Branched-chain amino acids-induced cardiac protection against ischemia/reperfusion injury

Aims: Amino acids, especially branched chain amino acids (BCAAs), have important regulatory roles in protein synthesis. Recently studies revealed that BCAAs protect against ischemia/reperfusion (I/R) injury. We studied the signaling pathway and mitochondrial function affecting a cardiac preconditioning of BCAAs. Main methods: An in vivo model of I/R injury was tested in control, mTOR+/+, and mTOR+/−. Mice were randomly assigned to receive BCAAs, rapamycin, or BCAAs + rapamycin. Furthermore, isolated cardiomyocytes were subjected to simulated ischemia and cell death was quantified. Biochemical and mitochondrial swelling assays were also performed. Key findings: Mice treated with BCAAs had a significant reduction in infarct size as a percentage of the area at risk compared to controls (34.1 ± 3.9% vs. 44.7 ± 2.6%, P = 0.001), whereas mice treated with the mTOR inhibitor rapamycin were not protected by BCAA administration (42.2 ± 6.5%, vs. control, P = 0.015). This protection was not detected in our hetero knockout mice of mTOR. Western blot analysis revealed no change in AKT signaling whereas activation of mTOR was identified. Furthermore, BCAAs prevented swelling which was reversed by the addition of rapamycin. In myocytes undergoing simulated I/R, BCAA treatment significantly preserved cell viability (71.7 ± 2.7% vs. 34.5 ± 1.6%, respectively, p < 0.0001), whereas rapamycin prevented this BCAA-induced cardioprotective effect (43.5 ± 3.4% vs. BCAA, p < 0.0001). Significance: BCAA treatment exhibits a protective effect in myocardial I/R injury and that mTOR plays an important role in this preconditioning effect.This work was supported by JSPS KAKENHI, Japan [grant number 19K09353]

Precise Prediction of Right Atrium Position within Expiratory Phase Thorax

Fifteen patients who underwent CT during both the inspiratory and expiratory phases were retrospectively reviewed. The anterior posterior (AP) diameter of the thorax, the largest vertical distance from the uppermost RA level to the back surface (RA height), and the ratio of RA height to AP diameter of the thorax (RA thorax ratio) were determined. We then attempted to predict the expiratory RA height using the following 2 methods. Formula 1: Predicted expiratory RA height = Average inspiratory RA thorax ratio × Expiratory AP diameter of thorax. Formula 2: Predicted expiratory RA height = Each inspiratory RA thorax ratio × Expiratory AP diameter of thorax. In a Bland-Altman plot with Formula 1, the bias was –0.34 mm and limit of agreement ranged from –19.44 to 18.75 mm, whereas those were –1.31 mm and –9.72 to 7.10 mm with Formula 2. Our findings indicate that inspiratory CT imaging and expiratory phase thorax diameter can be used to precisely predict expiratory phase RA height in individual patients

Evaluation of Hemodynamics During Posture Change to Knee-Chest Position by FloTracTM

In order to evaluate changes in hemodynamics, a FloTracTM system was used during posture change from supine to knee-chest position. Thirty-five patients undergoing lumbar surgery participated in this study. Anesthesia was performed with total intravenous anesthesia using propofol and remifentanil. Cardiac index (CI), stroke volume index (SVI), and stroke volume variation (SVV) were measured by using FloTracTM in addition with heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean blood pressure (MBP). The values before and after postural change were compared. SVV increased immediately after posture change and remained high. With posture change to the knee-chest position, HR, DBP and SVV increased and SBP, CI and SVI decreased. An increase in SVV from immediately after postural change indicated that SVV did not reflect circulating blood volume

Comparison of Prone Position and Knee-Chest Position in Hemodynamics During Postural Change

