Predictive markers for hepatic veno-occlusive disease after hematopoietic stem cell transplantation in adults: a prospective single center study

Hepatic veno-occlusive disease (VOD) is a major complication after hematopoietic stem cell transplantation (HSCT). Aetiological determinants, diagnosis and treatment remain unclear. Changes in coagulation-fibrinolysis parameters and N-terminal propeptide for type III procollagen (P-III-P) have been studied in patients with or without VOD after HSCT. We prospectively measured protein C activity, tissue plasminogen activator (t-PA), antithrombin III (AT-III), plasminogen activity (PLG), thrombin-antithrombin III (TAT), alpha2-plasmin inhibitor (alpha2-PI),fibrinogen (Fbg) and P-III-P in 44 consecutive adult patients undergoing allogeneic HSCT. Each parameter was determined before conditioning, on day 0 of HSCT and weekly for 5 weeks. Five of the 44 patients developed VOD at a median post HSCT of day 3 (range, day 3 to 12). On repeated analysis of variance (ANOVA), there were significant differences between patients with and without VOD in P-III-P (P < 0.0001), protein C (P < 0.0001), t-PA (P < 0.0001), PLG (P < 0.0001), AT-III(P < 0.0001), Fbg (P < 0.0001), alpha2-PI (P = 0.0002). Levels of P-III-P were significantly higher in patients with VOD than without VOD, before preparative chemotherapy (P < 0.005) and on days 0 and 7 (P < 0.001). On day 0, levels of t-PA were significantly higher in patients with VOD than without VOD (P < 0.05). On day 7, levels of protein C were significantly lower in patients with VOD than without VOD (P < 0.01). On day 0, there were trends of differences (P = 0.0515) between patients with and without VOD in the levels of protein C. These results suggest P-III-P, t-PA and protein C are predictive markers for VOD after HSCT in adults. Moreover, the serum P-III-P level before start of conditioning might indicate patients at risk for developing VOD.

Induced expression of sarcotoxin IA enhanced host resistance against both bacterial and fungal pathogens in transgenic tobacco

We demonstrate here that induced expression of sarcotoxin IA, a bactericidal peptide from Sarcophaga peregrina, enhanced the resistance of transgenic tobacco plants to both bacterial and fungal pathogens. The peptide was produced with a modified PR1a promoter, which is further activated by salicylic acid treatment and necrotic lesion formation by pathogen infection. Host resistance to infection of bacteria Erwinia carotovora subsp. carotovora and Pseudomonas syringae pv. tabaci was shown to be dependent on the amounts of sarcotoxin IA expressed. Since we found antifungal activity of the peptide in vitro, transgenic seedlings were also inoculated with fungal pathogens Rhizoctonia solani and Pythium aphanidermatum. Transgenic plants expressing higher levels of sarcotoxin were able to withstand fungal infection and remained healthy even after 4 weeks, while control plants were dead by fungal infection after 2 weeks.

Herpes zoster in immunocompetent and immunocompromised Japanese children

BACKGROUND

To confirm epidemiological features of herpes zoster among children with or without immunosuppression, herpes zoster patients who had presented to this hospital were retrospectively investigated.

METHODS

Medical records were reviewed for the 92 cases of pediatric herpes zoster patients diagnosed during the period from 1981 to 1998. The age at onset of herpes zoster and of varicella, the interval between varicella and zoster, the dermatomal distribution of herpes zoster and complications were compared between immunocompetent and immunocompromised children.

RESULTS

The mean age at onset of zoster in immunocompetent children was 8.5 +/- 4.0 years and in immunosuppressed children was 9.7 +/- 3.8 years. The age at onset of varicella was significantly lower (1.6 +/- 1.8 years) in immunocompetent than in immunosuppressed children (4.6 +/- 2.7 years). The interval between varicella and zoster was 6.2 +/- 3.2 years in immunocompetent children. More than 80% of patients with acute leukemia or malignant lymphoma had herpes zoster within 2 years after diagnosis of malignancy. Lesions of herpes zoster were most frequently found in the thoracic nerve regions. Five of 11 zoster patients with cutaneous dissemination, three of five zoster patients having aseptic meningitis and three of four patients complicated facial palsy were children without underlying disease.

