Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 383
Filtrar
1.
ACS Omega ; 9(37): 38686-38695, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39310208

RESUMEN

Porous materials such as isoreticular metal-organic frameworks (IRMOFs) can be applied in several areas that explore the physical adsorption. An area that has gained prominence is fuel gas storage, as it provides the storage of a large amount of gas at low pressure and the purification of combustible gas due to the selectivity of the different chemical environments of its pores. IRMOFs represent an ideal study group due to their wide range of pore sizes resulting from the use of different organic ligands. In this context, exploring IRMOFs that adsorb more efficiently stands out, mainly for optimizing the ligand, pressure, and temperature. This work focused on the adsorption and separation of CH4 and CO2 using various IRMOFs. The results suggest that IRMOF-6 is the most suitable for separation and purification and that enhanced purification occurs when the temperature is reduced and the system pressure is increased. This better performance is associated with the higher adsorption energies for this MOF, with CO2 being higher than CH4, which tends to become even more evident when the system pressure increases.

2.
Molecules ; 29(17)2024 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-39275102

RESUMEN

Four afatinib derivatives were designed and modeled. These derivatives were compared to the known tyrosine-kinase inhibitors in treating Chronic Myeloid Leukemia, i.e., imatinib and ponatinib. The molecules were evaluated through computational methods, including docking studies, the non-covalent interaction index, Electron Localization and Fukui Functions, in silico ADMET analysis, QTAIM, and Heat Map analysis. The AFA(IV) candidate significantly increases the score value compared to afatinib. Furthermore, AFA(IV) was shown to be relatively similar to the ponatinib profile when evaluating a range of molecular descriptors. The addition of a methylpiperazine ring seems to be well distributed in the structure of afatinib when targeting the BCR-ABL enzyme, providing an important hydrogen bond interaction with the Asp381 residue of the DFG-switch of BCR-ABL active site residue and the AFA(IV) new chemical entities. Finally, in silico toxicity predictions show a favorable index, with some molecules presenting the loss of the irritant properties associated with afatinib in theoretical predictions.


Asunto(s)
Afatinib , Proteínas de Fusión bcr-abl , Simulación del Acoplamiento Molecular , Inhibidores de Proteínas Quinasas , Proteínas de Fusión bcr-abl/antagonistas & inhibidores , Proteínas de Fusión bcr-abl/genética , Proteínas de Fusión bcr-abl/química , Afatinib/química , Afatinib/farmacología , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacología , Humanos , Modelos Moleculares , Simulación por Computador , Mutación , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Enlace de Hidrógeno , Antineoplásicos/química , Antineoplásicos/farmacología , Imidazoles/química , Imidazoles/farmacología , Piridazinas
3.
Metabolites ; 14(8)2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39195533

RESUMEN

The association of thyroid function with essential and non-essential amino acids is understudied, despite their common metabolic roles. Thus, our aim was to evaluate the association of thyroid function with the levels of branched-chain amino acids (BCAAs-leucine, isoleucine, and valine) and of alanine in the general population. We utilized data from the São Paulo research center of ELSA-Brasil, a longitudinal population-based cohort study. Thyroid parameters included thyroid stimulating hormone (TSH), free T4 and free T3 levels, and the FT4:FT3 ratio. BCAAs and alanine were analyzed on a fully automated NMR platform. The current analysis included euthyroid participants and participants with subclinical hyperthyroidism and hypothyroidism. We used Pearson's coefficient to quantify the correlation between thyroid-related parameters and amino acids. Linear regression models were performed to analyze whether thyroid parameters were associated with BCAAs and alanine levels. We included 4098 participants (51.3 ± 9.0 years old, 51.5% women) in this study. In the most adjusted model, higher levels of TSH were associated with higher levels of alanine, FT4 levels were inversely associated with isoleucine levels, FT3 levels were statistically significant and positively associated with valine and leucine, and the T3:T4 ratio was positively associated with all amino acids. We observed that subclinical hypothyroidism was positively associated with isoleucine and alanine levels in all models, even after full adjustment. Our findings highlight the association of subclinical hypothyroidism and thyroid-related parameters (including TSH, free T4, free T3, and FT4:FT3 ratio) with BCAAs and alanine. Further studies are needed to explore the mechanisms underlying this association. These insights contribute to our understanding of the influence of thyroid-related parameters on BCAA and alanine metabolism.

