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1.
Carbohydr Polym ; 327: 121697, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38171665

RESUMO

Application of the chemical demulsifiers is the best choice for breaking the water in crude oil (W/O) emulsions in the petroleum industry. Here, novel, environmentally friendly, efficient, and easily reusable Fe3O4 nanomagnetic compounds based on imidazolium-decorated cyclodextrin were successfully synthesized and applied to demulsify the water in crude oil (W/O) emulsions. At first, Fe3O4 nanoparticles were decorated with ß-cyclodextrin (ß-CD) to prepare Fe3O4@ß-CD@IL magnetic nanoparticles. Then, imidazole (Im) was separately reacted with 1-bromohexane and 1-bromodecane to prepare [Im-C6][Br] and [Im-C10][Br] ionic liquids, respectively. The prepared imidazolium-based ionic liquids were reacted with N-propyltriethoxysilane to synthesize [ImSi-C6][Br] and [ImSi-C10][Br]. Finally, [ImSi-Cn][Br] was immobilized on Fe3O4@ß-CD to obtain nanomagnetic demulsifiers. Structure of the synthesized compounds was confirmed using different methods such as FT-IR, NMR, and elemental analysis. TGA, VSM, and FESEM methods were used to investigate the thermal stability, magnetic properties, and the morphology, respectively. Fe3O4@ßCD and Fe3O4@ßCD@[ImSi-C10][Br] nanoparticles respectively showed the particle size in the range of 40-70 nm and 50-80 nm. After grafting the imidazolium-based ionic liquid on the surface of support, the magnetization number reduced from 25.6 emu/g for Fe3O4@ß-CD to 24.9 emu/g for Fe3O4@ß-CD@[ImSi-C10][Br]. Synthesized material employed to break the (10:90 and 30:70 Vol%) W/O emulsions at the concentration range of 1000-5000 ppm. The maximum demulsification efficiency (DE%) of 92 % was obtained using a Fe3O4@ß-CD@[ImSi-C10][Br] at 5000 ppm for (30:70 Vol%) W/O emulsion within 24 h. Interfacial tension (IFT) values decreased with increasing the DE%. The Fe3O4@ßCD@[ImSi-C10][Br] demulsifier was reused five times with acceptable yields. The cooperation of imidazolium and ß-CD in the green nanomagnetic demulsifiers led to the efficient demulsification of the W/O emulsions. The preparation of different ionic liquids or changing the counter anions are our potential future directions for this research. Demulsification at high demulsifier concentration can be considered a limitation of the nanomagnetic cyclodextrin decorated with ionic liquid. But due to the low amount of ionic liquid immobilized in the synthesized demulsifier, the cost of the final demulsifier is lower that other demulsifiers with full ionic liquid backbones, which increases its potential for industrial applications.

2.
Reprod Toxicol ; 120: 108453, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37536455

RESUMO

Methadone (Met) is the most common treatment for opioid addiction. Although Met is effective for treatment of opioid dependence, sexual dysfunctions and infertility have been reported as a major problem in patients under Met treatment. The present study aimed to evaluate the effect of melatonin and N-acetylcysteine (N) on morphine and Met-induced oxidative stress, apoptosis, suppression of blood sexual hormones, impairment in sperm parameters, and sexual dysfunction. Adult male Wistar rats (n = 66) were randomly divided into 11 equal groups (n = 6) as follows: control, sham, morphine, Met, Met+N, Met+ melatonin, Met+melatonin+N, morphine+ Met, morphine+Met+ melatonin, morphine+Met+N, and morphine+Met+ melatonin+N groups. On day 56 post-treatment, the blood was collected from the tail and the serum levels of sex hormones were evaluated, then the rats were sacrificed, and their bilateral testes and epididymis were retrieved for histological, immunohistochemical, molecular, testicular tissue stress oxidative status, and sperm parameters assays. Exposure to morphine, Met, and shift of morphine to Met resulted in testicular degeneration that can be attributed to generating the stress oxidative-induced- apoptotic testicular cell death and impairing spermatogenesis. Melatonin and N alone and particularly, in combination with each other improved testicular degeneration, sex hormone suppression, and testicular function mediated by increasing the testicular antioxidant capacity and inhibition of the apoptosis pathway. It's suggested that oral administration of antioxidants may be an effective treatment for attenuating some opioid-related testicular dysfunction and degeneration.


