Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 27.538
Filtrar
1.
Int J Mol Sci ; 25(7)2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38612735

RESUMO

The antitumor activity of different ent-kaurane diterpenes has been extensively studied. Several investigations have demonstrated the excellent antitumor activity of synthetic derivatives of the diterpene atractyligenin. In this research, a series of new synthetic amides and their 15,19-di-oxo analogues obtained from atractyligenin by modifying the C-2, C-15, and C-19 positions were designed in order to dispose of a set of derivatives with different substitutions at the amidic nitrogen. Using different concentrations of the obtained compounds (10-300 µM) a reduction in cell viability of HCT116 colon cancer cells was observed at 48 h of treatment. All the di-oxidized compounds were more effective than their alcoholic precursors. The di-oxidized compounds had already reduced the viability of two colon cancer cells (HCT116 and Caco-2) at 24 h when used at low doses (2.5-15 µM), while they turned out to be poorly effective in differentiated Caco-2 cells, a model of polarized enterocytes. The data reported here provide evidence that di-oxidized compounds induced apoptotic cell death, as demonstrated by the appearance of condensed and fragmented DNA in treated cells, as well as the activation of caspase-3 and fragmentation of its target PARP-1.


Assuntos
Atractilosídeo/análogos & derivados , Neoplasias do Colo , Diterpenos do Tipo Caurano , Humanos , Diterpenos do Tipo Caurano/farmacologia , Células CACO-2 , Neoplasias do Colo/tratamento farmacológico , Amidas , Apoptose
2.
J Pineal Res ; 76(2): e12941, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38606814

RESUMO

The labeled ligand commonly employed in competition binding studies for melatonin receptor ligands, 2-[125I]iodomelatonin, showed slow dissociation with different half-lives at the two receptor subtypes. This may affect the operational measures of affinity constants, which at short incubation times could not be obtained in equilibrium conditions, and structure-activity relationships, as the Ki values of tested ligands could depend on either interaction at the binding site or the dissociation path. To address these issues, the kinetic and saturation binding parameters of 2-[125I]iodomelatonin as well as the competition constants for a series of representative ligands were measured at a short (2 h) and a long (20 h) incubation time. Concurrently, we simulated by molecular modeling the dissociation path of 2-iodomelatonin from MT1 and MT2 receptors and investigated the role of interactions at the binding site on the stereoselectivity observed for the enantiomers of the subtype-selective ligand UCM1014. We found that equilibrium conditions for 2-[125I]iodomelatonin binding can be reached only with long incubation times, particularly for the MT2 receptor subtype, for which a time of 20 h approximates this condition. On the other hand, measured Ki values for a set of ligands including agonists, antagonists, nonselective, and subtype-selective compounds were not significantly affected by the length of incubation, suggesting that structure-activity relationships based on data collected at shorter time reflect different interactions at the binding site. Molecular modeling simulations evidenced that the slower dissociation of 2-iodomelatonin from the MT2 receptor can be related to the restricted mobility of a gatekeeper tyrosine along a lipophilic path from the binding site to the membrane bilayer. The enantiomers of the potent, MT2-selective agonist UCM1014 were separately synthesized and tested. Molecular dynamics simulations of the receptor-ligand complexes provided an explanation for their stereoselectivity as due to the preference shown by the eutomer at the binding site for the most abundant axial conformation adopted by the ligand in solution. These results suggest that, despite the slow-binding kinetics occurring for the labeled ligand, affinity measures at shorter incubation times give robust results consistent with known structure-activity relationships and with interactions taken at the receptor binding site.


Assuntos
Melatonina , Quinolinas , Ligantes , Receptores de Melatonina , Melatonina/metabolismo , Amidas , Receptor MT2 de Melatonina/metabolismo , Receptor MT1 de Melatonina/metabolismo
3.
Cells ; 13(7)2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38607071

RESUMO

Adjuvant treatment for Glioblastoma Grade 4 with Temozolomide (TMZ) inevitably fails due to therapeutic resistance, necessitating new approaches. Apoptosis induction in GB cells is inefficient, due to an excess of anti-apoptotic XPO1/Bcl-2-family proteins. We assessed TMZ, Methotrexate (MTX), and Cytarabine (Ara-C) (apoptosis inducers) combined with XPO1/Bcl-2/Mcl-1-inhibitors (apoptosis rescue) in GB cell lines and primary GB stem-like cells (GSCs). Using CellTiter-Glo® and Caspase-3 activity assays, we generated dose-response curves and analyzed the gene and protein regulation of anti-apoptotic proteins via PCR and Western blots. Optimal drug combinations were examined for their impact on the cell cycle and apoptosis induction via FACS analysis, paralleled by the assessment of potential toxicity in healthy mouse brain slices. Ara-C and MTX proved to be 150- to 10,000-fold more potent in inducing apoptosis than TMZ. In response to inhibitors Eltanexor (XPO1; E), Venetoclax (Bcl-2; V), and A1210477 (Mcl-1; A), genes encoding for the corresponding proteins were upregulated in a compensatory manner. TMZ, MTX, and Ara-C combined with E, V, and A evidenced highly lethal effects when combined. As no significant cell death induction in mouse brain slices was observed, we conclude that this drug combination is effective in vitro and expected to have low side effects in vivo.


