Effect-based analysis of endocrine activity in sediment samples from lakes in Taihu Basin, China

Lactotrophs, as many other endocrine cells, change their morphology in response to factors influencing their secretory activity. Secretion of prolactin (PRL) from lactotrophs, like that of other anterior pituitary hormones, is under the control of the hypothalamus. Unlike most anterior pituitary hormones, PRL has no apparent target gland which could modulate the endocrine activity of lactotrophs. It is generally agreed that PRL regulates its own release from lactotrophs via the short loop negative feedback mechanism exerted at the level of the hypothalamus or the pituitary. Accordingly, ultrastructural morphology of lactotrophs is not constant; it is changing in response to high PRL levels showing signs of suppressed hormone synthesis and secretion.By transmission electron microscopy and morphometry, we have studied the morphology of lactotrophs in nontumorous (NT) portions of 7 human pituitaries containing PRL-secreting adenoma; these lactotrophs were exposed to abnormally high PRL levels.

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Holocene diatom assemblages from Dunderbukhta sediments, West Svalbard

Issues of modern algology (Вопросы современной альгологии) ◽

10.33624/2311-0147-2019-2(20)-242-245 ◽

2019 ◽

pp. 242-245

Author(s):

Ksenya V. Poleshchuk ◽

Zinaida V. Pushina ◽

Sergey R. Verkulich

Keyword(s):

Environmental Changes ◽

Ecological Groups ◽

Diatom Assemblages ◽

Diatom Analysis ◽

Diatom Flora ◽

Sediment Samples ◽

Ecological Zones ◽

Middle Holocene ◽

Temperature Trends

The diatom analysis results of sediment samples from Dunderbukta area (Wedel Jarlsberg Land, West Svalbard) are presented in this paper. The diatom flora consists of four ecological groups, which ratio indicates three ecological zones. These zones show environmental changes of the area in early–middle Holocene that is demonstrating periods of regression and temperature trends.

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ENDOCRINE ACTIVITY OF THE HUMAN FALLOPIAN TUBE

Acta Endocrinologica ◽

10.1530/acta.0.061s080 ◽

1969 ◽

Vol 61 (1_Suppl) ◽

pp. S80 ◽

Cited By ~ 2

Author(s):

Hubertus A. van Leusden

Keyword(s):

Fallopian Tube ◽

Endocrine Activity ◽

Human Fallopian Tube

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ANALYSIS OF ACCUMULATION AND DISTRIBUTION OF LEAD IN THE SYSTEM WATER-BOTTOM SEDIMENTS IN THE BACH DANG ESTUARY (VIETNAM)

VESTNIK OF ASTRAKHAN STATE TECHNICAL UNIVERSITY SERIES FISHING INDUSTRY ◽

10.24143/2073-5529-2017-1-62-66 ◽

2017 ◽

pp. 62-66

Author(s):

Truong Van Tuan ◽

Irina Vladimirovna Volkova

Keyword(s):

Bottom Sediment ◽

Bottom Sediments ◽

Water Samples ◽

Suspended Solids ◽

Natural Habitat ◽

Bottom Layer ◽

Sediment Samples ◽

Natural Breeding ◽

System Water ◽

Water Bottom

Research was held in the estuary of the river Bach Dang (Dongbay community, Rakhtay district, Hai Phong, Vietnam) in June, 2012 - May, 2013. Concentration of lead was studied in water, suspended solids and bottom sediment. Clam beach (natural breeding environment of Meretrix lyrata ) was inspected regularly, every month. Water samples were taken 6 times from the bottom layer 10 cm down the bottom, once per 3 hours in each of 12 investigated zones. Bottom sediment samples were taken at the depth 2 cm. The findings show that lead accumulates mainly in suspended solids (23.3 mg/kg) and in bottom sediment (14.31 mg/kg), in water it is in small quantities (0.003 mg/kg). Analysis of bottom sediment samples taken in different places showed that they have even leadcontent, lead is distributed uniformly, localization of contaminations is not found. The results obtained can be assumed as the basis for investigating lead accumulation and its excretion by clam Meretrix lyrata organisms in the natural habitat.

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