Coupled ferroelectric polarization and magnetization in spinel FeCr2S4

One of the core issues for multiferroicity is the strongly coupled ferroelectric polarization and magnetization, while so far most multiferroics have antiferromagnetic order with nearly zero magnetization. Magnetic spinel compounds with ferrimagnetic order may be alternative candidates offering large magnetization when ferroelectricity can be activated simultaneously. In this work, we investigate the ferroelectricity and magnetism of spinel FeCr₂S₄ in which the Fe²⁺ sublattice and Cr³⁺ sublattice are coupled in antiparallel alignment. Well defined ferroelectric transitions below the Fe²⁺ orbital ordering termperature T_oo = 8.5 K are demonstrated. The ferroelectric polarization has two components. One component arises mainly from the noncollinear conical spin order associated with the spin-orbit coupling, which is thus magnetic field sensitive. The other is probably attributed to the Jahn-Teller distortion induced lattice symmetry breaking, occuring below the orbital ordering of Fe²⁺. Furthermore, the coupled ferroelectric polarization and magnetization in response to magnetic field are observed. The present work suggests that spinel FeCr₂S₄ is a multiferroic offering both ferroelectricity and ferrimagnetism with large net magnetization.

Bacillus sp. LT3 improves the survival of gnotobiotic brine shrimp (Artemia franciscana) larvae challenged with Vibrio campbellii by enhancing the innate immune response and by decreasing the activity of shrimp-associated vibrios

Bacteria belonging to the genus Bacillus are amongst the most intensively studied group of bacteria for use as probiotics in aquaculture. However, the exact mechanism of action of these bacteria is often not well described, and the microbiota that are naturally present in cultures of test organisms often compromise the interpretation of the results. The present study aimed to evaluate the putative probiotic effect of Bacillus sp. LT3 in a model system with gnotobiotic brine shrimp Artemia franciscana larvae. The strain significantly increased the survival of brine shrimp larvae challenged with Vibrio campbellii when administered 6h before the challenge. Under these conditions, LT3 was able to colonize the brine shrimp gastrointestinal tract and to decrease the in vivo pathogen activity as indicated by the bioluminescence of the V. campbellii associated with brine shrimp larvae. In order to investigate the effect of the Bacillus strain on the innate immune system of the brine shrimp larvae, prophenoloxidase and transglutaminase mRNA levels were monitored, while heat shock protein 70 mRNA levels were measured as an indicator of physiological stress. Interestingly, 12h after challenge, the prophenoloxidase mRNA level in the larvae pre-treated with LT3 and challenged with V. campbellii was approximately 8-fold higher than in the other treatments. Further, a decreased mRNA level of transglutaminase gene and heat shock protein 70 gene suggested that pretreatment with LT3 results in less stress and tissue damage in the brine shrimp larvae upon V. campbellii challenge. These results indicated that Bacillus sp. LT3 could improve the survival of brine shrimp larvae when challenged with pathogenic V. campbellii, both by decreasing the in vivo activity of the pathogen and by priming the innate immune response through activating the prophenoloxidase system.

Narrow tuning of an odorant receptor to plant volatiles in Spodoptera exigua (Hübner)

Olfaction plays an important role in insects in recognizing volatile compounds, which are used to find food and mates, as well as avoid danger, predators and pathogens. The key players in the detection of volatile compounds are olfactory receptor (OR) proteins, which are located within the dendritic membrane of sensory neurons and extend into the lymph of sensilla on insect antennae. In the present study, we identify an OR gene, named SexiOR3, which is expressed in adult antenna in both sexes, but with female bias, in the beet armyworm moth Spodoptera exigua. Further in situ hybridization analysis revealed that SexiOR3 was mainly located in short trichoid sensilla. In in vitro heterologous expression experiments, SexiOR3 was narrowly tuned to E-β-farnesene and several compounds of related structure, among 62 different compounds tested in this study. Furthermore, SexiOR3 responds to E-β-farnesene at a low concentration of 10(-9)  M, comparable to that of pheromone receptors (PRs) responding to the pheromones. This is a very interesting finding for a general OR, indicating that high specificity is a feature of at least one general OR and not only the PRs. The results suggest that the OR3 gene may play an important role in the moth olfactory system, and underpins important insect behaviour.

