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61.
62.
Gilbert  HS; Praloran  V; Stanley  ER 《Blood》1989,74(4):1231-1234
Myeloproliferative disease (MPD) is heterogeneous in phenotypic expression and may display features consistent with expansion and activation of the monocyte/macrophage population during its course. The role of colony-stimulating factor-1 (CSF-1) in the pathophysiology of MPD was investigated by measuring circulating CSF-1 levels and examining their relationship to disease phenotype. Serum CSF-1 concentrations, measured by radioimmunoassay, were elevated in all MPD phenotypes. CSF-1 levels differed significantly between groups of patients with essential thrombocythemia, polycythemia vera, and postpolycythemic or agnogenic myeloid metaplasia (in ascending order). CSF-1 serum levels were positively correlated with spleen size and the degree of peripheral bone marrow extension, determined by scintigraphy using a macrophage-seeking isotope. There was no correlation between CSF-1 concentration and circulating levels of erythrocytes, neutrophils or platelets, or the presence of bone marrow fibrosis. Elevated serum CSF-1 levels appear to be associated with an expanded monocyte/macrophage population in MPD. In view of the known cooperativity between CSF-1 and other growth factors in regulating hematopoiesis, the finding of increased serum CSF-1 concentrations and its association with myeloid metaplasia and bone marrow extension may indicate a pathophysiologic role for CSF-1 in determining the phenotypic expression of MPD.  相似文献   
63.
The vanadate-based phosphors Sr2V2O7:Eu3+ (SV:Eu3+), Sr9Gd(VO4)7:Eu3+ (SGV:Eu3+) and Sr9Gd(VO4)7/Sr2V2O7:Eu3+ (SGV/SV:Eu3+) were obtained by solid-state reaction. The bond-energy method was used to investigate the site occupancy preference of Eu3+ based on the bond valence model. By comparing the change of bond energy when the Eu3+ ions are incorporated into the different Sr, V or Gd sites, we observed that Eu3+ doped in SV, SGV or SV/SGV would preferentially occupy the smaller energy variation sites, i.e., Sr4, Gd and Gd sites, respectively. The crystal structures of SGV and SV, the photoluminescence properties of SGV:Eu3+, SV, SGV/SV and SGV/SV:Eu, as well as their possible energy transfer mechanisms are proposed. Interesting tunable colours (including warm-white emission) of SGV/SV:Eu3+ can be obtained through changing the concentration of Eu3+ or changing the relative quantities of SGV to SV by increasing the calcination temperature. Its excitation bands consist of two types of O2− → V5+ charge transfer (CT) bands with the peaks at about 325 and 350 nm respectively, as well as f–f transitions of Eu3+. The obtained warm-white emission consists of a broad photoluminescence band centred at about 530 nm, which originates from the O2− → V5+ CT of SV, and a sharp characteristic spectrum (5D07F2) at about 615 and 621 nm.

The vanadate-based phosphors Sr2V2O7:Eu3+ (SV:Eu3+), Sr9Gd(VO4)7:Eu3+ (SGV:Eu3+) and Sr9Gd(VO4)7/Sr2V2O7:Eu3+ (SGV/SV:Eu3+) were obtained by solid-state reaction.  相似文献   
64.
65.
Background: Nephrotoxicity associated with lead poisoning has been frequently reported in epidemiological studies, but the underlying mechanisms have not been fully described.Objectives: We examined the role of erythrocytes, one of the major lead reservoirs, in lead-associated nephrotoxicity.Methods and results: Co-incubation of lead-exposed human erythrocytes with HK-2 human renal proximal tubular cells resulted in renal tubular cytotoxicity, suggesting a role of erythrocytes in lead-induced nephrotoxicity. Morphological and flow cytometric analyses revealed that HK-2 cells actively phagocytized lead-exposed erythrocytes, which was associated with phosphatidylserine (PS) externalization on the erythrocyte membrane and generation of PS-bearing microvesicles. Increased oxidative stress and up-regulation of nephrotoxic biomarkers, such as NGAL, were observed in HK-2 cells undergoing erythrophagocytosis. Moreover, TGF-β, a marker of fibrosis, was also significantly up-regulated. We examined the significance of erythrophagocytosis in lead-induced nephrotoxicity in rats exposed to lead via drinking water for 12 weeks. We observed iron deposition and generation of oxidative stress in renal tissues of lead-exposed rats, as well as the histopathological alterations such as tubulointerstitial lesions, fibrosis, and up-regulation of KIM-1, NGAL, and TGF-β.Conclusions: Our data strongly suggest that erythrophagocytosis and subsequent iron deposition in renal tubular cells could significantly enhance nephrotoxicity following lead exposure, providing insight on lead-associated kidney damages.Citation: Kwon SY, Bae ON, Noh JY, Kim K, Kang S, Shin YJ, Lim KM, Chung JH. 2015. Erythrophagocytosis of lead-exposed erythrocytes by renal tubular cells: possible role in lead-induced nephrotoxicity. Environ Health Perspect 123:120–127; http://dx.doi.org/10.1289/ehp.1408094  相似文献   
66.
Proliferating trichilemmal tumor (PTT) is a rare tumor that originates from the outer root sheath of a hair follicle. About 90% of PTTs occur on the scalp. The sonographic findings of PTT in the subungual region have not been reported previously. In our case, sonography showed a heterogeneous mass containing echogenic foci with no detectable intratumoral vascularity. These echogenic foci probably represent keratin and cholesterol. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 46 :215–217, 2018  相似文献   
67.
Purpose: To examine factors in the fear-avoidance model, such as pain, pain catastrophizing, fear-avoidance beliefs, physical disability, and depression and their relationships with physical and psychological quality of life in patients with rheumatic diseases.

