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1.
Mol Biol Rep ; 51(1): 72, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38175282

RESUMO

BACKGROUND: Red ginseng and propolis are well-known antioxidants that have been related to a reduction in oxidative stress. OBJECTIVE: This study evaluated the efficiency of red ginseng and propolis, either in powder or as nano-forms against dexamethasone-induced testicular oxidative challenges in adult male albino rats. METHODS: Forty rats were divided into 8 equal groups including control negative group that was given vehicle (DMSO), control positive group that was administered dexamethasone in addition to the nano-propolis, nano-ginseng, nano-propolis + dexamethasone, nano ginseng+dexamethasone, propolis+dexamethasone and ginseng + dexamethasone groups. Serum, semen and tissue samples were obtained. RESULTS: Lower testosterone levels, higher levels of MDA, and lower levels of total antioxidant capacity in serum, as well as impaired semen quality and a disturbed histopathological picture of both the testis and seminal glands, were all observed as significant negative effects of dexamethasone. These findings were confirmed by lower gene expression profiles of CYP11A1, StAR, HSD-3b, Nrf-2 and ACTB-3b in testicular and seminal gland tissues. The most powerful anti-dexamethasone effects were obtained with either propolis in nanoform or conventional ginseng. CONCLUSION: Propolis nano-formulation and ginseng in conventional form could be considered excellent candidates to ameliorate the oxidative stress provoked by dexamethasone, however, neither nano-ginseng nor conventional propolis showed such effects.


Assuntos
Ascomicetos , Panax , Própole , Masculino , Animais , Ratos , Própole/farmacologia , Análise do Sêmen , Antioxidantes/farmacologia , Dexametasona/farmacologia
2.
Reprod Domest Anim ; 58(8): 1146-1155, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37378547

RESUMO

The use of multiple ovulation and embryo transfer (MOET) technology in the dairy cattle industry has increased dramatically in recent decades for the production of offspring from genetically superior cows. Yet, its long-term ramifications on adult performance have not been adequately clarified. Therefore, this study targeted comparing dairy heifers born after the transfer of in vivo-produced embryos (MOET-heifers, n = 400) and those born after artificial insemination (AI-heifers, n = 340). The performance of MOET-heifers and AI-heifers was compared from birth till completion of the first lactation regarding health, fertility and some lactational performance parameters. The transcript abundance of several genes was also assessed in peripheral blood leukocytes (PBWC). Results showed greater pre-weaning mortalities, greater likelihood of being culled as a nulliparous heifer and younger age at first insemination in AI-heifers (p < .001). At their first calving, primiparous MOET-heifers experienced a greater (p < .01) incidence of stillbirth compared to primiparous AI-heifers. In spite of that, primiparous AI-heifers were more likely to be culled due to infertility (p < .001), took a greater number of inseminations to achieve pregnancy (p < .01) and displayed a longer first calving interval. There was a similar lactational performance between the two groups. Upregulation of the transcript levels of TAC3, LOC522763, TFF2, SAXO2, CNKSR3 and ALAS2 was interestingly observed in primiparous MOET-heifers, compared to primiparous AI-heifers. In conclusion, MOET-heifers were less likely to be culled during the first year of life, had superior reproductive performance versus AI-heifers during their first lactation and expressed upregulation of genes associated with fertility.


Assuntos
Inseminação Artificial , Reprodução , Gravidez , Bovinos , Animais , Feminino , Inseminação Artificial/veterinária , Inseminação Artificial/métodos , Transferência Embrionária/veterinária , Transferência Embrionária/métodos , Lactação , Nível de Saúde
3.
J Perinat Med ; 50(3): 294-299, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-34523303

