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2.
J Appl Microbiol ; 111(4): 939-48, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21722279

RESUMO

AIMS: To evaluate different entomopathogenic fungal isolates against the cactus weevil Metamasius spinolae under laboratory and field conditions, and select an isolate to be used as a tool in the management of this insect pest. METHODS AND RESULTS: Four experiments were carried out. The effect of temperature on the in vitro growth of eight isolates of entomopathogenic fungi (two Metarhizium anisopliae and six Beauveria bassiana) was assessed. The susceptibility of adult M. spinolae to the same isolates was evaluated. Using three selected isolates, the interaction between susceptibility and sex of the insect was studied. Finally, a field experiment was carried out to evaluate infection of adult M. spinolae by the same three isolates under natural abiotic conditions. Overall, growth rate was greatest at 25°C for all the isolates. In vitro growth of M. anisopliae was greater than B. bassiana. Mortality of adult M. spinolae was greater when inoculated with B. bassiana compared with isolates of M. anisopliae. Susceptibility had no interaction with the sex of the insect. The proportion of insects succumbing to infection was smaller when incubated under field conditions than when incubated under laboratory conditions. CONCLUSIONS: The experiments described here showed a complex interaction between entomopathogenic fungi and M. spinolae, and these data allows us to select isolate Bb107 as a first step towards its use in the management of this pest insect. SIGNIFICANCE AND IMPACT OF THE STUDY: Our results showed that entomopathogenic fungi can be used for the control of M. spinolae, which may help reduce the use of chemical insecticides and, therefore, the exposure of Opuntia ficus-indica producers to pesticides.


Assuntos
Beauveria/patogenicidade , Cactaceae/parasitologia , Metarhizium/patogenicidade , Controle Biológico de Vetores/métodos , Gorgulhos/microbiologia , Animais , Beauveria/crescimento & desenvolvimento , Feminino , Masculino , Metarhizium/crescimento & desenvolvimento , Temperatura
3.
Rev Gastroenterol Mex ; 76(4): 322-9, 2011.
Artigo em Espanhol | MEDLINE | ID: mdl-22188957

RESUMO

INTRODUCTION: There are multiple Helicobacter pylori (Hp) detection tests, some are invasive and other noninvasive. The diagnostic accuracy of these methods varies according to the prevalence of the disease. OBJECTIVE: To determine the diagnostic accuracy of the breath test, serology and rapid urease test, considering gastric biopsy with Giemsa stain as the gold standard in Hp-infected subjects with uninvestigated dyspepsia. METHODS: Eighty four subjects (64 women, mean age 45 years) who were referred for dyspeptic symptoms were evaluated. Also, 20 healthy volunteers (12 men, average age 38 years) were evaluated. All the subjects underwent hystological analysis with Giemsa stain, breath test (Heliprobe®), rapid urease test (CLOtest®) and serological immunoassay (Hexagon®). RESULTS: Overall, Hp infection was diagnosed by histological analysis in 59 subjects (49 patients and 10 healthy subjects). Positivity to breath test, rapid urease test and serology were 56%, 46% and 44% respectively. Agreement with the histological analysis was 0.902 for the breath test, 0.620 for rapid urease test and 0.45 for serology. The area under the curve for the breath test was 0.95, for the rapid urease test was 0.82 and for serological test was 0.74. CONCLUSIONS: In our population, the breath test shown to have a diagnostic accuracy equivalent to histological analysis by Giemsa in subjects with uninvestigated dyspepsia.


Assuntos
Infecções por Helicobacter/diagnóstico , Helicobacter pylori , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Testes Respiratórios , Estudos Transversais , Dispepsia/etiologia , Feminino , Infecções por Helicobacter/complicações , Humanos , Imunoensaio , Masculino , Pessoa de Meia-Idade , Testes Sorológicos , Urease , Adulto Jovem
4.
Toxicon ; 191: 54-68, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33417946

RESUMO

The immune system can amplify or decrease the strength of its response when it is stimulated by chemical or biological substances that act as immunostimulators, immunosuppressants, or immunoadjuvants. Immunomodulation is a progressive approach to treat a diversity of pathologies with promising results, including autoimmune disorders and cancer. Animal venoms are a mixture of chemical compounds that include proteins, peptides, amines, salts, polypeptides, enzymes, among others, which produce the toxic effect. Since the discovery of captopril in the early 1980s, other components from snakes, spiders, scorpions, and marine animal venoms have been demonstrated to be useful for treating several human diseases. The valuable progress in fields such as venomics, molecular biology, biotechnology, immunology, and others has been crucial to understanding the interaction of toxins with the immune system and its application on immune pathologies. More in-depth knowledge of venoms' components and multi-disciplinary studies could facilitate their transformation into effective novel immunotherapies. This review addresses advances and research of molecules from venoms that have immunomodulatory properties.


