Molecular Basis Of Disease Pathogenesis Research Articles

Recent Updates in the Prevention of Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) are the leading causes of hepatic fibrosis and liver-related mortality worldwide, despite efficient hepatitis B and C antiviral therapies that have dramatically lowered the disease load. Although significant efforts have been exerted to understand the molecular basis of disease pathogenesis, there are currently few therapeutic alternatives available for NAFLD-associated fibrosis. Thus, NAFLD prevention is critical before the development of disease-related complications. In this context, there is a tremendous substantial global burden on public health systems to actively search for effective preventive and therapeutic targets for NAFLD. In this review, we highlight the current strategies to prevent progression and poor outcomes of NAFLD and to avoid complications associated with disease fibrosis, notably cirrhosis, portal hypertension, and liver cancer. We discuss different nonpharmacological measures, such as lifestyle modifications (weight loss, exercise, healthy diet) and other pharmacological interventions that could prevent NAFLD.

SCANCell reveals diverse inter-cluster interaction patterns in systemic lupus erythematosus across the disease spectrum.

High-dimensional mass cytometry (CyTOF), which provides both cellular signatures and inter-cluster interactions like the antagonism between immune activation and suppression, and the pro-inflammatory synergy, sheds light on the cellular and molecular basis of disease pathogenesis. However, revealing the aberrance of inter-cluster communication networks in CyTOF datasets remains a significant challenge. Here, we developed Sample Classification and direct Association Network among Cell clusters (SCANCell) that quantifies the direct association (DA) network of cell clusters. SCANCell was applied to profile inter-cluster interaction patterns of a well-recruited systemic lupus erythematosus (SLE) cohort, including 8 healthy controls, 10 active SLE patients (APs) and 8 remission SLE patients (RPs). SCANCell identified decreased inter-cluster interactions of CD8+ T cells in APs compared with RPs, and enhanced DA of CD8+ T cells after stimulation with immunostimulatory cytokine interleukin-2 in vitro. These discoveries prove that SCANCell can uncover pathology- and drug stimulation-associated inter-cluster interactions, which potentially benefits understanding of pathogenesis and novel therapeutic strategies. The main processing scripts of SCNACell are available at https://github.com/Lxc417/SCANCell. Other codes for the following data statistics are available from the corresponding author upon request. Supplementary data are available at Bioinformatics online.

Critical care of the pediatric patient with rheumatic disease

Extensive systemic illness and treatment with immunosuppressive agents often require patients with rheumatic diseases to be monitored or managed in the pediatric intensive care unit. Additionally, severe disease-specific manifestations of childhood rheumatic disorders present pediatric rheumatologists and critical care physicians with diagnostic and treatment challenges. Although mortality from rheumatic disease in children is rare, the most severe diseases, such as pediatric systemic lupus erythematosus and juvenile dermatomyositis, remain life-threatening. Advances in therapy have reduced the incidence of severe complications of autoimmune and inflammatory diseases and have expanded treatment options. However, patients with active underlying rheumatic disease and secondary infection who are being treated with immunosuppressive agents are most at risk for poor outcomes. Here we discuss the complications of childhood rheumatic conditions that necessitate critical intervention. We discuss how improved understanding of the cellular and molecular basis of disease pathogenesis holds the promise of more targeted therapy without the adverse effects of global immunosuppression.

MicroRNAs: novel therapeutic targets in neurodegenerative diseases

The prevalence of neurodegenerative disorders is rising steadily as human life expectancy increases. However, limited knowledge of the molecular basis of disease pathogenesis is a major hurdle in the identification of drug targets and development of therapeutic strategies for these largely incurable disorders. Recently, differential expression of endogenous regulatory small RNAs, known as 'microRNAs' (miRNAs), in patients of Alzheimer's disease, Parkinson's disease and models of ataxia suggest that they might have key regulatory roles in neurodegeneration. miRNAs that can target known mediators of neurodegeneration offer potential therapeutic targets. Our bioinformatic analysis suggests novel miRNA-target interactions that could potentially influence neurodegeneration. The recent development of molecules that alter miRNA expression promises valuable tools that will enhance the therapeutic potential of miRNAs.

