919 research outputs found
Reactive oxygen species and nitric oxide in viral diseases
Metabolites derived from superoxide (o2 â˘â) and nitric oxide (NOâ˘) play an important role in antimicrobial and antitumoral defense, but may also harm the host. Low levels of such metabolites can also facilitate viral replication because of their mitogenic effects on cells. Most viruses grow better in proliferating cells, and indeed, many viruses induced in their host cell changes similar to those seen early after treatment with mitogenic lectins. Influenza and paramyxoviruses activate in phagocytes the generation of superoxide by a mechanism involving the interaction between the viral surface glycoproteins and the phagocyte's plasma membrane. Interestingly, viruses that activate this host defense mechanism are toxic when injected in the bloodstream of animals. Mice infected with influenza virus undergo oxidative stress. In addition, a wide array of cytokines are formed in the lung, contributing to the systemic effects of influenza. Oxidative stress is seen also in chronic viral infections, such as AIDS and viral hepatitis. Oxidant production in viral hepatitis may contribute to the emergence of hepatocellular carcinoma, a tumor seen in patients after years of chronic inflammation of the liver. Antioxidants and agents that downregulate proinflammatory cytokines and lipid mediators may be a useful complement to specific antiviral drugs in the therapy of viral disease
Standards, training, and guests\u27 perceptions in luxury hotels
Very few hotels are able to consider themselves to be truly luxury. These hotels hold a certain mystique that invites their guests to continually return, no matter what the cost is. While luxury is providing something exclusive that is not found everywhere, it is also becoming more about the experience (Allcock, 2007). Today, luxury hotels are aiming for ultra-luxury, and to do this, service and people factors make a huge difference (Tungate, 2009). The luxury concept includes being exclusive, sophisticated, and indulging your guests (Allcock, 2007). It is crucial that the design and service follow these concepts (Gunter, 2005). These hotels are expected to provide their guests with the best of everything (Sheehan, 2007). Maintaining this level of service is done through understanding guestsâ expectations, setting service standards to meet these expectations, training the staff to follow these service standards, guiding the guestsâ experiences, and identifying and closing service gaps
PrfA activation at the single cell level in Listeria monocytogenes
The human pathogen Listeria monocytogenes is able to transition from environmental saprophyte to facultative intracellular bacteria. In this process, virulence gene expression is controlled by the positive regulatory factor A (PrfA). Recent studies at the single cell level have shown that gene expression in response to stress exposure is stochastic in individual bacteria cells. Current studies applied those general findings to Listeria cells, revealing that PrfA as well is not regulated consistently, but that PrfA activity differs between individual cells. The aim of this study was to elucidate the mechanism by which Listeria regulates PrfA activation at the single cell level and whether this property is heritable or not. A reporter fusion, namely an eGFP sequence, integrated following the PrfA dependent promoter (Phly), was used to visualize the activation after heat stress exposure. Fluorescence activated cell sorting (FACS) was used to distinguish PrfA positive and negative cells. After passaging and sorting PrfA activating versus non-activating cells over several generations, two stable fluorescent phenotypes emerged. A comparison between the genome of the PrfA positive and its parent strain revealed a single-nucleotide polymorphism (SNP) in the CDS of LMRG_02823, as well as a mutation in the 5'UTR of LMRG_00195, both LPXTG family cell wall associated proteins regulated via small RNAs. The link between those mutations and PrfA activation is currently being investigated
A smartphone-based health care chatbot to promote self-management of chronic pain (SELMA) : pilot randomized controlled trial
Background: Ongoing pain is one of the most common diseases and has major physical, psychological, social, and economic impacts. A mobile health intervention utilizing a fully automated text-based health care chatbot (TBHC) may offer an innovative way not only to deliver coping strategies and psychoeducation for pain management but also to build a working alliance between a participant and the TBHC.
Objective: The objectives of this study are twofold: (1) to describe the design and implementation to promote the chatbot painSELfMAnagement (SELMA), a 2-month smartphone-based cognitive behavior therapy (CBT) TBHC intervention for pain self-management in patients with ongoing or cyclic pain, and (2) to present findings from a pilot randomized controlled trial, in which effectiveness, influence of intention to change behavior, pain duration, working alliance, acceptance, and adherence were evaluated.
Methods: Participants were recruited online and in collaboration with pain experts, and were randomized to interact with SELMA for 8 weeks either every day or every other day concerning CBT-based pain management (n=59), or weekly concerning content not related to pain management (n=43). Pain-related impairment (primary outcome), general well-being, pain intensity, and the bond scale of working alliance were measured at baseline and postintervention. Intention to change behavior and pain duration were measured at baseline only, and acceptance postintervention was assessed via self-reporting instruments. Adherence was assessed via usage data.
Results: From May 2018 to August 2018, 311 adults downloaded the SELMA app, 102 of whom consented to participate and met the inclusion criteria. The average age of the women (88/102, 86.4%) and men (14/102, 13.6%) participating was 43.7 (SD 12.7) years. Baseline group comparison did not differ with respect to any demographic or clinical variable. The intervention group reported no significant change in pain-related impairment (P=.68) compared to the control group postintervention. The intention to change behavior was positively related to pain-related impairment (P=.01) and pain intensity (P=.01). Working alliance with the TBHC SELMA was comparable to that obtained in guided internet therapies with human coaches. Participants enjoyed using the app, perceiving it as useful and easy to use. Participants of the intervention group replied with an average answer ratio of 0.71 (SD 0.20) to 200 (SD 58.45) conversations initiated by SELMA. Participantsâ comments revealed an appreciation of the empathic and responsible interaction with the TBHC SELMA. A main criticism was that there was no option to enter free text for the patientsâ own comments.
