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1.
Heliyon ; 9(11): e21593, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38027807

RESUMO

Pasteurization is a vital process to destroy harmful enzymes. This process is very critical to obtain quality tomato paste. In this study, Computational Fluid Dynamics (CFD) has been used to design a shell and tube heat exchanger on an industrial scale and to simulate heat transfer in order to visualize this process and present it to the industry. In this research, a three-dimensional CFD model was simulated using ANSYS FLUENT commercial software. Also, using the Herschel-Bulkley model, the behavior of viscosity in the pasteurization process of tomato paste has been explained. In this stage of the production line, the tomato paste enters a shell and tube heat exchanger at 65 °C and reaches 80 °C at the outlet. Compared with the experimental data, the output temperature of tomato paste predicted by CFD simulation reached 79 °C. In addition, thermophysical properties of tomato paste were measured, and these exact values were used for simulation. Also, the evaluation of this heat exchanger with three hot water inlet mass flow rates has been done in order to provide the results to the factory to avoid spending more energy. And the simulation results showed that the output temperature of tomato paste at three different mass flow rates did not change less than the mass flow rates measured in the factory, and also the output visualizations from this research can be suitable for presenting to the industry and benefiting from them.

2.
Iran J Vet Res ; 24(2): 136-142, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37790113

RESUMO

Abstract. Background: The efficiency of ovine in vitro embryo production remains low yet. Aims: The present study evaluated the effect of different concentrations of gamma (γ)-oryzanol in maturation or culture media on in vitro ovine oocytes and embryo developments. Methods: Morphologically normal COCs were aspirated from ovine ovaries, subjected to maturation media supplemented with 0, 2.5, 5, 10, 20, 50, and 100 µM γ-oryzanol, then processed for conventional in vitro fertilization and culture to assess their potential to cleave and develop to blastocyst. Another group of COCs was matured and fertilized. Presumptive zygotes were subjected to culture in drops of media supplemented with 0, 2.5, 10, 20, and 50 µM γ-oryzanol, and the developments of embryos were assessed under 7% and 20% O2 levels. A control group of no supplementation was included in each experiment. Results: The expansion of cumulus cover and survival rate tended to decrease with concentrations of 20, 50, and 100 µM in maturation media, suggesting an overdose effect. The cleavage and total blastocyst rates were significantly higher for oocytes matured at 5 µM γ-oryzanol. The presumptive zygotes cultured in supplemented media showed significantly higher cleavage and total blastocyst rates with concentrations of 5 and 10 µM γ-oryzanol (P<0.04) in both 7% and 20% O2 levels. Conclusion: These results represent the first study showing a significant positive effect of the γ-oryzanol supplement on in vitro ovine oocyte and embryo development, at optimal concentrations of 5 µM in maturation, and 5 and 10 µM in embryo culture media.

3.
SAR QSAR Environ Res ; 32(6): 495-520, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34074200

RESUMO

Robust and reliable QSAR models were developed to predict half-maximal inhibitory concentration (IC50) values of hepatitis C virus NS3/4A protease inhibitors from the Monte Carlo technique. 524 HCV NS3/4A protease inhibitors were extracted from the scientific literature to create a reasonably large set. The models were developed using CORAL software by using two target functions namely target function 1 (TF1) without applying the index of ideality of correlation (IIC) and target function 2 (TF2) that uses IIC. The constructed models based on TF2 were statistically more significant and robust than the models based on TF1. The determination coefficients (r2) of training and test sets were 0.86 and 0.88 for the best split based on TF2. The promoters of the increase/decrease of activity were also extracted and interpreted in detail. The model interpretation results explain the role of different structural attributes in predicting the pIC50 values of hepatitis C virus NS3/4A protease inhibitors. Based on the mechanistic model interpretation results, eight new compounds were designed and their pIC50 values were predicted based on the average prediction of ten models.


