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BACKGROUND: Quinoa leaves demonstrate a diverse array of colors, offering a potential enhancement to landscape aesthetics and the development of leisure-oriented sightseeing agriculture in semi-arid regions. This study utilized integrated transcriptomic and metabolomic analyses to investigate the mechanisms underlying anthocyanin synthesis in both emerald green and pink quinoa leaves. RESULTS: Integrated transcriptomic and metabolomic analyses indicated that both flavonoid biosynthesis pathway (ko00941) and anthocyanin biosynthesis pathway (ko00942) were significantly associated with anthocyanin biosynthesis. Differentially expressed genes (DEGs) and differentially accumulated metabolites (DAMs) were analyzed between the two germplasms during different developmental periods. Ten DEGs were verified using qRT-PCR, and the results were consistent with those of the transcriptomic sequencing. The elevated expression of phenylalanine ammonia-lyase (PAL), chalcone synthase (CHS), 4-coumarate CoA ligase (4CL) and Hydroxycinnamoyltransferase (HCT), as well as the reduced expression of flavanone 3-hydroxylase (F3H) and Flavonol synthase (FLS), likely cause pink leaf formation. In addition, bHLH14, WRKY46, and TGA indirectly affected the activities of CHS and 4CL, collectively regulating the levels of cyanidin 3-O-(3'', 6''-O-dimalonyl) glucoside and naringenin. The diminished expression of PAL, 4CL, and HCT decreased the formation of cyanidin-3-O-(6"-O-malonyl-2"-O-glucuronyl) glucoside, leading to the emergence of emerald green leaves. Moreover, the lowered expression of TGA and WRKY46 indirectly regulated 4CL activity, serving as another important factor in maintaining the emerald green hue in leaves N1, N2, and N3. CONCLUSION: These findings establish a foundation for elucidating the molecular regulatory mechanisms governing anthocyanin biosynthesis in quinoa leaves, and also provide some theoretical basis for the development of leisure and sightseeing agriculture.
Subject(s)
Anthocyanins , Chenopodium quinoa , Anthocyanins/metabolism , Chenopodium quinoa/genetics , Chenopodium quinoa/metabolism , Gene Expression Profiling/methods , Transcriptome , Plant Leaves/genetics , Plant Leaves/metabolism , Glucosides , Gene Expression Regulation, PlantABSTRACT
ConspectusAtropisomers bearing a rotation-restricted axis are common structural units in natural products, chiral ligands, and drugs; thus, the prevalence of asymmetric synthesis has increased in recent decades. Research into atropisomers featuring an N-containing axis (N-X atropisomers) remains in its infancy compared with the well-developed C-C atropisomer analogue. Notably, N-X atropisomers could offer divergent scaffolds, which are extremely important in bioactive molecules. The asymmetric synthesis of N-X atropisomers is recognized as both appealing and challenging. Recently, we devoted our efforts to the catalytic asymmetric synthesis of N-X atropisomers, benzimidazole-aryl N-C atropisomers, indole-aryl N-C atropisomers, hydrogen-bond-assisted N-C atropisomers, pyrrole-pyrrole N-N atropisomers, pyrrole-indole N-N atropisomers, and indole-indole N-N atropisomers. To obtain the N-C atropisomers, an asymmetric Buchwald-Hartwig reaction of amidines or enamines was employed. Using a Pd(OAc)2/(S)-BINAP or Pd(OAc)2/(S)-Xyl-BINAP catalyst system, benzimidazole-aryl N-C atropisomers and indole-aryl N-C atropisomers were readily obtained. To address the issue of the reduced stability of the diarylamine axis, a six-membered intramolecular N-H-O hydrogen bond was introduced into the N-C atropisomer scaffold. A tandem N-arylation/oxidation process was used for the chiral phosphoric acid (CPA)-catalyzed asymmetric synthesis of N-aryl quinone atropisomers. For N-N atropisomers, a copper-mediated asymmetric Friedel-Crafts alkylation/arylation reaction was developed. The desymmetrization process was completed successfully via a Cu(OTf)2/chiral bisoxazoline or (CuOTf)·Tol/bis(phosphine) dioxide system, thereby achieving the first catalytic asymmetric synthesis of N/N bipyrrole atropisomers. Asymmetric Buchwald-Hartwig amination of enamines was utilized to provide N-N bisindole atropisomers with excellent stereogenic control. This was the first asymmetric synthesis of N-N atropisomers featuring a bisindole structural scaffold using the de novo indole construction strategy. The asymmetric N-N heterobiaryl atropisomer synthesis was substantially facilitated using palladium-catalyzed transient directing group (TDG)-mediated C-H functionalization. Atropisomeric alkenylation, allylation, or alkynylation was accomplished using the Pd(OAc)2/l-tert-leucine system. Herein, we summarize our work on the palladium-, copper-, and CPA-catalyzed asymmetric syntheses of N-C and N-N atropisomers. Furthermore, the application of our work in the synthesis of bioactive molecule analogues and axially chiral ligands is demonstrated. Subsequently, the stability of the chiral N-containing axis is briefly discussed in terms of single crystals and obtained rotational barriers. Finally, an outlook on the asymmetric N-X atropisomer synthesis is provided.
