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1.
J Exp Med ; 193(1): 123-33, 2001 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11136826

RESUMO

Human mast cells (hMCs) derived in vitro from cord blood mononuclear cells exhibit stem cell factor (SCF)-dependent comitogenic responses to T helper cell type 2 (Th2) cytokines. As cysteinyl leukotriene (cys-LT) biosynthesis is a characteristic of immunoglobulin (Ig)E-activated mucosal hMCs, we speculated that Th2 cytokines might regulate eicosanoid generation by hMCs. After passive sensitization for 5 d with IgE in the presence of SCF, anti-IgE-stimulated hMCs elaborated minimal cys-LT (0.1 +/- 0.1 ng/10(6) hMCs) and abundant prostaglandin (PG)D(2) (16.2 +/- 10.3 ng/10(6) hMCs). Priming of hMCs by interleukin (IL)-4 with SCF during passive sensitization enhanced their anti-IgE-dependent histamine exocytosis and increased their generation of both cys-LT (by 27-fold) and PGD(2) (by 2. 5-fold). Although priming with IL-3 or IL-5 alone for 5 d with SCF minimally enhanced anti-IgE-mediated cys-LT generation, these cytokines induced further six- and fourfold increases, respectively, in IgE-dependent cys-LT generation when provided with IL-4 and SCF; this occurred without changes in PGD(2) generation or histamine exocytosis relative to hMCs primed with IL-4 alone. None of these cytokines, either alone or in combination, substantially altered the levels of cytosolic phospholipase A(2) (cPLA(2)), 5-lipoxygenase (5-LO), or 5-LO activating protein (FLAP) protein expression by hMCs. In contrast, IL-4 priming dramatically induced the steady-state expression of leukotriene C(4) synthase (LTC(4)S) mRNA within 6 h, and increased the expression of LTC(4)S protein and functional activity in a dose- and time-dependent manner, with plateaus at 10 ng/ml and 5 d, respectively. Priming by either IL-3 or IL-5, with or without IL-4, supported the localization of 5-LO to the nucleus of hMCs. Thus, different Th2-derived cytokines target distinct steps in the 5-LO/LTC(4)S biosynthetic pathway (induction of LTC(4)S expression and nuclear import of 5-LO, respectively), each of which is necessary for a full integrated functional response to IgE-dependent activation, thus modulating the effector phenotype of mature hMCs.


Assuntos
Cisteína/biossíntese , Citocinas/farmacologia , Glutationa Transferase/biossíntese , Imunoglobulina E/metabolismo , Leucotrienos/biossíntese , Mastócitos/imunologia , Células Th2/imunologia , Araquidonato 5-Lipoxigenase/metabolismo , Núcleo Celular/enzimologia , Citocinas/fisiologia , Sangue Fetal/citologia , Sangue Fetal/imunologia , Humanos , Técnicas In Vitro , Recém-Nascido , Interleucina-3/farmacologia , Interleucina-5/farmacologia , Mastócitos/efeitos dos fármacos , Mastócitos/enzimologia , Prostaglandina D2/biossíntese , Fator de Células-Tronco/farmacologia
2.
Artigo em Inglês | MEDLINE | ID: mdl-20815311

RESUMO

BACKGROUND: Solidago virgaurea (goldenrod) is a perennial weed from which no allergens have been identified. A high latex content in its leaves has been reported. Although not an airborne allergen, it may be an important occupational sensitizer. OBJECTIVE: To identify allergenic proteins in goldenrod and to determine whether they cross-react with Hevea brasiliensis latex. METHODS: Potential cross-reactive allergens in latex and goldenrod were investigated by immunoblot inhibition and ImmunoCAP inhibition analyses using serum from patients with clinically evident goldenrod and/or latex allergy. Cross reactivity between latex allergens and goldenrod proteins was studied using recombinant Hev b 1, 3, 4, 5, 6.01, 6.02, 8, 9, or 11 in ImmunoCAP inhibition analyses. RESULTS: Immunoglobulin (Ig) E antibodies from individuals with goldenrod allergy bound extracted goldenrod proteins ranging from 20 kDa to 130 kDa in Western blots. Evidence for latex and goldenrod cross reactivity was identified by ImmunoCAP and immunoblot inhibition experiments using serum from patients with strongly positive concomitant latex and goldenrod-specific IgE antibody responses. Observed latex-goldenrod cross reactivity could not be ascribed to any of the recombinant major latex allergens evaluated. CONCLUSIONS: H brasiliensis latex and goldenrod contain cross-reactive and unique allergenic proteins. Exposure to goldenrod may sensitize patients to latex and vice versa.


