[Calcified Amorphous Tumor Diagnosed After Stroke:Report of a Case].

Calcified amorphous tumor (CAT), a non-neoplastic tumor, is rare. Histopathologic features are the presence of calcified nodules in an amorphous background of fibrin. CAT is reported to be associated with renal dysfunction or hemodialysis, and possibly causes cerebral embolism. We report a case of CAT diagnosed after stroke. A 58-year-old male with a 2-year history of hemodialysis was diagnosed with an acute stroke, and was treated medically. Paralysis promptly improved, but transthoracic echocardiography revealed a tumor attached to the posterior mitral leaflet and dense mitral annular calcification. To prevent embolism due to the large tumor, we performed resection of the tumor. Pathological findings showed calcifications surrounded by amorphous fibrous tissue, indicating CAT. Postoperative course was uneventful.

Transient Electromyographic Responses by Isokinetic Torque Release during Mechanically Assisted Elbow Flexion.

Power assistance on joint torque may not be beneficial to all the related muscles. We investigated the effects of power assistance on torque release during isokinetic elbow flexion. An isokinetic dynamometer system was used to simulate dynamic elbow flexion with power assistance, which altered the exercise conditions of baseline isometric torque (greater and lower) and rotation speed (faster and slower) of the lever arm. Ten male right-handed participants performed exercise tasks using the system. We measured (1) the electromyogram (EMG) amplitudes of the biceps brachii (BB), brachioradialis (BR), and triceps brachii (TB) muscles, (2) torque output and its variability, and (3) the perceived assistance level. Transient responses of the objective measurements were analyzed by observing three time epochs before and after power assistance. Greater variability and lower perceived assistance levels were observed when greater torque was released at a faster rotation speed. The torque output and EMG amplitudes of BB and BR muscles decreased over time. However, EMG amplitudes in the TB muscle were relatively constant until 200 ms after power assistance resulting in greater muscle co-contraction. This could be attributed to the increased postural stability of the human musculature system when the external perturbation on joint movement occurred by power assistance, independent of exercise conditions.

[Pulmonary Adenocarcinoma in Situ with Positive Findings in Pleural Lavage Cytology].

We report a rare case of positive findings in pleural lavage cytology(PLC) in the patient with pulmonary adenocarcinoma in situ (AIS). A 78-year-old woman was presented with a 30 mm pure groundglass nodule (GGN) in the left upper lobe on chest computed tomography (CT). After 2 years follow- up, thoracoscopic surgery was performed to resect the nodule. PLC was performed before pulmonary resection. Histopathological diagnosis was 25 mm AIS. However, PLC showed positive findings of malignant cells. CT examination at 1 year and 6 months postoperatively showed pleural dissemination findings and the patient died of lung cancer at 3 years and 2 months postoperatively. PLC's contribution to TNM staging has not yet been clarified. The positive findings in PLC and large size of pure GGN were considered likely to be poor prognostic indicators.

[Acute Coronary Syndrome in a Patient with Giant Coronary Artery Aneurysm:Report of a Case].

Coronary artery aneurysm is a rare entity defined as expansion more than 1.5 times of normal coronary artery in diameter. A 77-year-old male was admitted to our hospital with a diagnosis of acute coronary syndrome and a giant right coronary artery aneurysm. Coronary angiography showed occlusion of the right coronary artery and significant stenosis of left anterior descending artery and left circumflex artery. Enhanced computed tomography( CT) showed a right coronary artery aneurysm with a diameter of 38 mm. Urgent coronary artery bypass grafting and coronary artery ligation proximal and distal to the aneurysm were performed. His postoperative course was uneventful.

Comparison of Phenotypes in Subcutaneous Fat and Perivascular Adipose Tissue Surrounding the Saphenous Vein in Coronary Artery Bypass Grafting.