RESUMO

OBJECTIVES: To compare between the effectiveness and safety of two different daily doses of vaginal progesterone (400 vs. 200 mg) in the prevention of preterm labor in twin pregnancy. METHODS: This is a prospective single-blinded randomized controlled trial conducted on 100 primi-gravida who had twin pregnancy and attended the antenatal clinic of a University hospital. They were equally and randomly allocated into two arms each containing 50 patients. Arm 1 received 400 mg and arm 2 received 200 mg vaginal progesterone daily at bed time starting from 14 weeks of pregnancy to 36 weeks. Transvaginal ultrasound was performed for assessment of the length of cervix at 14 and 22 weeks. RESULTS: Both arms of the current study were comparable regarding the cervical length at 14 and 22 weeks, mean gestational age at delivery, incidence of pre-term delivery, birth weight of the first twin. Second twin in addition to the average weight of both twins. No statistical significance differences between two arms regarding incidence of early neonatal death. NICU, mechanical ventilation, length of admission in NICU for the first twin. Second twin as well as both twins. CONCLUSIONS: Vaginal progesterone treatment with different doses was tolerable, but wasn't effective in the prevention of preterm labor in twin pregnancy.


Assuntos
Trabalho de Parto Prematuro/prevenção & controle , Gravidez de Gêmeos , Progesterona/administração & dosagem , Administração Intravaginal , Adulto , Medida do Comprimento Cervical , Relação Dose-Resposta a Droga , Feminino , Humanos , Recém-Nascido , Gravidez , Estudos Prospectivos , Método Simples-Cego
4.
Reprod Domest Anim ; 57(8): 856-863, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35437877

RESUMO

This study aimed to determine effects of exposure of recipient dairy heifers to heat stress (THI ≥ 73) during the oestrous cycle coinciding with embryo transfer (ET) on the risk of pregnancy establishment after transfer of in vivo produced embryos. Recipients exposed to THI values ≥73 during Days zero (recipient estrus), 7 (day of ET), 14 (seven days after ET), 15 and 16 (maternal recognition of pregnancy) of the ET cycle were considered as heat-stressed heifers (n = 254), while heifers in the control group (n = 470) were not exposed to THI ≥ 73 at any of the previous days. Results revealed no significant effects of any of the investigated factors on the risk of pregnancy following ET. However, the mean THI above 77 was associated with a drastic numerical decrease in PR/ET (36.63%), when compared to a mean THI 72 (78.78%). In addition, PR/ET after transfer of second- and third-grade embryos were numerically lower in heat-stressed recipients, compared with first-grade embryos (41.17% vs. 56.36%, respectively). Our findings confirmed that transfer of blastocysts was associated with numerically higher PR/ET in heat-stressed and control recipients, as compared to morula stage. Interestingly, PR/ET tended to be higher when sexed embryos were transferred to the control recipients compared with heat-stressed ones. In conclusion, PR/ET in dairy heifers was not significantly affected by heat stress during critical windows of their oestrous cycle coinciding with ET, whereas transfer of sexed embryos gives lower results under conditions of heat stress.


Assuntos
Transferência Embrionária , Embrião de Mamíferos , Animais , Blastocisto , Bovinos , Transferência Embrionária/métodos , Transferência Embrionária/veterinária , Feminino , Resposta ao Choque Térmico , Gravidez
5.
Reprod Domest Anim ; 57(11): 1353-1362, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35864721

RESUMO

The physiological effects of dietary boron (B) supplementation for farm animals specifically goat on male fertility are still scarce and need deep investigation. Thus, the current study was designed to investigate how adding B to the diet of male goats affected their testicular and thyroid activity. For that purpose, twelve male goats were divided randomly into two groups (six animals each); control group that was fed the basal diet and B group that was fed the basal diet containing 70 mg B/kg diet for 6 months. Serum samples were collected at different intervals, while testicular biopsies were obtained at the end of the experiment. The results showed that 6 months of dietary B supplementation resulted in a significant increment in serum B concentration. The results of repeated measure analysis showed that there were significant GROUP and TIME × GROUP interactions effects on blood testosterone levels (F = 119.408, p = .000 and F = 6.794, p = .013, respectively), demonstrating that compared with control, B supplementation caused a significant rise in serum testosterone levels over time. However, the mean animal body weights and the serum levels of triiodothyronine (T3) and thyroxine (T4) were kept comparable with the control ones at the different time points. The most striking finding is that B supplementation increased significantly the mRNA expression of the CYP17A1 which is essential for steroidogenesis (p < .001). In addition, a histological examination of testicular tissue corroborated our findings and demonstrated that B supplementation had a positive effect. As a result, B might be considered an excellent food supplement that could be safely added to the male goats' diet at the current dose to improve their reproductive capacity.


