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1.
Lipids Health Dis ; 23(1): 106, 2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38616260

RESUMO

BACKGROUND: Dyslipidemia, a significant risk factor for atherosclerotic cardiovascular disease (ASCVD), is influenced by genetic variations, particularly those in the low-density lipoprotein receptor (LDLR) gene. This study aimed to elucidate the effects of LDLR polymorphisms on baseline serum lipid levels and the therapeutic efficacy of atorvastatin in an adult Han population in northern China with dyslipidemia. METHODS: In this study, 255 Han Chinese adults receiving atorvastatin therapy were examined and followed up. The 3' untranslated region (UTR) of the LDLR gene was sequenced to identify polymorphisms. The associations between gene polymorphisms and serum lipid levels, as well as changes in lipid levels after intervention, were evaluated using the Wilcoxon rank sum test, with a P < 0.05 indicating statistical significance. Assessment of linkage disequilibrium patterns and haplotype structures was conducted utilizing Haploview. RESULTS: Eleven distinct polymorphisms at LDLR 3' UTR were identified. Seven polymorphisms (rs1433099, rs14158, rs2738466, rs5742911, rs17249057, rs55971831, and rs568219285) were correlated with the baseline serum lipid levels (P < 0.05). In particular, four polymorphisms (rs14158, rs2738466, rs5742911, and rs17249057) were in strong linkage disequilibrium (r2 = 1), and patients with the AGGC haplotype had higher TC and LDL-C levels at baseline. Three polymorphisms (rs1433099, rs2738467, and rs7254521) were correlated with the therapeutic efficacy of atorvastatin (P < 0.05). Furthermore, carriers of the rs2738467 T allele demonstrated a significantly greater reduction in low-density lipoprotein cholesterol (LDL-C) levels post-atorvastatin treatment (P = 0.03), indicating a potentially crucial genetic influence on therapeutic outcomes. Two polymorphisms (rs751672818 and rs566918949) were neither correlated with the baseline serum lipid levels nor atorvastatin's efficacy. CONCLUSIONS: This research outlined the complex genetic architecture surrounding LDLR 3' UTR polymorphisms and their role in lipid metabolism and the response to atorvastatin treatment in adult Han Chinese patients with dyslipidemia, highlighting the importance of genetic profiling in enhancing tailored therapeutic strategies. Furthermore, this investigation advocates for the integration of genetic testing into the management of dyslipidemia, paving the way for customized therapeutic approaches that could significantly improve patient care. TRIAL REGISTRATION: This multicenter study was approved by the Ethics Committee of Xiangya Hospital Central South University (ethics number K22144). It was a general ethic. In addition, this study was approved by The First Hospital of Hebei Medical University (ethics number 20220418).


Assuntos
Dislipidemias , Polimorfismo Genético , Adulto , Humanos , Atorvastatina/uso terapêutico , Regiões 3' não Traduzidas/genética , LDL-Colesterol , Dislipidemias/tratamento farmacológico , Dislipidemias/genética , China
2.
Appl Opt ; 63(5): 1258-1264, 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38437305

RESUMO

Lead halide perovskites (LHPs) have been extensively studied due to their remarkable optoelectronic performance. However, the toxicity of a lead ion to humans and its instability under ambient conditions render lead-based halide perovskite an unsuitable material for commercialization. Meanwhile, lead-free halide perovskite (LFHP) devices generally exhibit poor performance. Therefore, enhancing photoelectric conversion capacity is the most important issue that needs to be addressed. Here, we propose a photodetector (PD) fabricated using C s B i 3 I 10/p h e n y l-C 61-butyric acid methyl ester (PCBM) bulk heterojunction as the active layer. The PD illuminated under 532 nm can reach a high responsivity (1.54 A/W) at -2V bias, while at 2 V bias, the PD reaches a higher responsivity (224.40 A/W). All of those results suggest that C s B i 3 I 10/P C B M bulk heterojunctions hold enormous potential in substituting for LHPs in optoelectronic devices.

