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11.
High-efficiency gene transfer to primary T lymphocytes by recombinant adenovirus vectors 总被引:3,自引:0,他引:3
Zhi Chen Matti Ahonen Heli Hmlinen Jeffrey M. Bergelson Veli-Matti Khri Riitta Lahesmaa 《Journal of immunological methods》2002,260(1-2):79-89
Recombinant, replication-deficient adenoviruses are efficient vectors for gene transfer to a wide range of cell types, with the exception of T lymphocytes. Here, we show that primary T lymphocytes from peripheral blood, cord blood, and the Jurkat T cell line are efficiently transduced by recombinant adenovirus. Nearly 100% infection efficiency of primary T cells is obtained with high multiplicity of infection (MOI) (5000) of recombinant adenovirus coding for lacZ. Similar infection efficiency by adenovirus-mediated gene transfer was obtained at lower MOI (3000) by activating primary T cells with PHA and PMA. Addition of cationic liposomes together with RAdlacZ markedly enhanced the infection efficiency at lower MOI (1000) resulting in over 90% infection efficiency. Primary T cells express low levels of coxsackievirus and adenovirus receptor (CAR), a cell surface receptor for adenovirus fiber attachment, as well as vβ3 and vβ5 integrins, cellular receptors for adenovirus internalization. This suggests that adenovirus entry to T cells at high MOI is mediated by other mechanisms. In conclusion, these results demonstrate that genes can be efficiently transferred to primary lymphocytes by adenovirus vectors at high MOI or in combination with cationic liposomes. 相似文献
12.
Korppi M 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2002,110(7-8):515-522
Seven paediatric studies on community-acquired pneumonia with serological methods for both viruses and bacteria have been published, allowing the evaluation of concomitant multiple etiological findings. In these studies, dual viral infection has been present in 0-14%, dual bacterial infection likewise in 0-14%, and mixed viral-bacterial infection in 3-30% of the pneumonia cases. The results confirm former clinical observations that respiratory viruses often pave the way for airway-colonising bacteria. The measured frequency of multiple infections has been dependent on the available test panel, mainly on the tests used for pneumococcal aetiology. Mixed viral-bacterial infections have been especially common in young children under 2 years of age, reflecting the high frequency of respiratory syncytial virus infections and their tendency to induce bacterial co-infections. No microbe-specific viral-bacterial associations have been demonstrated. The clinical implications of mixed viral-bacterial infections, compared with viral infections alone or bacterial infections alone, have so far remained unresolved. Current guidelines recommend antibiotic therapy for all community-acquired pneumonia cases in children. 相似文献
13.
Pekka Oja Raija M. T. Laukkanen T. Katriina Kukkonen-Harjula Ilkka M. Vuori Matti E. Pasanen Seppo P. T. Niittymäki Tiina Solakivi 《European journal of applied physiology》1991,62(6):400-404
Summary Two experiments were carried out to compare the cardiorespiratory and metabolic effects of cross-country skiing and running training during two successive winters. Forty-year-old men were randomly assigned into skiing (n = 15 in study 1,n = 16 in study 2), running (n = 16 in study 1 andn = 16 in study 2) and control (n = 17 in study 1 andn = 16 in study 2) groups. Three subjects dropped out of the programme. The training lasted 9–10 weeks with 40-min exercise sessions three times each week. The training intensity was controlled at 75%–85% of the maximal oxygen consumption (VO2max) using portable heart rate metres and the mean heart rate was 156–157 beats·min–1 in the training groups. In the pooled data of the two studies the mean increase in theVO2max (in ml·min–1·kg–1) on a cycle ergometer was 17% for the skiing group, 13% for the running group and 2% for the control group. The increase inVO2max was highly significant in the combined exercise group compared to the control group but did not differ significantly between the skiing and running groups. The fasting serum concentrations of lipoproteins and insulin did not change significantly in any of the groups. These results suggested that training by cross-country skiing and running of the same duration and intensity at each session for 9–10 weeks improved equally the cardiorespiratory fitness of untrained middle-aged men. 相似文献
14.
Tuure-Pekka Jauhiainen 《Macromolecular chemistry and physics.》1982,183(4):915-923
2,6-Dimethoxyphenol was polymerized using Ag2O-triethylamine complex as catalyst and a study made of the effect of the catalyst-monomer ratio on the yield, molar mass and polydispersity of poly(oxy-2,6-dimethoxy-1,4-phenylene). The glass transition temperatures Tg were measured with a computerized differential scanning calorimeter. The effect of the molar mass on Tg of poly(oxy-2,6-dimethoxy-1,4-phenylene) is discussed. The equation, Tg = Tg, ∞ ? K/M, describes well the dependence of Tg on the viscosity-average molar mass Mv from 1900 to 176000 g/mol. Some poly(oxy-2,6-dimethyl-1,4-phenylene) samples were studied as reference material. 相似文献
15.
