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Hydroxyapatite-supported Ag-TiO2 as Escherichia coli disinfection photocatalyst.

A series of hydroxyapatite (HAP), 1wt% Ag-TiO(2) (AT1), 1wt% Ag-HAP and 5wt% AT1/HAP composite catalysts were prepared by incipient wetness and mechanical mixing methods. They were characterized by X-ray diffraction (XRD), FT-IR, SEM and ESCA analyses and their photocatalytic bactericidal activities were measured in suspension using Escherichia coli (E. coli), a water pollutant indicator. The surface analysis revealed that the Ag/Ti ratio is found to be ca. 0.0273 and also it indicated that the titania is present in the form of Ti(4+) and Ag is present as metallic silver. Both the XRD and ESCA analyses confirmed the phase of metallic Ag particles, which played a significant role on the bactericidal activity of the Ag doped TiO(2) catalysts. The FT-IR analysis of HAP revealed that the peak intensity is due to the absorbance of surface PO(4)(3-) group centered at wave number 1030cm(-1) and is drastically decreased upon exposure to UV for 1h. The HAP displayed high amount of bacteria adsorption, ca. 80% during the dark experiments compared to other catalytic systems tested. The cumulative photocatalytic properties of AT1/HAP catalytic system resulted in 100% E. coli bacteria reduction within 2min.

Adsorption↗

Racial/ethnic disparities in the treatment of epilepsy: what do we know? What do we need to know?

We examine current understanding of the minority disadvantage in the clinical management of epilepsy. We performed an online literature search using several keywords (race, ethnicity, epilepsy, treatment, and quality of life) and identified additional literature through cross-referencing/manual search. The search produced 58 items published between 1977 and 2005. Of 49 original research studies, 38 were quantitative, 7 were qualitative, and 4 used mixed methods. Three or more articles were published in Epilepsia, Epilepsy &Behavior, Epilepsy Research, Neurology, and Seizure. Research concerning racial/ethnic differences in epilepsy treatment is scarce and limited by methodology, but suggests underutilization of state-of-the-art therapies by minorities. Racial/ethnic minorities also appear to have limited knowledge about epilepsy and its treatment, experience barriers to care, lack social support, and seek alternative therapies for epilepsy. We propose a framework to identify the array of disparities, points of intervention, and interventions.

Attitude to Health↗

Sealing effect of rapidly curable gelatin-poly (L-glutamic acid) hydrogel glue on lung air leak.

BACKGROUND: Air leak is a problem commonly occurring in lung and thoracic operations. In this study, a rapidly curable hydrogel glue was prepared as the seal for lung air leak. METHODS: Mixing an aqueous solution of gelatin and poly(L-glutamic acid) with a water-soluble carbodiimide produced a hydrogel. The sealing effect on the air leak wound of rat lung was compared with that of conventional fibrin glue. RESULTS: The gelatin-poly(L-glutamic acid) hydrogel glue was solidified as rapidly as the fibrin glue, and was significantly more effective in sealing the lung air leak than the fibrin glue. Approximately 80% of the lungs treated with the hydrogel glue exhibited no air leak at the lung pressure of 50 cm H2O. Urea addition could prevent spontaneous gelatination of the mixed solution at room temperature and did not affect the hydrogel sealing effect. The bonding strength of the hydrogel glue both with and without urea to the lung tissue was significantly higher than that of the fibrin glue. CONCLUSIONS: We concluded that this strong lung adhesion of the gelatin-poly(L-glutamic acid) hydrogel glue resulted in its superior sealing effect.

Animals↗

Small-angle neutron scattering study of the lipid bilayer thickness in unilamellar dioleoylphosphatidylcholine vesicles prepared by the cholate dilution method: n-decane effect.

