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2.
J Food Sci ; 88(2): 757-771, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36633002

RESUMO

Ambelania acida is native to the Amazon region, with few published studies of its fruits. We examined the proximate composition of its fruits, including minerals, fatty acids, volatile organic compounds (VOCs), as well as its antioxidant capacity. The protein contents (2.61%) of the pulp and seeds (13.6%) were higher than observed in other taxa of the family or in other tropical fruits. Peel and pulp showed high contents of potassium, calcium, and magnesium, and the potassium content in the pulp was 1125 mg/100 g. The peel had higher contents of total phenolics, tannins, and ortho-diphenols than the pulp, as well as better antioxidant activity as evidenced by 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 1,1-diphenyl-2-picrylhydrazyl (DPPH), Ferric Reducing Antioxidant Power (FRAP), and Fe2+ chelating activity assays. GC-MS analyses identified 42 VOCs in the peel and pulp, with more than 90% being classified as terpenes. Eleven types of fatty acids were identified in the lipid fractions of the peel, pulp, and seeds. Linoleic acid, an essential fatty acid for humans, was the principal fatty acid in the edible portion of the fruit, therefore, evidencing its nutritionally significant profile for the fruits when considering the relationship among polyunsaturated, saturated, and monounsaturated fatty acids. The information gathered here indicates that this native fruit is a healthy food source and its cultivation and consumption should be stimulated.


Assuntos
Antioxidantes , Frutas , Humanos , Frutas/química , Antioxidantes/química , Minerais/análise , Potássio , Ácido Linoleico/análise
3.
Med Oral Patol Oral Cir Bucal ; 27(4): e301-e309, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35717622

RESUMO

BACKGROUND: Analysis of the tumor microenvironment has been proposed as a strategy for the treatment and prognosis of different neoplastic processes. A grading system based on the tumor-stroma ratio (TSR), which evaluates the proportion of stroma in relation to neoplastic parenchyma at the invasion front, has shown a strong prognostic value in different neoplastic processes. The aim of the present systematic review was to understand the role of the TSR in head and neck squamous cell carcinoma (HNSCC), evaluating its correlation with clinical and prognostic parameters. MATERIAL AND METHODS: An electronic search was performed in PubMed/Medline, Web of Science, Science Direct, Scopus, Embase, and the Cochrane Collaboration Library. Publications assessing the relationship between TSR and prognosis in cases of HNSCC were eligible. The quality of the studies was assessed independently by four evaluators using the Newcastle-Ottawa scale. RESULTS: After application of the previously es+lished inclusion/exclusion criteria, nine articles were included in the qualitative synthesis. With regards to quality on the Newcastle-Ottawa scale, an overall value of 4.55 was obtained. This systematic review demonstrated a strong association between TSR and prognosis in esophageal and oral squamous cell carcinomas. CONCLUSIONS: Histopathological analysis of the TSR can optimize the analysis of the prognosis of cases diagnosed with HNSSC. In addition, the TSR is a reliable and simple parameter that can be evaluated in hematoxylin/eosin-stained slides during routine laboratory examinations, showing high inter- and intraobserver agreement.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Carcinoma de Células Escamosas/patologia , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Células Estromais/patologia , Microambiente Tumoral
4.
Opt Lett ; 44(21): 5286-5289, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31674989

RESUMO

For some infrastructures such as oil and gas extraction boreholes or radioactive waste repositories, where distributed optical fiber sensors are employed to grant the safety of the facilities, the presence of gas species such as hydrogen or deuterium is one of the most relevant parameters to monitor. The possibility of employing the same kind of sensors for this purpose is of special interest, reducing the cost by employing a single interrogator, able to measure multiple parameters by simply employing adequate sensing fibers. To meet this goal, we present here a chemical sensor based on chirped-pulse phase-sensitive optical time-domain reflectometry (CP-φOTDR), which is able to detect these species while they diffuse into the silica fiber. The ability of chirped-pulse φOTDR to measure a change in refractive index with sensitivity around 10-8 has allowed determining hydrogen concentration with accuracy on the order of 10-3 mol/m3 and spatial resolution ∼6 m. Another experiment provides an indirect measurement of the solubility of deuterium in a standard telecom-grade optical fiber, which is found to be around 1.47×1024 m3/bar.

