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1.
ACS Nano ; 18(8): 6523-6532, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38369724

RESUMO

Scanning-probe and wide-field magnetic microscopes based on nitrogen-vacancy (NV) centers in diamond have enabled advances in the study of biology and materials, but each method has drawbacks. Here, we implement an alternative method for nanoscale magnetic microscopy based on optical control of the charge state of NV centers in a dense layer near the diamond surface. By combining a donut-beam super-resolution technique with optically detected magnetic resonance spectroscopy, we imaged the magnetic fields produced by single 30 nm iron-oxide nanoparticles. The magnetic microscope has a lateral spatial resolution of ∼100 nm, and it resolves the individual magnetic dipole features from clusters of nanoparticles with interparticle spacings down to ∼190 nm. The magnetic feature amplitudes are more than an order of magnitude larger than those obtained by confocal magnetic microscopy due to the narrower optical point-spread function and the shallow depth of NV centers. We analyze the magnetic nanoparticle images and sensitivity as a function of the microscope's spatial resolution and show that the signal-to-noise ratio for nanoparticle detection does not degrade as the spatial resolution improves. We identify sources of background fluorescence that limit the present performance, including diamond second-order Raman emission and imperfect NV charge state control. Our method, which uses <10 mW laser power and can be parallelized by patterned illumination, introduces a promising format for nanoscale magnetic imaging.

2.
ArXiv ; 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37873018

RESUMO

Scanning-probe and wide-field magnetic microscopes based on Nitrogen-Vacancy (NV) centers in diamond have enabled remarkable advances in the study of biology and materials, but each method has drawbacks. Here, we implement an alternative method for nanoscale magnetic microscopy based on optical control of the charge state of NV centers in a dense layer near the diamond surface. By combining a donut-beam super-resolution technique with optically detected magnetic resonance spectroscopy, we imaged the magnetic fields produced by single 30-nm iron-oxide nanoparticles. The magnetic microscope has a lateral spatial resolution of ~100 nm, and it resolves the individual magnetic dipole features from clusters of nanoparticles with interparticle spacings down to ~190 nm. The magnetic feature amplitudes are more than an order of magnitude larger than those obtained by confocal magnetic microscopy due to the smaller characteristic NV-nanoparticle distance within nearby sensing voxels. We analyze the magnetic point-spread function and sensitivity as a function of the microscope's spatial resolution and identify sources of background fluorescence that limit the present performance, including diamond second-order Raman emission and imperfect NV charge-state control. Our method, which uses less than 10 mW laser power and can be parallelized by patterned illumination, introduces a new format for nanoscale magnetic imaging.

3.
Front Cell Infect Microbiol ; 13: 1241305, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37674581

RESUMO

Maintenance of dNTPs pools in Trypanosoma brucei is dependent on both biosynthetic and degradation pathways that together ensure correct cellular homeostasis throughout the cell cycle which is essential for the preservation of genomic stability. Both the salvage and de novo pathways participate in the provision of pyrimidine dNTPs while purine dNTPs are made available solely through salvage. In order to identify enzymes involved in degradation here we have characterized the role of a trypanosomal SAMHD1 orthologue denominated TbHD82. Our results show that TbHD82 is a nuclear enzyme in both procyclic and bloodstream forms of T. brucei. Knockout forms exhibit a hypermutator phenotype, cell cycle perturbations and an activation of the DNA repair response. Furthermore, dNTP quantification of TbHD82 null mutant cells revealed perturbations in nucleotide metabolism with a substantial accumulation of dATP, dCTP and dTTP. We propose that this HD domain-containing protein present in kinetoplastids plays an essential role acting as a sentinel of genomic fidelity by modulating the unnecessary and detrimental accumulation of dNTPs.


Assuntos
Proteína 1 com Domínio SAM e Domínio HD , Trypanosoma brucei brucei , Desoxirribonucleotídeos/metabolismo , Trypanosoma brucei brucei/citologia , Trypanosoma brucei brucei/enzimologia , Trypanosoma brucei brucei/genética , Trypanosoma brucei brucei/metabolismo , Proteína 1 com Domínio SAM e Domínio HD/genética , Proteína 1 com Domínio SAM e Domínio HD/metabolismo , Instabilidade Genômica , Genoma de Protozoário , Dano ao DNA , Ciclo Celular
4.
Sci Adv ; 9(24): eadh3189, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37327342

