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Circadian rhythm disruption (CRD) is a potential risk factor for developing Alzheimer's disease (AD). However, the mechanistic link between CRD and AD is still not fully understood. CRD may lead to intestinal barrier impairment. Several studies in animals and humans suggest a connection between gut microbiota disturbance, intestinal barrier damage and neurodegenerative diseases. In this study, we investigated the effect of CRD on cognition in mice and explored the role of intestinal barrier and inflammatory responses in this process. CRD modulates the composition of gut microbiota, impairs intestinal barrier integrity, and induces both peripheral and central inflammation and cognitive impairment in mice. Rifaximin, a non-absorbable antibiotic which modulates the gut microbial composition and increases intestinal barrier integrity, effectively suppresses inflammatory responses, and rescues cognitive impairment induced by CRD. Furthermore, the impairment in hippocampal neurogenesis, tau hyperphosphorylation, and loss in synaptic proteins in CRD mice is also reversed by Rifaximin. These data identify that the impaired intestinal barrier integrity related to gut microbiota disturbance plays a key role in CRD-induced inflammatory responses and cognitive impairments in mice, and Rifaximin is effective in preventing CRD-induced cognitive deficit through protecting the gut barrier and ameliorating neuroinflammation.

Cancerous Inhibitor of PP2A (CIP2A), an endogenous PP2A inhibitor, is upregulated and causes reactive astrogliosis, synaptic degeneration, and cognitive deficits in Alzheimer's disease (AD). However, the mechanism underlying the increased CIP2A expression in AD brains remains unclear. We here demonstrated that the DNA damage-related Checkpoint kinase 1 (ChK1) is activated in AD human brains and 3xTg-AD mice. ChK1-mediated CIP2A overexpression drives inhibition of PP2A and activates STAT3, then leads to reactive astrogliosis and neurodegeneration in vitro. Infection of mouse brain with GFAP-ChK1-AAV induced AD-like cognitive deficits and exacerbated AD pathologies in vivo. In conclusion, we showed that ChK1 activation induces reactive astrogliosis, degeneration of neurons, and exacerbation of AD through the CIP2A-PP2A-STAT3 pathway, and inhibiting ChK1 may be a potential therapeutic approach for AD treatment.

Polyphyllin I (PPI) is a natural phytochemical drug isolated from plants which can inhibit the proliferation of cancer cells. One of the PPI tumor-inhibitory effects is through downregulating the expression of Cancerous Inhibitor of PP2A (CIP2A), the latter, is found upregulated in Alzheimer's disease (AD) brains and participates in the development of AD. In this study, we explored the application of PPI in experimental AD treatment in CIP2A-overexpressed cells and 3XTg-AD mice. In CIP2A-overexpressed HEK293 cells or primary neurons, PPI effectively reduced CIP2A level, activated PP2A, and decreased the phosphorylation of tau/APP and the level of Aβ. Furthermore, synaptic protein levels were restored by PPI in primary neurons overexpressing CIP2A. Animal experiments in 3XTg-AD mice revealed that PPI treatment resulted in decreased CIP2A expression and PP2A re-activation. With the modification of CIP2A-PP2A signaling, the hyperphosphorylation of tau/APP and Aβ overproduction were prevented, and the cognitive impairments of 3XTg-AD mice were rescued. In summary, PPI ameliorated AD-like pathology and cognitive impairment through modulating CIP2A-PP2A signaling pathway. It may be a potential drug candidate for the treatment of AD.

The mechanism of exosomes derived from activated hepatic stellate cells (HSCs) involved in liver fibrosis is poorly understood. We previously reported that hypoxia-inducible factor 1 (Hif-1) regulated HSC activation, and, therefore, we investigated in current work whether Hif-1 regulates exosome secretion and the metabolic switch of HSCs, thus affecting the metabolism of liver nonparenchymal cells. In this study, the characteristics of exosomes from HSCs were assessed via electron microscopy, Western blot analysis, and acetylcholinesterase activity. Confocal microscopy was used to measure the uptake of exosomes by quiescent HSCs, Kupffer cells (KCs), and liver sinusoidal endothelial cells (LSECs). Hif-1α was inhibited via 2-ME or specific small interfering RNAs to investigate its role in exosomes derived from HSCs. It was determined that glucose transporter 1 and pyruvate kinase M2 were increasingly expressed in fibrotic liver samples, cell lysates, and exosomes derived from activated HSCs. Exosomes released from HSCs were associated with activation and glucose uptake of HSCs. Delivery of exosomes from activated HSCs induced glycolysis of quiescent HSCs, KCs, and LSECs. Disruption of Hif-1 expression suppressed the glycolysis effect delivered by exosomes. Conclusively, our results demonstrated that exosomes secreted by activated HSCs affect the metabolic switch of liver nonparenchymal cells via delivery of glycolysis-related proteins. These findings represent a novel mechanism that contributes to liver fibrosis and has significant implications for new diagnosis and treatment of liver diseases.-Wan, L., Xia, T., Du, Y., Liu, J., Xie, Y., Zhang, Y., Guan, F., Wu, J., Wang, X., Shi, C. Exosomes from activated hepatic stellate cells contain GLUT1 and PKM2: a role for exosomes in metabolic switch of liver nonparenchymal cells.