3.
Materials (Basel) ; 17(4)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38399066

RESUMO

Cu-Be alloys exhibit excellent comprehensive performance in electrics, thermotics, and mechanics, and hence, they attract much attention. Among them, low-Be copper alloys are more environmentally friendly and promising. This study explores the effects of different Ni contents and heat treatment parameters on the properties, microstructures, and precipitates of Cu-0.2 wt% Be-x wt% Ni (0 < x < 2.0) alloys. The experimental results demonstrate that the fast cooling rate of cast alloys during solidification contributes to retention of the solute atoms in the copper matrix, which is beneficial for subsequent solid solution treatment. Furthermore, solid solution treatment slightly reduces the electrical conductivities, microhardness values, and compressive yield strengths of Cu-0.2 wt% Be-1.0/1.6 wt% Ni alloys. The optimal solution temperature and time are about 925 ℃ and 60 min, respectively. Aging treatment significantly increases the electrical conductivities, microhardness values, and compressive yield strengths of Cu-0.2 wt% Be-1.0/1.6 wt% Ni alloys. The best aging temperature is around 450 ℃. However, the properties of Cu-0.2 wt%Be-0.4 wt%Ni alloys remain unaffected by solution and aging treatments. Around x = 1.0, Cu-0.2 wt% Be-x wt% Ni alloys possess the best comprehensive properties, which are about 72%IACS of electrical conductivity, 241 HV of microhardness, and 281MPa of compressive yield strength, respectively. TEM and EDS analyses reveal that the precipitate evolution of Cu-0.2 wt% Be-1.0 wt% Ni alloys with aging time is GP zones → γ″ → γ'. Notably, a distinct double-peak age strengthening phenomenon emerges with Cu-0.2 wt% Be-1.0/1.6 wt% Ni alloys. The precipitation of plenty of GP zones at the early stage of aging should account for the first strengthening peak, and the strengthening mechanism transformation of the γ″ or γ' phase from shear to Orowan should induce the second strengthening peak. This work may help to design new low-Be copper alloys and their preparation processes.

4.
PeerJ ; 12: e16898, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38332807

RESUMO

Agrobacterium tumefaciens is a soil-borne pathogenic bacterium that causes crown gall disease in many plants. Chemotaxis offers A. tumefaciens the ability to find its host and establish infection. Being an aerobic bacterium, A. tumefaciens possesses one chemotaxis system with multiple potential chemoreceptors. Chemoreceptors play an important role in perceiving and responding to environmental signals. However, the studies of chemoreceptors in A. tumefaciens remain relatively restricted. Here, we characterized a cytoplasmic chemoreceptor of A. tumefaciens C58 that contains an N-terminal globin domain. The chemoreceptor was designated as Atu1027. The deletion of Atu1027 not only eliminated the aerotactic response of A. tumefaciens to atmospheric air but also resulted in a weakened chemotactic response to multiple carbon sources. Subsequent site-directed mutagenesis and phenotypic analysis showed that the conserved residue His100 in Atu1027 is essential for the globin domain's function in both chemotaxis and aerotaxis. Furthermore, deleting Atu1027 impaired the biofilm formation and pathogenicity of A. tumefaciens. Collectively, our findings demonstrated that Atu1027 functions as an aerotaxis receptor that affects agrobacterial chemotaxis and the invasion of A. tumefaciens into its host.


Assuntos
Agrobacterium tumefaciens , Quimiotaxia , Agrobacterium tumefaciens/genética , Quimiotaxia/genética , Tumores de Planta/microbiologia , Plantas , Globinas
5.
Eur J Cardiothorac Surg ; 65(1)2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38175783

RESUMO

OBJECTIVES: The aim of this study was to explore the prognostic value of brain computed tomography perfusion (CTP) for postoperative new stroke in acute type A aortic dissection (ATAAD) patients. METHODS: Patients with ATAAD and suspected cerebral malperfusion who underwent brain CTP and surgical repair were retrospectively analysed. Brain perfusion was quantified mainly with the averaged cerebral blood flow. Significant clinical and imaging findings were identified through univariable and multivariable regression analysis. Furthermore, the added prognostic benefit of perfusion parameters was confirmed with the receiver operating characteristic curves in the entire cohort and subgroup analysis. RESULTS: The incidence of postoperative new stroke was 30.8% (44/143). The independent adjusted predictors of postoperative new stroke included an impaired averaged cerebral blood flow (ml/100 ml/min) (odds ratio: 0.889; P < 0.001), severe stenosis (odds ratio: 5.218; P = 0.011) or occlusion (odds ratio: 14.697; P = 0.048) of the true lumen in common carotid artery (CCA), hypotension on admission (odds ratio: 9.644; P = 0.016) and a longer surgery time (odds ratio: 1.593; P = 0.021). The area under the receiver operating characteristic curves significantly improved after adding perfusion parameters to clinical and computed tomography angiography characteristics (P = 0.048). This benefit was more pronounced in patients with severe stenosis or occlusion in CCA true lumen (P = 0.004). CONCLUSIONS: Brain CTP could be a useful prognostic tool for surgically treated ATAAD patients and especially beneficial in patients with severe stenosis or occlusion of the CCA true lumen.


