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1.
Cryo Letters ; 41(6): 317-322, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33990807

RESUMEN

BACKGROUND: Although potato as a crop is commercially grown from seed tubers, plants grown from tissue culture plantlets are often used in physiological studies including freezing tolerance determination. OBJECTIVE: This study aimed to examine the effects of the source of plants on freezing tolerance of potato plants at young developmental stages. MATERIALS AND METHODS: We compared freezing tolerance and contents of soluble proteins and sugars of Solanum tuberosum plants derived from tissue culture with those derived from tubers before and after cold acclimation. RESULTS: Tuber-derived plants showed significantly higher freezing tolerance than tissue-culture-derived plants after cold acclimation, although non-acclimated plants did not show any marked differences. Soluble protein contents were higher in tuber-derived plants regardless of cold acclimation. Sucrose content increased to a higher level in tuber-derived plants after cold acclimation. CONCLUSION: These results suggest that source of plant tissue can have a significant effect on the response of young potato plants to freezing stress and that the use of tissue culture plants in freezing tolerance studies may not accurately reflect the frost tolerance of commercially grown plants.


Asunto(s)
Criopreservación , Congelación , Tubérculos de la Planta , Semillas , Solanum tuberosum
2.
J Nutr Health Aging ; 19(7): 719-28, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26193854

RESUMEN

BACKGROUND/OBJECTIVES: Serum polyunsaturated fatty acid (PUFA) composition reflects dietary intake and is related to risks for cardiovascular diseases. We hypothesized that serum n-3 PUFA composition, especially including long-chain n-3 PUFA such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), is associated with inflammatory status, which is related to increased risk for cardiovascular diseases. SUBJECTS/METHODS: We investigated the relationship between serum PUFA composition and high-sensitivity C-reactive protein (hs-CRP) levels in a cross-sectional study among 1,102 healthy men and women aged 40-74 years who reside in Kobe City. Multiple linear regression models that predict hs-CRP level were prepared to confirm the contribution of serum total n-3 PUFA, long-chain n-3 PUFA, EPA and DHA compositions after adjusting for other PUFAs and atherosclerotic risk factors. RESULTS: The serum n-3 PUFA, particularly long-chain n-3 PUFA, compositions were inversely associated with the hs-CRP levels. The standardized regression coefficient was -0.089 (p < 0.01) for total n-3 PUFA, -0.091 (p < 0.01) for long-chain n-3 PUFA, -0.071 (p = 0.03) for EPA, and -0.068 (p = 0.04) for DHA. The n-6 PUFA compositions were also inversely associated with the hs-CRP levels (-0.169 [p < 0.01] for total n-6 PUFA and -0.159 [p < 0.01] for linoleic acid). CONCLUSIONS: The serum n-3 PUFA compositions were inversely related with the hs-CRP levels, similar associations were also observed in n-6 PUFA compositions. Our results suggest that dietary PUFA intake was inversely associated with attenuated inflammation in healthy Japanese population.


Asunto(s)
Pueblo Asiatico , Proteína C-Reactiva/análisis , Ácidos Grasos Omega-3/sangre , Ácidos Grasos Omega-6/sangre , Salud , Adulto , Anciano , Enfermedades Cardiovasculares/sangre , Ciudades , Estudios Transversales , Dieta , Ácidos Docosahexaenoicos/sangre , Ácido Eicosapentaenoico/sangre , Ácidos Grasos Omega-3/química , Femenino , Encuestas Epidemiológicas , Humanos , Inflamación/sangre , Japón , Masculino , Persona de Mediana Edad , Factores de Riesgo
3.
Acta Biomater ; 6(8): 3187-92, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20197125

RESUMEN

Polymethylmethacrylate-based cements containing magnetite (Fe(3)O(4)) particles were prepared and their structure and properties were investigated. The Fe(3)O(4) particles were uniformly dispersed in the cement matrix and constituted a maximum of 60 wt.% of the total weight of cement. The setting time of the cement increased and the maximum temperature during the setting reaction decreased with increasing Fe(3)O(4) content. The compressive strength of cement increased with increasing Fe(3)O(4) content. Cement with 50 wt.% Fe(3)O(4) particles generated heat in alternating magnetic fields of 300 and 120 Oe at a frequency of 100 kHz.


