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1.
J Org Chem ; 89(9): 6607-6614, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38624206

RESUMO

The trivalent phosphine-catalyzed [4+1] spiro-annulation reaction of allenyl imide and activated methylene cyclocompounds has been developed for the construction of various spiro-2-cyclopenten-1-ones. Oxindoles, 3-isochromanones, and 2-indanones are selected as 1C synthons to capture the in situ-generated bis-electrophilic α,ß-unsaturated ketenyl phosphonium intermediate, affording the corresponding monospiro- and bispiro-cyclopentenones in good to excellent yields (≤91%) under mild conditions. The primary attempt at asymmetric catalysis using monophosphine (R)-SITCP provides promising enantioselectivity (45% ee). A plausible reaction mechanism is also proposed.

2.
Methods ; 208: 42-47, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36341922

RESUMO

The adaptor proteins play a crucially important role in regulating lymphocyte activation. Rapid and efficient identification of adaptor proteins is essential for understanding their functions. However, biochemical methods require not only expensive experimental costs, but also long experiment cycles and more personnel. Therefore, a computational method that could accurately identify adaptor proteins is urgently needed. To solve this issue, we developed a classifier that combined the support vector machine (SVM) with the composition of k-Spaced Amino Acid Pairs (CKSAAP) and the amino acid composition (AAC) to identify adaptor proteins. Analysis of variance (ANOVA) was used to select the optimized features which could generate the maximum prediction performance. By examining the proposed model on independent data, we found that the 447 optimized features could achieve an accuracy of 92.39% with an AUC of 0.9766, demonstrating the powerful capabilities of our model. We hope that the proposed model could provide more clues for studying adaptor proteins.


Assuntos
Biologia Computacional , Máquina de Vetores de Suporte , Biologia Computacional/métodos , Aminoácidos/metabolismo , Análise de Variância
3.
Appl Opt ; 62(31): 8348-8356, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-38037939

RESUMO

Aiming at the difficulty of detecting the modulation transfer function (MTF) of Bayer color cameras during focusing, the traditional scheme is modified in this paper. First, through analysis, it is found that the MTF of the Bayer detector decreased substantially compared to the monochromatic detector, which was caused by the loss of a large amount of light from the Bayer detector. When the MTF is calculated for the color image after de-mosaicing, the degradation of image quality leads to the inability to obtain the full-frequency MTF curve. Therefore, this paper proposes a solution to detect the MTFs of the three primary colors in the Bayer image individually, and then weight the MTFs of each primary color to obtain the MTF of the color image based on the calibration results of the light source. Then, considering the steps of differentiation and Fourier transform in the slanted-edge method, this paper solves the problem of non-uniform sampling of edge spread function by using the modification of the slanted-edge method with non-uniform Fourier transform. Finally, the optimal imaging position of a certain type of Bayer color camera is determined using the methods proposed in this paper. Simulation and test results verify the effectiveness and accuracy of the methods in this paper.

4.
BMC Geriatr ; 23(1): 269, 2023 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-37142974

RESUMO

BACKGROUND: Perforated peptic ulcer (PPU) remains challenging surgically due to its high mortality, especially in older individuals. Computed tomography (CT)-measured skeletal muscle mass is a effective predictor of the surgical outcomes in older patients with abdominal emergencies. The purpose of this study is to assess whether a low CT-measured skeletal muscle mass can provide extra value in predicting PPU mortality. METHODS: This retrospective study enrolled older (aged ≥ 65 years) patients who underwent PPU surgery. Cross-sectional skeletal muscle areas and densities were measured by CT at L3 and patient-height adjusted to obtain the L3 skeletal muscle gauge (SMG). Thirty-day mortality was determined with univariate, multivariate and Kaplan-Meier analysis. RESULTS: From 2011 to 2016, 141 older patients were included; 54.8% had sarcopenia. They were further categorized into the PULP score ≤ 7 (n=64) or PULP score > 7 group (n=82). In the former, there was no significant difference in 30-day mortality between sarcopenic (2.9%) and nonsarcopenic patients (0%; p=1.000). However, in the PULP score > 7 group, sarcopenic patients had a significantly higher 30-day mortality (25.5% vs. 3.2%, p=0.009) and serious complication rate (37.3% vs. 12.9%, p=0.017) than nonsarcopenic patients. Multivariate analysis showed that sarcopenia was an independent risk factor for 30-day mortality in patients in the PULP score > 7 group (OR: 11.05, CI: 1.03-118.7). CONCLUSION: CT scans can diagnose PPU and provide physiological measurements. Sarcopenia, defined as a low CT-measured SMG, provides extra value in predicting mortality in older PPU patients.


