Racial Discrimination and Health-Related Quality of Life: An Examination Among Asian American Immigrants

OBJECTIVES

We aimed to examine the relationship between everyday and major racial discrimination with health-related quality of life (HRQOL), which consists of self-rated health, days of poor physical health, mental health, and activity limitation.

DESIGN

In a cross-sectional analytic sample of 524 foreign-born Asian adults, aged 18 years and older, we conducted multivariable logistic regression and multivariable negative binomial regression to examine associations between discrimination and HRQOL. Furthermore, potential effect modification was tested by gender, ethnicity, and social support.

RESULTS

Associations were found between everyday racial discrimination and days of poor physical health (incidence rate ratio, IRR = 1.05), mental health (IRR = 1.03), and activity limitation (IRR = 1.05). Stronger significant associations were observed between major racial discrimination and days of poor physical health (IRR = 1.21), mental health (IRR = 1.16), and activity limitation (IRR = 1.53), adjusting for all covariates. Racial discrimination was not associated with poor self-rated health. In addition, gender significantly modified the relationship between continuous racial discrimination and activity limitation days with associations of greater magnitude among men, while social support significantly modified the association between categorized major racial discrimination and physically unhealthy days. When stratified, the association was only significant among those with low social support (IRR = 3.04; 95% CI: 1.60, 5.79) as opposed to high social support.

CONCLUSIONS

This study supports the association between racial discrimination and worse HRQOL among Asian Americans, which can inform future interventions, especially among men and those with low social support, aimed at improving the quality of life in this population.

Application of a likelihood ratio test based method for safety signal detection to left ventricular assist devices

Effective post-market safety surveillance of medical devices is critical for public health. However, many current statistical methods for safety signal detection do not control for type I error when assessing multiple device and adverse event (AE) combinations. This can result in increased false signals, underscoring the need for more robust statistical methods. Moreover, the duration of medical device use can be an important factor to consider in safety surveillance. In this study, we adapted a likelihood ratio test (LRT) based method, which was initially developed and applied to drugs, to identify safety signals for left ventricular assist devices (LVAD). Among patients with chronic, advanced left ventricular failure, we analyzed AE data for HeartWare and HeartMate II patients during a two-year period and further incorporated person-years (henceforth exposure-time). The novel modified LRT and conventional Z-test with p-values adjusted by the Benjamini-Hochberg (BH) procedure were used to explore safety signals by comparing HeartWare and HeartMate II patients in the presence of multiple adverse events. Both methods identified greater incidence of stroke among HeartWare as compared to HeartMate II patients without exposure-time (p = .025 for LRT and p = .027 for Z-test with BH) and with exposure-time (p = .002 for LRT and p = .005 for Z-test with BH). By using improved statistical methods for safety signal detection, potential safety issues can be identified and addressed in a more timely manner to enhance public safety.

The Chinese and Korean American immigrant experience: a mixed-methods examination of facilitators and barriers of colorectal cancer screening

OBJECTIVE

Among Asian Americans, colorectal cancer (CRC) is the second leading cause of cancer deaths. Despite strong evidence that screening can reduce CRC-related mortality, fewer Chinese and Koreans receive screening as compared to non-Hispanic whites and blacks. The objective of this study was to examine facilitators and barriers as well as strategies to promote CRC screening in this population.

DESIGN

This study employed a mixed-methods design. We conducted 17 key informant interviews and 12 focus groups in the Washington, D.C. metropolitan area. 120 Chinese and Korean focus group participants, aged 50 to 85, also provided quantitative data through self-administered surveys. All participants were asked to discuss facilitators and barriers of CRC screening, including in relation to culture.

RESULTS

Participants who had a regular physician and doctor's recommendation for CRC screening were more likely to ever receive a colonoscopy (adjusted odds ratio (aOR) = 3.51; 95% confidence interval (CI): 1.26, 9.79 and aOR = 6.61; 95% CI: 2.63, 16.65, respectively). A doctor's recommendation was also significantly associated with receipt of a fecal occult blood test (FOBT) (aOR = 4.00; 95% CI: 1.43, 11.15). In terms of barriers, those who reported having no time and not having symptoms were less likely to have a colonoscopy (aOR = 0.15; 95% CI: 0.03, 0.82 and aOR = 0.02; 95% CI: 0.002, 0.23, respectively) than those who had time and symptoms. Preventive healthcare was often not viewed as a priority, particularly for those living the'immigrant life,' who gave precedence to work. Cultural barriers to CRC screening included language (e.g. limited English proficiency and low health literacy); fear of finding CRC and burdening the family especially children; fatalism; and stigma towards cancer.

CONCLUSIONS

Future interventions and programs aiming to increase CRC screening among Chinese and Korean Americans should address both cultural and non-cultural factors that influence CRC screening uptake.

Abstract PR02: Randomized controlled trial to increase quality of life and reduce perceived stress among Korean American breast cancer survivors

Background: Despite large increases in breast cancer incidence among Korean women, there have been remarkably few empirical studies to improve survivorship among Korean American breast cancer survivors (KBCS), many of whom experience linguistic and cultural barriers. According to limited research on Asian Americans, KBCS report low quality of life (QOL) and high perceived stress (henceforth referred to as “stress”). To address this gap, we tested the effectiveness of one of the first linguistically appropriate and culturally sensitive cognitive-behavioral stress management programs that was developed to improve QOL and reduce stress in KBCS.

