microwells, eluted with 2 mol/l guanidine-HCl, and reconstituted with hypotonic Hanks' solution. FRTL-5 cells were precultured in 5H medium, incubated for 2 h with the serum extracts, and the cAMP released into the medium was measured. hCG levels in serum extracts ranged from 1100 to 6800 IU/l; values corresponded to 1.4-19.8% compared with those in the original serum samples. Addition of the extracts to FRTL-5 cells resulted in significant increases in the cAMP accumulation, ranging from 9.8 to 59.0 nmol/l. cAMP levels were also increased in a dose-dependent manner by adding purified hCG as well as crude hCG and hTSH to FRTL-5 cells. These findings suggest that the thyroid gland of normal pregnant women may actually be stimulated by hCG itself.

Ciclosporin treatment in children with steroid-dependent nephrotic syndrome

We report our experience with ciclosporin (CS) treatment in 18 children with steroid-dependent nephrotic syndrome. CS was started at 3-5 mg/kg per day after the patients had attained remission with steroid therapy, and was adjusted to maintain a trough blood level of between 250 and 600 ng/ml, being administered for 6 months. Although 1 patient dropped out of the study because of renal dysfunction, the remaining 17 children completed the full trial. No relapse occurred during the 6-month period of CS treatment, and it was possible to discontinue steroid therapy in all patients. However, after discontinuation of CS treatment, nephrotic syndrome relapsed in 16 patients and 14 again had frequent relapses and became steroid-dependent, as before CS treatment. The effect of CS in maintaining remission from steroid-dependent nephrotic syndrome was thus dependent on continuation of CS treatment. Although several side-effects occurred during CS treatment, they were not so serious as to necessitate discontinuation of treatment, except in 1 patient, and all of these side effects were reversible. CS is therefore a new agent for the management of children with steroid-dependent nephrotic syndrome in place of corticosteroid and alkylating agents, although long-term maintenance therapy may be necessary for maintaining longer remission.

A sensitive and practical bioassay for thyrotropin (TSH): comparison of the bioactivity of TSH in normal subjects and in patients with primary hypothyroidism

To study the possible correlation between the bioactivity ratios of the serum TSH and serum thyroid hormone concentrations in patients with primary hypothyroidism, the bioactivity of TSH in these patients was determined by means of a sensitive and practical bioassay and the results were compared to those in normal subjects. Sample sera were obtained from 11 patients with primary hypothyroidism and 9 normal subjects. TSH was extracted from the serum with anti-human TSH monoclonal antibody-coated tubes. The bioassay for TSH was performed by measuring the amount of cAMP released into the medium from cultured FRTL-5 cells incubated with the TSH extract. Linear relations were found between the serum TSH values, measured by the immunoassay, and the bioactivity of the TSH, measured by the present assay, in normal subjects (y = 1.13 x-0.3, r = 0.89, p less than 0.01) and in patients with primary hypothyroidism (y = 0.90 x + 0.7, r = 0.93, p less than 0.01). Moreover, the regression line in patients with primary hypothyroidism was not significantly different from that in normal subjects based on the analysis of covariance. The present findings suggest that the bioactivity of TSH is consistent with the immunoreactivity of TSH in patients with primary hypothyroidism as well as in normal subjects.

Graves' immunoglobulin G stimulates iodothyronine 5'-deiodinating activity in FRTL-5 rat thyroid cells

