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1.
IPPTA: Quarterly Journal of Indian Pulp and Paper Technical Association ; 34(1):43-46, 2022.
Artigo em Inglês | Scopus | ID: covidwho-20242893

RESUMO

The biggest issue before pulp and paper producers is availability of quality raw material. India is fiber deficit country, this message has become more intense after covid when price of different raw materials are increased by 20-25%, . Chemical pulp is produced by chemical delignification of wood and non-wood plants. After kraft pulping the remaining lignin is removed by oxygen delignification and bleaching to produce higher purity cellulosic pulp. The goal of delignification processes is to remove lignin from the raw material without a negative effect on the cellulose and strength of pulp. The economics of pulp and paper production is more related to the yield of unbleached and bleached pulp production. Marginal increment in pulp yield reflects into savings of crore of rupees on yearly basis. An overall vigilant concern on process conditions and variables is required during production of pulp. BAT technology for pulping along with utilization of various additives and pretreatment methods allow to fine tune these process to obtain pulp with desired yield and quality. The primary aim of this paper is to review different process variables in respect to the yield of the pulp. © 2022 Indian Pulp and Paper Technical Association. All rights reserved.

2.
International Journal of Applied Pharmaceutics ; 15(3):1-11, 2023.
Artigo em Inglês | EMBASE | ID: covidwho-20242785

RESUMO

Recent advancements in nanotechnology have resulted in improved medicine delivery to the target site. Nanosponges are three-dimensional drug delivery systems that are nanoscale in size and created by cross-linking polymers. The introduction of Nanosponges has been a significant step toward overcoming issues such as drug toxicity, low bioavailability, and predictable medication release. Using a new way of nanotechnology, nanosponges, which are porous with small sponges (below one microm) flowing throughout the body, have demonstrated excellent results in delivering drugs. As a result, they reach the target place, attach to the skin's surface, and slowly release the medicine. Nanosponges can be used to encapsulate a wide range of medicines, including both hydrophilic and lipophilic pharmaceuticals. The medication delivery method using nanosponges is one of the most promising fields in pharmacy. It can be used as a biocatalyst carrier for vaccines, antibodies, enzymes, and proteins to be released. The existing study enlightens on the preparation method, evaluation, and prospective application in a medication delivery system and also focuses on patents filed in the field of nanosponges.Copyright © 2023 The Authors.

3.
Current Materials Science ; 16(4):376-399, 2023.
Artigo em Inglês | Scopus | ID: covidwho-20242773

RESUMO

Nanofibers are a type of nanomaterial with a diameter ranging from ten to a few hundred nanometers with a high surface-to-volume ratio and porosity. They can build a network of high-porosity material with excellent connectivity within the pores, making them a preferred option for numerous applications. This review explores nanofibers from the synthesis techniques to fabricate nanofibers, with an emphasis on the technological applications of nanofibers like water and air filtration, photovoltaics, batteries and fuel cells, gas sensing, photocatalysis, and biomedical applications like wound dressing and drug delivery. The nanofiber production market has an expected compound annual growth rate (CAGR) of 6% and should reach around 26 million US $ in 2026. The limitations and potential opportunities for large-scale applications of nano-fibrous membranes are also discussed. We expect this review could provide enriched information to better understand Electrospun Polymer Nanofiber Technology and recent advances in this field. © 2023 Bentham Science Publishers.

4.
Journal of International Business Education ; 17:313-326, 2022.
Artigo em Inglês | Scopus | ID: covidwho-20242772

RESUMO

The Indian government had been making efforts to foster an innovative business culture by incorporating design thinking and innovation in b-school curricula. Substantial investments had also helped aspiring entrepreneurs pursue their ambitions. One such beneficiary of these initiatives was Preheal Innovations Private Limited, which aimed to build an online platform catering to the healthcare, beauty, and wellness needs of customers throughout India. Mr. Vikrant, founder and CEO of Preheal, had built a robust network of contacts in the healthcare sector after 20 years of experience and this, combined with the company's unique business model catering to customers in both urban (tier-2 and tier-3 cities) and rural areas in India, played a key role in attracting the initial start-up team. However, efforts were interrupted due to COVID-19, which lead to the departure of team members. Post lockdown, Mr. Vikrant had to decide how to relaunch the new venture with either full or partial staffing, in a changed business environment. © 2022 NeilsonJournals Publishing.

