scholarly journals Embryogenesis of an Invertebrate Lymphoid Organ: The Asterina Gibbosa Axial Organ (Asterids, Echinodermata)

2020 ◽  
pp. 1-2
Keyword(s):  
Ventral Side ◽  
Sensu Stricto ◽  
Lymphoid Organ ◽  
Axial Complex ◽  
Axial Organ ◽  
Stone Canal

The metamerization of the coelom leads to the axial complex genesis. Mesodermic cells appear besides the stone canal (larva 12 days old): they constitute the axial organ (AO) which develop, in the ventral side, the oral part (PO). This last part corresponds (sensu stricto) to the ancestral lymphoïd organ.

The starfish axial organ: An ancestral lymphoid organ

1980 ◽  
Vol 4 ◽  
pp. 605-615 ◽  
Author(s):  
M. Leclerc ◽  
C. Brillouet ◽  
G. Luquet
Keyword(s):  
Lymphoid Organ ◽  
Axial Organ

Memoirs: The Reproductive System and Associated Organs of the Brittle-Star Ophiothrix Fragilis

1940 ◽  
Vol s2-82 (326) ◽  
pp. 267-309
Author(s):  
J. B. SMITH
Keyword(s):  
Breeding Season ◽  
Reproductive System ◽  
Body Wall ◽  
The Body ◽  
The Other ◽  
Larval Life ◽  
Free Swimming ◽  
Axial Organ ◽  
The Right ◽  
Stone Canal

1. The organs associated, either directly or indirectly, with reproduction in the Ophiuroidea are the axial organ and related sinuses (axial organ complex), the genital raehis, the gonads (localized expansions of the raehis), the gonoducts, and the genital bursae. 2. Evidence is presented in favour of the view of Fedotov (1924) that the axial organ of Ophiuroids is made up of two closely associated parts each surrounded by its own sinus from the wall of which it is, during development, proliferated. The left axial sinus (aboral in the adult) is derived from the left anterior coelom of the larva, the right axial sinus (oral in the adult) from the madreporie vesicle which itself is a derivative of the right anterior coelom of the larva. 3. The ampulla of the stone canal is continuous with, and is part of, the left axial sinus. 4. An account is given of the morphology and histology of the genital rachis and sinus. 5. Examination of the gonads of female Ophiothrix indicate that the breeding season extends from about March to October and that, during this time, there is periodic emission of ova, probably at monthly intervals. Males, on the other hand, produce sperm all the year round. 6. The genital bursae number two pairs to each interradial pouch. They serve, primarily, as organs of respiration. Special mechanisms, which are described, are concerned in the intake and expulsion of water. 7. The gonads do not discharge their products directly into the genital bursae nor through temporarily formed pores in the body-wall but through specially developed and permanent gonoducts, one to each of the ten gonads. 8. Young specimens found in the genital bursae have attained their position only after a period of free-swimming larval life. After settling and metamorphosing, some of the young individuals crawl into the bursae. 9. As a consequence of the previous observation it is pointed out that the presence of the young within the genital bursae of the adult is by no means an indication of a viviparous habit.

scholarly journals Redescription of Aspidogaster limacoides Diesing, 1834 (Aspidogastrea: Aspidogastridae) from freshwater fishes of northern Germany

2021 ◽  
Vol 120 (10) ◽  
pp. 3405-3416 ◽  
Author(s):  
Jaydipbhai Suthar ◽  
Sarah Al-Jufaili ◽  
Rodney A. Bray ◽  
Marcus Frank ◽  
Stefan Theisen ◽  
...  
Keyword(s):  
Perca Fluviatilis ◽  
Distinct Group ◽  
Rutilus Rutilus ◽  
Ventral Side ◽  
Molecular Data ◽  
Sensu Stricto ◽  
The Body ◽  
Promising Tool ◽  
Scardinius Erythrophthalmus ◽  
Aspidogaster Limacoides

AbstractAspidogaster limacoides Diesing, 1834 (Aspidogastridae) is redescribed based on light and scanning electron microscopy of specimens from the stomach and intestine of Abramis brama, Rutilus rutilus and Scardinius erythrophthalmus (Actinopterygii: Cyprinidae). The fishes were sampled during 2018 and 2019 at Lake Tollense in Mecklenburg-Western Pomerania, Germany. The prevalence of A. limacoides was highest in R. rutilus (61.7%) followed by Scardinius erythrophthalmus (7.7%) and A. brama (2.9%), while it was absent in Perca fluviatilis from the same lake. The following structures of A. limacoides are described for the first time: a depression on the ventral side of the neck, variations in the number and the arrangement of alveoli, numerous pits scattered all over the body surface, the presence of a few papillae-like structures posterior lateral to the mouth, the number of marginal organs represented by openings of exocrine multicellular glands as shown in histology and the subterminal position of the excretory pore. These characters can be used to distinguish three species of Aspidogaster, namely, A. ijimai, A. conchicola and A. limacoides, suggesting that SEM is a useful and promising tool in differentiating Aspidogaster species. Comparison of molecular data of the ITS1-5.8S-ITS2 regions showed a 94% similarity to A. limacoides from the European part of Russia. Phylogenetic analysis showed that the present specimens clustered in the same clade with A. limacoides sensu stricto, forming a distinct group to the exclusion of congeners.

