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1.
Rezaei Aliabadi, H.; Sepanlou, S. G.; Aliabadi, H. R.; Abbasi-Kangevari, M.; Abbasi-Kangevari, Z.; Abidi, H.; Abolhassani, H.; Abu-Gharbieh, E.; Abu-Rmeileh, N. M. E.; Ahmadi, A.; Ahmed, J. Q.; Rashid, T. A.; Naji Alhalaiqa, F. A.; Alshehri, M. M.; Alvand, S.; Amini, S.; Arulappan, J.; Athari, S. S.; Azadnajafabad, S.; Jafari, A. A.; Baghcheghi, N.; Bagherieh, S.; Bedi, N.; Bijani, A.; Campos, L. A.; Cheraghi, M.; Dangel, W. J.; Darwesh, A. M.; Elbarazi, I.; Elhadi, M.; Foroutan, M.; Galehdar, N.; Ghamari, S. H.; Nour, M. G.; Ghashghaee, A.; Halwani, R.; Hamidi, S.; Haque, S.; Hasaballah, A. I.; Hassankhani, H.; Hosseinzadeh, M.; Kabir, A.; Kalankesh, L. R.; Keikavoosi-Arani, L.; Keskin, C.; Keykhaei, M.; Khader, Y. S.; Kisa, A.; Kisa, S.; Koohestani, H. R.; Lasrado, S.; Sang-Woong, L.; Madadizadeh, F.; Mahmoodpoor, A.; Mahmoudi, R.; Rad, E. M.; Malekpour, M. R.; Malih, N.; Malik, A. A.; Masoumi, S. Z.; Nasab, E. M.; Menezes, R. G.; Mirmoeeni, S.; Mohammadi, E.; javad Mohammadi, M.; Mohammadi, M.; Mohammadian-Hafshejani, A.; Mokdad, A. H.; Moradzadeh, R.; Murray, C. J. L.; Nabhan, A. F.; Natto, Z. S.; Nazari, J.; Okati-Aliabad, H.; Omar Bali, A.; Omer, E.; Rahim, F.; Rahimi-Movaghar, V.; Masoud Rahmani, A.; Rahmani, S.; Rahmanian, V.; Rao, C. R.; Mohammad-Mahdi, R.; Rawassizadeh, R.; Sadegh Razeghinia, M.; Rezaei, N.; Rezaei, Z.; Sabour, S.; Saddik, B.; Sahebazzamani, M.; Sahebkar, A.; Saki, M.; Sathian, B.; SeyedAlinaghi, S.; Shah, J.; Shobeiri, P.; Soltani-Zangbar, M. S.; Vo, B.; Yaghoubi, S.; Yigit, A.; Yigit, V.; Yusefi, H.; Zamanian, M.; Zare, I.; Zoladl, M.; Malekzadeh, R.; Naghavi, M..
Archives of Iranian Medicine ; 25(10):666-675, 2022.
Artículo en Inglés | EMBASE | ID: covidwho-20241919

RESUMEN

Background: Since 1990, the maternal mortality significantly decreased at global scale as well as the North Africa and Middle East. However, estimates for mortality and morbidity by cause and age at national scale in this region are not available. Method(s): This study is part of the Global Burden of Diseases, Injuries, and Risk Factors study (GBD) 2019. Here we report maternal mortality and morbidity by age and cause across 21 countries in the region from 1990 to 2019. Result(s): Between 1990 and 2019, maternal mortality ratio (MMR) dropped from 148.8 (129.6-171.2) to 94.3 (73.4-121.1) per 100 000 live births in North Africa and Middle East. In 1990, MMR ranged from 6.0 (5.3-6.8) in Kuwait to 502.9 (375.2-655.3) per 100 000 live births in Afghanistan. Respective figures for 2019 were 5.1 (4.0-6.4) in Kuwait to 269.9 (195.8-368.6) in Afghanistan. Percentages of deaths under 25 years was 26.0% in 1990 and 23.8% in 2019. Maternal hemorrhage, indirect maternal deaths, and other maternal disorders rank 1st to 3rd in the entire region. Ultimately, there was an evident decrease in MMR along with increase in socio-demographic index from 1990 to 2019 in all countries in the region and an evident convergence across nations. Conclusion(s): MMR has significantly declined in the region since 1990 and only five countries (Afghanistan, Sudan, Yemen, Morocco, and Algeria) out of 21 nations didn't achieve the Sustainable Development Goal (SDG) target of 70 deaths per 100 000 live births in 2019. Despite the convergence in trends, there are still disparities across countries.Copyright © 2022 Academy of Medical Sciences of I.R. Iran. All rights reserved.

