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This study aimed to investigate the radiation absorption effects of the humeral locking plate system on breast tissue in different radiological energy ranges using MCNPX (Monte Carlo N-Particle Extended Transport Code System, version 2.6.0) general-purpose Monte Carlo code. In the present study, a novel MCNPX simulation setup has been generated considering the elemental mass fractions of investigated materials and biological structures. The validation of MCNPX simulation geometry used in this study has been provided by comparing the results with standard XCOM data for mass attenuation coefficients of Ti-6Al-4V alloy. A very good match between XCOM and MCNPX data has been achieved. Therefore, validated simulation input has been employed for further investigations of the present study. Our findings showed that the amount of absorbed energy that was measured in breast tissue with the humeral locking plate was higher than that without humeral locking plate for the same radiological energy value. Our results would be beneficial to use the present simulation technique and mass attenuation coefficients for radiation physics and medical applications, especially for assessments of breast cancer risk. [ABSTRACT FROM AUTHOR]

Copyright of Turkish Journal of Rheumatology is the property of Turkish League Against Rheumatism / Turkiye Romatizma Arastirma ve Savas Dernegi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The study was conducted to investigate the effects of mannanoligosaccharide (MOS) and probiotic supplementation on haematological and immunological parameters in turkeys. A total of 72, 15-day-old white hybrid converter turkey poults were used in this study. Poults were assigned into three groups, each group consisted of six poults and the trial was repeated four times. The control group was fed a basal diet without supplemented probiotic and MOS, and treatment groups were fed either 1 g/kg MOS or probiotic added diets. At the end of the 15-week treatment period, samples of blood were collected to determine immunological and haematological values. The comparison among the groups showed that both the probiotic and MOS supplementation resulted in significant increases ( P < 0.05) in the serum IgG and IgM levels, and significant decreases ( P < 0.05) in the peripheral blood T lymphocyte percentage compared with those of the control group. Mean serum IgG level (7.06 g/l) was significantly higher ( P < 0.05) in poults supplemented with probiotic compared with MOS (6.76 g/l). It was observed that the probiotic supplementation caused statistically significant increases ( P < 0.05) in the erythrocyte count, haemoglobin concentration and haematocrit values, but MOS supplementation did not have a significant effect ( P > 0.05) on these parameters. Total leucocyte and differential leucocyte counts were not affected by dietary MOS and probiotic supplementation. These results show that MOS or probiotic may elevate IgG and IgM levels in turkey. The MOS and probiotic that enhance immunoglobulin levels will have a more positive effect on growth performance, production and turkeys’ ability to resist disease. [ABSTRACT FROM AUTHOR]

Although there are many reports regarding the spinal surgical applications before the 19th century, the definition of spinal disorders and application of the most novel surgical techniques have been performed in last 2 centuries. Lumbar spinal stenosis was reported in the first half of the 20th century. The definition of the lumbar spinal stenosis was commonly attributed to Dr. Verbiest. However, there were some reports regarding the symptoms attributable to lumbar spinal stenosis before him. On the other hand, Dr. Sarpyener, a Turkish surgeon, reported for the first time congenital spinal stenosis, a special variety of spinal stenosis. The aim of this study is to review the biography, scientific studies, and spine applications of Dr. Sarpyener, a pioneer in the field of spina bifida and congenital spinal stenosis. [ABSTRACT FROM AUTHOR]

