In vivo toxicity of nano-alumina on mice neurobehavioral profiles and the potential mechanisms

The rapid development and expanding applications of nanotechnology have led to enhanced exposure of human body to nanoparticles. It is, therefore, necessary to address the safety issue via rigorous toxicological evaluation and to understand the underlying interaction mechanism. However, only a few studies to date have evaluated the safety of nano-sized materials and their potential adverse effects on biological systems. In this study, we sought to investigate the potential toxicity of aluminum oxide (alumina) nanoparticles in ICR strained mice, focusing on potential neurobehavioral defects and the possible mechanisms. The results demonstrated that nano-alumina impaired neurobehavioral functions, including lengthened escape latency, shorter time spent in the target quadrant and reductions in the number of platform crossing. In addition, it induced cell necrosis and apoptosis, which were likely mediated by the reduction of MMP and ROS, and the induction of the caspase-3 gene. Our results implicated that mitochondrial impairment plays a key role in neurotoxicity of nano-alumina, sequent oxidative damage and neural cell loss, especially necrosis, may be direct causes for the neurobehavioral defects. Collectively, nano-alumina presents a strong pro-cell death effect on ICR mice in vivo, suggesting that nano-alumina may serve as an inducer for neural toxicology. Findings in the present study indicating that surface chemical characteristics and nanoscale sizes of nano-alumina could co-contribute significantly to neurotoxicity. The impaired neurobehavioral patterns indicate that nano-alumina particles are more toxic to the cerebrum than those of nano-carbon with the same nanoparticle size and micro-alumina with the same surface chemical characteristics.

Removal of methylene blue from water by gamma-MnO2

Methylene blue (MB) is a cationic dyestuff, which is particularly resistant to biodegradation. The molecular sieved gamma-MnO2 was used as an adsorbent/oxidant to remove the MB at room temperature and in visible light. The removal efficiency was mainly evaluated by X-ray diffractometer (XRD), UV-Vis spectrometer (UV-Vis), total organic carbon (TOC). The results revealed that the mechanisms of MB removal by gamma-MnO2 are significantly influenced by the pH. In acidic conditions, hypsochromic effects (i.e. blue shifts of UV-Vis spectra) resulting from N-demethylation of the dimethylamino group in MB may occur concomitantly with oxidative degradation by gamma-MnO2. However, the TOC in solution after gamma-MnO2 treatment in acidic conditions did not show a dramatic decrease. At near neutral pH conditions, there was almost no UV-Vis absorption for the MB solution, however, only 50% TOC removal was observed. It indicated that MB was not only adsorbed onto gamma-MnO2 but also partially oxidatively degraded to other organic compounds which were colourless for UV-Vis.

Expression of 53BP1 as a cisplatin-resistant marker in patients with lung adenocarcinomas

DNA repair is one of the major causes of spontaneous drug and radiation resistance in patients with lung adenocarcinomas (LADC). 53BP1 is a mediator that relays signals from DNA damage sensors and activates various effectors for the DNA repair and cell survival. In this study we investigated the clinical and biological significance of 53BP1. Expression of 53BP1 was detected by immunoblotting and immunohistochemistry. Our data showed that 53BP1 was detected in 166 (75.8%) of 219 LADC patients. Expression of 53BP1 correlated with tumor stage, cigarette smoking, lymphovascular invasion and poor clinical outcome. In vitro, increased 53BP1 expression elevated drug resistance, and silencing of 53BP1 expression reduced cisplatin resistance. Our results suggest that 53BP1 expression plays an important role in cisplatin resistance and predicts the prognosis for LADC.

Use of serial pig body weights for genetic evaluation of daily gain

This study examined the utility of serial weights from FIRE (Feed Intake Recording Equipment, Osborne Industries, Inc., Osborne, KS, USA) stations for an analysis of daily gain. Data included 884 132 body weight records from 3888 purebred Duroc pigs. Pigs entered the feeder station at age 77-149 days and left at age 95-184 days. A substantial number of records were abnormal, showing body weight close to 0 or up to twice the average weight. Plots of body weights for some animals indicated two parallel growth curves. Initial editing used a robust regression, which was a two-step procedure. In the first step, a quadratic growth curve was estimated assuming small or 0 weights for points far away from the curve; the process is iterative. In the second step, weights more than 1.5 SD from the estimated growth curve were treated as outliers. The retained body weight records (607,597) were averaged to create average daily weight (170,443) and then used to calculate daily gains (152,636). Additional editing steps included retaining only animals with >or=50 body weight records and SD of the daily gain <or=2 kg, followed by removing records outside 3 SD from the mean for given age, across all the animals - the resulting data set included 69,068 records of daily gain from 1921 animals. Daily gain based on daily, weekly and bi-weekly intervals was analysed using repeatability models. Heritability estimates were 0.04, 6 and 9%, respectively. The last two estimates correspond to heritability of 28% for a 12 week interval. For daily gain averaged weekly, the estimate of heritability obtained with a random regression model varied from 0.07 to 0.10. After extensive editing, body weight records from automatic feeding stations are useful for genetic analyses of daily gain from weekly or bi-weekly but not daily intervals.

Genetic analyses of stillbirth in relation to litter size using random regression models

Estimates of genetic parameters for number of stillborns (NSB) in relation to litter size (LS) were obtained with random regression models (RRM). Data were collected from 4 purebred Duroc nucleus farms between 2004 and 2008. Two data sets with 6,575 litters for the first parity (P1) and 6,259 litters for the second to fifth parity (P2-5) with a total of 8,217 and 5,066 animals in the pedigree were analyzed separately. Number of stillborns was studied as a trait on sow level. Fixed effects were contemporary groups (farm-year-season) and fixed cubic regression coefficients on LS with Legendre polynomials. Models for P2-5 included the fixed effect of parity. Random effects were additive genetic effects for both data sets with permanent environmental effects included for P2-5. Random effects modeled with Legendre polynomials (RRM-L), linear splines (RRM-S), and degree 0 B-splines (RRM-BS) with regressions on LS were used. For P1, the order of polynomial, the number of knots, and the number of intervals used for respective models were quadratic, 3, and 3, respectively. For P2-5, the same parameters were linear, 2, and 2, respectively. Heterogeneous residual variances were considered in the models. For P1, estimates of heritability were 12 to 15%, 5 to 6%, and 6 to 7% in LS 5, 9, and 13, respectively. For P2-5, estimates were 15 to 17%, 4 to 5%, and 4 to 6% in LS 6, 9, and 12, respectively. For P1, average estimates of genetic correlations between LS 5 to 9, 5 to 13, and 9 to 13 were 0.53, -0.29, and 0.65, respectively. For P2-5, same estimates averaged for RRM-L and RRM-S were 0.75, -0.21, and 0.50, respectively. For RRM-BS with 2 intervals, the correlation was 0.66 between LS 5 to 7 and 8 to 13. Parameters obtained by 3 RRM revealed the nonlinear relationship between additive genetic effect of NSB and the environmental deviation of LS. The negative correlations between the 2 extreme LS might possibly indicate different genetic bases on incidence of stillbirth.

