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1.
Braz. j. biol ; 79(2): 174-179, Apr.-June 2019. tab, graf
Article in English | LILACS | ID: biblio-989449

ABSTRACT

Abstract The present study assessed the percentage of survival and metamorphosis of larval stages of Caligus rogercresseyi (Boxshall and Bravo, 2000) nauplius I, nauplius II to and nauplius II to copepodite, conducting bioassays in triplicate with 50 larvae each, nauplius I or nauplius II, at temperature of 12 °C, 15 °C and 18 °C; salinity 20, 23, 25, 2729, 31, 33 and 35 g/L and oxygen saturation with ranges between 30-60%, 90-100% and 190 - 200%. Bioassays were performed in station Quillaipe of Fundación Chile, Puerto Montt, Chile. It is concluded that the temperature is inversely proportional to the time of metamorphosis and survival of the larvae of Caligus rogercresseyi . In salinity is observed that increased this, greater is the percentage of survival and metamorphosis is faster, while the larvae do not survive less than 20g/L. Oxygen saturation ranges indicate that the larvae do not survive at saturations between 30-60%, and it had no differences between 90-100% saturation and 190-200%.


Resumo O presente estudo avaliou a percentagem de sobrevivência e metamorfose dos estádios larvais de Caligus rogercresseyi (Boxshall and Bravo, 2000) nauplio I, nauplio II ae nauplio II a copepodita, realizando bioensaios em triplicado com 50 larvas cada, nauplio I ou nauplio II, À temperatura de 12 °C, 15 °C e 18 °C; Salinidade 20, 23, 25, 2729, 31, 33 e 35 g / L e saturação de oxigénio com variações entre 30-60%, 90-100% e 190-200%. Os bioensaios foram realizados na estação Quillaipe da Fundação Chile, Puerto Montt, Chile. Conclui - se que a temperatura é inversamente proporcional ao tempo de metamorfose e sobrevivência das larvas de Caligus rogercresseyi. Na salinidade observa-se que aumentou esta, maior é a percentagem de sobrevivência e metamorfose é mais rápida, enquanto as larvas não sobrevivem menos de 20g / L. Os intervalos de saturação de oxigénio indicam que as larvas não sobrevivem a saturações entre 30-60% e não têm diferenças entre 90-100% de saturação e 190-200%.


Subject(s)
Animals , Copepoda/physiology , Larva/physiology , Metamorphosis, Biological/physiology , Chile
2.
Dental press j. orthod. (Impr.) ; 23(4): 36-42, July-Aug. 2018. graf
Article in English | LILACS | ID: biblio-953043

ABSTRACT

ABSTRACT To biologically explain why the orthodontic treatment does not induce pulp necrosis and calcific metamorphosis of the pulp, this paper presents explanations based on pulp physiology, microscopy and pathology, and especially the cell and tissue phenomena that characterize the induced tooth movement. The final reflections are as follows: 1) the orthodontic movement does not induce pulp necrosis or calcific metamorphosis of the pulp; 2) there is no literature or experimental and clinical models to demonstrate or minimally evidence pulp alterations induced by orthodontic movement; 3) when pulp necrosis or calcific metamorphosis of the pulp is diagnosed during orthodontic treatment or soon after removal of orthodontic appliances, its etiology should be assigned to concussion dental trauma, rather than to orthodontic treatment; 4) the two pulp disorders that cause tooth discoloration in apparently healthy teeth are the aseptic pulp necrosis and calcific metamorphosis of the pulp, both only induced by dental trauma; 5) the concussion dental trauma still requires many clinical and laboratory studies with pertinent experimental models, to increasingly explain its effects on the periodontal and pulp tissues.


