A universal hydro-mechanical coupled behavior model for clay-bearing strata-Molecular-level simulation approach.

Clay minerals in soils and rocks exhibit large volume change upon interaction with water and this behavior becomes even more complex when the strata are being stressed by the engineering and environmental loads. Therefore, a realistic prediction of the hydro-mechanical behavior of the clay-bearing strata is always a challenge due to their coupled swelling-mechanical response in the cases of geotechnical and geoenvironmental engineering problems, nuclear waste storage in clay-bearing rock repositories, shale gas extraction, and other uses of clay in the manufacturing industry. All the existing behavior models have restricted applications in the engineering and other fields of practice mainly due to the partial consideration of the structure and fabric of clay-bearing strata in the model formulation. In this study, a hydro-mechanical behavior model has been formulated using the parameters acquired from the molecular-level simulations and modeling of the volume change and stress-strain behavior of the clay-bearing structure. The Molecular Mechanics and Molecular Dynamic simulations were performed on the natural structure of the clay-bearing strata formulated using Monte Carlo technique. The mathematical model, developed from the simulation results, can predict the overall hydro-mechanical behavior of clay-bearing strata for all possible combinations of clay minerals, non-clay minerals, salts causing cementation of the soil/rock structure, confining pressures, and the induced strain levels. The developed model has successfully been validated through laboratory and field testing on the clay-bearing strata in both the elastic and elasto-plastic regions of the stress-strain behavior and also from the data of two (02) swelling clays (MX-80 and FEBEX Bentonite) from the existing literature, supporting the universal nature of the developed behavior model.

Screening of silent myocardial ischaemia using a stress test in rheumatoid arthritis patients: Association with traditional risk factors and disease activity.

INTRODUCTION: We aimed to screen the presence of silent myocardial ischaemia, in established rheumatoid arthritis (RA) patients, using a stress test then to evaluate its association with the disease activity and the cardiovascular (CV) risk factors and Heartscore. METHODS: It is a transversal study in a rheumatologic centre in Tunisia. One hundred three RA patients, asymptomatic for CV diseases, were submitted to a stress test. Demographic data, CV risk factors and disease characteristics were assessed and risk factors of silent myocardial ischaemia in RA patients were identified. RESULTS: There were 103 patients (sex-ratio = 0.3) with a mean age of 53 ± 10 years. The evaluation of the disease activity showed that the mean Disease Activity Score in 28 joints C-reactive protein, Clinical Disease Activity Index and Simplified Disease Activity Index were 3.9 ± 1.38, 17.17 ± 11.4 and 33.39 ± 26, respectively. The ischaemic ratio (CT/HDL) revealed that 42% of patients had a moderate to high myocardial ischaemic risk. HeartSCORE was high in 35% of cases. A silent myocardial ischaemia in the stress test was found in 11 patients (10.6%) and was associated with male sex (p = 0.03), advanced age (p = 0.04), erosive character (p = 0.05), the advanced age of the RA diagnosis (p = 0.01) and the ischaemic ratio (p = 0.05). No relationship was found with the majority of traditional CV risk factors nor with disease activity variables. CONCLUSION: Our results corroborated the hypothesis that the stress test could reveal subclinical CV dysfunction and supported the utility of the Heartscore as a screening tool.

Variation of homocysteine levels in rheumatoid arthritis patients: relationship to inflammation, cardiovascular risk factors, and methotrexate.

