Miltefosine reduces coxsackievirus B3 lethality of mice with enhanced STAT3 activation.

Coxsackievirus B3 (CVB3), one serotype of enteroviruses, can induce fatal myocarditis and hepatitis in neonates, but both treatment and vaccine are unavailable. Few reports tested antivirals to reduce CVB3. Several antivirals were developed against other enterovirus serotypes, but these antivirals failed in clinical trials due to side effects and drug resistance. Repurposing of clinical drugs targeting cellular factors, which enhance viral replication, may be another option. Parasite and cancer studies showed that the cellular protein kinase B (Akt) decreases interferon (IFN), apoptosis, and interleukin (IL)-6-induced STAT3 responses, which suppress CVB3 replication. Furthermore, miltefosine, the Akt inhibitor used in the clinic for parasite infections, enhances IL-6, IFN, and apoptosis responses in treated patients, suggesting that miltefosine could be the potential antiviral for CVB3. This study was therefore designated to test the antiviral effects of miltefosine against CVB3 in vitro and especially, in mice, as few studies test miltefosine in vitro, but not in vivo. In vitro results showed that miltefosine inhibited viral replication with enhanced activation of the cellular transcription factor, STAT3, which is reported to reduce CVB3 both in vitro and in mice. Notably, STAT3 knockdown abolished the anti-CVB3 activity of miltefosine in vitro. Mouse studies demonstrated that miltefosine pretreatment reduced CVB3 lethality of mice with decreased virus loads, organ damage, and apoptosis, but enhanced STAT3 activation. Miltefosine could be prophylaxis for CVB3 by targeting Akt to enhance STAT3 activation in the mechanism, which is independent of IFN responses and hardly reported in pathogen infections.

Acyclovir-resistant HSV-1 isolates among immunocompromised patients in southern Taiwan: Low prevalence and novel mutations.

Herpes simplex virus type 1 (HSV-1) can establish latency in humans and easily relapse in immunocompromised patients, with significant mortality. Treatment with acyclovir (ACV) can result in the emergence of HSV resistance. A total of 440 frozen HSV-1 isolates collected from 318 patients from January 2014 to July 2019 were obtained from National Cheng Kung University Hospital in southern Taiwan. These 440 isolates were subjected to phenotypic studies for ACV-resistance by initial screening with the plaque reduction assay (PRA) and further validation by the DNA reduction assay (DRA). The ACV-resistant strains were further investigated by Sanger sequencing for the full-length UL23 and UL30 genes, which encode thymidine kinase and DNA polymerase, respectively. Hematological malignancies or hematopoietic stem-cell transplantation patients accounted for 56.9% (124/218) among the immunocompromised patients (218/318) in this study. Repeated sampling for HSV testing was 50% (109/218) in immunocompromised patients. Only 1.38% (3/218) of immunocompromised patients and 0.9% (3/318) of all patients developed ACV-resistant HSV-1 as measured by phenotypic screening assays. It is noteworthy that a novel Y248D mutation in the UL23 gene from an immunocompromised patient was found by both PRA and DRA. In 3D protein predicting analysis, uncharged Y248 was located at an alpha-helix and substituted by negative-charged D248, which may alter the function of viral thymidine kinase. Besides, three unreported mutations related to natural polymorphism were found in virus isolates from two immunocompetent patients, including 683-688 deletion, R227H, and A351D in the UL30 gene. These data show that the prevalence of ACV-resistant HSV-1 among immunocompromised patients in southern Taiwan is low. These results will be helpful for the clinical management and treatment of HSV infections.

Clinical and Immune Responses of Peripheral Chemical Sympathectomy in Enterovirus 71 Infection.