High-density lipoproteins can act as carriers of glycophosphoinositol lipid-anchored CD59 in human plasma. 总被引:5,自引:0,他引:5
CD59 (protectin) is a glycophosphoinositol (GPI) lipid-anchored inhibitor of complement lysis that is expressed on the membranes of blood cells, endothelial cells, epithelial cells and cardiomyocytes. CD59 may be shed from cell surfaces, e.g. during cell injury, but when entering human plasma its fate is unknown. In this study we observed that radiolabelled lipid-anchored CD59, but not soluble urinary CD59 without anchor lipid, incorporated into high-density lipoprotein (HDL) particles when mixed with human serum and analysed by high resolution gel filtration and anti-apoA-I affinity chromatography. Only a small proportion of CD59 entered the low-density lipoprotein (LDL) fraction. HDL particles were capable of incorporating 25-42% of [125I]CD that was preinserted into the membranes of rabbit erythrocytes (RaE) and transferred 7-14% of [125I]CD59 back to RaE or to cultured human endothelial cells (EA.hy 926). Immunoaffinity purification and immunoblotting analysis demonstrated that HDL isolated from normolipidemic human serum contained small amounts of CD59. These results suggest that HDL particles could be involved in the recycling of GPI lipid-anchored molecules released from cell surfaces. 相似文献
16.
Comparison of class and subclass distribution of antibodies to the hepatitis B core and B e antigens in chronic hepatitis B 总被引:1,自引:0,他引:1
The IgG subclasses IgM and IgA1 of antibodies to hepatitis B core antigen (anti-HBc) and hepatitis B e antigen (anti-HBe) were assayed in sera from 82 patients with chronic hepatitis B utilising class/subclass-specific enzyme immunoassays (EIA). The solid-phase was either recombinant hepatitis B core antigen (rHBcAg) or rHBcAg converted to HBeAg by addition of 0.1% SDS with remaining HBcAg antigenicity blocked with monoclonal anti-HBc. Anti-HBc IgG1 was detected in 81 sera at a geometrical mean titre (GMT) of 296,110 x divided by 2.9. Anti-HBc IgG2 was not detected in any of the sera, and anti-HBc IgG3 and IgG4 were detected in 50 and 37 sera, respectively. Anti-HBc IgM and IgA1 were both significantly correlated to the presence of HBV DNA. The predominant antibody to HBeAg was found to be IgG1, being detected in 45 sera with a GMT of 1,035 x divided by 3.3. Anti-HBe IgG2 was not detected in any serum, while anti-HBe IgG3 and IgG4 were found in 8 and 23 sera, respectively. Anti-HBe IgG1, IgG3, and IgG4 were mainly detected in sera positive for anti-HBe in RIA (Abbott). No patient was found positive for anti-HBe IgA1 or IgM. Thus, in contrast to HBcAg, HBeAg does not trigger a persistent IgM and IgA1 response in chronic hepatitis B. The levels of anti-HBe IgG1 and IgG3 were much lower than the levels of anti-HBc IgG1 and IgG3. The presence of anti-HBe IgG4 was significantly correlated to that of anti-HBc IgG4.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
17.
18.
Immunohistochemical Study of Colorectal Tumors for Expression of a Novel Transmembrane Carbonic Anhydrase, MN/CA IX, with Potential Value as a Marker of Cell Proliferation 总被引:6,自引:4,他引:6
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Juha Saarnio Seppo Parkkila Anna-Kaisa Parkkila Kari Haukipuro Silvia Pastorekov Jaromir Pastorek Matti I. Kairaluoma Tuomo J. Karttunen 《The American journal of pathology》1998,153(1):279-285
Carbonic anhydrase isoenzyme IX, MN/CA IX, is a recently discovered member of the carbonic anhydrase (CA) gene family with a suggested function in acid-base balance, intercellular communication, and cell proliferation. Increased expression of MN/CA IX has been observed with certain epithelial tumors. We investigated the expression of MN/CA IX in 69 colorectal neoplasms, consisting of 1 juvenile polyp, 8 hyperplastic polyps, 39 adenomatous lesions, 21 carcinomas, and 7 metastases. Tissue sections were immunostained with a monoclonal antibody specific to MN/CA IX. The proliferative activity of the tumor cells was evaluated by Ki-67 antigen immunoreactivity. The hyperplastic polyps showed a weak or moderate reaction for MN/CA IX only in the cryptal epithelium, as did the normal intestinal mucosa. The adenomas showed immunoreactivity mainly in the superficial part of the mucosa, whereas the distribution in the carcinomas and metastases was more diffuse. Comparative immunostaining of serial sections for Ki-67, a well established marker of cell proliferation, confirmed that MN/CA IX is expressed in areas with high proliferative capacity. Our results show abnormal MN/CA IX expression in colorectal neoplasms, suggesting its involvement in their pathogenesis. The co-occurrence of MN/CA IX and Ki-67 in the same tumor cells indicates its potential for use as a marker of increased proliferation in the colorectal mucosa. 相似文献
19.
Huang XH Loimaala A Nenonen A Mercuri M Vuori I Pasanen M Oja P Bond G Koivula T Hiltunen TP Nikkari T Lehtimäki T 《Journal of molecular medicine (Berlin, Germany)》1999,77(12):853-858
The insertion/deletion (I/D) polymorphism of the human angiotensin-converting enzyme (ACE) gene is a major determinant of circulating ACE levels. The D allele has been suggested to be a potent risk factor for coronary artery disease; however, the effect of the ACE gene on carotid atherosclerosis remains controversial. We therefore studied the relationship between the ACE gene I/D polymorphism and carotid artery intima-media thickness (IMT). A random sample of 300 men aged 50-59 years living in southern Finland were selected, and 233 agreed to participate (74%). Data were collected in 219 subjects. Quantitative B-mode ultrasonography was used to measure the maximum near and far wall IMT of right and left common, bifurcation, and internal carotid artery. The mean maximum IMT (overall mean) was calculated as the mean of 12 maximum IMTs at 12 standard sites. Patients with an IMT higher than 1.7 mm in at least one of 12 standard sites were assumed to have carotid atherosclerosis. The I/D polymorphism was determined by polymerase chain reaction. Overestimation of the frequency of the DD genotype was eliminated by insertion-specific primer and the inclusion of 5% dimethylsulfoxide. No significant differences were found in carotid wall thickness between the three genotypes; the overall mean IMT were 1.18 +/- 0.30, 1.22 +/- 0.24, and 1.08 +/- 0.40 mm in genotypes of II, ID, and DD, respectively. Similarly, the ACE genotypes and allele frequencies did not differ significantly between the subjects with and those without carotid atherosclerosis. There was no association in the subgroups among only nonsmoking subjects or subjects without chronic medication. The present data indicate that the I/D polymorphism of the ACE gene is not related to carotid IMT and is unlikely to play a major role in carotid atherosclerosis. 相似文献
20.
Neuropathological Diagnostic Criteria for Creutzfeldt-Jakob Disease (CJD) and Other Human Spongiform Encephalopathies (Prion Diseases) 总被引:12,自引:0,他引:12
Herbert Budka Adriano Aguzzi Paul Brown Jean-Marie Brucher Orso Bugiani Filippo Gullotta Matti Haltia Jean-Jacques Hauw James W. Ironside Kurt Jellinger Hans A. Kretzschmar Peter L. Lantos Carlo Masullo Wolfgang Schlote Jun Tateishi Roy O. Weller 《Brain pathology (Zurich, Switzerland)》1995,5(4):459-466
Neuropathological diagnostic criteria for Creutzfeldt-Jakob disease (CJD) and other human transmissible spongiform encephalopathies (prion diseases) are proposed for the following disease entities: CJD - sporadic, iatrogenic (recognised risk) or familial (same disease in 1st degree relative): spongiform encephalopathy in cerebral and/or cerebellar cortex and/or subcortical grey matter; or encephalopathy with prion protein (PrP) immuno-reactivity (plaque and/or diffuse synaptic and/or patchy/perivacuolar types). Gerstmann-Sträussler-Scheinker disease (GSS) (in family with dominantly inherited progressive ataxia and/or dementia): encephalo(myelo)pathy with multicentric PrP plaques. Familial fatal insomnia (FFI) (in member of a family with PRNP178 mutation): thalamic degeneration, variable spongiform change in cerebrum. Kuru (in the Fore population). Without PrP data, the crucial feature is the spongiform change accompanied by neuronal loss and gliosis. This spongiform change is characterised by diffuse or focally clustered small round or oval vacuoles in the neuropil of the deep cortical layers, cerebellar cortex or subcortical grey matter, which might become confluent. Spongiform change should not be confused with non-specific spon-giosis. This includes status spongiosus (“spongiform state”), comprising irregular cavities in gliotic neuropil following extensive neuronal loss (including also lesions of “burnt-out” CJD), “spongy” changes in brain oedema and metabolic encephalopathies, and artefacts such as superficial cortical, perineuronal, or perivascular vacuolation; focal changes indistinguishable from spongiform change may occur in some cases of Alzheimer's and diffuse Lewy body diseases. Very rare cases might not be diagnosed by these criteria. Then confirmation must be sought by additional techniques such as PrP immunoblotting, preparations for electron microscopic examination of scrapie associated fibrils (SAF), molecular biologic studies, or experimental transmission. 相似文献