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101.
Association of granulocyte-macrophage colony-stimulating factor with the crystalloid granules of human eosinophils 总被引:3,自引:1,他引:3
Levi-Schaffer F; Lacy P; Severs NJ; Newman TM; North J; Gomperts B; Kay AB; Moqbel R 《Blood》1995,85(9):2579-2586
We have previously shown that normal-density human peripheral blood eosinophils transcribe and translate mRNA for granulocyte-macrophage colony-stimulating factor (GM-CSF) and that the intracellular distribution was granular as assessed by light microscopy immunocytochemistry. The present study was conducted to confirm this apparent association between GM-CSF and the crystalloid granule using a subcellular fractionation method for human eosinophils and immunogold electron microscopy (EM). Highly purified (> 99%, by negative selection using anti-CD16 immunomagnetic microbeads) human peripheral blood eosinophils were obtained from four asthmatic subjects (not taking systemic medication), homogenized and density fractionated (5 x 10(7) cells/subject) on linear Nycodenz gradients. Twenty-four fractions were collected from each cell preparation and analyzed for marker enzyme activities as well as total protein. Dot blot analysis with specific monoclonal antibodies (MoAbs) was used to detect the eosinophil granule proteins major basic protein (MBP) and eosinophil cationic protein (ECP). An anti-CD9 MoAb was used as an eosinophil plasma membrane marker. Lactate dehydrogenase (LDH) was used as a cytosolic marker. Immunoreactivity for GM-CSF was detected by a specific enzyme-linked immunosorbent assay using a polyclonal antihuman GM-CSF antibody and confirmed by dot blot. GM-CSF coeluted with the cellular fractions containing granule markers (MBP, ECP, eosinophil peroxidase, hexosaminidase, and arylsulphatase), but not those containing cytoplasm (LDH+) or membrane (CD9+) markers. EM examination of pooled fractions associated with the peak of GM-CSF immunoreactivity confirmed that they contained crystalloid and small granules, but not plasma membrane. In addition, quantification, using immunogold labeling with an anti/GM-CSF MoAb, indicated preferential localization of gold particles over the eosinophil granule cores of intact cells. Thus, our results indicate that GM-CSF resides as a granule-associated, stored mediator in unstimulated human eosinophils. 相似文献
102.
Down-regulation of mannosyl receptor-mediated endocytosis and antigen F4/80 in bacillus calmette-guerin-activated mouse macrophages. Role of T lymphocytes and lymphokines 总被引:2,自引:1,他引:2 下载免费PDF全文
Bacillus Calmette-Guerin (BCG) infection alters the surface and endocytic properties of mouse peritoneal macrophages (PM) compared with thioglycollate- elicited (TPM) or resident PM (RPM). Expression of Ia antigen (Ag) is enhanced up to fourfold, but plasma membrane receptors that mediate binding and uptake of mannosyl/fucosyl-terminated glycoconjugates (MFR), Fc receptors, and the macrophage (m)-specific Ag F4/80 are reduced by 50-80 percent. Levels of Mac-1 remain relatively stable. These changes are accompanied by enhanced secretion of O(2)(-), after further stimulation with phorbyl myristate acetate, and of plasminogen activator. Both these products are released by TPM, but not RPM. The characteristic surface phenotype of BCG-PM can also be induced by injection of C. parvum, another m- activating agent, but not by thioglycollate broth, lipopolysaccharide, or proteose peptone. Purified protein derivative (PPD) and N-acetylmuramyl-L- alanyl-D-isoglutamine. 2H(2)0 are soluble agents with partial activity. Alteration of m markers by BCG infection depends on T lymphocyte function, although studies with nude mice indicate that other pathways may also serve to modify the surface of the m. M from uninfected animals displayed all markers of activation after adoptive transfer of specifically-sensitised lymphocytes with PPD, intraperitoneally, or after co- cultivation. Treatment of primed lymphocytes with anti-Thy-1 antibody and complement ablated this effect. Lymphokines obtaned by Ag or mitogen stimulation induced similar changes in TPM and RPM. Mannose-specific endocytosis decayed rapidly, time 1/2 approximately equal to 16 h and stabilized at approximately 25 percent of control values. Single-cell analysis showed that residual MFR activity was uniform in the target population. Loss of Ag F4/80 after activation by lymphocyte and PPD was less marked than after infection (35 percent vs 80 percent), unlike MFR activity, which declined to a similar extent. Induction of m Ia by lymphokine reached a peak after 2-3 d and was lost within 2 d of its removal. Recovery of MFR and F4/80 was incomplete under these conditions. These studies establish that activated m known to display enhanced antimicrobial/anticellular activity express markedly different surface properties distinct from elicited or resident cells. The role of antigen- stimulated T cell products in regulating m function is confirmed, and down-regulation of mannosyl-receptor-mediated endocytosis provides a sensitive, quantitative, and cell-specific new marker to study their properties and mechanism of action. Extensive, but selective remodeling of m plasma membrane structure could play an important role in controlling recognition and effector mechanisms of the activated m. 相似文献
103.