4.
Molecules ; 29(12)2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38930825

RESUMEN

The current article reports the investigation of three new Ni(II) complexes with ONS-donor dithiocarbazate ligands: [Ni(L1)PPh3] (1), [Ni(L2)PPh3] (2), and [Ni(L2)Py] (3). Single-crystal X-ray analyses revealed mononuclear complexes with a distorted square planar geometry and the metal centers coordinated with a doubly deprotonated dithiocarbazate ligand and coligand pyridine or triphenylphosphine. The non-covalent interactions were investigated by the Hirshfeld surface and the results revealed that the strongest interactions were π⋅⋅⋅π stacking interactions and non-classical hydrogen bonds C-H···H and C-H···N. Physicochemical and spectroscopic methods indicate the same structures in the solid state and solution. The toxicity effects of the free ligands and Ni(II) complexes were tested on the human breast cancer cell line MCF-7 and non-malignant breast epithelial cell line MCF-10A. The half-maximal inhibitory concentration (IC50) values, indicating that the compounds were potent in inhibiting cell growth, were obtained for both cell lines at three distinct time points. While inhibitory effects were evident in both malignant and non-malignant cells, all three complexes demonstrated lower IC50 values for malignant breast cell lines than their non-malignant counterparts, suggesting a stronger impact on cancerous cell lines. Furthermore, molecular docking studies were performed showing the complex (2) as a promising candidate for further therapeutic exploration.


Asunto(s)
Antineoplásicos , Complejos de Coordinación , Simulación del Acoplamiento Molecular , Níquel , Humanos , Níquel/química , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Ligandos , Complejos de Coordinación/química , Complejos de Coordinación/farmacología , Complejos de Coordinación/síntesis química , Línea Celular Tumoral , Cristalografía por Rayos X , Células MCF-7 , Estructura Molecular , Proliferación Celular/efectos de los fármacos , Diseño de Fármacos
5.
Fitoterapia ; 175: 105975, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38685509

RESUMEN

Baccharin is one of the major compounds found in Brazilian green propolis and its botanical source, Baccharis dracunculifolia. Considering the biological effects of propolis and B. dracunculifolia, this study aims to evaluate the analgesic and anti-inflammatory potential of baccharin. The neurodepressor potential was performed by the open field test, analgesia by mechanical stimulation with Dynamic Plantar Aesthesiometer, and by thermal stimulation with Hargreaves apparatus. In addition, the anti-inflammatory potential was achieved by the paw edema assay, histopathological evaluation, and NF-kB expression. Doses of 2.5, 5, and 10 mg/kg of baccharin were evaluated. After euthanasia, plantar tissue was collected and prepared for histology. As a result, analgesic activity was observed at a dose of 10 mg/kg of baccharin in thermal stimulation under an inflammatory process and anti-inflammatory potential at a dose of 5 mg/kg of baccharin from the second hour in the paw edema test. A decrease in cellular infiltrate and down-modulation of NF-kB, besides the reduction of edema in the histopathology was observed. There was no evidence of kidney and liver toxicity and neurodepressive potential at the doses tested. Thus, baccharin has a promising anti-inflammatory effect possibly associated with antiedematogenic activity by inhibiting mediators such as prostaglandins, inhibiting the migration of polymorphonuclear cells, and modulating NF-kB expression.


Asunto(s)
Analgésicos , Antiinflamatorios , Baccharis , Edema , FN-kappa B , Própolis , Animales , Masculino , Ratas , Analgésicos/farmacología , Antiinflamatorios/farmacología , Antiinflamatorios/aislamiento & purificación , Baccharis/química , Brasil , Edema/tratamiento farmacológico , Edema/inducido químicamente , FN-kappa B/metabolismo , Própolis/farmacología , Ratas Wistar , Tricotecenos
6.
Mycologia ; 116(3): 418-430, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38530332