Assuntos
Imunomodulação/fisiologia , Peçonhas/uso terapêutico , Animais , Humanos , Peptídeos , Proteínas , Escorpiões , Serpentes , Aranhas
5.
Neotrop Entomol ; 47(6): 885-891, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29368295

RESUMO

The predatory mirid bug Dicyphus hesperus Knight (Hemiptera: Miridae) is a native North America species with high potential as biological control agent of the potato psyllid, Bactericera cockerelli Sulcer (Hemiptera: Triozidae), which is a major solanaceous pest. Olfactory responses of D. hesperus to volatiles from plants infested with the potato psyllid and the effect of foraging experience on search efficacy were studied. Using a Y-tube olfactometer, we found that naïve females had no preference in choice tests between either uninfested tomato plants, or Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) eggs-infested plants, and clean air. Naïve females showed an innate positive response to B. cockerelli-infested plants, but no preference when given a choice between uninfested tomato plants and E. kuehniella eggs-infested plants. However, females with experience of foraging on B. cockerelli-infested plants showed a strong preference for B. cockerelli-infested plants (78% response) in choice tests with uninfested tomato plants and E. kuehniella eggs-infested plants. Implications of learning for augmentative biological control are discussed.


Assuntos
Comportamento Apetitivo , Hemípteros/química , Heterópteros/fisiologia , Comportamento Predatório , Compostos Orgânicos Voláteis/química , Animais , Feminino , Hemípteros/fisiologia , Herbivoria , Solanum lycopersicum
6.
J Econ Entomol ; 111(2): 549-555, 2018 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-29365143

RESUMO

Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae) and Bactericera cockerelli Sulcer (Hemiptera: Psyllidae) are important pests in tomato, and the mirid Dicyphus hesperus Knight (Heteroptera: Miridae) has been shown as an effective predator of both pests. Although the predator was able to suppress populations of both pests, the remaining levels could still exceed tolerable levels. Thus, we here hypothesized whether the combination of D. hesperus with the specialist parasitoids Eretmocerus eremicus Rose y Zolnerowich (Hymenoptera: Aphelinidae) (whitefly) and Tamarixia triozae (Burks) (Hymenoptera: Eulophidae) (psyllid) would result in better pest control on a greenhouse scale. For that, we conducted a trial in which we compared the results against B. tabaci and B. cockerelli in greenhouses treated with D. hesperus alone or the predator in combination with the specialist parasitoids. The results showed that the predator was able to establish and suppress B. tabaci and B. cockerelli in tomato, but the addition of the specialist parasitoids resulted in better and more cost-effective pest control. Implementation of this method would therefore increase the robustness and reliability of biocontrol-based integrated pest management programmes for tomato crops, over methods based exclusively on D. hesperus release.


Assuntos
Hemípteros , Interações Hospedeiro-Parasita , Controle Biológico de Vetores , Solanum lycopersicum , Vespas , Animais , Feminino , Masculino
7.
Chemosphere ; 173: 190-198, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28110008

RESUMO

2,4-Dichlorophenol (2,4-DCP) is considered a priority pollutant due to its high toxicity. Therefore, it is urgent to develop technologies for the disposal of this pollutant. Various remediation processes have been proposed for the elimination of 2,4-DCP in contaminated water, however, most of them involve high costs of operation and maintenance. This study aimed to determine the capacity of remediation of 2,4-DCP in water by Typha latifolia L. wild plants. For that, the tolerance, removal, accumulation and biotransformation of 2,4-DCP by T. latifolia were investigated. The plants were exposed to 2,4-DCP solutions with a concentration range from 1.5 to 300 mgL-1 for 10 days. They exhibited a reduction in chlorophyll levels and growth rate when 2,4-DCP solutions were ≥30 mgL-1 and ≥50 mgL-1, respectively. The removal of contaminant was dose-depended, being 99.7% at 1.5-3 mgL-1, 59-70% at 10-70 mgL-1 and 35-42% at 100-300 mgL-1 of 2,4-DCP in the solution. Studies indicated that 2,4-DCP was mainly accumulated in root tissue rather than in shoot tissue. Acid hydrolysis of biomass extracts suggests 2,4-DCP bioconjugates formation in root tissue as a response mechanism. Additionally, an increment in glutathione S-transferase (GST) activity could indicate a 2,4-DCP conjugation with glutathione as a detoxification mechanism of T. latifolia.


Assuntos
Biodegradação Ambiental/efeitos dos fármacos , Biotransformação/efeitos dos fármacos , Clorofenóis/toxicidade , Tolerância a Medicamentos , Recuperação e Remediação Ambiental/métodos , Raízes de Plantas/metabolismo , Typhaceae/metabolismo , Anti-Helmínticos/isolamento & purificação , Anti-Helmínticos/toxicidade , Clorofenóis/isolamento & purificação , Glutationa Transferase/metabolismo , Poluentes Químicos da Água
8.
Neotrop Entomol ; 45(1): 80-7, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26438409

