首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
Success of Cyrtobagous salviniae Calder & Sands (Coleoptera: Curculionidae) for biological control of Salvinia molesta D. S. Mitchell in temperate regions has been less reliable than in tropical and subtropical regions and this difference is presumed to be due to greater winter mortality. We measured the cold tolerance of C. salviniae by comparing chill coma recovery time and survival of adults after exposure to freezing conditions among four geographic populations collected from Florida, Louisiana, Texas and Australia. Effects of winter temperature acclimation on low temperature oviposition also were determined. The Australian population was more cold tolerant than the three US populations. No oviposition by C. salviniae was observed at a water temperature of 17 °C and the oviposition rate at 19 °C was less than at 21, 23 and 25 °C. We suggest that introduction of cold tolerant strains of C. salviniae could increase its effectiveness in temperate regions of the US.  相似文献   

2.
Two new pterosin glycosides, (2S,3S)-pterosin C 3-O-β-d-(4′-(E)-caffeoyl)-glucopyranoside (1) and (2S,3S)-pterosin C 3-O-β-d-(6′-(E)-p-coumaroyl)-glucopyranoside (2), were isolated from Pteris multifida (Pteridaceae) roots along with ten known pterosin compounds (312). The chemical structures of the isolated compounds were elucidated by extensive analysis of the 1D, 2D NMR, HRESIMS, and CD spectroscopic data. The cytotoxicities of 112 against HCT116 human colorectal cancer cell line were evaluated. Among the isolates, compound 1 showed moderate antiproliferative activity in HCT116 cells with an IC50 value of 8.0 ± 1.7 μM. Additionally, 1 induced the upregulation of the caspase-9 and procaspase-9 levels in Western blots and increased the annexin V/propidium iodide (PI)-positive cell population in flow cytometry.  相似文献   

3.
水朝阳旋覆花中新的细胞毒活性麝香草酚类化合物   总被引:2,自引:0,他引:2  
从水朝阳旋覆花(1nula heliamhus-aquatica)的95%乙醇提取物中分离得到4个麝香草酚类化合物,其中化合物1为新化合物。它们的化学结构通过波谱方法鉴定为:8-hydroxy-9,10-dioxyisopropylidene-thymol(1),10-hydroxy-8,9-dioxyisopropylidene—thymol(2),8-hydroxy-9,10-diisobutyryloxy—thymol(3)和8,10-dihydroxy-9-isobutyryloxy—thymol(4)。肿瘤细胞毒试验结果表明它们在6种肿瘤细胞株上(K562,HT-29,SGC-7901,DU145,MDA-MB-231,U251)显示一定的细胞毒活性,其中化合物2活性最强,它的IC50值为4.20~33.12umol/L。具有细胞毒活性的麝香草酚类化合物是首次在该种植物中发现。  相似文献   

4.
5.
6.
Two compounds, 3′-deoxyinosine and cordycepin, were isolated from Bombyx mori inoculated with Cordyceps militaris. In the bioassay examining cytotoxicity against cancer cells, both compounds showed toxicity against A549, PANC-1, and MCF-7 cancer cells.  相似文献   

7.
(R)- and (S)-Goniothalamin (1) and analogues 2-9 were efficiently prepared in high overall yield and enantiomeric purity, and their cytotoxic activities were evaluated against eight human cancer cell lines. A structure-activity relationship study (SAR) allowed us to establish the relevant structural features for the cytotoxic activity of goniothalamin analogues. In addition, we have identified non-natural form of goniothalamin (S)-1 and analogue 5 as the highest and more selective cytotoxic compounds against kidney cancer cell growth (786-0) with IC50 = 4 and 5 nM, respectively, and compound 8 (IC50 = 4 nM) as the more potent against breast cancer cells with resistance phenotype for adryamycin (NCI.ADR).  相似文献   

8.
Marine mussels illustrate a stunning variability in shape and color. Such variability, added to the scarcity of reliable morphological characters for their identification, can mislead recognition prompting the assignation of specimens of a single species to different ones or incorporate specimens belonging to different taxa into a single one. DNA barcoding is widely used for species identification; however, as this method relies on the previous morphological identification of the specimens, some of the DNA sequences stored in DNA databases are incorrectly assigned to a given species. In view of this uncertainty, further criteria beyond morphological characters and DNA sequences in databases are required to more reliably and accurately identify marine mussels. In this work we mapped ribosomal RNA and histone gene clusters to chromosomes of four species of marine mussels and compared them with those from another eight marine mussel taxa. Specimens of these twelve taxa were also DNA barcoded. Our results clearly demonstrated that the chromosomal analysis of marine mussels could shed light on their identification and, therefore, solve contradictions posed by morphological and molecular data.  相似文献   