RESUMO

Radio frequency (RF) magnetometers based on nitrogen vacancy centers in diamond are predicted to offer femtotesla sensitivity, but previous experiments were limited to the picotesla level. We demonstrate a femtotesla RF magnetometer using a diamond membrane inserted between ferrite flux concentrators. The device provides ~300-fold amplitude enhancement for RF magnetic fields from 70 kHz to 3.6 MHz, and the sensitivity reaches ~70 fT√s at 0.35 MHz. The sensor detected the 3.6-MHz nuclear quadrupole resonance (NQR) of room-temperature sodium nitrite powder. The sensor's recovery time after an RF pulse is ~35 µs, limited by the excitation coil's ring-down time. The sodium-nitrite NQR frequency shifts with temperature as -1.00±0.02 kHz/K, the magnetization dephasing time is T2*=887±51 µs, and multipulse sequences extend the signal lifetime to 332±23 ms, all consistent with coil-based studies. Our results expand the sensitivity frontier of diamond magnetometers to the femtotesla range, with potential applications in security, medical imaging, and materials science.


Assuntos
Diamante , Nitrogênio , Espectroscopia de Ressonância Magnética/métodos , Temperatura
5.
Phys Rev Appl ; 19(6)2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38716475

RESUMO

We measure electron- and nuclear-spin transition frequencies in the ground state of nitrogen-vacancy (N-V) centers in diamond for two nitrogen isotopes (14N-V and 15N-V) over temperatures ranging from 77 to 400 K. Measurements are performed using Ramsey interferometry and direct optical readout of the nuclear and electron spins. We extract coupling parameters Q (for 14N-V), D, A‖, A⊥, and γe/γn, and their temperature dependences for both isotopes. The temperature dependences of the nuclear-spin transitions within the ms=0 spin manifold near room temperature are found to be 0.52(1) ppm/K for 14N-V(|mI = -1⟩ ↔ |mI = +1⟩) and -1.1(1) ppm/K for 15N-V(|mI = -1/2⟩ ↔ |mI = +1/2⟩). An isotopic shift in the zero-field splitting parameter D between 14N-V and 15N-V is measured to be ~ 120 kHz. Residual transverse magnetic fields are observed to shift the nuclear-spin transition frequencies, especially for 15N-V. We have precisely determined the set of parameters relevant for the development of nuclear-spin-based diamond quantum sensors with greatly reduced sensitivity to environmental factors.

6.
Pharmaceuticals (Basel) ; 15(11)2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36422551

RESUMO

Background. Research studies indicate that immunization with protein extracts of Trypanosoma cruzi, the protozoan parasite that causes Chagas disease, prevents the appearance of tumors in 60% of mice injected with the murine lung carcinoma tumor line. The molecular basis of this process is unknown, although the presence of specific antigens in tumor cells and on the surface of T. cruzi suggests an antiparasitic immune response, with an effective cross-reaction against cancer cells, hence the importance to identify the antigens involved and determine their potential as target cells in anticancer therapy. Aim. This study aimed to determine the presence of antigenic proteins of T. cruzi shared with acute lymphoblastic leukemia and neuroblastoma cells. Material and methods. To achieve this, polyclonal antibodies against T. cruzi were developed in rabbits, and reactivity was determined with protein extracts of acute lymphoblastic leukemia cells and neuroblastoma. The immunodetection of five different strains of T. cruzi against anti-T. cruzi polyclonal antibodies was also performed. Conclusion. The study allows the knowledge of the immunological interactions between cancer and parasites to be expanded and, therefore, contributes to the design of more and better projects that improve the therapeutic strategies applied in oncology.

7.
Sci Adv ; 7(43): eabl3840, 2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34678066

RESUMO

We demonstrate the operation of a rotation sensor based on the nitrogen-14 (14N) nuclear spins intrinsic to nitrogen-vacancy (NV) color centers in diamond. The sensor uses optical polarization and readout of the nuclei and a radio-frequency double-quantum pulse protocol that monitors 14N nuclear spin precession. This measurement protocol suppresses the sensitivity to temperature variations in the 14N quadrupole splitting, and it does not require microwave pulses resonant with the NV electron spin transitions. The device was tested on a rotation platform and demonstrated a sensitivity of 4.7°/s (13 mHz/Hz), with a bias stability of 0.4 °/s (1.1 mHz).

