scholarly journals Comparative analysis of two methodological approaches to the study of endocrine disruptor alpha-cypermethrin reproductive toxicity

2021 ◽  
Vol 12 (4) ◽  
pp. 724-732
Author(s):  
N. R. Shepelska ◽  
M. G. Prodanchuk ◽  
Y. V. Kolianchuk

At present, one of the main threats to humanity is undoubtedly endocrine disruptors (ED), since they directly disrupt the processes of ensuring homeostasis, which are identical to the very essence of the concept of health, considered in valeology as the ability to maintain age-appropriate stability in conditions of sharp changes in quantitative and qualitative parameters of the triune flow of sensory, verbal and structural information. Pesticides can disrupt the physiological functioning of many endocrine chains, including the endocrine mechanisms that ensure reproductive health. The study aimed to compare the results of our studies of alpha-cypermethrin reproductive toxicity in the test system for studying gonadotoxic activity with data obtained in the test system "Three Generation Reproduction Study". The studies were performed on male and female Wistar Han rats with two generic samples of alpha-cypermethrin from different manufacturers at doses of 0.2, 1.0 and 3.0 mg/kg body weight. The exposure lasted 11 (males) and 10 (females) weeks. During the last two weeks of exposure the state of the estrous cycle, duration and frequency of each stage in females was studied. After the end of treatment functional parameters of the state of the gonads in males and the ability of animals to reproduce were examined. In males, the total sperm count, the absolute and relative number of motile germ cells, and the number of pathologically altered forms were evaluated. The results of the study showed that exposure of male and female Wistar Han rats to alpha-cypermethrin at doses of 0.2–3.0 mg/kg during gametogenesis had a toxic effect on the reproductive system characterized by impaired gonadal and reproductive functions. In our studies, alpha-cypermethrin was found to have reproductive toxicity (reduced number of corpora luteum and live fetuses, increased absolute and relative postimplantation death, reduced average weight of fetuses and litters) and endocrine-disruptive effect, having a pronounced antiandrogenic effect on males. Obvious signs of endocrine reproductive disorders (changes in testis and epididymis weight, deterioration in semen parameters, altered length of separate stages of the estrous cycle) were observed in both females and males. However, studies in a test system of three-generations did not reveal a reproductive and endocrine-disruptive effect of cypermethrin, the toxicity of which was recognized as equivalent to the toxicity of alpha-cypermethrin. The obtained results showed higher sensitivity, informative and diagnostic significance of the methods for studying gonadotoxicity than the methodology of reproductive toxicity studies in the test system “Three Generation Reproduction Study”.


2021 ◽  
Vol 54 (1) ◽  
pp. 52-61
Author(s):  
NR Shepelskaya ◽  
YaV Kolyanchuk

Aim. Studying the effect of generic pesticides cyproconazole (98 %) and two samples of epoxiconazole (epoxiconazole 1 — 95,75 % and epoxiconazole 2 — 98,7 %) on the reproductive system of male and female Wistar Han rats at the level of the organism when exposed during gametogenesis, identification and characterization of their hazard, as well as assessment of the risk of reproductive toxicity of these compounds. Materials and Methods. The test samples were administered daily (5 days a week) by oral gavage at doses of 0.2 and 2.0 mg/kg for cyproconazole and 0.5 and 2.0 mg/kg for epoxiconazoles during 11 weeks for males, and 10 weeks for females. Also, there were kept intact males and females, intended for crossover mating with experimental animals. After the end of the exposure, functional indicators of the state of the gonads and the ability of animals to reproduce offspring were studied. The duration and the frequency of each stage of the estrous cycle in female rats and the number of motile sperm, the total amount of sperm and the number of abnormal forms of germ cells of the male rats were studied. The reproductive function state in females was evaluated on day 20th of pregnancy. Thereby the number of corpora lutea in the ovaries, number of alive, dead and resorbed foetuses and embryos, the foetus weight, total weight of litters were registered. The studies were carried out in accordance with the recommendations of the Bioethics Commission and the Centre’s standard operating procedures, developed in accordance with the recommendations and requirements of Good Laboratory Practice (GLP). Conclusions. Test substances at a maximum dose of 2.0 mg/kg of body weight have reproductive toxicity and endocrine-disruptive effect, exerting a significant antiandrogenic effect on males and antiestrogenic effect on female rats. No-observed-adverse-effect-level (NOАEL) for gonadal and reproductive toxicity for male and female Wistar Han rats were established. They are 0.2 mg/kg body weight for cyproconazole and 0.5 mg/kg body weight for epoxiconazole. Key Words: azole fungicides, cyproconazole, epoxiconazole, reproductive toxicity, antiandrogenic and antiestrogenic effects, Wistar Han rats.