Visualizing cerebral veins in fetal brain using susceptibility-weighted MRI

AIM

To explore the feasibility of two-dimensional (2D) susceptibility-weighted imaging (SWI) in the visualization of cerebral veins in the foetal brain.

MATERIALS AND METHODS

Forty-two pregnant healthy women (gestational age: 19-37 weeks, mean: 28.5 ± 7.1 weeks) underwent SWI examination using a 1.5 T MRI system. Two neurologists independently analysed all magnetic resonance imaging (MRI) studies. The relationship between the veins detected and the gestational age was investigated. The prominence of veins was assessed using a categorical score.

RESULTS

In total, 167 veins were detected by SWI in 29 subjects with a symmetric hemisphere distribution (p > 0.05). An additional vein was detected by SWI biweekly from 24 weeks of gestation. Most veins of Galen and internal cerebral veins on SWI images were prominent, whereas others were faint or moderate.

CONCLUSION

SWI appears to be a feasible method of detecting cerebral veins in the foetal brain.

Immigrants' perceptions of the quality of their cancer care: an Australian comparative study, identifying potentially modifiable factors

BACKGROUND

Recent data show a falling cancer mortality in the general population without a similar shift in immigrant outcomes, leading to a greater cancer burden and mortality for immigrants. Our aims were to compare perceived patterns of care in immigrants and native-born cancer patients.

PATIENTS AND METHODS

This was a hospital-based sample of first-generation immigrants and Australian-born Anglo patients in the first year following diagnosis. It was restricted to Chinese, Arabic, or Greek speakers. Eligible participants, recruited via 16 oncology clinics, were over 18, with cancer (any type or stage), and having commenced treatment at least 1 month previously. Five hundred and seventy-one CALD patients (comprising 145 Arabic, 248 Chinese, and 178 Greek) and a control group of 274 Anglo-Australian patients participated.

RESULTS

Immigrants had difficulty communicating with the doctor (73% versus 29%) and understanding the health system (38% versus 10%). Differences were found in 'difficulty knowing who to see' (P = 0.0002), 'length of time to confirm diagnosis' (P = 0.04), wanting more choice about a specialist and hospital (P < 0.0001); being offered the opportunity to see a counselor (P < 0.0001); and actually seeing one (P < 0.0001). There were no significant self-reported differences regarding how cancer was detected, time to see a health professional, or type first seen; however, immigrants reported difficulty knowing who to see. Previous studies showed differences in patterns of care according to socioeconomic status (SES) and educational level. Despite adjusting for age, sex, education, marital status, SES, time since diagnosis, and type of cancer, we did not find significant differences. Instead, we found that understanding of the health system and confidence understanding English were important factors.

CONCLUSIONS

This study confirmed that immigrants with cancer perceive an inferior quality of cancer care. We highlight potentially modifiable factors including assistance in navigating the health system, translated information, and cultural competency training for health professionals.

Experimental observation of ferrielectricity in multiferroic DyMn2O5

One of the major breakthroughs associated with multiferroicity in recent years is the discovery of ferroelectricity generated by specific magnetic structures in some magnetic insulating oxides such as rare-earth manganites RMnO3 and RMn2O5. An unresolved issue is the small electric polarization. Relatively large electric polarization and strong magnetoelectric coupling have been found in those manganites of double magnetic ions: magnetic rare-earth R ion and Mn ion, due to the strong R-Mn (4f-3d) interactions. DyMn2O5 is a representative example. We unveil in this work the ferrielectric nature of DyMn2O5, in which the two ferroelectric sublattices with opposite electric polarizations constitute the ferrielectric state. One sublattice has its polarization generated by the symmetric exchange striction from the Mn-Mn interactions, while the polarization of the other sublattice is attributed to the symmetric exchange striction from the Dy-Mn interactions. We present detailed measurements on the electric polarization as a function of temperature, magnetic field, and measuring paths. The present experiments may be helpful for clarifying the puzzling issues on the multiferroicity in DyMn2O5 and other RMn2O5 multiferroics.

