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1.
Clin Chem Lab Med ; 59(7): 1221-1229, 2021 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-33691348

RESUMO

OBJECTIVES: Epidermal growth factor receptor (EGFR) biomarker testing using blood-based liquid biopsies remains challenging due to the low concentration of circulating tumor DNA (ctDNA) in certain plasma samples. The aim of this study is to evaluate the usefulness for EGFR biomarker testing of ctDNA from pleural effusions, cerebrospinal fluids, ascites and pericardial effusions obtained during the clinical management of lung adenocarcinoma patients. METHODS: For comparison purposes, 23 paired plasma and body fluid samples were collected from 17 patients with EGFR-positive lung adenocarcinoma. After circulating free DNA (cfDNA) isolation, samples were evaluated for the initial EGFR-sensitizing mutation and the p.T790M resistance mutation by array-based digital PCR (dPCR). RESULTS: Body fluids had more cfDNA than plasma samples (1.90 vs. 0.36 ng/µL; p=0.0130), and more samples tested positive for EGFR mutations (21 vs. 16 samples), with a total of 28 vs. 22 variants detected. Furthermore, mutant allele frequencies (MAFs) observed in body fluids were significantly higher than those assessed in the paired plasma samples for EGFR-sensitizing mutations (median MAFs = 15.8 vs. 0.8%; p=0.0004) as well as for the p.T790M resistance mutation (median MAFs = 8.69 vs. 0.16%; p=0.0390). Importantly, two patients who had progressed on first-generation EGFR-tyrosine kinase inhibitors with a dubious result for p.T790M plasma (MAFs = 0.11%) had an indisputably positive result in their respective body fluid samples (MAFs = 10.25 and 9.66%). CONCLUSIONS: ctDNA derived from body fluids is an informative source for EGFR biomarker testing, with greater sensitivity than plasma samples.


Assuntos
Adenocarcinoma de Pulmão , Líquidos Corporais , Carcinoma Pulmonar de Células não Pequenas , DNA Tumoral Circulante , Neoplasias Pulmonares , Adenocarcinoma de Pulmão/diagnóstico , Adenocarcinoma de Pulmão/genética , Biomarcadores , DNA Tumoral Circulante/genética , Receptores ErbB/genética , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Mutação , Inibidores de Proteínas Quinases
2.
J Am Chem Soc ; 142(37): 16051-16063, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32822170

RESUMO

The dynamic adaptability of tetragonal prismatic nanocapsule 18+ in the selective separation of fullerenes and endohedral metallofullerenes (EMFs) remains unexplored. Therefore, the essential molecular details of the fullerene recognition and binding process into the coordination capsule and the origins of fullerene selectivity remain elusive. In this work, the key steps of fullerene recognition and binding processes have been deciphered by designing a protocol which combines 1H-1H exchange spectroscopy (2D-EXSY) NMR experiments, long time-scale Molecular Dynamics (MD) and accelerated Molecular Dynamics (aMD) simulations, which are combined to completely reconstruct the spontaneous binding and unbinding pathways from nanosecond to second time-range. On one hand, binding (k'on) and unbinding (koff) rate constants were extracted from 1H-1H exchange spectroscopy (EXSY) NMR experiments for both C60 and C70. On the other hand, MD and aMD allowed monitoring the molecular basis of the encapsulation and guest competition processes at a very early stage under nonequilibrium conditions. The receptor capsule displays dynamical adaptability features similar to those observed in the process of biomolecular recognition in proteins. In addition, the encapsulation of bis-aza[60]fullerene (C59N)2 within a supramolecular coordination capsule has been studied for the first time, showcasing the pros and cons of the dumbbell-shaped guest in the dynamics of the encapsulation process and in the stability of the final bound adduct. The powerful combination of NMR, MD, and aMD methodologies allows to obtain a precise picture of the subtle events directing the encapsulation and is thus a predictive tool for understanding host-guest encapsulation and interactions in numerous supramolecular systems.

