Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 43
Filtrar
Más filtros

Intervalo de año de publicación
1.
Braz J Biol ; 83: e274405, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38126632

RESUMEN

The study was conducted to examine the antioxidant activity and evaluate the protective effects of the date seeds powder kentichi against alloxan-induced damage in the liver, kidney, and pancreas in diabetic's rats. Group 1: control group, that did not receive any treatment, Group 2: alloxan was injected intraperitoneally (120 mg/kg body weight) for two days (Diab), Group 3: treated only by date seeds powder added in the diet (300 g/kg) for 6 weeks (DSPK), Group 4: alloxan-diabetic rats treated with date seeds powder (300 g/kg) (DSPK + Diab). Estimations of biochemical parameters in blood were determined. TBARS, SOD, CAT, and GPx activities were determined. A histopathological study was done by immersing pieces of both organs in a fixative solution followed by paraffin hematoxylin-eosin staining. In addition, the antioxidant activities of DSPK were evaluated by DPPH radical scavenging activity, reducing power, and ABTS free radical scavenging. The results revealed that date seeds significantly decreased serum levels of glucose, cholesterol, triglycerides, urea, creatinine, T-protein, ALP, D-bili and T-bili levels. In addition, superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) activities that had been reduced in liver, kidney, and pancreas of the treated group were restored by DSPK treatments and, therefore, the lipid peroxidation level was reduced in the liver, kidney and pancreas tissue compared to the control group. Additionally, the histological structure in these organs was restored after treatment with date seeds powder.


Asunto(s)
Diabetes Mellitus Experimental , Phoeniceae , Ratas , Animales , Antioxidantes/farmacología , Antioxidantes/análisis , Phoeniceae/metabolismo , Aloxano/efectos adversos , Aloxano/análisis , Estrés Oxidativo , Diabetes Mellitus Experimental/inducido químicamente , Diabetes Mellitus Experimental/tratamiento farmacológico , Ratas Wistar , Polvos/efectos adversos , Polvos/análisis , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Superóxido Dismutasa/metabolismo , Semillas , Peroxidación de Lípido
2.
Hum Exp Toxicol ; 38(8): 899-913, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30995857

RESUMEN

Cryptorchidism (CPT), the most common male congenital abnormality, is variably associated with other male reproductive tract problems. We evaluated if cryptorchid rats develop enhanced testicular susceptibility to dibutyl phthalate (DBP) or acrylamide (AA) after extended exposure. Three studies with rats were performed: (1) in utero and postnatal exposure to DBP or AA; (2) establishment of CPT and orchiopexy; and (3) in utero and postnatal exposures to DBP or AA associated with CPT/orchiopexy. Seminiferous tubules were histologically scored according to the severity of lesions: (1) Rats exposed to DBP (score 1.5) or AA (score 1.1) presented mostly preserved spermatogenesis. Some seminiferous tubules showed vacuolated germinative epithelium, germ cell apoptosis, and a Sertoli cell-only (SCO) pattern. (2) CPT (score 3.3) resulted in decreased absolute testes weights, degenerated and SCO tubules, and spermatogenesis arrest that were reversed by orchiopexy (score 1.1). (3) Exposure to DBP or AA with CPT/orchiopexy led to atrophic testes, spermatogenesis arrest, germ cell exfoliation/multinucleation, and SCO tubules (both chemicals score 2.5). Exposure to chemicals such as DBP or AA prevented the recovery of cryptorchid testes by orchiopexy. The possible role of environmental contaminants should be considered when looking for factors that modulate human testicular disorders associated with CPT.


