[A case of high cervical cord infarction presenting with cardiopulmonary arrest due to respiratory dysfunction].

A 46-year-old man with neck pain and impaired physical mobility called for emergency medical services. The patient was able to communicate with the emergency medical team upon their arrival. However, he went into cardiopulmonary arrest 5 minutes later. Cardiopulmonary resuscitation was immediately performed, and the patient was admitted to our hospital with a Glasgow Coma Scale score of E1V1M1. His respiratory rate was 5 breaths/minute and his partial pressure of carbon dioxide in arterial blood (PaCO2) was 127 |mmHg, necessitating intubation and ventilation. His consciousness improved as the PaCO2 level decreased. However, he was unable to be weaned off the ventilator and breathe independently. Neurological examination revealed flaccid quadriplegia, pain sensation up to the C5 level, absence of deep tendon reflexes, indifferent plantar responses, and absence of the rectoanal inhibitory reflex. Magnetic resonance imaging showed a hyperintense lesion with slight enlargement of the anterior two-thirds of the spinal cord at the C2-C4 level on both T2-weighted and diffusion-weighted images, consistent with a diagnosis of spinal cord infarction. Although the quadriplegia and sensory loss partially improved, the patient was unable to be weaned from the ventilator. Cervical cord infarction of the anterior spinal artery can cause rapid respiratory failure leading to cardiopulmonary arrest. Therefore, cervical cord infarction should be included as a differential diagnosis when examining patients after cardiopulmonary resuscitation.

One-year morbidity and mortality in patients treated with standard-dose and low-dose apixaban after acute large vessel occlusion stroke.

Although low-dose direct oral anticoagulants (DOACs) are recommended for patients at high risk of bleeding complications, it remains unclear whether the dose reduction in real-world setting is also appropriate in patients after large-vessel occlusion (LVO) stroke. This study hypothesized that patients with atrial fibrillation (AF) and LVO receiving low-dose DOACs have an increased risk of ischemic and hemorrhagic events. The study aimed to assess 1 year morbidity and mortality in patients treated with standard-dose and low-dose apixaban after LVO stroke. A post hoc analysis was performed using the acute LVO registry data, which enrolled patients with AF and LVO who received apixaban within 14 days of stroke onset. The incidences of ischemic events (ischemic stroke, acute coronary syndrome, acute myocardial infarction, and systemic embolism), major bleeding events, and death from any cause were compared between patients receiving standard- and low-dose apixaban. Of 643 patients diagnosed with LVO, 307 (47.7%) received low-dose apixaban. After adjustment for clinically relevant variables, no significant differences were observed in the incidence of ischemic events (adjusted hazard ratio [aHR]: 2.12, 95% confidence interval [CI] 0.75-6.02), major bleeding events (aHR: 1.17, 95% CI 0.50-2.73), and death from any cause (aHR: 1.95, 95% CI 0.78-4.89) between patients receiving standard- and low-dose apixaban. No significant differences were observed in the incidence of ischemic events, major bleeding events, or death from any cause between patients with AF and LVO receiving standard- and low-dose apixaban.

Case report: Usefulness of angioscopy in determining antiplatelet drug reduction after carotid artery stenting.

We report a case in which neointima was confirmed by angioscopy and antiplatelet drug administration was reduced 2 months after carotid artery stenting (CAS). A patient in their 80s was scheduled to undergo resection for renal cancer; however, he also had right cervical internal carotid artery stenosis. Because this was a risk for general anesthesia, CAS was performed after first starting dual antiplatelet therapy. Urologically, early reduction of antiplatelet drugs was necessary for a nephrectomy. Although no obvious neointima could be identified on ultrasound 2 months after CAS, thin neointima was observed using angioscopy. Based on the above results, we reduced the antiplatelet drug administration, and then the nephrectomy was performed. Ultimately, no cerebral infarction occurred in the perioperative or postoperative periods. Angioscopy allows for visual confirmation of thin neointima. If sufficient neointima can be confirmed, antiplatelet drug reduction can be performed more safely and reliably.

Intensity-dependent Temperature Rise Induced by Local Exposure to 26.5 GHz Quasi-Millimeter-Wave in Rat.