To elucidate the effect of Graves' immunoglobulin G (IgG) on iodothyronine deiodination in the thyroid, we examined the characteristics of iodothyronine 5'-deiodinating (I-5'-D) activity in FRTL-5 rat thyroid cells and the effect of Graves' IgG on its activity. FRTL-5 cells were sonicated and incubated with 0.5 mumol/L rT3 with a tracer amount of [125I]rT3 in 0.1 mol/L phosphate buffer containing 1 mmol/L EDTA and 0.5 mmol/L dithiothreitol. The released 125I- was separated by Dowex-50WX2 column and counted. The amount of I- released was tissue, incubation time, temperature, and pH dependent, strongly suggesting that the reaction is enzymatic. The activity was completely inhibited by propylthiouracil. The Km value for rT3 was approximately 0.32 microM when analyzed by Lineweaver-Burk plot. TSH, dibutyl cAMP, and Graves' IgG induced I-5'-D activity in a dose-dependent manner. However, cycloheximide (5 mumol/L) abolished the stimulating effects of these agents on I-5'-D activity. These results suggest that TSH, dibutyl cAMP, and Graves' IgG induced I-5'-D activity through the synthesis of new enzyme protein. A significant positive correlation between thyroid-stimulating antibody activity assayed by measuring cAMP production using FRTL-5 cells and I-5'-D activity induced by the Graves' IgG in 10 patients with untreated Graves' disease was observed (r = 0.79; P less than 0.01). The present findings suggest that type I iodothyronine 5'-deiodinase exists in FRTL-5 rat thyroid cells and that Graves' IgG as well as TSH stimulate the activity at least in part by activating adenylate cyclase.

A quantitative analysis of the mesangium in children with IgA nephropathy: sequential study

Quantitative analysis of the mesangial matrix and cells was performed on serial renal biopsies from 41 children with IgA nephropathy. In the repeat renal biopsy, nine patients showed a significant increase of mesangial matrix, 29 showed no change and in three there was a significant decrease. Eight of the nine patients (89 per cent) with a matrix increase had persistent proteinuria at the second biopsy, whereas only 14 of the 32 (44 per cent) without a matrix increase had persistent proteinuria (P less than 0.05). Although the mesangial matrix increased in patients with persistent proteinuria, there was no decrease in patients with clinical remission. In contrast to the mesangial matrix, mesangial cells significantly decreased in 23 patients, did not change in 16, and significantly increased in only two in the second biopsy. These findings suggest that mesangial matrix increase is usually an irreversible change and that persistent proteinuria is associated with matrix increase with worsening in glomerular morphology and clinical outcome. This study indicates the importance of serial renal biopsy in children with IgA nephropathy with persistent proteinuria.

MK4588, a new antibiotic related to xanthocillin

A new antibiotic, MK4588, structurally related to xanthocillin, was isolated from the culture broth of Leptosphaeria sp. L-179. Antibiotic MK4588 exhibited inhibitory activity against a limited range of Gram-positive and Gram-negative bacteria. The antibiotic was degraded by alkali to a more active product. The structures of MK4588 and the degradation product were determined to be (1R*,6S*,7S*)-7-(Z)-(1-isocyano-2-(4-methoxyphenyl]ethenyl-1-hydro xy-7- isocyanobicyclo[4,2,0]oct-2-en-4-one and (Z)-2,3-diisocyano-1-(4-methoxyphenyl)buta-1,3-diene, respectively, by NMR spectral analyses coupled with X-ray crystallographic analysis of MK4588.

Repeat renal biopsy in children with IgA nephropathy

Serial renal biopsy findings in 61 children with IgA nephropathy were correlated with their clinical course. At the time of the second biopsy, 23 patients showed clinical remission defined as complete disappearance of proteinuria and hematuria with normal renal function while 38 had persistent urinary abnormalities with normal renal function at the second biopsy. There were no differences between the two groups with regard to initial clinical findings and pathologic findings of the initial renal biopsy. The second biopsy of patients with clinical remission showed improvement of the glomerular changes on light microscopy, disappearance or diminution of IgA deposits in the mesangium and decrease of electron-dense deposits, whereas the second biopsy of patients with persistent urinary abnormalities showed progression of glomerular changes on light microscopy, persistence of mesangial IgA deposits and persistence of electron-dense deposits. Our study results show the importance of repeat renal biopsy in children with IgA nephropathy with persistent urinary abnormalities, as a progression of glomerular changes is common in these patients. These observations suggest that the deposition of IgA in the mesangium may be responsible for the glomerular damage in children with IgA nephropathy.