RESUMO Para fundamentar biologicamente por que o tratamento ortodôntico não induz necrose pulpar e metamorfose cálcica da polpa, apresentou-se explicações com base na fisiologia, microscopia e patologia pulpar, bem como, e principalmente, nos fenômenos celulares e teciduais que caracterizam a movimentação dentária induzida. As reflexões finais foram: 1) o movimento ortodôntico não induz necrose pulpar ou metamorfose cálcica da polpa; 2) não há literatura e modelos experimentais e clínicos que comprovem ou minimamente evidenciem alterações pulpares induzidas pelo movimento ortodôntico; 3) quando a necrose pulpar ou metamorfose cálcica da polpa for diagnosticada durante o tratamento ortodôntico ou logo após a remoção dos aparelhos ortodônticos, a sua etiologia deve ser atribuída ao traumatismo dentário do tipo concussão, e não ao tratamento ortodôntico; 4) as duas doenças pulpares que levam ao escurecimento coronário em dentes aparentemente hígidos são a necrose pulpar asséptica e a metamorfose cálcica da polpa, ambas induzidas exclusivamente pelo traumatismo dentário; 5) o traumatismo dentário do tipo concussão requer, ainda, muitos estudos clínicos e laboratoriais, com modelos experimentais pertinentes, para fundamentar cada vez mais os seus efeitos sobre os tecidos periodontais e pulpares.


Subject(s)
Humans , Animals , Orthodontics , Tooth Movement Techniques/adverse effects , Dental Pulp/physiology , Dental Pulp Necrosis , Dental Pulp/pathology , Metamorphosis, Biological/physiology , Necrosis
3.
An. acad. bras. ciênc ; 82(2): 313-321, June 2010. graf, tab
Article in English | LILACS | ID: lil-548412

ABSTRACT

Megalopae of many decapod crab species accelerate their development time to metamorphosis (TTM) when exposed to natural physical and/or chemical cues characteristic of the parental habitat. In the present study, the influence of natural settlement cues on the moulting rates and development TTM in megalopae of the fiddler crab Uca vocator was investigated. The effects of mud from different habitats (including well-preserved and degraded-polluted mangrove habitats) and conspecific adult 'odours' (seawater conditioned with crabs) on the induction of metamorphosis were compared with filtered pure seawater (control). 95 to 100 percent of the megalopae successfully metamorphosed to first juvenile crab stage in all treatments, including the control. However, the development TTM differed significantly among treatments. Settlement cues significantly shortened development, while moulting was delayed in their absence. The fact that megalopae responded to metamorphosis-stimulating cues originating from both adult and non-adult benthic habitats demonstrates that settlement in this species may occur in a wider range of habitats within the mangrove ecosystem, including impacted areas.


Megalopas de muitas espécies de caranguejos decápodes aceleram seu período de desenvolvimento até a metamorfose (TOM) quando são expostas a estímulos naturais físicos e/ou químicos característicos do habitat parental. No presente estudo, a influência de estímulos naturais sobre as taxas de muda e sobre o PDM foi investigada nas megalopas do caranguejo violinista Uca vocator. Os efeitos da (i) lama de diferentes habitats (incluindo habitats de um manguezal bem preservado e de um degradado e poluído) e (ii) 'odores' dos adultos conspecíficos (água do mar acondicionada com caranguejos) sobre a indução da metamorfose foram comparados com (iii) água do mar pura e filtrada (controle). 95 a 100 por cento das megalopas realizaram a metamorfose com sucesso para o primeiro estágio de caranguejo juvenil em todos os tratamentos, incluindo o controle. No entanto, o PDM diferiu significativamente entre os tratamentos. Os estímulos encurtaram significativamente o desenvolvimento, enquanto que a muda foi retardada na ausência deles. O fato de que as megalopas responderam aos estímulos indutores da metamorfose oriundos de ambos os habitats bentônicos dos adultos e de habitats onde eles são ausentes, demonstra que o assentamento nesta espécie pode ocorrer em uma grande variedade de habitats dentro do ecossistema de manguezal, incluindo áreas impactadas.


Subject(s)
Animals , Female , Male , Brachyura/growth & development , Ecosystem , Metamorphosis, Biological/physiology , Odorants , Brachyura/physiology , Cues , Larva/growth & development , Seawater , Time Factors
5.
Braz. j. biol ; 67(2): 309-312, May 2007. ilus, tab
Article in English | LILACS | ID: lil-460003

ABSTRACT

The larval morphology of Hypsiboas leptolineatus was studied. The tadpole has an ovoid body in lateral view, wider than deep; snout rounded with dorsal reniform nostrils; spiracle sinistral with lateral wall attached to body; anal tube dextral; tail fins convex with acuminate tip; oral disc ventral; labial tooth row formula is 2(2)/3(1); moderately developed beaks with serrated jaw sheaths. These external oral features are compared with those of the known tadpoles in the Hypsiboas polytaenius clade. The oral cavity was studied using an electron microscope. Life history aspects are commented.


