1039 RECEIVING ASSISTANCE FROM DOMESTIC ROBOTS: WHAT ARE ELDERS’ PREFERENCES?

Introduction

Aging leads to decline in physical and functional ability. Strengthening the domestic support enables elders to manage their health and living at home and reduce their need for residential service. Domestic robots can potentially provide a broad range of support to the elders. However, relatively little research attention has investigated elders’ preferences on it. This study aims to investigate elders’ preferences on receiving assistance from domestic robots.

Methods

This cross-sectional descriptive study recruited a convenient sample of 365 robotic inexperienced elders (65-99 years old). It used the Assistance Preference Checklist to assess participants’ preferences on receiving assistance from domestic robots in 48 home-based tasks under six aspects including personal care, leisure activities, health assistance, chores, information management, and manipulating objects. It used t-test and one-way analysis of variance to compare the difference in preferences between participants with different demographic and health characteristics.

Results

Overall, participants preferred domestic robots to assist in tasks under the aspect on chores, information management, and manipulating objects. Specifically, males indicated a higher preference for domestic robots to assist in maintaining lawn or raking leaves than females (p = 0.05). Married participants indicated a higher preference for domestic robots to assist in getting information on weather/news than unmarried participants (p = 0.049). In contrast, participants who were partially dependent and fully dependent indicated a higher preference for domestic robots to assist in tasks under the personal care aspect such as shaving, bathing, washing/combing hair, getting dressed, walking, and brushing teeth (p < 0.001), comparing to participants who were physically independent.

Conclusion

This study provides insight for manufacturers to develop domestic robots with specific capabilities which are important to support elders’ living in the community. Moreover, it helps the care providers to identify domestic robots with the required capabilities that meet elders’ specific preferences.

1040 VALIDATION OF THE CHINESE VERSION OF THE ASSISTANCE PREFERENCE CHECKLIST

Introduction

Domestic robots have great potential to be developed as a useful and supportive device for elders in domestic setting. To achieve the intended purpose, the designs of domestic robots should make reference to elders’ preferences. The Assistance Preference Checklist is developed to assess elders’ preferences on receiving assistance from domestic robots. It comprises of 48 home-based task under six categories including personal care, leisure activities, health assistance, chores, information management, and manipulating objects. Altogether, these tasks are considered important for the elders to fulfil their general health needs and maintain their homes. The Assistance Preference Checklist is valid and reliable. To adapt it in the Chinese population, the Assistance Preference Checklist has been translated from English to Chinese according to the standard translation model. This study aims to validate the Chinese version of the Assistance Preference Checklist (the checklist).

Method

This was a validation study. Semantic and content equivalence of the checklist was evaluated by an expert panel (five academic specialized on instrument validation or translation and 15 nurses specialized on geriatrics). Content validity of the checklist was assessed by another expert panel (one academic specialized on instrument validation and two nurses specialized on geriatrics). Internal consistency of the checklist was determined by Cronbach's method on a convenience sample of 50 Chinese-speaking elders in Hong Kong.

Results

The checklist demonstrated good semantic and content equivalence with the original English version. The experts agreed that it was appropriately translated. The checklist demonstrated good content validity by having a content validity index of 1.00. Additionally, the checklist reported satisfactory internal consistency by having a Cronbach's alpha of 0.95.

Conclusion

The Chinese version of the Assistance Preference Checklist is a useful instrument for assessing elders’ preferences on receiving assistance from domestic robots. Findings provide evidence on its validity and reliability.

1047 VALIDATION OF THE CHINESE VERSION OF THE KATZ INDEX OF INDEPENDENCE IN ACTIVITIES OF DAILY LIVING

Introduction

Among the instruments that measure an elder’s functional dependence level, the Katz Index of Independence in Activities of Daily Living has the advantages of being neutral, easy to use, valid, and reliable. It is a six-item instrument rating an elder’s functional dependence level in performing activities of daily living, including bathing, dressing, toileting, transferring, continence, and feeding. Each item can be rated nominally as 1 (does not require assistance to finish the activity) or 0 (requires assistance to finish the activity). By summing the score of the six items, the functional dependence level of an elder can be classified as independent (6 points), partially dependent (3–5 points), or dependent (< 2 points). The instrument has been translated from English to Chinese through forward and backward translation. This study aims to validate the Chinese version of the Katz Index of Independence in Activities of Daily Living (Katz ADL-Chinese).

Method

This was a validation study. The Katz ADL-Chinese was examined by an expert panel (one academic specialized on instrument validation, four academic specialized on translation, fifteen nurses specialized on geriatrics) for its semantic and content equivalence with the original English version. It was evaluated by another expert panel (one academic specialized on instrument validation and two nurses specialized on geriatrics) for its content validity. Moreover, it was tested and re-tested at 1-week interval on 30 Chinese-speaking elders in Hong Kong.

Results

Good result was achieved on the testing for semantic and content equivalence. All experts confirmed that the Katz ADL-Chinese was appropriately translated. Good content validity was observed. The context validity index at item-level and scale-level was 1.00, respectively. Good stability was observed as well. The test–retest reliability coefficient was 0.85.

Long-term exposure of K562 cells to benzene metabolites inhibited erythroid differentiation and elevated methylation in erythroid specific genes

Benzene is a common occupational hazard and a widespread environmental pollutant. Previous studies have revealed that 72 h exposure to benzene metabolites inhibited hemin-induced erythroid differentiation of K562 cells accompanied with elevated methylation in erythroid specific genes. However, little is known about the effects of long-term and low-dose benzene metabolite exposure. In this study, to elucidate the effects of long-term benzene metabolite exposure on erythroid differentiation, K562 cells were treated with low-concentration phenol, hydroquinone and 1,2,4-benzenetriol for at least 3 weeks. After exposure of K562 cells to benzene metabolites, hemin-induced hemoglobin synthesis declined in a concentration- and time-dependent manner, and the hemin-induced expressions of α-, β- and γ-globin genes and heme synthesis enzyme porphobilinogen deaminase were significantly suppressed. Furthermore, when K562 cells were continuously cultured without benzene metabolites for another 20 days after exposure to benzene metabolites for 4 weeks, the decreased erythroid differentiation capabilities still remained stable in hydroquinone- and 1,2,4-benzenetriol-exposed cells, but showed a slow increase in phenol-exposed K562 cells. In addition, methyltransferase inhibitor 5-aza-2'-deoxycytidine significantly blocked benzene metabolites inhibiting hemoglobin synthesis and expression of erythroid genes. Quantitative MassARRAY methylation analysis also confirmed that the exposure to benzene metabolites increased DNA methylation levels at several CpG sites in several erythroid-specific genes and their far-upstream regulatory elements. These results demonstrated that long-term and low-dose exposure to benzene metabolites inhibited the hemin-induced erythroid differentiation of K562 cells, in which DNA methylation played a role through the suppression of erythroid specific genes.

