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171.
HM Abdel-Dayem SY Naddaf WS Omar M Aziz J Gillooley 《Canadian Metallurgical Quarterly》1997,38(8):1213-1215
We report an unusual finding in an AIDS patient who presented with a large mediastinal mass and multiple lymphadenopathy. A sequential thallium and gallium scan to specify the nature of the mediastinal mass was requested. The early thallium images, acquired 15 min after the intravenous injection, showed no uptake in the mass. The delayed images 2 hr later showed intense thallium uptake. A gallium scan performed 48 hr later also showed intense gallium uptake in the mediastinal mass. Biopsy from the inguinal lymph node confirmed the presence of large-cell diffuse noncleaved malignant lymphoma. This case raises questions about the optimum time of imaging for thallium in high-grade lymphoma, whether delayed imaging is essential, about previous reports of low sensitivity of thallium in undifferentiated lymphoma and about the mechanism of thallium uptake in this type of tumor. 相似文献
172.
M Taira I Komiya T Taira T Arakawa S Hokama Y Nagasawa N Takasu 《Canadian Metallurgical Quarterly》1998,15(12):1065-1067
Diabetic muscle infarction (DMI) is a rare complication of diabetes mellitus. We report the first recorded case in Japan. A 45-year-old Japanese woman presented with severe pain in the left antero-medial thigh. She had a 14-year history of Type 2 diabetes mellitus (DM). She had first noticed pain in her left thigh after a walk 2 weeks prior to presentation. The pain worsened progressively. She noticed a firm mass in her left thigh. T2-weighted magnetic resonance imaging (MRI) demonstrated a high-intensity signal in the muscle bulk of the anterior component of the left thigh. A needle biopsy of the mass showed necrosis. She was treated with bedrest and an antiplatelet agent. The mass disappeared 8 weeks after admission. DMI is a rare complication of poorly controlled diabetes mellitus. Twenty-seven cases with DMI have been reported in the English literature but we believe this is the first Japanese case with DMI. 相似文献
173.
Using the yeast two-hybrid protein-protein interaction system to search for genes capable of forming dimers with the antiapoptotic protein Mcl-1, we have isolated BOD (Bcl-2-related ovarian death agonist) from an ovarian fusion cDNA library. The three variants of BOD (long, medium, and short) have an open reading frame of 196, 110, and 93 amino acids, respectively; all of them contain a consensus Bcl-2 homology 3 (BH3) domain but lack other BH domains found in channel-forming Bcl-2 family proteins. In the yeast cell assay, BOD interacts with diverse antiapoptotic Bcl-2 proteins [Mcl-1, Bcl-2, Bcl-xL, Bcl-w, Bfl-1, and Epstein-Barr virus (EBV) BHRF-1] but not with different proapoptotic Bcl-2 proteins (BAD, Bak, Bok, and Bax). After overexpression in mammalian Chinese hamster ovary (CHO) cells, BOD induces apoptosis that can be prevented by the baculoviral caspase inhibitor P35. The cell-killing activity of BOD is also antagonized in cells cotransfected with the antiapoptotic Bcl-w protein, which showed high affinity for BOD in the two-hybrid assay. Furthermore, mutagenesis studies showed that BOD mutants with alterations in the BH3 domain lose cell-killing ability, suggesting that the BH3 domain is important for the mediation of cell killing by BOD. BOD mRNA is ubiquitously expressed in ovary and multiple other tissues. The BOD gene is also conserved in diverse mammalian species. Identification of BOD expands the group of proapoptotic Bcl-2 proteins that only contains the BH3 domain and allows future elucidation of the intracellular mechanism for apoptosis regulation in ovary and other tissues. 相似文献
174.
The scabrous (sca) gene encodes a secreted dimeric glycoprotein with putative coiled-coil domains N-terminally and a C-terminal region related to the blood clot protein fibrinogen. Homozygous sca mutants have extra bristle organs and rough eyes. We describe a GAL4-based expression system for testing rescue of the sca mutant phenotype by altered SCA proteins and for misexpression. We find that deletion of the fibrinogen-related domain (FReD) greatly decreases SCA function, confirming the importance of this conserved region. SCA function could not be restored by FReDs from human fibrinogen chain genes. However, proteins lacking any FReD still showed some function in both rescue and misexpression experiments, suggesting that putative effector-binding regions lie outside this domain. Consistent with this, proteins expressing only the FReD had no rescuing activity but were recessive negative; i.e., they enhanced the phenotype of sca mutations but had no phenotype in the presence of a wild-type sca allele. This suggests that the FReD contributes to SCA function by binding to other components of the bristle determination pathway, increasing the activity of the linked N-terminal region. 相似文献
175.