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OBJECTIVE: Anterior disc displacement (ADD) is a common clinical issue and may cause osteoarthritis (OA). However, the research of protein changes in synovial fluid as disease development marker and potential treatment clue is still insufficient. MATERIALS AND METHODS: We conducted the high-resolution mass spectrometry (MS) of synovial fluid collected from 60 patients with normal disk position to ADD and ADD with osteoarthritis (OA). The proteins with significant changes among the 3 groups were analyzed by biological information and further validated by in primary rat condyle chondrocytes and OA animal model. RESULTS: FGL2, THBS4, TNC, FN1, OMD etc. were significantly increased in ADD without OA (p < 0.05), which reflected the active extracellular matrix and collagen metabolism. FGFR1, FBLN2, GRB2 etc. were significantly increased in ADD with OA group (p < 0.05), which revealed an association with apoptosis and ferroptosis. Proteins such as P4HB, CBLN4, FHL1, VIM continuously increase in the whole disease progress (p < 0.05). Both the in vitro and in vivo results are consistent with protein changes detected in MS profile. CONCLUSION: This study firstly provides the expression changes of proteins from normal disc condyle relationship toward ADD with OA, which can be selected and studied further as disease progress marker and potential treatment targets.
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OBJECTIVE: Unilateral temporomandibular joint ankylosis with jaw deformity (UTMJAJD) may require simultaneous total joint prosthesis (TJP) reconstruction, sagittal split ramus (SSRO), and Le Fort I osteotomies. The purpose of this study was to evaluate outcomes in patients treated with these procedures. METHODS: Patients diagnosed UTMJAJD between 2016 and 2018 were selected for the study. Mandible-first procedure was performed after ankylosis release with TJP on the ankylosed side and SSRO on the contralateral side. Le Fort I osteotomy with and without genioplasty was lastly performed. Maximal incisor opening (MIO), facial symmetry, and jaw and condyle stability were compared before, after operation, and during follow-ups. RESULTS: Seven patients were included in the study. Their average chin deviation was 9.5 ± 4.2 mm, and maxillary cant was 5.1 ± 3.0°. After operation, jaw deformity significantly improved, with chin deviation corrected 7.6 ± 4.1 mm (p = 0.015) and advanced 5.9 ± 2.5 mm (p = 0.006). After an average follow-up of 26.6 ± 17.1 months, MIO significantly increased from 11.4 ± 9.3 to 35.7 ± 2.6 mm (p = 0.000). The occlusion was stable with no significant positional or rotational changes of the jaw (p > 0.05). There was no obvious condylar resorption during follow-ups. CONCLUSION: Simultaneous TJP reconstruction, SSRO, and Le Fort I osteotomy are reliable and effective methods for the treatment of UTMJAJD.
