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1.
Int J Gynecol Cancer ; 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33608452

RESUMO

BACKGROUND: Villoglandular adenocarcinoma is a rare sub-type of cervical adenocarcinoma. OBJECTIVE: To analyze the clinicopathological features and evaluate the prognosis of patients with villoglandular adenocarcinoma of the cervix. METHODS: Patient characteristics, procedure, pathology, and surgical outcomes were retrospectively reviewed in patients with villoglandular adenocarcinoma between November 2006 and June 2019 from multiple centers in China. In order to explore the difference between villoglandular adenocarcinoma and routine adenocarcinoma, patients (FIGO 2009 stage IA1-IB2) who had complete data during the same time period were included. RESULTS: A total of 60 patients with villoglandular adenocarcinoma and 104 with standard adenocarcinoma were included. The median age of the patients with villoglandular adenocarcinoma was 42 years (range 27-68). The most common 2009 FIGO stage was IB1 in 39 (65%) patients with villoglandular adenocarcinoma. A total of 23 patients underwent laparoscopic surgery (two total hysterectomies, 21 radical hysterectomies) and the other 37 patients underwent laparotomy (three total hysterectomies, 34 radical hysterectomies). A total of 56 patients underwent lymphadenectomy and three (5.4%) had positive lymph nodes. Fifteen (25%) patients had one or both ovaries preserved. Seven patients were lost to follow-up. The median follow-up time for the entire group was 50.2 months (range 5.1-154.6). No deaths or recurrences occurred. Excluding six patients with FIGO 2009 stage II, the 5-year disease-free survival of the 47 patients with villoglandular adenocarcinoma with FIGO 2009 stage I for whom there was follow-up, was significantly higher than that of the 104 patients with standard cervical adenocarcinoma (100% vs 92.2%, log-rank p=0.039). However, the 5-year overall survival of the two groups did not differ (100% vs 95.7%, log-rank p=0.11). CONCLUSION: Villoglandular adenocarcinoma has a favorable prognosis. Further studies are needed to provide more details of treatment strategies and prognosis.

2.
J Org Chem ; 86(3): 2135-2157, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33433196

RESUMO

A concise and diastereoselective construction of the ABCD ring system of spirochensilide A is described. The key steps of this synthesis are a semipinacol rearrangement reaction to stereoselectively construct the AB ring system bearing two vicinal quaternary chiral centers and a Co-mediated Pauson-Khand reaction to form the spiro-based bicyclic CD ring system. This chemistry leads to the stereoselective synthesis of 13(R)-demethyl spirochensilide A, paving the way for the first asymmetric total synthesis of (-)-spirochensilide A.

3.
J Org Chem ; 86(3): 2158-2172, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33481592

RESUMO

The final phase of the total synthesis of (-)-spirochensilide A is described. A tungsten-mediated cyclopropene-based Pauson-Khand reaction was developed to form the spiral CD ring system with desired stereochemistry at the C13 quaternary center. Other important steps enabling completion of this synthesis included an intermolecular aldol condensation to link the ABCD core with the EF fragment and a Cu-mediated 1,4-addition to stereoselectively install the C21 stereogenic center. The chemistry developed for this total synthesis of (-)-spirochensilide A (1) will aid the synthesis of polycyclic natural products bearing this unique spiral ring system.

4.
J Am Chem Soc ; 142(46): 19487-19492, 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33152240

RESUMO

A concise chemical synthesis of (+)-haperforin G in 20 steps from commercially available starting materials is achieved with the integration of the Co-catalyzed intramolecular Pauson-Khand reaction for the stereoselective construction of cyclopentanone bearing an all-carbon quaternary stereogenic center at the bridge-head position and the light-initiated photocatalysis for convergent and asymmetric cross-coupling of the unstabilized C(sp3)-radical with an enone. The developed chemistry paves the way to synthesizing structurally diverse analogs of haperforin G (6).

