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1.
J Neurosci Methods ; 409: 110217, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38964477

RESUMO

BACKGROUND: Parkinson's patients have significant autonomic dysfunction, early detect the disorder is a major challenge. To assess the autonomic function in the rat model of rotenone induced Parkinson's disease (PD), Blood pressure and ECG signal acquisition are very important. NEW METHOD: We used telemetry to record the electrocardiogram and blood pressure signals from awake rats, with linear and nonlinear analysis techniques calculate the heart rate variability (HRV) and blood pressure variability (BPV). we applied nonlinear analysis methods like sample entropy and detrended fluctuation analysis to analyze blood pressure signals. Particularly, this is the first attempt to apply nonlinear analysis to the blood pressure evaluate in rotenone induced PD model rat. RESULTS: HRV in the time and frequency domains indicated sympathetic-parasympathetic imbalance in PD model rats. Linear BPV analysis didn't reflect changes in vascular function and blood pressure regulation in PD model rats. Nonlinear analysis revealed differences in BPV, with lower sample entropy results and increased detrended fluctuation analysis results in the PD group rats. COMPARISON WITH EXISTING METHODS AND CONCLUSIONS: our experiments demonstrate the ability to evaluate autonomic dysfunction in models of Parkinson's disease by combining the analysis of BPV with HRV, consistent with autonomic impairment in PD patients. Nonlinear analysis by blood pressure signal may help in early detection of the PD. It indicates that the fluctuation of blood pressure in the rats in the rotenone model group tends to be regular and predictable, contributes to understand the PD pathophysiological mechanisms and to find strategies for early diagnosis.

2.
Clin Proteomics ; 21(1): 50, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39004717

RESUMO

BACKGROUND: Estrogen receptor-positive (ER+) breast cancer accounts for two-thirds of all breast cancers, and its early and late recurrences still threaten patients' long-term survival and quality of life. Finding candidate tumor antigens and potential therapeutic targets is critical to addressing these unmet needs. METHOD: The isobaric tags for relative and absolute quantitation (iTRAQ) proteomic analysis was employed to identify the differentially expressed proteins (DEPs) between ER + breast cancer and corresponding adjacent normal tissue. Candidate DEPs were screened by bioinformatic analyses, and their expression was confirmed by immunohistochemical (IHC) staining and western blot. A series of in vitro experiments, including wound healing assay, colony formation, and cell cycle assay, were performed to reveal the functions of selected DEPs. Additionally, their clinical significances were further analyzed. RESULT: A total of 369 DEPs (fold change ≥ 2.0 or ≤ 0.66, P < 0.05) were discovered. Compared with normal tissue, 358 proteins were up-regulated and 11 proteins were down-regulated in ER + breast cancer. GO and KEGG enrichment analysis showed that DEPs were closely associated with RNA regulation and metabolic pathways. STRING analysis found ESF1 and MIPEP were the hub genes in breast cancer, whose increased expressions were verified by the IHC staining and western blot. Knocking down ESF1 and MIPEP inhibited colony formation and increased cell apoptosis. Besides, knocking down ESF1 inhibited wound healing but not MIPEP. In addition, ESF1 and MIPEP expression were negatively associated with patient prognosis. CONCLUSION: The upregulation of ESF1 and MIPEP promoted ER + breast cancer proliferation, which might provide novel targets for the development of new therapies.

3.
Aesthetic Plast Surg ; 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38806829

RESUMO

BACKGROUND: Fat grafting is widely used in breast reconstruction and aesthetic plastic surgery. However, the success rate and effects of fat grafting, especially in elderly female donors, are observed. This study aimed to explore the difference in the survival rate of donor fat from elderly women and young women in fat grafting. METHODS: We collected adipose tissue samples from two healthy Chinese women: a young woman and an elderly woman. In addition, adipose tissue samples were collected from female nude mice in four experimental groups-CON-Y, CON-O, OVX-Y, and OVX-O-after fat transplantation. Grafts were harvested, weighed, and subjected to assessment of histology and angiogenesis. RESULTS: An ovariectomy model was successfully established to validate the effect of low estrogen levels on fat grafting results. Due to the influence of low estrogen levels, the graft survival rate of donor site fat was significantly higher in elderly women than in young women, accompanied by a lesser degree of angiogenesis. Low estrogen levels led to adipocyte hypertrophy, which may be related to decreased AQP-7 expression. CONCLUSIONS: AQP-7 downregulation due to low estrogen levels induces adipocyte hypertrophy, and donor fat from elderly women exhibits a higher survival rate after fat transplantation. LEVEL OF EVIDENCE V: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

