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1.
Int J Cosmet Sci ; 45 Suppl 1: 84-92, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37625851

RESUMO

OBJECTIVE: Significant research and regulatory attention have been focussed on the potential for some ultraviolet filters (UVFs) to rinse off from beachgoers' skin into seawater leading to exposure to sea life, especially coral reefs. The amount of UVFs potentially rinsed from skin during recreational beach activities has not been well studied, leading to uncertainty about the potential magnitude of aquatic UVF exposure due to changes in sunscreen use patterns. This study quantifies rinse-off of UVFs in sunscreen from skin into synthetic seawater and identifies differences in rinse-off quantity due to formulation type with a goal of informing future modelling efforts aimed at estimating UVF exposure to sea life associated with recreational activities at the beach. METHODS: UVF rinse-off from skin during recreation in seawater was simulated by applying eight different sunscreen products to porcine skin samples followed by three periods of shaking in synthetic seawater totalling 40 min. The rinsed mass of six UVFs - zinc oxide, titanium dioxide, avobenzone, homosalate, octisalate, and octocrylene - was determined analytically in synthetic seawater and in extractant rinsate from glassware for organic UVFs and compared among formulas. RESULTS: Among the 22 UVF-formulation combinations tested, 19 resulted in less than 10% of the applied UVF rinsed from skin. All formulation-UVF combinations where the formula types were water-in-oil (reverse phase) emulsions or anhydrous resulted in 5% or less of the applied UVF rinsed to synthetic seawater. Sunscreens formulated as oil-in-water emulsions yielded higher rinse-off percentages for all UVFs tested, with a maximum of 20% rinse-off of avobenzone in one lotion. CONCLUSION: The potential for sunscreen UVF rinse-off is significantly influenced by formulation and is generally well below the prior assumed rinse-off levels used to estimate risk. Formulation consideration is therefore essential for accurate exposure models used in environmental risk assessment. Anhydrous and reverse phase (water-in-oil) sunscreen formulations tested resulted in lower UVF transfer from skin to synthetic seawater in simulated ocean bathing tests and as a result, are expected to yield lower UVF exposures to sea life. This approach can be used in predictive environmental exposure models to support ecologically safe sunscreen formulation design.


OBJECTIF: Des recherches importantes ont été effectuées et l'attention réglementaire a été portée sur le potentiel de certains filtres ultraviolets (UVF) à être rincés de la peau de baigneurs par l'eau de mer à la plage, entraînant une exposition à la vie marine, en particulier aux récifs coralliens. La quantité d'UVF potentiellement rincée de la peau pendant les activités récréatives sur la plage n'a pas été étudiée de manière approfondie, ce qui entraîne une incertitude quant à l'ampleur potentielle de l'exposition aux UVF dans l'eau en raison des changements dans les habitudes d'utilisation de la crème solaire. Cette étude quantifie le rinçage des UVF contenus dans la crème solaire appliquée sur la peau par de l'eau de mer reconstituée et identifie les différences dans la quantité UVF rinçés selon le type de formulation afin d'éclairer les futurs efforts de modélisation visant à estimer l'exposition des UVF à la vie marine associée aux activités récréatives à la plage. MÉTHODES: Le rinçage des UVF pendant les loisirs en eau de mer a été simulé en appliquant huit produits de protection solaire différents sur des échantillons de peau porcine, suivis de trois périodes d'agitation dans de l'eau de mer reconstituée d'une durée totale de 40 min. La masse rincée de six UVF - oxyde de zinc, dioxyde de titane, avobenzone, homosalate, octisalate et octocrylène - a été déterminée analytiquement dans l'eau de mer reconstituée et en solution pour les UVF organiques, et une comparaison entre les formules a été effectuée. RÉSULTATS: Parmi les 22 combinaisons de formulations UVF testées, 19 ont entraîné le rinçage de moins de 10 % des UVF appliqués sur la peau. Toutes les combinaisons de formulations UVF où les types de formule étaient des émulsions eau dans huile (phase inverse) ou anhydres ont entraîné 5 % ou moins de rinçage des UVF appliquées dans l'eau de mer reconstituée. Les écrans solaires formulés sous forme d'émulsions huile dans l'eau ont produit des pourcentages de rinçage plus élevés pour tous les UVF testés, avec un maximum de 20 % de rinçage pour l'avobenzone pour une lotion. CONCLUSION: Le potentiel de rinçage des UVF de l'écran solaire est significativement influencé par la formulation et est généralement bien inférieur aux niveaux de rinçage précédemment supposés, utilisés pour estimer le risque. La prise en compte de la formulation est donc essentielle pour obtenir des modèles d'exposition exacts utilisés dans l'évaluation des risques environnementaux. Les formulations de crème solaire anhydre et en phase inverse (eau dans l'huile) testées ont entraîné un transfert plus faible des UVF dans l'eau de mer reconstituée dans des tests de simulation de bain de mer et, par conséquent, devraient entrainer une exposition plus faible des UVF à la vie marine. Cette approche peut être utilisée dans des modèles prédictifs d'exposition environnementale pour soutenir une conception de crème solaire écologiquement sûre.


