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1.
Microbiology Spectrum ; 10(1):17, 2022.
Article in English | Web of Science | ID: covidwho-1790333

ABSTRACT

The Amazonas was one of the most heavily affected Brazilian states by the COVID-19 epidemic. Despite a large number of infected people, particularly during the second wave associated with the spread of the Variant of Concern (VOC) Gamma (lineage P.1), SARS-CoV-2 continues to circulate in the Amazonas. To understand how SARS-CoV-2 persisted in a human population with a high immunity barrier, we generated 1,188 SARS-CoV-2 whole-genome sequences from individuals diagnosed in the Amazonas state from 1st January to 6th July 2021, of which 38 were vaccine breakthrough infections. Our study reveals a sharp increase in the relative prevalence of Gamma plus (P.1+) variants, designated Pango Lineages P.1.3 to P.1.6, harboring two types of additional Spike changes: deletions in the N-terminal (NTD) domain (particularly Delta 144 or Delta 41-144) associated with resistance to anti-NTD neutralizing antibodies or mutations at the S1/S2 junction (N679K or P681H) that probably enhance the binding affinity to the furin cleavage site, as suggested by our molecular dynamics simulations. As lineages P.1.4 (S:N679K) and P.1.6 (S:P681H) expanded (Re > 1) from March to July 2021, the lineage P.1 declined (Re < 1) and the median Ct value of SARS-CoV-2 positive cases in Amazonas significantly decreases. Still, we did not find an increased incidence of P.1 variants among breakthrough cases of fully vaccinated patients (71%) in comparison to unvaccinated individuals (93%). This evidence supports that the ongoing endemic transmission of SARS-CoV-2 in the Amazonas is driven by the spread of new local Gamma/P.1 sublineages that are more transmissible, although not more efficient to evade vaccine-elicited immunity than the parental VOC. Finally, as SARS-CoV-2 continues to spread in human populations with a declining density of susceptible hosts, the risk of selecting more infectious variants or antibody evasion mutations is expected to increase. IMPORTANCE The continuous evolution of SARS-CoV-2 is an expected phenomenon that will continue to happen due to the high number of cases worldwide. The present study analyzed how a Variant of Concern (VOC) could still circulate in a population hardly affected by two COVID-19 waves and with vaccination in progress. Our results showed that the answer behind that was a new generation of Gamma-like viruses, which emerged locally carrying mutations that made it more transmissible and more capable of spreading, partially evading prior immunity triggered by natural infections or vaccines. With thousands of new cases daily, the current pandemics scenario suggests that SARS-CoV-2 will continue to evolve and efforts to reduce the number of infected subjects, including global equitable access to COVID-19 vaccines, are mandatory. Thus, until the end of pandemics, the SARS-CoV-2 genomic surveillance will be an essential tool to better understand the drivers of the viral evolutionary process.

2.
IEEE Access ; 2022.
Article in English | Scopus | ID: covidwho-1779060

ABSTRACT

We propose a new concept and architectural design for a double hybrid tailsitter unmanned aerial vehicle with vertical takeoff and landing capability. Basically, it consists of a modified flying wing with a single combustion powertrain set and a multirotor with 2 powertrain sets with electric motors. To this end, we have designed, built, and tested a prototype that spends less energy on vertical taking off and landing and also on horizontal flight, for maximizing flight endurance and distance.With electric propellers fixed at the leading wing edge, the tailsitter has two standard surfaces for elevation control and two vertical stabilizers that are used to give the necessary direction on vertical takeoff and landing. Experiments and results show the versatility of our hybrid tailsitter for operations in a restricted field. We performed several tests starting with the aircraft on the ground in vertical positioning. These tests include executing vertical takeoffs and landing, transitions from vertical to horizontal flight modes and transitions back from horizontal to vertical flight modes, and hovering, which were carried out successfully. Transition fourth and back from combustion to multirotor modes are inherent to some of those flight mode transitions, which have been performed smoothly.We also performed tests (in bench) to estimate the flight endurance. Final autonomous flight adjustments were not performed due to the Covid-19 pandemic caused by SARS-CoV-2. To this end the proposed and currently built prototype has proven to be functional as an effective hybrid UAV system. Author