Assuntos
Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Inibidores de Proteases/farmacologia , Relação Quantitativa Estrutura-Atividade , Antivirais/química , Método de Monte Carlo , Inibidores de Proteases/química
4.
Complement Ther Clin Pract ; 44: 101389, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33932731

RESUMO

INTRODUCTION: The interest in CAM among cancer patients is constantly growing and about 50% already used CAM alongside cancer therapy. Little is known on the factors influencing patients' choice of type of CAM used. METHODS: A questionnaire consisting of two validated instruments (the ASKU (Allgemeine Selbstwirksamkeit Kurzskala), the PAM 13-D (Patient Activation Measure) and the structured AKKOM questionnaire on CAM usage was distributed at a German university hospital. RESULTS: 639 patients (male 32.9%, female 63.2%; gynecological cancer 41%, gastrointestinal 19.2%, urogenital 15.6%) took part. 60% had used CAM in the last 3 months (biological 73%, holistic 63%, mind-body-methods 62%). Participants up to 30 years preferred biologically (p = 0.001), while women with gynecological cancer favored holistic based methods (p < 0.0001). There was no association between patients' beliefs on cancer causes and the chosen CAM method. CONCLUSION: Improving knowledge in patients on cancer etiology and treatments could facilitate the understanding of additional complementary treatments.


Assuntos
Terapias Complementares , Neoplasias , Feminino , Humanos , Masculino , Neoplasias/terapia , Inquéritos e Questionários
5.
Arch Razi Inst ; 75(2): 169-177, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32621445

RESUMO

Bovine subclinical mastitis is regarded as a devastating disease due to the economic costs imposed on dairy husbandry. Moreover, it is a hazard in the public sector in the cases of zoonotic bacteria because of the potential role of unpasteurized milk and dairy products to propagate the infectious agent to the human food chain. The present study aimed to evaluate the frequency, virulence content, and antimicrobial resistance profile of Shiga toxin-producing Escherichia coli (STEC) strains isolated from bovine subclinical mastitis in Kurdistan Province, West of Iran. A total of 400 bovine subclinical mastitis milk samples recognized in the California Mastitis Test were collected aseptically and analyzed for the presence of E. coli phenotypically and molecularly. The isolates were genotypically screened for stx1, stx2, and eae genes. Furthermore, O157:H7 STEC strain was searched among the isolates in a duplex polymerase chain reaction. The antimicrobial resistance scheme of the isolates was determined using the agar disk diffusion method. In general, 173 (43.25%) E. coli isolates were detected among which 39 (22.54%) isolates were STEC. The frequency of STEC virulence genotypes was stx2 (25 isolates, 64.10%), stx2+eae (6 isolates, 15.38%), stx1+stx2 (6 isolates, 15.38%), and stx1+stx2+eae (2 isolates, 5.12%). In addition, three O157: H7 strains were identified with the genetic content of stx1+stx2+eae (2 isolates) and stx1+stx2 (1 isolate). The most prevalent antimicrobial resistance was observed against streptomycin, tetracycline, and ampicillin. Gentamycin, amoxicillin-clavulanic acid, and trimethoprim-sulfadiazine were the most effective antibiotics against O157 strains, whereas gentamycin, ciprofloxacin, and nitrofurantoin were effective against non-O157 strains. The results revealed the significant role of STEC in bovine subclinical mastitis in the studied region. In addition, the distribution of O157:H7 strain and high prevalence of multidrug resistance among the isolates is a matter of concern. Therefore, there is a potential threat of human infection following the consumption of contaminated milk with STEC in Kurdistan Province, Iran.


Assuntos
Farmacorresistência Bacteriana/genética , Infecções por Escherichia coli/veterinária , Mastite Bovina/microbiologia , Leite/microbiologia , Escherichia coli Shiga Toxigênica/isolamento & purificação , Escherichia coli Shiga Toxigênica/patogenicidade , Animais , Bovinos , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Feminino , Genótipo , Irã (Geográfico) , Escherichia coli Shiga Toxigênica/genética , Virulência
6.
Appl Opt ; 57(28): 8193-8198, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30461769

RESUMO

We have theoretically studied the Goos-Hänchen (GH) shifts of both the reflected and transmitted probe beams emerging from a cavity consisting of a hybrid system of a coupled quantum dot (QD) nanostructure and a metallic nanoparticle (MNP). It is realized that the GH shifts in the transmitted and reflected light beams can be enhanced due to the surface plasmon effect in the MNP. Also, it is shown that by adjusting the distance between QD and MNP and polarization control between probe field and major axis of the hybrid system, the simultaneous negative and positive GH shifts in reflected and transmitted light beams can occur. Moreover, the effects of the intensity and detuning of the coupling light on the GH shift properties of the reflected and transmitted lights have been discussed. We have found that under different parametric conditions of the hybrid system, the GH shifts of the reflected and transmitted light beams can be adjusted by tuning the intensity and controlling the detuning of the coupling field. The results show that our proposed model may be used for future optical sensor devices based on MNP hybrid systems.

