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1.
Nat Prod Res ; : 1-7, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34822252

RESUMO

Phytochemical investigation of the fruits of Crataegus pinnatifida Bunge led to the isolation of four pairs enantiomeric benzofuran lignans (1a/1b-4a/4b) including four undescribed compounds (1a, 2b, 3b and 4b). Their structures were determined by extensive spectroscopic methods and the absolute configurations were further determined by the comparison of experimental and calculated ECD spectra. All the enantiomeric lignans were evaluated for their inhibitory activities to tyrosinase. Among them, compound 4a showed moderate inhibition activity (IC50 = 0.54 mM).

3.
J Org Chem ; 86(21): 15298-15306, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34612634

RESUMO

Daphnenoids A-C (1-3), three unusual sesquiterpenes with distinctive ring skeletons, together with a biogenetically related daphnenoid D (4) were obtained from the herb of Daphne penicillata by molecular networking strategies. Daphnenoid A (1) possesses a unique caged tetracyclo [5.3.2.01,6.04,11] dodecane scaffold by unexpected cyclizations of C-1/C-11 and C-2/C-14. Daphnenoids B and C (2 and 3) were the first discovered natural sesquiterpenes with unique 5/5 spirocyclic systems in nature. Their structures were determined by NMR spectroscopic analysis, computer-assisted structure elucidation methods, quantum chemical calculations, and X-ray diffraction. A hypothetical biogenetic pathway begins with typical guaiane sesquiterpene (a), including a key intermediate (4) was proposed. Daphnenoids B and C (2 and 3) exhibited potential inhibitory activities on the production of NO against LPS-induced BV2 microglial cells.

5.
J Asian Nat Prod Res ; : 1-10, 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34585635

RESUMO

Ten compounds (1-10) including four new compounds (1-4) and six known compounds (5-10) were isolated from Solanum nigrum. Their structures were elucidated on the basis of spectroscopic data, gauge-including atomic orbital (GIAO) calculation of NMR data, DP4+ probability analysis and comparison of their experimental and calculated electronic circular dichroism (ECD) spectral data. All the isolated compounds were tested for their neuroprotective activities against H2O2-induced damage in SH-SY5Y cells. Among them, compounds 1, 5 and 7 displayed moderate neuroprotective effects.

6.
Ann Surg Oncol ; 2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34591226

RESUMO

BACKGROUND: Hepatectomy with tumor thrombectomy is the preferred treatment option for hepatocellular carcinoma (HCC) patients with bile duct tumor thrombus (BDTT); however, the impact of BDTT on their prognosis is unclear. OBJECTIVE: We aimed to investigate the long-term surgical outcomes of HCC patients with BDTT. METHODS: The data of HCC patients with and without BDTT who underwent hepatectomy were retrospectively reviewed and the long-term outcomes were compared. For propensity score matching (PSM) analysis, patients were matched in a 1:1 ratio. Subgroup analysis was conducted according to the American Joint Committee on Cancer (AJCC) staging system. RESULTS: Before PSM, HCC patients with BDTT had more advanced tumor stages and adverse clinicopathological features. Recurrence-free survival (RFS) and overall survival (OS) were significantly higher in the non-BDTT group before PSM (RFS, p < 0.001; OS, p < 0.001), while after PSM, the BDTT group had significantly poorer RFS (p = 0.025). There was no difference in OS between the groups (p = 0.588). Subgroup analysis showed that RFS and OS in AJCC stage I-II patients were significantly poorer in the BDTT group; no differences were found in the AJCC stage III group before or after PSM. When the presence of BDTT was recommended to increase the AJCC staging system by one stage in AJCC stage I-II patients, the predictive ability for RFS and OS was higher. CONCLUSIONS: BDTT was associated with significantly poorer long-term surgical outcomes in AJCC stage I-II patients. A modified AJCC staging system including BDTT status in stage I-II might have a better prognostic ability.