8.
J Acoust Soc Am ; 150(1): 646, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34340463

RESUMO

Polymeric separators have been developed since 2010 to produce acoustophoretic separation of particles or cells in suspension with high efficiency. They rely on three-dimensional (3D) resonances of their whole structure actuated by ultrasounds. In this paper, a numerical 3D analysis is presented and validated as the only tool for optimization of these polymeric chips to perform efficient separation applications. In contrast to conventional acoustophoretic techniques based on the establishment of standing waves in the liquid phase of the channel (requiring rigid chip materials, such as silicon or glass), whole-structure resonances of the chip allow the use of materials that are acoustically soft and of low acoustic impedance, which is close to that of the liquid samples hosted. The resonance requirement is not restricted to the liquid phase in the polymeric chips, but it extends to the 3D whole structure, allowing any material. It provides significant advantages in the design and manufacture of our chips, allowing the use of low-cost materials and cheap manufacturing processes and even printing of devices. The extraordinary complexity of their multiple resonances requires theoretical approaches to optimize their acoustophoretic performance. Hence, the importance of 3D numerical analyses, which are capable of predicting the acoustic behavior of these chips, is to perform acoustophretica separation in suspensions.

9.
ACS Infect Dis ; 7(2): 318-332, 2021 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-33417760

RESUMO

The maintenance of deoxyribonucleotide triphosphate (dNTP) homeostasis through synthesis and degradation is critical for accurate genomic and mitochondrial DNA replication fidelity. Trypanosoma brucei makes use of both the salvage and de novo pathways for the provision of pyrimidine dNTPs. In this respect, the sterile α motif and histidine-aspartate domain-containing protein 1 (SAMHD1) appears to be the most relevant dNTPase controlling dNTP/deoxynucleoside homeostasis in mammalian cells. Here, we have characterized the role of a unique trypanosomal SAMHD1 orthologue denominated TbHD52. Our results show that TbHD52 is a mitochondrial enzyme essential in bloodstream forms of T. brucei. Knockout cells are pyrimidine auxotrophs that exhibit strong defects in genomic integrity, cell cycle progression, and nuclear DNA and kinetoplast segregation in the absence of extracellular thymidine. The lack of TbHD52 can be counteracted by the overexpression of human dCMP deaminase, an enzyme that is directly involved in dUMP formation yet absent in trypanosomes. Furthermore, the cellular dNTP quantification and metabolomic analysis of TbHD52 null mutants revealed perturbations in the nucleotide metabolism with a substantial accumulation of dCTP and cytosine-derived metabolites while dTTP formation was significantly reduced. We propose that this HD-domain-containing protein unique to kinetoplastids plays an essential role in pyrimidine dNTP homeostasis and contributes to the provision of deoxycytidine required for cellular dTTP biosynthesis.


Assuntos
Trypanosoma brucei brucei , Animais , Homeostase , Humanos , Mitocôndrias , Pirimidinas , Proteína 1 com Domínio SAM e Domínio HD/genética , Trypanosoma brucei brucei/genética
10.
Phys Rev Res ; 2(2)2020.
Artigo em Inglês | MEDLINE | ID: mdl-33117992

RESUMO

Magnetometers based on nitrogen-vacancy (NV) centers in diamond are promising room-temperature, solid-state sensors. However, their reported sensitivity to magnetic fields at low frequencies (≾1 kHz) is presently ≿10 pT s1/2, precluding potential applications in medical imaging, geoscience, and navigation. Here we show that high-permeability magnetic flux concentrators, which collect magnetic flux from a larger area and concentrate it into the diamond sensor, can be used to improve the sensitivity of diamond magnetometers. By inserting an NV-doped diamond membrane between two ferrite cones in a bowtie configuration, we realize a ~250-fold increase of the magnetic field amplitude within the diamond. We demonstrate a sensitivity of ~0.9 pT s1/2 to magnetic fields in the frequency range between 10 and 1000 Hz. This is accomplished using a dual-resonance modulation technique to suppress the effect of thermal shifts of the NV spin levels. The magnetometer uses 200 mW of laser power and 20 mW of microwave power. This work introduces a new degree of freedom for the design of diamond sensors by using structured magnetic materials to manipulate magnetic fields.