Objectives: The posterolateral sulcus (PLS) of the spinal cord is an important land mark for the dorsal root entry zone (DREZ) operation and for the removal of the laterally located spinal intramedullary tumors. In order to achieve a successful surgery, detailed knowledge of the anatomy and the variation of the region is necessary. Methods: Five formalin embalmed adult human cadavers (1 female and 4 males) were used. The number of posterior rootlets in each spinal level were identified and documented. The dorsal roots were examined under 10X microscope magnification. Transverse paraffin sections (10 Im) were cut and mounted on slides. To visualize white and the gray mater of the spinal cord slides were stained with luxol fast blue. The PLS and the dorsal horns were defined and measurements were made at X4, magnification, and photographed using a Nikon camera. Results: Histological examinations of the PLS showed a single layer of pia which extended between the dorsal and the lateral columns. Any separations between the dorsal and the lateral columns that did not contain pia were not evaluated as sulcus. There was no arachnoid covering within the sulcus. The number of dorsal rootlets at cervical levels ranged between 2-10 and the mean number was 7.6±1.4. The number of dorsal rootlets at thoracic level ranged between 3-9 and the mean number was 6.5±0.7. The number of dorsal rootlets at lumbar level ranged between 4-8 and the mean number was 6.1±0.4. The location of the extension of the pia into the PLS showed variations. Length and width measurements of the dorsal horn showed that the average width was largest at lower cervical and least at lower thoracic, whereas the average length was largest at upper thoracic and smallest at lower lumbar. Conclusion: Being aware of the variations of the PLS and the average number of rootlets at each spinal level can increase the success of regional surgery. [ABSTRACT FROM AUTHOR]

To evaluate the effect of 4 different levels of propolis supplementation on the hematological and immunological parameters of laying hens, a trial was conducted with 60 White Leghorn layer hens. The experiment was conducted by using a randomized design with 5 treatments, 4 replicates, and 3 hens in each replicate. Treatments included basal diet (control) and basal diet plus 0.5, 1, 3, and 6 g of propolis/kg of diet, respectively. At the end of the 12-wk treatment period, samples of blood were collected to determine hematological arid immunological values. The results showed that the addition of propolis at 3 g/kg in the diet resulted in significant increases (P < 0.05) in the serum IgG and IgM levels and significant decreases (P < 0.05) in the peripheral blood T-lymphocyte percentage compared with those of the control and other treatment groups. In addition, the level of 3 g/kg of propolis Supplementation significantly increased (P < 0.05) erytlirocyte count (red blood cells) compared with the other treatments. On the other hand, hemoglobin arid hematocrit values and total leucocyte (white blood cells) and differential leucocytes counts were not influenced by propolis supplementation. These results indicate that the inclusion of propolis at the level of 3 g/kg of diet may have a positive effect on humoral immunity of laying hens. [ABSTRACT FROM AUTHOR]

This study assesses human identification of vibrotactile patterns by using real-time discrete event-driven feedback. Previously acquired force and bend sensor data from a robotic hand were used to predict movement-type (stationary, flexion, contact, extension, release) and object-type (no object, hard object, soft object) states by using decision tree (DT) algorithms implemented in a field-programmable gate array (FPGA). Six able-bodied humans performed a 2- and 3-step sequential pattern recognition task in which state transitions were signaled as vibrotactile feedback. The stimuli were generated according to predicted classes represented by two frequencies (F1: 80 Hz, F2: 180 Hz) and two magnitudes (M1: low, M2: high) calibrated psychophysically for each participant; and they were applied by two actuators (Haptuators) placed on upper arms. A soft/hard object was mapped to F1/F2; and manipulating it with low/high force was assigned to M1/M2 in the left actuator. On the other hand, flexion/extension movement was mapped to F1/F2 in the right actuator, with movement in air as M1 and during object manipulation as M2. DT algorithm performed better for the object-type (97%) than the movement-type (88%) classification in real time. Participants could recognize feedback associated with 14 discrete-event sequences with low-to-medium accuracy. The performance was higher (76 ± 9% recall, 76 ± 17% precision, 78 ± 4% accuracy) for recognizing any one event in the sequences. The results show that FPGA implementation of classification for discrete event-driven vibrotactile feedback can be feasible in haptic devices with additional cues in the physical context.