Determination of molecular weight profile for a bioactive β-(1→3) polysaccharides (Curdlan)

This paper focuses on the development of methodology based on MALDI-TOF mass spectrometry for evaluation of molecular weight profile of the water-insoluble portion of an extracellular polysaccharide, i.e. Curdlan. As previously demonstrated, MALDI analysis of water-insoluble Curdlan fraction gave number-average (M(n)) and weight-average (M(w)) molecular weights of 8000 and 8700 Da, respectively [T.W.D. Chan, K.Y. Tang, Rapid Commun. Mass Spectrom. 17 (2003) 887]. To validate the MALDI determined molecular weight information, several additional analytical schemes were used to analysis the water-insoluble Curdlan fraction. In all cases, the water-insoluble Curdlan sample was fractionated by gel permeation chromatography (GPC) using Sephadex G-75 column. The M (n) of low-mass and narrow distributed polysaccharide fractions were obtained by MALDI-MS. Good linearity was found in the calibration plot constructed from the measured M (n)-values and the corresponding elution time/volume. The relative quantity of various fractionated samples was then measured using three different approaches. These include (a) direct refractometric analysis; (b) UV-vis absorption analysis of the Aniline Blue stained sample; and (c) GC-MS analysis of the hydrolyzed and TMS-derivatized sample. Using results obtained from theses quantification methods and the correlation function between the GPC retention time and M (n), the MW and MWD of water-insoluble Curdlan were obtained. Our results demonstrated that the previous use of MALDI methods for measuring M(n), M(w) and polydispersity (PD) of water-insoluble Curdlan (with and without GPC fractionation) were unreliable. However, by standardizing the narrow distributed polysaccharides using MALDI-MS method, reliable molecular weight information for dispersed polysaccharides could be obtained. The M (n),M (w) and PD of the water-insoluble Curdlan were found to be 22,000, 31,500 Da and 1.40, respectively.

An intelligent tutoring system for trauma management (Trauma-Teach): a preliminary report

Trauma-Teach is an interactive software for tutoring surgical trainees on medical trauma management procedures. Users of the system interact with a virtual patient suffering from trauma injuries. The task of the user is to stabilise the virtual patient, discover the underlying injuries and decide on an appropriate management plan. Artificial intelligence techniques are used to simulate the patient's pulmonary and cardiovascular systems in real time, determine the responses and results of treatments and diagnostics accordingly, model the patient deterioration if wrong actions are taken, and give a measure of reality to the system by selecting actual trauma cases from the hospital's database.

Analysis of a bioactive beta-(1 --> 3) polysaccharide (Curdlan) using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry

This paper focuses on the development of MALDI sample preparation protocols for the analysis of a bioactive beta-(1 --> 3) polysaccharide, i.e. Curdlan. The crude Curdlan sample was first separated into a low molecular weight water-soluble portion and a high molecular weight water-insoluble portion. The water-soluble portion was analyzed using a standard MALDI sample preparation method developed for dextran analysis. Two low-mass (<4000 Da) polysaccharide distributions differing by 16 Da were observed. For the analysis of the water-insoluble portion, several sample preparation protocols were evaluated using GPC-fractionated samples. A sample preparation method based on the deposition of the analyte solution with a mixture of 2,5-dihydroxybenzoic acid (DHB) and 3-aminoquinoline (3AQ) matrices in dimethyl sulfoxide (DMSO) at elevated temperature of 70 degrees C was found to reliably produce good MALDI spectra. MALDI analysis of the water-insoluble Curdlan portion gave number-average (Mn) and weight-average (Mw) molecular weights and polydispersity of 8000 Da, 8700 Da, and 1.10, respectively.

The application of computerised analysis of glow curves to personal dosimetry in LiF:Mg,Cu,P

In personnel monitoring services, it is important to omit the high-temperature annealing process so that large numbers of TL detectors can be produced economically. There are two efficient ways of reducing the residual signal of LiF:Mg,Cu,P. One is by increasing the maximum readout temperature and the other is by improving the preparation procedure (increasing the Cu concentration and the sintering temperature) but both reduce the TL sensitivity. In personal dosimetry the real dosimetric signals are separated from the residual signals by computerised analysis of glow curves. The adverse influence of the high residual signals of LiF:Mg.Cu.P TL material has been effectively eliminated and the sensitivity remains stable. A good dosimetric result using only reader measurement without pre-irradiation oven annealing is attained in a dose range of 50-80,000 microGy.

Influence of background exposure on detection and determination limits for a TL dosimetry system based on LiF:Mg,Cu,P(GR-200A)

Thermoluminescence dosemeters are widely used to monitor personal doses. For these low dose range applications, it is important to determine the detection limit L(D) and the determination limit L(Q) of the dosimetric system. The influence of background exposure on these limits for LiF:Mg,Cu,P(GR-200A) based TL dosimetry was investigated. Both the conventional analysis and the glow curve analysis methods were used to determinate these limits. The detection limit L(D) was compared with the recording level and the investigation level. A systematic error can occur in the occupational dose evaluation when the detection limit L(D) is more than the recording level. It was found that the L(D) of the dosimetric system-based LiF:Mg,Cu,P(GR-200A) was less than the recording level for exposure time tau > or = 10 days considering an annual dose limit of 1 mSv for the public recommended in ICRP Publication 60.

