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1.
Exp Parasitol ; 134(4): 413-21, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23707346

RESUMO

The most active metabolite of vitamin D, 1,25(OH)2D3 is a steroid hormone implicated in a wide range of cell functions such as differentiation, proliferation and apoptosis. Leishmania mexicana causes two kinds of cutaneous leishmaniasis: localized or diffuse. In this work we explored the effect of treatment of 1,25(OH)2D3 on a susceptible leishmaniasis mice model. A significant reduction in the lesion size was found in animals treated with 1,25(OH)2D3. Well preserved tissue and presence of large numbers of eosinophils and fibroblasts was found in the group treated with 1,25(OH)2D3. By contrast, destroyed epidermis was observed with large amount of neutrophils and epithelioid macrophages, on infected groups without 1,25(OH)2D3 treatment. The production of pro-inflammatory cytokines in mice infected and treated with 1,25(OH)2D3 was lower than the animals infected without 1,25(OH)2D3 treatment. Interestingly, there were no differences in the number of parasites in both groups. Finally, the amount of collagen was higher in animals with treatment compare with animals without 1,25(OH)2D3 treatment. In summary, mice treated with 1,25 (OH) 2D3 reflect a healing process without elimination of L. mexicana.


Assuntos
Calcitriol/administração & dosagem , Leishmania mexicana , Leishmaniose Cutânea/tratamento farmacológico , Animais , Calcitriol/farmacologia , Calcitriol/uso terapêutico , Colágeno/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Imuno-Histoquímica , Injeções Intraperitoneais , Leishmania mexicana/efeitos dos fármacos , Leishmaniose Cutânea/imunologia , Leishmaniose Cutânea/patologia , Camundongos , Camundongos Endogâmicos BALB C , Pele/parasitologia , Pele/patologia
2.
Heliyon ; 9(5): e16088, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37215868

RESUMO

Traumatic brain injury (TBI) represents a significant public health concern and has been associated with high rates of morbidity and mortality. TBI generates two types of brain damage: primary and secondary. Secondary damage originates a series of pathophysiological processes, which include metabolic crisis, excitotoxicity, and neuroinflammation, which have deleterious consequences for neuronal function. However, neuroprotective mechanisms are also activated. The balance among these tissue responses, and its variations throughout the day determines the fate of the damage tissue. We have demonstrated less behavioral and morphological damage when a rat model of TBI was induced during the light hours of the day. Moreover, here we show that rats subjected to TBI in the dark lost less body weight than those subjected to TBI in the light, despite no change in food intake. Besides, the rats subjected to TBI in the dark had better performance in the beam walking test and presented less histological damage in the corpus callosum and the cingulum bundle, as shown by the Klüver-Barrera staining. Our results suggest that the time of day when the injury occurs is important. Thus, this data should be used to evaluate the pathophysiological processes of TBI events and develop better therapies.

3.
Mycopathologia ; 168(2): 95-100, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19360479

RESUMO

A second case of histoplasmosis in a captive mara (Dolichotis patagonum) from a colony at the wildlife park Africam Safari, Puebla, Mexico, is described, and the mara died with disseminated clinical form of the disease, affecting mostly the large intestine and adrenal. The pathological findings of this case 2 revealed severe granulomatous typhlocolitis and moderate granulomatous gastrohepatic lymphadenitis with numerous yeast-like cells, 2-4 mum in diameter, with a clear halo surrounding them inside the cytoplasm of macrophages, suggesting the parasitic form of Histoplasma capsulatum. Adrenocortical cells had abundant similar microorganisms in their cytoplasm without any associated lesion. Gomori's methenamine silver and periodic acid Schiff stained positively these microorganisms. Immunohistochemistry, using a rabbit anti-H. capsulatum serum, and transmission electron microscopy supported the diagnosis of H. capsulatum infection.