4.
World J Diabetes ; 15(5): 958-976, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38766439

RESUMO

BACKGROUND: Synaptotagmins (SYTs) are a family of 17 membrane transporters that function as calcium ion sensors during the release of Ca2+-dependent neurotransmitters and hormones. However, few studies have reported whether members of the SYT family play a role in glucose uptake in diabetic retinopathy (DR) through Ca2+/glucose transporter-1 (GLUT1) and the possible regulatory mechanism of SYTs. AIM: To elucidate the role of the SYT family in the regulation of glucose transport in retinal pigment epithelial cells and explore its potential as a therapeutic target for the clinical management of DR. METHODS: DR was induced by streptozotocin in C57BL/6J mice and by high glucose medium in human retinal pigment epithelial cells (ARPE-19). Bioinformatics analysis, reverse transcriptase-polymerase chain reaction, Western blot, flow cytometry, ELISA, HE staining, and TUNEL staining were used for analysis. RESULTS: Six differentially expressed proteins (SYT2, SYT3, SYT4, SYT7, SYT11, and SYT13) were found between the DR and control groups, and SYT4 was highly expressed. Hyperglycemia induces SYT4 overexpression, manipulates Ca2+ influx to induce GLUT1 fusion with the plasma membrane, promotes abnormal expression of the glucose transporter GLUT1 and excessive glucose uptake, induces ARPE-19 cell apoptosis, and promotes DR progression. Parkin deficiency inhibits the proteasomal degradation of SYT4 in DR, resulting in SYT4 accumulation and enhanced GLUT1 fusion with the plasma membrane, and these effects were blocked by oe-Parkin treatment. Moreover, dysregulation of the myelin transcription factor 1 (Myt1)-induced transcription of SYT4 in DR further activated the SYT4-mediated stimulus-secretion coupling process, and this process was inhibited in the oe-MYT1-treated group. CONCLUSION: Our study reveals the key role of SYT4 in regulating glucose transport in retinal pigment epithelial cells during the pathogenesis of DR and the underlying mechanism and suggests potential therapeutic targets for clinical DR.

5.
Neuroimage ; 290: 120565, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38453102

RESUMO

People tend to perceive the same information differently depending on whether it is expressed in an individual or a group frame. It has also been found that the individual (vs. group) frame of expression tends to lead to more charitable giving and greater tolerance of wealth inequality. However, little is known about whether the same resource allocation in social interactions elicits distinct responses depending on proposer type. Using the second-party punishment task, this study examined whether the same allocation from different proposers (individual vs. group) leads to differences in recipient behavior and the neural mechanisms. Behavioral results showed that reaction times were longer in the unfair (vs. fair) condition, and this difference was more pronounced when the proposer was the individual (vs. group). Neural results showed that proposer type (individual vs. group) influenced early automatic processing (indicated by AN1, P2, and central alpha band), middle processing (indicated by MFN and right frontal theta band), and late elaborative processing (indicated by P3 and parietal alpha band) of fairness in resource allocation. These results revealed more attentional resources were captured by the group proposer in the early stage of fairness processing, and more cognitive resources were consumed by processing group-proposed unfair allocations in the late stage, possibly because group proposers are less identifiable than individual proposers. The findings provide behavioral and neural evidence for the effects of "individual/group" framing leading to cognitive differences. They also deliver insights into social governance issues, such as punishing individual and/or group violations.


Assuntos
Eletroencefalografia , Jogos Experimentais , Humanos , Potenciais Evocados/fisiologia , Interação Social , Punição/psicologia
7.
Phys Rev E ; 107(6-2): 065204, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37464671

RESUMO

Although the plasma-induced receiving and radiating near-field cutoff phenomena in the subwavelength regime are found of crucial importance in electromagnetic (EM) signal transmissions and plasma property studies, their mechanisms to a large extent remain unclear and undistinguished. In this paper, in the perspective of field and energy transfer, it is demonstrated that the cutoff in the near-field regime is completely different from that in the geometric optical regime. Results show that, for the receiving mode, epsilon-near-zero (ENZ) plasmas can be treated as a nearly ideal EM fluid, and thus, EM waves are restricted into the plasma channel. For the radiating mode, on the other hand, it is the destructive interference between the electric dipole fields of the antenna and the ENZ plasma that results in vanishing far-field radiation. As an important supplement to the existing cutoff theories, our results not only offer clearer physical insights into the near-field cutoff effect but also provide a helpful reference for cutoff-related practical applications in various frequency bands.

