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1.
Endoscopy ; 44(11): 1007-11, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22930171

RESUMEN

BACKGROUND AND STUDY AIMS: The frequency of stricture after endoscopic submucosal dissection (ESD) for esophageal squamous cell carcinoma with a mucosal defect involving more than three-quarters of the circumference is 70% - 90%. Stricture decreases quality of life and requires multiple endoscopic balloon dilation (EBD) sessions. We investigated the efficacy and safety of a single session of intralesional steroid injections to prevent post-ESD stricture. PATIENTS AND METHODS: We conducted a prospective study on 30 patients with esophageal squamous cell carcinoma treated by ESD, who had a more than three-quarter but less than whole circumferential defect. A single session of intralesional steroid injections was undertaken immediately after ESD. Esophagogastroduodenoscopy was performed whenever patients reported dysphagia and 2 months after ESD in patients without dysphagia. Results were compared with a historical control group of 29 patients who underwent ESD without intralesional steroid injection. The primary endpoint was the post-ESD stricture rate. Secondary endpoints were the number of EBD sessions and the complication rate. RESULTS: Compared with the historical control group, the study group had a significantly lower stricture rate (10%, 3/30 patients vs. 66%, 19/29 patients; P < 0.0001) and a lower number of EBD sessions (median 0, range 0 - 2 vs. median 2, range 0 - 15; P < 0.0001). The study group had a complication rate of 7 % (2 /30 patients), comprising a submucosal tear in one patient and bleeding in another, which were not a direct result of EBD. CONCLUSIONS: A single session of intralesional steroid injections showed promising results for the prevention of stricture after ESD for esophageal cancer.


Asunto(s)
Carcinoma de Células Escamosas/cirugía , Endoscopía Gastrointestinal , Neoplasias Esofágicas/cirugía , Estenosis Esofágica/prevención & control , Triamcinolona Acetonida/administración & dosificación , Anciano , Endoscopía del Sistema Digestivo , Endoscopía Gastrointestinal/métodos , Femenino , Humanos , Inyecciones Intralesiones , Masculino , Complicaciones Posoperatorias/prevención & control , Estudios Prospectivos
2.
J Pediatr Urol ; 14(5): 402-406, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30219308

RESUMEN

INTRODUCTION: Torsion of an undescended testis (UDT) associated with cerebral palsy (CP) and neuromuscular disease (NMD) is an uncommon condition that is not well recognized by primary care physicians or healthcare providers. OBJECTIVE: The objective of this study was to highlight the clinical importance of torsion of a UDT in children with CP and NMD. MATERIALS AND METHODS: Eleven children with testicular torsion of a UDT operated on at the study institute between 1991 and 2015 were identified. The records of seven children (63.6%) associated with CP or NMD were retrospectively reviewed. Clinical findings of testicular torsion were assessed along with the treatment outcome and testicular salvageability. RESULTS: All seven children were not identified with a UDT by public health checkup for infant and young children. No children with CP or NMD had torsion of a descended testis during the present study period. Median age at surgery was 15 years (range, 1-20 years). The testis location was at the external inguinal ring in five patients, in the inguinal canal in one, and in the superficial inguinal pouch in one. Of the contralateral testes, four were a UDT, one was a retractile testis, and two were descended testes. Orchiectomy was performed in six patients (85.7%). In the remaining patients, the testis was preserved but became atrophic. DISCUSSION: This study demonstrated that children with CP or NMD may be affected with torsion of a UDT with peak at around puberty with the poor salvage rate, even if the testes appear descended in infancy and young children. Shortcomings of this study were the retrospective design and a small series of children undergoing surgery for torsion of a UDT. CONCLUSION: Pediatric urologists need to educate primary care physicians and healthcare providers in the recognition of acquired UDTs and possibly associated testicular torsion in children with CP and NMD. Genital examination should be continued regularly until adolescence in these children to detect acquired UDT. These children should be referred to pediatric urologists to promote surgery as soon as the diagnosis of acquired UDT is carried out. It is believed that it is perhaps the best approach to prevent loss of the testis in children with CP and NMD.


