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1.
Biotech Histochem ; 93(3): 220-229, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29393700

RESUMO

We used ethylenediaminetetraacetic acid dianhydride (EDTAD) to modify oxalate decarboxylase (OXDC) to improve its adsorption on calcium oxalate stones. The modified sites were identified by Ultra performance liquid chromatography-mass spectrometry (UPLC-MS) and the adsorption mechanism of the EDTAD-modified OXDC on calcium oxalate (CaOx) was investigated. We investigated adsorption time, initial enzyme concentration, temperature and solution pH on the adsorption process. Data were analyzed using kinetics, thermodynamics and isotherm adsorption models. UPLC-MS showed that EDTAD was attached to OXDC covalently and suggested that the chemical modification occurred at both the free amino of the side chain and the α-NH2 of the peptide. The adsorption capacity of the EDTAD-OXDC on calcium oxalate was 53.37% greater than that of OXDC at the initial enzyme concentration of 5 mg/ml, pH = 7.0, at 37° C. The modified enzyme (EDTAD-OXDC) demonstrated improved oxalate degradation activity at pH 4.5-6.0. Kinetic data fitting analysis suggested a pseudo second order kinetic model. Estimates of the thermodynamic parameters including ΔG0, ΔH0 and ΔS0 of the adsorption process showed it to be feasible, spontaneous and endothermic. Isotherm data fitting analysis indicated that the adsorption process is reduced to monolayer adsorption at a low enzyme concentration and to multilayer adsorption at a high enzyme concentration. It may be possible to apply OXDC to degradation of calcium oxalate stones.


Assuntos
Oxalato de Cálcio/química , Carboxiliases/química , Compostos de Amônio Quaternário/química , Adsorção
2.
Zhonghua Yi Xue Za Zhi ; 97(5): 325-331, 2017 Feb 07.
Artigo em Chinês | MEDLINE | ID: mdl-28219187

RESUMO

Objective: To investigate the feasibility of utilizing the current acute gastrointestinal injury(AGI) grading system, and explore the association of severity of AGI grade with clinical outcome in critically ill patients. Methods: The adult patients from 14 general ICUs in Zhejiang Province with an expected admission to ICU for at least 24 h were recruited, and all clinical, laboratory, and survival data were prospectively collected. The AGI grade was daily assessed based on GIsymptoms, feeding details and organ dysfunctionon the first week of admission to ICU.The intra-abdominal pressures(IAP) was measured using AbViser device. Results: Of 550 patients enrolled, mean values for age and APACHE Ⅱ score were (64.9±17.2) years and (19.5±7.4), respectively. 456 patients(82.9%) took mechanical ventilation, and 470 patients were identified for AGI. The distribution of AGI grade on the frist day of ICU admission were 50.6%(Ⅰ grade, n=238), 34.2%(Ⅱ grade, n=161), 12.4%(Ⅲ grade, n=58) and 2.8%(Ⅳ, n=13), respectively, while the distribution of the global AGI grade based on the 7-day AGI assessment of ICU admission were 24.5%(Ⅰ grade, n=115), 49.4%(Ⅱ grade, n=232), 20.6%(Ⅲ grade, n=97) and 5.5%(Ⅳ, n=26), respectively. 28- and 60-day mortality rate was 29.3%(n=161) and 32.5%(n=179), respectively. The patients with AGI had a higher 28-(31.1% vs 18.8%, P=0.025) and 60-day survival rate(34.7% vs 20.0%, P=0.01) than those with non-AGI, and also there were positive correlations between AGI grade and 28- and 60-day mortality(P<0.001). Univariate Cox regression analysis showed that age, the source of medicial admission, diabetes mellitus, coronary heart disease, the use of vasoactive drugs, serum creatinine and lactate, mechanical ventilation, APACHE Ⅱ score, the AGI grade in the first day of ICU admission and feeding intolerance within the first week of ICU stay were significantly(P≤0.02) associated with mortality. In multivariate analysis including all these variables, the source of medical admission(χ(2)=4.34, P=0.04), diabete mellitus(χ(2)=3.96, P=0.05), the use of vasoactive drugs(χ(2)=6.55, P=0.01), serum lactate(χ(2)=4.73, P=0.03), the global AGI grade in the 7-day of ICU admission(χ(2)=7.10, P=0.008), and APACHE Ⅱ score(χ(2)=12.1, P<0.001) remained independent predictors for 60-day mortality.In the further subgroup analysis including 402 patients with 7-day survival, the feeding intolerance within the first week of ICU stay could provide independent and incremental prognostic value of 60-day mortality wtih increased χ(2)value of Cox regression model(χ(2)=52.2 vs 41.9, P=0.007) . Conclusion: The AGI grading system is useful for identifying the severity of gastrointestinal dysfunction, and could be used as a strong predictor of impaired outcome. The results provide evidence to support that feeding intolerance within 7 days of admission to ICU was an independent determinant of mortality.


