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1.
J Anim Physiol Anim Nutr (Berl) ; 91(5-6): 282-8, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17516953

RESUMEN

Although knowledge of the nutrient requirements of pet birds has increased a lot over the last few years, basic data on food and water intake and the energy requirements of nectarivorous species, such as lorikeets, are scarce. Thus, the aim of this study was to try to generate some of these data for lorikeets kept at maintenance. Determination of the daily maintenance energy requirement enables calculation of the daily ration and thus, the appropriate nutrient concentrations in order to maintain body weight. Investigations were carried out with six Goldie's lorikeets (GL; Trichoglossus goldiei: 40-50 g BW; 1-4 years) and six rainbow lorikeets (RL; Trichoglossus haematodus haematodus: 120-140 g BW; 1-12 years). Three of the most commonly used diets/foods (commercial 'lory soup'/apples/pollen: crude ash - 52.9/17.8/18.8; crude protein - 178/32.5/191; crude fat - 52.8/0.89/73.1; crude fibre - 17.9/40.5/30.4; starch - 139/not detectable/127; sugar - 522/859/418 g/kg DM; ME - 13.9/14.6/10.9 MJ/kg DM) were individually offered ad libitum. The measured dry matter (DM) intake (g/100 g BW) corresponded well to the values reported for granivorous bird species of similar body mass. Both lorikeet species achieved an apparent digestibility of organic matter of more than 90% for apples, approximately 82% for 'lory soup' and approximately 55% for pollen. The water content of the food affected the DM content of the excreta; 8% when fed 'lory soup', 2% for apples and approximately 30% when fed pollen. Regression analysis of body weight change relative to energy intake demonstrated constant body mass (assuming no change in body composition) when the daily energy intakes were 860 (GL) or 650 (RL) kJ ME/kg BW(0.75).


Asunto(s)
Digestión , Ingestión de Energía/fisiología , Metabolismo Energético/fisiología , Necesidades Nutricionales , Loros , Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Composición Corporal/fisiología , Peso Corporal/fisiología , Loros/metabolismo
2.
J Neural Transm (Vienna) ; 114(11): 1395-406, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17510731

RESUMEN

Stem and progenitor cells provide a promising therapeutic strategy for amyotrophic lateral sclerosis (ALS). To comparatively evaluate the therapeutic potentials of human bone marrow-derived mesodermal stromal cells (hMSCs) and umbilical cord blood cells (hUBCs) in ALS, we transplanted hMSCs and hUBCs and their neuroectodermal derivatives (hMSC-NSCs and hUBC-NSCs) into the ALS mouse model over-expressing the G93A mutant of the human SOD1 gene. We used a standardized protocol similar to clinical studies by performing a power calculation to estimate sample size prior to transplantation, matching the treatment groups for gender and hSOD-G93A gene content, and applying a novel method for directly injecting 100,000 cells into the CSF (the cisterna magna). Ten days after transplantation we found many cells within the subarachnoidal space ranging from frontal basal cisterns back to the cisterna magna, but only a few cells around the spinal cord. hMSCs and hMSC-NSCs were also located within the Purkinje cell layer. Intrathecal cell application did not affect survival times of mice compared to controls. Consistently, time of disease onset and first pareses, death weight, and motor neuron count in lumbar spinal cord did not vary between treatment groups. Interestingly, transplantation of hMSCs led to an increase of pre-symptomatic motor performance compared to controls in female animals. The negative outcome of the present study is most likely due to insufficient cell numbers within the affected brain regions (mainly the spinal cord). Further experiments defining the optimal cell dose, time point and route of application and particularly strategies to improve the homing of transplanted cells towards the CNS region of interest are warranted to define the therapeutic potential of mesodermal stem cells for the treatment of ALS.


