RAD52-mediated repair of DNA double-stranded breaks at inactive centromeres leads to subsequent apoptotic cell death.

Centromeres, where the kinetochore complex binds, are susceptible to damages including DNA double-stranded breaks (DSBs). Here, we report the functional significance and the temporally and spatially distinct regulation of centromeric DSB repair via the three pathways of non-homologous end joining (NHEJ), homologous recombination (HR) and single-strand annealing (SSA). The SSA factor RAD52 is most frequently recruited to centromeric DSB sites compared with the HR factor RAD51 and the NHEJ factor DNA ligase IV (LIG4), indicating that SSA plays predominant roles in centromeric DSB repair. Upon centromeric DSB induction, LIG4 is recruited to both active centromeres, where kinetochore complex binds, and inactive centromeres. In contrast, RAD51 and RAD52 are recruited only to inactive centromeres. These results indicate that DSBs at active centromeres are repaired through NHEJ, whereas the three pathways of NHEJ, HR and SSA are involved in DSB repair at inactive centromeres. Furthermore, siRNA-mediated depletion of either LIG4 or RAD51 promotes cell death after centromeric DSB induction, whereas RAD52 depletion inhibits it, suggesting that HR and NHEJ are required for appropriate centromeric DSB repair, whereas SSA-mediated centromeric DSB repair leads to subsequent cell death. Thus, SSA-mediated DSB repair at inactive centromeres may cause centromere dysfunction through error-prone repair.

Effects of palliative intrathecal analgesia on patients with refractory cancer bone pain.

This study examined the effects of intrathecal analgesia (ITA) using an extracorporeal pump with a subcutaneous port system in cancer patients with bone metastasis. Among the patients who died of cancer with bone metastasis at the palliative care unit of our institution, 11 who received ITA were selected. Changes in pain, opioid doses, the palliative prognostic index (PPI), and Eastern Cooperative Oncology Group Performance Scale　after ITA were assessed. Pain, opioid doses, and PPI decreased after ITA (P = 0.002, 0.002, and 0.017). ITA for cancer patients with increased PPI due to refractory cancer bone pain decreased pain, opioid doses, and PPI.(100 words).

Detection of carbon dioxide embolism by transesophageal echocardiography during transanal/perineal endoscopic surgery: a pilot study.

The transanal/perineal (ta/tp) endoscopic approach has been widely used for anorectal surgery in recent years, but carbon dioxide embolism is a possible lethal complication. The frequency of this complication in this approach is not known. In this study, we investigated the frequency of intraoperative (including occult) carbon dioxide embolism using transesophageal echocardiography. Patients who underwent surgery via the ta/tp approach and consented to participate were included. Intraoperative transesophageal echocardiography was used to observe the right ventricular system in a four-chamber view. Changes in end-tidal carbon dioxide (EtCO2), oxygen saturation (SpO2), and blood pressure were taken from anesthesia records. Median maximum insufflation pressure during the ta/tp approach was 13.5 (12-18) mmHg. One patient (4.8%) was observed to have a bubble in the right atrium on intraoperative transesophageal echocardiography, with a decrease in EtCO2 from 39 to 35 mmHg but no obvious change in SpO2 or blood pressure. By lowering the insufflation pressure from 15 to 10 mmHg and controlling bleeding from the veins around the prostate, the gas rapidly disappeared and the operation could be continued. Among all patients, the range of variation in intraoperative EtCO2 was 5-22 mmHg, and an intraoperative decrease in EtCO2 of > 3 mmHg within 5 min was observed in 19 patients (median 5 mmHg in 1-10 times).Clinicians should be aware of carbon dioxide embolism as a rare but potentially lethal complication of anorectal surgery, especially when using the ta/tp approach.

Cerebral hemorrhagic infarction was diagnosed subsequently after high-amplitude slow waves detected on processed electroencephalogram during sedation: a case report.

BACKGROUND: Continuous electroencephalogram (EEG) monitoring is useful for assessing the level of sedation and detecting non-convulsive epileptic seizures and cerebral ischemia in the intensive care unit. This report describes a case of cerebral hemorrhagic infarction diagnosed after the detection of high-amplitude slow waves on processed EEG during sedation. CASE PRESENTATION: A 68-year-old man who underwent cardiac surgery was sedated in the intensive care unit following an invasive procedure. High-amplitude slow waves appeared on processed EEG monitoring before the detection of anisocoria. Computed tomography revealed a cerebral hemorrhagic infarction. CONCLUSIONS: In the management of critically ill patients, continuous EEG monitoring with forehead electrodes may be useful in the early detection of brain lesions.

