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1.
Zygote ; 31(2): 173-179, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36804925

RESUMO

Carvacrol (C10H14O), an efficient phenolic antioxidant substance for several cell types, may become a useful antioxidant for female germ cells and embryo culture. This study investigates the effects of carvacrol supplementation on bovine oocytes in in vitro maturation (IVM) and embryo production. In total, 1222 cumulus-oocyte complexes were cultured in TCM-199+ alone (control treatment) or supplemented with carvacrol at the concentrations of 3 µM (Carv-3), 12.5 µM (Carv-12.5), or 25 µM (Carv-25). After IVM, the oocytes were subjected to in vitro fertilization and embryo production, and the spent medium post-IVM was used for evaluating the levels of reactive oxygen species and the antioxidant capacity (2,2-diphenyl-1-picryl-hydrazyl-hydrate and 2,2'-azinobis-3-ethyl-benzothiozoline-6-sulphonic acid quantification). A greater (P < 0.05) antioxidant potential was observed in the spent medium of all carvacrol-treated groups compared with the control medium. Moreover, the addition of carvacrol to the maturation medium did not affect (P > 0.05) blastocyst production on days 7 and 10 of culture; however, the total number of cells per blastocyst was reduced (P < 0.05) in two carvacrol-treated groups (Carv-3 and Carv-25). In conclusion, carvacrol demonstrated a high antioxidant capacity in the spent medium after oocyte maturation; however, although embryo production was not affected, in general, carvacrol addition to IVM medium reduced the total number of cells per blastocyst. Therefore, due to the high antioxidant capacity of carvacrol, new experiments are warranted to investigate the beneficial effects of lower concentrations of carvacrol on embryo production in cattle and other species.


Assuntos
Antioxidantes , Técnicas de Maturação in Vitro de Oócitos , Bovinos , Feminino , Animais , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Técnicas de Maturação in Vitro de Oócitos/veterinária , Oogênese , Oócitos , Fertilização in vitro/veterinária , Blastocisto
2.
Int Endod J ; 53(10): 1327-1338, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32619274

RESUMO

AIM: To assess the impact of two root canal treatment protocols on the oral health-related quality of life (OHRQoL) of patients in need of root canal treatment on their anterior teeth. METHODOLOGY: The sample consisted of 120 participants (mean age: 34 years) enrolled in a pragmatic randomized clinical trial evaluating two root canal treatment protocols. Anterior teeth with nonvital pulps were allocated for root canal preparation with either hand files and filled with lateral compaction of gutta-percha (manual protocol) or canal preparation with a single file in a reciprocating movement and filled with a single cone technique (Reciproc protocol). OHRQoL data were assessed using the Oral Health Impact Profile instrument (OHIP-14), which was administered before the root canal intervention (baseline), and 6 and 12 months after treatment. Demographic and clinical characteristics of participants were collected at baseline. Data were analysed using bivariate analyses, Poisson univariate and multiple regression (α = 0.05). RESULTS: The drop-out rate from baseline was 27% and 28% at 6 and 12 months after treatment, respectively. Both root canal protocols significantly enhanced patients' OHRQoL, regardless of the follow-up time (P < 0.001). After 6 months, patients treated with the Reciproc protocol had significantly lower OHIP-14 overall scores (P = 0.030), as well as significantly lower scores for psychological discomfort (P = 0.031) and social disability (P = 0.013). After 12 months, no significant difference was observed between the two root canal protocols for OHIP-14 overall scores (P = 0.174). Either large or moderate effect sizes were observed for all domains and overall scores at both evaluation times, irrespective of the protocol. Low-income persons (RR = 2.03) and the Reciproc protocol (RR = 1.52) had a higher likelihood of a positive impact on OHRQoL 12 months after root canal treatment. CONCLUSIONS: The two root canal protocols improved the OHRQoL and differences in scores were observed only after 6 months with poorer OHRQoL for the manual protocol. After 12 months, patients with low-income status and treated with Reciproc were associated with a greater improvement in OHRQoL scores.


