Abalone collagens: immunological properties and seasonal changes of their mRNA levels.

The antisera were raised against pepsin-solubilized abalone collagen and its corresponding gelatin. The reactivity against abalone collagen was higher with the anti-collagen than anti-gelatin antiserum. The two antisera recognized all type I collagens from various vertebrates, whereas these had no reactivity against vertebrate type III and type V collagens. Furthermore, both antisera reacted with only alpha 2(I) chains from chicken, rat, and calf. The strong reactivity was observed against the two antisera in the case of invertebrate and protochordate collagens, especially for turban shell collagen. The seasonal changes of collagen mRNA levels were examined in relation to those of collagen content. Haliotis discus collagens (Hdcols) 1 alpha and 2 alpha coding for abalone collagen pro alpha-chains showed quite similar patterns. The highest mRNA levels in adductor and foot muscles for the two collagens were observed in December and January, in good agreement with the increase of collagen content. The mRNA levels decreased in July and August when collagen content decreased. These results indicate that collagen transcription levels are closely related to collagen contents.

Sclerosing encapsulating peritonitis in pediatric peritoneal dialysis patients.

The aim of this study was to define the incidence and characteristics of sclerosing encapsulating peritonitis (SEP) in pediatric peritoneal dialysis (PD) patients in Japan. A questionnaire was sent to all dialysis units with at least two pediatric PD patients. Among 687 patients registered, 11 cases (1.6%) of SEP were diagnosed. The mean age of patients with SEP at the start of PD was 9.7+/-3.6 years and at SEP diagnosis, 19.1+/-3.8 years. All patients had undergone PD for more than 5 years, and the mean PD duration was 9.6+/-3.3 years. SEP was diagnosed in 6.6% and 12% of patients dialyzed for >5 years and >8 years, respectively. The incidence of peritonitis among patients with SEP was not different from that among the Japanese pediatric registry. All patients had virtually no residual urine volume and 9 had impaired peritoneal ultrafiltration. Peritoneal calcification was the most-frequent radiological finding. Peritoneal biopsy was performed in 7 patients and confirmed sclerotic peritonitis in all. Ten patients transferred to hemodialysis, and only 1 patient underwent surgery. Three patients died. We recommend that patients on PD for more than 5 years who have impaired peritoneal ultrafiltration or peritoneal calcification should be carefully managed as presumptive cases of SEP.

Distribution and characterization of enzymes causing starch degradation in rice (Oryza sativa cv. koshihikari).

The thermal dependency and stability of enzymes producing reducing sugar (RS) were examined in bran, the exterior 13% part (outer endosperm), and the remaining inner endosperm of rice grains. RS-producing enzymes in the inner endosperm showed a higher optimum temperature than those in other parts of the rice grain. Diethylaminoethyl-Sephacel chromatography of crude extracts revealed two peaks of RS-producing activity with different optimum temperatures (60 and 37 degrees C) in all three parts. alpha-Glucosidase (EC 3.2.1.20) and alpha-amylase (EC 3.2.1.1) isoform G were thought to be major components of the RS-producing activities with high and low optimum temperatures, respectively. The peak with a high optimum temperature was a more abundant component in the inner endosperm, compared with other parts of the rice grain. Thus, different parts of rice were found to have distinct enzyme sets having different thermal dependency and to be involved in starch degradation to various sugars.

The occurrence of two types of collagen proalpha-chain in the abalone Haliotis discus muscle.

Acid-soluble collagens were prepared from connective tissues in the abalone Haliotis discus foot and adductor muscles with limited proteolysis using pepsin. Collagen preparation solubilized with 1% pepsin contained two types of alpha-chains which were different in their N-terminal amino acid sequences. Accordingly, two types of full-length cDNAs coding for collagen proalpha-chains were isolated from the foot muscle of the same animal and these proteins were named Hdcols (Haliotis discus collagens) 1alpha and 2alpha. The two N-terminal amino acid sequences of the abalone pepsin-solubilized collagen preparation corresponded to either of the two sequences deduced from the cDNA clones. In addition, several tryptic peptides prepared from the pepsin-solubilized collagen and fractionated by HPLC showed N-terminal amino acid sequences identical to those deduced from the two cDNA clones. Hdcols 1alpha and 2alpha consisted of 1378 and 1439 amino acids, respectively, showing the primary structure typical to those of fibril-forming collagens. The N-terminal propeptides of the two collagen proalpha-chains contained cysteine-rich globular domains. It is of note that Hdcol 1alpha completely lacked a short Gly-X-Y triplet repeat sequence in its propeptide. An unusual structure such as this has never before been reported for any fibril-forming collagen. The main triple-helical domains for both chains consisted of 1014 amino acids, where a supposed glycine residue in the triplet at the 598th position from the N-terminus was replaced by alanine in Hdcol 1alpha and by serine in Hdcol 2alpha. Both proalpha-chains of abalone collagens contained six cysteine residues in the carboxyl-terminal propeptide, lacking two cysteine residues usually found in vertebrate collagens. Northern blot analysis demonstrated that the mRNA levels of Hdcols 1alpha and 2alpha in various tissues including muscles were similar to each other.

