13 research outputs found
Prevalence of genetic variants of keratins 8 and 18 in patients with drug-induced liver injury
Abstract Background Keratin 8 and 18 (K8/K18) cytoskeletal proteins protect hepatocytes from undergoing apoptosis and their mutations predispose to adverse outcomes in acute liver failure (ALF). All known K8/K18 variants occur at relatively non-conserved residues and do not cause keratin cytoskeleton reorganization, whereas epidermal keratin-conserved residue mutations disrupt the keratin cytoskeleton and cause severe skin disease. The aim of our study was to identify keratin variants in idiosyncratic drug-induced liver injury (DILI). Methods Genomic DNA was isolated from 800 patients enrolled in an ongoing US multicenter study, with DILI attributed to a wide range of drugs. Specific K8/K18 exonic regions were PCR-amplified and screened by denaturing HPLC followed by DNA sequencing. The functional impact of keratin variants was assessed using cell transfection and immune staining. Results Heterozygous and compound amino acid-altering K8/K18 variants were identified in 86 DILI patients and non-coding variants in 15 subjects. Five novel amino acid-altering (K8 Lys393Arg, K8 Ala351Val, K8 Ala358Val, K8 Ile346Val, K18 Asp89His) and two non-coding variants were observed. Several variants segregated with specific ethnic backgrounds but were found at similar frequencies in DILI subjects and ethnically matched population controls. Notably, variants in highly conserved residues of K8 Lys393Arg (ezetimibe/simvastatin-related) and K18 Asp89His (isoniazid-related) were found in patients with fatal DILI. These novel variants also led to keratin network disruption in transfected cells. Conclusions Novel K8/K18 cytoskeleton-disrupting variants were identified in two patients and segregated with fatal DILI. Other non-cytoskeleton-disrupting keratin variants did not preferentially associate with DILI
Telomerase and pluripotency factors jointly regulate stemness in pancreatic cancer stem cells
© 2021 by the authors.To assess the role of telomerase activity and telomere length in pancreatic CSCs we used different CSC enrichment methods (CD133, ALDH, sphere formation) in primary patient-derived pancreatic cancer cells. We show that CSCs have higher telomerase activity and longer telomeres than bulk tumor cells. Inhibition of telomerase activity, using genetic knockdown or pharmacological inhibitor (BIBR1532), resulted in CSC marker depletion, abrogation of sphere formation in vitro and reduced tumorigenicity in vivo. Furthermore, we identify a positive feedback loop between stemness factors (NANOG, OCT3/4, SOX2, KLF4) and telomerase, which is essential for the self-renewal of CSCs. Disruption of the balance between telomerase activity and stemness factors eliminates CSCs via induction of DNA damage and apoptosis in primary patient-derived pancreatic cancer samples, opening future perspectives to avoid CSC-driven tumor relapse. In the present study, we demonstrate that telomerase regulation is critical for the “stemness” maintenance in pancreatic CSCs and examine the effects of telomerase inhibition as a potential treatment option of pancreatic cancer. This may significantly promote our understanding of PDAC tumor biology and may result in improved treatment for pancreatic cancer patients.This research was funded by a Max Eder Fellowship of the German Cancer Aid (111746), a German Cancer Aid Priority Program ‘Translational Oncology’ 70112505, by a Collaborative Research Centre grant (316249678—SFB 1279) of the German Research Foundation, and by a Hector Foundation Cancer Research grant (M65.1) to P.C.H., B.S.J. is supported by a Rámon y Cajal Merit Award (RYC2012-12104) from the Ministerio de Economía y Competitividad, Spain and a Coordinated grant (GC16173694BARB) from the Fundación Asociación Española Contra el Cáncer (AECC). K.W. is supported by a Baustein 3.2 by Ulm University
Telomerase and pluripotency factors jointly regulate stemness in pancreatic cancer stem cells
