Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 92
Filtrar
1.
Chem Asian J ; : e202400557, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38993064

RESUMO

Herein, we have reported a new series of NNS-donor ligands coordinated Ni(II) complexes and utilized them as catalytic activator to synthesize N-alkylated aminesand 1,2-disubstituted benzimidazoles. The separate reaction of  [C9H6N-NH-C(O)-CH2-S-Ar] [Ar = C6H5 (L1); C6H4Cl-4 (L2);C6H4Me-4 (L3) and C6H4-OMe-4 (L4)] with Ni(OAc)2 in methanol at 80°C for 3 hours resulted in octahedral nickel complexes [(L1-H)2Ni] (C1), [(L2-H)2Ni] (C2), [(L3-H)2Ni] (C3), and [(L4-H)2Ni] (C4), respectively. All compounds have been characterized by micro and spectroscopic analysis. The molecular structure of complexes C1-C3 has also been determined by single crystal X-ray diffraction data. The utility of complexes C1-C4 were evaluated for the N-alkylation of aniline with benzyl alcohols, and for 1,2-disubstituted benzimidazoles synthesis. The obtained results indicate that complex C1 showed better catalytic activity in both N-alkylation of amines with benzyl alcohols [catalyst loading: 2.0 mol%; Yield up to 92%], and for 1,2-disubstituted benzimidazoles derivatives [catalyst loading: 2.0 mol%; Yield up to 94%)]. The mechanistic studies suggested that the reaction works through hydrogen borrowing from benzyl alcohol and its subsequent utilization for in situ reduction of imine. The experimentally observed catalytic reactivity patterns of complexes C1-C4 have found in good agreement with the HOMO-LUMO energy gaps obtained by DFT analysis of corresponding complexes.

2.
Int J Biol Macromol ; 274(Pt 2): 133001, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38897497

RESUMO

The issue of environmental contamination, particularly caused by the existence of heavy metal particles, is a major and widely recognized subject that receives substantial global attention. The remediation of Cu(II), Cd(II), Ni(II), and Pb(II) ionic metal particles from synthetic wastewater using chemically treated plant leaves of Ageratum conyzoides (TAC) as a biosorbent was investigated. The biosorption process was implemented utilizing a batch system, wherein several operational parameters were considered, including temperature, pH, agitation time, biosorbent dosage, and initial concentration of the metal ion. Langmuir, Freundlich, Temkin, and D-R isotherm models were used to evaluate equilibrium data. The analyzed parameter exhibits characteristics that were best fitted with the Langmuir isotherm. The observed biosorption capacities (qm) of Cu(II), Pb(II), Ni(II), and Cd(II) ions on the TAC were measured as 51.573, 30.49, 33.53, and 35.91 mg/g, respectively, at a temperature of 22 °C. The affinity sequence of these metal ions follows the order Cu(II) > Pb(II) > Ni(II) > Cd(II). The measured values for the biosorption free energy change (ΔG) of Cu(II), Pb(II), Cd(II), and Ni(II) metal ions ranged from -1.017 to -4.723, -1.368 to -3.612, -2.785 to -5.21, and -1.047 to -5.135 kJ/mol, respectively. The enthalpy (ΔH) for Cu(II), Pb(II), Cd(II), and Ni(II) were determined to be +19.33, +6.82, +14.83, and +38.07 kJ/mol, respectively. Similarly, the corresponding entropy changes (ΔS) for the same series of metal ions were recorded as +0.075, +0.064, +0.063, and +0.135 kJ/mol.K. The pseudo-second-order kinetic models yielded superior outcomes in comparison to the pseudo-first-order kinetic models. The findings of the experiment indicated that the TAC demonstrates favorable efficacy in extracting all four metal ions. Hence, the utilization of biomass derived from Ageratum conyzoides leaves has proven to be a viable and economically feasible approach for biosorption of all four metals.