Methods: The TOGETHER (Together Overcome and Get Empowered Through Health Education and Relationships) program consists of seven 2-hour sessions and one follow-up seven weeks post-intervention. These findings are preliminary results based on cycles one to four of the program, consisting of 66 KBCS in the Washington, D.C. metropolitan area of which complete data was available for 61 participants (92.4%). The standard intervention (SI) group (n=28) received linguistically and culturally tailored health information related to breast cancer, while the enhanced intervention (EI) group (n=33) received this and additional information/practice on relaxation, stress reduction techniques, mindfulness, utilizing social support, anger management, and assertiveness training.

Outcomes were measured at baseline, upon completion of the program, and at follow-up. QOL was assessed using the Functional Assessment of Cancer Therapy-Breast (FACT-B), which includes five subscales (physical well-being (PWB), social well-being (SWB), emotional well-being (EWB), functional well-being (FWB), and breast cancer subscale (BCS)), while stress was assessed using the Perceived Stress Scale (PSS). Generalized estimating equation (GEE) models were used to examine program effects on QOL and PSS separately. Moreover, the impact of program site (Maryland vs. Virginia), cycle (one to four), and age (less than 65 vs. 65 and over) on these relationships was assessed.

Results: Randomization was effective in that SI and EI participants were similar in regards to sociodemographic, breast cancer-related, and acculturation variables. Program site and cycle did not impact program effects on QOL and PSS and were thus not included in subsequent models. For QOL, the SI group had better quality of life at baseline (mean FACT-B score: 103.3) compared to the EI group (mean FACT-B score: 100.7). Changes in mean FACT-B, SWB, and FWB scores significantly differed between the SI and EI group from baseline to the end of the program. Specifically, the EI group had a 7.0 unit greater increase in mean FACT-B scores, 2.6 unit greater increase in mean SWB scores, and 2.5 unit greater increase in mean FWB scores from baseline to the end of the program as compared to the SI group on average. For stress, the EI group had a higher level of stress (mean PSS score: 18.82) than the SI group (mean PSS score: 17.25) at baseline. Changes in mean PSS scores significantly differed across time between the SI and EI groups. Those in the EI group had a 2.7 unit greater decrease in mean PSS scores from baseline to the end of the program as compared to those in the SI group on average. For age, those who were less than 65 showed overall decreases in stress from baseline to follow-up, while those 65 and over showed initial decreases from baseline to the end of the program and then increases from the end of the program to follow-up beyond the baseline values.

Conclusions: The TOGETHER program is effective in increasing QOL and reducing stress among KBCS and can potentially be adapted and implemented for other socially or linguistically isolated groups in the U.S.

Citation Format: Sunmin Lee, Mary Y. Jung, Jamie H. Sim. Randomized controlled trial to increase quality of life and reduce perceived stress among Korean American breast cancer survivors. [abstract]. In: Proceedings of the Ninth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2016 Sep 25-28; Fort Lauderdale, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2017;26(2 Suppl):Abstract nr PR02.

Abstract B23: Examining the psychometric properties of the Functional Assessment of Cancer Therapy-Breast (FACT-B) among Korean American breast cancer survivors

Background: The 37-item Functional Assessment of Cancer Therapy-Breast (FACT-B) instrument has been validated and widely used in the literature to assess quality of life (QOL) among women with breast cancer. However, validation of the Korean version was conducted among breast cancer patients in Korea, and most studies in the United States have examined multiethnic samples with typically small numbers of Korean Americans (KA). This study examined the psychometric properties of FACT-B and its five subscales (physical well-being (PWB), social well-being (SWB), emotional well-being (EWB), functional well-being (FWB), and breast cancer subscale (BCS)) in a sample of KA breast cancer survivors.

Methods: Data for this study are from a seven week randomized control trial aiming to increase QOL and reduce perceived stress among KA breast cancer survivors. Participants completed the FACT-B instrument at baseline, end of the program, and 7-weeks post intervention. In this study, baseline assessments of FACT-B were examined from 61 KA women in the Washington, D.C. metropolitan area with stages 0 to IV breast cancer. Participants' ages ranged from 30 to 83 (mean=56.7; SD=10.2). Principal component analysis (PCA) was conducted to examine FACT-B and its subscales. The factor correlation matrix was examined to determine the appropriate rotation method. Internal reliability was assessed using Cronbach's alpha.

Results: Varimax rotation was employed given that factor correlations were mostly less than 0.32, which suggests that the variance between factors do not greatly overlap. The internal reliability of FACT-B in this sample was found to be good (α=.88). Moreover, the internal reliabilities were also good for PWB, SWB, and FWB (α=.85 to .89), but lower for EWB and BCS (α=.69 and α=.67 respectively). In general, these findings are consistent with the literature on White (α=.64-.91), African American (α=.77-.92), and Latina women (α=.72-.91) with breast cancer. Some variations were found between our study on KA women and other literature on breast cancer patients in China, Japan, and Korea. The internal reliability for EWB was lower in KA women (α=.69) as compared to Chinese women (α=.84), Japanese women (α=.74), and women in Korea (α=.79). However, our reliability is the same as that found in the initial FACT-B validation study by Brady et al. (1997) (α=.69). For other subscales, the internal reliabilities were similar or lower than in our sample. The initial PCA with varimax rotation retained 11 factors with eigenvalues above 1. However, 4 factors had only one or two items with factor loadings of at least |0.4|. Thus, 5 factors were specified based on the established number of subscales in the literature.

