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1.
Planta Med ; 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39159664

RESUMO

Withanolides are steroidal lactones commonly found in plants of the Solanaceae family that have significant medicinal value. In this study, three withanolides extracted from Iochroma arborescens leaves were isolated and characterized. These included withaphysalin F (3: ) and two newly identified epimeric compounds: 18R- and 18S-O-methyl-withaphysalin F (1: and 2: ). Their structures were elucidated by NMR, IR, MS, CD, and X-ray diffraction analysis, and their potential against cell proliferation and migration was investigated. The cytotoxic assay revealed activity against different tumor and non-tumor cell lines. (18S)-O-methyl-withaphysalin F (2: ) presented cell death effects after at least 6 hours of exposure. MDA-MB-231 cells were exposed to 0.06 and 0.6 µM of (18S)-O-methyl-withaphysalin F (2: ), and reductions in cell adhesion, migration, and clonogenicity were observed. Morphological analysis revealed negative regulation in filopodia, salience, and roughness, as well as alterations in cellular microarchitecture. These results provide clues as to the effects of (18S)-O-methyl-withaphysalin F (2: ), allowing new molecular modifications to improve potency and selectivity and increase our antineoplastic arsenal.

2.
Plant Cell Physiol ; 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37756637

RESUMO

MSH1 is an organellar targeted protein that obstructs ectopic recombination and the accumulation of mutations in plant organellar genomes. MSH1 also modulates the epigenetic status of nuclear DNA, and its absence induces a variety of phenotypic responses. MSH1 is a member of the MutS family of DNA mismatch repair proteins but harbors an additional GIY-YIG nuclease domain that distinguishes it from the rest of this family. How MSH1 hampers recombination and promotes fidelity in organellar DNA inheritance is unknown. Here, we elucidate its enzymatic activities by recombinantly expressing and purifying full-length MSH1 from Arabidopsis thaliana (AtMSH1). AtMSH1 is a metalloenzyme that shows a strong binding affinity for displacement loops (D-loops). The DNA binding abilities of AtMSH1 reside in its MutS domain and not in its GIY-YIG domain, which is the ancillary nickase of AtMSH1. In the presence of divalent metal ions, AtMSH1 selectively executes multiple incisions at D-loops, but not other DNA structures including Holliday junctions or dsDNA, regardless of the presence or absence of mismatches. The selectivity of AtMSH1 to dismantle D-loops supports the role of this enzyme in preventing recombination between short repeats. Our results suggest that plant organelles have evolved novel DNA repair routes centered around the anti-recombinogenic activity of MSH1.

3.
Molecules ; 28(24)2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38138548

RESUMO

In this paper, novel mixed Tutton salts with the chemical formulas K2Mn0.03Ni0.97(SO4)2(H2O)6 and K2Mn0.18Cu0.82(SO4)2(H2O)6 were synthesized and studied as compounds for thermochemical heat storage potential. The crystallographic structures of single crystals were determined by X-ray diffraction. Additionally, a comprehensive computational study, based on density functional theory (DFT) calculations and Hirshfeld surface analysis, was performed to calculate structural, electronic, and thermodynamic properties of the coordination complexes [MII(H2O)6]2+ (MII = Mn, Ni, and Cu), as well as to investigate intermolecular interactions and voids in the framework. The axial compressions relative to octahedral coordination geometry observed in the crystal structures were correlated and elucidated using DFT investigations regarding Jahn-Teller effects arising from complexes with different spin multiplicities. The spatial distributions of the frontier molecular orbital and spin densities, as well as energy gaps, provided further insights into the stability of these complexes. Thermogravimetry, differential thermal analysis, and differential scanning calorimetry techniques were also applied to identify the thermal stability and physicochemical properties of the mixed crystals. Values of dehydration enthalpy and storage energy density per volume were also estimated. The two mixed sulfate hydrates reported here have low dehydration temperatures and high energy densities. Both have promising thermal properties for residential heat storage systems, superior to the Tutton salts previously reported.