BACKGROUND: The aim of this study was to evaluate the variation of homocysteine (Hcy) levels in patients with rheumatoid arthritis (RA) and to analyze the relationship to inflammatory parameters, cardiovascular risk, and methotrexate (MTX). METHODS: This cross-sectional study assessed disease activity and treatment in RA patients. The European League Against Rheumatism (EULAR) 2015 HeartSCORE was performed for cardiovascular (CV) risk estimation and levels of plasma Hcy, serum folate concentrations, vitamin B12, and erythrocyte sedimentation rate (ESR) were measured. RESULTS: A total of 103 participants with mean age 53 ± 10 years and mean disease duration 10.55 ± 7.34 years were included. Patients were treated with MTX in 69.9% of cases and corticosteroid in 80.5% of cases. Of all patients, 13% had a cardiovascular inheritance, 25% were hypertensive, and 18% had diabetes. The EULAR 2015 HeartSCORE was high and very high (≥5%) in 35% of cases. Mean Hcy level was 12.54 ± 4.2 µmol/L [6.89-32.92] and hyperhomocysteinemia was noted in 20.4% of patients. Analytic study demonstrated that hyperhomocysteinemia was associated with male gender (p = 0.01), MTX use (p = 0.01), smoking (p = 0.008), renal failure (p = 0.04), and high disease activity (p = 0.05), but there was no association with the HeartSCORE (p = 0.23). Hcy level was negatively correlated with folate (p = 0.009) and vitamin B12 level (p = 0.02) and positively with age (p = 0.01), C­reactive protein (CRP; p = 0.05), and Simplified Disease Activity Index (SDAI; p = 0.03). In multivariate logistic regression analysis, current MTX use, levels of vitamin B12 and creatine, and Clinical Disease Activity Index (CDAI) appeared to be independent factors associated with hyperhomocysteinemia. CONCLUSION: MTX use, CDAI, and the levels of vitamin B12 and creatine are independent factors associated with hyperhomocysteinemia.

Design and Rationale of the National Tunisian Registry of Percutaneous Coronary Intervention: Protocol for a Prospective Multicenter Observational Study.

BACKGROUND: Coronary artery diseases remain the leading cause of death in the world. The management of this condition has improved remarkably in the recent years owing to the development of new technical tools and multicentric registries. OBJECTIVE: The aim of this study is to investigate the in-hospital and 1-year clinical outcomes of patients treated with percutaneous coronary intervention (PCI) in Tunisia. METHODS: We will conduct a prospective multicentric observational study with patients older than 18 years who underwent PCI between January 31, 2020 and June 30, 2020. The primary end point is the occurrence of a major adverse cardiovascular event, defined as cardiovascular death, myocardial infarction, cerebrovascular accident, or target vessel revascularization with either repeat PCI or coronary artery bypass grafting (CABG). The secondary end points are procedural success rate, stent thrombosis, and the rate of redo PCI/CABG for in-stent restenosis. RESULTS: In this study, the demographic profile and the general risk profile of Tunisian patients who underwent PCI and their end points will be analyzed. The complexity level of the procedures and the left main occlusion, bifurcation occlusion, and chronic total occlusion PCI will be analyzed, and immediate as well as long-term results will be determined. The National Tunisian Registry of PCI (NATURE-PCI) will be the first national multicentric registry of angioplasty in Africa. For this study, the institutional ethical committee approval was obtained (0223/2020). This trial consists of 97 cardiologists and 2498 patients who have undergone PCI with a 1-year follow-up period. Twenty-eight catheterization laboratories from both public (15 laboratories) and private (13 laboratories) sectors will enroll patients after receiving informed consent. Of the 2498 patients, 1897 (75.9%) are managed in the public sector and 601 (24.1%) are managed in the private sector. The COVID-19 pandemic started in Tunisia in March 2020; 719 patients (31.9%) were included before the COVID-19 pandemic and 1779 (60.1%) during the pandemic. The inclusion of patients has been finished, and we expect to publish the results by the end of 2022. CONCLUSIONS: This study would add data and provide a valuable opportunity for real-world clinical epidemiology and practice in the field of interventional cardiology in Tunisia with insights into the uptake of PCI in this limited-income region. TRIAL REGISTRATION: Clinicaltrials.gov NCT04219761; https://clinicaltrials.gov/ct2/show/NCT04219761. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR1-10.2196/24595.

Molecular autopsy and clinical family screening in a case of sudden cardiac death reveals ACTN2 mutation related to hypertrophic/dilated cardiomyopathy and a novel LZTR1 variant associated with Noonan syndrome.

BACKGROUND: Genetic cardiac diseases are the main trigger of sudden cardiac death (SCD) in young adults. Hypertrophic cardiomyopathy (HCM) is the most prevalent cardiomyopathy and accounts for 0.5 to 1% of SCD cases per year. METHODS: Herein, we report a family with a marked history of SCD focusing on one SCD young adult case and one pediatric case with HCM. RESULTS: For the deceased young adult, postmortem whole-exome sequencing (WES) revealed a missense variant in the ACTN2 gene: c.355G > A; p.(Ala119Thr) confirming the mixed hypertrophic/dilated cardiomyopathy phenotype detected in the autopsy. For the pediatric case, WES allowed us the identification of a novel frameshift variant in the LZTR1 gene: c.1745delT; p.(Val582Glyfs*10) which confirms a clinical suspicion of HCM related to Noonan syndrome. CONCLUSION: The present study adds further evidence on the pathogenicity of ACTN2: p. Ala119Thr variant in SCD and expands the mutational spectrum of the LZTR1 gene related to Noonan syndrome.