RESUMEN

In 1895 and 2001, rust fungi affecting Licania trees (Chrysobalanchaceae) in Brazil were described as Uredo licaniae by Hennings in the state of Goiás and as Phakopsora tomentosae by Ferreira et al. in the state of Amazonas, respectively. Recently, a Licania rust fungus collected close to the Amazonian type location sharing symptoms with the former two species was subjected to morphological examinations and molecular phylogenetic analyses using 28S nuc rDNA (ITS2-28S) and cytochrome c oxidase subunit III (CO3) gene sequences. Since the original type specimen of Ph. tomentosae is considered lost, we carefully reviewed the type description and questioned the identity of the telium, which justified the description of the fungus as a Phakopsora species. Furthermore, the additional revision of the type material described by Hennings revealed that Ph. tomentosae is a synonym of U. licaniae. Based on the morphological examinations, disease symptoms, and shared hosts, we concluded that the newly collected material is conspecific with U. licaniae. However, the phylogenetic analyses rejected allocation in Phakopsora and instead assigned the Licania rust fungus in a sister relationship with Austropuccinia psidii (Sphaerophragmiaceae), the causal agent of the globally invasive myrtle rust pathogen. We therefore favored a recombination of U. licaniae (syn. Ph. tomentosae) into Austropuccinia and proposed the new name Austropuccina licaniae for the second species now identified for this genus. The fungus shares conspicuous symptoms with A. psidii, causing often severe infections of growing leaves and shoots that lead to leaf necrosis, leaf shedding, and eventually to the dieback of entire shoots. In view of the very similar symptoms of its aggressively invasive sister species, we briefly discuss the current state of knowledge about A. licaniae and the potential risks, and the opportunity of its identification.


Asunto(s)
Basidiomycota , ADN de Hongos , Filogenia , Enfermedades de las Plantas , Basidiomycota/genética , Basidiomycota/clasificación , Basidiomycota/aislamiento & purificación , Enfermedades de las Plantas/microbiología , ADN de Hongos/genética , Brasil , Análisis de Secuencia de ADN , ARN Ribosómico 28S/genética , ADN Ribosómico/genética , ADN Espaciador Ribosómico/genética , Complejo IV de Transporte de Electrones/genética , Árboles/microbiología
7.
Front Chem ; 12: 1347370, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38361747

RESUMEN

The present work reports the influence of the presence of different ions (Cl-, Br-, NO3 -, or SO4 2-) on the formation and proprieties of Cu(II) complexes with pyridoxal-benzoylhydrazone (PLBHZ). Four new complexes were successfully synthesized, [CuCl2(PLBHZ)] (1), [CuBr2(PLBHZ)] (2), [CuCl(PLBHZ)H2O]⋅NO3⋅H2O (3), and [CuSO4(PLBHZ)H2O]⋅3H2O (4), and characterized by spectroscopic and physicochemical methods. A single-crystal X-ray study reveals the Schiff base coordinated to the metal center tridentate by the ONS-donor system, resulting in distorted square pyramidal coordination geometries. Noncovalent interactions were investigated by 3D Hirshfeld surface analysis by the d norm function, 2D fingerprint plots, and full interaction maps. The ion exchange is important in forming three-dimensional networks with π⋅⋅⋅π stacking interactions and intermolecular hydrogen bonds. The in vitro biological activity of the free ligand and metal complexes was evaluated against Gram-positive and Gram-negative bacterial strains and the free pyridoxal-hydrazone ligand showed higher activity than their Cu(II) complexes. Molecular docking was used to predict the inhibitory activity of the ligand and complexes against Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli bacteria.

8.
Laryngoscope ; 134(5): 2316-2321, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-37997493

RESUMEN

OBJECTIVE: To analyze the effects of androgen therapy on the thyroarytenoid (TA) muscle, expression of androgen receptors (ARs) and hyaluronic acid (HA) concentration in the vocal folds (VFs) of adult female rats. METHODS: Twenty-one adult female Wistar rats were divided into experimental and control groups. The experimental group received weekly intramuscular injections of nandrolone decanoate for 9 weeks. Following euthanasia and dissection of the VFs, histomorphometric analysis of the TA muscle, immunohistochemical evaluation of ARs, and measurement of HA concentration using the ELISA-like fluorimetric method were performed. RESULTS: The experimental group exhibited a significantly larger mean fiber cross-sectional area in the TA muscle compared to the control group (434.3 ± 68.6 µm2 versus 305.7 ± 110.1 µm2; p = 0.029), indicating muscle hypertrophy. There was no significant difference in the number of muscle fibers. The experimental group showed higher expression of ARs in the lamina propria (62.0% ± 30.3% versus 22.0% ± 22.8%; p = 0.046) and in the TA muscle (45.0% ± 22.6% versus 18.3% ± 9.8%; p = 0.024). There was no significant difference in the concentration of HA. CONCLUSION: Exposure of adult female rats to androgen therapy resulted in hypertrophy of the TA muscle and increased expression of ARs in the VFs. The TA muscle seems to be the primary target of testosterone action in the VF, and the up-regulation of ARs might contribute to the persistent deepening of the voice. LEVEL OF EVIDENCE: NA Laryngoscope, 134:2316-2321, 2024.


