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1.
Prensa méd. argent ; 95(10): 659-666, dic. 2008. ilus, graf
Artigo em Espanhol | LILACS | ID: lil-534094

RESUMO

This study analyzes the temporal-spatial correlation between angio-and corticogenesis in the developing chick optic tectum (OT) by means of NADPH-diaphorase and immunolabeling methods. Qualitative and quantitative parameters were used to analyze a new vessels formation and growth of preexisting ones as a function of time and space...


Assuntos
Embrião de Galinha , Movimento Celular/fisiologia , Neovascularização Patológica/patologia , Proliferação de Células , Sistema Nervoso Central/embriologia , Veias Cerebrais/patologia , Vias Visuais/anatomia & histologia , Anisotropia
2.
Conf Proc IEEE Eng Med Biol Soc ; 2004: 857-60, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-17271812

RESUMO

This paper analyzes the dynamics of cell proliferation in the developing central nervous system. Three different algorithms, Fano factor, Allan factor and detrended fluctuations analysis, are used to estimate de scaling exponent of space numerical series obtained by recording the number and position of proliferating cells along the cephalic-caudal axis of the system. It can be concluded that the dynamics of proliferation involves two component: (a) a random noncorrelated stochastic component representing a basal proliferating activity uniformly distributed along the cephalic-caudal axis and (b) a deterministic nonstationary component that imposes a defined global trend to the process. The deterministic nonstationary trend can be interpreted as the effect of a controlling influence operating along the cephalic-caudal axis. This result indicates that the proliferative activity is spatially organized along the cephalic-caudal axis of the system.

3.
Neurochem Res ; 23(9): 1185-90, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9712189

RESUMO

Plasminogen activators play key roles in several developmental events. In previous works we demonstrated the existence of typical developmental patterns of protease activity in the chick optic lobe and cerebellum. The aim of this work is to study the temporal pattern of development of plasminogen activator activity in the brain hemispheres. Plasminogen activator activity was assayed in soluble fractions derived by ultracentrifugation from Triton X-100 treated membrane fractions by using a radial fibrinolytic assay. Employing different inhibitors and anti-plasminogen activators antibodies we showed that developing brain hemispheres express only one type of enzyme which corresponds to the urokinase-type. Other results indicate that the protease activity displays a temporal pattern which completely differs from those of general parameters of development. This suggests that the plasminogen activator activity is developmentally regulated and could display specific functions during particular stages of development.


Assuntos
Cerebelo/enzimologia , Regulação da Expressão Gênica no Desenvolvimento , Teto do Mesencéfalo/embriologia , Ativador de Plasminogênio Tecidual/genética , Ativador de Plasminogênio Tipo Uroquinase/genética , Envelhecimento , Animais , Cerebelo/embriologia , Cerebelo/crescimento & desenvolvimento , Embrião de Galinha , Galinhas , Indução Embrionária , Regulação Enzimológica da Expressão Gênica , Teto do Mesencéfalo/enzimologia , Teto do Mesencéfalo/crescimento & desenvolvimento , Ativador de Plasminogênio Tecidual/metabolismo , Ativador de Plasminogênio Tipo Uroquinase/metabolismo
4.
Int J Dev Neurosci ; 15(6): 805-12, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9402231

RESUMO

Plasminogen activators are serine proteases which play a key role in morphogenesis and tissue remodelling. Two different molecular types, tissue-type and urokinase-type, were identified and they were postulated to play a role in neural development. The developing chick optic lobe plays a central role in processing visual information. In previous studies we demonstrated the occurrence of high levels of plasminogen activator activity in this model. The aim of the present paper is to study the temporal pattern of expression of this activity and characterize the type of plasminogen activator expressed in the developing optic lobe. Using soluble fractions derived by ultracentrifugation from Triton X-100-treated membrane fractions we measured the protease activity with a radial fibrinolytic assay. Employing different inhibitors of fibrinolytic activity and a zymographic assay, we showed that the developing optic lobe expresses only one type of plasminogen activator which corresponds to an urokinase-type of 70 kDa. Our results indicate that peaks of protease activity temporally correlate with massive neuronal migration, neurite outgrowth and synapse formation and maturation. This suggests that a plasminogen activator could play a role in these developmental events. This consistent pattern of variability strongly suggests that it is developmentally regulated and, if so, it could be a reliable parameter to study neural plastic changes induced by modifications in the environmental stimulation.


