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1.
PLoS Biol ; 20(6): e3001682, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35771762

RESUMO

Around 60% of in vitro fertilized (IVF) human embryos irreversibly arrest before compaction between the 3- to 8-cell stage, posing a significant clinical problem. The mechanisms behind this arrest are unclear. Here, we show that the arrested embryos enter a senescent-like state, marked by cell cycle arrest, the down-regulation of ribosomes and histones and down-regulation of MYC and p53 activity. The arrested embryos can be divided into 3 types. Type I embryos fail to complete the maternal-zygotic transition, and Type II/III embryos have low levels of glycolysis and either high (Type II) or low (Type III) levels of oxidative phosphorylation. Treatment with the SIRT agonist resveratrol or nicotinamide riboside (NR) can partially rescue the arrested phenotype, which is accompanied by changes in metabolic activity. Overall, our data suggests metabolic and epigenetic dysfunctions underlie the arrest of human embryos.


Assuntos
Embrião de Mamíferos , Fertilização in vitro , Embrião de Mamíferos/metabolismo , Epigênese Genética , Histonas/metabolismo , Humanos , Zigoto/metabolismo
2.
Chemistry ; 30(13): e202303394, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38116992

RESUMO

The development of efficient and selective organic synthetic approaches for complex molecules has garnered significant attention due to the need for precise control over molecular structures and functions. Rotaxanes, a type of mechanically interlocked molecules (MIMs), have shown promising applications in various fields including sensing, catalysis, and material science. However, the highly selective synthesis of oligo[n]rotaxanes (mostly n≥3) through controlling host-guest complexation and supramolecular threading assembly process still remains an ongoing challenge. In particular, the utilization of two-dimensional (2D) macrocycles with structural shape-persistency for the synthesis of oligo[n]rotaxanes is rare. In this concept, research on cooperatively threaded host-guest complexation with hydrogen-bonded (H-bonded) aramide macrocycles and selective synthetic protocols of oligo[n]rotaxanes has been summarized. The high efficiency and selectivity in synthesis are ascribed to the synergistic interplay of multiple non-covalent bonding interactions such as hydrogen bonding and intermolecular π-π stacking of macrocycles within the unique supramolecular structure of threaded host-guest complexes. This review focuses on the latest progress in the concepts, synthesis, and properties of H-bonded aramide macrocycle-based oligorotaxanes, and presents an in-depth outlook on challenges in this emerging field.

3.
Pediatr Surg Int ; 40(1): 184, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38995440

RESUMO

PURPOSE: This study evaluated the outcome of pediatric patients with primary vesicoureteral reflux (VUR) and compared of the treatments between continued antibiotic prophylaxis (CAP) and endoscopic injection. METHODS: The clinical data of children diagnosed with primary vesicoureteral reflux from March 2015 to June 2020 who were treated with antibiotics or endoscopic injection were reviewed. Antibiotic was the first-chosen treatment after the diagnosis of VUR in children. Endoscopic treatment consisted of injection of dextran hyaluronic acid copolymer (DX/HA) into the ureteral opening under direct cystoscopy guidance. RESULTS: Fifty-two children (35 males, 17 females) were included in this study, and for a total 90 ureters (14 unilateral, 38 bilateral) were diagnosed with vesicoureteral reflux by Voiding cystourethrography (VCUG). Twenty-two children were treated with antibiotics (8 unilateral, 14 bilateral), for a total of 36 ureters; thirty children were treated by endoscopic injection (6 unilateral, 24 bilateral), for a total of 54 ureters. The injection surgery took 36 ± 17 min including duration of general anesthesia and circumcision and the hospital stay was 2.3 ± 1.3 days. All male patients underwent circumcision simultaneously. There were no drug and allergic reactions in the antibiotic group, and no postoperative complications occurred in the injection group. With 23 months (13-63 months) of mean follow-up, the resolution rate, defined as radiological disappearance of VUR, was 36.1% (13/36) in the antibiotic group and 57.4% (31/54) in the injection group (P = 0.048).Two cases of bilateral reflux in the injection group required a second injection before resolution could be achieved. Thus, the overall success rate of injection was 64.8% (35/54). 9 cases (9/18, 50%) in the antibiotic group had renal scars on DMSA scans, while this was seen in 20 cases (20/23, 86.9%) in the injection group. There was a statistically significant difference between the two groups (P = 0.010).The positive rates of ultrasound between the antibiotic group and the injection group were 45.5% (10/22) and 80.0% (24/30), respectively. There was a statistically significant difference between the two groups in positive rates of ultrasound (P = 0.010). CONCLUSIONS: Endoscopic injection is easy to operate with short surgical time and hospital stay, so it is a safe and feasible treatment. For the treatment of primary vesicoureteral reflux in children, the radiological resolution rate of endoscopic injection is better than antibiotic therapy. In this study, the presence of kidney scars on DMSA and the dilated of the collecting system on ultrasound are the indications for endoscopic injection.


