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1.
Nature ; 609(7925): 41-45, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36045235

RESUMO

When protons and neutrons (nucleons) are bound into atomic nuclei, they are close enough to feel significant attraction, or repulsion, from the strong, short-distance part of the nucleon-nucleon interaction. These strong interactions lead to hard collisions between nucleons, generating pairs of highly energetic nucleons referred to as short-range correlations (SRCs). SRCs are an important but relatively poorly understood part of nuclear structure1-3, and mapping out the strength and the isospin structure (neutron-proton (np) versus proton-proton (pp) pairs) of these virtual excitations is thus critical input for modelling a range of nuclear, particle and astrophysics measurements3-5. Two-nucleon knockout or 'triple coincidence' reactions have been used to measure the relative contribution of np-SRCs and pp-SRCs by knocking out a proton from the SRC and detecting its partner nucleon (proton or neutron). These measurements6-8 have shown that SRCs are almost exclusively np pairs, but they had limited statistics and required large model-dependent final-state interaction corrections. Here we report on measurements using inclusive scattering from the mirror nuclei hydrogen-3 and helium-3 to extract the np/pp ratio of SRCs in systems with a mass number of three. We obtain a measure of the np/pp SRC ratio that is an order of magnitude more precise than previous experiments, and find a marked deviation from the near-total np dominance observed in heavy nuclei. This result implies an unexpected structure in the high-momentum wavefunction for hydrogen-3 and helium-3. Understanding these results will improve our understanding of the short-range part of the nucleon-nucleon interaction.

2.
Phys Rev Lett ; 132(16): 162501, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38701469

RESUMO

The electromagnetic form factors of the proton and neutron encode information on the spatial structure of their charge and magnetization distributions. While measurements of the proton are relatively straightforward, the lack of a free neutron target makes measurements of the neutron's electromagnetic structure more challenging and more sensitive to experimental or model-dependent uncertainties. Various experiments have attempted to extract the neutron form factors from scattering from the neutron in deuterium, with different techniques providing different, and sometimes large, systematic uncertainties. We present results from a novel measurement of the neutron magnetic form factor using quasielastic scattering from the mirror nuclei ^{3}H and ^{3}He, where the nuclear effects are larger than for deuterium but expected to largely cancel in the cross-section ratios. We extracted values of the neutron magnetic form factor for low-to-modest momentum transfer, 0.6

3.
Phys Rev Lett ; 128(13): 132003, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35426713

RESUMO

The ratio of the nucleon F_{2} structure functions, F_{2}^{n}/F_{2}^{p}, is determined by the MARATHON experiment from measurements of deep inelastic scattering of electrons from ^{3}H and ^{3}He nuclei. The experiment was performed in the Hall A Facility of Jefferson Lab using two high-resolution spectrometers for electron detection, and a cryogenic target system which included a low-activity tritium cell. The data analysis used a novel technique exploiting the mirror symmetry of the two nuclei, which essentially eliminates many theoretical uncertainties in the extraction of the ratio. The results, which cover the Bjorken scaling variable range 0.19

4.
Environ Manage ; 69(4): 768-780, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34028596

RESUMO

In the last years, the interest in ecosystem services (ESs) as a decision-making tool for environmental policy has been growing. The ES paradigm has also impacted the judicial system and in some countries the common law tradition. Experiences and lessons learned from the ES litigation have been already documented. In the initial analysis, this article aims to identify key trends in ESs case law in Latin America-a leading region in environmental constitutionalism-by exploring the judicial decisions issued by high courts and subnational environmental courts that mention or incorporate the ES term. In the second level of analysis, we focused on the Colombian Constitutional Court landmark decision; the Arroyo Bruno judgment aimed to protect the rights to water, food security, and health of the Wayuú indigenous people. We argue this is a groundbreaking ruling in Latin America, given that for the first time, a Court uses the ES-based approach to protect the environmental rights of ethnic communities, incorporating ES concepts to the constitutional law sphere and integrating into the same conversation, interdisciplinary and intercultural knowledge.