The activation of the sympathetic nervous system, release of norepinephrine (NE), and adrenergic receptor signaling participate in and regulate the complicated enterovirus 71 (EV71) brainstem encephalitis (BE). The neurotoxin 6-hydroxydopamine (6-OHDA) selectively ablates sympathetic nerves and markedly depletes NE in innervated organs. Changes in the plasma levels of NE, severity score, cytokine profiles, and percentages of immunophenotype expression in 7-day-old Bltw : CD1 (ICR) mice infected with EV71, with or without 6-OHDA treatment, were compared. The survival rate (76.9%) of EV71-infected and 6-OHDA (30 µg/g)-treated mice was increased significantly. The clinical scores were decreased markedly on days 8-12 in MP4-infected and 6-OHDA-treated mice compared to those without treatment. The results showed that the plasma levels of NE, epinephrine, and dopamine were decreased on days 4-8 after 6-OHDA treatment and at most on day 8. The plasma levels of interleukin (IL)-12p70, tumor necrosis factor, IL-6, and IL-10 did not change significantly after 6-OHDA treatment. Interferon-γ levels decreased evidently on days 4, 6, and 8 after 6-OHDA treatment. The absolute events of CD3+CD4+, CD3+CD8+, and CD3+NK1.1+ cells of peripheral blood mononuclear cells were increased significantly in MP4-infected and 6-OHDA-treated mice compared to those without treatment. In splenocytes, the absolute cells of CD3-NK1.1+, CD3+NK1.1+ and CD11b+Gr-1+ cells of EV71-infected mice were increased significantly after 6-OHDA treatment. These findings suggested that 6-OHDA may be used a probe to explore clinical improvements and immune responses in the complicated EV71 infection. Taken together, peripheral chemical sympathectomy contribute to further understand the immunopathogenesis of EV71 BE with autonomic nervous system dysregulation.

Early-life EV-A71 infection augments allergen-induced airway inflammation in asthma through trained macrophage immunity.

Virus-induced asthma is prevalent among children, but its underlying mechanisms are unclear. Accumulated evidence indicates that early-life respiratory virus infection increases susceptibility to allergic asthma. Nonetheless, the relationship between systemic virus infections, such as enterovirus infection, and the ensuing effects on allergic asthma development is unknown. Early-life enterovirus infection was correlated with higher risks of allergic diseases in children. Adult mice exhibited exacerbated mite allergen-induced airway inflammation following recovery from EV-A71 infection in the neonatal period. Bone marrow-derived macrophages (BMDMs) from recovered EV-A71-infected mice showed sustained innate immune memory (trained immunity) that could drive naïve T helper cells toward Th2 and Th17 cell differentiation when in contact with mites. Adoptive transfer of EV-A71-trained BMDMs induced augmented allergic inflammation in naïve recipient mice, which was inhibited by 2-deoxy-D-glucose (2-DG) pretreatment, suggesting that trained macrophages following enterovirus infection are crucial in the progression of allergic asthma later in life.

Comparative study of clinical and epidemiological characteristics of major pediatric adenovirus epidemics in southern Taiwan.

BACKGROUND: Human adenoviruses (HAdV) are important pathogens of pediatric respiratory tract infections in Taiwan. There were two major HAdV epidemics in southern Taiwan in 2011 and 2014, respectively. METHODS: The demographic, clinical characteristics, and risk factors for hospitalization of pediatric patients with HAdV infection in the two outbreaks were retrospectively compared. The epidemic was defined as > 7% HAdV detection rate for six consecutive weeks. HAdV infection was defined as positive HAdV isolates from respiratory tract specimens. HAdV genotype was determined by PCR-based hexon gene sequencing. RESULTS: A total of 1145 pediatric patients were identified (635 cases in 2011; 510 cases in 2014). HAdV genotype 3 and 7 contributed to both epidemics, although the proportion of HAdV3 decreased significantly (64.7% in 2011 to 25.5% in 2014, p < 0.001) and was replaced by other genotypes (type 1, 4, and 6) in the 2014 epidemic. Among the hospitalized patients, there were more patients hospitalized with bronchopneumonia/or pneumonia in the 2011 epidemic (10.6% vs 5.1%, p < 0.001), while more patients hospitalized with acute pharyngitis/pharyngoconjunctival fever (63.9% vs. 38.6%, p < 0.001) in the 2014 epidemic. In both epidemics, hospitalized patients had higher WBC and C-reactive protein (CRP) levels than non-hospitalized patients. Using multivariate regression analysis, underlying disease and elevated CRP levels were independent risk factors for hospitalization in both epidemics. CONCLUSION: There were significant differences in clinical, viral characteristics and risk factors of hospitalization between the 2011 and 2014 epidemics. Understanding changes in the epidemiological and clinical characteristics of HAdV epidemics is important from a public health perspective.

Anti-inflammatory and antiviral effects of minocycline in enterovirus 71 infections.