8.
Brain Sci ; 13(5)2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37239246

RESUMO

The self-to-other model of empathy (SOME) states that a key reason for the empathic deficiency in autistic individuals is the imbalance of the self-other switch. The existing interventions of theory of mind contain training of self-other transposition ability but combined with other cognitive trainings. The self-other distinction brain areas of autistic individuals have been revealed, but the brain areas of the self-other transposition ability and its intervention have not been investigated. There are normalized amplitudes of low-frequency fluctuations (mALFFs) within 0.01-0.1 Hz and many normalized amplitudes of frequency fluctuations (mAFFs) within 0-0.01, 0.01-0.05, 0.05-0.1, 0.1-0.15, 0.15-0.2, and 0.2-0.25 Hz. Therefore, the current study established a progressive self-other transposition group intervention to specifically and systematically improve autistic children's self-other transposition abilities. The transposition test with a three mountains test, an unexpected location test, and a deception test was used to directly measure autistic children's transposition abilities. The Interpersonal Responsiveness Index Empathy Questionnaire with perspective-taking and fantasy subscales (IRI-T) was used to indirectly measure autistic children's transposition abilities. The Autism Treatment Evaluation Checklist (ATEC) was used to measure autistic children's autism symptoms. The experiment was designed with two (intervention: experimental group vs. control group) independent variables and two (test time: pretest vs. posttest or tracking test) × three (test: transposition test vs. IRI-T test vs. ATEC test) dependent variables. Furthermore, it used eyes-closed resting-state functional magnetic resonance imaging to investigate and compare the relevant maternal mALFFs and average energy rank and energy rank variability of mAFFs of autistic children's transposition abilities, autism symptoms, and intervention effects. The results showed the following: (1) There were many improvements (pretest vs. posttest or tracking test) greater than chance 0 in the experimental group, such as the three mountains, lie, transposition, PT, IRI-T, PT tracking, cognition, behavior, ATEC, language tracking, cognition tracking, behavior tracking, and ATEC tracking improvements. However, there was no improvement greater than chance 0 in the control group. (2) The maternal mALFFs and maternal average energy rank and energy rank variability of mAFFs could predict the autistic children's transposition abilities, autism symptoms, and intervention effects with some overlap and some difference in maternal self-other distinction, sensorimotor, visual, facial expression recognition, language, memory and emotion, and self-consciousness networks. These results indicated that the progressive self-other transposition group intervention successfully improved autistic children's transposition abilities and reduced their autism symptoms; the intervention effects could be applied to daily life and last up to a month. The maternal mALFFs, average energy rank, and energy rank variability of mAFFs were three effective neural indictors of autistic children's transposition abilities, autism symptoms, and intervention effects, and the average energy rank and energy rank variability of mAFFs were two new neural indictors established in the current study. The maternal neural markers of the progressive self-other transposition group intervention effects for autistic children were found in part.

9.
Int J Med Sci ; 20(6): 810-817, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37213666

RESUMO

Interferon gamma (IFNγ) is a cytokine implicated in the pathogenesis of autoimmune diseases. SAM and HD domain-containing protein 1 (SAMHD1) is an IFNγ-inducible protein that modulates cellular dNTP levels. Mutations in the human SAMHD1 gene cause Aicardi-Goutières (AG) syndrome, an autoimmune disease sharing similar clinical features with systemic lupus erythematosus (SLE). Klotho is an anti-inflammatory protein which suppresses aging through multiple mechanisms. Implication of Klotho in autoimmune response is identified in rheumatologic diseases such as SLE. Little information exists regarding the effect of Klotho in lupus nephritis, one of the prevalent symptoms of SLE. The present study verified the effect of IFNγ on SAMHD1 and Klotho expression in MES-13 glomerular mesangial cells, a special cell type in glomerulus that is critically involved in lupus nephritis. IFNγ upregulated SAMHD1 expression in MES-13 cells through the Janus kinase-signal transducer and activator of transcription 1 (JAK-STAT1) and the nuclear factor kappa B (NFκB) signaling pathways. IFNγ decreased Klotho protein expression in MES-13 cells. Treatment of MES-13 cells with recombinant Klotho protein inhibited SAMHD1 expression by blocking IFNγ-induced NFκB nuclear translocation, but showed no effect on JAK-STAT1 signaling. Collectively, our findings support the protective role of Klotho in attenuating lupus nephritis through the inhibition of IFNγ-induced SAMHD1 expression and IFNγ downstream signaling in MES-13 cells.