CONCLUSIONS

The present study confirmed that varicella in the first year of life was a risk factor in immunocompetent children, as reported previously. Herpes zoster in children without immunosuppression was found not to be as mild as generally accepted.

Genetic Diversity of Xanthomonas oryzae pv. oryzae Strains from Sri Lanka

ABSTRACT Sixty strains of Xanthomonas oryzae pv. oryzae, collected from 29 locations in Sri Lanka in 1995, were analyzed by restriction fragment length polymorphism using either polymerase chain reaction-amplified 16S and 23S rDNA or the repetitive DNA element IS1112 from X. oryzae pv. oryzae as hybridization probes. Two different ribogroups were observed in the Sri Lankan strains using rDNA probes, whereas five clusters were identified by the IS1112 probe. Bootstrap analysis revealed that the five clusters defined by IS1112 were relatively robust. Our results suggest that the Sri Lankan strains are phylogenetically composed of five different groups. Each cluster was partially associated with climatic conditions (intermediate zone and wet zone) and was related to groups based on ribotyping. Based on virulence analysis using 12 rice cultivars, each containing a single resistance gene, 14 pathotypes were identified among the Sri Lankan strains. All strains were virulent to resistance genes Xa1, Xa2, Xa4, Xa10, Xa11, and Xa14. Only one strain (pathotype 1) was virulent to all major resistance genes including Xa21, while strains of the other pathotypes were all avirulent to Xa21. A partial relationship was found between the determined phylogenetic groups using the IS1112 probe and pathotypes for all but two clusters. The results of this study will facilitate the further understanding of the population structure of X. oryzae pv. oryzae in Sri Lanka.

A lipochito-oligosaccharide, Nod factor, induces transient calcium influx in soybean suspension-cultured cells

Lipochito-oligosaccharides (Nod factors) produced by Rhizobium or Bradyrhizobium are the key signal molecules for eliciting nodulation in their corresponding host legumes. To elucidate the signal transduction events mediated by Nod factors, we investigated the effects of Nod factors on the cytosolic [Ca2+] of protoplasts prepared from roots and suspension-cultured cells of soybean (Glycine max and G. soja) using a fluorescent Ca2+ indicator, Fura-PE3. NodBj-V (C18:1, MeFuc), which is a major component of Nod factors produced by Bradyrhizobium japonicum, induces transient elevation of cytosolic [Ca2+] in the cells of soybean within a few minutes. This effect is specific to soybean cells and was not observed in the tobacco BY-2 cells. Furthermore, NodBj-V without MeFuc did not induce any cytosolic [Ca2+] elevation in soybean cells. Exclusion of Ca2+ from the medium, as well as pre-treatment of the cells with an external Ca2+ chelator or with a plasma membrane voltage-dependent Ca2+ channel inhibitor, suppressed the Nod factor-dependent cytosolic [Ca2+] elevation. These results indicate that transient Ca2+ influx from extracellular fluid is one of the earliest responses of soybean cells to NodBj-V (C18:1, MeFuc) in a host-specific manner.

