Conservación del ombusillo, planta amenazada de la provincia de Buenos Aires, Argentina / Conserving ombusillo, an endangered plant from the province of Buenos Aires, Argentina

Phytolacca tetramera Hauman "ombusillo", es una especie vegetal endémica del SE de la Provincia de Buenos Aires, Argentina, que se halla en peligro crítico de extinción. Su principal factor de amenaza es la reducción del hábitat por acción antrópica. Esta especie presenta principios activos fungicidas y, posiblemente, dada su afinidad con otras especies del mismo género, presente compuestos antivirales, antitumorales, bactericidas e insecticidas. Se realizaron ensayos de macropropagación con distintas concentraciones de reguladores de crecimiento de tipo auxínicos que muestran claramente un enraizamiento óptimo correspondiente a segmentos de ejes aéreos vegetales “estacas” sometidas a 300 ppm de ácido indol butírico y a segmentos de tallos subterráneos sin aplicación de hormonas. Así mismo, se realizaron ensayos de germinación, en condiciones de luz y de oscuridad, comprobándose que las semillas presentan fotoblastismo positivo con un porcentaje de germinación del 65%, el cual disminuye enormemente luego del año de cosecha.

Phytolacca tetramera Hauman "ombusillo" is an endemic plant species which is in critical danger of becoming extinct; it comes from the south-east of the province of Buenos Aires. The main factor threatening this species is the reduction of its natural environment by antropic action.This species has antifungal properties and, due to its relationship with other species from the same genus, it could also have antiviral, antitumour, antibacterial and insecticidal compounds. Macropropagation experiments were carried out using different concentrations of auxinic growth regulators. Segements of aerial axis “stakes” treated with 300 ppm of indol-butiric acid and segments of underground stems without hormonal treatment provided optimum rooting. Germination experiments in dark and light conditions were also carried out, finding that seeds showed positive photoblastisme with a 65% germination rate which declined considerably after the crop had been harvested.

Type I hypersensitivity to Parthenium hysterophorus in patients with parthenium dermatitis.

BACKGROUND: Parthenium dermatitis is a major problem in urban and rural India. Patients with severe allergic rhinitis due to exposure to pollens of parthenium are reported to have parthenium specific IgE and IgG antibodies. Parthenium induces contact dermatitis by Type IV hypersensitivity and allergic rhinitis by Type-I hypersensitivity. AIMS: The study was undertaken to detect Type-I and Type-IV hypersensitivity amongst patients with parthenium dermatitis. METHODS: Fourteen patients with clinical features of parthenium dermatitis who patch tested positive to parthenium were included in the study. Patch testing was done by standard method and results interpreted as recommended by the ICDRG. Serum IgE was determined by chemiluminescence immuno assay system (CLIA). Prick testing was performed and interpreted by standard method. RESULTS: Twelve out of the 14 patients included, showed a positive prick test. Serum IgE was elevated in all patients to varying degrees (mean IgE-1279.9 IU/ml; N--up to 100 IU/ml). CONCLUSION: The positive patch test, prick test and elevated serum IgE suggest that both Type-I and Type-IV hypersensitivity may play a role in the induction and perpetuation of parthenium dermatitis in most patients. To date, delayed hypersensitivity was thought to be solely responsible for parthenium dermatitis. This study suggests that a combined type-I and type IV hypersensitivity mechanisms may be operational.

Plant immunization.

Plant immunization is the process of activating natural defense system present in plant induced by biotic or abiotic factors. Plants are pre-treated with inducing agents stimulate plant defense responses that form chemical or physical barriers that are used against the pathogen invasion. Inducers used usually give the signals to rouse the plant defense genes ultimately resulting into induced systemic resistance. In many plant-pathogen interactions, R-Avr gene interactions results in localized acquired resistance or hypersensitive response and at distal ends of plant, a broad spectrum resistance is induced known as systemic acquired resistance (SAR). Various biotic or abiotic factors induce systemic resistance in plants that is phenotypically similar to pathogen-induced systemic acquired resistance (SAR). Some of the biotic or abiotic determinants induce systemic resistance in plants through salicylic acid (SA) dependent SAR pathway, others require jasmonic acid (JA) or ethylene. Host plant remains in induced condition for a period of time, and upon challenge inoculation, resistance responses are accelerated and enhanced. Induced systemic resistance (ISR) is effective under field conditions and offers a natural mechanism for biological control of plant disease.

