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1.
Appl Surf Sci ; 530: 147294, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32834267

RESUMO

InP-In2O3 colloidal quantum dots (QDs) synthesized by a single-step chemical method without injection of hot precursors (one-pot) were investigated. Specifically, the effect of the tris(trimethylsilyl)phosphine, P(TMS)3, precursor concentration on the QDs properties was studied to effectively control the size and shape of the samples with a minimum size dispersion. The effect of the P(TMS)3 precursor concentration on the optical, structural, chemical surface, and electronic properties of InP-In2O3 QDs is discussed. The absorption spectra of InP-In2O3 colloids, obtained by both UV-Vis spectrophotometry and photoacoustic spectroscopy, showed a red-shift in the high-energy regime as the concentration of the P(TMS)3 increased. In addition, these results were used to determine the band-gap energy of the InP-In2O3 nanoparticles, which changed between 2.0 and 2.9 eV. This was confirmed by Photoluminescence spectroscopy, where a broad-band emission displayed from 2.0 to 2.9 eV is associated with the excitonic transition of the InP and In2O3 QDs. In2O3 and InP QDs with diameters ranging approximately from 8 to 10 nm and 6 to 9 nm were respectively found by HR-TEM. The formation of the InP and In2O3 phases was confirmed by X-ray Photoelectron Spectroscopy.

2.
Luminescence ; 35(5): 781-787, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32030872

RESUMO

This study reports the structural and optical properties of CdS/ZnTiO3 nanocomposites prepared using a chemical bath and different titanate concentrations. Commercial ZnTiO3 nanoparticles were introduced into a chemical bath that had been used to produce CdS semiconductor nanoparticles (NPs). Here, the growing CdS crystallites precipitated onto the suspended zinc titanate NPs. X-ray diffraction patterns revealed that samples of CdS/ZnTiO3 nanopowders were made of cubic ZnTiO3 and hexagonal CdS wurtzite. The morphology of the particles was studied using transmission electron microscopy and scanning electron microscopy images. These images demonstrated the different characteristics of the CdS/ZnTiO3 nanocomposites and their dependence on titanate concentration when placed into the CdS-growing solution. Photoluminescence spectra showed three main emission bands for the electron transitions in the CdS/ZnTiO3 composite. This composite produced three photoluminescence bands, the intensities of which depended on composite shape, which in turn depended on the relative concentrations of CdS and ZnTiO3 .


Assuntos
Compostos de Cádmio/química , Medições Luminescentes , Nanoestruturas/química , Óxidos/química , Sulfetos/química , Titânio/química , Zinco/química , Tamanho da Partícula , Processos Fotoquímicos , Porosidade , Semicondutores , Propriedades de Superfície
3.
Graefes Arch Clin Exp Ophthalmol ; 258(1): 63-70, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31758258

RESUMO

PURPOSE: To analyse the influence of renal function on the outcomes of vitrectomy for tractional-related complications in cases of severe proliferative diabetic retinopathy (PDR). METHODS: Retrospective consecutive case series of 109 eyes that underwent vitreoretinal interventions for traction-related complications of severe PDR from 2014 to 2017. Data collected included patient demographics, best-corrected visual acuity (BCVA), surgical complications, and systemic markers including HbA1c and estimated glomerular filtration rate (eGFR). Renal function categories were defined as low (eGFR < 30 mL/min/1.73 m2), medium (eGFR 30-60 mL/min/1.73 m2), and normal (eGFR > 60 mL/min/1.73m 2). RESULTS: A total of 109 eyes (56% (n = 61) female) were included in the study. Overall, mean baseline BCVA improved from 1.33 logMAR to 0.91 logMAR (p < 0.001) postoperatively. Patients with low eGFR had significantly worse baseline BCVA (p = 0.039) and demonstrated greater improvement in mean BCVA (p = 0.059). Multivariate regression analysis indicated that seven predictors explained 65.5% of the variance (R2 = 0.655, F(11,97) = 16.7, p < 0.01). CONCLUSIONS: Reduced renal function does not adversely affect visual outcomes of vitrectomy for traction-related complications of PDR.