Previous X-ray diffraction studies on fully hydrated fluid lamellar egg phosphatidylcholine phases indicated a approximately 10 A increase of bilayer thickness in the presence of excess n-decane [Biochim. Biophys. Acta 597 (1980) 455], while the small-angle neutron scattering (SANS) on unilamellar extruded dioleoylphosphatidylcholine (DOPC) vesicles detected substantially smaller 2.4+/-1.3 A bilayer thickness increase at n-decane/DOPC molar ratio of 1.2 [Biophys. Chem. 88 (2000) 165]. The purpose of the present study is to investigate the n-decane effect on the bilayer thickness in unilamellar DOPC vesicles prepared by the sodium cholate (NaChol) dilution method. Mixed DOPC+NaChol micelles at DOPC and NaChol concentrations of 0.1 mol/l were prepared in 2H(2)O containing 0.135 mol/l NaCl. This micellar solution was diluted in 0.135 mol/l NaCl in 2H(2)O to reach the final DOPC and NaChol concentrations of 0.008 mol/l. Thirty microliters of n-decane solution in methanol was added to 1 ml of this dispersion. After methanol evaporation, SANS was conducted on the dispersions. From the Kratky-Porod plot ln[I(Q)Q(2)] vs. Q(2) of SANS intensity I(Q) in the range of scattering vector values Q corresponding to interval 0.001 A(-2)<or=Q(2)<or=0.006 A(-2), the bilayer radius of gyration R(g) and the bilayer thickness parameter d(g)=12(0.5)R(g) were obtained. The values of d(g) indicate that the bilayer thickness increases by 2.4+/-0.9 A up to n-decane/DOPC molar ratio of 1.6. This result confirms the previous SANS findings obtained with extruded vesicles.

Alkanes↗

Fluorescence measurements of fusion between human erythrocytes induced by poly(ethylene glycol).

The kinetics of poly(ethylene glycol) (PEG)-induced fusion between intact human erythrocytes was continuously monitored by a fluorescence lipid mixing method, utilizing the dequenching of the fluorescence probe, 1-oleoyl-2-[12-[(7-nitro-2,1,3-benzoxadiazol-4-yl)amino]dodecanoyl ] phosphatidylcholine (C12-NBD-PC). The steady-state fluorescence intensity was detected from the surface of cells in a monolayer on an alcian blue-coated glass coverslip. The relief of fluorescence self-quenching after fusion between C12-NBD-PC labeled and unlabeled intact erythrocytes was measured. The extent of fluorescence dequenching was normalized based on the measured concentration of probes in membranes, the projected partial dequenching due both to dilution by intercellular fusion, and the dilution between the inner and outer leaflets of membranes (flip-flop). There was no significant increase in fluorescence intensity during PEG treatment of 5 min, at 4 degrees C. Intensity increased immediately after the dilution of PEG, and reached saturation in 30 min. The efficiency of fusion increased with the increasing of PEG concentrations. Only 4% enhancement of saturated relative fluorescence intensity was detected in 25 wt% PEG-induced cell fusion; 23% enhancement in 30 wt%; and 66% enhancement in 35 wt%. The transfer of fluorescent probes between membrane bilayer leaflets (flip-flop) was also monitored during the fusion process. Flip-flop was monitored in confluent monolayers as well as in isolated cells. There was no significant spontaneous flip-flop within 30 min of dilution. The relative fluorescence intensity enhancement contributed by the dilution of probes between fused labeled and unlabeled cells (at a 1:1 ratio) was found to account for only 39% of the observed final dequenching, whereas the contribution by flip-flop associated with cell fusion was found to account for 9%, and flip-flop without fusion contributed approximately 18%. A portion of the flip-flop is a consequence of hemolysis. Therefore, fluorescence dequenching measurements of fusion of whole cells must be interpreted with caution.

Biophysical Phenomena↗

How important are rhyme and analogy in beginning reading?

Current debate over the influence of phonological awareness on early reading development is polarised around small-unit (phoneme) processing and large-unit (onset-rime) processing. These opposing theories were contrasted by assessing the impact of pre-school phonological skills on reading amongst children experiencing their first year of formal instruction by a mixed method. Those beginning readers who could decode nonwords were found to have accomplished this by employing their letter-sound knowledge rather than by making analogies based on familiar rime units. Children displayed this pattern of performance regardless of their pre-school rhyming skills. Further investigations revealed that explicit awareness of onset and rime units was poor, even amongst children whose implicit rhyming skills were excellent. This evidence, together with the children's knowledge of orthographic units, was consistent with the view that letter-sound correspondences rather than onset or rime units formed the basis of their first attempts to utilise phonology in reading. The findings are discussed with reference to instructional influences on early reading and phonological awareness.

