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1.
Med Oral Patol Oral Cir Bucal ; 23(6): e646-e655, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30341273

RESUMO

BACKGROUND: The purpose of this study was to evaluate nanohardness and viscoelastic behavior of dentin surfaces treated with two canal sealer cements for dentin remineralization. MATERIAL AND METHODS: Dentin surfaces were subjected to: i) 37% phosphoric acid (PA) or ii) 0.5 M ethylenediaminetetraacetic acid (EDTA) conditioning prior to the application of two experimental hydroxyapatite-based cements, containing sodium hydroxide (calcypatite) or zinc oxide (oxipatite), respectively. Samples were stored in simulated body fluid during 24 h or 21 d. The intertubular and peritubular dentin were evaluated using a nanoindenter to assess nanohardness (Hi). The load/displacement responses were used for the nano-dynamic mechanical analysis to estimate complex modulus (E*) and tan delta (δ). The modulus mapping was obtained by imposing a quasistatic force setpoint to which a sinusoidal force was superimposed. AFM imaging and FESEM analysis were performed. RESULTS: After 21 d of storage, dentin surfaces treated with EDTA+calcypatite, PA+calcypatite and EDTA+oxipatite showed viscoelastic discrepancies between peritubular and intertubular dentin, meaning a risk for cracking and breakdown of the surface. At both 24 h and 21 d, tan δ values at intertubular dentin treated with the four treatments performed similar. At 21 d time point, intertubular dentin treated with PA+oxipatite achieved the highest complex modulus and nanohardness, i.e., highest resistance to deformation and functional mineralization, among groups. CONCLUSIONS: Intertubular and peritubular dentin treated with PA+oxipatite showed similar values of tan δ after 21 d of storage. This produced a favorable dissipation of energy with minimal energy concentration, preserving the structural integrity at the dentin surface.


Assuntos
Cimentos Dentários/farmacologia , Dentina/efeitos dos fármacos , Hidróxido de Sódio/farmacologia , Remineralização Dentária/métodos , Óxido de Zinco/farmacologia , Humanos , Técnicas In Vitro , Teste de Materiais , Propriedades de Superfície
2.
Int Endod J ; 50 Suppl 2: e109-e119, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28653756

RESUMO

AIM: To evaluate the remineralization ability of two endodontic sealer cements. METHODOLOGY: Mid-coronal dentine surfaces were subjected to: (i) 37% phosphoric acid (PA) or (ii) 0.5 mol L-1 ethylenediaminetetraacetic acid (EDTA) conditioning prior to the application of two experimental hydroxyapatite-based cements, containing sodium hydroxide (calcypatite) or zinc oxide oxiapatite respectively. Samples were stored in simulated body fluid for 24 h or 21 days. Remineralization of the dentine surfaces were studied by Raman spectroscopy (mapping with K-means cluster and hierarchical cluster analysis) was undertaken. Nanoroughness and collagen fibril width measurements were performed with an atomic force microscopy. ANOVA and Student-Newman-Keuls test were performed (α=0.05). RESULTS: Phosphoric acid+oxiapatite promoted both the highest dentine mineralization (P < 0.05) and crystallographic maturity at the dentine surface. Noncrystalline amorphous-like apatites were also formed. Dentine treated with PA+calcypatite attained the roughest surface (P < 0.05) with minimal fibril width (P < 0.05). Cross-linking of collagen only became greater in the group PA+oxiapatite after 21 days. The maximum relative mineral concentration and structure of collagen linked to the amide I and ratio amide III/AGEs was obtained after using PA+calcypatite at 21-days time-point (P < 0.05). EDTA produced a lower stoichiometric hydroxyapatite (P < 0.05) with decreased maturity, at the expense of carbonate band widening, although it favoured the nucleation of carbonated calcium phosphate. CONCLUSIONS: Dentine surfaces treated with PA+oxiapatite attained the highest dentine remineralization with both crystalline-stoichiometric and amorphous apatites, at 21 days. EDTA conditioning facilitated amorphous-bulk mineral precipitation. The amorphization was more intense after using oxiapatite and provided an ion-rich environment favouring in situ dentine remineralization.


