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1.
Microsc Res Tech ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38747091

RESUMO

The Au partially embedded nanostructure (PEN) is synthesized by ion irradiation on an Au thin film deposited on a glass substrate using a 50 keV Ar ion. Scanning electron microscopy results show ion beam-induced restructuring from irregularly shaped nanostructures (NSs) to spherical Au NSs, and further ion irradiation leads to the formation of well-separated spherical nanoparticles. Higuchi's algorithm of surface analysis is utilized to find the evolution of surface morphology with ion irradiation in terms of the Hurst exponent and fractal dimension. The Au PEN is evidenced by Rutherford backscattering spectrometry and optical studies. Also, the depth of the mechanism behind synthesized PEN is explained on the basis of theoretical simulations, namely, a unified thermal spike and a Monte Carlo simulation consisting of dynamic compositional changes (TRIDYN). Another set of plasmonic NSs was formed on the surface by thermal annealing of the Au film on the substrate. Glucose sensing has been studied on the two types of plasmonic layers: nanoparticles on the surface and PEN. The results reveal the sensing responses of both types of plasmonic layers. However, PEN retains its plasmonic behavior as the NSs are still present after washing with water, which demonstrates the potential for reusability. RESEARCH HIGHLIGHTS: Synthesis of PENs by ion irradiation Utilization of Higuchi's algorithm to explore the surface morphology. Unified thermal spike and TRIDYN simulations being used to explain the results. Glucose is only used as a test case for reusability of substrate.

2.
Sci Rep ; 14(1): 10975, 2024 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-38744876

RESUMO

Common wheat (Triticum aestivum L.) is a major staple food crop, providing a fifth of food calories and proteins to the world's human population. Despite the impressive growth in global wheat production in recent decades, further increases in grain yield are required to meet future demands. Here we estimated genetic gain and genotype stability for grain yield (GY) and determined the trait associations that contributed uniquely or in combination to increased GY, through a retrospective analysis of top-performing genotypes selected from the elite spring wheat yield trial (ESWYT) evaluated internationally during a 14-year period (2003 to 2016). Fifty-six ESWYT genotypes and four checks were sown under optimally irrigated conditions in three phenotyping trials during three consecutive growing seasons (2018-2019 to 2020-2021) at Norman E. Borlaug Research Station, Ciudad Obregon, Mexico. The mean GY rose from 6.75 (24th ESWYT) to 7.87 t ha-1 (37th ESWYT), representing a cumulative increase of 1.12 t ha-1. The annual genetic gain for GY was estimated at 0.96% (65 kg ha-1 year-1) accompanied by a positive trend in genotype stability over time. The GY progress was mainly associated with increases in biomass (BM), grain filling rate (GFR), total radiation use efficiency (RUE_total), grain weight per spike (GWS), and reduction in days to heading (DTH), which together explained 95.5% of the GY variation. Regression lines over the years showed significant increases of 0.015 kg m-2 year-1 (p < 0.01), 0.074 g m-2 year-1 (p < 0.05), and 0.017 g MJ-1 year-1 (p < 0.001) for BM, GFR, and RUE_total, respectively. Grain weight per spike exhibited a positive but no significant trend (0.014 g year-1, p = 0.07), whereas a negative tendency for DTH was observed (- 0.43 days year-1, p < 0.001). Analysis of the top ten highest-yielding genotypes revealed differential GY-associated trait contributions, demonstrating that improved GY can be attained through different mechanisms and indicating that no single trait criterion is adopted by CIMMYT breeders for developing new superior lines. We conclude that CIMMYT's Bread Wheat Breeding Program has continued to deliver adapted and more productive wheat genotypes to National partners worldwide, mainly driven by enhancing RUE_total and GFR and that future yield increases could be achieved by intercrossing genetically diverse top performer genotypes.