Expression of SNMP1 and SNMP2 genes in antennal sensilla of Spodoptera exigua (Hübner)

Sensory neuron membrane proteins (SNMPs) are olfactory-specific, two-transmembrane proteins. Previous publications reported that SNMP1 is expressed on the dendrite membrane of pheromone-sensitive neurons in Heliothis virescens and is an essential cofactor for pheromone detection in Drosophila. In this study, we cloned two SNMP genes (GenBank accession nos. JX469106 and JX469107) from the antenna of the beet armyworm moth Spodoptera exigua (Lepidoptera: Hübner). These SNMP genes are classified into two highly conserved subclades, indicating their importance in physiological activity of lepidopteran insects. SexiSNMP1 is antenna-specific in male and female adults, while SexiSNMP2 is antenna-abundant but also expressed in other chemosensory tissues, particularly proboscises and maxillary palps of adults both sexes. In situ hybridization revealed that both SNMPs are broadly expressed in long and short trichoid and basiconic sensilla. We infer that SNMP1 and SNMP2 act in the detection of the sex pheromone and general odorants.

Effects of a protease inhibitor protein from Xenorhabdus bovienii on physiology of pea aphid (Acyrthosiphon pisum)

The effects of a protease inhibitor protein from Xenorhabdus bovienii strain xbi1 (Xbpi-1) on biochemistry and physiology of pea aphid (Acyrthosiphon pisum) were studied, and the effects of Xbpi-1 on the activities of aphid aminopeptidase and the concentrations of carbohydrates, free amino acids and lipids in A. pisum were determined. The results showed that the activity of aminopeptidase was reduced 18.30% by Xbpi-1 in vitro assays. In addition, the total sugar, glycogen, and lipid concentrations per aphid fed on an artificial diet with Xbpi-1 were reduced by 39.41%, 24.61% and 26.25%, respectively, compared to the controls. The total free amino acids in the aphids on the diet with Xbpi-1 was significantly decreased by 20.78% compared to the control. The mortalities of A. pisum were significantly higher when the concentrations of Xbpi-1 were 400 and 800 μg/ml in the artificial diet. The results from this study indicated that Xbpi-1 had adverse effects on the physiology and biochemistry of A. pisum.

ReSeqTools: an integrated toolkit for large-scale next-generation sequencing based resequencing analysis

Large-scale next-generation sequencing (NGS)-based resequencing detects sequence variations, constructs evolutionary histories, and identifies phenotype-related genotypes. However, NGS-based resequencing studies generate extraordinarily large amounts of data, making computations difficult. Effective use and analysis of these data for NGS-based resequencing studies remains a difficult task for individual researchers. Here, we introduce ReSeqTools, a full-featured toolkit for NGS (Illumina sequencing)-based resequencing analysis, which processes raw data, interprets mapping results, and identifies and annotates sequence variations. ReSeqTools provides abundant scalable functions for routine resequencing analysis in different modules to facilitate customization of the analysis pipeline. ReSeqTools is designed to use compressed data files as input or output to save storage space and facilitates faster and more computationally efficient large-scale resequencing studies in a user-friendly manner. It offers abundant practical functions and generates useful statistics during the analysis pipeline, which significantly simplifies resequencing analysis. Its integrated algorithms and abundant sub-functions provide a solid foundation for special demands in resequencing projects. Users can combine these functions to construct their own pipelines for other purposes.