Asunto(s)
Parálisis Cerebral/complicaciones , Criptorquidismo/etiología , Enfermedades Neuromusculares/complicaciones , Torsión del Cordón Espermático/etiología , Adolescente , Niño , Preescolar , Humanos , Lactante , Masculino , Estudios Retrospectivos , Adulto Joven
3.
J Neurosci ; 21(4): 1257-64, 2001 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-11160396

RESUMEN

In this report, we investigated whether reactive astrocytes produce neuregulins (glial growth factor 2/heregulin/acetylcholine receptor-inducing activity or neu differentiation factor) and its putative receptors, ErbB2 and ErbB3 tyrosine kinases, in the injured CNS in vivo. Significant immunoreactivities with anti-neuregulin, anti-ErbB2, and anti-ErbB3 antibodies were detected on astrocytes at the injured site 4 d after injury to the adult rat cerebral cortex. To elucidate the mechanisms for the upregulation of neuregulin expression in astrocytes, primary cultured astrocytes were treated with certain reagents, including forskolin, that are known to elevate the intracellular level of cAMP and induce marked morphological changes in astrocytes. Western blot analysis showed that the expression of a 52 kDa membrane-spanning form of a neuregulin protein was enhanced in cultured astrocytes after administration of forskolin. The upregulation of glial fibrillary acidic protein was also observed in astrocytes treated with forskolin. In contrast, inactivation of protein kinase C because of chronic treatment with phorbol ester 12-O-tetradecanoyl phorbol 13-acetate downregulated the expression of the 52 kDa isoform, although other splice variants with apparent molecular sizes of 65 and 60 kDa were upregulated. These results suggest that the enhancement of neuregulin expression at injured sites is induced, at least in part, by elevation in intracellular cAMP levels and/or a protein kinase C signaling pathway. The neuregulin expressed on reactive astrocytes may stimulate their proliferation and support the survival of neurons surrounding cortical brain wounds in vivo.


Asunto(s)
Astrocitos/metabolismo , Lesiones Encefálicas/metabolismo , Corteza Cerebral/metabolismo , Neurregulinas/metabolismo , Animales , Astrocitos/citología , Astrocitos/efectos de los fármacos , Lesiones Encefálicas/patología , Células CHO , Células Cultivadas , Corteza Cerebral/patología , Colforsina/farmacología , Cricetinae , AMP Cíclico/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Modelos Animales de Enfermedad , Proteína Ácida Fibrilar de la Glía/metabolismo , Traumatismos Penetrantes de la Cabeza/metabolismo , Traumatismos Penetrantes de la Cabeza/patología , Neurregulinas/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteína Quinasa C/metabolismo , Ratas , Ratas Sprague-Dawley , Receptor ErbB-2/metabolismo , Receptor ErbB-3/metabolismo , Transducción de Señal/efectos de los fármacos , Acetato de Tetradecanoilforbol , Regulación hacia Arriba
4.
Neuroscience ; 60(1): 145-57, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-8052408

