Podcasts about methods here

  • 10PODCASTS
  • 18EPISODES
  • AVG DURATION
  • ?INFREQUENT EPISODES
  • Jun 24, 2023LATEST

POPULARITY

20172018201920202021202220232024


Best podcasts about methods here

Latest podcast episodes about methods here

PaperPlayer biorxiv neuroscience
Aberrant type 2 dopamine receptor availability in criminal psychopathy

PaperPlayer biorxiv neuroscience

Play Episode Listen Later Jun 24, 2023


Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2023.06.21.545877v1?rss=1 Authors: Lukkarinen, L., Tuisku, J., Sun, L., Helin, S., Karlsson, H., Venetjoki, N., Salomaa, M., Rautio, P., Hirvonen, J., Lauerma, H., Tiihonen, J., Nummenmaa, L. Abstract: Background: Psychopathy is characterized by antisocial behavior, poor behavioral control and lacking empathy, and structural alterations in the corresponding neural circuits. Molecular brain basis of psychopathy remains poorly characterized. Methods: Here we studied type 2 dopamine receptor (D2R) and mu-opioid receptor (MOR) availability in convicted violent offenders with high psychopathic traits (n=11) and healthy matched controls (n=19) using positron emission tomography (PET). D2R were measured with radioligand [11C]raclopride and MORs with radioligand [11C]carfentanil. Results: Psychopathic subjects had lowered D2R availability in caudate and putamen, and D2R striatal availability was also associated with degree of psychopathic traits in this prisoner sample. No group differences were found in MOR availability, although in the prisoner sample, psychopathic traits were negatively correlated with MOR availability amygdala and nucleus accumbens. Conclusions: We conclude that D2R signaling could be the putative neuromolecular pathway for psychopathy, whereas evidence for the aberrant MOR system is more limited. Copy rights belong to original authors. Visit the link for more info Podcast created by Paper Player, LLC

PaperPlayer biorxiv neuroscience
Histone H3 serotonylation dynamics in dorsal raphe nucleus contribute to stress-induced gene expression and behavior

PaperPlayer biorxiv neuroscience

Play Episode Listen Later May 4, 2023


Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2023.05.04.539464v1?rss=1 Authors: Al-Kachak, A., Fulton, S. L., Farrelly, L. A., Lepack, A. E., Bastle, R. M., Kong, L., Cathomas, F., Newman, E. L., Menard, C., Ramakrishnan, A., Chan, J. C., Safovich, P., Lyu, Y., Covington, H. E., Shen, L., Gleason, K., Tamminga, C. A., Russo, S. J., Maze, I. Abstract: Background: Major depressive disorder (MDD) is a debilitating illness that affects millions of individuals worldwide. While chronic stress increases incidence levels of MDD, stress-mediated disruptions in brain function that precipitate the disorder remain elusive. Serotonin-associated antidepressants (ADs) remain the first line of therapy for many with MDD, yet low remission rates and delays between treatment and symptomatic alleviation have prompted skepticism regarding precise roles for serotonin in the precipitation of MDD. Our group recently demonstrated that serotonin epigenetically modifies histone proteins (H3K4me3Q5ser) to regulate transcriptional permissiveness in brain. However, this phenomenon has not yet been explored following stress and/or AD exposures. Methods: Here, we employed a combination of genome-wide (ChIP-seq, RNA-seq) and western blotting analyses in dorsal raphe nucleus (DRN) of male and female mice exposed to chronic social defeat stress to examine the impact of stress exposures on H3K4me3Q5ser dynamics in DRN, as well as associations between the mark and stress-induced gene expression. Stress-induced regulation of H3K4me3Q5ser levels were also assessed in the context of AD exposures, and viral-mediated gene therapy was employed to manipulate H3K4me3Q5ser levels to examine the impact of reducing the mark in DRN on stress-associated gene expression and behavior. Results: We found that H3K4me3Q5ser plays important roles in stress-mediated transcriptional plasticity in DRN. Mice exposed to chronic stress displayed dysregulated dynamics of H3K4me3Q5ser in DRN, and viral-mediated attenuation of these dynamics rescued stress-mediated gene expression programs and behavior. Conclusions: These findings establish a neurotransmission-independent role for serotonin in stress-associated transcriptional and behavioral plasticity in DRN. Copy rights belong to original authors. Visit the link for more info Podcast created by Paper Player, LLC