Assuntos
Antígenos de Plantas/imunologia , Reações Cruzadas/imunologia , Epitopos/imunologia , Hipersensibilidade ao Látex/imunologia , Rinite Alérgica Sazonal/imunologia , Ligação Competitiva , Western Blotting , Feminino , Pessoal de Saúde , Hevea/imunologia , Humanos , Imunoglobulina E/sangue , Hipersensibilidade ao Látex/sangue , Hipersensibilidade ao Látex/diagnóstico , Pessoa de Meia-Idade , Exposição Ocupacional/efeitos adversos , Rinite Alérgica Sazonal/sangue , Rinite Alérgica Sazonal/diagnóstico , Solidago/imunologia
3.
J Biomed Mater Res B Appl Biomater ; 80(1): 211-9, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16850477

RESUMO

This study investigated the bacterial inactivation/sterilization effects of a new atmospheric plasma source, which is a brush-shaped argon glow discharge created under 1 atm pressure. Such an atmospheric plasma brush requires extremely low power of less than 20 W to operate; and therefore is essentially a low-temperature discharge as confirmed by gas-phase temperature measurements. Two bacteria, Escherichia coli (E. coli) and Micrococcus luteus (M. luteus), seeded in various media were subjected to plasma treatment and their survivability was examined. It was found that such argon atmospheric plasma brush is very effective in destruction of the bacteria cells. With nutrient broth and standard methods agar as supporting media, a cell reduction in a level of 6 orders of magnitude was observed for E. coli within 3-4 min plasma treatment. A similar level of cell reduction was also observed for M. luteus in the two media with 2 or 3 min plasma treatment. The plasma treatment effects on the bacteria cell structures were also examined using scanning electron microscopy and the cell structure damages due to the plasma exposure were observed on both bacteria. The possible sterilization mechanism of the argon plasmas is also discussed in this article.


Assuntos
Argônio/química , Contaminação de Equipamentos/prevenção & controle , Escherichia coli/crescimento & desenvolvimento , Micrococcus luteus/crescimento & desenvolvimento , Esterilização , Escherichia coli/ultraestrutura , Infecções por Escherichia coli/prevenção & controle , Temperatura Alta , Viabilidade Microbiana , Micrococcus luteus/ultraestrutura , Microscopia Eletrônica de Varredura , Esterilização/instrumentação , Esterilização/métodos , Fatores de Tempo
4.
J Anim Sci ; 95(3): 1288-1300, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28380507

RESUMO

Two 28-d experiments were conducted to evaluate the effects of extrusion of ground yellow corn, solvent-extracted soybean meal (SBM), and cracked whole soybeans (CWS) individually or as corn-soybean product blends on growth performance of weanling pigs. For Exp. 1, ground corn, SBM, and the corn-SBM blend were extruded at 137.5°C, 131.5°C, and 135.0°C, respectively, in a twin-screw extruder. Transit time was 60 s. Water was injected at 125 gmin during extrusion. The 5 treatments were the corn-SBM control diet and the diets with extruded (EX) corn + SBM, EX-SBM + corn, EX-corn + EX-SBM, and the EX-blend of corn-SBM. Ninety crossbred pigs with an initial average BW of 5.98 kg were allotted to 9 treatment replications with a barrow and gilt per pen. For Exp. 2, ground corn was preconditioned with water (10.0% of corn weight), and SBM was preconditioned with water and soybean oil (each at 20.0% of SBM weight) before extrusion. Raw CWS were not preconditioned. The corn, SBM, CWS, corn-SBM blend, and corn-CWS blend were extruded at 113.0°C, 132.0°C, 132.0°C, 88.0°C, and 102°C, respectively, with a single-screw extruder. Transit time was 30 s. The 8 isocaloric treatments were the corn-SBM control diet and the diets with EX-corn + SBM, EX-SBM + corn, EX-corn + EX-SBM, the EX-blend of corn-SBM, EX-CWS + corn, EX-CWS + EX-corn, and the EX-blend of corn-CWS. A total of 296 crossbred pigs with an initial average BW of 6.56 kg were allotted to 10 treatment replications. Sex and pigs per pen (3 or 4) were equalized within replication. Results for both experiments indicate that single- or twin-screw extrusion of ground corn or SBM as individual ingredients or as corn-SBM blends in diets for weanling pigs did not improve 28-d growth performance. However, for Exp. 2 weanling pigs fed the diets with EX-CWS + corn and EX-CWS + EX-corn had greater ( < 0.01) ADG and G:F, respectively, than pigs fed the corn-SBM control diet. The extrusion temperature of 102°C for the corn-CWS blend did not inactivate adequate protease inhibitors in CWS, and pigs fed that diet had poor growth performance. In conclusion, single-screw extrusion of CWS (132°C for 30 s) in diets for weanling pigs improved growth performance compared with pigs fed the corn-SBM control diet. However, twin- or single-screw extrusion of ground yellow corn or solvent-extracted SBM as individual ingredients or as corn-SBM blends in diets for weanling pigs did not improve growth performance compared with pigs fed the corn-SBM control diets.