5.
Journal of Small Business Strategy ; 33(1):70-83, 2023.
Artigo em Inglês | Scopus | ID: covidwho-20242770

RESUMO

The pandemic has raised an issue of survival for most of the micro, small, and medium enterprises (MSMEs) because of their vulnerability in terms of size, limited financial resources, and inefficiency to deal with unpredicted situations. Therefore, the present study has adopted the contingency theory in times of change and uncertainties caused by COVID-19 on MSMEs and found out the ways to enhance its resilience and sustained the growth of this sector. This study has applied descriptive statistics and probit regression analysis to estimate the resilience and sustained growth of the firms through a change in the variables like turnover, labour employed, investment, and age of the firm. Based on the survey of 225 firms, the study observed that around 90 percent of surveyed firms realized a decline in their turnover with a 25 percent reduction in employment that mostly occur in the informal category. Interestingly, there was some increase in formal employment in around 50 percent of firms because of the business commitment of firms, shortage of informal workers, and availability of workers at lower wages. Smaller and younger firms in terms of employment and investment have a higher possibility to be affected by the external shocks indicating that the firm agility increases with firm age and size. Support measures by the government during the pandemic were found to be insufficient and have limited relevance to the MSME sector in its revival. For enhancing the resilience and sustainability of MSMEs, the study suggests small firms should be encouraged to financial planning against business uncertainties and proposes financial security measures viz. Uncertainty Corpus Fund for Small Businesses and Small Business Insurance. © 2023, Small Business Institute. All rights reserved.

6.
2023 3rd International Conference on Advances in Electrical, Computing, Communication and Sustainable Technologies, ICAECT 2023 ; 2023.
Artigo em Inglês | Scopus | ID: covidwho-20242769

RESUMO

Monkeypox is a skin disease that spreadsfrom animals to people and then people to people, the class of the monkeypox is zoonotic and its genus are othopoxvirus. There is no special treatment for monkeypox but the monkeypox and smallpox symptoms are almost similar, so the antiviral drug developed for prevent from smallpox virus may be used for monkeypox Infected person, the Prevention of monkeypox is just like COVID-19 proper hand wash, Smallpox vaccine, keep away from infected person, used PPE kits. In this paper Deep learning is use for detection of monkeypox with the help of CNN model, The Original Images contains a total number of 228 images, 102 belongs to the Monkeypox class and the remaining 126 represents the normal. But in deep learning greater amount of data required, data augmentation is also applied on it after this the total number of images are 3192. A variety of optimizers have been used to find out the best result in this paper, a comparison is usedbased on Loss, Accuracy, AUC, F1 score, Validation loss, Validation accuracy, validation AUC, Validation F1 score of each optimizer. after comparing alloptimizer, the Adam optimizer gives the best result its total testing accuracy is 92.21%, total number of epochs used for testing is 100. With the help of deep learning model Doctors are easily detect the monkeypox virus with the single image of infected person. © 2023 IEEE.

7.
Current Psychiatry Research and Reviews ; 19(3):241-261, 2023.
Artigo em Inglês | EMBASE | ID: covidwho-20237582

RESUMO

Background: The outbreak of the COVID-19 pandemic, the constant transformation of the SARS-COV-2 virus form, exposure to substantial psychosocial stress, environmental change, and isolation have led to the inference that the overall population's mental health could be affected, resulting in an increase in cases of psychosis. Objective(s): We initiated a systematic review to determine the impact of the SARS-COV-2 virus and its long-term effects-in both symptomatic and asymptomatic cases-on people with or without psychosis. We envisioned that this would give us an insight into effective clinical intervention methods for patients with psychosis during and after the pandemic. Method(s): We selected fifteen papers that met our inclusion criteria, i.e., those that considered participants with or without psychiatric illness and exposed to SARS-COV-2 infection, for this review and were retrieved via Google, Google Scholar, MEDLINE, PubMed, and PsychINFO Database. Key Gap: There is a dearth of research in understanding how COVID-19 affects people with or without a prior personal history of psychosis. Result(s): The systematic review summary provides insight into the state of knowledge. Insights from the systematic review have also been reviewed from the salutogenesis model's perspec-tive. There is moderate evidence of new-onset psychosis during the COVID-19 pandemic in which some antipsychotics treated the psychotic symptoms of patients while treating for COVID-19. Suggestions and recommendations are made for preventive and promotive public health strategies. Conclusion(s): The Salutogenesis model and Positive Psychology Interventions (PPI) provide another preventive and promotive public health management approach.Copyright © 2023 Bentham Science Publishers.

