19 research outputs found
Einfluss der GBV-C-Infektion auf die HIV-1-Replikation
Das 1995 entdeckte GB-Virus C (GBV-C) gehört als Pegivirus zur Familie der Flaviviridae und ist nichtpathogen. In IndustrielĂ€ndern sind 2 bis 12,5 % der gesunden Bevölkerung und bis zu 45 % der Personen aus Risikokollektiven, z.B. Patienten mit Infektionen mit dem humanen Immundefizienzvirus Typ 1 (HIV-1) oder dem Hepatitis-C-Virus (HCV), virĂ€misch. Die Mehrzahl der klinischen Studien und Metaanalysen zu GBV-C/HIV-1-Koinfektionen zeigten, dass GBV-C mit einem verlangsamten Krankheitsverlauf und einer erhöhten Ăberlebenswahrscheinlichkeit von GBV-C/HIV-1-koinfizierten Patienten korreliert. In der Hemophilia Growth and Development Study konnte dieser Effekt bei GBV-C/HCV-/HIV-1-infizierten Kindern und Jugendlichen jedoch nur bedingt nachgewiesen werden. DafĂŒr wurde ein Zusammenhang zwischen einer GBV-C/HCV-Koinfektion und dem Ausheilen der HCV-Infektion beobachtet und in einer weiteren Patientenkohorte aus der Anti-D-Studie bestĂ€tigt. GBV-C/HCV-koinfizierte Patienten haben schlechtere Chancen, die HCV-Infektion auszuheilen. Der Einfluss von GBV-C auf die HIV-1-Replikation wurde in Zellkulturexperimenten untersucht. Es zeigte sich, dass sich die verschiedenen GBV-C-Isolate hinsichtlich ihrer inhibitorischen Kompetenz unterschieden. Folgende mögliche Ursachen wurden untersucht: 1.) die IRES-AktivitĂ€t als Indikator fĂŒr die Translationseffizienz, 2.) die NS5A-Sequenz des in der Literatur beschriebenen HIV-1-inhibitorisch aktiven 16mer-Peptids sowie 3.) die E2-Sequenz und die HIV-1-inhibitorische Wirkung von 18mer-E2-Peptiden. Es konnten weder Unterschiede in der IRES-AktivitĂ€t noch in der NS5A-Sequenz zwischen den unterschiedlich inhibitorisch-kompetenten GBV-C-Isolaten nachgewiesen werden. Im E2-Protein hingegen wurden zwei fĂŒr alle HIV-1-nichtinhibitorischen GBV-C-Isolate einheitliche Mutationen, E143K/H und T204A, identifiziert. Diese könnten eine Ursache fĂŒr die Varianz in der FĂ€higkeit, HIV-1 zu inhibieren, darstellen. Die Mutation an Position E143 ist an der OberflĂ€che des nativen E2-Proteins exponiert und spielt möglicherweise im Hemmmechanismus eine wichtige Rolle. Hinweise darauf gaben die Untersuchungen mit synthetischen 18mer-Peptiden, von denen das Peptid mit dem gröĂten inhibitorischen Potenzial die AminosĂ€ure an Position 143 beinhaltete. Eine mögliche Theorie des Wirkmechanismus des E2-Proteins wĂ€re wie folgt denkbar: Das E2-Protein interagiert ĂŒber eine DomĂ€ne um die AminosĂ€ure E143 mit dem gp41 des HIV-1, verhindert somit die Fusion von Virus- und Zellmembran und in der Folge den Eintritt des HIV-1 in die Zielzelle
Intravenous versus epidural analgesia to reduce the incidence of gastrointestinal complications after elective pancreatoduodenectomy (the PAKMAN trial, DRKS 00007784): study protocol for a randomized controlled trial
Background: Despite substantial improvements in surgical and anesthesiological practices leading to decreased mortality of less than 5Â % at high-volume centers, pancreatic surgery is still associated with high morbidity rates of up to 50Â %. Attention is increasingly directed toward the optimization of perioperative management to reduce complications and enhance postoperative recovery. Currently, two different strategies for postoperative pain management after pancreatoduodenectomy are being routinely used: patient-controlled intravenous analgesia and thoracic epidural analgesia. Evidence is lacking to assess which strategy entails fewer postoperative complications. Methods/design: The PAKMAN trial is designed as an adaptive, pragmatic, randomized, controlled, multicenter, open-label, superiority trial with two parallel study groups. A total of 370 patients scheduled for elective pancreatoduodenectomy will be randomized after giving written informed consent, and 278 patients are needed for analysis. Patients with chronic pancreatitis, severe chronic obstructive pulmonary disease (COPD), American Society of Anesthesiologists (ASA) physical status classificationââ„âIV, or chronic pain syndrome will be excluded. The group A intervention includes intraoperative general anesthesia and postoperative patient-controlled intravenous analgesia; the group B intervention comprises combined intraoperative general anesthesia and epidural analgesia with postoperative epidural analgesia. The primary endpoint of this trial is a composite of the gastrointestinal complications (delayed gastric emptying, pancreatic fistula, biliary leak, gastrointestinal bleeding, and postoperative ileus) up to postoperative day 30. The aim is to investigate whether the frequency of gastrointestinal complications following pancreatoduodenectomy can be reduced by 15Â % using postoperative, patient-controlled intravenous analgesia compared with epidural analgesia. Discussion: Several previous studies investigating the two different strategies for postoperative pain management have mainly focused on their effectiveness in pain control. However, the PAKMAN trial is the first to compare them with regard to their impact on the surgical endpoint âpostoperative gastrointestinal complicationsâ after pancreatoduodenectomy. Trial registration: German Clinical Trials Register, DRKS0000778
