3,775 research outputs found

    In vivo 4-dimensional tracking of hematopoietic stem and progenitor cells in adult mouse calvarial bone marrow

    No full text
    Through a delicate balance between quiescence and proliferation, self renewal and production of differentiated progeny, hematopoietic stem cells (HSCs) maintain the turnover of all mature blood cell lineages. The coordination of the complex signals leading to specific HSC fates relies upon the interaction between HSCs and the intricate bone marrow microenvironment, which is still poorly understood[1-2]. We describe how by combining a newly developed specimen holder for stable animal positioning with multi-step confocal and two-photon in vivo imaging techniques, it is possible to obtain high-resolution 3D stacks containing HSPCs and their surrounding niches and to monitor them over time through multi-point time-lapse imaging. High definition imaging allows detecting ex vivo labeled hematopoietic stem and progenitor cells (HSPCs) residing within the bone marrow. Moreover, multi-point time-lapse 3D imaging, obtained with faster acquisition settings, provides accurate information about HSPC movement and the reciprocal interactions between HSPCs and stroma cells. Tracking of HSPCs in relation to GFP positive osteoblastic cells is shown as an exemplary application of this method. This technique can be utilized to track any appropriately labeled hematopoietic or stromal cell of interest within the mouse calvarium bone marrow space

    Erlotinib as salvage treatment after failure to first-line Gefitinib in non-small cell lung cancer

    Get PDF
    Purpose Chemotherapy is the mainstay treatment for advanced non-small cell lung cancer (NSCLC). Gefitinib, an epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI), has been recently shown to be effective as a first-line treatment in Asian patients with advanced NSCLC, especially for those with favourable clinical features such as female, non-smoker and adenocarcinoma. However, resistance to gefitinib ensues invariably and there is little evidence as for the effectiveness of subsequent salvage treatment. The purpose of this study is to evaluate the efficacy of erlotinib, another EGFR-TKI, after failed first-line use of gefitinib. Method Retrospective review of NSCLC patients with favourable clinical features who received gefitinib as firstline treatment and subsequent salvage treatment with erlotinib. Results A total of 21 patients with NSCLC were included in the study. Among them, 18 (85.7%) patients had disease control with gefitinib and 12 (57.1%) patients with salvage erlotinib. There was an association between the disease control with gefitinib and erlotinib (p = 0.031). The disease control rate of erlotinib was independent of the chemotherapy use between the two EGFR-TKIs. Conclusion For NSCLC patients with favourable clinical features, erlotinib was effective in those who had prior disease control with first-line gefitinib. © Springer-Verlag 2009.published_or_final_versionSpringer Open Choice, 01 Dec 201

    Predominance of pHK01-like incompatibility group FII plasmids encoding CTX-M-14 among extended-spectrum beta-lactamase-producing Escherichia coli in Hong Kong, 1996-2008

    Get PDF
    This study assessed the temporal changes in the molecular epidemiology of bacteremic Escherichia coli isolates producing CTX-M-14 in Hong Kong. Blood isolates from 1996 to 1998 (period 1, n = 50) and 2007 to 2008 (period 2, n = 117) were investigated by molecular methods. CTX-M-type ESBL was carried by 98.2% (164/167) of the isolates. In both periods, the CTX-M-9 group and CTX-M-14 allele were the predominant ESBL type. The major clones were found to change from ST68 and ST405 in period 1 to ST131, ST69, and ST12 in period 2. Among 65 CTX-M-14-producing plasmids investigated further, 54 had the FII replicon. Replicon sequence typing and plasmid polymerase chain reaction-restriction fragment length polymorphism showed that 79.6% (43/54) of the FII plasmid subset was similar to the completely sequenced plasmid, pHK01 (human urine, Hong Kong, 2004). These pHK01-like plasmids were found to have spread to the major clones (ST68, ST405, and ST131) and multiple singleton isolates of all 4 phylogenetic groups. © 2012 Elsevier Inc.postprin

    Copy number gain of granulin-epithelin precursor (GEP) at chromosome 17q21 associates with overexpression in human liver cancer

