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101.
García-González M Abdulkader I Boquete AV Neo XM Forteza J Cameselle-Teijeiro J 《Virchows Archiv : an international journal of pathology》2005,447(1):12-17
This study was undertaken to investigate cyclooxygenase-2 (COX-2) expression in follicular cells of the human thyroid. COX-2 expression was studied immunohistochemically in a total of 174 samples. COX-2 immunoreactivity was confined to the cell cytoplasm with the nuclei remaining unlabelled. COX-2 expression was observed in five cases (17.2%) of normal follicular cells and in one case (16.6%) of solid cell nests. Follicular carcinoma expressed COX-2 more frequently than follicular adenoma (93.4% vs 21.1%) (p0.001). A higher percentage of cases of papillary microcarcinomas up-regulated COX-2 in comparison with all papillary carcinomas (p0.05). However, we could not establish any relationships among COX-2, patients ages or lymph node metastases in papillary carcinomas. COX-2 expression was found in 12 (92.3%) poorly differentiated carcinomas and in 13 (92.8%) undifferentiated carcinomas. We found that COX-2 is not always useful as a marker of malignancy. Our results suggest that COX-2 plays a role in progression of all thyroid carcinomas, but in papillary carcinomas, seems more important only in the early stages. COX-2 expression in the undifferentiated carcinoma deserves special consideration due to its prognosis and to the fact that selective COX-2 inhibitors were found to enhance tumour response to radiation in some studies. 相似文献
102.
Transient expression of osteopontin mRNA and protein in amoeboid microglia in developing rat brain 总被引:3,自引:0,他引:3
Choi JS Cha JH Park HJ Chung JW Chun MH Lee MY 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2004,154(3):275-280
To investigate a potential role of osteopontin (OPN) in developing rat brain, the expression of OPN mRNA and protein in the developing rat brain relative to the distribution of brain macrophages was investigated using in situ hybridization and immunohistochemistry, and the phagocytic capability of OPN-expressing cells was accessed using rhodamine isothiocyanate (RhIc) as a tracer. OPN-expressing cells appeared from embryonic day 16. During the first week of postnatal life, OPN-labeled cells increased markedly, and peaked around P7, then declined and had completely disappeared by the end of the second postnatal week. The spatiotemporal distribution pattern of OPN mRNA closely matched that of OPN protein. Their morphology and localization were compared with those of cells expressing the established microglial marker OX-42 in adjacent sections, and double-labeling studies demonstrated that OPN was localized to the amoeboid microglia which stain with the lectin GSI-B4, another marker for microglia. Furthermore, OPN-labeled cells were confirmed to be active phagocytes emitting RhIc fluorescence indicating that the tracer into the brain tissues was engulfed by phagocytosis. Therefore, these results provide the first evidence that OPN is transiently expressed in active brain macrophages in the embryonic and early postnatal brain, and suggest that OPN may contribute to the migration and phagocytic function of brain macrophages in the developing brain.This work was supported by a Korea Research Foundation grant (KRF-2002-015-EP0106) 相似文献
103.
Kawakubo Y Kishimoto H Sato Y Yanagimoto K Tsuruta T Ogawa Y Kameya T 《Virchows Archiv : an international journal of pathology》1999,434(2):109-115
Langerhans cell histiocytosis (LCH) has been thought to be a disorder of immune regulation, and increasingly, evidence showing
that the tissue damage in LCH involves lymphokines and pro-inflammatory cytokines is reported. We detected human cytomegalovirus
(HCMV)-DNA in LCH cells in the foci of LCH lesions by immunohistochemistry, in situ hybridization and PCR. HCMV was detected
in the nuclei and/or cytoplasm of LCH cells in 9 of 27 LCH cases by immunostaining. HCMV was probably an early antigen. In
situ hybridization revealed signals for HCMV-DNA only in the nuclei of LCH cells in 10 of the 27 LCH cases. PCR analysis was
performed in 20 of the LCH cases, and HCMV-DNA was detected in 7 of these. All 7 positive cases were also positive for HCMV
by ISH and IHC. These findings suggested that early phase infection or reactivation of HCMV occurred in the LCH lesions. HCMV
infection may be accompanied by impaired cytokine production. Our study also suggested a relationship between HCMV infection
and expression of TNFα. In tissues affected by LCH, dermatopathic lymphadenopathy or malignant fibrous histiocytoma and in
normal tissues no signals for Epstein-Barr virus-RNA were detected. These findings suggest that in some cases LCH is associated
with HCMV infection.
Received: 24 November 1998 / Accepted: 24 April 1998 相似文献
104.
