245 research outputs found

    A plasmonic nanosensor with inverse sensitivity for circulating cell-free DNA quantification

    Get PDF
    A plasmonic nanosensor (using gold nanorods) with inverse sensitivity is presented for circulating cell-free DNA quantification. The inverse sensitivity (i.e. the lower the analyte concentration, the higher the response intensity) is achieved by the unusual DNA concentration-dependent gold nanorod aggregation. This assay method can adjust the dynamic range by controlling the concentration of nanoparticles in solution. Graphical abstract: A plasmonic nanosensor with inverse sensitivity for circulating cell-free DNA quantificatio

    Intervention effects of Ganoderma lucidum spores on epileptiform discharge hippocampal neurons and expression of Neurotrophin-4 and N-Cadherin

    Get PDF
    Epilepsy can cause cerebral transient dysfunctions. Ganoderma lucidum spores (GLS), a traditional Chinese medicinal herb, has shown some antiepileptic effects in our previous studies. This was the first study of the effects of GLS on cultured primary hippocampal neurons, treated with Mg2+ free medium. This in vitro model of epileptiform discharge hippocampal neurons allowed us to investigate the anti-epileptic effects and mechanism of GLS activity. Primary hippocampal neurons from <1 day old rats were cultured and their morphologies observed under fluorescence microscope. Neurons were confirmed by immunofluorescent staining of neuron specific enolase (NSE). Sterile method for GLS generation was investigated and serial dilutions of GLS were used to test the maximum non-toxic concentration of GLS on hippocampal neurons. The optimized concentration of GLS of 0.122 mg/ml was identified and used for subsequent analysis. Using the in vitro model, hippocampal neurons were divided into 4 groups for subsequent treatment i) control, ii) model (incubated with Mg2+ free medium for 3 hours), iii) GLS group I (incubated with Mg2+ free medium containing GLS for 3 hours and replaced with normal medium and incubated for 6 hours) and iv) GLS group II (neurons incubated with Mg2+ free medium for 3 hours then replaced with a normal medium containing GLS for 6 hours). Neurotrophin-4 and N-Cadherin protein expression were detected using Western blot. The results showed that the number of normal hippocampal neurons increased and the morphologies of hippocampal neurons were well preserved after GLS treatment. Furthermore, the expression of neurotrophin-4 was significantly increased while the expression of N-Cadherin was decreased in the GLS treated group compared with the model group. This data indicates that GLS may protect hippocampal neurons by promoting neurotrophin-4 expression and inhibiting N-Cadherin expression

    All-Electrical Skyrmionic Bits in a Chiral Magnetic Tunnel Junction

    Full text link
    Topological spin textures such as magnetic skyrmions hold considerable promise as robust, nanometre-scale, mobile bits for sustainable computing. A longstanding roadblock to unleashing their potential is the absence of a device enabling deterministic electrical readout of individual spin textures. Here we present the wafer-scale realization of a nanoscale chiral magnetic tunnel junction (MTJ) hosting a single, ambient skyrmion. Using a suite of electrical and multi-modal imaging techniques, we show that the MTJ nucleates skyrmions of fixed polarity, whose large readout signal - 20-70% relative to uniform states - corresponds directly to skyrmion size. Further, the MTJ exploits complementary mechanisms to stabilize distinctly sized skyrmions at zero field, thereby realizing three nonvolatile electrical states. Crucially, it can write and delete skyrmions using current densities 1,000 times lower than state-of-the-art. These results provide a platform to incorporate readout and manipulation of skyrmionic bits across myriad device architectures, and a springboard to harness chiral spin textures for multi-bit memory and unconventional computing.Comment: 8 pages, 5 figure

    Augmenter of liver regeneration ameliorates renal fibrosis in rats with obstructive nephropathy

