Contribution of nerves within osteochondral channels to osteoarthritis knee pain in humans and rats

© 2020 Osteoarthritis Research Society International Objectives: Subchondral bone may contribute to knee osteoarthritis (OA) pain. Nerve growth factor (NGF) can stimulate nerve growth through TrkA. We aimed to identify how sensory nerve growth at the osteochondral junction in human and rat knees associates with OA pain. Methods: Eleven symptomatic chondropathy cases were selected from people undergoing total knee replacement for OA. Twelve asymptomatic chondropathy cases who had not presented with knee pain were selected post-mortem. OA was induced in rat knees by meniscal transection (MNX) and sham-operated rats were used as controls. Twice-daily oral doses (30 mg/kg) of TrkA inhibitor (AR786) or vehicle were administered from before and up to 28 days after OA induction. Joints were analysed for macroscopic appearances of articular surfaces, OA histopathology and calcitonin gene-related peptide-immunoreactive (CGRP-IR) sensory nerves in medial tibial plateaux, and rats were assessed for pain behaviors. Results: The percentage of osteochondral channels containing CGRP-IR nerves in symptomatic chondropathy was higher than in asymptomatic chondropathy (difference: 2.5% [95% CI: 1.1–3.7]), and in MNX-than in sham-operated rat knees (difference: 7.8% [95%CI: 1.7–15.0]). Osteochondral CGRP-IR innervation was significantly associated with pain behavior in rats. Treatment with AR786 prevented the increase in CGRP-IR nerves in osteochondral channels and reduced pain behavior in MNX-operated rats. Structural OA was not significantly affected by AR786 treatment. Conclusions: CGRP-IR sensory nerves within osteochondral channels are associated with pain in human and rat knee OA. Reduced pathological innervation of the osteochondral junction might contribute to analgesic effects of reduced NGF activity achieved by blocking TrkA

The association of painful and non-painful morbidities with frailty: a cross sectional analysis of a cohort of community dwelling older people in England

IntroductionThe association between chronic pain and frailty might indicate that pain is an independent driver of frailty but might alternatively be explained by inclusion within frailty identification tools of morbidities that commonly lead to chronic pain. This research examines the extent to which the association of pain with frailty might be attributed to morbidities.MethodsA cross-sectional analysis of older people in a UK cohort with or at risk of musculoskeletal problems or frailty (Investigating Musculoskeletal Health and Wellbeing study), used multivariable logistic regression and Z-tests to assess the degrees of associations of pain (McGill Pain Rating Index), and painful and non-painful morbidity counts with frailty (modified FRAIL questionnaire).ResultsData were from 2,185 participants, 56% female, median age 73 (range 60 to 96) years. 430 (20%) participants were classified as frail. In a fully adjusted standardised model, pain (aOR 2.07 (95%CI 1.83 to 2.33) and ‘any’ morbidity aOR (1.74 (95%CI 1.54 to 1.97) were both significantly associated with frailty. When morbidity was subclassified as painful or non-painful, painful (aOR 1.48 (95%CI 1.30 to 1.68) and non-painful (aOR1.39 (95%CI 1.24 to 1.56)) morbidities each were associated with frailty, as also was pain (aOR 2.07 (95%CI 1.83 to 2.34, p < 0.001).ConclusionsPain is associated with frailty, over and above any effect of painful and non-painful morbidities. This forms the justification for future research which focuses on pain management in the identification, prevention, and treatment of frailty

Clinical and Preclinical Evidence for Roles of Soluble Epoxide Hydrolase in Osteoarthritis Knee Pain

Objective: Chronic pain due to osteoarthritis (OA) is a major clinical problem, and existing analgesics often have limited beneficial effects and/or adverse effects, necessitating the development of novel therapies. Epoxyeicosatrienoic acids (EETs) are endogenous antiinflammatory mediators, rapidly metabolized by soluble epoxide hydrolase (EH) to dihydroxyeicosatrienoic acids (DHETs). We undertook this study to assess whether soluble EH–driven metabolism of EETs to DHETs plays a critical role in chronic joint pain associated with OA and provides a new target for treatment. Methods: Potential associations of chronic knee pain with single-nucleotide polymorphisms (SNPs) in the gene-encoding soluble EH and with circulating levels of EETs and DHETs were investigated in human subjects. A surgically induced murine model of OA was used to determine the effects of both acute and chronic selective inhibition of soluble EH by N-[1-(1-oxopropy)-4-piperidinyl]-N′-(trifluoromethoxy)phenyl]-urea (TPPU) on weight-bearing asymmetry, hind paw withdrawal thresholds, joint histology, and circulating concentrations of EETs and DHETs. Results: In human subjects with chronic knee pain, 3 pain measures were associated with SNPs of the soluble EH gene EPHX2, and in 2 separate cohorts of subjects, circulating levels of EETs and DHETs were also associated with 3 pain measures. In the murine OA model, systemic administration of TPPU both acutely and chronically reversed established pain behaviors and decreased circulating levels of 8,9-DHET and 14,15-DHET. EET levels were unchanged by TPPU administration. Conclusion: Our novel findings support a role of soluble EH in OA pain and suggest that inhibition of soluble EH and protection of endogenous EETs from catabolism represents a potential new therapeutic target for OA pain