5.
Colloids Surf B Biointerfaces ; 177: 94-104, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30711763

RESUMO

Due to the its physical-chemical properties, alumina nanoparticles have potential applications in several areas, such as nanobiomaterials for medicinal or orthodontic implants, although the introduction of these devices poses a serious risk of microbial infection. One convenient strategy to circumvent this problem is to associate the nanomaterials to antimicrobial peptides with broad-spectrum of activities. In this study we present two novel synthesis approaches to obtain fibrous type alumina nanoparticles covalently bound to antimicrobial peptides. In the first strategy, thiol functionalized alumina nanoparticles were linked via disulfide bond formation to a cysteine residue of an analog of the peptide BP100 containing a four amino acid spacer (Cys-Ala-Ala-Ala). In the second strategy, alumina nanoparticles were functionalized with azide groups and then bound to alkyne-decorated analogs of the peptides BP100 and DD K through a triazole linkage obtained via a copper(I)-catalyzed cycloaddition reaction. The complete physical-chemical characterization of the intermediates and final materials is presented along with in vitro biological assays and membrane interaction studies, which confirmed the activity of the obtained nanobiostructures against both bacteria and fungi. To our knowledge, this is the first report of aluminum nanoparticles covalently bound to triazole-peptides and to a disulfide bound antimicrobial peptide with high potential for biotechnological applications.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Antifúngicos/síntese química , Antifúngicos/farmacologia , Dissulfetos/farmacologia , Nanopartículas/química , Peptídeos/farmacologia , Triazóis/farmacologia , Óxido de Alumínio/química , Óxido de Alumínio/farmacologia , Antibacterianos/química , Antifúngicos/química , Candida/efeitos dos fármacos , Dissulfetos/química , Escherichia coli/efeitos dos fármacos , Fusarium/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Tamanho da Partícula , Peptídeos/síntese química , Peptídeos/química , Propriedades de Superfície , Triazóis/química
6.
Reprod Domest Anim ; 53(3): 617-623, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29431233

RESUMO

During cryopreservation, sperm was submitted to an increase in reactive oxygen species generation. This work aimed to improve the quality of frozen equine sperm after the addition of antioxidants lactoferrin (Lf) and catalase (Cat) to a freezing extender. Semen from six stallions was frozen with the extenders: F1) control, INRA 82 freezing extender, F2) F1 + 500 µg/ml Lf and F3) F1 + 200 IU/ml Cat. After thawing, sperm motility parameters, membrane functionality and integrity, and acrosome integrity and spontaneous acrosome-reacted sperm were evaluated with a computer-assisted sperm analysis, a hypoosmotic swelling test and epifluorescent microscopy, respectively. Nitrite, hydroperoxide and iron concentrations of frozen semen were measured with spectrophotometry. The percentage of functional membrane sperm treated with Lf was higher (50.7% ± 11.6%) compared to that of the control (37.6% ± 15.6%), while the iron (61.4 ± 11.6 vs 73.3 ± 13.8 mg/dl) and nitrite concentrations (16.3 ± 7.1 vs 25.9 ± 4.2 µM/µg protein) were lower, respectively (p < .05). Thus, it can be suggested that Lf protect stallion spermatozoon during freezing as it has increased the percentage of sperm with functional membrane and decreased the lipid oxidant agents.


Assuntos
Criopreservação/veterinária , Crioprotetores/farmacologia , Cavalos , Lactoferrina/farmacologia , Espermatozoides/efeitos dos fármacos , Reação Acrossômica , Animais , Antioxidantes , Catalase/farmacologia , Membrana Celular/fisiologia , Criopreservação/métodos , Masculino , Análise do Sêmen/veterinária , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides , Espermatozoides/citologia
7.
Colloids Surf B Biointerfaces ; 163: 275-283, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29329073