Assuntos
Amidas , Antineoplásicos , Compostos Bicíclicos Heterocíclicos com Pontes , Glioblastoma , Pirimidinas , Sulfonamidas , Animais , Camundongos , Temozolomida/farmacologia , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Metotrexato/farmacologia , Metotrexato/uso terapêutico , Citarabina/farmacologia , Citarabina/uso terapêutico , Antineoplásicos Alquilantes/farmacologia , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Apoptose
4.
Eur Radiol Exp ; 8(1): 41, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38584248

RESUMO

BACKGROUND: We investigated the value of three-dimensional amide proton transfer-weighted imaging (3D-APTWI) in the diagnosis of early-stage breast cancer (BC) and its correlation with the immunohistochemical characteristics of malignant lesions. METHODS: Seventy-eight women underwent APTWI and dynamic contrast-enhanced (DCE)-MRI. Pathological results were categorized as either benign (n = 43) or malignant (n = 37) lesions. The parameters of APTWI and DCE-MRI were compared between the benign and malignant groups. The diagnostic value of 3D-APTWI was evaluated using the area under the receiver operating characteristic curve (ROC-AUC) to establish a diagnostic threshold. Pearson's correlation was used to analyze the correlation between the magnetization transfer asymmetry (MTRasym) and immunohistochemical characteristics. RESULTS: The MTRasym and time-to-peak of malignancies were significantly lower than those of benign lesions (all p < 0.010). The volume transfer constant, rate constant, and wash-in and wash-out rates of malignancies were all significantly greater than those of benign lesions (all p < 0.010). ROC-AUCs of 3D-APTWI, DCE-MRI, and 3D-APTWI+DCE to differential diagnosis between early-stage BC and benign lesions were 0.816, 0.745, and 0.858, respectively. Only the difference between AUCAPT+DCE and AUCDCE was significant (p < 0.010). When a threshold of MTRasym for malignancy for 2.42%, the sensitivity and specificity of 3D-APTWI for BC diagnosis were 86.5% and 67.6%, respectively; MTRasym was modestly positively correlated with pathological grade (r = 0.476, p = 0.003) and Ki-67 (r = 0.419, p = 0.020). CONCLUSIONS: 3D-APTWI may be used as a supplementary method for patients with contraindications of DCE-MRI. MTRasym can imply the proliferation activities of early-stage BC. RELEVANCE STATEMENT: 3D-APTWI can be an alternative diagnostic method for patients with early-stage BC who are not suitable for contrast injection. KEY POINTS: • 3D-APTWI reflects the changes in the microenvironment of early-stage breast cancer. • Combined 3D-APTWI is superior to DCE-MRI alone for early-stage breast cancer diagnosis. • 3D-APTWI improves the diagnostic accuracy of early-stage breast cancer.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Prótons , Amidas , Estudos Prospectivos , Imageamento por Ressonância Magnética/métodos , Microambiente Tumoral
5.
BMC Pregnancy Childbirth ; 24(1): 254, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589777

RESUMO

BACKGROUND: Epidural test dose for labor analgesia is controversial and varies widely in clinical practice. It is currently unclear whether using a portion of the initial dose for analgesia as the test dose delays the onset time of analgesia, compared to the traditional test dose. METHODS: One hundred and twenty-six parturients who chose epidural analgesia during labor were randomly assigned to two groups. The first dose in group L was 3 ml 1.5% lidocaine, and in the RF group was 10 ml 0.1% ropivacaine combined with 2 µg/ml fentanyl. After 3 min of observation, both groups received 8 ml 0.1% ropivacaine combined with 2 µg/ml fentanyl. The onset time of analgesia, motor and sensory blockade level, numerical pain rating scale, patient satisfaction score, and side effects were recorded. RESULTS: The onset time of analgesia in group RF was similar to that in group L (group RF vs group L, 7.0 [5.0-9.0] minutes vs 8.0 [5.0-11.0] minutes, p = 0.197). The incidence of foot numbness (group RF vs group L, 34.9% vs 57.1%, p = 0.020) and foot warming (group RF vs group L, 15.9% vs 47.6%, p < 0.001) in group RF was significantly lower than that in group L. There was no difference between the two groups on other outcomes. CONCLUSIONS: Compared with 1.5% lidocaine 3 ml, 0.1% ropivacaine 10 ml combined with 2 µg/ml fentanyl as an epidural test dose did not delay the onset of labor analgesia, and the side effects were slightly reduced. CLINICAL TRIAL REGISTRATION: http://www.chictr.org.cn (ChiCTR2100043071).