[Left ventricular hypertrophy in hemodialysis patient: Prevalence, electrocardiographic, echocardiographic study and associated risk factors]. / Hypertrophie ventriculaire gauche chez les hémodialysés : prévalence, étude électrique, échographique et facteurs de risque.

BACKGROUND: Left ventricular hypertrophy is the most prevalent cardiac abnormality in hemodialysis patients. The diagnosis of this abnormality is possible by electrocardiogram and/or echocardiography. Our study aimed to assess the prevalence of left ventricular hypertrophy in hemodialysis patients and the accuracy of different electrocardiographic criteria. METHODS: This was a cross-sectional retrospective study including 60 hemodialysis patients between 2017 and 2018. A left ventricular mass index higher than 115g/m2 and 95g/m2 respectively in men and women defines echocardiographic left ventricular hypertrophy. We assessed left ventricular hypertrophy prevalence, sensitivity, specificity, and area under the receiver-operating characteristics (ROC) curve of fourteen different electrocardiographic criteria for identification of left ventricular hypertrophy. RESULTS: This was a cohort of 60 patients composed of 27 men and 33 women with a mean age 52.6±15,8years. Hypertension was the most common cardiovascular risk factor (82 %). The prevalence of left ventricular hypertrophy at echography was 65 %. Prevalence of left ventricular hypertrophy at electrocardiographic varied across the different criteria ranging from 5 % (R wave in DI) to 32 % (Perugia score). The highest left ventricular hypertrophy prevalence at electrocardiographic was found with the five following criteria: Perugia score (32 %), Peguero-Lo Presti index (28 %), Sokolow-Lyon index, Cornell index, Framingham-adjusted Cornell voltage (17 %). Sensitivity was ranged from 5 % (R in DI, Gubner-Ungerleider index, and product) to 41 % (Perugia score). The specificity of most criteria was ≥90 % except for the Perugia score (85 %). The sensitivity, specificity, postitive and negative productive values and left ventricular hypertrophy prevalence using the five most accurate criteria combined were respectively 48, 90, 70.28, 77.85 and 33 %. Hypertension, duration of HD, arteriovenous fistula, interdialytic weight gain, systolic blood pressure, hemoglobin <9g/dL and hyperparathyroidism were significantly associated with left ventricular hypertrophy. CONCLUSION: The prevalence of left ventricular hypertrophy detected by echocardiography was high. All electrocardiographic criteria had a low sensibility and a high specificity in the diagnostic of echocardiographic left ventricular hypertrophy. To improve the accuracy of electrocardiographic criteria, it is necessary to combine several electrocardiographic criteria and not often focused on a single classic electrocardiographic index.

Impact of Ramadan fasting on lipid profile and cardiovascular risk factors in patients with stable coronary artery disease.

BACKGROUND: The effects of Ramadan fasting (RF) on cardiometabolic risk factors in patients with stable ischemic heart disease are not well known. AIM: The aim of this study was to evaluate the impact of RF on lipid profile and cardiovascular risk factors in patients with a stable coronary heart disease. METHODS: A prospective observational study carried out in the Cardiology department of Charles Nicolle Hospital (Tunisia). Eighty-four patients with a stable ischemic heart disease who intended to fast were enrolled during May 2020. Detailed clinical and biochemical assessments were performed before and after the holy month. Parameters of glycemic control, lipid profile, ultrasensitive C-reactive protein concentration (us-CRP) and homocysteine were performed before- and after- Ramadan (BR and AR, respectively). RESULTS: Eighty-four patients including 79 males and 5 females, with a mean age of 57±7 years completed the study. Levels of cholesterol, triglycerides, low-density lipoprotein-cholesterol and apoprotein A were significantly improved AR fasting in comparison with their BR values. There was a significant decrease in blood fasting glucose, insulin level, Homeostasis model assessment of insulin resistance index and in us-CRP level. CONCLUSION: In patients with stable ischemic heart disease, RF may be accompanied by an improvement of lipid profile and glycemic parameters without increase in coronary events.

