164 research outputs found

    One special question to start with: can HIF/NFkB be a target in inflammation?

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    Hypoxia and Inflammation are strictly interconnected with important consequences at clinical and therapeutic level. While cell and tissue damage due to acute hypoxia mostly leads to cell necrosis, in chronic hypoxia, cells that are located closer to vessels are able to survive adapting their phenotype through the expression of a number of genes, including proinflammatory receptors for alarmins. These receptors are activated by alarmins released by necrotic cells and generate signals for master transcription factors such as NFkB, AP1, etc. which control hundreds of genes for innate immunity and damage repair. Clinical consequences of chronic inflammatory reparative response activation include cell and tissue remodeling, damage in the primary site and, the systemic involvement of distant organs and tissues. Thus every time a tissue environment becomes stably hypoxic, inflammation can be activated followed by chronic damage and cell death or repair with vessel proliferation and fibrosis. This pathway can occur in cancer, myocardial infarction and stroke, diabetes, obesity, neurodegenerative diseases, chronic and autoimmune diseases and age-related diseases. Interestingly, proinflammatory gene expression can be observed earlier in hypoxic tissue cells and, in addition, in activated resident or recruited leukocytes. Herewith, the reciprocal relationships between hypoxia and inflammation will be shortly reviewed to underline the possible therapeutic targets to control hypoxia-related inflammation in a number of epidemiologically important human diseases and conditions

    Sparse Coding Predicts Optic Flow Specificities of Zebrafish Pretectal Neurons

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    Zebrafish pretectal neurons exhibit specificities for large-field optic flow patterns associated with rotatory or translatory body motion. We investigate the hypothesis that these specificities reflect the input statistics of natural optic flow. Realistic motion sequences were generated using computer graphics simulating self-motion in an underwater scene. Local retinal motion was estimated with a motion detector and encoded in four populations of directionally tuned retinal ganglion cells, represented as two signed input variables. This activity was then used as input into one of two learning networks: a sparse coding network (competitive learning) and backpropagation network (supervised learning). Both simulations develop specificities for optic flow which are comparable to those found in a neurophysiological study (Kubo et al. 2014), and relative frequencies of the various neuronal responses are best modeled by the sparse coding approach. We conclude that the optic flow neurons in the zebrafish pretectum do reflect the optic flow statistics. The predicted vectorial receptive fields show typical optic flow fields but also "Gabor" and dipole-shaped patterns that likely reflect difference fields needed for reconstruction by linear superposition.Comment: Published Conference Paper from ICANN 2018, Rhode

    Torsade de pointes caused by polypharmacy and substance abuse in a patient with human immunodeficiency virus

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    Drug-induced QT prolongation is a potentially dangerous adverse effect of some medication combinations. When QT prolongation progresses to torsade de pointes, life-threatening or fatal outcomes may result. A 57-year-old man with a history of human immunodeficiency syndrome on abacavir, nevirapine, tenofovir, voriconazole, and methadone presented to the emergency department with a chief complaint of new-onset seizures. The physical exam was unremarkable. The electrocardiogram demonstrated sinus bradycardia and a prolonged QTc interval of 690 ms. In the emergency department, he had several episodes of torsade de pointes (TdP) and ventricular tachycardia that resolved spontaneously. These episodes were accompanied by an alteration in mentation and generalized twitching. Magnesium and amiodarone were effective in terminating the dysrhythmia. The patient had multiple risk factors for prolonged QT syndrome including human immunodeficiency virus infection, methadone therapy, and polypharmacy leading to potential drug interactions. Physicians must be aware of multidrug interactions potentiating QT prolongation and leading to torsade de pointes

