[Mitigating metal artifacts from cobalt-chromium alloy crowns in cone-beam CT images through deep learning techniques]

Objective: To develop and evaluate metal artifact removal systems (MARS) based on deep learning to assess their effectiveness in removing artifacts caused by different thicknesses of metals in cone-beam CT (CBCT) images. Methods: A full-mouth standard model (60 mm×75 mm×110 mm) was three-dimensional (3D) printed using photosensitive resin. The model included a removable and replaceable target tooth position where cobalt-chromium alloy crowns with varying thicknesses were inserted to generate matched CBCT images. The artifacts resulting from cobalt-chromium alloys with different thicknesses were evaluated using the structural similarity index measure (SSIM) and peak signal-to-noise ratio (PSNR). CNN-MARS and U-net-MARS were developed using a convolutional neural network and U-net architecture, respectively. The effectiveness of both MARSs were assessed through visualization and by measuring SSIM and PSNR values. The SSIM and PSNR values were statistically analyzed using one-way analysis of variance (α=0.05). Results: Significant differences were observed in the range of artifacts produced by different thicknesses of cobalt-chromium alloys (all P<0.05), with 1 mm resulting in the least artifacts. The SSIM values for specimens with thicknesses of 1.0, 1.5, and 2.0 mm were 0.916±0.019, 0.873±0.010, and 0.833±0.010, respectively (F=447.89, P<0.001). The corresponding PSNR values were 20.834±1.176, 17.002±0.427, and 14.673±0.429, respectively (F=796.51, P<0.001). After applying CNN-MARS and U-net-MARS to artifact removal, the SSIM and PSNR values significantly increased for images with the same thickness of metal (both P<0.05). When using the CNN-MARS for artifact removal, the SSIM values for 1.0, 1.5 and 2.0 mm were 0.938±0.023, 0.930±0.029, and 0.928±0.020 (F=2.22, P=0.112), while the PSNR values were 30.938±1.495, 30.578±2.154 and 30.553±2.355 (F=0.54, P=0.585). When using the U-net-MARS for artifact removal, the SSIM values for 1.0, 1.5 and 2.0 mm were 0.930±0.024, 0.932±0.017 and 0.930±0.012 (F=0.24, P=0.788), and the PSNR values were 30.291±0.934, 30.351±1.002 and 30.271±1.143 (F=0.07, P=0.929). No significant differences were found in SSIM and PSNR values after artifact removal using CNN-MARS and U-net-MARS for different thicknesses of cobalt-chromium alloys (all P>0.05). Visualization demonstrated a high degree of similarity between the images before and after artifact removal using both MARS. However, CNN-MARS displayed clearer metal edges and preserved more tissue details when compared with U-net-MARS. Conclusions: Both the CNN-MARS and U-net-MARS models developed in this study effectively remove the metal artifacts and enhance the image quality. CNN-MARS exhibited an advantage in restoring tissue structure information around the artifacts compared to U-net-MARS.

[Mitigating metal artifacts in cone-beam CT images through deep learning techniques]

Objective: To develop and evaluate metal artifact removal systems (MARSs) based on deep learning to assess their effectiveness in removing artifacts caused by different thicknesses of metals in cone-beam CT (CBCT) images. Methods: A full-mouth standard model (60 mm×75 mm×110 mm) was three-dimensional (3D) printed using photosensitive resin. The model included a removable and replaceable target tooth position where cobalt-chromium alloy crowns with varying thicknesses were inserted to generate matched CBCT images. The artifacts resulting from cobalt-chromium alloys with different thicknesses were evaluated using the structural similarity index measure (SSIM) and peak signal-to-noise ratio (PSNR). CNN-MARS and U-net-MARS were developed using a convolutional neural network and U-net architecture, respectively. The effectiveness of both MARSs were assessed through visualization and by measuring SSIM and PSNR values. The SSIM and PSNR values were statistically analyzed using one-way analysis of variance (α=0.05). Results: Significant differences were observed in the range of artifacts produced by different thicknesses of cobalt-chromium alloys (all P<0.05), with 1 mm resulting in the least artifacts. The SSIM values for specimens with thicknesses of 1.0 mm, 1.5 mm, and 2.0 mm were 0.916±0.019, 0.873±0.010, and 0.833±0.010, respectively (F=447.89, P<0.001). The corresponding PSNR values were 20.834±1.176, 17.002±0.427, and 14.673±0.429, respectively (F=796.51, P<0.001). After applying CNN-MARS and U-net-MARS to artifact removal, the SSIM and PSNR values significantly increased for images with the same thickness of metal (both P<0.05). When using the CNN-MARS for artifact removal, the SSIM values for 1.0, 1.5 and 2.0 mm were 0.938±0.023, 0.930±0.029, and 0.928±0.020 (F=2.22, P=0.112), while the PSNR values were 30.938±1.495, 30.578±2.154 and 30.553±2.355 (F=0.54, P=0.585). When using the U-net-MARS for artifact removal, the SSIM values for 1.0, 1.5 and 2.0 mm were 0.930±0.024, 0.932±0.017 and 0.930±0.012 (F=0.24, P=0.788), and the PSNR values were 30.291±0.934, 30.351±1.002 and 30.271±1.143 (F=0.07, P=0.929). No significant differences were found in SSIM and PSNR values after artifact removal using CNN-MARS and U-net-MARS for different thicknesses of cobalt-chromium alloys (all P>0.05). Visualization demonstrated a high degree of similarity between the images before and after artifact removal using both MARSs. However, CNN-MARS displayed clearer metal edges and preserved more tissue details when compared with U-net-MARS. Conclusions: Both the CNN-MARS and U-net-MARS models developed in this study effectively remove the metal artifacts and enhance the image quality. CNN-MARS exhibited an advantage in restoring tissue structure information around the artifacts compared to U-net-MARS.

Constraints on Cosmic Strings Using Data from the Third Advanced LIGO-Virgo Observing Run

We search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 dataset. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks, and, for the first time, kink-kink collisions. A template-based search for short-duration transient signals does not yield a detection. We also use the stochastic gravitational-wave background energy density upper limits derived from the O3 data to constrain the cosmic string tension Gμ as a function of the number of kinks, or the number of cusps, for two cosmic string loop distribution models. Additionally, we develop and test a third model that interpolates between these two models. Our results improve upon the previous LIGO-Virgo constraints on Gμ by 1 to 2 orders of magnitude depending on the model that is tested. In particular, for the one-loop distribution model, we set the most competitive constraints to date: Gμ≲4×10^{-15}. In the case of cosmic strings formed at the end of inflation in the context of grand unified theories, these results challenge simple inflationary models.

Constraints on Cosmic Strings Using Data from the Third Advanced LIGO-Virgo Observing Run

We search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 dataset. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks, and, for the first time, kink-kink collisions. A template-based search for short-duration transient signals does not yield a detection. We also use the stochastic gravitational-wave background energy density upper limits derived from the O3 data to constrain the cosmic string tension Gμ as a function of the number of kinks, or the number of cusps, for two cosmic string loop distribution models. Additionally, we develop and test a third model that interpolates between these two models. Our results improve upon the previous LIGO-Virgo constraints on Gμ by 1 to 2 orders of magnitude depending on the model that is tested. In particular, for the one-loop distribution model, we set the most competitive constraints to date: Gμ≲4×10^{-15}. In the case of cosmic strings formed at the end of inflation in the context of grand unified theories, these results challenge simple inflationary models.

[The impact of ambient temperature exposure on emergency calls-a time series analysis based on data of Xuchang and Zhengzhou]

Objective: To investigate the effect of hourly ambient temperature exposure on emergency calls in Xuchang city and Zhengzhou city. Methods: The hourly meteorological data, air pollution data and emergency calls of Xuchang city and Zhengzhou city were collected from January 1, 2017 to October 31, 2019. A distributed lag non-linear model was used to calculate the excess relative risk (ERR). The lag effect and cumulative effect of extreme temperature exposure on emergency calls were evaluated. Results: The relationship between hourly temperature exposure and emergency calls was a U-shaped curve. In Xuchang city and Zhengzhou city, both low and high temperatures would increase the number of hourly emergency calls. The earliest effect of low temperature occurred at a lag of 22 h and 52 h, with ERR values (95%CI) about 0.20% (0.00%, 0.39%) and 0.11% (0.00%, 0.22%), respectively. The earliest effect of high temperature occurred at a lag of 0 h with ERR values about 1.59% (1.09%, 2.09%) and 1.45% (1.22%, 1.69%), respectively. High temperature had the greatest impact on the number of emergency calls of cardiovascular disease at a lag of 4-8 h. The cumulative ERR values (95%CI) of the two cities were 8.70% (4.98%, 12.75%) and 3.89% (2.61%, 5.22%), respectively. Conclusion: High temperature exposure could increase the number of emergency calls within a few hours, while the effect of low temperature would not occur until 22 hours later.

MiR-101 promotes nasopharyngeal carcinoma cell apoptosis through inhibiting Ras/Raf/MEK/ERK signaling pathway

The article "MiR-101 promotes nasopharyngeal carcinoma cell apoptosis through inhibiting Ras/Raf/MEK/ERK signaling pathway, by R.-S. Wu, E.-H. Qiu, J.-J. Zhu, J.-R. Wang, H.-L. Lin, published in Eur Rev Med Pharmacol Sci 2018; 22(1): 150-157-DOI: 10.26355/eurrev_201801_14112-PMID: 29364482" has been withdrawn from the authors. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/14112.

