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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 261: 120046, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34139661

RESUMO

The extremophile lichen Circinaria gyrosa (C. gyrosa) is one of the selected species within the BIOMEX (Biology and Mars Experiment) experiment. Here we present the Raman study of a biohint found in this lichen, called whewellite (calcium oxalate monohydrate), and other organic compounds and mineral products of the biological activity of the astrobiologically relevant model system C. gyrosa. Samples were exposed to space- and simulated Mars-like conditions during the EXPOSE-R2 mission parallel ground reference experiment MGR performed at the space- and planetary chambers of DLR-Cologne to study Mars' habitability and resistance to real space conditions. In this work, we complete the information of natural C. gyrosa about the process of diagenesis by the identification of carbonate crystals in the inner medulla together with the biomineral whewellite. The analysis by Raman spectroscopy of simulated Space and Mars exposed samples confirm alterations and damages of the photobiont part of the lichen and changes related to the molecular structure of whewellite. The conclusions of this work will be important to understand what are the effects to consider when biological systems are exposed to space or Mars-like conditions and to expand our knowledge of how life survives in most extreme conditions that is a prerequisite in future planetary exploration projects.


Assuntos
Líquens , Voo Espacial , Ascomicetos , Exobiologia , Meio Ambiente Extraterreno , Análise Espectral Raman
2.
Med Oral Patol Oral Cir Bucal ; 24(4): e433-e437, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31232385

RESUMO

BACKGROUND: The aim was to describe the recurrence rates of Oral Squamous Cell Papilloma (OSCP) following surgical treatment with surgical scalpel and two different lasers (CO2 or Er,Cr;YSGG) and to determine the clinical and histopathologic features of these lesions. MATERIAL AND METHODS: A retrospective cohort study covering a period of 12 years (1997-2009) that included patients diagnosed of OSCP treated with surgical excision was performed. Data was processed using SPSS 22.0 (SPPS Inc. Chicago, USA) and a descriptive and bivariate analysis were conducted. RESULTS: A total of 37 histopathologically confirmed OSCP in 36 patients, 19 women (52.7%) and 17 men (47.2%) with an average age of 33.4 years (14-86 years) were included. Twenty-two cases were treated by excision with surgical scalpel excision, 11 with CO2 laser and 3 with Er,Cr:YSGG laser. The mean age was 35.4 years (14-86 years) and the distribution by gender was 19 women (52.7%) and 17 men (47.2%). The most common locations were the palate in 14 cases (37.8%), followed by the tongue in 11 cases (29.7%) and gingiva with 5 cases (13.5%). The average size of the lesions was 4.25 mm in diameter, with a mean evolution time of 5.9 months. The recurrence rate was slightly higher with the CO2 laser (14.3 %) in comparison with the conventional scalpel (10%). No recurrences for Er,Cr:YSGG were found. CONCLUSIONS: No differences for recurrence rates for OSCP between groups were found. The recurrence rate is low, happening usually before 15 months of follow-up. OSCPs are lesions usually appearing in patients between 30 and 50 years of both genders and located predominantly on the palate, tongue and gingiva.


Assuntos
Terapia a Laser , Lasers de Estado Sólido , Adulto , Células Epiteliais , Feminino , Humanos , Masculino , Recidiva Local de Neoplasia , Estudos Retrospectivos
3.
Rev Gastroenterol Mex ; 82(3): 210-216, 2017.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-28325647

RESUMO

BACKGROUND: In relation to the number of new cases diagnosed, gastric cancer is the fourth most common cancer worldwide, and the second cause of cancer death. The development of multidetector tomography has improved the preoperative staging of gastric cancer. AIM: To correlate preoperative tomographic studies with the definitive pathologic results according to the TNM staging system. METHODS: A retrospective, cross-sectional study within the time frame of January 2009 to December 2013 was conducted that included the case records of 67 patients. They all had upper endoscopy and preoperative multidetector tomography examinations, underwent surgical resection, and had the corresponding histopathology study. Statistical analysis was carried out with the SPSS version 15.0 software and the sensitivity and specificity calculations were made using the Excel 2011 program for Mac. RESULTS: The majority of the patients included in the case series had clinical stage iii and iv disease. When compared with the histopathologic result, the overall accuracy of multidetector CT was 83% (T0 96%, T1 94%, T2 93%, T3 67%, and T4 67%) for tumor size (T) and was 70% (N0 72%, N1 73%, N2 70%, and N3 66%) for lymph node involvement (N). Overall sensitivity was 48% (T0 100%, T1 0%, T2 33%, T3 44%, and T4 65%) for T and was 41% (N0 58%, N1 56%, N2 15%, and N3 35%) for N. A strong association between the multidetector CT results and the pathology results was demonstrated through the Spearman's correlation, especially in T4 and N3. CONCLUSIONS: Multidetector computed tomography showed greater congruency in detecting stages T4, N0, and N3 in gastric cancer, when compared with the definitive histopathologic results.


