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1.
Int Immunopharmacol ; 93: 107341, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33486334

RESUMEN

Although acute stress generally exerts positive effects on the immune system, chronic stress typically causes immunosuppression via the hypothalamic-pituitary-adrenal (HPA) axis. In this study, the effects of capsaicin (1.28 mg/kg intraperitoneally [i.p.] for 7 days) on immune parameters were evaluated under conditions of chronic stress. Capsaicin treatment significantly increased the immune response as evaluated by the delayed-type hypersensitivity (DTH) reaction to dinitrofluorobenzene (DNFB) and splenocyte proliferation assays- It also is able to rescue the splenocytes of the apoptosis induced by stress. The capsaicin treatment increased the production of Th1 cytokines and decreased the production of Th2 cytokines and TGF-ß1 in the plasma and culture supernatants of immunosuppressed mice, which is associated with the modulation of Th2 induced by stress cells. Moreover, the production of corticosterone significantly decreased in capsaicin-treated animals as compared to control groups. The capsaicin treatment further attenuated the immunosuppression induced by the corticosterone treatment (40 mg/kg i.p. for 7 days), albeit less potently, as exhibited in the DTH response. Intriguingly, the capsaicin treatment decreased the induction of IL-10, IL-4, and TGF-ß1 through high doses of corticosterone, indicating direct cellular immunomodulation. These results show, that capsaicin is able to modulate chronic stress-induced immunosuppression, mediating corticosterone released inhibition, but also, that capsaicin significantly modulates the pharmacological action of corticosterone in vivo.


Asunto(s)
Capsaicina/farmacología , Tolerancia Inmunológica/efectos de los fármacos , Factores Inmunológicos/farmacología , Estrés Fisiológico/efectos de los fármacos , Animales , Proliferación Celular/efectos de los fármacos , Corticosterona/farmacología , Citocinas/sangre , Citocinas/inmunología , Dinitrofluorobenceno , Hipersensibilidad Tardía/inmunología , Masculino , Ratones Endogámicos BALB C , Bazo/citología , Estrés Fisiológico/inmunología , Factor de Crecimiento Transformador beta1/sangre , Factor de Crecimiento Transformador beta1/inmunología
2.
Int J Mol Sci ; 19(12)2018 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-30545135

RESUMEN

Inflammatory bowel disease is triggered by an uncontrolled immune response associated with genetic, environmental, and intestinal microbiota imbalance. Ipomoea asarifolia (IA), popularly known as "salsa" or "brave salsa", belongs to the Convolvulaceae family. The aim of this approach was to study the preventive effect of IA aqueous extract in 2,4-dinitrobenzene sulfonic acid (DNBS)-induced colitis in rats. Rats pretreated with IA extract or sulfasalazine (SSZ) received intracolonic instillation of DNBS in 50% ethanol (v/v). IA extract presented a protective effect against intestinal inflammation, with improvement in the disease activity index and macroscopic damage. IA or SSZ significantly reduced myeloperoxidase activity, and also down-regulation of the gene expression of JNK1, NF-κß-p65, STAT3, and decreased levels of TNFα, IL-1ß, and increased IL-10, associated with a significant improvement of oxidative stress, in addition to a reduction in MDA and an increase of glutathione in colonic tissue. The protective effect of the extract was also confirmed in histological evaluation, showing preservation of the colonic cytoarchitecture. Immunohistochemical analysis revealed down-regulation of NF-κß-p65, iNOS, IL-17, and up-regulation of SOCs-1 and MUC-2. IA extract presents antioxidant and anti-inflammatory intestinal properties, and proved to be a potential application for preventing damage induced by DNBS.


