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1.
J Phys Condens Matter ; 31(27): 275804, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-30952140

RESUMO

We investigate the influence of the magnon-phonon relaxation processes in the magnon transport under thermal gradient in the ferrimagnetic insulator yttrium iron garnet (YIG). Based on the Boltzmann equation we calculate the magnon contribution in the thermal conductivity in YIG and the longitudinal spin Seebeck effect in YIG/Pt films, including the influence of the magnon relaxation to the lattice through a phenomenological damping parameter. Our results are in good agreement with reported experimental data showing that besides the magnon-magnon relaxation processes, the magnon-phonon relaxation plays an important role in the thermal properties in YIG films.

2.
Parasite Immunol ; 40(4): e12519, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29380393

RESUMO

Manipulation of costimulatory and surface molecules that shape the extent of immune responses by Leishmania is suggested as one of the mechanisms of evading the host's defences. The experiments reported here were designed to evaluate the expressions of CD11b, CD11c, CD14, CD18, CD54, CD80, CD86, CD206, MHC class II and TLR-2 (Toll-like receptor 2) in human macrophages infected with L. amazonensis. Phenotypic evaluation revealed a negative modulation in CD11b, CD11c, CD14, CD18, CD54 and MHC class II molecules, depending on the level of infection. The results showed that as early as 1 hour after infection no reduction in marker expression occurs, whereas after 24 hours, downregulation of these molecules was observed in macrophages. No significant changes were observed in the expressions of CD80, CD86, CD206 and TLR2. Evidence of the differential modulation of markers expression and that after parasite uptake no reduction in surface marker expression occurs indicates that parasite internalization is not involved in the phenomena of down-modulation.


Assuntos
Antígenos CD/biossíntese , Leishmania mexicana/imunologia , Leishmaniose Cutânea/imunologia , Macrófagos/imunologia , Macrófagos/parasitologia , Adulto , Animais , Antígenos CD/imunologia , Antígenos de Superfície/biossíntese , Antígenos de Superfície/imunologia , Antígeno B7-1/biossíntese , Antígeno CD11b/biossíntese , Células Cultivadas , Antígenos de Histocompatibilidade Classe II/biossíntese , Humanos , Leishmaniose Cutânea/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Receptor 2 Toll-Like/biossíntese
3.
Photochem Photobiol Sci ; 16(2): 238-245, 2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-28009887

RESUMO

Crepis japonica (L.) D.C. (Asteraceae), a weed with antioxidant, antiallergenic, antiviral and antitumor properties displays both medicinal properties and nutritional value. This study aims to assess the effects of a supplementation of blue light and UV-A radiation on the growth, leaf anatomical structure and phenolic profile of the aerial parts of Crepis japonica. Plants were grown under two light treatments: W (control - white light), W + B (white light supplemented with blue light) and W + UV-A (white light supplemented with UV-A radiation). We recorded the length, width, and weight of fresh and dry leaves, the thickness of the epidermis and mesophyll, and stomata density. The phenolic profiles of the aqueous extracts of the aerial parts were analyzed by HPLC-DAD. There was an increase in the leaf size, stomatal density, and phenolic production, and a thickening of the mesophyll and epidermis. UV-A radiation increased the phenolic production more than blue light. Blue light and UV-A radiation both improved the production of caffeic acid by about 6 and 3 times, respectively, in comparison to control. This compound was first reported as a constituent of the extract from the aerial parts together with caftaric acid. UV-A also promoted the production of chlorogenic acid (about 1.5 times in comparison to the control). We observed that the morphological and chemical parameters of C. japonica are modified in response to blue light and UV-A radiation, which can be used as tools in the cultivation of this species in order to improve its medicinal properties and nutritional value.


Assuntos
Crepis/efeitos da radiação , Luz , Raios Ultravioleta , Ácido Clorogênico/química , Ácido Clorogênico/isolamento & purificação , Ácido Clorogênico/metabolismo , Cromatografia Líquida de Alta Pressão , Crepis/química , Crepis/metabolismo , Fenóis/química , Fenóis/isolamento & purificação , Fenóis/metabolismo , Componentes Aéreos da Planta/química , Componentes Aéreos da Planta/metabolismo , Extratos Vegetais/análise , Extratos Vegetais/química , Folhas de Planta/química , Folhas de Planta/metabolismo , Folhas de Planta/efeitos da radiação
4.
Clin Otolaryngol ; 42(2): 268-274, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27455393

