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1.
J Photochem Photobiol B ; 236: 112587, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36283255

RESUMO

Nanoemulsions are increasingly gaining importance in the development of topically applied medicine and cosmetic products because their small droplets favor the penetration rates of active compounds into the body. In this scenario, the measurements of their diffusion rates as well as eventual physicochemical changes in the target tissues are of utmost importance. It is also recognized that the use of natural surfactants can avoid allergic reactions as frequently observed for synthetic products. The natural saponins extracted from Sapindus Saponaria have the property of forming foam and are exploited as biocompatible and biodegradable, while cellulose nanocrystals are known to increase the stability of a formulation avoiding the coalescence of drops at the interface. Therefore, nanoemulsions combining natural saponins and cellulose nanocrystals are promising systems that may facilitate greater diffusion rates of molecules into the skin, being candidates to substitute synthetic formulations. This study applied the Photoacoustic Spectroscopy technique to measure the diffusion rates and the physicochemical properties of nanoemulsified formulations containing saponins and cellulose nanocrystals topically applied to the skin. The ex vivo study combined the first-time photoacoustic measurements performed in both ultraviolet-visible and mid-infrared spectral regions. The toxicity of these formulations in L929 cells was also evaluated. The results showed that the formulations were able to propagate throughout the skin to a depth of approximately 756 µm, reaching the dermal side. The non-observation of absorbing band shifting or new bands in the FTIR spectra suggests that there were no structural changes in the skin as well as in the formulations after the nanoemulsions administration. The cytotoxicity results showed that the increase of cellulose nanocrystals concentration decreased cellular toxicity. In conclusion, the results demonstrated the advantage of combining photoacoustic methods in the ultraviolet-visible and mid-infrared spectral regions to analyze drug diffusion and interaction with the skin tissues. Both methods complement each other, allowing the confirmation of the nanoemulsion diffusion through the skin and also suggesting there were no detectable physicochemical changes in the tissues. Formulations stabilized with saponins and cellulose nanocrystals showed great potential for the development of topically administered cosmetics and drugs.


Assuntos
Nanopartículas , Saponinas , Espectroscopia de Infravermelho com Transformada de Fourier , Celulose , Saponinas/farmacologia , Nanopartículas/química , Preparações Farmacêuticas , Emulsões/química
2.
Braz J Med Biol Res ; 54(3): e9571, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33470396

RESUMO

Cancer cell lines are widely used as in vitro models of tumorigenesis, facilitating fundamental discoveries in cancer biology and translational medicine. Currently, there are few options for glioblastoma (GBM) treatment and limited in vitro models with accurate genomic and transcriptomic characterization. Here, a detailed characterization of a new GBM cell line, namely AHOL1, was conducted in order to fully characterize its molecular composition based on its karyotype, copy number alteration (CNA), and transcriptome profiling, followed by the validation of key elements associated with GBM tumorigenesis. Large numbers of CNAs and differentially expressed genes (DEGs) were identified. CNAs were distributed throughout the genome, including gains at Xq11.1-q28, Xp22.33-p11.1, Xq21.1-q21.33, 4p15.1-p14, 8q23.2-q23.3 and losses at Yq11.21-q12, Yp11.31-p11.2, and 15q11.1-q11.2 positions. Nine druggable genes were identified, including HCRTR2, ETV1, PTPRD, PRKX, STS, RPS6KA6, ZFY, USP9Y, and KDM5D. By integrating DEGs and CNAs, we identified 57 overlapping genes enriched in fourteen pathways. Altered expression of several cancer-related candidates found in the DEGs-CNA dataset was confirmed by RT-qPCR. Taken together, this first comprehensive genomic and transcriptomic landscape of AHOL1 provides unique resources for further studies and identifies several druggable targets that may be useful for therapeutics and biologic and molecular investigation of GBM.