A morfologia larval de Hypsiboas leptolineatus foi estudada. O girino possui corpo ovóide em vista lateral, mais largo que alto; focinho redondo com narinas dorsais; espiráculo esquerdo, com parede lateral junto ao corpo; tubo anal destro; nadadeiras convexas, com ponta acuminada; disco oral ventral; fórmula dentária 2(2)/3(1); bico córneo moderadamente desenvolvido serrilhado. Estas características externas são comparadas com as dos outros girinos conhecidos do clado Hypsiboas polytaenius. A cavidade oral foi estudada usando microscopia eletrônica. Aspectos de história natural são comentados.


Subject(s)
Animals , Anura/anatomy & histology , Larva/anatomy & histology , Metamorphosis, Biological/physiology , Anura/classification , Anura/growth & development , Brazil , Larva/growth & development , Larva/ultrastructure
6.
J Biosci ; 2007 Mar; 32(2): 309-28
Article in English | IMSEAR | ID: sea-110776

ABSTRACT

The morphological and histochemical features of degeneration in honeybee (Apis mellifera) salivary glands were investigated in 5th instar larvae and in the pre-pupal period. The distribution and activity patterns of acid phosphatase enzyme were also analysed. As a routine,the larval salivary glands were fixed and processed for light microscopy and transmission electron microscopy.Tissue sections were subsequently stained with haematoxylin -eosin,bromophenol blue,silver,or a variant of the critical electrolyte concentration (CEC) method.Ultrathin sections were contrasted with uranyl acetate and lead citrate.Glands were processed for the histochemical and cytochemical localization of acid phosphatase,as well as biochemical assay to detect its activity pattern. Acid phosphatase activity was histochemically detected in all the salivary glands analysed.The cytochemical results showed acid phosphatase in vesicles, Golgi apparatus and lysosomes during the secretory phase and,additionally, in autophagic structures and luminal secretion during the degenerative phase. These findings were in agreement with the biochemical assay. At the end of the 5th instar, the glandular cells had a vacuolated cytoplasm and pyknotic nuclei, and epithelial cells were shed into the glandular lumen.The transition phase from the 5th instar to the pre-pupal period was characterized by intense vacuolation of the basal cytoplasm and release of parts of the cytoplasm into the lumen by apical blebbing; these blebs contained cytoplasmic RNA, rough endoplasmic reticule and, occasionally, nuclear material. In the pre-pupal phase, the glandular epithelium showed progressive degeneration so that at the end of this phase only nuclei and remnants of the cytoplasm were observed.The nuclei were pyknotic,with peripheral chromatin and blebs. The gland remained in the haemolymph and was recycled during metamorphosis. The programmed cell death in this gland represented a morphological form intermediate between apoptosis and autophagy.


Subject(s)
Acid Phosphatase/metabolism , Analysis of Variance , Animals , Apoptosis/physiology , Bees/physiology , Histocytochemistry , Larva/physiology , Metamorphosis, Biological/physiology , Microscopy, Electron, Transmission , Salivary Glands/ultrastructure
7.
Rev. biol. trop ; 53(3/4): 503-513, sept.-dic. 2005. ilus, tab
Article in Spanish | LILACS | ID: lil-451278

