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81.
82.
Oluwatosin Gbemisola Oladipo Olusegun Olufemi Awotoye Akin Olayinka Obinna Tobechukwu Ezeokoli Mark Steve Maboeta Cornelius Carlos Bezuidenhout 《Bioremediation Journal》2016,20(4):287-297
Increased heavy metal pollution generated through anthropogenic activities into the environment has necessitated the need for eco-friendly remediation strategies such as mycoremediation. With a view to prospecting for fungi with heavy metal remediation potentials, the tolerance of five Aspergillus species isolated from soils of three active gold and gemstone mining sites in southwestern Nigeria to varied heavy metal concentrations was investigated. Isolated Aspergillus strains were identified based on the internal transcribed spacer 1 and 2 (ITS 1 and ITS 2) regions. Growth of Aspergillus strains were challenged with a range of varied concentrations of heavy metals: cadmium (Cd) (0–100), copper (Cu) (0–1000), lead (Pb) (0–400), arsenic (As) (0–500), and iron (Fe) (0–800) concentrations (ppm) incorporated into Malt Extract Agar (MEA) in triplicates. Mycelial radial growths were recorded at intervals of 3 days during a 13-day incubation period. Aspergillus strains were identified as A. tubingensis, A. fumigatus, A. terreus, A. nidulans, and A. nomius. A. tubingensis tolerated Cd, Cu, Pb, As, and Fe at all test concentrations (100–1000 ppm), showing no significant (p > .05) difference compared with the control. Similarly, A. nomius tolerated all concentrations of Cu, Pb, As, and Fe and only 50 ppm Cd concentrations. A. nidulans, A. terreus, and A. fumigatus, on the other hand, tolerated all concentrations of Cu, Pb, and Fe with no statistical significance (p > .05) difference from the controls. Overall, the Aspergillus species showed tolerance to heavy metal concentrations above permissible limits for contaminated soils globally. These heavy metal tolerance traits exhibited by the Aspergillus isolates may suggest that they are potential candidates for bioremediation of heavy metal–polluted environments. 相似文献
83.
S. Akin T. Yetgin J. J. Brugts A. Dirkali F. Zijlstra T. J. Cleophas 《Netherlands heart journal》2013,21(3):146-151
Background
It is generally believed that there is a beneficial effect of collaterals on death and re-infarction statistics in patients with coronary artery disease (CAD) but studies to date are small and inconsistent.Objective
To meta-analyse the studies published in this field in order to obtain more powerful information.Methods
We searched Medline and major journals (2000 to 2011) for studies evaluating the effect of coronary collaterals on mortality. Publication bias, lack of heterogeneity, and lack of robustness were assessed using the standard procedures for such purposes.Results
A total of 10 studies describing mortality, enrolling 6791 participants, were included in this analysis. In patients with collateralisation a significant relation with reduced mortality was seen compared with those without collateralisation, at an odds ratio of 0.47, p?<?0.0001, and a reduction in deaths and re-infarctions at 0.54, p?<?0.0001. Some publication bias, some heterogeneity and some lack of robustness were demonstrated. A meta-regression with the odds ratios of the presence of traditional atherosclerotic risk factors as predictors and the odds ratios of mortality and the composite deaths and re-infarctions as outcome showed no relationships.Conclusions
In CAD patients from the post-percutaneous coronary intervention era the presence of collaterals reduced mortality by 0.47 (p?<?0.0001) and deaths and re-infarctions by 0.54 (p?<?0.0001). Furthermore, in the present meta-data, the atherosclerotic risk factors were no more present in patients with collaterals than they were in those without. 相似文献84.
Brandy L. Akin Thomas D. Hurley Zhenhui Chen Larry R. Jones 《The Journal of biological chemistry》2013,288(42):30181-30191
P-type ATPases are a large family of enzymes that actively transport ions across biological membranes by interconverting between high (E1) and low (E2) ion-affinity states; these transmembrane transporters carry out critical processes in nearly all forms of life. In striated muscle, the archetype P-type ATPase, SERCA (sarco(endo)plasmic reticulum Ca2+-ATPase), pumps contractile-dependent Ca2+ ions into the lumen of sarcoplasmic reticulum, which initiates myocyte relaxation and refills the sarcoplasmic reticulum in preparation for the next contraction. In cardiac muscle, SERCA is regulated by phospholamban (PLB), a small inhibitory phosphoprotein that decreases the Ca2+ affinity of SERCA and attenuates contractile strength. cAMP-dependent phosphorylation of PLB reverses Ca2+-ATPase inhibition with powerful contractile effects. Here we present the long sought crystal structure of the PLB-SERCA complex at 2.8-Å resolution. The structure was solved in the absence of Ca2+ in a novel detergent system employing alkyl mannosides. The structure shows PLB bound to a previously undescribed conformation of SERCA in which the Ca2+ binding sites are collapsed and devoid of divalent cations (E2-PLB). This new structure represents one of the key unsolved conformational states of SERCA and provides a structural explanation for how dephosphorylated PLB decreases Ca2+ affinity and depresses cardiac contractility. 相似文献
85.