Asunto(s)
Cementos para Huesos/uso terapéutico , Óxido Ferrosoférrico/química , Hipertermia Inducida/métodos , Neoplasias/terapia , Polimetil Metacrilato/química , Cementos para Huesos/farmacología , Fuerza Compresiva/efectos de los fármacos , Microscopía Electrónica de Rastreo , Polvos , Propiedades de Superficie/efectos de los fármacos , Temperatura , Factores de Tiempo , Difracción de Rayos X
4.
Synapse ; 52(1): 29-37, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-14755630

RESUMEN

PET-imaging of the sigma receptors is very helpful to understand processes, e.g., several central nervous system (CNS)-diseases in which the sigma receptors are involved. The [(18)F]fluoroethylated analogs of SA4503 and SA5845 ([(18)F]FE-SA4503 and [(18)F]FE-SA5845) were evaluated in conscious monkeys to estimate its suitability for human application for PET. Conscious monkeys (Macaca Mulatta) were either scanned with [(18)F]FE-SA4503 or [(18)F]FE-SA5845 (n = 3 for both groups, 220-802 MBq). After a dynamic study of 120 min, radioactivity was displaced by intravenous (i.v.) injection of haloperidol (1 mg/kg). One month later the same set of three monkeys were scanned with [(18)F]FE-SA4503 for 120 min and "cold" SA4503 (1 mg/kg) was infused to displace the radioactivity, and the other three monkeys were pretreated with haloperidol (1 mg/kg) before the 120-min PET-scan with [(18)F]FE-SA5845. Cortical areas (cingulate, frontal, occipital, parietal, temporal), striatum, and thalamus showed high radioactivity uptake. Infusion of haloperidol displaced the radioactivity levels of the two radioligands. The same effect was found for [(18)F]FE-SA4503 after SA4503 displacement. Pretreatment with haloperidol blocked the [(18)F]FE-SA5845 binding to give PET-images with low and uniform uptake in the brain. The findings demonstrated the reversible binding of the two radioligands. Metabolite analysis showed that 14% and 23% parent compound of [(18)F]FE-SA5845 and [(18)F]FE-SA4503, respectively, at 120 min postinjection was present in plasma. Kinetic analysis showed that the binding potential of [(18)F]FE-SA5845 was higher in all brain regions than that of [(18)F]FE-SA4503 (4.75-8.79 vs. 1.65-4.04). The highest binding potential was found in the hippocampus, followed by the cortical regions, thalamus, cerebellar hemisphere, striatum and vermis. Both [(18)F]FE-SA compounds bound specifically to cerebral sigma receptors of the monkey and have potential for mapping sigma receptors in the human brain.


Asunto(s)
Química Encefálica/fisiología , Mapeo Encefálico/métodos , Radioisótopos de Flúor , Receptores sigma/metabolismo , Tomografía Computarizada de Emisión/métodos , Animales , Antipsicóticos/farmacología , Unión Competitiva , Cerebelo/metabolismo , Corteza Cerebral/metabolismo , Estado de Conciencia , Cuerpo Estriado/metabolismo , Haloperidol/farmacología , Hipocampo/metabolismo , Ligandos , Macaca mulatta , Masculino , Piperazinas/química , Piperazinas/farmacocinética , Tálamo/metabolismo
5.
Dev Biol ; 214(1): 38-45, 1999 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-10491255

RESUMEN

Retinoic acid-treated mesenchyme cells of the budding ascidian Polyandrocarpa misakiensis acquire an organizer activity to induce a secondary body axis when implanted into developing buds. We identified several different mRNAs that were upregulated in the mesenchyme cells after retinoic acid treatment. We isolated a cDNA clone corresponding to one of these mRNAs. The C-terminal region of the predicted protein product is homologous to the catalytic domain of serine proteases that belong to the trypsin family. The N-terminal region contains several types of protein-protein interaction domains. We therefore named this protein tunicate retinoic acid-inducible modular protease (TRAMP). Expression of the TRAMP mRNA in mesenchyme cells during budding and its upregulation by retinoic acid were demonstrated by reverse transcription-PCR and in situ hybridization. A glutathione S-transferase-TRAMP fusion protein showed a protease activity with trypsin-like substrate specificity and stimulated proliferation of the cell line established in this species.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica , Serina Endopeptidasas/genética , Tretinoina/farmacología , Urocordados/enzimología , Urocordados/crecimiento & desarrollo , Secuencia de Aminoácidos , Animales , Clonación Molecular , ADN Complementario , Inducción Enzimática , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Humanos , Datos de Secuencia Molecular , Especificidad de Órganos , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Serina Endopeptidasas/biosíntesis , Serina Endopeptidasas/química , Transcripción Genética/efectos de los fármacos , Urocordados/genética
6.
J Comp Neurol ; 408(2): 147-60, 1999 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-10333267