Assuntos
Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Dieta/veterinária , Suínos/fisiologia , Animais , Peso Corporal , Feminino , Masculino , Óleo de Soja , Glycine max , Zea mays
5.
Artigo em Inglês | MEDLINE | ID: mdl-22255660

RESUMO

Epidural stimulation to trigger locomotion is a promising treatment after spinal cord injury (SCI). Continuous stimulation during locomotion is the conventional method. To improve recovery, we tested an innovative robot-driven epidural stimulation method, combined with a trunk-based neurorobotic system. The system was tested in rat, and the results were compared with the results of the neurorobotic therapy combined with the conventional epidural stimulation method. The rats had better recovery after treatment with the robot-driven epidural stimulation than conventional stimulation in our neurorobotic rehabilitation system.


Assuntos
Terapia por Estimulação Elétrica/métodos , Espaço Epidural/fisiopatologia , Transtornos Neurológicos da Marcha/fisiopatologia , Transtornos Neurológicos da Marcha/reabilitação , Recuperação de Função Fisiológica/fisiologia , Traumatismos da Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/reabilitação , Animais , Transtornos Neurológicos da Marcha/complicações , Ratos , Traumatismos da Medula Espinal/complicações , Resultado do Tratamento
6.
J Food Sci ; 74(2): E39-45, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19323740

RESUMO

High moisture extrusion has been used to produce vegetable meat analogues that resemble real animal meat and can provide significant health benefits. Since visual and textural properties are key factors for consumer acceptance, assessing fiber formation in the extruded products is important for quality control purpose. Recently, we developed a nondestructive photon migration method to quantify fiber formation in meat analogues. In this study, we implemented this technique in a real-time optical scanning system. This system can scan the entire sample area in real-time and provide 2-dimensional maps to visualize the degree of fiber formation and fiber orientation in the sample. The new system has a potential to provide a fast, nondestructive means for online monitoring of the fiber formation in meat analogues.


Assuntos
Carne/análise , Carne/normas , Lasers , Produtos da Carne/análise , Produtos da Carne/normas , Controle de Qualidade , Proteínas de Soja/análise , Proteínas de Soja/química , Espectrometria de Fluorescência
7.
Proc Natl Acad Sci U S A ; 102(40): 14380-5, 2005 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-16186496

RESUMO

Mast cells (MCs) are found in increased numbers at airway mucosal surfaces in asthmatic patients. Because human airway epithelial cells (HAECs) actively participate in airway inflammatory responses and are in direct contact with MCs in the mucosa, we hypothesized that HAEC-MC interactions may contribute to the differentiation and survival of MCs in the airway mucosa. Here, we show that HAECs express mRNA and protein for soluble and membrane-bound stem cell factor, releasing soluble stem cell factor into the cell culture supernatant at a concentration of 5.9 +/- 0.1 ng per 10(6) HAEC. HAECs were able to support MC survival in coculture in the absence of any exogenous cytokines for at least 4 d. Before the initiation of coculture, MCs were uniformly tryptase and chymase (MC(TC)) double positive, but by 2 d of coculture the majority of MCs expressed tryptase (MC(T)) alone. MCs supported in coculture generated low amounts of cysteinyl-leukotrienes (cys-LT) after FcepsilonRI-dependent activation (0.2 +/- 0.1 ng of cys-LT per 10(6) cells) and required priming with IL-4 and IL-3 during coculture to achieve a quantity of cys-LT generation within the range expected for human lung mucosal MC (26.5 +/- 16 ng of cys-LT per 10(6) cells). In these culture conditions, HAECs were able to direct mucosal MC protease phenotype, but T cell-derived Th2 cytokines were required for the expression of a functional airway MC eicosanoid phenotype. Thus, distinct cell types may direct unique aspects of reactive mucosal MC phenotype in the airways.


