PM sensors as an indicator of overall air quality: Pre-COVID and COVID periods.

Nowadays, there has been a substantial proliferation in the use of low-cost particulate matter (PM) sensors and facilitating as an indicator of overall air quality. However, during COVID-19 epidemics, air pollution sources have been deteriorated significantly, and given offer to evaluate the impact of COVID-19 on air quality in the world's most polluted city: Delhi, India. To address low-cost PM sensors, this study aimed to a) conduct a long-term field inter-comparison of twenty-two (22) low-cost PM sensors with reference instruments over 10-month period (evaluation period) spanning months from May 2019 to February 2020; b) trend of PM mass and number count; and c) probable local and regional sources in Delhi during Pre-CVOID (P-COVID) periods. The comparison of low-cost PM sensors with reference instruments results found with R2 ranging between 0.74 and 0.95 for all sites and confirm that PM sensors can be a useful tool for PM monitoring network in Delhi. Relative reductions in PM2.5 and particle number count (PNC) due to COVID-outbreaks showed in the range between (2-5%) and (4-13%), respectively, as compared to the P-COVID periods. The cluster analysis reveals air masses originated ∼52% from local, while ∼48% from regional sources in P-COVID and PM levels are encountered 47% and 66-70% from local and regional sources, respectively. Overall results suggest that low-cost PM sensors can be used as an unprecedented aid in air quality applications, and improving non-attainment cities in India, and that policy makers can attempt to revise guidelines for clean air.

Recent Advances on Metal Oxide Based Nano-Photocatalysts as Potential Antibacterial and Antiviral Agents

Photocatalysis, a unique process that occurs in the presence of light radiation, can potentially be utilized to control environmental pollution, and improve the health of society. Photocatalytic removal, or disinfection, of chemical and biological species has been known for decades;however, its extension to indoor environments in public places has always been challenging. Many efforts have been made in this direction in the last two–three years since the COVID-19 pandemic started. Furthermore, the development of efficient photocatalytic nanomaterials through modifications to improve their photoactivity under ambient conditions for fighting with such a pandemic situation is a high research priority. In recent years, several metal oxides-based nano-photocatalysts have been designed to work efficiently in outdoor and indoor environments for the photocatalytic disinfection of biological species. The present review briefly discusses the advances made in the last two to three years for photocatalytic viral and bacterial disinfections. Moreover, emphasis has been given to the tailoring of such nano-photocatalysts in disinfecting surfaces, air, and water to stop viral/bacterial infection in the indoor environment. The role of such nano-photocatalysts in the photocatalytic disinfection of COVID-19 has also been highlighted with their future applicability in controlling such pandemics.

Photocatalytic TiO2 nanomaterials as potential antimicrobial and antiviral agents: Scope against blocking the SARS-COV-2 spread

The whole world is struggling with current coronavirus pandemic that shows urgent need to develop novel technologies, medical innovations or innovative materials for controlling SARS-CoV-2 infection. The mode of infection of SARS-CoV-2 is still not well known and seems to spread through surface, air, and water. Therefore, the whole surrounding environment needs to be disinfected with continuous function. For that purpose, materials with excellent antiviral properties, cost effective, environmental friendly and practically applicable should be researched. Titanium dioxide (TiO2) under ultraviolet light produces strong oxidative effect and is utilized as photocatalytic disinfectant in biomedical field. TiO2 based photocatalysts are effective antimicrobial/antiviral agents under ambient conditions with potential to be used even in indoor environment for inactivation of bacteria/viruses. Interestingly, recent studies highlight the effective disinfection of SARS-CoV-2 using TiO2 photocatalysts. Here, scope of TiO2 photocatalysts as emerging disinfectant against SARS-CoV-2 infection has been discussed in view of their excellent antibacterial and antiviral activities against various bacteria and viruses (e.g. H1N1, MNV, HSV, NDV, HCoV etc.). The current state of development of TiO2 based nano-photocatalysts as disinfectant shows their potential to combat with SARS-CoV-2 viral infection and are promising for any other such variants or viruses, bacteria in future studies.

Update on Coronavirus 2019 Vaccine Guidelines for Transplant Recipients.

The coronavirus disease 2019 (COVID-19) vaccine and its utility in solid organ transplantation need to be timely revised and updated. These guidelines have been formalized by the experts-the apex technical committee members of the National Organ and Tissue Transplant Organization and the heads of transplant societies-for the guidance of transplant communities. We recommend that all personnel involved in organ transplantation should be vaccinated as early as possible and continue COVID-19-appropriate behavior despite a full course of vaccination. For specific guidelines of recipients, we suggest completing the full schedule before transplantation whenever the clinical condition permits. We also suggest a single dose, rather than proceeding unvaccinated for transplant, in case a complete course is not feasible. If vaccination is planned before surgery, we recommend a gap of at least 2 weeks between the last dose of vaccine and surgery. For those not vaccinated before transplant, we suggest waiting 4 to 12 weeks after transplant. For the potential living donors, we recommend the complete vaccination schedule before transplant. However, if this is not feasible, we suggest receiving at least a single dose of the vaccine 2 weeks before donation. We suggest that suitable transplant patients and those on the waiting list should accept a third dose of the vaccine when one is offered to them. We recommend that organs from a deceased donor with suspected/proven vaccine-induced thrombotic thrombocytopenia should be avoided and are justified only in cases of emergency situations with informed consent and counseling.

