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1.
Dis Model Mech ; 16(8)2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37589570

RESUMO

Neural tube defects (NTDs) are the second most common cause of congenital malformations and are often studied in animal models. Loop-tail (Lp) mice carry a mutation in the Vangl2 gene, a member of the Wnt-planar cell polarity pathway. In Vangl2+/Lp embryos, the mutation induces a failure in the completion of caudal neural tube closure, but only a small percentage of embryos develop open spina bifida. Here, we show that the majority of Vangl2+/Lp embryos developed caudal closed NTDs and presented cellular aggregates that may facilitate the sealing of these defects. The cellular aggregates expressed neural crest cell markers and, using these as a readout, we describe a systematic method to assess the severity of the neural tube dorsal fusion failure. We observed that this defect worsened in combination with other NTD mutants, Daam1 and Grhl3. Besides, we found that in Vangl2+/Lp embryos, these NTDs were resistant to maternal folic acid and inositol supplementation. Loop-tail mice provide a useful model for research on the molecular interactions involved in the development of open and closed NTDs and for the design of prevention strategies for these diseases.


Assuntos
Defeitos do Tubo Neural , Cauda , Animais , Camundongos , Modelos Animais de Doenças , Ácido Fólico/farmacologia , Mutação/genética , Defeitos do Tubo Neural/genética , Proteínas de Ligação a DNA , Fatores de Transcrição , Proteínas dos Microfilamentos , Proteínas rho de Ligação ao GTP
2.
J Chem Phys ; 158(24)2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37358222

RESUMO

A new approach for generating Gaussian basis sets is reported and tested for atoms from H to Ne. The basis sets thus calculated, named SIGMA basis sets, range from DZ to QZ sizes and have the same composition per shell as Dunning basis sets but with different treatment of the contractions. The standard SIGMA basis sets and their augmented versions have proven to be very suitable for providing good results in atomic and molecular calculations. The performance of the new basis sets is analyzed in terms of total, correlation, and atomization energies, equilibrium distances, and vibrational frequencies in several molecules, and the results are compared at several computational levels with those obtained with the corresponding Dunning and other basis sets.

3.
J Chem Inf Model ; 61(12): 6012-6023, 2021 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-34762416

RESUMO

Theoretical relationships between the vicinal spin-spin coupling constants (SSCCs) and the χ1 torsion angles have been studied to predict the conformations of protein side chains. An efficient computational procedure is developed to obtain the conformation of dipeptides through theoretical and experimental SSCCs, Karplus equations, and quantum chemistry methods, and it is applied to three aliphatic hydrophobic residues (Val, Leu, and Ile). Three models are proposed: unimodal-static, trimodal-static-stepped, and trimodal-static-trigonal, where the most important factors are incorporated (coupled nuclei, nature and orientation of the substituents, and local geometric properties). Our results are validated by comparison with NMR and X-ray empirical data described in the literature, obtaining successful results on the 29 residues considered. Using out trimodal residue treatment, it is possible to detect and resolve residues with a simple conformation and those with two or three staggered conformers. In four residues, a deeper analysis explains that they do not have a unique conformation and that the population of each conformation plays an important role.


Assuntos
Dipeptídeos , Proteínas , Dipeptídeos/química , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Conformação Proteica , Proteínas/química
4.
Cancers (Basel) ; 13(14)2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34298725

RESUMO

This prospective, phase II study evaluated novel biomarkers as predictors of response to bevacizumab in patients with breast cancer (BC), using serial imaging methods and gene expression analysis. Patients with primary stage II/III BC received bevacizumab 15 mg/kg (cycle 1; C1), then four cycles of neoadjuvant docetaxel doxorubicin, and bevacizumab every 3 weeks (C2-C5). Tumour proliferation and hypoxic status were evaluated using 18F-fluoro-3'-deoxy-3'-L-fluorothymidine (FLT)- and 18F-fluoromisonidazole (FMISO)-positron emission tomography (PET) at baseline, and during C1 and C5. Pre- and post-bevacizumab vascular changes were evaluated using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). Molecular biomarkers were assessed using microarray analysis. A total of 70 patients were assessed for treatment efficacy. Significant decreases from baseline in tumour proliferation (FLT-PET), vascularity, and perfusion (DCE-MRI) were observed during C1 (p ≤ 0.001), independent of tumour subtype. Bevacizumab treatment did not affect hypoxic tumour status (FMISO-PET). Significant changes in the expression of 28 genes were observed after C1. Changes in vascular endothelial growth factor receptor (VEGFR)-2p levels were observed in 65 patients, with a > 20% decrease in VEGFR-2p observed in 13/65. Serial imaging techniques and molecular gene profiling identified several potentially predictive biomarkers that may predict response to neoadjuvant bevacizumab therapy in BC patients.

