120 research outputs found

    An in situ study on the coalescence of monolayer-protected Au-Ag nanoparticle deposits upon heating

    Get PDF
    The structural evolution of thiolate-protected nanoparticles of gold, silver, and their alloys with various Au/Ag ratios (3:1, 1:1, and 1:3) upon heating was investigated by means of in situ synchrotron radiation X-ray diffraction. The relationships between the coalescence and composition of nanoparticles, as well as the surfactant reactions, were clarified. Experimental results show that there existed a critical temperature ranging from 120°C to 164°C, above which the tiny broad X-ray diffraction peaks became sharp and strong due to particle coalescence. The coalescence temperatures for alloy nanoparticle deposits were clearly lower than those for pure metals, which can be ascribed to the rivalry between the thermodynamic effect due to alloying and the interactions between surface-assembled layers and the surface atoms of the nanoparticles. The strong affinity of thiolates to Ag and thus complex interactions give rise to a greater energy barrier for the coalescence of nanoparticles into the bulk and subsequent high coalescence temperature. The influences of particle coalescence on the optical and electrical properties of the nanoparticle deposits were also explored

    Terpenoids from the Octocorals Menella sp. (Plexauridae) and Lobophytum crassum (Alcyonacea)

    Get PDF
    A new germacrane-type sesquiterpenoid, menelloide E (1), and a new cembrane-type diterpenoid, lobocrassin F (2), were isolated from the octocorals Menella sp. and Lobophytum crassum, respectively. The structures of terpenoids 1 and 2 were determined by spectroscopic and chemical methods and compound 2 was found to display a significant inhibitory effect on the release of elastase by human neutrophils

    Invasive fungal infection among hematopoietic stem cell transplantation patients with mechanical ventilation in the intensive care unit

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Invasive fungal infection (IFI) is associated with high morbidity and high mortality in hematopoietic stem cell transplantation (HSCT) patientsThe purpose of this study was to assess the characteristics and outcomes of HSCT patients with IFIs who are undergoing MV at a single institution in Taiwan.</p> <p>Methods</p> <p>We performed an observational retrospective analysis of IFIs in HSCT patients undergoing mechanical ventilation (MV) in an intensive care unit (ICU) from the year 2000 to 2009. The characteristics of these HSCT patients and risk factors related to IFIs were evaluated. The status of discharge, length of ICU stay, date of death and cause of death were also recorded.</p> <p>Results</p> <p>There were 326 HSCT patients at the Linkou Chang-Gung Memorial Hospital (Taipei, Taiwan) during the study period. Sixty of these patients (18%) were transferred to the ICU and placed on mechanical ventilators. A total of 20 of these 60 patients (33%) had IFIs. Multivariate analysis indicated that independent risk factors for IFI were admission to an ICU more than 40 days after HSCT, graft versus host disease (GVHD), and high dose corticosteroid (<it>p </it>< 0.01 for all). The overall ICU mortality rate was 88% (53 of 60 patients), and was not significantly different for patients with IFIs (85%) and those without IFIs (90%, <it>p </it>= 0.676).</p> <p>Conclusion</p> <p>There was a high incidence of IFIs in HSCT patients requiring MV in the ICU in our study cohort. The independent risk factors for IFI are ICU admission more than 40 days after HSCT, GVHD, and use of high-dose corticosteroid.</p

    Induction of Bcl-2 Expression by Hepatitis B Virus Pre-S2 Mutant Large Surface Protein Resistance to 5-Fluorouracil Treatment in Huh-7 Cells

