Validity of the Capacity to Work Index: Development of an Instrument to Measure Work Capacity in Relation to Depression and Anxiety in the General Working Population.

PURPOSE: To develop an index to assess capacity to work in relation to common mental disorders (CMDs) in the general working population and field test its psychometric properties. METHODS: Content analysis of three qualitative studies on people (n = 49) with their own experiences of working with CMD guided the items selected for the index. Face and content validity and test-retest reliability were performed. The index was field tested in two versions with 26 and 17 items, respectively, among health care professionals regarding internal reliability, component structure and concurrent validity. RESULTS: The final version of the Capacity to Work Index (C2WI; 17 items) was normally distributed in the field test with high internal reliability (Cronbach's alpha, 0.84). Missing responses were randomly distributed and nonspecific. Principal component analysis showed one clear component with negatively framed items. Concurrent validity showed high correlation with the WHO-5 Well-Being Scale (Pearson's r, 0.68), but lower correlation for the general health question (r, - 0.44), one item of the Work Ability Index (r, - 0.33), and the Stress of Conscience constructs (r, 0.44). CONCLUSION: The C2WI showed promising psychometric qualities. Low and negative correlation with the item from Work Ability Index suggests that the C2WI measures additional dimensions, but further testing in larger and more diverse samples is required.

Health status and quality of life among road users with permanent medical impairment several years after the crash.

OBJECTIVE: Improvements in road infrastructure and vehicle safety have been achieved in many countries during the last decades. As the number of fatalities have dropped, the consequences of non-fatal injuries have been brought into focus. Therefore, the objective was to investigate self-reported health status and health-related quality of life several years after the crash for road-users that sustained injuries resulting in permanent medical impairment (PMI). METHODS: A self-administered questionnaire using instruments to measure if health, health-related quality of life and physical activity had been affected by the crash, were used. The injured road-users were identified from insurance policy holders of the Folksam Insurance Group. The response rate was 29%, a total of 2078 responses were received from the 7174 road-users with PMI that received the questionnaire. RESULTS: In total 85% were still suffering from the injuries several years after the crash (8-18 year after the crash). Furthermore, road-users with injuries to the spine were having highest pain intensity. Older road-users had poorer self-reported health status than younger road-users. Although, younger road-users had the greatest change in physical activity when comparing before and after the crash. Before the crash in total 63% were physically active while only 34% after the crash. The higher the PMI the higher it affected health several years after the crash. CONCLUSIONS: The Swedish definition of serious injury, an injury leading to PMI, was found to correlate with self-reported health loss; 85% of the injured road-users reported that they still had remaining symptoms several years after the accident. The injured body region leading to PMI after an accident can vary from the body regions reported to cause long-term health loss. It was found that the higher the degree of PMI the higher the health loss. Sustaining a PMI regardless severity and injured body region has the same effects on general health for men and women. Sustaining a PMI will both lower the health-related quality of life and physical activity after the crash compared to before.

Health and Work Environment among Female and Male Swedish Elementary School Teachers-A Cross-Sectional Study.

BACKGROUND AND OBJECTIVES: Changes in teachers' work situation in Sweden since the 1990s may have contributed to an increase in common mental disorders (CMDs) and burnout. However, there is a lack of research in this field. The aim was to describe how Swedish elementary school teachers experience their health, organizational and social work environment, and the psychosocial safety climate at the workplace, and especially differences and similarities between female and male teachers. MATERIALS AND METHODS: Data were collected with the COPSOQ, OLBI, UWES and PSC-12 from 478 elementary teachers, 81.0% of them women, from twenty schools. The response rate was 96.4%. RESULTS: Teachers reported relatively good general health but experienced high stress, high work pace and emotional demands, low influence at work and a poor psychosocial safety climate. These factors were especially prominent among female teachers. Both women and men experienced good development possibilities and high work engagement. CONCLUSIONS: The results of this study can help us to develop a more sustainable work environment for female and male teachers. A more sustainable work environment might attract more people to the profession and incentivize existing teachers to remain in the profession.