7.
Chin J Nat Med ; 19(9): 680-685, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34561079

RESUMO

Seven alkaloids including five undescribed ones (1a/1b, 2, 3 and 5) were obtained from the leaves of Isatis indigotica Fortune. Their structures were established by extensive spectroscopic analyses. The absolute configurations of compounds 1a, 1b, 3 and 5 were determined by comparison of the experimental and calculated electronic circular dichroism (ECD) spectra. Subsequently, the neuroprotective effects of all the isolates against H2O2-induced injury in SH-SY5Y cells were evaluated in vitro by MTT assay. Moreover, Annexin V-FITC/PI double staining was performed, while the activities of antioxidant enzymes (SOD, CAT and GSH-Px) for compounds 1a and 1b were measured.


Assuntos
Alcaloides , Isatis , Fármacos Neuroprotetores , Alcaloides/farmacologia , Peróxido de Hidrogênio/toxicidade , Estrutura Molecular , Fármacos Neuroprotetores/farmacologia , Folhas de Planta
8.
Org Lett ; 23(18): 7231-7235, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34436914

RESUMO

Eleucanainones A and B are two structurally complex naphthoquinone-derived dimers whose structure identification is difficult. Large yellow fragments of the preliminary CASE (computer-assisted structure elucidation) analysis revealed that the original structures might be questionable. Structural revisions of the two compounds were proposed on the basis of NMR analysis, CASE methods, conformation analysis, and DFT (density functional theory) NMR calculations with a custom DP4+ analysis. In addition, a polyketide-folded biosynthetic pathway of the two revised structures was proposed.

9.
Eur J Med Chem ; 218: 113395, 2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-33838584

RESUMO

A series of flavonoid-triazolyl hybrids were synthesized and evaluated as novel inhibitors of hepatitis C virus (HCV). The results of anti-HCV activity assays showed that most of the synthesized derivatives at a concentration of 100 µg/mL inhibited the generation of progeny virus. Among these derivatives, 10m and 10r exhibited the most potent anti-HCV activity and inhibited the production of HCV in a dose-dependent manner. Interestingly, 10m and 10r had no significant inhibitory effect on viral translation or replication. Additional action mechanism studies revealed that the most potent compounds, 10m and 10r, significantly inhibited viral entry to 34.0% and 52.0%, respectively, at 10 µM. These results suggest further effective application of 10m and 10r as potential HCV preventive agents.


Assuntos
Antivirais/farmacologia , Flavonoides/farmacologia , Hepacivirus/efeitos dos fármacos , Triazóis/farmacologia , Antivirais/síntese química , Antivirais/química , Relação Dose-Resposta a Droga , Flavonoides/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade , Triazóis/química , Replicação Viral/efeitos dos fármacos
10.
Ann Surg Oncol ; 28(12): 7686-7695, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33929619

RESUMO

BACKGROUND: Anatomic resection (AR) of the liver is generally recommended in hepatocellular carcinoma (HCC) patients. However, the benefits of AR and nonanatomic resection (NAR) in HCC patients with bile duct tumor thrombus (BDTT) are unknown. This study aimed to compare long-term outcomes of AR and NAR in HCC patients with BDTT after curative resection. PATIENTS AND METHODS: A total of 175 consecutive HCC patients with BDTT after curative resection between April 2009 and December 2017 were included. One-to-one propensity score matching (PSM) was performed to minimize the influence of potential confounders. Recurrence-free survival (RFS) and overall survival (OS) were compared between the cohorts. RESULTS: After PSM, 120 patients were analyzed. The AR group had better RFS than the NAR group (P = 0.010). Even though there was no statistically significant difference in OS (P = 0.140, power = 0.33), the 3- and 5-year OS rates in the AR group (52.4% and 44.2%, respectively) were obviously higher than those in the NAR group (35.4% and 30.4%, respectively). When patients were further stratified according to tumor size, better RFS and OS were observed in patients with small (≤ 5 cm) tumors after AR (P < 0.001 and P = 0.004, respectively). Multivariate analysis identified AR (P = 0.024) as an independent favorable prognostic factor for RFS in HCC patients with BDTT. CONCLUSIONS: AR is recommended for HCC patients with BDTT, especially in patients with small (≤ 5 cm) tumors.