Assuntos
Estado Terminal , Unidades de Terapia Intensiva , Adulto , Idoso , Gastroenteropatias , Humanos , Ácido Láctico , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Estudos Prospectivos , Respiração Artificial , Taxa de Sobrevida
3.
Clin Exp Allergy ; 33(11): 1595-602, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14616874

RESUMO

BACKGROUND: Food allergy is a common disease without effective treatment. Since strict elimination of food allergens may be difficult, strategies for effective intervention are urgently needed. OBJECTIVE: The aim was to investigate the prophylactic use of orally administrated FIP-fve, an immunomodulatory protein isolated from the edible mushroom Flammulina velutipes, in a murine model of food allergy. METHODS: BALB/c mice were immunized twice intraperitoneally with ovalbumin (OVA), at an interval of 2 weeks. Before and during each period of immunization, FIP-fve (200 microg per mouse) or phosphate-buffered saline was given orally every other day with a total of five doses. Then OVA-specific antibodies and cytokine profiles were determined. Subsequently, the mice were orally challenged with OVA. Symptoms of anaphylaxis, levels of plasma histamine, and histology of intestines were examined. RESULTS: Mice receiving oral FIP-fve treatment during sensitization to OVA had an impaired OVA-specific IgE response with a Th1-predominant cytokine profile. These mice were protected from systemic anaphylaxis-like symptoms induced by subsequent oral challenge with OVA. CONCLUSION: Oral administration of FIP-fve has a Th1-skewing effect on the development of the allergen-specific immune response, and may serve the purpose of immunoprophylaxis for food allergy and other allergic diseases.


Assuntos
Anafilaxia/prevenção & controle , Hipersensibilidade Alimentar/prevenção & controle , Proteínas Fúngicas/uso terapêutico , Lectinas/uso terapêutico , Administração Oral , Anafilaxia/imunologia , Anafilaxia/patologia , Animais , Células Apresentadoras de Antígenos/imunologia , Divisão Celular/imunologia , Feminino , Hipersensibilidade Alimentar/imunologia , Hipersensibilidade Alimentar/patologia , Proteínas Fúngicas/imunologia , Histamina/sangue , Imunoglobulina E/biossíntese , Interferon gama/biossíntese , Interleucina-4/biossíntese , Jejuno/patologia , Lectinas/imunologia , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina , Células Th1/imunologia
4.
Clin Exp Allergy ; 33(8): 1067-75, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12911780

RESUMO

BACKGROUND: The aetiology of food allergy remains unclear. Although failure to develop or breakdown in oral tolerance has been proposed, the existence of physiologic sensitization routes other than the gastrointestinal tract cannot be excluded. OBJECTIVE: The purpose of this study is to clarify whether or not exposure to allergen through the skin can promote food allergy. METHODS: BALB/c mice were shaved on the back, and a patch impregnated with 100 micro g of ovalbumin (OVA) was applied to the dorsal skin for a 1-week period and then removed. After three courses of sensitization, OVA-specific antibodies in sera were measured, and then mice were orally challenged with 50 mg of OVA. Anaphylactic symptoms, plasma histamine levels, and histology of intestines and lungs after oral challenge were examined. RESULTS: Epicutaneous (EC) sensitization of mice to OVA induced a high level of OVA-specific IgE. Subsequent oral challenge with OVA resulted in symptoms of systemic anaphylaxis with elevated levels of plasma histamine as well as histological changes in both intestines and lungs. In the presence of anti-IL-4 antibodies, EC sensitization failed to provoke an IgE response, but still induced a Th2-predominant cellular immune response in lungs after oral challenge. CONCLUSION: We demonstrated for the first time that food allergy can be induced by allergen exposure through the skin. Our results identify a novel role of EC sensitization in the pathogenesis of food allergy.


