[Interaction of DAXX and human papillomavirus type 16 E2 protein]

The aim of the study was to explore the interactions of human papilloma virus 16 (HPV16) E2 protein and Daxx. The location or co-localization of PML and E2 with Daxx in Caski cells was observed by indirect immunofluorescence test. The interaction of E2 and Daxx was analyzed by co-immunoprecipitation, Western-blot and yeast-two hybrid assay. In Caski cells the fluorescence of Daxx or PML was mainly distributed in the cytoplasm or nucleus, respectively, and in the align image their signals did not overlapped. However, when the red signal of HPV16 E2 and the green signal of Daxx in cyto- plasm of Caski cells were merged, the yellow signals appeared. The yeast co-transformed with pGBKT7/Daxx and pGADT7/E2 or pGADT7/E2 TAD can grow onto SD/-Trp-Leu-His and SD/-Trp-Leu-His-Ade plates. So Daxx wasn't co-located with PML but with HPV16 E2 mainly in the cytoplasm of Caski cells. On the base of the results one can propose that HPV16 E2, in particularly its transcription-activity domain (TAD), interacts with Daxx.

Local tissue properties of human osteoarthritic cartilage correlate with magnetic resonance T(1) rho relaxation times

The objective of this study is to examine the local relationship between T(1ρ) relaxation times and the mechanical behavior of human osteoarthritic articular cartilage using high-resolution magnetic resonance imaging (MRI) and local in situ microindentation. Seven human tibial plateaus were obtained from patients who underwent total knee arthroplasty due to severe osteoarthritis (OA). Three to six sites were selected from each sample for visual classification using the ICRS Outerbridge scale (a total of 36 sites). Samples were imaged by MR, and the local distribution of T(1ρ) relaxation times were obtained at these selected sites. The elastic and viscoelastic characteristics of the tissue were quantified nondestructively using dynamic microindentation to measure peak dynamic modulus, energy dissipation, and phase angle. Measured Outerbridge scores, MR T(1ρ) relaxation times, and mechanical properties were highly heterogeneous across each cartilage surface. Site-specific measures of T(1ρ) relaxation times correlated significantly with the phase angle (p < 0.001; R = 0.908), a viscoelastic mechanical behavior of the cartilage. The novel combination of high-resolution MR imaging and microindentation allows the investigation of the local relationship between quantitative MRI and biomechanical properties in highly heterogeneous OA cartilage. These findings suggest that MRI T(1ρ) can provide a functional assessment of articular cartilage.

The relative contributions of non-enzymatic glycation and cortical porosity on the fracture toughness of aging bone

The risk of fracture increases with age due to the decline of bone mass and bone quality. One of the age-related changes in bone quality occurs through the formation and accumulation of advanced glycation end-products (AGEs) due to non-enzymatic glycation (NEG). However as a number of other changes including increased porosity occur with age and affect bone fragility, the relative contribution of AGEs on the fracture resistance of aging bone is unknown. Using a high-resolution nonlinear finite element model that incorporate cohesive elements and micro-computed tomography-based 3d meshes, we investigated the contribution of AGEs and cortical porosity on the fracture toughness of human bone. The results show that NEG caused a 52% reduction in propagation fracture toughness (R-curve slope). The combined effects of porosity and AGEs resulted in an 88% reduction in propagation toughness. These findings are consistent with previous experimental results. The model captured the age-related changes in the R-curve toughening by incorporating bone quantity and bone quality changes, and these simulations demonstrate the ability of the cohesive models to account for the irreversible dynamic crack growth processes affected by the changes in post-yield material behavior. By decoupling the matrix-level effects due to NEG and intracortical porosity, we are able to directly determine the effects of NEG on fracture toughness. The outcome of this study suggests that it may be important to include the age-related changes in the material level properties by using finite element analysis towards the prediction of fracture risk.

