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Sample records for gigantic bivalve alatoconchidae

  1. Pituitary gigantism.

    Science.gov (United States)

    Lu, P W; Silink, M; Johnston, I; Cowell, C T; Jimenez, M

    1992-01-01

    A case of pituitary gigantism resulting from a pituitary adenoma which secreted growth hormone is described. The patient was successfully treated by surgery, which led to the normalisation of endogenous growth hormone secretion. An acceptable final height was achieved with high dose intramuscular testosterone treatment. Images Figure 1 PMID:1520009

  2. Pituitary gigantism.

    OpenAIRE

    Lu, P W; Silink, M; Johnston, I; Cowell, C T; Jimenez, M

    1992-01-01

    A case of pituitary gigantism resulting from a pituitary adenoma which secreted growth hormone is described. The patient was successfully treated by surgery, which led to the normalisation of endogenous growth hormone secretion. An acceptable final height was achieved with high dose intramuscular testosterone treatment.

  3. Partial gigantism

    Directory of Open Access Journals (Sweden)

    М.М. Karimova

    2017-05-01

    Full Text Available A girl with partial gigantism (the increased I and II fingers of the left foot is being examined. This condition is a rare and unresolved problem, as the definite reason of its development is not determined. Wait-and-see strategy is recommended, as well as correcting operations after closing of growth zones, and forming of data pool for generalization and development of schemes of drug and radial therapeutic methods.

  4. AIP mutations and gigantism.

    Science.gov (United States)

    Rostomyan, Liliya; Potorac, Iulia; Beckers, Pablo; Daly, Adrian F; Beckers, Albert

    2017-06-01

    AIP mutations are rare in sporadic acromegaly but they are seen at a higher frequency among certain specific populations of pituitary adenoma patients (pituitary gigantism cases, familial isolated pituitary adenoma (FIPA) kindreds, and patients with macroadenomas who are diagnosed ≤30 years). AIP mutations are most prevalent in patients with pituitary gigantism (29% of this group were found to have mutations in AIP gene). These data support targeted genetic screening for AIP mutations/deletions in these groups of pituitary adenoma patients. Earlier diagnosis of AIP-related acromegaly-gigantism cases enables timely clinical evaluation and treatment, thereby improving outcomes in terms of excessive linear growth and acromegaly comorbidities. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  5. Pulsars: gigantic nuclei

    International Nuclear Information System (INIS)

    Xu, Renxin

    2011-01-01

    What is the real nature of pulsars? This is essentially a question of the fundamental strong interaction between quarks at low-energy scale and hence of the non-perturbative quantum chromo-dynamics, the solution of which would certainly be meaningful for us to understand one of the seven millennium prize problems (i.e., "Yang-Mills Theory") named by the Clay Mathematical Institute. After a historical note, it is argued here that a pulsar is very similar to an extremely big nucleus, but is a little bit different from the gigantic nucleus speculated 80 years ago by L. Landau. The paper demonstrates the similarity between pulsars and gigantic nuclei from both points of view: the different manifestations of compact stars and the general behavior of the strong interaction. (author)

  6. Can bivalve veligers escape feeding currents of adult bivalves?

    NARCIS (Netherlands)

    Troost, K.; Veldhuizen, R.; Stamhuis, E.J.; Wolff, W.J.

    2008-01-01

    While the stock of introduced Pacific oysters (Crassostrea gigas) increased in the Oosterschelde estuary (SW Netherlands), so did the filtration pressure of all bivalve species together. In the same period, stocks of native bivalves declined slightly. The expansion of Pacific oysters in Dutch

  7. Genetics of Gigantism and Acromegaly

    OpenAIRE

    Hannah-Shmouni, Fady; Trivellin, Giampaolo; Stratakis, Constantine A.

    2016-01-01

    Gigantism and acromegaly are rare disorders that are caused by excessive GH secretion and/or high levels of its mediator, IGF-1. Gigantism occurs when excess GH or IGF-1 lead to increased linear growth, before the end of puberty and epiphyseal closure. The majority of cases arise from a benign GH-secreting pituitary adenoma, with an incidence of pituitary gigantism and acromegaly of approximately 8 and 11 per million person-years, respectively. Over the past two decades, our increasing unders...

  8. Recirculation nursery systems for bivalves

    NARCIS (Netherlands)

    Kamermans, P.; Blanco Garcia, A.; Joaquim, Sandra; Matias, Domitilia; Magnesen, Thorolf; Nicolas, J.; Petten, Bruno; Robert, Rene

    2016-01-01

    n order to increase production of bivalves in hatcheries and nurseries, the development of new technology and its integration into commercial bivalve hatcheries is important. Recirculation aquaculture systems (RASs) have several advantages: high densities of the species can be cultured resulting in

  9. Genetics of Gigantism and Acromegaly

    Science.gov (United States)

    Hannah-Shmouni, Fady; Trivellin, Giampaolo; Stratakis, Constantine A.

    2016-01-01

    Gigantism and acromegaly are rare disorders that are caused by excessive GH secretion and/or high levels of its mediator, IGF-1. Gigantism occurs when excess GH or IGF-1 lead to increased linear growth, before the end of puberty and epiphyseal closure. The majority of cases arise from a benign GH-secreting pituitary adenoma, with an incidence of pituitary gigantism and acromegaly of approximately 8 and 11 per million person-years, respectively. Over the past two decades, our increasing understanding of the molecular and genetic etiologies of pituitary gigantism and acromegaly yielded several genetic causes, including multiple endocrine neoplasia type 1 and 4, McCune-Albright syndrome, Carney complex, familial isolated pituitary adenoma, pituitary adenoma association due to defects in familial succinate dehydrogenase genes, and the recently identified X-linked acrogigantism. The early diagnosis of these conditions helps guide early intervention, screening, and genetic counseling of patients and their family members. In this review, we provide a concise and up-to-date discussion on the genetics of gigantism and acromegaly. PMID:27657986

  10. Genetics of gigantism and acromegaly.

    Science.gov (United States)

    Hannah-Shmouni, Fady; Trivellin, Giampaolo; Stratakis, Constantine A

    Gigantism and acromegaly are rare disorders that are caused by excessive GH secretion and/or high levels of its mediator, IGF-1. Gigantism occurs when excess GH or IGF-1 lead to increased linear growth, before the end of puberty and epiphyseal closure. The majority of cases arise from a benign GH-secreting pituitary adenoma, with an incidence of pituitary gigantism and acromegaly of approximately 8 and 11 per million person-years, respectively. Over the past two decades, our increasing understanding of the molecular and genetic etiologies of pituitary gigantism and acromegaly yielded several genetic causes, including multiple endocrine neoplasia type 1 and 4, McCune-Albright syndrome, Carney complex, familial isolated pituitary adenoma, pituitary adenoma association due to defects in familial succinate dehydrogenase genes, and the recently identified X-linked acrogigantism. The early diagnosis of these conditions helps guide early intervention, screening, and genetic counseling of patients and their family members. In this review, we provide a concise and up-to-date discussion on the genetics of gigantism and acromegaly. Published by Elsevier Ltd.

  11. Cerebral gigantism with West syndrome.

    Science.gov (United States)

    Ray, Munni; Malhi, P; Bhalla, A K; Singhi, P D

    2003-07-01

    A case of cerebral gigantism (Sotos syndrome) with West syndrome in a one-year-old male child is reported. The case had a large stature, typical facies and neurodevelopmental delay along with infantile spasms, which were refractory to treatment with valproate and clonazepam.

  12. Cerebral gigantism of hypothalamic origin.

    Science.gov (United States)

    Ranke, M B; Bierich, J R

    1983-04-01

    In five cases of Sotos Syndrome serum somatomedin activities were measured. In two of these cases elevated levels and an increased secretion of growth hormone was observed. In one case (index case) a suspected hypothalamic tumor mass could be excluded, but hydrocephalus with increased intracranial pressure was present. The pathogenesis of gigantism in this syndrome is discussed.

  13. Preoperative embolization of gigantic meningioma

    International Nuclear Information System (INIS)

    Wang Hongsheng; Chen Huaqun; Dong Congsong; Li Wenhui; Dai Zhenyu; Chen Guozhi

    2006-01-01

    Objective: To evaluate the clinical efficacy of preoperative embolization in treatment of patients with gigantic meningioma. Methods: Fourteen cases of gigantic meningioma diameter from 6 to 11 cm were measured by CT and MRI scan. DSA manifested that they are vascularizd meningioma and showed the mainly feeding arteries. We used getation sponge to superselectively embilized the feeding arteries. All tumors were performed surgical excision 3-7 days after the embolization. Results: DSA showed the blood supplies in the tumors in 9 cases were completely blocked, and that in 5 cases were dramatically eliminated. All patients were operated 3-7 days after the embolization. During the operations the bleeding were dramatically decreased and the operation time was shortened compared with those in unembolized cases. It helps us remove the tumors easy and quickly from the attachments. No complication occurred during and after the operations. Conclusion: Preoperative embolization of gigantic meningioma is a useful and relatively safe method in helping surgicaly and completely excised of tumor with significant reduction of blood loss and operation time. (authors)

  14. Pituitary gigantism: Causes and clinical characteristics.

    Science.gov (United States)

    Rostomyan, Liliya; Daly, Adrian F; Beckers, Albert

    2015-12-01

    Acromegaly and pituitary gigantism are very rare conditions resulting from excessive secretion of growth hormone (GH), usually by a pituitary adenoma. Pituitary gigantism occurs when GH excess overlaps with the period of rapid linear growth during childhood and adolescence. Until recently, its etiology and clinical characteristics have been poorly understood. Genetic and genomic causes have been identified in recent years that explain about half of cases of pituitary gigantism. We describe these recent discoveries and focus on some important settings in which gigantism can occur, including familial isolated pituitary adenomas (FIPA) and the newly described X-linked acrogigantism (X-LAG) syndrome. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  15. Cerebral gigantism (Sotos' syndrome) and cataracts.

    Science.gov (United States)

    Yeh, H; Price, R L; Lonsdale, D

    1978-01-01

    A five-year-old girl with cerebral gigantism (Sotos' syndrome) and cataracts is described. Sotos' syndrome, characterized by generalized gigantism with normal endocrine studies has rarely been reported with ocular abnormalities and never with cataracts. It is important to study any child with cataracts for systemic disease.

  16. Galeommatid bivalves from Phuket, Thailand

    DEFF Research Database (Denmark)

    Lützen, Jørgen; Nielsen, Claus

    2005-01-01

    Twenty-seven species of galeommatid bivalves from six genera have been collected at intertidal reef flats near Phuket Marine Biological Center, Thailand (Andaman Sea, Indian Ocean). Fourteen of the species are new to science and a new genus (Nudiscintilla gen. nov.) has been established. The spec......Twenty-seven species of galeommatid bivalves from six genera have been collected at intertidal reef flats near Phuket Marine Biological Center, Thailand (Andaman Sea, Indian Ocean). Fourteen of the species are new to science and a new genus (Nudiscintilla gen. nov.) has been established...... crustacean, the remainder hide under shale, rocks and coral blocks, often in small intra- or interspecific family flocks. The behaviour was also noted for some of the species. It is presumed that galeommatid species go through a lengthy planktonic phase....

  17. Dominant inheritance of cerebral gigantism.

    Science.gov (United States)

    Zonana, J; Sotos, J F; Romshe, C A; Fisher, D A; Elders, M J; Rimoin, D L

    1977-08-01

    Cerebral gigantism is a syndrome consisting of characteristic dysmorphic features, accelerated growth in early childhood, and variable degrees of mental retardation. Its etiology and pathogenesis have not been defined. Three families are presented with multiple affected members. The vertical transmission of the trait and equal expression in both sexes in these families indicates a genetic etiology with a dominant pattern of inheritance, probably autosomal. As in previously reported cases, extensive endocrine evaluation failed to define the pathogenesis of the accelerated growth present in this disorder.

  18. Pituitary Gigantism: A Case Report

    OpenAIRE

    Rana Bhattacharjee; Ajitesh Roy; Soumik Goswami; Chitra Selvan; Partha P Chakraborty; Sujoy Ghosh; Dibakar Biswas; Ranen Dasgupta; Satinath Mukhopadhyay; Subhankar Chowdhury

    2012-01-01

    Objective: To present a rare case of gigantism. Case Report: A 25-year-old lady presented with increased statural growth and enlarged body parts noticed since the age of 14 years, primary amenorrhea, and frontal headache for the last 2 years. She has also been suffering from non-inflammatory low back pain with progressive kyphosis and pain in the knees, ankles, and elbows for the last 5 years. There was no history of visual disturbance, vomiting, galactorrhoea, cold intolerance. She had no si...

  19. Thunderstorm Charge Structures Producing Negative Gigantic Jets

    Science.gov (United States)

    Boggs, L.; Liu, N.; Riousset, J. A.; Shi, F.; Rassoul, H.

    2016-12-01

    Here we present observational and modeling results that provide insight into thunderstorm charge structures that produce gigantic jet discharges. The observational results include data from four different thunderstorms producing 9 negative gigantic jets from 2010 to 2014. We used radar, very high frequency (VHF) and low frequency (LF) lightning data to analyze the storm characteristics, charge structures, and lightning activity when the gigantic jets emerged from the parent thunderstorms. A detailed investigation of the evolution of one of the charge structures by analyzing the VHF data is also presented. The newly found charge structure obtained from the observations was analyzed with fractal modeling and compared with previous fractal modeling studies [Krehbiel et al., Nat. Geosci., 1, 233-237, 2008; Riousset et al., JGR, 115, A00E10, 2010] of gigantic jet discharges. Our work finds that for normal polarity thunderstorms, gigantic jet charge structures feature a narrow upper positive charge region over a wide middle negative charge region. There also likely exists a `ring' of negative screening charge located around the perimeter of the upper positive charge. This is different from previously thought charge structures of the storms producing gigantic jets, which had a very wide upper positive charge region over a wide middle negative charge region, with a very small negative screening layer covering the cloud top. The newly found charge structure results in leader discharge trees in the fractal simulations that closely match the parent flashes of gigantic jets inside and outside the thundercloud. The previously used charge structures, while vital to the understanding of gigantic jet initiation and the role of charge imbalances inside the cloud, do not produce leader discharge trees that agree with observed gigantic jet discharges.Finally, the newly discovered gigantic jet charge structures are formed near the end of a convective pulse [Meyer et al., JGR, 118

  20. Pituitary Gigantism: A Case Report

    Directory of Open Access Journals (Sweden)

    Rana Bhattacharjee

    2012-01-01

    Full Text Available Objective: To present a rare case of gigantism. Case Report: A 25-year-old lady presented with increased statural growth and enlarged body parts noticed since the age of 14 years, primary amenorrhea, and frontal headache for the last 2 years.She has also been suffering from non-inflammatory low back pain with progressive kyphosis and pain in the knees, ankles, and elbows for the last 5 years. There was no history of visual disturbance, vomiting, galactorrhoea, cold intolerance. She had no siblings. Family history was non-contributory.Blood pressure was normal. Height 221 cm, weight 138 kg,body mass index (BMI28. There was coarsening of facial features along with frontal bossing and prognathism, large hands and feet, and small goitre. Patient had severe kyphosis and osteoarthritis of knees. Confrontation perimetry suggested bitemporal hemianopia. Breast and pubic hair were of Tanner stage 1. Serum insulin like growth factor-1 (IGF1 was 703 ng/ml with all glucose suppressedgrowth hormone (GHvalues of >40 ng/ml. Prolactin was 174 ng/ml. Basal serum Lutenising Hormone (LH, follicle stimulating Hormone (FSH was low. Oral glucose tolerance test (OGTT, liver and renal function tests, basal cortisol and thyroid profile, Calcium, phosphorus and Intact Parathyroid hormone (iPTH were normal.Computed tomographyscan of brain showed large pituitary macroadenoma. Automated perimetry confirmed bitemporal hemianopia. A diagnosis of gigantism due to GH secreting pituitary macroadenoma with hypogonadotrophichypogonadism was made. Debulking pituitary surgery followed by somatostatin analogue therapy with gonadal steroid replacement had been planned, but the patient refused further treatment.

  1. Pituitary gigantism: a case report.

    Science.gov (United States)

    Bhattacharjee, Rana; Roy, Ajitesh; Goswami, Soumik; Selvan, Chitra; Chakraborty, Partha P; Ghosh, Sujoy; Biswas, Dibakar; Dasgupta, Ranen; Mukhopadhyay, Satinath; Chowdhury, Subhankar

    2012-12-01

    To present a rare case of gigantism. A 25-year-old lady presented with increased statural growth and enlarged body parts noticed since the age of 14 years, primary amenorrhea, and frontal headache for the last 2 years. She has also been suffering from non-inflammatory low back pain with progressive kyphosis and pain in the knees, ankles, and elbows for the last 5 years. There was no history of visual disturbance, vomiting, galactorrhoea, cold intolerance. She had no siblings. Family history was non-contributory. Blood pressure was normal. Height 221 cm, weight 138 kg, body mass index (BMI)28. There was coarsening of facial features along with frontal bossing and prognathism, large hands and feet, and small goitre. Patient had severe kyphosis and osteoarthritis of knees. Confrontation perimetry suggested bitemporal hemianopia. Breast and pubic hair were of Tanner stage 1. Serum insulin like growth factor-1 (IGF1) was 703 ng/ml with all glucose suppressedgrowth hormone (GH)values of >40 ng/ml. Prolactin was 174 ng/ml. Basal serum Lutenising Hormone (LH), follicle stimulating Hormone (FSH) was low. Oral glucose tolerance test (OGTT), liver and renal function tests, basal cortisol and thyroid profile, Calcium, phosphorus and Intact Parathyroid hormone (iPTH) were normal. Computed tomographyscan of brain showed large pituitary macroadenoma. Automated perimetry confirmed bitemporal hemianopia. A diagnosis of gigantism due to GH secreting pituitary macroadenoma with hypogonadotrophichypogonadism was made. Debulking pituitary surgery followed by somatostatin analogue therapy with gonadal steroid replacement had been planned, but the patient refused further treatment.

  2. Differential diagnosis of gigantic pulmonary abscesses

    International Nuclear Information System (INIS)

    Vinner, M.G.; Khachatryan, M.A.; Abelyan, A.M.

    1985-01-01

    The paper is concerned with an analysis of the clinical X-ray picture in 100 patients with gigantic pulmonary abscesses (the diameter over 6 cm) and in 102 patients with retrostenotic abscesses in central lung cancer, gigantic peripheral cancer with disintegration, tuberculous infiltrate with dissociation, an echinococcal cyst with suppuration and rupture in the bronchus. The reliable clinical differential diagnostic symptoms were not revealed. The chief method of X-ray examination is tomography. In addition to examination of the gigantic focus of lesion in the lung, tomography of the major bronchi should be also performed. The difference between a gigantic pulmonary abscess and peripheral lung cancer is in the nature of the walls and contours; of particular importance is the symptom of nodularity and radiance of the outlines of the pathological shadow which is more distinctive in peripheral cancer. Correct diagnosis was established in 96.6% of the patients

  3. Mammary gigantism and D-penicillamine.

    Science.gov (United States)

    Finer, N; Emery, P; Hicks, B H

    1984-09-01

    Mammary gigantism is a rare complication of D-penicillamine treatment. We report a further case with pathological and endocrine details together with a review of the seven cases previously reported and possible mechanisms.

  4. Hidrocele gigante en paciente anciano

    Directory of Open Access Journals (Sweden)

    Ada Arleny Pérez Mayo

    2014-09-01

    Full Text Available Se presenta el caso de un paciente de 87 años, intervenido por primera vez en el Hospital Nacional “San Pedro Necta” del Departamento de Huehuetenango en Guatemala, por presentar hidrocele gigante de más de veinte años de evolución. El examen físico mostró tumoración translúcida dolorosa en la bolsa escrotal izquierda, con el posible diagnóstico de hidrocele tabicado o no comunicante. El preoperatorio consistió en la canalización de vena periférica, administración de profilaxis antibiótica con ceftriaxona y rasurado de la piel. Durante el acto operatorio se constató hidrocele izquierdo, con acumulación de líquido acuoso de la túnica vaginal que rodeaba el testículo, cuantificable alrededor de los 500 ml. La técnica quirúrgica consistió en la eversión o plicatura de la vaginal. No se presentaron entidades asociadas, como quiste del cordón, hernia inguinal o fimosis. No existieron complicaciones. Se reportó una estadía hospitalaria de cuatro días y el paciente evolucionó favorablemente. No ocurrió recidiva durante el año de seguimiento

  5. Dwarfism and gigantism in historical picture postcards.

    Science.gov (United States)

    Enderle, A

    1998-01-01

    A collection of 893 historical picture postcards from 1900 to 1935, depicting dwarfs and giants, was analysed from medical and psychosocial viewpoints. In conditions such as 'bird headed dwarfism', achondroplasia, cretinism, so-called Aztecs or pinheads, Grebe chondrodysplasia, and acromegalic gigantism, the disorder could be diagnosed easily. In hypopituitary dwarfism, exact diagnosis was more difficult because of heterogeneity. The most common conditions depicted were pituitary dwarfism and achondroplasia. Most of those with gigantism had pituitary gigantism and acromegaly. Brothers and sisters or parents and their children provided evidence of mendelian inheritance of some of these disorders. The cards suggest that being put on show provided, at least in some cases, social benefits. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 PMID:9764085

  6. CT diagnosis of retroperitoneal gigantic liposarcoma

    International Nuclear Information System (INIS)

    Fang Wei; Zheng Zhaohua; Liao Zuyuan; Hu Yinsong

    2009-01-01

    Objective: To analyze CT manifestation of retroperitoneal gigantic liposaxcoma and to improve the image understanding. Methods: Five cases of retroperitoneal gigantic liposarcoma confirmed by surgery and pathology in our hospital were collected. Plain and enhanced CT scan were performed. Results: Of five cases, one was substantive, two was pseudocyst and two was mixed tumor. Several patterns of enhancement such as strip, floccule, irregular patchy or nodular enhancement were revealed inside the lesions on enhanced CT scan. And strip-form of high density enhancement was a typical type. Conclusion: CT examination could determine the tumor's location, size and density, together with the relationship to adjacent organizations CT scan is an important method in diagnosing retroperitoneal gigantic liposarcoma. (authors)

  7. Microplastics in commercial bivalves from China

    International Nuclear Information System (INIS)

    Li, Jiana; Yang, Dongqi; Li, Lan; Jabeen, Khalida; Shi, Huahong

    2015-01-01

    We investigated microplastic pollution in 9 commercial bivalves from a fishery market in China. Multiple types of microplastics, including fibers, fragments and pellets, occurred in the tissue of all bivalves. The number of total microplastics varied from 2.1 to 10.5 items/g and from 4.3 to 57.2 items/individual for bivalves. Scapharca subcrenata contained on average 10.5 items/g and exhibited the highest levels of microplastics by weight. Fibers were the most common microplastics and consisted of more than half of the total microplastics in each of the 8 species. In Alectryonella plicatula, pellets accounted for 60% of the total microplastics. The most common size class was less than 250 μm and accounted for 33–84% of the total microplastics calculated by species. Our results suggest that microplastic pollution was widespread and exhibited a relatively high level in commercial bivalves from China. More intensive investigations on microplastics should be conducted in seafood. - Highlights: • Fiber, fragment and pellet microplastics were found in 9 bivalves. • The abundance of microplastics was 2.1–10.5 items/g. • Fibers were the most common microplastics. • The most common size class of microplastics was less than 250 μm. • Microplastic pollution was widespread and serious in commercial bivalves. - Fiber, fragment and pellet microplastics in the range of 2.1–10.5 items/g were observed in 9 species of commercially popular bivalves from China.

  8. Neurofibromatosis with unilateral lower limb gigantism.

    Science.gov (United States)

    Sabbioni, Giacomo; Rani, Nicola; Devescovi, Valentina

    2010-05-01

    The case of a 3-year-old child diagnosed with Type 1 neurofibromatosis is presented, showing pigmented birthmarks and gigantism of the left lower limb associated with the presence of multiple neurofibromas. Increased bone growth appears to be the direct or indirect consequence of a still undefined paracrine effect of nerve tumor cells.

  9. Microplastics in commercial bivalves from China.

    Science.gov (United States)

    Li, Jiana; Yang, Dongqi; Li, Lan; Jabeen, Khalida; Shi, Huahong

    2015-12-01

    We investigated microplastic pollution in 9 commercial bivalves from a fishery market in China. Multiple types of microplastics, including fibers, fragments and pellets, occurred in the tissue of all bivalves. The number of total microplastics varied from 2.1 to 10.5 items/g and from 4.3 to 57.2 items/individual for bivalves. Scapharca subcrenata contained on average 10.5 items/g and exhibited the highest levels of microplastics by weight. Fibers were the most common microplastics and consisted of more than half of the total microplastics in each of the 8 species. In Alectryonella plicatula, pellets accounted for 60% of the total microplastics. The most common size class was less than 250 μm and accounted for 33-84% of the total microplastics calculated by species. Our results suggest that microplastic pollution was widespread and exhibited a relatively high level in commercial bivalves from China. More intensive investigations on microplastics should be conducted in seafood. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Travel report Mauritania bivalve Molluscs october 2008

    NARCIS (Netherlands)

    Poelman, M.

    2008-01-01

    During the last four years Mauritania has been working on the completion of a Food Safety Program of Bivalve Mollusks, in order to obtain an export approval by the Europe Union. During the preparations for an inspection by the FVO (Food and Veterinary Office) no fisheries or production activities

  11. Bivalves: From individual to population modelling

    NARCIS (Netherlands)

    Saraiva, S.; van der Meer, J.; Kooijman, S.A.L.M.

    2014-01-01

    An individual based population model for bivalves was designed, built and tested in a 0D approach, to simulate the population dynamics of a mussel bed located in an intertidal area. The processes at the individual level were simulated following the dynamic energy budget theory, whereas initial egg

  12. Familial occurrence of cerebral gigantism, Sotos' syndrome.

    Science.gov (United States)

    Hansen, F J; Friis, B

    1976-05-01

    Since the original description of cerebral gigantism, about 85 cases have been reported. Four papers comment on familial occurrence but never in parents and their children. This paper describes the syndrome in a mother and her child, which, together with facts pointing towards prenatal etiology, such as excessive birthweight, striking mutual resemblance and abnormal dermatoglyphics, points to a genetic defect. Previous endocrine studies are enlarged by the findings of normal serum somatomedin and serum prolactin.

  13. Evolution of gigantism in amphiumid salamanders.

    Directory of Open Access Journals (Sweden)

    Ronald M Bonett

    2009-05-01

    Full Text Available The Amphiumidae contains three species of elongate, permanently aquatic salamanders with four diminutive limbs that append one, two, or three toes. Two of the species, Amphiuma means and A. tridactylum, are among the largest salamanders in the world, reaching lengths of more than one meter, whereas the third species (A. pholeter, extinct amphiumids, and closely related salamander families are relatively small. Amphiuma means and A. tridactylum are widespread species and live in a wide range of lowland aquatic habitats on the Coastal Plain of the southeastern United States, whereas A. pholeter is restricted to very specialized organic muck habitats and is syntopic with A. means. Here we present analyses of sequences of mitochondrial and nuclear loci from across the distribution of the three taxa to assess lineage diversity, relationships, and relative timing of divergence in amphiumid salamanders. In addition we analyze the evolution of gigantism in the clade. Our analyses indicate three lineages that have diverged since the late Miocene, that correspond to the three currently recognized species, but the two gigantic species are not each other's closest relatives. Given that the most closely related salamander families and fossil amphiumids from the Upper Cretaceous and Paleocene are relatively small, our results suggest at least two extreme changes in body size within the Amphuimidae. Gigantic body size either evolved once as the ancestral condition of modern amphiumas, with a subsequent strong size reduction in A. pholeter, or gigantism independently evolved twice in the modern species, A. means and A. tridactylum. These patterns are concordant with differences in habitat breadth and range size among lineages, and have implications for reproductive isolation and diversification of amphiumid salamanders.

  14. Dwarfism and gigantism in historical picture postcards.

    OpenAIRE

    Enderle, A

    1998-01-01

    A collection of 893 historical picture postcards from 1900 to 1935, depicting dwarfs and giants, was analysed from medical and psychosocial viewpoints. In conditions such as 'bird headed dwarfism', achondroplasia, cretinism, so-called Aztecs or pinheads, Grebe chondrodysplasia, and acromegalic gigantism, the disorder could be diagnosed easily. In hypopituitary dwarfism, exact diagnosis was more difficult because of heterogeneity. The most common conditions depicted were pituitary dwarfism and...

  15. Gigantic Suprapubic Lymphedema: A Case Study

    Directory of Open Access Journals (Sweden)

    Roozbeh Tanhaeivash

    2016-08-01

    Full Text Available We present the first case study of idiopathic gigantic suprapubic lymphedema and buried penis treated with puboscrotal reconstruction in a patient with initial extreme obesity after an extensive weight reduction (120 kg. Massive localized lymphedema of the suprapubic region should be differentiated from the scrotal type. Severe lymphedema could not resolve on its own and weight reduction does not seem to be helpful in such cases.

  16. Giant basal cell carcinoma Carcinoma basocelular gigante

    Directory of Open Access Journals (Sweden)

    Nilton Nasser

    2012-06-01

    Full Text Available The basal cell carcinoma is the most common skin cancer but the giant vegetating basal cell carcinoma reaches less than 0.5 % of all basal cell carcinoma types. The Giant BCC, defined as a lesion with more than 5 cm at its largest diameter, is a rare form of BCC and commonly occurs on the trunk. This patient, male, 42 years old presents a Giant Basal Cell Carcinoma which reaches 180 cm2 on the right shoulder and was negligent in looking for treatment. Surgical treatment was performed and no signs of dissemination or local recurrence have been detected after follow up of five years.O carcinoma basocelular é o tipo mais comum de câncer de pele, mas o carcinoma basocelular gigante vegetante não atinge 0,5% de todos os tipos de carcinomas basocelulares. O Carcinoma Basocelular Gigante, definido como lesão maior que 5 cm no maior diâmetro, é uma forma rara de carcinoma basocelular e comumente ocorre no tronco. Este paciente apresenta um Carcinoma Basocelular Gigante com 180cm² no ombro direito e foi negligente em procurar tratamento. Foi realizado tratamento cirúrgico e nenhum sinal de disseminação ou recorrência local foi detectada após 5 anos.

  17. Bivalve grazing can shape phytoplankton communities

    Science.gov (United States)

    Lucas, Lisa; Cloern, James E.; Thompson, Janet K.; Stacey, Mark T.; Koseff, Jeffrey K.

    2016-01-01

    The ability of bivalve filter feeders to limit phytoplankton biomass in shallow waters is well-documented, but the role of bivalves in shaping phytoplankton communities is not. The coupled effect of bivalve grazing at the sediment-water interface and sinking of phytoplankton cells to that bottom filtration zone could influence the relative biomass of sinking (diatoms) and non-sinking phytoplankton. Simulations with a pseudo-2D numerical model showed that benthic filter feeding can interact with sinking to alter diatom:non-diatom ratios. Cases with the smallest proportion of diatom biomass were those with the fastest sinking speeds and strongest bivalve grazing rates. Hydrodynamics modulated the coupled sinking-grazing influence on phytoplankton communities. For example, in simulations with persistent stratification, the non-sinking forms accumulated in the surface layer away from bottom grazers while the sinking forms dropped out of the surface layer toward bottom grazers. Tidal-scale stratification also influenced vertical gradients of the two groups in opposite ways. The model was applied to Suisun Bay, a low-salinity habitat of the San Francisco Bay system that was transformed by the introduction of the exotic clam Potamocorbula amurensis. Simulation results for this Bay were similar to (but more muted than) those for generic habitats, indicating that P. amurensis grazing could have caused a disproportionate loss of diatoms after its introduction. Our model simulations suggest bivalve grazing affects both phytoplankton biomass and community composition in shallow waters. We view these results as hypotheses to be tested with experiments and more complex modeling approaches.

  18. Gigantism of the foot: our experience in seven cases.

    Science.gov (United States)

    Turra, S; Santini, S; Cagnoni, G; Jacopetti, T

    1998-01-01

    We report our experience in seven patients with congenital gigantism of the foot with the following diagnoses: neurofibromatosis (two), fibrolipomatosis (two), Proteus syndrome (two), and idiopathic localized gigantism (one). Our purpose is to introduce a new classification of foot gigantism, based on the concept of "neuroinduction." In our experience, intraoperative examination and subsequent histologic examination show consistently pathologic findings in the plantar nerve and its terminal branches in the foot affected by gigantism. Limited surgical treatment was used in five patients. To prevent forefoot enlargement and recurrence of deformity, we suggest complete ray resection. We evaluated our results using radiographs, functional status, and cosmetic considerations.

  19. Operation of arc heating furnace on manufacturing gigantic ingots and segregation of gigantic ingots

    International Nuclear Information System (INIS)

    Niimi, Takayasu; Okamura, Masayoshi

    1976-01-01

    The techniques and procedure for manufacturing gigantic ingots heavier than 200 t are described. Especially, practical results of an arc heating furnace which plays an important role in the procedure and segregation of gigantic ingots are discussed in detail. By appropriate operations of the arc heating furnance, hydrogen and phosphorus are kept unchanged, and oxygen and sulphur decrease to very low levels. Furthermore, the temperature can be accurately controlled. The application of multipour technique reduces segregation and its degree is dependent on kinds of steel. V-segregation and inverted V-segregation in steel deoxidized with carbon in vacuum seem to be very slight. (auth.)

  20. Gigantism and Its Implications for the History of Life.

    Science.gov (United States)

    Vermeij, Geerat J

    2016-01-01

    Gigantism-very large body size-is an ecologically important trait associated with competitive superiority. Although it has been studied in particular cases, the general conditions for the evolution and maintenance of gigantism remain obscure. I compiled sizes and dates for the largest species in 3 terrestrial and 7 marine trophic and habitat categories of animals from throughout the Phanerozoic. The largest species (global giants) in all categories are of post-Paleozoic age. Gigantism at this level appeared tens to hundreds of millions of years after mass extinctions and long after the origins of clades in which it evolved. Marine gigantism correlates with high planktic or seafloor productivity, but on land the correspondence between productivity and gigantism is weak at best. All global giants are aerobically active animals, not gentle giants with low metabolic demands. Oxygen concentration in the atmosphere correlates with gigantism in the Paleozoic but not thereafter, likely because of the elaboration of efficient gas-exchange systems in clades containing giants. Although temperature and habitat size are important in the evolution of very large size in some cases, the most important (and rare) enabling circumstance is a highly developed ecological infrastructure in which essential resources are abundant and effectively recycled and reused, permitting activity levels to increase and setting the stage for gigantic animals to evolve. Gigantism as a hallmark of competitive superiority appears to have lost its luster on land after the Mesozoic in favor of alternative means of achieving dominance, especially including social organization and coordinated food-gathering.

  1. Fungal cell gigantism during mammalian infection.

    Directory of Open Access Journals (Sweden)

    Oscar Zaragoza

    2010-06-01

    Full Text Available The interaction between fungal pathogens with the host frequently results in morphological changes, such as hyphae formation. The encapsulated pathogenic fungus Cryptococcus neoformans is not considered a dimorphic fungus, and is predominantly found in host tissues as round yeast cells. However, there is a specific morphological change associated with cryptococcal infection that involves an increase in capsule volume. We now report another morphological change whereby gigantic cells are formed in tissue. The paper reports the phenotypic characterization of giant cells isolated from infected mice and the cellular changes associated with giant cell formation. C. neoformans infection in mice resulted in the appearance of giant cells with cell bodies up to 30 microm in diameter and capsules resistant to stripping with gamma-radiation and organic solvents. The proportion of giant cells ranged from 10 to 80% of the total lung fungal burden, depending on infection time, individual mice, and correlated with the type of immune response. When placed on agar, giant cells budded to produce small daughter cells that traversed the capsule of the mother cell at the speed of 20-50 m/h. Giant cells with dimensions that approximated those in vivo were observed in vitro after prolonged culture in minimal media, and were the oldest in the culture, suggesting that giant cell formation is an aging-dependent phenomenon. Giant cells recovered from mice displayed polyploidy, suggesting a mechanism by which gigantism results from cell cycle progression without cell fission. Giant cell formation was dependent on cAMP, but not on Ras1. Real-time imaging showed that giant cells were engaged, but not engulfed by phagocytic cells. We describe a remarkable new strategy for C. neoformans to evade the immune response by enlarging cell size, and suggest that gigantism results from replication without fission, a phenomenon that may also occur with other fungal pathogens.

  2. Fungal cell gigantism during mammalian infection.

    Science.gov (United States)

    Zaragoza, Oscar; García-Rodas, Rocío; Nosanchuk, Joshua D; Cuenca-Estrella, Manuel; Rodríguez-Tudela, Juan Luis; Casadevall, Arturo

    2010-06-17

    The interaction between fungal pathogens with the host frequently results in morphological changes, such as hyphae formation. The encapsulated pathogenic fungus Cryptococcus neoformans is not considered a dimorphic fungus, and is predominantly found in host tissues as round yeast cells. However, there is a specific morphological change associated with cryptococcal infection that involves an increase in capsule volume. We now report another morphological change whereby gigantic cells are formed in tissue. The paper reports the phenotypic characterization of giant cells isolated from infected mice and the cellular changes associated with giant cell formation. C. neoformans infection in mice resulted in the appearance of giant cells with cell bodies up to 30 microm in diameter and capsules resistant to stripping with gamma-radiation and organic solvents. The proportion of giant cells ranged from 10 to 80% of the total lung fungal burden, depending on infection time, individual mice, and correlated with the type of immune response. When placed on agar, giant cells budded to produce small daughter cells that traversed the capsule of the mother cell at the speed of 20-50 m/h. Giant cells with dimensions that approximated those in vivo were observed in vitro after prolonged culture in minimal media, and were the oldest in the culture, suggesting that giant cell formation is an aging-dependent phenomenon. Giant cells recovered from mice displayed polyploidy, suggesting a mechanism by which gigantism results from cell cycle progression without cell fission. Giant cell formation was dependent on cAMP, but not on Ras1. Real-time imaging showed that giant cells were engaged, but not engulfed by phagocytic cells. We describe a remarkable new strategy for C. neoformans to evade the immune response by enlarging cell size, and suggest that gigantism results from replication without fission, a phenomenon that may also occur with other fungal pathogens.

  3. Sotos syndrome: An interesting disorder with gigantism

    Science.gov (United States)

    Nalini, A.; Biswas, Arundhati

    2008-01-01

    We report the case of a 16-year-old boy diagnosed to have Sotos syndrome, with rare association of bilateral primary optic atrophy and epilepsy. He presented with accelerated linear growth, facial gestalt, distinctive facial features, seizures and progressive diminution of vision in both eyes. He had features of gigantism from early childhood. An MRI showed that brain and endocrine functions were normal. This case is of interest, as we have to be aware of this not so rare disorder. In addition to the classic features, there were two unusual associations with Sotos syndrome in the patient. PMID:19893668

  4. Sotos syndrome: An interesting disorder with gigantism.

    Science.gov (United States)

    Nalini, A; Biswas, Arundhati

    2008-07-01

    We report the case of a 16-year-old boy diagnosed to have Sotos syndrome, with rare association of bilateral primary optic atrophy and epilepsy. He presented with accelerated linear growth, facial gestalt, distinctive facial features, seizures and progressive diminution of vision in both eyes. He had features of gigantism from early childhood. An MRI showed that brain and endocrine functions were normal. This case is of interest, as we have to be aware of this not so rare disorder. In addition to the classic features, there were two unusual associations with Sotos syndrome in the patient.

  5. Sotos syndrome: An interesting disorder with gigantism

    Directory of Open Access Journals (Sweden)

    Nalini A

    2008-01-01

    Full Text Available We report the case of a 16-year-old boy diagnosed to have Sotos syndrome, with rare association of bilateral primary optic atrophy and epilepsy. He presented with accelerated linear growth, facial gestalt, distinctive facial features, seizures and progressive diminution of vision in both eyes. He had features of gigantism from early childhood. An MRI showed that brain and endocrine functions were normal. This case is of interest, as we have to be aware of this not so rare disorder. In addition to the classic features, there were two unusual associations with Sotos syndrome in the patient.

  6. Central neurocytoma presenting with gigantism: case report.

    Science.gov (United States)

    Araki, Y; Sakai, N; Andoh, T; Yoshimura, S; Yamada, H

    1992-08-01

    We report a case of central neurocytoma presenting with gigantism. The patient was a 19-year-old man with a 2-year history of rapid growth. Computed tomography revealed a round, slightly enhancing calcified tumor in the septal region. This lesion was resected, and postoperative radiotherapy was given. The preoperative serum growth hormone level was 20.7 ng/mL, and postoperatively this fell to 0.9 ng/mL. Pituitary dysfunction was not noted either before or after the operation. A low level of production of growth hormone releasing factor was detected when tumor cells obtained during surgery were cultured.

  7. Gigantic subcutaneous lipoma – A case report

    Directory of Open Access Journals (Sweden)

    Christian Lyngsaa Lang

    2015-03-01

    Full Text Available Lipomas are the most common benign mesenchymal tumour. The solitary subcutaneous lipoma accounts for approximately one-quarter to one-half of all soft tissue tumours. The preferred locations include the trunk, shoulder, upper arm, and the neck. In this case report, we present a gigantic axillary lipoma weighing 23.35 kg. Due to the tumour mass and its long-term presence, the lipoma caused anatomical changes in the axilla making its removal challenging and difficult.

  8. Ecological drivers and habitat associations of estuarine bivalves

    OpenAIRE

    McKeon, C. Seabird; Tunberg, Bj?rn G.; Johnston, Cora A.; Barshis, Daniel J.

    2015-01-01

    Community composition of the infaunal bivalve fauna of the St. Lucie Estuary and southern Indian River Lagoon, eastern Florida was sampled quarterly for 10 years as part of a long-term benthic monitoring program. A total of 38,514 bivalves of 137 taxa were collected and identified. We utilized this data, along with sediment samples and environmental measurements gathered concurrently, to assess the community composition, distribution, and ecological drivers of the infaunal bivalves of this es...

  9. Ondas T negativas gigantes de origen indeterminado

    Directory of Open Access Journals (Sweden)

    Eduardo Eyheremendy

    2009-01-01

    Full Text Available Se define onda T negativa gigante o inversión masiva de la onda T a la aparición de ondas T negativas con una amplitud = 1 mV en por lo menos dos derivaciones contiguas del ECG. Se presenta el caso de una paciente de 66 años con antecedentes de dislipidemia tipo IV e hipertensión arterial leve, a la que en buen estado de salud y totalmente asintomática en un examen de rutina se le detecta en el ECG de superficie un hemibloqueo anterior y ondas T negativas gigantes en las derivaciones I, II, aVL, aVF y de V1 a V6. La paciente fue internada en la UCI, donde se descartó que fueran de origen coronario. Durante el seguimiento, las ondas T se tornaron menos negativas hasta que al cabo de un tiempo (45 días aproximadamente se normalizaron. A pesar de los estudios cardiológicos y no cardiológicos realizados, no se pudo establecer su origen.REV ARGENT CARDIOL 2009;77:131-134.

  10. Hereditary pituitary hyperplasia with infantile gigantism.

    Science.gov (United States)

    Gläsker, Sven; Vortmeyer, Alexander O; Lafferty, Antony R A; Hofman, Paul L; Li, Jie; Weil, Robert J; Zhuang, Zhengping; Oldfield, Edward H

    2011-12-01

    We report hereditary pituitary hyperplasia. The objective of the study was to describe the results of the clinical and laboratory analysis of this rare instance of hereditary pituitary hyperplasia. The study is a retrospective analysis of three cases from one family. The study was conducted at the National Institutes of Health, a tertiary referral center. A mother and both her sons had very early-onset gigantism associated with high levels of serum GH and prolactin. The condition was treated by total hypophysectomy. We performed clinical, pathological, and molecular evaluations, including evaluation basal and provocative endocrine testing, neuroradiological assessment, and assessment of the pituitary tissue by microscopic evaluation, immunohistochemistry, and electron microscopy. All three family members had very early onset of gigantism associated with abnormally high serum levels of GH and prolactin. Serum GHRH levels were not elevated in either of the boys. The clinical, radiographic, surgical, and histological findings indicated mammosomatotroph hyperplasia. The pituitary gland of both boys revealed diffuse mammosomatotroph hyperplasia of the entire pituitary gland without evidence of adenoma. Prolactin and GH were secreted by the same cells within the same secretory granules. Western blot and immunohistochemistry demonstrated expression of GHRH in clusters of cells distributed throughout the hyperplastic pituitary of both boys. This hereditary condition seems to be a result of embryonic pituitary maldevelopment with retention and expansion of the mammosomatotrophs. The findings suggest that it is caused by paracrine or autocrine pituitary GHRH secretion during pituitary development.

  11. Sex Determination and Polyploid Gigantism in the Dwarf Surfclam (Mulinia Lateralis Say)

    Science.gov (United States)

    Guo, X.; Allen-Jr., S. K.

    1994-01-01

    Mulinia lateralis, the dwarf surfclam, is a suitable model for bivalve genetics because it is hardy and has a short generation time. In this study, gynogenetic and triploid. M. lateralis were successfully induced. For gynogenesis, eggs were fertilized with sperm irradiated with ultraviolet light and subsequently treated with cytochalasin B to block the release of the second polar body (PB2). Triploidy was induced by blocking PB2 in normally fertilized eggs. The survival of gynogenetic diploids was very low, only 0.7% to 8 days post-fertilization (PF), compared with 15.2% in the triploid groups and 27.5% in the normal diploid control. Larvae in all groups metamorphosed at 8-10 days PF, and there was no significant post-larval mortality. At sexual maturation (2-3 months PF), all gynogenetic diploids were female, and there was no significant difference (P > 0.05) in sex ratio between diploids and triploids. These results suggested that the dwarf surfclam may have an XX-female, XY-male sex determination with Y-domination. Compared with diploids, triploids had a relative fecundity of 59% for females and 80% for males. Eggs produced by triploid females were 53% larger (P 0.33) different from normal diploid females, suggesting that inbreeding depression was minimal in meiosis II gynogens. Triploid clams were significantly larger (P gigantism due to the increased cell volume and a lack of cell-number compensation. PMID:7896101

  12. Unilateral glaucoma in Sotos syndrome (cerebral gigantism).

    Science.gov (United States)

    Yen, M T; Gedde, S J; Flynn, J T

    2000-12-01

    To report a patient with unilateral glaucoma associated with Sotos syndrome. Sotos syndrome (cerebral gigantism) is a disorder of growth and development with characteristic facial changes and normal endocrine function. Ocular manifestations may also include megalocornea, iris hypoplasia, cataracts, megalophthalmos, strabismus, nystagmus, and retinal dystrophy. Case report. A 50 year-old man with the clinical features of Sotos syndrome presented with complaints of decreased vision in the left eye. Ophthalmologic examination revealed bilateral megalocornea, megalophthalmos, iris hypoplasia and transillumination defects, cataracts, and unilateral glaucoma. Intraocular pressure was lowered, and visual field loss was stabilized with topical medications. Sotos syndrome patients should be examined routinely to allow for early detection and treatment of potential ocular problems, including glaucoma.

  13. Gigantism and Its Implications for the History of Life.

    Directory of Open Access Journals (Sweden)

    Geerat J Vermeij

    Full Text Available Gigantism-very large body size-is an ecologically important trait associated with competitive superiority. Although it has been studied in particular cases, the general conditions for the evolution and maintenance of gigantism remain obscure. I compiled sizes and dates for the largest species in 3 terrestrial and 7 marine trophic and habitat categories of animals from throughout the Phanerozoic. The largest species (global giants in all categories are of post-Paleozoic age. Gigantism at this level appeared tens to hundreds of millions of years after mass extinctions and long after the origins of clades in which it evolved. Marine gigantism correlates with high planktic or seafloor productivity, but on land the correspondence between productivity and gigantism is weak at best. All global giants are aerobically active animals, not gentle giants with low metabolic demands. Oxygen concentration in the atmosphere correlates with gigantism in the Paleozoic but not thereafter, likely because of the elaboration of efficient gas-exchange systems in clades containing giants. Although temperature and habitat size are important in the evolution of very large size in some cases, the most important (and rare enabling circumstance is a highly developed ecological infrastructure in which essential resources are abundant and effectively recycled and reused, permitting activity levels to increase and setting the stage for gigantic animals to evolve. Gigantism as a hallmark of competitive superiority appears to have lost its luster on land after the Mesozoic in favor of alternative means of achieving dominance, especially including social organization and coordinated food-gathering.

  14. Etiologies and clinical presentation of gigantism in Algeria.

    Science.gov (United States)

    Chentli, Farida; Azzoug, Said; Amani, Mohammed El Amine; Haddam, Ali El Mahdi; Chaouki, Dalal; Meskine, Djamila; Chaouki, Mohamed Lamine

    2012-01-01

    True gigantism is an exceptional and fascinating pediatric disease. Our aim in this study was to describe the different etiologies of a large group of children with gigantism and the natural history of their growth. In this multicenter study, we considered as giant children, adolescents and adults whose heights were ≥3 SD compared to their target stature or to our population average lengths. Isolated hypogonadism and Klinefelter syndrome were excluded from this series. All underwent clinical exam, and hormonal and neurological investigations. From 1980 to 2010, we observed 30 giants: 26 males (86.6%) and 4 females (mean age 19.8 ± 11 years). Among the 13 patients (40.3%) who consulted before the age of 16 years, 9 had acromegaly and 6 had mental retardation and body malformations. Based on growth hormone (GH) secretion evaluation, 2 groups were observed: pituitary gigantism (n = 16): GH = 150 ± 252 ng/ml (n ≤ 5), and other causes with normal GH (0.7 ± 0.6 ng/ml): 6 Sotos syndrome and 8 idiopathic cases. Only the first group had neurological, ophthalmological, metabolic and cardiovascular complications and received treatment. The result was not optimal as GH normalization was not observed. Reduction of tumor size and decreased GH plasma values were not observed. Gigantism predominates in males. The main cause is GH excess. The diagnosis was very late except for cerebral gigantism. Complications were observed in pituitary gigantism only. Copyright © 2012 S. Karger AG, Basel.

  15. Persistent organic pollutants in four bivalve species from Svalbard waters

    International Nuclear Information System (INIS)

    Vieweg, Ireen; Hop, Haakon; Brey, Thomas; Huber, Sandra; Ambrose, William G.; Locke V, William L.; Gabrielsen, Geir W.

    2012-01-01

    Organochlorine compounds (OC) were determined in Arctic bivalves (Mya truncata, Serripes groenlandicus, Hiatella arctica and Chlamys islandica) from Svalbard with regard to differences in geographic location, species and variations related to their size and age. Higher chlorinated polychlorinated biphenyls (PCB 101–PCB 194), chlordanes and α-hexachlorocyclohexane (α-HCH) were consistently detected in the bivalves and PCBs dominated the OC load in the organisms. OC concentrations were highest in Mya truncata and the lowest in Serripes groenlandicus. Species-specific OC levels were likely related to differences in the species’ food source, as indicated by the δ 13 C results, rather than size and age. Higher OC concentrations were observed in bivalves from Kongsfjorden compared to the northern sampling locations Liefdefjorden and Sjuøyane. The spatial differences might be related to different water masses influencing Kongsfjorden (Atlantic) and the northern locations (Arctic), with differing phytoplankton bloom situations. - Highlights: ► Organochlorine compounds (OC) were analyzed in 4 bivalve species from Svalbard. ► Polychlorinated biphenyls dominated the OC load observed in the bivalves. ► Atlantic water influenced bivalves had higher OC levels than those from Arctic water. ► Location and species, rather than size and age, determined the OC pattern found. - New findings of organochlorines in Arctic bivalves that are central for evaluating the importance of geographical location and species for the organochlorine pattern in benthic organisms.

  16. Artificially evolved functional shell morphology of burrowing bivalves

    DEFF Research Database (Denmark)

    Germann, D. P.; Schatz, W.; Hotz, Peter Eggenberger

    2014-01-01

    The morphological evolution of bivalves is documented by a rich fossil record. It is believed that the shell shape and surface sculpture play an important role for the burrowing performance of endobenthic species. While detailed morphometric studies of bivalve shells have been done...... dimensional (3D) objects, the first ever artificial evolution of a physical bivalve shell was performed. The result was a vertically flattened shell occupying only the top sediment layers. Insufficient control of the sediment was the major limitation of the setup and restricted the significance of the results...

  17. Gigantism and Its Implications for the History of Life

    Science.gov (United States)

    Vermeij, Geerat J.

    2016-01-01

    Gigantism—very large body size—is an ecologically important trait associated with competitive superiority. Although it has been studied in particular cases, the general conditions for the evolution and maintenance of gigantism remain obscure. I compiled sizes and dates for the largest species in 3 terrestrial and 7 marine trophic and habitat categories of animals from throughout the Phanerozoic. The largest species (global giants) in all categories are of post-Paleozoic age. Gigantism at this level appeared tens to hundreds of millions of years after mass extinctions and long after the origins of clades in which it evolved. Marine gigantism correlates with high planktic or seafloor productivity, but on land the correspondence between productivity and gigantism is weak at best. All global giants are aerobically active animals, not gentle giants with low metabolic demands. Oxygen concentration in the atmosphere correlates with gigantism in the Paleozoic but not thereafter, likely because of the elaboration of efficient gas-exchange systems in clades containing giants. Although temperature and habitat size are important in the evolution of very large size in some cases, the most important (and rare) enabling circumstance is a highly developed ecological infrastructure in which essential resources are abundant and effectively recycled and reused, permitting activity levels to increase and setting the stage for gigantic animals to evolve. Gigantism as a hallmark of competitive superiority appears to have lost its luster on land after the Mesozoic in favor of alternative means of achieving dominance, especially including social organization and coordinated food-gathering. PMID:26771527

  18. Pituitary gigantism: a retrospective case series.

    Science.gov (United States)

    Creo, Ana L; Lteif, Aida N

    2016-05-01

    Pituitary gigantism (PG) is a rare pediatric disease with poorly defined long-term outcomes. Our aim is to describe the longitudinal clinical course in PG patients using a single-center, retrospective cohort study. Patients younger than 19 years diagnosed with PG were identified. Thirteen cases were confirmed based on histopathology of a GH secreting adenoma or hyperplasia and a height >2 SD for age and gender. Laboratory studies, initial pathology, and imaging were abstracted. Average age at diagnosis was 13 years with an average initial tumor size of 7.4×3.8 mm. Initial transsphenoidal surgery was curative in 3/12 patients. Four of the nine patients who failed the initial surgery required a repeat procedure. Octreotide successfully normalized GH levels in 1/6 patients with disease refractory to surgery (1/6). Two out of five patients received pegvisomant after failing octreotide but only one patient responded to treatment. Five patients were ultimately treated with radiosurgery or radiation patients were followed for an average of 10 years. PG is difficult to treat. In most patients, the initial transsphenoidal surgery failed to normalize GH levels. If the initial surgery was unsuccessful, repeat surgery was unlikely to control GH secretion. Treatment with octreotide or pegvisomant was successful in less than half the patients failing surgery. Radiosurgery was curative, but is not an optimal treatment for pediatric patients. Despite the small sample, our study suggests that the treatment outcome of pediatric PG may be different than adults.

  19. Geochemical aspects of Meretrix casta (bivalve) shells of Vellar ...

    African Journals Online (AJOL)

    SAM

    2014-05-14

    May 14, 2014 ... The bivalve mollusk, Meretrix casta shells are abundant in the Vellar estuary along the East .... the Shervarayan hills of Salem District in Tamil Nadu, India. .... coast of Peninsular Malaysia and its potential as biomaterial for use.

  20. Immunotoxicological effects of environmental contaminants on marine bivalves.

    Science.gov (United States)

    Renault, T

    2015-09-01

    Coastal areas are complex environments frequently contaminated by numerous pollutants that represent a potential threat to marine organisms, especially bivalves. These pollutants may have major ecological consequences. Although effects of different environmental contaminants on the immune system in marine bivalves have been already reported, a few of reviews summarizes these effects. The main purpose of this chapter relies on summarizing recent body of data on immunotoxicity in bivalves subjected to contaminants. Immune effects of heavy metals, pesticides, HAP, PCB and pharmaceuticals are presented and discussed and a particular section is devoted to nanoparticle effects. A large body of literature is now available on this topic. Finally, the urgent need of a better understanding of complex interactions between contaminants, marine bivalves and infectious diseases is noticed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Pituitary gigantism: update on molecular biology and management.

    Science.gov (United States)

    Lodish, Maya B; Trivellin, Giampaolo; Stratakis, Constantine A

    2016-02-01

    To provide an update on the mechanisms leading to pituitary gigantism, as well as to familiarize the practitioner with the implication of these genetic findings on treatment decisions. Prior studies have identified gigantism as a feature of a number of monogenic disorders, including mutations in the aryl hydrocarbon receptor interacting protein gene, multiple endocrine neoplasia types 1 and 4, McCune Albright syndrome, Carney complex, and the paraganglioma, pheochromocytoma, and pituitary adenoma association because of succinate dehydrogenase defects. We recently described a previously uncharacterized form of early-onset pediatric gigantism caused by microduplications on chromosome Xq26.3 and we termed it X-LAG (X-linked acrogigantism). The age of onset of increased growth in X-LAG is significantly younger than other pituitary gigantism cases, and control of growth hormone excess is particularly challenging. Knowledge of the molecular defects that underlie pituitary tumorigenesis is crucial for patient care as they guide early intervention, screening for associated conditions, genetic counseling, surgical approach, and choice of medical management. Recently described microduplications of Xq26.3 account for more than 80% of the cases of early-onset pediatric gigantism. Early recognition of X-LAG may improve outcomes, as successful control of growth hormone excess requires extensive anterior pituitary resection and are difficult to manage with medical therapy alone.

  2. Late paleozoic fusulinoidean gigantism driven by atmospheric hyperoxia.

    Science.gov (United States)

    Payne, Jonathan L; Groves, John R; Jost, Adam B; Nguyen, Thienan; Moffitt, Sarah E; Hill, Tessa M; Skotheim, Jan M

    2012-09-01

    Atmospheric hyperoxia, with pO(2) in excess of 30%, has long been hypothesized to account for late Paleozoic (360-250 million years ago) gigantism in numerous higher taxa. However, this hypothesis has not been evaluated statistically because comprehensive size data have not been compiled previously at sufficient temporal resolution to permit quantitative analysis. In this study, we test the hyperoxia-gigantism hypothesis by examining the fossil record of fusulinoidean foraminifers, a dramatic example of protistan gigantism with some individuals exceeding 10 cm in length and exceeding their relatives by six orders of magnitude in biovolume. We assembled and examined comprehensive regional and global, species-level datasets containing 270 and 1823 species, respectively. A statistical model of size evolution forced by atmospheric pO(2) is conclusively favored over alternative models based on random walks or a constant tendency toward size increase. Moreover, the ratios of volume to surface area in the largest fusulinoideans are consistent in magnitude and trend with a mathematical model based on oxygen transport limitation. We further validate the hyperoxia-gigantism model through an examination of modern foraminiferal species living along a measured gradient in oxygen concentration. These findings provide the first quantitative confirmation of a direct connection between Paleozoic gigantism and atmospheric hyperoxia. © 2012 The Author(s). Evolution© 2012 The Society for the Study of Evolution.

  3. Microbial Diseases of Bivalve Mollusks: Infections, Immunology and Antimicrobial Defense.

    Science.gov (United States)

    Zannella, Carla; Mosca, Francesco; Mariani, Francesca; Franci, Gianluigi; Folliero, Veronica; Galdiero, Marilena; Tiscar, Pietro Giorgio; Galdiero, Massimiliano

    2017-06-17

    A variety of bivalve mollusks (phylum Mollusca, class Bivalvia) constitute a prominent commodity in fisheries and aquacultures, but are also crucial in order to preserve our ecosystem's complexity and function. Bivalve mollusks, such as clams, mussels, oysters and scallops, are relevant bred species, and their global farming maintains a high incremental annual growth rate, representing a considerable proportion of the overall fishery activities. Bivalve mollusks are filter feeders; therefore by filtering a great quantity of water, they may bioaccumulate in their tissues a high number of microorganisms that can be considered infectious for humans and higher vertebrates. Moreover, since some pathogens are also able to infect bivalve mollusks, they are a threat for the entire mollusk farming industry. In consideration of the leading role in aquaculture and the growing financial importance of bivalve farming, much interest has been recently devoted to investigate the pathogenesis of infectious diseases of these mollusks in order to be prepared for public health emergencies and to avoid dreadful income losses. Several bacterial and viral pathogens will be described herein. Despite the minor complexity of the organization of the immune system of bivalves, compared to mammalian immune systems, a precise description of the different mechanisms that induce its activation and functioning is still missing. In the present review, a substantial consideration will be devoted in outlining the immune responses of bivalves and their repertoire of immune cells. Finally, we will focus on the description of antimicrobial peptides that have been identified and characterized in bivalve mollusks. Their structural and antimicrobial features are also of great interest for the biotechnology sector as antimicrobial templates to combat the increasing antibiotic-resistance of different pathogenic bacteria that plague the human population all over the world.

  4. Ecological drivers and habitat associations of estuarine bivalves

    Directory of Open Access Journals (Sweden)

    C. Seabird McKeon

    2015-11-01

    Full Text Available Community composition of the infaunal bivalve fauna of the St. Lucie Estuary and southern Indian River Lagoon, eastern Florida was sampled quarterly for 10 years as part of a long-term benthic monitoring program. A total of 38,514 bivalves of 137 taxa were collected and identified. We utilized this data, along with sediment samples and environmental measurements gathered concurrently, to assess the community composition, distribution, and ecological drivers of the infaunal bivalves of this estuary system. Salinity had the strongest influence on bivalve assemblage across the 15 sites, superseding the influences of sediment type, water turbidity, temperature and other environmental parameters. The greatest diversity was found in higher salinity euhaline sites, while the greatest abundance of individual bivalves was found in medium salinity mixohaline sites, the lowest diversity and abundances were found in the low salinity oligohaline sites, demonstrating a strong positive association between salinity and diversity/abundance. Water management decisions for the estuary should incorporate understanding of the role of salinity on bivalve diversity, abundance, and ecosystem function.

  5. Ecological drivers and habitat associations of estuarine bivalves.

    Science.gov (United States)

    McKeon, C Seabird; Tunberg, Björn G; Johnston, Cora A; Barshis, Daniel J

    2015-01-01

    Community composition of the infaunal bivalve fauna of the St. Lucie Estuary and southern Indian River Lagoon, eastern Florida was sampled quarterly for 10 years as part of a long-term benthic monitoring program. A total of 38,514 bivalves of 137 taxa were collected and identified. We utilized this data, along with sediment samples and environmental measurements gathered concurrently, to assess the community composition, distribution, and ecological drivers of the infaunal bivalves of this estuary system. Salinity had the strongest influence on bivalve assemblage across the 15 sites, superseding the influences of sediment type, water turbidity, temperature and other environmental parameters. The greatest diversity was found in higher salinity euhaline sites, while the greatest abundance of individual bivalves was found in medium salinity mixohaline sites, the lowest diversity and abundances were found in the low salinity oligohaline sites, demonstrating a strong positive association between salinity and diversity/abundance. Water management decisions for the estuary should incorporate understanding of the role of salinity on bivalve diversity, abundance, and ecosystem function.

  6. Constitutional chromosome anomalies in patients with cerebral gigantism (Sotos syndrome).

    Science.gov (United States)

    Haeusler, G; Guchev, Z; Köhler, I; Schober, E; Haas, O; Frisch, H

    1993-01-01

    Two boys are presented with the clinical features of cerebral gigantism and chromosomal variants which have not been described so far in this syndrome. In the first boy a de novo pericentric inversion of chromosome Y was found, the karyotypes of all other investigated family members were normal. The patient had an obstructive hypertrophic cardiomyopathy and atrial septal defect type II. The second boy had inherited pericentric inversion of the heterochromatic region of chromosome 9 from his mother. This chromosome 9 variant was also found in his sister who had a similar phenotype but without gigantism. Endocrine evaluation demonstrated normal results in both boys. The intellectual achievement in both cases was average.

  7. [Cerebral gigantism. Review of the literature apropos of one case].

    Science.gov (United States)

    Maes, B; Caron, J; Couchot, J; Gross, A; Leutenegger, M

    The authors report a case of cerebral gigantism and review 83 cases found in the world literature. The diagnosis depends on the association of several factors, none of which alone are specific but which, on the whole, form a fairly characteristic picture. Large size at birth, leading only rarely to gigantism at adult age. Facial dysmorphia of acromegaloid type. Ecephalopathy with mental deficiency without any neuroradiological abnormality. Finally, endocrine investigations and somatotropic function were normal. No etiology has been found up to now. The most satisfactory theory is that of a hypothalamopituitary disturbance. Treatment may simple avoid excess height at adult age and is based on sex hormone therapy to accelerate bony maturation.

  8. Hamartoma mamario gigante: dos casos de una entidad rara

    OpenAIRE

    T.A. Gomes-Rodrigues; A. López-Ojeda; J. Muñoz i Vidal; M.T. Soler-Monsó; J.M. Serra-Payro; A. Guma-Martínez; F. Chavarría-Marín; M. Dewever

    2014-01-01

    El hamartoma gigante de la mama es una entidad clínico-patológica inusual que tiende a confundirse con otros tumores. A pesar del avance en las técnicas diagnósticas, su diagnóstico clínico es difícil y normalmente solo se confirma cuando se analiza toda la pieza de resección. El diagnóstico diferencial debe incluir entidades como el fibroadenoma, lipoma, tumor phyllodes y diversos tipos de carcinomas. Presentamos 2 casos de hamartoma gigante de mama en mujeres de edad media, de los cuales un...

  9. Macrodystrophia Lipomatosa: An Unusual Cause of Localized Gigantism.

    Science.gov (United States)

    Maheswari, S Uma; Sampath, V; Ramesh, A; Manoharan, K

    2016-01-01

    Macrodystrophia lipomatosa (MDL) is a rare congenital form of localized gigantism characterized by progressive overgrowth of all mesenchymal elements with a disproportionate increase in fibro adipose tissue. Here we report a case of 20 years old male who presented with history of painless gradual enlargement of entire left upper limb since childhood. Magnetic resonance imaging and histopathology confirmed the diagnosis of macrodystrophia lipomatosa. This condition has to be differentiated from other causes of localized gigantism, since these conditions differ in their course, prognosis, complications and treatment.

  10. Macrodystrophia lipomatosa: An unusual cause of localized gigantism

    Directory of Open Access Journals (Sweden)

    S Uma Maheswari

    2016-01-01

    Full Text Available Macrodystrophia lipomatosa (MDL is a rare congenital form of localized gigantism characterized by progressive overgrowth of all mesenchymal elements with a disproportionate increase in fibro adipose tissue. Here we report a case of 20 years old male who presented with history of painless gradual enlargement of entire left upper limb since childhood. Magnetic resonance imaging and histopathology confirmed the diagnosis of macrodystrophia lipomatosa. This condition has to be differentiated from other causes of localized gigantism, since these conditions differ in their course, prognosis, complications and treatment.

  11. Evidence for autosomal recessive inheritance in cerebral gigantism

    Science.gov (United States)

    Nevo, S.; Zeltzer, M.; Benderly, A.; Levy, J.

    1974-01-01

    Three cases of cerebral gigantism, two sibs and their double first cousin, are described in a large inbred family from Israel. Two of the three were observed and diagnosed at birth and two were followed for two years. They all presented the signs and symptoms considered typical of this syndrome, as well as some of the less frequent findings. Generalized oedema and flexion contractures of the feet were observed in two of the three at birth. This has not hitherto been reported in cases of cerebral gigantism, of whom only a few have been observed and diagnosed at birth. Autosomal recessive inheritance is clearly implied in this family. Images PMID:4841084

  12. Myoadenylate deaminase deficiency, hypertrophic cardiomyopathy and gigantism syndrome.

    Science.gov (United States)

    Skyllouriotis, M L; Marx, M; Bittner, R E; Skyllouriotis, P; Gross, M; Wimmer, M

    1997-07-01

    We report a 20-year-old man with gigantism syndrome, hypertrophic cardiomyopathy, muscle weakness, exercise intolerance, and severe psychomotor retardation since childhood. Histochemical and biochemical analysis of skeletal muscle biopsy revealed myoadenylate deaminase deficiency; molecular genetic analysis confirmed the diagnosis of primary (inherited) myoadenylate deaminase deficiency. Plasma, urine, and muscle carnitine concentrations were reduced. L-Carnitine treatment led to gradual improvement in exercise tolerance and cognitive performance; plasma and tissue carnitine levels returned to normal, and echocardiographic evidence of left ventricular hypertrophy disappeared. The combination of inherited myoadenylate deaminase deficiency, gigantism syndrome and carnitine deficiency has not previously been described.

  13. Bivalves: From individual to population modelling

    Science.gov (United States)

    Saraiva, S.; van der Meer, J.; Kooijman, S. A. L. M.; Ruardij, P.

    2014-11-01

    An individual based population model for bivalves was designed, built and tested in a 0D approach, to simulate the population dynamics of a mussel bed located in an intertidal area. The processes at the individual level were simulated following the dynamic energy budget theory, whereas initial egg mortality, background mortality, food competition, and predation (including cannibalism) were additional population processes. Model properties were studied through the analysis of theoretical scenarios and by simulation of different mortality parameter combinations in a realistic setup, imposing environmental measurements. Realistic criteria were applied to narrow down the possible combination of parameter values. Field observations obtained in the long-term and multi-station monitoring program were compared with the model scenarios. The realistically selected modeling scenarios were able to reproduce reasonably the timing of some peaks in the individual abundances in the mussel bed and its size distribution but the number of individuals was not well predicted. The results suggest that the mortality in the early life stages (egg and larvae) plays an important role in population dynamics, either by initial egg mortality, larvae dispersion, settlement failure or shrimp predation. Future steps include the coupling of the population model with a hydrodynamic and biogeochemical model to improve the simulation of egg/larvae dispersion, settlement probability, food transport and also to simulate the feedback of the organisms' activity on the water column properties, which will result in an improvement of the food quantity and quality characterization.

  14. Microplastics in bivalves cultured for human consumption.

    Science.gov (United States)

    Van Cauwenberghe, Lisbeth; Janssen, Colin R

    2014-10-01

    Microplastics are present throughout the marine environment and ingestion of these plastic particles (microplastics in two species of commercially grown bivalves: Mytilus edulis and Crassostrea gigas. Microplastics were recovered from the soft tissues of both species. At time of human consumption, M. edulis contains on average 0.36 ± 0.07 particles g(-1) (wet weight), while a plastic load of 0.47 ± 0.16 particles g(-1) ww was detected in C. gigas. As a result, the annual dietary exposure for European shellfish consumers can amount to 11,000 microplastics per year. The presence of marine microplastics in seafood could pose a threat to food safety, however, due to the complexity of estimating microplastic toxicity, estimations of the potential risks for human health posed by microplastics in food stuffs is not (yet) possible. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Metabolites of saxitoxin analogues in bivalves contaminated by Gymnodinium catenatum.

    Science.gov (United States)

    Vale, Paulo

    2010-01-01

    Bivalve metabolites of saxitoxin analogues, not present in microalgae, were recently described as an important toxin fraction in mussels contaminated by Alexandrium tamarense. These possess very low fluorescence, and require mass spectrometry detection. HILIC-MS was implemented to look for these metabolites in bivalves contaminated during Gymnodinium catenatum blooms at the Portuguese coast. The presence of M1 was tentatively identified in several bivalves, ranging from estuarine (Mytilus galloprovinciallis, Cerastoderma edule and Ruditapes decussatus) to oceanic habitat (Donax trunculus and Ensis spp.). It was hypothesized that M1 could contribute to an important fraction of the profile of STX analogues. M1 was more abundant in estuarine bivalves that retain longer PSP toxins, in the following order: mussels>cockles>clams. These data highlight that the study by fluorimetry alone of the carbamoyl, N-sulfocarbamoyl, and decarbamoyl families is manifestly insufficient to fully understand toxin dynamics in bivalves feeding on G. catenatum without a proper study of hydroxybenzoate and hydroxylated M-toxins.

  16. 1er. Taller internacional sobre oso hormiguero gigante (Myrmecophaga tridactyla)

    OpenAIRE

    M.V. Guillermo Pérez Jimeno

    2008-01-01

    ResumenLos pasados días 2 y 3 de noviembre se llevó a cabo el 1er. Taller internacional sobre oso hormiguero gigante (Myrmecophaga tridactyla), en instalaciones del Zoológico de Florencio Varela. Participaron activamente representantes de Brasil, Colombia, Holanda, Alemania y Argentina.

  17. Sotos syndrome (cerebral gigantism: analysis of 8 cases

    Directory of Open Access Journals (Sweden)

    Melo Débora Gusmão

    2002-01-01

    Full Text Available Sotos syndrome or cerebral gigantism is characterized by macrocephaly, overgrowth, mental retardation and central nervous system abnormalities. Congenital heart defects may be present. We report 8 patients with this syndrome and relate their clinical features, neuroimaging and echocardiographic findings.

  18. A rare association of localized gigantism with tuberous sclerosis.

    Science.gov (United States)

    Reddy, B S; Sheriff, M O; Garg, B R; Ratnakar, C

    1992-10-01

    An unusual association of localized gigantism with hypertrophy of the long bones and soft tissues in the left lower limb in an 18-year-old male with tuberous sclerosis (TS) is reported. The significance of this association is discussed from the point of view of its common neural crest origin during embryogenesis.

  19. First observations of Gigantic Jets from Monsoon Thunderstorms over India

    Science.gov (United States)

    Singh, Rajesh; Maurya, Ajeet; Chanrion, Olivier; Neubert, Torsten; Cummer, Steven; Mlynarczyk, Janusz; Bór, József; Siingh, Devendraa; Cohen, Morris; Kumar, Sushil

    2016-04-01

    Gigantic Jets are electric discharges from thunderstorm cloud tops to the bottom of the ionosphere at ~80 km altitude. After their first discovery in 2001, relatively few observations have been reported. Most of these are from satellites at large distances and a few tens from the ground at higher spatial resolution. Here we report the first Gigantic Jets observed in India from two thunderstorm systems that developed over the land surface from monsoon activity, each storm producing two Gigantic Jets. The jets were recorded by a video camera system at standard video rate (20 ms exposure) at a few hundred km distance. ELF measurements suggest that the jets are of the usual negative polarity and that they develop in less than 40 ms, which is faster than most jets reported in the past. The jets originate from the leading edge of a slowly drifting convective cloud complex close to the highest regions of the clouds and carry ~25 Coulomb of charge to the ionosphere. One jet has a markedly horizontal displacement that we suggest is caused by a combination of close-range cloud electric fields at inception, and longer-range cloud fields at larger distances during full development. The Gigantic Jets are amongst the few that have been observed over land.

  20. Predation and habitat modification synergistically interact to control bivalve recruitment on intertidal mudflats

    NARCIS (Netherlands)

    van der Heide, T.; Tielens, E.; van der Zee, E.M.; Weerman, E.J.; Holthuijsen, S.; Eriksson, B.K.; Piersma, T.; van de Koppel, J.; Olff, H.

    2014-01-01

    Bivalves are key components of coastal ecosystems because they link pelagic and benthic food webs, and shape the landscape through habitat modification. Nevertheless, many bivalve stocks have dramatically declined, and recruitment failure due to (anthropogenically-) increased predation by

  1. Predation and habitat modification synergistically interact to control bivalve recruitment on intertidal mudflats

    NARCIS (Netherlands)

    van der Heide, Tjisse; Tielens, Elske; van der Zee, Els; Weerman, Ellen J.; Holthuijsen, Sander; Eriksson, Britas Klemens; Piersma, Theun; van de Koppel, Johan; Olff, Han

    Bivalves are key components of coastal ecosystems because they link pelagic and benthic food webs, and shape the landscape through habitat modification. Nevertheless, many bivalve stocks have dramatically declined, and recruitment failure due to (anthropogenically-) increased predation by

  2. 76 FR 65200 - Risk Assessment on Norovirus in Bivalve Molluscan Shellfish: Request for Comments and for...

    Science.gov (United States)

    2011-10-20

    ... transmission of norovirus from infected or ill food workers in food manufacturing or retail establishments to... Molluscan Shellfish Contamination Levels During Food Preparation and Bivalve Molluscan Shellfish Consumption... and other factors influencing bivalve molluscan shellfish contamination levels during food preparation...

  3. Gigantism in sibling unrelated to multiple endocrine neoplasia: case report.

    Science.gov (United States)

    Matsuno, A; Teramoto, A; Yamada, S; Kitanaka, S; Tanaka, T; Sanno, N; Osamura, R Y; Kirino, T

    1994-11-01

    The cases of gigantism sisters with somatotroph adenomas unrelated to multiple endocrine neoplasia (MEN) Type 1 are reported. The sisters grew rapidly since they were 5 or 6 years old and were diagnosed to have gigantism with pituitary adenoma by computed tomographic scan and magnetic resonance imaging. A serum endocrinological examination showed the elevated growth hormone values. After thyroxine-releasing hormone stimulation, growth hormone values exhibited a paradoxical rise. They were supposed to be unrelated to MEN Type 1, because analysis of the 11th chromosomes and the other endocrine functions were normal. They were operated on by the transphenoidal method. Immunohistochemical staining of both tumor specimens confirmed somatotroph adenomas. Pituitary adenoma associated with MEN Type 1 is a well-recognized entity. However, the sporadic occurrence of pituitary adenoma unrelated to MEN Type 1, especially in siblings, is extremely rare. Fifteen cases of pituitary adenomas in siblings were described in the literature. As for gigantism, only two brothers were reported. Our case of gigantism sisters is the second sporadic case. In our review of the isolated cases of pituitary adenoma in siblings described in the literature, 12 (70%) of 17 cases including ours are acromegaly or gigantism. This incidence is much higher than that of MEN Type 1 patients with pituitary adenomas. The cause of the familial occurrence of pituitary adenomas is still unclear, although autosomal recessive inheritance has been suggested. It has been stated that point mutations in codon 201 or 227 of the Gs alpha gene located in chromosome 20 were found in about 35 to 40% of somatotroph adenomas.(ABSTRACT TRUNCATED AT 250 WORDS)

  4. Artificially evolved functional shell morphology of burrowing bivalves

    DEFF Research Database (Denmark)

    Germann, D. P.; Schatz, W.; Hotz, Peter Eggenberger

    2014-01-01

    dimensional (3D) objects, the first ever artificial evolution of a physical bivalve shell was performed. The result was a vertically flattened shell occupying only the top sediment layers. Insufficient control of the sediment was the major limitation of the setup and restricted the significance of the results......, there are almost no studies experimentally testing their dynamic properties. To investigate the functional morphology of the bivalve shell, we employed a synthetic methodology and built an experimental setup to simulate the burrowing process. Using an evolutionary algorithm and a printer that prints three...

