1,263 research outputs found

    Comparison of RNA extraction kits and histological stains for laser capture microdissected prostate tissue

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    Background Laser capture microdissection offers unique possibilities for the isolation of specific cell populations or histological structures. However, isolation of RNA from microdissected tissue is challenging due to degradation and minimal yield of RNA during laser capture microdissection (LCM). Our aim was to optimize the isolation of high-quality RNA from laser capture microdissected fresh frozen prostate tissue on the level of staining and RNA extraction. Results Cresyl violet and haematoxylin were compared as histological stains for LCM. While RNA quality was similar for cresyl violet (median RIN 7.4) and haematoxylin (median RIN 7.6), tissue morphology was more detailed with cresyl violet as compared to haematoxylin. RNA quality from the following kits was compared: RNeasy® Micro (median RIN 7.2), miRNeasy Mini (median RIN 6.6), Picopure® (median RIN 6.0), mirVana™ miRNA (median RIN 6.5) and RNAqueous®-Micro (median RIN 6.3). RNA quality from microdissected samples with either the RNeasy Micro or miRNeasy Mini kit, was comparable to RNA isolated directly from whole tissue slices (median RIN 7.5, p = 0.09). Isolated RNA from benign and prostate cancer microdissected tissue demonstrated that RNA quality can vary between regions from the same clinical sample. Additionally, RNA quality (r = 0.89), but not quantity (r = 0.69) could be precisely measured with the Agilent Bioanalyzer. Conclusions We demonstrate that staining with cresyl violet results in the isolation of high quality RNA from laser capture microdissected tissue with high discriminative morphology. The RNeasy Micro and miRNeasy Mini RNA extraction kits generated the highest quality RNA compared to Picopure, mirVana and RNAqueous with minimal loss of RNA quality during LCM

    Parkinson's Disease: Clinical Signs and Symptoms, Neural Mechanisms, Positron Emission Tomography, and Therapeutic Interventions

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    Parkinson's disease is one of the most frequent neurodegenerative brain diseases. Its time course is slow and is characterized by progressive loss of dopaminergic and other brainstem neurons resulting in malfunctioning of the cerebral neuronal systems responsible for motor functions. The clinical signs are slowness of movement, muscle rigidity and rest-tremor amongst other features. The cause of the disease is unknown, but recently involvement of genetic factors is being researched. Positron emission tomography (PET) allows in vivo determination of striatai dopaminergic activity. This has increased our insight in the pathophysiology of the disease and permits direct study of disease progression at a biochemical level and equally to monitor whether potential neuroprotective interventions are indeed effective. Thus far no drug has emerged but promising substances are currently being studied

    FDG- PET Imaging in Neurodegenerative Brain Diseases

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    Reward Processing in the Brain: A Prerequisite for Movement Preparation?

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    In the last decade, expanding animal studies on the cerebral organization of reward processing toward human in vivo situations has become possible. In this review, we define some of the concepts associated with reward, summarize the crucial importance of the dopaminergic system, and discuss the currently available neuroimaging studies in man. We will show that abstract concepts of human behavior like emotions, drive, arousal, and reinforcement are now open for further exploration in man at the level of neuronal circuit organization. The cerebral dopaminergic neurotransmitter circuitry does play an important role in the organization of both the motor and motivational system

    Circuit imaging biomarkers in preclinical and prodromal Parkinson's disease

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    Abstract Parkinson’s disease (PD) commences several years before the onset of motor features. Pathophysiological understanding of the pre-clinical or early prodromal stages of PD are essential for the development of new therapeutic strategies. Two categories of patients are ideal to study the early disease stages. Idiopathic rapid eye movement sleep behavior disorder (iRBD) represents a well-known prodromal stage of PD in which pathology is presumed to have reached the lower brainstem. The majority of patients with iRBD will develop manifest PD within years to decades. Another category encompasses non-manifest mutation carriers, i.e. subjects without symptoms, but with a known mutation or genetic variant which gives an increased risk of developing PD. The speed of progression from preclinical or prodromal to full clinical stages varies among patients and cannot be reliably predicted on the individual level. Clinical trials will require inclusion of patients with a predictable conversion within a limited time window. Biomarkers are necessary that can confirm pre-motor PD status and can provide information regarding lead time and speed of progression. Neuroimaging changes occur early in the disease process and may provide such a biomarker. Studies have focused on radiotracer imaging of the dopaminergic nigrostriatal system, which can be assessed with dopamine transporter (DAT) single photon emission computed tomography (SPECT). Loss of DAT binding represents an effect of irreversible structural damage to the nigrostriatal system. This marker can be used to monitor disease progression and identify individuals at specific risk for phenoconversion. However, it is known that changes in neuronal activity precede structural changes. Functional neuro-imaging techniques, such as 18F-2-fluoro-2-deoxy-D-glucose Positron Emission Tomography (18F-FDG PET) and functional magnetic resonance imaging (fMRI), can be used to model the effects of disease on brain networks when combined with advanced analytical methods. Because these changes occur early in the disease process, functional imaging studies are of particular interest in prodromal PD diagnosis. In addition, fMRI and 18F-FDG PET may be able to predict a specific future phenotype in prodromal cohorts, which is not possible with DAT SPECT. The goal of the current review is to discuss the network-level brain changes in pre-motor PD