RESUMO

OBJECTIVE: Endoscopic procedures are becoming common in middle ear surgery. Inflammation due to chronic ear disease can cause bony erosion of the carotid artery and Fallopian canals, making them more vulnerable during surgery. The objective of this study was to determine whether or not chronic ear disease increases dehiscence of the carotid artery and Fallopian canals. DESIGN: Comparative human temporal bone study. SETTING: Otopathology laboratory. PARTICIPANTS: We selected 78 temporal bones from 55 deceased donors with chronic otitis media or cholesteatoma and then compared those two groups with a control group of 27 temporal bones from 19 deceased donors with no middle ear disease. MAIN OUTCOME MEASURES: We analysed the middle ear, carotid artery canal and Fallopian canal, looking for signs of dehiscence of its bony coverage, using light microscopy. RESULTS: We found an increased incidence in dehiscence of the carotid artery and Fallopian canals in temporal bones with chronic middle ear disease. The size of the carotid artery canal dehiscence was larger in the middle ear-diseased groups, and its bony coverage, when present, was also thinner compared to the control group. Dehiscence of the carotid artery canal was more frequently located closer to the promontory. The incidence of Fallopian canal dehiscence was significantly higher in temporal bones from donors older than 18 years with chronic middle ear disease. CONCLUSION: The increased incidence of the carotid artery and Fallopian canal dehiscence in temporal bones with chronic middle ear disease elevates the risk of adverse events during middle ear surgery.


Assuntos
Doenças Ósseas/patologia , Artérias Carótidas/patologia , Colesteatoma da Orelha Média/patologia , Endoscopia , Otite Média/patologia , Osso Temporal/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Ósseas/cirurgia , Cadáver , Criança , Colesteatoma da Orelha Média/cirurgia , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Otite Média/cirurgia
5.
Mol Cytogenet ; 9: 20, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26913079

RESUMO

BACKGROUND: Wilms tumor (WT) has a not completely elucidated pathogenesis. DNA copy number alterations (CNAs) are common in cancer, and often define key pathogenic events. The aim of this work was to investigate CNAs in order to disclose new candidate genes for Wilms tumorigenesis. RESULTS: Array-CGH of 50 primary WTs without pre-chemotherapy revealed a few recurrent CNAs not previously reported, such as 7q and 20q gains, and 7p loss. Genomic amplifications were exclusively detected in 3 cases of WTs that later relapsed, which also exhibited an increased frequency of gains affecting a 16.2 Mb 1q21.1-q23.2 region, losses at 11p, 11q distal, and 16q, and WT1 deletions. Conversely, aneuploidies of chromosomes 13 and 19 were found only in WTs without further relapse. The 1q21.1-q23.2 gain associated with WT relapse harbours genes such as CHD1L, CRABP2, GJA8, MEX3A and MLLT11 that were found to be over-expressed in WTs. In addition, down-regulation of genes encompassed by focal deletions highlighted new potential tumor suppressors such as CNKSR1, MAN1C1, PAQR7 (1p36), TWIST1, SOSTDC1 (7p14.1-p12.2), BBOX and FIBIN (11p13), and PLCG2 (16q). CONCLUSION: This study confirmed the presence of CNAs previously related to WT and characterized new CNAs found only in few cases. The later were found in higher frequency in relapsed cases, suggesting that they could be associated with WT progression.

6.
Phytomedicine ; 19(2): 115-21, 2012 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-21802918

RESUMO

Aqueous extract of Kalanchoe pinnata (Kp) have been found effective in models to reduce acute anaphylactic reactions. In the present study, we investigate the effect of Kp and the flavonoid quercetin (QE) and quercitrin (QI) on mast cell activation in vitro and in a model of allergic airway disease in vivo. Treatment with Kp and QE in vitro inhibited degranulation and cytokine production of bone marrow-derived mast cells following IgE/FcɛRI crosslinking, whereas treatment with QI had no effect. Similarly, in vivo treatment with Kp and QE decreased development of airway hyperresponsiveness, airway inflammation, goblet cell metaplasia and production of IL-5, IL-13 and TNF. In contrast, treatment with QI had no effect on these parameters. These findings demonstrate that treatment with Kp or QE is effective in treatment of allergic airway disease, providing new insights to the immunomodulatory functions of this plant.


