alzheimer's disease (ad) is the most prevalent age-related neurodegenerative disorder. it is featured by the progressive accumulation of β-amyloid (aβ) plaques and neurofibrillary tangles. This can eventually lead to a decrease of cholinergic neurons in the basal forebrain. Stem cell transplantation is an effective treatment for neurodegenerative diseases. Previous studies have revealed that different types of stem or progenitor cells can mitigate cognition impairment in different alzheimer's disease mouse models. However, understanding the underlying mechanisms of neural stem cell (nSc) therapies for ad requires further investigation. in the present study, the effects and the underlying mechanisms of the treatment of ad by nScs are reported. The latter were labelled with the enhanced green fluorescent protein (EGFP) prior to implantation into the bilateral hippocampus of an amyloid precursor protein (aPP)/presenilin 1 (PS1) transgenic (Tg) mouse model of ad. it was observed that the number of basal forebrain cholinergic neurons was restored and the expression of choline acetyltransferase (chaT) protein was increased. Moreover, the levels of synaptophysin (SYP), postsynaptic density protein 95 (PSd-95) and microtubule-associated protein (MaP-2) were significantly increased in the hippocampus of NSC-treated ad mice. notably, spatial learning and memory were both improved after transplantation of nScs. in conclusion, the present study revealed that nSc transplantation improved learning and memory functions in an ad mouse model. This treatment allowed repairing of basal forebrain cholinergic neurons and increased the expression of the cognition-related proteins SYP, PSd-95 and MaP-2 in the hippocampus.

Human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein 120 (gp120) has been reported to be toxic to the hippocampal neurons, and to be involved in the pathogenesis of HIV-1-associated neurocognitive disorders (HAND). Accumulating evidence has demonstrated that voltage-gated potassium (Kv) channels, especially the outward delayed-rectifier K(+) (Ik) channels, play a critical role in gp120-induced cortical neuronal death in vitro. However, the potential mechanisms underlying the hippocampal neuronal injury resulted from gp120-mediated neurotoxicity remain poorly understood. Using whole-cell patch clamp recording in cultured hippocampal neurons, this study found that gp120 significantly increased the outward delayed-rectifier K(+) currents (Ik). Meanwhile, Western blot assay revealed that gp120 markedly upregulated Kv2.1 protein levels, which was consistent with the increased Ik density. With Western blot and terminal deoxynucleotidyl transferase dUTP nick end labeling assays, it was discovered that gp120-induced neuronal injury was largely due to activation of Kv2.1 channels and resultant apoptosis mediated by caspase-3 activation, as the pharmacological blockade of Kv2.1 channels largely attenuated gp120-induced cell damage and caspase-3 expression. Moreover, p38 MAPK was demonstrated to participate in gp120-induced hippocampal neural damage, since p38 MAPK antagonist (SB203580) partially abrogated gp120-induced Kv2.1 upregulation and neural apoptosis. Taken together, these results suggest that gp120 induces hippocampal neuron apoptosis by enhancement of the Ik, which might be associated with increased Kv2.1 expression via the p38 MAPK pathway.

Since the dental structure and the mechanical parameters of dental hard tissues would affect the propagation features of ultrasonic waves, laser ultrasonic nondestructive evaluation (NDE) technique can be used to assess human teeth. With the application of an expansion Laguerre polynomial technique, surface acoustic waves (SAW) in human incisors are calculated, and the effects of inhomogeneous elastic properties of enamel and initial dental caries on SAW are also discussed. An experimental setup to generate and detect SAW in incisor by noncontact and nondestructive manner is established. A focused laser line source is used to generate broadband SAW, which is detected by laser Dopple vibrometer on healthy incisor and initial dental carious, respectively. The results demonstrate that some dental parameters such as dental structures and initial dental carious can affect the phase velocities of laser induced SAW. Laser ultrasonic NDE methods have the potential for evaluation of human teeth in vivo.

ObjectivesTo explore the prognostic value of magnetic resonance image compilation (MAGiC) in the quantitative assessment of neonatal hypoglycemic encephalopathy (HE).MethodsA total of 75 neonatal HE patients who underwent synthetic MRI were included in this retrospective study. Perinatal clinical data were collected. T1, T2 and proton density (PD) values were measured in the white matter of the frontal lobe, parietal lobe, temporal lobe and occipital lobe, centrum semiovale, periventricular white matter, thalamus, lenticular nucleus, caudate nucleus, corpus callosum and cerebellum, which were generated by MAGiC. The patients were divided into two groups (group A: normal and mild developmental disability; group B: severe developmental disability) according to the score of Bayley Scales of Infant Development (Bayley III) at 9–12 months of age. Student’s t test, Wilcoxon test, and Fisher’s test were performed to compare data across the two groups. Multivariate logistic regression was used to identify the predictors of poor prognosis, and receiver operating characteristic (ROC) curves were created to evaluate the diagnostic accuracy.ResultsT1 and T2 values of the parietal lobe, occipital lobe, center semiovale, periventricular white matter, thalamus, and corpus callosum were higher in group B than in group A (p < 0.05). PD values of the occipital lobe, center semiovale, thalamus, and corpus callosum were higher in group B than in group A (p < 0.05). Multivariate logistic regression analysis showed that the duration of hypoglycemia, neonatal behavioral neurological assessment (NBNA) scores, T1 and T2 values of the occipital lobe, and T1 values of the corpus callosum and thalamus were independent predictors of severe HE (OR > 1, p < 0.05). The T2 values of the occipital lobe showed the best diagnostic performance, with an AUC value of 0.844, sensitivity of 83.02%, and specificity of 88.16%. Furthermore, the combination of MAGiC quantitative values and perinatal clinical features can improve the AUC (AUC = 0.923) compared with the use of MAGiC or perinatal clinical features alone.ConclusionThe quantitative values of MAGiC can predict the prognosis of HE early, and the prediction efficiency is further optimized after being combined with clinical features.