[Preparation and in vitro evaluation of brucine-loaded polylacticacid nanoparticles]

OBJECTIVE

To prepare and evaluate brucine-loaded polylacticacid nanoparticles (Bru-PLA-NPs).

METHOD

The Bru-PLA-NPs were prepared by solvent diffusion method. The physical, chemical properties and in vitro release behavior of the prepared Bru-PLA-NPs were evaluated, respectively.

RESULT

The mean particle size of the prepared Bru-PLA-NPs was 95 nm with polydispersity index of 0.362. The zeta potential was -15.68 mV. The mean loading and entrapment efficiency of Bru were 7% and 37%, respectively. Compared with Bru solution, an obvious sustained release behavior of Bru from Bru-PLA-NPs was observed in the in vitro release experiment.

CONCLUSION

The Bru-PLA-NPs prepared by solvent diffusion method exhibit small particle size, high Bru-loading efficiency, and obvious sustained release in vitro

Novel polymeric nanoparticles containing tanshinone IIA for the treatment of hepatoma

Novel polylactic acid nanoparticles containing tanshinone IIA (TS-PLA-NPs) were synthesized by a single oil-in-water emulsion/solvent evaporation method. In this study, the optimized nanoparticles were characterized for morphology, mean particle size, zeta potential, entrapment efficiency, drug-loading content, X-ray diffractometer measurement, and in vitro release. The obtained nanoparticles were spherical and intact. The mean particle size was 192.5 nm with polydispersity index being 0.029 and zeta potential - 26.27 mV. The mean entrapment efficiency and loading of tanshinone IIA (TSIIA) in TS-PLA-NPs were 86.35 and 1.61%, respectively. The in vitro release study was performed at pH 7.4 using a dialysis membrane. Without initial burst effect, the TSIIA sustained release from TS-PLA-NPs for more than 7 days. The mean in vitro cumulative release percentage of TSIIA from TS-PLA-NPs vs. time curve fitted well with the Higuchi Equation (Q = 2.0365 + 13.564 x t(1/2), r = 0.9950). In pharmacokinetics and tissue distribution studies, the concentrations of TSIIA are higher in hepatoma and lower in blood, heart, kidney, spleen, and lung at 2 h after TS-PLA-NPs was administered via caudal vein. TS-PLA-NPs were effective in destroying the human liver cancer cells by the Mono-nuclear cell direct cytotoxicity assay (MTT) assay, and the growth-inhibitory effect of TS-PLA-NPs on human liver cancer cells was concentration and time dependent. The effect of TS-PLA-NPs on hepatoma in mice was also performed. The results of TS-PLA-NPs were markedly more effective than both of TSIIA and blank PLA nanoparticles in preventing tumor growth and increasing survival time of mice with hepatoma. This study provided support for the new paradigm, the application of TSIIA for the treatment of hepatoma.

[Study on stability of oridonin solution]

OBJECTIVE

To investigate the stability of oridonin (ORI) solution for research and development of novel ORI prepartions.

METHOD

The effect of pH on the degradation rate of ORI was evaluated, the pH values of the oridonin solutions were adjusted to the setting pH, with 1 mol x L(-1) HCl or NaOH, respectively, and stored at room temperature for 60 h. The constant temperature method was applied to evaluate the stability of ORI solution at room temperature and at 4 degrees C.

RESULT

The pH-rate profile of ORI was V-shaped, and the pHm was 5. The t90 of ORI solution at room temperature was 53.2 h and 91.5 h at 4 degrees C CONCLUSION: The ORI solution is not stable. The pH-dependent degradation of ORI solution confirms to specific acid-base catalysis reaction.

Optimization and in situ intestinal absorption of self-microemulsifying drug delivery system of oridonin

The objective of this study was to optimize and characterize an oridonin self-microemulsifying drug delivery system (SMEDDS) formulation. A central composite design (CCD) was used to investigate the influence of factors (oil percentage and surfactant to co-surfactant ratio (Sur/Co-s ratio)) on the responses including droplet size, polydispersity, equilibrium solubility and in situ intestine absorption rate. Furthermore, the desirability function approach was applied to obtain the best compromise among the multiple responses. It was found that oil percentage played a significant role on the droplet size and polydispersity. The drug equilibrium solubility was mainly contributed to oil percentage and less to Sur/Co-s ratio. The in situ intestinal absorption was influenced by both of the two factors, whereas the oil percentage played a more important role in absorption. The practical response values under the optimized formulation were in good accordance with the predicted values. Our results demonstrate CCD is of value in optimizing the SMEDDS formulation and understanding the effects of formulation compositions on SMEDDS properties.

Role of interferon in homologous and heterologous rotavirus infection in the intestines and extraintestinal organs of suckling mice

Recent studies demonstrated that viremia and extraintestinal rotavirus infection are common in acutely infected humans and animals, while systemic diseases appear to be rare. Intraperitoneal infection of newborn mice with rhesus rotavirus (RRV) results in biliary atresia (BA), and this condition is influenced by the host interferon response. We studied orally inoculated 5-day-old suckling mice that were deficient in interferon (IFN) signaling to evaluate the role of interferon on the outcome of local and systemic infection after enteric inoculation. We found that systemic replication of RRV, but not murine rotavirus strain EC, was greatly enhanced in IFN-alpha/beta and IFN-gamma receptor double-knockout (KO) or STAT1 KO mice but not in mice deficient in B- or T-cell immunity. The enhanced replication of RRV was associated with a lethal hepatitis, pancreatitis, and BA, while no systemic disease was observed in strain EC-infected interferon-deficient mice. In IFN-alpha/beta receptor KO mice the extraintestinal infection and systemic disease were only moderately increased, while RRV infection was not augmented and systemic disease was not present in IFN-gamma receptor KO mice. The increase of systemic infection in IFN-deficient mice was also observed during simian strain SA11 infection but not following bovine NCDV, porcine OSU, or murine strain EW infection. Our data indicate that the requirements for the interferon system to inhibit intestinal and extraintestinal viral replication in suckling mice vary among different heterologous and homologous rotavirus strains, and this variation is associated with lethal systemic disease.