Enterovirus 71 (EV71) brainstem encephalitis (BE) is divided into-uncomplicated BE, autonomic nervous system (ANS) dysregulation, and pulmonary edema (PE)-based on cytokine-mediated severe systemic and central nervous system (CNS) inflammatory responses. Minocycline has been found to have anti-inflammatory and immunomodulatory properties in infectious and inflammatory neurological disease models. The effects of minocycline on EV71 infection were studied in vitro and in vivo experiments. The minocycline treatment (100-300 µg/mL) on cytokine expressions and viral replications were investigated in rhabdomyosarcoma (RD), U-87MG, and THP-1 cells. The mouse-adapted-EV71 strain (MP4)-infected 7-day-old ICR mice model was used to explore the anti-inflammatory and antiviral effects of minocycline (1 and 5 µg/g) for the treatment of EV71 infection. In in vitro, minocycline reduced cytopathic effects (CPEs), viral protein expressions, viral titers, the levels of interleukin (IL)-6 and IL-8 and relative mRNA expressions of IL-12p40, IL-1ß, and tumor necrosis factor (TNF) after EV71 infection. The levels of TNF, IL-1ß, IL-6, and IL-8 decreased with a single dose of minocycline in EV71-infected THP-1 cells. Double-dose minocycline treatment demonstrated more effective reduction in cytokines. In the MP4-infected animal model, clinical scores, mortality rates and viral titers in various brain tissues were decreased evidently after double-dose minocycline treatment. Minocycline inhibited IL-6 and granulocyte colony-stimulating factor (G-CSF) in plasma and TNF in the cerebellum. Minocycline has properties that enable it to function both as an anti-inflammatory and antiviral agent in EV71 infection. These results evidence its potential usefulness in clinical treatment.

Suppression of interleukin-6 increases enterovirus A71 lethality in mice.

BACKGROUND: Enterovirus A71 (EV-A71) infection can induce fatal encephalitis in young children. Clinical reports show that interleukin-6 (IL-6) levels in the serum and cerebrospinal fluid of infected patients with brainstem encephalitis are significantly elevated. We used a murine model to address the significance of endogenous IL-6 in EV-A71 infection. RESULTS: EV-A71 infection transiently increased serum and brain IL-6 protein levels in mice. Most importantly, absence of IL-6 due to gene knockout or depletion of IL-6 using neutralizing monoclonal antibody enhanced the mortality and tissue viral load of infected mice. Absence of IL-6 increased the damage in the central nervous system and decreased the lymphocyte and virus-specific antibody responses of infected mice. CONCLUSIONS: Endogenous IL-6 functions to clear virus and protect the host from EV-A71 infection. Our study raises caution over the use of anti-IL-6 antibody or pentoxifylline to reduce IL-6 for patient treatment.

Antiviral activities of Schizonepeta tenuifolia Briq. against enterovirus 71 in vitro and in vivo.

No effective drug is currently available for treatment of enterovirus 71 (EV71) infection. Schizonepeta tenuifolia Briq. (ST) has been used as a herbal constituent of traditional Chinese medicine. We studied whether the aqueous extract of Schizonepeta tenuifolia Briq (STE) has antiviral activity. STE inhibited replication of EV71, as evident by its ability to diminish plaque formation and cytopathic effect induced by EV71, and to inhibit the synthesis of viral RNA and protein. Moreover, daily single-dose STE treatment significantly improved the survival of EV71-infected mice, and ameliorated the symptoms. Mechanistically, STE exerts multiple effects on enteroviral infection. Treatment with STE reduced viral attachment and entry; the cleavage of eukaryotic translation initiation factor 4 G (eIF4G) by EV71 protease, 2Apro; virus-induced reactive oxygen species (ROS) formation; and relocation of heterogeneous nuclear ribonucleoprotein A1 (hnRNP A1) from the nucleus to the cytoplasm. It was accompanied by a decline in EV71-associated hyperphosphorylation of p38 kinase and EPS15. It is plausible that STE may inhibit ROS-induced p38 kinase activation, and subsequent hnRNP A1 relocation and EPS15-mediated membrane trafficking in infected cells. These findings suggest that STE possesses anti-EV71 activities, and may serve as health food or candidate antiviral drug for protection against EV71.

Clinical features of community acquired adenovirus pneumonia during the 2011 community outbreak in Southern Taiwan: role of host immune response.