RESUMEN

The mammalian brain contains many species of proteoglycan. To identify each proteoglycan species, we have raised monoclonal antibodies against soluble chondroitin sulfate proteoglycans purified from 10-day-old rat brains. One monoclonal antibody, named monoclonal antibody 1G2, recognized two proteoglycan species with 220,000 and 150,000 mol. wt core glycoproteins (chondroitin sulfate proteoglycan-220 and chondroitin sulfate proteoglycan-150). Partial amino acid sequences of N-termini of their core proteins coincided with those of neurocan, a brain-unique chondroitin sulfate proteoglycan species, whose complete coding sequence was recently reported [Rauch et al. (1992) J. biol. Chem. 269, 19,536-19,547]. Western blots revealed that chondroitin sulfate proteoglycan-220 became detectable in the rat cerebrum on embryonic day 14, and that it disappeared from the brain around postnatal day 30. In contrast, a fairly large amount of chondroitin sulfate proteoglycan-150 remained in the mature brain. Immunohistochemical studies revealed that 1G2 antigen was first localized in the preplate zone, then both in the marginal zone and in the subplate of the rat cerebrum on embryonic day 16, prior to arrival of the first thalamic afferents at the cortex. On embryonic day 20, immunolabeling with monoclonal antibody 1G2 began to spread from the subplate into the developing cortical plate. On postnatal day 10, the neuropil of the cerebrum, except for the barrel field, was diffusely stained with the antibody, intensely in the hippocampus and superficial layers (I-III) of the cerebral cortex and weakly elsewhere. The barrel hollows were stained very weakly compared with the barrel walls at this stage. The immunoreactivity in the hippocampus and superficial cortical layers was weakened in the mature brain, so that no particular staining pattern, but weak and diffuse staining was observed in the adult rat cerebrum. The 1G2 antigen was immunohistochemically associated largely with glial fibrillary acidic protein-positive cells in primary cultures of the neonatal rat cerebrum. Both chondroitin sulfate proteoglycan-220 and chondroitin sulfate proteoglycan-150 were detected in the conditioned media not only of highly enriched cultures of fetal rat cortical neurons but also of pure cultures of mature astrocytes; more (12- to 20-fold) in the astrocyte conditioned media. Astrocytes, in addition to neurons, may be a cellular source of neurocan in brain at least under certain physiological conditions. The spaciotemporal expression pattern of 1G2 epitope-bearing proteoglycan, or neurocan, suggests that this proteoglycan species plays some roles at least in forming the elongation pathway for early cortical afferent fibers as well as the functional barrel structure in the somatosensory cortex.


Asunto(s)
Anticuerpos Monoclonales , Corteza Cerebral/crecimiento & desarrollo , Corteza Cerebral/metabolismo , Proteoglicanos Tipo Condroitín Sulfato/biosíntesis , Proteínas del Tejido Nervioso/biosíntesis , Secuencia de Aminoácidos , Animales , Astrocitos/metabolismo , Western Blotting , Células Cultivadas , Corteza Cerebral/citología , Condroitín Liasas/metabolismo , Proteoglicanos Tipo Condroitín Sulfato/química , Proteoglicanos Tipo Condroitín Sulfato/inmunología , Medios de Cultivo Condicionados , Electroforesis en Gel de Poliacrilamida , Femenino , Glucosidasas/química , Hidrólisis , Inmunohistoquímica , Lectinas Tipo C , Ratones , Ratones Endogámicos C3H/inmunología , Datos de Secuencia Molecular , Proteínas del Tejido Nervioso/química , Proteínas del Tejido Nervioso/inmunología , Neurocano , Embarazo , Proteoglicanos/biosíntesis , Proteoglicanos/química , Proteoglicanos/inmunología , Ratas , Ratas Sprague-Dawley
5.
Neuroscience ; 112(4): 773-81, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12088737

RESUMEN

Neurocan is one of the major chondroitin sulfate proteoglycans expressed in nervous tissues. The expression of neurocan is developmentally regulated, and full-length neurocan is detected in juvenile brains but not in adult brains. In the present study, we demonstrated by western blot analysis that full-length neurocan transiently appeared in adult rat hippocampus when it was lesioned by kainate-induced seizures. Immunohistochemical studies showed that neurocan was detected mainly around the CA1 region although the seizure resulted in neuronal cell degeneration in both the CA1 and CA3 regions of the hippocampus. Double-labeling for neurocan mRNA and glial fibrillary acidic protein demonstrated that many reactive astrocytes expressed neurocan mRNA. The re-expression of full-length neurocan was also observed in the surgically injured adult rat brain. In contrast, the expression of other nervous tissue chondroitin sulfate proteoglycans, such as phosphacan and neuroglycan C, was not intensified but rather was either reduced in the kainate-lesioned hippocampus or in the surgically injured cerebral cortex. These observations indicate that induction of neurocan expression by reactive astrocytes is a common phenomenon in the repair process of adult brain injury, and therefore, it can be postulated that juvenile-type neurocan plays some roles in brain repair.