6.
Brief Bioinform ; 22(5)2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-33569580

RESUMO

In this paper, we show that the combination of NMR theoretical and experimental results can help to solve the molecular structure of peptides, here it is used as an example the residue Leucine-67 in Desulfovibrio vulgaris flavodoxin. We apply a computational protocol based on the leucine amino acid dipeptide, which, using calculated and experimental spin-spin coupling constants, allows us to obtain the conformation of the amino acid side chain. Calculated results show that the best agreement is obtained when three conformers around the lateral chain angle $\chi _1$ are considered or when the dynamic effect in the torsional angles is included. The population of each structure is estimated and analyzed according to the correlation between those two approaches. Independently of the approach, the estimated $\chi _1$ angle in solution is close to the staggered value of -60$^\circ $ and deviates significantly from the average x-ray angle of -90$^\circ $.


Assuntos
Desulfovibrio vulgaris/química , Flavodoxina/química , Leucina/química , Espectroscopia de Ressonância Magnética/métodos , Modelos Moleculares , Sequência de Aminoácidos , Flavodoxina/isolamento & purificação , Peptídeos/química , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Soluções , Solventes/química , Água/química
7.
Dev Dyn ; 250(7): 955-973, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33501723

RESUMO

BACKGROUND: Neural tube (NT) closure is a complex developmental process that takes place in the early stages of embryogenesis and that is a key step in neurulation. In mammals, the process by which the neural plate generates the NT requires organized cell movements and tissue folding, and it terminates with the fusion of the apposed ends of the neural folds. RESULTS: Here we describe how almost identical cellular and molecular machinery is used to fuse the spinal neural folds as that involved in the repair of epithelial injury in the same area of the embryo. For both natural and wound activated closure of caudal neural tissue, hyaluronic acid and platelet-derived growth factor signaling appear to be crucial for the final fusion step. CONCLUSIONS: There seems to be no general wound healing machinery for all tissues but rather, a tissue-specific epithelial fusion machinery that embryos activate when necessary after abnormal epithelial opening.


Assuntos
Células Epiteliais/fisiologia , Tubo Neural/embriologia , Neurulação/fisiologia , Cicatrização/fisiologia , Animais , Fusão Celular , Células Cultivadas , Embrião de Mamíferos , Desenvolvimento Embrionário/fisiologia , Células Epiteliais/citologia , Feminino , Feto/embriologia , Ácido Hialurônico/metabolismo , Masculino , Camundongos , Crista Neural/embriologia , Crista Neural/fisiologia , Placa Neural/embriologia , Placa Neural/fisiologia , Defeitos do Tubo Neural/embriologia , Fator de Crescimento Derivado de Plaquetas/fisiologia , Gravidez
8.
Heliyon ; 6(2): e03394, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32072068

RESUMO

Several studies have been conducted worldwide to develop effective and affordable methods to degrade pharmaceuticals and their metabolites/intermediates/oxidation products found in surface water, wastewater and drinking water. In this work, acetaminophen and its transformation products were successfully degraded in surface water by electrochemical oxidation using stainless steel electrodes. The effect of pH and current density on the oxidation process was assessed and the oxidation kinetics and mechanisms involved were described. Additionally, the results were compared with those obtained in acetaminophen synthetic solutions. It was found that conducting the electrochemical oxidation at 16.3 mA/cm2 and pH 5, good performance of the process was achieved and not only acetaminophen, but also its transformation products were totally degraded in only 7.5 min; furthermore, small number of transformation products were generated. On the other hand, degradation rates of acetaminophen and its transformation products in surface water were much faster (more than 2.5 times) and the reaction times much shorter (more than 4.0 times) than in synthetic solutions at all current densities and pH values evaluated. At pH 3 and pH 5, greater soluble chlorine formation due to the higher HCl amount used to acidify the surface water solutions could enhance the degradation rates of acetaminophen and its transformation products. However, constituents of surface water (ions and solids) could also have an important role on the oxidation process because at pH 9 (non-acidified solutions) the degradation rates were also much greater and the reaction times were much shorter in surface water than in acetaminophen synthetic solutions.