Comparison of Body Mass Index and Waist Circumference in the Prediction of Diabetes: A Retrospective Longitudinal Study.

INTRODUCTION: Both body mass index (BMI) and waist circumference (WC) are associated with diabetes risk, and the difference between them in predictive ability for diabetes is still contentious. We conducted a population-based study to investigate and compare the association of them with diabetes by sex. METHODS: This study included a total of 4754 subjects aged 40-80 years with no diabetes at baseline between 2008 and 2017. Using multivariate Cox proportional hazards models, we calculated hazard ratios for diabetes according to tertiles of BMI or WC. Harrell's C statistics was applied to assess and compare the predictive ability of the models using BMI and WC. RESULTS: Both BMI and WC showed the significant positive trends with diabetes risk. In men, the extreme tertiles (BMI > 25.1 kg/m2 and WC > 88.0 cm) provided 1.58-fold or 2.04-fold higher risk compared with the first tertiles (< 22.6 kg/m2 and < 81.2 cm). In women, BMI > 24.4 kg/m2 showed 3.28-fold higher risk than the first tertile (< 21.6 kg/m2), whereas WC ≥ 78.2 cm was more than twice as likely to suffer from diabetes as WC < 78.2 cm. BMI and WC showed a comparative performance in predicting diabetes in both sexes (P value 0.447 in men, and 0.337 in women). CONCLUSION: Both BMI and WC showed a positive association with diabetes and offered a comparative predictive performance for diabetes in both sexes. The cut-off points, BMI 25.1 kg/m2 and WC 88.0 cm in men and BMI 24.4 kg/m2 and WC 78.2 cm in women, might contribute to the effective prevention strategies for diabetes.

Effect of face shield design on the prevention of sneeze droplet inhalation.

A flow simulation was performed for face shields to investigate whether varying a shield's edge shape could prevent droplets from entering the shield. Face shields with two types of edge shapes were used. The "Type I" shield had small plates mounted on the top and bottom edges of the shield to physically inhibit the sneeze inflow. The "Type II" shield had small brims sticking forward from the shield surface and small plates sticking upward and downward at the top and bottom edges to inhibit the entrainment flow produced by the vortex ring using sneeze flow. We confirmed that the flow characteristics around a face shield can be controlled using the shield's edge shape. In Type I, the entraining flow inside the shield was inhibited by the mounted small plate at the bottom edge, ensuring the inhibiting effect, but not at the top edge. In Type II, the entrained flow inside the shield was inhibited by the mounted brim and small plate at the top edge, ensuring the inhibiting effect, but not at the bottom edge. The effects of the Type II design parameters on the flow characteristics around the face shield were examined. The results indicate that at the top edge, increasing the length of the brim and not mounting the small plate at an incline from the shield surface improves the inhibition effect. At the bottom edge, shortening the length of the brim and mounting the small plate at an incline from the shield surface improves the inhibition effect.

Effect of sneezing on the flow around a face shield.

A flow analysis around a face shield was performed to examine the risk of virus infection when a medical worker wearing a face shield is exposed to a patient's sneeze from the front. We ensured a space between the shield surface and the face of the human model to imitate the most popularly used face shields. In the present simulation, a large eddy simulation was conducted to simulate the vortex structure generated by the sneezing flow near the face shield. It was confirmed that the airflow in the space between the face shield and the face was observed to vary with human respiration. The high-velocity flow created by sneezing or coughing generates vortex ring structures, which gradually become unstable and deform in three dimensions. Vortex rings reach the top and bottom edges of the shield and form a high-velocity entrainment flow. It is suggested that vortex rings capture small-sized particles, i.e., sneezing droplets and aerosols, and transport them to the top and bottom edges of the face shield because vortex rings have the ability to transport microparticles. It was also confirmed that some particles (in this simulation, 4.4% of the released droplets) entered the inside of the face shield and reached the vicinity of the nose. This indicates that a medical worker wearing a face shield may inhale the transported droplets or aerosol if the time when the vortex rings reach the face shield is synchronized with the inhalation period of breathing.

