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991.
992.
993.
We report a case of mantle cell lymphoma in leukemic phase, which was diagnosed by a bone marrow biopsy performed as part of a workup for chronic anemia in a patient without lymphadenopathy. The patient, a 79-year-old man with diabetes mellitus, hypertension, chronic renal failure, congestive heart failure, and atherosclerosis, presented with claudication. On admission, he also had an 8-month history of anemia, during which time he experienced a 18-kg weight loss. On presentation, the patient had normal vital signs, anemia, leukocytosis (as well as an absolute lymphocytosis), and splenomegaly; as mentioned, lymphadenopathy was absent. A bone marrow biopsy showed an increase in small to intermediate-sized, slightly irregular lymphocytes in interstitial nodules. Flow cytometric immunophenotyping of the bone marrow identified a monoclonal population of cells, representing 25% of cells within the bone marrow, with expression of CD19, CD20, immunoglobulin M/D, lambda light chain, HLA-DR, and CD5; reactions for CD10 and CD23 were absent. Based on morphologic and immunophenotypic analysis of the bone marrow, as well as morphologic review of the peripheral blood smear, a diagnosis of mantle cell lymphoma involving the bone marrow and in leukemic phase was made. Subsequent polymerase chain reaction analysis of DNA from peripheral blood identified a population of cells with the bcl-1 rearrangement. This case is unique in that the diagnosis of mantle cell lymphoma was made without lymph node or spleen analysis and the patient, although exhibiting bone marrow and peripheral blood involvement by mantle cell lymphoma at presentation, did not have lymphadenopathy. 相似文献
994.
Resistance of adult C57BL/6 mice to severe Cryptosporidium parvum infection is dependent on CD4+alpha beta+ TCR lymphocytes. In this study, we demonstrated that treatment with anti-IFN-gamma mAb extended oocyst excretion 18 days longer, and anti-IL-4 mAb extended oocyst excretion at least 11 days longer than isotype control mAb treatment. Analysis of the specific activity of anti-IFN-gamma mAb present in treated mouse sera suggested that IFN-gamma may have a limited role in the resolution phase of infection. Changes were also documented in numbers of CD4+alpha beta+IFN-gamma+ and CD4+alpha beta+IL-4+ lymphocytes in Peyer's patches and intraepithelium of adult C57BL/6 mice during resolution of C. parvum infection. Resistance to initial severe infection was associated with CD4+alpha beta+IFN-gamma+ lymphocytes, and eventual resolution of infection was associated with CD4+alpha beta+IL-4+ lymphocytes. Analysis of cytokine expression following in vitro stimulation with C. parvum Ags during resolution of infection demonstrated consistent increases in CD4+alpha beta+IL-4+ lymphocytes, but not CD4+alpha beta+IFN-gamma+ lymphocytes. The relevance of CD4+alpha beta+IL-4+ lymphocytes in protection against C. parvum was then evaluated in C57BL/6 IL-4 gene knockout mice (IL-4(-/-)). Adult IL-4(-/-) mice excreted oocysts in feces approximately 23 days longer than IL-4(+/+) mice. Further, anti-IFN-gamma mAb treatment increased the severity and the duration of infection in IL-4(-/-) mice compared with those in IL-4(+/+) mice. Together, the data demonstrated that IFN-gamma was important in the control of severity of infection, and either IFN-gamma or IL-4 accelerated termination of infection. However, neither IL-4 nor IFN-gamma was required for the final clearance of infection from the intestinal tract of adult mice. 相似文献
995.
