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1.
J Econ Entomol ; 115(3): 706-714, 2022 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-35526117

RESUMEN

Beekeeping contributes to poverty reduction in many developing countries, and in addition, provides pollination services for sustainable crop production. In Nepal, management practices associated with beekeeping are poorly characterized, and so the potential for this sector to further contribute to livelihood development remains unclear. This study sought to examine and identify factors associated with production efficiency and financial profitability of beekeeping with the aim of enhancing economic gains for Nepali beekeepers. Our study included a sample of 150 respondents from more than twenty commercial beekeeping districts across the Terai and mountainous regions of Nepal. Profitability of beekeeping with the European honeybee (Apis mellifera) Linnaeus, 1758 (Hymenoptera: Apidae) and the Asian honeybee Apis cerana Fabricius, 1793 (Hymenoptera: Apidae) was quantified and disaggregated according to several variables, including hive-derived products produced, marketing strategy employed, number of beehives managed, and postharvest management practices. Our results showed that the different types of management practices adopted (such as number of beehives kept, colony multiplication, supplementary feeding, month of honey harvesting, and marketing approach) significantly influenced the productivity and economic profitability of beekeeping. Our results also revealed that professional supports, such as the availability of subsidies and training, were key factors to enhance productivity. As a whole, this study provides insight into the biological factors and management practices associated with higher economic returns from beekeeping. This work can help guide policymakers and professional support agencies to expand commercial beekeeping for sustainable livelihood development in Nepal and beyond.


Asunto(s)
Apicultura , Miel , Animales , Abejas , Humanos , Nepal , Polinización
2.
Braz J Med Biol Res ; 51(11): e7356, 2018 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-30304130

RESUMEN

Essential oils (EO) are volatile liquids responsible for the aroma of plants. Pterodon polygalaeflorus seeds have received widespread use in folk medicine for the treatment of inflammatory diseases. For this reason and because Pterodon polygalaeflorus seeds have great EO content, which is frequently pharmacologically active, the present study aimed to evaluate the antinociceptive effect of EO from Pterodon polygalaeflorus (EOPPgfl) and its acute toxic effects. The EEOPPgfl sample, which was extracted by steam distillation of the seeds, had a yield of 2.4% of the seeds weight and had, as major constituents, beta-elemene (48.19%), trans-caryophyllene (19.51%), and epi-bicyclosesquiphellandrene (12.24%). The EOPPgfl sample showed mild acute toxicity and its calculated median lethal dose (LD50) was 3.38 g/kg. EOPPgfl (20-60 mg/kg) showed antinociceptive activity as evidenced by several tests and inhibited writhing induced by acetic acid. The maximum effect was obtained with the 30 mg/kg dose and at 60 min after its administration. EOPPgfl also decreased formalin-induced nociception, as verified by the inhibition of the first and second phase of the formalin test. At 30 mg/kg, EOPPgfl also decreased thermally stimulated nociception. Nociception may be related to inflammatory and antiedematogenic activity and at doses ranging 10-100 mg/kg, EOPPgfl blocked dextran- and carrageenan-induced edema. The results demonstrated that EOPPgfl presented, at doses approximately 100 times smaller than LD50, an antinociceptive effect that probably was due to anti-inflammatory activities.


Asunto(s)
Analgésicos/farmacología , Fabaceae/química , Nocicepción/efectos de los fármacos , Aceites Volátiles/farmacología , Extractos Vegetales/farmacología , Aceites de Plantas/farmacología , Animales , Antiinflamatorios/farmacología , Ratones , Dimensión del Dolor , Distribución Aleatoria , Reproducibilidad de los Resultados , Semillas/química , Factores de Tiempo , Resultado del Tratamiento
3.
Braz. j. med. biol. res ; 51(11): e7356, 2018. tab, graf
Artículo en Inglés | LILACS | ID: biblio-951728

