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1.
Zygote ; 28(3): 233-240, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32151301

RESUMO

This study aimed to: (i) characterize cultured granulosa cells (GCs) from different follicle sizes morphologically and molecularly; and (ii) select a suitable model according to follicular size that maintained GC function during culture. Buffalo ovaries were collected from a slaughterhouse and follicles were classified morphologically into: first group ≤ 4 mm, second group 5-8 mm, third group 9-15 mm and fourth group 16-20 mm diameter. GC pellets were divided into two portions. The first portion served as the control fresh pellet, and the secondwas used for 1 week for GC culture. Total RNA was isolated, and qRT-PCR was performed to test for follicle-stimulating hormone receptor (FSHR), cytochrome P450 19 (CYP19), luteinizing hormone/choriogonadotropin receptor (LHCGR), proliferating cell nuclear antigen (PCNA), apoptosis-related cysteine peptidase (CASP3), anti-Müllerian hormone (AMH), and phospholipase A2 group III (PLA2G3) mRNAs. Estradiol (E2) and progesterone (P4) levels in the culture supernatant and in follicular fluids were measured using enzyme-linked immunosorbent assay (ELISA). Basic DMEM-F12 medium maintained the morphological appearance of cultured GCs. The relative abundance of FSHR, CYP19, and LHCGR mRNAs was 0.001 ≤ P ≤ 0.01 and decreased at the end of culture compared with the fresh pellet. There was a fine balance between expression patterns of the proliferation marker gene (PCNA) and the proapoptotic marker gene (CASP3). AMH mRNA was significantly increased (P < 0.001) in cultured GCs from small follicles, while cultured GCs from other three categories (5-8 mm, 9-15 mm and 16-20 mm) showed a clear reduction (P < 0.001). Interestingly, the relative abundance of PLA2G3 mRNA was significantly (P < 0.001) increased in all cultured GCs. E2 and P4 concentrations were significantly (P < 0.001) decreased in all cultured groups. Primary cultured GCs from small follicles could be a good model for better understanding follicular development in Egyptian buffaloes.


Assuntos
Perfilação da Expressão Gênica/métodos , Células da Granulosa/metabolismo , Folículo Ovariano/metabolismo , RNA Mensageiro/genética , Animais , Aromatase/genética , Búfalos , Caspase 3/genética , Tamanho Celular , Células Cultivadas , Estradiol/metabolismo , Feminino , Líquido Folicular/metabolismo , Células da Granulosa/citologia , Folículo Ovariano/citologia , Progesterona/metabolismo , Antígeno Nuclear de Célula em Proliferação/genética , Receptores do FSH/genética , Receptores do LH/genética
2.
Sci Rep ; 14(1): 7912, 2024 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575715

RESUMO

Recent advancements in the field of biomedical engineering have underscored the pivotal role of biodegradable materials in addressing the challenges associated with tissue regeneration therapies. The spectrum of biodegradable materials presently encompasses ceramics, polymers, metals, and composites, each offering distinct advantages for the replacement or repair of compromised human tissues. Despite their utility, these biomaterials are not devoid of limitations, with issues such as suboptimal tissue integration, potential cytotoxicity, and mechanical mismatch (stress shielding) emerging as significant concerns. To mitigate these drawbacks, our research collective has embarked on the development of protein-based composite materials, showcasing enhanced biodegradability and biocompatibility. This study is dedicated to the elaboration and characterization of an innovative suture fabricated from human serum albumin through an extrusion methodology. Employing a suite of analytical techniques-namely tensile testing, scanning electron microscopy (SEM), and thermal gravimetric analysis (TGA)-we endeavored to elucidate the physicochemical attributes of the engineered suture. Additionally, the investigation extends to assessing the influence of integrating biodegradable organic modifiers on the suture's mechanical performance. Preliminary tensile testing has delineated the mechanical profile of the Filament Suture (FS), delineating tensile strengths spanning 1.3 to 9.616 MPa and elongation at break percentages ranging from 11.5 to 146.64%. These findings illuminate the mechanical versatility of the suture, hinting at its applicability across a broad spectrum of medical interventions. Subsequent analyses via SEM and TGA are anticipated to further delineate the suture's morphological features and thermal resilience, thereby enriching our comprehension of its overall performance characteristics. Moreover, the investigation delves into the ramifications of incorporating biodegradable organic constituents on the suture's mechanical integrity. Collectively, the study not only sheds light on the mechanical and thermal dynamics of a novel suture material derived from human serum albumin but also explores the prospective enhancements afforded by the amalgamation of biodegradable organic compounds, thereby broadening the horizon for future biomedical applications.