[Association between low handgrip strength and air pollution among people aged 50 years and over]

Objective: To examine the association between long-term exposure to ambient PM(2.5) combined with indoor air pollution and handgrip strength among people aged 50 and over. Methods: Data were from the first wave of World Health Organization Study on global AGEing and adult health in China. Ambient annual concentration of PM(2.5) was estimated by using the satellite data we also investigated the use of fuels and chimneys as indoor air pollution. A two-level (individual level and community level) linear model was applied to examine the association between long-term exposure to ambient PM(2.5) combined with indoor air pollution and the handgrip strength. Results: A total of 13 175 individuals aged 50 years and over were included for analysis. The handgrip strength was (26.67±0.54) kg. Ambient PM(2.5) was found to be significantly associated with the risk of decreased handgrip strength. Outdoor PM(2.5) concentration was negatively correlated with handgrip strength (β=-0.23, 95%CI: -0.31 - -0.14) decrease in handgrip strength after adjusting for gender, age, residence, education, household assets, intake of vegetables and fruits, smoking and drinking, physical activity. In rural area, compared to those who used solid fuel, use of clean fuel increased (β=1.41, 95%CI: 0.36-2.46) handgrip strength. But in urban area, we did not find any statistically significant association between the use of clean fuel and handgrip strength (β=0.19, 95%CI: -0.95-1.32). Conclusion: This study found that long-term exposure to ambient PM(2.5) combined with indoor air pollution was significantly associated with low handgrip strength among people aged 50 years and over, this suggested that ambient PM(2.5) might serve as one of the risk factors for low physical function seen in the people aged 50 years and over.

Silica-based colloid centrifugation enhances sperm quality in cockerel semen

1. Percoll^TM is one of the most widely used colloid for animal sperm preparation. The aim of this study was to evaluate whether Percoll^TM colloid centrifugation could be practical to improve cockerel sperm quality, and to compare the effects of Percoll^TM single layer centrifugation (SLC) and density gradient centrifugation (DGC) in order to obtain the most optimal protocol for cockerel semen.2. In the experiment with Percoll^TM SLC for fresh semen, an increase of motile sperm was seen after Percoll^TM 80% SLC and 90% SLC was conducted, at levels of 28.8% and 30.2% respectively (P < 0.01). The increase of progressively motile sperm after Percoll^TM 80% SLC and 90% SLC was 177.2% and 202.4% respectively (P < 0.01). Meanwhile, for semen stored at 4°C for 24 h, the increase of motile sperm after Percoll^TM 70% SLC and 80% SLC was 41.2% and 44.0% (P < 0.01), and the increase of progressive sperm after Percoll^TM 70% SLC and 80% SLC was 71.3% and 83.1% respectively (P < 0.01). Both the percentage of motile sperm and progressive sperm of the fresh and stored cockerel semen after appropriate Percoll^TM SLC was significantly enhanced.3. Sperm membrane integrity did not show any decrease after Percoll^TM centrifugation compared with non-centrifuged semen, which suggested that the Percoll^TM centrifugation treatment in this study did not cause damage to cockerel sperm membranes.4. In the experiment regarding the comparison of Percoll^TM SLC and DGC with fresh semen, the increase of motile sperm after Percoll^TM 80% SLC, 90% SLC and 40%/80% DGC was 29.5%, 36.4%, and 25.0% respectively; and the increase of progressive sperm was 44.7%, 58.5%, and 54.7%, respectively. For semen stored at 4°C for 24 h, the increase of motile sperm after Percoll^TM 70% SLC, 80% SLC and 35%/70% DGC were 41.2%, 44.0%, and 26.4%; and the increase of progressive sperm was 71.3%, 83.1%, and 43.7%, respectively. There were no significant differences between the increase of sperm motility after Percoll^TM 80%, 90% SLC or Percoll^TM 40%/80% DGC in fresh cockerel semen. There was no significant difference between Percoll^TM 70%, 80% SLC and Percoll^TM 35%/70% in stored cockerel semen. There was a tendency for sperm recovery rates with Percoll^TM SLC to be higher than Percoll^TM DGC, although this did not reach statistical significance in this study.5. It was concluded that Percoll^TM SLC was more suitable for cockerel sperm separation than Percoll^TM DGC. The results suggested that Percoll^TM 80% SLC was the most optimal procedure to separate fresh cockerel sperm and Percoll^TM 70% SLC was the most optimal procedure to separate stored cockerel sperm. Percoll^TM SLC is more simple, user-friendly and economical and less time-consuming than DGC for cockerel semen processing.

MiR-101 promotes nasopharyngeal carcinoma cell apoptosis through inhibiting Ras/Raf/MEK/ERK signaling pathway

OBJECTIVE

Extra-cellular signal regulated kinase (ERK)/mitogen activated protein kinase (MAPK) signaling pathway is widely involved in cell proliferation and apoptosis. MAPK kinase 1 (MEK1) is the upstream protein kinase of ERK that can activate ERK/MAPK signaling pathway. microRNA-101 (MiR-101) down-regulation is found to be associated with nasopharyngeal carcinoma (NPC) pathogenesis. Bioinformatics analysis shows the complementary targeted relationship between miR-101 and the 3'-UTR of MEK1 mRNA. This study explores the role of miR-101 in regulating MEK1 expression, ERK/MAPK signaling pathway activation, and NPC pathogenesis.

MATERIALS AND METHODS

Dual luciferase assay confirmed the targeted relationship between miR-101 and MEK1. MiR-101 and MEK1 expressions were compared in inflammatory nasopharynx tissue and NPC tissue. MiR-101, MEK1, phosphorylated ERK 1/2 (p-ERK1/2), survivin expressions in NP69, CNE-1, HONE1, and C666-2 cell lines were detected. NPC cell line C666-1 was cultured in vitro and divided into four groups, including miR-NC, miR-101, si-NC and si-MEK1. Cell apoptosis was determined by flow cytometry. Cell proliferation was evaluated by EdU staining.

RESULTS

MiR-101 targeted inhibited MEK1 expression. MiR-101 was significantly down-regulated, while MEK1 was significantly elevated in NPC tissue compared with inflammatory nasopharynx tissue. MiR-101 was markedly declined, whereas MEK1, p-ERK1/2, and survivin were apparently increased in CNE-1, HONE1, and C666-1 cells compared with NP69 cells. MiR-101 mimic and/or si-MEK1 transfection significantly reduced MEK1, p-ERK1/2, and survivin levels, attenuated cell proliferation, and enhanced cell apoptosis.

CONCLUSIONS

Down-regulation of miR-101 was related to NPC pathogenesis. MiR-101 elevation suppressed NPC cell proliferation and promoted apoptosis through targeted inhibiting MEK1 expression to alleviate ERK/MAPK signaling pathway and survivin expression.

Evaluation of cockerel spermatozoa viability and motility by a novel enzyme based cell viability assay

1. The results of spermatozoa assessment by the WST-8 (2-[2-methoxy-4-nitrophenyl]-3-[4-nitrophenyl]-5-[2,4-disulfophenyl]-2H-tetrazolium, monosodium salt) assay, flow cytometry (FC) or computer-assisted sperm analysis (CASA) were compared. 2. Different live/killed ratios of cockerel semen were serially diluted to 120, 60, and 30 × 10⁶ cells/ml, and each sample was analysed by (1) WST-8 assay at 0, 10, 20, 30, 40, 50, 60 min, (2) viability with FC, and (3) motility with CASA. 3. The WST-8 reduction rate was closely correlated with spermatozoa viability and motility. The optimal semen concentration for the WST-8 assay was 120 × 10⁶ cells/ml, and the standard curves for spermatozoa viability and motility predictions, respectively, were y_viability60 = 162.8x + 104.96 (R² = 0.9594) after 60 min of incubation and y_motility40 = 225.09x + 96.299 (R² = 0.8475) after 40 min of incubation. 4. It was concluded that the WST-8 assay is useful for the practical evaluation of cockerel spermatozoa viability and motility. Compared to FC and CASA, the WST-8 assay does not require expensive and complex instrumentation in the lab. Furthermore, one well of the WST-8 reaction can be used to predict spermatozoa viability and motility at the same time, which all lead it to be efficient and economical for semen quality assessment.

Epidemiology and molecular characterization of chicken anaemia virus from commercial and native chickens in Taiwan

Chicken infectious anaemia (CIA) is a disease with a highly economic impact in the poultry industry. The infected chickens are characterized by aplastic anaemia and extreme immunosuppression, followed by the increased susceptibility to secondary infectious pathogens and suboptimal immune responses for vaccination. Commercially available CIA vaccines are routinely used in the breeders in Taiwan to protect their progeny with maternal-derived antibodies. However, CIA cases still occur in the field and little is known about the genetic characteristics of Taiwanese chicken anaemia viruses (CAVs). In this study, CAV DNA was detected in 72 of 137 flocks collected during 2010-2015. Among the PCR-positive samples, the coding regions of 51 CAVs were sequenced. Phylogenetic analysis of the VP1 gene revealed that, although most of Taiwanese CAVs belonged to genotypes II and III, some isolates were clustered into a novel genotype (genotype IV). Moreover, a Taiwanese isolate in this novel genotype IV appeared to be derived from a recombination event between genotypes II and III viruses. Five Taiwanese CAV isolates were highly similar to the vaccine strains, 26P4 or Del-Ros. Taken together, these results indicate that the sequences of CAVs in Taiwan are variable, and inter-genotypic recombination had occurred between viruses of different genotypes. Moreover, vaccine-like strains might induce clinical signs of CIA in chickens. Our findings could be useful for understanding the evolution of CAVs and development of a better control strategy for CIA.