  5. Modeling the carbon isotope composition of bivalve shells (Invited)

    Science.gov (United States)

    Romanek, C.

    2010-12-01

    The stable carbon isotope composition of bivalve shells is a valuable archive of paleobiological and paleoenvironmental information. Previous work has shown that the carbon isotope composition of the shell is related to the carbon isotope composition of dissolved inorganic carbon (DIC) in the ambient water in which a bivalve lives, as well as metabolic carbon derived from bivalve respiration. The contribution of metabolic carbon varies among organisms, but it is generally thought to be relatively low (e.g., 90%) in the shells from terrestrial organisms. Because metabolic carbon contains significantly more C-12 than DIC, negative excursions from the expected environmental (DIC) signal are interpreted to reflect an increased contribution of metabolic carbon in the shell. This observation contrasts sharply with modeled carbon isotope compositions for shell layers deposited from the inner extrapallial fluid (EPF). Previous studies have shown that growth lines within the inner shell layer of bivalves are produced during periods of anaerobiosis when acidic metabolic byproducts (e.g., succinic acid) are neutralized (or buffered) by shell dissolution. This requires the pH of EPF to decrease below ambient levels (~7.5) until a state of undersaturation is achieved that promotes shell dissolution. This condition may occur when aquatic bivalves are subjected to external stressors originating from ecological (predation) or environmental (exposure to atm; low dissolved oxygen; contaminant release) pressures; normal physiological processes will restore the pH of EPF when the pressure is removed. As a consequence of this process, a temporal window should also exist in EPF at relatively low pH where shell carbonate is deposited at a reduced saturation state and precipitation rate. For example, EPF chemistry should remain slightly supersaturated with respect to aragonite given a drop of one pH unit (6.5), but under closed conditions, equilibrium carbon isotope fractionation

  6. Lower Oligocene bivalves of Ramanian Stage from Kachchh ...

    Indian Academy of Sciences (India)

    Sehe area of western Kachchh considered their. Bed Nos. 4 and 5 as .... with very thin population. The Bermoti stream ...... Recent; Indo–Pacific. Subgenus: .... Type species: Cardium discors Lamarck' 1805; T. Eocene–Miocene; Europe–Asia ..... Shuto Tsugio 1971 Neogene Bivalves from Panay Island, the. Philippines.

  7. Organisms associated with the sandy-beach bivalve Donax serra ...

    African Journals Online (AJOL)

    57: 134-136. BROWN, AC. & WEBB, S.c. 1994. Organisms associated \\.,.,ith burrowing whelks of the genus Bullia. S Afr. 1. Zool. 29: 144-151. BROWN, A.C., STENTON-DOZEY, J.~.E. & TRUEMAN, E.R.. 1989. Sandy-beach bivalves and gastropods; a comparison between Donax serra and Ruilia digitalis. Adv. mar. Bioi. 25:.

  8. Seasonal variability in somatic and reproductive investment of the bivalve

    NARCIS (Netherlands)

    Santos, S.; Cardoso, J.F.M.F.; Carvalho, C.; Luttikhuizen, P.C.; van der Veer, H.W.

    2011-01-01

    Monthly investment in soma and gonads in the bivalve Scrobicularia plana is described for three populations along its distributional range: Minho estuary, Portugal; Westerschelde estuary, The Netherlands and Buvika estuary, Norway. Seasonal cycles in body mass (BMI), somatic mass (SMI) and

  9. Defects in codoped NiO with gigantic dielectric response

    Science.gov (United States)

    Wu, Ping; Ligatchev, Valeri; Yu, Zhi Gen; Zheng, Jianwei; Sullivan, Michael B.; Zeng, Yingzhi

    2009-06-01

    We combine first-principles, statistical, and phenomenological methods to investigate the electronic and dielectric properties of NiO and clarify the nature of the gigantic dielectric response in codoped NiO. Unlike previous models which are dependent on grain-boundary effects, our model based on small polaron hopping in homogeneous material predicts the dielectric permittivity (104-5) for heavily Li- and MD -codoped NiO (MD=Ti,Al,Si) . Furthermore, we reproduce the experimental trends in dielectric properties as a function of the dopants nature and their concentrations, as well as the reported activation energies for the relaxation in Li- and Ti-codoped NiO (0.308 eV or 0.153 eV depending on the Fermi-level position). In this study, we demonstrate that small polaron hopping on dopant levels is the dominant mechanism for the gigantic dielectric response in these codoped NiO.

  10. Tyrannosauroid integument reveals conflicting patterns of gigantism and feather evolution.

    Science.gov (United States)

    Bell, Phil R; Campione, Nicolás E; Persons, W Scott; Currie, Philip J; Larson, Peter L; Tanke, Darren H; Bakker, Robert T

    2017-06-01

    Recent evidence for feathers in theropods has led to speculations that the largest tyrannosaurids, including Tyrannosaurus rex , were extensively feathered. We describe fossil integument from Tyrannosaurus and other tyrannosaurids ( Albertosaurus, Daspletosaurus, Gorgosaurus and Tarbosaurus ), confirming that these large-bodied forms possessed scaly, reptilian-like skin. Body size evolution in tyrannosauroids reveals two independent occurrences of gigantism; specifically, the large sizes in Yutyrannus and tyrannosaurids were independently derived. These new findings demonstrate that extensive feather coverings observed in some early tyrannosauroids were lost by the Albian, basal to Tyrannosauridae. This loss is unrelated to palaeoclimate but possibly tied to the evolution of gigantism, although other mechanisms exist. © 2017 The Author(s).

  11. Management of type 2 diabetes mellitus associated with pituitary gigantism.

    Science.gov (United States)

    Ali, Omar; Banerjee, Swati; Kelly, Daniel F; Lee, Phillip D K

    2007-01-01

    Pituitary gigantism, a condition of endogenous growth hormone (GH) hypersecretion prior to epiphyseal closure, is a rare condition. In the adult condition of GH excess, acromegaly, the occurrence of type 2 diabetes mellitus (T2DM) and diabetic ketoacidosis (DKA) have been reported, with resolution following normalization of GH levels. We report the case of a 16-year-old male with pituitary gigantism due to a large invasive suprasellar adenoma who presented with T2DM and DKA. Despite surgical de-bulking, radiotherapy and medical treatment with cabergoline and pegvisomant, GH and insulin-like growth factor-I (IGF-I) levels remained elevated. However, the T2DM and recurrent DKA were successfully managed with metformin and low-dose glargine insulin, respectively. We review the pathophysiology of T2DM and DKA in growth hormone excess and available treatment options.

  12. Multiple origins of gigantism in stem baleen whales

    Science.gov (United States)

    Tsai, Cheng-Hsiu; Kohno, Naoki

    2016-12-01

    Living baleen whales (Mysticeti) include the world's largest animals to have ever lived—blue whales ( Balaenoptera musculus) can reach more than 30 m. However, the gigantism in baleen whales remains little explored. Here, we compiled all published stem mysticetes from the Eocene and Oligocene and then mapped the estimated body size onto different phylogenies that suggest distinct evolutionary histories of baleen whales. By assembling all known stem baleen whales, we present three novel findings in early mysticete evolution. Results show that, regardless of different phylogenetic scenarios, large body size (more than 5-m long) evolved multiple times independently in their early evolutionary history. For example, the earliest known aetiocetid ( Fucaia buelli, 33-31 Ma) was small in size, about 2 m, and a later aetiocetid ( Morawanocetus-like animal, 26-23 Ma) can reach 8-m long—almost four times the size of Fucaia buelli—suggesting an independent gigantism in the aetiocetid lineage. In addition, our reconstruction of ancestral state demonstrates that the baleen whales originated from small body size (less than 5 m) rather than large body size as previously acknowledged. Moreover, reconstructing the evolution of body size in stem baleen whales suggests that the initial pulse of mysticete gigantism started at least back to the Paleogene and in turn should help to understand the origin, pattern, and process of the extreme gigantism in the crown baleen whales. This study illustrates that Cope's rule is insufficient to explain the evolution of body size in a group that comprises the largest animals in the history of life, although currently the lack of exact ancestor-descendant relationships remains to fully reveal the evolutionary history of body size.

  13. Breast gigantism induced by D-penicillamine: case report

    International Nuclear Information System (INIS)

    Cha, Ji Hyeon; Kim, Hak Hee; Kim, Sun Mi; Seo, Myung Hee; Yoon, Hoi Soo

    2004-01-01

    D-penicillamine, a chelating agent of copper, is the drug of choice for the treatment of Wilson's disease. Breast enlargement is a rare complication arising from its use, and we report a case of breast gigantism which developed after it had been used for ten months to treat this condition. Mammography demonstrated bilaterally enlarged dense breasts; ultrasonography, similarly, demonstrated enlargement, revealing the presence of a mass, shown at biopsy to be benign, in the left one

  14. Breast gigantism induced by D-penicillamine: case report

    Energy Technology Data Exchange (ETDEWEB)

    Cha, Ji Hyeon; Kim, Hak Hee; Kim, Sun Mi; Seo, Myung Hee; Yoon, Hoi Soo [College of Medicine, Ulsan Univ., Seoul (Korea, Republic of)

    2004-03-01

    D-penicillamine, a chelating agent of copper, is the drug of choice for the treatment of Wilson's disease. Breast enlargement is a rare complication arising from its use, and we report a case of breast gigantism which developed after it had been used for ten months to treat this condition. Mammography demonstrated bilaterally enlarged dense breasts; ultrasonography, similarly, demonstrated enlargement, revealing the presence of a mass, shown at biopsy to be benign, in the left one.

  15. Proteus syndrome: A rare cause of gigantic limb

    OpenAIRE

    Nandini Chakrabarti; Chandan Chattopadhyay; Majhi Bhuban; Salil Kumar Pal

    2014-01-01

    A congenital disorder with variable manifestations, including partial gigantism of the hands and feet with hypertrophy of soles, nevi, hemihypertrophy, gynecomastia, macrocephaly and other skull abnormalities, and abdominal lipomatosis. The cause is unknown, although a genetic origin, generally of autosomal-dominant transmission, has been conjectured. Symptoms can be treated, but there is no known cure. We present the case of a young male with grotesque overgrowth of the right lower limb, spl...

  16. Macrodystrophia lipomatosa: An unusual cause of localized gigantism

    OpenAIRE

    S Uma Maheswari; V Sampath; A Ramesh; K Manoharan

    2016-01-01

    Macrodystrophia lipomatosa (MDL) is a rare congenital form of localized gigantism characterized by progressive overgrowth of all mesenchymal elements with a disproportionate increase in fibro adipose tissue. Here we report a case of 20 years old male who presented with history of painless gradual enlargement of entire left upper limb since childhood. Magnetic resonance imaging and histopathology confirmed the diagnosis of macrodystrophia lipomatosa. This condition has to be differentiated fro...

  17. Ocean Acidification Has Multiple Modes of Action on Bivalve Larvae.

    Science.gov (United States)

    Waldbusser, George G; Hales, Burke; Langdon, Chris J; Haley, Brian A; Schrader, Paul; Brunner, Elizabeth L; Gray, Matthew W; Miller, Cale A; Gimenez, Iria; Hutchinson, Greg

    2015-01-01

    Ocean acidification (OA) is altering the chemistry of the world's oceans at rates unparalleled in the past roughly 1 million years. Understanding the impacts of this rapid change in baseline carbonate chemistry on marine organisms needs a precise, mechanistic understanding of physiological responses to carbonate chemistry. Recent experimental work has shown shell development and growth in some bivalve larvae, have direct sensitivities to calcium carbonate saturation state that is not modulated through organismal acid-base chemistry. To understand different modes of action of OA on bivalve larvae, we experimentally tested how pH, PCO2, and saturation state independently affect shell growth and development, respiration rate, and initiation of feeding in Mytilus californianus embryos and larvae. We found, as documented in other bivalve larvae, that shell development and growth were affected by aragonite saturation state, and not by pH or PCO2. Respiration rate was elevated under very low pH (~7.4) with no change between pH of ~ 8.3 to ~7.8. Initiation of feeding appeared to be most sensitive to PCO2, and possibly minor response to pH under elevated PCO2. Although different components of physiology responded to different carbonate system variables, the inability to normally develop a shell due to lower saturation state precludes pH or PCO2 effects later in the life history. However, saturation state effects during early shell development will carry-over to later stages, where pH or PCO2 effects can compound OA effects on bivalve larvae. Our findings suggest OA may be a multi-stressor unto itself. Shell development and growth of the native mussel, M. californianus, was indistinguishable from the Mediterranean mussel, Mytilus galloprovincialis, collected from the southern U.S. Pacific coast, an area not subjected to seasonal upwelling. The concordance in responses suggests a fundamental OA bottleneck during development of the first shell material affected only by

  18. Ocean Acidification Has Multiple Modes of Action on Bivalve Larvae.

    Directory of Open Access Journals (Sweden)

    George G Waldbusser

    Full Text Available Ocean acidification (OA is altering the chemistry of the world's oceans at rates unparalleled in the past roughly 1 million years. Understanding the impacts of this rapid change in baseline carbonate chemistry on marine organisms needs a precise, mechanistic understanding of physiological responses to carbonate chemistry. Recent experimental work has shown shell development and growth in some bivalve larvae, have direct sensitivities to calcium carbonate saturation state that is not modulated through organismal acid-base chemistry. To understand different modes of action of OA on bivalve larvae, we experimentally tested how pH, PCO2, and saturation state independently affect shell growth and development, respiration rate, and initiation of feeding in Mytilus californianus embryos and larvae. We found, as documented in other bivalve larvae, that shell development and growth were affected by aragonite saturation state, and not by pH or PCO2. Respiration rate was elevated under very low pH (~7.4 with no change between pH of ~ 8.3 to ~7.8. Initiation of feeding appeared to be most sensitive to PCO2, and possibly minor response to pH under elevated PCO2. Although different components of physiology responded to different carbonate system variables, the inability to normally develop a shell due to lower saturation state precludes pH or PCO2 effects later in the life history. However, saturation state effects during early shell development will carry-over to later stages, where pH or PCO2 effects can compound OA effects on bivalve larvae. Our findings suggest OA may be a multi-stressor unto itself. Shell development and growth of the native mussel, M. californianus, was indistinguishable from the Mediterranean mussel, Mytilus galloprovincialis, collected from the southern U.S. Pacific coast, an area not subjected to seasonal upwelling. The concordance in responses suggests a fundamental OA bottleneck during development of the first shell material

  19. Indian marine bivalves: Potential source of antiviral drugs

    Digital Repository Service at National Institute of Oceanography (India)

    Chatterji, A.; Ansari, Z.A.; Ingole, B.S.; Bichurina, M.A.; Sovetova, M.; Boikov, Y.A.

    in large quantities by traditional methods and sold live in the market for human consumption. The economically important sp e cies of marine bivalves are green mussel ( Perna viridis ), e s tuarine oyster ( Crassostrea madrasensis ), giant oyster... in developing an effecti ve drug has been the unique characteristics of antigenic variation of virus resulting in the emergence of new variant virus strains 14 . There are a number of antiviral drugs introduced in the market such as tricyclic sy m- metric...

  20. Light indirectly mediates bivalve habitat modification and impacts on seagrass

    DEFF Research Database (Denmark)

    Castorani, Max C. N.; Glud, Ronnie; Hasler-Sheetal, Harald

    2015-01-01

    Environmental context may influence the sign, strength, andmechanisms of species interactions but few studies have experimentally tested the potential for abiotic conditions to mediate interactions through multiple cooccurring stress pathways. Abiotic conditionsmay mediate species interactions...... by directly or indirectly influencing the effects of habitat-modifying organisms that are capable of simultaneously ameliorating and exacerbating multiple stressors. Itwas hypothesized that light availability changes seagrassmetabolismand thereby indirectly regulates bivalve habitat modification...

  1. Environmentally applications of invasive bivalves for water and wastewater decontamination.

    Science.gov (United States)

    Gomes, João; Matos, Ana; Quinta-Ferreira, Rosa M; Martins, Rui C

    2018-07-15

    The environmental and economic impact of invasive bivalve species implies the development of suitable pest management strategies. Chemical control is the most usual approach. However, the production of toxic intermediates as well as the unavoidable impact over non target biota is of special concern. Another approach consists on the physical removal of the animals from the invaded sites. The high biofiltration and bioaccumulation capacity of such animals make them interesting for the removal of contaminants from water and wastewater. In this context, environmental applications can be given for these pests encompassing nutrients removal for the recovery of eutrophic sites, water disinfection, organic and metal contaminants abatement. These approaches may be integrated with pest management where the physical removed animals from the invaded spots could be used for assembling biofilter for water and wastewater decontamination. However, some drawbacks must be addressed before proposing such alternative. In fact, the further spreading of the bivalves into non-invaded sites must be avoided. Moreover, some operational questions must be addressed such as the fate of contaminated animals after biofiltration. Bearing in mind the interesting results already available in this subject, this paper aims to critically overview literature regarding the environmental applications of invasive bivalves. Copyright © 2018 Elsevier B.V. All rights reserved.

  2. Gigantism caused by growth hormone secreting pituitary adenoma

    OpenAIRE

    Rhee, Noorisaem; Jeong, Kumi; Yang, Eun Mi; Kim, Chan Jong

    2014-01-01

    Gigantism indicates excessive secretion of growth hormones (GH) during childhood when open epiphyseal growth plates allow for excessive linear growth. Case one involved a 14.7-year-old boy presented with extreme tall stature. His random serum GH level was 38.4 ng/mL, and failure of GH suppression was noted during an oral glucose tolerance test (OGTT; nadir serum GH, 22.7 ng/mL). Magnetic resonance imaging (MRI) of the brain revealed a 12-mm-sized pituitary adenoma. Transsphenoidal surgery was...

  3. Spontaneous endocrine cure of gigantism due to pituitary apoplexy.

    Science.gov (United States)

    Arisaka, O; Hall, R; Hughes, I A

    1983-10-08

    An 11 year old, tall boy presented with symptoms typical of pituitary apoplexy. A large necrotic and haemorrhagic tumour was removed, which was shown to be an adenoma secreting growth hormone and prolactin. Subsequent treatment comprised cranial irradiation and hormone replacement. Eighteen months after operation growth was static and plasma growth hormone and prolactin concentrations were undetectable. Treatment of pituitary apoplexy should comprise excision of the tumour and postoperative irradiation; such treatment after early recognition of the condition offers the best chance of preserving normal pituitary function in children with gigantism.

  4. Gigantic Jet Environments: A Meteorological Evaluation Using Reanalysis Data Sets

    Science.gov (United States)

    Splitt, M. E.; Lazarus, S. M.

    2017-12-01

    The meteorological conditions of gigantic jet (GJ) producing thunderstorms tend to be connected to maritime tropical environments. In particular, they have an affinity toward tropical disturbances including those with moderate values of upper tropospheric environmental wind shear. Wind shear related effects (including turbulence) in association with deep convection in these environments have been proposed as mechanisms for the arrangement of GJ favorable charge structures. This study focuses on a climatological evaluation in an effort to assess whether the proposed ingredients are consistent with observed GJ event regions. The Climate System Forecast System - Version 2 (CFSR V2) is used here to test for the proposed GJ conditions.

  5. Hereditary Gigantism-the biblical giant Goliath and his brothers.

    Science.gov (United States)

    Donnelly, Deirdre E; Morrison, Patrick J

    2014-05-01

    The biblical giant Goliath has an identifiable family tree suggestive of autosomal dominant inheritance. We suggest that he had a hereditary pituitary disorder possibly due to the AIP gene, causing early onset and familial acromegaly or gigantism. We comment on the evidence within the scriptures for his other relatives including a relative with six digits and speculate on possible causes of the six digits. Recognition of a hereditary pituitary disorder in the biblical Goliath and his family sheds additional information on his and other family members' battles with David and his relatives.

  6. The Oldest Recorded Case of Acromegaly and Gigantism in Iran.

    Science.gov (United States)

    Najjari, Mohsen

    2015-10-01

    Here we commemorate the character and academic authority of Prof. Zabiholah Gorban (1903-2006), the founder of Shiraz medical school. No doubt, in the scope of history of contemporary medicine, he has been efficient and effective. With respect to this fact, his article on a rare case described in Acta anatomica published in Iran in 1966, entitled (Observations on a giant skeleton) is browsed and reviewed. A case named Siah Khan with combined acromegaly and gigantism that appears to have letters to say still after nearly half a century.

  7. Macrodystrophia lipomatosa: a reconstructive approach to gigantism of the foot.

    Science.gov (United States)

    Watt, Andrew J; Chung, Kevin C

    2004-01-01

    Localized gigantism poses a challenging surgical dilemma, and it may be treated with amputation. This case report documents the application of a reconstructive approach to a severe case of pedal macrodystrophia lipomatosa in a 1-year-old girl. A series of 3 surgeries were designed to reduce the length, width, height, and overall bulk of the congenitally enlarged foot. The 3 procedures debulked the foot for normal ambulation and same-size shoe wear for both feet. The resulting functional and aesthetic improvements achieved through reconstructive treatment provided a desirable alternative to amputation.

  8. Proteus syndrome: A rare cause of gigantic limb

    Directory of Open Access Journals (Sweden)

    Nandini Chakrabarti

    2014-01-01

    Full Text Available A congenital disorder with variable manifestations, including partial gigantism of the hands and feet with hypertrophy of soles, nevi, hemihypertrophy, gynecomastia, macrocephaly and other skull abnormalities, and abdominal lipomatosis. The cause is unknown, although a genetic origin, generally of autosomal-dominant transmission, has been conjectured. Symptoms can be treated, but there is no known cure. We present the case of a young male with grotesque overgrowth of the right lower limb, splenomegaly and multiple nevi. Angiography revealed venous malformation within the limb. The findings are in conformity to the criteria for the Proteus syndrome.

  9. Spontaneous endocrine cure of gigantism due to pituitary apoplexy.

    Science.gov (United States)

    Arisaka, O; Hall, R; Hughes, I A

    1983-01-01

    An 11 year old, tall boy presented with symptoms typical of pituitary apoplexy. A large necrotic and haemorrhagic tumour was removed, which was shown to be an adenoma secreting growth hormone and prolactin. Subsequent treatment comprised cranial irradiation and hormone replacement. Eighteen months after operation growth was static and plasma growth hormone and prolactin concentrations were undetectable. Treatment of pituitary apoplexy should comprise excision of the tumour and postoperative irradiation; such treatment after early recognition of the condition offers the best chance of preserving normal pituitary function in children with gigantism. PMID:6311318

  10. Proteus syndrome: A rare cause of gigantic limb.

    Science.gov (United States)

    Chakrabarti, Nandini; Chattopadhyay, Chandan; Bhuban, Majhi; Pal, Salil Kumar

    2014-04-01

    A congenital disorder with variable manifestations, including partial gigantism of the hands and feet with hypertrophy of soles, nevi, hemihypertrophy, gynecomastia, macrocephaly and other skull abnormalities, and abdominal lipomatosis. The cause is unknown, although a genetic origin, generally of autosomal-dominant transmission, has been conjectured. Symptoms can be treated, but there is no known cure. We present the case of a young male with grotesque overgrowth of the right lower limb, splenomegaly and multiple nevi. Angiography revealed venous malformation within the limb. The findings are in conformity to the criteria for the Proteus syndrome.

  11. The Bivalve Production Chain in Santa Catarina, Brazil, and its Management and Operational Limitations

    OpenAIRE

    Gallon, Alessandra Vasconcelos; Universidade Federal do Ceará (UFC); Nascimento, Cristiano; Universidade Federal do Paraná - UFPR; Pfitscher, Elisete Dahmer; Universidade Federal de Santa Catarina

    2011-01-01

    Bivalve farming (mussels and oysters), a major component in the socio-economic development of the state of Santa Catarina, Brazil, combines the activities of public and private agencies in fish farming. Current analysis deals with the management and the operational limitations of the local bivalve production chain. Current exploratory research, undertaken by direct observations and the literature on the subject, employs data quality. Results show that the bivalve production chain, comprising ...

  12. Transsphenoidal microsurgery in the treatment of acromegaly and gigantism.

    Science.gov (United States)

    Arafah, B U; Brodkey, J S; Kaufman, B; Velasco, M; Manni, A; Pearson, O H

    1980-03-01

    Twenty-five patients with acromegaly and 3 patients with gigantism underwent transsphenoidal microsurgery in an attempt to remove the tumor and preserve normal pituitary function whenever possible. An adenoma was identified and removed in 27 of 28 patients. Evaluation 3--6 months postoperatively revealed a GH level less than 5 ng/ml in 29 patients, 5--10 ng/ml in 4 patients and 11--29 ng/ml in 4 other patients. Dynamics of GH secretion were normal in 11 patients who had normal pituitary function and are considered cured. Two patients with low or undetectable GH levels are also considered cured at the expense of being hypopituitary. Three of 7 patients with normal basal GH levels but abnormal dynamics of GH secretion relapsed within 1 yr. Eleven of the 13 patients considered cured did not have extrasellar extension, while 14 of the 15 patients not cured had extrasellar extension. Five patients who were not cured with surgery received radiation therapy. Three patients were treated with an ergot derivative, Lergotrile mesylate, after surgery and radiation therapy failed to normalize GH levels. Transsphenoidal microsurgery is an optimal form of therapy for patients with acromegaly or gigantism, especially those with no extrasellar extension. Dynamics of GH secretion are very useful in evaluating the completeness of adenoma removal.

  13. Evolution of gigantism in nine-spined sticklebacks.

    Science.gov (United States)

    Herczeg, Gábor; Gonda, Abigél; Merilä, Juha

    2009-12-01

    The relaxation of predation and interspecific competition are hypothesized to allow evolution toward "optimal" body size in island environments, resulting in the gigantism of small organisms. We tested this hypothesis by studying a small teleost (nine-spined stickleback, Pungitius pungitius) from four marine and five lake (diverse fish community) and nine pond (impoverished fish community) populations. In line with theory, pond fish tended to be larger than their marine or lake conspecifics, sometimes reaching giant sizes. In two geographically independent cases when predatory fish had been introduced into ponds, fish were smaller than those in nearby ponds lacking predators. Pond fish were also smaller when found in sympatry with three-spined stickleback (Gasterosteus aculeatus) than those in ponds lacking competitors. Size-at-age analyses demonstrated that larger size in ponds was achieved by both increased growth rates and extended longevity of pond fish. Results from a common garden experiment indicate that the growth differences had a genetic basis: pond fish developed two to three times higher body mass than marine fish during 36 weeks of growth under similar conditions. Hence, reduced risk of predation and interspecific competition appear to be chief forces driving insular body size evolution toward gigantism.

  14. Lower Oligocene bivalves of Ramanian Stage from Kachchh, Gujarat, India

    Science.gov (United States)

    Kachhara, R. P.; Jodhawat, R. L.; Devi, K. Bigyapati

    2012-04-01

    Marine Oligocene sequences in India outcrop only in western part of Kachchh. Earlier researchers have recognized the Oligocene strata under the Nari Series (Nagappa 1959; Chatterji and Mathur 1966). The Nari Series has a type area in Pakistan. It has two subdivisions - the Lower Nari (Lower Oligocene) and the Upper Nari (Upper Oligocene). It seems that there is no valid proof about the age of the Lower Nari due to lack of proper fauna (Eames 1975), and according to Pascoe (1962), the Upper Nari slightly transgress into Aquitanian (Lower Miocene), therefore, one has to be very cautious. Biswas and Raju (1971) reclassified the Oligocene strata of Kachchh and lithostratigraphically clubbed them as the Maniyara Fort Formation with type section along the Bermoti stream. This Formation has four members. The lower three members correspond to the Ramanian Stage (Lower Oligocene, Biswas 1971, 1973) while the uppermost to the Waiorian Stage (Upper Oligocene, Biswas 1965, 1971, 1973). The Ramanian Stage is characterized by large forams especially Nummulites fichteli, Nummulites fichteli intermedius, Lepidocyclina ( Eulepidina) dialata and Operculina sp. Several ostracods are also known to occur. Megafauna include bivalves, gastropods, echinoids, corals, mammals and reptiles. Concerning bivalves earlier researchers have recorded a few taxa namely Trisidos semitorta (Lamarck), Cubitostrea angulata (J de C Sowerby), Pecten ( Amussiopecten) labadyei d'Archiac and Haime, Periglypta puerpera (Linne') var. aglaurae Brongniart, Ostrea fraasi Mayer Eymer and listed Pecten laevicostatus J de C Sowerby, Callista pseudoumbonella Vredenburg and Clementia papyracea (Gray) from Kachchh as against overall 42 forms from the Nari Series as a whole (Vredenburg 1928). This tempted us to make an attempt to collect bivalve fauna systematically which are occurring prolifically in the Ramanian Stage. In the present work, for this purpose, sections are worked out around Lakhpat (23°50'N; 68°47'E

  15. A novel filtering mutualism between a sponge host and its endosymbiotic bivalves.

    Science.gov (United States)

    Tsubaki, Remi; Kato, Makoto

    2014-01-01

    Sponges, porous filter-feeding organisms consisting of vast canal systems, provide unique substrates for diverse symbiotic organisms. The Spongia (Spongia) sp. massive sponge is obligately inhabited by the host-specific endosymbiotic bivalve Vulsella vulsella, which benefits from this symbiosis by receiving protection from predators. However, whether the host sponge gains any benefit from this association is unclear. Considering that the bivalves exhale filtered water into the sponge body rather than the ambient environment, the sponge is hypothesized to utilize water exhaled by the bivalves to circulate water around its body more efficiently. We tested this hypothesis by observing the sponge aquiferous structure and comparing the pumping rates of sponges and bivalves. Observations of water currents and the sponge aquiferous structure revealed that the sponge had a unique canal system enabling it to inhale water exhaled from bivalves, indicating that the host sponge adapted morphologically to receive water from the bivalves. In addition, the volume of water circulating in the sponge body was dramatically increased by the water exhaled from bivalves. Therefore, this sponge-bivalve association can be regarded as a novel mutualism in which two filter-feeding symbionts promote mutual filtering rates. This symbiotic association should be called a "filtering mutualism".

  16. Development of human impact on suspension-feeding bivalves in coastal soft-bottom ecosystems

    NARCIS (Netherlands)

    Wolff, Wim J.; Dame, RF; Olenin, S

    2005-01-01

    Suspension-feeding bivalves often may occur in large concentrations ('beds') on tidal flats. This makes them attractive for human consumers and the archaeological record shows collection of bivalves by coastal populations already tens of thousands of years ago. In modem time human interference with

  17. Effect of dietary polyunsaturated fatty acids on reproductive output and larval growth of bivalves

    NARCIS (Netherlands)

    Hendriks, I.E.; Van Duren, L.A.; Herman, P.M.J.

    2003-01-01

    The pre-spawning condition of adult bivalves is influenced by quantity and quality of available food. For bivalves, the essential polyunsaturated fatty acids (PUFAs) eicosapentaenoic acid (EPA) 20:5(n-3) and docosahexaenoic acid (DHA) 22:6(n-3) are presumed to determine the nutritional value of

  18. Condiloma acuminado gigante (tumor de Buschke-Lowenstein

    Directory of Open Access Journals (Sweden)

    Ibis Beltrán Pérez

    Full Text Available Se presenta un paciente masculino de 72 años de edad de la raza blanca, que es remitido al Servicio de Coloproctología por presentar desde hace más de un año, aumento de volumen alrededor del ano que le dificulta la defecación y sentarse. Se han realizado múltiples tratamientos tópicos con resultados no satisfactorios por el servicio de dermatología. Se le realiza estudio histopatológico de la lesión y se obtuvo un condiloma acuminado gigante (tumor de Buschke-Lowenstein. Se ha dado seguimiento sin presentarse hasta el momento recurrencia. El tumor de Buschke-Lowenstein es una entidad rara, considerada una lesión premaligna provocada por el papiloma virus humano. Hasta el momento no se ha podido encontrar el tratamiento ideal y continúa presentando una alta tasa de recurrencia.

  19. Gigantic Jets and the Tropical Paradigm: A Satellite Perspective

    Science.gov (United States)

    Lazarus, S. M.; Splitt, M. E.

    2017-12-01

    While not exclusively oceanic, gigantic jets (GJ) appear to have a preference for the tropical environment. In particular, a number of GJs have been observed in conjunction with tropical disturbances (i.e., weak tropical storms, depressions, and remnant lows). Given the remote aspect of TC convection and general lack of radar coverage, we explore this subset of events via analysis of their infrared and water vapor satellite presentations. The satellite perspective is relevant given that storm top mixing (dilution) of charge associated with storm-scale turbulence in this portion of the storm is thought to be connected to GJs. The thunderstorm overshoot, upper level divergence / outflow are examined in an effort to better understand the tropical paradigm. Specifically, an analysis of cloud top temperature, anvil expansion rates and asymmetries as well as placement of the GJ events with respect to the large (storm) scale circulation will be conducted.

  20. Model of UV flashes due to gigantic blue jets

    International Nuclear Information System (INIS)

    Milikh, G M; Shneider, M N

    2008-01-01

    Analysis of UV flashes observed by the UV detector on board the 'Tatiana' microsatellite suggests, based on their location, pulse width and energy of the source of the photons, that the flashes were generated by gigantic blue jets (GBJs). Presented in this paper is a numerical model of UV flashes due to a bunch of long streamers which form a leader, a prong such as that observed in a GBJ. Using a previously developed model of upward propagation of a long streamer in the exponential atmosphere the paper describes temporal evolution of the UV flux generated by a bunch of long streamers, in the given spectral range 300-400 nm used by the UV detector on board 'Tatiana'. The model is in agreement with the observations.

  1. Gate-tunable gigantic lattice deformation in VO2

    International Nuclear Information System (INIS)

    Okuyama, D.; Hatano, T.; Nakano, M.; Takeshita, S.; Ohsumi, H.; Tardif, S.; Shibuya, K.; Yumoto, H.; Koyama, T.; Ohashi, H.; Takata, M.; Kawasaki, M.; Tokura, Y.; Iwasa, Y.; Arima, T.

    2014-01-01

    We examined the impact of electric field on crystal lattice of vanadium dioxide (VO 2 ) in a field-effect transistor geometry by in-situ synchrotron x-ray diffraction measurements. Whereas the c-axis lattice parameter of VO 2 decreases through the thermally induced insulator-to-metal phase transition, the gate-induced metallization was found to result in a significant increase of the c-axis length by almost 1% from that of the thermally stabilized insulating state. We also found that this gate-induced gigantic lattice deformation occurs even at the thermally stabilized metallic state, enabling dynamic control of c-axis lattice parameter by more than 1% at room temperature

  2. Gigantism Precedes Filter Feeding in Baleen Whale Evolution.

    Science.gov (United States)

    Fordyce, R Ewan; Marx, Felix G

    2018-05-21

    Baleen whales (Mysticeti) are the largest animals on Earth, thanks to their ability to filter huge volumes of small prey from seawater. Mysticetes appeared during the Late Eocene, but evidence of their early evolution remains both sparse and controversial [1, 2], with several models competing to explain the origin of baleen-based bulk feeding [3-6]. Here, we describe a virtually complete skull of Llanocetus denticrenatus, the second-oldest (ca. 34 Ma) mysticete known. The new material represents the same individual as the type and only specimen, a fragmentary mandible. Phylogenetic analysis groups Llanocetus with the oldest mysticete, Mystacodon selenensis [2], into the basal family Llanocetidae. Llanocetus is gigantic (body length ∼8 m) compared to other early mysticetes [7-9]. The broad rostrum has sharp, widely spaced teeth with marked dental abrasion and attrition, suggesting biting and occlusal shearing. As in extant mysticetes, the palate bears many sulci, commonly interpreted as osteological correlates of baleen [3]. Unexpectedly, these sulci converge on the upper alveoli, suggesting a peri-dental blood supply to well-developed gums, rather than to inter-alveolar racks of baleen. We interpret Llanocetus as a raptorial or suction feeder, revealing that whales evolved gigantism well before the emergence of filter feeding. Rather than driving the origin of mysticetes, baleen and filtering most likely only arose after an initial phase of suction-assisted raptorial feeding [2, 4, 5]. This scenario differs strikingly from that proposed for odontocetes, whose defining adaptation-echolocation-was present even in their earliest representatives [10]. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Gigantism caused by growth hormone secreting pituitary adenoma.

    Science.gov (United States)

    Rhee, Noorisaem; Jeong, Kumi; Yang, Eun Mi; Kim, Chan Jong

    2014-06-01

    Gigantism indicates excessive secretion of growth hormones (GH) during childhood when open epiphyseal growth plates allow for excessive linear growth. Case one involved a 14.7-year-old boy presented with extreme tall stature. His random serum GH level was 38.4 ng/mL, and failure of GH suppression was noted during an oral glucose tolerance test (OGTT; nadir serum GH, 22.7 ng/mL). Magnetic resonance imaging (MRI) of the brain revealed a 12-mm-sized pituitary adenoma. Transsphenoidal surgery was performed and a pituitary adenoma displaying positive immunohistochemical staining for GH was reported. Pituitary MRI scan was performed 4 months after surgery and showed recurrence/residual tumor. Medical treatment with a long-acting somatostatin analogue for six months was unsuccessful. As a result, secondary surgery was performed. Three months after reoperation, the GH level was 0.2 ng/mL and insulin-like growth factor 1 was 205 ng/mL. Case two involved a 14.9-year-old boy, who was referred to our department for his tall stature. His basal GH level was 9.3 ng/mL, and failure of GH suppression was reported during OGTT (nadir GH, 9.0 ng/mL). Pituitary MRI showed a 6-mm-sized pituitary adenoma. Surgery was done and histopathological examination demonstrated a pituitary adenoma with positive staining for GH. Three months after surgery, the GH level was 0.2 ng/mL and nadir GH during OGTT was less than 0.1 ng/mL. Pituitary MRI scans showed no residual tumor. We present two cases of gigantism caused by a GH-secreting pituitary adenoma with clinical and microscopic findings.

  4. Gigantism caused by growth hormone secreting pituitary adenoma

    Directory of Open Access Journals (Sweden)

    Noorisaem Rhee

    2014-06-01

    Full Text Available Gigantism indicates excessive secretion of growth hormones (GH during childhood when open epiphyseal growth plates allow for excessive linear growth. Case one involved a 14.7-year-old boy presented with extreme tall stature. His random serum GH level was 38.4 ng/mL, and failure of GH suppression was noted during an oral glucose tolerance test (OGTT; nadir serum GH, 22.7 ng/mL. Magnetic resonance imaging (MRI of the brain revealed a 12-mm-sized pituitary adenoma. Transsphenoidal surgery was performed and a pituitary adenoma displaying positive immunohistochemical staining for GH was reported. Pituitary MRI scan was performed 4 months after surgery and showed recurrence/residual tumor. Medical treatment with a long-acting somatostatin analogue for six months was unsuccessful. As a result, secondary surgery was performed. Three months after reoperation, the GH level was 0.2 ng/mL and insulin-like growth factor 1 was 205 ng/mL. Case two involved a 14.9-year-old boy, who was referred to our department for his tall stature. His basal GH level was 9.3 ng/mL, and failure of GH suppression was reported during OGTT (nadir GH, 9.0 ng/mL. Pituitary MRI showed a 6-mm-sized pituitary adenoma. Surgery was done and histopathological examination demonstrated a pituitary adenoma with positive staining for GH. Three months after surgery, the GH level was 0.2 ng/mL and nadir GH during OGTT was less than 0.1 ng/mL. Pituitary MRI scans showed no residual tumor. We present two cases of gigantism caused by a GH-secreting pituitary adenoma with clinical and microscopic findings.

  5. High-detail snapshots of rare gigantic jet lightning

    Science.gov (United States)

    Schultz, Colin

    2011-08-01

    In the ionosphere, more than 80 kilometers above Earth's surface, incoming radiation reacts with the thin air to produce highly charged ions, inducing an electric potential between the ionosphere and the surface. This charge difference is dissipated by a slow leak from the ionosphere during calm weather and reinvigorated by a charge built up near the surface during a thunderstorm. In 2001, however, researchers discovered gigantic jets (GJs), powerful lightning that arcs from tropospheric clouds up to the ionosphere, suggesting there may be an alternate path by which charge is redistributed. GJs are transient species, and little is known about how much charge they can carry, how they form, or how common they are. In a step toward answering these questions, Lu et al. report on two GJs that occurred near very high frequency (VHF) lightning detection systems, which track the development of lightning in three spatial dimensions, giving an indication of the generation mechanism. The researchers also measured the charge transfer in the two GJs through remote sensing of magnetic fields. They found that both jets originated from the development of otherwise normal intracloud lightning. The dissipation of the cloud's positively charged upper layer allowed the negative lightning channel to break through and travel up out of the top of the cloud to the ionosphere. The first jet, which occurred off the coast of Florida, leapt up to 80 kilometers, depositing 110 coulombs of negative charge in 370 milliseconds. The second jet, observed in Oklahoma, traveled up to 90 kilometers, raising only 10-20 coulombs in 300 milliseconds. Each new observation of gigantic jets such as these can provide valuable information toward understanding this novel atmospheric behavior. (Geophysical Research Letters, doi:10.1029/2011GL047662, 2011)

  6. Gigantism caused by growth hormone secreting pituitary adenoma

    Science.gov (United States)

    Rhee, Noorisaem; Jeong, Kumi; Yang, Eun Mi

    2014-01-01

    Gigantism indicates excessive secretion of growth hormones (GH) during childhood when open epiphyseal growth plates allow for excessive linear growth. Case one involved a 14.7-year-old boy presented with extreme tall stature. His random serum GH level was 38.4 ng/mL, and failure of GH suppression was noted during an oral glucose tolerance test (OGTT; nadir serum GH, 22.7 ng/mL). Magnetic resonance imaging (MRI) of the brain revealed a 12-mm-sized pituitary adenoma. Transsphenoidal surgery was performed and a pituitary adenoma displaying positive immunohistochemical staining for GH was reported. Pituitary MRI scan was performed 4 months after surgery and showed recurrence/residual tumor. Medical treatment with a long-acting somatostatin analogue for six months was unsuccessful. As a result, secondary surgery was performed. Three months after reoperation, the GH level was 0.2 ng/mL and insulin-like growth factor 1 was 205 ng/mL. Case two involved a 14.9-year-old boy, who was referred to our department for his tall stature. His basal GH level was 9.3 ng/mL, and failure of GH suppression was reported during OGTT (nadir GH, 9.0 ng/mL). Pituitary MRI showed a 6-mm-sized pituitary adenoma. Surgery was done and histopathological examination demonstrated a pituitary adenoma with positive staining for GH. Three months after surgery, the GH level was 0.2 ng/mL and nadir GH during OGTT was less than 0.1 ng/mL. Pituitary MRI scans showed no residual tumor. We present two cases of gigantism caused by a GH-secreting pituitary adenoma with clinical and microscopic findings. PMID:25077093

  7. Thyasirid bivalves from Cretaceous and Paleogene cold seeps

    Directory of Open Access Journals (Sweden)

    Krzysztof Hryniewicz

    2017-11-01

    Full Text Available We present a systematic study of thyasirid bivalves from Cretaceous to Oligocene seep carbonates worldwide. Eleven species of thyasirid bivalves are identified belonging to three genera: Conchocele, Maorithyas, and Thyasira. Two species are new: Maorithyas humptulipsensis sp. nov. from middle Eocene seep carbonates in the Humptulips Formation, Washington State, USA, and Conchocele kiritachiensis sp. nov. from the late Eocene seep deposit at Kiritachi, Hokkaido, Japan. Two new combinations are provided: Conchocele townsendi (White, 1890 from Maastrichtian strata of the James Ross Basin, Antarctica, and Maorithyas folgeri (Wagner and Schilling, 1923 from Oligocene rocks from California, USA. Three species are left in open nomenclature. We show that thyasirids have Mesozoic origins and appear at seeps before appearing in “normal” marine environments. These data are interpreted as a record of seep origination of thyasirids, and their subsequent dispersal to non-seep environments. We discuss the age of origination of thyasirids in the context of the origin of the modern deep sea fauna and conclude that thyasirids could have deep sea origins. This hypothesis is supported by the observed lack of influence of the Cretaceous and Paleogene Oceanic Anoxic Events on the main evolutionary lineages of the thyasirids, as seen in several other members of the deep sea fauna.

  8. The miRNA biogenesis in marine bivalves

    Directory of Open Access Journals (Sweden)

    Umberto Rosani

    2016-03-01

    Full Text Available Small non-coding RNAs include powerful regulators of gene expression, transposon mobility and virus activity. Among the various categories, mature microRNAs (miRNAs guide the translational repression and decay of several targeted mRNAs. The biogenesis of miRNAs depends on few gene products, essentially conserved from basal to higher metazoans, whose protein domains allow specific interactions with dsRNA. Here, we report the identification of key genes responsible of the miRNA biogenesis in 32 bivalves, with particular attention to the aquaculture species Mytilus galloprovincialis and Crassostrea gigas. In detail, we have identified and phylogenetically compared eight evolutionary conserved proteins: DROSHA, DGCR8, EXP5, RAN, DICER TARBP2, AGO and PIWI. In mussels, we recognized several other proteins participating in the miRNA biogenesis or in the subsequent RNA silencing. According to digital expression analysis, these genes display low and not inducible expression levels in adult mussels and oysters whereas they are considerably expressed during development. As miRNAs play an important role also in the antiviral responses, knowledge on their production and regulative effects can shed light on essential molecular processes and provide new hints for disease prevention in bivalves.

  9. Marine Bivalve Cellular Responses to Beta Blocker Exposures ...

    Science.gov (United States)

    β blockers are prescription drugs used for medical treatment of hypertension and arrhythmias. They prevent binding of agonists such as catecholamines to β adrenoceptors. In the absence of agonist induced activation of the receptor, adenylate cyclase is not activated which in turn limits cAMP production and protein kinase A activation, preventing increases in blood pressure and arrhythmias. After being taken therapeutically, commonly prescribed β blockers may make their way to coastal habitats via discharge from waste water treatment plants (WWTP) posing a potential risk to aquatic organisms. The aim of our research is to evaluate cellular responses of three commercially important marine bivalves - Eastern oysters, blue mussels and hard clams - upon exposure to two β blocker drugs, propranolol and metoprolol, and to find molecular initiating events (MIEs) indicative of the exposure. Bivalves were obtained from Narragansett Bay (Rhode Island, USA) and acclimated in the laboratory. Following acclimation, gills and hepatopancreas (HP) tissues were harvested and separately exposed to 0, 1, 10, 100 and 1000 ng/l of each drug. Tissues were bathed in 30 parts per thousand (ppt) filtered seawater, antibiotic mix, Leibovitz nutrient media, and the test drug. Exposures were conducted for 24 hours and samples were saved for cellular biomarker assays. A lysosomal destabilization assay, which is a marker of membrane damage, was also performed at the end of each exposure.

  10. Spermatozoan ultrastructure in the trigonioid bivalve Neotrigonia margaritacea Lamarck (Mollusca): Comparison with other bivalves, especially Trigonioida and Unionoida

    Science.gov (United States)

    Healy, J. M.

    1996-06-01

    Spermatozoa of the trigonioid bivalve Neotrigonia margaritacea (Lamarck) (Trigoniidae, Trigonioida) are examined ultrastructurally. A cluster of discoidal, proacrosomal vesicles (between 9 to 15 in number) constitutes the acrosomal complex at the nuclear apex. The nucleus is short (2.4 2.6 μm long, maximum diameter 2.2 μm), blunt-conical in shape, and exhibits irregular lacunae within its contents. Five or sometimes four round mitochondria are impressed into shallow depressions in the base of the nucleus as is a discrete centriolar fossa. The mitochondria surround two orthogonally arranged centrioles to form, collectively, the midpiece region. The distal centriole, anchored by nine satellite fibres to the plasma membrane, acts as a basal body to the sperm flagellum. The presence of numerous proacrosomal vesicles instead of a single, conical acrosomal vesicle sets Neotrigonia (and the Trigonioida) apart from other bivalves, with the exception of the Unionoida which are also known to exhibit this multivesicular condition. Spermatozoa of N. margaritacea are very similar to those of the related species Neotrigonia bednalli (Verco) with the exception that the proacrosomal vesicles of N. margaritacea are noticeably larger than those of N. bednalli.

  11. Optimal designs of mollusk shells from bivalves to snails.

    Science.gov (United States)

    Okabe, Takuya; Yoshimura, Jin

    2017-02-10

    Bivalve, ammonite and snail shells are described by a small number of geometrical parameters. Raup noted that the vast majority of theoretically possible shell forms do not occur in nature. The constraint factors that regulate the biased distribution of natural form have long since been an open problem in evolution. The problem of whether natural shell form is a result of optimization remains unsolved despite previous attempts. Here we solve this problem by considering the scaling exponent of shell thickness as a morphological parameter. The scaling exponent has a drastic effect on the optimal design of shell shapes. The observed characteristic shapes of natural shells are explained in a unified manner as a result of optimal utilization of shell material resources, while isometric growth in thickness leads to impossibly tight coiling.

  12. Reproductive investment in the intertidal bivalve Macoma balthica

    Science.gov (United States)

    Honkoop, P. J. C.; Van der Meer, J.; Beukema, J. J.; Kwast, D.

    1999-05-01

    Bivalve eggs generally contain large amounts of lipids which, in comparison with proteins and carbohydrates, have high energy contents and are thus costly in energetic terms. As lipid contents vary between species, comparisons of reproductive investments should not only include numbers and sizes of eggs, but also their energy content. We estimated the investment in egg material of mature females of the Baltic tellin Macoma balthica (L.) in terms of both mass and energy content. All mass below a minimum body mass (below which no eggs are produced) was defined as structural mass. This threshold amounts to a body mass index (BMI) of 5.6 (ash-free dry mass per cubic shell length in mg cm -3). More than half (55%) of the mass above the structural mass was invested in egg material and 45% in extra somatic tissue and tissue for production and storage of gametes. This means that the amount of eggs spawned ranged from 0 (at BMI = 5.6 mg cm -3) to 33% of the total ash-free dry mass (at a high BMI value of 14 mg cm -3). Eggs contained a relatively large amount of lipids, about 30% of their ash-free dry mass, whereas non-egg material contained only about 7% lipids. Eggs of two other bivalves in the Wadden Sea, the cockle Cerastoderma edule and the mussel Mytilus edulis, were smaller and contained only about 11% and 20% lipids, respectively. Energy content of M. balthica eggs amounted to ˜0.006 J, in the other two species to ˜0.002 J. The function of the more expensive eggs in M. balthica may be related to its early spawning in spring, causing slower larval development until first feeding.

  13. Management of pituitary gigantism. The role of bromocriptine and radiotherapy.

    Science.gov (United States)

    Ritzén, E M; Wettrell, G; Davies, G; Grant, D B

    1985-09-01

    True gigantism with overproduction of growth hormone (GH) and prolactin (PRL) was diagnosed in two boys, aged 13 years (case I) and 7 1/2 years (case II). Both had shown increased growth rates since early childhood (from 4 years and 1 1/2 years, respectively), but no skeletal acromegalic features were noted. However, both showed increased sweating and both had advanced pubic hair relative to testis volume. No other pituitary dysfunction was recorded. Case I underwent transsphenoidal surgery with only incomplete and temporary suppression of GH and PRL levels. However, in both patients bromocriptine administration promptly suppressed PRL levels. Following combined irradiation and bromocriptine treatment, GH also gradually normalized over a period of 2 years. Both boys are still on treatment, and both showed an increase in plasma GH concentrations when the dose of bromocriptine was reduced or discontinued, indicating that even 3 1/2-5 years after irradiation therapy (and during continuous treatment with bromocriptine) the disease was controlled but not cured. However, in these two boys bromocriptine has proved effective in controlling the PRL/GH oversecretion.

  14. The clinical presentation and biochemical diagnosis of acromegaly and gigantism.

    Science.gov (United States)

    Jialal, I; Nathoo, B C; Joubert, S; Asmal, A C; Pillay, N L

    1982-04-24

    Over a 5-year period 14 patients with acromegaly and gigantism were seen at the endocrine clinic of King Edward VIII Hospital: 9 were Blacks and 5 Indians; 8 of the patients were women. The mean age of the patients was 46 years. Surprisingly, only 2 patients complained of acral overgrowth. Symptomatology was varied and not characteristic of the condition. On examination all patients had unequivocal signs of soft-tissue and bony overgrowth, 64% had visual abnormalities and 50% hypertension. Radiologically, 88% showed an enlarged pituitary fossa. On biochemical investigation, the fasting levels of growth hormone (GH) were increased in 12 patients and during oral glucose tolerance tests, the GH levels in these 12 patients were not suppressed. One patient in whom the fasting GH level was not increased had progressed to the stage of panhypopituitarism, in the remaining patient challenge with thyrotrophin-releasing hormone (TRH) led to increased GH levels and L-dopa challenge resulted in a paradoxical decrease in GH levels. Seven patients with increased GH levels who were challenged with L-dopa showed the typical decrease in GH levels found in this condition; in 5 of these patients, challenged with TRH, GH levels increased. The findings emphasize that despite the ease of clinical diagnosis, appropriate biochemical investigations are necessary to confirm the exact status of the disease, which is rare in the population studied.

  15. Pituitary tumour causing gigantism. Morphology and in vitro hormone secretion.

    Science.gov (United States)

    Anniko, M; Ritzén, E M

    1986-01-01

    True gigantism with overproduction of growth hormone (GH) and prolactin (PRL) was diagnosed in a 13-year-old boy. The clinical history indicated that the tumour had caused an oversecretion of GH since the age of 4-5 years. At diagnosis, the sella turcica was markedly enlarged. No infiltrative growth was noted at surgery. Endocrine investigations showed elevated GH and PRL secretion. Light and electron microscopy of tumour tissue revealed densely packed pleomorphic cells of both GH and PRL type. In addition, oncocyte-like cells were observed. Organ culture of pieces of tumour tissue demonstrated continued secretion of GH and PRL into the medium for more than 5 days in vitro. Addition of bromocriptine to the medium caused a rapid decline in PRL secretion while GH secretion remained the same. X-ray irradiation in vitro also caused a decrease in PRL secretion. These effects of bromocriptine and X-ray on hormone secretion in vitro mirrored the corresponding effect of treatment, when the patient showed signs of tumour recurrence after pituitary surgery. It is concluded that also in childhood, the in vitro response of tumour tissue to various treatments may be explored as a possible way to predict the efficacy of pharmacological or irradiation treatment of pituitary tumours.

  16. Controlled Growth of Gigantic Swirls in a Laboratory Magnetosphere

    Science.gov (United States)

    Worstell, M. W.; Mauel, M. E.; Roberts, T. M.

    2012-10-01

    Space and laboratory plasma confined by a strong magnetic field have remarkable properties. Low frequency mixing of the plasma occurs through the interchange of long plasma-filled tubes aligned with the magnetic field. The plasma dynamics becomes two-dimensional because these tubes can only move radially or circulate around the poles of the magnetic dipole. Studies of turbulent interchange dynamics made using the Collisionless Terella Experiment (CTX) show that turbulence appears as chaotic time-varying modes with broad global mode structures that interact nonlinearly and form an inverse cascade.footnotetextB.A. Grierson, M.W. Worstell, M.E. Mauel, Phys. Plasmas 16 055902 (2009) When we drive vortex mixing through the application of electrostatic bias to multiple probes, we break the rotational symmetry of the plasma and small vortex tubes are seen to drive larger ``gigantic'' swirls. Statistical analysis of the time-evolving spectra and measurement of the bicoherence of the turbulence show an increase of three wave coupling during non-axisymmetric electrostatic drive of the probe array.

  17. Characteristics and generation of secondary jets and secondary gigantic jets

    Science.gov (United States)

    Lee, Li-Jou; Huang, Sung-Ming; Chou, Jung-Kung; Kuo, Cheng-Ling; Chen, Alfred B.; Su, Han-Tzong; Hsu, Rue-Rou; Frey, Harald U.; Takahashi, Yukihiro; Lee, Lou-Chuang

    2012-06-01

    Secondary transient luminous events (TLEs) recorded by the ISUAL-FORMOSAT2 mission can either be secondary jets or secondary gigantic jets (GJs), depending on their terminal altitudes. The secondary jets emerge from the cloud top beneath the preceding sprites and extend upward to the base of the sprites at ˜50 km. The secondary jets likely are negative electric discharges with vertically straight luminous columns, morphologically resembling the trailing jet of the type-I GJs. The number of luminous columns in a secondary jet seems to be affected by the size of the effective capacitor plate formed near the base of the preceding sprites and the charge distribution left behind by the sprite-inducing positive cloud-to-ground discharges. The secondary GJs originate from the cloud top under the shielding area of the preceding sprites, and develop upward to reach the lower ionosphere at ˜90 km. The observed morphology of the secondary GJs can either be the curvy shifted secondary GJs extending outside the region occupied by the preceding sprites or the straight pop-through secondary GJs developing through the center of the preceding circular sprites. A key factor in determining the terminal height of the secondary TLEs appears to be the local ionosphere boundary height that established by the preceding sprites. The abundance and the distribution of the negative charge in the thundercloud following the sprite-inducing positive cloud-to-ground discharges may play important role in the generation of the secondary TLEs.

  18. Comparative in vitro study on free radical scavenging potential of selected bivalve species

    Digital Repository Service at National Institute of Oceanography (India)

    Shenai-Tirodkar, P.S.; Pawar, R.T.; Jagtap, T.G.

    Bivalves such as, Crassostrea spp., Meretrix casta, Placuna placenta and Polymesoda erosa are largely consumed as edible seafood. It forms natural source of nutrition in coastal and worldwide population. Free radical scavenging activities...

  19. Distribution of organotin compounds in the bivalves of the Aegean Sea, Greece

    NARCIS (Netherlands)

    Chandrinou, S.; Pappas, K.; Nikolaou, A.; Stasinakis, A.S.; Wegener, J.W.M.; Alexandropoulos, Th.; Thomaidis, N.S.

    2007-01-01

    Five bivalve species - Mytilus galloprovinciallis (Mediterranean mussels), Venus gallina (stripped venus), Modiola barbatus L. (bearded horse mussels), Pecten jacobeus (scallops) and Callista chione (hard clams) - were collected from seven areas in Aegean Sea, Greece, between August 2001 and January

  20. Bioaccumulation of 210Po in common gastropod and bivalve species from the northern Gulf.

    Science.gov (United States)

    Uddin, S; Bebhehani, M

    2014-06-01

    This study sets the baseline for the concentration of the natural-series radionuclide polonium-210 in two species of gastropods and four species of bivalves that are common to the Northern Arabian/Persian Gulf. (210)Po is primarily absorbed from water and via ingestion of detrital material by gastropoda and bivalves. This concentrated (210)Po can then be passed along to the next trophic level of the marine food web. The lowest (210)Po concentration was measured in the gastropod Stomatella auricular (10.36-12.39Bq kg(-1)dry) and the highest in the bivalve Marica marmorata (193.51-215.60Bq kg(-1)dry). The measured concentration factor for these molluscs in the northern Gulf varied between 4.8 and 115×10(3), values very similar to the IAEA recommended value for bivalves and gastropods of 2×10(4). Copyright © 2014 Elsevier Inc. All rights reserved.

  1. High pressure processing of bivalve shellfish and HPP's potential use as a virus intervention

    Science.gov (United States)

    Bivalve shellfish readily bioconcentrate pathogenic microbes and substance, such as algal and dinoflagulate toxins, fecal viruses and bacteria, and naturally present vibrio bacteria. High pressure processing (HPP) is currently used as an intervention for Vibrio vulnificus bacteria within molluscan ...

  2. The isotopic biosignatures of photo- vs. thiotrophic bivalves: are they preserved in fossil shells?

    Science.gov (United States)

    Dreier, A; Loh, W; Blumenberg, M; Thiel, V; Hause-Reitner, D; Hoppert, M

    2014-09-01

    Symbiont-bearing and non-symbiotic marine bivalves were used as model organisms to establish biosignatures for the detection of distinctive symbioses in ancient bivalves. For this purpose, the isotopic composition of lipids (δ13C) and bulk organic shell matrix (δ13C, δ34S, δ15N) from shells of several thiotrophic, phototrophic, or non-symbiotic bivalves were compared (phototrophic: Fragum fragum, Fragum unedo, Tridacna maxima; thiotrophic: Codakia tigerina, Fimbria fimbriata, Anodontia sp.; non-symbiotic: Tapes dorsatus, Vasticardium vertebratum, Scutarcopagia sp.). ∆13C values of bulk organic shell matrices, most likely representing mainly original shell protein/chitin biomass, were depleted in thio- and phototrophic bivalves compared to non-symbiotic bivalves. As the bulk organic shell matrix also showed a major depletion of δ15N (down to -2.2 ‰) for thiotrophic bivalves, combined δ13C and δ15N values are useful to differentiate between thio-, phototrophic, and non-symbiotic lifestyles. However, the use of these isotopic signatures for the study of ancient bivalves is limited by the preservation of the bulk organic shell matrix in fossils. Substantial alteration was clearly shown by detailed microscopic analyses of fossil (late Pleistocene) T. maxima and Trachycardium lacunosum shell, demonstrating a severe loss of quantity and quality of bulk organic shell matrix with time. Likewise, the composition and δ13C-values of lipids from empty shells indicated that a large part of these compounds derived from prokaryotic decomposers. The use of lipids from ancient shells for the reconstruction of the bivalve's life style therefore appears to be restricted. © 2014 John Wiley & Sons Ltd.

  3. Histological techniques for marine bivalve mollusks and crustaceans, 2nd edition

    OpenAIRE

    Howard, Dorothy W.; Lewis, Earl J.; Keller, B. Jane; Smith, Cecelia S.

    2004-01-01

    Investigators at the Cooperative Oxford Laboratory (COL) diagnose and study crustaceans, mollusks, finfish, and a variety of other marine and estuarine invertebrates to assess animal health. This edition updates the Histological Techniques for Marine Bivalve Mollusks manual by Howard and Smith (1983) with additional chapters on molluscan and crustacean techniques. The new edition is intended to serve as a guide for histological processing of shellfish, principally bivalve mollusks and crustac...

  4. Mercury accumulation in marine bivalves: Influences of biodynamics and feeding niche

    Energy Technology Data Exchange (ETDEWEB)

    Pan Ke [Division of Life Science, Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon (Hong Kong); Wang Wenxiong, E-mail: wwang@ust.hk [Division of Life Science, Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon (Hong Kong)

    2011-10-15

    Differences in the accumulation of mercury (Hg) in five species of marine bivalves, including scallops Chlamys nobilis, clams Ruditapes philippinarum, oysters Saccostrea cucullata, green mussels Perna viridis, and black mussels Septifer virgatus, were investigated. The bivalves displayed different patterns of Hg accumulation in terms of the body concentrations of methylmercury (MeHg) and total Hg (THg), as well as the ratio of MeHg to THg. Parameters of the biodynamics of the accumulation of Hg(II) and MeHg could reflect the species-dependent Hg concentrations in the bivalves. With the exception of black mussels, we found a significant relationship between the efflux rates of Hg(II) and the THg concentrations in the bivalves. The interspecific variations in the MeHg to THg ratio were largely controlled by the relative difference between the elimination rates of Hg(II) and MeHg. Stable isotope ({delta}{sup 13}C) analysis indicated that the five bivalve species had contrasting feeding niches, which may also affect the Hg accumulation. - Highlights: > Significant difference in Hg accumulation and MeHg:THg ratio in different bivalves. > THg concentrations in the bivalves were generally related to the efflux rates of Hg(II). > Elimination of Hg(II) and MeHg controlled the interspecific variation in MeHg:THg ratio. > MeHg and THg concentrations reflect the interaction of Hg biodynamics and food. - The species-specific body concentrations of MeHg and THg in bivalves reflect the complicated interaction between the biodynamics of Hg(II) and MeHg and the different food sources.

  5. Why might they be giants? Towards an understanding of polar gigantism.

    Science.gov (United States)

    Moran, Amy L; Woods, H Arthur

    2012-06-15

    Beginning with the earliest expeditions to the poles, over 100 years ago, scientists have compiled an impressive list of polar taxa whose body sizes are unusually large. This phenomenon has become known as 'polar gigantism'. In the intervening years, biologists have proposed a multitude of hypotheses to explain polar gigantism. These hypotheses run the gamut from invoking release from physical and physiological constraints, to systematic changes in developmental trajectories, to community-level outcomes of broader ecological and evolutionary processes. Here we review polar gigantism and emphasize two main problems. The first is to determine the true strength and generality of this pattern: how prevalent is polar gigantism across taxonomic units? Despite many published descriptions of polar giants, we still have a poor grasp of whether these species are unusual outliers or represent more systematic shifts in distributions of body size. Indeed, current data indicate that some groups show gigantism at the poles whereas others show nanism. The second problem is to identify underlying mechanisms or processes that could drive taxa, or even just allow them, to evolve especially large body size. The contenders are diverse and no clear winner has yet emerged. Distinguishing among the contenders will require better sampling of taxa in both temperate and polar waters and sustained efforts by comparative physiologists and evolutionary ecologists in a strongly comparative framework.

  6. Nursery function of coastal temperate benthic habitats: New insight from the bivalve recruitment perspective

    Science.gov (United States)

    Barbier, Pierrick; Meziane, Tarik; Forêt, Martin; Tremblay, Réjean; Robert, René; Olivier, Frédéric

    2017-03-01

    Marine habitat function has been typically investigated in terms of biogeochemical regulation but rarely in terms of population renewal, which is mainly controlled by recruitment dynamics. The recruitment phase is crucial for organisms with a bentho-pelagic life cycle, such as bivalves, and it regulates the population renewal success. This study provides new insight on the role of temperate benthic habitats on bivalve recruitment, as a function of nursery areas. Six dominant benthic habitats of the Chausey archipelago (Normandy, France) were studied. In each habitat, bivalve recruit assemblages were described at the end of two reproductive seasons. Furthermore, Ostrea edulis juveniles were immerged on each habitat during two months to compare growth performances and feeding status, estimated by fatty acid composition. Recruit assemblages differ from each habitat according to sediment grain-size composition and bathymetrical levels. Subtidal habitats, and especially Crepidula fornicata banks and Glycymeris glycymeris coarse sands, supported the highest species abundance and richness of recruits. All O. edulis juveniles fed on the same trophic resources but digestive glands of juveniles from C. fornicata banks were more concentrated in total fatty acids than those from subtidal G. glycymeris coarse sands and maerl banks. Our results depict the key role of subtidal and structured habitats, composed of ecosystem engineers, in enhancing bivalve recruitment and extending the bivalve population renewal. This study suggests that the crucial role of these habitats as bivalve nurseries must be integrated in management perspectives. 2-column fitting image. 1-column fitting image.

  7. An integrated ecosystem approach for assessing the potential role of cultivated bivalve shells as part of the carbon trading system

    DEFF Research Database (Denmark)

    Filgueira, Ramón; Byron, C.J.; Comeau, L.A.

    2015-01-01

    , is needed to provide a rigorous assessment of the role of bivalve mariculture in the CO2 cycle. On the other hand, the discussion about the inclusion of shells of cultured bivalves into the carbon trading system should be framed in the context of ecosystem goods and services. Humans culture bivalves......The role of bivalve mariculture in the CO2 cycle has been commonly evaluated as the balance between respiration, shell calcium carbonate sequestration and CO2 release during biogenic calcification. However, this approach neglects the ecosystem implications of cultivating bivalves at high densities...... with the aim of producing food, not sequestering CO2 in their shells, therefore the main ecosystem good provided by bivalve aquaculture is meat production, and shells should be considered as by-products of this human activity. This reasoning is key to split the CO2 released due to respiration between meat...

  8. Short-term fluctuations in bivalve larvae compared with some environmental factors in a coastal lagoon (South Portugal

    Directory of Open Access Journals (Sweden)

    Luis M.Z. Chícaro

    2000-12-01

    Full Text Available In this study, short-term fluctuations in bivalve larvae were compared with some triggering factors for a period of sixteen months. Data on the abundance of planktonic larvae, collected two to three times a week were related to water temperature, salinity, wind velocity, tidal amplitude and chlorophyll a. Higher densities of planktonic bivalve larvae were caught between May and August, but intense fluctuations in abundance were observed. Planktonic bivalve larvae of eighteen taxa were identified. Larvae of Mytilus galloprovincialis, Cerastoderma edule, Ruditapes decussates and Venerupis spp. were the most abundant. The seasonal fluctuations of bivalve abundance seem to be controlled by temperature, the major factor in the timing of the reproduction of bivalves. Nevertheless, advection may be also a key factor during the planktonic life of bivalve species in coastal systems, such as the Ria Formosa.

  9. Biology of the sauropod dinosaurs: the evolution of gigantism

    Science.gov (United States)

    Sander, P Martin; Christian, Andreas; Clauss, Marcus; Fechner, Regina; Gee, Carole T; Griebeler, Eva-Maria; Gunga, Hanns-Christian; Hummel, Jürgen; Mallison, Heinrich; Perry, Steven F; Preuschoft, Holger; Rauhut, Oliver W M; Remes, Kristian; Tütken, Thomas; Wings, Oliver; Witzel, Ulrich

    2011-01-01

    The herbivorous sauropod dinosaurs of the Jurassic and Cretaceous periods were the largest terrestrial animals ever, surpassing the largest herbivorous mammals by an order of magnitude in body mass. Several evolutionary lineages among Sauropoda produced giants with body masses in excess of 50 metric tonnes by conservative estimates. With body mass increase driven by the selective advantages of large body size, animal lineages will increase in body size until they reach the limit determined by the interplay of bauplan, biology, and resource availability. There is no evidence, however, that resource availability and global physicochemical parameters were different enough in the Mesozoic to have led to sauropod gigantism. We review the biology of sauropod dinosaurs in detail and posit that sauropod gigantism was made possible by a specific combination of plesiomorphic characters (phylogenetic heritage) and evolutionary innovations at different levels which triggered a remarkable evolutionary cascade. Of these key innovations, the most important probably was the very long neck, the most conspicuous feature of the sauropod bauplan. Compared to other herbivores, the long neck allowed more efficient food uptake than in other large herbivores by covering a much larger feeding envelope and making food accessible that was out of the reach of other herbivores. Sauropods thus must have been able to take up more energy from their environment than other herbivores. The long neck, in turn, could only evolve because of the small head and the extensive pneumatization of the sauropod axial skeleton, lightening the neck. The small head was possible because food was ingested without mastication. Both mastication and a gastric mill would have limited food uptake rate. Scaling relationships between gastrointestinal tract size and basal metabolic rate (BMR) suggest that sauropods compensated for the lack of particle reduction with long retention times, even at high uptake rates. The

  10. Biology of the sauropod dinosaurs: the evolution of gigantism.

    Science.gov (United States)

    Sander, P Martin; Christian, Andreas; Clauss, Marcus; Fechner, Regina; Gee, Carole T; Griebeler, Eva-Maria; Gunga, Hanns-Christian; Hummel, Jürgen; Mallison, Heinrich; Perry, Steven F; Preuschoft, Holger; Rauhut, Oliver W M; Remes, Kristian; Tütken, Thomas; Wings, Oliver; Witzel, Ulrich

    2011-02-01

    The herbivorous sauropod dinosaurs of the Jurassic and Cretaceous periods were the largest terrestrial animals ever, surpassing the largest herbivorous mammals by an order of magnitude in body mass. Several evolutionary lineages among Sauropoda produced giants with body masses in excess of 50 metric tonnes by conservative estimates. With body mass increase driven by the selective advantages of large body size, animal lineages will increase in body size until they reach the limit determined by the interplay of bauplan, biology, and resource availability. There is no evidence, however, that resource availability and global physicochemical parameters were different enough in the Mesozoic to have led to sauropod gigantism. We review the biology of sauropod dinosaurs in detail and posit that sauropod gigantism was made possible by a specific combination of plesiomorphic characters (phylogenetic heritage) and evolutionary innovations at different levels which triggered a remarkable evolutionary cascade. Of these key innovations, the most important probably was the very long neck, the most conspicuous feature of the sauropod bauplan. Compared to other herbivores, the long neck allowed more efficient food uptake than in other large herbivores by covering a much larger feeding envelope and making food accessible that was out of the reach of other herbivores. Sauropods thus must have been able to take up more energy from their environment than other herbivores. The long neck, in turn, could only evolve because of the small head and the extensive pneumatization of the sauropod axial skeleton, lightening the neck. The small head was possible because food was ingested without mastication. Both mastication and a gastric mill would have limited food uptake rate. Scaling relationships between gastrointestinal tract size and basal metabolic rate (BMR) suggest that sauropods compensated for the lack of particle reduction with long retention times, even at high uptake rates. The

  11. Cisto gigante de colédoco Giant choledochal cyst

    Directory of Open Access Journals (Sweden)

    Olival Cirilo Lucena da Fonseca-Neto

    2007-12-01

    Full Text Available INTRODUÇÃO: A doença cística das vias biliares é anomalia congênita que pode acometer as vias biliares intra e/ou extra-hepáticas. A extra-hepática inclui os cistos de colédoco e a intra-hepática é conhecida por Doença de Caroli. Os cistos de colédoco de tamanho gigante são muito raros. OBJETIVO: Relatar o caso de um cisto de colédoco de tamanho gigante em uma paciente feminina. RELATO DE CASO: Mulher de 19 anos foi admitida com história de icterícia e acolia fecal há sete dias. Referia dor epigástrica associada com ingestão de dieta rica em gordura. Nos antecedentes pessoais relatou dois episódios de icterícia, aos 8 e 14 anos, que progrediram espontaneamente. No exame físico apresentava icterícia (+3/+4 e uma massa palpável indolor em mesogástrio foram os únicos achados. A ultrassonografia demonstrou grande formação cística de paredes finas adjacente ao hepatocolédoco, pâncreas e rim direito que media 18,5 x 10,2 cm. A colangioressonância confirmou o grande cisto de colédoco e hepatojejunoanastomose em "Y" de Roux após excisão do cisto e colecistectomia foi realizada. A formação cística media 20 x 15,5 x 12,5 cm e com um volume médio de 1000 mL. A paciente encontra-se em acompanhamento ambulatorial sem alterações hepatobiliares após o sétimo mês da operação. CONCLUSÃO: O cisto de colédoco deve fazer parte do diagnóstico diferencial em pacientes adultos jovens com icterícia e massa palpável; no entanto, a diferenciação entre ele e neoplasia maligna deve ser pesquisada.BACKGROUND: Choledochal cyst represents a rare congenital anomaly, eventually associated with intra and extrahepatic biliary tract disorders. Extrahepatic diseases include choledochal cysts and congenital dilation of the lower intrahepatic bile duct is known as Caroli's disease. Giant choledochal cyst constitutes a very rare abnormality. AIM:To report a giant choledochal cyst in a female patient. CASE REPORT: A 19-year

  12. Aneurisma gigante parasselar simulando tumor de hipófise

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    Luiz Augusto Casulari Roxo da Motta

    1988-12-01

    Full Text Available Revisamos 7 pacientes com comprometimento da sela turca ao raio X do crânio que apresentavam aneurisma gigante da porção intracavernosa da artéria carótida (6 casos e aneurisma da artéria comunicante anterior (1 caso. As alterações encontradas foram: cefaléia (7/7, oftalmoplegia complexa interessando III, IV e VI nervos cranianos (5/7 e comprometimento do V nervo (4/7, dor ocular (4/7. Outras alterações encontradas foram: sinais meníngeos (2/7, cegueira unilateral (1/7, hemiparesia (1/7 cacosmia (1/7 e quadrantanopsia bitemporal inferior (1/7. Cinco pacientes com aneurisma da porção intracavernosa da artéria carótida beneficiaram-se com a ligadura progressiva da artéria carótida interna a nível cervical; o outro paciente faleceu antes da realização da operação. O paciente com aneurisma da artéria comunicante anterior foi submetido a clipagem do aneurisma, tendo boa evolução. Baseados neste estudo e em concordância com a literatura, concluímos que o diagnóstico diferencial entre aneurisma localizado na região parasselar e outras patologias dessa área freqüentemente apresenta dificuldade. O diagnóstico definitivo requer a realização de angiografia cerebral. O tratamento cirúrgico, por ligadura da carótida interna na região cervical, é benéfico e quase desprovido de complicações.

  13. Corticoides intralesionales en lesiones a células gigantes

    Directory of Open Access Journals (Sweden)

    J.P. Crestanello Nese

    2003-12-01

    Full Text Available Desde su descripción original, las lesiones de células gigantes (LCG han sido entidades controvertidas, desde el punto de vista de su origen, de su comportamiento clínico, de sus características radiográficas e histológicas, así como de su tratamiento. Para su tratamiento se han considerado alternativas quirúrgicas y no quirúrgicas. En este trabajo, se presentan tres nuevos casos de LCG, en los cuales se realizó infiltración intralesional con corticoides como una maniobra previa y complementaria a la quirúrgica. Luego de la infiltración, se observó una disminución del tamaño de las lesiones y un cambio en sus características macroscópicas, se trato por enucleación un caso y por remodelación quirúrgica los dos restantes.Giant cell lesions (GCL have been controversial entities since its original description. Its origin, clinical behavior, radiographic and histological features and also its treatment are polemical. The therapeutic possibilities are surgical or non surgical. In this paper, the intralesional infiltration with steroids is presented like a previous and complementary therapy to surgery alone. Three new cases of GCL are presented. All of them were first treated with intralesional infiltration with steroids. After that,a partial remission and a change of the macroscopic characteristics were observed and one of the lesion was then enucleated while for the others two surgical remodelation were necessary to do.

