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1.
Inorg Chem ; 62(35): 14422-14430, 2023 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-37607342

RESUMEN

Metal ion-doped zero-dimensional halide perovskites provide good platforms to generate broadband emission and explore the fundamental dynamics of emission regulations. Recently, Sb3+-doped zero-dimensional halide perovskites have attracted considerable attention for the high quantum yield of yellow emission; however, the triplet state recombination is activated and the singlet state emission is usually absent. Herein, we fabricate an Sb3+-doped zero-dimensional [(CH3)4N]2SnCl6 perovskite that can induce singlet and triplet emission. Density functional theory calculation shows that there are some overlaps between the highest occupied molecular orbitals and the lowest unoccupied molecular orbitals, which may induce a large energy separation between the lowest excited triplet states (T1) and the lowest excited singlet states (S1) [ΔE(S1 - T1)], impeding all the carriers' transfer from the singlet state to the triplet state. As a result, the reserved singlet emission together with the triplet emission can be regulated by excitation wavelength in situ. In addition, different Bi3+ ratios are co-doped into Sb3+@[(CH3)4N]2SnCl6, resulting in a photoluminescence ex situ regulation. Single-phase white light LED and optical anti-counterfeiting are developed further.

2.
Mar Drugs ; 21(2)2023 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-36827152

RESUMEN

Tachypleus tridentatus (T. tridentatus) is a marine animal and traditional Chinese medicine. T. tridentatus plasma is a valuable resource for important medical and health-based functions. In this experiment, in order to evaluate the effect and mechanism of T. tridentatus plasma with respect to the promotion of bone tissue growth in rats, the processes of ultrafiltration and mass spectrometry were first used to separate and identify the components of T. tridentatus plasma. Then, a comparison of the effects of the T. tridentatus plasma samples, which each possessed different molecular weights, regarding the growth of the long bones of rats was conducted. Finally, transcriptomics, proteomics, and bioinformatics were all used to analyze the biological functions and related signaling pathways of the T. tridentatus plasma in order to promote rat bone growth. The results showed that the contents of amino acid residues in peptides are related to the growth promotion that was contained in the 10-30 kDa plasma group. Moreover, the T. tridentatus plasma samples were found to be higher in this respect than those in the whole plasma group. In addition, the 10-30 kDa plasma group could significantly promote bone growth activity in rats. The proteomic analysis showed that the proteins that were differentially expressed in the 10-30 kDa plasma group were mainly enriched in the PI3K-AKT signal pathway. Our study suggested that the T. tridentatus plasma possesses promising potential for the purposes of clinical use, whereby it can serve the role of a growth-promoting agent.


Asunto(s)
Cangrejos Herradura , Fosfatidilinositol 3-Quinasas , Animales , Ratas , Cangrejos Herradura/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteómica , Péptidos/metabolismo , Perfilación de la Expresión Génica
3.
Arch Gynecol Obstet ; 308(3): 787-795, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-36602559

RESUMEN

BACKGROUND: This paper evaluated the clinical utility of massively parallel sequencing-based non-invasive prenatal testing (NIPT) for detecting trisomy 21 (T21), T18, T13, sex chromosome aneuploidies (SCA), and rare chromosome aneuploidies (RCA) among the data collected by a clinical laboratory in southern China. METHODS: In a 3-year period between January 2017 and December 2019, over 40,000 pregnant women underwent NIPT clinical screening test for fetal T21, T18, T13, SCA, and RCA in our laboratory. NIPT samples were processed using the NextSeq CN500 platform. The positive results were confirmed by karyotyping, and chromosomal microarray analysis (CMA) or copy number variants (CNV) sequencing. Details of the pregnancy outcomes were collected via telephone interview. RESULTS: NIPT results were available for 41,819 cases; 691 positive cases were reported. The overall sensitivity for detection of T21, T18, T13, SCA, and RCA was 99.21, 100.00, 100.00, 98.55, and 100.00%, and the specificity was 99.95, 99.94, 99.98, 99.69, and 99.92%, respectively. The positive predictive values (PPVs) for detection of T21, T18, T13, SCA, and RCA were 85.62, 45.24, 40.00, 34.17, and 13.51%, respectively, and those for detection of 45,X, 47,XXY, 47,XXX, 47,XYY, and 46,XY(delX) 20.00, 59.18, 28.95, 61.54, and 25.00%, respectively. Regarding pregnancy outcomes, 92.38% of the pregnancies with confirmed aneuploidies were terminated, and 91.20% of those identified as having a false-positive result were carried to term. Among 252 unconfirmed cases, 24.60% of the pregnancies were terminated and 38.10% carried to term, while 37.30% declined interview. CONCLUSIONS: NIPT is widely used to screen fetal aneuploidies based on its high sensitivity and specificity. However, in this study, the PPVs of NIPT in terms of detecting T18, T13, XO, XXX and RCA were < 50%. In addition, more than one-third of NIPT-positive women did not accept invasive prenatal diagnosis. Confirmatory diagnosis is strongly recommended for women with positive NIPT outcomes before any further decision is made.