Assuntos
Glioblastoma , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Genoma , Genômica , Glioblastoma/genética , Histona Desmetilases , Humanos , Antígenos de Histocompatibilidade Menor , Transcriptoma
3.
Braz. j. med. biol. res ; 54(3): e9571, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1153526

RESUMO

Cancer cell lines are widely used as in vitro models of tumorigenesis, facilitating fundamental discoveries in cancer biology and translational medicine. Currently, there are few options for glioblastoma (GBM) treatment and limited in vitro models with accurate genomic and transcriptomic characterization. Here, a detailed characterization of a new GBM cell line, namely AHOL1, was conducted in order to fully characterize its molecular composition based on its karyotype, copy number alteration (CNA), and transcriptome profiling, followed by the validation of key elements associated with GBM tumorigenesis. Large numbers of CNAs and differentially expressed genes (DEGs) were identified. CNAs were distributed throughout the genome, including gains at Xq11.1-q28, Xp22.33-p11.1, Xq21.1-q21.33, 4p15.1-p14, 8q23.2-q23.3 and losses at Yq11.21-q12, Yp11.31-p11.2, and 15q11.1-q11.2 positions. Nine druggable genes were identified, including HCRTR2, ETV1, PTPRD, PRKX, STS, RPS6KA6, ZFY, USP9Y, and KDM5D. By integrating DEGs and CNAs, we identified 57 overlapping genes enriched in fourteen pathways. Altered expression of several cancer-related candidates found in the DEGs-CNA dataset was confirmed by RT-qPCR. Taken together, this first comprehensive genomic and transcriptomic landscape of AHOL1 provides unique resources for further studies and identifies several druggable targets that may be useful for therapeutics and biologic and molecular investigation of GBM.


Assuntos
Humanos , Glioblastoma/genética , Regulação Neoplásica da Expressão Gênica , Antígenos de Histocompatibilidade Menor , Genoma , Genômica , Linhagem Celular Tumoral , Histona Desmetilases , Transcriptoma
4.
Opt Express ; 28(24): 35833-35843, 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33379691

RESUMO

Multimode interference (MMI) devices are key components in modern integrated photonic circuits. Here, we present acoustically tuned optical switches on an (Al,Ga)As platform that enable robust, compact and fast response systems improving on recently demonstrated technology. The device consists of a 2 × 2 MMI device fine-tuned in its center region by a focused surface acoustic wave (SAW) beam working in the low GHz range. In this way, we can tune the refractive index profile over a narrow modulation region and thus control the optical switching behaviour via the applied SAW intensity. Direct tuning of the MMI device avoids losses and phase errors inherent to arrayed waveguide based switches, while also reducing the dimensions of the photonic circuit.

5.
Bull Soc Pathol Exot ; 112(1): 22-29, 2019.
Artigo em Francês | MEDLINE | ID: mdl-31225729

RESUMO

Despite the criticism and reservations made about him still nowadays, Louis Pasteur may be considered one of the most important scientists of the last two centuries in public health, even if the work of the numerous scientists who preceded him have largely contributed to the successes he obtained without following too much to the rules of deontology and ethics currently in force in the world of research and medicine. He has definitively put down, by his experiments, the "theory of spontaneous generation" in force since antiquity, validated that of "germs or microbes", enacted the first rules of asepsis, while inspiring those of the antisepsis applied by Joseph Lister, and developed a certain number of vaccinations in veterinary and human medicine, including the anti-rabies, the one which made him famous all over the world. All this was not done without difficulty and Pasteur encountered for a large part of his life the misunderstanding of his contemporaries and the hostility of the medical world to which he did not belong. The authors comment in this text the movie The Story of Louis Pasteur by William Dieterle, filmed in 1936, based on the knowledge acquired since that date and doing the part of the real and the fiction.


Malgré les critiques et les réserves dont il est l'objet aujourd'hui, Louis Pasteur peut être considéré comme l'un des scientifiques les plus importants de ces deux derniers siècles en matière de santé publique, même si les apports des nombreux hommes de science qui l'ont précédé ont largement contribué aux succès qu'il obtint sans trop se soucier des règles de déontologie et d'éthique actuellement en vigueur dans le monde de la recherche et de la médecine. Il a mis définitivement à bas, par ses expériences, la « théorie de la génération spontanée ¼ en vigueur depuis l'Antiquité, validé celle « des germes ou microbes ¼, édicté les premières règles de l'asepsie tout en inspirant celles de l'antisepsie appliquée par Joseph Lister et mit au point un certain nombre de vaccinations en médecine vétérinaire puis humaine, notamment celle contre la rage, ce qui le rendit célèbre dans le monde entier. Tout cela ne s'est pas fait sans difficulté, et Pasteur s'est heurté pendant une grande partie de sa vie à l'incompréhension de ses contemporains et à l'hostilité du monde médical auquel il n'appartenait pas. Les auteurs commentent dans ce texte le film L'Histoire de Louis Pasteur de William Dieterle, tourné en 1936, en s'appuyant sur les connaissances acquises depuis cette date et en faisant la part du réel et de l'imaginé.


