The Role of Latency-Associated Transcripts in the Latent Infection of Pseudorabies Virus

Pseudorabies virus (PRV) can cause neurological, respiratory, and reproductive diseases in pigs and establish lifelong latent infection in the peripheral nervous system (PNS). Latent infection is a typical feature of PRV, which brings great difficulties to the prevention, control, and eradication of pseudorabies. The integral mechanism of latent infection is still unclear. Latency-associated transcripts (LAT) gene is the only transcriptional region during latent infection of PRV which plays the key role in regulating viral latent infection and inhibiting apoptosis. Here, we review the characteristics of PRV latent infection and the transcriptional characteristics of the LAT gene. We also analyzed the function of non-coding RNA (ncRNA) produced by the LAT gene and its importance in latent infection. Furthermore, we provided possible strategies to solve the problem of latent infection of virulent PRV strains in the host. In short, the detailed mechanism of PRV latent infection needs to be further studied and elucidated.

Supplementation of H7N9 Virus-Like Particle Vaccine With Recombinant Epitope Antigen Confers Full Protection Against Antigenically Divergent H7N9 Virus in Chickens

The continuous evolution of the H7N9 avian influenza virus suggests a potential outbreak of an H7N9 pandemic. Therefore, to prevent a potential epidemic of the H7N9 influenza virus, it is necessary to develop an effective crossprotective influenza vaccine. In this study, we developed H7N9 virus-like particles (VLPs) containing HA, NA, and M1 proteins derived from H7N9/16876 virus and a helper antigen HMN based on influenza conserved epitopes using a baculovirus expression vector system (BEVS). The results showed that the influenza VLP vaccine induced a strong HI antibody response and provided effective protection comparable with the effects of commercial inactivated H7N9 vaccines against homologous H7N9 virus challenge in chickens. Meanwhile, the H7N9 VLP vaccine induced robust crossreactive HI and neutralizing antibody titers against antigenically divergent H7N9 viruses isolated in wave 5 and conferred on chickens complete clinical protection against heterologous H7N9 virus challenge, significantly inhibiting virus shedding in chickens. Importantly, supplemented vaccination with HMN antigen can enhance Th1 immune responses; virus shedding was completely abolished in the vaccinated chickens. Our study also demonstrated that viral receptor-binding avidity should be taken into consideration in evaluating an H7N9 candidate vaccine. These studies suggested that supplementing influenza VLP vaccine with recombinant epitope antigen will be a promising strategy for the development of broad-spectrum influenza vaccines.

Derivation of an electronic frailty index for short-term mortality in heart failure: a machine learning approach

Objective

Frailty may be found in heart failure patients especially in the elderly and is associated with a poor prognosis. However, assessment of frailty status is time-consuming and the electronic frailty indices developed using health records have served as useful surrogates. We hypothesized that an electronic frailty index developed using machine learning can improve short-term mortality prediction in patients with heart failure.

Methods

This was a retrospective observational study included patients admitted to nine public hospitals for heart failure from Hong Kong between 2013 and 2017. Age, sex, variables in the modified frailty index, Deyo's Charlson comorbidity index (≥2), neutrophil-to-lymphocyte ratio (NLR) and prognostic nutritional index (PNI) were analyzed. Gradient boosting, which is a supervised sequential ensemble learning algorithm with weak prediction submodels (typically decision trees), was applied to predict mortality. Variables were ranked in the order of importance with a total score of 100 and used to build the predictive models. Comparisons were made with decision tree and multivariate logistic regression.

Results

A total of 8893 patients (median: age 81, Q1-Q3: 71–87 years old) were included, in whom 9% had 30-day mortality and 17% had 90-day mortality. PNI, age and NLR were the most important variables predicting 30-day mortality (importance score: 37.4, 32.1, 20.5, respectively) and 90-day mortality (importance score: 35.3, 36.3, 14.6, respectively). Gradient boosting significantly outperformed decision tree and multivariate logistic regression (area under the curve: 0.90, 0.86 and 0.86 for 30-day mortality; 0.92, 0.89 and 0.86 for 90-day mortality).

Conclusions

The electronic frailty index based on comorbidities, inflammation and nutrition information can readily predict mortality outcomes. Their predictive performances were significantly improved by gradient boosting techniques.

Funding Acknowledgement

Type of funding sources: None.

The effectiveness of traditional Chinese medicine fumigation and washing nursing care after arthroscopic debridement of Knee Osteoarthritis: A protocol for systematic review and meta-analysis

BACKGROUND

Knee Osteoarthritis (KOA) is a degenerative osteoarthrosis with knee joint pain as the main symptom. In recent years, arthroscopic removal of loose body and repair of meniscus have become common methods for the treatment of KOA. However, postoperative pain, swelling and limited joint movement affect the functional recovery of knee joint and the effect of surgical treatment. Early postoperative control of pain and swelling is of great significance to improve the curative effect of arthroscopic debridement and promote the recovery of knee joint function. In recent years, many clinical studies have reported that the nursing method of fumigation and washing with Chinese medicine after arthroscopic debridement of KOA can relieve pain, promote the recovery of joint function and improve the clinical curative effect, but there is a lack of evidence-based medicine. The purpose of this study is to evaluate the efficacy and safety of fumigation and washing with traditional Chinese medicine after KOA arthroscopy.