BACKGROUND: Human adenovirus 7 (HAdV-7) was responsible for a significant number of fatalities during the 2011 community outbreak in Taiwan. The mechanisms underlying the pathogenesis of severe adenovirus infections in non-immunocompromised individuals remain unclear. Adenovirus pneumonia was associated with pleural effusion in a number of patients from the 2011 outbreak suggesting that similar to bacterial pneumonia, patients diagnosed with adenovirus pneumonia who have pleural effusion are more severely and systemically infected, and may have a more protracted disease course. We hypothesized that the host immunological response determines the severity of adenoviral infection. METHODS: This retrospective case series study included patients diagnosed with severe lower respiratory tract infections at the National Cheng Kung University Hospital in southern Taiwan between December 2010 and October 2011. The main inclusion criteria were 1) presence of multifocal patchy infiltrates, lobar consolidation or reticular interstitial opacities in chest X-rays, and 2) presence of adenovirus isolated from respiratory specimens. All patients had adenovirus isolated from respiratory specimens, and were negative for other viruses. Pleural effusion was confirmed in all patients using chest echography. Clinical features and laboratory data were compared in patients with (n = 12) and without (n = 15) parapneumonic effusion. RESULTS: Presence of parapneumonic effusion was significantly associated with a longer febrile duration, more complicated clinical management, and a greater risk of extrapulmonary involvement, notably hepatitis. Patients without pleural effusion had significantly higher numbers of WBCs, platelets, and absolute segment cell counts (ASCs) compared to patients with pleural effusion (all p < 0.05). Patients without pleural effusion had significantly higher counts of CD4+, CD8+, and CD20+ T cells (all p < 0.05) compared to patients with pleural effusion. CONCLUSION: Our data indicated that presence of parapneumonic effusion in adenoviral pneumonia was associated with longer febrile duration, more complicated clinical management, a greater risk of hepatitis, and suppression of host cellular immunity. Further prospective, large-scale studies are needed to validate our results.

Bloodstream infections in pediatric patients with acute leukemia: Emphasis on gram-negative bacteria infections.

BACKGROUND/PURPOSE: Acute leukemia is the most common pediatric hematological malignancy. Bloodstream infections (BSIs) are severe complications in these patients during chemotherapy. This study aims to explore clinical features, laboratory, and microbiological characteristics of BSIs in acute leukemic children. METHODS: Patients aged < 18 years, diagnosed with acute myeloid leukemia or acute lymphocytic leukemia with BSIs from January 2004 to December 2013 were enrolled. BSIs was defined as positive isolate(s) of blood culture and associated with clinical findings. Clinical presentations, demographic features, and microbiological findings were retrospectively reviewed. RESULTS: In total, 126 isolates of 115 episodes of BSIs were identified from 69 patients (acute lymphocytic leukemia 56; acute myeloid leukemia 13). Gram-negative bacteria (GNB), gram-positive cocci, and fungi constituted 56.3%, 42.3%, and 2.4% of the pathogens, respectively. Eighty-three and a half percent of BSIs occurred along with neutropenia, and 73% had severe neutropenia. GNB was the leading pathogen of BSIs. The major GNBs were Escherichia coli, Klebsiella pneumonia, and Pseudomonas aeruginosa. White blood cell counts, absolute neutrophil counts, and platelet counts were significantly lower in patients of BSIs caused by GNB than gram-positive cocci. Plasma level of C-reactive protein was significant high in patients of GNB BSIs (179.8 mg/L vs. 127.2 mg/L; p = 0.005). Eighty-two percent of patients of E. coli, K. pneumonia, and P. aeruginosa BSIs had sepsis related organ failure or organ dysfunction. P. aeruginosa BSIs had the highest case-mortality (40%). CONCLUSION: Neutropenia was the major risk factor of BSIs in pediatric leukemic patients. BSIs of GNB were associated with severe neutropenia, systemic inflammatory responses, and high mortality.

Mapping Enterovirus A71 Antigenic Determinants from Viral Evolution.