Child, Preschool↗

Longitudinal analysis of pulmonary function decline in patients with cystic fibrosis.

BACKGROUND: Chronic progressive lung disease is the most prominent cause of morbidity and death in patients with cystic fibrosis (CF), but severity of lung disease and rate of lung function decline are widely variable. Accurate estimates of decline have been difficult to define and compare because the timing of measurements and duration of follow-up differ in various patient groups. PATIENTS: Three hundred sixty-six patients with CF, born from 1960 to 1974, were selected from a CF database birth cohort if they had two or more measurements of pulmonary function, at least one of which was performed before the age of 10 years. METHODS: Mixed model regression analysis provided estimates of the average rate of decline of spirometry measurements in subgroups on the basis of survival age, sex, pancreatic status, and genotype. RESULTS: Patients who died before the age of 15 years had significantly poorer pulmonary function when first tested and a more rapid decline in pulmonary function thereafter than patients who survived beyond the age of 15 years. In the latter, functional levels at the age of 5 years were normal, but average rates of decline were significantly related to survival age. Female patients had significantly steeper decline than male patients, and those with pancreatic insufficiency had much steeper decline than those with pancreatic sufficiency. In the subset of 197 who survived to 1990 and were subsequently genotyped, rate of decline was greater in those homozygous for the delta F508 mutation, compared with those who were heterozygous for delta F508 or those, who had two other mutations. DISCUSSION: All but the most severely affected patients, who died before age 15, appear to have had normal pulmonary function when first tested in early childhood. Pancreatic sufficiency, male gender, and some non-delta F508 mutations are associated with a slower rate of pulmonary function decline. Mixed model analysis is a valuable tool for describing and comparing pulmonary function decline in groups of patients with CF.

Adolescent↗

Is there a link between children's motor abilities and unintentional injuries?

PROBLEM: The common view is that clumsy children experience unintentional injury more frequently. Empirical evidence supporting this position is mixed. METHOD: One hundred 6- and 8-year-olds completed a battery of nine tasks designed to assess motor ability. Mothers completed a lifetime injury history measure about their children and families completed a 2-week injury diary assessing frequency and severity of daily injuries. RESULTS: Internal reliability for the motor ability battery was good. Correlations between motor ability measures and injury risk were nonsignificant and near zero. DISCUSSION: Motor ability does not appear to be directly related to injury risk. Possible explanations include: (a) coordinated and clumsy children engage in hazardous activities with differing frequency; or (b) other individual difference factors may interact with motor ability to explain children's injury risk. IMPACT ON INDUSTRY: Children's motor abilities do not appear to be directly linked to rate of unintentional injury, but instead may influence risk for injury in conjunction with other factors. Results could have implications to the engineering of children's toys and playground equipment and to the design of appropriate supervision strategies for children engaging in potentially dangerous activities.

Accidents↗

Incidence of Henoch-Schönlein purpura, Kawasaki disease, and rare vasculitides in children of different ethnic origins.

BACKGROUND: The frequency and ethnic variation of Henoch-Schönlein purpura, Kawasaki disease, and rarer vasculitides during childhood are not well characterised. Our aim was to ascertain the incidence and ethnic distribution of these conditions in children resident in a region of the UK with a diverse ethnic mix. METHODS: 1.1 million children younger than age 17 years live in the West Midlands. Between Sept 1, 1996, and Aug 31, 1999, we surveyed this population with monthly questionnaires sent to 321 consultants, a single questionnaire sent to 2860 family doctors, and review of 406 case notes with diagnostic codes for vasculitis. We included in the analyses children who fulfilled established criteria for vasculitis with disease onset during the study, and calculated incidence rates from population rates derived from the census of 1991. FINDINGS: We identified 586 new instances of vasculitis and connective tissue disease. The estimated annual incidence of Henoch-Schönlein purpura was 20.4 per 100000, and was highest between the ages of 4 years and 6 years (70.3 per 100000). The estimated annual incidence of Kawasaki disease was 5.5 per 100000 in children younger than 5 years, and was highest in Indian subcontinent Asian children (14.6 per 100000). Indian subcontinent Asian and black children had the highest incidence of systemic lupus erythematosus, juvenile dermatomyositis, and other primary systemic vasculitides. INTERPRETATION: Childhood Henoch-Schönlein purpura is more frequent in the West Midlands than previously reported, and Kawasaki disease has a higher incidence than previously indicated in the UK, with the highest incidence in Indian subcontinental Asian children. Other vasculitis is rare in childhood.