4.
J Biol Inorg Chem ; 25(3): 419-428, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32172453

RESUMO

The cis-[Ru(bpy)2(Met)](PF6)2 complex, where Met = L-methionine and bpy = 2,2'-bipyridine, was prepared and fully characterized. This complex was subjected to blue and green light photolysis (453 and 505 nm, respectively) in aqueous solution, leading to the release of methionine and formation of the cis-[Ru(bpy)2(H2O)2]2+ ion. This latter photoproduct was shown to subsequently interact with DNA, while DNA photocleavage was noticed. In agreement with these reactivities, this compound exhibited an exciting antibacterial action, particularly against Gram-positive bacteria Staphylococcus aureus and Staphylococcus epidermidis, which was enhanced upon blue light irradiation. Altogether, these results showed that our strategy was successful in producing light-triggered DNA-binding agents with pharmacological potential and a likely blocking reagent for efficient peptide chemistry formation.


Assuntos
Antibacterianos/farmacologia , Complexos de Coordenação/farmacologia , Metionina/farmacologia , Rutênio/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus epidermidis/efeitos dos fármacos , Animais , Antibacterianos/síntese química , Antibacterianos/química , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , DNA/efeitos dos fármacos , Clivagem do DNA , Luz , Masculino , Metionina/química , Testes de Sensibilidade Microbiana , Processos Fotoquímicos , Rutênio/química , Salmão , Espermatozoides/química
5.
J Nat Prod ; 82(7): 1831-1838, 2019 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-31313922

RESUMO

Salinaphthoquinones A-E (1-5) were isolated from a marine Salininispora arenicola strain, recovered from sediments of the St. Peter and St. Paul Archipelago, Brazil. The structures of the compounds were elucidated using a combination of spectroscopic (NMR, IR, HRESIMS) data, including single-crystal X-ray diffraction analysis. A plausible biosynthetic pathway for 1-5 is proposed. Compounds 1 to 4 displayed moderate activity against Staphylococcus aureus and Enterococcus faecalis with MIC values of 125 to 16 µg/mL.


Assuntos
Antibacterianos/farmacologia , Sedimentos Geológicos/química , Micromonosporaceae/química , Naftoquinonas/farmacologia , Água do Mar/química , Antibacterianos/química , Brasil , Sedimentos Geológicos/microbiologia , Estrutura Molecular , Naftoquinonas/química , Água do Mar/microbiologia
7.
AAPS PharmSciTech ; 19(3): 1468-1476, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29464593

RESUMO

Albendazole, an effective broad-spectrum anthelmintic agent, showed unpredictable therapeutic response caused by poor water solubility and slow dissolution rate. Then, novel binary and multicomponent supramolecular systems of two different solid forms of albendazole (I and II) with maltodextrin alone or with glutamic acid were studied as an alternative to improve the oral bioavailability of albendazole. The interactions and effects on the properties of albendazole were studied in solution and solid state. The solid systems were characterized using Raman and Fourier transform-infrared spectroscopy, thermal analysis, powder X-ray diffraction, and scanning electron microscopy. The solubility measurements, performed in aqueous and simulated gastric fluid, showed that albendazole (form II) was the most soluble form, while its supramolecular systems showed the highest solubility in simulated gastric fluid. On the other hand, the dissolution profiles of binary and multicomponent systems in simulated gastric fluid displayed pronounced increments of the dissolved drug and a faster dissolution rate compared to those of free albendazole forms. Thus, these supramolecular structures constitute an interesting alternative to improve the physicochemical properties of albendazole, with potential application for the preparation of pharmaceutical oral formulations.


