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Chalcones and dihydrochalcones (DHCs) are important bioactive natural products (BNPs) isolated from traditional Chinese medicine. In this study, 13 chalcones were designed with the inspiration of Loureirin, a DHC extracted from Resina Draconis, and synthesized by classical Claisen-Schmidt reactions. Afterwards the reduction reactions were carried out to obtain the corresponding DHCs. Cytotoxicity assay indicated chalcones and DHCs possessed selective cytotoxicity against colorectal cancer (CRC) cells. The preliminary structure-activity relationships (SAR) of these compounds suggested the α, ß-unsaturated ketone of the chalcones were crucial for the anticancer activity. Interestingly, compounds 3d and 4c exhibited selective anticancer activity against CRC cell line HCT116 with IC50s of 8.4 and 17.9 µM but not normal cell. Moreover, 4c could also inhibit the migration and invasion of CRC cells. Mechanism investigations showed 4c could induce cell cycle G2/M arrest by regulating cell cycle-associated proteins and could also up-regulate Fas cell surface death receptor. The virtual docking further pointed out that compounds 3d and 4c could nicely bind to the Fas/FADD death domain complex (ID: 3EZQ). Furthermore, silencing of Fas significantly enhanced the proliferation of CRC cells and attenuated the cytotoxicity induced by 4c. These results suggested 4c exerted its anticancer activity possibly regulating cell cycle and Fas death receptor. In summary, this study investigated the anticancer activity and mechanism of Loureirin analogues in CRC, suggesting these compounds may warrant further investigation as promising anticancer drug candidates for the treatment of CRC.
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Antineoplásicos , Chalconas , Neoplasias Colorrectales , Receptor fas , Humanos , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/metabolismo , Chalconas/farmacología , Chalconas/química , Antineoplásicos/farmacología , Antineoplásicos/química , Receptor fas/metabolismo , Relación Estructura-Actividad , Células HCT116 , Simulación del Acoplamiento Molecular , Movimiento Celular/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Línea Celular TumoralRESUMEN
Diversity-oriented synthesis strategy for the efficient assembly of indole-fused polycyclic scaffolds via rhodium-catalyzed NH-indole-directed C-H coupling with propargylic alcohol derivatives in a regioselective manner was developed. Five 2-phenyl-1H-indole-embedded core skeletons were synthesized. In particular, three different indole-fused exo-olefin-containing polycycles were realized, which may be manipulated for further chemistry.
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The cascade electrochemical C3-selective aerobic oxygenation of 2-substituted indoles and electrochemical [5 + 3] annulation with amidines through an undivided cell galvanostatic method employing molecular oxygen and "electricity" as green oxidants was developed. This protocol provides an efficient and direct approach to eight-membered benzo[1,3,5]triazocin-6(5H)-ones. Mechanistic studies suggested that two subsequent electrochemical processes both proceeded through radical pathways.
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The electrocatalytic carbon dioxide reduction (CO2RR) is one of the emerging technologies that can effectively transform carbon dioxide (CO2) into valuable products. Electrocatalysts deriving from green synthesis methods will significantly help to establish a new green carbon cycle. Herein, a green electrodeposition method without additional reducing agents was used to synthesize Cu-Ag bimetallic catalysts, and it is shown that the combination of Cu and Ag obviously affects the morphology of the Cu-Ag catalysts, resulting in the formation of elaborate tree-like Cu-Ag clusters. An as-deposited Cu-Ag/carbon fiber (Cu-Ag/CF) catalyst exhibits high activity, selectivity and stability toward the CO2RR; in particular, the elaborate dendritic Cu-Ag/CF can efficiently reduce CO2 to syngas with high selectivity (Faradaic efficiency (FE) > 95%) at a low onset potential (-0.5 V). This work provides a rational strategy to overcome the significantly different reaction capacities during the reduction of Ag+ and Cu2+, leading to the formation of a controlled morphology of Cu-Ag, which is favourable for the design and development of highly efficient Cu or Ag catalysts via green methods for electrocatalyzing the CO2RR.
