Combined Effects Of Vibration Research Articles

Describing the Cellular Impact of IQOS™ Smoke Extract and Vibration on Human Vocal Fold Fibroblasts

ObjectivesThe isolated or combined effects of vibration and smoke extract (SE) from the IQOS™ “heat-not-burn” technology on human vocal fold fibroblasts (hVFF) were evaluated in an in vitro setting in order to elucidate their influence on vocal fold (patho-) physiology. Study DesignExperimental pilot study using intervention with IQOS™-SE in vitro. MethodsImmortalized hVFF were exposed to IQOS™-SE or control medium under static or vibrational conditions. A phonomimetic bioreactor was used to deliver vibrational patterns to hVFF over a period of 5 days. Cytotoxicity was quantified by lactate dehydrogenase assay. Effects on extracellular matrix production, inflammation, fibrogenesis, and angiogenesis were assessed by reverse transcription-quantitative polymerase chain reaction, Western Blot, enzyme-linked immunosorbent assay, and Magnetic Luminex assays. ResultsWe observed significant changes induced either by IQOS™-SE exposure alone (matrix metalloproteinase 1, fibronectin, cyclooxygenase (COX)1, interleukin-8 gene expression), or by the combination of IQOS™-SE and vibration (hyaluronidase 2, COX2, interleukin-8 protein levels, vascular endothelial growth factor D). ConclusionShort-term in vitro exposure of hVFF to IQOS™-SE did not result in cytotoxicity and reduced the gene expression of measured inflammation mediators, but had no effect on their protein expression. However, the clinical effects of long-term IQOS™ use are still not known and further research is needed in order to asses, if IQOS™ is in fact less harmful than conventional cigarettes.

Experimental study on effects of sound on vibratory sensation of horizontal vibration

Humans are exposed to both vibration and noise when riding in vehicles such as cars and trains. Therefore, an evaluation of the vibratory sensation based on the combined effect of vibration and noise is needed. This study aims to determine the effects of sound on whole-body vibratory sensations of horizontal vibration. In this study, we conducted two experiments to research the influence of sound on vibratory sensation using an electrodynamic vibration test machine. The first experiment measured the point of subjective equality of the magnitudes of vibration and sound, and the second experiment measured the psychological effects of sound on vibratory sensations using the magnitude estimation method and the seven-grade rating scale method. This paper describes the results of investigating vibration dominance in a combined environment of vibration and sound and the effects of sound on the subjective magnitude of vibration and vibration discomfort.

Computational simulation of applying mechanical vibration to mesenchymal stem cell for mechanical modulation toward bone tissue engineering.

Evaluation of cell response to mechanical stimuli at in vitro conditions is known as one of the important issues for modulating cell behavior. Mechanical stimuli, including mechanical vibration and oscillatory fluid flow, act as important biophysical signals for the mechanical modulation of stem cells. In the present study, mesenchymal stem cell (MSC) consists of cytoplasm, nucleus, actin, and microtubule. Also, integrin and primary cilium were considered as mechanoreceptors. In this study, the combined effect of vibration and oscillatory fluid flow on the cell and its components were investigated using numerical modeling. The results of the FEM and FSI model showed that the cell response (stress and strain values) at the frequency of mechanical vibration has the highest value. The achieved results on shear stress caused by the fluid flow on the cell showed that the cell experiences shear stress in the range of . Mechanoreceptors that bind separately to the cell surface, can be highly stimulated by hydrodynamic pressure and, therefore, can play a role in the mechanical modulation of MSCs at in vitro conditions. The results of this research can be effective in future studies to optimize the conditions of mechanical stimuli applied to the cell culture medium and to determine the mechanisms involved in mechanotransduction.