Assuntos
Albendazol/química , Anti-Helmínticos/química , Ácido Glutâmico/química , Polissacarídeos/química , Albendazol/administração & dosagem , Anti-Helmínticos/administração & dosagem , Suco Gástrico , Solubilidade
8.
J Mol Recognit ; 30(11)2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28675505

RESUMO

Supramolecular interactions between ß-lapachone (ß-lap) and cyclodextrins (CDs) were investigated by isothermal titration calorimetry. The most favorable host: guest interaction was characterized using X-ray powder diffraction (XRD), differential scanning calorimetry and thermogravimetry (DSC/TG), spectroscopy (FT-IR), spectroscopy (2D ROESY) nuclear magnetic resonance (NMR), and molecular modeling. Phase solubility diagrams showed ß-, HP-ß-, SBE-ß-, γ-, and HP-γ-CDs at 1.5% (w/w) allowed an increase in apparent solubility of ß-lap with enhancement factors of 12.0, 10.1, 11.8, 2.4, and 2.2, respectively. ß-lap has a weak interaction with γ- and HP-γ-CDs and tends to interact more favorably with ß-CD and its derivatives, especially SBE-ß-CD (K = 4160 M-1 ; ΔG = -20.66 kJ·mol-1 ). Thermodynamic analysis suggests a hydrophobic interaction associated with the displacement of water from the cavity of the CD by the ß-lap. In addition, van der Waals forces and hydrogen bonds were responsible for the formation of complexes. Taken together, the results showed intermolecular interactions between ß-lap and SBE-ß-CD, thereby confirming the formation of the inclusion complex. Molecular docking results showed 2 main orientations in which the interaction of benzene moiety at the wider rim of the SBE-ß-CD is the most stable (average docking energy of -7.0 kcal/mol). In conclusion, ß-lap:SBE-ß-CD is proposed as an approach for use in drug delivery systems in cancer research.


Assuntos
Calorimetria/métodos , Ciclodextrinas/química , Modelos Moleculares , Naftoquinonas/química , Varredura Diferencial de Calorimetria , Entropia , Cinética , Simulação de Acoplamento Molecular , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Difração de Raios X
9.
Pituitary ; 20(4): 422-429, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28275992

RESUMO

PURPOSE: Follow-up guidelines are needed to assess quality of care and to ensure best long-term outcomes for patients with Cushing's disease (CD). The purpose of this study was to assess agreement by experts on recommended follow-up intervals for CD patients at different phases in their treatment course. METHODS: The RAND/UCLA modified Delphi process was used to assess expert consensus. Eleven clinicians who regularly manage CD patients rated 79 hypothetical patient scenarios before and after ("second round") an in-person panel discussion to clarify definitions. Scenarios described CD patients at various time points after treatment. For each scenario, panelists recommended follow-up intervals in weeks. Panel consensus was assigned as follows: "agreement" if no more than two responses were outside a 2 week window around the median response; "disagreement" if more than two responses were outside a 2 week window around the median response. Recommendations were developed based on second round results. RESULTS: Panel agreement was 65.9% before and 88.6% after the in-person discussion. The panel recommended follow-up within 8 weeks for patients in remission on glucocorticoid replacement and within 1 year of surgery; within 4 weeks for patients with uncontrolled persistent or recurrent disease; within 8-24 weeks in post-radiotherapy patients controlled on medical therapy; and within 24 weeks in asymptomatic patients with stable plasma ACTH concentrations after bilateral adrenalectomy. CONCLUSIONS: With a high level of consensus using the Delphi process, panelists recommended regular follow-up in most patient scenarios for this chronic condition. These recommendations may be useful for assessment of CD care both in research and clinical practice.


Assuntos
Hipersecreção Hipofisária de ACTH/tratamento farmacológico , Hipersecreção Hipofisária de ACTH/cirurgia , Adrenalectomia , Hormônio Adrenocorticotrópico/sangue , Glucocorticoides/uso terapêutico , Humanos , Hipersecreção Hipofisária de ACTH/sangue , Hipófise/efeitos dos fármacos , Hipófise/cirurgia
10.
Endocr Pract ; 23(8): 962-970, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28614003

