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1.
J Mater Chem B ; 11(29): 6911-6921, 2023 07 26.
Article in English | MEDLINE | ID: mdl-37379103

ABSTRACT

Photothermal therapy utilizes photothermal agents and the use of nanoparticle agents is deemed advantageous for multiple reasons. Common nano-photothermal agents normally have high conversion efficiencies and heating rates, but bulk temperature measurement methods do not adequately represent the nanoscale temperatures of these nanoheaters. Herein, we report on the fabrication of self-limiting hyperthermic nanoparticles that can simultaneously photoinduce hyperthermia and report back temperature ratiometrically. The synthesized nanoparticles utilize a plasmonic core to achieve the photoinduced hyperthermic property and fluorescent FRET pairs entrapped in a silica shell to impart the ratiometric temperature sensing ability. The studies demonstrate the photoinduced hyperthermia with simultaneous temperature measurement using these particles and show that the particles can achieve a conversion efficiency of 19.5% despite the shell architecture. These folate-functionalized self-limiting photothermal agents are also used to demonstrate targeted photoinduced hyperthermia in a HeLa cell model.


Subject(s)
Hyperthermia, Induced , Nanoparticles , Humans , HeLa Cells , Photothermal Therapy , Hyperthermia, Induced/methods , Phototherapy/methods
2.
Pathogens ; 12(2)2023 Jan 25.
Article in English | MEDLINE | ID: mdl-36839456

ABSTRACT

Recent evidence relating to the impact of COVID-19 on people with diabetes is limited but continues to emerge. COVID-19 pneumonia is a newly identified illness spreading rapidly throughout the world and causes many disabilities and fatal deaths. Over the ensuing 2 years, the indirect effects of the pandemic on healthcare delivery have become prominent, along with the lingering effects of the virus on those directly infected. Diabetes is a commonly identified risk factor that contributes not only to the severity and mortality of COVID-19 patients, but also to the associated complications, including acute respiratory distress syndrome (ARDS) and multi-organ failure. Diabetic patients are highly affected due to increased viral entry into the cells and decreased immunity. Several hypotheses to explain the increased incidence and severity of COVID-19 infection in people with diabetes have been proposed and explained in detail recently. On the other hand, 20-50% of COVID-19 patients reported new-onset hyperglycemia without diabetes and new-onset diabetes, suggesting the two-way interactions between COVID-19 and diabetes. A systematic review is required to confirm diabetes as a complication in those patients diagnosed with COVID-19. Diabetes and diabetes-related complications in COVID-19 patients are primarily due to the acute illness caused during the SARS-CoV-2 infection followed by the release of glucocorticoids, catecholamines, and pro-inflammatory cytokines, which have been shown to drive hyperglycemia positively. This review provides brief insights into the potential mechanisms linking COVID-19 and diabetes, and presents clinical management recommendations for better handling of the disease.