    Get PDF
    Synopsis Renal fibrosis is a hallmark in CKD (chronic kidney disease) and is strongly correlated to the deterioration of renal function that is characterized by tubulointerstitial fibrosis, tubular atrophy, glomerulosclerosis and disruption of the normal architecture of the kidney. ALR (augmenter of liver regeneration) is a growth factor with biological functions similar to those of HGF (hepatocyte growth factor). In this study, our results indicate that endogenous ALR is involved in the pathological progression of renal fibrosis in UUO (unilateral ureteral obstruction) rat model. Moreover, we find that administration of rhALR (recombinant human ALR) significantly alleviates renal interstitial fibrosis and reduces renal-fibrosis-related proteins in UUO rats. Further investigation reveals that rhALR suppresses the up-regulated expression of TGF-β1 (transforming growth factor β1) induced by UUO operation in the obstructed kidney, and inhibits Smad2 and Smad3 phosphorylation activated by the UUO-induced injury in the animal model. Therefore we suggest that ALR is involved in the progression of renal fibrosis and administration of rhALR protects the kidney against renal fibrosis by inhibition of TGF-β/Smad activity

    Factors determining the survival of nasopharyngeal carcinoma with lung metastasis alone: does combined modality treatment benefit?

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Nasopharyngeal carcinoma (NPC) with lung metastasis alone has been reported as a relatively favorable prognostic group, and combined modality treatment might be indicated for selected cases. However, the prognostic factors determining survival of this group and the indication of combined therapy have not been thoroughly studied.</p> <p>Methods</p> <p>We retrospectively reviewed 246 patients of NPC with lung metastasis(es) alone presented at diagnosis or as the first failure after primary treatment from 1993 to 2008 in an academic tertiary hospital. Univariate and multivariate survival analyses of post-metastasis survival (PMS) and overall survival (OS) were carried out to determine the prognostic factors.</p> <p>Results</p> <p>The 3-year, 5-year, and 10-year of PMS and OS for the whole cohort were 34.3%, 17.0%, 8.6% and 67.8%, 45.4%, 18.5%, respectively. The median PMS (45.6 months <it>vs</it>. 23.7 months) and OS (73.7 months <it>vs</it>. 46.2 months) of patients treated with combined therapy was significantly longer than that of those treated with chemotherapy alone (<it>P </it>< 0.001). Age, disease-free interval (DFI) and treatment modality were evaluated as independent prognostic factors of OS, while only age and treatment modality retain their independent significance in PMS analysis. In stratified survival analysis, compared to chemotherapy alone, combined therapy could benefit the patients with DFI > 1 year, but not those with DFI ≤ 1 year.</p> <p>Conclusions</p> <p>Age ≤ 45 years, DFI > 1 year, and the combined therapy were good prognostic factors for NPC patients with lung metastasis(es) alone. The combination of local therapy and the basic chemotherapy should be considered for these patients with DFI > 1 year.</p

    Dramatic Co-Activation of WWOX/WOX1 with CREB and NF-κB in Delayed Loss of Small Dorsal Root Ganglion Neurons upon Sciatic Nerve Transection in Rats

    Get PDF
    BACKGROUND:Tumor suppressor WOX1 (also named WWOX or FOR) is known to participate in neuronal apoptosis in vivo. Here, we investigated the functional role of WOX1 and transcription factors in the delayed loss of axotomized neurons in dorsal root ganglia (DRG) in rats. METHODOLOGY/PRINCIPAL FINDINGS:Sciatic nerve transection in rats rapidly induced JNK1 activation and upregulation of mRNA and protein expression of WOX1 in the injured DRG neurons in 30 min. Accumulation of p-WOX1, p-JNK1, p-CREB, p-c-Jun, NF-kappaB and ATF3 in the nuclei of injured neurons took place within hours or the first week of injury. At the second month, dramatic nuclear accumulation of WOX1 with CREB (>65% neurons) and NF-kappaB (40-65%) occurred essentially in small DRG neurons, followed by apoptosis at later months. WOX1 physically interacted with CREB most strongly in the nuclei as determined by FRET analysis. Immunoelectron microscopy revealed the complex formation of p-WOX1 with p-CREB and p-c-Jun in vivo. WOX1 blocked the prosurvival CREB-, CRE-, and AP-1-mediated promoter activation in vitro. In contrast, WOX1 enhanced promoter activation governed by c-Jun, Elk-1 and NF-kappaB. WOX1 directly activated NF-kappaB-regulated promoter via its WW domains. Smad4 and p53 were not involved in the delayed loss of small DRG neurons. CONCLUSIONS/SIGNIFICANCE:Rapid activation of JNK1 and WOX1 during the acute phase of injury is critical in determining neuronal survival or death, as both proteins functionally antagonize. In the chronic phase, concurrent activation of WOX1, CREB, and NF-kappaB occurs in small neurons just prior to apoptosis. Likely in vivo interactions are: 1) WOX1 inhibits the neuroprotective CREB, which leads to eventual neuronal death, and 2) WOX1 enhances NF-kappaB promoter activation (which turns to be proapoptotic). Evidently, WOX1 is the potential target for drug intervention in mitigating symptoms associated with neuronal injury