RESUMO

OBJECTIVE: Cushing disease (CD) results from excessive exposure to glucocorticoids caused by an adrenocorticotropic hormone-secreting pituitary tumor. Inadequately treated CD is associated with significant morbidity and elevated mortality. Multicenter data on CD patients treated in routine clinical practice are needed to assess treatment outcomes in this rare disorder. The study purpose was to describe the burden of illness and treatment outcomes for CD patients. METHODS: Eight pituitary centers in four U.S. regions participated in this multicenter retrospective chart review study. Subjects were CD patients diagnosed at ≥18 years of age within the past 20 years. Descriptive statistical analyses were conducted to examine presenting signs, symptoms, comorbidities, and treatment outcomes. RESULTS: Of 230 patients, 79% were female (median age at diagnosis, 39 years; range, 18 to 78 years). Length of follow-up was 0 to 27.5 years (median, 1.9 years). Pituitary adenomas were 0 to 51 mm. The most common presenting comorbidities included hypertension (67.3%), polycystic ovary syndrome (43.5%), and hyperlipidemia (41.5%). Biochemical control was achieved with initial pituitary surgery in 41.4% patients (91 of 220), not achieved in 50.0% of patients (110 of 220), and undetermined in 8.6% of patients (19 of 220). At the end of follow-up, control had been achieved with a variety of treatment methods in 49.1% of patients (110 of 224), not achieved in 29.9% of patients (67 of 224), and undetermined in 21.0% of patients (47 of 224). CONCLUSION: Despite multiple treatments, at the end of follow-up, biochemical control was still not achieved in up to 30% of patients. These multicenter data demonstrate that in routine clinical practice, initial and long-term control is not achieved in a substantial number of patients with CD. ABBREVIATIONS: BLA = bilateral adrenalectomy CD = Cushing disease CS = Cushing syndrome eCRF = electronic case report form MRI = magnetic resonance imaging PCOS = polycystic ovary syndrome.


Assuntos
Adenoma Hipofisário Secretor de ACT/terapia , Adenoma/terapia , Hipersecreção Hipofisária de ACTH/terapia , Inibidores de 14-alfa Desmetilase/uso terapêutico , Adenoma Hipofisário Secretor de ACT/complicações , Adenoma Hipofisário Secretor de ACT/metabolismo , Adenoma Hipofisário Secretor de ACT/patologia , Adenoma/complicações , Adenoma/metabolismo , Adenoma/patologia , Adolescente , Adrenalectomia , Adulto , Idoso , Antineoplásicos/uso terapêutico , Cabergolina , Comorbidade , Inibidores Enzimáticos/uso terapêutico , Ergolinas/uso terapêutico , Feminino , Seguimentos , Hirsutismo/etiologia , Antagonistas de Hormônios/uso terapêutico , Hormônios/uso terapêutico , Humanos , Hiperlipidemias/epidemiologia , Hipertensão/epidemiologia , Hipoglicemiantes/uso terapêutico , Cetoconazol/uso terapêutico , Masculino , Metirapona/uso terapêutico , Pessoa de Meia-Idade , Mifepristona/uso terapêutico , Debilidade Muscular/etiologia , Atrofia Muscular/etiologia , Procedimentos Neurocirúrgicos , Obesidade Abdominal/etiologia , Hipersecreção Hipofisária de ACTH/complicações , Hipersecreção Hipofisária de ACTH/epidemiologia , Hipersecreção Hipofisária de ACTH/metabolismo , Irradiação Hipofisária , Síndrome do Ovário Policístico/epidemiologia , Estudos Retrospectivos , Rosiglitazona , Somatostatina/análogos & derivados , Somatostatina/uso terapêutico , Estrias de Distensão/etiologia , Tiazolidinedionas/uso terapêutico , Resultado do Tratamento , Carga Tumoral , Adulto Jovem
11.
Sensors (Basel) ; 16(7)2016 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-27428966