Assuntos
Qualidade de Vida , Materiais Restauradores do Canal Radicular , Adulto , Protocolos Clínicos , Cavidade Pulpar , Guta-Percha , Humanos , Obturação do Canal Radicular , Preparo de Canal Radicular , Tratamento do Canal Radicular
3.
Epidemiol Infect ; 146(10): 1293-1300, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29925445

RESUMO

Reducing the risk of human immunodeficiency virus type 1 (HIV-1) transmission is still a public health priority. The development of effective control strategies relies on the quantification of the effects of prophylactic and therapeutic measures in disease incidence. Although several assays can be used to estimate HIV incidence, these estimates are limited by the poor performance of these assays in distinguishing recent from long-standing infections. To address such limitation, we have developed an assay to titrate p24-specific IgG3 antibodies as a marker of recent infection. The assay is based on a recombinant p24 protein capable to detect total IgG antibodies in sera using a liquid micro array and enzyme-linked immunosorbent assay. Subsequently, the assay was optimised to detect and titrate anti-p24 IgG3 responses in a panel of sequential specimens from seroconverters over 24 months. The kinetics of p24-specific IgG3 titres revealed a transient peak in the 4 to 5-month period after seroconversion. It was followed by a sharp decline, allowing infections with less than 6 months to be distinguished from older ones. The developed assay exhibited a mean duration of recent infection of 144 days and a false-recent rate of ca. 14%. Our findings show that HIV-1 p24-specific IgG3 titres can be used as a tool to evaluate HIV incidence in serosurveys and to monitor the efficacy of vaccines and other transmission control strategies.


Assuntos
Anticorpos Antivirais/sangue , Proteína do Núcleo p24 do HIV/imunologia , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , HIV-1/imunologia , Imunoglobulina G/sangue , Biomarcadores/sangue , Ensaio de Imunoadsorção Enzimática , Humanos , Incidência , Cinética , Soroconversão , Estudos Soroepidemiológicos , Fatores de Tempo
4.
Reprod Fertil Dev ; 30(8): 1055-1065, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29332622

RESUMO

The aim of the present study was to compare fresh and vitrified goat ovarian tissue after autotransplantation and in vitro culture. Adult goats were completely ovariectomised and each ovarian pair was sliced and distributed among six different treatment groups: fresh control, fresh transplant, fresh culture, vitrified control, vitrified transplant and vitrified culture. Follicular morphology, development, growth, density, revascularisation and hormone production were evaluated in all groups. Three antral follicles (two in the fresh transplant and one in the vitrified transplant groups) were observed on the surface of the graft 90 days after transplantation. The percentage of morphologically normal follicles was similar in the fresh control, fresh transplant and vitrified transplant groups. The percentage of developing (transition, primary and secondary) follicles was higher after in vitro culture of fresh or vitrified tissue. Transplantation resulted in a lower follicle density. Serum oestradiol concentrations remained constant during the entire transplantation period. In contrast, progesterone production decreased significantly. Expression of CD31 mRNA was lower in fresh culture. In conclusion, restoration of goat ovarian function can be successfully achieved following transplantation of both fresh and vitrified goat ovarian tissue. However, transplantation induced higher follicle loss than in vitro culture.


Assuntos
Folículo Ovariano/crescimento & desenvolvimento , Animais , Criopreservação , Feminino , Cabras , Técnicas de Cultura de Tecidos , Transplante Heterotópico , Vitrificação
5.
Reprod Domest Anim ; 53(4): 880-888, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29604127

RESUMO

The aim was to verify the effect of follicle-stimulating hormone (FSH) supplementation to α-MEM+ or TCM199+ media on the in vitro development of ovarian preantral follicles (PFs) derived from collared peccaries. Ovaries (n = 5 pairs) were collected and divided into fragments destined to control group (non-cultured) or treatments that were cultured for 7 days. The PFs morphology, growth and activation were evaluated by classical histology. The immunohistochemistry markers Ag-NOR and PCNA were used for nuclear proliferation analysis, and the picrosirius red labelling was used for ovarian extracellular matrix (ECM) evaluation. After 7-day culture, only the TCM199+ treatment maintained the proportion of intact PFs similar to day 1 (63.2%), but no differences were found among treatments (p > .05). In addition, a significant increase in the growing follicles proportion was verified for all the treatments, indicating follicular activation (p > .05). By the Ag-NOR analysis, only the TCM199+/FSH maintained the nuclear proliferation similar to the first day (p > .05). The picrosirius red staining revealed that the ECM remained intact in all the treatments (p > .05). We suggest the use of TCM199+ medium supplemented of FSH for the in vitro development of peccaries PFs under 7-day culturing conditions.