Asunto(s)
Acrilamida/toxicidad , Criptorquidismo/cirugía , Dibutil Ftalato/toxicidad , Testículo/efectos de los fármacos , Animales , Criptorquidismo/patología , Modelos Animales de Enfermedad , Femenino , Masculino , Intercambio Materno-Fetal , Orquidopexia , Embarazo , Ratas Sprague-Dawley , Testículo/patología
3.
Stud Mycol ; 91: 61-78, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30425417

RESUMEN

The fungal kingdom is too large to be discovered exclusively by classical genetics. The access to omics data opens a new opportunity to study the diversity within the fungal kingdom and how adaptation to new environments shapes fungal metabolism. Genomes are the foundation of modern science but their quality is crucial when analysing omics data. In this study, we demonstrate how one gold-standard genome can improve functional prediction across closely related species to be able to identify key enzymes, reactions and pathways with the focus on primary carbon metabolism. Based on this approach we identified alternative genes encoding various steps of the different sugar catabolic pathways, and as such provided leads for functional studies into this topic. We also revealed significant diversity with respect to genome content, although this did not always correlate to the ability of the species to use the corresponding sugar as a carbon source.

4.
Forensic Sci Int Genet ; 35: 156-163, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29783171

RESUMEN

One of the main goals of the Spanish and Portuguese-Speaking Group of the International Society for Forensic Genetics (GHEP-ISFG) is to promote and contribute to the development and dissemination of scientific knowledge in the field of forensic genetics. Due to this fact, GHEP-ISFG holds different working commissions that are set up to develop activities in scientific aspects of general interest. One of them, the Mixture Commission of GHEP-ISFG, has organized annually, since 2009, a collaborative exercise on analysis and interpretation of autosomal short tandem repeat (STR) mixture profiles. Until now, six exercises have been organized. At the present edition (GHEP-MIX06), with 25 participant laboratories, the exercise main aim was to assess mixture profiles results by issuing a report, from the proposal of a complex mock case. One of the conclusions obtained from this exercise is the increasing tendency of participating laboratories to validate DNA mixture profiles analysis following international recommendations. However, the results have shown some differences among them regarding the edition and also the interpretation of mixture profiles. Besides, although the last revision of ISO/IEC 17025:2017 gives indications of how results should be reported, not all laboratories strictly follow their recommendations. Regarding the statistical aspect, all those laboratories that have performed statistical evaluation of the data have employed the likelihood ratio (LR) as a parameter to evaluate the statistical compatibility. However, LR values obtained show a wide range of variation. This fact could not be attributed to the software employed, since the vast majority of laboratories that performed LR calculation employed the same software (LRmixStudio). Thus, the final allelic composition of the edited mixture profile and the parameters employed in the software could explain this data dispersion. This highlights the need, for each laboratory, to define through internal validations its criteria for editing and interpreting mixtures, and to continuous train in software handling.


Asunto(s)
Dermatoglifia del ADN/normas , Genética Forense/normas , Laboratorios/estadística & datos numéricos , Repeticiones de Microsatélite , Sociedades Científicas , Humanos , Funciones de Verosimilitud , Informe de Investigación/normas , Programas Informáticos
5.
Forensic Sci Int Genet ; 25: 63-72, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27500650

RESUMEN

Since 1992, the Spanish and Portuguese-Speaking Working Group of the ISFG (GHEP-ISFG) has been organizing annual Intercomparison Exercises (IEs) coordinated by the Quality Service at the National Institute of Toxicology and Forensic Sciences (INTCF) from Madrid, aiming to provide proficiency tests for forensic DNA laboratories. Each annual exercise comprises a Basic (recently accredited under ISO/IEC 17043: 2010) and an Advanced Level, both including a kinship and a forensic module. Here, we show the results for both autosomal and sex-chromosomal STRs, and for mitochondrial DNA (mtDNA) in two samples included in the forensic modules, namely a mixture 2:1 (v/v) saliva/blood (M4) and a mixture 4:1 (v/v) saliva/semen (M8) out of the five items provided in the 2014 GHEP-ISFG IE. Discrepancies, other than typos or nomenclature errors (over the total allele calls), represented 6.5% (M4) and 4.7% (M8) for autosomal STRs, 15.4% (M4) and 7.8% (M8) for X-STRs, and 1.2% (M4) and 0.0% (M8) for Y-STRs. Drop-out and drop-in alleles were the main cause of errors, with laboratories using different criteria regarding inclusion of minor peaks and stutter bands. Commonly used commercial kits yielded different results for a micro-variant detected at locus D12S391. In addition, the analysis of electropherograms revealed that the proportions of the contributors detected in the mixtures varied among the participants. In regards to mtDNA analysis, besides important discrepancies in reporting heteroplasmies, there was no agreement for the results of sample M4. Thus, while some laboratories documented a single control region haplotype, a few reported unexpected profiles (suggesting contamination problems). For M8, most laboratories detected only the haplotype corresponding to the saliva. Although the GHEP-ISFG has already a large experience in IEs, the present multi-centric study revealed challenges that still exist related to DNA mixtures interpretation. Overall, the results emphasize the need for further research and training actions in order to improve the analysis of mixtures among the forensic practitioners.