[A retrospective study of the length of hospitalization following allogeneic bone marrow transplantation]

To estimate the length of hospitalization following bone marrow transplantation(BMT), we conducted a retrospective study of 190 patients who had received allogeneic BMTs at our institution. By our criteria, patients were considered ready for discharge if they were afebrile, did not need intravenous chemotherapy or blood transfusions more than 2 times per week, had maintained these conditions for 1 week or more, and also had no medical history of hepatic veno-occlusive disease, grade-II-or-higher graft-versus-host disease, interstitial pneumonitis, or severe hepato-renal dysfunction. The median length of hospitalization was 108.5 days. Of 82 patients who satisfied our discharge criteria by their 70th hospital day, 10 experienced mild complications during the next 30 hospital days. Of 89 patients who were considered ready for discharge by the 40th hospital day, 30 and 38 experienced complications during the next 30 and 60 hospital days, respectively, and 16 required emergency treatment. No significant baseline characteristics distinguished the patients who experienced complications from those who did not, either after 40 or 70 hospital days. This compounded the difficulty of predicting the development of complications in patients who satisfied our discharge criteria. Although management on an outpatient basis should be safe and feasible for BMT patients who meet our discharge criteria by the 70th day of hospitalization, caution is advised for early discharges after only 40 hospital days.

Enhanced resistance to bacterial diseases of transgenic tobacco plants overexpressing sarcotoxin IA, a bactericidal peptide of insect

Sarcotoxin IA is a bactericidal peptide of 39 amino acids found in the common flesh fly, Sarcophaga peregrina. Many agronomically important bacteria in Japan are killed by this peptide at sub-micro molar levels, and the growth of tobacco and rice suspension cultured cells is not inhibited with less than 25 microM. Transgenic tobacco plants which overexpress the peptide, i.e. over 250 pmol per gram of fresh leaf, under the control of a high expression constitutive promoter showed enhanced resistance to the pathogens for wild fire disease (Pseudomonas syringae pv. tabaci) and bacterial soft rot disease (Erwinia carotovora subsp. carotovora).

Vertical infection of human immunodeficiency virus as an imported infectious disease

BACKGROUND AND METHODS

In Japan, 26 children who vertically acquired human immunodeficiency virus (HIV) infection had been reported as at February 1997. Little information was published about their epidemiological backgrounds and the rate of perinatal HIV transmission in Japan remains unknown. To learn the epidemiological features of perinatal HIV infection in Japan, we examined the medical records of five perinatally infected children.

RESULTS

Three of five mothers were Japanese and two others were South East Asian. Four of them acquired HIV infection abroad and one became infected through her spouse who had acquired infection abroad. Therefore, HIV infection in these five cases can be regarded as an imported infectious disease. None of the five mothers noticed their HIV infection before their pregnancy. One mother was found to be HIV seropositive during her pregnancy, but the others did not notice their HIV infection until their delivery.

CONCLUSIONS

To reduce the incidence of perinatally HIV-infected children it is necessary to lower the incidence of mother-to-infant HIV transmission. In Western countries they have succeeded in reducing the risk for perinatal HIV transmission with perinatal zidovudine therapy. To prescribe the preventive therapy against perinatal HIV transmission, it is essential to know if pregnant women are infected with HIV or not. Therefore, women of childbearing age should accept voluntary prenatal HIV testing. At the same time, they should be offered such programs that can enable them to receive timely counseling, besides medical treatment, if they are found to be HIV infected.

Construction of a BAC library of the rice blast fungus Magnaporthe grisea and finding specific genome regions in which its transposons tend to cluster

We have constructed a BAC library of the rice blast fungus Magnaporthe grisea consisting of 5760 clones. The insert size ranged from 35 to 175 kbp, with an average of 120 kbp. The library is about 18 genomes equivalent, therefore covering more than 99.999% of the genome. This library is the first to be constructed using a rice pathogenic wild type isolate. Improved high molecular weight DNA size fractionating helped to construct the library with high efficiency. Total library clones were arranged onto two nylon membranes for efficient screening. Test hybridization with a single-copy RFLP marker showed ten positive clones, of which restriction patterns indicated no chimerality or deletions. As a model case of application of this library, the distribution of the well-studied fungal retrotransposons MGSR1, MGR583, and MAGGY and DNA transposons MGR586 and Pot2 was analyzed. Of all the BAC clones, 10%, 13%, 18%, 12%, and 23% contained MGSR1, MGR583, MAGGY, MGR586 and Pot2, respectively. The percentage of clones possessing more than five kinds of transposons was 1.4%, 215 times greater than the expected number. The results show that these transposons were distributed in clusters in the M. grisea genome.