Objective We aimed to use next‐generation sequencing (NGS) for the early diagnosis of primary immunodeficiency diseases (PIDs) and define its effects on medical management for an infant cohort in early life. Methods A single‐centre study was conducted from November 2015 to April 2018. Infants less than 3 months old with infections or abnormal white blood cell counts were enrolled in the study. Gene variants were analysed by NGS, and once a mutation was found in a PID‐associated gene, the immune functions associated with this mutation were detected. The diagnosis rate of PIDs in the cohort was the main outcome. The patients received corresponding management and follow‐up treatments. Results Among 2392 patients who were genetically tested with NGS, 51 infants were diagnosed with PIDs. Seven types of PIDs were detected, and the most common (25/51, 49%) were combined immunodeficiencies with associated or syndromic features. Thirty‐five patients (68.6%) were cured or had improved outcomes after being diagnosed with PID. The NGS cost was US$280 per case. Conclusions This study not only highlighted the potential of NGS to rapidly deliver molecular diagnoses of PIDs but also indicated that the prevalence of PIDs is underestimated. With broader use, this approach has the potential to alter clinical strategies., This study highlights advantages of next‐generation sequencing for primary immunodeficiency diseases (PID) screening in early life infants. Based on the diagnosis, early precision therapy improved the prognosis of individuals with PIDs.

BACKGROUND It is known that a neurologic sequence occurs at high altitudes (HA); hence, cerebral blood flow (CBF) might vary by altitude. PURPOSE To use arterial spin labeled (ASL) MRI to evaluate absolute CBF differences between subjects who live at HA and lowlands. STUDY TYPE Cohort prospective trial. POPULATION In all, 64 HA Tibetans, 19 lowland Tibetans, and 25 lowland Han subjects. FIELD STRENGTH/SEQUENCE CBF was measured with the pulsed ASL sequence at 3T. ASSESSMENT CBF was correlated with abode altitude in HA Tibetans; CBF differences among HA Tibetans, lowland Tibetans, and lowland Han subjects was assessed. STATISTICAL TESTS Pearson correlation assessed the correlation. Independent t-tests analyzed group differences. RESULTS In HA Tibetans, CBF decreased with altitude in the bilateral anterior and posterior cingulate gyri, fusiform gyrus, cerebellar tonsil and cortices, and thalamus as well as left middle and inferior temporal gyri and right insula (P

BACKGROUND MRI signal diffusion-weighted imaging (DWI) hyperintensity in the hippocampus in patients with transient global amnesia (TGA) are resolved within several days after the onset of TGA. PURPOSE To use multiparametric MRI to unravel the sequelae of TGA. STUDY TYPE A prospective longitudinal study. POPULATION Eight TGA patients. FIELD STRENGTH/SEQUENCE A 3.0T Siemens Tim Trio MRI scanner with T1-weighted MPRAGE, diffusion-weighted echo planar imaging, and multiecho gradient-recalled echo sequences. ASSESSMENT Brain MRI scanned within 72 hours, 2 weeks, and 3 months after onset of TGA, respectively. T1 image hippocampus was first segmented into 12 subregions using FreeSurfer and registered to DWI to locate DWI lesion. Then a T1 image with segmented hippocampus was registered to its corresponding apparent diffusion coefficient (ADC) map, fractional anisotropy (FA) map, and quantitative susceptibility map, respectively. Finally, the volume, water diffusion and anisotropy, and magnetic susceptibility of DWI lesion were analyzed. STATISTICAL TESTS A paired samples t-test was performed to detect measurement differences between three tests. Pearson correlation was used to assess the correlations between all measurements. RESULTS Hyperintensity was detected in the head, body, and caudate of CA1 and hippocampal tail. No significant changes existed in CA1/unit volume across the three timepoint measurements (all, P > 0.480). In Test 1, ratio ADC (DWI lesion / adjacent healthy, rADC) and ratio FA (rFA) decreased below, while ratio susceptibility increased above 1.0. In Test 2, all the episodes normalized around 1.0. In Test 3, rADC remained normalization, but rFA decreased and ratio susceptibility increased again. In Test 1 and Test 3 (vs. Test 2), decreased FA values were accompanied with lower axial diffusivity and/or higher radial diffusivity (all, P < 0.001). Moreover, rFA significantly correlated with ratio susceptibility in Test 3 (r = −0.665, P = 0.039). DATA CONCLUSION Microstructural sequelae in hippocampus were demonstrated, which indicates that ischemic lesions may be associated with TGA. Level of Evidence: 2 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2017.