3.
Clin Anat ; 33(4): 488-499, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31050830

RESUMO

Combined ultrasound (US)-guided blockade of the suprascapular and axillary nerves (ANs) has been proposed as an alternative to interscalene blockade for pain control in shoulder joint pathology or postsurgical care. This technique could help avoid respiratory complications and/or almost total upper limb palsy. Nowadays, the AN blockade is mostly performed using an in-plane caudal-to-cephalic approach from the posterior surface of the shoulder, reaching the nerve immediately after it exits the neurovascular quadrangular space (part of the spatium axillare). Despite precluding most respiratory complications, this approach has not made postsurgical pain relief any better than an interscalene blockade, probably because articular branches of the AN are not blocked.Cephalic-to-caudal methylene blue injections were placed in the first segment of the AN of six Thiel-embalmed cadavers using an US-guided anterior approach in order to compare the distribution with that produced by a posterior approach to the contralateral AN in the same cadaver. Another 21 formalin-fixed cadavers were bilaterally dissected to identify the articular branches of the AN.We found a good spread of the dye on the AN and a constant relationship of this nerve with the subscapularis muscle. The dye reached the musculocutaneous nerve, which also contributes to shoulder joint innervation. We describe the anatomical landmarks for an ultrasonography-guided anterior AN blockade and hypothesize that this anterior approach will provide better pain control than the posterior approach owing to complete blocking of the joint nerve. Clin. Anat. 33:488-499, 2020. © 2019 Wiley Periodicals, Inc.


Assuntos
Bloqueio do Plexo Braquial/métodos , Plexo Braquial/anatomia & histologia , Articulação do Ombro/inervação , Articulação do Ombro/cirurgia , Ultrassonografia de Intervenção , Idoso , Idoso de 80 Anos ou mais , Cadáver , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
4.
Soft Matter ; 15(4): 537-545, 2019 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-30516225

RESUMO

We study the competition for space between two cell lines that differ only in the expression of the Ras oncogene. The two cell populations are initially separated and set to migrate antagonistically towards an in-between stripe of free substrate. After contact, their interface moves towards the population of normal cells. We interpret the velocity and traction force data taken before and after contact thanks to a hydrodynamic description of collectively migrating cohesive cell sheets. The kinematics of cells, before and after contact, allows us to estimate the relative material parameters for both cell lines. As predicted by the model, the transformed cell population with larger collective stresses pushes the wild type cell population.


Assuntos
Transformação Celular Neoplásica , Estresse Mecânico , Proteínas ras/metabolismo , Fenômenos Biomecânicos , Movimento Celular , Células HEK293 , Humanos
5.
Inorg Chem ; 57(7): 3529-3539, 2018 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-29293325

RESUMO

The encapsulation of coordination complexes in a tetragonal prismatic nanocage (1·(BArF)8) built from Zn-porphyrin and macrocyclic Pd-clip-based synthons is described. The functional duality of the guest ligand L1 allows for its encapsulation inside the cage 1·(BArF)8, along with the simultaneous coordination of ZnII, CuII, or FeIII metal ions. Remarkably, the coordination chemistry inside the host-guest adduct L1⊂1·(BArF)8 occurs in both solution solution and solid state. The resulting confined metallocomplexes have been characterized by means of UV-vis, ESI-HRMS, NMR, and EPR techniques. Furthermore, the emission of the Zn-porphyrin fluorophores of 1·(BArF)8 is strongly quenched by the encapsulation of paramagnetic complexes, representing a remarkable example of guest-dependent tuning of the host fluorescence.

