Experimental testing of a DEXA-derived curved beam model of the proximal femur

This study was designed to test whether, using curved beam theory, a structural model of the proximal femur derived from two-dimensional dual energy x-ray absorptiometry could be used to predict femoral strength in an experimental simulation of a fall on the greater trochanter. A set of 22 fresh cadaveric femoral specimens were scanned with use of two-dimensional dual energy x-ray absorptiometry and then were tested to failure in a materials testing system, under three-point loading, with the ground impact vector, aligned within the plane and along the bisector of the femoral neck-shaft angle. Failure locations generally corresponded to stress peak locations predicted by the curved beam model. Predicted failure loads correlated well with measured failure loads for femoral neck fractures (r = 0.89; percent SE of estimate = 23%) and somewhat less well for intertrochanteric fractures (r = 0.83; percent SE of estimate = 29%). Overall predictions for failure load calculated from the maximum stress peak value over both locations corresponded to measured failure loads with an r value of 0.91 (percent SE of estimate = 21%). This kind of structural approach to the analysis of data for hip bone mass has the potential to provide mechanistic interpretations of the statistical associations frequently shown between conventional bone mineral measures and either hip fracture risk in vivo or bone strength in vitro.     

中国羊踯躅花化学成分研究

从国产杜鹃花科植物羊踯躅(Rhododendron molle G.Don)的花中分离得到两种有药理活性的成分。经光谱(IR,MS,¹HNMR,¹³CNMR,¹H-¹H COSY,¹H-¹H NOESY,¹³C-¹H COSY)等分析证明其中一种为新的四环二萜类化合物。命名为羊踯躅素Ⅲ(rhodomollein Ⅲ)(1)。     

Development of the Expectations of Filial Piety Scale--Spanish version

AIMS: This paper reports the development of the Expectations of Filial Piety Scale for use with Hispanic/Latino parents regarding their expectations of care and support from their adult children. BACKGROUND: Filial piety, a term used to describe a set of family values in relation to parental care and respect, has strong cultural underpinnings. To date, there have been no measures of this construct for use with Hispanic/Latino populations. METHODS: A convenience sample of 318 Hispanic/Latino adults in North Carolina and Texas in the United States of America completed a brief biographical survey and field-tested a new Spanish version of the Expectations of Filial Piety Scale in 2003. RESULTS: Principal component factor analysis with orthogonal rotation (varimax method) was used to extract four factors, which accounted for 60% of the variance in scale scores. These factors were: I, respect for parents (23.6%); II, honouring parents (12.5%); III, supporting parents (11.9%); and IV, family unity (11.7%). Overall scale reliability was 0.82, with individual factor reliability coefficients ranging from 0.66 to 0.84. CONCLUSIONS: Increasingly, large numbers of Hispanic/Latino elders will look to their families for support as they reach advanced ages. Culturally relevant translations of family caregiving constructs, such as filial piety, will be essential nursing tools for clinical practice and in developing contemporary family caregiver research agendas.     

Soluble lumican glycoprotein purified from human amniotic membrane promotes corneal epithelial wound healing

PURPOSE: To purify and characterize the glycoprotein lumican, isolated from human amniotic membrane (AM), and to examine its efficacy in treating corneal epithelium debridement. METHODS: An affinity-purified, anti-human lumican antibody-conjugated protein A Sepharose column was used to purify soluble lumican protein from human AM. The purified AM lumican was characterized by two-dimensional and SDS gel electrophoresis, plus Western blot analysis with anti-lumican antibody. The effects of lumican on corneal epithelial wound healing were examined in an organ culture mouse eye model. RESULTS: Lumican was found to be abundantly present in the stroma of human AM. It was extracted from the AM by isotonic, 1 M NaCl, and 4 M guanidine HCl solutions, suggesting that it is present in both the soluble and matrix-bound states. In two-dimensional gel electrophoresis, the 50-kDa human amniotic lumican purified by antibody-conjugated affinity chromatography migrated in a smear between pH 3.0 and 6.0. After endo-beta-galactosidase digestion, it existed as a single core protein at pH 6.0, suggesting that native human amniotic lumican is a glycoprotein with short sugar moiety. Addition of purified human AM lumican to cultured medium promoted re-epithelialization and enhanced cell proliferation of wild-type mouse corneal epithelial cells in an organ culture. In lumican-knockout (lum(-/-)) mice, the effect of human lumican on promoting corneal epithelial wound healing was even more dramatic than in wild-type mice. CONCLUSIONS: The diversified functions of lumican include modulation of epithelial cells in wound healing and serving as an extracellular matrix component. Administration of lumican may be beneficial for treating epithelial defects in the cornea and other tissues.     

