Genetics of intervertebral disc disease: A review

Intervertebral disc disease (IVDD) is a common musculoskeletal disease affecting about 5% of all individuals. It is characterized by lumbar disc herniation, which causes nerve root irritation, either mechanically or via inflammatory mediators, and results in radiating pain, known as sciatica. Numerous studies have been conducted to identify the causes and risk factors for IVDD. Lifting heavy loads, torsional stress, and motor vehicle driving are among the best-identified environmental risk factors. However, it has become evident recently from family and twin studies that genetic factors may also be important in IVDD. This hypothesis was strengthened by the identification of two collagen IX alleles associated with sciatica and lumbar disc herniation. In addition, disc degeneration has been shown to be related to an aggrecan gene polymorphism, a Vitamin D receptor and matrix metalloproteinase-3 gene alleles. This review highlights the genetic role and occupational aspects of IVDD.     

Efficacy of the cognitive orientation to daily occupational performance with Brazilian children with developmental coordination disorder

Background: Children with Developmental Coordination Disorder (DCD) have difficulties performing daily activities which reflects negatively on participation, impacting their lives.

Objectives: To examine the effects of the cognitive orientation to daily occupational performance Approach (CO-OP Approach) protocol on occupational performance and satisfaction of Brazilian children who have DCD; to examine whether children could transfer strategies and skills learned during CO-OP to untrained goals.

Methods: A pre-post group comparison design with eight boys aged 6–10 years old. Children participated in 12 CO-OP sessions with their parents twice a week, with an extra session added to the protocol for parents´ orientation. The Canadian Occupational Performance Measure and the Performance Quality Rating Scale were used as outcome measures. The study was registered by the United States Institutes of Health at ClinicalTrials.gov (NCT03112746).

Results: Intervention resulted in higher, clinically and statistically significant, occupational performance measures according to parents, children’s, and external evaluators’ perspectives. All children improved occupational performance on their selected goals and five children could transfer the ability to use cognitive strategies to tasks not addressed in therapy.

Conclusions: This study provides initial directions for future research to investigate the applicability and to implement CO-OP approach on pediatric settings in Brazil.     

Systemic sclerosis and exposure to heavy metals

As a mirror image of the Roman god Janus Bifrons, the environment has a hidden face. To highlight this hidden face of the environment in the field of systemic sclerosis (SSc) will allow to identify responsible agents emerging in the future. To date, there is, in fact, a growing scientific evidence that environmental factors have a crucial impact on both alterations and modulation of epigenetic determinants, resulting in SSc onset and progression. It has been well established that there is a marked correlation between SSc onset and occupational exposure to crystalline silica and organic solvents. More recently, an association between SSc and exposure to heavy metals has further been found, including: antimony, cadmium, lead, mercury. These latter findings interestingly underscore that occupational exposure to heavy metals should be systematically checked in all SSc patients at diagnosis, as the identification of the occupational toxic agent will allow its interruption, which may result in potential improvement of SSc outcome.     

Application of the Draft NIOSH Occupational Exposure Banding Process to Bisphenol A: A case study

Bisphenol A is a commercially important chemical used to make polycarbonate plastic, epoxy resins, and other specialty products. Despite an extensive body of in vitro, animal and human observational studies on the effects of exposure to bisphenol A, no authoritative bodies in the U.S. have adopted or recommended occupational exposure limits for bisphenol A. In 2017, the National Institute for Occupational Safety and Health published a Draft process for assigning health-protective occupational exposure bands, i.e., an airborne concentration range, to chemicals lacking an occupational exposure limit. Occupational exposure banding is a systematic process that uses both quantitative and qualitative toxicity information on selected health effect endpoints to assign an occupational exposure band for a chemical. The Draft process proposes three methodological tiers of increasing complexity for assigning an occupational exposure band. We applied Tier 1 (based on the Globally Harmonized System of Classification and Labelling) and Tier 2 (based on authoritative sources/reviews) to assign an occupational exposure band to bisphenol A. Under both Tier 1 and 2, the occupational exposure band for bisphenol A was “E” (<0.01?mg/m³), an assignment based on eye damage. “E” is the lowest exposure concentration range, reserved for chemicals with high potential toxicity. If eye damage was excluded in assigning an air concentration exposure range, then bisphenol A would band as “D” (>0.01 to 0.1?mg/m³) under Tier 1 (based on reproductive toxicity and respiratory/skin sensitization) and under Tier 2 (based on specific target organ toxicity-repeated exposure). In summary, Tiers 1 and 2 gave the same occupational exposure band for bisphenol A when eye damage was included (“E”) or excluded (“D”) as an endpoint.     

