5,653 research outputs found

    A fully integrated paperfluidic molecular diagnostic chip for the extraction, amplification, and detection of nucleic acids from clinical samples

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    Paper diagnostics have successfully been employed to detect the presence of antigens or small molecules in clinical samples through immunoassays; however, the detection of many disease targets relies on the much higher sensitivity and specificity achieved via nucleic acid amplification tests (NAAT). The steps involved in NAAT have recently begun to be explored in paper matrices, and our group, among others, has reported on paper-based extraction, amplification, and detection of DNA and RNA targets. Here, we integrate these paper-based NAAT steps into a single paperfluidic chip in a modular, foldable system that allows for fully integrated fluidic handling from sample to result. We showcase the functionality of the chip by combining nucleic acid isolation, isothermal amplification, and lateral flow detection of human papillomavirus (HPV) 16 DNA directly from crude cervical specimens in less than 1 hour for rapid, early detection of cervical cancer. The chip is made entirely of paper and adhesive sheets, making it low-cost, portable, and disposable, and offering the potential for a point-of-care molecular diagnostic platform even in remote and resource-limited settings.U54 EB015403 - NIBIB NIH HHS; U54 EB015408 - NIBIB NIH HHS; U54-EB015403-S1 - NIBIB NIH HH

    The Effects of Rhodiola Crenulata Extract on Proliferation and Differentiation in Glioblastoma Multiforme

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    Purpose: Purpose of the study was to evaluate the effects of rhodiola crenulata plant extract on glioblastoma in vitro. Methods: U-87MG glioblastoma multiforme cell line was utilized for evaluation in this study. Cells were treated with 100ug/ml or 200ug/ml of rhodiola crenulata and compared to ethanol vehicle control. Proliferation was measured at 24, 48, 72, and 96 hours after treatment utilizing an MTS proliferation assay. To further assess proliferation a clonogenicity assay was conducted. These cells were treated with ethanol vehicle control, 100ug/ml of rhodiola, radiation, or combined rhodiola/radiation treatment. To evaluate differentiation the expression of glial fibrillary acidic protein (GFAP), a protein marker of differentiation, was assessed with immunocytochemistry. Results: Effects on proliferation were initially noted at 48hours after treatment and observed through the 96-hour period. The effects on proliferation were noted in both treatment groups. At 96-hours after treatment significant difference was noted between the 100ug/ml of rhodiola and control group (p=0.0065) and significant difference noted between the 200ug/ml of rhodiola and control group (p=0.0006). Cell clonogenicity was reduced in the cells treated with 100ug/ml of rhodiola. The decreased number of colonies was significant when comparing the radiation treated cells with 100ug/ml rhodiola treated cells (p=0.0030). GFAP was overexpressed in the rhodiola treatment group when compared to expression in the control group (Figure 1). Conclusion: Rhodiola crenulata extract effectively decreases proliferation and increases differentiation of glioblastoma cells in vitro. Further work is required to fully understand the extent and full effects rhodiola crenulata has glioblastoma cells

    Genetic study of congenital bile-duct dilatation identifies de novo and inherited variants in functionally related genes

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    Background: Congenital dilatation of the bile-duct (CDD) is a rare, mostly sporadic, disorder that results in bile retention with severe associated complications. CDD affects mainly Asians. To our knowledge, no genetic study has ever been conducted. Methods: We aim to identify genetic risk factors by a “trio-based” exome-sequencing approach, whereby 31 CDD probands and their unaffected parents were exome-sequenced. Seven-hundred controls from the local population were used to detect gene-sets significantly enriched with rare variants in CDD patients. Results: Twenty-one predicted damaging de novo variants (DNVs; 4 protein truncating and 17 missense) were identified in several evolutionarily constrained genes (p < 0.01). Six genes carrying DNVs were associated with human developmental disorders involving epithelial, connective or bone morphologies (PXDN, RTEL1, ANKRD11, MAP2K1, CYLD, ACAN) and four linked with cholangio- and hepatocellular carcinomas (PIK3CA, TLN1 CYLD, MAP2K1). Importantly, CDD patients have an excess of DNVs in cancer-related genes (p < 0.025). Thirteen genes were recurrently mutated at different sites, forming compound heterozygotes or functionally related complexes within patients. Conclusions: Our data supports a strong genetic basis for CDD and show that CDD is not only genetically heterogeneous but also non-monogenic, requiring mutations in more than one genes for the disease to develop. The data is consistent with the rarity and sporadic presentation of CDD

    In Vivo Evaluation of a Biomimetic Polymer-Doxorubicin Conjugate for Cancer Therapy

