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1.
Current Traditional Medicine ; 9(3):28-43, 2023.
Artigo em Inglês | EMBASE | ID: covidwho-2267482

RESUMO

The mass casualties caused by the delta variant and the wave of the newer "Omicron" variant of SARS-COV-2 in India have brought about great concern among healthcare officials. The government and healthcare agencies are seeking effective strategies to counter the pandemic. The application of nanotechnology and repurposing of drugs are reported as promising approaches in the management of COVID-19 disease. It has also immensely boomed the search for productive, re-liable, cost-effective, and bio-assimilable alternative solutions. Since ancient times, the traditional-ly employed Ayurvedic bhasmas have been used for diverse infectious diseases, which are now employed as nanomedicine that could be applied for managing COVID-19-related health anomalies. Like currently engineered metal nanoparticles (NPs), the bhasma nanoparticles (BNPs) are also packed with unique physicochemical properties, including multi-elemental nanocrystalline compo-sition, size, shape, dissolution, surface charge, hydrophobicity, and multi-pathway regulatory as well as modulatory effects. Because of these conformational and configurational-based physico-chemical advantages, Bhasma NPs may have promising potential to manage the COVID-19 pandemic and reduce the incidence of pneumonia-like common lung infections in children as well as age-related inflammatory diseases via immunomodulatory, anti-inflammatory, antiviral, and adju-vant-related properties.Copyright © 2023 Bentham Science Publishers.

2.
Environ Chem Lett ; 21(2): 725-739, 2023.
Artigo em Inglês | MEDLINE | ID: covidwho-2241154

RESUMO

Policies and measures to control pandemics are often failing. While biological factors controlling transmission are usually well explored, little is known about the environmental drivers of transmission and infection. For instance, respiratory droplets and aerosol particles are crucial vectors for the airborne transmission of the severe acute respiratory syndrome coronavirus 2, the causation agent of the coronavirus 2019 pandemic (COVID-19). Once expectorated, respiratory droplets interact with atmospheric particulates that influence the viability and transmission of the novel coronavirus, yet there is little knowledge on this process or its consequences on virus transmission and infection. Here we review the effects of atmospheric particulate properties, vortex zones, and air pollution on virus survivability and transmission. We found that particle size, chemical constituents, electrostatic charges, and the moisture content of airborne particles can have notable effects on virus transmission, with higher survival generally associated with larger particles, yet some viruses are better preserved on small particles. Some chemical constituents and surface-adsorbed chemical species may damage peptide bonds in viral proteins and impair virus stability. Electrostatic charges and water content of atmospheric particulates may affect the adherence of virion particles and possibly their viability. In addition, vortex zones and human thermal plumes are major environmental factors altering the aerodynamics of buoyant particles in air, which can strongly influence the transport of airborne particles and the transmission of associated viruses. Insights into these factors may provide explanations for the widely observed positive correlations between COVID-19 infection and mortality with air pollution, of which particulate matter is a common constituent that may have a central role in the airborne transmission of the novel coronavirus. Supplementary Information: The online version contains supplementary material available at 10.1007/s10311-022-01557-z.

3.
Journal of Hypertension ; 40:e148, 2022.
Artigo em Inglês | EMBASE | ID: covidwho-1937701

RESUMO

Objective: The purpose is to identify the peculiarities of the parameters of red blood cells (RBC) and hemostasis in patients with strokes associated with coronavirus infection. Design and method: A total of 124 patients (48.5 + 1.9 years) with impairments of cerebral circulation due to COVID-19 (confirmed by positive PCR test) had been examined. Among them, 74 patients had ischemic stroke, 25- transient ischaemic attack, 17- intracerebral hemorrhage, 8- subarachnoid hemorrhage. The parameters of hemostasis were measured by standard methods, electrical, viscoelastic parameters of RBC - by dielectrophoresis. Results: 71 patients (the 1st group) showed signs of intravascular coagulation and thrombosis: accelerated platelet-leukocyte aggregation, increased levels of coagulation products, reduced fibrinolysis activity (p = 0.001-0.04). The levels of D-dimer, fibrinogen, ESR, platelet count were higher in this group compared to the second one (p < 0.01). A moderate increase of RBC summarized rigidity, viscosity was noted. The level of RBC hemolysis was associated with platelet count (r = 0.735,p = 0.03), D-dimer (r = 0.482, p < 0.05), fibrinogen level (r = 0.374, p = 0.04). In 2nd group (53 persons), the markers of thrombosis had moderate deviations. Sharply reduced RBC deformability with increased summarized rigidity, viscosity was dominant coupled with the background of high electrical conductivity of cell membranes compared to the indicators in the 1st group (p < 0.01). There was a decrease of membrane capacity, surface charge, cell dipole moment, polarizability than those in the 1st group (p = 0.0001-0.05). A sharp decrease of RBC deformability creates obstacles to overcoming small-diameter capillaries, leading to violations of microcirculatory blood flow. RBC deformability was associated with levels of ferritin (r = 0.451, p = 0.02), HbA1c (r = 0.480, p = 0.03), uric acid (r = -0.371, p < 0.05), LDL cholesterol (r = 0.461, p = 0.02). Incubation of blood samples in vitro for 10 min with riboflavin, nicotinamide, inosine, which ensures RBC energy metabolism, restored the reduced RBC deformability (p < 0.01), altered cell morphology (p = 0.04), decreased RBC aggregation (p < 0.001). Conclusions: The revealed features of parameters of RBC hemostasis in stroke patients with coronavirus infection are associated with two independent pathogenetic mechanisms: thrombotic and hemorheologic. The thrombotic variant is due to procoagulant state and an activity of inflammation. The hemorheologic variant is caused by decrease of RBC energy metabolism, activity of enzymes.

