Rapid weight gain during infancy and early childhood is related to higher anthropometric measurements in preadolescence.

BACKGROUND: This study examined the relationship between rapid weight gain during infancy and/or early childhood and anthropometric measurements [body mass index (BMI), percent body fat (%BF), waist circumference (WC) and waist-to-height ratio (WHtR)] in preadolescence by sex. METHODS: Subjects were fourth-grade school children (aged 9 to 10 years) from elementary schools in Ina-town, Japan, in 2010. Measurements of height, weight, %BF and WC were conducted for each subject. We obtained data on height and weight of subjects at birth, age 1.5 years and age 3 years from the Maternal and Child Health handbook. Rapid weight gain was defined as a change in weight-for-age standard deviation score greater than 0.67 from birth to age 1.5 years (infancy) or from age 1.5 to 3 years (early childhood). RESULTS: All anthropometric variables (BMI, %BF, WC and WHtR) at age 9 to 10 years were significantly higher in the rapid weight gain during both infancy and early childhood period group than in the no rapid weight gain group, regardless of sex. When compared with the no rapid weight gain group, rapid weight gain during early childhood period had significantly higher BMI and WC in boys and BMI, %BF and WC in girls. Compared with the no rapid weight gain group, the rapid weight gain during infancy group had a significantly higher WC in boys and significantly higher BMI and WC in girls. CONCLUSION: Rapid weight gain during both infancy and early childhood was related to higher anthropometric measurements, including WHtR, among Japanese preadolescents, regardless of sex. This study suggests that rapid weight gain during infancy and early childhood may be a risk factor for general/abdominal obesity later in life.

Influence of eating quickly and eating until full on anthropometric gains in girls: A population-based, longitudinal study.

BACKGROUND: In examining childhood overweight/obesity, there is a need to consider both eating quickly and eating until full. This longitudinal study investigated the influence of eating quickly and/or eating until full on anthropometric variables and becoming overweight/obese among Japanese schoolgirls. METHODS: Study participants were fourth-grade schoolgirls (aged 9 or 10 years) in Ina Town, Japan. Physical examinations and a questionnaire survey were performed at baseline (fourth grade) and after 3 years (seventh grade). Height, weight, and waist circumference were measured in the physical examinations, while the data on eating quickly and eating until full were collected in the questionnaire survey. Analysis of variance and analysis of covariance were used to compare the differences in each anthropometric variable between fourth and seventh grade among groups. RESULTS: Data on 425 non-overweight/obese schoolgirls in fourth grade were analyzed. Gains in anthropometric variables (body mass index, waist circumference, and waist-to-height ratio) from fourth to seventh grade were significantly larger in the "eating quickly and eating until full" group than in the "not eating quickly and not eating until full" group. In contrast, there were no significant differences in the gains between the "eating quickly or eating until full" group and the "not eating quickly and not eating until full" group. The proportion of overweight/obese girls in seventh grade was higher in the "eating quickly and eating until full" group than in the other groups. CONCLUSIONS: Eating quickly and eating until full had a substantial impact on excess gains in anthropometric variables among schoolgirls, suggesting that modifying these eating behaviors may help prevent non-overweight/obese girls from the excess gains. Accordingly, school health programs need to focus on not eating quickly and/or not eating until full to prevent overweight/obesity; it is necessary to emphasize "the risk of overweight/obesity associated with these eating behaviors" in schools.

Rapid weight gain during early childhood is associated with overweight in preadolescence: a longitudinal study in Japan.