Assuntos
Grão Comestível , Genótipo , Triticum , Triticum/genética , Triticum/crescimento & desenvolvimento , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Fenótipo , Estações do Ano , México
3.
J Org Chem ; 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38727567

RESUMO

An efficient protocol for the synthesis of 2,3-disubstituted phenalenones from para-quinone methides (p-QMs) and acenaphthoquinone is described. The reaction involves P(NMe2)3-mediated [1,2]-phospha-Brook rearrangement followed by Lewis acid-assisted 1,2-carbonyl migration to afford the 2,3-disubstituted phenalenones. The developed protocol tolerates a broad range of substrates to form a variety of phenalenones in good to excellent yields. Moreover, the utility of the synthesized phenalenones is also demonstrated by performing its transformations to other adducts.

4.
Org Biomol Chem ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38717247

RESUMO

A practical and straightforward protocol to access trifluoromethylated/perfluoroalkylated heteroarenes via radical-type nucleophilic substitution rather than typical radical-type electrophilic substitution is described here. The substrate scope was observed to be broad and diverse-covering arenes, heteroarenes (containing N, O, S), bioactive cores, and allylic cores. Mechanistic studies confirmed a radical-mediated reaction pathway.

5.
Nat Prod Res ; : 1-6, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38656916

RESUMO

Fractions were isolated from the leaves extract of Kalanchoe pinnata and subjected to scrutiny for their prospective anti-obesity properties. An array of preliminary phytochemical, invitro antioxidant, and enzyme inhibition assays were executed, which discerned fractions F1 and F2 as the most effective fractions. These fractions were subsequently studied through invivo experiments, affirming that F2 as the most potent fraction. Further characterisation of F2 was conducted via HPTLC-Mass spectrometry (MS-MSn) techniques. The outcomes demonstrated that F2 produced a notable anti-obesity effect in obese mice, reducing their body weight and lipid metrics, and leading to advantageous changes in their organs. An analytical examination of F2 revealed the existence of four principal compounds, which were subsequently subjected to insilico molecular docking and dynamic analysis, confirming their aptitude for binding to selected proteins. These findings imply that the utilisation of Kalanchoe pinnata leaves could provide a promising therapeutic strategy for the treatment of obesity.

6.
Antioxidants (Basel) ; 13(4)2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38671877

RESUMO

Polyphenols, as secondary metabolites ubiquitous in plant sources, have emerged as pivotal bioactive compounds with far-reaching implications for human health. Plant polyphenols exhibit direct or indirect associations with biomolecules capable of modulating diverse physiological pathways. Due to their inherent abundance and structural diversity, polyphenols have garnered substantial attention from both the scientific and clinical communities. The review begins by providing an in-depth analysis of the chemical intricacies of polyphenols, shedding light on their structural diversity and the implications of such diversity on their biological activities. Subsequently, an exploration of the dietary origins of polyphenols elucidates the natural plant-based sources that contribute to their global availability. The discussion extends to the bioavailability and metabolism of polyphenols within the human body, unraveling the complex journey from ingestion to systemic effects. A central focus of the review is dedicated to unravelling the antioxidant effects of polyphenols, highlighting their role in combating oxidative stress and associated health conditions. The comprehensive analysis encompasses their impact on diverse health concerns such as hypertension, allergies, aging, and chronic diseases like heart stroke and diabetes. Insights into the global beneficial effects of polyphenols further underscore their potential as preventive and therapeutic agents. This review article critically examines the multifaceted aspects of dietary polyphenols, encompassing their chemistry, dietary origins, bioavailability/metabolism dynamics, and profound antioxidant effects. The synthesis of information presented herein aims to provide a valuable resource for researchers, clinicians, and health enthusiasts, fostering a deeper understanding of the intricate relationship between polyphenols and human health.

7.
Infect Dis Ther ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609668

RESUMO

Ritonavir is a potent inhibitor of the cytochrome P450 3A4 enzyme and is commonly used as a pharmacokinetic (PK) enhancer in antiviral therapies because it increases bioavailability of concomitantly administered antivirals. Decades of experience with ritonavir-enhanced HIV therapies and, more recently, COVID-19 therapies demonstrate that boosting doses of ritonavir are well tolerated, with an established safety profile. The mechanisms of PK enhancement by ritonavir result in the potential for drug-drug interactions (DDIs) with several classes of drugs, thus making co-medication management an important consideration with enhanced antiviral therapies. However, rates of DDIs with contraindicated medications are low, suggesting these risks are manageable by infectious disease specialists who have experience with the use of PK enhancers. In this review, we provide an overview of ritonavir's mechanisms of action and describe approaches and resources available to mitigate adverse events and manage concomitant medication in both chronic and short-term settings.