RESUMEN

Essential oils (EO) are volatile liquids responsible for the aroma of plants. Pterodon polygalaeflorus seeds have received widespread use in folk medicine for the treatment of inflammatory diseases. For this reason and because Pterodon polygalaeflorus seeds have great EO content, which is frequently pharmacologically active, the present study aimed to evaluate the antinociceptive effect of EO from Pterodon polygalaeflorus (EOPPgfl) and its acute toxic effects. The EEOPPgfl sample, which was extracted by steam distillation of the seeds, had a yield of 2.4% of the seeds weight and had, as major constituents, beta-elemene (48.19%), trans-caryophyllene (19.51%), and epi-bicyclosesquiphellandrene (12.24%). The EOPPgfl sample showed mild acute toxicity and its calculated median lethal dose (LD50) was 3.38 g/kg. EOPPgfl (20-60 mg/kg) showed antinociceptive activity as evidenced by several tests and inhibited writhing induced by acetic acid. The maximum effect was obtained with the 30 mg/kg dose and at 60 min after its administration. EOPPgfl also decreased formalin-induced nociception, as verified by the inhibition of the first and second phase of the formalin test. At 30 mg/kg, EOPPgfl also decreased thermally stimulated nociception. Nociception may be related to inflammatory and antiedematogenic activity and at doses ranging 10-100 mg/kg, EOPPgfl blocked dextran- and carrageenan-induced edema. The results demonstrated that EOPPgfl presented, at doses approximately 100 times smaller than LD50, an antinociceptive effect that probably was due to anti-inflammatory activities.


Asunto(s)
Animales , Conejos , Aceites de Plantas/farmacología , Aceites Volátiles/farmacología , Extractos Vegetales/farmacología , Nocicepción/efectos de los fármacos , Analgésicos/farmacología , Fabaceae/química , Semillas/química , Factores de Tiempo , Dimensión del Dolor , Distribución Aleatoria , Reproducibilidad de los Resultados , Resultado del Tratamiento , Antiinflamatorios/farmacología
4.
J Insect Sci ; 152015.
Artículo en Inglés | MEDLINE | ID: mdl-26518220

RESUMEN

Sexual selection predicts that individuals competing for access to sexual partners should maximize their chances of mating by looking for sites where the chances of finding partners are more likely to occur. However, males of stingless bees have been observed sharing nonspecific reproductive aggregations. This uncommon behavior appears to confer no obvious increase of individual fitness. It has been suggested that this reproductive strategy is due to the similarity between male odors common to different stingless bee species. Cuticular hydrocarbons (CHCs) are candidate odors of interest because their nonvolatile pheromone nature allows them to play an important role in sexual behavior and species recognition. Here, we review the literature to evaluate whether any phylogenetic patterns exist among male stingless bees that aggregate with closely or distantly related species. We also compared the CHC profiles of males of Neotropical stingless bee species (Plebeia sp. Schwarz, Trigona spinipes (F.), Tetragona clavipes (F.), Nannotrigona testaceicornis (Lepeletier), Scaptotrigona aff. depilis (Moure), Tetragonisca angustula (Latreille), and Melipona subnitida (Ducke) to reveal any chemical similarities among their male odors. We found males of 21 stingless bee species involved in interspecific interactions mainly from Neotropical and Indo-Malayan/Australasian regions. Alien males did not necessarily visit host aggregations of closely related species. Furthermore, the CHC profiles of different studied species were very distinct from each other and do not overlapped at all. It is unclear yet why this apparently nonadaptive behavior carried out by some stingless bee males.