Assuntos
Lobo Óptico de Animais não Mamíferos/metabolismo , Ativadores de Plasminogênio/metabolismo , Animais , Embrião de Galinha , Endopeptidases , Modelos Lineares , Morfogênese , Lobo Óptico de Animais não Mamíferos/embriologia
5.
Int J Dev Neurosci ; 15(7): 875-82, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9568535

RESUMO

Plasminogen activators are considered to be involved in several developmental events. The present work aims at characterizing the developmental pattern of expression of plasminogen activators in the chick cerebellum. Soluble fractions derived by ultracentrifugation from Triton X-100 treated membrane fractions were used for determination of the enzyme activity with a radial fibrinolytic assay. By using specific inhibitors and different anti-plasminogen activators antibodies it is shown that only one type of the enzyme, the urokinase-type plasminogen activator, is expressed during the cerebellum ontogeny. Our results show the existence of a bimodal pattern of enzyme activity with two peaks that temporally coincide with the processes of massive neuronal migration, neurite outgrowth and synapse formation and plasticity. It is proposed that plasminogen activator could play a role in these developmental events and that its pattern of variability is developmentally regulated.


Assuntos
Cerebelo/metabolismo , Ativadores de Plasminogênio/metabolismo , Animais , Cerebelo/embriologia , Embrião de Galinha , Lobo Óptico de Animais não Mamíferos/embriologia , Lobo Óptico de Animais não Mamíferos/metabolismo , Inativadores de Plasminogênio/metabolismo , Fatores de Tempo
6.
Int J Dev Neurosci ; 13(8): 835-43, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8770657

RESUMO

This paper describes the development of the serotonergic innervation of the chick tectum opticum as revealed by an immunohistochemical methodology. The development of this innervation was previously described simply as the formation of an irregular network of serotonergic fibers that gradually invades the organ and increases in density. Our results show that the developmental pattern of serotonergic innervation differs significantly through the distinct tectal layers and that it progresses through a characteristic temporospatial pattern related to the lamination process. These findings support the idea that the concept of laminar segregation can be applied to describe the development of the serotonergic innervation. On the other hand, it is clear that the existence of a typical ordered developmental pattern of innervation makes it possible to detect embryonic or post-hatching alterations. Thus, the tectal serotonergic innervation could be used as a suitable model to investigate possible plastic changes in experimental conditions.


Assuntos
Serotonina/fisiologia , Colículos Superiores/embriologia , Animais , Diferenciação Celular/fisiologia , Divisão Celular/fisiologia , Embrião de Galinha , Imuno-Histoquímica , Neuroglia/fisiologia , Plasticidade Neuronal/fisiologia , Neurônios/fisiologia , Colículos Superiores/citologia , Sinapses/fisiologia
7.
Int J Dev Neurosci ; 13(8): 845-58, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8770658

RESUMO

Several ontogenetic studies have been devoted to the structural organization of the developing tectum opticum. They disagree in many respects because they are based on histological preparations performed with differently oriented planes of section. According to our results the differences found in the literature mainly result from the fact that the developmental gradient axis undergoes remarkable positional changes with respect to both optic lobe and neural tube longitudinal anatomical axes during the early stages of development. The present work is a dynamic description of the tectum opticum lamination based on sections coinciding with the developmental gradient. Since this latter displays a curved disposition, several slightly modified planes of section had to be used to obtain a complete picture along the developmental gradient. The development of the tectal architecture proceeds from a relatively simple organization through increasingly complex multilaminated patterns. A dynamic interpretation of successive images of a particular region observed at increasing developmental stages or of images observed at a particular stage along the entire length of the developmental gradient axis, allows us to propose that embryonic laminae are only transient spatial arrangements of cells actively migrating from the sites where they were generated to those where they will definitively reside. These considerations led us to define a nomenclature that establishes clear correlations between the early transient organizations and the definitive one of the fully developed optic tectum. This type of nomenclature could be usefully applied to describe dynamically the development of structures displaying multilaminated patterns such as other cortical zones of the central nervous system.