The only item with a factor loading less than .4 was a question that asked how bothered participants were by hair loss. The low loading may be a result of few participants experiencing hair loss at the time of the survey. Interestingly, an item asking participants about how much they worry about dying had a negative loading even after reverse coding (ℓ=-.48), meaning those who worry more tend to have better QOL. One reason may be that concerns regarding death motivate some individuals to reassess priorities and better allocate their time on things that are more valued and enjoyable.

Conclusions: Our findings were consistent with those from previous studies examining White, African American, and Latina women with breast cancer. In addition, FACT-B and its subscales had similar or higher internal reliabilities in our sample of KA women with breast cancer as compared to breast cancer patients in China, Japan, and Korea, with the exception of EWB. Overall, FACT-B was found to be reliable in our sample of KA breast cancer survivors providing additional support for its use in this population.

Citation Format: Mary Y. Jung, Min Q. Wang, Sunmin Lee. Examining the psychometric properties of the Functional Assessment of Cancer Therapy-Breast (FACT-B) among Korean American breast cancer survivors. [abstract]. In: Proceedings of the Ninth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2016 Sep 25-28; Fort Lauderdale, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2017;26(2 Suppl):Abstract nr B23.

Health Examination Is Not a Priority for Less Acculturated Asian Americans

This study examines the associations between acculturation and three health examination behaviors (physical, dental, and eye exams) among 846 Chinese, Korean, and Vietnamese Americans. The study was part of a randomized, community-based trial on liver cancer prevention that targeted Asian Americans in Washington DC metropolitan area. Acculturation was assessed using Suinn-Lew Asian Self-Identity Acculturation (SL-ASIA) scale, acculturation clusters, and length of stay. Health examination behaviors in the last 2 years were self-reported. Potential confounders such as age, gender, ethnicity, income, marital status, self-rated health status, health insurance, and having a regular physician were adjusted. Increased acculturation was associated with greater receipt of preventive services when acculturation was measured by SL-ASIA and acculturation clusters. Compared to those in the "Asian" cluster, those in the "American" cluster and "bicultural" clusters were more likely to have physical exams (American odds ratio (OR) = 1.83, 95 % confidence interval (CI) 0.99, 3.88; bicultural OR = 1.11; 95 % CI 0.72, 1.70), dental exams (American OR = 1.99, 95 % CI 1.09, 3.65; bicultural OR = 1.83, 95 % CI 1.21, 2.78), and eye exams (American OR = 4.48, 95 % CI 2.67, 7.66; bicultural OR = 1.92, 95 % CI 1.31, 2.81). A gradient was observed in these associations with the American cluster having stronger associations than the bicultural cluster. Interaction was found between acculturation and gender for receipt of a physical exam. Future studies are needed to further explicate how access to health care impacts the association between acculturation and health examinations among Asian Americans.

HCV Screening Behaviors and Infection Status among Vietnamese Americans

OBJECTIVES

The aim of this study was to identify socio-economic and acculturation factors associated with hepatitis C (HCV) screening and infection among US Vietnamese Americans.

METHODS

Participants were recruited from 7 Vietnamese community-based organizations in Pennsylvania and New Jersey. The analysis ultimately included 309 participants who participated in a HCV education intervention program.

RESULTS

Overall, 82.5% (255 of 309) intervention participants completed HCV screening over the 6 months prior to the post-intervention assessment. In multivariate-adjusted analysis, participants who lived in Vietnam for 40 years versus 20 years were more likely to receive HCV screening; unemployed individuals were less likely to receive HCV screening than employed people. Among screened participants, 7.5% had HCV infection.

CONCLUSIONS

These findings will guide future culturally and linguistically appropriate interventions to reduce HCV infection and HCV-related liver cancer.

Acculturation and cancer screening among Asian Americans: role of health insurance and having a regular physician

Cancer is the leading cause of death among Asian Americans, but screening rates are significantly lower in Asians than in non-Hispanic Whites. This study examined associations between acculturation and three types of cancer screening (colorectal, cervical, and breast), focusing on the role of health insurance and having a regular physician. A cross-sectional study of 851 Chinese, Korean, and Vietnamese Americans was conducted in Maryland. Acculturation was measured using an abridged version of the Suinn-Lew Asian Self-Identity Acculturation Scale, acculturation clusters, language preference, length of residency in the US, and age at arrival. Age, health insurance, regular physician, gender, ethnicity, income, marital status, and health status were adjusted in the multivariate analysis. Logistic regression analysis showed that various measures of acculturation were positively associated with the odds of having all cancer screenings. Those lived for more than 20 years in the US were about 2-4 times [odds ratio (OR) and 95 % confidence interval (CI) colorectal: 2.41 (1.52-3.82); cervical: 1.79 (1.07-3.01); and breast: 2.11 (1.25-3.57)] more likely than those who lived for less than 10 years to have had cancer screening. When health insurance and having a regular physician were adjusted, the associations between length of residency and colorectal cancer [OR 1.72 (1.05-2.81)] was reduced and the association between length of residency and cervical and breast cancer became no longer significant. Findings from this study provide a robust and comprehensive picture of AA cancer screening behavior. They will provide helpful information on future target groups for promoting cancer screening.

Acute basilar artery occlusion: outcome of mechanical thrombectomy with Solitaire stent within 8 hours of stroke onset

BACKGROUND AND PURPOSE

Mechanical thrombectomy with a stent retriever applied shortly after symptom onset could increase good functional outcomes and improve survival in patients with acute basilar artery occlusion, but this has not yet been studied. This study evaluated the efficacy and safety of mechanical thrombectomy with a Solitaire stent within 8 hours of stroke onset in patients with acute basilar artery occlusion.

