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161.
The symbiotic dinoflagellate microalgae of corals (Symbiodinium spp.) contain high concentrations of dimethylsulfoniopropionate (DMSP), a multifunctional metabolite commonly found in many
species of marine algae and dinoflagellates. A photoprotective antioxidant function for DMSP and its breakdown products has
often been inferred in algae, but its role(s) in the coral–algal symbiosis remains elusive. To examine potential correlations
between environmental and physiological parameters and DMSP, total DMSP (DMSPt, from the host coral and zooxanthellae), particulate DMSP (DMSPp, from the zooxanthellae only), coral surface area, and total protein, as well as zooxanthellae density, chlorophyll concentration,
cell volume and genotype (i.e., clade) were measured in five coral species from the Diploria-Montastraea-Porites species complex in Bermuda along a depth gradient of 4, 12, 18, and 24 m. DMSPt concentrations were consistently greater than DMSPp concentrations in all species suggesting the possible translocation of DMSP from symbiont to host. D. labyrinthiformis was notably different from the other corals examined, showing DMSPp and DMSPt increases (per coral surface area or tissue biomass) with increasing water depth. However, overall, there were no consistent
depth-related patterns in DMSPp and DMSPt concentrations. Further research, investigating dimethylsulfide (DMS), dimethylsulfoxide, and acrylate levels and DMSP-lyase
activity in correlation with other biomarker endpoints that have been shown to be depth (i.e., temperature and light) responsive
are needed to substantiate the significance of these findings. 相似文献
162.
A. P. Krueger A. E. Strubbe M. G. Yost E. J. Reed 《International journal of biometeorology》1978,22(3):202-212
Early growth of barley seedlings supplied with ion-depleted air in a controlled microenvironment was used as the criterion of physiological action in experiments designed to separate electrical field and air ion effects. The essential element in this work was the fact that3H foils, functioning as bias electrodes at applied voltages of 67.5-955 V and providing field strengths of 4.6 V/cm to 90 V/cm will produce 2.7×104–1.7×105 small air ions/cm3 — concentrations sufficient to yield a statistically valid increase in growth rate. In contrast, seedlings exposed to equivalent electrical fields in ion-depleted air exhibited no increase in rate of growth. These results indicate that this particular physiological response is produced by small negative air ions and is not dependent on the accompanying electrical fields. 相似文献
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165.
Plasmid DNA minipreps are fundamental techniques in molecular biology. Current plasmid DNA minipreps use alkali and the anionic detergent SDS in a three-solution format. In addition, alkali minipreps usually require additional column-based purification steps and cannot isolate other extra-chromosomal elements, such as bacteriophages. Non-ionic detergents (NIDs) have been used occasionally as components of multiple-solution plasmid DNA minipreps, but a one-step approach has not been developed. Here, we have established a one-tube, one-solution NID plasmid DNA miniprep, and we show that this approach also isolates bacteriophage lambda particles. NID minipreps are more time-efficient than alkali minipreps, and NID plasmid DNA performs better than alkali DNA in many downstream applications. In fact, NID crude lysate DNA is sufficiently pure to be used in digestion and sequencing reactions. Microscopic analysis showed that the NID procedure fragments E. coli cells into small protoplast-like components, which may, at least in part, explain the effectiveness of this approach. This work demonstrates that one-step NID minipreps are a robust method to generate high quality plasmid DNA, and NID approaches can also isolate bacteriophage lambda particles, outperforming current standard alkali-based minipreps. 相似文献
166.
Michael B Coulthart Gerard H Jansen Elina Olsen Deborah L Godal Tim Connolly Bernard CK Choi Zheng Wang Neil R Cashman 《BMC neurology》2011,11(1):133
Background
To better characterize the value of cerebrospinal fluid (CSF) proteins as diagnostic markers in a clinical population of subacute encephalopathy patients with relatively low prevalence of sporadic Creutzfeldt-Jakob disease (sCJD), we studied the diagnostic accuracies of several such markers (14-3-3, tau and S100B) in 1000 prospectively and sequentially recruited Canadian patients with clinically suspected sCJD. 相似文献167.
Stanley CK Cheung Li-zhong Liu Lin-lin Lan Qiao-quan Liu Samuel SM Sun Juliana CN Chan Peter CY Tong 《BMC biotechnology》2011,11(1):37
Background
Human insulin-like growth factor-I (hIGF-I) is a growth factor which is highly resemble to insulin. It is essential for cell proliferation and has been proposed for treatment of various endocrine-associated diseases including growth hormone insensitivity syndrome and diabetes mellitus. In the present study, an efficient plant expression system was developed to produce biologically active recombinant hIGF-I (rhIGF-I) in transgenic rice grains. 相似文献168.
Hyun Yang Tae-Hee Kim Hae-Hyeog Lee Kyung-Chul Choi Yeon-pyo Hong Peter CK Leung Eui-Bae Jeung 《Reproductive biology and endocrinology : RB&E》2011,9(1):28
Human endometrium resists embryo implantation except during the 'window of receptivity'. A change in endometrial gene expression
is required for the development of receptivity. Uterine calbindin-D28k (CaBP-28k) is involved in the regulation of endometrial
receptivity by intracellular Ca2+. Currently, this protein is known to be mainly expressed in brain, kidneys, and pancreas,
but potential role(s) of CaBP-28k in the human uterus during the menstrual cycle remain to be clarified. Thus, in this study
we demonstrated the expression of CaBP-28k in the human endometrium in distinct menstrual phases. During the human menstrual
cycle, uterine expression levels of CaBP-28k mRNA and protein increased in the proliferative phase and fluctuated in these
tissues, compared with that observed in other phases. We assessed the effects of two sex-steroid hormones, 17beta-estradiol
(E2) and progesterone (P4), on the expression of CaBP-28k in Ishikawa cells. A significant increase in the expression of CaBP-28k
mRNA was observed at the concentrations of E2 (10(-9 to -7) M). In addition, spatial expression of CaBP-28k protein was detected
by immunohistochemistry. CaBP-28k was abundantly localized in the cytoplasm of the luminal and glandular epithelial cells
during the proliferative phases (early-, mid-, late-) and early-secretory phase of menstrual cycle. Taken together, these
results indicate that CaBP-28k, a uterine calcium binding protein, is abundantly expressed in the human endometrium, suggesting
that uterine expression of CaBP-28k may be involved in reproductive function during the human menstrual cycle. 相似文献
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170.