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11.
Thomas A. Kursar Catherina C. Caballero-George Todd L. Capson Luis Cubilla-Rios William H. Gerwick Maria V. Heller Alicia Ibañez Roger G. Linington Kerry L. McPhail Eduardo Ortega-Barría Luz I. Romero P. D. Coley 《Biodiversity and Conservation》2007,16(10):2789-2800
The limited international resources for economic aid and conservation can only mitigate poverty and losses of biodiversity.
Hence, developing nations must establish the capacity to resolve their problems. Additionally, policy-makers and donors need
to obtain scientific input on issues such as global change and ecosystem services. We propose that for nations rich in biodiversity,
ecosystem services derived from bioprospecting, or drug discovery, could contribute to economic development. In the case where
unstudied samples are shipped abroad for research, the chances of obtaining royalties are infinitesimally small. Therefore
developing nations will only realize benefits from bioprospecting through in-country research on their own biodiversity. Policy-makers
and donors have failed to appreciate the value of this approach. In order to provide an example of the inherent links between
conservation and sustainable economic development, we initiated a drug discovery effort in Panama that emphasizes local benefit.
As much of the drug discovery process as possible is conducted in Panamanian laboratories, providing jobs dependent on intact
biodiversity and enhancing local research and training. In short, research, plus the spin-offs from research, provide immediate
and long-lasting benefits to Panama. The connection between conservation and development has been highlighted in publicity
about the project in Panama’s urban media. This provides a constructive alternative to the perception the among the urban
populace that economic development inevitably competes with conservation. In summary, our program uses biodiversity to promote
human health as well as to support research capacity, economic development and conservation within Panama. The program provides
an example of the widely recognized but little developed concept of bioprospecting research as an ecosystem service. 相似文献
12.
13.
Chia-Chun Yu Shih-Ping Liu Jui-Ling Hsu John TA Hsu Konstantin V Kudryavtsev Jih-Hwa Guh 《Journal of biomedical science》2015,22(1)
Background
Hormone-refractory prostate cancer (HRPC), which is resistant to hormone therapy, is a major obstacle in clinical treatment. An approach to inhibit HRPC growth and ultimately to kill cancers is highly demanded.Results
KUD773 induced the anti-proliferative effect and subsequent apoptosis in PC-3 and DU-145 (two HRPC cell lines); whereas, it showed less active in normal prostate cells. Further examination showed that KUD773 inhibited tubulin polymerization and induced an increase of mitotic phosphoproteins and polo-like kinase 1 (PLK1) phosphorylation, indicating a mitotic arrest of the cell cycle through an anti-tubulin action. The kinase assay demonstrated that KUD773 inhibited Aurora A activity. KUD773 induced an increase of Cdk1 phosphorylation at Thr161 (a stimulatory phosphorylation site) and a decrease of phosphorylation at Tyr15 (an inhibitory phosphorylation site), suggesting the activation of Cdk1. The data were substantiated by an up-regulation of cyclin B1 (a Cdk1 partner). Furthermore, KUD773 induced the phosphorylation and subsequent down-regulation of Bcl-2 and activation of caspase cascades.Conclusions
The data suggest that KUD773 induces apoptotic signaling in a sequential manner. It inhibits tubulin polymerization associated with an anti-Aurora A activity, leading to Cdk1 activation and mitotic arrest of the cell cycle that in turn induces Bcl-2 degradation and a subsequent caspase activation in HRPCs. 相似文献14.
铅锌镉联合染毒及营养干预对大鼠血液系统的影响研究 总被引:1,自引:0,他引:1
目的:了解铅锌镉联合染毒对大鼠血液系统的影响及营养干预对其损伤的修复作用。方法:选择SPF级初断乳Wistar大鼠72只,随机分为对照组、染毒组和干预组,分别采用生理盐水、铅锌镉联合染毒液及染毒后以营养干预液灌胃28天和56天之后,检测其血液系统中五元素和血细胞的指标。结果:染毒组较对照组大鼠血铜、血锌含量高,血钙含量低于对照组,差异均有统计学意义(P<0.05);染毒组血铜含量高于干预组,血钙含量低于干预组,差异均有统计学意义(P<0.05);干预组红细胞(RBC)计数、血红蛋白(Hb)、血细胞比容(HCT)均高于染毒组,差异均有统计学意义(P<0.05);对照组白细胞(WBC)计数高于染毒组、干预组,差异均有统计学意义(P<0.05)。结论:铅镉对大鼠血铜、血钙、血锌水平有影响;综合营养干预对重金属元素造成的血液系统损伤有明显的拮抗作用,对血液系统有一定的保护及修复作用。 相似文献
15.
Michael D Kennedy Mark J Haykowsky Carol A Boliek Ben TA Esch Jessica M Scott Darren ER Warburton 《Dynamic medicine : DM》2006,5(1):8
Background
Near infrared spectroscopy (NIRS) is used to assess muscle oxygenation (MO) within skeletal muscle at rest and during aerobic exercise. Previous investigations have used a single probe placement to measure MO during various forms of exercise. However, regional MO differences have been shown to exist within the same muscle which suggests that different areas of the same muscle may have divergent MO. Thus, the aim of this study was to examine whether regional differences in MO exist within the same muscle during different types of incremental (rest, 25, 50, 75, 100 % of maximum) exercise (1 leg knee extension (KE), 2 leg KE, or cycling).Methods
Nineteen healthy active males (Mean ± SD: Age 27 ± 4 yrs; VO2max: 55 ± 11 mL/kg/min) performed incremental exercise to fatigue using each mode of exercise. NIRS probes were placed on the distal and proximal portion of right leg vastus lateralis (VL). Results were analyzed with a 3-way mixed model ANOVA (probe × intensity × mode).Results
Differences in MO exist within the VL for each mode of exercise, however these differences were not consistent for each level of intensity. Comparison of MO revealed that the distal region of VL was significantly lower throughout KE exercise (1 leg KE proximal MO – distal MO = 9.9 %; 2 leg KE proximal MO – distal MO = 13 %). In contrast, the difference in MO between proximal and distal regions of VL was smaller in cycling and was not significantly different at heavy workloads (75 and 100 % of maximum).Conclusion
MO is different within the same muscle and the pattern of the difference will change depending on the mode and intensity of exercise. Future investigations should limit conclusions on MO to the area under assessment as well as the type and intensity of exercise employed.16.
