BACKGROUND: During cardiogenesis, cardiac cells receive various stimuli, such as biomechanical and chemical cues, from the surrounding microenvironment, and these signals induce the maturation of heart cells. Mechanical force, especially tensile force in the heart, is one of the key stimuli that induce cardiomyocyte (CM) maturation through mechanotransduction, a process through which physical cues are transformed into biological responses. However, the effects and mechanisms of tensile force on cell maturation are poorly studied. METHODS: In this study, we developed a cyclic stretch system that mimics the mechanical environment of the heart by loading tensile force to human-induced pluripotent stem cell (hiPSC)-derived CMs. hiPSC-CMs cultured with the cyclic stretch system analyzed morphological change, immunofluorescent staining, expression of maturation markers in mRNA, and beating properties compared to static cultures. RESULTS: hiPSC-CMs cultured with the cyclic stretch system showed increased cell alignment, sarcomere length and expression of maturation markers in mRNA, such as TNNI3, MYL2 and TTN, compared to static cultures. Especially, the expression of genes related to nuclear mechanotransduction, such as Yap1, Lamin A/C, plectin, and desmin, was increased in the cyclically stretched hiPSC-CMs. Furthermore, the volume of the nucleus was increased by as much as 120% in the cyclic stretch group. CONCLUSION These results revealed that nuclear mechanotransduction induced by tensile force is involved in CM maturation. Together, these findings provide novel evidence suggesting that nuclear mechanotransduction induced by tensile force is involved in the regulation of cardiac maturation.

Musculoskeletal symptoms, such as muscle weakness, stiffness and pain, are observed frequently in patients with hypothyroidism. In theory, hypothyroidism can cause weakness of the swallowing muscles, but dysphagia associated with hypothyroidism-associated myopathy has not been reported. The present case involved a 51-year-old man who experienced acute onset of severe dysphagia with aspiration pneumonia. A video fluoroscopic swallowing study and fiberoscopic endoscopic evaluation of swallowing revealed pharyngo-laryngeal function impairment. With a prior history of subclinical hypothyroidism and clinical symptoms such as proximal limb weakness, further evaluation involving a hormonal study, electrodiagnostic study, and histopathology assessment revealed myopathy. Hormone replacement therapy was started and the patient recovered within three weeks of treatment and was taking a regular diet. In conclusion, this study suggests that it is necessary to consider further evaluations to determine if hypothyroid myopathy is involved in the case of unknown origin dysphagia accompanied by hypothyroid myopathy.
Deglutition Disorders ; Deglutition* ; Diet ; Extremities ; Hormone Replacement Therapy ; Humans ; Hypothyroidism ; Middle Aged ; Muscle Weakness ; Muscles ; Muscular Diseases* ; Pneumonia, Aspiration

Hemispatial neglect is a symptom where patients do not show response to stimuli on the contralesional side of their brain lesion. Although it is most common in the context of hemispheric stroke, several pathological processes including neurodegenerative disease, neoplasia, and trauma may cause this. Prevalence of hemispatial neglect is unknown and rarely reported among patients with hypoxic brain injury. Also, hemispatial neglect accompanying neglect dyslexia is rather hard to be recognized and symptoms involving numbers are exceptionally rare. We report a patient with hypoxic brain injury following cardiac arrest who showed signs of neglect dyslexia for numbers that provided a primary clue for the diagnosis of left hemispatial neglect. Early detection of different forms of cognitive dysfunction of hypoxic brain injury is highly essential in providing early neurorehabilitation for better prognosis.

Bertolotti’s syndrome (BS) refers to chronic low back pain (LBP) associated with lumbosacral transitional vertebrae (LSTV). Many studies suggest that the anomalous articulation alters biomechanics, resulting in discomfort on the ipsilateral side. Herein, we present an unusual case of BS presenting pain on the non-articulated side. A 46-year-old man visited our clinic with history of chronic LBP, refractory to treatment of analgesics, modalities and manual therapies. Electrodiagnostic studies showed no evidence of lumbosacral radiculopathy. Radiographies noted unilateral pseudoarticulation of L5∼S1 vertebrae, on the contralateral side of his pain. The pain improved dramatically after sacroiliac joint block and facet joint block with iliolumbar ligament infiltration on the non-articulated side. Clinicians should be cautious that the unaffected joint in BS may serve an important role in altered lumbopelvic biomechanism, since it might eventually lead to intractable chronic LBP when overlooked.

