Elderly population have a decreased aneurysmal subarachnoid hemorrhage incidence rate than Middle aged population: a descriptive analysis of 8,144 cases in mainland China.

PURPOSE: Rupture of an intracranial aneurysm is a life-threatening acute cerebrovascular event. The purpose of this study was to investigate whether aneurysmal subarachnoid haemorrhage (SAH) incidence rate is higher or lower in elderly population than in middle aged population. MATERIALS AND METHODS: Aneurysmal SAH cases were collected retrospectively from the archives of 21 hospitals in Mainland China. All the cases were collected from September 2016 and backward consecutively for a period of time up to 8 years. SAH was initially diagnosed by brain computed tomography (CT). CT angiography (CTA) or digital subtraction angiography (DSA) was followed and SAH was confirmed to be due to cerebral aneurysm rupture. For cases when multiple bleeding occurred, the age of the first SAH was used in this study. The total incidence from all hospitals at each age group were summed together for females and males respectively; then adjusted by the total population number at each age group for females and males which was from the 2010 population census of the People's Republic of China. RESULTS: In total there were 8,144 cases of intracranial aneurysmal SAH, with 4,861 females and 3,283 males. For females the relative aneurysmal SAH incidence rate started to decrease after around 65 years old, while for males the relative aneurysmal SAH incidence rate started to decrease after around 53 years old. CONCLUSION: Our data tentatively suggest elderly patients may be at a reduced risk of rupture compared with patients who are younger while have similar other risk factors.

Strip biosensor for amplified detection of nerve growth factor-beta based on a molecular translator and catalytic DNA circuit.

We have demonstrated a new visual detection approach based on a molecular translator and a catalytic DNA circuit for the detection of nerve growth factor-beta (NGF-ß). In this assay, a molecular translator based on the binding-induced DNA strand-displacement reaction was employed to convert the input protein to an output DNA signal. The molecular translator is composed of a target recognition element and a signal output element. Target recognition is achieved by the binding of the anti-NGF-ß antibody to the target protein. Polyclonal anti-NGF-ß antibody is conjugated to DNA1 and DNA2. The antibody conjugated DNA1 is initially hybridized to DNA3 to form a stable DNA1/DNA3 duplex. In the presence of NGF-ß, the binding of the same target protein brings DNA1 and DNA2 into close proximity, resulting in an increase in their local effective concentration. This process triggers the strand-displacement reaction between DNA2 and DNA3 and releases the output DNA3. The released DNA3 is further amplified by a catalytic DNA circuit. The product of the catalytic DNA circuit is detected by a strip biosensor. This proposed assay has high sensitivity and selectivity with a dynamic response ranging from 10 fM to 10 pM, and its detection limit is 10 fM of NGF-ß. This work provides a sensitive, enzyme-free, and universal strategy for the detection of other proteins.

Electroencephalogram beta power assay: a promising diagnosis tool of cognitive impairment in early time after cerebral hemorrhage.

BACKGROUND: Cerebral hemorrhage (CH) could affect the cerebral function on specific cognitive abilities and lead to the cognitive decline or cognitive dysfunction. Electroencephalogram (EEG) is a relatively cheap and easy usable tool, which could reflect the cerebral function of the patients. MATERIALS AND METHODS: A total of 170 patients (patients with and without cognitive impairment) with CH and 120 normal healthy controls were recruited from September 2008 to June 2012 at the Department of Neurology. EEG studies were carried out to analyze the cerebral function in all the subjects. Correlation, clustering and concordance analysis were performed to analyze the relationship between EEG power and Montreal cognitive assessment (MoCA) scores. The effects of EEG analysis were assessed to diagnosis the cognitive impairment. RESULTS: The results were showed that patients with cognitive impairment had a significantly decreased EEG beta power (0.771 ± 0.149 µV 2 ) compared with the normal cognitive function (1.654 ± 0.186 µV 2 , P < 0.01) or normal healthy controls (1.703 ± 0.216 µV 2 , P < 0.01). Significantly positive correlation (r = 0.90174, P < 0.001) was discovered between relative beta power and hemorrhage type, while significantly negative correlations between the relative beta power and hemorrhage size and amount were also observed (r =-0.81235 and r =-0.90136, respectively, all P < 0.001). There was a better concordance between K-means clustering algorithm calculating of the relative beta power and MoCA scores (κ =0.913, P < 0.001). CONCLUSION: The cognitive impairment post hemorrhage was positively correlated to hemorrhage type and negatively correlated with hemorrhage size and amount. The analysis method of EEG beta power abnormality holds a promise to assess the cognitive impairment post CH.