W. THEUNIS S. BLÄHSER R. HUYBRECHTS A. DE LOOF 《Invertebrate reproduction & development.》2013,57(1-3):111-117
Summary Materials immunologically related to luteinising hormone (LH), follicle stimulating hormone (FSH) and the gonadotropin releasing hormone (GnRH) were localised in cerebral tissue of Locusta migratoria and Sarcophaga bullata by means of the peroxidase-antiperoxidase method. Several polyclonal and a monoclonal antisera were used. From the third larval instar a positive reaction was observed in cells located in several parts of the brain. Each antiserum reacted with a constant number of well defined cells and nerve fibers. No differences between sexes were observed. 相似文献
86.
87.
In this experiment, the effects of different doses of vasoactive intestinal peptide (VIP) and naloxone (NLX) combinations on survival rates were investigated in rats exposed to 40% hemorrhage. A combination of 25 ng.kg-1 VIP+5 mg.kg-1 NLX showed the best results on survival. The important prospect of this combination is to have the most potent inhibitory effect on mast cell degranulation. When this combination was given together with shed blood reperfusion and 7.5% NaCl, survival rate increased relative to the administration of shed blood alone and of 7.5% NaCl. These findings suggest that inhibition of mast cell degranulation has a beneficial effect on severe hemorrhage. 相似文献
88.
M Yuksel DG Colak M Akin I Cianga M Kukut EI Medine M Can S Sakarya P Unak S Timur Y Yagci 《Biomacromolecules》2012,13(9):2680-2691
The generation and fabrication of nanoscopic structures are of critical technological importance for future implementations in areas such as nanodevices and nanotechnology, biosensing, bioimaging, cancer targeting, and drug delivery. Applications of carbon nanotubes (CNTs) in biological fields have been impeded by the incapability of their visualization using conventional methods. Therefore, fluorescence labeling of CNTs with various probes under physiological conditions has become a significant issue for their utilization in biological processes. Herein, we demonstrate a facile and additional fluorophore-free approach for cancer cell-imaging and diagnosis by combining multiwalled CNTs with a well-known conjugated polymer, namely, poly(p-phenylene) (PP). In this approach, PP decorated with poly(ethylene glycol) (PEG) was noncovalently (π-π stacking) linked to acid-treated CNTs. The obtained water self-dispersible, stable, and biocompatible f-CNT/PP-g-PEG conjugates were then bioconjugated to estrogen-specific antibody (anti-ER) via -COOH functionalities present on the side-walls of CNTs. The resulting conjugates were used as an efficient fluorescent probe for targeted imaging of estrogen receptor overexpressed cancer cells, such as MCF-7. In vitro studies and fluorescence microscopy data show that these conjugates can specifically bind to MCF-7 cells with high efficiency. The represented results imply that CNT-based materials could easily be fabricated by the described approach and used as an efficient "fluorescent probe" for targeting and imaging, thereby providing many new possibilities for various applications in biomedical sensing and diagnosis. 相似文献
89.
Paulo H. Rodrigues Leticia Reyes Amandeep S. Chadda Myriam Bélanger Shannon M. Wallet Debra Akin William Dunn Jr Ann Progulske-Fox 《PloS one》2012,7(12)
Both epidemiologic and experimental findings suggest that infection with Porphyromonas gingivalis exacerbates progression of atherosclerosis. As P. gingivalis exhibits significant strain variation, it is reasonable that different strains possess different capabilities and/or mechanisms by which they promote atherosclerosis. Using P. gingivalis strains that have been previously evaluated in the ApoE null atherosclerosis model, we assessed the ability of W83, A7436, 381, and 33277 to adhere, invade, and persist in human coronary artery endothelial (HCAE) cells. W83 and 381 displayed an equivalent ability to adhere to HCAE cells, which was significantly greater than both A7436 and 33277 (P<0.01). W83, 381, and 33277 were more invasive than A7436 (P<0.0001). However, only W83 and A7436 were able to remain viable up to 48 hours in HCAE cell cultures, whereas 381 was cleared by 48 hours and 33277 was cleared by 24 hours. These differences in persistence were in part due to strain specific differences in intracellular trafficking. Both W83 and 381 trafficked through the autophagic pathway, but not A7436 or 33277. Internalized 381 was the only strain that was dependent upon the autophagic pathway for its survival. Finally, we assessed the efficacy of these strains to activate HCAE cells as defined by production of IL-6, IL-8, IL-12p40, MCP-1, RANTES, TNF-α, and soluble adhesion molecules (sICAM-1, sVCAM-1, and sE-selectin). Only moderate inflammation was observed in cells infected with either W83 or A7436, whereas cells infected with 381 exhibited the most profound inflammation, followed by cells infected with 33277. These results demonstrate that virulence mechanisms among different P. gingivalis strains are varied and that pathogenic mechanisms identified for one strain are not necessarily applicable to other strains. 相似文献
90.
Jared A. Niska Jeffrey A. Meganck Jonathan R. Pribaz Jonathan H. Shahbazian Ed Lim Ning Zhang Brad W. Rice Ali Akin Romela Irene Ramos Nicholas M. Bernthal Kevin P. Francis Lloyd S. Miller 《PloS one》2012,7(10)