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941.
OBJECTIVES: To generate a recombinant fusion protein (FP) based on the endotoxin-binding domain of bactericidal/permeability-increasing protein (BPI) and the constant domain of IgG and to test its ability to inhibit lipopolysaccharide (LPS)-induced macrophage tumor necrosis factor alpha (TNF-alpha) secretion. DESIGN: A murine macrophage cell line, RAW 264.7, was transfected with a BPI-IgG FP before incubation with LPS. The amount of LPS-induced TNF-alpha protein secreted was measured and compared with that secreted by cells transfected with a control construct. SETTING: Basic science research laboratory. MAIN OUTCOME MEASURES: Secreted TNF-alpha protein concentration. RESULTS: After transfection, RAW 264.7-cell FP expression was detected in cell lysates and supernatants. At each LPS dose tested, cells transfected with the FP gene secreted less TNF-alpha than did cells transfected with a control construct. CONCLUSIONS: The FP possesses substantial antiendotoxin activity, as delineated by inhibition of LPS-induced TNF-alpha secretion by murine macrophages transfected with the fusion gene construct. In the future, such FP may be used as a clinical reagent to reduce the morbidity and mortality associated with serious gram-negative bacterial infections in surgical patients.  相似文献   
942.
943.
Purpurogallin (PPG) in an active cytoprotector found in certain oak barks. We have shown that PPG prolongs the survival of cultured cardiocytes from rats and rabbits against different oxidants better than do antioxidants such as Trolox (a hydrophilic analogue of vitamin E) in a morphometric assay system. First, we verified by X-ray crystallography that PPG is a bicyclic molecule comprising a phenolic ring fused with a seven-membered ring in a highly planar conformation. In analogues of PPG wherein the two double bonds in the seven membered ring of the parent molecule are saturated or where the four OH groups of the parent compound are substituted by four OCH3 groups, the derivatives are less planar and less protective of the human cells than native PPG. Second, PPG in a concentration-dependent manner protected myocytes and endothelial cells of humans against oxyradicals generated with any one of the following oxyradical generators: (a) xanthine oxidase plus hypoxanthine, (b) menadione, or (c) paraquat. In each case, PPG was more cytoprotective than comparative antioxidants. Also, PPG protected erythrocytes against peroxyl radicals better than the two PPG derivatives mentioned. Third, the cytoprotective action of PPG detected in vitro was accompanied by declines of malondialdehyde. Finally, we observed that PPG chelated ferrous ions and, therefore, can suppress the formation of radicals in the Fenton reaction. Thus, PPG with its molecular architecture and presumably its affinity for ferrous ions protects multiple types of cardiovascular cells against oxyradicals.  相似文献   
944.
BACKGROUND/AIMS: Since 1989, thirty-two patients with advanced, intra-abdominal pancreatic cancer were treated with regional chemotherapy in combination with extracorporeal hemofiltration. PATIENTS and METHODS: Eleven patients had locally advanced, unresectable cancer, and ten had advanced disease with liver metastases. Three patients had developed liver metastases following a radical resection. One patient had an incomplete resection with local residual disease, and a second had developed a local recurrence after a radical resection. One patient had an unresectable cystadenocarcinoma. Five patients had failed prior systemic therapies for unresectable pancreatic cancer. The patients underwent 85 treatments with regional chemotherapy plus hemofiltration, an average of 2.7 treatments per patient. RESULTS: Of 21 patients treated primarily with regional chemotherapy plus hemofiltration, there were two complete responses (9%) and eight partial responses (38%), an overall total response rate of 47%. The average survival for patients with Stage II/III localized, unresectable disease is 13 months and that for Stage IV unresectable disease with liver metastases is 9 months. CONCLUSIONS: Patients with recurrent disease following a radical resection or having failed prior systemic therapies generally had no benefit from regional chemotherapy plus hemofiltration.  相似文献   
945.
Avoidable deaths from asthma continue, even in hospital. Since the management of acute severe asthma is often initiated in the Accident and Emergency department, it is crucial that staff there have adequate knowledge. An anonymous questionnaire, containing items based on chart 6 of the UK guidelines, was completed by 66 Accident and Emergency Senior House Officers from the Yorkshire region. The study aim was to establish these doctors' levels of knowledge about the recommended management of acute asthma in Accident and Emergency. The median score was 10 (out of a possible 24) and the interquartile range 8-13. Further efforts are required to implement these guidelines so that the best patient outcomes can be achieved.  相似文献   
946.
