Does social participation by the elderly reduce mortality and cognitive impairment?

PURPOSE

This longitudinal study examines the effect of social participation on mortality and cognitive impairment for the elderly in Taiwan.

METHODS

Data were from an elderly population panel in Taiwan 'The Survey of Health and Living Status of the Elderly' 1993-1999. Social participation was defined as paid/unpaid job and participating in volunteer and social groups. Logistic regression analysis was used for predicting the influence of social participation to 6-year mortality and cognitive function impairment, by controlling of socioeconomic status and health-related variables.

RESULTS

The elderly with continuous paid work were more likely to participate in social groups. Having paid or unpaid work at the baseline year could lower the risk of mortality six years later, especially for men. Having unpaid work was associated with a higher risk of impaired cognitive function compared to that of non-workers. Participating in a religious group reduced the risk of mortality for women and participating in political groups reduced the risk of impaired cognitive function for men.

DISCUSSION

Participating in some types of social activities may reduce mortality or cognitive function impairment in the elderly. However, different activities, gender roles and uneven opportunities for work and social group participation may affect the risk of these endpoints.

Familial aggregation of metabolic syndrome among the Chinese: report from the Chin-Shan community family study

Genetic study on metabolic syndrome is a great challenge, due to its complex traits and the pleiotropic manifestation of atherosclerosis. Familial aggregation and recurrence risk ratio can provide the insight of possible genetic mechanism. The Chin-Shan community family study was based on adolescent probands and their relatives (1356 subjects) who were recruited from one junior high school in the community. Structured questionnaires and biochemical measures were obtained in standard procedures. Definition of metabolic syndrome was followed using the criteria defined by the third adult treatment panel, with a modification of the criteria for adolescent and Asian population. Grandmothers had the highest frequencies (70%) in metabolic syndrome and various atherosclerotic risks. Three factors were found and thus explained 68% of the overall variance. Estimated heritability was the highest in LDL and cholesterol factor (0.36 and 0.40), then blood pressure/obesity factor (0.27), and insulin resistance/dyslipidemia (0.27). Recurrence risk ratio among siblings was 2.95 (95% confidence interval [CI]: 1.39-6.26). The adjusted odds ratio (OR) of proband's metabolic syndrome status was 1.99 (95% CI: 1.08-3.66). The adjusted odds ratios for the three factors for predicting metabolic syndrome were all significant, with highest risk in blood pressure/obesity factor (OR: 1.27, CI: 1.22-1.33), then insulin resistance/dyslipidemia (OR: 1.29, CI: 1.16-1.23). This study demonstrated clearly familial aggregation and recurrence risk ratio of metabolic syndrome and components among the general ethnic Chinese population in Taiwan.

Epitaxial Growth of InN Films by Molecular-Beam Epitaxy Using Hydrazoic Acid (HN3) as an Efficient Nitrogen Source

Epitaxial InN films have been successfully grown on c-plane GaN template by gas-source molecular-beam epitaxy with hydrazoic acid (HN3) as an efficient nitrogen source. Results in residual-gas analyzer show that the HN3 is highly dissociated to produce nitrogen radicals and can be controlled in the amounts of active nitrogen species by tuning HN3 pressure. A flat and high-purity InN epifilm has been realized at the temperature near 550 degrees C, and a growth rate of 200 nm/hr is also achieved. Moreover, the epitaxial relationship of the InN(002) on the GaN(002) is reflected in the X-ray diffraction, and the full-width at half-maximum of the InN(002) peak as narrow as 0.05 degrees is related to a high-quality crystallinity. An infrared photoluminescence (PL) emission peak at 0.705 eV and the integrated intensity increasing linearly with excitation power suggest that the observed PL can be attributed to a free-to-bound recombination.