Assuntos
Alérgenos/administração & dosagem , Hipersensibilidade Alimentar/etiologia , Administração Cutânea , Administração Oral , Alérgenos/imunologia , Anafilaxia/etiologia , Anafilaxia/imunologia , Anafilaxia/patologia , Animais , Feminino , Hipersensibilidade Alimentar/imunologia , Hipersensibilidade Alimentar/patologia , Histamina/sangue , Imunoglobulina E/biossíntese , Interleucina-4/imunologia , Intestinos/patologia , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/administração & dosagem , Ovalbumina/imunologia , Células Th2/imunologia
6.
Br J Haematol ; 115(2): 435-41, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11703347

RESUMO

Cord blood T cells are much more likely to be induced to apoptosis in vitro than adult T cells. Nevertheless, the expression of Fas is markedly lower on cord blood lymphocytes than on peripheral blood lymphocytes. In the current investigation, we determined the capacity of tumour necrosis factor-alpha (TNF-alpha) to induce apoptosis in human naïve T cells in cord blood, and assessed the roles of two distinct TNF receptors (TNFRs) in mediating death signals. After activation, cord blood T cells were sensitive to TNF-alpha-induced apoptosis, and interleukin 2 (IL-2) could prevent this apoptotic response. Both TNFR1 (p55) and TNFR2 (p75) expressed on activated cord blood T cells were able to transmit apoptotic signals. Moreover, a synergistic effect was observed by a combination of TNFR1- and TNFR2-signals. Additionally, CD4(+) T cells showed higher sensitivity to TNFR-mediated apoptosis than CD8(+) T cells. These data suggest that TNF-alpha probably is a mediator of apoptosis in cord blood T cells in vivo and may contribute to the low incidence of graft-versus-host disease in cord blood transplantation.


Assuntos
Apoptose/imunologia , Sangue Fetal/imunologia , Receptores do Fator de Necrose Tumoral/imunologia , Subpopulações de Linfócitos T/imunologia , Fator de Necrose Tumoral alfa/imunologia , Antígenos CD/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Técnicas de Cultura de Células , Relação Dose-Resposta Imunológica , Humanos , Recém-Nascido , Interleucina-2/imunologia , Ativação Linfocitária/imunologia , Receptores Tipo I de Fatores de Necrose Tumoral , Receptores Tipo II do Fator de Necrose Tumoral
7.
J Immunol ; 167(5): 2972-8, 2001 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-11509647

RESUMO

Cytotoxic T lymphocytes (Tc) play a central role in cellular immunity against cancers. The cytotoxic potential of freshly isolated tumor-infiltrating lymphocytes (TILs) is usually not expressed. This suggests the possible existence of as yet unspecified and perhaps complex immunosuppressive factors or cytokines that affect the anti-tumor capacity of these TILs in the tumor milieu. In the present study, we demonstrated for the first time that TILs derived from human cervical cancer tissue consist mainly of Th2/Tc2 phenotypes. In vitro kinetic assays further revealed that cancer cells could direct the tumor-encountered T cells toward the Th2/Tc2 polarity. Cancer cells promote the production of IL-4 and down-regulate the production of IFN-gamma in cancer-encountered T cells. The regulatory effects of cervical cancer cells are mediated mainly by IL-10, and TGF-beta plays only a synergistic role. The cancer-derived effects can be reversed by neutralizing anti-IL-10 and anti-TGF-beta Abs. IL-10 and TGF-beta are present in cancer tissue and weakly expressed in precancerous tissue, but not in normal cervical epithelial cells. Our study strongly suggests important regulatory roles of IL-10 and TGF-beta in cancer-mediated immunosuppression.


Assuntos
Linfócitos do Interstício Tumoral/imunologia , Linfócitos T Citotóxicos/imunologia , Células Th2/imunologia , Neoplasias do Colo do Útero/imunologia , Citocinas/biossíntese , Citocinas/genética , Feminino , Humanos , Tolerância Imunológica , Imunidade Celular , Técnicas In Vitro , Interleucina-10/biossíntese , Interleucina-10/genética , Interleucina-10/imunologia , Interleucina-10/farmacologia , Linfócitos do Interstício Tumoral/patologia , Testes de Neutralização , Fenótipo , Proteínas Recombinantes/farmacologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/patologia , Linfócitos T Citotóxicos/patologia , Células Th2/patologia , Fator de Crescimento Transformador beta/biossíntese , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/imunologia , Fator de Crescimento Transformador beta/farmacologia , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia
8.
Lupus ; 10(7): 461-5, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11480842

RESUMO

For centuries, Chinese medicine has regarded Ganoderma, a fungus (Myceteae, Amastigomycota, Busidomycetes, Aphyllophorales, Polyporaceae, Ganoderma) also known as 'Ling Zhi' in Mandarin, as a premium remedy for many diseases. Until now, no convincing data regarding its therapeutic effects in vivo on autoimmune diseases have been demonstrated. In this study, a controlled protocol was conducted in which New Zealand Black/White F1 mice were fed standard chow with prednisolone (0.5 mg/kg/day) or Ganoderma tsugae extract, commencing at 2 months of age. It was found that the F1 mice responded well to Ling Zhi extract. Ling Zhi improved the survival rate of lupus mice, decreased the amount of proteinuria, decreased serum levels of anti-dsDNA autoantibody, and showed evidence of decreased perivascular and parenchyma mononuclear cell infiltration in vital organs.