    Get PDF
    BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide with poor prognosis due to resistance to conventional chemotherapy and limited efficacy of radiotherapy. Our previous studies have indicated that expression of Hepatitis B virus pre-S2 large mutant surface antigen (HBV pre-S2Δ) is associated with a significant risk of developing HCC. However, the relationship between HBV pre-S2Δ protein and the resistance of chemotherapeutic drug treatment is still unclear. METHODOLOGY/PRINCIPAL FINDINGS: Here, we show that the expression of HBV pre-S2Δ mutant surface protein in Huh-7 cell significantly promoted cell growth and colony formation. Furthermore, HBV pre-S2Δ protein increased both mRNA (2.7±0.5-fold vs. vehicle, p=0.05) and protein (3.2±0.3-fold vs. vehicle, p=0.01) levels of Bcl-2 in Huh-7 cells. HBV pre-S2Δ protein also enhances Bcl-2 family, Bcl-xL and Mcl-1, expression in Huh-7 cells. Meanwhile, induction of NF-κB p65, ERK, and Akt phosphorylation, and GRP78 expression, an unfolded protein response chaperone, were observed in HBV pre-S2Δ and HBV pre-S-expressing cells. Induction of Bcl-2 expression by HBV pre-S2Δ protein resulted in resistance to 5-fluorouracil treatment in colony formation, caspase-3 assay, and cell apoptosis, and can enhance cell death by co-incubation with Bcl-2 inhibitor. Similarly, transgenic mice showed higher expression of Bcl-2 in liver tissue expressing HBV pre-S2Δ large surface protein in vivo. CONCLUSION/SIGNIFICANCE: Our result demonstrates that HBV pre-S2Δ increased Bcl-2 expression which plays an important role in resistance to 5-fluorouracil-caused cell death. Therefore, these data provide an important chemotherapeutic strategy in HBV pre-S2Δ-associated tumor

    The Critical Role of Early Dengue Surveillance and Limitations of Clinical Reporting - Implications for Non-Endemic Countries

    No full text
    The increasing dengue burden and epidemic severity worldwide have highlighted the need to improve surveillance. In non-endemic areas such as Taiwan, where outbreaks start mostly with imported cases from Southeast Asia, a closer examination of surveillance dynamics to detect cases early is necessary. To evaluate problems with dengue surveillance and investigate the involvement of different factors at various epidemic stages, we investigated 632 laboratory-confirmed indigenous dengue cases in Kaohsiung City, Taiwan during 2009-2010. The estimated sensitivity of clinical surveillance was 82.4% (521/632). Initially, the modified serological surveillance (targeting only the contacts of laboratory-confirmed dengue cases) identified clinically unrecognized afebrile cases in younger patients who visited private clinics and accounted for 30.4% (35/115) of the early-stage cases. Multivariate regression indicated that hospital/medical center visits [Adjusted Odds Ratio (aOR): 11.6, 95% confidence interval (CI): 6.3-21.4], middle epidemic stage [aOR: 2.4 (1.2-4.7)], fever [aOR: 2.3 (2.3-12.9)], and musculo-articular pain [aOR: 1.9 (1.05-3.3)] were significantly associated with clinical reporting. However, cases with pruritus/rash [aOR: 0.47 (0.26-0.83)] and diarrhea [aOR: 0.47 (0.26-0.85)] were underreported. In conclusion, multiple factors contributed to dengue surveillance problems. To prevent a large-scale epidemic and minimize severe dengue cases, there is a need for integrated surveillance incorporating entomological, clinical, serological, and virological surveillance systems to detect early cases, followed by immediate prevention and control measures and continuous evaluation to ensure effectiveness. This effort will be particularly important for an arbovirus, such as Zika virus, with a high asymptomatic infection ratio. For dengue-non-endemic countries, we recommend serological surveillance be implemented in areas with high Aedes mosquito indices or many breeding sites. Syndromic surveillance, spatial analysis and monitoring changes in epidemiological characteristics using a geographical information system, as well as epidemic prediction models involving epidemiological, meteorological and environmental variables will be helpful for early risk communication to increase awareness

    Hierarchical deployment of factors regulating temporal fate in a diverse neuronal lineage of the Drosophila central brain