Assuntos
Artiodáctilos/fisiologia , Hormônio Foliculoestimulante/farmacologia , Folículo Ovariano/efeitos dos fármacos , Técnicas de Cultura de Tecidos/veterinária , Animais , Feminino , Hormônio Foliculoestimulante/administração & dosagem , Folículo Ovariano/fisiologia
6.
Reprod Fertil Dev ; 29(6): 1144-1154, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27166082

RESUMO

The aim of the present study was to evaluate the effect of anti-Müllerian hormone (AMH), with and without FSH, on the in vitro development of isolated caprine preantral follicles, as well as follicular steroid production and mRNA levels of AMH, hormone receptors (AMH and FSH), CYP19A1 (cytochrome P450, family 19, subfamily A, polypeptide 1), CYP17 (cytochrome P450, family 17, subfamily A, polypeptide 1), HSD3B (3-beta-hydroxysteroid dehydrogenase) and Myc (myelocytomatosis oncogene). Isolated secondary follicles were cultured in minimum essential medium alpha (α-MEM+) alone or supplemented with 50ng mL-1 AMH and/or 100ng mL-1 FSH added sequentially on different days of culture. Follicles were cultured for a total of 18 days, with different media during the first (Days 0-9) and second (Days 10-18) halves of the culture period, resulting in six treatment groups, as follows: α-MEM+/α-MEM+, FSH/FSH, AMH/AMH, AMH+FSH/AMH+FSH, AMH/FSH, and FSH/AMH. Follicle development was evaluated on the basis of follicular growth, oocyte maturation and steroid secretion. There was a decrease in follicular growth rate in the AMH, AMH+FSH and AMH/FSH treatment groups compared with α-MEM+ and FSH treatment groups (P<0.05). However, the different culture conditions had no effect on rates of meiotic resumption and steroid secretion (P>0.05). Moreover, follicles cultured in the presence of FSH had lower levels of AMH receptor type II (AMHRII) mRNA compared with non-cultured control (freshly isolated follicles), and the AMH and AMH/FSH treatment groups. In conclusion, AMH reduces the follicular growth rate of isolated goat preantral follicles in vitro without affecting follicular survival.


Assuntos
Hormônio Antimülleriano/metabolismo , Hormônio Foliculoestimulante/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Oogênese , Folículo Ovariano/metabolismo , Receptores do FSH/agonistas , Receptores de Peptídeos/agonistas , Receptores de Fatores de Crescimento Transformadores beta/agonistas , Matadouros , Animais , Hormônio Antimülleriano/genética , Hormônio Antimülleriano/farmacologia , Brasil , Bovinos , Proliferação de Células/efeitos dos fármacos , Tamanho Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cruzamentos Genéticos , Estradiol/metabolismo , Feminino , Hormônio Foliculoestimulante/genética , Hormônio Foliculoestimulante/farmacologia , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Cabras , Humanos , Oogênese/efeitos dos fármacos , Folículo Ovariano/citologia , Folículo Ovariano/efeitos dos fármacos , Progesterona/metabolismo , Receptores do FSH/genética , Receptores do FSH/metabolismo , Receptores de Peptídeos/genética , Receptores de Peptídeos/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/genética , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologia , Testosterona/metabolismo , Técnicas de Cultura de Tecidos
7.
Cell Tissue Res ; 365(2): 415-24, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26975215

RESUMO

Our aim has been to evaluate the effect of cryoprotective agents (CPAs) on the exposure, vitrification (VIT), and in vitro culture (IVC) of ovarian tissue with regard to the expression and immunolocalization of aquaporins (AQPs) 3 and 9 in ovine preantral follicles. Tissues were treated as follows: Experiment I: (1) control (without exposure to CPAs), (2) e-EG (exposure to ethylene glycol), (3) er-EG (exposure to and removal of EG), (4) e-DMSO (exposure to dimethyl sulfoxide), (5) er-DMSO (exposure to and removal of DMSO), (6) e-EG+DMSO (exposure to EG+DMSO), (7) er-EG+DMSO (exposure to and removal of EG+DMSO); Experiment II: (1) control, (2) VIT, (3) IVC, (4) VIT-IVC. In Experiment I, following er-EG or er-DMSO, tissue showed the down-regulation (P < 0.05) of AQP3 mRNA. The mRNA transcript levels were reduced (P < 0.05) for AQP9 in tissue following er-EG+DMSO. Immunolocalization was positive for both proteins (AQP3 and AQP9) on ovine preantral follicles following all treatments, except in the e-EG+DMSO group. In Experiment II, the mRNA levels of AQP3 and AQP9 following VIT treatment were similar (P > 0.05) to that of the control group. Nevertheless, VIT-IVC treatment led to the down-regulation of mRNA of AQP3 and AQP9. Thus, AQP3 and AQP9 act in a mutually dependent way, maintaining the cell homeostasis that is essential for the ovary cryopreservation process. Furthermore, the changes in the expression profiles of mRNA and protein after culture are a strong indicator that in vitro conditions have to be strictly controlled to ensure follicle viability and functionality.