6.
Int J Med Sci ; 15(1): 10-15, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29333082

RESUMO

BACKGROUND: The production of anti-drug antibodies (ADAs) against IgG monoclonal antibodies (mAbs) targeting tumour necrosis factor (TNF) is an important cause of loss of response to anti-TNF mAbs in patients with inflammatory bowel diseases (IBD) such as Crohn's disease (CD) and ulcerative colitis (UC). Since receptors for the Fc portion of IgG (FCGRs) are involved in the degradation of IgG complexes, we hypothesised that a polymorphism in FCGR3A (V158F; rs396991) gene could be involved in anti-TNF ADA generation and treatment resistance. MATERIAL AND METHODS: A cohort of 103 IBD patients (80 CD, 23 UC) were genotyped and serum level of both anti-TNFs (infliximab or adalimumab) and ADA against them were measured. RESULTS: No significant differences were observed between ADA occurrence or V158F genotype and type of disease or the kind of anti-TNF administrated. Interestingly, VV genotype correlated with patients producing ADA (VV: 37.5% vs. FV: 10.6% or FF: 5%; p=0.004) and was an independent predictor of this event after multivariate analysis. Moreover, VV genotype also correlated with those patients receiving anti-TNF dose intensification (p=0.03). CONCLUSION: FCGR3A V158F polymorphism seems to be associated with ADA production against mAbs and it could be taken into account when considering the dose and type of anti-TNF in IBD patients.


Assuntos
Anticorpos Anti-Idiotípicos/imunologia , Colite Ulcerativa/tratamento farmacológico , Doença de Crohn/tratamento farmacológico , Fármacos Gastrointestinais/imunologia , Receptores de IgG/genética , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Adalimumab/sangue , Adalimumab/imunologia , Adalimumab/uso terapêutico , Adulto , Anticorpos Anti-Idiotípicos/sangue , Estudos de Coortes , Colite Ulcerativa/sangue , Colite Ulcerativa/genética , Colite Ulcerativa/imunologia , Doença de Crohn/sangue , Doença de Crohn/genética , Doença de Crohn/imunologia , Feminino , Fármacos Gastrointestinais/uso terapêutico , Humanos , Infliximab/sangue , Infliximab/imunologia , Infliximab/uso terapêutico , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Receptores de IgG/imunologia
7.
Proc Natl Acad Sci U S A ; 112(50): 15314-9, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26627719

RESUMO

Although collective cell motion plays an important role, for example during wound healing, embryogenesis, or cancer progression, the fundamental rules governing this motion are still not well understood, in particular at high cell density. We study here the motion of human bronchial epithelial cells within a monolayer, over long times. We observe that, as the monolayer ages, the cells slow down monotonously, while the velocity correlation length first increases as the cells slow down but eventually decreases at the slowest motions. By comparing experiments, analytic model, and detailed particle-based simulations, we shed light on this biological amorphous solidification process, demonstrating that the observed dynamics can be explained as a consequence of the combined maturation and strengthening of cell-cell and cell-substrate adhesions. Surprisingly, the increase of cell surface density due to proliferation is only secondary in this process. This analysis is confirmed with two other cell types. The very general relations between the mean cell velocity and velocity correlation lengths, which apply for aggregates of self-propelled particles, as well as motile cells, can possibly be used to discriminate between various parameter changes in vivo, from noninvasive microscopy data.


Assuntos
Fenômenos Biofísicos , Movimento Celular , Células/citologia , Animais , Brônquios/citologia , Moléculas de Adesão Celular/metabolismo , Análise por Conglomerados , Simulação por Computador , Cães , Células Epiteliais/citologia , Fricção , Humanos , Células Madin Darby de Rim Canino , Camundongos , Modelos Teóricos , Células NIH 3T3 , Fatores de Tempo
8.
Angew Chem Int Ed Engl ; 57(35): 11294-11299, 2018 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-29917307

RESUMO

Supramolecular nanocapsule 1⋅(BArF)8 is able to sequentially and selectively entrap recently discovered U2 @C80 and unprecedented Sc2 CU@C80 , simply by soaking crystals of 1⋅(BArF)8 in a toluene solution of arc-produced soot. These species, selectively and stepwise absorbed by 1⋅(BArF)8 , are easily released, obtaining highly pure fractions of U2 @C80 and Sc2 CU@C80 in one step. Sc2 CU@C80 represents the first example of a mixed metal actinide-based endohedral metallofullerene (EMF). Remarkably, the host-guest studies revealed that 1⋅(BArF)8 is able to discriminate EMFs with the same carbon cage but with different encapsulated cluster and computational studies provide support for these observations.