Assuntos
Antibacterianos , Antibioticoprofilaxia , Cistoscopia , Dextranos , Ácido Hialurônico , Refluxo Vesicoureteral , Humanos , Refluxo Vesicoureteral/terapia , Refluxo Vesicoureteral/tratamento farmacológico , Masculino , Feminino , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Ácido Hialurônico/administração & dosagem , Dextranos/administração & dosagem , Pré-Escolar , Estudos Retrospectivos , Cistoscopia/métodos , Antibioticoprofilaxia/métodos , Lactente , Criança , Resultado do Tratamento , Injeções/métodos
4.
Inorg Chem ; 62(23): 9168-9177, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37227426

RESUMO

Selective extraction of palladium from high-level liquid waste (HLLW) is desirable for the sustainable development of nuclear energy and resource recovery. In this work, three tridentate 2,6-bis-triazolyl-pyridine ligands (L-I, L-II, and L-III) bearing different alkyl side chains were synthesized and systematically studied for the complexation and extraction of palladium. Altering the alkyl side chains of the ligands led to pronounced differences in extraction performance. Among the three ligands, L-II decorated with two n-octyl groups exhibited the highest Pd(II) extraction efficiency at acidity levels of 1-5 M HNO3 and outstanding selectivity over 13 coexisting competing metal ions. Results from UV-vis titration experiments and theoretical calculations suggested that the differentiated extraction abilities of the ligands could be because of their different hydrophilicity rather than electron-donating effects. Slope analyses and electrospray ionization-high resolution mass spectrometry (ESI-HRMS) experiments revealed the formation of both L/Pd 1:1 and 2:1 species during the extraction process. These stoichiometries were further confirmed by job plots and NMR titration experiments. The ligands were found to aggregate slightly, especially at higher concentrations, which could result from multiple intermolecular hydrogen bonds as illustrated by X-ray crystallography. The configurations of PdL and PdL2 were further elucidated by analysis of single crystal structure and density-functional theory (DFT) calculations, respectively, where the first coordination sphere of Pd(II) was surrounded by four nitrogen or oxygen atoms in a quadrangular manner. This study provides an alternative method to separate palladium from HLLW and brings a new understanding of the coordination and complexation behaviors of Pd(II) with tridentate nitrogen ligands.

5.
Inorg Chem ; 62(12): 4922-4933, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-36919932

RESUMO

An unmet challenge in the thorium-uranium fuel cycle is the efficient separation of uranium from thorium. Herein, two new tetradentate N,O-hybrid ligands, N,N'-diethyl-N,N'-di-p-tolyl-2,2'-bipyridine-6,6'-dicarboxamide (Et-Tol-BPDA) and N,N'-diethyl-N,N'-di-p-tolyl-2,2'-bipyrimidine-4,4'-dicarboxamide (Et-Tol-BPymDA), comprising a bipyridine or bipyrimidine core and amide moieties were designed and synthesized for selectively complexing and separating U(VI) from Th(IV). The high U(VI)/Th(IV) extraction selectivity was achieved by Et-Tol-BPDA (SFU/Th = 33 at 3 M HNO3) and Et-Tol-BPymDA (SFU/Th = 73 at 3 M HNO3) in nitric acid solutions. The extraction process for U(VI) or Th(IV) with these two ligands primarily proceeded through the solvation mechanism, as evidenced by slope analyses. Thermodynamic studies for the extraction of U(VI) and Th(IV) revealed a spontaneous process. Results from UV-vis spectroscopic titration and slope analyses demonstrated that U(VI) and Th(IV) each form a 1:1 complex with the two ligands both in the monophasic organic solution and the biphasic extraction system. The stability constants of the 1:1 complexes of Et-Tol-BPDA or Et-Tol-BPymDA with U(VI) were found to be larger than those with Th(IV), which coincide well with the high U(VI)/Th(IV) extraction selectivity. The solid-state structures of Et-Tol-BPDA, Et-Tol-BPymDA, and 1:1 complexes of the two ligands with U(VI) or Th(IV) were analyzed by X-ray diffraction technique. The results from this work implicate the potential of bipyridine- and bipyrimidine-derived diamide ligands for uranium/thorium separation.

