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151.
Magnetic agarose microspheres (MAMS), magnetic cellulose microspheres (MCMS), and magnetic poly(vinyl alcohol) microspheres (MPVAMS) were prepared by various different preparation methods. MCMS coupled with anti-IFN alpha-2b monoclonal antibodies (mAb) were selected for the purification of interferon alpha-2b (IFN alpha-2b) after performance characterization among microspheres. Parameters of immunomagnetic separation (IMS), including binding mAb, elution behavior, and sample pretreatment conditions, were optimized to improve the purification efficiency of the separation of IFN alpha-2b by MCMS. Size-exclusion HPLC (HPSEC) showed that the IFN alpha-2b was purified from crude cell lysate had an overall purity of 92.9%, while immunological and biological assays showed an activity recovery of 88.5% and specific antiviral activity of 2.7 x 10(8) IU/mg. Identity and molecular mass of purified IFN alpha-2b were confirmed by western blot and matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS) analysis. This study illustrated the favorable separation media which combined desired properties for the development of magnetic separation of biological materials.  相似文献   
152.
Targeted drug delivery systems for cancer improves anti-tumor efficacy and reduces systemic toxicity by restricting availability of cytotoxic drugs within tumors. Targeting moieties, such as natural ligands (folic acid, transferrin, and biotin) which are overexpressed on tumors, have been used to enhance liposome-encapsulated drug accumulation within tumors and resulted in better control. In this report, we explored the scope of targeting ligand folic acid, which is incorporated in liposome systems using folic acid-modified cholesterol (CPF), enabled highly selective tumor-targeted delivery of liposome-encapsulated doxorubicin and resulted in increased cytotoxicity within tumors. Folate-tagged poloxamer-coated liposomes (FDL) were found to have significantly higher cellular uptake than conventional poloxamer-coated liposomes (DL), as confirmed by fluorometric analysis in B16F10 melanoma cells. Biodistribution study of the radiolabeled liposomal system indicated the significantly higher tumor uptake of FDL as compared to DL. Anti-tumor activity of FDL against murine B16F10 melanoma tumor-bearing mice revealed that FDL inhibited tumor growth more efficiently than the DL. Taken together, the results demonstrated the significant potential of the folate-conjugated nanoliposomal system for drug delivery to tumors.  相似文献   
153.
The effects of the abundance of acorns of the oak, Quercus crispula, on the population dynamics of three rodent species (Apodemus speciosus, A. argenteus, and Clethrionomys rufocanus) were analyzed using time series data (1992–2006). The data were obtained in a forest in northern Hokkaido, Japan, by live trapping rodents and directly counting acorns on the ground. Apodemus speciosus generally increased in abundance following acorn masting. However, the clear effect of acorn abundance was not detected for the other two rodent species. Acorns of Q. crispula contain tannins, which potentially have detrimental effects on herbivores. Apodemus speciosus may reduce the damage caused by acorn tannins with tannin-binding salivary proteins and tannase-producing bacteria, whereas such physiological tolerance to tannins is not known in the other two rodent species. The differences in the effects of acorns between the three species may be due to differences in their physiological tolerance to tannins.  相似文献   
154.
Patent analysis with the help of the strategic mining of patents from databases is important and useful within the framework of application-oriented research and its commercialization. In the analysis reported here, we have mined cyanobacterial patents from the patent database of the United States Patent and Trademark Office (USPTO). In order to make an assessment of the commercial potentials of cyanobacteria, we conducted the patent search (from 1976 to April 2006) using certain generic terms and the 84 genera of cyanobacteria as keywords. The search was performed in two major ways – searching the abstracts and claims of the patents cumulatively and searching the entire patent documents by the mode of ‘all fields’ in USPTO. In the abstract- and claims-based search, 234 patents were obtained after the removal of overlapping patents among the keywords. An additional 31 patents were added following the ‘all fields’ search; these patents were not covered in the search that was based on abstracts and claims. The entire package of 265 patents, of which 244 were related to cyanobacteria, was then analyzed. Information derived from these patents identified five major areas of cyanobacterial utilization. Cyanobacteria have been patented as a source of a wide spectrum of products, for medical, agriculture and environmental applications, for gene-based products, for methods of cultivation and for methods of control. The chronological development in granting cyanobacterial patents was also traced. This study demonstrates that such strategic mining and analysis of patent data can be used as an index for future development.  相似文献   
155.
To synthesize and secrete heterologous proteins in an attenuated Vibrio anguillarum strain for potential multivalent live vaccine development, different antigen-delivery systems based on bacterial-originated secretion signal peptides (SPs) were designed and identified in this work. Four SPs were derived from hemolysin of Escherichia coli, RTX protein of V. cholerae, hemolysin of V. anguillarum, zinc-metalloprotease of V. anguillarum, respectively, and their abilities to support secretion of green fluorescent protein (GFP) in an attenuated V. anguillarum strain MVAV6203 were assayed. Immunodetection of GFP showed that the capability of the tested signal leaders to direct secretion of GFP varied greatly. Although all the four signal peptide-fused GFPs could be expressed correctly and trapped intracellularly in recombinant strains, only the EmpA signal peptide could confer efficient secretion to GFP. For the investigation of its potential application in live bacteria carrier vaccines, a heterologous protein EseB of Edwardsiella tarda was fused to the SP(empA) antigen-delivery system and introduced into the strain MVAV6203. Further analysis of EseB demonstrated that the constructed SP(empA) antigen-delivery system could be used to secrete foreign protein in attenuated V. anguillarum and be available for carrier vaccines development.  相似文献   
156.
MYH9-related diseases (MYH9-RD) are a group of autosomal dominant diseases caused by mutations in the MYH9 gene, which are featured by thrombocytopenia, giant platelets and granulocyte cytoplasmic inclusion bodies. MYH9-RD patients generally suffer from bleeding syndromes, progressive kidney disease, deafness, or cataracts. Here, we reported on a case of MYH9-RD. A novel heterozygous mutation of MYH9 (c.2344-2345delGTinsTA, p.T782Y) was discovered by targeted sequencing technology. Immunofluorescence analysis of neutrophils confirmed abnormal aggregation of MYH9 protein. The results of this study should expand the MYH9 gene mutation spectrum and provide reference for subsequent researchers and genetic counseling.  相似文献   
157.
Beckerman AP  Wieski K  Baird DJ 《Oecologia》2007,152(2):335-343
Predator-generated variation in prey energy intake remains the dominant explanation of adaptive response to predation risk in prey life history, morphology and physiology across a wide range of taxa. This "behavioural hypothesis" suggest that chemical or visual signals of predation risk reduce prey energy intake leading to a life history characterized by a small size and late age at maturity. However, size-selective predation can induce either smaller size-early age or large size-late age life history. The alternative "physiological hypothesis" suggests that size-selective cues decouple the relationship between energy and life history, acting instead directly on development. Here we use a series of experiments in a fish-daphnid predator-prey system to ask whether size-selective predator cues induce a physiological mediation of development, overshadowing behaviourally based changes in food intake. We found fish chemical cues reduce the net energy intake in Daphnia magna, suggesting a behaviourally mediated reduction in energy. Experimental manipulation of food levels show further that reductions in food lead to later but smaller size at maturity. However, in line with the physiological hypothesis, we show that D. magna matures earlier and at a smaller size when exposed to fish predation cues. Furthermore, our data shows that they do this by increasing their development rate (earlier maturity) for a given growth rate, resulting in a smaller size at maturity. Our data, from a classic size-selective predation system, indicate that predator-induced changes in this system are driven by physiological mediation of development rather than behavioural mediation of energy intake.  相似文献   
158.
Methylphenidate is commonly used for the treatment of attention deficit/hyperactivity disorder. There are still few works regarding the effects of methylphenidate on brain energy metabolism. Thus, in the present study we evaluated the effect of chronic administration of methylphenidate on the activities of mitochondrial respiratory chain complexes I and III in the brain of young rats. The effect of acute administration of methylphenidate on mitochondrial respiratory chain complexes I, II, III and IV in the brain of young rats was also investigated. For acute administration, a single injection of methylphenidate was given to rats on postnatal day 25. For chronic administration, methylphenidate injections were given starting at postnatal day 25 once daily for 28 days. Our results showed that complexes I and III were not affected by chronic administration of methylphenidate. Moreover, the acute administration of methylphenidate decreased complex I activity in cerebellum and prefrontal cortex, whereas complexes II, III and IV were not altered.  相似文献   
159.
160.
Patient management in Idiopathic Pulmonary Fibrosis (IPF) is largely based on societal guidelines and recommendations. A recent update by the American Thoracic Society (ATS), European Respiratory Society (ERS), Japanese Respiratory Society (JRS) and Latin American Thoracic Association (ALAT) provided updated guidance on the diagnosis and management of IPF, along with recommendations on pharmacologic and non-pharmacologic approaches to patient management. The treatment guidance is based on GRADE criteria, which rates the quality of evidence according to previously published methodology. Here we discuss how to interpret the recent guideline updates and the implications of this guidance for clinical practice. In addition we discuss the assessment and recommendations for a number of pharmacological agents that have been the focus of clinical trials over the past years. Although no single pharmacological agent was recommended by the guidelines committee, we discuss how since then, more recent data have resulted in the approval of pirfenidone in Europe, and preliminary negative findings regarding the safety of a triple therapy regimen consisting of prednisone, azathioprine and N-acetylcysteine have raised the question of whether it is no longer a treatment option. As clinicians, we must interpret the available guidance and recommendations as we consider each individual patient and as we discuss the available clinical data and the patient’s own preferences in our approach to the management of this disease.  相似文献   
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