    Predator Mimicry: Metalmark Moths Mimic Their Jumping Spider Predators

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    Cases of mimicry provide many of the nature's most convincing examples of natural selection. Here we report evidence for a case of predator mimicry in which metalmark moths in the genus Brenthia mimic jumping spiders, one of their predators. In controlled trials, Brenthia had higher survival rates than other similarly sized moths in the presence of jumping spiders and jumping spiders responded to Brenthia with territorial displays, indicating that Brenthia were sometimes mistaken for jumping spiders, and not recognized as prey. Our experimental results and a review of wing patterns of other insects indicate that jumping spider mimicry is more widespread than heretofore appreciated, and that jumping spiders are probably an important selective pressure shaping the evolution of diurnal insects that perch on vegetation

    Targeted calcium influx boosts cytotoxic T lymphocyte function in the tumour microenvironment

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    Adoptive cell transfer utilizing tumour-targeting cytotoxic T lymphocytes (CTLs) is one of the most effective immunotherapies against haematological malignancies, but significant clinical success has not yet been achieved in solid tumours due in part to the strong immunosuppressive tumour microenvironment. Here, we show that suppression of CTL killing by CD4+CD25+Foxp+ regulatory T cell (Treg) is in part mediated by TGFβ-induced inhibition of inositol trisphosphate (IP3) production, leading to a decrease in T cell receptor (TCR)-dependent intracellular Ca2+ response. Highly selective optical control of Ca2+ signalling in adoptively transferred CTLs enhances T cell activation and IFN-γ production in vitro, leading to a significant reduction in tumour growth in mice. Altogether, our findings indicate that the targeted optogenetic stimulation of intracellular Ca2+ signal allows for the remote control of cytotoxic effector functions of adoptively transferred T cells with outstanding spatial resolution by boosting T cell immune responses at the tumour sites

    Glomerular filtration rate and prevalence of chronic kidney disease in Wilms’ tumour survivors

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    Glomerular filtration rate (GFR) was evaluated in 32 Wilms’ tumour survivors (WTs) in a cross-sectional study using 99 Tc-diethylene triamine pentaacetic acid (99 Tc-DTPA) clearance, the Schwartz formula, the new Schwartz equation for chronic kidney disease (CKD), cystatin C serum concentration and the Filler formula. Kidney damage was established by beta-2-microglobulin (B-2-M) and albumin urine excretion, urine sediment and ultrasound examination. Blood pressure was measured. No differences were found between the mean GFR in 99 Tc-DTPA and the new Schwartz equation for CKD (91.8 ± 11.3 vs. 94.3 ± 10.2 ml/min/1.73 m2 [p = 0.55] respectively). No differences were observed between estimated glomerular filtration rate (eGFR) using the Schwartz formula and the Filler formula either (122.3 ± 19.9 vs. 129.8 ± 23.9 ml/min/1.73 m2 [p = 0.28] respectively). Increased urine albumin and B-2-M excretion, which are signs of kidney damage, were found in 7 (22%) and 3 (9.4%) WTs respectively. Ultrasound signs of kidney damage were found in 14 patients (43%). Five patients (15.6%) had more than one sign of kidney damage. Eighteen individuals (56.25%) had CKD stage I (10 with signs of kidney damage; 8 without). Fourteen individuals (43.75%) had CKD stage II (6 with signs of kidney damage; 8 without). The new Schwartz equation for CKD better estimated GFR in comparison to the Schwartz formula and the Filler formula. Furthermore, the WT survivors had signs of kidney damage despite the fact that GFR was not decreased below 90 ml/min/1.73 m2 with 99 Tc- DTPA

    Workplace violence in a large correctional health servce in New South Wales, Australia: a retrospective review of incident management records