PaperPlayer biorxiv neuroscience
Activation of prefrontal parvalbumin interneurons ameliorates treatment-resistant working memory deficit even under continuous antipsychotic treatment in a mouse model of schizophrenia

PaperPlayer biorxiv neuroscience

Play Episode Listen Later Mar 1, 2023


Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2023.02.27.530344v1?rss=1 Authors: Arime, Y., Saitoh, Y., Ishikawa, M., Kamiyoshihara, C., Uchida, Y., Fujii, K., Takao, K., Akiyama, K., Ohkawa, N. Abstract: BACKGROUND: One of the critical unmet medical needs in schizophrenia is a remedy for cognitive deficits. However, the neural circuit mechanisms of them remain unresolved. In addition, despite the patients with schizophrenia cannot stop taking antipsychotics due to a high rate of discontinuation-induced relapse, previous studies using animal models of schizophrenia have not considered these clinical situations. METHODS: Here, we employ multi-dimensional approaches, including histological analysis in the prelimbic cortex, LC-MS/MS-based in vivo dopamine D2 receptor occupancy analysis for antipsychotic drugs, in vivo calcium imaging and behavioral analyses of mice using chemogenetic manipulation, to investigate neural mechanisms and potential therapeutic interventions for working memory deficit in a mouse model with chronic phencyclidine (PCP) administration that resembles the schizophrenia symptomatology. RESULTS: Chronic PCP administration led to abnormalities in excitatory and inhibitory synapses, including dendritic spines of pyramidal neurons, vesicular glutamate transporter 1 (VGLUT1) positive terminals, and parvalbumin (PV) positive GABAergic interneurons, in layer 2-3 of the prelimbic cortex. Continuous olanzapine, which achieved a sustained therapeutic window of dopamine D2 receptor occupancy (60-80%) in the striatum, did not affect these synaptic abnormalities and working memory deficit in the PCP-treated mice. We found that the selective prelimbic PV activation, using hM3D(Gq)-DREADD system confirmed by in vivo calcium imaging, restored working memory deficit, even under continuous olanzapine treatment. CONCLUSIONS: Our study raises a possibility that intervention in prefrontal PV neurons leads to an add-on therapy to antipsychotics targeting amelioration of treatment-resistant cognitive deficits in schizophrenia. Copy rights belong to original authors. Visit the link for more info Podcast created by Paper Player, LLC

PaperPlayer biorxiv cell biology
Apo- and holo- transferrin differentially interact with ferroportin and hephaestin to regulate iron release at the blood-brain barrier

PaperPlayer biorxiv cell biology

Play Episode Listen Later Jan 10, 2023


Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2023.01.10.522344v1?rss=1 Authors: Baringer, S. L., Palsa, K., Simpson, I. A., Connor, J. R. Abstract: Background: Apo- (iron free) and holo- (iron bound) transferrin (Tf) participate in precise regulation of brain iron uptake at endothelial cells of the blood-brain barrier. Apo-Tf indicates an iron deficient environment and stimulates iron release, while holo-Tf indicates an iron sufficient environment and suppresses additional iron release. Free iron is exported through ferroportin, with hephaestin as an aid to the process. Until now, the molecular mechanism of apo- and holo-Tfs influence on iron release was largely unknown. Methods: Here we use a variety of cell culture techniques, including co-immunoprecipitation and proximity ligation assay, in iPSC-derived endothelial cells and HEK 293 cells to investigate the mechanism of apo- and holo-Tfs influence over iron release. We placed our findings in physiological context by further deciphering how hepcidin played a role in this mechanism as well. Results: We demonstrate that holo-Tf induces the internalization of ferroportin through the established ferroportin degradation pathway. Furthermore, holo-Tf directly binds to ferroportin, whereas apo-Tf directly binds to hephaestin. Only pathological levels of hepcidin disrupt the interaction between holo-Tf and ferroportin, and no amount of hepcidin disrupts the interaction between apo-Tf and hephaestin. The disruption of the holo-Tf and ferroportin interaction by hepcidin is due to hepcidins ability to rapidly internalize ferroportin compared to holo-Tf. Conclusions: These novel findings provide a molecular mechanism for apo- and holo-Tf regulation of iron release from endothelial cells. They further demonstrate how hepcidin impacts these protein-protein interactions, and offer a model for how holo-Tf and hepcidin corporate to suppress iron release. We have established a more thorough understanding of the mechanisms behind iron release regulation with great clinical impact for a variety of neurological conditions in which iron release is dysregulated. Copy rights belong to original authors. Visit the link for more info Podcast created by Paper Player, LLC

