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41.
42.
Effect of selenium supplementation on mice infected with LP-BM5 MuLV, a murine AIDS model 总被引:2,自引:0,他引:2
Chumyimg Chen Jinyan Zhou Huibi Xu Yam Jiang Guanfu Zhu 《Biological trace element research》1997,59(1-3):187-193
LP-BM5 Murine leukemia virus (MuLV) infection of C57BL/6 mice develop a disease that has many features in common with human
acquired immunodeficiency syndrome (AIDS), in particular abnormal lymphoproliferation and severe immunodeficiency. Thus, this
MAIDS model may be useful for evaluation of potent antirival agents in vivo. Deficiency in antioxidant micronutients such
as selenium, zinc, and glutathione have been observed in AIDs and AIDS-related complex (ARC) patients. In the present study,
the MAIDS model was used to evaluate immunological and oxidative effect of Se as sodium selenite. Results indicated that Se
treatment 0.1 mg/kg/d (p.o.) inhibited splenomegaly and sera IgG elevation effectively. In addition to abnormal immunity,
oxidative imbalance possibly existed in MAIDS model, as lipid peroxide increased significantly in spleen and whole blood glutathione
peroxidase (GSH-Px) activity decreased markedly. Se supplementation had good protective effect. 相似文献
43.
Thomas GH; Newbern EC; Korte CC; Bales MA; Muse SV; Clark AG; Kiehart DP 《Molecular biology and evolution》1997,14(12):1285-1295
Many structural, signaling, and adhesion molecules contain tandemly
repeated amino acid motifs. The alpha-actinin/spectrin/dystrophin
superfamily of F-actin-crosslinking proteins contains an array of triple
alpha-helical motifs (spectrin repeats). We present here the complete
sequence of the novel beta-spectrin isoform beta(Heavy)- spectrin (beta H).
The sequence of beta H supports the origin of alpha- and beta-spectrins
from a common ancestor, and we present a novel model for the origin of the
spectrins from a homodimeric actin-crosslinking precursor. The pattern of
similarity between the spectrin repeat units indicates that they have
evolved by a series of nested, nonuniform duplications. Furthermore, the
spectrins and dystrophins clearly have common ancestry, yet the repeat unit
is of a different length in each family. Together, these observations
suggest a dynamic period of increase in repeat number accompanied by
homogenization within each array by concerted evolution. However, today,
there is greater similarity of homologous repeats between species than
there is across repeats within species, suggesting that concerted evolution
ceased some time before the arthropod/vertebrate split. We propose a
two-phase model for the evolution of the spectrin repeat arrays in which an
initial phase of concerted evolution is subsequently retarded as each new
protein becomes constrained to a specific length and the repeats diverge at
the DNA level. This evolutionary model has general applicability to the
origins of the many other proteins that have tandemly repeated motifs.
相似文献
44.
Serial studies were done on cerebrospinal fluid (CSF) from a patient with sarcoidosis involving the meninges. Initially when the disease was active, the CSF protein was increased and glucose decreased. The number of cells in the CSF was moderately increased, and many mononuclear cells were present. Cytologic studies of the CSF showed many normal and some atypical lymphocytes. Immunochemical studies showed that most of these lymphocytes were T cells, with T-helper cells predominating over T-suppressor cells by a ratio of 3.92; B-lymphocytes were polyclonal. Subsequent studies of the CSF over the following three and one-half years showed that the protein and glucose content and the cell counts in the fluid did not correlate well with the activity of the disease. The number of atypical lymphocytes seemed to be a more useful marker of disease activity in the patient. Cytologic studies, when interpreted within the context of other CSF and clinical findings, are useful for the assessment of patients with sarcoidosis involving the meninges. 相似文献
45.
In a patient with chronic myeloid leukemia in blastic transformation, the blast cells in a knee joint effusion were identical morphologically to those in the marrow. Cytochemical and immunocytochemical studies showed that these blasts were primitive erythroblasts and not granulocytic or monocytic precursors. The combined use of cytologic, cytochemical and immunocytochemical techniques will help to accurately identify cells in joint effusions and to elucidate the mechanism of synovial involvement by hematologic disorders. 相似文献
46.
