老年牙周炎牙龈组织诱导型一氧化氮合酶分布研究

目的 :观察慢性老年牙周炎患者牙龈组织中诱导型一氧化氮合酶 (iNOS)分布。方法 :采用免疫组织化学方法对 10例慢性老年牙周炎患者、10例慢性成人牙周炎患者、10例青少年牙周炎患者和 10例健康老年人牙龈组织中诱导型一氧化氮合酶分布进行了检测并比较研究。结果 :(1)牙周炎时牙龈组织中诱导型一氧化氮合酶主要在鳞状上皮细胞胞浆核周区颗粒状阳性表达 ,毛细血管壁内皮细胞、老化的胶原纤维及上皮下基底膜共同形成了一种乳头状轮廓样阳性表达形态 ,结缔组织和肉芽组织中各类炎症细胞也显阳性表达 ;(2 )慢性老年牙周炎组血管壁内皮细胞、结缔组织内炎症细胞、上皮乳头阳性表达例数明显低于青少年牙周炎组和慢性成人牙周炎组 (P <0 .0 5 )。血管壁内皮细胞和胶原纤维阳性表达例数低于健康老年人组 (P <0 .0 5 )。结论 :慢性老年牙周炎患者牙龈组织中诱导型一氧化氮合酶的表达明显降低 ,造成了局部一氧化氮(NO)合成减少 ,引起了局部牙龈组织免疫功能降低和免疫调节功能紊乱     

诱导型一氧化氮合酶在颌骨肉瘤中的表达及意义

目的：研究诱导型一氧化氮合酶（iNOS）在颁骨肉瘤中的表达情况及其和肿瘤血管形成、临床病理特征之间的关系。方法：应用S-P免疫组织化学法检测iNOS和CDB4在颌骨肉瘤中的表达。结果：颌骨肉瘤中存在iNOS的过度表达;iNOS表达与微血管密度有关;iNOS表达与颌骨肉瘤大小、病理分级、临床分期、初／复发等临床病理特征有关,与肿瘤的转移无关。结论：iNOS有促进颌骨肉瘤中肿瘤血管形成的作用,iNOS是肿瘤治疗的一个重要靶点。     

Expression of inducible nitric oxide synthase and p53 in oral epithelial dysplasia

AIM: Nitric oxide (NO) has been studied in a variety of human cancers and is implicated in both tumor promotion and inhibition. Downregulation of the enzyme iNOS by wild-type p53 (but not mutant) protein has been shown to occur in normal cells and some tumors, but the relationship has not been reported in oral epithelial dysplasia. METHODS AND RESULTS: An immunohistochemical study was conducted with antibodies to iNOS and p53 (clone DO-7) in 36 cases of oral dysplasia of varying severity. Statistical analysis showed a significant correlation between iNOS staining and grade of dysplasia (P <.001) and between p53 and iNOS staining (P <.001). CONCLUSIONS: This preliminary study has shown that iNOS expression correlates with severity of dysplasia, and it is also increased in those cases showing positive staining for p53. Further research is required to fully establish the relationship between iNOS and p53 in both dysplasia and oral squamous cell carcinoma.     

诱导型一氧化氮合酶和血管内皮生长因子在成釉细胞瘤中的表达

目的：研究诱导型一氧化氮合酶（iNOS）和血管内皮生长因子（VEGF）在成釉细胞瘤（AB）中表达的相关性，探讨两者与成釉细胞瘤血管生成和临床生物学行为的关系。方法：应用免疫组化SP法。检测35例良性成釉细胞瘤（原发24例、复发11例）及5例恶性成釉细胞瘤和10例牙源性角化囊性瘤（KCOT）中VEGF、iNOS的表达和微血管密度（MVD）（CD34标记）。并对上述指标用SPSS11．0统计软件包进行统计学分析。结果：KCOT、原发AB、复发AB、恶性AB中的iNOS、VEGF的阳性表达率和MVD计数依次增加，组间差异均具有统计学意义（P〈0．05）；MVD在成釉细胞瘤中计数均随着iNOS和VEGF表达的增强而升高（P〈0．05）；iNOS和VEGF两者在成釉细胞瘤之间也具有相关性（rs=0．66，P〈0．05）。结论：iNOS和VEGF的表达与成釉细胞瘤的血管生成及其侵袭性生物学行为密切相关。     