Asunto(s)
Antiinflamatorios/uso terapéutico , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , Intestinos/patología , Ipomoea/química , Extractos Vegetales/uso terapéutico , Animales , Antiinflamatorios/farmacología , Colitis/patología , Citocinas/metabolismo , Dinitrofluorobenceno/análogos & derivados , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Proteína Quinasa 8 Activada por Mitógenos/genética , Proteína Quinasa 8 Activada por Mitógenos/metabolismo , FN-kappa B/genética , FN-kappa B/metabolismo , Tamaño de los Órganos , Estrés Oxidativo/efectos de los fármacos , Peroxidasa/metabolismo , Extractos Vegetales/farmacología , Ratas Wistar , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/metabolismo
3.
PLoS One ; 12(9): e0185382, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28957373

RESUMEN

This study evaluated the intestinal anti-inflammatory effects of goat whey in a mouse model of colitis induced by 2,4-dinitrobenzenesulfonic acid that resembles human IBD. At a concentration of 4 g/kg/day, the goat whey improved the symptoms of intestinal inflammation, namely by decreasing the disease activity index, colonic weight/length, and leukocyte infiltration. Moreover, goat whey inhibited NF-κB p65 and p38 MAPK signaling pathways and consequently down-regulated the gene expression of various proinflammatory markers such as IL-1ß, IL-6, IL-17, TNF-α, iNOS, MMP-9, ICAM-1. Also, goat whey increased the expression of proteins such as mucins, occludin proteins and cytokine signalling suppressors. The immunomodulatory properties of goat whey were also evaluated in vitro using the murine macrophage cell line Raw 264 and CMT-93 cells derived from mouse rectum carcinomas. The results revealed the ability of goat whey to inhibit the production of NO and reduce IL-6 production in LPS-stimulated cells. In conclusion, goat whey exhibited anti-inflammatory effects in the DNBS model of intestinal inflammation, and these observations were confirmed by its immunomodulatory properties in vitro. Together, our results indicate that goat whey could have applications for the treatment of IBD.


Asunto(s)
Antiinflamatorios/uso terapéutico , Colitis/inducido químicamente , Colitis/patología , Intestinos/patología , Suero Lácteo/química , Animales , Antiinflamatorios/farmacología , Colitis/genética , Citocinas/genética , Citocinas/metabolismo , Dinitrofluorobenceno/análogos & derivados , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática , Técnica del Anticuerpo Fluorescente , Regulación de la Expresión Génica/efectos de los fármacos , Cabras , Mediadores de Inflamación/metabolismo , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/patología , Intestinos/efectos de los fármacos , Masculino , Ratones , Células RAW 264.7 , Reacción en Cadena en Tiempo Real de la Polimerasa
4.
Appl Microbiol Biotechnol ; 100(1): 385-396, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26476654

RESUMEN

Probiotics are live microorganisms which when administered in adequate amounts, confer health benefits on the host. Their use is more and more widespread for both prevention and treatment of diseases, including traveler's diarrhea and inflammatory bowel diseases (IBDs). In this work, we isolated and characterized novel candidate probiotic strains from pulque (xaxtle), a traditional Mexican alcoholic fermented beverage. A total of 14 strains were obtained from xaxtle samples isolated from three different Mexican regions. Species identification was performed by biochemical methods and 16S rRNA gene targeted PCR. The isolates belonged to the Lactobacillus plantarum, Lactobacillus paracasei, Lactobacillus brevis, and Lactobacillus composti phylogenetic groups, with L. brevis being the most dominant group. Bacteria were tested for lysozyme, low pH, and bile acid resistance. Moreover, the strains were tested for adherence to human intestinal epithelial cells and screened for their immunomodulatory properties using a cellular model. Selected bacterial strains with anti-inflammatory properties were then tested in vivo in a dinitro-benzene sulfonic acid (DNBS)-induced chronic colitis mouse model, and weight loss, gut permeability, and cytokine profiles were measured as readouts of inflammation. One of the selected strains, Lactobacillus sanfranciscensis LBH1068, improved mice health as observed by a reduction of weight loss, significant decreases in gut permeability, and cytokine modulation. Altogether, our results highlighted the potential of lactobacilli isolated from pulque and in particular the strain L. sanfranciscensis LBH1068 as a novel probiotic to treat IBD.