Assuntos
Dissecção Aórtica , Acidente Vascular Cerebral , Humanos , Estudos Retrospectivos , Constrição Patológica , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/cirurgia , Prognóstico , Encéfalo , Tomografia Computadorizada por Raios X , Acidente Vascular Cerebral/terapia , Perfusão , Resultado do Tratamento
6.
Chirality ; 36(2): e23634, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38057950

RESUMO

To investigate the thermodynamic and molecular self-assembly mechanism of trans-1,2-cyclohexane dicarboxylic acid containing two carboxylic acid groups in the chiral resolution process, (S)-phenylethylamine was used as the chiral resolving agent. Two stoichiometric salts were formed when the raw materials were fed at different molar ratios: cyclohexane dicarboxylate monophenylethylamine salt and cyclohexane dicarboxylate diphenylethylamine salt. When the molar ratio of the (S)-phenylethylamine to trans-1,2-cyclohexane dicarboxylic acid was less than 3:1, trans-(1S,2S)-cyclohexane dicarboxylic acid was obtained with 97 e.e% purity. But when the molar ratio exceeded 3:1, the product was the racemic trans-(1,2)-cyclohexane dicarboxylic acid. In addition, single crystal structures of more soluble mono-salt, less soluble mono-salt, and less soluble di-salt were obtained. The weak intermolecular interactions and the way of the molecules packing in the crystals were analyzed. The hydrogen bond was stronger in the less soluble salt than that in the more soluble salt. And a "lock-and-key" structure in the hydrophobic layers makes it more tightly packed through the van der Waals interaction, which is responsible for the stability of less soluble salts.

7.
Acad Radiol ; 2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38160090

RESUMO

RATIONALE AND OBJECTIVES: Pericoronary adipose tissue (PCAT) CT attenuation of right coronary artery (RCA) and non-alcoholic fatty liver disease (NAFLD) have prognostic value for major adverse cardiovascular events (MACE) in patients with coronary artery disease. However, the superior prognostic value between RCA PCAT CT attenuation and NAFLD remains unclear in patients with acute chest pain. This study is to evaluate the prognostic value of NAFLD for MACE, and further assess the incremental prognostic value of NAFLD over PCAT CT attenuation. MATERIALS AND METHODS: Between January 2011 and December 2021, all consecutive emergency patients with acute chest pain referred for coronary CT angiography (CCTA) were retrospectively enrolled. MACE included unstable angina requiring hospitalization, coronary revascularization, non-fatal myocardial infarction, and all-cause death. Patients' baseline and CCTA characteristics, RCA PCAT CT attenuation, and the presence of NAFLD were used to evaluate risk factors of MACE using multivariable Cox regression analysis. The prognostic value of NAFLD compared to RCA PCAT CT attenuation was analyzed. RESULTS: A total of 514 patients were enrolled (mean age, 58.36 ± 13.05 years; 310 men). During a median follow-up of 31 months, 60 patients (11.67%) experienced MACE. NAFLD (HR = 2.599, 95% CI: 1.207, 5.598, P = 0.015) and RCA PCAT CT attenuation (HR = 1.026, 95% CI: 1.001, 1.051, P = 0.038) were independent predictors of MACE. The global Chi-square analysis showed that NAFLD improved the risk of MACE more than that using clinical risk factors and CCTA metrics (59.51 vs 54.44, P = 0.024) or combined with RCA PCAT CT attenuation (63.75 vs 59.51, P = 0.040). CONCLUSION: NAFLD and RCA PCAT CT attenuation were predictors of MACE. NAFLD had an incremental prognostic value beyond RCA PCAT CT attenuation for MACE in patients with acute chest pain. Adding CT-FFR into the risk prediction of patients with acute chest pain is worth considering.