Assuntos
Analgesia Epidural , Analgesia Obstétrica , Feminino , Humanos , Ropivacaina , Anestésicos Locais/efeitos adversos , Amidas/efeitos adversos , Analgesia Obstétrica/efeitos adversos , Analgésicos , Fentanila/efeitos adversos , Lidocaína , Analgesia Epidural/efeitos adversos , Método Duplo-Cego
6.
J Phys Chem B ; 128(14): 3350-3359, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38564809

RESUMO

Secondary coordination sphere (SCS) interactions have been shown to play important roles in tuning reduction potentials and electron transfer (ET) properties of the Type 1 copper proteins, but the precise roles of these interactions are not fully understood. In this work, we examined the influence of F114P, F114N, and N47S mutations in the SCS on the electronic structure of the T1 copper center in azurin (Az) by studying the hyperfine couplings of (i) histidine remote Nε nitrogens and (ii) the amide Np using the two-dimensional (2D) pulsed electron paramagnetic resonance (EPR) technique HYSCORE (hyperfine sublevel correlation) combined with quantum mechanics/molecular mechanics (QM/MM) and DLPNO-CCSD calculations. Our data show that some components of hyperfine tensor and isotropic coupling in N47SAz and F114PAz (but not F114NAz) deviate by up to ∼±20% from WTAz, indicating that these mutations significantly influence the spin density distribution between the CuII site and coordinating ligands. Furthermore, our calculations support the assignment of Np to the backbone amide of residue 47 (both in Asn and Ser variants). Since the spin density distributions play an important role in tuning the covalency of the Cu-Scys bond of Type 1 copper center that has been shown to be crucial in controlling the reduction potentials, this study provides additional insights into the electron spin factor in tuning the reduction potentials and ET properties.


Assuntos
Nativos do Alasca , Azurina , Azurina/genética , Azurina/química , Cobre/química , Nitrogênio/química , Mutação , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Amidas
7.
Sci Rep ; 14(1): 8291, 2024 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594566

RESUMO

Neonicotinoids (NEOs) have been designed to act selectively on insect nicotinic acetylcholine receptors (nAChRs). However, nAChRs are also expressed in vertebrate immune cells, so NEOs may interfere with the immune system in exposed non-target animals. The present study shows that NEOs: imidacloprid and thiacloprid, and their main metabolites: desnitro-imidacloprid and thiacloprid amide, at sub-micromolar concentrations ranging from 2.25 to 20 µM, affect the immune cells of fish. This was found both in primary cultures of leukocytes isolated from the carp head kidney and in the continuous adherent carp monocyte/macrophage cell line. Moreover, the results revealed that the studied pesticides and metabolites generate oxidative stress in carp immune cells and that this is one of the most important mechanisms of neonicotinoid immunotoxicity. Significant increases were observed in the formation of ROS and malondialdehyde (MDA). The antioxidant status alteration was linked with decrease in antioxidant enzyme activity: superoxide dismutase (SOD), catalase (CAT), and non-enzymatic antioxidant glutathione (GSH). Importantly, the metabolites: desnitro-imidacloprid and thiacloprid amide showed significantly higher cytotoxicity towards fish leukocytes than their parent compounds, imidacloprid and thiacloprid, which emphasizes the importance of including intermediate metabolites in toxicology studies.


Assuntos
Carpas , Inseticidas , Receptores Nicotínicos , Tiazinas , Animais , Inseticidas/toxicidade , Carpas/metabolismo , Antioxidantes/metabolismo , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Estresse Oxidativo , Receptores Nicotínicos/metabolismo , Leucócitos/metabolismo , Amidas
8.
J Infect Public Health ; 17(5): 897-905, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38569269

RESUMO

BACKGROUND: The efficacy of the viral clearance and clinical outcomes of favipiravir (FPV) in outpatients being treated for coronavirus disease 2019 (COVID-19) is unclear. Ivermectin (IVM), niclosamide (NCL), and FPV demonstrated synergistic effects in vitro for exceed 78% inhibiting severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) replication. METHODS: A phase 2, open-label, 1:1, randomized, controlled trial was conducted on Thai patients with mild-to-moderate COVID-19 who received either combination FPV/IVM/NCL therapy or FPV alone to assess the rate of viral clearance among individuals with mild-to-moderate COVID-19. RESULTS: Sixty non-high-risk comorbid patients with mild-to-moderate COVID-19 were randomized; 30 received FPV/IVM/NCL, and 30 received FPV alone. Mixed-effects multiple linear regression analysis of the cycle threshold value from SARS-CoV-2 PCR demonstrated no statistically significant differences in viral clearance rates between the combined FPV/IVM/NCL therapy group and the FPV-alone group. World Health Organization Clinical Progression scores and symptomatic improvement did not differ between arms on days 3, 6, and 10, and no adverse events were reported. No patients required hospitalization, intensive care unit admission, or supplemental oxygen or died within 28 days. C-reactive protein on day 3 was lower in the FPV/IVM/NCL group. CONCLUSION: Viral clearance rates did not differ significantly between the FPV/IVM/NCL combination therapy and FPV-alone groups of individuals with mild-to-moderate COVID-19, although the combined regimen demonstrated a synergistic effect in vitro. No discernible clinical benefit was observed. Further research is required to explore the potential benefits of FVP beyond its antiviral effects. TRIAL REGISTRATION: TCTR20230403007, Registered 3 April 2023 - Retrospectively registered,https://trialsearch.who.int/Trial2.aspx?TrialID=TCTR20230403007.