Expression and clinical significance of SHP2 in gastric cancer

OBJECTIVES

To investigate the expression and clinical significance of the protein tyrosine phosphatase, nonreceptor type 11 (PTPN11 or SHP2) gene, which encodes Src homology 2 domain-containing phosphatase (SHP-2) in gastric cancer.

METHODS

SHP2 expression was detected by immunohistochemical staining and real-time quantitative reverse transcription-polymerase chain reaction in tissue samples of normal gastric mucosa and different grades of gastric cancer. Correlation between SHP2 expression and standard clinico pathological parameters was analysed.

RESULTS

Immunohistochemical staining revealed significantly higher rates of SHP2 expression in gastric cancer tissues (72.5%) versus normal gastric mucosa (21.9%). SHP-2 mRNA levels were also significantly higher in gastric cancer tissues versus normal gastric mucosa. SHP2 expression correlated significantly with tumour differentiation, clinical classification and lymph node metastases, but was independent of sex and age.

CONCLUSIONS

SHP-2 is upregulated in gastric cancer and may be related to the development of gastric cancer. SHP-2 may be a potential prognostic marker of, or a therapeutic target for, gastric cancer.

Identification and functional characterization of sex pheromone receptors in beet armyworm Spodoptera exigua (Hübner)

In moths, males can detect a distinct blend of several pheromone components by specialized olfactory receptor neurons (ORNs) on the antennae. Four candidate pheromone receptors (PR) with seven transmembrane domains were identified by homology cloning from the antennae of Spodoptera exigua (Sexi). Phylogenetic analyses reveal that all four odorant receptors (OR) belong to pheromone receptor subtypes. Expression patterns revealed that PRs were male-specific in the antenna except for SexiOR11, which was female antenna-biased. Functional analyses of these PRs were conducted using heterologous expression in Xenopus oocytes. SexiOR13 and SexiOR16 were all broadly activated by multiple pheromone components. SexiOR13 responded robustly to the critical pheromone component, Z9, E12-14:OAc and the minor pheromone component, Z9-14:OAc at a concentration of 10(-4) M. Dose-response studies indicate that SexiOR13 was approximately 4 times more sensitive to Z9,E12-14:OAc (EC50 = 3.158 × 10(-6) M) compared to Z9-14:OAc (EC50 = 1.203 × 10(-5) M). While, SexiOR16 responded robustly to the secondary pheromone component Z9-14:OH with high sensitivity (EC50 = 9.690 × 10(-7) M). However, similar tests of the five pheromones with SexiOR6 and SexiOR11 failed to elicit any response. These results provide basic knowledge to further advance research on the molecular mechanisms of pheromone reception.

Unilateral deep brain stimulation of the right globus pallidus internus in patients with Tourette's syndrome: two cases with outcomes after 1 year and a brief review of the literature

Tourette's syndrome is a complex neuropsychiatric disorder, characterized by tics. Bilateral globus pallidus internus (GPi) deep brain stimulation (DBS) has been considered to be an effective treatment for refractory Tourette's syndrome. Postoperative outcomes are described after 12 months' follow-up in a 41-year-old male patient and a 22-year-old male patient with Tourette's syndrome, both of whom underwent unilateral electrode implantations into the right GPi for DBS. These patients were diagnosed with Tourette's syndrome in childhood and, despite long-term therapy with a range of antipsychotic medications, continued to experience disabling tics in adulthood. Improvements in tic severity of 58.5% and 53.1% were observed at 12 months in the older and younger patient, respectively; improvements were determined by the Yale Global Tic Severity Scale. Both patients also experienced reductions in tic frequency and reported improvements in their health-related quality of life. Improvements in tics were similar to previous reports involving patients who underwent bilateral GPi DBS. These cases suggest that unilateral DBS of the right GPi is effective and might be a viable surgical choice for some patients with Tourette's syndrome.