3.
European Journal of Physics ; 43(3):18, 2022.
Article in English | Web of Science | ID: covidwho-1764480

ABSTRACT

Advanced fitting of ordinary differential equations models to experimental results is presented within the context of different academic levels of students and diverse research fields. In many areas, the analysis of experimental results cannot be restricted to cases where particular solutions of the models' differential equations, valid only for specific limit conditions, apply. In those cases, analytical mathematical equations are not available and a complete description of the systems extends beyond the numerical minimization of statistical estimators, like the chi-square, because it requires solving numerically the models' differential equations. Dedicated fitting procedures that involve the interdependent processes of solving the ordinary differential equations and fitting the numerical solutions to the experimental results are required to obtain the best fitting sets of parameters with consistent physical meaning. A simple, but powerful, web-based ordinary differential equations solver and fitter is presented, and used to analyse both the complete motion of a rigid pendulum and the dynamics of a viral infection.

4.
Boletin Goiano De Geografia ; 41(1):32, 2021.
Article in Portuguese | Web of Science | ID: covidwho-1698758

ABSTRACT

This article has as main goal to discuss the Covid-19 spread due to the mobility of the patients over the urban network in the city of Imperatriz, in Maranhao State. The analyzed time frame refers to the first 100 days of the pandemic, emphasizing the urban network of the Imperatriz city space. The examined data of the ICU, hospital beds and respirators in the State, also the data about the viral evolution in this period. The main data source are the Datasus and the Maranhao State health offil ce. The studied characteristics suggest that the medical-hospital equipment concentration in few cities of the State, especially in Imperatiz, is an expressive bottleneck when fighting the Sars-CoV-2 pandemic, due to the necessity of mobilization of people from the smaller centers with less health services to the ones with more hospital beds, resulting in more spread areas. Therefore, the spread of the disease happens in a graduated way in the urban network of the city, and this data is not always evident in the epidemiologic reports.

5.
MEDLINE;
Preprint in English | MEDLINE | ID: ppcovidwho-326588

ABSTRACT

Reports of new-onset diabetes and diabetic ketoacidosis in individuals with COVID-19 have led to the hypothesis that SARS-CoV-2, the virus that causes COVID-19, is directly cytotoxic to pancreatic islet beta cells. This would require binding and entry of SARS-CoV-2 into host beta cells via cell surface co-expression of ACE2 and TMPRSS2, the putative receptor and effector protease, respectively. To define ACE2 and TMPRSS2 expression in the human pancreas, we examined six transcriptional datasets from primary human islet cells and assessed protein expression by immunofluorescence in pancreata from donors with and without diabetes. ACE2 and TMPRSS2 transcripts were low or undetectable in pancreatic islet endocrine cells as determined by bulk or single cell RNA sequencing, and neither protein was detected in alpha or beta cells from these donors. Instead, ACE2 protein was expressed in the islet and exocrine tissue microvasculature and also found in a subset of pancreatic ducts, whereas TMPRSS2 protein was restricted to ductal cells. The absence of significant ACE2 and TMPRSS2 co-expression in islet endocrine cells reduces the likelihood that SARS-CoV-2 directly infects pancreatic islet beta cells through these cell entry proteins.