2.
Pakistan Armed Forces Medical Journal ; 72:S795-S799, 2022.
Artículo en Inglés | Scopus | ID: covidwho-2277849

RESUMEN

Objective: The purpose of this study was to assess willingness to receive COVID-19 vaccine in Pakistan and to understand the reasons causing hesitation towards vaccine administration. Study Design: A cross-sectional study was done through an online survey that was created using google forms. Place and Duration of Study: The study was conducted online from Mar to Aug 2021 in different cities of Pakistan employing nonprobability convenience sampling technique. The link to the questionnaire was shared on different social media platforms such as WhatsApp and Facebook. Methodology: Any individual over the age of 16 and willing to fill the questionnaire was enrolled. Questionnaire used were standardized Oxford COVID-19 vaccine hesitancy scale to assess intent and Oxford general vaccine hesitancy scale to assess attitude towards vaccinations in general. SPSS v25 was used for data analysis. Results: A total of 589 valid responses were finally analyzed. Among the respondents, 24%(141) showed at least some hesitancy regarding COIVD-19 vaccination and 9%(53) of the respondents showed extreme hesitancy. The Pearson correlation coefficient indicated a significant positive correlation (p<0.000) between hesitancy to childhood vaccines and COVID vaccine hesitancy. There was also a significant correlation (p<0.000) between belief in conspiracy's related to COVID-19 virus and refusal to get vaccinated. Conclusion: Vaccine hesitancy is present in roughly 1/4th of the study population. Conspiracy theories and low vaccine acceptance among the general public pose a severe danger to COVID-19 vaccination success. Public vaccine education programs should be started to educate the public regarding their fear of vaccination. © 2022, Army Medical College. All rights reserved.

3.
Journal of Information Technology Teaching Cases ; 2023.
Artículo en Inglés | Scopus | ID: covidwho-2248334

RESUMEN

Morocco is an African country containing a very large market for e-commerce, which further expanded during the 2020–2022 COVID-19 pandemic. However, a few obstacles, like low internet penetration and lack of digital payment systems, are acting as obstacles for the local e-commerce service providers to reach potential in the country. Chari is one such B2B company whose operations changed the landscape of logistics and distribution among the FMCG businesses in Morocco. The company also exercises a B2B2C model, which it achieved through acquiring Karny.ma and Axa Credit, enabling its customers to use a lending and financial transaction tracking model. However, the industry is quite competitive, with offline retailers like TradeDepot, WaystoCap (acquired by MaxAB), and Sokowatch deciding to exploit the possibilities online. Apart from the rising competition, Chari still faces challenges in additional expansion due to the improper and inadequate infrastructure of the country. However, if it can overcome the external threats and utilize the geographical location of Morocco to its advantage, Chari has enormous potential to flourish both locally and globally. © Association for Information Technology Trust 2023.

4.
Int J Tuberc Lung Dis ; 26(9): 897-901, 2022 09 01.
Artículo en Inglés | MEDLINE | ID: covidwho-2248333
6.
Microbial Biosystems ; 6(1):1-8, 2021.
Artículo en Inglés | GIM | ID: covidwho-2204958

