Mechanism of action and recruitment of antigen-presenting cells in a mouse model of multiple sclerosis

La sclérose en plaques (SEP) est largement acceptée comme étant une maladie auto-immune du système nerveux central (SNC) dirigée par les cellules T auto-réactives. Cette maladie est très répandue au Canada. L'encéphalomyélite auto-immune expérimentale (EAE) est le modèle animal le plus utilisé pour l’étude de la SEP. Malgré l’importance des cellules T dans cette pathologie, il est important de souligner que ce sont les cellules présentatrices d'antigènes (CPA) myéloïdes, et surtout les cellules dendritiques (CD), qui amorcent l’activation des cellules T auto-réactives dans les organes lymphoïdes secondaires ainsi que leur éventuelle réactivation dans le compartiment du SNC plus tard au cours de la maladie. Cependant, il existe une disparité dans l'identification des différentes sous-populations de CPA myéloïdes en raison de l'absence de marqueurs fiables et spécifiques, ce qui constitue une entrave dans le domaine de l'immunothérapie cellulaire. Par ailleurs, les mécanismes moléculaires responsables de la régulation du recrutement des CPA myéloïdes au niveau de la vasculature cérébrale suite à l'activation de l'endothélium du SNC sont encore mal connus. L'interleukine-6 (IL-6) est une cytokine pro-inflammatoire essentielle à la différenciation des lymphocytes TH17 auto-réactifs. Ces derniers sont des régulateurs clés de l'EAE et jouent un rôle important dans la SEP. Ainsi, le premier objectif de ma thèse était de démontrer que l'IL-6 joue un second rôle dans l'EAE en stimulant l'endothélium du SNC à exprimer les molécules nécessaires au recrutement des CPA myéloïdes. Nous démontrons que : (1) les cellules endothéliales du SNC expriment le récepteur de l’IL-6 (IL-6R) ; (2) l’ablation génétique de l’IL-6R spécifiquement dans l'endothélium atténue le recrutement des neutrophiles, des macrophages et des CDs, et prévient le développement de l'EAE ; et (3) l'IL-6 stimule les cellules endothéliales à produire CXCL1 et PTGS2, des protéines impliquées dans le recrutement et l'activation des cellules myéloïdes. Le deuxième objectif général de mon étude était d'obtenir une vue d'ensemble phénotypique et fonctionnelle des sous-populations de CD présentes pendant la phase initiale d'induction de l'EAE. À cette fin, nous avons utilisé la technologie de séquençage de l'ARN unicellulaire (scRNAseq) pour comparer la signature transcriptionnelle des cellules CD11c+ issues des nœuds lymphatiques au cours de la phase préclinique de l'EAE. Nous montrons que : (1) quatre grandes sous-populations de CD sont présentes, soit les CD115+ monocytaires (mDC), les SiglecH+ plasmacytoïdes (pDC), les XCR1+ conventionnelles de type 1 (cDC1) et les CCR7+ conventionnelles de type 2 (cDC2) ; (2) les cDC2, une sous-population spécifique de CPA, présentent des niveaux transcriptonnels élevés de cytokines pro-inflammatoires (IL-6, IL-12) et de marqueurs de maturation et de co-stimulation pour la présentation des antigènes (CD80, CD83, CD86, OX40L) ; (3) miR155, un microARN connu pour son rôle dans l'EAE, est principalement exprimé dans les cDC2 ; et (4) que l'enzyme D-aminoacide oxydase (Dao), qui produit du peroxyde d'hydrogène (H2O2) à partir d’acides aminés D, est régulée à la hausse dans les cDC2 des souris miR155-/- . En résumé, mon travail de thèse met l'accent sur le rôle critique des CPA myéloïdes lors des premiers événements précliniques de l'EAE et il suggère un nouveau rôle important de la signalisation classique de l'IL-6 dans le développement de l'EAE et le recrutement des leucocytes. Finalement, il identifie en outre des cibles et des biomarqueurs potentiels à des fins diagnostiques et thérapeutiques.Multiple sclerosis (MS) is widely accepted as an autoreactive T cells driven autoimmune disorder of the central nervous system (CNS), highly prevalent in Canada. Experimental autoimmune encephalomyelitis (EAE) is the established animal model for studying MS. Antigen-presenting cells (APCs) of myeloid origin, most importantly, dendritic cells initiate the priming of autoreactive T cells in the secondary lymphoid organs, and their eventual reactivation in the CNS compartment later in the disease course. However, a disparity exists in identifying myeloid APCs subsets with accuracy due to absence of reliable and specific markers, causing a hindrance in the field of cellbased immunotherapy. In addition, more needs to be deciphered on the molecular mechanisms that regulate activation of CNS endothelium for recruitment of myeloid APCs. Interleukin-6 (IL-6) is a pro-inflammatory cytokine, essential for differentiation of self-reactive TH17 lymphocytes, which are key regulators of EAE and play an important role in MS. The first objective of my thesis was to demonstrate that IL-6 plays another role in EAE by stimulating the CNS endothelium to express molecules required for the recruitment of myeloid antigen-presenting cells. We show that: (1) endothelial cells in the CNS express IL-6 receptor (IL-6R); (2) genetic deletion of IL-6R specifically in the endothelium blocks neutrophils, macrophages and dendritic cells recruitment as well as EAE development; (3) ICAM1-expressing extravascular myeloid APCs are reduced in number during the pre-onset stage of EAE; and (4) IL-6 stimulates endothelial cells to produce CXCL1 and PTGS2, which are involved in recruitment and activation of myeloid cells. The second general objective of my study was to get a phenotypic and functional overview of DC subsets present during the initial induction phase of EAE. For that purpose, we used the single-cell RNA sequencing (scRNAseq) technology to compare the transcriptional signature of CD11c+ cells from lymph nodes during the pre-clinical phase of EAE. We show that: (1) four major subsets of DCs are present: CD115+ monocytic DC (mDC), SiglecH+ plasmacytoid DC (pDC), XCR1+ conventional DCs type-1 (cDC1) and CCR7+ conventional DCs type-2 (cDC2); (2) cDC2 exhibit elevated expression of pro-inflammatory cytokines (IL-6, IL-12), maturation marker (CD83) and costimulatory molecules for antigen presentation (CD80, CD86, OX40L); (3) miR155, a microRNA known to have a role in EAE, is predominantly expressed in cDC2; (4) the enzyme D-amino acid oxidase (Dao), that produces hydrogen peroxide (H2O2) from D-amino acids, is upregulated in cDC2 of miR155-/- mice. In summary, my thesis work emphasizes on the critical role of myeloid APCs during initial pre-clinical events of EAE. Moreover, it suggests additional important role of classical IL-6 signaling in EAE development and leukocyte recruitment. It further identifies potential targets and biomarkers for diagnostics and therapeutic purposes