The 5p15.33 locus is associated with risk of lung adenocarcinoma in never-smoking females in Asia

Genome-wide association studies of lung cancer reported in populations of European background have identified three regions on chromosomes 5p15.33, 6p21.33, and 15q25 that have achieved genome-wide significance with p-values of 10⁻⁷ or lower. These studies have been performed primarily in cigarette smokers, raising the possibility that the observed associations could be related to tobacco use, lung carcinogenesis, or both. Since most women in Asia do not smoke, we conducted a genome-wide association study of lung adenocarcinoma in never-smoking females (584 cases, 585 controls) among Han Chinese in Taiwan and found that the most significant association was for rs2736100 on chromosome 5p15.33 (p = 1.30×10⁻¹¹). This finding was independently replicated in seven studies from East Asia totaling 1,164 lung adenocarcinomas and 1,736 controls (p = 5.38×10⁻¹¹). A pooled analysis achieved genome-wide significance for rs2736100. This SNP marker localizes to the CLPTM1L-TERT locus on chromosome 5p15.33 (p = 2.60×10⁻²⁰, allelic risk = 1.54, 95% Confidence Interval (CI) 1.41–1.68). Risks for heterozygote and homozygote carriers of the minor allele were 1.62 (95% CI; 1.40–1.87), and 2.35 (95% CI: 1.95–2.83), respectively. In summary, our results show that genetic variation in the CLPTM1L-TERT locus of chromosome 5p15.33 is directly associated with the risk of lung cancer, most notably adenocarcinoma.

Worldwide, approximately 15% of lung cancer cases occur among nonsmokers. Genome-wide association studies (GWAS) of lung cancer conducted in populations of European background have identified three regions on chromosomes 5, 6, and 15 that harbor genetic variants that confer risk for lung cancer. Prior studies were conducted primarily in cigarette smokers, raising the possibility that the associations could be related to tobacco use, lung carcinogenesis, or both. A GWAS of lung cancer among never-smokers is an optimal setting to discover effects that are independent of smoking. Since most women in Asia do not smoke, we conducted a GWAS of lung adenocarcinoma among never-smoking females (584 cases, 585 controls) in Taiwan, and observed a region on chromosome 5 significantly associated with risk for lung cancer in never-smoking women. The finding was independently replicated in seven studies from East Asia totaling 1,164 lung adenocarcinomas and 1,736 controls. To our knowledge, this study is the first reported GWAS of lung cancer in East Asian women, and together with the replication studies represents the largest genetic association study in this population. The findings provide insight into the genetic contribution of common variants to lung carcinogenesis.

Inflammatory myofibroblastic tumor of the lung--a case report

A 45-year-old man presented with a six-month history of progressive dyspnea with productive cough and wheezing. The patient was a heavy smoker and had a history of tongue cancer, hypertension, and asthma. Chest X-ray and computed tomography showed a mass lesion in the left hilar region and total collapse of the upper left lobe of the lung. Bronchoscopy revealed a whitish solid tumor obstructing the left upper lobe bronchus. Positron emission tomography showed increased tracer uptake in the lesion. A thoracoscopic lobectomy of the left upper lobe of the lung was performed. The final pathologic diagnosis was inflammatory myofibroblastic tumor.

A novel xylene substitute for histotechnology and histochemistry

Propylene glycol methyl ether (PGME) exhibits excellent solvent and coupling properties. A toxicity database provided evidence suggesting that PGME might be a useful substitute for xylene in histotechnology and histochemistry applications. Tissue specimens were fixed, cleared in either PGME or xylene, embedded in paraffin wax, then dewaxed in either PGME or xylene. Sections were treated with the following stains: hematoxylin & eosin (H & E), three special stains of the Gordon/Sweet silver staining method, PAS, and Masson's trichrome, and immunostains including actin, CD3, CD34, CK, CK7/CK9, Ki-67, and ER/PR. The sections were mounted in a resinous medium consisting of PGME and pinene copolymer, then examined under a microscope. Variables such as water tolerance, dimension change, organic solvency, and anti-fading efficacy also were assessed. Depending on the application, PGME performance was equal to or exceeded that of xylene. PGME provided better optical clarity and nuclear detail, did not harden the tissue samples, conserved tissue antigenicity, and was amenable to resinous mounting. Tissues not dehydrated with absolute ethanol also were processed properly. Tissues treated with PGME did not warp or contract compared to those treated with xylene (p < 0.0001). PGME, however, exhibited less organic solvency than xylene. There was no discernible change in the colors of stains in sections processed with PGME even after storage for two years. These results suggest that PGME is a novel xylene substitute for applications in histotechnology and histochemistry.

p53R2 expression as a prognostic biomarker in early stage non-small cell lung cancer

p53R2 is a small subunit of ribonucleotide reductase (RR) which has 80% homology to hRRM2 and metastasis-suppressing potential. Previous reports suggested that the expression of p53R2 is used as a prognostic factor and chemotherapy response indicator in several types of cancer. This study aimed to elucidate the association of p53R2 expression and the clinicopathological characteristics of early stage non-small cell lung cancer (NSCLC). Immunohistochemistry was conducted on a tissue array including 92 early stage NSCLC samples. Correlations between p53R2 and clinicopathological factors, recurrence/metastasis and outcomes were analyzed. The analyses showed that there was no correlation between p53R2 expression and the clinicopathological factors. Among disease-free patients during follow-up, patients with p53R2(+) had a better outcome than those with p53R2(-) (P=0.022). By using Cox multivariate regression analysis, p53R2 (risk factor 3.801; 95% CI 1.004-9.454; P=0.044) served as a prognostic biomarker in the prediction of the survival rate for NSCLC patients. Detection of the RR subunit p53R2 may therefore be a useful prognostic marker in early stage NSCLC.

Dysregulation of p53/Sp1 control leads to DNA methyltransferase-1 overexpression in lung cancer

Overexpression of DNA 5'-cytosine-methyltransferases (DNMT), which are enzymes that methylate the cytosine residue of CpGs, is involved in many cancers. However, the mechanism of DNMT overexpression remains unclear. Here, we showed that wild-type p53 negatively regulated DNMT1 expression by forming a complex with specificity protein 1 (Sp1) protein and chromatin modifiers on the DNMT1 promoter. However, the stoichiometry between p53 and Sp1 determined whether Sp1 acts as a transcription activator or corepressor. Low level of exogenous Sp1 enhanced the repressive activity of endogenous p53 on the DNMT1 promoter whereas high level of Sp1 upregulated DNMT1 gene expression level in A549 (p53 wild-type) cells. In H1299 (p53 null) cells, exogenous Sp1 induced DNMT1 expression in a dose-dependent manner. We also discovered a new mechanism whereby high level of Sp1, via its COOH-terminal domain, induced interaction between p53 and MDM2, resulting in degradation of p53 by MDM2-mediated ubiquitination. Clinical data from 102 lung cancer patients indicated that overexpression of DNMT1 was associated with p53 mutation (P = 0.014) and high expression of Sp1 protein (P = 0.006). In addition, patients with overexpression of both DNMT1 and Sp1 proteins showed poor prognosis (P = 0.037). Our cell and clinical data provided compelling evidence that deregulation of DNMT1 is associated with gain of transcriptional activation of Sp1 and/or loss of repression of p53. DNMT1 overexpression results in epigenetic alteration of multiple tumor suppressor genes and ultimately leads to lung tumorigenesis and poor prognosis.