METHODS

Computer retrieval English database (PubMed, Embase, Web of Science, the Cochrane Library) and Chinese database (China National Knowledge Infrastructure, Wanfang, VIP Database for Chinese Technical Periodicals, China Biology Medicine disc), moreover manual retrieval academic, Google and baidu from building to since December 2020, traditional Chinese medicine fumigation applied to KOA arthroscopy postoperative nursing of randomized controlled clinical research, by two researchers independently evaluated the quality of the included study and extracted the data. Meta-analysis of the included literatures was performed using RevMan5.3 software.

RESULTS

The main observation index of this study was the effective rate, and the secondary indexes included Visual Analogue Scale Score, the Western Ontario and McMaster university orthopedic index, Lysholms score and adverse reactions, so as to evaluate the efficacy and safety of traditional Chinese medicine fumigation nursing after KOA arthroscopy.

CONCLUSION

This study will provide reliable evidence for the clinical application of Fumigation and washing nursing of traditional Chinese medicine after KOA arthroscopy.

ETHICS AND DISSEMINATION

Private information from individuals will not be published. This systematic review also does not involve endangering participant rights. Ethical approval will not be required. The results may be published in a peer-reviewed journal or disseminated at relevant conferences.

OSF REGISTRATION NUMBER

DOI 10.17605/OSF.IO/THZP4.

The Network of Interactions Between Classical Swine Fever Virus Nonstructural Protein p7 and Host Proteins

Classical swine fever (CSF) is a highly contagious viral disease causing severe economic losses to the swine industry. As viroporins of viruses modulate the cellular ion balance and then take over the cellular machinery, blocking the activity of viroporin or developing viroporin-defective attenuated vaccines offers new approaches to treat or prevent viral infection. Non-structural protein p7 of CSF virus (CSFV) is a viroporin, which was highly involved in CSFV virulence. Deciphering the interaction between p7 and host proteins will aid our understanding of the mechanism of p7-cellular protein interaction affecting CSFV replication. In the present study, seven host cellular proteins including microtubule-associated protein RP/EB family member 1 (MAPRE1), voltage-dependent anion channel 1 (VDAC1), proteasome maturation protein (POMP), protein inhibitor of activated STAT 1 (PIAS1), gametogenetin binding protein 2 (GGNBP2), COP9 signalosome subunit 2 (COPS2), and contactin 1 (CNTN1) were identified as the potential interactive cellular proteins of CSFV p7 by using yeast two-hybrid (Y2H) screening. Plus, the interaction of CSFV p7 with MAPRE1 and VDAC1 was further evaluated by co-immunoprecipitation and GST-pulldown assay. Besides, the p7-cellular protein interaction network was constructed based on these seven host cellular proteins and the STRING database. Enrichment analysis of GO and KEGG indicated that many host proteins in the p7-cellular protein interaction network were mainly related to the ubiquitin-proteasome system, cGMP-PKG signaling pathway, calcium signaling pathway, and JAK-STAT pathway. Overall, this study identified potential interactive cellular proteins of CSFV p7, constructed the p7-cellular protein interaction network, and predicted the potential pathways involved in the interaction between CSFV p7 and host cells.

[Expression and significance of PD-1 and PD-L1 in the specimens of epithelial ovarian cancer]

Objective: To examine the expression of programmed cell death 1 (PD-1) and its ligand (PD-L1) in epithelial ovarian cancer (EOC) tissues, and investigate the correlation among their expression, clinicopathological features and prognosis. Methods: The specimens of 180 patients with EOC treated in the First Affiliated Hospital of Dalian Medical University from October 2002 to December 2013 were confirmed by pathological examination. The pathological tissue specimens of subtypes ，included 120 cases of serous carcinoma, 30 cases of mucinous carcinoma, 20 cases of endometrioid carcinoma, and 20 cases of clear cell carcinoma. The normal paracancerous tissues of 50 cases randomly selected from the 180 patients as control group. Immunohistochemical SP method was used to detect the expressions of both PD-1 and PD-L1 in epithelial ovarian cancer tissues, and the relationships among their expressions,the clinicopathological parameters and prognosis were respectively analyzed. Results: （1） PD-1 was expressed in lymphocytes infiltrated in EOC tissues, and PD-L1 was expressed in the cell membranes of cancer tissues. In all EOC cases, 33 cases (18.3%, 33/180) of both PD-1 and PD-L1 were highly expressed, and only 1 (2.0%, 1/50) of control group showed high expression. There was statistically significant difference between two groups (P<0.01). (2) Among the four subtypes tissue specimens of EOC, the high expression rate of PD-1 was 25.0% (30/120) for serous carcinoma, 3/15 for endometrioid carcinoma, 0 (0/30) for mucinous carcinoma, and 0 (0/15) for clear cell carcinoma. The high expression rate of PD-L1 was 23.3% (28/120) for serous carcinoma, 3.3% (1/30) for mucinous carcinoma, 2/15 for endometrioid carcinoma, and 2/15 for clear cell carcinoma. Both PD-1 and PD-L1 expressions in the four sub-types of tissue specimens were significantly different (P<0.05). The high expression rate of both PD-1 and PD-L1 was 9.2% (8/87) in the early stage and 26.9% (25/93) in the late stage. There was a statistically significant difference between the two groups (P<0.01). Similarly, the expression of both PD-1 and PD-L1 were significantly higher in the cases of high-grade EOC （type Ⅱ） than those of low-grade （type Ⅰ） and in the cases of EOC distributed bilaterally than that distributed unilaterally, and there were statistically significant differences (P<0.05). (3) The Kaplan-Meier survival analysis showed that the survival time were respectively 35 and 36 months in the cases with high expressions of both PD-1 and PD-L1, and the survival time were the same as 61 months in the cases with low expression of both PD-1 and PD-L1, and the comparison was statistically significant (P<0.05). Conclusions: The expression levels of PD-1 and PD-L1 in EOC tissues are higher than those in adjacent tissues, especially in serous carcinomas. The expression of both PD-1 and PD-L1 is higher in specimens of the patients with advanced stages. The results showed that the high expression of both PD-1 and PD-L1 is an indicator of poor prognosis of patients suffering from EOC.

