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21.
G W Sullivan H T Carper J A Sullivan T Murata G L Mandell 《Journal of leukocyte biology》1989,45(5):389-395
Both purified human monocyte interleukin-1 and recombinant interleukin-1 (beta) primed neutrophils for increased superoxide production and chemiluminescence in response to f-met-leu-phe. In addition, purified human monocyte interleukin-1 and recombinant interleukin-1 (beta) altered neutrophil shape. Recombinant interleukin-1 (alpha) used at the same concentration of interleukin-1 (beta) did not prime neutrophils for increased superoxide production after stimulation with f-met-leu-phe. Interleukin-1 expressed by monocytes in response to endotoxin stimulation could act as a modulator of neutrophil function. 相似文献
22.
Interchromosomal duplications of the adrenoleukodystrophy locus: a phenomenon of pericentromeric plasticity 总被引:13,自引:5,他引:13
Eichler EE; Budarf ML; Rocchi M; Deaven LL; Doggett NA; Baldini A; Nelson DL; Mohrenweiser HW 《Human molecular genetics》1997,6(7):991-1002
A 9.7 kb segment encompassing exons 7-10 of the adrenoleukodystrophy (ALD)
locus of the X chromosome has duplicated to specific locations near the
pericentromeric regions of human chromosomes 2p11,10p11, 16p11 and 22q11.
Comparative sequence analysis reveals 92-96% nucleotide identity,
indicating that the autosomal ALD paralogs arose relatively recently during
the course of higher primate evolution (5-10 million years ago). Analysis
of sequences flanking the duplication region identifies the presence of an
unusual GCTTTTTGC repeat which may be a sequence-specific integration site
for the process of pericentromeric- directed transposition. The breakpoint
sequence and phylogenetic analysis predict a two-step transposition model,
in which a duplication from Xq28 to pericentromeric 2p11 occurred once,
followed by a rapid distribution of a larger duplicon cassette among the
pericentromeric regions. In addition to facilitating more effective
mutation detection among ALD patients, these findings provide further
insight into the molecular basis underlying a pericentromeric-directed
mechanism for non- homologous interchromosomal exchange.
相似文献
23.
DL?MagerEmail author AD?Haffajee PM?Devlin CM?Norris MR?Posner JM?Goodson 《Journal of translational medicine》2005,3(1):27
Background
The purpose of the present investigation was to determine if the salivary counts of 40 common oral bacteria in subjects with an oral squamous cell carcinoma (OSCC) lesion would differ from those found in cancer-free (OSCC-free) controls. 相似文献24.
The simian immunodeficiency virus (SIV) nef gene is an important determinant of viral load and acquired immunodeficiency syndrome (AIDS) in macaques. A role(s) for the HIV-1 nef gene in infection and pathogenesis was investigated by constructing recombinant viruses in which the nef gene of the pathogenic molecular clone SIVmac239 nef was replaced with either HIV-1sf2nef or HIV-1sf33nef. These chimeras, designated SHIV-2nef and SHIV-33nef, expressed HIV-1 Nef protein and replicated efficiently in cultures of rhesus macaque lymphoid cells. In two SHIV-2nef-infected juvenile rhesus macaques and in one of two SHIV-33nef-infected juvenile macaques, virus loads remained at low levels in both peripheral blood and lymph nodes in acute and chronic phases of infection (for >83 weeks). In striking contrast, the second SHIV-33nef-infected macaque showed high virus loads during the chronic stage of infection (after 24 weeks). CD4+ T-cell numbers declined dramatically in this latter animal, which developed simian AIDS (SAIDS) at 47-53 weeks after inoculation; virus was recovered at necropsy at 53 weeks and designated SHIV-33Anef. Sequence analysis of the HIV-1sf33 nef gene in SHIV-33Anef revealed four consistent amino acid changes acquired during passage in vivo. Interestingly, one of these consensus mutations generated a tyr-x-x-leu (Y-X-X-L) motif in the HIV-1sf33 Nef protein. This motif is characteristic of certain endocytic targeting sequences and also resembles a src-homology region-2 (SH-2) motif found in many cellular signaling proteins. Four additional macaques infected with SHIV-33Anef contained high virus loads, and three of these animals progressed to fatal SAIDS. Several of the consensus amino acid changes in Nef, including Y-X-X-L motif, were retained in these recipient animals exhibiting high virus load and disease. In summary, these findings indicate that the SHIV-33Anef chimera is pathogenic in rhesus macaques and that this approach, i.e., construction of chimeric viruses, will be important for analyzing the function(s) of HIV-1 nef genes in immunodeficiency in vivo, testing antiviral therapies aimed at inhibiting AIDS, and investigating adaptation of this HIV-1 accessory gene to the macaque host. 相似文献
25.