Assuntos
Direitos Humanos , Povos Indígenas , Colômbia , Ecossistema , Humanos , América Latina
5.
Actas Dermosifiliogr ; 113(1): 74-77, 2022 Jan.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-35244543

RESUMO

Although zoophilic dermatophytes remain the predominant cause of tinea capitis in Spain, an increase due to anthropophilic species has been reported. We report a retrospective observational study that included twenty-four children, who were diagnosed with tinea capitis due to anthropophilic species between 2004 and 2019. 75% of the patients were males with a mean age of 4,88 years. We observed 83,3% of cases from Africa, 4,2% from South America and 12,5% from Spain. Clinically, 70,8% of the patients presented scaly patches and non-scaring alopecia. Trichophyton soudanense was the main dermatophyte of the series (45,8%), followed by Microsporum audouinii (20,8%), Trichophyton tonsurans (12,5%) and Trichophyton violaceum (12,5%). Although this pattern of infection appears to be linked to immigration from Africa, we saw three native cases. The easier transmission of anthropophilic rather than zoophilic dermatophytes could predict a rise in the incidence of tinea capitis and a public health problem.

6.
Actas Dermosifiliogr ; 113(1): T74-T77, 2022 Jan.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-35249718

RESUMO

Although zoophilic dermatophytes remain the predominant cause of tinea capitis in Spain, an increase due to anthropophilic species has been reported. We report a retrospective observational study that included 24 children, who were diagnosed with tinea capitis due to anthropophilic species between 2004 and 2019. 75% of the patients were males with a mean age of 4,88 years. We observed 83,3% of cases from Africa, 4,2% from South America and 12,5% from Spain. Clinically, 70,8% of the patients presented scaly patches and non-scaring alopecia. Trichophyton soudanense was the main dermatophyte of the series (45,8%), followed by Microsporum audouinii (20,8%), Trichophyton tonsurans (12,5%) and Trichophyton violaceum (12,5%). Although this pattern of infection appears to be linked to immigration from Africa, we saw three native cases. The easier transmission of anthropophilic rather than zoophilic dermatophytes could predict a rise in the incidence of tinea capitis and a public health problem.

7.
Opt Lett ; 46(17): 4248-4251, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34469986

RESUMO

Plasmonic photothermal therapy (PPTT), as an increasingly studied treatment alternative, has been widely regarded mostly as a surface tissue treatment choice. Although some techniques have been implemented for interstitial tumors, these involve some grade of invasiveness, as the outer skin is usually broken to introduce light-delivering optical fibers or even catheters. In this work, we present a potential non-invasive strategy using the stereotactic approach, long employed in radiosurgery, by converging multiple near infrared laser beams for PPTT in tissue-equivalent optical phantoms that enclose small gel spheres and simulate interstitial tissue impregnated with plasmonic nanoparticles. The real-time in-depth monitoring of temperature increase is realized by an infrared camera face-on mounted over the phantom. Our results show that a significant reduction in the surface heating can be achieved with this configuration while remarkably increasing the interstitial reach of PPTT, assuring a ∼6∘C temperature increase for the simulated tumors at 10 mm depth and ∼4∘C at 15 mm depth and opening up new possibilities for future clinical applications.


Assuntos
Nanopartículas , Neoplasias , Ouro , Humanos , Lasers , Imagens de Fantasmas
8.
Eur J Neurol ; 28(2): 540-547, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33043545