Characterization of immobilized hepatocytes as liver support

Hepatocytes isolated from rat liver were immobilized within Ca-alginate. Immobilized hepatocytes could remove ammonia and other toxic substances causing hepatic coma, such as indole, phenol, bilirubin, and short chain fatty acids. Although free hepatocytes lost those activities within 2 days, immobilized hepatocytes maintained those activities for more than 7 days. Immobilized hepatocytes induced tyrosine aminotransferase (TAT) in the presence of dexamethasone and dibutyryl-cAMP and retained the ability to induce TAT for more than 7 days. Biologically active form of coagulation factor II, prothrombin could be synthesized and secreted into medium by immobilized hepatocytes. Moreover, immobilized hepatocytes produced glucose from lactate, alanine, fructose, and galactose. Like adult rat liver, growth-related function and liver-specific function in immobilized hepatocytes were reciprocally controlled by cell density. There are both alpha-, and beta-adrenergic receptors in membrane of liver cells, and the adrenergic action of epinephrine is alpha-predominant in adult rat liver. Monolayer-cultured hepatocytes can not maintain alpha-adrenergic response. However, immobilized hepatocytes maintained alpha-adrenergic response as shown in vivo. Those characteristics of immobilized and three-dimensionally cultured hepatocytes are regarded almost the same as liver cells in vivo. Furthermore, therapeutic effect of immobilized hepatocytes on the hepatic failure were confirmed in the experiment using hepatocytes damaged with D-galactosamine. Therefore, it is suggested that immobilized hepatocytes could be applied to a hybrid artificial liver support.

Immune abnormalities and clinical course in childhood IgA nephropathy

Immunoglobulin production by peripheral blood mononuclear cells (PBMC) and lymphocyte subpopulations were studied in 56 children with IgA nephropathy (IgAN) and 22 healthy controls. All the patients had persistent proteinuria at the time of diagnosis, and were divided into three clinical groups on the basis of urinary findings at the time of examination: 27 patients had proteinuria with or without microscopic hematuria (group A; active stage), 9 had microscopic hematuria only (group B; healing stage) and 20 had normal urine (group C; remission stage). PBMC from the patients in group A cultured without mitogenic stimulation produced significantly more IgA and IgG than those from controls (p less than 0.05). After polyclonal B cell stimulation with pokeweed mitogen (PWM), PBMC from patients in group A produced significantly more IgA than those from group B (p less than 0.05), group C (p less than 0.05) or controls (p less than 0.01), and produced significantly more IgG than those from group B (p less than 0.05) or controls (p less than 0.01). However, there was no significant difference in PWM-stimulated IgG production between groups A and C. PWM-stimulated PBMC from patients in group C produced significantly more IgA and IgG than those from controls (p less than 0.05). There were no significant differences in lymphocyte subpopulations among groups A, B and C and controls. These findings show that the clinical course of childhood IgAN is correlated with IgA production by PBMC suggesting that overproduction of IgA might be responsible for the pathogenesis of IgAN in children.

Thyroid-stimulating activity in sera of normal pregnant women

To evaluate the effect of a thyroid stimulator on thyroid function in the sera of normal pregnant women, we measured thyroid-stimulating activity (TSA) using a highly sensitive bioassay based on cAMP accumulation in cultured rat FRTL-5 thyroid cells. Serum was pretreated with 10% polyethylene glycol (PEG), and the supernatant (PEG-pretreated serum) was then used in the following studies. FRTL-5 cells were preincubated in 5H medium and incubated for 2 h with PEG pretreated serum, and cAMP was measured. All 11 patients with untreated hyperthyroid Graves' disease with strongly positive thyroid-stimulating antibody activity had normal TSA, because only 5.6% of their immunoglobulin G was recovered in the PEG-pretreated serum. In 32 normal pregnant women, 29 (91%) had positive TSA. Their TSA showed statistically significant positive correlations with serum hCG and free T4 levels, and a negative correlation with serum TSH levels. Moreover, when hCG was absorbed from sera by incubation with the solid phase anti-HCG monoclonal antibody, a significant positive correlation was observed between the rate of decrease in hCG and that in TSA. In conclusion, 1) TSA exists in the sera of normal pregnant women, which reflects hCG itself; and 2) thyroid glands of normal pregnant women may be stimulated by TSA to induce a slight suppression of TSH but not sufficient to induce overt hyperthyroidism.