6.
European Heart Journal ; 42(SUPPL 1):404, 2021.
Article in English | EMBASE | ID: covidwho-1554035

ABSTRACT

Background: COVID-19 was first considered a pandemic on the 11th of March of 2020 by the World Health Organization. Its impact comprised not only the direct consequences of the disease but a decrease in the follow-up and interventions of patients with cardiovascular (CV) disease. In Portugal and the World, the consequences of this complex paradigm shift on emergent pacemaker implantation rates during and after this pandemic is largely unknown. Purpose: We sought to analyse the impact of COVID-19 pandemic on emergent pacemaker implantation rate and patient profile in a tertiary hospital during the first Portuguese lockdown and subsequent post-lockdown period. Methods: We retrospectively reviewed the clinical profile of patients who had pacemakers implanted in our hospital in an urgent/emergent setting from March 18, 2020 to May 17, 2020 (lockdown) and May 19 to July 17, 2020 (post-lockdown). This data was then directly compared to the homologous periods from the year before (H1 and H2, respectively). Results: A total of 180 patients submitted to emergent pacemaker implantation were included. The cohort was comprised of 29 patients who had a pacemaker implanted during lockdown, 60 post-lockdown, 38 in H1 (+31% vs lockdown) and 53 in H2. Average age and gender proportion were similar for all groups. When comparing lockdown and post-lockdown periods, the number of cases significantly increased in the second period (+106.9%) and there was a tendency for a higher number of temporary pacemaker use (3.4% vs 16.7%;p=0.076). Patients admitted during lockdown were 7.57 times more likely to present with hypotension/shock (odds ratio (OR) 7.57;p=0.013). Regarding lockdown and its homologous 2019 period, there was a decrease in the number of patients admitted (-23.7%). Again, there was a higher tendency for hypotension on presentation during lockdown (p=0.054). In comparison to its homologous 2019 period, post-lockdown saw a slight increase in the number of patients (+13.2%) and more patients presented with bradycardia (16.7% vs 3.8%;p=0.026). Also of note, no patients were admitted to the emergency department during lockdown for anomalies detected on ambulatory tests (Holter, electrocardiogram or implanted loop recorder). Conclusion: During lockdown, clinical presentation was generally more severe, with a greater number of patients presenting with hypotension/ shock. In addition, there appears to be a lockdown effect on emergent bradyarrhtmias admissions in the post-lockdown period with a profound impact: higher admission rates and more severe presentations including a higher need of temporary pacemaker. Patients with symptoms suggestive of bradyarrhythmias should be advised to present promptly regardless of the pandemic. (Figure Presented).

7.
European Heart Journal ; 42:2101-2101, 2021.
Article in English | Web of Science | ID: covidwho-1553233
8.
Brazilian Journal of International Law ; 18(2):56-71, 2021.
Article in Portuguese | Scopus | ID: covidwho-1551763

ABSTRACT

The coronavirus pandemic (Sars-CoV-2) has impacted many aspects of human life and specially the international civil aviation sector. Thus, this research investigates: the existence and extent of a human duty attributed to airline operators to promote health in international commercial passenger flights, regarding the prevention and containment of communicable diseases, in periods of pandemic and return to normality. Therefore, guided by a deductive approach and in the light of the International Theory of Human Duties, the article analyzed: norms of Public International Law about aviation, health and sanitation;as well as judgments from different courts on the subject. Thus, by interpreting the term accident, the possibility of assigning such human duty to airlines was found, whose extension should cover the flight, boarding and disembarking of passengers. In addition, there was a brief analysis of the costs of such a duty, seeking to present alternatives for its costing in society, however, given its relevance, this topic should be analyzed in greater depth in future research. Thus, this article contributes towards, within the scope of international civil aviation, establishing paths aimed at resolving sanitary crises of an unusual magnitude, from the perspective of human duties. © 2021 Centro Universitario de Brasilia. All rights reserved.

10.
Journal of the American Society of Nephrology ; 32:96, 2021.
Article in English | EMBASE | ID: covidwho-1489631

ABSTRACT

Background: Patients under hemodialysis are at higher risk of developing severe complications upon SARS-CoV-2 infection and were prioritized in the Portuguese vaccination campaign. Methods: We performed a longitudinal analysis of antibody responses upon vaccination with BNT162b2 mRNA (Pfizer/BioNTech, Comirnaty) in a cohort of 156 hemodialyzed patients. Direct ELISA was used to quantify IgG, IgM and IgA anti-fulllength Spike antibody levels against calibrated sera from naturally infected patients at three points: day of the first vaccine dose (t0);3 weeks later (day of the second dose, t1), and 3 weeks after the second inoculation (t2) for 143/156 patients. Anti-n was also measured in t0 and patients anti-n positive were excluded. Results: We observed that 90.9% of the patients developed anti-spike IgG antibodies after the second vaccine dose (t2). Seroconversion was remarkably low at t1 after the first vaccine dose with only 29.4% of patients developing anti-spike IgG antibodies. In addition to positivity, the second vaccine dose markedly increased IgG antibody levels. IgA levels were also higher at t2 with 83.9% of the patients achieving positivity while IgM positivity only reached 29.4%. Age showed a significant negative effect on the humoral response at t2 for anti-Spike IgG and for IgM, particularly over 60 years. Further analysis revealed that nine patients under immunosuppression therapies showed significantly lower humoral response along the vaccine schedule (p=0.005 at t1;p=0.008 at t2). Interestingly, the inability to develop anti-HBs antibodies upon hepatitis B vaccination frequently found in hemodialyzed patients was not correlated with lack of responsiveness to SARS-CoV-2 vaccination. Conclusions: The large majority hemodialyzed patients showed a significant humoral response to BNT162b2 mRNA vaccination, but a sizable proportion of patients showed low antibody levels when compared to responses in the general population (medRxiv 2021.03.19.21253680).