8.
Plants and Phytomolecules for Immunomodulation: Recent Trends and Advances ; : 285-320, 2022.
Artigo em Inglês | Scopus | ID: covidwho-20234376

RESUMO

There are numerous foods and herbal plants that boost the immune system. They stimulate the activity of cells responsible for fighting infections. In fact, over centuries, people have relied on herbs and other plants for treating medical conditions and boosting immunity. Considering the worldwide coronavirus pandemic, natural immune boosters are being sought after in the current war against this viral infection. Most likely, immune-boosting plants help human health by tackling viruses, bacteria, and abnormal cells in the form of prevention, to support and strengthen the body's natural immune system. In this chapter, we review several terrestrial species and plants from various sources including China, India, Europe, and Africa, which have long folklore use, and we provide information on the chemistry and biological activity where available. © The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2022.

9.
Journal of Zoonotic Diseases ; 7(1):199-206, 2023.
Artigo em Inglês | Scopus | ID: covidwho-20232279

RESUMO

While the world is still trying to emerge from the crisis due to the COVID-19 pandemic, and all the nations are trying to nullify the repercussions caused by it;another outbreak known as the monkeypox virus (MPXV) has recommenced. Human monkeypox, a rare viral zoonosis (an infectious disease that can be transferred from non-human animals to humans), is caused by the MPXV, a member of the genus Orthopoxvirus (family Poxviridae, subfamily Chordopoxvirinae). Since eradicating smallpox globally in 1977, monkeypox has been the primary orthopoxvirus infection in humans. On July 14, 2022, the first case in India was reported in the Kollam district of Kerala. It manifests with the same symptoms as smallpox, including flu-like symptoms, fever, malaise, headache, back pain, and a characteristic rash. New medications have shown promising results, but more study is needed for the drug's efficacy in endemic settings. The monkeypox virus is a high-danger pathogen that causes a significant disease for public health. Consequently, there is a pressing need to develop surveillance capabilities that can yield valuable data for creating suitable preventative, preparedness, and response operations. © 2023,.

10.
Int J Environ Sci Technol (Tehran) ; : 1-16, 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: covidwho-20237633

RESUMO

Amid COVID-19, world has gone under environmental reformation in terms of clean rivers and blue skies, whereas, generation of biomedical waste management has emerged as a big threat for the whole world, especially in the developing nations. Appropriate biomedical waste management has become a prime concern worldwide in the pandemic era of COVID-19 as it may affect environment and living organisms up to a great extent. The problem has been increased many folds because of unexpected generations of hazardous biomedical waste which needs extraordinary attentions. In this paper, the impacts and future challenges of solid waste management especially the biomedical waste management on environment and human beings have been discussed amid COVID-19 pandemic. The paper also recommends some guidelines to manage the bulk of medical wastes for the protection of human health and environment. The paper summarizes better management practices for the wastes including optimizing the decision process, infrastructure, upgrading treatment methods and other activities related with the biological disasters like COVID-19. As achieved in the past for viral disinfection, use of UV- rays with proper precautions can also be explored for COVID-19 disinfection. For biomedical waste management, thermal treatment of waste can be an alternative, as it can generate energy along with reducing waste volume by 80-95%. The Asian Development Bank observed that additional biomedical waste was generated ranged from 154 to 280 tons/day during the peak of COVID-19 pandemic in Asian megacities such as Manila, Jakarta, Wuhan, Bangkok, Hanoi, Kuala Lumpur.

