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1.
Org Lett ; 26(11): 2287-2291, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38456813

RESUMEN

A simple and efficient Rh2(OAc)4/DPPM (bis(diphenylphosphanyl)methane) catalyzed regioselective 1,2-anti-Markovnikov hydrosilylation of conjugated dienes with various tertiary silanes gave homoallylic silanes in acetonitrile, which tolerate broad functional groups. Control experiments proved that no π-allyl transition metal intermediates were involved in this 1,2-anti-Markovnikov hydrosilylation. Dirhodium hydride species was observed in hydrosilylation, suggesting that a direct insertion of the terminal double bond into a Rh-H bond is involved in this reaction.

2.
Org Biomol Chem ; 21(14): 2955-2959, 2023 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-36935630

RESUMEN

A simple, mild and efficient sequential KOtBu/FeCl3-catalyzed reductive phosphonylation of tertiary amides is herein described. This process first involved the KOtBu-catalyzed selective semi-reduction of tertiary amides to hemiaminal intermediates by TMDS (1,1,3,3-tetramethyldisiloxane) and then the FeCl3-catalyzed nucleophilic addition of the hemiaminal intermediates to phosphonates, which allowed the straightforward synthesis of α-amino phosphonates in moderate to good yields. This method applied well to amides and lactams that bear no strong acidic α-hydrogens, and various functional groups, including methoxy, methylthio, cyano, halogen, and heterocycles, could be tolerated.

3.
Front Cardiovasc Med ; 10: 1120665, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38500679

RESUMEN

Objective: To investigate the effects of different rehabilitation modalities on cardiopulmonary function in patients with acute coronary syndrome after revascularization. Methods: Two randomized controlled trials were conducted. All patients were stable for more than 48 h and less than 1 week after revascularization for acute coronary syndrome and were randomly assigned to Group A (home-based rehabilitation group) or Group B (center guided home-based rehabilitation group). The cardiopulmonary exercise test was mainly performed before and 3 months after cardiac rehabilitation (at the end of intervention). The primary endpoints of the study were peak oxygen uptake (VO2peak), and the secondary endpoints were maximum metabolic equivalents (METs), anaerobic threshold exercise load (Load AT), maximal workload (Load max), and anaerobic threshold oxygen uptake (VO2 AT). Results: A total of 106 patients were included in the study, with 47 patients in Group A (with 6 losses) and 50 patients in Group B (with 3 losses). There were no significant difference between the two groups in terms of age, gender, body mass index (BMI), left ventricular ejection fraction(LVEF), low-density lipoprotein cholesterol(LDL-C),cardiovascular risk factors. In Group A, no significant differences in CPET indices were observed before and after the intervention. In Group B, values of maximum metabolic equivalents (METs), peak heart rate (PHR), anaerobic threshold exercise load (Load AT), maximal workload (Load max), maximum ventilation per minute (VE max), peak oxygen uptake (VO2peak), anaerobic threshold oxygen uptake (VO2 AT) and maximum oxygen pulse (VO2/HRmax) were higher than those before the intervention (P < 0.05). In addition, METs (max), Load AT, Load max, VO2 AT, and VO2peak in Group B were higher than those in group A (P < 0.05). The change rates of VO2peak, METs(max), PHR, Load max, VO2 AT, VE max, VO2/HR(max) in the two groups were significantly different before and after intervention (P < 0.05). Conclusion: Cardiac exercise rehabilitation is helpful for improving patients' cardiopulmonary endurance and quality of life. Moreover, rehabilitation modalities with regular hospital guidance can improve cardiopulmonary function in a shorter period,which seems to be more effective than a complete home-based rehabilitation model. Clinical Trial Registration: http://www.chictr.org.cn, identifier (ChiCTR2400081034).

4.
Org Lett ; 24(41): 7512-7516, 2022 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-36214421

RESUMEN

Asymmetric hydrogenation of diaryl 1,4-diketones was achieved by using trans-RuCl2[(S)-BINAP)][(S)-Daipen] as the catalyst and the reaction gave rise to excellent enantio- and diastereoselectivities (up to >99% ee and de). This procedure provides a convenient and efficient synthetic method for chiral 1,4-diarylbutane-1,4-diols, which are important intermediates for a variety of chiral auxiliaries and ligands.