scholarly journals Redefinition of the Dinoflagellate Genus Alexandrium Based on Centrodinium: Reinstatement of Gessnerium and Protogonyaulax, and Episemicolon gen. nov. (Gonyaulacales, Dinophyceae)

2019 ◽  
Vol 2019 ◽  
pp. 1-17 ◽  
Author(s):  
Fernando Gómez ◽  
Luis Felipe Artigas
Keyword(s):  
Phylogenetic Analyses ◽  
Large Subunit ◽  
Ventral Side ◽  
Sensu Stricto ◽  
Alexandrium Tamarense ◽  
Tropical Species ◽  
Rrna Gene ◽  
Apical Pore ◽  
Sister Clade ◽  
The Right

The genus Centrodinium contains oceanic and predominantly tropical species that have received little attention. Three species of Centrodinium were examined using thecal plate dissociation, scanning electron microscopy, and molecular sequences. The apical horn of Centrodinium intermedium and C. eminens is formed by the elongation of the fourth apical plate, and a second apical split into two plates. In C. punctatum two apical plates (2′ and 4′) almost completely encircle the apical pore plate (Po), while the contact with the plate 1′ in the ventral side is much reduced, and the plate 3′ does not reach the Po. Moreover, its left posterior lateral sulcal plate is longer than its right pair, while reversed in the typical Centrodinium spp. The sulcal posterior plate of C. punctatum is located in the left-ventral side below the plates 1′′′ and 2′′′, while the sulcal posterior plate located in the right face below the plates 4′′′ and 5′′′ in the typical Centrodinium spp. Phylogenetic analyses based on the small and large subunit of the rRNA gene showed that Centrodinium spp. and Alexandrium affine/A. gaarderae clustered as a sister clade of the Alexandrium tamarense/catenella/fraterculus groups. The clade of the subgenus Gessnerium, and the clade of the type species of Alexandrium, A. minutum, with four divergent species, clustered in more basal positions. The polyphyly of Alexandrium is solved with the split into four genera: (1) Alexandrium sensu stricto for the species of the clade of A. minutum and four divergent species; (2) the reinstatement of the genus Gessnerium for the species of the clade of A. monilatum; (3) the reinstatement of genus Protogonyaulax for the species of the tamarense/catenella/fraterculus groups, and (4) the new genus Episemicolon gen. nov. for A. affine and A. gaarderae. New combinations in the genera Gessnerium, Protogonyaulax, and Episemicolon are proposed.

scholarly journals Asterias Rubens (Echinoderm): Evidence of Lymphocytes, Lymphokines and Invertebrate Primitive Antibody(IPA).Expected Rôle of Tiedemann’s Bodies

2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Michel Leclerc
Keyword(s):  
Immune Responses ◽  
Lymphoid Organ ◽  
Sea Star ◽  
Asterias Rubens ◽  
Humoral Immune ◽  
Axial Organ

The axial organ is considered as ancestral lymphoïd organ. It contains T and B sea star lymphocytes and Phagocytes. It plays a fundamental rôle in the sea star cell-mediated immune responses and humoral immune ones.Asterids belong to Echinoderma (Invertebrates).An expected rôle of Tiedemann’s bodies is evoked.

scholarly journals Glandular Cells in Sea Star Lymphoïd Organ: Axial Organ Tem Observations

2020 ◽  
pp. 1-2
Author(s):  
Michel Leclerc ◽  
Keyword(s):  
Electron Microscopy ◽  
Neural System ◽  
Lymphoid Organ ◽  
Sea Star ◽  
Axial Organ ◽  
Glandular Cells

We recall, in this work, the presence of an epithelio-neural system in the sea star axial organ and a glandular one. Many vesicles (from 100 to 500 angstroms) with a more or less opaque content in electron microscopy, appear in these last cells