RESUMEN

Viruses are one of the main reasons that cause healthy cells to proliferate and become cancerous. Several viruses have been identified as causative factors for various forms of cancer. Tumor occurrence can be caused by viral oncoprotein activity, persistent infection or inflammation. The molecular process is still complicated to be understood. In recent decades, Homo sapiens cell microRNA (hsa-miRNA) has been discovered by small non-coding RNAs that affect post-transcriptional gene expression. hsa-miRNA is a key control factor for several key biological processes and has a much greater impact on the target gene group. even though they occupy a small part of the genome, they play a great role in the development of cancer. Several viruses produce this tiny RNA, which can regulate their gene expression or affect the host's gene expression. A new hypothesis is that Epstein-Barr virus (EBV) is the first cancer causing virus that is found to produce microRNAs (v-miRNAs). In addition, evidence shows that miRNA encoded by EBV contributes to the occurrence and progression of EBV-related malignancies. Generally, these compounds reduce messenger RNA (mRNA) instability, such as genes that regulate tumorigenesis mechanisms like inflammation, cell cycle control, stress response, differentiation, apoptosis, invasion, and immune pathways. Therefore, EBV-miRNAs are important in the complex interaction between host, virus and EBV tumorigenesis. In terms of malignant tumors, the combinatorial process behind EBV-miRNA still needs further study. In this article, we will introduce EBV-miRNA, including the cellular processes affected by the virus, and their ability to promote cancer.

7.
Asian Journal of Chemistry ; 34(11):2786-2796, 2022.
Artículo en Inglés | Scopus | ID: covidwho-2111013

RESUMEN

Medicinal plants or medicinal herbs possess therapeutic properties or exert beneficial pharmacological effects on human. From time immemorial, people have been using various medicinal plants without even knowing their phytochemistry and pharmacological properties as a medicine for treating numerous ailments. As technology developed and upgraded, people used to screen out various phytoconstituents as well as evaluate their basic pharmacological properties. Tinospora cordifolia is a medicinal herb which is commonly known as Giloy belong to family menispermaceae. It can also be found in places like Africa, China, South-East Asia, Indo-Malaya region and Australia. Traditionally, people use this herb as prominent food materials due to their higher nutraceutical value and various healing properties. For phytochemical investigation, extraction of whole plant is preferable whereas most of the phytochemical are found to be present in leaves. Various potent phytochemicals are found in this herb such as tinosponone, tinocordiside, tinosporaside, cordifoliside, β-sitosterol, mekisterone A, etc. which are belong to class of alkaloids, sesquiterpenoids, glycosides, steroids, volatile oil, etc. Owing to the presence of these potent compounds, it exhibits wide range of large number of pharmacological activities such as antiviral, antibacterial, antifungal, antioxidant, antidiabetic, anticancer activities, etc. In past two years, SARS-CoV-2 infections has taken life of millions of people across the globe and there were no any vaccine or proper antiviral medicine available to defend this deadly pandemic, hence people were mostly relying on herbal plant therapy. Giloy is one such magical herb which exhibit healing properties in SARS-CoV-2 infected patients. Moreover, in-silico studies have been carried out to determine the binding affinity as well as inhibiting potential of various phytoconstituents of giloy. In this review work, we compiled all the updated information about T. cordifolia as well as emphasizing more on SARS-CoV-2 inhibiting potential. © 2022 Chemical Publishing Co.. All rights reserved.

8.
Arab Gulf Journal of Scientific Research ; 2022.
Artículo en Inglés | Scopus | ID: covidwho-2078032

RESUMEN

Purpose: The paper intends to explore the lived experiences of medical students during the COVID-19 pandemic and its impact on their lifestyles and mental wellbeing. Design/methodology/approach: Fourteen medical students from the College of Medicine and Medical Sciences, Arabian Gulf University, Bahrain, were enrolled, and their narratives were obtained. Data were analyzed and conducted using Colaizzi’s phenomenological descriptive method of enquiry. Findings: The analysis identified two themes, along with nine subthemes, that were generated. The first theme focused on mental and social experiences, while the second focused on lifestyle changes. During the pandemic, students had time to reflect on themselves and started to think positively about their lives, although they felt fearful, uncertain, stressed and anxious due to preventive control measures that were mandated, including social distancing and lockdowns. Participants’ lifestyles changed generally negatively, as they adapted to the preventive measures, rendering them physically inactive and exposing them to unhealthy food and disturbed sleep. Originality/value: The findings provide an insight into the negative impact of the COVID-19 pandemic on the lifestyle and mental wellbeing of medical students. Educational institutes need to offer their students both short as well as long-term health, social and mental support to overcome the impact of the pandemic on their lives. © 2022, Salman Alzayani, Khaldoon Al-Roomi and Jamil Ahmed.

