Study of the interrelationships between musculoskeletal disorders and psychosocial risk factors in occupational health and safety technicians.

Objectives. The aim of this work is to examine the presence of musculoskeletal disorders (MSDs) and the exposure to psychosocial risk in a sample of 399 occupational health and safety technicians (OHSTs), deepening the associations between both aspects. Methods. The standardized Nordic questionnaire and the Decore questionnaire were used. Different descriptive and correlational analyses and a multivariate analysis model were carried out. Results. In total, 77.17% of the participants affirmed having suffered some muscle ailments. The most critical psychosocial risk factors are those related to the rewards that the worker obtains for their work, with 54.7% of the technicians in a situation of alert or emergency. It is highlighted that the fact of not feeling professionally valued, working outside working hours, having musculoskeletal discomfort and perceiving a state of poor or fair health increase the global risk index (GRI) score. Conclusions. The study highlights the high exposure of OHSTs to both physical and psychosocial risk factors as well as the significant relationship between these variables. Furthermore, the predictive model shows the variables that best predict the probability of MSDs: gender, training in emerging risks, perceived health and exposure to psychosocial risk.

Prevalence of musculoskeletal problems in laboratory technicians.

Purpose. The aim of this work was to analyze the prevalence of work-related musculoskeletal symptoms in laboratory technicians and their relation to personal and organizational factors, as well as the lack of specific training on work-related risks. Methods. A standardized Nordic questionnaire made for the Spanish population and a survey of sociodemographic variables and organizational aspects were applied to a sample of 460 Spanish laboratory technicians. The statistical analysis was done through R version 3.4.3. Results. Of the sample studied, 84.5% presented some musculoskeletal discomfort, with a higher percentage in women. The probability of having discomfort was eight times higher for those older than 46 years and the most affected part of the body was the neck. The variables that were associated more significantly with the probability to suffer discomfort in the most affected parts of the body (neck, right shoulder and right wrist) were gender, education level, prevention knowledge and seniority. Conclusions. It is necessary to implement plans to train in specific risks according to the activities done by these professionals.

[Major health consequences a rising from the continued use of new electronic devices with visual display units]. / Principales consecuencias para la salud derivadas del uso continuado de nuevos dispositivos electrónicos con PVD.

The exponential advance of information and communication technologies (ICT) in the last decade has led to the increasingly widespread use of new electronic devices (NED) in the workplace. The emergence of new concepts such as telework from home or mobile work (ework) represents a clear example of this phenomenon. However, the benefits resulting from these changes in work dynamics may mask potential occupational risks and impacts on health and safety derived from "nonresponsible" use of new technologies. The objective of this study was to analyze the impact of NED use in the work environment and to point out the resulting health consequences. It has been observed that desktop computers are still the most frequently used devices, except in mobile work environments, where laptops and smartphones are more prevalent. The emerging health problems detected are mainly associated with musculoskeletal, visual and psychosocial disorders. This work demonstrates the need to continue deepening the study of the emerging pathologies associated with new work environments and possible intervention measures.

El avance exponencial de las Tecnologías de la Información y la Comunicación (TIC) en la última década ha propiciado el uso cada vez más extendido de nuevos dispositivos electrónicos (NDE) en el mundo laboral. La aparición de nuevos conceptos como el teletrabajo desde casa o el trabajo móvil (ework) son claros ejemplos de este fenómeno. Los beneficios derivados pueden llegar a enmascarar los posibles riesgos e impactos para la salud respecto a un uso "no responsable". El objetivo de este estudio fue analizar el impacto del uso de los NDE en el entorno laboral y señalar las principales consecuencias para la salud. Se ha observado que el ordenador de sobremesa es aún el dispositivo más utilizado, salvo en entornos de trabajo móvil donde los ordenadores portátiles y los teléfonos inteligentes (smartphones) se posicionan por delante. Los problemas de salud emergentes detectados se asociaron principalmente a trastornos musculoesqueléticos, visuales y psicosociales. Este trabajo evidencia la necesidad de seguir profundizando en el estudio de las patologías emergentes asociadas a los nuevos entornos de trabajo y en las posibles vías de intervención.