Asunto(s)
Astrocitos/metabolismo , Lesiones Encefálicas/metabolismo , Proteoglicanos Tipo Condroitín Sulfato/metabolismo , Hipocampo/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Convulsiones/metabolismo , Animales , Western Blotting , Proteoglicanos Tipo Condroitín Sulfato/genética , Proteína Ácida Fibrilar de la Glía/metabolismo , Inmunohistoquímica , Ácido Kaínico , Lectinas Tipo C , Glicoproteínas de Membrana/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas del Tejido Nervioso/genética , Neurocano , Proteoglicanos/metabolismo , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Proteínas Tirosina Fosfatasas Clase 5 Similares a Receptores , Convulsiones/inducido químicamente , Sindecano-3 , Factores de Tiempo
6.
J Biochem ; 99(5): 1371-6, 1986 May.
Artículo en Inglés | MEDLINE | ID: mdl-3086307

RESUMEN

In order to investigate the involvement of cartilage proteoglycans in the pathogenesis of human congenital skeletal disorders, proteoglycans were extracted with 4 M guanidine HCl from the iliac crest cartilage of children with various skeletal diseases; lysosomal storage diseases (group I), osteochondrodysplasias (group II) and controls (group III). The cartilage-type proteoglycan (PG-H) was purified and its chondroitin sulfate moiety was analyzed by digestion with chondroitinase-ABC. In group II and group III, the relative amounts of the unsaturated disaccharide products changed in an age-related manner; decrease (from 50% to 30%) of delta Di-4S with a compensatory increase (from 40% to 60%) of delta Di-6S with increasing age from 0 to 15 years. On the other hand, some cases in group I showed aberrant composition of the disaccharide products; a lower content of delta Di-4S with a correspondingly higher content of delta Di-6S. Patients in group I have clinically similar skeletal disorders, and the extent of the compositional abnormality seems to reflect the severity of the skeletal disorder. Therefore, one may consider that the aberrant composition of the glycosaminoglycans in PG-H is involved in the pathogenesis of the skeletal disorder of lysosomal storage diseases.


Asunto(s)
Enfermedades Óseas/metabolismo , Cartílago/metabolismo , Sulfatos de Condroitina/aislamiento & purificación , Condroitín/análogos & derivados , Errores Innatos del Metabolismo/metabolismo , Proteoglicanos/aislamiento & purificación , Adolescente , Enfermedades Óseas/etiología , Niño , Preescolar , Cromatografía en Gel , Femenino , Humanos , Ilion , Recién Nacido , Masculino , Errores Innatos del Metabolismo/complicaciones
7.
Neurochem Int ; 25(5): 425-31, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7849571

RESUMEN

Neurocan is a brain-unique chondroitin sulfate proteoglycan (CSPG) whose expression and proteolytic cleavage are developmentally regulated. One of the proteolytic products (C-terminal half) is known to be a CSPG with a 150 kDa core glycoprotein (CSPG-150). To identify the N-terminal half of neurocan, we raised an anti-neurocan polyclonal antibody (PAb 291) using a synthetic peptide whose amino acid sequence matched a part of the N-terminal half of neurocan. Western blots showed that PAb 291 recognized two CSPGs, one with a 220 kDa core glycoprotein (CSPG-220, namely neurocan) and one with a 130 kDa core glycoprotein (CSPG-130) isolated from young rat brains. CSPG-130 was co-purified along with CSPG-220 by PAb 291-immunoaffinity column chromatography. The amino acid sequence of the N-terminus of the immunopurified CSPG-130 was exactly the same as the N-terminal sequence of CSPG-220. These results suggest that not only the C-terminal half (CSPG-150) but also the N-terminal half (CSPG-130) of CSPG-220 exists in a CSPG form in rat brain. Using PAb 291 and monoclonal antibody 1G2 (MAb 1G2) which recognizes CSPG-150 in addition to CSPG-220, we found that the contents of CSPG-130 and CSPG-150 in the rat brain reached maximum levels around the time of birth. Both CSPG-130 and 150 were observed, while CSPG-220 was hardly detectable in extracts from the adult rat brain. Immunohistochemical investigation showed that the PAb 291 antigen had a similar distribution pattern to the MAb 1G2 antigen.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Encéfalo/metabolismo , Proteoglicanos Tipo Condroitín Sulfato/análisis , Proteoglicanos Tipo Condroitín Sulfato/metabolismo , Proteínas del Tejido Nervioso/análisis , Fragmentos de Péptidos/análisis , Secuencia de Aminoácidos , Animales , Encéfalo/embriología , Encéfalo/crecimiento & desarrollo , Proteoglicanos Tipo Condroitín Sulfato/química , Inmunoensayo , Inmunohistoquímica , Técnicas In Vitro , Lectinas Tipo C , Datos de Secuencia Molecular , Neurocano , Fragmentos de Péptidos/aislamiento & purificación , Procesamiento Proteico-Postraduccional , Ratas , Ratas Sprague-Dawley
8.
Neurosci Res ; 16(4): 287-92, 1993 May.
Artículo en Inglés | MEDLINE | ID: mdl-8394556

