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1.
Parasite Immunol ; 36(7): 303-12, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24749785

RESUMEN

Schistosoma mansoni is a blood fluke parasite responsible for schistosomiasis. The best long-term strategy to control schistosomiasis is through immunization combined with drug treatment. In this study, we cloned, expressed and purified SmTSP-2 fused to the N- and C-terminal halves of Sm29 and tested these chimeras as vaccine candidates using an adjuvant approved to be used in humans. The results demonstrated that vaccination with SmTSP-2 fused to N- or C-terminus of Sm29-induced reduction in worm burden and liver pathology when compared to control animals. Additionally, we detected high levels of mouse-specific IgG, IgG1 and IgG2a against both chimeras and significant amounts of IFN-γ and TNF-α and no IL-4. Finally, studies with sera from patients resistant to infection and living in schistosomiasis endemic areas revealed high levels of specific IgG to both chimeras when compared to healthy individuals. In conclusion, SmTSP-2/Sm29 chimeras tested here induced partial protection against infection and might be a potential vaccine candidate.


Asunto(s)
Antígenos Bacterianos/inmunología , Antígenos Helmínticos/inmunología , Proteínas Bacterianas/inmunología , Proteínas del Helminto/inmunología , Glicoproteínas de Membrana/inmunología , Schistosoma mansoni , Esquistosomiasis mansoni/inmunología , Esquistosomiasis mansoni/prevención & control , Tetraspaninas/inmunología , Vacunas/inmunología , Adyuvantes Inmunológicos/administración & dosificación , Animales , Anticuerpos Antihelmínticos/sangre , Antígenos Bacterianos/administración & dosificación , Antígenos Helmínticos/administración & dosificación , Proteínas Bacterianas/administración & dosificación , Islas de CpG , Citocinas/sangre , Femenino , Proteínas del Helminto/administración & dosificación , Humanos , Inmunoglobulina G/sangre , Hígado/patología , Glicoproteínas de Membrana/administración & dosificación , Ratones , Ratones Endogámicos C57BL , Oligodesoxirribonucleótidos/administración & dosificación , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/inmunología , Tetraspaninas/administración & dosificación , Vacunas/administración & dosificación
2.
Parasitology ; 140(3): 396-405, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23137846

RESUMEN

The factors that characterize Acanthamoeba strains as harmless or potentially pathogenic have not been elucidated. Analysing the in vitro and in vivo parameters of Acanthamoeba samples, including heat tolerance at temperatures close to that of the human body, cytopathic effects, and their ability to cause infections in animals, has been proposed to identify their pathogenic potential. Another promising criterion for differentiating strains is the analysis of their biochemical and immunochemical properties. In this study, a comparative evaluation between clinical and environmental Acanthamoeba isolates was performed on the basis of physiological, morphological, and immunochemical criteria. Crude antigens were used to characterize the protein profiles by electrophoresis and immunize mice to produce polyclonal and monoclonal antibodies. The antibodies were characterized using ELISA, Western blotting, and immunofluorescence techniques. The results obtained with polyclonal antibodies suggest the presence of specific proteins for each studied isolate and co-reactive immunochemical profiles among conserved components. Ten monoclonal antibody clones were obtained; mAb3 recognized 3 out of 4 samples studied. The results of this study may help standardize criteria for identifying and characterizing Acanthamoeba strains. Taken together, our results support the view that a set of features may help differentiate Acanthamoeba species and isolates.


Asunto(s)
Queratitis por Acanthamoeba/parasitología , Acanthamoeba/clasificación , Polvo/análisis , Parasitología/métodos , Acanthamoeba/inmunología , Acanthamoeba/aislamiento & purificación , Acanthamoeba/ultraestructura , Animales , Anticuerpos Monoclonales/biosíntesis , Anticuerpos Monoclonales/inmunología , Anticuerpos Antiprotozoarios/biosíntesis , Anticuerpos Antiprotozoarios/inmunología , Antígenos de Protozoos/administración & dosificación , Antígenos de Protozoos/inmunología , Antígenos de Protozoos/aislamiento & purificación , Western Blotting , Electroforesis , Ensayo de Inmunoadsorción Enzimática/métodos , Composición Familiar , Técnica del Anticuerpo Fluorescente , Humanos , Inmunización , Ratones , Ratones Endogámicos BALB C , Microscopía Electrónica de Rastreo , Proteínas Protozoarias/química , Proteínas Protozoarias/inmunología , Especificidad de la Especie
3.
Acta Trop ; 204: 105356, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32001249

RESUMEN

Sequence databases on Schistosoma mansoni have revealed micro-exon gene (MEGs) families. Many of these genes are highly expressed in parasite life cycle stages associated with the mammalian host infection and appear to be involved in immune evasion by schistosomes. So, we believe that MEG-coding proteins would make potential candidates for vaccine development or diagnosis for schistosomiasis. Here, we study MEG-3.2 and MEG-3.4, members of the MEG-3 family. Recombinant (r) proteins were produced and formulated with Freund's adjuvant for vaccination of mice. Immunization with recombinant MEG-3.2 or MEG-3.4 formulation generated high levels of IgG1 antibodies. Additionally, vaccination also induced a mixed Th1/Th2/Th17-type of response, since IFN-γ, IL-5 and IL-17 cytokines were detected in the supernatant of spleen cell cultures; however it failed to induce reduction in parasitic worm burden. Finally, the recombinant proteins were evaluated in a serological assay using human samples. Schistosome-infected individuals showed higher levels of both IgG and IgM against rMEG-3.2 compared to non-infected individuals, while only IgM anti-rMEG-3.4 antibodies were elevated in infected patients. Therefore, between both studied molecules, MEG-3.2 protein is the antigen that shows potential to compose a serological diagnosis test for schistosomiasis.