A sensitive and practical bioassay for thyrotropin using cultured FRTL-5 cells: assessment of bioactivity for serum TSH in patients with chronic renal failure

A sensitive bioassay for TSH employing a practical extraction method was developed, and the bioactivities in patients with chronic renal failure receiving hemodialysis were compared with those in normal subjects. Serum samples were obtained from 12 normal subjects and 12 patients with chronic renal failure receiving hemodialysis. TSH was extracted from the serum using anti-human TSH monoclonal antibody coated tubes, followed by elution with 2.0 mol/l guanidine-HC1 solution (pH 3.2). After the eluate had been dialyzed against phosphate buffered saline (pH 7.4) and again against TRIS-HC1 solution (pH 7.4) and then lyophilized, it was reconstituted with hypotonic Hanks' solution. Bioassay for TSH was performed by measuring the levels of cAMP released into the medium from cultured FRTL-5 cells incubated with the extract. The mean immunoreactive recovery rates of TSH from the serum in normal subjects and patients with chronic renal failure were about 42% (+/- 6) and 40% (+/- 2), respectively. The present bioassay was sufficiently sensitive to detect a serum TSH level of 1.0 mU/l when 3.0 ml of serum was used. Extracts from standard sera at concentrations ranging from 1.0 to 10 mU/l added to the culture medium caused significant linear increases in cAMP production. Based on analysis of covariance the regression line between the immunoreactivities and bioactivities of serum TSH in patients with chronic renal failure (y = 0.90x + 0.3, r = 0.92) was not significantly different from that in normal subjects (y = 1.04x + 0.1, r = 0.93).(ABSTRACT TRUNCATED AT 250 WORDS)

Activity of thyroid stimulating antibody and thyroid stimulation blocking antibody determined by radioiodine uptake into FRTL-5 cells

To investigate the pathophysiology of patients with autoimmune thyroid diseases, we measured serum thyroid stimulating antibody (TSAb) activity and thyroid stimulation blocking antibody (TSBAb) activity by determining the radioiodine (125I) uptake into FRTL-5 cells. FRTL-5 cells were pre-incubated for seven days with 5H medium and then incubated for 48 hours with patients' crude IgG prepared by polyethylene glycol precipitation. In order to measure TSBAb, 10 microU/ml TSH was also added. 125I was added one hour before the end of the 48 hour incubation period. After the incubation, the medium was aspirated, and the radioactivity in the cells was counted. In patients with untreated hyperthyroid Graves' disease, TSAb was detectable in 18 of 20 patients, the detectability being 90%, and activity showed a statistically significant positive correlation with TSAb activity determined by c-AMP accumulation. Out of 41 patients with hypothyroidism, TSBAb determined by 125I uptake was positive in six cases, the detectability being 14.6%. The inhibition of 125I uptake by one of these six IgGs was suggested to be at the TSH receptor level because it inhibited TSH induced c-AMP accumulation and showed positive thyrotropin binding inhibitor immunoglobulin (TBI I) activity, but did not inhibit the forskolin- and (Bu)2cAMP-induced 125I uptake. Inhibition of another IgG was suggested at the post-receptor level because it did not inhibit TSH induced cAMP accumulation and showed negative TBI I activity, but inhibited forskolin- and (Bu)2cAMP-induced 125I uptake.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute interstitial nephritis associated with Yersinia pseudotuberculosis infection

We report two cases of acute interstitial nephritis associated with Yersinia pseudotuberculosis infection. The patients had fever, abdominal pain, vomiting and acute renal failure coinciding with elevated agglutination antibody titer for Y. pseudotuberculosis. Renal biopsy revealed interstitial nephritis in both patients. Although it is well known that yersiniosis sometimes affects glomeruli, this is the first report to demonstrate acute interstitial nephritis in patients with Y. pseudotuberculosis infection.