RESUMEN

Glycosaminoglycans (GAGs) were isolated from the brains of reeler and normal mice on postnatal days 13 and 20. The GAG content of the reeler mouse brain, based upon the amount of DNA, was about 150% that of the normal mouse brain on both days. The GAGs consisted of chondroitin sulfate (CS), heparan sulfate (HS), hyaluronic acid (HA) and polysialosyl glycopeptides. There was no significant difference in the composition of GAGs isolated from either reeler or normal brain. Repeating disaccharide compositions of CS and HS were also similar in reeler and normal brains. Core proteins of brain chondroitin sulfate proteoglycans (CSPGs), solubilized with phosphate buffered saline, were prepared by digesting purified CSPGs with chondroitinase ABC, and were analyzed by SDS-polyacrylamide slab gel electrophoresis. There was no difference in the composition of core proteins from either reeler or normal brain. These results indicate that, although the GAG content of the reeler mouse brain is higher than the normal, all structural parameters of GAGs/CSPGs so far examined were normal. The rate of synthesis and/or degradation of brain GAGs may be affected in the mutant mouse brain.


Asunto(s)
Encéfalo/metabolismo , Glicosaminoglicanos/metabolismo , Ratones Mutantes Neurológicos/metabolismo , Animales , Proteoglicanos Tipo Condroitín Sulfato/química , Sulfatos de Condroitina/química , Cromatografía Líquida de Alta Presión , ADN/metabolismo , Disacáridos/química , Electroforesis en Gel de Poliacrilamida , Glicosaminoglicanos/química , Heparitina Sulfato/química , Ratones , Proteínas/análisis , Valores de Referencia , Solubilidad
9.
Neurosci Res ; 20(3): 195-207, 1994 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7838420

RESUMEN

The occurrence of multiple proteoglycan species is a characteristic of the brain. The structural features of individually characterized proteoglycans in the brain are first introduced in brief, then some examples are shown that suggest a relationship between multiple proteoglycans and the many distinct cell types and neural circuits in the brain. Typical experiments demonstrated the neuronal-activity-dependent expression of neural proteoglycans during the critical developmental period of some functional systems such as the visual and vibrissal barrel systems. In addition, the binding properties of neural proteoglycans to other cell surface molecules are discussed in conjunction with their involvement in cell-cell and cell-substratum interactions. This review also covers other potential functions of proteoglycans not only in the development and maintenance of the brain but also in the pathogenesis of Alzheimer's disease. Proteoglycans are really coming of age in neuroscience.


Asunto(s)
Química Encefálica/fisiología , Encéfalo/crecimiento & desarrollo , Proteoglicanos/metabolismo , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Animales , Encéfalo/citología , Humanos , Proteoglicanos/química
10.
Neurosci Res ; 32(4): 313-22, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9950058

RESUMEN

Neuroglycan C (NGC) is a 150 kDa transmembrane chondroitin sulfate proteoglycan with a 120 kDa core glycoprotein that was originally isolated from the developing rat brain. A rabbit antiserum, raised against a recombinant polypeptide representing a protein of the rat NGC core protein, recognized an NGC homolog in homogenates of brains of various vertebrates including humans. Because of the possible involvement of this proteoglycan in the etiology of a human neuronal disease, we cloned a complete coding sequence from a human brain cDNA library using a rat NGC cDNA as a probe. The predicted protein contains 539 amino acids and shows 86% homology with the rat counterpart. The domain structure characteristic of rat NGC was completely conserved in human NGC, which consisted of an N-terminal signal sequence, a chondroitin sulfate-attachment domain, an acidic amino acid cluster, an EGF-like domain, a transmembrane domain and a cytoplasmic tail. Northern blot analysis revealed that a single transcript of 2.4 kb was detectable in the brain, but not in other human tissues. By fluorescence in situ hybridization (FISH) analysis, the human NGC gene was assigned to the chromosomal 3p21.3 band, where the Sotos syndrome has been mapped. Involvement of the NGC gene in the etiology of the Sotos syndrome remains to be examined.