Asunto(s)
Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Bebidas/microbiología , Lactobacillus/clasificación , Lactobacillus/aislamiento & purificación , Probióticos/farmacología , Probióticos/uso terapéutico , Animales , Antiinflamatorios/aislamiento & purificación , Adhesión Bacteriana , Línea Celular , Análisis por Conglomerados , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , Colitis/patología , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Dinitrofluorobenceno/análogos & derivados , Dinitrofluorobenceno/toxicidad , Modelos Animales de Enfermedad , Células Epiteliales/microbiología , Humanos , Lactobacillus/fisiología , México , Ratones , Datos de Secuencia Molecular , Filogenia , Probióticos/aislamiento & purificación , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Resultado del Tratamiento
5.
Org Biomol Chem ; 11(14): 2302-9, 2013 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-23423183

RESUMEN

We herein report results obtained from an integrated experimental and theoretical study on aromatic nucleophilic substitution (S(N)Ar) reactions of a series of amines towards 1-fluoro-2,4-dinitrobenzene in water. Specific nucleophile-electrophile interactions in the title reactions have been kinetically evaluated. The whole series undergoes S(N)Ar reactions where the formation of the Meisenheimer complex is rate determining. Theoretical studies concerning specific interactions are discussed in detail. It is found that H-bonding effects along the intrinsic reaction coordinate profile promote the activation of both the electrophile and the nucleophile. Using these results, it is possible to establish a hierarchy of reactivity that is in agreement with the experimental data. Second order energy perturbation energy analysis highlights the strong interaction between the ortho-nitro group and the acidic hydrogen atom of the amine. The present study strongly suggests that any theoretical analysis must be performed at the activated transition state structure, because the static model developed around the reactant states hides most of the relevant specific interactions that characterize the aromatic substitution process.


Asunto(s)
Aminas/química , Dinitrofluorobenceno/química , Modelos Moleculares , Agua/química , Hidrazinas/química , Cinética
6.
Int Immunopharmacol ; 6(5): 774-81, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16546708

RESUMEN

Hypothalamic-pituitary-adrenal (HPA) axis activation-induced immunosuppression is associated with increased concentration of circulating corticosterone and impaired cellular immune responses. The purpose of this study was to investigate the effect of chronic HPA axis activation on the cellular immune response, Th1/Th2 cytokine profile, and concentration of corticosterone. Mice were divided into two groups: a control group comprised of healthy, untreated mice that received no stress, and an HPA axis-activated group that received stress through electric shock (ES). The delayed-type hypersensitivity reaction to dinitrofluorobenzene, splenocyte proliferative response to mitogens Concanavalin A and lipopolysaccharide, Th1 and Th2 profile, and TGF-beta1 production were measured in plasma and in culture supernatants. The corticosterone concentration was also measured in plasma. In the ES group, elevated plasma corticosterone concentration was associated with immunosuppression and a significant decrease in plasma concentrations of IL-2, IL-4, and TGF-beta1. In vitro IL-2 production in response to Con A was significantly lower in the ES group than in the control group. TGF-beta1 production in nonstimulated and stimulated cultures in response to either mitogen was significantly lower in the ES group than in the control group. Plasma concentrations of IFN-gamma and IL-10 did not differ significantly between groups. The concentrations of IFN-gamma, IL-4, and IL-10 in the supernatants of splenocytes stimulated with either mitogen and IL-4 production by nonstimulated cells were significantly higher in the ES group than in the control group. These results suggest that corticosterone mediates the immunosuppression induced by HPA axis activation, and induces dysregulation of the Th1/Th2 cytokine profile.