3.
Chemistry ; : e202401698, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38899378

RESUMO

An air-stable, inexpensive, and isolable cobalt(II) complex (C1) of N-((1-methyl-1H-imidazol-2-yl)methyl)-2-(phenylselanyl)ethan amine (L1) was synthesized and characterized. The complex was used to catalyze a one-pot cascade reaction between 2-(2-aminophenyl)ethanols and benzyl alcohol derivatives. Interestingly, 2-aryl-3-formylindole derivatives were formed instead of N-alkylated or C-3 alkylated indoles. A broad substrate scope can be activated using this protocol with only 5.0 mol% catalyst loading to achieve up to 87% yield of 2-aryl-3-formylindole derivatives. The mechanistic studies suggested that the reaction proceeds through tandem imine formation followed by cyclization.

4.
Cureus ; 16(3): e56412, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38638791

RESUMO

BACKGROUND: Artificial intelligence (AI) based models are explored increasingly in the medical field. The highly contagious pandemic of coronavirus disease 2019 (COVID-19) affected the world and availability of diagnostic tools high resolution computed tomography (HRCT) and/or real-time reverse transcriptase-polymerase chain reaction (RTPCR) was very limited, costly and time consuming. Therefore, the use of AI in COVID-19 for diagnosis using cough sounds can be efficacious and cost effective for screening in clinic or hospital and help in early diagnosis and further management of patients. OBJECTIVES: To develop an accurate and fast voice-processing AI software to determine voice-based signatures in discriminating COVID-19 and non-COVID-19 cough sounds for screening of COVID-19. METHODOLOGY: A prospective study involving 117 patients was performed based on online and/or offline voice data collection of cough sounds of COVID-19 patients in isolation ward of a tertiary care teaching hospital and non-COVID-19 participants using a smart phone. A website-based AI software was developed to identify the cough sounds as COVID-19 or non-COVID-19. The data were divided into three segments including training set, validation set and test set. A pre-processing algorithm was utilized and combined with Short Time Fourier Transform feature representation and Logistic regression model. A precise software was used to identify vocal signatures and K-fold cross validation was carried out. RESULT: A total of 117 audio recordings of cough sounds were collected through the developed website after inclusion-exclusion criteria out of which 52 have been marked belonging to COVID-19 positive, while 65 were marked as COVID-19 negative/unsure /never had COVID-19, which were assumed to be COVID-19 negative based on RT-PCR test results. The mean and standard error values for the accuracies attained at the end of each experiment in training, validation and testing set were found to be 67.34%±0.22, 58.57%±1.11 and 64.60%±1.79 respectively. The weight values were found to be positive which were contributing towards predicting the samples as COVID-19 positive with large spikes around 7.5 kHz, 7.8 kHz, 8.6 kHz and 11 kHz which can be used for classification. CONCLUSION: The proposed AI based approach can be a helpful screening tool for COVID-19 using vocal sounds of cough. It can help the health system by reducing the cost burden and improving overall diagnosis and management of the disease.

