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31.
Cholestatic liver diseases are rare diseases that often lead to cirrhosis and its consequent complications. In addition to liver-related morbidity, patients with cholestatic liver diseases often suffer from autoimmune diseases that affect several organs and tissues. The robust and efficient data collection and collaboration between hepatologists and rheumatologists have led to significant advancements in understanding the relationship between the cholestatic liver diseases and associated autoimmune diseases. In this paper, we discuss the cholestatic liver diseases (primary biliary cirrhosis, primary sclerosing cholangitis and immunoglobulin G4 associated cholangitis) and associated autoimmune diseases.  相似文献   
32.
The term “IgG4-related disease” encompasses several disorders described many years ago under various designations depending on the organ or system involved (e.g., Mikulicz syndrome, Riedel's thyroiditis, and retroperitoneal fibrosis). The clinical presentation varies widely, as one or more organs may be affected, usually in the same region of the body and either synchronously or metachronously. The main targets are the pancreas, bile ducts, salivary glands, lachrymal glands, mediastinal lymph nodes, and retroperitoneum. IgG4-related disease is rare, with an estimated incidence of 0.2 to 1/100 000 in Japan and no available incidence data in occidental countries. Men older than 50 years are predominantly affected. Serum IgG4 levels are often greater than 1.35 g/L. Enlargement of the involved organs, which may be pseudotumoral, is due to a combination of infiltration by T cells and IgG4-expressing plasma cells, storiform fibrosis, and obliterative thrombophlebitis. Glucocorticoid therapy is effective but may be followed by relapses requiring the use of immunomodulating agents such as azathioprine, methotrexate and, more recently, rituximab. IgG4-related disease is not an autoimmune condition related to IgG4 autoantibodies, and neither does it involve immune complexes. Specific joint involvement has been reported in a very small number of patients.  相似文献   
33.
目的 总结和分析IgG4相关性疾病(IgG4-RD)泌尿系统损害的临床特点.方法 收集24例IgG4相关性疾病泌尿系统损害患者的临床资料,回顾性分析患者肾脏受累、治疗前后Scr、Hb、炎性反应指标和IgG4亚类水平的变化情况.结果 2010年8月至2014年5月经北京协和医学院肾内科确诊的IgG4相关性疾病泌尿系统损害病例24例,平均受累器官数目(4.38±1.55)个.治疗前血清IgG4[M(范围)]为12 750(1 460~ 59 400) mg/L,均伴炎性反应指标明显升高.20例患者有检测尿蛋白量,其中19例尿蛋白量升高,6例伴肾病综合征.21例患者Scr升高,均值为(410.48±352.17) μmol/L,其中3例需接受透析治疗.14例患者伴贫血,8例伴单侧或双侧肾脏体积缩小.21例Scr升高的患者中,11例患者肾功能不全因肾后性梗阻所致,3例病理证实为肾小管间质肾炎.与治疗前相比,24例患者糖皮质激素联合或不联合免疫抑制剂治疗1周后Scr明显下降(P<0.05),治疗1个月后Scr下降更为明显(P<0.01),3例透析患者均脱离透析.血沉于治疗1个月后亦明显下降(P<0.01).IgG4亚类水平在治疗1个月时无显著下降(P>0.05),治疗2个月时明显下降(P<0.01).结论 IgG4相关疾病合并肾功能不全并不少见,对中至大量糖皮质激素治疗反应良好,治疗后Scr下降早于血沉和IgG4亚类.  相似文献   
34.
Objective To discuss the relationship between serum anti-Phosphalipase A2 receptor (PLA2R) antibodies and glomerular IgG4 subclass in patients with membranous nephropathy and evaluate the diagnostic value of the two markers. Methods Patients diagnosed as membranous nephropathy from October 2011 to April 2014 in Peking Union Medical College Hospital were included and divided into IMN and SMN groups accoding to their clinical diagnosis. Serum anti-PLA2R antibodies and glomerular IgG subclasses were both detected by indirect immunofluorescence assay. Receiver operator characteristic curves were used to evaluate the diagnostic efficiency of anti-PLA2R antibodies and glomerular IgG4. Results Prevalence of serum anti-PLA2R antibodies of IMN patients was 69.5% (41/59); prevalence of MLN patients was 4.8% (1/21). Within the IMN group, thirty-five patients showed positive results of both serum anti-PLA2R antibodies and glomerular IgG4; Six patients were positive for serum anti-PLA2R antibodies but negative for glomerular IgG4; Seventeen patients were positive for glomerular IgG4 but negative for serum anti-PLA2R antibodies; one patient was negative for both tests. The sensitivity of serum anti-PLA2R antibody was 69.5% and the specificity was 95.2%; the sensitivity of glomerular IgG4 was 89.8% and the specificity was 52.3%. The sensitivity of the combined marker consisting of serum anti-PLA2R antibody and glomerular IgG4 was 59.3% and the specificity was 100%. Four out of the six patients secondary to HBV infection, one out of the three patients secondary to Sjögren syndrome, one out of the three patients secondary to malignant tumor showed positive results of serum anti-PLA2R antibodies. Conclusions Serum anti-PLA2R antibodies were of high prevalence among IMN patients; the prevalence among SMN patients varied with etiologies. Results of serum anti-PLA2R antibodies and glomerular IgG4 were helpful to rule out secondary etiologies in the diagnosis of membrnous nephropathy.  相似文献   
35.
