Double Porphyrin Cage Compounds.

The synthesis and characterization of double porphyrin cage compounds are described. They consist of two porphyrins that are each attached to a diphenylglycoluril-based clip molecule via four ethyleneoxy spacers, and are linked together by a single alkyl chain using "click"-chemistry. Following a newly developed multistep synthesis procedure we report three of these double porphyrin cages, linked by spacers of different lengths, i.e. 3, 5, and 11 carbon atoms. The structures of the double porphyrin cages were fully characterized by NMR, which revealed that they consist of mixtures of two diastereoisomers. Their zinc derivatives are capable of forming sandwich-like complexes with the ditopic ligand 1,4-diazabicyclo[2,2,2]octane (dabco).

Interactions of aggregating peptides probed by IR-UV action spectroscopy.

Peptide aggregation, the self-assembly of peptides into structured beta-sheet fibril structures, is driven by a combination of intra- and intermolecular interactions. Here, the interplay between intramolecular and formed inter-sheet hydrogen bonds and the effect of dispersion interactions on the formation of neutral, isolated, peptide dimers is studied using infrared action spectroscopy. Therefore, four different homo- and heterogenous dimers resulting from three different alanine-based model peptides have been formed under controlled and isolated conditions. The peptides differ from one another by the presence and location of a UV chromophore containing end cap. The conformations of the monomers of the peptides direct the final dimer structure: strongly bonded or folded structures result in weakly bound dimers. Here, intramolecular hydrogen bonds are favored over new intermolecular hydrogen bond interactions. In contrast, linear monomers are the ideal template to form parallel beta-sheet type structures. The weak intramolecular hydrogen bonds present in the linear monomers are replaced by the stronger inter-sheet hydrogen bond interactions. The influence of π-π dispersion interactions on the structure of the dimers is minimal, and the phenyl rings have a tendency to fold away from the peptide backbone to favour intermolecular hydrogen bond interactions over dispersion interactions. Quantum chemical calculations confirm our experimental observations.

Effects of office innovation on office workers' health and performance.

The implementation of an innovative office concept (e.g. open-plan, flexible workplaces and a paperless office concept) on health and productivity among office workers was evaluated with questionnaires of 138 workers at baseline and 6 and 15 months afterwards. Work-related fatigue, general health, change in health status, upper extremity complaints and perceived productivity were outcomes. No short-term significant differences were found in most outcomes except for quantity of performed work (decrease from 96% to 92%, p = 0.008). In the long-term, no significant differences were found in most outcomes except for an increase in general health (p = 0.011) and a decrease in prevalences of upper extremity complaints (33% to 22%, p = 0.021). Perceived productivity increased significantly 15 months after the implementation. It is concluded that innovative office concepts had no or limited effects on work-related fatigue, health changes and productivity but some positive effects on workers' general health and upper extremity complaints in the long term. Office innovation is being administered often but up to now seldom evaluated on workers' health and productivity.

Is workstyle a mediating factor for pain in the upper extremity over time?

INTRODUCTION: Upper extremity musculoskeletal disorders influence workers' quality of life. Workstyle may be one factor to deal with in workers with pain in the upper extremity. The objective of this study was to determine if workstyle is a mediating factor for upper extremity pain in a changing work environment of office workers over time. METHODS: Office workers with upper extremity pain filled out a Workstyle questionnaire (WSF) at baseline (n = 110). After 8 and 12 months follow-up assessment took place. Participants were divided into a good and an adverse workstyle group at baseline. The presence of upper extremity pain in both groups was calculated and relative risks were determined. Chi-square tests were used. RESULTS: Eight months after baseline, 80% of the adverse and 45% of the good workstyle group reported pain. The relative risk (RR) of having upper extremity pain for the adverse compared to the good workstyle group was 1.8 (95% CI 1.08-2.86) (P = 0.055). Twelve months after baseline, upper extremity pain was more often presented in the adverse workstyle compared to the good workstyle group (RR = 3.0, (95% CI 1.76-5.11), P = 0.003). Twelve months after baseline, 100% of the adverse workstyle group and 33% of the good workstyle group reported pain in the upper extremity. CONCLUSION: Workstyle seems to be a mediating factor for upper extremity pain in office workers in a changing work environment. It is recommended to assess workstyle among office workers with upper extremity pain, and to include workstyle behaviour in treatments.

What do referred patients with upper extremity musculoskeletal disorders expect of a multidisciplinary treatment and what is the perceived value?

PURPOSE: To describe reasons for not starting and to determine expectations and perceived value of multidisciplinary treatment among referred patients, sick-listed due to upper extremity musculoskeletal disorders METHOD: Twenty-six randomly chosen referred patients who did not start the treatment were interviewed by telephone to identify their reasons for not starting and 24 randomly chosen patients who participated in the treatment were interviewed face-to-face to explore their expectations and experiences of multidisciplinary treatment. RESULTS: Reasons for not starting the treatment are mainly intrinsic to the treatment. The most important reason was that the treatment was thought to be too psychological in nature. Most treated patients had no prior expectations but saw it as a last resort for their complaints. The psychological (cognitive-behavioural) component was perceived as the most useful part that acquired the ability to cope with their complaints and developed an increased self-awareness. Most treated patients are satisfied, although some said the treatment did not meet their expectations, because their complaints had not disappeared. CONCLUSION: The most important reason for not starting the treatment was the assumption that the treatment is too psychological in nature, while in treated patients the psychological sessions were perceived as most useful treatment component.