Asunto(s)
Abejas/fisiología , Animales , Abejas/química , Hidrocarburos/química , Masculino , Odorantes , Feromonas/química , Filogenia , Conducta Sexual Animal , Especificidad de la Especie
5.
Braz J Med Biol Res ; 40(3): 377-81, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17334535

RESUMEN

It has been shown that mental rotation of objects and human body parts is processed differently in the human brain. But what about body parts belonging to other primates? Does our brain process this information like any other object or does it instead maximize the structural similarities with our homologous body parts? We tried to answer this question by measuring the manual reaction time (MRT) of human participants discriminating the handedness of drawings representing the hands of four anthropoid primates (orangutan, chimpanzee, gorilla, and human). Twenty-four right-handed volunteers (13 males and 11 females) were instructed to judge the handedness of a hand drawing in palm view by pressing a left/right key. The orientation of hand drawings varied from 0 masculine (fingers upwards) to 90 masculine lateral (fingers pointing away from the midline), 180 masculine (fingers downwards) and 90 masculine medial (finger towards the midline). The results showed an effect of rotation angle (F(3, 69) = 19.57, P < 0.001), but not of hand identity, on MRTs. Moreover, for all hand drawings, a medial rotation elicited shorter MRTs than a lateral rotation (960 and 1169 ms, respectively, P < 0.05). This result has been previously observed for drawings of the human hand and related to biomechanical constraints of movement performance. Our findings indicate that anthropoid hands are essentially equivalent stimuli for handedness recognition. Since the task involves mentally simulating the posture and rotation of the hands, we wondered if "mirror neurons" could be involved in establishing the motor equivalence between the stimuli and the participants' own hands.


Asunto(s)
Lateralidad Funcional/fisiología , Mano/fisiología , Tiempo de Reacción/fisiología , Reconocimiento en Psicología/fisiología , Adolescente , Adulto , Animales , Femenino , Gorilla gorilla , Humanos , Masculino , Pan troglodytes , Pongo pygmaeus , Desempeño Psicomotor/fisiología , Rotación
6.
Braz. j. med. biol. res ; 40(3): 377-381, Mar. 2007. ilus, graf
Artículo en Inglés | LILACS | ID: lil-441757

RESUMEN

It has been shown that mental rotation of objects and human body parts is processed differently in the human brain. But what about body parts belonging to other primates? Does our brain process this information like any other object or does it instead maximize the structural similarities with our homologous body parts? We tried to answer this question by measuring the manual reaction time (MRT) of human participants discriminating the handedness of drawings representing the hands of four anthropoid primates (orangutan, chimpanzee, gorilla, and human). Twenty-four right-handed volunteers (13 males and 11 females) were instructed to judge the handedness of a hand drawing in palm view by pressing a left/right key. The orientation of hand drawings varied from 0° (fingers upwards) to 90° lateral (fingers pointing away from the midline), 180° (fingers downwards) and 90° medial (finger towards the midline). The results showed an effect of rotation angle (F(3, 69) = 19.57, P < 0.001), but not of hand identity, on MRTs. Moreover, for all hand drawings, a medial rotation elicited shorter MRTs than a lateral rotation (960 and 1169 ms, respectively, P < 0.05). This result has been previously observed for drawings of the human hand and related to biomechanical constraints of movement performance. Our findings indicate that anthropoid hands are essentially equivalent stimuli for handedness recognition. Since the task involves mentally simulating the posture and rotation of the hands, we wondered if "mirror neurons" could be involved in establishing the motor equivalence between the stimuli and the participants' own hands.


Asunto(s)
Humanos , Animales , Masculino , Femenino , Adolescente , Adulto , Lateralidad Funcional/fisiología , Mano/fisiología , Rotación , Tiempo de Reacción/fisiología , Reconocimiento en Psicología/fisiología , Gorilla gorilla , Pan troglodytes , Pongo pygmaeus , Desempeño Psicomotor/fisiología
7.
J Comp Pathol ; 128(2-3): 199-202, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12634100

