Proficiency testing with uncertainty evaluation for measuring activities per unit mass of 134Cs and 137Cs in brown rice in Japan.

In Japan, we conducted proficiency testing of activity measurement by using high-purity germanium detectors for 134Cs and 137Cs in brown rice grains. Among 176 reported results, 86 % (for 134Cs) and 93 % (for 137Cs) of the results satisfied |En| â‰¦ 1. However, 58 reports for 134Cs and 51 reports for 137Cs had some failures in their evaluations of uncertainties. The proficiency testing was effective to improve the ability of uncertainty evaluation.

Superagonistic CD28 antibody induces donor-specific tolerance in rat renal allografts.

The ultimate goal of organ transplantation is to establish graft tolerance where CD4+CD25+FOXP3+ regulatory T (Treg) cells play an important role. We examined whether a superagonistic monoclonal antibody specific for CD28 (CD28 SA), which expands Treg cells in vivo, would prevent acute rejection and induce tolerance using our established rat acute renal allograft model (Wistar to Lewis). In the untreated or mouse IgG-treated recipients, graft function significantly deteriorated with marked destruction of renal tissue, and all rats died by 13 days with severe azotemia. In contrast, 90% of recipients treated with CD28 SA survived over 100 days, and 70% survived with well-preserved graft function until graft recovery at 180 days. Analysis by flow cytometry and immunohistochemistry demonstrated that CD28 SA induced marked infiltration of FOXP3+ Treg cells into the allografts. Furthermore, these long-surviving recipients showed donor-specific tolerance, accepting secondary (donor-matched) Wistar cardiac allografts, but acutely rejecting third-party BN allografts. We further demonstrated that adoptive transfer of CD4+CD25+ Treg cells, purified from CD28 SA-treated Lewis rats, significantly prolonged allograft survival and succeeded in inducing donor-specific tolerance. In conclusion, CD28 SA treatment successfully induces donor-specific tolerance with the involvement of Treg cells, and thus the therapeutic value of this approach warrants further investigation and preclinical studies.

Transcription factor Ets-1 is essential for mesangial matrix remodeling.

Most advanced glomerular diseases are characterized by abnormal extracellular matrix (ECM) accumulation in the glomeruli, and matrix metalloproteinases (MMPs) play a pivotal role in ECM remodeling in various glomerular diseases. The proto-oncogene, ets-1, is a transcription factor regulating the expression of various matrix proteinases, including MMP-1, MMP-3, and MMP-9. The goal of the present study was to characterize the role of Ets-1 in the progression of glomerular diseases. Overexpression of Ets-1 in cultured mesangial cells prevented transforming growth factor (TGF)-beta-induced inhibition of DNA-binding activity and TGF-beta-induced type I collagen production. In addition, exogenous Ets-1 abolished TGF-beta-induced collagen gel contraction. The in vivo transfection of the ets-1 gene into nephritic kidney resulted in the increases in glomerular MMP-1, MMP-3, and MMP-9 mRNA, decreases in mesangial ECM deposition, and attenuation of fibronectin extradomain A (EDA) and type I collagen expression. In contrast, knockdown of Ets-1 in glomeruli resulted in severe ECM deposition in diseased glomeruli. In conclusion, Ets-1 promotes degradation of ECM proteins and is critical for integral glomerular reorganization.

Electroporation-mediated HGF gene transfection protected the kidney against graft injury.

The annual rate of kidney graft loss caused by chronic allograft nephropathy (CAN) has not improved over the past decade. Recent reports suggest that acute renal ischemia results in development of CAN. The goal of the present study was to assess the renoprotective potential and safety of hepatocyte growth factor (HGF) gene transfer using a porcine kidney transplant warm ischemia injury model. Following left porcine kidney removal, 10 min of warm ischemic injury was intentionally induced. Next, the HGF expression vector or vehicle was infused into the renal artery with the renal vein clamped ex vivo, and electric pulses were discharged using bathtub-type electrodes. Kidney grafts were then transplanted after removing the right kidney. Histopathological examination of vehicle-transfected kidney transplant revealed initial tubular injury followed by tubulointerstitial fibrosis. In contrast, HGF-transfected kidneys showed no initial tubular damage and no interstitial fibrosis at 6 months post-transplant. We conclude that electroporation-mediated ex vivo HGF gene transfection protects the kidney against graft injury in a porcine model.

Exploring RNA interference as a therapeutic strategy for renal disease.