RESUMEN

Pax-6, a transcription regulatory factor, has been demonstrated to play important roles in eye, nose, and brain development by analyzing mice, rats, and humans with a Pax-6 gene mutation. We examined the role of Pax-6 with special attention to the formation of efferent and afferent pathways of the cerebral cortex by using the rat Small eye (rSey2), which has a mutation in the Pax-6 gene. In rSey2/rSey2 fetuses, cortical efferent axons develop with normal trajectory, at least within the cortical anlage, when examined with immunohistochemistry of the neuronal cell adhesion molecule TAG-1 and 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiI) labeling from the cortical surface. A remarkable disorder was found in the trajectory of dorsal thalamic axons by immunostaining of the neurofilament and the neural cell adhesion molecule L1 and DiI labeling from the dorsal thalamus. In normal rat fetuses, dorsal thalamic axons curved laterally in the ventral thalamus without invading a Pax-6-immunoreactive cell cluster in the ventral part of the ventral thalamus. These axons then coursed up to the cortical anlage, passing just dorsal to another Pax-6-immunoreactive cell cluster in the amygdaloid region. In contrast, in rSey2/rSey2 fetuses, dorsal thalamic axons extended downward to converge in the ventrolateral corner of the ventral thalamus and fanned out in the amygdaloid region without reaching the cortical anlage. These results suggest that Pax-6-expressing cell clusters along the thalamocortical pathway (ventral part of the ventral thalamus and amygdala) are responsible for the determination of the axonal pathfinding of the thalamocortical pathway.


Asunto(s)
Vías Aferentes/embriología , Corteza Cerebral/embriología , Proteínas de Unión al ADN/fisiología , Vías Eferentes/embriología , Desarrollo Embrionario y Fetal , Proteínas de Homeodominio , Tálamo/embriología , Vías Aferentes/citología , Animales , Axones/fisiología , Moléculas de Adhesión Celular Neuronal/análisis , Corteza Cerebral/citología , Contactina 2 , Proteínas de Unión al ADN/genética , Vías Eferentes/citología , Anomalías del Ojo/genética , Proteínas del Ojo/genética , Proteínas del Ojo/fisiología , Feto , Homocigoto , Inmunohistoquímica , Complejo de Antígeno L1 de Leucocito , Glicoproteínas de Membrana/análisis , Ratones , Moléculas de Adhesión de Célula Nerviosa/análisis , Factor de Transcripción PAX6 , Factores de Transcripción Paired Box , Mutación Puntual , Ratas , Ratas Sprague-Dawley , Proteínas Represoras , Tálamo/citología
7.
Dev Growth Differ ; 40(6): 651-8, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9865975

RESUMEN

Two series of experiments were performed to identify the inhibitory center of the melanotropes in the intermediate lobe of hypophysis of the toad, Bufo japonicus. First, developmental changes in the distribution of dopaminergic neurons were examined from hatching stage to postmetamorphosis using an antiserum against dopamine synthase (tyrosine hydroxylase, TH). In the postmetamorphic toads, TH-positive cell bodies were localized in three clusters. One was the preoptic recess organ (PRO) in the prechiasmatic area, the other two were the paraventricular organ (PVO) and infundibular nucleus (IN) in the postchiasmatic area. Each of them exhibited different ontogenetic changes. During larval development, TH-positive cell bodies were first detected in the PVO and IN at a premetamorphic stage. The number of immunoreactive cells increased rapidly in both loci as metamorphosis proceeded, although the two nuclei showed different growth profiles. By contrast, in the PRO, a very small number of immunoreactive cells were observed before the onset of the prometamorphic period. Although the number of immunoreactive neurons increased as metamorphosis progressed, early neurons were confined to the caudal area of the PRO (cPRO), the rostral area of the PRO (rPRO) being devoid of TH-positive cells. Immunoreactive TH neurons appeared in the rPRO for the first time at the end of metamorphic climax. This timing coincided well with the development of TH-positive nerve endings in the pars intermedia (PI) and median eminence. In the second series of experiments, the embryonic primordium of the PRO was surgically extirpated from open neurulae to examine the effects of PRO-ectomy. In 75% of the operated animals, background adaptation was not observed, their dermal melanophores remained permanently dispersed even on the white background. Dopaminergic neurons in the rPRO and the immunoreactive nerve endings in the PI and median eminence were scarcely observed in these animals. It was concluded that the present data strongly support the hypothesis that rPRO is the center of white-background adaptation.