Selecting informative biomarkers for early diagnosis of occupational neurological diseases

Introduction. At present, the patterns of changes in the levels of biomarkers and the relationship of changes in their values with the pathogenesis of diseases caused by the impact of adverse factors of labour activity are not sufficiently studied. The most unresolved issues are the choice of informative laboratory indicators and diagnostic test systems in investigating the impact of physical factors on the working environment (vibration and physical overload) neurohumoral regulation: pituitary-adrenal pituitary-thyroid, pituitary-gonadal system and hormonal indicators of carbohydrate metabolism. The aim of the study was to determine diagnostic hormonal markers and integral indices to identify early changes in the neurohumoral status in the body of workers under the influence of working environment factors. Materials and methods. 330 workers of mining and machine-building enterprises were examined. Of these, 128 people with vibration disease, 45 people - with lumbosacral radiculopathy, combined pathology (vibration disease and lumbosacral radiculopathy) was detected in 60 persons. The preclinical stage (initial signs of diseases) was noted in 97 workers. Laboratory studies included hormones and integral indices of the pituitary-adrenal, pituitary-thyroid, pituitary-gonadal system, carbohydrate metabolism. To select the diagnostic significance of laboratory biomarkers, diagnostic sensitivity, prenosological value, pathognomonicity, direction, severity, and selectivity of changes in biomarker levels were evaluated. Results. The combined effect of vibration and physical overload on the body of workers was found to have a unidirectional and systemic impact on the levels of hormones of the pituitary-adrenal, pituitary-thyroid and pituitary-gonadal systems, increases insulin resistance. The severity of changes in neurohumoral regulation indicators depends on the nature and severity of the occupational neurological disease. The highest diagnostic sensitivity (Df = 72-74%) in vibration disease and its combination with lumbosacral radiculopathy was obtained for pituitary-gonadal hormones and indicators of insulin resistance. The lowest values of Dh are typical for the hormones of the pituitary-thyroid system (no more than 14%). To identify early changes in neurohumoral regulation in the body under the influence of vibration and physical exertion, it is most informative to determine the concentration of total testosterone, luteinizing hormone and insulin, as well as the integral pituitary-adrenal index, insulin resistance indices. To identify hidden disorders of the pituitary-thyroid system, the definition of the essential thyroid index can be used. Discussion. The results obtained allowed us to assess the nature of changes in the levels of hormones of the pituitary-adrenal, pituitary-thyroid and pituitary-gonadal systems and carbohydrate metabolism and to propose informative laboratory biomarkers reflecting early changes in neurohumoral regulation under the influence of physical factors of the working environment. Conclusions. To identify early changes in neurohumoral regulation in the body of workers under the influence of vibration and physical exertion, the most informative is the determination of the concentration of total testosterone, luteinizing hormone and insulin, the integral pituitary-adrenal index, and insulin resistance indices. To identify hidden disorders of the pituitary-thyroid system, the definition of the integral thyroid index can be used.

Optimization of diagnostic system of hand diseases in employees working under combined effects of vibration and physical overloads

The results of research carried out by theFederalScientificCenterfor Medical and Preventive Technologies of Public Health Risk Management Technologies for the period 2013–2018 showed that diseases associated with the combined effects of vibration and physical overload, employees of hazardous industries develop with experience of 15 years or more. The risk group is women older than 35 years and men older than 40 years. Pathology at the stage of detailed clinical manifestations is characterized by persistent pain syndrome, and, as a consequence, a decrease in the ability to work of workers.The aim of the study was to optimize the system of diagnosis of hand diseases in workers of industrial enterprises engaged in labor activities under the combined effects of vibration and physical overload, for the development of primary prevention programs.The observation group consisted of 32 employees aged 39.3±4.3 years, with an experience of 17.4±4.3 years; the comparison group consisted of 30 employees whose working conditions are not related to the studied factors; the average age was 40.6±3.4 years, experience was 19.1±3.1 years. The examination included analysis of the results of a special assessment of working conditions; assessment of neurological status; functional tests; laboratory studies (assessment of inflammation), hand dynamometry, stimulation electroneuromyography; x-rays of the hands and wrist joints, ultrasound examination of the hands.More than half of the surveyed persons of the observation group and 3/4 of the workers of the comparison group did not make complaints. Indicators of dynamometry of workers in both groups corresponded to physiological norm (p>0.05). Analysis of the results of dynamometer with data from previous years of PMO showed a decrease in strength of muscles of the hand leading hands on 2je,0–16. 7% and from 83.3% of the employees of the monitoring group and in 44.4% of the comparison group (p<0.05), in 50 % of the cases there was a decrease in the percentage of changes in the hand force variation (HFV) in the observation group, and in 38.9% of the cases the indicators remained unchanged. According to ultrasound of the hands, signs of tendinopathy were established in 85% of the employees of the observation group in the absence of persons with similar changes in the comparison group.In order to optimize the diagnosis of diseases of the hand in industrial workers who carry out their work under the combined effects of vibration and physical overload, in the case of a decrease in the rate of carpal dynamometry by 5% or more during the year, it is recommended to conduct ultrasound of the tendon-ligamentous apparatus of the hand, which will allow timely identification of early signs of tendinopathy.