Li Zhihai Gao Qixue Tao Baohong Lv Jingyao Cai Zhiyi 《Anatomical record (Hoboken, N.J. : 2007)》2008,291(12):1662-1672
Decompression operation of the optic canal via the nasal path under endoscope is widely used, but it is both a challenging and controversial method. Unsatisfactory results were largely associated with otolaryngologists' limited understanding of the real anatomical situations of the optic canal before operation. To provide otolaryngologists with the real situations and data preoperation, multislice helical CT was used to reconstruct the images of the optic canal. Using multislice helical CT‐aided three‐dimensional reconstructive methods in combination with direct anatomic measurement, we dissected and analyzed the shape of the optic canal and its anatomic relationship with the adjoining structures in 40 intact postmortem skull samples. The In‐Space technique clearly showed the structure and the related region of the optic canal. The virtual endoscopy technique showed superbly the spatial appearance and topography of the inner optic canal and also gave the inner structure of the optic canal optically. There was no statistic difference in three‐dimensional reconstructive data with that obtained by anatomical measurements and thus can be used to directly instruct the clinic operation. These results demonstrate that a combined In‐Space technique with virtual endoscopy can accurately define the subtle structure and the related region of the optical canal. In conclusion, multislice helical CT‐based three‐dimensional reconstruction is of important value for clinical operations. Anat Rec, 2008. © 2008 Wiley‐Liss, Inc. 相似文献
105.
Infants with Ureaplasma urealyticum in the lower respiratory tract are at risk for chronic lung disease (CLD) or bronchopulmonary dysplasia (BPD) but causality has been difficult to prove. The goal of this study was to identify ureaplasma in human neonatal lung tissue using the in situ hybridization (ISH) procedure described in Part 1 (Exp. Mol. Pathol., in press) of this report. By correlating their presence with the histopathologic findings, it may be possible to provide further evidence of the pathogenicity of ureaplasmas and their association with BPD. Lung autopsy tissue from seven infants with positive cultures and seven infants with negative cultures for ureaplasma were included in the study. All culture-positive infants were positive for ureaplasma on ISH and all had histopathologic evidence of BPD. Two of the seven infants with negative cultures were positive for ureaplasma with ISH. Of interest, these two infants were also found to have BPD at autopsy. The other five infants with negative cultures were also negative for ureaplasma on ISH and had no evidence of BPD. This study correlates the presence of U. urealyticum by ISH with the finding of BPD on histopathologic evaluation and provides evidence that it has a role in the development of CLD. 相似文献
106.
以乙肝疫苗、人喉癌细胞膜抗原为抗原,猪脾细胞为效应细胞,经体外免疫后收集应答细胞,制备PSHBV-TF PSAC-iRNA。通过抗原特异性细胞免疫功能试验证实,PSHBV-TF和PSAC-iRNA都能转移特异性细胞免疫功能。采用体外免疫法制备PSHBV-TF和PSAC-iRNA是可行的,并且具有诸多优点。 相似文献
107.
马桑内酯致痫后大鼠海马生长抑素mRNA表达的变化 总被引:2,自引:0,他引:2
为探讨马桑内酯致痫与生长抑素的关系,用原位杂交组织化学法研究了马桑内酯致痫后大鼠海马生长抑素mRNA阳性神经元的变化,结果表明:致痫组大鼠CA1,CA2区及齿状回生长抑素mRNA的反应明显增强,以上各区的中,小神经内生长抑素mRNA神经元的数目及强度明显高于正常对照组,两者有显著性差异。 相似文献
108.
Ch. Breier A. Dzien H. -J. Lisch H. Braunsteiner 《Journal of molecular medicine (Berlin, Germany)》1984,62(12):593-594
Summary Diseases associated with acidotic blood-pH, such as chronic renal disease, diabetes mellitus or chronic alcoholism, show a marked impairment of lipoprotein lipase. Therefore we influenced blood-pH in 3 healthy subjects by infusions to get alkalotic, neutral and acidotic blood-pH on three days in series. On each day blood-pH from capillary blood and post-heparin lipoprotein lipase from fasting plasma was determined. In comparison to neutral blood-pH in vivo, alkalosis did not influence lipoprotein lipase. In contrast, during artificial acidosis, lipoprotein lipase was impaired significantly (p<0.01). Therefore, it seems, that acidosis inhibits lipoprotein lipase in vivo. 相似文献
109.
