Development and uniqueness test of highly selective atomic topological indices based on the number of attached hydrogen atoms

On the basis of the atomic graph-theoretical index - aEAID (atomic Extended Adjacency matrix IDentification) and molecular adjacent topological index - ATID (Adjacent Topological IDentification) suggested by one of the authors (Zhang Q), a highly selective atomic topological index - aATID (atomic Adjacent Topological IDentification) index was suggested to identify the equivalent atoms in this study. The aATID index of an atom was derived from the number of the attached hydrogen atoms of the atom but omitting bond types. In this case, the suggested index can be used to identify equivalent atoms in chemistry but perhaps not equivalent in the molecular graph. To test the uniqueness of aATID indices, the virtual atomic data sets were derived from alkanes containing 15-20 carbon atoms and the isomers of Octogen, as well as a real data set was derived from the NCI database. Only four pairs of atoms from alkanes containing 20 carbons can't be discriminated by aATID, that is, four pairs of degenerates were found for this data set. To solve this problem, the aATID index was modified by introducing distance factors between atoms, and the 2-aATID index was suggested. Its uniqueness was examined by 5,939,902 atoms derived from alkanes containing 20 carbons and further 16,166,984 atoms from alkanes of 21 carbons, and no degenerates were found. In addition, another large real data set of 16,650,688 atoms derived from the PubChem database was also used to test the uniqueness of both aATID and 2-aATID. As a result, each atom was successfully discriminated by any of the two indices. Finally, the suggested aATID index was applied to the identification of duplicate atoms as data pretreatment for QSPR (Quantitative Structure-Property Relationships) studies.

Taraxacum mongolicum polysaccharide promotes white adipocyte browning by regulating miR-134-3p via Akt/GSK-3β signalling

In recent years, the incidence of obesity has gradually increased due to high calorie diets and lack of exercise. Reducing energy intake or increasing energy expenditure is the most effective way to promote weight loss and reduce lipid levels. Activated beige adipocytes can increase energy consumption in the body, and inducing conversion of white adipocytes to brown can prevent and treat obesity. Taraxacum mongolicum polysaccharide (TMP) is a plant polysaccharide that has been widely used for its anti-tumour and antioxidant properties. However, little is known about the role of TMP in the browning of sheep white adipose tissue. The aim of this study was to explore the potential mechanism of TMP and miR-134-3p in regulating the browning of sheep white adipocytes, as well as the regulatory relationship between TMP and miR-134-3p. Our results showed that TMP had a positive regulatory effect on the proliferation and browning of sheep white adipocytes. In addition, miR-134-3p significantly inhibited browning activity and AKT/GSK-3β signalling. Importantly, we found that TMP function required miR-134-3p mediation in the browning of sheep white adipocytes. Overall, our results suggested that TMP recruited beige adipocytes by regulating AKT/GSK-3β signalling via miR-134-3p.

Guided self-help mindfulness-based intervention for increasing psychological resilience and reducing job burnout in psychiatric nurses: A randomized controlled trial

AIMS

The present study aimed to explore the effects of a guided self-help mindfulness intervention on psychological resilience and job burnout among psychiatric nurses.

BACKGROUND

Psychiatric nurses work in challenging and potentially high stress settings. Mindfulness interventions can improve psychological resilience and reduce job burnout of nurses. However, face-to-face delivery of mindfulness interventions may be inconvenient for individuals. Guided self-help interventions may be more accessible.

METHODS

This randomized controlled trial was conducted from January to August 2022. One hundred and eighteen psychiatric nurses were randomized into the intervention and control groups. The individuals in the intervention group received an 8-week guided self-help mindfulness intervention, while the individuals in the control group received a psycho-educational brochure. The Five Facet Mindfulness Questionnaire, the Connor-Davidson Resilience Scale and the Maslach Burnout Inventory-Human Services Survey were used to evaluate the levels of mindfulness, psychological resilience and job burnout, respectively.

RESULTS

After an 8-week intervention, compared with the control group, the levels of mindfulness and psychological resilience were higher, while the level of job burnout was lower in the intervention group.

CONCLUSIONS

The guided self-help mindfulness intervention can improve psychological resilience and reduce job burnout among psychiatric nurses.

