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1.
Insects ; 14(7)2023 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-37504594

RESUMEN

The house cricket, Acheta domesticus, is a commonly reared insect for food and feed purposes. In 1977, a report described a colony collapse, which was caused by the single-stranded DNA virus Acheta domesticus densovirus (AdDV). Currently, there are no confirmed A. domesticus colonies free of AdDV, and viral disease outbreaks are a continuous threat to A. domesticus mass rearing. Correlations between cricket rearing density or temperature and AdDV abundance have been hypothesized, but experimental evidence is lacking. Optimised rearing conditions, including temperature and density, are key to cost-effective cricket production. In this study, house crickets were subjected to different combinations of rearing density (10, 20, 40 crickets per box) and temperature (25, 30, 35 °C) to study the effect on cricket survival, biomass, and AdDV abundance. Rearing temperature affected had a minor effect on survival, which ranged between 80 and 83%. Total cricket biomass increased with higher temperatures and higher densities. Viral abundance in crickets at the end of the rearing period was variable; however, high rearing density seemed to result in higher AdDV abundance. At 35 °C, a temperature considered suboptimal for house cricket production, viral abundance tended to be lower than at 25 or 30 °C.

2.
Psychopharmacology (Berl) ; 213(2-3): 377-91, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21052985

RESUMEN

RATIONALE: 3,4-Methylenedioxymethamphetamine (MDMA, "ecstasy") is a widely used recreational drug known to cause selective long-term serotonergic damage. OBJECTIVES: The aim of this study was to characterize the ultrastructure of serotonergic pericarya and proximal neurites in the dorsal raphe nucleus as well as the ultrastructure of serotonergic axons in the frontal cortex of adolescent Dark Agouti rats 3 days after treatment with 15 mg/kg i.p. MDMA. METHODS: Light microscopic immunohistochemistry and pre-embedding immunoelectron microscopy with a novel tryptophan hydroxylase-2 (Tph2) specific antibody, as a marker of serotonergic structures. RESULTS: Light microscopic analysis showed reduced serotonergic axon density and aberrant swollen varicosities in the frontal cortex of MDMA-treated animals. According to the electron microscopic analysis, Tph2 exhibited diffuse cytoplasmic immunolocalization in dorsal raphe neuronal cell bodies. The ultrastructural-morphometric analysis of these cell bodies did not indicate pathological changes or significant alteration in the cross-sectional areal density of any examined organelles. Proximal serotonergic neurites in the dorsal raphe exhibited no ultrastructural alteration. However, in the frontal cortex among intact fibers, numerous serotonergic axons with destructed microtubules were found. Most of their mitochondria were intact, albeit some injured axons also contained degenerating mitochondria; moreover, a few of them comprised confluent membrane whorls only. CONCLUSIONS: Our treatment protocol does not lead to ultrastructural alteration in the serotonergic dorsal raphe cell bodies and in their proximal neurites but causes impairment in cortical serotonergic axons. In these, the main ultrastructural alteration is the destruction of microtubules although a smaller portion of these axons probably undergo an irreversible damage.


Asunto(s)
N-Metil-3,4-metilenodioxianfetamina/toxicidad , Serotoninérgicos/toxicidad , Serotonina/metabolismo , Triptófano Hidroxilasa/metabolismo , Animales , Axones/efectos de los fármacos , Axones/metabolismo , Lóbulo Frontal/efectos de los fármacos , Lóbulo Frontal/metabolismo , Lóbulo Frontal/ultraestructura , Masculino , Microscopía Electrónica , Microscopía Inmunoelectrónica , Neuritas/efectos de los fármacos , Neuritas/metabolismo , Núcleos del Rafe/efectos de los fármacos , Núcleos del Rafe/metabolismo , Núcleos del Rafe/ultraestructura , Ratas
3.
Int J Dev Neurosci ; 26(7): 713-21, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18678240

