Bacterial infection in patients with visceral leishmaniasis

In an analysis of 63 hospitalized cases with visceral leishmaniasis, the clinical or post-mortem diagnosis of bacterial infection was performed in 33; 13 (39.3%) patients had respiratory infection, 4 (12.1%) had skin infection, 4 had urinary tract infection, 3 (9.0%) showed ear infection and 2 (6.6%) had infection of the oral cavity. It is worth mentioning that in 7 (21%) cases there was infection in multiple sites. Gram positive and/or Gram negative organisms were isolated from 10 patients. In only two (autopsied) cases, infection with less common organisms was recorded, one with disseminated candidiasis and another with disseminated tuberculosis. Death occurred in 9 of the 63 cases, and in 8 of these, concomitant bacterial infection of importance was documented. Patients who had serum globulins lower than 4 g% had significantly more infection (p less than 0.05) than patients with globulin levels higher than 4 g%; there was no significant difference when the number of leucocytes and neutrophils in patients with associated infection was compared with those in patients without bacterial infection. The present study demonstrates that bacterial infection frequently occurs in patients with visceral leishmaniasis, and indicates an unfavourable prognosis. Even though the mechanism of increased susceptibility to infection in this condition was unclear, the widespread range of infections and of infective agents, suggests a multifactorial process.     

以儿童呼吸道感染为主的非典型EBV感染报道

目的报道儿童EBV感染所致的临床疾病谱与年龄特点,以进一步提高对EBV感染诊治水平.方法回顾性分析了EBV-VCA-IgM或EBV-DNA-PCR诊断的690例儿童EBV感染的疾病分布和年龄分布特点.结果EBV感染儿童非典型传染性单核细胞增多症患儿422例,占61.16%,非典型EBV感染268例,占38.84%.非典型EBV感染中以呼吸道感染最为多见,为191例,占非典型EBV感染的71.27%.其他为皮炎或口炎、血小板减少性紫癜、腹泻病、川畸病、肠系膜或颈淋巴结炎、肾炎或肾病和CNS感染等.EBV感染致传染性单核细胞增多症和呼吸道感染在各年龄组的分布差异无显著性,EBV感染男女比为1.79：1.结论儿童EBV感染所致疾病多样,累及系统多,非典型表现以呼吸道感染为主.传染性单核细胞增多症和呼吸道感染在各年龄组间差异无显著性.     

Hymenolepis muris-sylvaticae and H. microstoma: immunological cross-reaction in mice

A primary infection with Hymenolepis microstoma strongly protects against cross-infection with H. muris-sylvaticae and also against secondary infection with H. microstoma in NMRI mice, resulting in an accelerated loss of worms and a weight reduction of the remaining worms. A primary infection with H. muris-sylvaticae causes an accelerated rejection of secondary infection with H. muris-sylvaticae but it has no effect on cross-infection with H. microstoma, neither with regard to worm recovery nor with regard to worm biomass. Determinations by enzyme-linked immunosorbent assay of antibody concentrations in the mouse sera revealed that: (1) the antibody response evoked by H. microstoma infection is much greater than by H. muris-sylvaticae infection; (2) a cross-infection with H. muris-sylvaticae boosts the antibody response evoked by H. microstoma infection; (3) H. microstoma antigen can be used to measure antibody concentration against both H. microstoma and H. muris-sylvaticae; and (4) although H. muris-sylvaticae is rejected faster in a cross-infection (i.e., after a primary H. microstoma infection) than in a secondary infection (i.e., after a primary H. muris-sylvaticae infection), antibodies evoked by the primary H. microstoma infection show little cross-reaction with H. muris-sylvaticae antigen. This suggests that it is doubtful whether serum antibodies are the direct effectors in worm rejection.     

