89 research outputs found

    Increased CDC20 expression is associated with pancreatic ductal adenocarcinoma differentiation and progression

    Get PDF
    <p>Abstract</p> <p>Purpose</p> <p>Cell division cycle 20 (CDC20) homolog is an anaphase-promoting complex activator that is essential for cell division, but whether its expression in pancreatic ductal adenocarcinoma (PDAC) is significant is unknown. In this retrospective study, we determined whether aberrant CDC20 expression can be used as a biomarker in pancreatic ductal adenocarcinoma (PDAC) tumorigenesis and whether its expression reflects clinical progression.</p> <p>Experimental design</p> <p>We compared CDC20 expression levels in normal, cancerous, and inflamed pancreatic tissues from stage II PDAC patients with clinical outcomes and determined CDC20 levels in seven PDAC cell lines. CDC20 was identified using a cDNA microarray database containing gene expression profiles for PDAC tissues and cell lines and chronic pancreatitis and normal pancreas tissues. Its expression was confirmed by real-time quantitative reverse-transcriptase-polymerase chain reaction (qRT-PCR). An immunohistochemical analysis of tissue microarrays from resected PDAC tumors and paired benign pancreatic tissues was done and CDC20 levels were correlated with clinical outcome.</p> <p>Results</p> <p>Fifty-six patients were included in this study. A microarray analysis revealed 5-fold higher CDC20 expression in PDAC tissue than in chronic pancreatitis tissue. A qRT-PCR analysis confirmed a mean 20-fold higher CDC20 level in PDAC tissue than in normal pancreas and pancreatitis tissue. RNA and protein CDC20 expression was detected in several PDAC cell lines. An immunohistochemical analysis revealed higher CDC20 protein expression levels in PDAC tissue than in normal pancreas tissue, and high CDC20 expression was associated with poor differentiation (<it>P </it>= 0.020) and a significantly lower 5-year recurrence-free survival rate (<it>P </it>= 0.039); we also found a trend toward a shorter overall survival duration.</p> <p>Conclusions</p> <p>Aberrant CDC20 expression may play an important role in PDAC tumorigenesis and progression and may thus be useful as a marker of disease progression and prognosis and as a therapeutic target.</p

    Resectable adenocarcinomas in the pancreatic head: the retroperitoneal resection margin is an independent prognostic factor

    Get PDF
    Pancreatic cancer is a lethal disease, and even after assumed margin-free pancreatoduodenectomy, most patients die within few years. The aims were to evaluate the importance of standardised histopathologic assessment for adequacy of reporting and survival estimates, and to report on prognostic factors in a setting of standardised histopathologic assessment. We performed immunohistochemical evaluation, slide review, and review of histopathologic reports from all pancreatoduodenectomies at Rikshospitalet University Hospital in 1980–2004. Reports from 1998-2004 at this institution were compared with reports from all other Norwegian institutions in the same period. Standardised histopathologic assessment and reporting was found necessary to avoid underestimation of poor prognostic factors, and to avoid misdiagnosis of tumours originating from non-pancreatic tissue (ampulla, distal bile duct, duodenum). Standardised histopathology was more important than surgical volume for completeness of reporting and for reliability of survival estimates, particularly with respect to lymph node evaluation. Immunostaining for MUC1 and MUC4 identified a subgroup of patients with particularly poor prognosis. Standardised histopathologic evaluation should be a first prerequisite to assure adequate histopathology after pancreatoduodenectomy. Immunostaining may identify tumour markers potentially targetable in future adjuvant treatments for pancreatic cancer

    'Mitochondrial energy imbalance and lipid peroxidation cause cell death in Friedreich's ataxia'

    Get PDF
    Friedreich's ataxia (FRDA) is an inherited neurodegenerative disease. The mutation consists of a GAA repeat expansion within the FXN gene, which downregulates frataxin, leading to abnormal mitochondrial iron accumulation, which may in turn cause changes in mitochondrial function. Although, many studies of FRDA patients and mouse models have been conducted in the past two decades, the role of frataxin in mitochondrial pathophysiology remains elusive. Are the mitochondrial abnormalities only a side effect of the increased accumulation of reactive iron, generating oxidative stress? Or does the progressive lack of iron-sulphur clusters (ISCs), induced by reduced frataxin, cause an inhibition of the electron transport chain complexes (CI, II and III) leading to reactive oxygen species escaping from oxidative phosphorylation reactions? To answer these crucial questions, we have characterised the mitochondrial pathophysiology of a group of disease-relevant and readily accessible neurons, cerebellar granule cells, from a validated FRDA mouse model. By using live cell imaging and biochemical techniques we were able to demonstrate that mitochondria are deregulated in neurons from the YG8R FRDA mouse model, causing a decrease in mitochondrial membrane potential (▔Κm) due to an inhibition of Complex I, which is partially compensated by an overactivation of Complex II. This complex activity imbalance leads to ROS generation in both mitochondrial matrix and cytosol, which results in glutathione depletion and increased lipid peroxidation. Preventing this increase in lipid peroxidation, in neurons, protects against in cell death. This work describes the pathophysiological properties of the mitochondria in neurons from a FRDA mouse model and shows that lipid peroxidation could be an important target for novel therapeutic strategies in FRDA, which still lacks a cure

