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Infection Group (infection + group)
Selected AbstractsGrowth of Frankia strains in leaf litter-amended soil and the rhizosphere of a nonactinorhizal plantFEMS MICROBIOLOGY ECOLOGY, Issue 1 2009Babur S. Mirza Abstract The ability of Frankia strains to grow in the rhizosphere of a nonactinorhizal plant, Betula pendula, in surrounding bulk soil and in soil amended with leaf litter was analyzed 6 weeks after inoculation of pure cultures by in situ hybridization. Growth responses were related to taxonomic position as determined by comparative sequence analysis of nifH gene fragments and of an actinomycetes-specific insertion in Domain III of the 23S rRNA gene. Phylogenetic analyses confirmed the basic classification of Frankia strains by host infection groups, and allowed a further differentiation of Frankia clusters within the Alnus host infection group. Except for Casuarina -infective Frankia strains, all other strains of the Alnus and the Elaeagnus host infection groups displayed growth in the rhizosphere of B. pendula, and none of them grew in the surrounding bulk soil that was characterized by a very low organic matter content. Only a small number of strains that all belonged to a distinct phylogenetic cluster within the Alnus host infection group grew in soil amended with ground leaf litter from B. pendula. These results demonstrate that saprotrophic growth of frankiae is a common trait for most members of the genus, and the supporting factors for growth (i.e. carbon utilization capabilities) varied with the host infection group and the phylogenetic affiliation of the strains. [source] Hepatitis B virus and HIV coinfection: relationship of different serological patterns to survival and liver diseaseHIV MEDICINE, Issue 5 2007MK Osborn Objectives Eighty per cent of HIV-positive patients show evidence of past or current infection with hepatitis B virus (HBV). The impact of chronic HBV infection or the presence of isolated HBV core antibody on survival in the era of highly active antiretroviral therapy (HAART) has not been well studied. Methods This retrospective analysis included patients from the HIV Atlanta Veterans Affairs Cohort Study (HAVACS). This cohort comprises 2818 HIV-positive patients followed since 1982. For this analysis, 1685 patients with available HBV serologies were included, based on laboratory records available since 1992. Adjusted survival analyses were performed for patients showing any of four serological patterns for HBV: (1) surface antigen positive (chronic HBV infection), (2) isolated core antibody, (3) surface antibody with or without core antibody (resolved/vaccinated) and (4) no HBV markers (negative group). Risk factors for liver disease were identified. Results A trend was seen for a lower survival rate from AIDS to death in the chronic HBV infection group compared with the negative group [hazard ratio (HR) 1.43; P=0.118]. The only independent predictor of lower survival rate was hepatitis C virus positivity (HR 1.62; P=0.008). Protective factors were use of HAART (HR 0.40; P=0.0003), use of lamivudine (HR 0.36; P<0.0001) and use of tenofovir (HR 0.23; P<0.0001). Survival from HIV diagnosis to death was not different among the HBV groups. Isolated core antibody patients did not have a lower survival rate compared with those with resolved HBV infection. Patients with chronic HBV infection were 3.5 times more likely to have liver disease than those with no HBV infection (P<0.02). Conclusions There is a trend towards a lower survival rate in patients with HIV and chronic HBV infection, but the difference did not reach statistical significance. The presence of isolated core antibody was not associated with a lower survival rate. [source] Elevated plasma osteopontin level is predictive of cirrhosis in patients with hepatitis B infectionINTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 7 2008L. Zhao Summary Background:, Osteopontin (OPN) was shown to play an important role in the pathogenesis of various inflammatory and fibrotic processes and elevated in fibrotic liver of mouse model. However, the significance of OPN in hepatitis B virus (HBV)-induced liver cirrhosis (LC) remains unclear and is therefore evaluated in this study. Methods:, Thirty-nine patients with HBV-induced LC, 30 patients with HBV infection but without cirrhosis, 11 patients with HBV-related hepatocellular carcinoma (HCC) and 14 additional healthy controls were enrolled in