Asunto(s)
Músculos Laríngeos , Pliegues Vocales , Ratas , Femenino , Animales , Pliegues Vocales/fisiología , Testosterona/farmacología , Andrógenos/farmacología , Ratas Wistar , Membrana Mucosa , Hipertrofia
9.
Ciênc. rural (Online) ; 54(1): e20220658, 2024. ilus, tab
Artículo en Inglés | VETINDEX | ID: biblio-1438065

RESUMEN

This study assessed the efficacy of an intra-articular injection of allogeneic adipose tissue-derived from mesenchymal stem cells (AD-MSCs) for the treatment of hip dysplasia in dogs. The study group included 12 otherwise healthy dogs of different breeds, ages, weights, and degrees of hip dysplasia diagnosed using radiography. An orthopedic assessment was performed on all dogs before and at 30, 60, and 90 days after infusion of AD-MSCs(2 × 106cells). On the same days, each dog's owner answered a questionnaire based on theHelsinkiChronic Pain Index. The data were converted to ordinal data based on the score for each variable, and the Friedman test for multiple comparisons was used to verify the results. Compared with the corresponding values on day 0, orthopedic and gait assessments and owners' reported pain indexes improved over the 90-day observation period. These results suggested that treatment with allogeneic AD-MSCs significantly reduced the clinical signs associated with hip dysplasia during the study period. However, long-term studies are needed to determine the optimal therapeutic protocol for routine clinical use of AD-MSCs in hip dysplasia.


O objetivo deste estudo foi avaliar a eficácia clínica da aplicação intra-articular de células-tronco mesenquimais alógenas derivadas do tecido adiposo (AD-CTM) no tratamento de cães portadores de osteoartrite secundária a displasia do coxofemoral (DCF). Doze cães de ambos os sexos, diferentes raças, idades e peso, portadores de graus variados de DCF comprovada em radiografia e livres de quaisquer outras alterações clínicas ou ortopédicas, foram utilizados no estudo. Todos os cães foram submetidos a avaliação ortopédica nos dias 0, 30, 60 e 90 após aplicação de AD-CTM na dose de 2 x 106. Além disso, os tutores preencheram a um questionário, baseado no Índice de dor crônica de Helsinque (IDCH) nos mesmos intervalos. Em comparação com o dia 0, observou-se melhora significativa na avalição em locomoção e físico-ortopédica assim como na avaliação dos tutores pelo IDCH ao longo dos 90 dias. Os resultados permitem inferir que as AD-CTM alógenas contribuíram significativamente para a redução dos sinais clínicos comumente associados a DCF durante o período de estudo. Entretanto, há necessidade de estudos de longo prazo para melhor determinação de protocolos terapêuticos baseados no uso de AD-CTM na rotina clínica.


Asunto(s)
Animales , Perros , Osteoartritis/veterinaria , Enfermedades del Desarrollo Óseo/veterinaria , Enfermedad Crónica/veterinaria , Enfermedades de los Perros/terapia , Células Madre Mesenquimatosas
10.
ACS Omega ; 8(49): 46830-46840, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38107956

RESUMEN

The amount of polluting gases released into the atmosphere has grown drastically. Among them, it is possible to cite the release of CO2 and CO gases on a large scale as one of the products of the complete and incomplete combustion of petroleum-derived fuels. It is worth noting that the production of energy by burning fossil fuels supplies the energy demand but causes environmental damage, and several studies have addressed the reduction. One of them is using materials with the potential to capture these gases. The experimental and theoretical studies have significant contributions that promote advances in this area. Among the materials investigated, ZnO has emerged, demonstrating the considerable potential for capturing various gases, including CO2 and CO. This work used density functional theory (DFT) and Grand Canonical Monte Carlo Method (GCMC) to investigate the adsorption of CO2 and CO on the surface of Zinc oxide (ZnO) to obtain adsorption isotherms and interaction energy and the interaction nature. The results suggest that CO2 adsorption slightly changed the angle of the O-C-O to values less than 180°. For the CO, its carbon atom interacts simultaneously with Zn and O of the ZnO surface. However, CO interactions have an ionic character with a lower binding energy value than the CO2 interaction. The energies calculated using the PM6 and DFT methods generated results compatible with the experimental values. In applications involving a mixture of these two gases, the adsorption of CO2 should be favored, and there may be inhibition of the adsorption of CO for high CO2 concentrations.

