Morphology and occurrence of two epibiotic marine gomphonemoid diatoms in China

Nova Hedwigia ◽  
2020 ◽  
Vol 111 (3) ◽  
pp. 271-285
Author(s):  
Lang Li ◽  
Chang-Ping Chen ◽  
Jia-Wei Zhang ◽  
Jun-Rong Liang ◽  
Ya-Hui Gao
Keyword(s):  
Electron Microscopy ◽  
Light And Electron Microscopy ◽  
First Record ◽  
South Yellow Sea ◽  
Epiphytic Diatoms ◽  
Original Species ◽  
The South Yellow Sea ◽  
Basic Features ◽  
Species Descriptions

Gomphonemoid diatoms exist in both freshwater and marine environment, but marine gomphonemoid taxa are morphologically different from Gomphonema. Although the marine gomphonemoid group has been expanded with many new taxa in recent years, only the genus Gomphonemopsis was described from Chinese seas. The present study reports on species diversity and classification of marine epiphytic diatoms on seaweeds and epizoic diatoms on animals collected from several stations in the South Yellow Sea and East China Sea. Two marine gomphonemoid diatoms, Pseudogomphonema kamtschaticum and Gomphoseptatum aestuarii, were observed and identified by light and electron microscopy, representing the first record in China of these two species and genera. Our observations matched the basic features of original species descriptions. Except that we observed in P. kamtschaticum showed various areolae shapes (e. g., slit-like, "I"-like, "C"-like and circular), and ornamented macroareolae with small warts were observed in G. aestuarii. Both P. kamtschaticum and G. aestuarii were epiphytic on the seaweed Sargassum hor neri, and P. kamtschaticum was found as epizoic on an ophiuroid species of the Ophiura genus. Therefore, we have increased the records of and knowledge about marine gomphonemoid diatoms to three genera with four species in China, including Gomphonemopsis.

scholarly journals First record of the entomopathogenic protist, Mattesia dispora (Neogregarinorida: Lipotrophidae) of the Mediterranean flour moth, Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) in Turkey

2019 ◽  
Vol 29 (1) ◽  
Author(s):  
Mustafa Yaman ◽  
Kâbire Funda Acar ◽  
Renate Radek
Keyword(s):  
Electron Microscopy ◽  
Fat Body ◽  
Light And Electron Microscopy ◽  
First Record ◽  
Giemsa Stain ◽  
Ephestia Kuehniella ◽  
Life Stages ◽  
Oocyst Wall ◽  
Lepidoptera Pyralidae ◽  
Ultrastructural Characteristics

AbstractThe present study is the first record of a natural neogregarine infection of Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) in Turkey. The infection occurs in the fat body and hemolymph of the larvae. Typical fresh navicular oocysts of the pathogen were 12.1–16.2 μm in length and 5.9–8.5 in width (n = 50). Oocysts stained with Giemsa stain measured 11.7–14.2 μm in length and 5.9–8.5 μm in width. Polar plugs were recognizable using light and electron microscopy. The oocyst wall is quite thick, measuring 460 to 560 nm. Each oocyst contains 8 sporozoites. The described neogregarine has typical characteristics of members of the genus Mattesia (Family Lipotrophidaeorder Neogregarinorida) and shows similarities with Mattesia dispora in morphological and ultrastructural characteristics. The occurrence of the pathogen in different life stages of E. kuehniella was also studied. Total infection was observed as 66.98% in the investigated samples. The pathogen caused different infection levels in the larvae, pupae, and adults of the E. kuehniella, 57.06, 85, and 3.17%, respectively.

Menzbieria chalcographi, a new neogregarine pathogen of the great spruce bark beetle, Dendroctonus micans (Kugelann) (Curculionidae, Scolytinae)

2012 ◽  
Vol 57 (3) ◽  
Author(s):  
Mustafa Yaman ◽  
Renate Radek
Keyword(s):  
Electron Microscopy ◽  
Biological Control ◽  
Bark Beetle ◽  
Light And Electron Microscopy ◽  
First Record ◽  
Dendroctonus Micans ◽  
Male And Female ◽  
Spruce Bark Beetle ◽  
Spruce Bark ◽  
Life Cycle Stages