Neutralización del efecto hemorrágico inducido por veneno de Bothrops asper (Serpientes : Viperidae) por extractos de plantas tropicales / Neutralization of hemorrhagic effect inducid by venom of Bothrops asper (Serpentes: Viperidae) for extracts of tropical plants

Se evaluó la capacidad de extractos orgánicos de 48 especies de plantas costarricense para neutralizar la actividad hemorrágica del veneno de la serpiente Bothrops asper (terciopelo). Los extractos se evaluaron mediante un bioensayo basado en inyecciones intradérmicas de veneno en ratones, o de mezclas veneno-extracto, seguidas de la cuantificación macroscópica de la hemorragia. Se observó una inhibición total de la hemorragia con los extractos etanólicos, de acetato de etilo y acuoso de Bursera simaruba, Clusia torresii, C. palmana, Croton draco, Persea americana, Phoebe brenesii, Pimenta dioica, Sapindus saponaria, Smilax cuculmeca y Virola koschnyi. El análisis químico de estos extractos permitió identificar catequinas, flavonas, antocianinas y taninos condensados, los cuales podrían jugar un papel en la inhibición del efecto hemorrágico debido a la capacidad de quelar el ion zinc requerido por las metaloproteínas hemorrágicas para su acción

Polinosis en la región de Bahía Blanca / Pollinosis in the region of Bahía Blanca

El presente trabajo pretende mostrar una descripción actualizada de las polinosis en nuestra zona. Se efectuó el relevamiento profesional de las plantas conocidas y/o sospechadas como alergógenas en la región de Bahía Blanca. Se estudió el polen absoluto en el aire durante 3 años. Se realizó un calendario floral de 30 especies, controlando sus inflorescencias durante el mismo lapso. Fueron preparados extractos con los pólenes antecitadas y posteriormente testificados en cien pacientes afectados por polinosis. Ochenta y seis enfermos mostraron pruebas positivas a gramíneas compuestas y quenopodiáceas; sólo catorce fueron positivos a gramíneas únicamente. Los síntomas por estos últimos pólenes fueron particularmente frecuentes e intensos en el mes de noviembre, correspondiendose con la floración de aquella familia. Sin embargo, a pesar de las reacciones positivas - marcadas y frecuentes - para quenopodiáceas, las consultas durante el verano disminuyeron ostensiblemente. No fue demostrada una correlación clínica significativa entre la floración de las compuestas y la signosintomatología del grupo estudiado. Consideramos imprescindible el acabado conocimiento de la flora alergógena y su calendario floral para el diagnóstico y tratamiento de la polinosis

Nuevas fuentes de lectinas para la diferenciación entre Trypanosoma cruzi y T. rangeli / Further sources of lectins for differentiation between Trypanosoma cruzi y T. rangeli

Os extratos de 176 espécies de sementes de plantas colombianas, correspondentes a 49 famílias e 147 gêneros foram testados para detectar a presença de aglutininas frente a hemácias humanas dos grupos A+, B+, O+ e de cachorro, cavalo e coelho. Os extratos que apresentaram alguma atividade hemaglutinante, foram usados para testar a aglutinaçao de Trypanosoma cruzi e T. rangeli. Além disso, a hemolinfa de 16 espécies nativas de invertebrados foram testadas nas mesmas condiçoes. Diluiçoes seriadas dos extratos foram usadas para as aglutinaçoes. Ambas epimastigotas de T. cruzi e T. rangeli foram aglutinadas com os extratos de sete sementes de plantas diferentes e com dois tipos de hemolinfa de invertebrados. As sementes de cinco plantas aglutinaram exclusivamente as epimastigotas de T. cruzi podendo assim ser usadas para a diferenciaçao entre as formas de cultura desses tripanossomos. A secreçao do pulmao do caramujo (Bulimus sp.) lisou completamente as epimastigotas de T. cruzi mas nao afetou as formas de T. rangeli. Nao foram encontrados extratos que aglutinaram ou lisaram exclusivamente as epimastigotas de T. rangeli.

effect of Nigella sativa [black seed] on the B cell function of balb/C mice

The genus Nigella includes many species [N. sativa L., N. arensis L., N. assyriace Boiss., N. deserti Boiss., N. hispanica L., and N. damascena L., amongst which only N. sativa L. is known to be indogenous and grows well in different localities of Egypt. This species is known to have considerable therapeutic values. The immunological effect of this seed on the immune system was studied by testing the B cell function of BALB/C mice after their feeding on the seed for two weeks. The test was performed by the method of plaque assay using Cunningham and Szenberg slides. The results was so encouraging because it revealed a four fold increase in the mean number of plaques in mice fed on the seeds [80 plaques per 10 lymphocytes] while those not fed on the seeds [i.e.] control group showed only 20 plaques per 10 lymphocytes

Identification and partial purification of pollen allergens from Artemisia princeps

