ABSTRACT
RESUMO Este estudo teve como objetivo avaliar as características da pressão plantar, tipo e sensibilidade do pé em recrutas durante o período do serviço militar obrigatório. Sessenta indivíduos que prestaram o serviço militar obrigatório foram avaliados para pressão plantar (baropodômetro EPS LoranEngineering, Bolonha, Itália) e sensibilidade plantar ao toque superficial (estesiômetro de Semmes-Weinsten) em três momentos distintos: março (linha de base), junho (após 16 semanas de treinamento) e setembro (após 36 semanas de treinamento militar). Foram avaliadas a descarga de peso ântero-posterior e latero-lateral, pressão média, pressão máxima, área de contato do pé, tipologia de pé e sensibilidade plantar. Os dados foram analisados pelo teste do Qui-quadrado, anova de medidas repetidas e pelo teste de Friedman com pos hoc de Bonferroni (p<0,05). Houve aumento na área de contato (p=0,001) e na pressão média de ambos os pés (p<0,001). Quanto a tipologia, aproximadamente 60% dos indivíduos possuíam o pé direito do tipo normal, enquanto o pé esquerdo era do tipo cavo (50,3%); ou seja, mesmos sujeitos apresentaram diferentes tipologias do pé. Em relação a sensibilidade plantar, houve diferença na região do médio pé ao longo do treinamento (p=0,001 no pé dominante e p=0,009 no pé não dominante). Esses resultados demonstram que houve aumento da pressão média e área total de contato do pé, bem como alterações na sensibilidade plantar da região do médio pé ao longo do serviço militar obrigatório.
RESUMEN Este estudio tuvo como objetivo evaluar las características de la presión plantar, el tipo de pie y la sensibilidad en los reclutas durante el período de servicio militar obligatorio. Sesenta individuos que realizaron el servicio militar obligatorio fueron evaluados para presión plantar (baropodómetro EPS LoranEngineering, Bolonia, Italia) y sensibilidad plantar al tacto superficial (estesiómetro Semmes-Weinsten) en tres momentos diferentes: marzo (línea base), junio (después de 16 semanas de entrenamiento) y septiembre (después de 36 semanas de entrenamiento militar). Se evaluaron descarga de peso anteroposterior y laterolateral, presión media, presión máxima, área de contacto del pie, tipología del pie y sensibilidad plantar. Los datos se analizaron mediante el test de chi-cuadrado, el ANOVA de medidas repetidas y el test de Friedman con Bonferroni pos hoc (p <0,05). Hubo un aumento en el área de contacto (p=0,001) y en la presión media de ambos pies (p <0,001). En cuanto a la tipología, aproximadamente el 60% de los individuos tenían el pie dominante de tipo normal, mientras que el pie no dominante era de tipo cavo (50,3%); es decir, los mismos sujetos presentaron diferentes tipologías del pie. En cuanto a la sensibilidad plantar, hubo una diferencia en la región del mediopié durante el entrenamiento (p=0,001 en el pie dominante y p=0,009 en el pie no dominante). Estos resultados demuestran que hubo un aumento en la presión media y el área total de contacto del pie, así como cambios en la sensibilidad plantar en la región del mediopié durante el servicio militar obligatorio.
ABSTRACT This study aimed to evaluate the characteristics of plantar pressure, type of foot and plantar sensitivity of recruits during the period of compulsory military service. Sixty individuals who performed compulsory military service were assessed for plantar pressure (EPS LoranEngineering baropodometer, Bologna, Italy) and plantar sensitivity to superficial touch (esthesiometer - Semmes-Weinsten Monofilaments) at three different times: March (baseline), June (after 16 weeks of training) and September (after 36 weeks of military training). Antero-posterior and latero-lateral weight bearing, mean pressure, maximum pressure, foot contact area, foot typology were evaluated. and plantar sensitivity. The data were analyzed using the chi-squared test, Anova repeated measures and Friedman test with Bonferroni pos hoc (p<0,05). There was an increase in contact area (p=0,001) and mean pressure of both feet (p<0,001). As for the typology, an average of 60% of the individuals have the dominant foot of the normal type, while the non-dominant foot are cavus (50.3%), that is, the same subjects presented different typologies of the foot. Regarding plantar sensitivity, there was a difference in the midfoot region over training time (p=0.001 in the dominant foot and p=0.009 in the non-dominant foot). These results demonstrated that there was an increase in average pressure and total foot contact area, and also plantar sensitivity alterations throughout the mandatory military period.