Inhibition of the inflammatory action of interleukin-1 and tumor necrosis factor (alpha) on neutrophil function by pentoxifylline. 总被引:14,自引:7,他引:14 下载免费PDF全文
Inflammatory cytokines, including interleukin-1 and tumor necrosis factor, are produced by monocytes and macrophages in response to microorganisms and microbial products such as endotoxins. The cytokines stimulate neutrophil adherence, degranulation, and superoxide production but inhibit neutrophil migration. We studied the modulation of cytokine-induced neutrophil activation by pentoxifylline and its principle metabolites. Lipopolysaccharide-stimulated mononuclear-leukocyte-conditioned medium containing inflammatory cytokines, purified human interleukin-1, or recombinant human tumor necrosis factor increased neutrophil adherence to nylon fiber, primed neutrophils for increased superoxide production in response to N-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP), increased neutrophil lysozyme release stimulated by FMLP, and decreased directed migration of neutrophils to FMLP. Pentoxifylline and its principle metabolites at or near therapeutically achievable levels were able to counteract these effects. Pentoxifylline inhibited the increase in free intracellular calcium in polymorphonuclear leukocytes stimulated by FMLP and increased binding of FMLP to neutrophils at 37 degrees C but not at 4 degrees C. By blocking the inflammatory action of interleukin-1 and tumor necrosis factor on neutrophils, pentoxifylline may diminish the tissue damage caused by neutrophils in such conditions as septic shock, adult respiratory distress syndrome, cardiopulmonary bypass lung damage, and myocardial reperfusion injury. 相似文献
26.
27.
0 引言 我科 1996 / 1998分别应用消痔灵与强的松龙混合液、消痔灵液、强的松龙液行鼻息肉内 ,鼻息肉蒂部注射治疗鼻息肉各 5 0例 ,并设对照组为鼻腔滴入及口服类固醇激素 5 0例 ,合计 2 0 0例 ,观察并对比其疗效 .1 对象和方法1.1 对象 男 12 8例 ,女 72例 ,年龄 8~ 78(平均 38)岁 ,病程 32 a~ 45 (平均 4.5 ) a.其中在本次治疗前做过一次鼻息肉摘除术后复发的 2 7例 ,做过 2次或 2次以上手术的 12例 .主要症状为鼻塞、流脓涕、头痛及嗅觉减退 .全部病例治疗前均行鼻窦 X线拍片 ,其中上颌窦炎 12 5例、筛窦炎 5 8例、蝶窦炎 2例、… 相似文献
28.
Sinus histiocytosis (Rosai-Dorfman disease) of the suprasellar region: MR imaging findings--a case report 总被引:2,自引:0,他引:2
Sinus histiocytosis with massive lymphadenopathy (SHML) is an uncommon disorder that typically manifests as systemic symptoms and lymphadenopathy. Extranodal, intracranial disease is uncommon. The authors report on a 15-year-old adolescent girl who had a suprasellar mass at magnetic resonance imaging. Biopsy results demonstrated lymphophagocytosis consistent with a diagnosis of SHML. The clinical, radiologic, and histologic aspects of the disease are discussed. 相似文献
29.
Reactive astrogliosis is the most prominent macroglial response to diverse forms of CNS injury. We assessed a potential role for the extracellular signal-regulated kinase/mitogen-activated protein kinase (ERK/MAPK) pathway because it represents a common effector for several major families of transmembrane receptors implicated in astrogliosis. Immunohistochemical detection of activated ERK/MAPK in a series of human neurosurgical specimens utilizing phosphorylation state-dependent antibodies consistently revealed intense immunoreactivity in reactive astrocytes in both subacute and chronic lesions, including infarct, mechanical trauma, chronic epilepsy, and progressive multifocal leukoencephalopathy. Neurons, oligodendroglia, and most inflammatory cells showed little or no detectable activation. These observations suggest a testable hypothesis: activation of the ERK/MAPK pathway is an obligatory step for the triggering and/or persistence of reactive astrogliosis. 相似文献
30.
Reliability of Doppler color flow mapping in the identification and localization of multiple ventricular septal defects 总被引:1,自引:0,他引:1
Spevak PJ Mandell VS Colan SD Van Der Velde ME Jonas RA Lock JE Sanders SP 《Echocardiography (Mount Kisco, N.Y.)》1993,10(6):573-581
The purpose of this study was to compare Doppler color flow mapping with angiography and surgical observation for detection of multiple ventricular septal defects (VSDs). Only patients with elevated pulmonary ventricular pressure were included. Among 137 patients with VSDs, 38 multiple defects were identified in 25 patients echocardiographically, 34 multiple defects in 24 patients angiographically, and 21 multiple defects in 17 patients surgically. Using surgical observation as the reference standard, the sensitivity of echocardiography for identifying patients with multiple VSDs was 17 of 17 (100%) and for angiography 15 of 17 (88%). The sensitivity of echocardiography for identifying all multiple VSDs seen at operation was 19 of 21 (90%) and of angiography was also 19 of 21 (90%). In many patients, use of both techniques may no longer be necessary. 相似文献