The short synthetic interfering RNA duplexes (siRNAs) can selectively suppress gene expression in somatic mammalian cells without nonselective toxic effects of double-stranded RNA (dsRNA). However, a selective in vivo delivery of siRNA transfer has not been reported in kidney. Here, we investigated whether injection of synthetic siRNAs via renal artery followed by electroporation could be effective and therapeutic in silencing specific gene in glomerulus. We investigated the effect of siRNA in rat cultured mesangial cells (MCs) and showed that siRNA sequence-specific suppression of transgene expression was over a 1000-fold more potent than that by antisense oligodeoxynucleotide (ASODN). Transfection of siRNA targeting luciferase into rat kidneys significantly inhibited expression of a cotransfected luciferase expression vector in vivo. The delivery of siRNA targeting enhanced green fluorescent protein (EGFP) in the transgenic 'green' rat reduced endogenous EGFP expression, mainly in glomerular MCs. Furthermore, RNAi targeting against TGF-beta1 significantly suppressed TGF-beta1 mRNA and protein expression, thereby ameliorated the progression of matrix expansion in experimental glomerulonephritis. In addition, vector-based RNAi also inhibited TGF-beta1 expression in vitro and in vivo. In conclusion, siRNA-directed TGF-beta1 silencing may be of therapeutic value in the prevention and treatment of fibrotic diseases.

Nucleotide sequence of hepatitis B virus isolated from subjects without serum anti-hepatitis B core antibody.

The nucleotide sequences of the precore/core and X open reading frames (ORFs) of hepatitis B virus (HBV) were studied in four subjects who were serologically negative for anti-hepatitis B core antibody. These subjects were positive for serum hepatitis B surface antigen and were considered to be asymptomatic HBV carriers. Sequencing of the precore/core ORF revealed precore wild type and 3 to 8 nucleotide substitutions (replacing 0 to 2 amino acids) in the core region compared with the sequence of subtype adr. These substitutions were not considered to have changed the epitope of the core antigen, resulting in the absence of anti-HBc as determined by a conventional diagnostic kit. The X ORF showed 1 to 5 nucleotide substitutions (replacing 1 to 3 amino acids) and the structure of the X protein and the core promoter/enhancer II complex appeared to be conserved. These findings strongly suggest that the absence of serum anti-HBc is not due to mutation of the HBV DNA but to an aberrant immune reaction of the host to HBV.

Transmission of hepatitis C virus from mothers to infants: its frequency and risk factors revisited.

A total of 16,714 pregnant Japanese women were tested for antibodies against hepatitis C virus (HCV), and 163 (0.98%) were positive. None of these were infected with human immunodeficiency virus-1 (HIV-1). We conducted a prospective study to discover the rate of HCV infection in babies born to mothers who were HCV RNA-positive but had no evidence for hepatitis (so called "asymptomatic carriers"), and only 2 (2.3%) of 87 such babies became infected during follow-up. This rate was considerably lower than those from other reports which included mothers with clinically overt chronic hepatitis C. We conducted another study to follow babies born to mothers with chronic hepatitis C, and found two babies infected. All of the four infected babies were born to mothers who had HCV RNA in their circulations around delivery at high titers (greater than 5.0 x 10(6) Eq/ml by branched DNA assay). This confirmed the previous finding that virus load was an important risk factor. In addition, we found three families where mother-to-infant HCV transmission was suspected in a retrospective study by indexing HCV-infected pediatric patients. Throughout the seven families, siblings of infected babies were free from HCV infection, suggesting that maternal infection of HCV owes much to chance. Breast milk feeding was not regarded as a risk factor. We also assessed the prevalence of anti-HCV antibody among 6-year old children, and only 10 of 10,446 (0.1%) were positive, suggesting low frequency of HCV infection during the period from birth to this age.

Hepatitis C virus genotypes, reactivity to recombinant immunoblot assay 2 antigens and liver disease.

To clarify the relationship between hepatitis C virus (HCV) genotypes and liver disease, we typed HCV genomes in the sera of 151 blood donors, 180 patients with type C chronic liver disease (CLD), and 30 haemophiliacs residing in Hiroshima, Japan. All of the subjects were positive for anti-HCV and HCV-RNA, and were examined for seroreactivity to HCV-specific antigens. The HCV genotypes were determined by polymerase chain reaction (PCR) with type-specific primers deduced from the putative core region of the HCV genome. Significantly more (P < 0.001) type III HCV was found in the samples from the CLD patients (80%) than in those from the blood donors (55%). Significantly more (P < 0.001) type III HCV was found in the samples from the blood donors (29.1%) than in those from the CLD patients (11.7%). There was no significant difference in the distribution of the HCV types among the patients with chronic active hepatitis, liver cirrhosis, and hepatocellular carcinoma. A four-antigen recombinant immunoblot assay (RIBA-2) assay was used to compare the serum samples for their reactivity to a range of structural and nonstructural peptides specific for HCV (5-1-1, C100-3, C33c, and C22-3). The frequency of seropositivity to 5-1-1 and C100-3 was significantly higher (P < 0.001) in type II HCV-infected blood donors than in type III HCV-infected donors (68.2% and 65.9% vs. 4.5% and 22.7%, respectively). Among the type III HCV-infected individuals, the CLD patients had a significantly higher (P < 0.01) frequency of seropositivity to 5-1-1 than the blood donors (33.3% vs. 4.5%).(ABSTRACT TRUNCATED AT 250 WORDS)

Quantitative analysis of occlusal balance in intercuspal position using the T-Scan system.

