Apparent diffusion coefficients of normal uterus in premenopausal women with 3 T MRI

AIM

To investigate the apparent diffusion coefficient (ADC) values of the normal uterine cervical zonal structures (cervical epithelium, the junctional zone, and myometrium) during different phases of the menstrual cycle among premenopausal women in different age groups.

MATERIALS AND METHODS

Seventy healthy women, who were divided into three age groups (group A, 24 women in their twenties; group B, 23 women in their thirties; group C, 23 women in their forties), underwent 3 T magnetic resonance imaging (MRI) with T2-weighted and diffusion-weighted imaging (DWI) during the mid-proliferative and the mid-secretory phases.

RESULTS

The ADC values of each cervical zonal structure were significantly different from one another (p < 0.001). The ADC values of the epithelium and junctional zones were both lower during the mid-secretory phase than those during the mid-proliferative phase in each age group (p < 0.05). There were no significant differences in the ADC values of any of the cervical zones among the three age groups for a given phase (p > 0.05).

CONCLUSION

ADC values of normal cervical epithelium and the junctional zone change with different phases of the menstrual cycle, which should be taken into consideration when early cervical disease is detected, when monitoring treatment response, and differentiating early tumour recurrence.

Incremental backpropagation learning networks

How to learn new knowledge without forgetting old knowledge is a key issue in designing an incremental-learning neural network. In this paper, we present a new incremental learning method for pattern recognition, called the "incremental backpropagation learning network", which employs bounded weight modification and structural adaptation learning rules and applies initial knowledge to constrain the learning process. The viability of this approach is demonstrated for classification problems including the iris and the promoter domains.

Seebeck rectification enabled by intrinsic thermoelectrical coupling in magnetic tunneling junctions

An intrinsic thermoelectric coupling effect in the linear response regime of magnetic tunneling junctions (MTJ) is reported. In the dc response, it leads to a nonlinear correction to Ohm's law. Dynamically, it enables a novel Seebeck rectification and second harmonic generation, which apply for a broad frequency range and can be magnetically controlled. A phenomenological model on the footing of the Onsager reciprocal relation and the principle of energy conservation explains very well the experimental results obtained from both dc and frequency-dependent transport measurements performed up to GHz frequencies. Our work refines previous understanding of magnetotransport and microwave rectification in MTJs. It forms a new foundation for utilizing spin caloritronics in high-frequency applications.

Comparison of Tetrahymena pyriformis toxicity based on hydrophobicity, polarity, ionization and reactivity of class-based compounds

A toxicity data set containing the toxicities of 970 hydrophobic, polar and ionizable, nitro substituted and α,β-unsaturated compounds to Tetrahymena pyriformis was classified into different groups based on the structure and substituted functional groups. Polar, ionizable and reactive compounds exhibit greater toxicity as compared with the non-polar hydrophobic compounds. Step-by-step analysis was carried out between the toxicity and descriptors representing hydrophobicity, polarity/polarizability, ionization and reactivity of compounds. Significant relationships were developed between the toxicity and these descriptors for the compounds. The models developed are simple, interpretable and transparent, using a small number of descriptors that may reflect the interactions of chemicals with the biological macromolecules at the target sites. Hydrophobic parameter log P reflects bio-uptake process compounds. Polarity/polarizability descriptor S reflects the interaction of hydrophilic residues of polar chemicals with biological macromolecules. The fractions of ionized (F (i)) and neutral (F (0)) forms calculated from pK (a) reflect the interactions of ionizable compounds with the macromolecules and effect of ionization of ionizable compounds on the bio-uptake process, respectively. A successful single model was developed by using the descriptors log P, S, F (i) and log F (0) for non-polar, polar and ionizable compounds.