全静脈麻酔下で腹臥位または膝胸位へ体位変換した際の循環動態を両体位で比較するため，腰部脊椎手術を受けた患者を後方視的に調査した。体位変換の直前，体位変換直後， ３分後， ５分後の心拍数（HR）および収縮期血圧（SBP），拡張期血圧（DBP），平均血圧（MBP）を測定した。各パラメーターを体位変換前の値を基準とし体位変換後の変化率を算出し膝胸位（Knee-chest群）と腹臥位（Prone群）で比較した。統計はt検定を用いた。対象患者はKnee-chest群３０名，Prone群３０名であった。SBPは体位変換直後から５分後までKnee-chest群で有意に低く，MBPは５分後でKnee-chest群で有意に低く，HRは体位変換直後から５分後までKnee-chest群で有意に高かった。このため，全静脈麻酔管理下で膝胸位への体位変換は，腹臥位への体位変換よりも血圧の低下に注意する必要があると結論した。We compared the hemodynamics of posture change under general anesthesia between prone position and knee chest position. Patients who underwent lumbar spinal surgery were retrospectively investigated.　Heart rate (HR) and systolic blood pressure (SBP), diastolic blood pressure (DBP), mean blood pressure (MBP) were measured before and after postural change, 3 minutes and 5 minutes after postural change.　The rate of change of each parameter was calculated and compared in both groups of knee-chest and prone position.　Student’s t-test was used as statistical methods. We analyzed 60 patients (30 Knee-chest, 30 Prone).　SBP was significantly lower in the Knee-chest group from immediately after postural change to 5 minutes after postural change. MBP was significantly lower in the Knee-chest group 5 minutes after postural change. HR was significantly higher in the Knee-chest group from immediately after body change to 5 minutes after postural change.　In conclusion, SBP and MBP were significantly lower in the knee-chest position than in the prone position during postural change. Postural change to the kneechest position requires attention to lowering of blood pressure than postural change to the prone position

A Case of Horner’s Syndrome Caused by Thoracic Epidural Anesthesia

Horner’s syndrome is a syndrome characterized by miosis, eyelid ptosis, narrowing of the eyelids and ocular depression. Diagnosis of the causative disease is important because it may accompany fatal diseases such as brain stem infarction and bleeding, spinal hematoma and neoplastic lesion and internal carotid artery dissection. A woman in her 60s. Left lung lower lobectomy was performed with thoracoscopy assistance for left lung cancer. General anesthesia with epidural anesthesia was performed with propofol and remifentanil. The epidural catheter was punctured from the sixth seventh thoracic vertebrae. Horner’s syndrome occurred on 2 days postoperatively. After reducing epidural anesthesia, symptoms improved. From this, epidural anesthesia proved to be the cause of Horner’s syndrome. Epidural anesthesia can rarely cause Horner’s syndrome

Three Cases Becoming Difficult to Remove Epidural Catheter Postoperatively Due to Coagulation Defect Associated with Antibiotics

Perioperative vitamin K deficiency can cause severe coagulopathy rapidly. Vitamin K deficiency tends to be overlooked despite the elucidation of pathophysiology and countermeasures. The main causes of vitamin K deficiency are insufficient intake, low supply from intestinal bacteria, and synthesis inhibition of vitamin K by N-methyltetrazolethiol (N - MTT) contained antibiotics. We experienced three cases in which it was difficult to remove epidural catheter because of coagulation abnormality due to vitamin K deficiency after surgery. Vitamin K deficiency should be wary of when epidural catheter is indwelled or withdrawn from a patient who is administered with antibiotic containing N-MTT in the fasted state

Plasma levels of matrix metalloproteinase‐9 (MMP‐9) are associated with cognitive performance in patients with schizophrenia

Aim: Matrix metalloproteinase‐9 (MMP‐9) has been shown to modulate synaptic plasticity and may contribute to the pathophysiology of schizophrenia. This study investigated the peripheral levels of MMP‐9 and its association with cognitive functions in patients with schizophrenia to see the possible involvement of MMP‐9 in pathophysiology of schizophrenia, especially in cognitive decline. Methods: We measured the plasma levels of MMP‐9 in 257 healthy controls and 249 patients with schizophrenia, including antipsychotic drug–free patients. We also explored the possible association between plasma MMP‐9 levels and cognitive performance in healthy controls and patients with schizophrenia using the Wechsler Adult Intelligence Scale, Third Edition (WAIS‐ III), the Wechsler Memory Scale‐Revised (WMS‐R), and the Rey Auditory Verbal Learning Test (AVLT). Results: We found that the plasma levels of MMP‐9 were significantly higher in patients with schizophrenia, including antipsychotic drug–free patients, than in healthy controls. We found a significant negative association between plasma MMP‐9 levels and cognitive performance in controls and patients with schizophrenia. Conclusion: Together, these convergent data suggest a possible biological mechanism for schizophrenia, whereby increased MMP‐9 levels are associated with cognitive impairment