Hemispatial neglect is a symptom where patients do not show response to stimuli on the contralesional side of their brain lesion. Although it is most common in the context of hemispheric stroke, several pathological processes including neurodegenerative disease, neoplasia, and trauma may cause this. Prevalence of hemispatial neglect is unknown and rarely reported among patients with hypoxic brain injury. Also, hemispatial neglect accompanying neglect dyslexia is rather hard to be recognized and symptoms involving numbers are exceptionally rare. We report a patient with hypoxic brain injury following cardiac arrest who showed signs of neglect dyslexia for numbers that provided a primary clue for the diagnosis of left hemispatial neglect. Early detection of different forms of cognitive dysfunction of hypoxic brain injury is highly essential in providing early neurorehabilitation for better prognosis.

Bertolotti’s syndrome (BS) refers to chronic low back pain (LBP) associated with lumbosacral transitional vertebrae (LSTV). Many studies suggest that the anomalous articulation alters biomechanics, resulting in discomfort on the ipsilateral side. Herein, we present an unusual case of BS presenting pain on the non-articulated side. A 46-year-old man visited our clinic with history of chronic LBP, refractory to treatment of analgesics, modalities and manual therapies. Electrodiagnostic studies showed no evidence of lumbosacral radiculopathy. Radiographies noted unilateral pseudoarticulation of L5∼S1 vertebrae, on the contralateral side of his pain. The pain improved dramatically after sacroiliac joint block and facet joint block with iliolumbar ligament infiltration on the non-articulated side. Clinicians should be cautious that the unaffected joint in BS may serve an important role in altered lumbopelvic biomechanism, since it might eventually lead to intractable chronic LBP when overlooked.

Systemic vasculitis is a rare disease, and the diagnosis is very difficult when patient shows atypical symptoms. We experienced an unusual case of dysphagia caused by Churg-Strauss syndrome with lower cranial nerve involvement. A 74-year-old man, with a past history of sinusitis, asthma, and hearing deficiency, was admitted to our department for evaluation of dysphagia. He also complained of recurrent bleeding of nasal cavities and esophagus. Brain magnetic resonance imaging did not show definite abnormality, and electrophysiologic findings were suggestive of mononeuritis multiplex. Dysphagia had not improved after conventional therapy. Biopsy of the nasal cavity showed extravascular eosinophilic infiltration. All these findings suggested a rare form of Churg-Strauss syndrome involving multiple lower cranial nerves. Dysphagia improved after steroid therapy.
Aged ; Asthma ; Biopsy ; Brain ; Churg-Strauss Syndrome* ; Cranial Nerve Diseases ; Cranial Nerves ; Deglutition Disorders* ; Diagnosis ; Eosinophils ; Esophagus ; Hearing ; Hemorrhage ; Humans ; Magnetic Resonance Imaging ; Mononeuropathies ; Nasal Cavity ; Rare Diseases ; Sinusitis ; Systemic Vasculitis

We found that an error in wording in the abstract should be corrected.

We found that an error in wording in the abstract should be corrected.

OBJECTIVE: To evaluate Korean physiatrists' practice of performing intramuscular botulinum toxin injection in anticoagulated patients and to assess their preference in controlling the bleeding risk before injection. METHODS: As part of an international collaboration survey study, a questionnaire survey was administered to 100 Korean physiatrists. Physiatrists were asked about their level of experience with botulinum toxin injection, the safe international normalized ratio range in anticoagulated patients undergoing injection, their tendency for injecting into deep muscles, and their experience of bleeding complications. RESULTS: International normalized ratio <2.0 was perceived as an ideal range for performing Botulinum toxin injection by 41% of the respondents. Thirty-six respondents replied that the international normalized ratio should be lowered to sub-therapeutic levels before injection, and 18% of the respondents reported that anticoagulants should be intentionally withheld and discontinued prior to injection. In addition, 20%-30% of the respondents answered that they were uncertain whether they should perform the injection regardless of the international normalized ratio values. About 69% of the respondents replied that they did have any standardized protocols for performing botulinum toxin injection in patients using anticoagulants. Only 1 physiatrist replied that he had encountered a case of compartment syndrome. CONCLUSION: In accordance with the lack of consensus in performing intramuscular botulinum toxin injection in anticoagulated patients, our survey shows a wide range of practices among many Korean physiatrists; they tend to avoid botulinum toxin injection in anticoagulated patients and are uncertain about how to approach these patients. The results of this study emphasize the need for formulating a proper international consensus on botulinum toxin injection management in anticoagulated patients.
Anticoagulants ; Botulinum Toxins* ; Compartment Syndromes ; Consensus ; Cooperative Behavior ; Surveys and Questionnaires ; Hemorrhage ; Humans ; Injections, Intramuscular* ; Intention ; International Normalized Ratio ; Muscles