MATERIALS AND METHODS

We analyzed 25 consecutive patients with acute basilar artery occlusion who were treated with mechanical thrombectomy by use of the Solitaire stent within 8 hours of stroke symptom onset. Successful recanalization was defined as TICI grade 2b or 3. Good outcome was defined as mRS score of 0-2 at 3 months. Clinical and radiologic data in patients with good outcomes were compared with those with poor outcomes.

RESULTS

Successful recanalization was achieved in 96% (24/25) of patients, and 48% (12/25) of patients had good outcomes. Eighty-eight percent (22/25) of patients survived to 3 months. The median NIHSS score on admission was significantly lower in patients with good outcomes than in those with poor outcomes (9.5 versus 14, P = .005). Procedure-related complications occurred in 2 patients (8%). No symptomatic intracerebral hemorrhages occurred.

CONCLUSIONS

The current study suggests that mechanical thrombectomy by use of a Solitaire stent within 8 hours of stroke onset increases good outcomes and improves survival in patients with acute basilar artery occlusion.

Inhibition of adipogenesis in 3T3-L1 cells and suppression of abdominal fat accumulation in high-fat diet-feeding C57BL/6J mice after downregulation of hyaluronic acid

OBJECTIVE

Adipogenesis can be spatially and temporally regulated by extracellular matrix (ECM). We hypothesized that the regulation of hyaluronic acid (HA), a component of the ECM, can affect adipogenesis in fat cells. The effects of HA on adipogenesis were investigated in vitro in 3T3-L1 cells and in vivo in high-fat diet-feeding C57BL/6J mice.

METHODS

We investigated the effects of HA by degradation of pre-existing or synthesized HA and artificial inhibition of HA synthesis in adipogenesis.

RESULTS

In vitro adipogenesis in 3T3-L1 cells was inhibited by treating them with exogenous hyaluronidase (HYAL) and with 4-methylumbelliferone, which inhibited the synthesis of HA in a concentration-dependent manner. In vivo, abdominal fat accumulation in high-fat diet-feeding C57BL/6J mice was suppressed by exogenous HYAL 10(4) IU injections, which was associated with reduction of lipid accumulation in liver and increase of insulin sensitivity.

CONCLUSION

Changes in the ECM such as accumulation of high molecular weight of HA by HAS and degradation of HA by endogenous HYAL were essential for adipogenesis both in vitro and in vivo.

Characterization and quantification of anthocyanins in grape juices obtained from the grapes cultivated in Korea by HPLC/DAD, HPLC/MS, and HPLC/MS/MS

The characterization and quantification of anthocyanins in grape cultivars of Oll-Meoru (Vitis coignetiaexVitis labrusca), Neut-Meoru (Vitis coignetiaexVitis labrusca), Muscal Bailey A. (Vitis labruscana), and Campbell Early (Vitis labruscaxV. vinifera) cultivated in Korea were carried out by partial purification through XAD-7 column chromatography followed by C-18 HPLC/diode array detector (DAD), HPLC/MS, and HPLC/MS/MS analyses. The column oven temperature during the reverse phase C-18 HPLC greatly affected the separation of individual anthocyanins. The result showed that the optimum column oven temperature was 35 degrees C. Sixteen different anthocyanins (11 nonacylated and 5 acylated anthocyanins) were identified in the grape juices. Oll-Meoru, Neut-Meoru, and Muscat Bailey A (MBA) grape juices contained only nonacylated anthocyanins. Oll-Meoru and Neut-Meoru grape juices had same anthocyanins, but their proportions were considerably different. Peonidin 3,5-diglucoside and malvidin 3,5-diglucoside were the major anthocyanins in Oll-Meoru grape juice. Delphinidin 3-glucoside was, however, the major anthocyanin in Neut-Meoru grape juice. Peonidin 3-glucoside and malvidin 3-glucoside were the most abundant anthocyanins in Muscal Bailey A grape juice. Campbell Early grape juice contained both nonacylated and acylated anthocyanins. Cyanidin 3-(p-coumaroyl)glucoside-5-glucoside and peonidin 3-(p-coumaroyl)glucoside-5-glucoside were the most abundant anthocyanins in Campbell Early grape juice. Total anthocyanin contents were greatly different in different grape jucies, with the highest in Neut-Meoru juice (1043.5 microg/mL), followed by Oll-Meoru (997.7 microg/mL), MBA (390.2 microg/mL), and Campbell Early (183.9 microg/mL) juices. The total anthocyanin content in Neut-Meoru grape juice was 5.67 times higher than that in Campbell Early grape juice. This represents the 1st report on the systematic characterization and quantification of anthocyanins in the juices of these grapes cultivated in Korea.

Technical Note: Improved Extraction Method with Hexane for Gas Chromatographic Analysis of Conjugated Linoleic Acids

Extraction properties of different solvents (chloroform/methanol, hexane/isopropanol, and hexane) were studied for the gas chromatographic analysis of conjugated linoleic acids (CLA) from probiotic bacteria grown in de Man, Rogosa, and Sharpe medium. As compared with chloroform/methanol and hexane/isopropanol, hexane showed comparable extraction efficiency for CLA from unspent de Man, Rogosa, and Sharpe medium, but showed minimal extraction of oleic acid originated from the emulsifier in broth. The extraction efficiency of CLA by hexane was influenced by the broth pH, showing the optimal pH of 7.0. Repeated extraction with hexane increased the yield. Extraction with hexane showed excellent recovery of spiked CLA from the spent broth with up to 97.2% (standard deviation of 1.74%). This represents the highest recovery of CLA from culture broth ever reported. The sample size was also successfully reduced to 0.5 mL to analyze CLA from the broth without impairment of analytical data. This smaller sample size in the 1.5-mL microcentrifuge tube using a small bench-top centrifuge reduced analytical time significantly.

