REVIEW Download: 69| View: 691| Comments: 0 | doi:10.20944/preprints201901.0170.v1
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: gut microbiota; macrophages; TLR mimicry; immunoepigenetics; metabolism; sterile inflammation
Online: 17 January 2019 (03:05:26 CET)
Perturbation in the microbial population/colony index has harmful consequences on human health. Both biological and social factors influence the composition of the gut microbiota and promote gastric diseases. Changes in the gut microbiota manifest in disease progression owing to epigenetic modification in host which influences differentiation and function of immune cells adversely. Uncontrolled use of antibiotics; chemotherapeutic drugs and change in the diet pattern usually contribute to the changes in the colony index of sensitive strains known to release microbial content in the tissue micromillieu. Ligands released from dying microbes induce TLR mimicry on interaction with TLR abnormally which skew hypoxia and sterile inflammation contributing to severity of disease like IBD autoimmunity and cancer. Various modalities/interventions practiced across the globe and future strategies for microbiota based therapeutic approaches with special emphasis on tumor and inflammatory diseases are reviewed here. Therefore the major aim and scope of this manuscript is to both discuss various modalities/interventions across the globe and to design future microbiota based therapeutic approaches for mitigating the burden with special emphasis on tumor and Inflammatory diseases.
Fri, 28 December 2018
REVIEW Download: 62| View: 203| Comments: 0 | doi:10.20944/preprints201812.0333.v1
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: gap junction; connexin; angiogenesis; cell mechanics; cell migration; cellular stiffness
Online: 28 December 2018 (05:19:52 CET)
Angiogenesis, the sprout and growth of new blood vessels from existing vasculature, is an important process of tumor development for the supply of oxygen and nutrition to cancer cells. Endothelial cell is a critical player in angiogenic process by modulating cell proliferation, cell motility, and cell morphology in the response to pro-angiogenic factors and environments provided by tumor and cancer cells. Recent in vivo and in vitro studies have revealed that gap junction of endothelial cells also participates in the promotion of angiogenesis. Pro-angiogenic factors modulate gap junction function and connexins expression in endothelial cells, whereas endothelial connexins involve in angiogenic tube formation and cell migration of endothelial cells via both gap junction channel function dependent or independent mechanisms. In particular, connexin might have the potential to regulate cell mechanics such as cell morphology, cell migration, and cellular stiffness that are dynamically changed during angiogenic processes. Here, we review the implication for endothelial gap junction and cellular mechanics in vascular angiogenesis.
Wed, 5 December 2018
REVIEW Download: 83| View: 189| Comments: 0 | doi:10.20944/preprints201812.0066.v1
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: renal cell carcinoma; circulating DNA; CTC; diagnosis; follow-up; genetic alteration; target therapy
Online: 5 December 2018 (08:01:30 CET)
Liquid biopsy, based on the circulating tumor cells (CTCs) and cell-free nucleic acids has potential applications at multiple points throughout the natural course of cancer, from diagnosis to follow-up. The advantages of doing ctDNA assessment vs. tissue-based genomic profile are the minimal procedural risk, the possibility to serial testing in order to monitor disease-relapse and response to therapy over time and to reduce hospitalization costs during the entire process. However some critical issues related to ctDNA assays should be taken in consideration. The sensitivity of ctDNA assays depends on the assessment technique and genetic platforms used, on tumor-organ, stage, tumor heterogeneity, tumor clonality. The specificity is usually very high, whereas the concordance with tumor-based biopsy is generally low. In patients with renal cell carcinoma (RCC) qualitative analyses of ctDNA have been performed with interesting results regarding selective pressure from therapy, therapeutic resistance, exceptional treatment response to everolimus and mutations associated with aggressive behavior. Quantitative analyses showed variations of cfDNA levels at different tumor stage. Compared to CTC assay, ctDNA is more stable than cells and easier to isolate. Splice variants, information at single-cell level and functional assays along with proteomics, transcriptomics and metabolomics studies can be performed only in CTCs.