Biodegradation of propionitrile by Klebsiella oxytoca immobilized in alginate and cellulose triacetate gel

A microbial process for the degradation of propionitrile by Klebsiella oxytoca was studied. The microorganism, K. oxytoca, was isolated from the discharged wastewater of metal plating factory in southern Taiwan and adapted for propionitrile biodegradation. The free and immobilized cells of K. oxytoca were then examined for their capabilities on degrading propionitrile under various conditions. Alginate (AL) and cellulose triacetate (CT) techniques were applied for the preparation of immobilized cells. The efficiency and produced metabolic intermediates and end-products of propionitrile degradation were monitored in bath and continuous bioreactor experiments. Results reveal that up to 100 and 150 mM of propionitrile could be removed completely by the free and immobilized cell systems, respectively. Furthermore, both immobilized cell systems show higher removal efficiencies in wider ranges of temperature (20-40 degrees C) and pH (6-8) compared with the free cell system. Results also indicate that immobilized cell system could support a higher cell density to enhance the removal efficiency of propionitrile. Immobilized cells were reused in five consecutive degradation experiments, and up to 99% of propionitrile degradation was observed in each batch test. This suggests that the activity of immobilized cells can be maintained and reused throughout different propionitrile degradation processes. A two-step pathway was observed for the biodegradation of propionitrile. Propionamide was first produced followed by propionic acid and ammonia. Results suggest that nitrile hydratase and amidase were involved in the degradation pathways of K. oxytoca. In the continuous bioreactor, both immobilized cells were capable of removing 150 mM of propionitriles completely within 16h, and the maximum propionitriles removal rates using AL and CT immobilized beads were 5.04 and 4.98 mM h(-1), respectively. Comparing the removal rates obtained from batch experiments with immobilized cells (AL and CT were 1.57 and 2.18 mM h(-1) at 150 mM of propionitrile, respectively), the continuous-flow bioreactor show higher potential for practical application.

Sorption of toluene by humic acids derived from lake sediment and mountain soil at different pH

Contamination of soil and groundwater with BTEX compounds (benzene, toluene, ethylbenzene, and xylene) depends on the sorption behavior of these compounds by soil organic matter (SOM) and humic acids (HAs). In this study sorption of toluene by HAs extracted from lake sediment and mountain soil was investigated. HA suspensions were adjusted to pH 4.00, 6.00, or 8.00 and made to the concentration of 200 mg L(-1). Each HA suspension or solution was subjected to particle size analysis using high performance particle sizer (HPPS). The particle size of HA from lake sediment was around 1000-1200 nm while that from mountain soil was 220-320 nm at suspension pH 4.00. Kinetic studies showed that sorption of toluene by the two HAs followed pseudo-first-order and mainly pseudo-zero-order kinetics. At suspension pH 4.00, the sorption of toluene by the two HAs was best described by Langmuir and Temkin adsorption isotherm models. Further, sorption of toluene by the lake sediment HA was significantly greater than that by mountain soil HA. It was thus suggested that the lake sediment HA with larger particle size may develop beneficially chemical conformation for sorption of toluene and related compounds in soil and associated environments.

Molecular detection of Muscovy duck parvovirus by loop-mediated isothermal amplification assay

Muscovy duck parvovirus (MDPV) usually causes high morbidity and mortality in 1- to 3-wk-old Muscovy ducklings due to serious infections, which is an imminent threat to the commercial duck industry in China. The objectives of this study were to develop and evaluate a simple, rapid, and inexpensive loop-mediated isothermal amplification (LAMP) method for specific detection of MDPV and to compare it with the PCR method in rapidity, sensitivity, and accuracy. The novel LAMP assay used a set of 4 specific primers to recognize 6 distinct genomic sequences of capsid protein (VP3) from MDPV, which could be completed within 50 min at 63 degrees C in a simple water bath. The diagnostic results demonstrated that the LAMP assay detected all 7 preserved MDPV isolates, had no cross-reactivity with other duck pathogens (i.e., goose parvovirus, duck plague virus, H9N2 avian influenza virus, duck hepatitis type virus I, and Muscovy duck reovirus). The LAMP assay was at least 10-fold more sensitive than the routine PCR assay and obtained more sensitivity in 61 clinical samples. Therefore, the newly developed LAMP assay provides a specific and sensitive means for detecting MDPV and can be simply applied both in field conditions and in laboratory operations in a cost-effective manner with primary care facilities.

Abstract 1862: Inactivation of P53 by HPV 16/18 E6 proteins in lung cancer is correlated with P53 codon 72 genotypes

A polymorphism at codon 72 of the p53 tumor suppressor gene is as a possible determinant for cancer risk and particularly carcinomas associated with HPV infection. Our recent report has shown that high-risk HPV 16/18 E6 proteins were associated with p53 protein degradation in lung cancer. To address the relationship of the different p53 genotypes and HPV oncoprotein expression in p53 protein degradation of lung cancer, 141 primary lung cancer patients were included in this study. PCR-RFLP, nested-PCR and immunohistochemial analysis were used to detect the p53 codon 72 polymorphism, HPV 16/18 infection, HPV 16/18 E6 and p53 protein expression. Our data showed that HPV 16/18 E6 protein but not HPV 16/18 DNA were reversely correlated with p53 expression, which was further confirmed by tissue in situ immunostaining. Additionally, the frequency of p53 protein negative expression in HPV 16/18 E6-positive/Arg homozygosity lung cancer tumors is much higher than that in the other three categorizes. This correlation was not found in HPV DNA infection. In conclusion, HPV 16/18 E6 proteins involvement in p53 inactivation to contribute to HPV-infected lung tumorigenesis is correlated with p53 codon 72 genotypes.

Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1862.

First Report of Fruit Rot of Loquat Caused by an Alternaria sp. in Taiwan

During March 2007, a fruit rot disease was observed in several loquat (Eriobotrya japonica (Thunberg) Lindley) fields located in Taichung, Nantou, and Miaoli counties. Loquat is a valuable fruit crop grown predominantly in central Taiwan, and hence, even a minor yield loss by this new disease is economically significant. Symptoms on fruits initially appeared as small lesions (<1 mm) that later developed into light-to-dark brown, circular, larger (7 mm), sunken lesions, indicating invasion of a pathogen into the fruit. Pieces of rotted fruit tissue (1 × 1 × 1 mm) were immersed for 1 min in 3% commercial bleach, followed by 70% ethanol, cultured on potato dextrose agar (PDA), and incubated under constant fluorescent light (185 ± 35 μE·m^-2·s^-1) at 24°C for 2 days. Three single conidial isolates (AS1 to AS3) were selected and used in morphological and pathogenicity studies. All three isolates were identified as an Alternaria sp. (1-3) and formed abundant, dark brown mycelium when cultured on PDA with light at 24°C. Conidiophores were 60 to 89 × 3 to 5 μm, densely fasciculate, cylindrical, simple or branched, and had distinct conidial scars. Conidia were 12 to 74 × 6 to 14 μm, golden brown, straight or curved, obclavate with beaks measuring half the length of the conidium, and observed in chains of 10 or more spores with four to seven transverse septa and several longitudinal septa. Pathogenicity tests were conducted twice by inoculating eight surface-sterilized wounded or unwounded fruits with each of the three isolates in each experiment. Two cuts (1 × 1 × 1 mm) were made on each fruit 3 cm apart with a sterile scalpel, and a 300-μl spore suspension (2 × 10⁵ conidia per ml) was placed on each wound. Similarly, a 300-μl spore suspension was placed on unwounded fruits and air dried for 5 min. Control fruits were similarly treated with sterile water. Inoculated fruits were enclosed in a plastic bag and kept at 24 ± 1°C. Symptoms of soft rot were observed on 60% (unwounded) and 100% (wounded) of inoculated fruits 5 days after inoculation, while control fruits did not develop disease symptoms. Reisolation from the symptomatic fruits consistently yielded an Alternaria sp. This fungus previously has been reported as the causal agent of fruit rot or black spot of papaya, mango, kiwifruit, pear, and carambola from Australia, India, Malaysia, South Africa, and the United States (1-3). To our knowledge, this is the first report of fruit rot of loquat caused by an Alternaria sp. in Taiwan. To manage this disease, growers may resort to fungicidal sprays followed by bagging of fruits to reduce pre- and postharvest losses. References: (1) A. L. Jones and H. S. Aldwinckle. Compendium of Apple and Pear Diseases. The American Phytopathological Society. St. Paul, MN, 1990. (2) R. C. Ploetz. Diseases of Tropical Fruit Crops. CABI Publishing. Wallingford, Oxfordshire, UK, 2003. (3) R. C. Ploetz et al. Compendium of Tropical Fruit Diseases. The American Phytopathological Society. St. Paul, MN, 1994.