THE STATE OF THE CENTRAL AND PERIPHERAL CONDUCTIVE STRUCTURES IN PATIENTS WITH VIBRATION DISEASE

Introduction. The defeat of motor and sensory conductive structures, which ultimately leads to the development of demyelination processes and, as a consequence, the formation of polyneuropathic syndrome is natural under the influence of industrial vibrations. Exposure to vibration, along with other harmful working conditions, can potentiate the development of metabolic syndrome, which can lead to the development of diabetes, which is one of the most common causes of damage to the peripheral nervous system. Based on the above, it seems relevant to give a comprehensive assessment of the state of peripheral nerves and afferent conductive structures in workers exposed in their professional activities combined effect of local and general vibration, and patients with vibration disease, burdened with diabetes. Material and methods. 114 people were examined in clinical conditions. The observed cases included 50 with vibration disease (WB) associated with exposure to local and General vibration (group 1), the second group - 29 people with WB, burdened with type 2 diabetes. The control group (group 3) consisted of 35 conditionally healthy men, representative age (52.0±6.4 years) without contact with harmful factors of production. Results. In patients of group 1, changes were observed in increasing the time of postsynaptic activation of the posterior horns of the spinal cord and activation of neurons of the somatosensory zone of the cerebral cortex. In patients of group 2, changes in the state of the central afferent pathways were more pronounced, shown in increasing the time of the excitation wave from the cervical thickening to the thalamic nuclei, as well as violations in the state of the conductive structures in the thalamic region. Analysis of the peripheral nerves in group 1 patients revealed changes in demyelinating lesions of the motor and sensory components of the tibial nerve and changes in the speed indices of the nerves of the upper extremities. The examined 2 groups had similar disorders, there was a statistically significant decrease in the speed of sensory axons of the lower extremities. conclusion. It was found that the combined effect of vibration and diabetes mellitus leads to aggravation of the demyelination processes of both sensory and motor axons of peripheral nerves in patients. There is a statistically significant decrease in the amplitude of the M-response on the lower extremities.

An occupational hazard of workers of wagon-repair production

Introduction. Professional groups of railway workers engaged in the repair of wagons are directly responsible for the safety of railway traffic. The analysis of literature testifies to insufficient attention of researchers to the hygienic problems associated with labor activity of workers of wagon-repair production.The aim of the study is to assess the occupational risk to the health of wagon repair workers, due to the impact on them of factors of the working environment and the labor process.Materials and methods. The study used comprehensive hygienic studies using the methodology of occupational risk to worker’s health.Results. The leading factors of the working environment (class of working conditions 3.2–3.4), which are exposed to workers depending on the specifics of the work performed. Identified professional groups with medium (significant) high (unbearable) and very high (intolerable) category of a priori occupational risk: in wagon meintenance workshop — 17 groups (94% of jobs), in a wagon assembly workshop — 11 groups (80% jobs), in wagon wheel workshop — 3 group (100% jobs). At the same time, according to the request for medical care, employees were diagnosed with isolated cases of occupational diseases.The levels of morbidity with temporary disability of employees of the main workshops are statistically significant (p<0.05) higher than those of the control group in 1.4–1.9 times. The influence of the complex of chemical factors of low and medium intensity on the levels of morbidity of respiratory diseases in the group of workers of the wagon wheel workshop, which were 1.7–2.0 times higher than in the control group, is confirmed by the average degree of causation of the production condition of this pathology (RR=1.7; EF=42.0%).The combined effect of vibration and severity of the labor process forms a high level of temporary disability of employees of the main workshops in connection with diseases of the musculoskeletal system, which was 2.7–4.4 times higher than in the control group, and also determines the prevalence of this pathology in the structure of diseases detected on medical examinations (23.2%). Diseases of the musculoskeletal system are caused by the production of employees of the wagon meintenance workshop (RR=3,9; EF=74,9%), as the most unfavorable in terms of hygiene on these factors.The stressful influence of the complex of harmful production factors on the health of wagon repair workers is manifested by the high risk of diseases of the cardiovascular system, gastrointestinal tract, neurological disorders, violation of adaptation of the cardiovascular system in 97% of the examined, as well as the predominance of diseases of the digestive system and circulatory system detected on periodic medical examinations.Conclusions. Harmful working conditions (class 3.1–3.4) cause the suspected occupational risk from small (moderate) to very high (intolerable) to 100% of the jobs of wagon repair workers. The results of the study of morbidity and risk of pathology indicate a significant risk of damage to the health of workers.