Effects of a thermal-insulating mouse pad on temperature of forearm and hand during computer tasks.

This laboratory experiment studied the effects of a thermal-insulating mouse pad on arm temperature and comfort during computer work. Fourteen subjects performed two 20-min computer tasks (a mouse task and a combined task alternating keyboard and mouse use), under three conditions, namely with: 1) a thermal-insulating pad; 2) a placebo pad; 3) no pad (desktop). The temperatures of the forearm, wrist, hand and fingers were measured with four thermocouples. Comfort and discomfort were determined by two visual analogue scales. No arm temperature differences were found between the experimental conditions after performing the combination task in any location. After the mouse task, however, arm temperature decreased significantly less with the thermal-insulating mouse pad than with the placebo pad. The thermal-insulating pad was rated as more comfortable and less uncomfortable than a regular desktop during mouse tasks. A large size is recommended for the thermal-insulating pad.

Cost-effectiveness of multidisciplinary treatment in sick-listed patients with upper extremity musculoskeletal disorders: a randomized, controlled trial with one-year follow-up.

OBJECTIVE: To determine the effectiveness and cost-effectiveness of a return-to-work outpatient multidisciplinary treatment programme for sick-listed workers with non-specific upper extremity musculoskeletal complaints. METHODS: A randomized controlled trial with a 1-year follow-up was carried out. Thirty-eight subjects were allocated to multidisciplinary treatment (intervention, n=23), or to usual care provided by occupational health services (n=15). The intervention consisted of psychological and physical sessions provided by a medical specialist, a psychologist, a physiotherapist and an occupational therapist. It aims at reconditioning, "de-medicalizing", unrestrained moving and return-to-work. The intervention process was evaluated on compliance to the protocol and the effectiveness of its components. The individual outcome variable was the severity of complaints. The societal outcomes included return-to-work and costs. Measurements were performed at baseline and after 2, 6 and 12 months. Mixed model analyses were used for analysis. RESULTS: The intervention achieves its aims: physical disabilities (P=0.039), kinesiophobia (P<0.001) and physical functioning (P=0.016) improved significantly as compared to usual care. In addition, the intervention was significantly more effective in reducing the severity of complaints than usual care. The intervention was equally effective compared to usual care in terms of return-to-work (86% in the intervention group vs. 73% in the usual care group). The extra total costs and the extra gains in terms of return-to-work were not significantly higher for the intervention as compared to usual care after 12 months. CONCLUSION: Multidisciplinary treatment affects individuals positively, but shows no significant difference in (cost-) effectiveness on the societal level as compared to usual care.

What is known about temperature and complaints in the upper extremity? A systematic review in the VDU work environment.

UNLABELLED: Upper extremity musculoskeletal complaints and disorders are frequently reported among visual display units (VDU) workers. These complaints include cold forearms, hands or fingers. OBJECTIVE: The aim of this systematic review was to gain an insight into the relationship between objective and subjective temperature decrease and musculoskeletal disorders (MSDs) in the upper extremity in a VDU work environment by (internal or external) cooling of the arm and hand. Two questions were formulated: (1) Is a VDU work environment (temperature between 15 and 25 degrees C) associated with temperature decrease of the arm, hand or fingers in healthy subjects? (2) Is there a difference in arm, hand and finger temperature between patients with upper extremity MSDs and healthy subjects in a VDU work environment? METHODS: Through a systematic literature search in six databases between 1989 and October 2005, 327 articles were retrieved and 17 included. RESULTS: Forearm, hand and finger temperature significantly decreases when the ambient temperature (between 15 and 25 degrees C) decreases. The skin temperature in the hand that uses a computer mouse is lower than the other hand in the same ambient temperature. At baseline, no objective temperature differences are found between patient groups and controls, whereas in patients with cold hand complaints, lower skin temperatures are found compared to controls. The association between temperature (changes) in the forearm, hand or fingers during VDU work, and MSDs in the upper extremity is not clear. CONCLUSION: There is no consistent evidence available for the association between upper extremity MSDs and temperature changes in forearm, hand or fingers in an office work environment.

Evaluation of effective return-to-work treatment programs for sick-listed patients with non-specific musculoskeletal complaints: a systematic review.

OBJECTIVE: This systematic review seeks to gain insight into the effectiveness of return-to-work treatment programs among sick-listed patients with non-specific musculoskeletal complaints. The focus here lies on the composition of effective treatment programs, itemized for regional non-specific musculoskeletal complaints. METHODS: A systematic literature search was performed and methodological quality criteria were applied. RESULTS: Eighteen high quality articles were selected, which reported on a combined total of 22 treatment programs, including a total of 3,579 participants. Of these 22 treatments programs, seven experimental treatments (32%) resulted in faster return to work compared to the control treatment. None of the studies reviewed reported negative findings. What appeared to be essential to effective treatment was knowledge conditioning, psychological, physical and work conditioning, possibly supplemented with relaxation exercises. Most of the high quality studies (64%) reported on a low back pain population. CONCLUSION: The findings were inconsistent regarding the effectiveness of treatment programs in enabling sick-listed patients with non-specific musculoskeletal disorders to return to work. Except for low back pain, none of the studies explicitly itemized the effects of treatment programs on return to work by regional musculoskeletal disorders, such as upper extremity musculoskeletal disorders.