Assuntos
Nefrite Lúpica , NF-kappa B , Humanos , Células Cultivadas , Interferon gama/metabolismo , Nefrite Lúpica/genética , Células Mesangiais/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , Proteína 1 com Domínio SAM e Domínio HD/genética , Proteína 1 com Domínio SAM e Domínio HD/metabolismo , Proteína 1 com Domínio SAM e Domínio HD/farmacologia , Receptor de Interferon gama
10.
Phys Rev E ; 106(3-2): 035207, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36266826

RESUMO

Low-temperature gaseous plasmas exhibit great potential in designing tunable and reconfigurable electromagnetic devices. In this paper, based on an overdense-underdense core-shell plasma structure, tunable Kerker-type invisibility for a radiation-enhanced electrically small antenna is achieved, where dominant scattering direction can be mutated between backward and forward while omnidirectional invisibility and signal enhancement are maintained. Moreover, by electromagnetic multipole decompositions, it is shown that the underdense outer plasma with a negative polarizability is able to weaken the strength and modulate the phase of the electric dipolar scattering component (a_{1}), while the magnetic dipolar term (b_{1}) nearly remains unchanged. Consequently, quasi-first and -second Kerker conditions are fulfilled near the cutoff band of a_{1}.

11.
Int Immunopharmacol ; 112: 109251, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36182875

RESUMO

Ulcerative colitis (UC) is a multifactorial, refractory chronic inflammatory disease. The primary factor leading to prolonged ulcerative colitis is the imbalance of the group 3 innate lymphoid cells (ILC3) subgroup resulting in the delayed reconstruction of damaged intestinal barrier. Previous studies show that luteolin had efficacy on UC, however, the potency of luteolin on restoring the balance of NCR-ILC3/NCR+ILC3 to repairing impaired intestinal barrier remains unclear. In this study, to investigate the potential mechanism of luteolin on ILC3 subgroup, we first evidenced that luteolin could promote transformation NCR-MNK3 to NCR+MNK3 in vitro. Then, a UC model was established in C57BL/6J mice to assess the efficacy of luteolin in restoring ILC3 subgroup balance and repairing intestinal barrier in chronic UC. Finally, the experiments in vitro validated the potential mechanism of luteolin in regulating ILC3 plasticity. The results showed that luteolin significantly alleviated the symptoms of DSS-induced UC in mice, including preventing body weight loss and decreasing the disease activity index (DAI) and intestinal damages. Additionally, luteolin increased NCR+ILC3 levels, promoted the production of IL-22 and decreased the levels of IL-17a and INF-γ in the intestine, and encourage intestinal barrier function recovery in UC mice by promoting the expression of ZO-1 and Occludin. Experiments in vitro revealed that luteolin facilitated the transformation of NCR-MNK3 to NCR+MNK3 and promoted the secretion of IL-22, which was linked to the Notch pathway. All results revealed that luteolin restored the balance of NCR-ILC3/NCR+ILC3 and contributed to repair of injured intestinal epithelium to alleviate ulcerative colitis.


Assuntos
Colite Ulcerativa , Colite , Camundongos , Animais , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/metabolismo , Interleucina-17/metabolismo , Luteolina/farmacologia , Luteolina/uso terapêutico , Imunidade Inata , Ocludina/metabolismo , Camundongos Endogâmicos C57BL , Linfócitos/metabolismo , Intestinos , Mucosa Intestinal/metabolismo , Sulfato de Dextrana , Colite/induzido quimicamente , Modelos Animais de Doenças
12.
Neural Plast ; 2021: 9938566, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34367273