Mechanism underlying histamine-induced intracellular Ca2+ movement in PC3 human prostate cancer cells

The effect of histamine on intracellular free Ca2+ levels ([Ca2+]i) in PC3 human prostate cancer cells and the underlying mechanism were evaluated using fura-2 as a Ca2+ dye. Histamine at concentrations between 0.1 and 50 microM increased [Ca2+]i in a concentration-dependent manner with an EC50 value of 1 microM. The [Ca2+]i response comprised an initial rise and a slow decay, which returned to baseline within 3 min. Extracellular Ca2+ removal inhibited 50% of the [Ca2+]i signal. In the absence of extracellular Ca2+, after cells were treated with 1 microM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor), 10 microM histamine did not increase [Ca2+]i. After pretreatment with 10 microM histamine in a Ca2+-free medium for several minutes, addition of 3 mM Ca2+ induced [Ca2+]i increases. Histamine (10 microM)-induced intracellular Ca2+ release was abolished by inhibiting phospholipase C with 2 microM 1-(6-((17 beta-3- methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione (U73122), and by 10 microM pyrilamine but was not altered by 50 microM cimetidine. Collectively, the present study shows that histamine induced [Ca2+]i transients in PC3 human prostate cancer cells by stimulating H1 histamine receptors leading to Ca2+ release from the endoplasmic reticulum in an inositol 1,4,5-trisphosphate-dependent manner, and by inducing Ca2+ entry.

Effect of oleamide on Ca(2+) signaling in human bladder cancer cells

The effect of oleamide, a sleep-inducing endogenous lipid in animal models, on intracellular free levels of Ca(2+) ([Ca(2+)](i)) in non-excitable and excitable cells was examined by using fura-2 as a fluorescent dye. [Ca(2+)](i) in pheochromocytoma cells, renal tubular cells, osteoblast-like cells, and bladder cancer cells were increased on stimulation of 50 microM oleamide. The response in human bladder cancer cells (T24) was the greatest and was further explored. Oleamide (10-100 microM) increased [Ca(2+)](i) in a concentration-dependent fashion with an EC(50) of 50 microM. The [Ca(2+)](i) signal comprised an initial rise and a sustained plateau and was reduced by removing extracellular Ca(2+) by 85 +/- 5%. After pre-treatment with 10-100 microM oleamide in Ca(2+)-free medium, addition of 3 mM Ca(2+) increased [Ca(2+)](i) in a manner dependent on the concentration of oleamide. The [Ca(2+)](i) increase induced by 50 microM oleamide was reduced by 100 microM La(3+) by 40%, but was not altered by 10 microM nifedipine, 10 microM verapamil, and 50 microM Ni(2+). In Ca(2+)-free medium, pre-treatment with thapsigargin (1 microM), an endoplasmic reticulum Ca(2+) pump inhibitor, abolished 50 microM oleamide-induced [Ca(2+)](i) increases; conversely, pretreatment with 50 microM oleamide reduced 1 microM thapsigargin-induced [Ca(2+)](i) increases by 50 +/- 3%. Suppression of the activity of phospholipase C with 2 microM U73122 failed to alter 50 microM oleamide-induced Ca(2+) release. Linoleamide (10-100 microM), another sleep-inducing lipid with a structure similar to that of oleamide, also induced an increase in [Ca(2+)](i). Together, it was shown that oleamide induced significant [Ca(2+)](i) increases in cells by a phospholipase C-independent release of Ca(2+) from thapsigargin-sensitive stores and by inducing Ca(2+) entry.

Fendiline mobilizes intracellular Ca2+ in Chang liver cells

1. The effects of the antianginal drug fendiline (N-[3,3-diphenylpropyl]-alpha-methyl-benzylamine) on intracellular free Ca2+ levels ([Ca2+](i)) in Chang liver cells were evaluated using fura-2 as a fluorescent Ca2+ indicator. 2. Fendiline (1-100 micromol/L) increased [Ca2+](i) in a concentration-dependent manner, with an EC50 of 25 micromol/L. 3. The [Ca2+](i) response was composed of an initial rise and a slow decay to a sustained phase. Removal of extracellular Ca2+ partly reduced the [Ca2+](i) signals. 4. Fendiline (10 micromol/L)-induced release of intracellular Ca2+ was reduced by 65% following pretreatment with 1 micromol/L thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor) to deplete Ca2+ stored in the endoplasmic reticulum. 5. After pretreatment with 10 micromol/L fendiline in Ca2+-free medium for several minutes, addition of 3 mmol/L Ca2+ induced an increase in [Ca2+](i) of a magnitude four-fold greater than control. This increase in [Ca2+](i) was not reduced by 10 micromol/L SKF96365, econazole, nifedipine or verapamil. 6. Fendiline (10 micromol/L)-induced release of intracellular Ca2+ was not altered by inhibition of phospholipase C with 2 micromol/L 1-(6-((17beta-3-methoxyestra-1,3,5(10)-trien-17-yl)amino) hexyl)-1H-pyrrole-2,5-dione (U73122). 7. The results of the present study show that fendiline induces an increase in [Ca2+](i) in Chang liver cells by releasing stored Ca2+ in an inositol 1,4,5-trisphosphate-independent manner and by causing extracellular Ca2+ influx.

Fendiline, an anti-anginal drug, increases intracellular Ca2+ in PC3 human prostate cancer cells

BACKGROUND

The effects of the anti-anginal drug fendiline on intracellular Ca2+ concentrations ([Ca2+]i) in human PC3 prostate cancer cells were examined.

METHODS

[Ca2+]i was measured using the fluorescent dye fura-2.