Assuntos
Água do Mar , Protetores Solares , Animais , Suínos , Água , Minerais , Oceanos e Mares , Raios Ultravioleta
2.
Bioorg Med Chem Lett ; 30(23): 127625, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33096160
3.
Bioorg Med Chem Lett ; 29(3): 491-495, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30553737
4.
J Cosmet Sci ; 68(1): 42-47, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29465381

RESUMO

Polyglycerol (PG) is a well-known cosmetic ingredient and important precursor for the synthesis of a variety of cosmetic ingredients, such as surfactants, emulsifiers, and conditioning agents for hair and skin. When derived from renewable resources, PG can provide a more sustainable platform for the development of new ingredients with improved performance in cosmetic applications. This paper will discuss recent advances in the utilization of bio-based PG ingredients as alternatives to traditional ethoxylate chemistries for mild nonionic surfactants, substantive humectants, and micellar thickeners.


Assuntos
Cosméticos/síntese química , Cosméticos/farmacologia , Glicerol/química , Glicerol/farmacologia , Polímeros/química , Polímeros/farmacologia , Pele/efeitos dos fármacos , Animais , Desenho de Fármacos , Cabelo/efeitos dos fármacos , Humanos , Polissorbatos/química , Polissorbatos/farmacologia , Envelhecimento da Pele/efeitos dos fármacos
5.
Bioorg Med Chem Lett ; 26(3): 1090-1096, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26750252

RESUMO

Anaplastic lymphoma kinase (ALK) is a receptor tyrosine kinase belonging to the insulin receptor superfamily. Expression of ALK in normal human tissues is only found in a subset of neural cells, however it is involved in the genesis of several cancers through genetic aberrations involving translocation of the kinase domain with multiple fusion partners (e.g., NPM-ALK in anaplastic large cell lymphoma ALCL or EML4-ALK in non-small cell lung cancer) or activating mutations in the full-length receptor resulting in ligand-independent constitutive activation (e.g., neuroblastoma). Here we are reporting the discovery of novel and selective anaplastic lymphoma kinase inhibitors from specific modifications of the 2,4-diaminopyridine core present in TAE684 and LDK378. Synthesis, structure activity relationships (SAR), absorption, distribution, metabolism, and excretion (ADME) profile, and in vivo efficacy in a mouse xenograft model of anaplastic large cell lymphoma are described.


