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961.
Pseudomonas putida E41 was isolated from oil-contaminated soil and showed its ability to grow on ethyl-benzene as the sole carbon and energy
source. Moreover, P. putida E41 show the activity of biodegradation of ethylbenzene in the batch culture. E41 showed high efficiency of biodegradation
of ethylbenzene with the optimum conditions (a cell concentration of 0.1 g wet cell weight/L, pH 7.0, 25°C, and ethylbenzene
concentration of 50 mg/L) from the results of the batch culture. The maximum degradation rate and specific growth rate (μmax) under the optimum conditions were 0.19+0.03 mg/mg-DCW (Dry Cell Weight)/h and 0.87+0.13 h−1, respectively. Benzene, toluene and ethylbenzene were degraded when these compounds were provided together; however, xylene
isomers persisted during degradation by P. putida E41. When using a bioreactor batch system with a binary culture with P. putida BJ10, which was isolated previously in our lab, the degradation rate for benzene and toluene was improved in BTE mixed medium
(each initial concentration: 50 mg/L). Almost all of the BTE was degraded within 4 h and 70–80% of m-, p-, and o-xylenes within 11 h in a BTEX mixture (initial concentration: 50 mg/L each). In summary, we found a valuable new strain of
P. putida, determined the optimal degradation conditions for this isolate and tested a mixed culture of E41 and BJ10 for its ability
to degrade a common sample of mixed contaminants containing benzene, toluene, and xylene. 相似文献
962.
NMR structural determination of large multi-domain proteins is a challenging task due to significant spectral overlap with
a particular difficulty in unambiguous identification of domain–domain interactions. Segmental labeling is a NMR strategy
that allows for isotopically labeling one domain and leaves the other domain unlabeled. This significantly simplifies spectral
overlaps and allows for quick identification of domain–domain interaction. Here, a novel segmental labeling strategy is presented
for detection of inter-domain NOEs. To identify domain–domain interactions in human apolipoprotein E (apoE), a multi-domain,
299-residues α-helical protein, on-column expressed protein ligation was utilized to generate a segmental-labeled apoE samples
in which the N-terminal (NT-) domain was 2H(99%)/15N-labeled whereas the C-terminal (CT-) domain was either 15N- or 15N/13C-labeled. 3-D 15N-edited NOESY spectra of these segmental-labeled apoE samples allow for direct observation of the inter-domain NOEs between
the backbone amide protons of the NT-domain and the aliphatic protons of the CT-domain. This straightforward approach permits
unambiguous identification of 78 inter-domain NOEs, enabling accurate definition of the relative positions of both the NT-
and the CT-domains and determination of the NMR structure of apoE. 相似文献
963.
Despite improved national censuses and “micro-demographic” studies, demographic processes and health conditions among indigenous populations in Amazonia and elsewhere in lowland Latin America are not well understood. A new source of demographic and health data has emerged in the past decade, namely meso-scale surveys initiated and administered by indigenous organizations. These surveys offer the potential for filling information gaps, shedding light on culturally specific factors that shape demographic processes and health, and empowering indigenous organizations with data that could inform health initiatives. This article assesses the indigenous-run survey “2005 Health Analysis of the Shuar and Achuar Nations” of eastern Ecuador in which the authors were involved, which reached 1,943 households in 257 communities in Morona-Santiago Province. We present findings on fertility, migration, sanitation, and health, and assess the strengths and weaknesses of the survey. We argue that despite flaws in the survey design and implementation, this survey revealed important linkages among fertility, migration, and health. Such surveys have the potential to provide much needed detail, representativeness, and cultural specificity that macro and micro data sources cannot provide. We conclude with recommendations to improve surveys of this type. 相似文献
964.
Haishan Tian Lu Tang Yi Wang Xiaojie Wang Lili Guan Jian Zhang Xiaoping Wu Xiaokun Li 《International journal of peptide research and therapeutics》2011,17(2):123-129
Recombinant human keratinocyte growth factor-2 (rhKGF-2) has previously been expressed in Escherichia coli using isopropyl-β-d-thiogalactopyranoside (IPTG), a non-metabolizable and expensive compound, as the inducer. In order to determine whether IPTG
could be replaced with the cheap and natural lactose to induce rhKGF-2 expression, we examined the expression of rhKGF-2 in
flask culture and 30-l fermentation using lactose as the inducer. The optimized fermentation induced with lactose resulted
in 1,382 g of cell mass, corresponding to a 84% enhancement in cell mass compared with IPTG induction. While the expression
level of rhKGF-2 induced with lactose was comparable to that induced with IPTG, the solubility of target protein was increased
by lactose induction than by IPTG induction. The recombinant protein was further purified by cation exchange and heparin-affinity
chromatography. 255 milligrams of pure rhKGF-2 was achieved per liter culture by lactose induction, 52% higher than that obtained
by IPTG induction. A preliminary biochemical characterization of purified rhKGF-2 was performed by Western blotting and mitogenic
activity analysis, and the results demonstrated that the purified lactose-induced rhKGF-2 could react with anti-human KGF-2
antibody and stimulate the proliferation of FGFR2-IIIb-transfected mouse BaF3 cells as IPTG-induced rhKGF-2 could do. 相似文献
965.
