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1.
Nano Lett ; 23(9): 3762-3768, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37096965

RESUMO

Lead-free metal halide nanocrystals (NCs) have aroused increasing attention due to their unique optoelectronic properties based on localized excitons (LEs). However, the vital influencing factors for the LEs based photoluminescence (PL) are still not well-understood due to the coupling of various intrinsic and extrinsic factors of the NCs. Herein, by engineering the phase, size, morphology, and chemical composition, we are able to decouple the intrinsic and extrinsic factors of manganese doped cesium zinc-halide NCs. We found both the intrinsic metal-halide coordination field and the extrinsic crystal defects have significant influences on the LEs' recombination and energy transfer processes, and hence determine the PL efficiency. Unlike for the free excitons (FEs) based PL, the phase as well as the crystal morphology do not play major roles for the LEs based PL. This work provides a new insight for the study of LE dynamics of metal halide NCs.

2.
Adv Mater ; 36(2): e2302140, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37801733

RESUMO

Metal halide nanocrystals (NCs) with high photoluminescence quantum yield (PLQY) are desirable for lighting, display, and X-ray detection. Herein, the novel lanthanide-based halide NCs are committed to designing and optimizing the optical and scintillating properties, so as to unravel the PL origin, exciton dynamics, and optoelectronic applications. Sb-doped zero-dimensional (0D) Cs3 TbCl6 NCs exhibit a green emission with a narrow full width of half maximum of 8.6 nm, and the best PLQY of 48.1% is about three times higher than that of undoped NCs. Experiments and theoretical calculations indicate that 0D crystalline and electronic structures make the exciton highly localized on [TbCl6 ]3- octahedron, which boosts the Cl- -Tb3+ charge transfer process, thus resulting in bright Tb3+ emission. More importantly, the introduction of Sb3+ not only facilitates the photon absorption transition, but also builds an effective thermally boosting energy transfer channel assisted by [SbCl6 ]3- -induced self-trapped state, which is responsible for the PL enhancement. The high luminescence efficiency and negligible self-absorption of the Cs3 TbCl6 : Sb nanoscintillator enable a more sensitive X-ray detection response compared with undoped sample. The study opens a new perspective to deeply understand the excited state dynamics of metal halide NCs, which helps to design high-performance luminescent lanthanide-based nanomaterials.

3.
Clin Nucl Med ; 48(1): 56-57, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36241029

RESUMO

ABSTRACT: Umbilical endometriosis is a rare event. A 44-year-old woman complained of a palpable abdominal mass with bloody secretion and chronic abdominal pain for 2 months. 18 F-FDG PET/CT images demonstrated multiple foci of increased tracer uptake indicating malignant tumor with metastases in the region of umbilicus and lower segment of the esophagus. Unexpectedly, the subsequent histology and immunohistochemistry of the umbilical lesion demonstrated endometriosis.


Assuntos
Endometriose , Neoplasias , Adulto , Feminino , Humanos , Endometriose/diagnóstico por imagem , Endometriose/patologia , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Umbigo/diagnóstico por imagem , Diagnóstico Diferencial
4.
Ultrason Sonochem ; 93: 106301, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36669430

RESUMO

In this paper, the cavitation bubble dynamics near two spherical particles of the same size are investigated theoretically and experimentally. According to the Weiss theorem, the flow characteristics and the Kelvin impulse are obtained and supported by the sufficient experimental data. In terms of the initial bubble position, the bubble size and the distance between the two particles, the collapse morphology and the movement characteristics of the bubble are revealed in detail. The main findings include: (1) Based on a large number of experimental results, it is found that the Kelvin impulse theoretical model established in this paper can effectively predict the movement characteristics of the cavitation bubble near two particles of the same size. (2) When the initial bubble position is gradually away from the particles along the horizontal symmetry axis near two particles of the same size, the movement distance of the bubble centroid in the first period increases first and then decreases. (3) When the initial position of the bubble centroid is at the asymmetric position near the two particles, the movement direction of the bubble centroid is biased towards the particle closer to the bubble, but not towards the center of this particle.

5.
J Phys Chem Lett ; 14(38): 8577-8583, 2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37725534

RESUMO

Inorganic halide double perovskite (DP) nanocrystals (NCs) have attracted great attention because of their nontoxicity, mild reaction conditions, good stability, and excellent optical and optoelectronic properties. Herein, we prepare the inorganic terbium halide DP Cs2BTbCl6 (B = Na or Ag) NCs with bright green photoluminescence (PL) emission. The Na-Tb-based DP NCs exhibit better PL properties compared with the Ag-Tb-based DP NCs, which is due to Cs2NaTbCl6 NCs having a more localized charge carrier distribution on the [TbCl6]3- octahedron. The incorporation of Sb3+ dopant in Cs2NaTbCl6 NCs can construct a more efficient energy transfer process, resulting in a doubling of PL efficiency. Furthermore, Cs2NaTbCl6: Sb3+ NCs possess excellent X-ray scintillating performance with a low-dose detection limit of 140 nGyair/s, which is nearly 5 times more sensitive than the undoped NCs. The optimized NCs show great application prospects in X-ray imaging. This work helps deepen the understanding of the luminescence mechanism, excited state dynamics, and scintillation property in Tb-based DP NCs.