Assuntos
Amidas , COVID-19 , Pirazinas , Adulto , Humanos , SARS-CoV-2 , Ivermectina/uso terapêutico , Niclosamida , Aceleração , Resultado do Tratamento , Antivirais/efeitos adversos
9.
Pol Merkur Lekarski ; 52(2): 178-188, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38642353

RESUMO

OBJECTIVE: Aim: To evaluate the cytotoxic activity of newly synthesized a series of novel HDAC inhibitors comprising sulfonamide as zinc binding group and Isatin derivatives as cap group joined by mono amide linker as required to act as HDAC inhibitors. PATIENTS AND METHODS: Materials and Methods: The utilization of sulfonamide as zinc binding group joined by N-alkylation reaction with ethyl-bromo hexanoate as linker group that joined by amide reaction with Isatin derivatives as cap groups which known to possess antitumor activity in the designed of new histone deacetylase inhibitors and using the docking and MTT assay to evaluate the compounds. RESULTS: Results: Four compounds have been synthesized and characterized successfully by ART-FTIR, NMR and ESI-Ms. the compounds were synthesized and characterized by successfully by ART-FTIR, NMR and ESI- Ms. Assessed for their cytotoxic activity against human colon adenocarcinoma MCF-7 (IC50, I=105.15, II=60.00, III=54.11, IV=56.57, vorinostat=28.41) and hepatoblastoma HepG2 (IC50, I=63.91, II=135.18, III=118.85, IV=51.46, vorinostat=37.50). Most of them exhibited potent HDAC inhibitory activity and significant cytotoxicity. CONCLUSION: Conclusions: The synthesized compounds (I, II, III and IV) showed cytotoxicity toward MCF-7 and HepG2 cancer cell lines and their docking analysis provided a preliminary indication that they are viable [HDAC6] candidates.


Assuntos
Adenocarcinoma , Antineoplásicos , Neoplasias do Colo , Isatina , Humanos , Inibidores de Histona Desacetilases/farmacologia , Inibidores de Histona Desacetilases/química , Vorinostat/farmacologia , Isatina/farmacologia , Linhagem Celular Tumoral , Amidas/farmacologia , Desenho de Fármacos , Antineoplásicos/farmacologia , Sulfonamidas/farmacologia , Zinco/metabolismo , Zinco/farmacologia , Proliferação de Células , Estrutura Molecular
10.
Medicine (Baltimore) ; 103(16): e37785, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38640301

RESUMO

The BICSTaR (BICtegravir Single Tablet Regimen) study is investigating the effectiveness and safety of bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) in people with human immunodeficiency virus (HIV) treated in routine clinical practice. BICSTaR is an ongoing, prospective, observational cohort study across 14 countries. Treatment-naïve (TN) and treatment-experienced (TE) people with HIV (≥18 years of age) are being followed for 24 months. We present an analysis of the primary endpoint (HIV-1 RNA < 50 copies/mL; missing-equals-excluded [M = E]) at month 12 in the BICSTaR Canada cohort, including secondary (CD4 count, CD4/CD8 ratio, safety/tolerability) and exploratory (persistence, treatment satisfaction) endpoints. In total, 201 participants were enrolled in the BICSTaR Canada cohort. The analysis population included 170 participants (TN, n = 10; TE, n = 160), with data collected between November 2018 and September 2020. Of the participants, 88% were male, 72% were White, and 90% had ≥ 1 comorbid condition(s). Median (quartile [Q]1-Q3) age was 50 (39-58) years and baseline CD4 count was 391.5 (109.0-581.0) cells/µL in TN participants and 586.0 (400.0-747.0) cells/µL in TE participants. After 12 months of B/F/TAF treatment, HIV-1 RNA was < 50 copies/mL in 100% (9/9) of TN-active participants and 97% (140/145) of TE-active participants (M = E analysis). Median (Q1-Q3) CD4 cell count increased by +195 (125-307) cells/µL in TN participants and by + 30 (-50 to 123) cells/µL in TE participants. Persistence on B/F/TAF was high through month 12 with 10% (1/10) of TN and 7 % (11/160) of TE participants discontinuing B/F/TAF within 12 months of initiation of treatment. No resistance to B/F/TAF emerged. Study drug-related adverse events occurred in 7% (12/169) of participants, leading to B/F/TAF discontinuation in 4 of 169 participants. Improvements in treatment satisfaction were observed in TE participants. B/F/TAF demonstrated high levels of effectiveness, persistence, and treatment satisfaction, and was well tolerated through month 12 in people with HIV treated in routine clinical practice in Canada.