RESUMO

Background: Parkinson's disease (PD) is a common neurological degenerative disease that cannot be completely cured, although drugs can improve or alleviate its symptoms. Optogenetic technology, which stimulates or inhibits neurons with excellent spatial and temporal resolution, provides a new idea and approach for the precise treatment of Parkinson's disease. However, the neural mechanism of photogenetic regulation remains unclear. Objective: In this paper, we want to study the nonlinear features of EEG signals in the striatum and globus pallidus through optogenetic stimulation of the substantia nigra compact part. Methods: Rotenone was injected stereotactically into the substantia nigra compact area and ventral tegmental area of SD rats to construct rotenone-treated rats. Then, for the optogenetic manipulation, we injected adeno-associated virus expressing channelrhodopsin to stimulate the globus pallidus and the striatum with a 1 mW blue light and collected LFP signals before, during, and after light stimulation. Finally, the collected LFP signals were analyzed by using nonlinear dynamic algorithms. Results: After observing the behavior and brain morphology, 16 models were finally determined to be successful. LFP results showed that approximate entropy and fractal dimension of rats in the control group were significantly greater than those in the experimental group after light treatment (p < 0.05). The LFP nonlinear features in the globus pallidus and striatum of rotenone-treated rats showed significant statistical differences before and after light stimulation (p < 0.05). Conclusion: Optogenetic technology can regulate the characteristic value of LFP signals in rotenone-treated rats to a certain extent. Approximate entropy and fractal dimension algorithm can be used as an effective index to study LFP changes in rotenone-treated rats.


Assuntos
Gânglios da Base/efeitos dos fármacos , Potenciais da Membrana/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Optogenética/métodos , Rotenona/farmacologia , Animais , Masculino , Ratos , Ratos Sprague-Dawley , Desacopladores/farmacologia
13.
Trials ; 21(1): 309, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32245480

RESUMO

BACKGROUND: Comprehensive rehabilitation therapy based on traditional Chinese medicine (TCM) has been widely applied in various cancer treatments in China. Thus far, Chinese herbal medicine (CHM) has been shown effective in reducing the adverse effects of chemotherapy and improving the quality of life (QoL) during chemotherapy. The purpose of the present study is to compare the effects of CHM plus Liu Zi Jue (LZJ) exercises with CHM plus rehabilitation education and with placebo plus rehabilitation education in patients who have undergone complete resection for nonsmall-cell lung cancer (NSCLC) followed by postoperative adjuvant chemotherapy. METHODS AND DESIGN: A multicenter, randomized clinical trial will be performed with 354 stage Ib-IIIa NSCLC patients in five centers in China. Patients satisfying the inclusion criteria will be randomly divided into three groups according to a 1:1:1 ratio: intervention group A (IGA), intervention group B (IGB), and control group (CG). Each group will receive adjuvant platinum-based doublet chemotherapy for a total of four cycles. IGA participants will receive chemotherapy combined with CHM and LZJ exercises, IGB participants will receive chemotherapy combined with CHM and rehabilitation education, and CG participants will receive chemotherapy combined with placebo and rehabilitation education. The herbal treatment patients will be given granules daily and LZJ exercises will be performed four times per week during chemotherapy. The primary outcome is QoL, which will be assessed with the European Organization for Research and Treatment of Cancer (EORTC)-QLQ-C43 scale in each cycle. The secondary outcomes include the 2-year disease-free survival rate, disease-free survival, TCM symptoms, tumor markers, safety, and adverse events. After treatment, the patients will be followed up every 3 months within 2 years and every 6 months after 2 years until disease recurrence and/or metastasis. DISCUSSION: Our previous study reported that CHM in combination with chemotherapy could lower the overall incidence of adverse events but increased digestive and gastrointestinal side effects compared with chemotherapy alone in postoperative NSCLC patients. This study will lay a foundation for the effectiveness of chemotherapy with or without a comprehensive rehabilitation program for QoL in patients with postoperative NSCLC. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03372694. Retrospectively registered on 17 December 2018.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/reabilitação , Medicamentos de Ervas Chinesas/uso terapêutico , Terapia por Exercício/educação , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/reabilitação , Antineoplásicos Fitogênicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica , Biomarcadores Tumorais , Quimioterapia Adjuvante , China , Ensaios Clínicos Fase III como Assunto , Intervalo Livre de Doença , Humanos , Estudos Multicêntricos como Assunto , Período Pós-Operatório , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto
14.
Biol Proced Online ; 22: 5, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32140080