Opportunities for recovery at work and excellent work ability - a cross-sectional population study among young workers.

BACKGROUND: Better opportunities for recovery at work are thought to be associated with work ability in a young workforce but evidence is scarce to lacking. The aim of this study was to examine cross-sectional associations between opportunities for recovery at work and excellent work ability among young workers and specifically for young workers with high work demands. METHODS: A study group of 1295 women and 1056 men aged 18-29 years was selected from three biennial years of a population cohort. The subsample reporting high work demands consisted of 439 women and 349 men. The study group had completed a work environment questionnaire in a survey conducted by Statistics Sweden. Associations between opportunities for recovery at work and excellent work ability were assessed by multiple logistic regression models stratified for gender. RESULTS: Having varied work was associated with excellent work ability in all young men (p < 0.0006; prevalence ratio [PR] 1.3) and also specifically in men with high work demands (p = 0.019; PR 1.3). For the latter group the possibility of deciding when to perform a work task was also associated with excellent work ability (p = 0.049; PR 1.3). Among young women with high work demands, the possibility of deciding one's working hours was associated with excellent work ability (p = 0.046; PR 1.2). CONCLUSIONS: For young men, having varied work can contribute to excellent work ability. In addition, for men with high work demands, the possibility of deciding when to perform a work task may be favourable for excellent work ability. For young women with high work demands, the possibility of deciding one's working hours can contribute to excellent work ability. Employers could use these opportunities for recovery in promoting work ability among young workers.

Experiences of work ability in young workers: an exploratory interview study.

PURPOSE: The aim of this study was to explore the experiences of and influences on work ability in young workers related to their work and life situation. METHODS: In a qualitative study of a strategic sample of 12 young female and 12 young male workers, aged 25-30 years, in work or recently left work, recruited from the 5-year follow-up of a Swedish cohort, semi-structured interviews were performed to explore the experiences of work ability in these young workers. Systematic text condensation inspired by phenomenology was used in the analysis. RESULTS: Work ability was experienced as complex, consisting of four themes, each with three subthemes. To be alert and have energy, to possess sufficient education, skills and working life experience and experience meaningfulness and engagement in work, were perceived to be fundamental for work ability and were seen as the worker's own responsibility. Moreover, work ability can be improved or reduced by the psychosocial work climate, the work organization and the private life. Optimal work ability was experienced when all themes integrated in a positive way. CONCLUSIONS: Work ability was experienced as the worker's own responsibility that could be influenced by work circumstances and private life. To promote good work ability among young workers, work ability has to be understood in its specific context. Whether the understanding of work ability found in this study is explicit for the group of young adults needs to be explored in a more general population in further research.

In-Air and Underwater Hearing in the Great Cormorant (Phalacrocorax carbo sinensis).

Hearing thresholds of a great cormorant (Phalacrocorax carbo) were measured in air and under water using psychophysics. The lowest thresholds were at 2 kHz (45 dB re 20 µPa root-mean-square [rms] in air and 79 dB re 1 µPa rms in water). Auditory brainstem response measurements on one anesthetized bird in air indicated an audiogram with a shape that resembled the one achieved by psychophysics. This study suggests that cormorants have rather poor in-air hearing abilities compared with other similar-size birds. The hearing capabilities in water are better than what would have been expected for a purely in-air adapted ear.

Sealworm (Pseudoterranova decipiens) infection in grey seals (Halichoerus grypus), cod (Gadus morhua) and shorthorn sculpin (Myoxocephalus scorpius) in the Baltic Sea.