RESUMEN

Cerebral dysgeneses are in the background of several neurological and mental disturbances. The aim of the present study was to investigate structural and activity changes following disturbed postnatal neuronal development in mice. Newborn C57Bl6 mice were exposed to 5-bromo-2'-deoxyuridine (BrdU: daily 50 microg/g body weight) during a period between postnatal days P0-P5 or P0-P11, respectively, and neuronal malformation and malfunctioning of somatosensory (barrel field) cortex was analyzed in adolescent animals. Alterations in histological architecture of interneuronal and glial elements were studied and correlated with electrophysiological modifications. Between P30 and P35 days litters underwent ex vivo electrophysiological experiments to examine the changes in basic excitability and in synaptic efficacy. Parallel immunohistochemistry was performed to detect BrdU, GABA and GFAP. There were no BrdU immunopositive cell nuclei in control animals, but marked staining was observed in both BrdU treated groups. Lessening in the number of GABAergic neurons was observed in the treated groups. GFAP immunohistochemical analysis has shown an increased number of activated astroglial cells in treated animals. Reduction of the number of GABAergic neurons was observed in the treated groups. Electrophysiological recordings on cortical slices showed increased excitability in the treated groups.


Asunto(s)
Bromodesoxiuridina/toxicidad , Corteza Somatosensorial/crecimiento & desarrollo , Potenciales de Acción/fisiología , Envejecimiento/fisiología , Animales , Animales Recién Nacidos , Antimetabolitos/toxicidad , Biomarcadores/metabolismo , Femenino , Proteína Ácida Fibrilar de la Glía/metabolismo , Gliosis/patología , Gliosis/fisiopatología , Inmunohistoquímica , Interneuronas/efectos de los fármacos , Interneuronas/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Neuroglía/efectos de los fármacos , Neuroglía/patología , Corteza Somatosensorial/efectos de los fármacos , Corteza Somatosensorial/fisiopatología , Trastornos Somatosensoriales/inducido químicamente , Trastornos Somatosensoriales/patología , Trastornos Somatosensoriales/fisiopatología , Transmisión Sináptica/efectos de los fármacos , Transmisión Sináptica/fisiología , Ácido gamma-Aminobutírico/metabolismo
4.
J Chromatogr A ; 1181(1-2): 103-15, 2008 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-18201710

RESUMEN

Programmed temperature retention indices (PTRIs) calculated according to the equations of Van den Dool and Kratz, Golovnya and Uraletz, and Erdey et al. (also referred to as Antoine's integrated equation) are used in this work. Precalculation of isotherm retention indices from the results of a linearly programmed temperature GC is also presented. Deviations between experimental and calculated isothermal retention indices are below 2 retention index units. A relative "volatility" retention index is defined, as a function of the "volatilities"of the solute and the bracket reference n-alkanes. The comparison of the "volatility" retention indices with the PTRIs obtained with the other above equations shows absolute deviations of up to 4 retention index units. Based on an earlier "equivalent" temperature concept and on Tekler's proviso, a novel way for the utilization of Sadtler's retention index database, which takes advantage of the 3 data supplied by the library, is proposed.


Asunto(s)
Cromatografía de Gases/métodos , Alcanos/aislamiento & purificación , Derivados del Benceno/aislamiento & purificación , Modelos Teóricos , Octanos/aislamiento & purificación , Programas Informáticos , Temperatura
5.
Ideggyogy Sz ; 60(3-4): 144-7, 2007 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-17451056

RESUMEN

We have investigated the spatio-temporal expression pattern of doublecortin (DCX) protein from postnatal day (P) 2 to postnatal day (P) 22 in the brain of developing mouse. We compared the expression of DCX in the rostral migratory stream (RMS) and dentate gyrus of the hippocampus (DG). Weak expression of DCX was detected in the RMS at P5, it became gradually stronger during the second postnatal week and reached its strongest expression by P18-P22. Moderate DCX immunostaining was present in the DG at P11, its marked expression--characteristic of newly generated neurons in the adult DG -appeared only after P22. Morphological and functional maturation was different in the RMS and DG, continuous neurogenesis appeared earlier in the RMS than in the DG.