Assuntos
Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/patologia , Tomografia Computadorizada Multidetectores , Cuidados Pré-Operatórios , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/patologia , Adenocarcinoma/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Hospitais Militares , Humanos , Masculino , México , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Retrospectivos , Sensibilidade e Especificidade , Neoplasias Gástricas/cirurgia
4.
Phys Chem Chem Phys ; 16(42): 22958-61, 2014 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-25255295

RESUMO

DFT calculations predict two different electronic structures of metal-molecule hybrids which are selected depending on the surface charge. While the metal-to-molecule CT states are very sensitive to the charge, the energies of the reverse molecule-to-metal CT processes are surprisingly not modified at all by the charge of the metal.

5.
J Neurosci ; 33(16): 6857-63, 2013 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-23595744

RESUMO

Blood-brain barrier (BBB) dysfunction is a major hallmark of many neurological diseases, including multiple sclerosis (MS). Using a genomics approach, we defined a microRNA signature that is diminished at the BBB of MS patients. In particular, miR-125a-5p is a key regulator of brain endothelial tightness and immune cell efflux. Our findings suggest that repair of a disturbed BBB through microRNAs may represent a novel avenue for effective treatment of MS.


Assuntos
Barreira Hematoencefálica/fisiopatologia , Encéfalo/patologia , Células Endoteliais/fisiologia , Inflamação/patologia , MicroRNAs/metabolismo , Esclerose Múltipla/patologia , Barreira Hematoencefálica/efeitos dos fármacos , Linhagem Celular Transformada , Citocinas/metabolismo , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Vetores Genéticos/fisiologia , Humanos , MicroRNAs/genética , RNA Interferente Pequeno/farmacologia , Migração Transendotelial e Transepitelial/efeitos dos fármacos , Transfecção
6.
J Immunol ; 189(6): 3130-9, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-22896632

RESUMO

During neuroinflammation, cytokines such as TNF-α and IFN-γ secreted by activated leukocytes and/or CNS resident cells have been shown to alter the phenotype and function of brain endothelial cells (BECs) leading to blood-brain barrier breakdown. In this study, we show that the human BEC line hCMEC/D3 expresses the receptors for TNF-α, TNF receptor 1 and TNF receptor 2, and for IFN-γ. BEC activation with TNF-α alone or in combination with IFN-γ induced endothelial leakage of paracellular tracers. At high cytokine concentrations (10 and 100 ng/ml), this effect was associated with caspase-3/7 activation and apoptotic cell death as evidenced by annexin V staining and DNA fragmentation (TUNEL) assays. In addition, inhibition of JNK and protein kinase C activation at these doses partially prevented activation of caspase-3/7, although only JNK inhibition was partially able to prevent the increase in BEC paracellular permeability induced by cytokines. By contrast, lower cytokine concentrations (1 ng/ml) also led to effector caspase activation, increased paracellular flux, and redistribution of zonula occludens-1 and VE-cadherin but failed to induce apoptosis. Under these conditions, specific caspase-3 and caspase-9, but not caspase-8, inhibitors partially blocked cytokine-induced disruption of tight and adherens junctions and BEC paracellular permeability. Our results suggest that the concentration of cytokines in the CNS endothelial microenvironment determines the extent of caspase-mediated barrier permeability changes, which may be generalized as a result of apoptosis or more subtle as a result of alterations in the organization of junctional complex molecules.