Asunto(s)
Síndrome de Down , Mujeres Embarazadas , Femenino , Embarazo , Humanos , Laboratorios Clínicos , Diagnóstico Prenatal/métodos , Síndrome de Down/diagnóstico , Aneuploidia , Resultado del Embarazo
4.
BMC Pregnancy Childbirth ; 22(1): 698, 2022 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-36088304

RESUMEN

BACKGROUND: Fetal macrosomia is common occurrence in pregnancy, which is associated with several adverse prognosis both of maternal and neonatal. While, the accuracy of prediction of fetal macrosomia is poor. The aim of this study was to develop a reliable noninvasive prediction classifier of fetal macrosomia. METHODS: A total of 3600 samples of routine noninvasive prenatal testing (NIPT) data at 12+ 0-27+ 6 weeks of gestation, which were subjected to low-coverage whole-genome sequencing of maternal plasma cell-free DNA (cfDNA), were collected from three independent hospitals. We identified set of genes with significant differential coverages by comparing the promoter profiling between macrosomia cases and controls. We selected genes to develop classifier for noninvasive predicting, by using support vector machine (SVM) and logistic regression models, respectively. The performance of each classifier was evaluated by area under the curve (AUC) analysis. RESULTS: According to the available follow-up results, 162 fetal macrosomia pregnancies and 648 matched controls were included. A total of 1086 genes with significantly differential promoter profiling were found between pregnancies with macrosomia and controls (p < 0.05). With the AUC as a reference,the classifier based on SVM (CMA-A2) had the best performance, with an AUC of 0.8256 (95% CI: 0.7927-0.8586). CONCLUSIONS: Our study provides that assessing the risk of fetal macrosomia by whole-genome promoter nucleosome profiling of maternal plasma cfDNA based on low-coverage next-generation sequencing is feasible.


Asunto(s)
Ácidos Nucleicos Libres de Células , Macrosomía Fetal , Estudios de Casos y Controles , China , Femenino , Macrosomía Fetal/diagnóstico , Macrosomía Fetal/genética , Humanos , Recién Nacido , Nucleosomas , Embarazo , Estudios Retrospectivos
5.
Angew Chem Int Ed Engl ; 61(51): e202210975, 2022 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-36271496

RESUMEN

Triplet exciton-based long-lived phosphorescence is severely limited by the thermal quenching at high temperature. Herein, we propose a novel strategy based on the energy transfer from triplet self-trapped excitons to Mn2+ dopants in solution-processed perovskite CsCdCl3 . It is found the Mn2+ doped hexagonal phase CsCdCl3 could simultaneously exhibit high emission efficiency (81.5 %) and long afterglow duration time (150 s). Besides, the afterglow emission exhibits anti-thermal quenching from 300 to 400 K. In-depth charge-carrier dynamics studies and density functional theory (DFT) calculation provide unambiguous evidence that carrier detrapping from trap states (mainly induced by Cl vacancy) to localized emission centers ([MnCl6 ]4- ) is responsible for the afterglow emission with anti-thermal quenching. Enlightened by the present results, we demonstrate the application of the developed materials for optical storage and logic operation applications.