ABSTRACT
Dentin hypersensitivity is an abrupt intense pain caused by innocuous stimuli to exposed dentinal tubules. Mechanosensitive ion channels have been assessed in dental primary afferent neurons and odontoblasts to explain dentin hypersensitivity. Dentinal fluid dynamics evoked by various stimuli to exposed dentin cause mechanical stress to the structures underlying dentin. This review briefly discusses three hypotheses regarding dentin hypersensitivity and introduces recent findings on mechanosensitive ion channels expressed in the dental sensory system and discusses how the activation of these ion channels is involved in dentin hypersensitivity.
Subject(s)
Dental Physiological Phenomena , Dentin Sensitivity , Dentin , Dentinal Fluid , Hydrodynamics , Ion Channels , Mechanoreceptors , Neurons, Afferent , Odontoblasts , Stress, MechanicalABSTRACT
Objective To investigate the changes of mechanoreceptors in the different state remnant stumps after anterior cruciate ligament(ACL)rupture.Methods From March 2013 to December 2015,fifty-seven cases of complete ACL rupture were collected to record the time interval from injury to surgery.The patients were divided into two groups according to preoperative kneelax joint measurement results:≤6 mm group (group 1)and>6 mm group(group 2).The morphology of each ligament stump in the two groups was recorded.After H&E staining and immunohistochemical labeling,the morphology,type,and quantity of the mechanoreceptors in the ligament stump were observed under an optical microscope.The relationship among the changes of the mechanoreceptors in the remnant stumps and the morphology of the ligament stump,the affected knee stability and the time from injury to surgery were analyzed.Results Twenty specimens were included in group 1.While 37 specimens were included in group 2.There was significant difference between the two groups in the distributions of the 4 types of the remnant stumps(P=0.000).There was significant difference between the two groups in the distributions of the 4 types of mechanoreceptors(P= 0.002).The number of the mechanoreceptors was positively correlated with the affected knee stability(r=0.63,P=0.018).There was no significant correlation between the number of the mechanoreceptors and the time from injury to surgery in group1 (r=-0.37,P=0.136),while the number of the mechanoreceptors was negatively correlated with the time from injury to surgery in group 2(r=-0.51,P =0.022).Conclusion After ACL rupture,the ligament stump in some patients still connect the femur and the tibia in the joint cavity,and exert mechanical stability function, which can retain the mechanoreceptors in the tissue for a long time.
ABSTRACT
OBJECTIVES: To map mechanoreceptor response in various regions of the laryngopharynx. METHODS: Five patients with suspected laryngopharyngeal reflux and six healthy control subjects underwent stimulation of mechanoreceptors in the hypopharynx, interarytenoid area, arytenoids, aryepiglottic folds, and pyriform sinuses. The threshold stimuli evoking sensation and eliciting laryngeal adductor reflex were recorded. RESULTS: In controls, an air pulse with 2 mmHg pressure evoked mechanoreceptor response in all regions, except bilateral aryepiglottic folds of one control. In patients, stimulus intensity to elicit mechanoreceptor response ranged between 2 mmHg and 10 mmHg and varied among the regions. Air pulse intensity differed between right and left sides of laryngopharyngeal regions in the majority of patients. CONCLUSION: Laryngopharyngeal mechanoreceptor response was uniform among regions and subjects in the healthy group. Patients with suspected laryngopharyngeal reflux showed inter- and intra-regional variations in mechanoreceptor response. Laryngopharyngeal sensory deficit in patients with suspected laryngopharyngeal reflux is not limited to aryepiglottic folds.