BACKGROUND: The objective of this study was to examine the relationship between rapid weight gain during early childhood and overweight in preadolescence by sex. METHOD: Study subjects were 676 boys and 620 girls in fourth grade (aged 9 or 10 years) from elementary schools in Ina-town, Japan, during 2010-2012. Height and weight of subjects at birth, age 1.5 and 3 years, were collected from the Maternal and Child Health Handbook, while values at 9-10 years were measured. Rapid weight gain was defined as a change in weight-for-age standard deviation score greater than 0.67 from birth to age 1.5 years (0-1.5 years) or from age 1.5 to 3 years (1.5-3 years). RESULTS: After adjustment for confounding factors, compared with no rapid weight gain, rapid weight gain during 0-1.5 years and 1.5-3 years or rapid weight gain during 1.5-3 years but not during 0-1.5 years significantly increased the odds ratio (OR) for overweight at age 9-10 years in boys (OR, 6.21; 95% confidence interval [CI], 2.84-13.58 and OR, 3.31; 95% CI, 1.67-6.54, respectively) and girls (OR, 7.55; 95% CI, 2.99-19.07 and OR, 3.42; 95% CI, 1.38-8.49, respectively). CONCLUSION: The present study suggests that rapid weight gain during early childhood was associated with being overweight in preadolescence, regardless of sex.

Modification of the analysis of parathyroid hormone-related protein in milk and concentrations of this protein in commercial milk and milk products in Japan.

Parathyroid hormone-related protein (PTHrP), which causes hypercalcemia associated with malignant tumors, is known to be present in milk. Gene expression of PTHrP in the mammary gland increases markedly during parturition and with the onset of lactation. Even when circulating PTHrP levels are extremely low or below the detection limit, milk PTHrP levels are remarkably high. Parathyroid hormone-related protein derived from the mammary gland is assumed to play a role in maintaining the maternal calcium homeostasis and calcium transport from blood to milk. In previous studies that determined the PTHrP concentrations in milk, the pretreatments and diluent composition were not standardized. Here, we investigated the effect of various pretreatment procedures and diluent constitutions and the consequent PTHrP concentrations in commercial milk and milk products in Japan. Significant differences were found in PTHrP concentrations in raw milk samples subjected to different combinations of pretreatments (mixing, centrifugation, acidification, and heating) and diluents (0pM standard solution of PTHrP, plasma treated with protease inhibitors, and original diluent). We measured the PTHrP concentrations in normal liquid milk, processed milk, milk drinks, formulated milk powders, and skim milk powder by using the appropriate combination of pretreatment (acidification) and diluent (plasma treated with protease inhibitors). The PTHrP concentration in normal liquid milk, processed milk, and skim milk powder was as high as that in raw milk (>5nM), whereas that in milk drinks differed considerably. The PTHrP concentration in infant formulas (<2nM) was lower than that in the other milk products. These results indicate that a certain amount of PTHrP is ingested when milk and milk products are consumed.

An African pygmy hedgehog adenovirus 1 (AhAdV-1) outbreak in an African pygmy hedgehog (Atelerix albiventris) colony in Japan.

An African pygmy hedgehog adenovirus 1 (AhAdV-1) outbreak in a colony of 24 African pygmy hedgehogs (APHs) with a case of fatal pneumonia occurred in Japan. Thirteen out of a colony of 15 APHs with respiratory symptoms were diagnosed with AhAdV-1 infection based on the detection of AhAdV-1 genome in throat/nasal swabs and further one APH was diagnosed on isolation of the virus. Five infected APHs died during the outbreak and AhAdV-1 caused severe pneumonia and death in one case. After the outbreak, persistent AhAdV-1 infection was suggested in one surviving APH. AhAdV-1 is a novel adenovirus and is suspected to be an emerging pathogen.

Inhibitory effect of cinnamaldehyde, derived from Cinnamomi cortex, on the growth of influenza A/PR/8 virus in vitro and in vivo.

We have investigated the inhibitory effect of trans-cinnamaldehyde (CA), one of the principal constituents of essential oil derived from Cinnamomi cortex, on the growth of influenza A/PR/8 virus in vitro and in vivo. When 1-h drug treatment was initiated at various times post-infection (p.i.) in Madin-Darby canine kidney cells using a fixed dose of CA (40 microM), the maximum inhibitory effect (29.7% virus yield of control) was obtained when drug treatment was started at 3h p.i. Under the same treatment schedule, CA inhibited the virus growth in a dose-dependent manner (20-200 microM), and, at 200 microM, the virus yield was reduced to an undetectable level. RT-PCR and SDS-PAGE analyses showed that CA inhibited viral protein synthesis at the post-transcriptional level. In mice infected with the lung-adapted PR-8 virus, inhalation (50mg/cage/day) and nasal inoculation (250 microg/mouse/day) of CA significantly increased survival rates on the 8 days to 100% and 70%, respectively, in contrast to a survival rate of 20% in the untreated control group. Importantly, inhalation of CA caused virus yield reduction by 1 log in bronchoalveolar lavage fluid on day 6 after infection, compared with that of the untreated control group. These findings might provide further support to the empirical indication of Cinnamomi cortex-containing Kampo medicines for acute respiratory infectious diseases.

