Comparison of neutralization profiles for anti-HCV reactive donor samples with or without detectable HCV RNA.

BACKGROUND AND OBJECTIVES: At Japanese Red Cross (JRC) Blood Centers, all donated blood is screened for hepatitis C virus (HCV) by serological and nucleic acid amplification testing. Donor plasma that tested reactive for anti-HCV by serological test is disqualified even if the donor tests negative for HCV RNA. These test results reflect both true-positive results because of past HCV infection and false-positive results because the cross-reactivity of plasma IgG, which current testing methods are unable to distinguish. To characterize these antibody test results, we examined the neutralizing activity of these plasma samples. MATERIAL AND METHODS: Donor plasma samples that tested reactive for anti-HCV by serological test but negative for HCV RNA (n = 43) were analysed for determining their neutralizing activities measured by the inhibition of the cellular entry of pseudoparticles harbouring HCV envelope glycoproteins (HCVpp). RESULTS: Strong and broad neutralizing activities against HCVpp entry similar to the samples that tested reactive for anti-HCV serological test and positive for HCV RNA (considered to be derived from individuals with chronic HCV infection) were observed in three of 43 plasma samples from donors who tested anti-HCV reactive but HCV RNA negative. CONCLUSION: By examining the neutralizing activities of plasma samples, we identified individuals with a past HCV infection from those in whom we were unable to confirm HCV infection according to the current testing algorithms of JRC, which do not perform anti-HCV confirmatory tests.

A novel mutation of the GATA site in the erythroid cell-specific regulatory element of the ABO gene in a blood donor with the Am B phenotype.

The Am and Bm phenotypes are characterized by weak expression of the A or B antigens, respectively, by red blood cells with a normal expression by the saliva of secretors. Deletion of the regulatory element in the first intron of the ABO gene and disruption of the GATA motif in the element were found to be responsible. In this study, we identified a novel mutation within the GATA motif (G>C substitution at position c.28 + 5830) in the regulatory element of the A allele that might diminish transcription activity causing the generation of the Am B phenotype.

A new transfectant panel cell line-based MoAb-independent antigen capture assay system for detection of CD36 antibody.

BACKGROUND AND OBJECTIVES: CD36 antibody (Ab) causes several disorders: neonatal alloimmune thrombocytopenia, platelet transfusion refractoriness and non-haemolytic transfusion reactions. However, there is no gold-standard test for CD36 Ab. MATERIALS AND METHODS: We developed a transfectant panel cell line-based MoAb-independent antigen capture assay system for detection of CD36 Ab and compared it with the monoclonal antibody-specific immobilization of platelet antigens (MAIPA) system in terms of sensitivity and specificity. RESULTS: Our new system was characterized by (1) gene-transfected cell lines, but not panel platelets; (2) not being hampered by HLA Abs; and (3) no need to use CD36 MoAbs to ensure the antigen specificity of this detection system. In addition, it showed a much better receiver operating characteristic curve than the MAIPA system. CONCLUSIONS: The present results indicate that our new system permits highly sensitive and specific detection of CD36 Ab.

Significant background rates of HBV and HCV infections in patients and risks of blood transfusion from donors with low anti-HBc titres or high anti-HBc titres with high anti-HBs titres in Japan: a prospective, individual NAT study of transfusion-transmitted HBV, HCV and HIV infections.

BACKGROUND: The Japanese Red Cross (JRC) conducted a prospective study to evaluate the frequency of transfusion-transmitted HBV, HCV and HIV infections to assess the risk of transfusion of blood components routinely supplied to hospitals. STUDY DESIGN AND METHODS: Post-transfusion specimens from patients at eight medical institutes were examined for evidence of infection with HBV (2139 cases), HCV (2091) and HIV (2040) using individual nucleic acid amplification testing (NAT). If these specimens were reactive, pre-transfusion specimens were also examined for the virus concerned by individual NAT. In the event that the pre-transfusion specimen was non-reactive, then all repository specimens from implicated donors were tested for the viruses by individual donation NAT. In addition, a further study was carried out to evaluate the risk of transfusion of components from donors with low anti-HBc titres or high anti-HBc with high anti-HBs titres. RESULTS: Transfusion-transmitted HCV and HIV infections were not observed. One case of post-transfusion HBV infection was identified (rate, 0·0004675; 95% CI for the risk of transmission, 1 in 451-41,841). The background rates of HBV, HCV and HIV infections in patients prior to transfusion were 3·4% (72/2139), 7·2% (150/2091) and 0% (0/2040), respectively. Sixty-four anti-HBc- and/or anti-HBs-reactive blood components were transfused to 52 patients non-reactive for anti-HBc or anti-HBs before and after transfusion (rate, 0; 95% CI for the risk of transmission, <1 in 22). CONCLUSION: This study demonstrated that the current criteria employed by JRC have a low risk, but the background rates of HBV and HCV infections in Japanese patients are significant.

Na+ modulates the K+ permeability and the membrane potential of alkalophilic Bacillus.