Relationship among thyrotropin (TSH), thyroid stimulating immunoglobulins, and results of triiodothyronine (T3) suppression test in patients with Graves' disease

To investigate the relationship between TSH and abnormal thyroid stimulator(s) in patients with hyperthyroid Graves' disease in whom normal thyroid hormone levels in the serum were maintained by antithyroid drug therapy and in patients with euthyroid Graves' disease, determinations were made of the TSH concentration, action of thyroid stimulating immunoglobulins (TSAb and TBII), and T3 suppression. Out of thirty-three patients with hyperthyroid Graves' disease, twelve patients with subnormal TSH levels were all non-suppressible according to the T3 suppression test results and the detectability of TSAb and/or TBII was as high as 75%. In three out of five patients with euthyroid Graves' disease, the serum TSH level was subnormal. All three showed non-suppressibility in the T3 suppression test and positive action of either TSAb or TBII. One of them became clinically thyrotoxic when the TSAb activity was further increased and TBII became positive, and was therefore diagnosed as having hyperthyroid Graves' disease. The present findings suggest that there are still abnormal thyroid stimulator(s) in patients with hyperthyroid Graves' disease who have low TSH, even if their thyroid hormone concentrations remain normal. Moreover, it is likely that some of the patients with euthyroid Graves' disease are actually in a state of subclinical hyperthyroidism because of the presence of abnormal thyroid stimulator(s).

Hereditary nephritis in children with and without characteristic glomerular basement membrane alterations

Characteristic ultrastructural alterations of the glomerular basement membrane (GBM) have been reported in hereditary nephritis. However, these GBM changes are not present in all patients with hereditary nephritis. In a retrospective study of 42 children with hereditary nephritis characteristic GBM changes were found in 28. The clinical features, renal biopsy findings and subsequent course were compared with those in the 14 without such changes. All 42 patients had hematuria. Eighty-two percent of the patients with the GBM changes showed progression of nephritis and 39% showed neurosensory deafness when last seen. In contrast, all patients without the GBM changes had a normal audiogram, ran a nonprogressive course and had hematuria only when last seen. Light microscopy of renal biopsy specimens revealed segmental glomerular sclerosis and interstitial foam cells only in patients with the GBM changes. Our study shows that the presence or absence of these GBM changes is the most reliable indicator of the prognosis in children with hereditary nephritis.

A sensitive radioimmunoassay for circulating alpha-interferon in the plasma of healthy children and patients with measles virus infection

The mean circulating alpha-interferon of healthy children aged 2 to 13.5 yrs as measured by a radioimmunoassay was 0.119 +/- 0.031 ng/ml, which was significantly lower than that of young adults. Circulating alpha-interferon of children with measles virus infection aged 1 to 11 yrs, on their first visit to the hospital when they were fully symptomatic, was 0.095 +/- 0.035 ng/ml (n = 39). It was 0.105 +/- 0.070 ng/ml (n = 21) on their second visit, 7 to 10 days after their first visit when the patients were convalescent. The difference was statistically insignificant. It is concluded that immunoreactive circulating alpha-interferon is low in children and reaches maximum level in young adults, subsequently declining gradually with age. Immunoreactive circulating alpha-interferon, a possible reflection of endogenous alpha-interferon, does not change significantly by the infection of measles virus.

