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Infection Worldwide (infection + worldwide)
Selected AbstractsIncreased liver mast cell recruitment in patients with chronic C virus-related hepatitis and histologically documented steatosisJOURNAL OF VIRAL HEPATITIS, Issue 8 2007B. Franceschini Summary., Hepatitis C virus (HCV) is still one of the major causes of chronic viral infection worldwide, and hepatic steatosis is a frequent pathological finding in patients with chronic HCV-related diseases. It is unclear whether the steatosis is associated with host factors or the virus itself, although a consistent relationship has been found between steatosis and a necro-inflammatory reaction with the increased secretion of immuno-regulators. A primary sources of inflammatory mediators are mast cells (MCs) bone marrow-derived cells that are detected in both normal and diseased livers. We determined MC density and correlated it with the fibrosis, inflammatory reaction and steatosis observed in the liver biopsies of patients affected by HCV with or without steatosis. All the histological features were assessed using a computer-aided image analysis system. There was a statistically significant difference in MC density between the HCV-infected patients with and without steatosis, with the lower mean value being detected in those without (P < 0.02). Furthermore, a nonstatistically significant difference in fibrosis and inflammation between the two patient groups was found. In conclusion, this is the first study showing a significant increase in MC density in the tissues of patients with chronic HCV infection and histologically documented steatosis. [source] Effect of Lactobacillus rhamnosus GR-1 and Lactobacillus reuteri RC-14 on the ability of Candida albicans to infect cells and induce inflammationMICROBIOLOGY AND IMMUNOLOGY, Issue 9 2009Rafael C.R. Martinez ABSTRACT Vulvovaginal candidiasis, a high prevailing infection worldwide, is mainly caused by Candida albicans. Probiotic Lactobacillus reuteri RC-14 and Lactobacillus rhamnosus GR-1 have been previously shown to be useful as adjuvants in the treatment of women with VVC. In order to demonstrate and better understand the anti- Candida activity of the probiotic microorganisms in an in vitro model simulating vaginal candidiasis, a human vaginal epithelial cell line (VK2/E6E7) was infected with C.albicans 3153a and then challenged with probiotic L. rhamnosus GR-1 and/or L. reuteri RC-14 or their respective CFS (alone or in combination). At each time point (0, 6, 12 and 24 hr), numbers of yeast, lactobacilli and viable VK2/E6E7 cells were determined and, at 0, 6 and 12 hr, the supernatants were measured for cytokine levels. We found that C. albicans induced a significant increase in IL-1, and IL-8 production by VK2/E6E7 cells. After lactobacilli challenge, epithelial cells did not alter IL-6, IL-1,, RANTES and VEGF levels. However, CFS from the probiotic microorganisms up-regulated IL-8 and IP-10 levels secreted by VK2/E6E7 cells infected with C. albicans. At 24 hr of co-incubation, L. reuteri RC-14 alone and in combination with L. rhamnosus GR-1 decreased the yeast population recoverable from the cells. In conclusion, L. reuteri RC-14 alone and together with L. rhamnosus GR-1 have the potential to inhibit the yeast growth and their CFS may up-regulate IL-8 and IP-10 secretion by VK2/E6E7 cells, which could possibly have played an important role in helping to clear VVC in vivo. [source] Human metapneumovirus and respiratory syncytial virus infections in older children with cystic fibrosisPEDIATRIC PULMONOLOGY, Issue 1 2007Daniel F. Garcia MD Abstract Background: Human metapneumovirus (hMPV) has been isolated from children with acute respiratory infection worldwide. Its epidemiology remains to be defined in children with cystic fibrosis (CF). We describe the epidemiology and clinical impact of hMPV in CF children and compared it to respiratory syncytial virus (RSV). Methods: CF children ages 7,18 years were studied prospectively during the 1998,1999 RSV season. Nasopharyngeal specimens were collected during acute respiratory illnesses and tested for respiratory viruses. Blood specimens were drawn early, mid, and end of the RSV season, and tested for serological evidence of hMPV and RSV infections. Rates of lower respiratory tract illnesses (LRTI) and hospitalizations for pulmonary exacerbations were compared during the time intervals they developed serological evidence of infection to their non-infection intervals. Results: Six of 44 CF children had a virus positive respiratory illness in 56 LTRI