Assuntos
Antineoplásicos/síntese química , Desenho de Fármacos , Inibidores de Proteínas Quinases/síntese química , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , 4-Aminopiridina/análogos & derivados , 4-Aminopiridina/química , Quinase do Linfoma Anaplásico , Animais , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapêutico , Sítios de Ligação , Linhagem Celular Tumoral , Cristalografia por Raios X , Meia-Vida , Humanos , Linfoma Anaplásico de Células Grandes/tratamento farmacológico , Camundongos , Camundongos SCID , Microssomos Hepáticos/metabolismo , Simulação de Dinâmica Molecular , Inibidores de Proteínas Quinases/farmacocinética , Inibidores de Proteínas Quinases/uso terapêutico , Estrutura Terciária de Proteína , Ratos , Receptores Proteína Tirosina Quinases/metabolismo , Relação Estrutura-Atividade , Transplante Heterólogo
6.
Proc Natl Acad Sci U S A ; 109(24): 9276-80, 2012 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-22645366

RESUMO

Spontaneous degradation of bottlebrush macromolecules on aqueous substrates was monitored by atomic force microscopy. Scission of C ─ C covalent bonds in the brush backbone occurred due to steric repulsion between the adsorbed side chains, which generated bond tension on the order of several nano-Newtons. Unlike conventional chemical reactions, the rate of bond scission was shown to decrease with temperature. This apparent anti-Arrhenius behavior was caused by a decrease in the surface energy of the underlying substrate upon heating, which results in a corresponding decrease of bond tension in the adsorbed macromolecules. Even though the tension dropped minimally from 2.16 to 1.89 nN, this was sufficient to overpower the increase in the thermal energy (k(B)T) in the Arrhenius equation. The rate constant of the bond-scission reaction was measured as a function of temperature and surface energy. Fitting the experimental data by a perturbed Morse potential V = V(0)(1 - e(-ßx))(2) - fx, we determined the depth and width of the potential to be V(0) = 141 ± 19 kJ/mol and ß(-1) = 0.18 ± 0.03 Å, respectively. Whereas the V(0) value is in reasonable agreement with the activation energy E(a) = 80-220 kJ/mol of mechanical and thermal degradation of organic polymers, it is significantly lower than the dissociation energy of a C ─ C bond D(e) = 350 kJ/mol. Moreover, the force constant K(x) = 2ß(2)V(0) = 1.45 ± 0.36 kN/m of a strained bottlebrush along its backbone is markedly larger than the force constant of a C ─ C bond K(l) = 0.44 kN/m, which is attributed to additional stiffness due to deformation of the side chains.

7.
Hum Brain Mapp ; 35(5): 2424-34, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-23982962

RESUMO

Multisite longitudinal neuroimaging designs are used to identify differential brain structural change associated with onset or progression of disease. The reliability of neuroanatomical measurements over time and across sites is a crucial aspect of power in such studies. Prior work has found that while within-site reliabilities of neuroanatomical measurements are excellent, between-site reliability is generally more modest. Factors that may increase between-site reliability include standardization of scanner platform and sequence parameters and correction for between-scanner variations in gradient nonlinearities. Factors that may improve both between- and within-site reliability include use of registration algorithms that account for individual differences in cortical patterning and shape. In this study 8 healthy volunteers were scanned twice on successive days at 8 sites participating in the North American Prodrome Longitudinal Study (NAPLS). All sites employed 3 Tesla scanners and standardized acquisition parameters. Site accounted for 2 to 30% of the total variance in neuroanatomical measurements. However, site-related variations were trivial (<1%) among sites using the same scanner model and 12-channel coil or when correcting for between-scanner differences in gradient nonlinearity and scaling. Adjusting for individual differences in sulcal-gyral geometries yielded measurements with greater reliabilities than those obtained using an automated approach. Neuroimaging can be performed across multiple sites at the same level of reliability as at a single site, achieving within- and between-site reliabilities of 0.95 or greater for gray matter density in the majority of voxels in the prefrontal and temporal cortical surfaces as well as for the volumes of most subcortical structures.