5.
Zootaxa ; 4851(1): zootaxa.4851.1.11, 2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-33056746

RESUMO

Euphorinae (Hymenoptera, Braconidae) is a large subfamily of endoparasitoid wasps with 1,270+ described species worldwide (Yu et al. 2016). In the phylogenetic analysis of Stigenberg et al. (2015) Rilipertus Haeselbarth, 1996 was recovered within the tribe Perilitini Forster,1862 together with several other genera. Rilipertus is morphologically similar to Microctonus Wesmael, 1836 and Perilitus Nees, 1819 by the type of wing venation, structure of propodeum, and shape and structure of first metasomal tergite. However, Rilipertus differs distinctly from them by having shorter and conspicuously broadened ovipositor sheaths and the sculpture of the first tergite is reduced. Six species of Rilipertus are currently known (Yu et al. 2016).


Assuntos
Vespas , Animais , China , Filogenia , Registros , Asas de Animais
6.
Zookeys ; 933: 95-105, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32508490

RESUMO

A new species of the genus Myiocephalus Marshall, 1898, M. cracentis Li, sp. nov. from the Palaearctic (China, Ningxia, Hubei), is described and illustrated. A key to known species of Myiocephalus is provided. Myiocephalus boops (Wesmael, 1835), is a new record for Jilin province (NE China).

7.
J Am Chem Soc ; 142(18): 8116-8121, 2020 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-32286815

RESUMO

An asymmetric total synthesis of (-)-spirochensilide A has been achieved for the first time. The synthesis features a semipinacol rearrangement reaction to stereoselectively construct the two-vicinal quaternary chiral centers at C8 and C10, a tungsten-mediated cyclopropene-based Pauson-Khand reaction to install the C13 quaternary chiral center, and a furan-based oxidative cyclization to stereoselectively form the spiroketal motif.

8.
J Am Chem Soc ; 142(1): 573-580, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31789517

RESUMO

Pre-schisanartanin C belongs to the family of Schisandra nortriterpenoids with potent antihepatitis, antitumor, and anti-HIV activities. This paper presents the enantioselective total synthesis of pre-schisanartanin C (1). An important step in the total synthesis of 1 is gold-catalyzed intramolecular cyclopropanation of a 1,8-enyne substrate bearing a secondary ester group at the propargylic position to prepare a bicyclo[6.1.0]nonane core. Additional highlights include (i) an asymmetric Diels-Alder reaction to install the initial C5 stereogenic center of 1 and (ii) a sequential Pd-catalyzed Stille coupling, regio- and stereoselective Sharpless asymmetric dihydroxylation, and a subsequent intramolecular lactonization to construct the side chain of 1. The developed chemistry paves the way for the total syntheses of other family members bearing highly rigid bicyclo[6.1.0]nonane cores.

9.
Artigo em Inglês | MEDLINE | ID: mdl-30735775

RESUMO

Tyrosine hydroxylase (TH) is the initial enzyme responsible for cuticle sclerotization and pigmentation in many insect species, but to date, no direct functional studies have focused on TH in Zeugodacus tau. Here, the 3336-bp full-length cDNA of TH was isolated from Z. tau, a notorious horticultural pest infesting fruits and vegetables. qRT-polymerase chain reaction revealed that ZtTH transcripts were highly abundant at the time of pupal tanning and during adult emergence and were expressed in the midgut, integument and head of molting larvae. The pupation and eclosion rates gradually decreased when the 1st-instar larvae were fed diets containing higher concentrations of the TH inhibitor 3-iodo-tyrosine (3-IT). Moreover, pupal weights were significantly decreased, and abnormal uncolored phenotypes were observed after 20 mg/g 3-IT was incorporated into the diet. In addition, the suppression of TH function (mediated by RNA interference) led to a decrease in TH mRNAs and eclosion rates, accompanied by less-pigmented phenotypes. There was a severe impairment of larval-pupal cuticle tanning, leading to pupae with less yellowish pigment or that were completely white and transparent, when we injected 2 µL of 24.4 mM or 73.27 mM 3-IT into 3rd-instar larvae or prepupae. These results suggest that TH is an important enzyme for the normal growth and pupal pigmentation of Z. tau and that TH is a potential gene target for use in the control of Z. tau.


