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1.
Angew Chem Int Ed Engl ; : e202401433, 2024 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-38433099

RESUMO

We introduce the heterocumulene ligand [(Ad)NCC(tBu)]- (Ad=1-adamantyl (C10H15), tBu=tert-butyl, (C4H9)), which can adopt two forms, the azaalleneyl and ynamide. This ligand platform can undergo a reversible chelotropic shift using Brønsted acid-base chemistry, which promotes an unprecedented spin-state change of the [VIII] ion. These unique scaffolds are prepared via addition of 1-adamantyl isonitrile (C≡NAd) across the alkylidyne in complexes [(BDI)V≡CtBu(OTf)] (A) (BDI-=ArNC(CH3)CHC(CH3)NAr), Ar=2,6-iPr2C6H3) and [(dBDI)V≡CtBu(OEt2)] (B) (dBDI2-=ArNC(CH3)CHC(CH2)NAr). Complex A reacts with C≡NAd, to generate the high-spin [VIII] complex with a κ1-N-ynamide ligand, [(BDI)V{κ1-N-(Ad)NCC(tBu)}(OTf)] (1). Conversely, B reacts with C≡NAd to generate a low-spin [VIII] diamagnetic complex having a chelated κ2-C,N-azaalleneyl ligand, [(dBDI)V{κ2-N,C-(Ad)NCC(tBu)}] (2). Theoretical studies have been applied to better understand the mechanism of formation of 2 and the electronic reconfiguration upon structural rearrangement by the alteration of ligand denticity between 1 and 2.

2.
Theriogenology ; 218: 193-199, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38330863

RESUMO

The purpose of this study was to compare the efficiency of the production of cloned transgenic Yucatan miniature pigs (YMPs) using two recipient breeds, i.e., YMPs and domestic pigs (DPs), under various embryo transfer conditions. We initially assessed the in vitro developmental competence of embryos obtained via somatic cell nuclear transfer (SCNT) from three different transgenic donor cells. No difference was observed among the three groups regarding developmental competence. Furthermore, the cloning efficiency remained consistent among the three groups after the transfer of the SCNT embryos to each surrogate mother. Subsequently, to compare the efficiency of the production of cloned transgenic YMPs between the two recipient breeds using varying parameters, including ovulation status (preovulation and postovulation), duration of in vitro culture (IVC) (incubated within 24 h and 24-48 h), and the number of transferred SCNT embryos (less than and more than 300), we assessed the pregnancy rates, delivery rates, mean offspring counts, and cloning efficiency. Regarding the ovulation status, YMPs exhibited higher pregnancy rates, delivery rates, and cloning efficiency compared with DPs in both statuses. Moreover, the pregnancy rates, delivery rates, and cloning efficiency were affected by the ovulation status in DPs, but not in YMPs. The comparison of IVC duration between groups revealed that YMPs had higher pregnancy rates vs. DPs in both conditions. SCNT embryos cultured for 24-48 h in YMPs yielded higher delivery rates and cloning efficiency compared with those cultured for less than 24 h in DPs. Finally, the analysis based on the number of transferred SCNT embryos showed that both the pregnancy and delivery rates were higher in YMPs vs. DPs. However, the highest average number of offspring was obtained when more than 300 SCNT embryos were transferred into DPs, whereas the cloning efficiency was higher in YMPs vs. DPs. Our results suggest that YMPs are more suitable recipients than are DPs under various conditions for the production of cloned transgenic YMPs.


