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1.
Nature ; 600(7887): 59-63, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34666339

RESUMEN

Mare volcanics on the Moon are the key record of thermo-chemical evolution throughout most of lunar history1-3. Young mare basalts-mainly distributed in a region rich in potassium, rare-earth elements and phosphorus (KREEP) in Oceanus Procellarum, called the Procellarum KREEP Terrane (PKT)4-were thought to be formed from KREEP-rich sources at depth5-7. However, this hypothesis has not been tested with young basalts from the PKT. Here we present a petrological and geochemical study of the basalt clasts from the PKT returned by the Chang'e-5 mission8. These two-billion-year-old basalts are the youngest lunar samples reported so far9. Bulk rock compositions have moderate titanium and high iron contents  with KREEP-like rare-earth-element and high thorium concentrations. However, strontium-neodymium isotopes indicate that these basalts were derived from a non-KREEP mantle source. To produce the high abundances of rare-earth elements and thorium, low-degree partial melting and extensive fractional crystallization are required. Our results indicate that the KREEP association may not be a prerequisite for young mare volcanism. Absolving the need to invoke heat-producing elements in their source implies a more sustained cooling history of the lunar interior to generate the Moon's youngest melts.

2.
Org Lett ; 23(12): 4876-4881, 2021 06 18.
Artículo en Inglés | MEDLINE | ID: mdl-34076432

RESUMEN

The development of a stereoselective method for the rapid assembly of structurally complex molecules remains fascinating and challenging in synthetic organic chemistry. Here, we report an enantioselective domino reaction between 3-vinylindole and p-quinone methide for the preparation of 3-indolyl cyclopenta[b]indoles containing multiple chiral centers. Chiral imidodiphosphoric acids enable this cascade asymmetric process, delivering a series of products with excellent yields (≤99%), enantioselectivities (≤99%), and diastereoselectivities (≤20:1 dr).

3.
Chem Commun (Camb) ; 57(18): 2313-2316, 2021 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-33533784

RESUMEN

An efficient method to construct enantioenriched spiro[benzofuro-cyclopenta[1,2-b]indole-indoline] scaffolds via consecutive cyclization is described here. The new scaffolds possess five successive chiral stereogenic centers and two spiroheterocycles. A range of highly enantioenriched scaffolds has been obtained with up to 93% yield, 99% ee and >19 : 1 d.r. catalyzed by Brønsted acid catalysts.

4.
J Org Chem ; 84(19): 12562-12572, 2019 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-31539475

RESUMEN

Chiral imidodiphosphoric acids were employed as efficient catalysts in the enantioselective addition reaction of pyrrole and indoles to 3-vinylindoles. A series of optically active 1,1,1-triarylethmanes bearing quaternary stereocenters were synthesized in excellent yields (up to 99% yield) and enantioselectivities (up to 98% ee). Gram-scale reactions of 1i and 2a as well as 1o and 5a demonstrated the synthetic utility of this methodology. Control experiments showed that the formation of a double H-bond between the catalyst and substrates is necessary for an excellent outcome.

5.
Dongwuxue Yanjiu ; 34(1): 21-6, 2013 Feb.
Artículo en Chino | MEDLINE | ID: mdl-23389974

RESUMEN

Correlations of two species of gamasid mites (Macronyssus pararadovskyi and M. radovskyi) and their bat hosts (Tylonycteris pachypus and T. robustula) were studied by field surveys and indoor behavioral experiments. The wild data indicated that mite load was positively correlated with body condition index of female T. pachypus hosts (Spearman: r (s)=0.55, P<0.01, n=24). Whereas, mite loads had no correlation with body condition indexes of male T. pachypus and all T. robustula hosts (P>0.05). Indoor original host infection showed that mites preferred male T. pachypus and T. robustula hosts. The infection percentages on male hosts were significantly higher than those on female hosts [T. pachypus: male (58±12)%, female (42±12)%, (t=-3.6, df=31, P<0.01); T. robustula: male (63±11)%, female (37±11)%, (t=-6.1, df=26, P<0.001)]. Using M. pararadovskyi (original host T. pachypus) to across infect T. pachypus and T. robustula, we found that mites significantly preferred the original host (t=9.1, df=29, P<0.001). The infection percentages of T. pachypus, and T. robustula were (71±13)% and (29±13)%, respectively. Our results indicated that mite loads of the two bat species were not correlated with body condition indexes of hosts. However, these mites presented different host sexual preferences, and the mites of T. pachypus presented specific host species preferences.