Analysis of individual differences in radiosensitivity using genome editing.

Current standards for radiological protection of the public have been uniformly established. However, individual differences in radiosensitivity are suggested to exist in human populations, which could be caused by nucleotide variants of DNA repair genes. In order to verify if such genetic variants are responsible for individual differences in radiosensitivity, they could be introduced into cultured human cells for evaluation. This strategy would make it possible to analyse the effect of candidate nucleotide variants on individual radiosensitivity, independent of the diverse genetic background. However, efficient gene targeting in cultured human cells is difficult due to the low frequency of homologous recombination (HR) repair. The development of artificial nucleases has enabled efficient HR-mediated genome editing to be performed in cultured human cells. A novel genome editing strategy, 'transcription activator-like effector nuclease (TALEN)-mediated two-step single base pair editing', has been developed, and this was used to introduce a nucleotide variant associated with a chromosomal instability syndrome bi-allelically into cultured human cells to demonstrate that it is the causative mutation. It is proposed that this editing technique will be useful to investigate individual radiosensitivity.

Macrophage recognition of the erythrocytes modified by oxidizing agents.

Mouse erythrocytes modified by oxidizing agents (ADP/Fe3+, tert-butyl hydroperoxide and phenylhydrazine) were examined for recognition by autologous macrophages (cell adhesion and phagocytosis). Treatment of erythrocytes with ADP/Fe3+ resulted in lipid oxidation but no significant alterations in physical properties, and the treated cells were adherent to macrophages. When the lipid oxidation of erythrocytes was prevented by alpha-tocopherol, erythrocytes were not susceptible to macrophage adhesion, indicating that free radical reactions involving lipid oxidation are responsible for the formation or exposure of the membrane sites for the macrophage adhesion. Treatment of erythrocytes with tert-butyl hydroperoxide caused lipid oxidation and alterations in physical properties. Deformability and osmotic fragility of the treated cells were markedly low. Not only cell adhesion but subsequent phagocytosis of the treated cells by macrophages were observed. A similar effect was observed on treatment of erythrocytes with phenylhydrazine. The pronounced alterations in physical properties of the erythrocytes treated with tert-butyl hydroperoxide and phenylhydrazine may be responsible for the macrophage phagocytosis.

Macrophage recognition of periodate-treated erythrocytes: involvement of disulfide formation of the erythrocyte membrane proteins.

Upon exposure to 2 mM periodate at 0 degrees C for 15 min, mouse erythrocytes underwent membrane lipid oxidation, oxidation of cell surface sialyl residues into aldehyde-bearing derivatives, and oxidation of SH groups of the membrane proteins into disulfides. The periodate-treated erythrocytes exhibited a remarkable increase in rosette attachment to resident mouse peritoneal macrophages in the absence of serum. The relationship between the oxidation of the membrane constituents and the macrophage recognition of these cells was investigated. Periodate treatment of erythrocytes in the presence of butylated hydroxytoluene, an inhibitor of lipid oxidation, did not affect the subsequent attachment of the erythrocytes to the macrophages. Reduction of the periodate-treated erythrocytes with borohydride or cyanoborohydride did not affect the erythrocyte attachment. Neuraminidase treatment of erythrocytes before periodate did not affect the attachment either. On reduction of the disulfides of the membrane proteins with dithiothreitol, the periodate-treated erythrocytes lost their ability to attach to the macrophages. Erythrocytes treated with an SH-oxidizing agent, diamide, were then examined for the macrophage recognition. The diamide-treated cells also showed rosette attachment to the macrophages in the absence of serum, but did not when reduced with dithiothreitol. These results indicate that oxidation of the SH groups of the membrane proteins to disulfides causes reversible membrane changes that macrophages recognize, and it is this mechanism that is responsible for the macrophage recognition of the periodate-treated erythrocytes.