Subject(s)
Ankylosis , Dental Implants , Jaw Abnormalities , Joint Prosthesis , Temporomandibular Joint Disorders , Humans , Mandibular Condyle , Cohort Studies , Osteotomy/methods , Mandible/surgery , Polymers , Ankylosis/surgery , Temporomandibular Joint , Osteotomy, Le Fort/methods , Osteotomy, Sagittal Split Ramus/methodsABSTRACT
OBJECTIVES: To evaluate the effects of costochondral grafting (CCG) used for temporomandibular joint ankylosis (TMJA) in growing patients. MATERIALS AND METHODS: Pediatric patients with TMJA treated by CCG from 2010.5 to 2021.7 were included in the study. CT scans were performed before and after operations with at least 1 year follow-up. The height of the mandibular ramus, menton deviation or retraction, osteotomy gap, etc. were measured by ProPlan CMF1.4 software. CCG growth, resorption, and relapse were evaluated and analyzed with influencing factors such as age, ostectomy gap, etc. by generalized estimating equation. RESULTS: There were 24 patients (29 joints) with an average age of 6.30 ± 3.13 years in the study. After operation, the mandibular ramus was elongated by 5.97 ± 3.53 mm. Mandibular deviation or retrusion was corrected by 4.82 ± 2.84 mm and 3.76 ± 2.97 mm respectively. After a mean follow-up of 38.91 ± 29.20 months, 58.62% CCG grew (4.18 ± 7.70 mm), 20.69% absorbed (2.23 ± 1.16 mm), and 20.69% re-ankylosed. The re-ankylosis was negatively correlated with the osteotomy gap (OR:0.348,0.172-0.702 95%CI, critical value = 6.10 mm). CCG resorption was positively correlated with the distance of CCG ramus elongation (OR:3.353,1.173-9.586 95%CI, critical value = 7.40 mm). CONCLUSIONS: An adequate osteotomy gap and CCG ramus elongation distance are the key factors for successful treatment of TMJA with jaw deformities in growing patients. CLINICAL RELEVANCE: TMJA affects mouth opening and jaw development in pediatric patients. The most common autogenous bone graft for pediatric patients is CCG due to its growth potential, convenient access and easy contouring. Also, it can simultaneously reconstruct the TMJ and improve jaw deformity by lengthening the mandibular ramus. But the growth of CCG is unpredictable. In this study, we explored several factors that may affect the absorption and re-ankylosis of CCG, expecting to provide several suggestions to improve future CCG treatment.
Subject(s)
Ankylosis , Temporomandibular Joint Disorders , Tomography, X-Ray Computed , Humans , Child , Temporomandibular Joint Disorders/surgery , Temporomandibular Joint Disorders/diagnostic imaging , Female , Ankylosis/surgery , Male , Treatment Outcome , Ribs/transplantation , Bone Transplantation/methods , Child, Preschool , Retrospective Studies , Cartilage/transplantationABSTRACT
BACKGROUND: Symptoms like vaginal bleeding or abdominal pain in early pregnancy can create anxiety about potential miscarriage. Previous studies have demonstrated ultrasonographic variables at the first trimester transvaginal scan (TVS) which can assist in predicting outcomes by 12 weeks gestation. AIM: To validate the miscarriage risk prediction model (MRP) in women who present with a viable intrauterine pregnancy (IUP) at the primary ultrasound. MATERIALS AND METHODS: A multi-centre diagnostic study of 1490 patients was performed between 2011 and 2019 for retrospective external and 2017-2019 for prospective temporal validation. The reference standard was a viable pregnancy at 12 + 6 weeks. The MRP model is a multinomial logistic regression model based on maternal age, embryonic heart rate, logarithm (gestational sac volume/crown-rump length (CRL)) ratio, CRL and presence or absence of clots. RESULTS: Temporal validation data from 290 viable IUPs were collected: 225 were viable at the end of the first trimester, 31 had miscarried and 34 were lost to follow-up. External validation data from 1203 viable IUPs were collected at two other ultrasound units: 1062 were viable, 69 had miscarried and 72 were lost to follow-up. Temporal validation with a cut-off of 0.1 demonstrated: area under the curve (AUC) of 0.8 (0.7-0.9), sensitivity 66.7%, specificity 83.9%, positive predictive value (PPV) 35.7%, negative predictive value (NPV) 94.9%, positive likelihood ration (LR+) 4.1 and negative LR (LR-) 0.4. External validation demonstrated: AUC 0.7 (0.7-0.8), sensitivity 44.9%, specificity 90.4%, PPV 23.3%, NPV 96.2%, LR+ 4.6 and LR- 0.6 (0.4-0.7). CONCLUSION: The MRP model is not able to be used in real time for counselling, and management should be individualised.