8.
Mol Divers ; 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38517648

RESUMO

Cathepsin B is a cysteine protease lysosomal enzyme involved in several physiological functions. Overexpression of the enzyme enhances its proteolytic activity and causes the breakdown of amyloid precursor protein (APP) into neurotoxic amyloid ß (Aß), a characteristic hallmark of Alzheimer's disease (AD). Therefore, inhibition of the enzyme is a crucial therapeutic aspect for treating the disease. Combined structure and ligand-based drug design strategies were employed in the current study to identify the novel potential cathepsin B inhibitors. Five different pharmacophore models were developed and used for the screening of the ZINC-15 database. The obtained hits were analyzed for the presence of duplicates, interfering PAINS moieties, and structural similarities based on Tanimoto's coefficient. The molecular docking study was performed to screen hits with better target binding affinity. The top seven hits were selected and were further evaluated based on their predicted ADME properties. The resulting best hits, ZINC827855702, ZINC123282431, and ZINC95386847, were finally subjected to molecular dynamics simulation studies to determine the stability of the protein-ligand complex during the run. ZINC123282431 was obtained as the virtual lead compound for cathepsin B inhibition and may be a promising novel anti-Alzheimer agent.

9.
Nat Commun ; 15(1): 2101, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38453892

RESUMO

The architectural design of polycyclic/multisubstituted pentafulvenes has demonstrated great potential for the development of electrochromic materials and biologically active motifs. Unfortunately, the enantioselective construction of such distinctive cores with all carbon quaternary chiral centers has remained untouched to date. Herein, we disclose an enantioselective homologating annulation of cyclopent-4-ene-dione with 3-cyano-4-methylcoumarins through L-tert-leucine derived thiourea catalysis, affording a wide range of enantioenriched polycyclic multisubstituted embedded aminopentafulvenes with excellent stereocontrol (up to 99:1 er) and chemical yields up to 87%. A detailed photophysical and cytotoxicity analysis of racemic and chiral homologated adducts unveils the exceptional behavior of chiral adducts over their racemic analogs, highlighting the importance of stereoselectivity of the developed scaffolds. A cellular uptake experiment in a mammalian fibroblast cell line confirmed the potential of developed polycyclic aminopentafulvene cores as a highly promising labeling dye that can be utilized for bioimaging without any adverse effects.


Assuntos
Tioureia , Estereoisomerismo , Catálise
10.
Chem Commun (Camb) ; 60(18): 2524-2527, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38328816

RESUMO

The efficient cross-dehydrogenative coupling of electronically rich and sterically congested benzofulvene with bi-(hetero)aryl moieties to construct an axially chiral benzofulvene core remains a formidable task. In this study, we describe a highly efficient and practical palladium-catalyzed approach for atroposelective bi-(hetero)aryl benzofulvene synthesis, achieving excellent enantioselectivity with moderate yields. This protocol offers a remarkable opportunity for the direct regio- and enantioselective conversion of C-H bonds of benzofulvene to C-C bonds. Furthermore, the protocol permits the incorporation of benzofulvene with a 4-phenyl coumarin core, enabling access to a novel class of axially chiral coumarins.

11.
3 Biotech ; 14(3): 71, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38362592

