599 research outputs found

    Label-free quantitative proteomics of CD133-positive liver cancer stem cells

    Full text link
    Abstract Background CD133-positive liver cancer stem cells, which are characterized by their resistance to conventional chemotherapy and their tumor initiation ability at limited dilutions, have been recognized as a critical target in liver cancer therapeutics. In the current work, we developed a label-free quantitative method to investigate the proteome of CD133-positive liver cancer stem cells for the purpose of identifying unique biomarkers that can be utilized for targeting liver cancer stem cells. Label-free quantitation was performed in combination with ID-based Elution time Alignment by Linear regression Quantitation (IDEAL-Q) and MaxQuant. Results Initially, IDEAL-Q analysis revealed that 151 proteins were differentially expressed in the CD133-positive hepatoma cells when compared with CD133-negative cells. We then analyzed these 151 differentially expressed proteins by MaxQuant software and identified 10 significantly up-regulated proteins. The results were further validated by RT-PCR, western blot, flow cytometry or immunofluorescent staining which revealed that prominin-1, annexin A1, annexin A3, transgelin, creatine kinase B, vimentin, and EpCAM were indeed highly expressed in the CD133-positive hepatoma cells. Conclusions These findings confirmed that mass spectrometry-based label-free quantitative proteomics can be used to gain insights into liver cancer stem cells.http://deepblue.lib.umich.edu/bitstream/2027.42/113089/1/12953_2012_Article_407.pd

    Comparative genome analysis of Spiroplasma melliferum IPMB4A, a honeybee-associated bacterium

    Get PDF
    Background: The genus Spiroplasma contains a group of helical, motile, and wall-less bacteria in the class Mollicutes. Similar to other members of this class, such as the animal-pathogenic Mycoplasma and the plant-pathogenic ‘Candidatus Phytoplasma’, all characterized Spiroplasma species were found to be associated with eukaryotic hosts. While most of the Spiroplasma species appeared to be harmless commensals of insects, a small number of species have evolved pathogenicity toward various arthropods and plants. In this study, we isolated a novel strain of honeybee-associated S. melliferum and investigated its genetic composition and evolutionary history by whole-genome shotgun sequencing and comparative analysis with other Mollicutes genomes. Results: The whole-genome shotgun sequencing of S. melliferum IPMB4A produced a draft assembly that was ~1.1 Mb in size and covered ~80% of the chromosome. Similar to other Spiroplasma genomes that have been studied to date, we found that this genome contains abundant repetitive sequences that originated from plectrovirus insertions. These phage fragments represented a major obstacle in obtaining a complete genome sequence of Spiroplasma with the current sequencing technology. Comparative analysis of S. melliferum IPMB4A with other Spiroplasma genomes revealed that these phages may have facilitated extensive genome rearrangements in these bacteria and contributed to horizontal gene transfers that led to species-specific adaptation to different eukaryotic hosts. In addition, comparison of gene content with other Mollicutes suggested that the common ancestor of the SEM (Spiroplasma, Entomoplasma, and Mycoplasma) clade may have had a relatively large genome and flexible metabolic capacity; the extremely reduced genomes of present day Mycoplasma and ‘Candidatus Phytoplasma’ species are likely to be the result of independent gene losses in these lineages. Conclusions: The findings in this study highlighted the significance of phage insertions and horizontal gene transfer in the evolution of bacterial genomes and acquisition of pathogenicity. Furthermore, the inclusion of Spiroplasma in comparative analysis has improved our understanding of genome evolution in Mollicutes. Future improvements in the taxon sampling of available genome sequences in this group are required to provide further insights into the evolution of these important pathogens of humans, animals, and plants

    Performance of Six Clinical Physiological Scoring Systems in Predicting In-Hospital Mortality in Elderly and Very Elderly Patients with Acute Upper Gastrointestinal Bleeding in Emergency Department

    Get PDF
    Background and Objectives: The aim of this study is to compare the performance of six clinical physiological-based scores, including the pre-endoscopy Rockall score, shock index (SI), age shock index (age SI), Rapid Acute Physiology Score (RAPS), Rapid Emergency Medicine Score (REMS), and Modified Early Warning Score (MEWS), in predicting in-hospital mortality in elderly and very elderly patients in the emergency department (ED) with acute upper gastrointestinal bleeding (AUGIB). Materials and Methods: Patients older than 65 years who visited the ED with a clinical diagnosis of AUGIB were enrolled prospectively from July 2016 to July 2021. The six scores were calculated and compared with in-hospital mortality. Results: A total of 336 patients were recruited, of whom 40 died. There is a significant difference between the patients in the mortality group and survival group in terms of the six scoring systems. MEWS had the highest area under the curve (AUC) value (0.82). A subgroup analysis was performed for a total of 180 very elderly patients (i.e., older than 75 years), of whom 27 died. MEWS also had the best predictive performance in this subgroup (AUC, 0.82). Conclusions: This simple, rapid, and obtainable-by-the-bed parameter could assist emergency physicians in risk stratification and decision making for this vulnerable group

