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1.
Rev Sci Instrum ; 95(5)2024 May 01.
Article En | MEDLINE | ID: mdl-38717270

An efficient and compact, 20 kW solid-state power amplifier (SSA) at 325 MHz has been designed and developed in-house, using single stage combining. It comprises of 24 nos. of 1 kW power amplifier (PA) modules, a 24-way Wilkinson power combiner and divider, and other peripheral systems. The typical gain and conversion efficiency of the PA modules at 1.0 kW output is 21.7 dB and 66.6%, respectively. It is demonstrated that overall power gain and AC to RF efficiency of this SSA at 20 kW is 88.5 dB and 54.8%, respectively, which matches closely with the design estimates. The harmonic content in the RF output is < -40 dBc for all the harmonics. The results of the Monte Carlo simulation are also presented, showing lower bound on combining efficiency with a degree of confidence if magnitude and phase data for 24 inputs are randomly chosen from a normal distribution's pre-defined interval. The salient features of this SSA include power density of 12.7 kW/m3, AC to RF efficiency of 54.8% at 20 kW, and guaranteed output of 20 kW with one failed PA module and 18.1 kW under two failed PA modules condition.

2.
Nanoscale Adv ; 6(9): 2469-2486, 2024 Apr 30.
Article En | MEDLINE | ID: mdl-38694466

Neuronal loss in Alzheimer's disease has been reported to display features of apoptosis, pyroptosis (programmed necrosis), or necroptosis. This study thoroughly examines the production and characterization of MCM-41 based berberine (BBR)-loaded porous silica nanoparticles (MSNs) by a modified Stöber method, focusing on their possible role in inhibiting the apoptotic process. Particle size, polydispersity index, morphology, drug loading, zeta potential, entrapment efficiency, and drug release were examined. The formulation was analyzed using various spectroscopic techniques. The surface area was computed by the Brunauer-Emmett-Teller plot. Computational models were developed for molecular dynamics simulation studies. A small PDI value indicated an even distribution of particles at nanoscale sizes (80-100 nm). Results from XRD and SEAD experiments confirmed the amorphous nature of BBR in nanoparticles. Nanoparticles had high entrapment (75.21 ± 1.55%) and drug loading (28.16 ± 2.5%) efficiencies. A negative zeta potential value (-36.861.1 mV) indicates the presence of silanol groups on the surface of silica. AFM findings reveal bumps due to the surface drug that contributed to the improved roughness of the MSNs-BBR surface. Thermal gravimetric analysis confirmed the presence of BBR in MSNs. Drug release was controlled by simple diffusion or quasi-diffusion. Molecular dynamics simulations confirmed the existence of diffused drug molecules. Cellular studies using SH-SY-5Y cells revealed dose-dependent growth inhibition. Fragmented cell nuclei and nuclear apoptotic bodies in DAPI-stained cells exposed to nanoparticles showed an increase in apoptotic cells. Flow cytometry analysis demonstrated a lower red-to-green ratio in SH-SY-5Y cells treated with nanoparticles. This suggests improved mitochondrial health, cellular viability restoration, and prevention of the apoptotic process. This study provides essential data on the synthesis and potential of MSNs loaded with BBR, which may serve as a viable therapeutic intervention for conditions associated with apoptosis.

4.
Int Urol Nephrol ; 56(3): 1071-1081, 2024 Mar.
Article En | MEDLINE | ID: mdl-37615844

PURPOSE: Endothelial injury, involved in the pathogenesis of renal fibrosis, can generate microparticles (MPs). These are 0.1-1 µm membrane-bound vesicles shed from the damaged or activated cell surfaces. We analyzed the presence of circulating MPs and EnMPs in IgAN and correlated with markers of endothelial injury and disease activity. METHODS: The study included 30 IgAN (mean age 31.5 ± 9 years), 25 healthy controls and Lupus nephritis (n = 10) as disease controls. Circulating MPs were quantitated by Flow cytometry and EnMPs were analyzed using anti-CD31-FITC and anti-CD146-PE antibodies. Their levels were correlated with serum von Willebrand Factor, histological Oxford MEST-C score and renal outcome. A prospective validation group of 20 patients of biopsy-proven IgA nephropathy was also included. RESULTS: IgAN had significantly higher levels of MPs, EnMPs and vWF compared to controls. On multivariate analysis, plasma levels of total MPs, EnMPs and serum vWF correlated significantly with the presence of hypertension and E1 on histology. E1 and high MPs (> 130 counts/µl) were associated with shorter time to doubling of serum creatinine. MPs cutoff level of 130 counts/µl had a sensitivity of 75%, specificity of 93.3% and diagnostic accuracy of 89.5% for E1 in the validation cohort. CONCLUSION: Circulating MPs and EnMPs in IgAN correlate with E1 on histology and have a potential as non-invasive biomarkers to predict disease activity and renal outcome.