Assuntos
Úlcera Péptica Perfurada , Sarcopenia , Humanos , Idoso , Estudos Retrospectivos , Sarcopenia/diagnóstico por imagem , Sarcopenia/complicações , Estudos Transversais , Úlcera Péptica Perfurada/diagnóstico por imagem , Úlcera Péptica Perfurada/cirurgia , Fatores de Risco
5.
Sensors (Basel) ; 23(9)2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37177649

RESUMO

Bayer filter color cameras are more and more widely used in the field of aerospace remote sensing, but the Bayer filter causes great degradation in image quality; therefore, obtaining a means of achieving the high-precision measurement of the modulation transfer function (MTF) of Bayer filter color cameras is an urgent problem. In order to solve this problem, this paper develops a slanted-edge method via three steps: the detection of the slanted edge, the acquisition and processing of the edge spread function (ESF), and the acquisition and processing of the line spread function (LSF). A combination of the Canny operator and Hough transform is proposed for the detection of the slanted edge, which improves the fitting accuracy and anti-interference ability of the algorithm. Further, the Canny operator is improved by constructing an adaptive filter function and introducing the Otsu method, which can more effectively smooth the image and remove its false edges. A method of processing ESF data by combining cubic spline interpolation and Savitzky-Golay (SG) filtering is proposed, which reduces the effects of noise and the non-uniform sampling of ESF on MTF. A method of LSF processing using Gaussian function fitting is proposed to further reduce the effect of noise on MTF. The improved algorithm is verified by the MTF measurement test applied to a specific type of Bayer filter color space camera. The simulation and test results show that the improved slanted-edge method discussed in this paper has greater precision and a better anti-interference ability, and it can effectively solve the difficult problem associated with MTF detection in Bayer filter color space cameras.

6.
Zhonghua Nan Ke Xue ; 28(7): 618-621, 2022 Jul.
Artigo em Zh | MEDLINE | ID: mdl-37556220

RESUMO

OBJECTIVE: To report a case of complete androgen insensitivity syndrome with a special family history and its genetic analysis. METHODS: We studied the medical history, diagnosis and treatment of a case of complete androgen insensitivity syndrome, collected blood samples from the patient and his mother for whole exome sequencing, and analyzed the genetic etiology. RESULTS: The patient presented with "primary amenorrhea" and diagnosed with male pseudohermaphroditism, with the karyotype as 46, XY. Surgery confirmed undescended testes in the abdominal cavity. The androgen level was higher than normal. Whole exome sequencing of the patient and his mother found c.2678C>T (p.P893L) but no other abnormalities, which was considered as a suspected pathogenic mutation of complete androgen insensitivity syndrome. The patient had a "sister" with a similar medical history. CONCLUSION: c.2678C>T (p.P893L) is a suspected pathogenic mutation of complete androgen insensitivity syndrome, which usually cannot be detected until puberty, making it easy to delay the diagnosis.


Assuntos
Síndrome de Resistência a Andrógenos , Criptorquidismo , Feminino , Humanos , Masculino , Síndrome de Resistência a Andrógenos/genética , Síndrome de Resistência a Andrógenos/diagnóstico , Mutação , Cariotipagem , Cariótipo , Receptores Androgênicos/genética
7.
Opt Express ; 29(4): 5552-5566, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33726090