Assuntos
Mapeamento Encefálico , Encéfalo/patologia , Transtornos Psicóticos/patologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Reprodutibilidade dos Testes , Estatística como Assunto
8.
Toxicol In Vitro ; 98: 105835, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38679218

RESUMO

Octocrylene is a common sun filter ingredient used to protect the skin from damaging UV rays. Benzophenone is an impurity found in formulations containing octocrylene. [14C]-Benzophenone was spiked (0.1 g/L) into 2 commercial sunscreen formulations; Neutrogena® Beach Defense Sunscreen Spray Broad Spectrum SPF 70 Aerosol, Neutrogena® Ultra Sheer Body Mist Sunscreen Broad Spectrum SPF 30 Aerosol, and an acetone vehicle. The formulations were applied (ca 2 µL/cm2) to dermatomed human skin mounted in static diffusion cells in vitro. Receptor fluid was collected up to 24 h post dose. All samples were analyzed by liquid scintillation counting. The dermal delivery of [14C]-Benzophenone was 10.02, 9.04 and 5.19% for the 3 formulations. However, the [14C]-Benzophenone mass balances were low; 81.5, 85.3 and 8.02%, respectively. A volatility test was performed replacing skin with aluminum foil for the sunscreen formulations only. The [14C]-Benzophenone mass balance at dosing was 99% but fell to 56.9 and 60.6% at 24 h post dose, confirming the losses were due to [14C]-Benzophenone volatility. A conservative dermal absorption value of 12.42% was proposed to cover [14C]-Benzophenone containing formulations.


Assuntos
Benzofenonas , Radioisótopos de Carbono , Absorção Cutânea , Pele , Protetores Solares , Benzofenonas/farmacocinética , Benzofenonas/administração & dosagem , Humanos , Protetores Solares/farmacocinética , Protetores Solares/química , Protetores Solares/administração & dosagem , Pele/metabolismo , Técnicas In Vitro , Acrilatos/química , Acrilatos/farmacocinética
9.
Eur Arch Psychiatry Clin Neurosci ; 263(6): 469-73, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23161338

RESUMO

Via influencing brain plasticity, aerobic exercise could contribute to the treatment of schizophrenia patients. As previously shown, physical exercise increases hippocampus volume and improves short-term memory. We now investigated gray matter density and brain surface expansion in this sample using MRI-based cortical pattern matching methods. Comparing schizophrenia patients to healthy controls before and after 3 months of aerobic exercise training (cycling) plus patients playing table football yielded gray matter density increases in the right frontal and occipital cortex merely in healthy controls. However, respective exercise effects might be attenuated in chronic schizophrenia, which should be verified in a larger sample.


Assuntos
Córtex Cerebral/patologia , Exercício Físico/fisiologia , Esquizofrenia/patologia , Esquizofrenia/reabilitação , Adulto , Mapeamento Encefálico , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
10.
Nature ; 440(7081): 191-4, 2006 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-16525468

RESUMO

Covalent carbon-carbon bonds are hard to break. Their strength is evident in the hardness of diamonds and tensile strength of polymeric fibres; on the single-molecule level, it manifests itself in the need for forces of several nanonewtons to extend and mechanically rupture one bond. Such forces have been generated using extensional flow, ultrasonic irradiation, receding meniscus and by directly stretching a single molecule with nanoprobes. Here we show that simple adsorption of brush-like macromolecules with long side chains on a substrate can induce not only conformational deformations, but also spontaneous rupture of covalent bonds in the macromolecular backbone. We attribute this behaviour to the fact that the attractive interaction between the side chains and the substrate is maximized by the spreading of the side chains, which in turn induces tension along the polymer backbone. Provided the side-chain densities and substrate interaction are sufficiently high, the tension generated will be strong enough to rupture covalent carbon-carbon bonds. We expect similar adsorption-induced backbone scission to occur for all macromolecules with highly branched architectures, such as brushes and dendrimers. This behaviour needs to be considered when designing surface-targeted macromolecules of this type-either to avoid undesired degradation, or to ensure rupture at predetermined macromolecular sites.