Estimating geriatric patient's body weight using the knee height caliper and mid-arm circumference in Hong Kong Chinese

The use of the knee height caliper is a convenient way to estimate a patient's body weight. However, the equation devised to estimate an individual's body weight was specifically designed for Caucasians and Blacks. Therefore, this study is to assess the suitability of the knee height caliper among Chinese geriatric patients residing in Hong Kong. Over a six-month period, all geriatric patients from an acute care hospital and private nursing home in the Kwun Tong were recruited into the study. Only patients/residents that were considered unstable with ascites; low blood pressure; on cardiac monitors or had respiratory difficulties were excluded. Measurements from the knee height caliper and mid-arm muscle circumference of the patients were necessary for estimating their body weights. The actual body weights measured with calibrated bed, chair or portable scales was compared with the calculated body weights from the equation. A comparison of the mean and linear regression was performed for analysis of the results. A total of 300 geriatric patients (200 females and 100 males) were recruited. The mean MAC and knee height results were as follows: 25.1 cm (SD 3.9) for females and 26.2 cm (SD 3.2) for males; and 45.75 cm (SD 2.09) for females and 48.98 cm (SD 2.09) for males respectively. The mean difference among the male group was 0.4222 (95% CI: -0.54, 1.39) with a mean estimated body weight of 58.1 kg (SD 10.1) and a mean actual body weight of 57.7 kg (SD 9.9). The mean difference among the female group was 2.9649 (95% CI: 2.30, 3.63) with a mean estimated body weight of 51.6 kg (SD 10.9) and a mean actual body weight of 48.6 kg (SD 10.1). A new equation devised from the data is as follows: Chinese males (over 60 years of age) (R-square -0.81) Weight = [knee height (cm) x 0.928 + mid-arm circumference (cm) x 2.508 - age (years) x 0.144] - 42.543 +/-9.9kg of actual weight for 95% of Chinese males; Chinese females (over 60 years of age) (R-square - 0.82) Weight (kg) = [knee height (cm) x 0.826 + mid-arm circumference (cm) x 2.116 - age (years) x 0.133] - 31.486 +/-10.1kg of actual weight for 95% of Chinese females. The results showed that the mean estimated body weight calculated from the knee height equation (for Caucasians) was significantly larger than the mean actual body weight for the Chinese subjects. This study suggests that the knee height caliper is a useful tool for estimating the body weights. However, a multi-center study is necessary to validate the new equation for the elderly Chinese population.

The in vitro effects of dehydroepiandrosterone on human osteoarthritic chondrocytes

OBJECTIVE

To investigate the in vitro effects of dehydroepiandrosterone (DHEA) on human osteoarthritic chondrocytes.

DESIGN

Chondrocytes isolated from human osteoarthritic knee cartilage were three-dimensionally cultured in alginate beads, except for cell proliferation experiment. Cells were treated with DHEA in the presence or absence of IL-1beta. The effects on chondrocytes were analyzed using a 3-(4,5-dimethylthiazol-2yl)-5-(3-carboxymethoxy-phenyl)-2-(4-sulfophenyl)-2H-tetrazolium inner salt (MTS) assay (for chondrocyte proliferation), a dimethylmethylene blue (DMB) assay (for glycosaminoglycan (GAG) synthesis), and an indole assay (for DNA amount). Gene expressions of type I and II collagen, metalloproteinase-1 and -3 (MMP-1 and -3), and tissue inhibitor of metalloproteinase-1 (TIMP-1) as well as the IL-1beta-induced gene expressions of MMP-1 and -3 were analyzed by reverse transcription-polymerase chain reaction (RT-PCR). The protein synthesis of MMP-1 and -3 and TIMP-1 was determined by Western blotting.

RESULTS

The treatment of chondrocytes with DHEA did not affect chondrocyte proliferation or GAG synthesis up to 100 micro M of concentration. The gene expression of type II collagen increased in a dose-dependent manner, while that of type I decreased. DHEA suppressed the expression of MMP-1 significantly at concentrations exceeding 50 micro M. The gene expression of MMP-3 was also suppressed, but this was without statistical significance. The expression of TIMP-1 was significantly increased by DHEA at concentrations exceeding 10 micro M. The effects of DHEA on the gene expressions of MMP-1 and -3 were more prominent in the presence of IL-1beta, in which DHEA suppressed not only MMP-1, but also MMP-3 at the lower concentrations, 10 and 50 micro M, respectively. Western blotting results were in agreement with RT-PCR, which indicates that DHEA acts at the gene transcription level.

CONCLUSIONS

Our study demonstrates that DHEA has no toxic effect on chondrocytes up to 100 micro M of concentration and has an ability to modulate the imbalance between MMPs and TIMP-1 during OA at the transcription level, which suggest that it has a protective role against articular cartilage loss.

