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1.
Front Endocrinol (Lausanne) ; 15: 1415865, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38894739

RESUMO

Objectives: To explore the correlation between mitochondrial quantity and the blastocyst development timeline as well as their respective contributions to early pregnancy. Methods: A retrospective study was conducted using a dataset comprising 2,633 embryos that underwent preimplantation genetic testing for aneuploidy (PGT-A) between January 2016 and December 2023. The study was divided into three subsets to address distinct aspects: the representativeness of a single trophectoderm (TE) biopsy for mitochondrial quantity (n=43), the correlation between morphokinetic features and mitochondrial quantity (n=307), and the association analysis among mitochondrial quantity, blastocyst timeline factor, and reproductive outcomes (n=2,283). Distribution assessment of mitochondrial quantity across an individual blastocyst involved the identification within multiple biopsies and spent culture media. Timeline evaluation included correlating mitochondrial quantity with time-lapse datasets. Finally, multivariate logistic regression models, incorporating potential effectors alongside mitochondrial quantity, were employed to analyze their respective contributions to early pregnancy endpoints. Results: Of distribution assessment, mitochondrial quantity exhibited an even distribution across the entire trophectoderm (Spearman's ρ=0.82), while no detectable mtDNAs in the corresponding spent culture media. Then the timeline correlation study revealed significant association between mitochondrial quantity and blastocyst features of both the day of expanded blastocyst formation (95% Confidence intervals, CIs: 0.27~4.89, p=0.03) and the timing of expanded blastocyst formation (tEB) (95% CIs: -0.24~-0.01, p=0.04) in the regression model, indicating a strong dependency between mitochondrial quantity and the blastocyst development timeline. For the contribution to early pregnancy, multivariate logistic regression models showed that the day of expanded blastocyst formation contributed to four endpoints persistently: positive for HCG (odd ratio, OR: 0.71, p=0.006), gestational sac (OR: 0.78, p=0.04), fetal heartbeat (OR: 0.71, p=0.004), and progression to 14 weeks (OR: 0.69, p=0.002). Contrastingly, no notable correlation was observed between the mitochondrial quantity and these endpoints. Conclusions: Strong interaction was observed between mitochondrial quantity and the blastocyst timeline, particularly the timing of expanded blastocyst formation. It suggests that the primary determinant influencing pregnancy outcomes lies in the time-dependent parameter of blastocyst rather than in the specific mitochondrial quantity.


Assuntos
Blastocisto , Desenvolvimento Embrionário , Mitocôndrias , Resultado da Gravidez , Humanos , Feminino , Gravidez , Blastocisto/citologia , Blastocisto/fisiologia , Blastocisto/metabolismo , Estudos Retrospectivos , Mitocôndrias/metabolismo , Desenvolvimento Embrionário/fisiologia , Adulto , Técnicas de Cultura Embrionária , Transferência Embrionária/métodos , Diagnóstico Pré-Implantação/métodos , Fertilização in vitro/métodos
2.
Opt Lett ; 47(3): 561-564, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35103671

RESUMO

We demonstrate a Si/SiO/SiO2-based period-chirped guided mode resonance (GMR) filter to discriminate telecom o-band wavelengths by spatially resolved horizontal movement. Continuously period-chirped silicon gratings were fabricated by using a Lloyd's laser interferometer with a convex mirror. Due to the large waveguide effective index, the GMR filter can be realized with a short grating period, thus enabling a slow grating period transition along the sample position and high optical resolution in wavelength discrimination. Depositing a SiO/SiO2 stack on top of silicon gratings enables a narrowband GMR filter with a linewidth of 1-1.5 nm over a wavelength range of 1260-1360 nm. By using the chirped GMR filter as a dispersive device, the optical spectra of a near-infrared broadband light source are reconstructed. An optimized aspheric mirror is proposed to further improve the linearity of chirped gratings. Such a period-chirped GMR filter is promising for compact on-chip spectroscopy and sensing applications.