Overcoming Hypoxia-Restrained Radiotherapy Using an Erythrocyte-Inspired and Glucose-Activatable Platform

Radiotherapy (RT) as one of the most powerful cancer treatment strategies has been greatly restricted by tumor hypoxia. A mounting effort has been devoted to develop oxygen delivery systems for boosting the RT effect. Unluckily, those systems only supplied modest oxygen, which could not afford more than once and long-time RT. Herein, we describe the development of a glucose-regulated drug release platform, allowing for a long-term tumor normoxic microenvironment and repeated RT for a long time. The repeated cycles resulted in sustained high Endostar plasma levels, which dramatically normalized the tumor vasculature and chronically reversed tumor hypoxia. Taking advantage of the inexhaustible supply of oxygen, Endo@GOx-ER enabled RT achieved an impressive cancer treatment output. To the best of our knowledge, our strategy is the initial attempt to overcome tumor-hypoxia-limited RT through the normalization of tumor vasculature by using an erythrocyte-inspired and glucose-activatable platform and it visually casts a light on the clinical development.

Effect of peer support on diabetes distress: a cluster randomized controlled trial

AIM

To investigate whether peer support would reduce diabetes distress and improve glycaemic control when added to usual diabetes education among adults with Type 2 diabetes in China.

METHODS

We conducted a cluster randomized trial involving 400 adults with Type 2 diabetes from eight communities in Nanjing. All participants received usual education for an average of 2 h each month from physicians, certified diabetes educators, dieticians, psychologists and podiatric nurses. Peer support was led by trained peer leaders and included diabetes knowledge- and skills-sharing at least once a month, as well as peer-to-peer communication. The primary outcome was diabetes distress measured using the Diabetes Distress Scale at 12 months. Secondary outcomes included fasting plasma glucose, 2-h postprandial glucose and HbA_1c concentration. Outcome data were collected from all participants at baseline, 6 months and 12 months.

RESULTS

From 2012 to 2013, there were 200 participants in each study arm at baseline. Compared with the usual education arm, the peer support with usual education arm had greater reductions in regimen-related distress (1.4 ± 0.6 vs 1.2 ± 0.4; P=0.004) and total distress (1.3 ± 0.4 vs 1.2 ± 0.3; P=0.038) at 6 months. At 12 months, the scores for emotional burden (1.2 ± 0.3 vs 1.4 ± 0.6; P=0.002), physician-related distress (1.1 ± 0.3 vs 1.3 ± 0.4; P=0.001) and total scores (1.2 ± 0.3 vs 1.3 ± 0.4; P=0.002) were significantly lower in the peer support with usual education arm than in the usual education arm. Fasting plasma glucose levels were lower in the peer support with usual education arm than in the usual education arm at 6 months (7.5 ± 1.95 vs 8.0 ± 2.2; P=0.044) and 12 months (7.0 ± 2.3 vs 7.6 ± 1.5; P=0.008).

CONCLUSIONS

Beyond the benefits of usual education, peer support was effective in reducing diabetes distress for Type 2 diabetes mellitus. (Clinical Trials Registry no: NCT02119572).

Third- and high-order nonlinear optical properties of an intramolecular charge-transfer compound

An oligo(phenylenevinylene) bridged intramolecular charge-transfer (ICT) compound, (TCNQ)2OPV3, has been synthesized and its third- and fifth-order nonlinear optical properties have been determined by measurement with the 4f system with a phase-object.