RESUMO

BACKGROUND AND PURPOSE: B-type natriuretic peptide (BNP) and N-terminal pro-brain natriuretic peptide (NT-proBNP) are well-known surrogates of atrial fibrillation (AF) detection but studies usually present data on either BNP or NT-proBNP. The aim was to determine and directly compare the validity of the two biomarkers as a tool to predict AF and guide prolonged cardiac monitoring in cryptogenic stroke patients. METHODS: Non-lacunar acute ischaemic stroke (<72 h) patients over 55 years of age with cryptogenic stroke after standard evaluation were included in the Crypto-AF study and blood was collected. BNP and NT-proBNP levels were determined by automated immunoassays. AF was assessed by 28 days' monitoring. Highest (optimizing specificity) and lowest (optimizing sensitivity) quartiles were used as biomarker cut-offs to build predictive models adjusted by sex and age. The integrated discrimination improvement index (IDI) and DeLong test were used to compare the performance of the two biomarkers. RESULTS: From 320 patients evaluated, 218 were included in the analysis. AF was detected in 50 patients (22.9%). NT-proBNP (P < 0.001) and BNP (P < 0.001) levels were higher in subjects with AF and their levels correlated (r = 0.495, P < 0.001). BNP showed an increased area under the curve (0.720 vs. 0.669; P = 0.0218) and a better predictive capacity (IDI = 3.63%, 95% confidence interval 1.36%-5.91%) compared to NT-proBNP. BNP performed better than NT-proBNP in a specific model (IDI = 3.7%, 95% confidence interval 0.87%-6.5%), whilst both biomarkers performed similarly in the case of a sensitive model. CONCLUSIONS: Both BNP and NT-proBNP were increased in cryptogenic stroke patients with AF detection. Interestingly, BNP outperforms NT-proBNP, especially in terms of specificity.


Assuntos
Fibrilação Atrial , Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Fibrilação Atrial/complicações , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/epidemiologia , Biomarcadores , Humanos , Peptídeo Natriurético Encefálico , Fragmentos de Peptídeos , Acidente Vascular Cerebral/complicações
9.
Phys Rev Lett ; 124(21): 212501, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32530643

RESUMO

We report the first measurement of the (e,e^{'}p) three-body breakup reaction cross sections in helium-3 (^{3}He) and tritium (^{3}H) at large momentum transfer [⟨Q^{2}⟩≈1.9 (GeV/c)^{2}] and x_{B}>1 kinematics, where the cross section should be sensitive to quasielastic (QE) scattering from single nucleons. The data cover missing momenta 40≤p_{miss}≤500 MeV/c that, in the QE limit with no rescattering, equals the initial momentum of the probed nucleon. The measured cross sections are compared with state-of-the-art ab initio calculations. Overall good agreement, within ±20%, is observed between data and calculations for the full p_{miss} range for ^{3}H and for 100≤p_{miss}≤350 MeV/c for ^{3}He. Including the effects of rescattering of the outgoing nucleon improves agreement with the data at p_{miss}>250 MeV/c and suggests contributions from charge-exchange (SCX) rescattering. The isoscalar sum of ^{3}He plus ^{3}H, which is largely insensitive to SCX, is described by calculations to within the accuracy of the data over the entire p_{miss} range. This validates current models of the ground state of the three-nucleon system up to very high initial nucleon momenta of 500 MeV/c.

10.
Eur J Neurol ; 27(8): 1618-1624, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32347993

RESUMO

BACKGROUND AND PURPOSE: Covert paroxysmal atrial fibrillation (pAF) is the most frequent cause of cardiac embolism. Our goal was to discover parameters associated with early pAF detection with intensive cardiac monitoring. METHOD: Crypto-AF was a multicentre prospective study (four Comprehensive Stroke Centres) to detect pAF in non-lacunar cryptogenic stroke continuously monitored within the first 28 days. Stroke severity, infarct pattern, large vessel occlusion (LVO) at baseline, electrocardiography analysis, supraventricular extrasystolia in the Holter examination, left atrial volume index and brain natriuretic peptide level were assessed. The percentage of pAF detection and pAF episodes lasting more than 5 h were registered. RESULTS: Out of 296 patients, 264 patients completed the monitoring period with 23.1% (61/264) of pAF detection. Patients with pAF were older [odds ratio (OR) 1.04, 95% confidence interval (CI) 1.01-1.08], they had more haemorrhagic infarction (OR 4.03, 95% CI 1.44-11.22), they were more likely to have LVO (OR 4.29, 95% CI 2.31-7.97) (P < 0.0001), they had a larger left atrial volume index (OR 1.03, 95% CI 1.01-1.1) (P = 0.0002) and they had a higher level of brain natriuretic peptide (OR 1.01, 95% CI 1.0-1.1). Age and LVO were independently associated with pAF detection (OR 1.06, 95% CI 1.00-1.16, and OR 4.58, 95% CI 2.27- 21.38, respectively). Patients with LVO had higher cumulative incidence of pAF (log rank P < 0.001) and more percentage of pAF > 5 h [29.6% (21/71) vs. 8.3% (12/144); OR 4.62, 95% CI 2.11-10.08; P < 0.001]. In a mean follow-up of 26.82 months (SD 10.15) the stroke recurrence rate was 4.6% (12/260). CONCLUSIONS: Large vessel occlusion in cryptogenic stroke emerged as an independent marker of pAF.