9.
Sci Rep ; 9(1): 20081, 2019 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-31882586

RESUMO

The debate about surgical resection of primary tumor (PT) in de novo metastatic breast cancer (MBC) patients persists. We explored this approach's outcomes in patients included in a retrospective registry, named El Álamo, of breast cancer patients diagnosed in Spain (1990-2001). In this analysis we only included de novo MBC patients, 1415 of whom met the study's criteria. Descriptive, Kaplan-Meier and Cox regression analyses were carried out. Median age was 63.1 years, 49.2% of patients had single-organ metastasis (skin/soft tissue [16.3%], bone [33.8%], or viscera [48.3%]). PT surgery (S) was performed in 44.5% of the cases. S-group patients were younger, had smaller tumors, higher prevalence of bone and oligometastatic disease, and lower prevalence of visceral involvement. With a median follow-up of 23.3 months, overall survival (OS) was 39.6 versus 22.4 months (HR = 0.59, p < 0.0001) in the S- and non-S groups, respectively. The S-group OS benefit remained statistically and clinically significant regardless of metastatic location, histological type, histological grade, hormone receptor status and tumor size. PT surgery (versus no surgery) was associated with an OS benefit suggesting that loco-regional PT control may be considered in selected MBC patients. Data from randomized controlled trials are of utmost importance to confirm these results.


Assuntos
Neoplasias da Mama/patologia , Sistema de Registros , Idoso , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/cirurgia , Feminino , Humanos , Pessoa de Meia-Idade , Metástase Neoplásica , Estudos Retrospectivos , Espanha/epidemiologia
10.
J Comput Aided Mol Des ; 33(11): 997-1008, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31773464

RESUMO

Imbalanced datasets, comprising of more inactive compounds relative to the active ones, are a common challenge in ligand-based model building workflows for drug discovery. This is particularly true for neglected tropical diseases since efforts to identify therapeutics for these diseases are often limited. In this report, we analyze the performance of several undersampling strategies in modeling the Dengue Virus 2 (DENV2) inhibitory activity, as well as the anti-flaviviral activities for the West Nile (WNV) and Zika (ZIKV) viruses. To this end, we build datasets comprising of 1218 (159 actives and 1059 inactives), 1044 (132 actives and 912 inactives) and 302 (75 actives and 227 inactives) molecules with known DENV2, WNV and ZIKV inhibitory activity profiles, respectively. We develop ensemble classifiers for these endpoints and compare the performance of the different undersampling algorithms on external sets. It is observed that data pruning algorithms yield superior performance relative to data selection algorithms. The best overall performance is provided by the one-sided selection algorithm with test set balanced accuracy (BACC) values of 0.84, 0.74 and 0.77 for the DENV2, WNV and ZIKV inhibitory activities, respectively. For the model building, we use the recently proposed GT-STAF information indices, and compare the predictivity of 3 molecular fragmentation approaches: connected subgraphs, substructure and alogp atom types, which are observed to show comparable performance. On the other hand, a combination of indices based on these fragmentation strategies enhances the predictivity of the built ensembles. The built models could be useful for screening new molecules with possible DENV, WNV and ZIKV inhibitory activities. ADMET modelers are encouraged to adopt undersampling algorithms in their workflows when dealing with imbalanced datasets.


Assuntos
Antivirais/farmacologia , Descoberta de Drogas/métodos , Flaviviridae/efeitos dos fármacos , Máquina de Vetores de Suporte , Antivirais/química , Vírus da Dengue/efeitos dos fármacos , Infecções por Flaviviridae/tratamento farmacológico , Humanos , Vírus do Nilo Ocidental/efeitos dos fármacos , Zika virus/efeitos dos fármacos
11.
J Clin Rheumatol ; 25(2): 101-107, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30028809