Human N-acetylmuramyl-L-alanine amidase (EC 3.5.1.28) degrades peptidoglycan, a major component of bacterial cell walls with potent pro-inflammatory cytokine-inducing properties. We postulate that degradation of peptidoglycan by N-acetylmuramyl-L-alanine amidase is important for the inactivation of inflammatory peptidoglycan products in human tissues. The inflammatory activities of peptidoglycan digested by lysozyme and/or amidase were investigated using two properties of peptidoglycan: its capacity to induce the release of the inflammatory cytokines IL-1, IL-6 and TNF-alpha in vivo and in vitro and its capacity to induce arthritis in Lewis rats. The results show that after subsequent treatment with both lysozyme and amidase, the peptidoglycan products were unable to induce arthritis in Lewis rats. The production of pro-inflammatory cytokines in mice after intravenous injection of cell wall fragments was lower after in vitro degradation of the cell wall fragments by amidase. These in vivo results were confirmed with whole blood assays in which the production of pro-inflammatory cytokines was measured after stimulation with lysozyme- and amidase-treated peptidoglycan. The results show that human N-acetylmuramyl-L-alanine amidase possesses an enzymatic activity capable of inactivating inflammatory peptidoglycan by lowering its cytokine-inducing properties. 相似文献
176.
AO Charkowski JR Alfano G Preston J Yuan SY He A Collmer 《Canadian Metallurgical Quarterly》1998,180(19):5211-5217
The host-specific plant pathogen Pseudomonas syringae elicits the hypersensitive response (HR) in nonhost plants and secretes the HrpZ harpin in culture via the Hrp (type III) secretion system. Previous genetic evidence suggested the existence of another harpin gene in the P. syringae genome. hrpW was found in a region adjacent to the hrp cluster in P. syringae pv. tomato DC3000. hrpW encodes a 42. 9-kDa protein with domains resembling harpins and pectate lyases (Pels), respectively. HrpW has key properties of harpins. It is heat stable and glycine rich, lacks cysteine, is secreted by the Hrp system, and is able to elicit the HR when infiltrated into tobacco leaf tissue. The harpin domain (amino acids 1 to 186) has six glycine-rich repeats of a repeated sequence found in HrpZ, and a purified HrpW harpin domain fragment possessed HR elicitor activity. In contrast, the HrpW Pel domain (amino acids 187 to 425) is similar to Pels from Nectria haematococca, Erwinia carotovora, Erwinia chrysanthemi, and Bacillus subtilis, and a purified Pel domain fragment did not elicit the HR. Neither this fragment nor the full-length HrpW showed Pel activity in A230 assays under a variety of reaction conditions, but the Pel fragment bound to calcium pectate, a major constituent of the plant cell wall. The DNA sequence of the P. syringae pv. syringae B728a hrpW was also determined. The Pel domains of the two predicted HrpW proteins were 85% identical, whereas the harpin domains were only 53% identical. Sequences hybridizing at high stringency with the P. syringae pv. tomato hrpW were found in other P. syringae pathovars, Pseudomonas viridiflava, Ralstonia (Pseudomonas) solanacearum, and Xanthomonas campestris. DeltahrpZ::nptII or hrpW::OmegaSpr P. syringae pv. tomato mutants were little reduced in HR elicitation activity in tobacco, whereas this activity was significantly reduced in a hrpZ hrpW double mutant. These features of hrpW and its product suggest that P. syringae produces multiple harpins and that the target of these proteins is in the plant cell wall. 相似文献
177.
178.
179.
Two premature female infants with a new variant of pulmonary hyaline membrane disease had both received assisted ventilation with high oxygen concentrations. Postmortem examination showed straw-yellow hyaline membranes lining the terminal bronchioles and alveoli. Pneumonocytes and macrophages also contained straw-yellow pigments in the cytoplasm. These yellow membranes and pigments in pneumonocytes and in macrophages stained positively for bile and negatively for iron. Both infants had severe intrahepatic cholestasis. Cholestasis and pulmonary changes due to oxygen toxicity are believed to be the main features leading to this curious entity. 相似文献
180.
Hirokadzu Taira 《Journal of the American Oil Chemists' Society》1985,62(4):699-702
The oil content and fatty acid composition of Virginia, Runner, and Spanish market types of peanuts imported into Japan were determined. The significant differences among the countries of production were shown in stearic, eicosenoic and lignoceric acid contents of Virginia market type and oil content and palmitic, stearic, oleic, linoleic, eicosenoic, behenic and lignoceric acid contents of Spanish market type. The Spanish market type, as compared with the Virginia market type, was significantly higher in palmitic, stearic, linoleic, arachidic and behenic acid contents and lower in oleic, eicosenoic and lignoceric acid contents on the gross samples. 相似文献