Swedish Institute

About: Swedish Institute is a government organization based out in Stockholm, Sweden. It is known for research contribution in the topics: Population & Health care. The organization has 1657 authors who have published 2301 publications receiving 103682 citations. The organization is also known as: Svenska Institutet.

Clearance of circulating Epstein-Barr virus DNA in children with acute malaria after antimalaria treatment.

Abstract: Children living in malaria-endemic regions have a high incidence of Burkitt lymphoma (BL), the etiology of which involves Plasmodium falciparum malaria and Epstein-Barr virus (EBV) infections. In the present study, we compared EBV DNA loads in plasma and saliva samples from Ugandan children with acute malaria (M + ) at the time of diagnosis and 14 days after antimalaria treatment, children without malaria (M), and children with BL. EBV DNA was detected, by real-time polymerase chain reaction, in 31% of the plasma and in 79% of the saliva samples from children in the M + group. Antimalaria treatment led to clearance of plasma viral load in 85% of the cases but did not affect the levels in saliva. There was a significant difference in plasma EBV loads across the groups. The lowest levels were detected in samples from the M group, increased levels were detected in samples from the M + group, and levels reached the highest values in samples from children with BL. The same trend was evident in the frequency and levels of anti-BZLF1 antibodies, which is indicative of viral reactivation. In the M + group, the positive plasma samples clustered around 7‐9 years of age, the peak incidence of BL. The clearance of circulating EBV after antimalaria treatment suggests a direct relationship between active malaria infection and viral reactivation.

Enterococcus faecalis infection in root canals – host‐derived or exogenous source?

Abstract: Aims: Enterococcus faecalis is associated with a significant number of refractory endodontic infections. Previous studies report a prevalence of Ent. faecalis ranging from 24% up to 77% in teeth with failed endodontic treatment. The origin of the micro-organism remains unclear, as enterococci do not belong to the normal oral microflora. The aim of this study was to determine whether these enterococci were of endogenous or exogenous origin. Methods and Results: Fifty consecutive patients with apical periodontitis in need of endodontic orthograde re-treatment were included. Samples were collected from root canals, saliva and faeces and subjected to microbiological culturing. The genetic relationship between Ent. faecalis from root canals and isolates from the different host sources was determined using pulsed-field gel electrophoresis. In 16% (8 ⁄50) of the patients, enterococci were collected from the root canal samples. The genetic analysis showed that the isolates from the root canals were not related to those from the normal gastrointestinal microflora. None of these patients had enterococci in their saliva samples. Conclusions: Endodontic infections with Ent. faecalis are probably not derived from the patient’s own normal microflora, which indicates that these infections ent. faecalis are of exogenous origin. Significance and Impact of the Study: This is the first study to genetically compare endodontic infectious Ent. faecalis isolates with isolates from the hosts’ own normal microflora.

Impact of anti-rheumatic treatment on immunogenicity of pandemic H1N1 influenza vaccine in patients with arthritis

Abstract: An adjuvanted pandemic H1N1 influenza (pH1N1) vaccine (Pandemrix®) was reported as highly immunogenic resulting in seroconversion in 77 to 94% of adults after administration of a single dose. The aim of the study was to investigate the impact of different anti-rheumatic treatments on antibody response to pH1N1 vaccination in patients with rheumatoid arthritis (RA) and spondylarthropathy (SpA). Patients with arthritis (n = 291; mean age 57 years, 64% women) participated. Hemagglutination inhibition (HI) assay was performed on blood samples drawn before and after a mean (SD) of 8.3 (4) months following vaccination. A positive immune response i.e. seroconversion was defined as negative prevaccination serum and postvaccination HI titer ≥40 or a ≥4-fold increase in HI titer. All patients were divided into predefined groups based on diagnosis (RA or SpA) and ongoing treatment: methotrexate (MTX), anti-tumor necrosis factor (anti-TNF) as monotherapy, MTX combined with anti-TNF, other biologics (abatacept, rituximab, tocilizumab) and non-steroidal anti-inflammatory drugs (NSAIDs)/analgesics. Predictors of positive immune response were studied using logistic regression analysis. The percentage of patients with positive immune response in the different treatment groups was: 1. RA on MTX 42%; 2. RA on anti-TNF monotherapy 53%; 3. RA on anti-TNF + MTX 43%; 4. RA on other biologics (abatacept 20%, rituximab 10% and tocilizumab 50%); 5. SpA on anti-TNF monotherapy 76%; 6. SpA on anti-TNF + MTX 47%; and 7. SpA on NSAIDs/analgesics 59%. RA patients on rituximab had significantly lower (P < 0.001) and SpA on anti-TNF monotherapy significantly better response rates compared to other treatment groups (P 0.001 to 0.033). Higher age (P < 0.001) predicted impaired immune response. Antibody titers 3 to 6 months after vaccination was generally lower compared to those within the first 3 months but no further decrease in titers were observed 6 to 22 months after vaccination. Rituximab treatment severely reduced antibody response to pH1N1 influenza vaccine. The other treatment groups showed acceptable antibody responses. Protective antibody titers could be detected up to 22 months after vaccination in the current patient population, with the exception of rituximab treated patients.