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1.
Vis Neurosci ; 18(1): 43-54, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11347815

RESUMO

Nitric oxide (NO) is a neuronal messenger molecule that mediates pathway refinement in some brain regions. We used nicotinamide adenine dinucleotide phosphate diaphorase (NADPHd) histochemistry to examine the development of NO expression in the superior colliculus (SC) of kittens aged E28-E58 and P2-P57 and adults in order to determine if NO expression is correlated with pathway refinement. At E28, labeled cells were seen only within the subventricular zone (SVZ). At E36-E41, labeled cells were also found within the deep gray layer (DGL) of SC. At E51 and E58, a few labeled neurons were also present in the intermediate gray layer (IGL). These neurons already had extensive dendritic fields and well-developed morphologies at the time that they first expressed nitric oxide synthase (NOS). The number of neurons labeled in the DGL and IGL increased postnatally, reaching a peak density between P14 and P35. Neurons within the optic (OL) and superficial gray layers (SGL) were first visible at P7 and increased slightly in number until adulthood. However, SGL-labeled neurons were relatively limited in number and lightly labeled at all ages examined. We conclude that (1) NADPHd expression occurs in SC beginning in the second trimester in kittens and progresses in a ventral to dorsal pattern between E36-P35; (2) few neurons in kitten SGL are labeled by NADPHd and these appear relatively late in postnatal development; and (3) there is no correlation between NOS expression and retinocollicular pathway refinement in kittens, a result different from that seen in rodents.


Assuntos
NADPH Desidrogenase/metabolismo , Óxido Nítrico/biossíntese , Colículos Superiores/embriologia , Colículos Superiores/metabolismo , Animais , Gatos , Feminino , Histocitoquímica , Fibras Nervosas/metabolismo , Plasticidade Neuronal , Óxido Nítrico Sintase/biossíntese , Óxido Nítrico Sintase Tipo I , Gravidez , Córtex Visual/metabolismo
2.
J Radiol ; 81(8): 888-90, 2000 Aug.
Artigo em Francês | MEDLINE | ID: mdl-10916008

RESUMO

We report the case of a patient with infrarenal abdominal aortic aneurysm with mural thrombus covering the ostium of a patent inferior mesenteric artery (IMA). The IMA was supplied via flow from an accessory aneurysmal lumen within the mural thrombus that filled retrogradely from the aorta. This unusual pattern, associated with calcifications within the thrombus, raised the possibility of chronic aortic dissection.


Assuntos
Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aortografia , Artéria Mesentérica Inferior/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Idoso , Aneurisma da Aorta Abdominal/patologia , Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular , Feminino , Humanos , Ligadura , Artéria Mesentérica Inferior/patologia , Artéria Mesentérica Inferior/cirurgia , Trombose/patologia , Trombose/cirurgia
3.
J Chem Neuroanat ; 18(4): 147-59, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10781733

RESUMO

Nitric oxide and acetylcholine are important neuromodulators implicated in brain plasticity and disease. We have examined the cellular and fiber localization of nitric oxide in the cat superior colliculus (SC) and its degree of co-localization with ACh using nicotinamide adenine dinucleotide phosphate diaphorase (NADPHd) histochemistry and an antibody to neuronal nitric oxide synthase. ACh was localized using an antibody against choline acetyltransferase. We also made injections of biocytin into the region of the parabrachial brainstem to confirm that this region is a source of nitric oxide containing fibers in SC. NADPHd labeled neurons within the superficial layers of the superior colliculus included pyriform, vertical fusiform, and horizontal morphologies. Labeled neurons in the intermediate gray layer were small to medium in size, and mostly of stellate morphology. Neurons in the deepest layers had mostly vertical or stellate morphologies. NADPHd labeled fibers formed dense patches of terminal boutons within the intermediate gray layer and streams of fibers within the deepest layers of SC. Choline acetyltransferase antibody labeling in adjacent sections indicated that many fibers must contain both labels. Over 94% of neurons in the pedunculopontine tegmental and lateral dorsal tegmental nuclei were also labeled by both NADPHd and choline acetyltransferase. In addition, biocytin labeled fibers from this region were localized in the NADPHd labeled patches. We conclude that nitric oxide is contained in a variety of cell types in SC and that both nitric oxide and ACh likely serve as co-modulators in this midbrain structure.