Perceptions of the Cause,Impact and Management of Persistent Fatigue in Patients with Rheumatoid Arthritis Following Tumour Necrosing Factor Inhibition Therapy 下载免费PDF全文
104.
Acute cocaine administration has been shown to alter dorsal striatal plasticity [Proc Natl Acad Sci USA 87 (1990) 6912; Brain Res Bull 30 (1993) 173] and produce long-term neurochemical changes [Pharmacol Biochem Behav 27 (1987) 533]. To date, the effects of acute cocaine on extracellular glutamate and nerve terminal glutamate immunolabeling in the rat dorsolateral striatum have not been reported. To investigate cocaine-induced changes in extracellular glutamate, in vivo microdialysis was carried out in the dorsolateral striatum of rats 1-14 days after receiving a single injection of either vehicle or 15 mg/kg cocaine. There was an increase in the group injected with cocaine 1 day prior to measuring extracellular glutamate as compared with the control group. The group injected with cocaine 3 days prior to the microdialysis session had decreased extracellular glutamate levels. Furthermore, extracellular glutamate remained attenuated 14 days after acute cocaine treatment. Striatal glutamate decreased in the cocaine-treated rats after calcium removal, suggesting that cocaine-induced changes in extracellular glutamate were partially calcium-dependent. The density of nerve terminal glutamate immunolabeling was measured using immunogold electron microscopy in the contralateral striatum of the same rats that had been acutely treated with cocaine or vehicle. There were no changes in the density of glutamate immunolabeling within identified nerve terminals making an asymmetrical (excitatory) synaptic contact 1, 2, 3, or 14 days after acute cocaine exposure as compared with the control groups. Hence, these alterations in extracellular glutamate did not result from changes in glutamate immunolabeling within the synaptic vesicle pool. In addition, no changes in glutamate immunolabeling were found in rats that received cocaine 2 h previously or were withdrawn after 1 week of cocaine administration. The results demonstrate that a single injection of cocaine produces biphasic, time-dependent changes in extracellular glutamate in the rat dorsolateral striatum. 相似文献
105.
It is hypothesized that anterior cingulate cortex (ACC) function may be disrupted in psychopathy. Since ACC is considered the generator of the error-related negativity (ERN), we expected the ERN to be sensitive to the degree of psychopathy among violent offenders. EEG was collected while offenders and controls responded to a standard letter flanker task and to a face flanker task that required discrimination between angry and fearful expressions. Offenders were as accurate as controls on the letter flanker task but made more errors in emotion discrimination on the face flanker task. ERNs elicited by letter flanker errors did not differ across groups but were markedly reduced in the offenders in the face flanker condition. These effects were related to the degree of psychopathy within the offender group. Source modelling of the ERN also indicated an atypical response for psychopaths when error monitoring required the discrimination of affectively based information. 相似文献
106.
Carel Bron Arthur de Gast Jan Dommerholt Boudewijn Stegenga Michel Wensing Rob AB Oostendorp 《BMC medicine》2011,9(1):8
Background
Shoulder pain is a common musculoskeletal problem that is often chronic or recurrent. Myofascial trigger points (MTrPs) cause shoulder pain and are prevalent in patients with shoulder pain. However, few studies have focused on MTrP therapy. The aim of this study was to assess the effectiveness of multimodal treatment of MTrPs in patients with chronic shoulder pain. 相似文献107.
Apoptosis of thyrocytes and effector cells during induction and resolution of granulomatous experimental autoimmune thyroiditis 总被引:1,自引:0,他引:1
Tang H Chen K Wei Y Sharp GC McKee L Braley-Mullen H 《International immunology》2000,12(12):1629-1639
Experimental autoimmune thyroiditis (EAT) with granulomatous histopathology (G-EAT) can be induced by cells from mouse thyroglobulin (MTg)-immunized donors activated in vitro with MTg and IL-12. G-EAT lesions reach maximum severity 18-21 days after cell transfer and, if some thyroid follicles remain, lesions almost completely resolve by day 35. CD8(+) cells are required for G-EAT resolution. To begin to determine the mechanisms involved in G-EAT resolution, apoptosis in thyroids was analyzed by TUNEL staining. Apoptotic thyrocytes and inflammatory cells were present in the thyroids of both CD8(+) and CD8-depleted recipient mice at day 19-21. By day 35, apoptotic cells were rare in thyroids of mice whose lesions had resolved; the few apoptotic inflammatory cells were generally in close proximity to thyroid follicles. Thyroids of CD8-depleted mice had ongoing inflammation at day 35 and most apoptotic cells were thyroid follicular cells. The expression of Fas and Fas ligand (FasL) mRNA in thyroids was also determined by RT-PCR in both CD8(+) and CD8-depleted recipient mice. Fas was expressed in normal thyroids and its expression was relatively constant throughout the course of disease. FasL mRNA was not expressed in normal thyroids. FasL mRNA expression generally correlated with G-EAT severity, being maximal at day 21 and diminishing as lesions resolved. However, FasL mRNA expression in thyroids of CD8-depleted mice in which resolution was delayed was decreased compared to thyroids of CD8(+) mice with comparable disease severity, suggesting that FasL expressed by CD8(+) cells may play a role in G-EAT resolution. 相似文献
108.
Reka Toth Zsuzsa Pocsai Szilvia Fiatal Gyorgy Szeles Laszlo Kardos Beata Petrovski Martin McKee Roza Adany 《Addiction (Abingdon, England)》2010,105(5):891-896
Background Standardized death rates from chronic liver diseases (CLDs) in Hungary are much higher than the European Union average. Carrying the alcohol dehydrogenase 1B 48His allele (rs1229984 or ADH1B*2) could decrease the risk of alcoholism, but with persistent drinking may confer a greater risk of CLDs. The aim of this study was to assess the prevalence of this polymorphism in the Hungarian population and its association with alcohol consumption and with CLDs. Methods and results A total of 278 cases with diagnosed CLDs and 752 controls without any alterations in liver function, all males aged 45–64, were screened for ADH1B Arg48His polymorphism. ADH1B*2 allele frequencies in controls and cases were 8.31% and 4.50%, respectively (χ2 = 9.2; P = 0.01). Carrying the ADH1B*2 allele was associated with significantly lower odds ratio (OR) for drinking frequency (OR = 0.63; P = 0.003), the number of positive answers on CAGE (Cut‐down, Annoyed, Guilt, Eye‐opener) assessment (OR = 0.58; P = 0.005) and a positive CAGE status (OR = 0.55; P = 0.007). There was a significant association between ADH1B*2 and CLDs (OR = 0.50; P = 0.003), but it disappeared after adjusting for CAGE status and scores (OR = 0.67 P = 0.134; OR = 0.67 P = 0.148, respectively) and weakened after adjusting for drinking frequency (OR = 0.61; P = 0.045). Among heavy drinkers the presence of ADH1B*2 did not increase the risk of cirrhosis but there was a significant interaction between genotype and CAGE status (P = 0.003, P = 0.042), with ADH1B*2 conferring reduced risk of CLDs in CAGE negatives. Conclusion In Hungarians, the ADH1B 48His allele reduces the risk of alcoholism, but not the risk of chronic liver disease among heavy drinkers. 相似文献
109.
