A Point-of-Care Testing Device Utilizing Graphene-Enhanced Fiber Optic SPR Sensor for Real-Time Detection of Infectious Pathogens.

Timely detection of highly infectious pathogens is essential for preventing and controlling public health risks. However, most traditional testing instruments require multiple tedious steps and ultimately testing in hospitals and third-party laboratories. The sample transfer process significantly prolongs the time to obtain test results. To tackle this aspect, a portable fiber optic surface plasmon resonance (FO-SPR) device was developed for the real-time detection of infectious pathogens. The portable device innovatively integrated a compact FO-SPR sensing component, a signal acquisition and processing system, and an embedded power supply unit. A gold-plated fiber is used as the FO-SPR sensing probe. Compared with traditional SPR sensing systems, the device is smaller size, lighter weight, and higher convenience. To enhance the detection capacity of pathogens, a monolayer graphene was coated on the sensing region of the FO-SPR sensing probe. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was used to evaluate the performance of the portable device. The device can accurately detect the SARS-CoV-2 spike S1 protein in phosphate-buffered saline (PBS) and artificial saliva within just 20 min, and the device successfully detected cultured SARS-CoV-2 virus. Furthermore, the FO-SPR probe has long-term stability, remaining stable for up to 8 days. It could distinguish between the SARS-CoV-2 spike protein and the MERS-CoV spike protein. Hence, this FO-SPR device provides reliable, rapid, and portable access to test results. It provides a promising point-of-care testing (POCT) tool for on-site screening of infectious pathogens.

Rotational vertebral artery occlusion in a patient with basilar invagination.

Basilar invagination (BI) is a congenital or acquired craniovertebral junction (CVJ) anomaly with odontoid process superiorly migrating into the foramen magnum. Compression of neural structures is the most relevant complication of BI. However BI is also a rare cause of ischemic stroke. In this case we reported a 30-year-old female with BI who developed recurrent ischemic stroke in posterior circulation. Before the onset of ischemic stroke, she didn't present neck pain or clinical signs of lower cranial nerve dysfunction, brainstem compression or transient ischemic attack. At first she suffered from sudden onset of left-sided hemidysesthesia. Magnetic resonance imaging from a local hospital revealed an acute infarction in the right thalamus. Cerebral MR angiography was unremarkable at that time. The tip of the odontoid process had protruded into the foramen magnum and could be observed at the level of the lower medulla, but unfortunately it was ignored by the clinicians and the radiologists. She was given antiplatelet therapy and the sensory disturbance disappeared gradually. However she experienced a recurrence in the pontine and midbrain region 2 months later. At this time she was transferred to our hospital, and reconstructed computed tomography of cervical spine demonstrated basilar invagination, atlanto-axial dislocation, and atlanto-occipital assimilation. Computed tomographic angiography (CTA) revealed a dominant right vertebral artery (VA) and a redundant loop in its third segment. Dynamic cerebral angiogram demonstrated that the patient had a Bow Hunter's type phenomenon, with dynamic occlusion of the right dominant VA during contralateral head turn. This case highlighted the necessary of hemodynamic evaluation in asymptomatic basilar invagination.

Pramipexole Inhibits Neuronal Apoptosis in Rats with Parkinson's Disease.

To explore the inhibition of pramipexole on the neuronal apoptosis and its influences on the expressions of brain tissue brain-derived neurotrophic factor (BDNF), and serum miR-103a and miR-30b and inflammatory factors in rats with Parkinson's disease. A total of 36 Sprague-Dawley rats were randomly divided into normal group (n = 12), model group (n = 12) and pramipexole group (n = 12). Compared with that in normal group, the positive expression of BDNF was substantially increased in model group and pramipexole group, and its positive expression in pramipexole group was notably higher than that in model group. The WB results revealed that compared with those in normal group, the relative protein expression levels of Bax and Bcl-2 were markedly increased and decreased, respectively, in the other two groups, and that pramipexole group exhibited a remarkable decline in the relative protein expression level of Bax and a considerable increase in that of Bcl-2, compared with model group. The relative expression levels of miR-103a and miR-30b in model and pramipexole groups were markedly higher than those in normal group, and pramipexole group had remarkably higher relative expression levels of miR-103a and miR-30b than model group. It was found through ELISA that model and pramipexole groups had markedly raised IL-1ß and IL-18 content compared with normal group, and their content in pramipexole group was remarkably lower than that in model group. Based on the TUNEL results, compared with that in normal group, the apoptosis rate of cells rose substantially in the other two groups, and the apoptosis rate in pramipexole group was notably lower than that in model group. Pramipexole may up-regulate the expressions of BDNF, miR-103a and miR-30b to inhibit the apoptosis and inflammation in Parkinson's disease model rats.

Bilateral Meningo-Cortical Involvement in Anti-myelin Oligodendrocyte Glycoprotein-IgG Associated Disorders: A Case Report.