Glomerulonephritis, IGA , Humans , Young Adult , Adult , Glomerulonephritis, IGA/pathology , Prognosis , von Willebrand Factor/analysis , Kidney/pathology , Biomarkers
5.
Artif Cells Nanomed Biotechnol ; 52(1): 46-58, 2024 Dec.
Article En | MEDLINE | ID: mdl-38156875

Novel magnetic and metallic nanoparticles garner much attention of researchers due to their biological, chemical and catalytic properties in many chemical reactions. In this study, we have successfully prepared a core-shell Fe3O4@SiO2@PDA nanocomposite wrapped with Ag using a simple synthesis method, characterised and tested on small cell lung cancer and antibacterial strains. Incorporating Ag in Fe3O4@SiO2@PDA provides promising advantages in biomedical applications. The magnetic Fe3O4 nanoparticles were coated with SiO2 to obtain negatively charged surface which is then coated with polydopamine (PDA). Then silver nanoparticles were assembled on Fe3O4@SiO2@PDA surface, which results in the formation core-shell nanocomposite. The synthesised nanocomposite were characterized using SEM-EDAX, dynamic light scattering, XRD, FT-IR and TEM. In this work, we report the anticancer activity of silver nanoparticles against H1299 lung cancer cell line using MTT assay. The cytotoxicity data revealed that the IC50 of Fe3O4@SiO2@PDA@Ag against H1299 lung cancer nanocomposites cells was 21.52 µg/mL. Furthermore, the biological data of nanocomposites against Gram-negative 'Pseudomonas aeruginosa' and Gram-positive 'Staphylococcus aureus' were carried out. The range of minimum inhibitory concentration was found to be 115 µg/mL where gentamicin was used as a standard drug. The synthesized AgNPs proves its supremacy as an efficient biomedical agent and AgNPs may act as potential beneficial molecule in lung cancer chemoprevention and antibacterial strains.


In the present study, we have successfully prepared a core-shell Fe3O4@SiO2@PDA@Ag nanocomposite.We have investigated the dose-dependent cellular toxicity of silver nanocomposite in the nonsmall cell lung cancer cell line H1299 using MTT assay.Also, we have evaluated the mode of cell death using apoptosis.We have also evaluated the bioactivity of AgNPs on both Gram-positive and Gram-negative bacterial cells with highly efficient antibacterial potency.


Lung Neoplasms , Metal Nanoparticles , Nanocomposites , Humans , Silver/pharmacology , Silver/chemistry , Silicon Dioxide/chemistry , Metal Nanoparticles/chemistry , Lung Neoplasms/drug therapy , Spectroscopy, Fourier Transform Infrared , Anti-Bacterial Agents/chemistry , Nanocomposites/chemistry , Cell Line
6.
Environ Toxicol Pharmacol ; 106: 104356, 2024 Mar.
Article En | MEDLINE | ID: mdl-38158029

Contamination of drinking water due to fluoride (F-) is a major concern worldwide. Although fluoride is an essential trace element required for humans, it has severe human health implications if levels exceed 1.5 mg. L-1 in groundwater. Several treatment technologies have been adopted to remove fluoride and reduce the exposure risk. The present article highlights the source, geochemistry, spatial distribution, and health implications of high fluoride in groundwater. Also, it discusses the underlying mechanisms and controlling factors of fluoride contamination. The problem of fluoride-contaminated water is more severe in India's arid and semiarid regions than in other Asian countries. Treatment technologies like adsorption, ion exchange, precipitation, electrolysis, electrocoagulation, nanofiltration, coagulation-precipitation, and bioremediation have been summarized along with case studies to look for suitable technology for fluoride exposure reduction. Although present technologies are efficient enough to remove fluoride, they have specific limitations regarding cost, labour intensity, and regeneration requirements.