The T-Scan system was used to evaluate the distribution of time and force in occlusal balance. Sixty normal subjects demonstrated bilateral balance and an anteroposterior center of force in the first molar region. However, patients with craniomandibular disorders demonstrated marked differences from the control group. The T-Scan system was found to be clinically useful as a diagnostic screening method for occlusal stability in intercuspal position.

[Prevalence of anti C100-3 and HBsAg in blood donors--comparative study of total collected blood units, total collection adjusted to exclude repeat blood donations, and in first time blood donors].

Prevalence of anti C100-3 and HBsAg in donor blood collected at the Hiroshima Red Cross Blood Center during the period of Aug., 1990 to July, 1991 was studied in three groups--total received blood units (187,532 units) without any adjustment, blood units after adjustment by excluding repeat donations of blood units by the same donors (142,160 units), and blood units of first time donors (28,596 units). The results of the study is summarized as follows. 1) There was no significant difference in the prevalence of anti C100-3 between the group comprising the total collected units, and the group after the adjustment. This result suggests that repeat donors do not necessarily belong to any fixed age group. 2) The prevalence of HBsAg is significantly higher in the first time donor group than in the other two groups. In both the total blood units group and the group after the adjustment, prevalence of HBsAg among older age groups was as low as that of younger age groups. This is presumably because of the introduction of selective exclusion of HBsAg positive subjects from donors since 1980. When data from blood donors are used for the epidemiological studies of viral infection among healthy subjects, it is important to know the characteristics of such donor subjects and whether or not they are pre-screened for the viral markers in question.

Prevalence of antibody to Chlamydia pneumoniae TWAR in japan.

Chlamydia pneumoniae TWAR is a newly recognized Chlamydia species that is a pathogen of respiratory tract infection. To clarify the endemic status of C. pneumoniae in Japan, we evaluated the incidence of C. pneumoniae antibody in 1,330 serum samples (660 from outpatients, 600 from normal individuals, and 70 from cord blood). The antibody titer was determined by a microimmunofluorescence test by using the elementary body of C. pneumoniae TW-183 as the antigen. Immunoglobulin G antibody titers of 1:32 or higher were regarded as evidence of past infection. The detection rate of C. pneumoniae antibody rapidly increased in subjects between the ages of 4 and 7 years, reached 44% in subjects between the ages of 8 and 11 years, and was about 50% in older subjects. The rate did not differ between healthy subjects and outpatients. These results suggest that C. pneumoniae infection is highly endemic in Japan as it is in Western countries. However, the antibody prevalence was high in the low age groups in Japan compared with that in Western countries.

[Laboratory and clinical studies of cefmenoxime in the pediatric field].

Laboratory and clinical studies were performed on cefmenoxime (CMX), a new cephalosporin antibiotic, and the following results were obtained. 1. Susceptibility of clinically isolated bacteria to CMX and cefotiam (CTM) or cefazolin (CEZ) Antimicrobial activity of CMX was compared with that of CTM and CEZ against S. aureus, S. epidermidis, S. pneumoniae, H. influenzae and E. coli. CEZ and CTM were more active than CMX against S. aureus, S. epidermidis and S. pneumoniae. But CMX was found to be more active by 1-10 tubes than CEZ and CTM against H. influenzae and E. coli. 2. Clinical efficacy. CMX was intravenously administered to 19 patients; 3 with lacunar tonsillitis, 2 with acute bronchitis, 8 with bronchopneumonia, 3 with UTI, 1 with septicemia, 1 with acute panperitonitis, 1 with S.S.S.S. at daily doses of 30-115 mg/kg (64.6 mg/kg on an average) t.i.d. or q.i.d. for 3-17 days (6.1 days on an average). The overall efficacy rate was 94.7%, i.e., efficacy was excellent in 10 cases (52.6%), good in 8 cases (42.1%), and poor in 1 case (5.3%). Bacteriological efficacy was good, i.e. 16 of the 19 strains disappeared. Transient eosinophilia was observed in 1 patient, but no other laboratory abnormality was observed during treatment. The above results suggest that CMX is 1 of the useful antibiotics in treatment of pediatric infections, especially due to Gram negative bacteria.

[Clinical results of cefoperazone in pediatric infections (author's transl)].

In order to evaluate effectiveness of cefoperazone (CPZ) in the treatment of bacterial infections of children, the clinical studies were carried out. CPZ was administered by one-shot injection to 28 patients at daily dose of 50 approximately 160 (average 89.7) mg/kg in 3 approximately 4 divided dose for 2 approximately 10 (average 5.6) days. The overall efficacy rate in 28 cases was 92.9%, i.e., excellent in 16 (57.1%), good in 10 (35.7%), fair in 1 (3.6%) and poor in 1 case (3.6%). Temporary rise of GOT and GPT or only GOT was observed in each 1 case out of 28 cases (7.1%), but any other abnormality was not observed throughout this series. Based on the above results, CPZ was thus considered to be a useful antibiotic in treatment of pediatric infections caused by Gram-positive cocci and Gram-negative rods.