81 research outputs found

    Peptide mimics of a conserved H5N1 avian influenza virus neutralization site

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    A panel of 52 murine monoclonal antibodies was found to recognize antigenic determinants that had been conserved among till major genetic subgroups of the I ON I avian influenza virus prevalent since 1997. We screened a phage display library for peptides recognized by one such antibody (8H5). We analysed the specificity of 8H5 for reactive peptides presented as fusion proteins of HBc (hepatitis B core protein) and HEV (hepatitis E virus) structural protein, p239. This was then related to the specificity of the native HA (haemagglutinin) molecule by virtue of the capacity of fusion proteins to compete for 8H5 binding with different strains of H5N1 virus and the reactivity of antisera generated against fusion proteins to bind native HA molecules, and to inhibit haemagglutination and arrest infection by the virus. Nine reactive peptides of different amino acid sequences were identified, six of which were also reactive with the antibody in association with HBc and four were in association with p239. Binding occurred with the dimeric form of the four p239-fusion proteins and one of the HBc-fusion proteins, but not with the monomeric form. The HBc-fusion proteins blocked 8H5 binding with four strains of H5N1 influenza virus. Mouse antisera generated against fusion proteins bound to HA molecules, but did not inhibit haemagglutination or arrest H5N1 infection. Our findings indicate that 8H5 recognizes discontinuous sites presented by secondary and possibly higher structural orders ol'the peptides in spatially favourable positions for binding with the antibody, and that the peptides partially mimic the native 8H5 epitopes oil file H5N1 virus.Science and Technology Foundation of Fujian Province [2008Y0059, F2006BA101B06]; Key Project of Chinese Ministry of Education [1081157]; Foundation front Ministry of Science and Technology [2005DC105006

    Large expert-curated database for benchmarking document similarity detection in biomedical literature search

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    Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

    Risk assessment scales to predict risk of lower extremity deep vein thrombosis among multiple trauma patients: a prospective cohort study

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    Abstract Background Deep vein thrombosis (DVT) is a common complication in orthopedic patients. Previous studies have focused on major orthopedic surgery.There are few studies with multiple trauma. We aimed to describe the prevalence of DVT and compare the predictive power of the different risk assessment scales in patients with multiple trauma. Methods This prospective cohort study involved multiple trauma patients admitted to our hospital between October 2021 and December 2022. Data were prospectively collected for thrombotic risk assessments using the Risk Assessment Profile for thromboembolism(RAPT), the DVT risk assessment score (DRAS), and the Trauma Embolic Scoring System (TESS), respectively. The receiver operation characteristic (ROC) curve and the area under the curve (AUC) were evaluated to compare the predictive power. The whole leg duplex ultrasound of both lower extremities Doppler ultrasound was used to determine DVT incidence. Results A total of 210 patients were included, and the incidence of DVT was 26.19%. Distal DVT accounted for 87.27%; postoperative DVT, 72.73%; and bilateral lower extremity thrombosis, 30.91%. There were significant differences in age, education degree, pelvic fracture, surgery, ISS, D-dimer level, length of hospital stay and ICU stay between the thrombosis group and the non-thrombosis group. The AUCs for RAPT, DRAS, and TESS were 0.737, 0.710, and 0.683, respectively. There were no significant differences between the three ROC curves. Conclusions The incidence of DVT was relatively high during hospitalization. We prospectively validated the tests to predict risk of DVT among patients with multiple trauma to help trauma surgeons in the clinical administration of DVT prophylaxis

    The association between ballroom dance training and empathic concern: Behavioral and brain evidence

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    Dance is unique in that it is a sport and an art simultaneously. Beyond improving sensorimotor functions, dance training could benefit high-level emotional and cognitive functions. Duo dances also confer the possibility for dancers to develop the abilities to recognize, understand, and share the thoughts and feelings of their dance partners during the long-term dance training. To test this possibility, we collected high-resolution structural and resting-state functional magnetic resonance imaging (MRI) data from 43 expert-level ballroom dancers (a model of long-term exposure to duo dance training) and 40 age-matched and sex-matched nondancers, and measured their empathic ability using a self-report trait empathy scale. We found that ballroom dancers showed higher scores of empathic concern (EC) than controls. The EC scores were positively correlated with years with dance partners but negatively correlated with the number of dance partners for ballroom dancers. These behavioral results were supported by the structural and functional MRI data. Structurally, we observed that the gray matter volumes in the subgenual anterior cingulate cortex (ACC) and EC scores were positively correlated. Functionally, the connectivity between ACC and occipital gyrus was positively correlated with both EC scores and years with dance partners. In addition, the relationship between years with dance partners and EC scores was indirect-only mediated by the ACC-occipital gyrus functional connectivity. Therefore, our findings provided solid evidence for the close link between long-term ballroom dance training and empathy, which deepens our understanding of the neural mechanisms underlying this phenomenon

    Ginkgo biloba extract-loaded PLGA microcapsules generated from microfluidics for Alzheimer's disease treatment