Effect of antiviral treatment with entecavir on age- and dose-related outcomes of duck hepatitis B virus infection

Entecavir (ETV), a potent inhibitor of the hepadnaviral polymerases, prevented the development of persistent infection when administered in the early stages of duck hepatitis B virus (DHBV) infection. In a preliminary experiment, ETV treatment commenced 24 h before infection showed no significant advantage over simultaneous ETV treatment and infection. In two further experiments 14-day-old ducks were inoculated with DHBV-positive serum containing 10(4), 10(6), 10(8), or 5 x 10(8) viral genomes (vge) and were treated orally with 1.0 mg/kg of body weight/day of ETV for 14 or 49 days. A relationship between virus dose and infection outcome was seen: non-ETV-treated ducks inoculated with 10(4) vge had transient infection, while ducks inoculated with higher doses developed persistent infection. ETV treatment for 49 days did not prevent initial infection of the liver but restricted the spread of infection more than approximately 1,000-fold, a difference which persisted throughout treatment and for up to 49 days after withdrawal. Ultimately, three of seven ETV-treated ducks resolved their DHBV infection, while the remaining ducks developed viremia and persistent infection after a lag period of at least 63 days. ETV treatment for 14 days also restricted the spread of infection, leading to marked and sustained reductions in the number of DHBV-positive hepatocytes in 7 out of 10 ducks. In conclusion, short-term suppression with ETV provides opportunity for the immune response to successfully control DHBV infection. Since DHBV infection of ducks provides a good model system for HBV infection in humans, it seems likely that ETV may be useful in postexposure therapy for HBV infection aimed at preventing the development of persistent infection.     

Phospholipid Synthesis in Escherichia coli Infected with T4 Bacteriophages

After infection of Escherichia coli with T4 phage, phospholipid synthesis continued but at a reduced rate. The same phospholipid components were synthesized as in uninfected cells; however, the relative rates of (32)P(i) incorporation into phosphatidylglycerol (PG) and phosphatidylethanolamine (PE) were altered. This alteration was most pronounced during the first 10 min after infection. Under these conditions, the isotope incorporated into PG equaled or exceeded that found in PG from uninfected cells. Chloramphenicol (CM) added before, but not 5 min after, infection inhibited the relative increase in PG synthesis, and CM added at different times after infection indicated that a protein synthesized between 3 and 6 min was required for this change to occur. Supplies of exogenous l-serine or l-alpha-glycerol-P failed to affect the relative rates of (32)P(i) incorporation into PG and PE by infected or uninfected cells. Phospholipid synthesis was somewhat higher after infection with T4rII mutants than after infection with wild-type phage. After infection with these mutants or several amber mutants, the relative synthesis of PG and PE was characteristic of T4r(+)-infected cells. The phospholipid synthesized after infection did not rapidly turn over, but infection accelerated the loss of PG synthesized prior to infection.     

Delta Hepatitis in Denver

The prevalence of hepatitis D virus (HDV) infection in patients with hepatitis B virus (HBV) infection in the mid-United States is not well defined. We tested 65 patients seen between 1983 and 1986 with HBV infection in Denver for evidence of coexisting HDV infection. Five patients had anti-delta (δ) antibody. The prevalence of HDV infection was higher in patients with chronic hepatitis B (4/37) than in patients with acute hepatitis B (1/28). The prevalence of HDV infection in male homosexuals (3/32) was similar to reported figures, but the incidence of δ-infection in intravenous drug users in Denver was usually low (1/16). In comparison to Los Angeles, New York, southern Italy, and Sweden, Denver appears to have a low incidence of HDV infection, which probably reflects its low prevalence in the drug-using population.     