Asunto(s)
Cromosomas Humanos X , Cromosomas Humanos Y , Dermatoglifia del ADN , ADN Mitocondrial/genética , Laboratorios/normas , Repeticiones de Microsatélite , Amelogenina/genética , Análisis Químico de la Sangre , Femenino , Genética Forense , Marcadores Genéticos , Haplotipos , Humanos , Masculino , Saliva/química , Semen/química
6.
Eur J Pain ; 20(10): 1741-1752, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27264026

RESUMEN

BACKGROUND: Amylin is a peptide from the calcitonin gene-related peptides (CGRP) family that is expressed by nociceptors. Amylin may modulate pain via a spinal action. METHODS: The effect of amylin's administration on the formalin test of acute and tonic pain was evaluated. Amylin's ability to modulate neuronal activity was analysed by c-Fos expression at the spinal cord lumbar 4-5 region (L4-5) and brain. RESULTS: Amylin subcutaneous administration 20 min prior, but not immediately before formalin, shortened the interphase and anticipated the beginning of the tonic pain phase. Amylin reduced the number of activated spinal cord neurons. Blockade of spinal amylin-receptors by prior L4-5 intrathecal administration of an amylin-receptor antagonist (AC187) attenuated these effects, whereas intrathecal BIBN4096 (CGRP-receptor antagonist) did not, proving that part of amylin's effects were spinally mediated via amylin-receptors. The locus coeruleus and other areas involved in descending modulation and affective responses to pain showed an increased number of activated neurons upon amylin subcutaneous administration, suggesting a role for supraspinal areas in some observed effects. L4-5 intrathecal injection of amylin or AC187 showed that both ligands attenuated tonic pain, but blockade of the amylin-receptor action by AC187 decreased further the number of paw jerks in this period. CONCLUSIONS: Overall, data suggested that amylin modulates pain with an inflammatory component and the autoanalgesic/inhibitory mechanisms occurring in the interphase of the formalin test. Amylin might have affected the nociceptive system at different levels (spinal cord and brain), explaining the different effects observed according to the time of amylin injection. WHAT DOES THIS STUDY ADD?: Amylin modulated formalin interphase and tonic pain behaviours probably by targeting spinal neurons and affecting supraspinal areas involved in affective and modulatory components of pain. Activation of spinal amylin-receptors may contribute to the initiation of inflammatory pain mechanisms.


Asunto(s)
Agonistas de los Receptores de Amilina/farmacología , Polipéptido Amiloide de los Islotes Pancreáticos/farmacología , Dolor/etiología , Dolor/prevención & control , Animales , Encéfalo/metabolismo , Modelos Animales de Enfermedad , Formaldehído , Inyecciones Espinales , Masculino , Dolor/metabolismo , Dimensión del Dolor , Fragmentos de Péptidos , Proteínas Proto-Oncogénicas c-fos/metabolismo , Ratas , Ratas Wistar , Receptores de Péptido Relacionado con el Gen de Calcitonina/metabolismo , Médula Espinal/metabolismo
7.
Nutr J ; 15: 19, 2016 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-26920136