7.
Mater Sci Eng C Mater Biol Appl ; 56: 223-32, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26249584

RESUMO

Mesoporous silica nanoparticles with a hexagonal structure (SBA-15) were synthesized and modified with (3-aminopropyl) triethoxysilane (APTES), and their performance as a carrier for drug delivery system was studied. Chemical structure and morphology of the synthesized and modified SBA-15 were characterized by SEM, BET, TEM, FT-IR and CHN technique. Betamethasone Sodium Phosphate (BSP) as a water soluble drug was loaded on the mesoporous silica particle for the first time. The response surface method was employed to obtain the optimum conditions for the drug/silica nanoparticle preparation, by using Design-Expert software. The effect of time, pH of preparative media, and drug/silica ratio on the drug loading efficiency was investigated by the software. The maximum loading (33.69%) was achieved under optimized condition (pH: 1.8, time: 3.54 (h) and drug/silica ratio: 1.7). The in vitro release behavior of drug loaded particles under various pH values was evaluated. Finally, the release kinetic of the drug was investigated using the Higuchi and Korsmeyer-Peppas models. Cell culture and cytotoxicity assays revealed the synthesized product doesn't have any cytotoxicity against human bladder cell line 5637. Accordingly, the produced drug-loaded nanostructures can be applied via different routes, such as implantation and topical or oral administration.


Assuntos
Betametasona/análogos & derivados , Nanopartículas/química , Dióxido de Silício/química , Betametasona/química , Betametasona/farmacocinética , Betametasona/farmacologia , Linhagem Celular Tumoral , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/farmacologia , Humanos , Concentração de Íons de Hidrogênio , Porosidade
8.
Micron ; 64: 20-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24981209

RESUMO

In the present study, different amounts of graphene nanosheets (GNSs) were added to the 4043 aluminum alloy powders by using the mechanical alloying method to produce the composite filler wires. With each of the produced composite filler wires, one all-weld metal coupon was welded using the gas tungsten arc (GTA) welding process. The microstructure, mechanical properties and fracture surface morphology of the weld metals have been evaluated and the results are compared. As the amount of GNSs in the composition of filler wire is increased, the microstructure of weld metal was changed from the dendritic structure to fine equiaxed grains. Furthermore, the tensile strength and microhardness of weld metal was improved, and is attributed to the augmented nucleation and retarded growth. From the results, it was seen that the GNSs/Al composite filler wire can be used to improve the microstructure and mechanical properties of GTA weld metals of aluminum and its alloys.

9.
Reprod Domest Anim ; 46(1): 87-94, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20456664

RESUMO

The objective of this study was to determine the effects of various methods of sperm pre-treatment on male pronuclear (MPN) formation and subsequent development of ovine embryos derived from in vitro-matured oocytes and intracytoplasmic sperm injection (ICSI). The effect of treatment of injected oocytes with dithiothreitol (DTT) on embryo development was also assessed. In Exp. 1, the injected oocytes with non-treated sperm were activated with three different procedures. The cleavage and blastocyst rates in those activated with DTT was lower (p<0.05) than those activated with either ionomycin (Io) +6-dimethylaminopurine (6-DMAP) or DTT + I + 6-DMAP. In Exp. 2, the effects of sperm pre-incubated with DTT, sodium dodecyl sulphate (SDS) or DTT + SDS as well as two-time frozen/thawed sperm (without cryoprotectant) on MPN formation and oocyte activation were examined. The non-treated sperm served as controls. The MPN formation in DTT + SDS group was higher (p<0.05) than other groups except for freeze-thaw group. No difference in the rate of activated ICSI oocytes was observed among groups. In Exp. 3, the effect of pre-treatment of sperm on subsequent development of ICSI embryos and blastocyst cell numbers were examined. The rates of cleavage and blastocyst formation as well as the blastocyst cell numbers were similar among the pre-treated and control groups. In conclusion, pre-treatment of sperm with DTT + SDS positively affected MPN formation, although the subsequent development capacity of the resulting embryos remained limited. Moreover, DTT was not effective on oocyte activation compared with Io + 6-DMAP after ICSI.