ATPase family AAA domain-containing 3A is a novel anti-apoptotic factor in lung adenocarcinoma cells

AAA domain-containing 3A (ATAD3A) is a member of the AAA-ATPase family. Three forms of ATAD3 have been identified: ATAD3A, ATAD3B and ATAD3C. In this study, we examined the type and expression of ATAD3 in lung adenocarcinoma (LADC). Expression of ATAD3A was detected by reverse transcription-polymerase chain reaction, immunoblotting, immunohistochemistry and confocal immunofluorescent microscopy. Our results show that ATAD3A is the major form expressed in LADC. Silencing of ATAD3A expression increased mitochondrial fragmentation and cisplatin sensitivity. Serum deprivation increased ATAD3A expression and drug resistance. These results suggest that ATAD3A could be an anti-apoptotic marker in LADC.

The effect of intertube van der Waals interaction on the stability of pristine and functionalized carbon nanotubes under compression

This paper investigates the effect of intertube van der Waals interaction on the stability of pristine and covalently functionalized carbon nanotubes under axial compression, using molecular mechanics simulations. After regulating the number of inner layers of the armchair four-walled (5, 5)@(10, 10)@(15, 15)@(20, 20) and zigzag four-walled (6, 0)@(15, 0)@(24, 0)@(33, 0) carbon nanotubes, the critical buckling strains of the corresponding tubes are calculated. The results show that each of the three inner layers in the functionalized armchair nanotube noticeably contributes to the stability of the outermost tube, and together increase the critical strain amplitude by 155%. However, the three inner layers in the corresponding pristine nanotube, taken together, increase the critical strain of the outermost tube by only 23%. In addition, for both the pristine and functionalized zigzag nanotubes, only the (24, 0) layer, among the three inner layers, contributes to the critical strain of the corresponding outermost tube, by 11% and 29%, respectively. The underlying mechanism of the enhanced stability related to nanotube chirality and functionalization is analyzed in detail.

Role of citric acid in the formation of silver nanoplates through a synergistic reduction approach

This study discusses the function of citrate ions in the synthesis of silver nanoplates through a synergetic reduction approach in ambient conditions. It was found that the citrate ions can play multiple roles in the synthesis process, including a reducing agent, a stabilizer, and a complex agent, and they show some unique features under the reported conditions. The reducing ability of these citrate ions was shown to be weaker than that of sodium borohydride and/or L-ascorbic acid used in the same system. The stability in the shape/size control of silver particles is weaker than that of other surfactants tested in the present system, such as bis(2-ethylhexyl)sulfosuccinate (AOT) and thiols. Citrate ions could form a silver complex with silver ions as [Ag(2)(+)...citrate] or [Ag(3)(C(6)H(5)O(7))(n+1)](3n-), as confirmed by electrospray ionization (ESI) mass spectrometry and the kinetic analysis that the molar ratio of citric acid or sodium citrate to silver ions can greatly influence the reaction rate and, hence, the particle growth of silver nanoparticles. Such a complexing effect is further confirmed by the use of chelating ions (e.g., [Fe(CN)(6)](4-)) to form Ag(n)[Fe(CN)(6)](n-4), which can largely influence the synthesis of silver nanoparticles. These results show some formation results of generating silver nanoplates involving citrate ions, which are useful in the shape-controlled synthesis of other metallic nanoparticles with desirable functionalities.

Elevated serum dehydroepiandrosterone sulphate level correlates with increased risk for metabolic syndrome in the elderly men

BACKGROUND

The previous studies regarding the association between endogenous dehydroepiandrosterone (DHEA) sulphate level and metabolic syndrome are inconsistent. This study aimed to investigate such relationship in elderly Taiwanese men.

MATERIALS AND METHODS

Five hundred and eighty-five elderly Taiwanese men (mean age 68.7 +/- 8.3 years) were enrolled as the baseline cohort population in 2000. In addition to a questionnaire, body mass index (BMI), blood pressure, fasting blood glucose, lipids, albumin and serum DHEA-S levels were measured for each participant. Metabolic syndrome was based on the definition by the America Heart Association/National Heart Lung Blood Institute.

RESULTS

The prevalence of metabolic syndrome was 33.3%. Using multivariate logistic regression analyses with adjustments for age, smoking, alcohol, physical activities, albumin and BMI, there was a positive relationship between serum DHEA-S level and metabolic syndrome. The highest DHEA-S quartile group had increased risk for metabolic syndrome (odds ratio = 2.68, 95% confidence interval: 1.44-5.01, P < 0.01) compared with the lowest quartile group. The mean serum DHEA-S level increased with increasing number of metabolic syndrome components.

CONCLUSIONS

The prevalence of metabolic syndrome increases with elevated DHEA-S levels among elderly Taiwanese men. Thus, elevated serum DHEA-S level should be treated as an important risk factor for metabolic syndrome in elderly men.

The tobacco-specific carcinogen NNK induces DNA methyltransferase 1 accumulation and tumor suppressor gene hypermethylation in mice and lung cancer patients

DNA methyltransferase 1 (DNMT1) catalyzes DNA methylation and is overexpressed in many human diseases, including cancer. The tobacco-specific carcinogen NNK also induces DNA methylation. However, the role of DNMT1-mediated methylation in tobacco carcinogenesis remains unclear. Here we used human and mouse lung cancer samples and cell lines to determine a mechanism whereby NNK induced DNMT1 expression and activity. We determined that in a human lung cell line, glycogen synthase kinase 3beta (GSK3beta) phosphorylated DNMT1 to recruit beta-transducin repeat-containing protein (betaTrCP), resulting in DNMT1 degradation, and that NNK activated AKT, inhibiting GSK3beta function and thereby attenuating DNMT1 degradation. NNK also induced betaTrCP translocation to the cytoplasm via the heterogeneous nuclear ribonucleoprotein U (hnRNP-U) shuttling protein, resulting in DNMT1 nuclear accumulation and hypermethylation of the promoters of tumor suppressor genes. Fluorescence immunohistochemistry (IHC) of lung adenomas from NNK-treated mice and tumors from lung cancer patients that were smokers were characterized by disruption of the DNMT1/betaTrCP interaction and DNMT1 nuclear accumulation. Importantly, DNMT1 overexpression in lung cancer patients who smoked continuously correlated with poor prognosis. We believe that the NNK-induced DNMT1 accumulation and subsequent hypermethylation of the promoter of tumor suppressor genes may lead to tumorigenesis and poor prognosis and provide an important link between tobacco smoking and lung cancer. Furthermore, this mechanism may also be involved in other smoking-related human diseases.

A polymorphism in the hMLH1 gene (-93G-->A) associated with lung cancer susceptibility and prognosis

Polymorphisms in DNA repair genes may be associated with differences in repair capacity of DNA damage and may thereby influence an individual's susceptibility to lung cancer. We investigated the association between the -93G-->A polymorphism in the mismatch repair hMLH1 gene for its role in the susceptibility and survival of non-small cell lung cancer (NSCLC) patients. Using a case-control study design, 165 NSCLC patients and 193 controls with similar range for age, gender and smoking habit distributions were subjected to genotype analysis. The risk of lung cancer was estimated by logistic regression analysis. The Kaplan-Meier method was used to estimate the probability of survival and the log-rank test was used to assess the significance of the difference between survival probabilities. The homozygous variant A/A genotype was associated with a significantly increased risk for lung cancer compared with the other genotypes (Crude analysis P=0.003, Adjusted analysis P=0.011, using the logistic regression model). The patients with a homozygous variant A/A genotype had a trend toward poorer prognoses compared with other patients, especially smoking (P=0.05, by log-rank test), male (P=0.06), or squamous carcinoma (P=0.08) patients. This is the first case-control study to show a significant association between the hMLH1-93G-->A polymorphism and the susceptibility to and prognosis of lung cancer. The results herein may be useful for risk assessment and disease monitoring of NSCLC.