Assuntos
Aquaporinas/metabolismo , Crioprotetores/farmacologia , Ovário/metabolismo , Carneiro Doméstico/metabolismo , Técnicas de Cultura de Tecidos , Animais , Aquaporinas/genética , Feminino , Imuno-Histoquímica , Folículo Ovariano/citologia , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Vitrificação/efeitos dos fármacos
8.
Zygote ; 24(4): 568-77, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26464313

RESUMO

This study aimed to evaluate mRNA levels of angiotensin II (ANG II) receptors (AGTR1 and AGTR2) in caprine follicles and to investigate the influence of ANG II on the viability and in vitro growth of preantral follicles. Real-time polymerase chain reaction (PCR) was used to quantify AGTR1 and AGTR2 mRNA levels in the different follicular stages. For culture, caprine ovaries were collected, cut into 13 fragments and then either directly fixed for histological and ultrastructural analysis (fresh control) or placed in culture for 1 or 7 days in α-minumum essential medium plus (α-MEM+) with 0, 1, 5, 10, 50 or 100 ng/ml ANG II. Then, the fragments were destined to morphological, viability and ultrastructural analysis. The results showed that primordial follicles had higher levels of AGTR1 and AGTR2 mRNA than secondary follicles. Granulosa/theca cells from antral follicles had higher levels of AGTR1 mRNA than their respective cumulus-oocyte complex (COCs). After 7 days of culture, ANG II (10 or 50 ng/ml) maintained the percentages of normal follicles compared with α-MEM+. Fluorescence and ultrastructural microscopy confirmed follicular integrity in ANG II (10 ng/ml). In conclusion, a high expression of AGTR1 and AGTR2 is observed in primordial follicles. Granulosa/theca cells from antral follicles had higher levels of AGTR1 mRNA. Finally, 10 ng/ml ANG II maintained the viability of caprine preantral follicles after in vitro culture.


Assuntos
Expressão Gênica/genética , Folículo Ovariano/metabolismo , Ovário/metabolismo , Receptores de Angiotensina/genética , Angiotensina II/farmacologia , Animais , Sobrevivência Celular/genética , Relação Dose-Resposta a Droga , Feminino , Expressão Gênica/efeitos dos fármacos , Cabras , Microscopia Eletrônica , Microscopia de Fluorescência , Oócitos/metabolismo , Folículo Ovariano/citologia , Ovário/ultraestrutura , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Receptores de Angiotensina/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Técnicas de Cultura de Tecidos , Vasoconstritores/farmacologia
9.
Reprod Domest Anim ; 51(2): 212-9, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26834019

RESUMO

The aims of this study were to evaluate the localization, by immunohistochemistry, of the anti-Müllerian hormone (AMH) in goat ovaries and to investigate its effects on the in vitro survival and development of caprine pre-antral follicles enclosed in fragments of ovarian tissue. Pre-antral follicles were cultured in vitro for 1 or 7 days in α-MEM(+) in the absence or presence of kit ligand (KL; 50 ng/ml, positive control) or AMH (50 or 150 ng/ml). The results showed that AMH was localized in oocytes and granulosa cells from the primordial follicle to antral follicle stages. Addition of AMH maintained the percentage of developing follicles, similar to that in the uncultured control; however, the percentage of developing follicles was significantly lower than that in the cultured control and KL. Nonetheless, addition of AMH to the culture medium did not affect survival rates and follicular growth. In conclusion, this study demonstrated that the expression of AMH varies according to the compartment and stage of follicular development. Furthermore, AMH inhibits the activation of caprine primordial follicles.


Assuntos
Hormônio Antimülleriano/metabolismo , Cabras , Folículo Ovariano/metabolismo , Animais , Hormônio Antimülleriano/genética , Proliferação de Células , Fragmentação do DNA , Feminino , Oócitos/metabolismo , Transporte Proteico , Técnicas de Cultura de Tecidos
10.
Reprod Domest Anim ; 50(2): 177-185, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25545956

RESUMO

The aim of this study was to evaluate the influence of two vitrification techniques on the extra cellular matrix (ECM) and ovarian follicular development. The ovarian cortex was fragmented (9 mm(3)) and divided into six groups, viz. fresh control, cultured control, vitrified by the Ovarian Tissue Cryosystem (OTC) method, conventional solid surface vitrification (SSV) method, OTC/cultured and SSV/cultured. Follicles from all the fragments were analysed for morphology, development and viability. The ECM was evaluated based on the condition of collagen and reticular fibres and the immunolocalization of type I collagen and fibronectin. After 7 days of culture, the tissue vitrified by OTC revealed a higher percentage (p < 0.05) of morphologically normal (30.66%) and viable (60.00%) follicles when compared with those vitrified using the SSV technique (21.33% and 23.00%). In all the fragments cultured, regardless of the vitrification method, a significantly higher percentage of developing follicles was observed when compared with the non-cultured tissue. Analysis of the type I collagen showed increased immunostaining after the in vitro culture in the vitrified fragments. In conclusion, the OTC is better for preserving the follicular viability and morphology and maintaining the integrity of the extracellular matrix components of the ovine ovary.