Esophageal Submucosal Hematoma Possibly Caused by Gastric Tube Insertion Under General Anesthesia.

We present a case of an esophageal submucosal hematoma that developed after endovascular treatment for coil embolization for an unruptured cerebral aneurysm. The patient had received antiplatelet therapy before surgery and anticoagulation therapy during surgery. The orogastric tube was removed at case end with sustained negative pressure. After surgery, the patient reported chest and back pain and was diagnosed with an esophageal submucosal hematoma. The hematoma might have been related to the gastric tube insertion or removal. Providers should keep in mind the possibility of this complication when a patient who was given antithrombotic therapy reports chest or back pain after surgery.

Differences in anatomical relationship between vertebral artery and internal jugular vein in children and adults measured by ultrasonography.

Cannulation of the internal jugular vein (IJV) under ultrasound guidance can reduce complications, such as common carotid artery (CCA) puncture, accidental vertebral artery (VA) puncture. However, these complications still occur, especially in pediatric patients probably due to anatomical predisposition of VA. This study compared differences in anatomical location of VA and IJV between pediatric and adult patients. Children with body weight <20 kg (n = 16) and adults who required central venous or pulmonary arterial pressure monitoring (n = 21) were enrolled. After induction of general anesthesia and tracheal intubation, patients were positioned for IJV cannulation. Images of the right CCA, IJV and VA were recorded by ultrasonography. The size of each vessel, anatomical relationship of other vessels, distance between vessels and between each vessel and skin were measured. The size of VA relative to IJV was significantly larger in children than in adults (14 vs 7 %, P < 0.001). The absolute and relative distance between IJV and VA were significantly shorter in children than those in adults (P < 0.01). The anatomical relationships between IJV and CCA and that between IJV and VA were not different between children and adults. In children, VA was relatively larger and located closer to IJV than adults. The results call for careful attention to the position of VA during ultrasound-guided IJV cannulation especially in children.

Myelin specific cells infiltrate MCAO lesions and exacerbate stroke severity.

Although inflammatory responses increase stroke severity, the role of immune cells specific for central nervous system (CNS) antigens remains controversial. Disruption of the blood-brain barrier (BBB) during stroke allows CNS antigens to leak into the peripheral circulation and enhances access of circulating leukocytes to the brain, including those specific for CNS antigens such as myelin oligodendrocyte glycoprotein (MOG) that can induce experimental autoimmune encephalomyelitis (EAE). We here demonstrate for the first time that myelin reactive splenocytes specific for MOG transferred into severe combined immunodeficient (SCID) mice can migrate into the infarct hemisphere of recipients subjected to 60 min middle cerebral artery occlusion (MCAO) and 96 h reperfusion; moreover these cells exacerbate infarct volume and worsen neurological deficits compared to animals transferred with naïve splenocytes. These findings indicate that autoimmunity in the CNS can exert detrimental injury on brain cells and worsen the damage from ischemic stroke.

Recombinant T cell receptor ligands improve outcome after experimental cerebral ischemia.

A key target for novel stroke therapy is the regulation of post-ischemic inflammatory mechanisms. Recent evidence emphasizes the role of T lymphocytes of differing subtypes in the evolution is ischemic brain damage. We have recently demonstrated the benefit of myelin antigen-specific immunodulatory agents known as recombinant T cell receptor ligands (RTLs) in a standard murine model of focal stroke. The aim of the current study was to extend this initial observation to RTL treatment in a therapeutically relevant timing after middle cerebral artery occlusion (MCAO) and verify functional benefit to complement histological outcome measures. We observed that the administration of mouse-specific RTL551 reduced infarct size and improved sensorimotor outcome when administered within a 3 h post-ischemic therapeutic window. RTL551 treatment reduced cortical, caudate putamen, and total infarct volume as compared to vehicle-treated mice. Using a standard behavioral testing repertoire, we observed that RTL551 reduced sensorimotor impairment 3 days after MCAO. Humanized RTL1000 (HLA-DR2 moiety linked to hMOG-35-55 peptide) also reduced infarct size in HLA-DR2 transgenic mice. These data indicate that this neuroantigen-specific immunomodulatory agent reduces damage when administered in a therapeutically relevant reperfusion timeframe.