Assuntos
Fibrilação Atrial , Acidente Vascular Cerebral , Fibrilação Atrial/complicações , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/epidemiologia , Eletrocardiografia , Eletrocardiografia Ambulatorial , Humanos , Incidência , Estudos Prospectivos
11.
World J Surg ; 44(11): 3868-3874, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32591841

RESUMO

BACKGROUND: Laparoscopic liver resections (LLR) have been increasingly performed in recent years. Most of the available evidence, however, comes from specialized centers in Asia, Europe and USA. Data from South America are limited and based on single-center experiences. To date, no multicenter studies evaluated the results of LLR in South America. The aim of this study was to evaluate the experience and results with LLR in South American centers. METHODS: From February to November 2019, a survey about LLR was conducted in 61 hepatobiliary centers in South America, composed by 20 questions concerning demographic characteristics, surgical data, and perioperative results. RESULTS: Fifty-one (83.6%) centers from seven different countries answered the survey. A total of 2887 LLR were performed, as follows: Argentina (928), Brazil (1326), Chile (322), Colombia (210), Paraguay (9), Peru (75), and Uruguay (8). The first program began in 1997; however, the majority (60.7%) started after 2010. The percentage of LLR over open resections was 28.4% (4.4-84%). Of the total, 76.5% were minor hepatectomies and 23.5% major, including 266 right hepatectomies and 343 left hepatectomies. The conversion rate was 9.7%, overall morbidity 13%, and mortality 0.7%. CONCLUSIONS: This is the largest study assessing the dissemination and results of LLR in South America. It showed an increasing number of centers performing LLR with the promising perioperative results, aligned with other worldwide excellence centers.


Assuntos
Laparoscopia , Neoplasias Hepáticas , Argentina , Ásia , Brasil , Chile , Colômbia , Europa (Continente) , Hepatectomia , Humanos , Fígado , Neoplasias Hepáticas/cirurgia , Peru
12.
Appl Opt ; 59(33): 10591-10598, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33361994

RESUMO

We present a new method to calculate the complex refractive index of spherical scatterers in a novel optical phantom developed by using homemade monodisperse silica nanospheres embedded into a polyester resin matrix and an ethanol-water mixture for applications in diffuse imaging. The spherical geometry of these nanoparticles makes them suitable for direct comparison between the values of the absorption and reduced scattering coefficients (µa and µs', respectively) obtained by the diffusion approximation solution to the transport equation from scattering measurements and those obtained by the Mie solution to Maxwell's equations. The values of the optical properties can be obtained by measuring, using an ultrafast detector, the time-resolved intensity distribution profiles of diffuse light transmitted through a thick slab of the silica nanosphere phantom, and by fitting them to the time-dependent diffusion approximation solution to the transport equation. These values can also be obtained by Mie solutions for spherical particles when their physical properties and size are known. By using scanning electron microscopy, we measured the size of these nanospheres, and the numerical results of µa and µs' can then be inferred by calculating the absorption and scattering efficiencies. Then we propose a numerical interval for the imaginary part of the complex refractive index of SiO2 nanospheres, ns, which is estimated by fixing the fitted values of µa and µs', using the known value of the real part of ns, and finding the corresponding value of Im(ns) that matches the optical parameters obtained by both methods finding values close to those reported for silica glass. This opens the possibility of producing optical phantoms with scattering and absorption properties that can be predicted and designed from precise knowledge of the physical characteristics of their constituents from a microscopic point of view.

