Aminopeptidase activity in strains of oral streptococci

Ten strains of oral streptococci were analyzed for aminopeptidase activity by isoelectric focusing and crossed immunoelectrophoresis together with enzyme staining procedures. Substrate specificities were determined using 15 aminoacyl-β-naphthylamides. All 10 strains tested showed enzyme activity with the arginine and leucine substrates. None of the strains exhibited activity with the glycine, cystine, or proline substrates. Some strains had multiple enzyme bands with some of the substrates. All strains had aminopeptidase bands located in the pi range 4.1–4.3, except Streptococcus mutans IB and Streptococcus milleri NCTC 10708. The isoelectric profiles of these strains, having enzyme bands in the range 4.45–4.9, differed markedly from the others. These were also the only strains where no arginine aminopeptidase cross-reactivity occurred with the Streptococcus mitis ATCC 903 antiserum.     

The effects of task complexity on brake response time before and after primary right total knee arthroplasty

Marques CJ, Cabri J, Barreiros J, Carita AI, Friesecke C, Loehr JF. The effects of task complexity on brake response time before and after primary right total knee arthroplasty.

Objective

To study the effects of an increase in task complexity on brake response time (BRT) in patients undergoing total knee arthroplasty (TKA).

Design

A prospective repeated-measures design was used. The measurements took place 1 day before and 10 and 30 days after surgery.

Setting

Clinic.

Participants

The data of patients (N=21) who were admitted for primary total arthroplasty of the right knee were pooled for analysis.

Interventions

On each measurement day patients performed 5 practice and 10 test trials for 2 tasks (1 simple, 1 complex) in a car simulator. Task complexity was increased by adding a second movement to the first task performed.

Main Outcome Measures

BRT, reaction time (RT), and movement time were assessed.

Results

An increase in task complexity increased BRT, RT, and movement time at all measurement times. Right TKA increased BRT by increasing movement time. Thirty days after surgery BRT was no longer increased compared with preoperative values in both tasks.

Conclusions

Task complexity consistently increased BRT and its components. The effects of task complexity remained constant throughout the 3 measurements. After right TKA, we suggest patients should be advised to wait 30 days after surgery before resuming driving.     

What is considered important for life balance? Similarities and differences among some working adults

Life balance seems subjective, health related, and multidimensional. However, the concept is complex. Exploring what people themselves consider more or less important for their life balance and whether this differs between people would develop new knowledge. Q methodology was chosen for the present study, in which 32 working men and women without recent long-term sick leave participated. They sorted 42 statements regarding life balance according to their importance for each participant's life balance. The analysis resulted in four different viewpoints concerning life balance. All four viewpoints considered good relationships with those closest to them, as well as knowing that these people were doing well, as important. Each viewpoint also showed a unique orientation towards what was considered important for life balance: occupational balance (viewpoint 1), self-actualization (viewpoint 2), self-awareness (viewpoint 3), and reciprocal relationships (viewpoint 4). The results. showed support for life balance as being a subjective, multidimensional, and health-related phenomenon. The results demonstrated the importance of relationships for life balance and heterogeneity in what people considered important for their own life balance.     

Relationship between leptin and C-reactive protein in young Finnish adults

CONTEXT: Leptin and C-reactive protein (CRP) concentrations are increased in inflammation, and both have been linked to increased risk for cardiovascular diseases. OBJECTIVE: The objective of the study was to explore in a population-based sample whether the relation between leptin and CRP is independent of obesity level and whether genetic causes of CRP elevation contribute to leptin levels. DESIGN: This was a population-based study including 1862 young adults (971 women; 891 men) aged 24-39 yr. SETTING: The study was conducted at five centers in Finland. MAIN OUTCOME MEASURES: Associations between leptin and CRP adjusted for obesity indices, risk factors, genetic variables, and lifestyle variables were measured. RESULTS: Women had 3.0-fold higher median concentrations of leptin (12.5 vs. 4.1 ng/ml) and 1.3-fold higher median concentrations of CRP (0.75 vs. 0.56 mg/liter) than men (P < 0.0001 in both comparisons). In univariate analyses, CRP and leptin were significantly intercorrelated (r = 0.47, P < 0.0001 for women; r = 0.46, P < 0.0001 for men). In multiple regression analysis including age, body mass index, waist circumference, insulin, lipids, systolic and diastolic blood pressures, smoking status, and use of oral contraceptives in women, leptin was the main determinant of CRP in men (P < 0.0001) and the second most important determinant in women (P < 0.0001). A Mendelian randomization test based on genetic variants in the CRP gene (five single nucleotide polymorphisms) provided no support for CRP as a causal agent for leptin. CONCLUSIONS: Leptin, obesity, and oral contraceptive use in women were the main factors related to CRP. The relation between leptin and CRP was independent of obesity and cardiovascular risk factors.     