Programmed death-1 pathway limits central nervous system inflammation and neurologic deficits in murine experimental stroke.

BACKGROUND AND PURPOSE: Evaluation of infarct volumes and infiltrating immune cell populations in mice after middle cerebral artery occlusion strongly implicates a mixture of both pathogenic and regulatory immune cell subsets that affect stroke outcome. Our goal was to evaluate the contribution of the well-described coinhibitory pathway, programmed death (PD)-1, to the development of middle cerebral artery occlusion. METHODS: Infarct volumes, functional outcomes, and effects on infiltrating immune cell populations were compared in wild-type C57BL/6 versus PD-1-deficient mice after 60 minutes middle cerebral artery occlusion and 96 hours reperfusion. RESULTS: The results clearly demonstrate a previously unrecognized activity of the PD-1 pathway to limit infarct volume, recruitment of inflammatory cells from the periphery, activation of macrophages and central nervous system microglia, and functional neurological deficits. These regulatory functions were associated with increased percentages of circulating PD-ligand-1 and PD-ligand-2 expressing CD19(+) B-cells in blood, the spleen, and central nervous system with the capacity to inhibit activation of inflammatory T-cells and central nervous system macrophages and microglial cells through upregulated PD-1. CONCLUSIONS: Our novel observations are the first to implicate PD-1 signaling as a major protective pathway for limiting central nervous system inflammation in middle cerebral artery occlusion. This inhibitory circuit would likely be pivotal in reducing stroke-associated Toll-like receptor-2- and Toll like receptor-4-mediated release of neurotoxic factors by activated central nervous system microglia.

Regulatory B cells limit CNS inflammation and neurologic deficits in murine experimental stroke.

Evaluation of infarct volumes and infiltrating immune cell populations in mice after middle cerebral artery occlusion (MCAO) strongly implicates a mixture of both pathogenic and regulatory immune cell subsets in stroke pathogenesis and recovery. Our goal was to evaluate the contribution of B cells to the development of MCAO by comparing infarct volumes and functional outcomes in wild-type (WT) versus B-cell-deficient µMT(-/-) mice. The results clearly demonstrate larger infarct volumes, higher mortality, more severe functional deficits, and increased numbers of activated T cells, macrophages, microglial cells, and neutrophils in the affected brain hemisphere of MCAO-treated µMT(-/-) versus WT mice. These MCAO-induced changes were completely prevented in B-cell-restored µMT(-/-) mice after transfer of highly purified WT GFP(+) B cells that were detected in the periphery, but not the CNS. In contrast, transfer of B cells from IL-10(-/-) mice had no effect on infarct volume when transferred into µMT(-/-) mice. These findings strongly support a previously unrecognized activity of IL-10-secreting WT B cells to limit infarct volume, mortality rate, recruitment of inflammatory cells, and functional neurological deficits 48 h after MCAO. Our novel observations are the first to implicate IL-10-secreting B cells as a major regulatory cell type in stroke and suggest that enhancement of regulatory B cells might have application as a novel therapy for this devastating neurologic condition.

Therapy with recombinant T-cell receptor ligand reduces infarct size and infiltrating inflammatory cells in brain after middle cerebral artery occlusion in mice.

Stroke induces a biphasic effect on the peripheral immune response that involves early activation of peripheral leukocytes followed by severe immunosuppression and atrophy of the spleen. Peripheral immune cells, including T lymphocytes, migrate to the brain and exacerbate the developing infarct. Recombinant T-cell receptor (TCR) Ligand (RTL)551 is designed as a partial TCR agonist for myelin oligodendrocyte glycoprotein (MOG)-reactive T cells and has demonstrated the capacity to limit infarct volume and inflammation in brain when administered to mice undergoing middle cerebral artery occlusion (MCAO). The goal of this study was to determine if RTL551 could retain protection when given within the therapeutically relevant 4 h time window currently in clinical practice for stroke patients. RTL551 was administered subcutaneously 4 h after MCAO, with repeated doses every 24 h until the time of euthanasia. Cell numbers were assessed in the brain, blood, spleen and lymph nodes and infarct size was measured after 24 and 96 h reperfusion. RTL551 reduced infarct size in both cortex and striatum at 24 h and in cortex at 96 h after MCAO and inhibited the accumulation of inflammatory cells in brain at both time points. At 24 h post-MCAO, RTL551 reduced the frequency of the activation marker, CD44, on T-cells in blood and in the ischemic hemisphere. Moreover, RTL551 reduced expression of the chemokine receptors, CCR5 in lymph nodes and spleen, and CCR7 in the blood and lymph nodes. These data demonstrate effective treatment of experimental stroke with RTL551 within a therapeutically relevant 4 h time window through immune regulation of myelin-reactive inflammatory T-cells.