6.
Artigo em Inglês | MEDLINE | ID: mdl-35399633

RESUMO

Objectives: In this systematic review, the effects of acupuncture combined with moxibustion on reproductive and metabolic outcomes in patients with polycystic ovary syndrome (PCOS) were evaluated. Methods: Randomized controlled trials (RCTs) assessing acupuncture combined with moxibustion + basic treatment (experimental group) versus basic treatment alone (control group) for treating PCOS were identified from English and Chinese databases up to November 3, 2021. Outcomes related to pregnancy, ovulation, miscarriage, sex hormones, and metabolic disorders were of interest. In the meta-analysis, risk ratios (RRs) and mean differences (MDs) and their 95% confidence intervals (CIs) were used as effect measures. Results: Twenty-five RCTs (n = 1991) were included. The pooled results showed that the experimental group had significant increases in the pregnancy rate (RR 1.81, 95% CI 1.58 to 2.08) and ovulation rate (RR 1.31, 95% CI 1.22 to 1.40) and decreases in the miscarriage rate (RR 0.45, 95% CI 0.28 to 0.73), and ovarian volume (MD -0.75 cm3, 95% CI -1.30 to -0.20). In the experimental group, improvements in the luteinizing hormone (LH) level, the LH-to-follicle-stimulating hormone (FSH) ratio, total testosterone level, fasting insulin level, and body mass index, but not in FSH, oestradiol, or dehydroepiandrosterone sulfate levels, were significantly greater. All reported adverse events were mild. Based on the limitations of risk of bias, inconsistency, imprecision, and/or publication bias, the level of evidence was judged to be moderate for the pregnancy rate, ovulation rate, miscarriage rate, LH level, and LH/FSH ratio and very low for the other outcomes. Conclusion: Among patients with PCOS, using acupuncture combined with moxibustion as a complementary therapy to basic treatments can improve pregnancy, ovulation, and miscarriage rates, the levels some sex hormones, and metabolic indicators, with good safety. Additionally, this combination therapy may have no effect on the FSH, oestradiol, or dehydroepiandrosterone sulfate level.

7.
Medicine (Baltimore) ; 100(29): e26699, 2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34398042

RESUMO

BACKGROUND: Endometriosis (EMs) affects about 10% of women of childbearing age. It is defined as functional endometrial tissue appearing in other parts of the uterine cavity, manifested by varying degrees of pelvic pain and pelvic mass, etc. Therefore, to improve the therapeutic effect of endometriosis, we must constantly explore new ways to treat the disease. The purpose of this study is to evaluate the effectiveness and safety of the combined use of laparoscopy and traditional Chinese medicine in the treatment of patients with EMs. METHODS: A systematic literature search will be conducted at China National Knowledge Infrastructure, WanFang databases, VIP, SinoMed, PubMed, Embase, Web of Science, and the Cochrane library. The search period limit is from the time the date of database establishment to June 21, 2021. To ensure the comprehensiveness of the search, relevant references and conference literature are also included. The risk of bias in the final included studies will be evaluated based on the guidelines of the Cochrane Handbook for Systematic Reviews of Interventions. The RevMan software will be employed to perform data synthesis and statistical analysis. RESULTS: The effectiveness and safety of laparoscopic surgery combined with traditional Chinese medicine decoction in the treatment of patients with EMs will be systematically evaluated. CONCLUSION: The results of this study will provide strong evidence for judging whether laparoscopy combined with traditional Chinese medicine decoction is an effective strategy for the treatment of patients with EMs.


Assuntos
Medicamentos de Ervas Chinesas , Endometriose , Feminino , Humanos , Terapia Combinada , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/uso terapêutico , Endometriose/tratamento farmacológico , Endometriose/cirurgia , Laparoscopia , Fitoterapia , Projetos de Pesquisa , Metanálise como Assunto , Revisões Sistemáticas como Assunto
8.
Eur J Radiol ; 124: 108840, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31981879

RESUMO

PURPOSE: To establish an accurate and reliable equation for kidney depth estimation in adult patients from different Chinese geographical regions. METHOD: This multicenter study enrolled Eastern Asian Chinese patients with abdominal PET/CT scans at 26 imaging centers from six macro-regions across China in 3 years. Age, gender, height, weight, primary disease and its extent on PET scans of the participants were collected as potential predictive factors. Kidney depth on CT, defined as the average of the vertical distances from the posterior skin to the farthest anterior and closest posterior surfaces of each kidney, was measured as the standard reference. The new kidney depth model was constructed using a multiple regression model, and its performance was compared to those of three established models by computing the absolute value of estimation errors in comparison with CT-measured kidney depth. RESULTS: A total of 2502 patients were enrolled and classified into training (n=1653) and testing (n = 849) subsets. In the training subset, two kidney depth models were constructed: Left (cm): 0.013×age+0.117×gender-0.044×height+0.087×weight+7.951, Right (cm): 0.005×age+0.013×gender-0.035×height+0.082×weight+7.266 (weight: kg, height: cm, gender = 0 if female, 1 if male). In the testing subset, one-way analysis of variance showed that the estimation errors of the new models did not significantly differ among the 6 regions. Bland-Altman analysis determined that new equations had lower estimated biases (left: 0.039 cm, right: 0.018 cm) compared with other existing models. CONCLUSION: The new equations were highly accurate for kidney depth estimation in adults from all over China, with lower estimation errors compared to other established models.