9.
Chemistry ; 23(15): 3553-3557, 2017 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-28135408

RESUMO

A self-assembled CuII -based nanocapsule enables efficient and straightforward isolation of Sc3 N@C80 from arc-processed raw soot. The newly designed CuII -based supramolecular nanocapsule 5⋅(OTf)8 was used to effectively entrap fullerenes and endohedral metallofullerenes (EMFs) with different affinities depending on their size and shape. Moreover, we took advantage of the sharply different entrapment abilities of the 5⋅(OTf)8 cage in the solid state versus in solution to encapsulate all the species with the exception of Sc3 N@C80 (both Ih and D5h isomers), which remains pure in solution. HPLC quantification determined that up to 85 % of the total Sc3 N@C80 content in the initial mixture was recovered in very high purity (>99.5 %). The complete release of the encapsulated species with an orthogonal solvent-washing strategy regenerates 5⋅(OTf)8 ready to be re-used. This approach opens new opportunities for EMFs purification.

10.
Ann Pharmacother ; 51(5): 388-393, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27920336

RESUMO

BACKGROUND: The introduction of anti-tumor necrosis factor α (anti-TNFα) drugs has improved the clinical outcomes in rheumatoid arthritis (RA) and ankylosing spondylitis (AS). However, these drugs may cause adverse effects that motivate a change in or discontinuation of the treatment. OBJECTIVE: To evaluate the causes of discontinuation or changes in the dosage regimen in a cohort of patients with RA and AS treated with infliximab, adalimumab, etanercept, and golimumab under clinical practice conditions. METHODS: This was a retrospective observational study that included patients with RA or AS treated with anti-TNFα drugs between 2008 and 2013. Changes in the dosage regimen, reasons for treatment discontinuation, and adverse effects were recorded and analyzed. Time to discontinuation was estimated using Kaplan-Meier survival analysis. RESULTS: A total of 123 patients with RA and 93 patients with AS were treated with anti-TNFα therapy. During the study, 55.3% of RA patients and 41.7% of AS patients had stopped the treatment. The most frequent changes were modifications in the dosing, and the most frequent adverse effects were reactions after the infusion or injection (53.8% and 66.7% in RA and AS, respectively). Drug survival of etanercept in RA (67.9%) is greater than for adalimumab and infliximab, whereas drug survival of infliximab in AS (70.0%) is greater than for etanercept and adalimumab at 5 years, although there were no significant differences ( P = 0.098 in RA and 0.194 in AS). CONCLUSIONS: The main cause of discontinuation of anti-TNFα is therapeutic failure in both diseases. Etanercept and infliximab have the best survival rates in RA and AS, respectively.


Assuntos
Antirreumáticos/efeitos adversos , Artrite Reumatoide/tratamento farmacológico , Uso de Medicamentos/tendências , Espondilite Anquilosante/tratamento farmacológico , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Adalimumab/administração & dosagem , Adalimumab/efeitos adversos , Adalimumab/uso terapêutico , Adulto , Idoso , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/uso terapêutico , Antirreumáticos/administração & dosagem , Antirreumáticos/uso terapêutico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etiologia , Etanercepte/administração & dosagem , Etanercepte/efeitos adversos , Etanercepte/uso terapêutico , Feminino , Humanos , Infliximab/administração & dosagem , Infliximab/efeitos adversos , Infliximab/uso terapêutico , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Receptores do Fator de Necrose Tumoral/uso terapêutico , Estudos Retrospectivos , Falha de Tratamento
11.
Proc Natl Acad Sci U S A ; 111(22): 8055-60, 2014 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-24835175

RESUMO

Like liquid droplets, cellular aggregates, also called "living droplets," spread onto adhesive surfaces. When deposited onto fibronectin-coated glass or polyacrylamide gels, they adhere and spread by protruding a cellular monolayer (precursor film) that expands around the droplet. The dynamics of spreading results from a balance between the pulling forces exerted by the highly motile cells at the periphery of the film, and friction forces associated with two types of cellular flows: (i) permeation, corresponding to the entry of the cells from the aggregates into the film; and (ii) slippage as the film expands. We characterize these flow fields within a spreading aggregate by using fluorescent tracking of individual cells and particle imaging velocimetry of cell populations. We find that permeation is limited to a narrow ring of width ξ (approximately a few cells) at the edge of the aggregate and regulates the dynamics of spreading. Furthermore, we find that the subsequent spreading of the monolayer depends heavily on the substrate rigidity. On rigid substrates, the migration of the cells in the monolayer is similar to the flow of a viscous liquid. By contrast, as the substrate gets softer, the film under tension becomes unstable with nucleation and growth of holes, flows are irregular, and cohesion decreases. Our results demonstrate that the mechanical properties of the environment influence the balance of forces that modulate collective cell migration, and therefore have important implications for the spreading behavior of tissues in both early development and cancer.