Assuntos
Neoplasias dos Ductos Biliares , Carcinoma Hepatocelular , Neoplasias Hepáticas , Trombose , Neoplasias dos Ductos Biliares/cirurgia , Carcinoma Hepatocelular/cirurgia , Hepatectomia , Humanos , Neoplasias Hepáticas/cirurgia , Pontuação de Propensão , Estudos Retrospectivos , Trombose/etiologia , Trombose/cirurgia
11.
Phytochemistry ; 187: 112769, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33887559

RESUMO

Quassinoids, originating from the oxidative degradation of tetracyclic tirucallane triterpene, are a diverse class of secondary metabolites identifying from nature mostly in Simaroubaceae family. The crucial pharmacological activities and structural complexity of quassinoids have long fascinated scientists due to their medicinal uses, infamous toxicity, and unique biosynthesis. In the past few decades, 482 quassinoids, assigned to 6 skeletons, have been isolated and identified from plants. The names, classes, molecular formula, and plant sources of these secondary metabolites are collated here. This review will be a detailed update of the naturally occurring quassinoids reported from the plant kingdom, providing an in-depth discussion of their diversity, antitumor activities, structure-activity relationship.


Assuntos
Quassinas , Simaroubaceae , Extratos Vegetais , Plantas , Quassinas/farmacologia , Relação Estrutura-Atividade
12.
BMC Cancer ; 21(1): 272, 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33711965

RESUMO

BACKGROUND: Bile duct invasion is a relatively rare event and is not well characterised in hepatocellular carcinoma (HCC). It remains very difficult to diagnose HCC with bile duct tumour thrombus (BDTT) before surgery. Increasing evidence has revealed that inflammation plays a critical role in tumorigenesis. This study aimed to develop nomograms based on systemic and hepatic inflammation markers to predict microscopic BDTT (micro-BDTT) before surgery in HCC. METHODS: A total of 723 HCC patients who underwent hepatectomy as initial therapy between January 2012 and June 2020 were included in the study. Logistic regression analysis was used to identify independent risk factors for micro-BDTT. The nomograms were constructed using significant predictors, including α-fetoprotein (AFP), alkaline phosphatase (ALP), direct bilirubin (DB), prognostic nutritional index (PNI), and γ-glutamyl transferase (γ-GT)/alanine aminotransferase (ALT). The prediction accuracies of the nomograms were evaluated using the area under the receiver operating characteristic (ROC) curve. RESULTS: AFP, ALP, DB, PNI, and γ-GT/ALT were independent risk factors for predicting micro-BDTT (P = 0.036, P = 0.004, P = 0.013, P = 0.012, and P = 0.006, respectively), which were assembled into the nomograms. The area under the ROC curve of the nomograms combining PNI and γ-GT/ALT for predicting micro-BDTT was 0.804 (95% confidence interval [CI]: 0.730-0.878). The sensitivity and specificity values when used in predicting micro-BDTT before surgery were 0.739 (95% CI: 0.612-0.866) and 0.781 (95% CI: 0.750-0.813), respectively. CONCLUSIONS: The nomogram based on combining systemic and hepatic inflammation markers is suitable for predicting micro-BDTT before surgery in HCC patients, leading to a rational therapeutic choice for HCC.


Assuntos
Carcinoma Hepatocelular/complicações , Colestase Intra-Hepática/epidemiologia , Icterícia Obstrutiva/epidemiologia , Neoplasias Hepáticas/complicações , Nomogramas , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Colestase Intra-Hepática/etiologia , Colestase Intra-Hepática/patologia , Colestase Intra-Hepática/cirurgia , Feminino , Hepatectomia , Humanos , Icterícia Obstrutiva/etiologia , Icterícia Obstrutiva/patologia , Icterícia Obstrutiva/cirurgia , Fígado/patologia , Fígado/cirurgia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Estudos Retrospectivos , Medição de Risco/métodos
13.
World J Clin Cases ; 9(8): 1803-1813, 2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33748229