Expression and pathological relevance of inducible nitric oxide synthase in osteosarcoma of the jaws

The aim of the present study was to examine the expression of inducible nitric oxide synthase (iNOS) in osteosarcoma of the jaw, and its relationship with tumour angiogenesis and clinicopathological characteristics. Streptavidin peroxidase immunohistochemical staining was used to detect the expression level of iNOS and CD34 in paraffin-embedded samples from 25 patients. Osteosarcoma of the jaw was associated with overexpression of iNOS, which correlated with tumour microvessel density (MVD). iNOS expression correlated with the size, pathological grade and clinical stage of the osteosarcoma, and also with clinicopathological characteristics such as primary occurrence or recurrence of tumours. There was no correlation with metastasis. iNOS may promote tumour angiogenesis in osteosarcoma of the jaw, and so may represent an important target in anti-tumour therapy.     

大鼠正畸牙移动中牙髓iNOS表达的免疫组化研究

目的:建立大鼠正畸牙移动模型,观察牙髓组织中诱导型一氧化氮合酶(iNOS)的表达及分布,探讨正畸牙移动过程中牙髓改建的分子机制。方法:采用免疫组织化学方法对正畸加力后12h、1d、3d、7d和14d大鼠牙髓组织中iNOS进行检测,观察iNOS的时空分布。结果:iNOS阳性反应的产物呈深褐色均质沉淀,主要在血管内皮细胞、成牙本质细胞胞浆核周区颗粒状阳性表达。这种染色在正畸加力后12h、1d、3d天有不同程度的增强,3d达到高峰,加力后7d和14d表达减弱,第14d与对照组无明显差异。结论:正畸牙移动过程中牙髓组织iNOS的表达先升高后逐渐恢复正常,提示iNOS可能在正畸牙移动牙髓组织改建过程中起重要作用。     

Expression of inducible nitric oxide synthase and heat shock proteins in periapical inflammatory lesions

BACKGROUND: The mechanisms responsible for activation and proliferation of lining epithelium involved in inflammatory processes in periapical inflammatory lesions remain unclear. In this study, the expression and distribution of inducible nitric oxide synthase (iNOS) and heat shock proteins (HSPs) were immunohistochemically investigated in periapical inflammatory lesions. METHODS: Control specimens of periodontal ligaments including Malassez epithelial rests from seven teeth and periapical inflammatory lesions (15 apical granulomas (AGs), 16 radicular cysts (RCs), and 10 residual radicular cysts (RRCs)) were prepared and examined by the standard streptavidin-biotin peroxidase complex method using anti-iNOS rabbit polyclonal antiserum, and anti-HSP27, -HSP60, -HSP70 mouse monoclonal antibodies. RESULTS: Immunoreactivity for iNOS was detected in macrophages, lymphocytes, and endothelial cells of granulation tissue and in lining epithelium of periapical inflammatory lesions. Malassez epithelial rests showed no or slight staining for iNOS. The epithelial staining intensity of iNOS in RCs was greater than that in Malassez epithelial rests and RRCs. Immunoreactivity for HSP27 was recognized in inflammatory cells, endothelial cells and lining epithelium of periapical inflammatory lesions and in Malassez epithelial rests. HSP60 was detected in some lymphocytes of granulation tissue and in lining epithelium of periapical inflammatory lesions, whereas Malassez epithelial rests showed no staining for HSP60. Epithelial HSP60 reactivity was more intense in RCs than in RRCs. HSP70 was expressed in lymphocytes, endothelial cells and lining epithelium of periapical inflammatory lesions and in Malassez epithelial rests. The staining intensity of HSP70 in Malassez epithelial rests was slightly lower than that in lining epithelium of RCs and RRCs. CONCLUSIONS: These data demonstrate that the expressions of iNOS, HSP60, and HSP70 are involved in inflammatory processes and might play a role in the activation and proliferation of lining epithelium, leading to progression of periapical inflammatory lesions.     