Aim of the Study: Brain-computer interfaces (BCIs) may help patients with severe neurological deficits communicate with the external world. Based on microelectrocorticography (µECoG) data recorded from the primary somatosensory cortex (S1) of unrestrained behaving rats, this study attempts to decode lever presses in a psychophysical detection task by using machine learning algorithms., Materials and Methods: 16-channel Pt-Ir microelectrode arrays were implanted on the S1 of two rats, and µECoG was recorded during a vibrotactile yes/no detection task. For this task, the rats were trained to press the right lever when they detected the vibrotactile stimulus and the left lever when they did not. The multichannel µECoG data was analysed offline by time-frequency methods and its features were used for binary classification of the lever press at each trial. Several machine learning algorithms were tested as such., Results: The psychophysical sensitivities (A') were similar and low for both rats (0.58). Rat 2 ( B '': -0.11) had higher bias for the right lever than Rat 1 ( B '': - 0.01). The lever presses could be predicted with accuracies over 66% with all the tested algorithms, and the highest average accuracy (78%) was with the support vector machine., Conclusion: According to the recent studies, sensory feedback increases the benefit of the BCIs. The current proof-of-concept study shows that lever presses can be decoded from the S1; therefore, this area may be utilised for a bidirectional BCI in the future.

Purpose: No study has addressed the effect of patient-reported outcomes as a visual feedback tool during telerehabilitation. This study aimed to investigate the effect of a visual feedback-based monitoring application PhysioAnalyst on pain, pain catastrophizing, physical functions, quality of life, usability, satisfaction, and exercise adherence in individuals with chronic low back pain (CLBP)., Methods: A single-blind, randomized controlled trial was conducted with 44 CLBP patients. Participants were randomized into two groups: the tele-assessment feedback group (TAFG) (n = 22) and the control group (CG) (n = 22). Participants were assessed before the intervention, at the 4th week and after the intervention. Individuals were assessed using the Visual Analog Scale (VAS), Nottingham Health Profile (NHP), Pain Catastrophizing Scale (PCS), Oswestry Disability Index (ODI), Telehealth Usability Questionnaire (TUQ), Telemedicine Satisfaction Questionnaire (TSQ), and Exercise Adaptation Rating Scale (EARS) via PhysioAnalyst. Individuals in the TAFG group received graph-based visual feedback on assessment data in week 4., Results: The improvement in VAS, NHP, ODI, TUQ, TSQ, and EARS of individuals in TAFG was statistically significant (p < 0.05). Only ODI and PCS scores in CG showed significant improvement (p < 0.05). After the graphics-based visual feedback presented to the TAFG, the VAS, NHP-Emotional, NHP-Sleep, NHP-Total, PCS, TUQ, TSQ, ODI, and EARS scores gained more than CG (p < 0.05)., Conclusion: The results confirmed the additional contribution of telerehabilitation's graphics-based visual feedback in pain, pain catastrophizing, disability, quality of life, and exercise participation. Since the importance of continuity in long-term rehabilitation in patients with CLBP is comprehended, feedback to increase patient motivation can be added to telerehabilitation applications., (© 2024. The Author(s).)

Introduction: Carpal tunnel syndrome (CTS) is the most common nerve entrapment neuropathy, which causes numbness and pain in the thumb, the index and middle fingers and the radial side of the ring finger. Regular hand exercises may improve the symptoms and prevent carpal tunnel surgery. This study applied a novel ultrasonic stimulation method to test tactile sensitivity in CTS and also a mixed-reality-assisted (MR-assisted) exercise program which measured hand movements and provided haptic feedback for rehabilitation., Methods: Twenty patients with mild unilateral CTS took part in the experiments. A mid-air haptics device (Ultrahaptics STRATOS Explore) was used to apply amplitude-modulated ultrasound waves (carrier frequency: 40 kHz) onto the skin to create tactile stimulation mechanically. Participants performed a two-alternative forced-choice task for measuring tactile thresholds at 250-Hz modulation frequency. They were tested at the index fingers and the thenar eminences of both hands. Additionally, 15 CTS patients used an MR-assisted program to do hand exercises with haptic feedback. Exercise performance was assessed by calculating errors between target and actual hand configurations. System Usability Scale (SUS) was adopted to verify the practical usability of the program., Results: Thresholds at the thenar eminences of the affected and healthy hands were not significantly different. While the thresholds at the healthy index fingers could be measured, those of the affected fingers were all higher than the stimulation level produced by the maximum output from the ultrasound device. In the exercise program, a significant positive correlation (ρ = 0.89, p  < 0.001) was found between the performance scores and the SUS scores, which were above the criterion value established in the literature., Discussion: The results show that thenar tactile sensitivity is not affected in mild CTS as expected from the palmar cutaneous branch of the median nerve (PCBm), but index finger threshold is likely to be higher. Overall, this study suggests that mid-air haptics, with certain improvements, may be used as a preliminary test in the clinical setting. Moreover, the device is promising to develop gamified rehabilitation programs and for the treatment follow-up of CTS., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2024 Akdağ, Menekşeoğlu, Seğmen, Gözek, Korkmaz and Güçlü.)