Asunto(s)
Citocinas/sangre , Sistema Hipotálamo-Hipofisario/inmunología , Sistema Hipófiso-Suprarrenal/inmunología , Células TH1/inmunología , Células Th2/inmunología , Animales , Proliferación Celular/efectos de los fármacos , Concanavalina A/farmacología , Corticosterona/sangre , Citocinas/inmunología , Dinitrofluorobenceno/toxicidad , Hipersensibilidad Tardía/inducido químicamente , Tolerancia Inmunológica , Lipopolisacáridos/farmacología , Masculino , Ratones , Ratones Endogámicos BALB C , Mitógenos/farmacología , Bazo/citología , Bazo/efectos de los fármacos , Bazo/inmunología
7.
Int Immunopharmacol ; 3(1): 75-80, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12538036

RESUMEN

We evaluated the effects of Ginkgo biloba extract (EGb 761) on the cellular immune response of rats with immunosuppression induced by activation of the hypothalamic-pituitary-adrenal (HPA) axis. Groups of five rats were subjected to chronic stress by the application of daily electric shocks (ES) over 7 days. This stress produced a significant decrement in the delayed-type hypersensitivity response (DTH) to dinitrofluorobenzene (DNFB), and a decrease in the proliferation index of splenocytes. Treatment with oral doses of the phytopharmaceutical EGb 761 (100 mg/kg per day over 7 days) restored both the DTH response to DNFB and the proliferation index. EGb 761 has stress-alleviating properties through its moderation of corticosterone levels. It also possesses antioxidant activity that may contribute to its effects on the immune response. Our observations indicate that the phytopharmaceutical EGb 761 possesses immunostimulatory properties.


Asunto(s)
Ginkgo biloba/química , Sistema Hipotálamo-Hipofisario/fisiología , Inmunidad/efectos de los fármacos , Sistema Hipófiso-Suprarrenal/fisiología , Extractos Vegetales/farmacología , Animales , Corticosterona/sangre , Dinitrofluorobenceno/farmacología , Hipersensibilidad Tardía/inmunología , Terapia de Inmunosupresión , Ratas , Estrés Fisiológico
8.
Phytother Res ; 16(3): 253-5, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12164271

RESUMEN

The phagocytic activity and delayed-type Hypersensitivity (DTH) response to dinitrofluorobenzene (DNFB) of healthy BALB/c mice treated orally (100 mg/kg/day for 7 days) using two Ginkgo biloba extracts were studied. The phytopharmaceuticals Gb 30 (Alban Muller International, France) and EGb 761 (Schwabe, Germany) administered orally stimulated the phagocytic activity of peritoneal and alveolar macrophages. Likewise, the DTH response was found to be increased only with Gb 30 treatment. These results suggest that Ginkgo biloba possesses immunological activity in addition to the biological activity reported. The different chemical concentration of the components of the Ginkgo biloba extracts mentioned above may be responsible for the differences in the observed findings.


Asunto(s)
Ginkgo biloba , Hipersensibilidad Tardía/tratamiento farmacológico , Fagocitosis/efectos de los fármacos , Fitoterapia , Extractos Vegetales/farmacología , Animales , Dinitrofluorobenceno/farmacología , Hipersensibilidad Tardía/inducido químicamente , Macrófagos Alveolares/efectos de los fármacos , Macrófagos Alveolares/fisiología , Macrófagos Peritoneales/efectos de los fármacos , Macrófagos Peritoneales/fisiología , Masculino , Ratones , Ratones Endogámicos BALB C , Extractos Vegetales/uso terapéutico
9.
Toxicon ; 35(4): 607-12, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9133715

RESUMEN

The effect of venom of South American rattlesnake Crotalus durissus terrificus (cdt) on the humoral and cellular immune response was studied in BALB/c mice that were immunized with soluble antigens [human serum albumin (HSA) or chicken ovoalbumin (OVA)] or sensitized to DNFB 1 hr after venom injection. Pretreatment of the animals with cdt venom induced a significant reduction in the level of anti-OVA and anti-HSA IgG antibodies. The effect of crotoxin, a major neurotoxic component of cdt venom, its acidic non-toxic subunit (CA) and its basic phospholipase A2 subunit (CB) was also studied. The whole crotoxin molecule was as able as cdt venom to induce a significant decrease in the level of anti-OVA and anti-HSA IgG antibodies. However, the CA and CB subunits of crotoxin did not change the antibody level to either antigen, suggesting that the suppressive effect of crotoxin requires the intact molecule. Both cdt venom and the whole crotoxin molecule were able to induce a significant decrease in the level of anti-HSA IgG1 antibodies. The levels of other IgG isotypes and IgE were barely detectable and could not be estimated. In spite of their suppressive effect on the humoral immune response neither cdt venom nor crotoxin had any effect on the cellular immune response as estimated by contact sensitivity reaction to DNFB. It is suggested that cdt venom and its crotoxin component have an inhibitory effect on the humoral but not on the cellular immune response.