RESUMO

In general, the use of angle-diversity receivers makes it possible to reduce the impact of ambient light noise, path loss and multipath distortion, in part by exploiting the fact that they often receive the desired signal from different directions. Angle-diversity detection can be performed using a composite receiver with multiple detector elements looking in different directions. These are called non-imaging angle-diversity receivers. In this paper, a comparison of three non-imaging angle-diversity receivers as input sensors of nodes for an indoor infrared (IR) wireless sensor network is presented. The receivers considered are the conventional angle-diversity receiver (CDR), the sectored angle-diversity receiver (SDR), and the self-orienting receiver (SOR), which have been proposed or studied by research groups in Spain. To this end, the effective signal-collection area of the three receivers is modelled and a Monte-Carlo-based ray-tracing algorithm is implemented which allows us to investigate the effect on the signal to noise ratio and main IR channel parameters, such as path loss and rms delay spread, of using the three receivers in conjunction with different combination techniques in IR links operating at low bit rates. Based on the results of the simulations, we show that the use of a conventional angle-diversity receiver in conjunction with the equal-gain combining technique provides the solution with the best signal to noise ratio, the lowest computational capacity and the lowest transmitted power requirements, which comprise the main limitations for sensor nodes in an indoor infrared wireless sensor network.

13.
Neuroepidemiology ; 44(3): 144-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25895443

RESUMO

BACKGROUND: Epilepsy lays an important burden on healthcare systems and society in general. Disability adjusted life years (DALYs) have been developed to compare the burden of this disease both between conditions and between geographical boundaries. With improving data on disease incidence and prevalence in Colombia, we can refine our DALYs-based estimates. METHODS: Using different strategies, including the official healthcare provision database and death certificates, as well as extrapolation from published neuroepidemiologic studies, we estimated the incidence and prevalence by age groups, disease duration and attributable mortality. With this information we calculated DALYs for the year 2012. RESULTS: Overall, it was found that epilepsy was responsible for 0.88% of all deaths in Colombia. A total of 5.25 DALYs per 1,000 person-years are lost due to epilepsy in Colombia, 75% of which (3.91 DALYs) are due to premature mortality, with a higher burden in men (6.12 DALYs) than in women (4.41 DALYs). CONCLUSIONS: We reported new estimations on epilepsy incidence and prevalence by age groups in Colombia and conclude that DALYs lost due to epilepsy in Colombia are almost double the previous figure, mostly because of the underestimation of attributable mortality. With this figure, epilepsy ranks 12th instead of 19th in the list of the most important causes of DALYs lost.


Assuntos
Efeitos Psicossociais da Doença , Epilepsia/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Colômbia/epidemiologia , Bases de Dados Factuais , Epilepsia/mortalidade , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Prevalência , Anos de Vida Ajustados por Qualidade de Vida , Adulto Jovem
14.
J Neurooncol ; 119(2): 235-42, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24980037

RESUMO

Transsphenoidal surgery (TSS) is first-line treatment for Cushing's disease (CD), a devastating disorder of hypercortisolism resulting from overproduction of adrenocorticotropic hormone by a pituitary adenoma. Surgical success rates vary widely and disease may recur years after remission is achieved. Recognizing CD recurrence can be challenging; although there is general acceptance among endocrinologists that patients need lifelong follow-up, there are currently no standardized monitoring guidelines. To begin addressing this need we created a novel, systematic algorithm by integrating information from literature on relapse rates in surgically-treated CD patients and our own clinical experiences. Reported recurrence rates range from 3 to 47 % (mean time to recurrence 16-49 months), emphasizing the need for careful post-surgical patient monitoring. We recommend that patients with post-operative serum cortisol <2 µg/dL (measured 2-3 days post-surgery) be monitored semiannually for 3 years and annually thereafter. Patients with post-operative cortisol between 2 and 5 µg/dL may experience persistent or subclinical CD and should be evaluated every 2-3 months until biochemical control is achieved or additional treatment is initiated. Post-operative cortisol >5 µg/dL often signifies persistent disease and second-line treatment (e.g., immediate repeat pituitary surgery, radiotherapy, and/or medical therapy) may be considered. This follow-up algorithm aims to (a) enable early diagnosis and treatment of recurrent CD, thereby minimizing the detrimental effects of hypercortisolism, and (b) begin addressing the need for standardized guidelines for vigilant monitoring of CD patients treated by TSS, as demonstrated by the reported rates of recurrence.