Purpose/aim of the Study: Few studies have demonstrated the effects of smartphone use on grip strength and upper extremity function. The present study was purposed to compare smartphone users' grip/lateral pinch strength, pain threshold/tolerance and upper limb function., Materials and Methods: A prospective cross-sectional study was conducted with 241 individuals. Participants were divided into three groups with the cut-off values of the Smartphone Addiction Scale (SAS). The Edinburgh Handedness Inventory (EHI) was used to determine the dominant side. Thumb pain threshold and tolerance were evaluated with the algometer. A hand dynamometer measured the grip and lateral pinch strength. Upper extremity functions were evaluated with the Shortened Disabilities of the Arm, Shoulder and Hand Questionnaire (Quick-DASH)., Results: Handgrip strength of the dominant/non-dominant extremities and Quick-DASH scores were higher in low-level smartphone users ( p  < 0.05). There was no significant difference between the groups on lateral pinch strength and pain threshold/tolerance ( p  > 0.05). Smartphone usage significantly affected dominant and non-dominant hand grip strength (Standardized β 1 = -0.15, β 2 = -0.15, p  < 0.05). In addition, the smartphone use level negatively affected dominant lateral pinch strength (Standardized β = -0.12, p  = 0.05). On the other hand, smartphone use positively affected upper extremity function (Standardized β  = 0.17, p  < 0.05)., Conclusions: As smartphone addiction increases, standard handgrip strength and functionality decrease. Pain threshold/tolerance is not affected by smartphone use. Future studies should focus on fine motor skills to present a more comprehensive upper limb function evaluation.

Decoding of sensorimotor information is essential for brain-computer interfaces (BCIs) as well as in normal functioning organisms. In this study, Bayesian models were developed for the prediction of binary decisions of 10 awake freely-moving male/female rats based on neural activity in a vibrotactile yes/no detection task. The vibrotactile stimuli were 40-Hz sinusoidal displacements (amplitude: 200 µm, duration: 0.5 s) applied on the glabrous skin. The task was to depress the right lever for stimulus detection and left lever for stimulus-off condition. Spike activity was recorded from 16-channel microwire arrays implanted in the hindlimb representation of primary somatosensory cortex (S1), overlapping also with the associated representation in the primary motor cortex (M1). Single-/multi-unit average spike rate (R d ) within the stimulus analysis window was used as the predictor of the stimulus state and the behavioral response at each trial based on a Bayesian network model. Due to high neural and psychophysical response variability for each rat and also across subjects, mean R d was not correlated with hit and false alarm rates. Despite the fluctuations in the neural data, the Bayesian model for each rat generated moderately good accuracy (0.60-0.90) and good class prediction scores (recall, precision, F1) and was also tested with subsets of data (e.g. regular vs. fast spike groups). It was generally observed that the models were better for rats with lower psychophysical performance (lower sensitivity index A'). This suggests that Bayesian inference and similar machine learning techniques may be especially helpful during the training phase of BCIs or for rehabilitation with neuroprostheses., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: The present study was aimed to compare the grip/pinch strengths and manual dexterity of individuals with and without the use of cannabis and its derivatives., Methods: A cross-sectional prospective study was conducted with 66 individuals, including 33 cases with the use of cannabis (and its derivatives) and 33 age- and sex-matched controls. Grip and pinch strengths were evaluated with a dynamometer. The Nine-Hole Peg Test (9HPT), Minnesota Manual Dexterity Test (MMDT), and Michigan Hand Outcomes Questionnaire (MHQ) were used to assess the hand function., Results: The hand grip strength and dominant hand 2-point pinch (2PP) grip strength were less in individuals with substance use disorder (SUD) (p < 0.05). The 9HPT duration of the SUD patients was higher (p < 0.05). On the other hand, the MMDT insertion and rotation test results were different between the groups (p < 0.05). Grip strength was related with the MMDT insertion and rotation tests (r =  -0.411 to -0.480). There was significant correlation between grip strength with dominant hand 9HPT (r =  -0.370) and between dominant hand 3-point pinch (3PP) strength with MMDT insertion (r =  -0.378). In addition, dominant hand 2PP strength was correlated with overall hand function of MHQ (r = 0.382)., Conclusion: The individuals with cannabis use disorder showed reduced grip strength on both sides and decreased 2PP strength on the dominant side compared to healthy individuals. In addition, there is a decrease in the hand skills of individuals with cannabis use disorder. Decreased grip strength of individuals with cannabis use disorder affected their hand skills negatively., (© 2022. The Author(s), under exclusive licence to Royal Academy of Medicine in Ireland.)