Mon, 3 December 2018
ARTICLE Download: 73| View: 108| Comments: 0 | doi:10.20944/preprints201812.0017.v1
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: primary brain tumor; HER2; immunohistochemistry
Online: 3 December 2018 (09:24:06 CET)
Background and objectives: Primary brain tumors include any tumors arising in the brain whose prognosis is poor due to their histologic characteristics. The aim of this research was to evaluate the frequency of HER2 tumor marker in primary malignant brain tumors. Materials and Methods: This descriptive study was conducted on the samples admitted to the pathology laboratory with diagnosis of primary brain tumor during 2008–2015. Results: From among 107 patients (61.7% males and the rest females) with mean age of 40.4 years, the highest frequency of tumor location was in supratentorial region of the brain (including lobes and ventricles) (63.85% cases). High-grade astrocytoma had the highest prevalence at diagnosis (43.9%), followed by low-grade astrocytoma (37.4%). As for HER2 score, 42.1% of patients were HER2-positive (scores 2 & 3). On the other hand, 5.6% of patients were HER2-negative (-), 40.2% were positive (+), and 54.2% were positive (++). The patients with high-grade astrocytoma had older age (P < 0.001), higher HER2 positivity (P = 0.024) and percentage (P < 0.001) compared to the patients with low-grade astrocytoma. Conclusions: HER2 expression is dependent on the type of brain tumors. High expression of HER2 in high-grade astrocytoma may be useful for therapeutic purposes. The future research is needed to confirm these results with a large number of patients in different areas.
Fri, 16 November 2018
ARTICLE Download: 191| View: 786| Comments: 0 | doi:10.20944/preprints201811.0395.v1
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: nanopore sequencing; droplet digital PCR; Capnocytophaga canimorsus; diagnosis; sepsis
Online: 16 November 2018 (09:45:38 CET)
We present a case of Capnocytophaga canimorsus septic shock after a dog bite in an immunocompetent individual, where real-time nanopore metagenomic sequencing characterized the microbial agent within 19 hours, with subsequent confirmation using droplet digital PCR. Oral swabs from the dog demonstrated a nearly-identical C. canimorsus isolate by sequencing.
Tue, 13 November 2018
ARTICLE Download: 74| View: 141| Comments: 0 | doi:10.20944/preprints201811.0310.v1
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: tessellation; forensic picture; bullets; homology; proximity
Online: 13 November 2018 (10:41:14 CET)
Here we show how a recently-introduced method from algebraic topology, namely proximal planar vortex 1-cycles, might be helpful in detecting hidden features of the shapes and holes in images, therefore contributing to the solution of both cold and fresh forensic cases. In particular, we test the efficacy of this technique by assessing one of the most puzzling cases of recent history, i.e., Aldo Moro’s death. Terrorists of the Red Brigades claimed that they killed Moro when he was placed inside the trunk of a car,shooting him with a barrage of bullets. We demonstrate, based on the analysis of the photographs taken during the autoptic procedure, that the terrorist’s account does not hold true. Our results, showing different series of shots, point towards a three-step execution, with the first phasestaking place outside the car. In conclusion, the novel forensic analysis method introduced in this paper permits the evaluation of a collection of vortex cycles/nerves equipped with a connectedness proximity, which makes it possible to assess unexpected spatial clusters in photographs.