[Study on the difference of binocular accommodative response between atients with intermittent exotropia under different viewing condition]

Objective: To evaluate the accommodative response of patients with intermittent exotropia (IXT) objectively, and study the changes of accommodative response of intermittent exotropia patients when maintaining binocular fusion. Methods: The prospective cohort study was used in this study. Twenty-four patients diagnosed with basic intermittent exotropia who visited the eye hospital of Wenzhou Medical University during October 2016 through January 2017 together with 24 normal volunteers were included, the 48 participants aged from 10 to 27 years old. The participants were divided into the case group and the control group. There were 11 males and 13 females in the case group, and 7 males and 17 females in the control group. The Open-filed autorefractor WAM-5500 (Grand Seiko, Japan) was used to measure the accommodative response of each eye under binocular and monocular viewing conditions at 5 m and 40 cm respectively. During the measurement, patients wore full correction spectacles to achieve distant best-corrected visual acuity of both eyes. The accommodative responses of each eye under binocular and monocular viewing conditions at distance or near between fellow eyes and groups were compared. Results: Under near fixation (40cm) binocular viewing conditions, the accommodative response of the fixating eye (-1.915±0.301)D was different from the deviating eye -1.649(-2.020, -0.304)D in the case group (Z=-3.714, P<0.001). Under near fixation monocular viewing conditions, the accommodative response of the fixating eye (-1.653±0.271)D was also different from the deviating eye -1.565 (-2.031, -0.667)D in the case group (Z=-2.971, P=0.003). During binocular viewing, the asymmetric value of the accommodative response between both eyes of the case group was 0.389(0.102, 1.458)D which was more significant than the normal controls' 0.155(0.009, 0.573)D (Z=-3.505, P<0.001), but during monocular viewing, there was no significant difference between the groups (Z=-1.908, P=0.056). Under near viewing conditions, the variation value of the fixating eyes of the case group was -0.228(-0.796, 0.382)D, which was greater than the variation value -0.086(-0.606, 0.628)D of the right eye of the normal controls, such difference is of statistical significance (Z=-2.279, P=0.023). Under distance viewing conditions, there was no significant difference in the accommodative response between fixating eyes and deviating eyes in case group neither during monocular viewing nor binocular viewing (t=-1.525, -1.729, P>0.05). Besides, the asymmetric values of accommodative response between groups were not significantly different (Z=-1.433, P=0.152. Z=-0.938, P=0.348). Under distance viewing conditions, the changes in accommodative response of each eye during both monocular viewing and binocular viewing were not significantly different between case group and normal controls (Z=-0.041, P=0.967. Z=-1.433, P=0.152). Conclusions: The accommodative responses of the fixating eye and deviating eye of patients with intermittent exotropia were asymmetric under near fixation binocular viewing conditions, and the accommodative response of the deviating eye tends to decrease. Besides, the change of accommodative response of the patients with intermittent exotropia when maintaining binocular fusion is more significant than that of the normal controls. (Chin J Ophthalmol, 2018, 54: 55-61).

[Commuting mode specific exposure to PM(2.5) in urban area of Guangzhou]

Objective: To find the differences in PM(2.5) exposure level in the context of four commuting modes (by walk, bicycle, bus and subway) in Guangzhou. Methods: The PM(2.5) exposure assessment was carried out from January to December 2015 in Guangzhou. PM(2.5) was measured by using SidePak individual dust meter (AM510, TSI Inc. USA) with time interval of 1 minute. Our measurement was taken on Monday, Wednesday, Friday and Sunday in the second week of each month and the samples were collected in the morning (07:00-09:00), afternoon (11:00-13:00) and evening (17:00-19:00). Results: A total of 284 air samples during walking, 281 air samples during bicycle riding, 278 air samples in bus, and 280 air samples in subway were collected. The median PM(2.5) concentrations exposed during walking, during bicycle riding, in bus and in subway were 38.4, 38.6, 23.3 and 24.1 μg/m(3), respectively, which were positive correlated with exposure concentration in fixed surveillance sites. The exposure level was lowest in summer, and highest in winter. The median of one-way exposure level to PM(2.5) from high to low were as follows: 21.0 μg for bicycle riding, 20.1 μg for walking, 5.1 μg for taking bus and 2.6 μg for taking subway. The season and time specific one-way exposure levels to PM(2.5) of four commuting modes were consistent. Conclusions: The exposure level to PM(2.5) was obviously higher during walking and bicycle riding than that in bus and subway. The exposure level to PM(2.5) during walking was higher than that during bicycle riding, in bus and in subway.

[Lagged effects of diurnal temperature range on mortality in 66 cities in China: a time-series study]

Objective: To estimate the effect of daily diurnal temperature range (DTR) on mortality in different areas in China. Methods: A time series study using the data collected from 66 areas in China was conducted, and Meta-analysis was used to analyze the estimates of associations between DTR and daily mortality. Modifying effects of extremely low and high DTR-mortality relationship by season and socioeconomic status (SES) were also evaluated respectively. Cumulative excess risk (CER) was used as an index to evaluate the effects. Results: The information about 1 260 913 registered deaths were collected between 1 January 2006 and 31 December 2011, we found the relationship between extreme DTR and mortality was non-linear in all regions and the exposure-response curve was J-shaped. In central and south areas of China, the result indicated the obvious acute effect of extremely high DTR, and the mortality effect in central area (CER=5.1%, 95% CI: 2.4%-7.9%) was significant higher than that in south area (CER=4.5%, 95% CI: 1.7%-7.3%). Regarding to the modification of seasons, the cumulative mortality effect of DTR in cold season (CER=5.8%, 95%CI: 2.5%-9.2%) was higher than that in hot season (CER=3.1%, 95%CI: 1.1%-5.1%). Generally, deaths among the elderly (≥75 years) were associated more strongly with extremely high DTR. Conclusions: The mortality effects of extremely DTR in different areas and seasons showed different characteristics, that in central area and in cold season it was significantly stronger. After modified by season and SES, DTRs were the greatest threat to vulnerable population, especially to the elderly (≥75 years). Therefore, more attention should be paid to vulnerable groups and protection measures should be taken according to the local and seasonal conditions.

[Effectiveness of health education about heat wave hazard prevention in the elderly: a mixed effect model analysis]

Objective: To evaluate the effectiveness of health education about prevention of heat wave hazard in the elderly. Methods: A non-randomized controlled trial was conducted during the summer of 2015 among a sample of residents aged ≥60 years in Panyu district, Guangzhou. Eight intervention measures for heat wave hazard prevention were taken in intervention group for 3 months (from August to October) and in control group no intervention measures were taken. The comparison of intervention effects was conducted between the intervention group and control group with mixed effect model after the collection of related information with same questionnaire. Results: After adjusting of family per capita income, family air-condition availability, alcohol use, disease history and time, the average score of risk awareness in the intervention group increased by 1.62, while it was 0.51 in the control group, the difference was significant (t=2.76, P=0.006). A significant effect was observed in the intervention group on the reduction of hospitalizations due to chronic diseases. The hospitalization rate due to chronic diseases in resent 3 months in the intervention group decreased from 32.39% (46/142) before intervention to 28.87% (41/142) after intervention; while in the control group, it increased from 26.28% (41/156) before intervention to 36.53% (57/156) after intervention. There was no significant difference between the two groups in awareness of knowledge on heat wave hazard prevention and the score of adaptation to heat wave. Conclusion: Health education programs could improve the risk awareness on heat waves, and reduce the hospitalizations due to chronic diseases in the elderly.

Differential effects of grape juice on gastric emptying and renal function from cisplatin-induced acute adverse toxicity

Grape skin and seeds contain large amounts of phytochemicals such as polyphenols, resveratrol, and proanthocyanidins, which possess antioxidant activities. Cisplatin is widely used in the treatment of cancer. High doses of cisplatin have also been known to produce acute adverse effects. The aim of this study was to investigate the protective effects of antioxidant properties of whole grape juice (with skin and seeds) on cisplatin-induced acute gastrointestinal tract disorders and nephrotoxicity in Wistar rats. Gastric emptying is significantly increased in whole grape juice-pretreated rats when compared to cisplatin treatment alone. The expression of ghrelin mRNA of stomach is increased in rats with whole grape juice. However, pretreatment with whole grape juice did not reduce renal function markers in acute renal toxicity. No significant changes were recorded in the oxidative stress/antioxidant status parameters of any study group. In contrast, pretreatment with whole grape juice slightly improved tubular cell vacuolization, tubular dilatation, and cast formation in renal tubules. These results show that consumption of whole grape juice induces somewhat beneficial effects in preventing cisplatin-mediated dyspepsia but does not offer protection against cisplatin-induced acute renal toxicity.

