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In clinical practice, clinicians often meet patients suffering from mid-back pain. One of the possible causes of mid-back pain is penetrating atherosclerotic aortic ulcer (PAU), but the diagnosis is often delayed owing to its low incidence. Here, we report a patient with mid-back pain due to a PAU, who was diagnosed after receiving several procedures for reducing musculoskeletal pain. A 65-year-old man visited our pain clinic for mid-back pain [numeric rating scale (NRS): 7] experienced for 2 months. The pain was radiated to the lateral chest area and was aggravated when in the supine and standing positions. Trigger point injection, medial branch block, and pulsed radiofrequency were ineffective. The cardiac evaluation and abdominal computed tomography (CT) results showed no abnormalities. On CT aortography at 3 months after pain onset, intraluminal thrombus, multiple ruptured PAUs, and aneurysmal change of the descending thoracic aorta were found. Accordingly, PAU was diagnosed as the origin of the patient's pain. We administered nicardipine with a rate of 1.15 mcg/kg/min and esmolol with a rate of 100 mcg/kg/min for controlling the systolic blood pressure. In addition, an anticoagulant was administered orally. To alleviate the pain, we further administered intravenous opioid. Approximately 6 h after, the systolic blood pressure decreased to 100-120 mmHg, and the pain rating decreased to NRS 1. Two weeks after the discharge, the patient's pain rating was sustained at NRS 1. Clinicians should be aware of the fact that PAU can be a cause of mid-back or chest pain.

The effectiveness of the chin tuck maneuver is still controversial, despite being widely used in clinical practice. The chin tuck maneuver has been shown to be able to reduce or eliminate aspiration in a group of patients with a number of favorable conditions, but its effectiveness in preventing or managing penetration remains unclear. This study was designed to investigate whether the chin tuck maneuver is effective in reducing penetration. Images from a videofluoroscopic swallowing study (VFSS) taken from 76 patients with penetration were collected and reviewed retrospectively. The severity of penetration was assessed by the penetration ratio (ratio of the penetration depth to the length of the epiglottis) measured and calculated from the images in which the deepest penetration was observed. The penetration ratio was significantly decreased in the chin tuck posture compared with the ratio in the neutral position (p = 0.001). Significant reducing effect was observed in 26 (34.2%) out of 76 patients. When comparing other parameters of VFSS, residues in the vallecular and pyriformis sinuses were less severe in the effective group. Chin tuck significantly decreased residues in both effective and ineffective group. The results demonstrate that the chin tuck maneuver can reduce penetration, but its effectiveness is limited.

Objective Minocycline is known to reduce microglial activation, suggesting that it may reduce neuropathic pain. We reviewed studies in humans that evaluated the effectiveness of minocycline in alleviating neuropathic pain. Methods We searched the PubMed, Embase, Cochrane library, and SCOPUS databases for papers published before January 06, 2021, using the search words minocycline and pain. The inclusion criteria for the selection of articles were (1) minocycline administered to humans and (2) minocycline administered to control neuropathic pain. Results The primary literature search yielded 2299 relevant papers. Based on the assessment of the titles, abstracts, and full-text, nine publications were selected for this review. Only four of the nine studies showed a positive pain-reducing outcome after minocycline administration. Two of the three studies on chemotherapy-induced neuropathic pain showed a positive pain-reducing effect. Minocycline was effective in controlling pain from diabetic and leprotic neuropathies. However, minocycline was not effective in controlling lumbar radicular pain and pain resolution after carpal tunnel release. Conclusion Our review provides evidence that minocycline may have some potential for reducing neuropathic pain. Further high-quality studies need to be conducted to validate this potential.

Spine diseases are common and exhibit several causes, including degeneration, trauma, congenital issues, and other specific factors. Most people experience a variety of symptoms of spine diseases during their lifetime that are occasionally managed with conservative or surgical treatments. Accurate diagnosis of the spine pathology is essential for the appropriate management of spine disease, and various imaging modalities can be used for the diagnosis, including radiography, computed tomography (CT), magnetic resonance imaging (MRI), and other studies such as EOS, bone scan, single photon emission CT/CT, and electrophysiologic test. Patient (or case)-specific selection of the diagnostic modality is crucial; thus, we should be aware of basic information and approaches of the diagnostic modalities. In this review, we discuss in detail, about diagnostic modalities (radiography, CT, MRI, electrophysiologic study, and others) that are widely used for spine disease.

