Evaluation of C4b as an adjunct marker in symptomatic RT-PCR negative Covid-19 cases

IntroductionDetecting low viral load has been a challenge in this pandemic, which has led to its escalated transmission. Complement activation has been implicated in pathogenesis of Covid-19 infection. Thus, evaluation of complement activation in suspected Covid-19 infection may help to detect infection and limit false negative cases thus limiting transmission of infection. We speculate that measuring C4b, produced from an activated complement system due to the presence of Covid-19 may help in its detection, even when the viral titers are low.MethodsPlasma C4b levels of symptomatic RT-PCR positive patients (cases, n = 40); symptomatic RT-PCR negative patients (n = 35) and asymptomatic RT-PCR negative controls (n = 40) were evaluated. Plasma C5b-9, IL-6, D-dimer and C1-Inhibitor (C1-INH) were also measured in cases and controls. ELISA kits were used for all measurements. Statistical analyses were carried out using Stata, version 12 (Stata Corp., Texas, USA).ResultsC4b levels were found to be significantly increased in RT-PCR positive patients as compared to asymptomatic RT-PCR negative controls. RT-PCR negative but symptomatic patients still showed increased C4b levels. The significantly higher levels of C4b in cases with a cut-off value of ≥ 116 ng/ml with optimum sensitivity and specificity of 80% and 52% respectively is indicative of its possible use as an adjunct marker. Increased levels of D-dimer, IL6, along with decreased levels of C1-INH were found in cases compared to controls. Whereas, C5b-9 levels were not significantly raised in cases.ConclusionsThe results of our study suggests that plasma C4b may help to detect infection in false negative cases of RT-PCR that escape detection owing to low viral load. However, to confirm it a large-scale study is needed.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12291-022-01033-z.     

How Many Ways Can We Define Online Learning? A Systematic Literature Review of Definitions of Online Learning (1988-2018)

ABSTRACT

Online learning as a concept and as a keyword has consistently been a focus of education research for over two decades. In this paper, we present results from a systematic literature review for the definitions of online learning because the concept of online learning, though often defined, has a range of meanings attached to it. Authors and scholars use the term to mean very distinct, if not contradictory concepts. We conducted systematic literature for over the last 30 years (1988 to 2018) to investigate the number and content of definitions of online learning. We collected 46 definitions from 37 resources and conducted a content analysis on these sets of definitions. Content analysis of the collected definitions led to an understanding of the core elements for defining online learning, the confusion surrounding the terms and the synonyms used for online learning. An evolution of the definition of the concept of online learning was also mapped to the evolution of technology in the last three decades.     

How to Teach and to Ensure a Good,Sound Religious Education through a Multi‐faith Approach at the Primary School Level

If Religious Education is to have an effective place in education and is not objectionable to younger pupils, there would appear to be a case for laying a foundation of knowledge, while the attitude to the subject is favourable and learning is thus easier to achieve. Then pupils are more likely to be in a well‐informed position to discuss religion at the top of the school, than if teaching has already begun at an age when, although they were intellectually ready and able to undertake open debate, prejudice had already closed teenagers’ eyes to the whole matter (Attfield, 1974)

The school should be a community within which children should learn to live the ‘good life’... By example at first hand children can learn to love and care for others, to be generous, kind and courageous. Good experiences in personal relationships in early life will make a most important contribution to an understanding of spiritual and moral values when children are older. (The Plowden Report, 1967, Vol. 1, p. 206, para. 568)     

Quality Assurance in Open and Distance, Education： a Case Study of Kota Open University

After a brief analysis of the concept of quality in open and distance education, information technology for quality assurance and Indian initiative for quality improvement, the paper examines the quality assurance measures at Kota Open University under the following areas ： planning academic programmes ; developing academic programmes ; producing learning materials ; implementing programmes ; reviewing courses/programmes ; and ing human resources.     