Genome-Wide Transcriptional Profiling Reveals Two Distinct Outcomes in Central Nervous System Infections of Rabies Virus

Rabies remains a major public health concern in many developing countries. The precise neuropathogenesis of rabies is unknown, though it is hypothesized to be due to neuronal death or dysfunction. Mice that received intranasal inoculation of an attenuated rabies virus (RABV) strain HEP-Flury exhibited subtle clinical signs, and eventually recovered, which is different from the fatal encephalitis caused by the virulent RABV strain CVS-11. To understand the neuropathogenesis of rabies and the mechanisms of viral clearance, we applied RNA sequencing (RNA-Seq) to compare the brain transcriptomes of normal mice vs. HEP-Flury or CVS-11 intranasally inoculated mice. Our results revealed that both RABV strains altered positively and negatively the expression levels of many host genes, including genes associated with innate and adaptive immunity, inflammation and cell death. It is found that HEP-Flury infection can activate the innate immunity earlier through the RIG-I/MDA-5 signaling, and the innate immunity pre-activated by HEP-Flury or Newcastle disease virus (NDV) infection can effectively prevent the CVS-11 to invade central nervous system (CNS), but fails to clear the CVS-11 after its entry into the CNS. In addition, following CVS-11 infection, genes implicated in cell adhesion, blood vessel morphogenesis and coagulation were mainly up-regulated, while the genes involved in synaptic transmission and ion transport were significantly down-regulated. On the other hand, several genes involved in the MHC class II-mediated antigen presentation pathway were activated to a greater extent after the HEP-Flury infection as compared with the CVS-11 infection suggesting that the collaboration of CD4⁺ T cells and MHC class II-mediated antigen presentation is critical for the clearance of attenuated RABV from the CNS. The differentially regulated genes reported here are likely to include potential therapeutic targets for expanding the post-exposure treatment window for RABV infection.

Phosphorylation of CHIP at Ser20 by Cdk5 promotes tAIF-mediated neuronal death

Cyclin-dependent kinase 5 (Cdk5) is a proline-directed serine/threonine kinase and its dysregulation is implicated in neurodegenerative diseases. Likewise, C-terminus of Hsc70-interacting protein (CHIP) is linked to neurological disorders, serving as an E3 ubiquitin ligase for targeting damaged or toxic proteins for proteasomal degradation. Here, we demonstrate that CHIP is a novel substrate for Cdk5. Cdk5 phosphorylates CHIP at Ser20 via direct binding to a highly charged domain of CHIP. Co-immunoprecipitation and ubiquitination assays reveal that Cdk5-mediated phosphorylation disrupts the interaction between CHIP and truncated apoptosis-inducing factor (tAIF) without affecting CHIP's E3 ligase activity, resulting in the inhibition of CHIP-mediated degradation of tAIF. Lentiviral transduction assay shows that knockdown of Cdk5 or overexpression of CHIP(S20A), but not CHIP(WT), attenuates tAIF-mediated neuronal cell death induced by hydrogen peroxide. Thus, we conclude that Cdk5-mediated phosphorylation of CHIP negatively regulates its neuroprotective function, thereby contributing to neuronal cell death progression following neurotoxic stimuli.

Production of monoclonal antibody against EP0 protein of pseudorabies virus and determination of its recognized epitope

Early protein 0 (EP0) is especially important for modulating PRV gene expression and reactivation from the latent state, but the mechanisms have not been elucidated. In this study, six monoclonal antibodies (MAbs) against EP0 protein of PRV were generated and their characterizations were investigated. Western blot analysis showed all six MAbs could react with immunizing antigen, but only 2B12 and 2C6 could react with native EP0 protein from PRV-infected cells. ELISA additivity tests revealed that at least three epitopes in EP0 were defined by six MAbs. The epitope recognized by MAb 2B12 was further identified in 287-292 aa of EP0 protein using a series of expressed overlapping peptides. These MAbs may provide valuable tools for further research of the functions of EP0 in PRV infection.

Genetic diversity and positive selection analysis of classical swine fever virus isolates in south China

Classical swine fever virus (CSFV) causes a highly contagious disease that leads to significant economic losses in the pig industry worldwide. However, there is a paucity of knowledge on the accurate genotyping of CSFV isolates in south China. This study genotyped the E2 gene of 14 CSFV strains isolated during 2008-2010 from domestic pigs in different districts of south China. Phylogenetic analyses revealed that all of the 14 CSFV isolates were clustered into genetic subgroup 1.1. This contrasts with most parts of China, where group 2 isolates are predominant. Furthermore, the positive selection pressures acting on the E(rns) and E2 envelope protein genes of CSFV were assessed and a site-by-site analysis of the dN/dS ratio was performed to identify specific codons that undergo diversification under positive selection. While no significant evidence for positive selection was observed in E(rns), two positively selected sites at amino acid residues 49 and 72 in the E2 encoding region were identified. Our results revealed that a predominance of subgroup 1.1 CSFV isolates is currently circulating in some districts of south China, which appear to be unrelated to the Chinese C-strain vaccine. Moreover, the envelope protein gene, E2, has undergone positive selection in 14 CSFV strains and two positively selected sites have been identified in this study. Understanding the molecular epidemiology and functional importance of these positively selected amino acid positions could help to predict possible changes in virulence, the development of vaccines and disease control.