Assuntos
Matriz Extracelular , Cabras , Folículo Ovariano/fisiologia , Vitrificação , Animais , Proliferação de Células/fisiologia , Criopreservação/veterinária , Feminino , Imuno-Histoquímica/veterinária , Folículo Ovariano/citologia , Técnicas de Cultura de Tecidos
11.
Reprod Fertil Dev ; 25(6): 955-65, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23050662

RESUMO

The aim of the present study was to evaluate the effects of growth differentiation factor 9 (GDF-9) and FSH on the in vitro development of caprine preantral follicles cultured for 16 days. Ovarian fragments were cultured in αMEM⁺ (α-minimum essential medium, pH 7.2-7.4, 10 µg mL⁻¹ insulin, 5.5 µg mL⁻¹ transferrin, 5.0 ng mL⁻¹ selenium, 2 mM glutamine, 2 mM hypoxanthine and 1.25 mg mL⁻¹ bovine serum albumin) in the absence or presence of 200 ng mL⁻¹ GDF-9 and/or 50 ng mL⁻¹ FSH added during the first (Days 0-8) and/or second (Days 8-16) half of the culture period. Non-cultured and cultured fragments were processed for histological and ultrastructural analyses. After 16 days, all treatments using GDF-9 or FSH showed higher rates of follicular survival compared with αMEM⁺ alone. Compared with non-cultured control, sequential culture media containing GDF-9 and/or FSH significantly increased the percentage of developing follicles and follicle diameter. Moreover, a progressive increase in oocyte diameter was observed only with sequential culture medium containing GDF-9 until Day 8 followed by FSH (GDF-9/FSH) in the second half of the culture period. After 16 days of culture, ultrastructural analysis confirmed the integrity of follicles cultured in the presence of GDF-9/FSH. In conclusion, a dynamic medium containing GDF-9 and FSH (GDF-9/FSH) maintained follicular integrity and promoted activation of primordial follicles and growth during long-term in vitro culture of goat preantral follicles.


Assuntos
Fármacos para a Fertilidade Feminina/farmacologia , Hormônio Foliculoestimulante/farmacologia , Cabras/fisiologia , Fator 9 de Diferenciação de Crescimento/farmacologia , Técnicas de Maturação in Vitro de Oócitos/veterinária , Folículo Ovariano/efeitos dos fármacos , Matadouros , Animais , Brasil , Bovinos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cruzamentos Genéticos , Feminino , Hormônio Foliculoestimulante/genética , Fator 9 de Diferenciação de Crescimento/genética , Humanos , Oócitos/efeitos dos fármacos , Oócitos/fisiologia , Oócitos/ultraestrutura , Oogênese/efeitos dos fármacos , Folículo Ovariano/fisiologia , Folículo Ovariano/ultraestrutura , Proteínas Recombinantes/farmacologia , Fatores de Tempo , Técnicas de Cultura de Tecidos/veterinária
12.
Zygote ; 21(2): 187-97, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22651979

RESUMO

Summary Nerve growth factor (NGF) is a prototype member of the neurotrophins family and has important functions in the maintenance of viability and proliferation of neuronal and non-neuronal cells, such as certain ovarian cells. The present review highlights the role of NGF and its receptors on ovarian follicle development. NGF initiates its multiple actions through binding to two classes of receptors: the high affinity receptor tyrosine kinase A (TrkA) and the low-affinity receptor p75. Different intracytoplasmic signalling pathways may be activated through binding to NGF due to variation in the receptors. The TrkA receptor activates predominantly phosphatidylinositol-3-kinase (PI3K) and mitogenic activated protein kinase (MAPK) to promote cell survival and proliferation. The activation of the phospholipase type Cγ (PLCγ) pathway, which results in the production of diacylglycerol (DAG) and inositol triphosphate (IP3), culminates in the release of calcium from the intracytoplasmic cellular stocks. However, the details of activation through p75 receptor are less well known. Expression of NGF and its receptors is localized in ovarian cells (oocyte, granulosa, theca and interstitial cells) from several species, which suggests that NGF and its receptors may regulate some ovarian functions such as follicular survival or development. Thus, the use of NGF in culture medium for ovarian follicles may be of critical importance for researchers who want to promote follicular development in vitro in the future.