Objective:   The Pain Catastrophic Scale (PCS) is generally associated with high and low post-recovery satisfaction and measures the pain perception of patients in the literature. This study aims to evaluate the association of deliberate (as in a fight or anger causing punching a wall) boxer's fractures with catastrophic pain compared to accidental (as in a fall, accidental knocking it against a wall, etc.) fractures and evaluate the effect of anxiety about fracture union and functional recovery on clinical outcomes., Materials and Methods:  A total of 62 male patients with metacarpal fractures, 31 as a result of deliberate punching (1st group) and 31 with metacarpal fractures as a result of an accident (2nd group), who applied to the emergency department or orthopedic clinic with the diagnosis of metacarpal fracture between January 2021 and October 2022, were included in the study. All patients were selected from patients who were followed up with conservative plaster/splint. The PCS scores of the patients were evaluated comparatively with the clinical results measured after at least six weeks., Results:   The mean age of the patients was 30.8 (18-50) in the 1st group and 34.8 (18-64) in the 2nd Group, and no statistically significant difference was found (p=0.274). While the median PCS score was 10.5 (interquartile range {IQR}: 12.3) for the 1st group, the median PCS score was 17.5 (IQR: 14.5) for the 2nd group, and the PCS score was statistically significantly lower in group 1 (p=0.009). While the median Visual Analogue Scale (VAS) value was 0 (IQR: 0.3) for the 1st group, the median VAS value was 1 (IQR: 2.0) for the 2nd group, and the VAS score was statistically significantly lower in the 1st group (p<0.001). While the median 'quick disabilities of the arm, shoulder, and hand' (Q-DASH) value was 0 (IQR:2.3) for the 1st group, the median Q-DASH value was 3.4 (IQR:6.3) for the 2nd group, and the Q-DASH score was statistically significantly lower in the 1st group (p=0.001). No significant difference was observed between the 1st and 2nd groups in terms of grip strength values (p=0.815)., Conclusion: The etiology of patients presenting with a boxer's fracture should be well understood, and if necessary, these patients should be treated multidisciplinary, with psychiatric help. Better satisfaction can be achieved with lower results in patients whose PCS scoring system has lost its eigenvalue., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Bozduman et al.)

The mechanical impedance of intact and epidermis-peeled rat glabrous skin was studied at two sites (digit and sole) and at two frequencies (40 Hz and 250 Hz). The thicknesses of skin layers at the corresponding regions were measured histologically from intact- and peeled-skin samples in every subject. Compared to intact sole skin, digital rat skin has thicker layers and higher mechanical resistance, and it is less stiff. The resistance of the skin significantly decreased after epidermal peeling at both the digit and the sole. Furthermore, peeling caused the reactance to become positive due to inertial effects. As the frequency was increased from 40 to 250 Hz, the resistance and stiffness also increased for the intact skin, while the peeled skin showed less frictional (i.e., resistance) but more inertial (i.e., positive reactance) effects. We estimated the mechanical properties of epidermis and dermis with lumped-element models developed for both intact and peeled conditions. The models predicted that dermis has higher mass, lower stiffness, and lower resistance compared to epidermis, similar to the experimental impedance results obtained in the peeled condition which consisted mostly of dermis. The overall impedance was simulated more successfully at 40 Hz. When both frequencies are considered, the models produced consistent results for resistance in both conditions. The results imply that most of the model parameters should be frequency-dependent and suggest that mechanical properties of epidermis can be related to its thickness. These findings may help in designing artificial skin for neuroprosthetic limbs., (Copyright © 2022 by ASME.)