Expression of inducible nitric oxide synthase in cutaneous adnexal tumours of the head and neck

Adnexal tumours are a rare heterogeneous group of neoplasms, most commonly found in the head and neck region. Although most are benign, malignant adnexal tumours often behave aggressively, resulting in early metastasis. There is increasing interest in the role that nitric oxide (NO) plays in the behaviour of many cancers. It is thought that NO, produced by the enzyme inducible NO synthase (iNOS), facilitates tumour growth and dissemination. iNOS has been studied in the common skin cancers, where its expression correlates with tumour behaviour, but it has not been previously investigated in cutaneous adnexal tumours. An immunhistochemical study was performed using a monoclonal antibody to iNOS in 37 cases of adnexal tumours (19 benign, 18 malignant). iNOS expression was weakly expressed by basal keratinocytes of adjacent skin in all cases and it was variably expressed in the tumours. Malignant tumours had significantly increased iNOS expression when compared to both adjacent skin (P<0.001) and the benign tumour group (P<0.001). No significant difference was found between iNOS expression in benign tumour and adjacent skin (P=0.5). The role of iNOS in this rare group of tumours and the possibility of pharmacologically inhibiting it in the clinical setting warrants further investigation.     

Human gingival fibroblasts produce nitric oxide in response to proinflammatory cytokines

BACKGROUND: Although nitric oxide (NO) synthesis is increased in periodontal disease (PD), little is known about the possible sources of production by gingival tissues. In fact, gingival tissues from patients with periodontitis demonstrate greater levels of inducible nitric oxide (iNOS) expression than healthy tissue. Macrophages are the source of the iNOS expression, with endothelial cells also contributing. In the present study, our hypothesis has been that human gingival fibroblasts (HGF) also have the ability to produce NO. We have established for the first time that HGF express increased levels of iNOS and modulate NO synthesis in response to proinflammatory cytokines that act synergistically. METHODS: NO production under basal conditions or following incubation with tumor necrosis factor (TNF-alpha), interleukin (IL)-1beta, and interferon (IFN)-gamma was assessed by measurement of stable NO metabolites, nitrite, and nitrate, in a microplate adaptation of the Griess assay. Total RNA was isolated from HGF for determination of iNOS mRNA levels. RESULTS: We have shown that NO production is elevated in HGF that are stimulated simultaneously by TNF-alpha, IL-1beta, and IFN-gamma. Northern blot analysis confirmed that the production of iNOS mRNA by HGF is upregulated in the presence of these cytokines. Addition of mercaptoethyl guanidine (MEG), a specific inhibitor of iNOS, profoundly reduced the production of NO in HGF. Non specific inhibitors of iNOS, L-NG-monomethyl arginine (L-NMMA), and L-arginine-methyl ester (L-NAME) had little or no effect on NO produced in HGF. CONCLUSIONS: These results suggest that elevated NO production could be important in the pathogenesis of PD, and also suggest the ability of an iNOS inhibitor to modulate the disease. Treatments with drugs to block the production of nitric oxide or block its effects might be therapeutically valuable.     

Immunohistochemical localization of inducible nitric oxide synthase in synovial tissue of human temporomandibular joints with internal derangement

The expression and distribution of inducible nitric oxide synthase (iNOS) was examined in 12 samples of human temporomandibular joint (TMJ) with internal derangement (ID) and four control specimens. In the diseased joints, strong or definite iNOS reactivity was expressed in synovial lining and endothelial cells; weaker activity was present in synovial fibroblasts. In contrast, although there was weak expression of iNOS in synovial fibroblasts and endothelial cells in the two control specimens, there was no iNOS staining in the synovial lining cell layers. This original report that iNOS is expressed in the synovial tissue of the temporomandibular joint indicates that nitric oxide is produced locally at least in the synovial lining in these joints when affected by internal derangement.     