5.
Biochim Biophys Acta Mol Cell Res ; 1871(4): 119702, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38408543

RESUMO

Inhibition of Reactive Oxygen Species (ROS) is one of the strategies that Mycobacterium tuberculosis (Mtb) employs as its defence mechanism. In this study, the role of PPE15 (Rv1039c), a late-stage protein, has been investigated in modulating the cellular ROS. We discovered PPE15 to be a secretory protein that downregulates ROS generation in THP1 macrophages. Our in-silico analysis revealed the presence of a eukaryote-like SH3 (SH3e) domain in PPE15. The predicted SH3e-domain of PPE15 was found to interact with cytosolic components of NADPH Oxidase (NOX), p67phox and p47phox through molecular docking. In-vitro experiments using THP1 macrophages showed a diminished NADP/NADPH ratio, indicating reduced NOX activity. We also observed increased levels of p67phox and p47phox in the cytoplasmic fraction of PPE15 treated macrophages as compared to the plasma membrane fraction. To understand the role of the SH3e-domain in ROS modulation, this domain was deleted from the full-length PPE15 (PPE15-/-SH3). We observed an increase in cellular ROS and NADP/NADPH ratio in response to PPE15-/-SH3 protein. The interaction of PPE15-/-SH3 with p67phox or p47phox was also reduced in the cytoplasm, indicating migration of NOX subunits to the plasma membrane. Additionally, M. smegmatis expressing PPE15 was observed to be resistant to oxidative stress with significant intracellular survival in THP1 macrophages as compared to M. smegmatis expressing PPE15-/-SH3. These observations suggest that the SH3e-domain of PPE15 interferes with ROS generation by sequestering NOX components that inhibit NOX assembly at the cell membrane. Therefore, PPE15 acts like a molecular mimic of SH3-domain carrying eukaryotic proteins that can be employed by Mtb at late stages of infection for its survival. These findings give us new insights about the pathogen evading strategy of Mtb which may help in improving the therapeutics for TB treatment.


Assuntos
Mycobacterium tuberculosis , Espécies Reativas de Oxigênio/metabolismo , NADP/metabolismo , Domínios de Homologia de src , Simulação de Acoplamento Molecular , NADPH Oxidases/genética , NADPH Oxidases/metabolismo , Eucariotos
6.
Naunyn Schmiedebergs Arch Pharmacol ; 397(7): 4643-4656, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38349395

RESUMO

Chronic inflammation is defined by an activated microglial state linked to all neurological disorders, including Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis (a motor neuron disease that affects the brain and spinal cord). P2X7 receptors (P2X7R) are ATP-activated ion-gated channels present on microglial surfaces. Prolonged ATP release under pathological settings results in sustained P2X7R activation, which leads to inflammasome development and cytokine release. P2X7R and its enabling roles have recently been linked to neurodegenerative diseases, making it a potential research subject. This research provides an overview of current patents for chemicals, biologics, and medicinal applications. The World Intellectual Property Organization (WIPO), European Patent Office (EPO, Espacenet), and the United States Patent and Trademark Office (USPTO) databases were searched for patents using the keywords "P2X7R and Neuroinflammation." During the study period from 2015 to 2021, 103 patents were examined. The countries that protected these innovations were the United States, PCT (Patent Cooperation Treaty states), Europe, Canada, Australia, and India. Janssen Pharmaceutica NV had the most applications, followed by Acetelion Pharmaceuticals LTD., Renovis Inc., Kelly Michael G, Kincaid Jhon, Merck Patent GMBH, H Lundbeck A/S, and many more. The P2X7R is a possible diagnostic and therapeutic target for cancer, pain disorders, and inflammation. For P2X7 R, several compounds have been discovered and are presently the subject of clinical trial investigations. This study featured patents for P2X7R antagonists, which help treat conditions including neuroinflammation.


Assuntos
Doenças Neuroinflamatórias , Patentes como Assunto , Antagonistas do Receptor Purinérgico P2X , Receptores Purinérgicos P2X7 , Humanos , Receptores Purinérgicos P2X7/metabolismo , Antagonistas do Receptor Purinérgico P2X/uso terapêutico , Antagonistas do Receptor Purinérgico P2X/farmacologia , Animais , Doenças Neuroinflamatórias/tratamento farmacológico
7.
Front Microbiol ; 15: 1302883, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38410395