Reinforcement of the Bank Loan Model using the Feature Selection Method of Machine Learning

Does feature selection and machine learning (ML) guarantee the effectiveness of the bank credit system model? This article aims to analyze this problem. In fact, in finance, expert-based credit risk models still dominate. In this study, we establish a new benchmark using consumer data and present machine learning methods. A risk prediction that is as accurate as possible is an important requirements for credit scoring models. In addition, regulators expect that the models should to be auditable and transparent. As a result, the superior predictive power of contemporary machine learning algorithms cannot be fully utilized in credit scoring because very simple predictive models, such as several ML classifiers, are still widely used. As a result, significant potential is missed, increasing reserves or the number of credit defaults. A framework for comparing scores before and after feature selection machine learning models that are transparent, auditable, and explainable is presented in this article, as well as the various dimensions that need to be taken into consideration in order to make credit scoring models understandable. In accordance with this framework, we give an overview of the models which demonstrate how it can be used in credit scoring, and compare the results to scorecards' interpretability. The model presented demonstrates that machine learning techniques can maintain their ability to enhance predictive power while still maintaining a comparable level of interpretability

Maternal hemoglobin: socio-demographic and obstetric determinants in rural Central India

Background: Maternal Anemia is a global health problem with adverse implications on materno-fetal outcome. Various socio-demographic and obstetric factors affect prevalence of anemia.Methods: A hospital based, cross-sectional, observational study was carried out among pregnant women seeking antenatal care at Kasturba Hospital of MGIMS, Sewagram, a rural tertiary care institute in central India. Information was collected about demographic variables, age, gravidity, parity, literacy, area of residence and socioeconomic status. Hemoglobin levels in first trimester and pre delivery were measured by coulter and correlated with socio-demographic and obstetric factors.Results: Among 500 pregnant women of first trimester, 249 (49.8%) had anemia, 154 (30.8%) mild, 86 (17.2%) moderate and 9 (1.8%) severe anemia. More women with anemia were of lesser age, resided in rural area, belonged to middle and lower economic class, lived with joint families and had less than 12 years of formal education.Conclusions: Anemia is prevalent in pregnant women in this geographic region of central India. Age, higher gravidity, higher parity, rural residence, low socioeconomic status and less than 12 years of formal education, are risk factors. Appropriate age at marriage, small family norm, education of girl child, anemia prevention strategy in adolescent girls and financial empowerment of women are suggested strategies for prevention of anemia and improved maternofetal outcome

