Causes of zonal distribution of glycogen in the liver acinus after a fat-rich diet

1973 ◽  
Vol 29 (5) ◽  
pp. 545-546 ◽  
Author(s):  
W. den Otter ◽  
L. F. Blikkendaal-Lieftinck ◽  
J. W. Koten
Keyword(s):  
Zonal Distribution ◽  
Liver Acinus

scholarly journals Quantitative histochemical analysis of glucose-6-phosphatase activity in rat liver using an optimized cerium-diaminobenzidine method.

1990 ◽  
Vol 38 (10) ◽  
pp. 1413-1419 ◽  
Author(s):  
G N Jonges ◽  
C J Van Noorden ◽  
R Gossrau
Keyword(s):  
Oxidative Polymerization ◽  
Male Rats ◽  
Functional Difference ◽  
Histochemical Analysis ◽  
Zonal Distribution ◽  
Cerium Phosphate ◽  
Liver Acinus ◽  
G6pase Activity ◽  
Km Value ◽  
Cytophotometric Analysis

We have optimized a cerium-diaminobenzidine-based method for histochemical analysis of glucose-6-phosphatase (G6Pase) activity and have determined quantitative data on the zonal distribution pattern in the liver acinus of fasted male rats. In the cerium-diaminobenzidine technique, cerium instead of lead ions is used as capturing reagent for the enzymatically liberated phosphate. For light microscopy, the primary reaction product, cerium phosphate, is then visualized by conversion into cerium perhydroxide using hydrogen peroxide and subsequent oxidative polymerization of diaminobenzidine to diaminobenzidine brown as the final reaction product. Variation of the substrate (glucose-6-phosphate) concentration in the incubation medium yielded in periportal zones a KM value of 2.3 +/- 0.7 mM and a Vmax value of 0.96 +/- 0.18 (expressed as mean integrated absorbance). In perivenous zones a KM value of 1.1 +/- 0.4 mM and a Vmax value of 0.51 +/- 0.08 were calculated. The cytophotometric analysis performed in this study demonstrated for the first time that a functional difference of G6Pase, the key enzyme for gluconeogenesis, exists in the periportal and perivenous zones of the liver acinus. Periportal zones contain twice as many enzyme molecules (high Vmax) as perivenous zones, but the affinity for the substrate is twice as low. This may have important implications for the concept of metabolic zonation of the liver and also for glucose homeostasis in the blood.

Assessment of copper accumulation in archived liver specimens from cats

2020 ◽  
pp. 1098612X2096135
Author(s):  
Punyamanee Yamkate ◽  
Randi M Gold ◽  
Panagiotis G Xenoulis ◽  
Katja Steiger ◽  
David C Twedt ◽  
...  
Keyword(s):  
Infectious Disease ◽  
Hepatic Steatosis ◽  
Dry Weight ◽  
Reference Interval ◽  
Copper Accumulation ◽  
Zonal Distribution ◽  
Tissue Samples ◽  
Hepatic Copper ◽  
Liver Copper ◽  
Flame Atomic Absorption

Objectives The aim of this study was to assess hepatic copper concentrations and zonal distribution in cat liver specimens. Methods For this study, 121 archived, formalin-fixed, paraffin-embedded liver specimens from cats were used. Tissue sections were stained for copper with rhodanine and scored from 0 (no copper accumulation) to 5 (panlobular copper accumulation). The tissue specimens were then deparaffinized and hepatic copper concentrations were measured using flame atomic absorption spectroscopy. Results Tissue samples were categorized into four groups based on histopathologic findings: (1) no significant histopathologic hepatic changes (n = 66); (2) hepatic steatosis (n = 18); (3) inflammatory or infectious disease (n = 24); and (4) neoplasia (n = 13). Of the 121 specimens, 13 (11%) stained positive for copper, with three having a score ⩾3. Thirty-seven specimens (31%) had copper concentrations above the reference interval ([RI] <180 µg/g dry weight liver). Copper concentrations in cats with hepatic inflammatory or infectious disease were significantly higher than cats with hepatic steatosis ( P = 0.03). Copper-staining score and concentration were positively correlated ( rs = 0.46, P <0.001). Conclusions and relevance Despite the fact that 31% of specimens had copper concentrations above the RI, only 11% showed positive copper staining and only 2.5% had a score ⩾3. Our findings suggest that hepatic copper concentrations greater than the upper limit of the RI are relatively common in cats. Further studies to determine the factors that influence hepatic copper staining in cats and to establish contemporary RIs for hepatic copper in healthy cats are warranted.

scholarly journals The features of the coastal fronts in the Eastern Guangdong coastal waters during the downwelling-favorable wind period

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Chaoyu Yang ◽  
Haibin Ye
Keyword(s):  
Coastal Waters ◽  
Meteorological Data ◽  
Pearson Correlation ◽  
Ocean Model ◽  
Ekman Pumping ◽  
Zonal Distribution ◽  
Factors Affecting ◽  
China Sea ◽  
Hybrid Coordinate Ocean Model ◽  
The Mean