Assuntos
Galinhas/fisiologia , Colículos Superiores/anatomia & histologia , Colículos Superiores/embriologia , Animais , Embrião de Galinha , Terminologia como Assunto
8.
Neurochem Res ; 20(2): 137-42, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7783837

RESUMO

Determinations of plasminogen activator (PA) activity are usually performed in Triton X-100-treated tissue homogenates or crude membrane fractions. Such preparations usually involve a single Triton X-100 treatment. In the present paper we describe the pattern of variability of PA activity measured in different fractions obtained from the developing chick CNS by a repetitive procedure of Triton X-100 treatment and ultracentrifugation. To further characterize this PA activity we have also performed zymographic analyses during the embryonic development and the early postnatal life. Our results show that: a) a single Triton X-100 treatment does not completely extract the enzyme and this lead to an underestimation of the total PA activity; b) the PA activity is associated with the particulate component of the total tissue homogenate requiring its complete solubilization more drastic Triton X-100 treatments; c) better estimations of total and specific activities are obtained by using soluble fractions derived by ultracentrifugation from Triton X-100-treated membrane fractions; d) the developing chick optic lobe expresses only one kind of PA molecule along the entire development; e) the level of PA activity vary characteristically during the ontogeny and the early postnatal life indicating the existence of a developmentally regulated mechanism of PA expression.


Assuntos
Octoxinol , Ativadores de Plasminogênio/isolamento & purificação , Teto do Mesencéfalo/enzimologia , Envelhecimento/fisiologia , Animais , Embrião de Galinha , Galinhas , Desenvolvimento Embrionário e Fetal , Fibrinólise , Regulação Enzimológica da Expressão Gênica , Ativadores de Plasminogênio/biossíntese , Ativadores de Plasminogênio/metabolismo , Teto do Mesencéfalo/embriologia , Teto do Mesencéfalo/crescimento & desenvolvimento , Ultracentrifugação/métodos
9.
Int J Dev Neurosci ; 10(4): 331-40, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1414445

RESUMO

Several ontogenetic studies performed in different species suggest a developmental role for 5-HT neurons. The 5-HT system interconnecting the CNS and the tentacular sensory organs in pulmonates is a suitable model for studying the postulated developmental role of 5-HT neurons. In this paper we describe the behavior of the 5-HT fibers during the early stages of blastema reinnervation, primordium formation and differentiation of regenerating tentacular sensory organs in the pulmonate snail Cryptomphalus aspersa. Our results show that the regeneration process allows the development of a normal pattern of 5-HT innervation of the regenerated sensory organs and suggest that 5-HT could be involved in reciprocal developmental interactions with regenerating tentacular tissues.


Assuntos
Regeneração Nervosa/fisiologia , Órgãos dos Sentidos/fisiologia , Serotonina/fisiologia , Caramujos/fisiologia , Animais , Imuno-Histoquímica , Fibras Nervosas/fisiologia , Fenômenos Fisiológicos Oculares , Regeneração , Cicatrização/fisiologia
10.
Chir Ital ; 40(3): 230-6, 1988 Jun.
Artigo em Italiano | MEDLINE | ID: mdl-3228927

RESUMO

From february 1980 to december 1985, 115 breast carcinomas were treated with QU.A.RT. with limited surgery and following radiotherapy. Median age was 51 years (range 25 to 75). Surgical approach was quadrantectomy with axillary nodes dissection. Irradiation of residual breast was performed by an anterior high energy electron beam. 50 Gy in 25 fractions was the minimal dose to whole breast. In pN+ patients systemic adjuvant therapy was done. Local control was obtained in 111 cases. Local recurrence appeared in 4: 1 menopausal pT1 pNO and 3 premenopausal (1 pT1 pNO and 2 pT1 pN+) at respectively 31, 19, 22 months from diagnosis. Distant metastases appeared in 10 patients. 7 died for cancer and 3 are still alive. Cosmetic results were scored as good in 52, better than mastectomy in 26, unsatisfactory in 3, and not stated in 34. Our results are comparable to those of other Centers. Youth, axillary metastases and delay between surgery and radiotherapy appears to influence the risk of recurrence also in our series.