Assuntos
Autoanticorpos/biossíntese , Medicamentos de Ervas Chinesas/farmacologia , Medicina Tradicional Chinesa , Animais , Anticorpos Antinucleares/sangue , Rim/patologia , Fígado/patologia , Pulmão/patologia , Camundongos , Camundongos Endogâmicos NZB , Proteinúria/prevenção & controle , Reishi , Taxa de Sobrevida
9.
Cancer Res ; 61(1): 237-42, 2001 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11196168

RESUMO

Depressed immune responses have been observed frequently in cancer patients. In a variety of human malignancies, the expression of interleukin-2 receptor alpha (IL-2R alpha) on activated tumor-infiltrating lymphocytes was down-regulated. Because IL-2R alpha plays a pivotal role in the development and propagation of functional T cells, its depressed expression may result in poor function of tumor-reactive cytotoxic lymphocytes. For elucidating the mechanism responsible for down-regulation of IL-2R alpha, a coculture model of in vitro mixed autologous lymphocytes and tumor cells was established. Kinetic analysis showed that cervical cancer cells down-regulated IL-2R alpha expression on encountered T cells. The amount of IL-2R alpha mRNA in tumor-infiltrating lymphocytes-derived CD8+ T cells was compatible with that in the corresponding activated CD8+ T cells. Additional evidence showed that cervical cancer cells could induce the release of soluble IL-2R alpha expression on encountered T cells. By using protease inhibition assays we demonstrated that tissue inhibitors of metalloproteinase abrogated the cancer-mediated IL-2R alpha proteolytic process and restored the T-cell proliferation function. Immunohistochemical stainings further revealed prominent metalloproteinase (MMP) expressions, including MMP-1, MMP-2, and MMP-9, in cervical cancer tissues. Additional in vitro studies showed that MMP-9 mediates cleavage of IL-2R alpha and down-regulates the proliferative capability of cancer-encountered T cells. Our findings suggest a new role of MMPs in tumor-mediated immunosuppression and provide a possible therapeutic potential for patients with cervical cancer.


Assuntos
Metaloendopeptidases/imunologia , Receptores de Interleucina-2/imunologia , Neoplasias do Colo do Útero/enzimologia , Neoplasias do Colo do Útero/imunologia , Colo do Útero/citologia , Técnicas de Cocultura , Regulação para Baixo , Células Epiteliais , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Tolerância Imunológica/imunologia , Interleucina-2 , Isoenzimas/biossíntese , Ativação Linfocitária/imunologia , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Metaloendopeptidases/antagonistas & inibidores , Metaloendopeptidases/metabolismo , Receptores de Interleucina-2/biossíntese , Receptores de Interleucina-2/metabolismo , Células Estromais , Linfócitos T/imunologia , Linfócitos T/metabolismo , Inibidor Tecidual de Metaloproteinase-1/farmacologia , Inibidor Tecidual de Metaloproteinase-2/farmacologia , Transcrição Gênica
10.
Toxicology ; 152(1-3): 47-52, 2000 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-11090939

RESUMO

(1-->3)-beta-D-glucan is a polyglucose structure in the cell wall of moulds, some bacteria and plants. Due to its unique (1-->3)-beta linkage it binds to specific receptors on phagocytosing cells and induces changes in their metabolism. Under realistic environmental concentrations, available data suggest that these changes express themselves as alterations of the defense mechanisms to other agents. Inhalation of (1-->3)-beta-D-glucan in humans causes symptoms from the upper respiratory tract and induction of cytokines in blood monocytes. (1-->3)-beta-D-glucan can be used as a marker of mould biomass in field studies. Relationships between the amount of (1-->3)-beta-D-glucan and the extent of symptoms as well as lung function changes and inflammatory markers have been described. In view of the mechanisms involved in the normal development of the immune system, children seem to be a particular group at risk due to (1-->3)-beta-D-glucan exposure.