Assuntos
Boro , Cabras , Animais , Masculino , Ração Animal/análise , Boro/farmacologia , Dieta/veterinária , Suplementos Nutricionais , Cabras/fisiologia , Testosterona , Glândula Tireoide
6.
Reprod Domest Anim ; 56(1): 153-160, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33176025

RESUMO

The goal was to investigate the relationship among mRNA expressions of anti-Mullérian hormone (AMH), follicle-stimulating hormone receptor (FSHR) and responses to superovulation (SO) in embryo donor dairy cows. Holstein cows (n = 19) were submitted to a standard SO protocol, with twice daily FSH treatments, and artificially inseminated. Prior to SO (Day 0), relative mRNA expressions of AMH and FSHR in blood were determined for all cows. Day 7 embryos were collected and were graded to determine superovulatory response for each donor. Results showed that relative mRNA expressions of AMH and FSHR were positively correlated (R2  = 0.94). Relative mRNA expressions of both AMH and FSHR were positively correlated with total embryos (R2  = 0.68 and 0.69, respectively), total transferable embryos (R2  = 0.92 and 0.97, respectively) and total grade 1 embryos (R2  = 0.54 and 0.59, respectively). Further, transcript abundances of AMH and FSHR positively associated with milk production of donor cows, and meanwhile, they were negatively associated with days in milk (DIM) at submission of cows to SO (p < .05) protocol. The relative mRNA expression of AMH was higher (p < .05) in donor cows <5 years of age. However, age of donor at superovulation did not influence mRNA expression of FSHR. Collectively, we infer that the mRNA expressions of AMH and FSHR prior to superovulation can predict donor cows' positive response to superovulation.


Assuntos
Hormônio Antimülleriano/metabolismo , Bovinos/fisiologia , Receptores do FSH/metabolismo , Superovulação/efeitos dos fármacos , Animais , Hormônio Antimülleriano/genética , Indústria de Laticínios , Transferência Embrionária/veterinária , Embrião de Mamíferos , Feminino , Lactação , RNA Mensageiro/metabolismo , Receptores do FSH/genética , Coleta de Tecidos e Órgãos/veterinária
7.
Photochem Photobiol Sci ; 17(4): 491-498, 2018 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-29594308

RESUMO

A metal oxide-heterojunction photocatalyst is developed to harvest sunlight, store the energy in electrons, and apply the stored energy in water treatment. Light-absorbing nanoparticular and nanotubular TiO2 are hybridized with electron-storing WO3 at different weight ratios of TiO2 to WO3 (e.g., TW25 represents a composite of 25 wt% TiO2 and 75 wt% WO3). The ability of the TW composite to utilize the stored electrons is examined for the reduction of hexavalent chromium (Cr(vi)). In the photoelectrochemical (PEC) tests, irradiation using simulated sunlight (AM 1.5, 100 mW cm-2) leads to a rapid shift in the open-circuit potential (OCP) of the TW electrodes to the negative potential region (photocharging process). The termination of irradiation causes a gradual shift of the OCP to the positive potential region over 20 h (discharging process). Spiked Cr(vi) added to the solution with pre-photocharged TW electrodes is efficiently removed; the kinetics of this process depends on the TW composition (25, 50, or 75 wt%), TiO2 morphology (particular or tubular), initial Cr(vi) concentration (0.125 or 0.25 ppm), and whether the conditions are aerated or non-aerated. Based on this knowledge, TW composite-embedded inorganic membranes are synthesized and charged using sunlight. For Cr(vi) removal, single-pass and continuous circulation filtration systems are employed. The fraction of Cr(vi) removed from the circulation system is ∼30% in 4 h, which is 1.5 times that removed using the single-pass filtration system (∼20%). An X-ray photoelectron spectroscopy analysis of the TW membranes used for Cr(vi) removal reveals that Cr is not sorbed in the membrane. The W(vi) in WO3 is partially reduced to W(6-x)+ upon photocharging and is oxidized during the reduction of Cr(vi), leading to the co-existence of W6+ and W(6-x)+.

