Study on the interaction between erythrosine B and the cardiac drug amiodarone using fluorescence,scattering, and absorbance spectra and their analytical application

In an acidic buffered solution, erythrosine B can react with amiodarone to form an association complex, which not only generates great enhancement in resonance Rayleigh scattering (RRS) spectrum of erythrosine B at 346.5 nm but also results in quenching of fluorescence spectra of erythrosine B at λ_emission = 550.4 nm/λ_excitation = 528.5 nm. In addition, the formed erythrosine B–amiodarone complex produces a new absorbance peak at 555 nm. The spectral characteristics of the RRS, absorbance, and fluorescence spectra, as well as the optimum analytical conditions, were studied and investigated. As a result, new spectroscopic methods were developed to determine amiodarone by utilizing erythrosine B as a probe. Moreover, the ICH guidelines were used to validate the developed RRS, photometric, and fluorimetric methods. The enhancements in the absorbance and the RRS intensity and the decrease in the fluorescence intensity of the used probe were proportional to the concentration of amiodarone in ranges of 2.5–20.0, 0.2–2.5, and 0.25–1.75 μg/mL, respectively. Furthermore, limit of detection values were 0.52 ng/mL for the spectrophotometric method, 0.051 μg/mL for the RRS method, and 0.075 μg/mL for the fluorimetric method. Moreover, with good recoveries, the developed spectroscopic procedures were applied to analyze amiodarone in its commercial tablets.     

A new current dipole tracing method from EEG which is very useful in research of human brain activity in the space station

The space station is available from 2004 for scientific research including human physiology and medicine. In that instance, non-invasive research of human brain in the microgravity condition was highly required. The present newly developed dipole tracing method fits this research purpose, by determining current source in the brain from EEG activity. EEG is also very helpful to monitor the conditions of subjects in various hazard cases. We strongly recommend to use this apparatus in the space station.     

Genomic organization of Tropomodulins 2 and 4 and unusual intergenic and intraexonic splicing of YL-1 and Tropomodulin 4

Background

Single nucleotide polymorphisms (SNPs) are the foundation of powerful complex trait and pharmacogenomic analyses. The availability of large SNP databases, however, has emphasized a need for inexpensive SNP genotyping methods of commensurate simpliCity, robustness, and scalability. We describe a solution-based, microtiter plate method for SNP genotyping of human genomic DNA. The method is based upon allele discrimination by ligation of open circle probes followed by rolling circle amplification of the signal using fluorescent primers. Only the probe with a 3' base complementary to the SNP is circularized by ligation.

Results

SNP scoring by ligation was optimized to a 100,000 fold discrimination against probe mismatched to the SNP. The assay was used to genotype 10 SNPs from a set of 192 genomic DNA samples in a high-throughput format. Assay directly from genomic DNA eliminates the need to preamplify the target as done for many other genotyping methods. The sensitivity of the assay was demonstrated by genotyping from 1 ng of genomic DNA. We demonstrate that the assay can detect a single molecule of the circularized probe.

Conclusions

Compatibility with homogeneous formats and the ability to assay small amounts of genomic DNA meets the exacting requirements of automated, high-throughput SNP scoring.     

Effects of oil reservoir conditions on the production of water‐insoluble Levan by Bacillus licheniformis

Bacillus licheniformis produced a water‐insoluble levan which has potential application as a selective plugging agent in microbial enhanced oil recovery (MEOR). The microorganism grew on sucrose, glucose, and fructose but produced levan only on sucrose. Plugging may thus be selectively controlled in the reservoir by substrate manipulation. B. licheniformis and a crude preparation of its extracellular enzymes were evaluated for their ability to produce levan under reservoir conditions. Oil reservoirs which have a temperature of less than 55°C, a pH between 6 and 9, a pressure less than 500 atm, and a salt concentration of 4% or less are potentially suitable. Examples of such reservoir conditions are found in Lloydminster on the Alberta‐Saskatchewan border, one of the largest Canadian oil reserves.     

Development and Internal Validation of a Predictive Model Including Pulse Oximetry for Hospitalization of Under-Five Children in Bangladesh

Background

The reduction in the deaths of millions of children who die from infectious diseases requires early initiation of treatment and improved access to care available in health facilities. A major challenge is the lack of objective evidence to guide front line health workers in the community to recognize critical illness in children earlier in their course.

Methods

We undertook a prospective observational study of children less than 5 years of age presenting at the outpatient or emergency department of a rural tertiary care hospital between October 2012 and April 2013. Study physicians collected clinical signs and symptoms from the facility records, and with a mobile application performed recordings of oxygen saturation, heart rate and respiratory rate. Facility physicians decided the need for hospital admission without knowledge of the oxygen saturation. Multiple logistic predictive models were tested.

Findings

Twenty-five percent of the 3374 assessed children, with a median (interquartile range) age of 1.02 (0.42–2.24), were admitted to hospital. We were unable to contact 20% of subjects after their visit. A logistic regression model using continuous oxygen saturation, respiratory rate, temperature and age combined with dichotomous signs of chest indrawing, lethargy, irritability and symptoms of cough, diarrhea and fast or difficult breathing predicted admission to hospital with an area under the receiver operating characteristic curve of 0.89 (95% confidence interval -CI: 0.87 to 0.90). At a risk threshold of 25% for admission, the sensitivity was 77% (95% CI: 74% to 80%), specificity was 87% (95% CI: 86% to 88%), positive predictive value was 70% (95% CI: 67% to 73%) and negative predictive value was 91% (95% CI: 90% to 92%).

Conclusion

A model using oxygen saturation, respiratory rate and temperature in combination with readily obtained clinical signs and symptoms predicted the need for hospitalization of critically ill children. External validation of this model in a community setting will be required before adoption into clinical practice.     

Codon bias and gene expression of mitochondrial ND2 gene in chordates

Background: Mitochondrial ND gene, which encodes NADH dehydrogenase, is the first enzyme of the mitochondrial electron transport chain. Leigh syndrome, a neurodegenerative disease caused by mutation in the ND2 gene (T4681C), is associated with bilateral symmetric lesions in basal ganglia and subcortical brain regions. Therefore, it is of interest to analyze mitochondrial DNA to glean information for evolutionary relationship. This study highlights on the analysis of compositional dynamics and selection pressure in shaping the codon usage patterns in the coding sequence of MT-ND2 gene across pisces, aves and mammals by using bioinformatics tools like effective number of codons (ENC), codon adaptation index (CAI), relative synonymous codon usage (RSCU) etc. Results: We observed a low codon usage bias as reflected by high ENC values in MT-ND2 gene among pisces, aves and mammals. The most frequently used codons were ending with A/C at the 3^rd position of codon and the gene was AT rich in all the three classes. The codons TCA, CTA, CGA and TGA were over represented in all three classes. The F1 correspondence showed significant positive correlation with G, T3 and CAI while the F2 axis showed significant negative correlation with A and T but significant positive correlation with G, C, G3, C3, ENC, GC, GC1, GC2 and GC3. Conclusions: The codon usage bias in MTND2 gene is not associated with expression level. Mutation pressure and natural selection affect the codon usage pattern in MT-ND 2 gene.