Asunto(s)
Química Encefálica/fisiología , Bufonidae/fisiología , Hipotálamo/fisiología , alfa-MSH/metabolismo , Animales , Bufonidae/embriología , Bufonidae/crecimiento & desarrollo , Dopamina/metabolismo , Hipotálamo/embriología , Hipotálamo/cirugía , Inmunohistoquímica , Metamorfosis Biológica , Terminaciones Nerviosas/química , Hipófisis/química , Distribución Tisular , Tirosina 3-Monooxigenasa/inmunología
8.
Dev Genes Evol ; 208(10): 537-46, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9811972

RESUMEN

Retinoic acid is thought to induce transdifferentiation of multipotent epithelial stem cells in the developing buds of the ascidian Polyandrocarpa misakiensis. We isolated a cDNA clone from this species, named PmRAR, encoding a retinoic acid receptor (RAR) homologue. PmRAR clusters with other RARs on phylogenetic trees constructed by three different methods. Within the cluster, PmRAR is on a separate branch from all the subtypes of RARs, suggesting that RAR subtypes arose in the ancestral vertebrates after divergence of vertebrates and urochordates. The embryos of another ascidian species Ciona intestinalis were co-electroporated with a mixture of a PmRAR expression vector and a lacZ reporter plasmid containing vertebrate-type retinoic acid response elements. The expression of lacZ depended on the presence of both retinoic acid and PmRAR, suggesting that PmRAR is a functional receptor. PmRAR mRNA is expressed in the epidermis and mesenchyme cells of the Polyandrocarpa developing bud. The mRNA is not detectable in the mesenchyme cells in the adult body wall, but its expression can be induced by retinoic acid in vitro. These results suggest that the PmRAR is a mediator of retinoic acid signalling in transdifferentiation during asexual reproduction of protochordates.


Asunto(s)
Receptores de Ácido Retinoico/genética , Receptores de Ácido Retinoico/metabolismo , Urocordados/genética , Urocordados/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Cartilla de ADN/genética , ADN Complementario/genética , Regulación del Desarrollo de la Expresión Génica , Humanos , Hibridación in Situ , Modelos Biológicos , Datos de Secuencia Molecular , Filogenia , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Homología de Secuencia de Aminoácido , Transducción de Señal , Especificidad de la Especie , Urocordados/crecimiento & desarrollo
9.
Arch Histol Cytol ; 61(3): 189-98, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9756096

RESUMEN

Recent progress in the experimental morphology of the development of amphibian pituitary gland is reviewed. A series of transplantation experiments were carried out using wild-type embryos of the toad as a donor and albino embryos as a recipient. Melanin granules in the wild-type cells allowed tracing of the developmental fate of the grafts as a visible cell marker. These studies have demonstrated that the pituitary gland is not a stomodeal derivative, as it has long been believed to be under the name of "Rathke's pouch". The adenohypophysis is of neural origin. The anterior part of the neural ridge (ANR) in the neuroectoderm of the open neurula gives rise to the whole adenohypophysis, i. e., pars distatis, pars intermedia and pars tuberalis. The presumptive hypothalamus is apposed caudally to the pituitary primordium. A part of the ANR contributes neurons to the preoptic hypothalamus even after closure of the neural tube. The anlagen of the olfactory system, which include the nasal epithelia and the olfactory bulbs, are situated on both sides of the pituitary primordium in the neural ridge. In both hypothalamic-hypophyseal and olfactory systems, the peripheral and central parts derive from closely affiliated cell populations, suggesting their clonal relationships. Development of the hypophysis and hypothalamus is interdependent. On one hand, a connection with the embryonic hypothalamus is essential for the pituitary proopiomelanocortin cells to develop. On the other hand, neither the hypothalamic median eminence nor its axonal supply develops without the presence of the pituitary primordium. Novel aspects of the ontogeny and phylogeny of these organs are discussed with special reference to the role of the neural ridge in the generation of a spectrum of chemoreceptive organs.


Asunto(s)
Hipotálamo/embriología , Hipófisis/embriología , Animales , Axones , Eminencia Media/embriología , Morfogénesis , Vías Olfatorias/embriología , Filogenia
10.
J Comp Neurol ; 382(2): 141-52, 1997 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-9183685

RESUMEN

We used immunohistochemistry to examine possible molecular interactions between the subplate and growing thalamocortical axons in rat fetuses. In the cortical anlage of embryonic day 16 (E16), the subplate first appeared below the cortical plate. Among chondroitin sulfate proteoglycans, phosphacan was uniformly distributed throughout the cortical wall, whereas neurocan was localized only in the subplate at E16. Neural cell adhesion molecules, NCAM-H, TAG-1, and L1, were detected in the cortical anlage. Both cortical neurons and growing axons were diffusely immunopositive for NCAM-H, and TAG-1 immunoreactivity was found on immature neurons and cortical efferent axons but not on thalamocortical axons. L1 immunoreactivity was specifically localized on the growing thalamocortical axons. When the locations of neurocan and L1 were compared in the developing cortex, L1-bearing axons were found to extend to neurocan-immunopositive regions; neurocan immunoreactivity was intense in the subplate at E16, when small numbers of L1-immunoreactive thalamocortical axons began to invade the cortex. At E17, many L1-positive axons were observed in the subplate that expressed neurocan specifically. Double immunostaining showed that L1-positive axons and neurocan immunoreactivity overlapped in the subplate at E17. After E18, neurocan expression gradually extended to the lower part of the cortical plate; it extended to the entire cortex by E21, 1 day before birth. By E21, L1-bearing axons had invaded the lower part of the cortical plate. The present study demonstrated that the neurocan expression precedes growth of L1-bearing thalamocortical afferent fibers. Because neurocan can bind to L1 molecule in vitro, these results suggest that neurocan and L1 play some important roles in pathfinding of the thalamocortical afferent fibers during rat corticogenesis.


