Understanding the electronic and phonon transport properties of a thermoelectric material BiCuSeO: a first-principles study

Using the first-principles pseudopotential method and Boltzmann transport theory, we give a comprehensive understanding of the electronic and phonon transport properties of a thermoelectric material BiCuSeO.

Low Serum Levels of 25-Hydroxyvitamin D Are Associated with Stroke Recurrence and Poor Functional Outcomes in Patients with Ischemic Stroke

OBJECTIVE

To evaluate the association between serum 25(OH) D levels and functional outcome and stroke recurrence events in a 6-month follow-up study in a cohort of patients with an acute ischemic stroke (AIS).

METHODS

From March 2014 to August 2015, consecutive first-ever AIS patients admitted to the Department of Emergency of our hospital were identified. Serum 25(OH) D levels were measured at admission. Functional outcome was evaluated at 6-month using the modified Rankin scale (m-Rankin). We used logistic regression models to assess the relationship between 25(OH) levels and risk of recurrent stroke or functional outcome.

RESULTS

We recorded 277 stroke patients. There were significantly negative correlation between levels of 25(OH) D and NHISS (P<0.001), and the infarct volume (P< 0.001). Thirty-one patients (11.9%) had a stroke recurrence, while 82 patients (29.6) were with poor functional outcomes. In multivariate logistic regression analyses, serum 25(OH) D level was an independent marker of poor functional outcome and stroke recurrence [odds ratio (OR) 2.55 (1.38-3.96) and 3.03(1.65-4.12), respectively, P<0.001 for both, adjusted for NHISS, other predictors and vascular risk factors] in patients with AIS.

CONCLUSION

Our results demonstrate that low 25(OH) D levels are associated with stroke recurrence and support the hypothesis that 25(OH) D may serve as a biomarker of poor functional outcome after stroke.

MicroRNA-155 is a biomarker of T-cell activation and immune dysfunction in HIV-1-infected patients

OBJECTIVES

MicroRNA-155 (miR-155) regulates T-cell differentiation and activation. It has also been associated with HIV infection. However, it remains unclear whether miR-155 is related to the T-cell response in HIV-infected individuals (e.g. T-cell activation and exhaustion).

METHODS

We performed a cross-sectional study involving 121 HIV-1-infected patients on highly active antiretroviral therapy (HAART) and 43 HAART-naïve patients. MiR-155 levels in the peripheral blood were determined by quantitative reverse transcription-polymerase chain reaction (PCR). T-cell immune activation, exhaustion, and homeostasis were measured by determining the expression of CD38, programmed death 1 (PD-1) and CD127 via flow cytometry.

RESULTS

The levels of miR-155 in total peripheral blood mononuclear cells, CD4 T cells and CD8 T cells from HIV-1-infected patients were increased (P < 0.01). Nonresponders and HAART-naïve patients also exhibited a higher percentage of CD8⁺ CD38⁺ T cells and a lower percentage of CD4⁺ CD127⁺ and CD8⁺ CD127⁺ T cells (P < 0.05). We also found higher levels of PD-1 expression on the CD4⁺ and CD8⁺ T cells of HIV-1-infected patients (P < 0.05).

CONCLUSIONS

Our findings suggest that miR-155 levels in the peripheral blood of HIV-1-infected patients are increased and associated with T-cell activation. Therefore, miR-155 is a potential biomarker of the immune response following HIV-1 infection.

Precision Measurement of the Boron to Carbon Flux Ratio in Cosmic Rays from 1.9 GV to 2.6 TV with the Alpha Magnetic Spectrometer on the International Space Station

Knowledge of the rigidity dependence of the boron to carbon flux ratio (B/C) is important in understanding the propagation of cosmic rays. The precise measurement of the B/C ratio from 1.9 GV to 2.6 TV, based on 2.3 million boron and 8.3 million carbon nuclei collected by AMS during the first 5 years of operation, is presented. The detailed variation with rigidity of the B/C spectral index is reported for the first time. The B/C ratio does not show any significant structures in contrast to many cosmic ray models that require such structures at high rigidities. Remarkably, above 65 GV, the B/C ratio is well described by a single power law R^{Δ} with index Δ=-0.333±0.014(fit)±0.005(syst), in good agreement with the Kolmogorov theory of turbulence which predicts Δ=-1/3 asymptotically.