Linear and non-linear relationships between soil sorption and hydrophobicity

The relationship between log K (oc) and log P was examined by use of a large dataset. For most of the hydrophobic compounds (e.g. 0.5 < log P < 7.5), the organic carbon content plays a dominant role in soil sorption and the sorption coefficient is linearly related to the octanol/water partition coefficient. For hydrophilic compounds (e.g. log P < 0.5), hydrophobic sorption becomes less significant. The hydrophilic contribution to sorption is equal to, or higher than, the hydrophobic contribution to sorption, resulting in the observed K (oc) values being higher than those predicted from their log P values. For highly hydrophobic compounds (e.g. log P > 7.5), log K (oc) decreases with increasing hydrophobicity because of a lack of chemical availability due to low solubility. A linear solvation energy relationship shows that the sorption potential increases with increasing molecular size by increasing the dispersion interactions between the chemical and soil organic phase. The sorption potential decreases with increase in the basicity of hydrophobic compounds by increasing the H-bonding of chemicals with water. Principal component analysis shows that the octanol/water system is the closest system, but not an ideal surrogate, to describe the soil sorption for hydrophobic compounds as compared with other solvent/water partition systems.

Multiple activities of insect repellents on odorant receptors in mosquitoes

Several lines of evidence suggest that insect repellent molecules reduce mosquito-host contacts by interacting with odorants and odorant receptors (ORs), thereby ultimately affecting olfactory-driven behaviours. We describe the molecular effects of 10 insect repellents and a pyrethroid insecticide with known repellent activity on two highly specific Aedes aegypti (Diptera: Culicidae) ORs, AaOR2 + AaOR7 and AaOR8 + AaOR7, exquisitely sensitive to key mosquito attractants indole and (R)-(-)-1-octen-3-ol, expressed in oocytes of Xenopus (Anura: Pipidae). Our study demonstrates that insect repellents can both inhibit odorant-evoked currents mediated by ORs and independently elicit currents in the absence of odorants. All of the repellents had effects on one or both ORs; most of these compounds were selective inhibitors and showed a high degree of specificity in their capacity to activate the two ORs. These results show that a range of insect repellents belonging to structurally diverse chemical classes modulate the function of mosquito ORs through multiple molecular mechanisms.

Junction temperature measurement of light emitting diode by electroluminescence

Junction temperature (JT) is a key parameter of the performance and lifetime of light emitting diodes (LEDs). In this paper, a mobile instrument system has been developed for the non-contact measurement of JTs of LED under LabVIEW control. The electroluminescence (EL) peak shift of the LED is explored to measure the JT. Commercially available high power blue LEDs are measured. A linear relation between emission peak shift and JT is found. The accuracy of the JT is about 1 °C determined by the precision of the emission peak shift, ±0.03 nm, at 3σ standard deviation for blue LED. Using this system, on-line temperature rise curves of LED lamps are determined.

Overexpression of matrix metalloproteinase 10 is associated with poor survival in patients with early stage of esophageal squamous cell carcinoma

Matrix metallopeptidase 10 (MMP10) is frequently expressed and correlates closely with metastasis and poor prognosis in various human cancers. However, the significance of MMP10 expression in esophageal squamous cell carcinoma (ESCC) and its role in ESCC progression remains unclear. In this report, upregulation of MMP10 mRNA was detected in 39/60 (65.0%) of primary ESCC tissues compared with their paired nontumor esophageal tissues. Tissue microarray (TMA) study found protein overexpression of MMP10 in 188/239 (78.7%) of primary ESCC tissues but not in their corresponding nontumor esophageal tissues, suggesting that overexpression of MMP10 may play important roles in ESCC development and progression. Although the overexpression of MMP10 was not significantly associated with disease-specific survival rate (P= 0.182) for all tested ESCCs, it was significantly associated with poorer disease-specific survival (P= 0.001) in early stage of ESCCs (I-IIA). In addition, multivariate analysis found that MMP10 expression in tumor tissues was evaluated as a potential independent prognostic factor for early stage ESCC patients. These findings suggest that MMP10 plays an important role in ESCC progression in the early stage, and overexpression of MMP10 in tumor tissues could be used as a potential prognostic marker for patients with early clinical stage of ESCC.