Prospective multicentre cohort study of patient-reported outcomes and complications following major abdominal neoplastic surgery (PATRONUS) â study protocol for a CHIR-Net student-initiated German medical audit study (CHIR-Net SIGMA study)
Background: One of the most important aspects of designing a clinical trial is selecting appropriate outcomes. Patient-reported outcomes (PROs) can provide a personal assessment of the burden and impact of a malignant disease and its treatment. PROs comprise a wide range of outcomes including basic clinical symptom scores and complex metrics such as health-related quality of life (HRQoL). There is limited data on how postoperative complications following cancer surgery affect symptoms and HRQoL. For this reason the primary aim of the PATRONUS study is to investigate how perioperative complications affect cancer-related symptoms and HRQoL in patients undergoing abdominal cancer surgery. The PATRONUS study is designed and will be initiated and conducted by medical students under the direct supervision of clinician scientists based on the concept of inquiry-based learning.
Methods: PATRONUS is a non-interventional prospective multicentre cohort study. Patients undergoing elective oncological abdominal surgery will be recruited at regional centres of the clinical network of the German Surgical Society (CHIR-Net) and associated hospitals. A core set of 12 cancer associated symptoms will be assessed via the PRO version of the Common Terminology Criteria for Adverse Events. The cancer-specific HRQoL will be measured via the computerised adaptive testing version of the European Organisation for Research and Treatment of Cancer (EORTC) QLQ-C30. PROs will be measured eight times over a period of six months. The short-term clinical outcome measure is the rate of postoperative complications (grade II to V) within 30Â days according to the Clavien-Dindo classification. The long-term clinical outcome is overall survival within six months postoperative.
Discussion: PATRONUS will provide essential insights into the patientsâ assessment of their well-being and quality of life in direct relation to clinical outcome parameters following abdominal cancer surgery. Furthermore, PATRONUS will investigate the feasibility of multicentre student-led clinical research.
Trial registration
German Clinical Trials Register: DRKS00013035 (registered on October 26, 2017).
Universal Trial Number (UTN): U1111â1202-8863
Intravenous versus epidural analgesia to reduce the incidence of gastrointestinal complications after elective pancreatoduodenectomy (the PAKMAN trial, DRKS 00007784): study protocol for a randomized controlled trial
Einfluss der GBV-C-Infektion auf die HIV-1-Replikation
Das 1995 entdeckte GB-Virus C (GBV-C) gehört als Pegivirus zur Familie der Flaviviridae und ist nichtpathogen. In IndustrielĂ€ndern sind 2 bis 12,5 % der gesunden Bevölkerung und bis zu 45 % der Personen aus Risikokollektiven, z.B. Patienten mit Infektionen mit dem humanen Immundefizienzvirus Typ 1 (HIV-1) oder dem Hepatitis-C-Virus (HCV), virĂ€misch. Die Mehrzahl der klinischen Studien und Metaanalysen zu GBV-C/HIV-1-Koinfektionen zeigten, dass GBV-C mit einem verlangsamten Krankheitsverlauf und einer erhöhten Ăberlebenswahrscheinlichkeit von GBV-C/HIV-1-koinfizierten Patienten korreliert. In der Hemophilia Growth and Development Study konnte dieser Effekt bei GBV-C/HCV-/HIV-1-infizierten Kindern und Jugendlichen jedoch nur bedingt nachgewiesen werden. DafĂŒr wurde ein Zusammenhang zwischen einer GBV-C/HCV-Koinfektion und dem Ausheilen der HCV-Infektion beobachtet und in einer weiteren Patientenkohorte aus der Anti-D-Studie bestĂ€tigt. GBV-C/HCV-koinfizierte Patienten haben schlechtere Chancen, die HCV-Infektion auszuheilen. Der Einfluss von GBV-C auf die HIV-1-Replikation wurde in Zellkulturexperimenten untersucht. Es zeigte sich, dass sich die verschiedenen GBV-C-Isolate