6.
Mol Ther ; 30(1): 175-183, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-33974999

RESUMO

A couple diagnosed as carriers for lamellar ichthyosis, an autosomal recessive rare disease, encountered two pregnancy losses. Their blood samples showed the same heterozygous c.607C>T mutation in the TGM1 gene. However, we found that about 98.4% of the sperm had mutations, suggesting possible de novo germline mutation. To explore the probability of correcting this mutation, we used two different adenine base editors (ABEs) combined with related truncated single guide RNA (sgRNA) to repair the pathogenic mutation in mutant zygotes. Our results showed that the editing efficiency was 73.8% for ABEmax-NG combined with 20-bp-length sgRNA and 78.7% for Sc-ABEmax combined with 19-bp-length sgRNA. The whole-genome sequencing (WGS) and deep sequencing analysis demonstrated precise DNA editing. This study reveals the possibility of correcting the genetic mutation in embryos with the ABE system.


Assuntos
Adenina , Edição de Genes , Transglutaminases , Edição de Genes/métodos , Heterozigoto , Humanos , Mutação , RNA Guia de Cinetoplastídeos , Transglutaminases/genética
7.
Asia Pac J Clin Nutr ; 32(3): 356-361, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37789656

RESUMO

BACKGROUND AND OBJECTIVES: Lack of professional and accurate diagnosis of malnutrition led to a reduction in Diagnosis Related Group (DRG) payment and a decrease in Case-Mix Index (CMI). The aim of this study was to explore the effects of adding a proper nutritional diagnosis and modifying complication groups on DRG payment and CMI. METHODS AND STUDY DESIGN: Retrospective analysis was performed on patients ad-mitted to the hospital from January to June 2022 who had received a nutritional assessment. Patients were diagnosed as well-nourished, mild malnutrition, moderate malnutrition or severe malnutrition according to patient-generated subjective global assessment (PG-SGA) scores within 24 hours of admission. CMI and DRG hospital internal control standards were recalculated and compared with the original values. RESULTS: A total of 254 patients were enrolled, including 40 patients with mild malnutrition, 74 patients with moderate malnutrition and 122 patients with severe malnutrition. Of all subjects, 111 changed complication groups. The median of the DRG hospital internal control standard (12006.09 vs. 13797.19, p=0.01) and the median of CMI (0.91 vs. 1.04, p=0.026) were significantly higher than those before the diagnostic change. In patients with inflammatory bowel disease (IBD), the CMI value, hospital control standard of DRG, and the classification of DRG were significantly different from those before diagnosis revision (p<0.001). CONCLUSIONS: Fully identification and correct coding of malnutrition cases are conducive for hospitals to receive appropriate DRG compensation, and further contribute to the improvement of medical quality and the economic sustain-ability of hospitals.


Assuntos
Desnutrição , Humanos , Estudos Retrospectivos , Desnutrição/diagnóstico , Desnutrição/epidemiologia , Desnutrição/etiologia , Hospitalização , Grupos Diagnósticos Relacionados , Avaliação Nutricional , Estado Nutricional
8.
J Digit Imaging ; 36(1): 114-123, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36085330

RESUMO

The accuracy of computed tomography angiography (CTA) image interpretation depends on the radiologist. This study aims to develop a new method for automatically detecting intracranial aneurysms from CTA images using deep learning, based on a convolutional neural network (CNN) implemented on the DeepMedic platform. Ninety CTA scans of patients with intracranial aneurysms are collected and divided into two datasets: training (80 subjects) and test (10 subjects) datasets. Subsequently, a deep learning architecture with a three-dimensional (3D) CNN model is implemented on the DeepMedic platform for the automatic segmentation and detection of intracranial aneurysms from the CTA images. The samples in the training dataset are used to train the CNN model, and those in the test dataset are used to assess the performance of the established system. Sensitivity, positive predictive value (PPV), and false positives are evaluated. The overall sensitivity and PPV of this system for detecting intracranial aneurysms from CTA images are 92.3% and 100%, respectively, and the segmentation sensitivity is 92.3%. The performance of the system in the detection of intracranial aneurysms is closely related to their size. The detection sensitivity for small intracranial aneurysms (≤ 3 mm) is 66.7%, whereas the sensitivity of detection for large (> 10 mm) and medium-sized (3-10 mm) intracranial aneurysms is 100%. The deep learning architecture with a 3D CNN model on the DeepMedic platform can reliably segment and detect intracranial aneurysms from CTA images with high sensitivity.


