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61.
62.
A xenobiotics-inactivating hemoprotein related to the class of pharmacologically active compounds (cholinolytics) was detected in rat blood. Ammonium sulphate fractionation, DEAE cellulose chromatography and gel filtration on Sephadex G-75 resulted in 750-fold purification of the protein; its Mr = 73 000-80 000. Multiple injections of the protein to experimental animals led to a 2-3-fold increase of the protein content in the blood.  相似文献   
63.
64.

Background

Angiotensin-converting enzyme (ACE), which metabolizes many peptides and plays a key role in blood pressure regulation and vascular remodeling, as well as in reproductive functions, is expressed as a type-1 membrane glycoprotein on the surface of endothelial and epithelial cells. ACE also presents as a soluble form in biological fluids, among which seminal fluid being the richest in ACE content - 50-fold more than that in blood.

Methods/Principal Findings

We performed conformational fingerprinting of lung and seminal fluid ACEs using a set of monoclonal antibodies (mAbs) to 17 epitopes of human ACE and determined the effects of potential ACE-binding partners on mAbs binding to these two different ACEs. Patterns of mAbs binding to ACEs from lung and from seminal fluid dramatically differed, which reflects difference in the local conformations of these ACEs, likely due to different patterns of ACE glycosylation in the lung endothelial cells and epithelial cells of epididymis/prostate (source of seminal fluid ACE), confirmed by mass-spectrometry of ACEs tryptic digests.

Conclusions

Dramatic differences in the local conformations of seminal fluid and lung ACEs, as well as the effects of ACE-binding partners on mAbs binding to these ACEs, suggest different regulation of ACE functions and shedding from epithelial cells in epididymis and prostate and endothelial cells of lung capillaries. The differences in local conformation of ACE could be the base for the generation of mAbs distingushing tissue-specific ACEs.  相似文献   
65.
To investigate the dynamic cellular response to a condition change, selective labeling of the nascent proteome is necessary. Here, we report a method combining click chemistry protein labeling with 2D DIGE. To test the relevance of the method, we compared nascent proteomes of actively growing bacterial cells with that of cells exposed to protein synthesis inhibitor, erythromycin. Cells were incubated with methionine analog, homopropargyl glycin, and their nascent proteome was selectively labeled with monosulfonated neutral Cy3 and Cy5 azides specially synthesized for this purpose. Following fluorescent labeling, the protein samples were mixed and subjected to standard 2D DIGE separation. The method allowed us to reveal a dramatic reduction of newly synthesized proteins upon erythromycin treatment, while the total proteome was not significantly affected. Additionally, several proteins, whose synthesis was resistant to erythromycin, were identified.  相似文献   
66.
Journal of Evolutionary Biochemistry and Physiology - The study aimed to reveal neurophysiological markers of the effects of transcranial direct current stimulation (tDCS) in children with speech...  相似文献   
67.

Background

Combination of erlotinib and bevacizumab is a promising regimen in advanced non-squamous non-small-cell lung cancer (NSCLC). We are conducting a single arm phase II trial which aims to evaluate the efficacy and safety of this regime as a second- or third-line chemotherapy.

Methods

Key eligibility criteria were histologically or cytologically confirmed non-squamous NSCLC, stage III/IV or recurrent NSCLC not indicated radical chemoradiation, prior one or two regimen of chemotherapy, age 20 years or more, and performance status of two or less. The primary endpoint is objective response rate. The secondary endpoints include overall survival, progression-free survival, disease control rate and incidence of adverse events. This trial plans to accrue 80 patients based on a two-stage design employing a binomial distribution with an alternative hypothesis response rate of 35% and a null hypothesis threshold response rate of 20%. A subset analysis according to EGFR mutation status is planned.

Discussion

We have presented the design of a single arm phase II trial to evaluate the efficacy and safety of combination of bevacizumab and erlotinib in advanced non-squamous NSCLC patients. In particular we are interested in determining the merit of further development of this regimen and whether prospective patient selection using EGFR gene is necessary in future trials.

Trial registration

This trial was registered at the UMIN Clinical Trials Registry as UMIN000004255 (http://www.umin.ac.jp/ctr/index.htm).  相似文献   
68.
Influenza A viruses play a significant role in human and animal pathologies that cause epidemics and epizootics. Therefore, the development of new anti-flu drugs has become increasingly urgent. Deoxyribozymes can be considered as promising antiviral agents due to their ability to efficiently cleave RNA molecules with high specificity. In this study, a number of genomic sequences of the most relevant influenza A virus subtypes, i.e., H5N1, H3N2, and H1N1, were analyzed. Conserved regions were revealed in the five least variable segments of the fragmented viral RNA genome, and potential sites of their cleavage with 10–23 deoxyribozymes were determined. We designed and synthesized 46 virus-specific 33-mer deoxyribozymes with the general structure of 5′N8AGGCTAGCTACAACGAN9. Screening of the antiviral activity of these agents in combination with lipofectin on the Madin-Darby Canine Kidney cells infected with highly pathogenic avian influenza virus A/chicken/Kurgan/05/2005(H5N1) revealed 17 deoxyribozymes that suppressed the titer of virus cytopathicity by more than 2.5 logTCID50/mL (i.e. the neutralization index of the virus was more than 300), five of which suppressed the virus titer by a factor of 1000 or more. The most active deoxyribozymes appeared to be specific to segment 5 of the influenza A virus genome, which encoded NP nucleoprotein.  相似文献   
69.
Currently, neutron capture therapy is a promising cancer treatment. This method is based on the reaction of thermal neutron capture by some nonradioactive elements (e.g., Gd157), which results in the sub-sequent emission of electrons and gamma rays. An effective instrument for delivering gadolinium into tumor tissue are “rigid” nanostructures (NSs) based on double-stranded DNA complexes with gadolinium (NS-Gd). The local concentration of Gd in these nanostructures may reach 40%. To optimize the process of neutron capture therapy, it is very important to investigate possible mechanisms of the penetration of NS-Gd particles into tumor cells. In this work, the dynamics of interaction between NS-Gd and cultivated Chinese hamster ovary cells (CHO) was studied by confocal and electron microscopy. NS-Gd were shown to be able to enter CHO cells. This process started after about 1 h of incubation. After 6 h, NS-Gd particles were detected in almost all cells. A further increase in the incubation time did not lead to significant changes in cell morphology, although the amount of NS-Gd inside cells continued to increase. The plasma membranes of the cells remained intact. Once entering the cells, NS-Gd particles remained there for a long time. The data show that NS-Gd has relatively low toxicity and suggest that the presence of NS-Gd in tumor cells does not prevent their division. The data are important for improving the efficiency of the method of neutron-capture therapy.  相似文献   
70.
Vegetatively expressed insecticidal proteins (VIPs) produced by Bacillus thuringiensis fall into several classes of which the third, VIP3, is known for their activity against several key Lepidopteran pests of commercial broad acre crops and because their mode of action does not overlap with that of crystalline insecticidal proteins. The details of the VIP3 structure and mode of action have remained obscure for the quarter century that has passed since their discovery. In the present article, we report the first crystal structure of a full‐length VIP3 protein. Crystallization of this target required multiple rounds of construct optimization and screening—over 200 individual sequences were expressed and tested. This protein adopts a novel global fold that combines domains with hitherto unreported topology and containing elements seemingly borrowed from carbohydrate‐binding domains, lectins, or from other insecticidal proteins.  相似文献   
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