Advancements in COVID- 19 Testing: An in-depth overview

Abstract:

COVID-19 rapidly evolved as a pandemic, killing and hospitalising millions of people, creating unprecedented hurdles for communities and health care systems worldwide. The rapidly evolving pandemic prompted the head of the World Health Organisation to deliver a critical message: "test, test, test." The response from the diagnostic industry and researchers worldwide was overwhelming, resulting in more than a thousand commercial tests available in the market worldwide. Several sampling approaches and diagnostic techniques have been employed from the early stages of the pandemic, such as SARS-CoV-2 detection by targeting the viral RNA or protein, indirectly via antibody testing, biochemical estimation, and various imaging techniques, and many are still in the various stages of development and yet to be marketed. Accurate testing techniques and appropriate sampling are the need of the hour to manage, diagnose and treat the pandemic, especially in the current crisis, where SARS-CoV-2 undergoes constant mutation, evolving into various strains, which are pretty challenging. The article discusses various testing techniques as well as screening methods for detection, treatment, and management of COVID-19 transmission, such as NAAT, PCR, isothermal detection including RT-LAMP, RPA, NASBA, RCA, SDA, NEAR, and TMA, CRISPR strategy, nanotechnology approach, metagenomic profiling, point of care tests, virus neutralization test, ELISA, biomarker estimation, utilization of imaging techniques such as CT, ultrasonography, brain MRI in COVID-19 complications, and other novel strategies including microarray methods, microfluidic methods and artificial intelligence with an emphasis on advancements in the testing strategies for the diagnosis, management, and prevention of COVID-19.

The Role of Mitochondrial Genes in Neurodegenerative Disorders

Mitochondrial disorders are clinically heterogeneous, resulting from nuclear gene and mitochondrial mutations that disturb the mitochondrial functions and dynamics. There is a lack of evidence linking mtDNA mutations to neurodegenerative disorders, mainly due to the absence of noticeable neuropathological lesions in postmortem samples. This review describes various gene mutations in Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, multiple sclerosis, and stroke. These abnormalities, including PINK1, Parkin, and SOD1 mutations, seem to reveal mitochondrial dysfunctions due to either mtDNA mutation or deletion, the mechanism of which remains unclear in depth.

Laparoscopic percutaneous internal ring suturing for paediatric inguinal hernias: a South African tertiary centre experience

BACKGROUND

Laparoscopic inguinal hernia repair is routine in many paediatric centres. One of several techniques described in 2006 is the laparoscopic percutaneous internal ring suturing (PIRS) technique. This technique which is not widely used in South Africa has been adopted for paediatric inguinal hernias at our institution, and this is a review of the experience.

METHOD

The study is a retrospective review of the patients who underwent PIRS (a single port combined percutaneous procedure used to close the internal ring) at our hospital from October 2018 until March 2020. We describe the technique in our setting and review our cohort of patients, demographics, clinical presentation, operative duration and complications.

RESULTS

One hundred and ten laparoscopic PIRS procedures were performed on 94 patients; 15 had bilateral inguinal hernias. Polydioxanone and Prolene were the sutures used for the procedures. Average operative time was 12 minutes for unilateral hernias and 33 minutes for bilateral hernias. All operations were completed laparoscopically. Follow-up was for a minimum of three months, but up to 21 months. Complications included three intraoperative haematomas, three hydrocoeles and two umbilical granulomas postoperatively. There were two recurrent hernias of which one was managed with redo PIRS; the other required open herniotomy for an irreducible obstructed hernia.

CONCLUSION

This review is supportive evidence that the PIRS technique for managing paediatric inguinal hernias in a tertiary institution in South Africa can be performed safely with few complications.

Current perspective of COVID-19 on neurology: A mechanistic insight

SARS-CoV-2, the novel coronavirus and the causative organism of Covid-19 pandemic wreaked havoc worldwide producing asymptomatic to symptomatic cases leading to significant morbidity and mortality even after infection. Most of the countries reported a mortality rate of 2-3 % majorly due to cardiorespiratory failures. Recent studies highlighted the neurological involvement playing a key role in cardiorespiratory failures and other symptoms such as headache, anosmia, and ageusia observed in Covid-19 patients. Studies suggests SARS-CoV-2 entry via olfactory epithelium (OE) and the expression of type 2 transmembrane serine protease (TMPRSS2) in addition to angiotensin converting enzyme 2 (ACE2) can facilitate SARS-CoV-2 neurotropism. The virus can either travel via peripheral blood vessel causing endothelial dysfunction, triggering coagulation cascade and multiple organ dysfunction or reach the systemic circulation and take a different route to the blood brain barrier (BBB), disrupting the BBB causing neuroinflammation or neuronal excitotoxicity resulting in the development of encephalitis, encephalopathy, seizures, and strokes. SARS-CoV-2 invasion on brain stem is believed to be responsible for the cardiorespiratory failures observed in Covid-19 patients. Apart from viral invasion via hematogenous route, SARS-CoV-2 neural invasion via PNS nerve terminal, resulting in viral replication and retrograde transportation to soma leading to invasion of the CNS including the brain producing neurological manifestations of the disease either in the initial stages or during the course of the disease and even in a long period post infection in many cases. The ACE2 receptors are expressed in the brain and glial cells and SARS-CoV-2 acts via neuronal as well as non-neuronal pathway. But the exact cell types involved and how they can trigger inflammatory pathways need further in-depth study for the development of targeted therapy.