3.
FEBS Lett ; 593(14): 1698-1710, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31093969

RESUMO

The Drosophila transcription factor (TF) Zfh1 has distinct roles compared to the cell lineage-determining TFs in almost all mesoderm-derived tissues. Here, we link Zfh1 to the well-characterized mesodermal transcriptional network. We identify five enhancers integrating upstream regulatory inputs from mesodermal TFs and directing zfh1 expression in mesoderm. Most downstream Zfh1-target genes are co-bound by mesodermal TFs, suggesting that Zfh1 and mesodermal TFs act on the same sets of co-regulated genes during the development of certain mesodermal tissues. Furthermore, we demonstrate that Zfh1 is critical for the expression of a hemocyte marker gene peroxidasin and helps restrict the activity of a hemocyte-specific enhancer of serpent to hemocyte-deriving head mesoderm, suggesting a potential role of Zfh1 in hemocyte development.


Assuntos
Proteínas de Drosophila/metabolismo , Redes Reguladoras de Genes , Genômica , Mesoderma/metabolismo , Proteínas Repressoras/metabolismo , Animais , Drosophila melanogaster/embriologia , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Hemócitos/metabolismo
4.
Opt Express ; 26(21): 27515-27527, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30469817

RESUMO

In this work we introduce a tunable GMR filter based on continuously period-chirped (ΔP = 130 nm) gratings using a Ta2O5 waveguide layer with graded thickness (ΔT = 36 nm). The structure of the gradient-period grating is defined using a modified Lloyd's mirror interferometer with a convex mirror, and Ta2O5 film used for the gradient is deposited using masked e-beam evaporation. The as-realized chirped GMR filter provides sharp transmission dips at resonant wavelengths with a filter bandwidth of approximately 4.2 nm and 0.78 nm when respectively applied to TE and TM polarized light under normal incidence. Gradually sweeping the chirped GMR filter makes it possible to monotonically sweep through resonant wavelengths from 500 to 700 nm, while maintaining stable filter bandwidth and transmission intensity. The optical spectrum of the incoming light can then be loyally reconstructed accordingly. We successfully demonstrate the spectrum reconstruction of a white light emitting diode and a dual-peak laser beam using the proposed chirped GMR filter as a dispersive device.

5.
Hepatology ; 68(3): 815-826, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29350774

RESUMO

Chronic hepatitis B virus (HBV) infection is the major cause of hepatocellular carcinoma (HCC). The pre-S2 mutant large HBV surface antigen (LHBS) is highly associated with HCC. This study analyzed the expression of the large form of surface protein in tumors and evaluated the LHBS with mutations within the pre-S2 region as a high-risk recurrence marker in HCC patients after curative hepatic resection. By analyses using immunohistochemical staining (n = 12) and western blotting (n = 22), the HBV surface protein, which is mainly comprised of the major form of HBV surface antigen, was greatly diminished in the tumors. However, LHBS was not significantly decreased in tumorous regions, suggesting that LHBS maintains its expression in cancer development. A cohort of 175 patients with HBV-related HCC who underwent curative hepatic resection was analyzed for pre-S gene mutations using Pre-S Gene Chip. Results of the multivariate regression analysis showed that the serum pre-S2 mutant level and the American Joint Committee on Cancer stage were the two main independent high-risk factors for recurrence. A Cox proportional hazards analysis also revealed a prediction model, which indicated the recurrence-free survival rate along with the time after surgery; this was developed and further validated in an independent HCC cohort. Receiver operating characteristic curve analysis revealed that the model showed close sensitivities in the main and validation cohorts (area under the curve values, 0.741 and 0.704, respectively). Conclusion: Unlike the major HBV surface antigen, LHBS is mostly expressed in the tumorous regions of HBV-induced HCC, indicating that it plays a unique role in tumor progression; the relative level of pre-S2 mutant in serum is, independently of tumor stage, an important high-risk marker for HCC recurrence after primary hepatic resection. (Hepatology 2018).