Assuntos
Melatonina , Doenças Testiculares , Animais , Masculino , Ratos , Acetilcisteína/farmacologia , Analgésicos Opioides/toxicidade , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Hormônios Esteroides Gonadais/metabolismo , Melatonina/metabolismo , Melatonina/farmacologia , Derivados da Morfina/metabolismo , Derivados da Morfina/toxicidade , Estresse Oxidativo , Ratos Wistar , Sêmen/metabolismo , Doenças Testiculares/patologia , Testículo
3.
Langmuir ; 39(28): 9627-9637, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37227803

RESUMO

Water in the crude oil forms emulsions that must be broken before refining processes. Here, the novel and versatile derivatives of imidazolium ionic liquids (ILs) containing triazole moiety [SIm-TazCn][Br] were synthesized via click chemistry and then grafted onto the cellulose (CEL) to prepare eco-friendly demulsifiers for breaking water-in-oil (W/O) emulsions. The prepared compounds with two kinds of alkyl chains named CEL[SIm-TazC6][Br] and CEL[SIm-TazC10][Br] were characterized and employed for demulsifying W/O (30:70 and 50:50 vol %) emulsions. Also, the effect of the type and concentration of each demulsifier on the phase separation and dehydration efficiency (DE) were investigated through the bottle test. According to the bottle test results, the CEL[SIm-TazC6][Br] derivative at 4000 ppm showed a good DE of 79% after 5 min, which increased to 82% after 24 h. The interfacial tension (IFT) of derivatives at different concentrations was measured. The minimum IFT value of 16.3 mN/m was obtained for CEL[SIm-TazC6][Br] with a shorter alkyl chain at 4000 ppm after 24 h. The green and efficient CEL-based surfactants significantly demulsified the W/O emulsions because of the collaboration between imidazolium and triazole moieties.

4.
Carbohydr Polym ; 302: 120406, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36604077

RESUMO

Separation of water and oil from water-in-oil (W/O) emulsion before transportation and refining is very important and critical. Ionic liquids (ILs) and their derivatives have recently attracted much attention as efficient chemical agents for breaking emulsions. So, here, a series of microcrystalline cellulose (MCC) grafted with imidazolium-based ionic liquids (IM-ILs) were synthesized, named as MCC@IM-ILs, and evaluated as eco-friendly surface-active agents for the separation of water from the crude oil. Structure of the synthesized compounds was confirmed by different characterization techniques. Dehydration efficiency percent (DE%) of the synthesized demulsifiers was measured and compared with each other. Synthesized MCC@IM-ILs showed an acceptable DE% to demulsify three kinds of W/O emulsions with different water content after 5 min. Concentration, alkyl chain length, and counter-anion of the synthesized MCC@IM-ILs play a key role in separating water from crude oil. Demulsifier with C10 alkyl chain length showed better DE% than the corresponding demulsifier with C6 alkyl chain length in the W/O (30:70 v/v) emulsion. Also, demulsifier with Br counter anion showed lower DE% than the corresponding BF4 ion-exchanged compound with higher hydrophilicity. Synthesized demulsifiers immobilized on ILs have significant advantages compared to unsupported ILs due to the use of green and economical cellulosic substrate.


Assuntos
Líquidos Iônicos , Petróleo , Emulsões , Líquidos Iônicos/química , Água/química , Ânions
5.
Andrology ; 10(3): 604-613, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34905299

RESUMO

BACKGROUND: Establishing an efficient, simple and inexpensive method for freezing ram epididymal sperm so that the quality and fertility of spermatozoa could be maintained for a longer period after thawing is of great practical value. OBJECTIVES: To optimize freezing and thawing protocol for ram epididymal sperm using either ethylene glycol (EG) or glycerol (GLY) as cryoprotectants (CPAs). Then, to evaluate the post-thaw longevity and in vitro fertility of spermatozoa that were frozen and thawed according to the optimized protocol. MATERIALS AND METHODS: At first, an optimum protocol for freezing and thawing sperm using EG or GLY were investigated, and the next experiments were performed using the spermatozoa that had been frozen and thawed according to the optimized protocol for each CPA. In the next experiments, frozen-thawed and fresh sperm were diluted in an isotonic culture medium and subsequently incubated at 39°C for 4 h. The motility characteristics and functional membrane integrity (FMI) of spermatozoa were evaluated after thawing, after dilution (t0 ), and after incubation (t4 ). The in vitro fertility of the spermatozoa was assessed at t0 and t4 . RESULTS: For both CPAs, the highest motility parameters and FMI was found for spermatozoa frozen at 3 cm above LN2 and thawed at 50 and 65°C (P < 0.05). In comparison to the spermatozoa of GLY group, the spermatozoa of the EG group had higher total and progressive motility at t0 , as well as higher FMI, total and progressive motility, and linearity at t4 (P < 0.05). Fertility of frozen-thawed sperm was higher than that of fresh sperm at t0 (P < 0.05). Incubation treatment increased the fertility of fresh sperm while decreased the fertility of frozen-thawed sperm, and this decline was more severe in GLY than in the EG group. CONCLUSION: Based on the findings, EG can be a more suitable CPA for freezing ram epididymal sperm.