A Comprehensive Overview of Colon Cancer- A Grim Reaper of the 21st Century

A few decades ago, the incidence of colorectal cancer (CRC) was low and is now the fourth in the list of deadly cancers producing nearly a million deaths annually. A population that is aging along with risk factors such as smoking, obesity, sedentary lifestyle with little or no physical activity, and non-healthy food habits of developed countries can increase the risk of colorectal cancer. The balance in gut microbiota and the metabolites produced during bacterial fermentation within the host plays a significant role in regulating intestinal diseases as well as colorectal cancer development. Recent progress in the understanding of illness resulted in multiple treatment options such as surgery, radiation, and chemotherapy, including targeted therapy and multitherapies. The treatment plan for CRC depends on the location, stage and grade of cancer as well as genomic biomarker tests. Despite all the advancements made in the genetic and molecular aspects of the disease, the knowledge seems inadequate as the drug action as well as the wide variation in drug response did not appear strongly correlated with the individual molecular and genetic characteristics, which suggests the requirement of comprehensive molecular understanding of this complex heterogeneous disease. Furthermore, multitherapies or a broad spectrum approach, which is an amalgamation of the various promising as well as effective therapeutic strategies that can tackle heterogeneity and act on several targets of the disease, need to be validated in clinical studies. The latest treatment options have significantly increased the survival of up to three years in the case of advanced disease. The fact that colorectal cancer is developed from a polypoid precursor, as well as the symptoms of the disease that occur at an advanced stage, underlines how screening programs can help early detection and decrease mortality as well as morbidity from CRC.

The Chronicle of COVID-19 and Possible Strategies to Curb the Pandemic

COVID-19, a type of infection that emerged in Wuhan, has become a pandemic affecting people worldwide and is rapidly spreading and evolving. Day by day, the confirmed cases and deaths are increasing many folds. SARS-CoV-2 is a novel virus; therefore, limited data are available to curb the disease. Epidemiological approaches, such as isolation, quarantine, social distancing, lockdown, and curfew, are being employed to halt the spread of the disease. Individual and joint efforts all over the world are producing a wealth of data and information which are expected to produce therapeutic strategies against COVID-19. Current research focuses on the utilization of antiviral drugs, repurposing strategies, vaccine development, as well as basic to advanced research about the organism and the infection. The review focuses on its life cycle, targets, and possible therapeutic strategies, which can lead to further research and development of COVID-19 therapy.

COVID-19 and Domestic Animals: Exploring the Species Barrier Crossing, Zoonotic and Reverse Zoonotic Transmission of SARS-CoV-2

BACKGROUND

To date, more than thirty animals have been tested positive for SARS-CoV-2; all of them infected by humans with COVID-19. Some animal experiments suggested the possibility of animal to animal transmission of SARS-CoV-2 that was seen in some cases of infected animals. Animal to human transmission was considered unlikely until investigations revealed the possibility of mink to human transmission of SARS-CoV-2 in the Netherlands.

OBJECTIVE

The current study aims at highlighting the predominance of SARS-CoV-2 infection in various animal species, reverse zoonotic transmission and proposing possible animal models that might aid in the study and development of a vaccine against Covid-19.

METHODS

The authors have gathered information on various animal species infected with SARS-CoV-2 and possible tests conducted via online news reports, websites and Scopus indexed journals.

RESULTS

The study of the susceptibility of SARS-CoV-2 to domestic animals concluded that pigs, chicken, and ducks were not vulnerable to Covid-19; dogs showed less susceptibility to SARS-CoV-2 and cats as well as ferrets were seen susceptible to Covid-19. SARS-CoV-2 has been seen crossing the species barrier, infecting humans from the wild with the yet unclear source, spreading from humans to humans quickly, humans to animals, animals to animals, and is likely to spread from animals to humans even though minimally. Animals appear somewhat resistant to SARS-CoV-2 transmission compared to humans who globally crossed eight million infection cases, and the infected animals mostly do not show many complications and recover quickly.

