Effect of the Novel Influenza A (H1N1) Virus in the Human Immune System

BACKGROUND: The pandemic by the novel H1N1 virus has created the need to study any probable effects of that infection in the immune system of the host. METHODOLOGY/PRINCIPAL FINDINGS: Blood was sampled within the first two days of the presentation of signs of infection from 10 healthy volunteers; from 18 cases of flu-like syndrome; and from 31 cases of infection by H1N1 confirmed by reverse RT-PCR. Absolute counts of subtypes of monocytes and of lymphocytes were determined after staining with monoclonal antibodies and analysis by flow cytometry. Peripheral blood mononuclear cells (PBMCs) were isolated from patients and stimulated with various bacterial stimuli. Concentrations of tumour necrosis factor-alpha, interleukin (IL)-1beta, IL-6, IL-18, interferon (FN)-alpha and of IFN-gamma were estimated in supernatants by an enzyme immunoassay. Infection by H1N1 was accompanied by an increase of monocytes. PBMCs of patients evoked strong cytokine production after stimulation with most of bacterial stimuli. Defective cytokine responses were shown in response to stimulation with phytohemagglutin and with heat-killed Streptococcus pneumoniae. Adaptive immune responses of H1N1-infected patients were characterized by decreases of CD4-lymphocytes and of B-lymphocytes and by increase of T-regulatory lymphocytes (Tregs). CONCLUSIONS/SIGNIFICANCE: Infection by the H1N1 virus is accompanied by a characteristic impairment of the innate immune responses characterized by defective cytokine responses to S.pneumoniae. Alterations of the adaptive immune responses are predominated by increase of Tregs. These findings signify a predisposition for pneumococcal infections after infection by H1N1 influenza

Moxifloxacin prophylaxis against experimental aortic valve endocarditis due to streptococcus oralis

Objectives: Studies related to the prophylactic efficacy of newer fluoroquinolones against infective endocarditis are scarce. The aim of this study was to evaluate the efficacy of moxifloxacin, a quinolone active in vitro against Gram-positive cocci, in preventing streptococcal aortic valve endocarditis. Methods: Non-bacterial thrombotic endocarditis of the aortic valve was induced in rabbits by the insertion of a polyethylene catheter. Twenty-four hours later, rabbits were randomly assigned to a control group, and groups receiving either a single dose of moxifloxacin (15 mg/kg, intravenously), or two doses of ampicillin (40 mg/kg, intravenously), 2 h apart. Ampicillin and moxifloxacin were administered 0,5 and 1 h, respectively, prior to the intravenous inoculation of 107 CFU of Streptococcus oralis. The rabbits were sacrificed 3 days after bacterial challenge and vegetations were cultured quantitatively. Results: Seventeen out of 18 (94%) of the control animals developed infected vegetations. In rabbits challenged with this very high inoculum, moxifloxacin and ampicillin prevented endocarditis in 81% (p < 0.001 versus controls) and in 50% (p = 0,022 versus controls) of animals, respectively. The difference between ampicillin and moxifloxacin was not statistically significant (p = 0.128) (Fisher exact test). The mean ± SD bacterial densities in vegetations from rabbits infected (in log10CFU/g) were: Controls 9,28 ± 0,95a (n=17), ampicillin 7,78 ± 2,07b (n=7) and, moxifloxacin 8,38 ± 0,77c (n=3). Statitics: a vs b: p=0,065 (ns), a vs c: p=0,491 (ns) (Kruskal-Wallis test). Moxifloxacin levels at 1, 2, 4, 8 and 24 h post-dosing were (mean ± SD): 3,45±0,8 mg/L (n=13), 2,42±0,66 mg/L (n=14), 1,2±0,46 mg/L (n=13), 0,28±0,11 mg/L (n=13) and undetectable (n=6), respectively. Ampicillin levels at 0,5, 1, 2 h after the first dose and 2 h after the second dose were (mean ± SD): 9,56±3,72 mg/L, 3,24±1,19 mg/L, 0,58±0,48 mg/L, 0,73±0,47 mg/L, respectively (n=15). Conclusions: Moxifloxacin was at least as effective as ampicillin in preventing streptococcal endocarditis

Reliability, validity and psychometric properties of the Greek translation of the posttraumatic stress disorder scale

The Greek version of the Davidson Trauma Scale (DTS) was developed to respond to the need of Greek-speaking individuals. The translated questionnaire was administered to 128 HIV outpatients (aged 37.1±9.1) and 166 control patients (aged 32.4±13.4). In addition to the DTS Greek scale, subjects were assessed with two other scales useful for assessing validity. For each factor analyses two components were extracted, based on Cattell’s scree test. The two components solution accounted for 55.34% of the total variation in case of frequency variables and 61.45% in case of severity variables. The Cronbach’s alpha coefficient and Guttman split-half coefficient of the DTS scale were 0.93 and 0.88 respectively. The test-retest reliability of the Greek version of DTS scale proved to be satisfactory. Individual items had good intra-class correlation coefficients higher than 0.5, which means that all questions have high levels of external validity. The psychometric strength of interview for posttraumatic stress disorder-Greek version it’s reliable for its future use, particularly for screening subjects with possible diagnosis of posttraumatic stress disorder

Colonisation with vancomycin- and linezolid-resistant Enterococcus faecium in a university hospital: molecular epidemiology and risk factor analysis