Observation of a warped helical spin texture in Bi2Se3 from circular dichroism angle-resolved photoemission spectroscopy

A differential coupling of topological surface states to left- versus right-circularly polarized light is the basis of many optospintronics applications of topological insulators. Here we report direct evidence of circular dichroism from the surface states of Bi(2)Se(3) using laser-based time-of-flight angle-resolved photoemission spectroscopy. By employing a novel sample rotational analysis, we resolve unusual modulations in the circular dichroism photoemission pattern as a function of both energy and momentum, which perfectly mimic the predicted but hitherto unobserved three-dimensional warped spin texture of the surface states. By developing a microscopic theory of photoemission from topological surface states, we show that this correlation is a natural consequence of spin-orbit coupling. These results suggest that our technique may be a powerful probe of the spin texture of spin-orbit coupled materials in general.

Psychological distress in people with disfigurement from facial palsy

AIMS

Psychological distress is well documented in people with facial disfigurement. However, the prevalence of psychological distress in patients with facial palsy has not been studied. This study aims to establish the prevalence of psychological distress and the extent of anxiety and depression in a sample of facial palsy patients from the Northwest of England.

METHOD

A total of 103 participants with facial palsy completed a questionnaire pack comprising the Illness Perception Questionnaire-Revised (IPQ-R), a demographic questionnaire, and the Hospital Anxiety and Depression Scale (HADS). The severity of participants' facial palsy was measured by the House-Brackmann scale.

RESULTS

In all, 32.7 and 31.3% of the sample had significant levels of anxiety and depression, respectively. The mean age of participants was 59, and 35.9% had grade 6 facial palsy. Significant associations were found between participants' perception of consequences, duration, timeline, and the level of distress. No significant associations were found between clinical severity of facial palsy and levels of distress. Females had significantly higher levels of anxiety compared with males.

CONCLUSIONS

There was a significant level of distress in this study group. The levels of psychological distress were higher than the levels found in other outpatient attenders. There were significant associations between participants' illness perceptions and their level of distress.

The use of lithotomy by missionary surgeons in nineteenth-century China

Modern medicine in China owes its origins to Anglo-American medical missionaries who introduced Western medicine into China in the early nineteenth century. In 1835 the first medical missionary to China, the Reverend Dr Peter Parker, founded the Canton Ophthalmic Hospital where he pioneered lithotomy and other surgical operations for Chinese patients. This paper chronicles the subsequent development of surgery for bladder stones at that institution by Dr Parker, Dr John Kerr and their successors. Modifications of technique and improvisations by these dedicated practitioners under less-than-optimal conditions and in an unfamiliar population, provide a unique and interesting insight into medicine of the time as practiced in China.

Trends and Developments in Bioinformatics in 2010: Prospects and Perspectives

To survey major developments and trends in the field of Bioinformatics in 2010 and their relationships to those of previous years, with emphasis on long-term trends, on best practices, on quality of the science of informatics, and on quality of science as a function of informatics.

A critical review of articles in the literature of Bioinformatics over the past year.

Our main results suggest that Bioinformatics continues to be a major catalyst for progress in Biology and Translational Medicine, as a consequence of new assaying technologies, most predominantly Next Generation Sequencing, which are changing the landscape of modern biological and medical research. These assays critically depend on bioinformatics and have led to quick growth of corresponding informatics methods development. Clinical-grade molecular signatures are proliferating at a rapid rate. However, a highly publicized incident at a prominent university showed that deficiencies in informatics methods can lead to catastrophic consequences for important scientific projects. Developing evidence-driven protocols and best practices is greatly needed given how serious are the implications for the quality of translational and basic science.

Several exciting new methods have appeared over the past 18 months, that open new roads for progress in bioinformatics methods and their impact in biomedicine. At the same time, the range of open problems of great significance is extensive, ensuring the vitality of the field for many years to come.