Assuntos
Clonagem de Organismos , Técnicas de Transferência Nuclear , Gravidez , Feminino , Suínos/genética , Animais , Porco Miniatura/genética , Animais Geneticamente Modificados , Clonagem de Organismos/veterinária , Clonagem de Organismos/métodos , Técnicas de Transferência Nuclear/veterinária , Transferência Embrionária/veterinária , Transferência Embrionária/métodos
3.
J Chem Inf Model ; 64(3): 677-689, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38270063

RESUMO

Thermally activated delayed fluorescence (TADF) material has attracted great attention as a promising metal-free organic light-emitting diode material with a high theoretical efficiency. To accelerate the discovery of novel TADF materials, computer-aided material design strategies have been developed. However, they have clear limitations due to the accessibility of only a few computationally tractable properties. Here, we propose TADF-likeness, a quantitative score to evaluate the TADF potential of molecules based on a data-driven concept of chemical similarity to existing TADF molecules. We used a deep autoencoder to characterize the common features of existing TADF molecules with common chemical descriptors. The score was highly correlated with the four essential electronic properties of TADF molecules and had a high success rate in large-scale virtual screening of millions of molecules to identify promising candidates at almost no cost, validating its feasibility for accelerating TADF discovery. The concept of TADF-likeness can be extended to other fields of materials discovery.


Assuntos
Aprendizado Profundo , Desenho Assistido por Computador , Eletrônica , Fluorescência
4.
J Magn Reson Imaging ; 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37477575

RESUMO

BACKGROUND: While breast ultrasound (US) is a useful tool for diagnosing breast masses, it can entail false-positive biopsy results because of some overlapping features between benign and malignant breast masses and subjective interpretation. PURPOSE: To evaluate the performance of conductivity imaging for reducing false-positive biopsy results related to breast US, as compared to diffusion-weighted imaging (DWI) and abbreviated MRI consisting of one pre- and one post-contrast T1-weighted imaging. STUDY TYPE: Prospective. SUBJECTS: Seventy-nine women (median age, 44 years) with 86 Breast Imaging Reporting and Data System (BI-RADS) category 4 masses as detected by breast US. FIELD STRENGTH/SEQUENCE: 3-T, T2-weighted turbo spin echo sequence, DWI, and abbreviated contrast-enhanced MRI (T1-weighted gradient echo sequence). ASSESSMENT: US-guided biopsy (reference standard) was obtained on the same day as MRI. The maximum and mean conductivity parameters from whole and single regions of interest (ROIs) were measured. Apparent diffusion coefficient (ADC) values were obtained from an area with the lowest signal within a lesion on the ADC map. The performance of conductivity, ADC, and abbreviated MRI for reducing false-positive biopsies was evaluated using the following criteria: lowest conductivity and highest ADC values among malignant breast lesions and BI-RADS categories 2 or 3 on abbreviated MRI. STATISTICAL TESTS: One conductivity parameter with the maximum area under the curve (AUC) from receiver operating characteristics was selected. A P-value <0.05 was considered statistically significant. RESULTS: US-guided biopsy revealed 65 benign lesions and 21 malignant lesions. The mean conductivity parameter of the single ROI method was selected (AUC = 0.74). Considering conductivity (≤0.10 S/m), ADC (≥1.60 × 10-3 mm2 /sec), and BI-RADS categories 2 or 3 reduced false-positive biopsies by 23% (15 of 65), 38% (25 of 65), and 43% (28 of 65), respectively, without missing malignant lesions. DATA CONCLUSION: Conductivity imaging may show lower performance than DWI and abbreviated MRI in reducing unnecessary biopsies. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 2.

5.
Theriogenology ; 209: 213-223, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37437338

RESUMO

Extracellular vesicles (EVs) play an active role in regulating different physiological events, however, endocrine control of EVs cargo contents remain poorly understood. In this study, we aimed to isolate EVs from the porcine oviductal epithelial cells (POECs) that were primed with steroid hormones including estradiol (E2) and progesterone (P4), mimicking the in vivo conditions of the reproductive cycle and studied their effects on in vitro produced embryonic development. For this purpose, POECs were treated either with 0 concentration (control) or two different combinations of E2 and P4 including 50 pg/mL E2 + 0.5 ng/mL P4 (group H1), and 10 pg/mL E2 + 35 ng/mL P4 (group H2). Embryos were prepared after in vitro maturation either by parthenogenetic activation or somatic cell nuclear transfer (SCNT) technique. Treating parthenogenetic embryo with EVs, led a significantly higher rate of the blastocyst formation in the group supplemented with each EVs, compared to the control group. In addition, TUNEL assay and gene expression level analysis revealed that apoptosis was significantly reduced in the H2 EVs group. Furthermore, EVs from hormone-primed POECs improved the formation rate of porcine SCNT embryos compared to the control group. While in each EVs supplemented group (control EVs, H1 EVs, H2 EVs), the expression of cell reprogramming-related genes in cloned embryos showed a tendency of increase, the effect was stronger in H1 EVs and H2 EVs. In conclusion, EVs derived from POECs cultured in hormonal conditions simulating the in vivo environment had a positive effect on porcine blastocysts formation, which will likely facilitate in the production of cloned embryos.