Assuntos
Cimentos Dentários/química , Dentina/química , Hidroxiapatitas/química , Óxido de Zinco/química , Teste de Materiais , Ácidos Fosfóricos , Análise Espectral Raman , Propriedades de Superfície , Remineralização Dentária
3.
Clin Psychol Psychother ; 23(2): 183-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25801527

RESUMO

UNLABELLED: The purpose of this study was to adapt the 'Voice and You' Scale (VAY) (Hayward, Denney, Vaughan, & Fowler, 2008) to Spanish and explore its psychometric properties for measuring the perceived relationship with voices. A sample of 50 psychiatric patients with verbal auditory hallucinations (48 had a psychotic disorder and two a borderline personality disorder) was used. Its reliability was calculated using the Cronbach's α and test-retest, and concurrent validity by the Pearson correlation coefficient of the VAY with the Beliefs About Voices Questionnaire and the Psychotic Symptom Rating Scales. The results showed that internal consistency of the Spanish version of the VAY ranged from 0.74 to 0.84 on the various subscales, and test-retest reliability varied from 0.74 to 0.83 on three subscales (voice 'dominance', 'intrusiveness' and hearer 'dependence'), and was lower (0.68) on the hearer 'distance' subscale. Concurrent validity was acceptable as significant associations were found with the Beliefs About Voices Questionnaire and the Psychotic Symptom Rating Scales subscales. It is concluded that the Spanish version of the VAY is a reliable and valid instrument that can assist the exploration of voices within relational frameworks across research and clinical domains. KEY PRACTITIONER MESSAGE: The Spanish version of the VAY is a reliable, valid instrument for evaluating the perception a person can have about his or her relationship with the voices and how the person relates to them. Voices that are perceived as relating dominantly and intrusively, and from whom distance is sought, seem to be distressing and cause disturbance. Voices that are related to dependently are perceived as having benevolent intent and are engaged with. Benevolent or neutral voices may be considered as intrusive because of the intensity and frequency with which they are experienced.


Assuntos
Alucinações/psicologia , Inquéritos e Questionários/normas , Tradução , Adolescente , Adulto , Idoso , Transtorno da Personalidade Borderline/complicações , Transtorno da Personalidade Borderline/psicologia , Feminino , Alucinações/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Psicometria , Transtornos Psicóticos/complicações , Transtornos Psicóticos/psicologia , Reprodutibilidade dos Testes , Espanha , Adulto Jovem
4.
J Popul Econ ; 36(3): 1573-1606, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37223457

RESUMO

Using panel data from India, this paper investigates the effect of early maternal age on offspring human capital, contributing to the scarce evidence on this phenomenon, especially in the context of a developing country. The analysis relies on mother fixed effects to allow for unobserved differences between mothers and employs a variety of empirical strategies to address remaining sibling-specific concerns. Our results indicate that children born to young mothers are shorter for their age, with stronger effects for girls born to very young mothers. We also find some evidence suggesting that children born to very young mothers perform worse in math. By exploring the evolution of effects over time for the first time in the literature, we find that the height effect weakens as children age. Further analysis suggests both biological and behavioral factors as transmission channels. Supplementary Information: The online version contains supplementary material available at 10.1007/s00148-023-00946-0.

6.
Polymers (Basel) ; 13(11)2021 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-34204165

RESUMO

Approximately 200,000 tons of water contaminated with dyes are discharged into effluents annually, which in addition to infectious diseases constitute problems that afflict the population worldwide. This study evaluated the mechanical properties, surface structure, antimicrobial performance, and methylene blue dye-contaminant adsorption using the non-woven fabrics manufactured by melt-blowing. The non-woven fabrics are composed of nylon 6 (Ny 6) and zinc oxide nanoparticles (ZnO NPs). The polymer nanocomposites were previously fabricated using variable frequency ultrasound assisted-melt-extrusion to be used in melt-blowing. Energy dispersion spectroscopy (SEM-EDS) images showed a homogeneous dispersion of the ZnO nanoparticles in nylon 6. The mechanical properties of the composites increased by adding ZnO compared to the nylon 6 matrix, and sample Ny/ZnO 0.5 showed the best mechanical performance. All fabric samples exhibited antimicrobial activity against S. aureus and fungus C. albicans, and the incorporation of ZnO nanoparticles significantly improved this property compared to pure nylon 6. The absorption efficiency of methylene blue (MB), during 60 min, for the samples Ny/ZnO 0.05 and Ny/ZnO 0.25 wt%, were 93% and 65%, respectively. The adsorption equilibrium data obeyed the Langmuir isotherm.