Assuntos
Aprendizado Profundo , Aneurisma Intracraniano , Humanos , Angiografia por Tomografia Computadorizada , Tomografia Computadorizada por Raios X/métodos , Angiografia Digital/métodos , Angiografia Cerebral/métodos , Sensibilidade e Especificidade
9.
Int J Mol Sci ; 24(4)2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36835189

RESUMO

Cytoskeleton protein 4.1 is an essential class of skeletal membrane protein, initially found in red blood cells, and can be classified into four types: 4.1R (red blood cell type), 4.1N (neuronal type), 4.1G (general type), and 4.1B (brain type). As research progressed, it was discovered that cytoskeleton protein 4.1 plays a vital role in cancer as a tumor suppressor. Many studies have also demonstrated that cytoskeleton protein 4.1 acts as a diagnostic and prognostic biomarker for tumors. Moreover, with the rise of immunotherapy, the tumor microenvironment as a treatment target in cancer has attracted great interest. Increasing evidence has shown the immunoregulatory potential of cytoskeleton protein 4.1 in the tumor microenvironment and treatment. In this review, we discuss the role of cytoskeleton protein 4.1 within the tumor microenvironment in immunoregulation and cancer development, with the intention of providing a new approach and new ideas for future cancer diagnosis and treatment.


Assuntos
Proteínas do Citoesqueleto , Neoplasias , Humanos , Proteínas do Citoesqueleto/metabolismo , Citoesqueleto/metabolismo , Proteínas de Membrana/metabolismo , Neoplasias/metabolismo , Imunoterapia , Microambiente Tumoral
10.
Molecules ; 28(11)2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37298912

RESUMO

Research on stimuli-responsive host-guest systems is at the cutting edge of supramolecular chemistry, owing to their numerous potential applications such as catalysis, molecular machines, and drug delivery. Herein, we present a multi-responsive host-guest system comprising azo-macrocycle 1 and 4,4'-bipyridinium salt G1 for pH-, photo-, and cation- responsiveness. Previously, we reported a novel hydrogen-bonded azo-macrocycle 1. The size of this host can be controlled through light-induced E↔Z photo-isomerization of the constituent azo-benzenes. The host is found in this work to be capable of forming stable complexes with bipyridinium/pyridinium salts, and implementing guest capture and release with G1 under light in a controlled manner. The binding and release of the guest in the complexes can also be easily controlled reversibly by using acid and base. Moreover, the cation competition-induced dissociation of the complex 1a2⊃G1 is achieved. These findings are expected to be useful in regulating encapsulation for sophisticated supramolecular systems.


Assuntos
Sistemas de Liberação de Medicamentos , Compostos de Piridínio , Compostos de Piridínio/química
11.
Angew Chem Int Ed Engl ; 62(14): e202216690, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-36652350

RESUMO

Use of abiotic chemical systems for understanding higher order superstructures is challenging. Here we report a ring-in-ring(s) system comprising a hydrogen-bonded macrocycle and cyclobis(paraquat-o-phenylene) tetracation (o-Box) or cyclobis(paraquat-p-phenylene) tetracation (CBPQT4+ , p-Box) that assembles to construct discrete higher order structures with adaptive conformation. As indicated by mass spectrometry, computational modeling, NMR spectroscopy, and single-crystal X-ray diffraction analysis, this ring-in-ring(s) system features the box-directed aggregation of multiple macrocycles, leading to generation of several stable species such as H4G (1 a/o-Box) and H5G (1 a/o-Box). Remarkably, a dimeric shish-kebab-like ring-in-rings superstructure H7G2 (1 a/o-Box) or H8G2 (1 a/p-Box) is formed from the coaxial stacking of two ring-in-rings units. The formation of such unique dimeric superstructures is attributed to the large π-surface of this 2D planar macrocycle and the conformational variation of both host and guest.