Immunogenicity of Empty Capsids of Porcine Circovius Type 2 Produced in Insect Cells

Porcine circovirus type 2 (PCV2), a single-stranded DNA virus, is associated with postweaning multisystemic wasting syndrome (PMWS). ORF2 protein (capsid) of PCV2 was recently demonstrated to be a major immunogenable to induce protection in pigs with a prime-boost protocol. In this study, the ORF2 gene of PCV2 was expressed in insect cells. The product self-assembled into particles that were structurally and antigenically indistinguishable from regular PCV2 capsids. To evaluated the immunogenicity of these virus-like particles, PCV2-free piglets were vaccinated with the crude lysate from recombinant baculovirus (Ac.ORF2)-infected insect cells, at doses of 0.1 ml (10(6) cells), 0.5 mL (5 x 10(6) cells) or 1.0 ml (10(7) cells). The immune response was monitored by an indirect enzyme-linked immunosorbent assay (ELISA) for PCV2 antibody and lymphocyte proliferation assay. The ELISA results indicated that primary immune response was elicited with 0.5 ml or 1.0 ml of crude lysate from Ac.ORF2. After boost immunization, relatively higher levels of PCV2 antibody were elicited in 0.5-ml or 1.0-ml vaccinated groups, compared to the 0.1-ml group. In addition, higher PCV2 specific lymphocyte proliferation response was developed in piglets vaccinated with 0.5 ml or 1.0 ml of crude lysate, especially in those vaccinated with with 1.0 ml of crude lysate. Thus, the expressed ORF2 protein has significant potential as a subunit vaccine against PCV2 infection.

Immunogenicity of a recombinant pseudorabies virus expressing ORF1–ORF2 fusion protein of porcine circovirus type 2

Porcine circovirus type 2 (PCV2) is associated with post-weaning multisystemic wasting syndrome (PMWS). Pseudorabies (PR) is also an important infectious disease in swine and sometimes co-infect with PCV2. An attenuated pseudorabies virus (PRV) has been successfully used as a vector for live viral vaccines. In this study, a recombinant PRV expressing ORF1-ORF2 fusion protein of PCV2 was constructed and its immunogenicity was tested in mice and pigs. The ORF1 and partial ORF2 gene of PCV2 Yu-A strain were amplified by PCR and inserted into a transfer vector. The recombinant transfer plasmid was co-transfected with the EcoRI digested genome of vector virus (PRV TK-/gE-/LacZ+) into IBRS-2 cells. The recombinant pseudorabies virus PRV-PCV2 was purified by plaque purification and identified by PCR and Southern blotting. Expression of the ORF1-ORF2 fusion protein by the recombinant PRV-PCV2 virus was demonstrated by Western blotting analysis. The growth properties of the recombinant virus in cells were similar to that of the parent vector virus. In animal experiments, PRV-PCV2 elicited strong anti-PRV and anti-PCV2 antibodies in Balb/c mice as indicated by PRV-neutralizing assay, anti-PCV2 ELISA and PCV2 specific lymphocyte proliferation assay, respectively. And PRV-PCV2 immunization protected mice against a lethal challenge of a virulent PRV Ea strain. In pigs, PRV-PCV2 elicited significant immune response towards PRV and PCV2 as indicated by PRV-ELISA, PRV neutralizing assay and PCV2 specific lymphocyte proliferation assay, respectively. This is a first step toward the development of a potential candidate divalent vaccine against PRV and PCV2 infections.

Mechanism of idiosyncratic drug reactions: reactive metabolite formation, protein binding and the regulation of the immune system

Drug-induced adverse reactions, especially type B reactions, represent a major clinical problem. They also impart a significant degree of uncertainty into drug development because they are often not detected until the drug has been released onto the market. Type B reactions are also termed idiosyncratic drug reactions by many investigators due to their unpredictable nature and our lack of understanding of the mechanisms involved. It is currently believed that the majority of these reactions are immune-mediated and are caused by immunogenic conjugates formed from the reaction of a reactive metabolite of a drug with cellular proteins. It has been shown that most drugs associated with idiosyncratic reactions form reactive metabolites to some degree. Covalent binding of reactive metabolites to cellular proteins has also been shown in many cases. However, studies to reveal the role of reactive metabolites and their protein-adducts in the mechanism of drug-induced idiosyncratic reactions are lacking. This review will focus on our current understanding and speculative views on how a reactive metabolite of a drug might ultimately lead to immune-mediated toxicity.

Dehydroepiandrosterone inhibits the death of immunostimulated rat C6 glioma cells deprived of glucose

Pretreatment of interferon-gamma and lipopolysaccharides made C6 glioma cells highly vulnerable to glucose deprivation. Neither 12 h of glucose deprivation nor 2-day treatment with interferon-gamma (100 U/ml) and lipopolysaccharides (1 microg/ml) altered the viability of C6 glioma cells. However, significant death of immunostimulated C6 glioma cells was observed after 5 h of glucose deprivation. The augmented death was prevented by dehydroepiandrosterone (DHEA) treatment during immunostimulation, but not by DHEA treatment during glucose deprivation. DHEA reduced the rise in nitrotyrosine immunoreactivity, a marker of peroxynitrite, and superoxide production in glucose-deprived immunostimulated C6 glioma cells. DHEA, however, did not protect glucose-deprived C6 glioma cells from the exogenously produced peroxynitrite by 3-morpholinosydnonimine. Further, DHEA did not alter the production of total reactive oxygen species and nitric oxide in immunostimulated C6 glioma cells. Superoxide dismutase (SOD) and the synthetic SOD mimetic Mn(III)tetrakis (4-benzoic acid) porphyrin inhibited the death of glucose-deprived immunostimulated C6 glioma cells. In addition, a superoxide anion generator paraquat reversed the protective effect of DHEA on the augmented death. The data indicate that DHEA prevents the glucose deprivation-evoked augmented death by inhibiting the production of superoxide anion in immunostimulated C6 glioma cells.