Assuntos
Colina O-Acetiltransferase/análise , Óxido Nítrico Sintase/análise , Colículos Superiores/enzimologia , Animais , Gatos , Lisina/análogos & derivados , NADPH Desidrogenase/análise , Fibras Nervosas/enzimologia , Neurônios/enzimologia , Neurônios/ultraestrutura , Óxido Nítrico Sintase Tipo I , Ponte/citologia , Ponte/enzimologia , Terminações Pré-Sinápticas/enzimologia , Colículos Superiores/citologia
4.
Eur J Pediatr Surg ; 10(6): 390-4, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11215782

RESUMO

We describe two cases of giant-cell fibroblastoma (GCF) with dermato fibro sarcoma protuberans (DFSP) component, occurring in two children in a chest wall localization. One case recurred 1 year later. The two patients were tumor-free 12 and 8 years later. GCF is a rare mesenchymal cutaneous and subcutaneous tumor reported mostly in the first two decades of life. Dermato fibro sarcoma protuberans, occurring preferentially in adults, is a rare skin tumor with a pronounced tendency to local recurrence. Some cases of association of recurrence of GFC under the form of DFSP have been reported, raising the question of a continuum between the two tumors. The treatment of choice of the two tumors is a wide local excision.


Assuntos
Dermatofibrossarcoma/cirurgia , Fibroma/cirurgia , Neoplasias Primárias Múltiplas/cirurgia , Neoplasias Cutâneas/cirurgia , Transformação Celular Neoplásica/patologia , Criança , Pré-Escolar , Dermatofibrossarcoma/patologia , Procedimentos Cirúrgicos Dermatológicos , Feminino , Fibroma/patologia , Humanos , Masculino , Neoplasias Primárias Múltiplas/patologia , Reoperação , Pele/patologia , Neoplasias Cutâneas/patologia , Retalhos Cirúrgicos
5.
Brain Res Dev Brain Res ; 118(1-2): 217-20, 1999 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-10611522

RESUMO

Nitric oxide (NO) has been shown to mediate refinement of glutamatergic axonal pathways during development. In this study, we investigated whether the development of a cholinergic pathway in the intermediate gray layer (IGL) of the mouse superior colliculus (SC) is also mediated by NO. The pathway was labeled using an antibody directed against choline acetyltransferase (ChAT) and its distribution examined in normal C57/BL6 mice and in knockout mice in which the genes for the neuronal isoform of nitric oxide synthase (NOS) or both the endothelial and neuronal isoforms of NOS had been disrupted. We also examined the development of expression of NOS using nicotinamide adenine dinucleotide phosphate diaphorase (NADPHd) staining. NADPHd labeled cells were found within the IGL by P8 and formed loose clusters of cells by P12-P15. ChAT and NADPHd labeled fibers were first observed at P12 and gradually established their characteristic two-tiered patchy pattern between P14 and P21. Comparison of the ChAT labeled fiber distribution in normal, single nNOS and double e,nNOS knockout mice revealed no differences between these three groups. We therefore conclude that nitric oxide does not mediate refinement of this cholinergic pathway.


Assuntos
Fibras Colinérgicas/fisiologia , Óxido Nítrico Sintase/deficiência , Colículos Superiores/crescimento & desenvolvimento , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Animais Recém-Nascidos/metabolismo , Colina O-Acetiltransferase/metabolismo , Fibras Colinérgicas/enzimologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout/genética , NADPH Desidrogenase/metabolismo , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase Tipo I , Óxido Nítrico Sintase Tipo II , Óxido Nítrico Sintase Tipo III , Colículos Superiores/enzimologia
6.
Prog Brain Res ; 118: 37-50, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9932433