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Inherent chirality is used to describe chiral cyclic molecules devoid of central, axial, planar, or helical chirality and has tremendous applications in chiral recognition and enantioselective synthesis. Catalytic and divergent syntheses of inherently chiral molecules have attracted increasing interest from chemists. Herein, we report the enantioselective synthesis of inherently chiral tribenzocycloheptene derivatives via chiral phosphoric acid (CPA)-catalyzed condensation of cyclic ketones and hydroxylamines. This chemistry paves the way to accessing the less stable derivatives of 7-membered rings with inherent chirality. A series of chiral tribenzocycloheptene oxime ethers was synthesized in good yields (up to 97 %) with excellent enantioselectivities (up to 99 % ee).
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Nickel-catalyzed transannulation reactions triggered by the extrusion of small gaseous molecules have emerged as a powerful strategy for the efficient construction of heterocyclic compounds. However, their use in asymmetric synthesis remains challenging because of the difficulty in controlling stereo- and regioselectivity. Herein, we report the first nickel-catalyzed asymmetric synthesis of N-N atropisomers by the denitrogenative transannulation of benzotriazones with alkynes. A broad range of N-N atropisomers was obtained with excellent regio- and enantioselectivity under mild conditions. Moreover, density functional theory (DFT) calculations provided insights into the nickel-catalyzed reaction mechanism and enantioselectivity control.
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The biology and diversity of glomerular parietal epithelial cells (PECs) are important for understanding podocyte regeneration and crescent formation. Although protein markers have revealed the morphological heterogeneity of PECs, the molecular characteristics of PEC subpopulations remain largely unknown. Here, we performed a comprehensive analysis of PECs using single-cell RNA sequencing (scRNA-seq) data. Our analysis identified five distinct PEC subpopulations: PEC-A1, PEC-A2, PEC-A3, PEC-A4 and PEC-B. Among these subpopulations, PEC- A1 and PEC-A2 were characterized as podocyte progenitors while PEC-A4 represented tubular progenitors. Further dynamic signaling network analysis indicated that activation of PEC-A4 and the proliferation of PEC-A3 played pivotal roles in crescent formation. Analyses suggested that upstream signals released by podocytes, immune cells, endothelial cells and mesangial cells serve as pathogenic signals and may be promising intervention targets in crescentic glomerulonephritis. Pharmacological blockade of two such pathogenic signaling targets, proteins Mif and Csf1r, reduced hyperplasia of the PECs and crescent formation in anti-glomerular basement membrane glomerulonephritis murine models. Thus, our study demonstrates that scRNA-seq-based analysis provided valuable insights into the pathology and therapeutic strategies for crescentic glomerulonephritis.
Subject(s)
Glomerulonephritis , Kidney Diseases , Podocytes , Mice , Animals , Endothelial Cells/pathology , Epithelial Cells/metabolism , Kidney Glomerulus/pathology , Podocytes/pathology , Glomerulonephritis/pathology , Proteins/metabolism , Kidney Diseases/pathologyABSTRACT
Herein, the palladium-catalyzed double C-N coupling of 9H-carbazol-9-amines and 2,2'-dibromo-1,1'-biphenyl is reported. This protocol offers access to N,N'-bicarbazole scaffolds, which have frequently been used as linkers in the construction of functional covalent organic frameworks (COFs). A variety of substituted N,N'-bicarbazoles were synthesized in moderate to high yields based on this chemistry, and the potential application of this method was showcased by the synthesis of COF monomers like tetrabromide 4 and tetraalkynylate 5.
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A new thioxanthone-based photocatalyst with a [2.2]paracyclophane skeleton and planar chirality has been developed. The catalyst has been successfully applied in the visible light-mediated enantioselective aza Paternò-Büchi reactions of quinoxalinone and styrenes to produce azetidines. The structures of the catalyst derivatives were unequivocally determined by their single crystal X-ray crystallography analysis.