RESUMEN

The gross and microscopical features of a glomus tumour in the digit of a 9-year-old dog are described. The tumour consisted of a red nodule near the nail of the third digit of the right forelimb and appeared painful. The tumour cells, which had round to oval hyperchromatic nuclei and scant cytoplasm, were arranged in sheets around blood vessels, or in nests or duct-like structures. This pattern has not been described previously in canine glomus tumours. Mitotic figures were seen only occasionally. Tumour cells were strongly immunolabelled for vimentin and some expressed smooth-muscle actin and desmin. They were negative for cytokeratins, neuron-specific enolase and CD34. Silver impregnation (reticulin method) stained the reticulum around blood vessels, nests of tumour cells and duct-like structures, and a delicate reticulum was seen around each tumour cell. The morphological, immunohistochemical and histochemical patterns helped in the diagnosis of this glomus tumour.


Asunto(s)
Enfermedades de los Perros/patología , Enfermedades del Pie/veterinaria , Tumor Glómico/veterinaria , Neoplasias Cutáneas/veterinaria , Animales , Biomarcadores de Tumor/análisis , Enfermedades de los Perros/cirugía , Perros , Femenino , Enfermedades del Pie/patología , Enfermedades del Pie/cirugía , Miembro Anterior/patología , Miembro Anterior/cirugía , Tumor Glómico/química , Tumor Glómico/patología , Tumor Glómico/cirugía , Técnicas para Inmunoenzimas/veterinaria , Tinción con Nitrato de Plata/veterinaria , Neoplasias Cutáneas/química , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/cirugía , Resultado del Tratamiento , Vimentina/análisis
8.
IUBMB Life ; 49(2): 153-9, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10776600

RESUMEN

In this study, two different epitope tags (HA, c-myc) were introduced near the N terminus of the yeast PMA1 H(+)-ATPase. The resulting proteins were indistinguishable from the wild-type ATPase in their ability to travel through the secretory pathway, as judged by quantitative immunoblotting of isolated secretory vesicles. Furthermore, there were no significant abnormalities in ATPase activity (including K(m) for MgATP, Vmax, pH optimum, and IC50 for inhibition by vanadate) or in ATP-dependent proton pumping. Finally, the epitope-tagged ATPases could support normal growth and displayed the expected activation by glucose.


Asunto(s)
ATPasas de Translocación de Protón/genética , ATPasas de Translocación de Protón/metabolismo , Saccharomyces cerevisiae/enzimología , Adenosina Trifosfato/metabolismo , Secuencia de Aminoácidos , Membrana Celular/enzimología , Epítopos , Concentración de Iones de Hidrógeno , Cinética , Datos de Secuencia Molecular , Plásmidos , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , ATPasas de Translocación de Protón/química , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae/genética
9.
J Biol Chem ; 273(34): 21744-51, 1998 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-9705311

RESUMEN

Mutations at the phosphorylation site (Asp-378) of the yeast plasma-membrane H+-ATPase have been shown previously to cause misfolding of the ATPase, preventing normal movement along the secretory pathway; Asp-378 mutations also block the biogenesis of co-expressed wild-type ATPase and lead to a dominant lethal phenotype. To ask whether these defects are specific for Asp-378 or whether the phosphorylation region as a whole is involved, alanine-scanning mutagenesis has been carried out to examine the role of 11 conserved residues flanking Asp-378. In the sec6-4 expression system (Nakamoto, R. K., Rao, R., and Slayman, C. W. (1991) J. Biol. Chem. 266, 7940-7949), the mutant ATPases displayed varying abilities to reach the secretory vesicles that deliver plasma-membrane proteins to the cell surface. Indirect immunofluorescence of intact cells also gave evidence for a spectrum of behavior, ranging from mutant ATPases completely arrested (D378A, K379A, T380A, and T384A) or partially arrested in the endoplasmic reticulum to those that reached the plasma membrane in normal amounts (C376A, S377A, and G381A). Although the extent of ER retention varied among the mutants, the endoplasmic reticulum appeared to be the only secretory compartment in which the mutant ATPases accumulated. All of the mutant proteins that localized either partially or fully to the ER were also malfolded based on their abnormal sensitivity to trypsin. Among them, the severely affected mutants had a dominant lethal phenotype, and even the intermediate mutants caused a visible slowing of growth when co-expressed with wild-type ATPase. The effects on growth could be traced to the trapping of the wild-type enzyme with the mutant enzyme in the ER, as visualized by double label immunofluorescence. Taken together, the results indicate that the residues surrounding Asp-378 are critically important for ATPase maturation and transport to the cell surface.


