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1.
Eur Arch Paediatr Dent ; 23(4): 557-566, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35553398

RESUMO

PURPOSE: The study aimed to investigate associations between maternal vitamin D status during pregnancy and molar incisor hypomineralisation (MIH) and hypomineralised second primary molars (HSPM) among children. METHODS: The study had a longitudinal design using prospectively collected data from 176 mother and child pairs. Mothers were initially recruited in a randomised controlled trial to assess a pregnancy exercise programme. Along with the 7-year follow-up, we invited the children to a dental examination. The exposure variable was maternal serum 25-hydroxyvitamin D in gestational weeks 18-22 and 32-36, categorised as insufficient (< 50 nmol/l) and sufficient (≥ 50 nmol/l). Negative binomial hurdle models were used to analyse potential associations between the exposure variables and MIH or HSPM. The models were adjusted for potential confounders. RESULTS: Among the children (7-9 years old), 32% and 22% had at least one tooth with MIH or HSPM, respectively. A significant association was found between insufficient maternal vitamin D measured in gestational weeks 18-22 and the number of affected teeth among those with MIH at 7-9 years (adjusted RR = 1.82, 95% CI 1.13-2.93). CONCLUSION: Considering any limitations of the present study, it has been shown that insufficient maternal serum vitamin D at mid-pregnancy was associated with a higher number of affected teeth among the offspring with MIH at 7-9 years of age. Further prospective studies are needed to investigate whether this finding is replicable and to clarify the role of maternal vitamin D status during pregnancy and MIH, as well as HSPM, in children.


Assuntos
Hipoplasia do Esmalte Dentário , Criança , Hipoplasia do Esmalte Dentário/epidemiologia , Feminino , Humanos , Estudos Longitudinais , Dente Molar , Gravidez , Prevalência , Vitamina D
2.
BJOG ; 127(13): 1704-1711, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32479701

RESUMO

OBJECTIVE: To assess the association between levels of vitamin D and urinary incontinence (UI) in pregnancy. DESIGN: A cross-sectional study. Secondary analysis of a randomised controlled trial. SETTING: Two university hospitals in Norway. POPULATION: A total of 851 healthy, pregnant women >18 years in gestational weeks 18-22 with a singleton live fetus. METHODS: Data on UI were collected from a questionnaire at inclusion and serum analysis of 25-hydroxy vitamin D (25(OH)D) was performed. Univariable and multivariable logistic regression analyses were applied to study associations between exposure and outcomes. MAIN OUTCOME MEASURES: Prevalence of self-reported UI, stress (SUI) and urge (UUI) or mixed UI. RESULTS: In total, 230/851 (27%) of the participants were vitamin D insufficient (25(OH)D <50 nmol/l) and 42% reported to have any UI. Women with 25(OH)D <50 nmol/l were more likely to report any UI (P = 0.03) and SUI (P < 0.01) compared with women with 25(OH)D ≥50 nmol/l. In a univariable logistic regression analysis, serum levels of 25(OH)D <50 nmol/l was associated with increased risk of any UI (odds ratio [OR] 1.5 with 95% CI 1.0-2.1), SUI only (OR 1.7, 95% CI 1.2-2.4), but not mixed UI or UUI only (OR 0.8, 95% CI 0.5-1.5). In a multivariable logistic regression model, serum levels of 25(OH)D <50 nmol/l were associated with a higher risk of experiencing SUI only (OR 1.5, 95% CI 1.1-2.2). CONCLUSIONS: Serum 25(OH)D <50 nmol/l was associated with increased risk of any UI, and SUI in particular. TWEETABLE ABSTRACT: Low levels of vitamin D are associated with increased risk of urinary incontinence in pregnancy.


