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3.
Eur Ann Allergy Clin Immunol ; 41(1): 17-22, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19496348

RESUMO

OBJECTIVES: To determine the prevalence of sensitization to lupin flour in patients consulting allergists, in order to evaluate the risk of primary and secondary allergies to lupin. METHODS: A prospective study carried out by members of the Allergy Vigilance Network, using prick-tests with a commercial lupin flour extract in patients with various allergic symptoms. The study design classified patients into four groups: peanut allergy, current atopic disease, latent atopy, no atopy. Data were collected and analysed by Network coordinators. RESULTS: Over a two-month period, 88 French and Belgian allergists tested 5,366 patients: 2,680 children and 2,686 adults aged over 16 years. Of the 2,680 children, 11.15% presented with peanut allergy. The frequency of cross-reactivity with lupin was 17.1% for patients with peanut allergy, 2.5% for children with current atopic disease and 1.7% for healthy children with latent atopy. In the 2,686 adults, peanut allergy was diagnosed in 1.86% of patients with cross-reactivity to lupin in 14.6%. Sensitization to lupin was detected in 3.7% of patients with current atopic disease and in 1.8% of those with latent atopy. CONCLUSION: The relative frequency of latent sensitisation to lupin in patients of all ages presenting with atopic disease is a new factor indicating the likelihood of an increase in primary food allergies to lupin flour. This justifies the recent decision requiring mandatory labelling of lupin, and shows the need to inform consumers who may be unaware that this ingredient is being used increasingly. Sensitization to lupin should be searched by prick-tests in any case of peanut allergy. Prick-test to lupin may be valuable whenever a food allergy is suspected when no current food allergens have been identified.


Assuntos
Dermatite Atópica/epidemiologia , Dermatite Atópica/imunologia , Hipersensibilidade Alimentar/epidemiologia , Hipersensibilidade Alimentar/imunologia , Imunoglobulina E/metabolismo , Adulto , Antígenos de Plantas/efeitos adversos , Antígenos de Plantas/imunologia , Bélgica , Criança , Reações Cruzadas , Dermatite Atópica/complicações , Dermatite Atópica/terapia , Dessensibilização Imunológica , Feminino , Hipersensibilidade Alimentar/complicações , Hipersensibilidade Alimentar/terapia , França , Humanos , Imunoglobulina E/imunologia , Serviços de Informação , Lupinus/efeitos adversos , Lupinus/imunologia , Masculino , Mimetismo Molecular/imunologia , Extratos Vegetais/administração & dosagem , Prevalência , Estudos Prospectivos , Testes Cutâneos
4.
Int Arch Allergy Immunol ; 149(2): 91-7, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19127064

RESUMO

BACKGROUND: In vitro testing for food allergy may yield clinically irrelevant results due to cross-reactive carbohydrate determinants (CCD) specific immunoglobulin E (sIgE) induced by pollen exposure. The performances of 2 in vitro methods were evaluated for peanut sIgE measurement in patients allergic to grass pollen with or without subsequent allergy to peanuts. The correlation between clinically irrelevant peanut sIgE and the presence of CCD sIgE was investigated. METHODS: In vitro measurement of peanut sIgE was performed using the Pharmacia ImmunoCap system Radio Immuno Assay (RIA) and the Immulite 2000 3gAllergy system. Discrepancies between in vitro results and peanut allergy diagnosis were evaluated by measurement of CCD sIgE using bromelain and ascorbic acid oxydase (AAO). RESULTS: The sensitivity was 100% with both systems for the diagnosis of allergy to peanut (58 patients), nevertheless the specificity obtained with Immulite (73%) was better than that obtained using ImmunoCap (46%) in patients who were not allergic to peanuts, but who had a grass pollen allergy (n = 41). In 22 out of 41 patients who presented clinically irrelevant peanut sIgE results using ImmunoCAP, CCD sIgE was detected in 72% of the cases by bromelain and in 86% by AAO. In 11 patients out of 41 who presented irrelevant peanut sIgE results using Immulite, CCD sIgE was detected in 81% of the cases by bromelain and in 100% by AAO. CONCLUSION: The Immulite 2000 system had better specificity than the ImmunoCap system for accurate diagnosis of peanut allergy in patients allergic to grass pollen. CCD sIgE was identified in most of the false-positive peanut sIgE results.