RESUMO

In our continuous effort to develop novel antiepileptic drug, a new series of nipecotic acid derivatives having1,3,4-thiadiazole nucleus were designed and synthesized. This study aims to improve the lipophilicity of nipecotic acid by attaching some lipophilic anchors like thiadiazole and substituted aryl acid derivatives. In our previous study, we noticed that the N-substituted oxadiazole derivative of nipecotic acid exhibited significant antiepileptic activity in the rodent model. The synthesized compounds were characterized by FT-IR, 1H-NMR, 13C-NMR, Mass, and elemental analysis. The anticonvulsant activity was evaluated by using the maximal electroshock-induced seizure model in rats (MES) and the subcutaneous pentylenetetrazol (scPTZ) test in mice. None of the compounds were found to be active in the MES model whereas compounds (TN2, TN9, TN12, TN13, and TN15) produced significant protection against the scPTZ-induced seizures model. The compounds showing antiepileptic activity were additionally evaluated for antidepressant activity by using the forced swim test, 5-hydroxytryptophan (5-HTP)-induced head twitch test, and learned helplessness test. All the molecules that showed anticonvulsant activity (TN2, TN9, TN12, TN13, and TN15), also exerted significant antidepressant effects in the animal models. The selected compounds were subjected to different toxicity studies. Compounds were found to have no neurotoxicity in the rota-rod test and devoid of hepatic and renal toxicity in 30 days repeated oral toxicity test. Further, a homology model was developed to perform the in-silico molecular docking and dynamics studies which revealed the similar binding of compound TN9 within the active binding pocket and were found to be the most potent anti-epileptic agent. The market expectation for newly developed antiepileptic thiadiazole-based nipecotic acid derivatives is significant, driven by their potential to offer improved therapeutic outcomes and reduced side effects, addressing a critical need in epilepsy treatment. These innovative compounds hold promise for meeting the demand for more effective and safer antiepileptic medications. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-023-03897-1.

12.
Artigo em Inglês | MEDLINE | ID: mdl-38375842

RESUMO

BACKGROUNDS: Postbiotics produced by gut microbiota have exhibited diverse pharmacological activities. Valeric acid, a postbiotic material produced by gut microbiota and some plant species like valerian, has been explored to have diverse pharmacological activities. METHODS: This narrative review aims to summarise the beneficial role of valeric acid for different health conditions along with its underlying mechanism. In order to get ample scientific evidence, various databases like Science Direct, PubMed, Scopus, Google Scholar and Google were exhaustively explored to collect relevant information. Collected data were arranged and analyzed to reach meaningful a conclusion regarding the bioactivity profiling of valeric acid, its mechanism, and future prospects. RESULTS: Valeric acid belongs to short-chain fatty acids (SCFAs) compounds like acetate, propionate, butyrate, pentanoic (valeric) acid, and hexanoic (caproic) acid. Valeric acid has been identified as one of the potent histone deacetylase (HDAC) inhibitors. In different preclinical in -vitro and in-vivo studies, valeric acid has been found to have anti-cancer, anti-diabetic, antihypertensive, anti-inflammatory, and immunomodulatory activity and affects molecular pathways of different diseases like Alzheimer's, Parkinson's, and epilepsy. CONCLUSION: These findings highlight the role of valeric acid as a potential novel therapeutic agent for endocrine, metabolic and immunity-related health conditions, and it must be tested under clinical conditions to develop as a promising drug.

13.
Biochimie ; 221: 110-124, 2024 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-38311199

RESUMO

l-cysteine, a primary building block of mycothiol, plays an essential role in the defense mechanism of Mycobacterium tuberculosis (Mtb). However, it is unclear how Mtb regulates cysteine biosynthesis as no study has reported the cysteine regulatory complex (CRC) in Mtb. Serine acetyltransferase (SAT) and cysteine synthase (CS) interact to form CRC. Although MtCS has been characterized well, minimal information is available on MtSAT, which synthesizes, O-acetylserine (OAS), the precursor of cysteine. This study fills the gap and provides experimental evidence for the presence of MtCRC and a non-canonical multi-oligomeric MtSAT. We employed multiple analytical methods to characterize the oligomeric and kinetic properties of MtSAT and MtCRC. Results show that MtSAT, lacking >75 N-terminal amino acids exists in three different assembly states; trimer, hexamer, and dodecamer, compared to the single hexameric state of SAT of other bacteria. While hexamers display the highest catalytic turnover, the trimer is the least active. The predominance of trimers at low physiologically relevant concentrations suggests that MtSAT displays the lowest catalytic potential known. Further, the catalytic potential of MtSAT is also significantly reduced in CRC state, in contrast to enhanced activity of SAT in CRC of other organisms. Our study provides insights into multi-oligomeric MtSAT with reduced catalytic potential and demonstrates that both MtSAT and MtCS of Mycobacterium interact to form CRC, although with altered catalytic properties. We discuss our results in light of the altered biochemistry of the last step of canonical sulfate-dependent cysteine biosynthesis of Mycobacterium.