Assuntos
Barreira Hematoencefálica/enzimologia , Barreira Hematoencefálica/imunologia , Encéfalo/enzimologia , Encéfalo/imunologia , Citocinas/fisiologia , Endotélio Vascular/enzimologia , Endotélio Vascular/imunologia , Barreira Hematoencefálica/patologia , Encéfalo/patologia , Linhagem Celular , Endotélio Vascular/patologia , Humanos , Mediadores da Inflamação/metabolismo , Mediadores da Inflamação/fisiologia , Interferon gama/metabolismo , Microcirculação/imunologia , Receptores de Interferon/biossíntese , Receptores Tipo I de Fatores de Necrose Tumoral/biossíntese , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Receptores Tipo II do Fator de Necrose Tumoral/biossíntese , Receptores Tipo II do Fator de Necrose Tumoral/metabolismo , Frações Subcelulares/enzimologia , Frações Subcelulares/imunologia , Frações Subcelulares/patologia
7.
Av. periodoncia implantol. oral ; 23(3): 171-186, dic. 2011.
Artigo em Espanhol | IBECS | ID: ibc-104920

RESUMO

Debido al amplio número de publicaciones que existen sobre Implantología Bucofacial, resulta difícil para el odontólogo seleccionar y leer de forma crítica una cantidad suficiente de artículos que puedan aportarle una información útil para su praxis diaria. En este artículo pretendemos sintetizar la información más relevante que se encuentra en las revistas indexadas de la especialidad publicadas el año 2009 (AU)


The lack of the available time of the professionals involved in the Odontologic field and the difficulty to achieve a good level of information about Oral Implantology, arise the interest of the authors to expose a synthetic review of the publications. This article tries to summarize the most relevant information found in the journals of the specialty published in 2009 (AU)


Assuntos
Humanos , Implantes Dentários , /métodos , Implantação Dentária/métodos , Engenharia Celular , Implantação Dentária Endóssea/efeitos adversos , Osteogênese por Distração
8.
J Pharm Sci ; 100(11): 4815-22, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21713774

RESUMO

Lipid nanoparticles functionalized with the sunscreen 2,4-dihydroxybenzophenone (FLNPs) have been prepared by the ultrasound method and embedded in highly hydrophilic cellophane supports (regenerated cellulose, RC), creating biocompatible hybrid films (RC-FLNPs samples). The morphology of the FLNPs was studied with transmission microscopy, whereas the surface and interior chemical composition was analyzed by micro-Raman spectroscopy. RC-FLNPs hybrid films were prepared from the immersion of two cellophane supports with different thicknesses and water uptake properties (RC-3 and RC-6) in an aqueous dispersion of FLNPs. The structure of this hybrid material was visualized with bright-field microscopy, which clearly showed the inclusion of the FLNPs in the cellophane matrix. The stability of the RC-FLNPs films with respect to both aqueous environments and time was demonstrated by NaCl diffusion measurements. The reduction in the diffusion coefficient through the nanoparticle-modified films compared with the original supports confirms the presence of nanoparticles for concentration gradients of up to 0.4 M (osmotic pressure around 10 bar), indicating the stability of the hybrid hydrophilic material, even in aqueous environments and under matter flow conditions for a period of 21 days.


Assuntos
Celofane , Estabilidade de Medicamentos , Lipídeos/química , Nanopartículas , Microscopia Eletrônica de Transmissão , Análise Espectral Raman
9.
Av. periodoncia implantol. oral ; 23(1): 49-73, abr. 2011.
Artigo em Espanhol | IBECS | ID: ibc-96732

RESUMO

Debido al amplio número de publicaciones que existen sobre Implantología Bucofacial, resulta difícil para el odontólogo seleccionar y leer de forma crítica una cantidad suficiente de artículos que puedan aportarle una información útil para su praxis diaria. En este artículo se pretende sintetizarla información más relevante que se encuentra en las revistas indexadas de la especialidad publicadas durante el año 2009 (AU)


The lack of the available time of the professionals involved in the odontologic field and the difficulty to achieve a good level of information about Oral Implantology, arise the interest of the authors to expose a synthetic review of the publications. This article tries to summarize the most relevant information found in the journals of the specialty published in 2009 (AU)