Assuntos
Pigmentação , Pupa/metabolismo , Tephritidae/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo , Animais , Fenótipo , Interferência de RNA , Análise de Sequência , Tephritidae/enzimologia , Tephritidae/genética , Tirosina 3-Mono-Oxigenase/deficiência , Tirosina 3-Mono-Oxigenase/genética
10.
Front Oncol ; 9: 1398, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31921655

RESUMO

Overexpression of drug efflux transport ABCB1 is correlated with multidrug resistance (MDR) among cancer cells. Upregulation of ABCB1 accounts for the recurrence of resistance to docetaxel therapy in ovarian cancer with poor survival. Erastin is a novel and specific small molecule that targets SLC7A11 to induce ferroptosis. In the present research, we explored the synergistic effect of erastin and docetaxel in ovarian cancer. We confirmed that the co-delivery of erastin with docetaxel significantly decreased cell viability, promoted cell apoptosis, and induced cell cycle arrest at G2/M in ovarian cancer cells with ABCB1 overexpression. Mechanistically, erastin dominantly elevated the intracellular ABCB1 substrate levels by restricting the drug-efflux activity of ABCB1 without alteration of the expression of ABCB1. Consequently, erastin can reverse ABCB1-mediated docetaxel resistance in ovarian cancer, revealing that the combination of erastin and docetaxel may potentially offer an effective administration for chemo-resistant patients suffering from ovarian cancers.

11.
Zootaxa ; 4701(1): zootaxa.4701.1.7, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-32229970

RESUMO

A new species of the genus Wesmaelia Foerster, 1863, Wesmaelia longius sp. n. is described and illustrated from the Palaearctic Region of China. A key to the Chinese species of the genus Wesmaelia is provided based on the key of Papp (1995).


Assuntos
Himenópteros , Vespas , Animais , China
12.
Org Lett ; 20(14): 4298-4301, 2018 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-29957964

RESUMO

Asymmetric total syntheses of insulicolide A, 14- O-acetylinsulicolide A, 6ß,9α-dihydroxy-14- p-nitrobenzoyl cinnamolide, and 7α,14-dihydroxy-6ß- p-nitrobenzoylconfertifolin have been achieved for the first time. The key steps in the synthesis include: (1) an iridium-catalyzed enantioselective polyene cyclization to construct the drimane core bearing two all-carbon quaternary chiral centers at C4 and C10 and (2) a cascade ozonolysis of the phenol ring to form the lactone fragment of the target molecules.

13.
J Org Chem ; 83(13): 6893-6906, 2018 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-29508610

RESUMO

The stereoselective construction of the CDEFGH ring system of lancifodilactone G is described. The key steps in this synthesis are (i) ring-closing metathesis for formation of the oxa-bridged eight-membered ring; (ii) an intramolecular Pauson-Khand reaction for construction of the sterically congested F ring; and (iii) sequential cross-metathesis, hydrogenation, and lactonization reactions for installation of the anomerically stabilized bis-spiro ketal fragment of lancifodilactone G.

14.
J Org Chem ; 83(13): 6907-6923, 2018 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-29508620

RESUMO

The asymmetric total synthesis of lancifodilactone G acetate was accomplished in 28 steps. The key steps in this synthesis include (i) an asymmetric Diels-Alder reaction for formation of the scaffold of the BC ring; (ii) an intramolecular ring-closing metathesis reaction for the formation of the trisubstituted cyclooctene using a Hoveyda-Grubbs II catalyst; (iii) an intramolecular Pauson-Khand reaction for construction of the sterically congested F ring; (iv) sequential cross-metathesis, hydrogenation, and lactonization reactions for installation of the anomerically stabilized bis-spiro ketal fragment of lancifodilactone G; and (v) a Dieckmann-type condensation reaction for installation of the A ring. The strategy and chemistry developed for the total synthesis will be useful in the synthesis of other natural products and complex molecules.

15.
Org Lett ; 19(15): 3986-3989, 2017 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-28726426

RESUMO

Novel oxazaborolidines activated by the strong acid triflimide or AlBr3 form cationic chiral catalysts. These are effective catalysts for highly regio- and enantioselective Diels-Alder reactions using substituted (E)-4-oxopent-2-enoates as dienophiles.

16.
J Am Chem Soc ; 139(16): 5732-5735, 2017 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-28391693

RESUMO

Asymmetric total synthesis of structurally intriguing and highly oxygenated lancifodilactone G acetate (7) has been achieved for the first time in 28 steps from a cheap commodity chemical, 2-(triisopropylsiloxy)-1,3-butadiene.


Assuntos
Acetatos/síntese química , Triterpenos/síntese química , Acetatos/química , Cristalografia por Raios X , Modelos Moleculares , Conformação Molecular , Triterpenos/química
17.
Zootaxa ; 4232(4): zootaxa.4232.4.3, 2017 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-28264350

RESUMO

A new species of the genus Dacnusa from the Palaearctic region of China, Dacnusa (Pachysema) heterodentatus sp. nov. is described. As well, three newly recorded species from the Palaearctic region in China are reported, along with their descriptions and illustrations: Dacnusa (Agonia) adducta (Haliday), Dacnusa (Aphanta) sasakawai Takada and Dacnusa (Dacnusa) maculipes Thomson. A key is presented to the subgenera of Dacnusa and the most similar species to these four reported species.


Assuntos
Himenópteros , Animais , China , Vespas
18.
Nat Commun ; 8: 14233, 2017 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-28139648

RESUMO

Complex natural products are a proven and rich source of disease-modulating drugs and of efficient tools for the study of chemical biology and drug discovery. The architectures of complex natural products are generally considered to represent significant barriers to efficient chemical synthesis. Here we describe a concise and efficient asymmetric synthesis of 19-dehydroxyl arisandilactone A-which belongs to a family of architecturally unique, highly oxygenated nortriterpenoids isolated from the medicinal plant Schisandra arisanensis. This synthesis takes place by means of a homo-Michael reaction, a tandem retro-Michael/Michael reaction, and Cu-catalysed intramolecular cyclopropanation as key steps. The proposed mechanisms for the homo-Michael and tandem retro-Michael/Michael reactions are supported by density functional theory (DFT) calculation. The developed chemistry may find application for the synthesis of its other family members of Schisandraceae nortriterpenoids.


Assuntos
Materiais Biomiméticos/síntese química , Técnicas de Química Sintética , Ciclopropanos/química , Triterpenos/síntese química , Catálise , Humanos , Estrutura Molecular , Teoria Quântica , Schisandra/química , Estereoisomerismo , Triterpenos/química
19.
J Med Entomol ; 54(2): 396-402, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28028142

RESUMO

Mosquitoes, which transmit infectious diseases, such as malaria and dengue fever, are harmful to human health. Thus, accurate and rapid identification of vectors is a critical step for the control of mosquito-borne diseases. However, phenotypic variations in adults, lack of recognizable features of the immature, and fragility of mosquitoes make identification difficult. Molecular approaches have been widely applied to identify mosquitoes, yet these methods have been focused only on the identification of a few species. This study used sequences of two mitochondrial genes, COI and ND2, and a ribosomal gene, ITS2, to design species-specific probes. Biochips thus developed were able to provide simultaneous identification of nine important medical and veterinary species, including the immature, from genera of Aedes, Anopheles, Armigeres, and Culex. This chip was also applied to samples collected from the field. Despite its inability to resolve the close affinity species of Culex quinquefasciatus and Culex pipiens molestus, pertinent biochips are expected to be applied to a mass screening method.


Assuntos
Culicidae/classificação , DNA Espaçador Ribossômico/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Proteínas de Insetos/genética , Insetos Vetores/classificação , Mitocôndrias/genética , NADH Desidrogenase/genética , Animais , Culicidae/genética , Culicidae/metabolismo , DNA Espaçador Ribossômico/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Feminino , Proteínas de Insetos/metabolismo , Insetos Vetores/genética , Masculino , Mitocôndrias/metabolismo , NADH Desidrogenase/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Especificidade da Espécie
20.
Org Biomol Chem ; 14(47): 11148-11153, 2016 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-27830850

RESUMO

A facile synthesis of quinolinones through intramolecular addition of diarylmethanols to α,ß-unsaturated amides promoted by KOt-Bu/DMF is reported. A series of 3,4-disubstituted quinolinones were obtained in moderate to good yields. A reaction pathway via the ketyl radical is proposed.

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