Deceased-Donor Organ Transplantation in India: Current Status, Challenges, and Solutions.

Tamil Nadu, Gujarat, Telangana, Maharashtra, Kerala, Chandigarh, Karnataka, National Capital Territory of Delhi, and Rajasthan are states and union territories having active deceased-donor organ transplant programs in India. Transplant data (2013-2018) have been collected by the National Organ and Tissue Transplant Organization from all states and union territories of India and submitted to the Global Observatory on Donation and Transplantation. From 2013 to 2018, 49155 transplants were reported in India, including 39000 living-donor organ recipients and 10 155 deceased-donor organ recipients. These transplants were for kidney (living donor = 32584, deceased donor = 5748), liver (living donor = 6416, deceased donor = 2967), heart (deceased donor = 895), lung (deceased donor = 459), pancreas (deceased donor = 78), and small bowel (deceased donor = 8). According to 2018 data, India was the second largest transplanting country in the world in terms of the absolute number of transplants. Here, we discuss the status, progress, challenges, and solutions for deceaseddonor organ transplantation. The plan to increase rates of organ donation in India include the following points: teamwork and focus by intensive care unit doctors; public education on organ donation using social media; professional education and family donation conversation programs for brain death declaration and donor management; organ procurement organizations; international collaboration and regular meetings and updates for organizations working in the field of organ transplantation; grief counseling and reporting of potential donation for families of recently deceased people; nonfinancial incentivization to families of potential organ donors; expert committees and standard operating protocols for use of marginal donor organs, donation after circulatory death programs, and machine perfusion; maintenance of transparency and ethics in organ donation, allocation, and transplantation as directed by governmental, nongovernmental, and intergovernmental entities; and regular audit of progress and registry data.

Nanomedicine strategies to target coronavirus.

With the severe acute respiratory syndrome coronavirus (SARS-CoV) in 2002, the middle east respiratory syndrome CoV (MERS-CoV) in 2012 and the recently discovered SARS-CoV-2 in December 2019, the 21st first century has so far faced the outbreak of three major coronaviruses (CoVs). In particular, SARS-CoV-2 spread rapidly over the globe affecting nearly 25.000.000 people up to date. Recent evidences pointing towards mutations within the viral spike proteins of SARS-CoV-2 that are considered the cause for this rapid spread and currently around 300 clinical trials are running to find a treatment for SARS-CoV-2 infections. Nanomedicine, the application of nanocarriers to deliver drugs specifically to a target sites, has been applied for different diseases, such as cancer but also in viral infections. Nanocarriers can be designed to encapsulate vaccines and deliver them towards antigen presenting cells or function as antigen-presenting carriers themselves. Furthermore, drugs can be encapsulated into such carriers to directly target them to infected cells. In particular, virus-mimicking nanoparticles (NPs) such as self-assembled viral proteins, virus-like particles or liposomes, are able to replicate the infection mechanism and can not only be used as delivery system but also to study viral infections and related mechanisms. This review will provide a detailed description of the composition and replication strategy of CoVs, an overview of the therapeutics currently evaluated in clinical trials against SARS-CoV-2 and will discuss the potential of NP-based vaccines, targeted delivery of therapeutics using nanocarriers as well as using NPs to further investigate underlying biological processes in greater detail.

Benefit to Few Versus Risk to Many: An Ethical Dilemma During Coronavirus Disease 2019 Pandemic for Deceased-Donor Organ Transplant in a Resource-Limited Developing Country.

The tools in our armamentarium to prevent the transmission of coronavirus disease 2019, known as COVID-19, are social distancing; frequent handwashing; use of facial masks; preventing nonessential contacts/travel; nationwide lockdown; and testing, isolation, and contact tracing. However, the World Health Organization's suggestions to isolate, test, treat, and trace contacts are difficult to implement in the resourcelimited developing world. The points to weigh before performing deceased-donor organ transplant in developing countries are as follows: limitations in standard personal protective equipment (as approved by the World Health Organization), testing kits, asymptomatic infections, negative-pressure isolation rooms, intensive care unit beds, ventilator support, telehealth, availability of trained health care workers, hospital beds, the changing dynamic of this pandemic, the unwillingness of recipients, education updates, and additional burdens on the existing health care system. This pandemic has created ethical dilemmas on how to prioritize the use of our facilities, equipment, and supplies in the cash-strapped developing world. We believe that, at the present time, we should aim to resolve the COVID-19 pandemic that is affecting a large sector of the population by diverting efforts from deceased-donor organ transplant. Transplant units should conduct case-bycase evaluations when assessing the convenience of carrying out lifesaving deceased-donor organ transplant, appropriately balanced with the resources needed to address the current pandemic.