Assuntos
Desenvolvimento Embrionário , Vesículas Extracelulares , Feminino , Gravidez , Suínos , Animais , Partenogênese , Técnicas de Transferência Nuclear/veterinária , Progesterona/farmacologia , Progesterona/metabolismo , Células Epiteliais , Blastocisto/fisiologia
6.
Hum Brain Mapp ; 44(15): 4986-5001, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37466309

RESUMO

Magnetic resonance electrical properties tomography (MR-EPT) is a non-invasive measurement technique that derives the electrical properties (EPs, e.g., conductivity or permittivity) of tissues in the radiofrequency range (64 MHz for 1.5 T and 128 MHz for 3 T MR systems). Clinical studies have shown the potential of tissue conductivity as a biomarker. To date, model-based conductivity reconstructions rely on numerical assumptions and approximations, leading to inaccuracies in the reconstructed maps. To address such limitations, we propose an artificial neural network (ANN)-based non-linear conductivity estimator trained on simulated data for conductivity brain imaging. Network training was performed on 201 synthesized T2-weighted spin-echo (SE) data obtained from the finite-difference time-domain (FDTD) electromagnetic (EM) simulation. The dataset was composed of an approximated T2-w SE magnitude and transceive phase information. The proposed method was tested three in-silico and in-vivo on two volunteers and three patients' data. For comparison purposes, various conventional phase-based EPT reconstruction methods were used that ignore B 1 + magnitude information, such as Savitzky-Golay kernel combined with Gaussian filter (S-G Kernel), phase-based convection-reaction EPT (cr-EPT), magnitude-weighted polynomial-fitting phase-based EPT (Poly-Fit), and integral-based phase-based EPT (Integral-based). From the in-silico experiments, quantitative analysis showed that the proposed method provides more accurate and improved quality (e.g., high structural preservation) conductivity maps compared to conventional reconstruction methods. Representatively, in the healthy brain in-silico phantom experiment, the proposed method yielded mean conductivity values of 1.97 ± 0.20 S/m for CSF, 0.33 ± 0.04 S/m for WM, and 0.52 ± 0.08 S/m for GM, which were closer to the ground-truth conductivity (2.00, 0.30, 0.50 S/m) than the integral-based method (2.56 ± 2.31, 0.39 ± 0.12, 0.68 ± 0.33 S/m). In-vivo ANN-based conductivity reconstructions were also of improved quality compared to conventional reconstructions and demonstrated network generalizability and robustness to in-vivo data and pathologies. The reported in-vivo brain conductivity values were in agreement with literatures. In addition, the proposed method was observed for various SNR levels (SNR levels = 10, 20, 40, and 58) and repeatability conditions (the eight acquisitions with the number of signal averages = 1). The preliminary investigations on brain tumor patient datasets suggest that the network trained on simulated dataset can generalize to unforeseen in-vivo pathologies, thus demonstrating its potential for clinical applications.


