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31.
32.
Summary.  In this work we present evidence that the homologous peptides IHSMNSTIL and IHSMNSSIL derived from L1 HPV-16 and 18 proteins respectively, and with high specificity for the allele HLA-B*3901, according with an algorithm prediction program, induced T cell stimulation in patients with advanced cervical cancer positive for HPV-16 or 18 infection and for the HLA-B*3901 allele. Interestingly, T lymphocytes derived from a patient with HPV-18 infection and stimulated with the peptide IHSMNSTIL were capable to kill a cervical cancer cell line named Rova, derived from the tumor of the same patient. In addition, the cytotoxic activity was strongly increased when this cell line was previously treated with hrIFN-γ. These results suggest that the CTL immune response to L1 HPV-16 and 18 protein derived epitopes is maintained in patients with advanced cervical cancer within specific alleles, and opens the possibility that homologous epitopes may be used in the generation of prophylactic vaccines for cervical tumors bearing different HPV-types. Received March 4, 2002; accepted May 20, 2002  相似文献   
33.
Vaccinia virus propagated in rotated cultures of RK13 cells was purified by sucrose density gradient zonal centrifugation. The purified virus was dissociated with sodium dodecyl sulfate end its protein composition analyzed by polyacrylamide gel electrophoresis. The protein composition of the virion envelope, isolated by the non-ionic detergent Nonidet P-40, was also determined.  相似文献   
34.
Many data suggest involvement of inflammation in neurodegeneration. However, the exact mechanisms of this cooperation are poorly understood. We have previously shown that induction of inflammatory reaction, both before and after injury of the striatum, affects regeneration of dopaminergic neurons. In the present research we studied the role of inflammatory reaction in non-injured striatum. We used myelin oligodendrocyte glycoprotein (MOG) 35-55 in complete Freund's adjuvant (CFA) to elicit experimental autoimmune encephalomyelitis (EAE) mice model. As determined by HPLC, striatal dopamine (DA) and serotonin levels in mice treated with either MOG 35-55 in CFA or CFA alone were significantly higher compared to vehicle-treated controls on 13th day after induction. The ratio of homovanilic acid/dopamine (HVA/DA) and 3, 4 dihydroxyphenylacetic acid/dopamine (DOPAC/DA) were significantly lower in the MOG and CFA groups on 13th day, indicating decreased DA metabolism. Noradrenaline (NA) concentration did not differ between groups. Moreover, the striatal mRNA IL-1beta and TNF-alpha levels were elevated during induction phase of EAE in both groups, as determined by RT-PCR. Our data indicate regulatory connection between dopaminergic and immune systems.  相似文献   
35.
Some intrinsic neurons of the guinea-pig heart contain substance P   总被引:1,自引:0,他引:1  
Whole-mount preparations of the posterior wall of the atria of the guinea pig heart containing intrinsic ganglion cells and nerve plexuses were stained for substance P-like immunoreactivity by the peroxidase-antiperoxidase method. Substance P-like nerve fibres are present as pericellular baskets around most, but not all, of the neuronal cell bodies, and are also found in the connecting nerve bundles, as perivascular nerve plexuses and in the myocardium and pericardium. The majority of ganglion cell bodies are negative for substance P, as reported previously, but we describe for the first time, a small subpopulation of intrinsic neuronal cell bodies which show immunoreactivity for substance P. Therefore, not all cardiac substance P nerves are extrinsic afferent fibres. At present, the physiological role of intrinsic substance P neurones is not clear.  相似文献   
36.
Inositol is an essential precursor for the formation of glycosyl-phosphatidylinositol (GPI)-anchors found in the majority of surface molecules in trypanosomatids, in addition to its requirement for phoshatidylinositol signal transduction pathways. In Leishmania donovani, high-affinity inositol transport is catalyzed by the active myo-inositol/H+ transporter MIT, which is driven by a proton gradient across the parasite membrane. We have characterized the substrate specificity and pharmacology of L. donovani MIT in vitro and in promastigote cultures. High substrate specificity of myo-inositol transport was shown in competition studies with 14 different monosaccharides and MIT function was unaffected by the structurally similar pentose sugars or hexoses. L-Fucose and D-xylose, both inhibitors of the Na+-dependent inositol transport system in the human host, did not affect MIT transport function in the parasite. Competition studies with eight different inositol isomers revealed that proton bonds between the C-2, C-3 and C-5 hydroxyl groups of myo-inositol and the transporter protein played a critical role for substrate recognition, and the C-3 hydroxyl oxygen appears to act as an electron donor to form an H-bond with a positive charge of the MIT permease. The cytotoxic inositol analogue 3-fluoro-myo-inositol was recognized by MIT with similar affinity as myo-inositol and showed an IC50 value of 42 +/- 8 microM in L. donovani cultures. Finally, substrate affinities of MIT revealed apparent Km values of 84 +/- 8 microM for myo-inositol and 5.4 +/- 0.9 nM for H+, equal pH 8.27 + 0.08, suggesting that the L. donovani myo-inositol/H+ symporter is fully activated at physiological pH in the sandfly midgut or macrophage phagolysosome. We conclude that Leishmania MIT constitutes an attractive target for delivery of cytotoxic inositol analogues and differs significantly from the sodium-coupled myo-inositol transport system of the human host.  相似文献   
37.
38.
Pathogenic variants in the gene HGSNAT (heparan‐α‐glucosaminide N‐acetyltransferase) have been reported to underlie two distinct recessive conditions, depending on the specific genotype, mucopolysaccharidosis type IIIC (MPSIIIC)—a severe childhood‐onset lysosomal storage disorder, and adult‐onset nonsyndromic retinitis pigmentosa (RP). Here we describe the largest cohort to‐date of HGSNAT‐associated nonsyndromic RP patients, and describe their retinal phenotype, leukocyte enzymatic activity, and likely pathogenic genotypes. We identified biallelic HGSNAT variants in 17 individuals (15 families) as the likely cause of their RP. None showed any other symptoms of MPSIIIC. All had a mild but significant reduction of HGSNAT enzyme activity in leukocytes. The retinal condition was generally of late‐onset, showing progressive degeneration of a concentric area of paramacular retina, with preservation but reduced electroretinogram responses. Symptoms, electrophysiology, and imaging suggest the rod photoreceptor to be the cell initially compromised. HGSNAT enzymatic testing was useful in resolving diagnostic dilemmas in compatible patients. We identified seven novel sequence variants [p.(Arg239Cys); p.(Ser296Leu); p.(Phe428Cys); p.(Gly248Ala); p.(Gly418Arg), c.1543‐2A>C; c.1708delA], three of which were considered to be retina‐disease‐specific alleles. The most prevalent retina‐disease‐specific allele p.(Ala615Thr) was observed heterozygously or homozygously in 8 and 5 individuals respectively (7 and 4 families). Two siblings in one family, while identical for the HGSNAT locus, but discordant for retinal disease, suggest the influence of trans‐acting genetic or environmental modifying factors.  相似文献   
39.
A combined analysis procedure was used to study auditory, sensory evoked potentials (EPs) and event-related potentials (ERPs) in human subjects. Single sweep and averaged data were analysed in the time and frequency domains. Recognised peaks, seen in the averaged data, were related to specific poststimulus changes within conventional delta, theta and alpha frequency bands. The potential advantages of single sweep analysis, selective averaging and frequency domain analysis are discussed. The importance of studying prestimulus EEG activity in order to understand poststimulus changes is emphasised in relation to proposed hypotheses concerning brain dynamics and evoked response mechanisms. Specific frequency changes, elicited by target tones in auditory "odd ball" experiments, are described and contrasted to changes seen in EPs and nontarget ERPs. Our findings suggest that the P300 change of averaged data is the later consequence of poststimulus frequency changes which can be detected within the first 100 msec. The practical implications of our findings are briefly discussed.  相似文献   
40.
Hematological "masks" of malignant tumors of the internal organs are not infrequent in clinical practice. A total of 45 patients with malignant tumors of the internal organs (stomach-12, colon-9, liver-3, lungs-9, kidneys-6, pancreas-2, thyroid-2, bladder-1, prostate-1) were under observation. Hematological signs of bone marrow metastatic involvement were as follows: anemia (mainly hypochromic), leukemoid neutrophilic reaction, leukemoid reaction of myeloid type, erythrocytosis, thrombocytosis, plasmocyte bone marrow reaction. Early cancer diagnosis, especially in obscure peripheral blood changes, requires a complete all-round investigation of a patient including an analysis of clinico-anamnestic data, the use of radiographic and endoscopic methods, sternal puncture and trephine biopsy.  相似文献   
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