Objective To investigate the comprehensive outcomes in aphasic patients, including their cognitive and functional status after ischemic or hemorrhagic stroke. It also aimed to clarify whether aphasia is a prognostic factor for cognitive and functional improvements in stroke patients.Methods Sixty-seven ischemic or hemorrhagic stroke patients in the subacute stage who had been diagnosed with aphasia using the Korean version of Frenchay Aphasia Screening Test (K-FAST) were included in the study. Forty-six stroke patients without aphasia were used as controls. All patients were examined with the Korean version of the Western Aphasia Battery (K-WAB). Cognitive and functional assessments of the patients including the Korean version of Mini-Mental State Examination (K-MMSE), and the Korean version of Modified Barthel Index (K-MBI) were performed during admission and 4 weeks after the initial assessments.Results The initial and follow-up total K-MMSE and K-MBI scores were significantly lower in aphasic patients than in non-aphasic controls. The K-WAB scores highly correlated with the total K-MMSE scores at the follow-up stage in all aphasic stroke patients. The K-WAB scores moderately correlated with the follow-up scores of the K-MBI in ischemic stroke patients but not in hemorrhagic stroke patients.Conclusion Aphasia influences the cognitive and functional status of stroke patients and has a greater impact on cognitive improvement. Aphasia severity can be one of the prognostic factors for cognitive status in aphasic patients with stroke.

Poststroke depression (PSD) is a major psychiatric disorder that develops after stroke; however, whether PSD treatment improves cognitive and functional impairments is not clearly understood. We reviewed data from 31 subjects with PSD and 34 age-matched controls without PSD; all subjects underwent neurological, cognitive, and functional assessments, including the National Institutes of Health Stroke Scale (NIHSS), the Korean version of the Mini-Mental Status Examination (K-MMSE), computerized neurocognitive test (CNT), the Korean version of the Modified Barthel Index (K-MBI), and functional independence measure (FIM) at admission to the rehabilitation unit in the subacute stage following stroke and 4 weeks after initial assessments. Machine learning methods, such as support vector machine, k-nearest neighbors, random forest, voting ensemble models, and statistical analysis using logistic regression were performed. PSD was successfully predicted using a support vector machine with a radial basis function kernel function (area under curve (AUC) = 0.711, accuracy = 0.700). PSD prognoses could be predicted using a support vector machine linear algorithm (AUC = 0.830, accuracy = 0.771). The statistical method did not have a better AUC than that of machine learning algorithms. We concluded that the occurrence and prognosis of PSD in stroke patients can be predicted effectively based on patients’ cognitive and functional statuses using machine learning algorithms.

Unsteady turbulent flow simulations were performed based on the Reynolds-averaged Navier–Stokes (RANS) equations to investigate flow oscillation due to three-dimensional (3D) configuration of a Mach 1.5 supersonic open cavity flow with a length-to-depth ratio of 3. Two-dimensional (2D) and 3D unsteady simulation results were analyzed and compared with experimental data and Rossiter’s empirical prediction data. The three-dimensional cavity width-to-depth ratio (W/D) was 1, 3.8 and 7.6. Computational results indicated that pressure oscillation in the 2D flow was generated by a single-flow structure, whereas a multiple-flow structure generated multiple oscillation peaks in the 3D flow. The flow structure in the 3D cavity was investigated. For the 2D flow case, the cavity internal pressure wave was directly synchronized with the free shear layer. In the 3D flow case, an unstable spanwise flow due to the sidewall was observed. This spanwise fluctuation produced additional pressure oscillations coupled with the streamwise internal pressure wave. The numerical results indicate that the spanwise flow reduces the propagation speed of the internal pressure waves and the intensity of the corresponding pressure fluctuation.