[Clinical and pathological characteristics of vocal fold leukoplakia and influential factors of recurrence and malignancy]

Objective:To investigate the clinical and pathological characteristics of vocal fold leukoplakia and influential factors of recurrence and malignancy. Method:The study included 555 cases of vocal fold leukoplakia. All patients received surgical treatment. The relationship between the clinical and pathological features, and influential factors of recurrence and malignancy were analyzed. Result:The pathological types included squamous epithelial simple hyperplasia in 58.0%, mild hyperplasia in 15.5%, moderate hyperplasia in 10.1%, severe hyperplasia and carcinoma in situ in 8.1%, infiltrative carcinoma in 8.3%. The different pathological types varied among different ages significantly(P<0.01). The tobacco and alcohol abuse had no relationship with pathological types(P>0.05). The more severe the pathology were, the more decreasing of the mucosal waves would be(P<0.01). The pathologic severity had an apparent correlation with p53 positivity and the level of p53 and Ki67 positivity. The p53 positive proportion may increase with the increasing pathological severity(P<0.01), so were the p53 and Ki67 positive levels(P<0.01).Among 232 cases of postoperation follow-ups, 83 cases(35.8%) relapsed while 8 cases(3.4%) malignancy. Bilateral lesions had a higher rate of relapse and malignancy than unilateral lesions(95%CIOR 0.378 ［0.197-0.723］，P<0.01). The relapse and malignancy had a relationship with the pathologic severity. The incidence of disease recurrence and malignancy were positively correlated with pathological severity(P<0.05). p16 positive patients relapsed for more times(P<0.01) and with an uprising tendency of relapse and malignancy（P>0.05）. Conclusion:Pathological types of vocal fold leukoplakia are different. The older men, decreasing of mucosal wave of vocal folds and bilateral lesions were very important factors to predict disease severity. p53 and Ki67 positive rating and pathological severity were positively correlated. The bilateral lesions, pathological severity and p16 positivity had a tendency to increasing relapse and malignancy.

[Reliability and validity of Parkinson's disease sleep scale-Chinese version in the south west of China]

Objective: To evaluate the reliability and validity of Parkinson's disease sleep scale-Chinese version (CPDSS) through a study of a large PD population in southwest China, and to explore the prevalence and characteristics of sleep disorders in Parkinson's disease (PD) patients from southwest China. Methods: A total of 544 PD patients and 220 control subjects were enrolled in our study. Demographic data, CPDSS, ESS, PDQ39, HAMD and H-Y stage were assessed in all subjects. Statistical description, Cronbach's alpha coefficient, intra-class correlation coefficient (ICC), Spearman rank correlation coefficient and Mann-Whitney U test were used for statistical analyses. Result: The Cronbach's alpha coefficient for CPDSS was 0.79, ICC of the total scale was 0.94 and ICC of each item ranged from 0.73 to 0.97. The factor analysis yielded a five-factor solution, which explained 63.4% of the total variance. Total and each item scores of CPDSS in PD patients were lower than those in healthy controls. 69.3% of PD patients had sleep disorder, while prevalence in the control group was only 29.6%. Negative correlation was found between CPDSS and ESS. Daytime sleepiness was the most common factor (35.9%) leading to sleep disorders. The sleep disorders of PD patients in Southwest China were significantly related with the course of disease, the severity of disease, the quality of life, depression, cognitive level and motor symptoms. Conclusion: CPDSS has good feasibility, reliability and validity in PD population from southwest China. CPDSS is considered as an effective tool for the assessment of sleep disorder in PD patients.