Assuntos
Monitorização Fisiológica/métodos , Hipersecreção Hipofisária de ACTH/diagnóstico , Algoritmos , Humanos , Hidrocortisona/sangue , Procedimentos Neurocirúrgicos , Hipersecreção Hipofisária de ACTH/sangue , Hipersecreção Hipofisária de ACTH/cirurgia , Período Pós-Operatório , Guias de Prática Clínica como Assunto , Recidiva
15.
Bioanalysis ; 16(14): 711-720, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38940423

RESUMO

Adrenocorticotropic hormone 1-24 (ACTH[1-24]) has a similar effect as endogenous ACTH(1-39) to generate cortisol by targeting the MC2R receptor on the adrenal gland. A new investigational ACTH receptor antagonist drug is being developed to treat diseases of ACTH excess (e.g., Cushing's disease) by binding to the MC2R receptor. Administration of ACTH(1-24) was used in a Phase I clinical study to assess the ability of this drug candidate to suppress the cortisol response to ACTH stimulation. A hybrid immunoaffinity-LCMS assay measuring ACTH(1-24) with a concentration range of 10 to 400 pg/ml was developed to support the study. Consistent and acceptable A&P results were achieved. The assay development and qualification will be discussed.


[Box: see text].


Assuntos
Hormônio Adrenocorticotrópico , Cosintropina , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Hormônio Adrenocorticotrópico/análise , Cosintropina/farmacologia , Cosintropina/análise , Humanos , Cromatografia Líquida/métodos , Hidrocortisona/análise , Espectrometria de Massa com Cromatografia Líquida
16.
J Pharm Sci ; 113(8): 2420-2432, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38705465

RESUMO

Chloraluminium phthalocyanine (ClAlPc) has potential therapeutic effect for the treatment of cancer; however, the molecule is lipophilic and may present self-aggregation which limits its clinical success. Thus, nanocarriers like liposomes can improve ClAlPc solubility, reduce off-site toxicity and increase circulation time. For this purpose, developing suitable liposomes requires the evaluation of different lipid compositions. Herein, we aimed to develop liposomes containing soy phosphatidylcholine (SPC), 1,2-distearoyl-sn-glycero- 3-phosphoethanolamine-N-[amino(polyethylene glycol)-2000] (DSPEPEG2000), cholesterol and oleic acid loaded with ClAlPc using the surface response methodology and the Box-Behnken design. Liposomes with particle size from 110.93 to 374.97 nm and PdI from 0.265 to 0.468 were obtained. The optimized formulation resulted in 69.09 % of ClAlPc encapsulated, with particle size and polydispersity index, respectively, at 153.20 nm and 0.309, providing stability and aggregation control. Atomic force microscopy revealed vesicles in a spherical or almost spherical shape, while the analyzes by Differential Scanning Calorimetry (DSC), Powder X-ray Diffraction (PXRD), and Fourier transform infrared spectroscopy (FTIR) suggested that the drug was adequately incorporated into the lipid bilayer of liposomes, in its amorphous state or molecularly dispersed. In vitro studies conducted in breast cancer cells (4T1) showed that liposome improved phototoxicity compared to the ClAlPc solution. ClAlPc-loaded liposomes also enhanced the production of ROS 3-fold compared to the ClAlPc solution. Finally, confocal microscopy and flow cytometry demonstrated the ability of the liposomes to enter cells and deliver the fluorescent ClAlPc photosensitizer with dose and time-dependent effects. Thus, this work showed that Box-Behnken factorial design was an effective strategy for optimizing formulation development. The obtained ClAlPc liposomes can be applied for photodynamic therapy in breast cancer cells.