A simple WWW interface and quick response system-information query system for cross-sectional body dimensions.

We developed a query and analysis system for normal growth measurement of Japanese children on our WWW server using CGI. It has two subsystems. The first shows standard height and standard weight calculated by height. This subsystem can calculate the difference between measured height and the standard along with deviation and the ratio of measured weight to the standard weight. The second shows standard height, weight, head circumference, and chest circumference. This subsystem can calculate differences between the measurements and the standard as well as deviation. Because of the low amount of output required, very short turn-around time was required. This system also allows use of the same interface no matter which brand terminal is used and has wide reusability. This system will save doctors and nurses the difficulty of looking up a child's data, then having to make the calculation. We also compare the merits of CGI and Java.

Transcapillary ultrafiltration and peritoneal equilibration test in pediatric patients.

The usefulness of the peritoneal equilibration test (PET) in children is unknown. The relationship between transcapillary ultrafiltration and PET was investigated in order to evaluate the usefulness of PET in children. PET was performed on 14 patients undergoing peritoneal dialysis. Their age and bodyweight ranged from 3.8 to 23.6 years and 10.2 to 55.8 kg, respectively. The patients were divided into two groups according to bodyweight; group A patients weighed < or = 40 kg (n = 7) and group B patients weighed > 40 kg (n = 7). There was no significant difference in the mean infusion volume per bodyweight between the two groups, but the mean infusion volume per body surface area was smaller in group A than in group B. Group A showed a more rapid equilibration of dialysate glucose and creatinine than group B. Higher normalized mass transfer area coefficients were evident in group A. In spite of the lower effective glucose gradient in group A, the transcapillary ultrafiltration capacity (TUFC) showed no difference between the two groups. When the slope indices of the regression equations between the two groups were compared, the slopes of the regression in the relationship between TUFC and dialysate (D) ratios D/Do glucose or D/P creatinine in group A were steeper than those in group B. Results of the present study indicate that the larger peritoneal area to infusion volume in patients with smaller body size results in both a rapid equilibration of solutes and sufficient transcapillary ultrafiltration.

The Japanese National Registry data on pediatric CAPD patients: a ten-year experience. A report of the Study Group of Pediatric PD Conference.

OBJECTIVE: Over the past 10 years, we have collected data on pediatric patients less than 16 years of age from the National Registry of CAPD (continuous ambulatory peritoneal dialysis). We present our experience with this population. DESIGN: The database details the patient number, age, weight, height, outcome, cause of death, reason for terminating CAPD therapy, peritonitis, and catheter survival. PATIENTS: Of the 434 patients (239 males, 195 females), 37 patients (8.5%) were under 1 year of age and 164 patients (37.8%) were under 6 years of age. About half of the patients were less than 20 kg in weight, clearly indicating that CAPD was the treatment of choice in young children. The duration on CAPD for these patients was less than 2 years for 233 patients (54%), and was 5 years or more in 48 patients (11%). RESULTS: The outcome of the total patient population of 434 as of May, 1991, is as follows: 229 patients (52.8%) were being successfully treated with CAPD, 47 patients (10.8%) died, and 78 patients (18.0%) received a kidney transplantation. The patient survival rate was 85.6% at 3 years and 81.7% at 5 years. The technique survival rate was 74.9% at 3 years and 63.5% at 5 years. The rate of peritonitis was one episode over 28.6 patient-months. The mean catheter duration was 1.68 years. Peritonitis rate, catheter survival rate, and the rate of tunnel infection were worse in children less than 6 years of age than in older children. CONCLUSION: The excellent patient and technique survival rates indicate that CAPD is an effective treatment for children with end-stage renal disease in Japan. The high infection rates in younger children indicate that extra careful management is needed for this young age group.

Long-term prognosis and prognostic factors of Japanese children with mesangial proliferative glomerulonephritis without IgA deposition.