9.
Virtual Learning: Insights and Perspectives ; : 51-63, 2022.
Artículo en Inglés | Scopus | ID: covidwho-2033772

RESUMEN

The current period has forced many sectors to close down, and education is one of it. The pandemic era has dropped the flow of on-going academic courses in educational institutions. The microorganism has created a gap between the learners and the instructors. The mandatory social distancing in the pandemic period has changed the traditional concept of education, from classroom teaching to anywhere learning. The achievement from online education is debatable but it promises to be the step for democratizing the current education system. As now, online platform is the only source of knowledge and education for students, implementing online classes in educational institutions will not only provide knowledge on the subject matter but will also help them to complete their academic courses during this pandemic period (COVID 19). This study is undertaken on various online applications such as Google classroom, Zoom app, College app etc. This study is an attempt to analyze the problems and prospects of higher education institutions which arises while implementing these online platforms in the higher education institutions especially during this lockdown period. © 2023 Contributors and Manakin Press. All rights reserved.

10.
Economics Bulletin ; 42(1):60-68, 2022.
Artículo en Inglés | Scopus | ID: covidwho-1929397

RESUMEN

In this study, we analyze the impact of the Covid-19 pandemic on bilateral trade using monthly data from January to June 2020. Imports of the OECD member states are analyzed using a structural gravity model of trade estimated with the Poisson pseudo maximum likelihood estimator. The analysis is conducted for total imports and for fruit and vegetables. Our findings show a significantly negative impact of the pandemic on both import measures, which is more pronounced for the perishable goods than for aggregate imports. © 2022. Economics Bulletin. All Rights Reserved.

11.
Microbial Biosystems ; 5(2):1-8, 2020.
Artículo en Inglés | GIM | ID: covidwho-1904085

RESUMEN

SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus 2) is RNA virus with a positive-sense single-strand that belongs to the beta-coronavirus group that causes COVID-19 (Coronavirus Disease 2019) which originally emerged in China. Viruses with RNA genomes are known by a high mutation rate potential. The mutation rate determines genome variability and evolution of the virus;therefore, allowing viruses to evade the immune system, gain more infectivity potentials, virulence modifications, and probably resistance development to antivirals. A total of 311 SARS-CoV-2 virus whole genome sequences have been retrieved from the GISAID database from 1st of January 2020 to 31th of August 2020. The sequences were analyzed for sequence purity and multiple sequence alignment together with reference sequence was conducted through using Clustal Omega that is imbedded in Jalview software and Blast tools. We recorded the occurrence of 4 newly incident high frequently occurring mutations in all six geographic regions, namely at positions 2416, 18877, 23401, and 27964. The majority of all recorded hotspots were detected in Asia, Europe, and North America. The findings of our study suggest that the SARS-CoV-2 is in continuous evolution. For the impact of these mutations, further investigations are required and to understand whether these mutations would lead to the appearance of Drug-resistance viral strains, strains with increased infectivity and pathogenicity, and also their effect on the vaccine development and immunogenesis.

12.
Journal of the American College of Cardiology ; 79(9):2545-2545, 2022.
Artículo en Inglés | Web of Science | ID: covidwho-1848269
13.
Ann R Coll Surg Engl ; 2022 Apr 21.
Artículo en Inglés | MEDLINE | ID: covidwho-1808512