RESUMO

BACKGROUND: Laparoscopic cholecystectomy (LC) combined with laparoscopic common bile duct (CBD) exploration (LCBDE) is one of the main treatments for choledocholithiasis with CBD diameter of larger than 10 mm. However, for patients with small CBD (CBD diameter ≤ 8 mm), endoscopic sphincterotomy remains the preferred treatment at present, but it also has some drawbacks associated with a series of complications, such as pancreatitis, hemorrhage, cholangitis, and duodenal perforation. To date, few studies have been reported that support the feasibility and safety of LCBDE for choledocholithiasis with small CBD. AIM: To investigate the feasibility and safety of LCBDE for choledocholithiasis with small CBD. METHODS: A total of 257 patients without acute cholangitis who underwent LC + LCBDE for cholecystolithiasis from January 2013 to December 2018 in one institution were reviewed. The clinical data were retrospectively collected and analyzed. According to whether the diameter of CBD was larger than 8 mm, 257 patients were divided into large CBD group (n = 146) and small CBD group (n = 111). Propensity score matching (1:1) was performed to adjust for clinical differences. The demographics, intraoperative data, short-term outcomes, and long-term follow-up outcomes for the patients were recorded and compared. RESULTS: In total, 257 patients who underwent successful LC + LCBDE were enrolled in the study, 146 had large CBD and 111 had small CBD. The median follow-up period was 39 (14-86) mo. For small CBD patients, the median CBD diameter was 0.6 cm (0.2-2.0 cm), the mean operating time was 107.2 ± 28.3 min, and the postoperative bile leak rate, rate of residual CBD stones (CBDS), CBDS recurrence rate, and CBD stenosis rate were 5.41% (6/111), 3.60% (4/111), 1.80% (2/111), and 0% (0/111), respectively; the mean postoperative hospital stay was 7.4 ± 3.6 d. For large CBD patients, the median common bile duct diameter was 1.0 cm (0.3-3.0 cm), the mean operating time was 115.7 ± 32.0 min, and the postoperative bile leak rate, rate of residual CBDS, CBDS recurrence rate, and CBD stenosis rate were 5.41% (9/146), 1.37% (2/146), 6.85% (10/146), and 0% (0/146), respectively; the mean postoperative hospital stay was 7.7 ± 2.7 d. After propensity score matching, 184 patients remained, and all preoperative covariates except diameter of CBD stones were balanced. Postoperative bile leak occurred in 11 patients overall (5.98%), and no difference was found between the small CBD group (4.35%, 4/92) and the large CBD group (7.61%, 7/92). The incidence of CBDS recurrence did not differ significantly between the small CBD group (2.17%, 2/92) and the large CBD group (6.52%, 6/92). CONCLUSION: LC + LCBDE is safe and feasible for choledocholithiasis patients with small CBD and did not increase the postoperative bile leak rate compared with chole-docholithiasis patients with large CBD.

14.
Phytochemistry ; 184: 112675, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33548770

RESUMO

Seven undescribed tirucallane-type triterpenoids, kumunorquassins A‒E and kumuquassins K and L, along with nine known analogues, have been isolated from the leaves of Picrasma quassioides (D. Don) Benn. Their structures and absolute configurations were elucidated based on comprehensive spectroscopic analyses, single-crystal X-ray diffraction analysis and electronic circular dichroism (ECD). The absolute configuration of cornusalterin J was unequivocally determined by X-ray diffraction based on its p-bromobenzoate derivative. A brief approach was presented in our study, which could rapidly and conveniently determine the relative and absolute configurations of OCH3-23 of kumuquassin L and cornusalterins J, H and G depending on the chemical shift differences (Δδ) of C-24 and C-25 and the chemical shifts of C-23, H-23 and H-24. In addition, the cytotoxicities of these compounds against two human tumour cell lines (HepG2 and Hep3B) were evaluated.


Assuntos
Picrasma , Triterpenos , Estrutura Molecular , Folhas de Planta , Triterpenos/farmacologia
15.
J Nat Prod ; 84(1): 20-25, 2021 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-33415978

RESUMO

The structural elucidation of chiral molecules with more than one stereocenter is usually a tricky problem. In this paper, efficient 1H NMR spectroscopic approaches for assigning the erythro and threo configurations of 1-oxygenated 1,2-diarylpropan-3-ols were developed. By analysis of the chemical shift differences of diastereotopic methylene H2-3 (Δδ3) in CDCl3 or the chemical shift differences of H-1 and H-2 (Δδ1,2) in methanol-d4, deuterated dimethyl sulfoxide, and acetone-d6, the configurations of 1-oxygenated 1,2-diarylpropan-3-ols can be rapidly and conveniently determined.