Purpose/aim of the study: We aimed to establish psychophysical principles for non-invasive vibrotactile feedback signalling discrete transition events (e.g., extension to flexion) during use of prostheses, especially for the upper limbs. Materials and methods: Two vibrotactile actuators were used on both upper arms of 10 able-bodied human participants. Absolute thresholds, psychometric functions, and magnitude estimates were measured to equalize the sensation magnitudes for the tested vibrotactile frequencies and skin sites. Then, same-different and pattern recognition tasks were run to evaluate, respectfully, the discrimination and closed-set identification of stimuli with varying parameters (2 frequencies, 2 magnitudes, 2 sites). Finally, parameters of the left/right stimuli were mapped to hypothetical prosthesis events representing object/force and movement type. The stimuli were applied sequentially in accordance with the discrete event-driven feedback paradigm. Results: Reliable psychophysical models could be established for individual participants as verified by repetitive threshold measurements and relative adjustment of stimulus levels based on sensation magnitudes. Discrimination accuracy was higher for magnitude versus frequency comparisons; and magnitude discrimination accuracy was correlated with magnitude estimate differences. Pattern recognition recall/precision rates decreased from ∼0.7 to ∼0.5 for sequential delivery of two stimulus patterns to one arm versus to two arms. Using the patterns as two and three consecutive prosthesis events yielded statistically similar performance rates not correlated with magnitude estimate differences. Conclusions: By careful calibration of stimuli based on psychophysical principles, discrete event-driven vibrotactile feedback can be used to signal manipulated object and movement information with moderate identification rates as shown by confusion matrices.

We present a stochastic learning model that combines the essential elements of Hebbian and Rescorla-Wagner theories for operant conditioning. The model was used to predict the behavioral data of rats performing a vibrotactile yes/no detection task. Probabilistic nature of learning was implemented by trial-by-trial variability in the random distributions of associative strengths between the sensory and the response representations. By using measures derived from log-likelihoods (corrected Akaike and Bayesian information criteria), the proposed model and its subtypes were compared with each other, and with previous models in the literature, including reinforcement learning model with softmax rule and drift diffusion model. The main difference between these models was the level of stochasticity which was implemented as associative variation or response selection. The proposed model with subject-dependent variance coefficient (SVC) and with trial-dependent variance coefficient (TVC) resulted in better trial-by-trial fits to experimental data than the other tested models based on information criteria. Additionally, surrogate data were simulated with estimated parameters and the performance of the models were compared based on psychophysical measures (A': non-parametric sensitivity index, hits and false alarms on receiver operating characteristics). Especially the TVC model could produce psychophysical measures closer to those of the experimental data than the alternative models. The presented approach is novel for linking psychophysical response measures with learning in a yes/no detection task, and may be used in neural engineering applications.