8.
J Environ Sci (China) ; 74: 168-176, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30340670

RESUMO

This study investigates the removal of arsenite (As(III)) from water using dithionite activated by UV light. This work evaluated the removal kinetics of As(III) under UV light irradiation as affected by dithionite dose and light intensity, and characterized the nature of the precipitated solids using XPS and SEM-EDS. Photolysis of dithionite was observed by measuring dithionite concentration using UV absorbance at 315nm. This study also investigated the effect of UV light path length on soluble As concentrations to understand resolubilization mechanisms. Total soluble As concentrations were observed to decrease with reaction time due to reduction of arsenite to form solids having a yellow-orange color. The removal mechanism was found to be reductive precipitation that formed solids of elemental arsenic or arsenic sulfide. However, these solids were observed to resolubilize at later times after dithionite had been consumed. Resolubilization of As was prevented and additional As removal was obtained by frequent dosing of dithionite throughout the experiment. As(III) removal is attributed to photolysis of dithionite by UV light and production of reactive radicals that reduce As(III) and convert it to solid forms.


Assuntos
Arsenitos/química , Arsenitos/isolamento & purificação , Precipitação Química , Ditionita/química , Raios Ultravioleta , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Oxirredução , Fotólise , Soluções
9.
Environ Sci Technol ; 51(22): 13372-13379, 2017 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-29083909

RESUMO

Solar-driven heterogeneous photocatalysis has been widely studied as a promising technique for degradation of organic pollutants in wastewater. Herein, we have developed a sulfite-enhanced visible-light-driven photodegradation process using BiOBr/methyl orange (MO) as the model photocatalyst/pollutant system. We found that the degradation rate of MO was greatly enhanced by sulfite, and the enhancement increased with the concentration of sulfite. The degradation rate constant was improved by 29 times in the presence of 20 mM sulfite. Studies using hole scavengers suggest that sulfite radicals generated by the reactions of sulfite (sulfite anions or bisulfite anions) with holes or hydroxyl radicals are the active species for MO photodegradation using BiOBr under visible light. In addition to the BiOBr/MO system, the sulfite-assisted photocatalysis approach has been successfully demonstrated in BiOBr/rhodamine B (RhB), BiOBr/phenol, BiOI/MO, and Bi2O3/MO systems under visible light irradiation, as well as in TiO2/MO system under simulated sunlight irradiation. The developed method implies the potential of introducing external active species to improve photodegradation of organic pollutants and the beneficial use of air pollutants for the removal of water pollutants since sulfite is a waste from flue gas desulfurization process.


Assuntos
Fotólise , Poluentes da Água , Catálise , Luz , Sulfitos
10.
Gynecol Endocrinol ; 33(3): 199-202, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27809622