Mon, 22 October 2018
CASE REPORT Download: 61| View: 63| Comments: 0 | doi:10.20944/preprints201810.0491.v1
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: cytomegalovirus (CMV); infection, reactivation, epidemiology, host-virus interaction, CMV-specific IgG; protective IgG level, avidity, adoptive/acquired immune response, hematopoietic stem cell transplantation (HSCT); secondary immunodeficiency, Quantiferon, pentamer, β2-microglobulin/beta 2-Microglobulin
Online: 22 October 2018 (11:53:47 CEST)
Although the existing paradigm states that CMV reactivation is under control of cellular immune response, the role of humoral counterpart is underestimated. Anti-CMV positive woman after conditioning with Bu-Flu-ATG underwent stem cell transplantation from fully matched, seronegative sibling donor. In immunodeficient recipient fast and significant decrease of specific immune response was observed but reconstitution of marrow-derived B and NK cells was prior thymic origin T cells. The lowest CMV-IgG(89 U/ml) was observed just before CMV viremia. Noteworthy, the sole and exclusive factor of CMV-specific immune response is a residual recipient antibody class IgG. The CMV-quantiferon increase was observed later, but in the first phase immune reconstitution of the PHA-induced IFNγ release was significantly lower than that CMV-induced. It corresponds with NK cells increase at the top of lymphocyte reconstitution and undetected CMV-specific CD8 cells by pentamer technique. Most of NK cells are CD16+, thus are stimulated by residual IgG. In immunocompetent donor the cellular and humoral immune response increases in parallel manner but symptoms of CMV mononucleosis were observed till the increase of specific IgG. Our observations shed light on a unique host-CMV interaction: indicate that significant decrease of CMV-IgG is a good predictor for CMV reactivation during secondary immunodeficiency.
Wed, 10 October 2018
ARTICLE Download: 86| View: 187| Comments: 0 | doi:10.20944/preprints201810.0211.v1
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: lipoprotein; extracellular vesicles; exosome; ectosome; stress response; resistant cancer; metastatic cancer; heat shock stress
Online: 10 October 2018 (09:44:17 CEST)
Resistant cancer often shows a particular secretory trait such as heat shock proteins (HSPs) and extracellular vesicles (EVs), including exosomes and oncosomes surrounded by lipid bilayers. Lipoproteins are biochemical assemblies that transport hydrophobic lipid (a.k.a. fat) molecules in body fluid and are composed of a single-layer phospholipid and cholesterol outer shell, lipids molecules within the particles, and apolipoproteins embedded in the membrane. However, lipoprotein storage and secretion by cancer cells have not well-investigated yet. We found lipoproteins were stored and abundantly secreted by neuroendocrine, castration-resistant prostate cancer (NEPC / CRPC) cells but barely secreted by colon cancer cells and oral squamous cell carcinoma (OSCC) cells. In addition, large EVs (approx. 300 nm diameter) and potential oncosomes were released by CRPC and OSCC cells. Proteomics revealed that CRPC cells secreted EVs enriched with tetraspanins and extracellular matrices which were reduced upon heat shock stress and alternatively lipoproteins and HSPs were secreted upon stress. Heat shock stress triggered secretion of lipoprotein-EV complexes that contained apolipoprotein A, B, C and E. These data suggested that vesicular assembly composed of EVs and lipoproteins enriched with cholesterols and phospholipids may be stored in resistant cancer cells but released upon cell stress that is increased in cancer therapies.
Thu, 27 September 2018
REVIEW Download: 141| View: 130| Comments: 0 | doi:10.20944/preprints201809.0533.v1
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: mycoplasma; virulence effectors; pathogenesis
Online: 27 September 2018 (05:54:04 CEST)
Members of the genus Mycoplasma and related organisms impose a substantial burden of infectious diseases on humans and animals, but the last comprehensive review of mycoplasmal pathogenicity was published 20 years ago. Post-genomic analyses have now begun to support the discovery and detailed molecular biological characterization of a number of specific mycoplasmal virulence factors. This review covers three categories of defined mycoplasmal virulence effectors: 1) specific macromolecules including the superantigen MAM, the ADP-ribosylating CARDS toxin, sialidase, cytotoxic nucleases, cell-activating diacylated lipopeptides, and phosphocholine-containing glycoglycerolipids; 2) the small molecule effectors hydrogen peroxide, hydrogen sulfide, and ammonia; and 3) several putative mycoplasmal orthologs of virulence effectors documented in other bacteria. Understanding such effectors and their mechanisms of action at the molecular level connects the biology of the bacteria to direct effects on the host and host responses they elicit, and is expected to translate into new interventions for human and veterinary mycoplasmosis.
