Staphylococcal chromosomal cassette mec type I, spa type, and expression of Pls are determinants of reduced cellular invasiveness of methicillin-resistant Staphylococcus aureus isolates

We have shown previously that pls, which codes for the surface protein Pls of methicillin-resistant Staphylococcus aureus (MRSA), reduces adhesion to immobilized fibronectin, fibrinogen, laminin, and immunoglobulin G as well as invasion of host cells. Here, we tested a collection of 66 clinical MRSA isolates--48 negative for pls/Pls (pls(-)/Pls(-)), 15 positive for pls/Pls (pls(+)/Pls(+)), and 3 harboring the pls gene but not expressing Pls (pls(+)/Pls(-))--for cellular invasiveness. Invasion of 293 cells by pls(+)/Pls(+) strains was lower than that by the pls(-)/Pls(-) strains (median [range], 36% [22%-70%] vs. 93% [25%-162%]). The 3 pls(+)/Pls(-) strains (median [range], 95% [63%-103%]) were as invasive as the pls(-)/Pls(-) strains. In addition, we identified a pls(+)/Pls(+) staphylococcal chromosomal cassette mec (SCCmec) IV strain. In conclusion, 3 properties--pls/Pls, SCCmec type, and spa type--strongly predicted the cellular invasiveness of MRSA strains, as indicated by good clustering. In contrast, the spa type-deduced multilocus sequence typing clonal complex (MLST-CC) was not able to predict the invasiveness of MRSA strains equally well. The underlying mechanism remains to be elucidated.     

A simple procedure for estimation of the spatial QRS/T angle from the standard 12-lead electrocardiogram

The spatial QRS/T angle has been identified as a strong predictor of adverse cardiac events. Mean QRS and T amplitudes from X, Y, and Z leads generated by a matrix transformation method are often used to calculate the QRS/T angle (QRS/T_matrix). Many investigators find this procedure cumbersome. We used electrocardiographic data files of 14 881 men and women aged 45 to 65 years from the Atherosclerosis in Communities study to derive a simple formula for estimated spatial QRS/T angle (QRS/T_simple). QRS/T_simple is calculated as the inverse cosine between the mean QRS and T vectors, which are approximated by 3 QRS_net and T_net amplitudes for each vector. QRS/T_simple explained 79% of the variance of QRS/T_matrix (r = 0.89)_. Using sex-specific thresholds, QRS/T_simple detected abnormally wide QRS/T_matrix values with a sensitivity of 91% and specificity of 88%. It is concluded that this simple method may provide a satisfactory substitute for QRS/T from the matrix transformation method.     

Effect of Retirement on Sleep Disturbances: the GAZEL Prospective Cohort Study

Objectives:

Changes in health following retirement are poorly understood. We used serial measurements to assess the effect of retirement on sleep disturbances.

Design:

Prospective cohort study.

Setting:

The French national gas and electricity company.

Participants:

Fourteen thousand seven hundred fourteen retired employees (79% men).

Measurements and Results:

Annual survey measurements of sleep disturbances ranging from 7 years before to 7 years after retirement (a mean of 12 measurements). Before retirement 22.2% to 24.6% of participants reported having disturbed sleep. According to repeated-measures logistic-regression analysis with generalized estimating equations estimation, the odds ratio (OR) for having a sleep disturbance in the postretirement period was 0.74 (95% confidence interval 0.71-0.77), compared with having a sleep disturbance in the preretirement period. The postretirement improvement in sleep was more pronounced in men (OR 0.66 [0.63-0.69]) than in women (OR 0.89 [0.84-0.95]) and in higher-grade workers than lower-grade workers. Postretirement sleep improvement was explained by the combination of preretirement risk factors suggesting removal of work-related exposures as a mechanism. The only exception to the general improvement in sleep after retirement was related to retirement on health grounds. In this group of participants, there was an increase in sleep disturbances following retirement.