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Apelin-13 may have neuroprotective effects. We aimed to determine whether serum apelin-13 could serve as a potential biomarker for severity, delayed cerebral ischemia (DCI), and prognosis after human aneurysmal subarachnoid hemorrhage (aSAH). In this prospective, observational, cohort, single-center study of 139 patients with aSAH and 139 healthy individuals, serum apelin-13 levels were determined. The indicators of stroke severity were the Hunt-Hess scale and the modified Fisher grading scale. The prognostic parameters were DCI and 6-month worse prognosis (Extended Glasgow Outcome Scale scores of 1-4). Using binary logistic regression analysis, the relationship between serum apelin-13 levels and prognosis was reported as odds ratios (ORs) with 95% confidence intervals (CIs). Under the receiver operating characteristic curve, prognostic abilities were shown as areas under the curve (AUCs) with 95% CIs. Serum apelin-13 levels were substantially lower in patients than in controls (median, 28.8 versus 48.6 ng/ml; P < 0.001), in patients with DCI than in non-DCI patients (median, 14.9 versus 31.6 ng/ml; P < 0.001), and in patients with worse prognosis than in those with good prognosis (median, 16.3 versus 33.7 ng/ml; P < 0.001). Serum apelin-13 levels were independently correlated with Hunt-Hess scores (beta, -6.836; 95% CI, -8.963-4.708; VIF, 2.219; P = 0.001) and modified Fisher scores (beta, -3.350; 95% CI, -6.151-0.549; VIF, 1.562; P = 0.019). Serum apelin-13 levels were an independent predictor of DCI (OR, 0.951; 95% CI, 0.914-0.990; P = 0.022) and worse prognosis (OR, 0.954; 95% CI, 0.916-0.993; P = 0.013). Serum apelin-13 levels significantly differentiated DCI and poor prognosis, with AUCs of 0.753 (95% CI, 0.656-0.850) and 0.791 (95% CI, 0.713-0.868) respectively. Using the Youden method, serum apelin-13 levels < 19.3 ng/ml distinguished the risk of DCI with 64.7% sensitivity and 77.1% specificity, and serum apelin-13 levels < 30.2 ng/ml discriminated the development of worse prognosis with 89.1% sensitivity and 63.4% specificity. Serum apelin-13 levels combined with Hunt-Hess scores and modified Fisher scores displayed a significantly higher AUC than any one of them for prognostic prediction (all P < 0.05). Decreased serum apelin-13 levels, which are strongly correlated with disease severity, independently predicted poor outcomes following aSAH, substantializing serum apelin-13 as a useful prognostic biomarker of aSAH.
Subject(s)
Subarachnoid Hemorrhage , Humans , Prospective Studies , Prognosis , Cerebral InfarctionABSTRACT
Cynasibirolide A (1), one new humulanolide sesquiterpene, together with four known analogs, asteriscanolide (2), (1S,8S)-8-hydroxyhumula-2Z,6E,9E-trien-1,12-olide (3), (1S,7R)-8-oxohumula-2Z,9E-dien-1,12-olide (4), and (+)-6,7,9,10-tetrahydroasteriscunolide (5) were isolated from the roots and rhizomes of Cynanchum acutum subsp. sibiricum. Their structures and configurations were elucidated by spectroscopic methods, including 2D-NMR techniques, and the structure of 1 was confirmed by single-crystal X-ray diffraction. All compounds were evaluated for their anti-complementary activity inâ vitro, and compound 3 exhibited anti-complement effect with CH50 value of 0.45â mM.