Systematic Quality Control Analysis of LINCS Data

The Library of Integrated Cellular Signatures (LINCS) project provides comprehensive transcriptome profiling of human cell lines before and after chemical and genetic perturbations. Its L1000 platform utilizes 978 landmark genes to infer the transcript levels of 14,292 genes computationally. Here we conducted the L1000 data quality control analysis by using MCF7, PC3, and A375 cell lines as representative examples. Before perturbations, a promising 80% correlation in transcriptome was observed between L1000- and Affymetrix HU133A-platforms. After library-based shRNA perturbations, a moderate 30% of differentially expressed genes overlapped between any two selected controls viral vectors using the L1000 platform. The mitogen-activated protein kinase, vascular endothelial growth factor, and T-cell receptor pathways were identified as the most significantly shared pathways between chemical and genetic perturbations in cancer cells. In conclusion, L1000 platform is reliable in assessing transcriptome before perturbation. Its response to perturbagens needs to be interpreted with caution. A quality control analysis pipeline of L1000 is recommended before addressing biological questions.

Synergism between RIZ1 gene therapy and paclitaxel in SiHa cervical cancer cells

RIZ1 is a tumor suppressor gene. The purpose of the present study was to investigate the inhibitory effect of RIZ1 gene therapy on the growth of SiHa cervical cancer cells and its synergism with paclitaxel. The expression levels of RIZ1 were examined by real-time PCR and western blotting before and after transfection of RIZ1. The effects of paclitaxel or pcDNA3.1(+)-RIZ1 alone or in combination, on the proliferation of SiHa cells were evaluated by MTT method. The inhibitory effect on the proliferation of SiHa cells was more significant in the pcDNA3.1(+)-RIZ1 combined with paclitaxel group than in the pcDNA3.1(+)-RIZ1 or paclitaxel groups (P<0.05). The expression level of RIZ1 in SiHa cells increased after treatment with paclitaxel, which indicated a synergism between them. RIZ1 gene therapy combined with paclitaxel showed stronger cell inhibition than paclitaxel alone, which indicated a synergism between them.

Antiproton Flux, Antiproton-to-Proton Flux Ratio, and Properties of Elementary Particle Fluxes in Primary Cosmic Rays Measured with the Alpha Magnetic Spectrometer on the International Space Station

A precision measurement by AMS of the antiproton flux and the antiproton-to-proton flux ratio in primary cosmic rays in the absolute rigidity range from 1 to 450 GV is presented based on 3.49×10^{5} antiproton events and 2.42×10^{9} proton events. The fluxes and flux ratios of charged elementary particles in cosmic rays are also presented. In the absolute rigidity range ∼60 to ∼500  GV, the antiproton p[over ¯], proton p, and positron e^{+} fluxes are found to have nearly identical rigidity dependence and the electron e^{-} flux exhibits a different rigidity dependence. Below 60 GV, the (p[over ¯]/p), (p[over ¯]/e^{+}), and (p/e^{+}) flux ratios each reaches a maximum. From ∼60 to ∼500  GV, the (p[over ¯]/p), (p[over ¯]/e^{+}), and (p/e^{+}) flux ratios show no rigidity dependence. These are new observations of the properties of elementary particles in the cosmos.

Migration of Highly Educated Asians and Global Dynamics

The migration of Asians trained in technical fields is the most important component of the total global migration of scientific, technical and professional workers from developing to developed countries (primarily Australia, Canada and the United States). Though this phenomenon shares common characteristics with the larger international migration of all labor, it is unique in that migration from Asia to the industrialized countries favors the highly educated, and the debate over brain drain remains complex and inconclusive. The far-reaching effects of the movement of Asian high level manpower (HLM) are discussed in light of: 1) the global articulation of higher education; 2) the link to unequal development on a global scale; and 3) the contribution to economic development of the reverse flow of HLM to less developed countries.