Karen F Chambers Joanna F Pearson Davide Pellacani Naveed Aziz Miodrag Gužvić Christoph A Klein Shona H Lang 《Journal of biomedical science》2011,18(1):45
Background
Stromal signalling increases the lateral cell adhesions of prostate epithelial cells grown in 3D culture. The aim of this study was to use microarray analysis to identify significant epithelial signalling pathways and genes in this process. 相似文献966.
Yeo Dae Yoon Eun Sook Lee Jong Pil Park Mee Ree Kim Jun Won Lee Tae Hoon Kim Min Kyun Na Jin Hee Kim 《Biotechnology and Bioprocess Engineering》2011,16(6):1099-1105
Hizikia fusiforme is a commonly used food that possesses potent anti-bacterial, anti-fungal, and anti-inflammatory activities. The immunostimulatory
activities of aqueous extract of Hizikia fusiforme (HFAE) in RAW 264.7 macrophages and whole spleen cells were investigated. HFAE activated RAW 264.7 macrophages to produce
cytokines such as nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6) in
a dose-dependent manner. In addition, HFAE induced the mRNA expression of TNF-α, IL-1β, and IL-6 in RAW 264.7 macrophages.
Moreover, HFAE stimulated proliferation of whole spleen cells and reference mitogen. Taken together, the results demonstrate
that HFAE potently activates the immune function by regulating NO, TNF-α, IL-1β, and IL-6 in RAW 264.7 macrophage and promoting
spleen cell proliferation. 相似文献
967.
968.
Cytoglobin, generated using genetic engineering method, is a kind of recombinant human stellate cell activation-associated
protein. We speculate that it could influence the development of hepatic fibrosis like Sellate cell activation-associated
protein which was discovered by Kawada et al. Therefore, we investigated its anti-fibrosis effect on liver both in vivo and
in vitro. During our research, we found that cytoglobin showed obvious effect compared with the control group on Thioacetamide-induced
liver fibrosis in SD rats, including significantly decrease in aspartate aminotransferase, Hyaluronic acid, laminin and collagen
I(Col I) levels in serum and hydroxyproline in livers, which are the important indices reflecting the degree of hepatic fibrosis.
Meanwhile, the viability of rat hepatic stellate cell line T6 (HSC-T6) cells was inhibited by cytoglobin and the apoptosis
induced by cytoglobin in HSC-T6 cells was detected by Annexin V/PI double staining. Activation of the caspase cascade including
caspase-3 for the intrinsic pathways was demonstrated. The results also showed that the expression of Bcl-2 protein decreased
whereas that of Bax protein increased, leading to an increase of the Bax/Bcl-2 ratio. Our results demonstrated that cytoglobin
exhibited anti-fibrosis activity on livers in vivo and in vitro, involving apoptosis induction. 相似文献
969.
970.
Yao YW Shi Y Jia ZF Jiang YH Gu Z Wang J Aljofan M Sun ZG 《Histochemistry and cell biology》2011,136(2):205-215
To investigate the biological significance of ubiquitin carboxyl-terminal hydrolase L1 (UCH-L1) involvement in oocyte maturation,
we screened for proteins that bound to UCH-L1 in mouse ovaries, and we found that the prostate tumor overexpressed-1 (PTOV1)
protein was able to bind to UCH-L1. PTOV1 is highly expressed in prostate cancers and considered as a potential marker for
carcinogenesis and the progress of prostate cancer. It was reported that PTOV1 plays an important role in cell cycle regulation,
but its role in mammalian oocyte development and meiosis is still unclear. In this paper, it was found that the expression
levels of PTOV1 in mouse ovaries progressively increased from prepubescence to adulthood. And we found by immunohistochemistry
that PTOV1 spreaded in both the cytoplasm and nuclei of oocytes during prepuberty, but in normal adult mouse oocytes, it concentrated
not only in nuclei but also on the plasma membrane, though in some oocytes with abnormal shapes, PTOV1 did not display the
typical distribution patterns. In granulosa cells, however, it was found to locate in the cytoplasm at all the selected ages.
In postnatal mouse ovaries (28 days), estradiol treatment induced the adult-specific distribution pattern of PTOV1 in oocytes.
In addition, UCH-L1 was shown to be associated with CDK1, which participated in the regulation of cell cycle and oocyte maturation.
Therefore, we propose that the distribution changes of PTOV1 are age-dependent, and significant for mouse oocyte development
and maturation. Moreover, the discovery that PTOV1 is associated with UCH-L1 in mouse oocytes supports the explanations for
that UCH-L1 is involved in oocyte development and maturation, especially under the regulation of estrogen. 相似文献