Prevalence of rat virus infection in progeny of acutely or persistently infected pregnant rats

Infant rats are susceptible to persistent rat virus (RV) infection, but risk of persistent infection after prenatal exposure to virus is unclear. We examined this aspect of RV infection in the progeny of dams inoculated with virus during or prior to pregnancy. Sprague-Dawley (SD) dams were infected during pregnancy (gestation day 9) by oronasal inoculation with 10(5) TCID50 of the UMass strain of RV. SD rats were infected prior to pregnancy by oronasal inoculation of two-day-old females with 10(2) TCID50 of RV-UMass, which induced persistent infection. They were mated to non-immune males after reaching sexual maturity. Rats were assessed for RV infection by virus isolation, in situ hybridization, contact transmission, or serologic testing. The progeny of dams inoculated with virus during gestation had high prevalence of infection through postpartum week 9 (9 of 12 rats were virus positive at week 3, and 7 of 10 were virus positive at week 9). Additionally, 2 of 10 rats were virus positive at least through postpartum week 15. The progeny from persistently infected, seropositive dams had no evidence of infection and did not transmit infection to contact sentinels. However, 12 dams were virus positive at necropsy and 9 had transmitted infection to their breeding partners. These results indicate that prenatal infection in non-immune dams can lead to RV persistence in their progeny. By contrast, the progeny of persistently infected dams are protected from infection, presumably by maternal antibody, although their dams can transmit infection to their breeding partners.     

The infected or exposed breast implant: management and treatment strategies

Among the potential complications associated with the use of breast implants are the risks of periprosthetic infection and device extrusion. There is little published information about the effective management of these situations. Conservative recommendations include antibiotic therapy and removal of the implant until resolution of the infection or until the wound has healed. A retrospective review identified patients with periprosthetic infection or threatened or actual device exposure treated by the senior author. Twenty-four patients encompassing 26 affected prostheses were available for review and were classified into seven groups based on initial presentation as follows: group 1, mild infection (n = 8); group 2, severe infection (n = 4); group 3, threatened exposure without infection (n = 3); group 4, threatened exposure with mild infection (n = 3); group 5, threatened exposure with severe infection (n = 1); group 6, actual exposure without clinical infection (n = 5); and group 7, actual exposure with infection (n = 2). To salvage the prosthesis in these patients, various treatment strategies were utilized. All patients with a suspected infection or device exposure were started immediately on appropriate antibiotic therapy (oral antibiotics for mild infections and parenteral antibiotics for severe infections). Salvage methods included one or more of the following: antibiotic therapy, débridement, curettage, pulse lavage, capsulectomy, device exchange, primary closure, and/or flap coverage. Twenty (76.9 percent) of 26 threatened implants with infection or threatened or actual prosthesis exposure were salvaged after aggressive intervention. The presence of severe infection adversely affected the salvage rate in this series. A statistically significant difference exists among those patients without infection or with mild infection only (groups 1, 3, 4, and 6); successful salvage was achieved in 18 (94.7 percent) of 19 patients, whereas only two of seven of those implants with severe infection (groups 2, 5, and 7) were salvaged (p = 0.0017). Ten (90.9 percent) of 11 devices with threatened or actual exposure, not complicated by severe infection (groups 3, 4, and 6), were salvaged. Several treatment strategies were developed for periprosthetic infection and for threatened or actual implant exposure. Patients with infection were placed on oral or intravenous antibiotics; those who responded completely required no further treatment. For persistent mild infection or threatened or actual exposure, operative intervention was required, including some or all of the following steps: implant removal, pocket curettage, partial or total capsulectomy, débridement, site change, placement of a new implant, and/or flap coverage; the menu of options varied with the precise circumstances. No immediate salvage was attempted in five cases, due to either severe infection, nonresponding infection with gross purulence, marginal tissues, or lack of options for healthy tissue coverage. Based on the authors' experience, salvage attempts for periprosthetic infection and prosthesis exposure may be successful, except in cases of overwhelming infection or deficient soft-tissue coverage. Although an attempt at implant salvage may be offered to a patient, device removal and delayed reinsertion will always remain a more conservative and predictable option.     