3.
Vaccines (Basel) ; 10(10)2022 Oct 19.
Article in English | MEDLINE | ID: mdl-36298616

ABSTRACT

The incidence and death toll due to SARS-CoV-2 infection varied time-to-time; and depended on several factors, including severity (viral load), immune status, age, gender, vaccination status, and presence of comorbidities. The RNA genome of SARS-CoV-2 has mutated and produced several variants, which were classified by the SARS-CoV-2 Interagency Group (SIG) into four major categories. The first category; "Variant Being Monitored (VBM)", consists of Alpha (B.1.1.7), Beta (B.1.351), Gamma (P.1), Delta (B.1.617.2), Epsilon (B.1.427, B.1.429), Eta (B.1.525), Iota (B.1.526), Kappa (B.1.617.1), Mu (B.1.621), and Zeta (P.2); the second category; "Variants of Concern" consists of Omicron (B.1.1.529). The third and fourth categories include "Variants of Interest (VOI)", and "Variants of High Consequence (VOHC)", respectively, and contain no variants classified currently under these categories. The surge in VBM and VOC poses a significant threat to public health globally as they exhibit altered virulence, transmissibility, diagnostic or therapeutic escape, and the ability to evade the host immune response. Studies have shown that certain mutations increase the infectivity and pathogenicity of the virus as demonstrated in the case of SARS-CoV-2, the Omicron variant. It is reported that the Omicron variant has >60 mutations with at least 30 mutations in the Spike protein ("S" protein) and 15 mutations in the receptor-binding domain (RBD), resulting in rapid attachment to target cells and immune evasion. The spread of VBM and VOCs has affected the actual protective efficacy of the first-generation vaccines (ChAdOx1, Ad26.COV2.S, NVX-CoV2373, BNT162b2). Currently, the data on the effectiveness of existing vaccines against newer variants of SARS-CoV-2 are very scanty; hence additional studies are immediately warranted. To this end, recent studies have initiated investigations to elucidate the structural features of crucial proteins of SARS-CoV-2 variants and their involvement in pathogenesis. In addition, intense research is in progress to develop better preventive and therapeutic strategies to halt the spread of COVID-19 caused by variants. This review summarizes the structure and life cycle of SARS-CoV-2, provides background information on several variants of SARS-CoV-2 and mutations associated with these variants, and reviews recent studies on the safety and efficacy of major vaccines/vaccine candidates approved against SARS-CoV-2, and its variants.

4.
Vaccines (Basel) ; 10(7)2022 Jul 15.
Article in English | MEDLINE | ID: mdl-35891289

ABSTRACT

Vaccines against severe acute respiratory syndrome-corona virus-2 (SARS-CoV-2) infection, which causes coronavirus disease-19 (COVID-19) in humans, have been developed and are being tested for safety and efficacy. We conducted the cross-sectional prospective cohort study on 820 patients who were positive for SARS-CoV-2 and were admitted to Princess Krishnajammanni trauma care centre (PKTCC), Mysore, which was converted to a designated COVID hospital between April 2021 to July 2021. After obtaining the informed consent, RT-PCR report, vaccination certificate and patient history, patients were classified according to their vaccination status. Results from the study showed decreases in serum ferritin levels, clinical symptoms, improvement in oxygen saturation, early recovery in patients having diabetes and hypertension, and a substantial reduction in the overall duration of hospital stay in vaccinated patients compared to unvaccinated patients. Further, fully vaccinated patients showed better outcomes compared to single dose vaccinated and nonvaccinated patients. Taken together, our findings reaffirm the vaccine's effectiveness in reducing case fatality and promoting faster recovery compared to nonvaccinated patients. Efforts to increase the number of immunized subjects in the community help to achieve herd immunity and offer protection against the severity of COVID-19 and associated complications while minimizing the public health and economic burden.

5.
Curr Med Chem ; 29(20): 3601-3621, 2022.
Article in English | MEDLINE | ID: mdl-35232337

ABSTRACT

BACKGROUND: Mortality of the older adult population suffering from COVID-19 has been increasing at an alarming rate, and people older than 76 years of age reported 18% mortality. Mainly, the EU and USA exhibited a greater fatality rate due to lack of selective immunization and anti-SARS Co-V-2 therapeutics. Very limited reports are available to delineate the impact of COVID-19 on the geriatric population and the failures of aminoquinoline therapy. METHODS: We performed a substantial literature review in the PubMed/Medline databases to extract the information pertaining to the COVID-19 impact on the geriatric population and recent failures of aminoquinoline therapy in COVID-19 patients of EU, China, USA and the requirement of vaccination. RESULTS AND DISCUSSIONS: Both parental strains and mutant variants of SARS Co-V-2 can induce severe respiratory complications, multiorgan failure, and clotting abnormalities in older adults due to low immunocompetence. Aminoquinoline derivatives, such as chloroquine (CQ) and hydroxychloroquine (HCQ), are preferred primarily for COVID-19 treatment, but several controversies are being reported for its usage worldwide. In this review, we have provided the effects of COVID-19 on the geriatric population of EU and an overview of the mechanism of action of aminoquinolines. Furthermore, CQ and HCQ are not the preferred choice of drugs if the COVID-19 patients already have existing co-morbid conditions viz., diabetes mellitus and hypertension. CONCLUSION: A new advent of COVID-19 vaccines, such as nucleic acid-based (DNA/mRNA) vaccines, protein subunit vaccines, viral vector vaccines, and inactivated vaccines, have been developed for treating SARS-CoV-2 infection after the failure of aminoquinoline therapy in EU, China, and USA patients. However, some of the vaccines are yet to be examined against mutant strains of SARS CoV-2 that originated in the UK, Nigeria, South Africa, Brazil, and India.