RESUMO

BACKGROUND: The toxicity and side effects caused by adjuvant chemotherapy (ACT) after radical surgery for lung adenocarcinoma (LAC) lead to early termination frequently. This study was conducted to provide an objective basis for the effect of Chinese herbal medicine formulas (CHMFs) combined with chemotherapy in reducing toxicity and enhancing efficacy of ACT. METHOD: From February 17th, 2012 to March 20th, 2015, 233 patients from 7 hospitals diagnosed with LAC in IB~IIIA stage were randomly assigned into ACT + CHMF group (116 patients) and ACT + placebo group (117 patients). CHMF was taken orally until the end of chemotherapy. Chemotherapy-related toxic, side effects were investigated as the primary outcome. Disease-free survival (DFS) and overall survival (OS) were used as the secondary outcome. RESULTS: At one week following chemotherapy, the incidence of dry mouth, diarrhea and thrombocytopenia significantly decreased in CHMF group (P = 0.017, P = 0.033, P = 0.019, respectively). At two weeks following chemotherapy, fatigue and diarrhea were more obvious in the placebo group (P = 0.028, P = 0.025, respectively). In addition, patients in the CHMF group showed an increase in median DFS from 37.1 to 51.5 months compared with placebo group although there was no statistical significance (P = 0.16). In the stage IB subgroup, the CHMF group had a significantly better DFS (HR (95% CI) = 0.53 (0.28-0.99), P = 0.046). There was no significant difference in OS between the groups (P = 0.72). CONCLUSION: For patients with LAC, ACT combined with CHMF after radical surgery can prolong the DFS time especially in the early stage, and reduces the chemotherapy-related toxic and side effects. TRIAL REGISTRATION: NCT01441752. Registered 14 July, 2011.

15.
Org Lett ; 22(5): 2022-2025, 2020 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-32096647

RESUMO

The first total synthesis of Gardneria oxindole alkaloid (-)-gardmultimine A has been achieved in 19 steps from d-tryptophan in a fully stereocontrolled manner. This synthesis features (1) an Ir-catalyzed regioselective C-H borylation/oxidation sequence to introduce the C12 methoxyl group, (2) a stereocontrolled oxidative rearrangement of indole to construct the spirooxindole motif, and (3) an Au(I)-catalyzed transannular Conia-ene-type 6-exo-dig cyclization to establish the azabicyclo[2.2.2]octane skeleton and the exocyclic E-alkene with exclusive stereoselectivity.


Assuntos
Triptofano/química , Catálise , Ciclização , Estrutura Molecular , Oxirredução
16.
J Org Chem ; 85(5): 3954-3962, 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-31994398

RESUMO

A strategy for the synthesis of cis-hydrocarbazole with a C3 quaternary carbon center has been developed through nickel/Lewis acid dual-catalyzed arylcyanation. A wide array of cis-hydrocarbazoles was accessed with high diastereoselectivities and atom economies in a good yield. The rich chemistry of the installed nitrile group was demonstrated in the preparation of tryptamine- and tryptophol-derived cis-hydrocarbazoles.

17.
Angew Chem Int Ed Engl ; 59(10): 3966-3970, 2020 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-31898399

RESUMO

The first total synthesis of the Euphorbia diterpenoid pepluanol B in both racemic and enantioenriched form involves 20 steps from a known bicyclic diol. This synthesis features an unprecedented bromo-epoxidation to control the eight-membered-ring conformation. In addition, salient reactions for the construction of the tetracyclic backbone include a sterically challenging aldol reaction to establish the quaternary center, a ring closing metathesis (RCM) to forge the eight-membered ring, and a diastereoselective cyclopropanation to assemble the embedded cyclopropane motif.


Assuntos
Compostos Bicíclicos com Pontes/química , Ciclopropanos/química , Diterpenos/síntese química , Ciclização , Diterpenos/química , Conformação Molecular , Estereoisomerismo
18.
Nat Mater ; 18(12): 1321-1326, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31591530

RESUMO

Alternative technologies are required in order to meet a worldwide demand for clean non-polluting energy sources. Thermoelectric generators, which generate electricity from heat in a compact and reliable manner, are potential devices for waste heat recovery. However, thermoelectric performance, as encapsulated by the figure of merit ZT, has remained at around 1.0 at room temperature, which has limited practical applications. Here, we study the effects of pressure on ZT in Cr-doped PbSe, which has a maximum ZT of less than 1.0 at a temperature of about 700 K. By applying external pressure using a diamond anvil cell, we obtained a room-temperature ZT value of about 1.7. From thermoelectric, magnetoresistance and Raman measurements, as well as density functional theory calculations, a pressure-driven topological phase transition is found to enable this enhancement. Experiments also support the appearance of a topological crystalline insulator after the transition. These findings point to the possibility of using compression to increase not just ZT in existing thermoelectric materials, but also the possibility of realizing topological crystalline insulators.

