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Chelsea E. Matisz Cameron P. Goater Douglas Bray 《International journal for parasitology》2010,40(3):307-312
Evidence for the presumed linkage between the enigmatic rodlet cells of fish and exposure to helminths is anecdotal and indirect. We evaluated the proliferation and development of rodlet cells in the optic lobes of fathead minnows exposed to cercariae of Ornithodiplostomum ptychocheilus. Mean rodlet cell densities (ca. 10/mm2) in the optic lobes were similar between unexposed controls and minnows with 1- and 2-week old infections. Rodlet cell densities increased at 4 weeks p.i., reaching maxima (ca. 200/mm2) at 6 weeks p.i., followed by a decline at 9 weeks. This temporal pattern of proliferation and maturation paralleled the development of metacercariae within the optic lobes. Unencysted metacercariae develop rapidly within tissues of the optic lobes for approximately 4 weeks after penetration by cercariae, then shift to the adjacent meninges to encyst. The former stage is associated with tissue damage, the latter with massive inflammation of the meninges. Thus, peak densities and maturation of rodlet cells correspond to the period when inflammation of the meninges caused by the large metacercarial cysts is at a maximum. Our results support recent contentions that rodlet cells comprise part of the host inflammatory defence response. 相似文献
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Cell wall residues in yeast protoplast preparations 总被引:5,自引:2,他引:3
Protoplast preparations made from Saccharomyces cerevisiae by prolonged treatment with snail digestive juice contained fibrils and chitinous bud-scar residues from the original cell wall. 相似文献
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B-F alloantisera recognized distinct 45-Kd molecules on peripheral red blood cells (RBC) from embryonic chickens and heterogeneous molecules of approximately 40 to 44 Kd on peripheral RBC from adult chickens, provisionally referred to as type 1 and type 2, respectively. Type 2 molecules migrated to the basic end of isoelectric focusing gels, exhibited multiple isomorphic variants, and were associated with a smaller polypeptide of approximately 11 to 12 Kd assumed to be beta-2-microglobulin. Type 1 molecules migrated to the acidic end of isoelectric focusing gels, exhibited limited heterogeneity, and were not associated with a smaller polypeptide. Type 1 and type 2 molecules were also shown to be distinct by peptide mapping and serological analyses. In addition, two distinct molecular-weight forms of the type 2 molecules were distinguished, provisionally referred to as 2A (45 Kd) and 2B (42 Kd). In vivo-derived avian erythroblastosis virus (AEV)-transformed erythroleukemia cells expressed type 2A molecules. In vitro-derived AEV-transformed erythroleukemia cells expressed very low levels of B-F molecules; however, they expressed type 2B molecules when induced to differentiate. Normal bursa-derived lymphoid cells expressed type 2A molecules, whereas normal thymus-derived lymphoid cells expressed type 2B molecules. Cloned reticuloendotheliosis virus (REV)-transformed immature lymphoid cells expressed either type 2A or type 2B molecules. 相似文献
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C L Hall S Jawad P R Harrison J C MacKenzie P A Bacon P T Klouda A G MacIver 《BMJ (Clinical research ed.)》1988,296(6629):1083-1086
To elucidate the natural course of the nephropathy associated with penicillamine and thereby facilitate its clinical management 33 patients with rheumatoid arthritis who developed proteinuria during treatment with oral penicillamine were studied in detail throughout their renal illness. Renal biopsies were performed, and creatinine clearance and proteinuria were measured serially for 74 months (range 16-148 months). Fourteen patients developed proteinuria within six months after the start of treatment and 27 within 12 months. When treatment was stopped the proteinuria reached a median peak of 4·2 g/24 h (range 0·3-15·0 g/24 h) at one month (range 0-7 months) before resolving spontaneously by six months (12 patients), 12 months (21), or 18 months (29). In all patients but one, who developed carcinoma of the renal pelvis, proteinuria resolved by 21 months and its median duration was eight months. The median first and last measurements of creatinine clearance showed no appreciable change (80 ml/min and 78 ml/min), and no patient died from or needed treatment for renal failure. The HLA-B8 or HLA-DR3 alloantigen, or both, were identified in 10 patients. Renal biopsy specimens showed membranous glomerulonephritis in 29 patients, minimal change nephropathy in two, and electron dense deposits in the mesangial regions in two.In all the patients whose nephropathy was due solely to treatment with penicillamine the proteinuria resolved completely when the drug was withdrawn; renal function did not deteriorate, and corticosteroids were unnecessary. 相似文献
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Differential cytotoxicity and mycotoxin content among isolates of Fusarium moniliforme 总被引:1,自引:1,他引:0
William P. Norred Charles W. Bacon Ronald D. Plattner Ronald F. Vesonder 《Mycopathologia》1991,116(1):37-43
Curvularia lunata was found causing (disseminated phaeohyphomycosis among a group of Nezara viridula (Insecta:Heteroptera) parasitizing vegetable crop Vigna unguiculata. Dark lesions were seen on pronotum and abdominal sterna. Experimental lesions were produced by applying 0.1 ml of 6.2 × 108cfu/ml–1 on abdominal sterna. Histopathology revealed that almost all internal organs and tissues showed extensive damage. It is interesting to note that C. lunata exhibited predeliction for chitinous tissues and elicited cellular immune response by granulocytes (phagocytosis). This is the first report of phaeohyphomycosis of an insect, extending the disease to invertebrates.A promising research career of one of the authors (Mrs. Vinita Dubey) was cut short by untimely death. This paper is dedicated to her memory. 相似文献
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Multiple sequence alignment 总被引:13,自引:0,他引:13
A method has been developed for aligning segments of several sequences at once. The number of search steps depends only polynomially on the number of sequences, instead of exponentially, because most alignments are rejected without being evaluated explicitly. A data structure herein called the "heap" facilitates this process. For a set of n sequence segments, the overall similarity is taken to be the sum of all the constituent segment pair similarities, which are in turn sums of corresponding residue similarity scores from a Table. The statistical models that test alignments for significance make it possible to group sequences objectively, even when most or all of the interrelationships are weak. These tests are very sensitive, while remaining quite conservative, and discourage the addition of "misfit" sequences to an existing set. The new techniques are applied to a set of five DNA-binding proteins, to a group of three enzymes that employ the coenzyme FAD, and to a control set. The alignment previously proposed for the DNA-binding proteins on the basis of structural comparisons and inspection of sequences is supported quite dramatically, and a highly significant alignment is found for the FAD-binding proteins. 相似文献