Conclusions: SELMA is feasible, as revealed mainly by positive feedback and valuable suggestions for future revisions. For example, the participantsâ intention to change behavior or a more homogenous sample (eg, with a specific type of chronic pain) should be considered in further tailoring of SELMA
Quality assurance in transnational higher education : a case study of the tropEd network
Transnational or cross-border higher education has rapidly expanded since the 1980s. Together with that expansion issues on quality assurance came to the forefront. This article aims to identify key issues regarding quality assurance of transnational higher education and discusses the quality assurance of the tropEd Network for International Health in Higher Education in relation to these key issues.; Literature review and review of documents.; From the literature the following key issues regarding transnational quality assurance were identified and explored: comparability of quality assurance frameworks, true collaboration versus erosion of national education sovereignty, accreditation agencies and transparency. The tropEd network developed a transnational quality assurance framework for the network. The network accredits modules through a rigorous process which has been accepted by major stakeholders. This process was a participatory learning process and at the same time the process worked positive for the relations between the institutions.; The development of the quality assurance framework and the process provides a potential example for others
Documentation and interpretation of the petroglyphs of Chichictara, Palpa (Peru), using terrestrial laser scanning and image-based 3D modeling
In Chichictara, southern Peru, petroglyphs cover the surface of around 150 rocks, located in a small valley. The goals of the Chichictara Project are the documentation of the petroglyphs, the dating of them and an understanding of the original social function of the site and its components. The presented research methodology is determined by two properties of petroglyphs: Firstly, they are an artificial intervention into the natural environment. That means their natural and archaeological environment must be decisively included into the interpretation. Secondly, their iconographic value is very high, which means that similarities with other archaeological findings have to be made evident. Thus, the site of Chichictara was documented in 3D by means of laser scanning and photogrammetry. The results will be included into a 3D model of the entire Palpa region and connected with a GIS database containing spatial and archaeological information â the rocks will tell us about the past
Automatic Generation of Coherent Image Galleries in Virtual Reality
With the rapidly increasing size of digitized and born-digital multimedia collections in archives, museums and private collections, manually curating collections becomes a nearly impossible task without disregarding large parts of the collection. In this paper, we propose the use of Self-Organizing Maps (SOMs) to automatically generate coherent image galleries that allow intuitive, user-driven exploration of large multimedia collections in virtual reality (VR). We extend the open-source VR museum VIRTUE to support such exhibitions and apply it on different collections using various image features. A successful pilot test took place at the Basel Historical Museum with more than 300 participants
Praomys degraaffi, a new species of Muridae (Mammalia) from central Africa
A new Praomys species from Burundi, Rwanda and Uganda, Praomys degraaffi n. sp., is described in the P. jacksoni species-complex. It occurs at high elevations in montane forests of the Albertine Rift. The new species is compared with P. jacksoni from the same region and with the other species in the P. jacksoni species-complex
Identification of Glaesserella parasuis and Differentiation of Its 15 Serovars Using High-Resolution Melting Assays
Glaesserella parasuis is the etiological agent of Glässerâs disease, which is associated with polyserositis and arthritis and has a significant impact on the economy of the pig production industry. For the optimal surveillance of this pathogen, as well as for the investigation of G. parasuis-associated diseases, it is crucial to identify G. parasuis at the serovar level. In this work, we designed and developed new high-resolution melting (HRM) approaches, namely, the species-specific GPS-HRM1 and two serovar-specific HRM assays (GPS-HRM2 and GPS-HRM3), and evaluated the sensitivity and specificity of the assays. The HRM assays demonstrated good sensitivity, with 12.5 fgâ1.25 pg of input DNA for GPS-HRM1 and 125 fgâ12.5 pg for GPS-HRM2 and GPS-HRM3, as well as a specificity of 100% for the identification of all recognized 15 G. parasuis serovars. Eighteen clinical isolates obtained between 2014 and 2022 in Switzerland were tested by applying the developed HRM assays, which revealed a heterogeneous distribution of serovars 2, 7, 4, 13, 1, and 14. The combination with virulence marker vtaA (virulence-associated trimeric autotransporters) allows for the prediction of potentially virulent strains. The assays are simple to execute and enable a reliable low-cost approach, thereby refining currently available diagnostic tools
Evaluation of New Anti-Infective Drugs for the Treatment of Vascular Access Device-Associated Bacteremia and Fungemia
For clinical trials of anti-infective drugs for the treatment of vascular access device-related bloodstream infections, patients should be identified and enrolled on the basis of current standards for the clinical diagnosis of such infections. To ensure comparability of patients, only those infected with staphylococci and Candida species should be included. A prospective, randomized, double-blind design is recommended. Future protocols may include abbreviated courses of therapy, treatment with combinations of drugs, or a progression from parenteral to oral therapy. Clinical response is judged as cure, failure, or indeterminate response; there is no "improvedâ category. Microbiological response is categorized as eradication, persistence, or relapse and is of paramount importance. Several months of follow-up may be necessary for the detection of late relapses or metastatic infections. This guideline does not apply to studies of bacteremia or fungemia secondary to non-device-related, organ-based primary infections (e.g., pneumonia, urinary tract infection), which should be assessed in relation to the primary disorde
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