RESUMO

We have produced a digital atlas of the distribution of nitric oxide synthase (NOS) in the mouse brain as a reference source for our studies on the roles of nitric oxide in brain development and plasticity. NOS was labeled using nicotinamide adenine dinucleotide phosphate diaphorase (NADPHd) histochemistry. In addition, choline acetyltransferase (ChAT) immunocytochemistry was used to identify cholinergic cells because many of the NADPHd positive cells were thought to colocalize acetylcholine. Some sections were also labeled with antibodies to either the neuronal (nNOS) or endothelial (eNOS) isoforms of NOS. Series of sections from 11 C57/BL6 mice were collected and labeled for NADPHd and/or ChAT. We collected two types of data from this material: color digital photographs illustrating the density of cell and fiber labeling, and computer/microscope plots of the locations of all the labeled cells in selected sections. The data can be viewed as either a series of single-section maps produced by combining the plots with the digital images, or as 3-D views derived from the cell plots. The atlas of labeled cell maps, together with selected color photographs and 3-D views, is available for viewing via the World Wide Web (http:@nadph.anatomy.lsumc.edu). Examination of the atlas data has revealed several points about the distribution of NOS throughout the mouse brain. Firstly, different populations of NADPHd-positive neurons can be distinguished by different patterns of staining. In some brain areas neurons are intensely stained by the NADPHd technique where label fills the cell bodies and much of the dendritic trees. In other brain regions labeling is much lighter, is principally confined to the cytoplasm of the cell soma, and extends only a short distance within proximal dendrites. Intense labeling is typical of neurons in the caudate/putamen and mesopontine tegmental nuclei. Most of the labeled neurons in the cortex also stain this way. Lighter, "granular" label is found in many other nuclei, including the medial septum, hippocampus, and cerebellum. In addition to staining pattern, we have also noted that different subpopulations of NOS-neurons can be distinguished on the basis of colocalization with ChAT. Substantial overlap of the distributions of these two substances was observed although very little colocalization was found in most cholinergic cell groups except the mesopontine tegmental nuclei. Other points of interest arising from this project include the apparent lack of NADPHd labeling in the CA1 pyramidal cells of the hippocampus or the Purkinje neurons in the cerebellum. This observation is especially relevant given that synaptic plasticity in these regions is reported to be nitric-oxide dependent.


Assuntos
Mapeamento Encefálico , Encéfalo/enzimologia , Bases de Dados Factuais , Internet , Óxido Nítrico Sintase/metabolismo , Animais , Colina O-Acetiltransferase/metabolismo , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo I , Especificidade de Órgãos
7.
Prog Brain Res ; 118: 133-52, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9932439

RESUMO

Nitric oxide (NO) has been implicated as a retrograde signal in the process of refining axonal pathways during brain development. To determine some of the factors involved in this process, we have used two model pathway systems in the rat and mouse superior colliculus (SC). The first, the patch-cluster system, consists of clusters of neurons in the intermediate gray layer (igl) which transiently express NO during development and which receive input from a cholinergic pathway from the parabrachial brainstem as well as from other pathways containing different transmitters. The second system, the retinocollicular pathway, consists of glutamatergic fibers that project to the superficial gray layer. We have used both nitric oxide synthase inhibition (nw-nitro-L-arginine, NoArg) and single (nNOS) and double (nNOS and eNOS) gene knockout mice to examine the effect that reduction in NOS has upon the development of these two systems. The onset of NOS expression in rat, as revealed by nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) labeling, occurred in igl cells as early as postnatal day P5, with clusters being well-established by P14. Cholinergic fibers were first visible at P10 and formed obvious patches and tiers by P14. Intraperitoneal injections of NoArg from P1-P22 had no effect upon the development of these cholinergic patches. The pathway also developed normally in both single and double-knockout mice. In contrast, the ipsilateral retinocollicular pathway was altered in the double, but not in the single knockout mouse. This pathway is exuberant during the first week of life, being distributed across much of the mediolateral axis of the rostral SC. By P8-P15, this pathway has retracted to the most mediorostral SC. This refinement was delayed substantially in the double NOS gene knockout mouse. Ipsilateral fibers were found within 3-5 separate medio-lateral patches within the rostral 600 microns of SC at P15, and patches of abnormal size and extent were also seen at P18. We conclude from these results that NO plays a role in pathway development in the rodent SC, but only in glutamatergic pathways and only when both endothelial and neuronal forms of NOS have been deleted. The mechanism of this effect must involve pathway elimination in situations where there is non-correlated electrical activity. It is likely that NO promotes fiber retraction rather than fiber stabilization in these developing nerve fibers.