AbstractA coastal front was detected in the eastern Guangdong (EGD) coastal waters during a downwelling-favorable wind period by using the diffuse attenuation coefficient at 490 nm (Kd(490)). Long-term satellite data, meteorological data and hydrographic data collected from 2003 to 2017 were jointly utilized to analyze the environmental factors affecting coastal fronts. The intensities of the coastal fronts were found to be associated with the downwelling intensity. The monthly mean Kd(490) anomalies in shallow coastal waters less than 25 m deep along the EGD coast and the monthly mean Ekman pumping velocities retrieved by the ERA5 dataset were negatively correlated, with a Pearson correlation of − 0.71. The fronts started in October, became weaker and gradually disappeared after January, extending southwestward from the southeastern coast of Guangdong Province to the Wanshan Archipelago in the South China Sea (SCS). The cross-frontal differences in the mean Kd(490) values could reach 3.7 m−1. Noticeable peaks were found in the meridional distribution of the mean Kd(490) values at 22.5°N and 22.2°N and in the zonal distribution of the mean Kd(490) values at 114.7°E and 114.4°E. The peaks tended to narrow as the latitude increased. The average coastal surface currents obtained from the global Hybrid Coordinate Ocean Model (HYCOM) showed that waters with high nutrient and sediment contents in the Fujian and Zhejiang coastal areas in the southern part of the East China Sea could flow into the SCS. The directions and lengths of the fronts were found to be associated with the flow advection.

Preparation of Iron Carbide from High Phosphorus Oolitic Hematite

2014 ◽  
Vol 881-883 ◽  
pp. 98-101
Author(s):  
Guang Qiang Li ◽  
Heng Hui Wang ◽  
Jian Yang ◽  
Jiang Hua Ma
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Iron Carbide ◽  
Xrd Analysis ◽  
Raw Material ◽  
Zonal Distribution ◽  
High Phosphorus ◽  
Hematite Ore ◽  
Oolitic Hematite Ore ◽  
Scanning Electron

In order to find a new way to utilize the high phosphorus oolitic hematite ore as raw material for steelmaking, the reduction and carburization of high phosphorus oolitic hematite by the gas of CH4-H2were studied. High phosphorus oolitic hematite, reduction and carburization products were investigated by the means of XRD and scanning electron microscope. The SEM-EDS and XRD analysis show that the main compositions of this ore are hematite and quartz, main microstructure is oolitic cluster with the zonal distribution of hematite and apatite, and iron carbide can be prepared from high phosphorus oolitic hematite.

scholarly journals Vegetative structure and zonal distribution of true mangroves in Shwe-Thaung-Yan coastal areas, Myanmar

2021 ◽  
Vol 10 (1) ◽  
pp. 33-39
Author(s):  
Soe- Win
Keyword(s):  
Environmental Parameters ◽  
Iucn Red List ◽  
Coastal Areas ◽  
Red List ◽  
Mangrove Forests ◽  
Zonation Pattern ◽  
Zonal Distribution ◽  
Rhizophora Apiculata ◽  
Bruguiera Gymnorhiza ◽  
Point Center

The survey was conducted in the mangrove forests around the Magyi and Utto Creeks at Shwe-Thaung-Yan coastal areas in Ayeyarwady Delta region, April 2018. Transect lines were laid as lower, middle and upper, and quadrate plots based on Point Center Quarter Method (PCQM) P-DATA PRO were used. A total of 15 species of true mangrove was recorded. Rhizophora apiculata and Bruguiera gymnorhiza are the most dominant and distributed species in the study area. Followed by Bruguiera sexangulata, Cerop tagal and Rhizophora mucronata then remaining species. Zonation pattern of mangroves species as lower, middle, upper was also examined in study areas. Among than 1 species in Near Threaten (NT), 1 species in Critically Endangered (CR), 1 species in Endangered (EN) and remaining species are Least Concern (LC) had been considered according with IUCN red list. The environmental parameters such as water salinity and temperature, soil salinity, soil temperature and soil pH of study area were also recorded.

scholarly journals Features of biotopic differentiation of ecomorphs spectra of amphibiotic insects (Insecta: Ephemeroptera, Plecoptera, Odonata) communities in hydroecosystems of Ukrainian Carpathians

2019 ◽  
pp. 59-66
Author(s):  
K. Hushtan
Keyword(s):  
Spatial Distribution ◽  
Dominant Species ◽  
Trophic Groups ◽  
River Continuum ◽  
Zonal Distribution ◽  
Number Of Species ◽  
Amphibiotic Insects

The peculiarities of biotope differentiation of amphibiotic insects ecomorphs spectra (Insecta: Ephemeroptera, Plecoptera, Odonata) in hydroecosystems of Ukrainian Carpathians are established. Among Ephemeroptera ecomorphs, the dominant species (in the number of species) were: subclass ploskotili velykoziabrovi zbyrachi-ziskobliuvachi ta khyzhaky; subclass siflonuroidni dribno ziabrovi zbyrachi-ziskobliuvachi. For epirytral, the dominant ecomorphs among the freckles are kryptobionty shchilyn briofily (35%); for metarytral – fitofilni kryptobionty podribniuvachi (61%); litofilni kryptobionty, yaki poliuiut iz zasidky (71%) – predominate in hiporytral. The spatial distribution of ecomorph groups of mayflies and stoneflies in Ukrainian Carpathians is subject to the general tendencies of vertical zonal distribution of trophic groups of zoobenthos, and is consistent with the basic provisions of the theory of river continuum of R. Vannot.

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