2019 ◽  
Vol 84 (4) ◽  
pp. 36-41
Author(s):  
Ya.V. Kolianchyk

Objective. Identification of hazard and assessment of the risk of gonado- and reproductive toxicity of two generic pesticides of technical-grade carbendazim of different purity bin male and female Wistar Han rats. Materials and Methods. Carbendazim with the purity of 98 % (C1) and 98.1 % (C2) was intragastrically administered on the daily basis, excluding Saturday and Sunday, at the doses of 2.5 and 25 mg/kg body weight in three groups of animals (20 males and female rats in each) during 10 weeks (forfemales) and 11 weeks (for males). Control animals received an equivalent amount of the solvent. Intact animals intended for breeding were managed in parallel with the control and experimental animals. After the end of the exposure, functional parameters of the condition of gonads and reproductive ability of the animals were investigated. Females were used to investigate the condition of the oestral cycle, duration and frequency of each stage of it. The condition of the reproductive function in the female rats was considered at Day 20 of pregnancy. Indices of breeding, conception, fertility, pregnancy were established, and the duration of the pre-coitalperiod was considered. Results and Discussion. The data obtained suggest that exposure to two generic substances of carbendazim at the dose of 25 mg/kg body weight during 11 weeks is manifested in general toxic effect (body weight reduction) only in males upon exposure to C2. All test substances in the maximum dose have reproductive toxicity and show significant anti-androgenic action that is manifested as changes in the morphological and functional parameters of the condition of gonads in the experimental groups of male rats. Furthermore, the negative effect on the oestral cycle in experimental female rats exposed to C2 was noted. Conclusion. Based on the obtained results it can be concluded that all test samples of carbendazim have reproductive toxicity at the dose of 25 mg/kg body weight. No-observed-effect level (NOEL) for all test compounds is 2.5 mg/kg body weight. Dose-effect dependence was observed in the range of studies doses.



Energies ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2301
Author(s):  
Yun-Sung Cho ◽  
Yun-Hyuk Choi

This paper describes a methodology for implementing the state estimation and enhancing the accuracy in large-scale power systems that partially depend on variable renewable energy resources. To determine the actual states of electricity grids, including those of wind and solar power systems, the proposed state estimation method adopts a fast-decoupled weighted least square approach based on the architecture of application common database. Renewable energy modeling is considered on the basis of the point of data acquisition, the type of renewable energy, and the voltage level of the bus-connected renewable energy. Moreover, the proposed algorithm performs accurate bad data processing using inner and outer functions. The inner function is applied to the largest normalized residue method to process the bad data detection, identification and adjustment. While the outer function is analyzed whether the identified bad measurements exceed the condition of Kirchhoff’s current law. In addition, to decrease the topology and measurement errors associated with transformers, a connectivity model is proposed for transformers that use switching devices, and a transformer error processing technique is proposed using a simple heuristic method. To verify the performance of the proposed methodology, we performed comprehensive tests based on a modified IEEE 18-bus test system and a large-scale power system that utilizes renewable energy.



1903 ◽  
Vol 35 (7) ◽  
pp. 188-188 ◽  
Author(s):  
W. E. Britton

Crioceris12-punctata, Linn, is an introduced species, and has been working northward from Maryland, according to Professor J.B. Smith, who some time ago informed me that it was present in New Jersey, and would in time reach Connecticut. The first speciment recorded from the State was taken by a student assistant June, 16th, 1902, who collected a single speciment on asparagus upon the Station grounds in New Haven. On May 23rd, 1903, I took male and female specimens from the same locality. We may now expect this species to become thoroughly established here as a pest of asparagus, beetle, C. asparagi, Linn.