7.
J Phys Condens Matter ; 21(29): 295301, 2009 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-21828529

RESUMO

Different coalescence processes on 1D silver nanostructures synthesized by a PVP assisted reaction in ethylene glycol at 160 °C were studied experimentally and theoretically. Analysis by TEM and HRTEM shows different defects found on the body of these materials, suggesting that they were induced by previous coalescence processes in the synthesis stage. TEM observations showed that irradiation with the electron beam eliminates the boundaries formed near the edges of the structures, suggesting that this process can be carried out by the application of other means of energy (i.e. thermal). These results were also confirmed by theoretical calculations by Monte Carlo simulations using a Sutton-Chen potential. A theoretical study by molecular dynamics simulation of the different coalescence processes on 1D silver nanostructures is presented, showing a surface energy driven sequence followed to form the final coalesced structure. Calculations were made at 1000-1300 K, which is near the melting temperature of silver (1234 K). Based on these results, it is proposed that 1D nanostructures can grow through a secondary mechanism based on coalescence, without losing their dimensionality.

8.
Arch Soc Esp Oftalmol ; 84(5): 267-70, 2009 May.
Artigo em Espanhol | MEDLINE | ID: mdl-19466689

RESUMO

CLINICAL CASE: A 69-year-old woman developed choroidal metastasis from a breast carcinoma 2 years after the initial diagnosis, surgery and chemotherapy. After treatment with palliative chemotherapy and external radiotherapy, we used fluorescein angiography (FA) and optical coherence tomography (OCT) to evaluate the resolution of the serous retinal detachment, as well as a later relapse in the optic nerve. DISCUSSION: OCT is useful in the follow-up of choroidal metastasis after treatment. However, OCT imaging is limited by the initial choroidal location of metastasis. The autofluorescence can detect exudative tumoral activity even without obvious changes in OCT or FA.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/secundário , Neoplasias da Coroide/secundário , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/complicações , Carcinoma Ductal de Mama/diagnóstico , Carcinoma Ductal de Mama/tratamento farmacológico , Carcinoma Ductal de Mama/radioterapia , Neoplasias da Coroide/complicações , Neoplasias da Coroide/diagnóstico , Neoplasias da Coroide/tratamento farmacológico , Neoplasias da Coroide/radioterapia , Terapia Combinada , Ciclofosfamida/administração & dosagem , Ciclofosfamida/análogos & derivados , Doxorrubicina/administração & dosagem , Feminino , Angiofluoresceinografia , Fluoruracila/administração & dosagem , Humanos , Excisão de Linfonodo , Mastectomia Radical , Neoplasias do Nervo Óptico/secundário , Cuidados Paliativos , Descolamento Retiniano/etiologia , Tomografia de Coerência Óptica
9.
Polymers (Basel) ; 11(7)2019 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-31330943

RESUMO

The study of polymeric nanocomposites is a possible alternative to conventional flame retardants. The aim of the present work is to investigate the effects of carbon-nanotubes (CNT) and TiO2 nanoparticles (NPs) on the thermo-mechanical, flammability, and electrical properties of polypropylene (PP). In this work, PP-TiO2/CNT nanocomposites were obtained with TiO2/CNT mixtures (ratio 1:2) through the melt extrusion process, with different weight percentage of nanoparticles (1, 5, and 10 wt %). The PP-TiO2/CNT nanocomposites were characterized by DSC, TGA, MFI, FTIR, XRD, and SEM. It was possible to determine that the thermal stability of the PP increases when increasing the content of NPs. A contrary situation is observed in the degree of crystallinity and thermo-oxidative degradation, which decreased with respect to pure PP. The TiO2 NPs undergo coalition and increase their size at a lower viscosity of the nanocomposite (1 and 5 wt %). The mechanical properties decreased slightly, however, the Young's modulus presented an improvement of 10% as well as electrical conductivity, this behavior was noted in nanocomposites of 10 wt % of NPs. Flammability properties were measured with a cone calorimeter, and a reduction in the peak heat release rate was observed in nanocomposites with contents of nanoparticles of 5 and 10 wt.