Assuntos
Histoplasma/isolamento & purificação , Histoplasmose/veterinária , Roedores/parasitologia , Glândulas Suprarrenais/parasitologia , Glândulas Suprarrenais/patologia , Animais , Citoplasma/parasitologia , Histocitoquímica/métodos , Histoplasmose/patologia , Imuno-Histoquímica/métodos , Intestino Grosso/patologia , Linfonodos/parasitologia , Linfonodos/patologia , Macrófagos/parasitologia , Masculino , México , Microscopia Eletrônica de Transmissão , Coloração e Rotulagem/métodos
4.
Nutr Hosp ; 24(5): 558-67, 2009.
Artigo em Espanhol | MEDLINE | ID: mdl-19893866

RESUMO

INTRODUCTION: As eating disorders include both psychological and physiological components, appropriate management of these disorders requires input from a number of disciplines working together in a coordinated manner, following an integrated Programme. The Eating Disorders-Nutrition Education Programme has as its purpose achieving healthier habits and modifying eating behaviour. The Programme should take place as one part of Eating Disorders treatment. OBJECTIVES: To determine the efficacy of a Nutrition Education Programme about nutritional state and eating patterns in a group of patients diagnosed with Eating Disorders who follow the usual check-up protocol in the clinic for nutrition and mental health. MATERIAL AND METHODS: 89 patients were included, including 5% men. They received individual nutritional education with weekly/fortnightly appointments during a period of 4-6 months. Educational counseling was carried out by a dietician. The mean age of the sample was 24 +/- 8 years and the diagnoses were: Anorexia Nervosa Restrictive (ANR) 32.5% Anorexia Nervosa Purgative (ANP) 26.5%, Bulimia Nervosa (BN) 18%, Eating Disorder Not Otherwise Specified (EDNOS) 21% and Binge Eating Disorder (BED) 2%. The average evolution time since the diagnosis was 4.8 +/- 5 years. An anthropometric assessment, assessment of daily oral intake, 24-hour dietary recall, and Eating Attitudes Test (EAT26) questionnaires were completed at the first appointment and again at the end of the programme. RESULTS: The mean score of the EAT26 questionnaire was 32 +/- 15 initially, and after 4-6 months the score was 23.7 +/- 14 (p < 0.001). This change represents a significant improvement in the patients' symptoms after the Programme. Furthermore there were significant differences in the evaluation of the questionnaire by scales and by diagnosis. After 4-6 months, there was a meaningful reduction in episodes of vomiting per week (from 7.5 +/- 10 to 1 +/- 1.8 p < 0.001) in ANP and BN binge-purging (8 +/- 9.7 vs 2.2 +/- 3.2 p < 0,01). In addition, a favourable trend in the number of binges per week was observed for both diagnoses. The percentage of subjects that ate less than 4 meals per day decreased from 70% to 19% after the Education Programme (p < 0.001). Some 67% of the patients dedicated a specific time for eating and a 54% started to have complete meals. These results that show a very favourable tendency with respect to the normalization of eating patterns. There was improvement in the intake of dairy products, vegetables, fruits, cereals and oil (p < 0.05). At the beginning, 34% consumed at least 3 of the 6 food groups within the recommended range, but at the end 70% did (p < 0.001). After the nutritional education programme, an important increase in energy ingestion and carbonhydrate consumption took place (p < 0.001), as much with ANR as with ANP. With respect to micronutrients, the ingestion of vitamin B2 significantly increased, as well as folic acid and calcium (p < 0.001) in ANP, and magnesium and calcium (p < 0.001) in ANR. In ANR, we found a significant improvement in nutritional status (p < 0.001). Variables including weight, BMI, muscular circumference of the arm and tricipetal fold were at the limit of significance. Regarding ANP and EDNOS, the initial evaluation demonstrated that they were within normal limits, and they were maintained after nutritional education. In BN, progress towards normalization of BMI took place, increasing from 26.4 +/- 6.6 to 25.5 +/- 5.7 (-2.3 kg). CONCLUSIONS: The Nutritional Education Programme carried out by qualified professionals should be a part of Eating Disorders treatment, along with medical and psychological monitoring and as part of an interdisciplinary, multiprofessional team effort.