Assuntos
Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Condutividade Elétrica , Imagens de Fantasmas , Neuroimagem , Algoritmos
7.
Sci Rep ; 13(1): 9844, 2023 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-37330544

RESUMO

We investigated the correlation between standardized uptake value (SUV) of 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) and conductivity parameters in breast cancer and explored the feasibility of conductivity as an imaging biomarker. Both SUV and conductivity have the potential to reflect the tumors' heterogeneous characteristics, but their correlations have not been investigated until now. Forty four women diagnosed with breast cancer who underwent breast MRI and 18F-FDG PET/CT at the time of diagnosis were included. Among them, 17 women received neoadjuvant chemotherapy followed by surgery and 27 women underwent upfront surgery. For conductivity parameters, maximum and mean values of the tumor region-of-interests were examined. For SUV parameters, SUVmax, SUVmean, and SUVpeak of the tumor region-of-interests were examined. Correlations between conductivity and SUV were evaluated, and among them, the highest correlation was observed between mean conductivity and SUVpeak (Spearman's correlation coefficient = 0.381). In a subgroup analysis for 27 women with upfront surgery, tumors with lymphovascular invasion (LVI) showed higher mean conductivity than those without LVI (median: 0.49 S/m vs 0.06 S/m, p < 0.001). In conclusion, our study shows a low positive correlation between SUVpeak and mean conductivity in breast cancer. Furthermore, conductivity showed a potential to noninvasively predict LVI status.


Assuntos
Neoplasias da Mama , Fluordesoxiglucose F18 , Humanos , Feminino , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Compostos Radiofarmacêuticos/uso terapêutico , Prognóstico , Tomografia por Emissão de Pósitrons/métodos
8.
Exp Mol Med ; 55(6): 1218-1231, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37258579

RESUMO

The signaling pathways governing acetaminophen (APAP)-induced liver injury have been extensively studied. However, little is known about the ubiquitin-modifying enzymes needed for the regulation of APAP-induced liver injury. Here, we examined whether the Pellino3 protein, which has E3 ligase activity, is needed for APAP-induced liver injury and subsequently explored its molecular mechanism. Whole-body Peli3-/- knockout (KO) and adenovirus-mediated Peli3 knockdown (KD) mice showed reduced levels of centrilobular cell death, infiltration of immune cells, and biomarkers of liver injury, such as alanine aminotransferase (ALT) and aspartate aminotransferase (AST), upon APAP treatment compared to wild-type (WT) mice. Peli3 deficiency in primary hepatocytes decreased mitochondrial and lysosomal damage and reduced the mitochondrial reactive oxygen species (ROS) levels. In addition, the levels of phosphorylation at serine 9 in the cytoplasm and mitochondrial translocation of GSK3ß were decreased in primary hepatocytes obtained from Peli3-/- KO mice, and these reductions were accompanied by decreases in JNK phosphorylation and mitochondrial translocation. Pellino3 bound more strongly to GSK3ß compared with JNK1 and JNK2 and induced the lysine 63 (K63)-mediated polyubiquitination of GSK3ß. In rescue experiments, the ectopic expression of wild-type Pellino3 in Peli3-/- KO hepatocytes restored the mitochondrial translocation of GSK3ß, but this restoration was not obtained with expression of a catalytically inactive mutant of Pellino3. These findings are the first to suggest a mechanistic link between Pellino3 and APAP-induced liver injury through the modulation of GSK3ß polyubiquitination.


Assuntos
Acetaminofen , Doença Hepática Crônica Induzida por Substâncias e Drogas , Animais , Camundongos , Acetaminofen/efeitos adversos , Fosforilação , Glicogênio Sintase Quinase 3 beta/genética , Glicogênio Sintase Quinase 3 beta/metabolismo , Doença Hepática Crônica Induzida por Substâncias e Drogas/metabolismo , Fígado/metabolismo , Hepatócitos/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Camundongos Endogâmicos C57BL
9.
Nat Commun ; 14(1): 2980, 2023 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-37221214

RESUMO

Although T cell activation is known to involve the internalization of the T cell antigen receptor (TCR), much less is known regarding the release of TCRs following T cell interaction with cognate antigen-presenting cells. In this study, we examine the physiological mechanisms underlying TCR release following T cell activation. We show that T cell activation results in the shedding of TCRs in T cell microvilli, which involves a combined process of trogocytosis and enzymatic vesiculation, leading to the loss of membrane TCRs and microvilli-associated proteins and lipids. Surprisingly, unlike TCR internalization, this event results in the rapid upregulation of surface TCR expression and metabolic reprogramming of cholesterol and fatty acid synthesis to support cell division and survival. These results demonstrate that TCRs are lost through trogocytic 'molting' following T cell activation and highlight this mechanism as an important regulator of clonal expansion.