LFSR Next Bit Prediction through Deep Learning

Pseudorandom bit sequences are generated using deterministic algorithms to simulate truly random sequences. Many cryptographic algorithms use pseudorandom sequences, and the randomness of these sequences greatly impacts the robustness of these algo-rithms. Important crypto primitive Linear Feedback Shift Register (LFSR) and its combina-tions have long been used in stream ciphers for the generation of pseudorandom bit sequences. The sequences generated by LFSR can be predicted using the traditional Ber-lekamp Massey Algorithm, which solves LFSR in 2×n number of bits, where n is the de-gree of LFSR. Many different techniques based on ML classifiers have been successful at predicting the next bit of the sequences generated by LFSR. However, the main limitation in the existing approaches is that they require a large number (as compared to the de-gree of LFSR) of bits to solve the LFSR. In this paper, we have proposed a novel Pattern Duplication technique that exponentially reduces the input bits requirement for training the ML Model. This Pattern Duplication technique generates new samples from the available data using two properties of the XOR function used in LFSRs. We have used the Deep Neural Networks (DNN) as the next bit predictor of the sequences generated by LFSR along with the Pattern Duplication technique. Due to the Pattern Duplication tech-nique, we need a very small number of input patterns for DNN. Moreover, in some cases, the DNN model managed to predict LFSRs in less than 2n bits as compared to the Ber-lekamp Massey Algorithm. However, this technique was not successful in cases where LFSRs have primitive polynomials with a higher number of tap points

Biological synthesis and characterization of lead sulphide nanoparticles using bacterial isolates from heavy metal rich sites

ABSTRACT Lead is highly poisonous heavy metal (regardless if inhaled or swallowed), affecting almost every organ and system in the body. The main target for lead toxicity is the nervous system. Lead poisoning typically results from ingestion of food or water contaminated with lead; but may also occur after accidental ingestion of contaminated soil, dust, or lead-based paint. Bioremediation of lead by bacteria could be an effective measure to remove lead. This study involves the synthesis of lead sulphide nanoparticle using lead chloride and calcium sulphate salts utilizing bacterial strains isolated from the industrial sites of Allahabad and Kanpur. For synthesis, bacterial cell mass was centrifuged to separate supernatant from pellet. Both supernatant and cell pellet were challenged with lead chloride and calcium sulphate salts and lead sulphide nanoparticles were effectively synthesized. These extracellularly synthesized nanoparticles exhibited an absorbance maximum at 330 nm and were characterized using UV Visible spectrophotometer and Transmission Electron Microscope. The use of these strains seems to be promising and advantageous as it is serving dual purposes of (i) bioremediation and (ii) nanoparticle synthesis. These biologically synthesized nanoparticles could be used in various applications

Newborn birth weight: a trend towards positive paradigm shift in rural central India

Background: Birth weight is one of the important determinants of neonatal wellbeing. It has many determinants including maternal nutritional status and gestational age. Low birth weight is associated with high neonatal and childhood mortality and morbidity. Over the years the birth weight is showing the increasing trend in developing countries like India. The study aimed at finding out the changing pattern of birth weight over a decade in rural India.Methods: Retrospective data of 43,114 births was collected through hospital information system. Neonatal birth weight was analyzed over a period of 10 years from 2007-2016. Demographic data was studied to study the determinants.Results: Over the period of 10 years, proportion of newborn with low birth weight (below 2500 grams) declined from 56.35 % to 43.65 %. The rise in mean birth weight was 147 gram in male infant and 114 grams in female. There was overall reduction in proportion of very low birth weight and extremely low birth weight babies. A linear relationship was observed between improved birth weight, socio economic status, age at marriage and maternal weight gain during pregnancy.Conclusions: A positive trend towards improved newborn birth weight was observed in study site of rural central India. Better antenatal care, improved maternal nutrition and improved social status of women in the community are the determinants found to have a positive correlation

Correlation of serum homocysteine levels and pregnancy outcome: the dilemma continues