RESULTS

Fendiline (0.5-100 microM) increased [Ca2+]i in a concentration-dependent manner. Ca2+ removal partly inhibited the Ca2+ signals. In Ca2+-free medium, pretreatment with 100 microM fendiline inhibited most of the [Ca2+]i increase induced by 1 microM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor), and pretreatment with thapsigargin abolished the fendiline-induced [Ca2+]i increases. Adding 3 mM Ca2+ increased [Ca2+]i in cells pretreated with 0.5-200 microM fendiline in Ca2+-free medium. Pretreatment with 1 microM U73122 to block the formation of inositol-1.4.5-trisphosphate (IP3) did not alter fendiline-induced internal Ca2+ release.

CONCLUSIONS

The anti-anginal drug fendiline induced internal Ca2+ release and external Ca2+ entry. Because prolonged increases in [Ca2+]i may lead to cell injury and death, the long-term effect of fendiline on the function of prostate cancer cells should be investigated.

Effect of the neuroprotective agent riluzole on intracellular Ca2+ levels in IMR32 neuroblastoma cells

Riluzole is an effective neuroprotective drug. Its effect on intracellular free Ca2+ levels ([Ca2+]i) has not been explored. This study examined the effect of riluzole on [Ca2+]i in IMR32 neuroblastoma cells using fura-2 as a Ca2+ probe. Riluzole 0.1-1 mM increased [Ca2+]i in a concentration-dependent manner. Removal of extracellular Ca2+ inhibited the response by 52 +/- 5%. The [Ca2+]i increase induced by 0.2 mM riluzole was unaltered by 0.1 mM La3+ or 10 microM verapamil, but was inhibited by 51 +/- 4% by 10 microM nifedipine. In Ca2+-free medium, pretreatment with 1 microM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor) reduced the 0.2 mM riluzole-induced Ca2+ release by 44 +/- 3%; this reduction was augmented to 66 +/- 5% by additionally depleting the Ca2+ stores in the Golgi complex with 50 microM brefeldin A. Inhibition of inositol 1,4,5-trisphosphate formation by 2 microM U73122, a phospholipase C inhibitor, did not affect Ca2+ release induced by 0.2 microM riluzole. It was concluded that the neuroprotective agent riluzole increased [Ca2+]i in IMR32 neuroblastoma cells concentration-dependently by releasing Ca2+ from multiple stores in an inositol 1,4,5-trisphosphate-independent manner and also by inducing nifedipine-sensitive Ca2+ influx.

Effect of diethylstilbestrol (DES) on intracellular Ca(2+) levels in renal tubular cells

The effect of the estrogen diethylstilbestrol (DES) on intracellular Ca(2+) concentrations ([Ca(2+)](i)) in Madin Darby canine kidney (MDCK) cells was investigated, using the fluorescent dye fura-2 as a Ca(2+) indicator. DES (10-50 microM) evoked [Ca(2+)](i) increases in a concentration-dependent manner. Extracellular Ca(2+) removal inhibited 45 +/- 5% of the Ca(2+) response. In Ca(2+)-free medium, pretreatment with 50 microM DES abolished the [Ca(2+)](i) increases induced by 2 microM carbonylcyanide m-chlorophenylhydrazone (CCCP; a mitochondrial uncoupler) and 1 microM thapsigargin (an endoplasmic reticulum Ca(2+) pump inhibitor); and pretreatment with CCCP and thapsigargin partly inhibited DES-induced [Ca(2+)](i) signals. Adding 3 mM Ca(2+) increased [Ca(2+)](i) in cells pretreated with 50 microM DES in Ca(2+)-free medium, suggesting that DES may induce capacitative Ca(2+) entry. 17beta-Estradiol (2-20 microM) increased [Ca(2+)](i), but 100 microM diethylstilbestrol dipropionate had no effect. Pretreatment with the phospholipase C inhibitor U73122 (1 microM) to abolish inositol 1,4,5-trisphosphate formation inhibited 30% of DES-induced Ca(2+) release. DES (20 microM) also increased [Ca(2+)](i) in human normal hepatocytes and osteosarcoma cells. Cumulatively, this study shows that DES induced rapid and sustained [Ca(2+)](i) increases by releasing intracellular Ca(2+) and triggering extracellular Ca(2+) entry in renal tubular cells.

Tamoxifen-induced Ca2+ mobilization in bladder female transitional carcinoma cells

This study examined the effect of tamoxifen, an anti-breast cancer drug, on Ca2+ handling in bladder female transitional cancer cells. Changes in cytosolic free Ca2+ levels were recorded by using the Ca2+-sensitive dye fura-2. In a dose-dependent manner, tamoxifen induced intracellular free Ca2+ concentrations ([Ca2+]i) increases between 5 and 20 microM with an EC50 of 10 microM. External Ca2+ removal reduced the response by 60+/-6%. Addition of 3 mM Ca2+ caused a [Ca2+]i increase after pretreatment with 10 microM tamoxifen in Ca2+-free medium. In Ca2+-free medium, pretreatment with 10 microM tamoxifen abolished the [Ca2+]i increase induced by 1 microM thapsigargin, an endoplasmic reticulum Ca2+ pump inhibitor. Conversely, pretreatment with 1 microM thapsigargin prevented tamoxifen from releasing more Ca2+. Inhibition of phospholipase C-dependent inositol 1,4,5-tris-phosphate formation with 2 microM U73122 did not alter 10 microM tamoxifen-induced Ca2+ release. The [Ca2+]i increase induced by 5 microM tamoxifen was not altered by 10 microM La3+, nifedipine, verapamil, and diltiazem. Collectively, it was found that tamoxifen increased [Ca2+]i in bladder cancer cells by releasing Ca2+ from the endoplasmic reticulum Ca2+ stores in a manner independent of phospholipase C activity, and by inducing Ca2+ entry from external medium.