Assuntos
Poluição do Ar em Ambientes Fechados/efeitos adversos , Asma/etiologia , Glucanos/toxicidade , Hipersensibilidade/etiologia , beta-Glucanas , Animais , Glucanos/química , Humanos , Imunidade/efeitos dos fármacos
11.
J Biomed Sci ; 7(4): 317-21, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10895055

RESUMO

Aging is associated with a decline in immune function. Interferon-gamma (IFN-gamma) and interleukin-4 (IL-4), two important immune deviation-related cytokines, are mainly produced by type 1 and type 2 T cells, respectively. To investigate the age-associated changes in the secretion of these two cytokines, 20 elderly and 20 young subjects fulfilling the SENIEUR protocol were enrolled. The ratios of CD4+ to CD8+ T cells were not different between the two age groups. The CD4+ and CD8+ T cells were purified by a magnetic cell sorting system, and then activated by concurrent anti-CD3 and anti-CD28 stimulation. The released cytokines were determined by ELISA. Both the CD4+ and the CD8+ T cells of the elderly individuals secreted a significantly larger amount of IFN-gamma after activation. Profound IL-4 production by CD8+ T cells was observed in the older subjects compared with that of the young subjects. These data suggested that age-associated decrease in immunity may be related to an imbalance in the secretion of immune deviation cytokines. The number of IL-4-secreting CD8+ T cells (T cytotoxic 2) rose significantly in the older individuals. Our design also provided a useful way to differentiate the T cell subsets secreting the same cytokine, such as IFN-gamma-producing T helper 1 and T cytotoxic 1 cells.


Assuntos
Envelhecimento/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Interferon gama/metabolismo , Interleucina-4/metabolismo , Adolescente , Adulto , Idoso , Relação CD4-CD8 , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Humanos , Interferon gama/biossíntese , Interleucina-4/biossíntese , Ativação Linfocitária/imunologia , Masculino
12.
Clin Exp Allergy ; 30(4): 538-45, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10718851

RESUMO

BACKGROUND: House dust mite (HDM) Dermatophagoides pteronyssinus is the most important source of indoor allergens that cause allergic diseases in Taiwan. We prepared purified HDM allergens (Der p 1, Der p 2 and Der p 5) to detect allergen-specific immunoglobulin (Ig) E responsiveness among a large number of test subjects. The robust genetic typing system for HLA class II genes also facilitated the study on association of HLA and allergic response toward HDM. OBJECTIVE: This study intended to investigate the association between HLA class II alleles and the IgE responsiveness to the major allergens from HDM, D. pteronyssinus. METHODS: Two hundred and forty-eight subjects were selected for HLA association study. Plasma HDM allergen (Der p 1, Der p 2, Der p 5) -specific IgE and Der p 2-specific IgG antibodies were detected by ELISA, while HLA class II -DRB1, -DQA1, -DQB1, -DPB1 genetic polymorphism was determined by polymerase chain reaction/sequence-specific oligonucleotide probe hybridization (PCR/SSOPH). Statistical comparison of the allelic distribution of each HLA class II genes among the individuals with/without HDM allergen-specific IgE and IgG antibodies were performed. RESULTS: There was no significant association between HLA DRB1, DQB1, DQA1 alleles and HDM-specific IgE responsiveness noted. Only DRB1*0803 and the linked DQA1*0103 alleles showed positive association with Der p 5-specific IgE responsiveness. However, we found that HLA-DPB1*1301 predisposed subjects to IgE responsiveness to HDM Der p 5. HLA DPB1*0501 was weakly associated with the IgE responsiveness to HDM Der p 1 and Der p 5. There was a strong negative association between the HLA-DPB1*0201 allele with IgE responsiveness to Der p 1 (OR: 0.30, P

Assuntos
Alérgenos , Poeira , Glicoproteínas/imunologia , Antígenos HLA-DP/genética , Hipersensibilidade/genética , Hipersensibilidade/imunologia , Imunoglobulina E/imunologia , Ácaros , Adulto , Alelos , Animais , Antígenos de Dermatophagoides , Feminino , Ligação Genética , Antígenos HLA-DP/imunologia , Cadeias beta de HLA-DP , Humanos , Hipersensibilidade/epidemiologia , Masculino , Taiwan
13.
Environ Res ; 82(3): 239-44, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10702331

RESUMO

The in vivo effect of methylcyclopentadienyl manganese tricarbonyl (MMT), an organic manganese-containing compound, on the mouse motor nerve was studied. The motor nerve conduction velocity was markedly decreased in MMT-treated mice. The Na(+),K(+)-ATPase activity of sciatic nerve isolated from MMT-treated mice was decreased; however, the sciatic nerve Na(+),K(+)-ATPase activity was not affected by the in vitro treatment of MMT. Moreover, [(3)H]ouabain binding of sciatic nerve isolated from MMT-treated mice was decreased. Using Western blot analysis, the amount of Na(+),K(+)-ATPase catalytic alpha1 subunit polypeptide in sciatic nerve of MMT-treated mice was also decreased. These results indicate that a causal relationship may exist between reduced nerve Na(+),K(+)-ATPase activity and motor nerve conduction velocity in MMT-treated mice and that a measurable decrease in alpha1 catalytic subunit isoform of Na(+),K(+)-ATPase may be necessary for the development of peripheral neuropathy by MMT.