Accuracy of arterial pressure waveform analysis for cardiac output measurement in comparison with thermodilution methods in patients undergoing living donor liver transplantation.

PURPOSE: The aim of this study was to assess the accuracy of the first and third versions of arterial pressure waveform cardiac output (APCO(v.1.0) and APCO(v.3.0)) measurements in comparison with thermodilution methods in patients undergoing living donor liver transplantation. METHODS: Twenty patients were anesthetized and mechanically ventilated. A radial arterial line was connected to a dedicated transducer for the APCO evaluation (FloTrac™). A pulmonary artery catheter was placed and connected to a computer system (Vigilance™) to measure intermittent thermodilution cardiac output (CO(TD)) and continuous cardiac output (CCO). RESULTS: A total of 138 measurements were analyzed. Bland-Altman analysis showed that the mean biases for CO(TD)-APCO(v.3.0), CO(TD)-APCO(v.1.0), and CO(TD)-CCO were 0.89, 1.73, and -0.79 L/min, and the adjusted percentage errors were 37.5, 30.3, and 43%, respectively. While the variance for CO(TD)-APCO(v3.0) was greater, the accuracy (bias) improved by 0.8 L/min as compared with CO(TD)-APCO(v1.0). The difference CO(TD)-APCO(v.3.0) became apparent when systemic vascular resistance was lower than 1000 dyne × s/cm(5), especially below 700 dyne × s/cm(5). CONCLUSION: These data suggest that the accuracy of APCO(v.3.0) has improved compared to APCO(v.1.0) due to the updated algorithm, but additional improvements should be evaluated, especially in patients undergoing living donor liver transplantation with low systemic vascular resistance.

Role of dihydrotestosterone in post-stroke peripheral immunosuppression after cerebral ischemia.

Stroke is a sexually dimorphic disease with male gender considered a disadvantage in terms of risk and disease outcome. In intact males, stroke induces peripheral immunosuppression, characterized by decreased splenocyte numbers and proliferation and altered percentages of viable T, B, and CD11b+ cells. To investigate whether the potent androgen and known immunomodulator, dihydrotestosterone (DHT), exacerbates post-stroke immunosuppression in castrated male mice after focal stroke, we evaluated the effect of middle cerebral artery occlusion (MCAO) on peripheral and central nervous system (CNS) immune responses in castrated mice with or without controlled levels of DHT. MCAO reduced spleen cell numbers in both groups, but altered T cell and B cell percentages in remaining splenocytes and concomitantly increased the percentage of CD11b+ blood cells solely in DHT-replaced animals at 24 h. Furthermore, DHT-replacement reduced splenocyte proliferation which was accompanied by an increased percentage of immunosuppressive regulatory T cells relative to castrates 96 h post-MCAO. In brain, the percentages of immune cell populations in the ischemic hemisphere relative to the non-ischemic hemisphere were similar between castrated and DHT-replaced mice after MCAO. These data suggest DHT modulates peripheral immunosuppression after MCAO but with relatively little effect on early immune response of the recovering CNS.

CD4+FoxP3+ regulatory T-cells in cerebral ischemic stroke.

Experimental cerebral ischemic stroke is exacerbated by inflammatory T-cells and is accompanied by systemic increases in CD4+CD25+Foxp3+ regulatory T-cells (Treg). To determine their effect on ischemic brain injury, Treg were depleted in Foxp3(DTR) mice prior to stroke induction. In contrast to a recent Nature Medicine report, our results demonstrate unequivocally that Treg depletion did not affect stroke infarct volume, thus failing to implicate this regulatory pathway in limiting stroke damage.

Androgen receptor overexpression is neuroprotective in experimental stroke.