Molecular cloning and expression of aquaporin 1 [correction of aquapolin 1] (AQP1) in dog kidney and erythroblasts.

Complementary DNA of the water channel aquaporin 1 (AQP1) was cloned from dog kidney and erythroblasts. The cDNA amplified from mRNA in dog kidney was 816 bp, the same as that in bovines, but longer by 6 bp than that in humans, mice and rats. The 235-bp fragment cDNA amplified from the mRNA in dog erythroblasts, which was differentiated from peripheral blood, was completely identical to the corresponding sequence of cDNA from the dog kidney. Thus, mature red blood cells from dog may have AQP1 in their cell membranes. The amino acid sequence in dog AQP1 was 91-94% identical to that in the other species mentioned above. Dog AQP1 has six predicted transmembrane domains, two NPA motifs, one mercury-sensitive site and four consensus phosphorylation sites, the same as the other species. However, dog and bovine AQP1 have only one N-glycosylation site, while two glycosylation sites were found in human and rodent AQP1. Xenopus oocytes injected with the mRNA of the dog AQP1 exhibited high water permeability in a hyposmotic medium. Thus, dog AQP1 performs water transport the same as in the other species.

Na-dependent glutamate transport in high K and high glutathione (HK/HG) and high K and low glutathione (HK/LG) dog red blood cells.

Na-dependent glutamate (Glu) influxes in the red blood cells of normal low K (LK), high K and high glutathione (HK/HG), and high K and low glutathione (HK/LG) dogs were compared. The ranges of the influxes in LK, HK/HG and HK/LG cells were 1.0-63, 62-174 and 1.3-26 mumol/1 cells per h, respectively. Some LK and HK/LG dogs had red blood cells with extremely low Glu influxes. In cells with extremely low Glu influxes, however, there were clear Na-dependent Glu influxes. In LK, HK/HG and HK/LG cells, the Km of Na-dependent Glu influx with respect to the medium Glu concentration were 17, 20 and 19 mM, respectively, and the half-maximal activation (K1/2) with respect to medium Na concentration was 39, 40 and 42 microM, respectively. By the addition of harmaline, a hallucinogenic alkaloid, the Vmax in LK cells was not affected and the Km was increased, while the Vmax was decreased and the Km increased in HK/HG and HK/LG cells. The Ki value with harmaline by means of Dixon plot in LK cells was 5.2 mM, against 1.8 and 1.9 mM in HK/HG and HK/LG cells, respectively. These results suggest that the difference in the Na-dependent Glu influxes between 2 HK groups was due to the varying quantity, not the quality, of the transporter.

Preparation and properties of the water-soluble chlorophyll-bovine serum albumin complexes.

By mixing chlorophyll (Chl) a or b with a dense bovine serum albumin solution, the water-soluble Chl-bovine serum albumin complexes were prepared. These complexes, eluted near the void volume on a gel filtration, were separated well from unreacted bovine serum albumin, indicating an aggregation of such molecules in the complexes. Preparation of chlorophyllide (Chlide) a- or Chlide b-bovine serum albumin complex was unsuccessful, while the phytol-, and beta-carotene-bovine serum albumin complexes could be obtained. Chls in the Chl-bovine serum albumin complexes had the following characteristics. Main absorption peak of Chl a or b in the red region occurred at 675 nm or 652 nm, respectively. The Chl a-bovine serum albumin complex having absorption peak at 740 nm was also prepared. As compared with the stabilities of Chl a and b in Triton X-100. Both Chls in the bovine serum albumin-complexes were stable against oxidative stresses, such as photobleaching, Fenton reagent, peroxidase-H2O2 system. But they were easily hydrolyzed by chlorophyllase. These properties of Chls in the bovine serum albumin-complexes were similar to those of Chls in the isolated light-harvesting Chl a/b protein complex. A possible localization of Chls within the bovine serum albumin complexes was suggested that the porphyrin moiety of Chl was buried in bovine serum albumin; however, the hydrophilic edge of porphyrin ring, adjacent to the phytol group, occurred in the hydrophilic region of a bovine serum albumin molecule.