PRECONCENTRATION OF CADMIUM USING AMBERLITE XAD-4 PRIOR TO ATOMIC ABSORPTION SPECTROMETERY

Cadmium is an important environmental constituent widely used in industrial processes for production of synthetic materials and therefore can be released in the environment causing public exposure especially around the industrial residence area. For evaluation of human exposure to trace toxic metal of Cd (II), environmental and biological monitoring are essential processes, in which, preparation of such samples is one of the most time-consuming and error-prone aspects prior to analysis. The use of solid-phase extraction (SPE) has grown and is a fertile technique of sample preparation as it provides better results than those produced by liquid-liquid extraction (LLE). To evaluate factors influencing quantitative analysis scheme of cadmium in water samples, solid phase extraction using mini columns filled with XAD-4 resin was optimized with regard to sample pH, ligand concentration, loading flow rate, elution solvent, sample volume (up to 500 ml), elution volume, amount of resins, and sample matrix interferences. Cadmium was retained on solid sorbent and eluted followed by simple determination of analytes by using flame atomic absorption spectrometery. Obtained recoveries of the metal ion were more than 92%. The amount of the analyte detected after simultaneous preconcentration was basically in agreement with the added amounts. The optimized procedure was also validated with three different pools of spiked urine samples and showed a good reproducibility over six consecutive days as well as six within-day experiments. The developed method promised to be applicable for evaluation of other metal ions present in different environmental and occupational samples as suitable results were obtained for relative standard deviation (less than 10%); therefore, it is concluded that, this optimized method can be considered to be successful in simplifying sample preparation for trace residue analysis of Cd in different matrices for evaluation of occupational and environmental exposures

Survey of Correlation between Two Evaluation Method of Work Related Musculoskeletal Disorders Risk Factors REBA& RULA

Background and aims   Musculoskeletal disorder is one of the biggest occupational health problems in workplaces of industries. According to the national statistics, the proportion of musculoskeletal diseases of all occupation diseases in the United States is 44% (Bureau of Labor Statistics, 1996). On the basis of report of National Institute Occupational Safety and Health of USA(NIOSH), WMSDs is in the second place between the work-related diseases. Poor working  postures constitute one of the main risk factors for musculoskeletal disorders. Recognition,  evaluation and control action for prevention of occur disorders is important to protect and  promotion of workers health. For evaluation of WMSDs risk factor, various methods have been  presented. Two practical methods for analyzing and controlling poor working postures in  workplaces are REBA and RULA.   Methods   This research is a cross-sectional study that was conducted in order to survey of  correlation between two evaluation methods of WMSDs risk factors REBA& RULAin one of the ophthalmic lens manufacture factory.At first, jobs were surveyed and all subtasks of jobs recognized and 40 jobs out of 77 were selected. Then REBA& RULAmethods were carried out  for this jobs. Also, The final scores and action levels were determined.   Results   The result revealed that: there was a significant correlation between final score of two  methods (r = 0.781) and action levels of two methods (r=0.821). Compare to action levels, two  methods in all jobs showed that There was no significant difference between action levels at jobs  (p = 0.16) also between action levels of two methods in any of workplaces separately.  Result of REBA& RULAmethods revealed that risk level of lower arm, upper arm and wrist was  higher than trunk, neck, and legs because of awkward posture of the mentioned parts. Result of  RULAand REBAtechnique indicated that, action levels of all jobs were not acceptable.   Conclusion   On the basis of mentioned result above, this study indicated that, there was no  significant correlation between two methods and methods have a strong correlation in identifying  critical work site and determining critical limb. Therefore, both methods are recommended for   evaluation of work-related musculoskeletal disorders risk factors in industrie

Presence of Atrazine in the Biological Samples of Cattle and Its Consequence Adversity in Human Health