The pollen of Artemisia has been considered as the main late summer-autumn allergen source in this country. To identify its allergenic components, Artemisia princeps pollen extracts were separated by 10% sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE), and transferred to nitrocellulose membrane, where IgE binding components were detected by the reaction with sera of twenty Artemisia-allergic patients and 125I-anti-human IgE, sixteen components in the molecular range of 10,000 and 85,000 daltons were detected. Twelve bands bound to IgE from 50% of the sera tested, and two bands (37,000, 23,000 daltons) showed the highest (85%) frequency of IgE-binding in twenty sera tested. When the gel of SDS-PAGE with Artemisia pollen extracts was sliced into 11 allergenic groups (AG) and the protein of each AG was obtained by the gel elution method, the wormwool-RAST inhibition test showed that the AG 10 demonstrated to be the most potent, and the AG 7 was the next. Six AGs showed significant responses (more than 100% of wheal size to histamine, 1 mg/ml) on the skin prick test in more than 50% of the patients tested. It is suggested that electrophoretic transfer analysis with SDS-PAGE may be a valuable method for Artemisia allergen identification, and the possibility of partial purification of allergens by employing gel elution is discussed.

Identification and partial purification of pollen allergens from Artemisia princeps

The pollen of Artemisia has been considered as the main late summer-autumn allergen source in this country. To identify its allergenic components, Artemisia princeps pollen extracts were separated by 10% sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE), and transferred to nitrocellulose membrane, where IgE binding components were detected by the reaction with sera of twenty Artemisia-allergic patients and 125I-anti-human IgE, sixteen components in the molecular range of 10,000 and 85,000 daltons were detected. Twelve bands bound to IgE from 50% of the sera tested, and two bands (37,000, 23,000 daltons) showed the highest (85%) frequency of IgE-binding in twenty sera tested. When the gel of SDS-PAGE with Artemisia pollen extracts was sliced into 11 allergenic groups (AG) and the protein of each AG was obtained by the gel elution method, the wormwool-RAST inhibition test showed that the AG 10 demonstrated to be the most potent, and the AG 7 was the next. Six AGs showed significant responses (more than 100% of wheal size to histamine, 1 mg/ml) on the skin prick test in more than 50% of the patients tested. It is suggested that electrophoretic transfer analysis with SDS-PAGE may be a valuable method for Artemisia allergen identification, and the possibility of partial purification of allergens by employing gel elution is discussed.

An investigation on in vivo allergenicity of Artemisia annua leaves and stems.

Pollen of Artemisia annua is considered to be one of the most important allergens in autumnal hay fever in China, just as ragweed is in North America. In order to clarify the allergenicity of non-pollen containing components of the plant, Artemisia annua leaves and stems were collected and extracted before pollination time. The extracts of these pollen-free plant components were studied for allergenic activities using skin prick tests, intradermal tests, intranasal challenge and bronchial provocation tests. In 52 subjects sensitive to Artemisia pollen, 92.3% gave positive responses in skin prick tests, 100% gave positive responses in intradermal tests, 66.7% gave positive responses in intranasal challenge and 59.3% gave positive responses in bronchial provocation tests. Negative results to skin prick tests, intradermal tests and bronchial provocation tests were revealed in 30 seasonal asthmatics who gave negative responses to the pollen skin tests. Strict placebo control showed all negative tests in non-atopic adult human volunteers. We concluded that pollen-free plant extracts did have in vivo allergenic activities. Analysis of the plant allergenic components in vitro will be the subject of further studies.

One year observation of immunotherapy for Artemisia hay fever in China: a clinical and immunological study.

A controlled trial of one year immunotherapy was conducted in 50 Artemisia-sensitive hay fever patients (treatment group). From October 1985 to July 1986, all of the treatment group patients received one year regular injection of Artemisia pollen allergen extract totalling 30,000 protein nitrogen units (PNU). For these patients, symptom score indices of the posttreatment 1986 pollination season were compared with those from the pretreatment 1985 season and also with the scores of a similar group of 30 Artemisia-sensitive patients treated only with symptomatic medications during the 1986 season (control group). The 1986 symptom scores to the treatment group were significantly improved and the effective rate was 78%. Immunological study with the Human Basophil Degranulation Test (HBDT) showed a significant decrease in degranulation reactions after immunotherapy. Moreover, The decline of the HBDT positive rate in the treatment group was significantly greater in patients with improved symptoms than patients with unchanged symptoms. No difference was observed in basophil degranulation in those patients tested with a pollen-free plant extract, which was not applied in immunotherapy. The results suggested that immunotherapy could induce desensitization of basophils and that the induction might be allergen specific. Basophil desensitization may play an important role in the mechanism of immunotherapy.