A prospective study of factors influencing return to work after traumatic spinal cord injury in Taiwan

Lin M-R, Hwang H-F, Yu W-Y, Chen C-Y. A prospective study of factors influencing return to work after traumatic spinal cord injury in Taiwan.

OBJECTIVE

To examine comprehensively the effects of physical, psychologic, and sociologic characteristics on employment among persons after a traumatic spinal cord injury (SCI) in Taiwan.

DESIGN

A prospective study with follow-up telephone interviews over a 3-year period.

SETTING

To register people who had sustained an SCI, medical records of 4 hospitals were reviewed using codes of the International Classification of Diseases-9th Revision-Clinical Modifications from 806.0 to 806.9 and from 952.0 to 952.9.

PARTICIPANTS

Subjects (N=219) employed at the time of injury.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Employment status after an SCI.

RESULTS

The employment rate was 32.9%. After controlling for other variables, education level (relative rate [RR]=4.01 approximately 8.17), autonomy in transportation (RR=5.13), professional licensure (RR=1.86), and thrill and adventure-seeking trait (RR=1.12) were positively and significantly associated with employment, while subjects with more severe overall injury severity (RR=0.95), preinjury chronic conditions (RR=0.20), necessity for aids for daily living (RR=0.31), and depression (RR=0.38) were less likely to have been employed than their counterparts.

CONCLUSIONS

In addition to education level and traditional physical factors, overall injury severity and psychologic factors such as thrill and adventure seeking and depression can also influence the return to work after an SCI.

Lung cancer susceptibility and prognosis associated with polymorphisms in the nonhomologous end-joining pathway genes: a multiple genotype-phenotype study

BACKGROUND

Nonsmall cell lung cancer (NSCLC) frequently exhibits genomic instability, such as high fractional allelic loss (FAL). Genomic instability may result from unrepaired or misrepaired double-strand breaks (DSBs). The authors of this report postulated that polymorphisms in genes of the nonhomologous end-joining (NHEJ) pathway, which is the major DSB repair pathway in mammalian cells, may modulate lung cancer susceptibility and prognosis.

METHODS

Patients with NSCLC (n = 152) and a group of appropriate age-matched and sex-matched controls (n = 162) were subjected to genotype analysis of the NHEJ pathway genes x-ray repair complementing defective repair in Chinese hamster cells 6 (Ku70) (reference single nucleotide polymorphism number [rs] 2267437), x-ray repair complementing defective repair in Chinese hamster cells 5 (Ku80) (rs3835), x-ray repair complementing defective repair in Chinese hamster cells 4 (XRCC4) (rs1805377), and DNA ligase IV (LIG4) (rs1805388). The gene-gene interaction (joint effect), genotype-environmental (ie, smoking) correlation, and genotype-phenotype (ie, FAL) correlation were examined. The Kaplan-Meier method and log-rank tests were used to assess the prognostic effect.

RESULTS

There was a significant association between the XRCC4 and LIG4 genotypes with NSCLC risk in an analysis of individual polymorphism associations, and the risk of NSCLC increased further in a combined analysis of multiple polymorphisms (adjusted odds ratio [OR], 8.74). The patients who had a homozygous variant guanine/guanine genotype of the XRCC4 gene had a poorer prognosis compared with other patients (P = .015). There was a significant difference between the patient smokers and controls for XRCC4 (adjusted OR, 2.67) and LIG4 (adjusted OR, 2.04). In addition, polymorphisms in XRCC4 and LIG4 were linked significantly with patients who had high FAL (adjusted OR, 2.03-3.84).

CONCLUSIONS

To the authors' knowledge, this is the first nested case-control study to demonstrate a significant association between the polymorphisms of genes in the NHEJ pathway and lung cancer susceptibility and prognosis. The results may be useful for risk assessment and disease monitoring of patients with NSCLC.

The structural and optical properties of InN nanodots grown with various V/III ratios by metal-organic chemical vapor deposition

Self-assembled InN nanodots have been prepared at 650 degrees C with various V/III ratios from 500 to 30 000 by metal-organic chemical vapor deposition (MOCVD). It is found that the dot density and morphological size as well as the optical properties all display drastic changes at V/III = 12 000. Generally, denser and smaller InN nanodots with higher emission energy and narrower linewidth were obtained when growth was conducted at V/III ratios slightly lower than 12 000 as compared to those at higher V/III ratios. The physical properties of our MOCVD-grown InN nanodots are sensitive to the surface structure and the morphology is very similar to molecular beam epitaxially grown GaN and InN films, which may be used as a guide to optimize the InN growth.

Treatment results and late complications of 556 patients with locally advanced nasopharyngeal carcinoma treated with radiotherapy alone

The aim of this study was to investigate the outcome in 556 patients with locally advanced nasopharyngeal carcinomas treated by radiation therapy alone. We observed 556 patients with stage T3-4 and N0-3 carcinoma who were treated by conventional radiotherapy alone between January and December 1999. The total dose delivered to the nasopharynx was 66-80 Gy over 6.5-8 weeks and to the neck lymph nodes 60-70 Gy over 6-7 weeks. The 5-year actuarial overall survival rate (OS) reached 66.41%. The OS was higher among stage T3 patients than among stage T4 patients (69.12% vs 58.96%, p = 0.0359). Among patients with stage N0, N1, N2 and N3 disease, the OS was 73.98%, 65.96%, 57.58% and 29.39%, respectively (p = 0.0009). Differences in disease-free survival, locoregional control rate and metastasis-free survival rate among each N stage were statistically significant, although this was not true of differences between stage T3 and T4 disease. Multivariate analysis showed that gender, age, T stage and N stage were significant prognostic factors for 5-year overall survival, disease-free survival, locoregional control and metastasis-free survival. We found that N stage is the dominant prognostic indicator for patients with locally advanced nasopharyngeal carcinoma receiving conventional radiation therapy alone, and that T stage was only a secondary correlative factor.