Conclusions:

Repeated measurements provide strong evidence for a substantial and sustained decrease in sleep disturbances following retirement. The possibility that the health and well-being of individuals are significantly worse when in employment than following retirement presents a great challenge to improve the quality of work life in Western societies in which the cost of the aging population can only be met through an increase in average retirement age.

Citation:

Vahtera J; Westerlund H; Hall M; Sjösten N; Kivimäki M; Salo P; Ferrie JE; Jokela M; Pentti J; Singh-Manoux A; Goldberg M; Zins M. Effect of retirement on sleep disturbances: the GAZEL prospective cohort study. SLEEP 2009;32(11):1459-1466.     

Use of calcium supplements and the risk of coronary heart disease in 52–62-year-old women: The Kuopio Osteoporosis Risk Factor and Prevention Study

Background

To analyse prospectively the effect of calcium or calcium + D supplementation on coronary heart disease (CHD) in 52–62-year-old women.

Methods and results

10,555 52–62-year-old women from the population-based Kuopio Osteoporosis Risk Factor and Prevention Study (OSTPRE) who did not have CHD at baseline were followed for nearly 7 years in 1994–2001. Information about use of calcium supplements and health events was obtained from two repeated questionnaires in 1989 and 1994. Information about causes of death during the follow-up was obtained from the Statistics Finland. Information about CHD and other disease morbidity before and during the follow-up was obtained from the Registry of Specially Refunded Drugs of the Finnish Social Insurance Institution (SII). Cox's proportional-hazards models were used to estimate the risk of CHD morbidity related to the use of calcium supplements. At baseline, 2723 women reported current use of calcium or calcium + D supplementation. During the follow-up, CHD was diagnosed in 513 women. Compared to non-users of calcium/calcium + D supplements, the multivariate adjusted hazard ratio (HR) of CHD was 1.24 (95% CI 1.02–1.52) in women who used these supplements. The multivariate adjusted HR for CHD morbidity in postmenopausal women who used calcium/calcium + D supplements was 1.26 (95% CI 1.01–1.57).

Conclusions

Calcium or calcium + D supplementation appears to increase the risk of CHD among women before old age.     

Typing of SHV extended-spectrum beta-lactamases by pyrosequencing in Klebsiella pneumoniae strains with chromosomal SHV beta-lactamase

In Klebsiella pneumoniae, the cooccurrence of chromosomal and plasmid-mediated beta-lactamases can hinder their accurate molecular detection. We developed a fast and reliable method that allows the typing of isolates carrying more than one SHV gene. The method is based on pyrosequencing the DNA sequence corresponding to amino acid positions 35, 238, and 240.     

How to use bibliometric methods in evaluation of scientific research? An example from Finnish schizophrenia research

We present bibliometric methods that can be utilized in evaluation processes of scientific work. In this paper, we present some practical clues using Finnish schizophrenia research as an example and comparing the research output of different institutions. Bibliometric data and indicators including publication counts, impact factors and received citations were used as tools for evaluating research performance in Finnish schizophrenia research. The articles and citations were searched from the Web of Science database. We used schizophrenia as a keyword and defined address Finland, and limited years to 1996-2005. When we analysed Finnish schizophrenia research, altogether 265 articles met our criteria. There were differences in impact factors and received citations between institutions. The number of annually published Finnish schizophrenia articles has tripled since the mid-1990s. International co-operation was common (43%). Bibliometric methods revealed differences between institutions, indicating that the methods can be applied in research evaluation. The coverage of databases as well as the precision of their search engines can be seen as limitations. Bibliometric methods offer a practical and impartial way to estimate publication profiles of researchers and research groups. According to our experience, these methods can be used as an evaluation instrument in research together with other methods, such as expert opinions and panels.     