Asunto(s)
Antígenos Helmínticos/inmunología , Schistosoma mansoni/inmunología , Esquistosomiasis mansoni/prevención & control , Animales , Modelos Animales de Enfermedad , Femenino , Ratones , Ratones Endogámicos C57BL , Esquistosomiasis mansoni/sangre , Esquistosomiasis mansoni/diagnóstico , Vacunación
4.
J Med Genet ; 43(1): 91-6, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16033918

RESUMEN

BACKGROUND: An inherited germline P53 mutation has been identified in cases of childhood adrenocortical carcinoma (ACT), a neoplasm with a high incidence in southern Brazil. The penetrance of ACT in carriers of the point mutation, which encodes an arginine-to-histidine substitution at codon 337 of TP53 (R337H), has not been determined. OBJECTIVE: To investigate the penetrance of childhood ACT in carriers of the R337H TP53 mutation. METHODS: The family histories of 30 kindreds of 41 southern Brazilian children with ACT were obtained. A PCR based assay was used to detect this P53 mutation in a large number of relatives of children with ACT. In all, 927 individuals were tested for the mutation, 232 from the non-carrier and 695 (including the 40 probands) from the carrier parental lines. RESULTS: 40 children with ACT carried the TP53 R337H mutation; the remaining child with ACT was not tested. There was no evidence of Li-Fraumeni syndrome in any of the kindreds; however, seven met the criteria for Li-Fraumeni-like syndrome. The carrier parental line was identified in each kindred. Of the 695 individuals tested in the carrier parental line, 240 (34.5%) were positive for the mutation, while none of the 232 individuals in the other parental line carried the mutation. The penetrance of ACT was 9.9% (95% confidence interval, 8.7% to 11.1%). CONCLUSIONS: The TP53 R337H mutation dramatically increases predisposition to childhood ACT but not to other cancers, and explains the increased frequency of ACT observed in this geographic region.


Asunto(s)
Neoplasias de la Corteza Suprarrenal/genética , Predisposición Genética a la Enfermedad , Mutación de Línea Germinal/genética , Penetrancia , Proteína p53 Supresora de Tumor/genética , Distribución por Edad , Niño , Preescolar , Femenino , Genotipo , Humanos , Lactante , Masculino , Linaje , Factores de Riesgo
5.
Hum Mutat ; 18(6): 547, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11748852

RESUMEN

X-linked adrenal hypoplasia congenita (AHC) is caused by mutations in the NR0B1 gene. This gene encodes an orphan member of the nuclear receptor superfamily, DAX1. Ongoing efforts in our laboratory have identified nine novel NR0B1 mutations in X-linked AHC patients (Y81X, 343delG, 457delT, 629delG, L295P, 926-927delTG, 1130delA, 1141-1155del15, and E428X). Two additional families segregate previously identified NR0B1 mutations (501delA and R425T). Sequence analysis of the mitochondrial D-loop indicates that the 501delA family is unrelated through matrilineal descent to our previously analyzed 501delA family.


Asunto(s)
Insuficiencia Suprarrenal/genética , Proteínas de Unión al ADN/genética , Receptores de Ácido Retinoico/genética , Proteínas Represoras , Factores de Transcripción/genética , Insuficiencia Suprarrenal/congénito , Codón sin Sentido , Receptor Nuclear Huérfano DAX-1 , ADN/química , ADN/genética , Análisis Mutacional de ADN , Mutación del Sistema de Lectura , Humanos , Mutación , Mutación Missense , Eliminación de Secuencia
6.
J Clin Endocrinol Metab ; 84(3): 1116-21, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10084604

RESUMEN

Although several genes have been investigated in adrenal tumorigenesis, the genetic background of adrenocortical tumors (ACT) remains poorly characterized. In southern Brazil, the annual incidence of ACT is unusually high, ranging from 3.4-4.2/million children, compared with a worldwide incidence of 0.3/million children younger than 15 yr. Environmental factors have been implicated because the distribution of these tumors follows a regional, rather than a familial, pattern. However, decreased penetrance of a particular gene defect cannot be excluded. Because linkage or other traditional genetic analyses would not be appropriate to investigate the defect(s) associated with ACT in this population, we used comparative genomic hybridization (CGH) to screen for DNA sequence copy number changes in 9 nonfamilial ACT (6 carcinomas and 3 adenomas) from unrelated patients from this region. Six female (aged 10 months to 6 3/4 yr) and 3 male (1 1/12 to 3 1/4 yr) patients were studied. Three carcinomas were at stage I, 1 was at stage II, and another was at stage III. Two carcinomas had evidence of invasion of the vena cava, and 3 were more than 3 cm in size. All patients underwent surgical excision of their tumors; chemotherapy was administered to cancer patients. Currently, all patients are alive and in remission, with the exception of 1 patient with stage III cancer. High mol wt DNA was extracted from tumor tissue obtained at surgery and frozen at -70 C. This DNA was labeled and used for CGH according to standard procedures. Digital image analysis was performed to detect chromosomal gains or losses. CGH evaluation revealed extensive genetic aberrations in both adenomas and carcinomas; there were no significant differences relative to age, gender, size, or stage of the tumor (P > 0.1). Chromosomes and chromosomal regions 1q, 5p, 5q, 6p, 6q, 8p, 8q, 9q, 10p, 11q, 12q, 13q, 14q, 15q, 16, 18q, 19, and 20q demonstrated gains, whereas 2q, 3, 4, 9p, 11, 13q, 18, 20p, and Xq showed losses. The most striking finding was consistent copy number gain of chromosomal region 9q34 in 8 of the 9 tumors. We conclude that both benign and malignant ACT from southern Brazil show multiple genetic aberrations, including a consistent gain of chromosomal region 9q34. This genomic area may harbor genetic defects that predispose to ACT formation and are shared by the patients who were investigated in this study or are accumulated epigenetically under the influence of a common factor, such as an environmental mutagen.