RESUMO

This study evaluated the effects of nitric oxide donor's treatment on the pregnancy rate and uterine blood flow in patients with unexplained infertility undergoing clomiphene citrate stimulation and intrauterine insemination. A total of 120 patients were randomly allocated to a control group who received 100 mg clomiphene citrate daily from day 5 to 9 of cycle plus placebo vaginal tablets, and a study group received clomiphene citrate plus isosorbide mononitrate 10 mg vaginal tablets. Vaginal ultrasound was done before treatment and every other day starting from day 12 of cycle to count mature follicles and ovulation was triggered by IM injection of 10 000 IU hCG when one follicle measured 18 ≥ mm followed by intrauterine insemination after 36 h. The endometrial thickness, uterine arteries resistance and pulsation indices, and endometrial vascular flow and vascular flow indices were measured before treatment and at day of hCG injection. Results were analyzed after one cycle treatment using the Mean ± SD, the Student t test and the Fisher Exact test. Significant result was considered at p values <0.05. The study group had significant higher pregnancy rate/cycle, higher endometrial and lower uterine artery blood flow indices (p < 0.05).


Assuntos
Infertilidade Feminina/terapia , Inseminação Artificial , Dinitrato de Isossorbida/análogos & derivados , Doadores de Óxido Nítrico/uso terapêutico , Indução da Ovulação , Artéria Uterina/efeitos dos fármacos , Vasodilatadores/uso terapêutico , Administração Intravaginal , Adulto , Clomifeno/uso terapêutico , Egito , Endométrio/irrigação sanguínea , Endométrio/efeitos dos fármacos , Feminino , Fármacos para a Fertilidade Feminina/uso terapêutico , Fase Folicular/efeitos dos fármacos , Hospitais Universitários , Humanos , Infertilidade Feminina/fisiopatologia , Dinitrato de Isossorbida/administração & dosagem , Dinitrato de Isossorbida/uso terapêutico , Doadores de Óxido Nítrico/administração & dosagem , Projetos Piloto , Gravidez , Taxa de Gravidez , Fluxo Sanguíneo Regional/efeitos dos fármacos , Comprimidos , Artéria Uterina/fisiopatologia , Resistência Vascular/efeitos dos fármacos , Vasodilatadores/administração & dosagem , Adulto Jovem
12.
Z Naturforsch C J Biosci ; 72(3-4): 99-105, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28121619

RESUMO

Two local hydrogen-evolving strains of purple nonsulfur bacteria have been isolated, characterized, and identified as Rhodopseudomonas sp. TUT (strains Rh1 and Rh2). Lactate followed by succinate and malate supported the highest amounts of H2 production, growth (O.D.660nm, proteins and bacteriochlorphyll contents), nitrogenase activity, and uptake hydrogenase; the least of which was acetate. Alginate-immobilized cells evolved higher hydrogen amounts than free cell counterparts. Rh1 was more productive than Rh2 at all circumstances. Lactate-dependent hydrogen evolution was more than twice that of acetate, due to ATP productivity (2/-1, respectively), which is limiting to the nitrogenase activity. The preference of lactate over other acids indicates the feasibility of using these two strains in hydrogen production from dairy wastewater.


Assuntos
Ácido Acético/farmacologia , Células Imobilizadas/efeitos dos fármacos , Metabolismo Energético , Hidrogênio/metabolismo , Ácido Láctico/farmacologia , Rodopseudomonas/efeitos dos fármacos , Ácido Acético/metabolismo , Trifosfato de Adenosina/metabolismo , Alginatos/química , Bacterioclorofilas/biossíntese , Células Imobilizadas/metabolismo , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Hidrogenase/biossíntese , Cinética , Ácido Láctico/metabolismo , Malatos/metabolismo , Malatos/farmacologia , Nitrogenase/biossíntese , Fotossíntese/fisiologia , Rodopseudomonas/metabolismo , Ácido Succínico/metabolismo , Ácido Succínico/farmacologia
13.
Water Sci Technol ; 72(10): 1780-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26540539