The effect of dichloroacetate on health- and lifespan in C. elegans

Aging is associated with increased vulnerability to chronic, degenerative diseases and death. Strategies for promoting healthspan without necessarily affecting lifespan or aging rate have gained much interest. The mitochondrial free radical theory of aging suggests that mitochondria and, in particular, age-dependent mitochondrial decline play a central role in aging, making compounds that affect mitochondrial function a possible strategy for the modulation of healthspan and possibly the aging rate. Here we tested such a "metabolic tuning" approach in nematodes using the mitochondrial modulator dichloroacetate (DCA). We explored DCA as a proof-of-principle compound to alter mitochondrial parameters in wild-type animals and tested whether this approach is suitable for reducing reactive oxygen species (ROS) production and for improving organismal health- and lifespan. In parallel, we addressed the potential problem of operator bias by running both unblinded and blinded lifespan studies. We found that DCA treatment (1) increased ATP levels without elevating oxidative protein damage and (2) reduced ROS production in adult C. elegans. DCA treatment also significantly prolonged nematode health- and lifespan, but did not strongly impact mortality doubling time. Operator blinding resulted in considerably smaller lifespan-extending effects of DCA. Our data illustrate the promise of a "metabolic tuning" intervention strategy, emphasize the importance of mitochondria in nematode aging and highlight operator bias as a potential confounder in lifespan studies.

Changes in non-enzymatic glycation and its association with altered mechanical properties following 1-year treatment with risedronate or alendronate

SUMMARY

One year of high-dose bisphosphonate (BPs) therapy in dogs allowed the increased accumulation of advanced glycation end-products (AGEs) and reduced postyield work-to-fracture of the cortical bone matrix. The increased accumulation of AGEs in these tissues may help explain altered bone matrix quality due to the administration of BPs in animal models

INTRODUCTION

Non-enzymatic glycation (NEG) is a posttranslational modification of the organic matrix that results in the formation of advanced glycation end-products (AGEs). In bone, the accumulation of AGEs play an important role in determining fracture resistance, and elevated levels of AGEs have been shown to adversely affect the bone's propensity to brittle fracture. It was thus hypothesized that the suppression of tissue turnover in cortical bone due to the administration of bisphosphonates would cause increased accumulation of AGEs and result in a more brittle bone matrix.

METHODS

Using a canine animal model (n = 12), we administered daily doses of a saline vehicle (VEH), alendronate (ALN 0.20, 1.00 mg/kg) or risedronate (RIS 0.10, 0.50 mg/kg). After a 1-year treatment, the mechanical properties, intracortical bone turnover, and the degree of nonenzymatic cross-linking of the organic matrix were measured from the tibial cortical bone tissue of these animals.

RESULTS

There was a significant accumulation of AGEs at high treatment doses (+49 to + 86%; p < 0.001), but not at doses equivalent to those used for the treatment of postmenopausal osteoporosis, compared to vehicle. Likewise, postyield work-to-fracture of the tissue was significantly reduced at these high doses (-28% to -51%; p < 0.001) compared to VEH. AGE accumulation inversely correlated with postyield work-to-fracture (r (2) = 0.45; p < 0.001), suggesting that increased AGEs may contribute to a more brittle bone matrix.

CONCLUSION

High doses of bisphosphonates result in the accumulation of AGEs and a reduction in energy absorption of cortical bone. The increased accumulation of AGEs in these tissues may help explain altered bone matrix quality due to the administration of BPs in animal models.

Changes in Nutritional, Functional Status and Quality of Life of COPD Out-patients after a Pulmonary Rehabilitation Programme in HUKM: a Pilot Study

This quasi-experimental study was carried out to evaluate the effectiveness of an eight-week multi-disciplinary pulmonary rehabilitation programme in improving nutritional and functional status and quality of life of COPD out patients at Hospital Universiti Kebangsaan Malaysia. A total of 9 COPD outpatients aged 40 years and above (6 men and 3 women) completed at least 50% of 16 sessions of an eight-week pulmonary rehabilitation programme. Their nutritional and functional status and rating of quality of life were measured at baseline (0 day) and after 8 weeks and these were compared to those of the control group matched for age, comprising 13 subjects (11 men and 2 women). Nutritional status was determined using anthropometry, body composition (Bioelectrical Impedance Analysis) and three-day food record. Assessment of appetite for food was also carried out using the Simplified Nutritional Assessment Questionnaire (SNAQ). Functional status was assessed using the Pulmonary Functional Status and Dyspnea Questionnaire-modified version(PFSDQ-M). The handgrip strength was also measured using handgrip dynamometer. The SF36 questionnaire was used to measure the quality of life of the subjects. There was a reduction in dyspnea (-49.0%, p<0.05) and fatigue (-47.8%, p<0.05) in men after the intervention programme, as compared to their controls (dyspnea -2.9% and fatigue 8.9%). Quality of life in this group was also significantly improved by 31.8% (p<0.05) as compared to their controls (-3.0%,p>0.05). Similar trends were noted for the women, although the difference was not significant. No significant changes were seen in nutritional status assessed by anthropometry, dietary intake and appetite. However, there was a trend of increased nutrient intake and SNAQ score in the intervention group as compared to control. An eight-week pulmonary rehabilitation programme was effective in improving the functional status particularly in men, by reducing dyspnea and fatigue; and also improving their quality of life, but was not effective in changing the nutritional status.