10.
Nanomaterials (Basel) ; 9(9)2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31491904

RESUMO

Chronic kidney disease (CKD) is a worldwide public health problem. In stages III and IV of CKD, uremic toxins must be removed from the patient by absorption, through a treatment commonly called hemodialysis. Aiming to improve the absorption of uremic toxins, we have studied its absorption in chemically modified graphene nanoplatelets (GNPs). This study involved the reaction between GNPs and diamines with reaction times of 30, 45 and 60 min using ultrasound waves of different amplitudes and frequencies. Functionalized GNPs were analyzed by Fourier Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), Scanning electron microscopy and energy dispersitive spectroscopy (SEM-EDS), and Thermogravimetric analysis (TGA). The analysis of the functional groups confirmed the presence of amide and hydroxyl groups on the surface of the GNPs by reactions of diamines with carboxylic acids and epoxides. Adsorption of uremic toxins was determined using equilibrium isotherms, where the maximum percentage of removal of uremic toxins was 97%. Dispersion of modified graphene nanoplatelets was evaluated in water, ethanol and hexane, as a result of this treatment was achieved a good and effective dispersion of diamines-modified graphene nanoplatelets in ethanol and hexane. Finally, the results of hemolysis assays of the modified graphene with amine demonstrated that it was not cytotoxic when using 500 mg/mL. The samples of modified graphene demonstrated low degree of hemolysis (<2%), so this material can be used for in vivo applications such as hemodialysis.

11.
J Neurosci Res ; 86(8): 1871-83, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18241054

RESUMO

The antigen recognized by the monoclonal antibody 3CB2 (3CB2-Ag and 3CB2 mAb) is expressed by radial glia and astrocytes in the developing and adult vertebrate central nervous system (CNS) of vertebrates as well as in neural stem cells. Here we identified the 3CB2-Ag as vimentin by proteomic analysis of human glial cell line U-87 extracts (derived from a malignant astrocytoma). Indeed, the 3CB2 mAb recognized three vimentin isoforms in glial cell lines. In the human retina, 3CB2-Ag was expressed in Müller cells, astrocytes, some blood vessels, and cells in the horizontal cell layer, as determined by immunoprecipitation and immunofluorescence. Three populations of astrocytes were distinguishable by double-labeling immunohistochemistry: vimentin+/GFAP+, vimentin-/GFAP+, and vimentin+/GFAP-. Hence, we conclude that 1) the 3CB2-Ag is vimentin; 2) vimentin isoforms are differentially expressed in normal and transformed astrocytes; 3) human retinal astrocytes display molecular heterogeneity; and 4) the 3CB2 mAb is a valuable tool to study vimentin expression and its function in the human retina.


Assuntos
Anticorpos Monoclonais/biossíntese , Regulação da Expressão Gênica/fisiologia , Retina/metabolismo , Vimentina/biossíntese , Adolescente , Adulto , Animais , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/metabolismo , Astrócitos/metabolismo , Astrocitoma/metabolismo , Astrocitoma/patologia , Linhagem Celular Transformada , Linhagem Celular Tumoral , Humanos , Pessoa de Meia-Idade , Neuroglia/metabolismo , Neuroglia/patologia , Isoformas de Proteínas/biossíntese , Isoformas de Proteínas/genética , Isoformas de Proteínas/imunologia , Ratos , Retina/imunologia , Vimentina/genética , Vimentina/imunologia
12.
Arch Soc Esp Oftalmol ; 83(3): 193-6, 2008 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-18311679

RESUMO

CLINICAL CASE: This report is based on the case of a 35-year-old woman who developed a combined hamartoma of the retina and retinal pigment epithelium in her right eye. The diagnosis was determined based on the fundus examination: hyperplasia of the retinal pigment epithelium cells, tortuosity of the vessels and epiretinal membrane. DISCUSSION: Optical coherence tomography and retinal angiography are important to rule out malignant melanoma of the choroid and retinoblastoma. Regular follow-up is essential because reduction in visual acuity can be related to an epiretinal membrane, neovascular membrane or vitreous hemorrhage.