In the absence of Na+ in the medium, the membrane potential of obligately alkalophilic Bacillus cells was found to be decreased by the addition of K+ to the medium, whereas K+ addition in the presence of Na+ had no effect. Rb+ showed essentially the same effect as K+. The decreased membrane potential was quickly restored by lowering the K+ concentration in the medium or by adding Na+ or Li+ to the medium. Thus, in the absence of Na+, the membrane potential of alkalophilic Bacillus seems to be affected by the concentration difference of K+ between inside and outside of the cell, and Na+ or Li+ in the medium suppresses the K+ effect. An exchange between extracellular Rb+ and intracellular K+ was observed in the absence of Na+. However, the exchange was greatly suppressed by the addition of Na+ or Li+ to the medium, indicating that Na+ in the medium modulates the K+ permeability of the alkalophilic Bacillus cell membrane. The K+-induced decrease in the membrane potential of alkalophilic Bacillus in the absence of Na+ is accounted for by the increased K+-permeability of the cell membrane.

Relationship between Na+-dependent cytoplasmic pH homeostasis and Na+-dependent flagellar rotation and amino acid transport in alkalophilic Bacillus.

The cytoplasmic pH homeostasis of alkalophilic Bacillus strains required the presence of Na+ in the medium, and Li+ was found to be equivalently substitutable for Na+. Flagellar rotation and amino acid transport of these bacteria also required Na+ but Li+ was not substitutable for Na+. Na+ concentration of about 1 mM was enough for the cytoplasmic pH homeostasis, while more than 10 mM Na+ was required for the full activities of flagellar rotation and amino acid transport. The addition of 150 mM ethanolamine to the cells at pH 9.6 disrupted the pH homeostasis and increased the cytoplasmic pH close to the external pH. Under this condition, however, flagellar rotation and amino acid transport were not so much affected. Thus, it is clear that flagellar rotation and amino acid transport themselves require the presence of Na+ in the medium, independent of the Na+-dependent cytoplasmic pH homeostasis.

Stereoselective syntheses of the C'D'E'F'-ring system of maitotoxin and the FG-ring system of gambierol.

[structure: see text]. The stereoselective syntheses of the C'D'E'F'-ring system of maitotoxin and the FG-ring system of gambierol were accomplished. The key steps involve 6-endo-cyclization of methylepoxide, SmI2-induced reductive cyclization, 6-endo-cyclization of vinylepoxide, and formation of the lactone ring.

Chromatographic profiles of urinary isoenzymes in healthy children.

Urinary excretion of alkaline phosphatase, gamma-glutamyltransferase and lactate dehydrogenase was studied in a carefully selected group of 155 healthy children, 83 females and 72 males. Enzyme activity was assayed in randomly collected urine samples after gel filtration of the urine specimens. On chromatograms, urinary enzymes of alkaline phosphatase, gamma-glutamyltransferase and lactate dehydrogenase were separated into 4, 2 and 5 isoenzymes, respectively. Mean values of alkaline phosphatase, gamma-glutamyltransferase and lactate dehydrogenase activity were 4.59, 21.6 and 10.0 U/g creatinine. There were no sex-related differences besides lactate dehydrogenase which showed a higher excretion in females than in males. The excretion of urinary enzymes clearly decreased with increasing age.

Discordant phenotypic expression of Alport syndrome in monozygotic twins.

BACKGROUND: Alport syndrome is a genetically heterogeneous disorder, but most patients showed the X-linked form resulting from mutations in the COL4A5 gene. A few cases of mosaicism in Alport syndrome have been reported. METHODS: We describe the case of an 8-year-old boy with mosaicism in Alport syndrome. Punch skin biopsies were obtained from the patient's mother and monozygotic twin brother. Five biopsy specimens from non-Alport patients were used as controls. Immunohistochemical analysis was performed using rat monoclonal antibodies towards individual collagen IV(NC) domains. RESULTS: Kidney tissue of the patient showed: mosaic expression of alpha3(IV), alpha4(IV) and alpha5(IV) in the glomerular basement membrane (GBM), distal tubular basement membrane (TBM) and Bowman's capsule; mosaic alpha6(IV) expression in the Bowman's capsule and distal TBM; and well-preserved expression of alpha1(IV) and alpha2(IV). The patient's skin exhibited mosaic alpha5(IV) expression. His mother and monozygotic twin brother disclosed a normal linear staining of alpha5(IV) in their epidermal basement membranes. This unusual mosaicism of alpha3(IV), alpha4(IV), alpha5(IV) and alpha6(IV) is consistent with a pattern of female heterozygotes of Alport syndrome. CONCLUSION: This discordant phenotypic expression of Alport syndrome in monozygotic twins with unaffected parents suggests possible somatic mosaicism in the COL4A5 gene.

Secondary erythrocytosis associated with distal renal tubular acidosis.