5.
Front Plant Sci ; 13: 868745, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35651761

RESUMEN

As one of the representative algorithms of deep learning, a convolutional neural network (CNN) with the advantage of local perception and parameter sharing has been rapidly developed. CNN-based detection technology has been widely used in computer vision, natural language processing, and other fields. Fresh fruit production is an important socioeconomic activity, where CNN-based deep learning detection technology has been successfully applied to its important links. To the best of our knowledge, this review is the first on the whole production process of fresh fruit. We first introduced the network architecture and implementation principle of CNN and described the training process of a CNN-based deep learning model in detail. A large number of articles were investigated, which have made breakthroughs in response to challenges using CNN-based deep learning detection technology in important links of fresh fruit production including fruit flower detection, fruit detection, fruit harvesting, and fruit grading. Object detection based on CNN deep learning was elaborated from data acquisition to model training, and different detection methods based on CNN deep learning were compared in each link of the fresh fruit production. The investigation results of this review show that improved CNN deep learning models can give full play to detection potential by combining with the characteristics of each link of fruit production. The investigation results also imply that CNN-based detection may penetrate the challenges created by environmental issues, new area exploration, and multiple task execution of fresh fruit production in the future.

6.
Front Plant Sci ; 13: 911473, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35747884

RESUMEN

Accurate detection of pear flowers is an important measure for pear orchard yield estimation, which plays a vital role in improving pear yield and predicting pear price trends. This study proposed an improved YOLOv4 model called YOLO-PEFL model for accurate pear flower detection in the natural environment. Pear flower targets were artificially synthesized with pear flower's surface features. The synthetic pear flower targets and the backgrounds of the original pear flower images were used as the inputs of the YOLO-PEFL model. ShuffleNetv2 embedded by the SENet (Squeeze-and-Excitation Networks) module replacing the original backbone network of the YOLOv4 model formed the backbone of the YOLO-PEFL model. The parameters of the YOLO-PEFL model were fine-tuned to change the size of the initial anchor frame. The experimental results showed that the average precision of the YOLO-PEFL model was 96.71%, the model size was reduced by about 80%, and the average detection speed was 0.027s. Compared with the YOLOv4 model and the YOLOv4-tiny model, the YOLO-PEFL model had better performance in model size, detection accuracy, and detection speed, which effectively reduced the model deployment cost and improved the model efficiency. It implied the proposed YOLO-PEFL model could accurately detect pear flowers with high efficiency in the natural environment.

7.
J Org Chem ; 87(2): 1302-1312, 2022 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-35014842

RESUMEN

The merging of visible-light photoredox and acid catalysis allowed for an intramolecular Povarov cycloaddition reaction using eosin Y as the photocatalyst and TsOH·H2O as the co-catalyst. A visible-light-promoted dehydrogenative cyclization protocol enabled the construction of Luotonin A derivatives with up to 97% yield.


Asunto(s)
Estructura Molecular , Catálisis , Ciclización , Oxidación-Reducción , Pirroles , Quinonas
8.
J Org Chem ; 86(21): 14311-14320, 2021 11 05.
Artículo en Inglés | MEDLINE | ID: mdl-34618466

RESUMEN

We report a highly efficient and selective catalytic system, ABNO (9-azabicyclo-[3.3.1]nonane N-oxyl)/HNO3, for the aerobic oxidation of substituted furans to cis-2-ene-1,4-diones under mild reaction conditions using oxygen as the oxidant. The catalyst system is amenable to various substituted (mon-, di-, and tri-) furans and tolerates diverse functional groups, including cyano, nitro, naphthyl, ketone, ester, heterocycle, and even formyl groups. Based on the control and 18O-labeling experiments, the possible mechanism of the oxidation is proposed.


Asunto(s)
Alcoholes , Furanos , Catálisis , Cetonas , Oxidación-Reducción
9.
J Environ Pathol Toxicol Oncol ; 40(3): 87-94, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34587407