Cholinergic neurons of mouse intrinsic cardiac ganglia contain noradrenergic enzymes, norepinephrine transporters, and the neurotrophin receptors tropomyosin-related kinase A and p75

Half of the cholinergic neurons of human and primate intrinsic cardiac ganglia (ICG) have a dual cholinergic/noradrenergic phenotype. Likewise, a large subpopulation of cholinergic neurons of the mouse heart expresses enzymes needed for synthesis of norepinephrine (NE), but they lack the vesicular monoamine transporter type 2 (VMAT2) required for catecholamine storage. In the present study, we determined the full scope of noradrenergic properties (i.e. synthetic enzymes and transporters) expressed by cholinergic neurons of mouse ICG, estimated the relative abundance of neurons expressing different elements of the noradrenergic phenotype, and evaluated the colocalization of cholinergic and noradrenergic markers in atrial nerve fibers. Stellate ganglia were used as a positive control for noradrenergic markers. Using fluorescence immunohistochemistry and confocal microscopy, we found that about 30% of cholinergic cell bodies contained tyrosine hydroxylase (TH), including the activated form that is phosphorylated at Ser-40 (pSer40 TH). Dopamine beta-hydroxylase (DBH) and norepinephrine transporter (NET) were present in all cholinergic somata, indicating a wider capability for dopamine metabolism and catecholamine uptake. Yet, cholinergic somata lacked VMAT2, precluding the potential for NE storage and vesicular release. In contrast to cholinergic somata, cardiac nerve fibers rarely showed colocalization of cholinergic and noradrenergic markers. Instead, these labels were closely apposed but clearly distinct from each other. Since cholinergic somata expressed several noradrenergic proteins, we questioned whether these neurons might also contain trophic factor receptors typical of noradrenergic neurons. Indeed, we found that all cholinergic cell bodies of mouse ICG, like noradrenergic cell bodies of the stellate ganglia, contained both tropomyosin-related kinase A (TrkA) and p75 neurotrophin receptors. Collectively, these findings demonstrate that mouse intrinsic cardiac neurons (ICNs), like those of humans, have a complex neurochemical phenotype that goes beyond the classical view of cardiac parasympathetic neurons. They also suggest that neurotrophins and local NE synthesis might have important effects on neurons of the mouse ICG.

Extraintestinal spread and replication of a homologous EC rotavirus strain and a heterologous rhesus rotavirus in BALB/c mice

Although rotavirus infection has generally been felt to be restricted to the gastrointestinal tract, over the last two decades there have been sporadic reports of children with acute or fatal cases of rotavirus gastroenteritis testing positive for rotavirus antigen and/or nucleic acid in various extraintestinal locations such as serum, liver, kidney, bladder, testes, nasal secretions, cerebrospinal fluid, and the central nervous system. Recently, studies in animals and people have demonstrated that rotavirus antigenemia is a common event during natural infection. In this study, we extend these observations and compare the intestinal and extraintestinal spread of wild-type homologous murine rotavirus EC and a heterologous strain, rhesus rotavirus (RRV), in newborn mice. A strand-specific quantitative reverse transcription-PCR (ssQRT-PCR) assay was used to quantify the ability of different rotavirus strains to spread and replicate extraintestinally. Both strain EC and RRV were detected extraintestinally in the mesenteric lymph nodes (MLN), livers, lungs, blood, and kidneys. Extraintestinal replication, as measured by ssQRT-PCR, was most prominent in the MLN and occurred to a lesser degree in the livers, kidneys, and lungs. In the MLN, strain EC and RRV had similar (P < 0.05) RNA copy numbers, although EC was present at a 10,000-fold excess over RRV in the small intestine. Rotavirus nonstructural protein 4 (NSP4) and/or assembled triple-layered particles, indicated by immunostaining with the VP7 conformation-dependent monoclonal antibody 159, were detected in the MLN, lungs, and livers of EC- and RRV-inoculated mice, confirming the ssQRT-PCR findings. Infectious RRV was detected in the MLN in quantities exceeding the amount present in the small intestines or blood. The cells in the MLN that supported rotavirus replication included dendritic cells and potentially B cells and macrophages. These data indicate that extraintestinal spread and replication occurs commonly during homologous and some heterologous rotaviral infections; that the substantial host range restrictions for rhesus rotavirus, a heterologous strain present in the intestine, are not necessarily apparent at systemic sites; that the level and location of extraintestinal replication varies between strains; that replication can occur in several leukocytes subsets; and that extraintestinal replication is likely a part of the normal pathogenic sequence of homologous rotavirus infection.

Pharmacokinetic comparisons of Shuang-Huang-Lian with the different combinations of its constitutional herbs

Shuang-Huang-Lian (SHL) is a traditional Chinese formula containing Lonicerae japonicae flos (LJF), Scutellariae radix (SR) and Forsythiae fructus (FF), and is commonly used to treat acute upper respiratory tract infection, acute bronchitis and light pneumonia. The aim of this study is to compare the pharmacokinetics of SHL and the different combinations of its constitutional herbs, and to investigate the influence of compatibility on the pharmacokinetics of the main active ingredient baicalein. Male Sprague-Dawley rats were randomly assigned to four groups and orally administered with SHL, SR, SR+FF and SR+LJF, respectively. At different time points (0, 0.167, 0.333, 0.5, 0.75, 1, 3, 5, 8, 12, 18, 24, 36, 48, 72 h) after administration, the concentrations of baicalein in rat serum were determined by using HPLC, and main pharmacokinetic parameters were estimated. It was found that there were significant differences (p < 0.05) in the parameters, t(1/2) (beta) and C(max) among different combinations of herbs. The results indicate that SHL has delayed the elimination and reduced the bioavailability of baicalein in rat serum.

Corticotropin-releasing factor in the dorsal raphe elicits temporally distinct serotonergic responses in the limbic system in relation to fear behavior

The neurotransmitters serotonin and corticotrophin-releasing factor are thought to play an important role in fear and anxiety behaviors. This study aimed to determine the relationship between corticotrophin-releasing factor-evoked changes in serotonin levels within discrete regions of the limbic system and the expression of fear behavior in rats. The effects of corticotrophin-releasing factor administration to the serotonin cell body regions of the dorsal raphe nucleus on fear behavior, behavioral activity, and extracellular serotonin levels were assessed in freely moving rats with microdialysis probes implanted into the central nucleus of the amygdala and the medial prefrontal cortex. Infusion of corticotrophin-releasing factor (0.5 microg) into the dorsal raphe rapidly induced freezing behavior, which was positively correlated with an immediate increase in serotonin release in the central nucleus of the amygdala. In contrast, cessation of freezing behavior correlated with a delayed and prolonged increase in serotonin release within the medial prefrontal cortex. Our findings suggest that corticotrophin-releasing factor-induced freezing behavior is associated with regionally and temporally distinct serotonergic responses in the limbic system that may reflect differing roles for these regions in the expression of fear/anxiety behavior.