Machine Learning to Predict Homolytic Dissociation Energies of C-H Bonds: Calibration of DFT-based Models with Experimental Data

Random Forest (RF) QSPR models were developed with a data set of homolytic bond dissociation energies (BDE) previously calculated by B3LYP/6-311++G(d,p)//DFTB for 2263 sp3C-H covalent bonds. The best set of attributes consisted in 114 descriptors of the carbon atom (counts of atom types in 5 spheres around the kernel atom and ring descriptors). The optimized model predicted the DFT-calculated BDE of an independent test set of 224 bonds with MAE=2.86 kcal/mol. A new data set of 409 bonds from the iBonD database (http://ibond.nankai.edu.cn) was predicted by the RF with a modest MAE (5.36 kcal/mol) but a relatively high R² (0.75) against experimental energies. A prediction scheme was explored that corrects the RF prediction with the average deviation observed for the k nearest neighbours (KNN) in an additional memory of experimental data. The corrected predictions achieved MAE=2.22 kcal/mol for an independent test set of 145 bonds and the corresponding experimental bond energies.

An Unsupervised Video Stabilization Algorithm Based on Key Point Detection

In recent years, video stabilization has improved significantly in simple scenes, but is not as effective as it could be in complex scenes. In this study, we built an unsupervised video stabilization model. In order to improve the accurate distribution of key points in the full frame, a DNN-based key-point detector was introduced to generate rich key points and optimize the key points and the optical flow in the largest area of the untextured region. Furthermore, for complex scenes with moving foreground targets, we used a foreground and background separation-based approach to obtain unstable motion trajectories, which were then smoothed. For the generated frames, adaptive cropping was conducted to completely remove the black edges while maintaining the maximum detail of the original frame. The results of public benchmark tests showed that this method resulted in less visual distortion than current state-of-the-art video stabilization methods, while retaining greater detail in the original stable frames and completely removing black edges. It also outperformed current stabilization models in terms of both quantitative and operational speed.

A bivalent Tim-3/PD-1 bispecific antibody for the treatment of PD-1 antibody resistant or refractory NSCLC

e14597

Background: Immune checkpoint inhibitors (ICI) PD-1/PD-L1 antibody are key drugs for the treatment of non-small cell lung cancer (NSCLC). Bispecific antibody is one of the strategies aimed at the clinical needs for NSCLC patients who are resistant to or refractory from ICI treatment. Tim-3, one of the next generation of ICB targets, is co-expressed on exhausted T cells with PD-1. It is also expressed by innate immune populations, including NK and DC. Dual blocking PD-1 and Tim-3 not only on T cells but also on DC, NK cells may achieve better clinical benefit. Methods: A bivalent to both Tim-3 and PD-1 bispecific antibody (Bis5) was developed and is in Phase I clinical trials for NSCLC patients who are resistant to or refractory from PD-1 antibody treatment. Results: Bis5 showed affinity of 5-8 nM to both Tim-3 and PD-1. Moreover, Bis5 showed better cell activity than Tim-3 and PD-1 antibody combination to activated T cell as well as NK and DC. Bis5 showed 77%-88% tumor inhibition which is close to PD-1 antibody alone in MC38 model. Neither PD-1 antibody or PD-1 and Tim-3 antibody combination show any activity in CT26 model while Bis5 showed significant tumor inhibition activity and doubled the survival rate. The highest non-severe toxicity dose (HNSTD) was 200mpk in monkeys. ADA were 33.3% (2/6), 83.3% (5/6), and 0.0% (0/6) at doses of 2, 10, and 50 mpk, respectively. The T1/2 were 31.7-66.5 h for doses 2-50 mpk. Conclusions: A Phase I, multicenter, open-label study to evaluate the safety, tolerability, pharmacokinetics, pharmacodynamics, immunogenicity and preliminary efficacy of Bis5 in patients with advanced and/or metastatic solid tumors has started. Seven cohorts (0.1, 0.3, 1, 3, 6, 10, 15 mg/kg) are planned to be enrolled sequentially in the dose escalation part. In the expansion part, a cohort group of 10 patients is planned for post PD-1 treated NSCLC as the second or third line treatment.

A peptide fused to CLDN18.2 antibody targeting the tumor antigen associated CD8+T cells for the treatment of pancreatic cancers