Derivation of internal dose-based thresholds of toxicological concern for occupational inhalation exposure to systemically acting organic chemicals

This study aimed at deriving occupational thresholds of toxicological concern for inhalation exposure to systemically-acting organic chemicals using predicted internal doses. The latter were also used to evaluate the quantitative relationship between occupational exposure limit and internal dose. Three internal dose measures were identified for investigation: (i) the daily area under the venous blood concentration vs. time curve, (ii) the daily rate of the amount of parent chemical metabolized, and (iii) the maximum venous blood concentration at the end of an 8-hr work shift. A dataset of 276 organic chemicals with 8-hr threshold limit values-time-weighted average was compiled along with their molecular structure and Cramer classes (Class I: low toxicity, Class II: intermediate toxicity, Class III: suggestive of significant toxicity). Using a human physiologically-based pharmacokinetic model, the three identified dose metrics were predicted for an 8-hr occupational inhalation exposure to the threshold limit value for each chemical. Distributional analyses of the predicted dose metrics were performed to identify the percentile values corresponding to the occupational thresholds of toxicological concern. Also, simple linear regression analyses were performed to evaluate the relationship between the 8-hr threshold limit value and each of the predicted dose metrics, respectively. No threshold of toxicological concern could be derived for class II due to few chemicals. Based on the daily rate of the amount of parent chemical metabolized, the proposed internal dose-based occupational thresholds of toxicological concern were 5.61?×?10^?2 and 9?×?10^?4 mmol/d at the 10th percentile level for classes I and III, respectively, while they were 4.55?×?10^?1 and 8.5?×?10^?3 mmol/d at the 25th percentile level. Even though high and significant correlations were observed between the 8-hr threshold limit values and the predicted dose metrics, the one with the rate of the amount of chemical metabolized was remarkable regardless of the Cramer class (r² = 0.81; n = 276). The proposed internal dose-based occupational thresholds of toxicological concern are potentially useful for screening-level assessments as well as prioritization within an integrated occupational risk assessment framework.     

Prevalence of Chronic Diseases and Occupational Injuries and their Influence on the Health-Related Quality of Life Among Farmers Working in Small-Farm Enterprises

Objectives: This study aimed to determine the prevalence of chronic diseases and occupational accidents and injuries, and to examine their association with the quality of life among a sample of Iranian farmers.

Methods: A cross-sectional study was conducted among 736 male farmers. Data on the prevalence of chronic diseases and occupational accidents and injuries was collected using an author-developed questionnaire, and the SF-36 questionnaire was used to obtain information on quality of life.

Results: The prevalence of chronic diseases was 96.1%. Musculoskeletal diseases (MSDs), eye diseases and neurology diseases were the most prevalent diseases. Almost half of the farmers (42.7%) had experienced an occupational accident during the last 12 months and cuts and fractures accounted for the most frequent injuries. Sick leave was reported by 28.2% of the farmers and from those with history of accidents, 21.4% were hospitalized. A significant association was found between age and education level with quality of life. Most of the chronic diseases showed a significant and inverse association with quality of life, however, the strongest association was found for MSDs and mental disorders. Furthermore, the most important injury associated with quality of life was cuts and fractures.

Conclusions: Based on the results, MSDs, mental disorders, and cut and fractures were the main determinants of the farmers’ quality of life. Hence, a better quality of life among farmers is especially dependent on eliminating ergonomics risk factors leading to developing musculoskeletal disorders, improving psychosocial work climate, and promoting occupational and personal safety culture.     

The conflicted practice: Municipal occupational therapists’ experiences with assessment of clients with cognitive impairments

Background: The practice of Norwegian occupational therapists (OTs) in municipal practice is a little explored area and with the Coordination Reform Act from 2012, Norwegian OTs in municipal practice have received responsibilities concerning clients with cognitive impairments. The aim of this study was to explore municipal OTs experiences with assessment of clients with cognitive impairments.

Method: Fourteen individual interviews with OTs who worked with clients with cognitive impairments, were conducted. An inductive thematic analysis, using text condensation and coding, was performed.

Results: The results revealed three themes; power of occupation, advantages and disadvantages of assessments used and the need for competencies within municipal services. The participants emphasized using observation in the assessment process and reflected on pros and cons of the standardized assessment tools they used. They expressed a need for competence development, although it was difficult to prioritize to do so.

Conclusion: This study illustrated a conflicted practice related to choices OTs make in their practices. They valued the importance of working occupation based, however, they chose to use impairment based standardized assessments. They expressed a need to engage in professional development, but due to heavy workloads, the limited power they experienced and lack of knowledge, this was difficult.     

Occupational contact dermatitis in a manicurist

We report a case of a manicurist who developed an allergic skin reaction to acrylates, manifested by itchy erythema, papules, vesicles and fissures on her hands, fingertips, forearm and eyelids. Patch tests showed positive reactions to three nail products used: ethylene glycol dimethacrylate, 2‐hydroxyethyl methacrylate, ethyl acrylate and 2‐hydroxyethyl acrylate in (meth)acrylate series. By using gel nail products, our patient became sensitized to 2‐hydroxyethyl methacrylate. We assume that this had been the trigger, leading to the occurrence of cross‐reactions between numerous acrylates including ethylene glycol dimethacrylate, ethyl acrylate and 2‐hydroxyethyl acrylate. When handling nail products, it is necessary to prevent airway sensitization, contact sensitization and cross‐reaction between various acrylates.