Chemopreventive allylthiopyridazine derivatives induce apoptosis in SK-Hep-1 hepatocarcinoma cells through a caspase-3-dependent mechanism

Dietary organosulphur compounds including diallylsulphide, a component of garlic oil, were shown to inhibit the proliferation of tumour cells. Since hepatocellular carcinoma is one of the most lethal malignancies and there is no effective preventive measure to date, we wished to pursue the chemopreventive potential of the synthetic allylthiopyridazine derivatives (K compounds) on hepatocarcinoma cells. Here, we report that the K compounds efficiently inhibited SK-Hep-1 cell proliferation through induction of apoptosis. Increased chain length at the 3-position of allylthiopyridazine ring improved the potency of growth inhibition. K compounds downregulated Bcl-2, while Bax remained unchanged, reducing the ratio of Bcl-2 to Bax. We also provide evidence that the K compound-induced apoptosis involves cytochrome c release and caspase-3 activation. These results suggest that the allythiopyridazine derivatives, especially 3-propoxy-6-allylthiopyridazine, induce apoptosis in SK-Hep-1 cells through a caspase-3-dependent mechanism, which may contribute to the chemopreventive function for hepatocellular carcinoma.

Effects of temperature and agitation rate on the formation of conjugated linoleic acids in soybean oil during hydrogenation process

The effects of hydrogen temperature and agitation rate on the formation of total conjugated linoleic acids (CLA) and CLA isomers were studied during hydrogenation with a selective Ni catalyst. The CLA isomers were identified by using a 100-m cyano-capillary column gas chromatograph and a silver ion-impregnated HPLC. Reaction temperature and agitation rate greatly affected the quantities of total CLA and individual CLA isomers, and the time to reach the maximum quantity of CLA in the partially hydrogenated soybean oil. As the hydrogenation temperature increased, the maximum quantity of CLA in soybean oil increased, but the time to reach the maximum CLA content decreased. By increasing the hydrogenation temperature from 170 to 210 degrees C, the quantity of CLA obtained was about 2.6 times higher. As the agitation rate decreased, the CLA formation in soybean oil increased, and the time to reach the maximum CLA content also increased. The maximum CLA contents in soybean oil obtained during hydrogenation at 210 degrees C with agitation rates of 300, 500, and 700 rpm were 162.82, 108.62, and 66.15 mg total CLA/g oil, respectively. The present data showed that it is possible to produce high-CLA-content soybean oil without major modification of fatty acid composition by short-time (10 min) selective hydrogenation under high temperature and low agitation rate conditions.

Capsaicin-induced apoptosis in SK-Hep-1 hepatocarcinoma cells involves Bcl-2 downregulation and caspase-3 activation

Hepatocellular carcinoma is one of the most lethal malignancies and there is no effective preventive measure in this highly malignant disease to date. In the present study, we investigated the chemopreventive potential of capsaicin (8-methyl-N- vanillyl-6-nonenamide), the principal pungent ingredient found in hot red pepper, in SK-Hep-1 hepatocellular carcinoma cells. Treatment of capsaicin inhibited growth of SK-Hep-1 cells in a concentration-dependent manner while 4-methoxy capsaicin (Met-capsaicin) was less potent. This inhibitory effect of capsaicin on SK-Hep-1 cell growth was mainly due to the induction of apoptosis as evidenced by DNA fragmentation and nuclear condensation. Furthermore, capsaicin prominently reduced the ratio of anti-apoptotic Bcl-2 to pro-apoptotic Bax and consequently increased caspase-3 activity. These results demonstrate that capsaicin efficiently induced apoptosis in SK-Hep-1 cells through a caspase-3-dependent mechanism, which may contribute to its chemopreventive function.

Inhibitory activity of berberine on DNA strand cleavage induced by hydrogen peroxide and cytochrome c

The inhibitory activity of berberine on the DNA single-strand cleavage induced by hydrogen peroxide and cytochrome c was measured. Berberine effectively inhibited single-strand cleavage of DNA and its effectiveness was concentration-dependent. As the berberine concentration increased, the inhibitory activity against the DNA single-strand cleavage increased. The treatments with 1, 5, 10, 50, and 100 microM berberine showed 7.7, 10.8, 32.2, 39.5, and 51.6% inhibition of DNA cleavage. This inhibitory activity of berberine against the DNA single-strand cleavage has never been reported previously. The inhibitory activity of berberine against DNA cleavage was stronger than caffeic acid and ascorbic acid. Berberine did not show strong hydroxyl radical scavenging activity, but showed strong superoxide anion radical quenching ability.

Targeted disruption of the dopamine D(2) and D(3) receptor genes leads to different alterations in the expression of striatal calbindin-D(28k)

The present study used mice deficient for dopamine D(2) and D(3) receptors to test whether the expression of these two members of the D(2) class of receptors is essential for the normal expression of three markers that characterize the neurochemical differentiation of the striatum: the calcium-binding protein calbindin, tyrosine hydroxylase and acetylcholinesterase. Results from these experiments revealed that the expression of striatal tyrosine hydroxylase (the rate-limiting enzyme of dopamine synthesis) and acetylcholinesterase is unaffected even by the combined knockout of D(2) and D(3) receptors. However, D(2) and D(3) receptor knockouts differently affect the striatal expression of calbindin-D(28k) immunoreactivity. Prominent changes in the cellular distribution of calbindin are detected in striatal neurons of D(2) mutant mice. Whereas calbindin immunolabeling of wild-type neurons is prominent in the nuclei and the cytoplasm of medium spiny neurons, in D(2) mutant mice, calbindin immunoreactivity is concentrated exclusively in the cytoplasmic rim of these neurons. Such changes in the cellular distribution of calbindin expression are not detected in mice lacking D(3) receptors. In these mutants, however, a lesser density of calbindin-immunoreactive neuropil is detected in the ventral portions of the striatum, i.e. in regions in which D(3) receptors are thought to be expressed at highest levels. Mice lacking both D(2) and D(3) receptors show both phenotypes. The altered cellular distribution of calbindin in D(2) mutants is likely to have functional consequences for some of the Ca(2+)-mediated cellular functions. The topography of the decreased density of striatal calbindin immunorectivity in D(3) mutants suggests a role for D(3) receptors in supporting the expression of striatal calbindin. The observation that mice lacking both D(2) and D(3) receptors show a combination of the D(2) and D(3) mutant phenotypes indicates that each of the different phenotypes detected in the single mutants is indeed related to the lack of the two different D(2)-like receptor subtypes.