Assuntos
Materiais Biocompatíveis , Engenharia Tecidual , Humanos , Estudos Prospectivos , Materiais Biocompatíveis/química , Suturas , Albuminas , Albumina Sérica Humana
3.
Nanomaterials (Basel) ; 13(2)2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36678046

RESUMO

Biomedical applications, such as artificial implants, are very significant for the disabled due to their usage in orthopedics. Nevertheless, available materials in such applications have insufficient mechanical and tribological properties. The current study investigated the mechanical and tribological properties of a biomedical metallic material, magnesium (Mg), after incorporating titanium dioxide nanofibers (TiO2) with different loading fractions. The TiO2 nanofibers were synthesized using the electrospinning technique. The ball-milling technique was utilized to ensure the homogenous distribution of TiO2 nanofibers inside the Mg matrix. Then, samples of the mixed powder with different loading fractions of TiO2 nanofibers, 0, 1, 3, 5, and 10 wt.%, were fabricated using a high-frequency induction heat sintering technique. The physicomechanical and tribological properties of the produced Mg/TiO2 nanocomposites were evaluated experimentally. Results showed an enhancement in mechanical properties and wear resistance accompanied by an increase in the weight fraction of TiO2 nanofibers up to 5%. A finite element model was built to assess the load-carrying capacity of the Mg/TiO2 composite to estimate different contact stresses during the frictional process. The finite element results showed an agreement with the experimental results.

4.
Int J Gynaecol Obstet ; 161(3): 760-768, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36572053

RESUMO

OBJECTIVE: To establish a prognostic model for endometrial cancer (EC) that individualizes a risk and management plan per patient and disease characteristics. METHODS: A multicenter retrospective study conducted in nine European gynecologic cancer centers. Women with confirmed EC between January 2008 to December 2015 were included. Demographics, disease characteristics, management, and follow-up information were collected. Cancer-specific survival (CSS) and disease-free survival (DFS) at 3 and 5 years comprise the primary outcomes of the study. Machine learning algorithms were applied to patient and disease characteristics. Model I: pretreatment model. Calculated probability was added to management variables (model II: treatment model), and the second calculated probability was added to perioperative and postoperative variables (model III). RESULTS: Of 1150 women, 1144 were eligible for 3-year survival analysis and 860 for 5-year survival analysis. Model I, II, and III accuracies of prediction of 5-year CSS were 84.88%/85.47% (in train and test sets), 85.47%/84.88%, and 87.35%/86.05%, respectively. Model I predicted 3-year CSS at an accuracy of 91.34%/87.02%. Accuracies of models I, II, and III in predicting 5-year DFS were 74.63%/76.72%, 77.03%/76.72%, and 80.61%/77.78%, respectively. CONCLUSION: The Endometrial Cancer Individualized Scoring System (ECISS) is a novel machine learning tool assessing patient-specific survival probability with high accuracy.