Inter-collicular suppression compresses all types of rate-amplitude functions of inferior collicular neurons in mice

The two inferior colliculi (IC) are paired structures in the midbrain that are connected to each other by a bundle of commissural fibers. The fibers play an important role in coordinating sound signal processing between the two inferior colliculi. This study examined inter-collicular suppression on sound signal processing in amplitude domain of mice by measuring the rate-amplitude functions (RAFs) of neurons in one IC during the electrical stimulation of the opposite IC. Three types (monotonic, saturated and non-monotonic) RAFs of collicular neurons were measured before and during inter-collicular suppression. Inter-collicular suppression significantly increased the slope, decreased the dynamic range and narrowed down the responsive amplitude of all RAFs to high amplitude level but did not change the type of most (36/43, 84 %) RAFs. As a result, all types of RAFs were compressed at a greater degree at low than at high sound amplitude during inter-collicular suppression. These data indicate that inter-collicular suppression improve sound processing in the high amplitude domain.

[Revised endoscopic sinus surgery combined middle turbinectomy in the treatment of refractory rhinosinusitis]

Objective:To investigate the comprehensive curativeeffect of refractory rhinosinusitis by endoscopic sinus surgery and middle turbinate resection.Method:A retrospective analysis with 178 cases of refractory rhinosinusitis.According to the operation methods, these patients were divided into two groups, observation group and control group, with 89 patients each. The observationgroup received revision endoscopic sinus surgery combined with middle turbinectomy and the control with traditional surgery. Followup to observe the curative effect and recurrence rate between the two groups. Result:Follow-up after 6 months, total effective rate of observation group was 88.76% and the effective rate of control group was 68.54%.The total effective rate of observation group is higher than the control group, and non efficiency rate is lower than that of the control group; besides that the incidence of complications and the recurrence rate of the observation group was lower than the control group. Conclusion:It can effectively prevent the recurrence of sinusitis by the revised operation of nasal endoscopic frontal sinus combined with middle turbinate partial or complete removal and fully treatment measures of peri operation period, that is to say it can improve the therapeutic effect of refractory sinusitis witch worthing the clinical popularization and application.

Mosquito salivary allergen Aed a 3: cloning, comprehensive molecular analysis, and clinical evaluation

BACKGROUND

Allergic reactions to mosquito bites are an increasing clinical concern. Due to the lack of availability of mosquito salivary allergens, they are underdiagnosed. Here, we reported a newly cloned mosquito Aedes (Ae.) aegypti salivary allergen.

METHODS

A cDNA encoding a 30-kDa Ae. aegypti salivary protein, designated Aed a 3, was isolated from an expression library. The full-length cDNA was cloned into a baculovirus expression vector, and recombinant Aed a 3 (rAed a 3) was expressed, purified, and characterized. Skin prick tests with purified rAed a 3 and Ae. aegypti bite tests were performed in 43 volunteers. Serum rAed a 3-specific IgE levels were measured in 28 volunteers.

RESULTS

The primary nucleotide sequence, deduced amino acid sequence, and IgE-binding sites of Aed a 3 were identified. rAed a 3-selected antibodies recognized a 30-kDa Ae. aegypti saliva protein. rAed a 3 bound IgE in mosquito-allergic volunteers and the binding could be inhibited by the addition of natural mosquito extract dose dependently. Immediate skin test reactions to rAed a 3 correlated significantly with mosquito bite-induced reactions. Of the bite test-positive volunteers, 32% had a positive rAed a 3 skin test and 46% had specific IgE. No bite test-negative volunteers reacted to rAed a 3 in either the skin tests or the IgE assays, confirming the specificity of the assay.

CONCLUSIONS

Aed a 3 that corresponds to the Aegyptin protein is a major mosquito salivary allergen. Its recombinant form has biological activity and is suitable for use in skin tests and specific IgE assays in mosquito-allergic individuals.