11.
Delineating Health and Health System: Mechanistic Insights into Covid 19 Complications ; : 401-418, 2021.
Artigo em Inglês | Scopus | ID: covidwho-2326236

RESUMO

SARS-CoV-2, a member of the family Coronaviridae, is a positive-stranded RNA virus with the spike glycoproteins present on its envelope. ACE2 serves as the entry mediator of SARS-CoV-2 as it attacks mainly the organs of the respiratory, cardiovascular, digestive, and urinary system showing high expression of ACE2 or TMPRSS2. ACE2 is found to have significant differential expression in all the reproductive tissues, thus posing the reproductive system vulnerable to the adverse effects of SARS-CoV-2 infection. Previous coronavirus attacks (SARSCoV and MERS) have also been known to impose adverse effects on the reproductive system. Therefore, there is a dire need to safeguard the reproductive system against COVID-19 as it not only bothers the present generation but may also affect the well-being of future progeny. Since the inception of pandemic, several scientific studies have been carried out to assess its impact;yet there are research lacunas to claim reproductive system as a potential target of this deadly virus. To avoid the detrimental effects of the current pandemic on reproductive sustainability, well-planned large-scale and multicentric cohort follow-up studies are mandatory for accurate evaluation of the enduring effects of SARS-CoV-2 infection on human fertility and pregnancy outcomes. © The Author(s), under exclusive licence to Springer Nature Singapore Pte Ltd. 2021.

12.
Journal of Economic Studies ; 2023.
Artigo em Inglês | Scopus | ID: covidwho-2326234

RESUMO

Purpose: The study focuses on examining the impact of the supply shock on the Indian macroeconomic variables during the COVID-19 period. Design/methodology/approach: Time-varying factor augmented vector autoregressive model has been employed to study the asymmetry in transmission of supply shock on Indian economy during pre- and post-COVID-19 times. Findings: The authors find that with supply shock, retail food inflation outpaced in COVID-19 times. Production levels reported by IIP fell to abysmally low levels in the post-COVID-19 times when the economy stalled. The liquidity stimulus provided by the central bank led to the negative response of policy rates to the supply shocks during the COVID-19 times. Originality/value: The study stands novel in examining the impact of COVID-19 pandemic on Indian economy through the lenses of asymmetric transmission of supply shock during pre- and post-COVID-19 times. © 2023, Emerald Publishing Limited.

13.
Indian Veterinary Journal ; 100(2):12-19, 2023.
Artigo em Inglês | EMBASE | ID: covidwho-2326230

RESUMO

The occurrence of Cryptosporidium species infection and its risk factors in neonatal goats is less explored. Also it is due to the fact that diseases like colibacillosis and neonatal viral enteritis complex caused by Group A rotaviruses and Bovine corona viruses can co-exist with Cryptosporidium and can lead to mixed infections and the latter is often overlooked. Therefore, in the current research we explored the cryptosporidial occurrence in neonatal goats of Mathura district of Uttar Pradesh, India. In this study, a total of 644 faecal samples were collected from neonatal goats at different villages and certain organized farms of Mathura district age-wise, season-wise and breed-wise, and were examined for Cryptosporidium based on modified Ziehl-Neelsen technique, conventional 18SSU rRNA nested PCR assay. The overall prevalence of Cryptosporidium infection in goats based on microscopy was 36.80% (237/644;p value <0.0001) and 18SSU rRNA nested PCR 52.95% (341/644;p value <0.0001) respectively. Cryptosporidium species typing was also done using 18SSU rRNA nested PCR-RFLP product using enzymes Mbo-II, Ssp-I and Vsp-I, which revealed species including C. parvum C. bovis, C. ryanae, C. hominis and C. andersoni. Also the infection was clinically associated based on age, gender and seasons to identify the causal relationships that precipitate the cryptosporidial infection in goat kids. Since mZN microscopy based screening requires expertise and may sometimes be confuse with other weak acid fast bodies and also due to low sensitivity, combination of diagnostic tests are used in this study to identify the best test combination that yields best statistical fit in terms of kappa-agreement and McNemar's test. Cryptosporidiosis is caused by an enteric protozoan parasite and the first report in sheep and goat was observed in early 1980s, with other important etiological agents for neonatal diarrhoea, mortality and morbidity in neonatal kids and lambs, responsible for economic losses.Copyright © 2023 Indian Veterinary Assocaition. All rights reserved.