Interleukin-1 alpha polymorphism has influence on late-onset sporadic Parkinson's disease in Taiwan

Inflammatory events may contribute to the pathogenesis of Parkinson's disease (PD) and interleukin 1 (IL-1) may exert both neurotoxic and neuroprotective effects. We conducted a case-control study in a cohort of 493 PD cases and 388 ethnically matched controls to investigate the association of IL-1alpha C-889T and IL-1beta C-511T polymorphisms with the risk of PD. No significant difference in the genotype distribution of the analyzed polymorphisms was found between PD and controls. However, after stratification by age, individuals over 70 years of age carrying IL-1alpha-889 C/T genotype demonstrated a significant decrease in risk of developing PD (OR = 0.44; 95% CI = 0.22-0.88, p = 0.021) and the decrease is strengthened by IL-1beta-511 T-carrying genotype (OR = 0.28; 95% CI = 0.11-0.71, p = 0.008). Our data suggest that IL-1alpha, acting synergistically with IL-1beta, plays role in PD susceptibility among Taiwanese people older than 70 years of age.

Evaluation of different bonded investments for dental titanium casting

The properties of several different investments were investigated including phosphate bonded, magnesia bonded, and alumina cement investments. Measurements included the setting expansion, thermal expansion, and compressive strength of investments, as well as the tensile strength, elongation, Vickers hardness (VHN) and surface roughness of titanium castings. For phosphate bonded investment, the setting expansion after being mixed with its own mixing solution was 2.10%, which was larger than the other investments; the thermal expansion was -0.25% at 200 degrees C, the compressive strength 14 and 5 MPa after heating. For titanium cast in phosphate bonded investment, the hardness on its top surface was 655 Hv, the tensile strength was 379 MPa, the elongation was 19.4%, and the surface roughness was 2.29 microm. Athough the thermal expansion of phosphate bonded investment is small, the setting expansion is large enough to compensate for the shrinkage of titanium castings. As its thermal expansion at T >/= 600 degrees C was constant and its heating-cooling cycle was almost reversible, these two properties can reduce the thermal shock and thus avoid cracking of the investment.

Three-dimensional conformal radiotherapy for the treatment of arteriovenous shunting in patients with hepatocellular carcinoma

The objective of this study is to evaluate the efficacy of radiotherapy for the treatment of arteriovenous shunting (AVS) in patients with hepatocellular carcinoma (HCC). Between November 1997 and April 2005, 20 HCC patients with AVS were referred to our department for radiotherapy. The radiation was delivered with 10-15 MV X-ray given 5 days per week at 2 approximately 2.5 Gy per fraction. Total doses ranged from 45 to 64 Gy (median dose 60 Gy). The patients were followed up with color Doppler sonography. When non-invasive imaging suggested obliteration, X-ray angiography was performed to verify the results. Four of the 20 AVS proved to be completely obliterated at X-ray angiography in 1.9, 2.8, 1.8 and 2.9 months after radiotherapy. One of the remaining 16 showed obvious regression on Doppler sonography 0.5 months after radiotherapy, but X-ray angiography was not performed to verify the result. Radiation-related hepatic failure did not occur during the follow-up period. In conclusion, radiotherapy is a treatment alternative for AVS in HCC patients and gives patients with poor prognosis the chance to receive further transcatheter arterial embolization.

Characteristics and predictive factors of early-onset diarrhoea during pelvic irradiation

This study reported characteristics and predictive factors of early-onset diarrhoea in patients receiving pelvic irradiation. We retrospectively reviewed 229 patients undergoing radiotherapy alone for cervical or uterine cancer. Oral barium was taken 90 min before simulation. According to contrast medium within small intestine only or colon in simulation films, we categorised patients as normal and rapid transit groups. Small or large volume of small-bowel was also evaluated according to barium distribution of simulation films. Whole-pelvic irradiation (39.6-45 Gy/22-25 fractions) was delivered to all patients initially. We recorded the onset of diarrhoea during pelvic irradiation. The rates of early-onset diarrhoea (<10 Gy) were compared between these two groups. The incidence of diarrhoea before 10 Gy was 7% and 17% (p = 0.138) in patients with normal and rapid transit, respectively. In multivariate analysis, interaction among rapid transit, prior abdomen operation and large small-bowel volume (p = 0.019) were noted for early-onset diarrhoea. Further subgroup analysis revealed that rapid transit (p = 0.046) was a significant factor in patients with both prior abdominal operation and large small-bowel volume. The incidence of early-onset diarrhoea was as high as 40% in this particular group. Patients experiencing early-onset diarrhoea had a higher incidence of moderate to severe diarrhoea (65%) than those without early-onset diarrhoea (23%) (p<0.001). In multivariate analysis, early-onset diarrhoea was the only factor of moderate to severe diarrhoea (p = 0.001). In conclusion, rapid small-bowel transit may be predisposed to early-onset diarrhoea during pelvic radiotherapy in patients with both prior abdominal operations and large small-bowel volume. Early-onset diarrhoea is considered as a predictive factor of diarrhoea of a higher grade.