13.
Pharmazie ; 75(7): 324-328, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32635974

RESUMO

Currently, cancer treatments are highly invasive, and they have been associated with a lot of adverse effects that put patient integrity at risk. Therefore, research of novel molecules and delivery systems capable of achieving a therapeutic effect that modifies inhibits and reduces the proliferative activity in cancer cells and, at the same time, reduce adverse effects associated with conventional therapies is imperative. In this study, we analyzed the biological effect of a novel cinnamic acid derivative, 3,4-dichlorobencil-p-phenoxylcilamide, in polymeric nanoparticles over MCF-7 breast cancer cells. The nanoparticulated system showed an inhibitory influence over cellular metabolism at equal or higher concentrations than 25 µM of 3,4-dichlorobencil-p-phenoxylcilamide, which is associated with PPARγ transcriptional activity, in addition to the decrease in the proliferation antigen Ki-67 basal levels. Those results position this kind of nanoscale system as an alternative on breast cancer treatment and lay the basis for research on the action mechanism associated with its cellular metabolism modulation and relationship with another hallmark on breast cancer cellular models.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Nanopartículas , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Antineoplásicos/administração & dosagem , Proliferação de Células/efeitos dos fármacos , Portadores de Fármacos/química , Feminino , Humanos , Antígeno Ki-67/metabolismo , Células MCF-7 , PPAR gama/metabolismo
14.
EMBO J ; 34(20): 2506-21, 2015 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-26254304

RESUMO

The PARK2 gene is mutated in 50% of autosomal recessive juvenile parkinsonism (ARJP) cases. It encodes parkin, an E3 ubiquitin ligase of the RBR family. Parkin exists in an autoinhibited state that is activated by phosphorylation of its N-terminal ubiquitin-like (Ubl) domain and binding of phosphoubiquitin. We describe the 1.8 Å crystal structure of human parkin in its fully inhibited state and identify the key interfaces to maintain parkin inhibition. We identify the phosphoubiquitin-binding interface, provide a model for the phosphoubiquitin-parkin complex and show how phosphorylation of the Ubl domain primes parkin for optimal phosphoubiquitin binding. Furthermore, we demonstrate that the addition of phosphoubiquitin leads to displacement of the Ubl domain through loss of structure, unveiling a ubiquitin-binding site used by the E2~Ub conjugate, thus leading to active parkin. We find the role of the Ubl domain is to prevent parkin activity in the absence of the phosphorylation signals, and propose a model for parkin inhibition, optimization for phosphoubiquitin recruitment, release of inhibition by the Ubl domain and engagement with an E2~Ub conjugate. Taken together, this model provides a mechanistic framework for activating parkin.


Assuntos
Ativação Enzimática/genética , Modelos Biológicos , Modelos Moleculares , Ubiquitina-Proteína Ligases/química , Ubiquitina-Proteína Ligases/metabolismo , Sítios de Ligação/genética , Calorimetria , Catálise , Cromatografia em Gel , Cristalização , Humanos , Ressonância Magnética Nuclear Biomolecular , Fosforilação , Conformação Proteica , Ubiquitina/metabolismo
15.
J Transl Med ; 17(1): 75, 2019 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-30871557

RESUMO

BACKGROUND: Extracellular vesicles (EVs) are small membrane-bound vesicles which play an important role in cell-to-cell communication. Their molecular cargo analysis is presented as a new source for biomarker detection, and it might provide an alternative to traditional solid biopsies. However, the most effective approach for EV isolation is not yet well established. RESULTS: Here, we study the efficiency of the most common EV isolation methods-ultracentrifugation, Polyethlyene glycol and two commercial kits, Exoquick® and PureExo®. We isolated circulating EVs from the bloodstream of healthy donors, characterized the size and yield of EVs and analyzed their protein profiles and concentration. Moreover, we have used for the first time Digital-PCR to identify and detect specific gDNA sequences, which has several implications for diagnostic and monitoring many types of diseases. CONCLUSIONS: Our findings present Polyethylene glycol precipitation as the most feasible and less cost-consuming EV isolation technique.