Potential of genetic translational research in gastroenterology

The concept that genetic variation underlies inter-individual differences in drug response and contributes to the risk of developing common, complex disorders is expanding rapidly. Consequently the interest in genetic translational research has increased. Polymorphic DNA markers, either microsatellites or single nucleotide polymorphisms (SNPs), are used to assess genetic identities and track genetic differences between individuals. Given their abundance and stability, SNPs hold great promise as markers for mapping disease susceptibility loci for common, complex disorders by association studies. For this purpose the development of inexpensive, accurate, high-throughput methods for scoring large numbers of SNPs from hundreds of patients and controls is critical. Furthermore, gene expression profiling using DNA microarrays is likely to become a useful diagnostic tool enabling classification of disease phenotype based on molecular basis of disease pathogenesis, revealing information that cannot be obtained by histological assessment. Moreover, identification of differentially expressed genes in affected versus control tissue or over time in affected tissue will lead to better understanding of the mechanisms underlying disease and ultimately to the development of more effective drug therapies. To illustrate the potential of genetic translational research, several examples in the field of gastroenterology are described.

Transcriptional analysis of the response of poultry species to respiratory pathogens

Respiratory tract diseases are the single most important cause of economic loss due to infections among poultry populations worldwide. However, the molecular mechanisms of the host response to infections remain unknown. Here, we review the literature and describe the adoption of a conceptually simple approach to understand the genetic and biochemical responses of host cells during infection with respiratory pathogens, such as avian pneumovirus (APV). The strategy that we have adopted integrates the powerful techniques of cDNA subtraction hybridization and microarray analysis for global transcriptional profiling. The results of our investigations identify the specific transcriptional alterations in host-cell gene expression that result from an attempt by the host to combat and limit the spread of the pathogen or by the pathogen to enhance its own survival and ability to reproduce. Our studies suggest that a molecular description of host-pathogen interactions in terms of differential gene expression will provide key insights on the molecular basis of disease pathogenesis, pathogen virulence, and host immunity. In addition, the results suggest that the identification of genes and pathways with a role in host response to infection has considerable practical implications for the future design and development of effective immunomodulators and vaccines.

Susceptibility gene discovery for common metabolic and endocrine traits.

Almost all major causes of ill-health and premature death in human societies worldwide - including cancer, cardiovascular disease, diabetes and many infectious diseases - are, at least in part, genetically determined. Typically, risk of succumbing to one of these illnesses is thought to depend on both the individual repertoire of variation within a number of key susceptibility genes and the history of exposure to relevant environmental factors. For many of these conditions, the molecular basis of disease pathogenesis remains obscure. This represents a major obstacle to development of improved, rational strategies for disease treatment, prevention and eradication. It is easy therefore to appreciate the importance attached to efforts to deliver more comprehensive understanding of the molecular basis of disease pathogenesis. Nor is it hard to understand that identification of major susceptibility genes should highlight those components of molecular machinery that are critical for the preservation of normal health. The benefits promised are great, but progress to gene identification in multifactorial traits has been rather disappointing to date. Why is this? This review aims to answer this question by describing current and future approaches to gene discovery in multifactorial traits. The examples quoted will mostly relate to type 2 diabetes, but the issues and approaches are generic, and apply equally to other multifactorial traits in the endocrine and metabolic arena - type 1 diabetes; obesity; hyperlipidaemia; autoimmune thyroid disease; polycystic ovarian syndrome - and beyond.