RESUMEN

BACKGROUND: Nutrients such as docosahexaenoic acid (DHA), prebiotics and ß-glucan have been associated with reduced incidence of respiratory illnesses and allergic manifestations (AM). Our objective was to assess if consumption of a cow's milk-based beverage with these and other nutrients supports respiratory, gastrointestinal, and skin health in otherwise well-nourished, healthy children. METHODS: In this double-blind, randomized, controlled trial, healthy children (1-4 years of age) from two daycare centers in Brazil were fed three servings/day of a cow's milk-based beverage (CMBB; n = 125) containing DHA, the prebiotics polydextrose (PDX) and galactooligosaccharides (GOS), ß-glucan, and other key nutrients, or a control cow's milk-based beverage (control; n = 131) for up to 28 weeks. Occurrence of respiratory infections, diarrheal disease and AM was assessed by study pediatricians and the number of episodes were analyzed with the Cochran-Mantel-Haenszel test and the Andersen-Gill model. RESULTS: The CMBB group had fewer episodes of AM, which included allergic rhinitis or conjunctivitis, wheezing, allergic cough, eczema and urticaria, compared to the control group (p = 0.021). The hazard ratio for increased number of episodes of AM was lower in the CMBB group compared to control (HR, 0.64; 95 % CI 0.47-0.89; p = 0.007). There was no difference in the incidence of respiratory infections and diarrheal disease between groups. CONCLUSION: A cow's milk-based beverage containing DHA, PDX/GOS, and yeast ß-glucan, and supplemented with micronutrients, including zinc, vitamin A and iron, when consumed 3 times/day for 28 weeks by healthy 1- to 4-year-old children was associated with fewer episodes of allergic manifestations in the skin and the respiratory tract. TRIAL REGISTRATION: registration number: NCT01431469.


Asunto(s)
Bebidas , Diarrea/epidemiología , Hipersensibilidad/epidemiología , Leche , Infecciones del Sistema Respiratorio/epidemiología , Animales , Biomarcadores/sangre , Brasil , Preescolar , Suplementos Dietéticos , Ácidos Docosahexaenoicos/administración & dosificación , Ácidos Docosahexaenoicos/análisis , Método Doble Ciego , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Lactante , Interleucina-10/sangre , Masculino , Micronutrientes/administración & dosificación , Prebióticos/administración & dosificación , Estudios Prospectivos , Factores Socioeconómicos , Factor de Crecimiento Transformador beta1/sangre , Resultado del Tratamiento , Trisacáridos/administración & dosificación , Trisacáridos/análisis , beta-Glucanos/administración & dosificación , beta-Glucanos/análisis
8.
Transfus Med Hemother ; 42(6): 385-8, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26733770

RESUMEN

BACKGROUND: DNA profiling with sets of highly polymorphic autosomal short tandem repeat (STR) markers has been applied in various aspects of human identification in forensic casework for nearly 20 years. However, in some cases of complex kinship investigation, the information provided by the conventionally used STR markers is not enough, often resulting in low likelihood ratio (LR) calculations. In these cases, it becomes necessary to increment the number of loci under analysis to reach adequate LRs. Recently, it has been proposed that single nucleotide polymorphisms (SNPs) could be used as a supportive tool to STR typing, eventually even replacing the methods/markers now employed. METHODS: In this work, we describe the results obtained in 7 revised complex paternity cases when applying a battery of STRs, as well as 52 human identification SNPs (SNPforID 52plex identification panel) using a SNaPshot methodology followed by capillary electrophoresis. RESULTS: Our results show that the analysis of SNPs, as complement to STR typing in forensic casework applications, would at least increase by a factor of 4 total PI values and correspondent Essen-Möller's W value. CONCLUSIONS: We demonstrated that SNP genotyping could be a key complement to STR information in challenging casework of disputed paternity, such as close relative individualization or complex pedigrees subject to endogamous relations.