Massimo Bongiovanni M.D. Frederic Triponez M.D. Thomas A. McKee M.D. Neeta Kumar M.D. Thomas Matthes M.D. Patrick Meyer M.D. 《Diagnostic cytopathology》2009,37(9):671-675
The diffuse sclerosing variant of papillary thyroid carcinoma (DSV–PTC) is a rare tumor with aggressive behavior that requires aggressive treatment. Despite characteristic clinical and histological features that easily permit diagnosis, pre‐operative fine‐needle aspiration cytology (FNAC) diagnosis is often challenging and thus delays diagnosis. We describe the cytological features of a case of DSV–PTC diagnosed by FNAC in a 30‐year‐old woman presenting with an ill‐defined mass in her neck lasting for 2 months. Ultrasonograpy revealed a heterogeneous enlargement of both thyroid lobes suspicious for a lymphoproliferative syndrome. Flow cytometry showed a suspect B‐lymphocyte population. FNAC showed in five out of six slides an overwhelming presence of slightly atypical monomorphic small lymphocytes. The remaining slide showed syncytial tissue fragments of follicular cells with nuclear enlargement and pleomorphism, irregular nuclear membrane, grooves with scattered intranuclear inclusions, squamous metaplastic epithelium, and abundant psammoma bodies. A diagnosis of DSV–PTC was rendered and confirmed by total thyroidectomy and lymph node dissection. Our report supports the possibility of obtaining a preoperative diagnosis of DSV–PTC by FNAC. In the case of diffuse thyroid enlargement, adequate sampling of the thyroid and the presence of the combination of features described in our case permitted the diagnosis of this PTC variant. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc. 相似文献
110.
Keith R. Spencer Zachariah W. Foster Nazifa Abdul Rauf Latease Guilderson Derek Collins James G. Averill Sean E. Walker Ian Robey Jonathan D. Cherry Victor E. Alvarez Bertrand R. Huber Ann C. McKee Neil W. Kowall Christopher B. Brady Thor D. Stein 《Brain pathology (Zurich, Switzerland)》2020,30(6):1028
Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder affecting both the upper and lower motor neurons. Although ALS typically leads to death within 3 to 5 years after initial symptom onset, approximately 10% of patients with ALS live more than 10 years after symptom onset. We set out to determine similarities and differences in clinical presentation and neuropathology in persons with ALS with long vs. those with standard duration. Participants were United States military Veterans with a pathologically confirmed diagnosis of ALS (n = 179), dichotomized into standard duration (<10 years) and long‐duration (≥10 years). The ALS Functional Rating Scale‐Revised (ALSFRS‐R) was administered at study entry and semi‐annually thereafter until death. Microglial density was determined in a subset of participants. long‐duration ALS occurred in 76 participants (42%) with a mean disease duration of 16.3 years (min/max = 10.1/42.2). Participants with long‐duration ALS were younger at disease onset (P = 0.002), had a slower initial ALS symptom progression on the ALSFRS‐R (P < 0.001) and took longer to diagnose (P < 0.002) than standard duration ALS. Pathologically, long‐duration ALS was associated with less frequent TDP‐43 pathology (P < 0.001). Upper motor neuron degeneration was similar; however, long‐duration ALS participants had less severe lower motor neuron degeneration at death (P < 0.001). In addition, the density of microglia was decreased in the corticospinal tract (P = 0.017) and spinal cord anterior horn (P = 0.009) in long‐duration ALS. Notably, many neuropathological markers of ALS were similar between the standard and long‐duration groups and there was no difference in the frequency of known ALS genetic mutations. These findings suggest that the lower motor neuron system is relatively spared in long‐duration ALS and that pathological progression is likely slowed by as yet unknown genetic and environmental modifiers. 相似文献