The coronavirus disease (COVID-19) has become a global pandemic. Invasive mechanical ventilation is recommended for the management of patients with COVID-19 who have severe respiratory symptoms. However, various complications can develop after its use. The efficient and appropriate management of patients requires the identification of factors associated with an aggravation of COVID-19 respiratory symptoms to a degree where invasive mechanical ventilation becomes necessary, thereby enabling clinicians to prevent such ventilation. This retrospective study included 138 inpatients with COVID-19 at a tertiary hospital. We evaluated the differences in the demographic and clinical data between 27 patients who required invasive mechanical ventilation and 111 patients who did not. Multivariate logistic regression analysis indicated that the duration of fever, national early warning score (NEWS), and lactate dehydrogenase (LDH) levels on admission were significantly associated with invasive mechanical ventilation in this cohort. The optimal cut-off values were: fever duration ≥1 day (sensitivity 100.0%, specificity 54.95%), NEWS ≥7 (sensitivity 72.73%, specificity 92.52%), and LDH >810 mg/dL (sensitivity 56.0%, specificity 90.29%). These findings can assist in the early identification of patients who will require invasive mechanical ventilation. Further studies in larger patient populations are recommended to validate our findings.

Neuralgic amyotrophy (NA) is markedly underdiagnosed in clinical practice, and its actual incidence rate is about 1 per 1000 per year. In the current article, we provide an overview of essential information about NA, including the etiology, clinical manifestations, diagnostic investigations, differential diagnosis, treatment, and prognosis. The causes of NA are multifactorial and include immunological, mechanical, or genetic factors. Typical clinical findings are a sudden onset of pain in the shoulder region, followed by patchy flaccid paralysis of muscles in the shoulder and/or arm. A diagnosis of NA is based on a patient’s clinical history and physical examination. Gadolinium-enhanced magnetic resonance imaging and high-resolution magnetic resonance neurography are useful for confirming the diagnosis and choosing the appropriate treatment. However, before a diagnosis of NA is confirmed, other disorders with similar symptoms, such as cervical radiculopathy or rotator cuff tear, need to be ruled out. The prognosis of NA depends on the degree of axonal damage. In conclusion, many patients with motor weakness and pain are encountered in clinical practice, and some of these patients will exhibit NA. It is important that clinicians understand the key features of this disorder to avoid misdiagnosis.

Exercise training is a traditional method to maximize remaining function in patients with spinal cord injury (SCI), but the exact mechanism by which exercise promotes recovery after SCI has not been identified, whether exercise truly has a beneficial effect on SCI also remains unclear. Previously, we showed that epigenetic changes in the brain motor cortex occur after SCI and that a treatment leading to epigenetic modulation effectively promotes functional recovery after SCI. We aimed to determine how exercise induces functional improvement in rats subjected to SCI and whether epigenetic changes are engaged in the effects of exercise. A spinal cord contusion model was established in rats, which were then subjected to treadmill exercise for 12 weeks. We found that the size of the lesion cavity and the number of macrophages were decreased more in the exercise group than in the control group after 12 weeks of injury. Immunofluorescence and DNA dot blot analysis revealed that levels of 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC) in the brain motor cortex were increased after exercise. Accordingly, the expression of ten-eleven translocation (Tet) family members (Tet1, Tet2, and Tet3) in the brain motor cortex also elevated. However, no macrophage polarization was induced by exercise. Locomotor function, including Basso, Beattie, and Bresnahan (BBB) and ladder scores, also improved in the exercise group compared to the control group. We concluded that treadmill exercise facilitates functional recovery in rats with SCI, and mechanistically epigenetic changes in the brain motor cortex may contribute to exercise-induced improvements.