RESUMO

The functionalization of alumina nanoparticles of specific morphology with antimicrobial peptides (AMP) can be a promising strategy for modeling medical devices and packaging materials for cosmetics, medicines or food, since the contamination by pathogens could be reduced. In this paper, we show the synthesis of a fibrous-like alumina nanobiostructure, as well as its functionalization with the peptide EAAA-BP100, an analog of the antimicrobial peptide BP100. The antibacterial activity of the obtained material against some bacterial strains is also investigated. The covalent binding of the peptide to the nanoparticles was promoted by a reaction between the carboxyl group of the glutamate side chain (E1) of the peptide and the amino groups of the alumina nanoparticles, previously modified by reaction with 3-aminopropyltrietoxysilane (APTES). The functionalized nanoparticles were characterized by zeta potential measurements, Fourier transform infrared spectroscopy, and other physicochemical techniques. Although the obtained alumina nanobiostructure shows a relatively low degree of substitution with EAAA-BP100, antibacterial activities against Escherichia coli and Salmonella typhimurium strains are appreciably higher than the activities of the free peptide. The obtained results can affect the design of new hybrid nanobiomaterials based on nanoparticles functionalized with AMP.


Assuntos
Óxido de Alumínio/química , Nanoestruturas/química , Oligopeptídeos/química , Oligopeptídeos/síntese química , Sequência de Aminoácidos , Antibacterianos/química , Antibacterianos/farmacologia , Fluoresceínas/química , Testes de Sensibilidade Microbiana , Nanoestruturas/ultraestrutura , Oligopeptídeos/farmacologia , Propilaminas/química , Silanos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Temperatura , Difração de Raios X
8.
Cryo Letters ; 39(5): 298-305, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30963161

RESUMO

BACKGROUND: Frozen equine semen has lower fertility compared to cooled semen. Due to the difficulty to obtain equine oocytes, a heterologous zona pellucida binding assay (ZBA) is an alternative method to predict the fertilizing capability of equine frozen sperm. The rate of capacitated and hyperactivated sperm according to their motility characteristics were analyzed with a Computer Assisted Sperm Analyzer. We believe this report describes for the first time the in vitro hyperactivation induction and the heterologous ZBA to predict the fertilizing ability of frozen equine sperm. OBJECTIVE: This work aimed at developing an assay to evaluate the fertilizing ability of frozen equine sperm using a bovine ZBA with the use of an in vitro capacitation and hyperactivation media with procaine and calcium ionophore A23187, respectively. MATERIALS AND METHODS: The sperm motility characteristics, intact and acrosome reacted sperm rates, and number of stallion sperm bound to the bovine ZP were calculated. RESULTS: The procaine group showed a hyperactivation motility pattern, although it improved ZP sperm binding similarly to the capacitation group. CONCLUSION: The capacitation medium improved the IVF capability of frozen equine sperm, allowing the highest possibility of sperm-oocyte interaction.


Assuntos
Criopreservação , Fertilização , Espermatozoides/fisiologia , Zona Pelúcida , Animais , Bovinos , Cavalos , Masculino , Motilidade dos Espermatozoides , Interações Espermatozoide-Óvulo
9.
Eur J Neurol ; 25(1): 171-177, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29053913

RESUMO

BACKGROUND AND PURPOSE: Morphological changes of the internal carotid arteries (McICA) are frequently found during cervical ultrasound studies. However, the etiology of McICA remains controversial. During this study, the prevalence and demographic characteristics of McICA, such as kinking, coiling or looping identified by Doppler ultrasound, were analysed and its relationship with vascular risk factors and stroke was assessed. METHODS: A retrospective study was performed by analysing 19 804 patients who were subjected to cervical ultrasonographic study between January 2000 and June 2012. The data were statistically analysed with SPSS® 20 and a multivariate logistic regression was performed. Statistical significance was accepted for P < 0.05 and 95% confidence intervals (CIs) were used. RESULTS: Morphological changes of the internal carotid arteries were present in 2678 patients (13.5%) and were unilateral in 61.6% of these cases. Carotid kinking was found in 80% of the patients, coiling in 16% and looping in 1%. In multivariate analysis, the presence of McICA was related to older groups (1.04; 95% CI, 1.04-1.05; P < 0.01), female gender (1.78; 95% CI, 1.64-1.94; P < 0.01), patients with hyperlipidemia (1.28; 95% CI, 1.17-1.40; P < 0.01), carotid thickness (1.22; 95% CI, 1.13-1.33; P < 0.01) and cardiac or cardioembolic disease (1.11; 95% CI, 1.01-1.21; P = 0.02). The results of this study indicate that kinking in the carotid artery was associated with ipsilateral cerebral ischemic events (1.43; 95% CI, 1.040-1.958; P < 0.05). CONCLUSION: Morphological changes of the internal carotid arteries were associated with aging, female gender and patients with hyperlipidemia, hypertension, diabetes and heart disease. Kinking was associated with ipsilateral cerebral ischemia.


