Effects of season and of manipulation of circulating prolactin concentrations on deiodinase activity in cashmere goat skin

2004 ◽  
Vol 55 (2) ◽  
pp. 211 ◽  
Author(s):  
S. M. Rhind ◽  
C. E. Kyle ◽  
E. I. Duff

The effects of season and of manipulations of circulating prolactin concentrations on the expression of monodeiodinase type II (MDII) and monodeiodinase type III (MDIII) expression in the skin of cashmere goats were investigated. Deiodinase enzymes control the rates of synthesis and degradation of triiodothyronine (T3), a hormone implicated in the control of hair follicle activity, and so changes in expression with season or prolactin profiles may affect cashmere fibre growth and moult. There was a very high degree of variation between animals in expression of each enzyme. There was also evidence of seasonal variation in expression within individuals, with a trend towards lower levels of activity of MDII during periods of long daylength (July and April) and highest levels in December, whereas levels of MDIII were highest in July and lowest in December. Collectively, these differences with season resulted in significant changes with date in the MDIII/MDII ratio. It is concluded that the seasonal changes in deiodinase activity, and in particular in the MDIII/MDII ratio, may have an important role in the regulation of follicle activity. Levels of MD activity were poorly correlated with circulating hormone profiles. Nevertheless, since manipulation of the circulating concentrations of prolactin induced additional changes in MDIII/MDII ratios, which were associated with treatment differences in follicle activity or moult, it is concluded that seasonal changes in prolactin may determine patterns of enzyme activity, with high concentrations of prolactin being associated with reduced net levels of T3 synthesis.

2004 ◽  
Vol 55 (4) ◽  
pp. 443 ◽  
Author(s):  
S. M. Rhind ◽  
C. E. Kyle

The roles of skin deiodinase enzymes in the expression of genotypic differences in hair follicle activity and cashmere fibre growth and moult were studied in 9 Siberian (S) and 10 Scottish cashmere (SC) goats. The proportion of animals exhibiting cashmere growth was significantly greater in S than in SC goats in both late July (P < 0.001; early in the season of growth) and between January and April (P < 0.001; late in the season of growth), but there was no significant difference in the time of moult onset. Patterns of hair follicle activity exhibited similar seasonal differences, with secondary follicle activity being higher in S than in SC animals during the January–June period. Overall mean concentrations of IGF-I were lower (P < 0.01) in S than in SC animals and mean T4 concentrations were higher (P < 0.05) in S than in SC animals, but these differences were not related to genotypic differences in follicle activity or cashmere fibre growth. Mean concentrations of insulin, prolactin, and T3 did not differ with genotype. Between January and early April, mean prolactin concentrations were higher in S than in SC animals (P < 0.05). Monodeiodinase type II (MDII) activity in skin samples was highest (P < 0.001) during December and January (short day photoperiod) and was lower in S than in SC animals (P < 0.05) at these times. Mean monodeiodinase type III (MDIII) activity was highest during June and July (long day photoperiod). There was no difference between genotypes in the overall mean levels of deiodinase activity but, during January–March, when prolactin concentrations were higher in S than in SC goats, there was a higher rate of follicle activity and fibre growth in S goats. It is postulated that individual and genotype differences in hair follicle activity and cashmere growth are partially dependent on the pattern of expression of deiodinase enzymes in the skin. However, the actions of each enzyme are likely to depend on, among other factors, the absolute levels of expression of each type, the ratio of MDIII to MDII, the physiological state of the follicle, and the associated hormone profiles.


Author(s):  
Cecil E. Hall

The visualization of organic macromolecules such as proteins, nucleic acids, viruses and virus components has reached its high degree of effectiveness owing to refinements and reliability of instruments and to the invention of methods for enhancing the structure of these materials within the electron image. The latter techniques have been most important because what can be seen depends upon the molecular and atomic character of the object as modified which is rarely evident in the pristine material. Structure may thus be displayed by the arts of positive and negative staining, shadow casting, replication and other techniques. Enhancement of contrast, which delineates bounds of isolated macromolecules has been effected progressively over the years as illustrated in Figs. 1, 2, 3 and 4 by these methods. We now look to the future wondering what other visions are waiting to be seen. The instrument designers will need to exact from the arts of fabrication the performance that theory has prescribed as well as methods for phase and interference contrast with explorations of the potentialities of very high and very low voltages. Chemistry must play an increasingly important part in future progress by providing specific stain molecules of high visibility, substrates of vanishing “noise” level and means for preservation of molecular structures that usually exist in a solvated condition.