Asunto(s)
Esclerosis Amiotrófica Lateral/terapia , Movimiento Celular/fisiología , Columna Vertebral/fisiología , Trasplante de Células Madre , Envejecimiento/fisiología , Esclerosis Amiotrófica Lateral/genética , Esclerosis Amiotrófica Lateral/fisiopatología , Animales , Recuento de Células , Supervivencia Celular , Cisterna Magna/fisiología , Progresión de la Enfermedad , Humanos , Ratones , Ratones Transgénicos , Desempeño Psicomotor/fisiología , Tamaño de la Muestra , Espacio Subaracnoideo/fisiología , Superóxido Dismutasa/genética
3.
J Neurosci Res ; 84(5): 993-1002, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16878319

RESUMEN

The effect of dominant-negative regulator of basic helix-loop-helix (bHLH) transcription factors, an ID1 protein, on growth and differentiation of neural stem-like cell line derived from human umbilical cord blood (HUCB-NSC) was investigated. This nontransformed, mesodermal germ layer-originated line contains high levels of ID1 protein, whose intercellular distribution reflects HUCB-NSC differentiation status. Whereas cells remained undifferentiated and self-renewing in serum-free (SF) cultures, ID1 protein, although highly expressed, did not attain cell nuclei and was localized mainly in cytoplasm. In long-term-expanded cultures of partially committed (primed) HUCB-NSC grown in a low serum concentration (LS cultures) ID1 protein became translocated toward cell nuclei. Further neuronal differentiation of the cells, either spontaneous in the presence of serum or induced by neuromorphogens (dBcAMP, RA), resulted in almost complete depletion of ID1 mRNA and protein. Accordingly, HUCB-NSC transfectants overexpressing the ID1 gene were significantly inhibited in their differentiation. Notably, only neuronal and not glial development was affected after ID1 overexpression. A similar gain-of-function effect of ID1 transfection was observed in human NSC-like line (DEV) of medullobastoma origin, which is constitutively devoid of ID1 expression. Thus, our results on HUCB-NSC confirm further its neural-specific behavior and the crucial role of ID1 protein as a potent negative regulator of neural stem cell differentiation, pointing out that this protein distribution between cytoplasmic and nuclear cell compartments can be one of the most important steps in differentiation signal transduction.


Asunto(s)
Sangre Fetal/citología , Proteína 1 Inhibidora de la Diferenciación/fisiología , Neuronas/fisiología , Células Madre/fisiología , Análisis de Varianza , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/fisiología , Línea Celular , Expresión Génica/efectos de los fármacos , Expresión Génica/fisiología , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Inmunohistoquímica/métodos , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Neuronas/efectos de los fármacos , ARN Mensajero/biosíntesis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Células Madre/efectos de los fármacos , Transfección/métodos
4.
J Neurosci Res ; 83(4): 627-37, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16435396

RESUMEN

In vitro studies conducted by our research group documented that neural progenitor cells can be selected from human umbilical cord blood (HUCB-NPs). Due to further expansion of these cells we have established the first human umbilical cord blood-derived neural-like stem cell line (HUCB-NSC) growing in serum-free (SF) or low-serum (LS) medium for over 3 years. The purpose of the study was to evaluate the neurogenic potential of HUCB-NSCs cultured in SF and LS condition in different in vitro settings before transplantation. We have shown that the number of cells attaining neuronal features was significantly higher for cultures expanded in LS than in SF condition. Moreover, the presence of neuromorphogens, cultured rat astrocytes or hippocampal slices promoted further differentiation of HUCB-NSCs into neural lineage much more effectively when the cells had derived from LS cultures. The highest response was observed in the case of co-cultures with rat primary astrocytes as well as hippocampal organotypic slices. However, the LS cells co-cultured with hippocampal slices expressed exclusively a set of early and late neuronal markers whereas no detection of cells with glial-specific markers was possible. In conclusion, certain level of stem/progenitor cell commitment is important for optimal response of HUCB-NSC on the neurogenic signals provided by surrounding environment in vitro.