Asunto(s)
Envejecimiento/metabolismo , Hipocampo/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Neuropéptidos/metabolismo , Animales , Movimiento Celular , Giro Dentado/metabolismo , Proteínas de Dominio Doblecortina , Proteína Doblecortina , Regulación del Desarrollo de la Expresión Génica , Hipocampo/crecimiento & desarrollo , Inmunohistoquímica , Ratones , Ratones Endogámicos C57BL , Factores de Tiempo
6.
Diabetes Metab Res Rev ; 23(4): 276-85, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17103487

RESUMEN

BACKGROUND: Aim of this trial was to test whether heat shock protein peptide DiaPep277 treatment in adult and paediatric patients with recent-onset type 1 diabetes (T1D) is safe and whether it can preserve endogenous insulin production. METHODS: Two studies were performed in a prospective, multicentre, double-blind, placebo-controlled trial. Fifty adult (study p520, aged 16-44 years) and 49 paediatric patients (study p521, 4-15 years) with recent-onset T1D were treated subcutaneously at four different time points with 0.2 mg or 1.0 mg DiaPep277 versus placebo and followed for 18 months. Adult patients were treated with 0.2 mg, 1.0 mg or 2.5 mg DiaPep277 versus placebo. Stimulated C-peptide served as readout for functional beta-cell-mass. RESULTS: DiaPep277-treatment was not associated with severe side effects. No differences were found in placebo and DiaPep277 treated groups. In adults, a modest trend towards better maintenance of beta-cell function was observed in the 0.2 mg and 1.0 mg group, while there was significant loss of stimulated C-peptide in the placebo and 2.5 mg group. Paediatric patients with low HLA risk showed stable C-peptide levels until 13 months upon treatment with 1 mg DiaPep277. Despite similar stimulated C-peptide levels at baseline, children exhibited a more pronounced loss of beta-cell function over 18 months than adults (p = 0.0003). CONCLUSION: Administration of DiaPep277 seems safe and may have beneficial effects on C-peptide levels over time in some patients with T1D, but this finding was not accompanied by reduced HbA1c or insulin requirement. Studies with more patients and longer follow-up are needed to further study the effect of DiaPep277.


Asunto(s)
Diabetes Mellitus Tipo 1/tratamiento farmacológico , Células Secretoras de Insulina/efectos de los fármacos , Células Secretoras de Insulina/metabolismo , Péptidos/uso terapéutico , Adolescente , Adulto , Autoanticuerpos/sangre , Péptido C/sangre , Chaperonina 60 , Niño , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/patología , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Quimioterapia Combinada , Hemoglobina Glucada/metabolismo , Antígenos HLA/sangre , Antígenos HLA/clasificación , Humanos , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/uso terapéutico , Inyecciones Subcutáneas , Insulina/administración & dosificación , Insulina/uso terapéutico , Células Secretoras de Insulina/patología , Islotes Pancreáticos/inmunología , Fragmentos de Péptidos , Péptidos/administración & dosificación , Péptidos/efectos adversos
7.
Regul Pept ; 123(1-3): 209-16, 2004 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-15518914

RESUMEN

For the first time, the relationship between secretin and autism has been demonstrated by one of us. Intravenous administration of secretin in autistic children caused a fivefold higher pancreaticobiliary fluid secretion than in healthy ones and, at least in some of the patients, better mental functions were reported after the secretin test. Because the precise localization of secretin in the brain is still not completely known, the abovementioned observation led us to map secretin immunoreactivity in the nervous system of several mammalian species. In the present work, the distribution of secretin immunoreactivity in cat and human nervous systems was compared with that of rats using an immunohistochemical approach. Secretin immunoreactivity was observed in the following brain structures of both humans and in colchicine-treated rats: (1) Purkinje cells in the cerebellar cortex; (2) central cerebellar nuclei; (3) pyramidal cells in the motor cortex; and (4) primary sensory neurons. Additionally, secretin immnoreactive cells were observed in the human hippocampus and amygdala and in third-order sensory neurons of the rat auditory system. In cats, secretin was only observed in the spinal ganglia. Our findings support the view that secretin is not only a gastrointestinal peptide but that it is also a neuropeptide. Its presence or the lack of its presence may have a role in the development of behavioral disorders.


