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1.
J Org Chem ; 88(15): 10586-10598, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37449800

RESUMO

Spiro[indoline-3,3'-pyrrolidine] and spiro[indoline-3,3'-piperidine] derivatives were synthesized in a substitution-controlled manner under the catalysis of cationic gold(I) species in the presence of Hantzsch ester (HEH). The optimal reaction condition was determined by screening, and the functional group tolerances of these two pathways were examined by readily synthetic substrates. The endo and exo selectivities of these cyclizations were elucidated by density functional theory calculations, and a plausible mechanism for these transformations was proposed.

2.
J Org Chem ; 88(11): 7179-7187, 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37172220

RESUMO

Six 8-oxoprotoberberines were synthesized collectively in four steps with acceptable yields (14-19%), of which the products 8-oxopalmatine, 8-oxopseudopalmatine, 8-oxoberberine, and 8-oxopseudoberberine come from nature. The synthetic route was featured with the In(OTf)3-catalyzed cyclization and Heck coupling. Moreover, the syntheses of the natural products berberine, canadine, and iambertine were achieved via various reductions from 8-oxoberberine, which provided a concise approach to the syntheses of this kind of alkaloids.

3.
Front Cell Infect Microbiol ; 13: 1289909, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38235492

RESUMO

Background: Sarcopenia can lead to significant personal, social, and economic burdens. The diagnosis of sarcopenia heavily relies on the identification of Low Skeletal Muscle Mass (LSMM), which is an independent predictor of frailty, disability, and increased risk of death among seniors. Women have physiologically lower levels of skeletal muscle mass than men, and female sarcopenia appears to be more influenced by menopause. They also tend to have higher body fat levels than man, which increases the risk of sarcopenia obesity. On another front, it's also recognized that humans are largely prone to Helicobacter pylori (H. pylori) infection, with global prevalence rates often surpassing 50%. Nevertheless, the interconnection between H. pylori infection and LSMM remains relatively unexplored. Hence, our study specifically targeted women as the research population and sought to explore several risk factors for LSMM. Additionally, we delved into the potential correlation between LSMM and H. pylori infection in women, hoping to gain insights into potential preventative measures or treatment options that may enhance the quality of life for women affected by sarcopenia. Methods: We conducted a cross-sectional study among women aged over 18 years undergoing physical examination. We performed 13C-urea breath test (UBT) for diagnosis of H. pylori infection and Bioelectrical impedance analysis (BIA) for the assessment of LSMM. Logistic regression models were used to analyze the associations of H. pylori infection with LSMM. Results: This study enrolled 1984 Chinese women who were undergoing health check-ups. A univariate logistic regression analysis did not reveal a direct correlation between H. pylori infection and LSMM among this female population (OR=1.149, 95% CI 0.904-1.459, p=0.257). Yet, upon dividing the participants into age-based subgroups, an evident link was observed between H. pylori infection and LSMM in women aged 40 or above (OR=1.381, 95%CI 1.032-1.848, p= 0.030). After adjusting for variables including Age, BMI, TP, ALK, Cre, this relationship remained statistically relevant (OR=1.514, 95%CI 1.085-2.113, p= 0.015). Conclusions: Women who are over 40 years old and currently infected with H. pylori have an increased risk of developing LSMM. Therefore, timely treatment for H. pylori eradication is recommended for this group of women to reduce the occurrence of LSMM.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Sarcopenia , Masculino , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Estudos Transversais , Sarcopenia/complicações , Sarcopenia/epidemiologia , Qualidade de Vida , Infecções por Helicobacter/complicações , Infecções por Helicobacter/epidemiologia , Infecções por Helicobacter/diagnóstico , Músculo Esquelético , China/epidemiologia
4.
Beilstein J Org Chem ; 18: 1589-1595, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36483093

RESUMO

The formal total synthesis of macarpine was accomplished by the construction of a naphthol intermediate in Ishikawa's synthetic route with two different synthetic routes. The convergent synthetic strategies feature the utilization of Au(I)-catalyzed cycloisomerizations of a 1,5-enyne and alkynyl ketone substrates, which were prepared by Sonogashira coupling reactions.

5.
Org Lett ; 24(45): 8310-8315, 2022 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-36342358

RESUMO

Collective total syntheses of 10 benzo[c]phenanthridines were achieved on the basis of the construction of rings C and B through sequential transition metal-catalyzed reactions and flexible condition-controlled Mannich reaction via three pots in 25-34% yields, which provided an efficient route to benzo[c]phenanthridines via a pot-economic approach.


Assuntos
Alcaloides , Elementos de Transição , Fenantridinas , Catálise
6.
Org Lett ; 24(37): 6777-6782, 2022 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-36103647

RESUMO

The syntheses of 2,2'-spirobi[indene] derivatives based on a gold(I)-catalyzed tandem strategy involving intramolecular methoxylation/double aldol condensation were achieved. Examination of the scope of this tandem reaction by using a batch of alkynone substrates disclosed that the reaction possessed a good functional group tolerance. A cationic gold(I) catalyst/protonic acid-catalyzed mechanism for this tandem reaction is proposed.


