Showing papers by "Vandana Gupta published in 2020"

Phytochemicals as Antiviral Agents: Recent Updates

Abstract: The epidemic of viral diseases is a global concern, mandating an urgent need of most promising antivirals. Some of the viral diseases can be cured by approved antiviral drugs, but for others still do not have any vaccines or drugs available. Most of the approved antiviral drugs are somehow directly or indirectly associated with side effects, which eventually raise the need for the development of antivirals based on natural phytochemicals. Globally, the development of antivirals is shifting towards the plant-derived products as they are less toxic and has less chance to develop resistance. Phytochemicals have been exploited traditionally for the cure of many diseases, and also have been reported to inhibit viral replication/transcription. Most of them inhibit the viruses either during the viral entry inside the host cell or during their replication. Moreover, 50% of the drugs derived from plants are being used in the Western nations. Plants have a variety of phytochemicals like flavonoids, terpenoids, lignins, alkaloids, and coumarins that are having antioxidant activity, and help to inhibit viral genome. Various plant-derived products have been well studied against viruses like herpes virus, human immunodeficiency virus (HIV), influenza, and hepatitis virus. More recently, Coronavirus disease (COVID-19) caused by a newly identified coronavirus has become pandemic, and affected world’s population severely. However, there are still less explored phytochemicals for the inhibition of viruses like dengue virus, chikungunya virus, and other alphaviruses. In this chapter, we will emphasize on the reported phytochemicals and their derivatives, having antiviral properties and their mechanism to treat viral diseases.

Novel Recessive TNNT1 Congenital Core-Rod Myopathy in French Canadians.

Abstract: Objective Recessive null variants of the slow skeletal muscle troponin T1 (TNNT1) gene are a rare cause of nemaline myopathy that is fatal in infancy due to respiratory insufficiency. Muscle biopsy shows rods and fiber type disproportion. We report on 4 French Canadians with a novel form of recessive congenital TNNT1 core-rod myopathy. Methods Patients underwent full clinical characterization, lower limb magnetic resonance imaging (MRI), muscle biopsy, and genetic testing. A zebrafish loss-of-function model using morpholinos was created to assess the pathogenicity of the identified variant. Wild-type or mutated human TNNT1 mRNAs were coinjected with morpholinos to assess their abilities to rescue the morphant phenotype. Results Three adults and 1 child shared a novel missense homozygous variant in the TNNT1 gene (NM_003283.6: c.287T > C; p.Leu96Pro). They developed from childhood very slowly progressive limb-girdle weakness with rigid spine and disabling contractures. They suffered from restrictive lung disease requiring noninvasive mechanical ventilation in 3 patients, as well as recurrent episodes of rhabdomyolysis triggered by infections, which were relieved by dantrolene in 1 patient. Older patients remained ambulatory into their 60s. MRI of the leg muscles showed fibrofatty infiltration predominating in the posterior thigh and the deep posterior leg compartments. Muscle biopsies showed multiminicores and lobulated fibers, rods in half the patients, and no fiber type disproportion. Wild-type TNNT1 mRNA rescued the zebrafish morphants, but mutant transcripts failed to do so. Interpretation This study expands the phenotypic spectrum of TNNT1 myopathy and provides functional evidence for the pathogenicity of the newly identified missense mutation. ANN NEUROL 2020;87:568-583.

A Bayesian game model and network availability model for small cells under denial of service (DoS) attack in 5G wireless communication network

Abstract: Nowadays small cells have become the integral part of 5G wireless communication network (WCN). However, the incorporation of small cells in 5G WCN creates chances for attackers to intrude into the network and this makes the network highly susceptible to attacks. Among various possible attacks, denial of service (DoS) attack is one of the most common network security attacks, and hence in this paper we consider a bandwidth spoofing attack which is a type of DoS attack that is carried out by an attacker during the communication between a macro base station and a small cell base station in a 5G WCN. We then propose a Bayesian game model to capture the interactions between the attacker and the network defender under the bandwidth spoofing attack and obtain the best strategies for defending the DoS attack. Further, since the DoS attack entails unavailability of the network, we address this issue by developing an availability model of the 5G WCN based on a stochastic reward net. Numerical results are presented which give insights into how the availability is affected by the DoS attack. The proposed model is also validated via simulation.

Heterologous Protection to COVID-19 with BCG Vaccine: Deciphering the Reality Using Meta-Analysis Approach

Abstract: The coronavirus disease (COVID-19) emerged in China in December 2019 and has since spread to over 188 countries affecting millions of individuals. Several reports in favour or against the heterologous protection conferred by the BCG vaccine against COVID-19 came up in the initial days of the pandemic and continue to do so. In this study, we compared the three worst-affected nations: The USA, India, and Brazil, their current pandemic scenario, and their respective national BCG immunization policies. USA recommends BCG vaccine only to a specific group of people and never had a national immunization scheme in place. Meanwhile, India introduced a nationwide scheme as early as 1948 and continues to endorse BCG immunization at birth. Brazil used the oral route to administer the BCG vaccine till 1976, and then shifted to intradermal injection. The correlation coefficient for the total number of cases, cases per million, the total number of deaths, deaths per million and case fatality rate ranges between any two countries under study. This indicates a very strong positive correlation in the various epidemiological parameters between countries with no national immunization scheme (USA) and countries with stringent national policies on BCG vaccination. The strongest correlation exists between the USA and Brazil followed by Brazil and India which is very closely followed by the USA and India. We found no consistent evidence to infer in favour of the hypothesis that BCG provides any non-specific protection against COVID-19. Heterologous Protection to COVID-19 with BCG Vaccine: Deciphering the Reality Using Meta-Analysis Approach