8.
Front Endocrinol (Lausanne) ; 14: 1239502, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37916150

RESUMO

Background: Aging is an inescapable process, but it can be slowed down, particularly facial aging. Sex and growth hormones have been shown to play an important role in the process of facial aging. We investigated this association further, using a two-sample Mendelian randomization study. Methods: We analyzed genome-wide association study (GWAS) data from the UK Biobank database comprising facial aging data from 432,999 samples, using two-sample Mendelian randomization. In addition, single-nucleotide polymorphism (SNP) data on sex hormone-binding globulin (SHBG) and sex steroid hormones were obtained from a GWAS in the UK Biobank [SHBG, N = 189,473; total testosterone (TT), N = 230,454; bioavailable testosterone (BT), N = 188,507; and estradiol (E2), N = 2,607)]. The inverse-variance weighted (IVW) method was the major algorithm used in this study, and random-effects models were used in cases of heterogeneity. To avoid errors caused by a single algorithm, we selected MR-Egger, weighted median, and weighted mode as supplementary algorithms. Horizontal pleiotropy was detected based on the intercept in the MR-Egger regression. The leave-one-out method was used for sensitivity analysis. Results: SHBG plays a promoting role, whereas sex steroid hormones (TT, BT, and E2) play an inhibitory role in facial aging. Growth hormone (GH) and insulin-like growth factor-1 (IGF-1) levels had no significant effect on facial aging, which is inconsistent with previous findings in vitro. Conclusion: Regulating the levels of SHBG, BT, TT, and E2 may be an important means to delay facial aging.


Assuntos
Bancos de Espécimes Biológicos , Estudo de Associação Genômica Ampla , Hormônio do Crescimento , Testosterona , Hormônio do Crescimento/genética , Análise da Randomização Mendeliana , Testosterona/genética , Reino Unido/epidemiologia
9.
J Neuroeng Rehabil ; 20(1): 155, 2023 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-37957755

RESUMO

BACKGROUND: Sensory stimulation can play a fundamental role in the activation of the primary sensorimotor cortex (S1-M1), which can promote motor learning and M1 plasticity in stroke patients. However, studies have focused mainly on investigating the influence of brain lesion profiles on the activation patterns of S1-M1 during motor tasks instead of sensory tasks. Therefore, the objective of this study is to explore the lesion-specific activation patterns due to different brain lesion profiles and types during focal vibration (FV). METHODS: In total 52 subacute stroke patients were recruited in this clinical experiment, including patients with basal ganglia hemorrhage/ischemia, brainstem ischemia, other subcortical ischemia, cortical ischemia, and mixed cortical-subcortical ischemia. Electroencephalograms (EEG) were recorded following a resting state lasting for 4 min and three sessions of FV. FV was applied over the muscle belly of the affected limb's biceps for 3 min each session. Beta motor-related EEG power desynchronization overlying S1-M1 was used to indicate the activation of S1-M1, while the laterality coefficient (LC) of the activation of S1-M1 was used to assess the interhemispheric asymmetry of brain activation. RESULTS: (1) Regarding brain lesion profiles, FV could lead to the significant activation of bilateral S1-M1 in patients with basal ganglia ischemia and other subcortical ischemia. The activation of ipsilesional S1-M1 in patients with brainstem ischemia was higher than that in patients with cortical ischemia. No activation of S1-M1 was observed in patients with lesions involving cortical regions. (2) Regarding brain lesion types, FV could induce the activation of bilateral S1-M1 in patients with basal ganglia hemorrhage, which was significantly higher than that in patients with basal ganglia ischemia. Additionally, LC showed no significant correlation with the modified Barthel index (MBI) in all patients, but a positive correlation with MBI in patients with basal ganglia lesions. CONCLUSIONS: These results reveal that sensory stimulation can induce lesion-specific activation patterns of S1-M1. This indicates FV could be applied in a personalized manner based on the lesion-specific activation of S1-M1 in stroke patients with different lesion profiles and types. Our study may contribute to a better understanding of the underlying mechanisms of cortical reorganization.


Assuntos
Hemorragia dos Gânglios da Base , Acidente Vascular Cerebral , Humanos , Encéfalo , Eletroencefalografia , Isquemia , Imageamento por Ressonância Magnética
10.
J Am Chem Soc ; 145(46): 25214-25221, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37934914

RESUMO

We herein report the iridium-catalyzed enantioselective C-H borylation of aryl chlorides. A variety of prochiral biaryl compounds could be well-tolerated, affording a vast array of axially chiral biaryls with high enantioselectivities. The current method exhibits a high turnover number (TON) of 7000, which represents the highest in functional-group-directed asymmetric C-H activation. The high TON was attributed to a weak catalyst-substrate interaction that was caused by mismatched chirality between catalyst and substrate. We also demonstrated the synthetic application of the current method by C-B, ortho-C-H, and C-Cl bond functionalization, including programmed Suzuki-Miyaura coupling for the synthesis of axially chiral polyarenes.