The anisakid nematode Pseudoterranova decipiens, known as the sealworm or cod worm, can infect the flesh of several fish species. The parasite causes cosmetic problems for the fish industry and can cause abdominal discomfort if consumed by humans. There are only scattered studies on the abundance or distribution of the sealworm in fish and seals in the Baltic Sea. To remedy this situation, the extent of sealworm infection was investigated in cod (Gadus morhua) and shorthorn sculpin (Myoxocephalus scorpius) collected along the Swedish coast. A relative presence of the sealworm was also investigated in samples from grey seal (Halichoerus grypus) stomachs. Up to 100% of the fish were infected in some of the areas. Sculpin were generally worse infected than cod, both in abundance and prevalence of parasites. General linear models showed a significant correlation between the number of seals in an area and the prevalence of sealworms in cod. There was a sharp decrease of infected fish in areas with salinity lower than 7‰. Even though the northern Baltic proper and the southern Bothnian Sea have a high number of grey seals, only one sealworm was found in a sculpin in that region, and none in cod. In grey seal stomachs the sealworm was only found in samples from the central Baltic proper; further north, all anisakid nematodes identified in seals were Contracaecum osculatum. The results indicate that seal presence drives the distribution in the southern parts of the Baltic and that low salinity, or some other variable which correlates with salinity, limits the distribution in the northern part.

Estimating competition between wildlife and humans-a case of cormorants and coastal fisheries in the Baltic Sea.

Cormorants and other wildlife populations have come in real or perceived conflicts with humans over exploited fish stocks. From gut contents of cormorants, and using an extension of the Catch equation, we estimated the degree of short term competition between great cormorants and coastal fisheries in two areas along the Swedish Baltic Sea. Cormorants consumed 10 and 44%, in respective area, of the fish biomass of six fish species harvested by humans; eel, flounder, herring, perch, pike, and whitefish. On average, cormorants consumed smaller individuals than harvested in fisheries. But for perch, cod and flounder, cormorants consumed harvestable sized fish corresponding >20% of human catches. Our competition model estimated the direct decrease in fisheries catches due to cormorant predation to be <10% for all species except flounder (>30%) and perch (2-20%). When also including the indirect effects of cormorant predation on smaller fish that never reached harvestable size, the estimated decrease in fisheries catches at least doubled for perch (13-34%) and pike (8-19%). Despite large uncertainties, our model indicates that cormorants may locally have a direct impact on human catches of at least flounder, and when incorporating indirect effects also on perch and pike. The study indicates that the degree of competition between cormorants and humans varies substantially between areas. We also included economical values in the model and concluded that for the commercially most important species, eel and cod, the estimated economic impact of cormorants on fisheries was low.

Changes in work situation and work ability in young female and male workers. A prospective cohort study.

BACKGROUND: Good work ability is very important in young workers, but knowledge of work situations that influence work ability in this group is poor. The aim of this study was to assess whether changes in self-reported work factors are associated with self-reported work ability among young female and male workers. METHODS: A sample of 1,311 (718 women and 593 men) was selected from a Swedish cohort of workers aged 21-25 years. At baseline and at 1-year follow-up, participants completed a self-administrated questionnaire including ratings of physical and psychosocial work factors and current work ability. Prevalence ratios were calculated to assess univariate and multivariate associations between changes in work factors and changes in work ability. RESULTS: Decreased job control (PR 1.7, 95% CI 1.49-2.12) and increased negative influence of job demands on private life (PR 1.5, 95% CI 1.25-1.69) were associated with reduced work ability for both female and male workers in the multivariate analyses. Among female workers, an association was found between improved work ability and increased social support at work (PR 2.4, CI 1.43-3.95). For male workers, increased job control (PR 2.3, 95% CI 1.21-4.54) and decreased negative influence of job demands on private life (PR 2.1, 95% CI 1.10-3.87) were associated with improved work ability in the multivariate analyses. CONCLUSIONS: Decreased job control and increased negative influence of job demands on private life over time seem to be the most important work factors associated with reduced work ability among young workers of both sexes. Increased social support at work, increased job control, and decreased negative influence of job demands on private life were also found to be the main work factors associated with improved work ability, although with possible gender differences.

Risk factors for generally reduced productivity--a prospective cohort study of young adults with neck or upper-extremity musculoskeletal symptoms.