In this study, we report the clinical and genetic features of Chinese patients with X-linked lymphoproliferative syndrome (XLP). Male patients with fulminant infectious mononucleosis (FIM), Epstein-Barr virus (EBV)-associated hemophagocytic lymphohistiocytosis (HLH) or persistent EBV viremia were enrolled in this study. Direct sequencing was used to detect SH2D1A/XIAP gene mutations. The patients' clinical features were assessed by retrieval of data from medical records. Twenty-one male patients with FIM, EBV-associated HLH or persistent EBV viremia were evaluated. Four patients had SH2D1A mutations, and one patient had an XIAP mutation. All five of these patients had symptoms of HLH and EBV infection. Among the five patients, the youngest one was only 1 month old at onset. One patient exhibited hypogammaglobulinemia. Of four patients evaluated for immunological function, all exhibited reduced CD4/CD8 ratios. Three patients had rapid disease progression and died. One patient received haematopoietic stem cell transplantation and is well. The overall clinical phenotypes of Chinese patients with XLP matched previous reports. For patients with severe EBV-associated HLH, our results indicate the need to examine the possibility of XLP.

Glycogen synthase kinase-3 beta (GSK-3β) dysfunction may play an essential role in the pathogenesis of psychiatric, metabolic, neurodegenerative diseases, in which oxidative stress exists concurrently. Some studies have shown that GSK-3β activity is up-regulated under oxidative stress. This study evaluated how oxidative stress regulates GSK-3β activity in human embryonic kidney 293 (HEK293)/Tau cells treated with hydrogen peroxide (H₂O₂). Here, we show that H₂O₂ induced an obvious increase of GSK-3β activity. Surprisingly, H₂O₂ dramatically increased phosphorylation of GSK-3β at Ser9, an inactive form of GSK-3β,while there were no changes of phosphorylation of GSK-3β at Tyr216. Moreover, H₂O₂ led to a transient [Ca²⁺](i) elevation, and simultaneously increased the truncation of GSK-3β into two fragments of 40 kDa and 30 kDa, whereas inhibition of calpain decreased the truncation and recovered the activity of GSK-3β. Furthermore, tau was hyperphosphorylated at Ser396, Ser404, and Thr231, three most common GSK-3β targeted sites after 100 μM H₂O₂ administration in HEK293/Tau cells, whereas inhibition of calpain blocked the tau phosphorylation. In addition, we found that there were no obvious changes of Cyclin-dependent kinase 5 (CDK5) expression (responsible for tau phosphorylation) and of p35 cleavage, the regulatory subunit of CDK5 in H₂O₂-treated HEK293/Tau cells. In conclusion, Ca²⁺-dependent calpain activation leads to GSK-3β truncation, which counteracts the inhibitory effect of Ser9 phosphorylation, up-regulates GSK-3β activity, and phosphorylates tau in H₂O₂-treated HEK293/Tau cells.

Li C, Li Y, Wang X, Wang Z, Cai J, Wang L, Zhao Y, Song H, Meng X, Ning X, Xu C, Lin M, Li L & Geng J (2012) Histopathology 60, 953–963 Elevated expression of astrocyte elevated gene-1 (AEG-1) is correlated with cisplatin-based chemoresistance and shortened outcome in patients with stages III–IV serous ovarian carcinoma Aims: To correlate astrocyte elevated gene-1 (AEG-1) expression with the clinicopathological features and outcome of patients with stages III–IV ovarian serous carcinoma, and to clinically assess the involvement of AEG-1 in acquired cisplatin resistance. Methods and results: The frequency and intensity of immunohistochemical AEG-1 expression increased in a step-wise fashion from normal to chemosensitive to chemoresistant tissues. These observations were confirmed by Western blot analysis. AEG-1 expression level was correlated with lymph nodal metastasis, histological differentiation, residual tumour size and response to primary chemotherapy. Five-year progression-free survival (PFS) and overall survival (OS) rates were lower in the high-expression group than that in the low-expression group. AEG-1 overexpression was an independent but poor prognostic factor in the OS and PFS of these patients, as determined by multivariate Cox regression analysis. Multivariate logistic regression analysis revealed that the presence of cisplatin-based chemoresistance was significantly associated with expression level of AEG-1 and the degree of residual disease (P = 0.0001 and P = 0.0027, respectively). Conclusion: Our findings indicate that tumour AEG-1 overexpression is associated with poor prognosis and cisplatin resistance in advanced serous ovarian cancer.