A non-invasive in vitro technique for the three-dimensional quantification of microdamage in trabecular bone

An accurate analysis and quantification of microdamage is critical to understand how microdamage affects the mechanics and biology of bone fragility. In this study we demonstrate the development and validation of a novel in vitro micro-computed tomography (microCT) method that employs lead-uranyl acetate as a radio-opaque contrast agent for automated quantification of microdamage in trabecular bone. Human trabecular bone cores were extracted from the femoral neck, scanned via microCT, loaded in unconfined compression to a range of apparent strains (0.5% to 2.25%), stained in lead-uranyl acetate, and subsequently re-scanned via microCT. An investigation of the regions containing microdamage using the backscatter mode of a scanning electron microscope (BSEM) showed that the lead-uranyl sulfide complex was an effective contrast agent for microdamage in bone. Damaged volume fraction (DV/BV), as determined by microCT, increased exponentially with respect to applied strains and proportionately to mechanically determined modulus reduction (p<0.001). Furthermore, the formation of microdamage was observed to occur before any apparent stiffness loss, suggesting that the localized tissue yielding occurs prior to the structural yielding of trabecular bone. This non-invasive in vitro technique for the detection of microdamage using microCT may serve as a valuable complement to existing morphometric analyses of bone.

Parallelisation and application of a multi-layer atmospheric transport model to quantify dispersion and deposition of ammonia over the British Isles

An atmospheric transport model, FRAME (Fine Resolution AMmonia Exchange), has been used to model the spatial pattern of ammonia concentrations and deposition over the British Isles for the first time. The model uses a multi-layer approach with diffusion through 33 layers to describe vertical concentration profiles in the atmosphere explicitly. Together with the necessary description of atmospheric reactions with sulphur and oxidised nitrogen, this imposes a major computational requirement, with the model having a run-time of 8.5 days on a mid-range workstation. Improvement in the model run-time was sought by developing a parallel implementation coded in a data-parallel approach using High Performance Fortran. Running the code on a Cray T3E with 128 processors provided a speedup by a factor of 69. The code's portability, its validation with measurements and new maps of its application to the British Isles, are presented. Good agreement is found with measured NH3 concentrations, while wet de-position is underestimated. In addition to model uncertainties, this may be due to an underestimation of the NH3 emissions input data.

[Applying photocclusion method to study occlusion mechanics on wedge shaped teeth defect with computer assisting]

OBJECTIVE

Study the occlusal force of wedge shaped teeth defect and its relation with the clinical condition.

METHODS

Use the method of clinical examination and plaster model measurement to decide the parameters of axial gradient degree of the teeth, abrasion index, missing teeth number and so on; Adopt the computer image processing technology and program to analyse the photocclusion sheet, take the date and image information of occlusion force, areas, and occlusal stress of wedge shaped teeth defect.

RESULTS

The occlusion contact data and graph of wedge-shaped teeth defect had the features of trauma occlusion. 42.97% of them has the larger axial gradient degree, 96.09% of them has abration in different classes, 46.29% missing the front teeth and 57.03% missing the buccal teeth. Occlusal contact force increase took up 78.91% in the wedge shaped teeth defect.

CONCLUSION

It can be concluded that the not uniformly distributed occlusal force produced from the larger axial gradient degree, the defect of dentition, and the abrasion of teeth, may be the important factors which cause wedge shaped teeth defect.

Synthesis and diversity analysis of lead discovery piperazine-2-carboxamide libraries

A Lead Discovery Library of piperazine-2-carboxamide derivatives was produced for general screening. This paper discloses two novel solid phase synthetic routes used to produce 15,000 single compounds via the Irori directed sorting technique. Computational methods such as reagent clustering and library profiling were used to maximize reagent diversity and optimize pharmacokinetic parameters. The results of a four center pharmacophore analysis revealed the added diversity gained by using two independent synthetic routes.