Associations between a polymorphism in the 11 beta hydroxysteroid dehydrogenase type I gene and body composition

We investigated 11 beta hydroxysteriod dehydrogenase type 1 (11betaHSD-1) sequence variants in 103 healthy overweight (BMI >2 s.d.) and 160 nonoverweight (BMI -2 to +2 SD) children to examine the associations between body composition and 11betaHSD-1 polymorphisms. A total of 4.3% of children were homozygous and 30.0% heterozygous for an adenine insertion in intron 3 (ins4436A). By ANCOVA (adjusting for age, sex, race, and height), BMI-s.d. differed according to ins4436A genotype (P<0.005), with the greatest BMI-SD for ins4436A homozygotes (mean +/-s.d., 3.4+/-3.4, vs heterozygotes, 0.8+/-5.5, or wild-type, 1.8+/-7.5). Homozygotes also had greater waist circumference, waist-to-hip ratio, and insulin resistance indices than heterozygote or wild-type children (all P<0.05), but no significant differences in trunk fat by DXA, or in serum lipids. We conclude an intronic 11betaHSD-1 gene polymorphism is associated with greater body mass, altered body composition, and insulin resistance in children. 11betaHSD-1 may be one of the genes relevant for pediatric-onset obesity and its complications.

[Gene polymorphism at apoB locus and the serum lipids profile in children]

The relations of gene polymorphism at the apolipoprotein B locus and serum lipid profile in children was studied in 308 normal 7-11 year-old children, including 151 boys and 157 girls. Blood samples were collected for all subjects, and then the serum and blood clot were separated. Serum lipids, including TC, TG, LDL-C, HDL-C, apoB, apoA I and Lp(a) were detected. Genome DNA was extracted from blood clot, then apoB-Xba I gene polymorphism were tested by PCR-RFLP method. The results showed that the distribution of apoB-Xba I genotype in 308 children accorded with Hardy-Weiberg inheritance equilibrium law. The frequency of heterozygote(+/-) was 13.3%, allele(+) was 0.067. The frequency of allele(+) was closed to the internal and Japanese reports (0.033 and 0.04), but much less than the Caucasians (0.50). This showed a ethnic and population difference in the inheritance variation. The average LDL-C levels of the heterozygotes(+/-) were 2.17 mmol/L, no difference compared with homozygotes(-/-) (2.21 mmol/L, P > 0.05). There was also no difference for the genotype distribution between the hyperlipidemia group and control group, which may be the results of no enough sample size and the sample selection, and so on. On the other hand, in normal children, serum lipids controlled by many genes, the effect of a single gene might be small. More studies and analysis on the relationship between serum lipids and multiple genes in multisites should be the next step.

[Relationship between gene polymorphism at the apolipoprotein E locus and serum lipid profile in urban children of school age in Beijing]

OBJECTIVE

To study the relationship between gene polymorphism at the apolipoprotein E (ApoE) locus and serum lipid levels in children of school age.

METHODS

Blood samples were collected from 307 normal children aged 7 to 11 years, including 150 boys and 157 girls, and their serum lipid profile, including total cholesterol (TC), triglyceride (TG), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol (HDL-C), apolipoprotein B(apoB), apoprotein A1 (ApoA I) and lipoptoein alpha[LP (alpha)], were detected and their ApoE-Hha I gene polymorphism were tested by the PCR-RFLP method.

RESULTS

The detection rates for the most frequent genotype ApoE3/3 was 54.7%, other genotypes E4/3, E4/4, E3/2, E4/2 and E2/2 were 23.8%, 9.1%, 8.1%, 3.9% and 0.3%, respectively, in 307 children, with no significant difference between girls and boys(P > 0.05). Frequency of the often seen allele E3 was 70.7%, and that of E4 and E2 was 23.0% and 6.4, respectively, with E4 significantly higher than and E2 similar to that in the other domestic reports. The levels of TC, LDL-C, ApoA I and ApoB were higher in boys with genotypes E4/3 and E3/3 than those with genotypes E3/2 and E4/2. Levels of TC and ApoA I in the boys with genotype E3/2 were higher, with TC of 4.28 mmol/L and ApoA I of 3.41 mmol/L. There were no significant difference in serum lipid levels of girls with different genotypes(P > 0.05). There also was no significant difference in the ApoE-Hha I genotype distribution between normal children and those with high TC. ApoE2 could decrease the level of TC by 0.377 mmol/L, and LDL-C by 0.329 mmol/L.

CONCLUSIONS

Serum level of TC associated with polymorphism of ApoE gene carrier in boys, with the lowest levels of TC, LDL-C and ApoE in three with allele E2.

Rotavirus assembly - interaction of surface protein VP7 with middle layer protein VP6

The interaction between the rotavirus proteins viral protein 6 (VP6) and VP7 was examined in several exogenous protein expression systems. These proteins associated in the absence of other rotaviral proteins as demonstrated by a coimmunoprecipitation assay. Deletion analysis of VP7 indicated that truncations of either the mature amino or carboxyl terminus disrupted the proper folding of the protein and were not able to coimmunoprecipitate VP6. Truncation analysis of VP6 indicated that trimerization of VP6 was necessary, but not sufficient, for VP7 binding. MAb mapping and coimmunoprecipitation interference assays indicate that the VP6 amino acid residues between 271 and 342 are required for VP7 interaction. The interaction of VP6 and VP7 was also examined by the assembly of soluble VP7 onto baculovirus-expressed virus-like particles containing VP2 and VP6. Abrogation of this binding by preincubation of the particles with VP6 MAbs mapped to this same domain of VP6, validated our coimmunoprecipitation results. VP6 IgA MAbs that have been shown to be protective in vivo, but not a nonprotective IgA MAb, can interfere with VP7 binding to VP6. This suggests that these IgA MAbs may protect against rotavirus infection by blocking rotavirus assembly.

Hypercholesterolemia alters vascular functions and gene expression of potassium channels in rat aortic smooth muscle cells

AIM

To investigate the effects of hypercholesterolemia on functions of rat aorta and on gene expression of inward rectifier and ATP-sensitive potassium channels in aortic smooth muscle.

METHODS

Rats were treated with high-cholesterol emulsion ig for 2 weeks; the aortic rings with and without endothelium were prepared to examine the aortic contractile and relaxation responses; RT-PCR was used to observe the gene expression of inward rectifier and ATP-sensitive potassium channels.

RESULTS

Hypercholesterolemia damaged the endothelium-dependent vascular functions severely, but did not affect the endothelium-independent vascular functions; Kir6.2 mRNA expression was upregulated (P < 0.05) and Kir3.1 mRNA expression was downregulated markedly (P < 0.05) in hypercholesterolemic smooth muscle.

CONCLUSION

Hypercholesterolemia altered the vascular functions and regulated gene expression levels of specific inward rectifier and ATP-sensitive potassium channel subtypes.