Assuntos
Núcleo Celular/fisiologia , Desenvolvimento Embrionário , Ovinos , Injeções de Esperma Intracitoplásmicas/veterinária , Espermatozoides/efeitos dos fármacos , Adenina/análogos & derivados , Adenina/farmacologia , Animais , Blastocisto/citologia , Blastocisto/fisiologia , Núcleo Celular/efeitos dos fármacos , Fase de Clivagem do Zigoto/fisiologia , Ditiotreitol/farmacologia , Feminino , Masculino , Oócitos/efeitos dos fármacos , Oócitos/fisiologia , Oócitos/ultraestrutura , Inibidores de Proteínas Quinases/farmacologia , Dodecilsulfato de Sódio/farmacologia , Injeções de Esperma Intracitoplásmicas/métodos , Espermatozoides/ultraestrutura
10.
Br J Dermatol ; 164(1): 83-96, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20849516

RESUMO

BACKGROUND: Overproduction of collagen and its abnormal assembly are hallmarks of keloid scars. Type I/III collagen ratios are altered in keloids compared with normal skin. Fibroblasts from different sites in keloid tissue, perilesional compared with intralesional and extralesional sites, show differential apoptosis and contraction. Additionally, early vs. later cell culture passages display differential collagen expression. We therefore hypothesize that keloid fibroblasts from the growing margin of the keloid express higher levels of collagen type I and III, and that collagen production is altered by extended cell culture passage. OBJECTIVES: (i) To measure collagen I and III at mRNA and protein levels quantitatively in keloid fibroblasts, growth media and tissue sections; and (ii) to perform tissue staining for collagen I and III expression in different lesional sites. METHODS: Keloid fibroblast cultures from intralesional, perilesional and extralesional sites (n = 8 separate keloid cases, yielding 64 biopsy samples) were established from passage 0 to passage 3. Collagen I and III mRNA was quantified using quantitative reverse transcription-polymerase chain reaction. We also measured the protein levels quantitatively by developing a highly specific and sensitive capture sandwich enzyme-linked immunosorbent assay. A novel in-cell Western blotting was carried out in addition to haematoxylin and eosin and Herovici staining on keloid tissue sections for collagen I and III. RESULTS: Collagen types I and III were significantly higher (P < 0·03) in fibroblasts from the growing margin (perilesional site) compared with extralesional and intralesional keloid biopsy sites. As the passage number increased, the amount of collagen I significantly (P < 0·05) decreased and the collagen I/III ratio also decreased. CONCLUSIONS: Our data show that cells from the growing margin of keloid scars have a higher production of collagen I and III compared with other lesional sites. Additionally, temporal extension of cell passage affects collagen production. Clinically these findings may influence selection and interpretation of extended cell passage and provide future direction for lesional site-specific therapy in keloid scars.


Assuntos
Colágeno Tipo III/biossíntese , Colágeno Tipo I/biossíntese , Fibroblastos/metabolismo , Queloide/patologia , Pele/metabolismo , Adolescente , Adulto , Biópsia , Western Blotting , Feminino , Humanos , Masculino , Reação em Cadeia da Polimerase/métodos , RNA Mensageiro/metabolismo , Pele/patologia , Adulto Jovem
11.
Zygote ; 18(4): 331-8, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20579410

RESUMO

The effects of the age of cell donor animal on in vitro development of ovine nuclear transfer (NT) embryos were investigated. Somatic donor cells were obtained from two different sources: (1) adult cells (adult fibroblast cells; AFC and adult cumulus cells; ACC); and (2) fetal fibroblasts (40-day-old; FFC-40 and 65-day-old; FFC-65). The fibroblast cell lines were used for NT procedures within 4-13 subpassages. While the cumulus cells were used as non-cultured (fresh) cells. The in vitro matured abattoir-derived oocytes were considered as recipients. No differences in the rates of fusion (75.7, 77.7, 76.3 and 86.7%) and cleavage (80.1, 84.3, 77.8 and 74%) were detected among couplets reconstructed with FFC-40, FFC-65, AFC and ACC, respectively. Blastocyst formation rate of those oocytes reconstructed with FFC-40 was higher (18%; p < 0.001) than those reconstructed with FFC-65 (13%) and AFC (10.9) and comparable with those reconstructed with ACC (17.5%). When the effect of passage number was analysed within groups (FFC-40, FFC-65 and AFC) there were no significant differences in fusion, cleavage and blastocyst rates between reconstructed oocytes. The present study demonstrates that the fetal and adult fibroblasts as well as fresh cumulus cells are comparable in their ability to attain cell fusion and embryonic cleavage. Moreover, the blastocyst formation rate is influenced by the age of the donor animal and the fresh cumulus cells have similar remodelling potential to that of fetal fibroblasts in term of blastocyst formation rate.