Assuntos
Arachis/imunologia , Imunoensaio/métodos , Imunoglobulina E/sangue , Hipersensibilidade a Amendoim/diagnóstico , Pólen/imunologia , Rinite Alérgica Sazonal/imunologia , Bromelaínas/análise , Reações Cruzadas/imunologia , Humanos , Hipersensibilidade a Amendoim/imunologia , Sensibilidade e Especificidade
5.
Arch Ital Biol ; 146(1): 1-20, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18666444

RESUMO

During early periods of life, modifications of the gravitational environment affect the development of sensory, neuronal and motor systems. The vestibular system exerts significant effects on motor networks that control eye and body posture as well as swimming. The objective of the present study was to study whether altered gravity (AG) affects vestibuloocular and spinal motor systems in a correlated manner. During the French Soyuz taxi flight Andromède to the International Space Station ISS (launch: October 21, 2001; landing: October 31, 2001) Xenopus laevis embryos were exposed for 10 days to microgravity (microg). In addition, a similar experiment with 3g-hypergravity (3g) was performed in the laboratory. At onset of AG, embryos had reached developmental stages 24 to 27. After exposure to AG, each tadpole was tested for its roll-induced vestibuloocular reflex (rVOR) and 3 hours later it was tested for the neuronal activity recorded from the ventral roots (VR) during fictive swimming. During the post-AG recording periods tadpoles had reached developmental stages 45 to 47. It was observed that microgravity affected VR activity during fictive swimming and rVOR. In particular, VR activity changes included a significant decrease of the rostrocaudal delay and a significant increase of episode duration. The rVOR-amplitude was transiently depressed. Hypergravity was less effective on the locomotor pattern; occurring effects on fictive swimming were the opposite of microg effects. As after microgravity, the rVOR was depressed after 3g-exposure. All modifications of the rVOR and VR-activity recovered to normal levels within 4 to 7 days after termination of AG. Significant correlations between the rVOR amplitude and VR activity of respective tadpoles during the recording period have been observed in both tadpoles with or without AG experience. The data are consistent with the assumptions that during this period of life which is characterized by a progressive development of vestibuloocular and vestibulospinal projections (i) microgravity retards the development of VR activity while hypergravity weakly accelerates it; (ii) that microgravity retards the rVOR development while hypergravity caused a sensitization, and that (iii) AG-induced changes of VR activity during fictive swimming have a vestibular origin.


Assuntos
Hipergravidade , Reflexo Vestíbulo-Ocular/fisiologia , Raízes Nervosas Espinhais/fisiologia , Natação/fisiologia , Ausência de Peso , Xenopus laevis/crescimento & desenvolvimento , Potenciais de Ação/fisiologia , Envelhecimento/fisiologia , Animais , Tronco Encefálico/crescimento & desenvolvimento , Vias Eferentes/crescimento & desenvolvimento , Feminino , Sensação Gravitacional/fisiologia , Hipergravidade/efeitos adversos , Larva/anatomia & histologia , Larva/crescimento & desenvolvimento , Neurônios Motores/fisiologia , Músculos Oculomotores/inervação , Equilíbrio Postural/fisiologia , Recuperação de Função Fisiológica/fisiologia , Voo Espacial , Medula Espinal/crescimento & desenvolvimento , Núcleos Vestibulares/crescimento & desenvolvimento , Vestíbulo do Labirinto/fisiologia , Ausência de Peso/efeitos adversos , Xenopus laevis/anatomia & histologia
6.
Eur Ann Allergy Clin Immunol ; 39(6): 189-92, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17713170