Subject(s)
Humans , Hypopharynx , Laryngopharyngeal Reflux , Mechanoreceptors , Pyriform Sinus , Reflex , SensationABSTRACT
Recently, rising curiosity on remnant preservation technique of anterior cruciate ligament (ACL) reconstruction, there is much interested in being and distribution of the mechanoreceptor of ACL. So, we performed histologic analyzing and mapping of sensory nerve fiber of the human ACL in this study. Total of 20 anterior cruciate ligaments were obtained from total knee replacement. Each ACL samples was divided into seven specimens; tibial insertion site, mid transitional site, femoral insertion site, and in between the sites, and total of 140 tissue samples were stained with hematoxylin-eosin and immunohistochemical, and observed with light microscope. Five hundred thirty-four fine neuroparticle structures, Ruffini corpuscles, and free nerve endings were observed in 20 ACL samples. The mean of fibers observed were 1.88, 1.71, 1.15, 1.08, 1.15, 1.55, and 1.82, respectively from tibial insertional site to femoral insertional site. With immunohistochemical stain, S-100 protein was strong positive at nerve cells, but was weak positive or negative at neurofilament. Mapping of sensory nerve distribution were done based on the results. We identified the mechanoreceptor of the human ACL using optical and immunohistochemical methods and mapped the histologic distribution of that.
Subject(s)
Humans , Anterior Cruciate Ligament , Arthroplasty, Replacement, Knee , Exploratory Behavior , Light , Mechanoreceptors , Nerve Endings , Nerve Fibers , Neurons , Proprioception , S100 ProteinsABSTRACT
Antennal sensilla of Anastrepha fraterculus (Wied.) were examined using scanning electron microscopy. In the flagellum, there are trichoid, basiconic, clavate type I and II, and styloconic sensilla and microtrichia. Only microtrichiae and chaetica sensilla were observed in the scape and pedicel. The number of sensilla in the flagellum was similar between sexes. At the apex there was a higher density of trichoid and an absence of clavate sensilla, while basiconic sensilla were more abundant in the proximal region.
Subject(s)
Animals , Arthropod Antennae/anatomy & histology , Sensilla/anatomy & histology , Tephritidae/anatomy & histology , Microscopy, Electron, ScanningABSTRACT
PURPOSE: This study was designed to determine the quantitative changes of the numbers of the mechanoreceptors in the experimentally tenotomized Achilles tendon of rabbits as compared with short-term immobilization and long-term immobilization. MATERIALS AND METHODS: 14 white rabbits were used. After tenotomizing the right Achilles tendon, the subjects were divided into 2 groups according to the periods of immobilizaton. The left side of each Achilles tendon of the rabbits were used as controls. The tendons were stained with a modified gold-chloride method. RESULTS: The number of mechanoreceptor was significantly decreased in the tenotomized Achilles tendon group than the control group (p0.01). CONCLUSION: The injured Achilles tendons may more vulnerable to injury because of the decreased numbers of mechanoreceptors, but no difference between the periods of immobilization. It may suggest that post-operative immobilization period may not affect on the outcome of operative treatment from the viewpoint of mechanoreceptors.
Subject(s)
Humans , Rabbits , Achilles Tendon , White People , Immobilization , Mechanoreceptors , TendonsABSTRACT
PURPOSE: This study was designed to determine the quantitative changes of the numbers of the mechanoreceptors in the experimentally tenotomized Achilles tendon of rabbits as compared with short-term immobilization and long-term immobilization. MATERIALS AND METHODS: 14 white rabbits were used. After tenotomizing the right Achilles tendon, the subjects were divided into 2 groups according to the periods of immobilizaton. The left side of each Achilles tendon of the rabbits were used as controls. The tendons were stained with a modified gold-chloride method. RESULTS: The number of mechanoreceptor was significantly decreased in the tenotomized Achilles tendon group than the control group (p0.01). CONCLUSION: The injured Achilles tendons may more vulnerable to injury because of the decreased numbers of mechanoreceptors, but no difference between the periods of immobilization. It may suggest that post-operative immobilization period may not affect on the outcome of operative treatment from the viewpoint of mechanoreceptors.