9.
Leg Med (Tokyo) ; 16(2): 118-20, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24373741

RESUMEN

The use of autosomal single nucleotide polymorphisms (SNPs) for forensic research has been widely discussed in recent years, mainly because SNPs have important advantages compared to short tandem repeats (STRs). In this study a total of 131 non related individuals from the North of Portugal and 85 immigrant individuals from the Eastern Europe, mainly Ukrainians, equally non related and residing in Portugal, were typed for 52 loci included in the in the SNP for ID 52plex with the SNaPshot™ assay.


Asunto(s)
Dermatoglifia del ADN , Emigrantes e Inmigrantes , Genética de Población , Repeticiones de Microsatélite , Frecuencia de los Genes , Humanos , Portugal , Reacción en Cadena en Tiempo Real de la Polimerasa , Federación de Rusia , Ucrania
10.
Rev Port Pneumol ; 20(2): 101-6, 2014.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-24268918

RESUMEN

A 68 year old woman was submitted to a mediastinal lymphangioleiomyoma resection found in a follow-up study of lower left lung resection due to bronchiectasis complicated by chylothorax. This led to a revaluation of the pulmonary specimen that revealed, in addition to inflammatory bronchiectasis, small spindle cell nodules in the lung parenchyma, similar to minute pulmonary meningothelial-like nodules, but with smooth muscle actin immunohistochemical positivity. The possibility of initial pulmonary development of lymphangioleiomyomatosis is discussed.


Asunto(s)
Neoplasias Pulmonares/patología , Linfangioleiomiomatosis/patología , Linfangiomioma/patología , Neoplasias del Mediastino/patología , Neoplasias Primarias Múltiples/patología , Anciano , Femenino , Humanos
11.
Genet Mol Res ; 12(2): 1074-82, 2013 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-23661433

RESUMEN

We investigated inheritance of resistance to Pepper yellow mosaic virus (PepYMV) in Capsicum baccatum var. pendulum accessions UENF 1616 (susceptible) crossed with UENF 1732 (resistant). Plants from generations P1, P2, F1, F2, BC1:1, and BC1:2 were inoculated and the symptoms were evaluated for 25 days. Subsequently, an area under the disease progress curve was calculated and subjected to generation means analysis. Only the average and epistatic effects were significant. The broad and narrow sense heritability estimates were 35.52 and 21.79%, respectively. The estimate of the minimum number of genes that control resistance was 7, indicating that resistance is polygenic and complex. Thus, methods to produce segregant populations that advocate selection in more advanced generations would be the most appropriate to produce chili pepper cultivars resistant to PepYMV.


Asunto(s)
Capsicum/genética , Resistencia a la Enfermedad/genética , Virus del Mosaico , Enfermedades de las Plantas/genética , Capsicum/inmunología , Capsicum/virología , Cruzamientos Genéticos , Resistencia a la Enfermedad/inmunología , Modelos Genéticos , Virus del Mosaico/inmunología , Enfermedades de las Plantas/inmunología , Enfermedades de las Plantas/virología , Selección Genética
12.
Ann Oncol ; 24(2): 537-542, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23117071

RESUMEN

BACKGROUND: The growth modulation index (GMI) is the ratio of time to progression with the nth line (TTP(n)) of therapy to the TTP(n)(-1) with the n-1th line. GMI >1.33 is considered as a sign of activity in phase II trials. PATIENTS AND METHODS: This retrospective analysis evaluated the concordance between the GMI and the efficacy outcomes in 279 patients with advanced soft tissue sarcoma (ASTS) treated with trabectedin 1.5 mg/m² (24-h infusion every 3 weeks) in four phase II trials. RESULTS: One hundred and forty-two (51%) patients received one prior line and 137 ≥ 2 lines. The median TTP(n) was 2.8 months (range 0.2-26.8), whereas the median TTP(n)(-1) was 4.0 months (0.3-79.5). The median GMI was 0.6 (0.0-14.4). Overall, 177 patients (63%) had a GMI <1; 21 (8%) a GMI equal to 1-1.33 and 81 (29%) a GMI >1.33, which correlated with the median overall survival in those patients (9.1, 13.9 and 23.8 months, respectively, P = 0.0005). A high concordance rate between the GMI and response rate (P < 0.0001) and progression-free survival (PFS, P < 0.0001) was observed. Good performance status (PS) was the only factor associated with GMI >1.33 (PS = 0; P < 0.04). CONCLUSIONS: A high GMI was associated with favorable efficacy outcomes in patients treated with trabectedin. Further research is needed to assess GMI as an indicator in this setting.