11.
J Chem Phys ; 159(23)2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-38099545

RESUMEN

The electronic properties of SO2 at the surface of a water cluster were investigated by employing a combination of Born-Oppenheimer molecular dynamics and electron propagator theory (EPT). In our work, we utilized a revised version of the Perdew-Burke-Ernzerhof (PBE) exchange-correlation functional, which incorporates empirical corrections for dispersion interactions in line with a recent study of the air-water interface conducted by Ohto et al. [J. Phys. Chem. Lett. 10(17), 4914-4919 (2019)]. Polarization effects induce a significant broadening of the electron binding energy distribution, as predicted by EPT. This broadening can result in a substantial increase in electron affinity, impacting the chemical reactivity of SO2 at the air-water interface, a topic of significant and recent research interest. We discuss the relationship between electron binding energies (EBEs) and the specific connections of SO2 to water. The results indicate that configurations involving an OS⋯H bond tend to yield higher electron affinities compared to complex formation through S⋯OW bonds. Surprisingly, SO2 molecules not bound to water molecules according to a specific criterion may also exhibit higher electron affinities. This feature can be explained by the role played by the polarization field from water molecules. Our best estimate for the HOMO-LUMO (H-L) gap of SO2 at the surface of a water cluster is 11.6 eV. Very similar H-L gaps are predicted for isolated and micro-solvated SO2. Fukui functions for the gas phase, and the micro-solvated SO2-H2O complex supports the view that the LUMO is predominantly localized on the SO2 moiety.

12.
Mycologia ; 115(6): 802-812, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37862601

RESUMEN

Two Cerrado rust fungi, Phakopsora rossmaniae and Aplopsora hennenii, described in 1993 and 1995 and originally assigned to families Phakopsoraceae and Ochropsoraceae, respectively, were subjected to molecular phylogenetic analyses using fragments of the nuc 28S and 18S rDNA and mitochondrial cytochrome c oxidase subunit 3 (CO3) gene. Although both taxa were morphologically well placed in their original genera, they were shown to belong in a strongly supported new lineage within the Raveneliineae distant from the Phakopsoraceae and Ochropsoraceae. Therefore, we properly treated this lineage as the new genus Cerradopsora now harboring C. rossmaniae (type species) and C. hennenii. However, this novel phakopsoroid genus remains in uncertain familial position without support to be included in any of the families that share space within the Raveneliineae.


Asunto(s)
Basidiomycota , Humanos , Filogenia , ADN de Hongos/genética , Basidiomycota/genética , ADN Ribosómico/genética
13.
Int J Mol Sci ; 24(20)2023 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-37894797

RESUMEN

Understanding the role of 3CLpro protease for SARS-CoV-2 replication and knowing the potential of flavonoid molecules like rutin, myricetin, and baicalein against 3CLpro justify an investigation into their inhibition. This study investigates possible bonds and reactivity descriptors of rutin, myricetin, and baicalein through conformational and electronic properties. Density functional theory was used to determine possible interactions. Analyses were carried out through the molecular electrostatic potential, electron localization function, Fukui function descriptors based on frontier orbitals, and non-covalent interactions. A docking study was performed using a resolution of 1.55 Å for 3CLpro to analyze the interactions of rutin, myricetin, and baicalein. Scores of structures showed that rutin is the best ligand, followed by myricetin and baicalein. Docking studies showed that baicalein and rutin can establish effective interactions with residues of the catalytic dyad (Cys145 and His41), but just rutin forms a hydrogen bond. Myricetin, in turn, could not establish an effective interaction with Cys145. Baicalein interaction arose with active residues such as Arg188, Val186, Gln189, and Gln192. Interactions of rutin and myricetin with Arg188 and Gln189 were also found. A critical interaction was observed only for rutin with the hydroxyls of ring A with His41, and also for Cys145 with rings B and C, which is probably related to the highest score of rutin.


Asunto(s)
Flavanonas , Rutina , Flavonoides/farmacología , Simulación del Acoplamiento Molecular , Inhibidores de Proteasas/química , Simulación de Dinámica Molecular , Antivirales/farmacología
14.
Molecules ; 28(18)2023 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-37764431

RESUMEN

The present study employs high-level ab initio calculations to investigate the structure, vibrational frequencies, and electronic properties of H2S∙∙∙SO2. The analysis of vibrational frequencies reveals an intramolecular vibrational energy transfer phenomenon, where energy from the stretching modes of H2S is transferred to the ν1s mode of SO2. At the CCSD(T)/aug-cc-pVQZ level, the interaction energy between H2S and SO2 is predicted to be 2.78 kcal/mol. Electron propagator theory calculations yield a HOMO-LUMO gap of 8.24 eV for H2S∙∙∙SO2. Furthermore, by utilizing ab initio results for the adiabatic ionization energy and electron affinity, the electrophilicity of H2S∙∙∙SO2 is estimated to be 2.01 eV. This value is similar to the electrophilicity of SO2, suggesting comparable reactivity and chemical behavior. The non-covalent interaction (NCI) analysis of the H2S∙∙∙SO2 complex emphasizes the significant contribution of non-covalent van der Waals interactions in its energetic stabilization.