Assuntos
Receptores de Antígenos de Linfócitos T , Linfócitos T , Microvilosidades , Membrana Celular , Adipogenia
10.
J Phys Chem Lett ; 14(13): 3329-3334, 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-36989527

RESUMO

We employed the chemical potential equalization principle to demonstrate that fractional electrons are involved in the electro-inductive effect as well as the vibrational Stark effect. By the chemical potential model, we were able to deduce that the frontier molecular orbitals of immobilized molecules can provide valuable insight into these effects. To further understand and quantify these findings, we introduced fractional charge density functional theory (FC-DFT), a canonical ensemble approach for open systems. This method allows for the calculation of electronic energies, nuclear gradients, and the Hessian matrix of fractional electronic systems. To correct the spurious delocalization error commonly found in approximate density functionals for small systems, we imposed the Perdew-Parr-Levy-Balduz (PPLB) condition through linear interpolation of two adjacent integer points (LI-FC-DFT). Although this approach is relatively simple in terms of molecular modeling, the results obtained through LI-FC-DFT calculations predict the same trend seen in experimental reactivity and the frequency change of immobilized molecules.

11.
Med Phys ; 50(3): 1660-1669, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36585806

RESUMO

BACKGROUND: Phase-based electrical property tomography (EPT) is a technique that allows conductivity reconstruction with only phase of the B1 field under the assumption that the magnitude of the B1 fields are homogeneous. The more this assumption is violated, the less accurate the reconstructed conductivity. Thus, a method that ensures homogeneity of | B 1 - | $| {{\rm{B}}_1^ - } |$ field is important for breast image using multi-receiver coil. PURPOSE: To develop a method for multi-receiver combination for phase-based EPT usable for breast EPT imaging in the clinic. METHODS: Theory of the proposed method is presented. To validate the proposed method, the phantom and in-vivo experiments were conducted. Conductivity images were reconstructed using the transceive phase of the combined image and results were compared with another combination method. RESULTS: The proposed method's conductivity results were more stable than those of the previous method when | B 1 + | $| {{\rm{B}}_1^ + } |$ was not homogeneous and when the homogeneous contrast region was small. The phantom and in-vivo results indicate that the proposed method produces improved conductivity images than the previous method. The proposed combination method also increased the conductivity contrast between benign and cancerous tissues. CONCLUSION: The proposed method produced more stable multi-receiver combination for phase-based EPT of the breast in a clinical environment.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Imageamento por Ressonância Magnética/métodos , Algoritmos , Tomografia/métodos , Condutividade Elétrica , Imagens de Fantasmas , Processamento de Imagem Assistida por Computador/métodos
12.
Chemistry ; 29(14): e202203128, 2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36447369

RESUMO

The cationic complex [Ni(H)(OH)]+ was previously found to activate dioxygen and methane in gas phase under single collision conditions. These remarkable reactivities were thought to originate from a non-classical electronic structure, where the Ni-center adopts a Ni(II), instead of the classically expected Ni(III) oxidation state by formally accepting an electron from the hydroxo ligand, which formally becomes a hydroxyl radical in the process. Such radicaloid oxygen moieties are envisioned to easily react with otherwise inert substrates, mimicking familiar reactivities of free radicals. In this study, the reductive activation of dioxygen by [Ni(H)(OH)]+ to afford the hydroperoxo species was investigated using coupled cluster, multireference ab initio and density functional theory calculations. Orbital and wave function analyses indicate that O2 binding tranforms the aforementioned non-classical electronic structure to a classical Ni(III)-hydroxyl system, before O2 reduction takes place. Remarkably, we found no evidence for a direct involvement of the radicaloid hydroxyl in the reaction with O2 , as is often assumed. The function of the redox non-innocent character of the activator complex is to protect the reactive electronic structure until the complex engages O2 , upon which a dramatic electronic reorganization releases internal energy and drives the chemical reaction to completion.