H-Ras oncogene counteracts the growth-inhibitory effect of genistein in T24 bladder carcinoma cells

Among eight human bladder cancer cell lines we examined, only T24 cells were resistant to the growth inhibition effect of genistein, an isoflavone and potent anticancer drug. Since the T24 cell line was the only cell line known to overexpress oncogenic H-Ras(val 12), we investigated the role of H-Ras(val 12) in mediating drug resistance. Herein, we demonstrate that the phenotype of T24 cells could be dramatically reversed and became relatively susceptible to growth inhibition by genistein if the synthesis of H-Ras(val 12) or its downstream effector c-Fos had been suppressed. The inhibition of Ras-mediated signalling with protein kinase inhibitors, such as PD58059 and U0126 which inhibited MEK and ERK, in T24 cells also rendered the identical phenotypic reversion. However, this reversion was not observed when an inhibitor was used to suppress the protein phosphorylation function of PI3 K or PKC. These results suggest that the signal mediated by H-Ras(val 12) is predominantly responsible for the resistance of the cells to the anticancer drug genistein.     

Tetramethylpyrazine downregulates angiotensin II-induced endothelin-1 gene expression in vascular endothelial cells

1. Tetramethylpyrazine (TMP) is one of the active ingredients of the Chinese herb Ligusticum wallichii Franchat. It is well documented that TMP exerts a cardiovascular protective effect. The aims of the present study were to examine whether TMP alters angiotenisn (Ang) II-induced endothelin (ET)-1 gene expression and to identify the putative underlying signalling pathways in vascular endothelial cells. 2. Cultured vascular endothelial cells were pre-incubated with TMP, stimulated with AngII and ET-1 gene expression was then examined. The effects of TMP pretreatment on AngII-induced extracellular signal-regulated kinase (ERK) phosphorylation were investigated to elucidate the intracellular mechanism responsible for the effects of TMP on ET-1 gene expression. 3. Tetramethylpyrazine inhibited AngII-induced ET-1 gene expression, as revealed by nothern blotting and a promoter activity assay. Tetramethylpyrazine also inhibited the AngII-induced increase in intracellular reactive oxygen species (ROS), as measured by the redox sensitive fluorescent dye 2' 7'-dichlorofluorescin diacetate and ERK phosphorylation. 4. In summary, we have demonstrated, for the first time, that TMP inhibits AngII-induced ROS generation, ERK phosphorylation and ET-1 gene expression in vascular endothelial cells. Thus, the present study delivers important new insights into the molecular pathways that may contribute to the proposed beneficial effects of TMP in the cardiovascular system.     

Use of the Beers criteria to predict adverse drug reactions among first-visit elderly outpatients

STUDY OBJECTIVE: To determine whether the Beers criteria can predict adverse drug reactions (ADRs) in first-visit elderly outpatients. DESIGN: Prospective cohort study. SETTING: Outpatient clinics of a tertiary care and academic medical center in southern Taiwan. PATIENTS: Eight hundred eighty-two patients aged 65 years or older who were prescribed drugs at their first visit to either the medical center's outpatient internal medicine clinic or family medicine clinic between March 1, 2001, and July 31, 2001. INTERVENTION: Telephone survey conducted 1 week after clinic visit. MEASUREMENTS AND MAIN RESULTS: Potentially inappropriate drugs were assessed by the updated Beers criteria. Adverse drug reactions were detected by telephone survey and evaluated by the Naranjo criteria 1 week after drug administration. Of the 550 respondents, 64 (11.6%) had potentially inappropriate drugs prescribed and 126 (22.9%) had ADRs. Multiple logistic regression analysis revealed associations between ADRs and potentially inappropriate drug prescribing (relative risk [RR] 15.3, 95% confidence interval [CI] 4.0-58.8), number of prescribed drugs (RR 1.3, 95% CI 1.1-1.5), history of ADRs (RR 2.1, 95% CI 1.3-3.4), and noncompliance with prescribed drugs (RR 2.0, 95% CI 1.1-3.7). In patients who had potentially inappropriate drugs prescribed, the number of prescribed drugs was not significantly associated with ADRs (RR 0.8, 95% CI 0.6-1.1). In patients who did not have potentially inappropriate drugs prescribed, more prescribed drugs increased the risk of ADRs (RR 1.3, 95% CI 1.1-1.5). CONCLUSION: A positive association exists between potentially inappropriate drug prescribing, as defined by the Beers criteria, and ADRs in first-visit elderly outpatients. Clinicians should be alert to the possibility of ADRs if a patient takes more than five drugs, has a history of ADRs, or exhibits poor compliance with prescribed drugs.