6.
Angew Chem Int Ed Engl ; 60(36): 19653-19659, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34151496

RESUMEN

For display applications, it is highly desirable to obtain tunable red/green/blue emission. However, lead-free perovskite nanocrystals (NCs) generally exhibit broadband emission with poor color purity. Herein, we developed a unique phase transition strategy to engineer the emission color of lead-free cesium manganese bromides NCs and we can achieve a tunable red/green/blue emission with high color purity in these NCs. Such phase transition can be triggered by isopropanol: from one dimensional (1D) CsMnBr3 NCs (red-color emission) to zero dimensional (0D) Cs3 MnBr5 NCs (green-color emission). Furthermore, in a humid environment both 1D CsMnBr3 NCs and 0D Cs3 MnBr5 NCs can be transformed into 0D Cs2 MnBr4 ⋅2 H2 O NCs (blue-color emission). Cs2 MnBr4 ⋅2 H2 O NCs could inversely transform into the mixture of CsMnBr3 and Cs3 MnBr5 phase during the thermal annealing dehydration step. Our work highlights the tunable optical properties in single component NCs via phase engineering and provides a new avenue for future endeavors in light-emitting devices.

7.
Sensors (Basel) ; 20(21)2020 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-33182360

RESUMEN

As overhead contact (OC) is an essential part of power supply systems in high-speed railways, it is necessary to regularly inspect and repair abnormal OC components. Relative to manual inspection, applying LiDAR (light detection and ranging) to OC inspection can improve efficiency, accuracy, and safety, but it faces challenges to efficiently and effectively segment LiDAR point cloud data and identify catenary components. Recent deep learning-based recognition methods are rarely employed to recognize OC components, because they have high computational complexity, while their accuracy needs to be improved. To track these problems, we first propose a lightweight model, RobotNet, with depthwise and pointwise convolutions and an attention module to recognize the point cloud. Second, we optimize RobotNet to accelerate its recognition speed on embedded devices using an existing compilation tool. Third, we design software to facilitate the visualization of point cloud data. Our software can not only display a large amount of point cloud data, but also visualize the details of OC components. Extensive experiments demonstrate that RobotNet recognizes OC components more accurately and efficiently than others. The inference speed of the optimized RobotNet increases by an order of magnitude. RobotNet has lower computational complexity than other studies. The visualization results also show that our recognition method is effective.

8.
Angew Chem Int Ed Engl ; 59(49): 21925-21929, 2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-32827320

RESUMEN

Thermally activated delayed fluorescence (TADF) is generally observed in solid-state organic molecules or metal-organic complexes. However, TADF in all-inorganic colloidal nanocrystals (NCs) is rare. Herein, we report the first colloidal synthesis of an air-stable all-inorganic lead-free Cs2 ZrCl6 perovskite NCs. The Cs2 ZrCl6 NCs exhibit long-lived triplet excited state (138.2 µs), and feature high photoluminescence (PL) quantum efficiency (QY=60.37 %) due to TADF mechanism. The emission color can be easily tuned from blue to green by synthesizing the mixed-halide Cs2 ZrBrx Cl6-x (0≤x≤1.5) NCs. Femtosecond transient absorption and temperature dependent PL measurements are performed to clarify the emission mechanism. In addition, Bi3+ ions are successfully doped into Cs2 ZrCl6 NCs, which further extends the PL properties. This work not only develops a new lead-free halide perovskite NCs for potential optoelectronic applications, but also offers unique strategies for developing new inorganic phosphors.