13.
Materials (Basel) ; 17(1)2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38203907

RESUMO

The cement industry emits a significant amount of carbon dioxide (CO2). Therefore, the cement industry should recycle the emitted CO2. However, sequestration by carbonation in cement composites absorbs a very small amount of CO2. Therefore, a direct way of achieving this is to improve the absorption performance of CO2 in cement composites. In this study, to improve absorption, unlike in existing studies, a granulation technique was applied, and the material used was calcium hydroxide (CH). In addition, granulated CH was coated to prevent a reaction during the curing of cement paste. The coated CH granule (CCHG) was applied to 5% of the cement weight as an additive material, and the specimens were cured for 91 days to wait for the coating of CCHG to fully phase-change. The experiment of CO2 absorption showed an unexpected result, where the use of blast furnace slag (BFS) and fly ash (FA) had a negative effect on CO2 sequestration. This was because BFS and FA had a filler effect in the cement matrix, and the filler effect caused the blocking of the path of CO2. In addition, BFS and FA are well-known pozzolanic materials; the pozzolan reaction caused a reduction in the amount of CH because the pozzolan reaction consumed the CH to produce a calcium silicate hydrate. Therefore, the pozzolan reaction also had a negative effect on the CO2 sequestration performance combined with the filler effect. The CO2 sequestration efficiency was decreased between ordinary cement paste and BFS-applied specimens by 45.45%. In addition, compared to cases of ordinary cement paste and FA-applied specimens, the CO2 sequestration performance was decreased by 63.64%. Comprehensively, CO2 sequestration performance depends on the porosity and amount of CH.

14.
Chem Commun (Camb) ; 58(77): 10793-10796, 2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36073243

RESUMO

Through the application of a redox-innocent aryl diimine chelate, the discovery and utilization of a cobalt catalyst, (Ph2PPrADI)Co, that exhibits carbonyl hydrosilylation turnover frequencies of up to 330 s-1 is described. This activity is believed to be the highest ever reported for metal-catalyzed carbonyl hydrosilylation.

15.
J Am Chem Soc ; 144(29): 13066-13070, 2022 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-35833652

RESUMO

Highly modular and rational syntheses of titanium compounds containing ditelluride, terminal telluride, and bis(telluride) structural motifs are disclosed in this study. Titanate anions bearing two cis and terminal telluride functionalities bound to the same metal center represent a unique example of a group 4 transition metal bis(chalcogenide) ion and are accessed in a simple, single-step procedure from Ti(III) bis(alkyl) complexes in the presence of an outer-sphere reductant and at least 3 equiv of Te0 powder. These compounds have been characterized crystallographically and spectroscopically with some preliminary reactivity reported for the anionic Ti(═Te)2 motif. We also report solution 125Te NMR spectral data in addition to theoretical studies addressing the bonding and structure for these titanate bis(tellurido) systems.


Assuntos
Compostos Organometálicos , Titânio , Espectroscopia de Ressonância Magnética , Metais , Compostos Organometálicos/química , Titânio/química
16.
Med Phys ; 49(9): 5929-5942, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35678751

RESUMO

PURPOSE: To enable acceleration in 3D multi-echo gradient echo (mGRE) acquisition for myelin water imaging (MWI) by combining joint parallel imaging (JPI) and joint deep learning (JDL). METHODS: We implemented a multistep reconstruction process using both advanced parallel imaging and deep learning network which can utilize joint spatiotemporal components between the multi-echo images to further accelerate 3D mGRE acquisition for MWI. In the first step, JPI was performed to estimate missing k-space lines. Next, JDL was implemented to reduce residual artifacts and produce high-fidelity reconstruction by using variable splitting optimization consisting of spatiotemporal denoiser block, data consistency block, and weighted average block. The proposed method was evaluated for MWI with 2D Cartesian uniform under-sampling for each echo, enabling scan times of up to approximately 2 min for 2 mm × 2 mm × 2 mm $2\ {\rm mm} \times 2\ {\rm mm} \times 2\ {\rm mm}$ 3D coverage. RESULTS: The proposed method showed acceptable MWI quality with improved quantitative values compared to both JPI and JDL methods individually. The improved performance of the proposed method was demonstrated by the low normalized mean-square error and high-frequency error norm values of the reconstruction with high similarity to the fully sampled MWI. CONCLUSION: Joint spatiotemporal reconstruction approach by combining JPI and JDL can achieve high acceleration factors for 3D mGRE-based MWI.