Wed, 12 September 2018
ARTICLE Download: 121| View: 133| Comments: 0 | doi:10.20944/preprints201809.0222.v1
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: psoriasis, arthritis, inflammation, granulocytes, redox signaling, oxidative stress, lipid peroxidation, 4-hydroxynonenal, lipids, endocannabinoid system
Online: 12 September 2018 (13:43:16 CEST)
Inflammatory granulocytes are characterized by oxidative burst, which may promote oxidative stress and lipid modification both in affected tissues and on systemic level. On the other hand, redox signaling involving lipid peroxidation products acting as second messengers of free radicals play important, not yet fully understood, roles in pathophysiology of inflammation and various stress-associated disorders. Therefore, the aim of this study was to evaluate the onset of oxidative stress and alterations of enzyme-dependent lipid metabolism resulting from redox imbalance in granulocytes and plasma obtained from patients with psoriasis vulgaris or psoriatic arthritis, in comparison to the healthy subjects. The results obtained revealed enhanced activity of pro-oxidant enzymes NADPH and xanthine oxidases in granulocytes, with a decrease of enzymatic and non-enzymatic antioxidants in plasma of psoriatic patients. The Nrf2 and its regulators were increased in both forms of psoriasis, while HO-1 levels were increased only in psoriasis vulgaris. Redox imbalance was associated with decreased levels of phospholipids and of free PUFAs, but with enhanced activity of enzymes involved in lipid metabolism (PLA2, PAF-AH COX1/2) and increased lipid peroxidation products 4-hydroxynonenal (4-HNE), isoprostanes and neuroprostanes. Increased endocannabinoids and GPR55 were observed in both forms of the disease, while expression of CB1 was increased only in pateints with psoriatic arthritis, opposite to CB2, which was increased only in psoriasis vulgaris. Protein modifications by ROS and lipid peroxidation product 4-HNE promoted apoptosis of granulocytes by increased caspases in both forms of psoriasis. This study indicates that excessive activation of granulocytes, causing oxidative stress and lipid modifications, is an important pathophysiology of psoriasis. Consequently, lower Nrf2 activity and CB2 expression may promote progression of psoriasis into advanced, arthritic form of the disease.
Wed, 8 August 2018
REVIEW Download: 301| View: 274| Comments: 0 | doi:10.20944/preprints201808.0155.v1
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: amyloid diseases; biocomputing; drug design; natural antiamyloids
Online: 8 August 2018 (04:27:10 CEST)
Amyloids result from the aggregation of several unrelated proteins, due to either specific mutations or promoting intra- or extra-cellular conditions. Structurally, they are rich in intermolecular β-sheets and are the causative agents of several diseases, both neurodegenerative and systemic. It is believed that the most toxic species are small aggregates, referred to as oligomers, rather than the final fibrillar assemblies. Their mechanisms of toxicity are mostly mediated by aberrant interactions with the cell membranes, with resulting derangement of membrane-related functions. Much effort is being put in the search for natural antiamyloid agents, and/or in the development of synthetic molecules. Actually, it is well documented that the prevention of amyloid aggregation results in several cytoprotective effects. Here, we portray the state of the art in the field. Several natural compounds are effective antiamyloid agents, notably tetracyclines and polyphenols. They are generally non-specific, as documented by their partially overlapping mechanisms, and the capability to interfere with the aggregation of several unrelated proteins. Among rationally designed molecules, we mention the prominent examples of β-breakers peptides, whole antibodies and fragments thereof, and the special case of drugs contrasting transthyretin aggregation. In this framework, we stress the pivotal role of the computational approaches. When combined with biophysical methods, in several cases they have helped clarify in detail the protein/drug modes of interaction, which make it plausible that more effective drugs will be developed in the future.