Hes1 Increases the Invasion Ability of Colorectal Cancer Cells via the STAT3-MMP14 Pathway

The Notch pathway contributes to self-renewal of tumor-initiating cell and inhibition of normal colonic epithelial cell differentiation. Deregulated expression of Notch1 and Jagged1 is observed in colorectal cancer. Hairy/enhancer of split (HES) family, the most characterized targets of Notch, involved in the development of many cancers. In this study, we explored the role of Hes1 in the tumorigenesis of colorectal cancer. Knocking down Hes1 induced CRC cell senescence and decreased the invasion ability, whereas over-expression of Hes1 increased STAT3 phosphorylation activity and up-regulated MMP14 protein level. We further explored the expression of Hes1 in human colorectal cancer and found high Hes1 mRNA expression is associated with poor prognosis in CRC patients. These findings suggest that Hes1 regulates the invasion ability through the STAT3-MMP14 pathway in CRC cells and high Hes1 expression is a predictor of poor prognosis of CRC.

Folate intake and pancreatic cancer risk: an overall and dose-response meta-analysis

OBJECTIVE

Inconsistent findings of association between supplemental folate consumption and pancreatic cancer risk have been observed in the literature. This study aims to summarize the relationship between folate intake and risk of pancreatic cancer.

STUDY DESIGN

Pertinent studies published before November 2011 were identified by searching PubMed and Embase and by reviewing the reference lists of retrieved articles. The summary relative risks were estimated by the random effects model. A linear regression analysis of the natural logarithm of the relative risk (RR) was carried out to assess a possible dose-response relationship between folate intake and pancreatic cancer risk.

RESULTS

Ten studies on dietary and supplemental folate intake and pancreatic cancer (4 case-control and 6 cohort studies) were included in the meta-analysis. The pooled RRs of pancreatic cancer for the highest vs lowest categories of dietary folate intake and supplemental folate intake were 0.66 (95% CI: 0.49-0.88) and 1.08 (95% CI, 0.82-1.41), respectively. The dose-response meta-analysis indicated that a 100 μg/day increment in dietary folate intake conferred a RR of 0.93 (95% CI: 0.90-0.97). These findings support the hypothesis that dietary folate may play a protective role in carcinogenesis of pancreatic cancer.

Increased risks of parkinsonism in the 3 years after chronic renal failure

AIMS

Movement disorders are one of the central nervous system complications in uremic patients. Asterixis, multifocal myoclonus, and restless leg syndrome are well-documented in this category. Acute parkinsonism, however, is only reported in rare series with a small number of cases. In this study, we investigated the risk for parkinsonism during a 3-year follow-up period after a diagnosis of uremia.

METHODS

The Longitudinal Health Insurance Database in Taiwan was utilised. We identified a total of 2862 patients who had visited ambulatory care centers with a diagnosis of chronic renal failure between 1999 and 2001 as the study cohort. We further randomly selected 14,310 enrollees matched with the study cohort in terms of gender, age, and year of their index visit for comparison. Each patient was individually tracked for 3 years to identify the occurrence of parkinsonism. Stratified Cox proportional hazard regressions (stratified by age and gender) were performed for analyses.

RESULTS

We found the annual incidence rates of parkinsonism to be 1.2% and 0.6% in the uremic and non-uremic groups, respectively. Furthermore, uremic patients were more vulnerable to developing parkinsonism with a 1.81-fold higher risk [95%CI = (1.21-2.71)] than the non-uremic group after adjusting for diabetes mellitus, which did not augment the risk.

CONCLUSIONS

The importance of raising awareness regarding the early symptoms of parkinsonism among patients with uremia is tied to its early identification, with timely aggressive dialysis being able to apply to slow the progression of the disease and its symptoms. Further study is warranted to elucidate the pathophysiology of uremic parkinsonism.

Generation of transgenic chicks using an oviduct-specific expression system

We successfully replaced the ovalbumin gene of a magnum region in chickens with a human plasminogen activator. We constructed pL-eGFP, pL-tPAGFP and pL-2.8OVtPAGFP vectors and cultured 293FT chicken embryo fibroblasts, chicken primordial germ cells, Hela C127 cells, and oviduct epithelial cells. All vectors were expressed in the transfected cells, except pL-2.8OVtPAGFP vector, which was only expressed in oviduct epithelial cells. A lentivirus with pL-2.8OVtPAGFP was injected in fertilized eggs; 11 chicks hatched in the G₀ generation, four of them carried the tPAGFP. Two cockerels from the G₀ generation were crossed with four wild-type hens. Three chicks in G₁ carried the tPAGFP. We concluded that by using an oviduct-specific vector for transfection, human recombinant plasminogen activator protein can be expressed in the oviducts of laying hens. This character is inherited and can be reproduced with a need for repeated transfection.

A new hospice consulting system for terminal cancer patients in transferring to post-acute care options in Taiwan

The terminal cancer patients increase needs for hospice care day by day. A new hospice consulting system has been developed in Taiwan to provide options for terminal cancer patients in choosing a suitable post-acute hospice care while a combined hospice care system is also given by the consulting team in the acute wards. Hereinafter is our report. From March 2005 to January 2006, 313 terminal cancer patients were analysed. These patients had signed consent forms for palliative treatment and had received consultations from the new hospice consulting system. Multivariate analysis showed that the home care patients had better performance status (P = 0.012), less shortness of breath (P = 0.006), less limbs swelling (P = 0.043), less flatulency (P = 0.000) and less constipation (P = 0.018). Among the 162 patients with regular follow-up, the symptoms/signs were significantly improved after intervention of consulting team in pain (P = 0.000), shortness of breath (P = 0.000), difficulty in sleeping (P = 0.002), nausea (P = 0.004), constipation (P = 0.008), changes in skin (P = 0.024) and adoption (P = 0.000). This new system had significant improvement in the terminal cancer patients' symptoms/signs control in acute wards and could contribute to the care quality of home care patients.

Does multiple sclerosis increase risk of adverse pregnancy outcomes? A population-based study

Objective

To determine whether maternal multiple sclerosis (MS) is associated with increased risk of adverse pregnancy outcomes in an East Asian country by using a nationwide population-based dataset.

Method

This study linked two nationwide population-based datasets, the birth certificate registry and the Taiwan National Health Insurance Research Dataset. We identified a total of 174 women who gave birth from 2001 to 2003, who were diagnosed with MS within the 2 years preceding the index deliveries, together with 1,392 matched women without chronic disease as a comparison cohort. Multivariate logistic regression analyses were performed for estimation.

Results

We found that compared with healthy mothers, MS was independently associated with a 2.25-fold risk of preterm birth (95% CI = 1.37–3.70) and a 1.89-fold (95% CI = 1.30–2.76) higher risk of babies small for gestational age, after adjusting for family income and maternal, paternal, and infant characteristics. Mothers with MS were also more likely to have cesarean deliveries.

Conclusion

Our study documents increased the risk of adverse pregnancy outcomes for mothers with MS, highlighting a need for more intensive monitoring and obstetric care during pregnancy. Future studies should explore the distinct manifestations and mechanisms of MS in diverse ethnic groups, so more complete information can be provided to affected women concerning pregnancy.

Characterization of interleukin 8 in woodchucks with chronic hepatitis B and hepatocellular carcinoma

The eastern woodchuck, Marmota monax, represents a useful animal model to study hepatitis B virus infection in humans. However, immunological studies in this model have been impeded by a lack of basic information about the components of the immune system such as cytokines and chemokines. To clarify the role(s) of interleukin 8 (IL-8) in chronic hepatitis B and hepatocellular carcinoma (HCC) in the woodchuck model, we cloned and characterized the woodchuck IL-8 cDNA and genomic DNA. Sequence analysis revealed that the organization of the wk-IL-8 gene is similar to that of the human IL-8 gene and consists of four exons and three introns. Woodchuck IL-8 protein exhibits the conserved ELRCXC motif of IL-8 and shows 87, 82, 82 and 79% similarity with rabbit, ovine, bovine and human IL-8 proteins, respectively. The biological activity of wk-IL-8 was demonstrated using neutrophil chemotaxis assays. Wk-IL-8 could be readily detected in both tumor and non-tumor tissues with higher expression in the non-tumor tissues in most cases. The results from this study will facilitate the investigation of IL-8 in the immunopathogenesis of hepadnavirus-related diseases by the woodchuck model.