Assuntos
Adesão Celular/fisiologia , Comunicação Celular/fisiologia , Movimento Celular/fisiologia , Modelos Biológicos , Sarcoma/patologia , Resinas Acrílicas , Adesivos , Animais , Caderinas/metabolismo , Linhagem Celular Tumoral , Progressão da Doença , Fricção , Proteínas de Fluorescência Verde/metabolismo , Lipídeo A/análogos & derivados , Proteínas Luminescentes/metabolismo , Mecanotransdução Celular/fisiologia , Camundongos , Microscopia Confocal/métodos , Sarcoma/metabolismo , Agentes Molhantes , Proteína Vermelha Fluorescente
12.
Chem Soc Rev ; 45(1): 40-62, 2016 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-26456881

RESUMO

Fullerene extracts are easily available from fullerene soot, but finding an efficient strategy to obtain them in pure form remains elusive, especially for higher fullerenes (Cx, x > 70). The properties of the latter remain unclear and their potential application to multiple research fields has not been developed mainly due to their purification difficulties. In this Tutorial Review we cover the use of molecular receptors for the separation of fullerenes by means of host-guest interactions. This strategy allows gaining selectivity, no specialized equipment is required and, ideally, recyclable systems can be designed. We focus on the metallosupramolecular receptors using the metal-ligand coordination approach, which offers a controlled and versatile strategy to design fullerene hosts, and the latest strategies to release the fullerene guest will be described. The field is probably in its beginnings but it is rapidly evolving and we are confident that this tutorial review will help researchers to rapidly gain a general overview of the main works and concepts that are leading this promising strategy and that may lead towards a useful methodology to purify fullerenes.


Assuntos
Fulerenos/química , Compostos Organometálicos/química , Sítios de Ligação , Cristalografia por Raios X , Fulerenos/isolamento & purificação , Ligantes , Substâncias Macromoleculares/química , Modelos Moleculares , Estrutura Molecular
13.
J Am Chem Soc ; 137(7): 2680-7, 2015 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-25632976

RESUMO

Regio- and enantioselective hydroformylation of styrenes is attained upon embedding a chiral Rh complex in a nonchiral supramolecular cage formed from coordination-driven self-assembly of macrocyclic dipalladium complexes and tetracarboxylate zinc porphyrins. The resulting supramolecular catalyst converts styrene derivatives into aldehyde products with much higher chiral induction in comparison to the nonencapsulated Rh catalyst. Spectroscopic analysis shows that encapsulation does not change the electronic properties of the catalyst nor its first coordination sphere. Instead, enhanced enantioselectivity is rationalized by the modification of the second coordination sphere occurring upon catalyst inclusion inside the cage, being one of the few examples in achieving an enantioselective outcome via indirect through-space control of the chirality around the catalyst center. This effect resembles those taking place in enzymatic sites, where structural constraints imposed by the enzyme cavity can impart stereoselectivities that cannot be attained in bulk. These results are a showcase for the future development of asymmetric catalysis by using size-tunable supramolecular capsules.


