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Author(s):  
Lilian de Paula Gonçalves Reis ◽  
Antonio Jesús Lora-Benítez ◽  
Ana Mª Molina-López ◽  
Rafael Mora-Medina ◽  
Nahúm Ayala-Soldado ◽  
...  

Bisphenol A (BPA) is a chemical substance commonly used in the manufacture of plastic products. Its inhalation or ingestion from particles in suspension, water, and/or polluted foods can trigger toxic effects related to endocrine disruption, resulting in hormonal, reproduction, and immunological alterations in humans and animals. The zebrafish (Danio rerio) is an ideal experimental model frequently used in toxicity studies. In order to assess the toxic effects of BPA on reproduction and embryonic development in one generation after parental exposure to it, a total of 80 zebrafish, males and females, divided into four groups in duplicate (n = 20) were exposed to BPA concentrations of 500, 50, and 5 µg L−1, along with a control group. The fish were kept in reproduction aquariums for 21 days. The embryos obtained in the crosses were incubated in a BPA-free medium and observed for signs of embryotoxicity. A histopathological study (under optical and electron microscopes) was performed of adult fish gonads. The embryos of reproducers exposed to BPA were those most frequently presenting signs of embryotoxicity, such as mortality and cardiac and musculoskeletal malformations. In the histopathological studies of adult individuals, alterations were found in ovocyte maturation and in spermatazoid formation in the groups exposed to the chemical. Those alterations were directly related to BPA action, affecting fertility in both sexes, as well as the viability of their offspring, proportionally to the BPA levels to which they were exposed, so that our results provide more information by associating toxic effects on the offspring and on the next generation.


2022 ◽  
pp. 1-11
Author(s):  
Bo Wang ◽  
Zhuoshu Li ◽  
Longfei Mao ◽  
Mingyi Zhao ◽  
Bingchang Yang ◽  
...  

<b><i>Background:</i></b> Hydrogen is a chemical substance that has yet to be widely used in medicine. However, recent evidence indicates that hydrogen has multi-faceted pharmacological effects such as antioxidant, anti-inflammatory, and antiapoptotic properties. An increased number of studies are being conducted on the application of hydrogen in various diseases, especially those affecting the renal system. <b><i>Summary:</i></b> Hydrogen can be inhaled, as a gas or liquid, and can be administered orally, intravenously, or locally. Hydrogen can rapidly enter suborganelles such as mitochondria and nucleus by simple diffusion, producing reactive oxygen species (ROS) and triggering DNA damage. Hydrogen can selectively scavenge hydroxyl radical (•OH) and peroxynitrite (ONOO<sup>−</sup>), but not other reactive oxygen radicals with physiological functions, such as peroxyanion (O<sub>2</sub><sup>−</sup>) and hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>). Although the regulatory effect of hydrogen on the signal transduction pathway has been confirmed, the specific mechanism of its influence on signal molecules remains unknown. Although many studies have investigated the therapeutic and preventive effects of H<sub>2</sub> in cellular and animal experiments, clinical trials are few and still far behind. As a result, more clinical trials are required to investigate the role of hydrogen in kidney disease, as well as the effect of its dose, timing, and form on the overall efficacy. Large-scale randomized controlled clinical trials will be required before hydrogen can be used to treat renal illnesses. <b><i>Key Messages:</i></b> This article reviews the mechanisms of hydrogen in the treatment of renal disease and explores the possibilities of its use in clinical practice.


Complexity ◽  
2022 ◽  
Vol 2022 ◽  
pp. 1-13
Author(s):  
Lili Gu ◽  
Shamaila Yousaf ◽  
Akhlaq Ahmad Bhatti ◽  
Peng Xu ◽  
Adnan Aslam

A topological index is a numeric quantity related with the chemical composition claiming to correlate the chemical structure with different chemical properties. Topological indices serve to predict physicochemical properties of chemical substance. Among different topological indices, degree-based topological indices would be helpful in investigating the anti-inflammatory activities of certain chemical networks. In the current study, we determine the neighborhood second Zagreb index and the first extended first-order connectivity index for oxide network O X n , silicate network S L n , chain silicate network C S n , and hexagonal network H X n . Also, we determine the neighborhood second Zagreb index and the first extended first-order connectivity index for honeycomb network H C n .