Assuntos
Artéria Carótida Interna/diagnóstico por imagem , Artéria Carótida Interna/crescimento & desenvolvimento , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Isquemia Encefálica/diagnóstico por imagem , Artéria Carótida Interna/anatomia & histologia , Espessura Intima-Media Carotídea , Complicações do Diabetes/epidemiologia , Feminino , Cardiopatias/epidemiologia , Humanos , Hiperlipidemias/complicações , Hipertensão/complicações , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Caracteres Sexuais , Ultrassonografia
10.
J Phys Condens Matter ; 29(29): 295501, 2017 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-28561012

RESUMO

We report here the O K-edge x-ray absorption spectra of hexagonal and orthorhombic YMnO3 thin films, aiming at comparing the changes in the Mn 3d bands as well as the role of Y 4d-O 2p hybridization. The experimental results were analyzed using first principles (GGA) band structure calculations. The spectra present clear differences in the Mn 3d bands, which are attributed to changes in the Mn-O coordination and symmetry. A strong Y 4d-O 2p hybridization is observed in both the hexagonal and orthorhombic films, and its possible role on the occurrence of the observed ferroelectricity is discussed.

11.
Eur J Neurol ; 24(7): 929-934, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28497610

RESUMO

BACKGROUND AND PURPOSE: Although cerebrovascular disorders are the main cause of epilepsia partialis continua (EPC) in adulthood, the frequency of EPC after stroke is unknown. The aim was to prospectively ascertain its frequency 1 year after an ischaemic stroke. METHODS: This was a prospective study of consecutive acute anterior circulation ischaemic stroke patients, previously independent, with an admission National Institutes of Health Stroke Scale score ≥4, an acute ischaemic lesion on imaging and no previous epileptic seizures. During admission patients received standardized diagnostic and medical care and were submitted to a neurophysiological evaluation protocol. One year after stroke, patients were re-evaluated by an epilepsy expert neurologist and performed a video-electroencephalogram with electromyography co-registration whenever myoclonus was observed during neurological examination for jerk-locked back averaging analysis (JLBA). EPC was defined as continuously repeated fragments of epileptic seizures, with preserved consciousness, lasting at least 1 h, and representing locally restricted epileptic activity. RESULTS: In all, 151 acute anterior circulation stroke patients were consecutively included and prospectively evaluated, but 23 died in the first year. One year after stroke, from 127 patients alive, 117 (92.1%) underwent clinical and neurophysiological evaluation. In two (1.7%) patients, EPC diagnosis was made both by clinical and electroencephalographic criteria, namely JLBA. Both patients had a history of remote symptomatic seizures and one of them acute symptomatic seizures and non-convulsive status epilepticus criteria during the first 7 days after stroke. CONCLUSIONS: Despite its low frequency, the high stroke incidence makes post-stroke EPC relevant. This study draws attention to this recognizable condition with therapeutic and eventually prognostic implications.


Assuntos
Isquemia Encefálica/complicações , Epilepsia Parcial Contínua/etiologia , Acidente Vascular Cerebral/complicações , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/epidemiologia , Artérias Cerebrais/diagnóstico por imagem , Circulação Cerebrovascular , Eletroencefalografia , Eletromiografia , Epilepsia Parcial Contínua/diagnóstico por imagem , Epilepsia Parcial Contínua/epidemiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Neuroimagem , Exame Neurológico , Prognóstico , Estudos Prospectivos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/epidemiologia
12.
Eur J Neurol ; 24(6): 755-761, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28418189