Asunto(s)
Antineoplásicos Alquilantes/uso terapéutico , Proliferación Celular/efectos de los fármacos , Dioxoles/uso terapéutico , Sarcoma/tratamiento farmacológico , Tetrahidroisoquinolinas/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Antibióticos Antineoplásicos/uso terapéutico , Supervivencia sin Enfermedad , Doxorrubicina/uso terapéutico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Terapia Recuperativa , Sarcoma/metabolismo , Sarcoma/mortalidad , Sarcoma/patología , Trabectedina , Resultado del Tratamiento , Adulto Joven
14.
Arq. bras. med. vet. zootec ; 63(3): 670-677, June 2011. ilus, tab
Artículo en Inglés | LILACS | ID: lil-595584

RESUMEN

The influence of fatty acid composition of the diets on the productive performance and on cold and heat tolerance of juvenile freshwater angelfish (Pterophyllum scalare), in three different phases, was studied. Phase I studied the productive performance of freshwater angelfish in a completely randomized experimental design with four treatments, canola, linseed, olive and soybean oils and four replicates during 50 days using 192 fish in 16 aquaria. Phase II studied the cold tolerance of juvenile freshwater angelfish using 72 juvenile freshwater angelfish, coming from phase I and maintained in 12 aquaria climatized chamber. The temperature was reduced 1ºC per day, until the observation of 100 percent fish mortality. Phase III, it was studied the heat tolerance of juvenile freshwater angelfish employing an identical procedure to phase II, but with a daily increase of 1ºC. Significant differences (P>0.05) were not observed for any parameters evaluated. Thus, it was concluded that the type of vegetable oil (canola, linseed, olive and soybean) used as a diet supplement did not affect the productive performance, nor the tolerance to cold and heat, of juvenile freshwater angelfish.


Avaliou-se a influência da suplementação de lipídeos na dieta, com diferentes composições de ácidos graxos, sobre o desempenho produtivo e tolerância ao frio e ao calor de juvenis de acará-bandeira (Pterophyllum scalare). O experimento foi realizado em três fases. Na fase um avaliou-se o desempenho produtivo dos peixes em delineamento inteiramente ao acaso com quatro tratamentos - óleos de canola, linhaça, oliva e soja - e quatro repetições, durante 50 dias usando 192 peixes distribuídos em 16 aquários. Na segunda fase, avaliou-se a tolerância ao frio, usando 72 peixes, procedentes da fase um, distribuídos em 12 aquários e mantidos em câmara climatizada. A temperatura foi reduzida de 1ºC por dia até a observação de 100 por cento de mortalidade dos peixes. Na fase três, avaliou-se a tolerância ao calor com procedimentos semelhantes aos da fase dois, porém a temperatura foi elevada 1ºC por dia. Não foram observadas diferenças significativas (P>0,05) para os parâmetros avaliados. Conclui-se que a suplementação de óleos vegetais nas dietas não inferiu no desempenho produtivo e na tolerância ao frio e ao calor de juvenis de acará-bandeira.