Asunto(s)
Proteoglicanos Tipo Condroitín Sulfato/genética , Cromosomas Humanos Par 3/genética , Secuencia de Aminoácidos , Animales , Enfermedades del Sistema Nervioso Central/genética , Corteza Cerebral , Embrión de Pollo , Mapeo Cromosómico/métodos , Humanos , Ratones , Datos de Secuencia Molecular , Conejos , Ratas
11.
Brain Res ; 790(1-2): 45-51, 1998 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-9593817

RESUMEN

Neurocan is a nervous tissue-unique chondroitin sulfate proteoglycan (CSPG) whose expression and proteolytic cleavage are developmentally regulated. In the adult rat brain, neurocan is completely cleaved into some proteoglycan fragments including the C-terminal half known as neurocan-C and a N-terminal fragment with a 130 kDa core glycoprotein (neurocan-130). We describe here the differential distribution of these two neurocan-derived CSPGs in the adult rat cerebrum and the occurrence of neurocan-130 as a new member of a perineuronal net-constituting molecule. At the light microscopic level, neurocan-130 exhibited pericellular localization around a subset of neurons in addition to diffuse distribution in the neuropil. In contrast, neurocan-C was distributed only diffusely in the neuropil. Double staining with anti-neurocan-130 and anti-synaptophysin antibodies suggested that neurocan-130 was localized in the vicinity of the synapses, but not at the synapses. Immunoelectron microscopy showed that neurocan-130 was mainly localized in the cytoplasm of glial cell processes, the so-called glial perineuronal net, encompassing the cell bodies of certain neurons. The presence of neurocan-130 in a limited number of glial cells may reflect some functional heterogeneity of the glia.


Asunto(s)
Química Encefálica/fisiología , Proteoglicanos Tipo Condroitín Sulfato/análisis , Proteoglicanos Tipo Condroitín Sulfato/química , Proteínas del Tejido Nervioso/análisis , Proteínas del Tejido Nervioso/química , Neuroglía/química , Neurópilo/química , Fragmentos de Péptidos/análisis , Factores de Edad , Animales , Corteza Cerebral/química , Corteza Cerebral/citología , Corteza Cerebral/crecimiento & desarrollo , Proteoglicanos Tipo Condroitín Sulfato/metabolismo , Hipocampo/química , Hipocampo/citología , Hipocampo/crecimiento & desarrollo , Lectinas Tipo C , Microscopía Inmunoelectrónica , Neostriado/química , Neostriado/citología , Neostriado/crecimiento & desarrollo , Proteínas del Tejido Nervioso/metabolismo , Neurocano , Neuroglía/ultraestructura , Neuronas/química , Neuronas/ultraestructura , Neurópilo/ultraestructura , Conejos , Ratas , Ratas Sprague-Dawley , Sinaptofisina/análisis
12.
Neurosci Lett ; 189(1): 25-8, 1995 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-7603617

RESUMEN

Alzheimer's beta-amyloid precursor related proteins bearing chondroitin sulfate chains were detected in the conditioned media of primary cultured astrocytes obtained from fetal rat brains by Western blotting using the monoclonal antibody 22C11 against Alzheimer's beta-amyloid precursor protein (APP), but not in the media of cortical neurons. The chondroitin sulfate proteoglycan form of APP was also detectable in a soluble proteoglycan fraction prepared from 10-day-old rat brains. However, the amount of proteoglycan form of APP in the brain was very small compared to non-proteoglycan forms at all the developmental stages from embryonic day 14 to 2 years. These observations suggest that astrocytes are one cellular source of the proteoglycan form of APP in the brain.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Astrocitos/metabolismo , Encéfalo/metabolismo , Sulfatos de Condroitina/metabolismo , Animales , Western Blotting , Encéfalo/citología , Células Cultivadas , Proteoglicanos Tipo Condroitín Sulfato/metabolismo , Ratas , Ratas Sprague-Dawley , Solubilidad
13.
Hear Res ; 110(1-2): 200-8, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9282902