Asunto(s)
Quirópteros/parasitología , Especificidad del Huésped , Ácaros/fisiología , Animales , Quirópteros/clasificación , Femenino , Masculino , Factores Sexuales , Especificidad de la Especie , Factores de Tiempo
6.
Dongwuxue Yanjiu ; 34(6): 596-600, 2013 Dec.
Artículo en Chino | MEDLINE | ID: mdl-24415692

RESUMEN

Grooming behavior is evolved in animals in response to the costs associated with ectoparasites. In this study, ecotparasite densities and grooming behavior-including licking and scratching-of wild-caught lesser bamboo bat (Tylonycteris pachypus) and greater bamboo bat (T. robustula) were analyzed. The results indicated that both the frequencies and durations of licking were higher than those of scratching in both bat species, though T. pachypus licked more but scratched less than T. robustula. There were no difference in the durations of licking and scratching between the two bat species, and the durations and frequencies of grooming behavior of the two bat species were irrelevant with ectoparasite densities. These findings suggest that the grooming behavior of T. pachypus and T. robustula might be modulated by both the central control (programmed grooming) model and the peripheral stimulation (stimulus driven) model.


Asunto(s)
Quirópteros/fisiología , Quirópteros/parasitología , Interacciones Huésped-Parásitos , Parásitos/fisiología , Animales , Aseo Animal
7.
Nan Fang Yi Ke Da Xue Xue Bao ; 31(3): 529-30, 2011 Mar.
Artículo en Chino | MEDLINE | ID: mdl-21421499

RESUMEN

OBJECTIVE: To investigate the influences of total abdominal and laparoscopically hysterectomy on coagulation and fibrinolytic functions. METHODS: Blood samples were taken from 20 patients without high-risk factor of thrombosis before and after total abdominal and laparoscopically hysterectomy. The values of PT, APTT, FG, D-Dimer and AT-III were measured. RESULTS: The values of PT and AT-III significantly decreased while D-Dimer significantly increased after the operations. These changes were more obvious in patients undergoing abdominal hysterectomy. No significant changes in APTT or FG were noted after hysterectomy. CONCLUSIONS: Patients undergoing hysterectomy are at risk of developing thromboembolism, but the laparoscopic approach can significantly lower this risk as compared with abdominal hysterectomy.


Asunto(s)
Histerectomía/efectos adversos , Laparoscopía/efectos adversos , Tromboembolia/diagnóstico , Pruebas de Coagulación Sanguínea , Femenino , Humanos , Histerectomía/métodos , Tiempo de Tromboplastina Parcial , Factores de Riesgo , Tromboembolia/etiología
8.
Chem Commun (Camb) ; 46(10): 1721-3, 2010 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-20177628

RESUMEN

Mn(iii)-mediated phosphonations of carbon-carbon double and triple bonds to form alkenylphosphonates are introduced.


Asunto(s)
Alquenos/química , Alquinos/química , Manganeso/química , Organofosfonatos/química , Catálisis , Radicales Libres/química , Oxidación-Reducción , Estereoisomerismo
9.
Nan Fang Yi Ke Da Xue Xue Bao ; 29(7): 1479-81, 2009 Jul.
Artículo en Chino | MEDLINE | ID: mdl-19620087

RESUMEN

OBJECTIVE: To detect the expression of fragile histidine triad in endometriosis and investigate the pathogenesis of endometriosis. METHODS: immunohistochemistry was used to examine the expression of Fhit in the eutopic and ectopic endometria of 58 patients with endometriosis and in the endometria in 15 patients with hysteromyoma. RESULTS: The intensity of Fhit expression decreased in the order of normal endometrium, eutopic endometrium in endometriosis group, and ectopic endometrium. In patients with endometriosis, Fhit expression in the eutopic and ectopic endometria in proliferative phase showed no significant difference from that in secretory phase (P>0.05). Fhit expression in the ectopic endometrium showed significant difference between different r-AFS stages. MOD of ectopic endometrium in stages I-II was significantly higher than that in stages III-IV (P<0.05), but Fhit expression in the eutopic endometrium showed no significant difference (P>0.05). MOD of ovarian endometriosis showed no difference with that of adenomyosis. CONCLUSIONS: Fhit may play an important role in the development of endometriosis.


Asunto(s)
Ácido Anhídrido Hidrolasas/metabolismo , Endometriosis/metabolismo , Endometrio/metabolismo , Proteínas de Neoplasias/metabolismo , Adulto , Endometriosis/patología , Femenino , Humanos , Persona de Mediana Edad
11.
Zhonghua Yi Xue Za Zhi ; 85(3): 177-80, 2005 Jan 19.
Artículo en Chino | MEDLINE | ID: mdl-15854463

RESUMEN

OBJECTIVE: To evaluate the effect of laparoscopic surgery on and lipid hyperoxidation in patients with hysteromyoma. METHODS: Forty patients with hysteromyoma were randomly divided into 2 equal groups: laparoscopy group and laparotomy group. The plasma advanced oxidation protein products (AOPP), malondialdehyde (MDA), antioxidant activity (AOA), and glutathione peroxidase (GPx) activity were measured before operation, just after operation (5 minutes after deflation) and 24 hours after operation. RESULTS: (1) In the laparoscopy group, the levels of AOPP and MDA were (50.20 +/- 9.23) micromol/L and (1.85 +/- 0.19) micromol/L before operation, increased significantly just after operation [(68.75 +/- 12.69) micromol/L and (2.52 +/- 0.55) micromol/L respectively, both P < 0.01], and recovered to the normal level 24 hour postoperatively [(49.70 +/- 9.92) micromol/L and (2.05 +/- 0.68) micromol/L respectively, both P > 0.05]. The levels of GPx and AOA decreased significantly just after operation [(0.29 +/- 0.09) U/ml vs. (0.62 +/- 0.27) U/mL and (0.90 +/- 0.24) mmol/L vs. (1.41 +/- 0.39) mmol/L respectively, both P < 0.01], and the GPx level recovered 24 hours after operation [(0.52 +/- 0.06) U/mL, P > 0.05], however, the AOA level was still lower [(1.00 +/- 0.31) mmol/L, P < 0.01]. In the laparotomy group, the levels of plasma AOPP and MDA level slightly increased just after operation in comparison with those before operation [(53.39 +/- 9.86) micromol/L vs. (52.30 +/- 7.10) micromol/L and (2.09 +/- 0.51) micromol/L vs. (1.83 +/- 0.64) micromol/L respectively, both P > 0.05] and continued to increase 24 hours after operation [(63.40 +/- 15.5) micromol/L, P < 0.05, and (2.42 +/- 0.44) micromol/L, P < 0.01]; the GPx and AOA levels decreased a little just after operation [(0.51 +/- 0.17) U/mL vs. (0.57 +/- 0.21) U/mL and (1.20 +/- 0.46) mmol/L vs. (1.33 +/- 0.37) mmol/L, both P > 0.05] and continued to decrease 24 hours after operation [(0.35 +/- 0.19) U/mL and (0.92 +/- 0.22) mmol/L respectively, both P < 0.01]. Compared with those of the laparotomy group, the plasma AOPP and MDA levels of the laparoscopy group were both significantly lower (P < 0.01 and P < 0.05), and the GPx level was significantly higher (P < 0.01) 24 hours after operation, however, the AOA level was not significantly different (P > 0.05). CONCLUSION: Laparoscopic surgery is better than laparotomy. Protein oxidation and lipid hyperoxidation occur during the laparoscopic surgery, however, disappeared after operation. Free radicals are generated by the end of laparoscopic procedure, possibly as a result of an ischemia-reperfusion phenomenon induced by the inflation and deflation of the pneumoperitoneum. AOPP and MDA are induced during laparoscopic procedure and then return to the normal levels finally.


Asunto(s)
Laparoscopía , Leiomioma/cirugía , Metabolismo de los Lípidos , Neoplasias Uterinas/cirugía , Adulto , Proteínas Sanguíneas/metabolismo , Femenino , Glutatión Peroxidasa/metabolismo , Humanos , Leiomioma/metabolismo , Malondialdehído/metabolismo , Oxidación-Reducción , Proteínas Serina-Treonina Quinasas/metabolismo , Neoplasias Uterinas/metabolismo
12.
Di Yi Jun Yi Da Xue Xue Bao ; 24(9): 1087-8, 2004 Sep.
Artículo en Chino | MEDLINE | ID: mdl-15447875

RESUMEN

OBJECTIVE: To investigate the effects of laparoscopy in treating ectopic pregnancy complicated with intrauterine pregnancy. METHOD: Laparoscopy was performed in 5 patients with ectopic pregnancy complicated with intrauterine pregnancy. RESULTS: The ectopic pregnancy tissue or the damaged fallopian tube was successfully excised laparoscopically. CONCLUSION: Laparoscopy is safe for treating ectopic pregnancy complicated with intrauterine pregnancy, causing minimal injuries and less disturbance to intrauterine pregnancy and ensuring rapid recovery.


Asunto(s)
Laparoscopía , Embarazo Tubario/cirugía , Adulto , Femenino , Procedimientos Quirúrgicos Ginecológicos/métodos , Humanos , Embarazo , Primer Trimestre del Embarazo
13.
Di Yi Jun Yi Da Xue Xue Bao ; 24(8): 907-9, 2004 Aug.
Artículo en Chino | MEDLINE | ID: mdl-15321758

RESUMEN

OBJECTIVE: To evaluate the impact of laparoscopic surgery on oxidative stress in patients with uterine myomas. METHODS: Plasma malondialdehyde (MDA), antioxidant activity (AOA), and glutathione peroxidase (GPx) activity in 20 patients with uterine myomas were measured before, at the end of (5 min after deflation), and 24 h after laparoscopic surgery, for comparison with the measurements in 20 patients receiving laparotomic surgery at the same time points. RESULTS: Immediately following laparoscopic surgery, plasma MDA level increased significantly as compared with the preoperative level (P<0.01) and recovered the normal level 24 h after the operation; but in laparotomic surgery, plasma MDA level underwent a slight increase in the immediately early postoperative stage and continued to increase 24 h after the operation. In laparoscopic surgery, GPx and AOA decreased significantly in the early postoperative stage (P<0.01) and recovered to some extent 24 h postoperatively, whereas in laparotomic surgery, GPx and AOA slightly decreased immediately following the operation and further decreased 24 h after the operation. Compared with patients receiving laparotomic surgery, laparoscopic patients had significantly lower plasma MDA level (P<0.01) and significantly higher GPx activity (P<0.01) with comparable AOA level (P=0.33) 24 h after the operation. CONCLUSION: Free radical produces at the end of a laparoscopic procedure, possibly as a result of ischemia-reperfusion induced by the inflation and deflation of the pneumoperitoneum.


Asunto(s)
Laparoscopía/efectos adversos , Leiomioma/cirugía , Procedimientos Quirúrgicos Obstétricos/métodos , Estrés Oxidativo/fisiología , Neoplasias Uterinas/cirugía , Adulto , Femenino , Glutatión Peroxidasa/sangre , Humanos , Leiomioma/metabolismo , Malondialdehído/sangre , Procedimientos Quirúrgicos Obstétricos/efectos adversos , Neoplasias Uterinas/metabolismo
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