BACKGROUND/AIM: The widespread use of fifth-generation 5G millimeter-waves (MMW) generates concern about potential adverse health effects. The latest international guidelines for MMW exposure adopt an absorbed power density (APD) of 200 W/m2 to avoid a local temperature rise of 5°C in human tissues as an operational adverse health effect threshold. However, because APD is estimated by simulations using human tissue models, it is unknown whether a similar value can be confirmed for living tissues. The aim of this study was to investigate the relationship between APD and skin temperature rise in vivo, and to validate the estimated values. MATERIALS AND METHODS: The rat dorsal skin was locally exposed to a 26.5 GHz quasi-MMW (qMMW) for 18 min using a patch antenna. The qMMW exposure intensities estimated by dosimetry were set to 0-500 W/m2 of APD. The temperatures in the dorsal skin and rectum were simultaneously measured during exposure. RESULTS: The qMMW-induced local temperature increase at different sites. The dorsal skin temperature increased by approximately 11.3°C at a maximum intensity of 500 W/m2, but the rectal temperature increased by only 0.6°C, indicating highly localized effects of exposure to rats. A significant correlation was observed between APD and skin temperature rise. The relationship provided a linear regression model, and a temperature rise of less than 5°C was estimated in the skin exposed to 200 W/m2 of APD. CONCLUSION: These results suggest that the operational threshold for the MMW exposure guidelines is valid under the present experimental conditions using rats.

Ischemic Stroke Due to Heparin-induced Thrombocytopenia during Severe COVID-19 Infection.

A 53-year-old woman with severe coronavirus disease 2019 (COVID-19) pneumonia was admitted and treated with intravenous unfractionated heparin for thromboprophylaxis under general anesthesia with mechanical ventilation. She developed right hemiparesis after hospitalization due to a large hemorrhagic infarction. Her platelet count decreased from 243,000/µL at administration to 121,000/µL. Anti-platelet factor 4-heparin antibody testing was positive according to a latex immunoturbidimetric assay. She was therefore diagnosed with heparin-induced thrombocytopenia. We immediately stopped the heparin and started argatroban; the platelet count recovered, and thrombosis did not relapse. Physicians should consider heparin-induced thrombocytopenia as a cause of ischemic stroke in patients with COVID-19 infection.

Clinical Impact of Large Vessel Occlusion Achieved First Pass Effect with Stent Retriever Alone: A Single-Center Retrospective Analysis.

Objective: The first pass effect (FPE), which means the achievement of complete or near-complete reperfusion of large vessel occlusion (LVO) in the first pass, is one of the goals of mechanical thrombectomy (MT). However, the impact of FPE on the prognosis has not been assessed for Japanese patients with various degrees of independence before the onset of LVO. The purpose of this study was to investigate the prognostic effects of FPE in a comprehensive stroke center in Japan, which includes patients in a variety of self-independence states with different comorbidities before stroke onset. Methods: Between April 2017 and March 2020, 151 patients who underwent MT with a stent retriever (SR) alone as initial strategy for anterior circulation (internal carotid artery terminal, M1, M2) LVO at our hospital and finally achieved modified treatment in cerebral infarction (mTICI) 2b-3 were analyzed. Forty-eight patients in whom first pass mTICI 2c-3 was achieved were classified into the FPE+ group, and the other 103 patients were classified into the FPE- group. We compared the characteristics and clinical outcomes between patients with and without FPE, and estimated the odds ratio for outcomes after adjusting for confounders. Results: The puncture-reperfusion time was shorter (20 vs. 35 minutes; p <0.01), and cardiogenic embolism was more common (81.3 vs. 60.2%; p = 0.01) in the FPE+ group. The FPE was significantly associated with good neurological outcome after 3 months (p <0.01; adjusted odds ratio [aOR], 3.87; 95% confidence interval [CI], 1.69-9.38), reduction in all intracranial hemorrhage (p <0.01; aOR, 0.24; 95% CI, 0.10-0.54), and symptomatic intracranial hemorrhage (p = 0.04; aOR, 0.16; 95% CI, 0.01-0.98). Conclusion: The FPE with an SR alone improved the neurological prognosis in a Japanese patient group.

Serial Radiological Findings in Meningovascular Neurosyphilis Presenting as Acute Ischemic Stroke: A Case Report.