Assuntos
Óxido Nítrico/fisiologia , Retina/fisiologia , Colículos Superiores/crescimento & desenvolvimento , Vias Visuais/crescimento & desenvolvimento , Acetilcolina/metabolismo , Envelhecimento , Animais , Fibras Colinérgicas/fisiologia , Lateralidade Funcional , Camundongos , Camundongos Knockout , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase/fisiologia , Óxido Nítrico Sintase Tipo I , Ratos , Transdução de Sinais/fisiologia , Colículos Superiores/metabolismo , Vias Visuais/metabolismo
8.
Dev Neurosci ; 19(3): 260-73, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9208210

RESUMO

Nitric oxide may serve as a retrograde messenger to refine or stabilize synapses in the developing nervous system. Whether this action is dependent upon glutamate and the N-methyl-D-aspartate receptor is not yet established. We have used the patch-cluster system in the intermediate gray layer (IGL) of the rat superior colliculus (SC), a system receiving both glutamatergic and cholinergic input, to study this question. The normal distribution and development of nitric oxide synthase (NOS) in SC was examined using nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) histochemistry in Sprague-Dawley rats aged P4 to adulthood. Fibers containing acetylcholine (ACh) were identified using choline acetyltransferase (ChAT) immunocytochemistry. In addition, N omega-nitro-L-arginine, an inhibitor of NOS, was injected intraperitoneally from birth until P10, P14, P18, or P21-22 to determine if NOS inhibition would disrupt the formation of the ACh patches. Control animals were studied from the same age groups. Our results show NADPH-d-labeled cells within the periaqueductal gray and the deep gray layer of SC by P4, the earliest age examined. By P8-P9, cells in the IGL were well labeled by NADPH-d, while few in the superficial layers (SL) were labeled. SL cells were visible by P10 and were intensely labeled by P14. IGL cells transiently expressed NADPH-d in that the number of labeled cells increased from P8 to P35, then decreased in the adult. ChAT-labeled fibers first appeared in the IGL at P10, formed a characteristic two-tier pattern by P14, and established obvious patches by P21. Inhibition of NOS from birth produced no qualitative differences in the distribution or density of either ChAT-labeled fibers or NADPH-d-labeled cells and fibers at any of the ages examined. We therefore conclude that NO does not contribute to the refinement of cholinergic fiber patches in the rat SC, probably because the fiber system is not glutamatergic.


Assuntos
Fibras Colinérgicas/fisiologia , Inibidores Enzimáticos/farmacologia , Proteínas do Tecido Nervoso/antagonistas & inibidores , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico/fisiologia , Nitroarginina/farmacologia , Ratos/anatomia & histologia , Colículos Superiores/efeitos dos fármacos , Animais , Biomarcadores , Gatos , Colina O-Acetiltransferase/análise , Di-Hidrolipoamida Desidrogenase/análise , Proteínas do Tecido Nervoso/análise , Proteínas do Tecido Nervoso/fisiologia , Plasticidade Neuronal , Óxido Nítrico Sintase/fisiologia , Ratos Sprague-Dawley , Especificidade da Espécie , Colículos Superiores/enzimologia , Colículos Superiores/crescimento & desenvolvimento , Colículos Superiores/patologia
9.
J Pediatr Orthop B ; 6(1): 33-41, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9039665

RESUMO

The clinical features of seven children with myositis ossificans (circumscripta and progressiva) and radiographic signs of the disease are described. We recommend systematic radiological examination to seek other skeletal malformations for congenital hallux valgus in young children, for it may be the first sign of a myositis ossificans progressiva. The "zone phenomenon" observed on histology, along with differential diagnosis and evolution, is documented. The necessity of a biopsy and different forms of treatment are discussed.