Evaluation of different bonded investments for dental titanium casting

The properties of several different investments were investigated including phosphate bonded, magnesia bonded, and alumina cement investments. Measurements included the setting expansion, thermal expansion, and compressive strength of investments, as well as the tensile strength, elongation, Vickers hardness (VHN) and surface roughness of titanium castings. For phosphate bonded investment, the setting expansion after being mixed with its own mixing solution was 2.10%, which was larger than the other investments; the thermal expansion was -0.25% at 200 degrees C, the compressive strength 14 and 5 MPa after heating. For titanium cast in phosphate bonded investment, the hardness on its top surface was 655 Hv, the tensile strength was 379 MPa, the elongation was 19.4%, and the surface roughness was 2.29 microm. Although the thermal expansion of phosphate bonded investment is small, the setting expansion is large enough to compensate for the shrinkage of titanium castings. As its thermal expansion at T > or = 600 degrees C was constant and its heating-cooling cycle was almost reversible, these two properties can reduce the thermal shock and thus avoid cracking of the investment.

Identification of the first nucleated phase in submonolayer Ti deposited on Si(111)-7×7 by atomic resolution techniques

Ti5Si4 has been identified to be the first nucleated phase in submonolayer Ti deposited on the Si(111)-7 x 7 surface by ultrahigh vacuum scanning tunneling microscopy in conjunction with atomic-resolution transmission electron microscopy. The direct observation of the formation of clusters surrounded by the heavily damaged silicon lattice strongly suggested that Si is the dominant diffusing species in forming the silicide.

Methamphetamine-induced conditioned place preference is facilitated by estradiol pretreatment in female mice

Ovarian hormones were well documented to modulate the dopamine release in the central dopaminergic systems. The dopamine-releasing effects in the nucleus accumbens, a major target of the mesolimbicortical dopaminergic system, were closely associated with the reinforcing effects of two psychomotor stimulants, cocaine and methamphetamine. This study aimed to examine the sex differences in the cocaine- and methamphetamine-reinforcing behavior, conditioned place preference. In addition, the modulating effects of estradiol and progesterone on methamphetamine-induced conditioned place preference were investigated in both sexes of adult gonadectomized mice. There was no sex difference in the sensitivity to the cocaine (5 mg/kg)-induced conditioned place preference. However, female mice exhibited a more potent methamphetamine (1 mg/kg)-induced conditioned place preference than did male mice. Moreover, pretreatment with estradiol for two consecutive days before the beginning of the conditioning and throughout the four daily conditionings (0.47 microg/day for totally six days) effectively facilitated methamphetamine-induced conditioned place preference in gonadectomized female mice, but not in gonadectomized male mice. Progesterone, under a similar treatment regimen (0.47 microg/day for six consecutive days), did not alter the methamphetamine-induced conditioned place preference in either sex of gonadectomized mice. Taken together, we conclude that the facilitating effects of estradiol on methamphetamine-induced conditioned place preference could be sex-dependent with an eminent sensitivity associated with the adult female mice.