Assuntos
Ácidos Nucleicos Livres/isolamento & purificação , Vesículas Extracelulares/metabolismo , Polietilenoglicóis/farmacologia , Biomarcadores/metabolismo , Ácidos Nucleicos Livres/genética , Precipitação Química , Exossomos/metabolismo , Humanos , Tamanho da Partícula
16.
Phys Rev Lett ; 122(17): 172502, 2019 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-31107086

RESUMO

We measured the triple coincidence A(e,e^{'}np) and A(e,e^{'}pp) reactions on carbon, aluminum, iron, and lead targets at Q^{2}>1.5 (GeV/c)^{2}, x_{B}>1.1 and missing momentum >400 MeV/c. This was the first direct measurement of both proton-proton (pp) and neutron-proton (np) short-range correlated (SRC) pair knockout from heavy asymmetric nuclei. For all measured nuclei, the average proton-proton (pp) to neutron-proton (np) reduced cross-section ratio is about 6%, in agreement with previous indirect measurements. Correcting for single-charge exchange effects decreased the SRC pairs ratio to ∼3%, which is lower than previous results. Comparisons to theoretical generalized contact formalism (GCF) cross-section calculations show good agreement using both phenomenological and chiral nucleon-nucleon potentials, favoring a lower pp to np pair ratio. The ability of the GCF calculation to describe the experimental data using either phenomenological or chiral potentials suggests possible reduction of scale and scheme dependence in cross-section ratios. Our results also support the high-resolution description of high-momentum states being predominantly due to nucleons in SRC pairs.

17.
Pharmazie ; 74(7): 406-411, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31288896

RESUMO

The use of nanometric systems to deliver biologically active substances is a successful tool in different fields. In this study, we investigated nanometric systems with antioxidant capacity to modulate events associated with the redox state in human chondrocytes. We used nanoparticles (NPs) prepared with chitosan and glutathione (GSH) and an in vitro model: primary cultures of human chondrocytes were extracted from hyaline cartilage. The cells were exposed to CdCl2 in the presence or absence of NPs. CdCl2 is a widely known oxidizing agent. Fluorescence and confocal microscopy showed the location of the NPs within the cells. The results obtained showed that the NPs did not significantly affect cell viability. We studied the antioxidant capacity of the NPs by estimating the GSH, TBARs, and Cell Rox content and the enzymatic activity of glutathione peroxidase (GPx). In vitro assays showed that GSH levels, GPx activity and reactive oxygen species (Cell Rox) levels were modified with both concentrations of NPs, while lipoperoxidation (TBARs) decreased when cells exposed to CdCl2 were in contact with the NPs. All these results suggest the ability of NPs to modulate the cell redox state in a dose-dependent manner.


Assuntos
Antioxidantes/farmacologia , Quitosana/química , Glutationa/farmacologia , Nanopartículas , Estresse Oxidativo/efeitos dos fármacos , Antioxidantes/administração & dosagem , Cloreto de Cádmio/administração & dosagem , Cloreto de Cádmio/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Condrócitos/efeitos dos fármacos , Condrócitos/patologia , Relação Dose-Resposta a Droga , Glutationa/administração & dosagem , Humanos , Oxirredução
18.
Clin Exp Immunol ; 191(2): 229-239, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28963724