RESUMEN

Chondroitin sulfate proteoglycans are present at high levels in the lower auditory system of mammals. Axon terminals on the principal neurons in the superior olivary nuclei contain chondroitin 4- and 6-sulfate, while the broad extracellular matrix around axon terminals contains chondroitin sulfate D, a highly sulfated chondroitin sulfate rich in the disaccharide unit of GlcA(2S)beta1 --> 3GalNAc(6S), in the dog. In the present study, we investigated the immunohistochemical staining of neurocan, a brain-specific proteoglycan, in the lower auditory tract of the dog, including an analysis by immunoelectron microscopy. Immunolocalization of neurocan was conspicuous in the medial and lateral superior olivary nuclei and much less intense immunostaining was seen in the cochlear nucleus and posterior colliculus. No immunoreactivity were found in other nuclei. The immunostaining in the medial and lateral superior olivary nuclei was observed as perineuronal nets around large principal neurons at the light-microscopic level, while no immunostaining was observed in the upper segment of the medial superior olivary nucleus and the medial segment of the lateral superior olivary nucleus, in which medium-sized and small neurons were located. Immunoelectron microscopy revealed the reaction products of immunostaining on cell membranes of the perikarya of principal neurons and on cell membranes of presynaptic terminals which made axo-somatic synapses on the principal cells. No immunoreactivity was detected at synaptic junctions, in the extracellular matrix or within axon terminals. In the cochlear nucleus, immunoreactive perineuronal nets were found around a small number of neurons and immunoreactive nerve fibers were scattered in the anterior ventral cochlear nucleus. In the posterior colliculus, perineuronal nets, which were weakly immunostained, were sparsely distributed in the central nucleus. These results suggest that different locations of chondroitin sulfate proteoglycans, including neurocan, may be associated with focal sites composed of neuronal surface, terminal boutons and extracellular matrix in the lower auditory tract of the adult dog.


Asunto(s)
Proteoglicanos Tipo Condroitín Sulfato/análisis , Núcleo Coclear/metabolismo , Proteínas del Tejido Nervioso/análisis , Núcleo Olivar/metabolismo , Animales , Sulfatos de Condroitina/metabolismo , Núcleo Coclear/ultraestructura , Perros , Femenino , Inmunohistoquímica , Lectinas Tipo C , Masculino , Microscopía Electrónica , Fibras Nerviosas , Neurocano , Neuronas/metabolismo , Neuronas/ultraestructura , Núcleo Olivar/ultraestructura
14.
J Pharm Sci ; 72(8): 948-51, 1983 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-6620156

RESUMEN

A GLC procedure has been developed for the determination of hydrazine in hydralazine and isoniazid drug raw materials, single and multicomponent tablets, injectables, and syrups. The method is based on the derivatization of hydrazine with benzaldehyde to form benzalazine. The minimum detectable amount of hydrazine in hydralazine and isoniazid raw materials and formulations is approximately 0.0003%. No hydrazine was found in the hydralazine raw material specimens examined. Traces of hydrazine (approximately 0.0003%) were found in some tablet lots and approximately 0.02% was found in an injectable product. A trace of hydrazine was found in one lot of isoniazid raw material and low levels (0.0012 and 0.0029%) were found in isoniazid tablet products. An isoniazid syrup contained approximately 0.2% hydrazine.


Asunto(s)
Hidralazina/análisis , Hidrazinas/análisis , Isoniazida/análisis , Química Farmacéutica , Cromatografía de Gases/métodos , Combinación de Medicamentos , Contaminación de Medicamentos , Almacenaje de Medicamentos , Soluciones/análisis , Comprimidos/análisis
15.
J Pharm Sci ; 67(7): 958-61, 1978 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-660515

RESUMEN

Three lots of meperidine hydrochloride, seven lots of meperidine tablets, and 41 lots of meperidine injectables were examined for impurities by TLC. Impurities found were ethyl 1-benzyl-4-phenyl-4-piperidinecarboxylate, methyl-4-piperidinecarboxylate, ethyl-4-phenyl-4-piperidinecarboxylate, and three unidentified compounds. Not all impurities were found in every lot of drug investigated, and none of the impurities exceeded a concentration of 1% of the meperidine present.