[Hemolytic uremic syndrome after bone marrow transplantation]

One hundred and thirteen patients who underwent autologous or allogeneic bone marrow transplantation (BMT) were investigated for the subsequent development of hemolytic uremic syndrome (HUS). HUS developed in seven patients (four males and three females, five acute lymphocytic leukemia (ALL), one acute myelogenous leukemia, one non-Hodgkin's lymphoma) between 36-196 days after BMT. Four patients were recipients of autologous BMT and three were those of allogeneic BMT. Six patients were preconditioned with the regimens including fractionated total body irradiation (TBI). ALL and preconditioning regimen with TBI were suspected to be the risk factors for the development of HUS. Cyclosporin A (CSP) administration was discontinued in three patients who had been given CSP for graft-versus-host disease prophylaxis. Predonisolone was given to the three patients and plasma exchange was performed in one patient. Both hemolytic anemia and thrombocytopenia were resolved in virtually all patients, while creatinine elevation has persisted along with hypertension in one patient.

A cell wall-bound beta-glucosidase from germinated rice: purification and properties

A large portion of beta-glucosidase (EC 3.2.1.21) in germinating rice seeds, which appears to be ionically bound to cell walls, can be solubilized with 1 M NaCl. Its activity increased more than eight-fold within five days of germination. It was purified to electrophoretic homogeneity from the extracts of germinated rice seeds by fractionation with (NH4)2SO4 followed by CM-Sepharose, Polybuffer exchanger 118, Concanavalin A-Sepharose and Bio-Gel P-100. The Mr of the purified enzyme, estimated by SDS-PAGE, was 56,000 and the isoelectric point was > 10.0. Its N-terminal amino acid sequence (44 residues) exhibited high homology to those of beta-glucosidases from other plants, such as barley and white clover. Its activity was optimal at pH 4.5 and 50 degrees, and it was strongly inhibited by glucono-1,5-lactone. The enzyme showed hydrolytic as well as transglycosylation activity towards (1-->3)-beta- and (1-->4)-beta-linked oligosaccharides with degree of polymerization of 2-4. The results suggest that the beta-glucosidase is probably involved not only in hydrolysis but also in modification of oligosaccharides in cell walls of germinating rice seeds.

[Clinical and bacteriological studies on panipenem/betamipron in pediatrics. Kanagawa Research Group for Infectious Diseases of Children]

Following its introduction into the market, PAPM/BP (panipenem/betamipron) was clinically studied in 188 evaluable cases out of 207 cases primarily of respiratory infectious diseases treated at the pediatric departments of 15 hospitals. In the clinical evaluation, the drug proved effective in three of three cases of sepsis; three of three cases of suppurative meningitis; nine of ten cases of laryngopharyngitis, six of seven cases of tonsillitis, 56 of 63 cases of acute bronchitis, 90 of 98 cases of pneumonia, and one of one case of phyothorax, all of which are respiratory infectious diseases; one of one case of secondary infection of a chronic respiratory disease; and two of two cases of lymphadenitis, which is a disease of the soft dermal structure. The overall efficacy rate was 91.0% (171/188 cases). In the bacteriological study, Gram-positive bacteria were eliminated in five of five strains of S. aureus, 30 of 31 strains of S. pneumoniae (96.8%), and three of three strains of S. pyogenes. Gramnegative bacteria were eliminated in 15 of 17 strains of H. influenzae (88.2%), three of four strains of M. catarrhalis, and two of two strains of K. pneumoniae. The overall elimination rate was 92.1% (70/76 strains). In the 23 strains of S. pneumoniae that were examined, penicillin-resistant strains accounted for 56.5%, showing an elimination rate of 100%. No serious adverse effects were observed, and the incidence of adverse effects was 1.45%. As for abnormalities in laboratory tests, levels of GOT and GPT increased in eight cases (3.88%), LDH increased in one case (0.48%), and neutropenia occurred in one case (0.51%). These results suggest that PAMP/BP could be considered the first choice in the treatment of infectious diseases in pediatrics, due to its effectiveness and high level of safety.