Effects of mannan oligosaccharide on the physiological responses,HSP70 gene expression and disease resistance of Allogynogenetic crucian carp (Carassius auratus gibelio) under Aeromonas hydrophila infection

We evaluated the effect of dietary supplementation with mannan oligosaccharide (MOS) on the resistance to Aeromonas hydrophi1a infection in Allogynogenetic crucian carp. The fish were randomly divided into five groups: a control group was fed with basal diet, and four treatment groups fed with basal diet supplemented with 60, 120, 240, 480 mg/kg MOS for 10 weeks, respectively. We then challenged the fish with A. hydrophi1a and recorded the mortality and the changes in serum cortisol, T3, T4, lysozyme, alkaline phosphatase (ALP), globin and hepatic total anti-oxidative capacity, superoxide dismutase (SOD), malondialdehyde (MDA) and the relative expression of heat shock protein 70 (HSP70) mRNA for a period of 7 d. Supplementation with 240 mg/kg MOS significantly increased serum ALP activity before infection, 1d and 2d after infection, serum globin concentration prior to infection, 1d and 7d after infection, serum lysozyme activity at 2d after infection, T3 concentration at 2d after infection, hepatic total anti-oxidative capacity prior to infection, hepatic SOD activity at 7d after infection and reduced serum cortisol concentration at 2d after infection, hepatic malondialdehyde content at 1d and 2d after infection. Supplementation with 480 mg/kg MOS significantly increased serum ALP activity before infection, 1d and 2d after infection, T3 content 1d after infection, T4 content prior infection and 7d after infection, serum globin concentration prior to infection, 1d and 7d after infection, serum lysozyme activity prior infection and 1d after infection, serum total anti-oxidative capacity prior to infection and 7d after infection, hepatic SOD activity at 7d after infection and the relative level of hepatic HSP70 mRNA at 2d and 7d after infection, had decreased levels of serum cortisol concentration before the infection, at 2d after infection, T4 concentration at 1d and 2d after infection, hepatic malondialdehyde content at 1d and 2d after infection. Mortality was significantly lower in the group of 240 and 480 mg/kg MOS than the control. Our results suggest that ingestion of a basal diet supplemented with 240–480 mg/kg MOS can enhance resistance against pathogenic infections in Allogynogenetic crucian carp.     

Sustained Hyperresponsiveness of Dendritic Cells Is Associated with Spontaneous Resolution of Acute Hepatitis C

Some studies have reported that dendritic cells (DCs) may be dysfunctional in a subset of patients with chronic hepatitis C virus (HCV) infection. However, the function of DCs during acute HCV infection and their role in determining infectious outcome remain elusive. Here, we examined the phenotype and function of myeloid DCs (mDCs) and plasmacytoid DCs (pDCs) during acute HCV infection. Three groups of injection drug users (IDUs) at high risk of HCV infection were studied: an uninfected group, a group with acute HCV infection with spontaneous resolution, and a group with acute infection with chronic evolution. We examined the frequency, maturation status, and cytokine production capacity of DCs in response to the Toll-like receptor 4 (TLR4) and TLR7/8 ligands lipopolysaccharide (LPS) and single-stranded RNA (ssRNA), respectively. Several observations could distinguish HCV-negative IDUs and acute HCV resolvers from patients with acute infection with chronic evolution. First, we observed a decrease in the frequency of mature CD86⁺, programmed death-1 receptor ligand-positive (PDL1⁺), and PDL2⁺ pDCs. This phenotype was associated with the increased sensitivity of pDCs from resolvers and HCV-negative IDUs versus the group with acute infection with chronic evolution to ssRNA stimulation in vitro. Second, LPS-stimulated mDCs from resolvers and HCV-negative IDUs produced higher levels of cytokines than mDCs from the group with acute infection with chronic evolution. Third, mDCs from all patients with acute HCV infection, irrespective of their outcomes, produced higher levels of cytokines during the early acute phase in response to ssRNA than mDCs from healthy controls. However, this hyperresponsiveness was sustained only in spontaneous resolvers. Altogether, our results suggest that the immature pDC phenotype and sustained pDC and mDC hyperresponsiveness are associated with spontaneous resolution of acute HCV infection.     

A recombinant vaccinia virus encoding inducible nitric oxide synthase is attenuated in vivo.