    Optimization of a PVC Membrane for Reference Field Effect Transistors

    Get PDF
    For the miniaturization of ISFET sensing systems, the concept of a REFET with low ion sensitivity is proposed to replace the conventional reference electrodes through the arrangement of a quasi reference electrode and a differential readout circuit. In this study, an ion-unblocking membrane was used as the top layer of a REFET. To optimize the REFET performance, the influences of the silylating process, different plasticizers, and the composition of the PVC cocktails were investigated. A low sensitivity (10.4 ± 2.2 mV/pH) and high linearity (99.7 ± 0.3 %) in the range from pH 2.2 to pH 11.6 was obtained for the REFET with a 60 wt.% DNP/(DNP + PVC) membrane. To evaluate the long term stability, the drift coefficient was estimated, and for the best REFET, it was −0.74 mV/h. Two criteria for assessing the lifetime of REFETs were used, namely the increase in pH sensitivity to a value higher than 15 mV/pH and the degradation of linearity below 99 %. For the best REFET, it was approximately 15 days

    Biodistribution and pharmacokinetics of 188Re-liposomes and their comparative therapeutic efficacy with 5-fluorouracil in C26 colonic peritoneal carcinomatosis mice

    Get PDF
    Chia-Che Tsai1, Chih-Hsien Chang1, Liang-Cheng Chen1, Ya-Jen Chang1, Keng-Li Lan2, Yu-Hsien Wu1, Chin-Wei Hsu1, I-Hsiang Liu1, Chung-Li Ho1, Wan-Chi Lee1, Hsiao-Chiang Ni1, Tsui-Jung Chang1, Gann Ting3, Te-Wei Lee11Institute of Nuclear Energy Research, Taoyuan, 2Cancer Center, Taipei Veterans General Hospital, Taipei, 3National Health Research Institutes, Taipei, Taiwan, ROCBackground: Nanoliposomes are designed as carriers capable of packaging drugs through passive targeting tumor sites by enhanced permeability and retention (EPR) effects. In the present study the biodistribution, pharmacokinetics, micro single-photon emission computed tomography (micro-SPECT/CT) image, dosimetry, and therapeutic efficacy of 188Re-labeled nanoliposomes (188Re-liposomes) in a C26 colonic peritoneal carcinomatosis mouse model were evaluated.Methods: Colon carcinoma peritoneal metastatic BALB/c mice were intravenously administered 188Re-liposomes. Biodistribution and micro-SPECT/CT imaging were performed to determine the drug profile and targeting efficiency of 188Re-liposomes. Pharmacokinetics study was described by a noncompartmental model. The OLINDA|EXM® computer program was used for the dosimetry evaluation. For therapeutic efficacy, the survival, tumor, and ascites inhibition of mice after treatment with 188Re-liposomes and 5-fluorouracil (5-FU), respectively, were evaluated and compared.Results: In biodistribution, the highest uptake of 188Re-liposomes in tumor tissues (7.91% ± 2.02% of the injected dose per gram of tissue [%ID/g]) and a high tumor to muscle ratio (25.8 ± 6.1) were observed at 24 hours after intravenous administration. The pharmacokinetics of 188Re-liposomes showed high circulation time and high bioavailability (mean residence time [MRT] = 19.2 hours, area under the curve [AUC] = 820.4%ID/g*h). Micro-SPECT/CT imaging of 188Re-liposomes showed a high uptake and targeting in ascites, liver, spleen, and tumor. The results were correlated with images from autoradiography and biodistribution data. Dosimetry study revealed that the 188Re-liposomes did not cause high absorbed doses in normal tissue but did in small tumors. Radiotherapeutics with 188Re-liposomes provided better survival time (increased by 34.6% of life span; P < 0.05), tumor and ascites inhibition (decreased by 63.4% and 83.3% at 7 days after treatment; P < 0.05) in mice compared with chemotherapeutics of 5-fluorouracil (5-FU).Conclusion: The use of 188Re-liposomes for passively targeted tumor therapy had greater therapeutic effect than the currently clinically applied chemotherapeutics drug 5-FU in a colonic peritoneal carcinomatosis mouse model. This result suggests that 188Re-liposomes have potential benefit and are safe in treating peritoneal carcinomatasis of colon cancer.Keywords: biodistribution, dosimetry, 5-fluorouracil, micro-SPECT/CT, 188Re-liposome
    corecore