Asunto(s)
ATPasas de Translocación de Protón/química , Secuencia de Aminoácidos , Ácido Aspártico/química , Ácido Aspártico/genética , Ácido Aspártico/metabolismo , Sitios de Unión , Membrana Celular/enzimología , Retículo Endoplásmico/enzimología , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Fosforilación , Pliegue de Proteína , ATPasas de Translocación de Protón/genética , ATPasas de Translocación de Protón/metabolismo
10.
Biochem Mol Biol Int ; 41(2): 359-66, 1997 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9063576

RESUMEN

Soluble calmodulin-binding proteins from Saccharomyces carlsbergensis were analyzed in cells grown on glucose, maltose and galactose as carbon source. A large number of polypeptide chains showed affinity for calmodulin by affinity chromatography and overlay techniques. Amongst these, polypeptides of 115, 67 and 45 kDa were only detected during the second exponential phase of growth on glucose or non-fermentative carbon sources, suggesting that they might be subjected to catabolite repression. Polypeptides of 195 and 22 kDa were only observed in cells grown on maltose, whereas 88 kDa polypeptide was only observed in galactose-grown cells. Among the calmodulin -binding polypeptides, eight were phosphorylated in a Ca2+/calmodulin -dependent manner (220, 200, 175, 100, 62, 55, 31 and 16 kDa). Ca2+/calmodulin dependent [gamma-32P] incorporation was dramatically decreased in yeast cells submitted to a heat treatment.


Asunto(s)
Proteínas de Unión a Calmodulina/aislamiento & purificación , Galactosa/metabolismo , Maltosa/metabolismo , Saccharomyces/metabolismo , Calmodulina/metabolismo , Proteínas de Unión a Calmodulina/metabolismo , Regulación Fúngica de la Expresión Génica , Glucosa/metabolismo , Calor , Fosforilación , Procesamiento Proteico-Postraduccional
11.
Braz J Med Biol Res ; 27(3): 627-36, 1994 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8081287

RESUMEN

1. Trehalase was partially purified from Escherichia coli and characterized. The Km for trehalose was 0.78 mM, the pH optimum 5.5 and the temperature optimum 30 degrees C. 2. Trehalase represented approximately 50% of the total protein released by osmotic shock. The preparation was free of nonspecific carbohydrate hydrolases, which act on sucrose, galactose and maltose, permitting trehalose determination in biological samples, such as insect hemolymph and free cell extracts among others. 3. The enzyme was stable in 50 mM maleate buffer, pH 6.2, at -8 degrees C for at least 6 months and could be used to determine trehalose in the range of 6 to 30 nmol. 4. Immobilization of the enzyme was achieved by covalent linkage to spherisorb-5NH2 (spherical silica gel). Retention of total catalytic activity averaged 32%. 5. The reactor, stored for one month at -5 degrees C, retained 98% of its initial immobilized activity. 6. This immobilized form of the enzyme could be used routinely for specific determinations of trehalose.


Asunto(s)
Enzimas Inmovilizadas/aislamiento & purificación , Escherichia coli/enzimología , Trehalasa/aislamiento & purificación , Electroforesis en Gel de Poliacrilamida/métodos , Activación Enzimática , Enzimas Inmovilizadas/metabolismo , Calor , Gel de Sílice , Dióxido de Silicio , Factores de Tiempo , Trehalasa/metabolismo , Trehalosa/análisis
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