e16240

Background: PD-1/PD-L1-targeted immunotherapies have become critical roles in the treatment for many tumors. However, there is limited progress in gastrointestinal cancers, especially in pancreatic ductal adenocarcinoma (PDAC). PDAC is low immunogenicity. PDAC microenvironment is immunosuppressive. More than 70% PDACs have few or no CD8+ T cells around the tumor cell or in the tumor microenvironment. Therefore, immunotherapy like PD-1/PD-L1 antibody alone is rarely effective for PDACs. Methods: Some cytokine or analogs may activate CD8+ T cells. An analog specifically activating tumor antigen associated (TAA) CD8+ T cells was fused to anti-CLDN18.2 antibody. Results: The specific bi-functional molecule (Bis2) has high affinity to human anti-CLDN18.2 (14pM) and CD8+T cells. Bis2 shows significant in vivo efficacy at 0.1 mpk. The efficacy lasts for more than 24 days, only given two doses at day 1 and day 3, respectively. IHC shows that the tumor infiltrated CD8+T cells significantly increased and IFNγ secretion enhanced as well. The IHC results are consistent with the mechanism that Bis2 induces TAA CD8+ T cell proliferation and prevents CD8+T cells from IFNγ-mediated apoptosis. Moreover, Bis2 also shows 100% tumor inhibition in combination with either chem (L-OHP+5FU) or PD-1 antibody in vivo which is better than chem in combination with PD-1 antibody. Bis2 also shows 60% tumor inhibition at 1mpk in CLDN18.2 negative cell based in vivo model. Bis2 shows ADA in monkeys in two weeks by dosing weekly. The repeated doses toxicity study shows an increase of MONO and %MONO and decrease in RBC, HGB, HCT, and MCHC. The HNSTD was 3mpk. The T1/2 was 40h. Conclusions: The Phase I study in advanced solid tumors is ongoing. The study uses accelerated titration starting from 0.01mpk combined with a BOIN design, maximum patient size of 36. In the expansion part, two cohorts of 10 CLDN18.2+ pancreatic cancer patients are planned for the treatment of Bis2 alone or Bis2 in combination with chemotherapy, respectively.

Gene mapping reveals the association between tyrosine protein kinase Abl1 and the silk yield of Bombyx mori

The Z chromosome of the silkworm contains a major gene that influences silk yield. This major locus on chromosome Z accounts for 35.10% of the phenotypic variance. The location and identification of the gene have been a focus of silkworm genetics research. Unfortunately, identification of this gene has been difficult. We used extreme phenotype subpopulations and selected from a backcross population, BC₁ M, which was obtained using the high-yield strain 872B and the low-yield strain IS-Dazao as parents, for mapping the gene on the chromosome Z. The candidate region was narrowed down to 134 kb at the tip of the chromosome. BmAbl1 in this region correlated with silk gland development by spatiotemporal expression analysis. This gene was differentially expressed in the posterior silk glands of the high- and low-yield strains. In BmAbl1, an insertion-deletion (indel) within the 10th exonic region and an SNP within the 6th intronic region were detected and shown to be associated with cocoon shell weight in 84 Bombyx mori strains with different yields. Nucleotide diversity analysis of BmAbl1 and its 50 kb flanking regions indicated that BmAbl1 has experienced strong artificial selection during silkworm domestication. This study is the first to identify the genes controlling silk yield in the major QTL of the Z chromosome using forward genetics.

A proof-of-concept study of an automated solution for clinical metagenomic next-generation sequencing

AIMS

Metagenomic next-generation sequencing (mNGS) has been utilized for diagnosing infectious diseases. It is a culture-free and hypothesis-free nucleic acid test for diagnosing all pathogens with known genomic sequences, including bacteria, fungi, viruses and parasites. While this technique greatly expands the clinical capacity of pathogen detection, it is a second-line choice due to lengthy procedures and microbial contaminations introduced from wet-lab processes. As a result, we aimed to reduce the hands-on time and exogenous contaminations in mNGS.

METHODS AND RESULTS

We developed a device (NGSmaster) that automates the wet-lab workflow, including nucleic acid extraction, PCR-free library preparation and purification. It shortens the sample-to-results time to 16 and 18·5 h for DNA and RNA sequencing respectively. We used it to test cultured bacteria for validation of the workflow and bioinformatic pipeline. We also compared PCR-free with PCR-based library prep and discovered no differences in microbial reads. Moreover we analysed results by automation and manual testing and found that automation can significantly reduce microbial contaminations. Finally, we tested artificial and clinical samples and showed mNGS results were concordant with traditional culture.

CONCLUSION

NGSmaster can fulfil the microbiological diagnostic needs in a variety of sample types.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study opens up an opportunity of performing in-house mNGS to reduce turnaround time and workload, instead of transferring potentially contagious specimen to a third-party laboratory.