RESUMO

BACKGROUND AND PURPOSE: Intravenous alteplase (rtPA) may be associated with seizures and epileptic activity in the electroencephalogram (EEG). The aim of this work was to compare the frequency of seizures and EEG abnormalities between stroke patients treated and not treated with rtPA. METHODS: This was a prospective study of consecutive acute anterior circulation ischaemic stroke patients, with 1-year follow-up. Patients were previously independent, had an admission National Institute of Health Stroke Scale score ≥4, an acute ischaemic lesion and no previous seizures. They received standardized diagnostic and medical care. A video-EEG was performed in 72 h (first EEG); during admission (daily until day 7 and after that if neurological worsening); at discharge and 1 year after stroke. RESULTS: In all, 151 patients (101 treated with rtPA) were included. The frequency of acute and remote symptomatic seizures was not significantly different between rtPA treated and non-treated patients (P = 0.726 and P = 0.748, respectively). Clinical paroxysmal phenomena during rtPA perfusion were observed in five (5%) patients. In the first EEG, rtPA treated patients more often had background diffuse slowing (43.6% vs. 26.0%, P = 0.036). This difference was no longer observed at discharge (24.0% vs. 19.1%, P = 0.517) nor 1 year after (11.8% vs. 10.0%, P = 0.765). No differences were found in the frequency of epileptiform (P = 0.867) or periodic discharges (P = 0.381). CONCLUSIONS: Intravenous alteplase is not associated with an increased risk of clinical or electroencephalographic epileptic phenomena.


Assuntos
Epilepsia/induzido quimicamente , Fibrinolíticos/efeitos adversos , Convulsões/induzido quimicamente , Acidente Vascular Cerebral/tratamento farmacológico , Ativador de Plasminogênio Tecidual/efeitos adversos , Administração Intravenosa , Idoso , Eletroencefalografia , Feminino , Fibrinolíticos/administração & dosagem , Fibrinolíticos/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Ativador de Plasminogênio Tecidual/administração & dosagem , Ativador de Plasminogênio Tecidual/uso terapêutico , Resultado do Tratamento
13.
Environ Res ; 155: 321-334, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28264781

RESUMO

Climate change and the growth of urban populations are two of the main challenges facing Europe today. These issues are linked as climate change results in serious challenges for cities. Recent attention has focused on how urban surface-atmosphere exchanges of heat and water will be affected by climate change and the implications for urban planning and sustainability. In this study energy fluxes for Greater Porto area, Portugal, were estimated and the influence of the projected climate change evaluated. To accomplish this, the Weather Research and Forecasting Model (WRF) and the Surface Urban Energy and Water Balance Scheme (SUEWS) were applied for two climatological scenarios: a present (or reference, 1986-2005) scenario and a future scenario (2046-2065), in this case the Representative Concentration Pathway RCP8.5, which reflects the worst set of expectations (with the most onerous impacts). The results show that for the future climate conditions, the incoming shortwave radiation will increase by around 10%, the sensible heat flux around 40% and the net storage heat flux around 35%. In contrast, the latent heat flux will decrease about 20%. The changes in the magnitude of the different fluxes result in an increase of the net all-wave radiation by 15%. The implications of the changes of the energy balance on the meteorological variables are discussed, particularly in terms of temperature and precipitation.


Assuntos
Mudança Climática , Modelos Teóricos , Cidades , Ecossistema , Previsões , Portugal , Tempo (Meteorologia)
14.
J Sports Med Phys Fitness ; 57(4): 490 - 495, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-26684439

RESUMO

AIM: to determine the effects of 28 days of inactivity on neuromuscular performance of elite women pole-vaulters. METHODS: Four athletes undertook measurements of rate of force development (RFD), unloaded and loaded vertical jump tests, drop jumps and a 45 m sprint test before and after a transition period of planned inactivity. RESULTS: The RFD and the ability to accelerate over very short distances (5 m) while sprinting improved after training cessation. Acceleration over longer distances (5-45 m) was impaired, while unloaded and loaded vertical jump tests suffered trivial to small changes. CONCLUSIONS: Therefore, we conclude that detraining periods of approximately one month or even longer may be implemented in elite pole-vaulters without significantly impairing performance. In addition, given that some neuromechanical capacities are enhanced after training reduction, our results can help coaches to implement tapering strategies in order to induce neuromuscular improvements and/or to achieve peak performance.