Benign familial hematuria

Fifty children had benign familial hematuria. They were from 43 families showing neither deafness, heavy proteinuria, nor chronic renal failure and had a nonprogressive course. Light microscopy of renal biopsy specimens showed little or no glomerular changes. Immunofluorescence showed no significant glomerular deposits of immunoglobulins or complement components, but deposition of C3 in the arteriolar walls was observed in 21 of the 39 patients examined. Electron microscopy demonstrated widespread attenuation of the glomerular basement membrane (GBM) in 19 patients, focal attenuation in 22, and normal GBM in nine. These observations suggest that patients with benign familial hematuria are heterogeneous and that the thin GBM may be related to hematuria.

Focal and diffuse membranoproliferative glomerulonephritis in children

Characteristic deposition of C3 has been reported in type I membranoproliferative glomerulonephritis (MPGN). Immunofluorescence microscopy shows diffuse granular deposition of C3 along the majority of capillary loops with lobular pattern. To determine the specificity of this immunofluorescence finding which might aid in distinction between type 1 MPGN, particularly focal MPGN, and the other glomerulopathies, 530 renal biopsies from 437 children were studied retrospectively. Nineteen patients showed diffuse granular deposits of C3 along the capillary walls with lobular distribution. Three patients had lupus nephritis. Nine patients showed the light microscopic changes of diffuse type I MPGN with the characteristic double-walled capillaries. Six patients showed the changes of focal MPGN, and 1 had diffuse mesangial proliferation but without double contours, and they were regarded as examples of a mild or early form of MPGN. A similar deposition of C3 was not seen in the 418 patients with other conditions. We concluded that diffuse granular deposits of C3 along the capillary walls with a lobular distribution appear to be confined to type I MPGN and lupus nephritis and are seen in all patients with diffuse and focal type I MPGN.

Macroscopic hematuria in childhood IgA nephropathy

The clinical presentation, initial laboratory and renal biopsy findings, and subsequent clinical course in 205 children with IgA nephropathy were studied retrospectively. The findings in the 119 patients with macroscopic hematuria and those in the 86 without macroscopic hematuria were compared. There were no differences with regard to sex distribution, age at onset, initial renal function, incidence of hypertension, degree of proteinuria and degree of mesangial proliferation. At the latest follow-up, 3% of the patients with macroscopic hematuria and 8% without macroscopic hematuria had developed chronic renal failure; 8% of the patients with macroscopic hematuria and 20% without had heavy proteinuria with or without hypertension (p less than 0.01); 41% of the patients with macroscopic hematuria and 24% without macroscopic hematuria had normal urine, blood pressure and GFR (p less than 0.05). The disease appears to follow a significantly more benign course in children with macroscopic hematuria than in those without macroscopic hematuria. These observations suggest some macroscopic hematuria-related differences in the natural history of childhood IgA nephropathy.

Hyperamylasemia and S-type isozyme dominance in liver cirrhosis

To investigate the mechanisms of serum amylase abnormalities in liver disease, we determined serum amylase levels, S-type isozyme proportion, clinical symptoms, and laboratory data in 38 cases of histologically confirmed liver cirrhosis and 19 controls. Of the 12 patients who were hyperamylasemic (12/38, 32%), 5 showed S-type isozyme dominance (5/12, 42%), whereas in the 26 normoamylasemic cirrhosis patients, only 5 were S-type isozyme dominant (5/26, 19%). Isozyme percentages were significantly higher (P less than 0.01) in the dominant-S-type cases than in the controls, and S-type dominance was found more frequently in the hyperamylasemic than in the normoamylasemic cirrhosis cases. Only ascites and esophageal varices were observed more frequently as clinical symptoms in the dominant-S-type cases. Our results suggest that amylase is not produced in the human liver, but that the decreased clearance rate of amylase, especially the S-type isozyme, may be a cause of hyperamylasemia and S-type isozyme dominance in cirrhosis.