Subject(s)
COVID-19 Drug Treatment , COVID-19 , Vaccines , Aged , Antiviral Agents/pharmacology , Antiviral Agents/therapeutic use , COVID-19/prevention & control , COVID-19 Vaccines , Chloroquine/pharmacology , Chloroquine/therapeutic use , Humans , Hydroxychloroquine/therapeutic use , SARS-CoV-2
6.
Curr Med Chem ; 28(39): 8203-8236, 2021.
Article in English | MEDLINE | ID: mdl-34303328

ABSTRACT

Tumor associated macrophages (TAMs), located in the tumor microenvironment (TME), play a significant role in cancer cell survival and progression. TAMs have been involved in producing immuno-suppressive TME in the tumor by generating inflammatory mediators, growth factors, cytokines, chemokines, etc. TAMs can influence the angiogenesis, metastatic behavior of tumor cells (TCs) and cause multidrug resistance. TAMs within the TME can enhance cancer cell metastasis and are stromal and perivascular. The angiogenesis is promoted at the hypoxia, and the avascular zones of TME. Differentiation states of TAMs are considered 'plastic' as they exhibit temporal expression of one or several phenotypes depending on local cues. Emerging cancer research depicted the epigenetic regulation of macrophage polarization (both M1s, M2s) and their potential implications to develop pharmacologic modulators and microRNAs to act as molecular switches and even to serve as targeted therapies to inhibit tumor growth. In the present article, the role of TAMs in tumor progression, angiogenesis and metastasis was discussed. In addition, key signaling cascades regulated by TAMs, which have a role in chemoresistance, were also discussed. Currently, novel pleiotropic properties of various anticancer phytomedicines are gaining importance as they assist in overcoming TAMs-induced chemoresistance. Moreover, these phytomedicines are being tested as 'adjunct therapeutics' along with chemotherapeutic agents, anti-angiogenic molecules, anti-metastatic compounds, and other immune-checkpoint blockers against tumor metastasis/angiogenesis. Hence, a brief note on natural products targeting TAMs was provided. In summary, this review would benefit pharmacologists and medical professionals to develop therapies to target TAMs using multi-OMICs approaches, including genomics, epigenomics, transcriptomics, and proteomics.


Subject(s)
Neoplasms , Tumor-Associated Macrophages , Drug Resistance, Neoplasm , Epigenesis, Genetic , Humans , Macrophages , Neoplasms/drug therapy , Neovascularization, Pathologic/drug therapy , Tumor Microenvironment
7.
Biomed Res Int ; 2021: 8160860, 2021.
Article in English | MEDLINE | ID: mdl-34159203