11.
Clin Cosmet Investig Dermatol ; 16: 2737-2748, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37799505

RESUMO

Carvajal syndrome is a rare hereditary cardiocutaneous syndrome caused by the variants of the desmoplakin (DSP) gene. In this study, we report a patient of Carvajal syndrome with a novel homozygous missense variant of DSP gene. We diagnosed a 7-year-old female patient with Carvajal syndrome characterized by dilated cardiomyopathy, palmoplantar keratoderma, woolly hair, and dental dysplasia, who disclosed a novel homozygous missense variant c.4597C > T (p.Q1533X) in exon 6 of the DSP gene found for the first time. Both her parents were heterozygous for the identified nonsense variant c.4597C > T (p.Q1533X) in DSP gene but neither showed evidence of Carvajal syndrome, indicating that this novel variant causes the disease in an autosomal recessive manner. Genotypes of Carvajal syndrome are even broader than so far anticipated. When patients with dilated cardiomyopathy, palmoplantar keratoderma, woolly hair, and dental dysplasia are found in clinical practice, Carvajal syndrome should be highly suspected, and family gene sequencing should be actively carried out.

12.
Eur J Radiol ; 167: 111063, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37660486

RESUMO

OBJECTIVES: Whether stress CT myocardial perfusion imaging (CT-MPI) improves risk assessment in patients with diabetes mellitus (DM) remains unexplored. We aimed to evaluate the prognostic value of coronary CT angiography (CCTA) and stress CT-MPI in suspected coronary artery disease (CAD) patients with and without DM. METHODS: A total of 334 patients with suspected CAD who underwent CCTA and stress CT-MPI from May 2020 to July 2021 were retrospectively analyzed. The endpoint was major adverse cardiovascular events (MACEs). Multivariable Cox regression analysis was used to evaluate the risk factors for MACEs, including clinical risk factors, CCTA characteristics and CT-MPI characteristics. RESULTS: After a median follow-up of 21 months,15 patients of the DM group and 16 patients of the non-DM group experienced MACEs. Multivariate Cox stepwise regression analysis showed that abnormal perfusion myocardial segments ratio was associated with MACEs after adjusting for clinical risk factors and CCTA characteristics in all patients (HR:1.023, p < 0.001), DM group (HR:1.024, p = 0.008) and non-DM group (HR:1.028, p = 0.003). By adding CT-MPI characteristics to CCTA characteristics and clinical risk factors, the global chi-square for predicting MACEs increased from 62.24 to 78.84 in all patients (p < 0.001), from 19.18 to 27.30 in DM group (p = 0.004) and from 39.51 to 48.65 in non-DM group (p = 0.003); the increment of C-index in all patients, DM group and non-DM group were 0.018, 0.054 and 0.019, respectively. CONCLUSION: In all patients and those with and without DM, CT-MPI has incremental prognostic value over clinical risk factors alone or combined with CCTA characteristics in predicting MACEs.


Assuntos
Doença da Artéria Coronariana , Diabetes Mellitus , Imagem de Perfusão do Miocárdio , Humanos , Angiografia por Tomografia Computadorizada , Prognóstico , Estudos Retrospectivos , Angiografia Coronária , Tomografia Computadorizada por Raios X , Diabetes Mellitus/epidemiologia , Doença da Artéria Coronariana/diagnóstico por imagem
13.
Bioengineering (Basel) ; 10(9)2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37760199

RESUMO

Elderly people usually have poorer surgical tolerance and a higher incidence of complications when undergoing revision surgery after posterior instrumented lumbar fusion (PILF). Full-endoscopic transforaminal surgery is a safe and effective option, but sometimes, it is difficult to revise L5-S1 foraminal stenosis (FS) after PILF. Therefore, we developed full-endoscopic lumbar decompression (FELD) at the arthrodesis level via a modified interlaminar approach under local anesthesia. This study aimed to describe the technical note and clinical efficacy of the technique. Eleven patients with unilateral lower limb radiculopathy after PILF underwent selective nerve root block and then underwent FELD. Magnetic resonance imaging (MRI) and computer tomography (CT) were performed on the second postoperative day. Their clinical outcomes were evaluated with a Visual analog scale (VAS) of low back pain and sciatica pain, Oswestry disability index (ODI), and the MacNab score. Complete decompression was achieved in every case with FELD without serious complications. Postoperative VAS of sciatica pain and ODI at each time point and VAS of low back pain and ODI after three months postoperatively were significantly improved compared with those preoperative (p < 0.05). According to the MacNab criteria, seven patients (63.6%) had excellent results at the two-year follow-up, and four patients (36.4%) had good results. No patients required further revision surgery. FELD, via a modified interlaminar approach, is effective for treating unilateral L5-S1 FS after PILF in elderly people.

