Microstripe pattern substrate consisting of alternating planar and nanoprotrusive regions improved hiPSC-derived cardiomyocytes' unidirectional alignment and functional properties.

The alignment of each cell in human myocardium is considered critical for the efficient movement of cardiac tissue. We investigated 96-well microstripe-patterned plates to align human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes (CMs), which resemble fetal myocardium. The aligned CMs (ACMs) cultured on the microstripe-patterned plates exhibited pathology, motor function, gene expression, and drug response that more closely resembled those of adult cells than did unaligned CMs cultured on a flat plate (FCMs). We used these ACMs to evaluate drug side effects and efficacy, and to determine whether these were similar to adult-like responses. When CMs from patients with hypertrophic cardiomyopathy (HCMs) were seeded and cultured on the microstripe-patterned plates or layered on top of the ACMs, both sets of HCMs showed increased heart rate and synchronized contractions, indicating improved cardiac function. It is suggested that the ACMs could be used for drug screening as cells representative of adult-like CMs and be transplanted in the form of a cell sheet for regenerative treatment of heart failure.

A Case of Nasal Mucosa Cautery With Reintubation Under Pharyngeal Suction for Massive Epistaxis After Extubation.

We describe a case of massive epistaxis that occurred after removal of a nasal endotracheal tube, prompting emergent reintubation. Mask ventilation could not be performed because the nasal cavity was packed with gauze and the airway was being evacuated with a suction catheter. Therefore, instead of inhalational anesthetics and muscle relaxants, boluses of midazolam and remifentanil were administered, and reintubation was promptly performed. Sedation was maintained with dexmedetomidine infusion and midazolam. Nasal cautery was performed near the left sphenopalatine foramen. The patient was extubated without agitation or additional hemorrhage. Immediate recognition of the potential for airway loss, sufficient control of active bleeding, and drug selection in accordance with the emergent circumstances enabled prompt resecuring of the airway without pulmonary aspiration of blood.

Utility of High-Intensity Laser Therapy Combined with Photobiomodulation Therapy for Socket Preservation After Tooth Extraction.

Objective: High-intensity laser therapy (HILT) combined with photobiomodulation therapy (PBMT) using a diode or CO2 laser was administered after extraction of the left first molar in rats. Effects on socket preservation (preservation of the alveolar bone and healing time after extraction) were evaluated histopathologically. Background: Irradiation using a diode or CO2 laser has been shown to hasten wound healing, but the effects remain controversial. Methods: Five-week-old male Wistar rats that underwent extraction of the left maxillary first molar were divided into three groups: diode laser irradiation (diode group), CO2 laser irradiation (CO2 group), and no laser irradiation (control group). HILT (27 J) was performed immediately after tooth extraction to enhance blood coagulation, followed by PBMT (0.7 J) 1 day later to enhance healing. Tissues, including the extraction socket, were removed en bloc 3, 5, 7, 10, and 21 days postextraction to determine the morphological characteristics of wound healing and the distribution of myofibroblasts involved in scar formation. Results: In the diode and CO2 groups, new bone formation and cancellous bone maturation were observed at an early stage of wound healing. The number of myofibroblasts was significantly lower in the laser treatment groups than the control (p < 0.001), and both treatment groups had a significantly higher alveolar crest height (p < 0.01), with almost no concavity in the mucosa of the extraction wound. Conclusions: Combined HILT and PBMT following tooth extraction hastened wound healing and preserved alveolar crest height, suggesting a role in socket preservation.

A Case of Cardiac Arrest for 31 Seconds During Recovery After Intravenous Sedation.

A 26-year-old woman with a history of feeling nauseated during dental local anesthesia presented to our clinic for tooth extraction under intravenous sedation. Although she had experienced episodes of neurally-mediated syncope, her symptoms were controlled well with drug therapy, stopped 3 years earlier. No syncope episodes developed over the previous 2 years. Tooth extraction was performed under intravenous sedation without incident. When she was returned to a sitting position after being roused, convulsion, loss of consciousness, and cardiac arrest developed. One week later, similar symptoms occurred immediately after suture removal. We suspect that the change in body position triggered these episodes. It is important to avoid abrupt changes in body position and any other triggers and to administer preventive drugs in patients at high risk of syncope.

Recurrent Coronary Artery Spasm Induced by Vasopressors During Two Operations in the Same Patient Under General Anesthesia.

Variant angina is caused by coronary artery spasm (CAS) with ST-segment elevation. We herein report a case of recurrent CAS during 2 operations in the same patient. An 80-year-old woman was scheduled to undergo tracheostomy, submandibular dissection, left partial maxillectomy, and coronoidectomy. We administered ephedrine and phenylephrine to manage hypotension during general anesthesia. Immediately after the administration of these drugs, the ST segment elevated. We decided to cease the operation and transport the patient to the department of cardiology. Computed tomography angiography revealed pneumomediastinum. The cardiologists considered that the electrocardiography findings had changed secondary to pneumomediastinum. About 6 weeks later, a second operation was scheduled. We administered ephedrine and phenylephrine to manage hypotension during general anesthesia. Immediately after the administration of these drugs, ST-segment elevation occurred. We discontinued use of these drugs, and the ST-segment elevation did not recur. We considered that the cause of the ST-segment elevation was vasopressor-induced CAS because the vasopressors were administered immediately before the occurrence of CAS. Vasopressors such as ephedrine or phenylephrine are frequently used to manage hypotension during general anesthesia. Therefore, anesthesiologists should consider the occurrence of CAS before using vasopressors and know how to manage CAS well.