events and 18 hospitalizations. Serological evidence of hMPV and RSV infections occurred in 16 and 20 CF children, respectively; 8 had infections with both viruses. A greater proportion of CF children had ,1 LRTI during their infection intervals compared to their non-infection intervals (13/25 vs. 5/25; P,=,0.03). A trend for higher rates of LRTI was observed in the infection intervals compared to non-infection intervals (9.5,±,11.0 vs. 4.2,±,9.9 per 1,000 child-days; P,=,0.06), and it was significantly greater with a more conservative estimate (one event per child per interval; 7.4,±,7.7 vs. 2.6,±,5.4 per 1,000 child-days; P,,0.01). No differences in hospitalizations rates were detected. Conclusion: The infection rates and clinical impact observed for hMPV were comparable to that for RSV in CF children 7,18 years of age. Pediatr Pulmonol. 2007; 42:66,74. © 2006 Wiley-Liss, Inc. [source] Morphogenesis of hepatitis B virus and its subviral envelope particlesCELLULAR MICROBIOLOGY, Issue 11 2009Romuald Patient Summary After cell hijacking and intracellular amplification, non-lytic enveloped viruses are usually released from the infected cell by budding across internal membranes or through the plasma membrane. The enveloped human hepatitis B virus (HBV) is an example of virus using an intracellular compartment to form new virions. Four decades after its discovery, HBV is still the primary cause of death by cancer due to a viral infection worldwide. Despite numerous studies on HBV genome replication little is known about its morphogenesis process. In addition to viral neogenesis, the HBV envelope proteins have the capability without any other viral component to form empty subviral envelope particles (SVPs), which are secreted into the blood of infected patients. A better knowledge of this process may be critical for future antiviral strategies. Previous studies have speculated that the morphogenesis of HBV and its SVPs occur through the same mechanisms. However, recent data clearly suggest that two different processes, including constitutive Golgi pathway or cellular machinery that generates internal vesicles of multivesicular bodies (MVB), independently form these two viral entities. [source] Immunological response to cytomegalovirus in congenitally infected neonatesCLINICAL & EXPERIMENTAL IMMUNOLOGY, Issue 3 2007J. Hassan Summary Cytomegalovirus (CMV) is the most common cause of congenital infection worldwide and occurs as a result of transplacental transmission of the virus. The human neonate is highly susceptible to infection due to a combination of immaturity of the immune system and antigenic inexperience. This study uses the in vivo model of congenital CMV to examine both the humoral and cell-mediated immune responses in vertically infected neonates and their mothers. Ten pairs of matched neonates and their mothers were evaluated for specific IgM responses to three immunodominant CMV antigens: pp38 (pUL80a), pp52 (pUL44) and pp150 (pUL32). In contrast to conventional enzyme immunoassay (EIA) testing for CMV-specific IgM, which found five of the mothers and four of the neonates to be positive, Western immunoblotting showed all 10 adults and nine newborns to be positive. Eight mothers and nine newborns had serological evidence of primary infection. All neonates showed a response to pp38, an assembly protein, nine responded to the pp52 immediate early antigen but only four had reactivity to the pp150 tegument associated protein. Of the mothers, eight had pp38 reactivity, 10 showed a response to the pp52 antigen and seven to the pp150 antigen. T cell-mediated immunity was assessed by measuring cytokines using a multiplex microarray assay. Levels of interferon (IFN)-, were high in both groups [mean ± standard error of the mean (s.e.m.): neonates = 657 ± 238 pg/ml, mothers = 1072 ± 677 pg/ml, pNS]; however, neonates had significantly higher levels of interleukin (IL)-8 (316 ± 136 pg/ml versus 48 ± 28 pg/ml, P < 0·005). Similar levels of IL-2, IL-7, IL-10 and IL-12 were measured in both groups, but levels of IL-1,, IL-1,, IL-4, IL-6 and tumour necrosis factor (TNF)-, were either absent or low. In response to CMV, neonates and adults mount a predominant T helper 1 (Th1) response, as evidenced by the presence of IL-2, IL-8, IL-12 and IFN-, with concomitant lack of IL-4. These findings suggest that the neonate, when presented with infection in utero, is capable of mounting an individual response; however, the lower IFN-, and higher IL-8 levels suggest reduced immune responsiveness when compared to their adult counterparts. [source] | |||||||||||||