Asunto(s)
Meperidina/normas , Cromatografía en Capa Delgada , Contaminación de Medicamentos , Meperidina/análisis
16.
J Pharm Sci ; 69(4): 469-71, 1980 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7373550

RESUMEN

Two previously reported but unidentified phenylburazone degradation products were isolated from a tablet that was stored at 60 degrees for 203 days. The compounds, alpha-(N-phenylcarbamoyl)-N-caproylhydrazobenzene and alpha-hydroxy-alpha-(N-phenylcarbamoyl)-N-caproylhydrazobenzene, were isolated by chromatography, identified by mass and NMR spectrometry, and synthesized by the reaction of aniline with phenylbutazone or its hydroxy analog, respectively.


Asunto(s)
Fenilbutazona/análisis , Fenómenos Químicos , Química , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Fenilbutazona/normas , Comprimidos/normas
17.
J Pharm Sci ; 64(1): 125-7, 1975 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1133685

RESUMEN

The commonly used 4-aminoantipyrine dye formation procedure for hexachlorophene analysis in topical formulations was modified to overcome interference due to other components. Bar soaps and nonemulsion formulations are analyzed directly, employing a chloroform back-extraction stage of the dye prior to quantitation. Hexachlorophene in emulsions and liquid soaps is determined using a TLC separation prior to dye formation.


Asunto(s)
Hexaclorofeno/análisis , Amoníaco , Antipirina/análogos & derivados , Antipirina/análisis , Tampones (Química) , Cromatografía en Capa Delgada/métodos , Colorimetría/métodos , Emulsiones/análisis , Ferricianuros , Pomadas/análisis , Soluciones
18.
J Pharm Sci ; 64(9): 1545-7, 1975 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1185576

RESUMEN

Procedures for quantitating the lactam impurity, 7-chloro-1,3-dihydro-5-phenyl-2H-1,4-benzodiazepin-2-one 4-oxide, which can be present in chlordiazepoxide formulations, is presented. The method consists of trapping chlordiazepoxide in sulfuric acid in kieselguhr, eluting the impurity with ether, and quantitating by UV spectrophotometry in absolute alcohol at 312 nm.


Asunto(s)
Clordiazepóxido/análisis , Benzodiazepinonas/análisis , Cromatografía en Gel , Contaminación de Medicamentos , Lactamas/análisis
19.
J Pharm Sci ; 72(10): 1223-4, 1983 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6644580

RESUMEN

A high-performance liquid chromatographic method has been developed for the simultaneous determination of azobenzene and hydrazobenzene in phenylbutazone and sulfinpyrazone raw materials and formulations. The drug raw material or formulation is shaken with 1N NaOH and n-hexane and centrifuged. The n-hexane layer is injected into a chromatograph equipped with a 10-micron cyano-amino bonded phase column. Azobenzene and hydrazobenzene are detected at 313 and 254 nm, respectively; the sensitivities are approximately 1 and 2 ppm, respectively, in the raw materials and formulations.


Asunto(s)
Compuestos Azo/análisis , Fenilbutazona/análisis , Fenilhidrazinas/análisis , Sulfinpirazona/análisis , Cromatografía Líquida de Alta Presión/métodos , Contaminación de Medicamentos
20.
J Pharm Sci ; 74(1): 105-7, 1985 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3981407

RESUMEN

A GC procedure for the simultaneous determination of hydrazine and benzylhydrazine in isocarboxazid raw material and tablet formulations has been developed. The method is based on the reaction of benzoyltrifluoroacetone with hydrazine and benzylhydrazine to form the corresponding pyrazole derivatives. The minimum detectable amounts of hydrazine and benzylhydrazine in isocarboxazid are 0.002 and 0.02%, respectively.


Asunto(s)
Hidrazinas/análisis , Isocarboxazida/análisis , Cromatografía de Gases , Contaminación de Medicamentos , Comprimidos
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