To assess the role of telomerase activity and telomere length in pancreatic CSCs we used different CSC enrichment methods (CD133, ALDH, sphere formation) in primary patient-derived pancreatic cancer cells. We show that CSCs have higher telomerase activity and longer telomeres than bulk tumor cells. Inhibition of telomerase activity, using genetic knockdown or pharmacological inhibitor (BIBR1532), resulted in CSC marker depletion, abrogation of sphere formation in vitro and reduced tumorigenicity in vivo. Furthermore, we identify a positive feedback loop between stemness factors (NANOG, OCT3/4, SOX2, KLF4) and telomerase, which is essential for the self-renewal of CSCs. Disruption of the balance between telomerase activity and stemness factors eliminates CSCs via induction of DNA damage and apoptosis in primary patient-derived pancreatic cancer samples, opening future perspectives to avoid CSC-driven tumor relapse. In the present study, we demonstrate that telomerase regulation is critical for the “stemness” maintenance in pancreatic CSCs and examine the effects of telomerase inhibition as a potential treatment option of pancreatic cancer. This may significantly promote our understanding of PDAC tumor biology and may result in improved treatment for pancreatic cancer patientsThis research was funded by a Max Eder Fellowship of the German Cancer Aid (111746), a
German Cancer Aid Priority Program ‘Translational Oncology’ 70112505, by a Collaborative Research
Centre grant (316249678—SFB 1279) of the German Research Foundation, and by a Hector Foundation
Cancer Research grant (M65.1) to P.C.H., B.S.J. is supported by a Rámon y Cajal Merit Award (RYC-
2012-12104) from the Ministerio de Economía y Competitividad, Spain and a Coordinated grant
(GC16173694BARB) from the Fundación Asociación Española Contra el Cáncer (AECC). K.W. is
supported by a Baustein 3.2 by Ulm University
Keratin 8 variants are infrequent in patients with alcohol-related liver cirrhosis and do not associate with development of hepatocellular carcinoma
Desertification indicators as diagnosis criteria for desertification risk assessment in Europe
8 páginas, 4 figuras.Despite the seriousness of the environmental and socio-economic impacts of desertification, few efforts have been made to devise diagnostic and monitoring techniques for appraising the status and trend of desertification. Indicators are integrated and synthetic information that can provide data on threshold levels, status and evolution of relevant physical, chemical, biological and anthropogenic processes. Existing studies have taken a global perspective, and most have dealt with rangeland conditions. Moreover, the zones usually studied have included countries whose socio-economic and cultural backgrounds differ from those prevailing in Europe. This paper presents a methodology and discussion of indicator requirements, selection and definition, procedures for measuring or making estimates, sensitivity, range of values and interactions. Emphasizing the need to use indicators to develop a system of desertification evaluation, this paper outlines the advantages and difficulties of using such an evaluation system.We would like to thank BANCAIXA for its financial support of this study.Peer reviewe
Keratin 8 variants are infrequent in patients with alcohol-related liver cirrhosis and do not associate with development of hepatocellular carcinoma
Abstract Background Keratins 8/18 (K8/K18) are established hepatoprotective proteins and K8/K18 variants predispose to development and adverse outcome of multiple liver disorders. The importance of K8/K18 in alcoholic liver disease as well as in established cirrhosis remains unknown. Methods We analyzed the K8 mutational hot-spots in 261 prospectively followed-up patients with alcoholic cirrhosis (mean follow-up 65 months). PCR-amplified samples were pre-screened by denaturing high-performance liquid chromatography and conspicuous samples were sequenced. Results 67 patients developed hepatocellular carcinoma (HCC) and 133 died. Fourteen patients harbored amino-acid-altering K8 variants (5xG62C, 8xR341H). The presence of K8 variants did not associate with development of HCC (log-rank=0.5) or death (log-rank=0.7) and no significant associations were obtained for the single K8 variants after a correction for multiple testing was performed. Conclusions Keratin variants are expressed in a low percentage of patients with alcoholic cirrhosis and do not influence HCC development. Further studies conducted in larger prospective cohorts are needed to find out whether presence of K8 R341H variant predispose to non-HCC-related liver mortality.</p