Assuntos
Miosite Ossificante , Adolescente , Criança , Pré-Escolar , Feminino , Hallux Valgus/diagnóstico , Humanos , Recém-Nascido , Masculino , Músculo Esquelético , Miosite Ossificante/diagnóstico , Tomografia Computadorizada por Raios X
10.
Vis Neurosci ; 14(6): 1167-73, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9447696

RESUMO

We examined the pattern of NADPH-diaphorase (NADPH-d) staining in the lateral geniculate nucleus (LGN) of dorsal thalamus in fetal and newborn kittens, and adult cats. This staining visualizes the synthesizing enzyme of nitric oxide (NO), a neuromodulator associated with central nervous system (CNS) development and synaptic plasticity. In the adult, very few LGN cells stained for NADPH-d, and these were restricted to interlaminar zones and ventral C layers. NADPH-d labeled a dense network of fibers and axon terminals throughout the LGN and adjacent thalamic nuclei. The source of such labelling has been reported to be cholinergic neurons from the parabrachial region of the brain stem (Bickford et al., 1993). A very different pattern of staining was observed in prenatal and early postnatal kittens. Between embryonic (E) day 46-57, lightly stained cells appeared throughout the LGN. From this age, through about the first month of life, the number of stained cells in the LGN rose rapidly. The density (cells/mm2) of labeled cells peaked at postnatal day (P) 28 (P28), and was about 150 times greater than the level measured in the adult LGN. After P28, cell staining declined rapidly, and fell to adult levels at P41. The reduction in cell staining that occurred between P35-41 was accompanied by the appearance of fine-caliber fiber staining, similar to that observed in the adult LGN. NADPH-d staining, which reveals the presence of nitric oxide synthase (NOS), and thus NO activity, may reflect two processes. In the adult LGN, the labeling of cholinergic axons arising from the brain-stem parabrachial region coupled with a paucity of the LGN cellular staining suggests that NO operates in an orthograde manner, being co-released with ACh to influence the gain and efficacy of retinogeniculate transmission. By contrast, in developing kitten, NADPH-d staining of LGN cells suggests that NO acts in a retrograde fashion, perhaps playing a role in maintaining associative processes underlying activity-dependent refinement of retinogeniculate connections.


Assuntos
Envelhecimento/metabolismo , Animais Recém-Nascidos/metabolismo , Feto/metabolismo , Corpos Geniculados/enzimologia , NADPH Desidrogenase/metabolismo , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Gatos , Desenvolvimento Embrionário e Fetal/fisiologia , Corpos Geniculados/embriologia , Corpos Geniculados/crescimento & desenvolvimento , Coloração e Rotulagem
11.
Prenat Diagn ; 16(12): 1156-9, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8994254

RESUMO

A case of false-negative discrepancy between results of chorionic villi (direct preparation) and those of fetal tissue with an isochromosome 18q [i(18q)] in amniotic cells and fetal blood is reported. Fluorescence in situ hybridization (FISH) confirmed this uncommon chromosomal rearrangement. The fetus showed cyclopia and multiple congenital anomalies which have never been reported in cases of i(18q).


Assuntos
Cromossomos Humanos Par 18 , Isocromossomos , Cariotipagem , Diagnóstico Pré-Natal , Anormalidades Múltiplas/diagnóstico por imagem , Anormalidades Múltiplas/genética , Adulto , Amniocentese , Amostra da Vilosidade Coriônica , Feminino , Humanos , Gravidez , Ultrassonografia Pré-Natal
12.
Bull Cancer ; 83(10): 877-81, 1996 Oct.
Artigo em Francês | MEDLINE | ID: mdl-8952639

RESUMO

Pulmonary blastoma is a rare malignant tumor. A new case is reported in a 3 years 6 month-old girl. An apparent clinical remission was first obtained after a surgical treatment followed by a conventional chemotherapy during six months. Afterwards the persistence of a microscopic residual pulmonary disease lead us to deliver successfully an intensive chemotherapy followed by autologous peripheral blood stem cells reinjection. The child remains disease free 12 months after graft. Problems set by the histogenesis of this tumor, its unspecific clinical and paraclinical features and the role of conventional and intensive chemotherapy followed by autologous bone marrow transplantation are discussed on the basis of a review of 50 cases in the literature.