BACKGROUND: The saphenous vein (SV) is used as an essential conduit in coronary artery bypass grafting (CABG), but the long-term patency of SV grafts is a crucial issue. The use of the novel "no-touch" technique of harvesting the SV together with its surrounding tissue has been reported to result in good long-term graft patency of SV grafts. We recently showed that perivascular adipose tissue (PVAT) surrounding the SV (SV-PVAT) had lower levels of metaflammation and consecutive adipose tissue remodeling than did PVAT surrounding the coronary artery. However, the difference between SV-PVAT and subcutaneous adipose tissue (SCAT) remains unclear.Methods and Results: Fat pads were sampled from 55 patients (38 men, 17 women; mean [±SD] age 71±8 years) with coronary artery disease who underwent elective CABG. Adipocyte size was significantly larger in SV-PVAT than SCAT. The extent of fibrosis was smaller in SV-PVAT than SCAT. There were no significant differences between SCAT and SV-PVAT in macrophage infiltration area, quantified by antibodies for CD68, CD11c, and CD206, or in gene expression levels of metaflammation-related markers. Expression patterns of adipocyte developmental and pattern-forming genes differed between SCAT and SV-PVAT. CONCLUSIONS: The properties of SV-PVAT are close to, but not the same as, those of SCAT, possibly resulting from inherent differences in adipocytes. SV-PVAT has healthy expansion with less fibrosis in fat than SCAT.

Users' adaptations to the proportional speed control of a motorised walker.

PURPOSE: Speed control is commonly used to regulate the forces applied by motorised walkers (MW) and there are often situations where the speed targeted deviates from the preferred walking speed of its users, such as when encouraging higher walking speeds and due to safety consideration. This study investigates the effects of different MW's target speeds on the selected walking speeds, force applied, perceived exertion, and gait of MW users during steady-state walking. MATERIALS AND METHODS: The spatiotemporal gait parameters and perceived exertion of twenty young healthy participants were measured as they walked at a comfortable, self-selected speed using a MW as it was controlled to target forward speeds of 0.6, 0.8, 1.0, 1.2, and 1.4 m s-1 as well as when no assistive force was applied by the MW. RESULTS: On average, users would walk slower when their "No Assist" walking speed is higher than the MW's speed target and vice versa. Additionally, the force applied to the MW is proportional to the difference in speed, either faster or slower, when compared to "No Assist". CONCLUSION: The user's exertion and the energy used by the MW are both minimised when target speed is close to the preferred walking speed of the user. Additionally, these findings suggest that the speed target can be used to change the walking speed of users but only to a certain extend and at the cost of higher perceived exertion.Implications for rehabilitationThe larger the difference between the target speed of the MW and the preferred walking speed of the user, the more likely the user is to push or pull on the MW.Users would push or pull on the MW with a force proportional to the difference from their preferred walking speed even when matching the MW's target speed.Users can be encouraged to walk at higher than preferred speeds, even though this would come at the cost of higher perceived exertion.

Backward Walking Styles and Impact on Spatiotemporal Gait Characteristics.

Forward walking (FW) is a common balance assessment tool. However, its sensitivity is limited by the ceiling effect. Reverse gait, such as backward walking (BW), has been reported to have more advantages than FW for balance assessment. Three factors related to postural instability (i.e., increased speeds, restricted arm swing, and reduced visual feedback) during BW were investigated to determine BW conditions that have the potential to predict falls. Three-dimensional analyses were used to analyze seven walking conditions. FW and BW at self-selected and fast speeds were analyzed to identify the effects of speed. Walking with normal arm swings, crossed arms, and abducted arms during BW was tested to determine the effects of arm position. BW with closed and open eyes was compared to investigate the effects of visual feedback. BW had a significantly shorter step length than FW at high speeds. When the arms were abducted, the stance phase (%) was significantly lower compared to when arms were crossed during BW. Moreover, BW with closed eyes revealed significantly higher mediolateral center of mass (COM) displacements than with open eyes. We observed that BW with fast speeds, a crossed arm position, and closed eyes has the potential to help assess fall risk because it requires higher balance ability through spatiotemporal and COM adjustment.

Effects of various handle shapes and surface profiles on the hand-arm responses and comfort during short-term exposure to handle vibration.

