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1.
Cureus ; 16(6): e62571, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39027776

RESUMO

Introduction Assisted reproductive technologies (ART) rely on endometrial receptivity (ER) for successful embryo implantation. This study aimed to compare the impact of different progesterone administration routes on ER assessed using optimal time for endometrial receptivity analysis (OpERA) and clinical outcomes in ART cycles. Methods A retrospective cohort analysis was conducted on 281 infertile women who underwent in vitro fertilization (IVF). Patients were stratified based on progesterone administration routes: oral and vaginal progesterone (Group 1) vs. intramuscular progesterone (Group 2). OpERA was performed on 257 patients to assess ER. Clinical outcomes, including biochemical pregnancy rate (BPR), clinical pregnancy rate (CPR), implantation rate (IR), and abortion rate (AR), were compared between the groups. Results OpERA results showed no significant differences between Group 1 and Group 2 in receptive (51.2% vs. 52.0%, p = 0.857), pre-receptive (44.1% vs. 44.6%, p = 0.933), or post-receptive (4.7% vs. 3.1%, p = 0.496) states. Clinical outcomes, including BPR (59.9% vs. 60.9%, p = 0.903), CPR (50.0% vs. 56.5%, p = 0.463), IR (52.5% vs. 55.3%, p = 0.748), and AR (44.3% vs. 45.6%, p = 0.882), did not significantly differ between the groups. Conclusion Progesterone administration routes did not significantly affect ER or clinical outcomes, highlighting the need to prioritize understanding and enhancing ER instead of solely focusing on progesterone delivery methods. Identifying molecular pathways or biomarkers could improve receptivity and optimize ART, ultimately improving pregnancy outcomes.

2.
Cureus ; 16(2): e54940, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38544578

RESUMO

Background Infertility remains a significant global challenge, and recurrent implantation failure (RIF) poses a considerable concern in assisted reproductive technology. Understanding the factors contributing to implantation failure is essential for developing accurate diagnostic tools and treatment strategies. Endometrial receptivity (ER) during the window of implantation is crucial for successful embryo implantation in in vitro fertilization (IVF) procedures. Molecular-based endometrial receptivity analysis and next-generation sequencing provide insights into ER, but there is a lack of research on these in the Indian population, particularly in patients with RIF. This retrospective cohort study evaluates the effectiveness of Optimal Timing for Endometrial Receptivity Analysis (OpERA)-guided personalized embryo transfer (pET) in Indian patients with a history of RIF. Methodology The study includes 158 female patients with a history of failed embryo transfers who underwent OpERA testing before frozen embryo transfer. Patients were categorized based on the number of previous failed transfers. OpERA outcomes were assessed, and clinical outcomes were compared between groups undergoing preimplantation genetic testing for aneuploidy (PGT-A) with and without OpERA. Endometrial preparation involved hormone replacement therapy, and OpERA testing was performed at the Neuberg Centre for Genomic Medicine using RNA extraction, cDNA conversion, and sequencing. Results OpERA outcomes showed no significant differences in receptive rates among patient groups. Group 3, with three or more failed transfers, exhibited significantly higher biochemical pregnancy rates (BPRs), clinical pregnancy rates (CPRs), and abortion rates (ARs) compared to Groups 1 and 2. OpERA with PGT-A showed significantly higher BPR, implantation rate, CPR, and lower AR compared to OpERA without PGT-A. Conclusions OpERA-guided pET, especially with PGT-A, demonstrated improved pregnancy outcomes, particularly in patients with a history of RIF. The study emphasizes the importance of OpERA in determining optimal transfer timing, moving beyond the traditional reliance on embryo quality alone. OpERA presents promise in predicting pregnancy outcomes for Indian patients with previous IVF failures. The integration of OpERA and PGT-A represents a significant advancement in personalized reproductive medicine, offering new hope for individuals grappling with infertility complexities.

3.
Braz J Microbiol ; 55(1): 235-244, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38150151

RESUMO

Cordyceps militaris is a fungus with numerous therapeutic properties that has gained worldwide popularity due to its potential health benefits. The fruiting body of this mushroom is highly expensive and takes a longer time to produce, making mycelial a sustainable and cost-effective alternative. The study investigates and optimizes cultural and nutritional conditions to maximize mycelial biomass. The initial optimization was done by the conventional single-factor approach, followed by Plackett-Burman design to screen the most significant variables, with yeast extract, temperature, and glucose being the most significant, contributing 11.58%, 49.74%, and 27.98%, respectively, in mycelial biomass production. These variables were then optimized using response surface methodology (RSM) based on central composite design (CCD). The study observed that temperature and glucose had the highest impact on mycelial biomass, with p-values of 0.0128 and 0.0191, respectively. Under the optimized conditions, temperature 20 °C, glucose 2.5% (w/v), and yeast extract 0.8% (w/v), the maximal yield of mycelial biomass reached 547 ± 2.09 mg/100 mL, which was 1.95-fold higher than the yield in the basal medium. These findings suggest that optimizing the cultural and nutritional conditions can enhance mycelial biomass production of Cordyceps militaris, offering a sustainable and cost-effective source of this valuable fungus.