Assuntos
Senescência Celular , Desenvolvimento Embrionário , Técnicas de Transferência Nuclear , Animais , Ciclo Celular , Linhagem Celular , Núcleo Celular/fisiologia , Células do Cúmulo/fisiologia , Feminino , Fertilização in vitro , Feto/citologia , Fibroblastos/fisiologia , Oócitos/fisiologia , Ovinos , Técnicas de Cultura de Tecidos
12.
Cryobiology ; 60(2): 204-10, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19919830

RESUMO

This study was conducted to evaluate the effects of developmental stage of in vitro produced (IVP) ovine embryos and the type of vitrification procedure used on embryo cryotolerance. The IVP embryos were vitrified at five different developmental stages: 4-, 8- and 16-cell, morula, and blastocyst. For each stage, half of the embryos were vitrified in either 30 microl 3.4M glycerol+4.6M ethylene glycol in straw (method 1) or in <0.1 microl 2.7 M ethylene glycol+2.1 M Me(2)SO+0.5M sucrose placed on the inner surface of a straw (method 2) of vitrification solution, based on two different procedures. After warming embryo viability was determined by assessing the rates of re-expansion, survival, and blastocyst formation. The quality of surviving embryos was evaluated by their hatching rate and blastocyst cell numbers. In both vitrification methods, embryo survival progressively increased as the developmental stage progressed. In method 1 few of the early cleavage stage embryos (4-, 8- and 16-cell) could reach to the blastocyst stage following warming. There was no significant difference in blastocyst cell numbers (total, ICM, and trophectoderm cells) or hatching rate of blastocysts derived from vitrified embryos at different developmental stages. The number of dead cells in vitrified blastocysts in method 1 was higher than for non-vitrified blastocysts (P<0.05). The number of apoptotic cells in vitrified blastocysts was higher than for non-vitrified counterparts (P<0.05). In conclusion, both the developmental stage of IVP ovine embryos and the method of vitrification have a significant effect on the viability and developmental competence of sheep embryos.


Assuntos
Blastocisto , Criopreservação/métodos , Animais , Apoptose , Blastocisto/citologia , Contagem de Células , Fase de Clivagem do Zigoto/citologia , Técnicas de Cultura Embrionária , Desenvolvimento Embrionário , Feminino , Fertilização in vitro , Mórula/citologia , Ovinos
13.
Reprod Domest Anim ; 45(3): 530-6, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19032427

RESUMO

The objective of this study was to determine the effect of the presence of recombinant ovine growth hormone either alone or together with follicle stimulating hormone (FSH) during ovine oocyte in vitro maturation (IVM) on nuclear maturation and subsequent embryo development. Moreover, the effect of growth hormine (GH) on embryo development whether influenced by the presence of foetal bovine serum (FBS) was assessed. The abattoir-derived oocytes were randomly divided into four treatment groups and cultured in maturation medium supplemented with: (i) 0.05 IU/ml FSH; (ii) 300 ng/ml roGH; (iii) FSH + roGH; and (iv) no FSH and GH (control). The percentages of germinal vesicle-stage oocytes in GH-treated group after 8 h of culture was significantly higher than the FSH and FSH + GH groups and lower than control (22.4%, 8.7%, 9.1%, and 32% respectively). The percentage of MII-stage oocytes was significantly increased in the presence of GH after 16 and 24 h of culture compared to the control (44.7% and 83.1% vs 32.6% and 73.6% respectively). There was no significant synergism between GH and FSH in terms of nuclear maturation. The blastocyst rates in serum-supplemented groups were enhanced by the presence of FSH and GH compared to the control (35.4% and 31.3 vs 11.4% respectively). Compared with either GH or FSH alone, the subsequent embryo development (blastocyst rate), however, was negatively influenced by co-presence of both hormones (22.8%). In contrast, the corresponding values were not affected in the absence of serum. In conclusion, GH had positive effect on nuclear maturation of sheep oocytes. Moreover, the pattern of the effect of GH on embryo development was influenced by the presence of FBS during IVM.