Wed, 25 July 2018
REVIEW Download: 176| View: 156| Comments: 0 | doi:10.20944/preprints201807.0478.v1
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: pheochromocytoma; paraganglioma; GAPP; metastasis; prognosis; catecholamine; gene mutation; immunohistochemistry; pathology; diagnosis
Online: 25 July 2018 (11:41:52 CEST)
Pheochromocytoma and sympathetic paraganglioma (PPGL) are rare neuroendocrine tumors characterized by catecholamine production in the adrenal medulla and extra-adrenal paraganglia. PPGL with metastasis was termed malignant PPGL. However, the distinction between “benign” and “malignant” PPGLs has been debated. Currently, all PPGLs are believed to have some metastatic potential and are assigned malignant tumors (ICD-O/3) by the WHO Classification of Endocrine Organs (2017, 4th edition). Therefore, the previous categories benign and malignant PPGL have been eliminated in favor of a risk stratification approach. The Grading of Adrenal Pheochromocytoma and Paraganglioma (GAPP) is a tool for risk stratification for predicting metastasis and the prognosis of patients. At least 30% of PPGLs are hereditary, with 20 genes identified and genotype-phenotype correlations clarified. Of these, VHL, RET, and NF1 have been well investigated and are the primary cause of bilateral PCC. In addition, succinate dehydrogenase gene subunits SDHB and SDHD are strongly correlated with extra-adrenal location, younger age, multiple tumors, metastasis, and poor prognosis. Disease stratification by catecholamine phenotype and molecular profiling correlates with histological grading by GAPP. PPGLs should be understood comprehensively based on clinical, biochemical, molecular, and pathological data for patient care. A flow chart for pathological diagnosis is included.
Fri, 25 May 2018
ARTICLE Download: 221| View: 273| Comments: 0 | doi:10.20944/preprints201805.0359.v1
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: autism spectrum disorder; endocrine; estrogen; immune activation; melanin concentrating hormone
Online: 25 May 2018 (10:37:23 CEST)
The voluminous daily output of autism research has become increasingly disconnected, existing largely within highly specific subspecialty areas, and lacking cross-disciplinary linkages of context, theory, and findings to inform a unified body of knowledge. Robust syntheses of published research across the fields of psychiatry, cellular and molecular biology, neurology, endocrinology, immunology, behavioral and social sciences, and pedagogy may help clarify and extend current knowledge by guiding more efficient future research efforts investigating underlying causes, developmental divergences, novel treatments, and specific, sensitive biological markers in autism. This synthesis of interdisciplinary research indicates the hypothalamic-pituitary-adrenal (HPA) stress axis may be at the center of an interaction among sex steroids, immune function, signaling protein transcriptions, neurogenesis, and dysregulation of brain structures sending or receiving projections from the HPA stress axis. These interaction manifest observably as a range of sexually dimorphic behaviors and functional limitations often falling within the current diagnostic features of Autism Spectrum Disorder (ASD). The pathogenicity of endocrine dysregulation may serve as a valuable model for developing a cohesive theory of ASD by explaining how the HPA and connected brain areas respond to extreme conditions of dysregulated endocrine signaling to cause symptoms associated with autism.
Wed, 11 April 2018
ARTICLE Download: 197| View: 240| Comments: 0 | doi:10.20944/preprints201804.0151.v1
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: Cervical cancer – viruses – Human Papillomaviruses – Epstein-Barr virus – Id-1
Online: 11 April 2018 (13:49:57 CEST)
Epstein–Barr virus (EBV) has been recently shown to be co-present with high-risk human papillomaviruses (HPVs) in human cervical cancer; thus, these oncoviruses play an important role in the initiation and/or progression of this cancer. Accordingly, our group has recently viewed the presence and genotyping distribution of high-risk HPVs in cervical cancer in Syrian women; our data pointed out that HPVs are present in 95.45% of our samples. Herein, we aim to explore the co-prevalence of EBV and high-risk HPVs in 44 cervical cancer tissues from Syrian women using polymerase chain reaction (PCR), immunohistochemistry (IHC) and tissue microarray (TMA) analyses. We found that EBV and high-risk HPVs are co-present in 15/44 (34%) of the samples. Additionally, we report that the co-expression of LMP1 and E6 genes of EBV and high-risk HPVs, respectively, is associated with poorly differentiated squamous cell carcinomas phenotype; this is accompanied by a strong and diffused Id-1 overexpression, which is an important regulator of cell invasion and metastasis. These data imply that EBV and HPVs are co-present in cervical cancer in the Middle East area including Syria and their co-presence is associated with a more aggressive cancer phenotype. Future investigations are needed to elucidate the exact role of EBV and HPVs cooperation in cervical carcinogenesis.