11.
J Nutr ; 141(6): 1023-8, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21490291

RESUMO

Lactobacillus johnsonii (Ljo) N6.2 has been shown to mitigate the development of type 1 diabetes when administered to diabetes-prone rats. The specific mechanisms underlying this observed response remain under investigation. The objective of this study was to assess the effect of Ljo N6.2 on mucosal inflammatory response using differentiated Caco-2 monolayers. The mRNA expression levels of CCL20, CXCL8, and CXCL10 chemokines were determined by qRT-PCR. Ljo at 10(11) CFU/L induced a strong response in all chemokines examined. To assess the specific host-signaling pathways involved, we performed RT-PCR amplification of Toll-like receptors (TLR) and nucleotide-binding oligomerization domain-like receptors. TLR7 and TLR9 expression levels were induced 4.2- and 9-fold, respectively, whereas other TLR and nucleotide-binding oligomerization domain receptors were not modified. A similar effect was observed in Caco-2 monolayers treated with Ljo cell-free extract or purified nucleic acids (NA). Increased levels of IFN type 1 and IFN regulators Stat1 and IRF7 followed the upregulation of TLR9. Activation of TLR9 was also evidenced by increased Frizzled 5 expression in Ljo-treated Caco-2 cells and an increase in the number of Paneth cells in Ljo-fed, diabetes-prone rats. These results are in agreement with the polarizing-tolerizing mechanism recently described in which the apical stimulation of TLR9 in intestinal epithelial cells leads to a higher state of immunologic alertness. Furthermore, these results suggest that live probiotics could be, in the future, replaced with select cellular components.


Assuntos
Imunidade Inata , Lactobacillus/imunologia , Celulas de Paneth/citologia , Celulas de Paneth/imunologia , Probióticos , Receptor Toll-Like 9/metabolismo , Animais , Células CACO-2 , Contagem de Células , Quimiocinas/genética , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/prevenção & controle , Receptores Frizzled/genética , Humanos , Interferon-alfa/genética , Modelos Imunológicos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Endogâmicos BB , Transdução de Sinais , Receptor Toll-Like 9/genética , Receptores Toll-Like/genética , Receptores Toll-Like/metabolismo , Regulação para Cima
12.
Langmuir ; 26(19): 15339-44, 2010 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-20839779

RESUMO

Spreading of homogeneous mixtures of bottle-brush and linear macromolecules of poly(n-butylacrylate) on a solid substrate has been monitored on the molecular scale by atomic force microscopy. Despite the nearly identical chemical composition and similar molecular weight, brush-like macromolecules move markedly slower than linear chains. Moreover, smaller bottle-brushes have been shown to flow faster than the larger bottle-brushes, resulting in fractionation of the macromolecules along the spreading direction. This behavior was explained by the difference in sliding friction coefficient between the bottle-brush macromolecules and linear chains with the substrate. A theoretical model of molecular size separation is in a good agreement with experimental data.

13.
Xenotransplantation ; 17(3): 197-206, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20636540

RESUMO

BACKGROUND: The continued presence of a primate antibody-mediated response to cells and organs from alpha1,3-galactosyltransferase gene-knockout (GTKO) pigs indicates that there may be antigens other than Gal alpha 1,3Gal (alpha Gal) against which primates have xenoreactive antibodies. Human and baboon sera were tested for reactivity against a panel of saccharides that might be potential antigen targets for natural anti-non-alpha Gal antibodies. METHODS: Human sera (n = 16) and baboon sera (n = 15) of all ABO blood types were tested using an enzyme-linked immunoadsorbent assay for binding of IgM and IgG to a panel of synthetic polyacrylamide-linked saccharides (n = 15). Human sera were also tested after adsorption on alpha Gal immunoaffinity beads. Sera from healthy wild-type (WT, n = 6) and GTKO (n = 6) pigs and from baboons (n = 4) sensitized to GTKO pig organ or artery transplants (of blood type O) were also tested. Forssman antigen expression on baboon and pig tissues was investigated by immunohistochemistry. RESULTS: Both human and baboon sera showed high IgM and IgG binding to alpha Gal saccharides, alpha-lactosamine, and Forssman disaccharide. Human sera also demonstrated modest binding to N-glycolylneuraminic acid (Neu5Gc). When human sera were adsorbed on alpha Gal oligosaccharides, there was a reduction in binding to alpha Gal and alpha-lactosamine, but not to Forssman. WT and GTKO pig sera showed high binding to Forssman, and GTKO pig sera showed high binding to alpha Gal saccharides. Baboon sera sensitized to GTKO pigs showed no significant increased binding to any specific saccharide. Staining for Forssman was negative on baboon and pig tissues. CONCLUSIONS: We were unable to identify definitively any saccharides from the selected panel that may be targets for primate anti-non-alpha Gal antibodies. The high level of anti-Forssman antibodies in humans, baboons, and pigs, and the absence of Forssman expression on pig tissues, suggest that the Forssman antigen does not play a role in the primate immune response to pigs.