hinsichtlich ihrer inhibitorischen Kompetenz unterschieden. Folgende mögliche Ursachen wurden untersucht: 1.) die IRES-AktivitĂ€t als Indikator fĂŒr die Translationseffizienz, 2.) die NS5A-Sequenz des in der Literatur beschriebenen HIV-1-inhibitorisch aktiven 16mer-Peptids sowie 3.) die E2-Sequenz und die HIV-1-inhibitorische Wirkung von 18mer-E2-Peptiden. Es konnten weder Unterschiede in der IRES-AktivitĂ€t noch in der NS5A-Sequenz zwischen den unterschiedlich inhibitorisch-kompetenten GBV-C-Isolaten nachgewiesen werden. Im E2-Protein hingegen wurden zwei fĂŒr alle HIV-1-nichtinhibitorischen GBV-C-Isolate einheitliche Mutationen, E143K/H und T204A, identifiziert. Diese könnten eine Ursache fĂŒr die Varianz in der FĂ€higkeit, HIV-1 zu inhibieren, darstellen. Die Mutation an Position E143 ist an der OberflĂ€che des nativen E2-Proteins exponiert und spielt möglicherweise im Hemmmechanismus eine wichtige Rolle. Hinweise darauf gaben die Untersuchungen mit synthetischen 18mer-Peptiden, von denen das Peptid mit dem gröĂten inhibitorischen Potenzial die AminosĂ€ure an Position 143 beinhaltete. Eine mögliche Theorie des Wirkmechanismus des E2-Proteins wĂ€re wie folgt denkbar: Das E2-Protein interagiert ĂŒber eine DomĂ€ne um die AminosĂ€ure E143 mit dem gp41 des HIV-1, verhindert somit die Fusion von Virus- und Zellmembran und in der Folge den Eintritt des HIV-1 in die Zielzelle
Diagnostic Value of Anti-GBV-C Antibodies in HIV-Infected Patients
The beneficial effect of co-infection by GB virus C (GBV-C) in the course of the disease in human immunodeficiency virus (HIV)-infected patients has been described, although its mechanism of action is yet to be determined. The role of anti-GBV-C antibodies in HIV-infected patients also remains unknown. At present, there are no commercial systems to detect specific markers of GBV-C infection. The research presented follows our previous work from which we obtained chimeric molecules formed by two domains of different GBV-C proteins with good sensitivity/specificity balances in the detection of anti-GBV-C antibodies in hemodialyzed and chronic hepatitis patient samples. It has been investigated the ability of the synthetic peptides to recognize specific anti-GBV-C antibodies in HIV and HCV/HIV co-infected patients by a peptide-based ELISA immunoassay. The results showed that human immunodeficiency virus-infected patients have a significantly higher frequency of anti-GBV-C antibodies than healthy controls. A comparison between HCV+/HIV+ and HCVâ/HIV+ was analyzed. Although a higher percentage of HCV/HIV-positive sera were positive for antibodies against GBV-C peptides, the difference was not significant. The presence of anti-GBV-C antibodies could represent a good marker of exposure to GBV-C in HIV-infected patients to facilitate a further analysis of the effect of this exposure in the progression of illness caused by HIV infection.This work was funded by Grants CTQ2009-13969-CO2-01/BQU from the Ministerio de Ciencia e InnovaciĂłn and PIE-I3(200880I081) from Consejo Superior de Investigaciones CientĂficas (CSIC), Spain. LF is a recipient of a FPI grant from the Ministerio de Ciencia, Spain.Peer reviewe
Encouraging student-driven clinical research in Germany: the CHIR-Net SIGMA network
Evidence should define and guide modern clinical care, yet many relevant questions in surgical practice remain unconfirmed by substantial data. Evidence-based medicine requires both the implementation of its principles in day-to-day work and the acquisition of new evidence preferably by randomized controlled trials and systematic reviews. Meaningful clinical research, however, is challenging to conduct, and its overall infrastructure in Germany was, until recently, considered poor compared to other leading countries. Although this has been significantly improved after the establishment of the Study Center of the German Surgical Society (SDGC) and the surgical clinical trial network CHIR-Net, limited focus has been put on the training, teaching, and recruitment of medical students to become competent clinical researchers and clinician scientists. To ensure continuing comprehensive clinical research in surgery, CHIR-Net aims to establish a student-driven multicenter research network in Germany, which is embedded in both the national CHIR-Net and the pan-European and international frameworks. Student-Initiated German Medical Audits (SIGMA) is a product of the strong collaboration between clinical scientists and medical trainees, enabling students to contribute to high-quality clinical trials. Additionally, participants are offered extensive training to support the next generation of research-active clinicians. Starting on 2018, SIGMA will perform its first multicenter observational study in Germany