PaperPlayer biorxiv neuroscience
Functional gradients reveal altered functional segregation in patients with amnestic mild cognitive impairment and Alzheimer' s disease

PaperPlayer biorxiv neuroscience

Play Episode Listen Later Nov 16, 2022


Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2022.11.16.516698v1?rss=1 Authors: He, Y., Li, Q., Fu, Z., Zeng, D., Han, Y., Li, S. Abstract: Background: Alzheimer's disease (AD) and amnestic mild cognitive impairment (aMCI) are associated with disrupted functional organization in brain networks, yet the finer changes in the topological organization in aMCI and AD remain to be investigated. Connectome gradients are a new tool representing brain functional topological organization in a low-dimensional space to smoothly capture the human macroscale hierarchy. Methods: Here, we examined altered topological organization in aMCI and AD by connectome gradient mapping. We further quantified functional segregation by gradient dispersion. Then, we systematically compared the alterations observed in aMCI and AD patients with those in normal controls (NCs) in a two-dimensional functional gradient space from both the whole-brain level and module level. Results: Compared with NCs, the first gradient, which described the neocortical hierarchy from unimodal to transmodal regions, showed a distributed and significant suppression in AD patients, while abnormalities were only limited to local regions in aMCI patients. The second gradient showed a decreased pattern in the somatomotor module in both aMCI and AD patients. Furthermore, gradient dispersion showed significant decreases in AD patients at both the global level and module level, whereas this alteration was limited only to limbic areas in aMCI. Notably, we demonstrated that suppressed gradient dispersion in aMCI and AD patients was associated with cognitive scores. Conclusions: Changes in functional gradients could reflect different degrees of altered brain network segregation in aMCI and AD. These findings provide new evidence for altered brain hierarchy in aMCI and AD, which strengthens our understanding of the progressive mechanism of cognitive decline. Copy rights belong to original authors. Visit the link for more info Podcast created by Paper Player, LLC

PaperPlayer biorxiv bioinformatics
TruSight Oncology 500: Enabling Comprehensive Genomic Profiling and Biomarker Reporting with Targeted Sequencing

PaperPlayer biorxiv bioinformatics

Play Episode Listen Later Oct 22, 2020


Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.10.21.349100v1?rss=1 Authors: Zhao, C., Jiang, T., Ju, J. H., Zhang, S., Tao, J., Fu, Y., Lococo, J., Dockter, J., Powlowski, T., Bilke, S. Abstract: Background: As knowledge of mechanisms that drive the development of cancer grows, there has been corresponding growth in therapies specific to a mechanism. While these therapies show improvements in patient outcomes, they can be expensive and are effective only for a subset of patients. These treatments drive interest in research focused on the assignment of cancer therapies based on aberrations in individual genes or biomarkers that assess the broader mutational landscape, including microsatellite instability (MSI) and tumor mutational burden (TMB). Methods: Here we describe the TruSight Oncology 500 (TSO500; Research Use Only) bioinformatics workflow. This tumor-only approach leverages the next-generation sequencing-based assay TSO500 to enable high fidelity determination of DNA variants across 523 cancer-relevant genes, as well as MSI status and TMB in formalin-fixed paraffin-embedded (FFPE) samples. Results: The TSO500 bioinformatic workflow integrates unique molecular identifier (UMI)-based error correction and a dual approach variant filtering strategy that combines statistical modeling of error rates and database annotations to achieve detection of variants with allele frequency approaching 5% with 99.9998% per base specificity and 99% sensitivity in FFPE samples representing a variety of tumor types. TMB determined using the tumor-only workflow of TSO500 correlated well with tumor-normal (N =170, adjusted R2=0.9945) and whole-exome sequencing (N=108, adjusted R2=0.933). Similarly, MSI status determined by TSO500 showed agreement (N=106, 98% agreement) with a MSI-PCR assay. Conclusion: TSO500 is an accurate tumor-only workflow that enables researchers to systematically characterize tumors and identify the next generation of clinical biomarkers. Copy rights belong to original authors. Visit the link for more info