    Get PDF
    The anterodorsal projection neuron lineage of Drosophila melanogaster produces 40 neuronal types in a stereotypic order. Here we take advantage of this complete lineage sequence to examine the role of known temporal fating factors, including Chinmo and the Hb/Kr/Pdm/Cas transcriptional cascade, within this diverse central brain lineage. Kr mutation affects the temporal fate of the neuroblast (NB) itself, causing a single fate to be skipped, whereas Chinmo null only elicits fate transformation of NB progeny without altering cell counts. Notably, Chinmo operates in two separate windows to prevent fate transformation (into the subsequent Chinmo-indenpendent fate) within each window. By contrast, Hb/Pdm/Cas play no detectable role, indicating that Kr either acts outside of the cascade identified in the ventral nerve cord or that redundancy exists at the level of fating factors. Therefore, hierarchical fating mechanisms operate within the lineage to generate neuronal diversity in an unprecedented fashion

    DICOM-Based Multi-Center Electronic Medical Records Management System to Support Clinical Diagnosis

    No full text
    [[abstract]]In the past, many of the medical information produced by hospitals (such as medical records or imagery) have had trouble being transferred from place to place; the main reason for this being the fference in the many formats that are used by each and every brand. With the development of the ages, the need for exchange of medical information has increased. Thus, imagery medical information uses the DICOM (Digital Image and Communication in Medicine) standard. The goal of this study is to establish a reformatting interface using the DICOM file management system to transfer paper-based records into DICOM format. Once in DICOM format, these records can then be sent to the DICOM server so that they may be accessed via the DICOM Viewer cross hospitals. This study also aims to transform text information into DICOM format so that files may be exchanged with other hospitals through DICOM’s secure system so that medical records can be incorporated into hospitals’ image systems to form a congregation of hospital resources

    Multiple eruptive myxoid dermatofibromas

    No full text
    Multiple eruptive dermatofibromas are a rare presentation of dermatofibroma and have been associated with altered immunity. A rare case of multiple eruptive myxoid dermatofibromas (MEMDFs), characterized by marked stromal mucin deposition, is reported herein; additionally, an in-depth discussion on the implication of altered immunity is presented. Because MEMDFs can be an initial manifestation of systemic lupus erythematosus, it is necessary for dermatologists to perform a skin biopsy for pathological diagnosis and a comprehensive survey for autoimmunity, infectious diseases, especially human immunodeficiency virus infection, hematologic diseases, and malignancies, or other immunodeficiency conditions when the patient is diagnosed with MEMDFs

    Lichen Simplex Chronicus Associated With Erectile Dysfunction: A Population-Based Retrospective Cohort Study.

    No full text
    An association between lichen simplex chronicus (LSC) and sexual dysfunction was explored. However, no data are available from investigations into the relationship between erectile dysfunction (ED) and LSC.This retrospective population-based cohort study aimed to clarify the risk of ED associated with LSC.By using the Taiwan National Health Insurance Research dataset, we identified 5611 male patients who had been newly diagnosed with LSC from 2000 to 2004. The date of diagnosis was identified as the index date. LSC patients with incomplete demographic information or with a history of ED before the index date were excluded. In total, 22444 age-matched patients without LSC were randomly selected as the non-LSC group based on a 1:4 ratio. Subsequence occurrence of ED was measured until 2011. The association between LSC and the risk of developing ED was estimated using Cox proportional hazard regression model.After adjusting for age and comorbidities, patients with LSC had a 1.74-fold greater risk of developing ED compared with those without LSC (95% confidence interval=1.44-2.10). LSC patients with comorbidities including diabetes, hyperlipidemia, hypertension, cardiovascular disease, peripheral arterial disease, chronic obstructive pulmonary disease, chronic kidney disease, depression, and anxiety were at a higher risk of ED compared with the non-LSC patients without comorbidities.LSC confers a greater risk in the development of ED. Physicians should be aware of the potential of ED occurrence in LSC patients
    corecore