Assuntos
Alanina , Amidas , Fármacos Anti-HIV , Infecções por HIV , HIV-1 , Piperazinas , Piridonas , Tenofovir/análogos & derivados , Masculino , Humanos , Pré-Escolar , Pessoa de Meia-Idade , Feminino , Infecções por HIV/tratamento farmacológico , Emtricitabina/efeitos adversos , Estudos Prospectivos , Adenina/uso terapêutico , Resultado do Tratamento , Canadá , Compostos Heterocíclicos com 3 Anéis/uso terapêutico , Fármacos Anti-HIV/efeitos adversos , Combinação de Medicamentos , RNA
11.
J Phys Chem B ; 128(15): 3605-3613, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38592238

RESUMO

Since Hofmeister's seminal studies in the late 19th century, it has been known that salts and buffers can drastically affect the properties of peptides and proteins. These Hofmeister effects can be conceived of in terms of three distinct phenomena/mechanisms: water-salt interactions that indirectly induce the salting-out of a protein by water sequestration by the salt, and direct salt-protein interactions that can either salt-in or salt-out the protein. Unfortunately, direct salt-protein interactions responsible for Hofmeister effects are weak and difficult to quantify. As such, they are frequently construed of as being nonspecific. Nevertheless, there has been considerable effort to better specify these interactions. Here, we use pentapeptides to demonstrate the utility of the H-dimension of nuclear magnetic resonance (NMR) spectroscopy to assess anion binding using N-H signal shifts. We qualify binding using these, demonstrating the upfield shifts induced by anion association and revealing how they are much larger than the corresponding downfield shifts induced by magnetic susceptibility and other ionic strength change effects. We also qualify binding in terms of how the pattern of signal shifts changes with point mutations. In general, we find that the observed upfield shifts are small compared with those induced by anion binding to amide-based hosts, and MD simulations suggest that this is so. Thus, charge-diffuse anions associate mostly with the nonpolar regions of the peptide rather than directly interacting with the amide N-H groups. These findings reveal the utility of 1H NMR spectroscopy for qualifying affinity to peptides─even when affinity constants are very low─and serve as a benchmark for using NMR spectroscopy to study anion binding to more complex systems.


Assuntos
Peptídeos , Proteínas , Peptídeos/química , Ânions/química , Proteínas/química , Amidas/química , Cloreto de Sódio , Água
12.
Public Health ; 230: 198-206, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38574425

RESUMO

OBJECTIVES: Long COVID is characterized by persistent symptoms lasting for 4 weeks or more following the acute infection with SARS-CoV-2. Risk factors for long COVID and the impact of pre-COVID vaccination and treatment during acute COVID-19 remain uncertain. This study aimed to investigate patient-specific factors associated with long COVID in a large cohort of non-hospitalized adult patients with mild to moderate COVID-19 in Dubai. STUDY DESIGN: Cohort study. METHODS: The study included 28,375 non-hospitalized adult patients diagnosed with mild to moderate COVID-19 between January 1, 2021, and September 31, 2022, in Dubai, who were followed up for 90 days. The presence of long COVID symptoms was documented by physicians during patient visits to the family medicine department. Furthermore, long COVID-related risk factors were collected and analyzed, including patient demographics, comorbidities, pre-COVID vaccination status, and the COVID-related treatments received during the acute phase of the illness. Cox proportional hazard models were applied for the statistical analysis. RESULTS: Among the cohort, 2.8% of patients experienced long COVID symptoms during the 90-day follow-up. Patients with long COVID tended to be younger, female, and of Caucasian race. Common symptoms included fatigue, muscle pain, respiratory symptoms, abdominal and neurological symptoms, allergic reactions, skin rashes, and hair loss. Risk factors for long COVID were identified as diabetes mellitus, asthma, and Vitamin D deficiency. Females and Caucasians had a higher risk of long COVID during the pre-Omicron period compared to the Omicron period. Pre-COVID vaccination was associated with a reduced risk of long COVID in all patient subgroups. Treatment with favipiravir or sotrovimab during the acute phase of COVID-19 was linked to a decreased risk of long COVID, although favipiravir showed limited effectiveness in the high-risk group. CONCLUSION: This study contributes to the existing knowledge by identifying risk factors for long COVID among non-hospitalized patients and emphasizing the potential benefits of pre-COVID vaccination and timely treatment.