Promoter analysis of the membrane protein gp64 gene of the cellular slime mold Polysphondylium pallidum.

We cloned a genomic fragment of the membrane protein gp64 gene of the cellular slime mold Polysphondylium pallidum by inverse PCR. Primer extension analysis identified a major transcription start site 65 bp upstream of the translation start codon. The promoter region of the gp64 gene contains sequences homologous to a TATA box at position -47 to -37 and to an initiator (Inr, PyPyCAPyPyPyPy) at position -3 to +5 from the transcription start site. Successively truncated segments of the promoter were tested for their ability to drive expression of the beta-galactosidase reporter gene in transformed cells; also the difference in activity between growth conditions was compared. The results indicated that there are two positive vegetative regulatory elements extending between -187 and -62 bp from the transcription start site of the gp64 promoter; also their activity was two to three times higher in the cells grown with bacteria in shaken suspension than in the cells grown in an axenic medium.

FebA: a gene for eukaryotic translation initiation factor 4E-binding protein (4E-BP) in Dictyostelium discoideum.

We have identified a gene encoding a eukaryotic initiation factor 4E-binding protein (4E-BP) in the EST database of the Dictyostelium cDNA project. The Dictyostelium 4E-BP, designated febA (four e-binding), showed significant similarity to mammalian 4E-BPs. Northern blot analysis revealed that febA was expressed at a high level in the vegetative growth phase but the level of expression decreased during late development. The gene was shown to be non-essential since disruption of the gene had no severe effect; the null mutant proliferated normally and formed normal fruiting bodies. However, strains overexpressing the gene could not be established, suggesting that an excess of FebA protein may have a lethal effect on the cells.

Immunoglobulin treatment ameliorates murine myocarditis associated with reduction of neurohumoral activity and improvement of extracellular matrix change.

OBJECTIVES: We examined effects of immunoglobulin on murine myocarditis induced by encephalomyocarditis virus, not pathogenic to humans, and analyzed the plasma cytokine and catecholamine levels and the changes of the extracellular matrix with or without the treatment. BACKGROUND: We have previously shown that immunoglobulin therapy suppressed murine coxsackievirus B3 myocarditis by an antiviral effect. However, it is not yet determined whether beneficial effects of immunoglobulin for myocarditis are due to antiviral effects or to other unknown effects. METHODS: Antiviral activity of human immunoglobulin (Polyglobin-N) against encephalomyocarditis virus was determined in vitro. Immunoglobulin (1 g/kg/day) was administered intraperitoneally to the virus-infected mice daily for two weeks, beginning simultaneously with virus inoculation in experiment I and on day 14 after virus inoculation in experiment II. RESULTS: Antiviral activity of immunoglobulin could not be detected in the assay of a plaque-reduction method in vitro. The in vivo study showed that immunoglobulin administration ameliorated both myocardial necrosis with interstitial fibrin deposition in experiment I and interstitial fibrosis with the improvement of ventricular remodeling in experiment II by the reduction of plasma catecholamines, interferon-alpha, and soluble intercellular adhesion molecule-1. CONCLUSIONS: Immunoglobulin therapy could suppress myocarditis associated with the improvement of extracellular matrix changes by the reduction of neurohumoral activity.

Nitric oxide and murine coxsackievirus B3 myocarditis: aggravation of myocarditis by inhibition of nitric oxide synthase.