Assuntos
Complicações na Gravidez/sangue , Incontinência Urinária por Estresse/sangue , Vitamina D/análogos & derivados , Adulto , Estudos Transversais , Feminino , Humanos , Gravidez , Complicações na Gravidez/epidemiologia , Medição de Risco , Incontinência Urinária por Estresse/epidemiologia , Vitamina D/sangue
3.
BJOG ; 123(7): 1152-60, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26265465

RESUMO

OBJECTIVE: To investigate whether a customised exercise programme influences pregnant women's psychological wellbeing and general health perception reflecting health-related quality of life (HRQoL) in late pregnancy. DESIGN: A two-armed, two-centred randomised controlled trial. SETTING: Trondheim and Stavanger University Hospitals, Norway. POPULATION: A total of 855 healthy Caucasian pregnant women. METHODS: The intervention group was offered a 12-week exercise programme between 20 and 36 weeks of pregnancy. One weekly group session was led by physiotherapists, in addition women were encouraged to follow a home exercise programme at least twice a week. The exercise programme followed standard recommendations and included both aerobic and strength training. The control group received regular antenatal care. Pretests and post-tests were performed at 18-22 and 32-36 weeks of pregnancy. MAIN OUTCOME MEASURES: In the original study primary outcome was gestational diabetes mellitus, but in this report the primary outcome is HRQoL. The questionnaire Psychological General Wellbeing Index (PGWBI) was used to assess psychological wellbeing and self-perceived general health before and after the intervention. PGWBI contains six subscales and it is also possible to summarise all items to a global score. RESULTS: No association between antenatal exercise programme allocation and PGWBI (global score and subscales) was found. The study population was homogeneous and had high educational level. CONCLUSIONS: The results indicate that offering women an exercise programme during pregnancy does not seem to influence healthy pregnant women's psychological wellbeing and self-perceived general health. Further research is needed to investigate the effects of exercise in pregnancy on psychological wellbeing and self-perceived general health among women from different sociocultural subgroups. TWEETABLE ABSTRACT: Exercise in pregnancy does not influence healthy pregnant women's health-related quality of life.


Assuntos
Terapia por Exercício/psicologia , Qualidade de Vida , Adolescente , Adulto , Feminino , Promoção da Saúde/métodos , Nível de Saúde , Humanos , Gravidez , Terceiro Trimestre da Gravidez , Gestantes/psicologia , Cuidado Pré-Natal/métodos , Cuidado Pré-Natal/psicologia , Autoimagem , Resultado do Tratamento , Adulto Jovem
4.
ISRN Parasitol ; 2013: 123108, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-27335850

RESUMO

Spontaneous electrical activity is recorded in two species of marine cercariae, Cryptocotyle lingua and Himasthla elongata, with different types of swimming-by glass microelectrode recordings. Slow local field potentials (sLFPs) of low amplitude and fast high amplitude action potentials (APs) are found. The shape of the sLFPs is different in the species and correlates with the type of swimming. Fast high amplitude APs are recorded for the first time in cercariae. The limited number of APs included in the swimming pattern of larva suggests a key role for the spiking neurons in initiating the motility pattern in the cercaria and needs further research.

5.
Tissue Cell ; 38(4): 219-32, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16901523

RESUMO

Copulatory organs of eight species of the monophyletic taxon Childia were investigated in detail, using phalloidin fluorescence method and confocal microscopy. Childia species were shown to have one, two or several tubular stylets, conical to cylindrical in shape, composed of few to numerous needles. The musculature varied greatly, from the absence of seminal vesicle to extensively developed seminal vesicles with several additional types of specialized muscles. Ten copulatory organ characters were coded and mapped on the total evidence tree. The data obtained permitted to follow the evolution of the Childia stylet and to demonstrate that the structure of the stylet apparatus is largely consistent with the phylogeny of the group (CI=0.75). Possible function of different muscle specializations was discussed.


Assuntos
Evolução Biológica , Músculos/anatomia & histologia , Filogenia , Platelmintos/anatomia & histologia , Animais , Masculino , Microscopia Confocal , Microscopia de Fluorescência , Glândulas Seminais/anatomia & histologia
6.
Naturwissenschaften ; 93(6): 305-8, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16555097

RESUMO

The host-parasite relationship, Tenebrio molitor-Hymenolepis diminuta, was analyzed. The learning behavior of infected and uninfected (control) beetles in a T-maze was compared. The infected beetles moved much slower in the T-maze than the controls. The infected beetles reached the same level of learning as the controls. However, they needed more trials than the controls. The effect of the infection was already distinct after the first week and even higher after the second week. This indicates that the initial phase of infection caused stress in the beetles. Longer infection did not worsen their ability to learn. Thus, the parasites clearly changed the behavior of their intermediate host and probably made them more susceptible to their final host, the rat.