Assuntos
Filmes Cinematográficos , História do Século XIX , História do Século XX , Filmes Cinematográficos/história , Vacina Antirrábica/história , Pesquisa/história , Vacinas/história
6.
J Appl Microbiol ; 124(1): 75-84, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29072357

RESUMO

AIMS: This study aims to improve characteristics of Piper regnellii extract to make it applicable in formulations to treat dermatophytosis, also known as ringworm. METHODS AND RESULTS: Microparticles (MPs) were produced by spray drying with gelatin, alginate and chitosan as encapsulating agents; characterized by scanning electron microscopy, encapsulation efficiency, thermal analyses and X-ray diffraction; and tested against Trichophyton rubrum by broth microdilution. Produced MPs had a mean diameter less than 2 µm, an increase in stability and release of the extract and good results for encapsulation efficiency, being 85·6% to gelatin MP, 71·3% to chitosan MP and 60·6% to alginate. MPs preserved the antifungal activity of P. regnellii extract T. rubrum. CONCLUSION: Microencapsulation provided a significant improvement in the stability of the P. regnellii extract and better solubilization of chemical compounds, maintaining the antifungal effect against T. rubrum. SIGNIFICANCE AND IMPACT OF THE STUDY: These results are useful for developing a formulation to treat fungal infections caused by dermatophyte species.


Assuntos
Piper/química , Extratos Vegetais/farmacologia , Trichophyton/efeitos dos fármacos , Antifúngicos/farmacologia , Biopolímeros/farmacologia , Cromatografia Líquida de Alta Pressão , Microscopia Eletrônica de Varredura , Difração de Raios X
7.
Nanotechnology ; 28(29): 295702, 2017 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-28574403

RESUMO

InAs nanowires grown by vapor-liquid-solid (VLS) method are investigated by photoluminescence. We observe that the Fermi energy of all samples is reduced by ∼20 meV when the size of the Au nanoparticle used for catalysis is increased from 5 to 20 nm. Additional capping with a thin InP shell enhances the optical emission and does not affect the Fermi energy. The unexpected behavior of the Fermi energy is attributed to the differences in the residual donor (likely carbon) incorporation in the axial (low) and lateral (high incorporation) growth in the VLS and vapor-solid (VS) methods, respectively. The different impurity incorporation rate in these two regions leads to a core/shell InAs homostructure. In this case, the minority carriers (holes) diffuse to the core due to the built-in electric field created by the radial impurity distribution. As a result, the optical emission is dominated by the core region rather than by the more heavily doped InAs shell. Thus, the photoluminescence spectra and the Fermi energy become sensitive to the core diameter. These results are corroborated by a theoretical model using a self-consistent method to calculate the radial carrier distribution and Fermi energy for distinct diameters of Au nanoparticles.

8.
Artigo em Inglês | MEDLINE | ID: mdl-28134462

RESUMO

Genitourinary cancers are significant causes of morbidity and mortality around the world. The present review summarises the current literature on suicide and its risk factors among patients with genitourinary cancers. The review was based on relevant articles published in MEDLINE, ProQuest, PsycINFO, Science Direct and Scopus databases. Patients with prostate cancer represented the most important risk group for suicide, among patients with urogenital cancers. Other risk factors are male gender, older age, white race, advanced disease, living alone and co-existing psychological comorbidities. Findings from the review call for a greater caregiver awareness on psychosocial morbidity and suicidality among genitourinary cancer patients pre- and post-treatment and their early identification, adoption of risk-reduction strategies and prompt referral for expert mental health care.


