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1.
J Clin Med ; 13(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38610751

RESUMO

INTRODUCTION AND OBJECTIVE: Many scientific reports confirm a systematic decline in male semen parameters over the last decades. This phenomenon has been observed in all parts of the world, and its occurrence is associated, among others, with the hazardous effects of some environmental factors. The environmental factors for which the adverse effect on male fertility has been proven include water, air, and soil pollution, as well as electromagnetic fields and ionizing radiation. The aim of this article was the evaluation of the effect of selected environmental factors on male reproductive capacity based on an analysis of the current scientific reports. REVIEW METHODS: A systematic literature review was carried out using three databases: PubMed, EMBASE, and Scopus. The search was limited to the period from 2015 until the end of December 2023. Brief description of the state of knowledge: Environmental factors, such as heavy metals, tobacco smoke, pesticides, dioxins, furans, phthalates, and bisphenols, are well-tested substances that exert an adverse effect on male fertility. A harmful effect of electromagnetic fields and water and air pollution on reproductive functions may be expected; however, this has not been fully proven. SUMMARY: Results obtained by many researchers published to date should evoke great concern regarding the quality of the environment in which we live, as well as fears about the effect of environmental factors not only on male fertility, but also on all aspects of human health. The majority of environmental pollutants affect the male body by causing oxidative stress and through their effect on the endocrine system.

2.
Int J Mol Sci ; 24(21)2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37958777

RESUMO

Overactive bladder syndrome (OAB) is a prevalent condition that affects the elderly population in particular and significantly impairs quality of life. Imperatorin, a naturally occurring furocoumarin, possesses diverse pharmacological properties that warrant consideration for drug development. The aim of this study was to investigate the potential of imperatorin (IMP) to attenuate the cystometric and biochemical changes typically associated with retinyl acetate-induced overactive bladder (OAB) and to assess its viability as a pharmacological intervention for OAB patients. A total of 60 rats were divided into four groups: I-control, II-rats with rapamycin (RA)-induced OAB, III-rats administered IMP at a dose of 10 mg/kg/day, and IV-rats with RA-induced OAB treated with IMP. IMP or vehicle were injected intraperitoneally for 14 days. The cystometry and assessment of bladder blood flow were performed two days after the last dose of IMP. The rats were then placed in metabolic cages for 24 h. Urothelial thickness measurements and biochemical analyses were performed. Intravesical infusion of RA induced OAB. Notably, intraperitoneal administration of imperatorin had no discernible effect on urinary bladder function and micturition cycles in normal rats. IMP attenuated the severity of RA-induced OAB. RA induced increases in urothelial ATP, calcitonin gene-related peptide (CGRP), organic cation transporter 3 (OCT3), and vesicular acetylcholine transporter (VAChT), as well as significant c-Fos expression in all micturition areas analyzed, which were attenuated by IMP. Furthermore, elevated levels of Rho kinase (ROCK1) and VAChT were observed in the detrusor, which were reversed by IMP in the context of RA-induced OAB in the urothelium, detrusor muscle, and urine. Imperatorin has a mitigating effect on detrusor overactivity. The mechanisms of action of IMP in the bladder appear to be diverse and complex. These findings suggest that IMP may provide protection against RA-induced OAB and could potentially develop into an innovative therapeutic strategy for the treatment of OAB.


Assuntos
Furocumarinas , Bexiga Urinária Hiperativa , Humanos , Idoso , Ratos , Animais , Bexiga Urinária Hiperativa/tratamento farmacológico , Bexiga Urinária Hiperativa/etiologia , Bexiga Urinária Hiperativa/metabolismo , Qualidade de Vida , Bexiga Urinária , Furocumarinas/farmacologia , Furocumarinas/uso terapêutico , Quinases Associadas a rho
3.
Materials (Basel) ; 16(12)2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37374602

RESUMO

Interactions in a multicomponent Ni-Cr-Mo-Al-Re model alloy were determined by ab initio calculations in order to investigate the Re doping effect on Haynes 282 alloys. Simulation results provided an understanding of short-range interactions in the alloy and successfully predicted the formation of a Cr and Re-rich phase. The Haynes 282 + 3 wt% Re alloy was manufactured using the additive manufacturing direct metal laser sintering (DMLS) technique, in which the presence of the (Cr17Re6)C6 carbide was confirmed by an XRD study. The results provide useful information about the interactions between Ni, Cr, Mo, Al, and Re as a function of temperature. The designed five-element model can lead to a better understanding of phenomena that occur during the manufacture or heat treatment of modern, complex, multicomponent Ni-based superalloys.

