Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
Astrobiology ; 24(4): 343-370, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38452176

RESUMO

Long-standing unexplained Venus atmosphere observations and chemical anomalies point to unknown chemistry but also leave room for the possibility of life. The unexplained observations include several gases out of thermodynamic equilibrium (e.g., tens of ppm O2, the possible presence of PH3 and NH3, SO2 and H2O vertical abundance profiles), an unknown composition of large, lower cloud particles, and the "unknown absorber(s)." Here we first review relevant properties of the venusian atmosphere and then describe the atmospheric chemical anomalies and how they motivate future astrobiology missions to Venus.


Assuntos
Vênus , Exobiologia , Meio Ambiente Extraterreno , Gases/química , Atmosfera/química
2.
Int J Clin Pediatr Dent ; 14(4): 447-453, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34824494

RESUMO

BACKGROUND AND AIM OF THE STUDY: Pediatric patients are apprehensive regarding having dental treatment mainly because of painful local anesthetic (LA) injections. Various techniques like transcutaneous electrical nerve stimulation (TENS), topical anesthetic agents, and vibrator device are introduced to reduce discomfort before LA administration. Therefore, the present study aimed to compare and evaluate the effectiveness of TENS, 2% lignocaine gel, eutectic mixture of lignocaine and prilocaine (EMLA), and vibrating device before LA injections in alleviating pain in pediatric patients. MATERIALS AND METHODS: Sixty healthy children aged 6 to 12 years who required LA injections for dental procedures were selected and divided into four groups with 15 patients in each group. Wong-Baker's facial pain rating scale (WBFPRS) and face, legs, activity, cry, and consolability scale (FLACC) are used for pain perception which are tabulated, and statistically analyzed. RESULTS: The test results demonstrated that the TENS group has shown the least mean WBFPRS and FLACC score, followed by vibrator devices, EMLA gel, and lignocaine gel. CONCLUSION: The newly introduced TENS apparatus showed encouraging results, hence can be used as a safe and reliable technique to be used in pediatric dentistry. HOW TO CITE THIS ARTICLE: Patil SB, Popali DD, Bondarde PA, et al. Comparative Evaluation of the Effectiveness of Different Pain-alleviating Methods before Local Anesthetic Administration in Children of 6 to 12 Years of Age: A Clinical Study. Int J Clin Pediatr Dent 2021;14(4):447-453.

3.
J Allergy Clin Immunol ; 146(3): 555-570, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32320734

RESUMO

BACKGROUND: Allergic asthmatic subjects are uniquely susceptible to acute wheezing episodes provoked by rhinovirus. However, the underlying immune mechanisms and interaction between rhinovirus and allergy remain enigmatic, and current paradigms are controversial. OBJECTIVE: We sought to perform a comprehensive analysis of type 1 and type 2 innate and adaptive responses in allergic asthmatic subjects infected with rhinovirus. METHODS: Circulating virus-specific TH1 cells and allergen-specific TH2 cells were precisely monitored before and after rhinovirus challenge in allergic asthmatic subjects (total IgE, 133-4692 IU/mL; n = 28) and healthy nonallergic controls (n = 12) using peptide/MHCII tetramers. T cells were sampled for up to 11 weeks to capture steady-state and postinfection phases. T-cell responses were analyzed in parallel with 18 cytokines in the nose, upper and lower airway symptoms, and lung function. The influence of in vivo IgE blockade was also examined. RESULTS: In uninfected asthmatic subjects, higher numbers of circulating virus-specific PD-1+ TH1 cells, but not allergen-specific TH2 cells, were linked to worse lung function. Rhinovirus infection induced an amplified antiviral TH1 response in asthmatic subjects versus controls, with synchronized allergen-specific TH2 expansion, and production of type 1 and 2 cytokines in the nose. In contrast, TH2 responses were absent in infected asthmatic subjects who had normal lung function, and in those receiving anti-IgE. Across all subjects, early induction of a minimal set of nasal cytokines that discriminated high responders (G-CSF, IFN-γ, TNF-α) correlated with both egress of circulating virus-specific TH1 cells and worse symptoms. CONCLUSIONS: Rhinovirus induces robust TH1 responses in allergic asthmatic subjects that may promote disease, even after the infection resolves.