Motorcycle emissions and fuel consumption in urban and rural driving conditions

This work reports sampling of motorcycle on-road driving cycles in actual urban and rural environments and the development of representative driving cycles using the principle of least total variance in individual regions. Based on the representative driving cycles in individual regions, emission factors for carbon monoxide (CO), hydrocarbons (HC), nitrogen oxides (NO(x)=NO+NO(2)) and carbon dioxide (CO(2)), as well as fuel consumption, were determined using a chassis dynamometer. The measurement results show that the representative driving cycles are almost identical in the three largest cities in Taiwan, but they differ significantly from the rural driving cycle. Irrespective of driving conditions, emission factors differ insignificantly between the urban and rural regions at a 95% confidence level. However, the fuel consumption in urban centers is approximately 30% higher than in the rural regions, with driving conditions in the former usually poor compared to the latter. Two-stroke motorcycles generally have considerably higher HC emissions and quite lower NO(x) emissions than those of four-stroke motorcycles. Comparisons with other studies suggest that factors such as road characteristics, traffic volume, vehicle type, driving conditions and driver behavior may affect motorcycle emission levels in real traffic situations.

A novel splicing acceptor mutation of the factor VIII gene producing skipping of exon 25

A gross deletion in the factor VIII (FVIII) mRNA was determined by reverse transcriptase polymerase chain reaction (RT-PCR) for a patient with moderately severe hemophilia A. Sequencing of the RT-PCR product depicted a 177-bp deletion ranging from nucleotide (nt) 6724 to nt 6900 of FVIII cDNA, exactly corresponding to the whole exon 25. Further study of the genomic DNA revealed the presence of a single base pair substitution (G >A) at position -1 of intron 24. The absolute consensus AG doublet of the intron 24 splicing acceptor changed to AA. In the novel splice site mutation, exon 24 was erroneously spliced to exon 26, skipping exon 25. The FVIII antigen level was normal despite the markedly reduced functional activity. Since exon 25 corresponds to part of the C2 domain, we speculate that for this patient the aberrant C2 domain markedly reduces binding affinity of FVIII protein to the phospholipid membrane, thus severely impairing the protein function.

Impaired gallbladder function in spinal cord injury on quantitative Tc-99m DISIDA cholescintigraphy

BACKGROUND

Patients with spinal cord injury (SCI) have increased prevalences of gallstones and acute acalculous cholecystitis. A possible explanation for the increased prevalence of gallstone disease in SCI patients is decreased gallbladder motility causing gallbladder stasis, a known risk factor for gallstone disease. We investigated gallbladder function in SCI.

METHODS

Twenty-five normal control subjects and 50 SCI patients were included in this study. Gallbladder function was measured by technium 99m-labeled imino-diacetic acid analogue (Tc-99m DISIDA) cholescintigraphy and represented by the filling fraction (FF) and the ejection fraction (EF). The SCI patients were assigned to subgroups: old versus young, female versus male, high- versus low-level injury, and long versus short injury duration.

RESULTS

Forty-two percent of SCI patients had abnormal FFs and 54% of SCI patients had abnormal EFs. Significantly decreased FF and EF values were found in SCI patients, especially in those who were female and had high-level injuries.

CONCLUSION

With the use of quantitative Tc-99m DISIDA cholescintigraphy, we found that SCI can significantly impair gallbladder function.

Expression of epidermal growth factor receptor in head and neck cancers correlates with clinical progression: a multicentre immunohistochemical study in the Asia-Pacific region

AIMS

With ongoing efforts to target the epidermal growth factor receptor (EGFR)-mediated tumour growth in the treatment of selected human malignancies, there is a need to determine the expression levels of EGFR and to evaluate its prognostic value in various malignancies in the Asia-Pacific region.

METHODS AND RESULTS

A total of 172 patients with head and neck squamous cell carcinomas from Australia, Hong Kong, Singapore, and Taiwan were selected for EGFR detection. Immunohistochemical staining was performed to evaluate EGFR expression. EGFR expression was present in 88.4% (152/172) of all cases tested. Specifically, EGFR expression was found in 91.3% (42/46), 84.6% (22/26), 84.1% (37/44), 96.0% (24/25), and 87.1% (27/31) cases of head and neck squamous cell carcinomas from the oral cavity, oropharynx, nasopharynx, hypopharynx, and larynx, respectively. The results demonstrate a stronger EGFR expression in T4 tumours (P=0.017) and later clinical stages (P=0.016). No significant correlation was seen with risk factors, primary tumour site and ethnicity.