2011 ◽  
Vol E94-C (10) ◽  
pp. 1548-1556 ◽  
Author(s):  
Takana KAHO ◽  
Yo YAMAGUCHI ◽  
Kazuhiro UEHARA ◽  
Kiyomichi ARAKI

1984 ◽  
Vol 49 (5) ◽  
pp. 1061-1078 ◽  
Author(s):  
Jiří Čeleda ◽  
Stanislav Škramovský

Based on the earlier paper introducing a concept of the apparent parachor of a solute in the solution, we have eliminated in the present work algebraically the effect which is introduced into this quantity by the additivity of the apparent molal volumes. The difference remaining from the apparent parachor after substracting the contribution corresponding to the apparent volume ( for which the present authors suggest the name metachor) was evaluated from the experimental values of the surface tension of aqueous solutions for a set of 1,1-, 1,2- and 2,1-valent electrolytes. This difference showed to be independent of concentration up to the very high values of the order of units mol dm-3 but it was directly proportional to the number of the free charges (with a proportionality factor 5 ± 1 cm3 mol-1 identical for all studied electrolytes). The metachor can be, for this reason, a suitable characteristic for detection of the association of ions and formation of complexes in the solutions of electrolytes, up to high concentrations where other methods are failing.


Water ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1607
Author(s):  
Mariano Venturini ◽  
Ariana Rossen ◽  
Patricia Silva Paulo

To produce nuclear fuels, it is necessary to convert uranium′s ore into UO2-ceramic grade, using several quantities of kerosene, methanol, nitric acid, ammonia, and, in low level, tributyl phosphate (TBP). Thus, the effluent generated by nuclear industries is one of the most toxic since it contains high concentrations of dangerous compounds. This paper explores biological parameters on real nuclear wastewater by the Monod model in an ORP controlled predicting the specific ammonia oxidation. Thermodynamic parameters were established using the Nernst equation to monitor Oxiders/Reductors relationship to obtain a correlation of these parameters to controlling and monitoring; that would allow technical operators to have better control of the nitrification process. The real nuclear effluent is formed by a mixture of two different lines of discharges, one composed of a high load of nitrogen, around 11,000 mg/L (N-NH4+-N-NO3−) and 600 mg/L Uranium, a second one, proceeds from uranium purification, containing TBP and COD that have to be removed. Bioprocesses were operated on real wastewater samples over 120 days under controlled ORP, as described by Nernst equations, which proved to be a robust tool to operate nitrification for larger periods with a very high load of nitrogen, uranium, and COD.


Author(s):  
Mario Vincenzo Russo ◽  
Ivan Notardonato ◽  
Alberto Rosada ◽  
Giuseppe Ianiri ◽  
Pasquale Avino

This paper shows a characterization of the organic and inorganic fraction of river waters (Tiber and Marta) and ores/soil samples collected in the Northern Latium region of Italy for evaluating the anthropogenic/natural source contribution to the environmental pollution of this area. For organic compounds, organochloride volatile compounds in Tiber and Marta rivers were analyzed by two different clean-up methods (i.e., liquid–liquid extraction and static headspace) followed by gas chromatography–electron capture detector (GC-ECD) analysis. The results show very high concentrations of bromoform (up to 1.82 and 3.2 µg L−1 in Tiber and Marta rivers, respectively), due to the presence of greenhouse crops, and of chloroform and tetrachloroethene, due to the presence of handicrafts installations. For the qualitative and quantitative assessment of the inorganic fraction, it is highlighted the use of a nuclear analytical method, instrumental neutron activation analysis, which allows having more information as possible from the sample without performing any chemical-physical pretreatment. The results have evidenced high levels of mercury (mean value 88.6 µg g−1), antimony (77.7 µg g−1), strontium (12,039 µg g−1) and zinc (103 µg g−1), whereas rare earth elements show levels similar to the literature data. Particular consideration is drawn for arsenic (414 µg g−1): the levels found in this paper (ranging between 1 and 5100 µg g−1) explain the high content of such element (as arsenates) in the aquifer, a big issue in this area.