AIM: The purpose of this study was to characterize serum antibody responses to different serotypes of Actinobacillus actinomycetemcomitans strains in various forms of periodontitis and to determine whether any specific type of A. actinomycetemcomitans was associated with any specific form of periodontitis in a Japanese population. METHODS: Sonicated whole cell and autoclaved serotype antigens of A. actinomycetemcomitans were used. Serum IgG titer and avidity to A. actinomycetemcomitans were measured by enzyme-linked immunoabsorbant assay (ELISA) and ammonium thiocyanate-dissociation ELISA, respectively, in 46 aggressive periodontitis patients (8 localized, 38 generalized), 28 chronic periodontitis patients, and 18 periodontally healthy subjects. The presence of A. actinomycetemcomitans in plaque and saliva samples was determined using polymerase chain reaction. RESULTS: Generalized aggressive and chronic periodontitis patients exhibited significantly higher IgG titers than healthy subjects to both sonicated and autoclaved antigens of serotype c strains, while IgG titer to serotype b (Y4) was significantly higher in localized aggressive periodontitis patients compared to healthy subjects. No A. actinomycetemcomitans was detected in localized aggressive periodontitis patients. A. actinomycetemcomitans-positive patients exhibited significantly higher IgG titer and avidity to serotype c than A. actinomycetemcomitans-negative patients. In A. actinomycetemcomitans-positive patients, a significantly positive correlation was observed between antibody titer and avidity to serotype c. A. actinomycetemcomitans-positive patients with generalized aggressive periodontitis showed lower IgG avidities to serotype c than those with chronic periodontitis, though no statistically significant difference was found. CONCLUSION: A. actinomycetemcomitans serotype c may play a significant role in chronic and generalized aggressive periodontitis, while A. actinomycetemcomitans serotype b may be associated with localized aggressive periodontitis in a Japanese population.  相似文献   
36.
Plasma antibody levels in periodontitis patients and controls   总被引:2,自引:0,他引:2  
BACKGROUND: A major aspect of the adaptive host response in periodontitis is the production of antibodies. Several risk and susceptibility factors for periodontitis, including smoking, age and composition of the subgingival microflora, have also been suggested to influence antibody production. AIM: The present study was conducted to investigate plasma levels of immunoglobulin (Ig) G, A and M antibodies in periodontitis patients of Caucasian European heritage in relation to disease severity, smoking, diagnosis and prevalence of periodontopathogens. METHODS: In this study, 29 patients with severe periodontitis, 51 with moderate periodontitis and 55 controls without periodontal destruction were enrolled. From the total of 80 patients, 18 were diagnosed with aggressive periodontitis and 62 with chronic periodontitis. Total IgG, IgA and IgM as well as IgG isotypes were analyzed in plasma samples. RESULTS: Levels of total IgG, IgA and IgM were not different between patients and controls; however, in periodontitis, higher levels of IgG1 and IgG2 were observed. Smoking appeared to be significantly and inversely related to antibody levels in periodontitis, in particular for total IgG and IgG2. The absence of an elevated total IgG and IgG2 in smoking patients was irrespective of severity, prevalence of periodontal pathogens and diagnosis. The elevation of total IgG and IgG1 and IgG2 in non-smoker periodontitis patients was observed in patients with moderate periodontitis and even greater in patients with severe periodontitis, but was independent whether patients were infected with Actinobacillus actinomycetemcomitans or Porphyromonas gingivalis and independent of diagnosis. Clinically, it was observed that patients who smoked had more periodontal bone loss; the current findings on antibody levels may be one of several mechanisms related to more extensive periodontal breakdown in smoker patients. CONCLUSION: The current study shows that non-smoker periodontitis patients have higher levels of total IgG and IgG2 than smoker periodontitis patients.  相似文献   
37.
The aim of the present study was to discover any possible correlation between specific antibodies against Actinobacillus actinomycetemcomitans (A.a.) in serum and saliva. The test group consisted of 38 patients aged 31–68 yr (mean 49) with advanced periodontitis. Twenty-nine subjects aged 23–67 yr, without periodontal destruction, formed a control group with a reference level of specific salivary antibodies against A.a. A subgingival plaque sample for culturing A.a. , a specimen of stimulated whole saliva, and a sample of venous blood were taken from each subject of the test group. Specific IgG and IgA antibodies against A.a. were determined from serum and stimulated whole saliva by means of the ELISA test. Fifteen of the patients (39%) had cultivable A.a. Six of the 15 A.a. culture-positive patients and one of the 29 reference subjects exhibited very high antibody titers against A.a. in saliva. Specific IgG and IgA antibodies in saliva correlated highly significantly with the corresponding antibody values in serum among the patients in the test group. It was concluded that among patients with severe adult periodontitis, the less invasive saliva sample has a diagnostic value equal to that of the serum sample concerning specific antibodies against A.a.  相似文献   
38.