PaperPlayer biorxiv neuroscience
Functional spreading of hyperexcitability induced by human and synthetic intracellular Aβ oligomers

PaperPlayer biorxiv neuroscience

Play Episode Listen Later Oct 17, 2020


Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.10.16.332445v1?rss=1 Authors: Fernandez-Perez, E. J., Munoz, B., Bascunan, D. A., Peters, C., Riffo-Lepe, N. O., Espinoza, M. P., Morgan, P. J., Filippi, C., Bourboulou, R., Sengupta, U., Kayed, R., Epsztein, J., Aguayo, L. G. Abstract: Background: Intracellular amyloid-beta oligomers (iA{beta}o) accumulation and neuronal hyperexcitability are two crucial events at early stages of Alzheimer's disease (AD). However, to date, no mechanism linking them has been reported. Methods: Here, the effects of human AD brain-derived (h-iA{beta}o) and synthetic (iA{beta}o) peptides on synaptic currents and action potential (AP) firing were investigated in hippocampal neurons in vitro, ex vivo and in vivo. Results: Starting from 500 pM, iA{beta}o rapidly increased the frequency of synaptic currents and higher concentrations potentiated the AMPA receptor-mediated current. Both effects were PKC-dependent. Parallel recordings of synaptic currents and nitric oxide (NO)-related fluorescence changes indicated that the increased frequency, related to pre-synaptic release, was dependent on a NO-mediated retrograde signaling. Moreover, increased synchronization in NO production was also observed in neurons neighboring those dialyzed with iA{beta}o, indicating that iA{beta}o can increase network excitability at a distance. Current-clamp recordings suggested that iA{beta}o increased neuronal excitability via AMPA-driven synaptic activity without altering membrane intrinsic properties. Conclusion: These results strongly indicate that iA{beta}o causes functional spreading of hyperexcitability through a synaptic-driven mechanism and offer an important neuropathological significance to intracellular species in the initial stages of AD, which include brain hyperexcitability and seizures. Copy rights belong to original authors. Visit the link for more info

PaperPlayer biorxiv neuroscience
Activated iPSC-microglia from C9orf72 ALSFTD patients exhibit endosomal-lysosomal dysfunction

PaperPlayer biorxiv neuroscience

Play Episode Listen Later Sep 3, 2020


Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.09.03.277459v1?rss=1 Authors: Lorenzini, I., Alsop, E., Levy, J., Gittings, L. M., Rabichow, B. E., Lall, D., Moore, S., Bustos, L., Pevey, R., Burciu, C., Saul, J., McQuade, A., Tzioras, M., Mota, T. A., Logemann, A., Rose, J., Almeida, S., Gao, F.-B., Bowser, R., Spires-Jones, T. L., Blurton-Jones, M., Gendron, T. F., Baloh, R. H., Van Keuren-Jensen, K., Sattler, R. Abstract: Background: A mutation in the C9orf72 gene is the most common genetic mutation of familial and sporadic ALS, as well as familial FTD. While prior studies have focused on elucidating the mechanisms of neuronal dysfunction and neurodegeneration associated with this genetic mutation, the contribution of microglia to disease pathogenesis in the ALS/FTD disease spectrum remains poorly understood. Methods: Here, we generated a new disease model consisting of cultured C9orf72 ALS/FTD patient-derived induced pluripotent stem cells differentiated into microglia (iPSC-MG). We used this model to study the intrinsic cellular and molecular phenotypes of microglia triggered by the C9orf72 gene mutation. Results: We show that C9orf72 ALS/FTD iPSC-MG have a similar transcriptional profile compared to control iPSC-MG, despite the presence of C9orf72-associated phenotypes including reduced C9orf72 protein levels and dipeptide-repeat protein translation. Interestingly, C9orf72 ALS/FTD iPSC-MG exhibit intrinsic dysfunction of phagocytic activity upon exposure to A{beta} or brain synaptoneurosomes and display a heightened inflammatory response. Detailed analysis of the endosomal and lysosomal pathways revealed altered expression of endosomal marker early endosome antigen 1 and lysosomal associated membrane protein 1 in C9orf72 ALS/FTD iPSC-MG, which was confirmed in patient postmortem tissues. Conclusions: These findings demonstrate that unstimulated C9orf72 iPSC-MG mono-cultures share a largely similar transcriptome profile with control microglia, despite the presence of C9orf72 disease phenotypes. The dysfunction of the endosomal-lysosomal pathway as demonstrated by aberrant microglia phagocytosis and engulfment of cellular debris and brain pathogens suggests that disease-related microglia phenotypes are not intrinsic but instead require microglia to be activated. In summary, the C9orf72 iPSC-MG culture system provides a novel human disease model to study the role of microglia in C9orf72 ALS/FTD disease pathogenesis. Copy rights belong to original authors. Visit the link for more info

