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51.
Anthropogenic impacts have shifted aquatic ecosystems far from prehistoric baseline states; yet, understanding these impacts is impeded by a lack of available long-term data that realistically reflects the organisms and their habitats prior to human disturbance. Fish are excellent, and largely underused, proxies for elucidating the degree, direction and scale of shifts in aquatic ecosystems. This paper highlights potential sources of qualitative and quantitative data derived from contemporary, archived and ancient fish samples, and then, using key examples, discusses the types of long-term temporal information that can be obtained. This paper identifies future research needs with a focus on the Southern Hemisphere, as baseline shifts are poorly described relative to the Northern Hemisphere. Temporal data sourced from fish can improve our understanding of how aquatic ecosystems have changed, particularly when multiple sources of data are used, enhancing our ability to interpret the current state of aquatic ecosystems and establish effective measures to safeguard against further adverse shifts. The range of biological, ecological and environmental data obtained from fish can be integrated to better define ecosystem baseline states on which to establish policy goals for future conservation and exploitation practices.  相似文献   
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Plasmonics - In this work, we have performed a systematic investigation of the plasmon near-field effect on photoluminescence (PL) behavior of the annealed self-assembled gold nanostructured films....  相似文献   
54.
The study was aimed at evaluating antitumor and immunomodulatory effects of liposomal vaccine composed of P5 human epidermal growth factor receptor 2 (HER2)/neu-derived peptide coupled to the surface of high-temperature nanoliposomes containing distearoylphosphocholine:distearoylphosphoglycerol:Chol:dioleoylphosphatidylethanolamine (DOPE) comprising monophosphoryl lipid A (MPL) adjuvant in HER2/neu overexpressing the breast cancer model. BALB/c mice bearing TUBO carcinoma were subcutaneously immunized with formulations containing 10 µg P5 peptide and 25 µg MPL three times with 2-week intervals. To determine immuno responses in immunized mice, the amount of released interferon-γ and IL-4 were measured by the enzyme-linked immunospot method and the flow cytometric analysis on the isolated splenocytes. The results demonstrated that tumor-bearing mice immunized with Lip/DOPE/MPL/P5 formulation had the most released interferon-γ and the highest cytotoxic T lymphocyte responses that led to the lowest tumor size and the longest survival time than those of other formulations. The results achieved by Lip/DOPE/MPL/P5 formulation could make it a suitable candidate to induce effective antigen-specific tumor immunity against breast cancer.  相似文献   
55.
Trans-chalcone (1,3-diphenyl-2-propen-1-one), a biphenolic core structure of flavonoids precursor was tested for inhibitory activity toward alpha-amylase. Porcine pancreatic alpha-amylase was observed to be effectively inhibited by this compound, which showed competitive behavior with a K i of 48 μM. Soluble starch (the natural substrate of the enzyme) was used in this study in order to obtain more realistic results. The possible binding mode of the compound was assessed in silico, and the two residues Trp59, and Tyr62 were proposed as main interacting residues with trans-chalcone. In conclusion, this compound could be used to design effective inhibitors of alpha-amylase.  相似文献   
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Analysis of the intrinsic fluorescence profiles of individual marine algae can be used in general classification of organisms based on cell size and fluorescence properties. We describe the design and fabrication of a Microflow Cytometer on a chip for characterization of phytoplankton. The Microflow Cytometer measured distinct side scatter and fluorescence properties of Synechococcus sp., Nitzschia d., and Thalassiosira p.; measurements were confirmed using the benchtop Accuri C6 flow cytometer. The Microflow Cytometer proved sensitive enough to detect and characterize picoplankton with diameter approximately 1 μm and larger phytoplankton of up to 80 μm in length. The wide range in size discrimination coupled with detection of intrinsic fluorescent pigments suggests that this Microflow Cytometer will be able to distinguish different populations of phytoplankton on unmanned underwater vehicles.  相似文献   
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Fruits of citrus cultivars contain bioflavonoids and some other important secondary metabolites in pharmaceutical and nutritional industries. The present experiment was designed to investigate the correlation between the content of flavonoid components like naringin, hesperidin, and neohesperidin of the scions fruits and the same parameters in rootstocks fruits. Six-year-old trees including four citrus cultivars of ‘Moro’, ‘Mars’, ‘Salustiana’, and ‘Italian’ which were previously grafted on the four different rootstocks including ‘Yuzu’, ‘Shelmahalleh’, ‘Citromelo’, and ‘Sour orange’ were selected as experimental trees. The content of the mentioned flavonoids was investigated in the peel and pulp of the fruits of both scions and rootstocks. The results showed that the measured parameters were significantly influenced by scions, rootstocks, and tissues. Based on the obtained results, it can be suggested that the accumulation of chemicals in citrus fruit depends on genetic and inherent abilities of the scion, more than what was previously believed, while the rootstock can also play an important role in the accumulation of these substances.  相似文献   
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We compared the therapeutic effects of autologous and nonautologous adipose-derived mesenchymal stem cell (ADMSC), in ameliorating the renal function in a rabbit model of acute pyelonephritis. The difference of perirenal and neck subcutaneous ADMSCs were also evaluated. Twenty female rabbits were apportioned to 5 groups. In group I (n = 4), the rabbits were injected direct inoculation of Escherichia coli (E. coli) into the right kidney. In group II (n = 4), autologous ADMSCs obtained from nape adipose tissue were injected into the subcapsular space 1 week after E. coli injection, while nonautologous ADMSCs of the same origin (from male rabbits) were applied in group III (n = 4). In group IV (n = 4), autologous perirenal ADMSCs were applied with the same method, while perirenal nonautologous ADMSCs from male rabbits were used in group V (n = 4). Technetium-99m-DMSA renal scan was performed 1, 2 and 4 months post-injection in all groups. Kidneys were excised for the evaluation of histopathological changes in the same time points. PCR examination for detection of Y-chromosome (in group III and V) and fluorescent evaluation (in group II and IV) were also performed to determine the fate of injected cells. Injection of autologous ADMSCs resulted in more satisfactory outcomes in reduction of interstitial fibrosis, tubular, and glomerular atrophy as compared to nonautologous groups. However, histopathological ameliorations were significantly better in group IV in which autologous perirenal ADMSC was applied. Remarkably, two months after the injection, Technetium-99m-DMSA renal scan showed that right kidney reached to near normal cortical function (48 and 45%) in group IV and V, respectively as compared to groups II (41%) and III (37%). Autologous ADMSCs may have better results in cell therapy as compared to nonautologous cells. However, more satisfactory outcomes may be obtained when the cell source is selected from the surrounding adipose tissue.  相似文献   
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It has been more than a decade since Acetobacter senegalensis was isolated, identified and described as a thermotolerant strain of acetic acid bacteria. It was isolated from mango fruits in Senegal and used for industrial vinegar production in developing countries, mainly in sub-Saharan Africa. The strain was tested during several spirit vinegar fermentation processes at relatively high temperatures in accordance with African acclimation. The upstream fermentation process had significant stress factors, which are highlighted in this review so that the fermentation process can be better controlled. Due to its high industrial potential, this strain was extensively investigated by diverse industrial microbiologists worldwide; they concentrated on its microbiological, physiological and genomic features. A research group based in Belgium proposed an important project for the investigation of the whole-genome sequence of A. senegalensis. It would use a 454-pyrosequencing technique to determine and corroborate features that could give this strain significant diverse bio-industrial applications. For instance, its application in cocoa bean fermentation has made it a more suitable acetic acid bacterium for the making of chocolate than Acetobacter pasteurianus. Therefore, in this paper, we present a review that summarizes the current research on A. senegalensis at its microbial and genomic levels and also its specific bio-industrial applications, which can provide economic opportunities for African agribusiness. This review summarizes the physiological and genomic characteristics of Acetobacter senegalensis, a thermotolerant strain isolated from mango fruits and intended to be used in industrial vinegar fermentation processes. It also explores other bio-industrial applications such as cocoa fermentation. Vinegar fermentation is usually performed with mesophilic strains in temperate regions of the world. Developing countries, such as Senegal, import vinegar or make ‘fake’ vinegar by diluting acetic acid obtained from petrochemicals. The use of a thermotolerant Acetobacter senegalensis strain as a solid functional starter culture, as well as the design of a new adapted bioreactor, has significantly contributed to food security and the creation of small- to medium-sized enterprises that produce mango vinegar in West Africa.  相似文献   
60.
Leuprolide acetate (LA) has been accepted as treatment for prostatic cancer and is currently also being evaluated in phase II clinical trials for the treatment of Alzheimer's disease. In this study, the zinc complex of leuprolide was prepared and its structure determined by Fourier-transform infrared (FTIR), differential scanning calorimetry (DSC), UV, X-ray diffraction (XRD), atomic absorption spectroscopy, elemental analysis, and compared with these parameters for leuorolide acetate. Also, the in vitro release profile of leuprolide and its complex form in situ forming implant (ISFI) in comparison to a commercial formulation (Eligard) was investigated. These studies indicate that the zinc complex can be effectively synthesized and influenced on tri-phasic pattern after burst release of LA from the ISFI and shifts this trend to a continuous release profile. Non-linear regression test confirmed this transformation as a zero-order release profile as well.  相似文献   
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