this study. Plasma levels of OPN were measured with enzyme-linked immunosorbent assay and the relationship between OPN and clinical parameters was evaluated. Results:, When compared to HBV infection group (median 2.16 ng/ml), plasma levels of OPN were significantly increased in cirrhosis (4.52 ng/ml, p < 0.001) and cancer group (13.38 ng/ml, p < 0.001). The OPN level was correlated with the severity of liver damage according to Child,Pugh classification (p = 0.003). It showed at least comparable sensitivity and specificity to predict cirrhosis as aspartate aminotransferase to platelet ratio index, a previously established non-invasive serum marker of cirrhosis. Conclusions:, These data suggest that OPN could be used to evaluate the existence of LC, as OPN has previously been reported to be increased in the HCC; this unique feature makes OPN a promising candidate for prediction biomarker in the long-time surveillance of patients with HBV infection to evaluate the risk of cirrhosis and cancer. [source] Relationship of in vivo and ex vivo levels of TH1 and TH2 cytokines with viremia in HAART patients with and without opportunistic infectionsJOURNAL OF MEDICAL VIROLOGY, Issue 4 2006Sardar Sindhu Abstract TH1/TH2 cytokines' imbalance is critical to HIV-1 progression and pathogenesis. Opportunistic infections-related cytokine perturbations in the setting of highly active antiretroviral therapy (HAART) are unclear. The objective of this cross-sectional study was to identify the relationship between TH1/TH2 cytokines and viremia in HAART patients with/without opportunistic infections. Sera from 17 HAART patients with and 43 without opportunistic infections, and 20 HIV-seronegative controls were used to measure the levels of IL-2, IFN-,, IL-4, and IL-10 proteins and mRNAs by ELISA and RNase protection assays, respectively. Ex vivo cytokine production by the CD4+/CD8+ T cells from four low and four high viremia patients randomly selected from non-opportunistic infection group was also evaluated. Serum IL-2 and IFN-, levels were lower (P,<,0.05) in patients than controls; this reduction was more pronounced for IFN-, in non-opportunistic infection patients. IL-4 and IL-10 were higher in patients than controls; this elevation was more remarkable in patients with opportunistic infections. Serum TH1/TH2 cytokine levels correlated with viremia. In vitro cytokine production assays showed that CD4+ T cells from low viremia patients mainly produced IL-2 and IFN-,, CD8+ T cells from high viremia patients produced IL-4, and both subsets comparably produced IL-10 in patients with similar viremia. Positive correlations between sera/supernatant proteins and cellular mRNAs were also found statistically significant (P,<,0.05). It was therefore concluded that in vivo TH1/TH2 cytokine levels in HAART patients and their ex vivo production by the CD4+/CD8+ T cells correlated with viremia and were also modulated by the presence of opportunistic infections in these patients. J. Med. Virol. 78:431,439, 2006. © 2006 Wiley-Liss, Inc. [source] Evaluation of 80 children with prolonged feverPEDIATRICS INTERNATIONAL, Issue 5 2003Ozgur Cogulu Abstract Background:,Several studies have been published regarding the etiology and evaluation of a child with prolonged fever, however, the reasons for the prolonged fever have changed during the years. The present study aims to determine the causes of prolonged fever, to investigate the relationship of fever using some basic laboratory tests, and to establish guidelines for the approach in those children. Methods:,The charts of 80 out of 17 490 hospitalized children who were seen between 1996 and 2001 with prolonged fever of longer than 2 weeks and unknown origin were reviewed in the university hospital of Izmir, Turkey. Their charts were evaluated in respect of age, sex, growth curves, educational level of their families, the duration and the magnitude of fever, causes of fever, and basic laboratory investigations such as white blood cell, blood smear, hemoglobin, erythrocyte sedimentation rate, and C-reactive protein. Results:,Forty-four (55.00%) were boys and 36 (45.00%) were girls. Forty-four children (55.00%) were aged between 1 month and 2 years, 21 (26.25%) were aged 3,6 years, seven (8.75%) were aged 7,10 years, and eight (10.00%) were older than 10 years. The mean age was 3.87 ± 4.17 years (range 3 months,17 years). Forty-six children (57.50%) had a prolonged fever that had lasted from 15,30 days, 18 (22.50%) from 