Assuntos
Transtornos da Alimentação e da Ingestão de Alimentos/terapia , Educação de Pacientes como Assunto , Feminino , Humanos , Masculino , Estado Nutricional , Avaliação de Programas e Projetos de Saúde , Adulto Jovem
5.
Rev Argent Microbiol ; 41(2): 102-4, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19623900

RESUMO

Histoplasma capsulatum was isolated from the spleen of a first infected mara (Dolichotis patagonum) and from a second mara's liver and adrenal gland, both in the same colony at the Africam Safari, Puebla, Mexico. Studies of H. capsulatum isolates, using nested-PCR of a 100-kDa protein coding gene (Hcp100) fragment and a two-primer RAPD-PCR method, suggest that these isolates were spreading in the environment of the maras' enclosure. By using a Dot-ELISA method, sera from mice inoculated with three homogenates of soil samples from the maras' enclosed space developed positive brown spot reactions to a purified H. capsulatum antigen, which identified the probable source of the maras' infection.


Assuntos
Reservatórios de Doenças/microbiologia , Histoplasma/isolamento & purificação , Histoplasmose/veterinária , Doenças dos Roedores/microbiologia , Roedores/microbiologia , Glândulas Suprarrenais/microbiologia , Animais , Aves/microbiologia , Quirópteros/microbiologia , DNA Fúngico/análise , Fezes/microbiologia , Histoplasma/classificação , Histoplasma/genética , Histoplasmose/epidemiologia , Histoplasmose/microbiologia , Abrigo para Animais , Fígado/microbiologia , México/epidemiologia , Camundongos , Reação em Cadeia da Polimerase , Técnica de Amplificação ao Acaso de DNA Polimórfico , Doenças dos Roedores/epidemiologia , Microbiologia do Solo , Baço/microbiologia
6.
Parasite Immunol ; 30(8): 425-34, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18507782

RESUMO

The regulatory effect of mast cells on the pathogenesis of leishmaniasis is unclear. We report a comparative analysis of TLR2 membrane expression, TNF-α, IL-10 and MIP-1α production, and granule release of bone marrow-derived mast cells (BMMCs) from susceptible BALB/c and resistant C57BL/6 mice, stimulated in vitro with Leishmania mexicana lipophosphoglycan (LPG). We studied the kinetics of mast cell degranulation and parasite numbers in lesions of both mouse strains infected with L. mexicana. We found that BMMCs of C57BL/6 mice expressed more TLR2 and produced higher levels of both cytokines and MIP-1α, whereas BALB/c BMMCs significantly augmented their granule release. Lesions of BALB/c mice showed higher levels of degranulated mast cells at 3 h of infection, whereas after 3 days of infection, the number of degranulated mast cells in C57BL/6 was higher than in BALB/c lesions. Throughout infection, BALB/c mice harboured more parasites. The regulatory effect of mast cells seems to depend on the genetic background of the host: mast cells of BALB/c mice facilitate disease progression due to an augmented inflammatory response early in the infection, whereas mast cells of C57BL/6 mice produce cytokines that regulate inflammation and maintain an elevated number of immune cells in the lesions, promoting disease control.


Assuntos
Glicoesfingolipídeos/imunologia , Leishmania mexicana/imunologia , Leishmania mexicana/patogenicidade , Leishmaniose Cutânea/genética , Leishmaniose Cutânea/imunologia , Mastócitos/imunologia , Animais , Contagem de Células , Degranulação Celular , Quimiocina CCL3/biossíntese , Modelos Animais de Doenças , Interleucina-10/biossíntese , Leishmaniose Cutânea/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Doenças dos Roedores/genética , Doenças dos Roedores/imunologia , Doenças dos Roedores/patologia , Pele/parasitologia , Pele/patologia , Receptor 2 Toll-Like/biossíntese , Fator de Necrose Tumoral alfa/biossíntese
7.
Vaccine ; 35(42): 5653-5661, 2017 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-28890195

RESUMO

GK-1 is a parasite-derived peptide adjuvant of 18 amino acid-length that enhances T-cell function and increases survival in B16-F10 melanoma tumor-bearing mice. This study was designed to evaluate in vivo the antitumor efficacy of GK-1 on 4T1 mouse mammary carcinoma. BALB/c mice with palpable primary tumors were weekly intravenously injected three times with saline solution or three different concentrations (10, 50, or 100µg per mouse) of GK-1. GK-1 significantly increased lifespan (p<0.0001) and reduced the primary tumor weight (p=0.014) and volume (p<0.0001) with respect to control mice, with no statistically significant differences among GK-1 doses. At the primary tumor, we found increased necrotic areas associated with a reduction in tumor mass, as well as an increase in the antitumor cytokine IL-12. Especially encouraging is the ability of GK-1 to reduce the number of lung metastasis (p=0.006) disregarding the dose used. The participation of IL-6 in metastasis development and the decreased levels of CCL-2, CCL-3, TNF-α, CXCL-9, GM-CSF, and b-FGF found in lungs of GK-1-treated mice is discussed. Our study supports the effectiveness of GK-1 as an antineoplastic agent that merits further exploration in combination with other therapeutic approaches in future translational studies.