Protective intestinal anti-rotavirus B cell immunity is dependent on alpha 4 beta 7 integrin expression but does not require IgA antibody production

Rotavirus (RV) is the main cause of severe gastroenteritis in young children; protection has been correlated with intestinal Ab responses. Using a mouse model of RV infection and beta(7)-deficient (beta(7)(-/-)) mice, which do not express alpha(4)beta(7) integrin, we demonstrated the importance of alpha(4)beta(7) integrin in B cell-mediated anti-RV immunity. beta(7)(-/-) mice acutely infected with murine RV resolved infection and developed normal serum IgG Abs but had diminished intestinal IgA responses. alpha(4)beta(7)(-/-) immune B cells did not resolve RV infection when adoptively transferred into RV-infected Rag-2-deficient mice. Fewer RV-specific B cells were found in the intestine of Rag-2-deficient mice transferred with beta(7)(-/-) B cells compared with wild type. The absence of alpha(4)beta(7) expression and/or a lower frequency of IgA-producing cells among transferred beta(7)(-/-) B cells could have accounted for the inability of these cells to resolve RV infection following passive transfer. To distinguish between these possibilities, we studied the importance of IgA production in RV infection using IgA-deficient (IgA(-/-)) mice. IgA(-/-) mice depleted of CD8(+) T cells were able to clear primary RV infection. Similarly, adoptive transfer of immune IgA(-/-) B cells into chronically infected Rag-2-deficient mice resolved RV infection. We further demonstrated in both wild-type and IgA(-/-) mice that, following oral RV infection, protective B cells reside in the alpha(4)beta(7)(high) population. Our findings suggest that alpha(4)beta(7) integrin expression is necessary for B cell-mediated immunity to RV independent of the presence of IgA.

The binding ability analysis of the normal VLDL receptor and its mutant

The ligand-binding domain of VLDL receptor contains eight imperfectly similar repeats. To discuss the contribution of each repeat to ligand binding, the RT-PCR technique was used to clone the VLDLR-cDNA from the heart muscle of Chinese people. Two recombinants were further constructed, which contained the full-length cDNA of VLDLR and the mutant lacking repeats 1-5. CHO cell line was transfected with two recombinants. The expression of VLDLR gene could be detected by RT-PCR from the CHO cells transfected with pCD-VR. The results of binding experiments showed that the ability of the CHO cells transfected with the full-length cDNA of VLDL-R binding DiI-labeled beta-VLDL was higher than that of the CHO cells transfected with the mutant. Our findings indicated that human VLDL-R gene could be expressed effectively on CHO cells, and the receptor was almost inactivated when repeats 1-5 were deleted.

alpha(4)beta(7) independent pathway for CD8(+) T cell-mediated intestinal immunity to rotavirus

Rotavirus (RV), which replicates exclusively in cells of the small intestine, is the most important cause of severe diarrhea in young children worldwide. Using a mouse model, we show that expression of the intestinal homing integrin alpha(4)ss(7) is not essential for CD8(+) T cells to migrate to the intestine or provide immunity to RV. Mice deficient in ss7 expression (ss7(-/-)) and unable to express alpha(4)ss(7) integrin were found to clear RV as quickly as wild-type (wt) animals. Depletion of CD8(+) T cells in ss7(-/-) animals prolonged viral shedding, and transfer of immune ss7(-/-) CD8(+) T cells into chronically infected Rag-2-deficient mice resolved RV infection as efficiently as wt CD8(+) T cells. Paradoxically, alpha(4)ss(7)(hi) memory CD8(+) T cells purified from wt mice that had been orally immunized cleared RV more efficiently than alpha(4)ss(7)(low) CD8(+) T cells. We explained this apparent contradiction by demonstrating that expression of alpha(4)ss(7) on effector CD8(+) T cells depends upon the site of initial antigen exposure: oral immunization generates RV-specific CD8(+) T cells primarily of an alpha(4)ss(7)(hi) phenotype, but subcutaneous immunization yields both alpha(4)ss(7)(hi) and alpha(4)ss(7)(low) immune CD8(+) T cells with anti-RV effector capabilities. Thus, alpha(4)ss(7) facilitates normal intestinal immune trafficking to the gut, but it is not required for effective CD8(+) T cell immunity.

[Micro determination of acrylonitrile in ambient air by gas chromatography]

Acrylonitrile in ambient air was collected by Tenax GC and then thermo-desorbed. It was separated on GDX-502 chromatographic column from other pollutants and determined by flame-ion ization detector. The minimum detectable concentration was 0.01 mg/m3 when 2 L ambient air was collected. The recoveries were 85.6%-105.4% and RSDs were 4.5%-6.2%.

Binding of interleukin-13 and interleukin-4 to the interleukin (IL)-4/IL-13 receptor of human synovial fibroblasts

Synovial fibroblasts expressed transcripts for IL-4R alpha, and IL-13R alpha 1 and IL-13R alpha 2. Using weighted nonlinear computer modeling of the data from equilibrium binding studies, a 2 bindings sites model fitted the data best. After occupation of the shared high affinity receptors by the non-signaling, double mutant IL-4(121)R-->D, 124Y-->D (RY-IL-4) the high affinity binding of IL-13 could be abolished. A 2 binding site model still could be fitted, however the improvement in fit over a onesite model was not statistically significant. Using affinity spectra, at least 2 binding sites are apparent. After treatment with RY-IL-4, some of the high affinity binding was abolished, however not completely. A correlation between the number of binding sites and the affinity is apparent, which seriously casts doubt on the classical evaluation of binding isotherms, where the parameters are assumed to be independent. In a previous study we suggested that the large number of IL-13R alpha 2 monomers are silent receptors, likely representing a decoy target for IL-13. The high affinity binding therefore most likely represents the binding to the heterodimer consisting of IL-4R alpha and IL-13R alpha 1 or IL-13R alpha 2. The low affinity binding may represent the IL-13R alpha 2.