OBJECTIVES: This study sought to investigate the effects of nitric oxide inhibition in a murine model of coxsackievirus B3 myocarditis. BACKGROUND: Little is known about the contribution of nitric oxide to the pathophysiology of myocarditis. METHODS: Antiviral activity was tested in vitro using nitric oxide inhibition by treatment with activated macrophages of NG-nitro-L-arginine methyl ester. In the in vivo experiments, NG-nitro-L-arginine methyl ester and NG-nitro-D-arginine methyl ester (both at 100 micrograms/ml) were administered to C3H/He mice early (days 0 to 14) and late (days 14 to 35) after infection with coxsackievirus B3. RESULTS: In the in vitro experiments with interferon-gamma- and lipopolysaccharide-induced activated murine macrophages, treatment with the nitric oxide synthase inhibitor NG-nitro-L-arginine methyl ester, but not its inactive enantiomer NG-nitro-D-arginine methyl ester, restored coxsackievirus B3 titers. In the in vivo experiments in the early treatment group, myocardial virus titers were higher in NG-nitro-L-arginine methyl ester-treated than infected untreated animals, and both inflammatory cell infiltration and necrosis were more severe. In the late treatment group, more severe necrosis and more dense myocardial and perivascular fibrosis were observed in NG-nitro-L-arginine methyl ester-treated than in infected untreated animals. NG-Nitro-D-arginine methyl ester administration was ineffective. CONCLUSIONS: Nitric oxide inhibition increases myocardial virus titers, resulting in the aggravation of cardiac pathology in the early stage of coxsackievirus B3 myocarditis. In the late stage, it induces more severe cardiomyopathic lesions. Nitric oxide plays a defensive role in the pathogenesis of coxsackievirus B3 myocarditis.

Coronary artery spasm immediately after percutaneous transluminal coronary recanalization.

A 55-year-old man developed acute inferior myocardial infarction. A coronary arteriogram performed within two hours later showed complete occlusion of the right coronary artery, which was not resolved by two doses of 300 micrograms of intracoronary nitroglycerin. It was recanalized with 50% luminal diameter narrowing after 600,000 units of urokinase. Immediately after this thrombolytic therapy, the patient experienced chest pain, and the coronary artery became completely obstructed again. The pain was promptly relieved by 300 micrograms of intracoronary nitroglycerin, with disappearance of the obstruction. The observations during the procedure indicate that coronary artery spasm can occur after successful thrombolytic therapy on an occluded artery, inducing postinfarction angina, and might culminate in a second complete occlusion after percutaneous transluminal coronary recanalization.

Effects of polyethylene glycol conjugated superoxide dismutase on coxsackievirus B3 myocarditis in mice.

OBJECTIVE: The aim was to examine the role of oxygen derived free radicals in the development of myocarditis by investigating the effects of polyethylene glycol conjugated superoxide dismutase (PEG-SOD), a potent scavenger of oxygen free radicals, upon coxsackievirus B3 (CB3) myocarditis. METHODS: Two week old male C3H/He mice were inoculated intraperitoneally with 10(3) plaque forming units of CB3. PEG-SOD, 1 x 10(3), 5 x 10(3), 1 x 10(4), and 1 x 10(5) U.kg-1 x d-1, was given subcutaneously daily on days 0 to 14. Treated groups were compared to the infected control. RESULTS: The survival rate of the 1 x 10(5) U.kg-1 x d-1 PEG-SOD group was lower than that of the infected control group (40% v 78%, p < 0.01). The survival rates of the other treated groups did not differ significantly from the infected control. The myocardial calcification score in the 1 x 10(5) U.kg-1 x d-1 PEG-SOD group was higher than in the infected control group on d 7, when myocardial virus titres did not differ significantly among the five groups. The scores for myocardial cellular infiltration and myocardial necrosis in the 1 x 10(3) and the 5 x 10(3) U.kg-1 x d-1 PEG-SOD groups were significantly lower than in the infected control on d 14, when myocardial viruses were not detected in the five groups. However, the myocardial necrosis and myocardial calcification scores in the 1 x 10(5) U.kg-1 x d-1 PEG-SOD group were higher than in the infected control. CONCLUSIONS: The improvement of cardiac pathology in the 1 x 10(3) and the 5 x 10(3) U.kg-1 x d-1 PEG-SOD groups seems to have resulted not from the reduction in myocardial virus titres but from inhibition of generation of oxygen free radicals. The mechanism of the impaired survival and aggravation of cardiac pathology in the 1 x 10(5) U.kg-1 x d-1 PEG-SOD group is unknown. The results suggest that oxygen free radicals may be involved in the pathogenesis and development of CB3 myocarditis and that appropriate dosages of PEG-SOD have therapeutic potential for clinical CB3 myocarditis, although caution must be paid to the treatment window.