CONCLUSIONS

The majority of head and neck squamous cell carcinomas express EGFR, indicating the importance of studying the efficacy of anti-cancer therapy through this pathway. The results also show similar rates of receptor expression in head and neck squamous cell carcinoma patients from our region compared with other parts of the world.

Different role of Apaf-1 in positive selection, negative selection and death by neglect in foetal thymic organ culture

Apoptotic protease-activating factor 1 (Apaf-1) is a component of the apoptosome which is required for the activation of procaspase-9. As Apaf-1 knockout (KO) (Apaf-1-/-) mice die before birth, the role of Apaf-1 during thymic selection was investigated using 5 day foetal thymic organ culture (FTOC) of thymi obtained at gestational day 15. There was a lower ratio of CD4 single-positive (SP) to CD8 SP cells and decreased apoptosis of CD4+CD8+ (DP) thymocytes from Apaf-1-/- mice compared with wild-type. To determine if these defects resulted in increased production of neglected thymocytes, the Apaf-1-/- mice were crossed with the T-cell receptor (TCR)-alpha-chain KO mice. There was no difference in thymocyte development in the thymi of TCR-alpha-/-Apaf-1-/- and TCR-alpha-/-Apaf-1+/+ mice 5 days after FTOC. To determine if Apaf-1 is involved in apoptosis during death by negative or positive selection, FTOC of the thymus of Apaf-1-/- Db/HY TCR-alphabeta transgenic (Tg) mice was carried out. There was decreased apoptosis of the HY clonal-specific M33+ thymocytes and an increased percentage of the autoreactive CD8+M33+ thymocytes in male, but not female Apaf-1-/- Db/HY TCR Tg mice. Our data suggest that Apaf-1 is not involved in positive selection or death by neglect, but may have a partial role in negative selection during early thymic T-cell development.

Predictive factors for skin telangiectasia following post-mastectomy electron beam irradiation

This study evaluated the predictive factors associated with skin telangiectasia following post-mastectomy electron beam irradiation of the chest wall and regional lymph nodes in patients with breast cancer. From July 1987 to December 1994, 120 women with stages II and III breast cancer received electron beam irradiation following modified radical mastectomy. Doses of 50-50.4 Gy per 25-28 fractions were given to the chest wall (with bolus), the internal mammary nodes, the supraclavicular nodes and the axillary lymph nodes using a 12 MeV or 15 MeV single portal electron beam. 19 patients received an additional 10-16 Gy boost to the surgical scar using a 9 MeV electron beam. Univariate and multivariate analyses for the development of skin telangiectasia showed 5- and 7-year actuarial rates of telangiectasia to be 59% and 72%, respectively. In univariate analysis, an additional surgical scar boost (p=0.023) as well as no treatment interruption (p=0.028) were associated with a significantly increased risk of skin telangiectasia. In multivariate analysis, the only significant independent factor for the development of skin telangiectasia was surgical scar boost (p=0.026); no treatment interruption showed a trend but did not achieve significance (p=0.051). Thus, patients given an additional boost to the surgical scar are more likely to develop skin telangiectasia. Shorter treatment courses may result in a higher probability of skin telangiectasia following electron beam irradiation.

Psychiatric morbidity and post-traumatic symptoms among survivors in the early stage following the 1999 earthquake in Taiwan

This study reports the clinical psychiatric presentations and post-traumatic symptoms among 525 survivors at Yu-Chyr District in Nantou County who sought psychiatric service in the first month following the devastating earthquake that struck the central area of Taiwan. All subjects received psychiatric interviews and assessments using the 12-item Chinese Health Questionnaire (CHQ-12) and a checklist for post-traumatic symptoms. The most common psychiatric symptoms reported were insomnia, palpitations, nervousness, and dizziness with headache. Eleven percent of the subjects reported having thought of death or having suicidal ideation. The mean score on the CHQ-12 was 6.43 (S.D.=2.89). The rate of probable psychiatric morbidity as defined by a CHQ-12 score > or =3 was 89.9%. Post-traumatic symptoms were very prevalent, particularly symptoms of re-experiencing the earthquake and hyper-arousal. Factors significantly associated with high psychiatric morbidity were being female, serious destruction of property and house, and personality characteristics of nervousness and obsessiveness. Findings of this study suggest that early psychiatric intervention, including pharmacological treatment for acute stress disorder, is indicated during the early stages following a disastrous earthquake.