Objectives

To investigate potential functions of transforming growth factor-beta (TGF-β) isoforms in maturation-stage ameloblasts during amelogenesis.

Methods

In vivo activation of TGF-β was characterized by using matrix metalloproteinase 20 null (Mmp20-/-) and wild-type (Mmp20+/+) mice. Using mHAT9d cells cultured in the presence of each TGF-β isoform, (1) cell proliferation was determined by MTS assay, (2) immunostaining with anti-cleaved caspase-3 monoclonal antibody was performed and apoptotic indices were measured, (3) gene expression was analyzed by RT-qPCR, and (4) the uptake of amelogenin into mHAT9d cells was directly observed using a fluorescence microscope.

Results

TGF-β1 and TGF-β3 were present in the enamel matrix of developing teeth which were activated by MMP20 in vivo. A genetic study revealed that the three TGF-β isoforms upregulate kallikrein 4 (KLK4) mRNA levels but downregulate carbonic anhydrase II. Moreover, TGF-β1 and TGF-β2 significantly upregulated the mRNA level of amelotin, whereas TGF-β3 dramatically downregulated the mRNA levels of odontogenic ameloblast-associated protein (ODAM), family with sequence similarity 83 member H (FAM83H), and alkaline phosphatase (ALP). Immunostaining analysis showed that the apoptosis of mHAT9d cells is induced by three TGF-β isoforms, with TGF-β3 being most effective. Both TGF-β1 and TGF-β3 induced endocytosis of amelogenin.