9.
A chemical study focusing on the N-containing constituents of Hymenocallis littoralis was carried out, leading to the isolation of two new alkaloidal flavonoids (12) and five known alkaloids (3-7). Structures of the isolated compounds were established mainly by spectroscopic techniques, including NMR spectroscopy and mass spectrometry as well as the CD experiment. These compounds were subjected to the in vitro cytotoxicity assays using Hep3B cells, and among them only the known pancratistatine (3) and lycorine (5) could significantly inhibit the Hep3B cell proliferation.  相似文献   

10.
In order to explore the apoptotic and anti-tumor activities of metallo-salens, we synthesized several Mn(III)-salen derivatives (compds. 1-9) and analyzed their effects on cultured human cancer and non-cancer cells. Our results demonstrated that Mn(III)-salen derivatives affect cell viability, induce nuclear condensation and fragmentation in breast cancer cells (MCF7). Mn(III)-salen derivatives also induced caspase-3/7 activation and release of cytochrome-c from the mitochondria to cytosol suggesting that Mn(III)-salen derivatives induce apoptosis in human cells via mitochondrial pathway. Importantly, the nature of the substituent and the bridging spacer between diimino groups on the salen ligand play critical roles in determining the apoptotic activities of Mn(III)-salen derivatives. The IC50 values for the active Mn(III)-salen derivatives lie within the range of 11-40 μM in MCF7 cells. Most importantly, several Mn(III)-salen derivatives showed preferential cytotoxicity (2- to 5-fold) toward malignant breast cells (MCF7) over a non-malignant breast epithelial cell line (MCF10). Notably, the level of cytotoxicity and selectivity of the Mn(III)-salen derivatives towards MCF7 and MCF10 cells are very similar to cisplatin which indicate that Mn(III)-salens are potential novel anti-tumor agent.  相似文献   

11.
Feral goats (Capra hircus) are ubiquitous across much of Australia's arid and semi-arid rangelands, where they compete with domestic stock, contribute to grazing pressure on fragile ecosystems, and have been implicated in the decline of several native marsupial herbivores. Understanding the success of feral goats in Australia may provide insights into management strategies for this and other invasive herbivores. It has been suggested that frugal use of energy and water contributes to the success of feral goats in Australia, but data on the energy and water use of free-ranging animals are lacking. We measured the field metabolic rate and water turnover rate of pregnant and non-pregnant feral goats in an Australian rangeland during late summer (dry season). Field metabolic rate of pregnant goats (601 ± 37 kJ kg− 0.73 d− 1) was 1.3 times that of non-pregnant goats (456 ± 24 kJ kg− 0.73 d− 1). The water turnover rate of pregnant goats (228 ± 18 mL kg− 0.79 d− 1) was also 1.3 times that of non-pregnant goats (173 ± 18 kg− 0.79 d− 1), but the difference was not significant (P = 0.07). There was no significant difference in estimated dry matter digestibility between pregnant and non-pregnant goats (mean ca. 58%), blood or urine osmolality, or urine electrolyte concentrations, indicating they were probably eating similar diets and were able to maintain osmohomeostasis. Overall, the metabolic and hygric physiology of non-pregnant goats conformed statistically to the predictions for non-marine, non-reproductive placental mammals according to both conventional and phylogenetically independent analyses. That was despite the field metabolic rate and estimated dry matter intake of non-pregnant goats being only 60% of the predicted level. We suggest that general allometric analyses predict the range of adaptive possibilities for mammals, but that specific adaptations, as present in goats, result in ecologically significant departures from the average allometric curve. In the case of goats in the arid Australian rangelands, predictions from the allometric regression would overestimate their grazing pressure by about 40% with implications for the predicted impact on their local ecology.  相似文献   