Materials and methods: The data were obtained from 360 patients with rheumatic diseases who completed self-report measures assessing study variables. Structural equation modeling was used to examine the hypothesized relationships among factors specified in the fear-avoidance model predicting physical and psychological quality of life.

Results: Final models fit the data well, explaining 96% and 82% of the variance in physical and psychological quality of life, respectively. Higher pain catastrophizing was related to stronger fear-avoidance beliefs that had a direct negative association with physical disability and depression, which, in turn, negatively affected physical quality of life. Pain severity was also directly related to physical disability. Physical disability also affected physical quality of life indirectly through depression. The hypothesized relationships specified in the model were also confirmed for psychological quality of life. However, physical disability had an indirect association with psychological quality of life via depression.

Conclusion: The current results underscore the significant role of cognitive, affective, and behavioral factors in perceived physical disability and their mediated detrimental effect on physical and psychological quality of life in patients with rheumatic diseases.

  • Implications for rehabilitation
  • The fear-avoidance model is applicable to the prediction of quality of life in patients with rheumatic diseases.

  • As pain-catastrophizing and fear-avoidance beliefs are important factors linked to physical disability and depression, intervening these cognitive factors is necessary to improve physical function and depression in patients with rheumatic diseases.

  • Considering the strong association between depression and physical and psychological quality of life, the assessment and treatment of the former should be included in the rehabilitation of patients with rheumatic diseases.

  • Interventions targeting physical function and depression are likely to be effective in terms of improving physical and psychological quality of life in patients with rheumatic diseases.

  相似文献   
68.

Objectives:

This study aimed to investigate North Korean refugees’ knowledge of mental illnesses and treatments and analyze the factors affecting this knowledge.

Methods:

Subjects were selected via a snowball sampling method, and the survey outcomes of 152 North Korean refugee participants were analyzed. The factors affecting knowledge of mental illnesses were analyzed via a regression analysis by constructing a multivariate model with mental illness knowledge score as the dependent variable.

Results:

The North Korean refugees’ mental illness scores ranged from 3 to 24 points, with an average score of 13.0. Regarding the factors that influence mental illness knowledge, the subjects with South Korean spouses and those who had spent more time in South Korea had higher knowledge scores. Furthermore, the subjects who considered the mental health of North Korean refugees to be a serious issue revealed lower knowledge scores than those who did not believe it was a serious issue. The subjects who visit psychiatric clinics showed higher knowledge scores than those who do not. The South Korean subjects who had at least a college education exhibited higher scores than did those without advanced education. The subjects who are satisfied with life in South Korea manifested a higher mental illness knowledge score than those who are not.

Conclusions:

This study is significant as being the first study to ever measure and evaluate the level of North Korean refugees’ knowledge of mental illnesses. In addition, the evaluations of North Korean refugees’ mental illness knowledge and influencing factors while residing in South Korea created basic data that formed the foundation of an effort to enhance mental health literacy and provide proper mental health services. The results of this study can be utilized to solve mental health problems that might frequently occur during the unification process of North and South Korea in the future.  相似文献   
69.
AIM: rAAV mediated endostatin gene therapy has been examined as a new method for treating cancer. However, a sustained and high protein delivery is required to achieve the desired therapeutic effects. We evaluated the impact of topoisomerase inhibitors in rAAV delivered endostatin gene therapy in a liver tumor model. METHODS: rAAV containing endostatin expression cassettes were transduced into hepatoma cell lines. To test whether the topoisomerase inhibitor pretreatment increased the expression of endostatin, Western blotting and ELISA were performed. The biologic activity of endostatin was confirmed by endothelial cell proliferation and tube formation assays. The anti-tumor effects of the rAAV-endostatin vector combined with a topoisomerase inhibitor, etoposide, were evaluated in a mouse liver tumor model. RESULTS: Topoisomerase inhibitors, including camptothecin and etoposide, were found to increase the endostatin expression level in vitro. The over-expressed endostatin, as a result of pretreatment with a topoisomerase inhibitor, was also biologically active. In animal experiments, the combined therapy of topoisomerase inhibitor, etoposide with the rAAV-endostatin vector had the best tumor-suppressive effect and tumor foci were barely observed in livers of the treated mice. Pretreatment with an etoposide increased the level of endostatin in the liver and serum of rAAV-endostatin treated mice. Finally, the mice treated with rAAV-endostatin in combination with etoposide showed the longest survival among the experimental models. CONCLUSION: rAAV delivered endostatin gene therapy in combination with a topoisomerase inhibitor pretreatment is an effective modality for anticancer gene therapy.  相似文献   
70.
In 24 (0.98%) of 2457 patients with congenital heart disease the brachiocephalic vein was in an anomalous position below the aortic arch. This is a much higher proportion of such cases than reported so far. This high frequency may arise from differences in the study population and the method of diagnosis. This venous anomaly was more common in patients with tetralogy of Fallot or ventricular septal defect with pulmonary atresia. Patients with the venous anomaly were more likely to have a right aortic arch. The anomalous course of the brachiocephalic vein from the neck to the junction of the superior vena cava was shown by cross sectional echocardiography. In doubtful cases, Doppler study usually clarified the anatomical arrangement.  相似文献   
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