15.
Parasit Vectors ; 16(1): 336, 2023 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-37752574

RESUMEN

BACKGROUND: This study describes the effectiveness of a novel active pharmaceutical ingredient, fluralaner (isoxazoline class), against important ectoparasites infesting cattle in Brazil. METHODS: A total of 13 studies involving a 5% fluralaner-based pour-on formulation (Exzolt 5%; further referred to as Exzolt) were conducted. Specifically, the effectiveness of this formulation was studied against Rhipicephalus microplus (6 studies), Cochliomyia hominivorax larvae (4 studies), Dermatobia hominis larvae (1 study) and Haematobia irritans flies (2 studies). RESULTS: The therapeutic efficacy of Exzolt was found to exceed 98% at 4 days post treatment (DPT), while persistent efficacy (> 90% efficacy) against repeated infestations of R. microplus was observed for up to 79 DPT. In field studies, ≥ 98% therapeutic efficacy was demonstrated at all study sites by 7 DPT, and a persistent efficacy (> 90% efficacy) was observed for 42, 49 or 56 DPT. Exzolt prevented C. hominivorax eggs from developing to the larval stage, thus mitigating the development of myiasis in cattle naturally and artificially infested with this screworm. The efficacy of Exzolt against D. hominis larvae was 98% at 3 DPT, while persistent efficacy (> 90% effectiveness) was found to last for up to 70 DPT. Against H. irritans, Exzolt showed therapeutic efficacy (≥ 90%) within the first day of treatment at both study sites, while persistent efficacy (≥ 90%) was observed for 7 DPT at one site and for 21 DPT at the other site. CONCLUSIONS: Overall, the results from these studies confirm that Exzolt is therapeutically efficacious against the most important ectoparasites infesting cattle in Brazil. The novel active pharmaceutical ingredient, fluralaner, provides a new treatment option for farmers to control cattle ectoparasites, especially where there is resistance to other chemical classes. In addition, an effective control of ectoparasites will improve overall cattle health and well-being as well as production.


Asunto(s)
Enfermedades de los Bovinos , Muscidae , Infestaciones por Garrapatas , Animales , Bovinos , Brasil/epidemiología , Óvulo , Larva , Enfermedades de los Bovinos/tratamiento farmacológico , Enfermedades de los Bovinos/prevención & control , Enfermedades de los Bovinos/parasitología , Preparaciones Farmacéuticas , Infestaciones por Garrapatas/tratamiento farmacológico , Infestaciones por Garrapatas/prevención & control , Infestaciones por Garrapatas/veterinaria
16.
Int J Mol Sci ; 24(14)2023 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-37511201

RESUMEN

The current research describes the synthesis and characterization of 2-acetylpyridine N(4)-cyclohexyl-thiosemicarbazone ligand (HL) and their two metal complexes, [Au(L)Cl][AuCl2] (1) and [Pd(L)Cl]·DMF (2). The molecular structures of the compounds were determined by physicochemical and spectroscopic methods. Single crystal X-ray diffraction was employed in the structural elucidation of the new complexes. The complexes showed a square planar geometry to the metal center Au(III) and Pd(II), coordinated with a thiosemicarbazone molecule by the NNS-donor system and a chloride ion. Complex (1) also shows the [AuCl2]- counter-ion in the asymmetric unit, and complex (2) has one DMF solvent molecule. These molecules play a key role in the formation of supramolecular structures due to different interactions. Noncovalent interactions were investigated through the 3D Hirshfeld surface by the dnorm function and the 2D fingerprint plots. The biological activity of the compounds was evaluated in vitro against the human glioma U251 cells. The cytotoxicity results revealed great antitumor activity in complex (1) compared with complex (2) and the free ligand. Molecular docking simulations were used to predict interactions and properties with selected proteins and DNA of the synthesized compounds.