11.
Annals of Oncology ; 32:S1147, 2021.
Article in English | EMBASE | ID: covidwho-1432892

ABSTRACT

Background: Cancer patients (pts) have higher risk of severe COVID-19 infection. However, observations are based on non-comparative retrospective studies. Evidence regarding vaccination in cancer pts is limited, but there is enough evidence to support COVID-19 vaccination, even under active treatment. Data on humoral and cellular immune response to antiviral vaccination in cancer pts are scarce. In pts receiving immunosuppressive therapies (IST) like chemotherapy and targeted therapies, seroconversion/protection rates are expected to be lower than general population, but not in pts receiving immune checkpoint inhibitors (ICI). Serum antibodies against an infectious agent may be an immunity indicator. Methods: Prospective observational longitudinal study with the intent of evaluating the humoral response of cancer pts to COVID-19 vaccination. The study includes pts diagnosed in any stage, without or under active treatment, or survivors followed in Hospital Prof. Dr. Fernando Fonseca, in partnership with Instituto Gulbenkian de Ciência. Pts are divided into 4 arms, independently of the vaccine: A – IST;B – ICI;C –Hormone therapy (HT);D – Cancer survivors. Recruitment started in March 2021, expecting at least 50 pts per arm. IgG, IgA and IgM anti-SARS-CoV-2 antibodies ELISA determination in 9 timepoints: before 1st dose and at the 3rd, 6th, 12th, 15th, 24th, 36th, 48th and 60th weeks post 1st dose. Side effects’ questionnaire will be implemented after 1st and 2nd doses. Results: Recruitment is ongoing and a total of 202 pts were enrolled, of which 178 pts have 3-weeks post 1st dose evaluated: 101 in arm A: 11 in B: 31 in C;and 35 in D.The mean age is 61.6 years, with 53.4% females. Regarding vaccines, 55 pts were submitted to ChAdOx1-S/nCoC-19, 5 to Ad26.COV2.S, 89 to BNT162b2 and 12 to mRNA-1273 vaccines. At 3 weeks, 33/97 pts (34%) in arm A, 2/11 pts (18%) in B, 14/28 pts (50%) in C and 15/35 pts (43%) in D already generated anti-spike IgG. Most common side effects were local inflammatory reaction (47%), generalized muscle pain (17%), fatigue (11%), and chills (10%). Conclusions: Efficacy and safety profiles of vaccines against COVID-19 infection in cancer pts is still unknown.This study hopes to assess differences in immunization between pts’ treatment profiles and duration profiles and safety profiles. Legal entity responsible for the study: The authors. Funding: Has not received any funding. Disclosure: All authors have declared no conflicts of interest.

12.
Nephrology Dialysis Transplantation ; 36(SUPPL 1):i527-i528, 2021.
Article in English | EMBASE | ID: covidwho-1402525

ABSTRACT

BACKGROUND AND AIMS: Patients on renal replacement therapy (RRT) pose multiple risk factors that may increase the risk of death from coronavirus disease 2019 (COVID-19). Currently, evidence of incidence, management, and prognosis of COVID-19 in this population are scarce. METHOD: Between May and December 2020, we followed two RRT populations that have the same tertiary hospital in Southern Brazil as its reference hospital for transplantation. Firstly, we monitored eight affiliated dialysis clinics keeping track of COVID-19 incidence and fatality rate in dialysis patients and those on the kidney transplant waiting list. In the same period, we also monitor COVID-19 incidence and mortality among our prevalent population of kidney transplant recipients. RESULTS: We evaluated 1049 patients in RRT in the dialysis centers. COVID-19 occurred in 89 of such patients (8.5%), and 31 died from such condition (35.8% death rate). Fifteen patients (5.45%), among 275 on the kidney transplant waiting list, contracted the virus, with one death (6.6%). Within our prevalent population of 1348 kidney transplant recipients, 113 were diagnosed with COVID19 (incidence: 8.4%), and 17 of them died (mortality rate: 15%). Finally, the number of kidney transplants decreased by 60.4% compared with the same period in the previous year. CONCLUSION: COVID-19 determined a substantial impact on RRT. A high frequency of chronic dialysis patients expired from the disease. The impact on the patients on the transplant waiting list seems to be less pronounced probably due to their better health conditions. The fatality rate in kidney transplant recipients is elevated and probably mostly related to comorbidities. Brazil is currently entering the second wave of the disease and it is crucial to find and provide means to protect such vulnerable populations.