CONCLUSION

Precautions are advised to prevent human to animal transmission of the virus, and in some areas, to avoid animal to human spread of the virus. Further monitoring is required to assess the SARS-CoV-2 infection in animals as COVID-19 is a rapidly evolving condition worldwide. Cats and ferrets have physiological resemblance and genome sequencing studies propose the possibility of these species to be used as animal models for investigating the SARS-CoV-2 infection and this might aid in further studies and vaccine development against Covid-19.

An Agathokakological Tale of Δ9-THC: Exploration of Possible Biological Targets

Δ⁹-Tetrahydrocannabinol (Δ⁹-THC), the active phytocannabinoid in cannabis, is virtually an adjunct to the endogenous endocannabinoid signaling system. By interacting with G-proteincoupled receptors CB1 and CB2, Δ⁹-THC affects peripheral and central circulation by lowering sympathetic activity, altering gene expression, cell proliferation, and differentiation, decreasing leukocyte migration, modulating neurotransmitter release, thereby modulating cardiovascular functioning, tumorigenesis, immune responses, behavioral and locomotory activities. Δ⁹-THC effectively suppresses chemotherapy-induced vomiting, retards malignant tumor growth, inhibits metastasis, and promotes apoptosis. Other mechanisms involved are targeting cell cycle at the G2-M phase in human breast cancer, downregulation of E2F transcription factor 1 (E2F1) in human glioblastoma multiforme, and stimulation of ER stress-induced autophagy. Δ⁹-THC also plays a role in ameliorating neuroinflammation, excitotoxicity, neuroplasticity, trauma, and stroke and is associated with reliving childhood epilepsy, brain trauma, and neurodegenerative diseases. Δ⁹-THC via CB1 receptors affects nociception, emotion, memory, and reduces neuronal excitability and excitotoxicity in epilepsy. It also increases renal blood flow, reduces intraocular pressure via a sympathetic pathway, and modulates hormonal release, thereby decreasing the reproductive function and increasing glucose metabolism. Versatile medical marijuana has stimulated abundant research demonstrating substantial therapeutic promise, suggesting the possibilities of first-in-class drugs in diverse therapeutic segments. This review represents the current pharmacological status of the phytocannabinoid, Δ⁹-THC, and synthetic analogs in cancer, cardiovascular, and neurodegenerative disorders.

Fascinating Chemopreventive Story of Wogonin: A Chance to Hit on the Head in Cancer Treatment

Cancer, global havoc, is a group of debilitating diseases that strikes family as well as society. Cancer cases are drastically increasing these days. Despite many therapies and surgical procedures available, cancer is still difficult to control due to limited effective therapies or targeted therapies. Natural products can produce lesser side effects to the normal cells, which are the major demerit of chemotherapies and radiation. Wogonin, a natural product extracted from the plant, Scutellaria baicalensis has been widely studied and found with a high caliber to tackle most of the cancers via several mechanisms that include intrinsic as well as extrinsic apoptosis signaling pathways, carcinogenesis diminution, telomerase activity inhibition, metastasis inhibition in the inflammatory microenvironment, anti-angiogenesis, cell growth inhibition and arrest of the cell cycle, increased generation of H₂O₂ and accumulation of Ca²⁺ and also as an adjuvant along with anticancer drugs. This article discusses the role of wogonin in various cancers, its synergism with various drugs, and the mechanism by which wogonin controls tumor growth.

Laparoscopic percutaneous internal ring suturing for paediatric inguinal hernias: a South African tertiary centre experience

ABSTRACT BACKGROUND: Laparoscopic inguinal hernia repair is routine in many paediatric centres. One of several techniques described in 2006 is the laparoscopic percutaneous internal ring suturing (PIRS) technique. This technique which is not widely used in South Africa has been adopted for paediatric inguinal hernias at our institution, and this is a review of the experience METHOD: The study is a retrospective review of the patients who underwent PIRS (a single port combined percutaneous procedure used to close the internal ring) at our hospital from October 2018 until March 2020. We describe the technique in our setting and review our cohort of patients, demographics, clinical presentation, operative duration and complications RESULTS: One hundred and ten laparoscopic PIRS procedures were performed on 94 patients; 15 had bilateral inguinal hernias. Polydioxanone and Prolene were the sutures used for the procedures. Average operative time was 12 minutes for unilateral hernias and 33 minutes for bilateral hernias. All operations were completed laparoscopically. Follow-up was for a minimum of three months, but up to 21 months. Complications included three intraoperative haematomas, three hydrocoeles and two umbilical granulomas postoperatively. There were two recurrent hernias of which one was managed with redo PIRS; the other required open herniotomy for an irreducible obstructed hernia CONCLUSION: This review is supportive evidence that the PIRS technique for managing paediatric inguinal hernias in a tertiary institution in South Africa can be performed safely with few complications Supplementary video available online: http://sajs.redbricklibrary.com/index.php/sajs/article/view/3498 Keywords: inguinal hernia, paediatric, laparoscopy, percutaneous internal ring suturing