Assuntos
Neoplasias da Mama , Indóis , Lipossomos , Compostos Organometálicos , Tamanho da Partícula , Fotoquimioterapia , Fármacos Fotossensibilizantes , Fotoquimioterapia/métodos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Indóis/química , Indóis/administração & dosagem , Feminino , Compostos Organometálicos/química , Compostos Organometálicos/administração & dosagem , Humanos , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/administração & dosagem , Fármacos Fotossensibilizantes/farmacologia , Linhagem Celular Tumoral , Polietilenoglicóis/química , Fosfatidiletanolaminas/química , Fosfatidilcolinas/química , Colesterol/química , Ácido Oleico/química
17.
Eur J Pharm Biopharm ; 201: 114345, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38823540

RESUMO

This study evaluated the synthesis of protic ionic liquids (PILs), 2-hydroxy ethylammonium formate (2-HEAF) and 2-hydroxy ethylammonium acetate (2-HEAA), and their applicability in the crystallization process of the active pharmaceutical ingredient isoniazid (INH) as anti-solvent. Isoniazid is an antibiotic used in the treatment of tuberculosis infections, being used as a first-line chemotherapeutic agent against Mycobacterium tuberculosis. Futhermore, this investigation was conducted in order to evaluate how these PILs can influence the habit, solubility, stability, and therapeutic efficiency of the obtained isoniazid crystals. The 2-HEAF and 2-HEAA PILs were easily formed in reactions between ethanolamine and carboxylic acids (formic or acetic acid), and they have no toxicity against Artemia salina. The PILs were able to crystallize isoniazid, influencing the crystal habit and size. The greatest variations in the hydrogen signals of the NH2 and NH groups of the amine and low variations in the chemical shifts of the hydrogens of the cation of the ethanolamine group from 2-HEAA and 2-HEAF indicate that PILs establish possibly weak interactions with INH. The obtained crystals were amorphous and showed higher solubility in water than standard INH. Moreover, these crystals showed therapeutic efficiency inantimycobacterial activity to inhibit the growth of Mycobacterium tuberculosis. The INH:2-HEAF only degraded 5.1 % (w/w), however, INH:2-HEAA degraded 32.8 % (w/w) after 60 days in an accelerated atmosphere. Then, the 2-HEAA and 2-HEAF were able to crystallize isoniazid, being a new application for these PILs. The used PILs also influenced the characteristics of isoniazid crystals.


Assuntos
Antituberculosos , Cristalização , Líquidos Iônicos , Isoniazida , Solubilidade , Isoniazida/química , Isoniazida/farmacologia , Antituberculosos/farmacologia , Antituberculosos/química , Líquidos Iônicos/química , Animais , Artemia/efeitos dos fármacos , Mycobacterium tuberculosis/efeitos dos fármacos , Química Verde/métodos , Estabilidade de Medicamentos
18.
bioRxiv ; 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39071318

RESUMO

The MutS gene family is distributed across the tree of life and is involved in recombination, DNA repair, and protein translation. Multiple evolutionary processes have expanded the set of MutS genes in plants relative to other eukaryotes. Here, we investigate the origins and functions of these plant-specific genes. Land plants, green algae, red algae, and glaucophytes share cyanobacterial-like MutS1 and MutS2 genes that presumably were gained via plastid endosymbiotic gene transfer. MutS1 was subsequently lost in some taxa, including seed plants, whereas MutS2 was duplicated in Viridiplantae (i.e., land plants and green algae) with widespread retention of both resulting paralogs. Viridiplantae also have two anciently duplicated copies of the eukaryotic MSH6 gene (i.e., MSH6 and MSH7) and acquired MSH1 via horizontal gene transfer - potentially from a nucleocytovirus. Despite sharing the same name, "plant MSH1" is not directly related to the gene known as MSH1 in some fungi and animals, which may be an ancestral eukaryotic gene acquired via mitochondrial endosymbiosis and subsequently lost in most eukaryotic lineages. There has been substantial progress in understanding the functions of MSH1 and MSH6/MSH7 in plants, but the roles of the cyanobacterial-like MutS1 and MutS2 genes remain uncharacterized. Known functions of bacterial homologs and predicted protein structures, including fusions to diverse nuclease domains, provide hypotheses about potential molecular mechanisms. Because most plant-specific MutS proteins are targeted to the mitochondria and/or plastids, the expansion of this family appears to have played a large role in shaping plant organelle genetics.