13.
Revista Cientifica Multidisciplinar RECIMA21 ; 2(5), 2021.
Article in Portuguese | CAB Abstracts | ID: covidwho-1319982

ABSTRACT

Objective: The overactivated immune system due to COVID-19 may be responsible for most of its physiological manifestations, including the neurological ones.

14.
Revista Cientifica Hermes ; 29:3-17, 2021.
Article in Portuguese | Web of Science | ID: covidwho-1289645

ABSTRACT

The pandemic caused by Covid-19 imposed challenges in the continuity of the training itineraries without face-to-face classes. In the investigation, there are existing resources that can instrumentalize remote education, as well as its limits, in courses on the information and communication axis of a technical school. A descriptive-exploratory quantitative, research was used, with data analysis by means of non-parametric statistics, having as data collection the indications in a questionnaire filled out by teachers and students. The results demonstrate the need for continuing teacher training on the use of resources in remote education and attention to the unfavorable environmental conditions of students in participating / carrying out educational activities at home.

15.
Pediatrics ; 147(3):716-717, 2021.
Article in English | EMBASE | ID: covidwho-1177787

ABSTRACT

Purpose: Comprehensive fetal care centers address congenital anomalies by first performing advanced fetal imaging (e.g. ultrasound, echocardiography, fetal magnetic resonance imaging (MRI)) and later discussing those findings, the prognosis, pregnancy management, need for fetal intervention, delivery plan and postnatal management in a multi-disciplinary format. This team approach to counseling can be logistically challenging due to the difficulty in assembling multiple providers from varied specialties on short notice. To reduce exposure during the COVID-19 pandemic, the Centers for Medicare & Medicaid Services (CMS) broadened access to telehealth services. We assessed provider satisfaction with the rapid transition from in-person prenatal visits to multidisciplinary consultations via telehealth as an adaptive response to the pandemic. Methods: Patients who were referred to a busy fetal care center during the first six weeks of the pandemic were connected to the appropriate pediatric subspecialists by videoconference. Some patients underwent advanced fetal imaging and a telehealth consultation with radiology and other appropriate subspecialists took place immediately after imaging was complete. In other instances, imaging occurred and a telehealth visit with all applicable subspecialties took place in the patient's home at a later time. During multidisciplinary meetings, the images were reviewed with all participants via screen sharing. In some cases, providers met to review images prior to admitting the patient to the video call. Provider type is listed in Table 1. Provider satisfaction with the telehealth paradigm was assessed by convenience sampling using an electronic survey. Results: 22 surveys were administered and 18 providers responded for a response rate of 82%. Table 2 shows the overall satisfaction with connectivity and with the format compared to in-person visits. 89% of providers were highly satisfied with the telehealth format. 72% of providers would prefer the multidisciplinary telehealth format to an in-person visit for future visits after COVID-19 restrictions are lifted. 22% of providers would leave the choice to the patient's family. One provider preferred in-person visits. Other providers stated that they find inperson visits better for comforting the patient and for the ability to draw pictures or show educational materials. Conclusion: Providers were overwhelmingly in support of multidisciplinary telehealth conferences for prenatal consultations. This study shows that a multidisciplinary telehealth visit can be done with a high degree of satisfaction for providers. Specific benefits included the ability to review images together as a team, to review the delivery plan and to provide care coordination across specialties. Further studies are needed to better analyze the multidisciplinary approach to telehealth visits for prenatal care.