Assuntos
Asma/imunologia , Hipersensibilidade/imunologia , Infecções por Picornaviridae/imunologia , Rhinovirus/fisiologia , Células Th1/imunologia , Células Th2/imunologia , Alérgenos/imunologia , Antígenos Virais/imunologia , Células Cultivadas , Citocinas/metabolismo , Suscetibilidade a Doenças , Humanos , Ativação Linfocitária , Receptor de Morte Celular Programada 1/metabolismo , Sons Respiratórios
4.
Indian J Otolaryngol Head Neck Surg ; 71(Suppl 1): 79-81, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31741936

RESUMO

Double ectopic thyroid tissue is a rare phenomenon. We report a case of a 75-year-old man who was referred with two painless swellings in the anterior midline of neck with a tracheostomy tube in situ with the suspicion of malignancy. Such patients should be investigated completely prior to definitive treatment.

5.
J Allergy Clin Immunol ; 141(6): 2048-2060.e13, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-28939412

RESUMO

BACKGROUND: The pathogenesis of severe asthma in childhood remains poorly understood. OBJECTIVE: We sought to construct the immunologic landscape in the airways of children with severe asthma. METHODS: Comprehensive analysis of multiple cell types and mediators was performed by using flow cytometry and a multiplex assay with bronchoalveolar lavage (BAL) specimens (n = 68) from 52 highly characterized allergic and nonallergic children (0.5-17 years) with severe treatment-refractory asthma. Multiple relationships were tested by using linear mixed-effects modeling. RESULTS: Memory CCR5+ TH1 cells were enriched in BAL fluid versus blood, and pathogenic respiratory viruses and bacteria were readily detected. IFN-γ+IL-17+ and IFN-γ-IL-17+ subsets constituted secondary TH types, and BAL fluid CD8+ T cells were almost exclusively IFN-γ+. The TH17-associated mediators IL-23 and macrophage inflammatory protein 3α/CCL20 were highly expressed. Despite low TH2 numbers, TH2 cytokines were detected, and TH2 skewing correlated with total IgE levels. Type 2 innate lymphoid cells and basophils were scarce in BAL fluid. Levels of IL-5, IL-33, and IL-28A/IFN-λ2 were increased in multisensitized children and correlated with IgE levels to dust mite, ryegrass, and fungi but not cat, ragweed, or food sources. Additionally, levels of IL-5, but no other cytokine, increased with age and correlated with eosinophil numbers in BAL fluid and blood. Both plasmacytoid and IgE+FcεRI+ myeloid dendritic cells were present in BAL fluid. CONCLUSIONS: The lower airways of children with severe asthma display a dominant TH1 signature and atypical cytokine profiles that link to allergic status. Our findings deviate from established paradigms and warrant further assessment of the pathogenicity of TH1 cells in patients with severe asthma.


Assuntos
Asma/imunologia , Células Th1/imunologia , Adolescente , Asma/complicações , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Criança , Pré-Escolar , Feminino , Humanos , Hipersensibilidade/complicações , Hipersensibilidade/imunologia , Lactente , Pulmão/imunologia , Masculino
7.
J Radiol Case Rep ; 8(4): 25-31, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24967032

RESUMO

We report a rare clinical presentation of renal cell carcinoma in the form of small bowel obstruction which was secondary to a metastatic ileal intussusception. Intussusception in the elderly is most commonly due to an underlying neoplasm, however metastases from a renal cell carcinoma is very uncommon. We present clinical details, radiological and pathological findings of the case followed by a discussion of the diagnosis and management of intussusception in the adult population.


Assuntos
Carcinoma de Células Renais/complicações , Carcinoma de Células Renais/secundário , Doenças do Íleo/etiologia , Neoplasias do Íleo/complicações , Neoplasias do Íleo/secundário , Intussuscepção/etiologia , Neoplasias Renais/patologia , Carcinoma de Células Renais/diagnóstico por imagem , Humanos , Doenças do Íleo/diagnóstico por imagem , Neoplasias do Íleo/diagnóstico por imagem , Intussuscepção/diagnóstico por imagem , Neoplasias Renais/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Intensificação de Imagem Radiográfica , Tomografia Computadorizada por Raios X
8.
Curr Allergy Asthma Rep ; 14(5): 433, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24633617