Obstetric outcome of ethnic Turkish women in London: a retrospective case-control study

There is concern that the maternal mortality in ethnic minority women is significantly greater than that of Caucasian British women. The objective of this study was to compare the demographic and obstetric outcomes between these two groups. Data were collected retrospectively over a 2-year period from 148 index and 148 control cases. The study group had statistically similar maternal age, labour duration, blood loss and mode of delivery compared with Caucasian British women (p > 0.05). A total of 68% of Turkish women spoke little or no English; were more likely to be non-smokers and also more likely to be married to unemployed spouses (p = 0.0001). This is the first study comparing obstetric outcomes of immigrant Turkish women with their Caucasian British counterparts. There was no significant difference in maternal or fetal outcomes, which could be attributed to the 'healthy migrant' theory, coupled with increased vigilance in ethnic minority pregnancies.

Effector biology of plant-associated organisms: concepts and perspectives

Every plant is closely associated with a variety of living organisms. Therefore, deciphering how plants interact with mutualistic and parasitic organisms is essential for a comprehensive understanding of the biology of plants. The field of plant-biotic interactions has recently coalesced around an integrated model. Major classes of molecular players both from plants and their associated organisms have been revealed. These include cell surface and intracellular immune receptors of plants as well as apoplastic and host-cell-translocated (cytoplasmic) effectors of the invading organism. This article focuses on effectors, molecules secreted by plant-associated organisms that alter plant processes. Effectors have emerged as a central class of molecules in our integrated view of plant-microbe interactions. Their study has significantly contributed to advancing our knowledge of plant hormones, plant development, plant receptors, and epigenetics. Many pathogen effectors are extraordinary examples of biological innovation; they include some of the most remarkable proteins known to function inside plant cells. Here, we review some of the key concepts that have emerged from the study of the effectors of plant-associated organisms. In particular, we focus on how effectors function in plant tissues and discuss future perspectives in the field of effector biology.

Regulation of ATG6/Beclin-1 homologs by abiotic stresses and hormones in rice (Oryza sativa L.)

Autophagy, a complex and conserved mechanism, serving as a defense response in all eukaryotic organisms, is regulated by several proteins, among which ATG proteins are the most important due to their involvement in autophagosome formation. ATG6/Beclin-1 proteins, reported to be essential for autophagosome formation and assigned as a conserved domain, were subjected to database searches. We found three homologs in the rice (Oryza sativa) genome. A phylogeny tree was constructed to establish their across species relationship, which divided them into three distinct groups; two for plants, i.e., monocots and dicots, and one for animals. Evolutionary study of this family by critical amino acid conservation analysis revealed significant functional divergence. The finding of important stress-related cis-acting elements in the promoter region of rice ATG6 genes demonstrated their involvement in abiotic stress responses. Furthermore, expression profiling of rice ATG6 genes based on microarray data, as well as by semi-quantitative RT-PCR showed differential expression when subjected to different stresses suggesting the involvement of OsATG6 genes in abiotic stresses (heat, cold and drought) and hormone (abscisic acid) responses. Analysis of co-expressed genes showed that most of them annotated to DNA repair pathways and proteolysis, etc. Collectively, these results suggest the involvement of OsATG6 genes in different stresses, and provide a basis for further functional studies to investigate the biological mechanism of action of these genes under abiotic stresses.

Detection of hydrazine, methylhydrazine, and isoniazid by capillary electrophoresis with a palladium-modified microdisk array electrode

A palladium particle-modified carbon fiber microdisk array electrode was designed and employed in capillary electrophoresis for the simultaneous detection of hydrazine, methylhydrazine, and isoniazid. The Pd-modified microdisk electrode had high catalytic ability for hydrazines and exhibited good reproducibility and stability. The response for hydrazine was linear over 3 orders of magnitude with a correlation coefficient of 0.993. The detection limits for hydrazine, methylhydrazine, and isoniazid were 1.2, 2.1, and 6.2 pg, respectively.