Asunto(s)
Antineoplásicos , Complejos de Coordinación , Tiosemicarbazonas , Humanos , Simulación del Acoplamiento Molecular , Tiosemicarbazonas/farmacología , Tiosemicarbazonas/química , Paladio/farmacología , Paladio/química , Oro/química , Ligandos , Complejos de Coordinación/farmacología , Complejos de Coordinación/química , Estructura Molecular , Cristalografía por Rayos X , Antineoplásicos/química
17.
Arch Endocrinol Metab ; 67(6): e000644, 2023 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-37364146

RESUMEN

Objective: The risk of malignancy and diagnostic accuracy of fine-needle aspiration biopsy (FNAB) of thyroid nodules (TN) with diameters ≥ 3-4 cm remains controversial. However, some groups have indicated surgical treatment in these patients regardless of the FNAB results. We aimed to evaluate the diagnostic accuracy of the FNAB in systematically resected ≥4 cm TN and if the risk of malignancy is higher in these patients. Subjects and methods: We retrospectively evaluated 138 patients (142 nodules) with TN with diameters ≥4 cm who underwent thyroidectomy. Results: The FNAB results were nondiagnostic/unsatisfactory (ND/UNS) in 2.1% of the cases and benign in 51.4%. They indicated atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) in 23.9% of cases, follicular neoplasia/suspicious for a follicular neoplasm (FN/SFN) in 9.2%, suspicion of malignancy (SUS) in 8.5%, and malignant in 4.9%. The histopathological analysis after thyroidectomy revealed a thyroid cancer rate of 100% in the FNABs classified as malignant, 33.3% in SUS cases, 7.7% in FN/SFN, 17.6% in AUS/FLUS, and 4.1% in benign FNABs. None of the ND/UNS FNABs were malignant. The global malignancy diagnosis was 14.8% (n = 21). However, the rate of false negatives for FNAB was low (4.1%). Conclusion: We showed that the risk of malignancy in nodules with diameters ≥4 cm was higher compared to the risk of thyroid cancer in TN in general. However, we found a low rate of false-negative cytological results; therefore, our data do not justify the orientation of routine resection for these larger nodules.


Asunto(s)
Adenocarcinoma Folicular , Neoplasias de la Tiroides , Nódulo Tiroideo , Humanos , Nódulo Tiroideo/diagnóstico , Nódulo Tiroideo/cirugía , Nódulo Tiroideo/patología , Biopsia con Aguja Fina/métodos , Estudios Retrospectivos , Neoplasias de la Tiroides/diagnóstico , Neoplasias de la Tiroides/cirugía , Neoplasias de la Tiroides/patología , Tiroidectomía , Adenocarcinoma Folicular/diagnóstico , Adenocarcinoma Folicular/cirugía
18.
Einstein (Sao Paulo) ; 21: eAO0033, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37075458

RESUMEN

OBJECTIVE: The levonorgestrel intrauterine system treatment prevents 67.7% of surgeries in patients with heavy menstrual bleeding and enlarged uteri. To evaluate the effectiveness of the levonorgestrel intrauterine system in the treatment of patients with heavy menstrual bleeding and an enlarged uterus and to compare satisfaction and its complications with hysterectomy. METHODS: This was a comparative cross-sectional observational study of women with heavy menstrual bleeding and an enlarged uterus. Sixty-two women were treated and followed up for four years. Insertion of the levonorgestrel intrauterine system was performed in Group 1, and laparoscopic hysterectomy was performed in Group 2. RESULTS: In Group 1 (n=31), 21 patients (67.7%) showed improvement in the bleeding pattern, and 11 patients (35.5%) had amenorrhea. Five patients (16.1%) remained with heavy bleeding and were considered to have experienced treatment failure. There were seven expulsions (22.6%); in five patients, bleeding remained heavy, but in two patients the bleeding returned to that of normal menstruation. No relationship was found between treatment failure and greater hysterometries (p=0.40) or greater uterine volumes (p=0.50), whereas expulsion was greater in uteri with smaller hysterometries (p=0.04). There were 13 (21%) complications, seven (53.8%) in the group that underwent insertion of the levonorgestrel intrauterine system (all were device expulsions), and six (46.2%) in the surgical group, which were the most severe ones (p=0.76). Regarding satisfaction, 12 patients (38.7%) were dissatisfied with the levonorgestrel intrauterine system and one (3.23%) was dissatisfied with the surgical treatment (p=0.00). CONCLUSION: Treatment with the levonorgestrel intrauterine system in patients with heavy menstrual bleeding and an enlarged uterus was effective, and when compared with laparoscopic hysterectomy, it had a lower rate of satisfaction and the same rate of complications, although less severe.