PaperPlayer biorxiv neuroscience
Maternal immune activation during pregnancy alters early neurobehavioral development in nonhuman primate offspring

PaperPlayer biorxiv neuroscience

Play Episode Listen Later Jul 4, 2020


Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.07.02.185363v1?rss=1 Authors: Vlasova, R. M., Iosif, A.-M., Ryan, A. M., Murai, T., Lesh, T. A., Rowland, D. J., Bennett, J., Hogrefe, C. E., Maddock, R. J., Gandal, M. J., Geschwind, D. H., Schumann, C. M., Van de Water, J., McAllister, A. K., Carter, C. S., Styner, M. A., Amaral, D. G., Bauman, M. D. Abstract: Background: Human epidemiologic studies have implicated exposure to infectious or inflammatory insults during gestation in the etiology of neurodevelopmental disorders. Rodent models of maternal immune activation (MIA) have identified the maternal immune response as the critical link between maternal infection and aberrant brain and behavior development in offspring. The nonhuman primate MIA model provides an opportunity to maximize the translational utility of this model in a species more closely related to humans. Methods: Here we evaluate the effects of MIA on brain and behavioral development in the rhesus monkey (Macaca mulatta). A modified form of the viral mimic, Polyinosinic-polycytidylic acid (PolyIC), was delivered to pregnant rhesus monkeys (n=14) in the late first trimester to stimulate a maternal immune response. Control dams received saline injections at the same gestational time points (n=10) or were untreated (n=4). Results: MIA-treated dams exhibited a strong immune response as indexed by transient increases in sickness behavior, temperature and inflammatory cytokines. MIA-exposed offspring developed species typical milestones and demonstrate subtle changes in early in social development. However, magnetic resonance imaging demonstrated significant gray matter volume reductions in prefrontal and frontal cortices at 6, 12 and 24 months of age. Conclusions: These findings provide new insights into the emergence of neuropathology in MIA-exposed primates and have implications for the pathophysiology of human psychiatric disorders associated with maternal gestational infection. Copy rights belong to original authors. Visit the link for more info

PaperPlayer biorxiv neuroscience
BioID analysis of the cyclin F interactome reveals that ALS-variant cyclin F alters the homeostasis of paraspeckle-associated proteins

PaperPlayer biorxiv neuroscience

Play Episode Listen Later May 1, 2020


Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.04.30.071365v1?rss=1 Authors: Rayner, S. L., Cheng, F., Yang, S., Grima, N., Ke, Y. D., Au, C. G., Morsch, M., De Luca, A., Davidson, J. M., Molloy, M. P., Shi, B., Ittner, L. M., Blair, I., Chung, R. S., Lee, A. Abstract: Background: Previously, we identified missense mutations in CCNF that are causative of familial and sporadic amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). CCNF encodes for the protein cyclin F, a substrate recognition component of the E3-ubiquitin ligase, SCFcyclin F. We have previously shown that mutations in CCNF cause disruptions to overall protein homeostasis; causing a build-up of ubiquitylated proteins (1) as well as defects in autophagic machinery (2). Methods: Here, we have used an unbiased proteomic screening workflow using BioID, as well as standard immunoprecipitations to identify novel interaction partners of cyclin F, identifying the interaction between cyclin F and a series of paraspeckle proteins. The homeostasis of these new cyclin F interaction partners, RBM14, NONO and SFPQ were monitored in primary neurons using immunoblotting. In addition, the homeostasis of RBM14 was compared between control and ALS/FTD patient tissue using standard IHC studies. Results: Using BioID, we found over 100 putative interaction partners of cyclin F and demonstrated that cyclin F closely associates with a number of essential paraspeckle proteins, which are stress-responsive proteins that have recently been implicated in ALS pathogenesis. We further demonstrate that the turnover of these novel binding partners are defective when cyclin F carries an ALS/FTD-causing mutation. In addition the analysis of RBM14 levels in ALS patient post-mortem tissue revealed that RBM14 levels were significantly reduced in post-mortem ALS patient motor cortex and significantly reduced in the neurons of spinal cord tissue. Conclusion: Overall, our data demonstrate that the dysregulation of paraspeckle components may be contributing factors to the molecular pathogenesis of ALS/FTD. Copy rights belong to original authors. Visit the link for more info