Assuntos
1-Propanol/química , Dimetil Sulfóxido/química , Oxigênio/química , Espectroscopia de Ressonância Magnética/métodos , Estereoisomerismo
16.
Phytochemistry ; 183: 112628, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33412403

RESUMO

Nine undescribed guaiane-type sesquiterpenoids stelleraterpenoids A‒I, along with seven reported congeners, were isolated and identified from the 70% EtOH extract of the roots of Stellera chamaejasme L. Their chemical structures were elucidated on the basis of various spectral data. The relative configurations were determined by their NOESY spectra and comparison between their experimental and calculated NMR data. The absolute configurations were established by the comparison between the experimental and calculated ECD spectra and further by X-ray single-crystal diffraction analysis. The neuroprotective effects of these compounds on the H2O2-induced damage in human neuroblastoma SH-SY5Y cells were evaluated. Stelleraguaianone B exhibited the better activity with 71.62% cell viability compared to the positive control Trolox (65.05%) at 12.5 µM, which might be achieved by inhibiting the apoptosis of SH-SY5Y cells based on an annexin V-FITC/PI staining experiment.


Assuntos
Fármacos Neuroprotetores , Sesquiterpenos , Thymelaeaceae , Peróxido de Hidrogênio , Estrutura Molecular , Fármacos Neuroprotetores/farmacologia , Sesquiterpenos/farmacologia , Sesquiterpenos de Guaiano
17.
J Asian Nat Prod Res ; 23(3): 217-227, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32102545

RESUMO

Four new alkaloids (1-4) and one known alkaloid were isolated from the stems of Picrasma quassioides. The structures of these isolated compounds were elucidated by spectroscopic analyses, a combination of computer-assisted structure elucidation software (ACD/Structure Elucidator) and gauge-including atomic orbital (GIAO) calculation of 1 D NMR data. All compounds were evaluated for their cytotoxic activities against hepatocellular carcinoma HepG2 and Hep3B cells. However, they did not show obvious inhibitory activities.[Figure: see text].


Assuntos
Alcaloides , Neoplasias Hepáticas , Picrasma , Alcaloides/farmacologia , Computadores , Humanos , Estrutura Molecular
18.
J Asian Nat Prod Res ; 23(2): 103-109, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32024382

RESUMO

Two new benzoic acid derivatives (1-2), together with four known compounds (3-6) have been isolated from the n-BuOH soluble fraction of ethanolic extract from Ailanthus altissima. The gross structures of the new compounds were deduced by detailed spectroscopic analysis including HRESIMS and 1D/2D NMR spectroscopy. The stereochemistry of 1 was determined by modified Mosher's method. All compounds were evaluated for their neuroprotective effects against H2O2-induced oxidative stress in human neuroblastoma SH-SY5Y cells and none of them displayed obvious neuroprotective activities. [Formula: see text].


Assuntos
Ailanthus , Ácido Benzoico , Peróxido de Hidrogênio/farmacologia , Estrutura Molecular , Extratos Vegetais
19.
J Asian Nat Prod Res ; 23(8): 738-744, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32627578

RESUMO

Three new compounds, crotalariapallins A-C (1-3), were isolated from the 95% EtOH extract of the seeds of Crotalaria pallida. Their structures were established based on extensive spectroscopic methods, including HRESIMS, UV, 1D and 2D NMR. All compounds were evaluated for their inhibitory activities to tyrosinase. These compounds showed different degrees of inhibitory activities, among them, compound 3 exhibited the strongest inhibition activity (IC50 = 0.42 mM).


Assuntos
Crotalaria , Estrutura Molecular , Monofenol Mono-Oxigenase , Sementes
20.
J Asian Nat Prod Res ; 23(6): 609-614, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32644854

RESUMO

Previous work has shown that the lignans from the twigs and leaves of Archidendron clypearia (Jack) I.C.N. possess anti-ß-amyloid aggregation activity. Here we report a new dilignan, archidendronin A (1), along with one known sesquilignan (2). Their structures were determined by extensive spectroscopic methods, including UV, HRESIMS, 1 D and 2 D NMR data. The inhibitory activity on Aß1-42 aggregation was screened by ThT assay with curcumin as the positive control, and compounds 1 and 2 showed inhibition rate of 60.0% and 64.4% at 20 µM, respectively.[Formula: see text].


Assuntos
Fabaceae , Lignanas , Estrutura Molecular , Extratos Vegetais , Folhas de Planta
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