Cortical T2-weighted fluid-attenuated inversion recovery (FLAIR)-hyperintense lesions in anti-myelin oligodendrocyte glycoprotein (MOG)-associated encephalitis with seizures (FLAMES) are mostly unilateral and rarely spread to the bilateral cortex and meninges. We describe a case of MOG-immunoglobulin G (IgG) associated disorder (MOGAD) in a 39-year-old male with bilateral meningo-cortical involvement. The patient was hospitalized for epilepsy, fever, and headache. The initial MRI revealed abnormalities in the sulci of the bilateral frontal, temporal, and parietal lobes. He was considered to have infectious encephalitis and given empiric antibiotic and antiviral therapy, which were ineffective. His condition rapidly improved after the patient was switched to high-dose immunoglobulin therapy. No tests supported the presence of central nervous system (CNS) infections or autoimmune encephalitis. The second and third MRI scans showed reduced but still clearly observable meningo-cortical lesions. The patient was discharged without a definite diagnosis, but reported severe left vision impairment 25 days later. A fourth MRI showed signs typical of demyelinating CNS disease in addition to the original meningo-cortical lesions. The patient's symptoms were initially relieved by low-dose corticosteroid therapy, but they eventually returned, and he was re-admitted. The original lesions were diminished on the fifth MRI scan, but new lesions had developed in the deep white matter. A positive cell-based assay for MOG-IgG in serum confirmed MOGAD. The patient received high-dose corticosteroid treatment followed by an oral methylprednisolone taper, and his visual acuity gradually improved. The sixth and final MRI showed substantial decreases in the original lesions without new lesion formation. This unique case presents the complete diagnosis and treatment process for MOGAD with bilateral meningo-cortical involvement and may provide a reference for prompt diagnosis.

Fiber birefringence measurement by an external applied strain method and a polarimetric fiber laser sensor.

In this work, a high-sensitivity and low-cost sensing scheme for measuring intrinsic and induced fiber birefringence change is reported based on a polarimetric fiber laser sensor interrogated by the beat frequency technique. The fiber birefringence measurement is achieved by an external applied strain method. A detailed theoretical analysis of the principle for fiber birefringence measurement is carried out. Two alternative equations are given for determining the change of fiber birefringence, which make it very convenient for users to choose different order beat signals. To verify the performance of the sensing system, the external applied strain-induced fiber birefringence change is measured experimentally. The experiment result shows that the fiber birefringence experiences a linear increase with the increase of applied strain. A strain response coefficient of 4.646×10-11/µÏµ is obtained. Furthermore, the repeatability and stability performances of the polarimetric fiber laser sensor are also investigated.

Blend sign predicts poor outcome in patients with intracerebral hemorrhage.

INTRODUCTION: Blend sign has been recently described as a novel imaging marker that predicts hematoma expansion. The purpose of our study was to investigate the prognostic value of CT blend sign in patients with ICH. OBJECTIVES AND METHODS: Patients with intracerebral hemorrhage who underwent baseline CT scan within 6 hours were included. The presence of blend sign on admission nonenhanced CT was independently assessed by two readers. The functional outcome was assessed by using the modified Rankin Scale (mRS) at 90 days. RESULTS: Blend sign was identified in 40 of 238 (16.8%) patients on admission CT scan. The proportion of patients with a poor functional outcome was significantly higher in patients with blend sign than those without blend sign (75.0% versus 47.5%, P = 0.001). The multivariate logistic regression analysis demonstrated that age, intraventricular hemorrhage, admission GCS score, baseline hematoma volume and presence of blend sign on baseline CT independently predict poor functional outcome at 90 days. The CT blend sign independently predicts poor outcome in patients with ICH (odds ratio 3.61, 95% confidence interval [1.47-8.89];p = 0.005). CONCLUSIONS: Early identification of blend sign is useful in prognostic stratification and may serve as a potential therapeutic target for prospective interventional studies.

Value of CXCL13 in diagnosing asymptomatic neurosyphilis in HIV-infected patients.

Diagnosing asymptomatic neurosyphilis (ANS) in HIV-infected patients is difficult. A recent report suggested that CXCL13 is a promising diagnostic marker for neurosyphilis in HIV-positive patients. However, whether CXCL13 can be a diagnostic marker for ANS in HIV-infected patients remains unknown. The purpose of our study was to determine the role of CXCL13 in diagnosing ANS in HIV-infected patients. This study comprised two study and three control groups. Two study groups included 12 HIV-infected patients with ANS and 25 patients with syphilis and HIV co-infection (without ANS). Three control groups included 9 patients with ANS without HIV infection, 25 HIV-infected patients without syphilis and 10 healthy volunteers. Concentrations of CSF CXCL13 were measured before and after neurosyphilis therapy. Our results showed that CSF CXCL13 concentrations were significantly increased in all of the HIV-infected patients with ANS, the 25 HIV patients with syphilis and the 9 ANS patients without HIV, but not in the patients of the other two control groups. CSF CXCL13 concentrations declined in the two study groups of patients following neurosyphilis therapy. Therefore, CSF CXCL13 concentrations could improve the diagnosis of ANS in HIV-infected patients.