Effect of fluoxetine on intracellular Ca2+ levels in bladder female transitional carcinoma (BFTC) cells

The effect of the antidepressant fluoxetine on Ca2+ signaling in cultured cells was largely unknown. The effect of various concentrations of fluoxetine on [Ca 2+] i in populations of bladder female transitional cancer (BFTC) cells was evaluated by using fura-2 as a Ca2+ probe. Fluoxetine increased [Ca 2+] i concentration dependently (20-100 microM) with an EC50 value of 30 microM. The response was inhibited by 50-60% on extracellular Ca2+ removal. In Ca2+ -free medium, pretreatment with 1 microM thapsigargin (an inhibitor of the endoplasmic reticulum Ca2+ pump) abolished 50 microM fluoxetine-induced Ca2+ release; whereas pretreatment with fluoxetine did not alter the thapsigargin-induced Ca2+ response. Addition of 3 mM Ca2+ increased [Ca 2+] i after pretreatment with 50 microM fluoxetine in Ca2+ -free medium, suggestive of fluoxetine-induced capacitative Ca2+ entry. Suppression of inositol 1,4,5-trisphosphate formation by 2 microM U73122 (a phospholipase C inhibitor) did not affect 50 microM fluoxetine-induced Ca2+ release. Collectively, this study shows that fluoxetine increased [Ca 2+] i in bladder cancer cells in a concentration-dependent fashion, by releasing Ca2+ from thapsigargin-sensitive Ca2+ stores in an IP3-independent manner, and by inducing Ca2+ influx from extracellular medium.

Fendiline-Induced Ca2+ movement in A10 smooth muscle cells

The effect of fendiline, an anti-anginal drug, on cytosolic free Ca2+ levels ([Ca2+]i) in A10 smooth muscle cells was explored by using fura-2 as a Ca2+ indicator. Fendiline at concentrations between 10-50 microM increased [Ca2+]i in a concentration-dependent manner with an EC50 of 20 microM. External Ca2+ removal reduced the Ca2+ signal by 75%. Addition of 3 mM Ca2+ increased [Ca2+]i in cells pretreated with fendiline in Ca2+-free medium. The 50 microM fendiline-induced [Ca2+]i increase in Ca2+-containing medium was inhibited by 10 microM of La3+, nifedipine, or verapamil. In Ca2+-free medium, pretreatment with 1 microM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor) to deplete the endoplasmic reticulum Ca2+ store partly inhibited 50 microM fendiline-induced Ca2+ release; whereas pretreatment with 50 microM fendiline abolished 1 microM thapsigargin-induced Ca2+ release. Inhibition of phospholipase C activity with 2 microM U73122 did not alter 50 microM fendiline-induced Ca2+ release. Incubation with 50 microM fendiline for 10-30 min decreased cell viability by 10-20%. Together, the findings indicate that in smooth muscle cells fendiline induced [Ca2+]i increases. Fendiline acted by activating Ca2+ influx via L-type Ca2+ channels, and by releasing internal Ca2+ in a phospholipase C-independent manner. Prolonged exposure of cells to fendiline induced cell death.

Characterization of histamine-induced increases in intracellular free Ca2+ concentrations in Chang liver cells

The effect of histamine on intracellular free Ca2+ levels ([Ca2+]i) in Chang liver cells were investigated by using fura-2 as a Ca2+ dye. Histamine (0.2-50 microM) increased [Ca2+]i in a concentration-dependent manner with an EC50 value of 0.8 microM. The [Ca2+]i response comprised an initial rise, a slow decay, and a sustained phase. Extracellular Ca2+ removal inhibited 50% of the maximum [Ca2+]i signal and abolished the sustained phase. After pretreatment with 5 microM histamine in Ca2+-free medium for 4 min, addition of 3 mM Ca2+ induced a [Ca2+]i increase with a magnitude 7-fold greater than control. In Ca2+-free medium, after treatment with 1 microM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor), 5 microM histamine failed to increase [Ca2+]i. Histamine (5 microM)-induced intracellular Ca2+ release was abolished

Fluoxetine-induced Ca2+ signals in Madin-Darby canine kidney cells

The effect of fluoxetine on Ca2+ signaling in Madin-Darby canine kidney (MDCK) cells was investigated by using fura-2 as a Ca2+ probe. Fluoxetine increased [Ca2+]i concentration-dependently between 5 microM and 200 microM with an EC50 value of 40 microM. The response was reduced by external Ca2+ removal by 30%40%. In Ca2+-free medium pretreatment with 1 microM thapsigargin, an inhibitor of the endoplasmic reticulum Ca2+ pump, abolished 100 microM fluoxetine-induced Ca2+ release. Addition of 3 mM Ca2+ to Ca2+-free medium increased [Ca2+]i when cells were pretreated with 100 microM fluoxetine. Suppression of 1,4,5-trisphosphate (IP3) formation by 2 microM U73122 (a phospholipase C inhibitor) did not affect 100 microM fluoxetine-induced Ca2+ release. Fluoxetine (5-100 microM) also increased [Ca2+]i in neutrophils, prostate cancer cells and bladder cancer cells from human and rat glioma cells.

Novel effects of 5,8,11-eicosatriynoic acid, a lipoxygenase inhibitor, on Ca2+ mobilization in Madin Darby canine kidney cells