RESUMO

BACKGROUND/OBJECTIVE: Although mortality rates related with chikungunya (CHIK) outbreaks in Latin America's (LA's) dengue-endemic rural and new urban regions are low, dealing with symptoms and sequelae can both produce a significant burden of disease and diminish quality of life-from many months to years-after the acute phase of the infection, with a significant impact on public and individual health.The aim of this work was to establish Pan-American League of Associations for Rheumatology-Central American, Caribbean and Andean Rheumatology Association (ACCAR) consensus-conference endorsements and recommendations on the diagnosis and treatment of CHIK-related inflammatory arthropathies transmitted by Aedes aegypti and Aedes albopictus in LA. METHODS: Based on the Consensus Development Conference format, a panel of ACCAR rheumatologist voting members (n = 10) took part in this Pan-American League of Associations for Rheumatology initiative. Experts voted from a previous content analysis of the medical literature on CHIK, 4 subsequent topic conferences, and a workshop. Consensus represents the majority agreement (≥80%) achieved for each recommendation. RESULTS: The experts' panel reached 4 overarching principles: (1) CHIK virus (CHIKV) is a re-emergent virus transmitted by 2 species of mosquitoes: A. aegypti and A. albopictus; (2) CHIKV caused massive outbreaks in LA; (3) chronic CHIKV infection produces an inflammatory joint disease that, in some cases, can last for several months to years, and (4) currently, there are no vaccines or antivirals licensed for CHIKV infections. RECOMMENDATIONS: Pan-American League of Associations for Rheumatology-ACCAR achieved 13 endorsements and recommendations on CHIK categorized in 3 groups: (1) epidemiology and clinical manifestations, (2) diagnosis, and (3) treatment, representing the consensus agreement from the panel's members.


Assuntos
Artrite Infecciosa/diagnóstico , Artrite Infecciosa/terapia , Febre de Chikungunya/complicações , Política de Saúde , Reumatologia , Artrite Infecciosa/virologia , Consenso , Humanos , América Latina , Sociedades Médicas
12.
Development ; 145(9)2018 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-29636380

RESUMO

The last stage of neural tube (NT) formation involves closure of the caudal neural plate (NP), an embryonic structure formed by neuromesodermal progenitors and newly differentiated cells that becomes incorporated into the NT. Here, we show in mouse that, as cell specification progresses, neuromesodermal progenitors and their progeny undergo significant changes in shape prior to their incorporation into the NT. The caudo-rostral progression towards differentiation is coupled to a gradual reliance on a unique combination of complex mechanisms that drive tissue folding, involving pulses of apical actomyosin contraction and planar polarised cell rearrangements, all of which are regulated by the Wnt-PCP pathway. Indeed, when this pathway is disrupted, either chemically or genetically, the polarisation and morphology of cells within the entire caudal NP is disturbed, producing delays in NT closure. The most severe disruptions of this pathway prevent caudal NT closure and result in spina bifida. In addition, a decrease in Vangl2 gene dosage also appears to promote more rapid progression towards a neural fate, but not the specification of more neural cells.


Assuntos
Diferenciação Celular , Placa Neural/embriologia , Células-Tronco Neurais/metabolismo , Tubo Neural/embriologia , Via de Sinalização Wnt , Animais , Camundongos , Camundongos Mutantes , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Placa Neural/patologia , Células-Tronco Neurais/patologia , Tubo Neural/patologia , Disrafismo Espinal/epidemiologia , Disrafismo Espinal/genética , Disrafismo Espinal/patologia
13.
J Comput Chem ; 38(8): 530-540, 2017 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-28133839

RESUMO

Ionic liquids (ILs) play a key role in many chemical applications. As regards the theoretical approach, ILs show added difficulties in calculations due to the composition of the ion pair and to the fact that they are liquids. Although density functional theory (DFT) can treat this kind of systems to predict physico-chemical properties, common versions of these methods fail to perform accurate predictions of geometries, interaction energies, dipole moments, and other properties related to the molecular structure. In these cases, dispersion and self-interaction error (SIE) corrections need to be introduced to improve DFT calculations involving ILs. We show that the inclusion of dispersion is needed to obtain good geometries and accurate interaction energies. SIE needs to be corrected to describe the charges and dipoles in the ion pair correctly. The use of range-separated functionals allows us to obtain interaction energies close to the CCSD(T) level. © 2017 Wiley Periodicals, Inc.