口腔癌中诱导型一氧化氮合酶与血管内皮生长因子表达关系的研究

目的研究诱导型一氧化氮合酶(inducible nitric oxide synthase,iNOS)在口腔癌中表达水平以及与口腔癌血管内皮生长因子(vascular endothelial growth factor,VEGF)表达和淋巴结转移的关系.方法以正常口腔粘膜作对照,采用免疫组化SP法检测41例口腔癌组织中iNOS的表达,同时检测口腔癌中VEGF的表达和微血管密度(MVD)(CD34标记).结果口腔癌组织iNOS阳性表达率为63.41%,淋巴结阴性组和阳性组差异有显著性(P<0.01),而9例正常口腔粘膜表达均为阴性;在iNOS不同表达组间MVD值差异有高度显著性(P<0.001),VEGF的表达差异有显著性(P<0.05).结论 iNOS在口腔癌中高表达,并与肿瘤血管形成、淋巴结转移密切相关;它可能参与VEGF促血管生成作用.     

Nitric oxide synthase type-II is synthesized by human gingival tissue and cultured human gingival fibroblasts

Nitric oxide is known to be an important inflammatory mediator, and is implicated in the pathophysiology of a range of inflammatory disorders. The aim of this study was to determine the localization and distribution of endothelial NOS (NOS-II) in human gingival tissue, and to ascertain if human gingival fibroblasts express NOS-II when stimulated with interferon gamma (IFN-gamma) and bacterial lipopolysaccharide (LPS). The distribution of NOS-II in inflamed and non-inflamed specimens of human gingivae was studied using a monoclonal antibody against nitric oxide synthase II. Cultures of fibroblasts derived from healthy human gingivae were used for the cell culture experiments. The results from immunohistochemical staining of the tissues indicated an upregulation of NOS-II expression in inflamed compared to non-inflamed gingival tissue. Fibroblasts and inflammatory cells within the inflamed connective tissue were positively stained for NOS-II. In addition, basal keratinocytes also stained strongly for NOS-II, in both healthy and inflamed tissue sections. When cultured human gingival fibroblasts were stimulated by INF-gamma and Porphyromonas gingivalis LPS, NOS-II was more strongly expressed than when the cells were exposed to LPS or IFN-gamma alone. These data suggest that, as for other inflammatory diseases, NO plays a role in the pathophysiology of periodontitis.     

A study to assess inducible nitric oxide synthase expression in oral lichen planus

Nitric oxide (NO) has been implicated in a variety of diseases but has not been previously studied in oral lichen planus (OLP). Since OLP has a complex immunogenesis with abundant macrophage infiltration, this study determined by immunohistochemistry whether or not the expression of the inducible form of nitric oxide synthase (iNOS) was increased in this condition relative to normal mucosa. Thirty cases of OLP and 10 normal buccal mucosa biopsies were studied utilising primary antibodies to iNOS and CD68, a myelomonocytic marker. iNOS activity was additionally assessed using a [(14-)C]-labelled arginine to citrulline assay. CD68 expression was significantly increased in the cellular infiltrate of all 30 cases of OLP compared with normal mucosa (P<0.009). Although iNOS staining was seen in a minority of cells in nine cases, this was not statistically significant when compared with the absent staining in normal oral mucosa (P=0.26). Furthermore, the minimal iNOS activity found in OLP was similar to that in normal mucosa. We conclude that expression of iNOS by macrophages is downregulated in OLP and discuss the possible reasons for this finding.     

诱导型一氧化氮合酶与牙源性颌骨囊肿骨吸收的关系

目的探讨牙源性颌骨囊肿骨吸收的机制。方法采用免疫组化SP法检测55例牙源性颌骨囊肿石蜡切片中诱导型一氧化氮合酶(induciblenitricoxidesynthase,iNOS)的表达(以10例正常口腔粘膜作对照)。囊肿体积采用骨腔注水法测定。结果牙源性颌骨囊肿上皮细胞iNOS阳性表达的病例28例,占50.91%,10例正常口腔粘膜iNOS表达均为阴性。在iNOS表达(-)~()各组中囊肿体积(ml)分别为2.08±1.92、4.71±5.55、3.16±2.98、1.18±1.36,(-)与(+)、()及(+)~()组间差异有显著性(P<0.05)。根尖囊肿、始基囊肿、角化囊肿iNOS表达无显著性差异(P>0.05)。结论在骨吸收机理中iNOS起着重要作用,其表达水平与颌骨囊肿骨吸收具有正相关。