11.
Transplantation ; 104(4): e90-e97, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31880751

RESUMO

BACKGROUND: Although return of function has been reported in patients undergoing proximal forearm transplantations (PFTs), reports of long-term function are limited. In this study, we evaluated the clinical progress and function 7 years postoperatively in a patient who underwent bilateral PFT. CASE PRESENTATION: A 58-year-old man underwent bilateral PFT in May 2012. Transplantation involved all of the flexor and extensor muscles of the forearm. Neurorrhaphies of the median, ulnar, and radial nerves were epineural and 7 cm proximal to the elbow. Immunosuppressive maintenance medications during the first 3 years postoperatively were tacrolimus, mycophenolate, and steroids, and later, tacrolimus, sirolimus, and steroids. Forearm function was evaluated annually using the Disabilities of the Arm, Shoulder, and Hand; Carroll; Hand Transplantation Score System; Short Form-36; and Kapandji scales. We also evaluated his grip and pinch force. RESULTS: Postoperatively, the patient developed hypertriglyceridemia and systemic hypertension. He experienced 6 acute rejections, and none were resistant to steroids. Motor function findings in his right/left hand were: grip strength: 10/13 kg; key pinch: 3/3 kg; Kapandji score: 6/9 of 10; Carroll score: 66/80; Hand Transplantation Score System score: 90/94. His preoperative Disabilities of the Arm, Shoulder, and Hand score was 50 versus 18, postoperatively; his Short Form-36 score was 90. This function improved in relation with the function reported in the second year. CONCLUSIONS: Seven years following PFT, the patient gained limb strength with a functional elbow and wrist, although with diminished digital dexterity and sensation. Based on data presented by other programs and our own experience, PFT is indicated for select patients.


Assuntos
Antebraço/inervação , Antebraço/cirurgia , Sobrevivência de Enxerto , Transplante de Órgãos , Avaliação da Deficiência , Rejeição de Enxerto/tratamento farmacológico , Rejeição de Enxerto/imunologia , Humanos , Imunossupressores/administração & dosagem , Masculino , Pessoa de Meia-Idade , Atividade Motora , Força Muscular , Recuperação de Função Fisiológica , Sensação , Fatores de Tempo , Resultado do Tratamento
12.
Parasitology ; 146(14): 1743-1754, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31603063

RESUMO

Kinetoplastid parasites are responsible for serious diseases in humans and livestock such as Chagas disease and sleeping sickness (caused by Trypanosoma cruzi and Trypanosoma brucei, respectively), and the different forms of cutaneous, mucocutaneous and visceral leishmaniasis (produced by Leishmania spp). The limited number of antiparasitic drugs available together with the emergence of resistance underscores the need for new therapeutic agents with novel mechanisms of action. The use of agents binding to surface glycans has been recently suggested as a new approach to antitrypanosomal design and a series of peptidic and non-peptidic carbohydrate-binding agents have been identified as antiparasitics showing efficacy in animal models of sleeping sickness. Here we provide an overview of the nature of surface glycans in three kinetoplastid parasites, T. cruzi, T. brucei and Leishmania. Their role in virulence and host cell invasion is highlighted with the aim of identifying specific glycan-lectin interactions and carbohydrate functions that may be the target of novel carbohydrate-binding agents with therapeutic applications.


Assuntos
Antiparasitários/farmacologia , Carboidratos/imunologia , Interações Hospedeiro-Parasita/efeitos dos fármacos , Gado/parasitologia , Polissacarídeos/imunologia , Animais , Doença de Chagas/tratamento farmacológico , Desenho de Fármacos , Humanos , Leishmania/efeitos dos fármacos , Leishmania/patogenicidade , Camundongos , Trypanosoma cruzi/efeitos dos fármacos , Trypanosoma cruzi/patogenicidade , Tripanossomíase Africana/tratamento farmacológico
13.
mSphere ; 4(4)2019 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-31391279