2022 ◽  
Vol 04 (01) ◽  
pp. 656-669
Author(s):  
Basim Rashid ZOBAA ◽  
Osama Hamdan Abdullah RAHIM

The Holy Qur’an is the Book of God Almighty، and He described it، Glory be to Him, with several descriptions, and He told about it that it is a book that needs contemplation that leads you to the goal of the intended verses, and you think about the verses، rather the wall، to come up with a conception of it. The event, rather, depicts it from its different angles, and that is the camera in the Holy Qur’an, as it paints for us a vivid scene that pulsates with life in which all the meanings of life are dialogues and embodiment of what is not in a body, a chemical substance or a physical space. The place is separate from the time, but the study of the scene is fragmented, with a metaphor here or a metaphor there, this kills the scene and takes it out of its beauty. For this reason, the choice was made to study the scene in the Holy Qur’an، in order to clarify the beauty of the Holy Qur’an that is not limited to the verbal only, but comes out in the word to what is embodied، reasonable and metaphysical. This research is based on an introduction in which I talked about the scene in language and terminology, then she added to talk about the role of some linguists in approximating the term scene. As for the requirements of the research, the first of them is devoted to the study of material examples, as the importance of the material aspect in nature in general is mentioned in it, and this is supported by texts from the Noble Qur’an. As for the second، it was to study the moral examples، so I talked about the abstract morals, which are the perceptions of the mind, which do not possess tangible or tangible entities, and I included them with some examples of what was mentioned in the Holy Qur’an as well. As for the third, it was to study the unseen examples, in which I dealt with talking about the unseen، which is everything that is absent from man, corroborating that with what was mentioned in the Holy Qur’an. Finally, I say: This is a humble work in its chapter whose goal is to serve the word of God Almighty.


Author(s):  
M. M. Sidorovich ◽  
◽  
O. P. Kundelchuk ◽  

Determining the environmental safety of new synthetic plant growth regulators is an urgent problem. Spirocarbon derivatives were subjected to such determination by means of a specially developed system based on phytotests "germinated seeds". This system allows the values of biometric, cytological and biochemical parameters of the phytotest to determine the toxic, cytotoxic, genotoxic (mutagenic) effects and induction of molecular stress by the synthetic chemical substance being tested. This system was used to establish the biological properties of a new drug - a complex of spirocarbon with boric acid - in relation to five phytotests monocotyledons and dicotyledons plants. Phytotesting was performed in the spectrum of concentrations (10-7-10-2 mol/dm3) of this drug. It demonstrated either the absence or presence of a weak toxic effect on phytotests, which did not exceed 30%. The study showed that the plant growth regulator spirocarbon in combination with boric acid has growthregulating properties, the manifestation of which depends on the concentration of the drug and the species characteristics of plants. Only the maximum concentration (10-2 моль/дм3) of the tested drug is slightly toxic to plants. The obtained results testify to the biological efficiency and ecological safety of the synthesized drug. This allows us to recommend it for use in agricultural practice.


2021 ◽  
Vol 16 (1) ◽  
pp. 97-105
Author(s):  
F.V. Correia ◽  
S.F. Sales Junior ◽  
J.C. Moreira

Different pollutants can disrupt earthworm coelomocytes integrity and functions, and their responses can be applied as biomarkers of sublethal contaminant exposure. In this context, the aim of this study was to develop an in vitro protocol for coelomocyte extraction, maintenance and analysis with regard to soil health status and chemical toxicity profile assessments. The extrusion technique was first tested comparing previously depurated (purged stomach content) and non-depurated and resampled earthworms. After testing, earthworms were exposed to different 2,4D and chloroacetamide concentrations for methodology validation. The values of viability were not affected by food restriction since no statistical difference was observed between non-depurated (sample A) and depurated (sample B) organisms. Regarding to cell density, a significant (p<0;05) reduction of 22% was observed between non-depurated and depurated organisms, indicating that food restriction may affect cell density. However, the non-depurated resampling did not show a significant reduction, indicating that this assessment may not be affect by resampling of the same organism. For both chemical compounds, no change in cell viability was observed at all assessed concentrations and exposure times. However, for cell density, a mainly time-dependent effect was observed for organisms exposed to chloroacetamide, and concentration-dependent effect for organisms exposed to 2,4D. The proportion of immune system cells was altered, mainly after 24 h, with the increasing of granular amoebocytes proportion. The difference in the proportion of granular amoebocytes in earthworms exposed to 2,4D can be explained by the existence of recognition and elimination mechanisms for this chemical substance. Thus, assessments of pollutant responses with in vitro coelomocytes seem to be a powerful tool for ecotoxicological studies.