Assuntos
Neoplasias Pulmonares/diagnóstico , Blastoma Pulmonar/diagnóstico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimioterapia Adjuvante , Pré-Escolar , Terapia Combinada , Feminino , Transplante de Células-Tronco Hematopoéticas , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/terapia , Pneumonectomia , Prognóstico , Blastoma Pulmonar/patologia , Blastoma Pulmonar/terapia , Reoperação , Resultado do Tratamento
14.
Prog Brain Res ; 108: 313-32, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8979811

RESUMO

Neurons within the superior colliculus (SC) contain a variety of neurochemicals, including the amino acid neurotransmitters GABA and glutamate, the calcium binding proteins calbindin and parvalbumin, and the neuromodulator nitric oxide. We have examined the development of expression of these substances using antibody immunocytochemistry. These results are summarized in Fig. 10. GABA and calbindin are expressed very early in development, at a time when cells are still dividing and migrating from the subventricular zone. The expression of both GABA and CB is maximal at around E40-46, the age at which these cells have just established their adult lamination and extrinsic afferents have begun to grow into the tectum. GABA and CB likely play diverse roles during this stage of development, including the regulation of intracellular calcium during cell migration and neurite outgrowth. Glutamate is expressed somewhat later in development while parvalbumin immunoreactivity does not appear until shortly after birth. These two substances continue to increase in density throughout the period of postnatal growth, at a time when synapse formation and evoked electrical activity are beginning to develop. Both PV and glutamate may be involved in one or both of these activity-dependent processes. Nitric oxide synthase (NOS) is expressed at different times in different cell groups. NOS appears very early in prenatal development in cells within the SVZ and in the deep gray layer of SC. On the other hands, cells within the intermediate gray layer of SC do not express NOS until shortly before birth. The igl cells that express NOS at this age are clustered neurons similar to those that project to the CFR in the adult. NOS expression occurs in these cells at precisely the time when axons begin to form patches that innervate these clusters. Based upon this temporal correlation, we hypothesize that nitric oxide may regulate synapse formation in this cell group.


Assuntos
Proteínas de Ligação ao Cálcio/biossíntese , Neurotransmissores/biossíntese , Óxido Nítrico Sintase/biossíntese , Colículos Superiores/metabolismo , Animais , Gatos , Desenvolvimento Embrionário e Fetal/fisiologia , Colículos Superiores/embriologia , Colículos Superiores/crescimento & desenvolvimento
15.
Acta Neuropathol ; 91(4): 400-8, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8928617

RESUMO

CD24 is a glycoprotein with an unusual structure consisting of a small protein core extensively glycosylated and linked to the outer surface of the plasma membrane by a glycosylphosphatidylinositol (GPI) lipid anchor. Its murine homolog mCD24 is transiently expressed during the development and differentiation of the hematopoietic and neural cell lineages. We have searched for the expression of CD24 in the developing and in the mature human brain as well as in a wide range of neuroectodermal tumors. Neuroblastomas, a subgroup of tumors able to maturate from undifferentiated features towards mature ganglioneuromas, were more extensively studied. Immunohistochemical studies demonstrated that CD24 is transiently expressed by neurons during human brain development. In neuroectodermal tumors, CD24 is a marker of neuronal tumors. Furthermore, in neuroblastomas, CD24 expression decreases as tumors differentiate. In non-neuronal neuroectodermal tumors, CD24 expression is mostly absent. When present, it correlates with the emergence of anaplastic histological features. Reverse transcriptase -polymerase chain reaction (RT-PCR) demonstrated the presence of an unique transcript identical in both hematopoietic, developing and tumoral nervous tissue. RT-PCR and in situ hydridization techniques showed that CD24 expression is transcriptionally regulated. Interestingly, Western blot analysis demonstrated differential CD24 isoforms according to the tissue (hematopoietic versus nervous), the differentiation status, and the origin of neuroblastomas likely reflecting variations in the extent of glycosylation. This indicates an additional level of regulation of CD24 involving post-translational modifications.


Assuntos
Neoplasias do Sistema Nervoso Central/metabolismo , Glicosilfosfatidilinositóis/metabolismo , Adulto , Neoplasias Encefálicas/metabolismo , Pré-Escolar , Humanos , Imuno-Histoquímica , Hibridização In Situ , Lactente , Neoplasias Neuroepiteliomatosas/metabolismo , Células Tumorais Cultivadas
16.
Pediatr Pathol Lab Med ; 16(1): 25-40, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8963629