RESUMO

Cytidine deaminase (CDA) is a pyrimidine salvage enzyme that catalyzes cytidine and deoxycytidine hydrolytic deamination to yield uridine and deoxyuridine. Here we report the biochemical characterization of Trypanosoma brucei CDA as an enzyme within the tetrameric class of the CDA family that efficiently deaminates cytidine, deoxycytidine, and the nucleoside analogue 5-methyl-2'-deoxycytidine. In line with previous studies, we show that RNA interference (RNAi)-mediated CDA depletion impairs T. brucei proliferation when grown in pyrimidine-deficient medium, while supplementation with thymidine or deoxyuridine restores growth, further underscoring the role of this enzyme in providing deoxyuridine for dUMP formation via thymidine kinase, the substrate required for de novo thymidylate biosynthesis. This observation contrasts with the existence in T. brucei of a dimeric deoxyuridine 5'-triphosphate nucleotidohydrolase (dUTPase), an essential enzyme that can produce dUMP via the hydrolysis of dUTP/dUDP. Thus, T. brucei dUTPase-null mutants are thymidine auxotrophs, suggesting that dUTPase might have a role in providing dUMP for thymidylate biosynthesis. We show that overexpression of human dCMP deaminase (DCTD), an enzyme that provides directly dUMP through dCMP deamination, does not reverse the lethal phenotype of dUTPase knockout cells, which further supports the notion that in T. brucei, CDA is uniquely involved in providing dUMP, while the main role of dUTPase would be the withdrawal of the excess of dUTP to avoid its incorporation into DNA. Furthermore, we report the mitochondrial localization of CDA, highlighting the importance of this organelle in pyrimidine metabolism.IMPORTANCE Cytidine deaminases (CDAs) catalyze the hydrolytic deamination of cytidine and deoxycytidine in the pyrimidine salvage pathway. In kinetoplastids, pyrimidine metabolism has been extensively studied as a source of potential drug targets, given the fact that many of the enzymes of the pathway are essential. Thymidylate (dTMP) synthesis in Trypanosoma brucei exhibits unique characteristics. Thus, it has been suggested that the production of dUMP, the substrate for dTMP formation, is solely dependent on cytidine deaminase and thymidine kinase. Here we characterize recombinant T. brucei CDA (TbCDA) and present evidence that indeed the alternative route for dUMP formation via deoxyuridine 5'-triphosphate nucleotidohydrolase does not have a prominent role in de novo dTMP formation. Furthermore, we provide a scheme for the compartmentalization of dTMP biosynthesis, taking into account the observation that CDA is located in the mitochondrion, together with available information on the intracellular localization of other enzymes involved in the dTTP biosynthetic pathway.


Assuntos
Citidina Desaminase/metabolismo , Proteínas de Protozoários/metabolismo , Timidina Monofosfato/biossíntese , Trypanosoma brucei brucei/enzimologia , Citidina Desaminase/genética , DCMP Desaminase/genética , Técnicas de Silenciamento de Genes , Humanos , Cinética , Proteínas de Protozoários/genética , Pirimidinas/metabolismo , Interferência de RNA , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Nucleotídeos de Timina/metabolismo , Trypanosoma brucei brucei/genética
14.
Biosci. j. (Online) ; 35(4): 1245-1255, july/aug. 2019. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-1048928

RESUMO

This study aimed to evaluate how the surrounding vegetation affects the assemblage of fruit flies. For this, flies were collected in guava orchards with distinct types of surrounding vegetation (exotic pasture, native forest and fruit tree intercropping). The experiment was conducted in Itaporã and Dourados, State of Mato Grosso do Sul, Brazil. Weekly samples were collected from March to April 2015. McPhail traps were baited with 5% hydrolyzed corn protein. Species richness, diversity index and abundance were evaluated for each orchard, as well as the species composition of fruit fly between the environments surrounding the orchard and, finally, the sex ratio. A total of 579 individuals were collected of the species Anastrepha fraterculus, A. montei, A. obliqua, A. sororcula, A. striata, A. turpiniae and A. zenildae. The orchard surrounded by native forest had the highest species richness and Shannon diversity. The species composition differed between environments, with the formation of three distinct groups. The environment surrounding the guava orchard influences the richness, diversity, abundance and sex ratio of fruit flies, indicating that the native forest may provide more resources for the maintenance of these insects.


Este estudo teve como objetivo avaliar como a vegetação do entorno dos pomares afeta a assembleia de moscas-das-frutas. Para isto, foram coletadas moscas em pomares de goiabeiras com distintos tipos de vegetação no entorno (pastagens exóticas, mata nativa e fruticultura). O experimento foi conduzido em Itaporã e Dourados, Estado do Mato Grosso do Sul, Brasil. Amostras semanais foram coletadas de março a abril de 2015. As armadilhas McPhail foram iscadas com 5% de proteína hidrolisada de milho. A riqueza de espécies, o índice de diversidade e a abundância foram avaliados para cada pomar, assim como a composição de espécies de moscas-das-frutas entre os ambientes do entorno do pomar e razão sexual. Um total de 579 indivíduos foram coletados das espécies Anastrepha fraterculus, A. montei, A. obliqua, A. sororcula, A. striata, A. turpiniae e A. zenildae. O pomar cercado por mata nativa apresentou maior riqueza de espécies e diversidade de Shannon. A composição das espécies diferiu entre os ambientes, com a formação de três grupos distintos. O ambiente do entorno do pomar de goiabeira influencia a riqueza, diversidade, abundância e razão sexual das moscas-das-frutas, indicando que a mata nativa pode fornecer mais recursos para a manutenção desses insetos.