Assuntos
Retinopatia Diabética/cirurgia , Acuidade Visual , Vitrectomia/métodos , Vitreorretinopatia Proliferativa/cirurgia , Adulto , Idoso , Retinopatia Diabética/complicações , Retinopatia Diabética/diagnóstico , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Vitreorretinopatia Proliferativa/diagnóstico , Vitreorretinopatia Proliferativa/etiologia , Adulto Jovem
4.
Transplant Proc ; 50(2): 454-457, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29579826

RESUMO

BACKGROUND: Cardiovascular disease accounts for 35% to 50% of the causes of mortality in chronic kidney disease. The majority of patients in substitution therapy in Mexico are subdialyzed owing to limited economic resources. This produces more cardiac deterioration than described in the statistics and has a direct impact on the prognosis of kidney transplantation. The aim of this work was to demonstrate and to quantify the improvement in the echocardiographic parameters 6 months after renal transplantation in patients with stable renal function. METHODS: This was an observational, analytic, prospective study of 23 patients with chronic kidney disease who received transplants in 2016 and had a glomerular filtration rate ≥80 mL/min (Chronic Kidney Disease-Epidemiology Collaboration) 6 months after transplantation. RESULTS: Echocardiographic results showed an increase in the left ventricular ejection fraction from 57.17 ± 10.46% to 64.09 ± 9.8%, an increase in the right ventricular ejection fraction from 0.56 ± 0.09% to 0.60 ± 0.08% and a reduction of the pulmonary arterial systolic pressure from 44.57 ± 13.88 mm Hg to 39.74 ± 11.04 mm Hg. There were also decreases in mitral regurgitation from 1.0 to 0.43, tricuspid insufficiency from 1.35 to 0.43, pulmonary insufficiency from 0.48 to 0.04, and aortic insufficiency from 0.35 to 0.04, all of these significant with P < .05. CONCLUSIONS: There was a significant improvement in cardiovascular function in our population 6 months after transplantation, despite the fact that renal transplantation is performed with greater cardiac deterioration than described in patients in other countries.


Assuntos
Cardiopatias/etiologia , Cardiopatias/fisiopatologia , Transplante de Rim , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/cirurgia , Idoso , Ecocardiografia , Feminino , Humanos , Masculino , México , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos
5.
Transplant Proc ; 48(2): 583-7, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27110008

RESUMO

INTRODUCTION: A lot of evidence has demonstrated the importance of different cytokines in acute renal rejection. Previous studies have examined the presence or absence of interleukin (IL)-10 in related immunopathologic rejection grafts as well as other interleukins. Studies in human transplantation show elevated levels of IL-10 and gamma interferon (INF-γ) in inflammation and rejection. OBJECTIVE: The objective of this study was to demonstrate the lack of association of elevated urinary levels of IL-10 and IFN in the presence of active inflammation. METHODS: An observational, descriptive, cross-sectional study conducted in transplant recipients at 12 months of follow-up after renal transplantation. In those who were held biopsy after renal transplantation at one year follow-up, or allograft dysfunction, we also measured IL-10 and INF-γ in the urine. The following were considered as variables: age, body mass index (BMI), gender, transplant type, creatinine, chronic kidney disease epidemiology collaboration equation, (CKD-EPI), modification of diet in renal disease study equation (MDRD), Banff classification, and levels of IL-10 and INF-γ. Statistical analysis was performed calculating a sample size of 25 patients, with an alpha bias of 0.05%, yielding measures of central tendency and determining no association between levels of IL-10 and INF-γ with the presence of rejection using SPSS 21.0 program. RESULTS: A total of 50 patients, 34 (68%) males, 16 (32%) females, with an average 31.7 ± 9.9 years, weight of 64.91 ± 13.84 kg, size 1.60 ± 0.10 m and 24.97 ± 4.07 BMI were included,39 (78%) living donor and 11 (22%) cadaveric. Twenty-six (52%) showed inflammation in the biopsy and 24 (48%) showed none. Mean creatinine was 1.81 ± 1.5, and the estimated glomerular filtration rate (eGFR) was 55.27 ± 22.46, 65.76 ± 26.7. (MDRD and CKD-EPI, respectively). No statistical difference was found in the levels of IL-10 and IFN-γ using analysis of variance. (ANOVA; P = .467 and P = .063, respectively) Based on Banff, the inflammation on biopsy score was 2.78 ± 2.84. There was statistical significance (P < .05) with respect to the Cr and eGFR by different equations. There were no significant interactions between cytokine levels and more than 1 factor. (as indicated by P < .2). DISCUSSION AND CONCLUSIONS: No significant differences were observed in the level of interleukins in patients with and without inflammation, denoting an adequate immunosuppression in most of these patients. Determination of inflammatory cytokines in urine could be used as a determinant of a good immunosuppression status, rather than as an early marker of rejection.