To investigate the role of nitric oxide during vaccinia virus (VV) infection of mice, a recombinant VV encoding the inducible nitric oxide synthase (iNOS) gene (VV-HA-iNOS) was constructed. Following infection of immunocompromised or immunocompetent mice, the virus was highly attenuated compared with a control recombinant VV. Athymic and sublethally irradiated mice survived infection with 10(7) PFU of VV-HA-iNOS, a dose that resulted in uniform mortality in mice infected with the control recombinant VV. Attenuated virus growth was evident as early as 24 h following infection, suggesting that NO had direct antiviral activity. We have previously shown that treatment of mice with the inhibitor of NO production N(G)-methyl-L-arginine did not influence the course of VV infection in mice. The present study has indicated that NO can potentially exert an antiviral effect during murine VV infection. We propose that during VV infection, nitric oxide production contributes to the control of virus growth, but that in its absence, other antiviral mechanisms are sufficient to mediate fully effective virus clearance.     

Prevalence of hepatitis B virus infections in nonhuman primates

The aim of this study was to determine the prevalence of hepatitis B virus (HBV) infection in nonhuman primates. Serum samples from Europe, Thailand and Vietnam were analyzed. Sera obtained from 262 apes and 454 monkeys were tested for HBV infection serologically and for HBV DNA using nested PCR (nPCR). A total number of 198 ape sera and all but one (Cercopithecus aethiops) of the 4543 monkey sera had no serological signs of HBV infection. Among the 64 of 262 (24.4%) seropositive ape sera, we found, as in humans, different stages of HBV infection: very early HBV infection, active infection with high level of infectivity, virus carriers with low infectivity, and passed HBV infection. In the cases with passed infection, 47.8% harbored HBV DNA in the presence of protective antibodies to the HBV surface antigen (HBsAb). This indicates HBV persistence in apes despite immune control. In contrast to apes, in monkeys HBV infection is a very rare event.     

Opsonization of HIV with complement enhances infection of dendritic cells and viral transfer to CD4 T cells in a CR3 and DC-SIGN-dependent manner

In the present study, we demonstrated that opsonization of primary HIV-1 with human complement enhances infection of immature monocyte-derived dendritic cells (iDC) and transmission in trans of HIV to autologous CD4(+) T lymphocytes. Infection of iDC by opsonized primary R5- and X4-tropic HIV was increased 3- to 5-fold as compared with infection by the corresponding unopsonized HIV. Enhancement of infection was dependent on CR3 as demonstrated by inhibition induced by blocking Abs. The interaction of HIV with CCR5 and CXCR4 on iDC was affected by opsonization. Indeed, stromal-derived factor-1 was more efficient in inhibiting infection of iDC with opsonized R5-tropic HIV-1(BaL) (45%) than with heat-inactivated complement opsonized virus and similarly RANTES inhibited more efficiently infection of iDC with opsonized X4-tropic HIV-1(NDK) (42%) than with heat-inactivated complement opsonized virus. We also showed that attachment of complement-opsonized virus to DC-specific ICAM-grabbing nonintegrin (DC-SIGN) molecule on iDC and HeLa DC-SIGN(+) CR3(-) cells was 46% and 50% higher compared with heat-inactivated complement opsonized virus, respectively. Hence, Abs to DC-SIGN suppressed up to 80% and 60% the binding of opsonized virus to HeLa cells and iDC, respectively. Furthermore, Abs to DC-SIGN inhibited up to 70% of the infection of iDC and up to 65% of infection in trans of autologous lymphocytes with opsonized virus. These results further demonstrated the role of DC-SIGN in complement opsonized virus uptake and infection. Thus, the virus uses complement to its advantage to facilitate early steps leading to infection following mucosal transmission of HIV.     

