Literature-based drug-drug similarity for drug repurposing: impact of Medical Subject Headings term refinement and hierarchical clustering.

Background: We describe herein, an improved procedure for drug repurposing based on refined Medical Subject Headings (MeSH) terms and hierarchical clustering method. Materials & methods: In the present study, we have employed MeSH data from MEDLINE (2019), 1669 US FDA approved drugs from Open FDA and a refined set of MeSH terms. Refinement of MeSH terms was performed to include terms related to mechanistic information of drugs and diseases. Results and Conclusions: In-depth analysis of the results obtained, demonstrated greater efficiency of the proposed approach, based on refined MeSH terms and hierarchical clustering, in terms of number of selected drug candidates for repurposing. Further, analysis of misclustering and size of noise clusters suggest that the proposed approach is reliable and can be employed in drug repurposing.

Modelling and optimal control of multi strain epidemics, with application to COVID-19.

Reinfection and multiple viral strains are among the latest challenges in the current COVID-19 pandemic. In contrast, epidemic models often consider a single strain and perennial immunity. To bridge this gap, we present a new epidemic model that simultaneously considers multiple viral strains and reinfection due to waning immunity. The model is general, applies to any viral disease and includes an optimal control formulation to seek a trade-off between the societal and economic costs of mitigation. We validate the model, with and without mitigation, in the light of the COVID-19 epidemic in England and in the state of Amazonas, Brazil. The model can derive optimal mitigation strategies for any number of viral strains, whilst also evaluating the effect of distinct mitigation costs on the infection levels. The results show that relaxations in the mitigation measures cause a rapid increase in the number of cases, and therefore demand more restrictive measures in the future.

Numerical modeling of mosquito population dynamics of Aedes aegypti.

BACKGROUND: The global incidences of dengue virus have increased the interest in studying and understanding the mosquito population dynamics. It is predominantly spread by Aedes aegypti in the tropical and sub-tropical countries in the world. Understanding these dynamics is important for public health in countries where climatic and environmental conditions are favorable for the propagation of these diseases. For this reason, a new model has been proposed to investigate the population dynamics of mosquitoes in a city. METHODS: The present paper discusses the numerical modeling of population dynamics of Ae. aegypti mosquitoes in an urban neighborhood of a city using the finite volume method. The model describes how populations spread through the city assisted by the wind. This model allows incorporating external factors (wind and chemical insecticides) and topography data (streets, building blocks, parks, forests and beach). The proposed model has been successfully tested in examples involving two Brazilian cities (City center, Juiz de Fora and Copacabana Beach, Rio de Janeiro). RESULTS: Invasion phenomena of Ae. aegypti mosquitoes have been observed in each of the simulations. It was observed that, inside the blocks, the growth of the population for both winged and aquatic phase causes an infestation of Ae. aegypti in a short time. Within the blocks the mosquito population was concentrated and diffused slowly. In the streets, there was a long-distance spread, which was influenced by wind and diffusion with a low concentration of mosquito population. The model was also tested taking into account chemical insecticides spread in two different configurations. It has been observed that the insecticides have a significant effect on the mosquito population for both winged and aquatic phases when the chemical insecticides spread more uniformly along all the streets in a neighborhood of a city. CONCLUSIONS: The presented methodology can be employed to evaluate and to understand the epidemic risks in a specific region of the city. Moreover the model allows an increase in efficiency of the existing mosquito population control techniques and to theoretically test new methods before involving the human population.

Lifestyle practices, health problems, and quality of life after coronary artery bypass grafting.