Profilin-1 (PFN1) regulates actin polymerization and cytoskeletal growth. Despite the essential roles of PFN1 in cell integration, its subcellular function in keratinocyte has not been elucidated yet. Here we characterize the specific regulation of PFN1 in DNA damage response and repair machinery. PFN1 depletion accelerated DNA damage-mediated apoptosis exhibiting PTEN loss of function instigated by increased phosphorylated inactivation followed by high levels of AKT activation. PFN1 changed its predominant cytoplasmic localization to the nucleus upon DNA damage and subsequently restored the cytoplasmic compartment during the recovery time. Even though γH2AX was recruited at the sites of DNA double strand breaks in response to DNA damage, PFN1-deficient cells failed to recruit DNA repair factors, whereas control cells exhibited significant increases of these genes. Additionally, PFN1 depletion resulted in disruption of PTEN-AKT cascade upon DNA damage and CHK1-mediated cell cycle arrest was not recovered even after the recovery time exhibiting γH2AX accumulation. This might suggest PFN1 roles in regulating DNA damage response and repair machinery to protect cells from DNA damage. Future studies addressing the crosstalk and regulation of PTEN-related DNA damage sensing and repair pathway choice by PFN1 may further aid to identify new mechanistic insights for various DNA repair disorders. Supplementary Information The online version contains supplementary material available at 10.1007/s11033-021-06210-6.

The obturator nerve lies deep within the pelvis, and it can be damaged by direct injury during surgery. In this study, nerve conduction was used to confirm an obturator nerve injury in a patient who presented with hip adductor weakness following gynecological surgery for endometrial cancer. A 56-year-old woman complained of weakness in the right adductor muscles after a laparoscopic hysterectomy due to endometrial cancer. Seven days after surgery, the degree of weakness of the right hip adductor was Medical Research Council (MRC) Scale 1; thus, a nerve conduction velocity test was conducted. To obtain the compound muscle action potentials of the obturator nerve, stimulation was performed (1.5 cm inferior and 1.5 cm lateral to the pubic tubercle) with a surface electrical simulator and recording (midpoint of the right medial thigh) of the adductor muscles. The compound muscle action potentials of the right obturator nerve showed lower amplitude (left side: 2.7 mV vs. right side: 0.3 mV) and delayed onset latency (left side: 3.2 ms vs. right side: 2.2 ms). These results indicate a partial right obturator neuropathy. Therefore, nerve conduction could be useful to diagnose an early-stage obturator nerve injury and provide information on the degree of damage.

Objective To investigate the effect of repetitive transcranial magnetic stimulation (rTMS) on neurological and functional recovery in patients with central cord syndrome (CCS) involving the upper extremities between the treated and non-treated sides of the treated group and whether the outcomes are comparable to that of the untreated control group. Methods Nineteen CCS patients were treated with high-frequency (20 Hz) rTMS over the motor cortex for 5 days. The stimulation side was randomly selected, and all the subjects received conventional occupational therapy during the rTMS-treatment period. Twenty CCS patients who did not receive rTMS were considered as controls. Clinical assessments, including those by the International Standard for Neurological Classification of Spinal Cord Injury, the Jebsen-Taylor Hand Function Test, and the O'Connor Finger Dexterity Test were performed initially and followed up for 1 month after rTMS treatment or 5 weeks after initial assessments. Results The motor scores for upper extremities were increased and the number of improved cases was greater for the treated side in rTMS-treated patients than for the non-treated side in rTMS-treated patients or controls. The improved cases for writing time and score measured on the Jebsen-Taylor Hand Function Test were also significantly greater in number on the rTMS-treated side compared with the non-treated side and controls. There were no adverse effects during rTMS therapy or the follow-up period. Conclusion The results of the application of high-frequency rTMS treatment to CCS patients suggest that rTMS can enhance the motor recovery and functional fine motor task performance of the upper extremities in such individuals.

To enhance the flight endurance of a HALE UAV, the main wing of the UAV should have a high aspect ratio and low structural weight. Since a main wing constructed with the thin walled and slender components needed for low structural weight can suffer catastrophic failure during flight, it is important to develop a light-weight airframe without sacrificing structural integrity. In this paper, the design of the main wing of the HALE UAV was conducted using spars which were composed of a carbon–epoxy cylindrical tube and bulkheads to achieve both the weight reduction and structural integrity. The spars were sized using numerical analysis considering non-linear deformation under bending moment. Static strength testing of the wing was conducted under the most critical load condition. Then, the experimental results obtained for the wing were compared to the analytical result from the non-linear finite-element analysis. It was found that the developed main wing reduced its structural weight without any failure under the ultimate load condition of the static strength testing.