Asunto(s)
Formación de Anticuerpos/efectos de los fármacos , Venenos de Crotálidos/toxicidad , Inmunidad Celular/efectos de los fármacos , Mordeduras de Serpientes/inmunología , Animales , Anticuerpos/sangre , Anticuerpos/inmunología , Formación de Anticuerpos/inmunología , Antígenos/inmunología , Dinitrofluorobenceno/inmunología , Inmunidad Celular/inmunología , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Ratones , Ratones Endogámicos BALB C , Ovalbúmina/inmunología , Albúmina Sérica/inmunología
10.
J Parasitol ; 82(3): 454-7, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8636852

RESUMEN

The influence of nonspecific and immunologically elicited inflammatory responses on the development of metastatic lesions was examined in the hamster model of Leishmania (Viannia) panamensis infection. Delayed type hypersensitivity (DTH) responses were induced using the contact sensitizing agent DNFB (2, 4-dinitro-1-fluorobenzene) and infection with L. panamensis followed by intradermal application of leishmanin. Nonspecific inflammatory response was achieved by the surgical excision of toes. The inductive and eliciting procedures were performed on the ears and fore and hind paws of the right side of experimental groups of hamsters that were inoculated in the snout with a highly metastatic strain of L. panamensis (MHOM/COL/84/1099). Skin metastases were detected by physical evaluation at 15-day intervals over a period of 7-8 mo. Suspected metastases were parasitologically confirmed by culture of tissue fluid aspirated from the lesion. The frequency of metastatic lesions was greater in hamsters subjected to inflammatory stimuli (14/38) than control animals (6/33; P = 0.035). Likewise, the frequency of metastases at the site of induction and elicitation of inflammation (18/22 lesions) in the experimental groups was greater than that observed at the same site in control animals (5/11 lesions; P = 0.017). These findings support a causal relationship between inflammatory response and the development of lesions in this model of secondary disease caused by L. panamensis.


Asunto(s)
Leishmania guyanensis/fisiología , Leishmaniasis Mucocutánea/patología , Piel/patología , Animales , Antígenos de Protozoos/inmunología , Cricetinae , Dinitrofluorobenceno , Modelos Animales de Enfermedad , Femenino , Hipersensibilidad Tardía , Inflamación , Pruebas Intradérmicas , Leishmania guyanensis/inmunología , Leishmaniasis Mucocutánea/inmunología , Masculino , Mesocricetus , Piel/inmunología , Piel/lesiones , Heridas y Lesiones/complicaciones
11.
Int Arch Allergy Immunol ; 106(2): 166-8, 1995 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7819746

RESUMEN

Interleukin-12 (IL-12) is a heterodimeric cytokine that has pleiotropic effects on the immune response. We have studied the effect of recombinant IL-12 on allergic contact dermatitis in the mouse. IL-12 substantially up-regulates the induction of sensitivity to the contact allergens dinitrofluorobenzene and oxazolone.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Dermatitis Alérgica por Contacto/etiología , Interleucina-12/farmacología , Animales , Dinitrofluorobenceno/inmunología , Femenino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Proteínas Recombinantes/farmacología
12.
Int Arch Allergy Appl Immunol ; 88(3): 345-7, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2498213

RESUMEN

Using the model of allergic contact dermatitis in mice, we have demonstrated that local administration of recombinant (r) murine gamma interferon (gamma-rIFN) to the sensitization site substantially enhances the acquisition of delayed-type hypersensitivity. Single doses of gamma-rIFN from 500 to 2,000 U immunopotentiate successfully, with a suggestion of a better response at the higher doses. The immunoadjuvant effect is lost when the injections of gamma-rIFN are at a site distant from the sensitization site. Kinetic studies imply that gamma-rIFN is most effective when given at the time of sensitization, but significant immunopotentiation can be seen when gamma-rIFN is given several days before or after sensitization.