Mesangial changes in IgA nephropathy in children

The mesangial changes in 92 renal biopsy specimens from 81 children with IgA nephropathy were correlated with the clinical and the other renal biopsy findings. Three types of mesangial changes were identified: mesangial hypercellularity was predominant compared with the increase in matrix in 34 biopsy specimens (type A), the degrees of mesangial hypercellularity and matrix increase were similar in 36 (type B) and matrix increase was predominant in 22 (type C). The interval between the onset of disease and biopsy was significantly shorter in biopsies with type A mesangial changes (P less than 0.01) and significantly longer in those with type C (P less than 0.01). Serial pathologic observations revealed that predominant mesangial hypercellularity was almost exclusively seen in the initial biopsy but predominant matrix increase was usually seen in the follow-up biopsy. The percentage of glomeruli showing sclerosis was significantly higher in biopsies with type C mesangial changes (P less than 0.05). At the latest follow-up, 58% of the patients showing type A and 57% showing type B lost their proteinuria, whereas only 9% showing type C lost their proteinuria (P less than 0.01). These findings suggest that predominant mesangial hypercellularity is characteristic of the early lesion of childhood IgA nephropathy, and progression of disease leads to gradual decrease of mesangial cellularity and increase of matrix with sclerosis.

Nonfamilial hematuria associated with glomerular basement membrane alterations characteristic of hereditary nephritis: comparison with hereditary nephritis

Characteristic ultrastructural alterations of the glomerular basement membrane (GBM) have been reported in hereditary nephritis and in children without a family history of renal disease. The clinical features, renal biopsy findings, and subsequent course were studied retrospectively in 48 children with such GBM changes to compare findings in those with and without a family history of nephritis and to determine the significance of the GBM changes in patients with nonfamilial disease. All 48 patients had hematuria. For 30, there was hematuria in at least one other member of the family (familial hematuria group); for 18, there was no familial incidence. There were no differences between the two groups with regard to clinical and pathologic findings. At the latest follow-up six boys with familial hematuria and three boys with nonfamilial hematuria had reduced renal function, and nine boys with familial hematuria and four boys and one girl with nonfamilial hematuria had neurosensory deafness. Our study results show that children with these GBM changes, with or without a family history of hematuria, tend to have a progressive course, with frequent occurrence of neurosensory deafness, and that the prognosis is more severe in boys. These observations suggest that such GBM changes in patients with nonfamilial hematuria may represent new mutations for hereditary nephritis.

In vitro characterization of various factor VIII concentrates

The in vitro properties of 5 heat-treated Factor VIII (F VIII) concentrates were studied and compared with those of conventional non heat-treated concentrates with special reference to F VIII/von Willebrand Factor (vWF) activities. The heat-treated F VIII concentrates were found to contain about 25 U/ml of F VIII: C as indicated on the label, 59.5-103.3 U/ml of F VIII: Ag, 20.0-74.0 U/ml of ristocetin cofactor activity (RCof), and 67.3-96.0 U/ml of vWF: Ag. The F VIII/vWF activities in the heat-treated concentrates were almost the same as those in the 6 non heat-treated concentrates. The antihemophilic factor (AHF)-cryoprecipitate contained 2.3 U/ml of F VIII: C which was roughly equivalent to the amount of F VIII: Ag. In addition, it contained 7.3 U/ml of RCof which was equivalent to the amount of vWF: Ag. The ratio of F VIII: Ag to F VIII: C in the F VIII concentrates ranged from 2.5 to 4.4. The ratio of vWF: Ag to RCof in the concentrates ranged from 1.1 to 4.8. There were, however, no significant differences in F VIII/vWF activities between the heat-treated and the non heat-treated F VIII concentrates with two exceptions. These findings suggest that the inactivation of the biological activities of F VIII and RCof, and/or the denaturation of both the F VIII: C protein and the vWF protein antigen occurred during the production procedure, while the heat-treatment did not lead to further changes of F VIII/vWF.(ABSTRACT TRUNCATED AT 250 WORDS)

Henoch-Schoenlein nephritis and IgA nephropathy in children: a comparison of clinical course