RESUMO

Atopic dermatitis (AD) is a chronic inflammatory skin condition with complex etiology that is dependent upon interactions between the host and the environment. Acute skin lesions exhibit the features of a Th2-driven inflammatory disorder, and many patients are highly atopic. The skin barrier plays key roles in immune surveillance and homeostasis, and in preventing penetration of microbial products and allergens. Defects that compromise the structural integrity or else the immune function of the skin barrier play a pivotal role in the pathogenesis of AD. This article provides an overview of the array of molecular building blocks that are essential to maintaining healthy skin. The basis for structural defects in the skin is discussed in relation to AD, with an emphasis on filaggrin and its genetic underpinnings. Aspects of innate immunity, including the role of antimicrobial peptides and proteases, are also discussed.


Assuntos
Dermatite Atópica/imunologia , Pele/imunologia , Animais , Dermatite Atópica/tratamento farmacológico , Dermatite Atópica/fisiopatologia , Proteínas Filagrinas , Humanos , Bicamadas Lipídicas/imunologia , Peptídeo Hidrolases/imunologia , Inibidores de Proteases/uso terapêutico , Pele/fisiopatologia , Junções Íntimas/imunologia
9.
J Allergy Clin Immunol ; 133(4): 952-60, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24084078

RESUMO

The cytokines IL-4, IL-13, and thymic stromal lymphopoietin play a key role in allergic disease by virtue of their ability to initiate, maintain, and augment TH2 responses. These molecules mediate their effects through type 1 cytokine receptors, which bind cytokines with a characteristic structure. Receptors are expressed on a broad array of immune cell types and are integral to complex cytokine networks operating in health and disease. TH2-promoting cytokines bind different configurations of receptors. Receptor subunits can exist in surface-bound or soluble forms, as well as in isolation or in partnership with other subunits. Sharing of receptor subunits among different cytokine receptor complexes adds to the intricate landscape. This article describes the characteristics of receptors for IL-4, IL-13, and thymic stromal lymphopoietin and their respective ligands from a structure-function perspective. We detail the mechanisms of receptor complex assembly, the interrelated nature of these receptors, and the effect on allergic inflammation. The ability for novel and atypical types of receptors to modulate inflammatory processes is also discussed. We highlight current and emerging treatments that target TH2-promoting receptor complexes. Understanding the molecular features of these receptors provides insight into different disease phenotypes and the variable clinical outcomes arising from targeted therapies. These considerations can be used to inform future directions for research and creative strategies for treating individual patients.


Assuntos
Hipersensibilidade/imunologia , Hipersensibilidade/metabolismo , Receptores de Citocinas/metabolismo , Células Th2/imunologia , Células Th2/metabolismo , Animais , Citocinas/química , Citocinas/metabolismo , Humanos , Ligação Proteica , Mapas de Interação de Proteínas , Receptores de Citocinas/química , Transdução de Sinais
10.
Front Immunol ; 4: 461, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24381572

RESUMO

BACKGROUND: Shortly after allergen exposure, the number of bone marrow (BM) and circulating CD34(+) progenitors increases. We aim to analyze the possible mechanism whereby the allergic reaction stimulates BM to release these effector cells in increased numbers. We hypothesize that mast cells (MCs) may play a predominant role in this process. OBJECTIVE: To examine the effect of IgE-activated MCs on BM mesenchymal stromal cells which regulate proliferation and differentiation of CD34(+) progenitors. METHODS: Primary MCs were derived from CD34(+) precursors and activated with IgE/anti-IgE. BM mesenchymal stromal cells were co-cultured with CD34(+) progenitor cells and stimulated with IL-1/TNF or IgE/anti-IgE-activated MCs in Transwell system. RESULTS: BM mesenchymal stromal cells produce low level of thymic stromal lymphopoietin (TSLP) under steady state conditions, which is markedly increased by stimulation with proinflammatory cytokines IL-1 and TNF or IgE-activated MCs. The latter also triggers bone marrow-derived mesenchymal stromal cells production of G-CSF, and GM-CSF while inhibiting SDF-1. MC-activated mesenchymal stromal cells stimulate CD34(+) cells to proliferate and to regulate their expression of early allergy-associated genes. CONCLUSION AND CLINICAL RELEVANCE: This in vitro study indicates that IgE-activated MCs trigger BM mesenchymal stromal cells to release TSLP and hematopoietic growth factors and to regulate the proliferation and lineage commitment of CD34(+) precursor cells. The data predict that the effective inhibition of MCs should impair mobilization and accumulation of allergic effector cells and thereby reduce the severity of allergic diseases.