    Get PDF
    Background: Granulin-epithelin precursor (GEP), a secretory growth factor, demonstrated overexpression in various human cancers, however, mechanism remain elusive. Primary liver cancer, hepatocellular carcinoma (HCC), ranks the second in cancer-related death globally. GEP controlled growth, invasion, metastasis and chemo-resistance in liver cancer. Noted that GEP gene locates at 17q21 and the region has been frequently reported to be amplified in subset of HCC. The study aims to investigate if copy number gain would associate with GEP overexpression. Methods: Quantitative Microsatellite Analysis (QuMA) was used to quantify the GEP DNA copy number, and fluorescent in situ hybridization (FISH) was performed to consolidate the amplification status. GEP gene copy number, mRNA expression level and clinico-pathological features were analyzed. Results: GEP DNA copy number determined by QuMA corroborated well with the FISH data, and the gene copy number correlated with the expression levels (n = 60, r = 0.331, P = 0.010). Gain of GEP copy number was observed in 20% (12/60) HCC and associated with hepatitis B virus infection status (P = 0.015). In HCC with increased GEP copy number, tight association between GEP DNA and mRNA levels were observed (n = 12, r = 0.664, P = 0.019). Conclusions: Gain of the GEP gene copy number was observed in 20% HCC and the frequency comparable to literatures reported on the chromosome region 17q. Increased gene copy number contributed to GEP overexpression in subset of HCC. © Yung et al; licensee BioMed Central.published_or_final_versio

    Dissemination of pHK01-like incompatibility group IncFII plasmids encoding CTX-M-14 in Escherichia coli from human and animal sources

    Get PDF
    Few studies have compared CTX-M encoding plasmids identified in different ecological sources. This study aimed to analyze and compare the molecular epidemiology of plasmids encoding CTX-M-14 among strains from humans and animals. The CTX-M-14 encoding plasmids in 160 Escherichia coli isolates from animal faecal (14 pigs, 16 chickens, 12 cats, 8 cattle, 5 dogs and 3 rodents), human faecal (45 adults and 20 children) and human urine (37 adults) sources in 2002-2010 were characterized by molecular methods. The replicon types of the CTX-M-14 encoding plasmids were IncFII (n=61), I1-Iγ (n=24), other F types (n=23), B/O (n=10), K (n=6), N (n=3), A/C (n=1), HI1 (n=1), HI2 (n=1) and nontypeable (n=30). The genetic environment, ISEcp1 - bla CTX-M-14 - IS903 was found in 89.7% (52/58), 87.7% (57/65) and 86.5% (32/37) of the animal faecal, human faecal and human urine isolates, respectively. Subtyping of the 61 IncFII incompatibility group plasmids by replicon sequence typing, plasmid PCR-restriction fragment length polymorphism and marker genes (yac, malB, eitA/eitC and parB/A) profiles showed that 31% (18/58), 30.6% (20/65) and 37.8% (14/37) of the plasmids originating from animal faecal, human faecal and human urine isolates, respectively, were pHK01-like. These 52 pHK01-like plasmids originated from diverse human (20 faecal isolates from 2002, 2007 to 2008, 14 urinary isolates from 2004) and animal (all faecal, 1 cattle, 1 chicken, 5 pigs, 9 cats, 1 dog, 1 rodent from 2008 to 2010) sources. In conclusion, this study highlights the importance of the IncFII group, pHK01-like plasmids in the dissemination of CTX-M-14 among isolates from diverse sources. © 2012 Elsevier B.V.postprin

    Novel use of Tachosil® in Bilateral Nerve-sparing Robot-assisted Laparoscopic Radical Prostatectomy (biNS-RaLRP)

    Get PDF
    Oral (Free Paper) Session 2I - Uro-Oncology: Prostate & Kidney: no. OP.2-4OBJECTIVE: To investigate the novel use of Tachosil® (an absorbable fibrin sealant patch) in biNS-RaLRP with conventional athermal dissection technique …postprin

    Effect of Intensive Patient Education vs Placebo Patient Education on Outcomes in Patients with Acute Low Back Pain: A Randomized Clinical Trial