Assuntos
Hiper-Reatividade Brônquica/tratamento farmacológico , Kalanchoe/química , Mastócitos/efeitos dos fármacos , Fitoterapia , Quercetina/análogos & derivados , Animais , Teste de Degranulação de Basófilos , Hiper-Reatividade Brônquica/imunologia , Hiper-Reatividade Brônquica/prevenção & controle , Células Caliciformes/efeitos dos fármacos , Células Caliciformes/imunologia , Interleucina-13/imunologia , Interleucina-5/imunologia , Kalanchoe/imunologia , Mastócitos/imunologia , Metaplasia/tratamento farmacológico , Metaplasia/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/administração & dosagem , Ovalbumina/imunologia , Extratos Vegetais/química , Quercetina/imunologia , Quercetina/isolamento & purificação , Quercetina/farmacologia , Fator de Necrose Tumoral alfa/imunologia
7.
Int J Antimicrob Agents ; 36(6): 557-61, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20889313

RESUMO

Meticillin-resistant Staphylococcus aureus (MRSA) is a major nosocomial bacterium for which prevention and control measures consist mainly of the application of biocides with antiseptic and disinfectant activity. In this study, we demonstrated the presence of the plasmid-located efflux pump gene qacA in MRSA strain HPV107, a clinical isolate representative of the MRSA Iberian clone. The existence of efflux activity in strain HPV107 due to the QacA pump was also established and this QacA efflux activity was linked with a phenotype of reduced susceptibility towards several biocide compounds. No association could be made with antibiotic resistance. This work emphasises the potential of QacA pump activity in the maintenance and dissemination of important MRSA strains in the hospital setting and, increasingly, in the community.


Assuntos
Proteínas de Bactérias/genética , Desinfetantes/farmacologia , Proteínas de Membrana Transportadoras/genética , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/genética , Plasmídeos , Infecções Estafilocócicas/microbiologia , DNA Bacteriano/genética , Humanos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Portugal
8.
Mol Syndromol ; 1(3): 133-135, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21031083

RESUMO

We report on a patient with NF1 microdeletion and clinical manifestations that fulfill the diagnostic criteria for neurofibromatosis type 1 but also presenting features reminiscent of Proteus syndrome.

9.
Antivir Chem Chemother ; 13(4): 219-21, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12495209

RESUMO

This work evaluated the effect of a sulphated fucan extracted from the Laminaria abyssalis marine algae on the human T cell lymphotropic virus type 1 (HTLV-1)-induced syncytium formation. The experiments were carried out in HeLa cells cocultured with a HTLV-1-infected T cell line (C91/PL cells) in the presence of the sulphated polysaccharide at concentration below that corresponding to the ED50. The sulphated fucan inhibited almost 100% of the syncytium formation at concentration of 100 microg/mI and was still active (>95%) at a concentration of 25 microg/ml. It was also observed that the best inhibition occurred when the compound was added in the first 2 h of the cell-to-cell contact. This is the first report showing that a purified sulphated polysaccharide, extracted from marine algae, is able to inhibit the cell-to-cell contact essential for the spreading of the HTLV-1.


Assuntos
Células Gigantes/efeitos dos fármacos , Vírus Linfotrópico T Tipo 1 Humano/efeitos dos fármacos , Laminaria/química , Polissacarídeos/farmacologia , Comunicação Celular/efeitos dos fármacos , Comunicação Celular/fisiologia , Sulfato de Dextrana/farmacologia , Células Gigantes/virologia , Infecções por HTLV-I/virologia , Células HeLa , Vírus Linfotrópico T Tipo 1 Humano/fisiologia , Humanos , Linfócitos T/virologia , Fatores de Tempo , Células Tumorais Cultivadas
10.
Planta Med ; 66(2): 134-7, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10763586

RESUMO

Previously we demonstrated that Kalanchoe pinnata (KP) leaf extracts inhibited in vitro lymphocyte proliferation and showed in vivo immunosuppressive activity. Here we attempt to identify the immunosuppressive substances present in KP guided by the lymphoproliferative assays. From the ethanolic extract was purified a fraction (KP12SA) twenty-fold more potent to block murine lymphocyte proliferation than the crude extract. Chemical analysis by 1H- and 13C-NMR, IR and GC-MS of KP12SA (methylated sample) showed 89.3% of palmitic acid (C16), 10.7% of stearic acid (C18) and traces of arachidic (C20) and behenic acids (C22). This study provides evidence that fatty acids present in Kalanchoe pinnata may be responsible, at least in part, for its immunosuppressive effect in vivo.