Assuntos
Ouro , Indenos , Aldeídos/química , Catálise , Ouro/química
7.
Br J Neurosurg ; : 1-8, 2022 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-35285360

RESUMO

OBJECTIVE: This study aimed to describe the extended intradural anterior transpetrous approach (ATPA) and its usefulness for the surgical resection of petroclival meningiomas (PCMs) of the cerebellopontine angle (CPA) and/or diaphragma sellae (DS) extension. METHODS: Between January 2017 and December 2019, a total of 22 patients with PCMs extending to the CPA/or DS underwent surgery via extended intradural ATPA by the senior author (Xr.X.). We retrospectively analysed the clinical data, radiological findings, surgical treatment, complications, and outcomes of patients and discussed the operative technique. RESULTS: In 22 patients, the tumours were gross totally removed (Simpson I and II) in 18 patients (81.8%), subtotally (Simpson III) in 3 patients (13.6%), and partially (Simpson IV) in 1 patient (4.5%). One patient died 48 days after the operation, and no recurrence was found in 21 patients during a median follow-up of 26 months. Postoperative complications included in abducens nerve palsy in 12 patients with recovery in 10 patients, facial numbness in 4 patients with recovery in 3 patients, and hemiplegia and oculomotor nerve palsy in 1 patient each with recovery in all patients. The postoperative MRI showed temporal lobe oedema but no clinical symptoms in 3 patients. CONCLUSION: Extended intradural ATPA is an alternative approach for PCMs of the CPA and/or DS extension. The single approach can expose both the sellar region and the posterolateral area of the IAC, which is advantageous for extended intradural ATPA.

8.
J Craniofac Surg ; 32(8): 2692-2694, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34727473

RESUMO

ABSTRACT: The reconstruction of large tissue defects after the resection of brain tumors is challenging for every neurosurgeon. The authors describe the benefits of a skin flap with vascular pedicle in the reconstruction of large tissue defects after the resection of brain tumors. In this retrospective analysis, a skin flap with vascular pedicle reconstruction was used in 5 patients who underwent intracranial tumor resection, accompanied by tissue defects, cerebrospinal fluid leakage and scalp infection. The surgical techniques are described, and the outcomes were discussed. The harvested flaps showed well-vascularized healing of the transplanted skin without partial necrosis in all 5 patients. One patient had cerebrospinal rhinorrhea, which was successfully treated by endoscopic repair. Another patient had cerebrospinal fluid leakage, which was successfully treated by continuous lumbar drainage. A skin flap with vascular pedicle is an effective choice for the reconstruction of large tissue defects after the resection of brain tumors.


Assuntos
Neoplasias Encefálicas , Procedimentos de Cirurgia Plástica , Neoplasias Encefálicas/cirurgia , Vazamento de Líquido Cefalorraquidiano/cirurgia , Humanos , Estudos Retrospectivos , Retalhos Cirúrgicos/cirurgia
9.
Neuropsychiatr Dis Treat ; 16: 1015-1022, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32368063

RESUMO

INTRODUCTION: Cerebral arteriovenous malformation (cAVM) is a disease characterized by the angiogenesis and remodeling of veins. However, whether vascular endothelial cells (ECs) exhibit morphological and functional changes during cAVM remains unclear. This study aimed to investigate the role of ECs in the pathogenesis of cAVM. METHODS: Rat model of cAVM was established by anastomosing the common carotid artery with the external jugular vein. The digital subtraction angiography (DSA), HE, Masson and immunohistochemical staining were performed to evaluate the model. ECs were isolated from AVM rat model or control rats, and characterized by MTT, cell scratch, and tube formation assays. The secretion of vascular endothelial growth factor (VEGF) was detected by ELISA. RESULTS: AVM rat model showed typical pathological characteristics of cAVM. In addition, the proliferation, migration and tube formation abilities of ECs of arterialized vein (AV-ECs) were significantly better than those of ECs of normal vein (NV-ECs). Moreover, the levels of secreted VEGF were significantly higher in AV-ECs than in NV-ECs. CONCLUSION: AV-ECs isolated from AVM rat model showed increased proliferation, migration and angiogenesis and may be potential target for the treatment of cAVM.

10.
Org Biomol Chem ; 16(40): 7361-7374, 2018 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-30124720

RESUMO

A multifaceted gold(i)-catalyzed aromaticity-driven double 6-endo cascade cyclization strategy to synthesize both 12H-benzo[a]xanthen-12-ones and benzo[a]acridin-12(7H)-ones, whose core motifs xanthone and acridone both exist as important scaffolds in an immense number of bioactive compounds, was developed. The scopes of this strategy were examined by using a batch of synthetic 1,3-diphenylprop-2-yn-1-one substrates. To probe the mechanism of this cyclization a control experiment for synthesizing intermediates was performed. Thus, a putative mechanism was determined according to this experiment and previous studies.

11.
Org Lett ; 19(13): 3402-3405, 2017 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-28598637

RESUMO

The cyclization order of the difunctional 1,2-diphenylethynes was precisely tuned under the catalysis of gold by changing the nitrogen substitution of the substrates, leading to the facile preparation of benzo[a]carbazole and indeno[1,2-c]quinoline derivatives. The mechanisms of these domino cyclizations were probed by control experiments, and an insight into the selectivity of the cyclization was gained by density functional theory (DFT) calculations. This research represents a unified and common method to access benzo[a]carbazoles and indeno[1,2-c]quinolines.

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