In this study, an innovative smart concrete block (SCB) using a smart ultra-high-performance concrete integrated with the multiple channel wireless sensing system was developed to monitor the loss of pre-stressing stress and the partial damage of pre-stressing steel (PS) tendons. The electromechanical behavior of the four corners of the SCB as a function of the compressive stress was investigated. The fractional change in resistivity (FCR) at the four corners of the SCB linearly increased with increasing compressive stress. The different FCRs at the four corners of the SCB could be successfully utilized to identify the partial damage and/or eccentric load position of the PS tendon. An SCB with a 20 mm-gauge length was suitable for monitoring the loss of pre-stressing stress because of higher stress sensitive coefficient (0.19–0.23%/MPa) than that (0.08–0.20%/MPa) of an SCB with a 40 mm-gauge length.

In this study, transient response analysis of a Mode III interface crack between a piezoelectric layer and a functionally graded orthotropic material (FGOM) layer is conducted using integral transform techniques. Material properties of the FGOM layer change continuously along the layer thickness and two layers are connected weak-discontinuously. Laplace and Fourier transforms are applied to solve the problem, and the problem is then expressed by a Fredholm integral equation of the second kind. It is found that the followings are beneficial to impede transient fracture of the interface crack between piezoelectric layer and FGOM layer: (a) an increase of shear moduli of the FGOM from the interface to the lower free surface; (b) an increase of the gradient of shear moduli, a decrease of ratio of shear moduli, the electric boundary condition EBC I of the piezoelectric layer in the case of increase of shear moduli of the FGOM from the interface to the lower free surface; (c) an increase of thickness of the layers.

OBJECTIVE To investigate the factors related to upper extremity functional improvement following inhibitory repetitive transcranial magnetic stimulation (rTMS) in stroke patients. METHODS Forty-one stroke patients received low-frequency rTMS over the contralesional hemisphere according to a standard protocol, in addition to conventional physical and occupational therapy. The rTMS-treated patients were divided into two groups according to their responsiveness to rTMS measured by the self-care score of the Korean version of Modified Barthel Index (K-MBI): responded group (n=19) and non-responded group (n=22). Forty-one age-matched stroke patients who had not received rTMS served as controls. Neurological, cognitive and functional assessments were performed before rTMS and 4 weeks after rTMS treatment. RESULTS Among the rTMS-treated patients, the responded group was significantly younger than the non-responded group (51.6±10.5 years and 65.5±13.7 years, respectively; p=0.001). Four weeks after rTMS, the National Institutes of Health Stroke Scale, the Brunnstrom recovery stage and upper extremity muscle power scores were significantly more improved in the responded group than in the control group. Besides the self-care score, the mobility score of the K-MBI was also more improved in the responded group than in the non-responded group or controls. CONCLUSION Age is the most obvious factor determining upper extremity functional responsiveness to low-frequency rTMS in stroke patients.

Aircraft needs high lift-to-drag ratio and weight reduction of the structure for long endurance flight with a small power. Generally high aspect ratio wing is applied to HALE(High Altitude Long Endurance) aircraft. Also high modulus, and high strength CFRP(Carbon Fiber Reinforced Plastic) has been used in primary structures. and thin mylar(membrane material) film has been applied to skin of wing. As a result, wing is more flexible than the other structures. and the stiffness of thin mylar film has an affect on dynamic stability. In this study, the membrane characteristic of mylar film has been simulated using nonlinear gap elements. And equivalent modeling method using shell elements is presented using the nonlinear simulation result. The linear equivalent model has verified using the results of nonlinear membrane method. Proposed linear equivalent shell model has applied to mode analysis for estimate the effect of mylar mechanical properties on natural frequency.