9.
BMC Med Genet ; 19(1): 66, 2018 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-29720104

RESUMEN

BACKGROUND: Peutz-Jeghers Syndrome (PJS) is a hereditary cancer predisposing syndrome caused by autosomal dominant mutations in the serine/threonine kinase 11 (STK11) gene and is associated with decreased life expectancy. Many families experience a poorer quality of life due to the psychological burden associated with the carrier status of their child. Therefore early genetic testing and confirmation of the diagnosis is important for patients' psychological status, as well as for clinical management, genetic counseling and possible prenatal family planning. METHODS: In this study, peripheral blood genomic DNA samples from a Chinese PJS family with a high cancer risk were examined for STK11 mutations using Sanger sequencing and MLPA analysis. Furthermore, prenatal PJS testing from transabdominal chorionic villi sample was performed in one female member of the family. This family was followed up for three years. RESULTS: In this family, the STK11 exon 1 deletion (c.-1114-?_290 +?del) was predicted to affect the kinase domain of the protein and co-segregated with the disease phenotype. The same mutation was detected in the fetus and genetic sequencing and MLPA of the infant's DNA and the pigmentation on his lips confirmed the result of prenatal testing. To the best of our knowledge, this is the first report on PJS prenatal diagnosis of a PJS family in China. CONCLUSIONS: An accurate and convenient PJS prenatal testing provides an opportunity for affected families to focus on polyp-related symptoms and cancer prevention and may be helpful for couples in family planning decision-making.


Asunto(s)
Pueblo Asiatico/genética , Síndrome de Peutz-Jeghers/genética , Diagnóstico Prenatal/métodos , Proteínas Serina-Treonina Quinasas/genética , Quinasas de la Proteína-Quinasa Activada por el AMP , Femenino , Pruebas Genéticas/métodos , Humanos , Linaje , Embarazo , Análisis de Secuencia de ADN , Eliminación de Secuencia
10.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 32(4): 515-9, 2015 Aug.
Artículo en Zh | MEDLINE | ID: mdl-26252098

RESUMEN

OBJECTIVE: To detect copy number changes of α-globin gene, and analyze molecular mechanism of the impacts of fetal hemoglobin (HbF) levels for α-globin gene copy numbers loss or increase. METHODS: A total of 15 cases with combined increased levels of fetal hemoglobin with ß-thalassemia were collected. Firstly, three common α-thalassemia deletions were validated by Gap-PCR. Secondly, the largest deletions of the ß-globin gene cluster were detected by multiplex ligation-dependent probe amplification (MLPA). RESULTS: Among the 15 cases, there was 1 case with duplication of the α-globin gene cluster, 3 cases of SEA heterozygote deletion of the α-globin gene, 1 cases of α 3.7 deletion heterozygote of the α-globin gene, 1 case of alpha 4.2 deletion homozygote of the α-globin gene, 1 case of deletion homozygote in the like α-globin gene. A compound heterozygous for SEA and α 3.7 of the α-globin gene was also detected. However, 7 cases showed no copy numbers loss and increase of the the α-globin gene cluster. CONCLUSION: Additional α-globin gene can produce excessive α-chain, which can aggravate imbalance for α and ß-chain, and cause clinical symptoms in patients with ß-thalassemia. Yet, copy number loss or mutation in α-globin gene will cause a milder clinical phenotype.


Asunto(s)
Variaciones en el Número de Copia de ADN , Hemoglobina Fetal/metabolismo , Globinas alfa/genética , Talasemia beta/genética , Adulto , Pueblo Asiatico/genética , China , Femenino , Humanos , Lactante , Masculino , Mutación , Linaje , Talasemia beta/metabolismo
11.
Artículo en Inglés | MEDLINE | ID: mdl-38651210

RESUMEN

OBJECTIVE: To evaluate non-invasive prenatal testing (NIPT) and expanded non-invasive prenatal testing (NIPT-plus) for detecting aneuploidies at different sequencing depths and assess Z-score accuracy in predicting trisomies 21, 18, 13, 45X, and 47XXX. METHODS: Pregnancies with positive NIPT or NIPT-plus results detected at the prenatal diagnosis center of Nanfang Hospital were included in this retrospective study, between January 2017 and December 2022. Invasive prenatal diagnostic results were collected. Logistic regression analyses were used to study the relationship between Z-score and positive predictive value (PPV). Optimal cut-off values were obtained based on receiver operating characteristic analysis, and PPVs were calculated in different groups. RESULTS: We evaluated 1348 pregnant women with positive results, including 930 reported by NIPT and 418 reported by NIPT-plus. NIPT reported significantly more rare chromosomal aneuploidies (RCAs), and NIPT-plus had a significantly higher PPV for trisomy 21 (T21). Logistic regression analyses showed a significant association (P < 0.001) between Z-score and PPVs for T21 and trisomy 18 (T18). A linear relationship was observed between fetal fraction (FF) and Z-values in the true positive cases of T21 and T18.The high Z-score group had significantly higher PPVs than the low Z-score group for T21, T18, trisomy 13, and 47XXX, but not for 45X. CONCLUSION: The Z-score is helpful in assessing NIPT or NIPT-plus results. Therefore, we suggest including the Z-score and FF in the results. By combining the Z-score, FF, and maternal age, clinicians can interpret NIPT results more accurately and improve personal counsel to reduce patients' anxiety.