DS Keeney C Skinner JB Travers JH Capdevila LB Nanney LE King MR Waterman 《Canadian Metallurgical Quarterly》1998,273(48):32071-32079
The novel cytochrome P450, CYP2B19, is a specific cellular marker of late differentiation in skin keratinocytes. CYP2B19 was discovered in fetal mouse skin where its onset of expression coincides spatially (upper cell layer) and temporally (day 15.5) with the appearance of loricrin-expressing keratinocytes during the stratification stage of fetal epidermis. CYP2B19 is also present postnatally in the differentiated keratinocytes of the epidermis, sebaceous glands, and hair follicles. CYP2B19 mRNA is tightly coupled to the differentiated (granular cell) keratinocyte phenotype in vivo and in vitro. In primary mouse epidermal keratinocytes, it is specifically up-regulated and correlated temporally with calcium-induced differentiation and expression of the late differentiation genes loricrin and profilaggrin. Recombinant CYP2B19 metabolizes arachidonic acid and generates 14,15- and 11, 12-epoxyeicosatrienoic (EET) acids, and 11-, 12-, and 15-hydroxyeicosatetraenoic (HETE) acids (20, 35, 18, 7, and 7% of total metabolites, respectively). Arachidonic acid metabolism was stereoselective for 11S,12R- and 14S,15R-EET, and 11S-, 12R-, and 15R-HETE. The CYP2B19 metabolites 11,12- and 14,15-EET are endogenous constituents of murine epidermis and are present in similar proportions to that generated by the enzyme in vitro, suggesting that CYP2B19 might be the primary enzymatic source of these EETs in murine epidermis. 相似文献
996.
W Wang HJ Chen J Sun L Benimetskaya A Schwartz P Cannon CA Stein LE Rabbani 《Canadian Metallurgical Quarterly》1998,8(3):227-236
Biotinyl-oligosaccharides are a relatively new generation of saccharide probes that enable immobilization of desired oligosaccharides on streptavidin matrices for studies of carbohydrate-protein interactions. Here we describe the facile preparation of biotinyl-l-3-(2-naphthyl)-alanine hydrazide (BNAH) derivatives of oligosaccharides, containing a strong UV absorbing and fluorescent group, in which the ring of the reducing-end monosaccharide is nonreduced. We evaluate reactivities of immobilized BNAH- N -glycans with plant lectins that recognize aspects of the oligosaccharide core or outer-arms. We make some comparisons with 2-amino-6-amidobiotinyl-pyridine (BAP) derivatives obtained by reductive amination, and 6-(biotinyl)-aminocaproyl-hydrazide (BACH) derivatives which have a longer spacer-arm. N -Glycan-BNAH and-BAP derivatives have, overall, comparable reactivities with lectins which recognize N -glycan outer-arms or the trimannosyl core, but only BNAH and BACH derivatives are bound by lectins which recognize the non-reduced core. Moreover, with Pisum sativum agglutinin (PSA) which additionally requires the fucosyl- N- glycan-asparaginyl core for high affinity binding, the immobilized BNAH derivative (which is an alanine hydrazide beta-glycoside) can substitute for the natural beta-glycosylasparaginyl core, whereas the BACH derivative (aminocaproyl-hydrazide-beta-glycoside) is less effective. BNAH is a derivatization reagent of choice, therefore, for solid phase carbohydrate-binding experiments with immobilized N -glycans. 相似文献
997.
J Strain CR Lorenz J Bode S Garland GA Smolen DT Ta LE Vickery VC Culotta 《Canadian Metallurgical Quarterly》1998,273(47):31138-31144
Yeast deficient in the cytosolic copper/zinc superoxide dismutase (SOD1) exhibit metabolic defects indicative of oxidative damage even under non-stress conditions. To help identify the endogenous sources of this oxidative damage, we isolated mutant strains of S. cerevisiae that suppressed metabolic defects associated with loss of SOD1. Six complementation groups were isolated and three of the corresponding genes have been identified. One sod1Delta suppressor represents SSQ1 which encodes a hsp70-type molecular chaperone found in the mitochondria. A second sod1Delta suppressor gene, designated JAC1, represents a new member of the 20-kDa J-protein family of co-chaperones. Jac1p contains a mitochondrial targeting consensus sequence and may serve as the partner for Ssq1p. Homologues of Ssq1p and Jac1p are found in bacteria in close association with genes proposed to be involved in iron-sulfur protein biosynthesis. The third suppressor gene identified was NFS1. Nfs1p is homologous to cysteine desulfurase enzymes that function in iron-sulfur cluster assembly and is also predicted to be mitochondrial. Each of the suppressor mutants identified exhibited diminished rates of respiratory oxygen consumption and was found to have reduced mitochondrial aconitase and succinate dehydrogenase activities. Taken together these results suggest a role for Ssq1p, Jac1p, and Nfs1p in assembly/maturation of mitochondrial iron-sulfur proteins and that one or more of the target Fe/S proteins contribute to oxidative damage in cells lacking copper/zinc SOD. 相似文献
998.
