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61.
The clinical syndrome of aspirin-intolerant asthma (AIA) is characterized by aspirin/nonsteroidal anti-inflammatory drug intolerance, bronchial asthma, and chronic rhinosinusitis with nasal polyposis. AIA reactions are evidently triggered by pharmacological effect of cyclooxygenase-1 inhibitors. Urine sampling is a non-invasive research tool for time-course measurements in clinical investigations. The urinary stable metabolite concentration of arachidonic acid products provides a time-integrated estimate of the production of the parent compounds in vivo. AIA patients exhibits significantly higher urinary concentrations of leukotriene E(4) (LTE(4)) and 1,15-dioxo-9α-hydroxy-2,3,4,5-tetranorprostan-1,20-dioic acid (tetranor-PGDM), a newly identified metabolite of PGD(2), at baseline. This finding suggests the possibility that increased mast cell activation is involved in the pathophysiology of AIA even in a clinically stable condition. In addition, lower urinary concentrations of primary prostaglandin E(2) and 15-epimer of lipoxin A(4) at baseline in the AIA patients suggest that the impaired anti-inflammatory elements may also contribute to the severe clinical outcome of AIA. During the AIA reaction, the urinary concentrations of LTE(4) and PGD(2) metabolites, including tetranor-PGDM significantly and correlatively increase. It is considered that mast cell activation probably is a pathophysiologic hallmark of AIA. However, despite the fact that cyclooxygenease-1 is the dominant in vivo PGD(2) biosynthetic pathway, the precise mechanism underlying the PGD(2) overproduction resulting from the pharmacological effect of cyclooxygenease-1 inhibitors in AIA remains unknown. A comprehensive analysis of the urinary concentration of inflammatory mediators may afford a new research target in elucidating the pathophysiology of AIA.  相似文献   
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63.
Objective: Pregnancy hypertension is the most common gestational complication and poses a critical risk for mother and fetus. Whether environmental factors may play an important role in disease occurrence is not fully determined. Methods: To investigate the effects of prenatal manganese (Mn) exposure on gestational blood pressure, 386 women were examined. Results: Early pregnancy blood Mn was significantly (p < 0.05) correlated with blood pressure through gestation. A significant association between odds of pre-hypertension with blood Mn was shown (OR:1.150, 95% CI:1.052–1.258). Conclusion: The current study results might suggest the blood Mn level during early stage of pregnancy as a potential risk factor for increasing the risk of gestational blood pressure.  相似文献   
64.
We herein report the rare case of a 4‐year–5‐month‐old boy who presented with primary renal neuroblastoma. The patient developed repeated lung and liver metastatic recurrences, but, following a combination of chemotherapy, radiation therapy and aggressive surgical resection, the patient is now in remission. To investigate the pathogenesis of lung metastasis, immunohistochemistry was performed for matrix metalloproteinase‐9 and ‐14 (MMP‐9 and MMP‐14), molecular markers of invasion, metastasis and angiogenesis in neuroblastoma. In the present case, MMP‐9 expression was not observed, but MMP‐14 expression was detected in the primary lesion and was more highly expressed in the metastatic lesion compared with the primary one. Given the MMP‐14 staining in other cases, expression of MMP‐14 may be associated with the aggressiveness of the tumor. This suggests that selected clones with high MMP‐14 expression in the primary tumor might metastasize and form MMP‐14‐rich lesions.  相似文献   
65.

Background

The Oxford classification of IgA nephropathy consists of four markers as prognosticators. We retrospectively examined the relevance of extracapillary proliferation involving cellular and fibrocellular crescents (Ex) and arteriolar hyalinosis (A) on the long-term outcome of renal function.

Methods

A total of 314 Japanese patients who were diagnosed with IgA nephropathy, with 12 months or more of follow-up period were included in this study. A total of 186 patients were with UP ≥ 0.5 g/day. Patients with diabetes mellitus or severe kidney injury (eGFR < 30 ml/min/1.73 m2) were excluded. The presence of Ex and A were scored 0 in the absence, and 1 in the presence, of each lesion. The end point was determined as a 50 % reduction in initial eGFR or end-stage renal disease defined as eGFR < 15 ml/min/1.73 m2.

Results

In univariate analyses, the kidney survival rate was significantly lower in patients with Ex1 and A1 if UP ≥ 0.5 g/day. In the patients with UP < 0.5/day, none of the clinical and pathological parameters was determined as a risk factor. In the multivariate model including pathological parameters, Ex1 and A1 were independent risk factors for renal outcome if UP ≥ 0.5 g/day. In those patients treated with RAS-blocker or treated before introduction of methylprednisolone pulse therapy, Ex was the only independent risk factor. In multivariate analysis including clinical parameters, eGFR alone was a risk factor, due to strong correlation with other parameters.

Conclusion

Ex and A would be associated with the renal outcome of the patients with UP ≥ 0.5 g/day.
  相似文献   
66.