INTRODUCTION: Severe coronary artery disease continues to be a major health problem in India, and coronary artery bypass grafting (CABG) is the accepted modality of treatment. Post-operative long-term quality of life depends on the healthy lifestyle practices and appropriate control of risk factors. We tried to bring out the patient awareness and their practices after the surgery and their implications on their quality of life (QOL). MATERIALS AND METHODS: Five hundred patients who completed 6 months after isolated CABG were interrogated for their lifestyle practices, health problems, and quality of life using a structured questionnaire. Those who underwent additional cardiac procedures, redo CABG, and coronary interventions after CABG were excluded. RESULTS: Eighty percent were in good functional class (NYHA I, II). Detailed evaluation showed that only 11.6% adhered to healthy lifestyle practices. Obesity, uncontrolled diabetes mellitus, uncontrolled hypertension, and hypercholesterolemia continued to be problems in 9.6, 20.2, 35, and 48.4%, respectively. Quality of life was assessed to be good in 27.6%, average in 46.4%, and poor in 26%. Psychological evaluation showed that 23% were significantly anxious and 20% had significant depression. Pre-operative diagnosis and left ventricular function at discharge influenced the QOL. Unhealthy lifestyle practices and failure to attain risk factor reduction adversely affected the quality of life. CONCLUSION: This study emphasises the need for aggressive counselling as well as continuing health education to improve patient awareness about adopting healthy lifestyle practices after CABG to improve the quality of life.

Prevalence and Patterns of Learning Disabilities in School Children.

OBJECTIVE: To assess the prevalence and patterns of learning disabilities (LD) in school going children in a northern city of India. METHODS: The present cross-sectional study comprised of three-staged screening procedure for assessing learning disabilities of 3rd and 4th grade students studying in government schools. The first stage comprised of the teacher identifying at-risk student. In the second stage, teachers assessed at-risk students using Specific Learning Disability-Screening Questionnaire (SLD-SQ). The third stage comprised of assessment of the screen positive students using Brigance Diagnostic Inventory (BDI) part of NIMHANS Index of Specific Learning Disabilities for identifying the cases of LD. RESULTS: A total of 1211 (33.6%) children out of the total screened (n = 3600) were identified as at-risk by the teachers at the first stage. Of them, 360 were found to screen positive on the second stage using SLD-SQ. The most common deficits were missing out words or sentences while reading, misplacing letters or words while reading or writing, and making frequent mistake in spelling while writing or reading. Of these, 108 children were confirmed to have learning disability on the third stage using BDI, which represented 3.08% of the total population. CONCLUSIONS: Learning disability is an important concern in young school aged children. Early identification of such students can help in early institution of intervention and suitable modifications in teaching techniques.

Perceptions of teachers about learning disorder in a northern city of India.

BACKGROUND: Teachers are perhaps the closest observers of child's academic performance and can be instrumental in detecting learning disorder (LD) early. OBJECTIVES: The present study aimed to assess the teachers' perceptions about LD. MATERIALS AND METHODS: This is a cross-sectional questionnaire-based study in the public schools located in the urban, rural and slum areas of Chandigarh. Teachers were recruited from 20 randomly selected schools out of a total of 103 schools in the Union Territory by proportionate sampling. The sample size required for α of 0.05 and power of 0.80 to detect a difference of 15% from base rate of 35% was 80. Eighty teachers of 3(rd) and 4(th) grades of these schools were recruited using purposive sampling. Teachers were briefed for 5 minutes about the symptoms of LD. They were asked questions using a structured questionnaire about their socio-demographic status, methods of teaching, and students' progress and their perception about LD. Descriptive statistics was mainly used to represent nominal and ordinal data using frequency and percentages. Non-parametric statistical tests were used to assess relationship between the variables. RESULTS: Eighty teachers were recruited, 87.5% were females, 57.5% had more than 5 years teaching experience; 56.3% of teachers thought that they were aware of LD, 67.5% of teachers perceived that they do encounter children with LD in the school, 43.8% endorsed educating such children in special schools, while 36.3% endorsed integration to regular schools. Interestingly, more than three fifth of teachers were willing to undergo special training for LD intervention. CONCLUSION: Teachers acknowledge that there is a need for further steps to be taken to help children with LD. They perceive opening special cells or sending such children to special schools for appropriate intervention which may not tally with the perception of clinician who may wish to provide LD intervention in hospital setting.