19.
Int J Pharm ; 661: 124439, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38972520

RESUMO

Liposomes functionalized with monoclonal antibodies offer targeted therapy for cancer, boasting advantages like sustained drug release, enhanced stability, passive accumulation in tumors, and interaction with overexpressed receptors on cancer cells. This study aimed to develop and characterize anti-EGFR immunoliposomes loaded with cabazitaxel and assess their properties against prostate cancer in vitro and in vivo. Using a Box-Behnken design, a formulation with soy phosphatidylcholine, 10% cholesterol, and a 1:20 drug-lipid ratio yielded nanometric particle size, low polydispersity and high drug encapsulation. Immunoliposomes were conjugated with cetuximab through DSPE-PEG-Maleimide lipid anchor. Characterization confirmed intact antibody structure and interaction with EGFR receptor following conjugation. Cabazitaxel was dispersed within the liposomes in the amorphous state, confirmed by solid-state analyses. In vitro release studies showed slower cabazitaxel release from immunoliposomes. Immunoliposomes had enhanced cabazitaxel cytotoxicity in EGFR-overexpressing DU145 cells without affecting non-tumor L929 cells. Cetuximab played an important role to improve cellular uptake in a time-dependent fashion in EGFR-overexpressing prostate cancer cells. In vivo, immunoliposomes led to significant tumor regression, improved survival, and reduced weight loss in xenograft mice. While cabazitaxel induced leukopenia, consistent with clinical findings, histological analysis revealed no evident toxicity. In conclusion, the immunoliposomes displayed suitable physicochemical properties for cabazitaxel delivery, exhibited cytotoxicity against EGFR-expressing prostate cancer cells, with high cell uptake, and induced significant tumor regression in vivo, with manageable systemic toxicity.


Assuntos
Cetuximab , Liberação Controlada de Fármacos , Receptores ErbB , Lipossomos , Neoplasias da Próstata , Taxoides , Ensaios Antitumorais Modelo de Xenoenxerto , Masculino , Animais , Receptores ErbB/imunologia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Humanos , Linhagem Celular Tumoral , Taxoides/administração & dosagem , Taxoides/farmacocinética , Taxoides/farmacologia , Taxoides/química , Cetuximab/administração & dosagem , Camundongos , Camundongos Nus , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Antineoplásicos/química , Polietilenoglicóis/química , Polietilenoglicóis/administração & dosagem , Tamanho da Partícula , Sistemas de Liberação de Medicamentos
20.
J Microencapsul ; 30(8): 787-95, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23631384

RESUMO

Xylan is a biopolymer found in a variety of cell wall plants. Eudragit® S-100 (ES100), a pH-dependent polymer, is used as a coating material in gastroresistant delivery systems. In this study, microparticles based on both polymers were produced by interfacial cross-linking polymerisation and/or spray-drying technique in order to investigate feasibility and stability of the systems. Size and morphology of the microparticles were characterised by optical and SEM while FT-IR, thermal analysis (TG/DTA), and X-ray diffraction (XRD) evaluated the drug-polymer interactions and the thermal behaviour of the systems. FT-IR confirmed the absence of chemical interaction between the polymers. TG/DTA analysis showed a higher stability for spray-dried microparticles and XRD data proved the amorphous feature of both carriers. The results reveal that xylan/ES100 microparticles can be produced by chemical or physico-mechanical ways, the latter being the best option due to the lack of toxic cross-linking agents and easy scale-up.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Portadores de Fármacos/química , Mesalamina/administração & dosagem , Ácidos Polimetacrílicos/química , Xilanos/química , Dessecação , Análise Diferencial Térmica , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
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