15.
Contemp Clin Trials Commun ; 5: 153-159, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29740631

RESUMO

The nature and the purpose of the ECRIN Data Centre Certification Programme are summarised, and a very brief description is given of the underlying standards (129 in total, divided into 19 separate lists). The certification activity performed so far is described. In a pilot phase 2 centres were certified in 2012. Calls in 2014 and 2015 resulted in a further 8 certified centres, with 2 certifications still in progress, and the 2016 call has generated several additional applications. The impact and benefits of the programme are listed, divided into a) the effects of the introduction of the standards, b) the effects of the certification programme in general, and c) the effects of the certification programme on individual units. The discussion emphasises the generally positive impact of the programme so far but stresses the need to better clarify the perspective and role of the programme.

16.
Andrologia ; 48(9): 862-868, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27739145

RESUMO

Cooled semen has been used routinely to prolong sperm viability until artificial insemination time. However, spermatozoa are subjected to oxidative stress. The aim of the present work was to investigate the protective and antioxidant effect of the milk proteins lactoferrin (Lf) and caseinate added to equine semen cooling extenders. Semen from six stallions was cooled at 5 °C after resuspension with C1) milk- and glucose-based, C2) 0.6% caseinate, C3) C2 + Lf 200 µg ml-1 , C4) C2 + Lf 500 µg ml-1 and C5) C2 + Lf 1000 µg ml-1 extenders, and kept at 5 °C for 24 h. Sperm motility characteristics and intact membrane rates were not different among the treatments (P > 0.05). As a result of the cooling process, the nitrite concentration increased significantly in the cooled semen (69.6 ± 78.9 µm per ×106 spermatozoa) compared with the fresh semen (8.6 ± 1.9 µm per ×106 spermatozoa). In contrast, the H2 O2 concentrations were lower in the 0.6% caseinate extender (265.9 ± 221.3 µm per ×106 spermatozoa) than in the milk extender (430.9 ± 199.8 µm per ×106 spermatozoa, P < 0.05), showing an antioxidative effect of the caseinate compared with the milk. However, in all groups, hydrogen peroxide concentrations were similar to the undiluted fresh semen (332.8 ± 151.3 µm per ×106 spermatozoa). Caseinate showed to be as efficient as milk to protect equine-cooled spermatozoon.


Assuntos
Antioxidantes , Cavalos , Preservação do Sêmen/veterinária , Animais , Caseínas , Membrana Celular/metabolismo , Temperatura Baixa , Peróxido de Hidrogênio/metabolismo , Inseminação Artificial/métodos , Inseminação Artificial/veterinária , Lactoferrina , Masculino , Leite , Nitritos/metabolismo , Sêmen/metabolismo , Preservação do Sêmen/métodos , Motilidade dos Espermatozoides , Espermatozoides/fisiologia
17.
Opt Express ; 24(19): 22303-18, 2016 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-27661964

RESUMO

A major cause of faults in optical communication links is related to unintentional third party intrusions (normally related to civil/agricultural works) causing fiber breaks or cable damage. These intrusions could be anticipated and avoided by monitoring the dynamic strain recorded along the cable. In this work, a novel technique is proposed to implement real-time distributed strain sensing in parallel with an operating optical communication channel. The technique relies on monitoring the Rayleigh backscattered light from optical communication data transmitted using standard modulation formats. The system is treated as a phase-sensitive OTDR (ΦOTDR) using random and non-periodical non-return-to-zero (NRZ) phase-shift keying (PSK) pulse coding. An I/Q detection unit allows for a full (amplitude, phase and polarization) characterization of the backscattered optical signal, thus achieving a fully linear system in terms of ΦOTDR trace coding/decoding. The technique can be used with different modulation formats, and operation using 4 Gbaud single-polarization dual PSK and 4 Gbaud dual-polarization quadrature PSK is demonstrated. As a proof of concept, distributed sensing of dynamic strain with a sampling of 125 kHz and a spatial resolution of 2.5 cm (set by the bit size) over 500 m is demonstrated for applied sinusoidal strain signals of 500 Hz. The limitations and possibilities for improvement of the technique are also discussed.

