Parasites infecting the cultured oyster Crassostrea gasar (Adanson, 1757) in Northeast Brazil

Parasitology ◽  
2015 ◽  
Vol 142 (6) ◽  
pp. 756-766 ◽  
Author(s):  
FERNANDO RAMOS QUEIROGA ◽  
ROGÉRIO TUBINO VIANNA ◽  
CAIRÉ BARRETO VIEIRA ◽  
NATANAEL DANTAS FARIAS ◽  
PATRICIA MIRELLA DA SILVA

SUMMARYThe oyster Crassostrea gasar is a species widely used as food and a source of income for the local population of the estuaries of Northeast Brazil. Perkinsus marinus and Perkinsus olseni are deleterious parasites for oyster farming and were recently detected in Brazil. In this study, a histopathologic survey of the oyster C. gasar cultured in the estuary of the River Mamanguape (Paraíba State) was performed. Adult oysters were collected in December 2011 and March, May, August and October 2012 and processed for histology and Perkinsus sp. identification by molecular analyses. Histopathological analysis revealed the presence of parasitic organisms including viral gametocytic hypertrophy, prokaryote-like colonies, protozoans (Perkinsus sp. and Nematopsis sp.) and metazoans (Tylocephalum sp. and cestodes). Other commensal organisms were also detected (the protozoan Ancistrocoma sp. and the turbellarian Urastoma sp.). The protozoan parasite Perkinsus sp. had the highest overall prevalence among the symbiotic organisms studied (48·9%), followed by Nematopsis sp. (36·3%). The other organisms were only sporadically observed. Only the protozoan Perkinsus sp. caused alterations in the oysters’ infected organs. Molecular analyses confirmed the presence of P. marinus, P. olseni and Perkinsus beihaiensis infecting the oyster C. gasar. This is the first report of P. beihaiensis in this oyster species.

2013 ◽  
Vol 113 (1) ◽  
pp. 96-103 ◽  
Author(s):  
Patricia Mirella da Silva ◽  
Rogério Tubino Vianna ◽  
Cristhiane Guertler ◽  
Liana Pinho Ferreira ◽  
Lucas Nunes Santana ◽  
...  

Parasitology ◽  
2003 ◽  
Vol 126 (4) ◽  
pp. 293-302 ◽  
Author(s):  
E. A. MACINTYRE ◽  
C. G. EARNHART ◽  
S. L. KAATTARI

Perkinsus marinus is responsible for a chronic disease (Dermo) of the Eastern oyster, Crassostrea virginica. In order to simulate the in vivo environment more closely, a chemically defined medium (JL-ODRP-3) was supplemented with tissue homogenate extracts or plasma from oysters possessing varying degrees of susceptibility to P. marinus infection. In media supplemented with extracts from highly susceptible oysters (C. virginica), P. marinus cells secreted elevated amounts of a set of low molecular weight serine proteases (LMP: 30–45 kDa) as assessed by enhanced digestion within gelatin-substrate SDS–PAGE gels. Oyster species of low susceptibility (C. gigas and C. ariakensis) did not exhibit this ability to upregulate P. marinus LMP expression. Oyster extract supplementation also led to pronounced changes in P. marinus cellular morphology, such that the cells were comparable to those observed within naturally infected oysters.


1992 ◽  
Vol 247 ◽  
Author(s):  
T. W. Ebbesen ◽  
K. Tanigaki ◽  
S. Saito ◽  
J. Mizuki ◽  
J. S. Tsai ◽  
...  

ABSTRACTThe surprisingly high Tc for the superconductivity of alkali doped C60 has spurred wide interest in understanding its mechanism [1–7]. We first report the superconductive properties of CsxRbyC60 which has a Tc as high as 33 K when x=2 and y=1 in the feed [4, 5]. SQUID measurements show that in this material the coherence length is 45 A and the penetration depth about 1, 800 A [5]. It has now been proven that the observed increase in the Tc with the size of the alkali dopant is due to the increase in the lattice constant [6]. This is most likely due to the changes in the density of states at the Fermi level. The other important parameter according to BSC theory is the phonon which mediates the electron-electron coupling. In the second part of this paper we present recent results which show that the Tc is indeed strongly influenced by this parameter [7]. The isotope effect is unexpectedly strong on the Tc.