RESUMEN

Annexin A9 (ANXA9) represents an important calcium-dependent phospholipid-binding protein family member and contains a calcium-binding site that is necessary for extracellular matrix proteins. ANXA9 has a significant role in human cancers. However, there is no correlation study existing on ANXA9 in gastric cancer (GC). ANXA9 messenger RNA (mRNA) expression within patients with GC were detected with reverse transcription polymerase chain reaction and its protein expression in GC and GES-1 cells were detected through Western blotting. ANXA9 levels within normal and GC tissue samples were measured by Kaplan-Meier analysis and Oncomine. Transwell migration, colony formation, and cell cycle assay monitored the effects of ANXA9 on cell proliferation and metastasis and growth. Additionally, proteins related to epithelial-mesenchymal transition (EMT) were detected to evaluate the function of ANXA9 within GC cells. Relative to GES-1 cells, ANXA9 expression increased within GC cells. Also, ANXA9 expression increased in GC tissues and indicated an unfavorable prognosis. Furthermore, ANXA9 over-expression within HGC-27 cells increased migrated cells quantity and formed larger and more numerous cell clones; the G1 phase decreased while S and G2 phases increased; whereas ANXA9 knockdown suppressed MGC-803 cell growth and migration. Thus, ANXA9 may influence cell growth, migration and EMT through transforming growth factor ß (TGF-ß) signal transduction pathway. Immunofluorescence analyzed SMAD2/3 and p-SMAD2/3 distribution and expression when ANXA9 was overexpressed in HGC-27 cells. These results predicted that ANXA9 mediated cell migration and growth through TGF-ß signal transduction pathway within GC.


Asunto(s)
Anexinas/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patología , Factor de Crecimiento Transformador beta/metabolismo , Anexinas/genética , Línea Celular Tumoral , Movimiento Celular/fisiología , Proliferación Celular/fisiología , Transición Epitelial-Mesenquimal , Humanos , Transducción de Señal , Proteína Smad2/metabolismo , Proteína smad3/metabolismo , Neoplasias Gástricas/mortalidad , Ensayo de Tumor de Célula Madre
10.
Am J Cardiol ; 158: 98-103, 2021 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-34465453

RESUMEN

Comprehensive geriatric assessment (CGA)-based cardiac rehabilitation (CR) program is essential for patients before and after transcatheter aortic valve implantation (TAVI). This study aimed to explore the values of CGA and exercise capacity in CR for patients referred to TAVI. A retrospective analysis was conducted in 90 patients referred to TAVI from January to October 2019. CR strategies started before TAVI. The association between clinical characteristics, CGA, and change in six-minute walk distance (Δ6MWD) was analyzed with multivariate regression models. Most of patients had cognitive impairment (50%), malnutrition (61%), and frailty (83%). After the CR, the proportion of cognitive impairment, malnutrition, and frail patients was significantly decreased by 21%, 40%, and 57%, respectively (p = 0.002, p <0.001, p <0.001). The 6MWD at a month after discharge (291.9 ± 98.8 m) was significantly improved than that at discharge after TAVI (218.8 ± 114.3m, p <0.001). The multivariate regression analysis indicated body mass index (BMI; Δ6MWD:12.0, 95% confidence interval [CI] 0.3 to 23.8, p = 0.045), frailty (Δ6MWD: -57.9, 95% CI -81.8 to -34.1, p <0.001) and malnutrition (Δ6MWD: -25.1, 95% CI -47.0 to -3.2, p = 0.026) as the associated predictors of Δ6MWD. In conclusion, functional status in patients referred to TAVI could be improved by CGA-based CR. BMI, frailty, and malnutrition were associated with the efficacy of CR on exercise capacity. CGA can play the important role in the evaluation and making strategies for CR in patients.


Asunto(s)
Estenosis de la Válvula Aórtica/fisiopatología , Estenosis de la Válvula Aórtica/rehabilitación , Rehabilitación Cardiaca , Tolerancia al Ejercicio/fisiología , Evaluación Geriátrica , Reemplazo de la Válvula Aórtica Transcatéter/rehabilitación , Anciano , Anciano de 80 o más Años , Estenosis de la Válvula Aórtica/cirugía , Femenino , Humanos , Masculino , Estudios Retrospectivos , Prueba de Paso
11.
Ann Noninvasive Electrocardiol ; 26(5): e12880, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34310813

RESUMEN

BACKGROUND: Several ECG criteria have been widely used for diagnosis of left ventricular hypertrophy (LVH) in clinical practice. However, their performance in a general Chinese population is limited. METHODS AND RESULTS: A multi-stage, stratified cluster sampling across China was performed and 7415 representative Chinese adults aged 18-85 years were analyzed. ECG was collected by using GE MAC 5500 machine. The association between five ECG-LVH criteria (i.e., Peguero-Lo Presti, Cornell, Cornell product, Sokolow-Lyon and Sokolow-Lyon product) and echocardiographic LVH (Echo-LVH) was assessed by Pearson's correlation, diagnostic statistics like predictive values, and receiver operating characteristics (ROC) curve. We found that the prevalence of the Echo-LVH was 11% while ECG-LVH ranged from 3% to 27%. All ECG-LVH criteria had high negative predictive value (NPV) (89%) and specificity (73-96%) but low positive predictive value (PPV) (12-24%) and sensitivity (4-29%). The newly Peguero-Lo Presti criteria had higher sensitivity (29%) but lower specificity (73%) and accuracy (68%) compared with other criteria. Cornell product had the best diagnostic performance (AUC: 0.59), as well as the highest specificity (96%) and accuracy (86%) but lowest sensitivity (4%). Among single-lead components of ECG criteria, RaVL voltage and QRS duration performed relatively better than others. Hypertensive and older individuals had higher sensitivity but lower specificity and accuracy than their counterparts. CONCLUSION: ECG-LVH criteria had high NPV to detect Echo-LVH. Though with higher sensitivity, Peguero-Lo Presti criteria did not have better diagnostic performance to detect Echo-LVH. RaVL and QRS duration had stronger association with Echo-LVH among all single-lead components.