Asunto(s)
Trastorno Autístico/etiología , Trastorno Autístico/metabolismo , Sistema Nervioso/metabolismo , Secretina/metabolismo , Animales , Tronco Encefálico/metabolismo , Gatos , Cerebelo/metabolismo , Corteza Cerebral/metabolismo , Ganglios Sensoriales/metabolismo , Humanos , Inmunohistoquímica , Sistema Límbico/metabolismo , Masculino , Ratas , Ratas Sprague-Dawley , Especificidad de la Especie , Distribución Tisular
8.
Anal Bioanal Chem ; 376(5): 735-44, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12819849

RESUMEN

Infinite-dilution gas-liquid chromatographic activity coefficients at 393.15 K (with their thermal and athermal components) and derived excess partial molar Gibbs energies, enthalpies, and entropies have been determined for each of 33 solutes of different polarity on four stationary phases with cyano groups, using retention data taken from the literature. The strongest interactions predicted by the solvation model are the dipolarity/polarizability, the acidic solute-basic stationary phase interaction, and nonpolar cavity formation and dispersion. These interactions were compared with those evaluated from the solute activity coefficients; the effect of the solute connectivity index and dipole moment on nonpolar and polar interactions, respectively, is discussed. The dependence of the thermal activity coefficient on nonpolar interactions, and the influence of stationary phase polarity on the four solute-stationary phase interactions, were evaluated. The nonpolar interaction increases with increasing connectivity and with increasing athermal activity coefficient. The dipolarity/polarizability interaction increases with increasing solute dipole moment. Finally, polar interactions increase with increasing stationary phase polarity whereas the nonpolar interaction is independent of stationary phase polarity.

9.
J Neurocytol ; 32(3): 217-27, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-14724385

RESUMEN

The Lugaro cell is a feedback interneuron of the cerebellar cortex, recognizable by its characteristic morphology. Postnatal neuronal migration to the cortex has been described for several cerebellar interneurons. Since in our previous studies we observed Lugaro-like cells (LCs) in the white matter (WM) and internal granular layer (IGL) of the cerebellum of young cats, we assumed that a proportion of these cells migrate also postnatally to their destination. In the present study using and immunostaining for the metabotropic glutamate receptor mGluR1alpha and neurofilament protein SMI 311 the number and spatial distribution of LCs at different postnatal days were investigated. We found that the number and distribution of both mGluR1a-immunoreactive (ir) and of SMI 311-ir LCs changed with age in the developing cerebellar cortex of kittens: developing LCs express mGluR1alpha already in the newborn, while expression of SMI 311-ir in LCs appears only about a week later. At postnatal day 1 (P1) relatively few mGluR1-ir LCs were detected in the WM and at the border of WM and IGL. Later, their number increased sharply until P15 (6-7 fold) and decreased continuously between P15 and P135. SMI 311-ir LCs were not present at P1 and even at P8 only a few were observed in the WM or in infraganglionic positions. Their number increased gradually (12-14 fold) until adulthood when their number was stabilized at 8.000-10.000/cerebellum. At the same time the number of probably ectopic SMI 311-ir LCs decreased with age: at P22 about one third of them was found in "ectopic" position, whereas in the adult cat only about 10-12% of LCs's was either in the WM or scattered in the whole depth of the granular layer. These results suggest that: (1) most LCs appear in the cerebellar cortex postnatally; and (2) postnatal migration and incorporation of LCs to the cortex is a much longer process than previously expected, occurring even after the cytoarchitectonic built-up (about P65-P70 in cat) of the cerebellum.


Asunto(s)
Antígenos de Diferenciación/metabolismo , Corteza Cerebelosa/metabolismo , Interneuronas/metabolismo , Proteínas de Neurofilamentos/metabolismo , Receptores de Glutamato Metabotrópico/metabolismo , Envejecimiento/metabolismo , Animales , Animales Recién Nacidos , Anticuerpos Monoclonales/inmunología , Biomarcadores , Gatos , Recuento de Células , Diferenciación Celular/fisiología , Movimiento Celular/fisiología , Corteza Cerebelosa/citología , Corteza Cerebelosa/crecimiento & desarrollo , Coristoma/metabolismo , Femenino , Inmunohistoquímica , Interneuronas/citología , Masculino
10.
Brain Res Bull ; 59(1): 35-40, 2002 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-12372546

