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1.
Phys Rev Lett ; 123(5): 057403, 2019 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-31491330

RESUMEN

We perform two-dimensional coherent spectroscopy on CdSe/CdZnS core-shell colloidal quantum dots at cryogenic temperatures. In the two-dimensional spectra, sidebands due to electronic coupling with CdSe lattice LO-phonon modes are observed to have evolutions deviating from the exponential dephasing expected from Markovian spectral diffusion, which is instantaneous and memoryless. Comparison to simulations provides evidence that LO-phonon coupling induces energy-gap fluctuations on the finite timescales of nuclear motion. The femtosecond resolution of our technique probes exciton dynamics directly on the timescales of phonon coupling in nanocrystals.

2.
Nanoscale Res Lett ; 10(1): 399, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26464175

RESUMEN

This paper reports the synthesis of silver nanoparticles coated with porous silica (Ag@Silica NPs) using an assisted laser ablation method. This method is a chemical synthesis where one of the reagents (the reducer agent) is introduced in nanometer form by laser ablation of a solid target submerged in an aqueous solution. In a first step, a silicon wafer immersed in water solution was laser ablated for several minutes. Subsequently, an AgNO3 aliquot was added to the aqueous solution. The redox reaction between the silver ions and ablation products leads to a colloidal suspension of core-shell Ag@Silica NPs. The influence of the laser pulse energy, laser wavelength, ablation time, and Ag(+) concentration on the size and optical properties of the Ag@Silica NPs was investigated. Furthermore, the colloidal suspensions were studied by UV-VIS-NIR spectroscopy, X-Ray diffraction, and high-resolution transmission electron microscopy (HRTEM).

3.
J Phys Chem B ; 119(11): 4294-9, 2015 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-25692215

RESUMEN

One of the most important properties of quantum dots (QDs) is their size. Their size will determine optical properties and in a colloidal medium their range of interaction. The most common techniques used to measure QD size are transmission electron microscopy (TEM) and X-ray diffraction. However, these techniques demand the sample to be dried and under a vacuum. This way any hydrodynamic information is excluded and the preparation process may alter even the size of the QDs. Fluorescence correlation spectroscopy (FCS) is an optical technique with single molecule sensitivity capable of extracting the hydrodynamic radius (HR) of the QDs. The main drawback of FCS is the blinking phenomenon that alters the correlation function implicating in a QD apparent size smaller than it really is. In this work, we developed a method to exclude blinking of the FCS and measured the HR of colloidal QDs. We compared our results with TEM images, and the HR obtained by FCS is higher than the radius measured by TEM. We attribute this difference to the cap layer of the QD that cannot be seen in the TEM images.


Asunto(s)
Hidrodinámica , Puntos Cuánticos/química , Compuestos de Cadmio/química , Difusión , Tamaño de la Partícula , Espectrometría de Fluorescencia , Telurio/química
4.
Arq. bras. med. vet. zootec ; 66(6): 1941-1945, 12/2014. graf
Artículo en Portugués | LILACS | ID: lil-735786

RESUMEN

In this work, 25,806 potentially amplifiable microsatellite loci (PAL) were identified in pejerrey, (Odontesthes humensis), with 21% of dinucleotide, 22% trinucleotide, 37% tetranucleotide, 13% pentanucleotide and 7% hexanucleotide. Of the total loci, 167 were classified as "Best PAL", more likely to be variables in populations. The results show that with a small coverage of the genome it was possible to identify a large number of microsatellite loci...


Asunto(s)
Animales , Genoma/genética , Sitios Genéticos/genética , Peces/genética , Acuicultura , Mejoramiento Genético , Repeticiones de Microsatélite/genética
5.
Arq. bras. med. vet. zootec ; 63(5): 1263-1267, out. 2011. tab
Artículo en Inglés | LILACS | ID: lil-605859

RESUMEN

Foram identificadas a divergência e a variabilidade genética, por meio do polimorfismo de seis marcadores microssatélites, de duas populações de Odontesthes bonariensis, utilizadas em manejos de cultivo e com potencial para fornecimento de reprodutores para programas de melhoramento genético. Do total de seis loci, cinco demonstraram eficiência para análise genética nas duas populações de O. bonariensis. A diferenciação genética significante nas populações analisadas pode fornecer a base para futuros programas de melhoramentos genéticos, através da combinação de material das populações divergentes para o desenvolvimento de linhagens ou execução de um programa de seleção.