T Eliasson C Mannheimer F Waagstein B Andersson CH Bergh LE Augustinsson T Hedner G Larson 《Canadian Metallurgical Quarterly》1998,89(3):170-177
OBJECTIVE: The authors determine if the intraoperative placement of paclitaxel powder in the subconjunctival space improves the outcome of glaucoma filtration surgery in rabbits. METHODS: A posterior lip sclerectomy was performed in the right eye of 24 New Zealand white rabbits. Before the conjunctiva was fully sutured, 8 mg of mannitol powder alone, or 8 mg of mannitol powder containing either 10 micrograms or 250 micrograms of paclitaxel, was placed in the subconjunctival space of six eyes each in masked fashion. An additional six animals were treated with episcleral application of a sponge soaked in a solution of 0.5 mg/ml of mitomycin C (MMC) for 5 minutes before the sclerectomy was performed. Intraocular pressure and bleb size were measured until the operation had failed or until the 7 weeks of observation had concluded. RESULTS: Both paclitaxel powder and MMC solution improved the outcome of filtration surgery in this model as measured by magnitude of intraocular pressure (IOP) lowering and duration of surgical success. No toxic effect of either drug was observed, although endophthalmitis was observed in eight animals followed for more than 3 weeks. CONCLUSION: The introduction of paclitaxel into the subconjunctival space at the conclusion of filtration surgery has an effect comparable to intraoperative MMC. 相似文献
999.
B L?sse H Kuhn D Rafflenbeul H Kr?nert W Hort LE Feinendegen F Loogen 《Canadian Metallurgical Quarterly》1980,69(8):523-530
36 consecutive patients with chest pain and/or severe ventricular dysrhythmias, but normal coronary arteries and normal left ventriculogram, underwent thallium-201 myocardial imaging at rest and during exercise. The myocardial scintigram was abnormal in 27 patients (group A) and normal in only 9 patients patients (group B). To answer the question, whether the scintigram was false positive or a correct expression of a myocardial disorder not detectable with angiocardiographic methods, we compared the scintigraphic results with the findings of resting and exercise ECG (n = 36), mean pulmonary artery pressure during exercise (n = 27), myocardial lactate extraction during highrate atrial pacing (n = 14) and light- and electronmicropic examination of right ventricular endomyocardial biopsies (n = 14). The resting ECG was abnormal in 7 of 27 patients of group A and 1 of 9 patients of group B, the exercise ECG in 20 of 27 patients of group A and 1 of 9 patient B. An abnormally elevated exercise pulmonary artery pressure was measured in 10 of 21 patients of group A and 1 of 6 patients of group B. High rate atrial pacing induced an abnormal myocardial lactate extraction in 3 of 13 patients of group A, but not in the single investigated patient of group B. All 12 examined patients of group A and 1 of 2 patients of group B had abnormal biopsy findings. The high incidence of abnormal findings in group A compared to the rare incidence in group B suggests, that the abnormal myocardial scintigrams in patients with chest pain and normal coronary arteries is likely not false positive but reflects a myocardial disorder not being recognized on angiography. 相似文献
1000.
Montgomery Lecture, 1975. Changing concepts of the prognosis and management of small malignant melanomas of the choroid 总被引:2,自引:0,他引:2
Recent studies have shown conclusively that patients with small choroidal melanomas tend to have a favourable prognosis and that this, in turn, is closely related to tumour cell type, mitotic activity, degree of trans-scleral extension, and other characteristics of the tumour. It has not yet been established whether enucleation of the tumour-containing eye increases or decreases the patient's chance for survival. The frequency with which we observe late metastatic deaths among patients who had seemingly been 'cured' by enucleation indicate that host factors are most important in determining whether or not a patient will succumb to his tumour. It is possible that nonsurgical methods of treatment may be as effective or even more effective than enucleation (a) by diminishing the changes of intravasation of tumour cells, and (b) by promoting a more favourable host response to the tumour. While the total experience in management by methods other than enucleation is small, the results reported to date with photocoagulation, radiation, and no therapy are encouraging. Only after a much larger experience with prolonged periods of evaluation (more than 10 years after recognition of the tumour) will we be able to compare the results with those obtained by enucleation. 相似文献