RESUMO

The prevalence of bacterial persisters is related to their phenotypic diversity and is responsible for the relapse of chronic infections. Tolerance to antibiotic therapy is the hallmark of bacterial persistence. In this study, we have screened a transposon library of Mycobacterium smegmatis mc2155 strain using antibiotic tolerance, survival in mouse macrophages, and biofilm-forming ability of the mutants. Out of 10 thousand clones screened, we selected ten mutants defective in all the three phenotypes. Six mutants showed significantly lower persister abundance under different stress conditions. Insertions in three genes belonging to the pathways of oxidative phosphorylation msmeg_3233 (cydA), biotin metabolism msmeg_3194 (bioB), and oxidative metabolism msmeg_0719, a flavoprotein monooxygenase, significantly reduced the number of live cells, suggesting their role in pathways promoting long-term survival. Another group that displayed a moderate reduction in CFU included a glycosyltransferase, msmeg_0392, a hydrogenase subunit, msmeg_2263 (hybC), and a DNA binding protein, msmeg_2211. The study has revealed potential candidates likely to facilitate the long-term survival of M. smegmatis. The findings offer new targets to develop antibiotics against persisters. Further, investigating the corresponding genes in M. tuberculosis may provide valuable leads in improving the treatment of chronic and persistent tuberculosis infections.

8.
Naunyn Schmiedebergs Arch Pharmacol ; 397(4): 2055-2065, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-37837475

RESUMO

Recent years have witnessed the rise of more recent pandemic outbreaks including COVID-19 and monkeypox. A multinational monkeypox outbreak creates a complex situation that necessitates countermeasures to the existing quo. The first incidence of monkeypox was documented in the 1970s, and further outbreaks led to a public health emergency of international concern. Yet as of right now, neither vaccines nor medicines are certain to treat monkeypox. Even the inability of conducting human clinical trials has prevented thousands of patients from receiving effective disease management. The current state of the disease's understanding, the treatment options available, financial resources, and lastly international policies to control an epidemic state are the major obstacles to controlling epidemics. The current review focuses on the epidemiology of monkeypox, scientific ideas, and available treatments, including potential monkeypox therapeutic methods. As a result, a thorough understanding of monkeypox literature will facilitate in the development of new therapeutic medications for the prevention and treatment of monkeypox.


Assuntos
Citosina/análogos & derivados , Mpox , Organofosfonatos , Humanos , Cidofovir , Benzamidas
9.
Naunyn Schmiedebergs Arch Pharmacol ; 397(1): 41-57, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37566307

RESUMO

Patients with glioblastoma multiforme and anaplastic astrocytoma are treated with temozolomide. Although it has been demonstrated that temozolomide increases GBM patient survival, it has also been connected to negative immune-related adverse effects. Numerous research investigations have shown that flavonoids have strong antioxidant and chemo-preventive effects. Consequently, it might lessen chemotherapeutic medicines' side effects while also increasing therapeutic effectiveness. The need for creating innovative, secure, and efficient drug carriers for cancer therapy has increased over time. Recent research indicates that exosomes have enormous potential to serve as carriers and cutting-edge drug delivery systems to the target cell. In recent years, researchers have been paying considerable attention to exosomes because of their favorable biodistribution, biocompatibility, and low immunogenicity. In the present review, the mechanistic information of the anti-glioblastoma effects of temozolomide and flavonoids coupled with their exosomal delivery to the targeted cell has been discussed. In addition, we discuss the safety aspects of temozolomide and flavonoids against glioma. The in-depth information of temozolomide and flavonoids action via exosomal delivery can unravel novel strategies to target Glioma.


Assuntos
Glioblastoma , Glioma , Humanos , Temozolomida/farmacologia , Temozolomida/uso terapêutico , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Distribuição Tecidual , Glioma/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Antineoplásicos Alquilantes/farmacologia , Antineoplásicos Alquilantes/uso terapêutico
10.
Naunyn Schmiedebergs Arch Pharmacol ; 397(3): 1311-1326, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-37695334