  14. Genomic gigantism: DNA loss is slow in mountain grasshoppers.

    Science.gov (United States)

    Bensasson, D; Petrov, D A; Zhang, D X; Hartl, D L; Hewitt, G M

    2001-02-01

    Several studies have shown DNA loss to be inversely correlated with genome size in animals. These studies include a comparison between Drosophila and the cricket, Laupala, but there has been no assessment of DNA loss in insects with very large genomes. Podisma pedestris, the brown mountain grasshopper, has a genome over 100 times as large as that of Drosophila and 10 times as large as that of Laupala. We used 58 paralogous nuclear pseudogenes of mitochondrial origin to study the characteristics of insertion, deletion, and point substitution in P. pedestris and Italopodisma. In animals, these pseudogenes are "dead on arrival"; they are abundant in many different eukaryotes, and their mitochondrial origin simplifies the identification of point substitutions accumulated in nuclear pseudogene lineages. There appears to be a mononucleotide repeat within the 643-bp pseudogene sequence studied that acts as a strong hot spot for insertions or deletions (indels). Because the data for other insect species did not contain such an unusual region, hot spots were excluded from species comparisons. The rate of DNA loss relative to point substitution appears to be considerably and significantly lower in the grasshoppers studied than in Drosophila or Laupala. This suggests that the inverse correlation between genome size and the rate of DNA loss can be extended to comparisons between insects with large or gigantic genomes (i.e., Laupala and Podisma). The low rate of DNA loss implies that in grasshoppers, the accumulation of point mutations is a more potent force for obscuring ancient pseudogenes than their loss through indel accumulation, whereas the reverse is true for Drosophila. The main factor contributing to the difference in the rates of DNA loss estimated for grasshoppers, crickets, and Drosophila appears to be deletion size. Large deletions are relatively rare in Podisma and Italopodisma.

  15. An evolutionary cascade model for sauropod dinosaur gigantism--overview, update and tests.

    Directory of Open Access Journals (Sweden)

    P Martin Sander

    Full Text Available Sauropod dinosaurs are a group of herbivorous dinosaurs which exceeded all other terrestrial vertebrates in mean and maximal body size. Sauropod dinosaurs were also the most successful and long-lived herbivorous tetrapod clade, but no abiological factors such as global environmental parameters conducive to their gigantism can be identified. These facts justify major efforts by evolutionary biologists and paleontologists to understand sauropods as living animals and to explain their evolutionary success and uniquely gigantic body size. Contributions to this research program have come from many fields and can be synthesized into a biological evolutionary cascade model of sauropod dinosaur gigantism (sauropod gigantism ECM. This review focuses on the sauropod gigantism ECM, providing an updated version based on the contributions to the PLoS ONE sauropod gigantism collection and on other very recent published evidence. The model consist of five separate evolutionary cascades ("Reproduction", "Feeding", "Head and neck", "Avian-style lung", and "Metabolism". Each cascade starts with observed or inferred basal traits that either may be plesiomorphic or derived at the level of Sauropoda. Each trait confers hypothetical selective advantages which permit the evolution of the next trait. Feedback loops in the ECM consist of selective advantages originating from traits higher in the cascades but affecting lower traits. All cascades end in the trait "Very high body mass". Each cascade is linked to at least one other cascade. Important plesiomorphic traits of sauropod dinosaurs that entered the model were ovipary as well as no mastication of food. Important evolutionary innovations (derived traits were an avian-style respiratory system and an elevated basal metabolic rate. Comparison with other tetrapod lineages identifies factors limiting body size.

  16. An Evolutionary Cascade Model for Sauropod Dinosaur Gigantism - Overview, Update and Tests

    Science.gov (United States)

    Sander, P. Martin

    2013-01-01

    Sauropod dinosaurs are a group of herbivorous dinosaurs which exceeded all other terrestrial vertebrates in mean and maximal body size. Sauropod dinosaurs were also the most successful and long-lived herbivorous tetrapod clade, but no abiological factors such as global environmental parameters conducive to their gigantism can be identified. These facts justify major efforts by evolutionary biologists and paleontologists to understand sauropods as living animals and to explain their evolutionary success and uniquely gigantic body size. Contributions to this research program have come from many fields and can be synthesized into a biological evolutionary cascade model of sauropod dinosaur gigantism (sauropod gigantism ECM). This review focuses on the sauropod gigantism ECM, providing an updated version based on the contributions to the PLoS ONE sauropod gigantism collection and on other very recent published evidence. The model consist of five separate evolutionary cascades (“Reproduction”, “Feeding”, “Head and neck”, “Avian-style lung”, and “Metabolism”). Each cascade starts with observed or inferred basal traits that either may be plesiomorphic or derived at the level of Sauropoda. Each trait confers hypothetical selective advantages which permit the evolution of the next trait. Feedback loops in the ECM consist of selective advantages originating from traits higher in the cascades but affecting lower traits. All cascades end in the trait “Very high body mass”. Each cascade is linked to at least one other cascade. Important plesiomorphic traits of sauropod dinosaurs that entered the model were ovipary as well as no mastication of food. Important evolutionary innovations (derived traits) were an avian-style respiratory system and an elevated basal metabolic rate. Comparison with other tetrapod lineages identifies factors limiting body size. PMID:24205267

  17. An evolutionary cascade model for sauropod dinosaur gigantism--overview, update and tests.

    Science.gov (United States)

    Sander, P Martin

    2013-01-01

    Sauropod dinosaurs are a group of herbivorous dinosaurs which exceeded all other terrestrial vertebrates in mean and maximal body size. Sauropod dinosaurs were also the most successful and long-lived herbivorous tetrapod clade, but no abiological factors such as global environmental parameters conducive to their gigantism can be identified. These facts justify major efforts by evolutionary biologists and paleontologists to understand sauropods as living animals and to explain their evolutionary success and uniquely gigantic body size. Contributions to this research program have come from many fields and can be synthesized into a biological evolutionary cascade model of sauropod dinosaur gigantism (sauropod gigantism ECM). This review focuses on the sauropod gigantism ECM, providing an updated version based on the contributions to the PLoS ONE sauropod gigantism collection and on other very recent published evidence. The model consist of five separate evolutionary cascades ("Reproduction", "Feeding", "Head and neck", "Avian-style lung", and "Metabolism"). Each cascade starts with observed or inferred basal traits that either may be plesiomorphic or derived at the level of Sauropoda. Each trait confers hypothetical selective advantages which permit the evolution of the next trait. Feedback loops in the ECM consist of selective advantages originating from traits higher in the cascades but affecting lower traits. All cascades end in the trait "Very high body mass". Each cascade is linked to at least one other cascade. Important plesiomorphic traits of sauropod dinosaurs that entered the model were ovipary as well as no mastication of food. Important evolutionary innovations (derived traits) were an avian-style respiratory system and an elevated basal metabolic rate. Comparison with other tetrapod lineages identifies factors limiting body size.

  18. Gigantism and acromegaly due to Xq26 microduplications and GPR101 mutation.

    Science.gov (United States)

    Trivellin, Giampaolo; Daly, Adrian F; Faucz, Fabio R; Yuan, Bo; Rostomyan, Liliya; Larco, Darwin O; Schernthaner-Reiter, Marie Helene; Szarek, Eva; Leal, Letícia F; Caberg, Jean-Hubert; Castermans, Emilie; Villa, Chiara; Dimopoulos, Aggeliki; Chittiboina, Prashant; Xekouki, Paraskevi; Shah, Nalini; Metzger, Daniel; Lysy, Philippe A; Ferrante, Emanuele; Strebkova, Natalia; Mazerkina, Nadia; Zatelli, Maria Chiara; Lodish, Maya; Horvath, Anelia; de Alexandre, Rodrigo Bertollo; Manning, Allison D; Levy, Isaac; Keil, Margaret F; Sierra, Maria de la Luz; Palmeira, Leonor; Coppieters, Wouter; Georges, Michel; Naves, Luciana A; Jamar, Mauricette; Bours, Vincent; Wu, T John; Choong, Catherine S; Bertherat, Jerome; Chanson, Philippe; Kamenický, Peter; Farrell, William E; Barlier, Anne; Quezado, Martha; Bjelobaba, Ivana; Stojilkovic, Stanko S; Wess, Jurgen; Costanzi, Stefano; Liu, Pengfei; Lupski, James R; Beckers, Albert; Stratakis, Constantine A

    2014-12-18

    Increased secretion of growth hormone leads to gigantism in children and acromegaly in adults; the genetic causes of gigantism and acromegaly are poorly understood. We performed clinical and genetic studies of samples obtained from 43 patients with gigantism and then sequenced an implicated gene in samples from 248 patients with acromegaly. We observed microduplication on chromosome Xq26.3 in samples from 13 patients with gigantism; of these samples, 4 were obtained from members of two unrelated kindreds, and 9 were from patients with sporadic cases. All the patients had disease onset during early childhood. Of the patients with gigantism who did not carry an Xq26.3 microduplication, none presented before the age of 5 years. Genomic characterization of the Xq26.3 region suggests that the microduplications are generated during chromosome replication and that they contain four protein-coding genes. Only one of these genes, GPR101, which encodes a G-protein-coupled receptor, was overexpressed in patients' pituitary lesions. We identified a recurrent GPR101 mutation (p.E308D) in 11 of 248 patients with acromegaly, with the mutation found mostly in tumors. When the mutation was transfected into rat GH3 cells, it led to increased release of growth hormone and proliferation of growth hormone-producing cells. We describe a pediatric disorder (which we have termed X-linked acrogigantism [X-LAG]) that is caused by an Xq26.3 genomic duplication and is characterized by early-onset gigantism resulting from an excess of growth hormone. Duplication of GPR101 probably causes X-LAG. We also found a recurrent mutation in GPR101 in some adults with acromegaly. (Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development and others.).

  19. Diversidad de sistemas planetarios sin gigantes gaseosos en discos de baja masa

    OpenAIRE

    Ronco, María Paula

    2013-01-01

    Como indica el título de esta tesis, el objetivo general de nuestro trabajo es poder analizar la diversidad de sistemas planetarios que podrían formarse alrededor de estrellas de tipo solar y sin gigantes gaseosos. Nuestro interés particular es estudiar estos sistemas en discos de baja masa, pues podemos asegurar que en ellos no hay posibilidad de formar planetas gigantes gaseosos. Para poder lograr este análisis desarrollamos simulaciones de N-cuerpos orientadas a estudiar el proceso de form...

  20. First evidence of immunomodulation in bivalves under seawater acidification and increased temperature.

    Directory of Open Access Journals (Sweden)

    Valerio Matozzo

    Full Text Available Water acidification, temperature increases and changes in seawater salinity are predicted to occur in the near future. In such a global climate change (GCC scenario, there is growing concern for the health status of both wild and farmed organisms. Bivalve molluscs, an important component of coastal marine ecosystems, are at risk. At the immunological level, the ability of an organism to maintain its immunosurveillance unaltered under adverse environmental conditions may enhance its survival capability. To our knowledge, only a few studies have investigated the effects of changing environmental parameters (as predicted in a GCC scenario on the immune responses of bivalves. In the present study, the effects of both decreased pH values and increased temperature on the important immune parameters of two bivalve species were evaluated for the first time. The clam Chamelea gallina and the mussel Mytilus galloprovincialis, widespread along the coast of the Northwestern Adriatic Sea, were chosen as model organisms. Bivalves were exposed for 7 days to three pH values (8.1, 7.7 and 7.4 at two temperatures (22 and 28°C. Three independent experiments were carried out at salinities of 28, 34 and 40 PSU. The total haemocyte count, Neutral Red uptake, haemolymph lysozyme activity and total protein levels were measured. The results obtained demonstrated that tested experimental conditions affected significantly most of the immune parameters measured in bivalves, even if the variation pattern of haemocyte responses was not always linear. Between the two species, C. gallina appeared more vulnerable to changing pH and temperature than M. galloprovincialis. Overall, this study demonstrated that climate changes can strongly affect haemocyte functionality in bivalves. However, further studies are needed to clarify better the mechanisms of action of changing environmental parameters, both individually and in combination, on bivalve haemocytes.

  1. Veda-scope: More comfortable than the bivalve speculum and cytologically equivalent.

    Science.gov (United States)

    Longmore, Peter G

    2004-04-01

    The aim of the present study was to confirm that the Veda-scope is equivalent to the bivalve speculum in the collection of endocervical cells, as confirmation of adequate cervical sampling for Pap smear testing. The study also aimed to assess the comfort level of the Veda-scope compared to the traditional bivalve speculum and the patient preference of the Veda-scope compared to the bivalve speculum. Multicentre, randomised, controlled crossover, cytologist blinded study. The total number of subjects enrolled in the study were 250. The number of evaluable subjects were 210. In primary efficacy analysis, no significant difference was seen between the presence or absence of endocervical cells in the smears using either the Veda-scope or the bivalve speculum. There was a high concordance level between the diagnosis assigned to each specimen of a paired sample, the diagnosis agreeing in 97.6% cases. The primary reason given by many women for avoidance of regular Pap smear examinations is the discomfort or pain experienced with sample collection with the bivalve speculum. In the present study, 92% of subjects indicated a preference for the Veda-scope for Pap smear collection, while only 8.4% preferred the bivalve speculum. Subject preference was also assessed with respect to how the subject rated the comfort level of her previous Pap smear. In subjects who rated their previous Pap smear as very comfortable or comfortable, 86% expressed a preference for the Veda-scope. This rose to 93% in subjects who rated their previous Pap smear as only tolerable. The results of the present study show that Pap smear collections with the Veda-scope are of equal quality to those collected with the bivalve speculum, with an equivalent diagnostic outcome. A very strong preference for the Veda-scope was shown by the women enrolled in the present study based on the comfort levels experienced with the two devices.

  2. Bio-accumulation kinetics of radioruthenium in marine bivalves. Laboratory study

    International Nuclear Information System (INIS)

    Mu, D.H.; Yan, S.P.; Gu, Y.J.; Li, D.J.; Du, J.Z.

    2007-01-01

    Three kinds of marine bivalves (wild Saccostrea cucullata, aquacultured Perna viridis and aquacultured Pinctada martens), collected from Daya Bay, the South China Sea, were used to investigate the bio-accumulation of radioruthenium in the glass aquarium with natural seawater (pH 8.20, 35 per mille salinity, filtered by 0.45 μm) at ambient temperature under laboratory feeding conditions. The experimental results show that the stead-state of biology concentration factor (BCF, ml/g) of radioruthenium was approached around 6 days for most species of bivalves. The values of BCF in shells are the highest in organs all the three bivalves. The orders of BCF values (ml x g -1 ) are as: Perna viridis (33.2) < Saccostrea cucullata (47.0) < Pinctada martensi (208.4) for shells and Saccostrea cucullata (1.5) < Pinctada martensi (2.2) ∼ Perma viridis (2.4) for soft tissues, respectively, after exposed for 14 days. The rate constants of uptake and elimination of radioruthenium on marine bivalves were also discussed by first-order kinetics model. The Pinctada martensi may be applicable to be an indictor for monitoring radioruthenium among the three bivalves. (author)

  3. Trace Fossil Evidence of Trematode-Bivalve Parasite-Host Interactions in Deep Time.

    Science.gov (United States)

    Huntley, John Warren; De Baets, Kenneth

    2015-01-01

    Parasitism is one of the most pervasive phenomena amongst modern eukaryotic life and yet, relative to other biotic interactions, almost nothing is known about its history in deep time. Digenean trematodes (Platyhelminthes) are complex life cycle parasites, which have practically no body fossil record, but induce the growth of characteristic malformations in the shells of their bivalve hosts. These malformations are readily preserved in the fossil record, but, until recently, have largely been overlooked by students of the fossil record. In this review, we present the various malformations induced by trematodes in bivalves, evaluate their distribution through deep time in the phylogenetic and ecological contexts of their bivalve hosts and explore how various taphonomic processes have likely biased our understanding of trematodes in deep time. Trematodes are known to negatively affect their bivalve hosts in a number of ways including castration, modifying growth rates, causing immobilization and, in some cases, altering host behaviour making the host more susceptible to their own predators. Digeneans are expected to be significant agents of natural selection. To that end, we discuss how bivalves may have adapted to their parasites via heterochrony and suggest a practical methodology for testing such hypotheses in deep time. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Environmental influence on population dynamics of the bivalve Anomalocardia brasiliana

    Science.gov (United States)

    Corte, Guilherme Nascimento; Coleman, Ross A.; Amaral, A. Cecília Z.

    2017-03-01

    Understanding how species respond to the environment in terms of population attributes (e.g. abundance, growth, mortality, fecundity, and productivity) is essential to protect ecologically and economically important species. Nevertheless, responses of macrobenthic populations to environmental features are overlooked due to the need of consecutive samplings and time-consuming measurements. We examined the population dynamics of the filter-feeding bivalve Anomalocardia brasiliana on a tidal flat over the course of one year to investigate the hypothesis that, as accepted for macrobenthic communities, populations inhabiting environments with low hydrodynamic conditions such as tidal flat should have higher attributes than populations inhabiting more energetic habitats (i.e. areas more influenced by wave energy such as reflective and intermediate beaches). This would be expected because the harsh conditions of more energetic habitats force organisms to divert more energy towards maintenance, resulting in lower population attributes. We found that A. brasiliana showed moderate growth and secondary production at the study area. Moreover the recruitment period was restricted to a few months. A comparison with previous studies showed that, contrary to expected, A. brasiliana populations from areas with low hydrodynamic conditions have lower abundance, growth, recruitment and turnover rate. It is likely that morphodynamic characteristics recorded in these environments, such as larger periods of air exposure and lower water circulation, may affect food conditions for filter-feeding species and increase competition. In addition, these characteristics may negatively affect macrobenthic species by enhancing eutrophication processes and anoxia. Overall, our results suggest that models accepted and applied at the macrobenthic community level might not be directly extended to A. brasiliana populations.

  5. The Perlman syndrome: familial renal dysplasia with Wilms tumor, fetal gigantism and multiple congenital anomalies.

    Science.gov (United States)

    Neri, G; Martini-Neri, M E; Katz, B E; Opitz, J M

    1984-09-01

    We describe a familial syndrome of renal dysplasia, Wilms tumor, hyperplasia of the endocrine pancreas, fetal gigantism, multiple congenital anomalies and mental retardation. This condition was previously described by Perlman et al [1973, 1975] and we propose to call it the "Perlman syndrome." It appears to be transmitted as an autosomal recessive trait. The possible relationships between dysplasia, neoplasia and malformation are discussed.

  6. Assessment of Unusual Gigantic Jets observed during the Monsoon season: First observations from Indian Subcontinent

    DEFF Research Database (Denmark)

    Singh, Rajesh; Maurya, Ajeet K.; Chanrion, Olivier

    2017-01-01

    observations. Here we report first observations of Gigantic Jets in Indian subcontinent over the Indo-Gangetic plains during the monsoon season. Two storms each produced two jets with characteristics not documented so far. Jets propagated similar to 37 km up remarkably in similar to 5 ms with velocity...

  7. Oxygen hypothesis of polar gigantism not supported by performance of Antarctic pycnogonids in hypoxia

    Science.gov (United States)

    Woods, H. Arthur; Moran, Amy L.; Arango, Claudia P.; Mullen, Lindy; Shields, Chris

    2008-01-01

    Compared to temperate and tropical relatives, some high-latitude marine species are large-bodied, a phenomenon known as polar gigantism. A leading hypothesis on the physiological basis of gigantism posits that, in polar water, high oxygen availability coupled to low metabolic rates relieves constraints on oxygen transport and allows the evolution of large body size. Here, we test the oxygen hypothesis using Antarctic pycnogonids, which have been evolving in very cold conditions (−1.8–0°C) for several million years and contain spectacular examples of gigantism. Pycnogonids from 12 species, spanning three orders of magnitude in body mass, were collected from McMurdo Sound, Antarctica. Individual sea spiders were forced into activity and their performance was measured at different experimental levels of dissolved oxygen (DO). The oxygen hypothesis predicts that, all else being equal, large pycnogonids should perform disproportionately poorly in hypoxia, an outcome that would appear as a statistically significant interaction between body size and oxygen level. In fact, although we found large effects of DO on performance, and substantial interspecific variability in oxygen sensitivity, there was no evidence for size×DO interactions. These data do not support the oxygen hypothesis of Antarctic pycnogonid gigantism and suggest that explanations must be sought in other ecological or evolutionary processes. PMID:19129117

  8. Un nuevo ejemplar de tortuga gigante del Mioceno de Arévalo (Ávila)

    OpenAIRE

    Jiménez Fuentes, Emiliano; Acosta, Pilar; Fincias San Martín, Benito

    1986-01-01

    RESUMEN: Se describe un nuevo ejemplar de tortuga gigante, encontrado en el Mioceno (Vallesiense-Inferior) de Arévalo (Ávila), clasificado como un macho adulto de Cheirogaster (s.l.) richardi (Bergounioux 1938; emend. Jiménez 1984).

  9. Treatment of pituitary gigantism with the growth hormone receptor antagonist pegvisomant.

    Science.gov (United States)

    Goldenberg, Naila; Racine, Michael S; Thomas, Pamela; Degnan, Bernard; Chandler, William; Barkan, Ariel

    2008-08-01

    Treatment of pituitary gigantism is complex and the results are usually unsatisfactory. The objective of the study was to describe the results of therapy of three children with pituitary gigantism by a GH receptor antagonist, pegvisomant. This was a descriptive case series of up to 3.5 yr duration. The study was conducted at a university hospital. Patients included three children (one female, two males) with pituitary gigantism whose GH hypersecretion was incompletely controlled by surgery, somatostatin analog, and dopamine agonist. The intervention was administration of pegvisomant. Plasma IGF-I and growth velocity were measured. In all three children, pegvisomant rapidly decreased plasma IGF-I concentrations. Growth velocity declined to subnormal or normal values. Statural growth fell into lower growth percentiles and acromegalic features resolved. Pituitary tumor size did not change in two children but increased in one boy despite concomitant therapy with a somatostatin analog. Pegvisomant may be an effective modality for the therapy of pituitary gigantism in children. Titration of the dose is necessary for optimal efficacy, and regular surveillance of tumor size is mandatory.

  10. Spontaneous remission of acromegaly or gigantism due to subclinical apoplexy of pituitary growth hormone adenoma.

    Science.gov (United States)

    Wang, Xian-Ling; Dou, Jing-Tao; Lü, Zhao-Hui; Zhong, Wen-Wen; Ba, Jian-Ming; Jin, Du; Lu, Ju-Ming; Pan, Chang-Yu; Mu, Yi-Ming

    2011-11-01

    Subclinical apoplexy of pituitary functional adenoma can cause spontaneous remission of hormone hypersecretion. The typical presence of pituitary growth hormone (GH) adenoma is gigantism and/or acromegaly. We investigated the clinical characteristics of patients with spontaneous partial remission of acromegaly or gigantism due to subclinical apoplexy of GH adenoma. Six patients with spontaneous remission of acromegaly or gigantism were enrolled. The clinical characteristics, endocrinological evaluation and imageological characteristics were retrospectively analyzed. In these cases, the initial clinical presences were diabetes mellitus or hypogonadism. No abrupt headache, vomiting, visual function impairment, or conscious disturbance had ever been complained of. The base levels of GH and insulin growth factor-1 (IGF-1) were normal or higher, but nadir GH levels were all still > 1 µg/L in 75 g oral glucose tolerance test. Magnetic resonance imaging detected enlarged sella, partial empty sella and compressed pituitary. The transsphenoidal surgery was performed in 2 cases, and the other patients were conservatively managed. All the patients were in clinical remission. When the clinical presences, endocrine evaluation, biochemical examination and imageology indicate spontaneous remission of GH hypersecretion in patients with gigantism or acromegaly, the diagnosis of subclinical apoplexy of pituitary GH adenoma should be presumed. To these patients, conservative therapy may be appropriate.

  11. Video, LMA and ULF observations of a negative gigantic jet in North Texas

    Science.gov (United States)

    Bruning, E. C.; Cummer, S.; Palivec, K.; Lyons, W. A.; Chmielewski, V.; MacGorman, D. R.

    2017-12-01

    On 8 September 2016 at 0125:38 UTC video of a negative gigantic jet was captured from Hawley, TX. VHF Lightning Mapping Arrays in West Texas and Oklahoma also observed the parent flash (duration of about 1 s) and, for the first time, mapped dozens of points along ascending negative leaders, lasting about 50 ms, which extended well above cloud top to about 35 km MSL altitude. A few well-located VHF sources were also detected near 50 km. Together, the video and VHF observations provide additional confirmation of the altitude at which the leader-to-streamer transition takes place in gigantic jet discharges. ULF magnetic field data from the Duke iCMC network show a current excursion associated with the onset of the upward movement of negative charge and leaders in the VHF. As the gigantic jet reached its full height, current spiked to 80 kA, followed by several hundred milliseconds of continuing current of 10-20 kA. Total charge moment change was about 6000 C km. The storm complex produced predominantly negative large charge moment change events, which is characteristic of storms that produce negative gigantic jets.

  12. Von recklinghausen neurofibromatosis-pachydermatocele causing lower limb gigantism: a case report.

    Science.gov (United States)

    Rekha, Arcot; Gopalan, T R

    2006-03-01

    Gigantism of the lower limb can occur because of plexiform neurofibromas. This condition is seen with café au lait patches and multiple neurofibromatosis in this case of von Recklinghausen neurofibromatosis. We report our patient and review literature of this uncommon condition.

  13. Increased Population Risk of AIP‐Related Acromegaly and Gigantism in Ireland

    Science.gov (United States)

    Radian, Serban; Diekmann, Yoan; Gabrovska, Plamena; Holland, Brendan; Bradley, Lisa; Wallace, Helen; Stals, Karen; Bussell, Anna‐Marie; McGurren, Karen; Cuesta, Martin; Ryan, Anthony W.; Herincs, Maria; Hernández‐Ramírez, Laura C.; Holland, Aidan; Samuels, Jade; Aflorei, Elena Daniela; Barry, Sayka; Dénes, Judit; Pernicova, Ida; Stiles, Craig E.; Trivellin, Giampaolo; McCloskey, Ronan; Ajzensztejn, Michal; Abid, Noina; Akker, Scott A.; Mercado, Moises; Cohen, Mark; Thakker, Rajesh V.; Baldeweg, Stephanie; Barkan, Ariel; Musat, Madalina; Levy, Miles; Orme, Stephen M.; Unterländer, Martina; Burger, Joachim; Kumar, Ajith V.; Ellard, Sian; McPartlin, Joseph; McManus, Ross; Linden, Gerard J.; Atkinson, Brew; Balding, David J.; Agha, Amar; Thompson, Chris J.; Hunter, Steven J.; Thomas, Mark G.; Morrison, Patrick J.

    2016-01-01

    ABSTRACT The aryl hydrocarbon receptor interacting protein (AIP) founder mutation R304* (or p.R304*; NM_003977.3:c.910C>T, p.Arg304Ter) identified in Northern Ireland (NI) predisposes to acromegaly/gigantism; its population health impact remains unexplored. We measured R304* carrier frequency in 936 Mid Ulster, 1,000 Greater Belfast (both in NI) and 2,094 Republic of Ireland (ROI) volunteers and in 116 NI or ROI acromegaly/gigantism patients. Carrier frequencies were 0.0064 in Mid Ulster (95%CI = 0.0027–0.013; P = 0.0005 vs. ROI), 0.001 in Greater Belfast (0.00011–0.0047) and zero in ROI (0–0.0014). R304* prevalence was elevated in acromegaly/gigantism patients in NI (11/87, 12.6%, P gigantism cases. tMRCA is consistent with historical/folklore accounts of Irish giants. Forward simulations predict many undetected carriers; geographically targeted population screening improves asymptomatic carrier identification, complementing clinical testing of patients/relatives. We generated disease awareness locally, necessary for early diagnosis and improved outcomes of AIP‐related disease. PMID:27650164

  14. Increased Population Risk of AIP-Related Acromegaly and Gigantism in Ireland.

    Science.gov (United States)

    Radian, Serban; Diekmann, Yoan; Gabrovska, Plamena; Holland, Brendan; Bradley, Lisa; Wallace, Helen; Stals, Karen; Bussell, Anna-Marie; McGurren, Karen; Cuesta, Martin; Ryan, Anthony W; Herincs, Maria; Hernández-Ramírez, Laura C; Holland, Aidan; Samuels, Jade; Aflorei, Elena Daniela; Barry, Sayka; Dénes, Judit; Pernicova, Ida; Stiles, Craig E; Trivellin, Giampaolo; McCloskey, Ronan; Ajzensztejn, Michal; Abid, Noina; Akker, Scott A; Mercado, Moises; Cohen, Mark; Thakker, Rajesh V; Baldeweg, Stephanie; Barkan, Ariel; Musat, Madalina; Levy, Miles; Orme, Stephen M; Unterländer, Martina; Burger, Joachim; Kumar, Ajith V; Ellard, Sian; McPartlin, Joseph; McManus, Ross; Linden, Gerard J; Atkinson, Brew; Balding, David J; Agha, Amar; Thompson, Chris J; Hunter, Steven J; Thomas, Mark G; Morrison, Patrick J; Korbonits, Márta

    2017-01-01

    The aryl hydrocarbon receptor interacting protein (AIP) founder mutation R304 * (or p.R304 * ; NM_003977.3:c.910C>T, p.Arg304Ter) identified in Northern Ireland (NI) predisposes to acromegaly/gigantism; its population health impact remains unexplored. We measured R304 * carrier frequency in 936 Mid Ulster, 1,000 Greater Belfast (both in NI) and 2,094 Republic of Ireland (ROI) volunteers and in 116 NI or ROI acromegaly/gigantism patients. Carrier frequencies were 0.0064 in Mid Ulster (95%CI = 0.0027-0.013; P = 0.0005 vs. ROI), 0.001 in Greater Belfast (0.00011-0.0047) and zero in ROI (0-0.0014). R304 * prevalence was elevated in acromegaly/gigantism patients in NI (11/87, 12.6%, P acromegaly/gigantism cases. tMRCA is consistent with historical/folklore accounts of Irish giants. Forward simulations predict many undetected carriers; geographically targeted population screening improves asymptomatic carrier identification, complementing clinical testing of patients/relatives. We generated disease awareness locally, necessary for early diagnosis and improved outcomes of AIP-related disease. © 2016 The Authors. **Human Mutation published by Wiley Periodicals, Inc.

  15. Discharge processes, electric field, and electron energy in ISUAL-recorded gigantic jets

    Science.gov (United States)

    Kuo, Cheng-Ling; Chou, J. K.; Tsai, L. Y.; Chen, A. B.; Su, H. T.; Hsu, R. R.; Cummer, S. A.; Frey, H. U.; Mende, S. B.; Takahashi, Y.; Lee, L. C.

    2009-04-01

    This article reports the first high time resolution measurements of gigantic jets from the Imager of Sprites and Upper Atmospheric Lightning (ISUAL) experiment. The velocity of the upward propagating fully developed jet stage of the gigantic jets was ˜107 m s-1, which is similar to that observed for downward sprite streamers. Analysis of spectral ratios for the fully developed jet emissions gives a reduced E field of 400-655 Td and average electron energy of 8.5-12.3 eV. These values are higher than those in the sprites but are similar to those predicted by streamer models, which implies the existence of streamer tips in fully developed jets. The gigantic jets studied here all contained two distinct photometric peaks. The first peak is from the fully developed jet, which steadily propagates from the cloud top (˜20 km) to the lower ionosphere at ˜90 km. We suggest that the second photometric peak, which occurs ˜1 ms after the first peak, is from a current wave or potential wave-enhanced emissions that originate at an altitude of ˜50 km and extend toward the cloud top. We propose that the fully developed jet serves as an extension of the local ionosphere and produces a lowered ionosphere boundary. As the attachment processes remove the charges, the boundary of the local ionosphere moves up. The current in the channel persists and its contact point with the ionosphere moves upward, which produces the upward surging trailing jets. Imager and photometer data indicate that the lightning activity associated with the gigantic jets likely is in-cloud, and thus the initiation of the gigantic jets is not directly associated with cloud-to-ground discharges.

  16. Bivalve aquaculture transfers in Atlantic Europe. Part A: Transfer activities and legal framework

    DEFF Research Database (Denmark)

    Muehlbauer, F.; Fraser, D.; Brenner, M.

    2014-01-01

    environment and address economic considerations remains unanswered. This study provides the first overview of bivalve transfer activities for aquaculture purposes along the European Atlantic coast. Existing international and EU legislation is described, and potential weaknesses in the existing legislative......Intentional transfers of numerous bivalve species have had a long tradition and are commonly conducted along the European Atlantic coast. However numerous studies have concluded that intentional transfer of species for aquaculture purposes is one of the most principal vectors for the introduction...... frameworks are discussed. Recommendations for the development of integrated risk assessment methods are given. These may help to minimize the intrinsic threats of transfer activities in marine environments. The resulting impacts and effects of transfer activities of bivalves for aquaculture purpose...

  17. Dioxin-like chemicals in bivalves and sediment collected from around Australia

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, J.F.; Muller, R.; Goudkamp, K. [EnTox, The University of Queensland, Brisbane (AU)] (and others)

    2004-09-15

    The aquatic environment is a significant sink for persistent organic pollutants including dioxin-like chemicals. Besides continuous investigations into sources of higher chlorinated PCDD that have initially been found in soils, and later in dugong and sediments little is known about the levels of dioxin-like chemicals in Australia's aquatic environment. In 2002 the National Dioxin Program (NDP) was commissioned by the Department of Environment and Heritage, Australia. One focus of the NDP was to evaluate background levels of dioxin-like chemicals in Australia's environment. One component of the 'Environmental Levels' project aimed to identify dioxinlike chemicals in the aquatic environment including bivalves collected in both marine, estuarine and freshwater systems. Here we report results from the NDP aquatic study with a particular emphasis on the levels of dioxin-like chemicals in bivalves and sediments respectively in areas from where the bivalves were collected.

  18. Labelling and marketing of bivalve and gastropod molluscs retailed in Sardinia, Italy between 2009 and 2013

    Directory of Open Access Journals (Sweden)

    Domenico Meloni

    2015-06-01

    Full Text Available The aim of the present survey was to investigate the correct enforcement of the Community rules on the labelling and marketing of bivalve and gastropod molluscs retailed in Sardinia, Italy between 2009 and 2013. A total of 1500 packages and labels for live bivalve and gastropod molluscs were considered. A total of 375 labels (25% presented non-compliance concerning the wrong trade name and additional wrong or missing information. The highest percentage of anomalous labels has been detected in small-scale retail shops (35% and open-air markets (25% compared with the big retailing chains (20%. The 5% of packages were not in compliance with the European Community rules on packaging of bivalve and gastropod molluscs. The high percentage of non-compliance with the European regulations on labelling results is a strong limitation for the consumers and highlights the need to improve the control system about labelling of seafood products.

  19. Labelling and Marketing of Bivalve and Gastropod Molluscs Retailed in Sardinia, Italy Between 2009 and 2013.

    Science.gov (United States)

    Meloni, Domenico

    2015-05-28

    The aim of the present survey was to investigate the correct enforcement of the Community rules on the labelling and marketing of bivalve and gastropod molluscs retailed in Sardinia, Italy between 2009 and 2013. A total of 1500 packages and labels for live bivalve and gastropod molluscs were considered. A total of 375 labels (25%) presented non-compliance concerning the wrong trade name and additional wrong or missing information. The highest percentage of anomalous labels has been detected in small-scale retail shops (35%) and open-air markets (25%) compared with the big retailing chains (20%). The 5% of packages were not in compliance with the European Community rules on packaging of bivalve and gastropod molluscs. The high percentage of non-compliance with the European regulations on labelling results is a strong limitation for the consumers and highlights the need to improve the control system about labelling of seafood products.

  20. SHRIMP (CRANGON-CRANGON L) BROWSING UPON SIPHON TIPS INHIBITS FEEDING AND GROWTH IN THE BIVALVE MACOMA-BALTHICA (L)

    NARCIS (Netherlands)

    KAMERMANS, P; HUITEMA, HJ

    1994-01-01

    The influence of siphon browsing on the feeding behaviour and growth of Macoma balthica, a deposit-feeding bivalve, was studied in three manipulative experiments. Browsing was simulated by removing part of the inhalant siphon with scissors, or studied by exposing the bivalves to shrimps (Crangon

  1. Phenology of abundance of bivalve spat and of their epibenthic predators: limited evidence for mismatches after cold winters

    NARCIS (Netherlands)

    Dekker, R.; Beukema, J.J.

    2014-01-01

    Annual recruitment of bivalves in the Wadden Sea is usually more successful in summers after cold than after mild winters. The new generation (0-group) of the main predators (shrimps and shore crabs) of early benthic stages of bivalves appear later in spring on tidal flats after colder winters. If

  2. An integrated ecosystem approach for assessing the potential role of cultivated bivalve shells as part of the carbon trading system

    NARCIS (Netherlands)

    Filgueira, R.; Byron, C.J.; Comeau, L.A.; Jansen, H.M.; Smaal, A.C.

    2015-01-01

    The role of bivalve mariculture in the CO2 cycle has been commonly evaluated as the balance between respiration, shell calcium carbonate sequestration and CO2 release during biogenic calcification. However, this approach neglects the ecosystem implications of cultivating bivalves at high densities,

  3. Bivalve aquaculture-environment interactions in the context of climate change.

    Science.gov (United States)

    Filgueira, Ramón; Guyondet, Thomas; Comeau, Luc A; Tremblay, Réjean

    2016-12-01

    Coastal embayments are at risk of impacts by climate change drivers such as ocean warming, sea level rise and alteration in precipitation regimes. The response of the ecosystem to these drivers is highly dependent on their magnitude of change, but also on physical characteristics such as bay morphology and river discharge, which play key roles in water residence time and hence estuarine functioning. These considerations are especially relevant for bivalve aquaculture sites, where the cultured biomass can alter ecosystem dynamics. The combination of climate change, physical and aquaculture drivers can result in synergistic/antagonistic and nonlinear processes. A spatially explicit model was constructed to explore effects of the physical environment (bay geomorphic type, freshwater inputs), climate change drivers (sea level, temperature, precipitation) and aquaculture (bivalve species, stock) on ecosystem functioning. A factorial design led to 336 scenarios (48 hydrodynamic × 7 management). Model outcomes suggest that the physical environment controls estuarine functioning given its influence on primary productivity (bottom-up control dominated by riverine nutrients) and horizontal advection with the open ocean (dominated by bay geomorphic type). The intensity of bivalve aquaculture ultimately determines the bivalve-phytoplankton trophic interaction, which can range from a bottom-up control triggered by ammonia excretion to a top-down control via feeding. Results also suggest that temperature is the strongest climate change driver due to its influence on the metabolism of poikilothermic organisms (e.g. zooplankton and bivalves), which ultimately causes a concomitant increase of top-down pressure on phytoplankton. Given the different thermal tolerance of cultured species, temperature is also critical to sort winners from losers, benefiting Crassostrea virginica over Mytilus edulis under the specific conditions tested in this numerical exercise. In general, it is

  4. A Darriwilian (Middle Ordovician bivalve-dominated molluscan fauna from the Stairway Sandstone, Amadeus Basin, central Australia

    Directory of Open Access Journals (Sweden)

    Kristian G. Jakobsen

    2016-12-01

    Full Text Available A bivalve-dominated molluscan fauna is described from the Darriwilian (Middle Ordovician Stairway Sandstone, Amadeus Basin, central Australia. The fauna comprises 16 species of bivalves and rostroconchs plus six gastropod species which are treated under open nomenclature. Two new bivalves, Sthenodonta paenesymmetrica sp. nov. and Modiolopsis pojetai sp. nov., are described. The relatively low-diverse molluscan fauna constitutes around 62% of the total benthic macrofauna. Approximately 75% of the molluscs comprise bivalves, especially nuculoids, which were biogeographically restricted to low latitudes during the Ordovician. The molluscan assemblage displays a very high degree of endemism at species level, though the bivalve Sthenodonta eastii also occurs in the Georgina Basin farther to the northeast. This indicates a possible marine connective seaway between the Georgina and Amadeus basins during the Darriwilian. Nuculites, Cyrtodonta, and Modiolopsis are cosmopolitan and previously reported from North China, Avalonia, and Southern Gondwana.

  5. Morphometric Studies on Anodonta Anatine Bivalve Population from the Dognecea Lake

    Directory of Open Access Journals (Sweden)

    Marian Bura

    2011-10-01

    Full Text Available In the Dognecea Lake, near town Bocsa in Caras-Severin county a strong bivalve population has been discovered from the duck mussel specie (Anodonta anatina. Harvested individuals were transported to the Aquaculture laboratory where measurements and correct identification was made. This specie is considered endangered but in Banat area, especially in the Dognecea Lake it is well represented, having an ecological importance, but the bivalve can have an economical importance too, due to the high percentage of edible part of 56.5%.

  6. In situ method for measurements of community clearance rate on shallow water bivalve populations

    DEFF Research Database (Denmark)

    Hansen, Benni W.; Dolmer, Per; Vismann, Bent

    2011-01-01

    An open-top chamber was designed for measuring ambient community clearance rate on undisturbed bivalve populations in the field. The chamber was pressed 5-10 cm down in the sediment on the mussel bed. It holds approximately 30-40 cm water column equal to a volume of 43-77 L. It was provided...... with an air lift connected to a SCUBA diver pressure tank generating a continuous and gentle water circulation. This ensures a complete mixture of suspended particles, and thereby, a maximum filtration by the bivalves. An in situ fluorometer was mounted to record plant pigment reduction due to mussel...

  7. Otimização do processo de depuração de moluscos bivalves

    OpenAIRE

    Correia, Maria Helena Oliveira Casimiro

    2016-01-01

    A contaminação microbiológica de moluscos bivalves constitui uma das principais preocupações inerentes à segurança alimentar desta importante fonte de receitas para a economia portuguesa. Os bivalves capturados ou produzidos em zonas estuarinas ou lagunares devem passar por um processo de depuração, para redução dos níveis de contaminação microbiológica, antes da sua comercialização. Este trabalho teve como principal objetivo o desenvolvimento de sistemas modulares de dep...

  8. Observations of Seven Blue/Gigantic Jets above One Storm over the Atlantic Ocean

    Science.gov (United States)

    Liu, N.; Spiva, N.; Dwyer, J. R.; Rassoul, H.; Free, D. L.; Cummer, S. A.

    2013-12-01

    Blue/gigantic jets are electrical discharges developing from thundercloud tops and propagating to the upper atmosphere [e.g., Pasko et al., Nature, 416, 152, 2002; Su et al., Nature, 423, 973, 2003]. Not just producing an impressive display, gigantic jets establish a direct path of electrical contact between the upper troposphere and the lower ionosphere, capable of transferring a large amount of charge between them [Cummer et al., Nat. Geosci., 2, 617, 2009]. It has been suggested that they may play an important role in the earth's electrical environment [e. g., Pasko, Nature, 423, 927, 2003]. Upward discharges from thunderstorms like blue/gigantic jets are believed to originate from lightning leaders escaping from thunderclouds when the cloud's charges of different polarities are not balanced [Krehbiel et al., Nat. Geosci., 1, 233, 2008; Riousset et al., JGR, 115, A00E10, 2010]. On the evening of August 2, 2013, 4 gigantic jets, 2 blue jets and 1 blue starter were recorded within 26 min above a storm over the Atlantic Ocean by a low light level camera from the campus of Florida Institute of Technology. The events were also captured by two all-sky cameras: one again from the Florida Tech campus and the other from a nearby location. According to the NLDN data, positive intra-cloud flashes preceded all events except one gigantic jet. The distance between the observation site to the locations of the NLDN lightning discharges varies from 77 to 82 km. Optical signatures of intra-cloud discharge activities accompanied the events are clearly visible in the videos. The duration of each jet varies from about 300 ms to 1.2 s, and the 1.2 s duration is probably the longest that has been reported to date for jets. Rebrightening of gigantic jet structures occurs for at least two of the events. The upper terminal altitude of the 4 gigantic jets is greater than 76-81 km, the 2 blue jets reach about 48 and 51 km altitude, respectively, and the blue starter reaches 24 km altitude

  9. A gigantic nothosaur (Reptilia: Sauropterygia) from the Middle Triassic of SW China and its implication for the Triassic biotic recovery

    Science.gov (United States)

    Liu, Jun; Hu, Shi-Xue; Rieppel, Olivier; Jiang, Da-Yong; Benton, Michael J.; Kelley, Neil P.; Aitchison, Jonathan C.; Zhou, Chang-Yong; Wen, Wen; Huang, Jin-Yuan; Xie, Tao; Lv, Tao

    2014-11-01

    The presence of gigantic apex predators in the eastern Panthalassic and western Tethyan oceans suggests that complex ecosystems in the sea had become re-established in these regions at least by the early Middle Triassic, after the Permian-Triassic mass extinction (PTME). However, it is not clear whether oceanic ecosystem recovery from the PTME was globally synchronous because of the apparent lack of such predators in the eastern Tethyan/western Panthalassic region prior to the Late Triassic. Here we report a gigantic nothosaur from the lower Middle Triassic of Luoping in southwest China (eastern Tethyan ocean), which possesses the largest known lower jaw among Triassic sauropterygians. Phylogenetic analysis suggests parallel evolution of gigantism in Triassic sauropterygians. Discovery of this gigantic apex predator, together with associated diverse marine reptiles and the complex food web, indicates global recovery of shallow marine ecosystems from PTME by the early Middle Triassic.

  10. Efficacy, safety, and pharmacokinetics of sustained-release lanreotide (lanreotide Autogel) in Japanese patients with acromegaly or pituitary gigantism.

    Science.gov (United States)

    Shimatsu, Akira; Teramoto, Akira; Hizuka, Naomi; Kitai, Kazuo; Ramis, Joaquim; Chihara, Kazuo

    2013-01-01

    The somatostatin analog lanreotide Autogel has proven to be efficacious for treating acromegaly in international studies and in clinical practices around the world. However, its efficacy in Japanese patients has not been extensively evaluated. We examined the dose-response relationship and long-term efficacy and safety in Japanese patients with acromegaly or pituitary gigantism. In an open-label, parallel-group, dose-response study, 32 patients (29 with acromegaly, 3 with pituitary gigantism) received 5 injections of 60, 90, or 120 mg of lanreotide Autogel over 24 weeks. Four weeks after the first injection, 41% of patients achieved serum GH level of gigantism) received lanreotide Autogel once every 4 weeks for a total of 13 injections. Dosing was initiated with 90 mg and adjusted according to clinical responses at Weeks 16 and/or 32. At Week 52, 47% of patients had serum GH levels of gigantism.

  11. Distribution of DTHS3 satellite DNA across 12 bivalve species Eva ...

    Indian Academy of Sciences (India)

    Windows User

    In this work, characterization of DTHS3 satellite DNA was further expanded within the Class. Bivalvia. Monomer variants of DTHS3 satDNA were compared in 12 bivalve species belonging to two different Subclasses, Heterodonta and Pteriomorphia. This satDNA, whose age is estimated to a minimum of 516 Ma, ...

  12. Shell growth and environmental control of methanophyllic Thyasirid bivalves from Svalbard cold seeps

    Science.gov (United States)

    Carroll, Michael; Åström, Emmelie; Ambrose, William; Locke, William; Oliver, Graham; Hong, Wei-Li; Carroll, JoLynn

    2016-04-01

    The analysis of molluscan shell material (sclerochronology) can provide information about an organism's age, growth history, and environmental conditions during its lifetime. Bivalve molluscs are common members of hydrothermal vents and methane cold seeps communities where, supported by chemosynthetic symbionts, they can reach high density and biomass. But little is known about methane-associated bivalve populations inhabiting high-Arctic cold seeps, and sclerochronological analysis of methane-influenced bivalves is rare. We measured growth rates and elemental and isotopic shell signatures in a newly discovered species of bivalve (Thyasiridae) from cold seeps at 350-390m depth southwest of Svalbard. First discovered in 2014, recently described shells of Thyasira capitanea sp.nov. were found at 2 independent seep systems in Storfjordrenna. Mean shell carbon isotopic ratios from inorganic δ13C (mean = -4.8‰) and organic δ13C (mean = -26.9‰) fractions clearly indicate a methane influenced habitat and food source for these organisms. Shell mineral ratios (Li/Ca, Mg/Ca, Mn/Ca, Fe/Ca, Sr/Ca, Ba/Ca, Pb/Ca) sampled along the axis of growth with laser-ablated ICP-MS exhibit variability through time and between sites, suggesting that concentrations of these elements that may be affected by methane emissions. The mineralogical data also elucidates the internal pattern of shell deposition and growth checks, and combined with the isotopic and growth rate data, enables us to interpret the temporal history of methane release from these locations.

  13. An ecosystem-based approach and management framework for the integrated evaluation of bivalve aquaculture impacts

    NARCIS (Netherlands)

    Cranford, P.J.; Kamermans, P.; Krause, G.H.M.; Mazurie, J.

    2012-01-01

    An ecosystem-based approach to bivalve aquaculture management is a strategy for the integration of aquaculture within the wider ecosystem, including human aspects, in such a way that it promotes sustainable development, equity, and resilience of ecosystems. Given the linkage between social and

  14. Burrowing Behavior of a Deposit Feeding Bivalve Predicts Change in Intertidal Ecosystem State

    NARCIS (Netherlands)

    Compton, T.J.; Bodnar, W.; Koolhaas, A.; Dekinga, A.; Holthuijsen, S.; Ten Horn, J.; McSweeney, N.; van Gils, J.A.; Piersma, T.

    2016-01-01

    Behavior has a predictive power that is often underutilized as a tool for signaling ecological change. The burrowing behavior of the deposit feeding bivalve Macoma balthica reflects a typical food-safety trade-off. The choice to live close to the sediment surface comes at a risk of predation and is

  15. Burrowing behavior of a deposit feeding bivalve predicts change in intertidal ecosystem state

    NARCIS (Netherlands)

    Compton, Tanya J.; Bodnar, Wanda; Koolhaas, Anita; Dekinga, Anne; Holthuijsen, Sander; ten Horn, Job; McSweeney, Niamh; van Gils, Jan; Piersma, Theunis

    2016-01-01

    Behavior has a predictive power that is often underutilized as a tool for signaling ecological change. The burrowing behavior of the deposit feeding bivalve Macoma balthica reflects a typical food-safety trade-off. The choice to live close to the sediment surface comes at a risk of predation and is

  16. Modiolarca lateralis (Pteryomorphia: Mytilidae: bivalve associated to six species of ascidians from Bocas del Toro, Panama

    Directory of Open Access Journals (Sweden)

    Juan I Cañete

    2013-11-01

    Full Text Available We describe the presence of the bivalve Modiolarca lateralis (Say, 1822 in six tropical ascidians Ascidia curvata, A. sydneiensis, A. panamensis, A. interrupta, Herdmania pallida and Polycarpa spongiabilis collected at depths of 1-3 m on coral reefs, mangrove roots and dock supports in Almirante Bay, Bocas del Toro, Panama (9°18'N, 82°13'W during June-July 2011. Bivalve prevalence varied between 9-30% across species, but was mainly associated with A. panamensis, P. spongiabilis and A. interrupta. Prevalence seems to be influenced by tunic thickness rather than by the ascidian size. Bivalves varied in size (0.6-11 mm shell length, with the smallest individual found in A. sydneiensis. There were only one or two bivalves per ascidians, although a maximum of 18 was found in one A. panamensis. M. lateralis seems to behave similarly to its temperate counterparts: it has a variety of hosts, occurs mainly in the anterior region of the ascidians, and has a variable abundance per host.

  17. Bivalve grazing, nutrient cycling and phytoplankton dynamics in an estuarine ecosystem

    NARCIS (Netherlands)

    Prins, T.C.

    1996-01-01


    This thesis has considered the impact of the suspension feeding bivalve Mytilusedulis on nutrient cycling and phytoplankton in an estuarine ecosystem. The research was started within the framework of an extensive research project with the

  18. Predation on intertidal mussels: Influence of biotic factors on the survival of epibenthic bivalve beds

    NARCIS (Netherlands)

    Waser, A.M.

    2018-01-01

    Coastal areas are amongst the most productive ecosystems in the world. Important components of these coastal areas are reef-forming bivalves such as mussels and oysters, as they have important facilitating effects on many associated organisms through the provision of substratum,

  19. Wood-Boring Bivalves (Mollusca: Teredinidae, Pholadidae) of Pacific coast of Colombia

    International Nuclear Information System (INIS)

    Cantera K, Jaime R

    2010-01-01

    Twelve species of wood-boring bivalves, ten of the family Teredinidae and two of family Pholadidae were collected in mangroves at 6 locations of the Pacific coast of Colombia. This paper presents a brief escription of these species, including size, ecological notes and geographical distribution.

  20. Gigantic Cosmic Corkscrew Reveals New Details About Mysterious Microquasar

    Science.gov (United States)

    2004-10-01

    Making an extra effort to image a faint, gigantic corkscrew traced by fast protons and electrons shot out from a mysterious microquasar paid off for a pair of astrophysicists who gained new insights into the beast's inner workings and also resolved a longstanding dispute over the object's distance. Microquasar SS 433 VLA Image of Microquasar SS 433 CREDIT: Blundell & Bowler, NRAO/AUI/NSF (Click on Image for Larger Version) The astrophysicists used the National Science Foundation's Very Large Array (VLA) radio telescope to capture the faintest details yet seen in the plasma jets emerging from the microquasar SS 433, an object once dubbed the "enigma of the century." As a result, they have changed scientists' understanding of the jets and settled the controversy over its distance "beyond all reasonable doubt," they said. SS 433 is a neutron star or black hole orbited by a "normal" companion star. The powerful gravity of the neutron star or black hole draws material from the stellar wind of its companion into an accretion disk of material tightly circling the dense central object prior to being pulled onto it. This disk propels jets of fast protons and electrons outward from its poles at about a quarter of the speed of light. The disk in SS 433 wobbles like a child's top, causing its jets to trace a corkscrew in the sky every 162 days. The new VLA study indicates that the speed of the ejected particles varies over time, contrary to the traditional model for SS 433. "We found that the actual speed varies between 24 percent to 28 percent of light speed, as opposed to staying constant," said Katherine Blundell, of the University of Oxford in the United Kingdom. "Amazingly, the jets going in both directions change their speeds simultaneously, producing identical speeds in both directions at any given time," Blundell added. Blundell worked with Michael Bowler, also of Oxford. The scientists' findings have been accepted by the Astrophysical Journal Letters. SS 433 New VLA

  1. Pituitary gigantism in a 31 month old girl: endocrine studies and successful response to hypophysectomy.

    Science.gov (United States)

    Espiner, E A; Carter, T A; Abbott, G D; Wrightson, P

    1981-01-01

    A case of pituitary gigantism occurring in a 31 month old female child is reported. Growth records indicate that the disorder began early in the second yr of life. Apart from her size and history of excessive sweating, there were no characteristic clinical features of endocrinopathy. Elevated and autonomous secretion of GH (60-109 microgram/l) and prolactin were corrected by the removal of an eosinophilic pituitary adenoma. In the subsequent 6 yr, despite the presence of immunoreactive GH (4.6-17.3 microgram/l), plasma somatomedin was subnormal and the patient showed growth failure which responded normally to exogenous GH therapy. This case, which appears to be the youngest example of verified pituitary gigantism on record, illustrates that a successful outcome can be achieved by surgical ablative therapy.

  2. Blue jets and gigantic jets: transient luminous events between thunderstorm tops and the lower ionosphere

    International Nuclear Information System (INIS)

    Pasko, V P

    2008-01-01

    An overview of general phenomenology and proposed physical mechanisms of large scale electrical discharges termed 'blue jets' and 'gigantic jets' observed at high altitude in the Earth's atmosphere above thunderstorms is presented. The primary emphasis is placed on summarizing available experimental data on the observed morphological features of upward jet discharges and on the discussion of recently advanced theories describing electrodynamic conditions, which facilitate escape of conventional lightning leaders from thundercloud tops and their upward propagation toward the ionosphere. It is argued that the filamentary plasma structures observed in blue jet and gigantic jet discharges are directly linked to the processes in streamer zones of lightning leaders, scaled by a significant reduction of air pressure at high altitudes.

  3. Cope's Rule and Romer's theory: patterns of diversity and gigantism in eurypterids and Palaeozoic vertebrates

    Science.gov (United States)

    Lamsdell, James C.; Braddy, Simon J.

    2010-01-01

    Gigantism is widespread among Palaeozoic arthropods, yet causal mechanisms, particularly the role of (abiotic) environmental factors versus (biotic) competition, remain unknown. The eurypterids (Arthropoda: Chelicerata) include the largest arthropods; gigantic predatory pterygotids (Eurypterina) during the Siluro-Devonian and bizarre sweep-feeding hibbertopterids (Stylonurina) from the Carboniferous to end-Permian. Analysis of family-level originations and extinctions among eurypterids and Palaeozoic vertebrates show that the diversity of Eurypterina waned during the Devonian, while the Placodermi radiated, yet Stylonurina remained relatively unaffected; adopting a sweep-feeding strategy they maintained their large body size by avoiding competition, and persisted throughout the Late Palaeozoic while the predatory nektonic Eurypterina (including the giant pterygotids) declined during the Devonian, possibly out-competed by other predators including jawed vertebrates. PMID:19828493

  4. Prolactin-secreting pituitary adenoma in a man with gigantism: a case report.

    Science.gov (United States)

    Peillon, F; Philippon, J; Brandi, A M; Fohanno, D; Laplane, D; Dubois, M P; Decourt, J

    1979-12-01

    A prolactin-secreting pituitary adenoma was removed trans-sphenoidally from a 37 years old man with gigantism (218 cm). Serum levels of prolactin (PRL) were elevated pre-operatively and decreased after administration of L-Dopa with no increase after TRH as is usually observed in PRL-secreting adenomas. Growth hormone (GH) and somatomedin serum levels were normal with no modification of GH after insulin hypoglycemia, oral glucose loading or L-Dopa. Morphological examination of the tumour demonstrated the presence of lactotrophs by light and electron microscopy and by immunofluorescense staining. No somatotrophs were found. In this unique case, the relationship between a PRL-secreting adenoma and gigantism is discussed.

  5. The use of bivalves as rapid, real-time indicators of aquatic pollution

    International Nuclear Information System (INIS)

    Markich, S.J.

    1995-01-01

    The ability of bivalves to filter large volumes of water on a daily basis, combined with the relatively high permeability of their cell membranes, make them valuable organisms to use in the contemporary detection of pollution. Bivalves are well known to respond to chemical contaminants by isolating their soft tissues from the aquatic medium by valve closure. The sensory acuity (via specialized sensory regions including the osphradium) and associated repertoire of this behavioral response can be employed to assess subtle effects exerted by chemical contaminants, such as complex effluents, that may ultimately influence the survival of these organisms. As hazard assessment tools, behavioral studies reflect sublethal toxicity and often yield a highly sensitive estimate of the lowest observable effect concentration (LOEC). Moreover, valve movement behavior has been identified as one of the more sensitive biological early warning measures to a variety of aquatic contaminants, in comparison with those used in other aquatic animal phyla. Therefore, the valve movement behavior of both freshwater (Hyridella depressa, Velesunio angasi and V. ambiguus) and marine (Mytilus edulis) bivalves was continuously monitored, using an on-line computer based data acquisition system, during exposure to either trace metals (e.g. Cu, Cd, Mn and U) or complex effluents (ie treated sewage effluent and acid leachate derived from contaminated Sydney Harbour sediments), in the context of using the valve movement behavior of the bivalve species to indicate the biological significance of exposure to the above-mentioned pollutants. The results indicate that several components of the valve movement behavior of each bivalve provide quantifiable and ecologically interpretable sub-lethal endpoints for the rapid and sensitive evaluation of waters containing either complex effluents or elevated levels of trace metals

  6. An overview of chemosynthetic symbioses in bivalves from the North Atlantic and Mediterranean Sea

    Science.gov (United States)

    Duperron, S.; Gaudron, S. M.; Rodrigues, C. F.; Cunha, M. R.; Decker, C.; Olu, K.

    2013-05-01

    Deep-sea bivalves found at hydrothermal vents, cold seeps and organic falls are sustained by chemosynthetic bacteria that ensure part or all of their carbon nutrition. These symbioses are of prime importance for the functioning of the ecosystems. Similar symbioses occur in other bivalve species living in shallow and coastal reduced habitats worldwide. In recent years, several deep-sea species have been investigated from continental margins around Europe, West Africa, eastern Americas, the Gulf of Mexico, and from hydrothermal vents on the Mid-Atlantic Ridge. In parallel, numerous, more easily accessible shallow marine species have been studied. Herein we provide a summary of the current knowledge available on chemosymbiotic bivalves in the area ranging west-to-east from the Gulf of Mexico to the Sea of Marmara, and north-to-south from the Arctic to the Gulf of Guinea. Characteristics of symbioses in 53 species from the area are summarized for each of the five bivalve families documented to harbor chemosynthetic symbionts (Mytilidae, Vesicomyidae, Solemyidae, Thyasiridae and Lucinidae). Comparisons are made between the families, with special emphasis on ecology, life cycle, and connectivity. Chemosynthetic symbioses are a major adaptation to ecosystems and habitats exposed to reducing conditions. However, relatively little is known regarding their diversity and functioning, apart from a few "model species" on which effort has focused over the last 30 yr. In the context of increasing concern about biodiversity and ecosystems, and increasing anthropogenic pressure on oceans, we advocate a better assessment of the diversity of bivalve symbioses in order to evaluate the capacities of these remarkable ecological and evolutionary units to withstand environmental change.

  7. First records of Freshwater Bivalves of Ilha Grande National Park, Paraná, Brazil

    Directory of Open Access Journals (Sweden)

    Flávio Henrique Ragonha

    2014-03-01

    Full Text Available The Ilha Grande National Park, Paraná, Brazil, is located in the Upper Paraná River and has characteristics typical of a floodplains. This protected area includes lagoons connected and disconnected to the Paraná River, although the latter also connect during periods of high water level, thus composing a heterogeneous group of lacustrine environments. The enormous potential the flora and fauna diversities are still little known to the region, as can be seen through benthic invertebrates, inclunding bivalves mollusks. The granulometric composition of these floodplain lagoons was formed mainly by mud and very fine sand. Furthermore, organic matter composition was predominantly of fine particulate. The other abiotic factors differed from lagoons located within the island of the park to those located in the left margin of Paraná River. The results demonstrated the importance of abiotic factors such as the physical composition of granulometric texture, organic matter and macrophyte banks, to the establishment of bivalves in these floodplain lagoons. We recorded bivalves of Pisidium (native, Diplodon (native, and Corbicula (invasive. The highest values of Diplodon sp. density were observed at São João/C lake, for Pisidium sterkianum (Pilsbry, 1897 at São João/M lake, and to Jatobá/C lagoon with high density of invasive species Corbicula fluminea (Müller, 1774. This study to obtain conduct the first records of freshwater bivalves in floodplains lagoon in the Ilha Grande National Park, and provides contributions to better understanding the ecology of these mollusks. The recording of native species in the region of Upper Paraná River floodplain after a lomg period without new records, demonstrated the importance of protecting the lagoons of the Ilha Grande National Park as they can be a possible refuge to some species of native freshwater bivalves.

  8. An overview of chemosynthetic symbioses in bivalves from the North Atlantic and Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    S. Duperron

    2013-05-01

    Full Text Available Deep-sea bivalves found at hydrothermal vents, cold seeps and organic falls are sustained by chemosynthetic bacteria that ensure part or all of their carbon nutrition. These symbioses are of prime importance for the functioning of the ecosystems. Similar symbioses occur in other bivalve species living in shallow and coastal reduced habitats worldwide. In recent years, several deep-sea species have been investigated from continental margins around Europe, West Africa, eastern Americas, the Gulf of Mexico, and from hydrothermal vents on the Mid-Atlantic Ridge. In parallel, numerous, more easily accessible shallow marine species have been studied. Herein we provide a summary of the current knowledge available on chemosymbiotic bivalves in the area ranging west-to-east from the Gulf of Mexico to the Sea of Marmara, and north-to-south from the Arctic to the Gulf of Guinea. Characteristics of symbioses in 53 species from the area are summarized for each of the five bivalve families documented to harbor chemosynthetic symbionts (Mytilidae, Vesicomyidae, Solemyidae, Thyasiridae and Lucinidae. Comparisons are made between the families, with special emphasis on ecology, life cycle, and connectivity. Chemosynthetic symbioses are a major adaptation to ecosystems and habitats exposed to reducing conditions. However, relatively little is known regarding their diversity and functioning, apart from a few "model species" on which effort has focused over the last 30 yr. In the context of increasing concern about biodiversity and ecosystems, and increasing anthropogenic pressure on oceans, we advocate a better assessment of the diversity of bivalve symbioses in order to evaluate the capacities of these remarkable ecological and evolutionary units to withstand environmental change.

  9. Linking changes in subcellular cadmium distribution to growth and mortality rates in transplanted freshwater bivalves (Pyganodon grandis)

    International Nuclear Information System (INIS)

    Perceval, Olivier; Couillard, Yves; Pinel-Alloul, Bernadette; Campbell, Peter G.C.

    2006-01-01

    Relationships between Cd accumulation and subcellular distribution, and growth and mortality rates were examined in the freshwater bivalve Pyganodon grandis in a transplant experiment. Organisms were transferred from a clean lacustrine site to four lakes situated along a Cd concentration gradient in the mining region of Rouyn-Noranda. The bivalves were maintained in open enclosures placed in the bottom sediments of the littoral zone of all five lakes for 400 days. At the end of the experiment, metallothionein (MT) was measured in the bivalve gills with a Hg-saturation assay and Cd partitioning among the various cytosolic protein pools was determined by size-exclusion chromatography. Marked differences were observed among the five sites: the range in calculated free-cadmium ion concentrations in water overlying the sediments was 35-fold whereas Cd concentrations in the gill cytosol of the transplanted bivalves varied three-fold. In the transplanted bivalves, the distribution of gill Cd among the various cytosolic complexes also varied significantly among sites. For bivalves transplanted to the three most contaminated sites, Cd concentrations in the high molecular weight pool (HMW > 25 kDa) were significantly higher than the baseline levels determined from bivalves caged at the reference site; a similar trend was seen for Cd concentrations in the metallothionein pool (Cd-MT). For bivalves transferred to two of the high contamination sites, proportionately less of the gill cytosolic Cd was sequestered (i.e. detoxified) by MT-like proteins. Reductions in survival were also observed at these two sites, and these elevated mortalities, in turn, were consistent with the absence of indigenous bivalve populations at these sites. This result is compatible with our recent work on P. grandis populations living in lakes of the Rouyn-Noranda area, in which we demonstrated that excessive accumulation of Cd in the HMW pool of the gill cytosol of the individual mollusks could be

  10. Hepatocarcinoma gigante unifocal en mujer con ingesta prolongada de anticonceptivos hormonales: ¿casualidad o causalidad?

    OpenAIRE

    VICTOR MANUEL LOPEZ MOURIÑO; JOSÉ LOPEZ CASTRO; BENIGNO MONTEAGUDO SANCHEZ; ENRIQUE JESÚS ALVAREZ ASENSIO

    2016-01-01

    Presentamos un caso de una paciente de mediana edad con ingesta mantenida de anticonceptivos hormonales (AH) que desarrolla múltiples adenomas hepáticos (asociación bien documentada) y un carcinoma hepatocelular (CHC) unifocal gigante sin encontrar otros factores de riesgo para el mismo (enolismo, tabaquismo, cirrosis, hemocromatosis,....). Si bien en la literatura no hay unanimidad respecto a la asociación del consumo de AH con el CHC, algunos autores ya contemplaron esa posibilidad, excluye...

  11. An Evolutionary Cascade Model for Sauropod Dinosaur Gigantism - Overview, Update and Tests

    OpenAIRE

    Sander, P. Martin

    2013-01-01

    Sauropod dinosaurs are a group of herbivorous dinosaurs which exceeded all other terrestrial vertebrates in mean and maximal body size. Sauropod dinosaurs were also the most successful and long-lived herbivorous tetrapod clade, but no abiological factors such as global environmental parameters conducive to their gigantism can be identified. These facts justify major efforts by evolutionary biologists and paleontologists to understand sauropods as living animals and to explain their evolutiona...

  12. CT of the "Tegernsee Giant": juvenile gigantism and polyostotic fibrous dysplasia.

    Science.gov (United States)

    Vogl, T J; Nerlich, A; Dresel, S H; Bergman, C

    1994-01-01

    We report the radiological findings in the unusual case of the Bavarian "Tegernsee Giant." With conventional radiography, CT, and histologic examination, we succeeded in diagnosing two disorders: The Tegernsee Giant suffered from (a) juvenile gigantism caused by a growth hormone-secreting tumor of the pituitary gland and (b) a polyostotic form of fibrous dysplasia of the skull and multiple bones particularly on the left side of the body.

  13. Unilateral delayed opercularization in a case of Sotos' syndrome (cerebral gigantism)

    Energy Technology Data Exchange (ETDEWEB)

    Barth, P.G.; Vlasveld, L.; Valk, J.

    1980-08-01

    A case of Sotos' syndrome (cerebral gigantism) is described. Pneumencephalography, performed at the age of 15 days, revealed abnormal separation of the opercula on the right. By comparing the contours with developmental anatomical features of this area it agreed with a foetal development of 24 weeks gestational age. Bilateral carotid angiography was normal. CT showed normal development of the Sylvian area at the age of 27 months.

  14. Breast vasculitis in association with breast gigantism in a pregnant patient with systemic lupus erythematosus.

    Science.gov (United States)

    Propper, D J; Reid, D M; Stankler, L; Eastmond, C J

    1991-01-01

    A 24 year old woman with systemic lupus erythematosus (SLE) developed widespread necrotic skin ulceration and gigantism of both breasts during an exacerbation of SLE in the last trimester of her second pregnancy. Over the remainder of the pregnancy the ulceration was only controlled by high dose corticosteroids. After parturition, however, it was possible to reduce the steroid dose without recurrence of the ulceration. Images PMID:1888201

  15. Unilateral delayed opercularization in a case of Sotos' syndrome (cerebral gigantism)

    International Nuclear Information System (INIS)

    Barth, P.G.; Vlasveld, L.; Valk, J.

    1980-01-01

    A case of Sotos' syndrome (cerebral gigantism) is described. Pneumencephalography, performed at the age of 15 days, revealed abnormal separation of the opercula on the right. By comparing the contours with developmental anatomical features of this area it agreed with a foetal development of 24 weeks gestational age. Bilateral carotid angiography was normal. CT showed normal development of the Sylvian area at the age of 27 months. (orig.)

  16. PITUITARY GIGANTISM--EXPERIENCE OF A SINGLE CENTER FROM WESTERN INDIA.

    Science.gov (United States)

    Patt, Hiren P; Bothra, Nikita; Goel, Atul H; Kasaliwal, Rajeev; Lila, Anurag R; Bandgar, Tushar R; Shah, Nalini S

    2015-06-01

    Limited data are available on pituitary gigantism, as it is a rare disorder. This study was carried out to assess the clinical, hormonal, and radiologic profiles and management outcomes of patients with pituitary gigantism. We conduced a retrospective analysis of 14 patients with pituitary gigantism who presented to a single tertiary care institute from 1990 to 2014. Thirteen patients were male, and 1 was female. The mean age at diagnosis was 21.9 ± 6.1 years, with a mean lag period of 6.5 ± 5.6 years. The mean height SD score at the time of diagnosis was 3.2 ± 0.6. Symptoms of tumor mass effect were the chief presenting complaint in the majority (50%) of patients, while 2 patients were asymptomatic. Six patients had hyperprolactinemia. At presentation, the nadir PGGH (postglucose GH) and insulin-like growth factor (IGF 1)-ULN (× upper limit of normal) were 63.2 ± 94.9 ng/mL and 1.98 ± 0.5, respectively. All (except 1 with mild pituitary hyperplasia) had pituitary macroadenoma. Six patients had invasive pituitary adenoma. Transsphenoidal surgery (TSS) was the primary modality of treatment in 13/14 patients, and it achieved remission in 4/13 (30.76%) patients without recurrence over a median follow-up of 7 years. Post-TSS radiotherapy (RT) achieved remission in 3/5 (60%) patients over a median follow-up of 3.5 years. None of the patients received medical management at any point of time. Gigantism is more common in males, and remission can be achieved in the majority of the patients with the help of multimodality treatment (TSS and RT).

  17. Underground cosmic-ray measurement for morphological reconstruction of the ''Grotta Gigante'' natural cave

    International Nuclear Information System (INIS)

    Caffau, E.; Coren, F.; Giannini, G.

    1997-01-01

    Measurement of the muon flux as a function of direction inside the Grotta Gigante natural cave near Trieste (Italy) was carried out using a tracking apparatus. The measured flux, depending in a well established way on the zenith angle and the rock mass crossed by the muons, allowed the determination of the shape of the cave vault which could be compared with that known from topography and related to the available microgravimetric data of the area. (orig.)

  18. Change in the immunophenotype of a somatotroph adenoma resulting in gigantism

    OpenAIRE

    Thawani, Jayesh P.; Bailey, Robert L.; Burns, Carrie M.; Lee, John Y. K.

    2014-01-01

    Background: Examining the pathologic progression of a pituitary adenoma from the point of a prepubescent child to an adult with gigantism affords us an opportunity to consider why patients may develop secretory or functioning tumors and raises questions about whether therapeutic interventions and surveillance strategies could be made to avoid irreversible phenotypic changes. Case Description: A patient underwent a sublabial transsphenoidal resection for a clinically non-functioning macroa...

  19. Starvation reveals the cause of infection-induced castration and gigantism.

    Science.gov (United States)

    Cressler, Clayton E; Nelson, William A; Day, Troy; McCauley, Edward

    2014-10-07

    Parasites often induce life-history changes in their hosts. In many cases, these infection-induced life-history changes are driven by changes in the pattern of energy allocation and utilization within the host. Because these processes will affect both host and parasite fitness, it can be challenging to determine who benefits from them. Determining the causes and consequences of infection-induced life-history changes requires the ability to experimentally manipulate life history and a framework for connecting life history to host and parasite fitness. Here, we combine a novel starvation manipulation with energy budget models to provide new insights into castration and gigantism in the Daphnia magna-Pasteuria ramosa host-parasite system. Our results show that starvation primarily affects investment in reproduction, and increasing starvation stress reduces gigantism and parasite fitness without affecting castration. These results are consistent with an energetic structure where the parasite uses growth energy as a resource. This finding gives us new understanding of the role of castration and gigantism in this system, and how life-history variation will affect infection outcome and epidemiological dynamics. The approach of combining targeted life-history manipulations with energy budget models can be adapted to understand life-history changes in other disease systems.

  20. Starvation reveals the cause of infection-induced castration and gigantism

    Science.gov (United States)

    Cressler, Clayton E.; Nelson, William A.; Day, Troy; McCauley, Edward

    2014-01-01

    Parasites often induce life-history changes in their hosts. In many cases, these infection-induced life-history changes are driven by changes in the pattern of energy allocation and utilization within the host. Because these processes will affect both host and parasite fitness, it can be challenging to determine who benefits from them. Determining the causes and consequences of infection-induced life-history changes requires the ability to experimentally manipulate life history and a framework for connecting life history to host and parasite fitness. Here, we combine a novel starvation manipulation with energy budget models to provide new insights into castration and gigantism in the Daphnia magna–Pasteuria ramosa host–parasite system. Our results show that starvation primarily affects investment in reproduction, and increasing starvation stress reduces gigantism and parasite fitness without affecting castration. These results are consistent with an energetic structure where the parasite uses growth energy as a resource. This finding gives us new understanding of the role of castration and gigantism in this system, and how life-history variation will affect infection outcome and epidemiological dynamics. The approach of combining targeted life-history manipulations with energy budget models can be adapted to understand life-history changes in other disease systems. PMID:25143034

  1. Independent evolution of baleen whale gigantism linked to Plio-Pleistocene ocean dynamics.

    Science.gov (United States)

    Slater, Graham J; Goldbogen, Jeremy A; Pyenson, Nicholas D

    2017-05-31

    Vertebrates have evolved to gigantic sizes repeatedly over the past 250 Myr, reaching their extreme in today's baleen whales (Mysticeti). Hypotheses for the evolution of exceptionally large size in mysticetes range from niche partitioning to predator avoidance, but there has been no quantitative examination of body size evolutionary dynamics in this clade and it remains unclear when, why or how gigantism evolved. By fitting phylogenetic macroevolutionary models to a dataset consisting of living and extinct species, we show that mysticetes underwent a clade-wide shift in their mode of body size evolution during the Plio-Pleistocene. This transition, from Brownian motion-like dynamics to a trended random walk towards larger size, is temporally linked to the onset of seasonally intensified upwelling along coastal ecosystems. High prey densities resulting from wind-driven upwelling, rather than abundant resources alone, are the primary determinant of efficient foraging in extant mysticetes and Late Pliocene changes in ocean dynamics may have provided an ecological pathway to gigantism in multiple independent lineages. © 2017 The Author(s).

  2. Ecological explanations to island gigantism: dietary niche divergence, predation, and size in an endemic lizard.

    Science.gov (United States)

    Runemark, Anna; Sagonas, Kostas; Svensson, Erik I

    2015-08-01

    Although rapid evolution of body size on islands has long been known, the ecological mechanisms behind this island phenomenon remain poorly understood. Diet is an important selective pressure for morphological divergence. Here we investigate if selection for novel diets has contributed to the multiple independent cases of island gigantism in the Skyros wall lizard (Podarcis gaigeae) and if diet, predation, or both factors best explain island gigantism. We combined data on body size, shape, bite force, and realized and available diets to address this. Several lines of evidence suggest that diet has contributed to the island gigantism. The larger islet lizards have relatively wider heads and higher bite performance in relation to mainland lizards than would be expected from size differences alone. The proportions of consumed and available hard prey are higher on islets than mainland localities, and lizard body size is significantly correlated with the proportion of hard prey. Furthermore, the main axis of divergence in head shape is significantly correlated with dietary divergence. Finally, a model with only diet and one including diet and predation regime explain body size divergence equally well. Our results suggest that diet is an important ecological factor behind insular body size divergence, but could be consistent with an additional role for predation.