12.
Inorg Chem ; 61(28): 10694-10704, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35785788

RESUMO

Controlling the orderly assembly of molecular building blocks for the formation of the desired architectural, chemical, and physical properties of the resulting solid-state materials remains a long-term goal and deserves to be examined. In this work, we propose a patterning strategy for modular assembly and structural regulation of mixed-ligand uranyl coordination polymers (CPs) through the combination of couples of organic ligands with complementary molecular geometry and well-matched coordination modes. By using a 5-(p-tolyldiazenyl)isophthalic acid ligand (H2ptdi) with different rigid linear bicarboxylic acid linkers to construct a well-defined ladder-like pattern, five novel isostructural uranyl coordination polymers, [(UO)2(ptdi)(bdc)0.5](dma) (1), [(UO)2(ptdi)(bpdc)0.5](dma) (2), [(UO)2(ptdi)(tpdc)0.5](dma) (3), [(UO)2(ptdi)(ndc)0.5](dma) (4), and [(UO)2(ptdi) (pdc)0.5](dma) (5) {H2bdc, 1,4-dicarboxybenzene; H2bpdc, 4,4'-biphenyldicarboxylic acid; H2tpdc, terphenyl-4,4″-dicarboxylic acid; H2ndc, 2,6-naphthalenedicarboxylic acid; H2pdc, 1,6-pyrenedicarboxylic acid; [dma]+, [(CH3)2NH2]+}, were successfully synthesized. Structural analysis reveals that 1-5 have similar ladder-like units but different sizes of one-dimensional nanochannels and interlayer spacing due to the different lengths and widths of the linkers. Because of the changes in interlayer spacing of these isostructural cationic frameworks, differences in the performance of Eu3+ ion exchange with [dma]+ are observed. Moreover, those compounds with high phase purity have been further characterized by thermogravimetric analysis, infrared spectroscopy, and luminescence spectroscopy, element analysis, PXRD and UV spectroscopy. Among them, compound 3 with strong fluorescence can selectively detect Fe3+ over several competing metal cations in aqueous solution. This work not only provides a feasible patterning method for effectively regulating the modular synthesis of functional coordination polymers but also enriches the library of uranyl-based coordination polymers with intriguing structures and functionality.

13.
Org Biomol Chem ; 20(46): 9023-9051, 2022 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-36128982

RESUMO

As a classic example of nearly planar cyclic compounds, hydrogen-bonded aromatic amide (H-bonded aramide) macrocycles, consisting of consecutive intramolecular hydrogen bonds and aromatic residues, receive considerable research attention due to their rich host-guest chemistry. This review provides a detailed summary of the synthesis, properties and functions of H-bonded aramide macrocycles and their derivatives. Herein, the constitutional patterns of these macrocycles are divided into two subcategories: interior hydrogen bonding motifs and exterior hydrogen bonding motifs. Based on these two motifs, we summarize the facile synthesis, self-assembly, host-guest interaction complexation of H-bonded aramide macrocycles and the resulting applications such as molecular recognition, artificial ion channels, soft materials, supramolecular catalysis, and artificial molecular machines. The development of H-bonded aramide macrocycles is still in its infancy, although a considerable number of examples have been reported. We hope that this review will provide useful information and unlock new opportunities in this field.


Assuntos
Amidas , Compostos Macrocíclicos , Amidas/química , Estrutura Molecular , Compostos Macrocíclicos/química , Hidrogênio , Ligação de Hidrogênio
14.
BMC Pediatr ; 22(1): 224, 2022 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-35468769

RESUMO

BACKGROUND: Parenteral Nutrition (PN) is preferred when patient is unable to eat. Most clinically widely used lipid emulsion is now attracting more attention in its stability and adverse reactions. We report here the first case of lipid emulsions caused hypertension. CASE PRESENTATION: A 1.5 years old girl was diagnosed with neuroblastoma and underwent chemotherapy subsequently followed by resection surgery. She received PN for nutritional support after surgery. with the initiation of PN, this patient developed hypertension. Possible causes of hypertension were evaluated. After the discontinuation of lipid emulsions in PN, her hypertensive symptoms ceased. The lipid emulsion was therefore considered as the cause of her hypertension. CONCLUSIONS: The pathogenesis of hypertension caused by fatty milk is possibly associated with increased production of reactive oxygen species, increased oxidative stress and vasoconstriction.