Assuntos
Rejeição de Enxerto/urina , Inflamação/urina , Interferon gama/urina , Interleucina-10/urina , Transplante de Rim , Rim/fisiopatologia , Transplantados , Adulto , Biomarcadores/urina , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Feminino , Seguimentos , Taxa de Filtração Glomerular/fisiologia , Rejeição de Enxerto/diagnóstico , Humanos , Masculino , Insuficiência Renal Crônica/fisiopatologia , Fatores de Tempo , Transplante Homólogo
6.
Arch. Soc. Esp. Oftalmol ; 91(4): 195-197, abr. 2016. ilus
Artigo em Espanhol | IBECS | ID: ibc-150689

RESUMO

CASO CLÍNICO: Niña de 6 años con artritis psoriásica juvenil (APJ) y uveítis anterior bilateral complicada, presentó múltiples complicaciones que requirieron 5 procedimientos quirúrgicos. Pese al curso agresivo de la inflamación ocular, conservó una buena agudeza visual. La artritis (necesaria para el diagnóstico de APJ) apareció años después de los síntomas oculares y mostró buena respuesta inicial al adalimumab. DISCUSIÓN: El diagnóstico definitivo de APJ fue realizado años después del inicio de los síntomas. Además, la paciente conservó buena agudeza visual a pesar de su complicada evolución. Finalmente, mostró una respuesta clínica satisfactoria a la terapia con inhibidores del factor de necrosis tumoral


CASE REPORT: A 6 year-old girl with juvenile psoriatic arthritis (JPsA) and bilateral complicated anterior uveitis developed several ocular complications that required 5 surgical procedures. Despite the aggressive course of ocular inflammation, her visual acuity remained good. Arthritis (main criterion for the diagnosis of JPsA) appeared years after ocular involvement. She showed a good anti-tumour necrosis factor initial response. DISCUSSION: The definitive diagnosis of JPsA was established years after the onset of symptoms. In addition, the patient maintained a good visual acuity, despite its complicated disease course. Finally, she showed a good clinical response to adalimumab


Assuntos
Humanos , Feminino , Criança , Uveíte Anterior/complicações , Uveíte Anterior/diagnóstico , Uveíte Anterior/terapia , Artrite Juvenil/complicações , Artrite Juvenil/diagnóstico , Artrite Juvenil/terapia , Uveíte Anterior/classificação , Uveíte Anterior/etiologia , Artrite Juvenil/classificação , Artrite Juvenil/prevenção & controle
7.
Arch Soc Esp Oftalmol ; 91(4): 195-7, 2016 Apr.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-26743185

RESUMO

CASE REPORT: A 6 year-old girl with juvenile psoriatic arthritis (JPsA) and bilateral complicated anterior uveitis developed several ocular complications that required 5 surgical procedures. Despite the aggressive course of ocular inflammation, her visual acuity remained good. Arthritis (main criterion for the diagnosis of JPsA) appeared years after ocular involvement. She showed a good anti-tumour necrosis factor initial response. DISCUSSION: The definitive diagnosis of JPsA was established years after the onset of symptoms. In addition, the patient maintained a good visual acuity, despite its complicated disease course. Finally, she showed a good clinical response to adalimumab.


Assuntos
Artrite Psoriásica/complicações , Fator de Necrose Tumoral alfa/uso terapêutico , Uveíte Anterior/etiologia , Artrite Juvenil , Criança , Feminino , Humanos , Uveíte Anterior/tratamento farmacológico
8.
Arch. Soc. Esp. Oftalmol ; 90(7): 344-347, jul. 2015. ilus
Artigo em Espanhol | IBECS | ID: ibc-138258

RESUMO

CASO CLÍNICO: Una niña de 4 años ingresa por politraumatismo grave por arrollamiento. Durante la evolución se le diagnostica de parálisis completa del tercer par del ojo derecho y retinopatía de Purtscher en ojo izquierdo. DISCUSIÓN: La retinopatía de Purtscher es poco frecuente. El diagnóstico es clínico y su tratamiento no está estandarizado aunque los corticoides sistémicos podrían mejorar el pronóstico visual. Las parálisis deL tercer par traumáticas tienen baja tendencia a la recuperación espontánea. El uso de toxina botulínica en niños podría mejorar la tasa de recuperación total y podría ser útil para acelerar la resolución y así permitir binocularidad y evitar la ambliopía


CASE REPORT: A 4 year-old girl was referred to our hospital after have suffered a severe accident. The patient was diagnosed with complete third nerve palsy in her right eye and Purtscher retinopathy in her left eye. DISCUSSION: Purtscher retinopathy is a rare condition. The diagnosis is made on clinical ground and its treatment is not well defined although it is believed that systemic steroids could improve the visual outcome. Traumatic third nerve palsy has a poor spontaneous recovery. The use of botulinum toxin might be useful in children to improve the recovery rate, maintaining binocularity, and avoiding amblyopia in other cases


Assuntos
Pré-Escolar , Feminino , Humanos , Doenças do Nervo Oculomotor/diagnóstico , Traumatismos Craniocerebrais/complicações , Toxinas Botulínicas/uso terapêutico , Traumatismo Múltiplo/complicações
9.
Arch Soc Esp Oftalmol ; 90(7): 344-7, 2015 Jul.
Artigo em Espanhol | MEDLINE | ID: mdl-25443190