  3. Regional endothermy as a trigger for gigantism in some extinct macropredatory sharks.

    Directory of Open Access Journals (Sweden)

    Humberto G Ferrón

    Full Text Available Otodontids include some of the largest macropredatory sharks that ever lived, the most extreme case being Otodus (Megaselachus megalodon. The reasons underlying their gigantism, distribution patterns and extinction have been classically linked with climatic factors and the evolution, radiation and migrations of cetaceans during the Paleogene. However, most of these previous proposals are based on the idea of otodontids as ectothermic sharks regardless of the ecological, energetic and body size constraints that this implies. Interestingly, a few recent studies have suggested the possible existence of endothermy in these sharks thus opening the door to a series of new interpretations. Accordingly, this work proposes that regional endothermy was present in otodontids and some closely related taxa (cretoxyrhinids, playing an important role in the evolution of gigantism and in allowing an active mode of live. The existence of regional endothermy in these groups is supported here by three different approaches including isotopic-based approximations, swimming speed inferences and the application of a novel methodology for assessing energetic budget and cost of swimming in extinct taxa. In addition, this finding has wider implications. It calls into question some previous paleotemperature estimates based partially on these taxa, suggests that the existing hypothesis about the evolution of regional endothermy in fishes requires modification, and provides key evidence for understanding the evolution of gigantism in active macropredators.

  4. Regional endothermy as a trigger for gigantism in some extinct macropredatory sharks.

    Science.gov (United States)

    Ferrón, Humberto G

    2017-01-01

    Otodontids include some of the largest macropredatory sharks that ever lived, the most extreme case being Otodus (Megaselachus) megalodon. The reasons underlying their gigantism, distribution patterns and extinction have been classically linked with climatic factors and the evolution, radiation and migrations of cetaceans during the Paleogene. However, most of these previous proposals are based on the idea of otodontids as ectothermic sharks regardless of the ecological, energetic and body size constraints that this implies. Interestingly, a few recent studies have suggested the possible existence of endothermy in these sharks thus opening the door to a series of new interpretations. Accordingly, this work proposes that regional endothermy was present in otodontids and some closely related taxa (cretoxyrhinids), playing an important role in the evolution of gigantism and in allowing an active mode of live. The existence of regional endothermy in these groups is supported here by three different approaches including isotopic-based approximations, swimming speed inferences and the application of a novel methodology for assessing energetic budget and cost of swimming in extinct taxa. In addition, this finding has wider implications. It calls into question some previous paleotemperature estimates based partially on these taxa, suggests that the existing hypothesis about the evolution of regional endothermy in fishes requires modification, and provides key evidence for understanding the evolution of gigantism in active macropredators.

  5. [Digital gigantism of the foot: a clinical study of 12 cases].

    Science.gov (United States)

    Wang, Hai-hua; Tian, Guang-lei; Zhu, Yin; Zhang, You-le; Zhao, Jun-hui; Tian, Wen

    2008-03-15

    To summarize the clinical characteristic and outcome of digital gigantism of the foot. Retrospectively analyze the clinical documents of cases of digital gigantism of the foot. Twelve 12 cases with 13 feet in this study included 8 male and 4 female with an average 4.6-years-old. All the deformities were found at birth. Multiple toes involved were more than single toe, and tibial toe involved more than fibular. Forefoot was enlarged. All the phalanges involved and partial metatarsal bones were enlarged. Marked increase in subcutaneous fat was found in all cases in the operation which infiltrated interossei and articular capsules. The appearance of the nerves and its branches in the foot were normal and fat infiltrating was not discovered. The operation types included debulking, epiphyseal arrest, amputation, nerve stripping and anastomosis. Seven cases were followed up with mean periods 25.6 months. Functional evaluation according to a criterion formulated by author revealed a result of 2 excellent, 2 good and 3 fair. Digital gigantism of the foot is an uncommon congenital deformity of the foot characterized by overgrowth of both the soft-tissue and the osseous elements of the enlarged toe and forefoot. Surgical treatment is the unique method, and the goal is to reduce the size of the foot to allow fitting regular shoes and walking readily. There are several types of operations which to be chosen. The indication, the timing of operative intervention and the selection of operation type should be paid more attention.

  6. Some effects of temperature and starvation on the bivalve @iDonax vittatus@@ (da Costa) in experimental laboratory populations

    Digital Repository Service at National Institute of Oceanography (India)

    Ansell, A.D.; Sivadas, P.

    The effect of temperature on the body weight and composition, and on respiration, filtration and NH, excretion of the bivalve Donax uittatus (da Costa) has been investigated in laboratory-maintained populations under conditions of starvation In all...

  7. Sensitivity of Mediterranean bivalve mollusc aquaculture to climate change, ocean acidification, and other environmental pressures: findings from a producers’ survey

    NARCIS (Netherlands)

    Rodrigues, L.; van den Bergh, J.C.J.M.; Mass, F.; Theodorou, J.A.; Ziveri, P.; Gazeau, F.

    2015-01-01

    Human-induced climate change and ocean acidification are global environmental phenomena with a common driver: anthropogenic emissions of carbon dioxide. Both processes potentially threaten the Mediterranean bivalve mollusc aquaculture sector, which is economically relevant to several regions and

  8. Anodontites trapesialis (LAMARCK, 1819: a bivalve parasite of freshwater fishes / Anodontites trapesialis (LAMARCK, 1819: um bivalve parasito de peixes de água doce

    Directory of Open Access Journals (Sweden)

    Ângela Teresa Silva-Souza

    2008-08-01

    Full Text Available The bivalve mollusk Anodontites trapesialis has been indicated as an alternative source for aquaculture because it is considered a food of good nutritional value with a protein content close to that of fish. Its shells can be utilized as fertilizer and mixed to the food of domestic animals, and the nacre can be used to manufacture buttons and crafts. However, the larvae of A. trapesialis, which are the lasidium type, are obligatory parasites of freshwater fishes, and the introduction of this bivalve in fish farm tanks have caused trouble and losses for producers. Nothing is known, however, about their development in these environments. On the other hand, it should be pointed out that A. trapesialis is on Brazil’s list of species threatened with extinction. This article provides a compilation of information present in the literature, offering a detailed review, with the aim of presenting a general panorama of what is known about Anodontites trapesialis and its larval parasitism of fishes.O molusco bivalve, Anodontites trapesialis, tem sido indicado como fonte alternativa para a aqüicultura, por ser considerado um alimento de bom valor nutricional com um conteúdo protéico próximo ao do pescado. Suas conchas podem ser utilizadas como fertilizantes calcáreos e ser agregadas a alimentos de animais domésticos e o nácar pode ser utilizado para fabricar botões e artesanatos. No entanto, as larvas de A. trapesialis, que são do tipo lasidium, são parasitas obrigatórias de peixes de água doce e a introdução desse bivalve em tanques de piscicultura tem causado transtornos e prejuízos aos produtores. Nada se conhece, porém, sobre o seu desenvolvimento nesses ambientes. Por outro lado, ressalta-se que A. trapesialis consta da lista brasileira de espécies ameaçadas de extinção. No presente artigo são compiladas as informações presentes na literatura, em uma revisão detalhada, com o objetivo de apresentar o panorama geral do

  9. Trophic Dynamics of Filter Feeding Bivalves in the Yangtze Estuarine Intertidal Marsh: Stable Isotope and Fatty Acid Analyses

    Science.gov (United States)

    Wang, Sikai; Jin, Binsong; Qin, Haiming; Sheng, Qiang; Wu, Jihua

    2015-01-01

    Benthic bivalves are important links between primary production and consumers, and are essential intermediates in the flow of energy through estuarine systems. However, information on the diet of filter feeding bivalves in estuarine ecosystems is uncertain, as estuarine waters contain particulate matter from a range of sources and as bivalves are opportunistic feeders. We surveyed bivalves at different distances from the creek mouth at the Yangtze estuarine marsh in winter and summer, and analyzed trophic dynamics using stable isotope (SI) and fatty acid (FA) techniques. Different bivalve species had different spatial distributions in the estuary. Glauconome chinensis mainly occurred in marshes near the creek mouth, while Sinonovacula constricta preferred the creek. Differences were found in the diets of different species. S. constricta consumed more diatoms and bacteria than G. chinensis, while G. chinensis assimilated more macrophyte material. FA markers showed that plants contributed the most (38.86 ± 4.25%) to particular organic matter (POM) in summer, while diatoms contributed the most (12.68 ± 1.17%) during winter. Diatoms made the largest contribution to the diet of S. constricta in both summer (24.73 ± 0.44%) and winter (25.51 ± 0.59%), and plants contributed no more than 4%. This inconsistency indicates seasonal changes in food availability and the active feeding habits of the bivalve. Similar FA profiles for S. constricta indicated that the bivalve had a similar diet composition at different sites, while different δ13C results suggested the diet was derived from different carbon sources (C4 plant Spartina alterniflora and C3 plant Phragmites australis and Scirpus mariqueter) at different sites. Species-specific and temporal and/or spatial variability in bivalve feeding may affect their ecological functions in intertidal marshes, which should be considered in the study of food webs and material flows in estuarine ecosystems. PMID:26261984

  10. Combined treatment with octreotide LAR and pegvisomant in patients with pituitary gigantism: clinical evaluation and genetic screening.

    Science.gov (United States)

    Mangupli, Ruth; Rostomyan, Liliya; Castermans, Emilie; Caberg, Jean-Hubert; Camperos, Paul; Krivoy, Jaime; Cuauro, Elvia; Bours, Vincent; Daly, Adrian F; Beckers, Albert

    2016-10-01

    Pituitary gigantism is a rare condition caused by growth hormone secreting hypersecretion, usually by a pituitary tumor. Acromegaly and gigantism cases that have a genetic cause are challenging to treat, due to large tumor size and poor responses to some medical therapies (e.g. AIP mutation affected cases and those with X-linked acrogigantism syndrome). We performed a retrospective study to identify gigantism cases among 160 somatotropinoma patients treated between 1985 and 2015 at the University Hospital of Caracas, Venezuela. We studied clinical details at diagnosis, hormonal responses to therapy and undertook targeted genetic testing. Among the 160 cases, eight patients (six males; 75 %) were diagnosed with pituitary gigantism and underwent genetic analysis that included array comparative genome hybridization for Xq26.3 duplications. All patients had GH secreting pituitary macroadenomas that were difficult to control with conventional treatment options, such as surgery or primary somatostatin receptor ligand (SRL) therapy. Combined therapy (long-acting SRL and pegvisomant) as primary treatment or after pituitary surgery and radiotherapy permitted the normalization of IGF-1 levels and clinical improvement. Novel AIP mutations were the found in three patients. None of the patients had Xq26.3 microduplications. Treatment of pituitary gigantism is frequently challenging; delayed control increases the harmful effects of GH excess, such as, excessive stature and symptom burden, so early diagnosis and effective treatment are particularly important in these cases.

  11. Current Opinion in Endocrinology, Diabetes, and Obesity “Pituitary gigantism: Update on Molecular Biology and Management”

    Science.gov (United States)

    Lodish, Maya B.; Trivellin, Giampaolo; Stratakis, Constantine A.

    2016-01-01

    Purpose of review To provide an update on the mechanisms leading to pituitary gigantism, as well as to familiarize the practitioner with the implication of these genetic findings on treatment decisions. Recent findings Prior studies have identified gigantism as a feature of a number of monogenic disorders, including mutations in the aryl hydrocarbon receptor interacting protein (AIP) gene, multiple endocrine neoplasia types 1 and 4, McCune Albright Syndrome, Carney Complex, and the paraganglioma, pheochromocytoma and pituitary adenoma association (3PA) due to succinate dehydrogenase defects. We recently described a previously uncharacterized form of early-onset pediatric gigantism caused by microduplications on chromosome Xq26.3 and we termed it X-LAG (X-linked acrogigantism). The age of onset of increased growth in X-LAG is significantly younger than other pituitary gigantism cases, and control of growth hormone excess is particularly challenging. Summary Knowledge of the molecular defects that underlie pituitary tumorigenesis is crucial for patient care as they guide early intervention, screening for associated conditions, genetic counseling, surgical approach (partial or total hypophysectomy), and choice of medical management. Recently described microduplications of Xq26.3 account for more than 80% of the cases of early-onset pediatric gigantism. Early recognition of X-LAG may improve outcomes, as successful control of growth hormone excess requires extensive anterior pituitary resection and are difficult to manage with medical therapy alone. PMID:26574647

  12. Proteomic Profiling of Cytosolic Glutathione Transferases from Three Bivalve Species: Corbicula fluminea, Mytilus galloprovincialis and Anodonta cygnea

    Directory of Open Access Journals (Sweden)

    José Carlos Martins

    2014-01-01

    Full Text Available Suspension-feeding bivalves are considered efficient toxin vectors with a relative insensitivity to toxicants compared to other aquatic organisms. This fact highlights the potential role of detoxification enzymes, such as glutathione transferases (GSTs, in this bivalve resistance. Nevertheless, the GST system has not been extensively described in these organisms. In the present study, cytosolic GSTs isoforms (cGST were surveyed in three bivalves with different habitats and life strategies: Corbicula fluminea, Anodonta cygnea and Mytilus galloprovincialis. GSTs were purified by glutathione-agarose affinity chromatography, and the collection of expressed cGST classes of each bivalve were identified using a proteomic approach. All the purified extracts were also characterized kinetically. Results reveal variations in cGST subunits collection (diversity and properties between the three tested bivalves. Using proteomics, four pi-class and two sigma-class GST subunits were identified in M. galloprovincialis. C. fluminea also yielded four pi-class and one sigma-class GST subunits. For A. cygnea, two mu-class and one pi-class GST subunits were identified, these being the first record of GSTs from these freshwater mussels. The affinity purified extracts also show differences regarding enzymatic behavior among species. The variations found in cGST collection and kinetics might justify diverse selective advantages for each bivalve organism.

  13. Contamination of raw bivalve molluscs available in Poland between 2009 and 2013 with marine biotoxins

    Directory of Open Access Journals (Sweden)

    Michalski Mirosław

    2016-12-01

    Full Text Available Introduction: Growing consumption of shellfish is associated with an increased risk of food poisoning. The study was carried out on live bivalve molluscs available on the Polish market between 2009 and 2013. Material and Methods: ELISA was used for the determination of the following marine biotoxins: paralytic shellfish poison (PSP, amnaesic shellfish poison (ASP, and diarrhoeic shellfish poison (DSP. The molluscs, of which seven species were examined, were obtained from wholesale companies and markets. Results: Marine biotoxins were detected below the permitted levels in 67.6% of the samples. The maximum amounts of PSP and ASP biotoxins were found in great scallops (532.6 μg/kg and 1.0 mg/kg respectively and the peak for DSP was in blue mussels (107 μg/kg. Conclusion: The analysis of toxicological status of raw bivalve molluscs available on the market in Poland indicates that they are safe for consumers.

  14. An ecosystem-based approach and management framework for the integrated evaluation of bivalve aquaculture impacts

    DEFF Research Database (Denmark)

    Cranford, Peter J.; Kamermans, Pauline; Krause, Gesche

    2012-01-01

    for bivalve aquaculture be based on a tiered indicator monitoring system that is structured on the principle that increased environmental risk requires increased monitoring effort. More than 1 threshold for each indicator would permit implementation of predetermined impact prevention and mitigation measures......An ecosystem-based approach to bivalve aquaculture management is a strategy for the integration of aquaculture within the wider ecosystem, including human aspects, in such a way that it promotes sustainable development, equity, and resilience of ecosystems. Given the linkage between social...... and ecological systems, marine regulators require an ecosystem-based decision framework that structures and integrates the relationships between these systems and facilitates communication of aquaculture–environment interactions and policy-related developments and decisions. The Drivers-Pressures-State Change-Impact-Response...

  15. Ocean acidification increases cadmium accumulation in marine bivalves: a potential threat to seafood safety.

    Science.gov (United States)

    Shi, Wei; Zhao, Xinguo; Han, Yu; Che, Zhumei; Chai, Xueliang; Liu, Guangxu

    2016-01-21

    To date, the effects of ocean acidification on toxic metals accumulation and the underlying molecular mechanism remains unknown in marine bivalve species. In the present study, the effects of the realistic future ocean pCO2 levels on the cadmium (Cd) accumulation in the gills, mantle and adductor muscles of three bivalve species, Mytilus edulis, Tegillarca granosa, and Meretrix meretrix, were investigated. The results obtained suggested that all species tested accumulated significantly higher Cd (p ocean acidification-induced increase in Cd accumulation may have occurred due to (i) the ocean acidification increased the concentration of Cd and the Cd(2+)/Ca(2+) in the seawater, which in turn increased the Cd influx through Ca channel; (ii) the acidified seawater may have brought about epithelia damage, resulting in easier Cd penetration; and (iii) ocean acidification hampered Cd exclusion.

  16. Metals and organotins in multiple bivalve species in a one-off global survey

    DEFF Research Database (Denmark)

    Larsen, Martin Mørk; Strand, Jakob; Christensen, Jan H.

    2011-01-01

    contamination levels on a global scale. Metal concentrations in nine bivalve species were normalised to the Mytilidae family using conversion factors based on cosampled species and literature bioconcentration factors. The lowest metal and tributyltin concentrations were below background assessment...... were low, but not always lower than expected impacted areas. The most contaminated areas were harbours, where especially Copenhagen, St Croix and Sydney, can be considered hotspots of tributyltin as well as a number of metals....

  17. An ecosystem-based approach and management framework for the integrated evaluation of bivalve aquaculture impacts

    OpenAIRE

    Cranford, Peter J.; Kamermans, Pauline; Krause, Gesche; Mazurie, Joseph; Buck, Bela H.; Dolmer, Per; Fraser, David; Van Nieuwenhove, Kris; O'Beirn, Francis X.; Sanchez-mata, Adoracion; Thorarinsdottir, Gudrun G.; Strand, Oivind

    2012-01-01

    An ecosystem-based approach to bivalve aquaculture management is a strategy for the integration of aquaculture within the wider ecosystem, including human aspects, in such a way that it promotes sustainable development, equity, and resilience of ecosystems. Given the linkage between social and ecological systems, marine regulators require an ecosystem-based decision framework that structures and integrates the relationships between these systems and facilitates communication of aquaculture–en...

  18. Semi-automatic surface sediment sampling system - A prototype to be implemented in bivalve fishing surveys

    Science.gov (United States)

    Rufino, Marta M.; Baptista, Paulo; Pereira, Fábio; Gaspar, Miguel B.

    2018-01-01

    In the current work we propose a new method to sample surface sediment during bivalve fishing surveys. Fishing institutes all around the word carry out regular surveys with the aim of monitoring the stocks of commercial species. These surveys comprise often more than one hundred of sampling stations and cover large geographical areas. Although superficial sediment grain sizes are among the main drivers of benthic communities and provide crucial information for studies on coastal dynamics, overall there is a strong lack of this type of data, possibly, because traditional surface sediment sampling methods use grabs, that require considerable time and effort to be carried out on regular basis or on large areas. In face of these aspects, we developed an easy and un-expensive method to sample superficial sediments, during bivalve fisheries monitoring surveys, without increasing survey time or human resources. The method was successfully evaluated and validated during a typical bivalve survey carried out on the Northwest coast of Portugal, confirming that it had any interference with the survey objectives. Furthermore, the method was validated by collecting samples using a traditional Van Veen grabs (traditional method), which showed a similar grain size composition to the ones collected by the new method, on the same localities. We recommend that the procedure is implemented on regular bivalve fishing surveys, together with an image analysis system to analyse the collected samples. The new method will provide substantial quantity of data on surface sediment in coastal areas, using a non-expensive and efficient manner, with a high potential application in different fields of research.

  19. Impact of seawater carbonate chemistry on the calcification of marine bivalves

    OpenAIRE

    Thomsen Jörn; Haynert Kristin; Wegner K Mathias; Melzner Frank

    2015-01-01

    Bivalve calcification, particular of the early larval stages is highly sensitive to the change of ocean carbonate chemistry resulting from atmospheric CO2 uptake. Earlier studies suggested that declining seawater [CO32−] and thereby lowered carbonate saturation affect shell production. However, disturbances of physiological processes such as acid-base regulation by adverse seawater pCO2 and pH can affect calcification in a secondary fashion. In order to determine the e...

  20. Ecology of megabenthic bivalve communities from sandy beaches on the south coast of Portugal

    Directory of Open Access Journals (Sweden)

    Marta M. Rufino

    2010-03-01

    Full Text Available Ecological aspects of 75 megabenthic bivalve species found on the south coast of Portugal (from Vila Real to Sagres were studied based on the information provided by seasonal bivalve surveys from 2000 to 2007 (8600 hauls, simultaneously using a razor shell dredge and a clam dredge. Of the 75 species identified, 36 occurred less than 30 times, and thus were considered rare in the area. The remaining 39 bivalves were analysed according to their occurrence, bathymetric distribution, geographic preferences, seasonal preferences, burying-depth, beach exposure and river mouth proximity. All species belonging to the Pharidae and Solenidae families (razor shells and most Tellinidae were significantly more frequent in the razor shell dredge (indicating deeper burying in the sediment, whilst the families Cardiidae and Donacidae were significantly more frequent in the clam dredge (indicating that these species are probably closer to the sediment surface. As for the season, most bivalve species occurred similarly in both seasons (19 sp; 49%, but a large proportion were more abundant during the autumn surveys (17 sp., 44%, whereas only three species were commoner during the spring surveys. Most species belonging to the families Cardiidae and Mactridae were commoner in the autumn surveys. The spatial distribution differed between species and cluster analysis identified four communities with greater geographic affinity. Species belonging to the family Cardiidae were preferably found in the western part (WB and the eastern part (S of the study area, whereas the families Donacidae, Mactridae and Tellinidae occurred mainly in the central area (EB and the eastern (S coastal sectors. Overall, shallower species (modal depth at 3-6 m showed greater occurrences and abundances than the deeper ones, and the depth pattern observed did not change between seasons. Donacidae and Mactridae (except Mactra glauca were represented essentially by shallow species, whereas

  1. Bioaccumulation of selected metals in bivalves (Unionidae) and Phragmites australis inhabiting a municipal water reservoir

    OpenAIRE

    Rzymski, Piotr; Niedzielski, Przemysław; Klimaszyk, Piotr; Poniedziałek, Barbara

    2014-01-01

    Urbanization can considerably affect water reservoirs by, inter alia, input, and accumulation of contaminants including metals. Located in the course of River Cybina, Maltański Reservoir (Western Poland) is an artificial shallow water body built for recreation and sport purposes which undergoes restoration treatment (drainage) every 4 years. In the present study, we demonstrate an accumulation of nine metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Zn) in water, sediment, three bivalve species (Anodo...

  2. Availability of pearl producing marine bivalves in south-eastern coast of Bangladesh and culture potentialities

    Directory of Open Access Journals (Sweden)

    Md Ataur Rahman

    2015-12-01

    Full Text Available The present study was conducted during September 2014 to July 2015 to identify the pearl bearing bivalves in south-eastern coast of Bangladesh and culture potentialities of marine oyster in captivity based on field investigation. A total of 7 pearl bearing bivalve species were identified in the coast with a salinity of 18-34 ppt, pH 8.1-8.3 and water depth ranged 0.2-2.0 meter in their habitat. From the collected bivalves, most abundant oyster species windowpane oyster, Placuna placenta (Linnaeus, 1758 was reared in fiber glass tanks with seawater for a period of 6 months. During rearing highest survival rate of 88% was observed in T1 with sandy and gravel substratum and lowest survival rate of 78% was found in T2 with muddy substratum. Average temperature and salinity were varied between 24 °C-25 °C and 21-26 ppt respectively. From the reared oyster, highest 54 nos. small pearls in the month of April and lowest 7 pearls in December from a single P. placenta were obtained. The study proved that pearls can be obtained from the marine oysters in captivity in Bangladesh, and this offers large scale culture potentialities in our coast.

  3. EU Regulatory Risk Management of Marine Biotoxins in the Marine Bivalve Mollusc Food-Chain

    Directory of Open Access Journals (Sweden)

    Micheál O’Mahony

    2018-03-01

    Full Text Available Food safety risk assessment in the European Union (EU recognises consumer illness that arises from marine biotoxins as a risk associated with bivalve mollusc consumption. EU food regulations contain various general food safety obligations, which should contribute significantly to managing this risk. EU food regulations additionally impose various specific obligations on both Food Business Operators and Competent Authorities in order to manage the marine biotoxin food safety risk in the bivalve mollusc food-chain. These have a particular focus on the pre-harvest component of the food-chain. A central component of these specific systems is the requirement for ongoing monitoring of phytoplankton and biotoxin concentrations in water and molluscs, respectively. This monitoring explicitly brings a potential outcome of closing production areas delineated by classification to prohibit the harvest of bivalve molluscs as food from those areas when acceptable biotoxin concentrations are exceeded. This review considers the utility of these systems, at conceptual and practical levels, and explores their contribution to an effective regulatory risk management approach.

  4. Chemosynthetic bacteria found in bivalve species from mud volcanoes of the Gulf of Cadiz.

    Science.gov (United States)

    Rodrigues, Clara F; Webster, Gordon; Cunha, Marina R; Duperron, Sébastien; Weightman, Andrew J

    2010-09-01

    As in other cold seeps, the dominant bivalves in mud volcanoes (MV) from the Gulf of Cadiz are macrofauna belonging to the families Solemyidae (Acharax sp., Petrasma sp.), Lucinidae (Lucinoma sp.), Thyasiridae (Thyasira vulcolutre) and Mytilidae (Bathymodiolus mauritanicus). The delta(13)C values measured in solemyid, lucinid and thyasirid specimens support the hypothesis of thiotrophic nutrition, whereas isotopic signatures of B. mauritanicus suggest methanotrophic nutrition. The indication by stable isotope analysis that chemosynthetic bacteria make a substantial contribution to the nutrition of the bivalves led us to investigate their associated bacteria and their phylogenetic relationships based on comparative 16S rRNA gene sequence analysis. PCR-denaturing gradient gel electrophoresis analysis and cloning of bacterial 16S rRNA-encoding genes confirmed the presence of sulfide-oxidizing symbionts within gill tissues of many of the studied specimens. Phylogenetic analysis of bacterial 16S rRNA gene sequences demonstrated that most bacteria were related to known sulfide-oxidizing endosymbionts found in other deep-sea chemosynthetic environments, with the co-occurrence of methane-oxidizing symbionts in Bathymodiolus specimens. This study confirms the presence of several chemosynthetic bivalves in the Gulf of Cadiz and further highlights the importance of sulfide- and methane-oxidizing symbionts in the trophic ecology of macrobenthic communities in MV.

  5. Climate change and body size shift in Mediterranean bivalve assemblages: unexpected role of biological invasions.

    Science.gov (United States)

    Nawrot, Rafał; Albano, Paolo G; Chattopadhyay, Devapriya; Zuschin, Martin

    2017-08-16

    Body size is a synthetic functional trait determining many key ecosystem properties. Reduction in average body size has been suggested as one of the universal responses to global warming in aquatic ecosystems. Climate change, however, coincides with human-enhanced dispersal of alien species and can facilitate their establishment. We address effects of species introductions on the size structure of recipient communities using data on Red Sea bivalves entering the Mediterranean Sea through the Suez Canal. We show that the invasion leads to increase in median body size of the Mediterranean assemblage. Alien species are significantly larger than native Mediterranean bivalves, even though they represent a random subset of the Red Sea species with respect to body size. The observed patterns result primarily from the differences in the taxonomic composition and body-size distributions of the source and recipient species pools. In contrast to the expectations based on the general temperature-size relationships in marine ectotherms, continued warming of the Mediterranean Sea indirectly leads to an increase in the proportion of large-bodied species in bivalve assemblages by accelerating the entry and spread of tropical aliens. These results underscore complex interactions between changing climate and species invasions in driving functional shifts in marine ecosystems. © 2017 The Author(s).

  6. Dinophysis caudata generated lipophilic shellfish toxins in bivalves from the Nanji Islands, East China Sea

    Science.gov (United States)

    Jiang, Tao; Xu, Yixiao; Li, Yang; Qi, Yuzao; Jiang, Tianjiu; Wu, Feng; Zhang, Fan

    2014-01-01

    A 12-month program of monitoring potentially toxic microalgae (that produce lipophilic shellfish toxins; LSTs) and their toxins in bivalves was conducted from April 2006 to March 2007 in the Nanji Islands, East China Sea. Two Dinophysis species, D. caudata and D. acuminata, were identified, and D. caudata was found to be the dominant species. D. caudata was detected in water samples between April and June 2006, and between February and March 2007. It reached its highest abundances in May, with a mean abundance of 1.38×102 cells/L in surface water and 1.25×102 cells/L in bottom water (cultured bivalves sampled between April and June were contaminated with LSTs, with an average toxicity of 85 μg okadaic acid (OA) eq./100 g meat, which was four times higher than the Chinese regulatory limit (20 μg OA eq./100 g meat). Ten out of fifteen wild samples (66.7%) collected during the same period were positive for LSTs, and contained an average LST toxicity of 45 μg OA eq./100 g meat (more than twice the regulatory value). Cultured Patinopecten yessoensis collected on 15 May 2006 had the highest toxicity, 320 μg OA eq./100 g meat, and relatively high toxicities (80 to 160 μg OA eq./100 g meat) were found in bivalves until the end of July.

  7. EU Regulatory Risk Management of Marine Biotoxins in the Marine Bivalve Mollusc Food-Chain.

    Science.gov (United States)

    O'Mahony, Micheál

    2018-03-10

    Food safety risk assessment in the European Union (EU) recognises consumer illness that arises from marine biotoxins as a risk associated with bivalve mollusc consumption. EU food regulations contain various general food safety obligations, which should contribute significantly to managing this risk. EU food regulations additionally impose various specific obligations on both Food Business Operators and Competent Authorities in order to manage the marine biotoxin food safety risk in the bivalve mollusc food-chain. These have a particular focus on the pre-harvest component of the food-chain. A central component of these specific systems is the requirement for ongoing monitoring of phytoplankton and biotoxin concentrations in water and molluscs, respectively. This monitoring explicitly brings a potential outcome of closing production areas delineated by classification to prohibit the harvest of bivalve molluscs as food from those areas when acceptable biotoxin concentrations are exceeded. This review considers the utility of these systems, at conceptual and practical levels, and explores their contribution to an effective regulatory risk management approach.

  8. Coexisting diseases modifying each other’s presentation - lack of growth failure in Turner syndrome due to the associated pituitary gigantism

    OpenAIRE

    Dragović Tamara; Đuran Zorana; Jelić Svetlana; Marinković Dejan; Kiković Saša; Kuzmić-Janković Snežana; Hajduković Zoran

    2016-01-01

    Introduction. Turner syndrome presents with one of the most frequent chromosomal aberrations in female, typically presented with growth retardation, ovarian insufficiency, facial dysmorphism, and numerous other somatic stigmata. Gigantism is an extremely rare condition resulting from an excessive growth hormone (GH) secretion that occurs during childhood before the fusion of epiphyseal growth plates. The major clinical feature of gigantism is growth acceler...

  9. The effect on infection of irradiated fasciola gigantic (liver flukes) on goats (Capra hircus linn) blood values

    International Nuclear Information System (INIS)

    Tuasikal, BJ.; M-Arifin; Yusneti; Dinardi; Suhardono

    2006-01-01

    This experiment was carried out to study the effect of infection Fasciola gigantic irradiated by using 60 Co to goat’s blood values. Twenty local male goats, ten to twelve old months, 115-20 kg of body weight were used for this study. The animals were divided into 5 groups consisting of four replications. Three groups received irradiated metacercariae of Fasciola gigantic a using 45, 55 and 65 Gy respectively. One group in the positive control and another one is the negative control. Each goat received 350 metacercariae. The study in was undertaken for 25 weeks. Body weight, Eosinofil, PCV and Hb were measured. These indicated that infectivity reduced on irradiated Fasciola gigantic. In all parameters, among negative control group and three irradiation-groups showed non significant (p>0,05). (author)

  10. Evaluation of γ-radiation-induced DNA damage in two species of bivalves and their relative sensitivity using comet assay.

    Science.gov (United States)

    Praveen Kumar, M K; Shyama, S K; Sonaye, B S; Naik, U Roshini; Kadam, S B; Bipin, P D; D'costa, A; Chaubey, R C

    2014-05-01

    Ionizing radiation is known to induce genetic damage in diverse groups of organisms. Under accidental situations, large quantities of radioactive elements get released into the environment and radiation emitted from these radionuclides may adversely affect both the man and the non-human biota. The present study is aimed (a) to know the genotoxic effect of gamma radiation on aquatic fauna employing two species of selected bivalves, (b) to evaluate the possible use of 'Comet assay' for detecting genetic damage in haemocytes of bivalves as a biomarker for environmental biomonitoring and also (c) to compare the relative sensitivity of two species of bivalves viz. Paphia malabarica and Meretrix casta to gamma radiation. The comet assays was optimized and validated using different concentrations (18, 32 and 56 mg/L) of ethyl methanesulfonate (EMS), a direct-acting reference genotoxic agent, to which the bivalves were exposed for various times (24, 48 and 72 h). Bivalves were irradiated (single acute exposure) with 5 different doses (viz. 2, 4, 6, 8 and 10 Gy) of gamma radiation and their genotoxic effects on the haemocytes were studied using the comet assay. Haemolymph was collected from the adductor muscle at 24, 48 and 72 h of both EMS-exposed and irradiated bivalves and comet assay was carried out using standard protocol. A significant increase in DNA damage was observed as indicated by an increase in % tail DNA damage at different concentrations of EMS and all the doses of gamma radiation as compared to controls in both bivalve species. This showed a dose-dependent increase of genetic damage induced in bivalves by EMS as well as gamma radiation. Further, the highest DNA damage was observed at 24h. The damage gradually decreased with time, i.e. was smaller at 48 and 72 h than at 24h post irradiation in both species of bivalves. This may indicate repair of the damaged DNA and/or loss of heavily damaged cells as the post irradiation time advanced. The present study

  11. Immune response of cattle against fasciolopsis induced by inoculation of irradiated metacercariae of fasciola gigantic

    International Nuclear Information System (INIS)

    M-Arifin

    2006-01-01

    An experiment was carried out to study the immune response of cattle against fasciolopsis induced by inoculation of irradiated metacercariae of F. gigantic. Four groups of experimental cattle were used e.g: the first group (Vp) were inoculated by the unirradiated metacercariae as a positive control, the second group (Vi) were once inoculated with irradiated metacercariae and then challenged with the infected metacercariae three weeks later, the third group (Vii) were twice inoculated with irradiated metacercariae and then challenged with the infected metacercariae three weeks later, while the forth group (Vn), the negative control without any inoculation of metacercariae. Irradiation dose of 45 Gy was used, and each experimental animal received 700 live’s metacercariae of F. gigantic. The immune response towards fasciolopsis in cattle has been observed in the development of body weight, the number of red blood cells (RBC), the number of white blood cells (WBC), level of haemoglobin (Hb), percentages of Packed cell volume (PCV), the number of eosinophil cells, serological test by ELISA, pathology anatomic inspection and evaluation of the development of worm.The average every measurement of body weight development are Vp = 6 kg, Vi = 9 kg, Vii = 9 kg and Vn = 10 kg. The group of Vi, Vii and Vn were normal of their heart, but the group of Vp was disorder. The group of Vi, Vii and Vn were negative of adult worm’s, while the group of Vp was positive of adult worm’s. These results showed that inoculation of irradiated metacercariae F. gigantic could stimulate good immune response which was able to protect against the infectivity of the challenge in cattle. (author)

  12. Clinical and genetic characterization of pituitary gigantism: an international collaborative study in 208 patients.

    Science.gov (United States)

    Rostomyan, Liliya; Daly, Adrian F; Petrossians, Patrick; Nachev, Emil; Lila, Anurag R; Lecoq, Anne-Lise; Lecumberri, Beatriz; Trivellin, Giampaolo; Salvatori, Roberto; Moraitis, Andreas G; Holdaway, Ian; Kranenburg-van Klaveren, Dianne J; Chiara Zatelli, Maria; Palacios, Nuria; Nozieres, Cecile; Zacharin, Margaret; Ebeling, Tapani; Ojaniemi, Marja; Rozhinskaya, Liudmila; Verrua, Elisa; Jaffrain-Rea, Marie-Lise; Filipponi, Silvia; Gusakova, Daria; Pronin, Vyacheslav; Bertherat, Jerome; Belaya, Zhanna; Ilovayskaya, Irena; Sahnoun-Fathallah, Mona; Sievers, Caroline; Stalla, Gunter K; Castermans, Emilie; Caberg, Jean-Hubert; Sorkina, Ekaterina; Auriemma, Renata Simona; Mittal, Sachin; Kareva, Maria; Lysy, Philippe A; Emy, Philippe; De Menis, Ernesto; Choong, Catherine S; Mantovani, Giovanna; Bours, Vincent; De Herder, Wouter; Brue, Thierry; Barlier, Anne; Neggers, Sebastian J C M M; Zacharieva, Sabina; Chanson, Philippe; Shah, Nalini Samir; Stratakis, Constantine A; Naves, Luciana A; Beckers, Albert

    2015-10-01

    Despite being a classical growth disorder, pituitary gigantism has not been studied previously in a standardized way. We performed a retrospective, multicenter, international study to characterize a large series of pituitary gigantism patients. We included 208 patients (163 males; 78.4%) with growth hormone excess and a current/previous abnormal growth velocity for age or final height >2 s.d. above country normal means. The median onset of rapid growth was 13 years and occurred significantly earlier in females than in males; pituitary adenomas were diagnosed earlier in females than males (15.8 vs 21.5 years respectively). Adenomas were ≥10 mm (i.e., macroadenomas) in 84%, of which extrasellar extension occurred in 77% and invasion in 54%. GH/IGF1 control was achieved in 39% during long-term follow-up. Final height was greater in younger onset patients, with larger tumors and higher GH levels. Later disease control was associated with a greater difference from mid-parental height (r=0.23, P=0.02). AIP mutations occurred in 29%; microduplication at Xq26.3 - X-linked acrogigantism (X-LAG) - occurred in two familial isolated pituitary adenoma kindreds and in ten sporadic patients. Tumor size was not different in X-LAG, AIP mutated and genetically negative patient groups. AIP-mutated and X-LAG patients were significantly younger at onset and diagnosis, but disease control was worse in genetically negative cases. Pituitary gigantism patients are characterized by male predominance and large tumors that are difficult to control. Treatment delay increases final height and symptom burden. AIP mutations and X-LAG explain many cases, but no genetic etiology is seen in >50% of cases. © 2015 Society for Endocrinology.

  13. The parasitic castration and gigantism of Lymnaea truncatula infected with the larval stages of Fasciola hepatica.

    Science.gov (United States)

    Wilson, R A; Denison, J

    1980-01-01

    The shells of Lymnaea truncatula infected with the larval stages of Fasciola hepatica were significantly longer than those of comparable uninfected controls. The dry mass (tissue, shell + parasite) of the same infected snails, 56 days after infection, was approximately twice that of the controls (tissue + shell). The increased mass of infected snails was not due to a disproportionate increase in shell weight relative to tissues. Infected snails maintained at 20 degrees C had virtually ceased egg production by 21 days post-infection whereas control snails continued to lay eggs steadily for the duration of the experiment. The dry mass of snail tissue plus the cumulative dry weight of eggs produced was taken as an indication of the ability of control snails to generate biomass. Similarly the tissue mass plus cumulative egg weight and parasite weight was taken as an indication of the ability of the infected snails to generate biomass. The control and infected snails were not significantly different in this respect indicating that the gigantism of infected snails could be the result of a switch in nutrient supply from reproduction to somatic tissue growth and parasite growth. Castration was brought about 17-21 days after infection as a result of the direct consumption of the ovotestis by a proportion of the redial population. In a separate experiment it was demonstrated that a population of infected snails maintained at 20 degrees C survived as long as a similar group of control snails. The findings with this host-parasite system are discussed in relation to possible mechanisms causing castration and gigantism in other digene-snail interactions, and in relation to parasitic castration in other groups. It is concluded that the observed gigantism of infected snails is more likely to have a nutritional rather than endocrine origin.

  14. Unusual AIP mutation and phenocopy in the family of a young patient with acromegalic gigantism

    OpenAIRE

    Syed Ali Imran; Khaled A Aldahmani; Lynette Penney; Sidney E Croul; David B Clarke; Donato Iacovazzo; Márta Korbonits

    2018-01-01

    Summary Early-onset acromegaly causing gigantism is often associated with aryl-hydrocarbon-interacting receptor protein (AIP) mutation, especially if there is a positive family history. A15y male presented with tiredness and visual problems. He was 201 cm tall with a span of 217 cm. He had typical facial features of acromegaly, elevated IGF-1, secondary hypogonadism and a large macroadenoma. His paternal aunt had a history of acromegaly presenting at the age of 35 years. Following transspheno...

  15. Bariones y gravitones gigantes en el marco de la correspondencia AdS/CFT

    OpenAIRE

    Picos Sol, Marco Antonio

    2012-01-01

    Se construyen y analizan dos tipos de configuraciones que pueden construirse en el espacio dual a la teoría ABJM (en la dualidad AdS_4/CFT_3): gravitones gigantes y vértices bariónicos. Ambas configuraciones hacen uso de la posibilidad de enrrollar branas en ciclos topológicamente no triviales en el lado gravitatorio de la dualidad. Los vértices bariónicos están formados por branas enrrolladas atadas a cuerdas que se extienden hasta la frontera de AdS, y son vistos desde el lado gauge com...

  16. Formación y evolución de planetas gigantes

    Science.gov (United States)

    Benvenuto, O. G.; Brunini, A.

    Presentamos el estado actual del trabajo que estamos realizando en el estudio de la formación de planetas gigantes. Detallamos los algoritmos numéricos necesarios para realizar este tipo de cálculo. Presentamos algunos resultados de la formación de objetos con masas de hasta una docena de veces la del planeta Júpiter, resaltando las principales caracteríticas. Finalmente detallamos los problemas que pensamos abordar en un futuro cercano en este tema de investigación.

  17. Vínculos observacionais para o processo-S em estrelas gigantes de Bário

    Science.gov (United States)

    Smiljanic, R. H. S.; Porto de Mello, G. F.; da Silva, L.

    2003-08-01

    Estrelas de bário são gigantes vermelhas de tipo GK que apresentam excessos atmosféricos dos elementos do processo-s. Tais excessos são esperados em estrelas na fase de pulsos térmicos do AGB (TP-AGB). As estrelas de bário são, no entanto, menos massivas e menos luminosas que as estrelas do AGB, assim, não poderiam ter se auto-enriquecido. Seu enriquecimento teria origem em uma estrela companheira, inicialmente mais massiva, que evolui pelo TP-AGB, se auto-enriquece com os elementos do processo-s e transfere material contaminado para a atmosfera da atual estrela de bário. A companheira evolui então para anã branca deixando de ser observada diretamente. As estrelas de bário são, portanto, úteis como testes observacionais para teorias de nucleossíntese pelo processo-s, convecção e perda de massa. Análises detalhadas de abundância com dados de alta qualidade para estes objetos são ainda escassas na literatura. Neste trabalho construímos modelos de atmosferas e, procedendo a uma análise diferencial, determinamos parâmetros atmosféricos e evolutivos de uma amostra de dez gigantes de bário e quatro normais. Determinamos seus padrões de abundância para Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, Y, Zr, Ba, La, Ce, Nd, Sm, Eu e Gd, concluindo que algumas estrelas classificadas na literatura como gigantes de bário são na verdade gigantes normais. Comparamos dois padrões médios de abundância, para estrelas com grandes excessos e estrelas com excessos moderados, com modelos teóricos de enriquecimento pelo processo-s. Os dois grupos de estrelas são ajustados pelos mesmos parâmetros de exposição de nêutrons. Tal resultado sugere que a ocorrência do fenômeno de bário com diferentes intensidades não se deve a diferentes exposições de nêutrons. Discutimos ainda efeitos nucleossintéticos, ligados ao processo-s, sugeridos na literatura para os elementos Cu, Mn, V e Sc.

  18. Gigantic uniaxial pressure effect in single crystals of iron-based superconductors

    International Nuclear Information System (INIS)

    Nakashima, Y.; Yui, H.; Sasagawa, T.

    2010-01-01

    In order to elucidate the anisotropic pressure effect on superconductivity in an iron-based superconductor, magnetization measurements have been performed in Ba(Fe 0.92 Co 0.08 ) 2 As 2 single crystals under uniaxial pressures applied along the c-axis. Gigantic T c suppression, dT c /dP //c = -15 K/GPa, was observed when the anisotropic deformation with the a-expansion and c-compression was induced by the c-pressure, which should be compared with dT c /dP c .

  19. Gigantic uphill drift of vacancies and self-interstitials in silicon

    International Nuclear Information System (INIS)

    Voronkov, V.V.; Falster, R.

    2009-01-01

    Point defect transport in a growing crystal includes a drift along the temperature gradient, G, at a velocity αG. It was not clear if the drift is negligible or strong in silicon crystal growth. It is now found that reported microdefect patterns in crystals grown with a temporarily halt provide a clear evidence in favour of a strong (even gigantic) drift of both kinds of intrinsic point defects. The drift coefficients α V (for vacancies) and α I (for self-interstitials) are deduced by fitting the simulating defect profiles to the observed location of halt-induced interstitial region immersed into a vacancy-type crystal.

  20. Uncharted waters: Bivalves of midway atoll and integrating mathematics into biology education

    Science.gov (United States)

    McCully, Kristin M.

    To protect and conserve the Earth's biodiversity and ecosystem services, it is important not only to understand and conserve species and ecosystems, but also to instill an understanding and appreciation for biodiversity and ecosystem services in the next generations of both scientists and citizens. Thus, this dissertation combines research into the ecology and identity of large bivalves at Midway Atoll in the Northwestern Hawaiian Islands (NWHI) with research on pedagogical strategies for integrating mathematics into undergraduate biology education. The NWHI is one of the few remaining large, mainly intact, predator-dominated coral reef ecosystems and one of the world's largest marine protected areas. Previous bivalve studies focused on the black-lipped pearl oyster, Pinctada margaritifera, which was heavily harvested in the late 1920s, has not recovered, and is now a candidate species for restoration. First, I combined remote sensing, geographic information systems, SCUBA, and mathematical modeling to quantify the abundance, spatial distributions, and filtration capacity of large epifaunal bivalves at Midway Atoll. These bivalves are most abundant on the forereef outside the atoll, but densities are much lower than reported on other reefs, and Midway's bivalves are unlikely to affect plankton abundance and productivity inside the lagoon. Second, I used molecular techniques and phylogenetic reconstructions to identify pearl oysters (Pinctada) from Midway Atoll as P. maculata , a species not previously reported in Hawaii. As a small morphologically cryptic species, P. maculata may be a native species that has not been collected previously, a native species that has been identified incorrectly as the morphologically similar P. radiata, or it may be a recent introduction or natural range extension from the western Pacific. Finally, I review science education literature integrating mathematics into undergraduate biology curricula, and then present and evaluate a

  1. A novel neonatal Michelin Tire Baby Syndrome with craniosynostosis and gigantism

    Directory of Open Access Journals (Sweden)

    Ižbrahim Akalin

    2014-03-01

    Full Text Available     Michelin Tire Baby Syndrome is a rare congenital disorder and characterized clinically well defined multiple ring shaped skin creases. Our patient was born to onconsanguineous healthy parents as the third child of the family at 40 weeks of uneventful gestation with distinctive skin creases and gigantism. He was 4,950 g in weight (>90 percentile, 57.5 cm in length (>90 percentile, and had a head circumferences of 39.5 cm (>90 percentile at birth. The physical examination showed a rough face, brachicephaly and craniosynostosis. His vital and laboratory findings were within normal limits at birth. Cranial and renal ultrasonograms, Xray graphics and cytogenetic analyses were normal. Echocardiography revealed small patent ductus arteriosis and patent foramen ovale. In this report, we present a new case of Michelin Tire Baby Syndrome who is the first neonate associated with severe gigantism and craniosynostosis, in the literature. A review of the related literature has also been presented.

  2. Pegvisomant treatment in gigantism caused by a growth hormone-secreting giant pituitary adenoma.

    Science.gov (United States)

    Müssig, K; Gallwitz, B; Honegger, J; Strasburger, C J; Bidlingmaier, M; Machicao, F; Bornemann, A; Ranke, M B; Häring, H-U; Petersenn, S

    2007-03-01

    Gigantism is rare with the majority of cases caused by a growth hormone (GH)-secreting pituitary adenoma. Treatment options for GH-secreting pituitary adenomas have been widened with the availability of long-acting dopamine agonists, depot preparations of somatostatin analogues, and recently the GH receptor antagonist pegvisomant. A 23-year-old male patient presented with continuous increase in height during the past 6 years due to a GH-secreting giant pituitary adenoma. Because of major intracranial extension and failure of octreotide treatment to shrink the tumour, the tumour was partially resected by a trans-frontal surgical approach. At immunohistochemistry, the tumour showed a marked expression of GH and a sparsely focal expression of prolactin. Somatostatin receptors (sst) 1-5 were not detected. Tumour tissue weakly expressed dopamine receptor type 2. The Gs alpha subunit was intact. Conversion from somatostatin analogue to pegvisomant normalized insulin-like-growth-factor-I (IGF-I) levels and markedly improved glucose tolerance. Pegvisomant is a potent treatment option in patients with pituitary gigantism. In patients who do not respond to somatostatin analogues, knowledge of the SST receptor status may shorten the time to initiation of pegvisomant treatment.

  3. Pituitary gigantism presenting with depressive mood disorder and diabetic ketoacidosis in an Asian adolescent.

    Science.gov (United States)

    Kuo, Sheng-Fong; Chuang, Wen-Yu; Ng, Sohching; Chen, Chih-Hung; Chang, Chen-Nen; Chou, Chi-Hsiang; Weng, Wei-Chieh; Yeh, Chih-Hua; Lin, Jen-Der

    2013-01-01

    Hyperglycemia is seldom described in young patients with pituitary gigantism. Here, we describe the case of a 17-year-old Taiwanese boy who developed depressive mood disorder and diabetic ketoacidosis (DKA) at the presentation of pituitary gigantism. The boy complained of lethargy and dysphoric mood in June 2008. He presented at the emergency department with epigastralgia and dyspnea in January 2009. Results of laboratory tests suggested type 1 diabetes mellitus with DKA. However, serum C-peptide level was normal on follow-up. Although he had no obvious features of acral enlargement, a high level of insulin-like growth factor 1 was detected, and a 75 g oral glucose suppression test showed no suppression of serum growth hormone levels. A pituitary macroadenoma was found on subsequent magnetic resonance imaging. The pituitary adenoma was surgically removed, followed by gamma-knife radiosurgery, and Sandostatin long-acting release treatment. He was then administered metformin, 500 mg twice daily, and to date, his serum glycohemoglobin has been <7%.

  4. Long-term effects of octreotide on pituitary gigantism: its analgesic action on cluster headache.

    Science.gov (United States)

    Otsuka, Fumio; Mizobuchi, Satoshi; Ogura, Toshio; Sato, Kenji; Yokoyama, Masataka; Makino, Hirofumi

    2004-10-01

    We report the case of 19-year-old man with pituitary gigantism due to growth hormone-producing pituitary macroadenoma. The patient complained of recurrent headache and excessive growth spurt since age 15. Octreotide administration was initiated following transsphenoidal pituitary adenomectomy. Octreotide injection for 4 years efficaciously reduced the size of remnant adenoma as well as serum growth hormone levels. Notably, octreotide exhibited a potent analgesic effect on his intractable cluster headache that has continued even after reduction of the adenoma volume. The analgesic effect lasted 2 to 6 hours after each injection and no tachyphylaxis to octreotide appeared during 4-year treatment. To characterize the headache and the pain intensity, analgesic drugs including octreotide, lidocaine, morphine and thiopental were tested using a visual analogue scale (VAS) evaluation, with the result that octreotide exhibited a prompt and complete disappearance of the headache. Headache relief was in part reproduced by morphine injection (56% reduction) but not by lidocaine or thiopental. The present case suggests that the intractable headache associated with pituitary gigantism is possibly related to the endogenous opioid system. Thus, the headache control by octreotide is clinically helpful for continuation of the self-injection regimen.

  5. Are sick individuals weak competitors? Competitive ability of snails parasitized by a gigantism-inducing trematode.

    Directory of Open Access Journals (Sweden)

    Otto Seppälä

    Full Text Available Parasitized individuals are often expected to be poor competitors because they are weakened by infections. Many trematode species, however, although extensively exploiting their mollusc hosts, also induce gigantism (increased host size by diverting host resources towards growth instead of reproduction. In such systems, alternatively to reduced competitive ability due to negative effects of parasitism on host performance, larger size could allow more efficient resource acquisition and thus increase the relative competitive ability of host individuals. We addressed this hypothesis by testing the effect of a trematode parasite Diplostomum pseudospathaceum on the competitive ability of its snail host Lymnaea stagnalis. We experimentally examined the growth of snails kept in pairs in relation to their infection status and intensity of resource competition (i.e. food availability. We found that parasitized snails grew faster and their reproduction was reduced compared to unparasitized individuals indicating parasite-induced gigantism. However, growth of the snails was faster when competing with parasitized individuals compared to unparasitized snails indicating reduced competitive ability due to parasitism. The latter effect, however, was relatively weak suggesting that the effects of the parasite on snail physiology may partly override each other in determining competitive ability.

  6. Gigantic negative magnetoresistance in the bulk of a disordered topological insulator

    Science.gov (United States)

    Breunig, Oliver; Wang, Zhiwei; Taskin, A. A.; Lux, Jonathan; Rosch, Achim; Ando, Yoichi

    2017-05-01

    With the recent discovery of Weyl semimetals, the phenomenon of negative magnetoresistance (MR) is attracting renewed interest. Large negative MR is usually related to magnetism, but the chiral anomaly in Weyl semimetals is a rare exception. Here we report a mechanism for large negative MR which is also unrelated to magnetism but is related to disorder. In the nearly bulk-insulating topological insulator TlBi0.15Sb0.85Te2, we observed gigantic negative MR reaching 98% in 14 T at 10 K, which is unprecedented in a nonmagnetic system. Supported by numerical simulations, we argue that this phenomenon is likely due to the Zeeman effect on a barely percolating current path formed in the disordered bulk. Since disorder can also lead to non-saturating linear MR in Ag2+δSe, the present finding suggests that disorder engineering in narrow-gap systems is useful for realizing gigantic MR in both positive and negative directions.

  7. Gigantic negative magnetoresistance in the bulk of a disordered topological insulator

    Science.gov (United States)

    Breunig, Oliver; Wang, Zhiwei; Taskin, A A; Lux, Jonathan; Rosch, Achim; Ando, Yoichi

    2017-01-01

    With the recent discovery of Weyl semimetals, the phenomenon of negative magnetoresistance (MR) is attracting renewed interest. Large negative MR is usually related to magnetism, but the chiral anomaly in Weyl semimetals is a rare exception. Here we report a mechanism for large negative MR which is also unrelated to magnetism but is related to disorder. In the nearly bulk-insulating topological insulator TlBi0.15Sb0.85Te2, we observed gigantic negative MR reaching 98% in 14 T at 10 K, which is unprecedented in a nonmagnetic system. Supported by numerical simulations, we argue that this phenomenon is likely due to the Zeeman effect on a barely percolating current path formed in the disordered bulk. Since disorder can also lead to non-saturating linear MR in Ag2+δSe, the present finding suggests that disorder engineering in narrow-gap systems is useful for realizing gigantic MR in both positive and negative directions. PMID:28541291

  8. Sodium provides unique insights into transgenerational effects of ocean acidification on bivalve shell formation.

    Science.gov (United States)

    Zhao, Liqiang; Schöne, Bernd R; Mertz-Kraus, Regina; Yang, Feng

    2017-01-15

    Ocean acidification is likely to have profound impacts on marine bivalves, especially on their early life stages. Therefore, it is imperative to know whether and to what extent bivalves will be able to acclimate or adapt to an acidifying ocean over multiple generations. Here, we show that reduced seawater pH projected for the end of this century (i.e., pH7.7) led to a significant decrease of shell production of newly settled juvenile Manila clams, Ruditapes philippinarum. However, juveniles from parents exposed to low pH grew significantly faster than those from parents grown at ambient pH, exhibiting a rapid transgenerational acclimation to an acidic environment. The sodium composition of the shells may shed new light on the mechanisms responsible for beneficial transgenerational acclimation. Irrespective of parental exposure, the amount of Na incorporated into shells increased with decreasing pH, implying active removal of excessive protons through the Na + /H + exchanger which is known to depend on the Na + gradient actively built up by the Na + /K + -ATPase as a driving force. However, the shells with a prior history of transgenerational exposure to low pH recorded significantly lower amounts of Na than those with no history of acidic exposure. It therefore seems very likely that the clams may implement less costly and more ATP-efficient ion regulatory mechanisms to maintain pH homeostasis in the calcifying fluid following transgenerational acclimation. Our results suggest that marine bivalves may have a greater capacity to acclimate or adapt to ocean acidification by the end of this century than currently understood. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Characterizing Photosymbiosis Between Fraginae Bivalves and Symbiodinium Using Phylogenetics and Stable Isotopes

    Directory of Open Access Journals (Sweden)

    Jingchun Li

    2018-04-01

    Full Text Available Photosymbiotic associations between heterotrophic hosts and photosynthetic algae play crucial roles in maintaining the trophic and structural integrity of coral reef ecosystems. The marine bivalve subfamily Fraginae contains both non-symbiotic and photosymbiotic lineages, making it an ideal comparative system to study the origin and evolutionary adaptations of photosymbiosis. The symbiotic species exhibit unique morphological adaptations to photosymbiosis. However, the basic biology of these photosymbiotic relationships, such as symbiont diversity and nutritional benefits, has not been thoroughly characterized. In this study, we examined the general morphology of four Fraginae species occupying different depths (0–10 m: Corculum cardissa, Fragum fragum, Fragum scruposum, and Fragum sueziense. Abundant symbionts were found in the mantle, gill, and part of the foot, contained in tubular networks within host tissues. We used molecular phylogenetics to investigate the algal symbiont community of these Fraginae species. Results showed that symbionts from all four species are dinoflagellates belonging to the Symbiodinium clade C and we did not detect any host-specific or geographic-specific genetic structures within the symbionts. We also used stable carbon isotope analyses to examine whether the cockles are directly utilizing photosynthetically derived carbon sources. All species show less depleted 13C compared to filter-feeding bivalves, suggesting at least part of their organic carbon is derived directly from the symbionts. However, 13C depletion of Fragum sueziense collected from deeper habitats are less distinguishable from filter-feeding bivalves. This indicates that species in deeper habitats may rely less on photosymbiosis due to the reduced light availability. Given that the symbiotic fragines exhibit varying morphologies, habitats, and utilization of symbiont photosynthesis, the subfamily represents an ideal model system to study

  10. Cardiac and metabolic effects of chronic growth hormone and insulin-like growth factor I excess in young adults with pituitary gigantism.

    Science.gov (United States)

    Bondanelli, Marta; Bonadonna, Stefania; Ambrosio, Maria Rosaria; Doga, Mauro; Gola, Monica; Onofri, Alessandro; Zatelli, Maria Chiara; Giustina, Andrea; degli Uberti, Ettore C

    2005-09-01

    Chronic growth hormone (GH)/insulin-like growth factor I (IGF-I) excess is associated with considerable mortality in acromegaly, but no data are available in pituitary gigantism. The aim of the study was to evaluate the long-term effects of early exposure to GH and IGF-I excess on cardiovascular and metabolic parameters in adult patients with pituitary gigantism. Six adult male patients with newly diagnosed gigantism due to GH secreting pituitary adenoma were studied and compared with 6 age- and sex-matched patients with acromegaly and 10 healthy subjects. Morphologic and functional cardiac parameters were evaluated by Doppler echocardiography. Glucose metabolism was assessed by evaluating glucose tolerance and homeostasis model assessment index. Disease duration was significantly longer (Pgigantism than in patients with acromegaly, whereas GH and IGF-I concentrations were comparable. Left ventricular mass was increased both in patients with gigantism and in patients with acromegaly, as compared with controls. Left ventricular hypertrophy was detected in 2 of 6 of both patients with gigantism and patients with acromegaly, and isolated intraventricular septum thickening in 1 patient with gigantism. Inadequate diastolic filling (ratio between early and late transmitral flow velocitygigantism and 1 of 6 patients with acromegaly. Impaired glucose metabolism occurrence was higher in patients with acromegaly (66%) compared with patients with gigantism (16%). Concentrations of IGF-I were significantly (Pgigantism who have cardiac abnormalities than in those without cardiac abnormalities. In conclusion, our data suggest that GH/IGF-I excess in young adult patients is associated with morphologic and functional cardiac abnormalities that are similar in patients with gigantism and in patients with acromegaly, whereas occurrence of impaired glucose metabolism appears to be higher in patients with acromegaly, although patients with gigantism are exposed to GH excess for a

  11. Physiological effects of hypercapnia in the deep-sea bivalve Acesta excavata (Fabricius, 1779) (Bivalvia; Limidae)

    DEFF Research Database (Denmark)

    Hammer, Karen M.; Kristiansen, Erlend; Zachariassen, Karl Erik

    2011-01-01

    The option of storing CO(2) in subsea rock formations to mitigate future increases in atmospheric CO(2) may induce problems for animals in the deep sea. In the present study the deep-sea bivalve Acesta excavata was subjected to environmental hypercapnia (pHSW 6.35, P(CO2), =33,000 mu atm...... extracellular pH remained significantly lower during recovery. Intracellular non-bicarbonate buffering capacity of the posterior adductor muscle of hypercapnic animals was significantly lower than control values, but this was not the case for the remaining tissues analyzed. Oxygen consumption initially dropped...

  12. Comparative sensitivity of European native (Anodonta anatina) and exotic (Corbicula fluminea) bivalves to mercury

    Science.gov (United States)

    Oliveira, Patrícia; Lopes-Lima, Manuel; Machado, Jorge; Guilhermino, Lúcia

    2015-12-01

    Pollution is believed to be an important factor modulating the competition between exotic invasive bivalves and their native competitors. Thus, the objective of the present study was to compare the sensitivity of the European native Anodonta anatina and the exotic invasive species Corbicula fluminea to mercury, a ubiquitous environmental contaminant of high concern. In laboratory acute bioassays, adult organisms of both species were exposed independently to mercury for 96 h (31-500 μg/L). The criteria indicative of toxicity were mortality and biomarkers of oxidative stress and damage, neurotoxicity, and energy production changes. Mercury induced mortality in A. anatina (72 h-LC10 and 72 h-LC50 of 14.0 μg/L and 49.6 μg/L, respectively) but not in C. fluminea. The ability of C. fluminea to maintaining the shell closed for considerable periods of time when exposed to high concentrations of mercury and the effective activation (up to 63 μg/L) of mechanisms against the oxidative stress caused by mercury may have contributed to its relatively low sensitivity. In the range of concentrations tested, mercury had no significant effects on the other parameters analysed in C. fluminea. Overall, the findings of the present study, suggest that in real scenarios of competition between C. fluminea and A. anatina populations, the presence of mercury may modulate the process, acting in favour of the exotic species because it is less sensitive to this environmental contaminant than the native bivalve. The results of the present study highlight the need of further investigation on the effects of mercury on the competition between exotic invasive species and their native competitors, especially the effects potentially induced by long-term exposure to low concentrations of this metal, the mechanisms involved in the tolerance to mercury-induced stress, and the potential post-exposure recovery of both exotic invasive and native bivalves. This knowledge is most important for

  13. Trace element determination in soft tissues of marine bivalves by activation analysis

    International Nuclear Information System (INIS)

    Fukushima, M.; Tamate, H.; Nakano, Y.

    2003-01-01

    Trace elements in soft tissues of marine bivalves were determined by neutron activation analysis (NAA) and photon activation analysis (PAA). Elemental levels of Ag, As, Br, Co, Cu, Fe, I, Mn, Ni, Rb, Se, and Zn in the organs of giant ezoscallos, rock oysters, and giant crams were obtained. The metal-bound proteins were extracted from the mantles and hepatopancreases of rock oysters. By irradiating the fraction obtained by HPLC gel chromatography, the possibility for the existence of an Ag bound protein in the mantles was found. (author)

  14. [Nutrition and biological value of food parts of a trade bivalve mollusk Anadara broughtoni].

    Science.gov (United States)

    Tabakaeva, O V; Tabakaev, A V

    2015-01-01

    Currently, the human diet includes different new products of seafishing, including non-fish--bivalves and gastropods, holothurias, echinoderms, jellyfishes that demands careful studying of their chemical composition. The purpose of the study was to determine the nutritional and biological value of all soft parts of the burrowing bivalve MOLLUSK Anadara broughtoni from the Far East region. It was established thatfood parts of a bivalve were significantly flooded (water content--73.5-84.2%), with the minimum water content in the adductor and maximum in the mantle. Dry solids are presented by organic (89-93%) and mineral (7-11%) components. Organic components consist of protein (14.6-20.7%), lipids (1.8-2.3%), carbohydrates (2.1-2.6%). The analysis of amino-acid composition of proteins of food parts of the mollusk of Anadara broughtonishowed the presence of all essential amino acids with slight differences in their content depending on the localization of the protein. All edible parts have tryptophan as the limiting amino acid. Muscle proteins have maximum level of lysine, methionine, cysteine, phenylalanine and tyrosine; mantle proteins--leucine, isoleucine and threonine; adductor proteins--valine, phenylalanine, tyrosine, methionine and cysteine. Predominant nonessential amino acids forproteins of all food pieces are glycine, aspartic acid, glutamic acid, arginine. The coefficient of amino-acid score differences of adductor protein (31.7%) is less than the same of cloak by 3.7%. The indicator "biological value" is maximal for adductor (68.3%), but the differenceformuscle is only 0.83%. Mantle proteins are characterized by minimum biological value (64.6%). The coefficient of utility of amino acid composition of protein is maximalfor muscle (57.83%), and values for a cloak and an adductor differ slightly (55.81 and 55.96%). Taurine content in food parts of a mollusk Anadara broughtoni is rather high compared to with other bivalve mollusks of the Far East region

  15. Soundscapes and Larval Settlement: Larval Bivalve Responses to Habitat-Associated Underwater Sounds.

    Science.gov (United States)

    Eggleston, David B; Lillis, Ashlee; Bohnenstiehl, DelWayne R

    2016-01-01

    We quantified the effects of habitat-associated sounds on the settlement response of two species of bivalves with contrasting habitat preferences: (1) Crassostrea virginicia (oyster), which prefers to settle on other oysters, and (2) Mercenaria mercenaria (clam), which settles on unstructured habitats. Oyster larval settlement in the laboratory was significantly higher when exposed to oyster reef sound compared with either off-reef or no-sound treatments. Clam larval settlement did not vary according to sound treatments. Similar to laboratory results, field experiments showed that oyster larval settlement in "larval housings" suspended above oyster reefs was significantly higher compared with off-reef sites.

  16. Estimation of food limitation of bivalve larvae in coastal waters of north-western Europe

    DEFF Research Database (Denmark)

    Bos, O.G.; Hendriks, I.E.; Strasser, M.

    2006-01-01

    Marine invertebrate recruitment may be affected by food limitation during the pelagic larval life stages. In the present study, field data on abundance of bivalve larvae along with their prey (small phytoplankton) were examined to see whether they were consistent with predictions made...... assimilation rate averaged 7-26% of the maximum assimilation rate. Under the assumptions made for the present study, it is suggested that growth of larvae in north-west European waters is often food-limited. (c) 2005 Elsevier B.V. All rights reserved...

  17. Evaluation of γ-radiation-induced DNA damage in two species of bivalves and their relative sensitivity using comet assay

    International Nuclear Information System (INIS)

    Praveen Kumar, M.K.; Shyama, S.K.; Sonaye, B.S.; Naik, U Roshini; Kadam, S.B.; Bipin, P.D.; D’costa, A.; Chaubey, R.C.

    2014-01-01

    Highlights: • Possible genotoxic effect of accidental exposure of aquatic fauna to γ radiation. • Relative sensitivity of bivalves to γ radiation is also analyzed using comet assay. • γ radiation induced significant genetic damage in both the species of bivalves. • P. malabarica and M. casta exhibited a similar level of sensitivity to γ radiation. • Comet assay may be used as a biomarker for the environmental biomonitoring. - Abstract: Ionizing radiation is known to induce genetic damage in diverse groups of organisms. Under accidental situations, large quantities of radioactive elements get released into the environment and radiation emitted from these radionuclides may adversely affect both the man and the non-human biota. The present study is aimed (a) to know the genotoxic effect of gamma radiation on aquatic fauna employing two species of selected bivalves, (b) to evaluate the possible use of ‘Comet assay’ for detecting genetic damage in haemocytes of bivalves as a biomarker for environmental biomonitoring and also (c) to compare the relative sensitivity of two species of bivalves viz. Paphia malabarica and Meretrix casta to gamma radiation. The comet assays was optimized and validated using different concentrations (18, 32 and 56 mg/L) of ethyl methanesulfonate (EMS), a direct-acting reference genotoxic agent, to which the bivalves were exposed for various times (24, 48 and 72 h). Bivalves were irradiated (single acute exposure) with 5 different doses (viz. 2, 4, 6, 8 and 10 Gy) of gamma radiation and their genotoxic effects on the haemocytes were studied using the comet assay. Haemolymph was collected from the adductor muscle at 24, 48 and 72 h of both EMS-exposed and irradiated bivalves and comet assay was carried out using standard protocol. A significant increase in DNA damage was observed as indicated by an increase in % tail DNA damage at different concentrations of EMS and all the doses of gamma radiation as compared to controls in

  18. Evaluation of γ-radiation-induced DNA damage in two species of bivalves and their relative sensitivity using comet assay

    Energy Technology Data Exchange (ETDEWEB)

    Praveen Kumar, M.K., E-mail: here.praveen@gmail.com [Department of Zoology, Goa University, Goa 403206 (India); Shyama, S.K., E-mail: skshyama@gmail.com [Department of Zoology, Goa University, Goa 403206 (India); Sonaye, B.S. [Department of Radiation Oncology, Goa Medical College, Goa (India); Naik, U Roshini; Kadam, S.B.; Bipin, P.D.; D’costa, A. [Department of Zoology, Goa University, Goa 403206 (India); Chaubey, R.C. [Radiation Biology and Health Science Division, Bhabha Atomic Research Centre, Mumbai (India)

    2014-05-01

    Highlights: • Possible genotoxic effect of accidental exposure of aquatic fauna to γ radiation. • Relative sensitivity of bivalves to γ radiation is also analyzed using comet assay. • γ radiation induced significant genetic damage in both the species of bivalves. • P. malabarica and M. casta exhibited a similar level of sensitivity to γ radiation. • Comet assay may be used as a biomarker for the environmental biomonitoring. - Abstract: Ionizing radiation is known to induce genetic damage in diverse groups of organisms. Under accidental situations, large quantities of radioactive elements get released into the environment and radiation emitted from these radionuclides may adversely affect both the man and the non-human biota. The present study is aimed (a) to know the genotoxic effect of gamma radiation on aquatic fauna employing two species of selected bivalves, (b) to evaluate the possible use of ‘Comet assay’ for detecting genetic damage in haemocytes of bivalves as a biomarker for environmental biomonitoring and also (c) to compare the relative sensitivity of two species of bivalves viz. Paphia malabarica and Meretrix casta to gamma radiation. The comet assays was optimized and validated using different concentrations (18, 32 and 56 mg/L) of ethyl methanesulfonate (EMS), a direct-acting reference genotoxic agent, to which the bivalves were exposed for various times (24, 48 and 72 h). Bivalves were irradiated (single acute exposure) with 5 different doses (viz. 2, 4, 6, 8 and 10 Gy) of gamma radiation and their genotoxic effects on the haemocytes were studied using the comet assay. Haemolymph was collected from the adductor muscle at 24, 48 and 72 h of both EMS-exposed and irradiated bivalves and comet assay was carried out using standard protocol. A significant increase in DNA damage was observed as indicated by an increase in % tail DNA damage at different concentrations of EMS and all the doses of gamma radiation as compared to controls in

  19. Influence of food on the assimilation of selected metals in tropical bivalves from the New Caledonia lagoon: Qualitative and quantitative aspects

    International Nuclear Information System (INIS)

    Hedouin, Laetitia; Metian, Marc; Lacoue-Labarthe, Thomas; Fichez, Renaud; Teyssie, Jean-Louis; Bustamante, Paco; Warnau, Michel

    2010-01-01

    The present study aimed at examining the influence of food quality and quantity on the assimilation efficiency (AE) of metals in two abundant bivalves in the New Caledonia lagoon, the oyster Isognomon isognomon and the clam Gafrarium tumidum. Bivalves were exposed via their food to the radiotracers of three metals of concern in New Caledonia ( 54 Mn, 57 Co and 65 Zn) under different feeding conditions (phytoplankton species, cell density, and cell-associated metal concentration). When bivalves were fed Heterocapsa triquetra, Emiliania huxleyi and Isochrysis galbana, AE of Mn, Co and Zn was strongly influenced by the phytoplankton species and by the metal considered. In contrast, when fed one given phytoplankton species previously exposed to different concentrations of Co, phytoplankton-associated Co load had no influence on the AE and on the retention time of the metal in both bivalves. Metals ingested with I. galbana displayed generally the highest AE in both bivalve species, except for Mn in clams for which the highest AE was observed for H. triquetra. Influence of food quantity was investigated by exposing bivalves to different cell densities of I. galbana (5 x 10 3 , 10 4 or 5 x 10 4 cell ml -1 ). As for food quality, food quantity was found to influence AE of Mn, Co and Zn, the highest AE being observed when bivalves were fed the lowest cell density. Overall, results indicate that the two bivalve species are able to adjust their feeding strategies according to the food conditions prevailing in their environment.

  20. Feeding current characteristics of three morphologically different bivalve suspension feeders, Crassostrea gigas, Mytilus edulis and Cerastoderma edule, in relation to food competition

    NARCIS (Netherlands)

    Troost, K.; Stamhuis, E.J.; van Duren, L.A; Wolff, W.J.

    Introduced Pacific oysters (Crassostrea gigas) have shown rapid expansion in the Oosterschelde estuary, while stocks of native bivalves declined slightly or remained stable. This indicates that they might have an advantage over native bivalve filter feeders. Hence, at the scale of individual

  1. Feeding current characteristics of three morphologically different bivalve suspension feeders, Crassostrea gigas Mytilus edulis and Cerastoderma edule , in relation to food competition

    NARCIS (Netherlands)

    Troost, K.; Stamhuis, E.J.; Duren, L.A.; Wolff, W.

    2009-01-01

    Introduced Pacific oysters (Crassostrea gigas) have shown rapid expansion in the Oosterschelde estuary, while stocks of native bivalves declined slightly or remained stable. This indicates that they might have an advantage over native bivalve filter feeders. Hence, at the scale of individual

  2. Adaptive morphologies and guild structure in a high-diversity bivalve fauna from an early Campanian rocky shore, Ivö Klack (Sweden)

    DEFF Research Database (Denmark)

    Sørensen, Anne Mehlin; Surlyk, Finn; Jagt, John W. M.

    2012-01-01

    habitats. Study of the functional morphology of bivalve shells and comparison with extant relatives has resulted in a subdivision of the fauna into seven guilds and five habitats. The bivalve fauna represents a withinhabitat, time-averaged assemblage to which none of the species was introduced from...

  3. Deciphering the link between doubly uniparental inheritance of mtDNA and sex determination in bivalves: Clues from comparative transcriptomics

    Science.gov (United States)

    Capt, Charlotte; Renaut, Sébastien; Ghiselli, Fabrizio; Milani, Liliana; Johnson, Nathan A.; Sietman, Bernard E.; Stewart, Donald; Breton, Sophie

    2018-01-01

    Bivalves exhibit an astonishing diversity of sexual systems and sex-determining mechanisms. They can be gonochoric, hermaphroditic or androgenetic, with both genetic and environmental factors known to determine or influence sex. One unique sex-determining system involving the mitochondrial genome has also been hypothesized to exist in bivalves with doubly uniparental inheritance (DUI) of mtDNA. However, the link between DUI and sex determination remains obscure. In this study, we performed a comparative gonad transcriptomics analysis for two DUI-possessing freshwater mussel species to better understand the mechanisms underlying sex determination and DUI in these bivalves. We used a BLAST reciprocal analysis to identify orthologs between Venustaconcha ellipsiformis and Utterbackia peninsularis and compared our results with previously published sex-specific bivalve transcriptomes to identify conserved sex-determining genes. We also compared our data with other DUI species to identify candidate genes possibly involved in the regulation of DUI. A total of ∼12,000 orthologous relationships were found, with 2,583 genes differentially expressed in both species. Among these genes, key sex-determining factors previously reported in vertebrates and in bivalves (e.g., Sry, Dmrt1, Foxl2) were identified, suggesting that some steps of the sex-determination pathway may be deeply conserved in metazoans. Our results also support the hypothesis that a modified ubiquitination mechanism could be responsible for the retention of the paternal mtDNA in male bivalves, and revealed that DNA methylation could also be involved in the regulation of DUI. Globally, our results suggest that sets of genes associated with sex determination and DUI are similar in distantly-related DUI species.

  4. Granuloma central de células gigantes Giant cells central granuloma

    Directory of Open Access Journals (Sweden)

    Ayelén María Portelles Massó

    2011-03-01

    Full Text Available El granuloma reparativo central de células gigantes es una lesión proliferativa no neoplásica de etiología desconocida. Se presenta un paciente masculino de 40 años de edad, portador de prótesis parcial superior. Fue remitido al Servicio de Cirugía Maxilofacial del Hospital "V. I. Lenin" por presentar aumento de volumen en reborde alveolar superior, de color rojo grisáceo y que provocaba expansión de corticales óseas. Una vez analizados los exámenes clínicos, radiográficos e histopatológicos se diagnosticó un granuloma reparativo central de células gigantes Se realizó exéresis quirúrgica de la lesión y extracción de dientes adyacentes con una evolución satisfactoria sin señales de recidivas luego de tres años del tratamiento. El granuloma reparativo central de células gigantes se presentó como respuesta a un trauma. La correcta interpretación de los datos clínicos, radiográficos e histopatológicos nos permitió llegar al correcto diagnóstico y plan de tratamiento.Giant-cell central reparative granuloma is non neoplastic proliferative lesion of unknown etiology. We report a 40 years old male patient who was admitted at the Maxillofacial Service of the "V. I. Lenin" Hospital. The patient had partial upper prosthesis and was complaining of red-grey volume increase lesion in upper alveolar ridge which led to the expansion of cortical bone. Having analyzed clinical, radiographic and histopathological findings the case was concluded as a giant-cell central reparative granuloma. Surgical exeresis and adjunct tooth extraction were done. After three years of treatment, satisfactory follow up without recurrence is reported.