Modeling the population dynamics of baculovirus-infected insect cells: Optimizing infection strategies for enhanced recombinant protein yields

The insect cell-baculovirus model presented here is capable of simulating cell population dynamics, extracellular virion densities, and heterologous product titers in reasonable agreement with experimental data for a wide rang of multiplicities of infection (MOI) and times of infection. The model accounts for the infection of a single cell by multiple virions and the consequences on the time course of infection. The probability of infection by more than one virion was approximated using the Poisson distribution, which proved to be a refinement over second-order kinetics. The model tracks initiation and duration of important events in the progression of infected cell development (virus replication, recombinant protein synthesis, and cell lysis) for subpopulations delineated by the time and extent of their initial infection. The model suggests infection strategies, weighing the importance of MOI and infection time. Maximum product titers result from infection in the early exponential growth phase with low MOI.     

2006～2010年泌尿生殖道炎症患者支原体感染率检测与耐药性分析

目的 了解杭州市萧山区2006～ 2010年泌尿生殖道炎症患者支原体感染及耐药情况.方法 对4 023例泌尿生殖道炎症患者用支原体鉴定及药敏试剂盒进行支原体培养及药敏试验.结果 支原体总检出率为48.1％,女性检出率51.2％明显高于男性41.8％ (P ＜0.05).支原体培养阳性患者中Uu单独感染1701例(88.0％),Mh单独感染57例(2.9％),Uu+ Mh混合感染176例(9.1％),Uu单独感染明显高于Mh单独感染和Uu+ Mh混合感染(P＜0.05).5年间支原体阳性检出率从2006年的39.4％到2010年的58.1％逐年增高,感染模式观察期内无明显变化.支原体对交沙霉素、原始霉素和强力霉素均敏感(敏感率≥91.4％),对四环素、红霉素、氧氟沙星和环丙沙星的耐药率高,均大于50％.比较2006年至2010年各种支原体对9种药物的耐药率,除四环素外耐药率呈不同程度上升,四环素耐药率2007年和2008年较高,后逐年下降,2010年为53.5％.混合感染总体耐药率比Uu或Mh单独感染耐药率高.结论 泌尿生殖道炎症患者支原体感染Uu比较常见,且女性检出率显著高于男性.临床分离支原体大多具有多重耐药性,临床治疗需根据药敏结果加以选择.     

The cytokine balance in the maintenance of a persistent infection with Salmonella enterica serovar Typhimurium in mice

ClpXP, serine protease-disrupted mutant of Salmonella enterica serovar Typhimurium chi3306 exhibits attenuated but persistent infection in mice. During infection with S. enterica serovar Typhimurium ClpXP-disrupted mutant, gamma interferon (IFN-gamma) produced by CD4+ cells was up-regulated on day 10 and tumor necrosis factor-alpha (TNF-alpha) produced by CD8+ cells was up-regulated on day 30 after infection. Treatment of monoclonal antibodies against cytokines showed that IFN-gamma and interleukin 10 (IL-10) were involved in maintenance of growth of S. Typhimurium mutant on day 10 after infection, and IFN-gamma, TNF-alpha and transforming growth factor-beta (TGF-beta) were involved in maintenance of growth of this bacterium on day 30 after infection. During persistent infection of S. Typhimurium mutant, IFN-gamma, TNF-alpha, IL-10 and TGF-beta may play different roles to maintain the persistent infection. The cytokine balance might be important in persistent infection with ClpXP-disrupted S. enterica serovar Typhimurium.     