RESUMEN

INTRODUCTION: The COVID-19 pandemic has led to wide-ranging disruption of head-neck cancer (HNC) service provision in the UK. Early reports suggest delays in referral, diagnosis and initiation of treatment for new cancer cases compared with before the pandemic. METHODS: The HNC service was studied retrospectively for the time-periods between 1 January 2020 to 31 October 2020 (hereafter 'post-COVID') and 1 January 2019 to 31 October 2019 (hereafter 'pre-COVID'). We analysed: (1) the number of cases treated at our centre, (2) stage of disease at presentation and (3) treatment delivery times. RESULTS: In the post-COVID period, the total number of HNC cases treated decreased (48 vs 56 pre-COVID). There was increase in advanced stage at presentation (58% vs 42% pre-COVID) and a significant increase in the need for airway stabilisation (13 vs 5 pre-COVID; p=0.03). Average time from referral to treatment was significantly prolonged (72.5 days vs 49.23 days pre-COVID; p=0.03). Two-week wait referrals were seen in HNC clinics at median time of 11.9 days, compared with 7.1 days during the pre-COVID period (p=0.07). However, there was no delay in the initiation of first treatment after the decision to treat (29.2 days vs 24.7 days pre-COVID; p=0.58). CONCLUSION: The results of this study call for early referral at the primary care level and rapid radiopathological confirmation at the tertiary level to prevent delays in diagnosis of new HNC cases.

14.
International Conference on Emergent Converging Technologies and Biomedical Systems, ETBS 2021 ; 841:651-662, 2022.
Artículo en Inglés | Scopus | ID: covidwho-1787773

RESUMEN

Coronavirus infection (COVID-19) is an extremely contagious infection produced by severe acute respiratory coronavirus syndrome 2. The infection started in Wuhan, China, in December 2019, and has extended worldwide to more than 200 countries since then. The effect is such that the World Health Organization (WHO) has announced a Global Health Emergency of International Significance on the present pandemic of COVID-19. As many countries gets affected by this rampant virus, it is important for the healthcare workers to keenly observe every patient and give the accurate results like if they been affected or not. As we know healthcare worker are the real worriers as they sacrifice their lives to save others, so helping them with advance technologies will be a big deal. So, in this paper a CNN model is been used for precisely classify patients as they are affected or not. Experimentation results depicts that the proposed model attains an accuracy of 93.9%. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

15.
British Journal of Surgery ; 109(SUPPL 1):i63, 2022.
Artículo en Inglés | EMBASE | ID: covidwho-1769148

RESUMEN

Aim: Remote consultations (RC) were implemented during the COVID-19 pandemic with the aim of preventing transmission of the virus. We conducted a survey to assess patients' and clinicians' satisfaction of RC. Method: Two online surveys were created for patient and clinician feedback, and each recorded a cohorts' opinions on various aspects of RC. The surveys were distributed to Urology, General and Vascular surgery departments at three NHS trusts. Patient feedback was collected over the phone, whilst clinicians completed the survey online. Results: Overall, responses from 99 patients and 22 clinicians were collected. 89.9% of patients were either 'satisfied or very satisfied' with RC, compared to 77.2% of clinicians who practiced RC. 93.9 % of patients felt they were able to discuss all their concerns during their RC. However, outside of the COVID-19 setting 50% of patients and 59.1% of clinicians would prefer face to face consultations. Both cohorts reported adherence to social distancing and convenience as key advantages of RC;furthermore 68.2% of clinicians thought RC were economically beneficial. 100% of clinicians felt the inability to examine patients was a disadvantage of RC and 33.8% of patients agreed with this. Conclusions: The majority of feedback from patients and clinicians was positive for RC. However, in future approximately 55% of both cohorts would prefer face to face consultations. Looking forward, we believe RC can form a part of routine practice in selected groups of patients, where it could potentially save time and money without compromising patient or clinician satisfaction.

16.
Small Enterprise Research ; 28(1):75-82, 2021.
Artículo en Inglés | Scopus | ID: covidwho-1709584

RESUMEN

This practitioner paper presents the case of a small paper business named JNA Pulp, initiated with the vision to provide high-quality imported paper to the market. The paper discusses several hurdles faced by the company which eventually pushed the owner to contemplate shutting down the business in the first quarter of 2020. With the rise of COVID-19, it was clear that considering the stance of the business in local market, survival would be impossible. Using the Fishbone analysis, the paper analyses the problems that lead to the closure of this business in April 2020 and further evaluates the strategies that could possibly contribute towards the survival of small businesses in the domestic market. © 2021 Informa UK Limited, trading as Taylor & Francis Group.