RESUMO

Body piercing and tattooing are increasingly common. As well as the risk of infection and scarring, allergic reactions are also reported. This is the first multi-centre study to assess the frequency of consultations for allergy. Of the 138 allergologists who answered our two questionnaires, 7.9% reported allergic reactions associated with body piercing and 18.9% identified allergies associated with temporary henna-based tattoos. Contact eczema, rhinitis and urticaria were related to nickel allergy. Contact eczema, generalized eczema, pruritus and edema were caused by tattoos. In 20 out of 28 cases, sensitization to para-phenylenediamine (PPD) was observed. The authors review the literature, underscoring the risk of serious allergy to PPD, the need for long-term monitoring of the risk of skin lymphocytoma, the difficulties met during treatment and the necessity of regulating tattooing and body piercing practices.


Assuntos
Piercing Corporal/efeitos adversos , Hipersensibilidade/epidemiologia , Hipersensibilidade/etiologia , Tatuagem/efeitos adversos , Humanos , Estudos Retrospectivos
7.
Protoplasma ; 229(2-4): 193-203, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17180501

RESUMO

In lower vertebrates, gravity deprivation by orbital flights modifies the vestibuloocular reflex. Using the amphibian Xenopus laevis, the experiments should clarify to which extent macular structures of the labyrinth are responsible for these modifications. In particular, the shape of otoconia and number and size of sensory macular cells expressing CalBindin were considered. CalBindin is common in mature sensory cells including vestibular hair cells and is probably involved in otoconia formation. Two developmental stages were used for this study: stage 26/27 embryos, which were unable to perform the roll-induced vestibuloocular reflex (rVOR) at onset of microgravity, and stage 45 tadpoles, which had already developed the reflex. The main observations were that the developmental progress of the animals was not affected by microgravity; that in the young tadpole group with normal body shape the rVOR was not modified by microgravity, while in the older group with microgravity experience, the rVOR was augmented; and that significant effects on the shape of otoconia and on the number and size of CalBindin-expressing cells of the labyrinthine maculae cells were absent. In addition, behavioural data were never significantly correlated with morphological features of macular structures such as size and number of CalBindin-expressing cells. It is postulated that mechanisms of vestibular adaptation to microgravity during early development are probably based on mechanisms located in central structures of the vestibular system.


Assuntos
Sensação Gravitacional , Reflexo Vestíbulo-Ocular , Voo Espacial , Vestíbulo do Labirinto/anatomia & histologia , Ausência de Peso , Xenopus laevis/anatomia & histologia , Adaptação Fisiológica , Animais , Calbindinas , Células Ciliadas Vestibulares/química , Larva/anatomia & histologia , Larva/fisiologia , Membrana dos Otólitos/fisiologia , Membrana dos Otólitos/ultraestrutura , Proteína G de Ligação ao Cálcio S100/análise , Vestíbulo do Labirinto/química , Vestíbulo do Labirinto/fisiologia , Xenopus laevis/fisiologia
10.
Presse Med ; 32(2): 61-6, 2003 Jan 18.
Artigo em Francês | MEDLINE | ID: mdl-12653027