Assuntos
Suicídio , Neoplasias Urogenitais/psicologia , Fatores Etários , Efeitos Psicossociais da Doença , Humanos , Transtornos Mentais/complicações , Fatores de Risco , Fatores Sexuais , Apoio Social , Fatores Socioeconômicos , Suicídio/psicologia , Suicídio/estatística & dados numéricos
9.
Zootaxa ; 4020(1): 1-50, 2015 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-26624088

RESUMO

In the present work, based on material from distinct mountain ranges in Brazil, 11 new species of Cloeodes with hind wings or hind wing pads are described, illustrated and discussed. Among the new species, in C. aiuruoca, C. amantykyra, C. atlanticus, C. boldrinii and C. ioachimi, the apex of the fore femora in the nymphs is extremely projected (a characteristic previously found only in two species of the genus). Cloeodes guara and C. tracheatus share the presence of unusual large and dark gills. Cloeodes melanotarsus is readily distinguished by conspicuous blackish tarsi, C. lucifer by the bright yellow coloration of tergum I, and C. xyrognathos by blade-like incisors. Cloeodes magnus, besides being the largest species of the genus, with a body size reaching 12 mm, possess short maxillary palp. Comments on the presence of C. irvingi and C. opacus in Brazil are also provided. An interactive online key is provided for the nymphs of all the species of Cloeodes in which hind wing pads are present.


Assuntos
Ephemeroptera/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Brasil , Ecossistema , Ephemeroptera/anatomia & histologia , Ephemeroptera/crescimento & desenvolvimento , Feminino , Masculino , Tamanho do Órgão
10.
Opt Express ; 23(16): 21213-31, 2015 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-26367971

RESUMO

We demonstrate compact tunable phased-array wavelength-division multiplexers driven by surface acoustic waves (SAWs) in the low GHz range. The devices comprise two couplers, which respectively split and combine the optical signal, linked by an array of single-mode waveguides (WGs). Two different layouts are presented, in which multi-mode interference couplers or free propagating regions were separately employed as couplers. The multiplexers operate on five equally distributed wavelength channels, with a spectral separation of 2 nm. A standing SAW modulates the refractive index of the arrayed WGs. Each wavelength component periodically switches paths between the output channel previously asigned by the design and the adjacent channels, at a fixed applied acoustic power. The devices were monolithically fabricated on (Al,Ga)As. A good agreement between theory and experiment is achieved.

11.
Neuroscience ; 300: 246-53, 2015 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-25999296

RESUMO

Depression is one of the most common psychiatric symptoms in patients with Parkinson's disease (PD). Some authors have reported that depression is characterized by activation of the inflammatory response. Animal models of PD also present with depressive-like behavior, such as increased immobility time in the modified forced swim test and anhedonia-like behavior in the sucrose preference test. Considering the potential neuroprotective effect of nonsteroidal antiinflammatory drugs in neurodegenerative diseases, the objective of the present study was to investigate the effects of piroxicam on depressive-like behavior in male Wistar rats lesioned with 6-hydroxydopamine (6-OHDA) in the substantia nigra (SN). Antidepressant-like effects were observed after prolonged administration of piroxicam for 21days. In the forced swim test, the 6-OHDA+saline group exhibited significant reductions in swimming time and increased immobility time compared with the sham+saline. In the sucrose preference test, the 6-OHDA+piroxicam group exhibited no reduction of sucrose preference compared with the sham+saline, with significant effects of treatment and time and a significant treatment×time interaction. 5-Hydroxytryptamine (5-HT) levels significantly decreased in the hippocampus in the 6-OHDA+saline group and not changed in the 6-OHDA+piroxicam group when compared with the sham+saline on day 21. In conclusion, 21-day treatment with piroxicam reversed the onset of depressive-like behavior and prevented the reduction of hippocampal 5-HT levels.


Assuntos
Antidepressivos/farmacologia , Transtorno Depressivo/tratamento farmacológico , Transtorno Depressivo/fisiopatologia , Transtornos Parkinsonianos/fisiopatologia , Piroxicam/farmacologia , Anedonia/efeitos dos fármacos , Anedonia/fisiologia , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Transtorno Depressivo/patologia , Sacarose na Dieta , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Ácido Hidroxi-Indolacético/metabolismo , Masculino , Neurônios/efeitos dos fármacos , Neurônios/patologia , Oxidopamina , Transtornos Parkinsonianos/patologia , Transtornos Parkinsonianos/psicologia , Distribuição Aleatória , Ratos Wistar , Serotonina/metabolismo , Substância Negra/efeitos dos fármacos , Substância Negra/patologia , Natação/psicologia
12.
Obes Surg ; 25(1): 36-44, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25098565