18.
Opt Express ; 24(12): 13121-33, 2016 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-27410330

RESUMO

So far, the optical pulses used in phase-sensitive OTDR (ΦOTDR) were typically engineered so as to have a constant phase along the pulse. In this work, it is demonstrated that by acting on the phase profile of the optical pulses, it is possible to introduce important conceptual and practical changes to the traditional ΦOTDR operation, thus opening a door for new possibilities which are yet to be explored. Using a ΦOTDR with linearly chirped pulses and direct detection, the distributed measurement of temperature/strain changes from trace to trace, with 1mK/4nε resolution, is theoreticaly and experimentaly demonstrated. The measurand resolution and sensitivity can be tuned by acting on the pulse chirp profile. The technique does not require a frequency sweep, thus greatly decreasing the measurement time and complexity of the system, while maintaining the potential for metric spatial resolutions over tens of kilometers as in conventional ΦOTDR. The technique allows for measurements at kHz rates, while maintaining reliability over several hours.

19.
Sci Total Environ ; 566-567: 1500-1510, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27317136

RESUMO

Different urban resilience measures, such as the increase of urban green areas and the application of white roofs, were evaluated with the WRF-SUEWS modelling system. The case study consists of five heat waves occurring in Porto (Portugal) urban area in a future climate scenario. Meteorological forcing and boundary data were downscaled for Porto urban area from the CMIP5 earth system model MPI-ESM, for the Representative Concentration Pathway RCP8.5 scenario. The influence of different resilience measures on the energy balance components was quantified and compared between each other. Results show that the inclusion of green urban areas increases the evaporation and the availability of surface moisture, redirecting the energy to the form of latent heat flux (maximum increase of +200Wm(-2)) rather than to sensible heat. The application of white roofs increases the solar radiation reflection, due to the higher albedo of such surfaces, reducing both sensible and storage heat flux (maximum reductions of -62.8 and -35Wm(-2), respectively). The conjugations of the individual benefits related to each resilience measure shows that this measure is the most effective one in terms of improving the thermal comfort of the urban population, particularly due to the reduction of both sensible and storage heat flux. The obtained results contribute to the knowledge of the surface-atmosphere exchanges and can be of great importance for stakeholders and decision-makers.

20.
Neurogastroenterol Motil ; 28(1): 101-15, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26526599

RESUMO

BACKGROUND: Cachexia is a significant problem in patients with cancer. The effect of cancer on interstitial cells of Cajal (ICC) and neurons of the gastrointestinal tract have not been studied previously. Although supplementation with L-glutamine 2% may have beneficial effects in cancer-related cachexia, and be protective of ICC in models of oxidative stress such as diabetes, its effects on ICC in cancer have also not been studied. METHODS: Twenty-eight male Wistar rats were divided into four groups: control (C), control supplemented with L-glutamine (CG), Walker 256 tumor (WT), and Walker 256 tumor supplemented with L-glutamine (WTG). Rats were implanted with tumor cells or injected with saline in the right flank. After 14 days, the jejunal tissues were collected and processed for immunohistochemical techniques including whole mounts and cryosections and Western blot analysis. KEY RESULTS: Tumor-bearing rats demonstrate reduced numbers of Myenteric ICC and deep muscular plexus ICC and yet increased Ano1 protein expression and enhanced ICC networks. In addition, there is more nNOS protein expressed in tumor-bearing rats compared to controls. L-glutamine treatment had a variety of effects on ICC that may be related to the disease state and the interaction of ICC and nNOS neurons. Regardless, L-glutamine reduced the size of tumors and also tumor-induced cachexia that was not due to altered food intake. CONCLUSIONS & INFERENCES: There are significant effects on ICC in the Walker 256 tumor model. Although supplementation with L-glutamine has differential and complex effects of ICC, it reduces tumor size and tumor-associated cachexia, which supports its beneficial therapeutic role in cancer.


Assuntos
Caquexia/metabolismo , Carcinoma 256 de Walker/metabolismo , Canais de Cloreto/efeitos dos fármacos , Glutamina/farmacologia , Células Intersticiais de Cajal/efeitos dos fármacos , Jejuno/efeitos dos fármacos , Plexo Mientérico/efeitos dos fármacos , Óxido Nítrico Sintase Tipo I/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Anoctamina-1 , Western Blotting , Carcinoma 256 de Walker/patologia , Canais de Cloreto/metabolismo , Imuno-Histoquímica , Células Intersticiais de Cajal/metabolismo , Masculino , Plexo Mientérico/citologia , Óxido Nítrico Sintase Tipo I/metabolismo , Ratos , Ratos Wistar , Carga Tumoral
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