A compact CPW-fed ultrawideband antenna with 3.9/5.5 GHz dual band-notched characteristics is presented in this article. The antenna consists of a cup-like radiating patch and a 50-Ω coplanar waveguide transmission line. The dual band-notched characteristics are obtained by etching a pair of L-shaped slots on the edge of ground plane and introducing two symmetrical L-shaped stubs on the radiating patch. Simulated and measured results show that the proposed antenna has a wide bandwidth from 2.5 to 11.0 GHz with stable gain and omnidirectional radiation pattern. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1047–1049, 2014

Introduction The aim of this study was to explore whether patients with chronic obstructive pulmonary disease (COPD) develop vasogenic cerebral edema, and whether this edema contributes to the COPD‐related disability. Methods Eighteen stable patients with COPD and 17 matched healthy volunteers were enrolled. Apparent diffusion coefficient (ADC) values were calculated by voxel‐based analysis using DTI‐Studio software based on diffusion tensor imaging. COPD‐related disability was calculated using activities of daily living (ADL) scale. Results In patients with COPD, ADC increased in the white matter fiber tracts including the bilateral anterior cingulum and posterior corpus callosum and in the white matter fibers connecting the bilateral insular cortices, sub‐lobar cortices, and pars triangularis cortices and the left rectus and olfactory gyrus. However, after further controlling for cigarette smoking, the difference in ADC values in the posterior corpus callosum between groups disappeared. Patients with COPD had significantly higher scores in ADL than that in controls. Moreover, ADL scores were positively correlated with the increased regional ADC values. Conclusion Vasogenic cerebral edema occurs in patients with COPD. Cigarette smoking may be a risk factor for COPD‐related vasogenic edema. Vasogenic cerebral edema may be related to the COPD‐related ADL impairment.

Development of rational therapeutic treatments of Alzheimer disease (AD) requires the elucidation of the etiopathogenic mechanisms of neurofibrillary degeneration and β-amyloidosis, the two hallmarks of this disease. Here we show, employing an adeno-associated virus serotype 1 (AAV1)-induced expression of the C-terminal fragment (I2CTF) of I2PP2A, also called SET, in rat brain, decrease in protein phosphatase 2A (PP2A) activity, abnormal hyperphosphorylation of tau, and neurodegeneration; littermates treated identically but with vector only, i.e., AAV1-enhanced green fluorescent protein (GFP), served as a control. Furthermore, there was an increase in the level of activated glycogen synthase kinase-3β and enhanced expression of intraneuronal Aβ in AAV1-I2CTF animals. Morris water maze behavioral test revealed that infection with AAV1-I2CTF induced spatial reference memory and memory consolidation deficits and a decrease in the brain level of pSer133-CREB. These findings suggest a novel etiopathogenic mechanism of AD, which is initiated by the cleavage of I2PP2A, producing I2CTF, and describe a novel disease-relevant nontransgenic animal model of AD.—Wang, X., Blanchard, J., Kohlbrenner, E., Clement, N., Linden, R. M., Radu, A., Grundke-Iqbal, I., Iqbal, K. The carboxy-terminal fragment of inhibitor-2 of protein phosphatase-2A induces Alzheimer disease pathology and cognitive impairment.

In this article, epoxy foams comprised of diglycidyl ether of bisphenol-A (DGEBA) based epoxy resin E31 and E51, polyamide resin, and water were prepared by microwave irradiation method. The structure and properties of epoxy foams were analyzed by FTIR, TGA, SEM, and DMA methods. The density and compressive performance of epoxy foams was also determined. The results indicated that the epoxy foams had excellent compressive performance and the preparation of epoxy foam by microwave irradiation was high efficiency and convenient. The composition has great effect on density, foam structure, dynamical mechanic performance, and thermal degradation behavior of epoxy foams. The epoxy foam with density from 0.08 g cm−3 to 1.05 g cm−3 can be obtained by varying ratio of E51 and E31 to control the viscosity of mixtures. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