AbstractThis study concerns a new neogregarine parasitic in the great spruce bark beetle Dendroctonus micans (Kugelann) (Curculionidae, Scolytinae). The rate of infection was high, reaching 27.3%. There was no difference in the rate of infection of male and female beetles. The life-cycle stages of the pathogen were described by light and electron microscopy. Each gametocyst of the neogregarine included 8–16 actinocephalid oocysts measuring 11.19 ± 0.42 × 4.99 ± 0.25 μm. The described pathogen has the typical characteristics of members of the genus Menzbieria within the order Neogregarinida and it was identified as Menzbieria chalcographi. This is the first record of an infection of D. micans by M. chalcographi. Possibly, this pathogen could be useful for the biological control of this destructive bark beetle.

scholarly journals Diversity and Toxicity of the Genus Coolia Meunier in Brazil, and Detection of 44-methyl Gambierone in Coolia tropicalis

Toxins ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 327
Author(s):  
Carlos Eduardo Junqueira de Azevedo Tibiriçá ◽  
Manoella Sibat ◽  
Luciano Felício Fernandes ◽  
Gwenaël Bilien ◽  
Nicolas Chomérat ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Phylogenetic Analyses ◽  
Light And Electron Microscopy ◽  
First Record ◽  
Artemia Salina ◽  
Brazilian Coast ◽  
Species Definition ◽  
Benthic Dinoflagellates

Coolia is a genus of marine benthic dinoflagellates which is widely distributed in tropical and temperate zones. Toxicity has been reported in selected Coolia species, although the identity of causative compounds is still controversial. In this study, we investigated the taxonomical and toxicological aspects of Coolia species from Brazil. Since light- and electron microscopy-based morphology was not enough to distinguish small-celled species, ITS and LSU D1-D3 phylogenetic analyses were used for species definition. Cultures of Coolia palmyrensis and Coolia santacroce were established from samples collected along the northeastern Brazilian coast, the first record of both species in South Atlantic waters. Cultures of Coolia malayensis and Coolia tropicalis were also established and exhibited acute in vivo toxicity to adults of Artemia salina, while C. palmyrensis and C. santacroce were non-toxic. The presence of 30 yessotoxin analogues, 7 metabolites of Coolia and 44 Gambierdiscus metabolites was screened in 14 strains of Coolia. 44-methyl gambierone (formerly referred to as MTX3) and a new isomer of this compound were detected only in C. tropicalis, using both low- and high-resolution LC-MS/MS. To our knowledge, this is the first report of gambierone analogues in dinoflagellates other than Gambierdiscus; the role of C. tropicalis in ciguatera poisoning thus deserves to be considered in further investigations.

Electron Microscopy of Carcinomas of the Lung

1974 ◽  
Vol 32 ◽  
pp. 16-17
Author(s):  
B. Mackay ◽  
M. Mandavia ◽  
J. M. Lukeman ◽  
C. F. Mountain
Keyword(s):  
Electron Microscopy ◽  
Poor Prognosis ◽  
Light And Electron Microscopy ◽  
Malignant Neoplasm ◽  
Therapeutic Modalities ◽  
The Poor ◽  
Diagnosis And Classification ◽  
Methods Of Treatment ◽  
Insight Into

Carcinoma of the lung is the most common malignant neoplasm in males and the incidence continues to rise. The inadequacy of current methods of treatment is reflected in the poor prognosis: only 5% of patients survive for more than five years following diagnosis.In order to assess the effectiveness of new therapeutic modalities, accurate pathologic diagnosis is essential, and it is recognized that a proportion of these tumors can not be accurately classified by light microscopy alone. We have now studied over one hundred lung carcinomas with correlated light and electron microscopy, and our findings indicate that electron microscopy can be an invaluable aid in the diagnosis and classification of the tumors. Study of the fine structure of the tumor cells can provide the basis for a more precise classification than is currently used in clinical studies, and additionally give insight into problems of histogenesis.

Cytological study of Сhloromonas typhlos (Chlamydomonadaceae, Chlorophyta) from North-Western Russia

2017 ◽  
Vol 51 ◽  
pp. 5-11 ◽  
Author(s):  
O. N. Boldina
Keyword(s):  
Electron Microscopy ◽  
Cytological Study ◽  
Light And Electron Microscopy ◽  
First Record ◽  
Ultrastructural Level ◽  
North Western