Assuntos
Cordyceps , Nitrogênio , Carbono , Biomassa , Glucose
4.
Chem Sci ; 10(25): 6354-6361, 2019 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-31341591

RESUMO

The magnetic properties of 3d monometallic complexes can be tuned through geometric control, owing to their synthetic accessibility and relative structural simplicity. Monodentate ligands offer great potential for fine-tuning the coordination environment to engineer both the axial and rhombic zero-field splitting (ZFS) parameters. In [CoCl3(DABCO)(HDABCO)] (1), the trigonal bipyramidal Co(ii) centre has two bulky axial ligands and three equatorial chloride ligands. An in-depth experimental and theoretical study of 1 reveals a large easy-plane magnetic anisotropy (+ve D) with a negligible rhombic zero-field splitting (E) due to the strict axial symmetry imposed by the C 3 symmetric ligand and trigonal space group. The large easy-plane magnetic anisotropy (D = +44.5 cm-1) is directly deduced using high-field EPR and frequency-domain magnetic resonance (FDMR) studies. Ab initio calculations reveal a large positive contribution to the D term arising from ground state/excited state mixing of the 4E'' states at ∼4085 cm-1 and a minor contribution from the spin-flip transition as well. The nature of the slow relaxation in 1 is elucidated through analysis of the rates of relaxation of magnetisation, taking into account Raman and direct spin-lattice relaxation processes and Quantum Tunnelling of the Magnetisation (QTM). The terms relating to the direct process and QTM were found based on the fit of the field-dependence of τ at 2 K. Subsequently, these were used as fixed parameters in the fit of the temperature-dependence of τ to obtain the Raman terms. This experimental-theoretical investigation provides further insight into the power of FDMR and ab initio methods for the thorough investigation of magnetic anisotropy. Thus, these results contribute to design criteria for high magnetic anisotropy systems.

5.
Dalton Trans ; 47(28): 9237-9240, 2018 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-29953164

RESUMO

We report a trinuclear mixed-valence {CoIICoIII2} complex, where the CoII centre adopts a trigonal bipyramidal geometry, leading to a large, easy-plane magnetic anisotropy and field-induced slow magnetic relaxation with a Raman-like relaxation process.

6.
Chem Sci ; 6(12): 6823-6828, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28757973

RESUMO

Monometallic complexes based on 3d transition metal ions in certain axial coordination environments can exhibit appreciably enhanced magnetic anisotropy, important for memory applications, due to stabilisation of an unquenched orbital moment. For high-spin trigonal bipyramidal Ni(ii), if competing structural distortions can be minimised, this may result in an axial anisotropy that is at least an order of magnitude stronger than found for orbitally non-degenerate octahedral complexes. Broadband, high-field EPR studies of [Ni(MDABCO)2Cl3]ClO4 (1) confirm an unprecedented axial magnetic anisotropy, which pushes the limits of the familiar spin-only description. Crucially, compared to complexes with multidentate ligands that encapsulate the metal ion, we see only a very small degree of axial symmetry breaking. 1 displays field-induced slow magnetic relaxation, which is rare for monometallic Ni(ii) complexes due to efficient spin-lattice and quantum tunnelling relaxation pathways.

7.
ACS Nano ; 8(8): 7923-9, 2014 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-25007391

RESUMO

We report a room temperature study on the electrical response of field-effect transistors (FETs) based on few-layered MoSe2, grown by a chemical vapor transport technique, mechanically exfoliated onto SiO2. In contrast to previous reports on MoSe2 FETs electrically contacted with Ni, MoSe2 FETs electrically contacted with Ti display ambipolar behavior with current on to off ratios up to 10(6) for both hole and electron channels when applying a small excitation voltage. A rather small hysteresis is observed when sweeping the back-gate voltage between positive and negative values, indicating the near absence of charge "puddles". For both channels the Hall effect indicates Hall mobilities µH ≃ 250 cm(2)/(V s), which are comparable to the corresponding field-effect mobilities, i.e., µFE ∼ 150 to 200 cm(2)/(V s) evaluated through the conventional two-terminal field-effect configuration. Therefore, our results suggest that MoSe2 could be a good candidate for p-n junctions composed of a single atomic layer and for low-power, complementary logic applications.

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