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101.
The development of total biliary casts is very unusual, especially in patients who have not undergone liver transplantation. The aetiology of these casts is uncertain but several factors are believed to play a role, including periods of fasting, haemolysis, cholangitis and recent surgery. Resultant bile stasis and/or gallbladder hypocontractility promote sludge and subsequent stone formation. Here we present the case of a previously well 66-year-old woman who developed a total biliary cast several weeks after being involved in a road traffic accident during which she sustained head injuries but no obvious liver insult. This cast was removed at laparotomy but the patient had resultant diffuse biliary tree abnormalities and persistent cholestasis and subsequently required a liver transplant. The possible aetiologies of biliary cast formation and subsequently cholangiopathy necessitating transplantation in this patient are described.  相似文献   
102.
Gay  JC; Beckman  JK; Brash  AR; Oates  JA; Lukens  JN 《Blood》1984,64(4):780-785
Leukotriene B4 (LTB4) is a potent primary stimulator of neutrophil chemotaxis, aggregation, and degranulation and induces superoxide production at higher concentrations. In order to determine whether LTB4 modulates neutrophil responses to oxidative stimuli, human neutrophils (PMNs) were incubated with LTB4 prior to stimulation with f-Met-Leu-Phe (fMLP, 10(-7) mol/L), opsonized zymosan (OZ, 250 micrograms/mL), or phorbol myristate acetate (PMA, 32 nmol/L). Superoxide (O2-) production by stimulated PMNs was assessed by the superoxide dismutase-inhibitable reduction of cytochrome c. LTB4 alone did not stimulate O2- production in concentrations below 10(-7) mol/L and had no effect on the O2- assay. In the concentration range of 10(-12) to 10(-8) mol/L, LTB4 did not alter O2- release induced by OZ or PMA. In contrast, LTB4-treated cells demonstrated enhanced O2- production following exposure to fMLP, and in the presence of 10 nmol/LLTB4, generated 180% +/- 41% of O-2 quantities produced by control cells (n = 23). Enhancement was LTB4 dose-dependent, was maximal in the range of 1 to 10 nmol/L LTB4, was not reversed by removal of the lipid from the medium prior to fMLP stimulation, and was not dependent on the presence of Ca++ or Mg++ in the suspending medium. Chemiluminescence of fMLP-stimulated neutrophils was increased to 323% of controls in neutrophils preincubated with 10 nmol/L LTB4. Unlike augmentation of oxidative responses to fMLP seen with other degranulating stimuli, enhancement by LTB4 was not correlated with an increase in 3H-fMLP receptor binding. These results indicate that, in addition to its primary effects on neutrophil function, LTB4 modulates PMN oxidative responses to the chemotactic peptide and, thus, may amplify the release of oxygen metabolites at inflammatory foci.  相似文献   
103.
Various mycobacteria were tested for their ability to retain acid-fastness after treatment with pyridine: a) Mycobacterium leprae separated from organs of 20 experimentally infected armadillos (which were sacrificed); b) M. leprae separated from a biopsy of a lepromatous patient; c) direct smears of lepromatous tissues from armadillos; d) eighteen cultivable mycobacteria obtained from the American Type Culture Collection (ATCC); E) cultivatable mycobacteria separated from the lymph nodes of a wild-caught armadillo and also the same organism grown in culture and Skinsnes' alleged M. leprae culture. A loss of acid-fastness was observed microscopically from M. leprae separated from experimentally infected armadillo tissues, M. leprae separated from a lepromatous patient biopsy, and M. leprae found in direct smears prepared from infected armadillo tissues. The eighteen cultivatable mycobacteria from ATCC, cultivatable mycobacteria separated from the tissue of a wild-caught armadillo (and also grown in culture) and Skinsnes' alleged M. leprae culture retained their acid-fastness. Testing of pyridine extractability of acid-fastness combined with those of D-DOPA oxidase testing proved to be extremely reliable in our laboratory in differentiating M. leprae from other mycobacteria.  相似文献   
104.