An intervention, with forgiveness toward their abuser as the goal, was implemented with 12 female incest survivors. The women, from a midwestern city, were 24 to 54 years old, and all were Caucasian. A yoked, randomized experimental and control group design was used. The participants were randomly assigned to an experimental group (receiving the forgiveness intervention immediately) or a waiting-list control group (receiving the intervention when their matched experimental counterpart finished the intervention). Each participant met individually with the intervener once per week. The average length of the intervention for the 12 participants was 14.3 months. A process model of forgiveness was used as the focus of intervention. Dependent variables included forgiveness, self-esteem, hope, psychological depression, and state-trait anxiety scales. After the intervention, the experimental group gained more than the control group in forgiveness and hope and decreased significantly more than the control group in anxiety and depression. When the control group then began the program they showed similar change patterns to the above, as well as in self-esteem improvement.  相似文献   
947.
As researchers investigate methods of automated interpretation of the electroencephalogram (EEG), spectral topography is emerging as an important and popular technique in applied clinical neurophysiology. Several computer-based EEG topography systems have been developed to produce topographic maps showing the spatial distributions of pre-defined frequency bands in the EEG. However, there is ongoing debate as to which technical approaches to EEG topography generate maps that can be most accurately interpreted by clinicians. This paper reviews existing topographic techniques, particularly as they apply to diagnostic neurology, and discusses some of the technical choices that must be addressed by topography users. These choices include the selection of montage, epoch length, interpolation scheme, graphical display method, and artifact removal technique. The points summarised here highlight the general opinion that although EEG topography has many benefits, it should be invoked with care and the user should possess an indepth understanding of the procedures used to produce the topographic maps.  相似文献   
948.
Mucosal antibody induction by otherwise identical replication-competent and replication-incompetent rhesus monkey rotaviruses was compared. Although psoralen-inactivated virus induced diarrhea, the magnitude of the intestinal antibody response was severely attenuated compared with that of replicating rotavirus, as determined by assay of mucosal antibody-secreting cells. Rotavirus that was neutralized by monoclonal antibodies (anti-VP4 and -VP7) prior to inoculation was similarly ineffective at induction of specific antibodies in intestinal secretions. In contrast to genetically inactivated virus, antibody-neutralized virus did not induce diarrhea. In this murine model, viral replication is an important determinant of antibody induction. The diarrhea response is blocked by neutralizing antibodies, but the mechanism of action is not exclusively the inhibition of viral replication.  相似文献   
949.
The Serratia marcescens haemophore HasA is secreted by an ABC exporter comprising three envelope proteins. The ABC protein (ATP-binding cassette) HasD and the MFP protein (membrane fusion protein) HasE but not the outer membrane component have been isolated previously. In Escherichia coli, TolC, the outer membrane component of the haemolysin transporter, can form a hybrid exporter with HasD and HasE. This hybrid secretes HasA and the very similar metalloproteases from S. marcescens and Erwinia chrysanthemi. By analogy, the genuine exporter was predicted to secrete metalloproteases. The hasF gene was thus cloned from S. marcescens into an E. coli tolC mutant carrying hasD and hasE genes, by screening for a proteolytic phenotype on skimmed-milk plates. hasF encodes a protein sharing 74% identity with the E. coli TolC protein. Anti-TolC antibodies cross-reacted with a protein with an apparent molecular weight of 53 kDa in E. coli expressing hasF and in S. marcescens. hasF is unlinked to the has cluster and, unlike the has operon, is not iron regulated. hasF complements some of the tolC phenotypes, including drug- and detergent sensitivities and haemolysin secretion but not colicin E1 uptake. This suggests that the various functions of TolC could correspond to distinct domains on the protein.  相似文献   
950.
P-selectin glycoprotein ligand-1 (PSGL-1) is a disulfide-bonded homodimeric mucin-like glycoprotein on leukocytes that interacts with both P- and E-selectin. In this report we describe the structures of the Ser/Thr-linked O-glycans of PSGL-1 synthesized by HL-60 cells metabolically radiolabeled with 3H-sugar precursors. In control studies, the O-glycans on CD43 (leukosialin), a mucin-like glycoprotein also expressed by HL-60 cells, were analyzed and compared to those of PSGL-1. O-Glycans were released from Ser/Thr residues by mild base/borohydride treatment of purified glycoproteins, and glycan structures were determined by a combination of techniques. In contrast to expectations, PSGL-1 is not heavily fucosylated; a majority of the O-glycans are disialylated or neutral forms of the core-2 tetrasaccharide Galbeta1-->4GlcNAcbeta1-->6(Galbeta1-->3)GalNAcOH++ +. A minority of the O-glycans are alpha-1,3-fucosylated that occur as two major species containing the sialyl Lewis x antigen; one species is a disialylated, monofucosylated glycan, and the other is a monosialylated, trifucosylated glycan having a polylactosamine backbone. CD43 lacks the fucosylated glycans found on PSGL-1 and is enriched for the nonfucosylated, disialylated core-2 hexasaccharide. These results demonstrate that PSGL-1 contains unique fucosylated O-glycans that are predicted to be critical for high affinity interactions between PSGL-1 and selectins.  相似文献   
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