Drinking Water , Groundwater , Water Pollutants, Chemical , Humans , Fluorides/analysis , Environmental Monitoring , Water Pollutants, Chemical/analysis , Drinking Water/analysis
7.
Expert Opin Drug Deliv ; 20(12): 1839-1857, 2023.
Article En | MEDLINE | ID: mdl-38100459

INTRODUCTION: The efficiency of brain therapeutics is greatly hindered by the blood-brain barrier (BBB). BBB's protective function, selective permeability, and dynamic functionality maintain the harmony between the brain and peripheral region. Thus, the design of any novel drug carrier system requires the complete study and investigation of BBB permeability, efflux transport, and the effect of associated cellular and non-vascular unit trafficking on BBB penetrability. The in vitro BBB models offer a most promising, and reliable mode of initial investigation of BBB permeability and associated factors as strong evidence for further preclinical and clinical investigation. AREA COVERED: This review work covers the structure and functions of BBB components and different types of in vitro BBB models along with factors affecting BBB model development and model selection criteria. EXPERT OPINION: In vivo models assume to reciprocate the physiological environment to the maximum extent. However, the interspecies variability, NVUs trafficking, dynamic behavior of BBB, etc., lead to non-reproducible results. The in vitro models are comparatively less complex, and flexible, as per the study design, could generate substantial evidence and help identify suitable in vivo animal model selection.


Blood-Brain Barrier , Brain , Animals , Biological Transport , Endothelial Cells , Permeability
8.
Environ Sci Pollut Res Int ; 30(50): 108347-108369, 2023 Oct.
Article En | MEDLINE | ID: mdl-37755596

Pesticides play a critical role in terms of agricultural output nowadays. On top of that, pesticides provide economic support to our farmers. However, the usage of pesticides has created a public health issue and environmental hazard. Chlorpyrifos (CPY), an organophosphate pesticide, is extensively applied as an insecticide, acaricide, and termiticide against pests in various applications. Environmental pollution has occurred because of the widespread usage of CPY, harming several ecosystems, including soil, sediment, water, air, and biogeochemical cycles. While residual levels in soil, water, vegetables, foodstuffs, and human fluids have been discovered, CPY has also been found in the sediment, soil, and water. The irrefutable pieces of evidence indicate that CPY exposure inhibits the choline esterase enzyme, which impairs the ability of the body to use choline. As a result, neurological, immunological, and psychological consequences are seen in people and the natural environment. Several research studies have been conducted worldwide to identify and develop CPY remediation approaches and its derivatives from the environment. Currently, many detoxification methods are available for pesticides, such as CPY. However, recent research has shown that the breakdown of CPY using bacteria is the most proficient, cost-effective, and sustainable. This current article aims to outline relevant research events, summarize the possible breakdown of CPY into various compounds, and discuss analytical summaries of current research findings on bacterial degradation of CPY and the potential degradation mechanism.


Chlorpyrifos , Insecticides , Pesticides , Humans , Chlorpyrifos/chemistry , Organophosphorus Compounds , Ecosystem , Insecticides/chemistry , Soil , Choline , Water
9.
Biomacromolecules ; 24(11): 4798-4818, 2023 11 13.
Article En | MEDLINE | ID: mdl-37729507

Organic transformations mediated by visible light have gained popularity in recent years as they are green, renewable, inexpensive, and clean and yield excellent products. The present study describes cyclo-condensation of 2-methylthiazole-4-carbothioamide with differently substituted α-bromo-1,3-diketones achieved by utilizing a white light-emitting diode (LED) (9W) to accomplish the regioselective synthesis of novel 5-aroyl/hetaroyl-2',4-dimethyl-2,4'-bithiazole derivatives as DNA/bovine serum albumin (BSA)-targeting agents. The structure characterization of the exact regioisomer was achieved unequivocally by heteronuclear two-dimensional nuclear magnetic resonance (2D-NMR) spectroscopy [1H-13C] HMBC; [1H-13C] HMQC; and [1H-15N] HMBC. In silico toxicity studies indicated that the synthesized compounds exhibit low toxicity risks and adhere to the rules of oral bioavailability without any exception. Computational molecular modeling of the bithiazole derivatives with the dodecamer sequence of the DNA duplex and BSA identified 5-(4-chlorobenzoyl)-2',4-dimethyl-2,4'-bithiazole 7g as the most suitable derivative that can interact effectively with these biomolecules. Furthermore, theoretical results concurred with the ex vivo binding mode of the 7g with calf thymus DNA (ct-DNA) and BSA through a variety of spectroscopic techniques, viz., ultraviolet-visible (UV-visible), circular dichroism (CD), steady-state fluorescence, and competitive displacement assay, along with viscosity measurements.