Conclusions

We propose that TGF-β is regulated in an isoform-specific manner to perform multiple biological functions such as gene expression related to the structure of basal lamina/ameloblasts, mineral ion transport, apoptosis, and endocytosis in maturation-stage ameloblasts.  相似文献   
39.
This study examined the nature of the infiltrating cells in Porphyromonas gingivalis-induced lesions and immunoglobulins in the serum samples of BALB/c (H-2d), C57BL6 (H-2b), DBA/2J (H-2d) and CBA/CaH (H-2k) mice. Mice were immunized intraperitoneally with P. gingivalis outer membrane antigens or sham-immunized with phosphate-buffered saline followed by subcutaneous challenge with live organisms 1 week after the final immunization. The resulting skin abscesses were excised 7 days later, cryostat sections cut and an immunoperoxidase method used to detect the presence of CD4+ and CD8+ T-cell subsets, CD14+ macrophages and CD19+ B cells. Peroxidase positive neutrophils and IgG1- and IgG2a-producing plasma cells were also identified. Anti P. gingivalis IgG1 and IgG2a subclass antibodies were determined in serum obtained by cardiac puncture. Very few CD8+ T cells and CD19+ B cells were found in any of the lesions. The percentages of CD4+ cells, CD14+ cells and neutrophils were similar in lesions of immunized BALB/c and C57BL6 mice, with a trend towards a higher percentage of CD14+ cells in sham-immunized mice. The percentage of CD14+ cells was higher than that of CD4+ cells in immunized compared with sham-immunized DBA/2J mice. The percentages of CD4+ and CD14+ cells predominated in immunized CBA/CaH mice and CD4+ cells in sham-immunized CBA/CaH mice. The percentage of neutrophils in immunized CBA/CaH mice was significantly lower than that of CD14+ cells and CD4+ cells in sham-immunized mice. IgG1+ plasma cells were more dominant than IgG2a+ cells in immunized BALB/c, C57BL6 and DBA/2J mice, whereas IgG2a+ plasma cells were more obvious in sham-immunized mice. IgG2a+ plasma cells were predominant in immunized and sham-immunized CBA/CaH mice. In the serum, specific anti-P. gingivalis IgG2a antibody levels (Th1 response) were higher than IgG1 levels (Th2 response) in sham-immunized CBA/CaH and DBA/2J mice. In immunized BALB/c mice, IgG2a levels were lower than IgG1 levels, while IgG2a levels were higher in immunized C57BL6 mice. In conclusion, this study has shown differences in the proportion of infiltrating leukocytes and in the subclasses of immunoglobulin produced locally and systemically in response to P. gingivalis in different strains of mice, suggesting a degree of genetic control over the response to P. gingivalis.  相似文献   
40.
Successive immunization of mice with Fusobacterium nucleatum and Porphyromonas gingivalis has been shown to modulate the specific serum IgG responses to these organisms. The aim of this study was to investigate these antibody responses further by examining the IgG subclasses induced as well as the opsonizing properties of the specific antibodies. Serum samples from BALB/c mice immunized with F. nucleatum (gp1-F), P. gingivalis (gp2-P), P. gingivalis followed by F. nucleatum (gp3-PF) F. nucleatum followed by P. gingivalis (gp4-FP) or saline alone (gp5-S) were examined for specific IgG1 (Th2) and IgG2a (Th1) antibody levels using an ELISA and the opsonizing properties measured using a neutrophil chemiluminescence assay. While IgG1 and IgG2a subclasses were induced in all immunized groups, there was a tendency towards an IgG1 response in mice immunized with P. gingivalis alone, while immunization with F. nucleatum followed by P. gingivalis induced significantly higher anti-P. gingivalis IgG2a levels than IgG1. The maximum light output due to neutrophil phagocytosis of P. gingivalis occurred at 10 min using nonopsonized bacteria. Chemiluminescence was reduced using serum-opsonized P. gingivalis and, in particular, sera from P. gingivalis-immunized mice (gp2-P), with maximum responses occurring at 40 min. In contrast, phagocytosis of immune serum-opsonized F. nucleatum demonstrated peak light output at 10 min, while that of F. nucleatum opsonized with sera from saline injected mice (gp5-S) and control nonopsonized bacteria showed peak responses at 40 min. The lowest phagocytic response occurred using gp4-FP serum-opsonized F. nucleatum. In conclusion, the results of the present study have demonstrated a systemic Th1/Th2 response in mice immunized with P. gingivalis and/or F. nucleatum with a trend towards a Th2 response in P. gingivalis-immunized mice and a significantly increased anti-P. gingivalis IgG2a (Th1) response in mice immunized with F. nucleatum prior to P. gingivalis. Further, the inhibition of neutrophil phagocytosis of immune serum-opsonized P. gingivalis was modulated by the presence of anti-F. nucleatum antibodies, while anti-P. gingivalis antibodies induced an inhibitory effect on the phagocytic response to F. nucleatum.  相似文献   
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