BACKGROUND: Meningovascular neurosyphilis, a form of early neurosyphilis, can cause infectious arteritis, which can be complicated by cerebral infarction. High-resolution vessel wall imaging (HR-VWI) is one of the techniques used to directly visualize the vessel wall. Herein, we present a rare case of meningovascular neurosyphilis, in which intracranial arterial vasculitis was evaluated using HR-VWI. CASE PRESENTATION: A 22-year-old man with no medical history of any condition was brought to the emergency room with one day history of right upper and lower extremity weakness. Diffusion-weighted magnetic resonance (MR) imaging showed a high signal from the left putamen to the corona radiata, and MR angiography showed stenosis of the right internal carotid artery (ICA) and the bilateral middle cerebral arteries (MCAs). HR-VWI showed thickening, along with smooth, intense, and concentric enhancement of the right ICA and the bilateral MCAs. The patient was diagnosed with neurosyphilis based on the findings of the blood tests and cerebrospinal fluid examination. The patient's symptoms gradually improved after treatment with intravenous penicillin G and oral antiplatelet agents. HR-VWI, performed approximately 6 months after the treatment, revealed improvement in the contrast enhancement of the vessel wall and the vascular stenosis. CONCLUSION: To the best of our knowledge, this is the first report of meningovascular neurosyphilis that evaluated the course of treatment using HR-VWI. Our report highlights the effectiveness of HR-VWI to determine the effects of treatment on meningovascular neurosyphilis.

Neurological Manifestations and Long-term Sequelae in Hospitalized Patients with COVID-19.

Objective Various neurological manifestations have been increasingly reported in coronavirus disease 2019 (COVID-19). We determined the neurological features and long-term sequelae in hospitalized COVID-19 patients. Methods We retrospectively studied 95 consecutive hospitalized patients with COVID-19 between March 1 and May 13, 2020. Acute neurological presentations (within two weeks of the symptom onset of COVID-19) were compared between 60 non-severe and 35 severely infected patients who required high-flow oxygen. In the 12 ventilated patients (the most severe group), we evaluated neurological complications during admission, subacute neurological presentations, and neurological sequelae (51 and 137 days from the onset [median], respectively). Results Of the 95 patients (mean age 53 years old; 40% women), 63% had acute neurological presentations, with an increased prevalence in cases of severe infections (83% vs. 52%, p<0.001). Impaired consciousness and limb weakness were more frequent in severe patients than in non-severe ones (0% vs. 49%; p<0.001, and 0% vs. 54%; p<0.001, respectively). In the most severe group (mean age 72 years old; 42% women), 83% of patients had neurological complications [cerebrovascular disease (17%), encephalopathy (82%), and neuropathy (55%)], and 92% had subacute neurological presentations [impaired consciousness (17%), higher brain dysfunction (82%), limb weakness (75%), and tremor (58%)]. Neurological sequelae were found in 83% of cases, including higher brain dysfunction (73%), limb weakness (50%), and tremor (58%). Conclusions Neurological manifestations are common in COVID-19, with the possibility of long-lasting sequelae.

[Effects of the prehospital care with and without suspecting acute stroke: a single stroke center study].

We retrospectively examined the differences between paramedic triage and final diagnosis in the cases that were transported to our hospital between May 2016 and March 2019. About 30% of the patients with suspected stroke were diagnosed other than stroke. Some of the patients without suspected stroke were diagnosed with large vessel occlusion and were treated with mechanical thrombectomy. The time from arrival at the hospital to treatment was significantly longer in the patients without suspected stroke than with suspected stroke. To achieve a better prehospital care, we need to accept a wide range of stroke mimics, and to continuously feedback the paramedics about the importance of paralysis, cortical symptoms in stroke.

Acute Internal Carotid Artery Occlusion Long after Carotid Revascularization by Vein Graft.

We report the case of a 27-year-old woman with acute internal carotid artery occlusion long after carotid artery revascularization by vein graft. She presented with sudden unconsciousness and left hemiparesis. Her right carotid artery was revascularized with an ipsilateral internal jugular vein graft during a carotid body tumor resection 10 years ago. Computed tomography angiography revealed a right internal carotid artery terminus occlusion. Intravenous rt-PA and mechanical thrombectomy were performed, resulting in successful recanalization. Her neurological symptoms gradually recovered. When examining the embolic source, carotid ultrasonography for the vein graft showed intimal thickening, some high-echoic plaques, and lumen dilation, but no thrombus was observed. Color Doppler imaging showed laminar flow at the graft. Angiography after thrombectomy also showed pooling of contrast at the vein graft. We suspected that the blood flow stagnation at the vein graft induced thrombus formation; therefore, anticoagulation therapy was initiated. One year later, she was independent without recurrence of stroke, and anticoagulation therapy was replaced with aspirin because she went abroad. However, a carotid ultrasonography exam the following year revealed a huge thrombus at the graft. Anticoagulation therapy was resumed; subsequently, the thrombus decreased. In conclusion, we could monitor the long-term change in the vein graft by ultrasonography. Moreover, anticoagulation therapy was more effective.