Altered calcium handling in compensated hypertrophied rat cardiomyocytes induced by pressure overload

To investigate Ca2+ handling in compensated hypertrophied cardiomyocytes, we measured Ca2+ transients and contraction of hypertrophied rat left ventricular myocytes induced by aortic constriction (AC). The fluorescence ratio (I405/I480) after indo-1/AM loading and circumferential length were simultaneously measured in isolated myocytes. The amplitude of Ca2+ transients (Ca-Amp) was higher in rats with AC than in sham-operated rats (Sham) (0.25 +/- 0.08 vs 0.17 +/- 0.05). There was a positive correlation between Ca-Amp and fractional shortening (FS) in both AC and Sham rats, whereas the ratio of FS/Ca-Amp was smaller in AC rats. These observations suggest that compensated hypertrophied cardiomyocytes exhibit an adaptive increase in Ca-Amp, associated with reduced myofilament responsiveness to an increase in Ca2+. Isoproterenol and forskolin increased Ca-Amp and FS, and decreased time to 50% decline of Ca2+ transients. Although myocytes from AC rats exhibited reduced responsiveness to isoproterenol, responses to forskolin did not differ between the 2 groups. The reduced beta-adrenergic response in Ca2+ handling was probably due to altered beta-adrenoceptor numbers, G-protein function and/or their coupling process.

[Relationship between the presence of side-holes in bone marrow aspiration needle and the number of harvested bone marrow mononuclear cells]

The aim of this study was to evaluate the yield of nucleated cells in bone marrow harvested by means of Downs' Islam aspiration needles with or without side-holes. Twenty marrow donors for HLA identical sibling transplants were studied. Bone marrow nucleated cells were harvested 50 ml in the right iliac bone with a Downs' Islam aspiration needle with or without side-holes and 50 ml in the left with another kind of needle by means of 5 ml aspirations in each donor. There were no significant difference between the number of nucleated cells by means of Downs' Islam aspiration needles with and without side-holes by cross-over analysis. All nucleated cell counts were 33.06 +/- 12.93 x 10(3)/microliter (mean +/- standard deviation) by means of the needle with side-holes and 32.90 +/- 15.25 x 10(3)/microliter by means of the needle without side-holes. The Downs' Islam aspiration needle without side-holes seems to be better in bone marrow harvest from normal volunteers than that with side-holes, because the former may be stronger than the latter.

Elucidation of the mechanism enhancing the avidity of lectin with oligosaccharides on the solid phase surface

The mechanism underlying molecular recognition of lectins was elucidated by a novel solid phase binding assay system based on surface plasmon resonance. When the apparent affinities of interactions between chitooligosaccharides and wheat germ agglutinin were compared between lectin-immobilized and oligosaccharide-immobilized assay systems, the affinity constants (Ka) calculated for the former system were in good agreement with the previously reported values measured in solution. On the other hand, in the latter system, the calculated Ka could be more than 10,000 times higher than the values in solution at lower lectin concentrations. To elucidate the reason for this, we systematically investigated the effects of the oligosaccharide immobilized density and the lectin valence on the apparent affinity in the oligosaccharide-immobilized assay system. Both the apparent association (k[ass]) and dissociation rate constants (k[diss]) showed a tendency to decrease as the oligosaccharide density increased. This effect was most remarkable for the interaction possessing an extremely fast intrinsic k(ass). Oligomerization of lectin enhanced the avidity due to a significant reduction in k(diss). These phenomena could be explained by considering the nonhomogeneous conditions under which binding occurred. The reaction in a nonhomogeneous state is limited by the mass transport effect, and the effect of rebinding becomes so large that it cannot be disregarded. These findings are the first to demonstrate the importance of the mass transport effect in modulating the affinity of lectin for oligosaccharides on a solid phase surface.