Anthony J Janckila Wen-Kuang Yang Ruey-Jen Lin Chia-Jen Tseng Hsin-Yu Chang Jia-Ming Chang Lung T Yam 《The journal of histochemistry and cytochemistry》2003,51(9):1131-1137
Tartrate-resistant acid phosphatase (TRACP) is a cytochemical marker for hairy cell leukemia, macrophages, dendritic cells, and osteoclasts. Our purpose was to develop multicolor cytofluorometric methods to evaluate intracellular TRACP enzymic activity using a fluorogenic cytochemical reaction in combination with immunochemical stains for distinct surface membrane antigens. Monocyte-derived dendritic cells (DCs) were the model TRACP-expressing cells studied. Intracellular TRACP activity was disclosed using naphthol-ASBI phosphate as substrate with fast red-violet LB salt as coupler for the reaction product. Before the TRACP enzymic reaction, surface antigens, CD86 and CD11c of DCs, were bound with specific fluorescent antibodies to test compatibility of surface labeling and intracellular staining. TRACP activity varied in DCs from donor to donor but was reproducible on repeated examinations of each sample. Samples could be stained for simultaneous analysis of surface antigens and intracellular TRACP activity, provided certain technical details were observed. The TRACP reaction time should not exceed 9 min and the cell number should not exceed 2 x 10(5)/100 micro l test. Fluorescent surface labels did not affect the intensity of the TRACP stain, but the intensity of some surface labels may be diminished by elution of low-affinity antibodies during the TRACP reaction. Readjustment of the threshold settings in triple-labeled cells is needed to compensate for this phenomenon. Intracellular TRACP activity can be quantitated in subpopulations of cells within mixed cell populations by flow cytofluorometry using simple cytochemical methods in combination with fluorescent antibodies to cell-surface and other differentiation antigens. The cytochemical method should be useful for basic investigations of differentiation, maturation, and function of macrophages, DCs, and osteoclasts, and for diagnosis and management of hairy cell leukemia. 相似文献
47.
Nina Seidelmann Daniela F. Duarte Campos Malena Rohde Sandra Johnen Sabine Salla Gary Hin-Fai Yam Jodhbir S. Mehta Peter Walter Matthias Fuest 《Journal of cellular and molecular medicine》2021,25(20):9647-9659
The isolation and propagation of primary human corneal stromal keratocytes (CSK) are crucial for cellular research and corneal tissue engineering. However, this delicate cell type easily transforms into stromal fibroblasts (SF) and scar inducing myofibroblasts (Myo-SF). Current protocols mainly rely on xenogeneic fetal bovine serum (FBS). Human platelet lysate (hPL) could be a viable, potentially autologous, alternative. We found high cell survival with both supplements in CSK and SF. Cell numbers and Ki67+ ratios increased with higher fractions of hPL and FBS in CSK and SF. We detected a loss in CSK marker expression (Col8A2, ALDH3A1 and LUM) with increasing fractions of FBS and hPL in CSK and SF. The expression of the Myo-SF marker SMA increased with higher amounts of FBS but decreased with incremental hPL substitution in both cell types, implying an antifibrotic effect of hPL. Immunohistochemistry confirmed the RT-PCR findings. bFGF and HGF were only found in hPL and could be responsible for suppressing the Myo-SF conversion. Considering all findings, we propose 0.5% hPL as a suitable substitution in CSK culture, as this xeno-free component efficiently preserved CSK characteristics, with non-inferiority in terms of cell viability, cell number and proliferation in comparison to the established 0.5% FBS protocol. 相似文献
48.
Immunocytochemical studies were performed in order to accurately recognize the origin of tumor cells in a pleural effusion from a patient with a mediastinal mass. The immunoalkaline phosphatase technique was employed to examine several cell-specific surface antigens via their specific monoclonal antibodies. The tumor cells in this case did not have any demonstrable antigens of the human blood cells but did have abundance of an antigen specific for the tumor cells of oat-cell carcinoma. This diagnosis obtained by the immunochemical studies was confirmed by both cytologic and clinical findings. Immunocytochemical studies may become a mainstay for specific cytodiagnosis in the future. 相似文献
49.
Annemarie MM Vlaar Marinus JPG van Kroonenburgh Alfons GH Kessels Wim EJ Weber 《BMC neurology》2007,7(1):27
Background
Parkinson's disease (PD) is the second most common neurodegenerative disorder. One of the most widely used techniques to diagnose PD is a Single Photon Emission Computer Tomography (SPECT) scan to visualise the integrity of the dopaminergic pathways in the brain. Despite this there remains some discussion on the value of SPECT in the differential diagnosis of PD. We did a meta-analysis of all the existing literature on the diagnostic accuracy of both pre- and post-synaptic SPECT imaging in the differential diagnosis of PD. 相似文献50.