    Pathogenic p62/SQSTM1 mutations impair energy metabolism through limitation of mitochondrial substrates

    Get PDF
    Abnormal mitochondrial function has been found in patients with frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). Mutations in the p62 gene (also known as SQSTM1) which encodes the p62 protein have been reported in both disorders supporting the idea of an ALS/FTD continuum. In this work the role of p62 in energy metabolism was studied in fibroblasts from FTD patients carrying two independent pathogenic mutations in the p62 gene, and in a p62-knock-down (p62 KD) human dopaminergic neuroblastoma cell line (SH-SY5Y). We found that p62 deficiency is associated with inhibited complex I mitochondrial respiration due to lack of NADH for the electron transport chain. This deficiency was also associated with increased levels of NADPH reflecting a higher activation of pentose phosphate pathway as this is accompanied with higher cytosolic reduced glutathione (GSH) levels. Complex I inhibition resulted in lower mitochondrial membrane potential and higher cytosolic ROS production. Pharmacological activation of transcription factor Nrf2 increased mitochondrial NADH levels and restored mitochondrial membrane potential in p62-deficient cells. Our results suggest that the phenotype is caused by a loss-of-function effect, because similar alterations were found both in the mutant fibroblasts and the p62 KD model. These findings highlight the implication of energy metabolism in pathophysiological events associated with p62 deficiency

    How to prevent ROP in preterm infants in Indonesia?

    Get PDF
    Background and Aims: Retinopathy of prematurity (ROP) is a severe disease in preterm infants. It is seen more frequently in Low-Middle Income Countries (LMIC) like Indonesia compared to High-Income Countries (HIC). Risk factors for ROP development are -extreme- preterm birth, use of oxygen, neonatal infections, respiratory problems, inadequate nutrition, and blood and exchange transfusions. In this paper, we give an overview of steps that can be taken in LMIC to prevent ROP and provide guidelines for screening and treating ROP. Methods: Based on the literature search and data obtained by us in Indonesia's studies, we propose guidelines for the prevention, screening, and treatment of ROP in preterm infants in LMIC. Results: Prevention of ROP starts before birth with preventing preterm labor, transferring a mother who might deliver <32 weeks to a perinatal center and giving corticosteroids to mothers that might deliver <34 weeks. Newborn resuscitation must be done using room air or, in the case of very preterm infants (<29-32 weeks) by using 30% oxygen. Respiratory problems must be prevented by starting continuous positive airway pressure (CPAP) in all preterm infants <32 weeks and in case of respiratory problems in more mature infants. If needed, the surfactant should be given in a minimally invasive manner, as ROP's lower incidence was found using this technique. The use of oxygen must be strictly regulated with a saturation monitor of 91-95%. Infections must be prevented as much as possible. Both oral and parenteral nutrition should be started in all preterm infants on day one of life with preferably mothers' milk. Blood transfusions can be prevented by reducing the amount of blood needed for laboratory analysis. Discussion: Preterm babies should be born in facilities able to care for them optimally. The use of oxygen must be strictly regulated. ROP screening is mandatory in infants born <34 weeks, and infants who received supplemental oxygen for a prolonged period. In case of progression of ROP, immediate mandatory treatment is required. Conclusion: Concerted action is needed to reduce the incidence of ROP in LMIC. "STOP - R1O2P3" is an acronym that can help implement standard practices in all neonatal intensive care units in LMIC to prevent development and progression

    Beam-Target Double Spin Asymmetry A_LT in Charged Pion Production from Deep Inelastic Scattering on a Transversely Polarized He-3 Target at 1.4<Q^2<2.7 GeV^2

    Full text link
    We report the first measurement of the double-spin asymmetry ALTA_{LT} for charged pion electroproduction in semi\nobreakdash-inclusive deep\nobreakdash-inelastic electron scattering on a transversely polarized 3^{3}He target. The kinematics focused on the valence quark region, 0.16<x<0.350.16<x<0.35 with 1.4<Q2<2.7 GeV21.4<Q^{2}<2.7\,\textrm{GeV}^{2}. The corresponding neutron ALTA_{LT} asymmetries were extracted from the measured 3^{3}He asymmetries and proton over 3^{3}He cross section ratios using the effective polarization approximation. These new data probe the transverse momentum dependent parton distribution function g1Tqg_{1T}^{q} and therefore provide access to quark spin-orbit correlations. Our results indicate a positive azimuthal asymmetry for π−\pi^{-} production on 3^{3}He and the neutron, while our π+\pi^{+} asymmetries are consistent with zero.Comment: 6 pages, 2 figures, 1 tables, published in PR