Assuntos
Fator de Crescimento Neural/metabolismo , Folículo Ovariano/citologia , Receptores de Fator de Crescimento Neural/metabolismo , Animais , Feminino , Humanos , Folículo Ovariano/metabolismo
13.
Materials (Basel) ; 16(8)2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37109866

RESUMO

In this work, barium titanate powders were produced by sol-gel and sol-precipitation methods from metal alkoxides. In the sol-gel method, tetraisopropyl orthotitanate was mixed with 2-propanol, acetic acid and barium acetate, and the gel samples obtained were calcined at 600 °C, 800 °C and 1000 °C. Through the sol-precipitation method, tetraisopropyl orthotitanate was mixed with acetic acid and deionized water and precipitated by the addition of a concentrated solution of KOH. The products were calcined at various temperatures, and the microstructural and dielectric properties of the BaTiO3 prepared for the two processes were analyzed and compared. The results of these analyses allowed us to observe an increase in the tetragonal phase and the dielectric constant (15-50 at 20 kHz) with increasing temperatures in the samples produced by the sol-gel method, while the sample obtained by sol precipitation was cubic. The presence of BaCO3 is more evident in the sample produced by sol-precipitation, and the band gap of the products obtained did not show significant variation, changing the synthesis method (3.363-3.594 eV).

14.
Microbiol Res ; 273: 127420, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37270893

RESUMO

The genus Acinetobacter encompasses biotechnologically relevant species and nosocomial pathogens. In this study, nine isolates recovered from different oil reservoir samples showed the ability to grow with petroleum as the only carbon source and possessed the ability to emulsify kerosene. The whole genomes of the nine strains were sequenced and analyzed. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values of all strains were compared to the reference strains, and the results were below the reference values (<97.88 and 82, respectively), suggesting that the isolates belong to a new subspecies of Acinetobacter baumannii. The name Acinetobacter baumannii oleum ficedula is proposed. A comparison of the whole genome repertoire of 290 Acinetobacter species indicated that the strains in this study resemble non-pathogenic Acinetobacter strains. However, the new isolates resemble A. baumannii when comparing virulence factors. The isolates in this study carry many genes involved in hydrocarbon degradation, indicating the potential to degrade most toxic compounds listed by environmental regulatory agencies such as ATSDR, EPA, and CONAMA. In addition, despite the absence of known biosurfactant or bioemulsifier genes, the strains showed emulsifying activity, suggesting the presence of new pathways or genes related to this process. This study investigated the genomic, phenotypic, and biochemical features of the novel environmental subspecies A. baumannii oleum ficedula, revealing their potential to degrade hydrocarbons and to produce biosurfactants or bioemulsifiers. Applying these environmental subspecies in bioaugmentation strategies sheds light on future approaches to bioremediation. The study shows the importance of genomic analysis of environmental strains and their inclusion in metabolic pathways databases, highlighting unique enzymes/alternative pathways for consuming hazardous hydrocarbons.


Assuntos
Acinetobacter baumannii , Acinetobacter baumannii/genética , Acinetobacter baumannii/metabolismo , Campos de Petróleo e Gás , Hidrocarbonetos/metabolismo , Genômica , DNA
15.
Front Vet Sci ; 9: 822367, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35573397

RESUMO

This study evaluated the effects of different concentrations (10, 20, or 40 µM) of eugenol (EUG 10, EUG 20, or EUG 40), ascorbic acid (50 µg/mL; AA) or anethole (300 µg/mL; ANE 300) on the in-vitro survival and development of goat preantral follicles and oxidative stress in the cultured ovarian tissue. Ovarian fragments from five goats were cultured for 1 or 7 days in Alpha Minimum Essential Medium (α-MEM+) supplemented or not with AA, ANE 300, EUG 10, EUG 20 or EUG 40. On day 7 of culture, when compared to MEM, the addition of EUG 40 had increased the rate of follicular development, as observed by a decrease in the proportion of primordial follicles alongside with an increase in the rate of normally developing follicles. Furthermore, EUG 40 significantly increased both follicular and oocyte diameters. Subsequently, ovarian fragments from three goats were cultured for 1 or 7 days in α-MEM+ supplemented or not with AA, ANE 300 or EUG 40. All tested antioxidants, except ANE 300, were able to significantly decrease the levels of reactive oxygen species in the ovarian tissue, but EUG 40 could most efficiently neutralize free radicals. All ovarian tissues cultured in the presence of antioxidants, especially EUG 40, presented a significant decrease in H3K4me3 labeling, indicating a silencing of genes that play a role in the inhibition of follicular activation and apoptosis induction. When compared to cultured control tissues, both EUG 40 and ANE 300 significantly increased the intensity of calreticulin labeling in growing follicles. The mRNA relative expression of ERP29 and KDM3A was significantly increased when the culture medium was supplemented with EUG 40, indicating a response to ER stress experienced during culture. In conclusion, EUG 40 improved in-vitro follicle survival, activation and development and decreased ROS production, ER stress and histone lysine methylation in goat ovarian tissue.