The magnitude of hand- (HTV) and wrist- (WTV) transmitted vibration can negatively impact upper limb responses even during short-term exposure. This study aimed to establish the effects of various handle-grip designs on the harmful impacts of vibration, sustained grip exertion, and unnatural posture. The primary focus was to investigate how using a handle grip and how three shapes with two surface profiles affect HTV, WTV, and forearm muscle activities during exposure. The secondary goal was to evaluate the immediate effects on fundamental hand functions, perceived discomfort/comfort, and perceived vibration level after exposure. The final objective was to assess which of the handle designs had the least harmful effects. Fourteen young male adults were recruited and asked to consistently grip a vibrating handle structure for 2 min while the primary parameters were recorded. Pre- and post-task measurements of secondary parameters were recorded on the six design conditions and one control condition (no handle grip). The study found that implementing a regular circular-smooth handle resulted in lower transmitted vibrations, leading to lower upper-limb discomfort, higher grip comfort, and lower perceived vibration. Additionally, shape significantly affected HTV, resulting in grip strength reduction, while surface profile did not influence transmitted vibrations but significantly impacted ring and small finger sensitivity, finger and hand discomfort, and grip comfort. Finally, forearm muscle activities were unaffected, and no significant interaction effects were observed. Circular handles also had the least negative impacts, and elliptic handles had the most negative impacts on the upper extremity because of the level of hand-handle contact stress and hand-grip effort. Meanwhile, the uneven distribution of vibration on the fingers and palm imposed by the rounded spikes on the patterned surface led to decreased finger sensitivity, higher discomfort, and lower grip comfort. Therefore, when machine operation involves moderate grip exertion, pronated forearm posture, and short-term handle vibration exposure, implementing a hard-solid handle with less hand-handle contact area, less grip effort, and even texture is recommended.

The effect of horizontal forces from a Smart Walker on gait and perceived exertion.

Increasingly, electric motors are being incorporated into wheeled walkers to implement various smart features to better assist their users physically. These modified walkers, known as Smart Walkers, use their electric motors to generate horizontal forces that can be used to reduce the physical load for walking, prevent falls and provide navigation support. However, these forces can also alter gait and may inadvertently increase the exertion of the users. This study aims to describe the effects of assistive and resistive horizontal forces (from -18.47 N to 27.70 N) from a Smart Walker on gait and perceived exertion of its users during steady-state walking. Self-selected comfortable walking speed, cadence, stride length, double support phase and ratings of perceived exertion (RPE) were significantly affected and different effects were found for resistive force, relatively low assistive force and high assistive force. With increasing force from -18.47 N to 0 N, RPE decreased and the users walked with lower double support time. From 0 N to 9.23 N, RPE continued to decrease to its lowest point while gait parameters remained constant. Further increasing force up to 27.70 N increased RPE and led to the users to choose to walk at higher speeds. This study demonstrates that users adapt their gait significantly to the forces applied and relatively high constant forces, whether assistive or resistive, will increase perceived exertion. Hence, these need to be carefully considered when developing Smart Walkers in order to provide safe and effective support to its users.

Different flooring surfaces affect infants' crawling performance.

This study assessed the influence of different types of flooring on infants' crawling motion patterns and performance. Each participating infant (range: 8.7-12.4 months) was encouraged to crawl on a tatami mat made of woven straw as well as other flooring types such as hardwood, carpet, and joint mat. Material tests were conducted to quantify the friction and shock absorption of the flooring. A three-dimensional motion capture system was used to measure spatiotemporal and kinematic variables during hands-and-knees crawling. An increased crawling rate was associated with a faster cadence of cyclic arm movements, but not with crawling stride length. Hardwood flooring had a significantly lower crawling rate and longer duration of hand-floor contact than tatami, while the crawling stride length and range of motion of joint movements were hardly affected by flooring type. The results of this study suggest a drawback of hardwood flooring in terms of infants' effective quadrupedal locomotion.

[Coronary Aneurysm with Fistula].

We successfully treated two rare cases of coronary aneurysm with fistula. Case 1;A 65-year-old female referred to our hospital with the coronary aneurysm and fistula. Right coronary aneurysm with fistula leading to coronary sinus was observed. Coronary bypass surgery using a saphenous vein to #4PD was performed, and two right ventricle branches were reconstructed. Coronary aneurysm was resected. Case 2;A 46-year-old male was admitted with chest discomfort. Coronary aneurysm with fistula from the left main trunk to left ventricle was demonstrated. Ligation of the coronary artery aneurysm and suture closure of the entry site to the left ventricle was performed. Both patients had uneventful recovery.

[Third Tricuspid Valve Replacement:Report of a Case].

A 79-year-old man underwent tricuspid valve replacement (TVR) with a bovine pericardial bioprosthesis, Carpentier-Edwards Perimount (CEP), for tricuspid regurgitation 27 years earlier. Twenty-one years after the first operation, he underwent re-TVR with a bovine pericardial bioprosthesis, Magna Mitral Ease, due to prosthetic valve dysfunction. Since the prosthetic valve dysfunction progressed again, the third TVR was performed six years after the second operation. The findings of the resected bioprosthesis showed sclerosis of the septal cusp, and pannus formation between the septal and posterior cusps. For the third TVR, the porcine bioprosthesis Epic was used. Neither transvalvular nor perivalvular leakage was observed postoperatively, and the patient was discharged without any complications.