12.
Opt Express ; 21(3): 3501-15, 2013 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-23481808

RESUMEN

We investigate the entanglement generation between two nitrogen-vacancy (NV) centers in diamond nanocrystal coupled to a high-Q counterpropagating twin whispering-gallery modes (WGMs) of a microtoroidal resonator. For looking into the degree and dynamics of the entanglement, we calculate the concurrence using the microscopic master equation approach. The influences of the coupling strength between the WGMs (or the size of the two spherical NV centers), the distance between two NV centers, the frequency detuning between the NV center and microresonator, and the initial state of the system on the dynamics of concurrence are discussed in detail. It is found that the maximum entanglement between the two NV centers can be created by properly adjusting these controllable system parameters. Our results may provide further insight into future solid-state cavity quantum electrodynamics (CQED) system for quantum information engineering.


Asunto(s)
Modelos Químicos , Nitrógeno/química , Teoría Cuántica , Resonancia por Plasmón de Superficie/instrumentación , Transductores , Simulación por Computador , Diseño de Equipo , Análisis de Falla de Equipo , Miniaturización
13.
J Phys Chem Lett ; 14(43): 9646-9654, 2023 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-37870498

RESUMEN

Lead-free halide perovskites are promising materials for solar energy applications. However, their efficiency is hindered by poor light absorption in the visible-near-infrared region. Herein, we introduce vanadium (V) with low-lying ground/excited-state energy levels to form two types of stable lead-free V-based perovskite (Cs2NaVCl6 and Cs3V2Cl9) colloidal nanocrystals (NCs) with strong light absorption covering the ultraviolet to near-infrared region. We find the absorption can be further enhanced by structural regulation, in which the zero-dimensional (0D) Cs3V2Cl9 NCs show stronger and red-shifted (up to 1400 nm) light absorption compared to the three-dimensional Cs2NaVCl6 NCs. In 0D Cs3V2Cl9 NCs, [V2Cl9]3- dimers play a vital role in governing strong visible-near-infrared light absorption. We demonstrated their application for photocatalytic CO2 reduction. Our work sheds light on the structure-property relationship governing the absorption behavior, providing a novel route for tuning the light absorption ability of lead-free halide perovskites.