Assuntos
Neoplasias do Endométrio , Feminino , Humanos , Estudos Retrospectivos , Prognóstico , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/terapia , Intervalo Livre de Doença , Aprendizado de Máquina
5.
J Matern Fetal Neonatal Med ; 35(25): 5087-5098, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33627019

RESUMO

Rectovaginal colonization with group B streptococcus (GBS) is commonly encountered in pregnancy. GBS is the most common cause of early onset neonatal sepsis, which is associated with 12% case-fatality rate. Although screening protocols and prophylactic treatment are readily available worldwide, practice in low-resource countries is challenged by lack of awareness and limited implementation of these protocols. In addition, antibiotic susceptibility pattern may vary globally owing to different regulations of antibiotic prescription or prevalence of certain bacterial serotypes. This guideline appraises current evidence on screening and management of GBS colonization in pregnancy particularly in low-resource settings.


Assuntos
Complicações Infecciosas na Gravidez , Infecções Estreptocócicas , Gravidez , Recém-Nascido , Feminino , Humanos , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/tratamento farmacológico , Complicações Infecciosas na Gravidez/prevenção & controle , Antibioticoprofilaxia/métodos , Streptococcus agalactiae , Infecções Estreptocócicas/diagnóstico , Infecções Estreptocócicas/tratamento farmacológico , Infecções Estreptocócicas/prevenção & controle , Antibacterianos/uso terapêutico , Educação de Pós-Graduação
6.
Polymers (Basel) ; 13(24)2021 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-34960870

RESUMO

This study is focuses on the investigation of the effect of using TiO2 short nanofibers as a reinforcement of an Al matrix on the corrosion characteristics of the produced nanocomposites. The TiO2 ceramic nanofibers used were synthesized via electrospinning by sol-gel process, then calcinated at a high temperature to evaporate the residual polymers. The fabricated nanocomposites contain 0, 1, 3 and 5 wt.% of synthesized ceramic nanofibers (TiO2). Powder mixtures were mixed for 1 h via high-energy ball milling in a vacuum atmosphere before being inductively sintered through a high-frequency induction furnace at 560 °C for 6 min. The microstructure of the fabricated samples was studied by optical microscope and field emission scanning electron microscope (FESEM) before and after corrosion studies. Corrosion behavior of the sintered samples was evaluated by both electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization techniques (PPT) in 3.5% NaCl solution for one hour and 24-h immersion times. The results show that even though the percentage of ceramic nanofibers added negatively control corrosion resistance, it is still possible to increase resistance against corrosion for the fabricated nanocomposite by more than 75% in the longer exposure time periods.

7.
Polymers (Basel) ; 13(24)2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34960957

RESUMO

Epoxy is considered to be the most popular polymer and is widely used in various engineering applications. However, environmental considerations require natural materials-based epoxy. This necessity results in further utilization of natural materials as a natural reinforcement for different types of composites. Corn cob is an example of a natural material that can be considered as an agricultural waste. The objective of the present work is to improve the economic feasibility of corn cob by converting the original corn cob material into powder to be utilized in reinforcing epoxy-based composites. In the experiment, the corn cob was crushed and ground using a grain miller before it was characterized by scanning electron microscopy (SEM). The corn cob powder was added to the epoxy with different weight fractions (2, 4, 6, 8, 10 wt%). In order to prevent corn cob powder agglomeration and ensure homogeneous distribution of the reinforcement inside the epoxy, the ultrasonic technique and a mechanical stirrer were used. Then, the composite's chemical compositions were evaluated using X-ray diffraction (XRD). The mechanical experiments showed an improvement in the Young's modulus and compressive yield strength of the epoxy composites, increasing corn cob up to 8 wt% by 21.26% and 22.22%, respectively. Furthermore, tribological tests revealed that reinforcing epoxy with 8 wt% corn cob can decrease the coefficient of friction by 35% and increase wear resistance by 4.8%. A finite element model for the frictional process was constructed to identify different contact stresses and evaluate the load-carrying capacity of the epoxy composites. The finite element model showed agreement with the experimental results. An epoxy containing 8 wt% corn cob demonstrated the optimal mechanical and tribological properties. The rubbed surfaces were investigated by SEM to identify the wear mechanism of different composites.

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