RESUMO

Single photon counting compressive imaging, a combination of single-pixel-imaging and single-photon-counting technology, is provided with low cost and ultra-high sensitivity. However, it requires a long imaging time when applying traditional compressed sensing (CS) reconstruction algorithms. A deep-learning-based compressed reconstruction network refrains iterative computation while achieving efficient reconstruction. This paper proposes a compressed reconstruction network (OGTM) based on a generative model, adding sampling sub-network to achieve joint-optimization of sampling and generation for better reconstruction. To avoid the slow convergence caused by alternating training, initial weights of the sampling and generation sub-network are transferred from an autoencoder. The results indicate that the convergence speed and imaging quality are significantly improved. The OGTM validated on a single-photon compressive imaging system performs imaging experiments on specific and generalized targets. For specific targets, the results demonstrate that OGTM can quickly generate images from few measurements, and its reconstruction is better than the existing compressed sensing recovery algorithms, compensating defects of the generative models in compressed sensing.

8.
Zhonghua Nan Ke Xue ; 27(1): 39-44, 2021 Jan.
Artigo em Zh | MEDLINE | ID: mdl-34914279

RESUMO

OBJECTIVE: To investigate the impacts of surgical treatment of penile fracture on the short- and long-term psychological, erectile and urinary functions of the patient. METHODS: Fifty patients with penile fracture underwent surgical treatment in the Emergency Department of our hospital from June 2010 to December 2015. Using the Self-Rating Depression Scale (SDS), Self-Rating Anxiety Scale (SAS), IIEF-5 and IPSS, we evaluated the psychological, erectile and urinary functions of the patients at 1 day, 6 months and 18 months after surgery, and analyzed the relationship between psychological and erectile functions as well as the possible factors affecting erectile function postoperatively. RESULTS: Compared with the baseline, significant increases were observed at 6 months after surgery in the SDS score (30.3 ± 4.1 vs 50.7 ± 6.5, P < 0.01) and SAS score (29.9 ± 5.9 vs 55.4 ± 7.7, P < 0.01) but a remarkable decrease in the IIEF-5 score (22.4 ± 1.3 vs 18.4 ± 2.1, P < 0.01). At 18 months, neither SDS (50.7 ± 10.0) or SAS score (54.1 ± 8.7) showed any statistically significant difference from that at 6 months (P > 0.05), but the IIEF-5 score (21.1 ± 2.2) was markedly lower than the baseline (P < 0.01), though higher than that at 6 months (P < 0.01). The IPSS scores at 6 and 18 months exhibited were not significantly different from that preoperatively (P > 0.05). Both the SDS and SAS scores were evidently higher in the patients with severe than in those with mild ED. The body mass index (BMI) and waiting time for surgery were significantly negatively correlated with short- and long-term erectile function of the patients after surgery. CONCLUSIONS: Patients with penile fracture may have decreased erectile function after surgery, accompanied with anxiety and depression. The risk factors for ED include BMI and waiting-for-surgery time.


Assuntos
Ereção Peniana , Índice de Massa Corporal , Humanos , Masculino
9.
Angew Chem Int Ed Engl ; 59(5): 1884-1890, 2020 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-31747102

RESUMO

Unprecedented phosphine-catalyzed [4+1] cycloadditions of allenyl imides have been discovered using various N-based substrates including methyl ketimines, enamines, and a primary amine. These transformations provide a one-pot access to cyclopentenoyl enamines and imines, or (chiral) γ-lactams through two geminal C-C bond or two C-N bond formations, respectively. Several P-based key intermediates including a 1,4-(bis)electrophilic α,ß-unsaturated ketenyl phosphonium species have been detected by 31 P NMR and HRMS analyses, which shed light on the postulated catalytic cycle. The synthetic utility of this new chemistry has been demonstrated through a gram-scaling up of the catalytic reaction as well as regioselective hydrogenation and double condensation to form cyclopentanoyl enamines and fused pyrazole building blocks, respectively.