12.
South American tomato pinworm, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is a devastating invasive global insect pest of tomato, Solanum lycopersicum (Solanaceae). In nature, pests face multiple overlapping environmental stressors, which may significantly influence survival. To cope with rapidly changing environments, insects often employ a suite of mechanisms at both acute and chronic time-scales, thereby improving fitness at sub-optimal thermal environments. For T. absoluta, physiological responses to transient thermal variability remain under explored. Moreso, environmental effects and physiological responses may differ across insect life stages and this can have implications for population dynamics. Against this background, we investigated short and long term plastic responses to temperature of T. absoluta larvae (4th instar) and adults (24–48 h old) from field populations. We measured traits of temperature tolerance vis critical thermal limits [critical thermal minima (CTmin) and maxima (CTmax)], heat knockdown time (HKDT), chill coma recovery time (CCRT) and supercooling points (SCP). Our results showed that at the larval stage, Rapid Cold Hardening (RCH) significantly improved CTmin and HKDT but impaired SCP and CCRT. Heat hardening in larvae impaired CTmin, CCRT, SCP, CTmax but not HKDT. In adults, both heat and cold hardening generally impaired CTmin and CTmax, but had no effects on HKDT, SCP and CCRT. Low temperature acclimation significantly improved CTmin and HKDT while marginally compromising CCRT and CTmax, whereas high temperature acclimation had no significant effects on any traits except for HKDT in larvae. Similarly, low and high temperature acclimation had no effects on CTmin, SCPs and CTmax, while high temperature acclimation significantly compromised adult CCRT. Our results show that larvae are more thermally plastic than adults and can shift their thermal tolerance in short and long timescales. The larval plasticity reported here could be advantageous in new envirnments, suggesting an asymmetrical ecological role of larva relative to adults in facilitating T. absoluta invasion.  相似文献   

13.
Curcuma zedoaria rhizome (Zingiberaceae) is a well-known traditional medicinal plant used in Ayurvedic and traditional Chinese medicine to treat various cancers. This study aimed to identify the cytotoxic components from C. zedoaria rhizomes that act against gastric cancer, which is the third leading cause of death from cancer worldwide because the MeOH extract of C. zedoaria rhizome was found to show a cytotoxic effect against gastric cancer AGS cells. Repeated column chromatography and semi-preparative HPLC purification were used to separate the components from the C. zedoaria MeOH extract. Two new sesquiterpenes, curcumenol-9,10-epoxide (1) and curcuzedoalide B (2), and 12 known related sesquiterpenes (3–14) were isolated from the C. zedoaria MeOH extract. The structures of new compounds were determined by 1D and 2D NMR spectroscopic experiments and HR-ESIMS, and quantum chemical ECD calculations. The cytotoxic effects of the isolated compounds were measured in human gastric cancer AGS cells using an MTT cell viability assay. Compounds 9, 10, and 12 exhibited cytotoxic effects against gastric cancer AGS cells, with IC50 values in the range of 212–392 μM. These findings provide further experimental scientific evidence to support the traditional use of C. zedoaria rhizomes for the treatment of cancer. Curcumenol (9), 4,8-dioxo-6β-methoxy-7α,11-epoxycarabrane (10), and zedoarofuran (12) were identified as the main cytotoxic components in C. zedoaria rhizomes.  相似文献   

14.
Fuke Y  Haga Y  Ono H  Nomura T  Ryoyama K 《Cytotechnology》1997,25(1-3):197-203
Synthetic 4-methylsulfinylhexyl isothiocyanate (MITC)(a potent inducer of phase 2 detoxification enzymes from broccoli) and 6-MITC(a potent anti-proliferative principal from wasabi) slightly inhibited the induction of mouse skin tumor in a two-stage process of carcinogenesis (initiator, 9,10-dimethyl-1,2-benzanthracene; promotor,12-o-tetradecanoylphorbol-13-acetate), but the effect was not significant. Both compounds, however, significantly inhibited the mutation of skin resulting from topical applications of the carcinogens. When a murine hepatoma cell line, Hepa 1c1c7, was treated with 2-,4-,6- and 8-MITCs, they augmented the induction of its quinone reductase, one of the phase 2 detoxification enzymes in a concentration dependent manner, and the 4- and 6-MITCs were much more potent on the reduction of the enzyme than the 2- and 8-MITCs. All 2-, 4-, 6- and 8-MITCs suppressed the growth of murine tumor cells, their suppressive activities being proportional to the length of their methyl residue. They were also cytotoxic to mouse peritoneal exudate macrophages which were not proliferating in vitro, indicating that the cellular targets of isothiocyanate may not be dependent upon the cell cycle. In addition, all the 2-, 4-, 6- and 8-MITCs inhibited the production of nitric oxide (a potent radical carcinogen) by peritoneal macrophages. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

15.
Extraction of Tripterygium doianum (Celastraceae) afforded five new diterpenoids and 11 known diterpenoids belonging to the ent-kaurane and abietane families. Their structures were established based on spectroscopic studies. The isolated compounds showed moderate cytotoxicity against human tumor cell assays.  相似文献   