Assuntos
Imageamento por Ressonância Magnética , Bainha de Mielina , Encéfalo , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X , Água
17.
Inorg Chem ; 61(17): 6438-6450, 2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-35438990

RESUMO

It was recently discovered that (Ph2PPrPDI)Mn (PDI = pyridine diimine) exists as a superposition of low-spin Mn(II) that is supported by a PDI dianion and intermediate-spin Mn(II) that is antiferromagnetically coupled to a triplet PDI dianion, a finding that encouraged the synthesis and electronic structure evaluation of late first row metal variants that feature the same chelate. The addition of Ph2PPrPDI to FeBr2 resulted in bromide dissociation and the formation of [(Ph2PPrPDI)FeBr][Br]. Reduction of this precursor using excess sodium amalgam afforded (Ph2PPrPDI)Fe, which possesses an Fe(II) center that is supported by a dianionic PDI ligand. Similarly, reduction of a premixed solution of Ph2PPrPDI and CoCl2 yielded the cobalt analog, (Ph2PPrPDI)Co. EPR spectroscopy and density functional theory calculations revealed that this compound features a high-spin Co(I) center that is antiferromagnetically coupled to a PDI radical anion. The addition of Ph2PPrPDI to Ni(COD)2 resulted in ligand displacement and the formation of (Ph2PPrPDI)Ni, which was found to possess a pendent phosphine group. Single-crystal X-ray diffraction, CASSCF calculations, and EPR spectroscopy indicate that (Ph2PPrPDI)Ni is best described as having a Ni(II)-PDI2- configuration. The electronic differences between these compounds are highlighted, and a computational analysis of Ph2PPrPDI denticity has revealed the thermodynamic penalties associated with phosphine dissociation from 5-coordinate (Ph2PPrPDI)Mn, (Ph2PPrPDI)Fe, and (Ph2PPrPDI)Co.


Assuntos
Cobalto , Ferro , Cobalto/química , Eletrônica , Ferro/química , Ligantes , Níquel , Oxirredução , Fosfinas , Piridinas/química
18.
Int J Chron Obstruct Pulmon Dis ; 16: 3083-3091, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34803377

RESUMO

INTRODUCTION: Few studies have examined the prevalence and associated factors of early chronic obstructive pulmonary disease (COPD) in Asians. OBJECTIVE: To evaluate the prevalence of early COPD and its associated factors among non-institutionalized middle-aged Korean adults. METHODS: A total of 3195 participants aged 40-49 years from the 2016-2018 Korea National Health and Nutrition Examination Survey were included in this study. Patients (1) aged less than 50 years, (2) with a minimum of 10 pack-years of smoking, and (3) with forced expiratory volume in 1 s/forced vital capacity (FEV1/FVC) below the lower limit of normal were diagnosed with early COPD. The prevalence and odds ratio (OR) for early COPD were measured using multivariate logistic regression analysis, and the demographic data, anthropometric measurements, socioeconomic status, and lifestyle factors were considered covariates. RESULTS: The overall prevalence of early COPD among the middle-aged Korean population was 2.4% (4.4% in men and 0.4% in women), while that in participants with ≥10 pack-years was 8.2% (8.1% in men and 11.3% in women). A multivariate logistic regression model showed that male sex, urban residence, chronic sputum production, and hypertriglyceridemia were associated with increased ORs for early COPD in middle-aged, non-institutionalized Korean adults. CONCLUSION: Early COPD is prevalent among middle-aged smokers in Korea. Efforts are needed to reduce the potential negative effects of early COPD on public health in Korea and other Asian countries.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Adulto , Feminino , Volume Expiratório Forçado , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Prevalência , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Fatores de Risco , Espirometria , Capacidade Vital
19.
Front Immunol ; 12: 711847, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34484214