Assuntos
Condução Nervosa/efeitos dos fármacos , Compostos Organometálicos/efeitos adversos , Nervo Isquiático/enzimologia , ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Isoenzimas , Camundongos , Ouabaína , Nervo Isquiático/efeitos dos fármacos
14.
Clin Exp Allergy ; 30(3): 426-32, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10691903

RESUMO

BACKGROUND AND OBJECTIVE: Repeated exposure of aerosolized antigen via respiratory tract can induce immunoglobulin (Ig) E isotype-specific tolerance to this antigen. However, the atopic individuals often produce a higher titre of IgE in response to airborne environmental allergens. The mechanisms of this differential regulation of airway allergen-specific immune responses are not fully understood. This study investigated the role of airborne endotoxin on the initiation of antigen-specific airway allergic responses. METHODS: ELISA methods for detection of isotypes of antigen-specific antibodies and competitive reverse transcription polymerase chain reaction for detection mRNA of cytokines were used. In addition, Liu stain method was used to analyse the amounts of eosinophils in bronchoalveolar lavage fluid. RESULTS: Mice pre-exposed with airborne endotoxin mounted significantly higher amounts of OVA-specific IgE antibody responses to inhaled OVA than those OVA-only sensitized mice. Inhaled endotoxin could downregulate repeated airway antigen exposure-induced IgE isotype-specific tolerance and increase antigen-induced lung eosinophils infiltration. CONCLUSIONS: These data show that airborne endotoxin exposure could potentiate allergen-specific airway inflammation. The results should have potential implications for understanding the development of allergen-induced airway allergic responses.


Assuntos
Alérgenos/efeitos adversos , Asma/etiologia , Escherichia coli , Lipopolissacarídeos/administração & dosagem , Ovalbumina/imunologia , Aerossóis , Animais , Asma/genética , Asma/imunologia , Líquido da Lavagem Broncoalveolar/citologia , Citocinas/biossíntese , Citocinas/genética , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Eosinófilos/imunologia , Feminino , Imunoglobulina E/análise , Imunoglobulina G/análise , Contagem de Leucócitos , Pulmão/imunologia , Camundongos , Camundongos Endogâmicos BALB C , RNA Mensageiro/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa
15.
Am J Ophthalmol ; 128(5): 554-65, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10577522

RESUMO

PURPOSE: To quantify automated visual field defects seen at entry in the Optic Neuritis Treatment Trial (ONTT) to determine whether particular areas of the field are preferentially affected and to determine the extent of visual field involvement in patients having "localized" field defects. METHODS: Review of Humphrey 30-2 Visual Field (Allergan-Humphrey, Inc, San Leandro, CA) data from the involved and fellow eyes of 440 patients who were enrolled in the ONTT. Field defects were evaluated by comparing the involved eye to the fellow eye. RESULTS: Patients with diffuse visual field defects had a relatively equal diminution of visual threshold throughout the tested 30-2 field. Patients with localized central and cecocentral scotomas had their greatest depression of threshold centrally; however, even those patients with mild defects (mean defect, <6 dB) had diminution of visual threshold throughout the entire tested 30-degree field. Patients with moderate (mean defect, 6 to 20 dB) and severe (mean defect, >20 dB) central and cecocentral defects had even greater peripheral depression. Patients with altitudinal or quadrant defects had involvement of the "unaffected" field that also varied with the mean defect. The overall average depression of visual threshold for all patients averaged 36%+/-4% and was relatively uniform throughout the tested field. CONCLUSIONS: Optic neuritis affects the entire central 30-2 field, even in patients who appear to have localized depression of visual threshold. Optic neuritis does not appear to have a predilection for any particular area of the visual field.