RESUMO

Engineering polymer-based nano-systems have attracted many researchers owing to their unique qualities like shape, size, porosity, mechanical strength, biocompatibility, and biodegradability. Both natural and synthetic polymers can be tuned to get desired surface chemistry and functionalization to improve the efficacy of cancer therapy by promoting targeted delivery to the tumor site. Recent advancements in cancer immunoediting have been able to manage both primary tumor and metastatic lesions via activation of the immune system. The combinations of nano-biotechnology and immunotherapeutic agents have provided positive outcomes by enhancing the host immune response in cancer therapy. The nanoparticles have been functionalized using antibodies, targeted antigens, small molecule ligands, and other novel agents that can interact with biological systems at nanoscale levels. Several polymers, such as polyethylene glycol (PEG), poly(lactic-co-glycolic acid) (PLGA), poly(ε-caprolactone) (PCL), and chitosan, have been approved by the Food and Drug Administration for clinical use in biomedicine. The polymeric nanoformulations such as polymers-antibody/antigen conjugates and polymeric drug conjugates are currently being explored as nanomedicines that can target cancer cells directly or target immune cells to promote anti-cancer immunotherapy. In this review, we focus on scientific developments and advancements on engineered polymeric nano-systems in conjugation with immunotherapeutic agents targeting the tumor microenvironment to improve their efficacy and the safety for better clinical outcomes.


Assuntos
Nanopartículas , Neoplasias , Humanos , Polímeros/química , Polímeros/uso terapêutico , Sistemas de Liberação de Medicamentos , Polietilenoglicóis/química , Neoplasias/tratamento farmacológico , Imunoterapia , Nanopartículas/química , Microambiente Tumoral
11.
Chem Asian J ; 19(4): e202300935, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38116906

RESUMO

Herein, we have reported the synthesis of a macrocyclic organosulfur ligand (L1) having a seventeen-membered macrocyclic ring. Subsequently, the corresponding trans-palladium complex (C1) of bulky macrocyclic organosulfur ligand (L1) was synthesized by reacting it with PdCl2 (CH3 CN)2 salt. The newly synthesized ligand and complex were characterized using various analytical and spectroscopic techniques. The complex showed a square planar geometry with trans orientation of two ligands around the palladium center. The complex possesses intramolecular SCH…Cl interactions of 2.648 Šbetween the macrocyclic ligand and palladium dichloride. The potential energy surface (PES) for the rotational process of C1 suggested a barrier of ~23.81 kcal/mol for chlorine rotation. Furthermore, the bulky macrocyclic organosulfur ligand stabilized palladium complex (C1) was used as a catalyst (2.5 mol %) for α-olefination of nitriles by primary alcohols. The α,ß-unsaturated nitrile compounds were found to be the major product of the reaction (57-78 % yield) with broad substrate scope and large functional group tolerance. Notably, the saturated nitrile product was not observed during the reaction. The mechanistic studies suggested the formation of H2 and H2 O as only by-products of the reaction, thereby making the protocol greener and sustainable.

12.
Exp Cell Res ; 434(2): 113891, 2024 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-38104645

RESUMO

MicroRNAs (miRNAs) have emerged as pivotal regulators of gene expression, playing essential roles in diverse cellular processes, including the development and progression of cancer. Among the numerous proteins influenced by miRNAs, the MARCKS/MARCKSL1 protein, a key regulator of cellular cytoskeletal dynamics and membrane-cytosol communication, has garnered significant attention due to its multifaceted involvement in various cancer-related processes, including cell migration, invasion, metastasis, and drug resistance. Motivated by the encouraging early clinical success of peptides targeting MARCKS in several pathological conditions, this review article delves into the intricate interplay between miRNAs and the MARCKS protein in cancer. Herein, we have highlighted the latest findings on specific miRNAs that modulate MARCKS/MARCKSL1 expression, providing a comprehensive overview of their roles in different cancer types. We have underscored the need for in-depth investigations into the therapeutic feasibility of targeting the miRNA-MARCKS axis in cancer, taking cues from the successes witnessed in related fields. Unlocking the full potential of miRNA-mediated MARCKS regulation could pave the way for innovative and effective therapeutic interventions against various cancer types.