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Cutaneous endometriosis, characterized by the presence of endometrium or endometrial-like tissue outside of the uterine cavity, is an uncommon and chronic disease. Depending on a patient's history, cutaneous endometriosis is classified as either primary cutaneous endometriosis (PCE) or secondary cutaneous endometriosis (SCE). We report a case of SCE presenting with the classic triad of previous caesarean section, subcutaneous nodules at the site of the scar, and pain associated with menstruation. Considering histopathology as the standard, we confirmed a diagnosis of cutaneous endometriosis by ultrasound and histopathology. Furthermore, we compared and analyzed the clinical characteristics of PCE and SCE, the study included 20 and 14 patients with cutaneous endometriosis diagnosed with PCE and SCE respectively. In the PCE group, the mean age of patients at the onset was 33.7 years, while it was 40.6 years in the SCE group. The mean disease-duration time of PCE was shorter than that of SCE (1.3 vs. 2.8 years, P > 0.05). The most common clinical presentation of PCE and SCE was a nodule (90% vs. 86%). The PCE was mainly bleeding with pain (45%), whereas the SCE of only pain and bleeding with pain accounted for the same proportion (45%). The most common sites of PCE and SCE were in the umbilical region (90% vs. 57%, P < 0.05). In our study, some statistically significant difference was found between different types of CE and it may contribute to improve clinicians' understanding of the disease, and perform early diagnosis and treatment.
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A rhodaelectro-catalyzed C2-H selectively decarboxylative alkenylation of 3-carboxy-1H-indoles employing electricity as the traceless terminal oxidant has been accomplished. The weakly coordinating carboxyl group serves as the traceless directing groups. External oxidant-free in an undivided cell with constant current in aqueous solution ensures the decarboxylative C-H alkenylation to be viable and sustainable.
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We have developed an original blue-light mediated iron-catalyzed oxy-phosphinylation of activated alkenes by secondary phosphine oxides under air at room temperature. Various ß-ketophosphine oxides were then obtained in 43-97 % isolated yields. Control experiments revealed that radical process is involved in the mechanism.
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Psoriasis is an immune-mediated chronic, relapsing, inflammatory, systemic disease induced by a combination of genetics and environment. Currently, there are limited reports on the epidemiological and clinical characteristics of geriatric psoriatic patients in mainland China. This study analyzed the epidemiological characteristics, clinical features, and comorbidity rates of geriatric patients with psoriasis and evaluated the influence of age of onset on disease characteristics. This retrospective study enrolled 1259 geriatric patients with psoriasis in hospitals affiliated with the National Standardized Psoriasis Diagnosis and Treatment Center in China from September 2011 to July 2020 to analyze the epidemiological characteristics, clinical features, and prevalence of comorbidity in geriatric psoriasis. The cases were classified according to the age of onset into two groups to compare differences: early-onset psoriasis (EOP) and late-onset psoriasis (LOP). The mean age of geriatric patients with psoriasis was 67, with a 1.8:1 male-to-female ratio and 10.7% positive family history. The clinical manifestations of plaque psoriasis accounted for a high proportion (82.0%) and 85.1% of patients had moderate to severe disease. Overweight (27.8%), hypertension (18.0%), joint involvement (15.8%), diabetes (13.7%), and coronary heart disease (4.0%) were the first five common comorbidities. The LOP group had significantly more patients (79.9%) than the EOP group (20.1%). Positive family history was significantly associated with the EOP group (21.7%) than the LOP group (7.9%). The scalp (60.2%) was the most affected area, followed by the nails (25.3%), palmoplantar region (25.0%), and genitals (12.7%). This study analyzed the epidemiological and clinical characteristics of geriatric psoriasis in China and found that age of onset had no effect on disease characteristics or other comorbidities, except for toenail involvement, diabetes, and joint damage.
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Diabetes Mellitus , Psoriasis , Humanos , Masculino , Femenino , Anciano , Estudios Retrospectivos , Edad de Inicio , Psoriasis/epidemiología , Psoriasis/diagnóstico , Comorbilidad , Diabetes Mellitus/epidemiologíaRESUMEN
Pristine fullerene C60 is an excellent electron transport material for state-of-the-art inverted structure perovskite solar cells (PSCs), but its low solubility leaves thermal evaporation as the only method for depositing it into a high-quality electron transport layer (ETL). To address this problem, we herein introduce a highly soluble bowl-shaped additive, corannulene, to assist in C60 -assembly into a smooth and compact film through the favorable bowl-ball interaction. Our results show that not only corannulene can dramatically enhance the film formability of C60 , it also plays a critical role in forming C60 -corannulene (CC) supramolecular species and in boosting intermolecular electron transport dynamics in the ETL. This strategy has allowed CC devices to deliver high power conversion efficiencies up to 21.69 %, which is the highest value among the PSCs based on the solution-processed-C60 (SP-C60 ) ETL. Moreover, the stability of the CC device is far superior to that of the C60 -only device because corannulene can retard and curb the spontaneous aggregation of C60 . This work establishes the bowl-assisted ball assembly strategy for developing low-cost and efficient SP-C60 ETLs with high promise for fully-SP PSCs.