Genetics ◽  
1996 ◽  
Vol 144 (2) ◽  
pp. 635-645 ◽  
Author(s):  
David A Kirby ◽  
Wolfgang Stephan

Abstract We surveyed sequence variation and divergence for the entire 5972-bp transcriptional unit of the white gene in 15 lines of Drosophila melanogaster and one line of D. simulans. We found a very high degree of haplotypic structuring for the polymorphisms in the 3′ half of the gene, as opposed to the polymorphisms in the 5′ half. To determine the evolutionary mechanisms responsible for this pattern, we sequenced a 1612-bp segment of the white gene from an additional 33 lines of D. melanogaster from a European and a North American population. This 1612-bp segment encompasses an 834bp region of the white gene in which the polymorphisms form high frequency haplotypes that cannot be explained by a neutral equilibrium model of molecular evolution. The small number of recombinants in the 834bp region suggests epistatic selection as the cause of the haplotypic structuring, while an investigation of nucleotide diversity supports a directional selection hypothesis. A multi-locus selection model that combines features from both-hypotheses and takes the recent history of D. melanogaster into account may be the best explanation for these data.


2021 ◽  
pp. 101426
Author(s):  
Shelby L. Francis ◽  
Jacob E. Simmering ◽  
Linnea A. Polgreen ◽  
Nicholas J. Evans ◽  
Katie R. Hosteng ◽  
...  

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Kayeen Vadakkan ◽  
Meena K Cheruvathur ◽  
Anu S Chulliparambil ◽  
Famy Francis ◽  
Anu P Abimannue

Abstract Background There have been several studies carried out to irradiate Helminthiasis however very little research have been carried out where in the enzymatic activity of plants are exploited to antagonize infections. Here we are analyzing the anthelmintic activity of Cinnamomum cappara leaf extract against Pheretima posthuma complimented by proteolytic action. Results The fresh leaves of Cinnamomum cappara was collected from local areas of Thrissur during December 2019. Plants were identified and authenticated by morphological and molecular characterization. The enzymatic action was analyzed by plotting Lineweaver–Burk plot which suggested that the extract possess the Km 185.77 μM for casein as substrate and obeyed Michaelis–Menten kinetics with typical hyperbolic relation with enzyme and increasing concentration of substrate. The effect of extract upon study subject was in directly proportional with concentration of antagonist where higher activities were obtained in high concentrations. The anatomical and histological studies suggested that the activity of extract was due to the degradation of muscular bundle of subject that resulted in the leakage of ceolomic fluid. Conclusions Cinnamomum cappara leaf extract possessed high degree of protease intervened anthelmintic activity against Pheretima posthuma. As the study subject show immense morphological and physiological resemblance with all other helminthic parasites, this results shall be adopted to further clinical and pharmacological applications.


1960 ◽  
Vol 38 (1) ◽  
pp. 25-32 ◽  
Author(s):  
Ivan T. Beck ◽  
E. Pinter ◽  
R. D. McKenna ◽  
H. Griff

Acute hemorrhagic pancreatitis in humans is thought to be perpetuated by the autolytic processes catalyzed by trypsin and lipase. This study is an integral part of our search for trypsin and lipase inhibitors to be used in the treatment of this disease.Benzethonium chloride was found to inhibit tryptic activity in vitro. The proteolytic activity of rabbit's serum was inhibited, and the inhibition was most pronounced 6 to 12 hours after the subcutaneous injection of the compound. Fibrinolysin was also inhibited in vitro but benzethonium chloride had no inhibitory action on chymotrypsin, pepsin, or lipase.Serum proteins in vitro were precipitated only with very high concentrations of the compound. No significant protein changes were observed in sera of rabbits after the subcutaneous injection of the compound.


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