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Author(s):  
Sujal Patel ◽  
Dhruv Talwar ◽  
Sunil Kumar ◽  
Sourya Acharya ◽  
Mansi Patel

Ferritin overload is a frequent problem encountered in patients with beta thalassemia amounting to various complications. One of rare but important complication of ferritin overload is ferritin overload induced toxic encephalopathy. Serum ferritin has been recognised as a important marker of inflammation and cytokine storm in COVID19.We present a case of Long COVID syndrome presenting as toxic encephalopathy in a case of beta thalassemia in spite of the patient being compliant to desferroxamine therapy.This report highlights the synergistic effect of Severe Acute Respiratory Syndrome Coronavirus. 2(SARS CoV 2) mediated neuroinflammation through direct viral invasion and the release of inflammatory cytokines including ferritin  resulting in toxic encephalopathy in a beta thalassemia major patient who was already prone to develop hyperferritenemia.Ferritin functions as a pro-inflammatory cytokine and it’s level increases in both thalassemia and COVID-19 and the index case presented here had both the conditions predisoposing him to develop toxic encephalopathy even after being compliant to deferoxamine therapy. It is important to recognise and treat this condition in order to prevent mortality and morbidity in patients of beta thalassemia who contract COVID19.


Geofluids ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Tianyi Tan ◽  
Hui Zhang ◽  
Xusheng Ma ◽  
Yufei Chen

Wellbore instability is a frequent problem of shale drilling. Accurate calculation of surge-swab pressures in tripping processes is essential for wellbore pressure management to maintain wellbore stability. However, cutting plugs formed in shale horizontal wells have not been considered in previous surge-swab pressure models. In this paper, a surge-swab pressure model considering the effect of cutting plugs is established for both open pipe string and closed pipe string conditions; In this model, the osmotic pressure of a cutting plug is analyzed. The reduction of cutting plug porosity due to shale hydration expansion and dispersion is considered, ultimately resulting in an impermeable cutting plug. A case study is conducted to analyze swab pressures in a tripping out process. The results show that, in a closed pipe condition, the cutting plug significantly increases the swab pressures below it, which increase with the decrease of cutting plug porosity and the increase of cutting plug length. Under the give condition, the swab pressure at the bottom of the well increases from 3.60 MPa to 8.82 MPa due to the cutting plug, increasing by 244.9%. In an open pipe string condition, the cutting plug affects the flow rate in the pipes and the annulus, resulting in a higher swab pressure above the cutting plug compared to a no-cutting plug annulus. The difference increases with the decrease of the porosity and the increase of the length and the measured depth of the cutting plug. Consequently, the extra surge-swab pressures caused by cutting plugs could result in wellbore pressures out of safety mud density window, whereas are ignored by previous models. The model proposes a more accurate wellbore pressure prediction and guarantees the wellbore stability in shale drilling.


2021 ◽  
Vol 26 (1) ◽  
Author(s):  
Dazhi Fu ◽  
Chunxiao Wang ◽  
Lei Yu ◽  
Rui Yu