Subject(s)
Cynanchum , Sesquiterpenes , Molecular Structure , Cynanchum/chemistry , Magnetic Resonance Spectroscopy , Plant Roots/chemistry , Sesquiterpenes/chemistryABSTRACT
Surgeons determine the treatment method for patients with epiglottis obstruction based on its severity, often by estimating the obstruction severity (using three obstruction degrees) from the examination of drug-induced sleep endoscopy images. However, the use of obstruction degrees is inadequate and fails to correspond to changes in respiratory airflow. Current artificial intelligence image technologies can effectively address this issue. To enhance the accuracy of epiglottis obstruction assessment and replace obstruction degrees with obstruction ratios, this study developed a computer vision system with a deep learning-based method for calculating epiglottis obstruction ratios. The system employs a convolutional neural network, the YOLOv4 model, for epiglottis cartilage localization, a color quantization method to transform pixels into regions, and a region puzzle algorithm to calculate the range of a patient's epiglottis airway. This information is then utilized to compute the obstruction ratio of the patient's epiglottis site. Additionally, this system integrates web-based and PC-based programming technologies to realize its functionalities. Through experimental validation, this system was found to autonomously calculate obstruction ratios with a precision of 0.1% (ranging from 0% to 100%). It presents epiglottis obstruction levels as continuous data, providing crucial diagnostic insight for surgeons to assess the severity of epiglottis obstruction in patients.
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The development of Dai medicine is relatively slow, and Zanthoxylum has great economic and medicinal value. It is still difficult to obtain medicinal components from the low-polarity parts of Zanthoxylum belonging to Dai medicine. In this study, we introduced one simple and quick strategy of separating target compounds from the barks of Z. acanthopodium var. timbor by high-performance countercurrent chromatography (HPCCC) with an off-line anti-inflammatory activity screening mode. The development of this strategy was based on the TLC-based generally useful estimation of solvent systems (GUESS) method and HPCCC in combination. This paper presented a rapid method for obtaining target anti-inflammatory compounds. Three lignins were enriched by HPCCC with an off-line inhibition mode of nitric oxide production in lipopolysaccharide-stimulated RAW264.7 macrophage cells, using petroleum ether-ethyl acetate-methanol-water (3:2:3:2) as the solvent system. The results showed that this method was simple and practical and could be applied to trace the anti-inflammatory components of the low-polarity part in Dai medicine.
Subject(s)
Plants, Medicinal , Zanthoxylum , Countercurrent Distribution/methods , Lignin/pharmacology , Lignin/analysis , Zanthoxylum/chemistry , Chromatography, High Pressure Liquid/methods , Anti-Inflammatory Agents/pharmacology , Solvents , Plant Extracts/chemistryABSTRACT
BACKGROUND: Temporomandibular joint (TMJ) disc repositioning through open suturing (OSu) is a new disc repositioning method. Its result for adolescents with condylar resorption and dentofacial deformities combined with and without postoperative occlusal splints (POS) has not been well studied. OBJECTIVE: This study was to evaluate and compare the effects of OSu with and without POS in the treatment of TMJ anterior disc displacement without reduction (ADDwoR) in adolescent skeletal Class II malocclusion. METHODS: A total of 60 adolescents with bilateral ADDwoR were enrolled in this study. They were randomly allocated into two groups: OSu with and without POS. Magnetic resonance imaging (MRI) and lateral cephalometric radiographs were used to measure changes in condylar height and the degree of skeletal Class II malocclusion from before operation and at 12 months postoperatively. Changes in these indicators were compared within and between the two groups. RESULTS: After OSu, both groups exhibited significant improvements in condylar height and occlusion at the end of 12 months follow-up (P < 0.05). The group of OSu with POS had significantly more new bone formation (2.83 ± 0.75 mm vs. 1.42 ± 0.81 mm, P < 0.001) and improvement in dentofacial deformity than the group of OSu only (P < 0.05). The new bone height was significantly correlated with POS (P < 0.001), the changes of SNB (P = 0.018), overjet (P = 0.012), and Wits appraisal (P < 0.001). CONCLUSION: These findings indicated that OSu can effectively stimulate condylar regeneration and improve skeletal Class II malocclusion in adolescents with bilateral ADDwoR. The results are better when combined with POS. TRIAL REGISTRATION: This trial was prospectively registered on the chictr.org.cn registry with ID: ChiCTR1900021821 on 11/03/2019.