The effect of 5,8,11-eicosatriynoic acid, a widely used lipoxygenase inhibitor, on Ca2+ fate in Madin Darby canine kidney cells was examined by using fura-2 as a Ca2+ probe. At concentrations between 2-100 microM 5,8,11-eicosatriynoic acid increased [Ca2+]i concentration-dependently with an EC50 of 20 microM . Extracellular Ca2+ removal decreased the Ca2+ signals, indicating that 5,8,11-eicosatriynoic acid triggered Ca2+ release and Ca2+ influx. 5,8,11 -Eicosatriynoic acid (30 microM) induced a [Ca2+]i increase in Ca2+-free medium after pretreatment with carbonylcyanide m-chlorophenylhydrazone (2 microM), a mitochondrial uncoupler, and thapsigargin (1 microM), an endoplasmic reticulum Ca2+ pump inhibitor for 20 min. Conversely, 5,8,11-eicosatriynoic acid pretreatment almost abolished the Ca2+ release induced by carbonylcyanide m-chlorophenylhydrazone and thapsigargin. These results suggest that 30 microM 5,8,11-eicosatriynoic acid released Ca2+ from the endoplasmic reticulum, mitochondria and other stores. Addition of 3 mM Ca2+ increased [Ca2+]i after preincubation with 2-50 microM 5,8,11-eicosatriynoic acid for 10 min. in Ca2+-free medium concentration-dependently. Pretreatment with 10 microM La3+ abolished 30 microM 5,8,11-eicosatriynoic acid -induced [Ca2+]i increases, but adding La3+ during the decay phase had no effect. 5,8,11-Eicosatriynoic acid-induced Ca2+ release was not altered by inhibiting phospholipase C with 2 microM 1-(6-((17beta-3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione (U73122), but was decreased by 60% by 40 microM aristolochic acid. Several other lipoxygenase inhibitors such as baicalein (50 microM), 5.8.11.14-eicosatetraynoic acid (ETYA; 0.1-0.2 mM), caffeic acid (5-50 microM), esculetin (5-50 microM), alpha-pentyl-3-(2-quinolinylmethoxy)-benzenemethanol (REV-5901; 0.1-0.2 mM) and alpha-pentyl-4-(2-quinolinylmethoxy)-benzenemethanol (L-655238; 80-100 microM) had no effect on [Ca2+]i. Collectively, the data suggest that the lipoxygenase inhibitor 5,8,11-eicosatriynoic acid induced a [Ca2+]i increase in renal tubular cells concentration-dependently, by releasing intracellular Ca2+ from multiple stores in an inositol 1,4,5-trisphosphate-independent manner, and by inducing extracellular Ca2+ influx in a La3+-sensitive manner.

Histamine-Induced increases in intracellular free Ca2+ levels in hepatoma cells

The effect of histamine on intracellular free Ca2+ levels ([Ca2+]i) in HA22/VGH human hepatoma cells were evaluated using fura-2 as a fluorescent Ca2+ dye. Histamine (0.2-5 microM) increased [Ca2+]i in a concentration-dependent manner with an EC50 value of about 1 microM. The [Ca2+]i response comprised an initial rise, a slow decay, and a sustained phase. Extracellular Ca2+ removal inhibited 50% of the [Ca2+]i signal. In Ca2+-free medium, after cells were treated with 1 microM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor), 5 microM histamine failed to increase [Ca2+]i. After pretreatment with 5 microM histamine in Ca2+-free medium for 4 min, addition of 3 mM Ca2+ induced a [Ca2+]i increase of a magnitude 7-fold greater than control. Histamine (5 microM)-induced intracellular Ca2+ release was abolished by inhibiting phospholipase C with 2 microM 1-(6-((17beta-3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione (U73122), and by 5 microM pyrilamine but was not altered by 50 microM cimetidine. Together, this study shows that histamine induced [Ca2+]i increases in human hepatoma cells by stimulating H1, but not H2, histamine receptors. The [Ca2+]i signal was caused by Ca2+ release from thapsigargin-sensitive endoplasmic reticulum in an inositol 1,4,5-trisphosphate-dependent manner, accompanied by Ca2+ entry.

Effect of betulinic acid on intracellular-free Ca(2+) levels in Madin Darby canine kidney cells

The effect of betulinic acid, an anti-tumor and apoptosis-inducing natural product, on intracellular-free levels of Ca(2+) ([Ca(2+)](i)) in Madin Darby canine kidney (MDCK) cells was examined by using fura-2 as a Ca(2+) dye. Betulinic acid caused significant increases in [Ca(2+)](i) concentration dependently between 25 and 500 nM with an EC(50) of 100 nM. The [Ca(2+)](i) signal was composed of an initial gradual rise and a plateau. The response was decreased by removal of extracellular Ca(2+) by 45+/-10%. In Ca(2+)-free medium, pretreatment with 1 microM thapsigargin (an endoplasmic reticulum Ca(2+) pump inhibitor) abolished 250 microM betulinic acid-induced [Ca(2+)](i) increases. Conversely, pretreatment with betulinic acid only partly inhibited thapsigargin-induced [Ca(2+)](i) increases. Addition of 3 mM Ca(2+) induced a [Ca(2+)](i) increase after pretreatment with 250 nM betulinic acid in Ca(2+)-free medium for 5 min. This [Ca(2+)](i) increase was not altered by the addition of 20 microM SKF96365 and 10 microM econazole. Inhibiting inositol 1,4,5-trisphosphate formation with the phospholipase C inhibitor U73122 (2 microM) abolished 250 nM betulinic acid-induced Ca(2+) release. Pretreatment with 10 microM La(3+) inhibited 250 nM betulinic acid-induced [Ca(2+)](i) increases by 85+/-3%; whereas 10 microM of verapamil, nifedipine and diltiazem had no effect. In Ca(2+) medium, pretreatment with 2.5 nM betulinic aid for 260 s potentiated 10 microM ATP and 1 microM thapsigargin-induced [Ca(2+)](i) increases by 33+/-3% and 45+/-3%, respectively. Trypan blue exclusion revealed that acute exposure of 250 nM betulinic acid for 2-30 min decreased cell viability by 6+/-2%, which could be prevented by pretreatment with 2 microM U731222. Together, the results suggest that betulinic acid induced significant [Ca(2+)](i) increases in MDCK cells in a concentration-dependent manner, and also induced mild cell death. The [Ca(2+)](i) signal was contributed by an inositol 1,4, 5-trisphosphate-dependent release of intracellular Ca(2+) from thapsigargin-sensitive stores, and by inducing Ca(2+) entry from extracellular medium in a La(3+)-sensitive manner.