Asunto(s)
Neoplasias de la Corteza Suprarrenal/genética , Brasil , Preescolar , Aberraciones Cromosómicas/genética , Cromosomas Humanos Par 12/genética , Cromosomas Humanos Par 4/genética , Cromosomas Humanos Par 9/genética , Femenino , Dosificación de Gen , Humanos , Lactante , Masculino , Hibridación de Ácido Nucleico
7.
Neuroscience ; 68(1): 29-45, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7477932

RESUMEN

A loss of target-derived neurotrophic factors is hypothesized to be one of the major determinants of central nervous system neuronal degeneration. In order to obtain further insight into early neuronal responses to injury, lesion-induced alterations in the expression of high- and low-affinity nerve growth factor receptors, as well as growth-associated phosphoprotein-43 genes in nucleus basalis magnocellularis, thalamic and neocortical neurons were studied. For this purpose, unilateral cortical devascularization operations were conducted on adult rats. Animals received i.c.v. infusions of vehicle or nerve growth factor (12 micrograms/day) and were killed at one, three, seven and 15 days post-lesion. In situ hybridization studies using 35S-labelled oligonucleotide probes for p75NGFR, p140trk and growth-associated phosphoprotein-43 messenger RNAs reveals that these genes were differentially regulated following the lesion. In the nucleus basalis magnocellularis ipsilateral to the lesion, p140trk gene expression significantly decreased on days 3 and 7, while p75NGFR messenger RNA initially increased on day 3 and decreased on days 7 and 15 after lesion. GAP-43 messenger RNA levels were significantly increased in the nucleus basalis magnocellularis on post-lesion days 3 and 7. Moreover, in contrast to p75NGFR or 140trk, growth-associated phosphoprotein-43 messenger RNA levels were significantly increased in pyramidal neurons located in the remaining cortex adjacent to the cortical lesion at all time points. In the lateral and ventroposterior nuclei of the thalamus, growth-associated phosphoprotein-43 messenger RNA level was slightly increased on days 1 and 3 and was dramatically decreased, significantly below the levels in sham-operated controls, on post-lesion days 7 and 15. During nerve growth factor application, the level of p140trk messenger RNA in the lesioned nucleus basalis magnocellularis returned to values observed in the contralateral nucleus basalis magnocellularis while p75NGFR messenger RNA was increased above values noted in all animals not treated with nerve growth factor. Nerve growth factor treatment did not affect the expression of growth-associated phosphoprotein-43 messenger RNA in any of the areas studied. p140trk messenger RNA was not up-regulated during the time that nerve growth factor was applied, as observed for p75NGFR, but only eight days after interrupting nerve growth factor treatment. Three cell types, nucleus basalis magnocellularis, cortical pyramidal and thalamic neurons, were probably affected in different ways by the devascularization with respect to lesion extent. Consequently, the remaining number of synaptic contacts in each of these brain areas is most likely different which may lead to a differential regulation of growth-associated phosphoprotein-43 messenger RNA.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Infarto Cerebral/metabolismo , Glicoproteínas de Membrana/biosíntesis , Factores de Crecimiento Nervioso/farmacología , Proteínas del Tejido Nervioso/biosíntesis , Proteínas Tirosina Quinasas Receptoras/biosíntesis , Receptores de Factor de Crecimiento Nervioso/biosíntesis , Animales , Ganglios Basales/efectos de los fármacos , Ganglios Basales/metabolismo , Secuencia de Bases , Química Encefálica/efectos de los fármacos , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/metabolismo , Proteína GAP-43 , Inmunohistoquímica , Hibridación in Situ , Masculino , Glicoproteínas de Membrana/genética , Datos de Secuencia Molecular , Proteínas del Tejido Nervioso/genética , ARN Mensajero/biosíntesis , Ratas , Ratas Wistar , Proteínas Tirosina Quinasas Receptoras/genética , Receptor de Factor de Crecimiento Nervioso , Receptores de Factor de Crecimiento Nervioso/genética , Tinción con Nitrato de Plata , Tálamo/efectos de los fármacos , Tálamo/metabolismo
8.
Neuroscience ; 56(4): 955-63, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7506821