Predicting influenza A and 2009 H1N1 influenza in patients admitted to hospital with acute respiratory illness
Objective: To create a clinical decision tool for suspected influenza A (including 2009 H1N1) to facilitate treatment and isolation decisions for patients admitted to hospital with an acute respiratory illness from the emergency department (ED) during a 2009 H1N1 pandemic. Methods: Cross-sectional study conducted in two hospitals in Queensland, Australia. All patients admitted to hospital from the ED between 24 May and 16 August 2009 with an acute respiratory illness were included. All had nasal and throat swabs taken. Data were collected from clinical chart review regarding clinical symptoms, co-morbidities, examination findings, pathology and radiology results. Influenza A status was detected by reverse transcription - PCR assay. Univariate and multivariate regression analyses were performed to identify independent predictors of influenza A status. Results: 346 consecutive patients were identified, of which 106 were positive for 2009 H1N1 influenza; an additional 11 patients were positive for other influenza A viruses. Independent clinical predictors (with points allocated using weighted scoring) for all types of influenza A in patients admitted with acute respiratory illness were: age 18-64 years (2 points); history of fever (2); cough (1); normal level of consciousness (2); C-reactive protein >5 and ≤100 mg/l (2) and normal leucocyte count (1). A clinical score of 5 (presence of two or three predictors) gave a sensitivity of 93% (95% CI 87% to 96%), specificity of 36% (95% CI 30% to 42%), resulting in a negative-predictive value of 91% (95% CI 83% to 95%). Conclusion: A clinical prediction tool was developed that may be able to assist in making appropriate isolation decisions during future 2009 H1N1 outbreaks
Improvement of the commercial quality of chilled Norway lobster (Nephrops norvegicus) stored in slurry ice: Effects of a preliminary treatment with an antimelanosic agent on enzymatic browning
8 páginas, 7 figuras, 2 tablasThe use of slurry ice is gaining increasing importance as an advanced method for the hygienic and efficient chilling and sub-zero storage
of aquatic food products. In this work, this technology was applied as a novel technique for the chilling and storage of Norway lobster
(Nephrops norvegicus) – a crustacean species of high-commercial value – under refrigeration conditions at 1.5 C. In addition, the
effects of a preliminary treatment with 0.5% Na HSO3 on surface browning were evaluated and compared with the results obtained in
control batches not subjected to such treatment. The processing of lobster in slurry ice significantly (p < 0.05) slowed down microbial
spoilage, as determined by the counts of aerobes, psychrotrophs, proteolytic bacteria, and lactose-fermenting Enterobacteriaceae, and
by the formation of volatile amines. Likewise, the autolytic breakdown mechanisms – as determined by the K value – were also significantly
(p < 0.05) inhibited in the slurry ice batch. Remarkably, preliminary treatment with 0.5% sodium metabisulphite permitted better
maintenance of the parameters involved in sensory quality – especially as regards the aspect of the carapace – as compared with nontreated
batches, and allowed a shelf life of 9 days without surpassing the 150 mg/kg legal limit established for this food additive. On
contrast, the non-treated batch stored in slurry ice exhibited a shelf life of 5 days. The combination of technological treatments proposed
in this work – preliminary antimelanosic treatment and storage in slurry ice – may be successfully applied to other fresh and frozen shellfish
species with a view to extending shelf life and to avoiding the legal and toxicological problems derived from current abuse of such
antimelanosic agents to prevent shellfish browning.This work was supported by the Dirección Xeral de I + D + I from the Xunta de Galicia
(Galicia, Spain) (Project PGIDTI02RMA18E).Peer reviewe
Additional file 1: Figure S1. of Prevalence of genetic variants of keratins 8 and 18 in patients with drug-induced liver injury
Identification of the novel variants (A) K8 K393R and (B) K18 D89H. A comparison with wild type (WT) sequences (left panels) reveals the heterozygous nature of the depicted variants. Standard single-letter amino acid abbreviations are used. (PDF 2587Â kb