Efficacy of different spinal cord stimulation paradigms for the treatment of chronic neuropathic pain (PARS-trial): study protocol for a double-blinded, randomized, and placebo-controlled crossover trial
Background!#!Spinal cord stimulation (SCS) is an effective method to treat neuropathic pain; however, it is challenging to compare different stimulation modalities in an individual patient, and thus, it is largely unknown which of the many available SCS modalities is most effective. Specifically, electrodes leading out through the skin would have to be consecutively connected to different, incompatible SCS devices and be tested over a time period of several weeks or even months. The risk of wound infections for such a study would be unacceptably high and blinding of the trial difficult. The PARS-trial seizes the capacity of a new type of wireless SCS device, which enables a blinded and systematic intra-patient comparison of different SCS modalities over extended time periods and without increasing wound infection rates.!##!Methods!#!The PARS-trial is designed as a double-blinded, randomized, and placebo-controlled multi-center crossover study. It will compare the clinical effectiveness of the three most relevant SCS paradigms in individual patients. The trial will recruit 60 patients suffering from intractable neuropathic pain of the lower extremities, who have been considered for SCS therapy and were already implanted with a wireless SCS device prior to study participation. Over a time period of 35âdays, patients will be treated consecutively with three different SCS paradigms ('burst,' '1âkHz,' and '1.499âkHz') and placebo stimulation. Each SCS paradigm will be applied for 5âdays with a washout period of 70âh between stimulation cycles. The primary endpoint of the study is the level of pain self-assessment on the visual analogue scale after 5âdays of SCS. Secondary, exploratory endpoints include self-assessment of pain quality (as determined by painDETECT questionnaire), quality of life (as determined by Quality of Life EQ-5D-5L questionnaire), anxiety perception (as determined by the Hospital Anxiety and Depression Scale), and physical restriction (as determined by the Oswestry Disability Index).!##!Discussion!#!Combining paresthesia-free SCS modalities with wireless SCS offers a unique opportunity for a blinded and systematic comparison of different SCS modalities in individual patients. This trial will advance our understanding of the clinical effectiveness of the most relevant SCS paradigms.!##!Trial registration!#!German Clinical Trials Register, DRKS00018929 . Registered on 14 January 2020
Effect of Synthetic Peptides Belonging to E2 Envelope Protein of GB Virus C on Human Immunodeficiency Virus Type 1 Infection
The use of synthetic peptides as HIV-1 inhibitors has been subject to research over recent years. Although the initial therapeutic attempts focused on HIV-coded enzymes, structural HIV proteins and, more specifically, the mechanisms that the virus uses to infect and replicate are now also considered therapeutic targets. The interest for viral fusion and entry inhibitors is growing significantly, given that they are applicable in combined therapies or when resistance to other antiretroviral drugs is seen and that they act before the virus enters the cell. The 124 synthetic sequences of the GBV-C E2 envelope protein have been obtained by SPPS. The interaction of certain GBV-C peptide sequences with the HIV-1 fusion peptide has been proven through the use of biophysical techniques. We also show how GBV-C E2 domains notably decrease cellular membrane fusion and interfere with the HIV-1 infectivity in a dose-dependent manner, highlighting their potential utility in future anti-HIV-1 therapies.This work was funded by Grants CTQ2006-15396-CO2-01/BQU and CTQ2009-13969-CO2-01/BQU from the Ministerio de Ciencia e InnovaciĂłn, Spain. E.H. is the recipient of predoctoral grant (JAE program, CSIC, Spain). We also acknowledge Dr. Rafel Prohens (Scientific Parc of Barcelona), Dr. Ricardo Gutierrez (Pompeu Fabra University), and Dr. JuliĂ Blanco (FundaciĂł IRSI Caixa) for the discussion of ITC, SPR, and inhibition of cellâcell binding studies, respectively.
The following reagent was obtained through the NIH AIDS Research and Reference Reagent Program, Division of AIDS, NIAID, NIH: HIV-1 IIIB C34 peptide from DAIDS, NIAID.Peer reviewe