14.
Breast Cancer Res ; 18(1): 126, 2016 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-27955684

RESUMO

BACKGROUND: Pertuzumab, trastuzumab, and docetaxel is standard of care for first-line treatment of HER2-positive metastatic breast cancer (MBC). However, alternative chemotherapy partners are required to align with patient/physician preferences and to increase treatment flexibility. We report VELVET Cohort 1 results in which the efficacy and safety of pertuzumab and trastuzumab, administered sequentially in separate infusions, followed by vinorelbine, were evaluated. Cohort 2, where pertuzumab and trastuzumab were administered in a single infusion, followed by vinorelbine, recruited after Cohort 1 was fully enrolled, will be reported later. METHODS: In this multicenter, two-cohort, open-label, phase II study, patients with HER2-positive locally advanced or MBC who had not received chemotherapy or biological therapy for their advanced disease received 3-weekly pertuzumab (840 mg loading, 420 mg maintenance doses) and trastuzumab (8 mg/kg loading, 6 mg/kg maintenance doses), followed by vinorelbine (25 mg/m2 initial dose, 30-35 mg/m2 maintenance doses) on days 1 and 8 or 2 and 9 of each 3-weekly cycle. Study treatment was given until investigator-assessed disease progression or unacceptable toxicity. The primary endpoint was investigator-assessed objective response rate (ORR) in patients with measurable disease at baseline per RECIST v1.1. Secondary endpoints included progression-free survival (PFS) and safety. RESULTS: Cohort 1 enrolled 106 patients. Investigator-assessed ORR was 74.2% (95% CI 63.8-82.9) in intent-to-treat patients with measurable disease (89/106 [84.0%]). Median PFS was 14.3 months (95% CI 11.2-17.5) in the intent-to-treat population. Treatment was reasonably well tolerated, with no unexpected toxicities. Diarrhea (61/106 patients [57.5%]) and neutropenia (54/106 [50.9%]) were the most common adverse events (AEs); neutropenia (33/106 [31.1%]) and leukopenia (14/106 [13.2%]) were the most common grade ≥3 AEs. Serious AEs were reported in 32/106 (30.2%) patients. AEs led to study drug discontinuation in 36/106 patients (34.0%). Eighteen of 106 patients (17.0%) had AEs suggestive of congestive heart failure; however, there were no confirmed cases. CONCLUSIONS: The vinorelbine, pertuzumab, and trastuzumab combination is active and reasonably well tolerated. This regimen offers an alternative for patients who cannot receive docetaxel for first-line treatment of HER2-positive locally advanced or MBC. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01565083 , registered on 26 March 2012.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Receptor ErbB-2/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Biomarcadores Tumorais , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Retratamento , Análise de Sobrevida , Trastuzumab/administração & dosagem , Resultado do Tratamento , Vimblastina/administração & dosagem , Vimblastina/análogos & derivados , Vinorelbina
15.
Neurodegener Dis ; 16(5-6): 337-41, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27188850

RESUMO

BACKGROUND: In the last years different studies have reported an increase of amyotrophic lateral sclerosis (ALS) incidence, highlighting the role of the environment in this disease. This prompted us to review ALS cases diagnosed at our hospital in the last decade and to compare them with a previous ALS series reported in our region 30 years ago. METHODS: We reviewed those ALS cases diagnosed at our centre between 2004 and 2013. Subsequently, we compared them with the previous series regarding clinical and epidemiological features. RESULTS: A total of 53 patients (30 males, 23 females) were included. The annual incidence was 1.7 cases per 100,000 inhabitants (2.2 and 1.2 per 100,000 in males and females, respectively), which was significantly higher than in the previous series (1 case per 100,000 inhabitants). Otherwise, the clinical and epidemiological features were similar in both series. The median age at symptom onset was 67 years, with a median diagnosis delay of 6 months. About two thirds of the patients presented with systemic ALS, whereas the remaining had a bulbar onset. Weakness, dysphagia, and dysarthria were the most common clinical symptoms at diagnosis. The median survival from symptom onset was 22 months. CONCLUSION: After 3 decades, the annual incidence of ALS has almost doubled in our region. We did not find significant differences regarding other clinical or epidemiological features.