31,60 days, and 16 (20.00%) had fever lasting more than 60 days. Final diagnosis had been reached in 70 of the 80 children (87.50%). The most common causes were infection (47/80), followed by immune deficiency (6/80), collagen tissue disorder (5/80), neoplasia (2/80), and miscellaneous (10/80) such as central fever in three, diabetes insipidus in two, familial Mediterranean fever in two, Kawasaki disease, foreign body in the respiratory system, and Crohn disease in one patient each. Among the laboratory tests white blood cell count, hemoglobin level and blood smear distribution of infection group were statistically significant. Conclusions:,The most common cause of fever of unknown origin remains infection. The proportion of collagen tissue disorders and neoplasia have been found to be decreased. Unusual reasons such as diabetes insipidus and foreign body in the respiratory system in the miscellaneous group have been detected. Age plays important role in the diagnosis of prolonged fever, while some basic laboratory tests might give clues in the evaluation and may suggest a diagnosis. [source] Incidence of seropositivity to bordetella pertussis and mycoplasma pneumoniae infection in patients with chronic laryngotracheitis,THE LARYNGOSCOPE, Issue 9 2009FACS, Mary Es Beaver MD Abstract Objectives/Hypothesis: Determine the incidence of bordetella pertussis and mycoplasma pneumonia infection in patients with chronic laryngotracheitis. Study Design: A prospective case study. Methods: Fifty-four consecutive adult patients presenting with symptoms (throat clearing, hoarseness, cough, globus) and signs (laryngeal and subglottic erythema and edema) of chronic laryngotracheitis (CLTR) for >6 weeks were included in the study. A single blood draw for anti-pertussis toxin IgG, IgA, IgM, and mycoplasma IgM was performed at presentation. Duration of symptoms, symptom score (Reflux Symptom Index [RSI]), and physical exam score were recorded. Results: Thirteen patients (24%) had elevated IgA and IgG to pertussis toxin. Nine patients (17%) had elevated IgM to pertussis toxin. Eight patients (15%) had elevated IgM to mycoplasma pneumoniae. There were no significant differences in symptom duration, RSI score, or Voice Handicap Index-10 score among patients with current infection, recent past infection, or no infection. Subglottic erythema scores were significantly higher for patients with current or recent past infection compared to the no infection group. Patients with current infection or recent past infection had significantly more tracheal erythema than supraglottic or vocal fold erythema. Conclusions: Bordetella pertussis and mycoplasma pneumoniae infection play a significant role in the etiology of CLTR. Pertussis can be a mild but chronic presentation and may not produce typical symptoms of severe cough. Symptom duration and severity cannot differentiate between CLTR of infectious or other etiology. Infection should be considered in patients with CLTR that have significant tracheal erythema. Laryngoscope, 2009 [source] Influence of implantation interval on the long-term biocompatibility of surgical meshBRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 8 2002Dr B. Klosterhalfen Background: The aim was to study the long-term tissue response to polypropylene mesh. Methods: This was a retrieval study that investigated 76 polypropylene meshes with a median implantation interval of 18 (range 2,180) months. Mesh was explanted following hernia recurrence, infection or pain. The median implantation interval was 20 (range 4,180) months in the recurrence group, 30 (range 5,48) months in the pain group and 10 (range 2,56) months in the infection group (P < 0·05, infection versus pain or recurrence). The inflammatory response was determined by immunohistochemistry of macrophages (CD68), polymorphonuclear granulocytes (CD15) and T and B lymphocytes (CD3 and CD20). The cell turnover within the interface mesh fibre,recipient tissue was measured by TUNEL for apoptosis or DNA strand breaks, Ki67 for cell proliferation and heat-shock protein (HSP) 70 for cell stress. Results: With the exception of HSP-70, levels of all variables decreased over time. Sex, age, type of previous operation or location of the mesh did not have a significant influence. Conclusion: Long-term incorporated polypropylene mesh in humans has a more favourable tissue response with increasing implantation interval. © 2002 British Journal of Surgery Society Ltd [source] | |||||||||||||