Syngas generation from n-butane with an integrated MEMS assembly for gas processing in micro-solid oxide fuel cell systems

An integrated system of a microreformer and a carrier allowing for syngas generation from liquefied petroleum gas (LPG) for micro-SOFC application is discussed. The microreformer with an overall size of 12.7 mm × 12.7 mm × 1.9 mm is fabricated with micro-electro-mechanical system (MEMS) technologies. As a catalyst, a special foam-like material made from ceria-zirconia nanoparticles doped with rhodium is used to fill the reformer cavity of 58.5 mm(3). The microreformer is fixed onto a microfabricated structure with built-in fluidic channels and integrated heaters, the so-called functional carrier. It allows for thermal decoupling of the cold inlet gas and the hot fuel processing zone. Two methods for heating the microreformer are compared in this study: a) heating in an external furnace and b) heating with the two built-in heaters on the functional carrier. With both methods, high butane conversion rates of 74%-85% are obtained at around 550 °C. In addition, high hydrogen and carbon monoxide yields and selectivities are achieved. The results confirm those from classical lab reformers built without MEMS technology (N. Hotz et al., Chem. Eng. Sci., 2008, 63, 5193; N. Hotz et al., Appl. Catal., B, 2007, 73, 336). The material combinations and processing techniques enable syngas production with the present MEMS based microreformer with high performance for temperatures up to 700 °C. The functional carrier is the basis for a new platform, which can integrate the micro-SOFC membranes and the gas processing unit as subsystem of an entire micro-SOFC system.

Small molecule inhibitors of STAT3 for cancer therapy

Aberrant activation of the signal transducer and activator of transcription (STAT) 3 occurs in many human tumors. Constitutive STAT3 activity induces specific target genes that stimulate cell proliferation, prevent apoptosis, promote angiogenesis and facilitate tumor immune evasion. Thus, STAT3 is an attractive molecular target for the development of novel cancer therapeutics. Targeting and disruption of oncogenic STAT3 signaling may theoretically be accomplished through various approaches, involving direct and indirect strategies. Small molecular weight compounds have been used for this purpose. This review is intended to be full coverage of the small molecular inhibitors to develop direct STAT3 as a target for cancer therapy and will provide a discussion on the inhibitory modalities developed to date. At present, we retrieved related small molecular inhibitors experimental research papers about STAT3 as a cancer therapy target, the rationale to pursue the protein for the discovery and development of novel anticancer strategies and agents.

Condom use, intervention service utilization and HIV knowledge among female sex workers in China: results of three consecutive cross-sectional surveys in Shandong Province with historically low HIV prevalence

Heterosexual transmission of HIV through contact with female sex workers (FSWs) is a growing concern for the HIV/AIDS epidemic in China. Using consecutive cross-sectional surveys, we examined the prevalence of HIV and sexually transmitted infections (STIs), risk behaviours, HIV knowledge and the utilization of intervention services among FSWs in Shandong Province. Of 3460 participants, half reported ever having STI-related symptoms, 57.8% had ≥7 clients in the last week, half reported inconsistent use of condoms with clients and 11.2% reported ever using illicit drugs. Consistent use of condoms with clients was associated with higher education, being 20-24 years of age, being recruited from hotels, having ever received free condoms and was inversely associated with STI-related symptoms. HIV-related knowledge was associated with higher education, ever testing for HIV and inversely associated with self-reported STI-related symptoms. The low rates of condom use, high number and frequent turnover of clients, high prevalence of self-reported STIs and drug use highlight the urgency for more effective intervention in these FSWs.

Preliminary experience of endoscopic submucosal tunnel dissection for upper gastrointestinal submucosal tumors

BACKGROUND AND STUDY AIM

Although the majority of submucosal tumors (SMTs) are benign, some do have a malignant potential. Resection of SMTs would aid in establishing the diagnosis and may be curative. Our aim was to examine the feasibility and safety of a novel method for endoscopic resection of upper gastrointestinal SMTs.

PATIENTS AND METHODS

In 12 patients who presented with an upper gastrointestinal SMT of ≤40 mm located in the esophagus or cardia, a submucosal tunnel was endoscopically created starting approximately 5 cm proximal to the lesion. After careful submucosal dissection with carbon dioxide or air insufflation, the SMTs were completely removed, and the entrance of the tunnel closed using endoclips.

RESULTS

SMTs had a mean size of 19.5 mm (range 10-40 mm); eight were located in the esophagus and four in the cardia. SMT resection was successful in all patients with en bloc resection in 10 patients (83.3%) and resection in two pieces in the remaining two patients. The mean time required for the procedure was 48.3 minutes (range 30-60 minutes). Two patients had both pneumothorax and subcutaneous emphysema. All the complications resolved with conservative management.