Asunto(s)
Moléculas de Adhesión Celular Neuronal , Corteza Cerebral/embriología , Proteoglicanos Tipo Condroitín Sulfato/biosíntesis , Regulación del Desarrollo de la Expresión Génica , Glicoproteínas de Membrana/biosíntesis , Proteínas del Tejido Nervioso/biosíntesis , Neuronas/fisiología , Tálamo/embriología , Animales , Axones/fisiología , Corteza Cerebral/citología , Corteza Cerebral/metabolismo , Proteoglicanos Tipo Condroitín Sulfato/análisis , Contactina 2 , Desarrollo Embrionario y Fetal , Inmunohistoquímica/métodos , Lectinas Tipo C , Complejo de Antígeno L1 de Leucocito , Glicoproteínas de Membrana/análisis , Proteínas del Tejido Nervioso/análisis , Moléculas de Adhesión de Célula Nerviosa/análisis , Moléculas de Adhesión de Célula Nerviosa/biosíntesis , Neurocano , Neuronas/citología , Ratas , Ratas Sprague-Dawley , Tálamo/citología , Tálamo/metabolismo
11.
Heart Vessels ; 12(3): 143-51, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9496465

RESUMEN

Nifedipine (20 mg/kg/day) was given to 15-week-old spontaneously hypertensive rats for 20 weeks (SHR-N, n = 8). Comparison was done with sex-matched 15-week-old SHR (SHR-15, n = 7), untreated 35-week-old SHR (SHR-C, n = 10), 15-week-old normotensive Wistar-Kyoto rats (WKY-15, n = 15), and 35-week-old WKY (WKY-15, n = 5). Light and electron microscopic data on the subepicardial, middle and subendocardial layers and papillary muscles of the left ventricle were compared among the five rat groups. In SHR-N, blood pressure was significantly reduced by nifedipine, but was higher than in WKY-35 (199 +/- 11 mmHg vs 121 +/- 13 mmHg). The left ventricular weight/body weight ratio was much lower in SHR-N than in SHR-C, and was even below the baseline value in SHR-15. In addition, cardiac myocyte diameter was much smaller in each myocardial layer of SHR-N than in SHR-C, and was similar to the findings in SHR-15, but still larger than in WKY-35. The interstitial area ratio was markedly reduced in SHR-N and did not differ from that in SHR-15 or even WKY-15, while capillary density was significantly greater than in SHR-C and comparable to that in WKY-35. In SHR-C, large fibrotic foci were common, and many hypertrophic cardiac myocytes showed various degenerative changes including those of mitochondria and widening of the intermyofibrillar spaces. These changes were rarely seen in SHR-N. The intracellular volume ratio of myofibrils did not differ between SHR-N and WKY-35, but was significantly decreased in SHR-C, whereas that of mitochondria did not differ between SHR-N and SHR-C or WKY-35. These findings indicate that despite only a moderate suppression of hypertension, long-term nifedipine treatment caused regression of left ventricular hypertrophy, with cardiocyte hypertrophy, interstitial fibrosis, degenerative changes, and subcellular remodeling being reversed to the baseline levels in SHR-15. In addition, the capillary density was increased to that seen in WKY-35.


Asunto(s)
Hipertrofia Ventricular Izquierda/tratamiento farmacológico , Hipertrofia Ventricular Izquierda/patología , Miocardio/ultraestructura , Nifedipino/uso terapéutico , Animales , Presión Sanguínea/efectos de los fármacos , Capilares/patología , Tamaño de la Célula , Ventrículos Cardíacos/patología , Hipertensión/complicaciones , Hipertrofia Ventricular Izquierda/etiología , Masculino , Mitocondrias Cardíacas/ultraestructura , Miocardio/patología , Nifedipino/farmacología , Tamaño de los Órganos , Músculos Papilares/patología , Músculos Papilares/ultraestructura , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas WKY , Especificidad de la Especie
12.
Genes Dev ; 9(24): 3109-21, 1995 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-8543155

RESUMEN

We generated mice carrying a loss-of-function mutation in Brn-2, a gene encoding a nervous system specific POU transcription factor, by gene targeting in embryonic stem cells. In homozygous mutant embryos, migratory precursor cells for neurons of the paraventricular nuclei (PVN) and the supraoptic nuclei (SO) of the hypothalamus die at approximately E12.5. All homozygous mutants suffered mortality within 10 days after birth, possibly because of a complete deficiency of these neurons in the hypothalamus. Although neither developmental nor histological abnormalities were observed in heterozygous mice, the levels of expression of vasopressin and oxytocin in the hypothalamus of these animals were half these of wild-type mice. These results strongly suggest that Brn-2 plays an essential role in the determination and development of the PVN and SO neuronal lineages in the hypothalamus.


