Risk factors for total joint arthroplasty infection in patients receiving tumor necrosis factor α-blockers: a case-control study

Introduction

The objective of this study was to assess natural microbial agents, history and risk factors for total joint arthroplasty (TJA) infections in patients receiving tumor necrosis factor (TNF)α-blockers, through the French RATIO registry and a case-control study.

Methods

Cases were TJA infections during TNFα-blocker treatments. Each case was compared to two controls (with TJA and TNFα-blocker therapy, but without TJA infection) matched on age (±15 years), TJA localization, type of rheumatic disorder and disease duration (±15 years). Statistical analyses included univariate and multivariate analyses with conditional logistic regression.

Results

In the 20 cases (18 rheumatoid arthritis), TJA infection concerned principally the knee (n = 12, 60%) and the hip (n = 5, 25%). Staphylococcus was the more frequent microorganism involved (n = 15, 75%). Four patients (20%) were hospitalized in an intensive care unit and two died from infection. Eight cases (40%) versus 5 controls (13%) had undergone primary TJA or TJA revision for the joint subsequently infected during the last year (P = 0.03). Of these procedures, 5 cases versus 1 control were performed without withdrawing TNFα-blockers (P = 0.08). In multivariate analysis, predictors of infection were primary TJA or TJA revision for the joint subsequently infected within the last year (odds ratio, OR = 88.3; 95%CI 1.1-7,071.6; P = 0.04) and increased daily steroid intake (OR = 5.0 per 5 mg/d increase; 1.1-21.6; P = 0.03). Case-control comparisons showed similar distribution between TNFα-blockers (P = 0.70).

Conclusions

In patients receiving TNFα-blockers, TJA infection is rare but potentially severe. Important risk factors are primary TJA or TJA revision within the last year, particularly when TNFα-blockers are not interrupted before surgery, and the daily steroid intake.     

Consequences of concurrent Ascaridia galli and Escherichia coli infections in chickens

   

Three experiments were carried out to examine the consequences of concurrent infections with Ascaridia galli and Escherichia coli in chickens raised for table egg production. Characteristic pathological lesions including airsacculitis, peritonitis and/or polyserositis were seen in all groups infected with E. coli. Furthermore, a trend for increased mortality rates was observed in groups infected with both organisms which, however, could not be confirmed statistically. The mean worm burden was significantly lower in combined infection groups compared to groups infected only with A. galli. It was also shown that combined infections of E. coli and A. galli had an added significant negative impact on weight gain.     

The evolutionary radiation of Arvicolinae rodents (voles and lemmings): relative contribution of nuclear and mitochondrial DNA phylogenies

Background  

Mitochondrial and nuclear genes have generally been employed for different purposes in molecular systematics, the former to resolve relationships within recently evolved groups and the latter to investigate phylogenies at a deeper level. In the case of rapid and recent evolutionary radiations, mitochondrial genes like cytochrome b (CYB) are often inefficient for resolving phylogenetic relationships. One of the best examples is illustrated by Arvicolinae rodents (Rodentia; Muridae), the most impressive mammalian radiation of the Northern Hemisphere which produced voles, lemmings and muskrats. Here, we compare the relative contribution of a nuclear marker – the exon 10 of the growth hormone receptor (GHR) gene – to the one of the mitochondrial CYB for inferring phylogenetic relationships among the major lineages of arvicoline rodents.     

Interest of colchicine for the treatment of cystic fibrosis patients. Preliminary report

Cystic fibrosis (CF) lung disease is characterized by persistent inflammation. Antiinflammatory drugs, such as corticosteroids and ibuprofen, have proved to slow the decline of pulmonary function although their use is limited because of frequent adverse events. We hypothesized that colchicine could be an alternative treatment because of its antiinflammatory properties and upregulatory effect on cystic fibrosis transmembrane regulator (CFTR) closely related proteins. We herein present results obtained in an open study of eight CF children treated with colchicine for at least 6 months. Clinical status was better in all patients and respiratory function tests significantly improved in five. Median duration of antibiotherapy decreased significantly. These preliminary results support our hypothesis of a beneficial effect of colchicine in CF patients and stress the need for a controlled therapeutic trial.     