Asunto(s)
Adyuvantes Inmunológicos/administración & dosificación , Dermatitis por Contacto/etiología , Interferón gamma/administración & dosificación , Animales , Dermatitis por Contacto/inmunología , Dinitrofluorobenceno/administración & dosificación , Femenino , Inmunización , Inyecciones Intradérmicas , Ratones , Ratones Endogámicos BALB C , Oxazolona/administración & dosificación , Proteínas Recombinantes
13.
Acta bioquím. clín. latinoam ; 22(3): 391-401, sept. 1988. ilus, Tab
Artículo en Español | BINACIS | ID: bin-29473

RESUMEN

Los grupos amino de la XOD (Xantina oxidasa) del hígado de rata son inhibidos por reactivos como el benzaldehído y el 2,4-dinitrofluorbenceno. Esta inhibición ocurre más rápidamente a elevados pH y es progresiva e irreveersible. Estos reactivos atacan grupos amino de la XOD, pero no se excluye que haya otros grupos que puedan ser bloqueados. Si se representa la inhibición en función de la unión con el benaldehído o 2,4-dinitrofluorbenceno, se observa que una fracción relativamente pequeña del total de grupos amino de la XOD es más reactiva a esta inhibició y que estos grupos amino se modifican por estos inhibidores. Los estudios de unión del benzaldehído sugieren dos clases de actividad enzimática, presentes en igual proporción, pero difieren en su sensibilidad frente al benzaldehído. Los parámetros cinéticos de la actividad residual de la XOD tratada con benzaldehído se asemejan a los de la enzima nativa, excepto el comprotamiento inhibitorio frente a altas concentraciones de sustrato (AU)


Asunto(s)
Técnicas In Vitro , Xantina Oxidasa/antagonistas & inhibidores , Inhibidores Enzimáticos , Dinitrofluorobenceno/antagonistas & inhibidores , Benzaldehídos/antagonistas & inhibidores , Hígado/enzimología
14.
Acta bioquím. clín. latinoam ; Acta bioquím. clín. latinoam;22(3): 391-401, sept. 1988. ilus, tab
Artículo en Español | LILACS | ID: lil-68939

RESUMEN

Los grupos amino de la XOD (Xantina oxidasa) del hígado de rata son inhibidos por reactivos como el benzaldehído y el 2,4-dinitrofluorbenceno. Esta inhibición ocurre más rápidamente a elevados pH y es progresiva e irreveersible. Estos reactivos atacan grupos amino de la XOD, pero no se excluye que haya otros grupos que puedan ser bloqueados. Si se representa la inhibición en función de la unión con el benaldehído o 2,4-dinitrofluorbenceno, se observa que una fracción relativamente pequeña del total de grupos amino de la XOD es más reactiva a esta inhibició y que estos grupos amino se modifican por estos inhibidores. Los estudios de unión del benzaldehído sugieren dos clases de actividad enzimática, presentes en igual proporción, pero difieren en su sensibilidad frente al benzaldehído. Los parámetros cinéticos de la actividad residual de la XOD tratada con benzaldehído se asemejan a los de la enzima nativa, excepto el comprotamiento inhibitorio frente a altas concentraciones de sustrato


Asunto(s)
Benzaldehídos/antagonistas & inhibidores , Dinitrofluorobenceno/antagonistas & inhibidores , Inhibidores Enzimáticos , Hígado/enzimología , Técnicas In Vitro , Xantina Oxidasa/antagonistas & inhibidores
15.
Int J Pept Protein Res ; 30(3): 423-30, 1987 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3692688