UNLABELLED: Human enterovirus A71 (EV-A71) belongs to the Enterovirus A species in the Picornaviridae family. Several vaccines against EV-A71, a disease causing severe neurological complications or even death, are currently under development and being tested in clinical trials, and preventative vaccination programs are expected to start soon. To characterize the potential for antigenic change of EV-A71, we compared the sequences of two antigenically diverse genotype B4 and B5 strains of EV-A71 and identified substitutions at residues 98, 145, and 164 in the VP1 capsid protein as antigenic determinants. To examine the effects of these three substitutions on antigenicity, we constructed a series of recombinant viruses containing different mutation combinations at these three residues with a reverse genetics system and then investigated the molecular basis of antigenic changes with antigenic cartography. We found that a novel EV-A71 mutant, containing lysine, glutamine, and glutamic acid at the respective residues 98, 145, and 164 in the VP1 capsid protein, exhibited neutralization reduction against patients' antisera and substantially increased virus binding ability to human cells. These observations indicated that this low-neutralization-reactive EV-A71 VP1-98K/145Q/164E mutant potentially increases viral binding ability and that surveillance studies should look out for these mutants, which could compromise vaccine efficacy. IMPORTANCE: Emerging and reemerging EV-A71 viruses can cause severe neurological etiology, primarily affecting children, especially around Asia-Pacific countries. We identified a set of mutations in EV-A71 that both reduced neutralization activity against humoral immunity in antisera of patients and healthy adults and greatly increased the viral binding ability to cells. These findings provide important insights for EV-A71 antigenic determinants and emphasize the importance of continuous surveillance, especially after EV-A71 vaccination programs begin.

Norepinephrine and Epinephrine Enhanced the Infectivity of Enterovirus 71.

BACKGROUND: Enterovirus 71 (EV71) infections may be associated with neurological complications, including brainstem encephalitis (BE). Severe EV71 BE may be complicated with autonomic nervous system (ANS) dysregulation and/or pulmonary edema (PE). ANS dysregulation is related to the overactivation of the sympathetic nervous system, which results from catecholamine release. OBJECTIVE: The aims of this study were to explore the effects of catecholamines on severe EV71 infection and to investigate the changes in the percentages of EV71-infected cells, virus titer, and cytokine production on the involvement of catecholamines. STUDY DESIGN: Plasma levels of norepinephrine (NE) and epinephrine (EP) in EV71-infected patients were measured using an enzyme-linked immunoassay. The expression of adrenergic receptors (ADRs) on RD, A549, SK-N-SH, THP-1, Jurkat and human peripheral blood mononuclear cells (hPBMCs) were detected using flow cytometry. The percentages of EV71-infected cells, virus titer, and cytokine production were investigated after treatment with NE and EP. RESULTS: The plasma levels of NE and EP were significantly higher in EV71-infected patients with ANS dysregulation and PE than in controls. Both α1A- and ß2-ADRs were expressed on A549, RD, SK-N-SH, HL-60, THP-1, Jurkat cells and hPBMCs. NE treatment elevated the percentages of EV71-infected cells to 62.9% and 22.7% in THP-1 and Jurkat cells, respectively. Via treatment with EP, the percentages of EV71-infected cells were increased to 64.6% and 26.9% in THP-1 and Jurkat cells. The percentage of EV71-infected cells increased upon NE or EP treatment while the α- and ß-blockers reduced the percentages of EV71-infected cells with NE or EP treatment. At least two-fold increase in virus titer was observed in EV71-infected A549, SK-N-SH and hPBMCs after treatment with NE or EP. IL-6 production was enhanced in EV71-infected hPBMCs at a concentration of 102 pg/mL NE. CONCLUSION: The plasma levels of NE and EP elevated in EV71-infected patients with ANS dysregulation and PE. Both NE and EP enhanced the percentages of infected cells and virus titers in EV71 infection in vitro. NE and EP may play a role in the pathogenesis of EV71 BE complicated with ANS dysregulation and PE.

The clinical correlation of regulatory T cells and cyclic adenosine monophosphate in enterovirus 71 infection.

BACKGROUND: Brainstem encephalitis (BE) and pulmonary edema (PE) are notable complications of enterovirus 71 (EV71) infection. OBJECTIVE: This study investigated the immunoregulatory characterizations of EV71 neurological complications by disease severity and milrinone treatment. STUDY DESIGN: Patients <18 years with virologically confirmed EV71 infections were enrolled and divided into 2 groups: the hand, foot, and mouth disease (HFMD) or BE group, and the autonomic nervous system (ANS) dysregulation or PE group. Cytokine and cyclic adenosine monophosphate (cAMP) levels, and the regulatory T cell (Tregs) profiles of the patients were determined. RESULTS: Patients with ANS dysregulation or PE exhibited significantly low frequency of CD4(+)CD25(+)Foxp3+ and CD4(+)Foxp3(+) T cells compared with patients with HFMD or BE. The expression frequency of CD4-CD8- was also significantly decreased in patients with ANS dysregulation or PE. Among patients with ANS dysregulation or PE, the expression frequency of CD4+Foxp3+ increased markedly after milrinone treatment, and was associated with reduction of plasma levels IL-6, IL-8 and IL-10. Plasma concentrations of cAMP were significantly decreased in patients with ANS dysregulation or PE compared with patients with HFMD or BE; however, cAMP levels increased after milrinone treatment. CONCLUSIONS: These findings suggested decreased different regulatory T populations and cAMP expression correlate with increased EV71 disease severity. Improved outcome after milrinone treatment may associate with increased regulatory T populations, cAMP expression and modulation of cytokines levels.