AIMS: Diagnosis and classification of renal tubular acidosis (RTA) have traditionally been made on the basis of functional studies. Despite recent expanding knowledge about the molecular abnormalities involved in renal bicarbonate (HCO3-) and H+ transport, the pathophysiology of secondary erythrocytosis in association with distal RTA remains obscure. CASE HISTORY: A 2-month-old boy with severe hyperchloremic metabolic acidosis with positive urine anion gap was diagnosed with distal RTA. Replacement therapy with sodium bicarbonate and potassium citrate succeeded in improving his metabolic acidosis and growth. His renal function remained normal. He had persistent erythrocytosis. CONCLUSION: Secondary erythrocytosis is a rarely reported association of distal RTA. It may increase the risk of thromboembolism.

Decrease of mesangial matrix after immunosuppressive therapy in children with reversible membranoproliferative glomerulonephritis type I.

We followed the course of membranoproliferative glomerulonephritis (MPGN) type I after immunosuppressive therapy in 10 children. At diagnosis all patients had abnormal urinary findings. After a mean follow-up of 14 years all but one patient showed normal urinalysis and renal function. Glomerular morphometry revealed an increase in the ratio of mesangial matrix area to glomerular area (M/G%) in all patients. After immunosuppressive treatment, a second biopsy was performed, which showed a significantly decreased M/G% in 4 patients. In 3 of the remaining 6, the mean M/G% was significantly lower in a third biopsy when compared with the first. In addition, there was a negative correlation between M/G% and duration from onset disease to biopsy (r = -0.46, p <0.05). Fifteen biopsies (6 initial and 9 repeat biopsies) were examined for the staining of various extracellular matrices. In the initial biopsy type IV collagen, type V collagen and fibronectin were increased in expanded mesangial areas. Type III collagen was found segmentally in a few biopsies only. M/G% correlated with the grade of type IV collagen, type V collagen and fibronectin staining. These findings suggest that a reversible clinical course of MPGN type I in children is paralleled by a decrease of mesangial matrix expansion.

Response of unresectable pancreatic cancer to intraoperative radiotherapy.

Eight patients with unresectable pancreatic cancer were treated by intraoperative radiotherapy (IORT) with electron beams, and the tumor responses were followed using serial CT scans. In five cases, external beam irradiation with 10 MV X-rays was added. While there was no evident change after 2-3 weeks, 6-8 weeks after IORT partial responses were noted in all five examined cases. Furthermore, 12-16 weeks after IORT, three out of five examined patients showed good tumor response with more than 75% regression. Mean survival time was 8.0 +/- 2.7 months. Two patients who lived longer than 1.5 years had shown excellent tumor responses. Serial CT scans in the early period following IORT allowed accurate estimation of the tumor response, which might predict some long-surviving cases.

[Serum IgA-fibronectin complex in children with various renal diseases].

IgA-Fibronectin complex (IgA-FN) has been found in the circulation of patients with IgA nephropathy (IgAN). It has been suggested that circulating IgA-FN is related to IgA deposits in the mesangial area following mesangial matrix expansion in IgAN. We investigated serum IgA-FN in patients with various renal diseases, and examined the relationship between IgA-FN and the clinico-pathological findings. Serum IgA-FN level was measured by enzyme-linked immunosorbent assay (ELISA) in 35 patients with IgAN, 20 patients with Henoch-Schönlein purpura nephritis (HSPN), and other various renal diseases in children. IgA-FN in patients with IgAN was significantly higher than in healthy subjects and patients with minimal change nephrotic syndrome. However some patients with membranoproliferative glomerulonephritis and lupus nephritis had a high level of IgA-FN. The increase in IgA-FN was correlated with macroscopic hematuria and the degree of proteinuria and mesangial matrix expansion in IgAN. Thus, we concluded that the level of IgA-FN is associated with mesangial matrix expansion.

[A structure of ordering and display system by adopting computer for receipt in a medical clinic].

Online and display system for the result of laboratory examination were constructed by adopting a computer for receipt. The computer for receipt was expanded to a new schedule file and a management schedule file. Consequently, reservation system of medical clinic was made and check seats of order decreased in number. It was considered that patients can understand conditions of their illness and results of laboratory examination very easily with this system.

[Clinical study of serum enzyme and metabolic changes after extracorporeal circulation--comparison with the surgery of aortic aneurysm].

The changes of serum enzyme and metabolism were studied by comparing the serial change among three groups. The first group consisted of twenty seven patients treated by surgery under extracorporeal circulation. The second group of ten patients of thoracic aortic aneurysm treated under temporary bypass and the third group of nineteen patients of abdominal aortic aneurysm under aortic cross clamp. The following results were obtained: The enzyme of serum GOT, LDH and CPK increased postoperatively in the all groups, the changes after surgery being greater in the group 1 than the other groups. The metabolism of lactic acid and glycolipid was depressed in the group 1 higher than the other groups. The tissue injury of total body after surgery with extracorporeal circulation was greater than the other groups without extracorporeal circulation. And these results suggest the necessary of improvement of circuit and perfusion technique of extracorporeal circulation.