Asunto(s)
Hipotálamo/citología , Neuronas/citología , Factores de Transcripción/metabolismo , Animales , Secuencia de Bases , Línea Celular , Movimiento Celular , Cartilla de ADN , Embrión de Mamíferos/metabolismo , Embrión de Mamíferos/patología , Genes Letales , Mutación de Línea Germinal , Proteínas de Homeodominio , Homocigoto , Hipotálamo/metabolismo , Ratones , Datos de Secuencia Molecular , Neuronas/metabolismo , Factores del Dominio POU , Neurohipófisis/embriología , Neurohipófisis/patología , Somatostatina/biosíntesis , Factores de Transcripción/genética
13.
Anat Embryol (Berl) ; 190(2): 137-54, 1994 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7818087

RESUMEN

The interactions between growing thalamocortical afferent axons and the neocortical primordium were examined during neocortical development of the mouse cerebrum, by labeling the afferents with the carbocyanine fluorescent dye, DiI, which was introduced into the dorsal thalamus of the fixed brains of control and reeler mutant mice. In the neocortical primordium of the control mouse, the labeled afferents running tangentially in the intermediate zone formed a dense plexus in the subplate, the layer below the cortical plate, as early as the 16th gestational day (E16). Small numbers of the afferents invaded the lower cortical plate at E16 and increasing numbers of labeled growing axons extended into the cortical plate at E17. At the 4th postnatal day (P4), labeled afferents grew radially up to the upper cortical plate and terminal arborizations of the afferents were evident in the forming layer IV. In contrast, in the E16 cerebrum of the reeler mutant mouse, in which the cortical layers are inverted, the labeled afferents traversed the neocortical primordium directly towards the superplate, the superficial layer above the cortical plate and the equivalent of the subplate in the control mouse. Thick bundles of labeled axons reached the superplate and made contact with the superplate neurons. At P4 in the reeler neocortex, the afferent axons that had reached the superplate began to change their direction of growth and turned towards the deeper layer. Electron-microscopic observations at E16 revealed that immature synapses were formed on the somata of the subplate neurons in the control mouse, and similar immature synapses were also formed on the superplate neurons of the reeler mutant. At E16 in the control, NGF receptor immunoreactivity was expressed in the intermediate zone, subplate and lower cortical plate, and the mode of expression corresponded to the distribution of thalamocortical afferents. At the same stage of the reeler mutant, expression of NGF receptor immunoreactivity was confined to the afferent axons that had grown through the neocortical primordium towards the superplate. In the control at E17, highly polysialylated NCAM (NCAM-H), a homophilic cell adhesion molecule, was expressed in the subplate, marginal zone and afferent axons. In the reeler mutant at the same stage, this adhesion molecule was expressed in both the superplate and the bundles of the afferent axons. These findings suggest that the subplate and the superplate, which are composed of neurons generated at the earliest stage, attract growing thalamocortical afferent axons specifically by a chemotropic mechanism through the expression of NGF receptor.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Animales Recién Nacidos/fisiología , Corteza Cerebral/embriología , Corteza Cerebral/fisiología , Embrión de Mamíferos/fisiología , Ratones Mutantes Neurológicos/fisiología , Tálamo/embriología , Tálamo/fisiología , Vías Aferentes/embriología , Vías Aferentes/fisiología , Vías Aferentes/ultraestructura , Envejecimiento , Animales , Animales Recién Nacidos/anatomía & histología , Animales Recién Nacidos/crecimiento & desarrollo , Axones/fisiología , Moléculas de Adhesión Celular Neuronal/metabolismo , Corteza Cerebral/ultraestructura , Embrión de Mamíferos/ultraestructura , Desarrollo Embrionario y Fetal , Ratones , Ratones Mutantes Neurológicos/embriología , Ratones Mutantes Neurológicos/crecimiento & desarrollo , Microscopía Electrónica , Receptores de Factor de Crecimiento Nervioso/metabolismo , Valores de Referencia , Ácidos Siálicos/metabolismo , Tálamo/ultraestructura
14.
Jpn Circ J ; 58(2): 116-22, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8196153