Male sex is a known risk factor in human stroke. However, the role of the cognate receptor for androgens-the androgen receptor (AR)-in stroke outcome remains unclear. Here, we found that AR mRNA is downregulated in the peri-infarct tissue of gonadally intact male mice subjected to middle cerebral artery occlusion (MCAO) and 6 h reperfusion. We then used genetically engineered mice overexpressing AR in brain (AR-Tg) to compare outcomes from MCAO in intact or castrated males and to evaluate the neuroprotective role of dihydrotestosterone (DHT) replacement in AR-Tg castrates. A further evaluation of AR overexpression in ischemic paradigms was performed using rat PC12 cells transfected with human AR and treated with oxidative and apoptotic stressors. We then studied the role of DHT in cultures overexpressing AR. Our results show (1) ischemia alters the expression of AR by decreasing AR mRNA levels, (2) AR overexpression is protective in vivo against MCAO in intact and castrated AR-Tg mice and in vitro against oxidative and apoptotic stressors in AR-PC12 cells, and (3) DHT does not enhance the protection triggered by AR overexpression in AR-Tg castrated mice nor in AR-PC12 cells.

Estradiol and G1 reduce infarct size and improve immunosuppression after experimental stroke.

Reduced risk and severity of stroke in adult females is thought to depend on normal endogenous levels of estrogen, a well-known neuroprotectant and immunomodulator. In male mice, experimental stroke induces immunosuppression of the peripheral immune system, characterized by a reduction in spleen size and cell numbers and decreased cytokine and chemokine expression. However, stroke-induced immunosuppression has not been evaluated in female mice. To test the hypothesis that estradiol (E2) deficiency exacerbates immunosuppression after focal stroke in females, we evaluated the effect of middle cerebral artery occlusion on infarct size and peripheral and CNS immune responses in ovariectomized mice with or without sustained, controlled levels of 17-beta-E2 administered by s.c. implant or the putative membrane estrogen receptor agonist, G1. Both E2- and G1-replacement decreased infarct volume and partially restored splenocyte numbers. Moreover, E2-replacement increased splenocyte proliferation in response to stimulation with anti-CD3/CD28 Abs and normalized aberrant mRNA expression for cytokines, chemokines, and chemokine receptors and percentage of CD4(+)CD25(+)FoxP3(+) T regulatory cells observed in E2-deficient animals. These beneficial changes in peripheral immunity after E2 replacement were accompanied by a profound reduction in expression of the chemokine, MIP-2, and a 40-fold increased expression of CCR7 in the lesioned brain hemisphere. These results demonstrate for the first time that E2 replacement in ovariectomized female mice improves stroke-induced peripheral immunosuppression.

Performance evaluation of a new pulse oximeter during mild hypothermic cardiopulmonary bypass.

UNLABELLED: Newly developed pulse oximeters (POs) are designed to display accurate SpO(2) during motion and hypoperfusion. We compared the performance of a new PO, the Masimo SET Radical (M), with a conventional PO, the Nihon Kohden AY-900P (N), during hypothermic cardiopulmonary bypass. Eighteen patients were studied prospectively. PO failure was defined as failure to show no SpO(2) value or show incorrect SpO(2) values for longer than 3 min continuously. PO failure occurred in 4 and 14 patients with M and N, respectively (P = 0.0022). All 4 patients in whom PO failure developed with M were among the 14 patients with N. No SpO(2) was provided for 4% +/- 12% of the duration of aorta cross-clamping with M and 36% +/- 39% with N (P = 0.002). Skin temperature and mean arterial blood pressure when PO failure started to occur and ended were similar between M and N. PO failure easily developed in patients with preoperative diuretic therapy or with intraoperative hyperlactatemia in N, but not in M. M was able to display accurate SpO(2) values significantly more frequently and longer than N during mild hypothermic cardiopulmonary bypass with nonpulsatile flow, suggesting that M is more useful for monitoring SpO(2) during hypoperfusion. IMPLICATIONS: We compared the performance of a new pulse oximeter with that of a conventional pulse oximeter during hypothermic cardiopulmonary bypass with nonpulsatile flow. The newly developed device displayed accurate SpO(2) significantly more frequently and longer than a conventional oximeter. Newly developed pulse oximeters seem to be more useful for monitoring SpO(2) during hypoperfusion.