DNA , Serum Albumin, Bovine , Binding Sites , Serum Albumin, Bovine/chemistry , Molecular Docking Simulation , Spectrometry, Fluorescence , Protein Binding , DNA/chemistry , Circular Dichroism , Thermodynamics , Spectrophotometry, Ultraviolet
10.
RSC Med Chem ; 14(7): 1344-1350, 2023 Jul 20.
Article En | MEDLINE | ID: mdl-37484568

Visceral leishmaniasis is a neglected protozoan disease with high mortality. Existing treatments exhibit a number of limitations, resulting in a significant challenge for public health, especially in developing countries in which the disease is endemic. With a limited pipeline of potential drugs in clinical trials, natural products could offer an attractive source of new pharmaceutical prototypes, not least due to their high chemodiversity. In the present work, a study of anti-L. (L.) infantum potential was carried out for a series of 39 synthetic compounds based on the core scaffold of the neolignan dehydrodieugenol B. Of these, 14 compounds exhibited activity against intracellular amastigotes, with 50% inhibitory concentration (IC50) values between 3.0 and 32.7 µM. A structure-activity relationship (SAR) analysis demonstrated a requirement for polar functionalities to improve activity. Lacking mammalian cytotoxicity and presenting the highest potency against the clinically relevant form of the parasite, compound 24 emerged as the most promising, fulfilling the hit criteria for visceral leishmaniasis defined by the Drugs for Neglected Diseases initiative (DNDi). This study emphasizes the potential of dehydrodieugenol B analogues as new candidates for the treatment of visceral leishmaniasis and suggests 24 to be a suitable compound for future optimization, including mechanism of action and pharmacokinetic studies.

11.
Indian J Otolaryngol Head Neck Surg ; 75(2): 917-920, 2023 Jun.
Article En | MEDLINE | ID: mdl-37275043

We report 2 vocal fold aspergillosis cases from Otolaryngology department of a tertiary hospital, Bhubaneswar. A 26 years old female visited the OPD with chief complaint of progressive hoarseness and pain while talking since 6 months. While another 29 years old female complained of having progressive hoarseness since 4 months preceded by an episode of sore throat. Both cases had microlaryngeal surgery/ endo laryngeal surgery followed by excisional biopsy.

12.
J Maxillofac Oral Surg ; 22(2): 344-351, 2023 Jun.
Article En | MEDLINE | ID: mdl-37122785

Aim: To provide a concise review on risk factors, stages, pathophysiology, prevention and possible treatment options for both MRONJ and ORN individually. Methods: The review was conducted according to the 'Preferred Reporting Items for Systematic Reviews and Meta-Analyses' (PRISMA) guidelines. A comprehensive search of the PUBMED, Ebsco, SCOPUS, WEB OF SCIENCE and NDH for articles published up until 2021 was performed. After screening and full text analyses, 44 studies were included in this review. Definition, risk factors, etiology, symptoms, stages, pathophysiology, prevention and possible management options were explored and highlighted in this article. Results: Three studies described osteonecrosis of jaw (ONJ) in general, 15 studies described ONJ associated with radiotherapy and 26 studies described ONJ associated with medications. Both the two conditions (ORN) and (MRONJ) have relatively similar clinical presentations clearing the fact that a resemblance in clinical presentations does not necessarily denote a similar pathophysiology. Conclusion: However, various advancements have been made in the control and management of ONJ, but until and unless need for high tumoricidal doses exists, ONJ will certainly continue to remain as a clinical challenge demanding satisfactory treatment to improve the quality of life of the patient.

13.
Semin Liver Dis ; 43(2): 163-175, 2023 05.
Article En | MEDLINE | ID: mdl-37225145

Drug-induced liver injury (DILI) is a rare but severe adverse drug reaction seen in pharmacotherapy and a major cause of postmarketing drug withdrawals. Advances in genome-wide studies indicate that genetic and epigenetic diversity can lead to inter-individual differences in drug response and toxicity. It is necessary to identify how the genetic variations, in the presence of environmental factors, can contribute to development and progression of DILI. Studies on microRNA, histone modification, DNA methylation, and single nucleotide polymorphisms related to DILI were retrieved from databases and were analyzed for the current research and updated to develop this narrative review. We have compiled some of the major genetic, epigenetic, and pharmacogenetic factors leading to DILI. Many validated genetic risk factors of DILI, such as variants of drug-metabolizing enzymes, HLA alleles, and some transporters were identified. In conclusion, these studies provide useful information in risk alleles identification and on implementation of personalized medicine.