Background: Hyperhomocysteinemia has been implicated as a risk factor for complications in pregnancy including abortion, preeclampsia and placental abruption. The present study was designed to study the correlation, if any, of Hyperhomocysteinemia with pregnancy outcome.Methods: Pregnant women between 14 to 24 weeks of gestation were included as subjects. Serum homocysteine levels and MTHFR gene (Methylenetetrahydrofolate reductase 677C>T) polymorphism was estimated. The women were followed till delivery and obstetric & neonatal outcomes were noted.Results: A total of 81 women were followed till delivery. Out of these 42 women had an uncomplicated pregnancy and delivery and 39 women had at least one antenatal or perinatal complication. Difference between mean serum homocysteine in both the groups was not statistically significant (p=0.403).No significant difference was found in the occurrence of different genotypes in the 2 groups though women with TT genotype were found to have higher serum homocysteine levels as compared to other genotypes.Conclusions: Though the serum homocysteine levels were higher in the women with pregnancy complications as compared to women without complications but the difference was not statistically significant

Rapid Assessment of Avoidable Visual Impairment in Two Coastal Districts of Eastern India for Determining Effective Coverage: A Cross-Sectional Study

Purpose: To measure the prevalence and causes of visual impairment (VI) among the 40+ age population in two coastal districts of India and to determine the levels of effective cataract surgical coverage (eCSC) and effective refractive error coverage (eREC) in the study population. Methods: A cross-sectional study was done on 4200 people chosen using cluster sampling in two coastal districts of Odisha, an eastern state in India. A team consisting of trained optometrists and social workers conducted the ocular examination which included unaided, pinhole, and aided visual acuity assessments followed by examination of the anterior segment and lens. Results: Overall, 3745 (89.2%) participants were examined from 60 study clusters, 30 in each district. Among those examined, 1677 (44.8%) were men, 2554 (68.2%) were educated and number? (17.8%) used distance spectacles during the survey. The prevalence of VI adjusted for age and gender was 12.77% (95% CI 11.85–13.69%). Multiple logistic regression showed that older age (OR 3.1; 95% CI 2.0–4.7) and urban residence (OR 1.2; 95% CI 1.0–1.6) were associated with VI. Being educated (OR 0.4; 95% CI 0.3–0.6) and using glasses (OR 0.3; 95% CI 0.5–0.2) were found to provide protection; therefore, resulting in lower instances of VI. Cataract (62.7%) and uncorrected refractive errors (27.1%) were the two main causes of VI. The eCSC was 35.1%, the eREC for distance was 40.0%, and the eREC for near was 35.7%. Conclusion: VI remains a challenge in Odisha, as the prevalence is high and the surgical coverage is poor. Nearly 90% of VI is avoidable indicating that targeted interventions are required to address this problem

Coexistence of carcinoma cheek with tuberculosis: a rarity

Coexistence of tuberculosis and cheek malignancy is a rare phenomenon and it has never been reported to the best of our knowledge. Here, we present a case of carcinoma cheek with tuberculosis in a 50 year old male patient who was successfully managed by multimodality approach by combining anti-tubercular therapy with chemotherapy and radiotherapy

Japanese encephalitis virus induces human neural stem/progenitor cell death by elevating GRP78, PHB and hnRNPC through ER stress

Japanese encephalitis virus (JEV), which is a causative agent of sporadic encephalitis, harbours itself inside the neural stem/progenitor cells. It is a well-known fact that JEV infects neural stem/progenitor cells and decreases their proliferation capacity. With mass spectrometry-based quantitative proteomic study, it is possible to reveal the impact of virus on the stem cells at protein level. Our aim was to perceive the stem cell proteomic response upon viral challenge. We performed a two-dimensional gel electrophoresis-based proteomic study of the human neural stem cells (hNS1 cell line) post JEV infection and found that 13 proteins were differentially expressed. The altered proteome profile of hNS1 cell line revealed sustained endoplasmic reticulum stress, which deteriorated normal cellular activities leading to cell apoptosis. The proteomic changes found in hNS1 cell line were validated in vivo in the subventricular zone of JE infected BALB/c mice. Congruent alterations were also witnessed in multipotent neural precursor cells isolated from human foetus and in autopsy samples of human brain clinically diagnosed as cases of JE patients. Endoplasmic reticulum resident chaperone GRP78, mitochondrial protein Prohibitin and heterogeneous nuclear ribonucleoprotein hnRNPC (C1/C2) have been shown to interact with viral RNA. Hence it is proposed that these are the principle candidates governing endoplasmic reticulum stress-induced apoptosis in JEV infection