Assuntos
Carcinoma Hepatocelular/sangue , Antígenos de Superfície da Hepatite B/sangue , Neoplasias Hepáticas/sangue , Recidiva Local de Neoplasia/sangue , Precursores de Proteínas/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/sangue , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/cirurgia , Estudos de Coortes , Feminino , Antígenos de Superfície da Hepatite B/genética , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/genética , Precursores de Proteínas/genética , Adulto Jovem
6.
Opt Lett ; 42(22): 4768-4771, 2017 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-29140365

RESUMO

Graphene oxide (GO) ultrathin film can be wafer-scale deposited by spin coating, can be patterned by laser interference lithography and oxygen plasma etching, can be thinned atomically (0.26 nm/min) and oxidized by ozone treatment, and is a relatively transparent and low-refractive-index material compared to pristine graphene. All those unique properties prompt us to realize a low-loss (∼5 dB/cm), high-extinction-ratio (19 dB), and narrowband (0.425 nm) GO/silicon hybrid waveguide Bragg reflector by transferring 7-nm-thick GO gratings (n=1.58) atop a silicon strip waveguide. Unlike a sidewall-corrugated strip waveguide Bragg reflector that generally exhibits distorted corrugation profiles and is sensitive to fabrication errors, the as-realized GO-grating-covered strip waveguide Bragg reflector exhibits a stable reflecting wavelength and controllable reflection bandwidth that can be well predicted by numerical simulations.

7.
PLoS One ; 10(4): e0124418, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25898207

RESUMO

Microvascular complications eventually affect nearly all patients with diabetes. Advanced glycation end-products (AGEs) resulting from hyperglycemia are a complex and heterogeneous group of compounds that accumulate in the plasma and tissues in diabetic patients. They are responsible for both endothelial dysfunction and diabetic vasculopathy. The aim of this study was to investigate the cytotoxicity of AGEs on pancreatic islet microvascular endothelial cells. The mechanism underlying the apoptotic effect of AGEs in pancreatic islet endothelial cell line MS1 was explored. The results showed that AGEs significantly decreased MS1 cell viability and induced MS1 cell apoptosis in a dose-dependent manner. AGEs dose-dependently increased the expressions of cleaved caspase-3, and cleaved poly (ADP-ribose) polymerase in MS1 cells. Treatment of MS1 cells with AGEs also resulted in increased nuclear factor (NF)-κB-p65 phosphorylation and cyclooxygenase (COX)-2 expression. However, AGEs did not affect the expressions of endoplasmic reticulum (ER) stress-related molecules in MS1 cells. Pretreatment with NS398 (a COX-2 inhibitor) to inhibit prostaglandin E2 (PGE2) production reversed the induction of cleaved caspase-3, cleaved PARP, and MS1 cell viability. Moreover, AGEs significantly increased the receptor for AGEs (RAGE) protein expression in MS1 cells, which could be reversed by RAGE neutralizing antibody. RAGE Neutralizing antibody could also reverse the induction of cleaved caspase-3 and cleaved PARP and decreased cell viability induced by AGEs. These results implicate the involvement of NF-κB-activated COX-2/PGE2 up-regulation in AGEs/RAGE-induced islet endothelial cell apoptosis and cytotoxicity. These findings may provide insight into the pathological processes within the pancreatic islet microvasculature induced by AGEs accumulation.


Assuntos
Apoptose , Ciclo-Oxigenase 2/metabolismo , Dinoprostona/biossíntese , Células Endoteliais/fisiologia , Produtos Finais de Glicação Avançada/fisiologia , Animais , Linhagem Celular , Sobrevivência Celular , Angiopatias Diabéticas/metabolismo , Angiopatias Diabéticas/patologia , Estresse do Retículo Endoplasmático , Ativação Enzimática , Ilhotas Pancreáticas/irrigação sanguínea , Ilhotas Pancreáticas/patologia , Camundongos , NF-kappa B/metabolismo , Regulação para Cima
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