RESUMO

BACKGROUND: This study aims to assess the clinical and physiological effects of Roux-en-Y gastric bypass (RYGBP) on type 2 diabetes associated with mild obesity (body mass index [BMI] 30-34.9 kg/m(2)) over 24 months postsurgery. METHODS: In this prospective trial, 36 mildly obese subjects (19 males) with type 2 diabetes using oral antidiabetic drugs with (n = 24) or without insulin (n = 12) underwent RYGBP. Follow-up was conducted at baseline and 3, 6, 12, and 24 months postsurgery. The following endpoints were considered: changes in HbA1c, fasting glucose and insulin, antidiabetic therapy, BMI, oral glucose insulin sensitivity [OGIS, from meal tolerance test (MTT)], beta-cell secretory function [ΔCP(0-30)/ΔGlu(0-30) (ΔC-peptide/Δglucose ratio, MTT 0-30 min), disposition index (DI = OGIS [Symbol: see text] ΔCP(0-30)/ΔGlu(0-30)], glucagon-like peptide (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) [incremental area under the curve (AUCi)], adiponectin, C-reactive protein, and lipids. RESULTS: All subjects achieved normal-to-overweight BMI after 3 months. Over 24 months, 31/36 (86 %) subjects presented HbA1c <7 % [complete and partial remission of diabetes in 9/36 (22 %) and 1/36 (3 %), respectively]. Since 3 months postsurgery, improvements were observed in OGIS [290 (174) to 373 (77) ml/min/m(2), P = 0.009], ΔCP(0-30)/ΔGlu(0-30) [0.24 (0.19) to 0.52 (0.34) ng/mg, P = 0.001], DI [7.16 (8.53) to 19.8 (15.4) (ng/mg) (ml/min/m(2)), P = 0.001], GLP-1 AUCi [0.56 (0.64) to 3.97 (3.86) ng/dl [Symbol: see text] 10 min [Symbol: see text] 103, P = 0.000], and GIP AUCi [30.2 (12.6) to 27.0 (20.2) ng/dl [Symbol: see text] 10 min [Symbol: see text] 103, P = 0.004]. At baseline and after 12 months, subjects with diabetes nonremission had longer diabetes duration, higher HbA1c, lower beta-cell secretory function, and higher first 30-min GIP AUCi, compared with those with remission. CONCLUSIONS: RYGBP improves the glucose metabolism in subjects with type 2 diabetes and mild obesity. This effect is associated with improvement of insulin sensitivity, beta-cell secretory function, and incretin secretion.


Assuntos
Diabetes Mellitus Tipo 2/cirurgia , Derivação Gástrica , Obesidade/cirurgia , Adulto , Glicemia/metabolismo , Índice de Massa Corporal , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Teste de Tolerância a Glucose , Humanos , Insulina/metabolismo , Resistência à Insulina/fisiologia , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Obesidade/metabolismo , Índice de Gravidade de Doença
13.
Opt Express ; 21(18): 21669-76, 2013 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-24104040

RESUMO

Photonic modulators are one of the most important elements of integrated photonics. We have designed, fabricated, and characterized a tunable photonic modulator consisting of two 180°-dephased output waveguide channels, driven by a surface acoustic wave in the GHz frequency range built on (Al,Ga)As. Odd multiples of the fundamental driven frequency are enabled by adjusting the applied acoustic power. A good agreement between theory and experimental results is achieved. The device can be used as a building block for more complex integrated functionalities and can be implemented in several material platforms.

14.
Med Vet Entomol ; 27(3): 247-54, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22985051

RESUMO

Triatoma brasiliensis (Hemiptera: Reduviidae) is an important vector of Chagas' disease in both sylvatic and peridomestic ecotopes. Discriminating between these populations of Triatominae has been proposed as a means of investigating re-infestation rates of human dwellings. Geometric morphometrics have been widely applied in the study of Triatominae polymorphisms at species and population levels. This study characterizes morphometric differences between sylvatic and peridomestic populations, as well as between sexes in T. brasiliensis specimens from Jaguaruana, Ceará, in northeastern Brazil. No differences in either the shape or size of the cephalic capsule were apparent between sexes or ecotopes. However, the wings showed differentiation in shape and size. Sexual dimorphism was detected, with females presenting significantly higher values and conformations. Size differentiation was also evident, with sylvatic specimens being generally larger than peridomestic examples. These results indicate that differences in the wings of T. brasiliensis may be related to the existence of phenotypic plasticity, and variations in size and shape may be associated with different ecotopes, possibly as a result of conditions in each micro-habitat, such as temperature, relative humidity, food supply and density.