Association study of six candidate genes with major depressive disorder in the North-Western population of Pakistan.

People around the world are currently affected by Major Depressive Disorder (MDD). Despite its many aspects, symptoms, manifestations and impacts, efforts have been made to identify the root causes of the disorder. In particular, genetic studies have concentrated on identifying candidate genes for MDD and exploring associations between these genes and some specific group of individuals. The aim of this research was to find out the association between single nucleotide polymorphisms in 6 candidate genes linked to the neurobiology of major depressive disorder in the North-Western population of Pakistan. We performed a case-control analysis, with 400 MDD and 232 controls. A trained psychiatrist or clinical psychologists evaluated the patients. Six polymorphisms were genotyped and tested for allele and genotype association with MDD. There were no statistical variations between MDD patients and healthy controls for genotypic and allelic distribution of all the polymorphisms observed. Thus, our analysis does not support the major role of these polymorphisms in contributing to MDD susceptibility, although it does not preclude minor impact. The statistically significant correlation between six polymorphisms and major depressive disorder in the studied population was not observed. There are inconsistencies in investigations around the world. Future research, including GWAS and association analysis on larger scale should be addressed for further validation and replication of the present findings.

A novel variant in the DSE gene leads to Ehlers-Danlos musculocontractural type 2 in a Pakistani family.

The Ehlers-Danlos syndrome (EDS) is a group of heritable connective tissue disorders. Common features of EDS include skin hyperextensibility, articular hypermobility, and tissue fragility. It is classified into 13 subtypes, caused by variations of more than 19 different genes. Among these two subtypes, EDS musculocontractural type 1 (EDSMC1/mcEDS-CHST14; MIM# 601776) is caused by biallelic mutations in the CHST14 gene (MIM# 608429) on chromosome 15q14 and EDS musculocontractural type 2 (EDSMC2/mcEDS-DSE;MIM#615539) is caused by a mutation in DSE (MIM# 605942) on chromosome 6q22. In this study, clinical and molecular diagnoses have been performed for a consanguineous Pakistani (Pakhtun) family with five affected siblings, presenting mcEDS-DSE phenotype. Whole-exome sequencing analysis identified a novel homozygous DSE variant (NM_001080976.1; c.2813T>A, p.Val938Asp) in the proband. Sanger sequencing in all available affected members and their obligate carriers confirmed autosomal recessive segregation of the diseased allele. To the best of our knowledge, this variant identified is novel and expands the DSE pathogenicity leading to EDS, musculocontractural type 2. The result obtained has the potential to help in early diagnosis, genetic counseling, and possible therapeutic inventions.

Pattern and Outcome of Dengue Fever in a Pediatric Tertiary Hospital: A Retrospective Report.

Introduction For Pakistan, dengue has been established as a public health problem. With superimposed factors such as poor socioeconomic conditions, limited public health awareness, poor hygiene, and sanitation conditions, the situation has become more severe and complications have become frequent. Almost 90% of all infections occur in children of age less than 18 years. This is a three-year retrospective report of dengue fever in Southern Pakistan. Methods In this retrospective analysis, all records of patients admitted to the National Institute of Child Health, Karachi, from May 1, 2016, till April 30, 2019, diagnosed with dengue fever were recruited. Their demographic, clinical, and biochemical records were assessed. The outcome was also recorded. Data were entered and analyzed using Statistical Package for Social Sciences (SPSS) for Windows version 20.0 (IBM Corp., Chicago). Results Among 93 cases of dengue fever, there were 71 (76.3%) male and 22 (23.7%) female children. Their mean age was 5.7 ± 3.07 years. The mean duration from onset of disease to hospitalization was 4.2 ± 2.1 days. The mean platelet count was 47391.30 ± 41370.61 x 109/L. Fever (100%) and abdominal pain (35.5%) were common presentations. Bleeding episodes were seen in 31% of children, rash in 15%, disseminated intravascular coagulation in 3%, and 1% developed pleural effusion. There were no mortalities; 87 (93.5%) were discharged and six (6.5%) children left against medical advice. Conclusion Fever, abdominal pain, bleeding episodes, and rash were common presentations. Hematological, hepatological, neurological, and pleural complications were not uncommon. The outcome of the disease was adequate and there were no mortalities.