Basal forebrain (BF) cholinergic system is important for attention and modulates sensory processing. We focused on the hindpaw representation in rat primary somatosensory cortex (S1), which receives inputs related to mechanoreceptors identical to those in human glabrous skin. Spike data were recorded from S1 tactile neurons (n = 87) with (ON condition: 0.5-ms bipolar current pulses at 100 Hz; amplitude 50 μA, duration 0.5 s at each trial) and without (OFF condition) electrical stimulation of BF in anesthetized rats. We expected that prior activation of BF would induce changes in the vibrotactile responses of neurons during sinusoidal (5, 40, and 250 Hz) mechanical stimulation of the glabrous skin. The experiment consisted of sequential OFF-ON conditions in two-time blocks separated by 30 min to test possible remaining effects. Average firing rates (AFRs) and vector strengths of spike phases (VS) were analyzed for different neuron types [regular spiking (RS) and fast spiking (FS)] in different cortical layers (III-VI). Immediate effect of BF activation was only significant by increasing synchronization to 5-Hz vibrotactile stimulus within the second block. Regardless of frequency, ON-OFF paired VS differences were significantly higher in the second block compared to the first, more prominent for RS neurons, and in general for neurons in layers III and VI. No such effects could be found on AFRs. The results suggest that cholinergic activation induces some changes in the hindpaw area, enabling relatively higher increases in synchronization to vibrotactile inputs with subsequent BF modulation. In addition, this modulation depends on neuron type and layer, which may be related to detailed projection pattern from BF.

Non-NMDA receptor-mediated vibrotactile responses of neurons from the hindpaw representation were investigated in the rat SI cortex. We recorded single-unit spikes evoked by sinusoidal (duration: 500 ms; frequency: 5, 40, and 250 Hz; amplitude: 100 μm peak-to-peak) stimulation of the glabrous skin. The responses were obtained with microinjection of aCSF (sham), bicuculline, and AMPA near the isolated neurons in anaesthetized rats. Blocking most of the NMDA receptors by ketamine revealed local dynamics differentially modulated by each drug. The responses were generally suppressed after the initial 100-ms period of the 40- and 250-Hz stimulus, but not at 5 Hz. Both drugs increased average firing rates (AFRs) only during vibrotactile stimulation, and increased entrainment as measured by the vector strength (VS) of spike phases. However, bicuculline was more effective on the AFR in the late period particularly at 40 Hz. Complex interactions were found with AMPA; late activity increased only for fast spiking neurons at 40 Hz, and more for regular spiking neurons at 5 Hz. The increase of VS by bicuculline was much higher in layer IV. In addition to thalamocortical feed-forward inhibition, vibrotactile information seems to be suppressed after 100 ms by longer-latency inhibitory networks tuned to mid-frequency inputs. Combined with the presumed AMPA-receptor desensitization, those two inhibitory factors could limit the excitatory flow mostly to lower frequencies. The frequency dependence of the drug effects highlights the role of local cortical dynamics in the hindpaw area.

The Pacinian corpuscle (PC) is a cutaneous mechanoreceptor that senses low-amplitude, high-frequency vibrations. The PC contains a nerve fiber surrounded by alternating layers of solid lamellae and interlamellar fluid, and this structure is hypothesized to contribute to the PC's role as a band-pass filter for vibrations. In this study, we sought to evaluate the relationship between the PC's material and geometric parameters and its response to vibration. We used a spherical finite element mechanical model based on shell theory and lubrication theory to model the PC's outer core. Specifically, we analyzed the effect of the following structural properties on the PC's frequency sensitivity: lamellar modulus (E), lamellar thickness (h), fluid viscosity (μ), PC outer radius (Ro), and number of lamellae (N). The frequency of peak strain amplification (henceforth "peak frequency") and frequency range over which strain amplification occurred (henceforth "bandwidth") increased with lamellar modulus or lamellar thickness and decreased with an increase in fluid viscosity or radius. All five structural parameters were combined into expressions for the relationship between the parameters and peak frequency, ωpeak=1.605×10-6N3.475(Eh/μRo), or bandwidth, B=1.747×10-6N3.951(Eh/μRo). Although further work is needed to understand how mechanical variability contributes to functional variability in PCs and how factors such as PC eccentricity also affect PC behavior, this study provides two simple expressions that can be used to predict the impact of structural or material changes with aging or disease on the frequency response of the PC.