Resistance to serum killing may contribute to differences in the abilities of capsulate and non-capsulated isolates of lactococcus garvieae to cause disease in rainbow trout (Oncorhynchus mykiss L.)

Three capsulated and two non-capsulated isolates of Lactococcus garvieae were investigated in terms of their wall proteins, virulence and interactions with rainbow trout immunoglobulin (Ig). All isolates were similar in integral membrane protein profile, and all were able to bind non-immune rainbow trout Ig, although different proteins appeared to be involved in Ig binding. However, whilst capsulated isolates were highly virulent, non-capsulated isolates were avirulent. This appeared to correlate with susceptibility of the non-capsulated isolates to rainbow trout normal serum. In contrast, the capsulated isolates were resistant to both normal and immune serum killing. In spite of this, passive immunisation of rainbow trout with specific anti-serum to L. garvieae was able to protect against challenge by capsulated isolates of L. garvieae. This suggests the antibody may have some other role in protection against disease caused by this important Gram-positive bacterial fish pathogen.     

Electrotransformation of Lactobacillus manihotivorans LMG 18010T and LMG 18011

An electroporation procedure was developed for the genetic transformation of intact cells of Lactobacillus manihotivorans , a new Lactobacillus species isolated from cassava sour starch fermentation in Colombia. Transformation efficiency of Lact. manihotivorans strains LMG 18010^T and LMG 18011 was measured and compared with electroporability of Lact. plantarum strains NCIMB 8299 and LMG 9211, by investigating the effect of changes in various parameters. For Lact. manihotivorans strain LMG 18010^T, the composition of the culture medium, such as the type of peptone and the presence of Tween-80, was found to be the most critical parameter, as well as the aeration conditions of the culture; better electroporation was obtained without air. The presence of MgCl₂ in the recovery medium was favourable to regeneration of electroporated cells. Plasmid-curing of the cells did not improve their electroporability. Transformants were obtained with Lact. manihotivorans strain LMG 18010^T and the plasmids pLZ12 and pGK13, whereas Lact. manihotivorans strain LMG 18011 was transformable with plasmids pLP825 and pLZ12, with different electroporation conditions.     

The relative influence of density and kinship on dispersal in the common lizard

We experimentally investigated the relative role of kinshipand density on juvenile dispersal in the common lizard. A fewdays after birth, juveniles were introduced into seminaturalendosures, where they experienced different social environmentsin the first experiment we varied the density of unrelated adults(males or females) within the enclosure (0, 1, or 2 adults),and in the second experiment, we varied the level of kinshipand familiarity between juveniles and adults. Each enclosurewas connected to a second enclosure by small holes which allowedonly juveniles to move between enclosures. Juvenile movementswere monitored during 14 days after birth, as juvenile dispersalis mainly completed within 10 days after birth under naturalconditions. Most juveniles did not return to the first enclosure.Sex had no effect on juvenile dispersal. Adult densityand kinshipwith adults both affected dispersal. Adult female density increasedjuvenile dispersal whatever the level of kinship and familiaritywith the females. Dispersers had better body condition thannondispersers at high female densit and this difference wassignificantly greater when the mother and the familiar femalewere present in the enclosure. Furthermore, body condition ofmothers and familiar females was positively correlated withjuvenile dispersal, whereas there was no such correlation inthe case of unfamiliar and unrelated females. These resultsstrongly suggest that adult female density is a major factorpromoting dispersal in this species and that both intraspecificand kin competition motivate dispersal.     

Isolation and characterization of new amylolytic strains of Lactobacillus fermentum from fermented maize doughs (mawè and ogi) from Benin

Twelve amylolytic heterofermentative lactic acid bacteria were isolated in Benin from the fermentation processes of maize sour dough, namely ogi and mawè. Discrimination of strains was performed by DNA restriction patterns and compared with carbohydrate fermentation profiles. This allowed two new amylolytic strains, Ogi E1 and Mw2, belonging to the species Lactobacillus fermentum , to be distinguished. Strains Ogi E1 and Mw2 presented different amylolytic activities; amylase from strain Mw2 was more acidophilic and mesophilic than amylase produced by strain Ogi E1.