The interleukin-4/interleukin-13 receptor of human synovial fibroblasts: overexpression of the nonsignaling interleukin-13 receptor alpha2

Interleukin (IL)-4 and IL-13 are known to bind to shared heteromultimeric receptor complexes of variable composition. Given the many regulatory effects of IL-4 and IL-13 on synovial cells, we aimed to characterize their IL-4/IL-13 receptor (R). Cultivated synovial fibroblasts expressed transcripts for IL-4Ralpha and IL-13Ralpha1, the human homolog of the recently cloned mouse IL-13R, but not the common gamma-chain of the IL-2R. In particular, IL-13Ralpha2 mRNA, encoding a different IL-13R recently cloned from human renal carcinoma cells, was expressed at a strikingly high level. Correspondingly, a predominant protein migrating at 65 to 75 kd was cross-linked by iodinated IL-13 and was not cross-competed by an excess of unlabeled IL-4. However, by flow cytofluorometry, IL-13Ralpha1 (detected by the anti-lL-13Ralpha1 mAb 65) and IL-4Ralpha (detected by the mAb S697) were expressed at similar low density. Radioligand binding studies revealed for both cytokines approximately 300 receptors/cell with similar high affinity. An additional class of IL-13Rs was identified after occupation of the shared high-affinity receptors by the nonsignaling, double-mutant IL-4121R-->D, 124Y-->D (RY-IL-4). In these experiments, 1251-IL-13 bound to a single receptor population with a Kd of approximately 300 pM and approximately 5000 sites/cell, matching the published affinity of monomeric IL-13Ralpha2 when expressed in COS7 cells. RY-IL-4 blocked the IL-4- and IL-13-mediated vascular cell adhesion molecule (VCAM)-1 expression and Stat6 activation, suggesting that the large number of high-affinity IL-13Ralpha2 monomers are silent receptors, likely representing a decoy target for IL-13.

Identification of mutations in the rotavirus protein VP4 that alter sialic-acid-dependent infection

To explore further the role of VP4 as the rotavirus cell attachment protein, VP7 monoreassortants derived from the sialic-acid-dependent simian strain RRV and from the sialic-acid-independent human strains D, DS-1 and ST-3 were tested for susceptibility of infectivity of neuraminidase-treated MA-104 cells. Infectivity of RRV x D VP7 and RRV x ST-3 VP7 monoreassortants decreased when sialic acid was removed from the cell surface. However, of three separate RRV x DS-1 VP7 monoreassortants tested, only one was sialic-acid-dependent. Sequence analysis showed that both sialic-acid-independent strains contained a single amino acid change, Lys to Arg, at position 187. In addition, sialic-acid-independent infectivity was seen in one of 14 RRV VP4 neutralization escape mutants tested, and this strain was found to have a Gly to Glu change at amino acid position 150. These results indicate that positions 150 and 187 of VP4 play an important role in early rotavirus-cell interactions.

[Association between levels of plasma lipid profile with apolipoprotein B gene polymorphism in 93 children]

OBJECTIVE

To study the relationship between levels of plasma lipid profile and variation of apolipoprotein (Apo) B gene.

METHODS

The relationship between frequency of polymorphism genotype of Apo B gene Xba I locus and levels of plasma lipid profile was studied in 93 children aged eight to eleven years.

RESULTS

The frequency of dominant X- allele (common allele) in Xba I locus was 0.967 in the children and that of uncommon X+ allele 0.033. Average levels of plasma total cholesterol (TC) and low density lipoprotein cholesterol (LDL-ch) in children with X- X+ genotype (4.59 and 2.98 mmol/L, respectively) were significantly higher than those with X-X- genotype (3.84 and 2.32 mmol/L, respectively). Levels of TC and/or LDL-ch in 4 of 6, cases of X-X+ genotype exceeded their the 90th percentile, indicating association between X+ allele and high plasma cholesterol level.

CONCLUSION

To certain extent, there is association between polymorphism of Xba I locus of Apo B gene and levels of plasma lipid profile in children, which may be a genetic marker for abnormal level of plasma lipid profile during childhood.

Studies of the role for NSP4 in the pathogenesis of homologous murine rotavirus diarrhea

A rotavirus (RV) nonstructural protein, NSP4, has recently been proposed to function as an enterotoxin in the pathogenesis of RV diarrhea. The role of NSP4 in the pathogenesis of RV diarrhea was examined by infecting cystic fibrosis transmembrane conductance regulator (CFTR) knockout mice with virulent murine RV and by comparing deduced amino acid sequences of RV gene 10 encoding NSP4 from three distinct sets of virulent and tissue culture-adapted avirulent variant RVs. Homozygous CFTR (CFTR-/-) mice, which do not respond to any known intestinal secretagogues, experienced diarrhea comparable to that in normal CFTR+/+ littermates after RV challenge. Comparison of amino acid sequences of NSP4 from virulent and attenuated pairs of RVs failed to show consistent or significant changes. Together, these data suggest that enterotoxigenic properties of RV NSP4 are not critical in the pathogenesis of murine RV diarrhea and that attenuation of murine RVs is not usually mediated by mutations in the gene encoding NSP4.

Investigation of the metabolism of 7-(4-chlorbenzyl)-7,8,13,13a-tetrahydroberberine chloride in the rat

The metabolism of 7-(4-chlorbenzyl)-7,8,13,13a-tetrahydroberberine chloride (CTHB), a compound with promising pharmacological effects against arrhythmia, was investigated in rat bile. A metabolite and unchanged CTHB were found in the bile. Characterization and structural elucidation of the metabolite was achieved by LC/MS and LC/NMR. The following metabolic pathway is proposed: CTHB is metabolized by demethylation at position 10 to produce a new entity.

Immune responses to individual rotavirus proteins following heterologous and homologous rotavirus infection in mice

Serum and intestinal humoral immune responses to rotavirus proteins VP2, VP4, VP6, VP7, NSP2, and NSP4 were quantitatively compared in mice infected with a homologous murine rotavirus (EHPw) or a heterologous simian rotavirus (RRV). Viral protein-specific antibody responses were measured by an immunohistochemistry assay that uses recombinant baculovirus-expressed rotavirus proteins as antigens. In serum, IgG responses to VP6 were dominant and comparable in both RRV- and EHPw-infected groups, but responses to VP2, VP4, VP7, and NSP2 were higher in RRV infection. In feces, IgA responses to VP2, VP4, and VP6 were higher in EHPw-infected mice, but responses to VP7 and NSP2 were detected only in the RRV-infected group. These findings indicate that immune responses to homologous and heterologous rotavirus infection vary both quantitatively and qualitatively. Differences in humoral responses may play a role in the differences in protection induced following homologous or heterologous rotavirus infection.