Objective: Recent studies showed that intracortical microstimulation (ICMS) generates artificial sensations which can be utilized as somatosensory feedback in cortical neuroprostheses. To mimic the natural psychophysical response, ICMS parameters are modulated according to psychometric equivalence functions (PEFs). PEFs match the intensity levels of ICMS and mechanical stimuli, which elicit equal detection probabilities, but they typically do not include the frequency as a control variable. We aimed to establish frequency-dependent PEFs for vibrotactile stimulation of the glabrous skin and ICMS in the primary somatosensory cortex of awake freely behaving rats., Approach: We collected psychometric data for vibrotactile and ICMS detection at three stimulation frequencies (40, 60 and 80 Hz). The psychometric data were fitted with a model equation of two independent variables (stimulus intensity and frequency) and four subject-dependent parameters. For each rat, we constructed a separate PEF which was used to estimate the ICMS current amplitude for a given displacement amplitude and frequency. The ICMS frequency was set equal to the vibrotactile frequency. We validated the PEFs in a modified task which included randomly selected probe trials presented either with a vibrotactile or an ICMS stimulus, and also at frequencies and intensity levels not tested before., Main Results: The PEFs were generally successful in estimating the ICMS current intensities (no significant differences between vibrotactile and ICMS trials in Kolmogorov-Smirnov tests). Specifically, hit rates from both trial conditions were significantly correlated in 86% of the cases, and 52% of all data had perfect match in linear regression., Significance: The psychometric correspondence model presented in this study was constructed based on surface functions which define psychophysical detection probability as a function of stimulus intensity and frequency. Therefore, it may be used for the real-time modulation of the frequency and intensity of ICMS pulses in somatosensory neuroprostheses.

Background: Postoperative pain management is the part of shoulder surgery to improve patient satisfaction, start rehabilitation process rapidly and decrease for hospital stay. Various treatment modalities have been used for pain management, but they have some limitations, side effects and risks. Throughout intraoperative and postoperative period, nerve blocks have been used more popularly than others because of efficacy. For the regional nerve block, local anesthetic should be infiltrated close to the nerve for maximum effect. Consequently, aim of this study was to evaluate analgesic efficacy when catheters are placed with assistance of arthroscope to block suprascapular and axillary nerves in patients undergoing arthroscopic repair of rotator cuff under general anesthesia., Materials and Methods: 24 patients (5 males, 19 females; mean age: 54.3 years) who underwent arthroscopic repair of rotator cuff between June 2014 and September 2014 and were catheterized to block suprascapular and axillary nerves during shoulder arthroscopy were included in the study. Clinical outcomes were assessed using visual analog scale (VAS) scores preoperatively and at 0 h, 6 h, 12 h, 18 h, 24 h, and postoperative day 2., Results: Preoperative and postoperative 0 h, 6 h, 12 h, 18 h, 24 h, and day 2 mean VAS scores were 6.38 ± 0.77, 0.44 ± 0.42, 0.58 ± 0.42, 0.63 ± 0.40, 0.60 ± 0.44, 0.52 ± 0.42, and 1.55 ± 0.46, respectively. No statistical difference was found among 0 h, 6 h, 12 h, 18 h, and 24 h time points; however, comparison of postoperative day 2 and postoperative 0 h, 6 h, 12 h, 18h and 24 h VAS scores showed statistically significant difference ( P < 0.05). All patients were discharged at the end of 24 h with no complication. The mean time (in minutes) required for blocking suprascapular nerve and axillar nerve were 14.38 ± 3.21 and 3.75 ± 0.85, respectively., Conclusion: These results demonstrated that blocking two nerves with arthroscopic approach was an excellent pain management method in postoperative period. Accordingly, patients could recover rapidly and patients' satisfaction could be improved., Competing Interests: There are no conflicts of interest.

Streptococcus constellatus is a microorganism that lives commensally in the oropharyngeal region, urogenital region, and intestinal tract. However, it can cause infection in patients with certain predisposing factors. Rarely, this microorganism can cause a brain abscess. Thalamic localization of brain abscesses is much rarer than abscesses in other locations of the brain. Brain abscess caused by streptococcus constellatus are very rarely been reported in the literature. We present a rare case of a left-sided thalamic abscess caused by streptococcus constellatus in a 25-year-old male patient who was injured by shrapnel pieces in the head and who was malnourished. The patient was successfully treated by stereotactic aspiration and antibiotherapy., Competing Interests: The authors declare no competing interests.