RESUMO

INTRODUCTION: The management in schools of children with life-threatening or chronic diseases has led to the development of Individual Reception Projects (IRP) since 1993, notified in the state education ministry's circular letter. The aim of this study was to assess the status of such IRPs in France and the French Overseas Territories in the management of food allergy risks. METHOD: The regional departments of educational promotion were contacted and the survey was run between May and June, 2002. The items of the questionnaire were: the number of IRPs for anaphylactic emergencies, details on the allergies themselves, an overview of the eventual existence of dialogue structures among school physicians, heads of schools, allergists, treatment prescribers and emergency protocols. RESULTS: The total survey revealed 7482 IRP for anaphylactic reactions to food (14% of the total IRPs). The frequency of IRPs varied greatly depending on the regions. The Paris area represented 36.3% of the total. The Lorraine area: 5.6%, the Haute-Garonne: 5%, and the Bouches-du-Rhône: 3.3%. The IRPs represented 0.002 (Ardèche) to 0.33% (Alpes-de-Haute-Provence) of the school attending population. The mean level was of 0.065%; 71.6% of the IRPs concerned the 1st grade (1 IRP for 1091 children). In decreasing frequency, the allergens concerned were: peanuts, eggs, dried nuts, fish, dried peas and milk. Dialogue structures were established in 38 regions. DISCUSSION: The IRPs have increased 4-fold since the circular letter in 1999. The enhanced prevalence of numerous (new) allergies to dried nuts and leguminous plants has been emphasized, and peanut allergies have been confirmed. The complexity of managing the IRPs and need for information and training of state education and municipal staff requires the further development of dialogue structures, which are still clearly insufficient.


Assuntos
Anafilaxia , Serviços Médicos de Emergência , Hipersensibilidade Alimentar , Adolescente , Fatores Etários , Alérgenos , Criança , França , Humanos , Paris , Fatores de Risco , Inquéritos e Questionários
11.
Int Arch Allergy Immunol ; 128(3): 212-9, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12119503

RESUMO

BACKGROUND: Numerous products based on soybean are available and various food technologies are applied for their production. The allergenicity of natural soybean may be modified by these treatments. OBJECTIVES: To compare the allergenicity of native soybean proteins with those of soy milk and texturized protein products. To show additional allergens. METHODS: Three commercial products and two infant formulas were studied: Soybean flour, soy milk, texturized soy proteins, two infant formulas; the first containing total proteins and the second containing a soy protein hydrolysate. Sera from 9 patients allergic to soy protein were tested by immunoblotting (IB). IB inhibition was achieved by incubating sera with protein extract from soybean flour. RESULTS: The SDS-PAGE profile of soybean flour protein and soy milk showed a difference in the proportions of the various protein fractions, with a higher concentration of 37-kD protein in flour and 33-kD protein in milk. Infant formula 1 contained proteins with a molecular weight below 28 kD. The texturized extract contained high proportions of 31- to 34- and 38-kD proteins. Immunoblotting revealed a lack of allergenicity in infant formula. Sera recognizing the 38- and 50-kD proteins in texturized soy protein also recognized the 37- and 49-kD proteins in soybean flour and in soy milk, suggesting a protein glycation by texturization processes. The 30- to 34-kD band in texturized proteins was devoid of any allergenicity. This study seems to indicate that the 30-kD allergen (Gly m Bd 30) disappears during the production of texturized soy protein. CONCLUSION: All technologies applied to soybean-based products induce striking variation in the protein profile and allergenicity. Texturized protein could lack the major allergen Gly m Bd 30. Further studies or texturization might generate modified technologies in order to create hypoallergenic texturized proteins.


Assuntos
Alérgenos/imunologia , Manipulação de Alimentos/métodos , Hipersensibilidade Alimentar/imunologia , Tecnologia de Alimentos , Glycine max/imunologia , Adolescente , Alérgenos/química , Criança , Pré-Escolar , Proteínas Alimentares/análise , Proteínas Alimentares/imunologia , Eletroforese em Gel de Poliacrilamida , Feminino , Humanos , Immunoblotting , Imunoglobulina E/sangue , Masculino , Pessoa de Meia-Idade , Teste de Radioalergoadsorção , Testes Cutâneos , Proteínas de Soja/análise , Proteínas de Soja/imunologia , Glycine max/química
12.
Allerg Immunol (Paris) ; 34(6): 194-8, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12134641

RESUMO

The Allergo-vigilance Network including 200 French allergologists and 28 European ones, has three objectives: to index the cases of lethal or prelethal anaphylaxis, to evaluate the prevalence of food allergies, clinical pictures and allergens, and to implement the post-marketing surveillance of the allergic risk of novel foods. The first survey dealing with life-threatening food allergies leads to an estimation of 15,000 to 30,000 reactions per year in France. The AVN could be a helpful tool for public health organizations.