Assuntos
Ecossistema , Tephritidae , Psidium , Drosophila
15.
Sci Adv ; 5(7): eaaw7895, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31360769

RESUMO

Quantum sensors based on nitrogen-vacancy centers in diamond have emerged as a promising detection modality for nuclear magnetic resonance (NMR) spectroscopy owing to their micrometer-scale detection volume and noninductive-based detection. A remaining challenge is to realize sufficiently high spectral resolution and concentration sensitivity for multidimensional NMR analysis of picoliter sample volumes. Here, we address this challenge by spatially separating the polarization and detection phases of the experiment in a microfluidic platform. We realize a spectral resolution of 0.65 ± 0.05 Hz, an order-of-magnitude improvement over previous diamond NMR studies. We use the platform to perform two-dimensional correlation spectroscopy of liquid analytes within an effective ∼40-picoliter detection volume. The use of diamond quantum sensors as in-line microfluidic NMR detectors is a major step toward applications in mass-limited chemical analysis and single-cell biology.

16.
An. Fac. Cienc. Méd. (Asunción) ; 52(2): 49-52, 20190700.
Artigo em Espanhol | LILACS, BDNPAR | ID: biblio-1007033

RESUMO

Introducción: El tabaquismo es una de las principales causas de enfermedad y muerte en el mundo, y su consumo puede aumentar ante situaciones de estrés. Objetivos: Caracterizar el tabaquismo dentro de la cárcel de mujeres Casa del Buen Pastor. Materiales y métodos: Estudio observacional, descriptivo, de corte transversal con una encuesta anónima utilizando el método de múltiple opción de respuestas. Resultados: Declararon ser fumadoras 73 de las 101 internas encuestadas, y la gran mayoría de ellas quiere dejar de fumar. Conclusión: Hay una alta prevalencia de tabaquismo entre las mujeres en prisión, y su mayoritario deseo de cesación es una oportunidad que debe aprovecharse para apoyarlas con medidas adecuadas para lograrlo.


Introduction: Smoking is one of the main causes of disease and death in the world, and its consumption may increase in situations of stress. Objectives: To characterize smoking within the Casa del Buen Pastor women's prison. Materials and methods: Observational, descriptive, cross-sectional study with an anonymous survey using the method of multiple choice of answers. Results: 73 of the 101 inmates surveyed declared themselves to be smokers, and the vast majority of them want to quit smoking. Conclusion: There is a high prevalence of smoking among women in prison, and their majority desire for cessation is an opportunity that should be used to support them with appropriate measures to achieve it.


Assuntos
Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Prisões , Tabagismo/epidemiologia , Mulheres , Paraguai/epidemiologia , Grupos de Risco , Prevalência
17.
Phys Rev Appl ; 11(3)2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31245433

RESUMO

Magnetic microscopy of malarial hemozoin nanocrystals is performed by optically detected magnetic resonance imaging of near-surface diamond nitrogen-vacancy centers. Hemozoin crystals are extracted from Plasmodium falciparum-infected human blood cells and studied alongside synthetic hemozoin crystals. The stray magnetic fields produced by individual crystals are imaged at room temperature as a function of the applied field up to 350 mT. More than 100 nanocrystals are analyzed, revealing the distribution of their magnetic properties. Most crystals (96%) exhibit a linear dependence of the stray-field magnitude on the applied field, confirming hemozoin's paramagnetic nature. A volume magnetic susceptibility of 3.4 × 10-4 is inferred with use of a magnetostatic model informed by correlated scanning-electron-microscopy measurements of crystal dimensions. A small fraction of nanoparticles (4/82 for Plasmodium falciparum-produced nanoparticles and 1/41 for synthetic nanoparticles) exhibit a saturation behavior consistent with superparamagnetism. Translation of this platform to the study of living Plasmodium-infected cells may shed new light on hemozoin formation dynamics and their interaction with antimalarial drugs.