RESUMO

CASE REPORT: A 4 year-old girl was referred to our hospital after have suffered a severe accident. The patient was diagnosed with complete third nerve palsy in her right eye and Purtscher retinopathy in her left eye. DISCUSSION: Purtscher retinopathy is a rare condition. The diagnosis is made on clinical ground and its treatment is not well defined although it is believed that systemic steroids could improve the visual outcome. Traumatic third nerve palsy has a poor spontaneous recovery. The use of botulinum toxin might be useful in children to improve the recovery rate, maintaining binocularity, and avoiding amblyopia in other cases.


Assuntos
Traumatismos Craniocerebrais/complicações , Traumatismo Múltiplo/complicações , Doenças do Nervo Oculomotor/etiologia , Hemorragia Retiniana/etiologia , Atrofia , Toxinas Botulínicas Tipo A/uso terapêutico , Pré-Escolar , Traumatismos Craniocerebrais/fisiopatologia , Lesões por Esmagamento/complicações , Edema/etiologia , Exotropia/tratamento farmacológico , Exotropia/etiologia , Óculos , Feminino , Humanos , Macula Lutea/patologia , Doenças do Nervo Oculomotor/tratamento farmacológico , Doenças do Nervo Óptico/etiologia , Fraturas Orbitárias/etiologia , Retina/diagnóstico por imagem , Tomografia de Coerência Óptica
10.
Physiol Behav ; 122: 72-5, 2013 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-24021924

RESUMO

Given the social and territorial features described in feral cats, it is commonly assumed that life in multi-cat households is stressful for domestic cats and suggested that cats kept as single pets are likely to have better welfare. On the other hand, it has been hypothesized that under high densities cats can organize themselves socially thus preventing stress when spatial dispersion is unavailable. This study was aimed at comparing the general arousal underpinning emotional distress in single housed cats and in cats from multi-cat households (2 and 3-4 cats) on the basis of fecal glucocorticoid metabolites (GCM) measured via enzyme immunoassay (EIA). GCM did not significantly vary as a function of living style (single, double or group-housing); highly stressed individuals were equally likely in the three groups. Young cats in multi-cat households had lower GCM, and overall cats that tolerate (as opposed to dislike) petting by the owners tended to have higher GCM levels. Other environmental aspects within cat houses (e.g. relationship with humans, resource availability) may play a more important role in day to day feline arousal levels than the number of cats per se.


Assuntos
Fezes/química , Glucocorticoides/análise , Glucocorticoides/metabolismo , Comportamento Social , Estresse Psicológico/metabolismo , Animais , Comportamento Animal , Gatos , Personalidade
11.
Cell Immunol ; 162(2): 194-201, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7743546

RESUMO

Secreted proteins are considered to have an important role in inducing resistance to Mycobacterium tuberculosis infection. We analyzed the proliferation of PBMC from five healthy tuberculin-positive individuals, four tuberculosis patients, and six tuberculin-negative healthy controls to the whole bacilli, the 38- and 10-kDa-secreted antigens, and the 65- and 71-kDa hsp. Comparing the proliferative responses between the two mycobacterial-secreted proteins, we have found that both the 38- and the 10-kDa antigens were recognized by PBMC from healthy tuberculin-positive individuals. However, the magnitude of the proliferation caused by the 10-kDa antigen was significantly higher (P < 0.005) than that with the 38-kDa protein. It was a finding of importance that proliferation to the 10-kDa antigen was comparable to that elicited by the whole bacilli. Characterization of proliferative responses toward the 10-kDa antigen demonstrates that human cells process the 10-kDa antigen prior to its recognition by T cells, and that this process might be through lysosomal pathways. These data confirm the strong T cell response against the M. tuberculosis 10-kDa antigen and demonstrate, for the first time, characterization of cellular activation toward this antigen. The magnitude of the proliferative responses to the 65-kDa hsp in the healthy tuberculin-positive subjects compared with tuberculosis patients was not significantly different (P > 0.01). Finally, PBMC from the healthy tuberculin-positive individuals did not recognize the M. tuberculosis 71-kDa hsp. In summary, human resistant cells to tuberculosis respond to different classes of antigens, including constitutive cell wall proteins, secreted antigens, and hsp.


Assuntos
Antígenos de Bactérias/imunologia , Mycobacterium tuberculosis/imunologia , Linfócitos T/imunologia , Tuberculose/imunologia , Feminino , Proteínas de Choque Térmico/imunologia , Humanos , Ativação Linfocitária , Masculino , Proteínas Recombinantes
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