Asunto(s)
Hipertensión , Hipertrofia Ventricular Izquierda , China/epidemiología , Ecocardiografía , Electrocardiografía , Humanos , Hipertrofia Ventricular Izquierda/diagnóstico por imagen , Hipertrofia Ventricular Izquierda/epidemiología
12.
Org Lett ; 23(4): 1434-1439, 2021 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-33522233

RESUMEN

We report a simple and effective nickel-based catalytic system, NiCl2·6H2O/tBuOK, for the electrophilically activated hydrosilylation of terminal alkenes with primary silanes. This protocol provides excellent performance under mild reaction conditions: exclusive anti-Markovnikov selectivity, broad functional group tolerance (36 examples), and good scalability (TON = 5500). However, the secondary and tertiary silanes are not suitable. Mechanistic studies revealed that this homogeneous catalytic hydrosilylation includes an electrophilically activated Si-H bond process without the generation of nickel hydrides.

13.
J Org Chem ; 86(5): 3697-3705, 2021 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-33464083

RESUMEN

A highly efficient ortho-dearomative cyclization reaction between alkynes and 2-bromo-2-(2-methoxybenzyl)malonate via visible light-induced photoredox catalysis has been reported. In the presence of 1 mol % fac-Ir(ppy)3, a variety of spiro[4.5]deca-1,7,9-trien-6-ones were obtained in moderate to excellent yields under mild conditions. Under the optimized reaction conditions, a sample reaction of 3 mmol scale proceeded smoothly to give the desired products in 84% yield with a low catalyst loading of 0.1 mol %.

14.
Chem Commun (Camb) ; 56(90): 14047-14050, 2020 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-33103670

RESUMEN

A visible-light-initiated intermolecular dearomatization cyclization cascade reaction between alkynes and indole-derived bromides has been explored. This transformation exhibits a wide substrate scope and significant functional group tolerance, providing an efficient way to access a variety of spiroindolenines under mild conditions.

15.
Adv Healthc Mater ; : e2000076, 2020 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-32338462

RESUMEN

There is a great challenge in regenerating osteochondral defects because they involve lesions of both cartilage and subchondral bone, which have remarkable differences in their chemical compositions and biological lineages. Thus, considering the complicated requirements in osteochondral reconstruction, a biomimetic biphasic osteochondral scaffold (BBOS) with the layer-specific release of stem cell differentiation inducers are developed. The cartilage regeneration layer (cartilage scaffold, CS) in the BBOS contains a hyaluronic acid hydrogel to mimic the composition of cartilage, which is mechanically enhanced by host-guest supramolecular units to control the release of kartogenin (KGN). Additionally, a 3D-printed hydroxyapatite (HAp) scaffold releasing alendronate (ALN) is employed as the bone-regeneration layer (bone scaffold, BS). The two layers are bound by semi-immersion and could regulate the hierarchical targeted differentiation behavior of the stem cells. Compared to the drug-free scaffold, the MSCs in the BBOS could be promoted to differentiate into both chondrocytes and osteoblasts. The in vivo results demonstrate the strong promotion of cartilage or bone regeneration in their respective layers. It is expected that this BBOS with layer-specific inducer release can become a new strategy for osteochondral regeneration.

16.
Org Lett ; 22(2): 528-532, 2020 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-31908167

RESUMEN

A visible-light-driven regioselective dearomative cyclization between 2-benzyl-2-bromomalonate and alkynes under mild conditions leading to the formation of spiro[4,5]decanes has been developed. In the presence of H2O, a variety of 2-benzyl-2-bromomalonates smoothly undergo 5-exo-dig radical dearomative cyclization with alkynes to afford the corresponding spiro[4,5]decanes in moderate to good yield in a step-economical manner under oxidant-free conditions.