Kotaro Kaneko Paul H. Guth Jonathan D. Kaunitz 《Pflügers Archiv : European journal of physiology》1992,421(4):322-328
Intracellular pH (pHi) and viability of gastric surface cells of the rat stomach in response to luminal acidification, and the role of Na+/H+ exchange in maintaining pHi homeostasis were studied in vivo using a fluorescent microscopic technique. pHi was measured during superfusion with buffers of pH 1.2–7.4. When the pH of the superfusate was 7.4, baseline pHi was unchanged. Superfusion with pH 3 buffer rapidly decreased pHi to 6.7, with subsequent recovery to baseline pHi within 15 min despite continuing acid exposure. Superfusion with buffers of pH 1.7 and 1.2 decreased pHi continuously to below 6.2 with no recovery observed. Despite the relentless decline in pHi during superfusion with pH-1.2 and –1.7 solutions, over 75% of the surface cells were still viable, as measured by exclusion of the vital dye propidium iodide. We then examined the role of Na+/H+ exchange in the regulation of pHi. Superfusion with amiloride did not affect recovery of pHi from intracellular acidification induced by a NH4Cl prepulse. Exposure to the potent, lipophilic Na+/H+ exchange inhibitor 5-(N,N-hexaniethylene)-amiloride (HMA), either in the superfusate or by close arterial perfusion, decreased baseline pHi from 7.1 to 6.8. Close arterial perfusion of HMA additionally attenuated the recovery of pHi to baseline during superfusion with pH 3 buffer. We conclude that luminal protons permeate into the cytoplasm of gastric surface cells, where they are eliminated by an Na+/H+ exchanger, most probably localized to the basolateral membrane. 相似文献
110.
Anti-inflammatory activity of phosphodiesterase (PDE)-IV inhibitors in acute and chronic models of inflammation 下载免费PDF全文
L. SEKUT D. YARNALL S. A. STIMPSON L. S. NOEL R. BATEMAN-FITE R. L. CLARK M. F. BRACKEEN J. A. MENIUS K. M. CONNOLLY 《Clinical and experimental immunology》1995,100(1):126-132
Inhibitors of cyclic nucleotide phosphodiesterases are known to suppress lipopolysaccharide (LPS)-induced tumour necrosis factor-alpha (TNF-α) production in vitro in human monocytes. The most potent of these have selectivity for type IV PDEs, suggesting that this class of PDE is the major type involved in the regulation of human TNF-α production. Using compounds of two distinct chemical structural classes, a quinazolinedione (CP-77 059) and a 4 arylpyrrolidinone (rolipram). we show here that PDE-IV-specific inhibitors are also potent in suppressing LPS-induced TNF-α production in vitro in sodium periodate-elicited murine macrophages (IC50s of 1 and 33, respectively). We then report the in vivo anti-inflammatory effect of PDE-IV inhibition in five murine models of inflammation: (i) elevation of serum TNF-α induced by a subtethal LPS injection; (ii) LPS-induced endotoxic shock; (iii) LPS/galactosamine-induced endotoxic shock; (iv) carrageenan-induced paw oedema; and (v) adjuvant arthritis. Following a sublethal (5 μg/mouse) injection of LPS, serum TNF-α levels in mice peaked sharply, reaching concentrations of 3–12 ng/ ml 90 min after injection. In this sublethal LPS assay, CP-77 059 was about 30 times more potent than rolipram, with a minimum effective dose of 0.1 mg/kg versus 3 mg/kg for rolipram. This rank order is in keeping with the relative in vitro IC50S for CP-77059 and rolipram, as well as their relative Ki against the human PDE-IV enzyme (46 nM and 220 nM, respectively). In LPS-induced endotoxic shock, rolipram and CP-77 059 at relatively high doses of 30 and 10 mg/kg, respectively, significantly reduced serum TNF-α levels, and also inhibited mortality 66%. In the LPS/galactosamine shock model, in which mice are rendered exquisitely sensitive to LPS by co-injection with galactosamine, only 0.1 μg of LPS/mouse Is necessary for serum TNF-α elevation and death. Both rolipram and the CP-77059 caused dose-dependent reduction of serum TNF-α and lethality. In the carrageenan-induced paw oedema model, in which there is a pronounced local TNF-α response (without a serum TNF-α elevation), rolipram significantly inhibited paw swelling as well as localized TNF-α levels in the paw. In the adjuvant arthritis model, a chronic model of inflammation also possessing localized TNF-α elevation in the inflamed paw, rolipram and CP-77059 suppressed ankle swelling and radiological evidence of joint damage. These data are consistent with a major role for PDE-IV in regulation of TNF-α production and inflammatory responses in murine systems. It suggests a potential therapeutic use for PDE-IV-specific inhibitors in inflammatory disease such as rheumatoid arthritis, septic shock and other inflammatory diseases where TNF-α has been postulated to be a contributing factor in the pathology of the disease. 相似文献