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    This poster will describe a novel polymer pro-drug platform designed for conjugation and delivery of chemotherapeutics. Specifically, polymer pro-drugs were prepared from functional polymer zwitterions and doxorubicin (DOX), and evaluated in vivo to assess toxicological, pharmacokinetic and therapeutic properties. The biocompatible polymer scaffold (PolyMPC) consists of zwitterionic phosphorylcholine pendent groups, which mimic the natural hydrophilic moieties of phospholipids in cell membranes, and hydrazone linkages that allow for pH-triggered release of DOX. PolyMPC-DOX pro-drugs were isolated as dry solids using a facile strategy that allows for precise control of molecular weight and DOX incorporation. In vivo toxicity of PolyMPC and PolyMPC-DOX was assessed in a murine model. The maximum tolerated dose of the pro-drug was five times greater than that of free DOX, while PolyMPC alone exhibited no toxicity even at a dose of 800 mg/kg. A pharmacokinetic study in tumor-bearing mice demonstrated a significant increase in circulation half-life of conjugated DOX (t1/2=2 hours) compared to free DOX (t1/2=15 minutes), with conjugated DOX detectable in blood serum for longer than 24 hours. This pronounced enhancement in circulation time was attributed to the macromolecular scaffold, which precludes rapid renal clearance compared to native DOX. Examination of mice given PolyMPC-DOX five days after injection in the PK study showed a three-fold increase of drug accumulated in tumor tissue compared to that of mice treated with free DOX and drug accumulation in off-target organs was reduced for mice given DOX conjugate. The therapeutic efficacy of the PolyMPC-DOX conjugates was then assessed in an orthotopic murine breast cancer model. The treatment group given PolyMPC-DOX exhibited a two-fold increase in overall survival and a significant reduction in average tumor volume compared to the free DOX and saline control groups. A study evaluating the therapeutic efficacy of PolyMPC-DOX in a human ovarian xenograft tumor model is ongoing

    Dispersion enhancement and damping by buoyancy driven flows in 2D networks of capillaries

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    The influence of a small relative density difference on the displacement of two miscible liquids is studied experimentally in transparent 2D networks of micro channels. Both stable displacements in which the denser fluid enters at the bottom of the cell and displaces the lighter one and unstable displacements in which the lighter fluid is injected at the bottom and displaces the denser one are realized. Except at the lowest mean flow velocity U, the average C(x,t)C(x,t) of the relative concentration satisfies a convection-dispersion equation. The dispersion coefficient is studied as function of the relative magnitude of fluid velocity and of the velocity of buoyancy driven fluid motion. A model is suggested and its applicability to previous results obtained in 3D media is discussed

    Chinese family with diffuse oesophageal leiomyomatosis: A new COL4A5/COL4A6 deletion and a case of gonosomal mosaicism

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    © 2015 Liu et al. Background: Diffuse oesophageal leiomyomatosis (DOL) is a rare disorder characterized by tumorous overgrowth of the muscular wall of the oesophagus. DOL is present in 5 % of Alport syndrome (AS) patients. AS is a rare hereditary disease that involves varying degrees of hearing impairment, ocular changes and progressive glomerulonephritis leading to renal failure. In DOL-AS patients, the genetic defect consists of a deletion involving the COL4A5 and COL4A6 genes on the X chromosome. Case presentation: We report a two-generation family (4 individuals; parents and two children, one male and one female) with two members (mother and son) affected with oesophageal leiomyomatosis. Signs of potential renal failure, which characterizes AS, were only apparent in the index patient (son) 2 years and three months after the initial diagnosis of DOL. Blood DNA from the four family members were submitted to exome sequencing and array genotyping to perform a genome wide screening for disease causal single nucleotide (SN) and copy number (CN) variations. Analyses revealed a new 40kb deletion encompassing from intron 2 of COL4A5 to intron 1 of COL4A6 at Xq22.3. The breakpoints were also identified. Possible confounding pathogenic exonic variants in genes known to be involved in other extracellular matrices disorders were also shared by the two affected individuals. Meticulous analysis of the maternal DNA revealed a case of gonosomal mosaicism. Conclusions: This is the first report of gonadosomal mosaicism associated to DOL-AS.published_or_final_versio

    Time Course and Cellular Localization of SARS-CoV Nucleoprotein and RNA in Lungs from Fatal Cases of SARS

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    BACKGROUND: Cellular localization of severe acute respiratory syndrome coronavirus (SARS-CoV) in the lungs of patients with SARS is important in confirming the etiological association of the virus with disease as well as in understanding the pathogenesis of the disease. To our knowledge, there have been no comprehensive studies investigating viral infection at the cellular level in humans. METHODS AND FINDINGS: We collected the largest series of fatal cases of SARS with autopsy material to date by merging the pathological material from two regions involved in the 2003 worldwide SARS outbreak in Hong Kong, China, and Toronto, Canada. We developed a monoclonal antibody against the SARS-CoV nucleoprotein and used it together with in situ hybridization (ISH) to analyze the autopsy lung tissues of 32 patients with SARS from Hong Kong and Toronto. We compared the results of these assays with the pulmonary pathologies and the clinical course of illness for each patient. SARS-CoV nucleoprotein and RNA were detected by immunohistochemistry and ISH, respectively, primarily in alveolar pneumocytes and, less frequently, in macrophages. Such localization was detected in four of the seven patients who died within two weeks of illness onset, and in none of the 25 patients who died later than two weeks after symptom onset. CONCLUSIONS: The pulmonary alveolar epithelium is the chief target of SARS-CoV, with macrophages infected subsequently. Viral replication appears to be limited to the first two weeks after symptom onset, with little evidence of continued widespread replication after this period. If antiviral therapy is considered for future treatment, it should be focused on this two-week period of acute clinical disease
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