Assuntos
Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Neoplasias Mamárias Animais/tratamento farmacológico , Metástase Neoplásica/patologia , Peptídeos Cíclicos/farmacologia , Animais , Neoplasias da Mama , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos , Interleucina-12/metabolismo , Interleucina-6/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Fator de Necrose Tumoral alfa/metabolismo
8.
Virusdisease ; 28(1): 102-110, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28466061

RESUMO

This is a first report in Mexico of the presence of antibodies against respiratory syncytial virus (RSV) and parainfluenza-3 virus in Mexican sheep in different productive stages. We determine the association of serological positivity with age and production system, and obtain molecular evidence of infection by both virus. RSV prevalence in adult sheep was 47% (49/105) at the tropic and 64% (63/99) at the uplands. A significant difference in RSV seropositivity between animals from the tropic and the uplands was observed (P < 0.05). Seropositivity correlated with production system (P = 0.003, OR = 2.042), with a risk of showing antibodies was 2.042 times higher in sheep under an extensive production system. A significant difference in PI3V seropositivity between animals from either provenance (P = 0.017, OR = 0.475) were also found, with a risk of showing antibodies 0.475 times higher in sheep under an extensive production system. Genetic material from RSV and PI3V was identified by RT-PCR in nasal swab samples from clinically healthy lambs and confirmed by sequencing and phylogenetic analysis. Serological results show that sheep are susceptible to infection by both viruses, and molecular results suggest that the identified antibodies are result of natural infections and reinfections.

9.
Dev Comp Immunol ; 19(3): 225-36, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8595821

RESUMO

In mammalian epidermis, Langerhans cells (LC) are the only antigen-presenting dendritic cells that possess the ectoenzyme adenosine triphosphase (ATPase) and constitutively express class II molecules encoded by the major histocompatibility complex. Recently, we demonstrated the presence of LC in chicken epidermis. The aim of the present study is to demonstrate the presence of LC-like cells in turtle Kinosternum integrum, epidermis by light and ultrastructural ATPase histochemistry. ATPase-positive dendritic cells were observed in epidermal sheets whose maximum mean number was 192 cells/mm2. Electron microscopy for ATPase stained sections showed an electrondense precipitate in the plasma membrane of dendritic clear cells located among basal and suprabasal keratinocytes, ultrastructurally similar to LC. In serial sections, some dendritic cells showed LC (Birbeck) granules. The present study demonstrates for the first time ATPase-positive dendritic cells, morphologically similar to LC, in reptilian epidermis.


Assuntos
Células de Langerhans/ultraestrutura , Pele/citologia , Tartarugas/anatomia & histologia , Adenosina Trifosfatases/análise , Animais , Histocitoquímica , Células de Langerhans/enzimologia , Pele/enzimologia , Pele/ultraestrutura
10.
Nutr Hosp ; 26(5): 1155-60, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22072367

RESUMO

BACKGROUND: The aim was to compare the differences in feelings of hunger and satiety in a group of overweight/obese women after eating a test meal with or without bread. PATIENTS AND METHODS: The study included 122 women (BMI≥25<40 kg/m²) who were randomly assigned to consume one of the following test meals: NO BREAD meal (2.40 MJ, 46% carbohydrates, 26% protein, 28% fat; which included rice or pasta) and BREAD meal (2.39 MJ, with equal caloric distribution and the same foods except with bread instead of rice or pasta). A visual analogue scale (VAS) was used, with 5 questions to be answered at different times: 1) just before eating, 2) just after eating and exactly 3) 60 and 4) 90 minutes after eating the test meal. The test was performed at the start and after 16 weeks of following a lifestyle modification program based on a low-calorie diet (with or without bread). RESULTS: 104 women completed the study (48.4±9.0 years) with a baseline BMI of 29.8±3.5 kg/m². At the start of the study there were no significant differences in any of the VAS parameters measured between the groups. After 16 weeks, BREAD group obtained higher scores in question 3 (referring to the sensation of satiety) that were significant at time 3 (7 versus 5; p<0.05) and time 4 (8 versus 4; p<0.01). CONCLUSIONS: The inclusion of bread in a low-calorie meal may result in a greater sensation of satiety after eating. These results contradict the recommendation to exclude bread from a food plan aimed at weight loss.