ABSTRACT

Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection causes coronavirus disease-19 (COVID-19), which is characterized by clinical manifestations such as pneumonia, lymphopenia, severe acute respiratory distress, and cytokine storm. S glycoprotein of SARS-CoV-2 binds to angiotensin-converting enzyme II (ACE-II) to enter into the lungs through membrane proteases consequently inflicting the extensive viral load through rapid replication mechanisms. Despite several research efforts, challenges in COVID-19 management still persist at various levels that include (a) availability of a low cost and rapid self-screening test, (b) lack of an effective vaccine which works against multiple variants of SARS-CoV-2, and (c) lack of a potent drug that can reduce the complications of COVID-19. The development of vaccines against SARS-CoV-2 is a complicated process due to the emergence of mutant variants with greater virulence and their ability to invoke intricate lung pathophysiology. Moreover, the lack of a thorough understanding about the virus transmission mechanisms and complete pathogenesis of SARS-CoV-2 is making it hard for medical scientists to develop a better strategy to prevent the spread of the virus and design a clinically viable vaccine to protect individuals from being infected. A recent report has tested the hypothesis of T cell immunity and found effective when compared to the antibody response in agammaglobulinemic patients. Understanding SARS-CoV-2-induced changes such as "Th-2 immunopathological variations, mononuclear cell & eosinophil infiltration of the lung and antibody-dependent enhancement (ADE)" in COVID-19 patients provides key insights to develop potential therapeutic interventions for immediate clinical management. Therefore, in this review, we have described the details of rapid detection methods of SARS-CoV-2 using molecular and serological tests and addressed different therapeutic modalities used for the treatment of COVID-19 patients. In addition, the current challenges against the development of vaccines for SARS-CoV-2 are also briefly described in this article.


Subject(s)
COVID-19 Drug Treatment , COVID-19 Vaccines/immunology , COVID-19/diagnosis , SARS-CoV-2/immunology , COVID-19/immunology , COVID-19/prevention & control , Drug Development , Humans , Lung/drug effects , Lung/pathology , Lung/virology , Pharmaceutical Preparations/administration & dosage , Viral Load
8.
Can J Physiol Pharmacol ; 96(8): 728-741, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29558627

ABSTRACT

Apoptotic hepatocytes release factors that activate hepatic stellate cells (HSCs), thereby inducing hepatic fibrosis. In the present study, in vivo and in vitro injury models were established using acetaminophen, ethanol, carbon tetrachloride, or thioacetamide. Histology of hepatotoxicant-induced diseased hepatic tissue correlated with differential expression of fibrosis-related genes. A marked increase in co-staining of transforming growth factor ß receptor type II (TGFRIIß) - desmin or α-smooth muscle actin - platelet-derived growth factor receptor ß (PDGFRß), markers of activated HSCs, in liver sections of these hepatotoxicant-treated mice also depicted an increase in Annexin V - cytokeratin expressing hepatocytes. To understand the molecular mechanisms of disease pathology, in vitro experiments were designed using the conditioned medium (CM) of hepatotoxicant-treated HepG2 cells supplemented to HSCs. A significant increase in HSC proliferation, migration, and expression of fibrosis-related genes and protein was observed, thereby suggesting the characteristics of an activated phenotype. Treating HepG2 cells with hepatotoxicants resulted in a significant increase in mRNA expression of platelet-derived growth factor BB (PDGF-BB) and transforming growth factor ß (TGFß). CM supplemented to HSCs resulted in increased phosphorylation of PDGFRß and TGFRIIß along with its downstream effectors, extracellular signal-related kinase 1/2 and focal adhesion kinase. Neutralizing antibodies against PDGF-BB and TGFß effectively perturbed the hepatotoxicant-treated HepG2 cell CM-induced activation of HSCs. This study suggests PDGF-BB and TGFß as potential molecular targets for developing anti-fibrotic therapeutics.


Subject(s)
Hepatic Stellate Cells/metabolism , Hepatic Stellate Cells/pathology , Liver/injuries , Proto-Oncogene Proteins c-sis/metabolism , Transforming Growth Factor beta/metabolism , Animals , Apoptosis/drug effects , Becaplermin , Body Weight/drug effects , Cell Transdifferentiation/drug effects , Culture Media, Conditioned/pharmacology , Female , Fibrosis , Gene Expression Regulation/drug effects , Hep G2 Cells , Hepatic Stellate Cells/drug effects , Humans , Lipid Peroxidation/drug effects , Liver/pathology , Male , Mice, Inbred C57BL , Neutralization Tests , Organ Size/drug effects , Oxidative Stress/drug effects , Signal Transduction/drug effects
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