Assuntos
Hamartoma/diagnóstico por imagem , Hamartoma/patologia , Epitélio Pigmentado Ocular , Doenças Retinianas/diagnóstico por imagem , Doenças Retinianas/patologia , Tomografia de Coerência Óptica , Adulto , Angiografia , Feminino , Humanos
13.
Br J Clin Psychol ; 45(Pt 3): 309-17, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17147098

RESUMO

OBJECTIVES: This study examines the relationship between a predisposition to hallucinations and meta-cognitive variables and thought-control techniques, controlling for the possible effect of anxiety. In order to do so, we start out with the hypothesis that anxiety does not, in itself, explain the association between meta-cognitions and a predisposition to auditory and visual hallucinations. DESIGN: A within-participants correlational design was employed. METHODS: Four psychometric tests relating to predisposition to hallucinations, anxiety, meta-cognitions and thought-control techniques were administered to 150 participants. RESULTS: It was found that, after controlling for participants' anxiety levels, the 'loss of cognitive confidence' factor predicted the score on the scale of predisposition to both auditory and visual hallucinations. Thought-control strategies based on worry were also found to be predictive of a greater predisposition to hallucinations, regardless of whether or not participants' anxiety level was controlled. CONCLUSIONS: Meta-cognitive variables of cognitive confidence and thought control through worry are positively associated with a predisposition to hallucinations. LIMITATIONS: The correlational nature of the design does not allow inferences about causal relationships.


Assuntos
Ansiedade/psicologia , Cognição , Cultura , Alucinações/psicologia , Inibição Psicológica , Pensamento , Adulto , Conscientização , Feminino , Humanos , Masculino , Inventário de Personalidade/estatística & dados numéricos , Psicometria , Teste de Realidade , Reprodutibilidade dos Testes , Enquadramento Psicológico , Superstições , Inquéritos e Questionários
14.
Arch Soc Esp Oftalmol ; 81(2): 93-100, 2006 Feb.
Artigo em Espanhol | MEDLINE | ID: mdl-16511716

RESUMO

PURPOSE: To examine the short- and medium-term intraocular pressure (IOP) lowering effects of combined phacoemulsification and non-penetrating deep sclerectomy without the use of scleral implant or antifibrotics in open-angle glaucoma (primary and pseudoexfoliative) and coexisting cataract in eyes with no known risk factors for bleb failure. METHODS: Retrospective study of 15 eyes of 12 patients with medically uncontrolled open-angle glaucoma or open-angle glaucoma treated with two or more drugs and coexisting cataract with no known risk factors for glaucoma surgery failure. All patients received combined phacoemulsification and non-penetrating deep sclerectomy without scleral implant or antifibrotics performed by the same surgeon. Nd-YAG perforation of the trabeculodescemetic membrane and/or needling with mitomycin-C was performed postoperatively for IOP control. Main outcome measures were postoperative IOP, percentage of eyes with IOP < 17 mmHg, complications and final visual acuity (VA). Median follow-up was 12.0 months (SD: 0.6) and ranged from 1 to 30 months. RESULTS: Mean preoperative IOP with medical treatment was 21.80 mmHg (SD: 5.14) and decreased to 14.42 mmHg (SD: 2.15) at 12-month visit. Mean antiglaucoma medication preoperative was 1.93 (SD: 0.70) and was reduced to 0.13 (DE: 0.35) postoperative. At 12-month visit, 80% had an IOP lower than 17 mmHg with a mean VA gain of 2.50 Snellen lines. Conjuntival wound leakage was the most frequent complication (20%; 3/15). CONCLUSIONS: Primary combined phacoemulsification and non-penetrating deep sclerectomy without collagen implant or antifibrotics in primary open-angle glaucoma with coexisting cataract, significantly lowers IOP in the short- and medium term in low-risk cases for glaucoma surgery failure, allowing for rapid visual improvement with a low complication rate.


Assuntos
Glaucoma de Ângulo Aberto/cirurgia , Pressão Intraocular , Facoemulsificação , Esclera/cirurgia , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Feminino , Humanos , Masculino , Fatores de Tempo
15.
Sci Rep ; 6: 35507, 2016 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-27759113

RESUMO

The complementarity of historical and contemporary processes contributes to understanding the genetic structure of continuously distributed marine species with high dispersal capabilities. Cephalorhynchus eutropia, has a continuous coastal distribution with strong genetic differentiation identified by nuclear DNA markers. We explored the historical dimension of this genetic differentiation between northern and southern populations to evaluate phylogeographic structure. Additionally, we conducted mtDNA and microsatellite analyses to detect past and recent demographic changes. The southern population was characterized by lower genetic diversity with a signal of population expansion, likely associated with ice retreat and habitat extension after the Last Glacial Maximum (LGM). In contrast, structure within the northern population was more consistent with stable historical population size. Approximate Bayesian Computation analyses suggested that during the LGM, C. eutropia persisted in the northern area; while the south was colonized by dispersal ~11,000 years ago followed by population expansion. This study shows that Chilean dolphin population structure is consistent with predictions from the Expansion-Contraction biogeographic model, with a poleward post-glacial shift revealed in current genetic structure. The results also confirm the validity of the population units previously identified, demonstrating their historical origin and highlighting the utility of integrating genetic markers with different temporal scale resolutions.