Assuntos
Esclerose Lateral Amiotrófica/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Esclerose Lateral Amiotrófica/diagnóstico , Feminino , Humanos , Incidência , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Saúde da População Rural , Espanha/epidemiologia , Saúde da População Urbana
16.
Artigo em Inglês | MEDLINE | ID: mdl-26886740

RESUMO

Research on similarity searching of cheminformatic data sets has been focused on similarity measures using fingerprints. However, nominal scales are the least informative of all metric scales, increasing the tied similarity scores, and decreasing the effectivity of the retrieval engines. Tanimoto's coefficient has been claimed to be the most prominent measure for this task. Nevertheless, this field is far from being exhausted since the computer science no free lunch theorem predicts that "no similarity measure has overall superiority over the population of data sets". We introduce 12 relational agreement (RA) coefficients for seven metric scales, which are integrated within a group fusion-based similarity searching algorithm. These similarity measures are compared to a reference panel of 21 proximity quantifiers over 17 benchmark data sets (MUV), by using informative descriptors, a feature selection stage, a suitable performance metric, and powerful comparison tests. In this stage, RA coefficients perform favourably with repect to the state-of-the-art proximity measures. Afterward, the RA-based method outperform another four nearest neighbor searching algorithms over the same data domains. In a third validation stage, RA measures are successfully applied to the virtual screening of the NCI data set. Finally, we discuss a possible molecular interpretation for these similarity variants.


Assuntos
Química/métodos , Bases de Dados de Compostos Químicos , Informática/métodos , Algoritmos , Mineração de Dados
17.
J Clin Oncol ; 33(32): 3788-95, 2015 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-26416999

RESUMO

PURPOSE: Capecitabine is an active drug in metastatic breast cancer (BC). GEICAM/2003-10 is an adjuvant trial to investigate the integration of capecitabine into a regimen of epirubicin and docetaxel for node-positive early BC. PATIENTS AND METHODS: Patients with operable node-positive BC (T1-3/N1-3) were eligible. After surgery, 1,384 patients were randomly assigned to receive epirubicin plus cyclophosphamide (EC; 90 and 600 mg/m(2), respectively, × four cycles), followed by docetaxel (100 mg/m(2) × four cycles; EC-T) or epirubicin plus docetaxel (ET; 90 and 75 mg/m(2), respectively, × four cycles), followed by capecitabine (1,250 mg/m(2) twice a day on days 1 to 14, × four cycles; ET-X); all regimens were given every 3 weeks. The primary end point was invasive disease-free survival. Secondary end points included safety (with an alopecia-specific study) and overall survival (OS). RESULTS: After a median follow-up of 6.6 years and 297 events, 86% of patients who received EC-T and 82% of those who received ET-X were invasive disease free at 5 years (hazard ratio, 1.30; 95% CI, 1.03 to 1.64; log-rank P = .03). The OS difference between arms was not statistically significant (hazard ratio, 1.13; 95% CI, 0.82 to 1.55; log-rank P = .46). The most frequent grade 3 to 4 adverse events in the EC-T versus ET-X arms were neutropenia (19% v 10%), with 7% febrile neutropenia across arms; fatigue (13% v 11%); diarrhea (3% v 11%); hand-foot syndrome (2% v 20%); mucositis (6% v 5%); vomiting (both, 5%); and myalgia (4.5% v 1%). Incomplete scalp hair recovery was more frequent in the EC-T than ET-X arm (30% v 14%), and patients who received EC-T wore wigs significantly longer than those who received ET-X (8.35 v 6.03 months). CONCLUSION: Invasive disease-free survival, but not OS, was significantly superior for patients with node-positive early BC who received the adjuvant standard schedule EC-T than for those who received the experimental ET-X regimen. Toxicity profiles differed substantially across arms.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linfonodos/patologia , Adulto , Idoso , Neoplasias da Mama/cirurgia , Capecitabina/administração & dosagem , Capecitabina/efeitos adversos , Quimioterapia Adjuvante , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Intervalo Livre de Doença , Docetaxel , Esquema de Medicação , Epirubicina/administração & dosagem , Epirubicina/efeitos adversos , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Seguimentos , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Razão de Chances , Taxoides/administração & dosagem , Taxoides/efeitos adversos , Resultado do Tratamento
18.
Acta Radiol ; 56(11): 1300-7, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25348477