Adolescent↗

Trabecular bone response to surface roughened and calcium phosphate (Ca-P) coated titanium implants.

The influence of calcium phosphate (Ca-P) coating and surface roughness on the trabecular bone response of titanium implants was investigated. Four types of titanium implants, i.e. blasted with titanium powder, sintered with titanium beads, titanium powder blasted and provided with an additional Ca-P coating, and titanium beads with Ca-P coating, were prepared. The Ca-P coating was deposited by ion beam dynamic mixing method. The Ca-P coating was rapid heat-treated with infrared radiation at 700 degrees C. The implants were inserted into the trabecular bone of the left and right femoral condyles of 16 rabbits. After implantation periods of 2, 3, 4 and 12 weeks, the bone-implant interface was evaluated histologically and histomorphometrically. Histological evaluation revealed new bone formation around different implant materials after already 3 weeks of implantation. After 12 weeks, mature trabecular bone surrounded all implants. At 3 and 4 weeks of implantation, no difference existed in bone contact to the various implant materials. On the other hand, after 12 weeks of implantation the highest percentage of bone contact was found around the Ca-P coated beads implants. Supported by the results, we concluded that the combination of surface geometry and Ca-P coating benefits the implant-bone response during the healing phase.

Animals↗

Lipid solubilization in human gallbladder versus hepatic biles.

BACKGROUND/AIMS: Cholesterol crystallizes more rapidly in gallbladder than in hepatic biles, supposedly due to formation of cholesterol-supersaturated vesicles in concentrated gallbladder biles because of preferential micellization of phospholipids compared to cholesterol. We therefore aimed to compare lipid solubilization in hepatic and gallbladder biles. METHODS: Mixed micellar and vesicular phases were separated from hepatic and associated gallbladder biles of seven cholesterol gallstone patients by using state-of-the-art gel filtration with bile salts at intermixed micellar/intervesicular compositions and concentrations in the eluant. RESULTS: Vesicles were found in 6 out of 7 hepatic biles, but only in 2 of the corresponding gallbladder biles. Both percentage (7.8+/-5.1 vs. 36.3+/-7.6%; p = 0.01) and amount (0.9+/-0.2 vs. 1.7+/-0.3 mM; p = 0.06) of vesicular cholesterol were lower in gallbladder biles. Similar results were found for vesicular phospholipids (1.3+/-0.8 vs. 11.6+/-6.0%; p = 0.05; and 0.3+/-0.1 vs. 1.1+/-0.5 mM; p = 0.07). The vesicular cholesterol/ phospholipid ratio was 1.7+/-0.5 in hepatic bile but 4.3 and 1.8 in the 2 gallbladder biles which contained vesicles. Mixed micelles in gallbladder biles had a higher cholesterol saturation index than mixed micelles in hepatic biles (1.43+/-0.11 vs. 1.15+/-0.07; p = 0.02). CONCLUSIONS: Concentration of bile in the gallbladder leads to decreased vesicular lipid contents. The finding of supersaturated mixed micelles in the absence of vesicles in a significant number of patients points to the possibility of non-vesicular modes of crystallization.

Bile Ducts↗

Evaluation of a community-level health policy intervention.

In this article an evaluation approach towards an innovative community-level health policy intervention in Germany is presented. The aim of the intervention was basically to establish new structures of health planning and co-ordination at the community level in order to improve health monitoring and health care as well as health promotion. To realise this aim Round Tables, Working Groups and Project Offices were implemented in the communities. Based on the theory of change and using a developmental perspective the evaluation was focussed on the links between contexts, activities and outputs of the initiative. A mixed-method design with triangulation of quantitative and qualitative methods was applied. Results show that most of the communities succeeded in convening all major organisations and institutions of the local health care system within the Round Tables. Working climate was rated favourably by most of the involved actors. All communities succeeded in developing and enacting recommendations for action programmes, and about 40% of these programmes were implemented during the observation period of the project. Probability of programme implementation was high if measures remained within the scope of the communities' range of decision authority. Potential effects on population health produced by the action programmes could not be assessed both for logistic reasons and due to the short observation period. Finally, some major characteristics of health policy evaluation at the community level are discussed briefly.