Author(s):  
Tanuja Yadav ◽  
Sachin Rohane

Acute toxicity study describes the adverse effects of a substance that result either from a single exposure or from multiple exposures in a short period of time. Whenever an investigator administered a chemical substance or herbal drug to a biological system different types of interactions can occur and a series of dose-related responses result. In most cases these responses are desired and useful, but there are a number of other effects which are not advantageous. These may or may not be harmful to the patient. Acute toxicity study is involved in estimation of LD50. Also it determines the therapeutic index i.e ratio between the lethal dose and the pharmacologically effective dose in the same strain and species. This article Review the methods so for utilized for the determination of acute toxicity.


Author(s):  
Ahmed Elshami ◽  
Stéphanie Bonnet ◽  
Abdelhafid Khelidj ◽  
Mohammad Farouk Abdelmagied

Author(s):  
Florin Sloată ◽  
Antoaneta Ene

This paper highlights an experimental model proposed for the management of nuclear materials containing natural uranium and thorium salts, based on technical and legislative methods. The investigated nuclear materials originate from laboratory chemicals with expired validity, having as manufacturers companies specialized in the manufacture of laboratory substances such as: Merck, Chemapol, Sigma Aldrich, Bucharest Reagent. The experimental program refers to several issues of great importance in the waste and environmental management, such as: a) the processing of radioactive substances containing nuclear materials and radioactive waste represented by solid objects contaminated with radionuclides from the radioactive series of U-238 and Th-232; b) gamma dose rate measurement during handling and processing of open sources of ionized radiation; c) measurement of suspicious contamination of the operating personnel which handles the equipment, including the materials used in the processing of open sources of ionizing radiation; and d) the inventory of nuclear materials according to the chemical formula, the mass of chemical substance, the mass of the nuclear element in each container and type of packaging. For the good development of processing these open sources of ionizing radiation containing nuclear materials, the ALARA principle (As Low As Reasonably Achievable) was applied, which is fundamental to the principles of radiation protection. All the measurements for determining the gamma dose rate and suspicious contamination were performed with the aid of a CoMo 170 radiometric device produced by Nuvia Instruments Gmbh Germany, equipped with a 170x100 mm2 PL detector with zinc sulfide calibrated with the aid of C-14, Co-60, Cs-137, U-238 and Am-241 radioactive isotopes and an external probe containing a scintillating crystal with sodium iodide enriched with thallium calibrated with Cs-137.


2021 ◽  
Vol 3 (2) ◽  
Author(s):  
Tasya Vita Brilian

Fixation is used to maintain tissue structure in its original form “life-like state” and can protect proteins and tissue components from degeneration. The solution commonly used is 10% NBF. Formaldehyde is chemical substance that is toxic and not environmentally friendly, several studies have shown alternative substitutes fixation, one of which is the honey solution. The study of Mohammed et al (2020) fixated tissue with honey 10% and 20% shown good coloring properties and similar clarity to fixated with formalin 10%. Honey has acidic and dehydrating properties allow most microorganisms to be killed so that tissues will last for a long time. The research objective is to findout the description of microscopic of mice (Mus musculus) kidney tissue which were fixation using 10% honey solution for 24 hours. The research is included in qualitative descriptive research. The research design used was a non-eksperimental with a purposive sampling study approach. The sample used was 32 preparation with total of microscopic overview is 160. Microscopic image of mice (Mus musculus) kidney tissue fixed using 10% honey solution for 24 hours in 80 visual fields were 12.5% of the preparations is not good and 87.5% is good preparations. The microscopic image of mice (Mus musculus) kidney tissue fixed using 10% NBF is better than of the microscopic image of mice (Mus musculus) kidney tissue fixed with 10% honey for 24 hours.


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