Improvement of oxidative stability of conjugated linoleic acid (CLA) by microencapsulation in cyclodextrins

Oxidative stability of conjugated linoleic acid (CLA) encapsulated in alpha-, beta-, and gamma-cyclodextrins (designated CLA/CDs microencapsules) was studied by measuring the headspace-oxygen depletion in airtight serum bottles and by measuring the peroxide values (POV). The rate of oxygen depletion was reduced from 41.0 (control) to 21.5, 2.1, 1.2, and 1.1 micromol/L.h(-)(1) by CLA/alpha-CD microencapsules at 1:1, 1:2, 1:4, and 1:6 mole ratios, respectively, indicating that CLA oxidation was completely protected by a 1:4 mole ratio of CLA/alpha-CD. Such a protective effect by CLA/beta-CD or CLA/gamma-CD microencapsules was achieved at a 1:6 mole ratio, but the effect by CLA/beta-CD was slightly greater than that by CLA/gamma-CD. The protective effect of alpha-, beta-, and gamma-CDs for CLA oxidation was confirmed by their POV-reducing abilities in CLA/CDs. These results suggest that alpha-CD was the most effective for the protection of CLA oxidation by microencapsulation, followed by beta-CD and gamma-CD.

Riboflavin-sensitized photochemical changes in beta-lactoglobulin in an aqueous buffer solution as affected by ascorbic acid

The effects of ascorbic acid on the riboflavin-sensitized photochemical changes in beta-lactoglobulin in an aqueous buffer solution as determined by high performance gel permeation liquid chromatography (HPGPLC), insoluble protein content, and individual amino acid content during fluorescent light illumination were studied. The riboflavin-sensitized photochemical degradation of beta-lactoglobulin was effectively inhibited by ascorbic acid, and its inhibitory effectiveness was concentration dependent. The 0.1% ascorbic acid treatment showed 74.4% inhibition of beta-lactoglobulin degradation as determined by a HPGPLC during 6 h light illumination. Insolubility of beta-lactoglobulin in a buffer solution during light illumination was also effectively decreased by ascorbic acid treatment. The riboflavin-sensitized photochemical reduction of cysteine, histidine, lysine, methionine, and tryptophan in beta-lactoglobulin was high during 6 h fluorescent light illumination. The 0.1% ascorbic acid treatment exhibited 20.8% inhibition of total amino acid degradation in beta-lactoglobulin during 6 h light illumination, showing strong inhibitory activity against the degradation of arginine, aspartic acid, cystein, glycine, histidine, phenylalanine, proline, serine, and tryptophan.

Antiphotooxidative activity of protoberberines derived from Coptis japonica makino in the chlorophyll-sensitized photooxidation of oil

Antiphotooxidative components were isolated from the methanolic extract of Coptis japonica Makino by liquid-liquid partitioning fractionation, subsequent column chromatography on Sephadex LH-20 and silica gel, and preparative silica gel TLC. The isolated compounds were identified as coptisine, jatrorrizhine, berberine, and magnoflorine by a combination of spectroscopic studies using UV-visible, IR, mass-spectrometry, and NMR. Coptisine, jatrorrizhine, and berberine isolated from Coptis japonica Makino showed strong antiphotooxidative activity in the chlorophyll-sensitized photooxidation of linoleic acid. However, these compounds did not show either inhibitory activity against lipid peroxidation in rat liver microsomes nor DPPH radical scavenging activity, indicating that their antiphotooxidative activity was not due to the radical chain reaction breaking ability but due to singlet oxygen quenching activity. Commercially available authentic protoberberines (berberine chloride and palmatine chloride) also showed strong antioxidative activity in the chlorophyll-sensitized photooxidation of linoleic acid. The antiphotooxidative activities of the berberine chloride and palmatine chloride were significantly higher than that of ascorbyl palmitate in the chlorophyll-sensitized photooxidation of linoleic acid. These results clearly showed for the first time the antiphotooxidative properties of protoberberines in chlorophyll-sensitized photooxidation of oil.

Decreased c-fos responses to dopamine D(1) receptor agonist stimulation in mice deficient for D(3) receptors

The acute administration of dopamine D(1) receptor agonists induces the expression of the immediate early gene c-fos. In wild type mice, this induction is completely abolished by pretreatment with the D(1)-selective antagonist SCH23390, and pretreatment with the D(2)-like receptor antagonist eticlopride reduces the levels of c-fos expressed in response to D(1) receptor stimulation. Mice deficient for the dopamine D(3) receptor express levels of D(1) agonist-stimulated c-fos immunoreactivity that are lower than c-fos levels of their wild type littermates. Moreover, the acute blockade of D(2) receptors in D(3) mutant mice further reduces c-fos expression levels. These data indicate that the basal activity of both D(2) and D(3) receptors contributes to D(1) agonist-stimulated c-fos responses. The findings therefore indicate that not only D(2) but also D(3) receptors play a role in dopamine-regulated gene expression.