RESUMO

Spittlebugs from the genus Aeneolamia are important pests of sugarcane. Although the use of the entomopathogenic fungus Metarhizum anisopliae s.l. for control of this pest is becoming more common in Mexico, fundamental information regarding M. anisopliae in sugarcane plantations is practically non-existent. Using phylogenetic analysis, we determined the specific diversity of Metarhizium spp. infecting adult spittlebugs in sugarcane plantations from four Mexican states. We obtained 29 isolates of M. anisopliae s.str. Haplotype network analysis revealed the existence of eight haplotypes. Eight selected isolates, representing the four Mexican states, were grown at different temperatures in vitro; isolates from Oaxaca achieved the greatest growth followed by isolates from Veracruz, San Luis Potosi and Tabasco. No relationship was found between in vitro growth and haplotype diversity. Our results represent a significant contribution to the better understanding of the ecology of Metarhizum spp. in the sugarcane agroecosystem.


Assuntos
Hemípteros/microbiologia , Metarhizium/classificação , Controle Biológico de Vetores , Filogenia , Saccharum , Animais , Metarhizium/patogenicidade , México
9.
Photochem Photobiol ; 54(3): 329-33, 1991 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1784633

RESUMO

The photolysis of para-methyl and para-thiomethylphenylazide at 77 K produces the corresponding triplet nitrenes which can be detected by electron paramagnetic resonance (EPR) spectroscopy. Photolysis of these azides in frozen toluene at 77 K leads to insertion of the nitrene into a benzylic C-H bond of the matrix in modest yields. Photolysis of iodinated aryl azides under these conditions does not produce triplet nitrenes that can be detected by EPR spectroscopy. In contrast to the para-methyl and para-thiomethyl substituted phenyl nitrenes, photo-induced coupling of iodo-substituted phenyl nitrenes to toluene proceeds in very poor yield.


Assuntos
Azidas/química , Derivados de Benzeno/química , Cristalização , Congelamento , Fotólise , Relação Estrutura-Atividade , Tolueno
10.
Ginecol Obstet Mex ; 69: 151-4, 2001 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-11452413

RESUMO

It's a report of a case of abdominal pregnancy of 36.3 weeks, at Hospital General de México and obtained a male newborn child, weight 1.920 grammes, Apgar 2/5/7 and Capurro of 36.3 weeks. Statistics, clinical manifestations and management are described.


Assuntos
Resultado da Gravidez , Gravidez Ectópica/diagnóstico por imagem , Abdome , Adulto , Feminino , Humanos , Gravidez , Ultrassonografia
11.
Acta Otorrinolaringol Esp ; 55(3): 114-9, 2004 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-15253337

RESUMO

From the 80's and facing the different approaches available to asses which one offered more benefits between all of them, the surgery to the demand has its place. The objective of this work is to determine the audio-surgical results in the patients with aticomastoidectomy to demand with reconstruction of later wall or stuffing of the mastoid cavity, and to show the results three years later. A prospective and descriptive study in 22 patients who underwent a mastoidectomy to demand using outologous cartilage for the reconstruction of the later wall, and bone powder obtained from the surgical drilling to fill up the mastoid cavity.


Assuntos
Processo Mastoide/cirurgia , Mastoidite/cirurgia , Adolescente , Procedimentos Cirúrgicos Eletivos , Humanos , Estudos Prospectivos , Procedimentos de Cirurgia Plástica
15.
Bioconjug Chem ; 4(2): 172-7, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-7873649

RESUMO

A series of fluorinated aryl azides and fluorinated azidobenzoates were studied by laser flash photolysis techniques. Using the pyridine ylide probe method it was possible to determine whether a singlet nitrene or ring-expanded ketenimine ylide is the trappable intermediate that is generated at ambient temperature. It was determined that two fluorine substituents, ortho and ortho' substituted relative to the azide group, are required to retard ring expansion and allow bimolecular capture of the singlet nitrene. LFP of ortho, ortho' difluorinated aryl azides in methanol produces the ground triplet state of the nitrene. The results are consistent with chemical analysis of reaction mixtures. The implications of this data for the design of photoaffinity labeling reagents are discussed.


Assuntos
Marcadores de Afinidade/síntese química , Azidas/química , Desenho de Fármacos , Flúor , Lasers , Benzeno , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Metanol , Fotólise , Piridinas , Análise Espectral
16.
Pract Odontol ; 9(7): 18-20, 1988 Jul.
Artigo em Espanhol | MEDLINE | ID: mdl-3272407

RESUMO

It has been suggested that among American Indians, as in some genetically-related Asiatic ethnic groups, incidence of cleft lip and/or cleft palate is higher than among people of Caucasian extraction. Such hypothesis, plus growing demand for services observed at a center for the surgery of cleft lip and cleft palate in Campeche state, led the authors to undertake research among the Maya residents of that region. However, neither careful review of case histories nor field research performed in several Indian communities could confirm the hypothesis of a higher incidence among this ethnic community.


Assuntos
Fenda Labial/epidemiologia , Fissura Palatina/epidemiologia , Humanos , Indígenas Norte-Americanos , México/epidemiologia
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