Assuntos
Humanos , Implantação Dentária/tendências , Carga Imediata em Implante Dentário/tendências , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Regeneração Tecidual Guiada/métodos , /métodos , Fatores de Risco , Periodontite/complicações , Fumar/efeitos adversos , Diabetes Mellitus Tipo 2/complicações , Osteoporose/complicações
10.
Brain Res ; 1292: 14-24, 2009 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-19631619

RESUMO

P-glycoprotein (P-gp) expression at the blood-brain barrier prevents unwanted blood-borne toxins and signalling molecules from entering the brain. Primary and immortalised human brain endothelial cells (BECs) represent two suitable options for studying P-gp function in vitro. The limited supply of primary human BECs and their instability over passage number make this choice unattractive for medium/high throughput studies. The aim of this study was to further characterise the expression of P-gp by an immortalised human BEC line, hCMEC/D3, in order to evaluate their use as an in vitro human blood-brain barrier model. P-gp expression was stable over a high passage number (up to passage 38) and was polarised on the apical plasma membrane, consistent with human BECs in vivo. In addition, hCMEC/D3 cell P-gp expression was comparable, albeit slightly lower to that observed in primary isolated human BECs although P-gp function was similar in both cell lines. The P-gp inhibitors tariquidar and vinblastine prevented the efflux of rhodamine 123 (rh123) from hCMEC/D3 cells, indicative of functional P-gp expression. hCMEC/D3 cells also displayed polarised P-gp transport, since both tariquidar and vinblasine selectively increased the apical-to-basolateral permeability of hCMEC/D3 cells to rh123. The results presented here demonstrate that hCMEC/D3 cells are a suitable model to investigate substrate specificity of P-gp in BECs of human origin.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Encéfalo/fisiologia , Permeabilidade da Membrana Celular/fisiologia , Células Endoteliais/fisiologia , Corantes Fluorescentes/farmacocinética , Rodamina 123/farmacocinética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Transporte Biológico/efeitos dos fármacos , Barreira Hematoencefálica/fisiologia , Encéfalo/efeitos dos fármacos , Permeabilidade Capilar , Linhagem Celular , Membrana Celular/efeitos dos fármacos , Membrana Celular/fisiologia , Células Cultivadas , Fármacos do Sistema Nervoso Central/farmacologia , Células Endoteliais/efeitos dos fármacos , Humanos , Modelos Biológicos , Quinolinas/farmacologia , Vimblastina/farmacologia
11.
J Colloid Interface Sci ; 332(1): 130-5, 2009 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-19167008

RESUMO

Surface-enhanced Raman scattering (SERS) of hydroxybenzoic acids has been studied on silver sols in H(2)O and D(2)O solutions. The adsorption behavior of 4-hydroxybenzoic acid (4HBA) is different from that of salicylic (2HBA) and 3-hydroxybenzoic (3HBA) acids. It was concluded that 4HBA is adsorbed on silver nanoparticles (Ag(n)) as either oxidobenzoate (A(2-)) or hydroxybenzoate (A(-)), depending on the pH of the solution, given rise to a flat orientation. Both 2HBA and 3HBA acids are always adsorbed as hydroxybenzoates anions (A(-)) at pH >or=5 and link to the metal through the carboxylate group (Ag(n)--A(-)), standing more or less perpendicular to the metal surface. In the case of these monoanions, the selective enhancement of the bands is due mainly to a resonant electron or charge transfer process (ET or CT) from the metallic nanoparticles to the adsorbates, yielding the transient formation of the respective radical dianions (Ag(+)(n)--A(2-)). It is found that the enhanced bands, and especially the mode 8a;nu(ring), are related to the difference between the equilibrium structures of the adsorbate in its ground (A(-)) and CT-excited (A(2-)) states. In the SERS spectrum of 4HBA dianion, the contribution of CT mechanism is not observed.