Biological treatment of thin-film transistor liquid crystal display (TFT-LCD) wastewater

The amount of pollutants produced during manufacturing processes of TFT-LCD (thin-film transistor liquid crystal display) substantially increases due to an increasing production of the opto-electronic industry in Taiwan. The total amount of wastewater from TFT-LCD manufacturing plants is expected to exceed 200,000 CMD in the near future. Typically, organic solvents used in TFT-LCD manufacturing processes account for more than 33% of the total TFT-LCD wastewater. The main components of these organic solvents are composed of the stripper (dimethyl sulphoxide (DMSO) and monoethanolamine (MEA)), developer (tetra-methyl ammonium hydroxide (TMAH)) and chelating agents. These compounds are recognized as non-or slow-biodegradable organic compounds and little information is available regarding their biological treatability. In this study, the performance of an A/O SBR (anoxic/oxic sequencing batch reactor) treating synthetic TFT-LCD wastewater was evaluated. The long-term experimental results indicated that the A/O SBR was able to achieve stable and satisfactory removal performance for DMSO, MEA and TMAH at influent concentrations of 430, 800, and 190 mg/L, respectively. The removal efficiencies for all three compounds examined were more than 99%. In addition, batch tests were conducted to study the degradation kinetics of DMSO, MEA, and TMAH under aerobic, anoxic, and anaerobic conditions, respectively. The organic substrate of batch tests conducted included 400 mg/L of DMSO, 250 mg/L of MEA, and 120 mg/L of TMAH. For DMSO, specific DMSO degradation rates under aerobic and anoxic conditions were both lower than 4 mg DMSO/g VSS-hr. Under anaerobic conditions, the specific DMSO degradation rate was estimated to be 14 mg DMSO/g VSS-hr, which was much higher than those obtained under aerobic and anoxic conditions. The optimum specific MEA and TMAH degradation rates were obtained under aerobic conditions with values of 26.5 mg MEA/g VSS-hr and 17.3 mg TMAH/g VSS-hr, respectively. Compared to aerobic conditions, anaerobic biodegradation of MEA and TMAH was much less significant with values of 5.6 mg MEA/g VSS-hr and 0 mg TMAH/g VSS-hr, respectively. In summary, biological treatment of TFT-LCD wastewater containing DMSO, MEA, and TMAH is feasible, but appropriate conditions for optimum biodegradation of DMSO, MEA, and TMAH are crucial and require carefully operational consideration.

UCP2 A55V variant is associated with obesity and related phenotypes in an aboriginal community in Taiwan

OBJECTIVE

Human uncoupling proteins 2 and 3 (UCP2 and UCP3) are two mitochondrial proteins that are involved in the control of metabolism of fatty acid and possibly protect against oxidative damage. The aim of this study was to analyze genetic associations of four polymorphisms of the UCP2 and UCP3 genes with insulin, leptin concentration and obesity in Taiwan aborigines.

RESEARCH METHODS

Four polymorphisms were compared in 324 obese (body mass index (BMI) > or =30 kg/m(2)) and overweight (30>BMI > or =25 kg/m(2)) subjects, and 114 normal weight subjects (BMI <25 kg/m(2)) in an aboriginal community of southern Taiwan. Anthropometric characteristics and fasting levels of insulin, leptin, triglycerides and cholesterol were measured.

RESULTS

Before and after adjusting for age distribution, only the Val55 allele in exon 4 of the UCP2 gene increased the risk of overweight and obesity (adjusted odds ratio (OR)=2.02, P=0.004) in comparison with Ala55. UCP2 V55V is also associated with higher fasting insulin levels than A55V (P=0.01) and A55A (P=0.04) in the obese/overweight group. Using the COCAPHASE program of the UNPHASED software, haplotype analysis of three single nucleotide polymorphisms (A55V-G866A-C-55T) revealed that A-G-C (73% in obese subjects and 77% in controls) was the most common haplotype and that the haplotype V-A-T (13% in obese subjects and 5% in controls) was significantly increased in obese and overweight subjects (BMI > or =25 kg/m(2)) (OR=2.62, P<0.001).

DISCUSSIONS

UCP2 A55V variant might predispose to obesity and Val55 allele to confer population-attributable risk for 9.5% of obese disorders and increase insulin concentrations. The V-A-T haplotype within UCP2-UCP3 gene cluster is also significantly associated with obesity in Paiwan aborigines.

Bayesian random-effect model for predicting outcome fraught with heterogeneity--an illustration with episodes of 44 patients with intractable epilepsy

OBJECTIVE

The study aimed to develop a predictive model to deal with data fraught with heterogeneity that cannot be explained by sampling variation or measured covariates.

METHODS

The random-effect Poisson regression model was first proposed to deal with over-dispersion for data fraught with heterogeneity after making allowance for measured covariates. Bayesian acyclic graphic model in conjunction with Markov Chain Monte Carlo (MCMC) technique was then applied to estimate the parameters of both relevant covariates and random effect. Predictive distribution was then generated to compare the predicted with the observed for the Bayesian model with and without random effect. Data from repeated measurement of episodes among 44 patients with intractable epilepsy were used as an illustration.

RESULTS

The application of Poisson regression without taking heterogeneity into account to epilepsy data yielded a large value of heterogeneity (heterogeneity factor = 17.90, deviance = 1485, degree of freedom (df) = 83). After taking the random effect into account, the value of heterogeneity factor was greatly reduced (heterogeneity factor = 0.52, deviance = 42.5, df = 81). The Pearson chi2 for the comparison between the expected seizure frequencies and the observed ones at two and three months of the model with and without random effect were 34.27 (p = 1.00) and 1799.90 (p < 0.0001), respectively.

CONCLUSION

The Bayesian acyclic model using the MCMC method was demonstrated to have great potential for disease prediction while data show over-dispersion attributed either to correlated property or to subject-to-subject variability.

Cyclosporine C2 monitoring is superior to C0 in predicting acute cellular rejection in heart transplant recipients in Taiwan

The cyclosporine (CsA) blood concentration at 2 hours postdose (C2) has been shown to be better than trough level (C0) to predict acute cellular rejection (ACR) in solid organ transplantations. We tried to assess the superiority of C2 monitoring to C0 in heart transplantation (HTx). Prospective data were collected from the HTx recipients from November 1991 to April 2003. The 100 patients surviving longer than 3 months after HTx, provided 237 sample sets, with ACR graded by endomyocardial biopsy (EMB) and concurrent C0 and C2 levels. ACR was defined as International Society of Heart and Lung Transplantation (ISHLT) grade lb or higher. Nonparametric methods, logistic regression model, and receiver operating characteristic (ROC) analysis were used. There was no significant demographic heterogeneity between ACR and non-ACR groups. C2 was significantly lower in ACR than non-ACR groups (P = .0192) whereas C0 showed no significant difference. In the logistic regression model, C2 was a significant predictor against ACR (P = .026, odds ratio = 0.76 per 100 ng/mL), but C0 was not. ROC analysis showed that C2 of 600 ng/mL might provide the optimal cut-off point, with a sensitivity of 51.23% and a specificity of 71.43%, but C0 did not show this association. In conclusion, C2 monitoring is superior to C0 for predicting ACR in HTx. ACR should be suspected when the C2 value is below 600 ng/mL.

Chemoprevention of gastric cancer by celecoxib in rats

BACKGROUND

Overexpression of cyclooxygenase 2 (COX-2) is frequently detected in gastric cancer and is believed to play a crucial role in gastric carcinogenesis.

AIM

We examined the chemopreventive effect of a COX-2 inhibitor in an animal model of stomach carcinogenesis.

METHODS

Eighty six male Wistar rats were divided into six different treatment groups: group A, water alone (n = 5); group B, N-methyl-N'-nitro-N-nitrosoguanidine (MNNG 100 micro g/ml) (n = 16); group C, indomethacin (3 mg/kg/day) (n = 16); group D, celecoxib (5 mg/kg/day) (n = 17); group E, celecoxib (10 mg/kg/day) (n = 16); and group F, celecoxib (20 mg/kg/day) (n = 16). Group B-F animals were treated with 10% sodium chloride (in the initial six weeks) and MNNG in drinking water to induce adenocarcinoma in the stomach. All animals received treatment for 40 weeks, and were sacrificed after death or at 48 weeks. Gastric neoplasm was evaluated by histology.

RESULTS

The incidences of gastric cancer were 0% in group A, 75% in group B, 68.8% in group C, 70.6% in group D, 18.8% in group E, and 31.3% in group F (p = 0.002, ANOVA). Compared with MNNG controls, treatment with celecoxib 10 mg/kg/day also showed lower tumour multiplicity (0.19 (0.40) v 1.00 (0.73); p = 0.004) and lower mean tumour volume (2.4 v 2805 mm(3); p = 0.02). Although tumours had significantly higher COX-2 expression than their adjacent normal tissues (p<0.02), there was no significant difference in COX-2 levels among tumours in the different treatment groups. The lowest tumour prostaglandin E(2) level was found in the indomethacin treated group, suggesting that the chemopreventive effect of celecoxib may be mediated by a COX independent pathway.

CONCLUSION

While treatment with indomethacin had no significant effect on tumour development, treatment with celecoxib reduced gastric cancer incidence and growth in rats.

Reversal of Taxol resistance in hepatoma by cyclosporin A: involvement of the PI-3 kinase-AKT 1 pathway

Hepatoma cells are known to be highly resistant to chemotherapy. Previously, we have found differential Taxol resistance in human and murine hepatoma cells. The aim of this study was to examine the effect of a multidrug resistance inhibitor, cyclosporin A in combination with Taxol on hepatoma in vitro and in vivo, and to identify the possible mechanism involved in Taxol resistance. Simultaneous treatment of cyclosporin A (0-10 microM) and Taxol (0.1 microM) inhibited cell growth in vitro. Cyclosporin A interfered with Taxol (0.1 microM)-induced AKT activation and BAD phosphorylation. Cyclosporin A combined with Taxol treatment augments caspase-9, -3 activation and loss of mitochondrial membrane potential in HepG2 cells. PI3 kinase inhibitor, wortmannin, or a dominant-negative AKT1 expression vector treatment partially enhanced Taxol-induced apoptosis indicating that PI3 kinase-AKT pathway was involved in Taxol-resistance pathway. Moreover, combination treatment reduced tumour growth in SCID and C57BL/6 mice as compared to either Taxol or cyclosporin A treatment. Our results indicate that the combination of cyclosporin A and Taxol is effective in the reversal of Taxol resistance through the inhibition of PI3 kinase-AKT1 pathway.