Medizin - Open Access LMU - Teil 21/22
Development of a Sensitive Phospho-p70 S6 Kinase ELISA to Quantify mTOR Proliferation Signal Inhibition

Medizin - Open Access LMU - Teil 21/22

Play Episode Listen Later Apr 1, 2013


Background: Drug blood levels can only serve as a surrogate because of the lack of information on the drug's direct pharmacological effects in the individual patient. Measurement of the mammalian target of rapamycin (mTOR) activity dependent on the phosphorylation status of p70 S6 kinase (p70 S6K) offers a practical way for monitoring pharmacodynamic drug activity, with the potential to better assess the state of immunosuppression in individual patients. Material and Methods: Here, we established a novel in vitro model system by treating Jurkat cells and peripheral blood mononuclear cells with different concentrations of sirolimus after stimulation with phorbol 12-myristate 13-acetate. Results: A dose-dependent reduction of the p70 S6K phosphorylation status was demonstrated by Western blot and a newly established enzyme-linked immunosorbent assay (ELISA). Relative phospho-p70 S6K values from ELISA and relative densities from Western blot analysis in peripheral blood mononuclear cells revealed a strong correlation (Spearman correlation coefficient r(s) = 0.7, P = 0.01). Finally, parallel assays confirmed a sirolimus dose-dependent reduction of cytokine production and cell proliferation in the in vitro model. Conclusions: Pharmacodynamic monitoring of mTOR inhibition with a p70 S6K ELISA could guide mTOR inhibitor immunosuppression therapy toward a more individualized therapy. The usage of this technique now has to be evaluated in a clinical series of patients.

Medizin - Open Access LMU - Teil 19/22
Management of EGFR-inhibitor associated rash: a retrospective study in 49 patients

Medizin - Open Access LMU - Teil 19/22

Play Episode Listen Later Jan 1, 2012


Background: In recent years inhibitors directed against the epidermal growth factor receptor (EGFR) have evolved as effective targeting cancer drugs. Characteristic papulopustular exanthemas, often described as acneiform rashes, are the most frequent adverse effect associated with this class of novel cancer drugs and develop in > 90% of patients. Notably, the rash may significantly compromise the patients' quality of life, thereby potentially leading to incompliance as well as dose reduction or even termination of the anti-EGFR therapy. Yet, an effective dermatologic management of cutaneous adverse effects can be achieved. Whereas various case reports, case series or expert opinions on the management of EGFR-inhibitor (EGFRI) induced rashes have been published, data on systematic management studies are sparse. Methods: Here, we present a retrospective, uncontrolled, comparative study in 49 patients on three established regimens for the management of EGFRI-associated rashes. Results: Strikingly, patients' rash severity improved significantly over three weeks of treatment with topical mometason furoate cream, topical prednicarbate cream plus nadifloxacin cream, as well as topical prednicarbate cream plus nadifloxacin cream plus systemic isotretinoin. Conclusions: In summary our results demonstrate that EGFRI-associated rashes can be effectively managed by specific dermatologic interventions. Whereas mild to moderate rashes should be treated with basic measures in combination with topical glucocorticosteroids or combined regiments using glucocorticosteroids and antiseptics/antibiotics, more severe or therapy-resistant rashes are likely to respond with the addition of systemic retinoids.