12.
Biopolymers ; 82(4): 379-83, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16538609

RESUMO

The surface-enhanced Raman scattering (SERS) of salicylic acid (S) adsorbed on a silver sol in H(2)O and D(2)O has been investigated. At pH 5 or greater, the adsorbed species is the salicylate anion (2-hydroxybenzoate anion) (S(-)), which links to the metal nanoparticle (Ag(n)) through the carboxylate group (S(-)-Ag(n)). We demonstrate that the selective enhancement of the bands is due mainly to a resonant electron or charge transfer process (ET or CT) from the metallic nanoparticle to the adsorbate, yielding the transient formation of the respective radical dianion (S.(2-)-Ag(n) (+)). It is found that the enhanced bands, and especially mode 8a;nu(ring), are related to the differences between the equilibrium structures of the adsorbate in its ground (S(-)) and CT-excited states (S.(2-)).


Assuntos
Nanoestruturas/química , Salicilatos/química , Prata/química , Análise Espectral Raman/métodos , Adsorção , Transporte de Elétrons , Modelos Moleculares , Nanotecnologia/métodos
13.
J Pediatr Surg ; 40(9): e25-7, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16150329

RESUMO

Buschke-Löwenstein tumor or giant condyloma is a warty verrucous lesion, characterized by slow growth, locally infiltrating and disfiguring lesions. Despite its benign histological appearance and low risk of metastasis, Buschke-Löwenstein tumor is an intermediate lesion between condyloma acuminatum and verrucous carcinoma. It has been linked to human papilloma virus, mainly subtypes 6 and 11. Other factors implicated in this disease include poor hygiene, chronic irritation, promiscuity, and cellular immunocompromised states. It rarely occurs in children. The first line of treatment is radical surgical excision with or without adjuvant chemotherapy. We report the case of a 12-year-old girl with a giant perianal condyloma that was treated with surgical excision and a 6-week course of 5-fluorouracil beginning 6 weeks after surgery, with excellent functional and cosmetic results.


Assuntos
Neoplasias do Ânus/tratamento farmacológico , Carcinoma Verrucoso/tratamento farmacológico , Condiloma Acuminado/tratamento farmacológico , Antimetabólitos Antineoplásicos/uso terapêutico , Neoplasias do Ânus/cirurgia , Carcinoma Verrucoso/cirurgia , Criança , Condiloma Acuminado/cirurgia , Feminino , Fluoruracila/uso terapêutico , Humanos , Resultado do Tratamento
14.
Biopolymers ; 74(1-2): 141-5, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15137112

RESUMO

The vibration nu(SH) has never been observed in the surface-enhanced Raman scattering of mercaptoacetic acid recorded in a wide range of pH. This behavior enables us to deduce that the -SH group is deprotonated and links to the metal forming an Ag-S bond as 1-alkanethiols do. On the contrary, the carboxylic or carboxylate groups do not link to the metal and the carboxylic group is preserved even at pH values under which it should be deprotonated. This fact enables the stabilization of the adsorbed monolayer by removing the electrostatic repulsions between -COO(-) groups and by the formation instead of hydrogen bonds between carboxylic groups. Only under rather basic conditions (pH > 8) does the carboxylic groups dissociate, but the nu(s)(OCO) band is neither enhanced nor shifted toward low frequencies.


Assuntos
Coloides/química , Análise Espectral Raman/métodos , Tioglicolatos/química , Adsorção , Ácidos Carboxílicos/metabolismo , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio , Modelos Químicos , Eletricidade Estática
15.
J Colloid Interface Sci ; 263(2): 357-63, 2003 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-12909024

RESUMO

Raman and SERS spectra of phenylacetic acid and alpha-phenylglycine on silver sols have been recorded at several concentrations and pH values. The alpha-phenylglycine has been also studied in D(2)O. The respective vibrational assignments have been proposed and the analysis of the SERS spectra has made it possible to conclude that phenylacetic acid links to the metal through its carboxylate group only, while alpha-phenylglycine links also through its amino group. In both cases the aromatic ring seems to be almost perpendicular to the metal surface. On the other hand, the contribution of the charge transfer (CT) mechanism to the enhancement of the SERS spectra has been calculated as well and it is found to be very important in both molecules. The band most enhanced by this mechanism is that of vibration 8a, mainly in alpha-phenylglycine.


Assuntos
Hidrocarbonetos/química , Fenilacetatos/química , Polímeros/química , Tensoativos/química , Adsorção , Fenômenos Biofísicos , Biofísica , Carbono/química , Microscopia de Força Atômica , Modelos Químicos , Aço/química , Temperatura
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