    Single Spin Asymmetries in Charged Pion Production from Semi-Inclusive Deep Inelastic Scattering on a Transversely Polarized 3^3He Target

    Full text link
    We report the first measurement of target single spin asymmetries in the semi-inclusive 3He(e,eâ€Čπ±)X^3{He}(e,e'\pi^\pm)X reaction on a transversely polarized target. The experiment, conducted at Jefferson Lab using a 5.9 GeV electron beam, covers a range of 0.14 <x<< x < 0.34 with 1.3 <Q2<<Q^2< 2.7 GeV2^2. The Collins and Sivers moments were extracted from the azimuthal angular dependence of the measured asymmetries. The extracted π±\pi^\pm Collins moments for 3^3He are consistent with zero, except for the π+\pi^+ moment at x=0.34x=0.34, which deviates from zero by 2.3σ\sigma. While the π−\pi^- Sivers moments are consistent with zero, the π+\pi^+ Sivers moments favor negative values. The neutron results were extracted using the nucleon effective polarization and the measured cross section ratio of proton to 3^3He, and are largely consistent with the predictions of phenomenological fits and quark model calculations.Comment: 6 pages, 2 figures, 2 tables, published in PR

    Identifying an indoor air exposure limit for formaldehyde considering both irritation and cancer hazards

    Get PDF
    Formaldehyde is a well-studied chemical and effects from inhalation exposures have been extensively characterized in numerous controlled studies with human volunteers, including asthmatics and other sensitive individuals, which provide a rich database on exposure concentrations that can reliably produce the symptoms of sensory irritation. Although individuals can differ in their sensitivity to odor and eye irritation, the majority of authoritative reviews of the formaldehyde literature have concluded that an air concentration of 0.3 ppm will provide protection from eye irritation for virtually everyone. A weight of evidence-based formaldehyde exposure limit of 0.1 ppm (100 ppb) is recommended as an indoor air level for all individuals for odor detection and sensory irritation. It has recently been suggested by the International Agency for Research on Cancer (IARC), the National Toxicology Program (NTP), and the US Environmental Protection Agency (US EPA) that formaldehyde is causally associated with nasopharyngeal cancer (NPC) and leukemia. This has led US EPA to conclude that irritation is not the most sensitive toxic endpoint and that carcinogenicity should dictate how to establish exposure limits for formaldehyde. In this review, a number of lines of reasoning and substantial scientific evidence are described and discussed, which leads to a conclusion that neither point of contact nor systemic effects of any type, including NPC or leukemia, are causally associated with exposure to formaldehyde. This conclusion supports the view that the equivocal epidemiology studies that suggest otherwise are almost certainly flawed by identified or yet to be unidentified confounding variables. Thus, this assessment concludes that a formaldehyde indoor air limit of 0.1 ppm should protect even particularly susceptible individuals from both irritation effects and any potential cancer hazard

    International Consensus Statement on Rhinology and Allergy: Rhinosinusitis

    Get PDF
    Background: The 5 years since the publication of the first International Consensus Statement on Allergy and Rhinology: Rhinosinusitis (ICAR‐RS) has witnessed foundational progress in our understanding and treatment of rhinologic disease. These advances are reflected within the more than 40 new topics covered within the ICAR‐RS‐2021 as well as updates to the original 140 topics. This executive summary consolidates the evidence‐based findings of the document. Methods: ICAR‐RS presents over 180 topics in the forms of evidence‐based reviews with recommendations (EBRRs), evidence‐based reviews, and literature reviews. The highest grade structured recommendations of the EBRR sections are summarized in this executive summary. Results: ICAR‐RS‐2021 covers 22 topics regarding the medical management of RS, which are grade A/B and are presented in the executive summary. Additionally, 4 topics regarding the surgical management of RS are grade A/B and are presented in the executive summary. Finally, a comprehensive evidence‐based management algorithm is provided. Conclusion: This ICAR‐RS‐2021 executive summary provides a compilation of the evidence‐based recommendations for medical and surgical treatment of the most common forms of RS

    pbp2229-mediated nisin resistance mechanism in <I>Listeria monocytogenes </I>confers cross-protection to class IIa bacteriocins and affects virulence gene expression

    No full text
    NatuurwetenskappeBiochemiePlease help us populate SUNScholar with the post print version of this article. It can be e-mailed to: [email protected]
    • 

    corecore