The activity of protein phosphatase (PP)-2A and PP-1 decreased in the brains of Alzheimer's disease and inhibition of the phosphatases led to spatial memory deficit in rats. However, the molecular basis underlying memory impairment of the phosphatase inhibition is elusive. In the present study, we observed a selective inhibition of PP-2A and PP-1 with Calyculin A (CA) not only caused hyperphosphorylation of cytoskeletal proteins, but also impaired the transport of pEGFP-labeled neurofilament-M subunit in the axon-like processes of neuroblastoma N2a cells and resulted in accumulation of neurofilament in the cell bodies. To analyze the morphological alteration of the cells during inhibition of the phosphatases, we established a cell model showing steady outgrowth of axon-like cell processes and employed a stereological system to analyze the retraction of the processes. We found CA treatment inhibited outgrowth of the cell processes and prolonged treatment with CA caused retraction of the processes and meanwhile, the early neurodegenerative varicosities were also obvious in the CA-treated cells. We conclude suppression of PP-2A and PP-1 by CA not only damages intracellular transport but also leads to cell degeneration, which may serve as the functional and structural elements for the memory deficits induced by suppression of the phosphatases.

Indirect LIF detection was applied to the detection of four acidic diuretics separated by CZE. Semiconductor laser was employed to provide the stable excitation of 473 nm. With an optimized electrophoretic buffer system which contained 5 mM of triethylamine, 0.1 microM of fluorescein, and 5% of n-butanol, fast separation of four diuretics (ethacrynic acid, chlorthalidone, bendroflumethiazide, and bumetanide) can be performed within 3 min with the detection limits of 0.2-2 microg/mL. The impacts of buffer components including the concentrations of the electrolytes, fluorescence probe, and the organic additives were demonstrated. The method was applied for the detection of diuretics in urine. As an alternative way for the fast analysis of diuretics, this indirect detection method provided the technical support for future microchip performances, in which diuretics may be detected in the microchip by the common LIF detector without derivatization.

Abnormal phosphorylation of microtubule-associated protein tau plays a critical role in Alzheimer's disease (AD), together with a distinct decrease of energy metabolism in the affected brain regions. To explore the effect of acute energy crisis on tau phosphorylation and the underlying mechanisms, we incubated rat brain slices in artificial cerebrospinal fluid (aCSF) at 37 degrees C with or without an oxygen supply, or in aCSF with low glucose concentrations. Then, the levels of total, phosphorylated and unphosphorylated tau, as well as the activities and levels of protein phosphatase (PP)-1, PP-2A, glycogen synthase kinase 3 (GSK-3), extracellular signal-regulated protein kinase (ERK) and C-jun amino terminal kinase (JNK), were measured. It was found, unexpectedly, that tau was significantly dephosphorylated at Ser396/Ser404 (PHF-1), Ser422 (R145), Ser199/Ser202 (Tau-1), Thr181 (AT270), Ser202/Thr205 (AT8) and Thr231 (AT180) by acute anoxia for 30 min or 120 min. The activity of PP-2A and the level of dephosphorylated PP-2A catalytic subunit at tyrosine 307 (Tyr307) were simultaneously increased. The active forms of ERK1/2 and JNK1/2 were decreased under anoxic incubation. The PP-2A inhibitor, okadaic acid (OA, 0.75 microm), completely prevented tau from acute anoxia-induced dephosphorylation and restored the active forms of ERK1/2 and JNK1/2 to the control level. The activities and protein levels of GSK-3 and PP-1 showed no change during acute anoxia. These data suggest that acute anoxia induces tau dephosphorylation, and that PP-2A may play a key role in tau dephosphorylation induced by acute anoxia.

In the current work, a simple, rapid, accurate and inexpensive method was developed for the determination of acetone in human blood. The proposed method is based on derivatization with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA), followed by headspace liquid-phase microextraction (HS-LPME) and gas chromatography/mass spectrometry (GC/MS). In the present method, acetone in blood samples was derivatized with PFBHA and acetone oxime formed in several seconds. The formed oxime was enriched by HS-LPME using the organic solvent film (OSF) formed in a microsyringe barrel as extraction interface. Finally, the enriched oxime was analyzed by GC/MS in electron ionization (EI) mode. HS-LPME parameters including solvent, syringe plunger withdrawal rate, sampling volume, and extraction cycle were optimized and the method reproducibility, linearity, recovery and detection limit were studied. The proposed method was applied to determination of acetone in diabetes blood and normal blood. It has been shown that derivatization with HS-LPME and GC/MS is an alternative method for determination of the diabetes biomarker, acetone, in blood samples.