4.
Sci Rep ; 12(1): 6296, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-35428807

RESUMO

The acute respiratory distress syndrome (ARDS) is a life-threatening clinical condition. The number of ARDS cases has risen dramatically recently but specific treatment options are limited. ARDS is associated with an overshooting inflammatory response and neutrophils play a central role in its pathogenesis. Neutrophils express the integrin Mac-1 on their surface which adopts a resting and activated conformation depending on leukocyte activation. The aim of this study was to investigate the anti-inflammatory effects of the unique activation-specific anti-Mac-1 DARPin 'F7' in a mouse model of ARDS. ARDS was induced by intratracheal lipopolysaccharide (LPS) instillation and the acute (day 1-4) and chronic phase (day 5-10) were studied. After expression and purification, F7, a control DARPin and PBS, were applied daily via the intraperitoneal route. Survival and weight loss were recorded. Histological analysis of lung sections, flow cytometric leukocyte analysis of blood and bronchioalveolar lavage (BALF) were performed. Moreover, protein concentration and cytokine levels were determined in the BALF. Treatment with F7 improved survival and reduced weight loss significantly compared to treatment with the control DARPin or PBS. Neutrophil count in the BALF and peripheral blood were significantly reduced in mice treated with F7. Histology revealed significantly reduced pulmonary inflammation in the F7 treated group. Treatment with DARPin F7 inhibited neutrophil accumulation, reduced signs of local and systemic inflammation and improved survival in a mouse model of ARDS. F7 may be a novel anti-inflammatory drug candidate for the treatment of severe ARDS.


Assuntos
Lesão Pulmonar Aguda , Síndrome do Desconforto Respiratório , Lesão Pulmonar Aguda/metabolismo , Animais , Repetição de Anquirina , Anti-Inflamatórios/farmacologia , Líquido da Lavagem Broncoalveolar , Modelos Animais de Doenças , Lipopolissacarídeos/metabolismo , Pulmão/patologia , Antígeno de Macrófago 1/metabolismo , Camundongos , Síndrome do Desconforto Respiratório/tratamento farmacológico , Redução de Peso
5.
Basic Res Cardiol ; 117(1): 16, 2022 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-35353230

RESUMO

Emergency hematopoiesis is the driving force of the inflammatory response to myocardial infarction (MI). Increased proliferation of hematopoietic stem and progenitor cells (LSK) after MI enhances cell production in the bone marrow (BM) and replenishes leukocyte supply for local cell recruitment to the infarct. Decoding the regulation of the inflammatory cascade after MI may provide new avenues to improve post-MI remodeling. In this study, we describe the influence of adenosine diphosphate (ADP)-dependent P2Y12-mediated signaling on emergency hematopoiesis and cardiac remodeling after MI. Permanent coronary ligation was performed to induce MI in a murine model. BM activation, inflammatory cell composition and cardiac function were assessed using global and platelet-specific gene knockout and pharmacological inhibition models for P2Y12. Complementary in vitro studies allowed for investigation of ADP-dependent effects on LSK cells. We found that ADP acts as a danger signal for the hematopoietic BM and fosters emergency hematopoiesis by promoting Akt phosphorylation and cell cycle progression. We were able to detect P2Y12 in LSK, implicating a direct effect of ADP on LSK via P2Y12 signaling. P2Y12 knockout and P2Y12 inhibitor treatment with prasugrel reduced emergency hematopoiesis and the excessive inflammatory response to MI, translating to lower numbers of downstream progeny and inflammatory cells in the blood and infarct. Ultimately, P2Y12 inhibition preserved cardiac function and reduced chronic adverse cardiac remodeling after MI. P2Y12-dependent signaling is involved in emergency hematopoiesis after MI and fuels post-ischemic inflammation, proposing a novel, non-canonical value for P2Y12 antagonists beyond inhibition of platelet-mediated atherothrombosis.


Assuntos
Infarto do Miocárdio , Animais , Hematopoese , Leucócitos , Camundongos , Camundongos Endogâmicos C57BL , Infarto do Miocárdio/metabolismo , Células-Tronco/metabolismo
6.
Materials (Basel) ; 14(10)2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-34068424

RESUMO

A new powder production method has been developed to speed up the search for novel alloys for additive manufacturing. The technique involves an ultrasonically agitated cold crucible installed at the top of a 20 kHz ultrasonic sonotrode. The material is melted with an electric arc and undergoes pulverization with standing wave vibrations. Several different alloys in various forms, including noble and metallic glass alloys, were chosen to test the process. The atomized particles showed exceptional sphericity, while powder output suitable for additive manufacturing reached up to 60%. The AMZ4 metallic glass powder remained amorphous below the 50 µm fraction, while tungsten addition led to crystallization in each fraction. Minor contamination and high Mn and Zn evaporation, especially in the finest particles, was observed in atomized powders. The innovative ultrasonic atomization method appears as a promising tool for material scientists to develop powders with tailored chemical composition, size and structure.