14.
Delineating Health and Health System: Mechanistic Insights into Covid 19 Complications ; : 333-347, 2021.
Artigo em Inglês | Scopus | ID: covidwho-2326229

RESUMO

The last discovered organ of the human body is microbiome which is present at different sites in it. Gut microbiome consists of about 1000–1500 bacterial species and as regulated by genetic makeup, lifestyle, and environmental conditions, the gut microbiota of a healthy individual can comprise approximately 160 species of bacteria. Majority of gut microbiome consists of Firmicutes, Actinobacteria, Bacteroidetes, and to a lesser extent Proteobacteria, Euryarchaeota, Fusobacteria, and Verrucomicrobia. The gut-lung axis is involved in the migration of immune cells from gut to respiratory tract through circulation and encourages the host's ability to fight infections. The gut regulates the responses in lungs via host-acquired inflammatory mediators in the circulation. Dendritic cells located in the Peyer's patches of the intestine, macrophages, and Langerhans cells are the major antigen-presenting cells that play a vital role in the modulation and development of innate immune response. Gut microbiota interacts via the regulation and development of adaptive immune response. B and T lymphocytes are the key players of adaptive immunity. CD4 + T cells after activation differentiate into four major kinds of cell classes: (1) regulatory T cells (Treg), (2) Th2, (3) Th1, and (4) Th17 cells. Gut microbial interactions can induce the production of various types of immune cells as demonstrated by various studies. For instance, Clostridia induces the formation of Treg cells. Likewise, Bacteroides fragilis inhabiting the gut can incite the production of Th1 cells and production of T17 cells is stimulated by segmental filamentous bacteria. Gut microbiota also plays a vital role in the physiology and metabolism leading to the synthesis of various immunoregulatory metabolites such as SCFAs, antimicrobial peptides (AMPs), amino acids, and polyamines. SARS-CoV-2 virus entry to the cell is via ACE2 receptor present in respiratory epithelium and gut epithelium. This receptor is highly expressed (100 times more than in the lung) in the epithelial cells of the stomach, duodenum, ileum, and rectum as well as cholangiocytes and hepatocytes. High level of ACE2 receptor expressing in the gastrointestinal epithelial cells along with high-level co-expression of TMPRSS2 (cellular serine peptidase) causes coronavirus to infect gastrointestinal tract along with lungs leading to altered intestinal permeability and enterocyte malabsorption with symptoms of diarrhea in patients of COVID-19. Hence, COVID-19 patients with gastrointestinal symptoms have significantly longer duration of illness and viral clearance time than patients without any gastrointestinal symptoms. Obese patients with gut dysbiosis have decreased population of Bacteroides species. COVID-19 patients with type 2 diabetics have increased population of Fusobacterium, Ruminococcus, and Blautia with decreased population of Bacteroides, Bifidobacterium, Faecalibacterium, Akkermansia, and Roseburia. Diet with low fiber, high fat, and high carbohydrate causes gut dysbiosis. Intake of high-fiber diet consisting of whole grains, vegetables, and fruits induces growth of Bifidobacterium, Bacteroides, and Lactobacilli. Probiotics are nonpathogenic live organisms which are safe to be taken as dietary supplements. The major genera of probiotics are Lactobacillus, Bifidobacterium, and Saccharomyces. These probiotics increase the activity of T cells, NK cell, and polymorphonuclear cells. Prebiotics in the form of maize fiber, inulin, and polydextrose improves digestion and immunity. Hence, healthy gut microbiome with its strong immune intervention may bring recovery in COVID-19 patients. However, so far no published studies have reported that probiotics can be used as an adjunctive therapy in our fight against the SARS-CoV-2 infection. A far-reaching approach should consist of randomized, multicenter, controlled trials to explore the potential benefits of gut microbiome and how changes in dietary habits can be used as an add-on strategy against the COVID-19 pandemic. © The Author(s), under exc us ve licence to Springer Nature Singapore Pte Ltd. 2021.

15.
Future of Tourism in Asia ; : 1-312, 2022.
Artigo em Inglês | Scopus | ID: covidwho-2326228

RESUMO

This book offers a meticulous overview of the future of tourism in Asian countries. This book provides new dimensions to the tourism research and tourism industry as it is concerned with the future vision of tourism in Asia. The main purpose of the book is to envision the outcomes both positive and negative from the tourism industry to prepare our future generations. This book expands on the concept that tourism is not sedentary and is ever changing rapidly. A unique feature of the book is that it brings into limelight the unexplored places of Asia as well as a growth of low-cost tourism in Asia This book discusses how Asia can enjoy the competitive advantage in future. Also, whether the future outlook is bright or dark for the tourism sector in the Asia region. This book highlights the unexplored themes of tourism in Asia such as Over-tourism, Sports Tourism, Baby Boomers and Seenger Tourism, Literary Tourism, Experiential Tourism, Psychographic Segmentation of Future Tourists. The chapters have been authored by experts in their respective fields. This book allows readers to explore how different Asian countries might best serve tourism products in the future. © The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2021.