Assuntos
Neurite Óptica/fisiopatologia , Campos Visuais , Doença Aguda , Humanos , Neurite Óptica/complicações , Escotoma/etiologia , Escotoma/fisiopatologia , Limiar Sensorial , Transtornos da Visão/etiologia
16.
Am J Ophthalmol ; 128(5): 566-72, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10577523

RESUMO

PURPOSE: To assess the pattern of recovery of the visual field of patients with optic neuritis and to determine whether all affected portions of the visual field recover similarly or certain portions of the visual field have greater recovery. METHODS: We reviewed the Humphrey Visual Field (Allergan-Humphrey Inc, San Leandro, California) data from the initial and 6-month examination for the involved and fellow eyes of patients enrolled in the Optic Neuritis Treatment Trial (ONTT). The average threshold for each patient was calculated for the entire tested field and for locations within concentric rings having a radius 3, 9, 15, 21, and 27 degrees from fixation. The absolute amount of improvement and percentage improvement in average threshold between entry and the 6-month follow-up examination were determined for each patient. These measurements were compared within the concentric rings to assess patterns of recovery. RESULTS: Patients with localized defects recovered 86%+/-20% of their initial defect in average threshold, whereas those having diffuse defects recovered an average of 85%+/-23%. The area about fixation had the greatest relative recovery of threshold (87%+/-21% at 3 degrees); the relative recovery decreased with increasing eccentricity from fixation (P<.01). CONCLUSIONS: Patients with optic neuritis have a marked return of visual field function that does not appear to differ between patients with diffuse or localized field defects. The reduced redundancy of axons in the periphery of the field compared with near fixation may be responsible for the greater relative recovery of threshold near fixation.


Assuntos
Neurite Óptica/tratamento farmacológico , Neurite Óptica/fisiopatologia , Campos Visuais , Fixação Ocular , Humanos , Recuperação de Função Fisiológica , Limiar Sensorial
17.
Cancer ; 86(8): 1537-43, 1999 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-10526283

RESUMO

BACKGROUND: To investigate the clinical significance of tumor-infiltrating lymphocytes (TILs) within the tumor milieu of human cervical carcinoma, the authors quantitatively measured and compared the subpopulations of lymphocytes infiltrating the neoplastic cervix. METHODS: A total of 30 patients with Stage Ia-IIa cervical carcinoma were enrolled. TILs were isolated from tissue specimens by means of a mechanical dispersal technique, and the immunocyte subsets were quantified with dual-color flow cytometry. Bulky tumor was defined as tumor size >4 cm in greatest dimension according to the 1995 staging of the International Federation of Gynecology and Obstetrics. RESULTS: The CD4/CD8 ratios of TILs were reversed in both cervical squamous cell carcinoma (n = 20) and cervical adenocarcinoma (n = 10). The proportion of CD4(+) T cells was significantly lower in tumors from patients with lymph node metastasis (n = 8) than in those from patients without lymph node metastasis (n = 22) (24.5 vs. 32.7, P = 0.001), as was the reversed CD4/CD8 ratio (0.50 vs. 0.81, P = 0.001). The proportion of CD4(+) T cells was much lower in bulky tumors (n = 5) than in nonbulky tumors (n = 25) (21.4 vs. 32.5, P < 0.001), reflecting in a more strongly reversed CD4/CD8 ratio (0.41 vs. 0.81, P = 0.001). CONCLUSIONS: Decreased proportions of tumor-infiltrating CD4+ T cells with reversed CD4/CD8 ratios are highly correlated with rapid tumor growth and lymph node metastasis in cervical carcinoma. The regional immune escape is of prognostic importance with regard to cancer progression.


Assuntos
Adenocarcinoma/imunologia , Relação CD4-CD8 , Carcinoma de Células Escamosas/imunologia , Linfócitos do Interstício Tumoral/imunologia , Neoplasias do Colo do Útero/imunologia , Adenocarcinoma/patologia , Antígenos CD4/análise , Antígenos CD8/análise , Carcinoma de Células Escamosas/patologia , Progressão da Doença , Feminino , Humanos , Imunofenotipagem , Células Matadoras Naturais/citologia , Células Matadoras Naturais/imunologia , Linfonodos/imunologia , Linfonodos/patologia , Metástase Linfática , Contagem de Linfócitos , Subpopulações de Linfócitos/citologia , Subpopulações de Linfócitos/imunologia , Linfócitos do Interstício Tumoral/citologia , Estadiamento de Neoplasias , Neoplasias do Colo do Útero/patologia
18.
Eur J Immunol ; 29(8): 2491-7, 1999 08.
Artigo em Inglês | MEDLINE | ID: mdl-10458763

RESUMO

Repeated inhalation of allergen leads to the down-regulation of allergen-specific IgE responses in non-atopic individuals as well as in mice. This phenomenon is named inhalation-induced IgE tolerance. In contrast, inhaled allergen causes significant IgE and allergic responses in atopic persons. The mechanisms involved in this differential regulation of airway allergen-specific immune responses remain unclear. Besides the allergen exposure of genetically susceptible individuals, environmental contamination is considered to play a role as an initiating factor for airway allergic responses. Using a murine model, we demonstrate here that airborne beta-1, 3-D-glucan, which exists frequently in our environment, particularly in highly humid areas, can abrogate inhalation-induced IgE isotype-specific down-regulation and promote airway eosinophil infiltration to inhaled antigen.