First Report of Stem-End Rot of Mango Caused by Phomopsis mangiferae in Taiwan

Mango (Mangifera indica L.) is grown on approximately 20,000 ha in Taiwan. It is an economically important crop and the income of many fruit farmers comes primarily from mango production. During 2006 and 2007, a stem-end rot disease was observed 1 week after harvest on 28 to 36% of stored mangoes picked from six orchards in the Pingtung, Tainan, and Kaoshiung regions. Two popular mango cultivars, Keitt and Irwin, showed greater susceptibility to this disease, while 'Haden' was found to be moderately susceptible. In storage, symptoms initially appeared as light-to-dark brown lesions surrounding peduncles. Rot symptoms advanced slowly but eventually penetrated the mesocarp, which consequently reduced the commercial value of fruits. The fungus formed abundant pycnidia (0.1 to 0.6 mm in diameter) on infected fruits in advanced stages of symptom development. Pieces of symptomatic fruits plated on acidified potato dextrose agar (PDA) and incubated at 25 ± 1°C consistently yielded the same fungus. A single conidial isolate was cultured. Pycnidia developed on PDA after continuous exposure to light for 9 to 14 days. On the basis of morphological characteristics, the fungus was identified as Phomopsis mangiferae L. (2,3). Pycnidia released two types of conidia: α-conidia (5 to 10 × 2.3 to 4.0 μm) were hyaline and oval to fusoid; and β-conidia (15.0 to 37.5 × 1.3 to 2.5 μm) were hyaline and filiform with characteristic curves. Conidiophores were hyaline, filiform, simple or branched, septate, and 15 to 75 μm long. Cultures incubated under continuous fluorescent light (185 ± 35 μE·m^-2·s^-1) at 25°C for 3 days were used as inoculum for pathogenicity tests. Five fruits from 'Keitt' were wounded with a sterilized scalpel and each wound (2 × 2 × 2 mm) was inoculated with either a 5-mm mycelium agar plug or a 0.5-ml spore suspension (10⁵ conidia per ml) of the fungus. Five wounded fruits inoculated with 5-mm PDA plugs or sterile water alone served as controls. Inoculated areas were covered with moist, sterile cotton. Fruits were enclosed in plastic bags and incubated at 24°C for 3 days. The test was performed three times. The same symptoms were observed on all inoculated fruits, whereas no decay was observed on control fruits. Reisolations from the inoculated fruits consistently yielded P. mangiferae, thus fulfilling Koch's postulates. This disease has previously been reported in Australia, Brazil, China, Cuba, India, Malaysia, and the United States (1). To our knowledge, this is the first report of P. mangiferae causing stem-end rot disease on mangoes in Taiwan. Our report necessitates taking preventive strategies in the field, prior to or after harvest, to contain postharvest losses in mangoes. References: (1) G. I. Johnson. Page 39 in: Compendium of Tropical Fruit Diseases. R. C. Ploetz et al., eds. The American Phytopathological Society. St. Paul, MN, 1994. (2) R. C. Ploetz, ed. Page 354 in: Diseases of Tropical Fruit Crops. CABI Publishing. Wallingford, UK, 2003. (3) E. Punithalingam. No. 1168 in: Descriptions of Pathogenic Fungi and Bacteria. CMI, Kew, Surrey, UK, 1993.

O6-Methylguanine-DNA methyltransferase hypermethylation modulated by 17beta-estradiol in lung cancer cells

BACKGROUND

Our recent report indicated that MGMT hypermethylation is more common in squamous cell carcinomas (SCC) in males, and smokers than in adenocarcinomas (ADC) in females, and nonsmokers. More interestingly, MGMT hypermethylation in SCC and ADC was pronouncedly influenced by gender factor, not by smoking status. We questioned whether 17beta-estradiol could modulate the machinery of promoter methylation to cause the gender difference of MGMT hypermethylation in lung cancer.

MATERIALS AND METHODS

Two MGMT hypermethylated Ch27 and H1355 lung cancer cell lines were treated with or without 17beta-estradiol and the status of hypermethylation was examined by methylated specific methylation (MSP) as compared with both cells treated with demethylating agents, 5-AZA-dC (AZA) or TSA.

RESULTS

Our data showed that 17beta-estradiol, similar to AZA, diminished the MGMT hypermethylation and restored MGMT mRNA expression, which was not observed in the case of TSA. Western blotting showed that 17beta-estradiol markedly reduced DNMT1 expression in Ch27 and H1355 cells, but slightly reduced HDAC1 expression. Consequently, acetylated H3 and H4 histone levels were slightly increased by 17beta-estradiol in both cell types. In addition, ChIP analysis revealed that 17beta-estradiol simultaneously diminished the binding activity of both proteins on the MGMT promoter of both cell lines.

CONCLUSION

17beta-Estradiol decreased DNMT1 and HDAC1 protein expressions and their binding activity on MGMT promoter, and this may partially contribute to the gender difference of MGMT hypermethylation in lung cancer.

IL-10 promoter gene polymorphisms and sustained response to combination therapy in Taiwanese chronic hepatitis C patients

BACKGROUND AND AIMS

Host genetic factors may affect clinical outcomes of hepatitis C virus (HCV) infection; however, the possible mechanisms remain largely unknown. The role of immunopathogenesis in chronic hepatitis C leads to extensive exploration of host immunity including inflammatory cytokines.

METHODS

We examined interleukin 10 (IL-10) promoter gene polymorphisms at positions -1082, -819, and -592 relative to transcription start site and studied their association with response to 24 weeks of pegylated interferon plus ribavirin treatment in 143 chronic hepatitis C patients, of whom 97 (67.8%) achieved a sustained virologic response (SVR). In addition, 134 healthy adults were used as controls.

RESULTS

Of chronic hepatitis C patients, 111 (77.6%) were genotype 1 infection, 32 (22.4%) were genotype 2 infection. Patients with sustained virologic response were younger and had higher pretreatment ALT levels than those without. No statistical difference was found between chronic hepatitis C patients who achieved SVR or not in terms of gender, HCV genotype, pretreatment HCV RNA levels, and severity of liver disease. The serum IL-10 levels were comparable between healthy controls and chronic hepatitis C patients as well as between HCV patients with and without SVR. The distribution of IL-10 promoter gene polymorphisms at positions -1082, -819, and -592 relative to transcription start site was comparable between HCV patients and healthy controls as well as HCV patients with and without SVR. A high frequency of ATA haplotype of common IL-10 promoter gene SNPs was found in both chronic hepatitis C patients (70.3%) and healthy controls (69.8%). However, ATA haplotype was not associated with SVR in chronic hepatitis C patients.

CONCLUSIONS

Our data fail to demonstrate the influence of IL-10 promoter gene polymorphisms on the response to combination therapy in Taiwanese chronic hepatitis C patients. The impact of genetic variations in IL-10 haplotype on the response to anti-HCV treatment among different ethnic populations deserves further examination.

Enhanced mechanical properties of single-walled carbon nanotubes due to chemical functionalization

Recent studies have shown that the chemical functionalization of carbon nanotubes weakens most of their mechanical properties such as the critical buckling force under compression and the critical buckling moment under torsion. However, the mechanical properties including the critical bending curvature and the critical bending moment of single-walled carbon nanotubes can be improved after functionalization as shown in this paper. The molecular mechanics simulations reveal that there exists an optimum functionalization degree at which the critical curvatures of the functionalized carbon nanotubes reaches its maximum value. The critical curvatures of the carbon nanotubes increase with increasing functionalization degree below the optimum value, while the critical curvatures change little as the functionalization degree is beyond the optimum value. The influences of the bending directions and the aspect ratios of the functionalized carbon nanotubes are also examined via molecular mechanics simulations.

Potential increase in the prognostic value of p53 mutation by Pro72 allele in stage I non-small-cell lung cancer

BACKGROUND

Accumulated evidence suggests that p53 function altered by its gene mutation or genetic polymorphism contributes to tumor malignancy. Association of p53 mutation and its codon 72 polymorphism with lung cancer prognosis has been extensively studied. However, the joint effect of p53 mutation and p53 codon 72 polymorphism on lung cancer prognosis remains uncertain.

METHODS

In the present study, 266 primary lung cancer patients were included and overall survival was calculated. Genomic DNA prepared from adjacent normal lung and lung tumor tissues was used to determine p53 codon 72 genotype and p53 mutation by polymerase chain reaction (PCR) restriction fragment length polymorphism (RFLP) and direct sequencing, respectively.

RESULTS

For all stages, neither p53 codon 72 genotype nor p53 mutation is associated with lung cancer prognosis. However, stage I patients with p53 mutation had a 1.79-fold hazard ratio [95% confidence interval (CI) 1.04-3.10] for overall survival when compared with p53 wild-type patients. Notably, stage I patients with p53 mutation and p53 codon 72 Pro/Pro genotype experienced a 2.66-fold hazard ratio (95% CI 1.21-5.85) for overall survival when compared with those with p53 wild-type and Arg/Arg genotype. An increased prognostic value was not observed in stage I patients with p53 wild-type and p53 Pro72 allele or in those with p53 mutation and p53 codon 72 Arg/Arg genotype.