14.
Heliyon ; 9(7): e18251, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37539273

RESUMO

Objectives: Acute type A aortic dissection (ATAAD) with severe stenosis or occlusion of the true lumen of aortic arch branch vessels often leads to an increased incidence of severe postsurgical neurological complications and mortality rate. In this study, we aimed to introduce our institutional extra-anatomic revascularization and cannulation strategy with improved postoperative outcomes for better management of patients with cerebral malperfusion in the setting of ATAAD. Methods: Twenty-eight patients with ATAAD complicated by severe stenosis or occlusion of the aortic arch branch vessels, as noted on combined computed tomography angiography of the aorta and craniocervical artery, between January 2021 and June 2022 were included in this study. Basic patient characteristics, surgical procedures, hospitalization stays, and early follow-up results were analyzed. Results: The median follow-up duration was 16.5 months (interquartile range: 11.5-20.5), with a 100% completion rate. The 30-day mortality rates was 7.1% (2/28 patients); two patients had multiple cerebral infarctions on preoperative computed tomography and persistent coma. Postoperative transient neurological dysfunction occurred in 10.7% (3/28) of the patients, and no new permanent neurological dysfunction occurred. Of all the patients, 3.6% (1/28) had novel acute renal failure. No other deaths, secondary surgeries, or serious complications occurred during the early follow-up period. Conclusions: Use of extra-anatomic revascularization and a new cannulation strategy before cardiopulmonary bypass is safe and feasible and may reduce the high incidence of postoperative neurological complications in patients with ATAAD and cerebral malperfusion.

15.
Magn Reson Imaging ; 103: 216-223, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37517767

RESUMO

RATIONALE AND OBJECTIVES: To evaluate the performance of three-dimensional (3D) amide proton transfer-weighted (APTw) MRI in the differentiation between benign and malignant ovarian masses based on single-slice and all-slice analysis of cystic regions. MATERIALS AND METHODS: Patients were consecutively recruited and underwent conventional pelvic MRI and APTw MRI. Two radiologists independently assessed ovarian masses blinded to the histopathological results. Three APTw SI values were generated from the cystic regions of the masses: (1) APTw SI of a single representative slice (RS); (2) average (AVE) of APTw SIs of all slices of the mass; (3) area-weighted (AW) average of APTw SIs of all slices of the mass. O-RADS MRI score of each mass was reported. Independent sample t-test and receiver operating characteristic (ROC) curve analysis were performed for comparison. Inter- and intra-observer reliability were assessed by the intraclass correlation coefficient (ICC) and quadratic kappa coefficient. RESULTS: 46 ovarian masses were included for final analysis. The three APTw SI values were higher in cystic regions of malignant ovarian masses compared with benign lesions (p<0.0001). ROC curve analysis showed no significant difference in diagnostic performance among three APTw SI values and the O-RADS MRI score (AUC: RS-APTw SI, 0.930; AVE-APTw SI, 0.927; AW-APTw SI, 0.935; O-RADS score, 0.937). CONCLUSIONS: APTw MRI may be used as a noninvasive tool for the differentiation of benign and malignant ovarian masses based on the analysis of the cystic regions.


Assuntos
Neoplasias Ovarianas , Prótons , Humanos , Feminino , Amidas , Diagnóstico Diferencial , Reprodutibilidade dos Testes , Imageamento por Ressonância Magnética/métodos , Neoplasias Ovarianas/diagnóstico por imagem
16.
Nano Lett ; 23(16): 7508-7515, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37477210

RESUMO

Practical approaches to the synthesis of atomically precise metal nanoclusters are in high demand as they provide the structural basis for investigating nanomaterials' structure-property correlations with atomic precision. The Brust-Schiffrin method has been widely used, while the essential reductive ligands (e.g., thiols) limit the application of this method for synthesizing metal nanoclusters with specific frameworks and surface ligands. In this work, we developed a photochemical route for synthesizing atomically precise metal nanoclusters by applying disulfide, which is a widely available, stable, and environmentally friendly sulfur source. This method enables the construction of structurally diverse metal nanoclusters and especially features the synthesis of PhS-protected metal nanoclusters that were not easily achieved previously and the gram-scale synthesis. A reduction-oxidation cascade mechanism has been revealed for the photochemical route. This work is expected to open up new opportunities for metal nanocluster synthesis and will contribute to the practical applications of this kind of nanomaterial.