Plant-made vaccines have been the subject of intense interest because they can be produced economically in large scale without the use of animal-derived components. Plant-made therapeutic vaccines against challenging chronic diseases, such as cancer, have received little research attention, and no previous human clinical trials have been conducted in this vaccine category. We document the feasibility of using a plant viral expression system to produce personalized (patient-specific) recombinant idiotype vaccines against follicular B cell lymphoma and the results of administering these vaccines to lymphoma patients in a phase I safety and immunogenicity clinical trial. The system allowed rapid production and recovery of idiotypic single-chain antibodies (scFv) derived from each patient's tumor and immunization of patients with their own individual therapeutic antigen. Both low and high doses of vaccines, administered alone or co-administered with the adjuvant GM-CSF, were well tolerated with no serious adverse events. A majority (>70%) of the patients developed cellular or humoral immune responses, and 47% of the patients developed antigen-specific responses. Because 15 of 16 vaccines were glycosylated in plants, this study also shows that variation in patterns of antigen glycosylation do not impair the immunogenicity or affect the safety of the vaccines. Collectively, these findings support the conclusion that plant-produced idiotype vaccines are feasible to produce, safe to administer, and a viable option for idiotype-specific immune therapy in follicular lymphoma patients.  相似文献   
105.
Carotid artery angioplasty and stent placement (CAS) can be complicated by procedure-related distal embolization and thrombus formation, potentially resulting in neurological sequelae. Patient A had CAS of left internal carotid artery and had loss of vision in the left eye with no flow in the left ophthalmic artery. Patient B had CAS of right internal carotid artery and developed left sided hemiparesis with total occlusion of the right middle cerebral artery. A selective intra-arterial injection of 5 mg of abciximab locally followed by a bolus of 5 mg of abciximab intravenously resulted in complete resolution of the filling defect on repeat angiography after 10 min in both patients.  相似文献   
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Mouse mast cells express gp49B1, a cell-surface member of the Ig superfamily encoded by the gp49B gene. We now report that by ALIGN comparison of the amino acid sequence of gp49B1 with numerous receptors of the Ig superfamily, a newly recognized family has been established that includes gp49B1, the human myeloid cell Fc receptor for IgA, the bovine myeloid cell Fc receptor for IgG2, and the human killer cell inhibitory receptors expressed on natural killer cells and T lymphocyte subsets. Furthermore, the cytoplasmic domain of gp49B1 contains two immunoreceptor tyrosine-based inhibition motifs that are also present in killer cell inhibitory receptors; these motifs downregulate natural killer cell and T-cell activation signals that lead to cytotoxic activity. As assessed by flow cytometry with transfectants that express either gp49B1 or gp49A, which are 89% identical in the amino acid sequences of their extracellular domains, mAb B23.1 was shown to recognize only gp49B1. Coligation of mAb B23.1 bound to gp49B1 and IgE fixed to the high-affinity Fc receptor for IgE on the surface of mouse bone marrow-derived mast cells inhibited exocytosis in a dose-related manner, as defined by the release of the secretory granule constituent beta-hexosaminidase, as well as the generation of the membrane-derived lipid mediator, leukotriene C4. Thus, gp49B1 is an immunoreceptor tyrosine-based inhibition motif-containing integral cell-surface protein that downregulates the high-affinity Fc receptor for IgE-mediated release of proinflammatory mediators from mast cells. Our findings establish a novel counterregulatory transmembrane pathway by which mast cell activation can be inhibited.  相似文献   
110.
The intradermal administration of complete Freund's adjuvant (CFA) containing Mycobacterium butyricum to Sprague-Dawley (SD) and Lewis strain rats results in polyarthritis and uveitis. Over 90% of the eyes examined from the SD rats given CFA had histologic evidence of anterior uveitis, clinically evident in only 20 to 28%. Many rats developed arthritis without clinical uveitis, but uveitis was rare in the absence of arthritis. Histologically, the ocular inflammation was characterized by a polymorphonuclear, and later, a lymphocytic infiltration of the iris and ciliary body with cells and fibrinous exudate in the anterior chamber and cells in the vitreous. Antibodies and cellular immunity to ocular (S antigen, alpha crystallin), articular (type II collagen, proteoglycan) and bacterial components (MDP), were demonstrated in some rats, but positive tests did not correlate with either articular or ocular disease. Ten percent of rats given type II collagen in incomplete Freund's adjuvant developed uveitis. Thus, the pathogenesis of the arthritis and uveitis in the adjuvant model may be mediated by lymphocytes which exhibit crossreactivity with antigens in these structures, although the specificity of such antigens has not been identified in our studies.  相似文献   
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