Effect of vibration during local anesthesia administration on pain, anxiety, and behavior of pediatric patients aged 6–11 years: A crossover split-mouth study

BackgroundUncooperative behavior of children due to dental anxiety may interfere with the effective delivery of dental care and compromise the quality of treatment provided. Injection of local anesthesia is one of the most anxiety-inducing stimuli in pediatric dentistry. This study aimed to compare the efficacy of a child-friendly device, having a combined effect of vibration and distraction, with the conventional method of injection on pain, anxiety, and behavior of pediatric patients aged 6–11 years.MethodsThis randomized, crossover, split-mouth study included 30 children requiring a bilateral inferior alveolar nerve block. The children were equally divided into two groups: group 1, aged 6–8 and group 2, aged 9–11 years. All children were injected with anesthesia using the conventional and device method in two separate sessions. They were assessed for anxiety by measuring the pulse rate before and during the administration of local anesthesia. Behavior was assessed using Faces, Legs, Activity, Cry, Consolability (FLACC) scale, and the child's experience while receiving anesthesia was assessed using the Wong Bakers Pain Rating Scale.ResultsResults showed that the children who received local anesthesia using the device method had a lower mean pulse rate, FLACC scores, and pain rating scores than those who received local anesthesia using the conventional method.ConclusionThe device method was more effective than the conventional method in managing pain, anxiety, and behavior of patients aged 6–11 years. The device is a cost effective, simple, and child-friendly product for administrating local anesthesia in pediatric patients.

Combined effect of whole-body vibration and ambient lighting on human discomfort, heart rate, and reaction time.

This study aimed to investigate the effect of whole-body vibration and ambient lighting, as well as their combined effect on human discomfort, heart rate, and reaction time in laboratory conditions. 44 men were recruited with an average age of 25.4 ± 1.9years. Each participant was subjected to 12 experimental steps, each step lasting five minutes for four different vibration accelerations in X, Y, and Z axes at a fixed frequency; three different lighting intensities of 50, 500, and 1000lx were also considered. At each step, a visual computerized reaction test was taken from subjects and their heart rate recorded by pulse oximeter. In addition, the discomfort rate of subjects was measured using Borg scale. Increasing vibration acceleration significantly increased the discomfort rate and heart beat but not the reaction time. Lack of lighting caused more discomfort in the subjects, but there was no significant correlation between lighting intensity with heart rate and reaction time. The results also showed that the combined effect of vibration and lighting had no significant effect on any of the discomfort, heart rate, and reaction time variables. Whole-body vibration is an important factor in the development of human subjective and physiological reactions compared to lighting. Therefore, consideration of the level of vibration to which an individual is exposed in workplaces subject to vibration plays an important role in reducing the level of human discomfort, but its interaction with ambient lighting does not have a significant effect on human subjective and physiological responses.