Assuntos
MicroRNAs , Neoplasias , Humanos , Substrato Quinase C Rico em Alanina Miristoilada/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Proteína Quinase C/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/metabolismo , Neoplasias/genética , Fosforilação , Proteínas de Ligação a Calmodulina/metabolismo , Proteínas dos Microfilamentos/metabolismo
13.
J Cancer Res Clin Oncol ; 149(19): 17709-17726, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37919474

RESUMO

BACKGROUND: Melittin is a water-soluble cationic peptide derived from bee venom that has been thoroughly studied for the cure of different cancers. However, the unwanted interactions of melittin produce hemolytic and cytotoxic effects that hinder their therapeutic applications. To overcome the shortcomings, numerous research groups have adopted different approaches, including conjugation with tumor-targeting proteins, gene therapy, and encapsulation in nanoparticles, to reduce the non-specific cytotoxic effects and potentiate their anti-cancerous activity. PURPOSE: This article aims to provide mechanistic insights into the chemopreventive activity of melittin and its nanoversion in combination with standard anti-cancer drugs for the treatment of cancer. METHODS: We looked over the pertinent research on melittin's chemopreventive properties in online databases such as PubMed and Scopus. CONCLUSION: In the present article, the anti-cancerous effects of melittin on different cancers have been discussed very nicely, as have their possible mechanisms of action to act against different tumors. Besides, it interacts with different signal molecules that regulate the diverse pathways of cancerous cells, such as cell cycle arrest, apoptosis, metastasis, angiogenesis, and inflammation. We also discussed the recent progress in the synergistic combination of melittin with standard anti-cancer drugs and a nano-formulated version of melittin for targeted delivery to improve its anticancer potential.


Assuntos
Antineoplásicos , Neoplasias , Animais , Meliteno/farmacologia , Meliteno/química , Meliteno/genética , Neoplasias/patologia , Antineoplásicos/uso terapêutico , Técnicas de Cultura de Células , Modelos Animais , Proliferação de Células
14.
Molecules ; 28(22)2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-38005250

RESUMO

Flavopiridol is a flavone synthesized from the natural product rohitukine, which is derived from an Indian medicinal plant, namely Dysoxylum binectariferum Hiern. A deeper understanding of the biological mechanisms by which such molecules act may allow scientists to develop effective therapeutic strategies against a variety of life-threatening diseases, such as cancer, viruses, fungal infections, parasites, and neurodegenerative diseases. Mechanistic insight of flavopiridol reveals its potential for kinase inhibitory activity of CDKs (cyclin-dependent kinases) and other kinases, leading to the inhibition of various processes, including cell cycle progression, apoptosis, tumor proliferation, angiogenesis, tumor metastasis, and the inflammation process. The synthetic derivatives of flavopiridol have overcome a few demerits of its parent compound. Moreover, these derivatives have much improved CDK-inhibitory activity and therapeutic abilities for treating severe human diseases. It appears that flavopiridol has potential as a candidate for the formulation of an integrated strategy to combat and alleviate human diseases. This review article aims to unravel the potential therapeutic effectiveness of flavopiridol and its possible mechanism of action.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Quinases Ciclina-Dependentes , Fosforilação , Neoplasias/tratamento farmacológico , Antineoplásicos/farmacologia , Apoptose
15.
bioRxiv ; 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37693425