Principales consecuencias para la salud derivadas del uso continuado de nuevos dispositivos electrónicos con PVD / Major health consequences a rising from the continued use of new electronic devices with visual display units

El avance exponencial de las Tecnologías de la Información y la Comunicación (TIC) en la última década ha propiciado el uso cada vez más extendido de nuevos dispositivos electrónicos (NDE) en el mundo laboral. La aparición de nuevos conceptos como el teletrabajo desde casa o el trabajo móvil (ework) son claros ejemplos de este fenómeno. Los beneficios derivados pueden llegar a enmascarar los posibles riesgos e impactos para la salud respecto a un uso "no responsable". El objetivo de este estudio fue analizar el impacto del uso de los NDE en el entorno laboral y señalar las principales consecuencias para la salud. Se ha observado que el ordenador de sobremesa es aún el dispositivo más utilizado, salvo en entornos de trabajo móvil donde los ordenadores portátiles y los teléfonos inteligentes (smartphones) se posicionan por delante. Los problemas de salud emergentes detectados se asociaron principalmente a trastornos musculoesqueléticos, visuales y psicosociales. Este trabajo evidencia la necesidad de seguir profundizando en el estudio de las patologías emergentes asociadas a los nuevos entornos de trabajo y en las posibles vías de intervención

The exponential advance of information and communication technologies (ICT) in the last decade has led to the increasingly widespread use of new electronic devices (NED) in the workplace. The emergence of new concepts such as telework from home or mobile work (ework) represents a clear example of this phenomenon. However, the benefits resulting from these changes in work dynamics may mask potential occupational risks and impacts on health and safety derived from "non-responsible" use of new technologies. The objective of this study was to analyze the impact of NED use in the work environment and to point out the resulting health consequences. It has been observed that desktop computers are still the most frequently used devices, except in mobile work environments, where laptops and smartphones are more prevalent. The emerging health problems detected are mainly associated with musculoskeletal, visual and psychosocial disorders. This work demonstrates the need to continue deepening the study of the emerging pathologies associated with new work environments and possible intervention measures

Comparative analysis of different preservation techniques for the storage of Staphylococcus phages aimed for the industrial development of phage-based antimicrobial products.

Bacteriophages have been proven as effective antimicrobial agents in the treatment of infectious diseases and in other biocontrol applications including food preservation and disinfection. The extensive use of bacteriophages requires improved methodologies for medium- and long-term storage as well as for easy shipping. To this aim, we have determined the stability of four Staphylococcus phages (phiIPLA88, phiIPLA35, phiIPLA-RODI and phiIPLA-C1C) with antimicrobial potential at different temperatures (20°C/25°C, 4°C, -20°C, -80°C, -196°C) and during lyophilization (freeze drying) using several stabilizing additives (disaccharides, glycerol, sorbitol and skim milk). Differences between phages were observed at different temperatures (20°C/25°C, 4°C and -20°C), where phages were less stable. At lower temperatures (-80°C and -196°C), all phages showed good viability after 24 months regardless of the stabilizer. Differences between phages were also observed after lyophilization although the addition of skim milk yielded a dry powder with a stable titer after 24 months. As an alternative to facilitate storage and transportation, phage encapsulation has been also explored. Phage phiIPLA-RODI encapsulated in alginate capsules retained high viability when stored at 4°C for 6 months and at 20°C for 1 month. Moreover, the spray-dryer technique allowed obtaining dry powders containing viable encapsulated phages (phiIPLA-RODI and phiIPLA88) in both skim milk and trehalose for 12 months at 4°C. Storage of phages at 20°C was less effective; in fact, phiIPLA88 was stable for at least 12 months in trehalose but not in skim milk, while phiIPLA-RODI was stable only for 6 months in either stabilizer. These results suggest that encapsulated phages might be a suitable way for shipping phages.

Strategies to Encapsulate the Staphylococcus aureus Bacteriophage phiIPLA-RODI.