CONCLUSIONS

We therefore suggest that p53 codon 72 Pro allele potentially increases the prognostic value of p53 mutation in stage I non-small-cell lung cancer.

ZnO/Al2O3 core-shell nanorod arrays: growth, structural characterization, and luminescent properties

We report an aqueous chemical method to fabricate well-aligned ZnO/Al(2)O(3) nanocrystal (NC) core-shell nanorod arrays (NRAs). Structural characterization showed that the shell layers are composed of alpha-Al(2)O(3) nanocrystals. Photoluminescence measurements showed the enhancement of near-band-edge (NBE) emission of ZnO NRAs due to the presence of Al(2)O(3) NC shells. The Al(2)O(3) NC shell layer resulting in the flat-band effect near the ZnO surface leads to a stronger overlap of the wavefunctions of electrons and holes in the ZnO core, further enhancing the NBE emission. This approach should be very useful in designing many other core-shell NRAs for creating varieties of high-efficiency optoelectronic devices.

Electrical and optoelectronic characterization of a ZnO nanowire contacted by focused-ion-beam-deposited Pt

We report on the transport properties of a single ZnO nanowire (NW) measured as a function of the length/square of the radius ratio via the transmission line method (TLM). The specific contact resistance of FIB-Pt contacts to the ZnO NWs is determined to be as low as 1.1 x 10(-5) Omega cm(2). The resistivity of the ZnO NWs is measured to be 2.2 x 10(-2) Omega cm. ZnO NW-based UV photodetectors contacted by FIB-Pt with a photoconductive gain as high as approximately 10(8) have been fabricated and characterized.

Polymer functionalized ZnO nanobelts as oxygen sensors with a significant response enhancement

A plasma-polymerized acrylonitrile (PP-AN)/ZnO nanobelt (NB) nanosensor reveals a better oxygen-sensing response than a bare ZnO NB nanosensor due to the sorption nature of the polymer. With the aid of UV light, significant response enhancements of PP-AN/ZnO NB nanosensors at low temperature have been observed since the effects of oxygen desorption/adsorption in PP-AN on the electron depletion region in the ZnO are significant. The minimum sensitivity at 150 degrees C is 16.6 ppm. This work permits its feasibility in areas where it is impossible to work at higher temperatures since lowering the working temperature of the sensor can avoid the structural deterioration, causing instability in the response.

Association between expression of human papillomavirus 16/18 E6 oncoprotein and survival in patients with stage I non-small cell lung cancer

The clinical significance of HPV-16/18 E6 oncoprotein expression in non-small cell lung cancer (NSCLC) is not fully known. A study was undertaken to investigate the association between expression of human papillomavirus 16/18 E6 oncoprotein and survival in patients with stage I NSCLC. We analyzed a series of 217 patients with stage I NSCLC for the presence of HPV-16/18 E6 oncoprotein by immunohistochemistry. HPV-16 E6 oncoprotein was expressed in 49 (22.6%) patients and HPV-18 E6 oncoprotein was expressed in 31 (14.3%) patients. Statistical analysis revealed that the prevalence of expression of HPV-16 and HPV-18 E6 oncoproteins was significantly high in female patients, nonsmokers and patients with adenocarcinoma. The adjusted odds ratio for expression of HPV-16 E6 oncoprotein in female patients was 2.275 [95% confidence interval (CI), 0.999-5.179] and that in patients with adenocarcinoma was 2.320 (95% CI, 1.029-5.232). These ratios were significantly higher than those in male patients and patients with squamous cell carcinoma. Interestingly, we found that the 17 patients who expressed HPV-16 and HPV-18 E6 oncoprotein had a higher 5-year cumulate survival rate (72.2%) than the 154 patients who did not express both oncoproteins (48.3%); the difference was significant (p=0.055). Expression of HPV-16/18 E6 oncoprotein in stage I NSCLC may play an important role in female adenocarcinoma patients and survival benefits in patients who expressed HPV-16 and HPV-18 E6 oncoprotein.

Anemia treatment with Q2W darbepoetin alfa in patients with chronic kidney disease naïve to erythropoiesis-stimulating agents

OBJECTIVE

To evaluate the efficacy and safety of darbepoetin alfa dosed every-other-week (Q2W) to treat anemia in subjects with chronic kidney disease (CKD), not receiving dialysis, who were naïve to erythropoiesis-stimulating agent (ESA) therapy.

RESEARCH DESIGN AND METHODS

This was an open-label, multicenter, single-arm study enrolling ESA-naïve CKD subjects with baseline hemoglobin (Hb) < 11.0 g/dL. Q2W darbepoetin alfa treatment was initiated at a dose of 0.75 microg/kg and titrated to achieve and maintain Hb levels at 11.0-13.0 g/dL. Treatment was administered from week 1 to week 19.

MAIN OUTCOME MEASURES

The primary endpoint was the proportion of subjects who achieved Hb > or = 11 g/dL at any study visit, except in week 1. Hb levels, darbepoetin alfa dose, and safety were also assessed.

RESULTS

Of the 128 subjects who received at least one dose of darbepoetin alfa and of the subjects who completed the study, 118 (92%) and 112 (97%), respectively, achieved a Hb > or = 11 g/dL in a median time of 5 weeks. Median darbepoetin alfa dose at week 1 and at the time of achieving a Hb > or = 11 g/dL were 60 and 80 microg, respectively. Darbepoetin alfa was well-tolerated, and short-term adverse events were consistent with those expected in CKD subjects.

CONCLUSIONS

This study demonstrates that de novo Q2W darbepoetin alfa was effective in correcting and maintaining Hb levels in ESA-naïve subjects with CKD who were not receiving dialysis. Study limitations, including lack of a control arm for the study and multiple race information for subjects, must be considered in interpreting the results.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, NCT00112008.

Prognostic significance of X-ray cross-complementing group 1 T-77C polymorphism in resected non-small cell lung cancer

OBJECTIVE

A novel T-77C polymorphism in the promoter region of the DNA repair gene X-ray cross-complementing group 1 (XRCC1) may modulate its transcription to increase the risk of lung cancer. Here, we attempt to clarify: (i) whether the XRCC1 T-77C polymorphism was associated with lung cancer risk in Taiwanese and (ii) whether this polymorphism could act as a prognostic indicator to predict the clinical outcome of non-small-cell lung cancer (NSCLC) patients.

METHODS

A total of 294 primary lung cancer patients and 288 potential controls were recruited into our study. Clinical data were collected. The genotypes of XRCC1 T-77C were identified by polymerase chain reaction.

RESULTS

Our case-control study showed that the XRCC1 T-77C polymorphism was not associated with the risk of lung cancer in Taiwanese patients. To verify the impact of the XRCC1 T-77C polymorphism on the clinical outcome of NSCLC, survival analysis showed that patients with TT had a lower survival rate than those with the TC + CC genotype (33.1% versus 48.8%, P = 0.031). The Cox regression analysis further indicated that patients with the TT genotype had a 1.84-fold risk compared with those with the TC + CC genotype (95% CI, 1.16-2.86, P = 0.008).

CONCLUSION

Our results suggest that XRCC1 T-77C variants (TC + CC) may act as a favorable prognostic indicator of resected NSCLC.