17.
Org Biomol Chem ; 18(2): 263-271, 2020 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-31829389

RESUMEN

Polycyclic indole scaffolds are ubiquitous in pharmaceuticals and natural products and in materials science. Here, we present a visible-light-initiated intramolecular aryl migration/desulfonylation/cyclization cascade reaction for the synthesis of tetracyclic indolo[2,1-a]isoquinolin-6(5H)-ones. This protocol not only exhibited a wide substrate scope but also provided a mild route to access a variety of tetracyclic N-fused indoles.

18.
J Org Chem ; 84(24): 16086-16094, 2019 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-31736310

RESUMEN

The asymmetric hydrogenation of 2,4-pentadien-1-ones has been achieved by using trans-RuCl2[(R)-XylylSunPhos][(R)-Daipen] as a catalyst under basic conditions. This hydrogenation demonstrated exclusive C1-carbonyl selectivity, and thus the conjugated 2,4-diene motifs remained untouched, which provides a synthetically useful method for various chiral 2,4-pentadien-1-ols.

19.
Chem Commun (Camb) ; 55(79): 11900-11903, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31528936

RESUMEN

A visible-light-induced radical cascade cyclization of aryl isonitriles and cyclobutanone oxime esters for the synthesis of cyclopenta[b]quinoxalines has been accomplished for the first time. The key to the success of this process was the integration of the in situ-formed nitrile radical followed by the cascade radical isonitrile/nitrile insertion-cyclization. The easy introduction of substituents for both substrates and the high functional group tolerance of the reaction make it an efficient strategy to give various quinoxaline derivatives in moderate to good yields.

20.
J Orthop Surg Res ; 14(1): 299, 2019 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-31488174

RESUMEN

PURPOSE: Our purpose was to combine intravoxel incoherent motion diffusion-weighted MR imaging (IVIM-DWI) and magnetic resonance spectroscopy (MRS) to differentiate osteoporotic fractures from osteolytic metastatic vertebral compression fractures (VCFs). METHODS: A total of 70 patients with VCFs were included and divided into two groups, according to their causes of fractures based on pathological findings or clinical follow-up. All patients underwent conventional sagittal T1WI, T2WI, STIR, IVIM-DWI, and single-voxel MRS. The diffusion coefficient (D), pseudo diffusion (D*), and perfusion fraction (f) parameters from IVIM-DWI and the lipid water ratio (LWR) and fat fraction (FF) parameters from MRS were obtained and compared among groups. Furthermore, the diagnostic performance of MRS, IVIM-DWI, and IVIM-DWI combined with MRS for differentiation between osteoporotic and osteolytic metastatic VCFs was assessed by using receiver operating characteristic (ROC) curve analysis. RESULTS: Compared with the osteoporotic group, the metastatic group had significantly lower values for f, D, and FF, but higher D* (all P < 0.05). The area under the receiver operating characteristic (ROC) curve of MRS, IVIM-DWI, and IVIM-DWI combined with MRS were 0.73, 0.88, and 0.94, respectively. Among these, the IVIM-DWI combined with MRS showed the highest sensitivity, specificity, and accuracy, which are 90.63% (29/32), 97.37 % (37/38), and 94.29% (66/70), respectively. CONCLUSIONS: IVIM-DWI combined with MRS can be more accurate and efficient for differentiation between osteoporotic and osteolytic metastatic VCFs than single MRS or IVIM-DWI.


Asunto(s)
Imagen de Difusión por Resonancia Magnética/métodos , Fracturas por Compresión/diagnóstico por imagen , Espectroscopía de Resonancia Magnética/métodos , Fracturas Osteoporóticas/diagnóstico por imagen , Fracturas de la Columna Vertebral/diagnóstico por imagen , Neoplasias de la Columna Vertebral/diagnóstico por imagen , Anciano , Diagnóstico Diferencial , Imagen de Difusión por Resonancia Magnética/normas , Femenino , Fracturas por Compresión/metabolismo , Humanos , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/lesiones , Vértebras Lumbares/metabolismo , Espectroscopía de Resonancia Magnética/normas , Masculino , Persona de Mediana Edad , Fracturas Osteoporóticas/metabolismo , Fracturas de la Columna Vertebral/metabolismo , Neoplasias de la Columna Vertebral/metabolismo , Vértebras Torácicas/diagnóstico por imagen , Vértebras Torácicas/lesiones , Vértebras Torácicas/metabolismo
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