Assuntos
DNA Mitocondrial/genética , Golfinhos/genética , Ecossistema , Repetições de Microssatélites/genética , Modelos Biológicos , Animais , Chile , Evolução Molecular , Especiação Genética , Variação Genética , Genética Populacional , Periodicidade , Filogenia , Filogeografia
16.
J Phys Chem B ; 109(37): 17488-95, 2005 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-16853236

RESUMO

Graphite-filled MoS2 nanotubes were synthesized by pyrolizing propylene inside MoS2 nanotubes prepared by a template-assisted technique. The large coaxial nanotubes were constituted of graphite sheets inserted between the MoS2 layers, forming the outer part, and coaxial multiwall carbon nanotubes intercalated with MoS2 inside. High-resolution electron microscopy (HREM) and electron energy loss spectroscopy techniques along with molecular dynamics simulation and quantum mechanical calculations were used to characterize the samples. The one-dimensional structures exhibit diverse morphologies such as long straight and twisted nanotubes with several structural irregularities. The interplanar spacing between the MoS2 layers was found to increase from 6.3 to 7.4 A due to intercalation with carbon. Simulated HREM images revealed the presence of mechanical strains in the carbon-intercalated MoS2 layers as the reason for obtaining these twisted nanostructures. The mechanism of formation of carbon-intercalated MoS2 tubular structures and their stability and electronic properties are discussed. Our results open up the possibility of using MoS2 nanotubes as templates for the synthesis of new one-dimensional binary-phase systems.

17.
Arch Soc Esp Oftalmol ; 80(1): 41-4, 2005 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-15692893

RESUMO

CLINICAL CASE: A 37 year old female with histologically proven Kikuchi-Fujimoto disease is presented. She developed panuveitis, vasculitis and subretinal macular infiltrate, probably as a recurrence of the disease. Immunosuppressive treatment (methotrexate) was initiated in the absence of response to systemic steroid therapy and threat to vision owing to macular involvement. DISCUSSION: Ophthalmic complications of Kikuchi-Fujimoto disease are unusual. We discuss differential diagnosis and emphasize the aggresiveness of our case.


Assuntos
Linfadenite Histiocítica Necrosante/complicações , Pan-Uveíte/etiologia , Adulto , Antimetabólitos Antineoplásicos/uso terapêutico , Eletrorretinografia , Feminino , Angiofluoresceinografia , Fundo de Olho , Glucocorticoides/uso terapêutico , Linfadenite Histiocítica Necrosante/diagnóstico , Humanos , Metotrexato/uso terapêutico , Pan-Uveíte/diagnóstico , Pan-Uveíte/tratamento farmacológico , Vasculite Retiniana/diagnóstico , Vasculite Retiniana/tratamento farmacológico , Vasculite Retiniana/etiologia , Resultado do Tratamento , Acuidade Visual
18.
Eur J Cell Biol ; 78(9): 614-23, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10535303

RESUMO

Endoglin is the gene mutated in hereditary hemorrhagic telangiectasia type 1 (HHT1), a dominantly inherited vascular disorder. Endoglin glycoprotein is a component of the transforming growth factor type beta (TGF-beta) receptor system which is highly expressed by endothelial cells, and at lower levels on fibroblasts and smooth muscle cells, suggesting the involvement of these lineages in the HHT1 vascular dysplasia. Overexpression of endoglin in mouse NCTC929 fibroblasts led to decreased migration in chemotactic and wound healing assays, as well as changes in the cellular morphology. When plated on uncoated surfaces, endoglin transfectants formed intercellular clusters, endoglin being not specifically localized to the cell-cell junctions, but homogenously distributed on the cellular surface. Although the expression of alpha5beta1 integrin and of an activation epitope of beta1 integrin were unchanged, a polyclonal antibody to alpha5beta1 integrin was able to inhibit cluster formation, suggesting the involvement of integrin ligand/s. In fact, coating with fibronectin, laminin, or an RGD-containing 80 kDa fragment of fibronectin were able to prevent the cellular clustering. Furthermore, synthesis of plasminogen activator inhibitor 1 (PAI-1), and to a weak extent that of fibronectin, were inhibited in endoglin transfectants. Thus, the presence of endoglin in mouse NCTC929 fibroblasts is associated with reduced production of certain extracellular matrix (ECM) components, which might explain their altered morphology, migration and intercellular cluster formation.