Solid-phase synthesis of an arylsulfone hydroxamate library

Synthesis of an arylsulfone hydroxamate lead optimization library is presented. Biological activity of representative examples is given to demonstrate the value of this approach for lead optimization.

Interpreter services in healthcare. Policy recommendations for healthcare agencies

The author discusses the need for interpreter services for delivering effective healthcare in a country such as Canada, which is made up of people from diverse ethnocultural and linguistic backgrounds. As well as examining the complexity of allocation decisions and policy implementation, the author proposes policy recommendations for healthcare agencies to set up an integrated system of interpreter services based on cost-effective and equitable use of finite resources and partnership between agencies.

Human agency and the process of healing: lessons learned from women living with a chronic illness--'re-writing the expert'

In this paper we examine the notion of human agency in the context of women experiencing a chronic illness. Based on two qualitative studies conducted with Canadian women of Chinese- and Anglo-descent living with diabetes, we unmask the complex power relations inherent in patient-practitioner interactions, and problematize the privileging of healthcare providers as knowers and experts on the patient's body. Specifically, we analyse the meanings that women ascribe to their illness experience. We discuss how women experience the loss of agency in healthcare encounters, how they resist patienthood by reclaiming agency, and how healthcare providers foster agency in their interactions with women. Rather than suggesting that biomedical experts should be 'written out', we propose to rewrite healthcare providers as 'reflexive practitioners' through the construction of transformative knowledge. We argue that praxis-oriented practice, which is based on transformative knowledge, will provide the space for women and healthcare providers to enter into a new dialogue and a relation in which women can sustain a sense of self, and begin the journey of healing.

Application of evaporative light scattering detection to the characterization of combinatorial and parallel synthesis libraries for pharmaceutical drug discovery

The advent of combinatorial and parallel synthesis methodologies in drug discovery have necessitated the development of analytical techniques which permit high throughput quantitative analysis of mixtures of small organic molecules. High pressure liquid chromatography with evaporative light scattering detection has become the major tool for this task. In this article we briefly review the theory of evaporative light scattering detection and the design of commercial instruments, as well as discuss the operational constraints imposed by the exigency of analyzing en masse the product libraries generated by these new drug discovery methods. The application of evaporative light scattering detection to library analysis is illustrated using examples from our library synthesis program. Complemented by ultraviolet absorbance detection for purity assessment and mass spectrometry for product identification, evaporative light scattering detection is the only technique affording sufficient accuracy and sensitivity for high throughput library analysis.

Degradation pathways of salmon calcitonin in aqueous solution

Salmon calcitonin (sCT), a 32-amino-acid peptide, is the active component in many pharmaceuticals used for the management of bone diseases. The degradation pathways of sCT were determined, and the structures of the major degradation products were identified. Aqueous solutions of sCT at pH values of 3, 4, 5, and 6 were degraded, and the major degradation products were detected using reversed phase and size-exclusion high-performance liquid chromatography (HPLC). The degradation rate and pathways of sCT are strongly dependent on pH in the pH range between 3 and 6. The major degradation products were isolated by semipreparative HPLC and identified using a variety of spectroscopic and bioanalytical techniques. The results show that sCT can undergo hydrolyses resulting in cleavage of the 1-2 amide bond and deamidation of the Gln14 and Gln20 residues, sulfide exchange that leads to an unusual trisulfide derivative, and dimerization to reducible and nonreducible dimers. The mechanisms for the pathways can be rationalized from known degradation pathways of peptide and proteins.

[Clinical application of inspiring psychological nursing in vaginal delivery]

A new nursing method named Inspiring Psychological Nursing was initiated and applied to 176 primigravida undergoing vaginal delivery from Jan. to Jun. 1994. 202 primigravida who received general medical care during vaginal delivery from Jan. to Jun. 1993 was served as control group. No significant differences were found between the two groups regarding to age, gestational weeks, times of pregnancy, fetal position and newborn's weight. However significant differences were found regarding the duration of the second stage of labor and incidence of newborn asphyxia. Primigravida in the control group usually delivered after 60 min. and carried a higher incidence of newborn asphyxia, being 6.7%. It's concluded that Inspiring Psychological Nursing could significantly improve pregnancy outcome.