Assuntos
Anticorpos/imunologia , Antígenos/imunologia , Carboidratos/imunologia , Galactosiltransferases/genética , Papio/imunologia , Animais , Anticorpos/sangue , Antígenos/química , Carboidratos/química , Antígeno de Forssman/imunologia , Galactosiltransferases/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Camundongos , Oligossacarídeos/química , Oligossacarídeos/metabolismo , Papio/sangue , Baço/citologia , Baço/imunologia , Suínos , Distribuição Tecidual
14.
Oncoimmunology ; 9(1): 1811605, 2020 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-33224628

RESUMO

TGFß is a pleiotropic cytokine that may have both tumor inhibiting and tumor promoting properties, depending on tissue and cellular context. Emerging data support a role for TGFß in suppression of antitumor immunity. Here we show that SAR439459, a pan-TGFß neutralizing antibody, inhibits all active isoforms of human and murine TGFß, blocks TGFß-mediated pSMAD signaling, and TGFß-mediated suppression of T cells and NK cells. In vitro, SAR439459 synergized with anti-PD1 to enhance T cell responsiveness. In syngeneic tumor models, SAR439459 treatment impaired tumor growth, while the combination of SAR439459 with anti-PD-1 resulted in complete tumor regression and a prolonged antitumor immunity. Mechanistically, we found that TGFß inhibition with PD-1 blockade augmented intratumoral CD8+ T cell proliferation, reduced exhaustion, evoked proinflammatory cytokines, and promoted tumor-specific CD8+ T cell responses. Together, these data support the hypothesis that TGFß neutralization using SAR439459 synergizes with PD-1 blockade to promote antitumor immunity and formed the basis for the ongoing clinical investigation of SAR439459 in patients with cancer (NCT03192345).


Assuntos
Terapia de Imunossupressão , Receptor de Morte Celular Programada 1 , Animais , Anticorpos Monoclonais/farmacologia , Linhagem Celular Tumoral , Humanos , Tolerância Imunológica , Camundongos
15.
J Am Chem Soc ; 130(13): 4228-9, 2008 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-18327946

RESUMO

Adsorption-induced degradation of brushlike macromolecules was monitored through molecular imaging by atomic force microscopy. The rate constant for C-C bond cleavage was shown to be extremely sensitive to the substrate surface energy. A few percent increase in the surface energy from 69.2 to 71.2 mN/m led to an order of magnitude increase of the scission rate. The absolute values of the rupture forces ranging from 2.57 to 2.47 nN are in agreement with previously calculated and measured values for stretching surface-tethered molecules.