Medizin - Open Access LMU - Teil 18/22
Relevance of circulating nucleosomes and oncological biomarkers for predicting response to transarterial chemoembolization therapy in liver cancer patients

Medizin - Open Access LMU - Teil 18/22

Play Episode Listen Later Jan 1, 2011


Background: Transarterial chemoembolization (TACE) therapy is an effective locoregional treatment in hepatocellular cancer (HCC) patients. For early modification of therapy, markers predicting therapy response are urgently required. Methods: Here, sera of 50 prospectively and consecutively included HCC patients undergoing 71 TACE therapies were taken before and 3 h, 6 h and 24 h after TACE application to analyze concentrations of circulating nucleosomes, cytokeratin-19 fragments (CYFRA 21-1), alpha fetoprotein (AFP), C-reactive protein (CRP) and several liver biomarkers, and to compare these with radiological response to therapy. Results: While nucleosomes, CYFRA 21-1, CRP and some liver biomarkers increased already 24 h after TACE, percental changes of nucleosome concentrations before and 24 h after TACE and pre- and posttherapeutic values of AFP, gamma-glutamyl-transferase (GGT) and alkaline phosphatase (AP) significantly indicated the later therapy response (39 progression versus 32 no progression). In multivariate analysis, nucleosomes (24 h), AP (24 h) and TACE number were independent predictive markers. The risk score of this combination model achieved an AUC of 81.8% in receiver operating characteristic (ROC) curves and a sensitivity for prediction of non-response to therapy of 41% at 97% specificity, and of 72% at 78% specificity. Conclusion: Circulating nucleosomes and liver markers are valuable tools for early estimation of the efficacy of TACE therapy in HCC patients.

Medizin - Open Access LMU - Teil 17/22
Adjuvant glycerol is not beneficial in experimental pneumococcal meningitis

Medizin - Open Access LMU - Teil 17/22

Play Episode Listen Later Jan 1, 2010


Background: Bacterial meningitis in children causes high rates of mortality and morbidity. In a recent clinical trial, oral glycerol significantly reduced severe neurological sequelae in paediatric meningitis caused by Haemophilus influenzae type b, and a tendency towards a benefit of adjunctive glycerol was seen in pneumococcal meningitis. Methods: Here we examined the effects of glycerol in pneumococcal meningitis of infant rats and adult mice. All animals received ceftriaxone, and glycerol or placebo. Brain damage, hearing loss, and inflammatory parameters were assessed. Results: Clinically and by histopathology, animals treated with glycerol or placebo did not differ. While both groups showed equally high levels of matrix metalloproteinase-9 at 24 h after infection, a significant difference in favour of glycerol was observed at 40 h after infection. However, this difference in matrix metalloproteinase-9 in late disease did not result in an improvement of histopathologic parameters. Conclusion: No benefit of adjunctive glycerol was found in these models of pneumococcal meningitis.

Medizin - Open Access LMU - Teil 16/22
Incidence and classification of pediatric diffuse parenchymal lung diseases in Germany

Medizin - Open Access LMU - Teil 16/22

Play Episode Listen Later Jan 1, 2009


Background: Diffuse parenchymal lung diseases (DPLD) in children represent a rare and heterogeneous group of chronic pulmonary disorders. Despite substantial advances in genetics and pathomechanisms, these often lethal diseases are still under-diagnosed. This is due to the fact that (i) the incidence is low, and (ii) clinical presentation, (iii) disease classification and (iv) specific treatment options are largely unknown. Methods: Here we systematically assessed the incidence, the presentation, the diagnostic yield and treatments of pediatric DPLD in Germany, using the Surveillance Unit for Rare Paediatric Disorders (ESPED). Results: The incidence of DPLD was 1.32 new cases per 1 million of children per year. The majority of these children were diagnosed within the first year of life. Overall survival was 87%. Using centralized data entry and stratification tools, the patients were categorized into an advanced classification system based on diagnostic algorithms, including clinical presentations, genetics and/or histology. Combining molecular and clinical information, this survey provides an etiological overview and specific diagnostic recommendations for children with DPLD. Conclusions: Standardized surveys and systematic classifications are valuable tools for the clinical handling of children with DPLD and aim to improve the disease understanding and the prognosis of these rare detrimental lung diseases.