14.
Clin Pharmacokinet ; 63(1): 27-42, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38177893

RESUMO

Nirmatrelvir is a potent and selective inhibitor of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) main protease that is used as an oral antiviral coronavirus disease 2019 (COVID-19) treatment. To sustain unbound systemic trough concentrations above the antiviral in vitro 90% effective concentration value (EC90), nirmatrelvir is coadministered with 100 mg of ritonavir, a pharmacokinetic enhancer. Ritonavir inhibits nirmatrelvir's cytochrome P450 (CYP) 3A4-mediated metabolism which results in renal elimination becoming the primary route of nirmatrelvir elimination when dosed concomitantly. Nirmatrelvir exhibits absorption-limited nonlinear pharmacokinetics. When coadministered with ritonavir in patients with mild-to-moderate COVID-19, nirmatrelvir reaches a maximum concentration of 3.43 µg/mL (11.7× EC90) in approximately 3 h on day 5 of dosing, with a geometric mean day 5 trough concentration of 1.57 µg/mL (5.4× EC90). Drug interactions with nirmatrelvir/ritonavir (PAXLOVIDTM) are primarily attributed to ritonavir-mediated CYP3A4 inhibition, and to a lesser extent CYP2D6 and P-glycoprotein inhibition. Population pharmacokinetics and quantitative systems pharmacology modeling support twice daily dosing of 300 mg/100 mg nirmatrelvir/ritonavir for 5 days, with a reduced 150 mg/100 mg dose for patients with moderate renal impairment. Rapid clinical development of nirmatrelvir/ritonavir in response to the emerging COVID-19 pandemic was enabled by innovations in clinical pharmacology research, including an adaptive phase 1 trial design allowing direct to pivotal phase 3 development, fluorine nuclear magnetic resonance spectroscopy to delineate absorption, distribution, metabolism, and excretion profiles, and innovative applications of model-informed drug development to accelerate development.


Assuntos
COVID-19 , Lactamas , Leucina , Nitrilas , Prolina , Ritonavir , Humanos , Ritonavir/farmacologia , Ritonavir/uso terapêutico , Pandemias , Interações Medicamentosas , Antivirais/farmacologia , Antivirais/uso terapêutico , Combinação de Medicamentos
15.
Bioorg Chem ; 143: 107082, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38199142

RESUMO

The multi-target directed ligand (MTDL) discovery has been gaining immense attention in the development of therapeutics for Alzheimer's disease (AD). The strategy has been evolved as an auspicious approach suitable to combat the heterogeneity and the multifactorial nature of AD. Therefore, multi-targetable chalcone derivatives bearing N-aryl piperazine moiety were designed, synthesized, and evaluated for the treatment of AD. All the synthesized compounds were screened for thein vitro activityagainst acetylcholinesterase (AChE), butylcholinesterase (BuChE), ß-secretase-1 (BACE-1), and inhibition of amyloid ß (Aß) aggregation. Amongst all the tested derivatives, compound 41bearing unsubstituted benzylpiperazine fragment and para-bromo substitution at the chalcone scaffold exhibited balanced inhibitory profile against the selected targets. Compound 41 elicited favourable permeation across the blood-brain barrier in the PAMPA assay. The molecular docking and dynamics simulation studies revealed the binding mode analysis and protein-ligand stability ofthe compound with AChE and BACE-1. Furthermore,itameliorated cognitive dysfunctions and signified memory improvement in thein-vivobehavioural studies (scopolamine-induced amnesia model). Theex vivobiochemical analysis of mice brain homogenates established the reduced AChE and increased ACh levels. The antioxidant activity of compound 41 was accessed with the determination of catalase (CAT) and malondialdehyde (MDA) levels. The findings suggested thatcompound 41, containing a privileged chalcone scaffold, can act as a lead molecule for developing AD therapeutics.