Asunto(s)
Animales , Mejoramiento Genético , Variación Genética , Repeticiones de Microsatélite , Peces/crecimiento & desarrollo , Peces/genética , Adaptación Biológica , Genoma
6.
Genet Mol Res ; 9(3): 1645-53, 2010 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-20799161

RESUMEN

The goal of this research was to evaluate the ability of the genotyping information available in the Brazilian Criollo Horse Stud Book to describe the genetic variability of the breed and the exclusion probability determined in comparative tests. Altogether, two softwares were used in the analyses of the available genotypes: Cervus 3.0.3 and Genepop 4.0. Eight microsatellite markers totaled 109 alleles, with an average of 13.6 +/- 0.6 alleles per locus. Large differences between expected and observed heterozygosity were ubiquitous (0.821 +/- 0.07 and 0.470 +/- 0.17, respectively). Although the estimated null allele frequency caused initial concern (0.284 +/- 0.199), it is likely that it was a reflection of the inbreeding coefficients found (0.432 +/- 0.184). All loci showed significant deviation from Hardy-Weinberg equilibrium, with heterozygote deficit (P < 0.0001) and genotypic linkage disequilibrium with at least one marker. The high polymorphic information content (0.798 +/- 0.088) could not warrant exclusion power for three loci (HMS7, HMS6 and HTG4) above 50% (0.491 +/- 0.158). However, combined exclusion probability reached 99.61%, a level close to ideal. The results demonstrate the excellent performance of the markers assessed in describing the genetic status of the breed and suggest the considerable ability to establish parentage.


Asunto(s)
Caballos/genética , Animales , Brasil , Genotipo , Desequilibrio de Ligamiento/genética
7.
Acta Neurochir (Wien) ; 148(8): 881-3; discussion 883, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16791431

RESUMEN

BACKGROUND: Trigeminal neuralgia is a common cause of facial pain, characterized by shock-like pain affecting one or more branches of the trigeminal nerve. When conservative treatment fails and microdecompression is not indicated, percutaneous procedures are helpful. This percutaneous approach is done by a puncture up to the Gasserian ganglion, through the foramen ovale. Although simple and safe, this puncture demands some expertise from neurosurgeons. For that, a partnership between neurosurgeons and bio-engineers has developed a model for foramen ovale puncture, allowing practice for residents and young neurosurgeons. METHOD: A model for foramen ovale puncture has been created by interposition of synthetic materials over a skull, simulating the human face. FINDINGS: This model has shown great similarity with that found in conventional surgeries, even upon repeated testing by experienced functional neurosurgeons and young residents. CONCLUSION: This model for foramen ovale puncture training has demonstrated valuable help for initial practicing of this common neurosurgical procedure, particularly in centers where there are not many cadavers available for training.


Asunto(s)
Fosa Craneal Media/cirugía , Modelos Anatómicos , Procedimientos Neuroquirúrgicos/educación , Base del Cráneo/cirugía , Ganglio del Trigémino/cirugía , Neuralgia del Trigémino/cirugía , Ablación por Catéter/métodos , Fosa Craneal Media/anatomía & histología , Desnervación/métodos , Cara/anatomía & histología , Humanos , Internado y Residencia/métodos , Complicaciones Intraoperatorias/etiología , Complicaciones Intraoperatorias/fisiopatología , Complicaciones Intraoperatorias/prevención & control , Neurocirugia/educación , Procedimientos Neuroquirúrgicos/métodos , Elastómeros de Silicona , Base del Cráneo/anatomía & histología , Enseñanza/métodos , Ganglio del Trigémino/anatomía & histología , Ganglio del Trigémino/fisiopatología , Nervio Trigémino/anatomía & histología , Nervio Trigémino/fisiopatología , Nervio Trigémino/cirugía , Neuralgia del Trigémino/etiología , Neuralgia del Trigémino/fisiopatología
8.
Rev. Assoc. Med. Bras. (1992, Impr.) ; 47(4): 296-301, out.-dez. 2001. tab, graf
Artículo en Portugués | LILACS, Sec. Est. Saúde SP | ID: lil-306464

RESUMEN

A utilizaçäo terapêutica de doses elevadas de imunossupressores pode promover diversas complicaçöes, principalmente infecciosas. OBJETIVOS: Avaliar as complicaçöes secundárias ao uso de corticóide e ciclofosfamida em portadores de nefropatias. MÉTODOS: Foram estudados retrospectivamente 76 pacientes atendidos no Hospital das Clínicas da Faculdade de Medicina de Botucatu - UNESP, sendo divididos em três grupos: G1= Lúpus Eritematoso Sistêmico sem lesäo renal (n=15); G2= nefrite lúpica (n=33) e G3= síndrome nefrótica por glomerulopatia idiopática (n=28). RESULTADOS: Näo houve diferença em relaçäo ao tempo de acompanhamento (G1= 42,4 ± 51, G2= 52,3 ± 51, G3= 41,8 ± 47,8 meses), dose total de corticóide utilizada (G1= 20, G2= 28, G3= 16 gramas) e tempo de uso da droga (G1= 20, G2= 26, G3= 14,5 meses). Quanto ao uso de ciclofosfamida, näo houve diferença na percentagem de pacientes que a utilizaram (13 por cento no G1, 51 por cento no G2, 28 por cento no G3), porém pacientes do G1 receberam dose total menor que G2 (mediana de zero e um grama, respectivamente -- p<0.05). Aspecto cushingóide, manifestaçöes gástricas, distúrbios comportamentais, diabetes mellitus e alteraçöes oculares ocorreram nos três grupos, sem diferença estatística. Quanto às complicaçöes infecciosas, aquelas consideradas clinicamente mais graves, foram mais freqüentes no G2 (G1= 6 por cento, G2= 15 por cento, G3= 0 por cento - p<0.05), o mesmo ocorrendo em relaçäo aos óbitos (7 por cento no G1, 30 por cento no G2, 0 por cento no G3 -- p<0.05). CONCLUSÖES: Pacientes portadores de nefrite lúpica apresentaram maior freqüência de complicaçöes infecciosas decorrentes da imunossupressäo prolongada, o que pode representar um marcador de gravidade deste tipo de lesäo


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Inmunosupresores , Lupus Eritematoso Sistémico , Nefritis Lúpica , Metilprednisolona , Prednisona , Estudios Retrospectivos , Estudios de Seguimiento , Corticoesteroides , Ciclofosfamida
9.
Rev Assoc Med Bras (1992) ; 47(4): 296-301, 2001.
Artículo en Portugués | MEDLINE | ID: mdl-11813044

RESUMEN

PURPOSE: To evaluate the therapeutic complications due to the use of immunosupressors in patients with nephropathy. METHODS: 76 patients who had used steroids and cyclophosphamide were retrospectively studied. The cases were divided into three groups: G1= 15 patients with Systemic Lupus Erythematosus without renal lesion; G2= 33 patients with lupus nephritis and G3= 28 patients with nephrotic syndrome owing to idiopathic glomerulopathy. RESULTS: There were no differences related to time of follow up (G1= 42.4 +/- 51, G2= 52.3 +/- 51, G3= 41.8 +/- 47.8 months), total used dosage of steroids (G1= 20, G2= 28, G3= 16 grams) and time of drug use (G1= 20, G2= 26, G3= 14.5 months). About cyclophosphamide use, there was no difference in the percentage of patients who used it (13% in G1, 51% in G2, 28% in G3), but the patients from G1 received lower total dosage than those from G2 (p<0.05). Cushingoid appearance, epigastric distress, psychiatric disorders, diabetes mellitus and ocular alterations occurred in all the three groups, with no statistically significant differences. The infections complications, those considered more severe clinically, were more frequent in G2 (G1= 6%, G2= 15%, G3= 0% - p<0.05), the same occurring with the deaths (7% in G1, 30% in G2, 0% in G3 - p<0.05). CONCLUSION: In patients with lupus nephritis there were more infections complications owing to prolonged immunosuppresion what may indicate a severity marker of this type of lesion.


Asunto(s)
Inmunosupresores/efectos adversos , Lupus Eritematoso Sistémico/tratamiento farmacológico , Corticoesteroides/efectos adversos , Adulto , Ciclofosfamida/efectos adversos , Femenino , Estudios de Seguimiento , Humanos , Lupus Eritematoso Sistémico/complicaciones , Nefritis Lúpica/complicaciones , Nefritis Lúpica/tratamiento farmacológico , Masculino , Metilprednisolona/efectos adversos , Síndrome Nefrótico/complicaciones , Síndrome Nefrótico/tratamiento farmacológico , Prednisona/efectos adversos , Estudios Retrospectivos
10.
Arq Neuropsiquiatr ; 57(1): 111-3, 1999 Mar.
Artículo en Portugués | MEDLINE | ID: mdl-10347736

RESUMEN

We describe a Brazilian family in which one female patient and her three daughters present a clinical course compatible with migraine, preceded by language disorders (aphasia), without paresis. Several aspects related to genetics of migraine are reviewed. We conclude that further genetical studies are necessary to establish if these cases are different sources of well-known migraine subtypes as the familial hemiplegic migraine.


Asunto(s)
Afasia/genética , Trastornos Migrañosos/genética , Adolescente , Adulto , Afasia/complicaciones , Femenino , Hemiplejía , Humanos , Persona de Mediana Edad , Trastornos Migrañosos/complicaciones , Parestesia
11.
Rev Inst Med Trop Sao Paulo ; 37(1): 25-33, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-7569637

RESUMEN

A study was conducted on 16 patients with pemphigus foliaceus, ten of them with the localized form (group G1) and six with the disseminated form (group G2). These patients were submitted to full blood counts, quantitation of mononuclear cell subpopulations by monoclonal antibodies, study of blastic lymphocyte transformation, and quantitation of circulating antibodies by the indirect immunofluorescence test, in order to correlate their clinical signs and symptoms and laboratory data with their immunological profile, and to determine the relationship between circulating autoantibody titers and lesion intensity and course of lesions under treatment. Leucocytosis was observed especially in group G2. All patients showed decreased relative CD3+ and CD4+ values and a tendency to decreased relative values of the CD8+ subpopulation. Blastic lymphocyte transformation indices in the presence of phytohemagglutinin were higher in patients (group G1 + G2) than in controls. The indirect immunofluorescence test was positive in 100% of G2 patients and in 80% of G1 patients. The median value for the titers was higher in group G2 than in group G1. Analysis of the results as a whole permits us to conclude that cell immunity was preserved and that there was a relationship between antibody titers detected by the direct immunofluorescence test and extent of skin lesions.


Asunto(s)
Pénfigo/inmunología , Adolescente , Adulto , Anciano , Formación de Anticuerpos , Recuento de Células Sanguíneas , Femenino , Humanos , Inmunidad Celular , Inmunoglobulina G/sangre , Activación de Linfocitos , Masculino , Persona de Mediana Edad , Pénfigo/epidemiología
12.
Rev Inst Med Trop Sao Paulo ; 37(1): 51-8, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-7569640

RESUMEN

Sixteen patients with endemic pemphigus foliaceus were submitted to nutritional evaluation. Ten had the localized form of the disease (Group G1) and six the disseminated form (Group G2). The patients were submitted to anthropometric measurements (weight, height, Quetelét index, tricipital skin fold, subscapular skin fold, arm circumference, arm muscle circumference, arm area, arm muscle area, and arm adipose area) and to laboratory evaluation by protein electrophoresis. Arm circumference, arm area and arm muscle area showed lower values in G2 than in G1. Weight and arm muscle circumference tended to the lower in G2 than in G1. Protein electrophoresis showed decreased albumin levels in both groups, with lower values in G2. Overall analysis of the results permits us to conclude that patients with endemic pemphigus foliaceus present signs and symptoms of protein, but not calorie, malnutrition and that this malnutrition is more marked in patients with disseminated pemphigus foliaceus.


Asunto(s)
Pénfigo/complicaciones , Deficiencia de Proteína/complicaciones , Adolescente , Adulto , Anciano , Antropometría , Brazo/anatomía & histología , Brasil , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estado Nutricional , Pénfigo/epidemiología
13.
Braz J Med Biol Res ; 25(2): 149-59, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1339511

RESUMEN

1. To study the long term course of passive Heymann nephritis (PHN), 42 adult male Wistar rats were injected with rabbit anti-FX1A serum (PHN group) and 42 rats received normal rabbit serum (control group). Two animals from each group were sacrificed 2 weeks after the inoculation and 10 animals each from the control and PHN groups were sacrificed 4, 13, 25 and 53 weeks later. 2. The PHN group exhibited a significant elevation in 20-h proteinuria which lasted from the first week (control group, 9.19 +/- 0.87; PHN group, 25.3 +/- 2.66) to the 25th week (control group, 22.6 +/- 2.15; PHN group, 66.7 +/- 10.4) except for week 17. From week 29 to week 53 there was no statistical difference between the 2 groups. 3. Light microscopy showed no difference between the kidneys of PHN and control rats. Immunofluorescence microscopy in PHN rats showed granular deposition of autologous and heterologous IgG on the glomerular basement membrane (GBM), whose intensity and pattern did not change during 53 weeks of observation. 4. When examined by electron microscopy the glomeruli of PHN rats showed: a) electron-dense deposits which were initially subepithelial and homogeneous and later intramembranous, granular and often surrounded by an electron-transparent halo; b) focal thickening of the GBM at the sites of intramembranous deposits; c) effacement of podocytes located close to the deposits; d) "penetration" of the podocytes into the GBM associated with the deposits; e) presence of osmiophilic granules in the cytoplasm of the podocytes located inside the GBM similar to the granules of the deposits next to them. The association of the penetration of the podocytes into the GBM with the deposits and the presence of the osmiophilic granules inside the foot process have not been described previously in PHN.