NPC-14686, a novel anti-inflammatory agent, increased intracellular Ca(2+) concentrations in MDCK renal tubular cells

The effect of NPC-14686 (Fmoc-L-homophenylalanine), a novel anti-inflammatory agent on intracellular free Ca(2+) concentrations ([Ca(2+)](i)) in Madin Darby canine kidney (MDCK) renal tubular cells, was investigated, using fura-2 as a Ca(2+) dye. At concentrations between 10 and 200 microM NPC-14686 increased [Ca(2+)](i) concentration dependently. The [Ca(2+)](i) signal comprised an initial rise and a sustained phase. Ca(2+) removal inhibited the Ca(2+) signals by 90%. In Ca(2+)-free medium, pretreatment with 100 microM NPC-14686 nearly abolished the [Ca(2+)](i) increase induced by 1 microM thapsigargin (an endoplasmic reticulum Ca(2+) pump inhibitor) and abolished the [Ca(2+)](i) increase induced by 2 microM carbonylcyanide m-chlorophenylhydrazone (CCCP) (a mitochondrial uncoupler). NPC-14686 (100 microM) induced a slight [Ca(2+)](i) increase after pretreatment with 2 microM CCCP and 1 microM thapsigargin. Addition of 3 mM Ca(2+) elicited a [Ca(2+)](i) increase in cells pretreated with 100 microM NPC-14686 in Ca(2+)-free medium. Inhibition of inositol-1,4,5-trisphosphate (IP(3)) production by suppressing phospholipase C with 2 microM U73122 did not alter NPC-14686-induced Ca(2+) release. Trypan blue exclusion revealed that incubation with 10 or 200 microM NPC-14686 for 1-30 min decreased cell viability by 10-20% concentration dependently. Collectively, the results demonstrate that, in MDCK tubular cells, NPC-14686 induced Ca(2+) release followed by Ca(2+) entry, with the latter playing a major role. NPC-14686 appears to release intracellular Ca(2+) in an IP(3)-uncoupled manner. NPC-14686 may be of mild cytotoxicity.

Dual effect of tamoxifen, an anti-breast-cancer drug, on intracellular Ca(2+) and cytotoxicity in intact cells

The effect of tamoxifen on Ca(2+) signaling and viability in Madin Darby canine kidney (MDCK) cells was investigated by using fura-2 as a Ca(2+) probe. Tamoxifen evoked a rise in cytosolic free Ca(2+) levels ([Ca(2+)](i)) concentration-dependently between 1 and 50 microM with an EC50 of 10 microM. The response was decreased by extracellular Ca(2+) removal. In Ca(2+)-free medium, pretreatment with 5 microM tamoxifen abolished the [Ca(2+)](i) increase induced by the endoplasmic reticulum Ca(2+) pump inhibitor thapsigargin (1 microM), but pretreatment with brefeldin A (50 microM; a Ca(2+) mobilizer of the Golgi complex), thapsigargin (an inhibitor of the endoplasmic reticulum Ca(2+) pump), and carbonylcyanide m-chlorophenylhydrazone (CCCP; a mitochondrial uncoupler), only partly inhibited tamoxifen-induced [Ca(2+)](i) increases. This suggests that tamoxifen released Ca(2+) from multiple pools. Addition of 3 mM Ca(2+) induced a [Ca(2+)](i) rise after pretreatment with 5 microM tamoxifen in Ca(2+)-free medium. Inhibiting inositol 1,4,5-trisphosphate formation with the phospholipase C inhibitor U73122 (2 microM) did not alter 5 microM tamoxifen-induced Ca(2+) release. The [Ca(2+)](i) increase induced by 5 microM tamoxifen was not altered by La(3+), nifedipine, verapamil, or diltiazem. Tamoxifen (1-10 microM) decreased cell viability in a concentration- and time-dependent manner. Tamoxifen (5 microM) also increased [Ca(2+)](i) in neutrophils, bladder cancer cells, and prostate cancer cells from humans and glioma cells from rats. Collectively, it was found that tamoxifen increased [Ca(2+)](i) in MDCK cells by releasing Ca(2+) from multiple Ca(2+) stores in a manner independent of the production of inositol 1,4, 5-trisphosphate and also by triggering Ca(2+) influx from extracellular space. The [Ca(2+)](i) increase was accompanied by cytotoxicity.

Cost analyses of home care and nursing home services in the southern Taiwan area

This study compares the cost of long-term care provided at patient homes with that of long-term care provided in nursing homes in southern Taiwan. Caring for a patient with a high degree of dependence at home is more expensive than caring for a patient in a nursing home facility when family costs and provider costs are considered together. This phenomenon is not demonstrated for patients with medium degrees of dependence. To be cost-effective, home care services should target patients with medium physical disability, and nursing home care should focus on patients with high levels of dependence.

Willingness of families caring for victims of dementia to pay for nursing home care: results of a pilot study in Taiwan

In order to examine the value family caregivers attach to the benefits associated with nursing home services, this contingent survey was designed to investigate the willingness of family caregivers of dementia victims to pay for nursing home care. A total of 136 members of families of dementia patients from the department of neurology and psychiatry of four medical centers in Taiwan were interviewed by phone. These family members provided in-home care for dementia victims and had expressed the need for nursing home placement. These family caregivers were asked to explicitly state the maximum amount of family income per month they are able to give up to receive nursing home services. The willingness to pay (WTP) for nursing home care ranged from US$185 to $2,407 per month, and 37.5 percent of the family caregivers interviewed indicated a willingness to pay at least 50 percent of the monthly family income for nursing home placement. The amount of monthly family income was strongly associated with the WTP for nursing home care in dollars. Age and education of the caregiver, and accessibility of nursing home care were significantly associated with WTP in both cost range and percentage of monthly family income. Interviewees who were older than 65 years (odds ratio is 3.52), and educated equal to or above senior high school (odds ratio is 5.57) were inclined to pay at least 50 percent of monthly family income for nursing home placement. As other variables were adjusted, respondents older than 65 years were willing to pay US$208.4 per month more than those younger than 65 years for nursing home placement; and the educated equal to or above senior high school were inclined to pay US$171.9 per month more than those with less than a senior high school education. The easier it was to find nursing home agencies near the residence, the more willing the family was to pay at least 50 percent of their monthly family income for nursing home services; with an odds ratio of 16.51. The families with the higher accessibility to nursing home agencies were willing to pay US$174.3 per month more than caregivers with lower accessibility. Family caregivers, who were older than 65 years, educated above the senior high school level, with a higher family income, and easier accessibility to nursing home services, were likely to attach higher economic values to nursing home placement.