  5. Field clearance of an intertidal bivalve bed: relative significance of the co-occurring blue mussel Mytilus edulis and Pacific oyster Crassostrea gigas

    DEFF Research Database (Denmark)

    Vismann, Bent; Holm, Mark Wejlemann; Davids, Jens

    2016-01-01

    was estimated by combining field measurements of clearance rates and modelling of the bivalve bed (topography, biomass distribution, temporal and spatial water coverage and depth). The average density of C. gigas and M. edulis was 35 ± 36 and 1001 ± 685 ind. m−2, respectively. The water volume cleared during...... a tidal cycle was estimated at 45 838 m3, of which C. gigas and M. edulis contributed 9169 and 36 669 m3, respectively. Therefore, M. edulis contributed 4 times as much as C. gigas to the bivalve bed’s clearance, and the 2 bivalves were estimated to clear the water volume 1.9 times during each tidal cycle....... However, the estimated water column cleared during low tide is overestimated due to phytoplankton depletion. Hence, it is concluded that the bivalve bed clears the water close to 1 time each tidal cycle. This, together with a low dry weight of soft parts, indicates that the bivalve bed, in general...

  6. Familial gigantism

    NARCIS (Netherlands)

    W.W. de Herder (Wouter)

    2012-01-01

    textabstractFamilial GH-secreting tumors are seen in association with three separate hereditary clinical syndromes: multiple endocrine neoplasia type 1, Carney complex, and familial isolated pituitary adenomas.

  7. Familial gigantism

    Directory of Open Access Journals (Sweden)

    Wouter W. de Herder

    2012-01-01

    Full Text Available Familial GH-secreting tumors are seen in association with three separate hereditary clinical syndromes: multiple endocrine neoplasia type 1, Carney complex, and familial isolated pituitary adenomas.

  8. A Gigantic, Exceptionally Complete Titanosaurian Sauropod Dinosaur from Southern Patagonia, Argentina

    Science.gov (United States)

    Lacovara, Kenneth J.; Lamanna, Matthew C.; Ibiricu, Lucio M.; Poole, Jason C.; Schroeter, Elena R.; Ullmann, Paul V.; Voegele, Kristyn K.; Boles, Zachary M.; Carter, Aja M.; Fowler, Emma K.; Egerton, Victoria M.; Moyer, Alison E.; Coughenour, Christopher L.; Schein, Jason P.; Harris, Jerald D.; Martínez, Rubén D.; Novas, Fernando E.

    2014-01-01

    Titanosaurian sauropod dinosaurs were the most diverse and abundant large-bodied herbivores in the southern continents during the final 30 million years of the Mesozoic Era. Several titanosaur species are regarded as the most massive land-living animals yet discovered; nevertheless, nearly all of these giant titanosaurs are known only from very incomplete fossils, hindering a detailed understanding of their anatomy. Here we describe a new and gigantic titanosaur, Dreadnoughtus schrani, from Upper Cretaceous sediments in southern Patagonia, Argentina. Represented by approximately 70% of the postcranial skeleton, plus craniodental remains, Dreadnoughtus is the most complete giant titanosaur yet discovered, and provides new insight into the morphology and evolutionary history of these colossal animals. Furthermore, despite its estimated mass of about 59.3 metric tons, the bone histology of the Dreadnoughtus type specimen reveals that this individual was still growing at the time of death. PMID:25186586

  9. Gate-tunable gigantic lattice deformation in VO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Okuyama, D., E-mail: okuyama@riken.jp, E-mail: nakano@imr.tohoku.ac.jp, E-mail: iwasa@ap.t.u-tokyo.ac.jp; Hatano, T. [RIKEN Center for Emergent Matter Science (CEMS), Wako 351-0198 (Japan); Nakano, M., E-mail: okuyama@riken.jp, E-mail: nakano@imr.tohoku.ac.jp, E-mail: iwasa@ap.t.u-tokyo.ac.jp [RIKEN Center for Emergent Matter Science (CEMS), Wako 351-0198 (Japan); Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Takeshita, S.; Ohsumi, H.; Tardif, S. [RIKEN SPring-8 Center, Hyogo 679-5148 (Japan); Shibuya, K. [National Institute of Advanced Industrial Science and Technology, Tsukuba 305-8562 (Japan); Yumoto, H.; Koyama, T.; Ohashi, H. [Japan Synchrotron Radiation Research Institute, SPring-8, Hyogo 679-5198 (Japan); Takata, M. [RIKEN SPring-8 Center, Hyogo 679-5148 (Japan); Japan Synchrotron Radiation Research Institute, SPring-8, Hyogo 679-5198 (Japan); Kawasaki, M.; Tokura, Y.; Iwasa, Y., E-mail: okuyama@riken.jp, E-mail: nakano@imr.tohoku.ac.jp, E-mail: iwasa@ap.t.u-tokyo.ac.jp [RIKEN Center for Emergent Matter Science (CEMS), Wako 351-0198 (Japan); Quantum-Phase Electronics Center and Department of Applied Physics, University of Tokyo, Tokyo 113-8656 (Japan); Arima, T. [RIKEN Center for Emergent Matter Science (CEMS), Wako 351-0198 (Japan); RIKEN SPring-8 Center, Hyogo 679-5148 (Japan); Department of Advanced Materials Science, University of Tokyo, Kashiwa 277-8561 (Japan)

    2014-01-13

    We examined the impact of electric field on crystal lattice of vanadium dioxide (VO{sub 2}) in a field-effect transistor geometry by in-situ synchrotron x-ray diffraction measurements. Whereas the c-axis lattice parameter of VO{sub 2} decreases through the thermally induced insulator-to-metal phase transition, the gate-induced metallization was found to result in a significant increase of the c-axis length by almost 1% from that of the thermally stabilized insulating state. We also found that this gate-induced gigantic lattice deformation occurs even at the thermally stabilized metallic state, enabling dynamic control of c-axis lattice parameter by more than 1% at room temperature.

  10. Escleritis nodular posterior gigante compatible con sarcoidosis ocular simulando un melanoma de la coroides

    OpenAIRE

    Pérez-Campagne, E.; Guex-Crosier, Y.; Schalenbourg, A.; Uffer, S.; Zografos, L.

    2007-01-01

    Caso clínico: Un paciente de 30 años fue enviado a nuestro servicio oncológico de referencia con el diagnóstico de melanoma amelanótico de la coroides del ojo izquierdo. Se hicieron los siguientes exámenes: oftalmoscopía, angiografía fluoresceínica, angiografía con verde de indocianina, ecografía, resonancia magnética y biopsia. Discusión: El diagnóstico de escleritis nodular posterior gigante basado en la ecografía se confirmó mediante una biopsia. Se realizó un examen médico completo buscán...

  11. Gigantism due to growth hormone excess in a boy with optic glioma.

    Science.gov (United States)

    Drimmie, F M; MacLennan, A C; Nicoll, J A; Simpson, E; McNeill, E; Donaldson, M D

    2000-10-01

    True gigantism is rare in early childhood and is usually due to excess GH secretion from a pituitary adenoma. We report a case in which the endocrine abnormality is secondary to an optic glioma. Careful endocrine evaluation has shown that GH peak amplitude was not increased but rather there was failure of GH levels to suppress to baseline and a lack of pulsatility. There is no evidence of a direct secretory role for the tumour and we postulate that the tumour is affecting GH secretion through an effect on somatostatin tone. Specific tumour therapy is not indicated for this patient in the absence of mass effect or visual disturbance. The GH excess is being treated with somatostatin analogue (Octreotide) and as he has developed precocious puberty he is also receiving long acting GnRH analogue (Zoladex). This boy appears likely to have neurofibromatosis type 1 (NF1) which raises the question of subtle GH excess in NF1 patients with tall stature.

  12. The Perlman syndrome: familial renal dysplasia with Wilms tumor, fetal gigantism and multiple congenital anomalies. 1984.

    Science.gov (United States)

    Neri, Giovanni; Martini-Neri, Maria Enrica; Katz, Ben E; Opitz, John M

    2013-11-01

    The ensuing paper by Professor Giovanni Neri and colleagues was originally published in 1984, American Journal of Medical Genetics 19:195–207. The original article described a new family with a condition that the authors designated as the Perlman syndrome. This disorder, while uncommon, is an important multiple congenital anomaly and dysplasia syndrome; the causative gene was recently identified. This paper is a seminal work and is graciously republished by Wiley-Blackwell in the Special Festschrift issue honoring Professor Neri. We describe a familial syndrome of renal dysplasia, Wilms tumor, hyperplasia of the endocrine pancreas, fetal gigantism, multiple congenital anomalies and mental retardation. This condition was previously described by Perlman et al. [1973, 1975] and we propose to call it the "Perlman syndrome." It appears to be transmitted as an autosomal recessive trait. The possible relationships between dysplasia, neoplasia and malformation are discussed. © 2013 Wiley Periodicals, Inc.

  13. Molecular design of TiO2 for gigantic red shift via sublattice substitution.

    Science.gov (United States)

    Shao, Guosheng; Deng, Quanrong; Wan, Lin; Guo, Meilan; Xia, Xiaohong; Gao, Yun

    2010-11-01

    The effects of 3d transition metal doping in TiO2 phases have been simulated in detail. The results of modelling indicate that Mn has the biggest potential among 3d transition metals, for the reduction of energy gap and the introduction of effective intermediate bands to allow multi-band optical absorption. On the basis of theoretical formulation, we have incorporated considerable amount of Mn in nano-crystalline TiO2 materials. Mn doped samples demonstrate significant red shift in the optical absorption edge, with a secondary absorption edge corresponding to theoretically predicted intermediate bands/states. The gigantic red shift achievable in Mn-doped TiO2 is expected to extend the useful TiO2 functionalities well beyond the UV threshold via the optical absorption of both visible and infrared photon irradiance.

  14. Esplenomegalia gigante en la leucemia linfocítica crónica

    Directory of Open Access Journals (Sweden)

    José Luis González González

    Full Text Available La leucemia linfocítica crónica constituye la forma de leucemia más frecuente en el mundo occidental; sus síntomas más frecuentes son la aparición de adenopatías, el cansancio, la pérdida de peso y aquellos derivados de las infecciones y del síndrome anémico. Aunque es una de las enfermedades que rara vez son tributarias de una esplenectomía por hiperesplenismo, es una entidad frecuente en hematología y debe ser del dominio y conocimiento del cirujano general. Presentamos un paciente con una esplenomegalia de proporciones gigantes, de inusual aparición.

  15. Hepatocarcinoma gigante unifocal en mujer con ingesta prolongada de anticonceptivos hormonales: ¿casualidad o causalidad?

    Directory of Open Access Journals (Sweden)

    VICTOR MANUEL LOPEZ MOURIÑO

    2016-12-01

    Full Text Available Presentamos un caso de una paciente de mediana edad con ingesta mantenida de anticonceptivos hormonales (AH que desarrolla múltiples adenomas hepáticos (asociación bien documentada y un carcinoma hepatocelular (CHC unifocal gigante sin encontrar otros factores de riesgo para el mismo (enolismo, tabaquismo, cirrosis, hemocromatosis,..... Si bien en la literatura no hay unanimidad respecto a la asociación del consumo de AH con el CHC, algunos autores ya contemplaron esa posibilidad, excluyendo también otras etiologías reconocidas de CHC, por lo que debería reevaluarse si su asociación es aleatoria o por el contrario existe nexo causal.

  16. Cordoma Sacrococcígeo gigante: relato de caso Giant Sacrococcygeal chordoma: case report

    Directory of Open Access Journals (Sweden)

    Tiago Leal Ghezzi

    2009-06-01

    Full Text Available Cordoma sacrococcígeo é uma neoplasia maligna rara que se origina de remanescentes da notocorda. A localização crítica, comportamento localmente agressivo, reconhecida resistência à radioterapia, significativa morbimortalidade cirúrgica e elevada taxa de recidiva tornam seu tratamento um desafio. Descrevemos um caso de cordoma sacrococcígeo gigante.Sacrococcygeal chordoma is a rare malignant neoplasm arised from the remmants of the notochord. The critical localization, locally aggressive behavior, well-known resistance to radiation therapy, meaningful surgical morbimortality and increased recurrence rate become its treatment a challenge. We describe a case of a giant unresectable sacrococcygeal chordoma.

  17. Intraspecific competition and high food availability are associated with insular gigantism in a lizard.

    Science.gov (United States)

    Pafilis, Panayiotis; Meiri, Shai; Foufopoulos, Johannes; Valakos, Efstratios

    2009-09-01

    Resource availability, competition, and predation commonly drive body size evolution. We assess the impact of high food availability and the consequent increased intraspecific competition, as expressed by tail injuries and cannibalism, on body size in Skyros wall lizards (Podarcis gaigeae). Lizard populations on islets surrounding Skyros (Aegean Sea) all have fewer predators and competitors than on Skyros but differ in the numbers of nesting seabirds. We predicted the following: (1) the presence of breeding seabirds (providing nutrients) will increase lizard population densities; (2) dense lizard populations will experience stronger intraspecific competition; and (3) such aggression, will be associated with larger average body size. We found a positive correlation between seabird and lizard densities. Cannibalism and tail injuries were considerably higher in dense populations. Increases in cannibalism and tail loss were associated with large body sizes. Adult cannibalism on juveniles may select for rapid growth, fuelled by high food abundance, setting thus the stage for the evolution of gigantism.

  18. Gigantic Dzyaloshinskii-Moriya interaction in the MnBi ultrathin films

    Science.gov (United States)

    Yu, Jie-Xiang; Zang, Jiadong; Zang's Team

    The magnetic skyrmion, a swirling-like spin texture with nontrivial topology, is driven by strong Dzyaloshinskii-Moriya (DM) interaction originated from the spin-orbit coupling in inversion symmetry breaking systems. Here, based on first-principles calculations, we predict a new material, MnBi ultrathin film, with gigantic DM interactions. The ratio of the DM interaction to the Heisenberg exchange is about 0.3, exceeding any values reported so far. Its high Curie temperature, high coercivity, and large perpendicular magnetoanisotropy make MnBi a good candidate for future spintronics studies. Topologically nontrivial spin textures are emergent in this system. We expect further experimental efforts will be devoted into this systems.

  19. Unusual AIP mutation and phenocopy in the family of a young patient with acromegalic gigantism

    Directory of Open Access Journals (Sweden)

    Syed Ali Imran

    2018-01-01

    Full Text Available Early-onset acromegaly causing gigantism is often associated with aryl-hydrocarbon-interacting receptor protein (AIP mutation, especially if there is a positive family history. A15y male presented with tiredness and visual problems. He was 201 cm tall with a span of 217 cm. He had typical facial features of acromegaly, elevated IGF-1, secondary hypogonadism and a large macroadenoma. His paternal aunt had a history of acromegaly presenting at the age of 35 years. Following transsphenoidal surgery, his IGF-1 normalized and clinical symptoms improved. He was found to have a novel AIP mutation destroying the stop codon c.991T>C; p.*331R. Unexpectedly, his father and paternal aunt were negative for this mutation while his mother and older sister were unaffected carriers, suggesting that his aunt represents a phenocopy.

  20. Pituitary tumor with gigantism, acromegaly and preclinical Cushing's disease diagnosed from the 10th row.

    Science.gov (United States)

    Tourtelot, John B; Vesely, David L

    2013-08-01

    A 7'3" basketball player was noted to have 2 to 3 times thicker tissue in his hands than 6'10" players by an endocrinologist sitting 10 rows above the player in a basketball arena. This led to the diagnosis of pituitary gigantism where the history revealed that he was 7'3" at 15 years of age. At age 19 when the acryl enlargement was noted, a diagnostic workup revealed elevated growth hormones and insulin-like growth factor 1 (IGF-1) with a 2 × 1.3 cm pituitary tumor. His history suggested that his epiphyseal plates had closed at age 15, and because he continued to produce IGF-1, he now has acromegaly. His elevated adrenocorticotropic hormone (ACTH) before surgery suggests that he also had preclinical Cushing's disease. After pituitary transsphenoidal surgery, all acryl enlargement in hands and ligaments disappeared. His growth hormone, IGF-1 and ACTH returned to normal 2 weeks after surgery.

  1. Early descriptions of acromegaly and gigantism and their historical evolution as clinical entities.

    Science.gov (United States)

    Mammis, Antonios; Eloy, Jean Anderson; Liu, James K

    2010-10-01

    Giants have been a subject of fascination throughout history. Whereas descriptions of giants have existed in the lay literature for millennia, the first attempt at a medical description was published by Johannes Wier in 1567. However, it was Pierre Marie, in 1886, who established the term "acromegaly" for the first time and established a distinct clinical diagnosis with clear clinical descriptions in 2 patients with the characteristic presentation. Multiple autopsy findings revealed a consistent correlation between acromegaly and pituitary enlargement. In 1909, Harvey Cushing postulated a “hormone of growth" as the underlying pathophysiological trigger involved in pituitary hypersecretion in patients with acromegaly. This theory was supported by his observations of clinical remission in patients with acromegaly in whom he had performed hypophysectomy. In this paper, the authors present some of the early accounts of acromegaly and gigantism, and describe its historical evolution as a medical and surgical entity.

  2. Deep Invasive Fungal Infection of the Hand in a Child Mimicking a Local Gigantism.

    Science.gov (United States)

    Chatterjee, Anirban; Chatterjee, Shamita

    2018-04-01

    Subcutaneous and deep fungal infections in the hand are rare among children. These are usually found in immunocompromised adults or in persons engaged in soil handling activities, due to direct exposure, especially in the tropics. Delay in diagnosis is usual because pyogenic and other granulomatous infections are considered first. The authors present the case of a healthy, immunocompetent 2½-year-old child who presented with progressive swelling of the right hand mimicking a localized gigantism of the entire hand. Multiple operative drainage procedures done previously had failed to resolve the condition. A biopsy established the presence of fungal hyphae, thus confirming the diagnosis of deep fungal infection of the hand and guided proper therapeutic intervention. A strong index of suspicion needs to be maintained in cases not responding to conventional antibacterial therapy, and both microbiologic and histopathologic samples need to be obtained to establish the diagnosis.

  3. Gigantic optical magnetoelectric effect in CuB2O4

    International Nuclear Information System (INIS)

    Saito, Mitsuru; Taniguchi, Kouji; Arima, Taka-hisa

    2008-01-01

    Although it has been well known that materials in which both space inversion and time reversal symmetries are broken can host optical magneto-electric effect, i.e., change in optical constants with the reversal of propagating direction of light, the largest change in absorption ever reported on this effect was 0.2%. Here we show that optical absorption in noncentrosymmetric weak ferromagnetic material CuB 2 O 4 changes by more than 100% with reversal of a low magnetic field of 300 Oe. The gigantic optical magneto-electric effect is ascribed to the canted antiferromagnetic spin ordering of square-coordinated Cu 2+ sites, where the local inversion is slightly broken. (author)

  4. Gigantic spin splitting of exciton states in CdSe:Mn hexagonal crystal

    International Nuclear Information System (INIS)

    Komarov, A.V.; Ryabchenko, S.M.; Semenov, Yu.G.; Shanina, B.D.; Vitrikhovskij, N.I.; AN Ukrainskoj SSR, Kiev. Inst. Poluprovodnikov)

    1980-01-01

    Gigantic spin splitting of exciton states in magneto-doped semiconductors is observed for the first time in the CdSe: Mn hexagonal crystal. A theoretical interpretation of some features of the effect due to the anisotropy of the crystal is presented. The parameters of the band structure are determined by comparing with the experiments: Δ 1 =46+-3, Δ 2 =137+-1, Δ 3 =140.6+-0.3 meV. It is shown that in CdSe:Mn just as in cubic semiconductors, exchange interaction with magnetic impurities is ferromagnetic for electrons of the conductivity band and antiferromagnetic for electrons of the valence band. The exchange constants are of the same order of magnetude as those for the CdTe:Mn, ZnTe:Mn and ZnSe:Mn crystals

  5. Origin of gigantic magnetostriction and crystal field effects in terbium dititanate

    International Nuclear Information System (INIS)

    Aleksandrov, I.V.; Lidskij, B.V.; Mamsurova, L.G.

    1985-01-01

    The temperature and magnetic field dependences of the magnetostriction and magnetization and the temperature dependences of the magnetic susceptibility, specific heat and lattice parameter are investigated experimentally in a broad range of temperature and field strength for polycrystalline and single crystal Tb 2 Ti 2 O 7 . A conclusion is drawn regarding the structure of the energy levels of Tb 3+ in Tb 2 Ti 2 O 7 . A qualitative and quantitative explanation of all observed magnetic effects, and in particular of gigantic magnetostriction in Tb 2 Ti 2 O 7 , is presented which is based on the crystal field theory. It is shown that the huge magnitude of the magnetostriction in terbium dititanate is due to the specificity of the energy spectrum of Tb 3+ in Tb 2 Ti 2 O 7

  6. Giants among larges: how gigantism impacts giant virus entry into amoebae.

    Science.gov (United States)

    Rodrigues, Rodrigo Araújo Lima; Abrahão, Jônatas Santos; Drumond, Betânia Paiva; Kroon, Erna Geessien

    2016-06-01

    The proposed order Megavirales comprises the nucleocytoplasmic large DNA viruses (NCLDV), infecting a wide range of hosts. Over time, they co-evolved with different host cells, developing various strategies to penetrate them. Mimiviruses and other giant viruses enter cells through phagocytosis, while Marseillevirus and other large viruses explore endocytosis and macropinocytosis. These differing strategies might reflect the evolution of those viruses. Various scenarios have been proposed for the origin and evolution of these viruses, presenting one of the most enigmatic issues to surround these microorganisms. In this context, we believe that giant viruses evolved independently by massive gene/size gain, exploring the phagocytic pathway of entry into amoebas. In response to gigantism, hosts developed mechanisms to evade these parasites. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Contamination in sediments, bivalves and sponges of McMurdo Sound, Antarctica

    International Nuclear Information System (INIS)

    Negri, Andrew; Burns, Kathryn; Boyle, Steve; Brinkman, Diane; Webster, Nicole

    2006-01-01

    This study examined the concentrations of total hydrocarbons (THC), polychlorinated biphenyls (PCB), polyaromatic hydrocarbons (PAH), and trace metals (Cu, Zn, Cd, Pb, Hg and As) in marine sediments off Scott Base (NZ) and compared them with sediments near the highly polluted McMurdo Station (US) as well as less impacted sites including Turtle Rock and Cape Evans. The Antarctic mollusc, Laternula elliptica and three common sponge species were also analysed for trace metals. The mean THC concentration in sediments from Scott Base was 3 fold higher than the pristine site, Turtle Rock, but 10 fold lower than samples from McMurdo Station. McMurdo Station sediments also contained the highest concentrations of PAHs, PCBs and the trace metals, Cu, Zn, Pb, Cd and Hg. Copper was significantly higher in bivalves from McMurdo Station than other sites. Trace metal concentrations in sponges were generally consistent within sites but no spatial patterns were apparent. - Analyses of Antarctic marine sediments, bivalves and sponges revealed strong PAH, PCB and trace metal gradients in McMurdo Sound

  8. Boreholes on three bivalve species found on the sand beach at Sagot Cape, Baengnyeongdo, Korea

    Directory of Open Access Journals (Sweden)

    Dal-Yong Kong

    2017-12-01

    Full Text Available Circular to subcircular boreholes were found on the surfaces of three different bivalve shells (Mactra chinensis, Felaniella usta, and Nuttallia japonica that were pushed onto the sand beach at Sagot Cape, Baengnyeongdo, Korea. The boreholes are characterized by beveled holes that are parabolic in cross section. The boreholes are classified into the ichnospecies Oichnus paraboloides, probably drilled by a naticid gastropod Glossaulax didyma didyma living in the Baengnyeong tidal flat. In the case of Mactrashells, boreholes are observed more or less evenly on left and right valves, and 96% of boreholes are located on the umbo. This may suggest that the life position of the Baengnyeong bivalves did not dictate the preference of G. didyma didyma in the Baengnyeong tidal flat ecosystem. The clustered distribution of the boreholes in the umbo area indicates a strong site selectivity for boreholes that is quite a common phenomenon in many naticid gastropods. Keywords: Baengnyeongdo, Mactra chinensis, Naticid gastropods, Oichnus paraboloides, Prey–predator interactions

  9. Traces (ichnospecies Oichnus paraboloides of predatory gastropods on bivalve shells from the Seogwipo Formation, Jejudo, Korea

    Directory of Open Access Journals (Sweden)

    Dal-Yong Kong

    2015-12-01

    Full Text Available Circular to subcircular drill holes were identified on the bivalve shells collected from the Seogwipo Formation, Jejudo, Korea. A great majority of the drill holes (>70% were found on the surfaces of a bivalve species Glycymeris rotunda. They are characterized by a beveled sharp edge and paraboloid in cross section with larger outer borehole diameter (OBD; mean 4.21 mm and smaller inner borehole diameter (mean 2.94 mm. Walls of the drill holes are generally smooth, and walls ornamented with etched relief-like structures were also recognized. A slightly raised central boss observed in an incomplete specimen may indicate a failure of predator’s attack. All drill holes collected are classified as a single ichnospecies Oichnus paraboloides Bromley, 1981. They are interpreted as boring traces produced by predatory gastropods, particularly naticid gastropods. Most O. paraboloides boreholes are observed in the central area of shell surfaces; a few boreholes lie marginally, which may reflect a borehole-site selectivity. No correlation between size of prey (shell height and size of predator (OBD is recognized. It is likely, however, that drilled shells of about 30 mm in height represent optimal prey size for naticid predators that lived in a benthic Seogwipo community.

  10. Inducing the Alternative Oxidase Forms Part of the Molecular Strategy of Anoxic Survival in Freshwater Bivalves

    Directory of Open Access Journals (Sweden)

    Maria S. Yusseppone

    2018-02-01

    Full Text Available Hypoxia in freshwater ecosystems is spreading as a consequence of global change, including pollution and eutrophication. In the Patagonian Andes, a decline in precipitation causes reduced lake water volumes and stagnant conditions that limit oxygen transport and exacerbate hypoxia below the upper mixed layer. We analyzed the molecular and biochemical response of the North Patagonian bivalve Diplodon chilensis after 10 days of experimental anoxia (<0.2 mg O2/L, hypoxia (2 mg O2/L, and normoxia (9 mg O2/L. Specifically, we investigated the expression of an alternative oxidase (AOX pathway assumed to shortcut the regular mitochondrial electron transport system (ETS during metabolic rate depression (MRD in hypoxia-tolerant invertebrates. Whereas, the AOX system was strongly upregulated during anoxia in gills, ETS activities and energy mobilization decreased [less transcription of glycogen phosphorylase (GlyP and succinate dehydrogenase (SDH in gills and mantle]. Accumulation of succinate and induction of malate dehydrogenase (MDH activity could indicate activation of anaerobic mitochondrial pathways to support anoxic survival in D. chilensis. Oxidative stress [protein carbonylation, glutathione peroxidase (GPx expression] and apoptotic intensity (caspase 3/7 activity decreased, whereas an unfolded protein response (HSP90 was induced under anoxia. This is the first clear evidence of the concerted regulation of the AOX and ETS genes in a hypoxia-tolerant freshwater bivalve and yet another example that exposure to hypoxia and anoxia is not necessarily accompanied by oxidative stress in hypoxia-tolerant mollusks.

  11. Contamination in sediments, bivalves and sponges of McMurdo Sound, Antarctica

    Energy Technology Data Exchange (ETDEWEB)

    Negri, Andrew [Australian Institute of Marine Science, PMB 3, Townsville, Qld (Australia)]. E-mail: a.negri@aims.gov.au; Burns, Kathryn [Australian Institute of Marine Science, PMB 3, Townsville, Qld (Australia); Boyle, Steve [Australian Institute of Marine Science, PMB 3, Townsville, Qld (Australia); Brinkman, Diane [Australian Institute of Marine Science, PMB 3, Townsville, Qld (Australia); Webster, Nicole [Australian Institute of Marine Science, PMB 3, Townsville, Qld (Australia); Biological Sciences, University of Canterbury, Christchurch (New Zealand)

    2006-10-15

    This study examined the concentrations of total hydrocarbons (THC), polychlorinated biphenyls (PCB), polyaromatic hydrocarbons (PAH), and trace metals (Cu, Zn, Cd, Pb, Hg and As) in marine sediments off Scott Base (NZ) and compared them with sediments near the highly polluted McMurdo Station (US) as well as less impacted sites including Turtle Rock and Cape Evans. The Antarctic mollusc, Laternula elliptica and three common sponge species were also analysed for trace metals. The mean THC concentration in sediments from Scott Base was 3 fold higher than the pristine site, Turtle Rock, but 10 fold lower than samples from McMurdo Station. McMurdo Station sediments also contained the highest concentrations of PAHs, PCBs and the trace metals, Cu, Zn, Pb, Cd and Hg. Copper was significantly higher in bivalves from McMurdo Station than other sites. Trace metal concentrations in sponges were generally consistent within sites but no spatial patterns were apparent. - Analyses of Antarctic marine sediments, bivalves and sponges revealed strong PAH, PCB and trace metal gradients in McMurdo Sound.

  12. Inducing the Alternative Oxidase Forms Part of the Molecular Strategy of Anoxic Survival in Freshwater Bivalves

    Science.gov (United States)

    Yusseppone, Maria S.; Rocchetta, Iara; Sabatini, Sebastian E.; Luquet, Carlos M.; Ríos de Molina, Maria del Carmen; Held, Christoph; Abele, Doris

    2018-01-01

    Hypoxia in freshwater ecosystems is spreading as a consequence of global change, including pollution and eutrophication. In the Patagonian Andes, a decline in precipitation causes reduced lake water volumes and stagnant conditions that limit oxygen transport and exacerbate hypoxia below the upper mixed layer. We analyzed the molecular and biochemical response of the North Patagonian bivalve Diplodon chilensis after 10 days of experimental anoxia (<0.2 mg O2/L), hypoxia (2 mg O2/L), and normoxia (9 mg O2/L). Specifically, we investigated the expression of an alternative oxidase (AOX) pathway assumed to shortcut the regular mitochondrial electron transport system (ETS) during metabolic rate depression (MRD) in hypoxia-tolerant invertebrates. Whereas, the AOX system was strongly upregulated during anoxia in gills, ETS activities and energy mobilization decreased [less transcription of glycogen phosphorylase (GlyP) and succinate dehydrogenase (SDH) in gills and mantle]. Accumulation of succinate and induction of malate dehydrogenase (MDH) activity could indicate activation of anaerobic mitochondrial pathways to support anoxic survival in D. chilensis. Oxidative stress [protein carbonylation, glutathione peroxidase (GPx) expression] and apoptotic intensity (caspase 3/7 activity) decreased, whereas an unfolded protein response (HSP90) was induced under anoxia. This is the first clear evidence of the concerted regulation of the AOX and ETS genes in a hypoxia-tolerant freshwater bivalve and yet another example that exposure to hypoxia and anoxia is not necessarily accompanied by oxidative stress in hypoxia-tolerant mollusks. PMID:29527172

  13. Accumulation of butyl- and phenyltin compounds in starfish and bivalves from the coastal environment of Korea

    Energy Technology Data Exchange (ETDEWEB)

    Shim, Won Joon [Southern Coastal Environment Research Division, Korea Ocean Research and Development Institute, Jangmok-myon 391, Geoje 656-830 (Korea, Republic of)]. E-mail: wjshim@kordi.re.kr; Yim, Un Hyuk [Southern Coastal Environment Research Division, Korea Ocean Research and Development Institute, Jangmok-myon 391, Geoje 656-830 (Korea, Republic of); Kim, Nam Sook [Southern Coastal Environment Research Division, Korea Ocean Research and Development Institute, Jangmok-myon 391, Geoje 656-830 (Korea, Republic of); Hong, Sang Hee [Southern Coastal Environment Research Division, Korea Ocean Research and Development Institute, Jangmok-myon 391, Geoje 656-830 (Korea, Republic of); Oh, Jae Ryoung [Southern Coastal Environment Research Division, Korea Ocean Research and Development Institute, Jangmok-myon 391, Geoje 656-830 (Korea, Republic of); Jeon, Joong Kyun [Department of Marine Bioscience and Technology, Kangnung National University, Kangnung 210-702 (Korea, Republic of); Okamura, Hideo [Laboratory of Marine Environment Management, Kobe University Mercantile Marine, Fukaeminami 5-1-1, Highshinada, Kobe 658-0022 (Japan)

    2005-02-01

    Triphenyltin (TPT) and tributyltin (TBT) concentrations were determined in two starfish species (Asteria pectinifera and Asterias amurensis), bivalves (Crassostrea gigas or Mytilus edulis), and seawater samples from sites around the coasts of Korea. Both TPT and TBT concentrations in starfish ranged from 8 to 1560 ng/g and from <2 to 797 ng/g as Sn on a dry weight basis, respectively. TPT concentration accounted for 75.4% and 86.4% of total phenyltin concentration in A. pectinifera and A. amurensis, respectively, while monobutyltin, a degradation product of TBT, accounted for 86.3% and 57.2% of total butyltin, respectively. Triphenyltin concentrations in A. pectinifera were significantly correlated to water and bivalve TPT concentrations, which implies that dietary uptake of TPT from contaminated prey as well as direct uptake from surrounding water contribute to TPT body residues in the starfish. Starfish could be target organisms for monitoring TPT compound in the marine environment, due to their high accumulation and low degradation capacity towards TPT. - Starfish are effective organisms for monitoring phenyltin contamination in the marine environment.

  14. Accumulation of butyl- and phenyltin compounds in starfish and bivalves from the coastal environment of Korea

    International Nuclear Information System (INIS)

    Shim, Won Joon; Yim, Un Hyuk; Kim, Nam Sook; Hong, Sang Hee; Oh, Jae Ryoung; Jeon, Joong Kyun; Okamura, Hideo

    2005-01-01

    Triphenyltin (TPT) and tributyltin (TBT) concentrations were determined in two starfish species (Asteria pectinifera and Asterias amurensis), bivalves (Crassostrea gigas or Mytilus edulis), and seawater samples from sites around the coasts of Korea. Both TPT and TBT concentrations in starfish ranged from 8 to 1560 ng/g and from <2 to 797 ng/g as Sn on a dry weight basis, respectively. TPT concentration accounted for 75.4% and 86.4% of total phenyltin concentration in A. pectinifera and A. amurensis, respectively, while monobutyltin, a degradation product of TBT, accounted for 86.3% and 57.2% of total butyltin, respectively. Triphenyltin concentrations in A. pectinifera were significantly correlated to water and bivalve TPT concentrations, which implies that dietary uptake of TPT from contaminated prey as well as direct uptake from surrounding water contribute to TPT body residues in the starfish. Starfish could be target organisms for monitoring TPT compound in the marine environment, due to their high accumulation and low degradation capacity towards TPT. - Starfish are effective organisms for monitoring phenyltin contamination in the marine environment

  15. Mobile Element Evolution Playing Jigsaw - SINEs in Gastropod and Bivalve Mollusks.

    Science.gov (United States)

    Matetovici, Irina; Sajgo, Szilard; Ianc, Bianca; Ochis, Cornelia; Bulzu, Paul; Popescu, Octavian; Damert, Annette

    2016-01-06

    SINEs (Short INterspersed Elements) are widely distributed among eukaryotes. Some SINE families are organized in superfamilies characterized by a shared central domain. These central domains are conserved across species, classes, and even phyla. Here we report the identification of two novel such superfamilies in the genomes of gastropod and bivalve mollusks. The central conserved domain of the first superfamily is present in SINEs in Caenogastropoda and Vetigastropoda as well as in all four subclasses of Bivalvia. We designated the domain MESC (Romanian for MElc-snail and SCoica-mussel) because it appears to be restricted to snails and mussels. The second superfamily is restricted to Caenogastropoda. Its central conserved domain-Snail-is related to the Nin-DC domain. Furthermore, we provide evidence that a 40-bp subdomain of the SINE V-domain is conserved in SINEs in mollusks and arthropods. It is predicted to form a stable stem-loop structure that is preserved in the context of the overall SINE RNA secondary structure in invertebrates. Our analysis also recovered short retrotransposons with a Long INterspersed Element (LINE)-derived 5' end. These share the body and/or the tail with transfer RNA (tRNA)-derived SINEs within and across species. Finally, we identified CORE SINEs in gastropods and bivalves-extending the distribution range of this superfamily. © The Author(s) 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  16. Zoochorous dispersal of freshwater bivalves: an overlooked vector in biological invasions?

    Directory of Open Access Journals (Sweden)

    Coughlan Neil E.

    2017-01-01

    Full Text Available Vectors that underpin the natural dispersal of invasive alien species are frequently unknown. In particular, the passive dispersal (zoochory of one organism (or propagule by another, usually more mobile animal, remains poorly understood. Field observations of the adherence of invasive freshwater bivalves to other organisms have prompted us to assess the importance of zoochory in the spread of three prolific invaders: zebra mussel Dreissena polymorpha; quagga mussel Dreissena bugensis; and Asian clam Corbicula fluminea. An extensive, systematic search of the literature was conducted across multiple on-line scientific databases using various search terms and associated synonyms. In total, only five publications fully satisfied the search criteria. It appears that some fish species can internally transport viable adult D. polymorpha and C. fluminea specimens. Additionally, literature indicates that veligers and juvenile D. polymorpha can adhere to the external surfaces of waterbirds. Overall, literature suggests that zoochorous dispersal of invasive bivalves is possible, but likely a rare occurrence. However, even the establishment of a few individuals (or a single self-fertilising C. fluminea specimen can, over-time, result in a substantial population. Here, we highlight knowledge gaps, identify realistic opportunities for data collection, and suggest management protocols to mitigate the spread of invasive alien species.

  17. Assessing phototoxicity of petroleum using the bivalve Mulinia lateralis and the mysid Mysidopsis bahia

    International Nuclear Information System (INIS)

    Pelletier, M.; Champlin, D.; Burgess, R.; Ho, K.; Kuhn-Hines, A.

    1995-01-01

    One of the major inputs of PAHs in the marine environment is petroleum products. A large and often catastrophic source of petroleum is an oil spill, which releases concentrated quantities of PAHs into the water column. Intermediate molecular weight compounds remain in the water column for a relatively extended length of time. These compounds include phototoxic PAHs such as anthracene, fluoranthene, pyrene, and their substituted derivatives. Assessments of the environmental impact of marine oil spills have not included phototoxicity tests using pelagic larvae of benthic invertebrates. In this study, the photoreactive toxicity of individual PAHs, including anthracene, pyrene, and fluoranthene, were determined using the bivalve, Mulinia lateralis and the mysid, Mysidopsis bahia. Ultraviolet light exposures increased toxicity relative to fluorescent light for both species but a particularly dramatic response was seen using M. lateralis embryos. This species was relatively insensitive when exposed under fluorescent lights, but exhibited up to a 4,000 fold increase in toxicity under ultraviolet lights. Exposures with different types of petroleum (e.g., fuel oil number-sign 2 and crude oil) under fluorescent and ultraviolet light will demonstrate the utility of this bivalve and mysid for assessing oil spill-related acute and sublethal toxicity in the marine environment

  18. Immunotoxicity of nanoparticle nTiO2 to a commercial marine bivalve species, Tegillarca granosa.

    Science.gov (United States)

    Shi, Wei; Han, Yu; Guo, Cheng; Zhao, Xinguo; Liu, Saixi; Su, Wenhao; Zha, Shanjie; Wang, Yichen; Liu, Guangxu

    2017-07-01

    The increasing production and extensive application of nanoparticles (NPs) inevitably leads to increased release of NPs into the marine environment and therefore poses a potential threat to marine organisms, especially the sessile benthic bivalves. However, the impacts of NPs on the immunity of commercial and ecological important bivalve species, Tegillarca granosa, still remain unknown to date. In addition, the molecular mechanism of the immunotoxicity of NPs still remains unclear in marine invertebrates. Therefore, the immunotoxicity of nTiO 2 exposure to T. granosa at environmental realistic concentrations was investigated in the present study. Results obtained showed that the total number, phagocytic activity, and red granulocytes ratio of the haemocytes were significantly reduced after 30 days nTiO 2 exposures at the concentrations of 10 and 100 μg/L. Furthermore, the expressions of genes encoding Pattern Recognition Receptors (PPRs) and downstream immune-related molecules were significantly down-regulated by nTiO 2 exposures, indicating a reduced sensitivity to pathogen challenges. In conclusion, evident immunotoxicity of nTiO 2 to T. granosa at environmental realistic concentrations was detected by the present study. In addition, the gene expression analysis suggests that the PRRs (both TLRs and RIG1 investigated) may be the molecules for NPs recognition in marine invertebrates. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Can Oxygen Set Thermal Limits in an Insect and Drive Gigantism?

    Science.gov (United States)

    Verberk, Wilco C. E. P.; Bilton, David T.

    2011-01-01

    Background Thermal limits may arise through a mismatch between oxygen supply and demand in a range of animal taxa. Whilst this oxygen limitation hypothesis is supported by data from a range of marine fish and invertebrates, its generality remains contentious. In particular, it is unclear whether oxygen limitation determines thermal extremes in tracheated arthropods, where oxygen limitation may be unlikely due to the efficiency and plasticity of tracheal systems in supplying oxygen directly to metabolically active tissues. Although terrestrial taxa with open tracheal systems may not be prone to oxygen limitation, species may be affected during other life-history stages, particularly if these rely on diffusion into closed tracheal systems. Furthermore, a central role for oxygen limitation in insects is envisaged within a parallel line of research focussing on insect gigantism in the late Palaeozoic. Methodology/Principal Findings Here we examine thermal maxima in the aquatic life stages of an insect at normoxia, hypoxia (14 kPa) and hyperoxia (36 kPa). We demonstrate that upper thermal limits do indeed respond to external oxygen supply in the aquatic life stages of the stonefly Dinocras cephalotes, suggesting that the critical thermal limits of such aquatic larvae are set by oxygen limitation. This could result from impeded oxygen delivery, or limited oxygen regulatory capacity, both of which have implications for our understanding of the limits to insect body size and how these are influenced by atmospheric oxygen levels. Conclusions/Significance These findings extend the generality of the hypothesis of oxygen limitation of thermal tolerance, suggest that oxygen constraints on body size may be stronger in aquatic environments, and that oxygen toxicity may have actively selected for gigantism in the aquatic stages of Carboniferous arthropods. PMID:21818347

  20. Pegvisomant therapy in pituitary gigantism: successful treatment in a 12-year-old girl.

    Science.gov (United States)

    Rix, M; Laurberg, P; Hoejberg, A S; Brock-Jacobsen, B

    2005-08-01

    The use of a growth hormone (GH) receptor antagonist, pegvisomant has shown great promise in adults with acromegaly, but experience in paediatric patients is lacking. We aimed to describe the results of pegvisomant therapy in a 12-year-old girl with an aggressive GH-secreting pituitary tumour. To evaluate the ability of pegvisomant therapy to control the effects of peripheral GH excess in a case of pituitary gigantism. Pegvisomant was introduced at 10 mg/day, given subcutaneously, and gradually increased to 20 mg/day until serum IGF-I was normal for age. A large pituitary adenoma with suprasellar extension was diagnosed in a 12-year-old girl with progressive tall stature (178 cm), GH hypersecretion without suppression during oral glucose loading (nadir serum GH, 90 mU/l), high serum IGF-I and serum prolactin levels. Surgical extirpation was not possible because tumour tissue was fibrous and adherent to the optical nerves. Histological examination showed a mixed GH- and prolactin-secreting adenoma with lymphocytic infiltration of B and T cells. Treatment with a dopamine agonist, cabergoline, normalized serum prolactin, but GH secretion was resistant to both somatostatin analogue, octreotide and cabergoline. Radiation followed by pegvisomant therapy titrated up in dose to 20 mg/day led to a marked reduction in GH secretion and normalization of IGF-I, and to growth arrest and improvement of well-being. We suggest that treatment in pituitary gigantism with pegvisomant is safe and may normalize IGF-I levels and effectively stop growing.

  1. Can oxygen set thermal limits in an insect and drive gigantism?

    Directory of Open Access Journals (Sweden)

    Wilco C E P Verberk

    Full Text Available BACKGROUND: Thermal limits may arise through a mismatch between oxygen supply and demand in a range of animal taxa. Whilst this oxygen limitation hypothesis is supported by data from a range of marine fish and invertebrates, its generality remains contentious. In particular, it is unclear whether oxygen limitation determines thermal extremes in tracheated arthropods, where oxygen limitation may be unlikely due to the efficiency and plasticity of tracheal systems in supplying oxygen directly to metabolically active tissues. Although terrestrial taxa with open tracheal systems may not be prone to oxygen limitation, species may be affected during other life-history stages, particularly if these rely on diffusion into closed tracheal systems. Furthermore, a central role for oxygen limitation in insects is envisaged within a parallel line of research focussing on insect gigantism in the late Palaeozoic. METHODOLOGY/PRINCIPAL FINDINGS: Here we examine thermal maxima in the aquatic life stages of an insect at normoxia, hypoxia (14 kPa and hyperoxia (36 kPa. We demonstrate that upper thermal limits do indeed respond to external oxygen supply in the aquatic life stages of the stonefly Dinocras cephalotes, suggesting that the critical thermal limits of such aquatic larvae are set by oxygen limitation. This could result from impeded oxygen delivery, or limited oxygen regulatory capacity, both of which have implications for our understanding of the limits to insect body size and how these are influenced by atmospheric oxygen levels. CONCLUSIONS/SIGNIFICANCE: These findings extend the generality of the hypothesis of oxygen limitation of thermal tolerance, suggest that oxygen constraints on body size may be stronger in aquatic environments, and that oxygen toxicity may have actively selected for gigantism in the aquatic stages of Carboniferous arthropods.

  2. Assessment of Heavy Metals in Bivalves Molluscs of Apulian Region: a 3-years control activity of a EU Laboratory

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    Miedico O.

    2013-04-01

    Full Text Available The bivalve molluscs represent an important matrix to be studied for several reasons. Their nutritional properties make them valuable to the consumers, so that their consumption and commercial value has risen worldwide. Simultaneously, their significant water-filtering capability and their persistence in the same place make them good bio-indicators of marine ecosystems. The presence of the heavy metal contaminants, as Cd, Pb and Hg, was investigated in bivalve molluscs such as mussels (Mytilus galloprovincialis, clams (Venus gallina and oysters (Ostrea edulis. In the present study, a survey was carried out on 334 samples addressed to the Istituto Zooprofilattico Sperimentale – Puglia e Basilicata, Foggia (ITALY between 2009-2011, and collected by official authorities along the coasts of Apulia Region. The conformity of heavy metal content in bivalve molluscs was verified, in according to EC Reg. 1881/2006. The compliance was found for the total amount of samples. The obtained data on heavy metals concentration in bivalve molluscs were compared with data found in monitoring studies on the incidence of heavy metals in 1981 in North-Western Mediterranean Sea, in 2003 in Tyrrhenian Sea and in 2010 in Pacific Ocean (Chile, reported in literature. The information obtained from this work offer an essential database, not only for the authorities involved in food control, but also for the official institutions responsible of a constant control of the marine ecosystem pollution.

  3. Uniform Variation in Genetic-Traits of a Marine Bivalve Related to Starvation, Pollution and Geographic Clines

    NARCIS (Netherlands)

    Hummel, H.; Bogaards, R.H.; Amiard-Triquet, C.; Bachelet, G.; Desprez, M.; Marchand, J.; Rybarczyk, H.; Sylvand, B.; De Wit, Y.; De Wolf, L.

    1995-01-01

    Consistent patterns of genetic variation in the marine bivalve Macoma balthica (L.) were found after exposure to low levels of copper, starvation, and along geographic dines. The geographic dines were related to temperature and salinity. Genetic differences were primarily found in the LAP (Leucine

  4. The potential accumulation of polycyclic aromatic hydrocarbons in phytoplankton and bivalves in Can Gio coastal wetland, Vietnam.

    Science.gov (United States)

    Thuy, Hoang Thi Thanh; Loan, Tu Thi Cam; Phuong, Trinh Hong

    2018-05-12

    Polycyclic aromatic hydrocarbons (PAHs) are one of the most important classes of anthropogenic persistent organic contaminants in the marine environment. This review discusses a whole range of findings that address various aspects of the bioaccumulation of PAHs in two common marine biota (phytoplankton and bivalves) globally and especially for Can Gio coastal wetland, Vietnam. The published information and collected data on the bioconcentration and accumulation mechanisms of PAHs as well as implications for Can Gio coastal wetland are compiled for phytoplankton and bivalves. PAHs are still released to Can Gio coastal environments from various sources and then transported to coastal environments through various physical processes; they may enter marine food chains and be highly accumulated in phytoplankton and bivalves. Thus, PAHs' bioaccumulation should be considered as one important criterion to assess the water's quality, directly linked to human health due to seafood consumption. Ecologically, Can Gio coastal wetland plays an important role to the South Vietnam key economic zone. However, it is also an area of potential PAHs inputs. With the abundant phytoplankton and bivalves in Can Gio coastal wetland, the PAHs bioaccumulation in these biota is inevitably detected. Thus, further study on the bioavailability of these contaminants is urgently needed in order to mitigate their negative effects and protect the ecosystems.

  5. Subcellular compartmentalization of Cd and Zn in two bivalves. II. Significance of trophically available metal (TAM)

    Science.gov (United States)

    Wallace, W.G.; Luoma, S.N.

    2003-01-01

    This paper examines how the subcellular partitioning of Cd and Zn in the bivalves Macoma balthica and Potamocorbula amurensis may affect the trophic transfer of metal to predators. Results show that the partitioning of metals to organelles, 'enzymes' and metallothioneins (MT) comprise a subcellular compartment containing trophically available metal (TAM; i.e. metal trophically available to predators), and that because this partitioning varies with species, animal size and metal, TAM is similarly influenced. Clams from San Francisco Bay, California, were exposed for 14 d to 3.5 ??g 1-1 Cd and 20.5 ??g 1-1 Zn, including 109Cd and 65Zn as radiotracers, and were used in feeding experiments with grass shrimp Palaemon macrodatylus, or used to investigate the subcellular partitioning of metal. Grass shrimp fed Cd-contaminated P. amurensis absorbed ???60% of ingested Cd, which was in accordance with the partitioning of Cd to the bivalve's TAM compartment (i.e. Cd associated with organelles, 'enzymes' and MT); a similar relationship was found in previous studies with grass shrimp fed Cd-contaminated oligochaetes. Thus, TAM may be used as a tool to predict the trophic transfer of at least Cd. Subcellular fractionation revealed that ???34% of both the Cd and Zn accumulated by M. balthica was associated with TAM, while partitioning to TAM in P. amurensis was metal-dependent (???60% for TAM-Cd%, ???73% for TAM-Zn%). The greater TAM-Cd% of P. amurensis than M. balthica is due to preferential binding of Cd to MT and 'enzymes', while enhanced TAM-Zn% of P. amurensis results from a greater binding of Zn to organelles. TAM for most species-metal combinations was size-dependent, decreasing with increased clam size. Based on field data, it is estimated that of the 2 bivalves, P. amurensis poses the greater threat of Cd exposure to predators because of higher tissue concentrations and greater partitioning as TAM; exposure of Zn to predators would be similar between these species.

  6. A Gray-purple Mass on the Floor of the Mouth: Gigantic Mucogingival Pyogenic Granuloma in a Teenage Patient.

    Science.gov (United States)

    Brunet-LLobet, Lluís; Miranda-Rius, Jaume; Lahor-Soler, Eduard; Mrina, Ombeni; Nadal, Alfons

    2014-01-01

    Pyogenic granuloma is defined as a benign neoplasm of vascular phenotype. This case describes the clinical and histopathological features of a gigantic mucogingival pyogenic granuloma, in a 14-year-old healthy black boy. This exophytic gray-purple mass, related to a toothpick injury, had more than twelve-month evolution on the anterior mandible involving lingual area besides to the floor of the mouth pressing the right salivary duct. Conservative excision was performed, followed by uncomplicated healing with no recurrence in two years. The histopathological examination reported a pyogenic granuloma (lobular capillary haemangioma). The authors provide a discussion of the presurgical differential diagnosis of the lesion. This case report presents an extremely uncommon location of a gigantic pyogenic granuloma, involving mucogingival complex and affecting the salivary outflow. This clinical manuscript may shed light on the controversies about possible mechanisms inducing oral pyogenic granuloma.

  7. Análisis socioeconómico de la pesquería de calamar gigante en Guaymas, Sonora

    Directory of Open Access Journals (Sweden)

    Francisco Javier de la Cruz-González

    2011-01-01

    Full Text Available En este trabajo hacemos un análisis socioeconómico de la pesquería de calamar gigante en Guaymas, Sonora. Se generó una base de datos con información pesquera y se aplicó una encuesta a pescadores y a trabajadores de la industria del calamar para determinar sus principales características socioeconómicas. Los resultados muestran que esta pesquería ha tenido una participación importante en la estructura productiva del sector pesquero de la región; sin embargo, el repunte en las capturas de calamar gigante en los últimos años ha permitido el crecimiento de esta pesquería, pero no su desarrollo. El documento resalta la necesidad de orientar las políticas de manejo al aprovechamiento integral de este recurso.

  8. Polyostotic fibrous dysplasia with gigantism and huge pelvic tumor: a rare case of McCune-Albright syndrome.

    Science.gov (United States)

    Sakayama, Kenshi; Sugawara, Yoshifumi; Kidani, Teruki; Fujibuchi, Taketsugu; Kito, Katsumi; Tanji, Nozomu; Nakamura, Atsushi

    2011-06-01

    We report a rare case of polyostotic fibrous dysplasia on endocrine hyperfunction with elevated human growth hormone and normal serum level of prolactin. There were some differential points of gender, gigantism, endocrine function, and GNAS gene from McCune-Albright syndrome. Malignant transformation was suspected in the pelvic tumor from imaging because rapid growth of the tumor by imaging was observed; however, no malignant change occurred in this case.

  9. Uptake and metabolism of 14C-chloropyrifos by marine bivalves

    International Nuclear Information System (INIS)

    Zhong, C.G.; Chen, S.; Zhao, X.; Shi, J.; Carvalho, F.P.

    1999-01-01

    The uptake and metabolism of 14 C-chlorpyrifos by two marine bivalves, Paphia undulata and Sinonovacula constricta, were studied in a simulated ecosystem. The experiments were carried out in two 30 L glass tanks containing each 20 L of filtered sea water, contaminated with 14 C-chlorpyrifos 1.85x10 4 Bq.L -1 (16.7 μg.L -1 ) at the beginning of the exposure period. At different time intervals, three specimens of each species were sampled for analysis of the pesticide in the molluscs tissues. The 14 C-chlorpyrifos residues were extracted from the digestive gland of the molluscs and analyzed by co-chromatography with pesticide standards by TLC methods described before

  10. An orphan G-protein-coupled receptor causes human gigantism and/or acromegaly: Molecular biology and clinical correlations.

    Science.gov (United States)

    Trivellin, Giampaolo; Hernández-Ramírez, Laura C; Swan, Jeremy; Stratakis, Constantine A

    2018-04-01

    X-linked acrogigantism (X-LAG) is a recently described form of familial or sporadic pituitary gigantism characterized by very early onset GH and IGF-1 excess, accelerated growth velocity, gigantism and/or acromegaloid features. Germline or somatic microduplications of the Xq26.3 chromosomal region, invariably involving the GPR101 gene, constitute the genetic defect leading to X-LAG. GPR101 encodes a class A G protein-coupled receptor that activates the 3',5'-cyclic adenosine monophosphate signaling pathway. Highly expressed in the central nervous system, the main physiological function and ligand of GPR101 remain unknown, but it seems to play a role in the normal development of the GHRH-GH axis. Early recognition of X-LAG cases is imperative because these patients require clinical management that differs from that of other patients with acromegaly or gigantism. Medical treatment with pegvisomant seems to be the best approach, since X-LAG tumors are resistant to the treatment with somatostatin analogues and dopamine agonists; surgical cure requires near-total hypophysectomy. Currently, the efforts of our research focus on the identification of GPR101 ligands; in addition, the long-term follow-up of X-LAG patients is of extreme interest as this is expected to lead to better understanding of GPR101 effects on human pathophysiology. Copyright © 2018. Published by Elsevier Ltd.

  11. Using transplanted bivalves to assess oil exposure and effects in Delaware Bay

    International Nuclear Information System (INIS)

    Salazar, M.; Salazar, S.; Mearns, A.; Venosa, A.; Eberhart, B.

    1995-01-01

    To evaluate the effectiveness of bioremediation, the US EPA oiled intertidal plots in Delaware Bay and monitored oil degradation rates. This controlled release of oil was also used to test the utility of transplanted bivalves in assessing oil spills and to evaluate the extent and potential effects of the release. Measuring the accumulation of oil in bivalve tissues was used to estimate exposure and the extent of contamination. Growth was used to estimate potential bioeffects. Approximately 1,800 mussels and 1,200 oysters were transplanted to 11 intertidal sites. Five treatment sites were within 1 meter of the lower end of the oiled plots. A total of six sites were used as controls, three on either side of the oiled plots at 5, 10, and 100 m. Samples were taken on Day 0, 2, 15, and 28 to estimate the rate of bioaccumulation. All of the mussels died within the first week of exposure; oysters exhibited over 95% survival but growth was minimal. The authors found a statistically significant difference in tissue weights when comparing treatment sites with control sites. The total concentration of polynuclear aromatic hydrocarbons (PAHs) in tissues of oysters nearest the oiled plots increased by a factor of four after an exposure period of two days. PAH concentrations in control oysters nearest the mouth of the bay increased slightly but the differences were not statistically significant. The control oysters nearest the head of the bay received an intermediate dose which was depurated by the end of the 28-day experiment. PAHs in the oysters nearest the oiled plots approached but did not return to background levels by the end of the test

  12. Assessing the presence of marine toxins in bivalve molluscs from southwest India.

    Science.gov (United States)

    Turner, Andrew D; Dhanji-Rapkova, Monika; Rowland-Pilgrim, Stephanie; Turner, Lucy M; Rai, Ashwin; Venugopal, Moleyur N; Karunasagar, Indrani; Godhe, Anna

    2017-12-15

    The south west coast of India has been showing a steady increase in shellfish cultivation both for local consumption and fishery export, over recent years. Perna viridis and Crassostrea madrasensis are two species of bivalve molluscs which grow in some selected regions of southern Karnataka, close to the city of Mangalore. In the early 1980s, shellfish consumers in the region were affected by intoxication from Paralytic Shellfish Poison present in local bivalves (clams and oysters) resulting in hospitalisation of many, including one fatality. Since then, there have been no further reports of serious shellfish intoxication and there is little awareness of the risks from natural toxins and no routine monitoring programme in place to protect shellfish consumers. This study presents the findings from the first ever systematic assessment of the presence of marine toxins in mussels and oysters grown in four different shellfish harvesting areas in the region. Shellfish were collected and subjected to analysis for ASP, PSP and lipophilic toxins, as well as a suite of non-EU regulated toxins such as tetrodotoxin and selected cyclic imines. Results revealed the presence of low levels of PSP toxins in oysters throughout the study period. Overall, total toxicities reached a maximum of 10% of the EU regulatory limit of 800 μg STX eq/kg. Toxin profiles were similar to those reported from the 1980 outbreak. No evidence was found for significant levels of ASP and lipophilic toxins, although some cyclic imines were detected, including gymnodimine. The results indicated that the risk to shellfish consumers during this specific study period would have been low. However, with historical evidence for extremely high levels of PSP toxins in molluscs, there is a strong need for routine surveillance of shellfish production areas for marine toxins, in order to mitigate against human health impacts resulting from unexpected harmful algal blooms, with potentially devastating socio

  13. Hepatitis A and E Viruses in Wastewaters, in River Waters, and in Bivalve Molluscs in Italy.

    Science.gov (United States)

    Iaconelli, M; Purpari, G; Della Libera, S; Petricca, S; Guercio, A; Ciccaglione, A R; Bruni, R; Taffon, S; Equestre, M; Fratini, M; Muscillo, M; La Rosa, Giuseppina

    2015-12-01

    Several studies have reported the detection of hepatitis A (HAV) and E (HEV) virus in sewage waters, indicating a possibility of contamination of aquatic environments. The objective of the present study was to assess the occurrence of HAV and HEV in different water environments, following the route of contamination from raw sewage through treated effluent to the surface waters receiving wastewater discharges . Bivalve molluscan shellfish samples were also analyzed, as sentinel of marine pollution. Samples were tested by RT-PCR nested type in the VP1/2A junction for HAV, and in the ORF1 and ORF2 regions for HEV. Hepatitis A RNA was detected in 12 water samples: 7/21 (33.3%) raw sewage samples, 3/21 (14.3%) treated sewage samples, and 2/27 (7.4%) river water samples. Five sequences were classified as genotype IA, while the remaining 7 sequences belonged to genotype IB. In bivalves, HAV was detected in 13/56 samples (23.2%), 12 genotype IB and one genotype IA. Whether the presence of HAV in the matrices tested indicates the potential for waterborne and foodborne transmission is unknown, since infectivity of the virus was not demonstrated. HEV was detected in one raw sewage sample and in one river sample, both belonging to genotype 3. Sequences were similar to sequences detected previously in Italy in patients with autochthonous HEV (no travel history) and in animals (swine). To our knowledge, this is the first detection of HEV in river waters in Italy, suggesting that surface water can be a potential source for exposure .

  14. Impact of seawater carbonate chemistry on the calcification of marine bivalves

    Science.gov (United States)

    Thomsen, J.; Haynert, K.; Wegner, K. M.; Melzner, F.

    2015-07-01

    Bivalve calcification, particularly of the early larval stages, is highly sensitive to the change in ocean carbonate chemistry resulting from atmospheric CO2 uptake. Earlier studies suggested that declining seawater [CO32-] and thereby lowered carbonate saturation affect shell production. However, disturbances of physiological processes such as acid-base regulation by adverse seawater pCO2 and pH can affect calcification in a secondary fashion. In order to determine the exact carbonate system component by which growth and calcification are affected it is necessary to utilize more complex carbonate chemistry manipulations. As single factors, pCO2 had no effects and [HCO3-] and pH had only limited effects on shell growth, while lowered [CO32-] strongly impacted calcification. Dissolved inorganic carbon (CT) limiting conditions led to strong reductions in calcification, despite high [CO32-], indicating that [HCO3-] rather than [CO32-] is the inorganic carbon source utilized for calcification by mytilid mussels. However, as the ratio [HCO3-] / [H+] is linearly correlated with [CO32-] it is not possible to differentiate between these under natural seawater conditions. An equivalent of about 80 μmol kg-1 [CO32-] is required to saturate inorganic carbon supply for calcification in bivalves. Below this threshold biomineralization rates rapidly decline. A comparison of literature data available for larvae and juvenile mussels and oysters originating from habitats differing substantially with respect to prevailing carbonate chemistry conditions revealed similar response curves. This suggests that the mechanisms which determine sensitivity of calcification in this group are highly conserved. The higher sensitivity of larval calcification seems to primarily result from the much higher relative calcification rates in early life stages. In order to reveal and understand the mechanisms that limit or facilitate adaptation to future ocean acidification, it is necessary to better

  15. Futures, fakes and discourses of the gigantic and miniature in ‘The World’ islands, Dubai

    Directory of Open Access Journals (Sweden)

    Pamila Gupta

    2015-11-01

    Full Text Available This article takes the “island” as a key trope in tourism studies, exploring how ideas of culture and nature, as well as those of paradise (lost are central to its interpretation for tourists and tourist industries alike. Increasingly, however, island tourism is blurring the line between geographies of land and water, continent and archipelago, and private and public property. The case of ‘The World’ islands mega project off the coast of Dubai (UAE is used to chart the changing face and future of island tourism, exploring how spectacle, branding and discourses of the gigantic, miniature, and fake, particularly alongside technological mediations on a large-scale, reflect the postmodern neoliberal world of tourism and the liquid times in which we live. Artificial island complexes such as this one function as cosmopolitan ‘non-places’ at the same time that they reflect a resurgence in (British nascent nationalism and colonial nostalgia, all the whilst operating in a sea of ‘junkspace’. The shifting cartography of ‘the island’ is thus mapped out to suggest new forms of place-making and tourism’s evolving relationship to these floating islandscapes.

  16. Evolución de planetas gigantes y posibilidades de su detección directa

    Science.gov (United States)

    Brunini, A.; Benvenuto, O. G.

    Desde la reciente detección de planetas gigantes orbitando estrellas cercanas de tipo solar por medio de efecto Doppler, uno de los principales problemas, en cuanto al estudio de los sistemas planetarios extrasolares, se refiere a la posibilidad de obtener evidencia directa de su existencia. Esto parece ser factible gracias a que en un futuro cercano entrarán en operación algunos telescopios especialmente adecuados a estos propósitos. Por tal motivo, hemos comenzado desde hace un tiempo un esfuerzo en cuanto al estudio de la evolución planetaria. A tales efectos hemos adaptado el código de evolución estelar de nuestro Observatorio al caso planetario. Las principales diferencias entre el caso estelar y el planetario se encuentran en la ecuación de estado. A tales fines hemos incluído la reciente ecuación de estado de Saumon, Chabrier y Van Horn, las opacidades radiativas de Guillot et al., procesos de quema de Deuterio, etc. También se ha considerado la posible existencia de fases de hielo y roca en el interior planetario. Por el momento hemos despreciado los efectos de la rotación planetaria. Con este código hemos computado la evolución de planetas con masas desde 10 hasta 0.3 masas de Júpiter. Utilizando nuestros resultados numéricos discutimos la detectabilidad de estos objetos en condiciones realistas.

  17. Discovery of gigantic molecular nanostructures using a flow reaction array as a search engine.

    Science.gov (United States)

    Zang, Hong-Ying; de la Oliva, Andreu Ruiz; Miras, Haralampos N; Long, De-Liang; McBurney, Roy T; Cronin, Leroy

    2014-04-28

    The discovery of gigantic molecular nanostructures like coordination and polyoxometalate clusters is extremely time-consuming since a vast combinatorial space needs to be searched, and even a systematic and exhaustive exploration of the available synthetic parameters relies on a great deal of serendipity. Here we present a synthetic methodology that combines a flow reaction array and algorithmic control to give a chemical 'real-space' search engine leading to the discovery and isolation of a range of new molecular nanoclusters based on [Mo(2)O(2)S(2)](2+)-based building blocks with either fourfold (C4) or fivefold (C5) symmetry templates and linkers. This engine leads us to isolate six new nanoscale cluster compounds: 1, {Mo(10)(C5)}; 2, {Mo(14)(C4)4(C5)2}; 3, {Mo(60)(C4)10}; 4, {Mo(48)(C4)6}; 5, {Mo(34)(C4)4}; 6, {Mo(18)(C4)9}; in only 200 automated experiments from a parameter space spanning ~5 million possible combinations.

  18. A Thermodynamic, kinematic and microphysical analysis of a jet and gigantic jet-producing Florida thunderstorm

    Science.gov (United States)

    Lazarus, S. M.; Splitt, M. E.; Brownlee, James; Spiva, Nicholas; Liu, Ningyu

    2015-08-01

    This paper presents a meteorological analysis of a storm that produced two jets, four gigantic jets (GJ), and a starter, which were observed by two radars as well as the Kennedy Space Center 4-Dimensional Lightning Surveillance System on 3 August 2013 in Central Florida. The work is the first application of dual polarization data to a jet-producing storm and is the fifth case related to a tropical disturbance. The storm environment is consistent with the moist tropical paradigm that characterizes about three quarters of the surface and aircraft observed jet and GJ events. The most unstable (MU) convective available potential energy is not unusual for Florida summer convection and is below the climatological mean for these events. An unusual speed shear layer is located near the storm equilibrium level (EL) and the storm exhibits a tilted structure with CGs displaced upshear. The turbulence, as measured by the eddy dissipation rate, is extreme near the storm top during the event window, consistent with the GJ mixing hypothesis. The individual events are collocated with, and track along, the center axis of the divergent outflow at the EL and occur within the region of the coldest GOES IR temperatures—placing the events within the overshoot. The dual polarization data indicate a deep graupel column, extending above the mixed phase layer, to a 13 km altitude.

  19. Multiple organ gigantism caused by mutation in VmPPD gene in blackgram (Vigna mungo).

    Science.gov (United States)

    Naito, Ken; Takahashi, Yu; Chaitieng, Bubpa; Hirano, Kumi; Kaga, Akito; Takagi, Kyoko; Ogiso-Tanaka, Eri; Thavarasook, Charaspon; Ishimoto, Masao; Tomooka, Norihiko

    2017-03-01

    Seed size is one of the most important traits in leguminous crops. We obtained a recessive mutant of blackgram that had greatly enlarged leaves, stems and seeds. The mutant produced 100% bigger leaves, 50% more biomass and 70% larger seeds though it produced 40% less number of seeds. We designated the mutant as multiple-organ-gigantism ( mog ) and found the mog phenotype was due to increase in cell numbers but not in cell size. We also found the mog mutant showed a rippled leaf ( rl ) phenotype, which was probably caused by a pleiotropic effect of the mutation. We performed a map-based cloning and successfully identified an 8 bp deletion in the coding sequence of VmPPD gene, an orthologue of Arabidopsis PEAPOD ( PPD ) that regulates arrest of cell divisions in meristematic cells . We found no other mutations in the neighboring genes between the mutant and the wild type. We also knocked down GmPPD genes and reproduced both the mog and rl phenotypes in soybean. Controlling PPD genes to produce the mog phenotype is highly valuable for breeding since larger seed size could directly increase the commercial values of grain legumes.

  20. Technical treatment options for the mill effluents of the Los Gigantes Complex

    International Nuclear Information System (INIS)

    Asenjo, A.R.

    2002-01-01

    The Mining/Milling Los Gigantes Complex is located in Cordoba Province, about 100 km to the West of the capital city. The uranium mining and milling activities have been carried out during the period between 1980 and 1990. As result of those activities, mine wastes, low grade ore, sludge, heap leach wastes and liquid effluents have been accumulated in the site. At present, the National Atomic Energy Commission of Argentina is developing the Remediation Project of the site. Within the frame of this Project it is necessary to define the liquid effluent treatment methodology of the liquids accumulated in a pond in order to achieve the proper quality to be released to the environment, according with the national and provincial regulations. In this paper several liquid treatment methods are described. These methods were also developed at the lab scale. Among these we can mention hot and cool alcalinization with barium chloride addition and ion exchange resins treatments. Also a pilot scale assay has been done in the site (about 450 m 3 ) in order to verify the obtained lab scale results. Nevertheless that other assays are yet under developing, the obtained results are reported. (author)

  1. Endochondral gigantism: a newly recognized skeletal dysplasia with pre- and postnatal overgrowth and endocrine abnormalities.

    Science.gov (United States)

    Schmidt, Heinrich; Kammer, Birgit; Grasser, Monika; Enders, Angelika; Rost, Imma; Kiess, Wieland

    2007-08-15

    We report on a 3-year-old male, born at 34 weeks of gestation, with marked pre- and postnatal overgrowth, birth weight of 6,600 g, length of 61 cm, and head circumference of 38.5 cm. A striking phenotype was recorded at birth, which became more evident during the follow-up period. He had macrobrachycephaly, facial abnormalities, small thoracic cage, long trunk, deformed spine, rhizomelia, large hands and feets, absent subcutaneous fat, small umbilical hernia, inguinal hernias, and large joints with mild contractures. Hypoglycemic episodes and obstructive apnea complicated the neonatal period. During follow-up, overgrowth continued with a height of 146 cm (+11.65 SDS) and a weight of 39 kg (BMI 18.3 kg/m(2)) at 3.5 years. Endocrinological work-up disclosed extremely low levels of growth hormone, insulin-like growth factors, and insulin. What makes our patient unique is the association of marked prenatal overgrowth; unusual phenotype; skeletal dysplasia caused by accelerated endochondral ossification resulting in cartilage hyperplasia of the skull base and spine, and postnatal gigantism; and complete absence of subcutaneous fat. Other well-known overgrowth syndromes were excluded. We hypothesize that autocrine/paracrine growth factors could be the cause of excessive endochondral ossification. Alternately, activating mutations in transcription factors involved in both growth and endocrine/metabolic homeostasis could be responsible for this unusual phenotype. (c) 2007 Wiley-Liss, Inc.

  2. A Gigantic Jet Observed Over an Mesoscale Convective System in Midlatitude Region

    Science.gov (United States)

    Yang, Jing; Sato, Mitsuteru; Liu, Ningyu; Lu, Gaopeng; Wang, Yu; Wang, Zhichao

    2018-01-01

    Gigantic jets (GJs) are mostly observed over summer tropical or tropical-like thunderstorms. This study reports observation of a GJ over a mesoscale convective system (MCS) in the midlatitude region in eastern China. The GJ is observed over a relatively weak radar reflectivity region ahead of the leading line, and the maximum radar echo top along the GJ azimuth was lower than the tropopause in the same region, significantly different from past studies that indicate summer GJs are usually associated with convective surges or overshooting tops. Also different from most of previous observations showing GJ-producing summer thunderstorms only produced GJ type of transient luminous events during their life cycles, two sprites were also captured in a time window of 15 min containing the GJ, indicating that the MCS provides favorable conditions not only for the GJ but also for the sprites. The balloon-borne soundings of the MCS show that there were large wind shears in the middle and upper levels of the thundercloud, which may have played important roles for the GJ production.

  3. Comparative Analysis of Vertebrate Dystrophin Loci Indicate Intron Gigantism as a Common Feature

    Science.gov (United States)

    Pozzoli, Uberto; Elgar, Greg; Cagliani, Rachele; Riva, Laura; Comi, Giacomo P.; Bresolin, Nereo; Bardoni, Alessandra; Sironi, Manuela

    2003-01-01

    The human DMD gene is the largest known to date, spanning > 2000 kb on the X chromosome. The gene size is mainly accounted for by huge intronic regions. We sequenced 190 kb of Fugu rubripes (pufferfish) genomic DNA corresponding to the complete dystrophin gene (FrDMD) and provide the first report of gene structure and sequence comparison among dystrophin genomic sequences from different vertebrate organisms. Almost all intron positions and phases are conserved between FrDMD and its mammalian counterparts, and the predicted protein product of the Fugu gene displays 55% identity and 71% similarity to human dystrophin. In analogy to the human gene, FrDMD presents several-fold longer than average intronic regions. Analysis of intron sequences of the human and murine genes revealed that they are extremely conserved in size and that a similar fraction of total intron length is represented by repetitive elements; moreover, our data indicate that intron expansion through repeat accumulation in the two orthologs is the result of independent insertional events. The hypothesis that intron length might be functionally relevant to the DMD gene regulation is proposed and substantiated by the finding that dystrophin intron gigantism is common to the three vertebrate genes. [Supplemental material is available online at www.genome.org.] PMID:12727896

  4. Lower limb gigantism, lymphedema, and painful varicosities following a thigh vascular access graft.

    Science.gov (United States)

    Thompson, Michael; Mathuram Thiyagarajan, Umasankar; Akoh, Jacob A

    2014-07-01

    Prosthetic arteriovenous grafts (AVGs) are associated with greater morbidity than autogenous arteriovenous fistulas (AVFs), but their use is indicated when AVF formation is not possible. This report adds to the literature a case of lower limb gigantism, painful varicosities, and lymphedema following long-term use of AVG in the upper thigh. The patient's past medical history included renal transplantation on the same side well before the AVG was inserted and right leg deep vein thrombosis. Suspicion of AVG thrombosis was excluded by Doppler ultrasound, which demonstrated an access flow of 1700 mL/min. A computed tomography (CT) scan of the abdomen and pelvis did not identify the cause of her symptoms. Whereas functional incompetence of the iliac vein valve might be responsible for the varicosities, the extent of hypertrophy in this case raises the suspicion of lymphatic blockage possibly secondary to groin dissection undertaken at the time of graft insertion, in addition to the previous dissection at the time of transplantation. This case highlights the need for minimal groin dissection during AVG insertion, particularly in patients with a history of previous abdominopelvic surgery. © 2014 International Society for Hemodialysis.

  5. A Paleocene penguin from New Zealand substantiates multiple origins of gigantism in fossil Sphenisciformes.

    Science.gov (United States)

    Mayr, Gerald; Scofield, R Paul; De Pietri, Vanesa L; Tennyson, Alan J D

    2017-12-12

    One of the notable features of penguin evolution is the occurrence of very large species in the early Cenozoic, whose body size greatly exceeded that of the largest extant penguins. Here we describe a new giant species from the late Paleocene of New Zealand that documents the very early evolution of large body size in penguins. Kumimanu biceae, n. gen. et sp. is larger than all other fossil penguins that have substantial skeletal portions preserved. Several plesiomorphic features place the new species outside a clade including all post-Paleocene giant penguins. It is phylogenetically separated from giant Eocene and Oligocene penguin species by various smaller taxa, which indicates multiple origins of giant size in penguin evolution. That a penguin rivaling the largest previously known species existed in the Paleocene suggests that gigantism in penguins arose shortly after these birds became flightless divers. Our study therefore strengthens previous suggestions that the absence of very large penguins today is likely due to the Oligo-Miocene radiation of marine mammals.

  6. Change in the immunophenotype of a somatotroph adenoma resulting in gigantism.

    Science.gov (United States)

    Thawani, Jayesh P; Bailey, Robert L; Burns, Carrie M; Lee, John Y K

    2014-01-01

    Examining the pathologic progression of a pituitary adenoma from the point of a prepubescent child to an adult with gigantism affords us an opportunity to consider why patients may develop secretory or functioning tumors and raises questions about whether therapeutic interventions and surveillance strategies could be made to avoid irreversible phenotypic changes. A patient underwent a sublabial transsphenoidal resection for a clinically non-functioning macroadenoma in 1999. He underwent radiation treatment and was transiently given growth hormone (GH) supplementation as an adolescent. His growth rapidly traversed several percentiles and he was found to have elevated GH levels. The patient became symptomatic and was taken for a second neurosurgical procedure. Pathology and immunohistochemical staining demonstrated a significantly higher proportion of somatotroph cells and dense granularity; he was diagnosed with a functional somatotroph adenoma. While it is likely that the described observations reflect the manifestations of a functional somatotroph adenoma in development, it is possible that pubertal growth, GH supplementation, its removal, or radiation therapy contributed to the described endocrine and pathologic changes.