Asunto(s)
Sangre Fetal/fisiología , Neuronas/fisiología , Células Madre/fisiología , Animales , Astrocitos/fisiología , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Recuento de Células , Células Cultivadas , Medios de Cultivo , Proteínas de Unión al ADN/genética , Proteína Ácida Fibrilar de la Glía/genética , Proteínas HMGB/genética , Hipocampo/citología , Hipocampo/fisiología , Humanos , Inmunohistoquímica , Técnicas In Vitro , Proteínas Asociadas a Microtúbulos/genética , Factor 3 de Transcripción de Unión a Octámeros/genética , Factores de Transcripción Otx/genética , Fenotipo , Ratas , Ratas Wistar , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Transcripción SOXB1 , Factores de Transcripción/genética , Transfección
5.
Toxicol In Vitro ; 19(7): 991-9, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16084685

RESUMEN

Neural stem cell line developed from human umbilical cord blood (HUCB-NSC) [Buzanska et al., 2003. Journal of Neurochemistry 85, 33] is an ethically uncontroversial source of stem cells, able to differentiate into neuronal, astrocytic and oligodendroglial lineages. Developmental fate decisions of HUCB-NSC can be experimentally manipulated in vitro by the presence of trophic factors, mitogenes and neuromorphogenes, but can also be influenced by neurotoxins. In this report two-dimensional (2-D) and three-dimensional (3-D) HUCB-NSC cultures are introduced as useful models for testing developmental neurotoxicity. For 2-D culture models we established a standardized method for the assessment of the growth rate and cell differentiation in 96-well plates. The proliferative capacity of the HUCB-NSC was monitored by the MTT test while their ability to differentiate into neural-like cells by immunocytochemistry of beta-tubulin III and MAP-2 for neurons, GFAP and S-100beta for astrocytes and GalC for oligodendrocytes. The 3-D culture of HUCB-NSC is represented by neurospheres. Proliferation and migration of the intermediate precursors from attached neurospheres are shown to be controlled and altered by various growth factors and further modulated by the extracellular matrix component-fibronectin. Thus, neurospheres derived from the HUCB-NSC line can represent a suitable model of the activation of dormant stem cells residing in their niche, and can be used for neurotoxic studies.


Asunto(s)
Fármacos del Sistema Nervioso Central/toxicidad , Células Madre Pluripotentes/efectos de los fármacos , Astrocitos/efectos de los fármacos , Adhesión Celular/efectos de los fármacos , Técnicas de Cultivo de Célula , Diferenciación Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Sangre Fetal , Fibronectinas/farmacología , Proteína Ácida Fibrilar de la Glía/análisis , Sustancias de Crecimiento/farmacología , Humanos , Proteínas Asociadas a Microtúbulos/análisis , Neuronas/efectos de los fármacos , Oligodendroglía/efectos de los fármacos , Esferoides Celulares/efectos de los fármacos , Pruebas de Toxicidad , Tubulina (Proteína)/análisis
6.
J Chem Ecol ; 11(8): 1093-113, 1985 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24310333

RESUMEN

The defensive osmeterial secretion of pre-final instar larvae of the citrus swallowtail,Papilio demodocus (Lepidoptera: Papilionidae) was found to contain methyl 3-hydroxybutanoate, 3-hydroxybutanoic acid, α-pinene, myrcene, limonene, ß-phellandrene, (Z)-ocimene, (E)-ocimene, ß-caryophyllene, (E)-ß-farnesene, and germacrene-A, as well as a further number of unidentified sesquiterpenoid constituents. The presence of germacrene-A in the secretion was inferred from the formation of ß-elemene under certain GC conditions. Larvae of the second, third, and fourth instars produce qualitatively similar secretions. Remarkable quantitative differences were found between the secretions of individual larvae. These variations could not be correlated with the diet on which the larvae were fed, their sex, instar, or color form. However, in a number of larvae the two prongs of the osmeterium were found to produce quantitatively different secretions.

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