Effect of continuous intravenous administration of high-dose G-CSF on hematologic recovery following autologous purged bone marrow transplantation

Delay in peripheral blood recovery is a common complication of autologous purged bone marrow transplantation. To overcome this problem, we examined the effect of continuous intravenous administration of high-dose G-CSF on hematologic recovery following autologous bone marrow transplantation (auto-BMT) with purged bone marrow. Continuous intravenous administration of high dose G-CSF significantly facilitated the recovery of platelet counts and reticulocyte counts compared to one-hour bolus intravenous injection of the usual-dose G-CSF, although both ways of administration facilitated the recovery of leukocyte counts. The results showed continuous intravenous administration of high-dose G-CSF was useful to facilitate the recovery of not only leukocytes but also reticulocytes and platelets following auto-BMT with purged bone marrow in certain situations. Continuous i.v. administration of high-dose G-CSF may be one of the safest and most useful modes facilitating the hematopoietic recovery following auto-BMT with purged bone marrow.

Risk factors for hepatic veno-occlusive disease after bone marrow transplantation: retrospective analysis of 137 cases at a single institution

One hundred and thirty-seven consecutive patients who received bone marrow or peripheral blood stem cell transplantation were studied retrospectively to identify the risk factors for hepatic veno-occlusive disease (VOD). Of the 137 recipients, twenty (14.6%) patients were diagnosed with VOD using the McDonald's criteria. In these 20 patients with VOD, we analyzed various clinical parameters, including age, sex, HLA status, conditioning regimen, irradiation, immunosuppressive agents, mode of transplantation, history of hepatic dysfunction, pre-transplant hepatic and renal function, infectious episodes, antibiotics use, and serum viral titers. A history of hepatic dysfunction and low levels of pseudocholinesterase before transplantation were found to be statistically significant (P = 0.04 and 0.04). Low levels of pseudocholinesterase were significant by multivariate analysis using the logistic regression model (P = 0.02). These results suggest that pseudocholinesterase levels before transplant are important markers of VOD in patients receiving BMT.

Identification of a high-affinity binding protein for N-acetylchitooligosaccharide elicitor in the plasma membrane of suspension-cultured rice cells by affinity labeling

A high-affinity binding protein for the N-acetylchito-oligosaccharide elicitor of phytoalexin biosynthesis was identified by photoaffinity labeling and affinity cross-linking in the plasma membrane of suspension-cultured rice cells. Both a [125I]-labeled photolabile 2-(4-azidophenyl)ethylamino conjugate ([125I]-GN8-AzPEA) and a [125I]-labeled 2-(4-aminophenyl)ethylamino conjugate ([125]-GN8-APEA) of N-acetylchito-octaose were synthesized. The two conjugates were separately incubated with the plasma membrane prepared by aqueous two-phase partitioning, and covalently cross-linked to the elicitor binding site by irradiation with UV light or treatment with the cross-linking agent glutaraldehyde, respectively. Autoradiography of the SDS-PAGE gel of the solubilized membrane proteins revealed the labeling of a single 75 kDa band in both cases. The incorporation of the radiolabeled ligands into the 75 kDa protein showed a saturable mode of binding, with half-maximal incorporation at 45 and 52 nM for photoaffinity labeling and affinity cross-linking, respectively. The labeling of the 75 kDa protein was inhibited by N-acetylchito-oligosaccharides in a size-dependent manner, and N-acetylchito-octaose (GlcNAc)8 showed a half-maximal inhibition at concentrations of the order of 10 nM. However, neither chito-octaose (GlcN)8, cellopentaose nor alpha-1,4 linked N-acetylgalactosamine octamer (GalNAc)8 at concentrations as high as 25 microM inhibited the labeling of the 75 kDa protein. These results are in good agreement with the sensitivity and the specificity of the 'high-affinity binding site' previously identified by binding assays, as well as with the activities of these oligosaccharides in the induction of phytoalexin biosynthesis and other cellular responses. These results suggest that the 75 kDa protein identified by the affinity labeling represents a functional receptor for this elicitor.