Thu, 8 March 2018
ARTICLE Download: 1510| View: 6987| Comments: 3 | doi:10.20944/preprints201803.0062.v1
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: Lyme disease; Borrelia burgdorferi; Tickborne disease; Chronic infection; Spirochete culture
Online: 8 March 2018 (07:08:02 CET)
Introduction: Lyme disease is a tickborne illness that generates controversy among medical providers and researchers. One of the key topics of debate is the existence of persistent infection with the Lyme spirochete, Borrelia burgdorferi, in patients who have been treated with recommended doses of antibiotics yet remain symptomatic. Persistent spirochetal infection despite antibiotic therapy has recently been demonstrated in non-human primates. We present evidence of persistent Borrelia infection despite antibiotic therapy in patients with ongoing Lyme disease symptoms. Materials & Methods: In this pilot study, culture of body fluids and tissues was performed in a randomly selected group of 12 patients with persistent Lyme disease symptoms who had been treated or who were being treated with antibiotics. Cultures were also performed on a group of 10 control subjects without Lyme disease. The cultures were subjected to corroborative microscopic, histopathological and molecular testing for Borrelia organisms in four independent laboratories in a blinded manner. Results: Motile spirochetes identified histopathologically as Borrelia were detected in culture specimens, and these spirochetes were genetically identified as Borrelia burgdorferi by three distinct polymerase chain reaction (PCR) methods. Spirochetes identified as Borrelia burgdorferi were cultured from the blood of seven subjects, from the genital secretions of ten subjects, and from a skin lesion of one subject. Cultures from control subjects without Lyme disease were negative for Borrelia using these methods. Conclusions: Using multiple corroborative detection methods, we showed that patients with persistent Lyme disease symptoms may have ongoing spirochetal infection despite antibiotic treatment, similar to findings in non-human primates. The optimal treatment for persistent Borrelia infection remains to be determined.
Wed, 3 January 2018
ARTICLE Download: 695| View: 360| Comments: 0 | doi:10.20944/preprints201801.0021.v1
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: oxidative stress; in vitro fertilization (IVF); infertile women; follicular fluid (FF); granulosa cells
Online: 3 January 2018 (06:37:39 CET)
Oxidative stress negatively affects folliculogenesis and embryo development. However, a reliable and biologically accurate indicator of oxidative stress does not yet exist. On these bases, the aim of this study was to assess -and compare- blood and follicular fluid (FF) redox status in 45 infertile subjects (and 45 age-matched controls) undergoing in vitro fertilization (IVF) and to establish its connection with the outcome of IVF. Blood and FF were obtained at the time of egg retrieval and immediately analyzed. Firstly, ROS production in blood leukocytes and in granulosa cells was assessed. Oxidative stress markers in blood and in granulosa cells resulted significantly (p<0.001) increased in infertile patients compared to controls. Then, a redox index was obtained in plasma and in FF of patients and controls. The main findings emerging from our study in infertile women are: i) blood oxidative stress reflects FF oxidative stress as demonstrated by the significant correlation between blood redox markers and FF redox markers; ii) a significant correlation between oxidative stress parameters and the considered IVF outcomes is present. We suggest the strict monitoring of the redox parameters for the improvement of assisted reproductive techniques success rate and infertility management.