During a hospital-wide prospective point prevalence survey of faecal carriage and environmental colonisation of vancomycin-resistant enterococci in a tertiary care university hospital in Athens (Greece), five clinical and one environmental isolate from a light switch (all in the haematology ward) were identified as vancomycin- and linezolid-resistant vanA-positive Enterococcus faecium (VLRE). The studied isolates exhibited a linezolid minimum inhibitory concentration of 12 mu g/mL and carried at least one mutated copy of the 23S rRNA gene, as shown by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis to detect the G2576T mutation. The enterococcal surface protein (esp) gene was detected by PCR in all isolates. Molecular typing with pulsed field gel electrophoresis (PFGE) showed that the environmental and four of the five clinical isolates were genetically related. None of the colonised patients were previously exposed to linezolid, although heavy linezolid use was noted in the institution. A case-control study was performed to assess risk factors for VLRE colonisation. In univariate analysis, immunodeficiency, underlying haematological malignancy, duration of any antimicrobial treatment before VLRE isolation, and hospitalisation in the haematology ward were pointed out as possible risk factors. A multidisciplinary approach including intensified hand hygiene, patient contact isolation, disinfection of the inanimate environment and antibiotic restriction resulted in early containment of the VLRE colonisation outbreak. (C) 2008 Elsevier B. V. and the International Society of Chemotherapy. All rights reserved

Assessment of Seroconversion after SARS-CoV-2 Vaccination in Patients with Lung Cancer

Background: SARS-CoV-2 mortality rates are significantly higher in patients with lung cancer compared with the general population. However, little is known on their immunization status after vaccination. Methods: To evaluate the humoral response (seroconversion) of patients with lung cancer following vaccination against SARS-COV-2 (Group A), we obtained antibodies against SARS-CoV-2 spike (S) protein both at baseline and at different time points after the first dose of SARS-CoV-2 vaccine (two to three weeks [T1], six weeks &plusmn; one week [T2], 12 weeks &plusmn; three weeks [T3], and 24 weeks &plusmn; three weeks [T4]). Antibodies were also acquired from a control cohort of non-lung cancer patients (Group B) as well as a third cohort containing healthy controls (Group C) at all time points and at T4, respectively, to make comparisons with Group A. Analysis of antibody response at different time points, association with clinicopathologic parameters, and comparisons with control groups were performed. Results: A total of 125 patients with lung cancer were included in the analysis (96 males [74.3%], median age of 68 years [46&ndash;91]. All study participants received two vaccine doses (BNT162b2, mRNA-1273, AZD1222). Analysis of anti-SARS-CoV-2 S antibody titers showed minimal response at T1 (0.4 [0.4&ndash;48.6] IU/mL). Antibody response peaked at T2 (527.0 [0.4&ndash;2500] IU/mL) and declined over T3 (323.0 [0.4&ndash;2500] IU/mL) and T4 (141.0 [0.4&ndash;2500] IU/mL). Active smokers had lower antibody titers at T2 (p = 0.04), T3 (p = 0.04), and T4 (p &lt; 0.0001) compared with former or never smokers. Peak antibody titers were not associated with any other clinicopathologic characteristic. No significant differences were observed compared with Group B. However, lung cancer patients exhibited significantly decreased antibody titers compared with Group C at T4 (p &lt; 0.0001). Conclusions: Lung cancer patients demonstrate sufficient antibody response six weeks after the first dose of vaccine against SARS-CoV-2 when vaccinated with two-dose regimens. Rapidly declining antibody titers six weeks after the first dose underline the need for a third dose three months later, in patients with lung cancer, and especially active smokers

Assessment of Seroconversion after SARS-CoV-2 Vaccination in Patients with Lung Cancer

Background: SARS-CoV-2 mortality rates are significantly higher in patients with lung cancer compared with the general population. However, little is known on their immunization status after vaccination. Methods: To evaluate the humoral response (seroconversion) of patients with lung cancer following vaccination against SARS-COV-2 (Group A), we obtained antibodies against SARS-CoV-2 spike (S) protein both at baseline and at different time points after the first dose of SARS-CoV-2 vaccine (two to three weeks [T1], six weeks ± one week [T2], 12 weeks ± three weeks [T3], and 24 weeks ± three weeks [T4]). Antibodies were also acquired from a control cohort of non-lung cancer patients (Group B) as well as a third cohort containing healthy controls (Group C) at all time points and at T4, respectively, to make comparisons with Group A. Analysis of antibody response at different time points, association with clinicopathologic parameters, and comparisons with control groups were performed. Results: A total of 125 patients with lung cancer were included in the analysis (96 males [74.3%], median age of 68 years [46–91]. All study participants received two vaccine doses (BNT162b2, mRNA-1273, AZD1222). Analysis of anti-SARS-CoV-2 S antibody titers showed minimal response at T1 (0.4 [0.4–48.6] IU/mL). Antibody response peaked at T2 (527.0 [0.4–2500] IU/mL) and declined over T3 (323.0 [0.4–2500] IU/mL) and T4 (141.0 [0.4–2500] IU/mL). Active smokers had lower antibody titers at T2 (p = 0.04), T3 (p = 0.04), and T4 (p p Conclusions: Lung cancer patients demonstrate sufficient antibody response six weeks after the first dose of vaccine against SARS-CoV-2 when vaccinated with two-dose regimens. Rapidly declining antibody titers six weeks after the first dose underline the need for a third dose three months later, in patients with lung cancer, and especially active smokers