Assuntos
Preservação do Sêmen , Animais , Criopreservação/métodos , Etilenoglicol/farmacologia , Fertilidade , Congelamento , Longevidade , Masculino , Preservação do Sêmen/métodos , Motilidade dos Espermatozoides , Espermatozoides
6.
Zygote ; 29(2): 102-107, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33079027

RESUMO

Culture conditions have a profound effect on the quality of in vitro-produced embryos. Co-culturing embryos with somatic cells has some beneficial effects on embryonic development. Considering the ability of stem cells to secrete a broad range of growth factors with different biological activities, we hypothesized that bovine amniotic membrane stem cells (bAMSCs) might be superior to bovine oviduct epithelial cells (BOECs) in supporting embryonic development and enhancing their cryo-survival. Bovine abattoir-derived oocytes were matured and fertilized in vitro. The resultant presumptive zygotes were then cultured up to the blastocyst stage in the following groups: (i) co-culture with bAMSCs, (ii) co-culture with BOECs, and (iii) cell-free culture (Con). Embryos that reached the blastocyst stage were vitrified and warmed, and their post-warming re-expansion, survival and hatching rates were evaluated after 72 h culture. Results showed that the cleavage, blastocyst, and 2 h post-warming re-expansion rates of embryos did not differ between groups. However, their survival rates in BOEC and bAMSC groups were significantly higher compared with the control (72.7, 75.6 and 37.5%, respectively, P < 0.05). In conclusion, our results showed that the cryo-survivability of IVF-derived bovine embryos could be improved through co-culturing with bAMSCs. Moreover, considering the possibility to provide multiple passages from bAMSCs compared with BOECs, due to their stemness properties and their ability to produce growth factors, the use of bAMSCs is a good alternative to BOECs in embryo co-culture systems.


Assuntos
Âmnio , Técnicas de Cultura Embrionária , Animais , Blastocisto , Bovinos , Técnicas de Cocultura , Criopreservação , Desenvolvimento Embrionário , Células Epiteliais , Feminino , Fertilização in vitro , Oviductos , Gravidez , Células-Tronco
7.
Reprod Domest Anim ; 54(3): 595-603, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30637807

RESUMO

Despite the numerous potential applications of oocyte cryopreservation, the poor success rate has limited its practical applications. In livestock, particularly in ovine, the oocytes have low developmental competence following vitrification/warming process. Considering the occurrence of osmotic and oxidative stresses during the vitrification/warming process, the application of antioxidants and osmolytes may improve the developmental competence of vitrified/warmed oocytes. In the present study, we aimed to evaluate the effects of the addition of ascorbic acid (AA) and N-acetyl cysteine (NAC) as antioxidants and glycine as an organic osmolyte either to the vitrification/warming solutions (VWS) or to the IVM medium on the developmental competence of vitrified/warmed ovine germinal vesicle stage oocytes. The survival rate in the vitrified groups was significantly lower than fresh ones. In vitrified/warmed oocytes, there was no significant difference in survival rate between supplemented and non-supplemented groups. The addition of AA and/or NAC to the VWS or IVM medium and adding glycine to the IVM medium reduced the proportion of apoptotic oocytes and fragmented embryos, which was reflected as an increase in the proportions of metaphase II stage oocytes and blastocyst production. The best result was achieved by supplementing the IVM medium with NAC. In our study condition, antioxidants and glycine could improve the developmental competence of vitrified/warmed ovine immature oocytes, especially when added during IVM.