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    BackgroundLittle is known about workplace violence among correctional health professionals. This studyaimed to describe the patterns, severity and outcomes of incidents of workplace violenceamong employees of a large correctional health service, and to explore the help-seekingbehaviours of staff following an incident.MethodsThe study setting was Justice Health, a statutory health corporation established to providehealth care to people who come into contact with the criminal justice system in New SouthWales, Australia. We reviewed incident management records describing workplace violenceamong Justice Health staff. The three-year study period was 1/7/2007-30/6/2010.ResultsDuring the period under review, 208 incidents of workplace violence were recorded. Verbalabuse (71%) was more common than physical abuse (29%). The most (44%) incidents ofworkplace violence (including both verbal and physical abuse) occurred in adult maleprisons, although the most (50%) incidents of physical abuse occurred in a forensic hospital.Most (90%) of the victims were nurses and two-thirds were females. Younger employees andmales were most likely to be a victim of physical abuse. Preparing or dispensing medicationand attempting to calm and/or restrain an aggressive patient were identified as ‘high risk’work duties for verbal abuse and physical abuse, respectively. Most (93%) of the incidents ofworkplace violence were initiated by a prisoner/patient. Almost all of the incidents receivedeither a medium (46%) or low (52%) Severity Assessment Code. Few victims of workplaceviolence incurred a serious physical injury – there were no workplace deaths during the studyperiod. However, mental stress was common, especially among the victims of verbal abuse(85%). Few (6%) victims of verbal abuse sought help from a health professional.ConclusionsAmong employees of a large correctional health service, verbal abuse in the workplace wassubstantially more common than physical abuse. The most incidents of workplace violenceoccurred in adult male prisons. Review of the types of adverse health outcomes experiencedby the victims of workplace violence and the assessments of severity assigned to violentincidents suggests that, compared with health care settings in the community, correctionalsettings are fairly safe places in which to practice

    Tissue-Specific Target Analysis of Disease-Associated MicroRNAs in Human Signaling Pathways

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    MicroRNAs are a large class of post-transcriptional regulators that bind to the 3′ untranslated region of messenger RNAs. They play a critical role in many cellular processes and have been linked to the control of signal transduction pathways. Recent studies indicate that microRNAs can function as tumor suppressors or even as oncogenes when aberrantly expressed. For more general insights of disease-associated microRNAs, we analyzed their impact on human signaling pathways from two perspectives. On a global scale, we found a core set of signaling pathways with enriched tissue-specific microRNA targets across diseases. The function of these pathways reflects the affinity of microRNAs to regulate cellular processes associated with apoptosis, proliferation or development. Comparing cancer and non-cancer related microRNAs, we found no significant differences between both groups. To unveil the interaction and regulation of microRNAs on signaling pathways locally, we analyzed the cellular location and process type of disease-associated microRNA targets and proteins. While disease-associated proteins are highly enriched in extracellular components of the pathway, microRNA targets are preferentially located in the nucleus. Moreover, targets of disease-associated microRNAs preferentially exhibit an inhibitory effect within the pathways in contrast to disease proteins. Our analysis provides systematic insights into the interaction of disease-associated microRNAs and signaling pathways and uncovers differences in cellular locations and process types of microRNA targets and disease-associated proteins

    Exploring Cell Tropism as a Possible Contributor to Influenza Infection Severity

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    Several mechanisms have been proposed to account for the marked increase in severity of human infections with avian compared to human influenza strains, including increased cytokine expression, poor immune response, and differences in target cell receptor affinity. Here, the potential effect of target cell tropism on disease severity is studied using a mathematical model for in-host influenza viral infection in a cell population consisting of two different cell types. The two cell types differ only in their susceptibility to infection and rate of virus production. We show the existence of a parameter regime which is characterized by high viral loads sustained long after the onset of infection. This finding suggests that differences in cell tropism between influenza strains could be sufficient to cause significant differences in viral titer profiles, similar to those observed in infections with certain strains of influenza A virus. The two target cell mathematical model offers good agreement with experimental data from severe influenza infections, as does the usual, single target cell model albeit with biologically unrealistic parameters. Both models predict that while neuraminidase inhibitors and adamantanes are only effective when administered early to treat an uncomplicated seasonal infection, they can be effective against more severe influenza infections even when administered late
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