Peripheral blood cells among community residents living near nuclear power plants

Information about hematopoieses as a result of exposure to very low levels of radiation is scarce. To investigate the human hematopoietic effect of very low level radiation exposure, measurements of peripheral blood components were performed among 3602 men and women, aged 35 and above, living in a community near two nuclear power installations in Chinshan, Taiwan. The radiation level that each individual was exposed to was represented by a surrogate level, '1/D2(1i) + 1/D2(2i)', a transformed distance from each individual's residence to the two power plants D1 and D2. In addition to comparing average hematology measurements, multiple regression analyses were done to include age, gender, smoking, drinking status and the surrogate radiation exposure level as independent variables. Univariate and bivariate analyses showed that the hematology measurements had significant associations with age, gender, smoking or drinking. The multiple regression analyses revealed that significant positive associations with '1/D2(1i) + 1/D2(2i)' were found for hemoglobin, hematocrit, platelet, white blood cell and red blood cell. The platelet count might increase for 208.7 x 10(3)/microl if the exposure from the nuclear plants increased by one exposure unit. This type of association implies that those who lived closer to the nuclear power installation had a higher blood cell count; we suspect that this could be a type of radiation hormesis.

Influence of CETP gene variation on plasma lipid levels and coronary heart disease: a survey in Taiwan

Cholesteryl ester transfer protein (CETP) transfers cholesteryl ester from high-density lipoprotein (HDL) to very low-density lipoprotein (VLDL), low-density lipoprotein (LDL) and chylomicron in exchange for triglycerides. Two CETP genetic variation and four polymorphisms are investigated by polymerase chain reaction (PCR) and restriction enzyme digestion in a population of Taiwan. The results show that a very rare variation frequency is found for CETP intron 14 splice site G-->A change. The population shows a predominant 405Ile allele (61%), 442Asp (97.7%), intron 1Taq1B(+) G allele (52%), intron 8 Msp1(-) A allele (89%) and intron 9 EcoN1(-) T allele (59.2%) in the control group. Patients with coronary heart disease (CHD) have more CETP EcoN1(+/+) GG genotype (25.3%) than the controls (13.6%) (P=0.049). The intron 1 Taq1B(-) A allele is associated with a high HDL cholesterol and apoA1 level, the EcoN1(+) G allele with a low apoA1 level and the 442Gly with both high total cholesterol and LDL cholesterol levels. Paradoxically, the 442Gly is also present with a higher frequency (5.2%) in HDL cholesterol > or =65 mg/dl group than that in the general population (2.3%) (P=0.04).

Relationships between quality of sleep and its related factors among elderly Chinese immigrants in the Seattle area

The risk factors related to quality of sleep in elderly adults, such as life-style events, physical illness, psychological factors, and gender have been well identified by several studies. However, information regarding the relationship between quality of sleep and its related factors among elderly Chinese immigrants is not available in recent sleep literature. The purposes of this study were to explore the quality of sleep and discover the relationships between sleep quality and its related factors among elderly Chinese immigrants people in the Seattle area. Pearson's correlation and descriptive statistics were used to analyze data. Eighty community-dwelling Chinese elderly people, aged from 66 to 93, were recruited from the Chinese Senior Day Care Center, local Chinese churches, elderly Chinese individuals' private homes, and Chinese retirement apartments within the Seattle area. Three questionnaires were utilized to collect data, and personal interviews were used to facilitate the subjects in completing the questionnaires. The findings of this study showed that (1) 55% (n = 44) of the participants were identified as poor sleepers and 45% (n = 36) as good sleepers. (2) depression and the number of current diseases experienced by the subjects were in statistically significant correlation with quality of sleep, with r = .477, p = .00 and r = .221, p = .049 respectively. (3) daytime napping did not affect nighttime sleep in this study' population. The findings of this study can provide information regarding sleep problems among elderly Chinese immigrants to improve the elderly's quality of sleep.