  7. Respiratory evolution facilitated the origin of pterosaur flight and aerial gigantism.

    Directory of Open Access Journals (Sweden)

    Leon P A M Claessens

    Full Text Available Pterosaurs, enigmatic extinct Mesozoic reptiles, were the first vertebrates to achieve true flapping flight. Various lines of evidence provide strong support for highly efficient wing design, control, and flight capabilities. However, little is known of the pulmonary system that powered flight in pterosaurs. We investigated the structure and function of the pterosaurian breathing apparatus through a broad scale comparative study of respiratory structure and function in living and extinct archosaurs, using computer-assisted tomographic (CT scanning of pterosaur and bird skeletal remains, cineradiographic (X-ray film studies of the skeletal breathing pump in extant birds and alligators, and study of skeletal structure in historic fossil specimens. In this report we present various lines of skeletal evidence that indicate that pterosaurs had a highly effective flow-through respiratory system, capable of sustaining powered flight, predating the appearance of an analogous breathing system in birds by approximately seventy million years. Convergent evolution of gigantism in several Cretaceous pterosaur lineages was made possible through body density reduction by expansion of the pulmonary air sac system throughout the trunk and the distal limb girdle skeleton, highlighting the importance of respiratory adaptations in pterosaur evolution, and the dramatic effect of the release of physical constraints on morphological diversification and evolutionary radiation.

  8. Earth’s oldest ‘Bobbit worm’ – gigantism in a Devonian eunicidan polychaete

    Science.gov (United States)

    Eriksson, Mats E.; Parry, Luke A.; Rudkin, David M.

    2017-01-01

    Whilst the fossil record of polychaete worms extends to the early Cambrian, much data on this group derive from microfossils known as scolecodonts. These are sclerotized jaw elements, which generally range from 0.1–2 mm in size, and which, in contrast to the soft-body anatomy, have good preservation potential and a continuous fossil record. Here we describe a new eunicidan polychaete, Websteroprion armstrongi gen. et sp. nov., based primarily on monospecific bedding plane assemblages from the Lower-Middle Devonian Kwataboahegan Formation of Ontario, Canada. The specimens are preserved mainly as three-dimensional moulds in the calcareous host rock, with only parts of the original sclerotized jaw walls occasionally present. This new taxon has a unique morphology and is characterized by an unexpected combination of features seen in several different Palaeozoic polychaete families. Websteroprion armstrongi was a raptorial feeder and possessed the largest jaws recorded in polychaetes from the fossil record, with maxillae reaching over one centimetre in length. Total body length of the species is estimated to have reached over one metre, which is comparable to that of extant ‘giant eunicid’ species colloquially referred to as ‘Bobbit worms’. This demonstrates that polychaete gigantism was already a phenomenon in the Palaeozoic, some 400 million years ago. PMID:28220886

  9. Unusual AIP mutation and phenocopy in the family of a young patient with acromegalic gigantism.

    Science.gov (United States)

    Imran, Syed Ali; Aldahmani, Khaled A; Penney, Lynette; Croul, Sidney E; Clarke, David B; Collier, David M; Iacovazzo, Donato; Korbonits, Márta

    2018-01-01

    Early-onset acromegaly causing gigantism is often associated with aryl-hydrocarbon-interacting receptor protein ( AIP ) mutation, especially if there is a positive family history. A15y male presented with tiredness and visual problems. He was 201 cm tall with a span of 217 cm. He had typical facial features of acromegaly, elevated IGF-1, secondary hypogonadism and a large macroadenoma. His paternal aunt had a history of acromegaly presenting at the age of 35 years. Following transsphenoidal surgery, his IGF-1 normalized and clinical symptoms improved. He was found to have a novel AIP mutation destroying the stop codon c.991T>C; p.*331R. Unexpectedly, his father and paternal aunt were negative for this mutation while his mother and older sister were unaffected carriers, suggesting that his aunt represents a phenocopy. Typical presentation for a patient with AIP mutation with excess growth and eunuchoid proportions.Unusual, previously not described AIP variant with loss of the stop codon.Phenocopy may occur in families with a disease-causing germline mutation.

  10. Surgical trauma induces overgrowth in lower limb gigantism: regulation with use of rapamycin is promising.

    Science.gov (United States)

    Pinto, Rohan Sebastian; Harrison, William David; Graham, Kenneth; Nayagam, Durai

    2018-01-04

    We describe an unclassified overgrowth syndrome characterised by unregulated growth of dermal fibroblasts in the lower limbs of a 35-year-old woman. A PIK3CA gene mutation resulted in lower limb gigantism. Below the waist, she weighed 117 kg with each leg measuring over 100 cm in circumference. Her total adiposity was 50% accounted for by her legs mainly. Liposuction and surgical debulking were performed to reduce the size of the limbs but had exacerbated the overgrowth in her lower limbs. Systemic sepsis from an infected foot ulcer necessitated treatment by an above-knee amputation. Postoperatively, the stump increased in size by 19 kg. A trial of rapamycin to reverse the growth of the stump has shown promise. We discuss the clinical and genetic features of this previously unclassified disorder and the orthopaedic considerations involved. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  11. Multi-instrumental observations of a positive gigantic jet produced by a winter thunderstorm in Europe

    Science.gov (United States)

    van der Velde, Oscar A.; Bór, József; Li, Jingbo; Cummer, Steven A.; Arnone, Enrico; Zanotti, Ferruccio; Füllekrug, Martin; Haldoupis, Christos; Naitamor, Samir; Farges, Thomas

    2010-12-01

    At 2336:56 UTC on 12 December 2009, a bright gigantic jet (GJ) was recorded by an observer in Italy. Forty-nine additional sprites, elves, halos and two cases of upward lightning were observed that night. The location of the GJ corresponded to a distinct cloud top (-34°C) west of Ajaccio, Corsica. The GJ reached approximately 91 km altitude, with a "trailing jet" reaching 49-59 km, matching with earlier reported GJs. The duration was short at 120-160 ms. This is the first documented GJ which emerged from a maritime winter thunderstorm only 6.5 km tall, showing high cloud tops are not required for initiation of GJs. In the presence of strong vertical wind shear, the meteorological situation was different from typical outbreaks of fall and winter thunderstorms in the Mediterranean. During the trailing jet phase of the GJ, a sprite with halo triggered by a nearby cloud-to-ground lightning flash occurred at a relatively low altitude (origins in the cloud (i.e., a positive cloud-to-ionosphere discharge, +CI), with a large total charge moment change of 11600 C km and a maximum current of 3.3 kA. Early VLF transmitter amplitude perturbations detected concurrently with the GJ confirm the production of large conductivity changes due to electron density enhancements in the D-region of the ionosphere.

  12. Respiratory evolution facilitated the origin of pterosaur flight and aerial gigantism.

    Science.gov (United States)

    Claessens, Leon P A M; O'Connor, Patrick M; Unwin, David M

    2009-01-01

    Pterosaurs, enigmatic extinct Mesozoic reptiles, were the first vertebrates to achieve true flapping flight. Various lines of evidence provide strong support for highly efficient wing design, control, and flight capabilities. However, little is known of the pulmonary system that powered flight in pterosaurs. We investigated the structure and function of the pterosaurian breathing apparatus through a broad scale comparative study of respiratory structure and function in living and extinct archosaurs, using computer-assisted tomographic (CT) scanning of pterosaur and bird skeletal remains, cineradiographic (X-ray film) studies of the skeletal breathing pump in extant birds and alligators, and study of skeletal structure in historic fossil specimens. In this report we present various lines of skeletal evidence that indicate that pterosaurs had a highly effective flow-through respiratory system, capable of sustaining powered flight, predating the appearance of an analogous breathing system in birds by approximately seventy million years. Convergent evolution of gigantism in several Cretaceous pterosaur lineages was made possible through body density reduction by expansion of the pulmonary air sac system throughout the trunk and the distal limb girdle skeleton, highlighting the importance of respiratory adaptations in pterosaur evolution, and the dramatic effect of the release of physical constraints on morphological diversification and evolutionary radiation.

  13. A gigantic new dinosaur from Argentina and the evolution of the sauropod hind foot.

    Science.gov (United States)

    González Riga, Bernardo J; Lamanna, Matthew C; Ortiz David, Leonardo D; Calvo, Jorge O; Coria, Juan P

    2016-01-18

    Titanosauria is an exceptionally diverse, globally-distributed clade of sauropod dinosaurs that includes the largest known land animals. Knowledge of titanosaurian pedal structure is critical to understanding the stance and locomotion of these enormous herbivores and, by extension, gigantic terrestrial vertebrates as a whole. However, completely preserved pedes are extremely rare among Titanosauria, especially as regards the truly giant members of the group. Here we describe Notocolossus gonzalezparejasi gen. et sp. nov. from the Upper Cretaceous of Mendoza Province, Argentina. With a powerfully-constructed humerus 1.76 m in length, Notocolossus is one of the largest known dinosaurs. Furthermore, the complete pes of the new taxon exhibits a strikingly compact, homogeneous metatarsus--seemingly adapted for bearing extraordinary weight--and truncated unguals, morphologies that are otherwise unknown in Sauropoda. The pes underwent a near-progressive reduction in the number of phalanges along the line to derived titanosaurs, eventually resulting in the reduced hind foot of these sauropods.

  14. Abnormalities in bivalve larvae from the Puck Bay (Gulf of Gdansk, southern Baltic Sea) as an indicator of environmental pollution.

    Science.gov (United States)

    Lasota, Rafal; Gierszewska, Katarzyna; Viard, Frédérique; Wolowicz, Maciej; Dobrzyn, Katarzyna; Comtet, Thierry

    2018-01-01

    This study described the occurrence of abnormalities in bivalve larvae from the Puck Bay. Analyses of plankton samples collected in 2012-2013 showed that larval Mytilus trossulus, Mya arenaria, and Cerastoderma glaucum exhibited abnormalities that could indicate adverse environmental impacts. The deformities were mainly in shells, but missing soft tissue fragments and protruding vela were also noted. In addition to larval studies, we analyzed benthic postlarvae of Mytilus trossulus. Interestingly, grooves and notches at different locations of the prodissoconch, dissoconch, and shell margin were observed. Some of these deformations were reminiscent of the indentations found on the shell edge of larvae. Comparing the proportion of abnormal postlarvae to larvae with shell abnormalities suggested that the survival of larvae with shell abnormalities was low. Overall, our results suggested that the ratio of abnormal bivalve larvae could be used as an indicator of the biological effects of hazardous substances in the pelagic environment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Molecular and Biochemical Methods Useful for the Epigenetic Characterization of Chromatin-Associated Proteins in Bivalve Molluscs

    Directory of Open Access Journals (Sweden)

    Ciro Rivera-Casas

    2017-08-01

    Full Text Available Bivalve molluscs constitute a ubiquitous taxonomic group playing key functions in virtually all ecosystems, and encompassing critical commercial relevance. Along with a sessile and filter-feeding lifestyle in most cases, these characteristics make bivalves model sentinel organisms routinely used for environmental monitoring studies in aquatic habitats. The study of epigenetic mechanisms linking environmental exposure and specific physiological responses (i.e., environmental epigenetics stands out as a very innovative monitoring strategy, given the role of epigenetic modifications in acclimatization and adaptation. Furthermore, the heritable nature of many of those modifications constitutes a very promising avenue to explore the applicability of epigenetic conditioning and selection in management and restoration strategies. Chromatin provides a framework for the study of environmental epigenetic responses. Unfortunately, chromatin and epigenetic information are very limited in most non-traditional model organisms and even completely lacking in most environmentally and ecologically relevant organisms. The present work aims to provide a comprehensive and reproducible experimental workflow for the study of bivalve chromatin. First, a series of guidelines for the molecular isolation of genes encoding chromatin-associated proteins is provided, including information on primers suitable for conventional PCR, Rapid Amplification of cDNA Ends (RACE, genome walking and quantitative PCR (qPCR experiments. This section is followed by the description of methods specifically developed for the analysis of histone and SNBP proteins in different bivalve tissues, including protein extraction, purification, separation and immunodetection. Lastly, information about available antibodies, their specificity and performance is also provided. The tools and protocols described here complement current epigenetic analyses (usually limited to DNA methylation by incorporating

  16. Biochemical and behavioural responses of the endobenthic bivalve Scrobicularia plana to silver nanoparticles in seawater and microalgal food.

    Science.gov (United States)

    Buffet, Pierre-Emmanuel; Pan, Jin-Fen; Poirier, Laurence; Amiard-Triquet, Claude; Amiard, Jean-Claude; Gaudin, Pierre; Risso-de Faverney, Christine; Guibbolini, Marielle; Gilliland, Douglas; Valsami-Jones, Eugenia; Mouneyrac, Catherine

    2013-03-01

    Because of their bactericidal effects, Ag nanoparticles (Ag NPs) have promising industrial development but could lead to potential ecological risks. The aim of this study was to examine the uptake and effect of silver (soluble or as lactate Ag NPs of 40 nm) at low concentrations (10 μg L(-1)) in the endobenthic bivalve Scrobicularia plana exposed, for 14 days, directly (water) or via the diet (microalgae). The stability of Ag NPs in seawater was examined using dynamic light scattering. Release of soluble Ag from Ag NPs in the experimental media was quantified by using diffusive gradient in thin film. Bioaccumulation of Ag in bivalves was measured by electrothermal atomic absorption spectrometry. Behavioural and biochemical biomarkers were determined in bivalves. Aggregation of Ag NPs and the release of soluble Ag from Ag NPs were observed in the experimental media. For both forms of Ag, bioaccumulation was much more important for waterborne than for dietary exposure. The response of oxidative stress biomarkers (catalase, glutathion S-transferase, superoxide dismutase) was more important after dietary than waterborne exposure to Ag (soluble and NPs). These defences were relatively efficient since they led to a lack of response of damage biomarkers. Burrowing was not affected for bivalves exposed directly or through the diet to both Ag forms but feeding behaviour was impaired after 10 days of dietary exposure. Since no differences of responses to Ag either soluble or nanoparticulate were observed, it seems that labile Ag released from Ag NPs was mainly responsible for toxicity. Copyright © 2012 Elsevier Inc. All rights reserved.

  17. Polychlorinated biphenyls, organochlorine pesticides and polycyclic aromatic hydrocarbons in a one-off global survey of bivalves

    DEFF Research Database (Denmark)

    Vorkamp, Katrin; Strand, Jakob; Christensen, Jan H.

    2010-01-01

    During the Danish Galathea 3 expedition, bivalve samples were collected at the Faroe Islands, Greenland, Ghana, South Africa, Australia, Solomon Islands, New Zealand, Chile, US Virgin Islands, Boston, Newfoundland and Shetland Islands and analysed for organochlorines and PAHs. Concentration...... in terms of PCB and PAH levels, while other Greenland samples came closest to representing PAH background levels. Several locations had undetectable organochlorine levels, including Hobart and Chile, which had the lowest Sigma PAH concentrations (group the stations...

  18. Investigation into Cryptosporidium and Giardia in bivalve mollusks farmed in Sardinia region and destined for human consumption

    Directory of Open Access Journals (Sweden)

    Tiziana Tedde

    2013-06-01

    Full Text Available Cryptosporidium and Giardia are protozoan parasites transmitted by fecal-oral ingestion of (oocysts, and are responsible for enteritis in several animal species and humans worldwide. These (oocysts can survive for over a year in aquatic environments and can accumulate in bivalve mollusks, which filter large volumes of water. The aim of this study is to evaluate the natural occurrence of Cryptosporidium and Giardia contamination in different specimens of edible bivalves mollusks from farming sites of the western and north-eastern coasts of Sardinia. From April 2011 to February 2012, 1095 specimens of Mytilus galloprovincialis and 240 of Crassostrea gigas were sampled from Olbia and Oristano gulf and San Teodoro pond. Hepatopancreas and gills, including the labial palp, were examined for oocysts and cysts after pooling and homogenisation using different techniques: i staining for light and fluorescence microscopy; ii direct immunofluorescence (IF Merifluor® test Cryptosporidium/ Giardia (Meridian Bioscience Inc., Cincinnati, OH, USA; and iii molecular procedures. However, in the context under study, all mollusks examined with the three main diagnostic techniques were negative for both parasites pointing out the hypothetically low zoonotic risk related to Cryptosporidium and Giardia in bivalves, especially Mytilus galloprovincialis and Crassostrea gigas.

  19. Element availability of bivalve with symbiotic zooxanthellae in coral sea area as studied by multielement profiling analysis

    Science.gov (United States)

    Itoh, A.; Kabe, N.

    2008-12-01

    In coral sea, a characteristic ecosystem is formed by many kinds of marine animals and plants, although seawater is uneutrophic. This may be explained by the fact that various chemical species with bioessentiality are effectively taken and used by lower animals and plants in coral sea area. A symbiotic relationship often found among different animals and plants in this area is considered to be working as one of such processes. However, the specific bioavailability of the elements for the marine animals and plants in coral reef area has not been studied from the viewpoints of trace and ultratrace elements. It is found by the present authors that bivalve with symbiotic zooxanthellae (Tridacna crocea) living on coral reef had relatively higher bio- accumulation factors for many bio-essential elements than other kinds of bivalves, although they live in the uneutrophic sea area. The present authors focused on Tridacna crocea as one of the symbiotic animals. Thus, in the present study, at first, multielement determination of major-to-ultratrace elements (about 20 elements) in each organ of Tridacna crocea with symbiotic zooxanthellae, were carried out by ICP-AES, ICP- MS, and CHN coder. At Second, the specific bioavailability of trace and ultratrace elements in Tridacna crocea was discussed on the multielement data for seawater, seaweeds, and other bivalves in coral sea area.

  20. Manganese in the shell of the bivalve Mytilus edulis: Seawater Mn or physiological control?

    Science.gov (United States)

    Freitas, Pedro S.; Clarke, Leon J.; Kennedy, Hilary; Richardson, Christopher A.

    2016-12-01

    Manganese in the shell calcite of marine bivalves has been suggested to reflect ambient seawater Mn concentrations, thus providing a high-resolution archive of past seawater Mn concentrations. However, a quantitative relationship between seawater Mn and shell Mn/Ca ratios, as well as clear understanding of which process(es) control(s) shell Mn/Ca, are still lacking. Blue mussels, Mytilus edulis, were grown in a one-year duration field experiment in the Menai Strait, U.K., to study the relationship between seawater particulate and dissolved Mn2+ concentrations and shell calcite Mn/Ca ratios. Shell Mn/Ca showed a well-defined intra-annual double-peak, with maximum values during early spring and early summer and low values during autumn and winter. Seawater particulate Mn peaked during winter and autumn, with a series of smaller peaks during spring and summer, whereas dissolved Mn2+ exhibited a marked single maximum during late-spring to early-summer, being low during the remainder of the year. Consequently, neither seawater particulate Mn nor dissolved Mn2+ concentrations explain the intra-annual variation of shell Mn/Ca ratios. A physiological control on shell Mn/Ca ratios is evident from the strong similarity and timing of the double-peaked intra-annual variations of Mn/Ca and shell growth rate (SGR), the latter corresponding to periods of increased metabolic activity (as indicated by respiration rate). It is thus likely that in M. edulis SGR influences shell Mn/Ca by altering the concentration or activity of Mn2+ within the extra-pallial fluid (EPF), by changing the flux of Mn into or the proportion of protein bound Mn within the EPF. By linking shell Mn/Ca ratios to the endogenous and environmental factors that determine growth and metabolic activity, this study helps to explain the lack of a consistent relationship between shell Mn/Ca in marine bivalve shell calcite and seawater particulate and dissolved Mn2+ concentrations. The use of Mn content from M. edulis

  1. Calibration of hydroclimate proxies in freshwater bivalve shells from Central and West Africa

    Science.gov (United States)

    Kelemen, Zita; Gillikin, David P.; Graniero, Lauren E.; Havel, Holly; Darchambeau, François; Borges, Alberto V.; Yambélé, Athanase; Bassirou, Alhou; Bouillon, Steven

    2017-07-01

    Freshwater bivalve shell oxygen and carbon stable isotope ratios (δ18O, δ13C) may act as recorders of hydroclimate (e.g., precipitation-evaporation balance, discharge) and aquatic biogeochemistry. We investigate the potential of these hydroclimate proxies measured along the growth axis of shells collected from the Oubangui River (Bangui, Central African Republic) and the Niger River (Niamey, Niger). Biweekly water samples and in situ measurements collected over several years, along with daily discharge data from both sites allowed a direct comparison with proxies recorded in the shells. Data from a total of 14 unionid shells, including three species (Chambardia wissmanni, Aspatharia dahomeyensis, and Aspatharia chaiziana), confirmed that shells precipitate carbonate in oxygen isotope equilibrium with ambient water. Because water temperature variations were small, shell δ18O values (δ18Oshell) also accurately record the seasonality and the range observed in water δ18O (δ18Ow) values when calculated using an average temperature. Calculated δ18Ow values were in good agreement over the entire record of measured δ18Ow values, thus δ18Oshell records can be reliably used to reconstruct past δ18Ow values. Discharge and δ18Ow values from both rivers fit a logarithmic relationship, which was used to attempt reconstruction of past hydrological conditions, after calculating δ18Ow values from δ18Oshell values. A comparison with measured discharge data suggests that for the two rivers considered, δ18Oshell data are good proxies for recording discharge conditions during low(er) discharge levels, but that high discharge values cannot be accurately reconstructed due to the large scatter in the discharge-δ18Ow relationship. Moreover, periods of bivalve shell growth cessation due to high turbidity or air exposure should be taken into account. While δ13C values of dissolved inorganic carbon in both rivers showed clear seasonality and correlated well with discharge

  2. Anatomical study on Myoforceps aristatus, an invasive boring bivalve in S.E. Brazilian coast (Mytilidae

    Directory of Open Access Journals (Sweden)

    Luiz Ricardo L. Simone

    2006-01-01

    Full Text Available The bivalve Myoforceps aristatus (Dillwyn, 1817, also known as Lithophaga aristata, have been recently collected in the coasts of Rio de Janeiro and São Paulo, Brazil; a species that bores shells of other mollusks. This occurrence has been interpreted as an invasion of this species, originally from the Caribbean. The distinguishing character of the species is the posterior extensions of the shell crossing with each other. Because specimens with this character have also been collected in the Pacific Ocean, they all have been considered a single species. However, it is possible that more than one species may be involved in such worldwide distribution. With the objective of providing full information based on Atlantic specimens, a complete anatomical description is provided, which can be used in comparative studies with specimens from other oceans. Additional distinctive features of M. aristatus are the complexity of the incurrent siphon, the kidney opening widely into the supra-branchial chamber (instead of via a nephropore, and the multi-lobed auricle.O bivalve Myoforceps aristatus (Dillwyn, 1817, também conhecido como Lithophaga aristata, tem sido recentemente coletado nas costas do Rio de Janeiro e São Paulo, Brasil; uma espécie que perfura conchas de outros moluscos. Esta ocorrência está sendo interpretada como uma invasão de uma espécie originada do Caribe. O caráter distintivo da espécie é a região posterior da concha, com extensões que se cruzam. Como espécimes com esta característica também têm sido coletados no oceano Pacífico, eles tem sido considerados como pertencentes à mesma espécie. Entretanto, é possível que mais de uma espécie possam estar envolvidas nesta suposta distribuição mundial. Com o objetivo de fornecer informação completa baseada em material do Atlântico, uma descrição anatômica completa é dada, a qual pode ser usada em estudos comparativos com espécimes de outros oceanos. As caracter

  3. Parasites of economically important bivalves from the southern coast of Bahia State, Brazil Parasitos de bivalves de interesse econômico no Litoral Sul do Estado da Bahia, Brasil

    Directory of Open Access Journals (Sweden)

    Gabriela Calvi Zeidan

    2012-12-01

    Full Text Available This study investigated the parasites of three commercially important bivalve species (Crassostrea rhizophorae, Mytella guyanensis and Lucina pectinata from the southern coast of Bahia, Brazil. A total of 540 specimens were collected in August 2009 and February 2010, at three localities. The bivalve specimens were measured on their longest axis, opened, and macroscopically examined for the presence of parasites or signs of disease. They were then fixed in Davidson' solution and subjected to routine histological processing, with paraffin embedding and H&E staining; next, the specimens were examined under a light microscope. No parasites were observed associated with L. pectinata. Rickettsia-like organisms (RLOs, Sphenophrya sp. (Ciliophora, Nematopsis sp. (Apicomplexa, Urastoma sp. (Turbellaria and Bucephalus sp. (Digenea were observed in both C. rhizophorae and M. guyanensis, as well as Ancistrocoma sp. (Ciliophora and Tylocephalum sp. (Cestoda in the former. A high prevalence of Nematopsis sp. was seen, but caused no apparent damage to the host. Bucephalus sp. caused the destruction of tissues, with castration, but showed low prevalence. The other parasites occurred in low prevalence and intensity, without causing significant damage.Neste estudo foram investigados os parasitos de três espécies de bivalves de interesse econômico (Crassostrea rhizophorae, Mytella guyanensis e Lucina pectinata da Bahia. Foram analisados 540 exemplares, obtidos em duas coletas (agosto-2009 e fevereiro-2010, em três localidades. Os bivalves foram medidos quanto ao seu maior eixo, abertos e examinados macroscopicamente quanto à presença de parasitos ou sinais de enfermidades. Depois disso, foram fixados em solução de Davidson e processados por rotina de histologia, com inclusão em parafina e coloração com H&E. O material foi examinado ao microscópio de luz. Nenhum parasito esteve associado a L. pectinata. Bactérias do tipo RLOs (organismos assemelhados a

  4. Acromegaly and gigantism in the medical literature. Case descriptions in the era before and the early years after the initial publication of Pierre Marie (1886).

    Science.gov (United States)

    de Herder, Wouter W

    2009-01-01

    In 1886 Pierre Marie used the term "acromegaly" for the first time and gave a full description of the characteristic clinical picture. However several others had already given clear clinical descriptions before him and sometimes had given the disease other names. After 1886, it gradually became clear that pituitary enlargement (caused by a pituitary adenoma) was the cause and not the consequence of acromegaly, as initially thought. Pituitary adenomas could be found in the great majority of cases. It also became clear that acromegaly and gigantism were the same disease but occurring at different stages of life and not different diseases as initially thought. At the end of the 19th and beginning of the 20th century most information was derived from case descriptions and post-mortem examinations of patients with acromegaly or (famous) patients with gigantism. The stage was set for further research into the pathogenesis, diagnosis and therapy of acromegaly and gigantism.

  5. Efficacy and safety of long-acting pasireotide in Japanese patients with acromegaly or pituitary gigantism: results from a multicenter, open-label, randomized, phase 2 study.

    Science.gov (United States)

    Tahara, Shigeyuki; Murakami, Mami; Kaneko, Tomomi; Shimatsu, Akira

    2017-07-28

    A multicenter, open-label, phase 2 study was conducted to investigate the efficacy and safety of long-acting pasireotide formulation in Japanese patients with acromegaly or pituitary gigantism. Medically naïve or inadequately controlled patients (on somatostatin analogues or dopamine agonists) were included. Primary end point was the proportion of all patients who achieved biochemical control (mean growth hormone [GH] levelsacromegaly, n=32; pituitary gigantism, n=1) were enrolled and randomized 1:1:1 to receive open-label pasireotide 20mg, 40mg, or 60mg. The median age was 52 years (range, 31-79) and 20 patients were males. At month 3, 18.2% of patients (6/33; 90% confidence interval: 8.2%, 32.8%) had biochemical control (21.2% [7/33] when including a patient with mean GHacromegaly or pituitary gigantism.

  6. Gigantic Circular Shock Acoustic Waves in the Ionosphere Triggered by the Launch of FORMOSAT-5 Satellite

    Science.gov (United States)

    Chou, Min-Yang; Shen, Ming-Hsueh; Lin, Charles C. H.; Yue, Jia; Chen, Chia-Hung; Liu, Jann-Yenq; Lin, Jia-Ting

    2018-02-01

    The launch of SpaceX Falcon 9 rocket delivered Taiwan's FORMOSAT-5 satellite to orbit from Vandenberg Air Force Base in California at 18:51:00 UT on 24 August 2017. To facilitate the delivery of FORMOSAT-5 to its mission orbit altitude of 720 km, the Falcon 9 made a steep initial ascent. During the launch, the supersonic rocket induced gigantic circular shock acoustic waves (SAWs) in total electron content (TEC) over the western United States beginning approximately 5 min after the liftoff. The circular SAWs emanated outward with 20 min duration, horizontal phase velocities of 629-726 m/s, horizontal wavelengths of 390-450 km, and period of 10.28 ± 1 min. This is the largest rocket-induced circular SAWs on record, extending approximately 114-128°W in longitude and 26-39°N in latitude ( 1,500 km in diameter), and was due to the unique, nearly vertical attitude of the rocket during orbit insertion. The rocket-exhaust plume subsequently created a large-scale ionospheric plasma hole ( 900 km in diameter) with 10-70% TEC depletions in comparison with the reference days. While the circular SAWs, with a relatively small amplitude of TEC fluctuations, likely did not introduce range errors into the Global Navigation Satellite Systems navigation and positioning system, the subsequent ionospheric plasma hole, on the other hand, could have caused spatial gradients in the ionospheric plasma potentially leading to a range error of 1 m.

  7. Parâmetros astrofísicos de estrelas gigantes do aglomerado globular 47 Tucanae

    Science.gov (United States)

    Alves-Brito, A.; Barbuy, B.

    2003-08-01

    Os aglomerados globulares são considerados laboratórios astrofísicos para a verificação da teoria de evolução estelar, bem como a trajetória químio-dinâmica das galáxias hospedeiras. Em particular, 47 Tucanae (NGC 104) configura-se como um dos mais extensivamente estudados aglomerados globulares da Galáxia devido a relativa proximidade ao Sol (R¤ = 4.5 kpc) e alta latitute galáctica (b = -44°,89). Neste trabalho, apresentamos a velocidade radial heliocêntrica e os parâmetros atmosféricos (Teff, logg, [Fe/H]) de 5 estrelas gigantes do aglomerado globular 47 Tucanae. Os espectros foram obtidos pelo espectrógrafo UVES (Ultaviolet Visual Echelle Spectrograph) de alta resolução (R = 60000) e alta razão sinal-ruído (S/N > 200), acoplado ao telescópio de 8,2m Kueyen do VLT (Very Large Telescope). Nós encontramos = -22,43 +/- 3,97 km/s, [Fe/H] ~ -0.7, 1,2 estrelas cobrem um intervalo de magnitude 12,2 < V < 14,2. Os parâmetros atmosféricos são fundamentais para a construção de espectros sintéticos de outros aglomerados globulares ricos em metais. Trabalho financiado pela FAPESP e pelo CNPq.

  8. Giant retroperitoneal lipoma: a case report Lipoma gigante do retroperitônio: relato de caso

    Directory of Open Access Journals (Sweden)

    Carlos Augusto Real Martinez

    2003-12-01

    Full Text Available BACKGROUND: Retroperitoneal lipoma is an extremely rare neoplasm. AIMS: The authors report a case of giant retroperitoneal lipoma in a 32-year-old white female, with a history of pain and an abdominal mass over a 2-year period. Total abdominal ultrasonography and barium enema showed a large mass located in the retroperitoneal space behind the ascending colon. Laparotomy showed a large encapsulated tumor measuring 20 x 13 x 10 cm and weighing 3.400 g. The histological study revealed a benign neoplasm of fatty cells. CONCLUSION: The patient remains well 17 years after surgery, without recurrentce of the disease.RACIONAL: O lipoma é a neoplasia mesenquimal mais freqüente, raramente localizada no retroperitônio. Na maioria das vezes, o diagnóstico diferencial pré-operatório com os lipossarcomas de baixo grau de malignidade é difícil de ser estabelecido. OBJETIVO: Apresentar um caso de lipoma gigante retroperitoneal em mulher de 32 anos que há 2 anos apresentava história de dor e tumor abdominal palpável. A ultra-sonografia abdominal e o enema opaco mostraram grande massa localizada no retroperitônio, que deslocava o ceco e o cólon ascendente. A laparotomia mostrou tumor encapsulado com 20 x 13 x 10 cm e 3.400 g de peso. O estudo histopatológico mostrou presença de lipoma retroperitonial. A paciente encontra-se bem, sem recidiva da doença, 17 anos após a cirurgia.

  9. Increase in tracheal investment with beetle size supports hypothesis of oxygen limitation on insect gigantism.

    Science.gov (United States)

    Kaiser, Alexander; Klok, C Jaco; Socha, John J; Lee, Wah-Keat; Quinlan, Michael C; Harrison, Jon F

    2007-08-07

    Recent studies have suggested that Paleozoic hyperoxia enabled animal gigantism, and the subsequent hypoxia drove a reduction in animal size. This evolutionary hypothesis depends on the argument that gas exchange in many invertebrates and skin-breathing vertebrates becomes compromised at large sizes because of distance effects on diffusion. In contrast to vertebrates, which use respiratory and circulatory systems in series, gas exchange in insects is almost exclusively determined by the tracheal system, providing a particularly suitable model to investigate possible limitations of oxygen delivery on size. In this study, we used synchrotron x-ray phase-contrast imaging to visualize the tracheal system and quantify its dimensions in four species of darkling beetles varying in mass by 3 orders of magnitude. We document that, in striking contrast to the pattern observed in vertebrates, larger insects devote a greater fraction of their body to the respiratory system, as tracheal volume scaled with mass1.29. The trend is greatest in the legs; the cross-sectional area of the trachea penetrating the leg orifice scaled with mass1.02, whereas the cross-sectional area of the leg orifice scaled with mass0.77. These trends suggest the space available for tracheae within the leg may ultimately limit the maximum size of extant beetles. Because the size of the tracheal system can be reduced when oxygen supply is increased, hyperoxia, as occurred during late Carboniferous and early Permian, may have facilitated the evolution of giant insects by allowing limbs to reach larger sizes before the tracheal system became limited by spatial constraints.

  10. Gigantic jets produced by an isolated tropical thunderstorm near Réunion Island

    Science.gov (United States)

    Soula, Serge; van der Velde, Oscar; Montanya, Joan; Huet, Patrice; Barthe, Christelle; Bór, József

    2011-10-01

    Five gigantic jets (GJs) have been recorded with video and photograph cameras on 7 March 2010 above an isolated tropical storm east of Réunion Island. Three of them were produced before the storm reached its coldest cloud top temperature (approximately -81°C), and two others occurred during the cloud extension. Thanks to the close distance of observation (˜50 km), the luminosity within the cloud was recorded, and the events are analyzed in unprecedented detail. The tops of the GJs are estimated between 80 and 90 km. All these GJs are accompanied by long, continuous cloud illumination, and they are preceded and followed by intermittent optical flashes from the cloud, most of time without any cloud-to-ground (CG) flash simultaneously detected, which suggests they originated mainly as intracloud discharges and without any charge transfer to Earth. The CG lightning activity is observed to cease a few tens of seconds before the jets. According to ELF data recorded at Nagycenk, Hungary, the five GJs serve to raise negative charge. Their duration ranges from 333 to 850 ms. The leading jet has the most variable duration (33-167 ms) and propagates faster at higher altitudes. The trailing jet exhibits a continuous decrease of luminosity in different parts of the jet (lower channel, transition zone and, for most events, carrot sprite-like top) and in the cloud, with possible rebrightening. The lower channels (˜20-40 km altitude) produce blue luminosity which decreases with altitude and become more and more diffuse with time. The transition zone (around 40-65 km) consists of bright red, luminous beads slowly going up (˜104 m s-1), retracing the initial leading jet channels.

  11. High-precision chronology for Central American maize diversification from El Gigante rockshelter, Honduras.

    Science.gov (United States)

    Kennett, Douglas J; Thakar, Heather B; VanDerwarker, Amber M; Webster, David L; Culleton, Brendan J; Harper, Thomas K; Kistler, Logan; Scheffler, Timothy E; Hirth, Kenneth

    2017-08-22

    The first steps toward maize ( Zea mays subspecies mays ) domestication occurred in the Balsas region of Mexico by ∼9,000 calendar years B.P. (cal B.P.), but it remains unclear when maize was productive enough to be a staple grain in the Americas. Molecular and microbotanical data provide a partial picture of the timing and nature of morphological change, with genetic data indicating that alleles for some domestication traits were not yet fixed by 5,300 cal B.P. in the highlands of Mexico. Here, we report 88 radiocarbon dates on the botanical remains from El Gigante rockshelter (Honduras) to establish a Bayesian chronology over the past ∼11,000 y spanning the transition to maize-based food production. Botanical remains are remarkably well preserved and include over 10,000 maize macrofossils. We directly dated 37 maize cobs to establish the appearance and local change of maize at the site. Cobs are common in deposits dating between 4,340 and 4,020 cal B.P., and again between 2,350 and 980 cal B.P. The earliest cobs appear robustly domesticated, having 10-14 rows, suggesting strong selection for increased yield. The later cobs are comparable to these earliest ones, but show clear emergence of diverse traits, including increased cob width, rachis segment length, and cupule width. Our results indicate that domesticated landraces of maize productive enough to be a staple grain existed in Central America by 4,300 cal B.P.

  12. Transsphenoidal surgery for pituitary gigantism and galactorrhea in a 3.5 year old child.

    Science.gov (United States)

    Flitsch, J; Lüdecke, D K; Stahnke, N; Wiebel, J; Saeger, W

    2000-05-01

    The management of pituitary macroadenomas which lead to gigantism may require multiple therapeutical approaches, including medical treatment, surgery, and radiation therapy. Transsphenoidal surgery (TSS) during early childhood that achieves total removal of a growth hormone (GH) secreting tumor is rarely reported. The surgeon is confronted with special problems regarding the infantile anatomy. In this case, a 3.5 year old child, the youngest successfully treated by TSS so far, suffered from a GH- and prolactin (PRL) secreting macroadenoma of the pituitary gland. The girl initially presented with an increasing growth rate, later with breast development, and finally, at the age of 2.8 years, with galactorrhea and secretion of blood from the nipples. Increased levels of GH [122 micrograms/l], insulin-like growth factor (IGF-1) [830 micrograms/l], insulin-like growth factor binding protein 3 (IGFBP-3) [8.6 mg/l] and PRL [590 micrograms/l] were found. MRI scans revealed a macroadenoma of 2.7 cm diameter. An eight-week trial of relatively low dose dopamine agonists led to a reduction of PRL, while the GH- and IGF-1 levels remained unchanged; the tumor showed only little shrinkage. Since there was chiasma compression, we opted for early TSS. A complete tumor removal was achieved despite the difficulties of a narrow approach. After TSS, low levels of GH, IGF-1, and PRL documented a complete tumor removal, but persistent diabetes insipidus and anterior lobe deficits resulted from surgery. In summary, if primary medical therapy alone is unable to adequately reduce hormone hypersecretion and tumor size in early childhood, TSS is recommended. Thus, radiation therapy may be reserved for surgical failure.

  13. Irradiated bivalve mollusks: Use of EPR spectroscopy for identification and dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Alberti, Angelo, E-mail: aalberti@isof.cnr.it [CNR-ISOF, Area della Ricerca di Bologna, Via P. Gobetti 101, Bologna I-40129 (Italy); Chiaravalle, Eugenio [Istituto Zooprofilattico Sperimentale della Puglia e Basilicata, Via Manfredonia 20, Foggia I-71100 (Italy); Fuochi, Piergiorgio; Macciantelli, Dante [CNR-ISOF, Area della Ricerca di Bologna, Via P. Gobetti 101, Bologna I-40129 (Italy); Mangiacotti, Michele, E-mail: michelemangiacotti@libero.it [Istituto Zooprofilattico Sperimentale della Puglia e Basilicata, Via Manfredonia 20, Foggia I-71100 (Italy); Marchesani, Giuliana [Istituto Zooprofilattico Sperimentale della Puglia e Basilicata, Via Manfredonia 20, Foggia I-71100 (Italy); Plescia, Elena [CNR-ISOF, Area della Ricerca di Bologna, Via P. Gobetti 101, Bologna I-40129 (Italy)

    2011-12-15

    High energy radiation treatment of foodstuff for microbial control and shelf-life extension is being used in many countries. However, for consumer protection and information, the European Union has adopted the Directives 1999/2/EC and 1999/3/EC to harmonize the rules concerning the treatment and trade of irradiated foods in EU countries. Among the validated methods to detect irradiated foods the EU directives also include Electron Paramagnetic Resonance (EPR/ESR) spectroscopy. We describe herein the use of EPR for identification of four species of bivalve mollusks, i.e. brown Venus shells (Callista chione), clams (Tapes semidecussatus), mussels (Mytilus galloprovincialis) and oysters (Ostrea edulis) irradiated with {sup 60}Co {gamma}-rays. EPR could definitely identify irradiated seashells due to the presence of long-lived free radicals, primarily CO{sub 2}{sup -}, CO{sub 3}{sup 3-}, SO{sub 2}{sup -} and SO{sub 3}{sup -} radical anions. The presence of other organic free radicals, believed to originate from conchiolin, a scleroprotein present in the shells, was also ascertained. The use of one of these radicals as a marker for irradiation of brown Venus shells and clams can be envisaged. We also propose a dosimetric protocol for the reconstruction of the administered dose in irradiated oysters. - Highlights: > EPR spectroscopy is confirmed a valuable identification tool for irradiated mollusks. > A conchiolin-derived radical can be used as irradiation marker for some mollusks. > A reliable protocol is outlined for dose reconstruction of irradiated oysters.

  14. Facultative parasitism by the bivalve Kurtiella pedroana in the sand crab Emerita analoga

    Science.gov (United States)

    Bhaduri, Ritin; Valentich-Scott, Paul; Hilgers, Mark; Singh, Rajvir; Hickman, Mikaila; Lafferty, Kevin D.

    2017-01-01

    It is rare that an organism capable of independent or commensalistic existence can also become endoparasitic on a host. In this study, we documented a potential step toward parasitism in the commensal clam Kurtiella pedroana (Bivalvia: Galeommatoidea). Galeommatoideans are known commensals of various invertebrates, including crustaceans. Emerita analoga (Decapoda: Hippidae) is an abundant intertidal decapod inhabiting sandy beaches of the Pacific coast of North and South America. Crabs collected from Monterey Bay, California, were measured and examined externally and internally for associated molluscs. Out of the 520 crabs, 37 large female individuals harbored 49 bivalves (prevalence of 7.11% and mean intensity of 1.3). Forty-one ectocommensal clams were either inside the crab's branchial chambers or on their lateroventral surfaces, and were attached by byssal threads. Our key finding was eight clams that lacked byssal threads and were living in the hemocoel. These internal clams were significantly smaller than the ectocommensals. Because these internal clams lacked access to their normal food, we hypothesize they might have fed on their host's hemolymph as would a parasite. This clam species likely can't reproduce inside its host, implying that endoparasitism is a dead-end state for K. pedroana. Facultative parasitism in a free-living or an ectocommensal is uncommon and suggests a pathway to parasitism.

  15. Physiological status and intersex in the endobenthic bivalve Scrobicularia plana from thirteen estuaries in northwest France

    International Nuclear Information System (INIS)

    Fossi Tankoua, O.; Amiard-Triquet, C.; Denis, F.; Minier, C.; Mouneyrac, C.; Berthet, B.

    2012-01-01

    The bivalve Scrobicularia plana, an important species for the structure and functioning of estuarine and coastal mudflats, was studied in thirteen sites from NW France differing by their degree of contamination to document the presence of reproduction impairments (intersex, sex ratio, gonadosomatic indices) in relation to the condition revealed by using hepatosomatic and condition indices. In agreement with recent studies in other European estuaries, intersex was revealed in all the studied estuaries, including sites the chemical and ecological status of which is considered “good” according to the criteria of the European Water Framework Directive. The presence of endocrine disrupting chemicals (EDCs) could result in such disturbances. Our results re-inforce the concern linked to the subtle effects of EDCs, which are active at very low doses, often in the absence of any major sign of toxicity. However at this stage, no clear link may be established between intersex and population effects. - Highlights: ► Clams were collected from 13 estuaries differing by their degree of contamination. ► Gonadosomatic, hepatosomatic and condition indices were determined. ► Reproduction impairments (intersex, biased sex ratio, asynchronism) were shown. ► Intersex shown even at sites with good ecological status (Water Framework Directive). ► No clear links between intersex and populational effects. - Intersex in clams from estuaries, the chemical/ecological status of which was considered as good under the EC Water Framework Directive.

  16. The bivalve Anopaea (Inoceramidae) from the Upper Jurassic-lowermost Cretaceous of Mexico

    Science.gov (United States)

    Zell, Patrick; Crame, J. Alistair; Stinnesbeck, Wolfgang; Beckmann, Seija

    2015-07-01

    In Mexico, the Upper Jurassic to lowermost Cretaceous La Casita and coeval La Caja and La Pimienta formations are well-known for their abundant and well-preserved marine vertebrates and invertebrates. The latter include conspicuous inoceramid bivalves of the genus Anopaea not formally described previously from Mexico. Anopaea bassei (Lecolle de Cantú, 1967), Anopaea cf. stoliczkai (Holdhaus, 1913), Anopaea cf. callistoensis Crame and Kelly, 1995 and Anopaea sp. are rare constituents in distinctive Tithonian-lower Berriasian levels of the La Caja Formation and one Tithonian horizon of the La Pimienta Formation. Anopaea bassei was previously documented from the Tithonian of central Mexico and Cuba, while most other members of Anopaea described here are only known from southern high latitudes. The Mexican assemblage also includes taxa which closely resemble Anopaea stoliczkai from the Tithonian of India, Indonesia and the Antarctic Peninsula, and Anopaea callistoensis from the late Tithonian to ?early Berriasian of the Antarctic Peninsula. Our new data expand the palaeogeographical distribution of the high latitude Anopaea to the Gulf of Mexico region and substantiate faunal exchange, in the Late Jurassic-earliest Cretaceous, between Mexico and the Antarctic Realm.

  17. The Shell of the Invasive Bivalve Species Dreissena polymorpha: Biochemical, Elemental and Textural Investigations.

    Directory of Open Access Journals (Sweden)

    Françoise Immel

    Full Text Available The zebra mussel Dreissena polymorpha is a well-established invasive model organism. Although extensively used in environmental sciences, virtually nothing is known of the molecular process of its shell calcification. By describing the microstructure, geochemistry and biochemistry/proteomics of the shell, the present study aims at promoting this species as a model organism in biomineralization studies, in order to establish a bridge with ecotoxicology, while sketching evolutionary conclusions. The shell of D. polymorpha exhibits the classical crossed-lamellar/complex crossed lamellar combination found in several heterodont bivalves, in addition to an external thin layer, the characteristics of which differ from what was described in earlier publication. We show that the shell selectively concentrates some heavy metals, in particular uranium, which predisposes D. polymorpha to local bioremediation of this pollutant. We establish the biochemical signature of the shell matrix, demonstrating that it interacts with the in vitro precipitation of calcium carbonate and inhibits calcium carbonate crystal formation, but these two properties are not strongly expressed. This matrix, although overall weakly glycosylated, contains a set of putatively calcium-binding proteins and a set of acidic sulphated proteins. 2D-gels reveal more than fifty proteins, twenty of which we identify by MS-MS analysis. We tentatively link the shell protein profile of D. polymorpha and the peculiar recent evolution of this invasive species of Ponto-Caspian origin, which has spread all across Europe in the last three centuries.

  18. Intrinsic hierarchical structural imperfections in a natural ceramic of bivalve shell with distinctly graded properties.

    Science.gov (United States)

    Jiao, Da; Liu, Zengqian; Zhang, Zhenjun; Zhang, Zhefeng

    2015-07-22

    Despite the extensive investigation on the structure of natural biological materials, insufficient attention has been paid to the structural imperfections by which the mechanical properties of synthetic materials are dominated. In this study, the structure of bivalve Saxidomus purpuratus shell has been systematically characterized quantitatively on multiple length scales from millimeter to sub-nanometer. It is revealed that hierarchical imperfections are intrinsically involved in the crossed-lamellar structure of the shell despite its periodically packed platelets. In particular, various favorable characters which are always pursued in synthetic materials, e.g. nanotwins and low-angle misorientations, have been incorporated herein. The possible contributions of these imperfections to mechanical properties are further discussed. It is suggested that the imperfections may serve as structural adaptations, rather than detrimental defects in the real sense, to help improve the mechanical properties of natural biological materials. This study may aid in understanding the optimizing strategies of structure and properties designed by nature, and accordingly, provide inspiration for the design of synthetic materials.

  19. Draft Genome of the Pearl Oyster Pinctada fucata: A Platform for Understanding Bivalve Biology

    Science.gov (United States)

    Takeuchi, Takeshi; Kawashima, Takeshi; Koyanagi, Ryo; Gyoja, Fuki; Tanaka, Makiko; Ikuta, Tetsuro; Shoguchi, Eiichi; Fujiwara, Mayuki; Shinzato, Chuya; Hisata, Kanako; Fujie, Manabu; Usami, Takeshi; Nagai, Kiyohito; Maeyama, Kaoru; Okamoto, Kikuhiko; Aoki, Hideo; Ishikawa, Takashi; Masaoka, Tetsuji; Fujiwara, Atushi; Endo, Kazuyoshi; Endo, Hirotoshi; Nagasawa, Hiromichi; Kinoshita, Shigeharu; Asakawa, Shuichi; Watabe, Shugo; Satoh, Nori

    2012-01-01

    The study of the pearl oyster Pinctada fucata is key to increasing our understanding of the molecular mechanisms involved in pearl biosynthesis and biology of bivalve molluscs. We sequenced ∼1150-Mb genome at ∼40-fold coverage using the Roche 454 GS-FLX and Illumina GAIIx sequencers. The sequences were assembled into contigs with N50 = 1.6 kb (total contig assembly reached to 1024 Mb) and scaffolds with N50 = 14.5 kb. The pearl oyster genome is AT-rich, with a GC content of 34%. DNA transposons, retrotransposons, and tandem repeat elements occupied 0.4, 1.5, and 7.9% of the genome, respectively (a total of 9.8%). Version 1.0 of the P. fucata draft genome contains 23 257 complete gene models, 70% of which are supported by the corresponding expressed sequence tags. The genes include those reported to have an association with bio-mineralization. Genes encoding transcription factors and signal transduction molecules are present in numbers comparable with genomes of other metazoans. Genome-wide molecular phylogeny suggests that the lophotrochozoan represents a distinct clade from ecdysozoans. Our draft genome of the pearl oyster thus provides a platform for the identification of selection markers and genes for calcification, knowledge of which will be important in the pearl industry. PMID:22315334

  20. Marine Bacteria with antimicrobials capacity isolated from cultures of bivalve mollusks

    Directory of Open Access Journals (Sweden)

    Fabiola Pellon

    2014-06-01

    Full Text Available Microorganisms have commonly been studied as producers of antibacterial substances; yet they are also considered producers of antifungic, antiviral, antiparasitic, citotoxics and inhibitory of other forms of cellular growth substances. This paper describes the isolation, inhibitory potential and phenotipic characterization of native bacterial strains associated to bivalve mollusks such as Argopecten purpuratus “concha de abanico” and Crassostrea gigas “ostra” in cultivation systems. From 345 marine strains collected, 20 strains were recovered that had the ability of inhibiting a wide spectrum of fish, mollusks and shellfish pathogenic bacteria; being the most sensitive pathogens Aeromonas sobria P-281, Aeromonas hydrophila ATCC 7966, Vibrio vulnificus ATCC 27562 and Vibrio parahaemolyticus ATCC 17803. The phenotipic characterization of this strains with inhibitory capacity allowed the identification of the following genera: Vibrio (40%, Aeromonas (15%, Flavobacterium (10%, Pseudomonas (5%, Moraxella (5%, Flexibacter (5%. A 20% could not be identified. The results suggest that the isolated bacteria could be used as probiotics agents for the biological control of pathogens from marine organisms of interest in mariculture.

  1. Mobile Element Evolution Playing Jigsaw—SINEs in Gastropod and Bivalve Mollusks

    Science.gov (United States)

    Matetovici, Irina; Sajgo, Szilard; Ianc, Bianca; Ochis, Cornelia; Bulzu, Paul; Popescu, Octavian; Damert, Annette

    2016-01-01

    SINEs (Short INterspersed Elements) are widely distributed among eukaryotes. Some SINE families are organized in superfamilies characterized by a shared central domain. These central domains are conserved across species, classes, and even phyla. Here we report the identification of two novel such superfamilies in the genomes of gastropod and bivalve mollusks. The central conserved domain of the first superfamily is present in SINEs in Caenogastropoda and Vetigastropoda as well as in all four subclasses of Bivalvia. We designated the domain MESC (Romanian for MElc—snail and SCoica—mussel) because it appears to be restricted to snails and mussels. The second superfamily is restricted to Caenogastropoda. Its central conserved domain—Snail—is related to the Nin-DC domain. Furthermore, we provide evidence that a 40-bp subdomain of the SINE V-domain is conserved in SINEs in mollusks and arthropods. It is predicted to form a stable stem-loop structure that is preserved in the context of the overall SINE RNA secondary structure in invertebrates. Our analysis also recovered short retrotransposons with a Long INterspersed Element (LINE)-derived 5′ end. These share the body and/or the tail with transfer RNA (tRNA)-derived SINEs within and across species. Finally, we identified CORE SINEs in gastropods and bivalves—extending the distribution range of this superfamily. PMID:26739168

  2. Effect of the alien invasive bivalve Corbicula fluminea on the nutrient dynamics under climate change scenarios

    Science.gov (United States)

    Coelho, J. P.; Lillebø, A. I.; Crespo, D.; Leston, S.; Dolbeth, M.

    2018-05-01

    The main aim of this study was to evaluate the impact of the alien invasive bivalve Corbicula fluminea (Müller, 1774) in the nutrient dynamics of temperate estuarine systems (oligohaline areas) under climate change scenarios. The scenarios simulated shifts in climatic conditions, following salinity (0 or 5) and temperature (24 or 30 °C) changes, usual during drought and heat wave events. The effect of the individual size/age (different size classes with fixed biomass) and density (various densities of <1 cm clams) on the bioturbation-associated nutrient dynamics were also evaluated under an 18-day laboratory experimental setup. Results highlight the significant effect of C. fluminea on the ecosystem nutrient dynamics, enhancing the efflux of both phosphate and dissolved inorganic nitrogen (DIN) from the sediments to the water column. Both drought and heat wave events will have an impact on the DIN dynamics within C. fluminea colonized systems, favouring a higher NH4-N efflux. The population structure of C. fluminea will have a decisive role on the impact of the species, with stronger nutrient effluxes associated with a predominantly juvenile population structure.

  3. North Atlantic Oscillation dynamics recorded in shells of a long-lived bivalve mollusk

    Science.gov (United States)

    Schöne, Bernd R.; Oschmann, Wolfgang; Rössler, Jochen; Freyre Castro, Antuané D.; Houk, Stephen D.; Kröncke, Ingrid; Dreyer, Wolfgang; Janssen, Ronald; Rumohr, Heye; Dunca, Elena

    2003-12-01

    Existing reconstructions of the winter North Atlantic Oscillation (WNAO) are based on terrestrial proxies and historical documents. No direct high-resolution, long-term rec ords from marine settings are available for this major climate-dictating phenomenon, which severely affects a variety of economic aspects of our society. Here we present a 245 yr proxy WNAO index based on shells of the long-lived marine bivalve mollusk Arctica islandica. Variations in annual rates of shell growth are positively correlated with WNAO-related changes in the food supply. Maximum amplitudes in frequency bands of 7 9 and 5 7 yr fall exactly within the range of instrumental and other proxy WNAO indices. These estimates were obtained for specimens collected live, 2000 km apart, in the central North Sea and on the Norwegian Shelf. Hence, the WNAO influences hydrographic regimes of large regions of the ocean. Our study demonstrates that A. islandica can reliably reconstruct WNAO dynamics for time intervals and regions without instrumental records. Our new tool functions as a proxy for the WNAO index prior to the twentieth-century greenhouse forcing and has the potential to further validate other proxy-based WNAO records.

  4. Polonium-210 in marine bivalves inhabiting a wedge bank region, South India

    International Nuclear Information System (INIS)

    Feroz Khan, M.; Godwin Wesley, S.; Rajan, M.P.

    2013-01-01

    Determination of background radiation dose-rate is important in the process of assessing risks to the environment from exposure to living organisms both in terms of deriving the incremental dose-rate and as a point of reference for evaluating the significance of the exposure level. In the present study, 210 Po was quantified in two species of bivalve mollusks commonly available from so called a 'wedge bank region' of southern tip of India. Based on the activity concentration in media and in the whole body, an external and internal dose rate assessment to green mussel Perna viridis and brown mussel Perna indica due to 210 Po was derived using ERICA assessment tool. The samples were collected at the intertidal region along the wedge bank region of southern tip of India during 2009 to 2010. The measurement contributes to a better knowledge of these elements, since no data exists in this region. 5-10 g of each tissue sample was wet-digested using 70% concentrated HNO 3 followed by the addition of 40% H 2 O 2 along with 20 8Po tracer (0.2 Bq). The normality of the data set was checked using Lilliefors test (ne''50) and potential outliers, if any, were tested using Walsh's test (n>60). Using the measured 210 Po activity in molluscs, sediments and seawater, dose assessment was performed using the Tier 2 ERICA environment dose assessment tool 1.0

  5. Gigantic transverse voltage induced via off-diagonal thermoelectric effect in CaxCoO2 thin films

    Science.gov (United States)

    Takahashi, Kouhei; Kanno, Tsutomu; Sakai, Akihiro; Adachi, Hideaki; Yamada, Yuka

    2010-07-01

    Gigantic transverse voltages exceeding several tens volt have been observed in CaxCoO2 thin films with tilted c-axis orientation upon illumination of nanosecond laser pulses. The voltage signals were highly anisotropic within the film surface showing close relation with the c-axis tilt direction. The magnitude and the decay time of the voltage strongly depended on the film thickness. These results confirm that the large laser-induced voltage originates from a phenomenon termed the off-diagonal thermoelectric effect, by which a film out-of-plane temperature gradient leads to generation of a film in-plane voltage.

  6. Aggressive tumor growth and clinical evolution in a patient with X-linked acro-gigantism syndrome.

    OpenAIRE

    Naves, Luciana A.; Daly, Adrian Francis; Dias, Luiz Augusto; Yuan, Bo; Zakir, Juliano Coelho Oliveira; Barra, Gustavo Barcellos; Palmeira, Leonor; Villa, Chiara; Trivellin, Giampaolo; Junior, Armindo Jreige; Neto, Florencio Figueiredo Cavalcante; Liu, Pengfei; Pellegata, Natalia S.; Stratakis, Constantine A.; Lupski, James R.

    2016-01-01

    X-linked acro-gigantism (X-LAG) syndrome is a newly described disease caused by microduplications on chromosome Xq26.3 leading to copy number gain of GPR101. We describe the clinical progress of a sporadic male X-LAG syndrome patient with an Xq26.3 microduplication, highlighting the aggressive natural history of pituitary tumor growth in the absence of treatment. The patient first presented elsewhere aged 5 years 8 months with a history of excessive growth for >2 years. His height was 163 cm,...

  7. A novel germline mutation in the aryl hydrocarbon receptor-interacting protein (AIP) gene in an Italian family with gigantism.

    Science.gov (United States)

    Urbani, C; Russo, D; Raggi, F; Lombardi, M; Sardella, C; Scattina, I; Lupi, I; Manetti, L; Tomisti, L; Marcocci, C; Martino, E; Bogazzi, F

    2014-10-01

    Acromegaly usually occurs as a sporadic disease, but it may be a part of familial pituitary tumor syndromes in rare cases. Germline mutations in the aryl hydrocarbon receptor-interacting protein (AIP) gene have been associated with a predisposition to familial isolated pituitary adenoma. The aim of the present study was to evaluate the AIP gene in a patient with gigantism and in her relatives. Direct sequencing of AIP gene was performed in fourteen members of the family, spanning among three generations. The index case was an 18-year-old woman with gigantism due to an invasive GH-secreting pituitary adenoma and a concomitant tall-cell variant of papillary thyroid carcinoma. A novel germline mutation in the AIP gene (c.685C>T, p.Q229X) was identified in the proband and in two members of her family, who did not present clinical features of acromegaly or other pituitary disorders. Eleven subjects had no mutation in the AIP gene. Two members of the family with clinical features of acromegaly refused either the genetic or the biochemical evaluation. The Q229X mutation was predicted to generate a truncated AIP protein, lacking the last two tetratricopeptide repeat domains and the final C-terminal α-7 helix. We identified a new AIP germline mutation predicted to produce a truncated AIP protein, lacking its biological properties due to the disruption of the C-terminus binding sites for both the chaperones and the client proteins of AIP.

  8. Pelletization of seeds of Raphanus sativus L. cv. Redondo Gigante with graphite for germination under water stress conditions

    Directory of Open Access Journals (Sweden)

    Nobel Penteado Freitas

    2000-01-01

    Full Text Available The effect of water stress on germination of radish seeds is dependent on the presence of light. The effect of pelletization of radish seeds with powdered graphite on the tolerance to water stress under light was analysed. White light and far-red lights were filtered by graphite increasing slightly the tolerance of pelleted seeds to water stress of -0.77MPa. Although red light also inhibited seed germination the graphite had no effect. We propose the pelletization of seeds of Raphanus sativus, at least in cv redondo gigante with graphite as a pratice before planting to increase the tolerance to water stress.O efeito do estresse hídrico é dependente da presença de luz em sementes de rabanete. O efeito da peletização com grafite em pó foi analisado. Luz branca e vermelho-extremo são filtradas pelo grafite aumentando parcialmente a tolerância ao estresse hídrico de -0,77MPa em sementes peletizadas. Embora a luz vermelha também iniba a germinação em condições de estresse a peletização não teve efeito. Nós propomos a peletização de sementes de Raphanus saivus L. cv. redondo gigante como uma prática antes do plantio para aumentar a tolerância ao estresse hídrico.

  9. Near infra-red spectroscopy quantitative modelling of bivalve protein, lipid and glycogen composition using single-species versus multi-species calibration and validation sets

    Science.gov (United States)

    Bartlett, Jill K.; Maher, William A.; Purss, Matthew B. J.

    2018-03-01

    Near infrared spectroscopy (NIRS) quantitative modelling was used to measure the protein, lipid and glycogen composition of five marine bivalve species (Saccostrea glomerata, Ostrea angasi, Crassostrea gigas, Mytilus galloprovincialis and Anadara trapezia) from multiple locations and seasons. Predictive models were produced for each component using individual species and aggregated sample populations for the three oyster species (S. glomerata, O. angasi and C. gigas) and for all five bivalve species. Whole animal tissues were freeze dried, ground to > 20 μm and scanned by NIRS. Protein, lipid and glycogen composition were determined by traditional chemical analyses and calibration models developed to allow rapid NIRS-measurement of these components in the five bivalve species. Calibration modelling was performed using wavelet selection, genetic algorithms and partial least squares analysis. Model quality was assessed using RPIQ and RMESP. For protein composition, single species model results had RPIQ values between 2.4 and 3.5 and RMSEP between 8.6 and 18%, the three oyster model had an RPIQ of 2.6 and an RMSEP of 10.8% and the five bivalve species had an RPIQ of 3.6 and RMSEP of 8.7% respectively. For lipid composition, single species models achieved RPIQ values between 2.9 and 5.3 with RMSEP between 9.1 and 11.2%, the oyster model had an RPIQ of 3.6 and RMSEP of 6.8 and the five bivalve model had an RPIQ of 5.2 and RMSEP of 6.8% respectively. For glycogen composition, the single species models had RPIQs between 3.8 and 18.9 with RMSEP between 3.5 and 9.2%, the oyster model had an RPIQ of 5.5 and RMSEP of 7.1% and the five bivalve model had an RPIQ of 4 and RMSEP of 7.6% respectively. Comparison between individual species models and aggregated models for three oyster species and five bivalve species for each component indicate that aggregating data from like species produces high quality models with robust and reliable quantitative application. The benefit of

  10. Congener-specific distribution and bioaccumulation of short-chain chlorinated paraffins in sediments and bivalves of the Bohai Sea, China.

    Science.gov (United States)

    Ma, Xindong; Chen, Chen; Zhang, Haijun; Gao, Yuan; Wang, Zhen; Yao, Ziwei; Chen, Jiping; Chen, Jingwen

    2014-02-15

    Short-chain chlorinated paraffins (SCCPs) are a new type of persistent organic pollutants that are of great environmental concern because of their wide distribution. In this study, surface sediments and bivalve samples were collected from the coastal area of the Bohai Sea in China. Total SCCP (ΣSCCP) concentrations in surface sediments and bivalves ranged from 97.4 ng g(-1) dry weight (dw) to 1756.7 ng g(-1) dw and 476.4-3269.5 ng g(-1) dw, respectively. C10-CPs and C11-CPs were the predominant homologue groups in all sediments and bivalves. Specific congener composition analysis and correspondence analysis indicated that the local SCCP source mainly came from CP-42 and CP-52 products, and riverine input had an important function. The biota-sediment accumulation factors of ΣSCCPs for bivalves ranged from 1.08 to 1.61, and a significant correlation indicated that the SCCP congener with higher chlorination degree was more likely to be accumulated in bivalves. Copyright © 2014. Published by Elsevier Ltd.

  11. Razanandrongobe sakalavae, a gigantic mesoeucrocodylian from the Middle Jurassic of Madagascar, is the oldest known notosuchian

    Directory of Open Access Journals (Sweden)

    Cristiano Dal Sasso

    2017-07-01

    this gigantic predator is also attempted here. The very robust jaw bones of R. sakalavae, coupled with its peculiar dentition, strongly suggest a diet that included hard tissue such as bone and tendon.

  12. Paraganglioma pré-aórtico gigante Giant preaortic paraganglioma

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    Sergio Renato Pais Costa

    2008-12-01

    Full Text Available INTRODUÇÃO: O paraganglioma é um tumor neuroendócrino raro que ocorre mais frequentemente em adultos jovens. Geralmente produz catecolaminas acarretando síndrome adrenérgica. No entanto, muito raramente, quando não-funcionante seus sintomas são mais frequentemente associados à massa abdominal ou mesmo dor. Nessas circunstâncias costumam representar diagnóstico difícil sendo confundidos com os sarcomas de retroperitônio. RELATO DO CASO: Paraganglioma pré-aórtico gigante não-funcionante em paciente com níveis baixos de catecolaminas (sérico e urinário. O diagnóstico pré-operatório foi dado por tomografia computadorizada, onde foi observada massa sólida, hipervascular com calcificações e área cística central. O paciente foi submetido à ressecção cirúrgica da massa com boa evolução pós-operatória. Um ano após a operação, o doente encontra-se vivo sem recidiva tumoral. CONCLUSÃO: Em que pese a raridade o paraganglioma pré-aortico não-funcionante deve ser lembrado com diagnóstico diferencial com os sarcomas de retroperitônio. Seu tratamento é cirúrgico e apresenta bom prognóstico.RACIONAL: Paraganglioma is a rare neuroendocrine tumor which often diagnosed in the young adult. Generally, paraganglioma produces catecholamines causing adrenergic syndrome. However, more rarely when tumor is nonfunctioning, their symptoms are more associated with an abdominal mass or even pain. In these circumstances, paraganglioma present a difficult diagnosis confounding with retroperitoneal sarcomas. CASE REPORT: The authors present a case of nonfunctioning giant preaortic paraganglioma. This patient had low levels of catecholamines (both seric and urinary. The preoperative diagnosis was done by means computed tomography. This lesion presented as well-vascularized tumor with calcifications and necrotic central area. The patient underwent a surgical resection with good postoperative outcome. To date, one year after surgical

  13. Climatic control on the growth of gigantic gypsum crystals within hypogenic caves (Naica mine, Mexico)?

    Science.gov (United States)

    Garofalo, Paolo S.; Fricker, Mattias B.; Günther, Detlef; Forti, Paolo; Mercuri, Anna-Maria; Loreti, Mara; Capaccioni, Bruno

    2010-01-01

    Three hypogenic caves within the Naica mine of Mexico ( Cueva de los Cristales — CLC, Ojo de la Reina — OR, and Cueva de las Velas — CLV) host spectacular gypsum crystals up to 11 m in length. These caves are close to another shallow cave of the area ( Cueva de las Espadas — CLE), with which they cover a 160 m-deep vertical section of the local drainage basin. Similar to other hypogenic caves, all these caves lack a direct connection with the land surface and should be unrelated with climate. A record of multi-technique fluid inclusion data and pollen spectra from cave and mine gypsum indicates surprisingly that climatic changes occurring at Naica could have controlled fluid composition in these caves, and hence crystal growth. Microthermometry and LA-ICP-Mass Spectrometry of fluid inclusions indicate that the shallow, chemically peculiar, saline fluid (up to 7.7 eq. wt.%NaCl) of CLE could have formed from evaporation, during a dry and hot climatic period. The fluid of the deep caves was instead of low salinity (˜ 3.5 eq. wt.% NaCl) and chemically homogeneous, and was poorly affected by evaporation. We propose that mixing of these two fluids, generated at different depths of the Naica drainage basin, determined the stable supersaturation conditions for the gigantic gypsum crystals to grow. Fluid mixing was controlled by the hydraulic communication between CLE and the other deep caves, and must have taken place during cycles of warm-dry and fresh-wet climatic periods, which are known to have occurred in the region. Pollen grains from a 35 ka-old gypsum crystal of CLC corresponds to a fairly homogenous catchment basin made of a mixed broadleaf wet forest, which suggests precipitation during a fresh-wet climatic period and confirms our interpretation of the fluid inclusion data. The unusual combination of geological and geochemical factors of Naica suggests that other hypogenic caves found elsewhere may not host similar crystals. However, this work shows that

  14. Rapid and repeated origin of insular gigantism and dwarfism in Australian tiger snakes.

    Science.gov (United States)

    Keogh, J Scott; Scott, Ian A W; Hayes, Christine

    2005-01-01

    It is a well-known phenomenon that islands can support populations of gigantic or dwarf forms of mainland conspecifics, but the variety of explanatory hypotheses for this phenomenon have been difficult to disentangle. The highly venomous Australian tiger snakes (genus Notechis) represent a well-known and extreme example of insular body size variation. They are of special interest because there are multiple populations of dwarfs and giants and the age of the islands and thus the age of the tiger snake populations are known from detailed sea level studies. Most are 5000-7000 years old and all are less than 10,000 years old. Here we discriminate between two competing hypotheses with a molecular phylogeography dataset comprising approximately 4800 bp of mtDNA and demonstrate that populations of island dwarfs and giants have evolved five times independently. In each case the closest relatives of the giant or dwarf populations are mainland tiger snakes, and in four of the five cases, the closest relatives are also the most geographically proximate mainland tiger snakes. Moreover, these body size shifts have evolved extremely rapidly and this is reflected in the genetic divergence between island body size variants and mainland snakes. Within south eastern Australia, where populations of island giants, populations of island dwarfs, and mainland tiger snakes all occur, the maximum genetic divergence is only 0.38%. Dwarf tiger snakes are restricted to prey items that are much smaller than the prey items of mainland tiger snakes and giant tiger snakes are restricted to seasonally available prey items that are up three times larger than the prey items of mainland tiger snakes. We support the hypotheses that these body size shifts are due to strong selection imposed by the size of available prey items, rather than shared evolutionary history, and our results are consistent with the notion that adaptive plasticity also has played an important role in body size shifts. We suggest

  15. Gigantic landslides versus glacial deposits: on origin of large hummock deposits in Alai Valley, Northern Pamir

    Science.gov (United States)

    Reznichenko, Natalya

    2015-04-01

    As glaciers are sensitive to local climate, their moraines position and ages are used to infer past climates and glacier dynamics. These chronologies are only valid if all dated moraines are formed as the result of climatically driven advance and subsequent retreat. Hence, any accurate palaeoenvironmental reconstruction requires thorough identification of the landform genesis by complex approach including geomorphological, sedimentological and structural landform investigation. Here are presented the implication of such approach for the reconstruction of the mega-hummocky deposits formation both of glacial and landslide origin in the glaciated Alai Valley of the Northern Pamir with further discussion on these and similar deposits validity for palaeoclimatic reconstructions. The Tibetan Plateau valleys are the largest glaciated regions beyond the ice sheets with high potential to provide the best geological record of glacial chronologies and, however, with higher probabilities of the numerous rock avalanche deposits including those that were initially considered of glacial origin (Hewitt, 1999). The Alai Valley is the largest intermountain depression in the upper reaches of the Amudarja River basin that has captured numerous unidentified extensive hummocky deposits descending from the Zaalai Range of Northern Pamir, covering area in more than 800 km2. Such vast hummocky deposits are usually could be formed either: 1) glacially by rapid glacial retreat due to the climate signal or triggered a-climatically glacial changes, such as glacial surge or landslide impact, or 2) during the landslide emplacement. Combination of sediment tests on agglomerates forming only in rock avalanche material (Reznichenko et al., 2012) and detailed geomorphological and sedimentological descriptions of these deposits allowed reconstructing the glacial deposition in the Koman and Lenin glacial catchments with identification of two gigantic rock avalanches and their relation to this glacial

  16. BIORREGULADORES NA MORFOLOGIA E NA PRODUTIVIDADE DE FRUTOS DE TOMATEIRO CULTIVAR ÂNGELA GIGANTE

    Directory of Open Access Journals (Sweden)

    MARTINS MARIA BERNARDETE GONÇALVES

    1997-01-01

    Full Text Available O presente trabalho teve como finalidade observar aspectos morfológicos dos frutos de tomateiro, Lycopersicon esculentum Mill. cv. Ângela Gigante, submetidos à ação de biorreguladores, com ou sem adubação adicional, e determinar as possíveis alterações na produtividade. Foram desenvolvidos, em casa de vegetação, em épocas distintas, dois ensaios. As mudas foram selecionadas e transplantadas para vasos com capacidade de 12 L de terra, contendo uma mistura de solo argiloso, areia, matéria orgânica e uma adubação mineral complementar de N, P, K. No segundo ensaio, após o transplante das mudas, além da adubação mineral complementar de N, P, K, efetuaram-se adubações adicionais (fertirrigação. Em ambos os ensaios, quando as plantas atingiram quatro folhas definitivas, realizaram-se as pulverizações com GA3 50 mg/L; NAA 100 mg/L; CCC 1.500 mg/L e SADH 3.000 mg/L. Realizaram-se, nos dois ensaios, quatro coletas de frutos maduros por planta. De modo geral, para o primeiro, o tratamento com CCC mostrou tendência em aumentar o número e a massa total de frutos por planta em relação à testemunha e aos demais tratamentos, enquanto o tratamento com NAA obteve efeito contrário. O ensaio com fertirrigação adicional não provocou alterações significativas na produção de frutos; no entanto, no tratamento com SADH, ocorreu maior incidência de anomalias. O tratamento com GA3 ocasionou, em alguns frutos, a maturação precoce da placenta em relação ao pericarpo e eventuais formações de frutos geminados. Não se observaram diferenças morfológicas significativas em relação ao comprimento e ao diâmetro médio de frutos provenientes do primeiro ensaio, porém frutos de plantas tratadas com CCC e de plantas testemunha, provindos do segundo ensaio, mostraram maior diâmetro.

  17. Molluscs for Sale: Assessment of Freshwater Gastropods and Bivalves in the Ornamental Pet Trade.

    Science.gov (United States)

    Ng, Ting Hui; Tan, Siong Kiat; Wong, Wing Hing; Meier, Rudolf; Chan, Sow-Yan; Tan, Heok Hui; Yeo, Darren C J

    2016-01-01

    The ornamental pet trade is often considered a key culprit for conservation problems such as the introduction of invasive species (including infectious diseases) and overharvesting of rare species. Here, we present the first assessment of the biodiversity of freshwater molluscs in the ornamental pet trade in Singapore, one of the most important global hubs of the ornamental aquarium trade, and discuss associated conservation concerns. We recorded freshwater molluscs from ornamental pet shops and major exporters including non-ornamental species (e.g., hitchhikers, molluscs sold as fish feed). We recorded an unexpectedly high diversity-59 species-of freshwater bivalves and gastropods, with the majority (38 species or 64%) being from the Oriental region. In addition to morphological examination, we sequenced the DNA barcode region of mitochondrial CO1 and 16S genes to provide molecular data for the confirmation of the identification and for future re-identification. DNA barcodes were obtained for 50 species, and all but four were separated by > 3% uncorrected pairwise distances. The trade has been considered a main introduction pathway for non-native species to Singapore, and we found that out of 15 species in the trade as well as in the wild in Singapore, 12 are either introduced or of unknown origin, representing almost half of the known non-native freshwater molluscs in Singapore. Particularly prevalent are non-ornamental species: six hitchhikers on aquarium plants and six species sold as fish feed. We found that a quarter of the trade species have a history of introduction, which includes 11 known or potentially invasive species. We conclude that potential overharvesting is difficult to assess because only half of the trade species have been treated by IUCN. Of these, 21 species are of Least Concern and three are Data Deficient. Our checklist, with accompanying DNA barcodes, images, and museum vouchers, provides an important reference library for future monitoring

  18. Revision of the Late Permian Non-Marine Bivalve Genus Verneuilunio Starobogatov, 1987

    Directory of Open Access Journals (Sweden)

    M.N. Urazaeva

    2015-03-01

    Full Text Available The genus Verneuilunio (type species Naiadites verneuili has been singled out from the genus Palaeanodonta Amalitzky based on differences in the structure of hinge margin established using the literature data. Both genera have been included in the family Palaeanodontidae, which used to be considered by the discoverer of this genus as a subjective synonym for the family Palaeomutelidae. The revision of W. Amalitskii’s collection has demonstrated that the original diagnosis of the genus con-tains a number of inaccuracies. This creates difficulties for identification of the genus Verneuilunio and complicates its placement within higher taxa. The paper presents a revised diagnosis of the genus Verneuilunio. The detailed description of its type species is provided. The genus Verneuilunio has been assigned to the family Naiaditidae based on the duplivincular and slightly amphidetic ligament. According to this feature, the genus under study is significantly different from other unio-like Late Permian non-marine bivalve genera (Palaeomutela, Palaeanodonta, Oligodontella, and Opokiella, often occurring in the same strata. The genus Verneuilunio mostly resembles some Late Carboniferous “atypical” unio-like species of the genus Anthraconaia Trueman et Weir. Statistical processing of the biometric parameters of Verneuilunio verneuili and the species A. pruvosti, mostly resembling it, has revealed statistically significant differences in elongation of the posterior end of the shell. To date, the geographic range of the genus Verneuilunio is restricted to the central part of the East European Platform, whereas its stratigraphic range is in the lower sublayer of the Severodvinsk layer.