18.
Opt Express ; 27(2): 1706-1717, 2019 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-30696232

RESUMO

We propose a hybrid laser system consisting of a semiconductor external cavity laser associated to an intra-cavity diamond etalon doped with nitrogen-vacancy color centers. We consider laser emission tuned to the infrared absorption line that is enhanced under the magnetic field dependent nitrogen-vacancy electron spin resonance and show that this architecture leads to a compact solid-state magnetometer that can be operated at room-temperature. The sensitivity to the magnetic field limited by the photonshot-noise of the output laser beam is estimated to be less than 1 pT/Hz. Unlike usual NV center infrared magnetometry, this method would not require an external frequency stabilized laser. Since the proposed system relies on the competition between the laser threshold and an intracavity absorption, such laser-based optical sensor could be easily adapted to a broad variety of sensing applications based on absorption spectroscopy.

19.
Am J Cardiol ; 123(6): 865-873, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30598243

RESUMO

Poor dietary patterns are associated with coronary artery disease (CAD) and cardiovascular events. The aim of this study was to determine whether reported dietary patterns change after undergoing invasive coronary angiography. Participants without a history of coronary revascularization were prospectively enrolled before undergoing coronary angiography at a tertiary center between February 2015 and February 2017. Enrolled participants completed the Rate Your Plate (RYP) survey at baseline (before angiography), 1-month, and 6-month follow-ups. RYP scores range from 24 to 72 (higher scores indicate healthier dietary patterns) are presented as median (interquartile range), and are compared from baseline to follow-up using a nonparametric related-sample test. No dietary guidance was given outside of usual care. Of the 400 participants, 326 (82%) completed at least 1 follow-up survey with no differences in baseline characteristics of participants who had at least 1 versus no follow-up survey. The median RYP score significantly improved from baseline (53 [47 to 57]) to 1-month (58 [52 to 62]) and 6-month (59 [54 to 63]) follow-ups (p <0.001). Angiography demonstrated severe CAD in 125 (38%) and normal or nonobstructive CAD in 201 (62%) participants. RYP scores significantly improved over time in both groups (p <0.001), but the percent change in RYP score over time was greater in participants with versus without severe CAD (13.9% [5.8 to 22.5] vs 9.6% [4.8 to 19.1], p = 0.03). In conclusion, self-reported dietary patterns improved after invasive coronary angiography, particularly in the subset with CAD. Future studies to determine how best to utilize the periprocedural period to further improve dietary patterns in this population are warranted.


Assuntos
Atitude Frente a Saúde , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico , Vasos Coronários/diagnóstico por imagem , Dieta Saudável , Medição de Risco/métodos , Idoso , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/prevenção & controle , Progressão da Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Morbidade/tendências , Estudos Prospectivos , Fatores de Risco , Índice de Gravidade de Doença , Taxa de Sobrevida/tendências , Estados Unidos/epidemiologia
20.
Appl Neuropsychol Child ; 8(1): 15-23, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-28956632

RESUMO

The aim of this study was twofold: first, to obtain a neuropsychological characterization of children with language disorders, and second, to evaluate the effectiveness of an intervention program on working memory. We used a pretest-instruction-posttest design, carefully identifying a sample of 32 children with language disorders whom we then evaluated for short-term verbal and visuospatial memory, verbal and visuospatial working memory, attention, processing speed, and lexical-semantic skills. We then implemented an intervention program on working memory consisting of 72 sessions of 15 minutes each, after which we repeated the neuropsychological assessment of these functions. Children with language disorders performed worse than children in the control group in all memory tasks evaluated and in the lexical-semantic processing task. After the intervention, children with language disorders showed a significant increase over their own previous performance in all variables. Children with language disorders show significant cognitive deficits and not just linguistic impairment. We offer conclusive findings on the effectiveness of the intervention program used. Finally, we obtained partial support for the existence of a causal link between improved performance on memory tasks and performance in a lexical-semantic task.


Assuntos
Remediação Cognitiva/métodos , Transtornos da Linguagem/reabilitação , Memória de Curto Prazo/fisiologia , Avaliação de Resultados em Cuidados de Saúde , Fonoterapia/métodos , Criança , Pré-Escolar , Feminino , Humanos , Transtornos da Linguagem/diagnóstico , Masculino , Testes Neuropsicológicos
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