Assuntos
Aldeídos/química , Ródio/química , Estireno/química , Amidas/química , Catálise , Modelos Moleculares , Conformação Molecular , Ácidos Fosfóricos/química , Estereoisomerismo
14.
Ultrasound Obstet Gynecol ; 46(6): 713-7, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25670681

RESUMO

OBJECTIVE: To estimate the combined value of fetal cerebral Doppler examination and Bishop score for predicting perinatal outcome after labor induction for small-for-gestational-age (SGA) fetuses in the presence of normal umbilical artery Doppler recordings. METHODS: We conducted a cohort study in two tertiary centers, including 164 women with normal umbilical artery Doppler recordings who underwent induction of labor because of an estimated fetal weight < 10(th) percentile. The fetal middle cerebral artery pulsatility index and cerebroplacental ratio (CPR) were obtained in all cases within 24 h before induction. Cervical condition was assessed at admission using the Bishop score. A predictive model for perinatal outcomes was constructed using a decision-tree analysis algorithm. RESULTS: Both a very unfavorable cervix, defined as a Bishop score < 2, (odds ratio (OR), 3.18; 95% CI, 1.28-7.86) and an abnormal CPR (OR, 2.54; 95% CI, 1.18-5.61) were associated with an increased likelihood of emergency Cesarean section for fetal distress, but only the latter was significantly associated with the need for neonatal admission (OR, 2.43; 95% CI, 1.28-4.59). In the decision-tree analysis, both criteria significantly predicted the likelihood of Cesarean section for fetal distress. CONCLUSION: Combined use of the Bishop score and CPR improves the ability to predict overall Cesarean section (for any indication), emergency Cesarean section for fetal distress, and neonatal admission after labor induction for late-onset SGA in the presence of normal umbilical artery Doppler recordings.


Assuntos
Artérias Cerebrais/embriologia , Colo do Útero/patologia , Peso Fetal , Trabalho de Parto Induzido/efeitos adversos , Resultado da Gravidez , Adulto , Artérias Cerebrais/diagnóstico por imagem , Cesárea/estatística & dados numéricos , Feminino , Sofrimento Fetal/etiologia , Sofrimento Fetal/cirurgia , Feto/irrigação sanguínea , Idade Gestacional , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Unidades de Terapia Intensiva Neonatal/estatística & dados numéricos , Razão de Chances , Placenta/irrigação sanguínea , Placenta/diagnóstico por imagem , Gravidez , Ultrassonografia Doppler/métodos , Ultrassonografia Pré-Natal/métodos , Artérias Umbilicais/diagnóstico por imagem , Doenças do Colo do Útero/complicações , Doenças do Colo do Útero/patologia
15.
J Obstet Gynaecol Res ; 41(3): 377-82, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25303725

RESUMO

AIM: To evaluate the reliability of two techniques of cervical ripeness assessment at the beginning of labor induction, as assessed by inexperienced observers. METHODS: A total of 120 women were prospectively studied at admission for labor induction. Two independent physicians examined consenting women successively but separately. One experienced consultant and one of the six first-year obstetrics residents composed the pairs of observers. The trainees had very limited prior experience with cervical ultrasound scan or evaluating Bishop score. Cervical length and Bishop score were evaluated according to standard methodology. Reliability was described by intraclass correlation coefficients (ICC) and coefficients of variation (COV). Ultrasound cervical length was plotted according to the Bland-Altman method. RESULTS: The median Bishop score and mean cervical length were similar for all observers. Ultrasound cervical length and Bishop score were highly reliable when evaluated by first-year residents. Ultrasound cervical length showed the highest interobserver agreement, with ICC values over 0.9 and COV values of approximately 10% or less for all trainees. The Bishop score was also reliable, but with lower ICC and higher COV values. CONCLUSION: Bishop score and ultrasound cervical length examination for the management of labor induction are accurate and easy to learn by inexperienced first-year residents. However, cervical length showed higher reliability than the Bishop score.


Assuntos
Maturidade Cervical , Colo do Útero/diagnóstico por imagem , Exame Ginecológico , Adulto , Competência Clínica , Feminino , Humanos , Internato e Residência , Trabalho de Parto Induzido , Variações Dependentes do Observador , Gravidez , Estudos Prospectivos , Reprodutibilidade dos Testes
16.
EMBO J ; 29(14): 2461-71, 2010 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-20543817