Assuntos
Diferenciação Celular/fisiologia , Mastócitos/fisiologia , Fenótipo , Mucosa Respiratória/metabolismo , Análise de Variância , Técnicas de Cultura de Células , Diferenciação Celular/imunologia , Sobrevivência Celular/imunologia , Sobrevivência Celular/fisiologia , Quimases , Cisteína/metabolismo , Citocinas/metabolismo , Primers do DNA , Ensaio de Imunoadsorção Enzimática , Humanos , Imuno-Histoquímica , Leucotrienos/metabolismo , Mastócitos/metabolismo , Mucosa Respiratória/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Serina Endopeptidases/metabolismo , Fator de Células-Tronco/metabolismo , Fatores de Tempo , Triptases
8.
Appl Environ Microbiol ; 36(2): 284-90, 1978 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16345308

RESUMO

The treatment of a hardwood sawdust with 1% NaOH solution at 121 degrees C dissolved 19.7% of the dry matter, mainly hemicellulose and lignin. Fermentation of the treated solids by Chaetomium cellulolyticum for 48 h gave a product containing 12.5% crude protein (total N x 6.25) on a dry weight basis. The in vitro rumen digestibility of the 48-h fermentation product was 30%, compared to 24% for the alkali-treated but unfermented sawdust. Growth was independent of sawdust particle size in the range 40 to 100 mesh. Fermentation of the pretreatment liquor gave a product containing up to 50% crude protein (dry weight basis) with an in vitro rumen digestibility of 65 to 76%. Approximately 6.7 g of crude protein was obtained from the treated solids and 2.2 g from the pretreatment liquor per 100 g of sawdust treated. The product from the pretreatment liquor fermentation has potential as a high-protein animal feed supplement but could not be produced economically without an outlet for the relatively indigestible product from the solids fermentation. Growth on the pretreatment liquor was strongly pH dependent; there was a considerable increase in the lag phase when the pH was lowered from 7.5 to 5.2. This effect appears to be due to an inhibitor whose toxicity is reduced at high pH.

9.
Proc Natl Acad Sci U S A ; 97(19): 10509-13, 2000 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-10973484

RESUMO

Mast cells (MC) are stem cell factor-dependent tissue-based hematopoietic cells with substantial functional heterogeneity. Cord blood-derived human MC (hMC) express functional receptors for IL-5, and IL-5 mediates stem cell factor-dependent comitogenesis of hMC in vitro. Although IL-5 is not required for normal hMC development, we considered that it might prime hMC for their high-affinity Fc receptor for IgE (FcvarepsilonRI)-dependent generation of cytokines, as previously demonstrated for IL-4. Compared with hMC maintained in stem cell factor alone, hMC primed with IL-5 expressed 2- to 4-fold higher steady-state levels of TNF-alpha, IL-5, IL-13, macrophage inflammatory protein 1alpha, and granulocyte-macrophage colony-stimulating factor transcripts 2 h after FcvarepsilonRI crosslinking and secreted 2- to 5-fold greater quantities of the corresponding cytokines, except IL-13, at 6 h. Unlike IL-4, IL-5 priming did not enhance FcvarepsilonRI-dependent histamine release. Thus, IL-5 augments cytokine production by hMC by a mechanism distinct from that of IL-4 and with a different resultant profile of cytokine production. These observations suggest a potentially autocrine effect of IL-5 on hMC for amplification of allergic immune responses, in addition to its recognized paracrine effects on eosinophils, and implicate both IL-4 and IL-5 in the modulation of the hMC phenotype.


Assuntos
Citocinas/biossíntese , Imunoglobulina E/fisiologia , Interleucina-4/fisiologia , Interleucina-5/fisiologia , Mastócitos/imunologia , Humanos , Hipersensibilidade/imunologia
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