Tumor necrosis factor alpha enhances the expression of the interleukin (IL)-4 receptor alpha-chain on endothelial cells increasing IL-4 or IL-13-induced Stat6 activation

Functional receptors for interleukin (IL)-4 and IL-13 on endothelial cells consist of the 130-kDa IL-4 receptor alpha-chain (IL-4Ralpha) and a 65-75-kDa IL-13 binding subunit that are expressed in a ratio of about 1:3, respectively. The restricted number of IL-4Ralpha limits subunit heterodimerization and in turn receptor-mediated signaling. We report here, the effects of tumor necrosis factor alpha (TNF-alpha) on the expression of the receptor subunits for IL-4 and IL-13. By flow cytofluorometry and receptor-binding analysis of iodinated IL-4 and IL-13, stimulation with TNF-alpha-induced a 2-3-fold increase of the IL-4Ralpha expression. The up-regulation was also confirmed at the transcriptional level by reverse transcription-polymerase chain reaction. Radioligand cross-linking experiments revealed no change in the subunit composition of the TNF-alpha-induced receptor complex. Nevertheless, TNF-alpha stimulation led to increased activation of the IL-4-specific signal transducers and activators of transcription protein (Stat6) by IL-4 and IL-13. Thus, TNF-alpha corrects the subunit imbalance of the endothelial IL-4.IL-13 receptor complex thereby increasing receptor heterodimerization and in turn the signaling capability by IL-4 and IL-13.

Heterotypic protection following oral immunization with live heterologous rotaviruses in a mouse model

A Jennerian approach using live animal viruses to immunize humans is the current lead strategy for developing rotavirus vaccines. This strategy has been modified by incorporating human rotavirus VP7 genes into vaccine strains to induce serotype-specific neutralizing antibodies to human strains. However, the role of homotypic versus heterotypic immunity in protection is unclear. To investigate the importance of serotype-specific immunity in a mouse model, mice were immunized with rhesus rotavirus (RRV: G3, P5[3]), RRV-based modified Jennerian vaccine strains DxRRV (G1, P5[3]), DS1xRRV (G2, P5[3]), or ST3xRRV (G4, P5[3]), or bovine rotavirus NCDV (G6, P6[1]) and challenged with murine rotavirus ECw (G3, P[16]). Mice immunized with modified Jennerian vaccines exhibited complete to near-complete protection from challenge. NCDV-immunized mice also showed partial protection. The protection was correlated with fecal IgA levels to VP6, not serum IgG responses. Modified Jennerian vaccines induce both heterotypic and homotypic immunity in mice.

[A prevalence study on risk factors of cardiovascular disease during childhood]

A small size of sample for risk factors of cardiovascular disease, such as blood pressure, plasma lipids profile, obesity, dietary status, and family history of cardiovascular disease, etc. were studied in children aged eight to eleven years. Results showed that prevalence of hypertension, systolic blood pressure > 16.0 kPa (120 mmHg) or/and diastolic blood pressure > 10.7 kPa (80 mmHg), in them was 7.2 percent, blood lipid level in 21.9 percent of the children exceeded the recommended criteria of dietary intervention, and prevalence of simple obesity was 11.7 percent. The most prominent problem in dietary status was high cholesterol intake, with a daily intake of 483.4 mg in average, and 72 percent of the children exceeded 300 mg daily, as compared with previous data, and they exposure to higher level of risk factors for cardiovascular disease. It suggests that it is necessary to strengthen surveillance for risk factors of cardiovascular disease and intervention.

Murine model of rotavirus infection

The murine model of homologous rotavirus infection has been used to study the determinants of protection. The local IgA immune response appears to be the critical factor in generating protective immunity after natural infection. A series of knockout mice were used to evaluate the contribution of T cells and B cells to immunity and resolution from primary infection. Both arms of immune system played a role in the resolution of primary infection but antibody was much more important for prevention of reinfection.

Molecular determinants of immunity and pathogenicity of rotavirus infection in the mouse model

Rotavirus-induced diarrhea is responsible for the death of approximately 800,000 children per year. Jennerian and modified Jennerian anti-rotavirus vaccines currently being tested have a moderate protective effect against rotavirus disease. Optimization of these vaccines, development of more efficient rationally designed vaccines, and identification of other strategies to prevent or treat rotavirus disease will rely on a thorough understanding of the host-virus relationship and especially on the immune mechanisms developed by the host against rotavirus. Recent advances in our understanding of the mouse model of rotavirus infection will enhance the understanding of human rotavirus disease.

Neuroendocrine regulation of cytokine production during experimental influenza viral infection: effects of restraint stress-induced elevation in endogenous corticosterone

A murine model of influenza viral infection was used to examine the neuroendocrine regulation of cytokine production. Restraint stress (RST) was used to activate the hypothalamic-pituitary-adrenal axis and elevate corticosterone (CORT) levels in influenza A/Puerto Rico/8/34 (PR8) virus-infected C57BL/6 mice. The type II glucocorticoid receptor antagonist RU486 was used to specifically examine the modulation of PR8 virus-specific cytokine responses by CORT. RST suppressed the PR8 virus- specific production of Th1-type (IL-2 and IFN-gamma) and Th2-type IL-10) cytokines by cells from the regional lymph nodes and spleens. In addition, IL-6 production by splenocytes was inhibited by RST; however, IL-6 production by cells from the regional lymph nodes was enhanced. Treatment of mice with RU486 prevented the effects of RST, suggesting that the RST-induced alterations in cytokine responses were mediated by CORT. Furthermore, CORT was shown to inhibit the PR8 virus-specific production of both Thl-type and Th2-type cytokines in vitro at doses corresponding to the physiologic range of free plasma CORT following hypothalamic-pituitary-adrenal axis activation.

Neuroendocrine regulation of cytokine production during experimental influenza viral infection: effects of restraint stress-induced elevation in endogenous corticosterone

A murine model of influenza viral infection was used to examine the neuroendocrine regulation of cytokine production. Restraint stress (RST) was used to activate the hypothalamic-pituitary-adrenal axis and elevate corticosterone (CORT) levels in influenza A/Puerto Rico/8/34 (PR8) virus-infected C57BL/6 mice. The type II glucocorticoid receptor antagonist RU486 was used to specifically examine the modulation of PR8 virus-specific cytokine responses by CORT. RST suppressed the PR8 virus- specific production of Th1-type (IL-2 and IFN-gamma) and Th2-type IL-10) cytokines by cells from the regional lymph nodes and spleens. In addition, IL-6 production by splenocytes was inhibited by RST; however, IL-6 production by cells from the regional lymph nodes was enhanced. Treatment of mice with RU486 prevented the effects of RST, suggesting that the RST-induced alterations in cytokine responses were mediated by CORT. Furthermore, CORT was shown to inhibit the PR8 virus-specific production of both Thl-type and Th2-type cytokines in vitro at doses corresponding to the physiologic range of free plasma CORT following hypothalamic-pituitary-adrenal axis activation.