Assuntos
Antioxidantes/farmacologia , Glicina/farmacologia , Oócitos/efeitos dos fármacos , Vitrificação/efeitos dos fármacos , Animais , Blastocisto/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Criopreservação/veterinária , Feminino , Técnicas de Maturação in Vitro de Oócitos/veterinária , Estresse Oxidativo/efeitos dos fármacos , Carneiro Doméstico
8.
J Biomater Appl ; 31(9): 1305-1316, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28447548

RESUMO

Methotrexate is one of the most effective drugs that is commonly used in the treatment of cancer. However, its application is limited due to low solubility, high toxicity and rapid metabolism. Therefore, in the present study, worm-like polymeric nanoparticles as carrier of methotrexate were prepared using biodegradable copolymers (mPEG-PCL). The impact of nanoparticles' geometry on the loading, delivery and drug's anti-cancer activity was investigated. The di-block copolymer mPEG-PCL was being synthesized by a ring opening polymerization of ɛ-caprolactone in the presence of mPEG as the initiator and Sn(oct)2 as the catalyst. It was used for the preparation of worm-like micelles and coated with silica, so that their structures are stable after drying. The synthesized copolymers and nanoparticles were characterized by FTIR, HNMR, GPC, XRD, TGA, DLS, and FE-SEM analyses. The efficiencies of drug loading and release of nanoparticles as in vitro, was studied by high performance liquid chromatography. The MTT method was used to estimate the toxicity on MCF-7 cell category. The obtained results showed that the nanoparticles were worm-like particles with less than 150 nm diameter and about 1 µm length. The loading and encapsulation efficiencies of drug by the worm-like nanoparticles were 3.5 ± 0.14% and 65.6 ± 0.12%, respectively, while they were obtained as 2.1 ± 0.08% and 26 ± 0.10%, respectively, for spherical nanoparticles. The methotrexate diffusional behavior of worm-like nanoparticles was compared with that of the spherical ones. On the other hand, the anti-cancer activity of MTX-loaded nanoparticles was more than the free drug. The results of the MTT assay showed strong and dose-dependent inhibition of cell (MCF-7 category) growth by the nanoparticles compared with MTX. The inhibitory concentrations (IC50 i.e. reduction viability of cell to 50%) obtained for worm-like, spherical nanoparticles and free drug (incubation times 72 h) were 8.25 ± 0.20, 9.15 ± 0.17, 12.28 ± 0.15 µg/mL, respectively. It can be concluded that application of non-spherical nanoparticles is a better and more effective strategy for controlled and slow release of methotrexate in the treatment of cancer.


Assuntos
Portadores de Fármacos/química , Metotrexato/farmacologia , Nanopartículas/química , Poliésteres/química , Polietilenoglicóis/química , Dióxido de Silício/química , Antineoplásicos , Sobrevivência Celular , Liberação Controlada de Fármacos , Humanos , Células MCF-7 , Metotrexato/administração & dosagem , Metotrexato/síntese química , Micelas , Tamanho da Partícula , Propriedades de Superfície
9.
Int J Dev Biol ; 60(4-6): 95-102, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27389982

RESUMO

Nuclear reprogramming of a differentiated cell in somatic cell nuclear transfer (SCNT) is a major concern in cloning procedures. Indeed, the nucleus of the donor cell often fails to express the genes which are a prerequisite for normal early embryo development. This study was aimed to evaluate the developmental competence and the expression pattern of some reprogramming related genes in bovine cloned embryos reconstructed with amniotic membrane stem cells (AMSCs) in comparison with those reconstructed with mesenchymal stem cells (MSCs) and adult fibroblasts (AF) as well as with in vitro fertilized (IVF) oocytes. In vitro matured abattoir-derived oocytes were considered as recipients and a hand-made cloning technique was employed for oocyte enucleation and nuclear transfer (NT) procedures. The expression pattern of genes involved in self-renewal and pluripotency (POU5F1, SOX2, NANOG), imprinting (IGF2, IGF2R), DNA methylation (DNMT1, DNMT3A), histone deacetylation (HDAC2), and apoptosis (BAX, BCL2) were evaluated in NT and IVF derived embryos. Despite the insignificant difference in cleavage rate between reconstructed and IVF oocytes, the blastocyst rate in the IVF group was higher than that of other groups. Among reconstructed oocytes, a higher blastocysts rate was observed in MSC-NT and AMSCs-NT derived embryos that were significantly higher than AF-NT derived ones. There were more similarities in the expression pattern of pluripotency and epigenetic modification genes between MSC-NT and IVF derived blastocysts compared with other groups. In conclusion, considering developmental competence, AMSCs, as alternative donors in SCNT procedure, like MSCs, were prone to have more advantage compared with AF.