14.
J Cancer Res Clin Oncol ; 149(20): 18215-18240, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38078963

RESUMEN

INTRODUCTION: Tumor immunotherapy has recently emerged as a crucial focal point in oncology treatment research. Among tumor immunotherapy approaches, tumor immune checkpoint inhibitors (ICIs) have attracted substantial attention in clinical research. However, this treatment modality has benefitted only a limited number of patients. We conducted a meta-analysis of various biomarkers to decipher their prognostic implications in patients with head and neck squamous cell carcinoma (HNSCC) who are treated with ICIs, and thus identify predictive markers with practical clinical relevance. METHODS: A systematic search of electronic databases was conducted to identify clinical studies that examined the correlation between biomarkers and treatment outcomes in the HNSCC patients. The included articles were screened and analyzed to extract data regarding overall survival (OS) and progression-free survival (PFS). RESULTS: The relationship between the biomarkers included in the summary and prognosis was as follows: HPV positivity was associated with improved OS (HR = 0.76, 95% CI = 0.58-1.99), PFS (HR = 1.16, 95% CI = 0.81-1.67), and response (OR = 1.67, 95% CI = 1.37-2.99). PD-L1 positivity was associated with OS (HR = 0.71, 95% CI = 0.59-0.85), PFS (HR = 0.56 95% CI = 0.43-0.73), and response (OR = 2.16, 95% CI = 1.51-3.10). Neither HPV positivity nor PD-L1 positivity was associated with DCR. The following markers were collected for OS and PFS data and were associated with longer OS: lower Glasgow prognostic score (GPS/mGPS) grading, lower PS grading, high body mass index (BMI), low neutrophil-to-lymphocyte ratio (NLR), low platelet-to-lymphocyte ratio (PLR), high albumin (Alb), low lactate dehydrogenase (LDH). Factors associated with better PFS were lower GPS/mGPS grading, lower PS grading, high BMI, low NLR, high absolute lymphocyte count, and low LDH. Hyperprogressive disease was associated with worse OS and PFS. Fewer clinical studies have been completed on the tumor microenvironment and hypoxia, microsatellite instability/DNA mismatch repair, and microbiome and systematic analysis is difficult. CONCLUSION: In our meta-analysis, different immune checkpoint factors were associated with different prognoses in HNSCC patients receiving immunotherapy. HPV, PD-L1, BMI, Alb, HPD, PS, GPS/mGPS, LDH, NLR, and PLR predicted the ICI outcome in HNSCC patients.


Asunto(s)
Neoplasias de Cabeza y Cuello , Infecciones por Papillomavirus , Humanos , Pronóstico , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Antígeno B7-H1/análisis , Carcinoma de Células Escamosas de Cabeza y Cuello/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Biomarcadores , Microambiente Tumoral
15.
Front Plant Sci ; 14: 1280382, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37900744

RESUMEN

Introduction: Intercropping and straw mulching are sustainable agricultural practices that can positively affect crop growth and development, especially together. Methods: A split-plot experimental design was used to investigate the effects of intercropping and straw mulching on crop growth, crop yield, nitrogen uptake, and photosynthetic characteristics. The main plot focused on three planting patterns: soybean monoculture (S), maize monoculture (M), and maize/soybean intercropping (I). The subplot structure consisted of four levels of straw mulching (0, 4.8, 7.2, 9.6 t ha-1). Results: Interaction and variance analyses showed that straw mulching, intercropping, and their interaction had significant effects on plant height, stem diameter, leaf area index, chlorophyll content, nitrogen uptake, photosynthetic characteristics, and crop yield. Based on two-year averages for maize and soybean, the net photosynthetic rate (Pn) was up to 51.6% higher, stomatal conductance (Sc) was up to 44.0% higher, transpiration rate (Tr) was up to 46.6% higher, and intercellular carbon dioxide concentration (Ci) was up to 25.7% lower relative to no mulching. The maximum increases of Pn, Sc, and Tr of intercropped maize were 15.48%, 17.28%, and 23.94%, respectively, and the maximum Ci was 17.75% lower than that of monoculture maize. The maximum increase of Pn, Sc, and Tr of monoculture soybean was 24.58%, 16.90%, and 17.91%, respectively, and the maximum Ci was 13.85% lower than that of intercropped soybean. The nitrogen uptake of maize and soybean in the mulching treatment was 24.3% higher than that in the non-mulching treatment; the nitrogen uptake of intercropped maize was 34.2% higher than that of monoculture maize, and the nitrogen uptake of monoculture soybean was 15.0% higher than that of intercropped soybean. The yield of maize and soybean in the mulching treatment was 66.6% higher than that in the non-mulching treatment, the maize yield under intercropping was 15.4% higher than that under monoculture, and the yield of monoculture soybean was 9.03% higher than that of intercropped soybean. Discussion: The growth index and photosynthesis of crops are important parts of yield formation. The results of this study confirmed that straw mulching, intercropping, and their interaction can ultimately increase crop yield by improving crop growth, nitrogen uptake, and photosynthesis. This result can be used as the theoretical basis for the combined application of these measures in agriculture.