RESUMEN

The ability of acidic fibroblast growth factor to elicit a trophic response in the nervous system of the rat was tested in vitro and in vivo. Treatment of cultured septal cells with acidic fibroblast growth factor resulted in an elongation of glial processes as assessed by immunostaining for glial fibrillary acidic protein. Increased choline acetyltransferase was also observed. The responses to acidic fibroblast growth factor in vivo were studied in rats trained in a spatial memory task, using the Morris water maze. Randomly selected animals were subjected to unilateral cortical devascularization. This lesion results in partial unilateral infarction of the neocortex, and in retrograde degeneration of the nucleus basalis magnocellularis. Animals were tested post-lesion for memory retention and were then killed for morphological studies. Intracerebroventricular administration of acidic fibroblast growth factor (0.6 microgram/h for seven days starting at surgery) prevented the lesion-induced impairment in this test, and reduced the nucleus basalis magnocellularis cholinergic degeneration, as assessed by morphometric choline acetyltransferase-like immunoreactivity and radioenzymatic assay for choline acetyltransferase activity. The preservation of the phenotype of injured cholinergic neurons of the nucleus basalis magnocellularis by acidic fibroblast growth factor was indicated by the maintenance of the cross-sectional area of cell bodies and mean length of neuritic processes one month after surgery. The effect of acidic fibroblast growth factor in non-cholinergic cells remains to be investigated. It is suggested that acidic fibroblast growth factor may alleviate the lesion-induced deficit in the memory retention task by preventing disruption of functional connections between nucleus basalis magnocellularis and intact cortical areas.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Infarto Cerebral/fisiopatología , Colina O-Acetiltransferasa/biosíntesis , Factor 1 de Crecimiento de Fibroblastos/farmacología , Memoria/fisiología , Proteínas del Tejido Nervioso/biosíntesis , Neuronas/efectos de los fármacos , Conducta Espacial , Sustancia Innominada/efectos de los fármacos , Animales , Células Cultivadas , Infarto Cerebral/tratamiento farmacológico , Fibras Colinérgicas/efectos de los fármacos , Fibras Colinérgicas/fisiología , Factor 1 de Crecimiento de Fibroblastos/uso terapéutico , Masculino , Recuerdo Mental/fisiología , Desempeño Psicomotor/efectos de los fármacos , Desempeño Psicomotor/fisiología , Ratas , Degeneración Retrógrada , Sustancia Innominada/fisiopatología
9.
Brain Res Mol Brain Res ; 33(1): 1-6, 1995 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8774940

RESUMEN

Recently we reported that human recombinant acidic fibroblast growth factor (aFGF) is capable of preventing degeneration of nucleus basalis magnocellularis neurons in vivo and inducing growth of astrocytes in vitro. In the present study, the effects of aFGF on the concentration of nerve growth factor (NGF) and its messenger RNA were investigated in the rat cerebral cortex following unilateral cortical infarction. Lesioned animals exhibited a significant increase of NGF in the remaining cortex ipsilateral to the lesion. After combining cortical lesion with intracerebroventricular application of aFGF (12 micrograms/day for 7 days), we observed an 8-fold increase in the NGF concentration and a marked increase in the level of steady state NGF mRNA relative to controls ipsilaterally, and a less pronounced aFGF effect in the contralateral cerebral cortex. These results support the hypothesis that the neurotrophic effects previously shown for aFGF and basic FGF (bFGF) in neurotrophin-sensitive neurons is mediated by inducing increased production of NGF within the injured central nervous system (CNS) of adult animals.


Asunto(s)
Corteza Cerebral/efectos de los fármacos , Infarto Cerebral/tratamiento farmacológico , Factor 1 de Crecimiento de Fibroblastos/uso terapéutico , Factores de Crecimiento Nervioso/genética , Fármacos Neuroprotectores/uso terapéutico , Animales , Secuencia de Bases , Corteza Cerebral/metabolismo , Infarto Cerebral/metabolismo , Inyecciones Intraventriculares , Masculino , Datos de Secuencia Molecular , Factores de Crecimiento Nervioso/biosíntesis , Ratas , Ratas Wistar
10.
Brain Res Mol Brain Res ; 17(3-4): 258-68, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7685463

RESUMEN

The intensity of p75NGFR receptor-like immunoreactivity and the mRNAs encoding p75NGFR, T alpha 1 alpha-tubulin, GAP-43 and the myelin proteins MBP and PLP were measured in the developing cerebellum to study the effects of perinatal thyroid hormone imbalance in rats. Results compared to age-matched controls provide in vivo evidence for differential gene regulation by thyroid hormone in the developing cerebellum. We found that p75NGFR immunoreactivity was strikingly elevated in hypothyroid rats, whereas p75NGFR mRNA content remained only twice as high as that of control levels on postnatal day 15 (P15). When p75NGFR immunoreactivity was still elevated in hypothyroid rats, Purkinje cells exhibited proximal axonal varicosities, axonal twisting and differences in axonal caliber. The mRNAs encoding proteins involved with neurite growth-promoting elements, T alpha 1 alpha-tubulin and GAP-43, were also increased in hypothyroidism, possibly reflecting a neuronal response to a deficiency in, or damage to, cerebellar neurons, or a general delay in their down regulation. Similar increases were not observed for the myelin specific genes. MBP and PLP mRNAs were first detected on P2 of hyperthyroid rats, and they increased with age. Hypo- or hyperthyroidism did not affect the initial onset of MBP and PLP expression, however, hyperthyroidism increased levels of PLP and MBP mRNAs between P2 and P10. By contrast, the most consistent decrease in MBP and PLP mRNAs in rats with thyroid hormone deficiency was observed only on P10. At later times (P15 and P30), the two mRNA levels were similar to controls in all groups. These results are consistent with a role for thyroid hormone in the earlier stages of cerebellar myelination. Hypothryoidism led to specific increases in T alpha 1 alpha-tubulin and GAP-43 mRNAs, and in the immunoreactivity and mRNA levels of p75NGFR receptor--all changes that may play a role in the observed abnormal neuronal outgrowth.