Protective effect of ferulic acid against 2,2'-azobis(2-amidinopropane) dihydrochloride-induced oxidative stress in PC12 cells

Oxidative stress is closely related to the pathogenesis of neurodegenerative disorders such as Parkinson's disease and Alzheimer's disease. However, the underlying antioxidant mechanisms of ferulic acid (FA) aganist oxidantive stress are poorly understood. We evaluated the potential protective effects of FA against 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH)-induced damage in PC12 cells. Our results indicated that pretreatment with FA prior to AAPH exposure significantly increased PC12 cell survival, and also increased catalase and superoxide dismutase activity. Furthermore, FA treatment reduced cellular lactate dehydrogenase release and malondialdehyde levels. It attenuated AAPH-induced apoptosis in PC12 cells, as determined by flow cytometric detection of annexin V. Reductions in mitochondrial membrane potential and accumulation of intracellular Ca2+ were also inhibited by FA treatment. These findings suggested that FA protected PC12 cells against AAPH-induced oxidative stress, and may be a neuroprotective agent.

Tissue-type plasminogen activator induces synaptic vesicle endocytosis in cerebral cortical neurons

The release of the serine proteinase tissue-type plasminogen activator (tPA) from the presynaptic terminal of cerebral cortical neurons plays a central role in the development of synaptic plasticity, adaptation to metabolic stress and neuronal survival. Our earlier studies indicate that by inducing the recruitment of the cytoskeletal protein βII-spectrin and voltage-gated calcium channels to the active zone, tPA promotes Ca(2+)-dependent translocation of synaptic vesicles (SVs) to the synaptic release site where they release their load of neurotransmitters into the synaptic cleft. Here we used a combination of in vivo and in vitro experiments to investigate whether this effect leads to depletion of SVs in the presynaptic terminal. Our data indicate that tPA promotes SV endocytosis via a mechanism that does not require the conversion of plasminogen into plasmin. Instead, we show that tPA induces calcineurin-mediated dynamin I dephosphorylation, which is followed by dynamin I-induced recruitment of the actin-binding protein profilin II to the presynaptic membrane, and profilin II-induced F-actin formation. We report that this tPA-induced sequence of events leads to the association of newly formed SVs with F-actin clusters in the endocytic zone. In summary, the data presented here indicate that following the exocytotic release of neurotransmitters tPA activates the mechanism whereby SVs are retrieved from the presynaptic membrane and endocytosed to replenish the pool of vesicles available for a new cycle of exocytosis. Together, these results indicate that in murine cerebral cortical neurons tPA plays a central role coupling SVs exocytosis and endocytosis.

[The adhesive properties of two bonding systems to tetracycline stained dentin]

OBJECTIVE

To investigate and compare the bonding properties of Single Bond 2 and SE Bond to tetracycline stained dentin in vitro.

METHODS

Ten extracted tetracycline stained human teeth and ten extracted normal human teeth were collected and the occlusal dentin surfaces of all extracted teeth were exposed. The tetracycline stained teeth and normal teeth were divided into two groups, respectively and randomly, based on the adhesives applied. Total-etch adhesive(Single Bond 2) and self-etch adhesive(SE Bond) were used. After application of the adhesives to the dentin surfaces, composite crowns were built up. After 24 h water storage, the teeth were sectioned longitudinally into sticks(0.9 mm×0.9 mm bonding area) for micro tensile testing or micro Raman spectroscopy detection. Bonding strength(μTBS) and resin conversion rate were analyzed using one-way ANOVA.

RESULTS

The tetracycline Single Bond 2 group presented lower bonding strength[(16.17 ± 3.16) MPa] than the tetracycline SE Bond group[(25.82 ± 2.62) MPa], and also demonstrated lower bonding strength than the normal Single Bond 2 group[(29.13 ± 2.44) MPa] and the normal SE Bond group[(24.29±2.83) MPa] (P<0.05) , while there was no statistical differences among the other three groups(P>0.05). The resin conversion rate of tetracycline Single Bond 2 group[(55±6)%] was significantly lower than the tetracycline SE Bond group[(66±3)% ](P<0.05) and also lower than the normal Single Bond 2 group[(64 ± 5)%] and the normal SE Bond group[(65 ± 4)%] (P<0.05). No statistically significant differences were observed among the other three groups(P>0.05).

CONCLUSIONS

The bonding strength of total-etch adhesive system to the tetracycline stained dentin was significantly lower than that to the normal dentin.