RESUMEN

Left ventricular (LV) performance of the pharmacologically regressed heart in hypertension is still unclear. We compared LV function of the heart regressed by nifedipine with that of the hypertrophied heart in spontaneously hypertensive rats (SHR). Nifedipine (30 mg/kg/day in food) was given to 15-week-old male SHR for 20 weeks (n = 12). Age- and sex-matched SHR served as controls (n = 12). LV catheterization was performed using a micromanometer and cardiac output was determined by the thermodilution method. Hemodynamic studies were performed after washout of nifedipine (24 h), when blood pressure had returned to the untreated level. Peak pumping ability was assessed during acute volume loading with saline. Nifedipine significantly decreased blood pressure in conscious animals (222 +/- 11 to 201 +/- 12 mmHg, p < 0.01) and reduced LV weight (1.20 +/- 0.07 to 1.07 +/- 0.05g, p < 0.01). After washout of nifedipine, LV systolic and end-diastolic pressures, dp/dtmax and cardiac output determined under pentobarbital anesthesia were similar in the treated and untreated groups. Peak pumping ability during acute preload elevation was also similar in the 2 groups. Plasma norepinephrine was unaltered, and plasma renin activity was significantly lower in the treated rats (p < 0.05). These results indicate that nifedipine regressed LVH with a minimal reduction of blood pressure and without evidence of neurohumoral activation or volume retention. In conclusion, LV function of the heart regressed by nifedipine was preserved after a spontaneous rise in blood pressure and during acute preload elevation.


Asunto(s)
Hipertensión/tratamiento farmacológico , Hipertrofia Ventricular Izquierda/tratamiento farmacológico , Nifedipino/uso terapéutico , Función Ventricular Izquierda/efectos de los fármacos , Animales , Presión Sanguínea/efectos de los fármacos , Hemodinámica/efectos de los fármacos , Hipertensión/complicaciones , Hipertrofia Ventricular Izquierda/etiología , Hipertrofia Ventricular Izquierda/fisiopatología , Masculino , Norepinefrina/sangre , Ratas , Ratas Endogámicas SHR , Renina/sangre
15.
Eur Urol ; 25(4): 330-3, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-8056027

RESUMEN

The aim of this study was to find out the influence of radiofrequency (RF) capacitive heating on the alpha 1-adrenergic receptor of rat prostates. The prostates of 30-week-old Wistar rats were submitted to a 1-hour single session of RF capacitive heating at 45 degrees C. The ventral prostates that were submitted to heating were compared to those of other rats that were not submitted to heating. In order to determine the density of alpha 1-adrenergic receptors in rat ventral prostates, binding assays for alpha 1-adrenergic receptor were performed with [3H]prazosin in membrane preparations. The receptor density in the control group was 27.07 +/- 3.75 fmol/mg protein. The alpha 1-adrenergic receptor density (Bmax) in the thermotherapy group was 17.91 +/- 5.15 fmol/mg protein. A remarkable decrease in the density of alpha 1-adrenergic receptors was observed in the rat prostates of the thermotherapy group. In conclusion, the present results demonstrate that heating the rat prostate by RF capacitive heating damages the alpha 1-adrenergic receptors.


Asunto(s)
Hipertermia Inducida/efectos adversos , Próstata/metabolismo , Receptores Adrenérgicos alfa 1/metabolismo , Animales , Masculino , Microondas , Ratas , Ratas Wistar
16.
Hinyokika Kiyo ; 39(11): 993-6, 1993 Nov.
Artículo en Japonés | MEDLINE | ID: mdl-7505524

RESUMEN

Transurethral microwave thermotherapy (TUMT) of prostate was administered to 10 patients with bladder outlet obstruction due to benign prostatic hyperplasia. The mean age of the patients was 74.4 years (range 63 to 85). The Prostatron device, which provides microwave heating of the prostate and conductive cooling of the urethra was used, and the prostate was heated with a calculated intraprostatic temperature of 45.5 degrees C for 55 minutes. No anesthesia was required for most of the patients. The clinical effects were evaluated at 4-6 weeks and 3 months after treatment. The symptomatic scores improved in the majority of patients. There was no significant change in prostate volume. The maximum flow rate and average flow rate were increased at 6 weeks and 3 months, but there was no significant change. The only side effects were transient hematuria and short-term obstruction secondary to urethral edema. In comparing TUMT with the transurethral resection of prostate (TUR-P), the maximum flow rate after TUMT was lower than that after TUR-P and the improvement of residual urine after TUMT was lower than that after TUR-P.