Melanoma treatment via non-specific adhesion of cancer cells using charged nano-clays in pre-clinical studies.

The incidence of malignant melanoma has rapidly increased in the last two decades. There are many challenges associated with the current conventional therapies, including tumour size and location, the specificity of treatments, tumour resistance, non-mutually exclusive mutations, drug resistance, and many adverse side effects. Due to conventional therapies having several limitations, we have explored an alternative therapy such as nano-clays; nano-sized natural materials originating from clay fraction of the soil. Recently, clay nanoparticles have increasingly been used as a drug carrier for cancer treatment due to their high absorption, ability to engulf microbes, and low toxicity. In this study, we evaluated the effects of a nano-clays mix on melanoma cell proliferation and cell viability in vitro and melanoma growth in vivo xenograft animal model. The in vitro study revealed that nano-clay treatments significantly reduced melanoma cell proliferation and cell viability in a dosage-dependent manner. The in vivo tumour xenograft model demonstrated that nano-clay mix treatment led to significantly reduced tumour size and weight, decreased tumour cell mitosis, and induced tumour necrosis. These processes owe to the most probable changes in the membrane potential of the cancer cells once nano-clays bind with the former through the high non-specific adhesion characteristic of the cancer cells. As the data suggest an important role of nano-clays as an inhibitor of melanoma cell proliferation and survival, these prove to be a natural and effective medicine for the treatment of melanoma. The proven compatibility of nano-clays with the human cells with little side-effects makes them a highly preferred choice for the treatment of melanoma and probably other types of cancers.

The validity of laser diffraction system to reproduce hydrometer results for grain size analysis in geotechnical applications.

The grain size analysis plays a significant role in any geotechnical study. The grain size analysis, by means of sieving, is usually used for coarse material of particle size > 75 µm. For the fine material; the sedimentation methods are frequently adopted (e.g., hydrometers). Other methods also exist such as electron microscopy, digital image analysis and laser diffraction. The fine geomaterials commonly undergo agglomeration which makes the recognition of individual grain size using digital image analysis or electron microscopy challenging. To facilitate and enhance the grain-size analysis, this study was conducted using the Laser Diffraction System (LDS). Seven samples with different nature (composition and texture) and sources were analyzed by hydrometer and LDS. For LDS, various factors were studied such as air pressure, sonication, dilution, refractive index, and distribution method (volume or number). The results were compared qualitatively and quantitatively based on soil classification systems, fractal dimensions, and other parameters. Furthermore, this study provided a novel criterion to determine which LDS distribution method (volume or number) is to be used depending on the Liquid Limit. A combined sieve-LDS system is recommended to obtain the entire grain size distribution. It is concluded that the LDS is a viable technique that can replace the time-consuming hydrometer method to assess the grain-size distribution.

Tunisian Consensus document on magnetic resonance imaging in patients with intracardiac devices.

INTRODUCTION: Patients with ferromagnetic cardiac devices, particularly cardiac implantable electronic devices (CIED) such as pacemakers or implantable cardioverter defibrillators, are often inappropriately deprived of magnetic resonance imaging (MRI) for safety reasons. This consensus document is written by a multidisciplinary working group involving rhythmologists, interventional cardiologists, echocardiographists and radiologists. Its objective is to establish good practice recommendations to optimize the management of patients with cardiac devices requiring MRI examination, while ensuring their safety and facilitating their access to MRI.

Nano-clays as Potential Pseudo-antibodies for COVID-19.

Despite several efforts, the development of an effective vaccine for COVID-19 may take a much longer time. Traditional/natural medicine, already experienced by humans, could be an earlier solution. Considering the research team's experience in using nano-clays as high-affinity material for cancer metastasis, melanoma treatment, and bone regeneration, we propose to use these nano-clays for the prevention/treatment of COVID-19. Owing to high affinity, nano-clays would capture the viruses before the latter get engaged with human hACE2. In this study, molecular-level simulations and modeling of the interaction of coronavirus spike and hACE2 proteins were performed with and without nano-clays. The results showed a very high level of affinity/cohesiveness among SARS-CoV-2 spike and nano-clays as compared to the one between the former and hACE2. We premise that these nano-clays since already being used as drug carriers could also be injected as "clays-alone" medicine. Recommendations have also been provided for future in vitro and in vivo studies.