High precision high voltage divider and its application to electron beam ion traps

A high precision high voltage divider has been developed for the electron beam ion trap in Shanghai. The uncertainty caused by the temperature coefficient of resistance (TCR) and the voltage coefficient of resistance has been studied in detail and was minimized to the level of ppm (10(-6)) range. Once the TCR was matched between the resistors, the precision of the dividing ratio finally reached the ppm range also. We measured the delay of the divider caused by the capacitor introduced to minimize voltage ripple to be 2.35 ms. Finally we applied the divider to an experiment to measure resonant energies for some dielectronic recombination processes for highly charged xenon ions. The final energies include corrections for both space charge and fringe field effects are mostly under 0.03%.

Osteopontin increases lung cancer cells migration via activation of the alphavbeta3 integrin/FAK/Akt and NF-kappaB-dependent pathway

Tumor malignancy is associated with several features such as proliferation ability and frequency of metastasis. Osteopontin (OPN), which is abundantly expressed in bone matrix, is involved in cell adhesion, migration, invasion and cell proliferation via interaction with its receptor, alphavbeta3 integrin. However, the effect of OPN on migration activity in human lung cancer cells is mostly unknown. Here we found that OPN increased the migration via activation of alphavbeta3 integrin in human lung cancer cells (A549 cells). Phosphatidylinositol 3-kinase inhibitor (PI3K; Ly294002), Akt inhibitor or ERK inhibitor (PD98059) inhibited the OPN-induced increase in the migration of lung cancer cells. OPN stimulation increased the phosphorylation of focal adhesion kinase (FAK), p85 subunit of PI3K, serine 473 of Akt and ERK. In addition, treatment of A549 cells with NF-kappaB inhibitor (PDTC) or IkappaB protease inhibitor (TPCK) inhibited OPN-induced migration of lung cancer cells. Stimulation of A549 cells with OPN also induced IkappaB kinase alpha/beta (IKK alpha/beta) phosphorylation, IkappaBalpha phosphorylation, p65 Ser(536) phosphorylation, and kappaB-luciferase activity. The OPN-mediated increases in IKK alpha/beta, IkappaBalpha and p65 Ser(536) phosphorylation were inhibited by Ly294002, Akt inhibitor and PD98059. Co-transfection with FAK, p85, Akt and ERK mutants also reduced the OPN-induced kappaB-luciferase activity. Taken together, these results suggest that OPN acts through alphavbeta3 integrin, which in turn activates the FAK, PI3K, Akt, ERK and NF-kappaB pathways, contributing to the migration of lung cancer cells.

Multiple stressor effects of herbicide, pH, and food on wetland zooplankton and a larval amphibian

Interactions of herbicides and natural environmental stressors such as pH and food availability are poorly understood. We tested a chemical formulation of triclopyr (Release) at environmentally relevant test concentrations (0.25 and 0.50 mg L(-1)) in combination with two levels of pH (pH 5.5 and 7.5), and two levels of food availability (high and low). Population level effects of each stressor alone and in combination with the others were investigated using Simocephalus vetulus, a zooplankton species, and Rana pipiens tadpoles (Gosner stage 25), both common to forest ponds and wetlands. Herbicide treatments resulted in significant decreases in survival of both test species as well as reproduction and development time for S. vetulus at levels 5-10x below predicted worst case environmental concentrations (2.6 mg L(-1)). This laboratory study demonstrates a probable risk of toxic effects of Release herbicide which may be significantly increased by low food availability and by low pH at environmentally relevant concentrations.

Impacts of peripheral obestatin on colonic motility and secretion in conscious fed rats

Obestatin, a novel putative 23-amino acid peptide, was found to be derived from a mammalian preproghrelin gene by using a bioinformatics approach. Although the effects of obestatin on food intake and upper gut motility remain controversial, no studies have been carried out to explore its influence on lower gut motility and secretion. We investigated the impacts of intravenous (IV) injection of obestatin on rat colonic motor and secretory functions. Colonic transit time, fecal pellet output, and fecal content were measured in freely fed, conscious rats, which were chronically implanted with IV and colonic catheters. To test the validity of this animal model, human/rat corticotropin-releasing factor (h/rCRF) served as a stimulatory inducer of colonic motility and secretion. IV injection of obestatin (45, 100, and 300 nmol/kg) did not affect the colonic transit time, whereas IV injection of h/rCRF (30 nmol/kg) effectively accelerated colonic transit time. IV obestatin, in every dose we tested, also did not modify fecal pellet output, frequency of watery diarrhea, total fecal weight, fecal dried solid weight, or fecal fluid weight in the first hour after injection. On the other hand, IV injection of h/rCRF significantly enhanced fecal pellet output, as well as increased the frequency of watery diarrhea, total fecal weight, fecal dried solid weight, and fecal fluid weight during the first hour after injection compared with IV saline controls. In conclusion, peripheral obestatin administration has no impact on colonic motility and secretion in conscious fed rats.

In vivo differentiation of aerobic brain abscesses and necrotic glioblastomas multiforme using proton MR spectroscopic imaging

BACKGROUND AND PURPOSE

Abscesses caused by aerobic bacteria (aerobic abscesses) can simulate intracranial glioblastomas multiforme (GBMs) in MR imaging appearance and single voxel (SV) proton MR spectroscopy of the central cavity. The purpose of our study was to determine whether MR spectroscopic imaging (SI) can be used to differentiate aerobic abscesses from GBMs. Our hypothesis was that metabolite levels of choline (Cho) are decreased in the ring-enhancing portion of abscesses compared with GBMs.

MATERIALS AND METHODS

Fifteen patients with aerobic abscesses were studied on a 1.5T MR scanner using an SV method and an SI method. Proton MR spectra of 15 GBMs with similar conventional MR imaging appearances were used for comparison. The resonance peaks in the cavity, including lactate, cytosolic amino acids, acetate, succinate, and lipids, were analyzed by both SV MR spectroscopy and MRSI. In the contrast-enhancing rim of each lesion, peak areas of N-acetylaspartate (NAA), choline (Cho), lipid and lactate (LL), and creatine (Cr) were measured by MRSI. The peak areas of NAA-n, Cho-n, and Cr-n in the corresponding contralateral normal-appearing (-n) brain were also measured. Maximum Cho/Cr, Cho/NAA, LL/Cr-n, and Cho/Cho-n and minimum Cr/Cr-n and NAA/NAA-n ratios in abscesses and GBMs were compared using the Wilcoxon rank sum test. After receiver operating characteristic curve analysis, diagnostic accuracy was compared.

RESULTS

Cytosolic amino acid peaks were found in the cavity in 7 of 15 patients with aerobic abscesses. Means and SDs of maximum Cho/Cr, Cho/NAA, LL/Cr-n, and Cho/Cho-n and minimum Cr/Cr-n and NAA/NAA-n ratios were 3.38 +/- 1.09, 3.88 +/- 2.13, 2.72 +/- 1.45, 1.98 +/- 0.53, 0.53 +/- 0.16, and 0.44 +/- 0.09, respectively, in the GBMs, and 1.77 +/- 0.49, 1.48 +/- 0.51, 2.11 +/- 0.67, 0.81 +/- 0.21, 0.48 +/- 0.2, and 0.5 +/- 0.15, respectively, in the abscesses. Significant differences were found in the maximum Cho/Cr (P = .001), Cho/NAA (P = .006), and Cho/Cho-n ratios (P < .001) between abscesses and GBMs. Diagnostic accuracy was higher by Cho/Cho-n ratio than Cho/Cr and Cho/NAA ratios (93.3% versus 86.7% and 76.7%).

CONCLUSION

Metabolite ratios and maximum Cho/Cho-n, Cho/Cr, and Cho/NAA ratios of the contrast-enhancing rim were significantly different and useful in differentiating aerobic abscesses from GBMs by MRSI.