10.
Opt Express ; 26(15): 19080-19090, 2018 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-30114168

RESUMO

We demonstrate a single photon compressive imaging system with the image plane up to the entire digital micro-mirror device (DMD) work area. A parallel light source is designed to reduce the influence of light scattering on imaging resolution and a photon counting photomultiplier tube (PMT) with a large photosensitive area is used to effectively collect light reflected from the full screen of DMD. A control and counting circuit, based on Field-Programmable Gate Array (FPGA), is developed to load binary random matrix into the DMD controller for each measurement, and to count single-photon pulse output from PMT simultaneously. To reduce imaging time and huge memory occupation for image reconstruction, a multiple micro-mirrors combination imaging method is proposed. The signal-to-noise ratio and detection limit of the imaging system is theoretically deduced. Theoretical analysis and experimental results show that micro-mirrors combination imaging method is more suitable for faster imaging in a weaker-light-level environment. In order to achieve high imaging quality, the size of the combined pixels and the average time of each measurement should be moderate, so that the impact of Poisson shot noise is minimized.

11.
J Org Chem ; 83(11): 6133-6141, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29732894

RESUMO

A transition-metal-free approach for the preparation of N-arylketimines has been developed from the direct reaction of aryldiazonium salts, arenes, and nitriles in a one-pot fashion with the consecutive formation of N-C and C-C bonds. This approach proceeds via an in situ generation of N-arylnitrilium intermediate, which then undergoes intermolecular arylation. This three-component strategy offers a step- and atom-efficient way to N-arylketimines from easily accessible reagents under mild reaction conditions. The characterization of stereochemistry of ketimine was achieved by X-ray crystallographic structure and theoretical calculation. Operational simplicity, shorter reaction time, excellent functional group compatibility, and scalability are the key features of this report.

12.
Acta Pharmacol Sin ; 38(3): 362-370, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28042873

RESUMO

Cardiovascular complications represent a leading cause of mortality in patients with type 2 diabetes mellitus (T2DM). During such complicated progression, subtle variations in the cardiovascular risk (CVR)-related biomarkers have been used to identify cardiovascular disease at the incipient stage. In this study we attempt to integrally characterize the progression of cardiovascular complications and to assess the beneficial effects of metformin combined with salvianolic acid A (Sal A), in Goto-Kakizaki (GK) rats with spontaneous T2DM. The rats were treated with metformin (200 mg·kg-1·d-1, ig) alone or in combination with Sal A (1 mg·kg-1·d-1, ip) at ages from 8 to 22 weeks. During the treatment, the levels of asymmetric dimethylarginine, L-arginine, superoxide dismutase, malondialdehyde, glucose, high density lipoprotein and low density lipoprotein were assessed. Based on alterations in these biomarkers, a mini-network balance model was established using matrixes and vectors. Radar charts were created to visually depict the disruption of CVR-related modules (endothelial function, oxidative stress, glycation and lipid profiles). The description for the progression of cardiovascular disorder was quantitatively represented by u, the dynamic parameter of the model. The modeling results suggested that untreated GK rats tended to have more severe cardiovascular complications than the treatment groups. Metformin monotherapy retarded disease deterioration, whereas the combination treatment ameliorated the disease progression via restoring the balance. The current study, which focused on the balance of the mini-network and interactions among CVR-related modules, proposes a novel method for evaluating the progression of cardiovascular complications in T2DM as well as a more beneficial intervention strategy.


Assuntos
Doenças Cardiovasculares/fisiopatologia , Complicações do Diabetes/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Modelos Biológicos , Alcenos/uso terapêutico , Animais , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , Complicações do Diabetes/prevenção & controle , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Progressão da Doença , Quimioterapia Combinada , Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Polifenóis/uso terapêutico , Ratos Wistar
13.
Med Sci Monit ; 21: 3955-690, 2015 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-26683656