  19. Burrowing behavior of a deposit feeding bivalve predicts change in intertidal ecosystem state

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    Tanya Joan Compton

    2016-03-01

    Full Text Available Behavior has a predictive power that is often underutilized as a tool for signaling ecological change. The burrowing behavior of the deposit feeding bivalve Macoma balthica reflects a typical food-safety trade-off. The choice to live close to the sediment surface comes at a risk of predation and is a decision made when predation danger, food intake rates or future fitness prospects are low. In parts of the Dutch Wadden Sea, Macoma populations declined by 90% in the late 1990s, in parallel with large-scale mechanical cockle-dredging activities. During this decline, the burrowing depth of Macoma became shallow and was correlated with the population decline in the following year, indicating that it forecasted population change. Recently, there has been a series of large recruitment events in Macoma. According to the food-safety trade-off, we expected that Macoma should now live deeper, and have a higher body condition in association with this change in depth of living. Indeed, we observed that Macoma now lives deeper and that living depth in a given year forecasted population growth to the next year, especially in individuals larger than 14 mm. As living depth and body condition were strongly correlated in individuals larger than 14 mm, larger Macoma could be living deeper to protect their reproductive assets. Our results confirmed that burrowing depth signals impending population change and, together with body condition, can provide an early warning signal of ecological change. We suggest that population recovery is being driven by improved intertidal habitat quality in the Dutch Wadden Sea, rather than by the proposed climate-change related effects. This shift in ecosystem state is suggested to include the recovery of diatom habitat in the top layer of the sediment after cockle-dredging ended.

  20. Genetic connectivity between north and south Mid-Atlantic Ridge chemosynthetic bivalves and their symbionts.

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    Karina van der Heijden

    Full Text Available Transform faults are geological structures that interrupt the continuity of mid-ocean ridges and can act as dispersal barriers for hydrothermal vent organisms. In the equatorial Atlantic Ocean, it has been hypothesized that long transform faults impede gene flow between the northern and the southern Mid-Atlantic Ridge (MAR and disconnect a northern from a southern biogeographic province. To test if there is a barrier effect in the equatorial Atlantic, we examined phylogenetic relationships of chemosynthetic bivalves and their bacterial symbionts from the recently discovered southern MAR hydrothermal vents at 5°S and 9°S. We examined Bathymodiolus spp. mussels and Abyssogena southwardae clams using the mitochondrial cytochrome c oxidase subunit I (COI gene as a phylogenetic marker for the hosts and the bacterial 16S rRNA gene as a marker for the symbionts. Bathymodiolus spp. from the two southern sites were genetically divergent from the northern MAR species B. azoricus and B. puteoserpentis but all four host lineages form a monophyletic group indicating that they radiated after divergence from their northern Atlantic sister group, the B. boomerang species complex. This suggests dispersal of Bathymodiolus species from north to south across the equatorial belt. 16S rRNA genealogies of chemoautotrophic and methanotrophic symbionts of Bathymodiolus spp. were inconsistent and did not match the host COI genealogy indicating disconnected biogeography patterns. The vesicomyid clam Abyssogena southwardae from 5°S shared an identical COI haplotype with A. southwardae from the Logatchev vent field on the northern MAR and their symbionts shared identical 16S phylotypes, suggesting gene flow across the Equator. Our results indicate genetic connectivity between the northern and southern MAR and suggest that a strict dispersal barrier does not exist.

  1. Eocene Antarctic seasonality inferred from high-resolution stable isotope profiles of fossil bivalves and driftwood

    Science.gov (United States)

    Judd, E. J.; Ivany, L. C.; Miklus, N. M.; Uveges, B. T.; Junium, C. K.

    2017-12-01

    The Eocene Epoch was a time of large-scale global climate change, experiencing both the warmest temperatures of the Cenozoic and the onset of southern hemisphere glaciation. The record of average global temperatures throughout this transition is reasonably well constrained, however considerably less is known about the accompanying changes in seasonality. Seasonally resolved temperature data provide a wealth of information not readily available from mean annual temperature data alone. These data are particularly important in the climatically sensitive high latitudes, as they can elucidate the means by which climate changes and the conditions necessary for the growth of ice sheets. Several recent studies, however, have suggested the potential for monsoonal precipitation regimes in the early-middle Eocene high latitudes, which complicates interpretation of seasonally resolved oxygen isotope records in shallow nearshore marine settings. Seasonal precipitation and runoff could create a brackish, isotopically depleted lens in these environments, depleting summertime δ18Ocarb and thereby inflating the inferred mean and range of isotope-derived temperatures. Here, we assess intra-annual variations in temperature in shallow nearshore Antarctic waters during the middle and late Eocene, inferred from high-resolution oxygen isotope profiles from accretionary bivalves of the La Meseta Formation, Seymour Island, Antarctica. To address concerns related to precipitation and runoff, we also subsample exceptionally preserved fossil driftwood from within the formation and use seasonal differences in δ13Corg values to estimate the ratio of summertime to wintertime precipitation. Late Eocene oxygen isotope profiles exhibit strongly attenuated seasonal amplitudes and more enriched mean annual values in comparison with data from the middle Eocene. Preliminary fossil wood data are not indicative of a strongly seasonal precipitation regime, implying that intra-annual variation in oxygen

  2. Histopathologic and biochemical responses in Arctic marine bivalve molluscs exposed to experimentally spilled oil

    Energy Technology Data Exchange (ETDEWEB)

    Neff, J.M.; Hillman, R.E.; Carr, R.S.; Buhl, R.L.; Lahey, J.I.

    1987-01-01

    Following two experimental spills of chemically dispersed and undispersed crude oil in shallow bays on the northwest coast of Baffin Island bivalve molluscs accumulated significant amounts of petroleum hydrocarbons in bay receiving dispersed oil and in those receiving crude oil alone. Specimens of Mya truncata and Macoma calcarea for histopathologic examination were collected immediately before, immediately after and one year after the experimental oil spills. Immediately after there was increased gill and digestive tract necrosis in Mya from the chemically dispersed oil. After one year a few clams had granulocytomas throughout the tissues. Three clams receiving oil alone collected one year after the spill had invasive neoplasias. There were few lesions in Macoma immediatelly after or one year after the spill; animals had a high incidence of vacuolization of the digestive tubule epithelium. The incidence of parasitism and hemocytic infiltration also was higher in Maccoma. Clams Mya truncata were collected for biochemical analysis before, after and two weeks after the simulated oil spills. Concentations in the clam tissues of glucose, glycogen, trehalose, total lipid, and free amino acids were measured; free amino acids in adductor muscles were the most useful indices of pollutant stress. The results of the biochemical analyses indicate that Mya were not severely stressed by either dispersed oil or oil alone. After two weeks, clams from the dispersed oil bays were nearly normal, while those from the bay receiving oil alone appeared stressed. These results seem to corroborate results that the acute effects of dispersed oil are greater than those of undispersed oil, but effects of undispersed oil on infaunal molluscs develop more slowly and persist longer than those from dispersed oil. 43 refs., 2 figs., 6 tabs.

  3. Biological Carbon Dioxide Assimilation Process Using Marine Phytoplankton Tetraselmis suecica and Bivalve Perna viridis

    Directory of Open Access Journals (Sweden)

    Sirichai Dharmvanij

    2012-01-01

    Full Text Available The Biological CO2 assimilation process using marine phytoplankton and marine bivalve was evaluated by carbon assimilation of the green mussel Perna viridis fed with Tetraselmis suecica under laboratory condition. Incorporation of carbon dioxide into phytoplankton biomass was performed through aeration. The experiment consisted of three treatments i.e. mussels without feeding (Control, mussels fed with T. suecica cultured with air (Treatment 1: T-Air, and mussels fed with T. suecica cultured with 1.5% CO2 in air (Treatment 2: T-CO2. The results showed that growth of mussels in T-Air and T-CO2 was 22.4 ± 4.0 mg/individual/day and 28.9 ± 12.3 mg/individual/day, respectively, which was significantly higher than control (mussels without feeding. Growth of mussels in T-Air was significantly lower than in T-CO2. Carbon content in shell (15.59 ± 0.57 % D.W. and meat (38.28 ± 1.72 % D.W. of mussels fed with aerated T. suecica (T-Air was significantly higher than that found in mussels fed with 1.5% CO2 T. suecica (14.2 ± 0.47 and 36.61± 0.43 % D.W. in shell and in meat, respectively (p≤0.05. With T-Air, 1.95±0.27 and 9.36±1.24% of carbon from T. suecica cells was assimilated into shell and meat of the mussel, respectively, while in T-CO2 , carbon assimilation from T. suecica cells in shell and meat was 2.19±0.55 and 11.22±2.76% respectively.

  4. Effect of chronic selenium exposure on the freshwater bivalve Corbicula fluminea

    Energy Technology Data Exchange (ETDEWEB)

    Fournier, E.; Adam, C.; Massabuau, J.C.; Garnier-Laplace, J. [CEA Cadarache (DEI/SECRE/LRE), Laboratory of Radioecology and Ecotoxicology, Institute for Radioprotection and Nuclear Safety, 13 - Saint-Paul-lez-Durance (France)

    2004-07-01

    Selenium is essential for most of living organisms. In oxic to moderately oxic fresh-waters, Se exists predominantly in the (+VI) and (+IV) oxidation states as selenate (SeO{sub 4}{sup 2-}) and selenite (SeO{sub 3}{sup 2-}) respectively, whereas in the biota it is incorporated as Se(-II) into seleno-proteins or amino-acids, or as elemental selenium Se(0). At low concentrations, it acts against oxidative damages mainly as the glutathione peroxidase seleno-dependant, but it may be toxic at higher levels (for example, by replacing sulphur in important biomolecules). In filter feeders, such as the freshwater bivalve Corbicula fluminea, selected as biological model, the ventilation activity is a primary limiting step that controls the water influx and therefore the delivery of contaminants. Consequently, a series of short-term experiments were performed to study the effects of different dissolved Se concentrations and forms (selenite; selenate; selenomethionine) on the ventilation activity of Corbicula fluminea and Se tissular distribution. The modification of the ventilation activity of the Se-exposed groups, in comparison to this of reference groups (not exposed to Se) varied greatly according to the form and the concentrations of the Se used. Se concentrations in tissues indicated that selenite was the less bioavailable form whereas selenomethionine displayed the opposite trend. On the basis of this set of experiments, a limited number of conditions have been selected to provide highly contrasting ventilation flow rates and selenium bioaccumulation levels, in order to study the effects of long term exposures, i) at the molecular level, by measuring bio-markers of oxidative stress (forms of glutathione, glutathione peroxidase, glutathione reductase, superoxide dismutase, catalase, and bio-marker of genotoxicity (comet assay), ii) at the (sub)cellular level by analysing Se micro-localisation in target organs and iii) at the individual level by monitoring the variation

  5. Habitat creation and biodiversity maintenance in mangrove forests: teredinid bivalves as ecosystem engineers

    Directory of Open Access Journals (Sweden)

    Ian W. Hendy

    2014-09-01

    Full Text Available Substantial amounts of dead wood in the intertidal zone of mature mangrove forests are tunnelled by teredinid bivalves. When the tunnels are exposed, animals are able to use tunnels as refuges. In this study, the effect of teredinid tunnelling upon mangrove forest faunal diversity was investigated. Mangrove forests exposed to long emersion times had fewer teredinid tunnels in wood and wood not containing teredinid tunnels had very few species and abundance of animals. However, with a greater cross-sectional percentage surface area of teredinid tunnels, the numbers of species and abundance of animals was significantly higher. Temperatures within teredinid-attacked wood were significantly cooler compared with air temperatures, and animal abundance was greater in wood with cooler temperatures. Animals inside the tunnels within the wood may avoid desiccation by escaping the higher temperatures. Animals co-existing in teredinid tunnelled wood ranged from animals found in terrestrial ecosystems including centipedes, crickets and spiders, and animals found in subtidal marine ecosystems such as fish, octopods and polychaetes. There was also evidence of breeding within teredinid-attacked wood, as many juvenile individuals were found, and they may also benefit from the cooler wood temperatures. Teredinid tunnelled wood is a key low-tide refuge for cryptic animals, which would otherwise be exposed to fishes and birds, and higher external temperatures. This study provides evidence that teredinids are ecosystem engineers and also provides an example of a mechanism whereby mangrove forests support intertidal biodiversity and nurseries through the wood-boring activity of teredinids.

  6. Arteritis de células gigantes (Arteritis temporal Utilidad del Eco-Doppler Color en el diagnóstico

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    Hugo Tarigo

    2016-09-01

    El objetivo de la presente comunicación es reafirmar la utilidad y valor de este método diagnóstico, subutilizado en nuestra práctica clínica, en pacientes con planteo de arteritis de células gigantes.

  7. Respiration of bivalves from three different deep-sea areas: Cold seeps, hydrothermal vents and organic carbon-rich sediments

    Science.gov (United States)

    Khripounoff, A.; Caprais, J. C.; Decker, C.; Le Bruchec, J.; Noel, P.; Husson, B.

    2017-08-01

    We studied bivalves (vesicomyids and mytilids) inhabiting four different areas of high sulfide and methane production: (1) in the Gulf of Guinea, two pockmarks (650 m and 3150 m depth) and one site rich in organic sediments in the deepest zone (4950 m average depth), (2) at the Azores Triple Junction on the Mid-Atlantic Ridge, one hydrothermal site (Lucky Strike vent field, 1700 m depth). Two types of Calmar benthic chambers were deployed, either directly set into the sediment (standard Calmar chamber) or fitted with a tank to isolate organisms from the sediment (modified Calmar chamber), to assess gas and solute exchanges in relation to bivalve bed metabolism. Fluxes of oxygen, total carbon dioxide, ammonium and methane were measured. At the site with organic-rich sediments, oxygen consumption by clams measured in situ with the standard benthic chamber was variable (1.3-6.7 mmol m-2 h-1) as was total carbon dioxide production (1-9.6 mmol m-2 h-1). The observed gas and solute fluxes were attributed primarily to bivalve respiration (vesicomyids or mytilids), but microbial and geochemical processes in the sediment may be also responsible for some of variations in the deepest stations. The respiration rate of isolated vesicomyids (16.1-0.25.7 μmol g-1 dry weight h-1) was always lower than that of mytilids (33 μmol g-1 dry weight h-1). This difference was attributed to the presence of a commensal scaleworm in the mytilids. The respiratory coefficient (QR) ≥1 indicated high levels of anaerobic metabolism. The O:N index ranged from 5 to 25, confirming that vesicomyids and mytilids, living in symbiosis with bacteria, have a protein-based food diet.

  8. Immunomodulation by different types of N-oxides in the hemocytes of the marine bivalve Mytilus galloprovincialis.

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    Caterina Ciacci

    Full Text Available The potential toxicity of engineered nanoparticles (NPs for humans and the environment represents an emerging issue. Since the aquatic environment represents the ultimate sink for NP deposition, the development of suitable assays is needed to evaluate the potential impact of NPs on aquatic biota. The immune system is a sensitive target for NPs, and conservation of innate immunity represents an useful basis for studying common biological responses to NPs. Suspension-feeding invertebrates, such as bivalves, are particularly at risk to NP exposure, since they have extremely developed systems for uptake of nano and microscale particles integral to intracellular digestion and cellular immunity. Evaluation of the effects of NPs on functional parameters of bivalve immunocytes, the hemocytes, may help understanding the major toxic mechanisms and modes of actions that could be relevant for different NP types in aquatic organisms.In this work, a battery of assays was applied to the hemocytes of the marine bivalve Mytilus galloprovincialis to compare the in vitro effects of different n-oxides (n-TiO(2, n-SiO(2, n-ZnO, n-CeO(2 chosen on the basis of their commercial and environmental relevance. Physico-chemical characterization of both primary particles and NP suspensions in artificial sea water-ASW was performed. Hemocyte lysosomal and mitochondrial parameters, oxyradical and nitric oxide production, phagocytic activity, as well as NP uptake, were evaluated. The results show that different n-oxides rapidly elicited differential responses hemocytes in relation to their chemical properties, concentration, behavior in sea water, and interactions with subcellular compartments. These represent the most extensive data so far available on the effects of NPs in the cells of aquatic organisms. The results indicate that Mytilus hemocytes can be utilized as a suitable model for screening the potential effects of NPs in the cells of aquatic invertebrates, and may

  9. Study on the bioaccumulation of Polonium-210 on bivalve indicator organisms of Tamilnadu and Pondicherry coast (East Coast of India)

    International Nuclear Information System (INIS)

    Syed Mohamed, H.E.; Sadiq Bukhari, A.; Meeramaideen, M.; Masilamani, V.; Shamsudin, Mohamed; Shahul Hameed, P.

    2012-01-01

    210 Po is a major contributor (90%) of the natural radiation dose from alpha-emitting radionuclides, received by most marine organisms. Among marine organisms, benthic fauna are superior to many other biological groups, since they could be monitored due to their sedentary habits and then must either adapt to environmental stress or perish. They also reflect the water conditions not only at the time of sampling but also for some past time as well. The affinity of 210 Po for protein enables it to pass through the food chain, and increased body burdens of 210 Po have been found where diets include protein-rich meat and seafood. The present study was launched to evaluate the rate of accumulation of 210 Po in the benthic bivalve molluscs such as Perna indica, P.viridis, Meretrix casta, Cardium coronatum, Gafrarium tumidum, Paphia textrix, Vellorita cyprinodea and Pinctada sp., of Tamilnadu and Pondicherry coast. Water samples, sediments and bivalves were collected from Gulf of Mannar (6 sampling stations), Palk Strait (8 sampling stations) of Tamilnadu and Pondicherry (6 sampling stations). 210 Po determination as made was as per standard protocols. The results showed that 210 Po concentration in coastal waters of Gulf of Mannar, Palk Strait and Pondicherry ranged 0.5 - 2.83 mBq/l (mean 1.33 mBq/I), 2.14 - 32.14 mBq/l (mean 15.3 mBq/l) and 1.36 - 2.0 mBq/1 (mean 1.59 mBq/1) respectively. The sediments maintained higher level of 210 Po (mean value of 3.62 Bq/kg in Gulf of Mannar, 107.9 Bq/kg in Palk Strait and 3.0 Bq/kg in Pondicherry) than water. The 210 Po rich sediment therefore serves as a vital link in the transfer of Polonium from water to the marine organisms. The concentration of 210 Po in eight species of bivalves collected from the study area, recorded a maximum level ranging from 65.2 to 2668.9 Bq/kg in soft tissues and from 1.19 to 15.3 Bq/kg in shells. The bioaccumulation ability in bivalve species with reference to 210 Po was observed to be highly variable

  10. Bioacessibilidade in vitro das biotoxinas marinhas ácido ocadaico, dinofisistoxina-2 e seus derivados em bivalves crus e cozinhados

    OpenAIRE

    Manita, Diana Filipa Pereira

    2017-01-01

    Dissertação de Mestrado em Segurança Alimentar As biotoxinas marinhas mais frequentes e abundantes em Portugal são as toxinas lipofílicas, nomeadamente as toxinas do grupo do ácido ocadaico (AO), que inclui as dinofisistoxinas (DTX1 e DTX2) e os seus derivados (DTX3), responsáveis pela intoxicação diarreica (DSP diarrhetic shellfish poisoning). A investigação da presença, variabilidade e transformação de biotoxinas marinhas em moluscos bivalves é de elevada importância não só p...

  11. Plio-Pleistocene extinctions and immigration credit reflected in the size-frequency distribution of Mediterranean marine bivalves

    Science.gov (United States)

    Nawrot, Rafal; Zuschin, Martin; Chattopadhyay, Devapriya

    2015-04-01

    Following the opening of the Suez Canal hundreds of Red Sea species have entered the Mediterranean Sea making it a global hot spot of marine bioinvasion. With the ongoing influx of the subtropical and tropical alien species and increasing sea surface temperatures, the Mediterranean biota is currently gaining a more tropical character and increasingly becoming a mixture of faunal stocks with different evolutionary histories. This susceptibility to invasion was suggested to reflect the presence of an empty ecological space left after decimation of incumbent warm-water fauna during Plio-Pleistocene climate fluctuations. As molluscs are among the most prolific immigrants, we test this hypothesis using data on taxonomic composition and body size of Pliocene Mediterranean bivalves derived from the literature sources and museum collections. The Pliocene inter-specific size-frequency distribution (SFD) is strikingly similar to the SFDs of the Recent Red Sea bivalve fauna, in spite of different biogeographic provenance and the absence of true reef ecosystems in the Pliocene of the Mediterranean region. In contrast, body-size patterns in both assemblages are significantly different from the present-day Mediterranean fauna characterized by smaller median and modal size. Our preliminary results suggest that the distinct shape of the modern Mediterranean SFD may reflect the selective nature of the late Piacenzian - Galesian (Late Pliocene - Early Pleistocene) extinctions pulses related to the onset of the Northern Hemisphere glaciations. These extinctions affected almost 40% of Pliocene species and were biased towards large-bodied taxa. They were not followed by re-immigration of warm-water species owing to the isolation from the tropical Atlantic biota by the cold upwelling along the NW coasts of Africa. The resulting invasion credit (sensu Jackson & Sax, 2010) is currently being paid by the Red Sea bivalves colonizing the Mediterranean Sea through the Suez Canal. Successful

  12. Chemosymbiotic bivalves from the mud volcanoes of the Gulf of Cadiz, NE Atlantic, with descriptions of new species of Solemyidae, Lucinidae and Vesicomyidae.

    Science.gov (United States)

    Olive, Graham; Rodrigues, Clara F; Cunha, Marina R

    2011-01-01

    The chemosymbiotic bivalves collected from the mud volcanoes of the Gulf of Cadiz are reviewed. Of the thirteen species closely associated with chemosynthetic settings two Solemyidae, Solemya (Petrasma) elarraichensissp. n. and Acharax gadiraesp. n., one Lucinidae, Lucinoma asapheussp. n., and one Vesicomyidae, Isorropodon megadesmussp. n. are described and compared to close relatives of their respective families. The biodiversity and distribution of the chemosymbiotic bivalves in the Gulf of Cadiz are discussed and compared to the available information from other cold seeps in the Eastern Atlantic and Mediterranean. Although there is considerable similarity at the genus level between seep/mud volcano fields in the Eastern Atlantic and Mediterranean, there is little overlap at the species level. This indicates a high degree of endemism within chemosymbiotic bivalve assemblages.

  13. Abundance, biomass and caloric content of Chukchi Sea bivalves and association with Pacific walrus (Odobenus rosmarus divergens) relative density and distribution in the northeastern Chukchi Sea

    Science.gov (United States)

    Young, Jordann K.; Black, Bryan A.; Clarke, Janet T.; Schonberg, Susan V.; Dunton, Kenneth H.

    2017-10-01

    The northeastern Chukchi Sea is a shallow subarctic shelf ecosystem that supports a substantial benthic infaunal community of which bivalves are a major component. We assessed the patterns in population abundance, biomass, and caloric content of ten dominant bivalve taxa in relation to the distribution of the upper trophic level consumer Pacific walrus (Odobenus rosmarus divergens). Bivalves were collected over four cruises in the northeastern Chukchi Sea (2009, 2010, 2012, 2013). Our samples were largely dominated by calorie-dense, deposit-feeding species, including Macoma spp., Ennucula tenuis, Nuculana spp. and Yoldia spp. Weight-frequency distributions were strongly right-skewed for most taxa, though some showed evidence of a bimodal distribution. Caloric densities as measured through bomb calorimetry significantly differed among taxa (ANOVA F = 32.57, df = 9, p-valueanimal wet weight was found to be a reliable predictor of whole animal caloric content. Bivalve populations and peak caloric densities were centered on and to the southeast of Hanna Shoal, which coincided with peak Pacific walrus relative density (walruses per km surveyed) from July through October. Significant differences in mean caloric values were found between areas with and without walruses present (student's t-test, t=-2.9088, df = 252.24, p-value = 0.003952), as well as between areas with low and high walrus relative densities in the pooled annual dataset and in each individual month except October (ANOVA, p-value<0.05). The high-calorie deposit feeders that dominate these bivalve communities preferentially consume food sources, such as sea ice algae, that are likely to be affected by shifting sea ice dynamics. As such, continued warming has the potential to alter bivalve communities in the northeastern Chukchi Sea, which may have profound implications for upper trophic levels.

  14. Alkylphenols and polycyclic aromatic hydrocarbons in bivalves from Comunidad Valenciana coastal waters; Alquilfenoles e hidrocarburos aromaticos policiclicos en bivalvos de las coastas de la comunidad Valenciana

    Energy Technology Data Exchange (ETDEWEB)

    Marti Ortega, N.; Aguado Garcia, D.; Bouzas Blanco, A.; Segovia Martinez, L.; Albargues Llamas, M.; Sevillano Cabeza, A.; Campins Falco, P.; Seco Torrecillas, A.; Ferrer Polo, J.

    2009-07-01

    This paper reports the results on alkylphenol and polycyclic aromatic hydrocarbons (PAH) pollution in mussels and cleans from Comunidad Valenciana coastal waters, in 2008. The significant presence of nonylphenol observed in both bivalves reflects an exposure to alkyl phenolic surfactants from the discharges of wastewater treatment plants that treat industrial and urban wastewaters, where the presence of alkylphenol polyethoxylated is common due to its extensive use (detergents, solubilizers...). The presence of low levels of PAH was observed in most of the studied areas. However, it must be highlighted that bivalves consumption does not imply any risk for human health. (Author) 21 refs.

  15. The quagga mussel (Dreissena rostriformis bugensis Andrusov, 1897) – another Ponto-Caspian dreissenid bivalve in the southern Baltic catchment: the first record from the Szczecin Lagoon

    OpenAIRE

    Adam Woźniczka; Brygida Wawrzyniak-Wydrowska; Teresa Radziejewska; Anna Skrzypacz

    2016-01-01

    In 2014, a non-indigenous dreissenid bivalve, the quagga mussel (Dreissena rostriformis bugensis Andrusov, 1897) was for the first time recorded in the Szczecin Lagoon. This was also the first record of the species in the Baltic Sea catchment. The quagga mussel was found to accompany the zebra mussel (Dreissena polymorpha), a non-indigenous bivalve already firmly established in the Lagoon. As indicated by the new immigrant's estimated abundance (4000.0 ± 355.44 ind. m−2) and the zebra mussel ...

  16. The role of the seed coat in the light sensivity in Raphanus sativus L. cv. redondo gigante seeds O papel do tegumento na sensibilidade à luz em sementes de Raphanus sativus L. cv. redondo gigante

    Directory of Open Access Journals (Sweden)

    Maura Lúcia Costa Gonçalves

    1997-07-01

    Full Text Available The role of the seed coat in the light sensitivity of seeds of Raphanus sativus L. cv. redondo gigante was analysed by germination tests of intact and naked seeds. Far-red light caused high inhibition of seed germination, while under white and red lights low inhibition was found. Naked seeds presented no light sensitivity with high percentage germination under light and darkness. However, incubation of naked seeds in -0.6MPa polyethylene glycol solution resulted in light inhibition as observed in intact seeds. The analysis of the seed coat transmitted light indicated that the filtered light presented the same photoequilibrium of phytochrome when compared to the white light, with a decrease of only 33% in the light irradiance which reaches the embryo.O papel do tegumento sobre a sensibilidade à luz em sementes de Raphanus sativus L. cv. redondo gigante foi analisado por testes de germinação de sementes intactas e nuas. A luz vermelho-extremo inibiu fortemente a germinação, enquanto as luzes branca e vermelha apresentaram baixa inibição. Por outro lado, sementes nuas não apresentaram sensibilidade à luz, com alta porcentagem de germinação tanto na luz como no escuro. Entretanto, a incubação das sementes nuas em condições de estresse em solução de polietilenoglicol a -0,6MPa, resultou em inibição na luz, como observadas em sementes intactas. A análise da luz transmitida pelo tegumento das sementes indicou que a luz filtrada apresenta o mesmo fotoequilíbrio teórico do fitocromo obtido na luz branca, com um decréscimo em apenas 33% da irradiância que atinge o embrião.

  17. Gigantes da internet e práticas fiscais desleais / Internet Giants and Unfair Tax Practices

    Directory of Open Access Journals (Sweden)

    Ludovic Ayrault

    2018-05-01

    analisa o problema com base na legislação tributária francesa, em contraste com fontes internacionais da OCDE – Organização para Cooperação e Desenvolvimento Econômico – e de outros países, como Estados Unidos da América e Irlanda. Além da apreciação jurídica, são analisados relatórios e casos. Resultados – No que se refere às falhas de legislação, mostra-se a “relação territorial” e o “preço de transferência” como os principais elementos para o debate sobre a elisão fiscal. Em relação às formas de enfrentamento de práticas desleais, encontram-se a luta contra jurisdições fiscais complacentes bem como a exigência de transparência sobre as empresas, com obrigações de informação. Implicações práticas – Permite-se esclarecer, assim, o comportamento fiscal adotado pelas empresas gigantes da Internet, bem como as possíveis formas de enfrentamento dessas práticas desleais, com base no contexto europeu. Originalidade – A originalidade se dá justamente em problematizar o comportamento fiscal de grandes corporações da Internet e elucidar os meios possíveis para tentar coibir as práticas desleais.

  18. Distribution and density of the bivalve Anomalocardia brasiliana in the estuarine region of Northeastern Brazil

    Directory of Open Access Journals (Sweden)

    A. M. L. Rodrigues Maia

    2017-06-01

    Full Text Available Abstract The objective of this study was to analyze the density and distribution of the bivalve Anomalocardia brasiliana in beaches in the estuarine region of the semiarid in Rio Grande do Norte State, Barra and Pernambuquinho (04°56.978’S and 37°08.961’W and 04°56.792’S and 37°09.375’W, respectively. Samples were collected monthly during 37 months using five transects (300 m long and 400 m apart laid perpendicularly to the beach line toward the sea. Seven collection points, 50 m apart, were set in each transect, and shellfish and sediment samples were collected. Temperature and salinity were measured in each transect. The results showed a temperature variation of average values of 3 °C; the greatest variation (33.2 °C was observed in May of 2009. The lowest average salinity values were observed between April and June of 2009 (5, 8.7, and 7.8, respectively. This fact was due to an atypical rainfall in the region, which resulted in a large freshwater inflow into the estuary; the average salinity values were about 40 in the remaining months. The highest precipitation values were observed in April/09, April/10, and April/11; the highest precipitation occurred in April/09 (316.3 mm. The lower average densities of A. brasiliana were observed in April and May/09 when compared to the other months; the lowest value was observed in April/09 (26 ind/m2. The highest densities occurred between November/10 and July/11, with values ranging from 70 to 322 ind/m2. The highest inflow of young individuals (lengths from 2 to 5 mm was observed between April and June of 2010 and on September/10 while the highest frequency of adults (from 20 to 25 mm occurred between December of 2010 and April of 2011. Hence, the results of this study show that in the months with the greatest rainfall, salinity and the average density of A. brasiliana showed the lowest values.

  19. Effect of the exposure to suspended solids on the enzymatic activity in the bivalve Sinonovacula constricta

    Directory of Open Access Journals (Sweden)

    Guojun Yang

    2017-01-01

    Full Text Available Aquatic animals are susceptible to sudden changes of their living environment but they adopt strategies to cope with adverse environmental challenges. Contamination by suspended solids, often associated with a dramatic change in the concentrations of important water-quality variables is a frequent occurrence in China's coastal waters and estuaries. Here we studied the impact of suspended solids on the activities of the antioxidant enzymes superoxide dismutase (SOD and catalase (CAT, as well as adenosine triphosphates (including Na+ K+-ATPase, Mg+ +-ATPase, Ca+ +-ATPase and H+ K+-ATPase in the gills and visceral mass tissues of the molluscan bivalve Sinonovacula constricta exposed (4, 8, 12, 16, 20, and 24 days to various concentrations of suspended solids. Our results showed that the antioxidant enzymes cooperated closely to effectively scavenge superoxide anion free radicals and H2O2 (which can ultimately inhibit gill activity through the modification of SOD and/or CAT enzymatic activities. ATPases activity (considered to be a sensitive indicator of toxicity could play an effective role in the maintenance of functional integrity of the plasma membranes as well as some other intracellular functions. After the exposure, a decrease in the Na+ K+-ATPase, Mg+ +-ATPase, and Ca+ +-ATPase activity of the gills was observed suggesting that they were inhibited by the treatments. These results also indicated that, from day 4 to day 16, exposure to high concentrations of suspended solids had an inhibitory effect on the activity of H+-K+-ATPase in the visceral mass of S. constricta. However, after a period of adaptation the H+-K+-ATPase activity was restored to original levels. Our results suggest that long-term exposure to high levels of suspended solids disturb osmoregulation, gastric acid secretion and digestion, cause oxidative damage, as a consequence of antioxidant enzymes inactivation which eventually damages the gills, affect the food intake

  20. Uptake and loss of 134Cs and 60Co by the Baltic bivalve Macoma Baltica under laboratory conditions

    International Nuclear Information System (INIS)

    Evans, S.

    1982-01-01

    In order to predict the radiological impact on man via harvestable sea food products, it is essential to make a critical evaluation of the transfer routes and the rates on which radionuclides are transferred through the aquatic food chains. In the Baltic, the bivalve Macoma Baltica comprises a main food item for fish species of commercial interest, such as flounder. The accumulation and release of Cs-134 and Co-60 by Macoma was experimentally investigated. The nuclides were added to the water and the activity content of the bivalves was determined at regular intervals. The uptake was quite rapid, 40 per cent (Cs) and 55 per cent (Co) respectively of the final steady state was obtained after 24 hours. The subsequent release was rapid as well, 50 per cent (Cs) and 40 per cent (Co) respectively of the accumulated activity was lost within 6 days. The experiments demonstrated that the major intake route following short-term releases of activity will be from the water column. The close connection between activity in water and organism can thus be used for predictive purposes without the complication of radionuclide uptake from contaminated sediments. (Author)

  1. Biomarkers of metabolism disturbance in bivalve molluscs induced by environmental pollution with processed by-products of oil

    Directory of Open Access Journals (Sweden)

    E. V. Sukharenko

    2017-05-01

    Full Text Available Processed by-products of oil are the most common pollutants in all river and sea water. The increase in oxidative stress in bivalve molluscs was studied in both tissues of the hepatopancreas and the gill. The model for artificial treatment with processed by-products of oil was performed in a laboratory experiment with the river mollusc Dreissena polymorpha Pallas, 1771. The exposure of the molluscs over 28 days to mazut 50 mg/l induced significant increase of both final product of lipid peroxidation (LPO and antioxidant enzime activity. A significant increase in LPO was observed in the hepatopancreas and gill of D. polymorpha treated with mazut compared to the control group. Antioxidant enzyme activity of cartalase, supeoxide dismutase, glutathione reductase and glutathione-S-transferase showed a greater increase (by almost 1.5 times in the hepatopancreas than in the gill of D. polymorpha. A similar LPO growth and modulation of antioxidant enzyme activity were determined in the hepatopancreas and gill of the mussel Mytilus galloprovincialis Lamarck, 1879 collected in an area polluted with resins, hydrocarbons and asphaltenes, Donuzlav lake in the Kerch gulf. Varied cellular reactivation of the antioxidant enzyme system in the hepatopancreas rather than the gill was observed in both kinds of mollusc Dreissena and Mytilus. The obtained results are evidence of the higher sensitivity of the hepatopancreas cells of bivalve molluscs to organic pollutants compared to the gill cells.

  2. Liderazgo, la competencia esencial que transformó una empresa colombiana en un gigante internacional : el caso de Cementos Argos

    Directory of Open Access Journals (Sweden)

    Héctor Ochoa Díaz, Ph.D.

    2011-09-01

    Full Text Available Cementos Argos ha sido catalogado como uno de los gigantes de la industria cementera colombiana por su gran capacidad de consolidación en el mercado nacional y sus estrategias de internacionalización poco convencionales. Esta investigación documenta la experiencia internacional de Argos bajo la perspectiva de las teorías de internacionalización de mayor aceptación en la literatura internacional, haciendo uso del enfoque metodológico de los estudios de caso. Como resultado se encontró que las estrategias de fidelización, aunadas al rediseño organizacional resultado del liderazgo de la alta gerencia, han sido herramientas vitales para asegurar el crecimiento de la compañía en los mercados local y externo.

  3. LIDERAZGO, LA COMPETENCIA ESENCIAL QUE TRANSFORMÓ UNA EMPRESA COLOMBIANA EN UN GIGANTE INTERNACIONAL: EL CASO DE CEMENTOS ARGOS

    Directory of Open Access Journals (Sweden)

    HÉCTOR OCHOA DÍAZ

    2011-01-01

    Full Text Available Cementos Argos ha sido catalogado como uno de los gigantes de la industria cementera colombiana por su gran capacidad de consolidación en el mercado nacional y sus estrategias de internacionalización poco convencionales. Esta investigación documenta la experiencia internacional de Argos bajo la perspectiva de las teorías de internacionalización de mayor aceptación en laliteratura internacional, haciendo uso del enfoque metodológico de los estudios de caso. Como resultado se encontró que las estrategias de fidelización,aunadas al rediseño organizacional resultado del liderazgo de la alta gerencia, han sido herramientas vitales para asegurar el crecimiento de la compañía en los mercados local y externo.

  4. Gigantic transverse x-ray magnetic circular dichroism in ultrathin Co in Au/Co/Au(001)

    International Nuclear Information System (INIS)

    Koide, T; Mamiya, K; Asakura, D; Osatune, Y; Fujimori, A; Suzuki, Y; Katayama, T; Yuasa, S

    2014-01-01

    Transverse-geometry x-ray magnetic circular dichroism (TXMCD) measurements on Au/Co-staircase/Au(001) reveal the orbital origin of intrinsic in-plane magnetic anisotropy A gigantic TXMCD was successfully observed at the Co L 3,2 edges for Co thickness (t C0 ) in the 2-monolayer regime. A TXMCD-sum-rule analysis shows a remarkable enhancement of an orbital-moment anisotropy (Δm orb ) and of an in-plane magnetic dipole moment (m || T ). Both Δm orb and m || T exhibit close similarity in t Co dependence, reflecting the in-plane magnetic anisotropy These observations evidence that extremely strong, intrinsic, in-plane magnetic anisotropy originates from the anisotropic orbital part of the wave function, dominating the dipole-dipole-interaction-derived, extrinsic, in-plane magnetic anisotropy.

  5. Gigantic transverse x-ray magnetic circular dichroism in ultrathin Co in Au/Co/Au(001)

    Science.gov (United States)

    Koide, T.; Mamiya, K.; Asakura, D.; Osatune, Y.; Fujimori, A.; Suzuki, Y.; Katayama, T.; Yuasa, S.

    2014-04-01

    Transverse-geometry x-ray magnetic circular dichroism (TXMCD) measurements on Au/Co-staircase/Au(001) reveal the orbital origin of intrinsic in-plane magnetic anisotropy A gigantic TXMCD was successfully observed at the Co L3,2 edges for Co thickness (tC0) in the 2-monolayer regime. A TXMCD-sum-rule analysis shows a remarkable enhancement of an orbital-moment anisotropy (Δmorb) and of an in-plane magnetic dipole moment (m||T). Both Δmorb and m||T exhibit close similarity in tCo dependence, reflecting the in-plane magnetic anisotropy These observations evidence that extremely strong, intrinsic, in-plane magnetic anisotropy originates from the anisotropic orbital part of the wave function, dominating the dipole-dipole-interaction-derived, extrinsic, in-plane magnetic anisotropy.

  6. Gigantic terahertz magnetochromism via electromagnons in the hexaferrite magnet Ba2Mg2Fe12O22

    Science.gov (United States)

    Kida, N.; Kumakura, S.; Ishiwata, S.; Taguchi, Y.; Tokura, Y.

    2011-02-01

    Effects of temperature (6-225 K) and magnetic field (0-7 T) on the low-energy (1.2-5 meV) electrodynamics of the electromagnon, the magnetic resonance driven by the light electric field, have been investigated for a hexaferrite magnet Ba2Mg2Fe12O22 by using terahertz time-domain spectroscopy. We find the gigantic terahertz magnetochromism via electromagnons; the magnetochromic change, as defined by the difference of the absorption intensity with and without magnetic field, exceeds 500% even at 0.6 T. The results arise from the fact that the spectral intensity of the electromagnon critically depends on the magnetic structure. With changing the conical spin structures in terms of the conical angle θ from the proper screw (θ=0°) to the ferrimagnetic (θ=90°) through the conical spin-ordered phases (0°origin of this electromagnon is argued in terms of the exchange-striction mechanism.

  7. Growth rates and geochemical proxies in Late Campanian bivalves - New insights from micro-X-ray Fluorescence mapping and numerical growth modelling

    Science.gov (United States)

    de Winter, Niels; Goderis, Steven; van Malderen, Stijn; Vanhaecke, Frank; Claeys, Philippe

    2017-04-01

    Understanding the Late Cretaceous greenhouse climate is of vital importance for understanding present and future climate change. While a lot of good work has been done to reconstruct climate in this interesting period, most paleoclimatic studies have focused on long-term climate change[1]. Alternatively, multi-proxy records from marine bivalves provide us with a unique opportunity to study past climate on a seasonal scale. However, previous fossil bivalve studies have reported ambiguous results with regard to the interpretation of trace element and stable isotope proxies in marine bivalve shells[2]. One major problem in the interpretation of such records is the bivalve's vital effect and the occurrence of disequilibrium fractionation during bivalve growth. Both these problems are linked to the annual growth cycle of marine bivalves, which introduces internal effects on the incorporation of isotopes and trace elements into the shell[3]. Understanding this growth cycle in extinct bivalves is therefore of great importance for the interpretation of seasonal proxy records in their shells. In this study, three different species of extinct Late Campanian bivalves (two rudist species and one oyster species) that were found in the same stratigraphic interval are studied. Micro-X-Ray Fluorescence line scanning and mapping of trace elements such as Mg, Sr, S and Zn, calibrated by LA-ICP-MS measurements, is combined with microdrilled stable carbon and oxygen isotope analysis on the well-preserved part of the shells. Data of this multi-proxy study is compared with results from a numerical growth model written in the open-source statistics package R[4] and based on annual growth increments observed in the shells and shell thickness. This growth model is used together with proxy data to reconstruct rates of trace element incorporation into the shell and to calculate the mass balance of stable oxygen and carbon isotopes. In order to achieve this goal, 2D mapping of bivalve shell

  8. On the shoulders of giants: Harvey Cushing's experience with acromegaly and gigantism at the Johns Hopkins Hospital, 1896-1912.

    Science.gov (United States)

    Pendleton, Courtney; Adams, Hadie; Salvatori, Roberto; Wand, Gary; Quiñones-Hinojosa, Alfredo

    2011-03-01

    A review of Dr. Cushing's surgical cases at Johns Hopkins Hospital revealed new information about his early operative experience with acromegaly. Although in 1912 Cushing published selective case studies regarding this work, a review of all his operations for acromegaly during his early years has never been reported. We uncovered 37 patients who Cushing treated with surgical intervention directed at the pituitary gland. Of these, nine patients who presented with symptoms of acromegaly, and one with symptoms of gigantism were selected for further review. Two patients underwent transfrontal 'omega incision' approaches, and the remaining eight underwent transsphenoidal approaches. Of the 10 patients, 6 were male. The mean age was 38.0 years. The mean hospital stay was 39.4 days. There was one inpatient death during primary interventions (10%) and three patients were deceased at the time of last follow-up (33%). The mean time to death, calculated from the date of the primary surgical intervention, and including inpatient and outpatient deaths, was 11.3 months. The mean time to last follow-up, calculated from the day of discharge, was 59.3 months. At the time of last follow-up, two patients reported resolution of headache; four patients reported continued visual deficits, and two patients reported ongoing changes in mental status. This review analyzes the outcomes for 10 patients who underwent surgical intervention for acromegaly or gigantism, and offers an explanation for Cushing's transition from the transfrontal "omega incision" to the transsphenoidal approach while practicing at the Johns Hopkins Hospital.

  9. Aggressive tumor growth and clinical evolution in a patient with X-linked acro-gigantism syndrome.

    Science.gov (United States)

    Naves, Luciana A; Daly, Adrian F; Dias, Luiz Augusto; Yuan, Bo; Zakir, Juliano Coelho Oliveira; Barra, Gustavo Barcellos; Palmeira, Leonor; Villa, Chiara; Trivellin, Giampaolo; Júnior, Armindo Jreige; Neto, Florêncio Figueiredo Cavalcante; Liu, Pengfei; Pellegata, Natalia S; Stratakis, Constantine A; Lupski, James R; Beckers, Albert

    2016-02-01

    X-linked acro-gigantism (X-LAG) syndrome is a newly described disease caused by microduplications on chromosome Xq26.3 leading to copy number gain of GPR101. We describe the clinical progress of a sporadic male X-LAG syndrome patient with an Xq26.3 microduplication, highlighting the aggressive natural history of pituitary tumor growth in the absence of treatment. The patient first presented elsewhere aged 5 years 8 months with a history of excessive growth for >2 years. His height was 163 cm, his weight was 36 kg, and he had markedly elevated GH and IGF-1. MRI showed a non-invasive sellar mass measuring 32.5 × 23.9 × 29.1 mm. Treatment was declined and the family was lost to follow-up. At the age of 10 years and 7 months, he presented again with headaches, seizures, and visual disturbance. His height had increased to 197 cm. MRI showed an invasive mass measuring 56.2 × 58.1 × 45.0 mm, with compression of optic chiasma, bilateral cavernous sinus invasion, and hydrocephalus. His thyrotrope, corticotrope, and gonadotrope axes were deficient. Surgery, somatostatin analogs, and cabergoline did not control vertical growth and pegvisomant was added, although vertical growth continues (currently 207 cm at 11 years 7 months of age). X-LAG syndrome is a new genomic disorder in which early-onset pituitary tumorigenesis can lead to marked overgrowth and gigantism. This case illustrates the aggressive nature of tumor evolution and the challenging clinical management in X-LAG syndrome.

  10. Biomonitoring of Heavy metals using the bivalve molluscs in sunderban mangrove wetland, Northeast Coast of Bay of bengal (india): possible risks to Human health

    Energy Technology Data Exchange (ETDEWEB)

    Cabral, Henrique; Cardoso, Ines [Departamento de Biologia Animal/Instituto de Oceanografia, Campo Grande, Lisboa (Portugal); Chatterjee, Mousumi; Kumar Bhattacharya, Asok; Aftab Alam, Mohammad [Department of Marine Science, University of Calcutta, Calcutta (India); Kanta Satpathy, Kamala [Indira Gandhi Centre for Atomic Research, Environmental and Industrial Safety Section, Safety Group, Kalpakkam, Tamil Nadu (India); Kumar Sarkar, Santosh

    2008-02-15

    The suitability of using four bivalve molluscs (Sanguinolaria acuminata, Anadara granosa, Meretrix meretrix, and Pelecyora trigona) in biomonitoring of heavy metals (Cu, Pb, Cd, Zn, and Hg) collected from intertidal regions of the Sunderban mangrove wetland, northeastern part of the Bay of Bengal, were evaluated. Both speciesdependent variability and temporal variations were pronounced. A high degree of organ specificity was evident in the bivalves where gill and mantle exhibited higher metal accumulation due to ion exchange property of the mucous layer covering these organs while shells represent very poor accumulation. Elevated values of Zn and Cu reflect high potential for biomagnification through marine food chain. Metal concentrations in different body size groups of the bivalves do not follow uniform trend. Correlation coefficient between different metal couplings as tested statistically revealed significant coupling for Pb-Zn, Pb-Cu, Zn-Cu, and Hg-Cu. Concentrations of all the metals in specific organs (visceral mass, mantle and gill) of the bivalves exceeded the safe levels according to the international standards for metals compiled by Food and Agricultural Organization of the United Nations and would be of great risk for human consumption. It is concluded that the mussel and clam are suitable biomonitors to employ in programs designed to assess changes in metal pollution in the Sunderban mangrove wetland. (Abstract Copyright [2008], Wiley Periodicals, Inc.)

  11. Evaluation of the threat of marine CO2 leakage-associated acidification on the toxicity of sediment metals to juvenile bivalves

    International Nuclear Information System (INIS)

    Basallote, M. Dolores; Rodríguez-Romero, Araceli; De Orte, Manoela R.; Del Valls, T. Ángel; Riba, Inmaculada

    2015-01-01

    Highlights: • Short-term tests using juveniles of bivalves to study the effects of CO 2 dissolved. • CO 2 causes effects if the threshold concentration of the organism is overlapped. • Flows of escaped CO 2 would affect the geochemical composition of sediment–seawater. • CO 2 -induced acidification would affect differently to marine sediment toxicity. - Abstract: The effects of the acidification associated with CO 2 leakage from sub-seabed geological storage was studied by the evaluation of the short-term effects of CO 2 -induced acidification on juveniles of the bivalve Ruditapes philippinarum. Laboratory scale experiments were performed using a CO 2 -bubbling system designed to conduct ecotoxicological assays. The organisms were exposed for 10 days to elutriates of sediments collected in different littoral areas that were subjected to various pH treatments (pH 7.1, 6.6, 6.1). The acute pH-associated effects on the bivalves were observed, and the dissolved metals in the elutriates were measured. The median toxic effect pH was calculated, which ranged from 6.33 to 6.45. The amount of dissolved Zn in the sediment elutriates increased in parallel with the pH reductions and was correlated with the proton concentrations. The pH, the pCO 2 and the dissolved metal concentrations (Zn and Fe) were linked with the mortality of the exposed bivalves

  12. Late Devonian (Frasnian) bivalves from the Nocedo Formation: the results of Wilhelm Kegel’s 1927 field trip to northern Spain

    NARCIS (Netherlands)

    Amler, M.R.W.

    2010-01-01

    During a field trip to the Peña-Corada Unit of the southernmost Esla region of the Cantabrian Mountains in 1927, the German stratigrapher Wilhelm Kegel sampled brachiopods and bivalves from a section in the Laoz valley near La Ercina. The stratigraphic position is believed to be part of the Nocedo

  13. Systematics, functional morphology and distribution of a bivalve (Apachecorbula muriatica gen. et sp. nov.) from the rim of the 'Valdivia Deep' brine pool in the Red Sea

    KAUST Repository

    Oliver, Pere Graham

    2014-11-11

    The deep brine pools of the Red Sea comprise extreme, inhospitable habitats yet house microbial communities that potentially may fuel adjacent fauna. We here describe a novel bivalve from a deep-sea (1525 m) brine pool in the Red Sea, where conditions of high salinity, lowered pH, partial anoxia and high temperatures are prevalent. Remotely operated vehicle (ROV) footage showed that the bivalves were present in a narrow (20 cm) band along the rim of the brine pool, suggesting that it is not only tolerant of such extreme conditions but is also limited to them. The bivalve is a member of the Corbulidae and named Apachecorbula muriatica gen. et sp. nov. The shell is atypical of the family in being modioliform and thin. The semi-infaunal habit is seen in ROV images and reflected in the anatomy by the lack of siphons. The ctenidia are large and typical of a suspension feeding bivalve, but the absence of \\'guard cilia\\' and the greatly reduced labial palps suggest that it is non-selective as a response to low food availability. It is proposed that the low body mass observed is a consequence of the extreme habitat and low food availability. It is postulated that the observed morphology of Apachecorbula is a result of paedomorphosis driven by the effects of the extreme environment on growth but is in part mitigated by the absence of high predation pressures. © Marine Biological Association of the United Kingdom, 2014.

  14. Subcellular partitioning of cadmium in the freshwater bivalve, Pyganodon grandis, after separate short-term exposures to waterborne or diet-borne metal

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, Sophie; Hare, Landis [INRS-Eau, Terre et Environnement, Universite du Quebec, 490 rue de la Couronne, Quebec, QC, G1K 9A9 (Canada); Campbell, Peter G.C., E-mail: peter.campbell@ete.inrs.ca [INRS-Eau, Terre et Environnement, Universite du Quebec, 490 rue de la Couronne, Quebec, QC, G1K 9A9 (Canada)

    2010-11-15

    The dynamics of cadmium uptake and subcellular partitioning were studied in laboratory experiments conducted on Pyganodon grandis, a freshwater unionid bivalve that shows promise as a biomonitor for metal pollution. Bivalves were collected from an uncontaminated lake, allowed to acclimate to laboratory conditions ({>=}25 days), and then either exposed to a low, environmentally relevant, concentration of dissolved Cd (5 nM; 6, 12 and 24 h), or fed Cd-contaminated algae ({approx}70 nmol Cd g{sup -1} dry weight; 4 x 4 h). In this latter case, the bivalves were allowed to depurate for up to 8 days after the end of the feeding phase. As anticipated, the gills were the main target organ during the aqueous Cd exposure whereas the intestine was the initial site of Cd accumulation during the dietary exposure; during the subsequent depuration period, the dietary Cd accumulated in both the digestive gland and in the gills. For the gills, the distribution of Cd among the subcellular fractions (i.e., granules > heat-denatured proteins (HDP) {approx} heat-stable proteins (HSP) > mitochondria {approx} lysosomes + microsomes) was insensitive to the exposure route; both waterborne and diet-borne Cd ended up largely bound to the granule fraction. The subcellular distribution of Cd in the digestive gland differed markedly from that in the gills (HDP > HSP {approx} granules {approx} mitochondria > lysosomes + microsomes), but as in the case of the gills, this distribution was relatively insensitive to the exposure route. For both the gills and the digestive gland, the subcellular distributions of Cd differed from those observed in native bivalves that are chronically exposed to Cd in the field - in the short-term experimental exposures of P. grandis, metal detoxification was less effective than in chronically exposed native bivalves.

  15. Cephalic and limb anatomy of a new Isoxyid from the Burgess Shale and the role of "stem bivalved arthropods" in the disparity of the frontalmost appendage.

    Directory of Open Access Journals (Sweden)

    Cédric Aria

    Full Text Available We herein describe Surusicaris elegans gen. et sp. nov. (in Isoxyidae, amended, a middle (Series 3, Stage 5 Cambrian bivalved arthropod from the new Burgess Shale deposit of Marble Canyon (Kootenay National Park, British Columbia. Surusicaris exhibits 12 simple, partly undivided biramous trunk limbs with long tripartite caeca, which may illustrate a plesiomorphic "fused" condition of exopod and endopod. We construe also that the head is made of five somites (= four segments, including two eyes, one pair of anomalocaridid-like frontalmost appendages, and three pairs of poorly sclerotized uniramous limbs. This fossil may therefore be a candidate for illustrating the origin of the plesiomorphic head condition in euarthropods, and questions the significance of the "two-segmented head" in, e.g., fuxianhuiids. The frontalmost appendage in isoxyids is intriguingly disparate, bearing similarities with both dinocaridids and euarthropods. In order to evaluate the relative importance of bivalved arthropods, such as Surusicaris, in the hypothetical structuro-functional transition between the dinocaridid frontal appendage and the pre-oral-arguably deutocerebral-appendage of euarthropods, we chose a phenetic approach and computed morphospace occupancy for the frontalmost appendages of 36 stem and crown taxa. Results show different levels of evolutionary decoupling between frontalmost appendage disparity and body plans. Variance is greatest in dinocaridids and "stem bivalved" arthropods, but these groups do not occupy the morphospace homogeneously. Rather, the diversity of frontalmost appendages in "stem bivalved" arthropods, distinct in its absence of clear clustering, is found to link the morphologies of "short great appendages," chelicerae and antennules. This find fits the hypothesis of an increase in disparity of the deutocerebral appendage prior to its diversification in euarthropods, and possibly corresponds to its original time of development. The

  16. Light and scanning electron microscopic studies of Unionicola tetrafurcatus (Acari: Unionicolidae) infecting four freshwater bivalve species with referring to histopathological effect on its hosts.

    Science.gov (United States)

    Abdel-Gaber, Rewaida; Fol, Mona; Al Quraishy, Saleh

    2018-05-08

    Water mites of the genus Unionicola are the most common symbionts of freshwater bivalves. During the current investigation, a total of 120 live freshwater mussels [Corbicula fluminea (Veneroida), Coelatura aegyptiaca (Unionoidea) Mutela rostrata and Chambardia rubens (Mutelidae)], were collected from 2 localities in Tura (Helwan Governorate) and El Kanater (Qaluobiya Governorate), Egypt. Only 3 of the 4 bivalve species listed are considered freshwater bivalves (members of Unionoidea). While, C. fluminea belong to the family Cyrenidae within Veneroida. The collected mussels were dissected and examined for the presence of unionicolid mites. It was found that 30.83% (37/120) were infected with a single mite species Unionicola tetrafurcatus (Unionicolidae). The highest prevalence was observed during the summer with 83.33% (25/30), whereas the least was observed in autumn, i.e. 33.33% (10/30). Mites were recovered from the gills, gonads, and visceral mass of mussel hosts. gills of host mussels were the primary site of oviposition for unionicola mites. Smaller bivalves in size had significantly greater numbers of mites than larger ones in size. Numbers of mites per host species was variable and the highest prevalence level of 83.33% (25/30) was recorded in C. fluminea, while, the lowest one of 16.66% (5/30) was found in C. rubens. Morphological and morphometric characterizations of mites revealed some differences between the present species and other related Unionicola. Histopathological responses of host mussels to the eggs, larvae, and cuticular remnants of U. tetrafurcatus were also studied. Therefore, the present study demonstrated that freshwater bivalves have a new host and locality records for infection with U. tetrafurcatus. Future studies are recommended to include advanced molecular characteristics for these mites.

  17. Cephalic and limb anatomy of a new Isoxyid from the Burgess Shale and the role of "stem bivalved arthropods" in the disparity of the frontalmost appendage.

    Science.gov (United States)

    Aria, Cédric; Caron, Jean-Bernard

    2015-01-01

    We herein describe Surusicaris elegans gen. et sp. nov. (in Isoxyidae, amended), a middle (Series 3, Stage 5) Cambrian bivalved arthropod from the new Burgess Shale deposit of Marble Canyon (Kootenay National Park, British Columbia). Surusicaris exhibits 12 simple, partly undivided biramous trunk limbs with long tripartite caeca, which may illustrate a plesiomorphic "fused" condition of exopod and endopod. We construe also that the head is made of five somites (= four segments), including two eyes, one pair of anomalocaridid-like frontalmost appendages, and three pairs of poorly sclerotized uniramous limbs. This fossil may therefore be a candidate for illustrating the origin of the plesiomorphic head condition in euarthropods, and questions the significance of the "two-segmented head" in, e.g., fuxianhuiids. The frontalmost appendage in isoxyids is intriguingly disparate, bearing similarities with both dinocaridids and euarthropods. In order to evaluate the relative importance of bivalved arthropods, such as Surusicaris, in the hypothetical structuro-functional transition between the dinocaridid frontal appendage and the pre-oral-arguably deutocerebral-appendage of euarthropods, we chose a phenetic approach and computed morphospace occupancy for the frontalmost appendages of 36 stem and crown taxa. Results show different levels of evolutionary decoupling between frontalmost appendage disparity and body plans. Variance is greatest in dinocaridids and "stem bivalved" arthropods, but these groups do not occupy the morphospace homogeneously. Rather, the diversity of frontalmost appendages in "stem bivalved" arthropods, distinct in its absence of clear clustering, is found to link the morphologies of "short great appendages," chelicerae and antennules. This find fits the hypothesis of an increase in disparity of the deutocerebral appendage prior to its diversification in euarthropods, and possibly corresponds to its original time of development. The analysis of this

  18. Galls and gall makers in plants from the Pé-de-Gigante Cerrado Reserve, Santa Rita do Passa Quatro, SP, Brazil.

    Science.gov (United States)

    Urso-Guimarães, M V; Scareli-Santos, C

    2006-02-01

    Thirty-six morphologically different types of galls were obtained in leaves, leaflets, veins, petioles, stems, tendrils and flower buds from twenty-five species of plants in the Pé-de-Gigante Reserve, municipality of Santa Rita do Passa Quatro, state of São Paulo, Brazil. The host plant species belong to the closely related families Anacardiaceae, Annonaceae, Asteraceae, Bignoniaceae, Caryocaraceae, Erythroxylaceae, Fabaceae, Malpighiaceae, Melastomataceae, Myrtaceae, Ochnaceae, Polygalaceae, Sapindaceae, Sapotaceae, and Smilacaceae. The most common gall makers included Cecidomyiidae (Diptera), Pteromalidae (Hymenoptera) and Diaspididae (Sternorrhyncha-Hemiptera). This is the first report of galls found in the following plant genera: Gochnatia (Asteraceae), Distictela (Bignoniaceae), Banisteriopsis (Malpighiaceae), Ouratea (Ochnaceae), and Bredemeyera (Polygalaceae). The results of this work contribute to the body of knowledge about the relationship among host plants, gall makers, and the gall morphology of Pé-de-Gigante Cerrado Reserve.

  19. Galls and gall makers in plants from the Pé-de-Gigante Cerrado Reserve, Santa Rita do Passa Quatro, SP, Brazil

    Directory of Open Access Journals (Sweden)

    M. V. Urso-Guimarães

    Full Text Available Thirty-six morphologically different types of galls were obtained in leaves, leaflets, veins, petioles, stems, tendrils and flower buds from twenty-five species of plants in the Pé-de-Gigante Reserve, municipality of Santa Rita do Passa Quatro, state of São Paulo, Brazil. The host plant species belong to the closely related families Anacardiaceae, Annonaceae, Asteraceae, Bignoniaceae, Caryocaraceae, Erythroxylaceae, Fabaceae, Malpighiaceae, Melastomataceae, Myrtaceae, Ochnaceae, Polygalaceae, Sapindaceae, Sapotaceae, and Smilacaceae. The most common gall makers included Cecidomyiidae (Diptera, Pteromalidae (Hymenoptera and Diaspididae (Sternorrhyncha-Hemiptera. This is the first report of galls found in the following plant genera: Gochnatia (Asteraceae, Distictela (Bignoniaceae, Banisteriopsis (Malpighiaceae, Ouratea (Ochnaceae, and Bredemeyera (Polygalaceae. The results of this work contribute to the body of knowledge about the relationship among host plants, gall makers, and the gall morphology of Pé-de-Gigante Cerrado Reserve.

  20. In-frame seven amino-acid duplication in AIP arose over the last 3000 years, disrupts protein interaction & stability and is associated with gigantism.

    OpenAIRE

    Salvatori, R.; Radian, S.; Diekmann, Y.; Iacovazzo, D.; David, A.; Grabovska, P.; Grassi, G.; Bussell, A-M; Stals, K.; Weber, A.; Quinton, R.; Crowne, E.; Corazzini, V.; Metherell, L. A.; Kearney, T.

    2017-01-01

    OBJECTIVE: Mutations in the aryl hydrocarbon receptor-interacting protein (AIP) gene are associated with pituitary adenoma, acromegaly and gigantism. Identical alleles in unrelated pedigrees could be inherited from a common ancestor or result from recurrent mutation events. DESIGN & METHODS: Observational, inferential and experimental study, including: AIP mutation testing; reconstruction of 14 AIP-region (8.3 Mbp) haplotypes; coalescent-based approximate Bayesian estimation of the time to mo...

  1. In-frame seven amino-acid duplication in AIP arose over the last 3000 years, disrupts protein interaction and stability and is associated with gigantism

    OpenAIRE

    Salvatori, Roberto; Radian, Serban; Diekmann, Yoan; Iacovazzo, Donato; David, Alessia; Gabrovska, Plamena; Grassi, Giorgia; Bussell, Anna-Marie; Stals, Karen; Weber, Astrid; Quinton, Richard; Crowne, Elizabeth C; Corazzini, Valentina; Metherell, Lou; Kearney, Tara

    2017-01-01

    Objective Mutations in the aryl hydrocarbon receptor-interacting protein (AIP) gene are associated with pituitary adenoma, acromegaly and gigantism. Identical alleles in unrelated pedigrees could be inherited from a common ancestor or result from recurrent mutation events. Design and methods Observational, inferential and experimental study, including: AIP mutation testing; reconstruction of 14 AIP-region (8.3?Mbp) haplotypes; coalescent-based approximate Bayesian estimation of the time to mo...

  2. Interactive effects of pH and metals on mitochondrial functions of intertidal bivalves Crassostrea virginica and Mercenaria mercenaria

    International Nuclear Information System (INIS)

    Ivanina, Anna V.; Sokolova, Inna M.

    2013-01-01

    Highlights: •Interactive effects of trace metals Cd and Cu and pH were studied in mitochondria of clams and oysters. •Mitochondrial respiration and membrane potential of bivalves were robust to pH variation (6.6–7.8). •Elevated levels of Cd and Cu inhibited mitochondrial respiration in the pH-dependent manner but did not affect the membrane potential. •Negative effects of Cd and Cd on mitochondrial respiration were alleviated at low pH (7.0 and below). •Moderate acidosis may protect molluscan mitochondria from metal toxicity. -- Abstract: Intertidal bivalves experience broad fluctuations of environmental temperature, pH and oxygen content which could change their intracellular pH. They are also exposed to trace metals such as cadmium (Cd) and copper (Cu) that accumulate in their tissues and may negatively affect mitochondrial functions and bioenergetics. We determined the interactive effects of pH and trace metals (25 μM Cd or Cu) on mitochondrial functions (including respiration and membrane potentials in both ADP-stimulated (state 3) and resting (state 4) states) of two common marine bivalves, the hard clams (Mercenaria mercenaria) and eastern oysters (Crassostrea virginica). In the absence of the trace metals, mitochondrial functions of C. virginica and M. mercenaria were insensitive to pH in a broad physiologically relevant range (6.6–7.8). Mitochondrial respiration was generally suppressed by 25 μM Cd or Cu (with the stronger effects observed for ADP-stimulated compared to the resting respiration) while the mitochondrial membrane potential was unaffected. pH modulated the effects of Cu and Cd on mitochondrial respiration of the bivalves. In oysters, Cu suppressed ADP-stimulated mitochondrial respiration at high and low pH values (6.6 and 7.8, respectively), but had no effect in the intermediate pH range (7.0–7.4). In clams, the negative effect of Cu on ADP-stimulated respiration was only observed at extremely high pH (7.8). A decrease in p

  3. Metals and pesticides in commercial bivalve mollusc production areas in the North and South Bays, Santa Catarina (Brazil).

    Science.gov (United States)

    de Souza, R V; Garbossa, L H P; Campos, C J A; Vianna, L F de N; Vanz, A; Rupp, G S

    2016-04-15

    Concentrations of heavy metals were quantified in mussels Perna perna and Pacific oysters Crassostrea gigas in 28 cultivation sites in the North and South Bays, SC (Brazil). Concentrations of pesticides were also quantified in these bivalve, water and sediment samples collected in 14 cultivation sites on four occasions in the period October 2012-October 2013. Pesticides were not detected in any of the mussel, oyster, water or sediment samples. The South Bay was found to be generally more contaminated with As while the North Bay showed higher concentrations of Ni. Concentrations of Pb and Cd were below the limit of detection of the method (0.5mg/kg) in all samples. Mussels accumulated more As and Ni than oysters, while the opposite was observed for Cu. Metal concentrations were below the maximum levels for foodstuffs specified in the Brazilian legislation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Bivalve fouling of nuclear power plant service-water systems. Volume 2. Current status of biofouling surveillance and control techniques

    International Nuclear Information System (INIS)

    Daling, P.M.; Johnson, K.I.

    1985-03-01

    This report describes the current status of techniques for detection and control of cooling-water system fouling by bivalve mollusks at nuclear power plants. The effectiveness of these techniques is evaluated on the basis of information gathered from a literature review and in interviews with nuclear power plant personnel. Biofouling detection techniques examined in this report include regular maintenance, in-service inspection, and testing. Generally, these methods have been inadequate for detecting biofouling. Recommendations for improving biofouling detection capabilities are presented. Biofouling prevention (or control) methods that are examined in this report include intake screen systems, thermal treatment, preventive maintenance, chemical treatment alternatives, and antifoulant coatings. Recommendations for improving biofouling control methods at operating nuclear power plants are presented. Additional techniques that could be implemented at future power plants or that require further research are also described

  5. Interactive effects of pH and metals on mitochondrial functions of intertidal bivalves Crassostrea virginica and Mercenaria mercenaria

    Energy Technology Data Exchange (ETDEWEB)

    Ivanina, Anna V.; Sokolova, Inna M., E-mail: isokolov@uncc.edu

    2013-11-15

    Highlights: •Interactive effects of trace metals Cd and Cu and pH were studied in mitochondria of clams and oysters. •Mitochondrial respiration and membrane potential of bivalves were robust to pH variation (6.6–7.8). •Elevated levels of Cd and Cu inhibited mitochondrial respiration in the pH-dependent manner but did not affect the membrane potential. •Negative effects of Cd and Cd on mitochondrial respiration were alleviated at low pH (7.0 and below). •Moderate acidosis may protect molluscan mitochondria from metal toxicity. -- Abstract: Intertidal bivalves experience broad fluctuations of environmental temperature, pH and oxygen content which could change their intracellular pH. They are also exposed to trace metals such as cadmium (Cd) and copper (Cu) that accumulate in their tissues and may negatively affect mitochondrial functions and bioenergetics. We determined the interactive effects of pH and trace metals (25 μM Cd or Cu) on mitochondrial functions (including respiration and membrane potentials in both ADP-stimulated (state 3) and resting (state 4) states) of two common marine bivalves, the hard clams (Mercenaria mercenaria) and eastern oysters (Crassostrea virginica). In the absence of the trace metals, mitochondrial functions of C. virginica and M. mercenaria were insensitive to pH in a broad physiologically relevant range (6.6–7.8). Mitochondrial respiration was generally suppressed by 25 μM Cd or Cu (with the stronger effects observed for ADP-stimulated compared to the resting respiration) while the mitochondrial membrane potential was unaffected. pH modulated the effects of Cu and Cd on mitochondrial respiration of the bivalves. In oysters, Cu suppressed ADP-stimulated mitochondrial respiration at high and low pH values (6.6 and 7.8, respectively), but had no effect in the intermediate pH range (7.0–7.4). In clams, the negative effect of Cu on ADP-stimulated respiration was only observed at extremely high pH (7.8). A decrease in p

  6. Gene expression and physiological changes of different populations of the long-lived bivalve Arctica islandica under low oxygen conditions.

    Directory of Open Access Journals (Sweden)

    Eva E R Philipp

    Full Text Available The bivalve Arctica islandica is extremely long lived (>400 years and can tolerate long periods of hypoxia and anoxia. European populations differ in maximum life spans (MLSP from 40 years in the Baltic to >400 years around Iceland. Characteristic behavior of A. islandica involves phases of metabolic rate depression (MRD during which the animals burry into the sediment for several days. During these phases the shell water oxygen concentrations reaches hypoxic to anoxic levels, which possibly support the long life span of some populations. We investigated gene regulation in A. islandica from a long-lived (MLSP 150 years German Bight population and the short-lived Baltic Sea population, experimentally exposed to different oxygen levels. A new A. islandica transcriptome enabled the identification of genes important during hypoxia/anoxia events and, more generally, gene mining for putative stress response and (anti- aging genes. Expression changes of a antioxidant defense: Catalase, Glutathione peroxidase, manganese and copper-zinc Superoxide dismutase; b oxygen sensing and general stress response: Hypoxia inducible factor alpha, Prolyl hydroxylase and Heat-shock protein 70; and c anaerobic capacity: Malate dehydrogenase and Octopine dehydrogenase, related transcripts were investigated. Exposed to low oxygen, German Bight individuals suppressed transcription of all investigated genes, whereas Baltic Sea bivalves enhanced gene transcription under anoxic incubation (0 kPa and, further, decreased these transcription levels again during 6 h of re-oxygenation. Hypoxic and anoxic exposure and subsequent re-oxygenation in Baltic Sea animals did not lead to increased protein oxidation or induction of apoptosis, emphasizing considerable hypoxia/re-oxygenation tolerance in this species. The data suggest that the energy saving effect of MRD may not be an attribute of Baltic Sea A. islandica chronically exposed to high environmental variability (oxygenation

  7. The mismatch between bioaccumulation in field and laboratory environments: Interpreting the differences for metals in benthic bivalves

    International Nuclear Information System (INIS)

    Belzunce-Segarra, Maria J.; Simpson, Stuart L.; Amato, Elvio D.; Spadaro, David A.; Hamilton, Ian L.; Jarolimek, Chad V.; Jolley, Dianne F.

    2015-01-01

    Laboratory-based bioaccumulation and toxicity bioassays are frequently used to predict the ecological risk of contaminated sediments in the field. This study investigates the bioassay conditions most relevant to achieving environmentally relevant field exposures. An identical series of metal-contaminated marine sediments were deployed in the field and laboratory over 31 days. Changes in metal concentrations and partitioning in both sediments and waters were used to interpret differences in metal exposure and bioaccumulation to the benthic bivalve Tellina deltoidalis. Loss of resuspended sediments and deposition of suspended particulate matter from the overlying water resulted in the concentrations of Cu, Pb and Zn (major contaminants) becoming lower in the 1-cm surface layer of field-deployed sediments. Lower exchange rates of overlying waters in the laboratory resulted in higher dissolved metal exposures. The prediction of metal bioaccumulation by the bivalves in field and laboratory was improved by considering the metal partitioning within the surface sediments. - Highlights: • Particulate metals are the dominant metal exposure route in laboratory and field tests (87). • There is an over-representation of the dissolved metal exposure in the laboratory (81). • Laboratory bioassays result in higher bioaccumulation of major metals, Cu, Pb, Zn (82). • Differences in exposure must be considered for a proper sediment quality evaluation (83). • Traditional measurements are not sufficient to explain bioaccumulation results (79). - To improve the value of field- and laboratory-based sediment bioassays in ecological risk assessments, it is necessary to create exposure conditions that resemble those in the field

  8. Hypoxia and acidification have additive and synergistic negative effects on the growth, survival, and metamorphosis of early life stage bivalves.

    Science.gov (United States)

    Gobler, Christopher J; DePasquale, Elizabeth L; Griffith, Andrew W; Baumann, Hannes

    2014-01-01

    Low oxygen zones in coastal and open ocean ecosystems have expanded in recent decades, a trend that will accelerate with climatic warming. There is growing recognition that low oxygen regions of the ocean are also acidified, a condition that will intensify with rising levels of atmospheric CO2. Presently, however, the concurrent effects of low oxygen and acidification on marine organisms are largely unknown, as most prior studies of marine hypoxia have not considered pH levels. We experimentally assessed the consequences of hypoxic and acidified water for early life stage bivalves (bay scallops, Argopecten irradians, and hard clams, Mercenaria mercenaria), marine organisms of significant economic and ecological value and sensitive to climate change. In larval scallops, experimental and naturally-occurring acidification (pH, total scale  = 7.4-7.6) reduced survivorship (by >50%), low oxygen (30-50 µM) inhibited growth and metamorphosis (by >50%), and the two stressors combined produced additively negative outcomes. In early life stage clams, however, hypoxic waters led to 30% higher mortality, while acidified waters significantly reduced growth (by 60%). Later stage clams were resistant to hypoxia or acidification separately but experienced significantly (40%) reduced growth rates when exposed to both conditions simultaneously. Collectively, these findings demonstrate that the consequences of low oxygen and acidification for early life stage bivalves, and likely other marine organisms, are more severe than would be predicted by either individual stressor and thus must be considered together when assessing how ocean animals respond to these conditions both today and under future climate change scenarios.

  9. Molecular phylogeny of the bivalve superfamily Galeommatoidea (Heterodonta, Veneroida) reveals dynamic evolution of symbiotic lifestyle and interphylum host switching

    Science.gov (United States)

    2012-01-01

    Background Galeommatoidea is a superfamily of bivalves that exhibits remarkably diverse lifestyles. Many members of this group live attached to the body surface or inside the burrows of other marine invertebrates, including crustaceans, holothurians, echinoids, cnidarians, sipunculans and echiurans. These symbiotic species exhibit high host specificity, commensal interactions with hosts, and extreme morphological and behavioral adaptations to symbiotic life. Host specialization to various animal groups has likely played an important role in the evolution and diversification of this bivalve group. However, the evolutionary pathway that led to their ecological diversity is not well understood, in part because of their reduced and/or highly modified morphologies that have confounded traditional taxonomy. This study elucidates the taxonomy of the Galeommatoidea and their evolutionary history of symbiotic lifestyle based on a molecular phylogenic analysis of 33 galeommatoidean and five putative galeommatoidean species belonging to 27 genera and three families using two nuclear ribosomal genes (18S and 28S ribosomal DNA) and a nuclear (histone H3) and mitochondrial (cytochrome oxidase subunit I) protein-coding genes. Results Molecular phylogeny recovered six well-supported major clades within Galeommatoidea. Symbiotic species were found in all major clades, whereas free-living species were grouped into two major clades. Species symbiotic with crustaceans, holothurians, sipunculans, and echiurans were each found in multiple major clades, suggesting that host specialization to these animal groups occurred repeatedly in Galeommatoidea. Conclusions Our results suggest that the evolutionary history of host association in Galeommatoidea has been remarkably dynamic, involving frequent host switches between different animal phyla. Such an unusual pattern of dynamic host switching is considered to have resulted from their commensalistic lifestyle, in which they maintain filter

  10. Ultrasound assisted enzymatic hydrolysis for isolating titanium dioxide nanoparticles from bivalve mollusk before sp-ICP-MS.