Wed, 23 August 2017
ARTICLE Download: 490| View: 457| Comments: 0 | doi:10.20944/preprints201708.0080.v1
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: multiple sclerosis; neuroinflammation; astrocytes; myelin; bioinformatics
Online: 23 August 2017 (17:46:28 CEST)
We previously reported that in multiple sclerosis (MS) patients with a progressive form of the disease, spinal cord periplaques extend distance away from plaque borders and are characterized by the co-occurrence of partial demyelination, astrocytosis and low-grade inflammation. However, transcriptomic analyses comparing periplaques to adjacent normal-appearing white matter (NAWM) areas did not allow providing a comprehensive view of molecular events in astrocytes vs oligodendrocytes. Here, we re-assessed our transcriptomic data with the aim of identifying functionally-relevant co-expression networks that would reflect astrocyte vs oligodendrocyte molecular signatures in periplaques. We identified an astrocytosis-related gene module comprising GFAP, the hub gene CX43/GJA1 and a set of transcripts forming a TGFB/SMAD1/SMAD2 genomic signature. Partial demyelination was characterized by a co-expression network which, besides myelin genes, comprised a highly significant number of translation/elongation-related genes. Interestingly, the main oligodendrocyte-related hub we identified was NDRG1, a gene previously shown to be specifically silenced in the NAWM of MS patients. This result indicated that NDRG1 down-regulation could be an important event in the process of periplaque partial demyelination. To establish a putative link between NDRG1 down-regulation and a cytokine/chemokine signature, we then sought to identify cytokine/chemokine genes whose mRNA levels inversely correlated with those of NDRG1. Following this approach we found 5 candidate immune-related genes whose up-regulation associated with NDRG1 down-regulation: TGFB1, PDGFC, IL-17D, IL-33, and IL-12A. From these results we propose that in the spinal cord of MS patients with progressive forms of the disease, TGFB1 may limit acute inflammation but concurrently induce astrocytosis and an alteration of oligodendrocytes terminal differentiation.
Tue, 13 June 2017
REVIEW Download: 485| View: 511| Comments: 0 | doi:10.20944/preprints201706.0059.v1
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: mitochondrial; muscle biopsy; ragged red; COX-negative; subsarcolemmal; immunohistochemistry
Online: 13 June 2017 (06:23:36 CEST)
Mitochondria are dynamic organelles ubiquitously present in nucleated eukaryotic cells, subserving multiple metabolic functions, including cellular ATP generation by oxidative phosphorylation (OXPHOS). The OXPHOS machinery comprises five transmembrane respiratory chain enzyme complexes (RC). Defective OXPHOS gives rise to mitochondrial diseases (mtD). The incredible phenotypic and genetic diversity of mtD can be attributed at least in part to the RC dual genetic control (nuclear DNA [nDNA] and mitochondrial DNA [mtDNA]) and the complex interaction between the two genomes. Despite the increasing use of next-generation-sequencing (NGS) and various -omics platforms in unraveling novel mtD genes and pathomechanisms, current clinical practice for investigating mtD essentially involves a multipronged approach including clinical assessment, metabolic screening, imaging, pathological, biochemical and functional testing to guide molecular genetic analysis. This review addresses the broad muscle pathology landscape including genotype-phenotype correlations in adult and paediatric mtD, the role of immunodiagnostics in understanding some of the pathomechanisms underpinning the canonical features of mtD, and recent diagnostic advances in the field.
Mon, 8 May 2017
REVIEW Download: 533| View: 530| Comments: 0 | doi:10.20944/preprints201705.0071.v1
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: Toxoplasma gondii; neurophysiology; host-parasite interaction, neuroimmune, testosterone, dopamine, catecholamine, glutamatergic
Online: 8 May 2017 (18:34:39 CEST)
Although the parasite Toxoplasma gondii is one of the most pervasive neurotropic pathogens in the world, the host-parasite interactions during CNS infection and consequences of neurological infection are just beginning to be unraveled. The chronic stages of infection have been considered dormant, although several studies have found correlations of infection with an array of host behavioral changes. These may facilitate parasite transmission and impact neurological diseases. During infection, in addition to the presence of the parasites within neurons, host-mediated neuroimmune and hormonal responses to infection are also present. T. gondii induces numerous changes to host neurons during infection and globally alters host neurological signaling pathways, as discussed in this review. Understanding the neurophysiological changes in the host brain is imperative to understanding the parasitic mechanisms and to delineate the effects of this single-celled parasite on health and its contribution to neurological disease.