KREATYWNOŚĆ JAKO IMPERATYW I ATRYBUT WSPÓŁCZESNEGO PRZEDSIĘBIORSTWA

2018 ◽  
pp. 41-47
Author(s):  
Cezary Suszyński
Keyword(s):  
Sensu Stricto

Artykuł jest teoretycznym studium wspartym odniesieniami do praktyki zarządzania, którego celem jest przedstawienie argumentacji na rzecz tezy o kreatywności organizacyjnej jako imperatywie i zarazem atrybucie współczesnego przedsiębiorstwa (sensu largo). Obszarem studiów są wybrane teorie ekonomiczne (klasyczna, neoklasyczna, schumpeterowska, instytucjonalna) oraz niektóre koncepcje na gruncie zarządzania strategicznego (strategia jako: wzorzec, zestaw kluczowych kompetencji, zasobów i umiejętności przedsiębiorstwa, przełomowe innowacje, współkreowanie wartości). Analiza uwzględniająca obie perspektywy ujawnia immanentny charakter kreatywności organizacyjnej w procesach wzrostu i rozwoju przedsiębiorstw, zwłaszcza od fazy wykształcenia się zarządzania strategicznego. Wyraźnie rosnąca dynamika zmian (turbulencji) otoczenia przedsiębiorstw skłania je do sięgania po nowe rozwiązania w zakresie idei, koncepcji, zasobów, strategii, modeli biznesu, nadając organizacyjnej kreatywności charakter atrybutu współczesnego przedsiębiorstwa. Dodatkowy wniosek w świetle poczynionych konstatacji co do atrybutowego charakteru kreatywności organizacyjnej wskazuje również jako dyskusyjne spotykane w literaturze przedmiotu określenie "przedsiębiorstwo kreatywne", stosowane w odniesieniu do grupy przedsiębiorstw (sensu stricto) reprezentujących sektory (branże, przemysły) kreatywne. (

Suitability of forms of preparing seeds of Dalbergia miscolobium Benth for exposure to the tetrazolium test / Adequação das formas de preparação de sementes de Dalbergia miscolobium Benth para exposição ao teste de tetrazolium

2017 ◽  
Vol 1 (1) ◽  
Author(s):  
Juliana Martins de Mesquita Matos ◽  
Rosana De Carvalho Cristo Martins ◽  
Valéria Regina Bellotto ◽  
Lilian Gomes da Silva Rocha ◽  
Eloiza Aparecida Barbosa ◽  
...  
Keyword(s):  
Endangered Species ◽  
Filter Paper ◽  
Federal District ◽  
Complete Removal ◽  
Sensu Stricto ◽  
The Other ◽  
Distrito Federal ◽  
Viable Seeds ◽  
Range Test ◽  
Tetrazolium Test

Dalbergia miscolobium or Jacarandá do Cerrado is a species of legume in the Fabaceae family. It occurs in the sensu stricto Cerrado and in the dystrophic cerradão. It shows potential for landscaping and for recovering damaged areas. It is an endangered species and therefore is protected by the law that prevents cut in areas of the Federal District (Decree No. 14.783/93). The purpose of this study was to determine the best procedure to prepare seeds of Dalbergia miscolobium to assess viability in the tetrazolium test. We carried out the following treatments: i) hydration on filter paper at 25 ° C, ii) hydration on filter paper at 25 ° C followed by a cut in the tegument and iii) hydration on filter paper at 25 ° C followed bya complete removal of the tegument. The results were analyzed using analysis of variance and the Tukey range test. The analyzes showed that the best procedure to prepare seeds of Dalbergia miscolobium is the treatment in which there is a hydration followed by the complete removal of the integument. Where 78% of the seeds showed uniform staining, indicating that the seeds analyzed are of good quality. The other treatments, hydration and hydration followed by cutting, showed respectively 35% and 41% of viable seeds. RESUMO A Dalbergia miscolobium ou Jacarandá do Cerrado é uma espécie de leguminosa da família Fabaceae. Ocorre no sentido stricto Cerrado e no cerradão distrófico. Possui potencial para paisagismo e para recuperar áreas degradadas. É uma espécie ameaçada de extinção e, portanto, está protegida pela lei que previne o corte em áreas do Distrito Federal (Decreto 14.783 / 93). O objetivo deste estudo foi determinar o melhor procedimento de prepararação das sementes de Dalbergia miscolobium para serem submetidas à análise de viabilidade pelo teste de tetrazólio. Foram realizados os seguintes tratamentos: i) hidratação em papel de filtro a 25 ° C, ii) hidratação em papel de filtro a 25 ° C seguida de um corte no tegumento e iii) hidratação em papel de filtro a 25 ° C seguido de remoção completa do tegumento. Os resultados foram analisados utilizando-se a análise de variância e o teste de médias de Tukey. As análises mostraram que o melhor procedimento para preparar sementes de Dalbergia miscolobium é o tratamento em que há uma hidratação seguida pela remoção completa do tegumento, onde 78% das sementes apresentaram coloração uniforme, indicando que as sementes analisadas são de boa qualidade. Os demais tratamentos, hidratação e hidratação seguida de corte, mostraram respectivamente 35% e 41% de sementes viáveis.

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