    Science.gov (United States)

    Taboada-López, María Vanesa; Iglesias-López, Sara; Herbello-Hermelo, Paloma; Bermejo-Barrera, Pilar; Moreda-Piñeiro, Antonio

    2018-08-14

    Applicability of single-particle inductively coupled plasma mass spectrometry (sp-ICP-MS) using dwell times equal to or shorter than 100 μs has been tested for assessing titanium dioxide nanoparticles (TiO 2 NPs) in bivalve mollusks. TiO 2 NPs isolation from fresh mollusk tissues was achieved by ultrasound assisted enzymatic hydrolysis procedure using a pancreatin/lipase mixture. Optimum extraction conditions imply ultrasonication (60% amplitude) for 10 min, and 7.5 mL of a solution containing 3.0 g L -1 of pancreatin and lipase (pH 7.4). The developed method was found to be repeatable (repeatability of 17% for the over-all procedure, TiO 2 NPs concentration of 5.33 × 10 7  ± 8.89 × 10 6 , n = 11), showing a limit of detection of 5.28 × 10 6 NPs g -1 , and a limit of detection in size of 24.4-30.4 nm, based on the 3σ criteria, and on the 3σ/5 σ criteria, respectively. The analytical recovery within the 90-99% range (use of TiO 2 NPs standards of 50 nm at 7 and 14 μg L -1 as Ti). Several bivalve mollusks (clams, cockles, mussels, razor clams, oysters and variegated scallops) were analyzed for total titanium (ICP-MS after microwave assisted acid digestion), and for TiO 2 NPs by the proposed method. TiO 2 NPs concentrations were within the 2.36 × 10 7 -1.25 × 10 8 NPs g -1 range, and the most frequent sizes were from 50 to 70 nm. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Validation of the flow-through chamber (FTC and steady-state (SS methods for clearance rate measurements in bivalves

    Directory of Open Access Journals (Sweden)

    Poul S. Larsen

    2011-09-01

    To obtain precise and reliable laboratory clearance rate (filtration rate measurements with the ‘flow-through chamber method’ (FTC the design must ensure that only inflow water reaches the bivalve's inhalant aperture and that exit flow is fully mixed. As earlier recommended these prerequisites can be checked by a plot of clearance rate (CR versus increasing through-flow (Fl to reach a plateau, which is the true CR, but we also recommend to plot percent particles cleared versus reciprocal through-flow where the plateau becomes the straight line CR/Fl, and we emphasize that the percent of particles cleared is in itself neither a criterion for valid CR measurement, nor an indicator of appropriate ‘chamber geometry’ as hitherto adapted in many studies. For the ‘steady-state method’ (SS, the design must ensure that inflow water becomes fully mixed with the bivalve's excurrent flow to establish a uniform chamber concentration prevailing at its incurrent flow and at the chamber outlet. These prerequisites can be checked by a plot of CR versus increasing Fl, which should give the true CR at all through-flows. Theoretically, the experimental uncertainty of CR for a given accuracy of concentration measurements depends on the percent reduction in particle concentration (100×P from inlet to outlet of the ideal ‘chamber geomety’. For FTC, it decreases with increasing values of P while for SS it first decreases but then increases again, suggesting the use of an intermediate value of P. In practice, the optimal value of P may depend on the given ‘chamber geometry’. The fundamental differences between the FTC and the SS methods and practical guidelines for their use are pointed out, and new data on CR for the blue mussel, Mytilus edulis, illustrate a design and use of the SS method which may be employed in e.g. long-term growth experiments at constant algal concentrations.

  12. Molecular phylogeny of the bivalve superfamily Galeommatoidea (Heterodonta, Veneroida reveals dynamic evolution of symbiotic lifestyle and interphylum host switching

    Directory of Open Access Journals (Sweden)

    Goto Ryutaro

    2012-09-01

    Full Text Available Abstract Background Galeommatoidea is a superfamily of bivalves that exhibits remarkably diverse lifestyles. Many members of this group live attached to the body surface or inside the burrows of other marine invertebrates, including crustaceans, holothurians, echinoids, cnidarians, sipunculans and echiurans. These symbiotic species exhibit high host specificity, commensal interactions with hosts, and extreme morphological and behavioral adaptations to symbiotic life. Host specialization to various animal groups has likely played an important role in the evolution and diversification of this bivalve group. However, the evolutionary pathway that led to their ecological diversity is not well understood, in part because of their reduced and/or highly modified morphologies that have confounded traditional taxonomy. This study elucidates the taxonomy of the Galeommatoidea and their evolutionary history of symbiotic lifestyle based on a molecular phylogenic analysis of 33 galeommatoidean and five putative galeommatoidean species belonging to 27 genera and three families using two nuclear ribosomal genes (18S and 28S ribosomal DNA and a nuclear (histone H3 and mitochondrial (cytochrome oxidase subunit I protein-coding genes. Results Molecular phylogeny recovered six well-supported major clades within Galeommatoidea. Symbiotic species were found in all major clades, whereas free-living species were grouped into two major clades. Species symbiotic with crustaceans, holothurians, sipunculans, and echiurans were each found in multiple major clades, suggesting that host specialization to these animal groups occurred repeatedly in Galeommatoidea. Conclusions Our results suggest that the evolutionary history of host association in Galeommatoidea has been remarkably dynamic, involving frequent host switches between different animal phyla. Such an unusual pattern of dynamic host switching is considered to have resulted from their commensalistic lifestyle, in

  13. Coexisting diseases modifying each other’s presentation - lack of growth failure in Turner syndrome due to the associated pituitary gigantism.

    Science.gov (United States)

    Dragović, Tamara; Đuran, Zorana; Jelić, Svetlana; Marinković, Dejan; Kiković, Saša; Kuzmić-Janković, Snežana; Hajduković, Zoran

    2016-10-01

    Turner syndrome presents with one of the most frequent chromosomal aberrations in female, typically presented with growth retardation, ovarian insufficiency, facial dysmorphism, and numerous other somatic stigmata. Gigantism is an extremely rare condition resulting from an excessive growth hormone (GH) secretion that occurs during childhood before the fusion of epiphyseal growth plates. The major clinical feature of gigantism is growth acceleration, although these patients also suffer from hypogonadism and soft tissue hypertrophy. We presented a girl with mosaic Turner syndrome, delayed puberty and normal linear growth for the sex and age, due to the simultaneous GH hypersecretion by pituitary tumor. In the presented case all the typical phenotypic stigmata related to Turner syndrome were missing. Due to excessive pituitary GH secretion during the period while the epiphyseal growth plates of the long bones are still open, characteristic stagnation in longitudinal growth has not been demonstrated. The patient presented with delayed puberty and primary amenorrhea along with a sudden appearance of clinical signs of hypersomatotropinism, which were the reasons for seeking medical help at the age of 16. Physical examination of children presenting with delayed puberty but without growth arrest must include an overall hormonal and genetic testing even in the cases when typical clinical presentations of genetic disorder are absent. To the best of our knowledge, this is the first reported case of simultaneous presence of Turner syndrome and gigantism in the literature.

  14. Coexisting diseases modifying each other’s presentation - lack of growth failure in Turner syndrome due to the associated pituitary gigantism

    Directory of Open Access Journals (Sweden)

    Dragović Tamara

    2016-01-01

    Full Text Available Introduction. Turner syndrome presents with one of the most frequent chromosomal aberrations in female, typically presented with growth retardation, ovarian insufficiency, facial dysmorphism, and numerous other somatic stigmata. Gigantism is an extremely rare condition resulting from an excessive growth hormone (GH secretion that occurs during childhood before the fusion of epiphyseal growth plates. The major clinical feature of gigantism is growth acceleration, although these patients also suffer from hypogonadism and soft tissue hypertrophy. Case report. We presented a girl with mosaic Turner syndrome, delayed puberty and normal linear growth for the sex and age, due to the simultaneous GH hypersecretion by pituitary tumor. In the presented case all the typical phenotypic stigmata related to Turner syndrome were missing. Due to excessive pituitary GH secretion during the period while the epiphyseal growth plates of the long bones are still open, characteristic stagnation in longitudinal growth has not been demonstrated. The patient presented with delayed puberty and primary amenorrhea along with a sudden appearance of clinical signs of hypersomatotropinism, which were the reasons for seeking medical help at the age of 16. Conclusion. Physical examination of children presenting with delayed puberty but without growth arrest must include an overall hormonal and genetic testing even in the cases when typical clinical presentations of genetic disorder are absent. To the best of our knowledge, this is the first reported case of simultaneous presence of Turner syndrome and gigantism in the literature.

  15. Análise química do bambu-gigante (Dendrocalamus giganteus Wall. ex Munro em diferentes idades

    Directory of Open Access Journals (Sweden)

    Nelson Potenciano Marinho

    2012-06-01

    Full Text Available http://dx.doi.org/10.5902/198050985749O bambu é uma planta monocotiledônea de origem tropical, de rápido crescimento, sendo considerado um importante regenerador ambiental devido ao seu sistema radicular. O Dendrocalamus giganteus é popularmente conhecido por bambu-gigante, sendo uma espécie entouceirante de grande porte, cujos colmos podem variar de 24 a 40 metros de altura, com diâmetros entre 10 e 20 cm. Esse trabalho teve como objetivo analisar quimicamente os colmos do bambu-gigante visando fornecer informações sobre a sua composição química nas idades de 2 a 6 anos. Os colmos do bambu foram coletados na área Experimental Agrícola do Departamento de Engenharia Mecânica da UNESP-Bauru, onde é realizado o manejo sistemático de diversas espécies de bambu para fins de pesquisas e divulgação dessa planta. Foram retiradas amostras da base entre bambus com idade de 2 a 6 anos de uma mesma touceira, totalizando 5 amostras, com 2 metros de altura cada, colhidas na lua minguante no mês de março. As análises químicas foram feitas com os entrenós, utilizando as normas e procedimentos da TAPPI. A porcentagem média de extrativos em água quente, extrativos em água fria, extrativos totais e teor de cinzas não apresentaram relação direta com a idade. A maior porcentagem de extrativos em água quente, com valor de 12,04%, extrativos em água fria, com 10,25%, e extrativos totais, com 12,91%, foi observada aos 2 anos de idade. A maior porcentagem de cinzas foi obtida aos três anos, com valores de 1,09%. O teor médio de extrativos em NaOH diminui de 25,72% aos dois anos para 20,17% aos seis anos de idade. O mesmo comportamento foi observado para os extrativos em etanol tolueno, diminuindo de 10,91% para 4,61%. O teor médio de lignina não sofreu influência da idade, variando de 22,66 a 24,11%.

  16. Reconstrucción cervical tras resección de neurofibroma solitario gigante con colgajo anterolateral de muslo

    Directory of Open Access Journals (Sweden)

    Mauricio Mendieta-Espinosa

    Full Text Available Los tumores de cabeza y cuello son un grupo heterogéneo; los neurofibromas pueden originarse de cualquier nervio independientemente de su localización, incluyendo nervios periféricos o intracraneales y se dividen en 4 tipos. Los solitarios son tumores confinados, espontáneos y prácticamente sin ninguna manifestación. Anatómicamente, los neurofibromas del cuello son relativamente raros, con un crecimiento lento e indoloro. Presentamos el caso de un paciente varón de 41 años de edad, remitido a nuestra consulta por presentar neurofibroma solitario gigante en la base del lado izquierdo del cuello, de 10 cm de diámetro, con zona central ulcerada y sangrados intermitentes, adherido a planos profundos, de 30 años de evolución y que había sido tratado en 3 ocasiones con resecciones parciales y cubertura con colgajo acromial. Practicamos resección completa de la tumoración y reconstrucción inmediata con colgajo anterolateral de muslo, logrando la mejoría estético-funcional de la zona cervical y sin complicaciones.

  17. Herbivory and body size: allometries of diet quality and gastrointestinal physiology, and implications for herbivore ecology and dinosaur gigantism.

    Science.gov (United States)

    Clauss, Marcus; Steuer, Patrick; Müller, Dennis W H; Codron, Daryl; Hummel, Jürgen

    2013-01-01

    Digestive physiology has played a prominent role in explanations for terrestrial herbivore body size evolution and size-driven diversification and niche differentiation. This is based on the association of increasing body mass (BM) with diets of lower quality, and with putative mechanisms by which a higher BM could translate into a higher digestive efficiency. Such concepts, however, often do not match empirical data. Here, we review concepts and data on terrestrial herbivore BM, diet quality, digestive physiology and metabolism, and in doing so give examples for problems in using allometric analyses and extrapolations. A digestive advantage of larger BM is not corroborated by conceptual or empirical approaches. We suggest that explanatory models should shift from physiological to ecological scenarios based on the association of forage quality and biomass availability, and the association between BM and feeding selectivity. These associations mostly (but not exclusively) allow large herbivores to use low quality forage only, whereas they allow small herbivores the use of any forage they can physically manage. Examples of small herbivores able to subsist on lower quality diets are rare but exist. We speculate that this could be explained by evolutionary adaptations to the ecological opportunity of selective feeding in smaller animals, rather than by a physiologic or metabolic necessity linked to BM. For gigantic herbivores such as sauropod dinosaurs, other factors than digestive physiology appear more promising candidates to explain evolutionary drives towards extreme BM.

  18. Herbivory and body size: allometries of diet quality and gastrointestinal physiology, and implications for herbivore ecology and dinosaur gigantism.

    Directory of Open Access Journals (Sweden)

    Marcus Clauss

    Full Text Available Digestive physiology has played a prominent role in explanations for terrestrial herbivore body size evolution and size-driven diversification and niche differentiation. This is based on the association of increasing body mass (BM with diets of lower quality, and with putative mechanisms by which a higher BM could translate into a higher digestive efficiency. Such concepts, however, often do not match empirical data. Here, we review concepts and data on terrestrial herbivore BM, diet quality, digestive physiology and metabolism, and in doing so give examples for problems in using allometric analyses and extrapolations. A digestive advantage of larger BM is not corroborated by conceptual or empirical approaches. We suggest that explanatory models should shift from physiological to ecological scenarios based on the association of forage quality and biomass availability, and the association between BM and feeding selectivity. These associations mostly (but not exclusively allow large herbivores to use low quality forage only, whereas they allow small herbivores the use of any forage they can physically manage. Examples of small herbivores able to subsist on lower quality diets are rare but exist. We speculate that this could be explained by evolutionary adaptations to the ecological opportunity of selective feeding in smaller animals, rather than by a physiologic or metabolic necessity linked to BM. For gigantic herbivores such as sauropod dinosaurs, other factors than digestive physiology appear more promising candidates to explain evolutionary drives towards extreme BM.

  19. Dorsal resection of a thoracic hemivertebra in a 4-year-old boy with endochondral gigantism. A case report.

    Science.gov (United States)

    Zarghooni, Kourosh; Sobotrke, Rolf; Schmidt, Heinrich; Rollinghoff, Marc; Siewe, Jan; Eysel, Peer

    2010-10-01

    The authors present what appears to be the first case of congenital kyphosis due to a T12 hemivertebra in a four-year-old boy with endochondral gigantism syndrome of unknown origin. Because of his overgrowth, the patient had severe medical and orthopaedic problems and was almost immobile. Prior to surgery, he experienced a rapidly progressive thoracolumbar kyphosis to 600 (T10-L2). MRI of the brain and spine showed critical protraction of the spinal cord and myelopathy from compression at T12. Single-stage posterior resection of the hemivertebra with spinal shortening and dorsal transpedicular instrumentation of T10-L2 was performed. Although the bone tissue was cartilaginous and dysplastic, 420 (30%) correction was achieved along with decompression of the spinal canal. The patient experienced no neurological impairment post-operatively. At follow-up examination 1.5 year after surgery, the patient's movement disorder had improved markedly and he was able to stand and walk. This very rare case demonstrates that single-stage posterior hemivertebra resection and transpedicular instrumentation for correction of congenital kyphosis can be a safe and effective procedure even in a very challenging case.

  20. Predation as the primary selective force in recurrent evolution of gigantism in Poecilozonites land snails in Quaternary Bermuda

    Science.gov (United States)

    Olson, Storrs L.; Hearty, Paul J.

    2010-01-01

    During the last half million years, pulses of gigantism in the anagenetic lineage of land snails of the subgenus Poecilozonites on Bermuda were correlated with glacial periods when lower sea level resulted in an island nearly an order of magnitude larger than at present. During those periods, the island was colonized by large vertebrate predators that created selection pressure for large size and rapid growth in the snails. Extreme reduction in land area from rising seas, along with changes in ecological conditions at the onset of interglacial episodes, marked extinction events for large predators, after which snails reverted to much smaller size. The giant snails were identical in morphology during the last two glacials when the predators included a large flightless rail Rallus recessus (marine isotope stages (MIS) 4-2) and a crane Grus latipes and a duck Anas pachysceles (MIS 6). In a preceding glacial period (MIS 10), when the fauna also included the tortoise Hesperotestudo bermudae, the snails were not only large, but the shells were much thicker, presumably to prevent crushing by tortoises. Evolution of Poecilozonites provides an outstanding example of dramatic morphological change in response to environmental pressures in the absence of cladogenesis. PMID:20554560

  1. Gigantic perpendicular magnetic anisotropy of heavy transition metal cappings on Fe/MgO(0 0 1)

    Science.gov (United States)

    Taivansaikhan, P.; Odkhuu, D.; Rhim, S. H.; Hong, S. C.

    2017-11-01

    Effects of capping layer by 5d transition metals (TM = Hf, Ta, W, Re, Os, Ir, Pt, and Au) on Fe/MgO(0 0 1), a typical magnetic tunneling junction, are systematically investigated using first-principles calculation for magnetism and magnetocrystalline-anisotropy (MCA). The early TMs having less than half-filled d bands favor magnetization antiparallel to Fe, whereas the late TMs having more than half-filled d bands favor parallel, which is explained in the framework of kinetic exchange energy. The Os capping, isovalent to Fe, enhances MCA significantly to gigantic energy of +11.31 meV/cell, where positive contribution is mostly from the partially filled majority d bands of magnetic quantum number of |m| = 1 along with stronger spin-orbit coupling of Os than Fe. Different TM cappings give different MCA energies as the Fermi level shifts according to the valence of TM: Re and Ir, just one valence more or less than Os, have still large PMCA but smaller than the Os. In the W and Pt cappings, valence difference by two, PMCA are further reduced; MCAs are lowered compared to Fe/MgO(0 0 1) by the cappings of the very early TMs (Hf and Ta), while the very late TM (Au) switches sign to in-plane MCA.

  2. The quagga mussel (Dreissena rostriformis bugensis Andrusov, 1897 – another Ponto-Caspian dreissenid bivalve in the southern Baltic catchment: the first record from the Szczecin Lagoon

    Directory of Open Access Journals (Sweden)

    Adam Woźniczka

    2016-04-01

    Full Text Available In 2014, a non-indigenous dreissenid bivalve, the quagga mussel (Dreissena rostriformis bugensis Andrusov, 1897 was for the first time recorded in the Szczecin Lagoon. This was also the first record of the species in the Baltic Sea catchment. The quagga mussel was found to accompany the zebra mussel (Dreissena polymorpha, a non-indigenous bivalve already firmly established in the Lagoon. As indicated by the new immigrant's estimated abundance (4000.0 ± 355.44 ind. m−2 and the zebra mussel to quagga mussel abundance ratio (about 60:40, the immigration of D. rostriformis bugensis to the Lagoon can be regarded as successful. The quagga mussel has already formed a strong and reproducing population which co-occurs with that of the zebra mussel in the area.

  3. Transgenerational exposure of North Atlantic bivalves to ocean acidification renders offspring more vulnerable to low pH and additional stressors.

    Science.gov (United States)

    Griffith, Andrew W; Gobler, Christopher J

    2017-09-12

    While early life-stage marine bivalves are vulnerable to ocean acidification, effects over successive generations are poorly characterized. The objective of this work was to assess the transgenerational effects of ocean acidification on two species of North Atlantic bivalve shellfish, Mercenaria mercenaria and Argopecten irradians. Adults of both species were subjected to high and low pCO 2 conditions during gametogenesis. Resultant larvae were exposed to low and ambient pH conditions in addition to multiple, additional stressors including thermal stress, food-limitation, and exposure to a harmful alga. There were no indications of transgenerational acclimation to ocean acidification during experiments. Offspring of elevated pCO 2 -treatment adults were significantly more vulnerable to acidification as well as the additional stressors. Our results suggest that clams and scallops are unlikely to acclimate to ocean acidification over short time scales and that as coastal oceans continue to acidify, negative effects on these populations may become compounded and more severe.

  4. Evaluation of the threat of marine CO{sub 2} leakage-associated acidification on the toxicity of sediment metals to juvenile bivalves

    Energy Technology Data Exchange (ETDEWEB)

    Basallote, M. Dolores, E-mail: dolores.basallote@uca.es [Cátedra UNESCO/UNITWIN WiCop, Departamento de Química-Física, Facultad de Ciencias del Mar y Ambientales, Universidad de Cádiz, Polígono Río San Pedro s/n, 11510 Puerto Real, Cádiz (Spain); Rodríguez-Romero, Araceli [Departamento de Ecología y Gestión Costera, Instituto de Ciencias Marinas de Andalucía (CSIC), Campus Río San Pedro, 11510 Puerto Real, Cádiz (Spain); De Orte, Manoela R.; Del Valls, T. Ángel; Riba, Inmaculada [Cátedra UNESCO/UNITWIN WiCop, Departamento de Química-Física, Facultad de Ciencias del Mar y Ambientales, Universidad de Cádiz, Polígono Río San Pedro s/n, 11510 Puerto Real, Cádiz (Spain)

    2015-09-15

    Highlights: • Short-term tests using juveniles of bivalves to study the effects of CO{sub 2} dissolved. • CO{sub 2} causes effects if the threshold concentration of the organism is overlapped. • Flows of escaped CO{sub 2} would affect the geochemical composition of sediment–seawater. • CO{sub 2}-induced acidification would affect differently to marine sediment toxicity. - Abstract: The effects of the acidification associated with CO{sub 2} leakage from sub-seabed geological storage was studied by the evaluation of the short-term effects of CO{sub 2}-induced acidification on juveniles of the bivalve Ruditapes philippinarum. Laboratory scale experiments were performed using a CO{sub 2}-bubbling system designed to conduct ecotoxicological assays. The organisms were exposed for 10 days to elutriates of sediments collected in different littoral areas that were subjected to various pH treatments (pH 7.1, 6.6, 6.1). The acute pH-associated effects on the bivalves were observed, and the dissolved metals in the elutriates were measured. The median toxic effect pH was calculated, which ranged from 6.33 to 6.45. The amount of dissolved Zn in the sediment elutriates increased in parallel with the pH reductions and was correlated with the proton concentrations. The pH, the pCO{sub 2} and the dissolved metal concentrations (Zn and Fe) were linked with the mortality of the exposed bivalves.

  5. Ecological studies of wood-boring bivalves in the vicinity of the Oyster Creek Nuclear Generating Station. Progress report Sep-Nov 81

    International Nuclear Information System (INIS)

    Hoagland, K.E.; Crocket, L.

    1982-06-01

    The species composition, distribution, and population dynamics of wood-boring bivalves are being studied in the vicinity of the Oyster Creek Nuclear Generating Station, Barnegat Bay, New Jersey. Untreated wood test panels are used to collect organisms at 12 stations. Physiological tolerances of 3 species are also under investigation in the laboratory. Competition among the species is being analyzed. In the fall of 1981, Teredo bartschi remained in Oyster Creek despite continuous prolonged outages of the Oyster Creek Nuclear Generating Station

  6. Carbon and nitrogen elemental and isotopic ratios of filter-feeding bivalves along the French coasts: An assessment of specific, geographic, seasonal and multi-decadal variations.

    Science.gov (United States)

    Briant, Nicolas; Savoye, Nicolas; Chouvelon, Tiphaine; David, Valérie; Rodriguez, Samuel; Charlier, Karine; Sonke, Jeroen E; Chiffoleau, Jean François; Brach-Papa, Christophe; Knoery, Joël

    2018-02-01

    Primary consumers play a key role in coastal ecosystems by transferring organic matter from primary producers to predators. Among them, suspension-feeders, like bivalve molluscs are widely used in trophic web studies. The main goal of this study was to investigate variations of C and N elemental and isotopic ratios in common bivalves (M. edulis, M. galloprovincialis, and C. gigas) at large spatial (i.e. among three coastal regions) and different temporal (i.e. from seasonal to multi-decadal) scales in France, in order to identify potential general or specific patterns and speculate on their drivers. The observed spatial variability was related to the trophic status of the coastal regions (oligotrophic Mediterranean Sea versus meso- to eutrophic English Channel and Atlantic ocean), but not to ecosystem typology (estuaries, versus lagoons versus bays versus littoral systems). Furthermore, it highlighted local specificities in terms of the origin of the POM assimilated by bivalves (e.g., mainly continental POM vs. marine phytoplankton vs. microphytobenthic algae). Likewise, seasonal variability was related both to the reproduction cycle for C/N ratios of Mytilus spp. and to changes in trophic resources for δ 13 C of species located close to river mouth. Multi-decadal evolution exhibited shifts and trends for part of the 30-year series with decreases in δ 13 C and δ 15 N. Specifically, shifts appeared in the early 2000's, likely linking bivalve isotopic ratios to a cascade of processes affected by local drivers. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Pteridófitas do Parque Estadual de Vassununga, Santa Rita do Passa Quatro (SP, Brasil. Gleba Pé-de-Gigante. Pteridophytes from Vassununga State Park, Santa Rita do Passa Quatro, SP, Brazil. Gleba Pé-de-Gigante.

    Directory of Open Access Journals (Sweden)

    Áurea Maria Therezinha COLLI

    2004-12-01

    Full Text Available Neste trabalho foi realizado um levantamentode pteridófitas na Gleba Pé-de-Gigante do ParqueEstadual de Vassununga, localizado no municípiode Santa Rita do Passa Quatro, sob as coordenadas21º36’39,01054’’S e 47º37’03,46727’’W. As coletasforam realizadas em três trilhas, denominadasTrilha do Meliponário, Trilha do Córrego Paulicéiae Trilha da Torre. Foram reconhecidas 15 espéciesde pteridófitas pertencentes a 7 famílias. Dessas,as mais representativas foram Polypodiaceae eThelypteridaceae com quatro espécies cada,e Pteridaceae e Schizaeaceae que apresentaramduas espécies cada. Das 15 espécies registradas9 apresentam distribuição bastante restrita, ocorrendoapenas na Trilha do Córrego Paulicéia. Por outrolado, Microgramma squamulosa (Kaulf. de laSota, Pleopeltis angusta Willd e Polypodiumpolypodioides (L. Watt são as espécies deocorrência mais ampla. Em todas as trilhas hápteridófitas, sendo que a Trilha do CórregoPaulicéia é a mais rica, e a Trilha da Torre a maispobre em número de espécies. As pteridófitasocorrem no cerrado “sensu stricto”, cerradão e nafloresta de galeria. A maior diversidade de espéciesfoi encontrada na floresta de galeria.This work presents a pteridophyticalsurvey carried out at the Gleba Pé-de-Gigante ofthe Vassununga State Park, in the municipality ofSanta Rita do Passa Quatro (21º36’39.01054’’Sand 47º37’03.46727’’W. Collections wereaccomplished at three trails called “Trilha doMeliponário, Trilha do Córrego Paulicéia andTrilha da Torre ”. Fifteen species of pteridophytespertaining to 7 families were recognized. From these,the most representative ones were Polypodiaceaeand Thelypteridaceae, with 4 species each, andPteridaceae and Schizaeaceae, with two specieseach. From the 15 species registered, nine present avery restricted distribution occurring only in the“Trilha do Córrego Paulic��ia”, Microgrammasquamulosa, Pleopeltis angusta and

  8. Occurrence of potentially pathogenic Vibrio in oysters (Crassostrea gigas) and waters from bivalve mollusk cultivations in the South Bay of Santa Catarina.

    Science.gov (United States)

    Ramos, Roberta Juliano; Miotto, Letícia Adélia; Miotto, Marília; Silveira Junior, Nelson; Cirolini, Andréia; Silva, Helen Silvestre da; Rodrigues, Dália dos Prazeres; Vieira, Cleide Rosana Werneck

    2014-01-01

    This research aimed to identify and quantify potentially pathogenic Vibrio from different cultivations of bivalve shellfish in the State of Santa Catarina, Brazil, and water regions in the South Bay, as well as correlate the incidence of these microorganisms with the physicochemical parameters of marine waters. Between October 2008 and March 2009, 60 oyster and seawater samples were collected from six regions of bivalve mollusk cultivation, and these samples were submitted for Vibrio counts. Twenty-nine (48.3%) oyster samples were revealed to be contaminated with one or more Vibrio species. The Vibrio parahaemolyticus and Vibrio vulnificus counts in the samples ranged from oyster and from oyster, respectively. Of the 60 seawater samples analyzed, 44 (73.3%) showed signs of contamination with one or more vibrio species. The counts of V. parahaemolyticus and V. vulnificus in the samples ranged from < 0.3 log10 MPN·100mL(-1) to 1.7 log10MPN·100mL(-1) seawater and from < 0.3 log10 MPN·100mL(-1) to 2.0 log10 MPN·100mL(-1) seawater, respectively. A positive correlation between V. vulnificus counts and the seawater temperature as well as a negative correlation between the V. parahaemolyticus counts and salinity were observed. The results suggest the need to implement strategies to prevent vibrio diseases from being transmitted by the consumption of contaminated bivalve shellfish.

  9. PAH assessment in the main Brazilian offshore oil and gas production area using semi-permeable membrane devices (SPMD) and transplanted bivalves

    Science.gov (United States)

    André Lourenço, Rafael; Francisco de Oliveira, Fábio; Haddad Nudi, Adriana; Rebello Wagener, Ângela de Luca; Guadalupe Meniconi, Maria de Fátima; Francioni, Eleine

    2015-06-01

    The Campos Basin is Brazil's main oil and gas production area. In 2013, more than 50 million cubic meters of produced water (PW) was discharged into these offshore waters. Despite the large volumes of PW that are discharged in the Campos Basin each day, the ecological concern of the chemicals in the PW are not completely understood. Polycyclic aromatic hydrocarbons (PAH) are the most important contributors to the ecological hazards that are posed by discharged PW. This study aimed to evaluate the potential bioaccumulation of PAH using transplanted bivalves (Nodipecten nodosus) and semi-permeable membrane devices (SPMD). The study was conducted in two platforms that discharge PW (P19 and P40). Another platform that does not discharge PW (P25) was investigated for comparison with the obtained results. Time-integrated hydrocarbon concentrations using SPMD and transplanted bivalves were estimated from the seawater near the three platforms. The bioaccumulation of the PAH in the transplanted bivalves at platforms P19 and P40 were up to fivefold greater than the bioaccumulation of the PAH at platform P25. The lowest PAH concentrations were estimated for platform P25 (4.3-6.2 ng L-1), and the highest PAH concentrations were estimated for platform P19 (9.2-37.3 ng L-1). Both techniques were effective for determining the bioavailability of the PAH and for providing time-integrated hydrocarbon concentrations regarding oil and gas production activities.

  10. Preliminary Results on the Evaluation of the Occurrence of Tetrodotoxin Associated to Marine Vibrio spp. in Bivalves from the Galician Rias (Northwest of Spain

    Directory of Open Access Journals (Sweden)

    Jose Manuel Leão

    2018-03-01

    Full Text Available Tetrodotoxins (TTX are a potent group of natural neurotoxins putatively produced by symbiotic microorganisms and affecting the aquatic environment. These neurotoxins have been recently found in some species of bivalves and gastropods along the European Coasts (Greece, UK, and The Netherlands linked to the presence of high concentrations of Vibrio, in particular Vibrio parahaemolyticus. This study is focused on the evaluation of the presence of Vibrio species and TTX in bivalves (mussels, oysters, cockles, clams, scallops, and razor clams from Galician Rias (northwest of Spain. The detection and isolation of the major Vibrio spp. and other enterobacterial populations have been carried out with the aim of screening for the presence of the pathways genes, poliketide synthase (PKS and non-ribosomal peptide synthetase (NRPS possibly involved in the biosynthesis of these toxins. Samples containing Vibrio spp. were analyzed by biochemical (API20E-galery and genetic tests (PCR-RT. These samples were then screened for TTX toxicity by a neuroblastoma cell-based assay (N2a and the presence of TTX was further confirmed by LC-MS/MS. TTX was detected in two infaunal samples. This is the first confirmation of the presence of TTX in bivalve molluscs from the Galician Rias.

  11. A critical examination of the possible application of zinc stable isotope ratios in bivalve mollusks and suspended particulate matter to trace zinc pollution in a tropical estuary.

    Science.gov (United States)

    Araújo, Daniel; Machado, Wilson; Weiss, Dominik; Mulholland, Daniel S; Boaventura, Geraldo R; Viers, Jerome; Garnier, Jeremie; Dantas, Elton L; Babinski, Marly

    2017-07-01

    The application of zinc (Zn) isotopes in bivalve tissues to identify zinc sources in estuaries was critically assessed. We determined the zinc isotope composition of mollusks (Crassostrea brasiliana and Perna perna) and suspended particulate matter (SPM) in a tropical estuary (Sepetiba Bay, Brazil) historically impacted by metallurgical activities. The zinc isotope systematics of the SPM was in line with mixing of zinc derived from fluvial material and from metallurgical activities. In contrast, source mixing alone cannot account for the isotope ratios observed in the bivalves, which are significantly lighter in the contaminated metallurgical zone (δ 66 Zn JMC  = +0.49 ± 0.06‰, 2σ, n = 3) compared to sampling locations outside (δ 66 Zn JMC  = +0.83 ± 0.10‰, 2σ, n = 22). This observation suggests that additional factors such as speciation, bioavailability and bioaccumulation pathways (via solution or particulate matter) influence the zinc isotope composition of bivalves. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Effects of depuration on the element concentration in bivalves: Comparison between sympatric Ruditapes decussatus and Ruditapes philippinarum

    Science.gov (United States)

    Freitas, R.; Ramos Pinto, L.; Sampaio, M.; Costa, A.; Silva, M.; Rodrigues, A. M.; Quintino, V.; Figueira, E.

    2012-09-01

    Organisms living in coastal ecosystems are frequently subjected to anthropogenic pressures such as metals. Metals, especially those not required for metabolic activity (e.g. mercury, lead and cadmium) can be toxic even at quite low concentrations not only to organisms that accumulate them, but also to their consumers. Throughout the world, Ruditapes decussatus and Ruditapes philippinarum have been successfully commercialised for human consumption and for monitoring environmental conditions such as contamination. These two clam species share similar habitats and requirements, successfully competing both in the natural environment and in aquaculture farms. Because differences in metal accumulation may exist between R. decussatus and R. philippinarum, different risks to public health may overcome as well as distinct ecological implications. The effect of depuration on the metal burden and biochemical status of both clams species may also diverge and since the information available is subjective and scarce, the aims of the present study were to: 1) assess the total metal accumulation and intracellular partitioning, at natural conditions, in the two clam species collected at the same site; 2) evaluate the effect of depuration as a mean of reducing the levels of distinct elements, assessing also the effect of depuration time (2 and 7 days); 3) investigate the efficiency of depuration by biochemical status of the two bivalve species, evaluating changes in lipid peroxidation and activity of antioxidant enzymes catalase (CAT), superoxide dismutase (SOD) and of glutathione S-transferase (GST). Metal chelation by metallothioneins (MTs) was also determined. The results obtained showed that concentration of elements in clams was low, presenting very similar concentration levels for all elements. The present work further demonstrated that the total element concentration decreased in the shorter depuration period (2 days) and that R. decussatus and R. philippinarum partitioned

  13. Assessing the effects of seawater temperature and pH on the bioaccumulation of emerging chemical contaminants in marine bivalves.

    Science.gov (United States)

    Maulvault, Ana Luísa; Camacho, Carolina; Barbosa, Vera; Alves, Ricardo; Anacleto, Patrícia; Fogaça, Fabiola; Kwadijk, Christiaan; Kotterman, Michiel; Cunha, Sara C; Fernandes, José O; Rasmussen, Rie R; Sloth, Jens J; Aznar-Alemany, Òscar; Eljarrat, Ethel; Barceló, Damià; Marques, António

    2018-02-01

    Emerging chemical contaminants [e.g. toxic metals speciation, flame retardants (FRs) and perfluorinated compounds (PFCs), among others], that have not been historically recognized as pollutants nor their toxicological hazards, are increasingly more present in the marine environment. Furthermore, the effects of environmental conditions (e.g. temperature and pH) on bioaccumulation and elimination mechanisms of these emerging contaminants in marine biota have been poorly studied until now. In this context, the aim of this study was to assess, for the first time, the effect of warmer seawater temperatures (Δ = + 4°C) and lower pH levels (Δ = - 0.4 pH units), acting alone or combined, on the bioaccumulation and elimination of emerging FRs (dechloranes 602, 603 and 604, and TBBPA), inorganic arsenic (iAs), and PFCs (PFOA and PFOS) in two estuarine bivalve species (Mytilus galloprovincialis and Ruditapes philippinarum). Overall, results showed that warming alone or combined with acidification promoted the bioaccumulation of some compounds (i.e. dechloranes 602, 604, TBBPA), but also facilitated the elimination of others (i.e. iAs, TBBPA). Similarly, lower pH also resulted in higher levels of dechloranes, as well as enhanced iAs, PFOA and PFOS elimination. Data also suggests that, when both abiotic stressors are combined, bivalves' capacity to accumulate contaminants may be time-dependent, considering significantly drastic increase observed with Dec 602 and TBBPA, during the last 10 days of exposure, when compared to reference conditions. Such changes in contaminants' bioaccumulation/elimination patterns also suggest a potential increase of human health risks of some compounds, if the climate continues changing as forecasted. Therefore, this first study pointed out the urgent need for further research on the effects of abiotic conditions on emerging contaminants kinetics, to adequately estimate the potential toxicological hazards associated to these compounds and

  14. Source and impact of lead contamination on δ-aminolevulinic acid dehydratase activity in several marine bivalve species along the Gulf of Cadiz

    International Nuclear Information System (INIS)

    Company, R.; Serafim, A.; Lopes, B.; Cravo, A.; Kalman, J.; Riba, I.; DelValls, T.A.; Blasco, J.; Delgado, J.; Sarmiento, A.M.; Nieto, J.M.; Shepherd, T.J.; Nowell, G.; Bebianno, M.J.

    2011-01-01

    Coastal areas and estuaries are particularly sensitive to metal contamination from anthropogenic sources and in the last few decades the study of space-time distribution and variation of metals has been extensively researched. The Gulf of Cadiz is no exception, with several rivers draining one of the largest concentrations of sulphide deposits in the world, the Iberian Pyrite Belt (IPB). Of these rivers, the Guadiana, one of the most important in the Iberian Peninsula, together with smaller rivers like the Tinto and Odiel, delivers a very high metal load to the adjacent coastal areas. The purpose of this work was to study the source and impact of lead (Pb) drained from historical or active mining areas in the IPB on the activity of a Pb inhibited enzyme (δ-aminolevulinic acid dehydratase, ALAD) in several bivalve species along the Gulf of Cadiz. Seven marine species (Chamelea gallina, Mactra corallina, Donax trunculus, Cerastoderma edule, Mytilus galloprovincialis, Scrobicularia plana and Crassostrea angulata) were collected at 12 sites from Mazagon, near the mouth of the rivers Tinto and Odiel (Spain), to Cacela Velha (Ria Formosa lagoon system, Portugal). Lead concentrations, ALAD activity and lead isotope ratios ( 206 Pb/ 204 Pb, 207 Pb/ 204 Pb and 208 Pb/ 204 Pb) were determined in the whole soft tissues. The highest Pb concentrations were determined in S. plana (3.50 ± 1.09 μg g -1 Pb d.w.) and D. trunculus (1.95 ± 0.10 μg g -1 Pb d.w.), while M. galloprovincialis and C. angulata showed the lowest Pb levels ( -1 Pb d.w.). In general, ALAD activity is negatively correlated with total Pb concentration. However this relationship is species dependent (e.g. linear for C. gallina ALAD = -0.36[Pb] + 0.79; r = 0.837; or exponential for M. galloprovincialis ALAD = 2.48e -8.3[Pb] ; r = 0.911). This indicates that ALAD activity has considerable potential as a biomarker of Pb and moreover, in marine bivalve species with different feeding habits. Lead isotope data

  15. NOVOS LETRAMENTOS NA CULTURA DIGITAL: O REMIX VEM PRA RUA - O GIGANTE ACORDOU COMO UM HÍBRIDO

    Directory of Open Access Journals (Sweden)

    Rosivaldo Gomes

    2015-07-01

    Full Text Available A utilização da internet, das mídias e redes sociais digitais e de celulares se constituiu como um diferencial importantíssimo no grande movimento social que mexeu com o País e com as visões sobre ele nas manifestações ocorridas em junho de 2013. Essas mídias e redes sociais digitais (YouTube, Flickr, Facebook, Instagram, Twitter, etc. se constituíram como canais de informação, ambientes comunicacionais, pontos de encontro, enfim, em redes e, às vezes, até em comunidades que facilitaram os relacionamentos entre os que estavam conectados e dispostos a se manifestarem de algum modo. Nessa direção, os novos letramentos digitais e o novo ethos como defendido por Lankshear e Knobel (2007 proporcionaram contribuições significativas para o uso das tecnologias digitais de informação e comunicação na propagação dessas manifestações, e, buscando compreender o modo como esses novos letramentos favoreceram isso, neste artigo buscamos, a partir das noções de hibridismo e intercalação (GARCÍA CANCLINI, 2008 [1989]; BAKHTIN, 2002 [1934-5] e  nas discussões de Lankshear e Knobel (2007; 2008 sobre remix e sobre linguagens hipermidiática e híbrido digital (SANTAELLA, 2003; 2004, realizar uma análise qualitativa do remix digita Vem pra rua - O gigante acordou,  no que diz respeito as técnicas de produção e constituição desse gênero na construção de novos significado, considerando o horizonte espacial e temporal (VOLOCHINOV/BAKHTIN, [1926]1976 nos quais foi produzido

  16. What lies beneath: sub-articular long bone shape scaling in eutherian mammals and saurischian dinosaurs suggests different locomotor adaptations for gigantism.

    Science.gov (United States)

    Bonnan, Matthew F; Wilhite, D Ray; Masters, Simon L; Yates, Adam M; Gardner, Christine K; Aguiar, Adam

    2013-01-01

    Eutherian mammals and saurischian dinosaurs both evolved lineages of huge terrestrial herbivores. Although significantly more saurischian dinosaurs were giants than eutherians, the long bones of both taxa scale similarly and suggest that locomotion was dynamically similar. However, articular cartilage is thin in eutherian mammals but thick in saurischian dinosaurs, differences that could have contributed to, or limited, how frequently gigantism evolved. Therefore, we tested the hypothesis that sub-articular bone, which supports the articular cartilage, changes shape in different ways between terrestrial mammals and dinosaurs with increasing size. Our sample consisted of giant mammal and reptile taxa (i.e., elephants, rhinos, sauropods) plus erect and non-erect outgroups with thin and thick articular cartilage. Our results show that eutherian mammal sub-articular shape becomes narrow with well-defined surface features as size increases. In contrast, this region in saurischian dinosaurs expands and remains gently convex with increasing size. Similar trends were observed in non-erect outgroup taxa (monotremes, alligators), showing that the trends we report are posture-independent. These differences support our hypothesis that sub-articular shape scales differently between eutherian mammals and saurischian dinosaurs. Our results show that articular cartilage thickness and sub-articular shape are correlated. In mammals, joints become ever more congruent and thinner with increasing size, whereas archosaur joints remained both congruent and thick, especially in sauropods. We suggest that gigantism occurs less frequently in mammals, in part, because joints composed of thin articular cartilage can only become so congruent before stress cannot be effectively alleviated. In contrast, frequent gigantism in saurischian dinosaurs may be explained, in part, by joints with thick articular cartilage that can deform across large areas with increasing load.

  17. What lies beneath: sub-articular long bone shape scaling in eutherian mammals and saurischian dinosaurs suggests different locomotor adaptations for gigantism.

    Directory of Open Access Journals (Sweden)

    Matthew F Bonnan

    Full Text Available Eutherian mammals and saurischian dinosaurs both evolved lineages of huge terrestrial herbivores. Although significantly more saurischian dinosaurs were giants than eutherians, the long bones of both taxa scale similarly and suggest that locomotion was dynamically similar. However, articular cartilage is thin in eutherian mammals but thick in saurischian dinosaurs, differences that could have contributed to, or limited, how frequently gigantism evolved. Therefore, we tested the hypothesis that sub-articular bone, which supports the articular cartilage, changes shape in different ways between terrestrial mammals and dinosaurs with increasing size. Our sample consisted of giant mammal and reptile taxa (i.e., elephants, rhinos, sauropods plus erect and non-erect outgroups with thin and thick articular cartilage. Our results show that eutherian mammal sub-articular shape becomes narrow with well-defined surface features as size increases. In contrast, this region in saurischian dinosaurs expands and remains gently convex with increasing size. Similar trends were observed in non-erect outgroup taxa (monotremes, alligators, showing that the trends we report are posture-independent. These differences support our hypothesis that sub-articular shape scales differently between eutherian mammals and saurischian dinosaurs. Our results show that articular cartilage thickness and sub-articular shape are correlated. In mammals, joints become ever more congruent and thinner with increasing size, whereas archosaur joints remained both congruent and thick, especially in sauropods. We suggest that gigantism occurs less frequently in mammals, in part, because joints composed of thin articular cartilage can only become so congruent before stress cannot be effectively alleviated. In contrast, frequent gigantism in saurischian dinosaurs may be explained, in part, by joints with thick articular cartilage that can deform across large areas with increasing load.

  18. In-frame seven amino-acid duplication in AIP arose over the last 3000 years, disrupts protein interaction and stability and is associated with gigantism.

    Science.gov (United States)

    Salvatori, Roberto; Radian, Serban; Diekmann, Yoan; Iacovazzo, Donato; David, Alessia; Gabrovska, Plamena; Grassi, Giorgia; Bussell, Anna-Marie; Stals, Karen; Weber, Astrid; Quinton, Richard; Crowne, Elizabeth C; Corazzini, Valentina; Metherell, Lou; Kearney, Tara; Du Plessis, Daniel; Sinha, Ajay Kumar; Baborie, Atik; Lecoq, Anne-Lise; Chanson, Philippe; Ansorge, Olaf; Ellard, Sian; Trainer, Peter J; Balding, David; Thomas, Mark G; Korbonits, Márta

    2017-09-01

    Mutations in the aryl hydrocarbon receptor-interacting protein ( AIP ) gene are associated with pituitary adenoma, acromegaly and gigantism. Identical alleles in unrelated pedigrees could be inherited from a common ancestor or result from recurrent mutation events. Observational, inferential and experimental study, including: AIP mutation testing; reconstruction of 14 AIP -region (8.3 Mbp) haplotypes; coalescent-based approximate Bayesian estimation of the time to most recent common ancestor (tMRCA) of the derived allele; forward population simulations to estimate current number of allele carriers; proposal of mutation mechanism; protein structure predictions; co-immunoprecipitation and cycloheximide chase experiments. Nine European-origin, unrelated c.805_825dup-positive pedigrees (four familial, five sporadic from the UK, USA and France) included 16 affected (nine gigantism/four acromegaly/two non-functioning pituitary adenoma patients and one prospectively diagnosed acromegaly patient) and nine unaffected carriers. All pedigrees shared a 2.79 Mbp haploblock around AIP with additional haploblocks privately shared between subsets of the pedigrees, indicating the existence of an evolutionarily recent common ancestor, the 'English founder', with an estimated median tMRCA of 47 generations (corresponding to 1175 years) with a confidence interval (9-113 generations, equivalent to 225-2825 years). The mutation occurred in a small tandem repeat region predisposed to slipped strand mispairing. The resulting seven amino-acid duplication disrupts interaction with HSP90 and leads to a marked reduction in protein stability. The c.805_825dup allele, originating from a common ancestor, associates with a severe clinical phenotype and a high frequency of gigantism. The mutation is likely to be the result of slipped strand mispairing and affects protein-protein interactions and AIP protein stability. © 2017 The authors.

  19. Determination of the toxic variability of lipophilic biotoxins in marine bivalve and gastropod tissues treated with an industrial canning process.

    Science.gov (United States)

    García, Carlos; Oyaneder-Terrazas, Javiera; Contreras, Cristóbal; Del Campo, Miguel; Torres, Rafael; Contreras, Héctor R

    2016-11-01

    Contamination of shellfish with lipophilic marine biotoxins (LMB), pectenotoxins (PTXs), yessotoxins (YTXs) and okadaic acid (OA) toxin groups in southern Chile is a constant challenge for the development of miticulture considering the high incidence of toxic episodes that tend to occur. This research is focused on using methodologies for assessing the decrease in toxins of natural resources in Chile with high value, without altering the organoleptic properties of the shellfish. The species were processed through steaming (1 min at 121°C) and subsequent canning (5 min at 121°C). Changes in the profiles of toxins and total toxicity levels of LMB in endemic bivalves and gastropods were determined using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The total reduction of toxicity (≈ 15%) was not related to the destruction of the toxin, but rather to the loss of LMB on removing the shells and packing media of canned products (***p < 0.001). Industrial processing of shellfish reduces LMB contents by up to 15% of the total initial contents, concomitant only with the interconversion of PTX-group toxins into PTX-2sa. In soft bottom-dwelling species with toxicities beyond the standard for safe human consumption (≥ 160 μg OA-eq kg - 1 ), toxicity can be reduced to safe levels through industrial preparation procedures.

  20. Interactive effects of metal contamination and pathogenic organisms on the introduced marine bivalve Ruditapes philippinarum in European populations

    International Nuclear Information System (INIS)

    Paul-Pont, Ika; Montaudouin, Xavier de; Gonzalez, Patrice; Jude, Florence; Raymond, Natalie; Paillard, Christine; Baudrimont, Magalie

    2010-01-01

    In natural environment, marine organisms are concomitantly exposed to pollutants and multiple disease agents resulting in detrimental interactions. The present study evaluated interactive effects of metal contamination (cadmium) and pathogenic organisms (trematode parasites Himasthla elongata and pathogenic bacteria Vibrio tapetis) singularly and in combination on the bivalve Ruditapes philippinarum, an introduced species to Europe, under laboratory controlled conditions. After 7 days, metal bioaccumulation and pathogen load were analyzed as well as metallothionein (MT) response and hemocyte concentrations and activities. Results showed that infection by opportunistic pathogens affects metal accumulation, leading to maximal Cd accumulation in co-infected clams. Among stressors only V. tapetis induced significant effects on immune parameters whereas a particular interaction 'trematode-bacteria' was shown on MT responses. Despite low trematode infection in agreement with the resistant status of R. philippinarum to these macroparasites, significant interaction with bacteria and metal occurred. Such results highlight the necessity of taking pathogens into account in ecotoxicological studies. - Co-infection by opportunistic pathogens affects metal accumulation and some defense-related activities in the Manila clam Ruditapes philippinarum.

  1. Interactive effects of metal contamination and pathogenic organisms on the introduced marine bivalve Ruditapes philippinarum in European populations

    Energy Technology Data Exchange (ETDEWEB)

    Paul-Pont, Ika, E-mail: i.paulpont@epoc.u-bordeaux1.f [Universite Bordeaux 1, UMR 5805 CNRS, Station Marine d' Arcachon, place du Dr. Peyneau, Arcachon 33120 (France); Montaudouin, Xavier de; Gonzalez, Patrice; Jude, Florence; Raymond, Natalie [Universite Bordeaux 1, UMR 5805 CNRS, Station Marine d' Arcachon, place du Dr. Peyneau, Arcachon 33120 (France); Paillard, Christine [Universite de Bretagne Occidentale-IUEM, LEMAR UMR 6539 CNRS, Place Nicolas Copernic, Technopole Brest Iroise, 29280 Plouzane (France); Baudrimont, Magalie [Universite Bordeaux 1, UMR 5805 CNRS, Station Marine d' Arcachon, place du Dr. Peyneau, Arcachon 33120 (France)

    2010-11-15

    In natural environment, marine organisms are concomitantly exposed to pollutants and multiple disease agents resulting in detrimental interactions. The present study evaluated interactive effects of metal contamination (cadmium) and pathogenic organisms (trematode parasites Himasthla elongata and pathogenic bacteria Vibrio tapetis) singularly and in combination on the bivalve Ruditapes philippinarum, an introduced species to Europe, under laboratory controlled conditions. After 7 days, metal bioaccumulation and pathogen load were analyzed as well as metallothionein (MT) response and hemocyte concentrations and activities. Results showed that infection by opportunistic pathogens affects metal accumulation, leading to maximal Cd accumulation in co-infected clams. Among stressors only V. tapetis induced significant effects on immune parameters whereas a particular interaction 'trematode-bacteria' was shown on MT responses. Despite low trematode infection in agreement with the resistant status of R. philippinarum to these macroparasites, significant interaction with bacteria and metal occurred. Such results highlight the necessity of taking pathogens into account in ecotoxicological studies. - Co-infection by opportunistic pathogens affects metal accumulation and some defense-related activities in the Manila clam Ruditapes philippinarum.

  2. Assessment of bioavailability of weathered oil residues using caged bivalves (Crassostrea gigas and Mytilus edulis) as indicator organisms

    International Nuclear Information System (INIS)

    Bleczinski, C.F.; Costa, H.J.; Rigatti, M.J.; Wong, M.C.; Boehm, P.D.

    1993-01-01

    In April 1988, an estimated 400,000 gallons of San Joaquin Valley crude oil spilled into Peyton Slough and subsequently into Suisun Bay from an oil refinery in Martinez, California. The crude oil initially impacted a number of ecologically sensitive environments including estuarine water, marsh grasses, marsh and shoreline sediment, and intertidal sediment. A four-year oil weathering study was performed to determine the concentrations of environmentally important compounds in the stranded oil, to monitor changes in these concentrations over time, and to assess the potential long-term impact of the spilled oil in these various environments. As a result of marked differences in the rate of weathering at the different sites, a bioaccumulation component was added to the original study design in order to assess the bioavailability of crude oil residues remaining four-years post spill. Caged bivalves (Crassostrea gigas and Mytilus edulis) were deployed at the three study sites as sentinel organisms and exposed for three months. Sediments and organism tissues were analyzed using gas chromatography/mass spectrometry for polynuclear aromatic hydrocarbon (PAH) assemblages characteristics of the spilled oil. Advanced hydrocarbon fingerprinting techniques (e.g., double ratio plots of characteristic alkyl PAHs) were used to match distributions in the organisms and in the study site sediments

  3. Laboratory and field assessment of uranium trophic transfer efficiency in the crayfish Orconectes limosus fed the bivalve C. fluminea

    International Nuclear Information System (INIS)

    Simon, Olivier; Garnier-Laplace, Jacqueline

    2005-01-01

    At present, ecotoxicological information regarding the impact of natural uranium (U) on freshwater ecosystems via the trophic contamination route is scarce. We generated an experimental trophic food chain involving the prey species, Corbicula fluminea, and a predator, Orconectes limosus, for a 10-day and a 30-day feeding periods (food ration: one whole soft body/day/crayfish). We studied the efficiency of U trophic transfer and the distribution of U in the predator. During the test, we varied the quantity of dietary U (from beforehand contaminated bivalves at concentrations ranging from 0.9 ± 0.1 to 20.2 ± 9 μg/g fw provided to each crayfish over the 10 days) applying a daily feeding rate equal to 3.9 ± 0.8% fw. The efficiency of U trophic transfer from clams to crayfish varied between 1 and 13% depending on the prey exposure modalities. Accumulation of U was observed in the digestive gland but also in gills, in the muscle, and in the molt of the crayfish after trophic exposure treatments. Under high-level exposure conditions, the digestive gland was the main target-organ, however a significant accumulation was also observed in the stomach. With regard to low levels of trophic exposure, accumulation of U in gills, in the stomach, and in the digestive gland was of the same order of magnitude. Longer exposure period which incorporated a crayfish molt, resulted in a decrease of trophic transfer ratio and a modified U tissue distribution

  4. Feeding behavior of the invasive bivalve Limnoperna fortunei (Dunker, 1857 under exposure to toxic cyanobacteria Microcystis aeruginosa

    Directory of Open Access Journals (Sweden)

    V Gazulha

    Full Text Available The aim of this study was to test the effects of cyanobacteria toxicity on feeding behavior of the golden mussel Limnoperna fortunei. First, it was tested the hypothesis that L. fortunei preferentially graze on non-toxic phytoplankton and reject toxic cyanobacteria. Second, it was tested the hypothesis that toxic cyanobacteria negatively affect feeding and survival of L. fortunei. The present study is the first to evaluate the effects of toxic cyanobacteria on L. fortunei feeding and survival. In the short-term grazing, golden mussel filtration rates were evaluated in the presence of toxic and non-toxic strains of cyanobacteria Microcystis aeruginosa, and non-toxic phytoplankton Nitzschia palea. Highest filtration rates were registered when mussels fed on Nitzschia. Despite that, golden mussel expelled Nitzschia cells in large quantities and preferentially ingested Microcystis cells, both toxic and non-toxic strains. In the long-term grazing, mussels were exposed to toxic and non-toxic strains of Microcystis during 5 days. Filtration rates were not significantly different for toxic and non-toxic Microcystis throughout exposure period. The results have demonstrated cyanobacteria toxicity is not the main factor influencing L. fortunei feeding behavior. Survival of L. fortunei feeding on toxic cyanobacteria shows the potential of this invasive bivalve as a vector to the transference of cyanotoxins to higher trophic levels.

  5. A humidity sensitive two-dimensional tunable amorphous photonic structure in the outer layer of bivalve ligament from Sunset Siliqua

    International Nuclear Information System (INIS)

    Zhang, Weigang; Zhang, Gangsheng

    2015-01-01

    A humidity sensitive two-dimensional tunable amorphous photonic structure (2D TAPS) in the outer layer of bivalve ligament from Sunset Siliqua (OLLS) was reported in this paper. The structural color and microstructure of OLLS were investigated by reflection spectra and scanning electron microscopy, respectively. The results indicate that the reflection peak wavelength of the wet OLLS blue-shifts from 454 nm to 392 nm with the increasing of air drying time from 0 to 40 min, while the reflectivity decreases gradually and vanishes at last, relevant color changes from blue to black background color. The structural color in the OLLS is produced by a two-dimensional amorphous photonic structure consisting of aligned protein fibers, in which the diameter of protein fiber and the inter-fiber spacing are 101 ± 12 nm. Water can reversibly tune the reflection peak wavelength and reflectivity of this photonic structure, and the regulation achieved through dynamically tuning the interaction between inter-fiber spacing and average refractive index. - Highlights: • A humidity sensitive two-dimensional tunable amorphous photonic structure • Water can reversibly tune the reflection peak wavelength and reflectivity of this photonic structure. • This photonic structure may yield very useful template for artificial structures

  6. A humidity sensitive two-dimensional tunable amorphous photonic structure in the outer layer of bivalve ligament from Sunset Siliqua

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Weigang, E-mail: abczwg15@163.com [College of Materials and Chemical Engineering, Chuzhou University, Chuzhou 239000 (China); Zhang, Gangsheng [College of Material Science and Technology, Guangxi University, Nanning 530004 (China)

    2015-07-01

    A humidity sensitive two-dimensional tunable amorphous photonic structure (2D TAPS) in the outer layer of bivalve ligament from Sunset Siliqua (OLLS) was reported in this paper. The structural color and microstructure of OLLS were investigated by reflection spectra and scanning electron microscopy, respectively. The results indicate that the reflection peak wavelength of the wet OLLS blue-shifts from 454 nm to 392 nm with the increasing of air drying time from 0 to 40 min, while the reflectivity decreases gradually and vanishes at last, relevant color changes from blue to black background color. The structural color in the OLLS is produced by a two-dimensional amorphous photonic structure consisting of aligned protein fibers, in which the diameter of protein fiber and the inter-fiber spacing are 101 ± 12 nm. Water can reversibly tune the reflection peak wavelength and reflectivity of this photonic structure, and the regulation achieved through dynamically tuning the interaction between inter-fiber spacing and average refractive index. - Highlights: • A humidity sensitive two-dimensional tunable amorphous photonic structure • Water can reversibly tune the reflection peak wavelength and reflectivity of this photonic structure. • This photonic structure may yield very useful template for artificial structures.

  7. Borniopsis mortoni sp. n. (Heterodonta, Galeommatoidea, Galeommatidae sensu lato, a new bivalve commensal with a synaptid sea cucumber from Japan

    Directory of Open Access Journals (Sweden)

    Ryutaro Goto

    2016-09-01

    Full Text Available The Galeommatoidea is a bivalve superfamily that exhibits high species diversity in shallow waters. Many members of this superfamily are associated commensally with burrowing marine invertebrates in benthic sediments. The genus Borniopsis is known only from eastern Asia and exhibits high host diversity (e.g., mantis shrimps, crabs, holothurians, sipunculans and echiurans. A new species, Borniopsis mortoni sp. n., is described from mud flats at the mouth of the Souzu River, southwestern Shikoku Island, Japan. This species has elongate-ovate shells covered by a tan to dark brown periostracum, and lives attached by both its foot and byssal threads to the body surface of the synaptid sea cucumber Patinapta ooplax. Several individuals of B. mortoni are often found on the same host, but sometimes more than 10 individuals can occur together. Borniopsis mortoni is one of the smallest species in this genus. Probably, its small body size is an adaptation to the mode of life in a narrow host burrow. Until now, only two other Borniopsis species were known to have commensal associations with synaptids. Thus, this is the third example of a synaptid-associated species from this genus. In addition, we briefly review the galeommatoideans commensal with apodid sea cucumbers.

  8. Latitudinal variation in the reproductive cycle of two bivalves with contrasting biogeographical origin along the Humboldt Current Upwelling Ecosystem

    Directory of Open Access Journals (Sweden)

    Roberto A. Uribe

    2012-10-01

    Full Text Available Argopecten purpuratus (Lamarck, 1819 and Mesodesma donacium (Lamarck, 1818 are bivalves that inhabit the Humboldt Current Upwelling Ecosystem. They have contrasting biogeographical origins, suggesting that their responses to exogenous factors should differ. Using circular statistics, we examine synchrony/asynchrony in the reproductive cycle between populations of each species. The results indicate that there is reproductive asynchrony in both species along their distributional range. However, there was synchrony for A. purpuratus in several location-pairs, including Paita-Chimbote, Chimbote-Callao, Callao-Pisco and Pisco-Antofagasta. For M. donacium, there were only two synchronic groups: Camaná-Capellanía-Mehuín and Hornitos-Peñuelas-Longotoma-La Ligua-Cucao-Quilanlar. A. purpuratus showed gametogenenic activity throughout the year. In contrast, M. donacium showed strong seasonality, with gametogenesis in winter and spawning in spring/summer. In conclusion, the patterns observed for these sympatric species suggest that on a large scale the reproductive cycles follow the expected patterns for the contrasting biogeographic origin of each species, so it could be argued that they are modulated by endogenous factors. However, at a local scale, the reproductive cycles of these species show variation, likely determined by local oceanographic or hydrographic processes.

  9. Genotoxic and Cytotoxic Effects on the Immune Cells of the Freshwater Bivalve Dreissena polymorpha Exposed to the Environmental Neurotoxin BMAA.

    Science.gov (United States)

    Lepoutre, Alexandra; Milliote, Nadia; Bonnard, Marc; Palos-Ladeiro, Mélissa; Rioult, Damien; Bonnard, Isabelle; Bastien, Fanny; Faassen, Elisabeth; Geffard, Alain; Lance, Emilie

    2018-03-01

    The environmental neurotoxin β- N -Methylamino-l-alanine (BMAA) has been pointed out to be involved in human neurodegenerative diseases. This molecule is known to be bioaccumulated by bivalves. However, little data about its toxic effects on freshwater mussels is available, particularly on the hemolymphatic compartment and its hemocyte cells involved in various physiological processes such as immune defenses, digestion and excretion, tissue repair, and shell production. Here we exposed Dreissena polymorpha to dissolved BMAA, at the environmental concentration of 7.5 µg of /mussel/3 days, during 21 days followed by 14 days of depuration in clear water, with the objective of assessing the BMAA presence in the hemolymphatic compartment, as well as the impact of the hemocyte cells in terms of potential cytotoxicity, immunotoxicity, and genotoxiciy. Data showed that hemocytes were in contact with BMAA. The presence of BMAA in hemolymph did not induce significant effect on hemocytes phagocytosis activity. However, significant DNA damage on hemocytes occurred during the first week (days 3 and 8) of BMAA exposure, followed by an increase of hemocyte mortality after 2 weeks of exposure. Those effects might be an indirect consequence of the BMAA-induced oxidative stress in cells. However, DNA strand breaks and mortality did not persist during the entire exposure, despite the BMAA persistence in the hemolymph, suggesting potential induction of some DNA-repair mechanisms.

  10. A complete Holocene record of trematode-bivalve infection and implications for the response of parasitism to climate change.

    Science.gov (United States)

    Huntley, John Warren; Fürsich, Franz T; Alberti, Matthias; Hethke, Manja; Liu, Chunlian

    2014-12-23

    Increasing global temperature and sea-level rise have led to concern about expansions in the distribution and prevalence of complex-lifecycle parasites (CLPs). Indeed, numerous environmental variables can influence the infectivity and reproductive output of many pathogens. Digenean trematodes are CLPs with intermediate invertebrate and definitive vertebrate hosts. Global warming and sea level rise may affect these hosts to varying degrees, and the effect of increasing temperature on parasite prevalence has proven to be nonlinear and difficult to predict. Projecting the response of parasites to anthropogenic climate change is vital for human health, and a longer term perspective (10(4) y) offered by the subfossil record is necessary to complement the experimental and historical approaches of shorter temporal duration (10(-1) to 10(3) y). We demonstrate, using a high-resolution 9,600-y record of trematode parasite traces in bivalve hosts from the Holocene Pearl River Delta, that prevalence was significantly higher during the earliest stages of sea level rise, significantly lower during the maximum transgression, and statistically indistinguishable in the other stages of sea-level rise and delta progradation. This stratigraphic paleobiological pattern represents the only long-term high-resolution record of pathogen response to global change, is consistent with fossil and recent data from other marine basins, and is instructive regarding the future of disease. We predict an increase in trematode prevalence concurrent with anthropogenic warming and marine transgression, with negative implications for estuarine macrobenthos, marine fisheries, and human health.

  11. Prevalence of human pathogenic enteric viruses in bivalve molluscan shellfish and cultured shrimp in south west coast of India.

    Science.gov (United States)

    Umesha, Kanasinakatte R; Bhavani, Naniah C; Venugopal, Moleyur N; Karunasagar, Indrani; Krohne, Georg; Karunasagar, Iddya

    2008-03-20

    The prevalence of human enteric viruses in bivalve molluscan shellfish and shrimp collected off the south west coast of India was studied to assess the extent of fecal pollution of coastal environment. Out of 194 samples analyzed, 37% of oyster, 46% of clam and 15% of shrimp samples were positive for enteroviruses (EV). Adenoviruses (ADV) were detected in 17% of oyster and 27% of clam samples. However, other enteric viruses such as noroviruses (NoV) and hepatitis A virus (HAV) were not detected in any of the samples. High prevalence of EV and ADV was noticed between May to December. Thirty four percent of oyster and 49% of clam samples showed fecal coliform values higher than the limit. MS-2 phage was detected in 57% of oyster and 73% of clam samples. The presence of MS-2 phage and human enteric viruses showed association while fecal coliforms and enteric viruses showed no association. However, 17 samples, which were positive for enteric viruses (EV and ADV), were negative for MS-2 phage.

  12. Bathymetric and geographic population structure in the pan-Atlantic deep-sea bivalve Deminucula atacellana (Schenck, 1939).

    Science.gov (United States)

    Zardus, John D; Etter, Ron J; Chase, Michael R; Rex, Michael A; Boyle, Elizabeth E

    2006-03-01

    The deep-sea soft-sediment environment hosts a diverse and highly endemic fauna of uncertain origin. We know little about how this fauna evolved because geographic patterns of genetic variation, the essential information for inferring patterns of population differentiation and speciation are poorly understood. Using formalin-fixed specimens from archival collections, we quantify patterns of genetic variation in the protobranch bivalve Deminucula atacellana, a species widespread throughout the Atlantic Ocean at bathyal and abyssal depths. Samples were taken from 18 localities in the North American, West European and Argentine basins. A hypervariable region of mitochondrial 16S rDNA was amplified by polymerase chain reaction (PCR) and sequenced from 130 individuals revealing 21 haplotypes. Except for several important exceptions, haplotypes are unique to each basin. Overall gene diversity is high (h = 0.73) with pronounced population structure (Phi(ST) = 0.877) and highly significant geographic associations (P < 0.0001). Sequences cluster into four major clades corresponding to differences in geography and depth. Genetic divergence was much greater among populations at different depths within the same basin, than among those at similar depths but separated by thousands of kilometres. Isolation by distance probably explains much of the interbasin variation. Depth-related divergence may reflect historical patterns of colonization or strong environmental selective gradients. Broadly distributed deep-sea organisms can possess highly genetically divergent populations, despite the lack of any morphological divergence.

  13. Complete sequences of the highly rearranged molluscan mitochondrial genomes of the scaphopod graptacme eborea and the bivalve mytilus edulis

    Energy Technology Data Exchange (ETDEWEB)

    Boore, Jeffrey L.; Medina, Monica; Rosenberg, Lewis A.

    2004-01-31

    We have determined the complete sequence of the mitochondrial genome of the scaphopod mollusk Graptacme eborea (Conrad, 1846) (14,492 nts) and completed the sequence of the mitochondrial genome of the bivalve mollusk Mytilus edulis Linnaeus, 1758 (16,740 nts). (The name Graptacme eborea is a revision of the species formerly known as Dentalium eboreum.) G. eborea mtDNA contains the 37 genes that are typically found and has the genes divided about evenly between the two strands, but M. edulis contains an extra trnM and is missing atp8, and has all genes on the same strand. Each has a highly rearranged gene order relative to each other and to all other studied mtDNAs. G. eborea mtDNA has almost no strand skew, but the coding strand of M. edulis mtDNA is very rich in G and T. This is reflected in differential codon usage patterns and even in amino acid compositions. G. eborea mtDNA has fewer non-coding nucleotides than any other mtDNA studied to date, with the largest non-coding region being only 24 nt long. Phylogenetic analysis using 2,420 aligned amino acid positions of concatenated proteins weakly supports an association of the scaphopod with gastropods to the exclusion of Bivalvia, Cephalopoda, and Polyplacophora, but is generally unable to convincingly resolve the relationships among major groups of the Lophotrochozoa, in contrast to the good resolution seen for several other major metazoan groups.

  14. Covarying Shell Growth Parameters and the Regulation of Shell Shape in Marine Bivalves: A Case Study on Tellinoidea

    Directory of Open Access Journals (Sweden)

    Jean Béguinot

    2014-01-01

    Full Text Available Specific parameters characterising shell shape may arguably have a significant role in the adaptation of bivalve molluscs to their particular environments. Yet, such functionally relevant shape parameters (shell outline elongation, dissymmetry, and ventral convexity are not those parameters that the animal may directly control. Rather than shell shape, the animal regulates shell growth. Accordingly, an alternative, growth-based description of shell-shape is best fitted to understand how the animal may control the achieved shell shape. The key point is, in practice, to bring out the link between those two alternative modes of shell-shape descriptions, that is, to derive the set of equations which connects the growth-based shell-shape parameters to the functionally relevant shell-shape parameters. Thus, a preliminary object of this note is to derive this set of equations as a tool for further investigations. A second object of this work is to provide an illustrative example of implementation of this tool. I report on an unexpected negative covariance between growth-based parameters and show how this covariance results in a severe limitation of the range of interspecific variability of the degree of ventral convexity of the shell outline within the superfamily Tellinoidea. Hypotheses are proposed regarding the constraints possibly at the origin of this limitation of interspecific variability.

  15. Factors influencing the microplastic contamination of bivalves from the French Atlantic coast: Location, season and/or mode of life?

    Science.gov (United States)

    Phuong, Nam Ngoc; Poirier, Laurence; Pham, Quoc Tuan; Lagarde, Fabienne; Zalouk-Vergnoux, Aurore

    2018-04-01

    Monitoring the presence of microplastics (MP) in marine organisms is currently of high importance. This paper presents the qualitative and quantitative MP contamination of two bivalves from the French Atlantic coasts: the blue mussel (Mytilus edulis) and the Pacific oyster (Crassostrea gigas). Three factors potentially influencing the contamination were investigated by collecting at different sampling sites and different seasons, organisms both wild and cultivated. Inter- and intra-species comparisons were also achieved. MP quantity in organisms was evaluated at 0.61±0.56 and 2.1±1.7MP per individual respectively for mussels and oysters. Eight different polymers were identified. Most of the MPs were fragments; about a half of MPs were grey colored and a half with a size ranging from 50 to 100μm for both studied species. Some inter-specific differences were found but no evidence for sampling site, season or mode of life effect was highlighted. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Genotoxic and Cytotoxic Effects on the Immune Cells of the Freshwater Bivalve Dreissena polymorpha Exposed to the Environmental Neurotoxin BMAA

    Directory of Open Access Journals (Sweden)

    Alexandra Lepoutre

    2018-03-01

    Full Text Available The environmental neurotoxin β-N-Methylamino-l-alanine (BMAA has been pointed out to be involved in human neurodegenerative diseases. This molecule is known to be bioaccumulated by bivalves. However, little data about its toxic effects on freshwater mussels is available, particularly on the hemolymphatic compartment and its hemocyte cells involved in various physiological processes such as immune defenses, digestion and excretion, tissue repair, and shell production. Here we exposed Dreissena polymorpha to dissolved BMAA, at the environmental concentration of 7.5 µg of /mussel/3 days, during 21 days followed by 14 days of depuration in clear water, with the objective of assessing the BMAA presence in the hemolymphatic compartment, as well as the impact of the hemocyte cells in terms of potential cytotoxicity, immunotoxicity, and genotoxiciy. Data showed that hemocytes were in contact with BMAA. The presence of BMAA in hemolymph did not induce significant effect on hemocytes phagocytosis activity. However, significant DNA damage on hemocytes occurred during the first week (days 3 and 8 of BMAA exposure, followed by an increase of hemocyte mortality after 2 weeks of exposure. Those effects might be an indirect consequence of the BMAA-induced oxidative stress in cells. However, DNA strand breaks and mortality did not persist during the entire exposure, despite the BMAA persistence in the hemolymph, suggesting potential induction of some DNA-repair mechanisms.

  17. Microbial Communities in Sunken Wood Are Structured by Wood-Boring Bivalves and Location in a Submarine Canyon

    Science.gov (United States)

    Fagervold, Sonja K.; Romano, Chiara; Kalenitchenko, Dimitri; Borowski, Christian; Nunes-Jorge, Amandine; Martin, Daniel; Galand, Pierre E.

    2014-01-01

    The cornerstones of sunken wood ecosystems are microorganisms involved in cellulose degradation. These can either be free-living microorganisms in the wood matrix or symbiotic bacteria associated with wood-boring bivalves such as emblematic species of Xylophaga, the most common deep-sea woodborer. Here we use experimentally submerged pine wood, placed in and outside the Mediterranean submarine Blanes Canyon, to compare the microbial communities on the wood, in fecal pellets of Xylophaga spp. and associated with the gills of these animals. Analyses based on tag pyrosequencing of the 16S rRNA bacterial gene showed that sunken wood contained three distinct microbial communities. Wood and pellet communities were different from each other suggesting that Xylophaga spp. create new microbial niches by excreting fecal pellets into their burrows. In turn, gills of Xylophaga spp. contain potential bacterial symbionts, as illustrated by the presence of sequences closely related to symbiotic bacteria found in other wood eating marine invertebrates. Finally, we found that sunken wood communities inside the canyon were different and more diverse than the ones outside the canyon. This finding extends to the microbial world the view that submarine canyons are sites of diverse marine life. PMID:24805961

  18. Astrocitoma subependimario de células gigantes asociado a complejo de esclerosis tuberosa: recomendaciones para el diagnóstico oportuno y tratamiento.

    OpenAIRE

    Matilde Ruiz; Sandra Sánchez; Alejandro Rea; Roberto Sanromán; Joao García; Antonio Bravo; Infante Cantú; Hugo Ceja; Ariadna González; María del Mar Sáez

    2015-01-01

    RESUMEN El complejo de esclerosis tuberosa es una enfermedad genética poco frecuente, autosómica dominante con fenotipo y expresión clínica muy variables. Se caracteriza por alteraciones en la migración, diferenciación y proliferación celulares con formación de múltiples tumores benignos llamados hamartomas, las cuales afectan principalmente piel, encéfalo, riñón, ojo, corazón y pulmón. Los astrocitomas subependimarios de células gigantes son tumores benignos de crecimien...

  19. Florística em um hectare de cerrado stricto sensu na ARIE - cerrado Pé-de-Gigante, Santa Rita do Passa Quatro, SP

    OpenAIRE

    Weiser, Veridiana de Lara; Godoy, Silvana Aparecida Pires de

    2001-01-01

    Foi realizado um levantamento florístico em um ha de cerrado stricto sensu, na parte norte da ARIE - Cerrado Pé-de-Gigante, Santa Rita do Passa Quatro, São Paulo. Foram coletados 428 espécimes em fase reprodutiva, em vinte e cinco excursões de coleta, durante o período de novembro de 1996 a abril de 1998. A listagem florística obtida apresenta 141 espécies, distribuídas em 109 gêneros e 49 famílias. As famílias mais representativas foram: Leguminosae, Asteraceae, Malpighiaceae e Myrtaceae. A ...

  20. 'Gigantic' increase of AFMR frequencies induced by nonmagnetic impurity ions in orthoferrites RFe1-xAlxO3 (R=Gd,Tb)

    International Nuclear Information System (INIS)

    Mukhin, A.A.; Parsegov, I.Yu.

    1996-01-01

    We observed a 'gigantic' increase (up to three times) of the AFMR frequencies ν 1,2 with decreasing temperature in GdFe 0.9 Al 0.1 O 3 and TbFe 0.925 Al 0.075 O 3 in contrast to pure GdFeO 3 and TbFeO 3 . The effects observed are explained by the appearance of an additional exchange field H mv ∼20 -36 kOe on rare-earth ions due to decompensation of the surrounding antiferromagnetically ordered Fe ions near nonmagnetic impurity ions. (orig.)