Immunohistochemical detection of protein adducts of 2,4-dinitrochlorobenzene in antigen presenting cells and lymphocytes after oral administration to mice: lack of a role of Kupffer cells in oral tolerance

Although current studies suggest that most drug-induced allergic reactions (DIARS) are caused by immunogenic conjugates formed from the reaction of a reactive metabolite of a drug with cellular proteins, it is not clear why these reactions are relatively rare. One possible pathway that may explain the low incidence of DIARS in many cases is oral tolerance, an antigen-specific immunological hyporesponsiveness induced by oral administration of antigens. The mechanism of oral tolerance, however, is not clearly understood and is difficult to study directly with drugs, because animal models of DIARS have been elusive. We chose 2,4-dinitrochlorobenzene (DNCB) as a model compound to circumvent this problem because animal models of allergic reactions have been established for this compound. DNCB forms immunogenic 2,4-dinitrophenylated (DNP) protein conjugates that can induce immune reactions and it causes oral tolerance when it is fed to animals prior to sensitization. We hypothesized that DNP-protein conjugates may have a role in oral tolerance. To test this idea, we have begun to identify cells bearing these conjugates after the oral administration of DNCB. Female C57BL/6J mice were fed DNCB and tissues were examined after 6 and 24 h. Immunohistochemical analysis indicated the presence of DNP-protein conjugates in enterocytes of the small intestine, in macrophages and lymphocytes of the mesenteric lymph nodes, in dendritic cells and lymphocytes of the spleen, and in Kupffer cells and other sinusoidal cells of the liver. It was found that Kupffer cell depletion did not affect oral tolerance to DNCB. The findings suggest that the cells bearing DNP-protein conjugates, other than Kupffer cells, in the liver and other tissues may be important in the induction of oral tolerance against DNCB. Protein adducts of drugs administered orally may also be present in these cells, and they may have a role in the downregulation of DIARS in many individuals.

Equivalent disruption of regional white matter microstructure in ageing healthy men and women

Diffusion tensor imaging was used to measure regional differences in brain white matter microstructure (intravoxel coherence) and macrostructure (intervoxel coherence) and age-related differences between men and women. Neuropsychiatrically healthy men and women, spanning the adult age range, showed the same pattern of variation in regional white matter coherence. The greatest coherence measured was in corpus callosum, where commissural fibers have one primary orientation, lower in the centrum semiovale, where fibers cross from multiple axes, and lowest in pericallosal areas, where fibers weave and interstitial fluid commonly pools. Age-related declines in intravoxel coherence was equally strong and strikingly similar in men and women, with evidence for greater age-dependent deterioration in frontal than parietal regions. Degree of regional white matter coherence correlated with gait, balance, and interhemispheric transfer test scores.

Protection by a manganese porphyrin of endogenous peroxynitrite-induced death of glial cells via inhibition of mitochondrial transmembrane potential decrease

In the cerebral ischemic penumbra, progressive metabolic deterioration eventually leads to death of glial cells. The exact mechanism for the death of glial cells is unclear. Here we report that under glucose-deprived conditions immunostimulated glial cells rapidly underwent death via production of large amounts of peroxynitrite. The cell-permeable Mn(III)tetrakis(N-methyl-4'-pyridyl)porphyrin (MnTMPyP) caused a concentration-dependent attenuation of the increased death in glucose-deprived immunostimulated glial cells. The structurally related compound H(2)TMPyP, which lacks metals, did not attenuate this augmented cell death. MnTMPyP prevented the elevation in nitrotyrosine immunoreactivity (a marker of ONOO(-)) in glucose-deprived immunostimulated glial cells. In glucose-deprived glial cells, MnTMPyP also completely blocked the augmented death and nitrotyrosine immunoreactivity induced by the ONOO(-)-producing reagent 3-morpholinosydnonimine (SIN-1). The mitochondrial transmembrane potential (MTP), as measured using the dye JC-1, was rapidly decreased in immunostimulated or SIN-1-treated glial cells deprived of glucose. MnTMPyP, but not H(2)TMPyP, blocked the depolarization of MTP in those glial cells. The present data, at least in part, provide evidence for how glial cells die in the postischemic and/or recurrent ischemic brain.

Interleukin-6 and interleukin-8 levels in serum and synovial fluid of patients with osteoarthritis

Concentrations of interleukin (IL)-6 and IL-8 in serum and synovial fluid obtained from patients with osteoarthritis (OA) of the knee were determined by the chemiluminescence-ELISA (CL-ELISA) method, the sensitivity of which is 100-1,000 times greater than that of the conventional ELISA method. The results were compared with those obtained from patients with rheumatoid arthritis (RA) and from healthy subjects. The mean IL-6 and IL-8 levels in synovial fluid indicated higher concentrations in RA than in OA. The IL-6 and IL-8 levels in serum were significantly higher in RA and OA relative to controls. Among OA patients in whom remarkable improvement was noted in hydrarthrosis, the synovial fluid IL-6 and IL-8 levels at the initial examination were relatively higher, and were markedly decreased after treatment with sodium hyaluronate (NaHA). Among those in whom no improvement was noted in hydrarthrosis, the synovial fluid IL-6 and IL-8 levels at the time of initial examination were relatively lower, and hydrarthrosis was not significantly improved even after treatment with NaHA. In addition, there was a tendency for the synovial fluid IL-6 and IL-8 levels to decrease as HA levels increased. Evaluation of X-ray findings revealed that the IL-6 levels in synovial fluid at the initial examination in low-grade cases tended to be significantly higher than in high-grade cases. In low-grade cases, as determined by X-ray findings, there was a significant decrease in IL-6 levels in synovial fluid after treatment with NaHA.