Assuntos
Anafilaxia/epidemiologia , Bases de Dados Factuais , Hipersensibilidade Alimentar/epidemiologia , Inquéritos Epidemiológicos , Edema Laríngeo/epidemiologia , Vigilância da População , Adulto , África do Norte/epidemiologia , Anafilaxia/etiologia , Arachis/efeitos adversos , Argentina/epidemiologia , Asma/epidemiologia , Asma/etiologia , Criança , Reações Cruzadas , Proteínas Alimentares/efeitos adversos , Europa (Continente)/epidemiologia , França/epidemiologia , Frutas/efeitos adversos , Humanos , Edema Laríngeo/etiologia , Hipersensibilidade ao Látex/epidemiologia , Martinica/epidemiologia , Nozes/efeitos adversos , Prevalência , Reunião/epidemiologia , Estados Unidos/epidemiologia
14.
Allergy ; 56(11): 1071-6, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11703221

RESUMO

BACKGROUND: Children with severe food allergies can benefit from a personalized care project (PCP) in schools. The usefulness of the PCP and the residual risk of allergic emergencies are poorly appreciated. The objective was to evaluate the efficiency of the management plan and the training in the use of the emergency kit. METHODS: A telephone survey using a detailed questionnaire was performed in 45 families whose children had been previously referred to the department. The distribution of disorders was as follows: asthma, 37.7%; atopic dermatitis and asthma, 28.8%; atopic dermatitis, 15.5%; angioedema and urticaria, 13.3%; and anaphylactic shock, 4.2%. Food allergy had been diagnosed in the 45 children by past history, and double-blind or single-blind, placebo-controlled food challenges (DBPCFCs, or SBPCFCs) with evidence of specific IgE. Exactly 75.5% of the children had peanut allergy. Multiple food allergies characterized 46.8% of the subjects. They had benefited from a strict elimination diet and a protocol for emergency care including a ready-to-use intramuscular epinephrine injection. A PCP had been requested by the School Public Health Service. RESULTS: Thirty-nine PCPs were implemented (86.5% of the requests). They represented 63% of the PCPs for food allergy in the eastern region of France: one per 5800 school-age children. The retrospective period of evaluation was 25 months on average. The types of meals were very diverse, and medically acceptable in 83% of cases. The place where the emergency kit was stored in the school varied. Forty reactions occurred in 33% of the children (5/6 times in the absence of a PCP), asthma in 28%, shock in 1%, and immediate skin reactions in 11%. Reactions occurred at home in 78% of the subjects, and in school in 22% of the subjects. The cause of the reactions was not specifically known in 63% of cases. Twenty-seven percent of the reactions were linked to the ingestion of food allergens. In 10% of subjects, the reaction was due to a modification of ingredients by the food industry. CONCLUSIONS: The frequency of respiratory symptoms during oral challenge tests was confirmed by the frequency of asthmatic reactions within the follow-up period. The role of hidden allergens and of misleading labeling validates the need for PCPs in the case of peanut and tree nut allergies, past history of severe reactions, multiple food allergies, reactions to a low dose in DBPCFCs, and asthmatic reactions to foods. This study provides encouraging data on the usefulness of PCPs and confirms the need for thorough instruction and training of the school staff in dealing with allergic emergencies. Addition of a beta-agonist spray to the emergency kit is suggested.