7.
Phys Chem Chem Phys ; 22(41): 23929-23951, 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33073813

RESUMO

The development of high-entropy alloys (HEAs) focuses on exploring compositional regions in multi-component systems with all alloy elements in equal or near-equal atomic concentrations. Initially it was based on the main idea that high mixing configurational entropy contributions to the alloy free energy could promote the formation of a single solid solution phase. By using the ab-initio based Cluster Expansion (CE) Hamiltonian model constructed for the quinary bcc Cr-Ta-Ti-V-W system in combination with Monte Carlo (MC) simulations, we show that the phase stability and chemical short-range order (SRO) of the equiatomic quinary and five sub-quaternary systems, as well as their derivative alloys, can dramatically change the order-disorder transition temperatures (ODTT) as a function of alloy compositions. In particular, it has been found, that the equiatomic quaternary Ta-Ti-V-W and Cr-Ta-Ti-W alloys had the lowest order-disorder transition temperature (500 K) among all the analysed equiatomic compositions. In all investigated alloy systems, the strongest chemical ordering has been observed between Cr and V, which led to the conclusion that decreasing the concentration of either Cr or V might be beneficial in terms of decreasing the ODTT. It also predicts that increasing concentration of Ti significantly decreases the ODTT. Our analysis of chemical SRO as a function of alloy composition allows to understand the microstructure evolution of HEAs as a function of temperature in excellent agreement with available experimental observations. Importantly, our free energy of mixing and SRO calculations predict that the origin of precipitates formed by Cr- and V-rich in the sub-quaternary Cr-Ta-V-W system is driven by the thermodynamics. The modelling results are in an excellent agreement with experimental observation of Cr and V segregation in the W0.38Ta0.36Cr0.15V0.11 alloy which in turns shows an exceptional radiation resistance.

8.
Entropy (Basel) ; 21(1)2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33266784

RESUMO

Configuration entropy is believed to stabilize disordered solid solution phases in multicomponent systems at elevated temperatures over intermetallic compounds by lowering the Gibbs free energy. Traditionally, the increment of configuration entropy with temperature was computed by time-consuming thermodynamic integration methods. In this work, a new formalism based on a hybrid combination of the Cluster Expansion (CE) Hamiltonian and Monte Carlo simulations is developed to predict the configuration entropy as a function of temperature from multi-body cluster probability in a multi-component system with arbitrary average composition. The multi-body probabilities are worked out by explicit inversion and direct product of a matrix formulation within orthonomal sets of point functions in the clusters obtained from symmetry independent correlation functions. The matrix quantities are determined from semi canonical Monte Carlo simulations with Effective Cluster Interactions (ECIs) derived from Density Functional Theory (DFT) calculations. The formalism is applied to analyze the 4-body cluster probabilities for the quaternary system Cr-Fe-Mn-Ni as a function of temperature and alloy concentration. It is shown that, for two specific compositions (Cr 25Fe 25Mn 25Ni 25 and Cr 18Fe 27Mn 27Ni 28), the high value of probabilities for Cr-Fe-Fe-Fe and Mn-Mn-Ni-Ni are strongly correlated with the presence of the ordered phases L1 2 -CrFe 3 and L1 0-MnNi, respectively. These results are in an excellent agreement with predictions of these ground state structures by ab initio calculations. The general formalism is used to investigate the configuration entropy as a function of temperature and for 285 different alloy compositions. It is found that our matrix formulation of cluster probabilities provides an efficient tool to compute configuration entropy in multi-component alloys in a comparison with the result obtained by the thermodynamic integration method. At high temperatures, it is shown that many-body cluster correlations still play an important role in understanding the configuration entropy before reaching the solid solution limit of high-entroy alloys (HEAs).

9.
Sci Rep ; 7: 39803, 2017 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-28059106

RESUMO

Multicomponent systems, termed High Entropy Alloys (HEAs), with predominantly single solid solution phases are a current area of focus in alloy development. Although different empirical rules have been introduced to understand phase formation and determine what the dominant phases may be in these systems, experimental investigation has revealed that in many cases their structure is not a single solid solution phase, and that the rules may not accurately distinguish the stability of the phase boundaries. Here, a combined modelling and experimental approach that looks into the electronic structure is proposed to improve accuracy of the predictions of the majority phase. To do this, the Rigid Band model is generalised for magnetic systems in prediction of the majority phase most likely to be found. Good agreement is found when the predictions are confronted with data from experiments, including a new magnetic HEA system (CoFeNiV). This also includes predicting the structural transition with varying levels of constituent elements, as a function of the valence electron concentration, n, obtained from the integrated spin-polarised density of states. This method is suitable as a new predictive technique to identify compositions for further screening, in particular for magnetic HEAs.

10.
J Phys Condens Matter ; 20(6): 064220, 2008 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-21693882

RESUMO

First-principles calculations of the phonon dispersion relations and the phonon density of states for ZnO polymorphs: wurtzite, zinc-blende, rocksalt structures, and as yet the experimentally undiscovered CsCl structure, are presented. All the phases were exposed to pressures ranging from 0 to 20 GPa. The pressure-temperature phase diagram of ZnO was constructed and compared to experimental data, where available.

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