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991.
MicroCT evaluation of three-dimensional mineralization in response to BMP-2 doses in vitro and in critical sized rat calvarial defects 总被引:1,自引:0,他引:1
Cowan CM Aghaloo T Chou YF Walder B Zhang X Soo C Ting K Wu B 《Tissue engineering》2007,13(3):501-512
Numerous growth factors, peptides, and small molecules are being developed for bone tissue engineering. The optimal dosing, stability, and bioactivity of these biological molecules are likely influenced by the carrier biomaterial. Efficient evaluation of various formulations will require objective evaluation of in vitro culture systems and in vivo regeneration models. The objective of this paper is to examine the utility of microcomputed tomography (microCT) over conventional techniques in the evaluation of the bone morphogenetic protein-2 (BMP-2) dose response effect in a three-dimensional (3D) in vitro culture system and in an established calvarial defect model. Cultured MC3T3-E1 osteoblasts displayed increased cellular density, extracellular matrix (ECM) production, and mineralization on 3D poly(lactic-co-glycolic acid) (PLGA) scaffolds in a BMP-2 dose dependent manner. MicroCT revealed differences in shape and spatial organization of mineralized areas, which would not have been possible through conventional alizarin red staining alone. Additionally, BMP-2 (doses of 30 to 240 ng/mm(3)) was grafted into 5 mm critical sized rat calvarial defects, where increased bone regeneration was observed in a dose dependent manner, with higher doses of BMP-2 inducing greater bone area, volume, and density. The data revealed the utility of microCT analysis as a beneficial addition to existing techniques for objective evaluation of bone tissue engineering and regeneration. 相似文献
992.
993.
Zhou H Jiao Z Pan J Hong J Tao J Li N Zhou Y Zhang J Chou KY 《Clinical immunology (Orlando, Fla.)》2007,122(3):312-322
The activity of Trichosanthin (Tk) has been attributed to its toxicity since this plant protein was used as an anti-HIV agent. However, in this study strong inhibition of human lymphoproliferation to soluble and allogeneic antigens was induced by Tk at 0.005-0.5 microg/ml without causing cell damages including apoptosis. The suppression was dependent on the presence of monocytes that are able to internalize and process Tk molecules as exogenous antigens. Among 39 Tk-primed T cell lines established, those with strong suppressive activity were CD8(+) TCRalphabeta(+) with type 2 cytokine secretion profile. Depletion of CD8 cells from total T cells or blocking expression of HLA-DQ molecules diminished Tk's inhibitory activity. In addition, healthy subjects with HLA haplotype DRB1*0301-DQA1*0501-DQB1*0201 were susceptible to the hyporeaction induced by Tk or a Tk-derived peptide. This indicates that Tk could induce an HLA-associated immune suppression via activating IL-4/IL-10-secreting T cells, which might belong to CD8 Tc2 subset. 相似文献
994.
Daniel Kotz Geertjan Wesseling Marcus JH Huibers Onno CP van Schayck 《BMC public health》2007,7(1):332
Background
The use of spirometry for early detection of chronic obstructive pulmonary disease (COPD) is still an issue of debate, particularly because of a lack of convincing evidence that spirometry has an added positive effect on smoking cessation. We hypothesise that early detection of COPD and confrontation with spirometry for smoking cessation may be effective when applying an approach we have termed "confrontational counselling"; a patient-centred approach which involves specific communication skills and elements of cognitive therapy. An important aspect is to confront the smoker with his/her airflow limitation during the counselling sessions. The primary objective of this study is to test the efficacy of confrontational counselling in comparison to regular health education and promotion for smoking cessation delivered by specialized respiratory nurses in current smokers with previously undiagnosed mild to moderate airflow limitation. 相似文献995.