Assuntos
Comportamento Animal/fisiologia , Hymenolepis/isolamento & purificação , Tenebrio/parasitologia , Animais , Aprendizagem , Atividade Motora , Contagem de Ovos de Parasitas , Ratos
7.
Tissue Cell ; 38(2): 151-7, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16494908

RESUMO

The spatial relationship between the musculature and the NADPH-diaphorase (NADPH-d) activity, 5-HT and FMRFamide immunoreactivities in redia, cercaria and adult Echinoparyphium aconiatum was studied using scanning electron microscopy (SEM), NADPH-d histochemistry, immunocytochemistry, and confocal scanning laser microscopy (CSLM). TRITC-conjugated phalloidin was used to stain the musculature. Staining for NADPH-d was observed in the central (CNS) and peripheral nervous system (PNS) of all three stages. NADPH-d positive nerves occurred very close to muscle fibres. 5-HT-immunoreactive (5-HT-IR) nerve cells and fibres occurred in the CNS and PNS and close to muscle fibres. FMRFamide-IR nerve fibres were observed in the CNS and PNS of adult worms. This is the first time, the presence of the NADPH-d has been demonstrated in the larval as well as the adult stages of a fluke.


Assuntos
FMRFamida/imunologia , NADPH Desidrogenase/imunologia , Serotonina/metabolismo , Trematódeos/ultraestrutura , Animais , Sistema Nervoso Central/citologia , Sistema Nervoso Central/imunologia , Sistema Nervoso Central/ultraestrutura , FMRFamida/metabolismo , FMRFamida/farmacologia , Imuno-Histoquímica , Larva/ultraestrutura , Microscopia Confocal , Microscopia Eletrônica de Varredura , NADPH Desidrogenase/metabolismo , NADPH Desidrogenase/farmacologia , Neurônios Nitrérgicos/ultraestrutura , Serotonina/imunologia , Serotonina/farmacologia
8.
Tissue Cell ; 36(3): 189-95, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15140596

RESUMO

The pattern of muscles in the actively swimming predatory rotifer Asplanchnopus multiceps is revealed by staining with tetramethyl-rhodamine isothiocyanate (TRITC)-labelled phalloidin and confocal scanning laser microscopy (CSLM). The major components of the musculature are: prominent semicircular muscles of the corona; paired lateral, dorsal and ventral retractors in the trunk; a network of six seemingly complete circular muscles and anastomosing longitudinal muscles in the trunk; two short foot retractors, originating from a transverse muscle in the lower third of the trunk. The sphincter of the corona marks the boundary between the head and the trunk. The muscular patterns in rotifers with different lifestyles differ clearly, therefore, the muscular patterns seem to be determined by the mode of locomotion and feeding behaviour.


Assuntos
Microscopia de Fluorescência/métodos , Músculos/citologia , Músculos/fisiologia , Faloidina/análise , Rotíferos/citologia , Rotíferos/fisiologia , Animais , Comportamento Alimentar/psicologia , Locomoção/fisiologia , Microscopia Confocal , Faloidina/química , Comportamento Predatório
9.
Parasitology ; 126(Pt 6): 585-90, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12866797

RESUMO

The activity of neuronal nitric oxide synthase (nNOS) in homogenates of adult Fasciola hepatica was measured by the direct radiometric assay of the production of L-[3H]citrulline. This is the first radiometric study of the activity of nNOS in a fluke. The effect of arginase was tested. In the presence of L-valine, which is an inhibitor of arginase, the formation of L-[3H]citrulline decreased from 12% to 38%, depending on the time of incubation. This means that the arginase activity in the worm is high, and has to be taken into consideration when measuring the activity of nNOS. When co-factors, such as H4B, and NADPH, were omitted the formation of L-[3H]citrulline decreased significantly (29%). The effects of several nNOS inhibitors were tested. N(omega)-nitro-L-arginine (L-NAME), aminoguanidine and S-methyl-L-thiocitrulline added at a concentration of 1 mM inhibited the L-[3H]citrulline formation by 28%, 15% and 14%, respectively. Chelation of Ca2+ with 1 mM EGTA resulted in a 40% decrease in the formation of L-[3H]citrulline. These results indicate the presence of nNOS activity in homogenates of F. hepatica.