[Papillary Fibroelastoma Arising from the Left Atrial Wall:Report of a Case].

Papillary fibroelastoma (PFE) is a rare benign cardiac tumor generally arising from the valvular endocardium. We report an extremely rare case of PFE arising from the left atrial wall. A 70-year-old male patient was admitted to our hospital with a diagnosis of left atrial tumor. Echocardiography and enhanced computed tomography showed an approximately 14 mm mass on the left atrial wall. Moreover, the magnetic resonance imaging showed hyperintenseness on a T2-weighted image. We diagnosed the tumor as a myxoma. Intraoperatively, we found a mobile tumor on the left atrial wall. It had a sea anemone-like appearance and was suspected to be PFE. We performed the tumor resection including the left atrial wall. Histological examination confirmed PFE. His postoperative course was uneventful.

Motor control characteristics of upper limbs in response to assistive forces during bilateral tasks.

Most research on power assist suits (PASs) that concerned PAS-human interactions has used human physical reactions as criteria to evaluate the mechanical function, however, with minimal emphasis on human reactions in response to PASs. In this study, we focused on the physiological responses of the upper limbs including muscle activity of the biceps brachii and the triceps brachii, co-activation, force steadiness (CV) and rated perceived exertion (RPE) to various patterns of bilateral assistive force, such as unilateral assistance (L0% & R67% [% = percentage of workload force, L = left arm, R = right arm], L67% & R0%, L0% & R33%, L33% & R0%), symmetrical (L0% & R0%, L33% & R33%, L67% & R67%) and asymmetrical bilateral assistance (L33% & R67%, L67% & R33%), during bilateral isometric force-matching tasks. The results showed a similar muscular response of the two arms to bilateral assistive conditions, and the muscle activity of the arm that was being observed decreased only when the assistive force that applied on itself increased, indicating that both arms may have adopted similar but independent motor control mechanisms to acclimate to the bilateral assistive forces. Comparison between the two unilateral assistances (L0% & R33% and L33% & R0%) and the two asymmetrical bilateral assistances (L33% & R67%, L67% & R33%) showed no significant differences in muscular responses, CV and RPE, indicating that bilateral assistances with bilateral interchanged assistive levels may be equally effective regardless of which arm the higher assistive force is applied to. Comparison between unilateral and symmetrical assistive conditions that have similar overall workloads (L67% & R0%, L33% & R33%, L0% & R67%) showed a lower CV and RPE score at symmetrical assistance compared with unilateral assistance, suggesting that assisting both arms with the same level simultaneously improves task performances compared with applying the assistive force to only one arm.

Changes in Muscle Activity in Response to Assistive Force during Isometric Elbow Flexion.

This study investigated the muscle activity and force variability in response to perturbation of assistive force during isometric elbow flexion. Sixteen healthy right-handed young men (age: 22.0 ± 1.1 years; height: 171.9 ± 4.8 cm; weight 68.4 ± 11.2 kg) were recruited and the muscle activity of biceps brachii and triceps brachii were assessed using surface electromyography. Workload force and assistive force applied on isometric elbow flexion significantly affected the changes in both biceps and triceps muscle activities. A higher assistive force was shown to result in reduced biceps muscle activity compared to the unassisted period. In contrast, the efficiency of the assistive force acting on the biceps decreased as the assistive force increased. In general, the force variability of the biceps muscle remained approximately the same at lower workload force conditions than that at higher workload force conditions. In conclusion, higher assistive force may not yield a higher performance efficiency in human-assistive force interaction.

Effects of mechanical assistance on muscle activity and motor performance during isometric elbow flexion.