Assuntos
Amidas , COVID-19 , Síndrome Pós-COVID-19 Aguda , Pirazinas , Adulto , Humanos , Feminino , COVID-19/epidemiologia , COVID-19/prevenção & controle , Emirados Árabes Unidos/epidemiologia , SARS-CoV-2 , Estudos de Coortes , Fatores de Risco
13.
Molecules ; 29(7)2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38611871

RESUMO

Oleoylethanolamide (OEA) and palmitoylethanolamide (PEA) are endogenous lipids that act as agonists of the peroxisome proliferator-activated receptor α (PPARα). Recently, an interest in the role of these lipids in malignant tumors has emerged. Nevertheless, the effects of OEA and PEA on human neuroblastoma cells are still not documented. Type I interferons (IFNs) are immunomodulatory cytokines endowed with antiviral and anti-proliferative actions and are used in the treatment of various pathologies such as different cancer forms (i.e., non-Hodgkin's lymphoma, melanoma, leukemia), hepatitis B, hepatitis C, multiple sclerosis, and many others. In this study, we investigated the effect of OEA and PEA on human neuroblastoma SH-SY5Y cells treated with IFNß. We focused on evaluating cell viability, cell proliferation, and cell signaling. Co-exposure to either OEA or PEA along with IFNß leads to increased apoptotic cell death marked by the cleavage of caspase 3 and poly-(ADP ribose) polymerase (PARP) alongside a decrease in survivin and IKBα levels. Moreover, we found that OEA and PEA did not affect IFNß signaling through the JAK-STAT pathway and the STAT1-inducible protein kinase R (PKR). OEA and PEA also increased the phosphorylation of p38 MAP kinase and programmed death-ligand 1 (PD-L1) expression both in full cell lysate and surface membranes. Furthermore, GW6471, a PPARα inhibitor, and the genetic silencing of the receptor were shown to lower PD-L1 and cleaved PARP levels. These results reveal the presence of a novel mechanism, independent of the IFNß-prompted pathway, by which OEA and PEA can directly impair cell survival, proliferation, and clonogenicity through modulating and potentiating the intrinsic apoptotic pathway in human SH-SY5Y cells.


Assuntos
Amidas , Endocanabinoides , Etanolaminas , Neuroblastoma , Ácidos Oleicos , Humanos , Neuroblastoma/tratamento farmacológico , Antígeno B7-H1 , Janus Quinases , PPAR alfa , Inibidores de Poli(ADP-Ribose) Polimerases , Fatores de Transcrição STAT , Transdução de Sinais , Apoptose , Ácidos Palmíticos/farmacologia
14.
Pestic Biochem Physiol ; 200: 105843, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38582603

RESUMO

Isoxazoline is a novel structure with strong potential for controlling agricultural insect pests, but its high toxicity to honeybees limits its development in agriculture. Herein, a series of N-phenylamide isoxazoline derivatives with low honeybee toxicity were designed and synthesized using the intermediate derivatization method. Bioassay results showed that these compounds exhibited good insecticidal activity. Compounds 3b and 3f showed significant insecticidal effects against Plutella xylostella (P. xylostella) with median lethal concentrations (LC50) of 0.06 and 0.07 mg/L, respectively, comparable to that of fluralaner (LC50 = 0.02 mg/L) and exceeding that of commercial insecticide fluxametamide (LC50 = 0.52 mg/L). It is noteworthy that the acute honeybee toxicities of compounds 3b and 3f (LD50 = 1.43 and 1.63 µg/adult, respectively) were significantly reduced to 1/10 of that of fluralaner (LD50 = 0.14 µg/adult), and were adequate or lower than that of fluxametamide (LD50 = 1.14 µg/adult). Theoretical simulation using molecular docking indicates that compound 3b has similar binding modes with fluralaner and a similar optimal docking pose with fluxametamide when binding to the GABA receptor, which may contribute to its potent insecticidal activity and relatively low toxicity to honey bees. This study provides compounds 3b and 3f as potential new insecticide candidates and provides insights into the development of new isoxazoline insecticides exhibiting both high efficacy and environmental safety.


Assuntos
Inseticidas , Mariposas , Abelhas , Animais , Inseticidas/toxicidade , Inseticidas/química , Simulação de Acoplamento Molecular , Insetos , Receptores de GABA/metabolismo , Amidas/toxicidade , Mariposas/metabolismo
15.
Front Endocrinol (Lausanne) ; 15: 1287930, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38577572

RESUMO

Objective: To evaluate the role of foot muscle amide proton transfer weighted (APTw) contrast and tissue rest perfusion in quantifying diabetic foot (DF) infection and its correlation with blood parameters. Materials and methods: With approval from an ethical review board, this study included 40 diabetes mellitus (DM) patients with DF and 31 DM patients without DF or other lower extremity arterial disease. All subjects underwent MRI, which included foot sagittal APTw and coronal arterial spin labeling (ASL) imaging. The normalized MTRasym (3.5 ppm) and the ratio of blood flow (rBF) in rest status of the affected side lesions to the non-affected contralateral side were determined. The inter-group differences of these variables were evaluated. Furthermore, the association between normalized MTRasym (3.5 ppm), rBF, and blood parameters [fasting blood glucose (FBG), glycosylated hemoglobin content, C-reactive protein, neutrophil percentage, and white blood cell count] was explored. Using an ROC curve, the diagnostic capacity of normalized MTRasym (3.5 ppm), BF, and blood biochemical markers in differentiating with or without DF in DM was assessed. Results: In the DF group, MTRasym (3.5 ppm) and BF in lesion and normalized MTRasym (3.5 ppm) were higher than those in the control group (p < 0.05). In addition, correlations were identified between normalized MTRasym (3.5 ppm) and blood parameters, such as C-reactive protein, glycosylated hemoglobin content, FBG, neutrophil ratio, and white blood cell (p < 0.001). Meanwhile, association between BF in lesion and blood parameters, such as C-reactive protein, neutrophil percentage, and FBG (p < 0.01). AUC of normalized MTRasym (3.5 ppm) in identifying with/without DF in patients with DM is 0.986 (95% CI, 0.918-1.00) with the sensitivity of 97.22% and the specificity of 100%. Conclusion: Normalized MTRasym (3.5 ppm) and the BF in lesion may be treated as a safer and more convenient new indicator to evaluate the tissue infection without using a contrast agent, which may be useful in monitoring and preoperatively assessing DF patients with renal insufficiency.