RESUMO

A collaborative study was performed to determine the different types and mechanisms of intestinal abnormalities during gestation. Cases had to fulfill one or more of the following three criteria: (1) meconium ileus, (2) intestinal stenosis or atresia, and (3) meconium peritonitis. Esophageal atresia, anorectal atresia, and abdominal wall defects were excluded. One hundred two cases were reviewed from the autopsies of 42 induced abortions, 22 stillborns, and the surgical findings in 38 neonates. Meconium ileus was detected mainly during the second trimester (28/38), and was associated with cystic fibrosis (15), fetal blood deglutition (4), infection (6), or multiple-abnormalities (10), in which three chromosomal aberrations were found. Intestinal stenosis or atresia was more commonly detected during the third trimester of gestation (46/56). Sixteen of the 30 duodenal malformations were associated with trisomy 21, whereas in the 26 small intestinal atresias, signs of distress or ischemia were most frequently detected. Only 8 of 25 meconium peritonitis cases were isolated. A total of 20 cystic fibrosis cases could be proved. In this series, functional abnormalities were observed predominantly in the second trimester and associated mainly with cystic fibrosis or amniotic fluid abnormalities. Anatomic lesions were commonly detected later on and associated with ischemic conditions, chromosomal aberrations, and even cystic fibrosis.


Assuntos
Doenças Fetais/patologia , Atresia Intestinal/patologia , Obstrução Intestinal/patologia , Mecônio , Constrição Patológica/diagnóstico , Constrição Patológica/embriologia , Constrição Patológica/patologia , Fibrose Cística/diagnóstico , Fibrose Cística/embriologia , Fibrose Cística/patologia , Feminino , Doenças Fetais/diagnóstico , Humanos , Recém-Nascido , Atresia Intestinal/diagnóstico , Atresia Intestinal/embriologia , Obstrução Intestinal/diagnóstico , Obstrução Intestinal/embriologia , Peritonite/diagnóstico , Peritonite/embriologia , Peritonite/patologia , Gravidez
17.
Graefes Arch Clin Exp Ophthalmol ; 233(12): 756-65, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8626083

RESUMO

BACKGROUND: The fetal face is clearly seen by ultrasonography: we considered measurement of certain orbitofacial parameters of interest in the human fetus in order to establish norms for facial development. METHODS: We included 108 "normal" fetuses ranging in age from 16.5 to 41 weeks of amenorrhea. The orbitofacial parameters studied were outer canthal distance, inner canthal distance, oropalpebral distance right side and left side, and palpebral fissure length side and left side. The ocular parameters studied were corneal horizontal diameter and axial length. The traditional anthropometric parameters of the fetus were determined by pathological examination: age, weight head circumference and height. A statistical study analyzed the different correlations and established linear regression equations for orbitofacial parameters as a function of age. Polynomial regression models were tested to the third degree as a function of age and the head circumference/II ratio. RESULTS: Results are given in six different age groups. We find excellent correlation between the different parameters. Statistically valid linear regression equations were established for orbitofacial parameters. Polynomial regression equations were compared to linear equations their correlation coefficient and standard error, but showed no greater validity. Skull growth is more rapid than facial growth, which itself is more rapid vertically than horizontally. CONCLUSION: This study establishes norms for the different orbitofacial parameters, in particular the oropalpebral distance, for which we found no bibliographic references. The general interest of these measures lies in the description of malformation syndromes.


Assuntos
Antropometria , Face/embriologia , Desenvolvimento Embrionário e Fetal , Face/diagnóstico por imagem , Feminino , Feto/fisiologia , Idade Gestacional , Humanos , Masculino , Gravidez , Análise de Regressão , Ultrassonografia Pré-Natal
18.
Arch Pediatr ; 2(6): 545-7, 1995 Jun.
Artigo em Francês | MEDLINE | ID: mdl-7640755

RESUMO

BACKGROUND: Melanotic neuroectodermal tumor is a mostly benign tumor, rare in childhood, essentially located in the head and neck region. CASE REPORT: A two-month-old girl was seen for a rapidly increasing odontogenic tumor which appeared cystic at the CT scan. After enucleation, this premaxillar tumor recurred one month later with an osteogenic aspect at the CT scan. Urine catecholamine excretion was normal; Methyl Iodo Benzyl Guanidin scintigraphy failed to show any fixation and electron microscopy examination of the biopsy showed several varieties of melanocytes. A partial maxillectomy was performed by oral approach. The patient is well 4 1/2 years later. CONCLUSION: This observation confirms the recurrence potential of this tumor and the cosmetic interest of the oral surgical approach.


