Systematic review and meta-analysis of hepatitis C virus infection and HIV viral load: New insights into epidemiologic synergy

INTRODUCTION: Hepatitis C virus (HCV) and HIV infection frequently co-occur due to shared transmission routes. Co-infection is associated with higher HCV viral load (VL), but less is known about the effect of HCV infection on HIV VL and risk of onward transmission. METHODS: We undertook a systematic review comparing 1) HIV VL among ART-naïve, HCV co-infected individuals versus HIV mono-infected individuals and 2) HIV VL among treated versus untreated HCV co-infected individuals. We performed a random-effects meta-analysis and quantified heterogeneity using the I2 statistic. We followed Cochrane Collaboration guidelines in conducting our review and PRISMA guidelines in reporting results. RESULTS AND DISCUSSION: We screened 3925 articles and identified 17 relevant publications. A meta-analysis found no evidence of increased HIV VL associated with HCV co-infection or between HIV VL and HCV treatment with pegylated interferon-alpha-2a/b and ribavirin. CONCLUSIONS: This finding is in contrast to the substantial increases in HIV VL observed with several other systemic infections. It presents opportunities to elucidate the biological pathways that underpin epidemiological synergy in HIV co-infections and may enable prediction of which co-infections are most important to epidemic control

Actinobaculum schaalii - invasive pathogen or innocent bystander? A retrospective observational study

Actinobaculum schaalii is a Gram-positive, facultative anaerobic coccoid rod, classified as a new genus in 1997. It grows slowly and therefore is easily overgrown by other pathogens, which are often found concomitantly. Since 1999, Actinobaculum schaalii is routinely investigated at our hospital, whenever its presence is suspected due to the detection of minute grey colonies on blood agar plates and negative reactions for catalase. The objective of this study was to determine the clinical significance of Actinobaculum schaalii, identified in our microbiology laboratory over the last 11 years.; All consecutive isolates with Actinobaculum schaalii were obtained from the computerized database of the clinical microbiology laboratory and patients whose cultures from any body site yielded this pathogen were analyzed. Observation of tiny colonies of Gram-positive, catalase-negative coccoid rods triggered molecular identification based on 16S rRNA gene sequencing.; 40 isolates were obtained from 27 patients during the last 11 years. The patient's median age was 81 (19-101) years, 25 (92.6%) had underlying diseases and 12 (44.4%) had a genitourinary tract pathology. Actinobaculum schaalii was isolated in 12 urine cultures, 21 blood cultures, and 7 deep tissue biopsies. Twenty-five (62.5%) specimens were monobacterial, the remaining 15 (37.5%) were polybacterial 7/7 deep tissue samples (three bloodcultures and five urine cultures). Recovery from urine was interpreted as colonization in 5 (18.6%) cases (41.6% of all urine samples). Six (22.2%) suffered from urinary tract infections, six (22.2%) from abscesses (skin, intraabdominal, genitourinary tract, and surgical site infections) and 10 (37.0%) from bacteremia.; In this largest case series so far, detection of Actinobaculum schaalii was associated with an infection--primarily sepsis and abscesses--in 81.5% of our patients. Since this pathogen is frequently part of polymicrobial cultures (42.5%) it is often overlooked considered a contaminant. Detection of Actinobaculum schaalii in clinical isolates mainly reflects infection indicating that this Gram-positive rod is not an innocent bystander

Fracture Mechanics at Intermediate Rates of Loading : The Influence of the Acceleration on Compact Tension Tests

Compact Tension specimens were loaded at 1 and 7 m/s with two different accelerations imposed. Experimental photoelastic patterns recorded by a high speed camera were compared with those simulated by dynamic elastic Finite Element (FE) analysis. The positive results of this comparison validated the FE analysis. It is demonstrated that when the initial acceleration of the specimen is low (using a damper in the loading device), static analysis can be applied for both testing speeds used. In high accelerations tests (without damper used), a transient dynamic stress state in the specimens is found, therefore a dynamic analysis should be used. Furthermore, in high acceleration tests a transient mixed mode of loading at the crack tip occurs.Deux accélérations différentes sont imposées à des éprouvettes de tension compacte (CT) sollicitées à 1 et 7 m/s. Les contraintes sont visualisée par la photoélasticité à l'aide d'une caméra à haute vitesse, et comparées avec les franges photoélastiques simulées par éléments finis. Les résultats positifs de ces comparaisons permettent ce valider les calculs. Il est démontré par là que lorsque l'accélération initiale de l'échantillon est réduite par un amortisseur dans le système de chargement, l'analyse statique est applicable. Pour les accélérations élevées, un état de contrainte dynamique transitoire est prédominent dans la phase initiale du chargement, et l'analyse dynamique doit être appliquée. De plus, dans ces tests une mixité de mode est présente en tête de fissure

Live and Heterogeneous Migration of Execution Environments

International audienceApplication migration and heterogeneity are inherent issues of pervasive systems. Each implementation of a pervasive system must provide its own migration framework which hides heterogeneity of the different resources. This leads to the development of many frameworks that perform the same functionality. We propose a minimal execution environment, the micro virtual machine, that factorizes process migration implementation and offers heterogeneity, transparency and performance. Systems implemented on top of this micro virtual machine, such as our own Java virtual machine, will therefore automatically inherit process migration capabilities

Toughening mechanisms of rubber toughened PMMA.

Toughening mechanisms of three types of rubber toughened poly (methyl methacrylate) (RT-PMMA) were investigated under mode 1 loading condition by optical and electron microscopies in conjunction with the quantitative evaluation of mode I fracture toughness. Polarizing optical microscopy clearly exhibited damage zone development ahead of a crack-tip in the RT PMMA's. The three RT PMMA's revealed different shapes of the damage zone. Transmission electron microscopy exhibited microcrazes generated in the equator of rubber particles within the damage zones. Extensive deformation of rubber particles corresponding to localized shear yielding of the PMMA matrix was also found in a region close to a propagating cracktip. In addition, cavitation of rubber particles was observed in the vicinity of the crack. It is therefore understood that the toughening of the RT PMMA's is due to energy dissipation caused by the microdamage formations such as microcrazing, matrix shear deformation and rubber particle captation ahead of the crack-tip