Estrogen therapy for hepatectomy patients with poor liver function?

Estrogen is well known to promote liver regeneration after partial hepatectomy. Administration of estradiol prior to partial hepatectomy also induces increased activity of DNA synthesis. Endogenous aromatase plays a key role in the conversion of testosterone to estradiol. The aromatase activity was induced by IL-6, which is a key factor for liver regeneration. It has been reported that IL-6 interacts with gp80/130 receptor and regulates the STAT1/3 pathway to induce DNA synthesis in hepatocyte. The IL-6 induced aromatase activity results in increased serum estradiol level. This corresponded well with observation that estradiol was elevated after partial hepatectomy. Therefore, it is very likely that estradiol and IL-6 synergize in stimulation of hepatocyte proliferation during liver regeneration. We propose that a short-term estradiol treatment may be beneficial for patients with poor liver function after hepatectomy.

Molecular cloning and expression of woodchuck granulocyte-macrophage colony stimulating factor

Granulocyte-macrophage colony stimulating factor (GM-CSF) has immunoregulatory and antiviral effects, and may thus be promising for the treatment of chronic hepatitis B. Using woodchuck hepatitis virus (WHV)-infected woodchuck as an animal model to test the efficacy and safety of GM-CSF on the therapy of chronic hepatitis B, woodchuck GM-CSF will be required due to the apparent species-specific activity of GM-CSF. The cDNA of woodchuck GM-CSF was cloned using reverse transcription-polymerase chain reaction (RT-PCR) with primers deriving from highly conserved regions of GM-CSF genes from other species. The deduced amino acids, including the signal peptide, is 138 in length and its identities to human, murine, canine and bovine GM-CSFs are 63, 49, 63, and 63% respectively. The genomic DNA of woodchuck GM-CSF was also cloned by PCR. Its organization is highly homologous to that of human and murine GM-CSF genes, consisting of four exons and three introns. Cloned woodchuck GM-CSF was expressed transiently in 293T cells. The recombinant protein expressed was found to stimulate the growth and differentiation of woodchuck bone marrow cells, indicating the protein expressed by the cloned gene is functional. These results pave the way for future studies on the potential role of GM-CSF for the treatment of chronic hepatitis B by using this animal model.

Diagnosis of congenital hypothyroidism from human anagen scalp hair by infrared microspectroscopy

A highly efficient Fourier transform infrared (FT-IR) microscopy was used to determine the biophysical structure of anagen scalp hair roots of neonates suffering from congenital hypothyroidism (CH) due to ectopic thyroid. The present results indicate that the lower composition near 1,053 cm(-1) (also assigned to the aromatic iodide stretching band) in the infrared (IR) spectra of the hair roots for CH patients was directly associated with the lower serum level of T4 and fT4, and the elevated TSH levels determined by RIA method. This strongly implies the lower evidence of the aromatic iodide stretching band in the IR spectra of hair roots. These findings suggest that FT-IR microscopy has the potential to become a good diagnostic tool and that hair can be useful as a genetic marker.

2-Methoxyestradiol-induced caspase-3 activation and apoptosis occurs through G(2)/M arrest dependent and independent pathways in gastric carcinoma cells

BACKGROUND

2-Methoxyestradiol (2-Me), one of the estrogen metabolites, has recently been found to possess anti-angiogenesis activity in vivo. Many chemotherapeutic agents, such as taxol, docetaxel, and vinblastine, interact with microtubules and then induce apoptosis. It has been suggested that 2-Me acts on microtubules and results in G(2)/M-cycle arrest of tumor cells. Whether 2-Me induces apoptosis in gastric carcinoma cell lines is not known. Moreover, reactive oxygen species (ROS) produced by 2-Me may be involved in cytotoxicity of tumor cells. Thus, another objective of this study was to evaluate the relation between cell cycle arrest, ROS formation, and caspase activity levels after 2-Me treatment in gastric carcinoma cells.

METHODS

It was determined whether 2-Me directly induced apoptosis in two gastric carcinoma cell lines (SC-M1 and NUGC-3) through caspase-3 and caspase-8 activation and, eventually, induced DNA fragmentation. To clarify the effect of 2-Me-induced G(2)/M arrest in apoptosis, calcium ionophore, A23187, and thapsigargin were used to modulate 2-Me-induced cell cycle responses. Moreover, the role of 2-Me-induced ROS formation in the cell cycle responses also was evaluated.

RESULTS

It was found that 2-Me treatment resulted in G(2)/M-cycle arrest, caspase-8 and caspase-3 activation, and DNA fragmentation. In addition, the 2-Me induced, concomitant increases of peroxide and superoxide anions were correlated with G(2)/M-cycle arrest. Treatment with calcium ionophore A23187 and thapsigargin partially reversed the 2-Me-induced G(2)/M-cycle arrest, with a concomitant decrease in both peroxide and superoxide levels. Moreover, A23187 blocked the 2-Me-induced caspase-3 activation, whereas thapsigargin had no effect. Treatment with calcium channel blockers did not affect 2-Me-induced cell cycle arrest or caspase-3 activation.

CONCLUSIONS

These results suggest that the 2-Me-induced apoptosis of gastric carcinoma cells by DNA fragmentation accompanied caspase activation. Elevation of free radicals was associated with G(2)/M-cycle arrest. The induction of G(2)/M-cycle arrest is not a prerequisite for caspase activation.

2-Methoxyestradiol-induced caspase-3 activation and apoptosis occurs through G(2)/M arrest dependent and independent pathways in gastric carcinoma cells

BACKGROUND

2-Methoxyestradiol (2-Me), one of the estrogen metabolites, has recently been found to possess anti-angiogenesis activity in vivo. Many chemotherapeutic agents, such as taxol, docetaxel, and vinblastine, interact with microtubules and then induce apoptosis. It has been suggested that 2-Me acts on microtubules and results in G(2)/M-cycle arrest of tumor cells. Whether 2-Me induces apoptosis in gastric carcinoma cell lines is not known. Moreover, reactive oxygen species (ROS) produced by 2-Me may be involved in cytotoxicity of tumor cells. Thus, another objective of this study was to evaluate the relation between cell cycle arrest, ROS formation, and caspase activity levels after 2-Me treatment in gastric carcinoma cells.

METHODS

It was determined whether 2-Me directly induced apoptosis in two gastric carcinoma cell lines (SC-M1 and NUGC-3) through caspase-3 and caspase-8 activation and, eventually, induced DNA fragmentation. To clarify the effect of 2-Me-induced G(2)/M arrest in apoptosis, calcium ionophore, A23187, and thapsigargin were used to modulate 2-Me-induced cell cycle responses. Moreover, the role of 2-Me-induced ROS formation in the cell cycle responses also was evaluated.

RESULTS

It was found that 2-Me treatment resulted in G(2)/M-cycle arrest, caspase-8 and caspase-3 activation, and DNA fragmentation. In addition, the 2-Me induced, concomitant increases of peroxide and superoxide anions were correlated with G(2)/M-cycle arrest. Treatment with calcium ionophore A23187 and thapsigargin partially reversed the 2-Me-induced G(2)/M-cycle arrest, with a concomitant decrease in both peroxide and superoxide levels. Moreover, A23187 blocked the 2-Me-induced caspase-3 activation, whereas thapsigargin had no effect. Treatment with calcium channel blockers did not affect 2-Me-induced cell cycle arrest or caspase-3 activation.

CONCLUSIONS

These results suggest that the 2-Me-induced apoptosis of gastric carcinoma cells by DNA fragmentation accompanied caspase activation. Elevation of free radicals was associated with G(2)/M-cycle arrest. The induction of G(2)/M-cycle arrest is not a prerequisite for caspase activation.

Folate depletion and elevated plasma homocysteine promote oxidative stress in rat livers

This study was designed to determine whether nutritional folate depletion exerts hepatic oxidative stress in relation to elevated plasma homocysteine. To mimic various extents of folate depletion status in vivo, male Wistar rats were fed an amino acid-defined diet containing either 8 (control), 2, 0.5, or 0 mg folic acid/kg diet. After a 4-wk feeding period, the plasma and hepatic folate concentrations of the rats decreased significantly with each decrement of dietary folate. Folate depletion did not significantly affect two major liver antioxidants: reduced glutathione and alpha-tocopherol. Conversely, folate depletion decreased Cu-Zn superoxide dismutase and glutathione peroxidase activities, but had no effect on catalase activity in liver homogenates. Lipid peroxidation products, as measured by thiobarbituric acid-reactive substances, were significantly higher in livers of folate-depleted rats than in those of the controls. This occurrence of hepatic oxidative stress in folate-depleted rats was confirmed by demonstrating an increased susceptibility of livers of folate-depleted rats to lipid peroxidation induced by additional H2O2 or Fe(2+) treatments compared with the controls. Decreasing dietary folate intake resulted in graded increases in plasma homocysteine concentrations of folate-depleted rats. Elevated plasma homocysteine and decreased plasma and hepatic folate concentrations in folate-depleted rats were all strongly and significantly correlated with increased liver lipid peroxidation (/r/ > or = 0.58, P < 0.0003). These data demonstrate that folate depletion and elevated plasma homocysteine promote oxidative stress in rat livers.