Carotid artery stenting before surgery for carotid artery occlusion associated with acute type A aortic dissection: Two case reports.

BACKGROUND: We experienced two cases of ischemic stroke resulting from carotid artery occlusion associated with acute type A aortic dissection (ATAAD), in which carotid artery stenting before the surgery for ATAAD resulted in good clinical outcomes.Case 1 description: A 63-year-old woman was hospitalized for conscious disturbance, right hemiparesis, and total aphasia. Computed tomography of the head showed no abnormal findings. Computed tomography angiography showed ATAAD and bilateral common carotid artery occlusion. Surgery was not indicated for ATAAD because of a poor prognosis of ischemic stroke. However, carotid artery stenting of the left common carotid artery occlusion was successfully performed, and her neurological findings improved. The patient underwent hemiarch replacement for ATAAD on the day after carotid artery stenting. Her final modified Rankin Scale was 1. Case 2 Description: A 57-year-old woman was hospitalized for mild left hemiparesis. Magnetic resonance imaging showed right watershed infarction and right common carotid artery occlusion. Computed tomography angiography showed ATAAD. After hospitalization, conscious disturbance appeared and left hemiparesis worsened. Ischemic stroke indicated a poor prognosis for revascularization by surgery for ATAAD. Thus, carotid artery stenting of the right common carotid artery occlusion was performed. The patient's neurological findings improved and she underwent hemiarch replacement for ATAAD at 19 days after carotid artery stenting. Her final modified Rankin Scale was 1. CONCLUSIONS: In the present cases, although ischemic stroke was serious and precluded surgical indication for ATAAD, carotid artery stenting before surgery for ATAAD resulted in good clinical outcomes. Performing carotid artery stenting before surgery for ATAAD is challenging but achievable, and is a valid treatment option depending on the individual cases.

A case of recanalization of innominate artery and right middle cerebral artery embolism due to cardiogenic cerebral infarction with anticoagulation therapy.

An 80-year-old woman had an aortic valve replacement 1 month before admission and took warfarin for transient atrial fibrillation. She developed a disturbance of consciousness and left hemiplegia. On admission, the right radial artery was slightly palpable. Head MRI images showed a hyper-intense area in the right middle cerebral artery territory. MRA images showed an occlusion of the right M1 distal site and decreased signal at the right internal carotid artery. Contrast CT images of the ascending aorta showed an embolus in the innominate artery. She was diagnosed with an innominate artery saddle embolus and occlusion of the right cerebral artery due to cardiac embolism. She was treated with a heparin infusion and warfarin. She recovered consciousness and from hemiplegia gradually. Recanalization of the innominate artery and right cerebral artery was confirmed. In cases where the radial artery is slightly palpable, it is necessary to consider an innominate artery saddle embolus in addition to aortic dissection.

The unfolding of alpha-momorcharin proceeds through the compact folded intermediate.

The unfolding of alpha-momorcharin was systematically investigated using steady-state and time-resolved tryptophan fluorescence, circular dichroism and 8-anilino-1-naphthalenesulfonic acid (ANS) binding. These spectroscopic studies demonstrated that alpha-momorcharin unfolded through a compact folded intermediate state. The content of alpha-helix was increased, Trp192 approached closer to the side of active site and its rotational motion was restricted by being equilibrated with 2-3 M of guanidine hydrochloride. Furthermore, the binding of ANS with alpha-momorcharin was more suppressed to show that the hydrophobic parts would not be accessed to the protein surface but rather be sealed off in this specific conformation state. These results suggest that the structure of alpha-momorcharin holds the more compact conformation as an incipient state for unfolding, which is the sharp contrast to beta-momorcharin that gives the characteristics of the generally known molten globule state.