The strain of biflagellated green monad, selected from the specimen gathered in the Novgorod Region was studied by light and electron microscopy. The species was identified on the base of coincidence of the majority of specific light and ultrastructural signs revealed in both the strain SAG 26.86 of Chloromonas typhlos (Gerloff) Matsuzaki et al. and in studied strain. On LM level the cells are ellipsoid, some asymmetric, 12–17 μm long, 8–13 μm wide, with an apical, hardly distinguished hemispherical papilla flattened on the top. Chloroplast parietal, cup-shaped, thickened on one side, with big lobes, irregular incisions and fissures on the surface. These and other features are characteristic of the type and the studied strain of C. typhlos, excluding stigma observed in the studied strain only. On the ultrastructural level, large thylakoid packs, similar with chloroplast thylakoids, were observed in pyrenoids of both strains of C. typhlos. The detected pyrenoid type was never discovered in chlamydomonads earlier. It is the first record of C. typhlos for the Novgorod Region and the whole Russia, and adds the list of «bloom-forming» species. The strain was deposited in the collection of microalgae strains in the Institute of Biology of Komi Scientific Centre under the name SYKOA Ch-063-17.

scholarly journals THE FORMATION OF THE PRIMARY ENVELOPE DURING OOCYTE DIFFERENTIATION IN TELEOSTS

1967 ◽  
Vol 35 (1) ◽  
pp. 193-212 ◽  
Author(s):  
Everett Anderson
Keyword(s):  
Electron Microscopy ◽  
Amorphous Material ◽  
Light And Electron Microscopy ◽  
Stage Iv ◽  
Stage I ◽  
Dense Layer ◽  
Granular Component ◽  
Hippocampus Erectus ◽  
Oocyte Differentiation

The differentiation of the primary envelope of oocytes of the seahorse (Hippocampus erectus) and the pipefish (Syngnathus fuscus) has been investigated by techniques of light- and electron microscopy. The developing oocytes have been divided into four stages according to size. Oogonia are designated as stage I; stages II and III are oocytes; stage IV represents mature eggs. The primary envelope which is produced by the oocyte is initially a tripartite structure; for convenience of description, the portions are referred to as zones 1, 2, and 3, respectively. Zone 1 first appears as a homogeneous substance at approximately the middle of the long axis of each microvillus. Zone 2 is immediately beneath zone 1 and consists of an extremely electron-opaque granular component. Zone 3 is subjacent to zone 2; it is the largest and most complex of the three. Zone 3 consists of an amorphous material organized in a reticular-like network. Staining procedures indicate that the envelope is composed of a glycoprotein. Just before the oocyte matures there is a structural alteration in zones 2 and 3. Zone 2 becomes a compact, dense layer and zone 3 becomes multilaminate. Subsequent to these changes, zone 1 degenerates. The classification of egg envelopes is discussed, and comparisons are made between the primary envelope of the teleosts investigated and the primary envelopes of other species.

scholarly journals More than Scales: Evidence for the Production and Exudation of Mucilage by the Peltate Trichomes of Tillandsia cyanea (Bromeliaceae: Tillandsioideae)

Plants ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 763
Author(s):  
Igor Ballego-Campos ◽  
Rafaela C. Forzza ◽  
Elder A. S. Paiva
Keyword(s):  
Electron Microscopy ◽  
Light And Electron Microscopy ◽  
Secretory Activity ◽  
First Record ◽  
Standard Methods ◽  
Dense Cytoplasm ◽  
Functional Aspects ◽  
Histochemical Tests ◽  
Peltate Trichomes ◽  
Mucilage Secretion

Bromeliad scales have been investigated extensively due to their recognition as a key ecological and evolutionary feature of Bromeliaceae. However, much remains unknown about such trichomes and only recently mucilage exudation was described for them in a species of the subfamily Bromelioideae. The present study aimed to investigate the secretion present in inflorescences of Tillandsia cyanea Linden ex K. Koch (Tillandsioideae) to determine whether the scales of this species also produce and release secretions. Samples of young and mature portions of inflorescences were collected and prepared according to standard methods for light and electron microscopy. Anatomical and ultrastructural results indicate that the secretion is produced by the wing portion of typical peltate trichomes on the adaxial surface of bracts. The secretory activity begins in the early stages of trichome expansion and characteristically occurs in cells exhibiting a porous cuticle and dense cytoplasm with numerous mitochondria and dictyosomes. Histochemical tests confirmed mucilage secretion and revealed proteins in the exudate. These data comprise the first record of mucilage exudation by trichomes within Tillandsioideae and indicate that this capacity may be more relevant to bromeliad biology than previously considered. Functional aspects and colleter-like activity are also discussed.

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