Role of oxygen derived free radicals in the pathogenesis of coxsackievirus B3 myocarditis in mice.

OBJECTIVE: The aim was to test the role of oxygen derived free radicals in the development of myocarditis. This involved investigating the effects of polyethylene glycol conjugated superoxide dismutase (PEG-SOD, an enzyme catalysing the conversion of O2.- to H2O2) and polyethylene glycol conjugated catalase (PEG-catalase, accelerating the reaction of H2O2 to H2O and O2) upon coxsackievirus B3 (CB3) myocarditis. METHODS: Two week old male C3H/He mice were inoculated intraperitoneally with 10(3) plaque forming units of CB3. PEG-SOD, 1 x 10(3) U.kg-1 x d-1, and PEG-SOD, 1 x 10(3) U.kg-1 x d-1, plus PEG-catalase, 1 x 10(3) U.kg-1 x d-1, were injected subcutaneously daily on days 0 to 14. Treated groups were compared to the infected control. RESULTS: On day 7, there were no significant differences in pathological scores among the three groups. On day 14, the cellular infiltration, myocardial necrosis, and calcification scores were significantly lower in the PEG-SOD group and the PEG-SOD plus PEG-catalase group than in the control. There were no significant differences in pathological scores between the PEG-SOD group and the PEG-SOD plus PEG-catalase group. There were no differences in the myocardial virus titres on day 7 among the three groups. On day 14, virus was not detected from the myocardium in any of the three groups. CONCLUSIONS: The results suggest that superoxide anion is mostly responsible for myocyte injury in CB3 myocarditis in mice, and that hydrogen peroxide formed as a result of dismutation of superoxide anion may not play a significant role in the development of myocarditis. Superoxide anion is one of the most important factors in free radical mediated injury in CB3 myocarditis in mice and the administration of PEG-SOD alone has therapeutic potential in clinical CB3 myocarditis.

Enhancement of coxsackievirus B3 myocarditis in mice by lobenzarit disodium through inhibition of splenic pan T cells.

OBJECTIVE: The aim was to test the efficacy of the immune system modulator lobenzarit disodium in the treatment of coxsackievirus B3 myocarditis. METHODS: Two week old C3H/He mice were inoculated with 10(3) plaque forming units of coxsackievirus B3. Lobenzarit disodium, 25 mg.kg-1.d-1, was given subcutaneously daily on days 0-14 (experiment I; group 2) and days 14-28 (experiment II; group 4). Both treated groups were compared to infected controls for each experiment (groups 1 and 3). For the analysis of splenic lymphocyte subsets, additional mice in untreated and treated groups were killed on d 7, and the percentages of Thy 1.2 (CD3), L3T4 (CD4), Ly 2 (CD8) subsets were analysed by laser flow cytometry (experiment III). RESULTS: In experiment I, the survival rate in the lobenzarit treated group was significantly lower than in the controls (2/11 v 8/11). Cellular infiltration and myocardial necrosis in the lobenzarit group were more severe. Myocardial virus titres and serum neutralising antibody titres did not differ significantly between the two groups. In experiment II, the survival rate (7/9 v 13/13) and cardiac pathology between the two groups did not differ significantly. In experiment III, the percentage of the Thy 1.2 subset (CD3) in the treated group was significantly lower (p < 0.05) than in the control group, at 36.0(SD 2.9)% v 42.8(5.8)%. CONCLUSIONS: Lobenzarit disodium decreased splenic pan T cells and aggravated both clinical course and cardiac pathology in acute murine coxsackievirus B3 myocarditis.