Subject(s)
Humans , Rabbits , Achilles Tendon , White People , Immobilization , Mechanoreceptors , TendonsABSTRACT
PURPOSE: To identify the change of mechanoreceptor of anterior cruciate ligament (ACL) in fixed knee and injured ACL. MATERIALS AND METHODS: Eighteen rabbits were divided into three groups as control, fixed knee, and injured ACL groups. Both knee of all fixed knee group were fixed with K-wire on the first day. The ligaments of the injured ACL group were cut at tibial attatchment site on the first day. Two rabbits of each group were sacrificed for the evaluation of mechanoreceptor at the 1st, 3rd, and 5th week. Histologic studies were performed by modified gold-chloride stain for the mechanoreceptors RESULTS: The types of mechanoreceptor in normal ACL were type I, type II, and type III. There was no difference in the appearance rate of each type. In the fixed knee group, the frequency of appearance decreased significantly at 5th week compared with that of the control group. In the injured ACL group, the frequency of appearance decreased at 1st week and showed no difference at 3rd week in comparison with 1st week, and zero at 5th week. In morphology the degree of degradation of mechanoreceptor increased with time in both experimental group, and showed more severe in the injured ACL group than in the fixed knee group. Most of all mechanoreceptors were located in the subsynovial region, and degraded with synovial degeneration and synovial inflammation. CONCLUSION: Mechanoreceptors were changed with the change of intra-articular condition and ligament itself. Therefore the duration of immobilization shoud be shortened if possible and the torn ACL should be repaired anatomically, if indicated, as soon as possible to preserve the mechanoreceptors.
Subject(s)
Rabbits , Anterior Cruciate Ligament , Immobilization , Inflammation , Knee , Ligaments , MechanoreceptorsABSTRACT
PURPOSE: The purposes of this study was to evaluate the changes in the mechanoreceptor in the anterior cruciate ligament(ACL) in relation to the healing course following transected posterior cruciate ligament(PCL) MATERIAL AND METHODS: Adult New Zealand White rabbits were used in our study. The PCLs of 40 rabbits were transected at mid-substance on one side. Sham operation was performed on the contralateral side, which served as their own control. At postoperative 2nd, 12th, 24th and 36th week, subsequent changes of the mechanoreceptors were examed histologically with modified gold-chloride staining and arthritic change of cartilage was examed by gross inspection. RESULTS: On gross inspection, the healing process of the transected PCLs began to appear at 6th week, since then the width has steadily increased. There was no evidence of cartilage degeneration from 6th week to 36th week. The number of mechanoreceptor was statistically decreased and morphological degradation was seen as compared with the control side at 6th, 12th and 24th week. The number of type 2 and type 3 mechanoreceptor had been statistically increased over time as the healing of PCL progressed. CONCLUSION: In rabbit model, the mechanoreceptor in ACL changed in response to the stability of the knee with injured PCL. But, further studies are necessary to explain the correlation between the change of mechanoreceptor in ACL and development of arthritis in the knee with injured PCL
Subject(s)
Adult , Humans , Rabbits , Anterior Cruciate Ligament , Arthritis , Cartilage , Knee , Mechanoreceptors , Posterior Cruciate LigamentABSTRACT
BACKGROUND: Recent findings suggest that a coupling between the somatic and sympathetic nervous system is critical not only for the development but also for the maintenance of pain behavioral changes. However, studies on the effect of sympathetic efferent system on sensory receptors in the visceral organ that is more dependent on the autonomic nervous system are lacking. This study examined whether norepinephrine (NE) had an influence on the mechanoreceptors in the feline urinary bladder. METHODS: Ten adult male cats were used and anesthetized with alpha-chloralose and artificially ventilated. A cannula with the pressure transducer was inserted through the urethra to apply mechanical stimuli and monitor the pressure of bladder. A tiny cannula inserted into the bilateral side branches of vesical arteries were used as a route for a NE (10A.M 9:40 01-10-08 bilaterally) injection. Nerve fiber recordings were obtained from the distal stump of the pelvic nerve. RESULTS: After the NE injection, the response of mechanoreceptors (n = 13) to the isotonic pressure stimulus (50 - 60 mmHg) decreased significantly (p < 0.05) in terms of sensitivity (i.e., ratio of nerve activity change to urinary bladder pressure change). The responses to pressure stimuli after an injection of an alpha1 adrenoceptor blocker (terazosin) reversed the effect of NE. The responses of mechanoreceptors to isotonic pressure stimulus were not affected significantly by NE with preinjection of an alpha2 adrenoceptor blocker (yohimbine). CONCLUSIONS: These results suggest that NE may have influence on the sensitivity of mechanoreceptors in the normal feline urinary bladder via an alpha1 adrenoceptor.
