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Biomedicines ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 183
Author(s):  
Cristina Fraquelli ◽  
Jasmine Hauzinger ◽  
Christian Humpel ◽  
Maria Nolano ◽  
Vincenzo Provitera ◽  
...  

The serpinins are relatively novel peptides generated by proteolytic processing of chromogranin A and they are comprised of free serpinin, serpinin-RRG and pGlu-serpinin. In this study, the presence and source of these peptides were studied in the skin. By Western blot analysis, a 40 kDa and a 50 kDa protein containing the sequence of serpinin were detected in the trigeminal ganglion and dorsal root ganglia in rats but none in the skin. RP-HPLC followed by EIA revealed that the three serpinins are present in similar, moderate amounts in rat dorsal root ganglia, whereas in the rat skin, free serpinin represents the predominant molecular form. There were abundant serpinin-positive cells in rat dorsal root ganglia and colocalization with substance P was evident. However, much more widespread distribution of the serpinins was found in dorsal root ganglia when compared with substance P. In the skin, serpinin immunoreactivity was found in sensory nerves and showed colocalization with substance P; as well, some was present in autonomic nerves. Thus, although not exclusively, there is evidence that serpinin is a constituent of the sensory innervation of the skin. The serpinins are biologically highly active and might therefore be of functional significance in the skin.


BMC Cancer ◽  
2022 ◽  
Vol 22 (1) ◽  
Author(s):  
Tiina Mikkola ◽  
Rabeia Almahmoudi ◽  
Tuula Salo ◽  
Ahmed Al-Samadi

Abstract Background Interleukin (IL)-17 family is a group of six cytokines that plays a central role in inflammatory processes and participates in cancer progression. Interleukin-17A has been shown to have mainly a protumorigenic role, but the other members of the IL-17 family, including IL-17F, have received less attention. Methods We applied systematic review guidelines to study the role of IL-17F, protein and mRNA expression, polymorphisms, and functions, in cancer. We carried out a systematic search in PubMed, Ovid Medline, Scopus, and Cochrane libraries, yielding 79 articles that met the inclusion criteria. Results The findings indicated that IL-17F has both anti- and protumorigenic roles, which depend on cancer type and the molecular form and location of IL-17F. As an example, the presence of IL-17F protein in tumor tissue and patient serum has a protective role in oral and pancreatic cancers, whereas it is protumorigenic in prostate and bladder cancers. These effects are proposed to be based on multiple mechanisms, such as inhibition of angiogenesis, vasculogenic mimicry and cancer cell proliferation, migration and invasion, and aggravating the inflammatory process. No solid evidence emerged for the correlation between IL-17F polymorphisms and cancer incidence or patients’ prognosis. Conclusion IL-17F is a multifaceted cytokine. There is a clear demand for more well-designed studies of IL-17F to elucidate its molecular mechanisms in different types of cancer. The studies presented in this article examined a variety of different designs, study populations and primary/secondary outcomes, which unfortunately reduces the value of direct interstudy comparisons.


Author(s):  
Никита Александрович Клычков ◽  
Вячеслав Владимирович Симаков ◽  
Илья Владимирович Синёв ◽  
Дмитрий Александрович Тимошенко