Assuntos
Doença de Alzheimer , Chalcona , Chalconas , Camundongos , Animais , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Chalconas/química , Acetilcolinesterase/metabolismo , Piperazina/farmacologia , Simulação de Acoplamento Molecular , Ligantes , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/química , Piperazinas/farmacologia , Relação Estrutura-Atividade , Desenho de Fármacos
16.
J Clin Pharmacol ; 64(2): 145-154, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37751891

RESUMO

Nirmatrelvir, a novel, potent, orally bioavailable severe acute respiratory syndrome coronavirus 2 main protease inhibitor, coadministered with ritonavir for pharmacokinetic (PK) enhancement is licensed for the treatment of mild to moderate COVID-19 in individuals at increased risk of progression to severe disease. Cytochrome P450 3A4 is the primary metabolic enzyme responsible for nirmatrelvir metabolism; however, when cytochrome P450 3A4 is inhibited by ritonavir, nirmatrelvir is primarily excreted, unchanged, in urine. Because of intended use of nirmatrelvir among individuals with hepatic impairment, this Phase 1 study (NCT05005312) evaluated the effects of hepatic impairment on nirmatrelvir PK parameters to assess the potential need for any dose adjustments in this population. Participants with normal hepatic function or moderate hepatic impairment (n = 8 each) were administered a single 100-mg nirmatrelvir dose, with 100 mg of ritonavir administered 12 hours before, together with, and 12 and 24 hours after nirmatrelvir. Nirmatrelvir median plasma concentrations and systemic exposure measured by area under the plasma concentration-time curve from time zero extrapolated to infinite time and maximum observed plasma concentration values were comparable in both groups. Nirmatrelvir/ritonavir had an acceptable safety profile in both groups, and no clinically significant changes in laboratory measurements, vital signs, or electrocardiogram assessments were observed. Based on these results, no dose adjustment is deemed necessary in patients with moderate hepatic impairment and, by extension, in patients with mild hepatic impairment.


Assuntos
COVID-19 , Hepatopatias , Humanos , Ritonavir , Inibidores de Proteases/uso terapêutico , Tratamento Farmacológico da COVID-19 , Antivirais/farmacocinética , Hepatopatias/metabolismo , Sistema Enzimático do Citocromo P-450
17.
Clin Pharmacol Ther ; 115(1): 42-51, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37597239

RESUMO

Nirmatrelvir is a potent and selective severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) main protease inhibitor. Nirmatrelvir co-packaged with ritonavir (as PAXLOVID) received US Food and Drug Administration (FDA) Emergency Use Authorization (EUA) on December 22, 2021, as an oral treatment for coronavirus disease 2019 (COVID-19) and subsequent new drug application approval on May 25, 2023. Pharmacokinetic (PK) capillary blood sampling at-home using Tasso-M20 micro-volumetric sampling device was implemented in the program, including three phase II/III outpatient and several clinical pharmacology studies supporting the EUA. The at-home sampling complemented venous blood sampling procedures to enrich the PK dataset, to decrease the need for patients' site visit for PK sampling, and to allow different sampling approaches for flexibility and convenience. To demonstrate concordance/equivalence, bridging between venous plasma and Tasso dried blood results was conducted by comparing concentrations and derived PK parameters from both sampling approaches. In addition, a two-compartment population PK model was utilized to bridge the plasma and Tasso data by estimating the PK parameters using blood-to-plasma ratio as a slope parameter. Operational challenges were successfully managed to implement at-home PK sampling in global phase II/III trials. Sample quality was generally very good with less than 3% samples deemed as "not usable" from over 800 samples collected in all the studies. Experience gained from sites and patients will guide future broader implementations.