Assuntos
Núcleo Celular/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Hormônio do Crescimento/administração & dosagem , Oócitos/ultraestrutura , Ovinos , Animais , Blastocisto/fisiologia , Bovinos , Núcleo Celular/fisiologia , Meios de Cultura , Interações Medicamentosas , Técnicas de Cultura Embrionária/veterinária , Feminino , Fertilização in vitro/veterinária , Sangue Fetal , Hormônio Foliculoestimulante/administração & dosagem , Oócitos/efeitos dos fármacos , Oócitos/crescimento & desenvolvimento , Proteínas Recombinantes/administração & dosagem , Soro
14.
Cryobiology ; 59(3): 285-90, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19716813

RESUMO

This study was designed to evaluate the effect of in vitro culture system on bovine blastocyst yield and quality after vitrification. In Experiment 1, IVM/IVF zygotes were allocated to three culture conditions: (I) Oviductal cells-SOF (OCM-SOF); (II) Oviductal cells-TCM (OCM-TCM); and (III) SOF for 8 days. There was no significant difference between blastocyst rates among groups. In Experiment 2, the IVP-blastocysts in three above culture conditions were vitrified within groups segregated according to age (Day 7 and 8) and blastocoelic cavity size (early and expanded blastocysts). A trend of higher survival rate was obtained in vitrified/warmed early blastocysts compared with expanded ones, so that the difference in OCM-TCM group was significant (P<0.001). Higher survival and hatching rates (P<0.001) were obtained in OCM-SOF and OCM-TCM groups (co-culture) compared with SOF group and the age of blastocyst had no effect on post-thaw survival and hatching rates. In Experiment 3, after staining of blastocysts, in fresh blastocysts the highest number of trophectoderm cells was observed in OCM-TCM group and the number of inner cell mass (ICM) was higher in co-culture groups than SOF group (P<0.001). In vitrified/warmed blastocysts the number of ICM and trophectoderm cells in co-culture groups was higher than SOF group (P<0.001) except for the ICM of expanded blastocysts. In conclusion, in our culture conditions, the blastocyst yield is not influenced by culture system, while the cryotolerance of IVP-blastocysts is positively influenced by the presence of somatic cells. Moreover, the expanded blastocysts are more susceptible to cryoinjury than early blastocysts.


Assuntos
Blastocisto/citologia , Criopreservação/veterinária , Técnicas de Cultura Embrionária/veterinária , Fertilização in vitro/veterinária , Animais , Bovinos , Sobrevivência Celular , Técnicas de Cocultura , Desenvolvimento Embrionário , Feminino
15.
Theriogenology ; 71(2): 342-8, 2009 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-18762332

RESUMO

The present study was conducted to determine the necessity for activation after intracytoplasmic sperm injection (ICSI) in sheep. The effect of chemical stimulation with either 5microM ionomycin (I) for 5min or ionomycin+2mM 6-dimethylaminopurine (6-DMAP) for 3h on the efficiency of ICSI, was compared in six experimental groups: (1) ICSI, (2) ICSI+I, (3) ICSI+I+6DMAP, (4) Sham, (5) Sham+I, and (6) parthenogenetics (Sham and parthenogenetic groups were used as controls). In the present study, ovine oocytes needed additional chemical stimulation, after conventional ICSI, to activate (female pronucleous formation) and to form zygotes with male and female pronuclei (2PN). The percentage of cleaved embryos obtained and developed to blastocyst stage was higher (P<0.001) for ICSI-derived zygotes, followed by activation (I and I+6DMAP; 18.2 and 22.5%, respectively) than ICSI and Sham injection without activation (3.0 and 0.0%, respectively). There was, however, no significant difference between activation protocols I or I+6DMAP. Furthermore, there was no significant difference among chemically activated, ICSI-derived zygotes in term of hatchability rate; however, the percentage was significantly higher in parthenogenetic and IVF groups than ICSI and Sham injection. In conclusion, neither sperm alone nor mechanical activation was sufficient for ovine oocyte activation and pronuclei formation. Therefore, in our study conditions for in vitro embryo development, chemical activation of oocytes must be considered an essential part of the ICSI procedure in sheep.