CONCLUSIONS

In this pilot study, endoscopic submucosal tunnel dissection (ESTD) of esophageal and cardia SMTs was effective and appeared to be safe. Larger studies that also examine its application for gastric SMTs are warranted.

Grape seed proanthocyanidins extracts promote apolipoprotein A-I mRNA expression in HepG2 cells under experimental sugar and high-sugar conditions

OBJECTIVES

In this study, we investigated the effect of grape seed proanthocyanidins extracts (GSPE), which have been proved to have anti-oxidative and anti-aging functions, on the expression of apoA-L at mRNA level of HepG2 cells in vitro under the experimental conditions of high-sugar and sugar.

MATERIALS AND METHODS

Cell viability was measured by sulforhodamine B (SRB). The apoA-I mRNA expression was assayed by real-time fluorescence quantitative polymerase chain reaction. Firstly, HepG2 cells were incubated in 10% inactivated newborn calf serum in Dulbecco's Modified Eagle Medium (DMEM). Next, cells were incubated with high-sugar and sugar serum-free medium, and added different concentration of GSPE (2.5, 5 and 10 microg/ml) for more than 24 hours, and thereafter, investigated whether GSPE can promote more apoA-I expression in HepG2 cells under the experimental conditions of high-sugar and sugar.

RESULTS

In this experiment, HepG2 cells were incubated with high-sugar and sugar serum-free medium, and HepG2 cells incubated with high-sugar medium produced less apoA-I at mRNA level. The difference was significant (p < 0.05). When HepG2 cells were incubated with GSPE at concentration of 20 microg/ml or above for about 4 hours, cell viability measured by SRB was lower than 50%. However, cell viability of HepG2 cells incubated with GSPE at concentration of 10 microg/ml or below was higher than 70%. Therefore, we chose the HepG2 cells incubated with GSPE concentration of 2.5, 5, 10 microg/ml to observe the effect of GSPE on the mRNA expression of apoA-I. After incubated with GSPE, the apoA-I expression of HepG2 cells were significantly elevated at mRNA level compared to that of high sugar control (p < 0.05). Moreover, this action of GSPE showed dose dependent, and the dose of 2.5 microg/ml was optimal.

CONCLUSIONS

GSPE (concentration of higher than 20 microg/ml) could inhibit HepG2 cell survival, and in HepG2 cells, endogenous apoA-I was significantly suppressed following 24h of exposure to high concentrations of glucose. Meanwhile GSPE could promote expression of apoA-L dose dependently at mRNA level when its concentration was lower than 10 microg/ml.

Quantitative determination of pidotimod in human plasma by liquid chromatography tandem mass spectrometry: application to a bioequivalence study

A highly sensitive and simple LC-MS/MS method after one-step protein precipitation was developed and validated for determination of pidotimod (CAS 121808-62-6) in human plasma using dextrophan (CAS 125-73-5) as internal standard (IS). Pidotimod and IS were separated on a YMC-ODS-AQ C18 column using 0.5% formic acid and methanol as a mobile phase at a flow rate of 0.3 mL/min. Detection was performed on positive ion mode of the transitions at 245.0→134.0 for pidotimod and 258.1→157.0 for IS by selected reaction monitoring (SRM). The assay exhibited a linear range of 0.05-10.0 µg/mL. The lower limit of quantification were 0.05 µg/mL. Validation results indicated that the accuracy as determined from quality control samples was in the range of  - 4.00-6.48%. Intra-day and inter-day precision was ≤  8.35% and ≤  8.00%, respectively. The developed method was successfully applied to a bioequivalence study in 20 healthy Chinese volunteers following a single oral dose of 800 mg pidotimod. The simple, inexpensive protein precipitation and high-throughput method makes it a suitable and valuable tool in the investigation of the clinical pharmacokinetics and bioequivalence.

Serum detection of epidermal growth factor receptor gene mutations using mutant-enriched sequencing in Chinese patients with advanced non-small cell lung cancer

Epidermal growth factor receptor gene (EGFR) mutations are among the best predictive markers of the efficacy of EGFR tyrosine kinase inhibitor (EGFR-TKI) treatment. Mutations in the EGFR gene confer sensitivity to EGFR-TKIs in patients with advanced non-small cell lung cancer (NSCLC). This study determined the concordance rate of EGFR mutations in serum samples and tumour tissue from Chinese patients with advanced NSCLC and compared two detection methods: mutant-enriched polymerase chain reaction-based DNA sequencing and non-enriched sequencing. The EGFR mutation status in serum was consistent with that in paired tumour samples, with a concordance rate of 93.1% for mutant-enriched sequencing. In serum samples, mutant-enriched sequencing demonstrated sensitivity and specificity of 77.8% and 100%, respectively, and was more sensitive than the non-enriched assay. Mutant-enriched sequencing in serum may provide a non-invasive and sensitive method for detecting EGFR mutation status in patients with unresectable NSCLC.