Asunto(s)
Animales Recién Nacidos/genética , Cerebelo/crecimiento & desarrollo , Expresión Génica , Hipertiroidismo/genética , Hipotiroidismo/genética , Proteína Proteolipídica de la Mielina , ARN Mensajero/genética , Receptores de Factor de Crecimiento Nervioso/análisis , Animales , Apoproteínas/genética , Proteína GAP-43 , Código Genético , Sustancias de Crecimiento/genética , Masculino , Glicoproteínas de Membrana/genética , Proteína Básica de Mielina/genética , Proteínas de la Mielina/genética , Proteínas del Tejido Nervioso/genética , Células de Purkinje/ultraestructura , Ratas , Ratas Wistar , Receptores de Factor de Crecimiento Nervioso/genética , Tubulina (Proteína)/genética
11.
J Chem Neuroanat ; 12(1): 15-27, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9001945

RESUMEN

We have tested the hypotheses that nerve growth factor treatment in adult post-hypothyroid rats can: (1) restore cross-sectional area of cholinergic cells of the nucleus basalis and (2) prevent further atrophy of these neurons following cortical infarction. In addition, we assessed the expression of p75NGFR and p140trkA mRNAs in the nucleus basalis cells of post-hypothyroid rats. Rats were rendered hypothyroid by the addition of propylthiouracil to their diet beginning on embryonic day 19 until the age of 1 month. At this time both the pups and their dams continued to receive 0.05% propylthiouracil in their diet and the pups were thyroidectomized. At 60 days, propylthiouracil treatment was interrupted and thyroxine levels were restored to normal by daily subcutaneous administration of physiological levels of thyroxine. Morphometric analysis identified atrophied nucleus basalis magnocellularis cholinergic cells at two ages, days 75 and 105, identified by in situ hybridization for p75NGFR and p140trkA mRNAs in methylene blue stained cells (day 75) and choline acetyltransferase immunostaining (day 105). The mean number of silver grains (pixels) per microns2 (mean +/- S.E.M.) of cell body cross-sectional area for p75NGFR mRNA in the nucleus basalis magnocellularis of euthyroid rats was 3.43 +/- 0.89, which was not statistically different from post-hypothyroid animals (4.02 +/- 1.07). A similar finding was noted for p140trkA mRNA: mean number of grains in the euthyroid group was 5.54 +/- 0.96 and was not statistically different from the post-hypothyroid group (6.32 +/- 1.45). Nerve growth factor treatment in adulthood (between days 75 and 82) did not restore cross-sectional area from early thyroid deprivation. However, it prevented further atrophy of nucleus basalis magnocellularis neurons following cortical devascularization inflicted in adulthood (day 75).


Asunto(s)
Acetilcolina/fisiología , Infarto Cerebral/patología , Hipotiroidismo/patología , Factores de Crecimiento Nervioso/farmacología , Neuronas/efectos de los fármacos , Sustancia Innominada/efectos de los fármacos , Animales , Atrofia/prevención & control , Tamaño de la Célula , Infarto Cerebral/complicaciones , Infarto Cerebral/metabolismo , Ventrículos Cerebrales , Hipotiroidismo/complicaciones , Hipotiroidismo/metabolismo , Infusiones Parenterales , Masculino , Neuronas/metabolismo , Neuronas/patología , Proteínas Proto-Oncogénicas/genética , ARN Mensajero/biosíntesis , Ratas , Ratas Wistar , Proteínas Tirosina Quinasas Receptoras/genética , Receptor de Factor de Crecimiento Nervioso , Receptor trkA , Receptores de Factor de Crecimiento Nervioso/genética , Sustancia Innominada/metabolismo , Sustancia Innominada/patología
12.
Neuroreport ; 5(9): 1105-9, 1994 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-8080966

RESUMEN

Quantitative analysis of ChAT immunoreactive neurones was used to evaluate the protective potential of BDNF or NT-3 against retrograde changes in nucleus basalis magnocellularis (nbm) cholinergic neurones after unilateral partial devascularization of the rat neocortex. A daily intracerebroventricular dose of 12 micrograms, proven to be effective for NGF and aFGF in the same experimental paradigm, was administered by minipump infusion for a 1-week period. Thirty days after lesioning, neuronal shrinkage and loss of neuritic processes were not prevented by treatment. The results indicate that intracerebroventricularly delivered BDNF and NT-3 are not as effective as NGF and aFGF in protection of nbm cholinergic neurones against lesion-induced changes in adult rat brain.