16.
J Phys Chem Lett ; 14(34): 7665-7671, 2023 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-37603899

RESUMEN

Low dimensional perovskite-inspired materials with self-tapped exciton (STE) emission have stimulated a surge of cutting-edge research in optoelectronics. Despite numerous efforts on developing versatile low-dimensional perovskite-inspired materials with efficient STE emissions, there is little emphasis on the intrinsic dynamics of STE-based broad emission in these materials. Here, we investigated the excited state dynamics in zero-dimensional (0D) Cs2ZrCl6 nanocrystals (NCs) with efficient blue STE emission. By using femtosecond transient absorption (fs-TA) spectroscopy, the ultrafast STE formation process within 400 fs is directly observed. Then, the formed STEs relax to an intermediate STE state with a lifetime of ∼180 ps before reaching the emissive STE state with a lifetime of ∼15 µs. Our work offers a comprehensive and precise dynamic picture of STE emission in low-dimensional metal halides and sheds light on extending their potential applications.

17.
Ginekol Pol ; 93(9): 716-720, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35315016

RESUMEN

OBJECTIVES: To explore the feasibility of clinical application of non-invasive prenatal screening to detect aneuploidy diseases. MATERIAL AND METHODS: A total of 14,574 singleton pregnant women who underwent Non-invasive prenatal testing (NIPT) in the Southern Hospital from 2015 to June 2017 were selected, and 6471 pregnant women with twin pregnancy who underwent NIPT in the laboratory of Bei Rui He Kang Southern Hospital from June 2016 to October 2017 were included in this study. We analyzed NIPT screening efficiency (sensitivity, specificity) in twin pregnancies and singleton pregnancies, compared the positive detection rate of NIPT in patients with or without clinical symptoms. All NIPT high-risk results were validated by karyotyping, which were further verified by the follow-up physical examination of the neonatal. RESULTS: A total of 68 cases of twin pregnancy abnormalities were detected by NIPT, including 18 cases of trisomy 21, 6 cases of trisomy 18, 1 case of trisomy 13, 39 cases of Spinocerebellar ataxias (SCAs), and 4 cases of other chromosomal abnormalities. The sensitivity for trisomy 21, 18, and 13 and sex chromosome abnormality was 100%; the specificity for trisomy 21, 18, and 13 and sex chromosome abnormality was 99.97%, 99.95%, 99.97%, and 99.91% respectively. The screening efficiency was similar to that of singleton pregnancy, indicating that the NIPT technology in our laboratory for screening for aneuploidy diseases in twin pregnancy has reached the accuracy level of singleton pregnancy screening. There was a statistical difference between the risk group and the non-risk group in pregnant women with singleton pregnancy. The screening efficiency of NIPT was higher in pregnant women in the risk group, which implies that the clinical application of NIPT is inclined to detect high-risk group. CONCLUSIONS: Non-invasive prenatal testing (NIPT) is a rapid and safe screening method with high efficiency. Non-invasive prenatal testing (NIPT) is used for the screening of aneuploidy in twin pregnancy. The efficiency is similar to that of singleton pregnancy, indicating the feasibility of clinical application. However, the efficiency of NIPT screening tends to favor the detection in high-risk groups.


Asunto(s)
Síndrome de Down , Aneuploidia , Síndrome de Down/diagnóstico , Femenino , Humanos , Recién Nacido , Masculino , Embarazo , Diagnóstico Prenatal/métodos , Aberraciones Cromosómicas Sexuales , Trisomía , Síndrome de la Trisomía 13/diagnóstico , Síndrome de la Trisomía 18/diagnóstico
18.
J Phys Chem Lett ; 13(36): 8613-8619, 2022 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-36073976

RESUMEN

Halide double perovskites have aroused substantial research interest because of their unique optical properties and intriguing flexibility for various compositional adjustments. Herein, we report the synthesis and photophysics of rare-earth element yttrium (Y)-based double perovskite single crystals (SCs) and nanocrystals (NCs). The pristine Cs2NaYCl6 bulk SCs exhibit a weak sky-blue emission with a low photoluminescence quantum yield (PLQY) of 7.68% based on the self-trapped exciton (STE), while no PL emission was observed for NCs. Excitingly, the STE emission of SCs and NCs is greatly enhanced via Sb3+ doping. The optimized Cs2NaYCl6:Sb3+ SCs and NCs exhibit high PLQYs up to 82.5% and 51.8%, respectively. Theoretical calculations and charge-carrier dynamic studies demonstrate that the giant emission enhancement after Sb3+ doping is related with the enhancement of the sensitization of the emissive STE states, the passivating of the nonradiative carrier trapping processes, and the regulation of carrier-phonon coupling.