Assuntos
Pão , Restrição Calórica , Ingestão de Alimentos/fisiologia , Fome/fisiologia , Resposta de Saciedade/fisiologia , Adulto , Composição Corporal/fisiologia , Peso Corporal/fisiologia , Dieta , Carboidratos da Dieta , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Circunferência da Cintura/fisiologia , Adulto Jovem
11.
Nutr Hosp ; 26(1): 97-106, 2011.
Artigo em Espanhol | MEDLINE | ID: mdl-21519735

RESUMO

INTRODUCTION: Nutrition labelling (NL) provides information on the energy and nutrients in a food and it represents a valuable tool to help consumers make informed decisions about their diet and lifestyle. However, little is known about how consumers perceive the nutrition labelling information. OBJECTIVES: Evaluate the knowledge of NL of a population survey and examine aspects such as attention, reading, understanding and utility. MATERIAL AND METHODS: 200 volunteers were interviewed about NL on National Nutrition Day (NND) on May 28, 2010 at the La Paz University Hospital in Madrid. The questionnaire was self-administered and this contained 10 closed multiple choice questions. RESULTS: The surveyed group (66.7% women and 33.3% men) had a mean age of 42.0 ± 15 years and a BMI of 24.1 ± 3.8 kg/m². A percentage of 86.5% had completed secondary and higher education. The concept about NL was knocked by 77.1% of them. This percentage was significantly higher according to the level of their studies (primary 7.1%, secondary 32.1% and higher studies 60.9%; p < 0.0001) and also regarding the age range (42.3% vs. 25% of over that 50, p < 0.05). 73.8% always or almost always readied NL; 67.7% of those who declared that always readied were women and 71% had higher education. 53.8% of people over 50 years were not capable of reading labels due to the small letters. The most interesting information for the consumers was: calories (61%), fats (39%) and cholesterol (25.7%). Nutritional concepts questions had a low percentage of right answers, especially in volunteers with lower level of education and among older age groups. CONCLUSIONS: Results show that consumers have a low level of nutrition information that would enable a better choice to purchase food. Nutrition education is needed should be necessary to NL had a significant impact on the foods election. Therefore, this fact could contribute to the maintenance of health and disease prevention.


Assuntos
Rotulagem de Alimentos , Educação em Saúde , Adolescente , Adulto , Fatores Etários , Coleta de Dados , Feminino , Humanos , Conhecimento , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Fatores Sexuais , Espanha , Inquéritos e Questionários , Adulto Jovem
12.
Parasitol Res ; 102(4): 635-43, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18046577

RESUMO

In parasites of the order Kinetoplastida, such as Trypanosoma cruzi and Trypanosoma brucei, glycolysis is carried out by glycolytic enzymes in glycosomes. One of the glycolytic enzymes is triosephosphate isomerase (TIM), which in T. brucei is localized exclusively in glycosomes, whereas in T. cruzi, the localization of TIM has not been fully ascertained. In the present work, we made a monoclonal antibody (mAb 6-11G) against recombinant T. cruzi TIM (rTcTIM). Incubation of T. cruzi epimastigotes with the mAb inhibited parasite survival. Western blotting showed that the mAb recognized rTcTIM and a 27 kDa band in T. cruzi lysates that corresponded to TcTIM. Sera from patients with Chagas disease recognized rTcTIM and cross-reacted with human recombinant TIM. The cross reactivity between parasite and human TIM possibly contributes to the autoimmune pathogenesis of Chagas disease. Electron microscopy of T. cruzi epimastigotes with the mAb showed that TIM was located within glycosomes, in the cytoplasm, the nucleus, and the kinetoplast. Collectively, the data shed new light on T. cruzi TIM and opens perspectives for drug design.