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    Boosting the birth rate of new neurons in the adult hippocampus is a possible treatment method for the management of Alzheimer's disease (AD). Recent studies have revealed that Ginkgo biloba extract (GBE) can act as a neuroprotective agent to prevent memory loss in a variety of neurodegenerative illnesses. However, the low bioavailability and short half-life of active components in vivo limit their application. Here, we describe a class of microcapsules (MPs) for sustained GBE delivery that have gelatin methacrylate (GelMa) cores and poly(L-lactide-co-glycolide) (PLGA) shells. The encapsulated GBE was slowly released from the solidified MPs during degradation of the polymer. In addition, the MPs showed good biocompatibility in cell experiments. When GelMa-PLGA MPs containing GBE were applied to APP/PS1 mice, amyloid deposition in the mouse brain was reduced, and cognitive impairment was improved. These results indicate that GBE-encapsulated MPs have potential clinical value in treating AD and other neurodegenerative diseases

    Attenuating Tumour Angiogenesis: A Preventive Role of Metformin against Breast Cancer

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    Metformin is one of the most widely prescribed antidiabetics for type 2 diabetes. A critical role of metformin against tumorigenesis has recently been implicated, although several studies also reported the lack of anticancer property of the antidiabetics. Given the controversies regarding the potential role of metformin against tumour progression, the effect of metformin against breast, cervical, and ovarian tumour cell lines was examined followed by in vivo assessment of metformin on tumour growth using xenograft breast cancer models. Significant inhibitory impact of metformin was observed in MCF-7, HeLa, and SKOV-3 cells, suggesting an antiproliferative property of metformin against breast, cervical, and ovarian tumour cells, respectively, with the breast tumour cells, MCF-7, being the most responsive. In vivo assessment was subsequently carried out, where mice with breast tumours were treated with metformin (20 mg/kg body weight) or sterile PBS solution for 15 consecutive days. No inhibition of breast tumour progression was detected. However, tumour necrosis was significantly increased in the metformin-treated group, accompanied by decreased capillary formation within the tumours. Thus, despite the lack of short-term benefit of metformin against tumour progression, a preventive role of metformin against breast cancer was implicated, which is at partially attributable to the attenuation of tumour angiogenesis

    Mutational Spectrum Analysis of Seven Genes Associated with Thyroid Dyshormonogenesis

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    Objective. Thyroid dyshormonogenesis (DH) is a genetically heterogeneous inherited disorder caused by thyroid hormone synthesis abnormalities. This study aims at comprehensively characterizing the mutation spectrum in Chinese patients with DH. Subjects and Methods. We utilized next-generation sequencing to screen for mutations in seven DH-associated genes (TPO, DUOX2, TG, DUOXA2, SLC26A4, SLC5A5, and IYD) in 21 Chinese Han patients with DH from Xinjiang Province. Results. Twenty-eight rare nonpolymorphic variants were found in 19 patients (90.5%), including 19, 5, 3, and 1 variants in DUOX2, TG, DUOXA2, and SLC26A4, respectively. Thirteen (62%) patients carried monogenic mutations, and six (28.5%) carried oligogenic mutations. Fifteen (71%) patients carried 2 or more DUOX2 (14) or DUOXA2 (1) variants. The genetic basis of DH in nine (43%) patients harboring biallelic or triallelic pathogenic variants was resolved. Seventeen patients (81%) carried DUOX2 mutations, most commonly p.R1110Q or p.K530X. No correlations were found between DUOX2 mutation types or numbers and clinical phenotypes. Conclusions. DUOX2 mutations were the most predominant genetic alterations of DH in the study cohort. Oligogenicity may explain the genetic basis of disease in many DH patients. Functional studies and further clinical studies with larger DH patient cohorts are needed to validate the roles of the mutations identified in this study

    Supramolecular co-assembly of self-adjuvanting nanofibrious peptide hydrogel enhances cancer vaccination by activating MyD88-dependent NF-κB signaling pathway without inflammation

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    Peptide vaccine targeting tumor-specific antigens is a promising cancer treatment regimen. However, peptide vaccines are commonly low-immunogenic, leading to suboptimal antitumor T-cell responses. Current peptide vaccination approaches are challenged by the variability of peptide physicochemical characters and vaccine formulations, flexibility, and the broad feasibility. Here, the supramolecular co-assembly of antigen epitope-conjugated peptides (ECPs) targeting CD8 or CD4 T-cell receptors was used to engineer a nanofibrious hydrogel vaccine platform. This approach provided precise and tunable loading of peptide antigens in nanofibers, which notably increased the antigen uptake, cross-presentation, and activation of dendritic cells (DCs). Immunization in mice indicated that the co-assembled peptide hydrogel did not induce local inflammation responses and elicited significantly promoted T-cell immunity by activating the MyD88-dependent NF-κB signaling pathway in DCs. Vaccination of mice using co-assembled peptide vaccine stimulated both enhanced CD8 and CD4 T cells against EG.7-OVA tumors without additional immunoadjuvants or delivery systems, and resulted in a more remarkable cancer immunotherapy efficacy, compared with free peptide vaccine or aluminum-adjuvanted peptide formulation. Altogether, peptide co-assembly demonstrated by three independent pairs of ECPs is a facile, customizable, and chemically defined approach for co-delivering peptide antigens in self-adjuvanting hydrogel vaccines that could induce stronger anticancer T-cell responses
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