С помощью золь-гель технологии синтезированы наноструктурированные газочувствительные пленки диоксида олова. Исследовано влияние температуры на проводимость сенсора в атмосфере очищенного воздуха, на величину отклика сенсора при воздействии паров изопропанола различной концентрации. На температурной зависимости проводимости плёнки диоксида олова в атмосфере чистого воздуха наблюдается локальный минимум. Уменьшение проводимости с ростом температуры в диапазоне 300...350С может быть связано с диссоциацией молекулярной формы адсорбированного кислорода. При температурах выше 350 °С проводимость возрастает из-за десорбции атомарной формы адсорбированного кислорода с поверхности газочувствительного слоя диоксида олова. Обнаружено, что наибольший отклик к газовым пробам достигается при рабочей температуре сенсора порядка 350°С. Предполагается, что это обусловлено наличием на поверхности атомарной формы хемосорбированного кислорода. Проведен анализ концентрационных и температурных зависимостей времени отклика сенсора при воздействии паров изопропанола. Время отклика сенсора монотонно уменьшается с повышением содержания примеси в газовых пробах, по-видимому, из-за увеличения скорости адсорбции частиц примеси из газовой фазы на поверхность газочувствительного слоя. Установлено, что зависимость времени отклика от рабочей температуры имеет аррениусовский вид, что может быть связано с термоактивированными адсорбционно-десорбционными и гетерогенными химическими процессами на поверхности активного слоя сенсора. Nanostructured gas-sensitive tin dioxide films have been synthesized by sol-gel technology. A conductivity vs temperature dependence of a gas sensor into atmosphere of synthetic air has been investigated. A response vs temperature dependence of a gas sensor into atmosphere of isopropanol vapors with various concentrations has been investigated. Local minimum on the temperature dependence of the tin dioxide film conductivity in clean air atmosphere were observed. A decrease in conductivity with increase temperature in the range of 300...350 °C can be associated with a dissociation molecular form of the adsorbed oxygen. At temperatures above 350 °C, conductivity increases because of desorption of the atomic form of the adsorbed oxygen on the surface of gas-sensitive tin dioxide film. The greatest response value is achieved at a sensor temperature equal to 350 °C. It is proposed that the reason is a domination of the atomic form of the chemisorbed oxygen on the surface. The analysis of response time vs concentration and response time vs temperature of gas sensor has been carried out. Sensor response time decreases monotonically with increase admixture substance in gas-probes, apparently because of increase in adsorption rate admixture particles on the surface of gas-sensitive film. It was found that the dependence of the response time on the operating temperature has an Arrhenius form. This may be associated with thermally activated adsorption-desorption processes and heterogeneous chemical reactions on the surface of sensor active layer.


Molecules ◽  
2021 ◽  
Vol 27 (1) ◽  
pp. 55
Author(s):  
Alexander L. Kustov ◽  
Leonid M. Kustov

The formation of complexes and disproportionation of nitrogen oxides (NO, N2O) on cationic forms of LTA, FAU, and MOR zeolites was investigated by diffuse-reflectance IR spectroscopy. N2O is adsorbed on the samples under study in the molecular form and the frequencies of the first overtone of the stretching vibrations ν10–2 and the combination bands of the stretching vibrations with other vibrational modes for N2O complexes with cationic sites in zeolites (ν30–1 + ν10–1, ν10–1 + δ0–2) are more significantly influenced by the nature of the zeolite. The presence of several IR bands in the region of 2400–2600 cm−1 (the ν10–1 + δ0–2 transitions) for different zeolite types was explained by the availability of different localization sites for cations in these zeolites. The frequencies in this region also depend on the nature of the cation (its charge and radius). The data can be explained by the specific geometry of the N2O complex formed, presumably two-point adsorption of N2O on a cation and a neighboring oxygen atom of the framework. Adsorption of CO or CH4 on the samples with preliminarily adsorbed N2O at 20–180 °C does not result in any oxidation of these molecules. NO+ and N2O3 species formed by disproportionation of NO are capable of oxidizing CO and CH4 molecules to CO2, whereas NOx is reduced simultaneously to N2 or N2O. The peculiarities in the behavior of cationic forms of different zeolites with respect to adsorbed nitrogen oxides determined by different density and localization of cations have been established.


2021 ◽  
Vol 3 (6) ◽  
pp. 47-60
Author(s):  
Robert A. Sizov

Experimental and theoretical studies of the author (period: 1968 - present) have shown that true sources of magnetic field are magnetic fundamental particles (magnetic charges), and not moving electrons. The main reason for the vicious ignorance of magnetic charges in physics is the super-hard conditions of confinement of these particles in atoms and substance which are cardinally different from the confinement of electrons. Magnetic charges together with electric charges form the shells of atoms which in reality are electromagnetic, and not electronic. The orbital electromagnetic currents in atomic shells are sources of the gravitational field which is the vortex electromagnetic field and is described by vortex vector rot[E–H]. Depending on the state polarization of vortex vectors rot[E–H] in compositions of the atomic gravitational fields its subdivided into paragravitational (PGF) and ferrogravitational fields (FGF). The main process defining formation of chemical compounds is the gravito-chemical binding or compression of atoms by the forces of the paragravitational "Dark Energy" which is realized between PGF atoms-sources. Between the atoms emitting PGF and FGF the effect of Gravitational levitation is realized the forces of which push the atoms away from each other. Therefore, the combination of carbon atoms (PGF sources) and hydrogen atoms (FGF–sources) with the formation of hydrocarbon molecules can be realized only if the hydrogen atoms are in molecular form (1H2). In the composition of water, within the framework of the chemical formula H2O, two stable isomorphic molecular structures are realized, the gravito-chemical bond in which is carried out, respectively of the hydrocarbon scenario described above, as well as under conditions of unidirectional ferropolarization of the gravitational fields of atoms in molecule and of the implementation of the so-called hydrogen bond. The external (technical) ferrogravitational field violates the initial (paragravitational) state of gravitational fields in interatomic regions what leads to the formation of positive (gravitational) “Dark energy” the forces of which break interatomic chemical bonds and leads to molecular decays. This process, by analogy with process of electrolysis, can be referred to as ferrogravitolysis. The Author's technology for the decomposition of water molecules by means of FGF is a technical analogue of the natural process of water decomposition which is realized in the cells of leaves of green plants and algae. The intensity of technical FGF, and, consequently, the efficiency of the process of decomposition water molecules can be thousands of times higher than the efficiency of its natural decomposition in plant cells, which makes it possible to obtain cheap green hydrogen for wide practical use. In addition, the effectiveness of the impact of (technical) FGF on the state of gravitational fields in the interatomic regions of molecules and the implementation of the process of their decomposition is many times greater than the capabilities of the currently used electric field.