    Get PDF
    © 2018 2018 American Medical Association. All rights reserved. Importance: Many patients with acute low back pain do not recover with basic first-line care (advice, reassurance, and simple analgesia, if necessary). It is unclear whether intensive patient education improves clinical outcomes for those patients already receiving first-line care. Objective: To determine the effectiveness of intensive patient education for patients with acute low back pain. Design, Setting, and Participants: This randomized, placebo-controlled clinical trial recruited patients from general practices, physiotherapy clinics, and a research center in Sydney, Australia, between September 10, 2013, and December 2, 2015. Trial follow-up was completed in December 17, 2016. Primary care practitioners invited 618 patients presenting with acute low back pain to participate. Researchers excluded 416 potential participants. All of the 202 eligible participants had low back pain of fewer than 6 weeks' duration and a high risk of developing chronic low back pain according to Predicting the Inception of Chronic Pain (PICKUP) Tool, a validated prognostic model. Participants were randomized in a 1:1 ratio to either patient education or placebo patient education. Interventions: All participants received recommended first-line care for acute low back pain from their usual practitioner. Participants received additional 2 × 1-hour sessions of patient education (information on pain and biopsychosocial contributors plus self-management techniques, such as remaining active and pacing) or placebo patient education (active listening, without information or advice). Main Outcomes and Measures: The primary outcome was pain intensity (11-point numeric rating scale) at 3 months. Secondary outcomes included disability (24-point Roland Morris Disability Questionnaire) at 1 week, and at 3, 6, and 12 months. Results: Of 202 participants randomized for the trial, the mean (SD) age of participants was 45 (14.5) years and 103 (51.0%) were female. Retention rates were greater than 90% at all time points. Intensive patient education was not more effective than placebo patient education at reducing pain intensity (3-month mean [SD] pain intensity: 2.1 [2.4] vs 2.4 [2.2]; mean difference at 3 months, -0.3 [95% CI, -1.0 to 0.3]). There was a small effect of intensive patient education on the secondary outcome of disability at 1 week (mean difference, -1.6 points on a 24-point scale [95% CI, -3.1 to -0.1]) and 3 months (mean difference, -1.7 points, [95% CI, -3.2 to -0.2]) but not at 6 or 12 months. Conclusions and Relevance: Adding 2 hours of patient education to recommended first-line care for patients with acute low back pain did not improve pain outcomes. Clinical guideline recommendations to provide complex and intensive support to high-risk patients with acute low back pain may have been premature. Trial Registration: Australian Clinical Trial Registration Number: 12612001180808

    CXCR2 deficient mice display macrophage-dependent exaggerated acute inflammatory responses

    Get PDF
    CXCR2 is an essential regulator of neutrophil recruitment to inflamed and damaged sites and plays prominent roles in inflammatory pathologies and cancer. It has therefore been highlighted as an important therapeutic target. However the success of the therapeutic targeting of CXCR2 is threatened by our relative lack of knowledge of its precise in vivo mode of action. Here we demonstrate that CXCR2-deficient mice display a counterintuitive transient exaggerated inflammatory response to cutaneous and peritoneal inflammatory stimuli. In both situations, this is associated with reduced expression of cytokines associated with the resolution of the inflammatory response and an increase in macrophage accumulation at inflamed sites. Analysis using neutrophil depletion strategies indicates that this is a consequence of impaired recruitment of a non-neutrophilic CXCR2 positive leukocyte population. We suggest that these cells may be myeloid derived suppressor cells. Our data therefore reveal novel and previously unanticipated roles for CXCR2 in the orchestration of the inflammatory response

    Hepatitis B virus infected physicians and disclosure of transmission risks to patients: A critical analysis

    Get PDF
    BACKGROUND: The potential for transmission of blood-borne pathogens such as hepatitis B virus from infected healthcare workers to patients is an important and difficult issue facing healthcare policymakers internationally. Law and policy on the subject is still in its infancy, and subject to a great degree of uncertainty and controversy. Policymakers have made few recommendations regarding the specifics of practice restriction for health care workers who are hepatitis B seropositive. Generally, they have deferred this work to vaguely defined "expert panels" which will have the power to dictate the conditions under which infected health care workers may continue to practice. DISCUSSION: In this paper we use recent Canadian policy statements as a critical departure point to propose more specific recommendations regarding disclosure of transmission risks in a way that minimizes practice restriction of hepatitis B seropositive health care workers without compromising patient safety. The range of arguments proposed in the literature are critically examined from the perspective of ethical analysis. SUMMARY: A process for considering the ethical implications of the disclosure of the sero-status of health care workers is advanced that considers the varied perspectives of different stakeholders
    corecore