Comparison of cytomegalovirus (CMV) antigenemia and CMV in bronchoalveolar lavage fluid for diagnosis of CMV pulmonary infection after bone marrow transplantation

A comparative cytomegalovirus (CMV) diagnostic study was carried out on 30 bone marrow transplant patients. Forty-three bronchoalveolar lavage fluid (BALF) samples from these patients were examined for CMV by viral culture, polymerase chain reaction (PCR), shell vial and cytology. In parallel, peripheral blood samples were subjected to CMV antigenemia assay. CMV was detected in 12 (27.9%) of the 43 BALF samples (10 samples in viral culture, 10 samples in PCR, eight samples in shell vial and three samples in cytology). The CMV antigenemia assay yielded a positive result for six samples. The rates of agreement between results of the CMV antigenemia assay and results of each of the BALF tests were as follows: 81.4% with viral culture, 76.7% with PCR, 86.0% with shell vial, and 88.4% with cytology. Although the sensitivity of the CMV antigenemia assay was inferior to the sensitive tests of BALF samples, statistically significant correlations were demonstrated between the CMV antigenemia assay, viral culture, shell vial and cytology. Although the CMV antigenemia assay was shown to be useful for detection of CMV, it may be necessary to confirm not only the sensitivity but also the specificity of this method for prevention of CMV disease after BMT.

Isolation, cDNA cloning, biological properties, and carbohydrate binding specificity of sieboldin-b, a type II ribosome-inactivating protein from the bark of Japanese elderberry (Sambucus sieboldiana)

A type II ribosome-inactivating protein (RIP) was isolated from the bark tissue of Japanese elderberry (Sambucus sieboldiana) and named sieboldin-b. Sieboldin-b is a heterodimeric protein consisting of 27- and 33-kDa subunits and showed strong ribosome-inactivating activity in vitro but did not show in vivo toxicity. The amino acid sequence of sieboldin-b deduced from the structure of the cDNA showed that both subunits of sieboldin-b are encoded on a single precursor polypeptide. Sieboldin-b has a structure homologous with the Neu5Ac(alpha 2-6)Gal/GalNAc-specific bark lectin from S. sieboldiana (SSA) and also typical type II RIPs such as ricin and abrin. Detailed analyses of carbohydrate binding properties of sieboldin-b revealed that sieboldin-b binds to Gal/GalNAc, similar to ricin/abrin, in spite of its highly homologous structure with SSA. The biological properties of these toxins/lectins are compared, and the possible explanation for such diversity is discussed.

A comparison of young and aged populations for the diphtheria and tetanus antitoxin titers in Japan

The antitoxin levels for diphtheria and tetanus were measured with samples of a young group immunized with diphtheria-tetanus-acellular pertussis combined vaccine and those of an aged group, members of which had not received vaccination in their youth. In the young group members of which had already received basic immunization with diphtheria-tetanus-acellular pertussis combined vaccine, the levels of both antitoxins rose well after injection at 11 to 12 years old with diphtheria-tetanus combined toxoids and remained high until 20 years of age. In the aged group, more than 80% showed antitoxin levels above 0.01 u/ml for diphtheria, while all had levels below that for tetanus, except three persons with confirmed tetanus immunization history. Maintenance of the protective antitoxin levels in the population by vaccination is necessary to prevent outbreaks of infection among unvaccinated or only partially immunized persons.