Abstract Background Currently, resistance against cisplatin (DDP) is a frequent problem for the success of advanced gastric carcinoma (GC) chemotherapy. Here, we sought to investigate the function of activating transcription factor 3 (ATF3) n GC chemoresistance. Methods Expression of ATF3 was determined in GC cell lines (MNK45, SGC7901, and BGC823) and cisplatin (DDP)-resistant cells (SGC7901/DDP and BGC823/DDP). Biological informatics was performed to analyze ATF3 expression and prognosis in GC patients. Cisplatin resistance was evaluated. Ferroptosis was detected after ATF3 transfection of cells. The underlying molecular mechanism was also investigated. Results Transcripts of ATF3 were decreased in GC cells and GC tissues. Kaplan–Meier plotter analysis revealed that ATF3 expression was positively related to the overall survival of GC patients. In particular, lower levels of ATF3 were observed in cisplatin-resistant SGC7901/DDP and BGC823/DDP relative to their parental cells. Notably, ATF3 elevation sensitized cisplatin-resistant cells to cisplatin. Mechanically, compared with parental cells, SGC7901/DDP and BGC823/DDP cells exhibited lower ferroptosis evident by lower ROS, MDA and lipid peroxidation and higher intracellular GSH levels. However, ATF3 elevated ferroptosis in SGC7901/DDP and BGC823/DDP cells. Intriguingly, ATF3 overexpression together with ferroptosis activator erastin or RSL3 treatment further enhanced ferroptosis and cisplatin resistance; however, the ferroptosis suppressor liproxstatin-1 reversed the function of ATF3 in ferroptosis and cisplatin resistance. Additionally, cisplatin-resistant cells exhibited stronger activation of Nrf2/Keap1/xCT signaling relative to parental cells, which was restrained by ATF3 up-regulation. Importantly, restoring Nrf2 signaling overturned ATF3-mediated ferroptosis and cisplatin resistance. Conclusion ATF3 may sensitize GC cells to cisplatin by induction of ferroptosis via blocking Nrf2/Keap1/xCT signaling, supporting a promising therapeutic approach for overcoming chemoresistance in GC.


2021 ◽  
Vol 1 (2) ◽  
pp. 319-339
Author(s):  
Jean Rosemond Dora ◽  
Karol Nemoga

In this work, we tackle a frequent problem that frequently occurs in the cybersecurity field which is the exploitation of websites by XSS attacks, which are nowadays considered a complicated attack. These types of attacks aim to execute malicious scripts in a web browser of the client by including code in a legitimate web page. A serious matter is when a website accepts the “user-input” option. Attackers can exploit the web application (if vulnerable), and then steal sensitive data (session cookies, passwords, credit cards, etc.) from the server and/or from the client. However, the difficulty of the exploitation varies from website to website. Our focus is on the usage of ontology in cybersecurity against XSS attacks, on the importance of the ontology, and its core meaning for cybersecurity. We explain how a vulnerable website can be exploited, and how different JavaScript payloads can be used to detect vulnerabilities. We also enumerate some tools to use for an efficient analysis. We present detailed reasoning on what can be done to improve the security of a website in order to resist attacks, and we provide supportive examples. Then, we apply an ontology model against XSS attacks to strengthen the protection of a web application. However, we note that the existence of ontology does not improve the security itself, but it has to be properly used and should require a maximum of security layers to be taken into account.


2021 ◽  
Author(s):  
Leila Dos Santos Machado ◽  
Fabiane Dörr ◽  
Felipe Augusto Dörr ◽  
Daniele Frascareli ◽  
Darllene S. Melo ◽  
...  

Abstract Toxic cyanobacteria blooms are a frequent problem in subtropical reservoirs and freshwater systems. The purpose of this study was to investigate the occurrence of potentially toxic cyanobacteria and the environmental conditions associated with the presence of cyanotoxins in a Brazilian subtropical reservoir. Five collections were carried out at seven sampling locations in the reservoir, during the rainy and dry seasons, between the years 2016 and 2017. There was permanent occurrence of Raphidiopsis raciborskii (Woloszynska) Aguilera, Berrendero Gómez, Kastovsky, Echenique & Salerno, ranging between dominant and abundant, with an average biomass of 38.8 ± 29.9 mg L− 1. Also abundant were D. solitarium, D. planctonicum, P. isothrix, and A. gracile. Saxitoxin (STX) was detected in all the collected samples (0.11 ± 0.05 µg L− 1). Microcystin (MC) was also detected, but at lower concentrations (0.01 ± 0.0 µg L− 1). Low availability of NO3− and phosphorus limitation had significant effects on the R. raciborskii biomass and the levels of STX and MC. It was observed that R. raciborskii was sensitive to thermal stratification, at the same time that STX levels were higher. This suggested that STX was produced under conditions that restricted the growth of R. raciborskii. These are important findings, because they add information about the permanent occurrence of STX and R. raciborskii in an aquatic ecosystem limited by phosphorus, vulnerable to climatic variations, and polluted by domestic effluents.