17.
Topics in Antiviral Medicine ; 31(2):439, 2023.
Artigo em Inglês | EMBASE | ID: covidwho-2320463

RESUMO

Background: The COVID-19 pandemic resulted in disruptions to health care services. Vulnerable populations, including people living with HIV (PLHIV), may have experienced unique challenges when accessing medical care. The objective of this study was to evaluate the impact of social disruptions on health care visits among Multicenter AIDS Cohort Study/Women's Interagency HIV Study Combined Cohort Study (MWCCS) participants. Method(s): A survey collecting data on missed health care visits and social disruptions (i.e., disruptions in employment, childcare, financial support, housing, and health insurance) during the pandemic was administered via telephone to MWCCS participants 1-3 times from March and September 2020. Logistic regression models adjusted for sociodemographics and HIV-status were used to test the association between social disruptions and three medical care interruption outcomes (i.e., missed healthcare appointment, interruption of mental health care, and interruption of substance use care). Result(s): Surveys (n=10,076) were conducted among 2238 PLHIV (61% women) and 1427 people living without HIV (PLWoH) (41% women). Overall, 42% of participants reported disruptions in health care with no significant difference by HIV status. Among participants receiving mental health care services and substance use treatment, 52% and 36% reported interruptions of care, respectively. Participants reporting >= 2 social disruptions were more likely to report missed health care appointments (adjusted odds ratio [aOR]: 1.81, 95% confidence interval [CI]: 1.54-2.13), and interruptions in mental health care [aOR: 2.42, 95%CI: 1.85-3.17) or substance use treatment (aOR: 1.97, 95%CI: 1.26-3.09), compared to those reporting no disruptions. Participants who were unemployed were more likely to miss health care appointments (aOR:1.46, 95% CI: 1.25-1.71) and report disruptions in mental health care (aOR: 2.02, 95% CI: 1.54-2.66) compared to those who were employed. PLHIV reporting >= 2 social disruptions were at increased risk for missed health care appointments (aOR 1.92, 95%CI: 1.56-2.36) and disruptions in mental health care (aOR: 2.54, 95%CI: 1.83-3.53 (Table 1). Conclusion(s): Social disruptions as a result of the COVID-19 pandemic have adversely impacted the receipt of health care among PLHIV and PLWoH, including the receipt of treatment for mental health and substance abuse. Providing childcare, financial support, housing, and health insurance may reduce disruptions in care and improve health outcomes.

18.
Topics in Antiviral Medicine ; 31(2):117, 2023.
Artigo em Inglês | EMBASE | ID: covidwho-2314619

RESUMO

Background: Individuals living with HIV are at increased risk of morbidity and mortality from COVID-19. Furthermore, SARS-CoV-2 infection in immunocompromised HIV infected individuals poses a risk to prolonged infection and viral shedding and the emergence of new variants of concern (VOCs). Using the SIV macaque model for AIDS, we are investigating the hypothesis that immune dysfunction during HIV infection will prolong SARSCoV- 2 viral infection, promote enhanced COVID-19 disease, and accelerate viral evolution. Here, we report the impact of SIV-CoV-2 co-infection on immune responses and pathogenesis. Method(s): Eight female rhesus macaques (aged 7-15 years, 5.5-9.9kg) were infected with SIVmac251 via low dose intravaginal challenge and then inoculated with 6.5x105 TCID50/mL SARS-CoV-2 (WA-1) at 17-34 weeks post-SIV infection via combined intranasal and intratracheal routes. Blood, bronchoalveolar lavage (BAL), stool, and nasal, oral, and rectal swabs were collected pre-infection through 14 days post-infection (DPI) to measure immune responses and viremia. ELISAs, ELISPOT, qRT-PCR, lung pathology, cytokine multiplex, and virus neutralization assays were performed to measure viral loads, pathogenesis, and immune responses. Result(s): Three days post-SARS-CoV-2 infection, we observed a transient decrease in CD4 counts, but there were no changes in clinical symptoms or plasma SIV viral loads. However, SARS-CoV-2 replication persisted in the upper respiratory tract, but not the lower respiratory tract. In addition, SARS-CoV-2 IgG seroconversion was delayed and antigen-specific T-cell responses were dampened. Notably, viral RNA levels in nasal swabs were significantly higher 7-14 DPI in SIV+ compared to previously published results using the same SARS-CoV-2 challenge virus in SIV- rhesus (PMCID: PMC8462335, PMC8829873). In addition, SIV/CoV-2 co-infected animals exhibited elevated levels of myeloperoxidase (MPO), a marker of neutrophil activation and increased lung inflammation. Conclusion(s): Here we provide evidence for the utility of the rhesus macaque in modeling human HIV-SARS-CoV-2 co-infection. Our results suggest that immunosuppression during SIV infection impairs de novo generation of anti-SARS-CoV-2 immunity, that may contribute to prolonged SARS-CoV-2 viral shedding, increased transmission windows, altered disease pathogenesis, and lower protection against subsequent SARS-CoV-2 exposures. Studies in progress will determine if SARS-CoV-2 viral evolution is accelerated in SIV-infected macaques.