Chemical and Drug Induced Liver Injury , Humans , Chemical and Drug Induced Liver Injury/genetics , Alleles , Polymorphism, Single Nucleotide , Epigenesis, Genetic , Risk Factors
14.
Bioorg Chem ; 136: 106524, 2023 07.
Article En | MEDLINE | ID: mdl-37079989

A series of twenty novel (E)-arylidene-hydrazinyl-thiazole derivatives has been synthesized employing α-bromo-ß-diketones, thiosemicarbazide, and aromatic/heteroaromatic aldehydes with a simple and facile one-pot multicomponent reaction passageway. This organic transformation proceeds efficiently in aqueous media and demonstrated a large functional group tolerance. The structures and stereochemistry of the regioisomeric product were rigorously characterized using heteronuclear 2D NMR experiments. The binding potential of the synthesized analogs with B-DNA dodecamer d(CGCGAATTCGCG)2 was primarily screened using molecular modeling tools and further, mechanistic investigations (either groove or intercalation) were performed using various spectroscopic techniques such as UV-Visible, Fluorescence, and Circular dichroism. The absorption spectra showed a hyperchromic shift in the absorption maxima of ctDNA with successive addition of thiazole derivatives, implying groove binding mode of interactions, further supported by displacement assay and circular dichroism analysis. Furthermore, steady-state fluorescence analysis revealed the static mode of quenching and moderate bindings between the ligand and DNA biomolecule. The competitive studies showed that the derivatives having a pyridinyl (heteroaromatic) group in their structure, bind with the nucleic acid of calf-thymus (ctDNA) more effectively in the minor groove region as compared with the aromatic substitutions.


DNA , Thermodynamics , Nucleic Acid Conformation , DNA/chemistry , Models, Molecular , Circular Dichroism , Spectrometry, Fluorescence , Molecular Docking Simulation
15.
Toxicol Appl Pharmacol ; 466: 116449, 2023 05 01.
Article En | MEDLINE | ID: mdl-36924898

Intensive and inefficient exploitation of pesticides through modernized agricultural practices has caused severe pesticide contamination problems to the environment and become a crucial problem over a few decades. Due to their highly toxic and persistent properties, they affect and get accumulated in non-target organisms, including microbes, algae, invertebrates, plants as well as humans, and cause severe issues. Considering pesticide problems as a significant issue, researchers have investigated several approaches to rectify the pesticide contamination problems. Several analyses have provided an extensive discussion on pesticide degradation but using specific technology for specific pesticides. However, in the middle of this time, cleaner techniques are essential for reducing pesticide contamination problems safely and environmentally friendly. As per the research findings, no single research finding provides concrete discussion on cleaner tactics for the remediation of contaminated sites. Therefore, in this review paper, we have critically discussed cleaner options for dealing with pesticide contamination problems as well as their advantages and disadvantages have also been reviewed. As evident from the literature, microbial remediation, phytoremediation, composting, and photocatalytic degradation methods are efficient and sustainable and can be used for treatment at a large scale in engineered systems and in situ. However, more study on the bio-integrated system is required which may be more effective than existing technologies.


Pesticides , Humans , Pesticides/metabolism , Agriculture , Biodegradation, Environmental , Technology
16.
ACS Omega ; 7(47): 43290-43305, 2022 Nov 29.
Article En | MEDLINE | ID: mdl-36467923

