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1.
Immunological reactions of bloodstains of human and animals to anti-human serum were analysed quantitatively to determine which technique is the most effective to differentiate human bloodstains from those of animals. The lower threshold of counter-electrophoresis was 10-25 micrograms protein/ml and increased only slightly with increasing age of the bloodstains, while that of the ring test and immunodiffusion decreased greatly. In counter-electrophoresis, absorption of anti-human serum by Japanese monkey serum resulted in a marked decrease in the cross reaction with animals, and still showed no change in the lower threshold for human samples. The present results show that counter-electrophoresis is especially useful for the identification of human bloodstains.  相似文献   

2.
The platelet glycoprotein Ib-IX-V complex plays critical roles in adhering platelets to sites of blood vessel injury and in platelet aggregation under high fluid shear stress. The complex is composed of four membrane-spanning polypeptides: glycoprotein (GP) Ibalpha, GP Ibbeta, GP IX, and GP V. Glycoprotein Ibalpha contains a binding site for von Willebrand factor through which it mediates platelet adhesion; GP V is required for the complex to bind thrombin with high affinity; and both GP Ibbeta and GP IX are necessary for efficient plasma membrane expression of the complex. To further define the roles of the individual polypeptide subunits in the biosynthesis and intracellular transport of the GP Ib-IX-V complex, we studied full and partial complexes expressed in heterologous mammalian cells. We found that the full complex was formed within minutes in the endoplasmic reticulum before being transported into the Golgi cisternae. Approximately 160 min were required for the complex to be fully processed and to appear on the plasma membrane. About 25% of GP Ibalpha expressed as part of either a GP Ib-IX complex or a GP Ib-IX-V complex was degraded through a nonlysosomal pathway. Over 60% of GP Ibalpha, however, was degraded when it was expressed in partial complexes with only GP Ibbeta or GP IX. The increased degradation was blocked by treating cells either with brefeldin A to prevent the transport of proteins from the endoplasmic reticulum to the Golgi or with lysosomal inhibitors, indicating that GP Ibalpha expressed in partial complexes was targeted to the lysosomes for degradation. These results indicate that the presence of both GP Ibbeta and GP IX, but not the presence of GP V, is required for efficient processing and targeting of GP Ibalpha to the plasma membrane. Absence of either GP Ibbeta or GP IX increased the rate of GP Ibalpha degradation, providing an explanation for why mutation of their genes leads to deficient GP Ibalpha expression and platelet adhesion in Bernard-Soulier syndrome, the deficiency disorder of the complex.  相似文献   

3.
4.
We investigated two unrelated patients with Bernard-Soulier syndrome (BSS) by performing molecular and genetic analysis. A flow cytometric and immunoblotting analysis showed GP Ib alpha to be absent from the platelet membrane of both patients. Other glycoproteins that formed GP Ib/IX/V complex were present on the platelets, but in decreased amounts. Therefore, GP Ib alpha gene from both cases was sequenced after PCR amplification and subcloning. We identified a homozygous mutation of a dinucleotide deletion within the TGTG repeat at cDNA number 972 to 975 in GP Ib alpha gene from Case 1. In Case 2, compound heterozygosity was demonstrated in GP Ib alpha gene; an insertion of a single base (T) at cDNA number 1,418 in one allele, and a deletion of a single base (A) within the 7-adenine repeat at cDNA number 1,438 to 1,444 in another allele. The three new mutations in both patients appeared to cause a frameshift, which created a new termination codon shortly thereafter, and thus lead to a GP Ib alpha deficiency on the platelet membrane. Truncated mutant proteins could be detected in the plasma and platelets of Case 2, but not of Case 1. According to these findings, it is thus supposed that the properties and conformation of additional COOH-terminal peptides, which were supposedly synthesized as results of the mutations, may have an important role on the processing of mutant GP Ib alpha in megakaryocytes and platelets.  相似文献   

5.
Immunocytochemical methods to determine the ABO blood group of each blood of mixed bloodstains have been developed. Mixed bloodstains were made on surgical blades and a cedar board. The blades were dipped into blood and then dipped into blood of a different group at intervals of 30, 20, 15, 10 and 5 s. Two drops of blood were dropped on a cedar board and then two drops of blood of a different group were dropped there at the same intervals. The bloodstains were dried for a week. The blood samples were removed from the blades or the cedar board and processed according with a routine histological method. Three serial thin sections were obtained. After deparaffinization, the sections were treated in papain solution for 2 h at 36 degrees C, to unmask antigenic sites on red cell membranes. The labeled streptavidin-biotin (LSAB) and peroxidase-anti-peroxidase (PAP) methods were used to detect A and B antigens, and an indirect immunocytochemical method for H antigen. These immunocytochemical methods showed specific immunologic reactions and allowed determination of the blood group of each blood of mixed bloodstains. Further, these methods indicated a possibility to determine who was stabbed first, in cases where two or more victims were stabbed with a single knife.  相似文献   