PhytoKeys ◽  
2020 ◽  
Vol 148 ◽  
pp. 51-70
Author(s):  
Takuro Ito ◽  
Chih-Chieh Yu ◽  
Masatsugu Yokota ◽  
Goro Kokubugata

We re-examined the taxonomic status of plants treated as Sedum formosanum (Crassulaceae) from Miyako-jima Island of the Ryukyu Islands, Japan, using morphological comparison and molecular phylogenetic analyses with related species. In morphology, plants from Miyako-jima Island bore a close resemblance to the other plants of S. formosanum, but differed in being perennial, polycarpic, and having lateral axillary branches. Molecular analyses based on ITS of nrDNA and six regions of cpDNA sequencing indicated that the Miyako-jima plants formed a distinct subclade. This subclade was part of a polytomy with three other subclades comprising nine taxa endemic to Taiwan and S. formosanum from other areas, including the type locality. Therefore, we propose and describe the Miyako-jima plants as a new subspecies, Sedum formosanum subsp. miyakojimense.


Check List ◽  
2018 ◽  
Vol 14 (6) ◽  
pp. 1115-1121
Author(s):  
Pamela Sánchez-Vendizú ◽  
Joseph A. Cook ◽  
James Wood ◽  
Jorge Salazar-Bravo

Proechimys pattoni da Silva, 1998 is one of the 3 small-bodied species of Proechimys and its geographic range is only known in western Brazil and eastern and southern Peru. However, based on morphological and molecular analyses, we report P. pattoni from the lowland forest of Bolivia (Pando: Rio Madre de Dios, near San Rosa). This is the first report of P. pattoni in Bolivia and extends its distributional range 315 km to the southeast in the Amazon biogeographic region of Bolivia, representing the southeastern most record. Furthermore, we document the karyotype (2n = 40 / FN = 56) and morphological variation in diagnostic characters.


1972 ◽  
Vol 9 (2) ◽  
pp. 159-163 ◽  
Author(s):  
A. C. Johnstone

Two mastocytomas of the liver of sheep are described. The specimens were obtained during a survey of hepatic neoplasia that was conducted on abattoir-slaughtered sheep. Although tissues other than the liver were not examined, both tumours had metastasised, one to the portohepatic lymph node, and the other intrahepatically. It is believed that this is the first report of mastocytoma in this species.


Author(s):  
Vera Mironova

There are several major benefits foreign fighters, and only foreign fighters, can offer armed groups. They have knowledge and experience that the local population does not have and have connections in the international war industry. Usually they are more dedicated to their goals. Foreigners are better at raising funds in their home communities and thus provide armed groups with additional source of income. Finally, they can be successfully used by armed groups for propaganda purposes. On the other hand, it is much harder for the leaders of an armed group to manage foreigners versus locals. First, foreign fighters often do not speak the local language and are not familiar with the terrain. Second, they could have problems with the locals. Third, their presence in the group could decrease overall group cohesion. Fourth, they could be recruited as spies by foreign intelligence agencies more easily than locals. And finally, foreign fighters often joined the conflict with different motives than those of local fighters, which could lead to differences in combat strategy and tactics.


1983 ◽  
Vol 22 (05) ◽  
pp. 232-236 ◽  
Author(s):  
J. Pardo-Montaner ◽  
O. Caballero-Carpena

The authors have studied by quantification the bone uptake of 99mTc-MDP in femoral head necrosis in order to evaluate in an objective manner conventional scintigraphy, and thus to increase the sensitiveness and efficacy of an exploration for an early diagnosis of these patients. Twenty cases of femoral necrosis have been studied, diagnosed in all cases by histopathological analysis; in twelve of them the process was unilateral and in the other eight bilateral. All explorations were carried out with 99mTc-MDP, a gamma camera and a PDP 11/40 computer for the quantitative study with the obtention of indices relating the activity between the femoral heads and, of these, to a normal vertebra. Quantification in the control group showed that the uptake of the nuclide was similar in both femoral heads and is lower than this in the vertebra. In all cases of unilateral necrosis the abnormal deviations of the indices relating the pathological head to the contralateral head and the lumbar vertebra were significant. In bilateral femoral head necrosis, an increase has been observed in all indices, although only the index relating the contralateral femoral head suspect of a lesion to vertebral activity was statistically significant. The proposed method for quantifying can be carried out easily and is very useful for diagnosing femoral necrosis since it improves the results of a subjective assessment of the scintigraphic image and can earlier detect the abnormal uptake of the lesion.


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