Assuntos
Insetos Vetores/anatomia & histologia , Insetos Vetores/fisiologia , Triatoma/anatomia & histologia , Triatoma/fisiologia , Adaptação Fisiológica , Animais , Brasil , Doença de Chagas/epidemiologia , Doença de Chagas/parasitologia , Meio Ambiente , Feminino , Cabeça/anatomia & histologia , Insetos Vetores/genética , Masculino , Fenótipo , Análise de Componente Principal , Caracteres Sexuais , Triatoma/genética , Asas de Animais/anatomia & histologia
15.
Nanotechnology ; 23(37): 375704, 2012 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-22922756

RESUMO

Wurtzite InAs nanowire samples grown by chemical beam epitaxy have been analyzed by photoluminescence spectroscopy. The nanowires exhibit two main optical emission bands at low temperatures. They are attributed to the recombination of carriers in quantum well structures, formed by zincblende-wurtzite alternating layers, and to the donor-acceptor pair. The blue-shift observed in the former emission band when the excitation power is increased is in good agreement with the type-II band alignment between the wurtzite and zincblende sections predicted by previous theoretical works. When increasing the temperature and the excitation power successively, an additional band attributed to the band-to-band recombination from wurtzite InAs appears. We estimated a lower bound for the wurtzite band gap energy of approximately 0.46 eV at low temperature.

16.
Acta Trop ; 122(2): 196-204, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22314031

RESUMO

This paper documents the morphology of previously undescribed adult reproductive accessory glands in eight species of blood-feeding Hemiptera, vectors of Chagas disease. These species are three Triatoma (T. dimidiata, T. klugi, T. sordida), three Rhodnius (R. brethesi, R. nasutus, R. pictipes), and one species each from Nesotriatoma (N. bruneri) and Panstrongylus (P. megistus). This survey shows that the male reproductive systems between species of four genera of Reduviidae adhere to the same general plan seen in previously described vectors of Chagas disease. This morphological similarity suggests that reproductive success of the male is contingent on the delivery of a vital set of male accessory gland secretions to the female in conjunction with material from the testes and seminal vesicle. However, variations were observed in the accessory glands of females, especially at the level of the genus. The spermathecae are morphologically distinct, and the posterior accessory glands are absent in some. The differences in spermathecae morphology likely reflect physiological adaptations associated with speciation driven by cryptic female choice in which the female determines which sperm are used for fertilization. Differences in the posterior reproductive accessory gland can be correlated with variations in ovipositioning behaviour. Since reproductive physiology is important for species success, this information also augments epidemiological studies by providing a comparison to R. prolixus, a Chagas disease vector for which the physiology is well known.


Assuntos
Doença de Chagas/transmissão , Insetos Vetores/anatomia & histologia , Reduviidae/anatomia & histologia , Animais , Feminino , Genitália/anatomia & histologia , Masculino , Reprodução
17.
Nano Lett ; 12(1): 252-8, 2012 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-22142481

RESUMO

The oscillating piezoelectric field of a surface acoustic wave (SAW) is employed to transport photoexcited carriers, as well as to spatially control exciton recombination in GaAs-based nanowires (NWs) on a subns time scale. The experiments are carried out in core-shell NWs transferred to a SAW delay line on a LiNbO(3) crystal. Carriers generated in the NW by a focused laser spot are acoustically transferred to a second location, leading to the remote emission of subns light pulses synchronized with the SAW phase. The dynamics of the carrier transport, investigated using spatially and time-resolved photoluminescence, is well-reproduced by computer simulations. The high-frequency contactless manipulation of carriers by SAWs opens new perspectives for applications of NWs in opto-electronic devices operating at gigahertz frequencies. The potential of this approach is demonstrated by the realization of a high-frequency source of antibunched photons based on the acoustic transport of electrons and holes in (In,Ga)As NWs.