Mesangial proliferative glomerulonephritis without IgA deposition (non-IgA MesPGN) is commonly detected in biopsy specimens, but the clinicopathological correlation with the long-term prognosis still remains obscure. The aim of our study is to elucidate the long-term prognosis and the clinicopathological prognostic factors in patients with non-IgA MesPGN. We mailed questionnaires to 122 patients with primary glomerulonephritis who were biopsied between 1963 and 1975. Information was obtained from 109 of these 122 patients and 55 were histologically rediagnosed as having non-IgA MesPGN. The histological alterations of glomeruli and tubulointerstitium were classified into five grades. The mean period between the biopsy and the questionnaires was 20.5 years. Six of the 55 patients with non-IgA MesPGN developed end-stage renal failure and histopathological alterations of renal biopsies from these six patients were classified into grade IV or V. The presence of hypertension, heavy proteinuria of over 2+ or renal insufficiency at the biopsy was related to the severe histological changes, a grade of IV or V and to a poor prognosis. The renal survival rate of all the 55 patients was 88.3% at 20 years after the biopsy, while that of the 12 patients with severe histological changes was 48.6%. Although non-IgA MesPGN is considered to be a heterogeneous disease, we cannot ignore the incidence of this disease and thus consider it to be one of the important primary glomerulonephritides that occur in childhood.

Toughness and Collagen Content of Abalone Muscles.

Toughness and collagen content were measured for various muscle parts of the Japanese abalone, kuro-awabi (Haliotis discus), in relation to muscle structures. The dorsal surface of the foot was toughest, followed by the hard and soft part of the foot, then the upper and middle part of the adductor muscle, irrespective of being reared or wild specimens. When compared with other abalone species, kuro-awabi showed the highest toughness for all the muscle parts, followed by madaka (H. sieboldii) and megai-awabi (H. gigas), while ezo-awabi (H. discus hannai) was softest. Collagen content was parallel with muscle toughness: the higher the collagen content, the tougher the muscle. Light micrographs of kuro-awabi showed that foot and the dorsal surface of foot were dominated by connective tissues, while adductor muscle was mainly composed of myofibrils. Transmission electron micrographs demonstrated that myofibrils in the foot were surrounded by thick layers of collagen fibrils of about 1 µm, confirming light microscopic observations.

Genetic control of nonresponsiveness to hepatitis B virus vaccine by an extended HLA haplotype.

We previously reported evidence for a statistical association between the serologically determined HLA-Bw54, DR4 and DRw53 alleles and the non-immune responsiveness to hepatitis B virus surface antigen (HBsAg) in the Japanese population. To identify the locus and allele within the HLA region associated with the nonresponsiveness to HBsAg, serological HLA typing, DNA typing of HLA-DQ and DP alleles using amplified HLA genes and sequence-specific oligonucleotide probes, and restriction fragment length polymorphism (RFLP) analysis of the fourth component of complement (C4) genes were performed in healthy unrelated Japanese vaccinees who were immunized subcutaneously three times with plasma-derived HBsAg vaccine. In nonresponders to HBsAg, the frequencies of HLA-Bw54 cross-reactive epitope group (CREG); (Bw54, Bw55, Bw56 and other Bw22), C4 RFLP (6.5 kb + 12.0 kb), DR4, DRw53 and DQw4 (DQA1*0301-DQB1*0401) were increased and the frequencies of HLA-DR1, DRw6 and DQw1 were decreased as compared with those in healthy unrelated controls. Further analysis revealed that the coexistence of HLA-Bw54CREG and DR4-DRw53-DQw4 (DQA1*0301-DQB1*0401) was associated with the nonresponder group, whereas, donors positive for exclusively either Bw54 CREG or DR4-DRw53-DQw4 (DQA1*0301-DQB1*0401) were not associated with the nonresponder group. Because there is a strong linkage disequilibrium between HLA-Bw54CREG, C4 RFLP (6.5 kb + 12.0 kb) and HLA-DR4-DRw53-DQw4 (DQA1*0301-DQB1*0401) in the Japanese population, the extended HLA-Bw54CREG-C4 RFLP (6.5 kb + 12.0 kb)-DR4-DR-w53-DQw4 (DQA1*0301-DQB1*0401) haplotype may well control nonimmune responsiveness to HBsAg. This extended HLA haplotype controls nonresponsiveness as a dominant genetic trait because all ten heterozygotes and two of three probable homozygotes of this extended HLA haplotype were nonresponders.

Immune status of children on continuous ambulatory peritoneal dialysis.

Immunological parameters including serum IgG, IgA and IgM, lymphocyte phenotypes (CD3, CD4, CD8, HLA-DR+CD3-), natural killer cell activity and lymphocyte proliferation with phytohaemagglutinin were assessed in 10 children on continuous ambulatory peritoneal dialysis (CAPD) and 10 control subjects. Live vaccines were injected into 6 of the 10 children on CAPD (4 had a combined measles-mumps-rubella vaccine and the other 2 mumps vaccine). Serum antibody titres to these viruses were measured before and after vaccination. The serum IgG level was statistically lower in the CAPD group than in the control group (P less than 0.01), but there was no difference in the percentage of HLA-DR+CD3- cells and in the ratio of CD4 to CD8 between the two groups. There were no differences in the other parameters between the two groups. All of the 6 vaccinated children seroconverted, and serious side effects were not noted. Our results suggest that children on CAPD have no significant immune impairment.