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ABSTRACT: Cutaneous meningioma, characterized by ectopic meningothelial cells in the dermis or subcutis, is a rare neoplasm. Generally, the most common location for cutaneous meningioma is the scalp. We report a case of cutaneous meningioma presenting as soft, light red, atrophic, and smooth patches with central blue spots. On histological examination, the tumor consisted largely of epithelioid cells, whorls, nests, and syncytial sheets of meningothelial cells. HMB-45, Melan-A, and S100 were negative; epithelial membrane antigen and somatostatin receptor 2 were positive. Ultimately, histopathologic examination and immunohistochemistry results supported a diagnosis of cutaneous meningioma. In addition, dermal dysplasia was observed above the tumor, manifested by thinning of the dermis and loss of appendages. No abnormalities were found on brain magnetic resonance imaging. Cutaneous meningioma is an extremely rare tumor, and its manifestation as an atrophic patch is even rarer. There have been mainly clinical reports of cutaneous meningioma. This was a rare case of focal aplasia cutis congenita with cutaneous meningioma. For cutaneous meningioma to be diagnosed earlier, there needs to be greater public awareness about the condition.
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Displasia Ectodérmica , Neoplasias Meníngeas , Meningioma , Neoplasias del Sistema Nervioso Periférico , Neoplasias Cutáneas , Humanos , Meningioma/patología , Neoplasias Cutáneas/patología , Displasia Ectodérmica/patología , Neoplasias Meníngeas/patologíaRESUMEN
Purpose: Procrastination has become a pervasive phenomenon in the workplace, yet knowledge of its antecedents remains limited. Therefore, this study explains when and why employees procrastinate. As procrastination is an individual intentional behavior to escape potential resource loss by taking actions to relax; this study regards procrastination as resource-protection behavior. Building on the conservation of resources (COR) theory, the purpose of the current study is to explore the direct impact of external situational factors (ie, stressor appraisals) and individual traits (ie, personality) and their interactive effect on workplace procrastination behavior. Participants and Methods: The study adopts a quantitative approach and uses two-wave data. Data was collected through the randomized cluster sampling technique and a structured questionnaire survey. The sample consisted of civil servants in an organization located in the Shandong province of China. Received 347 valid questionnaires representing an overall response rate of 87%. The theoretical model was tested through confirmatory factor analysis and regression analyses using Mplus 7.2. Results: The results show that hindrance stressor appraisal is positively related to procrastination, whereas challenge stressor appraisal is negatively related to procrastination. Neuroticism had a positive relationship with procrastination, while conscientiousness had a negative relationship with procrastination. Conscientiousness moderates the relationship between challenge stressor appraisal and procrastination such that the relationship is salient under high conscientiousness. Conclusion: Overall, our study suggests that procrastination is affected by personal traits and workplace stressor appraisals. This study makes potential contributions to employees' procrastination literature by and its understanding within the job procrastination knowledge base. Also, this study confirms the comprehensive reach and applicability of the COR theory developed by scholars such as Hobfoll (1989). In practically, the research benefits organizations by providing suggestions for managing employees' procrastination behavior.
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BACKGROUND: Chondroid syringoma (CS) is a rare tumor of the apocrine or eccrine glands. CS of the lower back is rare, and its clinical manifestations are similar to those of lipoma, which is a common misdiagnosis for this disease. CASE SUMMARY: A 39-year-old woman presented with a 2-year history of an asymptomatic subcutaneous mass on the lower back. The lesions increased progressively over time. The patient denied any history. Dermatological examination showed that there was a subcutaneous mass, ranging from 3-4 cm in diameter, with a clear boundary on the lower back. The surface of the skin was smooth without ulceration or scaling. Histopathologic examination was consistent with the diagnosis of CS. CONCLUSION: CS is a rare tumor of the apocrine or eccrine glands. It usually presents as a wellcircumscribed and single subcutaneous masses. Histopathology showed the tumor was located in the dermis, with nests, sheets, and cords of basal-like cells, mucin deposition, and chondroid structures. We herein report a case of CS located in the lower back. CS of the lower back is rare, and its clinical manifestations are similar to those of lipoma, for which it is commonly misdiagnosed.