19.
Bioorg Med Chem ; 27(21): 115092, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31521460

RESUMO

Phenylpyrazole insecticides are successful for crop protection and public hygiene by blocking gamma-aminobutyric acid (GABA)-gated chloride channels and glutamate-gated chloride (GluCl) channels. A series of novel phenylpyrazoles containing arylimine or 1-methoxyaryl groups were designed and synthesized. The addition reaction of methanol to the imines 1-11 was investigated and the cayno addition products 13-15 were obtained. The compounds 1-15 were confirmed by 1H NMR and elemental analysis. The results of bioassay indicated that some compounds exhibited comparable bioactivity to fipronil against a broad spectrum of insects such as bean aphid (Aphis craccivora), mosquito (Culex pipiens pallens), diamondback moth (Plutella xylostella) and Oriental armyworm (Mythimna separata). Especially, the foliar contact activity against bean aphid of compound 7 at 10 µg mL-1 was 68%, the larvacidal activity against mosquito of compounds 5, 13 and 15 at 0.0025 µg mL-1 was 100%, the larvacidal activity against diamondback moth of compounds 9 and 11 at 0.05 µg mL-1 was 100%, the larvacidal activity against Oriental armyworm of compound 9 at 1 µg mL-1 was 100%. The 3-cayno moiety on pyrazole ring was essential for the high insecticidal activities against bean aphid, diamondback moth and Oriental armyworm, while the 3-carbimidate moiety on pyrazole ring was crucial to the excellent high insecticidal activities against mosquito.


Assuntos
Iminas/toxicidade , Inseticidas/toxicidade , Pirazóis/toxicidade , Animais , Desenho de Fármacos , Iminas/síntese química , Insetos/efeitos dos fármacos , Inseticidas/síntese química , Larva/efeitos dos fármacos , Estrutura Molecular , Pirazóis/síntese química , Relação Estrutura-Atividade
20.
Front Pharmacol ; 10: 732, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31333456

RESUMO

Background: To determine the clinical activity and safety of Chinese herbal medicine (CHM) combined with epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKI) in patients with advanced pulmonary adenocarcinoma (ADC) and the ability of CHM combined with EGFR-TKI to activate EGFR mutations. Methods: Three hundred and fifty-four patients were randomly assigned to EGFR-TKI (erlotinib 150 mg/d, gefitinib 250 mg/d, or icotinib 125 mg tid/d) plus CHM (TKI+CHM, N = 185) or EGFR-TKI plus placebo (TKI+placebo, N = 169). Progression-free survival (PFS) was the primary end point; the secondary end points were overall survival (OS), objective response rate (ORR), disease control rate (DCR), quality of life [Functional Assessment of Cancer Therapy-Lung (FACT-L) and Lung Cancer Symptom Scale (LCSS)], and safety. Results: The median PFS was significantly longer for the TKI+CHM group (13.50 months; 95% CI, 11.20-16.46 months) than with the EGFR-TKI group (10.94 months; 95% CI, 8.97-12.45 months; hazard ratio, 0.68; 95% CI, 0.51-0.90; P = 0.0064). The subgroup analyses favored TKI+CHM as a first-line treatment (15.97 vs. 10.97 months, P = 0.0447) rather than as a second-line treatment (11.43 vs. 9.23 months, P = 0.0530). Patients with exon 19 deletion had a significantly longer PFS than with 21 L858R. The addition of CHM to TKI significantly improved the ORR (64.32% vs. 52.66%, P = 0.026) and QoL. Drug-related grade 1-2 adverse events were less common with TKI+CHM. Conclusions: TKI+CHM improved PFS when compared with TKI alone in patients with EGFR mutation-positive advanced non-small-cell lung cancer (NSCLC). Clinical Trial Registration: www.ClinicalTrials.gov, identifier NCT01745302.

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