16.
Theriogenology ; 188: 135-144, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35689943

RESUMO

Recent in vitro follicle culture (IVFC) studies in caprine have yielded lower maturation rates using late preantral follicles compared to early antral follicles. Thus, research focusing on developing stage-specific customized culture systems able to improve the efficiency of IVFC for late preantral follicles are warranted. This study aimed to compare the morphometric features, estradiol production, and gene expression between early antral caprine follicles produced in vitro and in vivo. In vitro-derived early antral follicles were produced after a 6-day in vitro culture of late preantral follicles, while in vivo-derived early antral follicles were yielded immediately after isolation from the ovaries; antral follicles were, thereafter, cultured for 18 days. In vitro-derived antral follicles were cultured either in a medium developed for preantral follicles (PF medium) or in a medium developed for antral follicles (AF medium). In vivo-derived early antral follicles, on the other hand, were cultured in AF medium (Control treatment). Results demonstrated that in vitro-derived antral follicles cultured in PF medium produced higher estradiol concentration, and m-RNA expression for matrix metalloproteinase-9 (MMP-9), and insulin receptor when compared to both in vitro- and in vivo-derived antral follicles cultured in AF medium. Remarkably, in vitro-derived antral follicles cultured in PF medium had similar MII and oocytes ≥110 µm rates compared with in vivo-derived antral follicles (Control treatment). In conclusion, when cultured in a single and appropriate medium (i.e., PF medium), in vitro-derived early antral follicles had comparable oocyte maturation rates to the in vivo-derived early antral follicles.


Assuntos
Cabras , Folículo Ovariano , Animais , Estradiol/metabolismo , Estradiol/farmacologia , Feminino , Hormônio Foliculoestimulante , Cabras/metabolismo , Técnicas de Maturação in Vitro de Oócitos/métodos , Técnicas de Maturação in Vitro de Oócitos/veterinária , Oócitos/metabolismo
17.
Theriogenology ; 192: 109-115, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36113319

RESUMO

This study investigates the impact of eugenol (EU) supplementation on bovine oocyte in vitro maturation (IVM) and antioxidant capacity, as well as in vitro embryo production and quality after conventional in vitro fertilization (IVF). A total of 1077 cumulus oocyte complexes were cultured in TCM-199+ without EU supplementation (control treatment) or supplemented with EU at the concentrations of 10 µM (EU-10), 20 µM (EU-20), or 40 µM (EU-40). After IVM, the oocytes were subjected to IVF and embryo culture. The addition of EU at 40 µM to the IVM medium improved (P < 0.05) the antioxidant capacity and cleavage rate when compared to the control treatment. Moreover, a positive correlation (r = 0.61, P < 0.03) was observed between cleavage rate and EU concentration. The addition of EU at concentrations of 10 and 20 µM decreased (P < 0.05) the calreticulin (CALR) levels in expanded blastocysts when compared to the control treatment and EU-40 treatment. However, the EU-10 and EU-20 treatments had a greater (P < 0.05) mean total cell number (TCN) per expanded blastocyst when compared to the control treatment and EU-40 treatment. In conclusion, the addition of EU to the enriched culture medium during IVM of bovine oocytes improved the antioxidant capacity of the spent medium, as well as the cleavage rate and embryonic quality (i.e., TCN/expanded blastocyst), and reduced the endoplasmic reticulum stress (i.e., CALR levels) in the embryos. Thus, we recommend enriching the IVM medium with 10 µM EU for in vitro bovine embryo production.


Assuntos
Eugenol , Técnicas de Maturação in Vitro de Oócitos , Animais , Antioxidantes/farmacologia , Blastocisto , Calreticulina , Bovinos , Contagem de Células/veterinária , Técnicas de Maturação in Vitro de Oócitos/veterinária
18.
Theriogenology ; 162: 105-110, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33453574