Asunto(s)
Ganglios Basales/citología , Factores de Crecimiento Nervioso/farmacología , Proteínas del Tejido Nervioso/farmacología , Neuronas/efectos de los fármacos , Sistema Nervioso Parasimpático/citología , Animales , Vías Autónomas/citología , Vías Autónomas/efectos de los fármacos , Ganglios Basales/efectos de los fármacos , Factor Neurotrófico Derivado del Encéfalo , Corteza Cerebral/irrigación sanguínea , Circulación Cerebrovascular/fisiología , Colina O-Acetiltransferasa/inmunología , Colina O-Acetiltransferasa/metabolismo , Inmunohistoquímica , Inyecciones Intraventriculares , Masculino , Factores de Crecimiento Nervioso/administración & dosificación , Proteínas del Tejido Nervioso/administración & dosificación , Neuritas/efectos de los fármacos , Neurotrofina 3 , Sistema Nervioso Parasimpático/efectos de los fármacos , Ratas , Ratas Wistar
13.
Brain Res Dev Brain Res ; 72(2): 237-44, 1993 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-8485846

RESUMEN

Deficits or excesses of thyroid hormones during critical periods of mammalian cerebellar development can lead to profound biochemical and morphological abnormalities in this system. The goal of this study was to investigate the effects of perinatal hypo- and hyperthyroidism on the ontogeny of nerve growth factor (NGF) and its low-affinity receptor (p75NGFR) in the rat cerebellum. The concentration of NGF and of p75NGFR immunoreactivity (IR) were measured, several days after birth, in cerebella of rats which had received propylthiouracil (PTU) or thyroxine. NGF concentration was markedly enhanced only on postnatal day 2 (P2) in hyperthyroid rats, whereas in hypothyroid (PTU-treated) rats NGF values were similar to age-matched controls. These observations suggest that thyroid hormone affects NGF synthesis during early periods of cerebellar development. In Purkinje cells of control animals, p75NGFR IR peaked at P10. In hypothyroid rats, the expression of p75NGFR was retarded, peaking at P15, whereas in hyperthyroid rats it was advanced, peaking at P8. The increased p75NGFR IR found in Purkinje cell bodies and the delayed disappearance of p75NGFR IR from the external granular layer of hypothyroid rats suggest different roles for thyroid hormone in the developing cerebellum. We conclude that p75NGFR and NGF are independently regulated by thyroid hormone during critical periods of cerebellar development. The effect of thyroid hormone deficiency on p75NGFR content in Purkinje cells may involve complex mechanisms such as impaired efficiency of axonal transport.


Asunto(s)
Animales Recién Nacidos/metabolismo , Cerebelo/metabolismo , Hipertiroidismo/metabolismo , Hipotiroidismo/metabolismo , Factores de Crecimiento Nervioso/metabolismo , Receptores de Factor de Crecimiento Nervioso/metabolismo , Animales , Animales Recién Nacidos/crecimiento & desarrollo , Conducta Animal , Cerebelo/crecimiento & desarrollo , Hipertiroidismo/psicología , Hipotiroidismo/psicología , Inmunohistoquímica , Masculino , Concentración Osmolar , Ratas , Valores de Referencia
14.
Braz J Med Biol Res ; 17(2): 107-17, 1984.
Artículo en Inglés | MEDLINE | ID: mdl-6518334

RESUMEN

The present review focuses on some aspects of the function of catechol-O-methyl-transferase (COMT) in the hypothalamic control of gonadotrophin release by the pituitary gland. The in situ influence of a catecholestrogen (2 OH.E2) on the amount of COMT in the hypothalamic nuclei involved in such control as well as on the process of sexual differentiation of the brain is also discussed. Catecholestrogens do not play a significant role in the induction of sexual differentiation and the observed action is probably a pharmacological one. It is difficult to understand why a substance whose structure is so closely related to that of estrogen is so much less active. Most probably the estrogen receptor in the cytosol at this stage of development is not able to recognize the catecholestrogen. Since catecholestrogens are not true virilizing substances they may be used to assess the critical levels of enzymes which are required to determine the sexual pattern of hypothalamic activity. The fact that the extent of the changes in COMT content of the hypothalamus is related to the amount of hormone used to induce virilization strengthens the view that sexual differentiation is the consequence of a genomic change during the critical period, which will induce an enzymatic pattern characteristic of the male acyclic pattern of gonadotrophin control. The finding that the COMT content of the hippocampus also changes in parallel to sexual differentiation leads us to speculate that perhaps sexual behavior may also be differentiated in the same way.


Asunto(s)
Catecol O-Metiltransferasa/metabolismo , Gonadotropinas/metabolismo , Hipotálamo/enzimología , Diferenciación Sexual , Animales , Dopamina/metabolismo , Estrógenos/efectos adversos , Femenino , Infertilidad Femenina/inducido químicamente , Hormona Luteinizante/metabolismo , Masculino , Ovario/efectos de los fármacos , Ratas , Factores Sexuales , Testosterona/metabolismo
15.
Braz J Med Biol Res ; 22(8): 1001-4, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2633840

RESUMEN

We report the diuretic, natriuretic and kaliuretic effects of dexamethasone (DEXA) on intact and adrenalectomized (ADX) male Wistar rats. Indomethacin (INDO) and spironolactone were used to evaluate the involvement of prostaglandin and mineralocorticoid receptors in these actions. DEXA (400 micrograms/kg) and INDO (20 mg/kg) were injected iv and spironolactone (8 mg/100 g) was administered by the oral route. The parameters analyzed were urinary volume (UV), sodium excretion (UNaV) and potassium excretion (UKV). DEXA increased UV and UKV in both intact and ADX rats. INDO administered to intact rats reduced UV by 28% (P less than 0.05) and caused anuresis in ADX rats, but did not interfere with the increased UV induced by DEXA in either ADX or intact animals. Spironolactone did not interfere with diuretic parameters in control animals, but in DEXA-treated animals it decreased UKV by 30% and inhibited DEXA-induced diuresis. These data rule out the possibility of prostaglandin involvement in the acute effects of DEXA and suggest that DEXA induces diuresis through its action on mineralocorticoid receptors or on specific receptors for glucocorticoid (the type II receptor). The latter might also be inhibited by spironolactone.