High-incidence of human adenoviral co-infections in taiwan.

BACKGROUND: Respiratory infections caused by adenovirus (HAdV) are common year round. Recently, a significant increase of adenoviral infections was observed in Taiwan. OBJECTIVE: To understand the prevalence and molecular epidemiology of respiratory adenovirus circulating in Taiwan for the past decade. STUDY DESIGN: One hundred and twenty-six human adenoviruses, isolated between 2002 to 2011, were characterized via DNA sequencing of the hexon and fiber genes. The nucleotide sequences were then compared by phylogenetic analysis. RESULTS: HAdV-B3 accounted for 64.3% (81/126) and peaked almost every year, whereas the sequences of hexon and fiber genes of HAdV-B3 were highly conserved in different years. A high incidence of co-infection of adenoviruses was observed (19.0%, 24/126); HAdV-B3 co-infected with HAdV-C2 was the most common combination (58.3%, 14/24). An additional interesting finding of repeated infection was noted in 10 children, all of whom showed first infection with adenovirus species HAdV-C, followed by species HAdV-B or HAdV-E. CONCLUSIONS: HAdV-B3 was the predominant type of respiratory adenovirus circulating in Taiwan over the past ten years. This merits further attention for vaccine development. Furthermore, the observed high-incidence of adenoviral co-infections along with repeated infections found in our study provides important epidemiological insights into adenovirus infections.

Developing a semi-quantitative occupational risk prediction model for chemical exposures and its application to a national chemical exposure databank.

In this study, a semi-quantitative occupational chemical exposure risk prediction model, based on the calculation of exposure hazard indexes, was proposed, corrected, and applied to a national chemical exposure databank. The model comprises one factor used to describe toxicity (i.e., the toxicity index), and two factors used to reflect the exposure potential (i.e., the exposure index and protection deficiency index) of workers exposed to chemicals. An expert system was used to correct the above proposed model. By applying the corrected model to data obtained from a national occupational chemical hazard survey program, chemical exposure risks of various manufacturing industries were determined and a national control strategy for the abatement of occupational chemical exposures was proposed. The results of the present study would provide useful information for governmental agencies to allocate their limited resources effectively for reducing chemical exposures of workers.

Hepatic damage caused by coxsackievirus B3 is dependent on age-related tissue tropisms associated with the coxsackievirus-adenovirus receptor.

Coxsackievirus B (CVB) and enterovirus 71 (EV71) are important causes of severe enteroviral diseases in neonates or young children in Taiwan. CVB can cause fulminant hepatitis, myocarditis or meningoencephalitis. This study was designed to explore the role of coxsackievirus-adenovirus receptor (CAR) in the pathogenesis of CVB3-infected hepatocytes via in vitro and mice studies. CVB3 (CVB3/2630) was isolated from liver tissue of a neonate with fulminant hepatitis. Cell lines A549, HeLa, HEp2 and Huh-7 were maintained in Dulbecco's modified Eagle's medium. Mice progeny 1 or 7 days old were used in the experiments. Viremia was noted in 7-day-old ICR mice 2 h after intraperitoneal injection. The highest viral titers were detected in blood, liver and spleen. Histopathological studies of the liver demonstrated polymorphonuclear cell infiltration, massive hepatic cell necrosis and apoptosis. CAR was expressed more in liver than in other tissues. Expression of CAR decreased with mouse age. Anti-CAR monoclonal antibody prevented infection of Huh-7 cells from CVB3. Furthermore, anti-CAR monoclonal antibody pretreatment can reduce mortality and decrease the level of liver enzymes in CVB3-infected mice. These findings indicate that CAR plays an important role in the initiation of CVB infections and is closely associated with hepatotropism and age-specific susceptibility.

The regulatory T cells in anti-influenza antibody response post influenza vaccination.