Bioequivalence evaluation of cefdinir in healthy fasting subjects

A simple and sensitive HPLC method was developed to determine cefdinir (CAS 91832-40-5) in human plasma. The method was validated by investigating the accuracy and precision for intra- and inter-day runs in a linear concentration from 0.05-2.0 µg/ml. The object of this study was to compare the bioavailability of cefdinir capsule (reference) and cefdinir granule (test) containing 100 mg of cefdinir. A randomized, open-label, single-dose, 2-way crossover bioequivalence study in 20 healthy, Chinese, male subjects was conducted. A 1-week wash-out period was applied. Blood samples were collected before and with 10 h after drug administration. The formulations were compared using the following pharmacokinetic parameters: AUC0-t, AUC0-∞ and C max. The 90% confidence interval (CI) of the ratios of log-transformed AUC0-t and AUC0-∞ were used to assess bioequivalence between the 2 formulations using the equivalence interval of 80 and 125%. The results showed that the 90% CI of the ratios of AUC0-t, AUC0-∞ and C max were 102.5% (94.7-111.0%), 103.4% (94.8-112.7%) and 106.4% (97.0-116.7%), respectively, which indicated 2 formulations of cefidinir are bioequivalent. Both treatments showed similar tolerability and safety.

Rapid analysis of the quality of the recording coating on ink jet printing in preparation

Preparation of the recording coating on the ink jet printing (RC-IJP) is proposed. The microstructure of RC-IJP was analyzed by scanning electron microscopy and atomic force microscope. The surface infiltration process of RC-IJP was studied. Fourier transform near-infrared (FT-NIR) spectra showed the combination and overtone vibrations information of the hydrogen-containing groups in RC-IJP structure. NIR spectra combined with partial least-squares methods were proposed for the noncontact analysis of the surface infiltration time and weight per unit area in RC-IJP. Forty-five samples were selected for the calibration sets of the surface infiltration time and weight per unit area, respectively. Spectral pretreatment method was used to develop robust calibration models. After the spectral pretreatment was optimized, the determination coefficient (R(2)) of the surface infiltration time and weight per unit area were 0.90 and 0.97, respectively. The analytical results showed that NIR spectra had significant potential for the analysis of the surface infiltration time and weight per unit area of RC-IJP.

STAT3 gene polymorphisms and susceptibility to non-small cell lung cancer

Signal transducer and activator of transcription protein 3 (STAT3) has been implicated in cancer development and is recognized as a type of oncogene. However, association studies of single nucleotide polymorphisms (SNPs) in the STAT3 gene with cancer risk are rare and not available for lung cancer. We examined whether STAT3 polymorphisms are associated with the risk of non-small cell lung cancer (NSCLC). Eight SNPs in the STAT3 gene were genotyped by TaqMan assays in 326 NSCLC cases and 432 controls in a Chinese population. Significant decreased risk of NSCLC was observed for carriers of minor alleles rs4796793 (odds ratio (OR) = 0.68, 95% confidence interval (CI) = 0.51-0.92), rs7211777 (OR = 0.67, 95%CI = 0.50-0.90), rs12949918 (OR = 0.73, 95%CI = 0.54-0.97), rs744166 (OR = 0.69, 95%CI = 0.51-0.92), rs9912773 (OR = 0.75, 95%CI = 0.55-0.98), and rs3869550 (OR = 0.70, 95%CI = 0.53-0.94). The GGCGGC haplotype, comprised of minor alleles of the six NSCLC-associated SNPs, had a 0.78-fold (95%CI = 0.62-0.97) significantly decreased risk of NSCLC, as compared to the most common haplotype of CATACT. Stratification analyses by clinical stage showed that the trend for the association between STAT3 polymorphisms and NSCLC risk was present both for stage I/II and stage III/IV, and appeared moderately stronger for stage III/IV. We conclude that polymorphisms in the STAT3 gene may have a protective role in the development of NSCLC, particular of stage III/IV NSCLC.

Human infection with novel G3P[25] rotavirus strain in Taiwan

Genotype P[25] rotaviruses are rare and to date have been reported to occur only in a few countries of mainland Asia. Here we report the molecular characterization of a novel human rotavirus genotype combination, G3P[25], detected in a 17-month-old child hospitalized due to severe gastroenteritis during 2009 in central Taiwan. Sequencing and phylogenetic analysis of the VP4 gene demonstrated a distinct origin from other strains bearing the P[25] VP4 gene, whereas the VP7, VP6 and NSP4 gene phylogenies identified common origins with cognate genes of other, presumed human-porcine reassortment Taiwanese strains. These results suggest that interactions between human and animal strains appear to contribute to the generation of genetic and antigenic diversity of rotavirus strains, with potential public health importance in Taiwan.