RESUMO

A new versatile electrochemical sensor based on poly(styrene-co-acrylic acid) PSA/SiO2/Fe3O4/AuNPs/lignin (L-MMS) modified glassy carbon electrode (GCE) was developed for the selective detection of trace trinitrotoluene (TNT) from aqueous media with high sensitivity. The fabricated magnetic microspheres were characterized by transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray photoelectron spectroscopy (XPS). L-MMS films were cast on the GCE surface to fabricate the TNT sensing electrode. The limit of detection (LOD) of TNT determined by the amperometric i-t curve reached 35 pM. The lignin film and well packed Fe3O4/AuNPs facilitated the pre-concentration of trace TNT on the electrode surface resulting in a fast amperometric response of 3 seconds near the detection limit. The high sensitivity and excellent catalytic activity of the modified electrode could be attributed to the lignin layer and highly packed Fe3O4/AuNPs on the electrode surface. The total recovery of TNT from tapwater and seawater matrices was 98% and 96%, respectively. The electrode film was highly stable after five repeated adsorption/desorption cycles. The new electrochemical sensing scheme provides a highly selective, sensitive and versatile assay for the in-situ detection of TNT in complex water media.


Assuntos
Técnicas Eletroquímicas/métodos , Trinitrotolueno/análise , Poluentes Químicos da Água/análise , Acrilatos/química , Carbono/química , Técnicas Eletroquímicas/instrumentação , Eletrodos , Desenho de Equipamento , Ouro/química , Lignina/química , Limite de Detecção , Microscopia Eletrônica de Transmissão , Nanopartículas , Espectroscopia Fotoeletrônica , Poliestirenos/química , Sensibilidade e Especificidade , Dióxido de Silício/química
14.
Biol Trace Elem Res ; 202(5): 2143-2157, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37682394

RESUMO

Bisphenol A (BPA) is a widely used endocrine disruptor that represents a significant risk to male reproductive function. Zinc (Zn) is vital for appropriate development of testes and to guarantee optimal testicular function and spermatogenesis. Our goal was to investigate if zinc oxide (ZnO), either in conventional or nanoformulation, could safeguard adult male rats' reproductive performance against the damaging effects of BPA. Signaling expression of CYP11A1 and Nrf-2 in the testis, testicular oxidant-antioxidant status, Bax/Bcl-2 apoptotic ratio, and histological examination of various reproductive organs were all evaluated. Twenty-eight adult male albino rats were divided randomly into 4 groups (7 animals each) including the control, BPA, conventional zinc oxide (cZnO) + BPA, and zinc oxide nanoparticles (ZnO-NPs) + BPA groups. The study was extended for 2 successive months. Our findings revealed strong negative effects of BPA on sperm cell characteristics such as sperm motility, viability, concentration and abnormalities. Additionally, BPA reduced serum levels of testosterone, triiodothyronine (T3), and thyroxine (T4). Also, it evoked marked oxidative stress in the testes; elevating malondialdehyde (MDA) and reducing total antioxidant capacity (TAC). BPA significantly downregulated testicular mRNA relative expression levels of CYP11A1 and Nrf-2, compared to control. Testicular apoptosis was also prompted by increasing Bax/ Bcl-2 ratio in testicular tissue. Histopathological findings in the testes, epididymis, prostate gland, and seminal vesicle confirmed the detrimental effects of BPA. Interestingly, cZnO and ZnO-NPs significantly alleviated all negative effects of BPA, but ZnO-NPs performed better. In conclusion, our findings point to ZnO, specifically ZnO-NPs, as a viable treatment for BPA-induced testicular dysfunction.