RESUMO

Current influenza vaccine strategies have yet to overcome significant obstacles, including rapid antigenic drift of seasonal influenza viruses, in generating efficacious long-term humoral immunity. Due to the necessity of germinal center formation in generating long-lived high affinity antibodies, the germinal center has increasingly become a target for the development of novel or improvement of less-efficacious vaccines. However, there remains a major gap in current influenza research to effectively target T follicular helper cells during vaccination to alter the germinal center reaction. In this study, we used a heterologous infection or immunization priming strategy to seed an antigen-specific memory CD4+ T cell pool prior to influenza infection in mice to evaluate the effect of recalled memory T follicular helper cells in increased help to influenza-specific primary B cells and enhanced generation of neutralizing antibodies. We found that heterologous priming with intranasal infection with acute lymphocytic choriomeningitis virus (LCMV) or intramuscular immunization with adjuvanted recombinant LCMV glycoprotein induced increased antigen-specific effector CD4+ T and B cellular responses following infection with a recombinant influenza strain that expresses LCMV glycoprotein. Heterologously primed mice had increased expansion of secondary Th1 and Tfh cell subsets, including increased CD4+ TRM cells in the lung. However, the early enhancement of the germinal center cellular response following influenza infection did not impact influenza-specific antibody generation or B cell repertoires compared to primary influenza infection. Overall, our study suggests that while heterologous infection/immunization priming of CD4+ T cells is able to enhance the early germinal center reaction, further studies to understand how to target the germinal center and CD4+ T cells specifically to increase long-lived antiviral humoral immunity are needed.

16.
Chem Asian J ; 18(19): e202300628, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37602812

RESUMO

This report describes the synthesis of a new NNSe pincer ligand and its mono- and dinuclear palladium(II) pincer complexes. In the absence of a base, a dinuclear palladium pincer complex (C1) was isolated, while in the presence of Et3 N base a mononuclear palladium pincer complex (C2) was obtained. The new ligand and complexes were characterized using techniques like 1 H, 13 C{1 H} nuclear magnetic resonance (NMR), fourier transform infrared (FTIR), high-resolution mass spectrometry (HRMS), ultraviolet-visible (UV-Visible), and cyclic voltammetry. Both the complexes showed pincer coordination mode with a distorted square planar geometry. The complex C1 has two pincer ligands attached through a Pd-Pd bond in a dinuclear pincer fashion. The air and moisture-insensitive, thermally robust palladium pincer complexes were used as the catalyst for decarboxylative direct C-H heteroarylation of (hetero)arenes. Among the complexes, dinuclear pincer complex C1 showed better catalytic activity. A variety of (hetero)arenes were successfully activated (43-87 % yield) using only 2.5 mol % of catalyst loading under mild reaction conditions. The PPh3 and Hg poisoning experiments suggested a homogeneous nature of catalysis. A plausible reaction pathway was proposed for the dinuclear palladium pincer complex catalyzed decarboxylative C-H bond activation reaction of (hetero)arenes.

17.
Nat Commun ; 14(1): 4253, 2023 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-37474523

RESUMO

Immune checkpoint blockade therapy is beneficial and even curative for some cancer patients. However, the majority don't respond to immune therapy. Across different tumor types, pre-existing T cell infiltrates predict response to checkpoint-based immunotherapy. Based on in vitro pharmacological studies, mouse models and analyses of human melanoma patients, we show that the cytokine GDF-15 impairs LFA-1/ß2-integrin-mediated adhesion of T cells to activated endothelial cells, which is a pre-requisite of T cell extravasation. In melanoma patients, GDF-15 serum levels strongly correlate with failure of PD-1-based immune checkpoint blockade therapy. Neutralization of GDF-15 improves both T cell trafficking and therapy efficiency in murine tumor models. Thus GDF-15, beside its known role in cancer-related anorexia and cachexia, emerges as a regulator of T cell extravasation into the tumor microenvironment, which provides an even stronger rationale for therapeutic anti-GDF-15 antibody development.