Cost comparisons between family-based care and nursing home care for dementia

A prospective study was carried out in Taiwan to measure the family cost of caregiving at home for 289 patients newly diagnosed with dementia (106 with senile-type dementia, 171 with vascular-type dementia). Their families were first interviewed in the outpatient department and then followed for 1 month after the dementia diagnosis was made. Simultaneously, the costs for providing nursing home care to patients with dementia were calculated using accounting data reported from six nursing homes. Comparisons were made between the amount and type of cost encountered by families and by nursing homes to determine whether family-based care was cheaper and more appropriate than nursing home care for dementia patients with different functional levels. The results showed that higher costs were encountered for caregiving at home when the patients had severe dependence. This tendency was more evident for patients with senile dementia than for patients with vascular-type dementia. The cost of labour was an important expense for families caring for patients at home (at least 85% of family costs). Our findings suggest that, when family labour cost is considered, nursing home care is less expensive than family-based care for long-term care, especially for dementia patients with severe or moderate dependence. Nursing home care is also a better choice when patients have great need for multiple health services.

The willingness of families caring for victims of stroke to pay for in-home respite care--results of a pilot study in Taiwan

This contingent survey was designed to investigate the willingness of family caregivers of stroke victims to pay for in-home respite care. Between September 1996 and December 1996, a designated family member from each family of 174 vascular accident patients hospitalized in the Taipei Metropolitan Area, including two medical centers, received the first interview during preparation and planning for discharge of the patient from the hospital, and follow up interview in their own homes at the end of the second month after the patient was discharged from the hospital. A willingness to pay for in-home respite care was measured as the percentage of monthly family income which would be sacrificed to receive the respite care. Logistic regressions were used to perform multivariate analysis. The willingness to pay for respite care ranged from US$ 363 to 2182, and 42.5% of the family caregivers interviewed indicated a willingness to pay at least 50% of monthly family income for respite care. Family income was strongly associated with the amount of money that family caregivers were willing to pay for respite care. After results were adjusted for the effect of variance in income level, the degree of dependence of patients on the caregiver was significantly associated with the percentage of monthly family income for respite care. The more severe the physical dysfunction of patient, the higher the willingness to pay for in-home respite care utilization. Initially, respite care could be provided to families caring for patients with severe dysfunction, and then the scope enlarged to include caregivers taking care of patients with mild dysfunction.

Consistency between preference and use of long-term care among caregivers of stroke survivors

Effective arguments have been made for the importance of expanded attention to understanding how family preferences influence decisions to choose long-term care. The effects of preference on the utilization of long-term care deserve further research, especially on a longitudinal basis. The family members of 582 first-time stroke patients from the neurology departments of four teaching hospitals in Taiwan were categorized into two groups based on their attitudes toward type of long-term care, i.e., a preference for nursing home care (n1 = 324) or a preference for home care (n2 = 258). The consistency rate between preference and utilization of the type of long-term care was estimated by the division of number of families preferring one type of long-term care by the number of families actually utilizing the services preferred. Results indicated that the consistency rate for those with nursing home preference was 8.3% while the consistency rate for those with home care preference was 94.2%. Accessibility of nursing home facilities near family residences was significantly associated with whether those preferring nursing home services actually utilized them, and the odds ratio was 20.8. The family manpower available for caregiving at home was tremendously associated with whether families utilized home care when home care was preferred; the odds ratio was 33.3. The preference for the type of long-term care was a strong predictor of the utilization when home care was preferred, yet not when a nursing home was preferred. The low consistency between preference and utilization for nursing homes preferred is due to the low accessibility of nursing home facilities in Taiwan. How to provide sufficient support to families for caregiving at home, and how to deal with the barrier of accessibility to nursing home services should be two major concerns for those who are planning and operating the long-term care system and for those trying to design institutional services and noninstitutional services as alternatives.

Hepatitis B, 1997 and the Chinese community--an appraisal of their relationships

In 1997, Hong Kong's sovereignty will go back to China. The United Kingdom has granted 50,000 families the right of abode to settle here. It is estimated that these 50,000 families will consist of approximately 225,000 people in all. Hepatitis B virus infection is extremely common in Hong Kong-50 per cent of the local population have been infected by the virus. Should the Department of Health consider implementing and introducing a screening and immunization programme? What is the current level of understanding about the virus among the Chinese community and health care professionals in the United Kingdom? Findings from a health promotion project have revealed that there is a gap in health care professionals' and patients' understanding of the issue. There is a need to raise awareness, to provide more information for health care professionals and patients, and to give serious consideration to a screening and vaccination programme.

Therapeutic lamellar keratectomy in the management of experimental keratomycosis

Keratomycosis, a vision-threatening corneal infection, is a challenge to the ophthalmologist because it is often refractory to medical treatment. Surgical keratectomy may not only debulk the major infectious source but potentiate the intracorneal penetration of the antifungal agents. To evaluate the efficacy of keratectomy in managing the fungal corneal ulcer, three common keratomycosis models, Candida, Fusarium, and Aspergillus keratitis, were established in 46 eyes of 23 rabbits (each group had 14, 16 and 16 eyes respectively). Within each keratitis group, the infected eyes were randomly divided into equally numbered experimental and control subgroups. The eyes of the experimental subgroups underwent therapeutic lamellar keratectomy once the typical fungal corneal infection had developed after inoculation. Following keratectomy, eyes of both the treated and control groups received natamycin eyedrops and were regularly examined biomicroscopically. Our results showed that therapeutic lamellar keratectomy is beneficial in chronic, indolent keratitis, such as Candida and Fusarium keratitis, where it promoted corneal healing and shortened the duration of treatment required. The procedure is a valuable adjunctive measure for antifungal agents in these two types of keratitis. However, acute keratitis of the Aspergillus group did not benefit from keratectomy; in these cases, surgery may actually increase the risk of corneal perforation.