Assuntos
Ovinos/embriologia , Injeções de Esperma Intracitoplásmicas/veterinária , Animais , Feminino , Ionomicina/farmacologia , Masculino , Oócitos/efeitos dos fármacos , Oócitos/fisiologia
16.
Pak J Biol Sci ; 11(6): 938-41, 2008 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-18814661

RESUMO

Ovine embryos were produced by maturation, fertilization and in vitro culture (IVM/IVF/IVC) of oocytes collected from slaughtered prepubertal ewes. At 24 h post IVM, oocytes were fertilized with fresh semen collected from Lori-Bakhtiari breed at a concentration of 1.0 x l0(6) sperm mL(-1). The presumptive ova/embryos were transferred into the embryo culture medium at 22-24 h post IVF. Following 4 to 7 day in culture, embryos (at morula and blastocyst stage, respectively) were transferred surgically to the uterine horn of synchronized recipients. Pregnancy was diagnosed at day 30 by hormonal assay and at days 55 and 140 of gestation by ultrasonography and pregnancies were allowed to go to term. A total of nine ewes received 27 embryos (3 embryos/ewe). Five ewes received 15 embryos at morula stage and four ewes received 12 embryos at blastocyst stage. From those received morula stage embryos one was pregnant on day 30 (20%), though no pregnancy was diagnosed on each of days 55 and 140. While from those received blastocyst stage embryos, three ewes were pregnant on day 30 (75%) and two ewes (50%) remained pregnant on each of days 55 and 140. In conclusion, day 4 IVM-IVF morula stage embryos had a lower survival rate than did day 7 IVM-IVF blastocysts embryos, following transfer to the synchronized recipient ewes.


Assuntos
Transferência Embrionária/métodos , Fertilização in vitro/métodos , Animais , Blastocisto/citologia , Técnicas de Cultura Embrionária , Feminino , Mórula/citologia , Oócitos/citologia , Gravidez , Taxa de Gravidez , Prenhez , Ovinos , Fatores de Tempo
17.
Eur J Pharmacol ; 381(2-3): 129-33, 1999 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-10554880

RESUMO

The effect of GABA (gamma-aminobutyric acid system) receptor agonists and antagonists on naloxone-induced jumping in morphine-dependent mice was examined. Intraperitoneal (i.p.) or intracerebroventricular (i.c.v.) injection of different doses of the GABA(B) receptor agonist, baclofen (2.5, 5 and 10 mg/kg), reduced naloxone-induced jumping in morphine-dependent mice. The i.p. administration of the GABA(B) receptor antagonist, CGP35348 (P-[3-aminopropyl]-p-diethoxymethyl-phosphinic acid), but not the i.c.v. injection of the drug, increased naloxone-induced jumping. The antagonist also decreased the baclofen response. Administration of the GABA(A) receptor agonist, muscimol, but not the GABA(A) receptor antagonists bicuculline and picrotoxin, decreased the naloxone response in morphine-dependent animals. It is concluded that both GABA(A) and GABA(B) receptor subtypes may have an inhibitory influence on naloxone-induced withdrawal jumping in mice.


Assuntos
Comportamento Animal/efeitos dos fármacos , Dependência de Morfina/psicologia , Naloxona/farmacologia , Antagonistas de Entorpecentes/farmacologia , Síndrome de Abstinência a Substâncias/psicologia , Ácido gama-Aminobutírico/fisiologia , Animais , Baclofeno/administração & dosagem , Baclofeno/farmacologia , Bicuculina/administração & dosagem , Bicuculina/farmacologia , Agonistas GABAérgicos/administração & dosagem , Agonistas GABAérgicos/farmacologia , Antagonistas GABAérgicos/administração & dosagem , Antagonistas GABAérgicos/farmacologia , Agonistas de Receptores de GABA-A , Antagonistas de Receptores de GABA-A , Injeções Intraventriculares , Masculino , Camundongos , Muscimol/administração & dosagem , Muscimol/farmacologia , Compostos Organofosforados/administração & dosagem , Compostos Organofosforados/farmacologia , Picrotoxina/administração & dosagem , Picrotoxina/farmacologia
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