    Demographic and Clinical Features and Prescribing Patterns of Psychotropic Medications in Patients with the Melancholic Subtype of Major Depressive Disorder in China

    Get PDF
    BACKGROUND: Little has been known about the demographic and clinical features of the melancholic subtype of major depressive disorder (MDD) in Chinese patients. This study examined the frequency of melancholia in Chinese MDD patients and explored its demographic and clinical correlates and prescribing patterns of psychotropic drugs. METHODS: A consecutively collected sample of 1,178 patients with MDD were examined in 13 psychiatric hospitals or psychiatric units of general hospitals in China nationwide. The cross-sectional data of patients' demographic and clinical characteristics and prescriptions of psychotropic drugs were recorded using a standardized protocol and data collection procedure. The diagnosis of the melancholic subtype was established using the Mini International Neuropsychiatric Interview (MINI). Medications ascertained included antidepressants, mood stabilizers, antipsychotics and benzodiazepines. RESULTS: Six hundred and twenty nine (53.4%) of the 1,178 patients fulfilled criteria for melancholia. In multiple logistic regression analyses, compared to non-melancholic counterparts, melancholic MDD patients were more likely to be male and receive benzodiazepines, had more frequent suicide ideations and attempts and seasonal depressive episodes, while they were less likely to be employed and receive antidepressants and had less family history of psychiatric disorders and lifetime depressive episodes. CONCLUSIONS: The demographic and clinical features of melancholic MDD in Chinese patients were not entirely consistent with those found in Western populations. Compared to non-melancholic MDD patients, melancholic patients presented with different demographic and clinical features, which have implications for treatment decisions

    A global view of the OCA2-HERC2 region and pigmentation

    Get PDF
    Mutations in the gene OCA2 are responsible for oculocutaneous albinism type 2, but polymorphisms in and around OCA2 have also been associated with normal pigment variation. In Europeans, three haplotypes in the region have been shown to be associated with eye pigmentation and a missense SNP (rs1800407) has been associated with green/hazel eyes (Branicki et al. in Ann Hum Genet 73:160–170, 2009). In addition, a missense mutation (rs1800414) is a candidate for light skin pigmentation in East Asia (Yuasa et al. in Biochem Genet 45:535–542, 2007; Anno et al. in Int J Biol Sci 4, 2008). We have genotyped 3,432 individuals from 72 populations for 21 SNPs in the OCA2-HERC2 region including those previously associated with eye or skin pigmentation. We report that the blue-eye associated alleles at all three haplotypes were found at high frequencies in Europe; however, one is restricted to Europe and surrounding regions, while the other two are found at moderate to high frequencies throughout the world. We also observed that the derived allele of rs1800414 is essentially limited to East Asia where it is found at high frequencies. Long-range haplotype tests provide evidence of selection for the blue-eye allele at the three haplotyped systems but not for the green/hazel eye SNP allele. We also saw evidence of selection at the derived allele of rs1800414 in East Asia. Our data suggest that the haplotype restricted to Europe is the strongest marker for blue eyes globally and add further inferential evidence that the derived allele of rs1800414 is an East Asian skin pigmentation allele

    Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

    Get PDF
    BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London
    corecore