The antimicrobial properties of bacteriophages make them suitable food biopreservatives. However, such applications require the development of strategies that ensure stability of the phage particles during food processing. In this study, we assess the protective effect of encapsulation of the Staphylococcus aureus bacteriophage phiIPLA-RODI in three kinds of nanovesicles (niosomes, liposomes, and transfersomes). All these systems allowed the successful encapsulation of phage phiIPLA-RODI with an efficiency ranged between 62% and 98%, regardless of the concentration of components (like phospholipids and surfactants) used for vesicle formation. Only niosomes containing 30 mg/mL of surfactants exhibited a slightly lower percentage of encapsulation. Regarding particle size distribution, the values determined for niosomes, liposomes, and transfersomes were 0.82 ± 0.09 µm, 1.66 ± 0.21 µm, and 0.55 ± 0.06 µm, respectively. Importantly, bacteriophage infectivity was maintained during storage for 6 months at 4 °C for all three types of nanovesicles, with the exception of liposomes containing a low concentration of components. In addition, we observed that niosomes partially protected the phage particles from low pH. Thus, while free phiIPLA-RODI was not detectable after 60 min of incubation at pH 4.5, titer of phage encapsulated in niosomes decreased only 2 log units. Overall, our results show that encapsulation represents an appropriate procedure to improve stability and, consequently, antimicrobial efficacy of phages for application in the food processing industry.

Study of the Interactions Between Bacteriophage phiIPLA-RODI and Four Chemical Disinfectants for the Elimination of Staphylococcus aureus Contamination.

Bacteriophages are currently considered as a promising alternative to antibiotics and disinfectants. However, the use of phages in different clinical and industrial settings will involve their exposure to other disinfectants. As a result, the outcome of the phage treatment will depend on two aspects derived from such interactions. On the one hand, the susceptibility of the phage to disinfectants at the concentrations used for disinfection and at lower residual concentrations needs to be determined. Additionally, the existence of synergistic or antagonistic interactions between phages and disinfectants would also affect the potential success of phage biocontrol applications. Here, we tested these effects for the antistaphylococcal phage phiIPLA-RODI by using four different disinfectants: benzalkonium chloride, triclosan, chlorhexidine and hydrogen peroxide. Our results highlight the differences between disinfectants regarding their effect on phage survival and antimicrobial properties. For instance, our data suggests that, out of the four disinfectants used, benzalkonium chloride would be the most adequate to use in settings where phages are to be applied. Nonetheless, this preliminary analysis grants the need for further studies with a larger number of disinfectants for the development of a phiIPLA-RODI-based product.

Optimizing Propagation of Staphylococcus aureus Infecting Bacteriophage vB_SauM-phiIPLA-RODI on Staphylococcus xylosus Using Response Surface Methodology.

The use of bacteriophages for killing pathogenic bacteria is a feasible alternative to antibiotics and disinfectants. To obtain the large quantities of phages required for this application, large-scale production of bacteriophages must be optimized. This study aims to define conditions that maximize the phage yield of the virulent and polyvalent staphylococcal bacteriophage vB_SauM-phiIPLA-RODI in broth culture, using the food-grade species Staphylococcus xylosus as the host strain to reduce the risk of growing massive quantities of pathogenic bacteria and therefore, to ensure the safety of the final phage stock. The effect of four variables, namely initial bacterial concentration (5.66-8.40 log10 colony-forming unit (CFU)/mL), initial phage concentration (5-8 log10 plaque-forming unit (PFU)/mL), temperature (21-40 °C) and agitation (20-250 rpm), on phage yield (response) was studied by using response surface methodology (RSM). Successive experimental designs showed that agitation did not significantly impact phage yield, while temperature did have a significant effect, with 38 °C being the optimum for phage propagation. The results allowed the design of a model to describe phage yield as a function of the initial bacterial and phage concentrations at fixed agitation (135 rpm), and optimum temperature (38 °C). The maximum experimental phage yield obtained was 9.3 log10 PFU/mL, while that predicted by the model under the optimized conditions (7.07 log10 CFU/mL initial bacterial population and 6.00 log10 PFU/mL initial phage titer) was 9.25 ± 0.30 log10 PFU/mL, with the desirability of 0.96. This yield is comparable to that obtained when the phage was propagated on the original host, Staphylococcus aureus. Bacteriophage phiIPLA-RODI showed the same host range and very similar biofilm removal ability regardless of the staphylococcal species used for its propagation. The results presented in this study show the suitability of using a food-grade strain of S. xylosus for the propagation of S. aureus infecting phages and the application of RSM to define the optimal propagation conditions.