Review of Non-Destructive Civil Infrastructure Evaluation for Bridges: State-of-the-Art Robotic Platforms, Sensors and Algorithms.

The non-destructive evaluation (NDE) of civil infrastructure has been an active area of research in recent decades. The traditional inspection of civil infrastructure mostly relies on visual inspection using human inspectors. To facilitate this process, different sensors for data collection and techniques for data analyses have been used to effectively carry out this task in an automated fashion. This review-based study will examine some of the recent developments in the field of autonomous robotic platforms for NDE and the structural health monitoring (SHM) of bridges. Some of the salient features of this review-based study will be discussed in the light of the existing surveys and reviews that have been published in the recent past, which will enable the clarification regarding the novelty of the present review-based study. The review methodology will be discussed in sufficient depth, which will provide insights regarding some of the primary aspects of the review methodology followed by this review-based study. In order to provide an in-depth examination of the state-of-the-art, the current research will examine the three major research streams. The first stream relates to technological robotic platforms developed for NDE of bridges. The second stream of literature examines myriad sensors used for the development of robotic platforms for the NDE of bridges. The third stream of literature highlights different algorithms for the surface- and sub-surface-level analysis of bridges that have been developed by studies in the past. A number of challenges towards the development of robotic platforms have also been discussed.

Assessement of stress induced by high-fidelity simulation sessions among medical students.

INTRODUCTION: Simulation is a growing pedagogical method in training health professionals. The use of high-fidelity simulators may be associated with significant stress. OBJECTIVE: to measure self-assessed intensity of stress before and after a planned simulation training session of a third degree atrio-ventricular block  among  medical students. METHODS: A sample of 30 students participating in a high-fidelity simulation training course (10 playing the role of team leader and 20 in the role of medical intern) was studied. Stress was evaluated by self-assessment using a numerical scale before and after the session. The peri-traumatic distress inventory was used to measure the level of distress experienced by the participants. RESULTS: The median stress score was 3, 5±2, 4 before and 6, 2±2, 4 after the simulation session (p<0.001). Stress intensity increased significantly after the session in students playing the role of the team leader than those playing the role of medical intern (8, 4±0, 8 versus 5, 2±2, 3 p<0.001).The average score for peri-traumatic distress inventory was also significantly higher in the team leaders (18, 8±10, 4 Vs 9, 2±3, 7 p=0,022). CONCLUSION: Simulation-induced stress, as measured by self-assessment, increased significantly after the session and was influenced by the role to be played during the scenario.  Stress should be taken into account before debriefing.

Relationship between Galectin-3 levels and severity of coronary artery disease in ST elevation myocardial infarction.

BACKGROUND: Galectin-3 is a new biomarker assumed to reflect fibrogenesis and inflammation. We aimed to investigate the relation of Gal-3 with the severity of coronary artery disease in patients with ST elevation myocardial infarction. METHODS: The prospective study enrolled 62 patients with ST elevation myocardial infarction who underwent coronary angiography. The burden of atherosclerosis was assessed by the number of involved vessels, the number of coronary lesions with a stenosis diameter more than 50% and the Gensini score. Gal-3 levels were measured on admission on miniVIDAS (BioMérieux). RESULTS: The mean age of the patients was 56±11 years old; 93.5% were males. Diabetes, hypertension and hyperlipidemia were respectively 29%, 35.5% and 24.2%. Among patients, 80.6% were active smokers. Mean level of Gal-3was 17±11 ng/ml and didn't differ significantly from the number of involved coronary vessels (p=0.82) and the Gensini score (p=0.4). There was a positive correlation between the number of coronary lesions with a stenosis diameter greater than 50% and Gal-3 (p=0.04). CONCLUSION: In patient with ST elevation myocardial infarction we found a positive correlation between the number of coronary stenosis and Gal-3 level.

History of medical simulation.

The article starts with a report on the history of medical simulation with some examples, and then it explores the evolution of mannequins and the methods using simulation in medicine, from the beginning to their present use.