Assuntos
Neoplasias da Mama/cirurgia , Carcinoma/cirurgia , Adulto , Fatores Etários , Idoso , Neoplasias da Mama/patologia , Neoplasias da Mama/radioterapia , Carcinoma/patologia , Carcinoma/radioterapia , Terapia Combinada , Feminino , Humanos , Mastectomia Segmentar , Menopausa , Pessoa de Meia-Idade , Estudos Retrospectivos
11.
Chir Ital ; 40(3): 225-9, 1988 Jun.
Artigo em Italiano | MEDLINE | ID: mdl-3067880

RESUMO

A case of splenic artery aneurysm with ultrasonic examination discovered is reported and analyzed. The aneurysm pas asymptomatic and founded as incidental finding during standard x-ray. Arteriography was required to confirm the diagnosis and indicate the correct surgical treatment.


Assuntos
Artéria Esplênica , Aneurisma/diagnóstico , Aneurisma/diagnóstico por imagem , Feminino , Humanos , Pessoa de Meia-Idade , Radiografia , Ultrassonografia
12.
Chir Ital ; 40(1): 37-47, 1988 Feb.
Artigo em Italiano | MEDLINE | ID: mdl-3282703

RESUMO

The authors illustrate the ultrasound features of gallbladder carcinoma after reviewing literature and basing upon their own experience. The diagnosis of this neoplasia is formulated more frequently today by introduction of scanning means, but it remains very difficult on initial phase because of its precocious lymphatic and hilar infiltration.


Assuntos
Neoplasias da Vesícula Biliar/diagnóstico , Ultrassonografia , Idoso , Idoso de 80 Anos ou mais , Colelitíase/diagnóstico , Diagnóstico Diferencial , Feminino , Neoplasias da Vesícula Biliar/diagnóstico por imagem , Humanos , Masculino , Tomografia Computadorizada por Raios X
13.
Chir Ital ; 39(5): 515-22, 1987 Oct.
Artigo em Italiano | MEDLINE | ID: mdl-3690785

RESUMO

The Authors report on a case of duodenal leiomyosarcoma of small dimensions in a paravaterian site and presenting a low degree of histological malignity. They summarize the main anatomoclinical features of the neoplasm and conclude by indicating less aggressive surgical therapy as adequate in such cases, accompanied, however, by a protracted post-operative follow-up.


Assuntos
Neoplasias Duodenais/patologia , Leiomiossarcoma/patologia , Neoplasias Duodenais/cirurgia , Feminino , Humanos , Leiomiossarcoma/cirurgia , Pessoa de Meia-Idade
14.
Chir Ital ; 39(5): 507-14, 1987 Oct.
Artigo em Italiano | MEDLINE | ID: mdl-3319244

RESUMO

On reviewing a consecutive series of 1,200 ultrasonic tomographies of the liver to assess the incidence of liver angiomas, the authors describe their sonographic, tomodensitometric and angiographic characteristics. They emphasise the fact that such lesions, though usually not constituting a serious clinical or diagnostic problem, as a simple sonographic follow-up will suffice to clarify the situation, may nevertheless, in certain particular clinical situations such as in the course of tumour staging of the digestive apparatus, require full diagnostic investigation using all the techniques available (ultrasonic tomography, CAT, liver arteriography, sonographically guided thin-needle biopsy.


Assuntos
Hemangioma/diagnóstico , Neoplasias Hepáticas/diagnóstico , Ultrassonografia , Adulto , Idoso , Neoplasias do Sistema Digestório/patologia , Feminino , Artéria Hepática/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Tomografia Computadorizada por Raios X
15.
Chir Ital ; 38(6): 592-600, 1986 Dec.
Artigo em Italiano | MEDLINE | ID: mdl-3568223

RESUMO

The authors review the epidemiological and aetiopathogenetic characteristics of abdominal blunt injuries (118 cases) monitored in a homogeneous manner. The relatively young age of the patients, the diagnostic difficulties encountered and the frequent presence of associated lesions call for the rigorous application of a predetermined clinico-diagnostic protocol.