Community Health Planning↗

An evaluation of the baccalaureate-nursing program within the (MOPH), Thailand.

This research study was designed to evaluate the baccalaureate-nursing curricula undertaken in the nursing colleges under the jurisdiction of the Ministry of Public Health (MOPH), Thailand. A stakeholder approach was used to incorporate mixed methods of data collection and models of evaluation within the research framework. Both qualitative and quantitative approaches were used. Newly registered nurses and their colleagues were generally positive about the course outcomes. However, qualitative data demonstrate a need to focus more on the development of abilities related to life-long learning and critical thinking. The findings suggest challenges in achieving program outcomes attributed to the feasibility of implementation strategies. Concepts in the curriculum plan are not fully translated into practice. A number of factors have a major impact on the actual program implementation or course organisation and teaching/learning processes. There is evidence of competing or conflicting ideologies about nursing practice and education. Findings suggest that the preferable educational models for contemporary and future nursing education are process rather than content-based. It is challenging to develop ways of accommodating the more desirable professional nursing and educational approaches within the context of Thailand and MOPH nursing education policies where resources are limited and the maintenance of Thai culture is of paramount importance.

Curriculum↗

"What do you mean 'what's wrong with her?'": stigma and the lives of families of children with disabilities.

This study extends the application of modified labeling theory to the experience of courtesy stigma in families of children with disabilities. The study utilizes a mixed methods approach that integrates quantitative analysis of survey data, qualitative analysis of interactive interviews and personal narrative. A survey of 81 mothers of children with disabilities in Florida, USA, is used to test hypotheses related to the impact of perceived stigma on emotional and social outcomes for mothers and children. The author's experience as the mother of a child with cerebral palsy and interactive interviews with seven other mothers with similar experiences are used to contextualize, humanize and help interpret the quantitative findings. Results indicate that controlling for the effects of salient maternal and child characteristics and the daily hassles of caring for a child with a disability (objective burden), maternal perceptions that individuals with disabilities are devalued and discriminated against (stigmatized) by others increases maternal distress (subjective burden). Findings also indicate that children of mothers who perceive high levels of stigma interact less frequently with age peers in the informal settings of homes and neighborhoods.

Attitude to Health↗

Preparation and dissolution characteristics of griseofulvin solid dispersions with saccharides.

To improve the solubility of poorly water-soluble drugs, we studied physical characteristics of griseofulvin (GF) solid dispersions with saccharides as the dispersion carrier using a roll mixing method. In all carriers tested, roll mixtures of GF and saccharides gradually became amorphous, and the solubility of GF increased. The solubility of GF was higher in the mixtures with higher molecular weight carriers such as corn starch and processed starch. The dissolution of GF was markedly improved by the GF-Britishgum roll mixture. The initial dissolution rate of these mixtures was 170-fold higher than GF alone. The surface tension of carrier aqueous solutions was low in the processed starch with branched sugar chains. The initial dissolution rate of GF in physical mixtures was correlated with the surface tension of carrier aqueous solutions. The stability of the amorphous state of GF at a high humidity was maintained in the mixtures with carriers with a high molecular weight. These results indicated that the solubility of GF was markedly improved in the roll mixtures. It was suggested that the saccharides with a high molecular weight are useful carriers for solid dispersions.

Chemistry, Pharmaceutical↗

Development and validation of the Ontario acute myocardial infarction mortality prediction rules.