Enzyme inhibition during the conversion of squalene to cholesterol

Two separate enzymatic assays were developed in order to test the selectivity of inhibitors in cholesterol biosynthesis. One assay detects inhibition of delta 5.7-sterol delta 7-reductase, the enzyme involved in the conversion of 7-dehydrocholesterol to cholesterol. Delta 5.7-Sterol delta 7-reductase was inhibited by both RPR 101821, a protonated cyclohexylamine, and BM 15.766, a piperazine derivative, with IC50 values of 1 microM. The second assay detects accumulation of any of five intermediates (squalene oxide, squalene dioxide, lanosterol, desmosterol, and 7-dehydrocholesterol) upon inhibition of enzymes catalyzing reactions in the conversion of squalene to cholesterol. In this assay, inhibition data were most accurate when control assays exhibited a conversion of squalene to cholesterol in the order of 50%. The time required to attain 50% conversion of squalene to cholesterol was 6 h. Given a high inhibitor to substrate concentration ratio and the possible values of Ki, kon, and koff for the reaction between enzymes and inhibitor to form enzyme-inhibitor complexes, it was predicted that in the presence of inhibitors, intermediate accumulation could still be observed after 6 h incubation. The experimental results were in agreement with this prediction.

Primary structure control of recombinant proteins using high-performance liquid chromatography, mass spectrometry and microsequencing

The conformity of two recombinant proteins (a von Willbrand factor fragment and human serum albumin, consisting of respectively 289 and 585 amino acids) has been examined by HPLC combined with mass spectrometry and microsequencing, on both intact material and fragment peptides obtained by proteolytic cleavage. These studies confirmed that the primary structure of the recombinant proteins corresponds to that predicted from their gene, particularly the integrity of their N and C termini, and, in the case of albumin, the agreement between the observed disulfide bond pattern and the published model. Furthermore, the structure of an albumin-related compound could be elucidated. Application of LC-MS for batch-to-batch quality control is also under discussion.

Thiamin requirement of juvenile shrimp (Penaeus monodon)

In a 9-wk feeding trial, juvenile shrimp (Penaeus monodon) were fed semipurified diets containing seven levels (0, 20, 40, 60, 80, 160 and 320 mg/kg diet) of supplemental thiamin hydrochloride. The dietary thiamin level required for optimal growth in P. monodon was found to be approximately 14 mg/kg diet based on hemolymph (blood) thiamin analysis. The minimum dietary thiamin level that produced substantial shrimp growth was approximately 13 mg/kg diet. Shrimp fed unsupplemented diets (thiamin content of 0.12 mg/kg diet) did not demonstrate specific deficiency signs, except those universal signs such as retarded growth, poor food conversion and low survival rates.

Analysis of duodenal bile acids by high performance liquid chromatography in infants with cholestasis

Non-sulfated bile acid levels including cholic acid (CA), chenodeoxycholic acid (CDCA), deoxycholic acid (DCA), lithocholic acid (LCA), ursodeoxycholic acid (UDCA), five taurine conjugates, and five glycine conjugates in duodenal juice were measured in 50 Chinese infants with cholestasis to test their diagnostic value. All 17 with biliary atresia (BA) cases, 11 out of 26 neonatal hepatitis (NH) cases and one case with paucity of the interlobular bile duct were without detectable bile acids. In those NH patients with detectable bile acids, the major components were conjugated forms of CA and CDCA, which was similar to all 6 cases of the comparison group with other diseases. The minor bile acid components identified in them were glycine conjugated UDCA, free CDCA, free CA, and free and conjugated DCA. Only one patient with NH had taurine conjugated LCA. The mean total duodenal bile acid level in 15 patients with NH was significantly lower than that in the 6 patients of the comparison group. Most patients with NH had a CDCA/CA ratio of less than one, indicating that cholic acid is the predominant form in their bile. Glycine conjugated bile acids were the predominant bile acids present in 11 out of 15 patients with NH and 4 out of 6 of the comparison group patients. The results suggest that the detection of duodenal bile acids by a sensitive HPLC method is of limited value in making a differential diagnosis between BA and NH.(ABSTRACT TRUNCATED AT 250 WORDS)