12.
Free Radic Biol Med ; 51(10): 1903-9, 2011 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-21925592

RESUMO

Oxidative tissue damage is a hallmark of many chronic inflammatory diseases. However, the precise mechanisms linking oxidative changes to inflammatory reactions remain unclear. Herein we show that Toll-like receptor 2 (TLR2) translates oxidative tissue damage into inflammatory responses by mediating the effects of oxidized phospholipids. Intraperitoneal injection of oxidized 1-palmitoyl-2-arachidonyl-sn-3-glycerophosphorylcholine (OxPAPC) resulted in upregulation of inflammatory genes in wild-type, but not in TLR2(-/-) mice. In vitro, OxPAPC induced TLR2 (but not TLR4)-dependent inflammatory gene expression and JNK and p38 signaling in macrophages. Induction of TLR2-dependent gene expression required reducible functional groups on sn-2 acyl chains of oxidized phospholipids, as well as serum cofactors. Finally, TLR2(-/-) mice were protected against carbon tetrachloride-induced oxidative tissue damage and inflammation, which was accompanied by accumulation of oxidized phospholipids in livers. Together, our findings demonstrate that TLR2 mediates cellular responses to oxidative tissue damage and they provide new insights into how oxidative stress is linked to acute and chronic inflammation.


Assuntos
Intoxicação por Tetracloreto de Carbono/imunologia , Macrófagos Peritoneais/efeitos dos fármacos , Receptor 2 Toll-Like/metabolismo , Animais , Intoxicação por Tetracloreto de Carbono/genética , Intoxicação por Tetracloreto de Carbono/metabolismo , Células Cultivadas , Imuno-Histoquímica , Inflamação , Receptores de Lipopolissacarídeos/genética , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/genética , Sistema de Sinalização das MAP Quinases/imunologia , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/metabolismo , Macrófagos Peritoneais/patologia , Camundongos , Camundongos Knockout , Fosfatidilcolinas/administração & dosagem , Fosfatidilcolinas/efeitos adversos , Fosfatidilcolinas/sangue , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/imunologia , Receptor 4 Toll-Like/genética
13.
Curr Probl Dermatol ; 41: 112-124, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21576952

RESUMO

Regulatory T (T(reg)) cells play a pivotal role in immune suppression and are integral to the control of allergic responses. The chronic inflammatory skin condition atopic dermatitis (AD) is severest in patients who are sensitized to allergens from diverse sources including foods, pollens and animal danders, as well as skin-colonizing organisms. These individuals typically present with eczematous skin eruptions in early childhood, and evolution of the disease is thought to reflect an underlying dysregulated T-cell response to allergens that manifests as a Th2 response. Studying T(reg) cells in the context of AD from infancy into adulthood could yield insight into their role in disease pathogenesis and reveal new strategies for exploiting these cells for therapeutic purposes. Such studies are challenging in humans owing to the heterogeneous nature of T(reg) cells, lack of a reliable surface marker, and the paucity of knowledge surrounding the emergence of specialized T cells in early life. Moreover, the blurred distinction between activated effector T cells and T(reg) cells further complicates studies in the context of inflammatory disorders such as AD. There is emerging evidence to suggest that T(reg) cells can convert to Th2 cells and that this pathway is bidirectional. This phenomenon may be a double-edged sword with important implications not only for subverting T(reg) cells in disease, but also for potential treatments designed to amplify these cells in order to suppress the allergic inflammatory cascade in AD.


Assuntos
Dermatite Atópica/imunologia , Linfócitos T Reguladores/imunologia , Alérgenos/imunologia , Biomarcadores/metabolismo , Dermatite Atópica/etiologia , Dermatite Atópica/terapia , Fatores de Transcrição Forkhead/metabolismo , Humanos , Hipersensibilidade/etiologia , Hipersensibilidade/imunologia , Mediadores da Inflamação/metabolismo , Modelos Imunológicos , Linfócitos T Reguladores/metabolismo , Células Th2/imunologia
14.
J Cell Biochem ; 104(3): 953-64, 2008 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-18189269