目的:探讨铅锌联合染毒对乳鼠颅骨成骨细胞增殖分化的影响。方法:分离并培养原代成骨细胞,加入不同浓度铅、锌培养48h,检测其对成骨细胞增殖的作用;用碱性磷酸酶试剂盒检测ALP活力。结果:在染铅48h后,当铅浓度≥10μmol/L时,细胞增殖功能下降(P<0.05);加锌干预48h后,铅+锌组细胞增殖功能均高于各自单独染铅组,其中铅(1μmol/L、10μmol/L)+锌(50μmol/L)组、铅(10)+锌(100)组与对照组间的差异具有统计学意义(P<0.05)。铅干预48h后,100μmol/L铅组的ALP活力显著下(P<0.05),给予锌干预的铅锌联合染毒组,各组ALP活力均有增加,其中铅(1μmol/L、10μmol/L)+锌(50μmol/L)组ALP活力均高于对照组,而铅(100μmol/L)+锌(50μmol/L)组ALP活力低于对照组,差异均有统计学意义(P<0.05)。结论:铅对成骨细胞有毒性作用,影响其增殖和分化功能;50μmol/L锌在一定程度上可以拮抗铅对成骨细胞增殖和分化功能的损伤,且对ALP活力的作用更显著,为铅中毒骨病的防治提供一定的科学依据。 相似文献
17.
Lutein epoxide cycle, light harvesting and photoprotection in species of the tropical tree genus Inga 总被引:2,自引:0,他引:2
Matsubara S Krause GH Seltmann M Virgo A Kursar TA Jahns P Winter K 《Plant, cell & environment》2008,31(4):548-561
Dynamics and possible function of the lutein epoxide (Lx) cycle, that is, the reversible conversion of Lx to lutein (L) in the light-harvesting antennae, were investigated in leaves of tropical tree species. Photosynthetic pigments were quantified in nine Inga species and species from three other genera. In Inga , Lx levels were high in shade leaves (mostly above 20 mmol mol−1 chlorophyll) and low in sun leaves. In Virola surinamensis , both sun and shade leaves exhibited very high Lx contents (about 60 mmol mol−1 chlorophyll). In Inga marginata grown under high irradiance, Lx slowly accumulated within several days upon transfer to deep shade. When shade leaves of I. marginata were briefly exposed to the sunlight, both violaxanthin and Lx were quickly de-epoxidized. Subsequently, overnight recovery occurred only for violaxanthin, not for Lx. In such leaves, containing reduced levels of Lx and increased levels of L, chlorophyll fluorescence induction showed significantly slower reduction of the photosystem II electron acceptor, Q A , and faster formation as well as a higher level of non-photochemical quenching. The results indicate that slow Lx accumulation in Inga leaves may improve light harvesting under limiting light, while quick de-epoxidation of Lx to L in response to excess light may enhance photoprotection. 相似文献
18.
Morphology and coexistence of congeneric ectoparasite species: reinforcement of reproductive isolation? 总被引:1,自引:0,他引:1
ANDREA IMKOVÁ MARKÉTA ONDRAKOVÁ MILAN GELNAR SERGE MORAND 《Biological journal of the Linnean Society. Linnean Society of London》2002,76(1):125-135
Assuming that differences or similarities in morphology among congeneric parasite species living in the same habitat are not a random pattern, several hypotheses explaining morphological differences were tested: (i) reproductive isolation, (ii) niche restriction resulting from competition, and (iii) niche specialization. Congeneric monogenean (platyhelminth) ectoparasites parasitizing the gills of one host species were used as an ecological model. Morphometric distances of the attachment organ and morphometric distances of the copulatory organ between species pairs were calculated, Levin's niche size and Renkonen niche overlap indices were applied. Our results support the prediction that the function of niche segregation is to achieve reproductive isolation of related species in order to prevent hybridization (reinforcement of reproductive barriers). Parasite species living in the same niche differ greatly in the size of copulatory organ. Moreover, species coexistence is facilitated by an increase in morphometric distances of copulatory organ and niche centre distances. Our results also show that species living in overlapping niches have similar attachment organs, which supports the prediction that morphologically similar species have the same ecological requirements within one host and suggests small effects of interspecific competition for the evolution of morphological diversity of attachment organs. Specialist adaptations also seem to facilitate species coexistence and affect the niche distribution within host species. Parasite species that can colonize more than one host species, i.e. generalists, occupy more distant niches within host species than strictly host-specific parasites. © 2002 The Linnean Society of London, Biological Journal of the Linnean Society , 2002, 76, 125–135. 相似文献
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20.
Distribution of amiloride-sensitive sodium channels in the oral cavity of the hamster 总被引:3,自引:3,他引:0
The distribution of amiloride-sensitive sodium channels (ASSCs) in taste
buds isolated from the oral cavity of hamsters was assessed by patch clamp
recording. In contrast to the case for rats, taste cells from the
fungiform, foliate and vallate papillae and from the soft palate all
contain functional ASSCs. The differential distribution of ASSCs between
the hamster and the rat may be important for understanding the physiology
underlying the differing behavioral responses of these species to sodium
salts.
相似文献