RESUMO

The extracellular domains of neuroligins and neurexins interact through Ca(2+) to form flexible trans-synaptic associations characterized by selectivity for neuroligin or neurexin subtypes. This heterophilic interaction, essential for synaptic maturation and differentiation, is regulated by gene selection, alternative mRNA splicing and post-translational modifications. A new, 2.6 A-resolution crystal structure of a soluble neurexin-1beta-neuroligin-4 (Nrx1beta-NL4) complex permits a detailed description of the Ca(2+)-coordinated interface and unveils concerted positional rearrangements of several residues of NL4, not observed in neuroligin-1, associated with Nrx1beta binding. Surface plasmon resonance analysis of the binding of structure-guided Nrx1beta mutants towards NL4 and neuroligin-1 shows that flexibility of the Nrx1beta-binding site in NL4 is reflected in a greater dissociation constant of the complex and higher sensitivity to ionic strength and pH variations. Analysis of neuroligin mutants points to critical functions for two respective residues in neuroligin-1 and neuroligin-2 in governing the affinity of the complexes. Although neuroligin-1 and neuroligin-2 have pre-determined conformations that respectively promote and prevent Nrx1beta association, unique conformational reshaping of the NL4 surface is required to permit Nrx1beta association.


Assuntos
Proteínas de Transporte/química , Proteínas de Membrana/química , Proteínas do Tecido Nervoso/química , Estrutura Terciária de Proteína , Sinapses/metabolismo , Processamento Alternativo , Sequência de Aminoácidos , Sítios de Ligação , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Moléculas de Adesão Celular Neuronais , Cristalografia por Raios X , Humanos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Ligação Proteica , Processamento de Proteína Pós-Traducional , Alinhamento de Sequência , Ressonância de Plasmônio de Superfície , Sinapses/ultraestrutura
17.
Mol Genet Genomic Med ; 12(1): e2348, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38146137

RESUMO

BACKGROUND: Juvenile Polyposis Syndrome (JPS) is a rare autosomal dominant hereditary disorder characterized by the development of multiple hamartomatous gastrointestinal polyps. Here, we present a case of JPS with a mosaic variant in SMAD4. METHODS: Exome sequencing TRIO analysis, using germline DNA from the biological mother and father along with the index case (IC). RESULTS: A 46-year-old male with no family history of cancer presented with chronic iron deficiency anemia and was diagnosed with massive gastric polyposis (≥100 polyps). At the age of 59, he underwent a total gastrectomy, revealing numerous polyps occupying the entire gastric mucosa, including a 5 cm gastric hyperplastic polyp with high-grade dysplasia and focal adenocarcinoma. TRIO analysis identified the c.386A>C p.(Asn129Thr) variant in the SMAD4 gene at an allele frequency (AF) of 22%, suggesting its mosaic origin. Subsequently, the variant was found in heterozygosity in the IC's son, who exhibited two subcentimeter polyps in the colon and seven inflammatory gastric polyps with gastric inflammatory areas and hyperplasia, suggesting that the c.386A>C p.(Asn129Thr) variant in SMAD4 segregated with the phenotype. CONCLUSION: Our study provides evidence supporting the classification of the c.386A>C p.(Asn129Thr) variant in SMAD4 as a likely pathogenic variant. This finding contributes to improved accuracy in the diagnosis and genetic counseling of JPS.


Assuntos
Pólipos Adenomatosos , Polipose Intestinal/congênito , Síndromes Neoplásicas Hereditárias , Neoplasias Gástricas , Masculino , Humanos , Pessoa de Meia-Idade , Neoplasias Gástricas/genética , Síndromes Neoplásicas Hereditárias/genética , Síndromes Neoplásicas Hereditárias/patologia , Proteína Smad4/genética
18.
J Lipid Res ; 54(5): 1207-20, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23423838