The clinical presentation, initial laboratory and renal biopsy findings, and subsequent clinical course were studied and compared in 128 children with Henoch-Schoenlein (HS) nephritis and in 206 children with IgA nephropathy. The clinical and pathological findings of the two conditions were similar. After a mean follow-up period of 5 years, 72 patients (56%) with HS nephritis and 67 (32%) with IgA nephropathy showed no demonstrable abnormality, 29 (23%) with HS nephritis and 103 (50%) with IgA nephropathy had minor urinary abnormalities, 7 (5%) with HS nephritis and 26 (13%) with IgA nephropathy had heavy proteinuria and/or hypertension, and 20 (16%) with HS nephritis and 10 (5%) with IgA nephropathy had developed chronic renal failure. A worse outcome was significantly associated with the more severe clinical presentations and more severe glomerular changes by light microscopy in HS nephritis, whereas there was no relationship between the severity of clinical presentation and glomerular changes and prognosis in IgA nephropathy. These findings suggest that HS nephritis is an acute disease and prognosis is associated with the severity of glomerular changes at onset, while IgA nephropathy is a chronic, slowly progressive glomerular disease.

Clinical course of immunoglobulin A nephropathy in children

The clinical presentation, initial laboratory and renal biopsy findings, and subsequent clinical course of IgA nephropathy were studied retrospectively in 200 children, and findings in those with younger onset and older onset were compared. Eighty-three patients were 8 years of age or younger (group 1) and 117 were 9 years of age or older (group 2) at onset. There were no differences between the two groups with regard to sex, initial renal function, incidence of hypertension and macroscopic hematuria, degree of proteinuria, and pathologic findings. At the latest follow-up, two patients in group 1 and eight in group 2 had chronic renal failure, and five patients in group 1 and 21 in group 2 had heavy proteinuria with or without hypertension (P less than 0.01), whereas 36 (43%) patients in group 1 and 29 (25%) in group 2 had normal urine, blood pressure, and glomerular filtration rate (P less than 0.01); the disease followed a significantly more benign course in children with younger onset than in those with older onset. These observations suggest some age-related differences in the natural history of childhood IgA nephropathy.

Immunoelectron microscopic study of childhood IgA nephropathy and Henoch-Schönlein nephritis

Renal biopsy specimens from 11 children with Henoch-Schönlein nephritis and 14 with IgA nephropathy were examined by immunoelectron microscopy. The distribution of IgA reaction product (RP) was found to be similar to that of the electron-dense deposits seen with conventional electron microscopy. Deposits of IgA-RP were present in the mesangium and in the subendothelial region of the peripheral glomerular capillary wall in all patients. Subepithelial deposits of IgA-RP were seen in 12 patients. Deposits of IgG-RP were rare and no deposits of IgM-RP were observed. Deposits of C3-RP were found frequently, although they were smaller and less extensive than deposits of IgA-RP. There was no significant difference between Henoch-Schönlein nephritis and IgA nephropathy with regard to immunoelectron microscopy findings. These observations suggest that Henoch-Schönlein nephritis and IgA nephropathy are both forms of mesangiopathic glomerulo-nephritis caused by immune complexes, mainly composed of IgA.

Lysis of the glomerular basement membrane in children with IgA nephropathy and Henoch-Shönlein nephritis

An electron-microscopic study of the glomerular basement membrane was made on 242 renal biopsies from 222 children with a variety of renal diseases. Lysis of the basement membrane was observed in 16 of the 25 children with Henoch-Schönlein nephritis, 36 of the 72 with IgA nephropathy and one with acute poststreptococcal glomerulonephritis. Lysis was frequently associated with subepithelial dense deposits and polymorphonuclear leukocytes, and these are thought to play a role in the lytic process. There was a significant correlation between the presence of lysis of the basement membrane, the degree of proteinuria and the severity of glomerular changes by light microscopy. These findings suggest that the degree of lysis is an indication of the severity of the disease and lysis is associated with progressive disease and a worse prognosis in Henoch-Schönlein nephritis and IgA nephropathy.