Quantification of systemic and local immune responses to individual rotavirus proteins during rotavirus infection in mice

The purpose of the present study was to develop a quantitative assay that could be used to measure the local and systemic immune responses to specific rotavirus proteins following rotavirus infection of adult mice. To measure these responses, we used an immunocytochemical staining assay of Spodoptera frugiperda (Sf-9) cells which were infected with recombinant baculovirus expressing selected rotavirus proteins. The specificity of the assay was documented by using a series of monoclonal antibodies to individual rotavirus proteins. We observed that the assay had high levels of sensitivity and specificity for a series of VP7- and VP4-specific neutralizing monoclonal antibodies which recognized conformation-dependent epitopes on their target proteins. We also studied immunoglobulin G (IgG) immune responses in serum and IgA immune responses in the stools of mice infected with wild-type murine rotavirus strain EHPw. In both sera and stools, the most immunogenic proteins were VP6 and VP4. VP2 was less immunogenic than VP6 or VP4, and the immune responses to VP7, NSP2, and NSP4 were very low in serum and undetectable in stools.

Interleukin-4 (IL-4) and IL-13 bind to a shared heterodimeric complex on endothelial cells mediating vascular cell adhesion molecule-1 induction in the absence of the common gamma chain

Interleukin-4 (IL-4) and IL-13 exert similar, nonadditive effects on endothelial cells, inducing vascular cell adhesion molecule-1 (VCAM-1) expression and subsequent transmigration of eosinophils. The receptor for IL-4 and IL-13 was described as a shared heteromultimeric complex in which the common gamma-chain (gamma c) subunit was essential for activity. Endothelial cell bound both cytokines with high affinity; by flow cytofluorometry and reverse transcription-polymerase chain reaction (RT-PCR), they expressed IL-4 receptor alpha (IL-4R alpha) but did not express the gamma c of the IL-2R. Radioligand cross-linking experiments followed by immunoprecipitation with the monoclonal antibody (MoAb) S697 to the IL-4R alpha showed IL-4-specific binding at 130 kD, the IL-4R alpha, and to a minor extent to a double band coimmunoprecipitated at 65 to 75 kD. [125 I]IL-13 bound predominantly to the 65- to 75- kD band and with a trace amount of binding at 130 kD. However, no ligand-cross-linked receptor was precipitated by the MoAb S697, indicating a cognate novel IL-13-binding subunit. Excess unlabeled IL-4 completely displaced IL-13 binding. Similarly, nonsignaling IL-4 (Y124D)-mutant abolished IL-4- and IL-13-mediated signal transduction. Unlabeled IL-13 competed successfully for IL-4 binding at 65 to 75 kD but was unable to completely displace Il-4 from its binding to the IL-4R alpha. The MoAb TUGh4, specific for the gamma c, failed to precipitate ligand-cross-linked IL-4R and IL-13R. Therefore, the subunit structure of the functional receptors for IL-4 and IL-13 on human endothelial cells does not use or require the common gamma c of the IL-2R.

Rotavirus immunity in the mouse

Naturally attenuated animal rotaviruses have been tested as antirotavirus vaccines with moderate success. The development of improved vaccines will rely on our understanding of the immune mechanism that mediate clearance and protection from rotaviral reinfection. The mouse model of rotavirus infection is a versatile tool for studying these mechanisms: mice have a relative low cost and there is a rapidly increasing number of immunological reagents to study rotavirus immunology. This review covers recent data on the mouse model of rotavirus infection. We show that both effector arms of the immune system (CD8 + T cells and B cells) mediate anti-rotavirus effects in vivo.

Genetic mapping indicates that VP4 is the rotavirus cell attachment protein in vitro and in vivo

To identify the rotavirus protein which mediates attachment to cells in culture, viral reassortants between the simian rotavirus strain RRV and the murine strains EHP and EW or between the simian strain SA-11 and the human strain DS-1 were isolated. These parental strains differ in the requirement for sialic acid to bind and infect cells in culture. Infectivity and binding assays with the parental and reassortant rotaviruses indicate that gene 4 encodes the rotavirus protein which mediates attachment to cells in culture for both sialic acid-dependent and -independent strains. Using ligated intestinal segments of newborn mice and reassortants obtained between the murine strain EW and RRV, we developed an in vivo infectivity assay. In this system, the infectivity of EW was not affected by prior treatment of the enterocytes with neuraminidase, while neuraminidase treatment reduced the infectivity of a reassortant carrying gene 4 from RRV on an EW background more than 80% relative to the controls. Thus, VP4 appears to function as the cell attachment protein in vivo as well as in vitro.

Characterization of interleukin-13 receptor in carcinoma cell lines and human blood cells and comparison with the interleukin-4 receptor

The interleukin-13 receptor is characterized by ligand-binding and crosslinking studies and compared with the interleukin-4 receptor. Crosslinking of radio-labeled hIL-4 and hIL-13 to the receptors on human carcinoma and mast cell lines demonstrated a predominant subunit at 130 kDa with two other minor bands of lower molecular mass (75 kDa and 65 kDa) in autoradiography. All binding of 125I-IL-13 was specifically blocked when the carcinoma cell suspensions were incubated with an excess of unlabeled hIL-4. However, unlabeled hIL-13 was unable to completely displace 125I-hIL-4 from the 130 kDa protein. In addition, 125I-hIL-13 showed no binding to mouse fibroblast cells transfected with human 130 kDa hIL-4 receptor c-DNA. Using weighted nonlinear computer modeling of the data from several equilibrium binding studies with human mast cells, a model of two binding sites for IL-4 (Kd = 50 and 190 pmol/L) and one site for IL-13 (Kd = 100 pmol/L) fitted better than a one site model with a very high level of significance (F = 10.66, P < 0.0001). It can be concluded that human IL-4R and hIL-13R are similar but distinct. This conclusion is supported here for the first time by a strong statistical criterion.

Development of a gas chromatography-mass spectrometry method for determination of ketamine in plasma and its application to human samples

A sensitive and precise gas chromatography-mass spectrometry method with selected ion monitoring has been developed for identification and quantification of the phencyclidine derivative ketamine in human plasma. The assay is based on an alkaline extraction from aqueous to organic solvent from plasma and an efficient gas chromatographic separation on a DB-5 capillary column. The analytical procedure has a coefficient of variation of 0.7-6.2% and from 1.3 to 8.7% within-day and from day-to-day analysis, respectively. The low level of sensitivity was 10 ng/ml. It was used to measure low plasma concentrations in volunteers during ketamine-induced experimental psychosis. The method is not enantio selective.