Assuntos
Anafilaxia/etiologia , Hipersensibilidade Alimentar/complicações , Serviços de Saúde Escolar , Adolescente , Agonistas Adrenérgicos beta/uso terapêutico , Adulto , Anafilaxia/terapia , Angioedema/etiologia , Especificidade de Anticorpos/imunologia , Arachis/efeitos adversos , Asma/etiologia , Criança , Proteção da Criança , Pré-Escolar , Dermatite Atópica/etiologia , Método Duplo-Cego , Ovos/efeitos adversos , Epinefrina/uso terapêutico , Feminino , Seguimentos , Hipersensibilidade Alimentar/imunologia , Hipersensibilidade Alimentar/terapia , França/epidemiologia , Humanos , Imunoglobulina E/imunologia , Masculino , Valor Preditivo dos Testes , Teste de Radioalergoadsorção , Método Simples-Cego , Testes Cutâneos , Inquéritos e Questionários , Resultado do Tratamento
15.
Adv Space Res ; 27(2): 433-45, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11642305

RESUMO

The study of the influence of weightlessness on fertilization and embryonic development of a vertebrate is of importance in the understanding of basic embryogenesis and in the preparation of the future exploration of space. Accordingly, specific hardware was designed to perform experiments on board the MIR space station with an amphibian vertebrate model, taking into account the biological requirements and the multiple constraints of a long-term mission. This paper describes the biological uses and presents the technological specifications of the device developed under CNES management. The hardware was adapted to and is compatible with biological requirements as confirmed by three experiments performed in space on board the orbital MIR station.


Assuntos
Abrigo para Animais , Modelos Animais , Pleurodeles/embriologia , Voo Espacial/instrumentação , Ausência de Peso , Animais , Desenvolvimento Embrionário , Desenho de Equipamento , Estudos de Viabilidade , Feminino , Fertilização/fisiologia , Masculino , Pleurodeles/crescimento & desenvolvimento , Astronave/instrumentação
17.
Dev Growth Differ ; 43(3): 315-26, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11422297

RESUMO

The FERTILE experiment was twice performed onboard the Mir space station during the Cassiopée and Pégase French space missions. The goal was to analyze the effects of microgravity on fertilization and embryonic development, and then on further development on the ground in the amphibian Pleurodeles waltl. The present paper reports development that occurred in the laboratory after landing. Recovered on the ground at the hatching stage, young larvae reared at room temperature underwent metamorphosis and became adults without obvious abnormalities. Of particular interest was the rearing temperature that induced a delayed metamorphosis for animals from the Cassiopée space mission, but not for animals from the Pégase mission. The rate of development and the morphology were analogous in these animals and in ground controls reared in a similar annual period. Analysis of offspring was performed using these animals. Males born in space were first mated with control ground-born females and then with females born in space. The mating gave progeny that developed normally. Depending on the methods used and on the limits of the analyses, the results clearly demonstrated that animals born in space were able to live and reproduce after return to the ground.


Assuntos
Pleurodeles/fisiologia , Voo Espacial , Ausência de Peso , Animais , Embrião não Mamífero/fisiologia , Desenvolvimento Embrionário , Feminino , Larva/crescimento & desenvolvimento , Larva/fisiologia , Masculino , Metamorfose Biológica , Peptídeo Hidrolases/metabolismo , Pleurodeles/embriologia , Pleurodeles/crescimento & desenvolvimento , Temperatura
18.
Adv Space Res ; 28(4): 569-78, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11799990

RESUMO

Pleurodeles waltl (amphibian, Urodele) is an appropriate biological model for space experiments on a vertebrate. One reason for interest in this animal concerns the study of the effects of absence of gravity on embryonic development. First, after mating (on Earth) the females retain live, functional sperm in their cloacum for up to 5 months, allowing normal in vivo fertilisation after hormonal stimulation. Second, their development is slow, which allows analyses of all the key stages of ontogenesis from the oocyte to swimming tailbud embryos or larvae. We have performed detailed studies and analyses of the effects of weightlessness on amphibian Pleurodeles embryos, fertilised and allowed to develop until the swimming larvae stage. These experiments were performed in space during three missions on the MIR-station: FERTILE I, FERTILE II and NEUROGENESIS respectively in 1996, 1998 and 1999. We show that in microgravity abnormalities appeared at specific stages of development compared to 1g-centrifuge control embryos and 1g-ground control embryos. In this report we describe abnormalities occurring in the central nervous system. These modifications occur during the neurulation process (delay in the closure of the neural tube and failure of closure of this tube in the cephalic area) and at the early tailbud stage (microcephaly observed in 40% of the microgravity-embryos). However, if acephalic and microcephalic embryos are not taken into account, these abnormalities did not disturb further morphological, biochemical and functional development and the embryos were able to regulate and a majority of normal hatching and swimming larvae were obtained in weightlessness with a developmental time-course equivalent to that of 1g-centrifuge control embryos (on the MIR station) and 1g-ground control embryos.