Assuntos
Compostos Benzidrílicos , Fenóis , Óxido de Zinco , Ratos , Masculino , Animais , Óxido de Zinco/toxicidade , Antioxidantes/metabolismo , Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , Proteína X Associada a bcl-2/metabolismo , Motilidade dos Espermatozoides , Sêmen/metabolismo , Testículo , Estresse Oxidativo , Expressão Gênica
16.
Environ Eng Sci ; 30(5): 264-271, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23840160

RESUMO

A new class of treatment processes called advanced reduction processes (ARPs) is proposed. ARPs combine activation methods and reducing agents to form highly reactive reducing radicals that degrade oxidized contaminants. Batch screening experiments were conducted to identify effective ARPs by applying several combinations of activation methods (ultraviolet light, ultrasound, electron beam, and microwaves) and reducing agents (dithionite, sulfite, ferrous iron, and sulfide) to degradation of four target contaminants (perchlorate, nitrate, perfluorooctanoic acid, and 2,4 dichlorophenol) at three pH-levels (2.4, 7.0, and 11.2). These experiments identified the combination of sulfite activated by ultraviolet light produced by a low-pressure mercury vapor lamp (UV-L) as an effective ARP. More detailed kinetic experiments were conducted with nitrate and perchlorate as target compounds, and nitrate was found to degrade more rapidly than perchlorate. Effectiveness of the UV-L/sulfite treatment process improved with increasing pH for both perchlorate and nitrate. We present the theory behind ARPs, identify potential ARPs, demonstrate their effectiveness against a wide range of contaminants, and provide basic experimental evidence in support of the fundamental hypothesis for ARP, namely, that activation methods can be applied to reductants to form reducing radicals that degrade oxidized contaminants. This article provides an introduction to ARPs along with sufficient data to identify potentially effective ARPs and the target compounds these ARPs will be most effective in destroying. Further research will provide a detailed analysis of degradation kinetics and the mechanisms of contaminant destruction in an ARP.

17.
Membranes (Basel) ; 13(8)2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37623808

RESUMO

Ultrafiltration (UF) polymeric membranes are widely used in water treatment and support desalination and gas separation membranes. In this article, we enhance the performance of Polysulfone (PSF) mixed matrix membranes (MMMs) by dispersing different concentrations of thermally reduced graphene (TRG) nanofillers. The UF PSF-TRG MMMs were fabricated via the phase inversion process, and the impact of TRG loading on the characteristics of the membrane, including hydrophilicity, porosity, roughness, and morphology, were analyzed using a contact angle measurement, atomic force microscopy (AFM), scanning electron microscopy (SEM), and dynamic mechanical analysis. Incorporating TRG into the PSF matrix led to favorable effects in the instantaneous de-mixing during phase inversion, increasing the porosity and hydrophilicity of MMMs and improving the mechanical properties of the membranes. Moreover, membrane performance was examined to remove dispersed oil from oil-water emulsion and support air-dehumidification membranes. MMM performance in terms of flux and oil rejection was superior to the control PSF membrane. Incorporating 0.25% TRG into PSF resulted in a 70% water flux increase and higher oil rejection compared to the control PSF membrane. As a support for air-dehumidification membranes, the MMM also demonstrated enhanced humidity reduction and an over 20% increase in water vapor permeance over the control PSF membrane. These results indicate that the PSF-TRG MMMs are an excellent candidate for reliable oil-water separation and as a support for air-dehumidification membranes.

18.
Membranes (Basel) ; 13(7)2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37505044

RESUMO

Porous low-pressure membranes have been used as active membranes in water treatment and as support for thin-film composite membranes used in water desalination and gas separation applications. In this article, microfiltration polysulfone (PSf)mixed-matrix membranes (MMM) containing amine-functionalized graphene oxide (GO-NH2) were fabricated via a phase inversion process and characterized using XPS, SEM, AFM, DMA, XRD, and contact angle measurements. The effect of GO-NH2 concentration on membrane morphology, hydrophilicity, mechanical properties, and oil-water separation performance was analyzed. Significant enhancements in membrane hydrophilicity, porosity, mechanical properties, permeability, and selectivity were achieved at very low GO-NH2 concentrations (0.05-0.2 wt.%). In particular, the water permeability of the membrane containing 0.2 wt.% GO-NH2 was 92% higher than the pure PSf membrane, and the oil rejection reached 95.6% compared to 91.7% for the pure PSf membrane. The membrane stiffness was also increased by 98% compared to the pure PSf membrane. Importantly, the antifouling characteristics of the PSf-GO-NH2 MMMs were significantly improved. When filtering 100 ppm bovine serum albumin (BSA) solution, the PSf-GO-NH2 MMMs demonstrated a slower flux decline and an impressive flux recovery after washing. Notably, the control membrane showed a flux recovery of only 69%, while the membrane with 0.2 wt.% GO-NH2 demonstrated an exceptional flux recovery of 88%. Furthermore, the membranes exhibited enhanced humidity removal performance, with a permeance increase from 13,710 to 16,408. These results indicate that the PSf-GO-NH2 MMM is an excellent candidate for reliable oil-water separation and humidity control applications, with notable improvements in antifouling performance.