Assuntos
Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/imunologia , Triose-Fosfato Isomerase/imunologia , Trypanosoma cruzi/crescimento & desenvolvimento , Trypanosoma cruzi/imunologia , Animais , Doença de Chagas/imunologia , Doença de Chagas/parasitologia , Doença de Chagas/fisiopatologia , Reações Cruzadas , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Microcorpos/enzimologia , Microscopia Eletrônica , Ratos , Ratos Wistar , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Triose-Fosfato Isomerase/genética , Trypanosoma brucei brucei/enzimologia , Trypanosoma brucei brucei/ultraestrutura , Trypanosoma cruzi/enzimologia , Trypanosoma cruzi/ultraestrutura
13.
Ecotoxicol Environ Saf ; 65(2): 278-87, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16139361

RESUMO

A monospore strain of Metarhizium anisopliae var. anisopliae (EH-479/2), isolated in Mexico from Aeneolamia sp., was tested for oral acute intragastric pathogenicity and toxicity in CD-1 mice, including a thorough histological study. Animals were inoculated by gavage with one dose (10(8) conidia/animal) of viable (72 mice) and nonviable (24 mice) conidia and compared to 18 control mice. Clinical observations were done daily; mycological and histological tests were performed during necropsies at days 3, 10, 17, and 21 after the inoculation. At the end of the study, no mice showed clinical symptoms of illness, and the animals' mean weight corresponded to that of healthy adults. No inflammatory reactions were identified in analyzed organs, suggesting the nonimmunogenic status of this fungal strain. Evidence of fungal germination was noted in two lymph nodes and in liver and lung of one dead mouse, out of 72 viable-conidia treated mice. There was no evidence of toxicity symptoms in mice inoculated with nonviable conidia. The results obtained support the nonpathogenic and nontoxic status of this fungal strain when administered in a sole intragastric dose in mice.


Assuntos
Hemípteros/microbiologia , Hypocreales/patogenicidade , Micoses/microbiologia , Doença Aguda , Animais , Feminino , Hypocreales/isolamento & purificação , Fígado/microbiologia , Fígado/patologia , Pulmão/microbiologia , Pulmão/patologia , Linfonodos/microbiologia , Linfonodos/patologia , Masculino , Camundongos , Camundongos Endogâmicos , Micoses/patologia , Esporos Fúngicos/isolamento & purificação , Esporos Fúngicos/patogenicidade , Virulência
14.
Parasitology ; 132(Pt 5): 641-9, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16393367

RESUMO

PTPases have been reported as a virulence factor in different pathogens. Recent studies suggest that PTPases play a role in the pathogenesis of Leishmania infections through activation of macrophage PTPases by the parasite. We report here the presence of a membrane-bound PTPase in Leishmania major promastigotes. We detected differences in the PTPases present in the procyclic and metacyclic stages of promastigotes. In metacyclic promastigotes, the PTPase activity was totally inhibited by specific PTPase and serine/threonine inhibitors, whereas in procyclic promastigotes the PTPase activity was inhibited only with PTPase inhibitors. Two antibodies against the catalytic domains of the human placental PTPase1B and a PTPase from Trypanosoma brucei cross-reacted with a 55-60 kDa molecule present in the soluble detergent-extracted fraction of a Leishmania homogenate. Metacyclic promastigotes expressed more of this molecule than parasites in the procyclic stage. Yet the specific activity of the enzyme was lower in metacyclic than in procyclic promastigotes. Ultrastructural localization of the enzyme showed that it was more membrane-associated in metacyclic promastigotes, whereas in procyclic promastigotes it was scattered throughout the cytoplasm. This is the first demonstration of a PTPase present in Leishmania major promastigotes that differs in expression, activity and ultrastructural localization between the procyclic and metacyclic stages of the parasite's life-cycle.