RESUMO

TULA belongs to a two-member family: TULA (STS-2) is a lymphoid protein, whereas STS-1/TULA-2 is expressed ubiquitously. TULA proteins were implicated in the regulation of signaling mediated by protein tyrosine kinases (PTKs). The initial experiments did not fully reveal the molecular mechanism of these effects, but suggested that both TULA proteins act in a similar fashion. It was shown recently that STS-1/TULA-2 dephosphorylates PTKs. In this study, we analyzed the effects of TULA proteins on Syk, a PTK playing an important role in lymphoid signaling. First, we have shown that TULA-2 decreases tyrosine phosphorylation of Syk in vivo and in vitro and that the intact phosphatase domain of TULA-2 is essential for this effect. We have also shown that TULA-2 exhibits a certain degree of substrate specificity. Our results also indicate that inactivated TULA-2 increases tyrosine phosphorylation of Syk in cells co-transfected to overexpress these proteins, thus acting as a dominant-negative form that suppresses dephosphorylation of Syk caused by endogenous TULA-2. Furthermore, we have demonstrated that phosphatase activity of TULA is negligible as compared to that of TULA-2 and that this finding correlates with an increase in Syk tyrosine phosphorylation in cells overexpressing TULA. This result is consistent with the dominant-negative effect of inactivated TULA-2, arguing that TULA acts in this system as a negative regulator of TULA-2-dependent dephosphorylation. To summarize, our findings indicate that TULA proteins may exert opposite effects on PTK-mediated signaling and suggest that a regulatory mechanism based on this feature may exist.


Assuntos
Proteínas de Transporte/metabolismo , Regulação da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Tirosina Quinases/metabolismo , Linhagem Celular , Dimerização , Genes Dominantes , Humanos , Proteínas de Membrana , Modelos Biológicos , Modelos Genéticos , Fosforilação , Processamento de Proteína Pós-Traducional , Proteínas Tirosina Fosfatases , Transdução de Sinais , Especificidade por Substrato , Quinase Syk , Tirosina/química
15.
Oncogene ; 23(27): 4690-706, 2004 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-15107835

RESUMO

Downregulation of protein tyrosine kinases is a major function of the multidomain protein c-Cbl. This effect of c-Cbl is critical for both negative regulation of normal physiological stimuli and suppression of cellular transformation. In spite of the apparent importance of these effects of c-Cbl, their own regulation is poorly understood. To search for possible novel regulators of c-Cbl, we purified a number of c-Cbl-associated proteins by affinity chromatography and identified them by mass spectrometry. Among them, we identified the UBA- and SH3-containing protein T-cell Ubiquitin LigAnd (TULA), which can also bind to ubiquitin. Functional studies in a model system based on co-expression of TULA, c-Cbl, and EGF receptor in 293T cells demonstrate that TULA is capable of inhibiting c-Cbl-mediated downregulation of EGF receptor. Furthermore, modulation of TULA concentration in Jurkat T-lymphoblastoid cells demonstrates that TULA upregulates the activity of both Zap kinase and NF-AT transcription factor. Therefore, our study indicates that TULA counters the inhibitory effect of c-Cbl on protein tyrosine kinases and, thus, may be involved in the regulation of biological effects of c-Cbl. Finally, our results suggest that TULA-mediated inhibition of the effects of c-Cbl on protein tyrosine kinases is caused by TULA-induced ubiquitylation and degradation of c-Cbl.


Assuntos
Proteínas Proto-Oncogênicas/metabolismo , Linfócitos T/metabolismo , Ubiquitina-Proteína Ligases/química , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina/metabolismo , Substituição de Aminoácidos , Animais , Sequência de Bases , Células COS , Linhagem Celular Tumoral , Chlorocebus aethiops , Regulação para Baixo , Receptores ErbB/antagonistas & inibidores , Regulação Neoplásica da Expressão Gênica , Células HL-60 , Células HeLa , Humanos , Células Jurkat , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Ligação Proteica , Estrutura Terciária de Proteína , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas/química , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/isolamento & purificação , Proteínas Proto-Oncogênicas c-cbl , RNA Interferente Pequeno/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Frações Subcelulares/metabolismo , Compostos de Sulfidrila/química , Distribuição Tecidual , Fatores de Transcrição/metabolismo , Células U937 , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/isolamento & purificação
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA