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1.
Phys Rev Lett ; 123(5): 057403, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31491330

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-26464175

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-25692215

RESUMO

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.


Assuntos
Hidrodinâmica , Pontos Quânticos/química , Compostos de Cádmio/química , Difusão , Tamanho da Partícula , Espectrometria de Fluorescência , Telúrio/química
4.
Arq. bras. med. vet. zootec ; 66(6): 1941-1945, 12/2014. graf
Artigo em Português | LILACS | ID: lil-735786

RESUMO

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...


Assuntos
Animais , Genoma/genética , Loci Gênicos/genética , Peixes/genética , Aquicultura , Melhoramento Genético , Repetições de Microssatélites/genética
5.
Arq. bras. med. vet. zootec ; 63(5): 1263-1267, out. 2011. tab
Artigo em Inglês | LILACS | ID: lil-605859

RESUMO

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.


Assuntos
Animais , Melhoramento Genético , Variação Genética , Repetições de Microssatélites , Peixes/crescimento & desenvolvimento , Peixes/genética , Adaptação Biológica , Genoma
6.
Genet Mol Res ; 9(3): 1645-53, 2010 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-20799161

RESUMO

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.


Assuntos
Cavalos/genética , Animais , Brasil , Genótipo , Desequilíbrio de Ligação/genética
7.
Acta Neurochir (Wien) ; 148(8): 881-3; discussion 883, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16791431

RESUMO

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.


Assuntos
Fossa Craniana Média/cirurgia , Modelos Anatômicos , Procedimentos Neurocirúrgicos/educação , Base do Crânio/cirurgia , Gânglio Trigeminal/cirurgia , Neuralgia do Trigêmeo/cirurgia , Ablação por Cateter/métodos , Fossa Craniana Média/anatomia & histologia , Denervação/métodos , Face/anatomia & histologia , Humanos , Internato e Residência/métodos , Complicações Intraoperatórias/etiologia , Complicações Intraoperatórias/fisiopatologia , Complicações Intraoperatórias/prevenção & controle , Neurocirurgia/educação , Procedimentos Neurocirúrgicos/métodos , Elastômeros de Silicone , Base do Crânio/anatomia & histologia , Ensino/métodos , Gânglio Trigeminal/anatomia & histologia , Gânglio Trigeminal/fisiopatologia , Nervo Trigêmeo/anatomia & histologia , Nervo Trigêmeo/fisiopatologia , Nervo Trigêmeo/cirurgia , Neuralgia do Trigêmeo/etiologia , Neuralgia do Trigêmeo/fisiopatologia
8.
Rev. Assoc. Med. Bras. (1992) ; 47(4): 296-301, out.-dez. 2001. tab, graf
Artigo em Português | LILACS, Sec. Est. Saúde SP | ID: lil-306464

RESUMO

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


Assuntos
Humanos , Masculino , Feminino , Adulto , Imunossupressores , Lúpus Eritematoso Sistêmico , Nefrite Lúpica , Metilprednisolona , Prednisona , Estudos Retrospectivos , Seguimentos , Corticosteroides , Ciclofosfamida
9.
Rev Assoc Med Bras (1992) ; 47(4): 296-301, 2001.
Artigo em Português | MEDLINE | ID: mdl-11813044

RESUMO

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.


Assuntos
Imunossupressores/efeitos adversos , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Corticosteroides/efeitos adversos , Adulto , Ciclofosfamida/efeitos adversos , Feminino , Seguimentos , Humanos , Lúpus Eritematoso Sistêmico/complicações , Nefrite Lúpica/complicações , Nefrite Lúpica/tratamento farmacológico , Masculino , Metilprednisolona/efeitos adversos , Síndrome Nefrótica/complicações , Síndrome Nefrótica/tratamento farmacológico , Prednisona/efeitos adversos , Estudos Retrospectivos
10.
Arq Neuropsiquiatr ; 57(1): 111-3, 1999 Mar.
Artigo em Português | MEDLINE | ID: mdl-10347736

RESUMO

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.


Assuntos
Afasia/genética , Transtornos de Enxaqueca/genética , Adolescente , Adulto , Afasia/complicações , Feminino , Hemiplegia , Humanos , Pessoa de Meia-Idade , Transtornos de Enxaqueca/complicações , Parestesia
11.
Rev Inst Med Trop Sao Paulo ; 37(1): 25-33, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7569637

RESUMO

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.


Assuntos
Pênfigo/imunologia , Adolescente , Adulto , Idoso , Formação de Anticorpos , Contagem de Células Sanguíneas , Feminino , Humanos , Imunidade Celular , Imunoglobulina G/sangue , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Pênfigo/epidemiologia
12.
Rev Inst Med Trop Sao Paulo ; 37(1): 51-8, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7569640

RESUMO

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.


Assuntos
Pênfigo/complicações , Deficiência de Proteína/complicações , Adolescente , Adulto , Idoso , Antropometria , Braço/anatomia & histologia , Brasil , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Pênfigo/epidemiologia
13.
Braz J Med Biol Res ; 25(2): 149-59, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1339511

RESUMO

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.


Assuntos
Glomerulonefrite/imunologia , Precipitinas/imunologia , Animais , Anticorpos Heterófilos/imunologia , Membrana Basal/imunologia , Reação de Biureto , Glomerulonefrite/fisiopatologia , Complexo Antigênico da Nefrite de Heymann , Rim/citologia , Rim/fisiopatologia , Masculino , Glicoproteínas de Membrana/imunologia , Microscopia Eletrônica , Microscopia de Fluorescência , Proteinúria , Coelhos , Ratos , Ratos Wistar , Fatores de Tempo
14.
Braz. j. med. biol. res ; 25(2): 149-59, 1992. ilus
Artigo em Inglês | LILACS | ID: lil-109012

RESUMO

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


Assuntos
Ratos , Membrana Basal , Células Epiteliais , Glomerulonefrite/imunologia , Microscopia de Fluorescência , Proteinúria
17.
Clin Exp Immunol ; 57(3): 591-9, 1984 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6380837

RESUMO

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.


Assuntos
Fluoruracila/uso terapêutico , Glomerulonefrite/tratamento farmacológico , Metotrexato/uso terapêutico , Animais , Quimioterapia Combinada , Imunofluorescência , Glomerulonefrite/imunologia , Glomerulonefrite/patologia , Rim/imunologia , Rim/patologia , Testes de Função Renal , Masculino , Ratos , Ratos Endogâmicos
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