Assuntos
Lactamas , Ritonavir , Estados Unidos , Humanos , Leucina , Assistência Centrada no Paciente
18.
J Chem Inf Model ; 64(1): 138-149, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-37983534

RESUMO

Osmolytes, small organic compounds, play a key role in modulating the protein stability in aqueous solutions, but the operating mechanism of the osmolyte remains inconclusive. Here, we attempt to clarify the mode of osmolyte action by quantitatively estimating the microheterogeneity of osmolyte-water mixtures with the aid of molecular dynamics simulation, graph theoretical analysis, and spatial distribution measurement in the four osmolyte solutions of trimethylamine-N-oxide (TMAO), tetramethylurea (TMU), dimethyl sulfoxide, and urea. TMAO, acting as a protecting osmolyte, tends to remain isolated with no formation of osmolyte aggregates while preferentially interacting with water, but there is a strong aggregation propensity in the denaturant TMU solution, characterized by favored hydrophobic interactions between TMU molecules. Taken together, the mechanism of osmolyte action on protein stability is proposed as a comprehensive one that encompasses the direct interactions between osmolytes and proteins and indirect interactions through the regulation of water properties in the osmolyte-water mixtures.


Assuntos
Metilaminas , Água , Água/química , Metilaminas/química , Simulação de Dinâmica Molecular , Proteínas , Ureia/química , Soluções
19.
Bioact Mater ; 33: 396-423, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38059120

RESUMO

Glioblastoma (GBM) is an aggressive malignancy of the central nervous system (CNS) that remains incurable despite the multitude of improvements in cancer therapeutics. The conventional chemo and radiotherapy post-surgery have only been able to improve the prognosis slightly; however, the development of resistance and/or tumor recurrence is almost inevitable. There is a pressing need for adjuvant molecular therapies that can successfully and efficiently block tumor progression. During the last few decades, non-coding RNAs (ncRNAs) have emerged as key players in regulating various hallmarks of cancer including that of GBM. The levels of many ncRNAs are dysregulated in cancer, and ectopic modulation of their levels by delivering antagonists or overexpression constructs could serve as an attractive option for cancer therapy. The therapeutic potential of several types of ncRNAs, including miRNAs, lncRNAs, and circRNAs, has been validated in both in vitro and in vivo models of GBM. However, the delivery of these RNA-based therapeutics is highly challenging, especially to the tumors of the brain as the blood-brain barrier (BBB) poses as a major obstacle, among others. Also, since RNA is extremely fragile in nature, careful considerations must be met while designing a delivery agent. In this review we have shed light on how ncRNA therapy can overcome the limitations of its predecessor conventional therapy with an emphasis on smart nanomaterials that can aide in the safe and targeted delivery of nucleic acids to treat GBM. Additionally, critical gaps that currently exist for successful transition from viral to non-viral vector delivery systems have been identified. Finally, we have provided a perspective on the future directions, potential pathways, and target areas for achieving rapid clinical translation of, RNA-based macromolecular therapy to advance the effective treatment of GBM and other related diseases.

20.
J Biomol Struct Dyn ; : 1-17, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38116751

RESUMO

The nucleotide-binding oligomerization domain (NOD)-like receptor (NLR), leucine-rich-repeat (LRR), and pyrin domain containing 3 (NLRP3) is one of the key players in neuroinflammation, which is a major pathological hallmark of Alzheimer's Disease (AD). Activated NLRP3 causes release of pro-inflammatory molecules that aggravate neurodegeneration. Thus, pharmacologically inhibiting the NLRP3 inflammasome has the potential to alleviate the inflammatory injury to the neurons. Coumarin is a multifunctional nucleus with potent anti-inflammatory properties and can be utilized to develop novel drugs for the treatment and management of AD. In the present study, we have explored the NLRP3-inhibitory activities of a library of coumarin derivatives through a computational drug discovery approach. Drug-like, PAINS free, and potentially BBB permeable compounds were screened out and subjected to molecular docking and in silico ADMET studies, resulting in three virtual hits, i.e. MolPort-050-872-358, MolPort-050-884-068, and MolPort-051-135-630. The hits exhibited better NLRP3-binding affinity than MCC950, a selective inhibitor of NLRP3. Further, molecular dynamics (MD) simulations, post-MD simulation analyses, and binding free energy calculations of the hits established their potential as promising virtual leads with a common coumarin scaffold for the inhibition of NLRP3 inflammasome.Communicated by Ramaswamy H. Sarma.

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