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951.
Basic Blue 75: a New Stain for Erythroblasts   总被引:2,自引:0,他引:2  
C.I. basic blue 75 in an aqueous alkaline solution stains the nuclei of mature anc immature erythroblasts bright red. Simultane ously, the stain colors the cytoplasm of erythro blasts blue in immature cells and purple in ma ture cells. Colors of the type described were noi found in other normal and abnormal hemato poietic cells.  相似文献   
952.
953.
In contrast to canonical proteases, myelin basic protein (MBP)-Sepharose-purified IgG from multiple sclerosis (MS) and systemic lupus erythematosus (SLE) patients efficiently hydrolyze only MBP, but not many other tested proteins. It was shown that anti-MBP SLE IgGs cleave nonspecific tri- and tetrapeptides with an extremely low efficiency and cannot efficiently hydrolyse longer oligopeptides corresponding to antigenic determinants (AGDs) of HIV-1 integrase. To identify all sites of IgG-mediated proteolysis corresponding to two AGDs of MBP, we have used a combination of reverse-phase chromatography (RPhC), MALDI spectrometry, and TLC to analyze the cleavage products of two (17- and 19-mer) encephalytogenic oligopeptides corresponding to these AGDs. Both oligopeptides contained several clustered major and minor sites of cleavage. The active sites of anti-MBP abzymes are localized on their light chains, while the heavy chains are responsible for the affinity of protein substrates. Interactions of intact globular proteins with both light and heavy chains of abzymes provide high specificity of MBP hydrolysis. The affinity of anti-MBP abzymes for intact MBP was ~10(3)-fold higher than for the oligopeptides. The data suggest that both oligopeptides interact mainly with the light chain of different monoclonal abzymes of total pool of IgGs, which possesses lower affinity for substrates, and therefore, depending on the oligopeptide sequences, their hydrolysis may be less specific.  相似文献   
954.
Stroke-prone spontaneously hypertensive rats (SHRSP/Izm) develop severe hypertension, and more than 95% of them die of cerebral stroke. We showed the vulnerability of neuronal cells of SHRSP/Izm rats. Furthermore, we analyzed the characteristics of SHRSP/Izm astrocytes during a stroke. It is known that the proliferating ability of SHRSP/Izm astrocytes is significantly enhanced compared with those in the normotensive Wistar Kyoto rats (WKY/Izm) strain. Conversely, the ability of SHRSP/Izm astrocytes to form tight junctions (TJ) was attenuated compared with astrocytes from WKY/Izm rats. During the stress of hypoxia and reoxygenation (H/R), lactate production, an energy source for neuronal cells, decreased in SHRSP/Izm astrocytes in comparison with the WKY/Izm strain. Moreover, during H/R, SHRSP/Izm astrocytes decreased their production of glial cell line-derived neurotrophic factor (GDNF) in comparison with WKY/Izm astrocytes. Furthermore, SHRSP/Izm rats decreased production of l-serine, compared with WKY/Izm rats following nitric oxide (NO) stimulation. Additionally, in H/R, astrocytes of SHRSP/Izm rats expressed adhesion molecules such as VCAM-1 at higher levels.It is possible that all of these differences between SHRSP/Izm and WKY/Izm astrocytes are not associated with the neurological disorders in SHRSP/Izm. However, attenuated production of lactate and reduced GDNF production in astrocytes may reduce required energy levels and weaken the nutritional status of SHRSP/Ism neuronal cells. We suggest that the attenuation of astrocytes’ functions accelerates neuronal cell death during stroke, and may contribute to the development of strokes in SHRSP/Izm. In this review, we summarize the altered properties of SHRSP/Izm astrocytes during a stroke.  相似文献   
955.
Osteoarthritis is a common joint disease for which there are currently no disease-modifying drugs available. Degradation of the cartilage extracellular matrix is a central feature of the disease and is widely thought to be mediated by proteinases that degrade structural components of the matrix, primarily aggrecan and collagen. Studies on transgenic mice have confirmed the central role of Adamalysin with Thrombospondin Motifs 5 (ADAMTS-5) in aggrecan degradation, and the collagenolytic matrix metalloproteinase MMP-13 in collagen degradation. This review discusses recent advances in current understanding of the mechanisms regulating expression of these key enzymes, as well as reviewing the roles of other proteinases in cartilage destruction. This article is part of a Special Issue entitled: Proteolysis 50 years after the discovery of lysosome.  相似文献   
956.
The critical periods of axial skeletal development in rats and mice have been well characterized, however the timing of skeletal development in rabbits is not as well known. It is important to have a more precise understanding of this timing of axial skeletal development in rabbits due to the common use of this species in standard nonclinical studies to assess embryo–fetal developmental toxicity. Hydroxyurea, a teratogen known to induce a variety of fetal skeletal malformations, was administered to New Zealand White rabbits as a single dose (500 mg/kg) on individual days during gestation (gestation day,GD 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, or 19) and fetal external, visceral, and skeletal morphology was examined following cesarean sections on GD 29. A wide range of fetal skeletal effects was observed following hydroxyurea treatment, with a progression of malformations from anterior to posterior structures over time, as well as from proximal to distal structures over time. The sensitive window of axial skeletal development was determined to be GD 8 to 13, while disruption of appendicular and cranio‐facial skeletal development occurred primarily from GD 11 to 16 and GD 11 to 12, respectively. The results of this study provide a better understanding of the critical developmental window for different segments of the rabbit skeleton, which will aid in the design of window studies to investigate teratogenicity in rabbits.  相似文献   
957.
The morphogenesis and sequence of ossification and chondrification of skeletal elements of the jaws, and hyoid arch and gill arches of Puntius semifasciolatus are described. These data provide a baseline for further studies and enable comparisons with other described cypriniforms. Some general patterns of ossification in the hyoid arch and branchial arches in cypriniforms were notable. First, the overall development is from anterior to posterior, with the exception of the fifth ceratobranchial bone, which ossifies first. Second, where ossification of iterated elements is sequential, it tends to proceed from posterior to anterior, even when more posterior chondrifications are the smallest in the series. Ossification of the ceratobranchial, epibranchial and pharyngobranchial bones tends to proceed from ventral to dorsal. The comparisons revealed small sets of skeletal elements whose ossification sequence appears to be relatively conserved across cyprinid cypriniforms. Several potentially key timing changes in the ossification sequence of the jaws, hyoid arch and gill arches were identified, such as the accelerated timing of ossification of the fifth ceratobranchial bone, which may be unique to cypriniforms.  相似文献   
958.
Plant genome possesses over 100 protein phosphatase (PPase) genes that are key regulators of signal transduction via phosphorylation/dephosphorylation event. Here we report a comprehensive functional analysis of protein serine/threonine, dual-specificity and tyrosine phosphatases using recombinant PPases produced by wheat cell-free protein synthesis system. Eighty-two recombinant PPases were successfully produced using Arabidopsis full-length cDNA as templates. In vitro PPase assay was performed using phosphorylated myelin basic protein as substrate. Among the AtPPases examined, 26 serine/threonine, three dual-specificity and one tyrosine PPases exhibited catalytic activity, including 20 serine/threonine and one dual-specificity PPases that showed in vitro activities for the first time. Our study demonstrates genome-wide biochemical analysis of AtPPases using wheat cell-free system, and provides new information and insights on enzyme activities.

Structured summary of protein interactions

PTP1dephosphorylatesMBP by phosphatase assay (View interaction).AtPP2CdephosphorylatesMBP by phosphatase assay (View interaction).POLTEdephosphorylatesMBP by phosphatase assay (View interaction).TOPP8dephosphorylatesMBP by phosphatase assay (View interaction).HAB1dephosphorylatesMBP by phosphatase assay (View interaction).ABI2dephosphorylatesMBP by phosphatase assay (View interaction).At1g34750dephosphorylatesMBP by phosphatase assay (View interaction).At1g43900dephosphorylatesMBP by phosphatase assay (View interaction).At3g15260dephosphorylatesMBP by phosphatase assay (View interaction).At5g53140dephosphorylatesMBP by phosphatase assay (View interaction).At1g18030dephosphorylatesMBP by phosphatase assay (View interaction).At3g06270dephosphorylatesMBP by phosphatase assay (View interaction).At2g25070dephosphorylatesMBP by phosphatase assay (View interaction).At3g02750dephosphorylatesMBP by phosphatase assay (View interaction).At5g10740dephosphorylatesMBP by phosphatase assay (View interaction).at4g26080dephosphorylatesMBP by phosphatase assay (View interaction).At4g28400dephosphorylatesMBP by phosphatase assay (View interaction).At5g06750dephosphorylatesMBP by phosphatase assay (View interaction).At4g31860dephosphorylatesMBP by phosphatase assay (View interaction).At3g17250dephosphorylatesMBP by phosphatase assay (View interaction).At4g38520dephosphorylatesMBP by phosphatase assay (View interaction).At3g05640dephosphorylatesMBP by phosphatase assay (View interaction).At5g66080dephosphorylatesMBP by phosphatase assay (View interaction).At1g79630dephosphorylatesMBP by phosphatase assay (View interaction).At2g30170dephosphorylatesMBP by phosphatase assay (View interaction).At5g24940dephosphorylatesMBP by phosphatase assay (View interaction).  相似文献   
959.
Caccamese S  Bianca S  Carter GT 《Chirality》2009,21(6):569-577
A direct liquid chromatographic enantioselective separation of venlafaxine and 11 analogs was obtained in the normal phase mode using Chiralpak AD. For some compounds, a comparison between the enantioseparation using coated and immobilized amylose tris(3,5-dimethylphenylcarbamate) chiral stationary phases (Chiralpak AD and Chiralpak IA, respectively) was made. The best separations were achieved on Chiralpak AD with ethanol as alcoholic modifier in a mobile phase made basic by DEA addition: separation factor ranges between 2.08 and 1.15 and resolution factor between 7.0 and 1.0. Using the same CSP and 2-propanol doped with TFA as acidic modifier, 10 compounds were enantioseparated with separation factor ranging between 1.40 and 1.04 and resolution factor between 3.1 and 0.3. The use of ethanol as alcoholic modifier also has the advantage of better solubility of the compounds in the mobile phase. The nature of the substituent (electron donating or withdrawing) affects in general the separation factor. A memory effect that involves a long equilibration time of the CSP is present when switching from an acidic mobile phase to a basic one.  相似文献   
960.
Jansen LA  Wall S 《Bioethics》2009,23(3):172-182
In this paper, we defend the ethics of clinical research against the charge of paternalism. We do so not by denying that the ethics of clinical research is paternalistic, but rather by defending the legitimacy of paternalism in this context. Our aim is not to defend any particular set of paternalistic restrictions, but rather to make a general case for the permissibility of paternalistic restrictions in this context. Specifically, we argue that there is no basic liberty-right to participate in clinical research and that considerations of distributive fairness justify some paternalistic protections of research subjects.  相似文献   
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