Assuntos
Arsenicais/química , Arsenicais/efeitos da radiação , Cristalização/métodos , Gálio/química , Gálio/efeitos da radiação , Nanoestruturas/química , Nanoestruturas/efeitos da radiação , Sonicação , Substâncias Macromoleculares/química , Substâncias Macromoleculares/efeitos da radiação , Teste de Materiais , Conformação Molecular/efeitos da radiação , Nanoestruturas/ultraestrutura , Tamanho da Partícula , Fótons , Propriedades de Superfície/efeitos da radiação
18.
Int J Obes (Lond) ; 36(3): 363-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21894159

RESUMO

AIMS/HYPOTHESIS: Bariatric surgery is currently employed as an effective approach to treat class III obesity and class II obesity with co-morbidities. Unfortunately, the general anthropometric and metabolic outcomes of the surgery are not homogeneous, and defining the eligibility criteria that allow for a more precise prediction of the outcomes of this invasive procedure will refine the selection of patients. Here we tested the hypothesis that the Gly482Ser polymorphism of the ppargc1a gene would predict different outcomes following bariatric surgery. METHODS: Fifty-five patients (26 Gly/Gly and 29 Gly/Ser+Ser/Ser) selected for the Roux-en-Y gastric bypass according to the National Institutes of Health Consensus Statement criteria were followed up for 1 year, monitoring their anthropometric, metabolic and inflammatory parameters. RESULTS: Patients with the Gly482Ser polymorphism had significantly improved reductions in the waist/hip ratio, fasting blood glucose, C-reactive protein, blood leukocyte count, serum interleukin-6 and intima-media thickness of the carotid artery, as compared with Gly/Gly patients. CONCLUSIONS/INTERPRETATION: Thus, the Gly482Ser polymorphism may predict a more favorable metabolic and inflammatory outcome for obese patients submitted to bariatric surgery, leading to a reduced atherosclerotic risk.


Assuntos
Doença da Artéria Coronariana/prevenção & controle , Derivação Gástrica , Obesidade Mórbida/genética , Obesidade Mórbida/cirurgia , Polimorfismo de Nucleotídeo Único , Adolescente , Adulto , Brasil/epidemiologia , Proteína C-Reativa/genética , Espessura Intima-Media Carotídea , Comorbidade , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/genética , Doença da Artéria Coronariana/patologia , Feminino , Derivação Gástrica/métodos , Glicina , Humanos , Interleucina-6/genética , Masculino , Pessoa de Meia-Idade , Obesidade Mórbida/epidemiologia , Reação em Cadeia da Polimerase , Serina , Resultado do Tratamento , Redução de Peso , Adulto Jovem
19.
Nanotechnology ; 22(6): 065703, 2011 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-21212489

RESUMO

We performed a detailed investigation of the structural and optical properties of multi-layers of InP/GaAs quantum dots, which present a type II interface arrangement. Transmission electronic microscopy analysis has revealed relatively large dots that coalesce forming so-called quantum posts when the GaAs layer between the InP layers is thin. We observed that the structural properties and morphology affect the resulting radiative lifetime of the carriers in our systems. The carrier lifetimes are relatively long, as expected for type II systems, as compared to those observed for single layer InP/GaAs quantum dots. The interface intermixing effect has been pointed out as a limiting factor for obtaining an effective spatial separation of electrons and holes in the case of single layer InP/GaAs quantum-dot samples. In the present case this effect seems to be less critical due to the particular carrier wavefunction distribution along the structures.

20.
Phys Rev Lett ; 104(16): 165502, 2010 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-20482064

RESUMO

We present the experimental observation of Bloch oscillations, the Wannier-Stark ladder, and Landau-Zener tunneling of surface acoustic waves in perturbed grating structures on a solid substrate. A model providing a quantitative description of our experimental observations, including multiple Landau-Zener transitions of the anticrossed surface acoustic Wannier-Stark states, is developed. The use of a planar geometry for the realization of the Bloch oscillations and Landau-Zener tunneling allows a direct access to the elastic field distribution. The vertical surface displacement has been measured by interferometry.

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