19.
Sci Total Environ ; 879: 162569, 2023 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-36871724

RESUMO

Nanomaterials have gained huge attention with their wide range of applications. This is mainly driven by their unique properties. Nanomaterials include nanoparticles, nanotubes, nanofibers, and many other nanoscale structures have been widely assessed for improving the performance in different applications. However, with the wide implementation and utilization of nanomaterials, another challenge is being present when these materials end up in the environment, i.e. air, water, and soil. Environmental remediation of nanomaterials has recently gained attention and is concerned with removing nanomaterials from the environment. Membrane filtration processes have been widely considered a very efficient tool for the environmental remediation of different pollutants. Membranes with their different operating principles from size exclusions as in microfiltration, to ionic exclusion as in reverse osmosis, provide an effective tool for the removal of different types of nanomaterials. This work comprehends, summarizes, and critically discusses the different approaches for the environmental remediation of engineered nanomaterials using membrane filtration processes. Microfiltration (MF), ultrafiltration (UF), and nanofiltration (NF) have been shown to effectively remove nanomaterials from the air and aqueous environments. In MF, the adsorption of nanomaterials to membrane material was found to be the main removal mechanism. While in UF and NF, the main mechanism was size exclusion. Membrane fouling, hence requiring proper cleaning or replacement was found to be the major challenge for UF and NF processes. While limited adsorption capacity of nanomaterial along with desorption was found to be the main challenges for MF.

20.
Toxicol Res (Camb) ; 12(5): 930-942, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37915476

RESUMO

Background: Bisphenol A (BPA), an endocrine-disrupting chemical (EDC), is ubiquitous in our environment and poses a significant threat to male fertility. Date seeds (DSs) are used in folk medicine due to their antioxidant activity. Aim: The purpose of this study was to assess the beneficial effects of DSs, whether in powder or nanoparticle form, against BPA-induced testicular oxidative challenges and apoptosis, aided by inspection of specific genes linked to fertility, oxidative stress and intrinsic mitochondrial pathway of apoptosis. Methods: Thirty-five adult male albino rats were equally divided into 5 groups including control, BPA, BPA + date seeds powder "DSP", BPA + date seed nanoparticle 1/10 (DSNP 1/10) and BPA + DSNP 1/20 groups. Results: TEM showed that the ball-mill method was effective to form DSNP with an average size of 20 nm. BPA significantly impaired sperm motility, morphology, viability and concentration. It also reduced serum testosterone levels and evoked marked oxidative stress in the testes. Additionally, serum levels of triiodothyronine and thyroxine were extremely reduced. Moreover, testicular mRNA relative expression levels of CYP11A1 and Nrf-2 were markedly downregulated. Testicular apoptosis was also promoted whereas Bax/Bcl-2 ratio was profoundly elevated. Histological pictures of the testes, epididymis, seminal vesicles and prostate confirmed the unfavorable effects of BPA. Surprisingly, we first demonstrated that DSs, specifically the nanoparticle form, strongly alleviated all of BPA's negative effects, with DSNP 1/20 achieving the best results. Conclusion: Therefore, DSNP in both doses could be regarded as an ideal candidate for abating the male reproductive challenges caused by BPA.

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