Tue, 18 April 2017
ARTICLE Download: 653| View: 830| Comments: 0 | doi:10.20944/preprints201704.0102.v1
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: aging; age-related disease; mortality rate; positive feedback loop; vicious cycle
Online: 18 April 2017 (02:45:04 CEST)
Age-related diseases (ARDs) are the leading cause of death worldwide, and contribute to 90% of mortality in developed countries. Interestingly, the mortality rates of individual ARDs increase exponentially with age. Processes described by the exponential growth function typically involve a branching chain reaction or, more generally, a positive feedback loop. Here I propose that each ARD is mediated by one or several positive feedback loops (vicious cycles). I then identify critical vicious cycles in five major ARDs: atherosclerosis, hypertension, diabetes, Alzheimer’s and Parkinson’s. I also propose that the progression of ARDs can be halted by selectively interrupting the vicious cycles and suggest the most promising targets. An evolutionary perspective is also offered.
Thu, 13 April 2017
ARTICLE Download: 451| View: 546| Comments: 0 | doi:10.20944/preprints201704.0078.v1
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: Ochratoxin A, insulin, glucagon, glucose, rat plasma, pathology, immunohistochemistry
Online: 13 April 2017 (11:46:19 CEST)
In this study, diabetogenic effects of long term Ochratoxin A (OTA) administration in rats were investigated and its role in the etiology of diabetes mellitus (DM) was examined utilizing 42 female Wistar rats for these purposes. The rats were divided into 3 different study and control groups according to the duration of the OTA administration. Rats received 45 μg OTA daily in their feed for 6, 9 and 24 weeks study groups. Three control groups without any treatment were also used in the same periods. Blood and pancreatic tissue samples were collected during the necropsy at the end of 6, 9 and 24 weeks. Plasma values of insulin, glucagon and glucose in study and control groups were determined. Pancreatic lesions were evaluated by histopathological examination; then insulin and glucagon expression in these lesions were determined by immunohistochemical methods. Statistically significant decrease in insulin levels in contrast to increases in glucagon and glucose levels in blood were observed. Slight degeneration in Langerhans islet cells were observed at the histopathological examination in all OTA treated groups. Immunohistochemistry of pancreatic tissue revealed decreased insulin and increased glucagon expression. This study demonstrated that OTA may cause pancreatic damage in Langerhans islet and predispose rats to DM.
Thu, 16 March 2017
REVIEW Download: 859| View: 778| Comments: 0 | doi:10.20944/preprints201703.0125.v1
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: Extracellular vesicles (EVs); Peptidylarginine deiminases (PADs); Chlor-amidine (Cl-Am); cancer; neurodegeneration; deimination; cytoskeleton; induced pluripotent stem cells (iPSCs); histone H3; epigenetics
Online: 16 March 2017 (17:54:15 CET)
Extracellular vesicle (EV) release, which occurs in most eukaryotic cells, has recently been associated with peptidylarginine deiminase (PAD)-driven protein deimination. Evidence points to the involvement of deiminated cytoskeletal proteins and changes in histone deimination. Both PADs and EVs are associated with various pathologies including cancers, autoimmune and neurodegenerative diseases. The elevated PAD expression observed in cancers may contribute to increase in EV shedding observed from cancer cells, contributing to cancer progression. Similarly, elevated PAD expression observed in neurodegenerative diseases may cause increased EV shedding and spread of neurodegenerative EV cargo, contributing to disease progression and pathologies. Pharmacological inhibition of PAD-mediated deimination using pan-PAD inhibitor Cl-amidine, reduced cellular EV release in prostate cancer cells, rendering them significantly more susceptible to chemotherapeutic drugs. Studies on models of central nervous system damage have demonstrated critical functional roles for PADs and neuroprotective effects using PAD inhibitors in vivo, while human neurodegenerative iPSC in vitro models showed evidence of increased protein deimination. Besides using refined PAD inhibitors to selectively manipulate EV biogenesis for novel combination therapies in cancer treatment, we also speculate how EV biogenesis could be targeted via the newly identified PAD-pathway to ameliorate neurodegenerative disease progression.