Xie B Chou CP Spruijt-Metz D Reynolds K Clark F Palmer PH Gallaher P Sun P Guo Q Johnson CA 《American journal of health behavior》2007,31(4):339-352
OBJECTIVE: To investigate over-weight prevalence and socio-demographic and economic correlates in Chinese adolescents. METHODs: Weight, height, waist circumference, and socio-demo-graphic and economic variables of 6863 middle and high school students were measured. RESULTS: 10% of girls and 17% of boys were overweight. Waist circumference and overweight risk were significantly associated with pubertal status (P<0.05). High levels of parental education and family income were significant risk factors for overweight (P<0.05). DISCUSSION: Our findings underscore the need for development of evidence-based and culturally appropriate public health programs to prevent and treat pediatric obesity in China. 相似文献
996.
997.
Wang TH Wei KC Hsiung CA Maloney SA Eidex RB Posey DL Chou WH Shih WY Kuo HS 《American journal of public health》2007,97(Z1):S98-100
Taiwan used quarantine as 1 of numerous interventions implemented to control the outbreak of severe acute respiratory syndrome in 2003. From March 18 to July 31, 2003, 147,526 persons were placed under quarantine. Quarantining only persons with known exposure to people infected with severe acute respiratory syndrome could have reduced the number of persons quarantined by approximately 64%. Focusing quarantine efforts on persons with known or suspected exposure can greatly decrease the number of persons placed under quarantine, without substantially compromising its yield and effectiveness. 相似文献
998.
999.
Lei-Chi Wang Tai-Chi Lin Yi-Chen Yeh Hsiang-Ling Ho Chieh-Chih Tsai Teh-Ying Chou 《Current oncology (Toronto, Ont.)》2021,28(1):918
Primary signet ring cell/histiocytoid carcinoma of the eyelid is a rare ocular malignancy and its diagnosis is often delayed. This neoplasm presents as an insidious, diffusely infiltrative mass in the periocular area that later infiltrates the orbit. An exenteration is usually indicated; however, nearly one-third of patients develop local recurrence or metastasis. Morphologically, it resembles signet ring cell carcinoma of the stomach and breast, raising the possibility of mutations in CDH1, the gene encoding E-cadherin. To determine whether primary signet ring cell/histiocytoid carcinoma harbors the CDH1 mutation or other actionable mutations, we analyzed the tumor tissue via next-generation sequencing. We identified only one case of primary signet ring cell carcinoma of the eyelid with adequate DNA quality for sequencing from the pathological archive during the period 2000 to 2020. A comprehensive evaluation including histopathology, immunohistochemistry, and next-generation sequencing assay was performed on tumor tissue. Immunohistochemically, the tumor exhibited E-cadherin membranous staining with the aberrant cytoplasmic staining of β-catenin. Using next-generation sequencing, we demonstrated the mutation in the CDH1 gene. In addition, other clinically actionable mutations including ERBB2 and PIK3CA were also detected. The alterations in other actionable genes indicate a need for larger studies to evaluate the pathogenesis and potential therapies for primary signet ring cell/histiocytoid carcinoma of the eyelid. 相似文献
1000.
BACKGROUND: This study compares the practice of having the recommended Pap smear test every 3 years among female physicians, female relatives of physicians, and general women of similar socio-economic background. METHODS: This population-based cohort study followed a total of 5,815,781 Taiwanese women from January 2001 to December 2003, who were 30 years of age or older in 2001. Of the total study population, 1950 were physicians and 27,441 were female relatives of physicians. Multiple logistical regression models were used. RESULTS: After adjusting for age, ethnic status, physical disability status, and place of residence, of those women whose monthly insurable income was greater than $NT 40,000, female physicians (OR 0.54, 95% CI: 0.50-060) were the least likely to have undergone at least one Pap smear test during the three-year study period. The physicians' relatives (OR 0.90, 95% CI: 0.87-0.92) were also significantly less likely to take routine Pap smear tests compared to general women with equivalent socio-economic background. CONCLUSIONS: The female physician is a major player in disease prevention with advanced knowledge of the benefits associated with the Pap smear test, but may not adhere any better to the recommendations than the general population. 相似文献