Subject(s)
Joint Dislocations , Malocclusion, Angle Class II , Temporomandibular Joint Disorders , Adolescent , Humans , Dental Occlusion , Magnetic Resonance Imaging/methods , Malocclusion, Angle Class II/therapy , Malocclusion, Angle Class II/pathology , Occlusal Splints , Temporomandibular Joint , Temporomandibular Joint Disc/diagnostic imaging , Temporomandibular Joint Disc/pathology , Temporomandibular Joint Disorders/diagnostic imaging , Temporomandibular Joint Disorders/therapy , Temporomandibular Joint Disorders/pathologyABSTRACT
Objective To evaluate extrathyroidal extension (ETE) in papillary thyroid microcarcinoma (PTMC) with three-dimensional tomographic ultrasound imaging (3D-TUI). Methods A total of 97 thyroid nodules of 79 patients with PTMC treated in PUMC Hospital from February 2016 to January 2018 were included in this study.Two ultrasound experts performed independent blinded assessment of the relationship between thyroid nodules and thyroid capsule by two-dimensional ultrasound (2D-US) and 3D-TUI.The results of 2D-US and 3D-TUI in evaluating ETE were compared with intraoperative findings and postoperative histological and pathological results. Results Among the 97 nodules,54 (55.7%) nodules had ETE.The diagnostic sensitivity (68.5% vs.37.0%;χ2=10.737,P=0.002),accuracy (74.5% vs.56.7%;χ2=6.686,P=0.015),and area under the receiver operating characteristic curve[0.761 (95%CI=0.677-0.845) vs.0.592 (95%CI=0.504-0.680);Z=3.500,P<0.001] of 3D-TUI were higher than those of 2D-US.However,3D-TUI and 2D-US showed no significant difference in the specificity (84.1% vs.81.4%;χ2=0.081,P=0.776),negative predictive value (67.9% vs.50.7%;χ2=3.645,P=0.066),or positive predictive value (84.1% vs.71.4%;χ2=1.663,P=0.240). Conclusion Compared with 2D-US,3D-TUI demonstrates increased diagnostic efficiency for ETE of PTMC.
Subject(s)
Carcinoma, Papillary , Thyroid Neoplasms , Thyroid Nodule , Humans , Thyroid Neoplasms/diagnosis , Carcinoma, Papillary/pathology , Ultrasonography/methods , Retrospective StudiesABSTRACT
Over the past few decades, the Buchwald-Hartwig reaction has emerged as a powerful tool for forging C-N bonds, and has been vital to the pharmaceuticals, materials, and catalysis fields. However, asymmetric Buchwald-Hartwig amination reactions for constructing centered chirality, planar chirality, and axial chirality remain in their infancy owing to limited substrate scope and laggard ligand design. The recent surge in interest in the synthesis of C-N/N-N atropisomers, has witnessed a renaissance in asymmetric Buchwald-Hartwig amination chemistry as the first practical protocol for the preparation of C-N atropisomers. This review highlights reported asymmetric Buchwald-Hartwig amination protocols and provides a brief overview of their chemical practicality.
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Transition-metal-catalyzed hydroarylation of unsymmetrical internal alkynes remains challenging because of the difficulty in controlling regioselectivity and stereoselectivity. Moreover, the enantioselective hydroarylation of alkynes using organoboron reagents has not been reported. Herein, we report for the first time that palladium compounds can catalyze the hydroarylation of 1-alkynylindoles with organoborons for the synthesis of chiral C-N atropisomers. A series of rarely reported vinylindole atropisomers was synthesized with excellent regio-, stereo- (Z-selectivity), and enantioselectivity under mild reaction conditions. The ready availability of organoborons and alkynes and the simplicity, high stereoselectivity, and good functional group tolerance of this catalytic system make it highly attractive.
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The catalytic asymmetric construction of N-N atropisomeric biaryls remains a formidable challenge. Studies of them lag far behind studies of the more classical carbon-carbon biaryl atropisomers, hampering meaningful development. Herein, the first palladium-catalyzed enantioselective C-H activation of pyrroles for the synthesis of N-N atropisomers is presented. Structurally diverse indole-pyrrole atropisomers possessing a chiral N-N axis were produced with good yields and high enantioselectivities by alkenylation, alkynylation, allylation, or arylation reactions. Furthermore, the kinetic resolution of trisubstituted N-N heterobiaryls with more sterically demanding substituents was also achieved. Importantly, this versatile C-H functionalization strategy enables iterative functionalization of pyrroles with exquisite selectivity, expediting the formation of valuable, complex, N-N atropisomers.