6.
The vitronectin receptor (VnR or alpha v beta 3) belongs to the cytoadhesin subclass of the integrin family. This subclass consists of two receptors which have the beta 3 subunit in common: GP IIb-IIIa complexes (or alpha IIb beta 3) and VnR. We report the subcellular distribution of VnR within human platelets as determined by immunogold staining of ultrathin frozen sections and transmission electron microscopy. Monoclonal antibodies directed against: (i) the alpha v subunit (LM142, AMF7, CLB-706), or (ii) an epitope specific to the complex (LM609) were used. Although VnR is present on platelets, it is a minor component. We therefore first compared several different staining procedures to detect this integrin. Optimal localization of VnR was obtained using a multistep procedure in which biotinylated anti-mouse IgG and a monoclonal anti-biotin antibody provided staining enhancement. Results showed that although present on the surface, alpha v beta 3 was mostly detected in internal membrane systems including those of alpha-granules. Occasionally, platelet sections showed special vesicular structures covered by gold particles. These were often localized at the edge or immediately under the plasma membrane and their origin remains unclear. An internal pool of alpha v beta 3 was confirmed by flow cytometry and by using platelets from a patient with type I Glanzmann's thrombasthenia arising from a GP IIb gene defect. We also investigated the presence of VnR in megakaryocytes (MK) obtained from normal human bone marrow. A fluorescence study showed VnR in small MK with unilobulated nuclei, suggesting that synthesis of this integrin occurs early during megakaryocytopoiesis. In mature cells, VnR expression had decreased relative to GP IIb-IIIa, although intracellular staining was present in EM and alpha-granules were again labelled.  相似文献   

7.
Von Willebrand factor (vWF) is synthesized by human endothelial cells and megakaryocytes as a large precursor, the pre-provWF, which is finally cleaved into the propolypeptide of vWF (pp-vWF) and the mature vWF. We have purified in parallel the pp-vWF and the GP IIb-IIIa from porcine platelets. The N-terminus comparative analysis of porcine pp-vWF with respect to other species revealed more than a 75% and 65% homology with the bovine and human pp-vWF, respectively. Purified pp-vWF inhibited collagen-induced platelet aggregation in porcine platelet rich plasma (PRP) and specifically binds to collagen. Polyclonal antibody pabBp19 against the purified protein was prepared and characterized by ELISA, Western-blot and immunocytochemistry. The distribution of pp-vWF in soluble and membrane fractions from pig platelets has been performed by immunolabeling detection. pabBp19 did not blot human platelet lysates but human pp-vWF was detectable using the antibody Frieda 013091. Cell distribution and quantification studies of human and porcine platelet pp-vWF showed that the protein exists in the soluble and membrane fractions and its pattern is similar in both species.  相似文献   

8.
Fatty acids were estimated in plasma and red blood cell membrane in rats, rabbits, dogs and humans. The fatty acid pattern of plasma and red blood cell membrane was similar in all species and humans with little exceptions. C18:2 was higher in plasma than red blood cell membrane whereas C20:4 was higher in red blood cell membrane than plasma except rabbit. C18:2 was high in rabbit red blood cell membrane when compared to others. Dog was exceptionally very low in C18:2 and high in C20:4 in red blood cell membrane whereas rabbit was low in C20:4 and high in C18:2. 22-Carbon fatty acids showed some variation. Among 22-carbon fatty acids C22:6 was found highest in human red blood cell membrane, with quite high amounts in rat and rabbit but not in dog. Rats were closest to human in their fatty acid patterns.  相似文献   

9.
The effects of zero magnetic field on human VH-10 fibroblasts and lymphocytes were studied by the method of anomalous viscosity time dependencies (AVTD). A decrease of about 20% in the AVTD peaks was observed within 40 to 80 min of exposure of fibroblasts. This decrease was transient and disappeared 120 min after beginning of exposure. Similar kinetics for the effect of zero field was observed when cells were exposed 20 min and then kept at an ambient field. A 20% decrease of the AVTD peaks (p < 0.005 to 0.05) 40 to 70 min after 20 min exposure to zero field was reproduced in four independent experiments (out of four) with human lymphocytes from the same healthy donor. Contrary to the effects of zero field, irradiation of lymphocytes or fibroblasts with gamma-rays resulted in significant increase of the AVTD peaks immediately after irradiation. We concluded that zero field and gamma-rays caused hypercondensation and decondensation of chromatin, correspondingly. The effect of ethidium bromide served as a positive control and supported this conclusion. The effects of zero field on human lymphocytes were more significant in the beginning of G1-phase than in G0-phase. Thus, human fibroblasts and lymphocytes were shown to respond to zero magnetic field.  相似文献   

10.
The detection of restriction fragment length polymorphisms (RFLP) (1) in DNA extracted from forensic samples remains impossible in a significant number of cases due to deterioration and contamination of the biological material and the extremely low quantities of DNA isolated. The polymerase chain reaction (PCR) is a recent and particularly convenient method for analysing and typing very small amounts (10-20 ng) of degraded human DNA. DNA analysis at the level of a few cells present in forensic samples such as bloodstains, semen stains, vaginal swabs and head hair bulbs now appears possible using DNA amplification. A PCR protocol was adapted to simultaneously amplify a Y-specific DNA repeat sequence from the DYZ1 locus and an X-specific DNA repeat sequence from the DXS424 locus. The co-amplified Y-specific DNA fragment (102 bp) and X-specific DNA fragments (181-199 bp) were visualized on an ethidium bromide-stained 4% agarose gel. The male or female type of the amplified DNA extracted from blood samples, bloodstains, semen stains, vaginal swabs, brain tissue and 1, 2, 5, or 10 head hair bulbs was determined.  相似文献   

11.
Open reading frame 3 (ORF3) of the genome of porcine reproductive and respiratory syndrome virus (PRRSV), Quebec strain IAF-Klop, was reverse-transcribed and cloned into the procaryotic expression vector pGEX-4T-1, then subcloned into the eucaryotic expression vector pAdCMV5 which was used as a shuttle vector to generate a replication-defective recombinant adenovirus. The procaryotic GST-ORF3 recombinant fusion protein was used to raise a monospecific antiserum in rabbits. By Western-immunoblotting with PRRSV-infected cell extracts, the ORF3 encoded protein had an estimated molecular mass (M(r)) of 42 kDa, similar to that of the protein expressed by the adenovirus vector. Endoglycosidase F digestion showed that the ORF3 encoded protein occurs in an highly glycosylated form (GP3) in the infected MARC-145 cells. Pulse-chase and radioimmunoprecipitation experiments revealed that the GP3 protein was present in amounts equivalent to those of the N, M, and GP5 proteins in the infected cells, whereas no GP3 could be detected in purified virions. During the first 30 min of chase, the GP3 undergoes a gradual downward shift of its apparent M(r), thought to result from trimming of the mannose-rich glycan structures. Tested convalescent pig sera that were found to be seropositive to PRRSV by indirect immunofluorescence reacted positively with the recombinant GST-ORF3 fusion protein by immunoblotting. Data indicated that the ORF3 protein of the Quebec reference strain of PRRSV is a highly glycosylated and antigenic protein, which is nonstructural.  相似文献   

12.
The role of antiphospholipid antibodies in the pathogenesis of the thrombocytopenia observed during primary antiphospholipid antibody syndrome (APAS) and systemic lupus erythematosus (SLE) remains controversial. We have used the MAIPA test to examine the frequency and specificity of anti-platelet antibodies directed against the major platelet membrane glycoproteins (GP IIb-IIIa, GP Ib-IX, GP Ia-IIa and GP IV) in patients where SLE and APAS were associated or not with thrombocytopenia. Results were compared with a series of 26 ITP patients, 46% of whom were shown to possess anti-platelet antibodies directed against one or more of the platelet surface glycoproteins. When APAS was associated with thrombocytopenia, 7/10 patients possessed antibodies against GP IIb-IIIa and/or GP Ib-IX. For SLE patients with thrombocytopenia, 6/10 patients were shown to have antiplatelet antibodies against GP IIb-IIIa, GP Ib-IX or GP IV. In contrast, for APAS (n=11) and SLE patients (n=11) without thrombocytopenia, only one patient had an antibody directed against GP IIb-IIIa and one patient had an antibody to GP IV. Our results suggest that antibodies directed against major platelet membrane glycoproteins may play a role in the thrombocytopenia that is seen during SLE and APAS.  相似文献   

13.
A novel fucosyltransferase (cFTase) activity has been enriched over 10(6)-fold from the cytosolic compartment of Dictyostelium based on transfer of [3H]fucose from GDP-[3H]fucose to Galbeta1,3 GlcNAc beta-paranitrophenyl (paranitrophenyl-lacto-N-bioside or pNP-LNB). The activity behaved as a single component during purification over DEAE-, phenyl-, Reactive Blue-4-, GDP-adipate-, GDP-hexanolamine-, and Superdex gel filtration resins. The purified activity possessed an apparent Mr of 95 X 10(3), was Mg2+-dependent with a neutral pH optimum, and exhibited a Km for GDP-fucose of 0.34 microM, a Km for pNP-LNB of 0.6 mM, and a Vmax for pN-P-LNB of 620 nmol/min/mg protein. SDS-polyacrylamide gel electrophoresis analysis of the Superdex elution profile identified a polypeptide with an apparent Mr of 85 X 10(3), which coeluted with the cFTase activity and could be specifically photolabeled with the donor substrate inhibitor GDP-hexanolaminyl-azido-125I-salicylate. Based on substrate analogue studies, exoglycosidase digestions, and co-chromatography with fucosylated standards, the product of the reaction with pNP-LNB was Fucalpha1, 2Galbeta1,3GIcNAcbeta-pNP. The cFTase preferred substrates with a Galbeta1,3linkage, and thus its acceptor substrate specificity resembles the human Secretor-type alpha1,2- FTase. Afucosyl isoforms of the FP21 glycoprotein, GP21-I and GP21-II, were purified from the cytosol of a Dictyostelium mutant and found to be substrates for the cFTase, which exhibited an apparent K(m) of 0.21 microM and an apparent V(max) of 460 nmol/min/mg protein toward GP21-II. The highly purified cFTase was inhibited by the reaction products Fucalpha1,2Galbeta1,3GlcNAcbeta-pNP and FP21-II. FP21-I and recombinant FP21 were not inhibitory, suggesting that acceptor substrate specificity is based primarily on carbohydrate recognition. A cytosolic location for this step of FP21 glycosylation is implied by the isolation of the cFTase from the cytosolic fraction, its high affinity for its substrates, and its failure to be detected in crude membrane preparations.  相似文献   

14.
Ante- and post-mortem bloodstains prepared from the blood of volunteers and corpses were analysed for ATP and its related compounds by reversed-phase high-performance liquid chromatography (HPLC). The results showed that (1) ATP was present in a large amount in antemortem bloodstains but not in postmortem stains, (2) AMP, adenosine, inosine, hypoxanthine, xanthine and uracil either were not detected or were detected in smaller amounts in antemortem than in postmortem bloodstains, and (3) ADP was present in both ante- and post-mortem bloodstains. These differences suggest that quantitation of these compounds may be useful in identifying whether bloodstains are ante- or post-mortem.  相似文献   

15.
A study was conducted to evaluate coronal microleakage of Super EBA and Ketac-Endo when used as sealers with single-cone gutta-percha (GP) root canal obturation. The root canals of 24 extracted human teeth were instrumented with flared preparations to a minimum #40 master apical file size. Ten teeth were obturated with a single GP cone and Super EBA as the sealer and ten teeth were obturated with a single GP cone and Ketac-Endo as the sealer. Four teeth were used as controls. Salivary bacterial microleakage studies were conducted to determine whether these sealers could prevent coronal microleakage through the root canal in the absence of a coronal tooth restoration. There was no bacterial penetration through the apical foramen for either sealer tested during the 60-day test period.  相似文献   

16.
We have previously described two human cold agglutinin MoAbs 216 and A6(H4C5), that are derived from the VH4-34 (VH4.21) gene that bind specifically to a cell surface ligand on human B lymphocytes. In this study, we report that binding of 216 and A6(H4C5) leads to rapid killing of target B cells. This complement-independent cytotoxicity was measured by three independent assays, cell viability dye uptake on FACS, 3H-thymidine uptake, and the 3(4,5)-dimethylthiazol-2,5-diphenyl tetrazolium bromide (MTT) assay. Cytotoxicity was specific for CD20+ mononuclear cells in human spleen and peripheral blood. The MoAbs were also cytotoxic to human B cell lines Nalm-6, OCI-LY8, Arent and SUP-B8, but not to T cell lines HuT 78 and PEER. As observed by scanning electron microscopy, membrane pores were formed within 15 min of exposure to the MoAbs. Cytotoxic activity was dependent on MoAb concentration and temperature of exposure. Killing with greater at 4 degrees C than 37 degrees C. Sodium azide and EDTA did not block the cytotoxic activity. No DNA fragmentation typical of apoptosis was observed. This rapid cytotoxic activity, independent of physiologic cellular process and independent of complement, suggests a novel mechanism of all death via membrane perturbations.  相似文献   

17.
Glutamine plays an important role in fetal nutrition. This study explored the transport of [3H]glutamine into apical and basal predominant membrane vesicles derived from rat and human placenta. Na+-dependent glutamine transport was present in both apical and basal predominant vesicles derived from 20- and, to a lesser degree, 14-day gestation rat placenta. Amino-acid transport systems A, ASC-like, B(o,+) (in apical membrane vesicles) and, perhaps, y+L were involved in Na+-dependent glutamine transport. Na+-dependent glutamine uptake into human placental microvillus and basolateral membrane vesicles also occurred via several distinct transport activities. Glutamine transport via system N was not detected in either rat or human placental preparations. Na+-dependent glutamine transport in the rat was more pronounced in basal as compared to apical membrane vesicles. Conversely, in the human preparations, activity was significantly higher in microvillus as compared to basolateral membrane vesicles. It is concluded that Na+-dependent glutamine transport occurs through a variety of transport agencies in both the rat and human placenta. Transport varies with ontogeny and between species.  相似文献   

18.
We performed 2 studies aimed at developing a frozen platelet panel suitable for platelet cross-matching. The stability of the most important platelet membrane glycoproteins and the reactivity of antigens of the human platelet antigen (HPA) and of the human leukocyte antigen (HLA) systems were evaluated with the platelet suspension immunofluorescence test (PSIFT) in a panel of platelets frozen in microplates with 6% dimethylsulfoxide. In study No. 1 we evaluated platelet reaction with a broad-spectrum weak anti-HLA and a potent anti-HPA-1a antiserum and the expression of glycoproteins Ib and IIb/IIIa complex on platelet membrane before freezing and after 0.5, 1, 2, 3, 4, 5, 6 and 12 months of storage at -80 degrees C. In study No. 2 we examined platelet reactivity with anti-HPA-1b, -HPA-2a, -HPA-3a, -HLA-A2, -HLA-A3 of platelets stored frozen for 12 months in parallel with fresh platelets from the same donors. Study No. 1 showed that glycoprotein expression was stable and that the weak anti-HLA and the potent anti-HPA-1a antibodies were clearly detected during 12 months at -80 degrees C. Of the 35 paired PSIFT performed in study No. 2 with fresh and frozen/thawed platelets incubated with anti-HPA-1b, -HPA-2a, -HPA-3a, -HLA-A2, -HLA-A3 antisera and AB serum, concordant reactions were obtained in all cases with the exception of 1 case of HLA-A3-positive platelets incubated with anti-HLA-A3 antiserum, that was reactive with frozen/thawed platelets but nonreactive with fresh platelets from the same donor.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

19.
Yeast-phase cells of Histoplasma capsulatum were challenged with amphotericin B, and membrane perturbation was monitored by K+ efflux. Suspensions of washed cells readily absorbed about 1.12 microgram of amphotericin B per mg (dry weight) and further nonspecific sites were also apparent. The dose-response curve for initial rate of K+ efflux was sigmoidal within the range 0.1 to 1.0 microgram of amphotericin B per ml. A fungistatic concentration of amphotericin B (0.3 microgram/ml) evoked an efflux of 85 to 90% K+ from the cells within 15 min, but cell viability decreased only 13% (yeast phase) or 33% (transformed to mycelial units). Ultrastructural changes in treated cells were detected within 5 min, and the hallmark was expansion of vacuoles during the 1-h monitoring period. In contradistinction to a previous report, the appearance of the protoplasmic membrane was not altered by fungistatic concentration. When treated cells were returned to a fresh growth medium, there was a pronounced lag (20 h). During this apparent recovery phase, the large vacuoles fragmented and returned to normal size. It is proposed that vacuoles of H. capsulatum act as a spatial buffer of considerable survival value to stressed cells.  相似文献   

20.
Mice, rats and guinea pigs were exposed to phosgene (COCl2), a highly irritating and oxidizing gas. Animals were exposed to 87 mg/m3 phosgene for 20 min in a whole-body exposure chamber. Within 55-65 minutes after the start of exposure, plasma was scanned spectrophotometrically from 200-600 nm. A distinct and significant increase in area under the curve in the Soret band region at 413 nm was observed in plasma from phosgene-exposed animals when compared with air-exposed controls in all three species. These peaks were consistent with hemoglobin, an indication that the integrity of the erythrocyte membrane had been compromised by exposure. An erythrocyte osmotic fragility assay on blood from mice exposed to phosgene indicated that 30% less NaCl was needed to cause 50% hemolysis compared to air-exposed mice. These results suggest a new mechanism of phosgene-induced acute lung injury that may be linked, in part, to a direct attack on the erythrocyte membrane.  相似文献   

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