Asunto(s)
Animales , Dieta/veterinaria , Ácidos Grasos , Peces , Lípidos , Aceites de Plantas , Temperatura Corporal , Sobrevida
15.
Opt Express ; 17(16): 14121-31, 2009 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-19654822

RESUMEN

This paper proposes a new design methodology for discrete multi-pumped Raman amplifier. In a multi-objective optimization scenario, in a first step the whole solution-space is inspected by a CW analytical formulation. Then, the most promising solutions are fully investigated by a rigorous numerical treatment and the Raman amplification performance is thus determined by the combination of analytical and numerical approaches. As an application of our methodology we designed an photonic crystal fiber Raman amplifier configuration which provides low ripple, high gain, clear eye opening and a low power penalty. The amplifier configuration also enables to fully compensate the dispersion introduced by a 70-km singlemode fiber in a 10 Gbit/s system. We have successfully obtained a configuration with 8.5 dB average gain over the C-band and 0.71 dB ripple with almost zero eye-penalty using only two pump lasers with relatively low pump power.


Asunto(s)
Amplificadores Electrónicos , Tecnología de Fibra Óptica/instrumentación , Rayos Láser , Espectrometría Raman/instrumentación , Simulación por Computador , Diseño Asistido por Computadora , Diseño de Equipo , Análisis de Falla de Equipo , Luz , Modelos Teóricos , Fotones , Dispersión de Radiación
16.
Opt Express ; 17(25): 23169-80, 2009 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-20052245

RESUMEN

In this paper we discuss the use of photonic crystal fibers (PCFs) as discrete devices for simultaneous wideband dispersion compensation and Raman amplification. The performance of the PCFs in terms of gain, ripple, optical signal-to-noise ratio (OSNR) and required fiber length for complete dispersion compensation is compared with conventional dispersion compensating fibers (DCFs). The main goal is to determine the minimum PCF loss beyond which its performance surpasses a state-of-the-art DCF and justifies practical use in telecommunication systems.


Asunto(s)
Amplificadores Electrónicos , Fibras Ópticas , Espectrometría Raman/instrumentación , Diseño Asistido por Computadora , Cristalización , Diseño de Equipo , Análisis de Falla de Equipo
17.
J Chromatogr A ; 1189(1-2): 435-43, 2008 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-18164022

RESUMEN

This work presents a RP-HPLC method for the simultaneous quantification of free amino acids and biogenic amines in liquid food matrices and the results of the application to honey and wine samples obtained from different production processes and geographic origins. The developed methodology is based on a pre-column derivatization with o-phthaldialdehyde carried out in the sample injection loop. The compounds were separated in a Nova-Pack RP-C(18) column (150 mm x 3.9 mm, 4 microm) at 35 degrees C. The mobile phase used was a mixture of phase A: 10 mM sodium phosphate buffer (pH 7.3), methanol and tetrahydrofuran (91:8:1); and phase B: methanol and phosphate buffer (80:20), with a flow rate of 1.0 ml/min. Fluorescence detection was used at an excitation wavelength of 335 nm and an emission wavelength of 440 nm. The separation and quantification of 19 amino acids and 6 amines was carried out in a single run as their OPA/MCE derivatives elute within 80 min, ensuring a reproducible quantification. The method showed to be adequate for the purpose, with an average RSD of 2% for the different amino acids; detection limits varying between 0.71 mg/l (Asn) and 8.26 mg/l (Lys) and recovery rates between 63.0% (Cad) and 98.0% (Asp). The amino acids present at the highest concentration in honey and wine samples were phenylalanine and arginine, respectively. Only residual levels of biogenic amines were detected in the analysed samples.


Asunto(s)
Aminoácidos/análisis , Aminas Biogénicas/análisis , Cromatografía Líquida de Alta Presión/métodos , Miel/análisis , Vino/análisis , o-Ftalaldehído/química , Aminoácidos/química , Aminas Biogénicas/química , Concentración de Iones de Hidrógeno , Reproducibilidad de los Resultados
18.
Forensic Sci Int ; 170(1): 62-7, 2007 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-16759830

RESUMEN

Allele frequencies and population data for 17 Y-STR loci included in a new commercial kit that has recently been available, the AmpFlSTR Y-filer PCR amplification kit (Applied Biosystems), that permits the simultaneous amplification of all the markers included in the actually used European "extended haplotype", DYS19, DYS189I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385I/II, DYS438, DYS439 and also DYS437, DYS448, DYS456, DYS458, DYS635 and Y GATA H4, were obtained from a sample of 175 healthy unrelated males and 45 father-son pairs from the North of Portugal. A total of 171 haplotypes were identified, of which 167 were unique and 4 were found in 2 individuals. The haplotype diversity (99.97%) and discrimination capacity (95.43%) were calculated. We report some non-standard situations, such as allele duplications and mutations. We also report a case of disputed paternity in which duplicated alleles plus an inconsistency of the transmitted alleles appeared.