Comparison of mucosal and systemic humoral immune responses and subsequent protection in mice orally inoculated with a homologous or a heterologous rotavirus

Rotaviruses are the single most important cause of severe diarrhea in young children worldwide, and vaccination is probably the most effective way to control the disease. Most current live virus vaccine candidates are based on the host range-restricted attenuation of heterologous animal rotaviruses in humans. The protective efficacy of these vaccine candidates has been variable. To better understand the nature of the heterologous rotavirus-induced active immune response, we compared the differences in the mucosal and systemic immune responses generated by heterologous (nonmurine) and homologous (murine) rotaviruses as well as the ability of these infections to produce subsequent protective immunity in a mouse model. Sucking mice were orally inoculated with a heterologous simian or bovine rotavirus (strain RRV or NCDV) or a homologous murine rotavirus (wild-type or tissue culture-adapted) strain EHP at various doses. Six weeks later, mice were challenged with a virulent murine rotavirus (wild-type strain ECW) and the shedding of viral antigen in feces was quantitated. Levels of rotavirus-specific serum immunoglobulin G (IgG) and fecal IgA prior to challenge were measured and correlated with subsequent viral shedding or protection. Heterologous rotavirus-induced active protection was highly dependent on the strain and dose of the virus tested. Mice inoculated with a high dose (10(7) PFU per mouse) of RRV were completely protected, while the protection was diminished in animals inoculated with NCDV or lower doses of RRV. The ability of a heterologous rotavirus to stimulate a detectable intestinal IgA response correlated with the ability of the virus to generate protective immunity. Serum IgG titer did not correlate with protection. Homologous rotavirus infection, on the other hand, was much more efficient at inducing both mucosal and systemic immune responses as well as protection regardless of the virulence of the virus strain or the size of the immunizing dose.

Peptide vaccines incorporating a 'promiscuous' T-cell epitope bypass certain haplotype restricted immune responses and provide broad spectrum immunogenicity

An ideal peptide vaccine should contain both B- and T-cell epitopes. Recognition of antigen by B cells is highly dependent on the three-dimensional conformation of the antigen whereas T cells recognize antigen only after it has been processed to release a peptide fragment which is bound to the major histocompatibility complex (MHC) class II molecule. However, T cells provide 'help' to B cells displaying the same processed, MHC-restricted form of the antigen, demonstrating that the T-cell response to a protein antigen is under genetic control. Thus, strategies for co-inclusion of T cell 'helper' epitopes with the B-cell determinant elicit immune responses that are in most cases genetically restricted to only one or a few alleles of the MHC with limited activity across divergent MHC class II haplotypes. This genetically restricted T cell stimulatory activity of peptides is a serious obstacle and consequently such constructs would be of limited practical value as a vaccine targeted to a majority of an outbred population. In the study described here, we have engineered two peptides to encompass the sequences from the universally immunogenic tetanus toxoid (TT) epitope and the contraceptive vaccine candidate lactate dehydrogenase C4 (LDH-C4). We demonstrate the feasibility of using 'promiscuous' T-cell epitopes colinearly constructed with a defined B-cell epitope to induce high titer antipeptide IgG antibodies specific for native protein antigen LDH-C4 in several inbred strains of mice, outbred mice and rabbits. There appears to be a strong correlation between the capacity for the hybrid peptides to be stimulatory for the corresponding T cells in C57BL/6 (H-2b) and C3H/HeJ (H-2k) mice and their ability to be immunogenic. This correlation, however, appears to break down in H-2d strains of mice since no antibodies were detected in BALB/c and barely detectable levels of antibodies in B10.D2 although activated T cells were detectable. Conversely, high titers of antipeptide antibodies are elicited in some strains (B10.BR (H-2k); C57BL/10 (H-2b) without detectable IL-2 responses. Finally, we show that a determinant which was previously restricted to H-2k can be rendered immunogenic in H-2b with the 'promiscuous' TT epitope. Thus, certain haplotype-restricted immune responses can be bypassed, setting forth the ground work for the design of a universal vaccine by broadening the effective response in a larger number of individuals typical of the genetically diverse outbred human population.

The effect of adrenalectomy on the restraint stressed induced suppression of MHC class II expression by murine peritoneal macrophages

Restraint stress suppresses the expression of MHC class II (I-A) glycoproteins by murine peritoneal macrophages. In order to evaluate the role of the pituitary adrenal axis, the effect of restraint stress on I-A expression by macrophages from adrenalectomized mice was evaluated. Adrenalectomy resulted in elevated levels of ACTH but abrogated the increase in corticosterone that results from restraint stress. The expression of I-A by macrophages from adrenalectomized mice was similar to that of sham operated mice or untreated mice. Adrenalectomy ameliorated the suppressive effects of restraint but the expression of I-A was below that of macrophages from adrenalectomized control mice. These results suggest that other factors in addition to corticosterone may effect I-A expression by murine peritoneal macrophages. A survey of other neuropeptides and catecholamines indicated that the addition of ACTH or epinephrine to macrophage cultures resulted in a suppression of I-A expression.

Stress-induced modulation of the primary cellular immune response to herpes simplex virus infection is mediated by both adrenal-dependent and independent mechanisms

A murine model of herpes simplex virus (HSV) infection was used to examine the role of the adrenal gland in restraint stress-induced suppression of viral immunity. Adrenal-dependent mechanisms were important for suppressing the generation of HSV-specific cytotoxic T lymphocytes (CTL) but not the associated diminished lymphadenopathy in response to local HSV infection. While exogenous corticosterone administration alone was unable to suppress lymphadenopathy and CTL generation in adrenalectomized mice, an adrenal-independent mechanism induced by restraint stress functioned in synergy with corticosterone to suppress lymphadenopathy and CTL development. These results suggest that both adrenal-dependent and independent mechanisms contribute to stress-induced modulation of HSV immunity.

Flow cytometry for analyzing changes in irradiated and heated HeLa S3 cells

In the present study, we have compared the distribution in various phases, DNA content, cell survival and ultrastructure of HeLa S3 cells after irradiation and/or hyperthermia. After 220 KV X-ray irradiation, the Do of the survival curve was 0.94 Gy, Dq was 1.3 Gy, and N was 4.26. After Ir-192 gamma-ray irradiation, the Do of the survival curve was 2.26 Gy, Dq was 3.9 Gy, and N was 5.7. The Do of the survival curve of HeLa S3 cells after treatment at 43.5 degrees C and 44 degrees C was 2.2 min and 1.6 min, respectively. Ultrastructural changes were also observed. The marked increase of the DNA content after 6 Gy irradiation corresponded with changes of distribution in various phases, which indicated a delay in the G2 + M phase. The survival fraction after 6 Gy irradiation was less than 1%. The changes of cell cycle distribution after Ir-192 irradiation were similar to those seen after X-ray exposure. The delay of G2 + M phase after hyperthermia was dose-dependent. An obvious delay of the G2 + M phases was also observed at 24 h after treatment with X-rays plus hyperthermia.