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Chemodivergent synthesis of indeno[1,2-b]indoles and isoindolo[2,1-a]indoles from the same starting materials involving radical cross-dehydrogenative couplings have been developed. Mn(OAc)3·2H2O selectively promoted an intramolecular radical C-H/C-H dehydrogenative coupling reaction to provide indeno[1,2-b]indoles, while an intramolecular radical C-H/N-H dehydrogenative coupling reaction could proceed via electrochemistry to deliver isoindolo[2,1-a]indoles. Plausible mechanisms of the chemodivergent reactions were proposed.
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An approach to electrochemical oxygenation of indoles leading to isatins was developed by merging with a complementary cathode oxygen reduction reaction. The features of this green protocol include the use of molecular oxygen as the sole oxidant, it being free of an electron transfer mediator, and gram-scale preparation. Mechanistic studies suggested a radical process, and the two oxygen atoms in the isatins were both most likely from molecular oxygen. A detailed mechanism of the reaction utilizing density functional theory calculations was elucidated.
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Indoles , Isatina , Transporte de Electrón , Electrones , Indoles/química , Isatina/química , Oxígeno/químicaRESUMEN
Procrastination is a prevalent phenomenon in organizations, yet limited knowledge is available on how situational antecedents influence it. Based on the conservation of resource theory, we explore how and when perceived red tape influences public sector employees' procrastination behavior. Using survey data of 751 public sector employees from China, we revealed that perceived red tape is positively associated with procrastination behavior, and role overload partially mediates the relationship between perceived red tape and procrastination behavior. Employees' perceived overqualification augments the relationship between role overload and procrastination. Further, the moderated mediation model test illuminates that the indirect effect of perceived red tape on procrastination through role overload depends on perceived overqualification, which means that higher perceived overqualification amplifies the indirect effect. Our research enriches the literature on public sector employees' procrastination behavior.
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Procrastinación , Negociación , Organizaciones , Sector Público , Encuestas y CuestionariosRESUMEN
We developed and tested a moderated mediation model of the relationship between authoritarian leadership and employees' task performance as well as their affective organizational commitment. Analyses of multilevel, multisource, and three-wave data from 99 supervisors and 341 subordinates showed that leader effectiveness evaluations mediated the time-lagged relationship of authoritarian leadership with employees' task performance and affective organizational commitment. Moreover, when leader capability is high, it mitigates the negative relationship between AL and employees' outcomes. Furthermore, the leader capability moderates the indirect relationship of authoritarian leadership with employees' task performance and affective organizational commitment via leader effectiveness evaluation. This study contributes to leadership research and extends our understanding of how and under what circumstances AL is less detrimental to employees' workplace outcomes.
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Liderazgo , Lugar de Trabajo , Humanos , Lugar de Trabajo/psicología , Negociación , InvestigadoresRESUMEN
How leaders influence followers have been a hot topic in both research and practice. Yet, prior studies have primarily focused on the impact of one leadership style, while overlooking how a leadership role may influence behavioral expressions of leaders. Particularly, being a leader means having to face time demands and workload pressure, and thus, busyness becomes a common phenomenon for leaders. Focused on perceived leader busyness, we had examined how it may influence employee interactions with leaders and how those interactions influenced leader evaluations of the performance of followers. Based on sensemaking theory, we propose that when followers have a high level of perspective taking, they are more likely to take avoidance behavior when perceiving leaders as of high busyness. Further, when followers engage in interaction avoidance behavior, leaders may consider followers as hiding errors or intentionally concealing their work process, which reduces positive evaluations (i.e., task performance and conscientiousness evaluation) while enhancing negative evaluation (i.e., deviance behavior) toward followers. We conducted two studies. Study one was conducted with a 25 participants interview and data of 297 employees to show scale validity of perceived leader busyness. Study two was conducted with 377 employees and their direct supervisors. Applying the complex modeling method, we found that followers with low-level perspective taking are less likely to engage in interaction avoidance behavior, even when perceiving leaders as high busyness; interaction avoidance behavior of followers has a positive relationship with counterproductive behavior evaluation of leaders, but a negative relationship with conscientiousness behavior evaluation. This study enriches the dyadic interactions between leaders and followers. In addition, it also shows the burden of perspective taking.
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We report herein the facile synthesis of indole-fused six-, seven-, or eight-membered N,O-heterocycles through rhodium-catalyzed C-H acetoxylation/hydrolysis/annulation. The notable features of this method include C-H acetoxylation using NH-indole as the intrinsic directing group, high functional group compatibility, and construction of indole-fused medium-sized rings.