Assuntos
Citrulina/análogos & derivados , Fasciola hepatica/enzimologia , Óxido Nítrico Sintase/análise , Tioureia/análogos & derivados , Animais , Arginase/antagonistas & inibidores , Arginase/metabolismo , Bovinos , Citrulina/biossíntese , Citrulina/farmacologia , Inibidores Enzimáticos/farmacologia , Guanidinas/farmacologia , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Radiometria , Tioureia/farmacologia , Valina/farmacologia
10.
Peptides ; 23(11): 2053-61, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12431744

RESUMO

The use of well-characterized antibodies raised to neuronal signal substances and their application through immunocytochemistry and confocal scanning laser microscopy has revolutionized studies of the flatworm nervous system (NS). Data about flatworm neuropeptides and the spatial relationship between neuropeptides and other neuronal signal substances and muscle fibers are presented. Neuropeptides form a large part of the flatworm NS. Neuropeptides are especially important as myoexcitatory transmitters or modulators, controlling the musculature of the attachment organs, the stomatogastric and the reproductive systems.


Assuntos
Neuropeptídeos/isolamento & purificação , Platelmintos/metabolismo , Acetilcolina/metabolismo , Animais , Neuropeptídeos/metabolismo , Filogenia , Platelmintos/classificação , Platelmintos/ultraestrutura , Serotonina/metabolismo
11.
Tissue Cell ; 34(5): 365-74, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12270263

RESUMO

In order to broaden the information about the organisation of the nervous system in the Plathelminthes, an immunocytochemical (ICC) study of the free-living flatworm Castrella truncata (Dalyellioida) has been performed. This is the first time a representative of the taxon Rhabdocoela has been studied with the ICC technique. Antibodies to 5-HT and FMRF-amide and confocal scanning laser microscope were used. 5-HT and FMRF-amide immunoreactivity was observed in the neuropile of the brain, in the cerebral neurones, in the three pairs of longitudinal nerve cords and the adjoining neurones, in the pharyngeal nerve ring and in twelve neurones associated with the pharynx. 5-HT and FMRF-amide immunoreactivity occurs in separate sets of neurones. Only FMRF-amide immunoreactivity was observed in a peculiar ellipse-shaped structure in the brain, and in the genital plexus. The type of orthogon is discussed. Staining of the muscular system with TRITC conjugated phalloidin revealed muscle patterns that have not been described previously.


Assuntos
Músculos/citologia , Sistema Nervoso/citologia , Platelmintos/citologia , Animais , Encéfalo/citologia , Encéfalo/metabolismo , FMRFamida/metabolismo , Gânglios dos Invertebrados/citologia , Gânglios dos Invertebrados/metabolismo , Genitália Masculina/citologia , Genitália Masculina/inervação , Genitália Masculina/metabolismo , Imuno-Histoquímica , Masculino , Microscopia Confocal , Células Musculares/citologia , Células Musculares/metabolismo , Músculos/metabolismo , Sistema Nervoso/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Faloidina , Faringe/citologia , Faringe/metabolismo , Platelmintos/metabolismo , Serotonina/metabolismo
12.
Science ; 293(5535): 1663-6, 2001 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-11533491

RESUMO

The developmental signaling functions of cell surface heparan sulfate proteoglycans (HSPGs) are dependent on their sulfation states. Here, we report the identification of QSulf1, the avian ortholog of an evolutionarily conserved protein family related to heparan-specific N-acetyl glucosamine sulfatases. QSulf1 expression is induced by Sonic hedgehog in myogenic somite progenitors in quail embryos and is required for the activation of MyoD, a Wnt-induced regulator of muscle specification. QSulf1 is localized on the cell surface and regulates heparan-dependent Wnt signaling in C2C12 myogenic progenitor cells through a mechanism that requires its catalytic activity, providing evidence that QSulf1 regulates Wnt signaling through desulfation of cell surface HSPGs.