Assuntos
Alérgenos/administração & dosagem , Glucanos/administração & dosagem , Glucanos/imunologia , beta-Glucanas , Administração por Inalação , Animais , Antígenos de Fungos/administração & dosagem , Sequência de Bases , Primers do DNA/genética , Eosinófilos/imunologia , Eosinófilos/patologia , Feminino , Humanos , Hipersensibilidade Imediata/etiologia , Imunização , Imunoglobulina E/sangue , Imunoglobulina G/sangue , Interleucina-10/genética , Interleucina-12/genética , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/imunologia , RNA Mensageiro/biossíntese , RNA Mensageiro/genética
19.
Clin Exp Allergy ; 29(2): 271-9, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10051733

RESUMO

BACKGROUND AND OBJECTIVE: Allergic contact dermatitis and its animal model, contact hypersensitivity (CHS), have long been documented as type 1 T-cell-predominant immune responses. Although type 1/type 2 T-cell deviation has been repeatedly demonstrated to play an important role in many human diseases and their animal models, the potential of tilting type 1/type 2 T-cell differentiation of CHS by modulating the manner of administration and dosage of hapten remains unexplored. This study examined the effect of these two factors on type 1/type 2 balance of CHS. METHODS: ELISA methods for detection of isotypes of hapten-specific antibodies and cytokine profiles of in vitro reactivation culture as well as ear-swelling assay were used to indicate type 1 or type 2 T-cell immune responses. RESULTS: In this paper, it was demonstrated that dosage of hapten has no effect on the type 1/ type 2 T-cell balance of CHS, whereas epicutaneous administration of hapten through patch application could tilt the type 1/type 2 balance to decrease type 1 and to augment type 2 T-cell responses. Patch application-induced modulation is still effective in ever-sensitized mice and the augmented type 2 T-cell responses are persistent and increase progressively in strength after repeated immunizations. Moreover, it was demonstrated that the augmented type 2 T-cell response can downregulate the elicitation of CHS. The major mediating cells of the enhanced type 2 T-cell responses were determined to be CD4+ T cells (TH2 cells). CONCLUSIONS: These data show that epicutaneous administration of hapten through patch application augments TH2 response which can downregulate the elicitation of murine CHS. This exploration may contribute to the understanding of regulatory mechanisms involved in contact allergy.


Assuntos
Dermatite Alérgica de Contato/imunologia , Regulação para Baixo/imunologia , Cloreto de Picrila/administração & dosagem , Pele/efeitos dos fármacos , Células Th2/imunologia , Transferência Adotiva , Animais , Citocinas/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Linfonodos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Testes do Emplastro , Baço/metabolismo , Células Th1/imunologia
20.
AIDS Res Hum Retroviruses ; 15(1): 43-50, 1999 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-10024051

RESUMO

To study the association between anti-Gag and anti-Nef antibody reactivities and their correlations with disease progression, 174 HIV-1/AIDS patients were followed up for 1 year after they received triple therapy. The antibody reactivities were analyzed using a Western blot test with recombinant Gag and Nef proteins. The results showed that decreasing levels of anti-Gag or anti-Nef antibody correlate with disease progression defined by HIV-1 viral loads or T4 cell counts. After receiving triple treatment for 1 year, 8 of 38 (21.1%) Nef antibody-negative patients became positive, while only 9 of 125 (7.2%) Nef antibody-positive persons lost the antibody reactivity (p < 0.01). Therefore, HIV-1 Nef may serve as a clinical marker of disease progression.


Assuntos
Produtos do Gene nef/imunologia , Anticorpos Anti-HIV/sangue , Infecções por HIV/imunologia , HIV-1/fisiologia , Carga Viral , Western Blotting , Contagem de Linfócito CD4 , Progressão da Doença , Produtos do Gene gag/imunologia , HIV-1/isolamento & purificação , Humanos , RNA Viral/sangue , Proteínas Recombinantes de Fusão/metabolismo , Produtos do Gene nef do Vírus da Imunodeficiência Humana
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