RESUMO

Itolizumab is a humanized anti-CD6 monoclonal antibody (mAb) that has previously shown encouraging results, in terms of safety and positive clinical effects, in a 6-week monotherapy clinical trial conducted in rheumatoid arthritis (RA) patients. The current Phase I study evaluated the safety and clinical response for a longer treatment of 12 itolizumab intravenous doses in subjects with active RA despite previous disease-modifying anti-rheumatic drug (DMARD) therapy. Twenty-one subjects were enrolled into four dosage groups (0·1, 0·2, 0·4 and 0·8 mg/kg). Efficacy end-points including American College of Rheumatology (ACR)20, ACR50 and ACR70 response rates and disease activity score in 28 joints (DAS28) were monitored at baseline and at specific time-points during a 10-week follow-up period. Itolizumab was well tolerated up to the highest tested dose. No related serious adverse events were reported and most adverse events were mild. Remarkably, itolizumab treatment did not produce lymphopenia and, therefore, was not associated with infections. All patients achieved a clinical response (ACR20) at least once during the study. Eleven subjects (55%) achieved at least a 20% improvement in ACR just 1 week after the first itolizumab administration. The clinical response was observed from the beginning of the treatment and was sustained during 24 weeks. The efficacy profile of this 12-week treatment was similar to that of the previous study (6-week treatment). These results reinforce the safety profile of itolizumab and provide further evidence on the clinical benefit from the use of this anti-CD6 mAb in RA patients.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Adolescente , Adulto , Idoso , Antígenos CD/imunologia , Antígenos de Diferenciação de Linfócitos T/imunologia , Cuba , Progressão da Doença , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Feminino , Seguimentos , Humanos , Linfopenia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
19.
Phys Rev Lett ; 121(9): 092501, 2018 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-30230869

RESUMO

Short-range correlated (SRC) nucleon pairs are a vital part of the nucleus, accounting for almost all nucleons with momentum greater than the Fermi momentum (k_{F}). A fundamental characteristic of SRC pairs is having large relative momenta as compared to k_{F}, and smaller center of mass (c.m.) which indicates a small separation distance between the nucleons in the pair. Determining the c.m. momentum distribution of SRC pairs is essential for understanding their formation process. We report here on the extraction of the c.m. motion of proton-proton (pp) SRC pairs in carbon and, for the first time in heavier and ansymetric nuclei: aluminum, iron, and lead, from measurements of the A(e,e^{'}pp) reaction. We find that the pair c.m. motion for these nuclei can be described by a three-dimensional Gaussian with a narrow width ranging from 140 to 170 MeV/c, approximately consistent with the sum of two mean-field nucleon momenta. Comparison with calculations appears to show that the SRC pairs are formed from mean-field nucleons in specific quantum states.

20.
Genetica ; 146(6): 505-515, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30361962

RESUMO

We assessed the presence of independent evolving lineages of the trahira, Hoplias malabaricus, one of the few freshwater fish species having wide distribution in the Neotropics which is the region with the highest global diversity of freshwater fish. To achieve that goal, 58 mitochondrial sequences of cytochrome c oxidase subunit I (COI; DNA barcoding) were generated from collected samples and 85 obtained from public databases, which were analyzed in comparison to chromosomal and geological data. The magnitude of genetic diversity found among different sampling sites was greater than 2%. Molecular species delimitation methods indicated the existence of a least four distinct lineages. The recognised cytotypes did not form monophyletic groups, suggesting that the karyotypic macrostructure could be a homoplastic character. The haplotype relationships suggested secondary contacts between the ecoregions of Northern and Northeastern Brazil that were shaped by coastal routes between adjacent watersheds during the Pleistocene epoch and probable exchanges of their ichthyofaunas. Our results indicated that multiple factors have driven the diversification of H. malabaricus, from ancient geological events linked to the reactivation of tectonic faults to more recent occurrences related to eustatic changes in ocean levels. Ultimately, the magnitude of its genetic diversity suggests the necessity of revising its taxonomic status.


Assuntos
Caraciformes/genética , Evolução Molecular , Filogenia , Animais , Caraciformes/classificação , Código de Barras de DNA Taxonômico , Complexo IV da Cadeia de Transporte de Elétrons/genética , Proteínas de Peixes/genética , Haplótipos , Cariótipo , Filogeografia
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