RESUMO

This study evaluated the effect of adding ultra-diluted and dynamized Arnica montana 6 cH, and its vehicle (0.3% ethanol) to the in vitro maturation (IVM) medium, in the absence (experiment 1) or presence (experiment 2) of heat stress (HS), on bovine oocyte maturation and in vitro embryo production (IVEP). In experiment 1 (n = 902 cumulus oocyte complexes, COCs), the treatments were 1) IVM medium (Control treatment), 2) IVM medium + 0.3% ethanol, and 3) IVM medium + Arnica montana 6 cH. In experiment 2 (n = 1064 COCs), the treatments were 1) IVM medium without HS, 2) IVM medium under HS, 3) IVM medium + ethanol under HS, and 4) IVM medium + Arnica montana under HS. In the absence of HS (experiment 1), the addition of Arnica montana to the IVM medium had a deleterious effect on the IVEP (cleavage and blastocyst rates) and the total cell number/blastocysts. On the other hand, ethanol (0.3%) increased IVEP in relation to the Control and Arnica montana treatments. However, in the presence of HS during IVM (experiment 2), the addition of ethanol or Arnica montana increased IVEP when compared to the HS treatment alone, and the Arnica montana treatment resulted in greater total cell number/blastocysts compared to the other treatments. In conclusion, this study showed for the first time that the negative or positive effect of Arnica montana 6 cH on IVEP depends on the culture condition (i.e., absence or presence of HS during IVM). On the other hand, ethanol showed beneficial and consistent results on IVEP regardless of exposure to HS.


Assuntos
Arnica , Técnicas de Maturação in Vitro de Oócitos , Animais , Blastocisto , Bovinos , Células do Cúmulo , Etanol/farmacologia , Feminino , Fertilização in vitro/veterinária , Resposta ao Choque Térmico , Técnicas de Maturação in Vitro de Oócitos/veterinária , Oócitos
19.
Cells Tissues Organs ; 191(5): 414-21, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20051667

RESUMO

The aim of this study was to evaluate the effect of vasoactive intestinal peptide (VIP)on the survival, activation and growth of goat preantral follicles after in vitro culture. The ovarian cortex was divided into small pieces and one fragment was immediately fixed (control). The remaining fragments were cultured in vitro for 1 or 7 days at 39 degrees C and 5% CO(2), in supplemented minimum essential medium (MEM(+)) with or without different concentrations of VIP (1, 10, 50, 100 or 200 ng/ml). Noncultured (fresh control) and cultured ovarian fragments were processed for histological analysis and transmission electron microscopy. Follicles were classified as primordial or developing, and as normal or degenerated. Our findings indicate that when compared with control, addition of all concentrations of VIP except 200 ng/ml resulted in similar percentages of normal preantral follicles after 1 and 7 days of culture. Culture of ovarian cortex tissue for 1 and 7 days increased the percentage of follicular activation in all treatments when compared with control, except with 1 ng/ml of VIP after 1 day. However, no difference was observed between VIP-treated and MEM(+)-treated follicles. In addition, after 7 days of culture, the highest follicular and oocyte diameters were observed in follicles cultured with 10 ng/ml VIP relative to MEM(+) alone. Transmission electron microscopy showed ultrastructural integrity of follicles after 7 days of culture in 10 ng/ml VIP. In conclusion, this study demonstrates that VIP maintains follicular integrity and stimulates caprine preantral follicle growth.


Assuntos
Folículo Ovariano/fisiologia , Peptídeo Intestinal Vasoativo/farmacologia , Animais , Meios de Cultura/farmacologia , Feminino , Cabras , Técnicas de Cultura de Tecidos , Peptídeo Intestinal Vasoativo/administração & dosagem
20.
Ecotoxicol Environ Saf ; 73(3): 320-5, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19910047

RESUMO

The aim of this study was to access the genotoxic potential of Extremoz Lake waters in Northeastern Brazilian coast, using the Allium cepa system, piscine micronucleus test and comet assay. In addition, heavy metal levels were quantified by atomic absorption flame spectrometry. The results of the A. cepa system showed significant changes in the frequency of chromosome aberrations and in the mitotic index compared to negative control. No significant changes were observed in micronuclei frequency in the erythrocytes of Oreochromis niloticus. The comet assay showed a statistically significant alteration in the level of DNA breaks of O. niloticus. Chemical analysis detected an increase in heavy metal levels in different sampling periods. These results point out a state of deterioration of water quality at Extremoz Lake, caused by heavy metal contamination and genotoxic activity. It is recommended to establish a monitoring program for the presence of genotoxic agents in this water lake.


Assuntos
Monitoramento Ambiental , Metais Pesados/toxicidade , Mutagênicos/toxicidade , Poluentes Químicos da Água/toxicidade , Poluição da Água/análise , Animais , Aberrações Cromossômicas/induzido quimicamente , Ensaio Cometa , Dano ao DNA , Peixes , Água Doce/química , Metais Pesados/classificação , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Testes para Micronúcleos , Mitose/efeitos dos fármacos , Índice Mitótico , Mutagênicos/classificação , Cebolas/efeitos dos fármacos , Cebolas/genética , Espectrofotometria Atômica , Poluentes Químicos da Água/classificação
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