RESUMO

BACKGROUND Prostate cancer is a one of the most common malignant diseases in men worldwide. Now it is a challenge to identify patients at higher risk for relapse and progression after surgery, and more novel prognostic biomarkers are needed. The aim of this study was to investigate the clinical significance of protocadherin17 (PCDH17) methylation in serum and its predictive value for biochemical recurrence (BCR) after radical prostatectomy. MATERIAL AND METHODS We evaluated the methylation status of PCDH17 in serum samples of 167 early-stage prostate cancer patients and 44 patients with benign prostatic hyperplasia (BPH) using methylation-specific PCR (MSP), and then evaluated the relationship between PCDH17 methylation and clinicopathologic features. Kaplan-Meier survival analysis and Cox analysis were used to evaluate its predictive value for BCR. RESULTS The ratio of PCDH17 methylation in prostate cancer patients was higher than in patients with BPH. Moreover, PCDH17 methylation was significantly associated with advanced pathological stage, higher Gleason score, higher preoperative PSA levels, and BCR. Kaplan-Meier survival analysis indicated that patients with methylated PCDH17 had shorter BCR-free survival time compared to patients with unmethylated PCDH17. Cox regression analysis indicated that PCDH17 methylation was an independent predictive factor for the BCR of patients after radical prostatectomy. CONCLUSIONS PCDH17 methylation in serum is a frequent event in early-stage prostate cancer, and it is an independent predictor of BCR after radical prostatectomy.


Assuntos
Biomarcadores Tumorais/sangue , Caderinas/sangue , Recidiva Local de Neoplasia , Prostatectomia , Neoplasias da Próstata/patologia , Idoso , Humanos , Masculino , Metilação , Neoplasias da Próstata/sangue , Neoplasias da Próstata/cirurgia
14.
Yi Chuan ; 37(12): 1175-84, 2015 12.
Artigo em Zh | MEDLINE | ID: mdl-26704942

RESUMO

Adipose tissues play a critical role in the regulation of energy metabolism and homeostasis, and is also an important endocrine organ. Adipocyte differentiation is a complicated physiological process during which mesenchymal stem cells differentiate into adipocytes. This process is synergistically regulated by a large number of transcription factors, hormones and signaling pathway molecules. As a class of endogenous non-coding RNA (ncRNA), microRNAs (miRNAs) regulate gene expression mainly through post-transcriptional translational repression. In recent years, numerous studies have demonstrated that miRNA could have an impact on adipocyte differentiation and adipogenesis by modulating the expression levels of several adipogenic transcription factors and key signaling molecules. In this review, we summarize the mechanism of miRNA in regulating the differentiation of white/brown/beige adipocytes and the relevant signaling pathways and key factors, in the hope of providing theoretical guidance and new thoughts for treating obesity and other metabolic diseases.


Assuntos
Adipócitos/metabolismo , Adipogenia , Regulação da Expressão Gênica , MicroRNAs/metabolismo , Adipócitos/citologia , Animais , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/síntese química , MicroRNAs/genética , Transdução de Sinais
15.
Sci Adv ; 10(13): eadl4842, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38552028

RESUMO

The high-capacity advantage of lithium metal anode was compromised by common use of copper as the collector. Furthermore, lithium pulverization associated with "dead" Li accumulation and electrode cracking deteriorates the long-term cyclability of lithium metal batteries, especially under realistic test conditions. Here, we report an ultralight, integrated anode of polyimide-Ag/Li with dual anti-pulverization functionality. The silver layer was initially chemically bonded to the polyimide surface and then spontaneously diffused in Li solid solution and self-evolved into a fully lithiophilic Li-Ag phase, mitigating dendrites growth or dead Li. Further, the strong van der Waals interaction between the bottommost Li-Ag and polyimide affords electrode structural integrity and electrical continuity, thus circumventing electrode pulverization. Compared to the cutting-edge anode-free cells, the batteries pairing LiNi0.8Mn0.1Co0.1O2 with polyimide-Ag/Li afford a nearly 10% increase in specific energy, with safer characteristics and better cycling stability under realistic conditions of 1× excess Li and high areal-loading cathode (4 milliampere hour per square centimeter).