17.
Ann R Coll Surg Engl ; 104(9): 694-699, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: covidwho-1690829

RESUMEN

INTRODUCTION: Cadaveric dissection courses have come to a standstill since the onset of the COVID-19 pandemic. In addition to limited operative opportunities, cancellation of such courses has severely impacted surgical training, especially in a craft-based specialty such as head-neck surgery. The aim of this educational project was to: (1) study the feasibility of an in-person head-neck cadaveric dissection course during COVID-19 pandemic; and (2) validate the educational benefit of this teaching method to ear, nose and throat (ENT) trainees. METHODS: We developed a 2-day head-neck cadaveric dissection course for ENT trainees. The course programme covered essential head-neck open surgical procedures. Content validity (subjective feedback) was assessed using a 5-point Likert scale. Construct validity (objective usefulness) was evaluated via two pre- and post-course questionnaires, estimating knowledge of head-neck surgical anatomy and self-assessment of levels of confidence with head-neck procedures, respectively. RESULTS: A risk assessment was conducted and a protocol developed (risk was deemed to be low/tolerable). Content validity showed high satisfaction compared with a median Likert score of 3, 'average' (p=0.000002). For construct validity, the mean score per question improved significantly (p=0.001). Overall levels of confidence showed a trend towards improvement (p=0.08). There was significant improvement in laryngectomy (p=0.01) and level I dissection (p=0.01), with an indication of improvement in level II-V dissection (p=0.07). CONCLUSIONS: We demonstrated that a cadaveric dissection course, using thorough risk assessment and protocol, could be safely conducted with high content and construct validation during these unprecedented times. This is an invaluable learning environment that needs to be encouraged despite infection control restrictions.


Asunto(s)
COVID-19 , Disección del Cuello , Humanos , COVID-19/epidemiología , Pandemias , Disección , Cadáver , Competencia Clínica
18.
6th International Conference on ICT for Sustainable Development, ICT4SD 2021 ; 321:21-33, 2022.
Artículo en Inglés | Scopus | ID: covidwho-1653383

RESUMEN

This paper deals with opinions expressed in social media, namely Twitter, with respect to the ongoing vaccination program for the novel coronavirus COVID-19. This pandemic has affected almost the entire world because of lockdown and its related impact on personal, economical and emotional levels. During the lockdown, people suffered loneliness and lack of interpersonal interaction therefore resort to taking social media to voice their concerns and emotions. The need for vaccination, its delivery and trust are some of the topics on which sentiments are expressed on Twitter based on which this research is conducted. This study analyses the sentiments of the people in India towards the emergency use authorization of COVID vaccine rollout. The tweets are collected, pre-processed to exclude noise and irrelevant data and then used for sentiment analysis using the Lexicon-based approach and machine learning method. The relative outcome of tweets analysed via all these methods is consistent in each type of sentiment. It is observed that sentiments of most of the tweets came out to be either affirmative or neutral. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

19.
International Journal of Finance & Economics ; : 21, 2022.
Artículo en Inglés | Web of Science | ID: covidwho-1611231

RESUMEN

This study examines how crude oil price volatility affected the stock returns of major global oil and gas corporations during three major oil-price wars that took place between October 1991 and June 2020. Episodes considered include the 1998 Saudi Arabia - Venezuela war, the 2014-2016 conflict and the 2020 Saudi Arabia - Russia war in a time of unprecedented crisis caused by the COVID-19 pandemic. The persistence of volatility in oil prices during times of specific oil-price wars is captured through generalized autoregressive conditional heteroscedasticity (GARCH) model while the leverage effect is tested using the threshold generalized autoregressive conditional heteroscedasticity (T-GARCH) model. Moreover, a vector autoregressive (VAR) model is employed to consider the relationship between oil price shocks and stock returns of oil and gas corporations. Our findings reveal a significant evidence for volatility persistence and leverage effects in oil price during the three oil-price wars. These findings are consistent for WTI as well as Brent crude oil specifications. Though the persistence of volatility is similar to that of the previous two oil-price wars, the 2020 Saudi Arabia - Russia oil-price war has higher volatility spikes than the previous two wars. Besides, oil price shocks have a significant and positive effect on the returns of oil and gas companies. These findings provide investors information on how volatility in global oil prices is also sensitive to irregular events such as price wars between oil producers. This information can be important for economic agents contemplating shorter hedges by managing risks during times of high volatility.