Assuntos
Diabetes Mellitus , Pé Diabético , Humanos , Prótons , Pé Diabético/diagnóstico por imagem , Amidas/química , Proteína C-Reativa , Estudos de Casos e Controles , Hemoglobinas Glicadas , Imageamento por Ressonância Magnética/métodos
16.
Mol Biol Rep ; 51(1): 482, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578512

RESUMO

BACKGROUND: Natural bone grafts are the highly preferred materials for restoring the lost bone, while being constrained of donor availability and risk of disease transmission. As a result, tissue engineering is emerging as an efficacious and competitive technique for bone repair. Bone tissue engineering (TE) scaffolds to support bone regeneration and devoid of aforesaid limitations are being vastly explored and among these the avian eggshell membrane has drawn attention for TE owing to its low immunogenicity, similarity with the extracellular matrix, and easy availability. METHODOLOGY AND RESULTS: In this study, the development of bone ingrowth support system from avian eggshell membrane derived collagen hydrolysates (Col-h) is reported. The hydrolysate, cross-linked with glutaraldehyde, was developed into hydrogels with poly-(vinyl alcohol) (PVA) by freeze-thawing and further characterized with ATR-FTIR, XRD, FESEM. The biodegradability, swelling, mechanical, anti-microbial, and biocompatibility evaluation were performed further for the suitability in bone regeneration. The presence of amide I, amide III, and -OH functional groups at 1639 cm- 1,1264 cm- 1, and 3308 cm- 1 respectively and broad peak between 16°-21° (2θ) in XRD data reinstated the composition and form. CONCLUSIONS: The maximum ratio of Col-h/PVA that produced well defined hydrogels was 50:50. Though all the hydrogel matrices alluded towards their competitive attributes and applicability towards restorative bone repair, the hydrogel with 40:60 ratios showed better mechanical strength and cell proliferation than its counterparts. The prominent E. coli growth inhibition by the hydrogel matrices was also observed, along with excellent biocompatibility with MG-63 osteoblasts. The findings indicate strongly the promising application of avian eggshell-derived Col-h in supporting bone regeneration.


Assuntos
Casca de Ovo , Escherichia coli , Animais , Colágeno/farmacologia , Tecidos Suporte , Engenharia Tecidual/métodos , Hidrogéis , Regeneração Óssea , Amidas
17.
Pestic Biochem Physiol ; 199: 105757, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38458660

RESUMO

Fenhexamid are fungicides that act against plant pathogens by inhibiting sterol biosynthesis. Nonetheless, it can trigger endocrine disruption and promote breast cancer cell growth. In a recent study, we investigated the mechanism underlying the lipid accumulation induced by fenhexamid hydroxyanilide fungicides in 3 T3-L1 adipocytes. To examine the estrogen receptor alpha (ERα)-agonistic effect, ER transactivation assay using the ERα-HeLa-9903 cell line was applied, and fenhexamid-induced ERα agonist effect was confirmed. Further confirmation that ERα-dependent lipid accumulation occurred was provided by treating 3 T3-L1 adipocytes with Methyl-piperidino-pyrazole hydrate (MPP), an ERα-selective antagonist. Fenhexamid mimicked the actions of ERα agonists and impacted lipid metabolism, and its mechanism involves upregulation of the expression of transcription factors that facilitate adipogenesis and lipogenesis. Additionally, it stimulated the expression of peroxisome proliferator-activated receptor (PPARγ), CCAAT/enhancer-binding protein α (C/EBPα), fatty acid synthase (FAS), and sterol regulatory element-binding protein 1 (SREBP1) and significantly elevated the expression of fatty acid-binding protein 4 (FABP4). In contrast, in combination with an ERα-selective antagonist, fenhexamid suppressed the expression of adipogenic/lipogenic transcription factors. These results suggest that fenhexamid affects the endocrine system and leads to lipid accumulation by interfering with processes influenced by ERα activation.