Background

Chemical intolerance is a widespread public health problem characterized by symptoms that reportedly result from low-level exposure to chemicals. Although several studies have reported factors related to chemical intolerance in adults, the impact of family members has not been reported. In the present study, we investigated the background factors related to chemical intolerance in family members and parent–child relationships.

Methods

We distributed a self-reported questionnaire to 4325 mothers who were invited to visit the Kishiwada Health Center in Kishiwada City, Osaka, between January 2006 and December 2007 for the regular health checkup of their three-and-a-half-year-old children.

Results

The prevalence of chemical intolerance in the 3-year-old children was almost one eighteenth of that reported by their mothers. Multiple logistic regression analyses revealed that cold sensitivity [odds ratio (OR), 1.89; 95% confidence interval (CI), 1.04–3.44], past bronchial asthma (OR, 2.84; 95% CI, 1.46–5.53), and any past allergies (OR, 2.21; 95% CI, 1.36–3.60) were significantly associated with chemical intolerance in the mother. The presence of indoor cat during childhood (OR, 1.99; 95% CI, 1.08–3.69) was significantly associated with chemical intolerance in the mother; however, the association was weak compared with cold sensitivity and past asthma and allergies. The current chemical intolerance of the mother was significantly associated with allergic rhinitis (OR, 2.32; 95% CI, 1.19–4.53), bronchial asthma (OR, 3.66; 95% CI, 2.00–6.69), and chronic bronchitis (OR, 3.69; 95% CI, 1.04–13.03) in her 3-year-old child.

Conclusions

The results suggest that inherent physical constitution and childhood housing environment are associated with a risk of acquiring chemical intolerance. Children of mothers with chemical intolerance have a possible risk of respiratory hypersensitivity or inflammation. Further investigation is recommended to determine the inherent physical constitution and background environmental factors associated with the risk of acquiring chemical intolerance. The impact of having mothers with chemical intolerance on the health of children also requires further study.
  相似文献   
67.
We describe a higher magnifying power operating microscope system to improve one method of high-quality microsurgical clipping for cerebral aneurysm in some cases. This higher magnification is achieved by a new lens design in the optical system, which makes the image of the object very clear at high magnifications (distinctiveness of 7 μm). This higher-resolution operating microscope system provides the surgeon with higher-magnified images (at the maximum of more than 30× magnifications as each working distance) in the operating field. The magnifications can be changed from low power (2.9×) to high power (62.0×) depending on the circumstances in a given procedure. We have used this operating microscope system on 11 patients with microsurgical clipping for cerebral aneurysms. Microsurgical treatment could be performed safely and precisely. All aneurysms were treated without any technical complications. We think that the use of this microscope would have potential benefits for microsurgical treatment for cerebral aneurysms because of better visualization.  相似文献   
68.
Immune networks in animal models of inflammatory bowel disease   总被引:5,自引:0,他引:5  
The animal models of inflammatory bowel disease provide a framework to define the immunopathogenesis of intestinal inflammation. Studies in these models support the hypothesis that exaggerated immune responses to normal enteric microflora are involved in the initiation and perpetuation of chronic intestinal inflammation. A major pathway involves development of acquired immune responses by the interactions of CD4+ T-cell receptor alphabeta T cells with antigen-presenting cells (dendritic cells). Immunoregulatory cells, including Tr1 cells, Th3 cells, and CD4+ CD25+ T cells and B cells, directly or indirectly affect the T-cell receptor alphabeta T cell-induced immune responses and bridge innate and acquired immunity. The study of these complicated immune networks provides the rationale for the development of new therapeutic interventions in inflammatory bowel disease.  相似文献   
69.
OBJECTIVE: To clarify the signaling mechanism of human myeloid differentiation by hematopoietic growth factors and cytokines, we investigated the role of extracellular signal-regulated kinase (ERK) during the differentiation of human monoblastic U937 cells stimulated by granulocyte-macrophage colony-stimulating factor (GM-CSF) and tumor necrosis factor (TNF). MATERIALS AND METHODS: Myeloid differentiation was evaluated by morphology, function (respiratory burst activity), and cell surface expression of adhesion molecule (CD11b), and activation of ERK and/or p38 was determined by Western blotting and/or in vitro kinase assay. Inhibition of the ERK pathway was performed using PD98059, a specific inhibitor of this pathway. RESULTS: U937 cells were induced to be differentiated by the combination of GM-CSF and TNF, but only minimally by either cytokine alone. Transient phosphorylation and activation of ERK was induced by both GM-CSF alone and combination of the two cytokines, whereas sustained phosphorylation and activation was induced only by the combination. In addition, PD98059, a specific inhibitor of ERK pathway, almost completely abolished this prolonged phosphorylation of ERK and completely blocked differentiation. In contrast, both TNF alone and cytokine combination equivalently phosphorylated p38 in U937 cells, which was dissociated from differentiation, and a specific inhibitor of p38 (SB203580) did not inhibit differentiation. CONCLUSIONS: The results indicate potential roles of sustained activation of ERK but not of p38 in the signaling pathways for human myeloid differentiation in U937 cells synergistically stimulated by the two physiologic cytokines GM-CSF and TNF.  相似文献   
70.
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