Nutrients ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 1634
Author(s):  
Mauro Sérgio Toporovski ◽  
Mauro Batista de Morais ◽  
Abrão Abuhab ◽  
Mauro Acir Crippa Júnior

Constipation is a frequent problem in children. We evaluated the effect of a mixture (polydextrose [PDX] and fructooligosaccharide [FOS]) in children with constipation. We performed a prospective interventional study with a mixture (PDX 4.17 g and FOS 0.45 g) in a daily dose of food supplement. The intervention lasted 45 days, with visits at 15, 30, and 45 days after administration. The sample comprised 105 patients, of whom 77 completed the intervention. A statistically significant reduction in the frequency of symptoms was observed at the end of the study. The frequency of children with fewer than three bowel movements per week dropped from 59.7% to 11.7%, and there was a decrease in the frequency of Bristol type 1 and 2 dry stools (68.8% to 7.8%), pain on defecation (79.2% to 10.4%), and fear of defecation (68.8% to 3.9%). The proportion of children with abdominal pain symptoms decreased from 84.2% to 2.6% at the end of the study. A relevant limitation of the present study was the lack of a control group treated with placebo. The administration of the PDX/FOS mixture was accompanied by a significant reduction in the frequency of constipation symptoms of the children evaluated. The tolerability was very good, and the rate of adverse effects was low.


Author(s):  
Santosh Kumar ◽  
Nitendra Kumar ◽  
Khursheed Alam

Background: In the image processing area, deblurring and denoising are the most challenging hurdles. The deblurring image by a spatially invariant kernel is a frequent problem in the field of image processing. Methods: For deblurring and denoising, the total variation (TV norm) and nonlinear anisotropic diffusion models are powerful tools. In this paper, nonlinear anisotropic diffusion models for image denoising and deblurring are proposed. The models are developed in the following manner: first multiplying the magnitude of the gradient in the anisotropic diffusion model, and then apply priori smoothness on the solution image by Gaussian smoothing kernel. Results: The finite difference method is used to discretize anisotropic diffusion models with forward-backward diffusivities. Conclusion: The results of the proposed model are given in terms of the improvement.


2021 ◽  
Vol 129 ◽  
pp. 07001
Author(s):  
Jaroslav Belas ◽  
Katarina Zvarikova

Research background: The global situation is alarming. Many scholars, politicians, non-profit organizations and journalists worldwide remind of these arising problems. Sustainability seems to be the only solution, and also many companies try to do their best to contribute to this issue. Purpose of the article: CSR is considered a valuable tool in many fields – profit, stakeholders, and environmental dimensions. All these dimensions are characterized by their specifics, but it is proven that CSR positively impacts all of them. But the frequent problem is that although the companies are aware of the stakeholders´ importance, they are not able to report their activities or report them in an understanding way. Methods: Methods of the literature review is used for the theoretical background to understand the importance of three dimensions of CSR. Method of analysis is used to analyze of GRI index. Findings & Value added: Literature review proves the importance of CSR towards all three dimensions. According to analysis of the DRI index, it is evident, that not only organizations from developed countries have reported, but also organizations from developing countries had become reporting. Following the result of our analysis, we can see that 1 694 organizations from 80 countries try to come close to stakeholders and want to inform them about their activities.


2021 ◽  
Vol 4 (12) ◽  
pp. 105-113
Author(s):  
Gegine H. Harutyunyan ◽  
◽  
Maria A. Vakhrushina ◽  

The article offers a step-by-step algorithm for developing an approach to accounting for reve-nue under a contract with a buyer. The practice of applying IFRS 15 shows that a frequent problem of the correct recognition of revenue may be the lack of a qualitative analysis of the concluded contract and omis-sions of important terms of transactions and requirements of the standard. The step-by-step algorithm pro-posed below structures the requirements of the standard and ensures the correctness of their application without gaps.


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