28 research outputs found
Expression pattern of arenicins—the antimicrobial peptides of polychaete Arenicola marina
Immune responses of invertebrate animals are mediated through innate mechanisms, among which production of antimicrobial peptides play an important role. Although evolutionary Polychaetes represent an interesting group closely related to a putative common ancestor of other coelomates, their immune mechanisms still remain scarcely investigated. Previously our group has identified arenicins - new antimicrobial peptides of the lugworm Arenicola marina, since then these peptides were thoroughly characterized in terms of their structure and inhibitory potential. In the present study we addressed the question of the physiological functions of arenicins in the lugworm body. Using molecular and immunocytochemical methods we demonstrated that arencins are expressed in the wide range of the lugworm tissues - coelomocytes, body wall, extravasal tissue and the gut. The expression of arenicins is constitutive and does not depend on stimulation of various infectious stimuli. Most intensively arenicins are produced by mature coelomocytes where they function as killing agents inside the phagolysosome. In the gut and the body wall epithelia arenicins are released from producing cells via secretion as they are found both inside the epithelial cells and in the contents of the cuticle. Collectively our study showed that arenicins are found in different body compartments responsible for providing a first line of defence against infections, which implies their important role as key components of both epithelial and systemic branches of host defence
A Rat Model of Post-Traumatic Stress Syndrome Causes Phenotype-Associated Morphological Changes and Hypofunction of the Adrenal Gland
Background: Rats exposed to chronic predator scent stress mimic the phenotype of complex
post-traumatic stress disorder (PTSD) in humans, including altered adrenal morphology and function.
High- and low-anxiety phenotypes have been described in rats exposed to predator scent stress
(PSS). This study aimed to determine whether these high- and low-anxiety phenotypes correlate with
changes in adrenal histomorphology and corticosteroid production. Methods: Rats were exposed
to PSS for ten days. Thirty days later, the rats’ anxiety index (AI) was assessed with an elevated
plus-maze test. Based on differences in AI, the rats were segregated into low- (AI ≤ 0.8, n = 9)
and high- (AI > 0.8, n = 10) anxiety phenotypes. Plasma corticosterone (CORT) concentrations
were measured by ELISA. Adrenal CORT, desoxyCORT, and 11-dehydroCORT were measured
by high-performance liquid chromatography. After staining with hematoxylin and eosin, adrenal
histomorphometric changes were evaluated by measuring the thickness of the functional zones of the
adrenal cortex. Results: Decreased plasma CORT concentrations, as well as decreased adrenal CORT,
desoxyCORT and 11-dehydroCORT concentrations, were observed in high- but not in low-anxietyphenotypes. These decreases were associated with increases in AI. PSS led to a significant decrease in
the thickness of the zona fasciculata and an increase in the thickness of the zona intermedia. The increase
in the thickness of the zona intermedia was more pronounced in low-anxiety than in high-anxiety
rats. A decrease in the adrenal capsule thickness was observed only in low-anxiety rats. The nucleus
diameter of cells in the zona fasciculata of high-anxiety rats was significantly smaller than that of
control or low-anxiety rats. Conclusion: Phenotype-associated changes in adrenal function and
histomorphology were observed in a rat model of complex post-traumatic stress disorder
A Rat Model of Post-Traumatic Stress Syndrome Causes Phenotype-Associated Morphological Changes and Hypofunction of the Adrenal Gland
BACKGROUND
Rats exposed to chronic predator scent stress mimic the phenotype of complex post-traumatic stress disorder (PTSD) in humans, including altered adrenal morphology and function. High- and low-anxiety phenotypes have been described in rats exposed to predator scent stress (PSS). This study aimed to determine whether these high- and low-anxiety phenotypes correlate with changes in adrenal histomorphology and corticosteroid production.
METHODS
Rats were exposed to PSS for ten days. Thirty days later, the rats' anxiety index (AI) was assessed with an elevated plus-maze test. Based on differences in AI, the rats were segregated into low- (AI ≤ 0.8, n = 9) and high- (AI > 0.8, n = 10) anxiety phenotypes. Plasma corticosterone (CORT) concentrations were measured by ELISA. Adrenal CORT, desoxyCORT, and 11-dehydroCORT were measured by high-performance liquid chromatography. After staining with hematoxylin and eosin, adrenal histomorphometric changes were evaluated by measuring the thickness of the functional zones of the adrenal cortex.
RESULTS
Decreased plasma CORT concentrations, as well as decreased adrenal CORT, desoxyCORT and 11-dehydroCORT concentrations, were observed in high- but not in low-anxiety phenotypes. These decreases were associated with increases in AI. PSS led to a significant decrease in the thickness of the zona fasciculata and an increase in the thickness of the zona intermedia. The increase in the thickness of the zona intermedia was more pronounced in low-anxiety than in high-anxiety rats. A decrease in the adrenal capsule thickness was observed only in low-anxiety rats. The nucleus diameter of cells in the zona fasciculata of high-anxiety rats was significantly smaller than that of control or low-anxiety rats.
CONCLUSION
Phenotype-associated changes in adrenal function and histomorphology were observed in a rat model of complex post-traumatic stress disorder
Development of a new technology of environmental purification from naphthalene
Results of investigation of naphthalene interaction with humic acids of high-moor peat and their fractions are presented in the article. The elemental and structural-group compositions of humic acids of high-moor peat and of their fractions are determined, average values of their molecular masses are found, and their spectral and luminescent properties are investigated. Numerical values of constants of naphthalene interaction with humic acids and their fractions are calculated, and the polarity of naphthalene microenvironment in solutions of humic acids is estimated. The results of investigations suggest that the maximum affinity of naphthalene is observed to the fraction of hematomelanic acids and that the naphthalene microenvironment in solutions of the given fraction is polar
Development of a new technology of environmental purification from naphthalene
Results of investigation of naphthalene interaction with humic acids of high-moor peat and their fractions are presented in the article. The elemental and structural-group compositions of humic acids of high-moor peat and of their fractions are determined, average values of their molecular masses are found, and their spectral and luminescent properties are investigated. Numerical values of constants of naphthalene interaction with humic acids and their fractions are calculated, and the polarity of naphthalene microenvironment in solutions of humic acids is estimated. The results of investigations suggest that the maximum affinity of naphthalene is observed to the fraction of hematomelanic acids and that the naphthalene microenvironment in solutions of the given fraction is polar
Development of a New Technology of Environmental Purification from Naphthalene
Results of investigation of naphthalene interaction with humic acids of high-moor peat and their fractions are presented in the article. The elemental and structural-group compositions of humic acids of high-moor peat and of their fractions are determined, average values of their molecular masses are found, and their spectral and luminescent properties are investigated. Numerical values of constants of naphthalene interaction with humic acids and their fractions are calculated, and the polarity of naphthalene microenvironment in solutions of humic acids is estimated. The results of investigations suggest that the maximum affinity of naphthalene is observed to the fraction of hematomelanic acids and that the naphthalene microenvironment in solutions of the given fraction is polar