Assuntos
Leishmania major/enzimologia , Leishmania major/patogenicidade , Proteínas Tirosina Fosfatases/isolamento & purificação , Proteínas de Protozoários/metabolismo , Fatores de Virulência/isolamento & purificação , Fosfatase Ácida/metabolismo , Animais , Western Blotting/métodos , Fracionamento Celular , Células Cultivadas , Citoplasma/metabolismo , Inibidores Enzimáticos/farmacologia , Leishmania major/ultraestrutura , Estágios do Ciclo de Vida/fisiologia , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/isolamento & purificação , Proteínas de Membrana/metabolismo , Microscopia Eletrônica de Transmissão/métodos , Octoxinol/química , Proteínas Tirosina Fosfatases/antagonistas & inibidores , Proteínas Tirosina Fosfatases/metabolismo , Proteínas de Protozoários/antagonistas & inibidores , Proteínas de Protozoários/isolamento & purificação , Fatores de Virulência/antagonistas & inibidores , Fatores de Virulência/metabolismo
15.
Vaccine ; 24(8): 1073-80, 2006 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-16202486

RESUMO

Influenza vaccination is a key intervention to reduce morbidity and mortality provoked by this disease. To date, the challenge of improving its efficacy remains unmet. The immunogenic synthetic peptide GK1 from Taenia crassiceps cysticerci was tested herein in its capacity as adjuvant, co-administered with the inactivated anti-influenza vaccine before and after challenge with influenza virus in both young and aged mice. Co-administration of GK1 with the influenza vaccine increased levels of anti-influenza antibodies in aged mice before and after infection, reduced the local inflammation that accompanied influenza vaccination itself and favored virus clearance after infection in both young and aged mice.


Assuntos
Adjuvantes Imunológicos/farmacologia , Vacinas contra Influenza/imunologia , Peptídeos/farmacologia , Hidróxido de Alumínio/farmacologia , Sequência de Aminoácidos , Animais , Anticorpos Antivirais/sangue , Feminino , Imunoglobulina G/sangue , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Saponinas/farmacologia , Vacinação
16.
J Anat ; 199(Pt 4): 493-7, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11693310

RESUMO

Mammalian Langerhans cells (LC) are epidermal dendritic cells which originate in bone marrow and migrate toward the T cell area of lymph nodes, where they act as professional antigen-presenting cells. A variety of cell surface markers, such as the ectoenzyme adenosine triphosphatase (ATPase), Ia and CDla antigens, have been used extensively to identify LC. Ultrastructural identification of this cell type in the mammalian epidermis is made by the demonstration of a typical and unique cytoplasmic organelle, the Birbeck granule (BG). Although we had earlier demonstrated the coexpression of ATPase and Ia antigens on epidermal dendritic cells of the chicken epidermis, the presence of the BG has not previously been documented. The aim of the present study was to investigate whether chicken epidermal LC-like cells possess an organelle similar to the BG, and thus to complete their identification. Our findings are the first demonstration of characteristic rod-shaped, racket-shaped and disc-shaped intracytoplasmic organelles, morphologically similar to the mammalian BG, in avian LC.


Assuntos
Embrião de Galinha/anatomia & histologia , Células Epidérmicas , Células de Langerhans/ultraestrutura , Animais , Citoplasma/ultraestrutura , Microscopia Eletrônica , Organelas/ultraestrutura
17.
Exp Parasitol ; 82(2): 171-81, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8617344

RESUMO

We produced a monoclonal antibody against a major cysteine proteinase of 30kDa from trophozoites of Entamoeba histolytica strain HM1:IMSS. The specificity of the monoclonal antibody was confirmed by specific inhibition of azocasein digestion and by electrophoretic analysis, in the presence of sodium dodecyl sulfate or on a substrate gel, of the antigen precipitated by the antibody. Immunofluorescent staining of trophozoites with the monoclonal antibody revealed heterogeneity in the intensity of whole cell fluorescence and subcellular localization of the stain. The latter was also observed in trophozoites, which were stained by conventional immunohistochemical methods, from experimental liver abscesses in hamsters. Ultrastructural analysis showed antigen distributed mainly in clear amorphous zones in the cytoplasm, which were not limited by a visible membrane. Proteinases are translocated from these compartments to phagocytic vacuoles after trophozoites ingest erythrocytes, suggesting that these regions might be a lysosomal equivalent of this primitive eukaryotic cell.