OBJECTIVES: This study prospectively assessed the importance of individual conditions and computer use during school or work and leisure time as risk factors for self-reported generally reduced productivity due to musculoskeletal complaints among young adults with musculoskeletal symptoms in the neck or upper extremities. METHODS: A cohort of 2914 young adults (18-25 years, vocational school and college or university students) responded to an internet-based questionnaire concerning musculoskeletal symptoms related to individual conditions and computer use during school or work and leisure time that possibly affected general productivity. Prevalence ratios (PR) were used to assess prospective risk factors for generally reduced productivity. RESULTS: The selected study sample (N=1051) had reported neck or upper-extremity symptoms. At baseline, 280 of them reported reduced productivity. A follow-up of the 771 who reported no reduced productivity was carried out after 1 year. Risk factors for self-reported generally reduced productivity for those followed-up were symptoms in two or three locations or dimensions for the upper back or neck and the shoulders, arms, wrists, or hands [PR 2.30, 95% confidence interval (95% CI) 1.40-3.78], symptoms persisting longer than 90 days in the shoulders, arms, wrists, or hands (PR 2.50, 95% CI 1.12-5.58), current symptoms in the shoulders, arms, wrists, or hands (PR 1.78, 95% CI 1.10-2.90) and computer use 8-14 hours/week during leisure time (PR 2.32, 95% CI 1.20-4.47). A stronger relationship was found if three or four risk factors were present. For women, a relationship was found between generally reduced productivity and widespread and current symptoms in the upper extremities. CONCLUSIONS: The main risk factors for generally reduced productivity due to musculoskeletal symptoms among young adults in this study were chronic symptoms in the upper extremities and widespread symptoms in the neck and upper extremities.

Platelet-derived growth factor-beta receptor activation is essential for fibroblast and pericyte recruitment during cutaneous wound healing.

Connective tissue remodeling provides mammals with a rapid mechanism to repair wounds after injury. Inappropriate activation of this reparative process leads to scarring and fibrosis. Here, we studied the effects of platelet-derived growth factor receptor-beta blockade in vivo using the platelet-derived growth factor receptor (PDGFR)-beta inhibitor imatinib mesylate on tissue repair. After 7 days, healing of wounds was delayed with significantly reduced wound closure and concomitant reduction in myofibroblast frequency, expression of fibronectin ED-A, and collagen type I. Using a collagen type I transgenic reporter mouse, we showed that inhibiting PDGFR-beta activation restricted the distribution of collagen-synthesizing cells to wound margins and dramatically reduced cell proliferation in vivo. By 14 days, treated wounds were fully closed. Blocking PDGFR-beta signaling did not prevent the differentiation of myofibroblasts in vitro but potently inhibited fibroblast proliferation and migration. In addition, PDGFR-beta inhibition in vivo was accompanied by abnormal microvascular morphogenesis reminiscent of that observed in PDGFR-beta-/- mice with significantly reduced immunostaining of the pericyte marker NG2. Imatinib treatment also inhibited pericyte proliferation and migration in vitro. This study highlights the significance of PDGFR-beta signaling for the recruitment, proliferation, and functional activities of fibro-blasts and pericytes during the early phases of wound healing.

Solubility and proteolysis of the Zb-MalE and Zb-MalE31 proteins during overproduction in Escherichia coli.

From the hypothesis that the rate of expression of a nascent polypeptide controls the accumulation of soluble full-length protein, accumulation of the model fusion proteins Zb-MalE and Zb-MalE31, were studied. MalE and MalE31 are two isoforms of the maltose binding protein, differing only in two consecutive amino acids. Parameters controlling the expression rate were the transcription rate, which was controlled by IPTG induction of the lacUV5 promoter and the substrate addition levels during fed-batch cultivation. Results show that the two product proteins appear in both soluble and insoluble fractions during cultivation and are both subjected to proteolysis. However, the accumulation of the soluble form of Zb-MalE31 protein is radically lower, at all conditions, due to the small difference in primary structure. It was shown that both proteolysis and inclusion body formation could be influenced by the selected parameters although a change in feed rate had a considerably higher effect. A high concentration of inducer and a "high" feed rate result in a low accumulation of soluble product, due to a high proteolysis. The concentration of inducer leading to different levels of transcription is, however, an efficient tool to influence inclusion body formation. At low IPTG concentrations (< or = 5 microM), this formation is almost abolished while at a comparatively high concentration (> or = 300 microM) 50% of the total product accumulated was in the form of inclusion bodies.