4.
Pharmaceutics ; 14(7)2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: covidwho-1928624

RESUMO

Nearly four million yearly deaths can be attributed to respiratory diseases, prompting a huge worldwide health emergency. Additionally, the COVID-19 pandemic's death toll has surpassed six million, significantly increasing respiratory disease morbidity and mortality rates. Despite recent advances, it is still challenging for many drugs to be homogeneously distributed throughout the lungs, and specifically to reach the lower respiratory tract with an accurate sustained dose and minimal systemic side effects. Engineered nanocarriers can provide increased therapeutic efficacy while lessening potential biochemical adverse reactions. Poly(lactic-co-glycolic acid) (PLGA), a biodegradable polymer, has attracted significant interest as an inhalable drug delivery system. However, the influence of the nanocarrier surface charge and its intratracheal instillation has not been addressed so far. In this study, we fabricated red fluorescent PLGA nanocapsules (NCs)-Cy5/PLGA-with either positive (Cy5/PLGA+) or negative surface charge (Cy5/PLGA-). We report here on their excellent colloidal stability in culture and biological media, and after cryo-storage. Their lack of cytotoxicity in two relevant lung cell types, even for concentrations as high as 10 mg/mL, is also reported. More importantly, differences in the NCs' cell uptake rates and internalization capacity were identified. The uptake of the anionic system was faster and in much higher amounts-10-fold and 2.5-fold in macrophages and epithelial alveolar cells, respectively. The in vivo study demonstrated that anionic PLGA NCs were retained in all lung lobules after 1 h of being intratracheally instilled, and were found to accumulate in lung macrophages after 24 h, making those nanocarriers especially suitable as a pulmonary immunomodulatory delivery system with a marked translational character.

5.
Journal of Aerosol Medicine and Pulmonary Drug Delivery ; 35(2):A7, 2022.
Artigo em Inglês | EMBASE | ID: covidwho-1815947

RESUMO

The work led to the formulation of a powder of calcium phosphate coated liposomes containing cyclosporine A (CsA). The formulation was designed to reduce the dose of CsA to be administered following lung transplantation. Potentially this formulation can be used also to contain the inflammatory process due to SARS-CoV-2. Calcium phosphate (CaP) is a material found in bones and teeth and considered non-toxic and biocompatible and this coating could reduce the recognition by alveolar macrophages and increase the cell uptake. Moreover, CaP is insoluble at physiological pH (7.4), while it solubilizes easily at pH below 5. This could favor drug release in the cell after pinocytosis and in inflamed tissues, while reducing drug release at physiological pH [1]. The liposomes produced were evaluated in terms of size, surface charge and drug loading. The presence of the CaP coating was verified by calcium titration, variation of the zeta potential and by cryogenic transmission electron microscopy (cryo-TEM). The highest loading was obtained in the formulation containing CsA at 7% (w/w). Cholesterol was added to liposomes at two different concentrations in order to improve the stability of the nanostructure and reduce the drug leakage. However, cholesterol did not bring any improvement to the formulation. The inhalation powder produced by spray drying with the best aerosolization performance (fine particle fraction of coated liposomes powder 33.69 - 1.6% and 50.50- 0.6% for the uncoated liposomes powder) was obtained using a 1:3 weight ratio between liposomes and excipients using mannitol as bulking agent and 15% L-leucine. Key Message: This work aimed to develop a respirable dry powder for inhalation containing CsA for the local treatment of lung immune diseases. CsA was efficiently loaded into CaP-coated liposomes and transformed into a respirable powder by spray-drying. The inhaled immunosuppressive product would offer multiple advantages related to drug deposition at the target site. Furthermore, the coating of the liposomes governs the release of the drug which will occur only at only at biological acidic conditions.

6.
ACS Appl Mater Interfaces ; 12(43): 48284-48295, 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: covidwho-872635

RESUMO

Protein nanoparticles are biomaterials composed entirely of proteins, with the protein sequence and structure determining the nanoparticle physicochemical properties. Upon exposure to physiological or environmental fluids, it is likely that protein nanoparticles, like synthetic nanoparticles, will adsorb proteins and this protein corona will be dependent on the surface properties of the protein nanoparticles. As there is little understanding of this phenomenon for engineered protein nanoparticles, the purpose of this work was to create protein nanoparticles with variable surface hydrophobicity and surface charge and establish the effect of these properties on the mass and composition of the adsorbed corona, using the fetal bovine serum as a model physiological solution. Albumin, cationic albumin, and ovalbumin cross-linked nanoparticles were developed for this investigation and their adsorbed protein coronas were isolated and characterized by gel electrophoresis and nanoliquid chromatography mass spectrometry. Distinct trends in corona mass and composition were identified for protein nanoparticles based on surface charge and surface hydrophobicity. Proteomic analyses revealed unique protein corona patterns and identified distinct proteins that are known to affect nanoparticle clearance in vivo. Further, the protein corona influenced nanoparticle internalization in vitro in a macrophage cell line. Altogether, these results demonstrate the strong effect protein identity and properties have on the corona formed on nanoparticles made from that protein. This work builds the foundation for future study of protein coronas on the wide array of protein nanoparticles used in nanomedicine and environmental applications.


Assuntos
Macrófagos/metabolismo , Nanopartículas/química , Coroa de Proteína/química , Adsorção , Humanos , Interações Hidrofóbicas e Hidrofílicas , Macrófagos/química , Tamanho da Partícula , Coroa de Proteína/metabolismo , Propriedades de Superfície
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