Assuntos
Adesão Celular , Movimento Celular , Fibroblastos/metabolismo , Molécula 1 de Adesão de Célula Vascular/metabolismo , Molécula 1 de Adesão de Célula Vascular/fisiologia , Animais , Antígenos CD , Colágeno/metabolismo , Endoglina , Citometria de Fluxo , Humanos , Laminina/metabolismo , Camundongos , Microscopia Confocal , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Receptores de Superfície Celular , Receptores de Fibronectina/metabolismo , Transfecção , Cicatrização
19.
Biochem Pharmacol ; 60(3): 371-9, 2000 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-10856432

RESUMO

We analyzed both the cytotoxicity and the type of cell death produced by the novel binuclear Pt(III) compound Pt-Spym ([Pt(2)(2-mercaptopyrimidine)(4)Cl(2)]) in kidney human fibroblasts and in human tumor cell lines (HeLa, CH1, CH1cisR and HL-60). The data showed that Pt-Spym displayed higher cytotoxicity against these tumor cells than cisplatin. In contrast, Pt-Spym had low toxicity against normal human fibroblasts. Interestingly, Pt-Spym circumvented cisplatin resistance in CH1cisR cells. We also observed that Pt-Spym induced the characteristic changes attributed to apoptosis in cells with normal levels of p53 protein (CH1 and CH1cisR) and with low levels of p53 protein (HeLa), but not in cells lacking p53 (HL-60). Interestingly, Western blot data indicated that apoptosis induction by Pt-Spym in HeLa, CH1, and CH1cisR cells was not associated with drastic changes in p53 levels. However, cis-DDP strongly decreased p53 levels in CH1 and CH1cisR cells and abolish p53 protein in HeLa cells. Altogether, these results suggest that induction of apoptosis by Pt-Spym requires the presence of p53 protein.


Assuntos
Antineoplásicos/farmacologia , Apoptose , Compostos Organoplatínicos/farmacologia , Compostos de Platina/farmacologia , Pirimidinas/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Anexinas/farmacologia , Núcleo Celular/efeitos dos fármacos , Tamanho Celular/efeitos dos fármacos , Células Cultivadas , Fragmentação do DNA/efeitos dos fármacos , Eletroforese em Gel de Ágar , Células HL-60 , Células HeLa , Humanos
20.
Obstet Gynecol ; 89(1): 19-23, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8990430

RESUMO

OBJECTIVE: To establish the indications for surgical intervention, at the appropriate gestational duration, for brain tumors in pregnant women, and to evaluate any association pregnancy hormones may have with the rate of growth or development of complications of brain tumors. METHODS: We observed seven women with brain tumors associated with pregnancy in a series of 126,413 pregnancies from 1983 to 1995. One woman presented with symptoms of intracranial hypertension, and neurologic signs were the first symptoms in two other women. One woman presented with a sudden hemorrhagic lesion, and three had focal seizures. All were evaluated with computed tomography, magnetic resonance imaging, or both. RESULTS: Six of the seven women had surgery; the seventh was treated with radiotherapy because the neuroradiologic studies suggested a quickly growing brainstem glioma. Diagnoses were confirmed on histology in six women: two with meningiomas, two with ependymomas, and two with low-grade astrocytomas (one of these had multiple astrocytomas). Estrogen and progesterone receptors were studied in two cases (one meningioma and one astrocytoma) and were present in both. CONCLUSION: Management of brain tumors should be tailored to the individual patient. There may be a relation between pregnancy hormones and the rate of brain tumor growth mediated through specific intracellular receptors.


Assuntos
Neoplasias Encefálicas , Complicações Neoplásicas na Gravidez , Adulto , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/cirurgia , Feminino , Humanos , Gravidez , Complicações Neoplásicas na Gravidez/diagnóstico , Complicações Neoplásicas na Gravidez/cirurgia
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