Assuntos
Ácidos Graxos/farmacologia , Imunossupressores/farmacologia , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Linfócitos T/efeitos dos fármacos , Animais , Divisão Celular/efeitos dos fármacos , Ácidos Graxos/isolamento & purificação , Camundongos , Camundongos Endogâmicos BALB C , Linfócitos T/citologia
11.
Otolaryngol Clin North Am ; 32(3): 413-41, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10393777

RESUMO

The flexible approach to tympanoplasty has been found to be adaptable to various forms of pathologic conditions found in the temporal bone, including inflammation and infection, congenital stenosis, benign and malignant tumors, and traumatic injuries. This approach finds its best indication among all pathologic conditions in the temporal bone, in the surgical treatment of otitis media, and its sequelae. A procedure conceived to treat this dynamic process must be adaptable to new circumstances and new findings and be ready to manage unexpected situations. The flexible tympanoplasty is a step-wise approach designed to explore the contents of the middle ear methodically and in the process disclose, confirm, and often treat disease.


Assuntos
Transtornos da Audição/etiologia , Otite Média Supurativa , Timpanoplastia/métodos , Criança , Pré-Escolar , Doença Crônica , Transtornos da Audição/diagnóstico , Humanos , Lactente , Otite Média Supurativa/complicações , Otite Média Supurativa/diagnóstico , Otite Média Supurativa/cirurgia , Cuidados Pós-Operatórios , Cuidados Pré-Operatórios , Perfuração da Membrana Timpânica/etiologia , Perfuração da Membrana Timpânica/cirurgia
12.
Am J Med Genet ; 84(3): 204-7, 1999 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-10331592

RESUMO

In order to investigate the origin of the fragile X mutation in the Brazilian population, we assessed the size of the microsatellite markers DXS548, FRAXAC1 and FRAXAC2 in 72 X chromosomes from unrelated affected males and 64 control chromosomes. We found a significantly different distribution of alleles between fragile X and controls for loci DXS548 and FRAXAC1, but no apparent linkage disequilibrium was detected for the sequence FRAXAC2. The most frequent DXS548/FRAXAC1 haplotypes in affected males were haplotypes 204/158 bp (2-1) and 196/152 bp (6-4). These findings are in accordance with the proposed two main mutational pathways for the generation of FMR-1 alleles that predispose to instability and hyperexpansion.


Assuntos
Síndrome do Cromossomo X Frágil/genética , Cromossomo X/genética , Alelos , Brasil , Genética Populacional , Haplótipos , Humanos , Masculino , Reação em Cadeia da Polimerase
13.
Eur Arch Otorhinolaryngol ; 255(4): 189-94, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9592676

RESUMO

Significant anatomical variations within the middle ear are described as well as atypical histopathological findings in 13 selected human temporal bones. Bones studied included such vascular and bony abnormalities as carotid artery canal dehiscence, a high jugular bulb, persistent stapedial artery and facial nerve canal dehiscences. Bones also included obliterative otosclerosis, malleus head fixation and a variety of chronic inflammatory changes and/or sequelae. Those features considered to render cases prone to complications are detailed.


Assuntos
Orelha Média/anormalidades , Complicações Intraoperatórias/cirurgia , Timpanoplastia , Orelha Média/patologia , Orelha Média/cirurgia , Humanos , Complicações Intraoperatórias/patologia , Fatores de Risco
14.
Laryngoscope ; 102(11): 1229-36, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1405982

RESUMO

Chronic suppurative otitis media has been clinically defined as a chronic discharge from the middle ear in the presence of a perforation of the tympanic membrane. However, irreversible tissue pathology in the middle ear or mastoid can occur behind an intact tympanic membrane. One hundred forty-four human temporal bones with chronic otitis media were divided into two groups: those with perforated (28) and those with nonperforated (116) tympanic membranes. The histopathological findings of their middle ears were compared. Granulation tissue in various degrees was the most prominent pathological feature. It was observed in 96% of temporal bones with perforation of the tympanic membrane, and in 97% of those without perforation. Also found were ossicular bony changes (96% with perforation; 90.5% without), middle ear effusion (93% with perforation; 89% without), cholesterol granuloma (21% with perforation; 12% without), cholesteatoma (36% with perforation; 4% without), and tympanosclerosis (43% with perforation; 20% without). This study shows that the histopathological changes of the middle ear are similar in temporal bones with and without perforation of the tympanic membrane. The clinician should, therefore, be aware that an intact tympanic membrane does not necessarily preclude the presence of gross pathological changes of the middle ear cleft.