Effect of substrate feed rate on recombinant protein secretion, degradation and inclusion body formation in Escherichia coli.

The effect of changes in substrate feed rate during fedbatch cultivation was investigated with respect to soluble protein formation and transport of product to the periplasm in Escherichia coli. Production was transcribed from the P(malK) promoter; and the cytoplasmic part of the production was compared with production from the P(lacUV5) promoter. The fusion protein product, Zb-MalE, was at all times accumulated in the soluble protein fraction except during high-feed-rate production in the cytoplasm. This was due to a substantial degree of proteolysis in all production systems, as shown by the degradation pattern of the product. The product was also further subjected to inclusion body formation. Production in the periplasm resulted in accumulation of the full-length protein; and this production system led to a cellular physiology where the stringent response could be avoided. Furthermore, the secretion could be used to abort the diauxic growth phase resulting from use of the P(malK) promoter. At high feed rate, the accumulation of acetic acid, due to overflow metabolism, could furthermore be completely avoided.

Process design for recombinant protein production based on the promoter, PmalK.

P(malK) is induced through activation of MalT, by the formation of maltotriose and cyclic adenosine monophosphate (cAMP). The possibility to influence endogenous inducer levels is used to vary the production rates in specifically designed production protocols. Induction based on a batch process protocol on maltose gives low production rates, as the result of a lack of cAMP, which is shown to be of major importance to fully induce this promoter. Two mechanisms are thus used to influence the levels of maltotriose and/or cAMP formation: (1) catabolite derepression achieved from low glucose concentration and (2) catabolite derepression/inducer exclusion from diauxic growth on glucose/maltose. Fed-batch processes based on limited amounts of glucose result in product accumulation of up to 10% of the total protein. Depending on the feed of limiting glucose, different production profiles are developed. The initial increase in the production rate is due to maltotriose formation from endogenous glycogen degradation while, later in the process, production can be further supported by elevated levels of cAMP, provided the feed rate is sufficiently low. The introduction of maltose after a preceding fed-batch process on glucose can be efficiently used to produce maltotriose in combination with cAMP formation in the event of catabolite derepression. This leads to higher production rates and a further increase in product accumulation of up to 30% of the total protein. The diauxic growth phase resulting from the shift in carbon source can be shortened and even avoided by the design of the preceding feed-rate of glucose. It is postulated that proper design of the inoculum and initial phases of production can reduce basal levels of product formation. With this promoter, the production rate can be as high as 65 units mg(-1) h(-1) and the time to reach a maximal production rate can be designed to take up to 8 h. Furthermore, the duration of the production rate can be as long as 7 h.

Evaluation of inducible promoters on the secretion of a ZZ-proinsulin fusion protein in Escherichia coli.

Four inducible promoters, uspA, uspB, lacUV5 and malK, were evaluated in the expression of the fusion protein ZZ-proinsulin by Escherichia coli. The aim was to select for their effects on the most appropriate expression system (promoter and culture medium) for secretion of ZZ-proinsulin to the periplasmic space and culture medium. All the expression vectors contained the RNase III cleavage site to ensure that the mRNA translation rate remained independent of 5'-untranslated regions thus making promoter strength comparisons more accurate. The highest ZZ-proinsulin secretion yields were 6.2 mg/g of dry cell weight in the periplasmic space and 2.6 mg/g of dry cell weight in the culture medium using the malK promoter. It was also demonstrated that the use of M9 minimal medium favours secretion.