On the acoustic analysis and optimization of ducted ventilation systems using a sub-structuring approach

This paper presents a general sub-structuring approach to predict the acoustic performance of ducted ventilation systems. The modeling principle is to determine the subsystem characteristics by calculating the transfer functions at their coupling interfaces, and the assembly is enabled by using a patch-based interface matching technique. For a particular example of a bended ventilation duct connecting an inlet and an outlet acoustic domain, a numerical model is developed to predict its sound attenuation performance. The prediction accuracy is thoroughly validated against finite element models. Through numerical examples, the rigid-walled duct is shown to provide relatively weak transmission loss (TL) across the frequency range of interest, and exhibit only the reactive behavior for sound reflection. By integrating sound absorbing treatment such as micro-perforated absorbers into the system, the TL can be significantly improved, and the system is seen to exhibit hybrid mechanisms for sound attenuation. The dissipative effect dominates at frequencies where the absorber is designed to be effective, and the reactive effect provides compensations at the absorption valleys attributed to the resonant behavior of the absorber. This ultimately maintains the system TL at a relatively high level across the entire frequency of interest. The TL of the system can be tuned or optimized in a very efficient way using the proposed approach due to its modular nature. It is shown that a balance of the hybrid mechanism is important to achieve an overall broadband attenuation performance in the design frequency range.

LaPtSb: a half-Heusler compound with high thermoelectric performance

The electronic and transport properties of the half-Heusler compound LaPtSb are investigated by performing first-principles calculations combined with semi-classical Boltzmann theory and deformation potential theory.

Comorbidity indices for clinical trials: adaptation of two existing indices for use with the FREEDOM trial in women with postmenopausal osteoporosis

Two comorbidity indices were adapted for use in the FREEDOM trial and significantly correlated with the number of medications and impaired health status at baseline. The indices have applications for the analysis of clinical trial data and would allow for the appropriate adjustment of comorbidities when evaluating clinical trial outcomes.

INTRODUCTION

The purpose of this study is to adapt two published comorbidity indices for use with the FREEDOM clinical trial evaluating postmenopausal women with osteoporosis.

METHODS

FREEDOM enrolled women aged 60-90 years with a bone mineral density T-score <-2.5 at the lumbar spine or total hip and ≥-4.0 at both sites. Comorbidity indices were calculated using methods described by Sangha (Arthritis Rheum 49:156-163, 2003) and Wolfe (J Rheumatol 37:305-315, 2010) following modification. The adapted Sangha index included 12 conditions with a summary score of 0-12; the adapted Wolfe index included 7 conditions with a weighted summary score of 0-8. Higher scores indicated greater comorbidity. A panel of clinicians independently reviewed subjects' medical histories using a systematic process based on Medical Dictionary for Regulatory Activities (MedDRA) preferred terms to map specified comorbid conditions. Spearman correlations between the adapted indices and baseline subject characteristics expected to be associated with comorbidities were examined.

RESULTS

Of the 7808 subjects in this study, 74 % had ≥1 comorbidities based on the adapted Sangha or Wolfe comorbidity indices. The mean (SD) adapted Sangha and Wolfe comorbidity indices were 1.4 (1.2) and 1.4 (1.3), respectively. Both indices correlated positively with age, body mass index, and the number of medications (r = 0.54 to 0.55) at baseline and inversely correlated with health-related quality of life (r = -0.22 to -0.30) (all P < 0.0001). Further, when either the adapted Sangha or Wolfe index was included as a covariate for assessing mortality over 36 months in the FREEDOM population, the hazard ratio of the comorbidity index indicated that the mortality risk increased by 27 or 28 %, respectively, for each unit increase in the adapted index (both P < 0.0001).

CONCLUSIONS

Our work suggests these comorbidity indices may be adapted for use with clinical trial data, thereby allowing for the appropriate adjustment and reporting of covariates in the evaluation of clinical trial outcomes in an osteoporotic population.

High thermoelectric performance of the distorted bismuth(110) layer

The thermoelectric properties of the distorted bismuth(110) layer are investigated using first-principles calculations combined with the Boltzmann transport equation for both electrons and phonons.