19.
Topics in Antiviral Medicine ; 31(2):112, 2023.
Artigo em Inglês | EMBASE | ID: covidwho-2313242

RESUMO

Background: The disparity in COVID-19 disease burden between European, Asian, and African countries is notable, with considerably higher morbidity and mortality in many European countries as well as the U.S. Dietary differences between regions could play a role in differential COVID-19 pathogenesis, as Western diets high in fat and sugar have been implicated in enhancing gut damage and pathogenesis during viral infections. Here we investigate the effect of diet on gut immunity and SARS-CoV-2 infection. Method(s): Six pigtail macaques were fed a commercial monkey chow diet, then transitioned to a high fat and sugar chow diet (HFD) for approximately two months prior to infection with Delta strain SARS-CoV-2. Animals were sampled prior to HFD initiation, during HFD administration but prior to infection, and for approximately one month post-infection. HFD was maintained following infection and animals were euthanized at the study conclusion. Result(s): Viral RNA was detected for up to 28 days post-infection in nose swabs, with peak viral load at day 2 at a mean of 8.2x109 copies/mL of swab fluid. Subgenomic RNA (sgRNA, indicating viral replication) decayed more rapidly, with all animals having undetectable sgRNA by day 21, and a lower peak of 2.6x109 copies/mL swab fluid on day 2. Viral RNA load was approximately 3.5 logs greater and sgRNA load approximately 3 logs higher at day 2 than in rhesus macaques infected with WA2020 SARS-CoV-2 and fed standard monkey chow. Mucosal rectal biopsies indicated significantly lower B cell frequencies from baseline to approximately two months following HFD administration (p=0.04, Dunn's), and frequencies had not recovered approximately one month postinfection. GI tract-resident IgG+ B cells were nearly absent at necropsy, with mean frequency 0.03% of total B cells. B cell loss was coupled with modest T cell expansion during HFD administration, though frequencies declined following infection. Furthermore, NK cell frequencies tended to decline from baseline throughout HFD administration, and were further depleted at necropsy one month post-infection. Conclusion(s): SARS-CoV-2 infection can induce lymphopenia, and our sampling of gut mucosal tissue indicates B cell depletion and NK cell loss with a HFD that is further exacerbated by SARS-CoV-2 infection. Excess dietary fat and sugar may disrupt gut barrier integrity and immunity, in turn predisposing the tissue to pathology of viral infection.

20.
Applications of Machine Learning and Deep Learning on Biological Data ; : 57-74, 2023.
Artigo em Inglês | Scopus | ID: covidwho-2312210

RESUMO

Machine learning and deep learning are aspects of artificial intelligence (AI) that help us to make the applications more accurate at predicting some real-life phenomenon without being specifically programmed or designed to do so. In this book chapter, we have discussed the COVID-19 virus, the importance of using face masks, and the existing models of face mask detection. The book chapter is analyzing the current model of sending an alert when a person is detected not wearing a mask and also comments on the improvements that can be done in the model. With the use of a ‘convolutional neural network,' we are making this model more efficient. We are attempting to briefly explain the model of face mask detection using various python libraries and deep learning efficiently. © 2023 Taylor & Francis Group, LLC.

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