2021 ◽  
Vol 2086 (1) ◽  
pp. 012003
Author(s):  
N E Chernenko ◽  
S V Balakirev ◽  
M M Eremenko ◽  
M S Solodovnik

Abstract In this work, experimental studies of the influence of the arsenic molecular form (di-or tetramers) and substrate temperature on the crystallization of In/GaAs droplet nanostructures during droplet epitaxy have been carried out. We have shown the critical influence of the temperature and arsenic molecular form on the reproducibility of the characteristics of an array of self-organizing InAs nanostructures during crystallization. We also showed that a decrease in the initial In droplet size has a positive effect on the reproducibility of the parameters of the InAs nanostructures arrays. Our work also showed important role of substrate temperature at the crystallization stage.


2021 ◽  
Vol 348 ◽  
pp. 130715
Author(s):  
Bingru Li ◽  
Pengyuan Sun ◽  
Jianhui Zhen ◽  
Wenwen Gong ◽  
Zhiyong Zhang ◽  
...  

Inorganics ◽  
2021 ◽  
Vol 9 (11) ◽  
pp. 80
Author(s):  
Li Zhou ◽  
Huadong Zhu ◽  
Wen Zeng

Sulphide gas is an impurity that affects the quality of natural gas, which needs reasonable storage and transportation. In this work, we investigated the adsorption structure and electronic behavior of hydrogen sulfide (H2S), carbonyl sulfur (COS), and methyl mercaptan (CH3SH) on sulphide gas molecules on pure and vacant α-Fe2O3(001) surfaces by density functional theory with geometrical relaxations. The results show that H2S and CH3SH are mainly adsorbed in the form of molecules on the pure Fe2O3(001) surface. On the vacant α-Fe2O3(001) surface, they can be adsorbed on Fe atoms in molecular form and by dissociation. The absolute value of the adsorption energy of H2S and CH3SH on the vacancy defect α-Fe2O3 surface is larger, and the density of states show that the electron orbital hybridization is more significant, and the adsorption is stronger. The charge differential density and Mulliken charge population analysis show that the charge is rearranged and chemical bonds are formed. The affinity of H2S to the vacancy α-Fe2O3(001) surface is slightly higher than that of CH3SH, while COS molecules basically do not adsorb on the α-Fe2O3(001) surface, which may be related to the stable chemical properties of the molecules themselves.


2021 ◽  
Vol 2058 (1) ◽  
pp. 012021
Author(s):  
A Kulichenko ◽  
D S Farrakhova ◽  
D V Yakovlev ◽  
Yu S Maklygina ◽  
A A Shiryaev ◽  
...  

Abstract This paper presents the results of using intraoperative fluorescence diagnostics (FD) with the endoscopic video system to increase the efficiency of photodynamic therapy (PDT). The molecular form of chlorin e6 was used as a photosensitizer (PS). All patients received an intravenous administration drug based on chlorin e6 at the concentration of 1 mg/kg. Diagnostics and therapy were carried out in 4 patients diagnosed by malignant neoplasms of the lateral surface of the tongue. Determination of the boundaries by changing the signal of the fluorescence intensity of the tumor was carried out before PDT and after PDT. The efficiency of PDT was assessed by the fluorescent signal of the tumor decreasing when compared with non-pathological normal tissue. The FD method allows to determine accurately the actual size of the tumor and its borders. All patients underwent PDT influenced by the therapeutic laser with a generation wavelength of 660 nm. It is shown that the using of fluorescence diagnostics improves the quality of the photodynamic therapy, since it is possible to assess the photobleaching of the drug during the operation.


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