Differentiation of hair growth cycle from scalp hair roots for the diagnosis of glucose-6-phosphate dehydrogenase deficiency in neonates

Hair analysis can be used as a screening tool in the diagnosis of genetic diseases. The scalp hair roots of 67 normal neonates and 39 neonates with glucose-6-phosphate dehydrogenase (G6PD) deficiency were analysed using Fourier transform infrared (FT-IR) microspectroscopy to differentiate the stages of the hair growth cycle and to diagnose the genetic disorder on the basis of spectral differences. We have demonstrated that FT-IR microspectroscopy is a rapid and effective noninvasive diagnostic method to differentiate scalp hair roots of normal neonates into the anagen, catagen or telogen phases of the hair growth cycle, using IR spectral differences within the 3000-2800 cm(-1) region and the IR peak area ratio of 2854 cm(-1)/2873 cm(-1) or 1084 cm(-1)/amide II band (p<0.001). Moreover, G6PD-deficient neonates could be accurately diagnosed from telogen phase hair roots owing to significant differences in IR peak area ratios of 2854 cm(-1)/2873(-1) or 1084 cm(-1)/amide II band compared to normal values in healthy neonates. The result suggests that the application of FT-IR microspectroscopy may be capable not only of differentiating the hair growth cycle into anagen, categen or telogen phases but also of detecting G6PD deficiency. Hair root analysis promises to be a useful complement to serum and urine analysis in the diagnosis of genetic diseases.

Effect of skin-penetrating enhancers on the thermophysical properties of cholesteryl oleyl carbonate embedded in a thermo-responsive membrane

The effect of skin-penetrating enhancers such as propylene glycol (PG), Azone and ethanol on the thermophysical properties of cholesteryl oleyl carbonate (COC) was investigated using differential scanning colorimetry (DSC) and microscopic Fourier-transform infrared (FT-IR) spectroscopy. The results indicate that PG did not influence the DSC thermograms and IR spectra of COC in the different ratios of COC and PG mixture; whereas Azone interacted with COC not only to lower the semectic-cholesteric phase transition temperature of COC but also to induce a new IR spectral peak at 1653 cm(-1) which shifted from the carbonyl stretching band (1636 cm(-1)) of Azone. Ethanol did not interact with COC, but it influenced the IR spectral peak intensity of COC at 1253 cm(-1). The peak intensity at 1253 cm(-1) gradually rose with the time of ethanol evaporation and was similar to that of the temperature effect. The solubility parameter was also used to explain the miscibility and interaction between COC and PG, Azone or ethanol.

Male predominance in hepatocellular carcinoma: new insight and a possible therapeutic alternative

Hepatocellular carcinoma is one of the most common cancers in the world. The male to female ratio is 3-6 to 1 in patients with hepatocellular carcinoma. Although steroid hormones and receptors have been examined extensively for their role in the growth regulation of hepatocellular carcinoma, the direct stimulation of hepatocellular carcinoma by steroid hormones still awaits elucidation. On the other hand, clinical trials using antagonists for steroid hormones to treat hepatocellular carcinoma were found to be mostly ineffective. Recently it has been found that 2-methoxyestradiol - an estrogen metabolite - is effective in growth inhibition of various tumor cells as well as in angiogenesis inhibition. Since estrogen is metabolized in the liver, it is conceivable that females with menstruation cycles have more estrogen metabolized in their liver, consequently more 2-methoxyestradiol produced which could inhibit tumor growth in situ. We propose that the low incidence and mortality of hepatocellular carcinoma found in females may have resulted from the high levels of 2-methoxyestradiol produced in the liver during their reproductive years. Consequently, the growth of hepatocellular carcinoma in females is delayed significantly as compared to males. The potential of using 2-methoxyestradiol for treatment of patients with hepatocellular carcinoma after resection of tumor should be explored.

Comparison of 2-methoxyestradiol-induced, docetaxel-induced, and paclitaxel-induced apoptosis in hepatoma cells and its correlation with reactive oxygen species

BACKGROUND

Previously, the authors observed that paclitaxel treatment of hepatoma cells resulted in differential cytotoxicity. Whether other antimicrotubule agents (docetaxel and 2-methoxyestradiol) are more effective than paclitaxel is not clear. Moreover, whether the modulation of reactive oxygen species (ROS) is involved in the drug-induced growth inhibition of hepatoma cells is not known.

METHODS

The authors examined the effects of 2-methoxyestradiol, paclitaxel, and docetaxel on HepG2, Hep3B, HA22T/VGH, and Hepa1-6 hepatoma cell lines. The parameters examined included cell viability, cell membrane permeability, cell cycle distribution, DNA fragmentation, and ROS generation.

RESULTS

Docetaxel and paclitaxel inhibited the growth of hepatoma cells at submicromolar concentrations, whereas that of 2-methoxyestradiol was within a micromolar range. This drug-induced growth inhibition was cell cycle dependent. 2-Methoxyestradiol-treated (10-50 microM) cells resulted in G2/M block prior to apoptosis. High dose (0.1 microM) docetaxel- and paclitaxel-treated cells resulted in a G2/M arrest followed by generation of polyploidy or apoptosis; however, low dose (0.01 microM) treatment induced apoptosis without G2/M arrest. The low dose effect was more significant in docetaxel-treated cells than in paclitaxel-treated cells. Although these antimicrotubule agents increased the formation of ROS, antioxidant treatment did not block drug-induced cell cycle and growth inhibition effects.

CONCLUSIONS

The current results suggest that the growth inhibition of hepatoma cells induced by 2-methoxyestradiol, paclitaxel, and docetaxel was mediated through G2/M-phase arrest, caspase activation, and DNA fragmentation. The drug-induced apoptosis was independent of ROS formation. Docetaxel was more effective than paclitaxel in killing hepatoma cells. The potential of using 2-methoxyestradiol and docetaxel for the treatment of patients with hepatoma is worthy of further study.

Combination of angiogenesis inhibitor TNP-470 with cytotoxic drugs in experimental therapy of nasopharyngeal carcinoma

This study was conducted to evaluate the effectiveness of angiogenesis inhibitor 6-O-(N-chloroacetyl-carbamoyl)-fumagillol (TNP-470. AGM-1470) in the treatment of nasopharyngeal carcinoma (NPC) alone and in combination with cytotoxic agents. Forty-two male BALB/c nude mice bearing human NPC cell line CNE-2 were randomized into 6 groups: those treated with saline solution, TNP-470, cisplatin (DDP), fluorouracil (5-FU), TNP-470 + DDP, and TNP-470 + 5-FU, respectively. In every treatment group, tumor growth was suppressed significantly. The combination of 5-FU with TNP-470 showed significant enhancement in antitumor efficacy. TNP-470 also enhanced the inhibitory effect of DDP, although not to statistical significance. All animals gained in body weight, although treatment with 5-FU caused slight, reversible diarrhea of 2 to 3 days' duration. The results showed that TNP-470 suppressed the growth of the human NPC cell line and enhanced the antitumor effect of 5-FU without increasing its toxicity. The combination of angiogenesis inhibitors with conventional cytotoxic agents is promising in the treatment of NPC.

Effects of ICAM-1 antisense oligonucleotide on the tubulointerstitium in mice with unilateral ureteral obstruction

Effects of ICAM-1 antisense oligonucleotide on the renal tubulointerstitium in mice with unilateral ureteral obstruction.

BACKGROUND

To extend our previous study of the therapy of the renal lesions of unilateral ureteral obstruction (UUO) in mice by an inhibitor of intercellular adhesion molecule-1 (ICAM-1), we investigated the blocking effects of ICAM-1 antisense oligonucleotides (ASONs) on the ICAM-1 expression in mouse kidney.

METHODS

First, ICAM-1 ASON was transducted into mouse renal tubular epithelial cells to investigate the effects of ICAM-1 ASON in vitro. Second, fluorescein isothiocyanate (FITC)-labeled ICAM-1 ASON was injected intravenously to determine the distribution of the ASON in vivo. Third, the expression of ICAM-1 in kidney and the changes of renal morphology were observed to investigate the therapeutic effects of ICAM-1 ASON on the UUO mice in vivo.

RESULTS

The expressions of ICAM-1 in the epithelial cells induced by interleukin-1beta were inhibited by ICAM-1 ASON at the dosages of 100 and 200 nmol/L. Twenty-four hours after an introvenous injection with FITC-labeled ICAM-1 ASON, the highest level of fluorescein was detected within the proximal tubules in mouse kidney. Results of immunohistology and Northern blot showed that the ICAM-1 expression was markedly reduced in the obstructed kidney after treatment with ICAM-1 ASON. The ASON also alleviated the infiltration of inflammatory cells and accumulation of the extracellular matrix in the tubulointerstitium of UUO mice without apparent side effects.