Assuntos
Rim/anatomia & histologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Tomografia Computadorizada por Raios X/métodos , Adulto Jovem
9.
Nucl Med Commun ; 36(5): 452-60, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25591074

RESUMO

OBJECTIVE: The aim of this study was to explore the targeting ability and metabolic characteristics of the technetium-99m-labeled single-domain antibody (99mTc-sdAb) EG2 targeting epidermal growth factor receptor (EGFR) through an in-vitro and in-vivo study. MATERIALS AND METHODS: The sdAb EG2 was radiolabeled with Tc using a tricarbonyl kit. The EGFR expression level of A431 and OCM-1 cells was confirmed using immunofluorescence staining. Cell binding, blocking, uptake, and efflux studies were performed to investigate the binding specificity of 99mTc-sdAb EG2 in vitro. Single-photon emission computed tomography imaging and biodistribution studies were used to explore the targeting abilities and metabolic characteristics of Tc-sdAb EG2 in vivo. RESULTS: 99mTc-sdAb EG2 was successfully prepared with labeling yields of 60-71% and specific activity of 1.83±0.29 GBq/mg (n=3). Immunofluorescence staining revealed high and low EGFR expression on the surface of A431 and OCM-1 cells, respectively. The binding affinity of 99mTc-sdAb EG2 to A431 cells was 43.53±1.89 nmol/l. 99mTc-sdAb EG2 uptake in A431 cells in vitro could be blocked by ∼19, 40, and 66% in the presence of excess unlabeled sdAb EG2 at 100, 500, and 1000 nmol/l, respectively. Single-photon emission computed imaging indicated that A431 tumor images could be clearly displayed at early scan time points after 99mTc-sdAb EG2 injection, even as early as 1 h. Biodistribution study showed that the A431 tumor uptake of 99mTc-sdAb EG2 was blocked by about 51% at 3 h after coinjecting excess of sdAb EG2. However, there were almost no OCM-1 tumor images at the corresponding scan time points and the OCM-1 tumor uptake was only 0.40±0.13% injected dose per gram of tissue (n=5) at 3 h. CONCLUSION: This study demonstrated that sdAb EG2 can effectively target EGFR in vitro and in vivo in tumors, suggesting that it could be used as a molecular probe for EGFR detection.


Assuntos
Receptores ErbB/imunologia , Anticorpos de Domínio Único/imunologia , Tecnécio , Animais , Transporte Biológico , Linhagem Celular Tumoral , Humanos , Marcação por Isótopo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Radioquímica , Anticorpos de Domínio Único/química , Anticorpos de Domínio Único/metabolismo , Distribuição Tecidual , Tomografia Computadorizada de Emissão de Fóton Único
10.
PLoS One ; 9(3): e90543, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24608323

RESUMO

PURPOSE: Non-invasive techniques to monitor the survival and migration of transplanted stem cells in real-time is crucial for the success of stem cell therapy. The aim of this study was to explore multimodality molecular imaging to monitor transplanted stem cells with a triple-fused reporter gene [TGF; herpes simplex virus type 1 thymidine kinase (HSV1-tk), enhanced green fluorescence protein (eGFP), and firefly luciferase (FLuc)] in acute myocardial infarction rat models. METHODS: Rat myocardial infarction was established by ligating the left anterior descending coronary artery. A recombinant adenovirus carrying TGF (Ad5-TGF) was constructed. After transfection with Ad5-TGF, 5 × 10(6) bone marrow mesenchymal stem cells (BMSCs) were transplanted into the anterior wall of the left ventricle (n = 14). Untransfected BMSCs were as controls (n = 8). MicroPET/CT, fluorescence and bioluminescence imaging were performed. Continuous images were obtained at day 2, 3 and 7 after transplantation with all three imaging modalities and additional images were performed with bioluminescence imaging until day 15 after transplantation. RESULTS: High signals in the heart area were observed using microPET/CT, fluorescence and bioluminescence imaging of infarcted rats injected with Ad5-TGF-transfected BMSCs, whereas no signals were observed in controls. Semi-quantitative analysis showed the gradual decrease of signals in all three imaging modalities with time. Immunohistochemistry assays confirmed the location of the TGF protein expression was the same as the site of stem cell-specific marker expression, suggesting that TGF tracked the stem cells in situ. CONCLUSIONS: We demonstrated that TGF could be used as a reporter gene to monitor stem cells in a myocardial infarction model by multimodality molecular imaging.


Assuntos
Imagem Molecular/métodos , Imagem Multimodal/métodos , Isquemia Miocárdica/terapia , Transplante de Células-Tronco/métodos , Animais , Imuno-Histoquímica , Reação em Cadeia da Polimerase , Ratos , Ratos Sprague-Dawley
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