RESUMO

Severe fever with thrombocytopenia syndrome (SFTS) is a new tick-borne viral disease, and most SFTS virus (SFTSV) infections occur via bites from the tick Haemaphysalis longicornis; however, SFTSV transmission can also occur through close contact with an infected patient. SFTS is characterized by acute high fever, thrombocytopenia, leukopenia, elevated serum hepatic enzyme levels, gastrointestinal symptoms, and multiorgan failure and has a 16.2 to 30% mortality rate. In this study, we found that age, dyspnea rates, aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase, multiorgan dysfunction score (MODS), viral load, IL-6 levels, and IL-10 levels were higher in patients with fatal disease than in patients with nonfatal disease during the initial clinical course of SFTS. In addition, we found that IL-6 and IL-10 levels, rather than viral load and neutralizing antibody titers, in patients with an SFTSV infection strongly correlated with outcomes (for severe disease with an ultimate outcome of recovery or death).


Assuntos
Interleucina-10/sangue , Interleucina-6/sangue , Febre Grave com Síndrome de Trombocitopenia/imunologia , Viremia/imunologia , Idoso , Idoso de 80 Anos ou mais , Alanina Transaminase/sangue , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Aspartato Aminotransferases/sangue , Citocinas/sangue , Dispneia/etiologia , Feminino , Humanos , Interleucina-10/fisiologia , Interleucina-6/fisiologia , L-Lactato Desidrogenase/sangue , Masculino , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos/etiologia , Insuficiência de Múltiplos Órgãos/mortalidade , Phlebovirus/imunologia , República da Coreia/epidemiologia , Febre Grave com Síndrome de Trombocitopenia/sangue , Febre Grave com Síndrome de Trombocitopenia/mortalidade , Febre Grave com Síndrome de Trombocitopenia/virologia , Resultado do Tratamento , Carga Viral , Viremia/sangue , Viremia/mortalidade
20.
Tissue Eng Regen Med ; 18(6): 941-951, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34495501

RESUMO

BACKGROUND: We aimed to validate a pilot study of photodiagnosis using near infrared (NIR) transillumination and assess the clinical efficacy of hypericin-mediated photodynamic therapy (HYP-PDT) in a rabbit laryngeal cancer model in order to develop a novel therapeutic modality with complete remission and preservation of the functional organ. METHODS: (1) In vitro study: VX tumor cells were subcultured and subjected to HYP-PDT. (2) In vivo study: A laryngeal cancer model was developed in which 12 rabbits were inoculated with a VX tumor suspension in the submucosal area of the left vocal fold using a transoral approach. All rabbits underwent NIR transillumination using light with a wavelength of 780 nm. The survival periods of the three treatment groups (6 rabbits in Group A: HYP-PDT, 3 each in Groups B and C: laser irradiation or HYP administration only) were analyzed. RESULTS: The higher the HYP concentration, the lower the VX cell viability in response to HYP-PDT using 590 nm LED. Following HYP-PDT, small tumors in Group A-1 rabbits healed completely and the animals demonstrated a long survival period, and larger tumors in Group A-2 healed partially with a survival period that extended over 3 weeks after inoculation. The survival of Groups B and C were not different over the first 3 weeks of the study, and were shorter than in Group A. CONCLUSION: We found HYP-PDT could be a curative therapy for early-stage cancers that may also preserve organ function, and may inhibit tumor progression and metastasis during advanced stages of laryngeal cancer.


Assuntos
Neoplasias Laríngeas , Fotoquimioterapia , Animais , Antracenos , Neoplasias Laríngeas/tratamento farmacológico , Perileno/análogos & derivados , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Projetos Piloto , Coelhos , Transiluminação
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