Mitochondrial apoptotic pathways: a mechanism for low androgen-induced vascular endothelial injury in male rats

The aim of the study was to investigate the role of mitochondrial apoptotic pathways in vascular endothelial injury in male rats with low androgen. 8 week-old adult male Sprague-Dawley (SD) rats were randomly divided into 3 groups (n=6/each group): control group, castrated group (low androgen), and replacement group (given androgen after castration). After 10 weeks, endothelial structure was observed by general light microscope and transmission electron microscope (TEM) respectively. Isolated mitochondria and mitochondrial membrane potential (MMP) were detected by fluorescence to access mitochondrial function. Chromatin degradation was measured by terminal deoxynucleotidyl transferase-mediated deoxyuridine-biotin nick end labeling (TUNEL) staining method. The mRNA and protein of bcl-2, cytochrome C (Cyt C), caspase-9, and caspase-3 were analyzed for apoptosis. Cell shrinkage and condensed chromatin, less mitochondria and a fall in MMP levels were observed in the castrated group, along with more apoptotic endothelial cells. Bcl-2 level was reduced and the expression of caspase-9, caspase-3 and Cyt C were elevated in the castrated group (p<0.05). But there was no significant difference between the replacement group and the control group (p>0.05). It was concluded that low androgen caused vascular endothelial damage. It may be, at least in part, related with the activating mitochondrial apoptotic pathways.

Emittance-exchange-based high harmonic generation scheme for a short-wavelength free electron laser

Generation of short-wavelength radiation by a free-electron laser using up-frequency conversion of an electron bunch density modulation is currently an area of active research. We propose a new scheme for producing the longitudinal electron bunch density modulation similar to the recently proposed echo-enabled harmonic generation but based on an emittance exchange beam line and a multislit mask. Beam line analysis and start-to-end simulation are presented.

Achalasia: incidence, prevalence and survival. A population-based study

BACKGROUND

Studies of achalasia epidemiology are important as they often yield new insights into disease etiology. In this study, our objective was to carry out the first North American population-based study of achalasia epidemiology using a governmental administrative database.

METHODS

All residents in the province of Alberta, Canada receive universal healthcare coverage as a benefit. The provincial health ministry, Alberta Health and Wellness, maintains a central stakeholder database of patient demographic information and physician billing claims. We defined an achalasia case as a billing claim submitted for the years 1996-2007 with an ICD-9-CM code of 530.0 or 530 and a Canadian Classification of Procedure treatment code of 54.92A (endoscopic balloon dilation) or 54.6 (esophagomyotomy). A preliminary validation study of the case definition demonstrated a sensitivity of 85% and specificity of 99% for known cases and controls.

KEY RESULTS

A total of 463 achalasia cases were identified from 1995 to 2008 (59.6% males). Mean age at diagnosis was 53.1 years. In 2007, the achalasia incidence was 1.63/100,000 (95% CI 1.20, 2.06) and the prevalence was 10.82/100,000 (95% CI 9.70, 11.93). We observed a steady increase in the overall prevalence rate from 2.51/100,000 in 1996 to 10.82/100,000 in 2007. Survival of achalasia cases was significantly less than age-sex matched population controls (P < 0.0001).

CONCLUSIONS & INFERENCES

Using a population-based approach, the incidence and prevalence of treated achalasia is 1.63/100,000 and 10.82/100,000, respectively. The disease appears to have a stable incidence but a rising prevalence. Survival of achalasia cases is significantly less than age-matched healthy controls.

The profile of KIR3DL1 and KIR3DS1 alleles in an African American population resembles that found in African populations

KIR3DL1 and KIR3DS1 allele frequencies were determined by DNA sequencing of the complete coding regions from 100 random unrelated African Americans. Alleles 3DL1*01501 (29 individuals) and 3DL1*01502 (23 individuals) were most frequently observed in addition to 21 other known alleles and 7 new alleles: KIR3DL1*01503, *03102, *064, *065, *066, *067, and *068. Two of the new alleles (KIR3DL1*064, *065) created additional variants of the chimeric KIR3DL1/KIR3DL2 gene. KIR3DS1*01301 (94% of the gene positive individuals) and KIR3DS1*049N (11%) were identified in the 18 individuals carrying this gene. Three individuals appeared to carry a killer cell immunoglobulin-like receptor haplotype with KIR3DL1/S1 duplication. The profile of alleles resembles that found in African populations but also shows signs of admixture.