CONCLUSION

Our data demonstrate that ICAM-1 ASON is taken up primarily by the proximal tubular cells of mouse kidney. ICAM-1 ASON can selectively inhibit the ICAM-1 expression of the renal tubular cells both in vitro and in vivo.

Berberine modulates expression of mdr1 gene product and the responses of digestive track cancer cells to Paclitaxel

Berberine is the major constituent of Coptis chinese and is commonly used in Chinese herbal medicine to treat patients with gastrointestinal disorders. In this study, using flow cytometry, we have found that a 24-h berberine treatment up-regulated the multidrug-resistant transporter (pgp-170) expression in two oral (KB, OC2), two gastric (SC-M1, NUGC-3) and two colon (COLO 205, CT 26) cancer cell lines. Decreased retention of rhodamine 123 was observed in berberine-treated cells as compared to vehicle control. To examine whether the berberine modulated pgp-170 expression in cancer cells is associated with changes in drug resistance, we determined the cytotoxicity, cell cycle progression and cell morphology of Paclitaxel-treated cells. Paclitaxel (1 nM-10 microM) treatment for 24 h induced cytotoxicity in OC2, SC-M1 and COLO 205 cells in a dose-dependent manner. Pretreatment of cells with 32 microM berberine for 24 h prior to Paclitaxel treatment resulted in increased viability as compared to that of Paclitaxel-treated cells. In addition, Paclitaxel-induced apoptosis and/or G2/M arrest in these three cancer cell lines. Pretreatment of cells with berberine prior to Paclitaxel blocked the Paclitaxel-induced cell cycle responses and morphological changes. These results together suggest that berberine modulated the expression and function of pgp-170 that leads to reduced response to Paclitaxel in digestive track cancer cells.

Anti-tumor effect of angiogenesis inhibitor TNP-470 on the human nasopharyngeal carcinoma cell line NPC/HK1

The efficacy and targeting cells of angiogenesis inhibitor TNP-470 on human squamous cell nasopharyngeal carcinoma (NPC) were investigated. The colorimetric MTT assay was used to evaluate the IC50 values of NPC/HK1 cells and human dermal microvascular endothelial cells (HDMEC) for TNP-470. An NPC human tumor model was built by tumor-bearing nude mice using the NPC cell line of NPC/HK1. TNP-470 (30 mg/kg s.c.) was injected every other day. The results showed that the IC50 of NPC/HK1 cells for TNP-470 was 3.8 times higher than that of HDMEC. A significant difference in tumor volume between control and treatment groups was found after 7 days of treatment and increased thereafter. At the end of the treatment, tumor volume was 773.7 +/- 287.1 mm3 (n = 8) in the control group versus 454.5 +/- 132.8 mm3 (n = 8) in the treatment group (p = 0. 013); the ratio of the mean tumor volume in treated animals to that of control animals was 0.587, resulting a 41.3% decrease in tumor growth. The necrotic area was larger in the treatment group. Physical toxicity did not result from the treatment. These studies suggest that angiogenesis inhibitor TNP-470 is effective in the treatment of squamous cell NPC without obvious toxicity.

N-Nitrosodimethylamine-mediated cytotoxicity in a cell line expressing P450 2E1: evidence for apoptotic cell death

N-Nitrosodimethylamine (NDMA) is an acute hepatotoxin and potent carcinogen. The metabolic activation of NDMA to reactive metabolites is a critical step for the expression of its toxic and carcinogenic potential. We have previously demonstrated a strong correlation between methylation of cellular macromolecules and NDMA-mediated cytotoxicity, and we have demonstrated that reactive oxygen species may partially contribute to the toxic effects in P450 2E1-expressing cells. The mode of cell death in NDMA-treated monolayer cultures exhibited the following characteristics: (i) condensation of nuclear chromatin as demonstrated by using Hoechst 33258 staining, (ii) DNA fragmentation as detected by combining pulsed field and conventional agarose gel electrophoresis, and (iii) DNA double strand breaks determined by using the in situ terminal deoxynucleotidyl transferase assay and flow cytometric analysis. These results indicate that reactive metabolites of NDMA trigger activation of the signal pathway for apoptotic cell death in these P450-expressing cells. The NDMA-mediated cell death was partially prevented by the endonuclease inhibitor, aurintricarboxylic acid, as well as the caspase inhibitors, acetyl-Asp-Glu-Val-Asp-CHO and acetyl-Tyr-Val-Ala-Asp-CHO. The cell cycle distribution was altered in NDMA-treated cells resulting in an increase in the G2/M phase and a decrease in the G1 phase. Our results suggest that DNA degradation, the inability to complete DNA repair, the biochemical events associated with G2/M arrest, and the process of apoptotic death all result from P450 2E1-catalyzed metabolism of NDMA.

Up-regulation of multidrug resistance transporter expression by berberine in human and murine hepatoma cells

BACKGROUND

Berberine, one of the major constitutents of alkaloids of Coptis chinensis is frequently utilized in the treatment of inflammation and liver-related diseases. In Chinese herbal medicine, Coptis chinensis is used as a prophylactic drug to treat gastrointestinal disorders. In a previous study, the authors found that berberine reduced cell proliferation and alpha-fetoprotein expression in human hepatoma HepG2 cells. Multidrug resistance transporter (pgp-170) is known to be overexpressed in HepG2 cells. Whether berberine regulates the expression of pgp-170 in HepG2 and other hepatoma cell lines is unknown and worthy of investigation.

METHODS

Human and murine hepatoma cells were treated with berberine (0.32, 3.2, 32, and 320 microM), tamoxifen (1 microM), or verapamil (10 microM) for 24 hours. Flow cytometry was used to measure retention of a fluorescence dye, rhodamine 123, and the level of immunoreactive pgp-170 in berberine-treated hepatoma cells.

RESULTS

Berberine up-regulated the expression of pgp-170 in three human hepatoma cell lines. The function of pgp-170 was blocked by tamoxifen and verapamil, resulting in increased retention of rhodamine 123. Retention of rhodamine 123 was significantly reduced in berberine-treated hepatoma cells.

CONCLUSIONS

Berberine modulates the expression and function of pgp-170 in hepatoma cells. These results suggest that treatment of tumor cells with berberine may result in reduced retention of chemotherapeutic agents.

Plasma surface modification of synthetic absorbable sutures

The aim of the study was to examine the feasibility of using plasma surface modification technology to alter the hydrolytic degradation rate of commercial synthetic absorbable sutures. Size 2-0 Dexon, Vicryl, PDSII, and Maxon sutures were tested. They were treated by two different surface modification techniques: parylene deposition and plasma gases (Methane, trimethylsilane, and tetrafluoroethene). The thickness of surface treatment ranged from 200 to 1000 A. The treated sutures were subject to in vitro hydrolytic degradation in phosphate buffer of pH = 7.4 at 37 degrees C for up to 120 days. The tensile breaking strength, weight loss, surface wettability, bending stiffness, and surface morphology were evaluated. The results indicated that the concept of plasma surface treatment for altering the hydrolytic degradation of synthetic absorbable sutures was feasible, and the level of improvement depended on the type of sutures, the treatment conditions, and the duration of hydrolysis. Vicryl and PDSII sutures showed overall the best improvement in tensile strength retention among the four commercial sutures. Dexon and Maxon sutures, however, exhibited only marginal improvement. The observed improvement in tensile strength retention appeared to be related to the increasing hydrophobicity of the sutures. The surface treatments did not adversely affect the bending stiffness of the sutures and no visible surface morphological changes were observed. Refinements and optimization of the surface treatment conditions are needed for achieving the maximum advantage of the proposed concept, particularly shielding the harmful effect of uv during plasma treatment.

Folate deficiency induces a cell cycle-specific apoptosis in HepG2 cells

The human hepatoma HepG2 cell line was chosen as a representative of solid tissue-derived cell systems in which folate metabolism and apoptosis induction have not been thoroughly investigated. HepG2 cells were cultivated in the control or folate-deficient media (control media lacking of folate, glycine, thymidine and hypoxanthine) for 4 wk. This resulted in a decrease in intracellular folate levels to 32% of the control within 1 wk, which was followed by growth arrest and greater cell death rates. These disturbances of folate deficiency coincided with apoptotic induction, as characteristically shown by nucleosomal DNA fragmentation of 180-200 base pair multimers, nuclear chromatin condensation and positive terminal transferase-mediated dUTP nick end labeling assay. Apoptosis coincided with an accumulation of cells in S-phase, a subsequent G2/M phase block and a significant increase in mean protein content as evaluated by flow cytometric analyses employing a double-staining method. The growth and cell cycle arrest under folate-deficient conditions was independent of a change of p53 expression as measured by an enzyme-linked immunosorbent assay. Supplementation of 2 micromol/L folate normalized cell cycles and diminished DNA fragmentation. Taken together, these data indicate that HepG2 cells cultivated in folate-deficient medium have a low folate concentration, decreased growth and viability, and increased apoptotic propensity. This occurrence of apoptosis was associated with a cell cycle-specific mechanism and independent of p53-mediated pathway.