Zootaxa ◽  
2004 ◽  
Vol 523 (1) ◽  
pp. 1 ◽  
Author(s):  
SERGIO IBÁÑEZ-BERNAL

Only three species of Trichomyia Haliday have been recorded in Mexico. Trichomyia cirrata Coquillett, 1902, is recognized by its female characteristics, T. fairchildi Vargas and D az-N jera, 1953, was described based only on the wing and must be considered as species inquirenda, and T. maldonadoi (Vargas, 1953), which was described based on one female specimen. Specimens of Trichomyia collected in the states of Campeche, Yucatan, and Oaxaca, Mexico, allowed this female to be associated with the male of T. brevitarsa (Rapp, 1945), thus providing a first report of this species in Mexico. Consequently, T. maldonadoi is proposed as a synonym of T. brevitarsa. Additionally, a new species of Trichomyia from the state of Veracruz, Mexico, is described and illustrated based on the male and female characteristics.



1976 ◽  
Vol 20 (2) ◽  
pp. 97-109 ◽  
Author(s):  
L. Jesel ◽  
Cl. Aron


2011 ◽  
Vol 5 (5) ◽  
pp. 282-292 ◽  
Author(s):  
Irene A. Fawzy ◽  
Nashwa N. Kamal ◽  
Ahlam M. Abdulla


2016 ◽  
Vol 48 (2) ◽  
pp. 89 ◽  
Author(s):  
Vasily V. Grebennikov

This paper reports discovery of the genus <em>Disphaerona</em> Jordan, 1902 in two widely separated regions in China: in three isolated highlands in Yunnan (the Cang Shan Range, Mt. Jizu and Mt. Haba) and in the Dabie Mountains of Hubei, at the border with Anhui. Till present the genus was known from China only from four specimens of<em> D.</em> <em>chinensis</em> (including its holotype) described from Sichuan in 1995. Sixteen specimens from each of the three newly detected localities in Yunnan were DNA barcoded and the data were made publicly available at dx.doi.org/10.5883/DS-DISPHAE. Temporal phylogenetic analysis revealed a topology suggesting monophyly and recent (0.2–0.4 Ma) origin of the populations on both Mt. Jizu and Mt. Haba. The population on the Cang Shan Range harbours representatives of both clades forming the ingroup, mtDNA of which diverged some 7.9 Ma. The habitus of the holotype of the only nominative Chinese <em>Disphaerona</em> species, <em>D. chinensis,</em> is illustrated, together with habitus and male and female genitalia of specimens newly discovered in both Yunnan and Hubei. All specimens of <em>Disphaerona</em> from Yunnan are seemingly conspecific and are taxonomically assigned to D. chinensis. Two similar males and one sympatric but dissimilar, smaller female from the Dabie Mountains do not have associated DNA barcode data. It remains unknown whether the three Dabie Mountains specimens are conspecific or even congeneric; pending this uncertainty they are tentatively treated as <em>Disphaerona</em> without a Linnaean name. <em>Disphaerona</em> population in the Dabie Mountains, if indeed a member of this hypothesised clade, forms the easternmost record of the genus. Monophyly and sister group of <em>Disphaerona</em> are briefly discussed and both are shown as unknown and unverifiable. A brief overview of the state of phylogenetic knowledge of Anthribidae is given, which is practically non-existing and with neither the family, nor any of its tribes and the vast majority of genera tested as monophyletic.



1998 ◽  
Vol 10 (2) ◽  
pp. 179 ◽  
Author(s):  
M. H. Al-Hamood ◽  
A. Elbetieha ◽  
H. Bataineh

The reproductive toxicity of trivalent and hexavalent chromium compounds was investigated in male and female mice exposed to 1000 ppm chromium chloride and potassium dichromate via their mother during gestational and lactational periods. Fertility was reduced in male offspring exposed to either trivalent or hexavalent chromium compounds. Body weights and weights of testes, seminal vesicles and preputial glands were reduced in trivalent-exposed male offspring. The exposure of female mice offspring to trivalent and hexavalent chromium compounds delayed sexual maturation. Fertility was reduced in female offspring exposed to either trivalent or hexavalent chromium compounds. The exposure of female mice to hexavalent chromium compound reduced the number of implantations and viable fetuses respectively. Body weight and weights of ovaries and uteri were reduced in trivalent-exposed female offspring. The results indicate that under our experimental conditions, the exposure of male and female mice offspring to either trivalent or hexavalent chromium compounds during gestational and lactational periods impair reproductive functions and fertility in adulthood.



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