20.
Blood ; 138:999, 2021.
Artículo en Inglés | EMBASE | ID: covidwho-1582345

RESUMEN

Coronavirus disease 2019 (COVID-19) is caused by infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Most infected individuals are asymptomatic or show only mild symptoms, but 20% of infected individuals become severely ill resulting in a 2-5% mortality rate for severe infections. Men, the elderly and patients with comorbidities (such as cardiovascular disease, hypertension, diabetes, and obesity) are more likely to develop severe disease. Clinical features characterizing severe COVID-19 cases include inflammation and thrombosis, but the molecular mechanisms underlying these processes remain elusive. K18 hACE2 transgenic mice express the SARSCoV-2 receptor human angiotensin-converting enzyme 2 (hACE2) under the control of the human cytokeratin 18 (K18) promoter. K18 hACE2 mice express hACE2 in airway epithelial cells and are susceptible to SARS-CoV-1 and SARS-CoV-2 infections. At the dose of 10 5 PFU/mouse, all SARS-CoV-2-infected K18 hACE2 mice rapidly lose weight and succumb to viral infection by 5-6 days post infection. Morbidity and mortality correlated with SARS-CoV-2 replication in the nasal turbinates and lungs. Notably, susceptibility was highly associated with a local and systemic cytokine/chemokine storm. SARS-CoV-2 infection in K18 hACE2 mice recapitulates many of the pathological findings observed in human patients offering a reliable animal model for the study of SARS-CoV-2 pathogenesis. Infection with a lower viral dose (10 4 and 2.5x10 3 PFU/mouse) prolongs the symptomatic phase of the infection, postponing time of death up to 16 days post infection (mortality rate at 10 4 PFU: ~40% in females, 100% in males;mortality rate at 2.5x10 3 PFU: ~30% in females, ~55% in males). At these lower viral doses, K18 hACE2 mouse males exhibited both increased susceptibility to the SARS-CoV-2 infection and more severe disease. Male mice showed increased mortality associated with an increase in weight loss and decrease in body temperature. Disease characteristics showed striking similarities with reported human COVID-19 cases, including severely reduced O 2 saturation. The pathogenesis of severe COVID-19 cases involves both virus-induced cell damage and secondary tissue damage due to a vicious cycle of dysregulated - hyperactive coagulation and inflammatory pathways that present as “a cytokine storm”, endothelial dysfunction, and “immunothrombosis”. Analysis of murine plasma analytes from infected mice revealed additional pathogenetic features resembling SARS-CoV-2 infection in humans. High circulating D-dimer levels are now considered a main predictor of poor outcome of SARS-CoV-2 infection. Notably, we also observed a progressive increase of circulating D-dimer levels in the plasma of K18 hACE2 infected mice peaking at day 7 post infection, suggestive of a hypercoagulable state. Moreover, similar to humans, the increase in soluble thrombomodulin plasma concentration and its correlation with disease severity was indicative of endothelial activation and dysfunction in K18 hACE2 infected mice. SARS-CoV-2 infection-induced changes of coagulation and endothelial activation in mice resulted in a biphasic alteration of endothelial permeability where an initial increase in vascular permeability, peaking at day 5 post infection, was followed by a sudden decrease in Evan's blue dye extravasation in the lung parenchyma and characterized by the appearance of areas of hemorrhagic infarction indicative of thrombotic events. Altogether, our results identify the K18 hACE2 transgenic mouse as an important small animal model to study the molecular mechanisms involved in the derangement of the finely tuned interaction between the immune and coagulation systems associated with severe cases of SARS-CoV-2 infections. Disclosures: Mosnier: Hematherix: Membership on an entity's Board of Directors or advisory committees;Coagulant Therapeutics: Research Funding.

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