16.
Genetics and Molecular Biology ; 44(1):21, 2021.
Article in English | Web of Science | ID: covidwho-1154130

ABSTRACT

Components of the complement system and atypical parameters of coagulation were reported in COVID-19 patients, as well as the exacerbation of the inflammation and coagulation activity. Mannose binding lectin (MBL)- associated serine proteases (MASPs) play an important role in viral recognition and subsequent activation of the lectin pathway of the complement system and blood coagulation, connecting both processes. Genetic variants of MASP1 and MASP2 genes are further associated with different levels and functional efficiency of their encoded proteins, modulating susceptibility and severity to diseases. Our review highlights the possible role of MASPs in SARS-COV-2 binding and activation of the lectin pathway and blood coagulation cascades, as well as their associations with comorbidities of COVID-19. MASP-1 and/or MASP-2 present an increased expression in patients with COVID-19 risk factors: diabetes, arterial hypertension and cardiovascular disease, chronic kidney disease, chronic obstructive pulmonary disease, and cerebrovascular disease. Based also on the positive results of COVID-19 patients with anti-MASP-2 antibody, we propose the use of MASPs as a possible biomarker of the progression of COVID-19 and the investigation of new treatment strategies taking into consideration the dual role of MASPs, including MASP inhibitors as promising therapeutic targets against COVID-19.

17.
Genetics & Molecular Biology ; 44(1 Suppl 1):e20200199, 2021.
Article in English | MEDLINE | ID: covidwho-1138619

ABSTRACT

Components of the complement system and atypical parameters of coagulation were reported in COVID-19 patients, as well as the exacerbation of the inflammation and coagulation activity. Mannose binding lectin (MBL)- associated serine proteases (MASPs) play an important role in viral recognition and subsequent activation of the lectin pathway of the complement system and blood coagulation, connecting both processes. Genetic variants of MASP1 and MASP2 genes are further associated with different levels and functional efficiency of their encoded proteins, modulating susceptibility and severity to diseases. Our review highlights the possible role of MASPs in SARS-COV-2 binding and activation of the lectin pathway and blood coagulation cascades, as well as their associations with comorbidities of COVID-19. MASP-1 and/or MASP-2 present an increased expression in patients with COVID-19 risk factors: diabetes, arterial hypertension and cardiovascular disease, chronic kidney disease, chronic obstructive pulmonary disease, and cerebrovascular disease. Based also on the positive results of COVID-19 patients with anti-MASP-2 antibody, we propose the use of MASPs as a possible biomarker of the progression of COVID-19 and the investigation of new treatment strategies taking into consideration the dual role of MASPs, including MASP inhibitors as promising therapeutic targets against COVID-19.

19.
Lat. American Robot. Symp., Braz. Symp. Robot. Workshop Robot. Educ., LARS-SBR-WRE ; 2020.
Article in English | Scopus | ID: covidwho-1069357

ABSTRACT

We draw complete efforts towards the development of a double hybrid tailsitter UAV system, which is basically composed of a multirotor with 2 electric powertrain sets and a flying wing with combustion powertrain set. Our goal is to design a UAV that diminishes consumption for vertically taking off and landing and to perform the horizontal flight with greatest possible autonomy on flight time and distance. Considering these requirements, the UAV is conceptualized and built as a flying wing propelled by a pusher configuration powerplant, with combustion engine propeller, a multi-engine composed of two powerplant sets with electric motors and propellers, positioned on the leading edge of the wing, and two standard elevation control surfaces and two vertical stabilizers that also have the support function for takeoff and landing. Several takeoff, flight, and transition tests were carried out successfully, but autonomy (time and distance) tests due to the COVID19 pandemic. Results show versatility of the hybrid tailsitter for operations in the flight field, in a limited location. The built prototype has proven to be functional and the hybrid system effective, to date. © 2020 IEEE.

20.
Mundo Amazonico ; 11(2):211-222, 2020.
Article in Portuguese | Web of Science | ID: covidwho-1005159

ABSTRACT

This paper aims to provide an overview of Covid-19 in the Yanomami Indigenous Land (TIY), drawing a parallel between the regions of the upper Marauia river (AM), upper Rio Negro (AM) and the Ajarani and Apiau river valley (RR). To place the pandemic of the new coronavirus in the Yanomami context, we start from the notion of xawara - smoke from the epidemic related to contact with non-indigenous people. This essay also aims to analize the access to health and native strategies to fight epidemics.

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