16.
《Journal of Asia》2020,23(1):219-223
The bluegrass webworm moth Parapediasia teterrella (Zincken, 1821) is a notorious pest that is native to North America. However, it has invaded East Asia and has caused serious economic losses in China and Japan. The objective of this paper is to analyse the potential geographic distribution of P. teterrella in East Asia with MaxEnt, using predictor variables related to temperature and precipitation. It is suggested that this species has potential to establish in Southeast China, most areas of Jeollanam-do, eastern coastal region of South Korea, and most areas of Japan. Furthermore, we applied the Jackknife test to evaluate the significance of climatic variables in modelling the potential distribution of P. teterrella. The result indicates that annual mean temperature (Bio1), mean temperature of the coldest quarter (Bio11) and precipitation of the coldest quarter (Bio19) mainly affect its geographical distribution. A map showing the potential distribution of P. teterrella in East Asia is provided, and morphological diagnosis of the species is also given.  相似文献   

17.
The biological evaluation of new Ru(II) complexes carrying dmoPTA (dmoPTA = 3,7-dimethyl-1,3,7-triaza-5-phosphabicyclo[3.3.1]nonane) ligands is reported. The results on the biological activity revealed that the organometallic complexes are active against all cell lines with GI50 values in the range 1.1-2.6 μM. When compared to the standard anticancer drug cisplatin, the bimetallic Ru(II) complexes showed a greater activity profile. The cell cycle analysis revealed that the new compounds induced arrest in G1 phase. Contrary to cisplatin, these Ru(II) complexes do not interact with DNA. This result suggests that DNA might not be the key pharmacological target.  相似文献   

18.
Raccoons are American carnivores, considered invasive across several countries worldwide, especially in Europe. In the Iberian Peninsula, previous studies on raccoons documented several breeding populations in Spain a decade ago and only two confirmed records from isolated individuals in Portugal. Given the need for updating its Iberian distribution and identifying suitable areas with higher invasion risk, we compiled presence records from established breeding populations and isolated individuals. By using a Maxent approach based on breeding records, we forecasted the suitable habitats in Iberia with higher invasion risk for raccoons and identified the related environmental drivers. Overall, we collected 1039 records of raccoon presence throughout the Iberian Peninsula, including 980 records from established breeding populations. Their origin is probably linked to escapes from captivity. Climatic conditions, linked to both drier and wetter environments, and proximity to water bodies were the main predictors of suitable areas for raccoon’s expansion from the currently established breeding nuclei in Iberia. The forecasted high probability areas showed a wide, but fragmented distribution concentrated on four main areas: central, central-north, central-east, and north-west Iberia. NW Portugal seems to be the area with higher invasion risk in the country, although field surveys showed no evidence of raccoon presence yet. However, there are several records in Spain near the Portuguese border, comprising isolated individuals and breeding populations. Therefore, it is crucial to ensure regular monitoring of areas with high invasion risk, particularly those near facilities with captive raccoons that often act as a source of feral individuals, to assure early detection and effective control for the expansion of this invasive carnivore.  相似文献   

19.
《Journal of Asia》2020,23(2):442-444
The Australian tortoise beetle Trachymela sloanei (Coleoptera: Chrysomelidae: Chrysomelinae), an invasive pest of several species of Eucalyptus has been reported for the first time in Asia. It was first detected in Shenzhen, China where it has become established. Currently, T. sloanei is not a destructive forest pest in Shenzhen. Pupae and adults were frequently found infected by an unknown fungus.  相似文献   

20.
Abstract

Floating ferns of the genus Salvinia have great potential for phytoremediation of heavy metals. To date, the effect of essential metals on the accumulation and transport of toxic metals by aquatic ferns has not been suitably established. The aim of this study was to compare the ability of floating leaves of Salvinia minima and Salvinia rotundifolia species to accumulate Cr from Cr(VI solutions containing very low (0.02?mg L?1) and low (5?mg L?1) Zn concentrations. After 7-day metal-exposure period, results showed that Zn increased Cr accumulation in S. minima leaves whereas in S. rotundifolia decreased significantly. Contrarily Zn accumulation did not show great differences between species. This fact may indicate that Zn interfere Cr(VI) uptake by S. rotundifolia. Bioconcentration factor (BCF) and translocation factor (TF) were affected differently by Zn in both Salvinia species. Membrane stability index (MSI) of both Salvinia species was decreased significantly by 5?mg L?1 Zn concentration. Zn ions also increased hydrogen peroxide accumulation in fronds of Salvinia species. Total thiols (TT), non-protein thiols (NPT) and protein-bound thiols (PBT) were differentially affected by Cr(VI) and Zn ions. This study provides evidences on the involvement of different mechanisms against Cr(VI)/Zn toxicity in S. minima and S rotundifolia species.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号