Asunto(s)
Glomerulonefritis/inmunología , Precipitinas/inmunología , Animales , Anticuerpos Heterófilos/inmunología , Membrana Basal/inmunología , Reacción de Biuret , Glomerulonefritis/fisiopatología , Complejo Antigénico de Nefritis de Heymann , Riñón/citología , Riñón/fisiopatología , Masculino , Glicoproteínas de Membrana/inmunología , Microscopía Electrónica , Microscopía Fluorescente , Proteinuria , Conejos , Ratas , Ratas Wistar , Factores de Tiempo
14.
Braz. j. med. biol. res ; 25(2): 149-59, 1992. ilus
Artículo en Inglés | LILACS | ID: lil-109012

RESUMEN

To study the long term course of passive Heymann nephritis (PHN), 42 adult male Wistar rats were injected with rabbit anti-FX1A serum (PHN group) and 42 rats received normal rabbit serum (control group). Two animals from each group were sacrificed 2 weeks after the inoculation and 10 animals each from the control and PHN groups were sacrificed 4, 13, 25 and 53 weeks later. The PHN group exhibited a significant elevation in 20-h proteinuria which lasted from the first week (control group, 9.19 ñ 0.87; PHN group, 25.3 ñ 2.66) to the 25th week (control group, 22.6 ñ 2.15; PHN group, 66.7 ñ 10.4) except for week 17. From week 29 to week 53 there was no statistical difference between the 2 groups. Light microscopy showed no difference between the kidneys of PHN and control rats. Immunofluorescence microscopy in PHN rats showed granular deposition of autologous and heterologous IgG on the glomerular basement m,embrane (GBM), whose intensity and pattern did not change during 53 weeks of observation. When examined by electron microscopyy the glomeruli of PHN rats showed; a) electron-dense deposits which were initial subepithelial and homogeneous and later intramembranous, granular and often surrounded by an electron-transparent halo; b) focal thickening of the GBM at the sites of intramembranous deposits; c) effacement of podocytes located close to the deposits; d) "penetration" of the podocytes into the GBM associated with the deposits; e) presence of osmiophilic granules in the cytoplasm of the podocyte located inside the GBM similar to the granules of the deposits next to them. Them. The association of the penetration of the podocytes into the GBM with the deposits and the presence of the osmiophilic granules inside the foot process have not been described previously in PHN


Asunto(s)
Ratas , Membrana Basal , Células Epiteliales , Glomerulonefritis/inmunología , Microscopía Fluorescente , Proteinuria
17.
Clin Exp Immunol ; 57(3): 591-9, 1984 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-6380837

RESUMEN

To evaluate the effect of 5-fluorouracil (F) and methotrexate-5-fluorouracil association (MTX-F) on nephrotoxic nephritis, seven groups of 10 rats were inoculated with anti-rat glomerular basement membrane serum (AGBMS); five groups were treated with different doses of F, beginning on the 2nd or the 6th day, one group with MTX-F beginning on the 2nd day and one group (control) with distilled water. Twenty-four hour proteinuria was determined weekly until the 71st day. The kidneys were examined histologically and by immunofluorescence. The group treated with F (1.3 mg/100 g body weight) developed a severe glomerulonephritis similar to the control group; (b) the groups treated with F (2.0 mg/100 g body weight) or with MTX-F showed progressively lower proteinuria, less severe histological changes and less intense fluorescence due to autologous antibodies. The best results were observed in the MTX-F group and in the F group treated from the 6th day. These groups presented at the 71st day proteinuria of 84 and 91 mg as compared to 312 mg in the control group, and minimal histological lesions as compared to glomerulosclerosis and tubular atrophy in the control group. We concluded that either F or MTX-F produced significant improvement of nephrotoxic nephritis due to inhibition of autologous antibody production.


Asunto(s)
Fluorouracilo/uso terapéutico , Glomerulonefritis/tratamiento farmacológico , Metotrexato/uso terapéutico , Animales , Quimioterapia Combinada , Técnica del Anticuerpo Fluorescente , Glomerulonefritis/inmunología , Glomerulonefritis/patología , Riñón/inmunología , Riñón/patología , Pruebas de Función Renal , Masculino , Ratas , Ratas Endogámicas
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