Cross-Neutralizing Activity Against Omicron Could Be Obtained in SARS-CoV-2 Convalescent Patients Who Received Two Doses of mRNA Vaccination.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant omicron is now under investigation. We evaluated cross-neutralizing activity against omicron in coronavirus disease 2019 (COVID-19) convalescent patients (n = 23) who had received 2 doses of an mRNA vaccination (BNT162b2 or mRNA-1273). Intriguingly, after the second vaccination, the neutralizing antibody titers of subjects against SARS-CoV-2 variants, including omicron, all became seropositive, and significant fold-increases (21.1-52.0) were seen regardless of the disease severity. Our findings thus demonstrate that 2 doses of mRNA vaccination to SARS-CoV-2 convalescent patients can induce cross-neutralizing activity against omicron.

Cross-Neutralizing Breadth and Longevity Against SARS-CoV-2 Variants After Infections.

Background: Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is the virus responsible for the Coronavirus Disease 2019 (COVID-19) pandemic. The emergence of variants of concern (VOCs) has become one of the most pressing issues in public health. To control VOCs, it is important to know which COVID-19 convalescent sera have cross-neutralizing activity against VOCs and how long the sera maintain this protective activity. Methods: Sera of patients infected with SARS-CoV-2 from March 2020 to January 2021 and admitted to Hyogo Prefectural Kakogawa Medical Center were selected. Blood was drawn from patients at 1-3, 3-6, and 6-8 months post onset. Then, a virus neutralization assay against SARS-CoV-2 variants (D614G mutation as conventional strain; B.1.1.7, P.1, and B.1.351 as VOCs) was performed using authentic viruses. Results: We assessed 97 sera from 42 patients. Sera from 28 patients showed neutralizing activity that was sustained for 3-8 months post onset. The neutralizing antibody titer against D614G significantly decreased in sera of 6-8 months post onset compared to those of 1-3 months post onset. However, the neutralizing antibody titers against the three VOCs were not significantly different among 1-3, 3-6, and 6-8 months post onset. Discussion: Our results indicate that neutralizing antibodies that recognize the common epitope for several variants may be maintained for a long time, while neutralizing antibodies having specific epitopes for a variant, produced in large quantities immediately after infection, may decrease quite rapidly.

Reversible magnetic resonance imaging changes associated with hypoglycemia. Case report.

A 63-year-old man was found with confusion and right limb monoparesis. He was taken to the emergency center under suspicion of stroke. Head computed tomography and magnetic resonance (MR) imaging and MR angiography were immediately conducted, which revealed no abnormality, but diffusion-weighted imaging showed increased intensity areas in the splenium of the corpus callosum and the left posterior limb of the internal capsule with decreased apparent diffusion coefficient (ADC) in the same areas. Immediately after the head scan, blood sugar level was measured, which revealed hypoglycemia (23 mg/dl). He quickly became lucid after intravenous administration of 20 ml of 50% glucose solution, and the paresis disappeared. Follow-up brain MR imaging was conducted 3 days later, but no clearly abnormal findings were seen on T(2)-weighted, fluid-attenuated inversion recovery, diffusion-weighted, or ADC images. Reports of reversible high intensity area in the splenium of the corpus callosum on diffusion-weighted imaging due to transient hypoglycemia are rare. Hemiparesis is one of the manifestations of hypoglycemia, so verifying the blood sugar level is important. Since MR imaging can be conducted easily now, we may need to consider the imaging findings in the differential diagnosis of hypoglycemia.

Predictors of intracerebral hemorrhage severity and its outcome in Japanese stroke patients.

OBJECTIVE: The aim of this investigation was to determine the factors influencing acute intracerebral hemorrhage severity on admission and clinical outcomes at discharge. METHODS: Sixty acute stroke hospitals throughout Japan participated in the Japan Standard Stroke Registry Study (JSSRS), documenting the in-hospital course of 16,630 consecutive patients with acute stroke from January 2001 to March 2004. We identified 2,840 adult patients from the JSSRS who had intracerebral hemorrhage. RESULTS: Intracerebral hemorrhage severity on admission was strongly related to age, previous stroke history, and hemorrhage size in a monotone fashion [chi(2)(9) = 374.5, p < 0.0001]. Drinking history was also predictive of intracerebral hemorrhage severity on admission, but the association was not monotone. Interestingly, intracerebral hemorrhage severity on admission was increased in nondrinking and heavy drinking compared to mild drinking (p < 0.05). Unsuccessful outcome (modified Rankin scale score = 3-6) was related to age, previous stroke history, hemorrhage size, and intracerebral hemorrhage severity on admission [chi(2)(9) = 830.4, p < 0.0001]. Mortality was related to hemorrhage size, intraventricular hemorrhage, intracerebral hemorrhage severity on admission, and surgical operation [chi(2)(7) = 540.4, p < 0.0001]. CONCLUSION: We could find four varied factors associated with intracerebral hemorrhage severity and its outcomes. Interestingly, intracerebral hemorrhage severity tended to be greater in nondrinking and heavy drinking than mild drinking. Additionally, surgical operation decreased intracerebral hemorrhage mortality.

Plasma brain natriuretic peptide as a surrogate marker for cardioembolic stroke.

BACKGROUND: Cardioembolic stroke generally results in more severe disability, since it typically has a larger ischemic area than the other types of ischemic stroke. However, it is difficult to differentiate cardioembolic stroke from non-cardioembolic stroke (atherothrombotic stroke and lacunar stroke). In this study, we evaluated the levels of plasma brain natriuretic peptide in acute ischemic stroke patients with cardioembolic stroke or non-cardioembolic stroke, and assessed the prediction factors of plasma brain natriuretic peptide and whether we could differentiate between stroke subtypes on the basis of plasma brain natriuretic peptide concentrations in addition to patient's clinical variables. METHODS: Our patient cohort consisted of 131 consecutive patients with acute cerebral infarction who were admitted to Kagawa University School of Medicine Hospital from January 1, 2005 to December 31, 2007. The mean age of patients (43 females, 88 males) was 69.6 +/- 10.1 years. Sixty-two patients had cardioembolic stroke; the remaining 69 patients had non-cardioembolic stroke (including atherothrombotic stroke, lacunar stroke, or the other). Clinical variables and the plasma brain natriuretic peptide were evaluated in all patients. RESULTS: Plasma brain natriuretic peptide was linearly associated with atrial fibrillation, heart failure, chronic renal failure, and left atrial diameter, independently (F4,126 = 27.6, p < 0.0001; adjusted R2 = 0.45). Furthermore, atrial fibrillation, mitral regurgitation, plasma brain natriuretic peptide (> 77 pg/ml), and left atrial diameter (> 36 mm) were statistically significant independent predictors of cardioembolic stroke in the multivariable setting (Chi2 = 127.5, p < 0.001). CONCLUSION: It was suggested that cardioembolic stroke was strongly predicted with atrial fibrillation and plasma brain natriuretic peptide. Plasma brain natriuretic peptide can be a surrogate marker for cardioembolic stroke.

Brain natriuretic peptide as a surrogate marker for cardioembolic stroke with paroxysmal atrial fibrillation.

BACKGROUND: Cardioembolic stroke generally results in severer disability, since it typically has a larger ischemic area than the other types of ischemic stroke. However, it is difficult to differentiate cardioembolic from noncardioembolic stroke (atherothrombotic and lacunar stroke), whenever ischemic stroke patients have sinus rhythm at the time of presentation. METHODS: In this study, we evaluated the levels of plasma brain natriuretic peptide in acute ischemic stroke patients with cardioembolic or noncardioembolic stroke and assessed whether this could provide a basis for differentiating cardioembolic stroke (especially due to paroxysmal atrial fibrillation) from noncardioembolic stroke. Our patient cohort consisted of 99 consecutive patients with acute cerebral infarction who were admitted to Kagawa University School of Medicine Hospital from January 1, 2005, to December 31, 2006. We excluded 23 patients with valve disease, heart failure, myocardial infarction or chronic renal failure. The mean age of the remaining 76 patients (51 males, 25 females) was 70.0 +/- 10.1 years. RESULTS: Thirty-six patients had cardioembolic stroke with atrial fibrillation (including permanent and paroxysmal atrial fibrillation); the remaining 40 had noncardioembolic stroke. The plasma brain natriuretic peptide was evaluated on the first morning after admission in all patients. In cardioembolic stroke with atrial fibrillation (permanent and paroxysmal atrial fibrillation), the plasma brain natriuretic peptide, ratio of peak early filling velocity to peak atrial systolic velocity (E/A) and left atrial diameter were significantly increased (p < 0.001), and the left atrial appendage flow was significantly decreased (p < 0.001), compared with noncardioembolic stroke. Analyzed in those 4 factors, cardioembolic stroke was strongly predicted with >95% accuracy assessed by plasma brain natriuretic peptide and left atrial appendage flow. CONCLUSION: From our results, it was suggested that the first-day brain natriuretic peptide and left atrial appendage flow measurements would be helpful in differentiating cardioembolic stroke with atrial fibrillation from noncardioembolic stroke.