19.
Ann Transl Med ; 10(24): 1364, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36660687

RESUMEN

Background: Anembryonic pregnancy (AP) is the most severe dysmorphogenesis of human embryo development and a frequent presentation of early pregnancy loss (EPL). Studies have analyzed the association between assisted reproductive technologies (ART) and EPL. However, the specific relationship between ART and AP has not been fully elucidated. Several studies suggested that non-genomic anomalies might be related to AP and ART might increase the risk of epigenetic changes, thus possibly detecting some associations between ART and AP. Our study aims to find out any possible risk factors of AP in ART treatments, and translate the results into clinical practice. Methods: A retrospective cohort study was conducted in Nanfang Hospital. Data from 1,765 singleton pregnancies following fresh or frozen-thawed embryo transfer from January 2014 to December 2017 were collated with the inclusion of EPLs and normal live births (NLB). Participants were divided into three groups: NLB (full-term birth with normal body weight infants), EPL (spontaneous pregnancy loss prior to 13 weeks gestation) with embryos (EE), and APs (embryonic pole was invisible in two consecutive ultrasound examinations). The basic characteristics of the patients and the association between ART-related variables and AP were analyzed using one-way analysis of variance (ANOVA) and multivariable logistic regression model, respectively. Products of conception (POC) from AP and EE patients received karyotype analysis using multiplex ligation-dependent probe amplification (MLPA). Results: Blastocyst culture of non-top-quality cleavage stage embryos almost doubled the percentage of AP in EPL (45.9% vs. 24.4%, P=0.037), and the normal euploid rate was significantly higher in the AP group (50.5% vs. 32.3%, P=0.003). Using multivariable logistic regression model, we found that blastocyst transfer and advanced maternal age might be risk factors for AP (OR >1, P<0.05). Deceased ß-HCG level might indicate its occurrence (OR <1, P<0.001) while CoQ10 supplementation might be a protective factor (OR <1, P<0.001). Conclusions: The occurrence of AP may be due to epigenetic abnormalities associated with advanced maternal age and extended in vitro embryo culture, while CoQ10 supplementation may be a potential method in preventing AP. Future multi-center prospective cohort studies should be conducted to verify these results.

20.
Mol Cytogenet ; 15(1): 29, 2022 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-35794576

RESUMEN

OBJECTIVE: Since 2011, noninvasive prenatal testing (NIPT) has undergone rapid expansion, with both utilization and coverage. However, conclusive data regarding the clinical validity and utility of this testing tool are lacking. Thus, there is a continued need to educate clinicians and patients about the current benefits and limitations in order to inform pre- and post-test counseling, pre/perinatal decision making, and medical risk assessment/management. METHODS: This retrospective study included women referred for invasive prenatal diagnosis to confirm positive NIPT results between January 2017 and December 2020. Prenatal diagnosis testing, including karyotyping, chromosomal microarray analysis (CMA) were performed. Positive predictive values (PPVs) were calculated. RESULTS: In total, 468 women were recruited. The PPVs for trisomies 21, 18, and 13 were 86.1%, 57.8%, and 25.0%, respectively. The PPVs for rare chromosomal abnormalities (RCAs) and copy number variants (CNVs) were 17.0% and 40.4%, respectively. The detection of sex chromosomal aneuploidies (SCAs) had a PPV of 20% for monosomy X, 23.5% for 47,XXX, 68.8% for 47,XXY, and 62.5% for 47,XYY. The high-risk groups had a significant increase in the number of true positive cases compared to the low- and moderate-risk groups. CONCLUSIONS: T13, monosomy X, and RCA were associated with lower PPVs. The improvement of cell-free fetal DNA screening technology and continued monitoring of its performance are important.

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