Mechanical assistance on joint movement is generally beneficial; however, its effects on cooperative performance and muscle activity needs to be further explored. This study examined how motor performance and muscle activity are altered when mechanical assistance is provided during isometric force control of ramp-down and hold phases. Thirteen right-handed participants (age: 24.7 ± 1.8 years) performed trajectory tracking tasks. Participants were asked to maintain the reference magnitude of 47 N (REF) during isometric elbow flexion. The force was released to a step-down magnitude of either 75% REF or 50% REF and maintained, with and without mechanical assistance. The ramp-down durations of force release were set to 0.5, 2.5, or 5.0 s. Throughout the experiment, we measured the following: (1) the force output using load cells to compute force variability and overshoot ratio; (2) peak perturbation on the elbow movement using an accelerometer; (3) the surface electromyography (sEMG) from biceps brachii and triceps brachii muscles; and (4) EMG oscillation from the biceps brachii muscle in the bandwidth of 15-45 Hz. Our results indicated that mechanical assistance, which involved greater peak perturbation, demonstrated lower force variability than non-assistance (p < 0.01), while EMG oscillation in the biceps brachii muscle from 15 to 45 Hz was increased (p < 0.05). These findings imply that if assistive force is provided during isometric force control, the central nervous system actively tries to stabilize motor performance by controlling specific motor unit activity in the agonist muscle.

Force and electromyography responses during isometric force release of different rates and step-down magnitudes.

This study investigated motor responses of force release during isometric elbow flexion by comparing effects of different ramp durations and step-down magnitudes. Twelve right-handed participants (age: 23.1 ±â€¯1.1) performed trajectory tracking tasks. Participants were instructed to release their force from the reference magnitude (REF; 40% of maximal voluntary contraction force) to a step-down magnitude of 67% REF or 33% REF and maintain the released magnitude. Force release was guided by ramp durations of either 1 s or 5 s. Electromyography of the biceps brachii and triceps brachii was performed during the experimental task, and the co-contraction ratio was evaluated. Force output was recorded to evaluate the parameters of motor performance, such as force variability and overshoot ratio. Although a longer ramp duration of 5 s decreased the force variability and overshoot ratio than did shorter ramp duration of 1 s, higher perceived exertion and co-contraction ratio were followed. Force variability was greater when force was released to the step-down magnitude of 33% REF than that when the magnitude was 67% REF, however, the overshoot ratio showed opposite results. This study provided evidence proving that motor control strategies adopted for force release were affected by both duration and step-down magnitude. In particular, it implies that different control strategies are required according to the level of step-down magnitude with a relatively short ramp duration.

An overview of hand postures and aging on morphological changes of the median nerve.

BACKGROUND: High-resolution ultrasound is being widely used in carpal tunnel examination to understand morphological and biomechanical characteristics of the median nerve and surrounding anatomy structures. MAIN BODY: Healthy young and elderly men were recruited. The median nerve at proximal wrist region was examined by ultrasound imaging technique. A total of seven wrist angle was examined. Generally, the median nerve cross-sectional area of the elderly group is significantly larger than the young group. SHORT CONCLUSION: Wrist posture in greater flexion or extension caused a larger decrease in the median nerve cross-sectional area across both groups.

[Pulmonary Non-tuberculous Mycobacteriosis Complicated with Pulmonary Large Cell Neuroendocrine Carcinoma;Report of a Case].

A 64-year-old man with pulmonary non-tuberculous mycobacteriosis(pulmonary NTM) who had been treated by antituberculous chemotherapy, developed a new nodule of 8 mm in size in the segment 3 of the right upper lobe. The cavity of 4.0 cm in size in the segment 1+2 of the left upper lobe due to Mycobacterium avium infection was preexisted. Radiologically, new nodule of the right lung was suspected to be lung cancer. Left upper lobe apical trisegmentectomy was performed at first. Three months later, enlarging of the right lung nodule with increased fluoro-2-deoxy-D-glucose(FDG) activity was noted, and the diagnosis of lung cancer was made by transbronchial lung biopsy(TBLB). Then, right upper lobectomy with systematic nodal dissection were performed.

Deformation of the median nerve at different finger postures and wrist angles.

BACKGROUND: The objective of this study was to evaluate the changes of the median nerve cross-sectional area (MNCSA) and diameters of the median nerve at different finger postures and wrist angles. METHODS: Twenty-five healthy male participants were recruited in this study. The median nerve at wrist crease was examined at six finger postures, and repeated with the wrist in 30° flexion, neutral (0°), and 30° extension. The six finger postures are relaxed, straight finger, hook, full fist, tabletop, and straight fist. RESULTS: The main effects of both finger postures and wrist angles are significant (p < 0.05) on changes of the MNCSA. Different finger tendon gliding postures cause a change in the MNCSA. Furthermore, wrist flexion and extension cause higher deformation of the MNCSA at different finger postures. DISCUSSION: The median nerve parameters such as MNCSA and diameter were altered by a change in wrist angle and finger posture. The results may help to understand the direct biomechanical stresses on the median nerve by different wrist-finger activities.