Assuntos
Âmnio/citologia , Núcleo Celular/metabolismo , Oócitos/citologia , Células-Tronco/citologia , Âmnio/metabolismo , Animais , Apoptose/genética , Bovinos , Reprogramação Celular/genética , Metilação de DNA/genética , Feminino , Fertilização in vitro , Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Impressão Genômica/genética , Técnicas de Transferência Nuclear , Oócitos/metabolismo , Células-Tronco/metabolismo
10.
Arch Iran Med ; 15(4): 228-31, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22424041

RESUMO

BACKGROUND: Many studies show that congenital defects in infants conceived by assisted reproductive techniques (ART) are more than infants of normal conception (NC). The aim of this study is to determine the frequency of congenital anomalies in ART infants from Royan Institute and to compare congenital anomalies between two ART techniques.  METHODS: In a cross-sectional descriptive study, 400 ART infants from Royan Institute who resided in Tehran were selected by non-random, consecutive sampling. Infants were examined twice (until 9 months of age) by a pediatrician. Infants' congenital anomalies were described by each body system or organ and type of ART. Data were analyzed by SPSS version 16 and Fisher's exact test. RESULTS: The frequency of different organ involvement in the two examinations were: 40 (10%) skin, 25 (6.2%) urogenital system, 21 (5.2%) gastrointestinal tract, 13 (3.2%) visual, and 8 (2%) cardiovascular system. Major congenital defects in infants conceived by in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) were hypospadiasis, inguinal hernia, patent ductus arteriosus plus ventricular septal defect (PDA + VSD), developmental dysplasia of the hip, lacrimal duct stenosis during the first year of life, hydronephrosis and urinary reflux over grade III, undescending testis, ureteropelvic junction stenosis, and torticoli. CONCLUSIONS: Two-thirds of ART infants had no defects. A total of 7% of IVF and ICSI infants had one of the major abovementioned congenital anomalies. This rate was higher than NC infants (2%-3%). There was no difference between the ICSI and IVF group.


Assuntos
Anormalidades Congênitas/epidemiologia , Fertilização in vitro/efeitos adversos , Fertilização in vitro/estatística & dados numéricos , Anormalidades Congênitas/etiologia , Estudos Transversais , Criptorquidismo/epidemiologia , Permeabilidade do Canal Arterial/epidemiologia , Feminino , Comunicação Interventricular/epidemiologia , Hérnia Inguinal/congênito , Hérnia Inguinal/epidemiologia , Quadril/anormalidades , Humanos , Hidronefrose/congênito , Hidronefrose/epidemiologia , Hipospadia/epidemiologia , Lactente , Recém-Nascido , Irã (Geográfico)/epidemiologia , Aparelho Lacrimal/anormalidades , Masculino , Prevalência , Injeções de Esperma Intracitoplásmicas/efeitos adversos , Injeções de Esperma Intracitoplásmicas/estatística & dados numéricos , Torcicolo/congênito , Torcicolo/epidemiologia , Ureter/anormalidades
11.
Avicenna J Med Biotechnol ; 2(2): 107-11, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23407866

RESUMO

Improvements on embryo micromanipulation techniques led to the use of embryo biopsy in commercial embryo transfer programs for genetic analysis of preimplantation bovine embryos. The aim of this study was to evaluate the quality of bovine blastocyst derived from embryos biopsied at different pre-compacted morulae stages by assessment of cryosurvivability of the resulting blastocysts. The in vitro produced bovine embryos were subjected to biopsy at days 2, 3, and 4 post-insemination with different cell numbers (4 to 16-cells). Embryo cell biopsy was carried out in a 100 µl drop of H-SOF following pronase drilling by aspiration of one blastomere. The biopsied embryos were then cultured in SOFaaBSA co-cultured with oviduct cells-monolayer until blastocyst formation. The blastocysts were cryopreserved at room temperature after exposure of equilibration (glycerol 1.4 M for 5 min and then glycerol 1.4 M and ethylene glycol 3.6 M for 5 min) and vitrification solutions (3.4 M glycerol and 4.6 M ethylene glycol). The blastocysts were loaded into the center of 0.25 ml straws separated by air bubbles from 2 columns of sucrose 0.5 M and plunged immediately into liquid nitrogen. There was no significant difference in cryosurvivability of vitrified-warmed blastocysts derived form biopsied embryos at different pre-compacted morula stages. The quality of biopsy derived blastocysts was identical to that of non-biopsy derived ones in terms of post vitrifcation survival and hatching rates. In conclusion there was no preference between different times of embryo biopsy at precompacted morula stages in term of cryosurvivability of biopsy derived bovine blastocysts.

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