16.
Zhongguo Gu Shang ; 36(12): 1191-5, 2023 Dec 25.
Artigo em Zh | MEDLINE | ID: mdl-38130231

RESUMO

OBJECTIVE: To explore clinical effect of attaching locking plate with bone grafting based on retaining the original intramedullary nail in treating non-union after intramedullary nail fixation of long shaft fractures of lower limbs. METHODS: A retrospective study was conducted on 20 patients treated with non-union fractures after intramedullary nailing of long shaft fractures of lower limbs from June 2015 to June 2020. All patients were treated with the original intramedullary nailing and bone grafting from the iliac bone, and were underwent open reduction plate internal fixation and bone grafting for old fractures. Among them, 14 were males and 6 were females, aged from 35 to 56 years old with an average of (42.2±9.6) years old. Nine patients were femoral shaft fracture and 11 patients were tibial shaft fracture. According to characteristics of fracture end nonunion, 6 patients were stable/atrophic, 9 patients were unstable/large, and 5 patients were unstable/atrophic. The nonunion time ranged from 8 to 12 months with an average of(9.8±2.0) months after the initial surgery. Visual analogue scale (VAS), knee range of motion, bone healing time, complications and fracture-end healing were recorded before and at the latest follow-up. RESULTS: All patients were followed up for 18 to 48 months with an average of (36.3±10.5) months. The incision of all patients were healed at stageⅠwithout complications such as infection or internal fixation ruptur. Healing time of femur and tibia was (8.5±2.6) months and (9.5±2.2) months. Knee joint motion increased from preoperative (101.05±8.98) ° to postoperative (139.35±8.78) ° at the latest follow-up (t=-12.845, P<0.001). VAS decreased from preoperative (5.15±1.72) to postoperative (0.75±0.96) at the latest follow-up (t=11.186, P<0.001). CONCLUSION: On the basis of retaining the original intramedullary nail, the addition of locking plate internal fixation and autogenous iliac bone grafting have advantages of simple operation, less trauma, fewer complications and high fracture healing rate. It is one of the effective surgical schemes for the treatment of nonunion after intramedullary nail fixation of long bone fracture of lower extremity.


Assuntos
Fraturas do Fêmur , Fixação Intramedular de Fraturas , Fraturas não Consolidadas , Fraturas da Tíbia , Masculino , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Transplante Ósseo , Estudos Retrospectivos , Placas Ósseas , Fixação Intramedular de Fraturas/efeitos adversos , Fraturas do Fêmur/cirurgia , Fraturas do Fêmur/complicações , Extremidade Inferior , Fraturas não Consolidadas/cirurgia , Consolidação da Fratura , Fraturas da Tíbia/complicações , Pinos Ortopédicos , Resultado do Tratamento
17.
Front Med (Lausanne) ; 10: 1052923, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36778738

RESUMO

Introduction: Bitter peptides are short peptides with potential medical applications. The huge potential behind its bitter taste remains to be tapped. To better explore the value of bitter peptides in practice, we need a more effective classification method for identifying bitter peptides. Methods: In this study, we developed a Random forest (RF)-based model, called Bitter-RF, using sequence information of the bitter peptide. Bitter-RF covers more comprehensive and extensive information by integrating 10 features extracted from the bitter peptides and achieves better results than the latest generation model on independent validation set. Results: The proposed model can improve the accurate classification of bitter peptides (AUROC = 0.98 on independent set test) and enrich the practical application of RF method in protein classification tasks which has not been used to build a prediction model for bitter peptides. Discussion: We hope the Bitter-RF could provide more conveniences to scholars for bitter peptide research.

18.
RSC Adv ; 13(35): 24628-24638, 2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37601589

RESUMO

Acetylene hydrogenation is a well-accepted solution to reduce by-products in the ethylene production process, while one of the key technical difficulties lies in developing a catalyst that can provide highly dispersed active sites. In this work, a highly crystalline layered covalent organic framework (COF) material (TbBpy) with excellent thermal stability was synthesized and firstly applied as support for ultrasmall Pd nanoparticles to catalyze acetylene hydrogenation. 100% of C2H2 conversion and 88.2% of C2H4 selectivity can be obtained at 120 °C with the space velocity of 70 000 h-1. The reaction mechanism was elucidated by applying a series of characterization techniques and theoretical calculation. The results indicate that the coordination between Pd and N atom in the bipyridine functional groups of COFs successfully increased the dispersibility and stability of Pd particles, and the introduction of COFs not only improved the adsorption of acetylene and H2 onto catalyst surface, but enhanced the electron transfer process, which can be responsible for the high selectivity and activity of catalyst. This work, for the first time, reported the excellent performance of Pd@TbBpy as a catalyst for acetylene hydrogenation and will facilitate the development and application of COFs materials in the area of petrochemicals.