Potentiation of the D2 mutant motor phenotype in mice lacking dopamine D2 and D3 receptors

Within the D2-class of dopamine receptors, the D2 and D3 subtypes share the highest degree of similarity in their primary structure. However, the extent to which these two receptor subtypes have similar or different functional properties is unclear. The present study used gene targeting to generate mice deficient for D2, D3, and D2/D3 receptors. A comparative analysis of D2 and D3 single mutants and D2/D3 double mutants revealed that D2/D3 double mutants develop motor phenotypes that, although qualitatively similar to those seen in D2 single mutants, are significantly more severe. Furthermore, increased levels of the dopamine metabolites dihydroxyphenyl acetic acid and homovanillic acid are found in the dorsal striatum of D2 single mutants. The levels of these metabolites, however, are significantly higher in mice lacking D2 and D3 receptors. In addition, results of immunoprecipitation experiments revealed that D2 single mutants express higher levels of D3 receptor proteins during later stages of their postnatal development. These results suggest that D3 receptors compensate for some of the lacking D2 receptor functions and that these functional properties of D3 receptors, detected in mice with a D2 mutant genetic background, remain masked when the abundant D2 receptor is expressed.

Effects of roasting on pyrazine contents and oxidative stability of red pepper seed oil prior to its extraction

Red pepper seeds were roasted with constant stirring for 6, 9, 10, and 12 min at 210 degrees C, and oils were extracted from the roasted red pepper seeds using an expeller. The iodine values and fatty acid compositions of red pepper seed oils did not change with roasting time. The fatty acid composition of the oil obtained from the red pepper seeds roasted for 6 min was 0.24% myristic acid, 13. 42% palmitic acid, 0.33% palmitoleic acid, 2.07% stearic acid, 10. 18% oleic acid, 73.89% linoleic acid, and 0.37% linolenic acid, showing a fatty acid composition similar to that of high-linoleate safflower oil. Thirteen alkylpyrazines were identified in the roasted red pepper seed oils: 2-methylpyrazine, 2,5-dimethylpyrazine, 2,6-dimethylpyrazine, 2-ethylpyrazine, 2-ethyl-6-methylpyrazine, 2-ethyl-5-methylpyrazine, trimethylpyrazine, 2,6-diethylpyrazine, 2-ethyl-3,5-dimethylpyrazine, tetramethylpyrazine, 2, 3-diethyl-5-methylpyrazine, 2-isobutyl-3-methylpyrazine, and 3, 5-diethyl 2-methylpyrazine. The pyrazine content increased markedly as the roasting time increased, showing 2.63, 5.01, 8.48, and 13.10 mg of total pyrazine/100 g of oils from the red pepper seeds roasted for 6, 8, 10, and 12 min, respectively, at 210 degrees C. 2, 5-Dimethylpyrazine in the roasted red pepper seed oil seemed to be the component most responsible for the pleasant nutty aroma of the oils. The oxidative stabilities of oils increased greatly as the roasting time increased.

Conjugated linoleic acid isomers in partially hydrogenated soybean oil obtained during nonselective and selective hydrogenation processes

Partially hydrogenated soybean oil samples were collected during selective and nonselective hydrogenation processes. The formation of conjugated linoleic acids (CLAs) during hydrogenation was greatly dependent on the types and duration of hydrogenation processes. During hydrogenation processes, CLA contents increased initially. After reaching maximum CLA content, the content decreased during hydrogenation. Selective hydrogenation was much more favorable for the formation of conjugated linoleic acids. With nonselective hydrogenation process, the total CLA content was a maximum (9.06 mg total CLA/g oil) at 35 min. However, with the selective hydrogenation process, the total CLA content was a maximum (98.27 mg total CLA/g oil) at 210 min. The CLA contents in some of the tested selectively hydrogenated soybean oils were among the highest ever reported in foods.

Effects of Ascorbic Acid on the Light-Induced Riboflavin Degradation and Color Changes in Milks

Effects of ascorbic acid (0.025, 0.05, and 0.1%, w/v) on the light-induced riboflavin degradation and color changes in whole and skim milks were studied during 10 h fluorescent light illumination at 7 +/- 2 degrees C. As the time of light illumination increased, the riboflavin content in milks greatly decreased, resulting in 30.1 and 59.1% reduction of riboflavin in whole milk and skim milk after 10 h exposure to fluorescent light, respectively. The ascorbic acid treatment effectively protected the photodegradation of riboflavin in both whole milk and skim milk, and its effectiveness is concentration dependent. The 0.1% ascorbic acid treatments resulted in 50.0 and 25.5% inhibition of riboflavin reduction in whole milk and skim milk after 10 h fluorescent light illumination, respectively. The color parameters of lightness (L), greenness (-a), and yellowness (b) in both whole milk and skim milk decreased after light illumination. Ascorbic acid treatment also protected effectively the changes in greenness and yellowness in both milks during the light illumination.

Proteolytic processing is required for viral superantigen activity

The mouse mammary tumor virus-7 superantigen (vSAG7) is proteolytically processed in B cells at as many as three positions. Proteolytic processing appears to be important for superantigen activity because a processed form of vSAG7 was predominant among those forms that were found to bind to major histocompatibility complex class II molecules. To determine the functional significance of proteolytic processing, a mutation was introduced in vSAG7 at one of the sites where proteolytic cleavage is thought to take place in B cells. Elimination of the putative processing site at position 171 abrogated detectable vSAG7 surface expression in B cells, indicating that proteolytic processing is required for vSAG7 function. Coexpression in insect cells of vSAG7 and furin, a proprotein-processing enzyme, also demonstrated that furin could process vSAG7 at position 171.