Molecular mechanism of zinc neurotoxicity in Alzheimer's disease

Zinc (Zn) is an essential trace element for most organisms, including human beings. It plays a crucial role in several physiological processes such as catalytic reaction of enzymes, cellular growth, differentiation and metabolism, intracellular signaling, and modulation of nucleic acid structure. Zn containing above 50 metalloenzymes is responsible for proteins, receptors, and hormones synthesis and has a critical role in neurodevelopment. Zn also regulates excitatory and inhibitory neurotransmitters such as glutamate and GABA and is found in high concentration in the synaptic terminals of hippocampal mossy fibers that maintains cognitive function. It regulates LTP and LTD by regulation of AMPA and NMDA receptors. But an excess or deficiency of Zn becomes neurotoxic or cause impairment in growth or sexual maturation. There is mounting evidence that supports this idea of Zn becoming neurotoxic and being involved in the pathogenesis of AD. Zn dyshomeostasis in AD is an area that needs attention as moderate concentration of Zn is involved in the memory regulation via regulation of amyloid plaque. Dyshomeostasis of Zn is involved in the pathogenesis of diseases like AD, ALS, depression, PD, and schizophrenia.

Magnetic nanoparticles for hyperthermia in cancer treatment: an emerging tool

Cancer remains as the major cause of death worldwide. The main reason why available therapies fail is that a vicious cycle in established which initiates multiple pathways and recurrence after metastasis. Hyperthermic treatment, which involves heating tumor tissues to a moderate temperature of 40-43 °C, has emerged as an effective strategy for treating tumors. This method is highly efficient at destroying tumor cells and does not induce the side effects of conventional cancer treatments. On the other hand, hyperthermic treatment method can be co-administered with conventional treatments. Nanotechnology had created huge opportunities in almost all areas of research, including the field of hyperthermic treatment. The utilization of magnetic nanoparticles (MNPs) offers functionalities not possible using conventional magnetic materials. In this review, we detail recent developments and applications of MNPs for hyperthermic treatment and discuss future possibilities.

Exploring the new horizons of drug repurposing: A vital tool for turning hard work into smart work

Drug discovery and development are long and financially taxing processes. On an average it takes 12-15 years and costs 1.2 billion USD for successful drug discovery and approval for clinical use. Many lead molecules are not developed further and their potential is not tapped to the fullest due to lack of resources or time constraints. In order for a drug to be approved by FDA for clinical use, it must have excellent therapeutic potential in the desired area of target with minimal toxicities as supported by both pre-clinical and clinical studies. The targeted clinical evaluations fail to explore other potential therapeutic applications of the candidate drug. Drug repurposing or repositioning is a fast and relatively cheap alternative to the lengthy and expensive de novo drug discovery and development. Drug repositioning utilizes the already available clinical trials data for toxicity and adverse effects, at the same time explores the drug's therapeutic potential for a different disease. This review addresses recent developments and future scope of drug repositioning strategy.

Advancements in nanotherapeutics for Alzheimer’s disease: current perspectives

Objectives

Considerable progress has been made in the treatment of Alzheimer’s disease (AD), but all available strategies focus on alleviating symptoms rather than curing, which means that AD is viewed as an unresolvable neurodegenerative disease. Nanotechnological applications offer an alternative platform for the treatment of neurodegenerative diseases. This review aims to summarize the recent nanomedicine and nanotechnology developments for the treatment of AD.

Key findings

A plethora of nanocarriers and nanoparticle prodrugs have been reported to have negligible cytotoxicity in animal models, and these developments have revealed new opportunities for development of new classes of potent drug formulations for AD. Different nanotechnology-based approaches such as polymers, emulsions, lipo-carriers, solid lipid carriers, carbon nanotubes and metal-based carriers have been developed over the past decade, and they have been focusing on both neuroprotective and neurogenerative techniques to treat AD. Studies also reveal that nanotechnological approaches can aid in early diagnosis of AD and enhance therapeutic efficacy and bioavailability.

Summary

Notably, the drugs used conventionally to target the central nervous system have limitations that include an inability to cross the ‘blood–brain barrier’ or the ‘blood–cerebrospinal fluid barrier’ effectively and high drug efflux due to the activity of P-glycoprotein, but these limitations can be successfully overcome when nanocarriers are used for targeted drug delivery in AD.