Asunto(s)
Dexametasona/uso terapéutico , Diuresis/efectos de los fármacos , Indometacina/farmacología , Natriuresis/efectos de los fármacos , Potasio/orina , Espironolactona/farmacología , Adrenalectomía , Animales , Masculino , Prostaglandinas E/orina , Ratas , Ratas Endogámicas
16.
Braz J Med Biol Res ; 33(10): 1217-24, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11004723

RESUMEN

Adrenocortical tumors (ACT) in children under 15 years of age exhibit some clinical and biological features distinct from ACT in adults. Cell proliferation, hypertrophy and cell death in adrenal cortex during the last months of gestation and the immediate postnatal period seem to be critical for the origin of ACT in children. Studies with large numbers of patients with childhood ACT have indicated a median age at diagnosis of about 4 years. In our institution, the median age was 3 years and 5 months, while the median age for first signs and symptoms was 2 years and 5 months (N = 72). Using the comparative genomic hybridization technique, we have reported a high frequency of 9q34 amplification in adenomas and carcinomas. This finding has been confirmed more recently by investigators in England. The lower socioeconomic status, the distinctive ethnic groups and all the regional differences in Southern Brazil in relation to patients in England indicate that these differences are not important to determine 9q34 amplification. Candidate amplified genes mapped to this locus are currently being investigated and Southern blot results obtained so far have discarded amplification of the abl oncogene. Amplification of 9q34 has not been found to be related to tumor size, staging, or malignant histopathological features, nor does it seem to be responsible for the higher incidence of ACT observed in Southern Brazil, but could be related to an ACT from embryonic origin.


Asunto(s)
Adenoma/genética , Neoplasias de la Corteza Suprarrenal/genética , Carcinoma/genética , Cromosomas Humanos Par 9/genética , Amplificación de Genes , Adenoma/epidemiología , Adenoma/etnología , Neoplasias de la Corteza Suprarrenal/epidemiología , Neoplasias de la Corteza Suprarrenal/etnología , Carcinoma/epidemiología , Carcinoma/etnología , Preescolar , Contaminación Ambiental/efectos adversos , Humanos , Incidencia , Masculino , Mutación , Clase Social
17.
Braz J Med Biol Res ; 33(10): 1225-34, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11004724

RESUMEN

Childhood adrenocortical tumors (ACT) are rare. In the USA, only about 25 new cases occur each year. In Southern Brazil, however, approximately 10 times that many cases are diagnosed each year. Most cases occur in the contiguous states of São Paulo and Paraná. The cause of this higher rate has not been identified. Familial genetic predisposition to cancer (p53 mutations) and selected genetic syndromes (Beckwith-Wiedemann syndrome) have been associated with childhood ACT in general but not with the Brazilian counterpart. Most of the affected children are young girls with classic endocrine syndromes (virilizing and/or Cushing). Levels of urinary 17-ketosteroids and plasma dehydroepiandrosterone sulfate (DHEA-S), which are abnormal in approximately 90% of the cases, provide the pivotal clue to a diagnosis of ACT. Typical imaging findings of pediatric ACT consist of a large, well-defined suprarenal tumor containing calcifications with a thin capsule and central necrosis or hemorrhage. The pathologic classification of pediatric ACT is troublesome. Even an experienced pathologist can find it difficult to differentiate carcinoma from adenoma. Surgery is the single most important procedure in the successful treatment of ACT. The role of chemotherapy in the management of childhood ACT has not been established although occasional tumors are responsive to mitotane or cisplatin-containing regimens. Because of the heterogeneity and rarity of the disease, prognostic factors have been difficult to establish in pediatric ACT. Patients with incomplete tumor resection or with metastatic disease at diagnosis have a dismal prognosis. In patients with localized and completely resected tumors, the size of the tumor has predictive value. Patients with large tumors have a much higher relapse rate than those with small tumors.


Asunto(s)
Adenoma , Neoplasias de la Corteza Suprarrenal , Carcinoma , Adenoma/diagnóstico , Adenoma/epidemiología , Adenoma/genética , Adenoma/terapia , Adolescente , Neoplasias de la Corteza Suprarrenal/diagnóstico , Neoplasias de la Corteza Suprarrenal/epidemiología , Neoplasias de la Corteza Suprarrenal/genética , Neoplasias de la Corteza Suprarrenal/terapia , Adulto , Carcinoma/diagnóstico , Carcinoma/epidemiología , Carcinoma/terapia , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Pronóstico
18.
Clin Genet ; 65(3): 183-90, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-14756668

RESUMEN

A 14-year-old female presented to the Pediatric Endocrine Clinic, Universidade Federal o Parana Curitiba, Brazil, for obesity. A few years later, despite normal breast development, the patient had failed to menstruate and lacked pubic and axillary hair. Laboratory analyses revealed high levels of testosterone. Karyotype analysis was XY. Direct sequencing of her genomic DNA showed a G to T transition at nucleotide 2089 at exon 2 in the androgen receptor gene, resulting in a substitution of Phe for Cys at position 576. This mutation disrupts the first Zn finger critical to DNA binding and transcriptional activity and results in complete androgen-insensitivity syndrome (CAIS). This individual was part of 700-member multigenerational kindred of German origin living in small villages in Southern Brazil. Family members who gave informed consent were screened using a polymerase chain reaction-based method. Nineteen CAIS-affected individuals and carriers were identified. All presented with infertility and lack of or sparse pubic hair. The prevalence of common AIS within the kindred greatly exceeds that of the general population and is due in part to their isolated familial and community structures. All individuals are genuinely feminine in their appearance, sex behavior, gender identity, and integration within their communities. We conclude that CAIS leads to complete feminization of XY individuals and results in individuals who are psychologically and socially established and integrated as women within the familial and cultural contexts of their communities.