The natural history of screening detected IgA glomerulonephritis in children.

The clinical course of 43 children with IgA glomerulonephritis detected by mass urine screening was followed for a mean period of 8.1 years. Histological findings were graded according to the severity of glomerular and tubulointerstitial lesions. There was no correlation in the severity of histological grade and clinical outcome between subjects with microscopic hematuria and those with microscopic hematuria and proteinuria nor between those with and without one or more episodes of macroscopic hematuria during the follow-up period. None of the 35 children with proteinuria less than or equal to 1 g/m2/day had severe histological findings or developed renal impairment. In contrast, the 8 children with proteinuria greater than 1 g/m2/day had moderate and severe histological findings. Four of these 8 children developed hypertension or renal insufficiency during the follow-up period. Our study indicates that the outcome of screening detected IgA glomerulonephritis in children correlates with the level of proteinuria and the severity of renal pathology.

Asymptomatic isolated microhaematuria: natural history of 136 children.

In a mass screening programme, 251 children with isolated microhaematuria were detected. Of these 251 children, 115 were excluded from the study because of microhaematuria secondary to a specific cause. The remaining 136 children were diagnosed as having asymptomatic isolated microhaematuria (ASH). Of these 136 children, 23 had evidence of urinary abnormalities in their family members. Red blood cell casts were evident in 31 children at their initial visit or during the follow-up period. Ten children had one or more episodes of macrohaematuria during the study. Renal biopsy was performed in 19 children because of indications of glomerular disease, and 13 of these 19 children had mild to moderate glomerulonephritis. None of these 136 children developed hypertension or renal impairment after a mean period of 7.4 years (range 6-13 years). Thirty-five children had normal urinary findings within 6 years of their initial visit, and 100 have had persistent microhaematuria without proteinuria throughout the follow-up period. The other child had microhaematuria with proteinuria greater than 1 g/m2 per day at the end of the study. This study suggests that the prognosis of ASH is good, and that renal biopsy is not indicated for children with ASH.

High-dose methylprednisolone therapy for nephrotic syndrome in Henoch-Schoenlein nephritis.

Twelve patients with nephrotic syndrome (NS) in Henoch-Schoenlein (HS) nephritis were treated with a high dose of intravenous methylprednisolone (MP) on each of nine alternate days followed by oral prednisolone for 4 to 6 months. Renal biopsy was performed on 10 of the 12 patients. The glomerular change in 5 patients, which was accompanied by crescents and/or sclerosis, with NS and acute nephritic syndrome (ANS) at onset, was more severe than that of the other 5 patients with NS and hematuria at onset. The renal insufficiency or hypertension in these 5 patients with NS and ANS improved within 2 weeks on this MP therapy. After a mean follow-up period of 40.5 months, all patients except 2 revealed normal physical findings and renal function as well as urinary findings. Repeated biopsies in the 2 patients with NS and ANS at onset demonstrated an improved renal pathology in comparison with their initial biopsies. No severe side effects related to high-dose intravenous MP followed by oral prednisolone therapy were encountered in any of the patients. Our results suggest that high-dose intravenous MP therapy can lead to a favorable outcome in patients with NS in HS nephritis.

Systemic lupus erythematosus of childhood onset: correlation between T cells expressing early and late activation antigens and disease activity.

Correlation between T cell phenotypes, especially activated T cells expressing early (EA1) and late (HLA-DR) activation antigens and clinical features were investigated in 22 patients with systemic lupus erythematosus (SLE) of childhood onset. Percentages of T cells expressing EA1 and HLA-DR in 22 patients with SLE were significantly higher than those in controls. Comparison of T cell phenotypes between patients with active and inactive SLE showed that eight patients with active disease had significantly increased percentages of HLA-DR positive T cells than 14 with inactive disease (P less than 0.01). Serial examinations showed that the percentages of HLA-DR positive T cells were decreased after therapy in seven with active non-renal or active non-renal and renal diseases but not in one with only active renal disease. A possible significance of T cells expressing EA1 and HLA-DR in the management of patients with SLE is discussed.

Recurrent parotid gland enlargement as an initial manifestation of Sjögren syndrome in children.

Recurrent parotid gland enlargement is a common disorder in children, while that of auto-immune aetiology is rare. Three children with recurrent parotid swelling had autoantibodies including antinuclear antibody, anti-SS-A (Sjögren syndrome-A), SS-B (Sjögren syndrome-B) antibodies and rheumatoid factor, abnormal sialograms and lymphocytic infiltration of salivary glands, which were consistent with Sjögren syndrome. Initially, all three lacked symptoms of keratoconjunctivitis sicca. During follow up, two patients developed xerostomia and were diagnosed as having primary Sjögren syndrome. Recurrent parotid enlargement appears to be important as an initial manifestation of Sjögren syndrome in children.