Assuntos
Hipertensão , Neuroblastoma , Criança , Emulsões Gordurosas Intravenosas/efeitos adversos , Feminino , Humanos , Hipertensão/induzido quimicamente , Lactente , Lipídeos , Neuroblastoma/cirurgia , Nutrição Parenteral/efeitos adversos
15.
Urol Int ; 106(12): 1226-1232, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36244331

RESUMO

INTRODUCTION: The aim of this study was to compare the efficacy of mirabegron plus tamsulosin to tamsulosin monotherapy in terms of ureteral stent-related discomfort after ureteroscopic lithotripsy. METHODS: A total of 102 patients undergoing ureteroscopic lithotripsy and silicone ureteral stent placement were enrolled in this study. Patients were randomized 1:1 to receive either tamsulosin 0.4 mg once daily or mirabegron 50 mg + tamsulosin 0.4 mg once daily during the stenting period. Before the operation, the IPSS, QOL, and pain score were collected. On the day of ureteral stent removal, the USSQ, analgesic usage amount was collected and recorded. RESULTS: The median USSQ-body pain score in the tamsulosin group and tamsulosin + mirabegron group was 15 and 16, respectively (p = 0.530). The median analgesic usage in the two groups was 3 and 2, respectively (p = 0.170). The median USSQ-urinary symptoms, USSQ-general health, USSQ-work performance, USSQ-sexual matters, and USSQ-additional problems in the two groups were 26 and 26 (p = 0.194), 11 and 12 (p = 0.068), 12 and 13 (p = 0.105), 2 and 2 (p = 0.437), 9 and 9 (p = 0.533), respectively. The international patients used more analgesics than Chinese patients (6 vs. 1, p = 0.015). CONCLUSION: Compared to tamsulosin alone, tamsulosin + mirabegron showed no additional benefit on the ureteral stent-related pain control after ureteroscopic lithotripsy and silicone stent placement. There was no significant difference on the analgesic usage and USSQ scores between the two groups. Chinese patients request fewer analgesics than international patients.


Assuntos
Qualidade de Vida , Stents , Humanos , Tansulosina/uso terapêutico , Estudos Prospectivos , Dor
16.
Sensors (Basel) ; 22(19)2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36236434

RESUMO

In infrared small target detection, the infrared patch image (IPI)-model-based methods produce better results than other popular approaches (such as max-mean, top-hat, and human visual system) but in some extreme cases it suffers from long processing times and inconsistent performance. In order to overcome these issues, we propose a novel approach of dividing the traditional target detection process into two steps: suppression of background noise and elimination of clutter. The workflow consists of four steps: after importing the images, the second step applies the alternating direction multiplier method to preliminarily remove the background. Comparatively to the IPI model, this step does not require sliding patches, resulting in a significant reduction in processing time. To eliminate residual noise and clutter, the interim results from morphological filtering are then processed in step 3 through an improved new top-hat transformation, using a threefold structuring element. The final step is thresholding segmentation, which uses an adaptive threshold algorithm. Compared with IPI and the new top-hat methods, as well as some other widely used methods, our approach was able to detect infrared targets more efficiently (90% less computational time) and consistently (no sudden performance drop).


Assuntos
Algoritmos , Humanos
17.
J Cell Mol Med ; 2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34037315

RESUMO

Oocyte ageing is a key bottleneck and intractable challenge for in vitro fertilization treatment of aged female patients. The underlying molecular mechanisms of human oocyte ageing remain to be elucidated. Hence, this study aims to investigate the key genes and relevant biological signalling pathways involved in human oocyte ageing. We isolated mRNA for single-cell RNA sequencing from MII human oocytes donated by patients undergoing intracytoplasmic sperm injection. Nine RNA-seq datasets were analyzed, which included 6 older patients(average 42.67±2.25 years) and 3 younger patients (average 25.67±2.08 years). 481 differentially expressed genes (DEGs) were identified, including 322 upregulated genes enriched in transcription, ubiquitination, epigenetic regulation, and cellular processes, and 159 downregulated genes enriched in ubiquitination, cell cycle, signalling pathway, and DNA repair. The STRING database was used to analyse protein-protein interactions, and the Cytoscape software was used to identify hub genes. From these DEGs, 17 hub genes were identified including 12 upregulated genes (UBE2C, UBC, CDC34, UBR1, KIF11, ASF1B, PRC1, ESPL1, GTSE1, EXO1, UBA1, KIF4A) and 5 downregulated genes (UBA52, UBE2V2, SKP1, CCNB1, MAD2L1). The significant key biological processes that are associated with these hub genes include ubiquitin-mediated proteolysis, ubiquitination-related pathways, oocyte meiosis, and cell cycle. Among these, UBE2C may play a crucial role in human oocyte ageing.