Assuntos
Sistema Nervoso Central/embriologia , Modelos Animais , Pleurodeles/fisiologia , Voo Espacial , Ausência de Peso , Animais , Astrócitos/fisiologia , Sistema Nervoso Central/anormalidades , Sistema Nervoso Central/crescimento & desenvolvimento , Sistema Nervoso Central/fisiologia , Colina O-Acetiltransferase/metabolismo , Proteínas do Citoesqueleto/metabolismo , Orelha/embriologia , Embrião não Mamífero/anormalidades , Embrião não Mamífero/embriologia , Embrião não Mamífero/fisiologia , Desenvolvimento Embrionário , Olho/embriologia , Feminino , Larva/crescimento & desenvolvimento , Larva/fisiologia , Masculino , Atividade Motora , Pleurodeles/anormalidades , Pleurodeles/embriologia , Pleurodeles/crescimento & desenvolvimento , Ácido gama-Aminobutírico/metabolismo
19.
Biol Reprod ; 63(2): 551-8, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10906064

RESUMO

Effects of microgravity (microG) on fertilization were studied in the urodele amphibian Pleurodeles waltl on board the MIR space station. Genetic and cytomorphologic analyses ruled out parthenogenesis or gynogenesis and proved that fertilization did occur in microG. Actual fertilization was demonstrated by the analysis of the distribution of peptidase-1 genes, a polymorphic sex-linked enzyme, in progenies obtained in microG. Further evidence of fertilization was provided by the presence of spermatozoa in the perivitelline space and in the fertilization layer of the microG eggs and by the presence of a female pronucleus and male pronuclei in the egg cytoplasm. Experiments in microG and in 1.4G, 2G, and 3G hypergravity showed for the first time that, compared to eggs in 1G, several characteristics of the fertilization process including the cortical reaction and the microvillus transformations were altered depending on the gravitational force applied to the eggs. Microvillus elevation, the most evident feature, was reduced on microG-eggs and amplified on eggs submitted to 2G and 3G. No lethal consequences of these alterations on the early development of microG-eggs were observed.


Assuntos
Fertilização , Hipergravidade , Voo Espacial , Urodelos/embriologia , Ausência de Peso , Animais , Fase de Clivagem do Zigoto , Embrião não Mamífero/ultraestrutura , Desenvolvimento Embrionário , Feminino , Genótipo , Hormônio Liberador de Gonadotropina/farmacologia , Larva/genética , Masculino , Microvilosidades/ultraestrutura , Óvulo/ultraestrutura , Processos de Determinação Sexual , Urodelos/fisiologia
20.
Brain Res Brain Res Rev ; 28(1-2): 19-24, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9795111

RESUMO

As a result of previous studies using hypergravity (centrifuge) or virtual microgravity (clinostat), it was proposed that gravity was involved in embryonic development, i.e., in the establishment of the embryonic polarities and the body plan pattern which subsequently direct morphogenesis and organogenesis of the central nervous system and of sensory organs. Recent experiments were performed in space using sounding rockets and orbiting space-modules to ascertain whether gravity is indeed required for embryogenesis in Invertebrates and Vertebrates. Eggs fertilised in vivo or in vitro in microgravity showed some abnormalities during embryonic development but were able to regulate and produce nearly normal larvae.


Assuntos
Anfíbios/embriologia , Gravitação , Sistema Nervoso/embriologia , Animais , Embrião não Mamífero/fisiologia
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