1E2-4 振動と音の複合作用に関する研究

1E2-4 振動と音の複合作用に関する研究

The role of whole body vibration, posture and manual materials handling as risk factors for low back pain in occupational drivers

It seems evident that occupational drivers have an increased risk of developing back pain. Not only are they exposed to whole body vibration (vibration), their work often includes exposure to several other risk factors for low back pain (LBP), particularly the seated posture (posture) and manual materials handling (MMH). Excessive demands on posture are likely to be aggravated by vibration and vice versa, and the risks may be further compounded when MMH is performed. This study investigated the relative role of vibration, posture and MMH as risk factors for LBP and the stated hypothesis was that the risks for LBP in drivers are the combined effect of vibration, posture and/or MMH. The findings showed that interaction effects due to posture and one or both of vibration and MMH, rather than the individual exposure effects, are the main contributors for precipitation of LBP.

Development and Utilization of Ride Comfort Simulator

A new ride comfort simulator has been developed to improve passenger comfort on trains. The test example features a 12-seat passenger cabin mockup mounted on an electrically powered 6-axis motion base. Since the simulator's vibration, noise and temperature levels as well as its landscape scenery visuals can be independently controlled, the simulator contributes data to identify the influence on passenger comfort of each factor or plural factors. In this paper, we outline the simulator's special features and introduce four experiments: the combined effects of vibration and sound on passenger comfort; optimal strap and handrail positions on commuter trains; optimal table dimensions for PC users on express trains; and the postural balance of passengers walking through a moving train.

Experimental studies on the effects of vibration and noise on sympathetic nerve activity in skin

Multi-unit sympathetic activity was recorded at elbow level from median nerve fascicles supplying glabrous skin of the left hand in five healthy subjects. The resultant vasomotor responses accompanying the neural activity were monitored by simultaneous recordings of skin blood flow using the laser doppler method and skin temperature in the innervation zones. No significant change in sympathetic activity was observed during handgrip exercise of the right hand under a constant gripping force of 2 kg. Subjects maintained the same gripping force of the right hand during exposure in random order to local vibration and/or noise, each type of exposure lasting 5 min with intervals of 20 min. A two-peaked significant increase in outflow from sympathetic nerves was observed during local exposure of the right hand to vibration with a frequency of 60 Hz and an acceleration of 50 m.s-2, followed by a postexposure period which revealed a relative suppression of sympathetic nerve activity and a significant increase in blood flow. Noise at 100 dB(A) showed only an initial effect on skin sympathetic nerve activity (SSA), whereas when combined with local vibration at 60 Hz, a pronounced increase in neural activity was noticed, indicating a combined effect of vibration and noise. These results from direct recordings of SSA suggest a sympathetic vasomotor reflex mechanism triggered by local vibration stimuli to the hand.

Combined effects of vibration and noise on palmar sweating in healthy subjects.

The combined effects of vibration and noise on palmar sweating were studied experimentally in healthy subjects. Ten subjects were exposed to vibration at an acceleration of 100 m.sec-2 root mean square at a frequency of 125 Hz, a noise level of 105 dB(A) at a frequency of 1000 Hz and both stimuli together. Vibration was applied to the right hand and noise to both ears from headphones. Palmar sweating was measured by the ventilated capsule method. Vibration caused a marked increase in palmar sweating of the right hand directly exposed to vibration and also of the left hand not exposed to vibration. Simultaneous vibration and noise caused a greater increase in palmar sweating than by each of the factors separately. The combined effects tended to be greater in subjects who were more susceptible to vibration or noise.

Combined effect of vibration and toxic chemicals : L. Ya. Tartakovskaya 1983 Gigiena Truda i Professional'nye Zabolevaniya27(3), 11–14. (4 pages, 14 references)

Combined effect of vibration and toxic chemicals : L. Ya. Tartakovskaya 1983 Gigiena Truda i Professional'nye Zabolevaniya27(3), 11–14. (4 pages, 14 references)

Some results of the effect of space flight factors on Drosophila melanogaster

Two experiments with Drosophila melanogaster males were performed aboard the Salyut 6 orbital station. Mutagenic effects of a 8 day space flight on sex chromosome nondisjunction and intergene recombination in chromosome II were studied. The space flight factors (SFF) increased the frequency of chromosome nondisjunction and recombination. The model experiments showed that the combined effects of vibration and acceleration do not cover the whole spectrum of space flight mutagenic factors. These data suggest that heavy space ions are mainly responsible for the observed effect.