Assuntos
Neoplasias Maxilares , Tumor Neuroectodérmico Melanótico , Feminino , Humanos , Lactente , Neoplasias Maxilares/diagnóstico , Neoplasias Maxilares/patologia , Neoplasias Maxilares/cirurgia , Tumor Neuroectodérmico Melanótico/diagnóstico , Tumor Neuroectodérmico Melanótico/patologia , Tumor Neuroectodérmico Melanótico/cirurgia
19.
Fetal Diagn Ther ; 9(5): 310-20, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7818779

RESUMO

In this geographically based study the findings on 158 abnormal fetuses, primarily diagnosed by routine antenatal ultrasound, are correlated with the results of the examinations subsequently carried out by a fetopathologist and a clinical geneticist. Ninety fetuses (57%) had a single malformation, 66 were polymalformed (42%) and 2 had no malformations. In 90% of all these cases, the prenatally and postnatally detected anomalies were identical; in 3% the defect established at necropsy was different from that diagnosed prenatally, and in 7% the predicted anomaly was absent. These values did not depend on whether single or multiple malformations were involved. In 57% of the polymalformed cases, however, the ultrasound examination missed at least one other diagnosable anomaly. On the basis of pathological and clinical genetic expertise, a risk of recurrence of the anomaly was revised in 13% of the single malformed cases and in 53% of the multiple ones, i.e., in 30% of all the cases of malformation on average. This study confirms the need for the fetus to be examined by a pathologist and a clinical geneticist after termination of a not 'at risk' pregnancy in order to check the accuracy of the sonographic procedure, to confirm the reasons for terminating the pregnancy to the parents, and to be able to monitor the next pregnancy based on an accurate assessment of the risk of recurrence.


Assuntos
Aborto Induzido , Anormalidades Congênitas/diagnóstico por imagem , Ultrassonografia Pré-Natal , Anormalidades Múltiplas , Reações Falso-Positivas , Feminino , França , Humanos , Cariotipagem , Gravidez , Fatores de Risco
20.
Arterioscler Thromb ; 14(9): 1393-8, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8068598

RESUMO

Cardiovascular disease is the major cause of mortality in renal transplant recipients. Plasma levels of low-density lipoprotein cholesterol (LDL-C) are often elevated following renal transplantation, and the immunosuppressant cyclosporin A has been implicated as a predisposing factor for posttransplantation hyperlipidemia. Lipoprotein(a) [Lp(a)] is an LDL-like lipoprotein particle; elevated levels of Lp(a) provide an independent and significant risk factor for cardiovascular disease. Plasma concentrations of Lp(a) vary greatly among individuals, and the mechanisms that govern changes in their levels in transplant patients are unknown. The effect(s) of cyclosporin A on Lp(a) was studied in two groups of renal transplantation patients. In group I plasma lipoproteins including Lp(a) were measured before and after successful renal transplantation; this group received both prednisone and cyclosporin A for immunosuppression. Group II patients were studied after renal transplantation and received prednisone alone for immunosuppression. Following surgery, group I patients demonstrated increased plasma concentrations of LDL-C (mean +/- SEM range, 111 +/- 6 to 142 +/- 17 mg/dL; P < .005). In contrast, plasma Lp(a) levels for this group were markedly decreased after renal transplantation (median, 34.3 to 19.7 mg/dL). Patients not treated with cyclosporin A (group II) exhibited mean LDL-C and median Lp(a) levels (118 +/- 42 and 33.1 mg/dL, respectively) that were remarkably similar to those observed before renal transplantation (group I). These data confirm that hyperlipidemia following renal transplantation is associated with cyclosporin A therapy and show that this drug has opposing effects on plasma Lp(a) and LDL-C accumulations.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
LDL-Colesterol/sangue , Ciclosporina/farmacologia , Transplante de Rim , Rim/fisiopatologia , Lipoproteína(a)/sangue , Diálise Renal , Adulto , HDL-Colesterol/sangue , Ciclosporina/efeitos adversos , Ciclosporina/uso terapêutico , Humanos , Falência Renal Crônica/fisiopatologia , Falência Renal Crônica/terapia , Pessoa de Meia-Idade , Nefrectomia , Prednisona/uso terapêutico
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