RESUMO

Acid ceramidase (AC) catalyzes the hydrolysis of ceramide into sphingosine, in turn a substrate of sphingosine kinases that catalyze its conversion into the mitogenic sphingosine-1-phosphate. AC is expressed at high levels in several tumor types and has been proposed as a cancer therapeutic target. Using a model derived from PC-3 prostate cancer cells, the highly tumorigenic, metastatic, and chemoresistant clone PC-3/Mc expressed higher levels of the AC ASAH1 than the nonmetastatic clone PC-3/S. Stable knockdown of ASAH1 in PC-3/Mc cells caused an accumulation of ceramides, inhibition of clonogenic potential, increased requirement for growth factors, and inhibition of tumorigenesis and lung metastases. We developed de novo ASAH1 inhibitors, which also caused a dose-dependent accumulation of ceramides in PC-3/Mc cells and inhibited their growth and clonogenicity. Finally, immunohistochemical analysis of primary prostate cancer samples showed that higher levels of ASAH1 were associated with more advanced stages of this neoplasia. These observations confirm ASAH1 as a therapeutic target in advanced and chemoresistant forms of prostate cancer and suggest that our new potent and specific AC inhibitors could act by counteracting critical growth properties of these highly aggressive tumor cells.


Assuntos
Ceramidase Ácida/antagonistas & inibidores , Ceramidase Ácida/genética , Terapia de Alvo Molecular , Neoplasias da Próstata/genética , Ceramidase Ácida/metabolismo , Apoptose/genética , Linhagem Celular Tumoral , Ceramidas/metabolismo , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Lisofosfolipídeos/metabolismo , Masculino , Metástase Neoplásica , Neoplasias da Próstata/patologia , Neoplasias da Próstata/terapia , Esfingosina/análogos & derivados , Esfingosina/metabolismo
19.
Chemistry ; 19(4): 1445-56, 2013 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-23212936

RESUMO

The metal-directed supramolecular synthetic approach has paved the way for the development of functional nanosized molecules. In this work, we report the preparation of the new nanocapsule 3·(CF(3)SO(3))(8) with a A(4 B(2) tetragonal prismatic geometry, where A corresponds to the dipalladium hexaazamacrocyclic complex Pd-1, and B corresponds to the tetraanionic form of palladium 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin (2). The large void space of the inner cavity and the supramolecular affinity for guest molecules towards porphyrin-based hosts converts this nanoscale molecular 3D structure into a good candidate for host-guest chemistry. The interaction between this nanocage and different guest molecules has been studied by means of NMR, UV/Vis, ESI-MS, and DOSY experiments, from which highly selective molecular recognition has been found for anionic, planar-shaped π guests with association constants (K(a)) higher than 10(9) M(-1) , in front of non-interacting aromatic neutral or cationic substrates. DFT theoretical calculations provided insights to further understand this strong interaction. Nanocage 3·(CF(3)SO(3))(8) can not only strongly host one single molecule of M(dithiolene)(2) complexes (M=Au, Pt, Pd, and Ni), but also can finely tune their optical and redox properties. The very simple synthesis of both the supramolecular cage and the building blocks represents a step forward for the development of polyfunctional supramolecular nanovessels, which offer multiple applications as sensors or nanoreactors.

20.
Cell Mol Life Sci ; 69(10): 1689-703, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22205212

RESUMO

Newly generated olfactory receptor axons grow from the peripheral to the central nervous system aided by olfactory ensheathing cells (OECs). Thus, OEC transplantation has emerged as a promising therapy for spinal cord injuries and for other neural diseases. However, these cells do not present a uniform population, but instead a functionally heterogeneous population that exhibits a variety of responses including adhesion, repulsion, and crossover during cell-cell and cell-matrix interactions. Some studies report that the migratory properties of OECs are compromised by inhibitory molecules and potentiated by chemical gradients. Here, we demonstrated that rodent OECs express all the components of the Nogo receptor complex and that their migration is blocked by myelin. Next, we used cell tracking and traction force microscopy to analyze OEC migration and its mechanical properties over myelin. Our data relate the decrease of traction force of OEC with lower migratory capacity over myelin, which correlates with changes in the F-actin cytoskeleton and focal adhesion distribution. Lastly, OEC traction force and migratory capacity is enhanced after cell incubation with the Nogo receptor inhibitor NEP1-40.


Assuntos
Movimento Celular , Proteínas da Mielina/fisiologia , Bulbo Olfatório/citologia , Animais , Rastreamento de Células , Proteínas Ligadas por GPI/fisiologia , Camundongos , Proteínas da Mielina/metabolismo , Bainha de Mielina/metabolismo , Receptor Nogo 1 , Bulbo Olfatório/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Superfície Celular/fisiologia
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