18.
Inorg Chem ; 60(12): 8519-8529, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34096273

RESUMO

Monitoring and quantification of the photoresponsive behavior of metal-organic frameworks that respond to a light stimulus are crucial to establish a clear structure-activity relationship related to light regulation. Herein, we report the first azobenzene-modified photoresponsive thorium-organic framework (Th-Azo-MOF) with the formula [Th6O4(OH)4(H2O)6L6] (H2L = (E)-2'-p-tolyldiazenyl-1,1':4',4'-terphenyl-4,4″-dicarboxylic acid), in which the utilization of a thorium cluster as a metal node leads to one of the largest pore sizes among all the azobenzene-containing metal-organic frameworks (MOFs). The phototriggered transformation of the trans isomer to the cis isomer is monitored and characterized quantitatively by comprehensive analyses of NMR and UV spectroscopy, which reveals that the maximum isomerization ratio of cisTh-Azo-MOF in the solid state is 19.7% after irradiation for 120 min, and this isomerization is reversible and can be repeated several times without apparent performance changes. Moreover, the isomerization-related difference in the adsorption of the Rhodamine B guest is also illustrated and a possible photoregulated mechanism is proposed. This work will shed light on new explorations for constructing functionalized actinide porous materials by the elegant combination of actinide nodes with tailored organic ligands and furthermore will provide a comprehensive understanding of photoisomerization processes in MOF solids and insight into the mechanism on photoregulated cargo adsorption and release by photoactive MOFs.

19.
Molecules ; 26(13)2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34279403

RESUMO

A hydrogen-bonded (H-bonded) amide macrocycle was found to serve as an effective component in the host-guest assembly for a supramolecular chirality transfer process. Circular dichroism (CD) spectroscopy studies showed that the near-planar macrocycle could produce a CD response when combined with three of the twelve L-α-amino acid esters (all cryptochiral molecules) tested as possible guests. The host-guest complexation between the macrocycle and cationic guests was explored using NMR, revealing the presence of a strong affinity involving the multi-point recognition of guests. This was further corroborated by density functional theory (DFT) calculations. The present work proposes a new strategy for amplifying the CD signals of cryptochiral molecules by means of H-bonded macrocycle-based host-guest association, and is expected to be useful in designing supramolecular chiroptical sensing materials.


Assuntos
Dicroísmo Circular/métodos , Compostos Macrocíclicos/química , Aminoácidos/química , Ésteres/química
20.
J Phys Chem A ; 124(18): 3626-3635, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32282201

RESUMO

Due to the role of dyes in dye-sensitized solar cells (DSSCs), designing novel dye sensitizers is an effective strategy to improve the power conversion efficiency. To this end, the fundamental issue is understanding the sensitizer's trilateral relationship among its molecular structure, optoelectronic properties, and photovoltaic performance. Considering the good performance of N-annulated perlyene dye sensitizers, the geometries, electronic structures, and excitations of the selected representative organic dye sensitizers C276, C277, and C278 as well as dyes adsorbed on TiO2 clusters were calculated in order to investigate the relationship between molecular structures and properties. It was found that fusing thienyl to N-annulated perlyene can elevate the highest occupied molecular orbital (HOMO) energy, reduce the orbital energy gap, increase the density of states, expand the HOMO to the benzothiadiazole moiety, enhance the charge transfer excitation, elongate the fluorescence lifetime, amplify the light harvesting efficiency, and induce a red-shift of the absorption spectra. The transition configurations and molecular orbitals of the dye-adsorbed systems support that the electron injection in DSSCs based on these dyes is a fast mode. Based on extensive analysis of the electronic structures and excitation properties of these dye sensitizers and the dye-adsorbed systems, we present new quantities as open-circuit voltage and short-circuit current density descriptors that celebrate the quantitative bridge between the photovoltaic parameters and the electronic structure-related properties in order to expose the relationship between properties and performance. The results of this work are critical for the design of novel dye sensitizers for solar cells.

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