RESUMEN

2,3-Benzodiazepines represent a family of specific, noncompetitive AMPA receptor antagonists with anticonvulsant and neuroprotective properties. In this study, the antiexcitotoxic potency of the clinical antiepileptic drug candidate, talampanel (4 x 2 mg/kg), and that of two related 2,3-benzodiazepines, 5-(4-aminophenyl)-8-methyl-9H-1,3-dioxolo[4,5-h][2,3]-benzodiazepine (GYKI 52466) (4 x 10 mg/kg) and GYKI 53784 (4 x 2 mg/kg), was investigated in 7-day-old rats. The AMPA antagonists were applied in four consecutive i.p. injections at 1-h intervals, the first dosage was given shortly after the intrastriatal injection of (S)-alpha-amino-3-hydroxy-5,7-methylisoxazole-4-propionic acid (AMPA) (2.5 nmol). All tested compounds protected animals from brain damage induced by AMPA as assessed 5 days later by using a tissue volume determination method based on computer-aided serial section reconstruction. GYKI 53784 (56.1 +/- 5.0% protection) and talampanel (42.5 +/- 5.3% protection) were more potent neuroprotective agents than GYKI 52466 (21.8 +/- 2.8% protection). Furthermore, the three compounds attenuated the unilateral AMPA injection-induced turning behavior and seizure-like events.Our present findings are in agreement with those of other investigators who found talampanel neuroprotective in various in vivo experimental models. These data indicate that besides being a promising antiepileptic drug candidate talampanel may have a value in the pharmacotherapy of acute and chronic neurodegenerative diseases, including perinatal ischemia/hypoxia-induced brain injuries, as well.


Asunto(s)
Asfixia Neonatal/tratamiento farmacológico , Benzodiazepinas/farmacología , Epilepsia/tratamiento farmacológico , Antagonistas de Aminoácidos Excitadores/farmacología , Hipoxia-Isquemia Encefálica/tratamiento farmacológico , Neostriado/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Animales , Animales Recién Nacidos , Ansiolíticos/farmacología , Asfixia Neonatal/metabolismo , Asfixia Neonatal/fisiopatología , Conducta Animal/efectos de los fármacos , Conducta Animal/fisiología , Muerte Celular/efectos de los fármacos , Muerte Celular/fisiología , Epilepsia/metabolismo , Epilepsia/fisiopatología , Femenino , Ácido Glutámico/metabolismo , Humanos , Hipoxia-Isquemia Encefálica/metabolismo , Hipoxia-Isquemia Encefálica/fisiopatología , Recién Nacido , Masculino , Trastornos del Movimiento/tratamiento farmacológico , Trastornos del Movimiento/fisiopatología , Neostriado/metabolismo , Neostriado/fisiopatología , Neurotoxinas/metabolismo , Ratas , Receptores AMPA/agonistas , Receptores AMPA/antagonistas & inhibidores , Receptores AMPA/metabolismo , Transmisión Sináptica/efectos de los fármacos , Transmisión Sináptica/fisiología , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiónico/toxicidad
11.
J Chromatogr A ; 966(1-2): 145-53, 2002 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-12214688

RESUMEN

The numerous research groups and researchers, as well as IUPAC, that during the last half century have dealt with different theoretical and practical problems in gas-liquid chromatography (GLC), including its nomenclature, have failed in giving an exact definition equation of the net retention time. Using our earlier results and starting from a time balance of GLC we have solved this problem by introducing the so-called acceleration time, t(ac), in the absence of which, the theoretical plate number concept, including the stationary phase transfer, is misinterpreted. The measurements were carried out both on support coated and on wall-coated open tubular columns with apolar and polar stationary phases. Different relationships of t(ac) with some solute properties and the column temperature for a series of n-alkanes on an apolar stationary phase under isothermal conditions were tested. The results obtained are presented in different tables and mathematical relationships.


Asunto(s)
Cromatografía de Gases/métodos , Modelos Teóricos
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