All known human rhinovirus species are present in sputum specimens of military recruits during respiratory infection

Human rhinoviruses (HRV) are known to cause common cold as well as more complicated respiratory infections. HRV species -A, -B and -C have all been associated with lower respiratory infections and exacerbations of asthma. However, the type distribution of strains connected to different kinds of lower respiratory conditions is not clearly known. We have analysed the presence of HRV in sputum specimens derived from military recruits with and without pre-diagnosed asthma at times of acute respiratory infection (CIAS Study, 2004-2005). The analysis was performed with HRV and HEV real-time RT-PCR assays. Subsequently we studied type distribution of HRV strains by genetic typing in the VP4/VP2 genomic region. In total 146 (38.8%) specimens were HRV-positive and 36 (9.3%) HEV-positive. No difference was found in HRV detection between the asthmatic vs. non-asthmatic patients. Most of the genetically typed strains, 18 (62.1%), belonged to HRV-A, while HRV-B strains constituted five (17.2%) of the HRV-positive strains. HRV-C strain was typed four times from the HRV-positive cases and a HEV-D strain twice. We further typed six HEV positive strains in the partial VP1 region. Three of these belonged to HRV-A and three to HEV-D. HRV-A strains were discovered throughout the study period, while HRV-C strains originated from winter and spring specimens. Interestingly, four out of five typed HRV-B strains originated from the summer season specimens.     

Preparation of Multi-Walled Carbon Nanotube/Amino-Terminated Ionic Liquid Arrays and Their Electrocatalysis towards Oxygen Reduction

Arrays of aligned multi-walled carbon nanotube-ionic liquid (MIL) were assembled on silicon wafers (Si-MIL). Formation of Si-MIL was confirmed by FTIR, AFM and Raman techniques. The electrochemical measurements indicated that Si-MIL showed good electrocatalysis towards oxygen reduction compared with MIL drop-cast on a glassy carbon electrode.     

The second gamma-H2AX assay inter-comparison exercise carried out in the framework of the European biodosimetry network (RENEB)

Abstract

Purpose: Within the EU RENEB project, seven laboratories have taken part in training and harmonisation activities to strengthen triage gamma-H2AX-based radiation exposure assessment. This has culminated in a second triage biodosimetry exercise.

Materials and methods: Whole blood and separated lymphocyte samples were homogenously irradiated with ⁶⁰Co gamma rays at 0.5, 2.5 (blind samples), 0 and 2?Gy (reference samples). Following post-exposure incubations of 4 and 24?h, 16 samples were shipped on ice packs to each partner. The samples were stained and scored for gamma-H2AX foci, using manual and/or automated fluorescence microscope scoring strategies. Dose estimates were obtained and used to assign triage categories to the samples.

Results: Average dose estimates across all the laboratories correlated well with true doses. The most accurate assignment of triage category was achieved by manual scoring of the 4-h blood and lymphocyte samples. Only three samples out of a total of 46 were miscategorized in a way that could have adversely effected the clinical management of a radiation casualty.

Conclusions: This inter-comparison exercise has demonstrated that following a recent acute radiation exposure, the gamma-H2AX assay could be a useful triage tool that can be successfully applied across a network of laboratories.