RESUMO

BACKGROUND: Antiangiogenic drugs are being used in the treatment of locally advanced breast cancer. The effect of these drugs can be monitorized using high temporal resolution dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). PURPOSE: To evaluate changes in tumor microvasculature induced by bevacizumab and the usefulness of these changes predicting response to further neoadjuvant therapy. MATERIAL AND METHODS: Seventy patients with locally advanced breast cancers were treated with one cycle of bevacizumab followed by neoadjuvant therapy, combining bevacizumab and cytotoxic chemotherapy. Two DCE-MRI were performed before and after bevacizumab. Changes in tumoral volume, pharmacodynamic curves, and pharmacokinetic variables (K(trans), Kep, Ve, AUC90) in a ROI (ROI 1) encompassing the entire tumor and in another ROI (ROI 2) in the area of higher values of K(trans) were analyzed. Correlations with pathological response were made: parametrical and non-parametrical statistical analysis and ROC curves were used; a P < 0.05 was considered significant. RESULTS: Significant changes in tumoral volume (-4%), pharmacodynamic curves, and pharmacokinetic variables in ROI 1 K(trans) (-45%), Kep (-38%), Ve (-11%), and AUC90 (-44%) and ROI 2 K(trans) (-43%), Kep (-39%), Ve (-5%), and AUC90 (-45%) were observed after bevacizumab (P < 0.05). The effect of bevacizumab was not different between responders and non-responders (P > 0.05), and these changes could not predict response to further neoadjuvant therapy. CONCLUSION: Bevacizumab induces remarkable tumoral volume, pharmacodynamics, and pharmacokinetic changes. However, these changes could not be used as early predictors for response to further neoadjuvant therapy.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Bevacizumab/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Inibidores da Angiogênese/farmacocinética , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bevacizumab/farmacocinética , Neoplasias da Mama/patologia , Quimioterapia Adjuvante , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Pessoa de Meia-Idade , Terapia Neoadjuvante , Estadiamento de Neoplasias , Compostos Organometálicos , Prognóstico , Estudos Prospectivos , Resultado do Tratamento
19.
J Comput Chem ; 34(28): 2460-71, 2013 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-23983208

RESUMO

Spectral shifts of rhodopsin, which are related to variations of the electron distribution in 11-cis-retinal, are investigated here using the method of deformed atoms in molecules. We found that systems carrying the M207R and S186W mutations display large perturbations of the π-conjugated system with respect to wild-type rhodopsins. These changes agree with the predicted behavior of the bond length alternation (BLA) and the blue shifts of vertical excitation energies of these systems. The effect of the planarity of the central and Schiff-base regions of retinal chain on the electronic structure of the chromophore is also investigated. By establishing nonlinear polynomial relations between BLA, chain distortions, and vertical excitation energies, we are also able to provide a semiquantitative approach for the understanding of the mechanisms regulating spectral shifts in rhodopsin and its mutants.


Assuntos
Elétrons , Retinaldeído/química , Rodopsina/química , Animais , Bovinos , Humanos , Modelos Moleculares , Simulação de Dinâmica Molecular , Mutação , Rodopsina/genética , Eletricidade Estática
20.
J Steroid Biochem Mol Biol ; 138: 348-58, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23872659

RESUMO

Parallel ligand- and structure-based virtual screenings of 269 steroids with anabolic activity evaluated in vivo were performed. The quantitative structure-activity relationship (QSAR) model expressed by selected descriptors as the octanol-water partition coefficient, the molar volume and the quantum mechanical calculated charge values on atoms C1, C2, C5, C9, C10, C14 and C17 of the steroid skeleton, expresses structural features of anabolic steroids (AS) contributing to the transport and steroid-receptor interaction. On the other hand, computational simulations of a candidate ligand binding to a receptor study (a "docking" procedure) predict the association of these AS with the human androgen receptor (AR). Fourteen compounds were identified as lead; the most potent was the 7α-methylestr-4-en-3, 17-dione. It was concluded that a good anabolic activity requires hydrogen bonding interactions between both Arg752 and Gln711 residues in the cycles A with O3 atom of the steroid and either Asn705 and Thr877 residues in the cycles D of steroid with O17 atom.


Assuntos
Anabolizantes/química , Anabolizantes/metabolismo , Relação Quantitativa Estrutura-Atividade , Esteroides/química , Esteroides/metabolismo , Análise por Conglomerados , Humanos , Receptores Androgênicos/química , Receptores Androgênicos/metabolismo
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