Immunologic hypo- or non-responder in natural dengue virus infection

Serologically defined primary dengue virus infection and/or subsequent homologous serotype infection is known to be associated with less severe disease as compared with secondary subsequent heterologous serotype infection. In geographical locales of high dengue endemicity, almost all individuals in the population are infected at some point in time and should therefore are at high risk of secondary infection. Interestingly, dengue viremia in healthy blood donors whose sera apparently lack detectable levels of specific antibody to dengue viral antigens has been reported. The incidence rate of potential immunologic hypo- or non-responders following natural primary dengue virus infection in dengue endemic regions, who do become immune responders only after repeated exposure, has not been described. These are the patients who may be diagnosed as primary infection in the subsequent infection, but actually are secondary infection. This concept has important implications with regards to the hypothesis of immunological enhancement of dengue pathogenesis, which has largely been advanced based on empirical observations and/or from in vitro experimental assays. The fact that dengue naïve travelers can suffer from severe dengue upon primary exposure while visiting dengue endemic countries underscores one of the major problems in explaining the role of immune enhancement in the pathogenesis of severe dengue virus infection. This evidence suggests that the mechanism(s) leading to severe dengue may not be associated with pre-existing enhancing antibody. Consequently, we propose a new paradigm for dengue virus infection classification. These include a) patients with naïve primary infection, b) those that are serologically defined primary in dengue endemic zones and c) those who are serologically defined secondary dengue virus infection. We submit that clarity with regards to such definitions may help facilitate the delineation of the potential mechanisms of severe dengue virus infection.     

PCT、IL-6及CRP对新生儿宫内细菌感染的诊断价值

目的:探讨新生儿宫内细菌感染采用降钙素原(PCT)、白细胞介素-6(IL-6)、及C反应蛋白(CRP)诊断的临床价值。方法:根据感染结局将2013年3月~2014年9月在我院分娩且有宫内感染高危因素的179例新生儿分为感染组(34例)和无感染组(145例),检测两组的PCT、IL-6及CRP水平,并比较各项指标对宫内细菌感染的诊断价值。结果:感染组脐带血PCT、IL-6、CRP水平均高于无感染组,差异有统计学意义(P0.05)。感染组各单个指标阳性率、两指标联合的阳性率高于无感染组,差异均有统计学意义(P0.05),感染组中PCT、IL-6阳性率高于CRP,PCT+IL-6的阳性率高于PCT+CRP、IL-6+CRP,差异均有统计学意义(P0.05)。PCT+IL-6的灵敏度、准确率高于单个指标及其他两个指标联合检测的结果,差异有统计学意义(P0.05),各项指标检测的特异性比较,差异无统计学意义(P0.05)。结论:新生儿宫内感染采用脐带血PCT检测具有灵敏度高,特异性好的特点,联合IL-6检测是临床诊断新生儿宫内感染的最有效的方式。     

Expression of cytokines in bacterial and viral infections and their biochemical aspects

Cytokines are very important in the host defense system, and play a critical role in protection against bacterial and viral infections. Cytokines are also involved in the pathogenesis and development of symptoms in infections. In this article, Helicobacter pylori (H. pylori) infection as bacterial infection, and influenza virus infection, encephalomyocarditis virus (EMCV) infection, and herpes simplex virus (HSV) infection as viral infection are mentioned. In H. pylori infection, various chemokines, especially interleukin (IL)-8, induce inflammatory responses in the gastroduodenal mucosa. Furthermore, IL-6, IL-7, tumor necrosis factor (TNF)-alpha, and interferon (IFN)-gamma are involved in both protection and pathogenesis. In influenza virus infection, IFN-alpha/beta, IFN-gamma, and IL-6 play protective roles. In EMCV infection, IL-6 and TNF-alpha play important roles as a protective and exacerbative factor in acute myocarditis, respectively. Furthermore, in HSV infection, the production of inflammatory cytokines is closely correlated with the pathogenesis of herpetic keratitis, and IFN-gamma plays an important role in enhancing viral clearance from the cornea and trigeminal ganglions.     

Human Plasmacytoid Dendritic Cells Elicited Different Responses after Infection with Pathogenic and Nonpathogenic Junin Virus Strains

The arenavirus Junin virus (JUNV) is the etiologic agent of Argentine hemorrhagic fever. We characterized the JUNV infection of human peripheral blood-derived plasmacytoid dendritic cells (hpDC), demonstrating that hpDC are susceptible to infection with the C#1 strain (attenuated) and even more susceptible to infection with the P (virulent) JUNV strain. However, hpDC elicited different responses in terms of viability, activation, maturation, and cytokine expression after infection with both JUNV strains.