OBJECTIVES: To develop and validate simple statistical models that can be used with hospital discharge administrative databases to predict 30-day and one-year mortality after an acute myocardial infarction (AMI). BACKGROUND: There is increasing interest in developing AMI "report cards" using population-based hospital discharge databases. However, there is a lack of simple statistical models that can be used to adjust for regional and interinstitutional differences in patient case-mix. METHODS: We used linked administrative databases on 52,616 patients having an AMI in Ontario, Canada, between 1994 and 1997 to develop logistic regression statistical models to predict 30-day and one-year mortality after an AMI. These models were subsequently validated in two external cohorts of AMI patients derived from administrative datasets from Manitoba, Canada, and California, U.S. RESULTS: The 11-variable Ontario AMI mortality prediction rules accurately predicted mortality with an area under the receiver operating characteristic (ROC) curve of 0.78 for 30-day mortality and 0.79 for one-year mortality in the Ontario dataset from which they were derived. In an independent validation dataset of 4,836 AMI patients from Manitoba, the ROC areas were 0.77 and 0.78, respectively. In a second validation dataset of 112,234 AMI patients from California, the ROC areas were 0.77 and 0.78 respectively. CONCLUSIONS: The Ontario AMI mortality prediction rules predict quite accurately 30-day and one-year mortality after an AMI in linked hospital discharge databases of AMI patients from Ontario, Manitoba and California. These models may also be useful to outcomes and quality measurement researchers in other jurisdictions.

Aged↗

Nonfatal farm injury incidence and disability to children: a systematic review.

OBJECTIVE: To summarize the literature on farm child nonfatal injury incidence and the subsequent disability to children. SEARCH STRATEGY: We used a systematic process to search the following databases: MEDLINE, EMBASE, ERIC, NTIS and NIOSHTIC. The reference lists from each potentially eligible study were checked and experts in the field contacted for additional reports. SELECTION CRITERIA: Studies for selection had to meet the following criteria: published in the last 20 years (1979-1998); located in North America; and include nonfatal farm injury cases for children under age 20. DATA COLLECTION AND ANALYSIS: Thirty-two studies met the inclusion criteria and were examined for study design, location, sample size, injury rate, injury sources, and functional outcomes. RESULTS: Among the 32 studies, there were 9 case series, 11 secondary analyses of administrative databases, 2 case-control studies, 6 cross-sectional surveys, one mixed-method study, 2 prospective case series reports, and 1 cohort study. Twenty-two of the studies confined the sample to agriculture, but nine of these combined children within a larger sample, creating considerable difficulty in examining only agricultural injuries to children. Only one study focused on outcome measurement. Although nearly all the reports provided some discussion about injury severity, these comments were generally limited to injury severity scores or injury type. CONCLUSIONS: Despite increasing attention on farm-related child injury, the literature continues to report primarily descriptive studies that rely on small samples focusing on the nature of the injury event and immediate consequences. Analysis of larger databases, such as worker compensation claims, trauma registries, and agricultural injury surveillance, still lacks valid denominators; thus, incidence rates cannot be calculated. Very little was found regarding disability among children who experienced agricultural injury, even though the literature clearly proclaims the severity and seriousness of child injury on farms. To complete the portrait of the burden of this continuing problem, research must include functional outcome measures.

Adolescent↗

Dopaminergic characteristics of isolated parietal cells from rats.

Recently we have identified a dopamine-producing system in the gastric mucosa of rats. All the available morphological data suggest that parietal cells synthesize dopamine. In the present study we investigated the dopaminergic characteristics of isolated parietal cells by different methods. Mixed gastric mucosal cells were isolated and size-fractionated by elutriation. The proportion of neurons, parietal and endocrine cells in the fractions were determined by immunocytochemistry (ICC) using antibodies to neurofilament, proton pump and chromogranin A, respectively. No neurons were found in any of the cell preparations, while 56% parietal cell and 0.0% endocrine cell were achieved in the parietally enriched fraction. By Western blot, a tyrosine hydroxylase (TH, the rate-limiting enzyme of the catecholamine synthesis) immunoreactive protein species was demonstrated in isolated mucosal cells, comigrating with the TH immunoreactivity from PC12 cells. The TH immunoreactivity was colocalized to parietal cells by ICC. Dopamine transporter (DAT), a regulator of extracellular/intracellular dopamine balance in the nervous system, was also demonstrated in parietal cells. A significant amount of dopamine and DOPA were measured by HPLC (13.4 and 9.57 pg/10(6) cell, respectively) in parietally enriched cell fraction. Since this enriched cell fraction was virtually clear of both neurons and endocrine cells, demonstration of TH enzyme, DAT and dopamine in this fraction confirms that the parietal cell population might be a major source of dopamine in the rat stomach, supporting our previous results achieved using whole tissue samples.

Animals↗