Assuntos
Padronização Corporal , Proteoglicanas de Heparan Sulfato/metabolismo , Músculos/embriologia , Proteínas Proto-Oncogênicas/metabolismo , Codorniz/embriologia , Transdução de Sinais , Células-Tronco/metabolismo , Sulfatases/metabolismo , Proteínas de Peixe-Zebra , Sequência de Aminoácidos , Animais , Células CHO , Membrana Celular/metabolismo , Células Cultivadas , Clonagem Molecular , Técnicas de Cocultura , Cricetinae , Embrião não Mamífero/metabolismo , Desenvolvimento Embrionário , Proteínas Hedgehog , Heparina/metabolismo , Heparina/farmacologia , Heparitina Sulfato/metabolismo , Dados de Sequência Molecular , Músculos/citologia , Músculos/metabolismo , Mutação , Proteína MyoD/genética , Proteína MyoD/metabolismo , Oligonucleotídeos Antissenso , Proteínas Recombinantes de Fusão/metabolismo , Alinhamento de Sequência , Somitos/metabolismo , Sulfatases/química , Sulfatases/genética , Transativadores/genética , Transativadores/metabolismo , Transfecção , Proteínas Wnt
13.
J Comp Neurol ; 429(1): 71-9, 2001 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11086290

RESUMO

This is the first detailed description of the nitrergic nervous system in a fluke. In this study, the authors analysed the distribution of the nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) reactivity in neuronal and nonneuronal tissues of the adult fluke Fasciola hepatica and compared this with the distribution of the musculature using tetramethylrhodamine isothiocyanate-phalloidin. To assess the correlation between the number of muscle cells in different parts of the fluke and the NADPH-d-stained cells, the nuclei were stained with Hoechst 333 42, which is specific for chromatin. The spatial relation between the NADPH-d-positive nerves and the 5-hydroxytryptamine (serotonin; 5-HT)-immunoreactive (-IR) and GYIRFamide-IR nervous elements was also examined. The methods complement each other. NADPH-d-positive staining occurs in both in neuronal tissue and nonneuronal tissue. Large, NADPH-d-stained neurones were localised in the nervous system. The oral and ventral suckers are innervated with many large NADPH-d-stained neurones. In addition, the NADPH-d staining reaction follows closely the muscle fibres in both the suckers, in the body, and in the ducts of the reproductive organs. The presence of NADPH-d activity along muscle fibres in F. hepatica and in other flatworms supports a possible myoinhibitory role for nitric oxide. Neuronal nitric oxide synthase in flatworms may form a novel drug target, which would facilitate the development of a novel anthelminthic.


Assuntos
Sistema Nervoso Central/metabolismo , Fasciola hepatica/citologia , Fasciola hepatica/metabolismo , Fibras Musculares Esqueléticas/metabolismo , NADPH Desidrogenase/metabolismo , Neurônios/metabolismo , Neuropeptídeos/metabolismo , Oligopeptídeos/metabolismo , Serotonina/metabolismo , Animais , Sistema Nervoso Central/citologia , Gânglios dos Invertebrados/citologia , Gânglios dos Invertebrados/metabolismo , Genitália/citologia , Genitália/metabolismo , Fibras Musculares Esqueléticas/citologia , Fibras Nervosas/metabolismo , Fibras Nervosas/ultraestrutura , Neurônios/citologia , Faringe/citologia , Faringe/metabolismo
14.
Parasitology ; 121 ( Pt 4): 441-53, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11072908

RESUMO

The nervous system of young and adult Amphilina foliacea was studied with immunocytochemical, electron microscopical and spectrofluorometrical methods. The general neuroanatomy is described in detail. New data on the structure and development of the brain were obtained. The 5-HT and GYIRFamide-immunoreactivities occur in separate sets of neurones. The innervation of the reproductive organs is described. The fine structure of 2 types of neurones in the CNS, a sensory neurone, a 'glial' cell type, the neuropile and the synapses are described. The level of 5-HT varies between 0.074 and 0.461 microg/g wet weight. This is the first detailed study of the nervous system of A. foliacea. Earlier data on the structure of the nervous system in A. foliacea published in Russian are introduced into the discussion. The study provides data that can be used when considering the phylogenetic position of Amphilinidea.