ABSTRACT

Embryoniclarval development, and metamorphosis larval time, were studied in the tropical fish Xenomelaniris brasiliensis. Twenty nine sexually mature specimens were used, 16 females (10.86 ± 1.01 cm and 7.63 ± 2.62 g) and 13 males (10.43 ± 0.57 cm and 6.54 ± 1.44 g) which produced gametes through abdominal massage. Fertilized eggs were spherical (1.18 ± 0.44 mm diameter), greenish, transparent, benthonic and vitelusrich; rugose striated chorion with numerous external filaments randomly distributed and abundant oil globules (0.11 ± 0.07 mm diameter). The embryonic development was finished at 26.36 ± 2.03ºC, 39.67 ± 0.58 PSU and pH 8.30 ± 0.10. Larvae (4.56 ± 0.97 mm total length) hatched at 143 hours and 19 minutes, with vitteline sac vestiges and a single oil globule. The larvae were fed on Brachionus plicatilis and Isochrysis galbana. After the second week Artemia nauplii were added and I. galbana maintained. Flexion started 13 days after larvae hatched (6.10 ± 1.54 mm total length) and was completed 32 days later (11.25 ± 1.87 mm total length) with the hipural complex completely developed. In conclusion, X. brasiliensis showed direct larval development and started larval metamorphosis (13.08 ± 2.07 mm total length) to juvenile 40 days after hatching


Se describe el desarrollo embrionario y larval hasta la metamorfosis de Xenomelaniris brasiliensi. Un total de 29 ejemplares sexualmente maduros, 16 hembras (10.86 ± 1.01 cm y 7.63 ± 2.62 g) y 13 machos (10.43 ± 0.57 cm y 6.54 ± 1.44 g), liberaron sus productos sexuales mediante masaje abdominal. Los huevos fértiles fueron esféricos de 1.18 ± 0.44 mm de diámetro, verdosos, translúcidos, bentónicos, ricos en vitelo, corion rugoso y estriado, con numerosos filamentos coriónicos, distribuidos aleatoriamente por toda la superficie externa y numerosas gotas lipídicas con un diámetro de 0.11 ± 0.07 mm. El desarrollo embrionario se realizó a 26.36 ± 2.03 ºC, 39.67 ± 0.58 PSU y pH 8.30 ± 0.10 eclosionando larvas de 4.56 ± 0.97 mm a las 143 hrs: 19 min, con vestigios del saco vitelino y una gota lipídica interna. Las larvas fueron alimentadas diariamente con Brachionus plicatilis e Isochrysis galbana, a partir de la segunda semana se incorporó nauplios de Artemia, manteniendo la adición diaria de I. galbana. A los 13 días después de la eclosión de larvas (6.10 ± 1.54 mm) se inició la flexión, completándose a los 32 días (11.25 ± 1.87 mm) con un complejo hipural completamente desarrollado. Se concluye que X. brasiliensis presentó desarrollo larval directo, iniciándose la metamorfosis de larva (13.08 ± 2.07) a juvenil a los 40 días de edad


Subject(s)
Animals , Male , Female , Fishes/growth & development , Metamorphosis, Biological/physiology , Embryo, Nonmammalian , Fishes/embryology , Larva/growth & development , Time Factors
8.
Rev. biol. trop ; 53(3/4): 561-568, sept.-dic. 2005. tab, ilus, graf
Article in English | LILACS | ID: lil-451283

ABSTRACT

The validity of the published description of Hyla rufitela is questioned because the origin of the described tadpoles does not correspond to the distribution of this species. The present description, based on tadpoles that were hatched from two egg masses from the Caribbean lowland of Costa Rica, includes tadpoles raised to adult frogs to verify the species. The newly described tadpoles differ from the previously described and illustrated ones not only in color but also by its more slender body shape (body height:body length, 0.43:0.47), the more slender tail (% tail length of total length, 69%:63%), the more conspicuous spiracle and its position, as well as by the larger oral disk width (oral disk width:body width, 0.44:~0.33). The young tadpoles continually ingest mud as is typical of bottom feeders. Nevertheless, older larvae feed on plant material like rotting mellow leaves of Piper auritum. The tadpoles metamorphosed between 44 and 114 days (x=80.3 days) under the described breeding conditions


La existencia de dudas sobre la validez de la descripción de las larvas de Hyla rufitela realizada por Duellman en 1970 motivaron una nueva descripción con base en renacuajos criados de dos masas de huevos de H. rufitela de la zona caribeña de Costa Rica. Algunos se criaron hasta la edad adulta para verificar la identidad de la especie. Los renacuajos difieren de la descripción e ilustración original por su color, la esbeltez (proporción entre altura y longitud del cuerpo 0.43 vs. 0.47), la cola más delgada (% longitud de la cola de la longitud total del renacuajo 69% vs. 63%), por la posición y forma conspicua del espiráculo, por el disco oral más ancho (ancho del disco: ancho del cuerpo 0.44 vs. ~ 0.33) y por algunos datos alométricos. Las larvas pequeñas permanecen en el fondo alimentándose con materia orgánica del lodo. Los renacuajos mayores se alimentan de material vegetal en descomposición. En cautiverio las renacuajos terminaron su desarrollo en 44-114 días (promedio 80.3 días)