Asunto(s)
Cromosomas Humanos Y , Frecuencia de los Genes , Genética de Población , Secuencias Repetidas en Tándem , Dermatoglifia del ADN , Humanos , Masculino , Reacción en Cadena de la Polimerasa , Portugal
19.
Talanta ; 74(1): 91-103, 2007 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-18371617

RESUMEN

The volatile composition from four types of multifloral Portuguese (produced in Madeira Island) honeys was investigated by a suitable analytical procedure based on dynamic headspace solid-phase microextraction (HS-SPME) followed by thermal desorption gas chromatography-quadrupole mass spectrometry detection (GC-qMS). The performance of five commercially available SPME fibres: 100 microm polydimethylsiloxane, PDMS; 85 microm polyacrylate, PA; 50/30 microm divinylbenzene/carboxen on polydimethylsiloxane, DVB/CAR/PDMS (StableFlex); 75 microm carboxen/polydimethylsiloxane, CAR/PDMS, and 65 microm carbowax/divinylbenzene, CW/DVB; were evaluated and compared. The highest amounts of extract, in terms of the maximum signal obtained for the total volatile composition, were obtained with a DVB/CAR/PDMS coating fibre at 60 degrees C during an extraction time of 40 min with a constant stirring at 750 rpm, after saturating the sample with NaCl (30%). Using this methodology more than one hundred volatile compounds, belonging to different biosynthetic pathways were identified, including monoterpenols, C13-norisoprenoids, sesquiterpenes, higher alcohols, ethyl esters and fatty acids. The main components of the HS-SPME samples of honey were in average ethanol, hotrienol, benzeneacetaldehyde, furfural, trans-linalool oxide and 1,3-dihydroxy-2-propanone.


Asunto(s)
Miel/análisis , Microextracción en Fase Sólida/instrumentación , Resinas Acrílicas/química , Dimetilpolisiloxanos/química , Cromatografía de Gases y Espectrometría de Masas/métodos , Polietilenglicoles/química , Portugal , Siliconas/química , Microextracción en Fase Sólida/métodos , Compuestos de Vinilo/química , Volatilización
20.
Hum Mutat ; 26(6): 520-8, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16220553

RESUMEN

A collaborative work was carried out by the Spanish and Portuguese ISFG Working Group (GEP-ISFG) to estimate Y-STR mutation rates. Seventeen Y chromosome STR loci (DYS19, DYS385, DYS389I and II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438, DYS439, DYS460, DYS461, DYS635 [GATA C4], GATA H4, and GATA A10) were analyzed in a sample of 3,026 father/son pairs. Among 27,029 allele transfers, 54 mutations were observed, with an overall mutation rate across the 17 loci of 1.998 x 10(-3) (95% CI, 1.501 x 10(-3) to 2.606 x 10(-3)). With just one exception, all of the mutations were single-step, and they were observed only once per gametogenesis. Repeat gains were more frequent than losses, longer alleles were found to be more mutable, and the mutation rate seemed to increase with the father's age. Hum Mutat 26(6), 520-528, 2005. (c) 2005 Wiley-Liss, Inc.


Asunto(s)
Cromosomas Humanos Y/genética , Repeticiones de Microsatélite/genética , Mutación , Factores de Edad , Alelos , Secuencia de Bases , Análisis Mutacional de ADN , Frecuencia de los Genes , Marcadores Genéticos , Humanos , Masculino , Datos de Secuencia Molecular
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA