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1.
Plant Physiol ; 193(1): 627-642, 2023 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-37233029

RESUMEN

Protecting haploid pollen and spores against UV-B light and high temperature, 2 major stresses inherent to the terrestrial environment, is critical for plant reproduction and dispersal. Here, we show flavonoids play an indispensable role in this process. First, we identified the flavanone naringenin, which serves to defend against UV-B damage, in the sporopollenin wall of all vascular plants tested. Second, we found that flavonols are present in the spore/pollen protoplasm of all euphyllophyte plants tested and that these flavonols scavenge reactive oxygen species to protect against environmental stresses, particularly heat. Genetic and biochemical analyses showed that these flavonoids are sequentially synthesized in both the tapetum and microspores during pollen ontogeny in Arabidopsis (Arabidopsis thaliana). We show that stepwise increases in the complexity of flavonoids in spores/pollen during plant evolution mirror their progressive adaptation to terrestrial environments. The close relationship between flavonoid complexity and phylogeny and its strong association with pollen survival phenotypes suggest that flavonoids played a central role in the progression of plants from aquatic environments into progressively dry land habitats.


Asunto(s)
Arabidopsis , Flavonoides , Plantas , Polen/genética , Arabidopsis/genética , Flavonoles , Esporas
2.
Mar Drugs ; 21(2)2023 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-36827110

RESUMEN

The present investigation of the South China Sea soft coral Sarcophyton trocheliophorum resulted in the discovery of six new polyoxygenated diterpenes, namely sartrocheliols A-E (1, 3, 5-8) along with four known ones, 2, 4, 9, and 10. Based on extensive spectroscopic data analysis, sartrocheliol A (1) was identified as an uncommon capnosane diterpene, while sartrocheliols B-E (3, 5-8) were established as cembrane diterpenes. They displayed diverse structural features not only at the distinctly different carbon frameworks but also at the various types of heterocycles, including the epoxide, γ-lactone, furan, and pyran rings. Moreover, their absolute configurations were determined by a combination of quantum mechanical-nuclear magnetic resonance (QM-NMR) approach, modified Mosher's method, and X-ray diffraction analysis. In the anti-tumor bioassay, compound 4 exhibited moderate cytotoxic activities against A549, H1975, MDA-MB-231, and H1299 cells with the IC50 values ranging from 26.3 to 47.9 µM.


Asunto(s)
Antozoos , Diterpenos , Animales , Estructura Molecular , Antozoos/química , Espectroscopía de Resonancia Magnética , Diterpenos/química , China
3.
Chem Biodivers ; 20(4): e202300217, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36855273

RESUMEN

Two new highly functionalized cembrane diterpenoids named ximaolobophytolides A (1) and B (2) as minor components, together with seven related known compounds (3-9), have been isolated and identified from the Ximao soft coral Lobophytum sp. They were characterized by the presence of an α-methylene-γ-lactone moiety. Based on the comprehensive analyses of 1D and 2D NMR spectroscopic data, the absolute configurations of these two new compounds were elucidated by the combination of quantum mechanical (QM)-NMR and time-dependent density functional theory/electronic circular dichroism (TDDFT-ECD) calculation approaches. In the anti-tumor bioassays, compounds 3-9 showed moderate to significant inhibitory effects (IC50 values ranging from 29.66 to 0.39 µM) against the proliferations of five tumor cells HEL, A549, H1975, MDA-MB-231, and H1299. It might be worthy to point out that compounds 4, 7, and 8 exhibited better anti-tumor activities than that of the positive control Doxorubicin.


Asunto(s)
Antozoos , Diterpenos , Neoplasias , Animales , Antozoos/química , Espectroscopía de Resonancia Magnética , Diterpenos/farmacología , Diterpenos/química , China , Estructura Molecular
4.
J Asian Nat Prod Res ; 22(1): 69-82, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30588834

RESUMEN

Dozens of hybrids of natural alkaloid evodiamine/rutaecarpine and thieno[2,3-d]pyrimidinones were synthesized in a straightforward method by condensation of substituted 2H-thieno[2,3-d][1, 3]oxazine-2,4(1H)-diones or N-methyl-2H-thieno[2,3-d][1, 3]oxazine-2,4(1H)-dione with 3,4-dihydro-ß-carbolines. In vitro cytotoxic assay discovered that compounds 9a, 10e, 11a, 11d, 11f, and 12a could induce antiproliferation against four different types of human cancer cells while compounds 10f and 12e were inactive. Notably, compound 11a displayed potent cell cytotoxicity for human non-small cell lung cancer cells A549, PC-9, human prostate cancer cells PC-3, and human breast cancer cell line MCF-7. Furthermore, compound 11a exhibited strong colony formation inhibition to A549 cells. These results unfold potential anticancer therapeutic applications of hybrids of thieno[2,3-d]pyrimidinones and quinazolinones.


Asunto(s)
Alcaloides , Antineoplásicos , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Alcaloides Indólicos , Estructura Molecular , Pirimidinonas , Quinazolinas , Relación Estructura-Actividad
5.
BMC Cancer ; 19(1): 224, 2019 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-30866863

RESUMEN

BACKGROUND: Our previous works have demonstrated that 8-bromo-7-methoxychrysin suppressed stemness of human hepatocellular carcinoma (HCC) cell line SMMC-7721 induced by condition medium from hepatic stellate cell line LX-2 that was activated by liver cancer stem-like cells (LCSCs). However, whether and whereby BrMC inhibits the stemness induced by co-culture of LCSCs and LX-2 cells remains to be investigated. METHODS: The second-generation spheres by sphere culture were identified and used as SMMC-7721-and MHCC97H-derived LCSLCs. SMMC-7721-and MHCC97-derived LCSCs/LX-2 cells transwell co-culture system was treated with BrMC and its lead compound chrysin. The concentrations of IL-6, IL-8, HGF and PDGF in condition medium from co-culture were measured by enzyme-linked immunosorbent assay (ELISA). The stemness of SMMC-7721 cells was evaluated by sphere formation assay and western blot analysis for expression levels of cancer stem cell markers (CD133 and CD44).The expression levels of cancer-associated fibroblast markers (FAP-α and α-SMA) were employed to evaluate pathologic activation of LX-2 cells. Addition of IL-6 and/or HGF or deletion of IL-6 and/or HGF was conducted to investigate the mechanisms for BrMC and chrysin treatment in SMMC-7721-derived LCSLCs co-cultured with LX-2cells. RESULTS: The co-culture of LCSLCs with LX-2 cells increased sphere formation capability as well as expression of CD133 and CD44 in SMMC-7721 cells, meanwhile, upregulated expression of FAP-α in LX-2 cells. ELISA indicated that the concentrations of IL-6 and HGF were significantly elevated in Co-CM than that of condition media from co-cultured SMMC-7721 cells/LX-2 cells. Treatment of BrMC and chrysin with co-cultures of SMMC-7721- and MHCC97H-derived LCSLCs and LX-2 cells effectively inhibited the above responses. Moreover, addition of IL-6 and/or HGF induced stemness of SMMC-7721 cells and activation of LX-2 cells, conversely, deletion of IL-6 and/or HGF suppressed those. Furthermore, the inhibitory effects of BrMC and chrysin on stemness of SMMC-7721 cells and activation of LX-2 cells were attenuated by addition of IL-6 or HGF, and enhanced by deletion of IL-6 or HGF. CONCLUSIONS: Our results suggest IL-6 and HGF may be the key communication molecules for the interaction between LCSLCs and HSCs, and BrMC and chrysin could block these effects and be the novel therapeutic candidates for HCC management.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , Flavonoides/farmacología , Células Estrelladas Hepáticas/metabolismo , Neoplasias Hepáticas/metabolismo , Células Madre Neoplásicas/metabolismo , Animales , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Técnicas de Cocultivo , Relación Dosis-Respuesta a Droga , Femenino , Células Estrelladas Hepáticas/efectos de los fármacos , Células Estrelladas Hepáticas/patología , Humanos , Interleucina-6/antagonistas & inhibidores , Interleucina-6/metabolismo , Interleucina-8/antagonistas & inhibidores , Interleucina-8/metabolismo , Neoplasias Hepáticas/patología , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/patología , Ensayos Antitumor por Modelo de Xenoinjerto/métodos
7.
Mol Cell Proteomics ; 14(9): 2510-34, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26091698

RESUMEN

Fern spore is a good single-cell model for studying the sophisticated molecular networks in asymmetric cell division, differentiation, and polar growth. Osmunda cinnamomea L. var. asiatica is one of the oldest fern species with typical separate-growing trophophyll and sporophyll. The chlorophyllous spores generated from sporophyll can germinate without dormancy. In this study, the spore ultrastructure, antioxidant enzyme activities, as well as protein and gene expression patterns were analyzed in the course of spore germination at five typical stages (i.e. mature spores, rehydrated spores, double-celled spores, germinated spores, and spores with protonemal cells). Proteomic analysis revealed 113 differentially expressed proteins, which were mainly involved in photosynthesis, reserve mobilization, energy supplying, protein synthesis and turnover, reactive oxygen species scavenging, signaling, and cell structure modulation. The presence of multiple proteoforms of 25 differentially expressed proteins implies that post-translational modification may play important roles in spore germination. The dynamic patterns of proteins and their encoding genes exhibited specific characteristics in the processes of cell division and rhizoid tip growth, which include heterotrophic and autotrophic metabolisms, de novo protein synthesis and active protein turnover, reactive oxygen species and hormone (brassinosteroid and ethylene) signaling, and vesicle trafficking and cytoskeleton dynamic. In addition, the function skew of proteins in fern spores highlights the unique and common mechanisms when compared with evolutionarily divergent spermatophyte pollen. These findings provide an improved understanding of the typical single-celled asymmetric division and polar growth during fern spore germination.


Asunto(s)
Germinación , Proteínas de Plantas/metabolismo , Polypodiaceae/crecimiento & desarrollo , Polypodiaceae/ultraestructura , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Polypodiaceae/fisiología , Proteómica/métodos , Análisis de la Célula Individual , Esporas/crecimiento & desarrollo , Esporas/ultraestructura
8.
Surg Endosc ; 29(6): 1384-93, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25303904

RESUMEN

BACKGROUND: Laparoscopic appendectomy (LA) has been rapidly applied worldwide recently. The issue of surgical site infection (SSI) after appendectomy needs to be re-investigated and analyzed along with this trend. This study aimed to identify risk factors of SSI after appendectomy in recent years. METHODS: This retrospective study was conducted among patients with acute appendicitis who underwent either laparoscopic or open appendectomy (OA) at 7 general hospitals in China from 2010 to 2013. The incidence of SSI, classified as incisional SSI and organ/space SSI, was investigated. A multivariate logistic regression model was used to assess independent risk factors associated with overall, incisional, and organ/space SSI, respectively. RESULTS: Among 16,263 consecutive patients, 3,422 (21.0 %) and 12,841 (79.0 %) patients underwent LA and OA, respectively. The incidences of overall, incisional, and organ/space SSI were 6.2, 3.7, and 3.0 %, respectively. The proportion of LAs among both procedures increased yearly from 5.3 to 46.5 %, while the incidences of overall and incisional SSI after appendectomy simultaneously decreased yearly from 9.6 to 4.5 % and from 6.7 to 2.2 %, respectively. In comparison with OA, LA was associated with lower incidences of overall and incisional SSI (4.5 vs 6.7 %, P < 0.001; and 1.9 vs 4.2 %, P < 0.001), but a similar incidence of organ/space SSI (3.0 vs 3.0 %, P = 0.995). After multivariate logistic regression analyses were performed, LA was found to be independently associated with a decrease in development of overall SSI [odds ratio (95 % confidence interval) OR (95 % CI), 1.24 (1.03-1.70); P = 0.04] or incisional SSI [OR (95 % CI), 1.32 (1.10-1.68); P = 0.01]. CONCLUSION: With the increasing application trends of laparoscopic procedure, the incidence of SSI after appendectomy declined accordingly. Compared with OA, LA was independently associated with a significantly lower incidence of incisional SSI, but a similar incidence of organ/space SSI.


Asunto(s)
Apendicectomía/efectos adversos , Apendicitis/cirugía , Laparoscopía/efectos adversos , Infección de la Herida Quirúrgica/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Apendicectomía/métodos , Niño , Preescolar , China , Estudios de Cohortes , Femenino , Humanos , Incidencia , Lactante , Modelos Logísticos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Estudios Retrospectivos , Factores de Riesgo , Infección de la Herida Quirúrgica/etiología , Adulto Joven
9.
Chin J Integr Med ; 29(3): 224-232, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35809177

RESUMEN

OBJECTIVE: To explore whether casticin (CAS) suppresses stemness in cancer stem-like cells (CSLCs) obtained from human cervical cancer (CCSLCs) and the underlying mechanism. METHODS: Spheres from HeLa and CaSki cells were used as CCSLCs. DNA methyltransferase 1 (DNMT1) activity and mRNA levels, self-renewal capability (Nanog and Sox2), and cancer stem cell markers (CD133 and CD44), were detected by a colorimetric DNMT activity/inhibition assay kit, quantitative real-time reverse transcription-polymerase chain reaction, sphere and colony formation assays, and immunoblot, respectively. Knockdown and overexpression of DNMT1 by transfection with shRNA and cDNA, respectively, were performed to explore the mechanism for action of CAS (0, 10, 30, and 100 nmol/L). RESULTS: DNMT1 activity was increased in CCSLCs compared with HeLa and CaSki cells (P<0.05). In addition, HeLa-derived CCSLCs transfected with DNMT1 shRNA showed reduced sphere and colony formation abilities, and lower CD133, CD44, Nanog and Sox2 protein expressions (P<0.05). Conversely, overexpression of DNMT1 in HeLa cells exhibited the oppositive effects. Furthermore, CAS significantly reduced DNMT1 activity and transcription levels as well as stemness in HeLa-derived CCSLCs (P<0.05). Interestingly, DNMT1 knockdown enhanced the inhibitory effect of CAS on stemness. As expected, DNMT1 overexpression reversed the inhibitory effect of CAS on stemness in HeLa cells. CONCLUSION: CAS effectively inhibits stemness in CCSLCs through suppression of DNMT1 activation, suggesting that CAS acts as a promising preventive and therapeutic candidate in cervical cancer.


Asunto(s)
Neoplasias del Cuello Uterino , Femenino , Humanos , Línea Celular Tumoral , Células HeLa , Células Madre Neoplásicas/metabolismo , ARN Interferente Pequeño/metabolismo , Neoplasias del Cuello Uterino/metabolismo
10.
Sex Plant Reprod ; 25(1): 61-9, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22167247

RESUMEN

The development of the egg and canal cells in the fern Osmunda japonica Thunb. was studied during oogenesis by transmission electron microscopy. The mature egg possesses no fertilization pore and no typical egg envelope. In addition, an extra wall formed around the canal cells during oogenesis and apparently blocked protoplasmic connections between the egg and the canal cells. The periodic acid Schiff (PAS) reaction revealed that the extra wall was most likely composed of polysaccharides. Maturation of the egg was accompanied by the formation of a separation cavity above the egg and by some changes in the morphology of the nucleus and cytoplasmic organelles. The chromatin of the nucleus becomes condensed and the upper surface of the nucleus becomes closely associated with the plasmalemma. Amyloplasts in the egg cytoplasm were numerous and conspicuous, with most in close proximity to the nucleus. Finally, the cytoplasm on one side of the egg became vesiculated and the overlying plasmalemma was easily disrupted. These cytological features of the egg and the canal cells during oogenesis in O. japonica are markedly different from those of the leptosporangiate ferns and suggest a significant evolutionary divergence in reproductive cellular features between Osmundaceae and leptosporangiate ferns.


Asunto(s)
Helechos/ultraestructura , Gametogénesis en la Planta , Óvulo Vegetal/embriología , Evolución Biológica , Helechos/embriología , Helechos/fisiología
11.
Sex Plant Reprod ; 25(2): 147-56, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22476325

RESUMEN

Egg development in Pteridium aquilinum var. latiusculum was studied using ultrastructural and cytochemical methods to examine structural features influencing fertilization in leptosporangiate ferns. Ultrastructural observations indicate a separation cavity is first formed above the egg during oogenesis with a pore region persistently connecting the egg and the ventral canal cell. The egg envelope is formed by deposition of amorphous materials in the separation cavity on the outer surface of plasmalemma. The egg envelope was not formed across the pore region; instead, a fertilization pore was formed. During oogenesis, the egg nucleus produced extensive evaginations containing osmiophilic bodies. Cytochemical experiments revealed that the egg envelope displays strong periodic acid-Schiff reaction indicative of polysaccharides, with negligible Sudan black B staining for lipids, suggesting that the egg envelope is composed principally of polysaccharides, and not lipids. The present manuscript provides new insights into egg structure and development of Pteridium, including discovery and characterization of the fertilization pore and observations on the chemical nature of the egg envelope, thus contributing to the understanding of the cytological mechanism of the sexual reproduction of ferns.


Asunto(s)
Gametogénesis en la Planta/fisiología , Pteridium/citología , Pteridium/ultraestructura , Membrana Celular/metabolismo , Membrana Celular/ultraestructura , Fertilización , Células Germinativas de las Plantas/citología , Células Germinativas de las Plantas/ultraestructura
12.
Mol Cell Biochem ; 363(1-2): 147-55, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22198288

RESUMEN

7-Difluoromethyl-5,4'-dimethoxygenistein (DFMG) is an active new derivative of genistein (GEN). It has shown effective protection in vascular endothelial injury. To further investigate its potential protective effects and its mechanism probably related to atherosclerosis, in present study, human aorta endothelial cells (HAECs) were chosen and treated with various concentrations of lysophosphatidyl choline (LPC) to establish an experimental model. Results showed that 10.0 µmol/l of LPC was optimal for inducing HAEC injury. DFMG pretreatment was able to prevent HAEC injury induced by LPC and restore cell viability in a concentration-dependent manner. The protective efficacy of DFMG (10.0 µmol/l) was significantly greater than that of GEN (10.0 µmol/l) and vitamin E (50.0 µmol/l). The mechanisms underlying the protective effects of DFMG are related to the activation of the antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase and to the clearance of intracellular reactive oxygen species. DFMG inhibits the apoptosis of HAECs mediated by LPC involving the blockage of the mitochondrial apoptotic pathway.


Asunto(s)
Antioxidantes/farmacología , Aorta/efectos de los fármacos , Células Endoteliales/efectos de los fármacos , Genisteína/análogos & derivados , Lisofosfatidilcolinas/toxicidad , Aorta/metabolismo , Aorta/patología , Apoptosis/efectos de los fármacos , Caspasas/metabolismo , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Citocromos c/metabolismo , Citoprotección , Relación Dosis-Respuesta a Droga , Células Endoteliales/metabolismo , Células Endoteliales/patología , Genisteína/farmacología , Glutatión Peroxidasa/metabolismo , Humanos , L-Lactato Deshidrogenasa/metabolismo , Malondialdehído/metabolismo , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Mitocondrias/patología , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Superóxido Dismutasa/metabolismo , Vitamina E/farmacología
14.
BMC Cancer ; 11: 322, 2011 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-21801359

RESUMEN

BACKGROUND: 5-allyl-7-gen-difluoromethoxychrysin (AFMC) is a novel synthetic analogue of chrysin that has been reported to inhibit proliferation in various cancer cell lines. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising anti-cancer agent. METHODS: The cytotoxicity of A549 and WI-38 cells were determined using colorimetry. Apoptosis was detected by flow cytometry (FCM) after propidium iodide (PI) fluorescence staining and agarose gel electrophoresis. Caspase activities were evaluated using enzyme-linked immunosorbent assay (ELISA).The expressions of DR4 and DR5 were analyzed using FCM and western blot. RESULTS: Subtoxic concentrations of AFMC sensitize human non-small cell lung cancer (NSCLC) A549 cells to TRAIL-mediated apoptosis. Combined treatment of A549 cells with AFMC and TRAIL significantly activated caspase-3, -8 and -9. The caspase-3 inhibitor zDEVD-fmk and the caspase-8 inhibitor zIETD-fmk blocked the apoptosis of A549 cells induced by co-treatment with AFMC and TRAIL. In addition, we found that treatment of A549 cells with AFMC significantly induced the expression of death receptor 5 (DR5). AFMC-mediated sensitization of A549 cells to TRAIL was efficiently reduced by administration of a blocking antibody or small interfering RNAs against DR5. AFMC also caused increase of the Sub-G1 cells by TRAIL treatment and increased the expression levels of DR5 in other NSCLC H460 and H157 cell lines. In contrast, AFMC-mediated induction of DR5 expression was not observed in human embryo lung WI-38 cells, and AFMC did not sensitize WI-38 cells to TRAIL-induced apoptosis. CONCLUSIONS: AFMC synergistically enhances TRAIL-mediated apoptosis in NSCLC cells through up-regulating DR5 expression.


Asunto(s)
Apoptosis/efectos de los fármacos , Flavonoides/farmacología , Ligando Inductor de Apoptosis Relacionado con TNF/farmacología , Anticuerpos Bloqueadores/inmunología , Anticuerpos Bloqueadores/farmacología , Western Blotting , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Inhibidores de Caspasas , Caspasas/metabolismo , Línea Celular , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Inhibidores de Cisteína Proteinasa/farmacología , Sinergismo Farmacológico , Activación Enzimática/efectos de los fármacos , Ensayo de Inmunoadsorción Enzimática , Flavonoides/química , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Interferencia de ARN , Receptores del Ligando Inductor de Apoptosis Relacionado con TNF/genética , Receptores del Ligando Inductor de Apoptosis Relacionado con TNF/inmunología , Receptores del Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo
15.
PhytoKeys ; 178: 81-94, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-36761040

RESUMEN

Although taxonomists target the remote wild regions to discover new species, taxa lacking a comprehensive and modern systematic treatment may be the new hotspot for biodiversity discovery. The development of molecular systematics integrated with microscopic observation techniques has greatly improved the ability of taxonomists to identify species correctly. Vittariacentrochinensis Ching ex J.F. Cheng, regarded as a synonym of Haplopterisfudzinoi (Makino) E.H.Crane, remained hidden from the eyes of fern taxonomists for more than 20 years. Herein, we collected several population samples of V.centrochinensis by performing molecular phylogenetic analysis of five cpDNA regions (rbcL, atpA, matK, ndhF, and trnL-trnF) and through micromophological observation of specimens which differs from H.fudzinoi by lamina width and exospores. Considering the differences in morphology, geographical range, and genetic distance between these two species, we formally recognized V.centrochinensis as an authentic species and proposed a new combination Haplopteriscentrochinensis (Ching ex J.F.Cheng) Y.H.Yan, Z.Y.Wei & X.C.Zhang, comb. nov. Our findings demonstrate that several taxa in synonyms are missing, and nowadays taxonomy should also include re-evaluation of the past taxonomy.

16.
PhytoKeys ; 186: 111-120, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35002359

RESUMEN

Dipterisshenzhenensis, a new species of ferns from Shenzhen, Guangdong, southern China, is identified and described. It closely resembles D.chinensis but possesses several unique traits, such as long rhizome scales, castaneous stipe, and abaxially pale fronds with two fan-shaped fronds connected by a broad wing. Molecular evidence showed that D.shenzhenensis is allied to D.conjugata, whereas it has morphologically significant differences (P < 0.05) on the basis of quantitative trait statistical analysis. Overall, the morphological evidence, taken together with the result of cpDNA indicated that D.shenzhenensis is a distinct species.

17.
J Integr Plant Biol ; 52(6): 518-27, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20590982

RESUMEN

The development of the fertilization pore during oogenesis of the fern Ceratopteris thalictroides was followed using transmission electron microscopy. The newly formed egg is appressed closely to the adjacent cells. There are well-developed plasmodesmata between the egg and the ventral canal cell, but none between the egg and the jacket cells of the archegonium. During maturation, a separation cavity is formed around the egg. However, a pore region persistently connects the egg and the ventral canal cell. The extra egg membrane is formed by deposition of sheets of endoplasmic reticulum (ER), but no ER is deposited on the inner surface of the pore region. Thus, a fertilization pore, covered by a layer of plasmalemma, is formed. The ventral canal cell undoubtedly participates the formation of the fertilization pore, probably by absorbing the sheets of ER beneath the pore region. The functional significance of the ventral canal cell in formation of the fertilization pore is discussed. The features of the mature egg include that abundant concentric membranes and osmiophilic vesicles occur in the cytoplasm of the mature egg. The initial, round nucleus of the egg eventually becomes cup-shaped. This investigation gives some new insights about the cells participating oogenesis in ferns.


Asunto(s)
Helechos/fisiología , Fertilización/fisiología , Gametogénesis en la Planta/fisiología , Helechos/ultraestructura , Microscopía Electrónica de Transmisión
18.
J Integr Plant Biol ; 52(3): 254-64, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20377686

RESUMEN

The cytological events, including nuclear fusion, digestion of male organelles and rebuilding of the plasmalemma and cell wall, during zygote formation of the fern Ceratopteris thalictroides (L.) Brongn. are described based on the observations of transmission electron microscopy. When the spermatozoid enters the egg and contacts the cytoplasm, the male chromatin relaxes continually. The microtubular ribbon (MTr) is separated from the male nucleus and then an envelope reappears around the male nucleus. During nuclear fusion, the egg nucleus becomes highly irregular and extends some nuclear protrusions. It is proposed that the protrusions fuse with the male nucleus actively. After nuclear fusion the irregular zygotic nucleus contracts gradually. It becomes spherical before the zygote divides. The male chromatin is identifiable as fibrous structure in the zygotic nucleus in the beginning, but it gradually becomes diffused completely. The male organelles, including the MTr, multilayered structure, flagella and the male mitochondria are finally digested in the zygotic cytoplasm. Finally a new plasmalemma and cell wall are formed outside the protoplast. The organelles in the zygote are rearranged, which produces a horizontal polarity zygote. The zygote divides with an oblique-vertical cell plate facing the apical notch of the gametophyte.


Asunto(s)
Helechos/citología , Helechos/fisiología , Fertilización/fisiología , Cigoto/citología , Núcleo Celular/ultraestructura , Pared Celular/ultraestructura , Células Germinativas de las Plantas/citología , Células Germinativas de las Plantas/ultraestructura , Fusión de Membrana , Factores de Tiempo
19.
J Cardiovasc Pharmacol ; 54(5): 412-20, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19730393

RESUMEN

Genistein is a phytoestrogen that is known to have a protective effect on the vascular endothelial wall. However, it exhibits poor bioavailability, which limits the use of genistein to treat cardiovascular and cerebrovascular diseases. A novel genistein derivative, 7-difluoromethyl-5,4'-dimethoxygenistein (dFMGEN), has shown a better protective effect on vascular endothelial damage in vitro than genistein. In this study, we further evaluated therapeutic effects of dFMGEN on the vascular endothelial wall and atherosclerosis in a rabbit model in vivo. There were 5 groups: the GEN group (genistein 5 mg/kg per day), lovastatin group (lovastatin 5 mg/kg per day), dFMGEN group (dFMGEN 5 mg/kg per day), model control group (the same amount of vehicle solvent), and the normal control group; all feedings administered via intragastric administration. We demonstrated that dFMGEN (1) attenuated the development of atherosclerosis, (2) reduced serum total cholesterol and low-density lipoprotein cholesterol concentrations, (3) decreased lipid peroxidation in the rabbit atherosclerosis model, and (4) increased smooth muscle cell and collagen content in atheroma of thoracic aortas. These results provide an experimental foundation for dFMGEN's potential effects in preventing and treating atherosclerosis, acute coronary syndromes, and potentially ischemia-reperfusion injury during acute myocardial infarction and cerebral infarction.