19.
Asian J Androl ; 25(2): 217-222, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36722578

RESUMO

The Prostate Imaging Reporting and Data System (PI-RADS) has good ability to identify the nature of lesions on prostate magnetic resonance imaging (MRI). However, some lesions are still reported as PI-RADS 4 and 5 but are biopsy-proven benign. Herein, we aimed to summarize the reasons for the negative prostate biopsy of patients who were assessed as PI-RADS 4 and 5 by biparameter MRI. We retrospectively sorted out the prostate MRI, treatment, and follow-up results of patients who underwent a biparameter MRI examination of the prostate in The First Affiliated Hospital of Nanjing Medical University (Nanjing, China) from August 2019 to June 2021 with PI-RADS 4 and 5 but a negative biopsy. We focused on reviewing the MRI characteristics. A total of 467 patients underwent transperineal prostate biopsy. Among them, biopsy pathology of 93 cases were negative. After follow-up, 90 patients were ruled out of prostate cancer. Among the 90 cases, 40 were considered to be overestimated PI-RADS after review. A total of 22 cases were transition zone (TZ) lesions with regular appearance and clear boundaries, and 3 cases were symmetrical lesions. Among 15 cases, the TZ nodules penetrated the peripheral zone (PZ) and were mistaken for the origin of PZ. A total of 17 cases of lesions were difficult to distinguish from prostate cancer. Among them, 5 cases were granulomatous inflammation (1 case of prostate tuberculosis). A total of 33 cases were ambiguous lesions, whose performance was between PI-RADS 3 and 4. In summary, the reasons for "false-positive MRI diagnosis" included PI-RADS overestimation, ambiguous images giving higher PI-RADS, diseases that were really difficult to distinguish, and missed lesion in the initial biopsy; and the first two accounted for the most.


Assuntos
Neoplasias da Próstata , Masculino , Humanos , Neoplasias da Próstata/patologia , Imageamento por Ressonância Magnética/métodos , Estudos Retrospectivos , Biópsia Guiada por Imagem/métodos , Próstata/patologia
20.
Eur J Pharmacol ; 943: 175554, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36709792

RESUMO

High-fat diet (HFD)-induced obesity leads endothelial dysfunction and contributes to cardiovascular diseases. Palmitic acid (PA), a free fatty acid, is the main component of dietary saturated fat. Physcion, a chemical ingredient from Rhubarb, has been shown anti-hypertensive, anti-bacteria, and anti-tumor properties. However, the effects of physcion on endothelial dysfunction under HFD-induced obesity have not been reported. The purpose of the present study was to define the protective effect of physcion on HFD-induced endothelial dysfunction and its mechanisms involved. Obesity rat model was induced by HFD for 12 weeks. A rat thoracic aortic ring model was used to investigate the effects of physcion on HFD-induced impairment of vasorelaxation. Endothelial cell injury model was constructed in human umbilical vein endothelial cells (HUVECs) by treating with PA (0.25 mM) for 24 h. The results revealed that physcion reduced body weight and the levels of plasma TG, prevented impairment of endothelium-dependent relaxation in HFD-fed rats. In PA-injured HUVECs, physcion inhibited impaired viability, apoptosis and inflammation. Physcion also suppressed PA-induced both oxidative stress and ER stress in HUVECs. Furthermore, physcion increased PA-induced decrease in the activation of eNOS/Nrf2 signaling in HUVECs. These findings suggest that physcion has a significant beneficial effect on regulating HFD-induced endothelial dysfunction, which may be related to the inhibition of oxidative stress and ER stress through activation of eNOS/Nrf2 signaling pathway.


Assuntos
Dieta Hiperlipídica , Fator 2 Relacionado a NF-E2 , Animais , Humanos , Ratos , Estresse do Retículo Endoplasmático , Endotélio Vascular , Células Endoteliais da Veia Umbilical Humana , Fator 2 Relacionado a NF-E2/metabolismo , Obesidade/etiologia , Obesidade/prevenção & controle , Obesidade/metabolismo , Estresse Oxidativo
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