Structural and electronic properties of the heterointerfaces for Cu2ZnSnS4 photovoltaic cells: a density-functional theory study

Density-functional theory calculations have been performed to investigate the structural and electronic properties of the CdS/CZTS heterointerfaces in CZTS-based cells.

Effect of transvaginal ultrasound on human chorionic villus cell apoptosis during pregnancy

With the advancement of ultrasonic technology in recent years, sonography has become a common medical diagnostic tool, as it has elevated output sonic intensity and elongated exposure time. This study investigates the effect of ultrasound on human chorionic villus cell apoptosis during early pregnancy. Transvaginal ultrasound was performed for a total of 60 women who had undergone induced abortion at our hospital. They were randomly divided into the control, short ultrasound (10 min), and long ultrasound (20 min) groups (N = 20 each). Twenty-four hours after ultrasonic exposure, chorionic villus tissues were extracted during induced abortion, and were tested for cell apoptosis using flow cytometry. Bax and B cell lymphoma-2 (Bcl-2) protein levels were also quantified by immunohistochemistry. We found that the long ultrasound group had significantly higher cell apoptosis rates compared to the short ultrasound group, which in turn had higher rates compared to the control group (P < 0.05 in both cases). Bax protein levels were elevated in both the long and short ultrasound groups (P < 0.05). Bcl-2 proteins in two ultrasound groups, however, were downregulated as compared to those in the control group (P < 0.05). It is therefore possible that transvaginal sonography can potentiate the apoptosis of human chorionic villus cells by increasing the Bax/Bcl-2 protein ratio.

Interaction between mDia1 and ROCK in Rho-induced migration and adhesion of human dental pulp cells

AIM

To investigate the effects of mammalian homologue of Drosophila diaphanous-1(mDia1) and Rho-associated coiled-coil-containing protein kinase (ROCK) on the migration and adhesion of dental pulp cells (DPCs).

METHODOLOGY

Lysophosphatidic acid (LPA) was used to activate Rho signalling. mDia1 and ROCK were inhibited by short interfering RNA and the specific inhibitor, Y-27632, respectively. The migration of DPCs was assessed using the transwell migration assay and scratch test. Formation of cytoskeleton and focal adhesions(FAs) was observed by confocal laser scanning microscopy. Cell adhesion and spreading assays were performed. Phosphorylation of focal adhesion kinase (FAK) and paxillin was detected by Western blotting, and the bands were analysed using Adobe Photoshop CS5 software. All experiments were performed at least three times, and data were analysed with one-way anova and a post hoc test.

RESULTS

LPA-triggered activation of Rho and inhibition of ROCK significantly increased the cell migration rate. Cell migration was inhibited by silencing mDia1. mDia1 silencing and ROCK inhibition suppressed the LPA-induced formation of the cytoskeleton, FA and phosphorylation of FAK and paxillin. Inhibition of ROCK or mDia1 facilitated early cell adhesion and spreading; by contrast, the combined inhibition of ROCK and mDia1 neutralized these effects.

CONCLUSIONS

mDia1 promoted RhoA-induced migration of DPCs, but ROCK had an opposite effect. Both mDia1 and ROCK participated in cytoskeleton formation and adhesion of DPCs. The interactions between mDia1 and ROCK might influence dental pulp repair by determining the migration and adhesion of DPCs.

Effects of feed intake and genetics on tissue nitrogen-15 enrichment and feed conversion efficiency in sheep