RESUMEN

Derivatives of bovine growth hormone, containing monoaminotyrosyl residues in positions 35, 42 and 174, were treated at pH 3.6 with a bifunctional reagent, 1,5-difluoro-2,4-dinitrobenzene. Under these conditions aminotyrosyl groups reacted. On changing the pH to 9.3, the second fluorine atom of the reagent was substituted with the sterically adjacent side groups of lysine, since the excess of reagent had been previously removed. The modified protein underwent cyanogen bromide treatment. Peptides containing the crosslinks were purified from tryptic digests of the cyanogen bromide fragments by HPLC. Results show that aminoTyr 174 was able to form dinitrophenylene bridges with Lys 111, Lys 29 and Lys 170. AminoTry 35 was found crosslinked to Lys 29. Taking into account the size of the reagent, it may be inferred that Lys 29, 111 and 170 are located at approximately 5 A from Tyr 174 in the bovine growth hormone molecule.


Asunto(s)
Dinitrofluorobenceno , Hormona del Crecimiento/análisis , Nitrobencenos , Secuencia de Aminoácidos , Animales , Bovinos , Cromatografía Líquida de Alta Presión , Dinitrofluorobenceno/análogos & derivados , Concentración de Iones de Hidrógeno , Datos de Secuencia Molecular
16.
Rev. patol. trop ; 15(1): 35-82, jan.-abr. 1986.
Artículo en Portugués | LILACS | ID: lil-162763

RESUMEN

Estudou-se a resposta imune da leishmaniose visceral em hamsteres inoculados com (10) x (7) amastigotas da Leishmania sp. cepa 70 por via intraperitonial. As alteraçöes imunológicas encontradas foram: produçåo de anticorpos anti-leishmânia, aumento da densidade linfocitária na zona B-dependente e reaçåo de hipersensibilidade tardia específica negativa. A modulaçåo da resposta imune com o uso da ciclofosfamida mostrou uma diminuiçåo no nível de anticorpos anti-leishmânia, depleçåo linfocitária da zona B-dependente, aparecimento da reaçåo de leishmania e sugeriu a existência de célula reguladora da reaçåo de hipersensibilidade tardia, sensível à ciclofosfamida, em hamster


Asunto(s)
Animales , Ratones , Leishmania donovani/fisiología , Cricetinae/parasitología , Ciclofosfamida , Leishmaniasis Visceral/inmunología , Formación de Anticuerpos , Interacciones Huésped-Parásitos , Linfocitos B , Linfocitos T , Oxazolona , Dinitrofluorobenceno , Hematoxilina , Hipergammaglobulinemia , Bazo , Ratones Endogámicos BALB C , Hígado , Macrófagos , Neutrófilos
20.
s.l; s.n; jun. 1976. 10 p. tab, graf.
No convencional en Inglés | Sec. Est. Saúde SP, HANSEN, Hanseníase, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1240553

RESUMEN

Immunologic responses were measured in 46 patients with lepromatous leprosy. These patients were not distinguishable from controls on the basis of responses to soluble intradermal antigens, sensitization to contactants, peripheral blood T- and B-cell percentages, in vitro lymphocyte responses to a mitogen, or the prevalence of autoantibodies. Generalized immunologic abnormalities in patients with lepromatous leprosy are neither predisposing causes nor necessary accompaniments of lepromatous leprosy, but are probably remote sequellae of the illness. By implication, the generalized immunologic abnormalities reported in other diseases are likely to be remote sequellae of the particular illness.


Asunto(s)
Masculino , Femenino , Humanos , Adulto , Persona de Mediana Edad , Anciano , Lepromina/farmacología , Dermatitis Atópica/inducido químicamente , Dermatitis por Contacto/etiología , Lepra/clasificación , Lepra/genética , Lepra/inmunología , Lectinas/farmacología , Linfocitos T/inmunología , Piel/inmunología , Antígenos , Activación de Linfocitos , Autoanticuerpos , Recuento de Leucocitos , Dinitroclorobenceno , Dinitrofluorobenceno , Linfocitos B/inmunología
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