Asunto(s)
Hipertermia Inducida/métodos , Microondas/uso terapéutico , Hiperplasia Prostática/terapia , Anciano , Anciano de 80 o más Años , Humanos , Hipertermia Inducida/instrumentación , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
17.
Hinyokika Kiyo ; 39(8): 695-700, 1993 Aug.
Artículo en Japonés | MEDLINE | ID: mdl-8379469

RESUMEN

The inhibitory effects of Takusha on the formation, growth and aggregation of calcium oxalate crystals were estimated by the microplate method and the use of Coulter counter TAII in the diluted urine system and undiluted urine system. In the diluted urine system, the inhibitory effect on aggregation and growth was calculated from the changes in the number and volume of crystals by the seed crystal method. Takusha had a strong inhibitory effect on the aggregation and growth when the concentration was above 10 micrograms/ml. In measuring the metastable limit by the microplate method, Takusha had a mild inhibitory effect on the formation of crystals above the concentration of 1 mg/ml. In the undiluted urine system, after determining the metastable limit, the formation and growth of calcium oxalate crystals which precipitated in response to a load of sodium oxalate were measured. Takusha had a strong inhibitory effect on the formation and growth at the concentration of 0.1-1 mg/ml. Takusha had no glycosaminoglicans in the dimethylmethylene blue assay and had an inhibitory effect on aggregation and growth when its molecular weight was over 10,000. Therefore, Takusha might be useful for preventing stones in recurrent stone formers.


Asunto(s)
Oxalato de Calcio/orina , Medicamentos Herbarios Chinos/farmacología , Cristalización , Humanos , Masculino , Microscopía Electrónica de Rastreo , Cálculos Urinarios/prevención & control
18.
Horm Metab Res ; 20(11): 671-5, 1988 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-3215628

RESUMEN

The activity of aortic glutathione peroxidase, a selenium-dependent enzyme, significantly decreased in rats 4 and 8 months after the injection of streptozotocin (STZ). Catalase activity was shown to occur at low levels in rat aorta and was not influenced by the diabetic state. Superoxide dismutase activity was less than detectable. The activity of selenium-dependent glutathione peroxidase in kidney, but not in lung and liver, increased in diabetic rats. Catalase and superoxide dismutase activities in the kidney were not altered. The plasma lipid peroxide value increased in diabetic rats. The selenium content in plasma of diabetic rats increased markedly while the increase in plasma glutathione peroxidase activities was insignificant. The observed abnormalities in plasma of STZ rats were improved by insulin treatment. The defects in glutathione peroxidase in the diabetic rat aorta were restored by insulin treatment. These results may suggest that the capacity of the antioxidative defense system in the aorta decreased in the diabetic state, and this may help clarify the mechanism of the pathogenesis of endothelial dysfunction associated with diabetes.


Asunto(s)
Catalasa/metabolismo , Diabetes Mellitus Experimental/enzimología , Glutatión Peroxidasa/metabolismo , Selenio/sangre , Superóxido Dismutasa/metabolismo , Animales , Aorta/enzimología , Diabetes Mellitus Experimental/sangre , Riñón/enzimología , Masculino , Ratas , Ratas Endogámicas
20.
Org Geochem ; 10: 1059-65, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-11542045

RESUMEN

Long-chain fatty acids (C10-C32), as well as C14-C21 isoprenoid acids (except for C18), have been identified in anhydrous and hydrous pyrolyses products of Green River kerogen (200-400 degrees C, 2-1000 hr). These kerogen-released fatty acids are characterized by a strong even/odd predominance (CPI: 4.8-10.2) with a maximum at C16 followed by lesser amounts of C18 and C22 acids. This distribution is different from that of unbound and bound geolipids extracted from Green River shale. The unbound fatty acids show a weak even/odd predominance (CPI: 1.64) with a maximum at C14, and bound fatty acids display an even/odd predominance (CPI: 2.8) with maxima at C18 and C30. These results suggest that fatty acids were incorporated into kerogen during sedimentation and early diagenesis and were protected from microbial and chemical changes over geological periods of time. Total quantities of fatty acids produced during heating of the kerogen ranged from 0.71 to 3.2 mg/g kerogen. Highest concentrations were obtained when kerogen was heated with water for 100 hr at 300 degrees C. Generally, their amounts did not decrease under hydrous conditions with increase in temperature or heating time, suggesting that significant decarboxylation did not occur under the pyrolysis conditions used, although hydrocarbons were extensively generated.


Asunto(s)
Ácidos Carboxílicos/análisis , Ácidos Grasos/análisis , Sedimentos Geológicos/química , Calor , Hidrocarburos/análisis , Carbono/química , Ácidos Carboxílicos/química , Ácidos Grasos/química , Fósiles , Hidrocarburos/química , Petróleo , Termodinámica , Agua/química
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