Assuntos
Sistema Nervoso/ultraestrutura , Platelmintos/ultraestrutura , Animais , Imuno-Histoquímica/veterinária , Microscopia Eletrônica/veterinária , Neuropeptídeos/análise , Oligopeptídeos/análise , Serotonina/análise , Espectrometria de Fluorescência/veterinária
15.
Parasitol Res ; 86(9): 717-23, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11002978

RESUMO

The ultrastructure of two types of secretory glands in the scolex of preadults of Proteocephalus longicollis is described for the first time in the present report. The gland cells contain extensive cisternae of granular endoplasmic reticulum and Golgi complexes, which participate in the production of secretory globules. Type I scolex glands produce electron-dense globules of various size. The secretory globules enter the secretory canal, openings of which were not observed in the preadults. The secretory product of type I was found at the inner sucker surface and in the tegument of the sucker edges. In addition, electron-dense globules in adult worms are secreted via an eccrine mechanism. Type II scolex glands are characterized by secretory globules of lower electron density and occur mainly in preadults. The electron-lucent, membrane-bound secretory globules are transported via microtubule-lined ducts opening to the exterior at the tegumental surface. Secretory globules of type II are released by an eccrine process.


Assuntos
Cestoides/ultraestrutura , Glândulas Écrinas/ultraestrutura , Animais , Cestoides/crescimento & desenvolvimento , Glândulas Écrinas/crescimento & desenvolvimento , Microscopia Eletrônica , Salmonidae/parasitologia , Vesículas Secretórias/ultraestrutura
16.
Parasitology ; 120 ( Pt 1): 91-5, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10726270

RESUMO

The free radical nitric oxide (NO) is a neuronal messenger which is synthesized from L-arginine and O2 by nitric oxide synthase (NOS). In the synthesis NO and L-citrulline are produced in a stoichiometric 1:1 relation. The activity of NOS was analysed in homogenates of the rat tapeworm Hymenolepis diminuta by measuring the formation of L-[3H]citrulline after incubation with L-[3H]arginine. The nature of NOS in H. diminuta was determined by studying the effect of 3 types of NOS inhibitors: (1) L-NAME, (2) EGTA, (3) 7-nitro-indazole. All inhibitors caused a significant but not complete reduction in the formation of L-[3H]citrulline. The results are discussed against the background of nerve cells and fibres positive for NADPH-diaphorase staining in H. diminuta.


Assuntos
Hymenolepis/enzimologia , Óxido Nítrico Sintase/química , Óxido Nítrico/biossíntese , Animais , Quelantes/química , Citrulina/análise , Citrulina/biossíntese , Ácido Egtázico/química , Inibidores Enzimáticos/química , Indazóis/química , NG-Nitroarginina Metil Éster/química , Ratos , Ratos Wistar , Contagem de Cintilação
17.
Parasitol Res ; 86(2): 89-95, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10685838

RESUMO

The ultrastructure of five types of presumed sensory receptors in the scolex of preadults of Proteocephalus longicollis is described. Two types of nonciliate sensory receptors are situated on the inner surface of the lateral sucker. They differ from each other in the shape, presence, or absence of a large rootlet, electron-dense collars, desmosomes, microtubules, and/or vesicles. In addition, three types of ciliate sensory receptors are found along the edges of the lateral suckers. They can be differentiated by the length of the cilium, by the number of electron-dense collars (one or two), and by types of vesicles. Four types of vesicles were found inside the ciliate sensory receptors. One type of ciliate sensory receptor occurring in preadults differs markedly from any of the sensory receptors previously described in adult P. longicollis.


Assuntos
Cestoides/ultraestrutura , Células Receptoras Sensoriais/ultraestrutura , Animais , Cílios/ultraestrutura , Microscopia Eletrônica
18.
Tissue Cell ; 32(5): 358-65, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11201275