Asunto(s)
Identidad de Género , Receptores Androgénicos/genética , Adolescente , Síndrome de Resistencia Androgénica/diagnóstico , Síndrome de Resistencia Androgénica/etnología , Síndrome de Resistencia Androgénica/genética , Brasil/epidemiología , Análisis Mutacional de ADN , Salud de la Familia/etnología , Femenino , Alemania/etnología , Humanos , Masculino , Linaje , Fenotipo , Mutación Puntual
19.
Braz. j. med. biol. res ; 33(10): 1217-24, Oct. 2000. ilus
Artículo en Inglés | LILACS | ID: lil-270219

RESUMEN

Adrenocortical tumors (ACT) in children under 15 years of age exhibit some clinical and biological features distinct from ACT in adults. Cell proliferation, hypertrophy and cell death in adrenal cortex during the last months of gestation and the immediate postnatal period seem to be critical for the origin of ACT in children. Studies with large numbers of patients with childhood ACT have indicated a median age at diagnosis of about 4 years. In our institution, the median age was 3 years and 5 months, while the median age for first signs and symptoms was 2 years and 5 months (N = 72). Using the comparative genomic hybridization technique, we have reported a high frequency of 9q34 amplification in adenomas and carcinomas. This finding has been confirmed more recently by investigators in England. The lower socioeconomic status, the distinctive ethnic groups and all the regional differences in Southern Brazil in relation to patients in England indicate that these differences are not important to determine 9q34 amplification. Candidate amplified genes mapped to this locus are currently being investigated and Southern blot results obtained so far have discarded amplification of the abl oncogene. Amplification of 9q34 has not been found to be related to tumor size, staging, or malignant histopathological features, nor does it seem to be responsible for the higher incidence of ACT observed in Southern Brazil, but could be related to an ACT from embryonic origin.


Asunto(s)
Humanos , Masculino , Preescolar , Adenoma/genética , Neoplasias de la Corteza Suprarrenal/genética , Carcinoma/genética , Cromosomas Humanos Par 9/genética , Amplificación de Genes , Adenoma/epidemiología , Adenoma/etnología , Neoplasias de la Corteza Suprarrenal/epidemiología , Neoplasias de la Corteza Suprarrenal/etnología , Carcinoma/epidemiología , Carcinoma/etnología , Contaminación Ambiental/efectos adversos , Incidencia , Mutación , Clase Social
20.
Braz. j. med. biol. res ; 33(10): 1225-34, Oct. 2000. tab
Artículo en Inglés | LILACS | ID: lil-270220

RESUMEN

Childhood adrenocortical tumors (ACT) are rare. In the USA, only about 25 new cases occur each year. In Southern Brazil, however, approximately 10 times that many cases are diagnosed each year. Most cases occur in the contiguous states of Sao Paulo and Paraná. The cause of this higher rate has not been identified. Familial genetic predisposition to cancer (p53 mutations) and selected genetic syndromes (Beckwith-Wiedemann syndrome) have been associated with childhood ACT in general but not with the Brazilian counterpart. Most of the affected children are young girls with classic endocrine syndromes (virilizing and/or Cushing). Levels of urinary 17-ketosteroids and plasma dehydroepiandrosterone sulfate (DHEA-S), which are abnormal in approximately 90 percent of the cases, provide the pivotal clue to a diagnosis of ACT. Typical imaging findings of pediatric ACT consist of a large, well-defined suprarenal tumor containing calcifications with a thin capsule and central necrosis or hemorrhage. The pathologic classification of pediatric ACT is troublesome. Even an experienced pathologist can find it difficult to differentiate carcinoma from adenoma. Surgery is the single most important procedure in the successful treatment of ACT. The role of chemotherapy in the management of childhood ACT has not been established although occasional tumors are responsive to mitotane or cisplatin-containing regimens. Because of the heterogeneity and rarity of the disease, prognostic factors have been difficult to establish in pediatric ACT. Patients with incomplete tumor resection or with metastatic disease at diagnosis have a dismal prognosis. In patients with localized and completely resected tumors, the size of the tumor has predictive value. Patients with large tumors have a much higher relapse rate than those with small tumors.


Asunto(s)
Humanos , Masculino , Femenino , Recién Nacido , Lactante , Preescolar , Niño , Adolescente , Adulto , Adenoma/fisiopatología , Neoplasias de la Corteza Suprarrenal/fisiopatología , Carcinoma/fisiopatología , Adenoma/diagnóstico , Adenoma/terapia , Neoplasias de la Corteza Suprarrenal/diagnóstico , Neoplasias de la Corteza Suprarrenal/terapia , Carcinoma/diagnóstico , Carcinoma/terapia , Pronóstico
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