Assuntos
Amidas , Receptor alfa de Estrogênio , Fungicidas Industriais , Camundongos , Animais , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Fungicidas Industriais/toxicidade , Fungicidas Industriais/metabolismo , Adipócitos/metabolismo , Adipogenia , Metabolismo dos Lipídeos , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/farmacologia , Lipídeos , Células 3T3-L1 , PPAR gama/metabolismo
18.
Molecules ; 29(6)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38542826

RESUMO

The pyrimidine ring is present in various biomolecules such as DNA and RNA bases, aminoacids, vitamins, etc. Additionally, many clinically used drugs including methotrexate and risperidone contain the pyrimidine heterocyclic scaffold as well. Pyrimidine derivatives present diverse biological activities including antioxidant and anticancer activities and can be considered as privileged scaffolds in drug discovery for the treatment of various diseases. Piperidine pyrimidine amides have gained significant attention due to their enzymatic inhibitory activity. Based on our experience and ongoing investigation on cinnamic acid derivatives, their hybrids and substituted pteridines acting as lipoxygenase inhibitors, antioxidants, anti-cancer, and anti-inflammatory agents a series of novel piperidine pyrimidine cinnamic acids amides have been designed and synthesized. The novel hybrids were studied for their antioxidant and anti-inflammatory potential. They exhibit moderate antioxidant activity in the DPPH assay which may be related to their bulkiness. Moreover, moderate to good lipid peroxidation inhibition potential was measured. With regards to their lipoxygenase inhibitory activity, however, two highly potent inhibitors out of the nine tested derivatives were identified, demonstrating IC50 values of 10.7 µM and 1.1 µM, respectively. Molecular docking studies to the target enzyme lipoxygenase support the experimental results.


Assuntos
Acrilamidas , Antioxidantes , Antioxidantes/química , Simulação de Acoplamento Molecular , Lipoxigenase/metabolismo , Anti-Inflamatórios/farmacologia , Inibidores de Lipoxigenase/química , Amidas/química , Pirimidinas/farmacologia , Piperidinas , Relação Estrutura-Atividade , Estrutura Molecular
19.
J Agric Food Chem ; 72(12): 6781-6786, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38470138

RESUMO

This Comment critically addresses the article by Gao et al. (Gao, K., et al. J. Agric. Food Chem. 2015, 63, 1067-1075), providing the structural elucidation of three phenolamide dimers (neolignanamides) from the fruits of Lycium barbarum. A more recent article published by Chen et al. (Chen, H., et al. J. Agric. Food Chem. 2023, 71, 11080-11093) incorporates these structures into further research on the bioactivity of these compounds. Although the analytical techniques used by Gao et al. are adequate, in our opinion, the nuclear magnetic resonance (NMR) spectroscopic data have not been interpreted correctly, resulting in incorrect structures for three neolignanamides from the fruits of L. barbarum. In this Comment, an alternative interpretation of the NMR spectroscopic data and the corresponding structures are proposed. The proposed structures feature linkage types that are much more common for neolignanamides than the linkage types in the originally reported structures of these compounds.


Assuntos
Antioxidantes , Lycium , Antioxidantes/química , Lycium/química , Amidas , Frutas/química , Fenóis/química
20.
Bioconjug Chem ; 35(4): 465-471, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38499390

RESUMO

A versatile chemo-enzymatic tool to site-specifically modify native (nonengineered) antibodies is using transglutaminase (TGase, E.C. 2.3.2.13). With various amines as cosubstrates, this enzyme converts the unsubstituted side chain amide of glutamine (Gln or Q) in peptides and proteins into substituted amides (i.e., conjugates). A pleasant surprise is that only a single conserved glutamine (Gln295) in the Fc region of IgG is modified by microbial TGase (mTGase, EC 2.3.2.13), thereby providing a highly specific and generally applicable conjugation method. However, prior to the transamidation (access to the glutamine residue by mTGase), the steric hindrance from the nearby conserved N-glycan (Asn297 in IgG1) must be reduced. In previous approaches, amidase (PNGase F, EC 3.5.1.52) was used to completely remove the N-glycan. However, PNGase F also converts a net neutral asparagine (Asn297) to a negatively charged aspartic acid (Asp297). This charge alteration may markedly change the structure, function, and immunogenicity of an IgG antibody. In contrast, in our new method presented herein, the N-glycan is trimmed by an endoglycosidase (EndoS2, EC 3.2.1.96), hence retaining both the core N-acetylglucosamine (GlcNAc) moiety and the neutral asparaginyl amide. The trimmed glycan also reduces or abolishes Fc receptor-mediated functions, which results in better imaging agents by decreasing nonspecific binding to other cells (e.g., immune cells). Moreover, the remaining core glycan allows further derivatization such as glycan remodeling and dual conjugation. Practical and robust, our method generates conjugates in near quantitative yields, and both enzymes are commercially available.


Assuntos
Glutamina , Glicosídeo Hidrolases , Glutamina/química , Peptídeo-N4-(N-acetil-beta-glucosaminil) Asparagina Amidase , Transglutaminases/metabolismo , Imunoglobulina G/química , Polissacarídeos/química , Amidas
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...