    Treatment of Parkinson’s Disease:Early, Late, and Combined

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    Medical therapy in de novo Parkinson’s disease typically starts with a dopamine agonist or levodopa in combination with a decarboxylase inhibitor or if symptoms are still very mild with a MAO-B inhibitor. When patients do not (or no longer) respond satisfactorily to these initial therapies, different drugs can be initiated or combined (i.e., “add-on” treatments). These add-on therapies not only comprise oral agents but also intra-jejunal and intra-cutaneous treatments and functional neurosurgical procedures. This chapter starts with the treatment of de novo Parkinson’s disease whereafter indications and expected effects of the different “add-on” therapies will be described. The “add-on” therapies will be described in a hierarchical way and treatment algorithms will be provided based on prevailing symptoms including non-motor symptoms. The symptoms that will be discussed are: (1) bradykinesia and “wearing-OFF, " (2) tremor at rest, (3) dyskinesia, (4) gait and postural symptoms including freezing of gait, and (5) important non-motor symptoms. Finally, a comprehensive add-on treatment algorithm will be provided that takes into account non-motor symptoms that may limit the efficacy and tolerability of the different add-on therapies.</p

    Responsible access to credit for sole-traders and micro-organizations under unstable market conditions with psychometrics

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    In a context of market volatility, the growing complexity of financial products, and a shift towards self-employment, there is an increasing demand for inclusive financial services for sole traders and micro-organizations. To address this need, we conducted a study using real-time data from a Fintech lender in the Czech Republic to assess the effectiveness of a new financial literacy based psychometric credit scoring model (PSM) in improving access to finance for micro, small and medium sized enterprises (MSME) sector, particularly sole traders, and micro-organizations, during volatile market conditions. This study affirms that PSMs play a significant role in responsibly including this underserved sector. Specifically, we observed a 30% higher approval rate and a 23% lower default rate when utilizing the PSM versus the traditional credit scoring model (TCSM). Moreover, during the period of substantial market volatility and instability, such as the state-of-emergency during the COVID-19 pandemic, the PSM exhibited a 13% higher approval rate at a 20% lower default rate than the TCSM. This evidence supports the proposition that PSMs offer a viable option for promoting financial inclusion and targeted financial education among MSMEs in the face of instable financial markets

    Human phosphodiesterase 4D7 (PDE4D7) expression is increased in TMPRSS2-ERG positive primary prostate cancer and independently adds to a reduced risk of post-surgical disease progression

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    background: There is an acute need to uncover biomarkers that reflect the molecular pathologies, underpinning prostate cancer progression and poor patient outcome. We have previously demonstrated that in prostate cancer cell lines PDE4D7 is downregulated in advanced cases of the disease. To investigate further the prognostic power of PDE4D7 expression during prostate cancer progression and assess how downregulation of this PDE isoform may affect disease outcome, we have examined PDE4D7 expression in physiologically relevant primary human samples. methods: About 1405 patient samples across 8 publically available qPCR, Affymetrix Exon 1.0 ST arrays and RNA sequencing data sets were screened for PDE4D7 expression. The TMPRSS2-ERG gene rearrangement status of patient samples was determined by transformation of the exon array and RNA seq expression data to robust z-scores followed by the application of a threshold &gt;3 to define a positive TMPRSS2-ERG gene fusion event in a tumour sample. results: We demonstrate that PDE4D7 expression positively correlates with primary tumour development. We also show a positive association with the highly prostate cancer-specific gene rearrangement between TMPRSS2 and the ETS transcription factor family member ERG. In addition, we find that in primary TMPRSS2-ERG-positive tumours PDE4D7 expression is significantly positively correlated with low-grade disease and a reduced likelihood of progression after primary treatment. Conversely, PDE4D7 transcript levels become significantly decreased in castration resistant prostate cancer (CRPC). conclusions: We further characterise and add physiological relevance to PDE4D7 as a novel marker that is associated with the development and progression of prostate tumours. We propose that the assessment of PDE4D7 levels may provide a novel, independent predictor of post-surgical disease progression

    EpCAM expression in lymph node and bone metastases of prostate carcinoma: A pilot study

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    There is an urgent need for new imaging modalities in prostate carcinoma staging. A non-invasive modality that can assess lymph node and bone metastases simultaneously is preferred. Epithelial cell adhesion molecule (EpCAM) is a membranous protein of interest as an imaging target since it is overexpressed in prostatic carcinoma compared with benign prostate epithelium and compared with stroma. However, EpCAM expression in lymph node metastases is sparsely available in the literature and EpCAM expression in bone metastases is yet unknown. The current study evaluates the expression of EpCAM in prostate carcinoma lymph nodes, in matched normal lymph nodes, in prostate carcinoma bone metastases, and in normal bone by immunohistochemistry. EpCAM was expressed in 100% of lymph node metastases (21 out of 21), in 0% of normal lymph nodes (0 out of 21), in 95% of bone metastases (19 out of 20), and in 0% of normal bone (0 out of 14). Based on these results, EpCAM may be a feasible imaging target in prostate carcinoma lymph node and bone metastases. Prospective clinical trials are needed to confirm current results. Preoperative visualization of prostate carcinoma metastases will improve disease staging and will prevent unnecessary invasive surgery
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