Towards non-invasive imaging of HSV-1 vector-mediated gene expression by positron emission tomography

The overall goals of the broad and growing field of molecular medicine is to identify fundamental errors of disease and to develop corrections of them on the molecular level. At the same time, real-time imaging of gene expression in vivo aims towards a detailed analysis of both endogenous and exogenous gene expression in animal models of disease and in the clinical setting. Non-invasive imaging of endogenous gene expression may reveal insight into the molecular basis of disease pathogenesis and the extent of treatment response. When exogenous genes are introduced, e.g. by herpes simplex virus type 1 (HSV-1)-based vectors, to ameliorate a genetic defect or to add an additional gene function to cells, imaging techniques may reveal the assessment of the location, magnitude and duration of therapeutic gene expression and its correlation to the therapeutic effect. Here, we review the main approaches of non-invasive imaging techniques of gene expression in vivo with special reference to HSV-1 vector-mediated gene expression.

Impact of the genome project on the identification of disease genes

Cognitive defects and neurological diseases represent a major issue for human health, especially in aging populations. An estimated 15% of people >65 years are affected by mild-to-severe conditions of genetic origin affecting the central nervous system. Etiological factors of common neurological and psychiatric disorders remain elusive, apart from a few genes associated with rare disorders, such as one form of Alzheimer's disease(APP),a form of amyotrophic lateral sclerosis (SOD1), expanded polyglutamine track in Huntington's disease, and several types of ataxia or ion channel-associated conditions. With the human DNA sequence unveiled as a huge book of 3 gigabases,1,2how can we exploit the genome readout to identify disease-associated alleles and what is the projected impact for clinical genetics? The “book of life” is complete to >90% of euchromatic gene-rich regions, opening unprecedented possibilities for the characterization of all genes. The emerging human catalogue is thought to contain about 30 000 genes. Until now, factors underlying inherited conditions were mostly identified by positional cloning without prior knowledge of their biochemical function, and the catalogue unlocks the door to fast in silico searching(Figure 1, Parti I). Figure 1. The human genome catalogue unlocks the door to fast in silico searching and the design of novel high-throughput genotyping strategie. Complex molecular processes govern organogenesis and fitness builds upon the correct orchestration of gene actions throughout life. Most clinical phenotypes result from alterations of genetic instructions perturbing this tightly regulated system, while being strongly influenced by individual genetic makeup. The profound transition seen with the sequence information is the ability to foster novel concepts in our way of addressing biology as a global entity. Comprehensive studies of genome landscape and common polymorphisms will help identify causal and susceptibility factors at a much greater pace(Figure 1, Parts II and III). Although 60% of human genes have no characterized function yet, the sequence provides a body of information for the design of global strategies in functional genomics, for instance, using molecular evolution to underpin function by inference. Comparative genomics is one of the most powerful approaches to deciphering the molecular basis of disease pathogenesis(Figure 2). Figure 2. Genome sequences boost the power of model organisms and comparative genomics for identifying disease genes and understanding their function. Another essential approach to extracting biological meaning from the genetic message is illustrated by global transcriptome analysis(Figure 3).Grasping how global gene expression is processed into phenotype will be essential to any progress in molecular medicine. Hunting for disease-associated alleles by surveying dynamic biological systems at all relevant developmental stages and in all relevant tissues brings novel perspectives that will allow the correlation of molecular phenotype with clinical phenotype. Figure 3. Global analysis of the transcriptome by complex hybridization on assays: identifying and spotting all of the ≈ 16 000 to 20 000 genes that could be expressed in the human brain.

Analysis of Gene Transcription In Situ: Methodological Considerations and Application

Abstract The analysis of gene transcription in situ requires the localization of specific mRNA species in cell or tissue preparations. The main technique used to date is in situ hybridization (ISH) employing labeled nucleic acid probes complementary to the specific mRNA of interest. Advances in recombinant DNA technology and probe labeling methods, including the introduction of non-isotopic labels, have made the technique increasingly accessible. Further refinements in the methodology have enabled the detection of mRNA sequences in a variety of fixed cell and tissue preparations, including processed tissues, both at light and electron microscopy levels. When ISH is combined with immunohistochemistry, valuable insights into the molecular basis of disease pathogenesis in vivo can be gained.This review concentrates on the methodological considerations for ISH and its applications in pathology. Probe labeling, sample preparation, hybridization, and detection procedures are discussed. Alternative methods of in...