16.
J Clin Cell Immunol ; 7(5)2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27853628

RESUMO

OBJECTIVE: Establishing an effective humoral immunity is an important host defense mechanism in intestinal mucosa. T follicular helper (Tfh) cells are a spectrum of CXCR5 expressing T helper cells that induce antigen-specific B cell differentiation. Because the differentiation of T helper cells is largely regulated by innate immunity, we addressed whether TRIF signaling regulates Tfh cell differentiation and its ability to trigger humoral immune responses in the intestine. METHOD: CD4+CXCR5+ T cells, B cells, and plasma cells in the Peyer's patches (PPs) of WT and TRIF-deficient (TrifLPS2) mice were analyzed by flow cytometry at the baseline, 9 days post primary infection, and 7 days post-secondary infection with Y. enterocolitica. Y. enterocolitica-specific CD4+CXCR5+ T cells were generated in vitro by co-culturing peritoneal macrophages with splenic naïve T cells in the presence of Y. enterocolitica lysate. WT and TrifLPS2 mice received CD4+CXCR5+ T cells isolated either from Y. enterocolitica-primed WT mice or generated in vitro. These mice were infected with Y. enterocolitica and followed up to 4 weeks. Y. enterocolitica-specific IgA and IgG were measured in stool and serum samples, respectively. RESULTS: At baseline, CD4+CXCR5+ T cell proportion was higher but the proportion of B cells and plasma cells was lower in the PPs of TrifLPS2 mice compared to WT mice. After infection, the proportion of plasma cells also became higher in the PPs of TrifLPS2 mice compared to WT mice. Corresponding increase of Y. enterocolitica-specific stool IgA but not serum IgG was found in TrifLPS2 mice compared to WT mice. Both in vivo isolated and in vitro generated CD4+CXCR5+ T cells induced protective immunity against Y. enterocolitica infection. CONCLUSION: Our results reveal a novel role of TRIF in the regulation of humoral immunity in the intestine that can be utilized as a basis for a unique vaccine strategy.

17.
Int J Soc Psychiatry ; 50(2): 186-91, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15293435

RESUMO

BACKGROUND: Poor oral health has been reported among various psychiatric populations. Little is known regarding the oral health among psychiatric patients in Asia. AIMS: To examine the oral health status of a group of Chinese psychiatric in-patients in a long-term rehabilitation facility. METHODS: A dental survey using the WHO standardised dental evaluation form was conducted in adult psychiatric patients in a rehabilitation programme. A qualified dentist examined all consenting patients. RESULTS: Ninety-one patients (64.8% male; mean age: 44.7 +/- 9.9 years; mean length of illness: 20.3 +/- 11.5 years) were included in the study, the majority (80.2%) diagnosed with schizophrenia. Malocclusion was found in 79.1% of patients. The mean number of missing teeth was 9.5 +/- 8.9. Bleeding on probing, calculus, shallow and deep pockets were found in 7.1%, 71.8%, 72.9% and 28.2% of patients, respectively. Dental caries were found in 75.3% of dentate patients. The mean number of caries per patient was 5.5 +/- 6.1. Fifty-four per cent of patients needed dental extraction and 78.8% required conservative dental treatment. Older age and length of illness were significantly associated with poor dental health. CONCLUSIONS: Oral health status of chronic psychiatric patients seems to be considerably worse than that of the general population. Mental health professionals should pay more attention to preventive oral health habits of psychiatric patients.


Assuntos
Periodontite Agressiva/epidemiologia , Transtornos Mentais/etnologia , Saúde Bucal , Índice de Higiene Oral , Adolescente , Adulto , Idoso , Doença Crônica , Estudos Transversais , Feminino , Hong Kong/epidemiologia , Humanos , Masculino , Transtornos Mentais/epidemiologia , Pessoa de Meia-Idade , Boca Edêntula/epidemiologia
18.
Prim Dent Care ; 9(2): 57-61, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12024903

RESUMO

INTRODUCTION: The purpose of the study was to evaluate a recently introduced aesthetic restorative system in respect of: Presentation and organisation of the package. Its handling characteristics. Its polishability. Shade selection procedures and aesthetic outcome. MATERIAL AND METHOD: The material, Esthet.X Micro Matrix system (Dentsply), was evaluated by general dental practitioners from a clinical research group known as PEER (Product and Equipment Evaluation and Research). The evaluators were asked to use the material, following manufacturer's instructions, in a variety of cases. A questionnaire was designed specifically for this study and the questions were directed to both the dentists and their dental nurses. The results were analysed statistically and represented in visual analogue scales. RESULT: The material was found to be useful and generally well received. Its use was thought to be technique sensitive but good to excellent results can be achieved. Areas where the evaluators thought the product could be improved were also discussed.