RESUMO

The taxa Nemertodermatida and Acoela have traditionally been considered closely related and classified as sister groups within the Acoelomorpha Ehlers 1984 (Platyhelminthes). Recent molecular investigations have questioned their respective position. In this study, the 5-HT and FMRFamide immunoreactivity (IR) in the nervous system of two nemertodermatids, Nemertoderma westbladi and Meara stichopi, is described. The 5-HT immunoreactive pattern differs in the two nemertodermatids studied. In M. stichopi, two loose longitudinal bundles of 5-HT-immunoreactive fibres and an basi-epidermal nerve net were observed. In N. westbladi the 5-HT-IR shows a ring-shaped commissural structure, different from the commissural brain of acoels. In both nemertodermatids, FMRFamide immunoreactive nerve fibres followed the 5-HT-immunoreactive fibres. It is demonstrated that the Nemertodermatida have neither a 'commissural brain' structure similar to that of the Acoela, nor a 'true', ganglionic brain and orthogon, typical for other Platyhelminthes. The question of the plesiomorphic or apomorphic nature of the nervous system in Nemertodermatida cannot yet be answered. The neuroanatomy of the studied worms provides no synapomorphy supporting the taxon Acoelomorpha.


Assuntos
FMRFamida/biossíntese , Platelmintos/metabolismo , Platelmintos/fisiologia , Serotonina/biossíntese , Animais , Anticorpos/metabolismo , FMRFamida/imunologia , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Modelos Biológicos , Sistema Nervoso/metabolismo , Platelmintos/classificação , Serotonina/imunologia , Especificidade da Espécie
19.
Int J Parasitol ; 29(5): 787-93, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10404277

RESUMO

In order to test the role of nitric oxide in flatworms, Mesocestoides vogae tetrathyridia were incubated together with L-arginine, which is the substrate for nitric oxide synthesis, or with NG-nitro-L-arginine, which is an irreversible inhibitor of nitric oxide synthase. Normally, tetrathyridia attach to each other with the aid of their suckers, forming clusters. The rate of cluster formation was followed during the incubations. L-Arginine stimulated, and NG-nitro-L-arginine clearly inhibited, the cluster formation. This is the first time that an effect of nitric oxide has been observed in a flatworm. In addition, the pattern of the NADPH-diaphorase histochemical reaction in the nervous system and the pattern of F-actin filaments in the musculature stained with TRITC-labelled phalloidin were studied. NADPH-d staining occurred in the brain and the main nerve cords but also followed the muscle fibres stained with phalloidin. The pattern of the NADPH-d reaction was compared with that of 5-HT immunoreactivity. The implications of the results are discussed in relation to the background of data on neuronal signal substances in M. vogae.


Assuntos
Proteínas de Helminto/análise , Mesocestoides/química , NADPH Desidrogenase/análise , Animais , Arginina/metabolismo , Encéfalo/metabolismo , Proteínas de Helminto/metabolismo , Histocitoquímica , Mesocestoides/efeitos dos fármacos , Mesocestoides/fisiologia , Camundongos , Microscopia Confocal , Fibras Musculares Esqueléticas/metabolismo , NADPH Desidrogenase/metabolismo , Óxido Nítrico/biossíntese , Óxido Nítrico/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Nitroarginina/metabolismo , Nitroarginina/farmacologia
20.
Parasitology ; 117 ( Pt 3): 283-92, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9774794

RESUMO

A new category of signalling molecules--transmitter gases--has appeared. Nitric oxide (NO) is generated by nitric oxide synthase (NOS) and diffuses as a short-lived transcellular messenger through the plasma membrane. NADPH-diaphorase (NADPH-d) is a marker enzyme for NO-producing neurons. In this study the pattern of NADPH-d stained neurons in Diphyllobothrium dendriticum is described and compared to the pattern of aminergic and peptidergic neuronal elements and to that of the musculature stained with TRITC-labelled phalloidin. NADPH-d staining was observed in neurons in the bilobed brain and along the 2 main nerve cords and in nerve fibres close to the body musculature and the musculature of the reproductive ducts, the walls of the testicular follicles and in sensory endings in the tegument. The NADPH-d staining reaction and the 5-HT or FMRFamide immunoreactivities occur in separate sets of neurons.


Assuntos
Diphyllobothrium/fisiologia , NADPH Desidrogenase/química , Animais , Sistema Nervoso Central/química , Cricetinae , Corantes Fluorescentes/química , Imuno-Histoquímica , Microscopia Confocal , Microscopia de Fluorescência , Músculos do Pescoço/química , Neurônios/química , Nitroazul de Tetrazólio/química , Sistema Nervoso Periférico/química , Faloidina/química , Coelhos , Rodaminas/química , Salmonidae
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