Medizin - Open Access LMU - Teil 16/22
A prospective, non-randomized phase II trial of Trastuzumab and Capecitabine in patients with HER2 expressing metastasized pancreatic cancer

Medizin - Open Access LMU - Teil 16/22

Play Episode Listen Later Jan 1, 2009


Background: Pancreatic cancer is the fourth most common cause of cancer related death in Western countries. Advantages in surgical techniques, radiation and chemotherapy had almost no impact on the long term survival of affected patients. Therefore, the need for better treatment strategies is urgent. HER2, a receptor tyrosine kinase of the EGFR family, involved in signal transduction pathways leading to cell growth and differentiation is overexpressed in a number of cancers, including breast and pancreatic cancer. While in breast cancer HER2 has already been successfully used as a treatment target, there are only limited data evaluating the effects of inhibiting HER2 tyrosine kinases in patients with pancreatic cancer. Methods: Here we report the design of a prospective, non-randomized multi-centered Phase II clinical study evaluating the effects of the Fluoropyrimidine-carbamate Capecitabine (Xeloda (R)) and the monoclonal anti-HER2 antibody Trastuzumab (Herceptin (R)) in patients with non-resectable, HER2 overexpressing pancreatic cancer. Patients eligible for the study will receive Trastuzumab infusions on day 1, 8 and 15 concomitant to the oral intake of Capecitabine from day 1 to day 14 of each three week cylce. Cycles will be repeated until tumor progression. A total of 37 patients will be enrolled with an interim analysis after 23 patients. Discussion: Primary end point of the study is to determine the progression free survival after 12 weeks of bimodal treatment with the chemotherapeutic agent Capecitabine and the anti-HER2 antibody Trastuzumab. Secondary end points include patient's survival, toxicity analysis, quality of life, the correlation of HER2 overexpression and clinical response to Trastuzumab treatment and, finally, the correlation of CA19-9 plasma levels and progression free intervals.

Medizin - Open Access LMU - Teil 16/22
N-ethyl-N-nitrosourea mutagenesis produced a small number of mice with altered plasma electrolyte levels

Medizin - Open Access LMU - Teil 16/22

Play Episode Listen Later Jan 1, 2009


Background: Clinical chemical blood analysis including plasma electrolytes is routinely carried out for the diagnosis of various organ diseases. Phenotype-driven N-ethyl-N-nitrosourea (ENU) mouse mutagenesis projects used plasma electrolytes as parameters for the generation of novel animal models for human diseases. Methods: Here, we retrospectively evaluated the use of the plasma electrolytes calcium, chloride, inorganic phosphorus, potassium and sodium in the Munich ENU mouse mutagenesis project where clinical chemical blood analysis was carried out on more than 20,000 G1 and G3 offspring of chemically mutagenized inbred C3H mice to detect dominant and recessive mutations leading to deviations in various plasma parameter levels. Results: We identified a small number of animals consistently exhibiting altered plasma electrolyte values. Transmission of the phenotypic deviations to the subsequent generations led to the successful establishment of mutant lines for the parameters calcium and potassium. Published data from other phenotype-driven ENU projects also included only a small number of mutant lines which were generated according to altered plasma electrolyte levels. Conclusion: Thus, use of plasma electrolytes detected few mouse mutants in ENU projects compared to other clinical chemical blood parameters.

Medizin - Open Access LMU - Teil 15/22
Prodrug converting enzyme gene delivery by L-monocytogenes

Medizin - Open Access LMU - Teil 15/22

Play Episode Listen Later Jan 1, 2008


Background: Listeria monocytogenes is a highly versatile bacterial carrier system for introducing protein, DNA and RNA into mammalian cells. The delivery of tumor antigens with the help of this carrier into tumor-bearing animals has been successfully carried out previously and it was recently reported that L. monocytogenes is able to colonize and replicate within solid tumors after local or even systemic injection. Methods: Here we report on the delivery of two prodrug converting enzymes, purinedeoxynucleoside phosphorylase (PNP) and a fusion protein consisting of yeast cytosine deaminase and uracil phosphoribosyl transferase (FCU1) into cancer cells in culture by L. monocytogenes. Transfer of the prodrug converting enzymes was achieved by bacterium mediated transfer of eukaryotic expression plasmids or by secretion of the proteins directly into the host cell cytosol by the infecting bacteria. Results: The results indicate that conversion of appropriate prodrugs to toxic drugs in the cancer cells occured after both procedures although L. monocytogenes-mediated bactofection proved to be more efficient than enzyme secretion 4T1, B16 and COS-1 tumor cells. Exchanging the constitutively PCMV-promoter with the melanoma specific P4xTETP-promoter resulted in melanoma cell-specific expression of the prodrug converting enzymes but reduced the efficiencies. Conclusion: These experiments open the way for bacterium mediated tumor specific activation of prodrugs in live animals with tumors.