Subject(s)
Adult , Animals , Cats , Humans , Male , Adrenergic alpha-1 Receptor Antagonists , Arteries , Autonomic Nervous System , Catheters , Chloralose , Mechanoreceptors , Nerve Fibers , Norepinephrine , Sensory Receptor Cells , Sympathetic Nervous System , Transducers, Pressure , Urethra , Urinary BladderABSTRACT
PURPOSE: This study aimed to observe the effect of femoral lengthening on proprioceptive nerve endings of the anterior cruciate ligament in rabbits and to evaluate the relationship between changes in the number of mechanoreceptors and electrophysiologic abnormalities, and histomorphological changes in the ligament, according to the length gain. MATERIAL AND METHODS: Forty rabbits were divided into two groups, such as 10% and 20% lengthening. Each ipsilateral femur was distracted by gradual method and the contralateral side was used for the sham group. Distraction at a rate of 1 mm per day was started on the 5th day postoperatively. The frequency of distraction was 2 steps per day. At the end of the experiment, nerve conduction studies including amplitude, latency and area of compound muscle action potential (CMAP) were measured. Modified gold-chloride stain was used for detection of proprioceptive nerve endings of the anterior cruciate ligament and hematoxylin-eosin stain was used for light microscopic examinations of the anterior cruciate ligament. Among 40 animals, 7 were excluded in our study due to experimental faults which were 3 inadequate osteotomy, 2 premature consolidation and 2 sepsis. Three types of mechanoreceptors were identified by Freeman and Wyke criteria. RESULT: There was a statistically significant reduced number of three morphological kinds of corpuscles in anterior cruciate ligaments in the 20% lengthening group than in the sham group (p<0.03) . Morphological changes of synovium on the anterior cruciate ligaments were more evident in the lengthened groups rather than in the ligament itself. However, there was little relationship between abnormalities of nerve conduction velocity and the change in number of proprioceptive nerve endings. CONCLUSION: This study provided morphological evidence of the harmful effects on proprioceptive function of adjacent joints due to lengthening, and that femoral lengthening may alter the neurophysiological function of the knee joint by decreasing the number of mechanoreceptors in the anterior cruciate ligament. As well, this morphological change by limb lengthening did not seem to be related to distraction neuropathy.
Subject(s)
Animals , Rabbits , Action Potentials , Anterior Cruciate Ligament , Extremities , Femur , Joints , Knee Joint , Ligaments , Mechanoreceptors , Nerve Endings , Neural Conduction , Osteotomy , Sepsis , Synovial MembraneABSTRACT
The aim of this study was to determine whether there are quantitative changes in the mechanoreceptors in the anterior cruciate ligament of unstable knee with injured medial articular cartilage or medial ligament. Twenty specimens of anterior cruciate ligament were obtained from medial articular cartilage injury group and medial ligament injury group, respectively. Forty anterior cruciate ligaments of the other side of knee were used as controls. The ligaments were transected and stained with a modified gold-chloride method. Mechanoreceptors were located almost exclusively in the periligamentous synovial tissue. The results were as follows; 1. Three kinds of mechanoreceptors were found at the surface of each ligament beneath the synovial membrane. 2. The type 2 mechanoreceptor was more common than any other types in all groups. 3. In the medial articular cartilage injury group, the number of mechanoreceptor was significantly decreased and morphologically degradated with synovial degeneration than the control group. The same findings were noted in the medial ligament injury group(P<0.003). 4. There was no statistical difference between the two experimental groups in numher of the mechanoreceptor. In conclusion, the mechanoreceptor of the anterior cruciate ligament of unstable knee with injured medial articular cartilage and ligament in the rabbit were decreased in its numher and were degradated morphologically than the control group. And it was suggested that reduced proprioception in unstable knee might he an another cause of development of osteoarthritis.