Selective permeability of the blood-brain barrier restricts the treatment efficacy of neurologic diseases. Berberine (BBR) and curcumin (CUR)-loaded transferosomes (TRANS) were prepared for the effective management of Alzheimer's disease (AD). The study involved the syntheses of BBR-TRANS, CUR-TRANS, and BBR-CUR-TRANS by the film hydration method. Vesicles were characterized to ensure the formation of drug-loaded vesicles and their in vivo performance. The particle sizes of BBR-TRANS, CUR-TRANS, and BBR-CUR-TRANS were 139.2 ± 7, 143.4 ± 8, and 165.3 ± 6.5 nm, respectively. The presence of diffused rings in the SED image indicates the crystalline nature of the payload. Low surface roughness in an AFM image could be associated with the presence of a surface lipid. BBR-CUR-TRANS showed 41.03 ± 1.22 and 47.79 ± 3.67% release of BBR and 19.22 ± 1.47 and 24.67 ± 1.94% release of CUR, respectively, in phosphate buffer saline (pH 7.4) and acetate buffer (pH 4.0). Formulations showed sustained release of both loaded drugs. BBR-TRANS, CUR-TRANS, and BBR-CUR-TRANS exhibited a lower percentage of hemolysis than pure BBR and CUR, indicating the safety of the payload from delivery vesicles. Lower percentages of binding were recorded from BBR-CUR-TRANS than BBR-TRANS and CUR-TRANS. Acetylcholinesterase inhibition activity of the prepared transferosomes was greater than that of pure drugs, which are thought to have good cellular penetration. The spatial memory was improved in treated mice models. The level of malondialdehyde decreased in AD animals treated with BBR-TRANS, CUR-TRANS, and BBR-CUR-TRANS, respectively, as compared to the scopolamine-induced AD animals. BBR-CUR-TRANS-treated animals showed the highest decrease in the NO level. The catalase level was significantly restored in scopolamine-intoxicated animals treated with BBR-TRANS, CUR-TRANS, and BBR-CUR-TRANS. The immunohistochemistry result suggested that the BBR-TRANS, CUR-TRANS, and BBR-CUR-TRANS have significantly decreased the regulation of expression of BACE-1 through antioxidant activity. In conclusion, the study highlights the utility of formulated transferosomes as promising carriers for the co-delivery of drugs to the brain.

17.
J Family Med Prim Care ; 11(8): 4330-4341, 2022 Aug.
Article En | MEDLINE | ID: mdl-36352911

The reasons for high morbidity and mortality with Corona virus disease (COVID-19) disease remain unanswered with extremes of manifestation and uncertainty of modes of transmission for which biomarkers are urgently needed for early prediction of severity and prompt treatment. We have reviewed publications from PubMed (years 2019-2021) analysing the biochemical, immune-inflammatory, nucleic acid, and cellular biomarkers that predict infection, disease progression in COVID-19 with emphasis on organ-specific damage. Our analysis of 65 biomarkers assessing the impact of SCoV-2 infection on five organs (lung, liver, cardiac, kidney, and neural) reported that increased levels of CRP, TNF-α, ferritin, IL-6, D-dimer, Procalcitonin, Fibrinogen to Albumin Ratio (FAR), and decrease platelet count (PC), lymphocyte count, leukocyte count, and CD4+/CD8 + ratio shows promising association in the early diagnosis, prediction of prognosis and severity disease and also correlates with cytokine storm a cardinal feature of COVID-19 progression. In the above scenario, this review has put forth the most promising biomarkers for COVID diagnosis and prognosis based on the reported literature. In recent year's chemically synthesized antibody-like biomolecules, aptamers were also used in the diagnosis of COVID-19 which could be preferably used for diagnosis over antibodies. Biomarkers including increase in free DNA and Fibrinogen-to-Albumin Ratio, CRP, PCT, and Ferritin along with a consequential decrease of CD3+ T, CD4+ T, CD8+ T, NK cells with corresponding increase in CD4+/CD8+ ratio following SARS CoV-2 infection has been consistently correlated with disease severity. Despite the two waves of COVID-19 pandemic, currently there is no standard clinical practice guideline for evaluating the severity of the devastating pandemic of COVID-19, hence these biomarkers will have immense relevance for the third and subsequent wave of COVID-19 and related pandemic.