Asunto(s)
Aterosclerosis/tratamiento farmacológico , Endotelio Vascular/efectos de los fármacos , Genisteína/análogos & derivados , Fitoestrógenos/uso terapéutico , Animales , Aorta Abdominal/efectos de los fármacos , Aorta Abdominal/metabolismo , Aorta Abdominal/patología , Aorta Torácica/efectos de los fármacos , Aorta Torácica/metabolismo , Aorta Torácica/patología , Aterosclerosis/sangre , Aterosclerosis/metabolismo , Aterosclerosis/patología , Colesterol/sangre , Colágeno/metabolismo , Modelos Animales de Enfermedad , Endotelio Vascular/metabolismo , Endotelio Vascular/patología , Genisteína/administración & dosificación , Genisteína/uso terapéutico , Peroxidación de Lípido/efectos de los fármacos , Lipoproteínas LDL/sangre , Masculino , Fitoestrógenos/administración & dosificación , Conejos
20.
Clin Exp Pharmacol Physiol ; 36(12): e90-5, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19793105

RESUMEN

1. Genistein is known to protect the vascular endothelium. However, genistein exhibits poor bioavailability, which limits its use in the treatment of cardiovascular diseases. 7-Difluoromethyl-5,4'-dimethoxygenistein (dFMGEN), prepared by the difluoromethylation and alkylation of genistein, is a new active chemical entity. The protective effects of dFMGEN against vascular endothelial injury caused by oxidative stress were investigated in the present study. 2. Human umbilical vein endothelial cells were treated with either genistein (10 micromol/L) or various concentrations of dFMGEN (0.1, 0.3, 1, 3 and 10 micromol/L) for 30 min before exposure to 1 mmol/L H(2)O(2) for 24 h. The generation of reactive oxygen species (ROS) was assessed by fluorescence flow cytometry, the release of lactate dehydrogenase (LDH) was examined by biochemical assay, cell viability was measured by the 3-(4,5-dimethyl-2 thiazoyl)-2,5-diphenyl-2H-tetrazolium bromide assay, cell apoptosis was detected by flow cytometry and the expression of caspase 3 was examined by western blot analysis. 3. Pretreatment with 0.1, 0.3, 1, 3 and 10 micromol/L dFMGEN decreased the generation of ROS and the release of LDH in H(2)O(2)-exposed vascular endothelial cells, enhanced cell viability in a concentration-dependent manner over the concentration range 0.1-10 micromol/L, suppressed H(2)O(2)-induced apoptosis of vascular endothelial cells and downregulated the expression of caspase 3. The protective effect of 10 micromol/L dFMGEN against oxidative stress-induced endothelial injury was stronger than that of 10 micromol/L genistein. 4. The results of the present study suggest that dFMGEN can protect against vascular endothelial injury caused by oxidative stress.


Asunto(s)
Cardiotónicos/farmacología , Células Endoteliales/efectos de los fármacos , Genisteína/análogos & derivados , Estrés Oxidativo/efectos de los fármacos , Enfermedades Vasculares/prevención & control , Apoptosis/efectos de los fármacos , Cardiotónicos/uso terapéutico , Caspasa 3/metabolismo , Línea Celular , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Células Endoteliales/metabolismo , Femenino , Genisteína/farmacología , Genisteína/uso terapéutico , Humanos , Peróxido de Hidrógeno/farmacología , L-Lactato Deshidrogenasa/metabolismo , Especies Reactivas de Oxígeno/metabolismo
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