Background: Cattle can be considered as an important source for herbicides through nutrition. Therefore, herbicide residue in animal products is a potential human exposure to herbicides causing public health problems in human life. Triazines are a group of herbicides primarily used to control broadleaf weeds in corn and other feed ingredients and are considered as possible human carcinogens. To evaluate trace residue of these pollutants molecular imprinted solid phase extraction (MISPE) method has been developed, using biological samples.Methods: Blood samples were taken from the jugular vein of 45 Holstein cows in 3 commercial dairy farms in Khuzestan Province, Iran. Urine samples were also taken from the cows.Results: The mean ± SD concentrations of atrazine in serum and urine samples of the study group (0.739 ± 0.567 ppm and 1.389 ± 0.633 ppm, respectively) were higher (P < 0.05) than the concentrations in serum and urine samples of the control group (0.002 ± 0.005 ppm and 0.012 ± 0.026 ppm, respectively).Conclusion: Atrazine in the feed ingredients ingested by cattle could be transferred into the biological samples and conse­quently can be considered as a potential hazard for the public health

Trace Analysis of Xylene in Occupational Exposures Monitoring

&quot;nBackground: Determination of organic pollutants usually requires extraction of the pollutants from samples, using hazard&amp;shy;ous solvent. Solid phase micro-extraction (SPME) is a solvent-free equilibrium extraction method, in which, proper calibra&amp;shy;tion can allow quantitative measurements of organic pollutants at a very good sensitivity without the use of any organic sol&amp;shy;vent. Because individual VOCs are generally present in urine only at trace levels, a sensitive and accurate determination technique is essential.&quot;nMethods: This study describes the optimization of headspace solid phase micro-extraction (HS-SPME) followed by gas chromatography equipped with flame ionization detector (GC-FID) for xylene in spiked urine. Through this investigation, the parameters affecting the extraction and GC determination of xylene, including extraction time, temperature, desorption temperature, desorption time, salt addition, sample pH, sample volume and sample agitation were studied.&quot;nResults: An op&amp;shy;timized headspace extraction was carried out at 30&amp;deg;C for 6 min in presence of 0.2 gml-1 of NaCl in the sample solution. De&amp;shy;sorption of the xylene was carried out for 60 sec. at 250&amp;deg;C. The optimized procedure was also validated with three different pools of spiked urine samples and showed a good reproducibility over six consecutive days as well as six within-day ex&amp;shy;periments. In this study, the accuracy, linearity, and detection limits were also determined.&quot;nConclusion: The HS-SPME-GC-FID technique provided a relatively simple, convenient, practical procedure, which can be successfully applied for determination of xylene in spiked urine when an occupational exposure monitoring is required

"Evaluation of Risk Factors Causing Musculoskeletal Disorders Using QEC Method in a Furniture Producing Unite"

The musculoskeletal disorders cover a large percent of occupational diseases; therefore, in order to protect workers from such disorders, there is a need to evaluate workers positions at work in different industries. In a major furniture manufacture located in Tehran, 500 workers were examined. These workers were divided into fourteen working groups, including production lines of water-heater, air condition, electromotor production line, dunnage making hall, plastic hall, smithery, restaurant, store, engineers and supervisors, facilities, transportation, assembly of absorptive refrigerator and drivers. The results from Nordic Questionnaire and performing the evaluation method showed that, there was a significant relevance between outbreak of back pain and workgroups (P=0.005) and between the outbreak of pain in neck and workgroup as well. A significant relevance of P=0.005 indicating that, the working in the above mentioned work-place causes pain in both back and neck. Between other parts of the body and workgroup no significant relevance observed. Among workgroups, there was a significant relevance between the water-heater production line (P&lt;0.005) and pain in the back, and there was also a significant relevance among the work in air–conditioning production line and the plastic injection (P=0.002), causing pain in the neck. The results from Quick Exposure Check (QEC) in one hundred working posture have shown that 10% of them fall into first and second level and 90% of them were categorized in third and forth levels

"EVALUATION OF MUSCULOSKELETAL DISORDERS RISK FACTORS AMONG THE CREW OF THE IRANIAN PORTS AND SHIPPING ORGANIZATION’S VESSELS"

Musculoskeletal disorders (MSDs) are important causes of work incapacity and loss of work days. MSDs are major problems in almost all countries and increasingly can be found in service industries such as maritime sector. This study aimed at evaluation of MSDs symptoms among crew of tugboats, dredgers, pilot boats and barges by using Nordic Musculoskeletal Questionnaire (NMQ) and also determination of work-related MSDs risk factors by application of Ovako Working Analysis Posture System (OWAS). The result showed that 28.4% of body postures rated in action category 3 and 4 of OWAS. It seems that OWAS cannot be used as a determination method of risk factors for all jobs. Also, the best and sometimes the only way to correct awkward postures is correction of worker&apos;s back position