Subject(s)
Animals , Anura/anatomy & histology , Larva/anatomy & histology , Metamorphosis, Biological/physiology , Anura/growth & development , Costa Rica , Larva/growth & development
9.
Rev. biol. trop ; 53(supl.3): 345-355, dic. 2005. ilus, graf, tab
Article in Spanish | LILACS | ID: lil-454835

ABSTRACT

The red sea urchin Strongylocentrotusfranciscanus (Agassiz 1863) is harvested commercially in Baja California, Mexico, since 1970; however, in the last ten years the capture per unit effort (CPUE) has decreased from 310 kg/fishing unit/day to 120 kg/fishing unit/day. For this reason, actions were taken to develop a culture technology allowing massive production of juveniles for re-stocking natural populations or for growing them commercially. We summarize some of the basic studies and main achievements in this effort. In Baja California, considerably faster larval development (approximately 21 days) has been attained than in the US northwest coast (62 days). Spawning of red sea urchins was routinely induced with KCI while egg fertilization was performed using a 100,000-sperm/ml solution. Six microalgae species were tested and Rhodomonas sp. produced the best larval development. The mean survival rate at the end of the larval period was 25%, but results varied widely with bactch. From the feed ratios tested, best results were obtained using 7000 cel/ml during the first week of larval development, followed by 10,000 cel/ml during the second and 15,000 cel/ml during the third week. KCl proved the most consistent metamorphic inducer, regularly yielding metamorphosis percentages higher than 90%. Metamorphosis was considered complete when the functional jaw that juveniles use for first benthic feeding appeared (as soon as 20 days after induction). With this method several thousands of red sea urchin juveniles were produced. They reached up to 1.5 mm in size during the first 50 days of culture after metamorphosis, showing the great potential for mass production of this species in the laboratory


Subject(s)
Humans , Animals , Male , Aquaculture/methods , Ovum/growth & development , Reproduction/physiology , Strongylocentrotus/growth & development , Fertilization , Larva/growth & development , Mexico , Metamorphosis, Biological/physiology , Spermatozoa/physiology
10.
Ciênc. cult. (Säo Paulo) ; 52(1): 59-63, jan.-fev. 2000. ilus
Article in English | LILACS | ID: lil-264431

ABSTRACT

In Melipona quadrifasciata anthidioides a stingless bee, the malpighian tubules (Mt) of the larvae are totally reabsorbed during pupation and replaced by others that will function in the adult. The dye exclusion test shows generalized celular death in the larvall tubules present in prepupae. The results obtained with the acid phosphatase reaction corroborate these findings. Between the end of larval phase and emergence of adult, the insect does not have functional malpighian tubules, but develops waste storaging cells, the urate cells, for nitrogenous waste inactivation. the morphology of degeneration of the larval and the arising of the adult Mt, as well as that of the urate cell on light microscopy are described. The apparent change in the connection point between intestine and malpighian tubules of larva and adult is also discussed.


Subject(s)
Animals , Bees/ultrastructure , Metamorphosis, Biological/physiology , Malpighian Tubules/ultrastructure , Bees/physiology , Acid Phosphatase/metabolism , Larva/physiology , Larva/ultrastructure , Microscopy, Polarization/methods , Pupa/physiology , Pupa/ultrastructure , Malpighian Tubules/physiology , Urate Oxidase/physiology
11.
In. Montenegro Medina, María Angélica; Mena L., Miguel Angel; Illanes Herrero, Julio; Lemus Acuña, David. Embriología humana. Santiago de Chile, Universidad de Chile. Facultad de Medicina. Departamento de Morfología Experimental, 1996. p.131-44, ilus.
Monography in Spanish | LILACS | ID: lil-185320
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