Assuntos
Traumatismos Abdominais/epidemiologia , Ferimentos não Penetrantes/epidemiologia , Traumatismos Abdominais/etiologia , Fatores Etários , Feminino , Humanos , Itália , Masculino , Monitorização Fisiológica , Ferimentos não Penetrantes/etiologia
16.
Chir Ital ; 38(5): 543-8, 1986 Oct.
Artigo em Italiano | MEDLINE | ID: mdl-3815645

RESUMO

The authors report on a case of ductal adenoma of the breast, pointing out that routine clinico-instrumental diagnostic signs, though suggesting a picture of malignancy, may actually relate to this rare benign form of tumor. In the presence of cases of this type, we therefore advise a cautions approach to surgery, in that oncological radicality is subordinate to confirmation in the form of a traditional histological preparation, as freezer examinations are unable to provide wholly reliable responses.


Assuntos
Neoplasias da Mama/patologia , Mama/patologia , Papiloma/patologia , Adulto , Neoplasias da Mama/diagnóstico por imagem , Feminino , Humanos , Papiloma/diagnóstico por imagem , Radiografia
17.
Chir Ital ; 38(4): 412-20, 1986 Aug.
Artigo em Italiano | MEDLINE | ID: mdl-3545514

RESUMO

The authors report on a case of aggressive angiomyxoma of the pelvis and perineum in a 46-year-old female patient. After reviewing the cases described in the literature, they examine the clinical characteristics of this rare form of neoplasia, which tends to occur more frequently in patients of female sex and in the young to middle-aged age bracket and is characterized by slow growth, non-infiltration of adjacent organs and a tendency to recur owing to incomplete excision. Metastases have never been reported. Failure to recognize the tumor at first approach may be due to the fact that it is easy to confuse it clinically with other more common diseases of the perineum. The authors conclude by advising systematic anatomicopathological identification of all perineal tumors, even when apparently benign.


Assuntos
Mixoma/cirurgia , Neoplasias Pélvicas/cirurgia , Períneo , Feminino , Humanos , Pessoa de Meia-Idade , Mixoma/patologia , Recidiva Local de Neoplasia/diagnóstico , Neoplasias Pélvicas/patologia , Ultrassonografia
18.
Chir Ital ; 38(1): 72-9, 1986 Feb.
Artigo em Italiano | MEDLINE | ID: mdl-3518976

RESUMO

Splenic wandering is a rare condition of upset position of spleen, due to congenital fault or to excessive looseness of the supporting apparatus of this organ. The literature reports about 180 cases thereof, few of which recognized as such before operation. Ultimate investigations, in this limited number of preoperative diagnoses, resulted angiography and hepato-splenic scintigraphy; only three times the diagnosis was correctly placed through ultra-sounds. The authors show a case, confirmed by the operative report, where the ultrasonic test allowed to place the diagnosis with certainty, and, due to a particular lot of circumstances, proved to be better than TAC.


Assuntos
Baço/fisiopatologia , Ultrassonografia , Adulto , Humanos , Masculino , Movimento , Baço/diagnóstico por imagem , Baço/lesões , Baço/cirurgia , Tomografia Computadorizada por Raios X
19.
Chir Ital ; 37(6): 640-50, 1985 Dec.
Artigo em Italiano | MEDLINE | ID: mdl-3914380

RESUMO

Portal thrombosis is a rare acquired condition with various etiology. Clinical manifestations are portal hypertension or nine. The main technics to diagnostic are: CT, indirect splenoportography and ultrasound examination. The first and the second are reliable but the third only is useful to explore the portal system and to evaluate patients with suspect portal vein thrombosis.


Assuntos
Veia Porta , Trombose/diagnóstico , Tomografia Computadorizada por Raios X , Ultrassonografia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Veia Porta/diagnóstico por imagem , Trombose/diagnóstico por imagem
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