The strength of the 6-strand modified Kessler repair performed with triple-stranded or triple-stranded bound suture in a porcine extensor tendon model: an ex vivo study

PURPOSE: To investigate the biomechanic influence of triple-stranded sutures and the spatial arrangement of the strands on the strength of the 6-strand Pennington modified Kessler repair. METHODS: In the present ex vivo study of pig extensor tendons 2 techniques were used: (1) triple-stranded suture (3 suture strands in the same needle) and (2) triple-stranded bound suture (3 suture strands in the same needle that were bound together, parallel to each other, side by side). The repairs were subjected to static tensile testing. RESULTS: The 6-strand modified Kessler repair performed with triple-stranded bound suture reached significantly higher yield force, ultimate force, and both partial and total 1-, 2-, and 3-mm gap forces compared with the repairs performed with triple-stranded suture. The stiffness and strain values at the yield point and at the ultimate point did not differ significantly. CONCLUSIONS: This experimental study introduces a way to improve the strength of the tendon repair. The triple-stranded bound suture significantly increased both the gap resistance and ultimate force of the 6-strand modified Kessler repair. We assume the improvements are due to increased holding capacity of the locking loops. The triple-stranded bound suture is easy to use and avoids several problems associated with traditional multistrand repairs. Further studies are needed before clinical use can be considered.     

Surface-bound bisphosphonates enhance screw fixation in rats--increasing effect up to 8 weeks after insertion

Background A bisphosphonate coating improves screw fixation 2 weeks after implantation in cancellous bone. This study on rats examined further development of fixation over time for screws inserted in cancellous and cortical bone.

Methods SS screws were coated with a multiple layer of fibrinogen. Half of the screws were coated further with bisphosphonates, which were linked to the fibrinogen. The screws were inserted in cancellous and cortical bone in rats. The rats were killed after 5 h, 4 days, 1, 2, 4, 8, and 24 weeks, and fixation was evaluated by pullout test.

Results There was a gradual increase in pull-out force over time in both cancellous and cortical bone. The bisphosphonate coating improved fixation. Moreover, the difference between the bisphosphonate and control groups increased with time. The pull-out force was almost twice that of the controls for screws inserted in cancellous bone at 8 weeks. Energy uptake was increased more than 3-fold.

Discussion The energy uptake and pull-out force of a screw depends on the bone engaged with the threads. Thus, the presence of bisphosphonates increased the amount or quality of this bone by affecting the resorp-tion/formation in a positive way. The increased effect of the bisphosphonates with time thus suggests that bisphosphonate is retained within the remodeling bone, with a positive effect on its gradual adaptation to the implant.     

Edentulism among Finnish adults of working age, 1978–1997

OBJECTIVES: The dental health of Finnish children and young adults has improved considerably during the last 25 years. At the same time, there are still middle-aged or elderly individuals who have lost some or all of their teeth, since extractions were commonly used as a treatment for dental infections during earlier decades. The aim of the present study was to analyze changes of the prevalence of and risk indicators for edentulism among Finnish adults of working age (15-64 years) from 1978 to 1997. METHODS: The National Public Health Institute has, since 1978, conducted annual surveys concerning health behavior among the Finnish adult population. The data were collected through a mailed questionnaire including questions on the number of missing teeth. Sample sizes varied from 5000 to 6000 and the response rates from 70% to 85%. RESULTS: The dental status profile of the Finnish adult population has changed considerably since 1978. The prevalence of edentulism decreased from 14% to 6% during the study years. At the same time, the number of persons with complete dentition increased from 60% to 80%. The decrease in edentulism was obvious in both sexes, but the change was more remarkable among women. In 1997, the difference between the sexes had almost disappeared. The differences between regional and educational groups were still marked in 1997. Belonging to a certain birth cohort appeared to be the major factor affecting the percentage of edentulous subjects. In 1978 risk indicators of total tooth loss included age, gender, length of education, geographical area, urbanization, marital status, and medication for headache. In 1997 risk indicators included age, length of education, geographical area, history of smoking, and perceived status of health. CONCLUSIONS: The number of totally edentulous working-age persons is rapidly decreasing in Finland. Edentulism was strongly associated with birth cohorts and is apparently accumulating in a diminishing group of people. Relevant factors that were strongly associated with edentulousness did not vary considerably between the study years.