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51.
Cooper CR Graves B Pruitt F Chaib H Lynch JE Cox AK Sequeria L van Golen KL Evans A Czymmek K Bullard RS Donald CD Sol-Church K Gendernalik JD Weksler B Farach-Carson MC Macoska JA Sikes RA Pienta KJ 《Journal of cellular biochemistry》2008,104(6):2298-2309
An unbiased cDNA expression phage library derived from bone-marrow endothelial cells was used to identify novel surface adhesion molecules that might participate in metastasis. Herein we report that reticulocalbin 1 (RCN1) is a cell surface-associated protein on both endothelial (EC) and prostate cancer (PCa) cell lines. RCN1 is an H/KDEL protein with six EF-hand, calcium-binding motifs, found in the endoplasmic reticulum. Our data indicate that RCN1 also is expressed on the cell surface of several endothelial cell lines, including human dermal microvascular endothelial cells (HDMVECs), bone marrow endothelial cells (BMEC), and transformed human bone marrow endothelial cells (TrHBMEC). While RCN1 protein levels were highest in lysates from HDMVEC, this difference was not statistically significant compared BMEC and TrHBMEC. Given preferential adhesion of PCa to bone-marrow EC, these data suggest that RCN1 is unlikely to account for the preferential metastasis of PCa to bone. In addition, there was not a statistically significant difference in total RCN1 protein expression among the PCa cell lines. RCN1 also was expressed on the surface of several PCa cell lines, including those of the LNCaP human PCa progression model and the highly metastatic PC-3 cell line. Interestingly, RCN1 expression on the cell surface was upregulated by tumor necrosis factor alpha treatment of bone-marrow endothelial cells. Taken together, we show cell surface localization of RCN1 that has not been described previously for either PCa or BMEC and that the surface expression on BMEC is regulated by pro-inflammatory TNF-alpha. 相似文献
52.
Dr. A. Kalyebi S. Sithanantham W. A. Overholt S. A. Hassan J. M. Mueke 《Biocontrol Science and Technology》2005,15(3):255-270
Six native Kenyan species/strains of Trichogramma and Trichogrammatoidea, recovered from Helicoverpa armigera were evaluated at six different temperatures (10, 15, 20, 25, 30 and 35°C) and two relative humidity levels (40–50 and 70–80%) with the aim of selecting strains adapted to warmer temperature regimes. The species/strains were collected from low (<700 m), medium (between 700 and 1200 m) and high altitude (>1200 m) locations and were evaluated for parasitism, adult longevity, progeny production and progeny sex ratio at the different environmental regimes. Eggs of the factitious host, Corcyra cephalonica Stainton (Lepidoptera: Pyralidae) were used in the investigations. Temperature and humidity interactions affected parasitism and progeny production. The highest parasitism at the two humidity levels was at 25 and 30°C for all the strains evaluated. Adult longevity was also significantly affected by the interaction of temperature and relative humidity and was longer at the lower than higher relative humidity. Survival followed a type I survivorship curve at lower temperatures and a type III survivorship curve at the higher temperatures. Trichogramma sp. nr. mwanzai from low altitude, Trichogramma sp. nr. mwanzai from medium altitude and Trichogrammatoidea sp. nr. lutea also from medium altitude lived longer than other strains at all the temperatures and relative humidity levels evaluated, including the warmest regimes of 30 and 35°C. These strains appear promising as candidates for augmentative biocontrol of H. armigera in Kenya. 相似文献
53.
People dwelling in different cities of the Potohar region, Pakistan, are mostly dependent on surface water for drinking and domestic use. In an attempt to make available potable, safe water, filtration plants were constructed along with dams in the Potohar region. Water samples from these filtration plants were collected and analyzed for total and faecal coliform bacteria as well as for total viable count. Results showed that bacterial indicators of faecal contamination were numerous and significantly greater than World Health Organization recommended guidelines. Accordingly, antibacterial activity of methanolic and aqueous extracts of different parts of Solanum surrattense were assessed in vitro against waterborne pathogens. Fruits exhibited more antibacterial activities at incubation at 37°C than shoots and roots, which showed lowest Minimum Inhibitory Concentration (MIC) and zones of inhibition. These results suggest that plants offer a great potential for purification of drinking water that needs to be explored further because fruit extract of the aforementioned plant can be of practical use against waterborne pathogens. 相似文献
54.
Parastoo Pourali Behrooz Yahyaei Hatef Ajoudanifar Rahele Taheri Hassan Alavi Ashraf Hoseini 《Current microbiology》2014,69(6):785-793
Different wound dressings with antibacterial property have been surveyed and one among them is bacterial cellulose (BC). Since the BC does not have antibacterial property, the biologically produced silver nanoparticles (SNPs) were impregnated into the BC. For the BC production, Hestrin–Schramm broth was used. Formation of the BC was proven by enzymatic hydrolysis. For SNPs production, the bacterial supernatant was treated with AgNO3 and formation of SNPs was monitored through spectrophotometer, TEM and XRD. For impregnation of SNPs into the BC, the cleaned membrane was placed in the bacterial supernatant that contained 1 mmol of AgNO3. The antibacterial assay was done for the BC/SNPs. Enzymatic hydrolysis proved the presence of the BC. Spectrophotometer and XRD results showed the formation of SNPs. TEM analysis revealed the presence of SNPs with sizes around 5–100 nm. SEM micrographs showed the impregnation of SNPs into the BC. Antibacterial test exhibited the antibacterial activity of the BC/SNPs. 相似文献
55.
Nadia Amrani Xin D. Gao Pengpeng Liu Alireza Edraki Aamir Mir Raed Ibraheim Ankit Gupta Kanae E. Sasaki Tong Wu Paul D. Donohoue Alexander H. Settle Alexandra M. Lied Kyle McGovern Chris K. Fuller Peter Cameron Thomas G. Fazzio Lihua Julie Zhu Scot A. Wolfe Erik J. Sontheimer 《Genome biology》2018,19(1):214
Background
The development of CRISPR genome editing has transformed biomedical research. Most applications reported thus far rely upon the Cas9 protein from Streptococcus pyogenes SF370 (SpyCas9). With many RNA guides, wildtype SpyCas9 can induce significant levels of unintended mutations at near-cognate sites, necessitating substantial efforts toward the development of strategies to minimize off-target activity. Although the genome-editing potential of thousands of other Cas9 orthologs remains largely untapped, it is not known how many will require similarly extensive engineering to achieve single-site accuracy within large genomes. In addition to its off-targeting propensity, SpyCas9 is encoded by a relatively large open reading frame, limiting its utility in applications that require size-restricted delivery strategies such as adeno-associated virus vectors. In contrast, some genome-editing-validated Cas9 orthologs are considerably smaller and therefore better suited for viral delivery.Results
Here we show that wildtype NmeCas9, when programmed with guide sequences of the natural length of 24 nucleotides, exhibits a nearly complete absence of unintended editing in human cells, even when targeting sites that are prone to off-target activity with wildtype SpyCas9. We also validate at least six variant protospacer adjacent motifs (PAMs), in addition to the preferred consensus PAM (5′-N4GATT-3′), for NmeCas9 genome editing in human cells.Conclusions
Our results show that NmeCas9 is a naturally high-fidelity genome-editing enzyme and suggest that additional Cas9 orthologs may prove to exhibit similarly high accuracy, even without extensive engineering.56.
Self‐Powered Wireless Sensor Node Enabled by a Duck‐Shaped Triboelectric Nanogenerator for Harvesting Water Wave Energy 下载免费PDF全文
Abdelsalam Ahmed Zia Saadatnia Islam Hassan Yunlong Zi Yi Xi Xu He Jean Zu Zhong Lin Wang 《Liver Transplantation》2017,7(7)
This paper presents a fully enclosed duck‐shaped triboelectric nanogenerator (TENG) for effectively scavenging energy from random and low‐frequency water waves. The design of the TENG incorporates the freestanding rolling mode and the pitch motion of a duck‐shaped structure generated by incident waves. By investigating the material and structural features, a unit of the TENG device is successfully designed. Furthermore, a hybrid system is constructed using three units of the TENG device. The hybrid system achieves an instantaneous peak current of 65.5 µA with an instantaneous output power density of up to 1.366 W m?2. Following the design, a fluid–solid interaction analysis is carried out on one duck‐shaped TENG to understand the dynamic behavior, mechanical efficiency, and stability of the device under various water wave conditions. In addition, the hybrid system is experimentally tested to enable a commercial wireless temperature sensor node. In summary, the unique duck‐shaped TENG shows a simple, cost‐effective, environmentally friendly, light‐weight, and highly stable system. The newly designed TENG is promising for building a network of generators to harvest existing blue energy in oceans, lakes, and rivers. 相似文献
57.
Enhanced evapotranspiration was observed during extreme drought from Miscanthus,opposite of other crops 下载免费PDF全文
Eva Joo Marcelo Zeri Mir Zaman Hussain Evan H. DeLucia Carl J. Bernacchi 《Global Change Biology Bioenergy》2017,9(8):1306-1319
The impact of extreme drought and heat stress that occurred in the Midwestern U.S. in 2012 on evapotranspiration (ET), net ecosystem productivity (NEP), and water‐use efficiency (WUE) of three perennial ecosystems (switchgrass, miscanthus, prairie) and a maize/soybean agroecosystem was studied as part of a long‐term experiment. Miscanthus had a slower initial response but an eventually drastic ET as drought intensified, which resulted in the largest water deficit among the crops. The substantially higher ET at peak drought was likely supplied by access to deep soil water, but suggests that stomatal conductance of miscanthus during the drought may respond differently than the other ecosystems, consistent with an anisohydric strategy. While there was a discrepancy in the water consumption of maize and switchgrass/prairie in the early time of drought, all these ecosystems followed a water‐saving strategy when drought intensified. The gross primary production (GPP) of miscanthus dropped, but was reversible, when temperature reached 40 °C and still provided the largest total GPP among the ecosystems. Increased ET for miscanthus during 2012 resulted a large decline in ecosystem WUE compared to what was observed in other years. The biophysical responses of miscanthus measured during an extreme, historic drought suggest that this species can maintain high productivity longer than other ecosystems during a drought at the expense of water use. While miscanthus maintained productivity during drought, recovery lagged associated with depleted soil moisture. The enhanced ET of miscanthus may intensify droughts through increase supply of deep soil moisture to the atmosphere. 相似文献
58.
The present study aimed to investigate the effects of different levels of dietary supplementation of grape seed extract (GSE) on growth performance, carcass traits and antioxidant status of rabbits under heat stress conditions (temperature humidity index 87.5–93.5). Weaned male New Zealand White (NZW) rabbits about 6 weeks old (n = 144, mean body weight 705 g) were randomly allotted to four dietary groups. The Control group was fed a basal diet without GSE; the experimental groups received the basal diet with 100, 200 and 300 mg GSE/kg (Groups 100 GSE, 200 GSE and 300 GSE, respectively). The experimental period lasted for 8 weeks. Compared with other groups, rabbits of Group 300 GSE had the best body weight gain and feed conversion ratio and the lowest mortality. Dietary GSE improved carcass weight, percentage of hot carcass, intestine and edible giblets, while total non-edible parts were reduced (p ≤ 0.05) in comparison with the Control group. In Groups 200 GSE and 300 GSE, plasma total protein, albumin and globulin were increased (p ≤ 0.05). In contrast, all supplementation levels of GSE reduced (p ≤ 0.05) the plasma concentrations of total lipids, total cholesterol, triglycerides and low-density lipoproteins. Antioxidant enzymes of rabbits (superoxide dismutase, catalase, glutathione peroxidase, glutathione transferase) and total antioxidant capacity in blood were increased (p ≤ 0.05) by adding dietary GSE. However, malondialdehyde was reduced (p ≤ 0.001) with increasing GSE levels. Generally, grape seeds can be considered as rich source of phenolic and flavonoid compounds. The results of the study revealed that all tested levels of GSE were useful as a natural protection against heat stress to maintain performance, carcass traits and antioxidant status and could reduce the negative effects of heat stress in rabbits. 相似文献
59.
Sajad Ali Zahoor Ahmad Mir Anshika Tyagi Javaid A. Bhat Narayanappa Chandrashekar Pradeep Kumar Papolu Sandhya Rawat Anita Grover 《Acta Physiologiae Plantarum》2017,39(12):268
Pathogenesis-related proteins (PRs) are the antimicrobial proteins which are commonly used as signatures of defense signaling pathways and systemic acquired resistance. However, in Brassica juncea most of the PR proteins have not been fully characterized and remains largely enigmatic. In this study, full-length cDNA sequences of SA (PR1, PR2, PR5) and JA (PR3, PR12 and PR13) marker genes were isolated from B. juncea and were named as BjPR proteins. BjPR proteins showed maximum identity with known PR proteins of Brassica species. Further, expression profiling of BjPR genes were investigated after hormonal, biotic and abiotic stresses. Pre-treatment with SA and JA stimulators downregulates each other signature genes suggesting an antagonistic relationship between SA and JA in B. juncea. After abscisic acid (ABA) treatment, SA signatures were downregulated while as JA signature genes were upregulated. During Erysiphe cruciferarum infection, SA- and JA-dependent BjPR genes showed distinct expression pattern both locally and systemically, thus suggesting the activation of SA- and JA-dependent signaling pathways. Further, expression of SA marker genes decreases while as JA-responsive genes increases during drought stress. Interestingly, both SA and JA signature genes were induced after salt stress. We also found that BjPR genes displayed ABA-independent gene expression pattern during abiotic stresses thus providing the evidence of SA/JA cross talk. Further, in silico analysis of the upstream regions (1.5 kb) of both SA and JA marker genes showed important cis-regulatory elements related to biotic, abiotic and hormonal stresses. 相似文献
60.