Assuntos
Otite Média Supurativa/patologia , Osso Temporal/patologia , Membrana Timpânica/patologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Colesteatoma/epidemiologia , Colesteatoma/etiologia , Colesteatoma/patologia , Doença Crônica , Feminino , Tecido de Granulação/patologia , Granuloma/epidemiologia , Granuloma/etiologia , Granuloma/patologia , Humanos , Incidência , Lactente , Labirintite/epidemiologia , Labirintite/etiologia , Labirintite/patologia , Masculino , Pessoa de Meia-Idade , Otite Média Supurativa/complicações , Otite Média Supurativa/epidemiologia , Estudos Retrospectivos , Ruptura Espontânea
15.
Am J Otol ; 10(5): 358-63, 1989 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2817105

RESUMO

Thirty cases of congenital cholesteatomas of the cerebellopontine angle (CPA) treated over a period of 20 years are reviewed with regard to their clinical features, the pathophysiology of their symptoms, and their management. The predominant symptoms were related to cranial nerves VII and VIII and headaches. Signs and symptoms were divided into those caused by local involvement of the cholesteatoma, increased intracranial pressure, or both. Diagnostic procedures from invasive procedures such as ventriculography to more sophisticated noninvasive procedures including computed tomography and magnetic resonance imaging are discussed. The surgical management of 27 congenital cholesteatomas was accomplished via a posterior cranial fossa approach. Total excision of the cholesteatoma was the aim but was carried out in only five (18%) patients because of concern regarding the preservation of nearby neurovascular structures. Partial excision was possible in 22 (82%) patients. To minimize re-formation, the residual cholesteatoma was carefully cauterized with the aid of the operating microscope and bipolar diathermy without damaging surrounding neurovascular structures. Follow-up has ranged from 2 to 15 years, with four (13%) cases of re-formation.


Assuntos
Doenças Cerebelares/congênito , Ângulo Cerebelopontino , Colesteatoma/congênito , Adolescente , Adulto , Doenças Cerebelares/fisiopatologia , Doenças Cerebelares/cirurgia , Ângulo Cerebelopontino/diagnóstico por imagem , Ângulo Cerebelopontino/cirurgia , Criança , Colesteatoma/fisiopatologia , Colesteatoma/cirurgia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Radiografia , Estudos Retrospectivos
16.
Otolaryngol Clin North Am ; 22(1): 41-9, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2704563

RESUMO

A combination of otologic techniques has been presented in the step-wise surgical rationale that we call the flexible approach. The sequence of steps involved in the flexible approach allows the surgeon to adjust his or her surgery to the individual patient's needs. Very often, in patients with chronic otitis media, a middle ear reconstructive procedure (ossiculoplasty including lateralization of the malleus, removal of pathological tissue, insertion of an implant of silicone rubber sheets, and use of ventilation tubes with or without tympanic grafts) will obviate mastoidectomy. When a mastoidectomy is indicated, the IBM is a suitable procedure that encompasses the advantages of both closed and open mastoidectomy techniques.


Assuntos
Processo Mastoide/cirurgia , Otite Média/cirurgia , Timpanoplastia/métodos , Humanos , Métodos
17.
Surg Neurol ; 15(4): 294-7, 1981 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7245016

RESUMO

A case is described of suprasellar tumor with diabetes insipidus, diminishing visual acuity, inferior bitemporal quadrantanopia, and hypopituitarism in a 19-year-old man. Computerized tomographic scan of the brain after contrast injection demonstrated periventricular enhancement. Diagnosis of germinoma was made on the basis of clinical and radiographic information and a biopsy that revealed malignant cells. The tumor responded well to radiation therapy. Diagnostic difficulties were created by systemic manifestations unrelated to endocrinopathy. Pertinent literature is reviewed.


Assuntos
Neoplasias Encefálicas/diagnóstico , Glândula Pineal , Pinealoma/diagnóstico , Adulto , Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/radioterapia , Diabetes Insípido/etiologia , Diagnóstico Diferencial , Humanos , Hipopituitarismo/etiologia , Masculino , Pinealoma/complicações , Pinealoma/radioterapia , Transtornos da Visão/etiologia
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