Alteration in some antioxidant enzymes in cardiac tissue upon monosodium glutamate [MSG] administration to adult male mice

4mg and 8mg monosodium glutamate per gram body weight was administered subcutaneously for 6 consecutive days to normal adult male mice and its effect was seen on 31^st day after the last injection on some antioxidant enzymes in heart. A significant dose dependent increase in lipid peroxidation and xanthine oxidase level was observed, whereas the activity of free radical scavenging enzymes such as superoxide dismutase and catalase was decreased in both monosodium glutamate treated groups (Group-2 and Group-3). So, the present work suggested that monosodium glutamate at dose level of 4mg/g body weight and above induced oxidative stress in the cardiac tissue by changing the activity of free radical initiating enzyme such as xanthine oxidase and scavenging enzymes like superoxide dismutase and catalase.     

Assessment of renal acidification capacity of stone formers by acid challenge test

Acid challenge test was carried out on 87 subjects (37 normal and 50 radiologically proven stone formers) to assess their renal acidification capacity. NS were given three doses viz. 75, 100 and 150 mg NH₄Cl/Kg body weight while the SF were tested with only 150 mg dose which was found to be an adequate dose. Ammonium chloride was given in gelatin capsules with breakfast and hourly urine samples were collected for next 7 hours. pH, creatinine, calcium, inorganic phosphorus, citrate, titrable acid and ammonium were analysed in all the samples. The incidence of renal tubular acidosis (RTA) in NS, tested with 75 mg and 100 mg/kg doses of ammonium chloride, was 50% and 10% respectively while it was nil and 24% respectively in NS and SF tested with 150mg/kg dose. Complete RTA was detected in one SF. No significant difference was observed in urinary profile of NS and SF except that the hourly titrable acid excretion was lower in later. A comparison between with and without RTA SF revealed that titrable acid and phosphate excretion decreased in RTA defect. Overall data indicate that (a) RTA was an etiologic factor in one fourth of the SF; (b) an oral acid challenge test is a good adjunct to detect this condition and (c) acid challenge increases calcium, phosphate and titrable acid excretion and decreases citrate.     

Oxidative stress and antioxidant status in patients with chronic myeloid leukemia

Chronic myeloid leukemia is a myeloproliferative disorder with a unique rearrangement, the Philadelphia chromosome. Oxidative stress, a pervasive condition of an increased number of reactive oxygen species, is now recognized to be prominent feature of various diseases and their progression. Thus antioxidants, which control the oxidative stress state, represent a major line of defense regulating overall true state of health. The relationship between antioxidants status and levels of well-known markers of oxidative stress that are measured as lipid peroxides and oxidized proteins reflect better health indices and postures. The aim of this study was to evaluate the role of oxidative stress in pathophysiology of Chronic myeloid leukemia by measuring the circulating plasma lipid peroxide levels in terms of malonyldialdehyde, total lipid hydroperoxide and oxidized proteins as protein carbonyl whereas antioxidant status were estimated in terms of reduced glutathione and total thiol in plasma of Chronic myeloid leukemia patients. The present study included 47 Chronic myeloid leukemia patients and 20 age-and sex-matched healthy subjects. Out of 47 Chronic myeloid leukemia patients, 31 were in chronic phase (CML-CP) and 16 in accelerated phase (CML-AP). The median age of Chronic myeloid leukemia patients was 33 years and that of controls was 32 years. Oxidative stress and antioxidant status in plasma were evaluated by spectrophotometric procedures. There was a significant increase (p<0.05) in plasma malonyldialdehyde, total lipid hydroperoxide and protein carbonyl levels in Chronic myeloid leukemia patients as compared to healthy subjects. Our results also showed that plasma malonyldialdehyde and protein carbonyl levels were markedly elevated (p<0.05) in both chronic phase (CML-CP) and accelerated phase (CML-AP) as compared to healthy volunteers. Antioxidant status was found to be significantly decreased (p<0.05) in Chronic myeloid leukemia patients and its phases as compared to healthy participants. It could be concluded that oxidative stress may be associated with the pathophysiology of Chronic myeloid leukemia.