The efficacy and effectiveness of influenza vaccines depend primarily on the vaccine recipient and the virus similarity to the endemic virus. Regulatory T cells (Tregs) and cytokines are known to restrict immune responses against viral infections. We conducted this study to explore the role of Tregs, cytokines, and antibody production after influenza vaccination. The whole blood was collected from healthy subjects (n = 36) before and two weeks after influenza vaccine immunization for two or three consecutive years. The cell surface markers, intracellular staining of Foxp3(+) Tregs, and Th1/Th2 cytokines were determined. The antibody titer was detected using the hemagglutination inhibition test. The CD3(+), CD127(+), CD4(+)CD25(+) and CD4(+)Foxp3(+) cells were increased significantly post vaccination. The plasma level of the transforming growth factor (TGF-ß), but not interleukin (IL)-2, IL-4, IL-5, IL-10, IFN-γ, TNF-α, was also found to increase significantly after vaccination. We further correlated the cytokine fold-increases with the anti-influenza antibody titer for individual post vaccination. It was found that the IL-10 level after vaccination correlated with the fold-increases of anti-H1N1, anti-H3N2, anti-B/Yamagata, and anti-B/Victoria antibodies. But, a negative relationship occurs between the TGF-ß level and fold-increases of anti-H1N1, anti-H3N2, anti-B/Yamagata, and anti-B/Victoria antibodies post vaccination. Treg cells and TGF-ß seem to participate in the downregulation of the anti-influenza antibody response post influenza vaccination. Alteration of Treg activity might enhance influenza vaccine antibody responses and efficacy.

A pilot study for determining the optimal operation condition for simultaneously controlling the emissions of PCDD/Fs and PAHs from the iron ore sintering process.

In this study, the cost-benefit analysis technique was developed and incorporated into the Taguchi experimental design to determine the optimal operation combination for the purpose of providing a technique solution for controlling both emissions of PCDD/Fs and PAHs, and increasing both the sinter productivity (SP) and sinter strength (SS) simultaneously. Four operating parameters, including the water content, suction pressure, bed height, and type of hearth layer, were selected and all experimental campaigns were conducted on a pilot-scale sinter pot to simulate various sintering operating conditions of a real-scale sinter plant. The resultant optimal combination could reduce the total carcinogenic emissions arising from both emissions of PCDD/Fs and PAHs by 49.8%, and increase the sinter benefit associated with the increase in both SP and SS by 10.1%, as in comparison with the operation condition currently used in the real plant. The ANOVA results indicate that the suction pressure was the most dominant parameter in determining the optimal operation combination. The above result was theoretically plausible since the higher suction pressure provided more oxygen contents leading to the decrease in both PCDD/F and PAH emissions. But it should be noted that the results obtained from the present study were based on pilot scale experiments, conducting confirmation tests in a real scale plant are still necessary in the future.

Clinical and laboratory characteristics of human immunodeficiency virus-infected adolescents: experience from a single medical center.

BACKGROUND: Recently, the proportion of adolescents diagnosed with human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome (AIDS) has increased. The aim of this study is to evaluate the clinical and laboratory characteristics of HIV-infected adolescents in southern Taiwan. METHODS: From June 1997 to December 2010, a total of 40 HIV-infected adolescents who sought medical care in a university hospital in southern Taiwan were enrolled in the study. They were classified into three HIV at-risk groups, men who have sex with men (MSM), heterosexuals, and intravenous drug users (IDUs). Clinical and laboratory data were obtained from medical records. RESULTS: The median age of the 40 HIV-infected adolescents was 19 years. The HIV at-risk groups were MSM (22/40, 55%), heterosexuals (7/40, 17.5%), IDUs (5/40, 12.5%), and unknown (6/40, 15%). The initial median CD4 count and log plasma HIV viral load were 318 cells/mm(3) and 4.61, respectively. The seroprevalence of anti-HAV, anti-HBc, anti-HCV antibodies and HBsAg was 5.3%, 26.1%, 13% and 13%, respectively. Among 17 adolescents who had regular follow-ups more than twice, 7 (41.2%) had a concurrent sexually transmitted disease (STD). The most common STD was genital warts (41.2%) followed by syphilis (11.8%). Among 7 patients who received highly active antiretroviral agents (HAART) for more than 12 months, 5 (71.4%) had sustained virologic suppression. CONCLUSION: MSM are the largest risk group in HIV-infected adolescents in southern Taiwan and are characterized by a high prevalence of anogenital warts and low seroprevalence of anti-HAV.