This study investigated the effects of sheep genetics and feed intake on nitrogen isotopic fractionation (ΔN) and feed conversion efficiency (FCE; live weight gain/DMI), using a 2 × 2 factorial design, with 2 levels of genetic merit for growth (high vs. low) and 2 levels of feed intake (110 vs. 170% of ME for maintenance [MEm]). No effect of genetic merit was detected for live weight gain ( = 0.64), FCE ( = 0.46), plasma urea nitrogen ( = 0.52), plasma glucose ( = 0.78), and ΔN of wool ( = 0.45), blood ( = 0.09), and plasma ( = 0.51). Sheep receiving 170% of MEm had 175% higher live weight gain ( < 0.001) and 77% higher FCE ( < 0.001) than sheep receiving 110% of MEm. There was no difference among treatments at the beginning of the study for either blood or plasma ∆N, but the treatment groups started to diverge in blood and plasma ∆N at 21 and 7 d, respectively. Blood, plasma, and wool samples were enriched in N compared with feed. There was a higher blood, plasma, and wool ∆N for the low feed intake group than the high feed intake group ( < 0.001 in all cases). Across the 4 treatment groups, higher FCE in sheep was associated with lower ∆N for plasma, blood, and wool. Overall, the results are consistent with the potential of ∆N as a rapid, low-cost biomarker of FCE in sheep, despite there being no effects of genetic treatment on FCE and ∆N.

d-Alanine metabolism is essential for growth and biofilm formation of Streptococcus mutans

Part of the d-alanine (d-Ala) metabolic pathway in bacteria involves the conversion of l-alanine to d-Ala by alanine racemase and the formation of d-alanyl-d-alanine by d-alanine-d-alanine ligase, the product of which is involved in cell wall peptidoglycan synthesis. At present, drugs that target the metabolic pathway of d-Ala are already in clinical use - e.g. d-cycloserine (DCS) is used as an antibiotic against Mycobacterium tuberculosis. Streptococcus mutans is the main cariogenic bacterium in the oral cavity. Its d-Ala metabolism-associated enzymes alanine racemase and d-alanine-d-alanine ligase are encoded by the genes smu.1834 and smu.599, respectively, which may be potential targets for inhibitors. In this study, the addition of DCS blocked the d-Ala metabolic pathway in S. mutans, leading to bacterial cell wall defects, significant inhibition of bacterial growth and biofilm formation, and reductions in extracellular polysaccharide production and bacterial adhesion. However, the exogenous addition of d-Ala could reverse the inhibitory effect of DCS. Through the means of drug regulation, our study demonstrated, for the first time, the importance of d-Ala metabolism in the survival and biofilm formation of S. mutans. If the growth of S. mutans can be specifically inhibited by designing drugs that target d-Ala metabolism, then this may serve as a potential new treatment for dental caries.

The PPI network and clusters analysis in glioblastoma

OBJECTIVE

Glioblastoma is the most aggressive tumor of the brain. To further understand its molecular mechanism, we carried out a systemic bioinformatics study of gene chips downloaded from Gene Expression Omnibus database.

MATERIALS AND METHODS

LIMMA package in R language was used to identify the differentially expressed genes (DEGs) between glioblastoma samples and normal controls.

RESULTS

Further, we constructed protein-protein interaction networks by mapping the DEGs into PPI data and identified network clusters in these networks. The results revealed that expression of 516 genes, which are mainly involved in phosphate metabolic process and signal transduction, were altered in glioblastoma samples. LYN, CD22 and LCP2 form a densely protein complex in the PPI network.

CONCLUSIONS

Our results suggest that LYN, CD22 and LCP2 play important roles in the occurrence and progression of glioblastoma.

Precision Measurement of the Helium Flux in Primary Cosmic Rays of Rigidities 1.9 GV to 3 TV with the Alpha Magnetic Spectrometer on the International Space Station

Knowledge of the precise rigidity dependence of the helium flux is important in understanding the origin, acceleration, and propagation of cosmic rays. A precise measurement of the helium flux in primary cosmic rays with rigidity (momentum/charge) from 1.9 GV to 3 TV based on 50 million events is presented and compared to the proton flux. The detailed variation with rigidity of the helium flux spectral index is presented for the first time. The spectral index progressively hardens at rigidities larger than 100 GV. The rigidity dependence of the helium flux spectral index is similar to that of the proton spectral index though the magnitudes are different. Remarkably, the spectral index of the proton to helium flux ratio increases with rigidity up to 45 GV and then becomes constant; the flux ratio above 45 GV is well described by a single power law.