18.
Oxid Med Cell Longev ; 2022: 3012778, 2022.
Article En | MEDLINE | ID: mdl-36092161

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a human coronavirus (HCoV) that has created a pandemic situation worldwide as COVID-19. This virus can invade human cells via angiotensin-converting enzyme 2 (ACE2) receptor-based mechanisms, affecting the human respiratory tract. However, several reports of neurological symptoms suggest a neuroinvasive development of coronavirus. SARS-CoV-2 can damage the brain via several routes, along with direct neural cell infection with the coronavirus. The chronic inflammatory reactions surge the brain with proinflammatory elements, damaging the neural cells, causing brain ischemia associated with other health issues. SARS-CoV-2 exhibited neuropsychiatric and neurological manifestations, including cognitive impairment, depression, dizziness, delirium, and disturbed sleep. These symptoms show nervous tissue damage that enhances the occurrence of neurodegenerative disorders and aids dementia. SARS-CoV-2 has been seen in brain necropsy and isolated from the cerebrospinal fluid of COVID-19 patients. The associated inflammatory reaction in some COVID-19 patients has increased proinflammatory cytokines, which have been investigated as a prognostic factor. Therefore, the immunogenic changes observed in Parkinson's and Alzheimer's patients include their pathogenetic role. Inflammatory events have been an important pathophysiological feature of neurodegenerative diseases (NDs) such as Parkinson's and Alzheimer's. The neuroinflammation observed in AD has exacerbated the Aß burden and tau hyperphosphorylation. The resident microglia and other immune cells are responsible for the enhanced burden of Aß and subsequently mediate tau phosphorylation and ultimately disease progression. Similarly, neuroinflammation also plays a key role in the progression of PD. Several studies have demonstrated an interplay between neuroinflammation and pathogenic mechanisms of PD. The dynamic proinflammation stage guides the accumulation of α-synuclein and neurodegenerative progression. Besides, few viruses may have a role as stimulators and generate a cross-autoimmune response for α-synuclein. Hence, neurological complications in patients suffering from COVID-19 cannot be ruled out. In this review article, our primary focus is on discussing the neuroinvasive effect of the SARS-CoV-2 virus, its impact on the blood-brain barrier, and ultimately its impact on the people affected with neurodegenerative disorders such as Parkinson's and Alzheimer's.


Alzheimer Disease , COVID-19 , Parkinson Disease , Alzheimer Disease/complications , COVID-19/complications , Humans , Parkinson Disease/complications , Peptidyl-Dipeptidase A , SARS-CoV-2 , alpha-Synuclein
19.
ACS Med Chem Lett ; 13(8): 1329-1336, 2022 Aug 11.
Article En | MEDLINE | ID: mdl-35978701

A virtual screening approach based on a five-feature pharmacophoric model for negative modulators of GLI1 was applied to databases of commercially available compounds. The resulting quinoline derivatives showed significant ability to reduce the GLI1 protein level and were characterized by submicromolar antiproliferative activity toward human melanoma A375 and medulloblastoma DAOY cell lines. Decoration of the quinoline ring and chemical rigidification to an oxazino-quinoline scaffold allowed us to deduce SAR considerations for future ligand optimization.

20.
Pharmaceutics ; 14(7)2022 Jun 28.
Article En | MEDLINE | ID: mdl-35890267

Malaria elimination urgently needs novel antimalarial therapies that transcend resistance, toxicity, and high costs. Our multicentric international collaborative team focuses on developing multistage antimalarials that exhibit novel mechanisms of action. Here, we describe the design, synthesis, and evaluation of a novel multistage antimalarial compound, 'Calxinin'. A compound that consists of hydroxyethylamine (HEA) and trifluoromethyl-benzyl-piperazine. Calxinin exhibits potent inhibitory activity in the nanomolar range against the asexual blood stages of drug-sensitive (3D7), multidrug-resistant (Dd2), artemisinin-resistant (IPC4912), and fresh Kenyan field isolated Plasmodium falciparum strains. Calxinin treatment resulted in diminished maturation of parasite sexual precursor cells (gametocytes) accompanied by distorted parasite morphology. Further, in vitro liver-stage testing with a mouse model showed reduced parasite load at an IC50 of 79 nM. A single dose (10 mg/kg) of Calxinin resulted in a 30% reduction in parasitemia in mice infected with a chloroquine-resistant strain of the rodent parasite P. berghei. The ex vivo ookinete inhibitory concentration within mosquito gut IC50 was 150 nM. Cellular in vitro toxicity assays in the primary and immortalized human cell lines did not show cytotoxicity. A computational protein target identification pipeline identified a putative P. falciparum membrane protein (Pf3D7_1313500) involved in parasite calcium (Ca2+) homeostasis as a potential Calxinin target. This highly conserved protein is related to the family of transient receptor potential cation channels (TRP-ML). Target validation experiments showed that exposure of parasitized RBCs (pRBCs) to Calxinin induces a rapid release of intracellular Ca2+ from pRBCs; leaving de-calcinated parasites trapped in RBCs. Overall, we demonstrated that Calxinin is a promising antimalarial lead compound with a novel mechanism of action and with potential therapeutic, prophylactic, and transmission-blocking properties against parasites resistant to current antimalarials.

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