Assuntos
Anticorpos Monoclonais/imunologia , Cisteína Endopeptidases/análise , Entamoeba histolytica/enzimologia , Animais , Especificidade de Anticorpos , Western Blotting , Linhagem Celular , Cisteína Endopeptidases/imunologia , Entamoeba histolytica/imunologia , Imunofluorescência , Humanos , Hibridomas , Imuno-Histoquímica , Camundongos , Microscopia Imunoeletrônica , Testes de Precipitina
18.
J Anat ; 184 ( Pt 3): 591-6, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7928646

RESUMO

Langerhans cells (LC) are antigen-presenting dendritic cells located in mammalian epidermis and in other stratified epithelia. We recently demonstrated the presence of Langerhans-like cells in the epidermis of the chicken using ultrastructural histochemistry for adenosine triphosphatase (ATPase). The aim of the present study was to test whether ATPase-positive dendritic cells also express class II histocompatibility molecules (Ia antigens) encoded by the major histocompatibility complex (MHC), using a double staining technique, in separated chicken epidermal sheets. We concluded that the epidermal dendritic cells observed are the LC of the chicken, based on their morphology and spatial distribution, but mainly on the complete overlap for ATPase reaction and Ia antigen expression, these being reliable markers for the identification of mammalian LC.


Assuntos
Adenosina Trifosfatases/metabolismo , Galinhas/imunologia , Células Dendríticas/imunologia , Epiderme/imunologia , Antígenos de Histocompatibilidade Classe II/análise , Animais , Células Dendríticas/enzimologia , Feminino , Imuno-Histoquímica , Células de Langerhans/imunologia , Masculino
19.
Trop Med Int Health ; 4(12): 801-11, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10632987

RESUMO

Two patients with diffuse cutaneous leishmaniasis caused by Leishmania mexicana were treated with two leishmanicidal drugs (pentamidine and allopurinol) combined with recombinant interferon-gamma restoring Th-1 favouring conditions in the patients. Parasites decreased dramatically in the lesions and macrophages diminished concomitantly, while IL-12-producing Langerhans cells and interferon-gamma- producing NK and CD8 + lymphocytes increased in a reciprocal manner. The CD4+/CD8 + ratio in the peripheral blood normalized. During exogenous administration of interferon-gamma the parasites' capacity to inhibit the oxidative burst of the patients' monocytes was abolished. Even though Th-1-favouring conditions were restored, both patients relapsed two months after therapy was discontinued. We conclude that the tendency to develop a disease-promoting Th-2 response in DCL patients is unaffected by, and independent of, parasite numbers. Even though intensive treatment in DCL patients induced Th-1 disease restricting conditions, the disease-promoting immunomodulation of few persistent Leishmania sufficed to revert the immune response.


Assuntos
Antiprotozoários/uso terapêutico , Interferon gama/uso terapêutico , Células de Langerhans/efeitos dos fármacos , Leishmania mexicana , Leishmaniose Tegumentar Difusa/tratamento farmacológico , Leishmaniose Tegumentar Difusa/imunologia , Pentamidina/uso terapêutico , Alopurinol/uso terapêutico , Animais , Antimetabólitos/uso terapêutico , Relação CD4-CD8/efeitos dos fármacos , Quimioterapia Combinada , Humanos , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Células de Langerhans/imunologia , Células de Langerhans/parasitologia , Leishmaniose Tegumentar Difusa/patologia , Proteínas Recombinantes , Explosão Respiratória/efeitos dos fármacos , Explosão Respiratória/imunologia , Resultado do Tratamento
20.
J Anat ; 176: 1-8, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1717417

RESUMO

In mammalian epidermis a population of ATPase-positive dendritic cells, identified as Langerhans cells, has been found. Such cells are bone marrow-derived and participate in the immunological functions of the skin. We demonstrate the existence of ATPase-positive dendritic cells in separated epidermal sheets of chicken skin, by means of light and electron microscopy. They have a mean distribution of 688 +/- 265 cells/mm2 and showed several features in common with Langerhans cells. Since chickens can develop contact dermatitis, the finding is taken as the first formal demonstration of the presence of Langerhans cells in this group of vertebrates.


Assuntos
Adenosina Trifosfatases/metabolismo , Galinhas/anatomia & histologia , Células Epidérmicas , Células de Langerhans/ultraestrutura , Animais , Epiderme/enzimologia , Células de Langerhans/enzimologia , Pele/anatomia & histologia , Coloração e Rotulagem
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