17.
Quant Imaging Med Surg ; 13(6): 3441-3450, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37284123

RESUMO

Background: This cross-sectional study sought to explore the possible risk factors assessed with magnetic resonance (MR) vessel wall imaging for hemodynamic instability (HI) during carotid artery stenting (CAS). Methods: Patients with carotid stenosis who were referred for CAS from January 2017 to December 2019 were recruited and underwent carotid MR vessel wall imaging. The vulnerable plaque features, including lipid-rich necrotic core (LRNC), intraplaque hemorrhage (IPH), fibrous cap rupture, and plaque morphology, were evaluated. The HI was defined as a drop of systolic blood pressure (SBP) of ≥30 mmHg or the lowest SBP measurement of <90 mmHg after stent implantation. The carotid plaque characteristics were compared between the HI and non-HI groups. The association between carotid plaque characteristics and HI was analyzed. Results: A total of 56 participants (mean age 68.7±8.3 years; 44 males) were recruited. Patients in the HI group (n=26, 46%) had a significantly greater wall area [median 43.2 (IQR, 34.9-50.5) vs. 35.9 (IQR, 32.3-39.4) mm2; P=0.008], total vessel area (79.7±17.2 vs. 69.9±17.3 mm2; P=0.03), prevalence of IPH (62% vs. 30%; P=0.02), prevalence of vulnerable plaque (77% vs. 43%; P=0.01), and volume of LRNC [median 344.7 (IQR, 155.1-665.7) vs. 103.1 (IQR, 53.9-162.9) mm3; P=0.001] in carotid plaque compared to those in non-HI group (n=30, 54%). Carotid LRNC volume (OR =1.005, 95% CI: 1.001-1.009; P=0.01) and presence of vulnerable plaque (OR =4.038, 95% CI: 0.955-17.070; P=0.06) were significantly and marginally associated with HI, respectively. Conclusions: Carotid plaque burden and vulnerable plaque features, particularly a larger LRNC, might be effective predictors for HI during the CAS procedure.

18.
Orthop Surg ; 15(7): 1893-1903, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37259903

RESUMO

OBJECTIVE: Obtaining sufficient decompression and solid fusion and avoiding approach-related injuries simultaneously are still challenging for the treatment of hard disc herniation in thoracolumbar junction. A combined full-endoscopic decompression and interbody fusion via a transforaminal approach was used to achieve this goal. The purpose of this study was to introduce the technical notes and clinical outcomes of this novel technique. METHODS: Twenty segments of hard disc herniations in the thoracolumbar junction of 14 patients treated with full-endoscopic interbody fusion via the transforaminal approach between January 2018 and September 2021 were analyzed. The patients were an average age of 43.3 years. Full-endoscopic interbody fusion and discectomy via the transforaminal approach were performed under local anesthesia, followed by percutaneous pedicle screw system fixation under general anesthesia. Imaging, including magnetic resonance imaging (MRI), computed tomography (CT), and X-ray, was carried out. MRI was performed on the second day and 3 months postoperatively. CT was performed on the second day, 6 months, and 1 year (as needed) postoperatively. Back and radicular pain, neurological function, and thoracic spine function were scored using a visual analog scale, the Nurick scale, and modified Japanese Orthopaedic Association (mJOA) scale, and the Oswestry disability index at 1 week, 3 months, 6 months, and 1 year postoperatively. RESULTS: All the operations were successfully completed, and no intraoperative conversion of the surgical methods occurred. Postoperative thoracolumbar junction MRI and CT examinations of all the patients revealed a sufficiently decompressed spinal cord or cauda equina, without any residual compression. At the 1-year follow-up, all the surgical segments were fused. Back and radicular pain was relieved in all the patients, and neurological function was restored. The average recovery rate of the mJOA was 72.5%, including seven excellent, five good, and two fair cases. Although dural tears occurred in two cases during the operation, no cerebrospinal fluid leakage or pseudomeningocele occurred during follow-up. No other surgical complications were noted. CONCLUSIONS: A combined full-endoscopic decompression and interbody fusion via a transforaminal approach can achieve complete spinal canal decompression and solid interbody fusion with fewer approach-related injuries. It is a safe and effective minimally invasive spine surgery for treating hard disc herniation in the thoracolumbar junction.