Assuntos
Resinas Compostas/química , Restauração Dentária Permanente , Compostos de Alumínio/química , Silicatos de Alumínio/química , Atitude do Pessoal de Saúde , Bis-Fenol A-Glicidil Metacrilato/química , Cor , Polimento Dentário , Pesquisa em Odontologia , Restauração Dentária Permanente/classificação , Restauração Dentária Permanente/métodos , Embalagem de Medicamentos , Estética Dentária , Fluoretos/química , Odontologia Geral , Hong Kong , Humanos , Polietilenoglicóis/química , Ácidos Polimetacrílicos/química , Dióxido de Silício/química , Propriedades de Superfície , Inquéritos e Questionários
19.
Int J Dent ; 2014: 982071, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24648842

RESUMO

Objective. The objective of this research was to evaluate the caries control potential of a new fluoride mouthrinse that also contained antimicrobial agents and a biofilm disrupting agent using different in vitro models. Methods. Four in vitro studies were conducted to assess the performance of this three pronged approach to caries control: (1) traditional enamel fluoride uptake, (2) surface microhardness study using pH cycling model and subsequent fluoride uptake, (3) a salivary biofilm flow-through study to determine the anti-microbial activity, and (4) a single species biofilm model measuring effect on biofilm matrix disruption. Results. The data showed that a LISTERINE rinse with fluoride, essential oils and xylitol was superior in promoting enamel fluoride uptake and in enhancing antimicrobial activity over traditional commercially available fluoridated products. An increase of the surface microhardness was observed when the LISTERINE rinse was used in combination with fluoridated toothpaste versus the fluoridated toothpaste alone. Finally, it was demonstrated that xylitol solutions disrupted and reduced the biovolume of biofilm matrix of mature Streptococcus mutans. Conclusion. These in vitro studies demonstrated that a fluoride mouthrinse with antimicrobial agent and biofilm matrix disrupting agent provided multifaceted and enhanced anti-caries efficacy by promoting remineralization, reducing acidogenic bacteria and disrupting biofilm matrix.

20.
Cancer Discov ; 4(6): 662-673, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24675041

RESUMO

UNLABELLED: Non-small cell lung cancers (NSCLC) harboring anaplastic lymphoma kinase (ALK) gene rearrangements invariably develop resistance to the ALK tyrosine kinase inhibitor (TKI) crizotinib. Herein, we report the first preclinical evaluation of the next-generation ALK TKI, ceritinib (LDK378), in the setting of crizotinib resistance. An interrogation of in vitro and in vivo models of acquired resistance to crizotinib, including cell lines established from biopsies of patients with crizotinib-resistant NSCLC, revealed that ceritinib potently overcomes crizotinib-resistant mutations. In particular, ceritinib effectively inhibits ALK harboring L1196M, G1269A, I1171T, and S1206Y mutations, and a cocrystal structure of ceritinib bound to ALK provides structural bases for this increased potency. However, we observed that ceritinib did not overcome two crizotinib-resistant ALK mutations, G1202R and F1174C, and one of these mutations was identified in 5 of 11 biopsies from patients with acquired resistance to ceritinib. Altogether, our results demonstrate that ceritinib can overcome crizotinib resistance, consistent with clinical data showing marked efficacy of ceritinib in patients with crizotinib-resistant disease. SIGNIFICANCE: The second-generation ALK inhibitor ceritinib can overcome several crizotinib-resistant mutations and is potent against several in vitro and in vivo laboratory models of acquired resistance to crizotinib. These findings provide the molecular basis for the marked clinical activity of ceritinib in patients with ALK-positive NSCLC with crizotinib-resistant disease. Cancer Discov; 4(6); 662-73. ©2014 AACR. See related commentary by Ramalingam and Khuri, p. 634 This article is highlighted in the In This Issue feature, p. 621.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/uso terapêutico , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Sulfonas/uso terapêutico , Quinase do Linfoma Anaplásico , Animais , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Crizotinibe , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos , Camundongos SCID , Mutação , Pirazóis/uso terapêutico , Piridinas/uso terapêutico , Receptores Proteína Tirosina Quinases/genética , Receptores Proteína Tirosina Quinases/metabolismo , Carga Tumoral
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