Radon awareness, testing, and remediation survey among New York State residents

Between November 1995 and January 1997, a radon awareness, testing, and remediation survey was conducted to measure general awareness and factual knowledge about radon and prevalence of radon testing and remediation among New York State residents. The survey found that 82% of 1,209 respondents had heard of radon, but only 21% were knowledgeably aware of radon. With regard to radon testing, only 15% of respondents who were aware of radon had their homes tested. The percentage of respondents who were aware or knowledgeably aware of radon increased with increasing education level. The findings from the study suggest that the New York State public awareness programs that targeted high radon areas did show some effect both by increasing public awareness and promoting residential testing. The relatively low percentage of respondents who were knowledgeably aware of radon and the low percentage who had tested their homes strongly suggest that renewed efforts by the public health community are needed to increase knowledge about radon and its health effects and to encourage radon testing and remediation.

Synergistic depletion of astrocytic glutathione by glucose deprivation and peroxynitrite: correlation with mitochondrial dysfunction and subsequent cell death

Previously we reported that immunostimulated astrocytes were highly vulnerable to glucose deprivation. The augmented death was mimicked by the peroxynitrite (ONOO )-producing reagent 3-morpholinosydnonimine (SIN-1). Here we show that glucose deprivation and ONOO- synergistically deplete intracellular reduced glutathione (GSH) and augment the death of astrocytes via formation of cyclosporin A-sensitive mitochondrial permeability transition (MPT) pore. Astrocytic GSH levels were only slightly decreased by glucose deprivation or SIN-1 (200 microM) alone. In contrast, a rapid and large depletion of GSH was observed in glucose-deprived/ SIN-1-treated astrocytes. The depletion of GSH occurred before a significant release of lactate dehydrogenase (a marker of cell death). Superoxide dismutase and ONOO-scavengers completely blocked the augmented death, indicating that the reaction of nitric oxide with superoxide to form ONOO was implicated. Furthermore, nitrotyrosine immunoreactivity (a marker of ONOO-) was markedly enhanced in glucose-deprived/SIN-1 -treated astrocytes. Mitochondrial transmembrane potential (MTP) was synergistically decreased in glucose-deprived/SIN-1-treated astrocytes. The glutathione synthase inhibitor L-buthionine-(S,R)-sulfoximine markedly decreased the MTP and increased lactate dehydrogenase (LDH) releases in SIN-1-treated astrocytes. Cyclosporin A, an MPT pore blocker, completely prevented the MTP depolarization as well as the enhanced LDH releases in glucose-deprived/SIN-1-treated astrocytes.

[The public health significance of the measurement of cytokines in serum]

As variable functions of cytokines have been proved in recent years, cytokine levels in biological fluids such as serum, plasma, and synovial fluid of patients with every kind of disease have been enthusiastically measured. As a result, many studies have shown an increase or decrease in the production of cytokines or abnormal cytokine levels in biological fluids. However, the relationship between the abnormal levels of cytokines and the intensity of the clinical symptoms or the prognosis remains unclear. The significance for the measurement of cytokines depends on whether it should be valid for detecting a preclinical status such as AST or ALT used for health checks or for disease screening such as some tumor markers. The purpose of this study is to know whether or not some cytokine levels in serum could be biomarkers for preventive purposes. Serum cytokine levels (IL-4, 6, 8, 12, and IFN-gamma) were measured in three different types of cohorts (nursery school infants, manufacturing workers and middle and old aged women) with chemiluminescence ELISA. The results showed no differences with atopic status in infants, pulmonary fibrosis in workers or with the decrease in bone stiffness, these results are mainly due to a great inter-individual variability of serum cytokine levels. This study concludes that serum cytokine levels are inappropriate as biomarkers for preventive purposes. However, a further detailed evaluation in healthy people with high serum cytokine levels may be necessary.

Radon mitigation survey among New York State residents living in high radon homes

Residential exposure to radon has been considered an important environmental risk factor for lung cancer. Since 1986, U.S. EPA has recommended that all dwellings below the third floor be tested for the presence of radon and be mitigated to reduce indoor radon in homes with levels exceeding 148 Bq m(-3). In order to evaluate the effectiveness of New York State Department of Health's efforts to increase public awareness about radon risk and to promote radon testing and mitigation in compliance with EPA's guideline, a statewide radon mitigation survey was conducted between September 1995 and January 1996 among New York State residents whose homes had radon levels equal to or greater than 148 Bq m(-3) on the first floor (or above) living areas. The survey found that about 60% of 1,113 participants had taken actions for radon mitigation. The percentage of respondents who took actions to reduce radon levels in their homes increased with increasing education level as well as household income level. The method of installing a powered system to provide more ventilation was a more effective mitigation method than opening widows/doors or sealing cracks/openings in the basement. Mitigation performed by contractors was more effective in reducing radon levels than mitigation performed by residents. The reasons for performing radon mitigation given by the majority of respondents were those strongly related to radon health risk. High home radon level was an important motivational factor to stimulate radon mitigation. On the other hand, the cost of radon mitigation was a major barrier in decision making for performing radon mitigation and for selecting mitigation measures. Thus, public educational campaigns that focus on increasing awareness and knowledge about radon health risks and development of less expensive radon mitigation methods may help in promoting radon mitigation.