Asunto(s)
Laparoscopía , Menorragia , Humanos , Femenino , Levonorgestrel/uso terapéutico , Menorragia/tratamiento farmacológico , Menorragia/cirugía , Estudios Transversales , Útero/cirugía , Histerectomía
19.
J Mol Model ; 29(4): 93, 2023 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-36905478

RESUMEN

Anthocyanidins, leucoanthocyanidins, and flavonols are natural compounds mainly known due to their reported biological activities, such as antiviral, antifungal, anti-inflammatory activities, and antioxidant activity. In the present study, we performed a comparative structural, conformational, electronic, and nuclear magnetic resonance analysis of the reactivity of the chemical structure of primary anthocyanidins, leucoanthocyanidins, and flavonoids. We focused our analysis on the following molecular questions: (i) differences in cyanidin catechols ( +)-catechin, leucocyanidin, and quercetin; (ii) the loss of hydroxyl presents in the R1 radical of leucoanthocyanidin in the functional groups linked to C4 (ring C); and (iii) the electron affinity of the 3-hydroxyl group (R7) in the flavonoids delphinidin, pelargonidin, cyanidin, quercetin, and kaempferol. We show unprecedented results for bond critical point (BCP) of leucopelargonidin and leucodelphirinidin. The BCP formed between hydroxyl hydrogen (R2) and ketone oxygen (R1) of kaempferol has the same degrees of covalence of quercetin. Kaempferol and quercetin exhibited localized electron densities between hydroxyl hydrogen (R2) and ketone oxygen (R1). Global molecular descriptors showed quercetin and leucocyanidin are the most reactive flavonoids in electrophilic reactions. Complementary, anthocyanidins are the most reactive in nucleophilic reactions, while the smallest gap occurs in delphinidin. Local descriptors indicate that anthocyanidins and flavonols are more prone to electrophilic attacks, while in leucoanthocyanidins, the most susceptible to attack are localized in the ring A. The ring C of anthocyanidins is more aromatic than the same found in flavonols and leucoanthocyanidins. METHODS: For the analysis of the molecular properties, we used the DFT to evaluate the formation of the covalent bonds and intermolecular forces. CAM-B3LYP functional with the def2TZV basis set was used for the geometry optimization. A broad analysis of quantum properties was performed using the assessment of the molecular electrostatic potential surface, electron localization function, Fukui functions, descriptors constructed from frontier orbitals, and nucleus independent chemical shift.


Asunto(s)
Antocianinas , Flavonoles , Flavonoles/química , Antocianinas/química , Quercetina/química , Quempferoles/química , Flavonoides/química , Hidrógeno/química , Oxígeno
20.
Front Mol Biosci ; 10: 1146820, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36968279

RESUMEN

In the search for new metal complexes with antitumor potential, two dithiocarbazate ligands derived from 1,1,1-trifluoro-2,4-pentanedione (H2L1) and (H2L2) and four Ni(II) complexes, [Ni(L1)PPh3] (1), [Ni(L1)Py] (2), [Ni(L2)PPh3] (3), and [Ni(L2)Py] (4), were successfully synthesized and investigated by physical-chemistry and spectroscopic methods. The crystal structure of the H2L1 and the Ni(II) complexes has been elucidated by single-crystal X-ray diffraction. The obtained structure from H2L1 confirms the cyclization reaction and formation of the pyrazoline derivative. The results showed square planar geometry to the metal centers, in which dithiocarbazates coordinated by the ONS donor system and a triphenylphosphine or pyridine molecule complete the coordination sphere. Hirshfeld surface analysis by d norm function was investigated and showed π-π stacking interactions upon the molecular packing of H2L1 and non-classical hydrogen bonds for all compounds. Fingerprint plots showed the main interactions attributed to H⋅H C⋅H, O⋅H, Br⋅H, and F⋅H, with contacts contributing between 1.9% and 38.2%. The mass spectrometry data indicated the presence of molecular ions [M + H]+ and characteristic fragmentations of the compounds, which indicated the same behavior of the compounds in solution and solid state. Molecular docking simulations were studied to evaluate the properties and interactions of the free dithiocarbazates and their Ni(II) complexes with selected proteins and DNA. These results were supported by in vitro cytotoxicity assays against four cancer cell lines, showing that the synthesized metal complexes display promising biological activity.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA