共查询到20条相似文献,搜索用时 15 毫秒
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Intravenous injection of Candida albicans into mice produced elevated serum tumor necrosis factor alpha (TNF-alpha) levels. We hypothesized that immunostimulants released in vivo from C. albicans during fungal sepsis might contribute to the elevated levels of TNF-alpha in serum. We tested this hypothesis in mice with C. albicans mannan (CAM). Increased serum TNF-alpha levels were observed following intravenous and intraperitoneal injections of CAM. Injection of CAM into mice resulted in increased serum TNF-alpha concentrations that reached 1,200 pg/ml of blood, compared with 2,400 microg/ml of blood following injection of 10 microg of endotoxin. The response to CAM was concentration dependent, requiring a minimum dose of 20 microg of CAM per g of body weight. Sera from mice were tested 30, 60, 90, and 120 min after intravenous injections with CAM. TNF-alpha concentrations were minimal 30 and 120 min after intravenous injection and maximal 60 and 90 min after CAM injection. The relative distribution of CAM in vivo in decreasing order was determined to be as follows: blood > liver > lung > spleen, 90 min following injection of a single 5-mg dose of CAM. CAM was confirmed as the stimulating substance by utilizing anti-CAM antibodies in vivo to block the response. Rabbit anti-mannan antibodies administered by intraperitoneal injection 24 h before CAM injection significantly suppressed (P < 0.05) the accumulation of TNF-alpha in the sera. Dexamethasone administered to mice before intravenous injection of mannan significantly reduced (40 to 90% reduction; P < 0.05) the concentrations of TNF-alpha in the sera of treated mice. Thus, when in vivo CAM clearance mechanisms are exceeded, sufficient CAM may become available to stimulate TNF-alpha production, making CAM an important part of pathogenesis in Candida sepsis. 相似文献
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BACKGROUND: Reducing inappropriate hospital admissions could lead to lower total health care costs without compromising the quality of care. Research suggests that a sizeable portion of hospital admissions are inappropriate. Other studies indicate that family physicians use health care resources, including hospitalizations, less often than other primary care physicians. To gain additional insight into family physicians' decisions to admit patients, we performed an exploratory study using the Appropriateness Evaluation Protocol, a validated, clinically based utilization review instrument. METHODS: We assessed admissions by community-based and residency-based family physicians to a single university-affiliated hospital during calendar year 1988. A total of 905 patients were admitted to the hospital by family physicians during the study period. Of these, 889 records had complete data. Each was reviewed for appropriateness of admission. We calculated percentages of inappropriate admissions and used logistic regression to ascertain variables that were significant predictors of inappropriateness. RESULTS: Overall, 5.4 percent of admissions were categorized as inappropriate. Omitting obstetric cases, the rate was 10.5 percent. Inappropriate admissions did not cluster around a small number of diagnoses or diagnosis-related groups. Using logistic regression, we found that urgency of admission, patient insurance status, and residency-based physician admission versus community-based physician admission were significant predictors of inappropriate hospital use. Of the inappropriate admissions, 70 percent were so rated because diagnostic procedures or treatments could have been performed on an outpatient basis. CONCLUSIONS: In contrast with other studies for which physician specialty was not controlled, family physicians less frequently admitted patients inappropriately. Predictors of inappropriateness differed from those found in other studies. Changes in hospital systems, in addition to educational efforts directed toward individual physicians, hold promise as a strategy for reducing inappropriate hospital use. 相似文献
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The Walker carcinosarcoma cells were cultured in the medium with low concentration (0.25%) of fetal calf serum, in the presence of native or methylamine-treated (modified) human alpha 2-macroglobulin (alpha 2-MG) in vitro. The proliferative activity (3H-thymidine incorporation) of these cells increased in the presence of one or the other alpha 2-MG preparation. It allows to suppose that the human alpha 2-MG may serve as a growth-stimulating factor of tumour cells. 相似文献
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Cell fate determination in the developing vertebrate retina is characterized by the sequential generation of seven classes of cells by multipotent progenitor cells. Despite this order of genesis, more than one cell type is generated at any time; for example, in the rat, several cell types are born during the prenatal period, while others are born postnatally. In order to examine whether there are classes of progenitor cells with distinct developmental properties contributing to this developmental progression, we examined antigen expression in progenitor cells during rat retinal development. Two markers of amacrine and horizontal cells, the VC1.1 epitope and syntaxin, were found to be expressed on a subset of progenitors in a temporally regulated manner that closely paralleled the birthdays of these cell types. In order to investigate which cell types were produced by the progenitors expressing these markers, fluorescent latex microspheres covalently coupled to VC1.1 antibodies were used to indelibly label VC1.1+ progenitor cells and their progeny. Early in retinal development, VC1.1+ progenitors generated a high percentage of amacrine and horizontal cells, but no cone photoreceptors. During this same period, a comparable number of cone photoreceptors were generated by VC1.1- progenitors. In the late embryonic and early postnatal period, VC1.1+ progenitors continued to generate predominantly amacrine cells, but also gave rise to an increasing number of rod photoreceptors. These findings demonstrate that expression of these two markers by progenitors is highly correlated with a bias towards the production of amacrine and horizontal cells. The fact that subsets of progenitors with temporally regulated and distinct biases are intermingled within the retinal neuroepithelium provides a basis for understanding how different cell types are generated both simultaneously and in a particular order by multipotent progenitors during retinal development. 相似文献
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W McGuire JC Knight AV Hill CE Allsopp BM Greenwood D Kwiatkowski 《Canadian Metallurgical Quarterly》1999,179(1):287-290
A rapid, sensitive, and simple method was developed to detect the sapstain fungi Ophiostoma piceae and O. quercus in stained wood. By using microwave heating for DNA extraction and PCR with internal transcribed spacer-derived-specific primers, detection was feasible within 4 h, even with DNA obtained from a single synnema. This method can easily be extended for the detection of other wood-inhabiting fungi. 相似文献
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M Sumitomo S Suda K Shindo M Fukumura J Fukushima K Okuda A Ito 《Canadian Metallurgical Quarterly》1997,46(11):1136-1147
In order to investigate the role of tumor necrosis factor alpha (TNF-alpha) in bronchial asthma or chronic respiratory infection, we measured serum levels of TNF-alpha and serum soluble tumor necrosis factor-receptor I (sTNF-RI) in asthmatic patients (n = 11) and patients (n = 10) with chronic respiratory infection by Pseudomonas aeruginosa. We also measured serum levels of eosinophil cationic protein (ECP) in the asthmatic patients. The serum levels of TNF-alpha in the asthmatic patients, patients with chronic respiratory tract infection and control group were 2.864 +/- 0.719 g/ml, 2.564-1.384 pg/ml and 0.681 +/- 0.453 pg/ml respectively. The levels of the former two groups were higher than those of the control group (p < 0.05). The serum levels of sTNF-RI in the asthmatic patients, the patients with chronic respiratory tract infection, and the control group was 758 +/- 268 pg/ml, 999 +/- 242 pg/ml and 909 +/- 268 pg/ml respectively. The levels of the former two groups did not differ significantly from those of the control group. There were significant correlations between TNF-alpha and sTNF-RI in the control group and in the patients with chronic respiratory tract infection, but there was no significant correlation in the asthmatic patients. In the asthmatic patients. TNF-alpha/s TNF-RI correlated with %best of PEF (r = 0.691, n = 9, p 0.0373). The serum levels of ECP correlated significantly with TNF-alpha, but not with sTNF-RI in the asthmatic patients. It is suggested that TNF-alpha plays a significant role in the pathogenesis of bronchial asthma and chronic respiratory tract infection as a factor causing inflammation and that the increase of TNF-alpha/sTNF-RI reflects the activation of eosinophil functions in an asthmatic attack. 相似文献
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EW Uhl LL Moldawer WW Busse TJ Jack WL Castleman 《Canadian Metallurgical Quarterly》1998,152(2):513-522
Increased airway resistance and airway hyperresponsiveness induced in rats by infection with parainfluenza type I (Sendai) virus is associated with bronchiolar fibrosis. To determine whether increased tumor necrosis factor (TNF)-alpha gene expression is an important regulatory event in virus-induced bronchiolar fibrosis, pulmonary TNF-alpha mRNA and protein expression was assessed in rat strains that are susceptible (Brown Norway; BN) and resistant (Fischer 344; F344) to virus-induced bronchiolar fibrosis. Virus-inoculated BN rats had increased TNF-alpha pulmonary mRNA levels (P < 0.05) and increased numbers of bronchiolar macrophages and fibroblasts expressing TNF-alpha protein compared with virus-inoculated F344 rats (P < 0.05). Virus inoculation also induced elevated TNF-alpha mRNA and protein levels (P < 0.05) in cultured rat alveolar macrophages (NR8383 cells). A 55-kd soluble TNF receptor-immunoglobulin G fusion protein (sTNFR-IgG) was used to inhibit TNF-alpha bioactivity in virus-inoculated BN rats. Treated rats had fewer proliferating bronchiolar fibroblasts, as detected by bromodeoxyuridine incorporation, compared with virus-inoculated control rats (P < 0.05). There was also increased mortality in p55sTNFR-IgG-treated virus-inoculated rats associated with increased viral replication and decreased numbers of macrophages and lymphocytes in bronchoalveolar lavage fluid (P < 0.05). The results of this study indicate that 1) Sendai virus can directly up-regulate TNF-alpha mRNA and protein expression in macrophages, 2) TNF-alpha is an important mediator of virus-induced bronchiolar fibrosis, and 3) TNF-alpha has a critical role in the termination of Sendai viral replication in the lung. 相似文献
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K Benihoud I Saggio P Opolon B Salone F Amiot E Connault C Chianale F Dautry P Yeh M Perricaudet 《Canadian Metallurgical Quarterly》1998,72(12):9514-9525
The efficiency of adenovirus-mediated gene transfer is now well established. However, the cellular and the humoral immune responses triggered by vector injection lead to the rapid elimination of the transduced cells and preclude any efficient readministration. The present investigation focuses on the role of tumor necrosis factor alpha (TNF-alpha), a proinflammatory cytokine, and the related cytokine lymphotoxin alpha (LTalpha), in mounting an immune reaction against recombinant adenovirus vectors. After gene transfer in the liver, mice genetically deficient for both cytokines (TNF-alpha/LTalpha-/-), in comparison with normal mice, presented a weak acute-phase inflammatory reaction, a reduction in cellular infiltrates in the liver, and a severely impaired T-cell proliferative response to both Adenoviral and transgene product antigens. Moreover, we observed a strong reduction in the humoral response to the vector and the transgene product, with a drastic reduction of anti-adenovirus immunoglobulin A and G antibody isotypes. In addition, the reduction in antibody response observed in TNF-alpha/LTalpha-/- and TNF-alpha/LTalpha+/- mice versus TNF-alpha/LTalpha+/+ mice links antibody levels to TNF-alpha/LTalpha gene dosage. Due to the absence of neutralizing antibodies, the TNF-alpha/LTalpha knockout mice successfully express a second gene transduced by a second vector injection. The discovery of the pivotal role played by TNF-alpha in controlling the antibody response against adenovirus will allow more efficient adenovirus-based strategies for gene therapy to be proposed. 相似文献
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A case of partial bone necrosis of the articular tubercle of the temporomandibular joint is presented. It was probably caused by repeated injections of sodium hyaluronate in the joint. A sequestrectomy was performed under general anesthesia, and the postoperative course was uneventful. 相似文献
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P Hjelmstr?m CS Peacock R Giscombe R Pirskanen AK Lefvert JM Blackwell CB Sanjeevi 《Canadian Metallurgical Quarterly》1998,88(1-2):137-143
The production of verotoxin was examined in 2152 Escherichia coli isolates from 387 cattle in Japan from 1992 to 1994. The toxin was detected in 263 isolates from 94 cattle (detection rate: 24.3%). Verotoxin-producing E. coli (VTEC) was isolated from the cattle in 15 out of 17 prefectures, and the strains were divided into 33 serotypes. E. coli O157:H7 was isolated from 7 out of 387 cattle (detection rate: 1.8%) in four prefectures. These results suggest that VTEC is widely distributed in Japan and include a wide variety of serotypes. 相似文献
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B Foxwell K Browne J Bondeson C Clarke R de Martin F Brennan M Feldmann 《Canadian Metallurgical Quarterly》1998,95(14):8211-8215
Tumor necrosis factor (TNF) alpha has been shown to be a major therapeutic target in rheumatoid arthritis with the success of anti-TNFalpha antibody clinical trials. Although signaling pathways leading to TNFalpha expression have been studied in some detail, there is evidence for considerable differences between individual cell types. This prompted us to investigate the intracellular signaling pathways that result in increased TNFalpha synthesis from macrophages in the diseased synovial joint tissue. Using an adenoviral system in vitro we report the successful delivery of genes to more than 95% of normal human macrophages. This permitted us to show, by using adenoviral transfer of IkappaB alpha, the natural inhibitor of NF-kappaB, that induction of TNFalpha in normal human macrophages by lipopolysaccharide, but not by some other stimuli, was inhibited by 80%. Furthermore the spontaneous production of TNFalpha from human rheumatoid joint cell cultures was inhibited by 75%, indicating that the NF-kappaB pathway is an essential step for TNFalpha synthesis in synovial macrophages and demonstrating that NF-kappaB should be an effective therapeutic target in this disease. 相似文献
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L Usnarska-Zubkiewicz 《Canadian Metallurgical Quarterly》1998,99(1):30-37
The effect of original analogues of the 6-9 C-terminal AVP fragment, D-MRP and D-MPRG, on the active avoidance behaviour of rats was studied using intranasal administration in a wide range of doses. The dose in 0.1 mcg/kg was the most efficient for D-MPR and 0.01 mcg/kg for D-MPRG, which for the tripeptide was ten times, and for the tetrapeptide hundred times lower than the corresponding dose of AVP used in the similar experiments. The tri- and tetrapeptide were shown to facilitate the active avoidance behaviour affecting both the formation of the reaction and consolidation of memory trace. The peptides mostly affect the perception processes, i.e., the detection of a specific stimulus from the environment, the estimation and memorizing of its biological significance. 相似文献
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M Kondrusik T Hermanowska-Szpakowicz E Jaroszewicz 《Canadian Metallurgical Quarterly》1998,4(21):126-129
CSF concentrations of TNF-alpha and Il-1 beta were detected in patients with TBE. The cytokines were detected by immunometric assay by MEDGENIX kit. CSF Concentrations of TNF-alpha and IL-1 beta in patients with TBE were significantly higher than in control group before as well as after treatment and normalization of CSF parameters. These concentrations were lower comparing to one obtained in group of bacterial meningitis. There was no correlation between concentration of cytokines and other CSF parameters (cytosis, protein, glucose concentration). Concentrations of analysed cytokines did not change significantly before and after treatment. Detection of CSF concentrations of TNF-alpha and Il-1 beta in patients with tick-borne encephalitis can be used to evaluate efficacy of treatment and retreat of infection. 相似文献
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A Chcia?owski T P?usa C Szczylik B Mame?ka I Bajera T Targowski S Dudko G Wcis?o 《Canadian Metallurgical Quarterly》1997,2(12):382-384
Tumor Necrosis Factor alfa (TNFa) is a cytokine with cytolytic and cytotoxic properties. First clinical trials in which TNF was administered parenterally date back to early 70-ties. Soon it was noticed that when administered strictly to the tumor mass TNF exhibits high anti-tumor efficacy, exemplified by total or at least substantial regression of the tumor mass while producing minor and controllable symptoms. In this paper the case of local administration of the recombinant TNFa directly into the tumor mass constricting the bronchus was presented. 相似文献
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MG Netea N de Bont PN Demacker BJ Kullberg LE Jacobs TJ Verver-Jansen AF Stalenhoef JW Van der Meer 《Canadian Metallurgical Quarterly》1998,66(5):2365-2367
Lipoproteins can bind lipopolysaccharide (LPS) and decrease LPS-stimulated cytokine production. Lipoprotein(a) [Lp(a)] was as potent as low-density lipoproteins (LDL) in inhibiting LPS-stimulated tumor necrosis factor synthesis by human mononuclear cells. The kinetics of LPS inhibition by Lp(a) was similar to that of LDL. This suggests that circulating Lp(a) may be an important factor determining the amplitude of the response to LPS in humans. 相似文献
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Y Nakajima O Mikami M Yoshioka Y Motoi T Ito Y Ishikawa M Fuse K Nakano K Yasukawa 《Canadian Metallurgical Quarterly》1997,62(3):297-298
The presence of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) activities was determined in milk and serum of cows with naturally occurring coliform mastitis (CFM). TNF-alpha was detected in the sera from 26 of 32 cows with CFM. TNF-alpha levels were higher in the sera than in the milk. IL-6 was high in the sera of surviving CFM animals, but was low in animals that died and in healthy controls. Furthermore, the mean level of IL-6 was 20-fold higher in the milk than in the sera of mastitic cows. The level of IL-6 in the serum was correlated to that in the milk in individual animals. The presence of IL-6 and TNF-alpha in the sera appears to relate to severe clinical condition of CFM, in the milk whereas they may play a role in generating inflammation of the mammary gland. 相似文献