Assuntos
Melanoma , Linfócitos T , Humanos , Camundongos , Animais , Linfócitos T/patologia , Antígeno-1 Associado à Função Linfocitária , Células Endoteliais/patologia , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Melanoma/patologia , Imunoterapia , Microambiente Tumoral
18.
Retina ; 43(11): 1922-1927, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37490757

RESUMO

PURPOSE: To assess the characteristics of completed panretinal photocoagulation (PRP), using ultra-widefield imaging in proliferative diabetic retinopathy. METHODS: Quantitative assessment of ultra-widefield imaging images of 133 patients with proliferative diabetic retinopathy with completed PRP was made using ImageJ software. The parameters assessed included distance of laser spots from the optic disk, foveal center, superior and inferior arcades, and extent of the maximum width of laser. Areas assessed were total area of the image, area of the inner limit within which laser spots are restricted, minimum areas of unlasered patches, total area lasered, and ideal area to be covered by PRP. RESULTS: Two hundred one images were assessed for the final analysis. The mean distance of laser spots was 4.2 ± 2.4 mm from the optic disk (nasal) and 6.6 ± 2.5 mm from the foveal center (temporal). The mean distance of laser spots from the superior arcade vessel was 3.2 ± 1.9 mm and 6.2 ± 4.4 mm from the inferior arcade. The mean area of the retina that should have been ideally lasered was found to be 900 ± 267 mm 2 , and the actual area lasered was found to be 681 ± 254.4 mm 2 . CONCLUSION: Approximately one-quarter area of the retina continues to remain ischemic because of the lack of inadequate coverage of PRP. Further longitudinal studies are recommended, using ultra-widefield imaging to objectively assess the adequacy of PRP and its role in modulating the course of progression of the retinopathy.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Disco Óptico , Humanos , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/cirurgia , Retina/diagnóstico por imagem , Retina/cirurgia , Fotocoagulação a Laser/métodos , Tomografia de Coerência Óptica/métodos
19.
Naunyn Schmiedebergs Arch Pharmacol ; 396(12): 3443-3458, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37490121

RESUMO

One of the well-studied older molecules, quercetin, is found in large quantities in many fruits and vegetables. Natural anti-oxidant quercetin has demonstrated numerous pharmacological properties in preclinical and clinical research, including anti-inflammatory and anti-cancer effects. Due to its ability to control cell signaling pathways, including NF-κB, p53, activated protein-1 (AP-1), STAT3, and epidermal growth response-1 (Egr-1), which is essential in the initiation and proliferation of cancer, it has gained a lot of fame as an anticancer molecule. Recent research suggests that using nanoformulations can help quercetin to overcome its hydrophobicity while also enhancing its stability and cellular bioavailability both in vitro and in vivo. The main aim of this review is to focus on the comprehensive insights of several nanoformulations, including liposomes, nano gels, micelles, solid lipid nanoparticles (SLN), polymer nanoparticles, gold nanoparticles, and cyclodextrin complexes, to transport quercetin for application in cancer.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Neoplasias , Humanos , Quercetina/farmacologia , Ouro , Antioxidantes/farmacologia , Neoplasias/tratamento farmacológico
20.
Exp Biol Med (Maywood) ; 248(9): 820-828, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37387217

RESUMO

Chinese native medicine Scutellaria baicalensis Georgi, also referred to as Chinese skullcap or Huang-Qin, is frequently used to treat cancer, viral infections, and seizures. This plant's abundance of flavones (wogonoside) and their related aglycones (wogonin) is responsible for many of its pharmacologic effects. A significant ingredient in S. baicalensis that has been the subject of the most research is wogonin. Numerous preclinical investigations revealed that wogonin suppresses tumor growth by cell cycle arrest, stimulating cell death and preventing metastasis. This review focuses on a complete overview of published reports that suggest chemopreventive action of wogonin and the mechanistic insights behind these neoplastic activities. It also emphasizes the synergistic improvements made by wogonin in chemoprevention. The factual data in this mini-review stimulate additional research on chemistry and toxicological profile of wogonin to confirm its safety issues. This review will encourage researchers to generalize the merits of wogonin to be used as potential compound for cancer treatment.


Assuntos
Antineoplásicos Fitogênicos , Medicamentos de Ervas Chinesas , Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Antineoplásicos Fitogênicos/farmacologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...