Detection of 2-hydroxyiminostilbene in the urine of patients taking carbamazepine and its oxidation to a reactive iminoquinone intermediate

Carbamazepine is one of the most widely used anticonvulsants in North America; however, its use is associated with a range of serious idiosyncratic adverse reactions. These reactions are thought to result from the formation of chemically reactive metabolites. Carbamazepine is extensively metabolized in the liver and one of the major metabolites is 2-hydroxycarbamazepine, which has previously been detected as a urinary metabolite excreted by rats and humans along with its further metabolized product, 2-hydroxyiminostilbene. In this study, we found that the urine of patients taking carbamazepine appeared to contain more of the glucuronide of 2-hydroxyiminostilbene than that of 2-hydroxycarbamazepine. We have also demonstrated that 2-hydroxyiminostilbene can be oxidized readily to an iminoquinone species by HOCl, H2O2 or even on exposure to air. The reactivity of this iminoquinone as an electrophile was studied. It was shown to react with sulfhydryl-containing nucleophiles, such as glutathione and N-acetylcysteine. We also found a metabolite with the same molecular weight as 4-methylthio-2-hydroxyiminostilbene, but not the corresponding carbamazepine derivative, in the urine of patients taking carbamazepine and this presumably reflects the formation of a glutathione conjugate of the reactive iminoquinone. This iminoquinone intermediate may play a role in carbamazepine-induced idiosyncratic reactions.

Oxidation of a metabolite of indomethacin (Desmethyldeschlorobenzoylindomethacin) to reactive intermediates by activated neutrophils, hypochlorous acid, and the myeloperoxidase system

The use of indomethacin is associated with a relatively high incidence of adverse reactions such as agranulocytosis. Many other drugs associated with agranulocytosis are metabolized to reactive metabolites by activated neutrophils. Therefore, we studied the oxidation of indomethacin and its metabolites by activated neutrophils, myeloperoxidase (MPO) (the major oxidizing enzyme in neutrophils), and HOCl (the major oxidant produced by activated neutrophils). No oxidation of indomethacin by activated neutrophils was observed. However, desmethyldeschlorobenzoylindomethacin (DMBI), a major metabolite of indomethacin, was oxidized to a reactive iminoquinone that could be trapped with glutathione (GSH) or N-acetylcysteine (NAC) to form conjugates, with MH+ ions at m/z 511 and 367, respectively. No metabolism was detected in neutrophils that had not been activated, and the oxidation was inhibited by azide (which inhibits MPO) and by catalase (which catalyzes the breakdown of H2O2). In reactions with HOCl, the same reactive intermediate was formed; its mass spectrum, with a MH+ ion at m/z 204, was obtained by using a flow system in which the reactants were fed into a mixing chamber and the products flowed directly into the mass spectrometer. The same GSH and NAC conjugates were also observed when DMBI was oxidized by HOCl or by the MPO system, followed by addition of GSH or NAC. NMR data for the NAC conjugate indicated that the sulfur was substituted in the 4-position on the aromatic ring. The reactive intermediate generated from DMBI by activated neutrophils may be responsible for indomethacin-induced agranulocytosis.

[Comparative study on Legionella infection in different groups of population in Dalian area]

Using a microagglutination test, the prevalence of antibodies against three species (10 groups) of Legionella was determined in 300 healthy donors, 120 non-pneumonic patients with immunodeficiency and 158 patients with pneumonia. The results showed that there were significant differences among all groups on positive rate and GMT in three groups. Lp6 was the highest, Lp1 and Lp8 came second. There were significant differences among three groups in positive rate and GMT to Lp1, Lp2, Lp6 and Lp8, in the group of patients with pneumonia was highest, the group of non-pneumonic patients with immunodeficiency was second and healthy group was the lowest. It was suggested that the infection with Lp6, Lp1, Lp8 was predominant in population in Dalian area. The latent infection, subclinical infection and legionella pneumonia in population might be existence simultaneously. Using test-tube agglutination, the paired sera collected from 74 pneumonic patients were studied, it was showed that 5.4% of admitted pneumonic patients was legionellosis.

Infant leukemia and paternal exposure to motor vehicle exhaust fumes

The children of fathers who work in gas stations, automobile or truck repair, and aircraft maintenance appear to be at increased risk for acute leukemia during their first year of life. The odds ratio was found to be about 2.5 overall, but risk appears to be greater for female offspring. A decline in sex ratio was observed for the three decades of the study, with the lowest ratio observed from 1969 through 1978. These preliminary findings suggest that exposure to one or more of the components of exhaust fumes might be of etiologic importance for this malignancy. The limitations of this investigation are discussed.