Assuntos
Deslocamento do Disco Intervertebral , Fusão Vertebral , Humanos , Adulto , Deslocamento do Disco Intervertebral/cirurgia , Descompressão Cirúrgica/métodos , Resultado do Tratamento , Vértebras Lombares/cirurgia , Fusão Vertebral/métodos , Dor , Estudos Retrospectivos
19.
Phys Med Biol ; 68(14)2023 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-37343591

RESUMO

Magneto-acousto-electrical tomography (MAET), which couples ultrasound imaging with electrical impedance tomography, is an electrical property imaging method which is expected to have a wide range of clinical applications, including the early detection of breast and liver cancers. Obviously, as a coupled imaging method, how to improve the signal-to-noise ratio (SNR) is a key issue in the imaging process. In this paper, a wavelet filtering method is introduced into MAET, which includes the filtering effect of the db6 wavelet, and its filtering effect at different decomposition levels. At the same time, based on the Lorentz reciprocity theorem, the wave equation satisfied by the detected voltage obtained by electrode was deduced. We also built an experimental platform to acquire signals by keeping the position of the target unchanged and moving the ultrasound transducer along the trajectory of a circular arc. The experimental results show that the wavelet filtering scheme proposed in this paper improves the SNR of the detected signal of 15.1 dB, and the images of electrical properties of the phantom and pork from isolated tissues were realized by the filtered signal of the db6 wavelet and time reversal method, which reflects the interface of electrical conductivity change of tissues. This scanning method, of fixing the target body and rotating the transducer, can effectively reduce the error and noise caused by the movement of the detection electrodes in the experiment. The filtering technique and imaging algorithm proposed in this paper have improved the SNR and contrast of the images. Thus, the images of the low conductivity phantom with 0.2 S m-1and isolated tissue were obtained, which indicates that the MAET has good prospects in clinical applications.


Assuntos
Acústica , Tomografia , Tomografia/métodos , Tomografia Computadorizada por Raios X/métodos , Eletricidade , Condutividade Elétrica , Imagens de Fantasmas , Algoritmos
20.
Gels ; 9(5)2023 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-37233019

RESUMO

Stimuli-responsive actuating hydrogels response to the external stimulus with complex deformation behaviors based on the programmable anisotropic structure design are one of the most important smart soft materials, which have great potential applications in artificial muscles, smart values, and mini-robots. However, the anisotropic structure of one actuating hydrogel can only be programmed one time, which can only provide single actuating performance, and subsequently, has severely limited their further applications. Herein, we have explored a novel SMP/hydrogel hybrid actuator through combining polyurethane shape memory polymer (PU SMP) layer and pH-responsive polyacrylic-acid (PAA) hydrogel layer by a napkin with UV-adhesive. Owing to both the super-hydrophilicity and super-lipophilicity of the cellulose-fiber based napkin, the SMP and the hydrogel can be bonded firmly by the UV-adhesive in the napkin. More importantly, this bilayer hybrid 2D sheet can be programmed by designing a different temporary shape in heat water which can be fixed easily in cool water to achieve various fixed shapes. This hybrid with a fixed temporary shape can achieve complex actuating performance based on the bi-functional synergy of temperature-triggered SMP and pH-responsive hydrogel. The relatively high modulus PU SMP achieved high to 87.19% and 88.92% shape-fixing ratio, respectively, correspond to bending and folding shapes. The hybrid actuator can actuate with the 25.71 °/min actuating speed. Most importantly, one SMP/hydrogel bi-layer hybrid sheet was repeatedly programmed at least nine times in our research to fix various temporary 1D, 2D and 3D shapes, including bending, folding and spiraling shapes. As a result, only one SMP/hydrogel hybrid can provide various complex stimuli-responsive actuations, including the reversable bending-straightening, spiraling-unspiraling. A few of the intelligent devices have been designed to simulate the movement of the natural organisms, such as bio-mimetic "paw", "pangolin" and "octopus". This work has developed a new SMP/hydrogel hybrid with excellent multi-repeatable (≥9 times) programmability for high-level complex actuations, including the 1D to 2D bending and the 2D to 3D spiraling actuations, which also provides a new strategy to design other new soft intelligent materials and systems.

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