Identification and effect of Zf-AD-containing C2H2 zinc finger genes on BmNPV replication in the silkworm (Bombyx mori)

Zf-AD-containing C2H2 zinc -finger genes (ZAD) are uniquely present and have lineage-specific expansion in arthropods. Arthropods are also the hosts of Baculoviruses. We studied the possible relationship between the lineage-specific expansion of ZAD genes and arthropod-Baculovirus co-evolution. We used the silkworm (Bombyx mori) as a model. We identified 73 ZAD genes (BmZAD) in the silkworm. Sequence-based similarity analysis showed that nine clusters involving 28 BmZADs may have undergone species-specific expansion in the silkworm. Expression pattern analysis showed that the BmZADs were divided into five groups. Group I comprised 10 genes with high expression in multiple tissues, suggesting that BmZADs may play roles in the development of various tissues. We identified six BmZADs that could be induced by the Nucleopolyhedrovirus (BmNPV). Among them, BmZAD69 expression is capable of responding to BmNPV infection, and the ZAD domain is indispensable for the function of BmZAD69 in BmNPV replication. We also detected a 3 bp deletion at 1.7 kb upstream of BmZAD69, which may make it more sensitive to BmNPV infection, and thus elevate the BmNPV resistance in Qiufeng_N, a strain with strong virus resistance. These data suggest that BmZADs may be involved in BmNPV infection and that ZAD genes may play a role in arthropod-Baculovirus co-evolution.

Synthesis and application of gas diffusion cathodes in an advanced type of undivided electrochemical cell

This paper reports the oxidation of Remazol black B dye by employing iron ions catalyst based gas diffusion cathodes, (GDCs). A GDC was synthesized by using a layer of carbon black and iron ions catalyst for oxygen reduction to hydrogen peroxide. The results demonstrated around 97% decolorization of Remazol black-B dye for 50 min by iron ions catalyst based GDC. The degradation study was performed under electrogenerated hydrogen peroxide at a constant voltage of - 0.6 V vs Hg/HgSO4 in which the rate of degradation was correlated with hydrogen peroxide production. Overall, the GDC's found to be effective method to degrade the dyes via electro-Fenton.

Whole-genome resequencing reveals loci under selection during silkworm improvement

Breeding or genetic improvement refers to the process of artificial selection following domestication; as such, it has had a major influence on modern agriculture and animal production. Improvement generally focuses on traits that greatly affect the economic performance. Therefore, understanding the genetic basis underlying improvement will contribute to the identification of genes controlling economic traits and will facilitate future crop and animal breeding. However, genome-wide study of the molecular basis underlying improvement remains rare. The silkworm is a unique, entirely domesticated economically important invertebrate; genetic improvement has had a huge effect on the silkworm regarding silk-related traits. Herein, we performed whole-genomic sequencing on local and genetically improved silkworm lines to identify the genomic regions under strong selection in silkworm breeding/improvement. By genomic-wide selective sweeping analysis, we identified 24 genomic regions with strong selection signals, eight of which contained 13 candidate genes underlying silkworm breeding. Interestingly, six of these genes were annotated with functions related to neural signal response. Among the six genes, BGIBMGA004050 encodes silkworm CREB-regulated_transcription_coactivator_1 (BmCRTC1), which was reported to be involved in energy-sensing pathways. These results suggested that improvement may have affected the nervous system of the silkworm. This research will provide new insights into the genetic basis underlying the genetic improvement of silkworms and possibly of other species.

[Correlation analysis between prostate imaging report and data system score and pathological results of prostate cancer]

Objective: To explore the correlation between prostate imaging report and data system (PI-RADS) score and international society of uological pathology (ISUP) grade of prostate cancer (PCa) and the role of PI-RADS score in predicting the pathological features of clinically significant PCa (csPCa), positive surgical margin and pathological upgrade. Methods: The pathologically positive patients with multi-parameter magnetic resonance image (mpMRI) were included in this study. The patients with prostate specific antigen (PSA)<100 μg/L were divided into two groups: biopsy group (n=523) and RP group (n=215). The correlation between PI-RADS score and ISUP grade and the accuracy of predicting csPCa in the two groups were evaluated. In the RP group, the correlation between PI-RADS score and postoperative pathological grade or degradation and positive incisal margin was further discussed. The patients with PSA≥100 μg/L (171cases in biopsy group and 6 cases in RP group) were not included in the statistical analysis, and the results were simply described. Results: The age, prostate volume, and PSA level of biopsy group and RP group was (72±8) years vs (68±7) years, 48.3 (32-57) cm(3) vs 47.2 (32-54) cm(3), and 26.3(10.2-34.2)μg/L vs 21.7 (9.24-23.95)μg/L, respectively. The PI-RADS scores ≤ 3,4, and 5 in the biopsy group were 109,97, and 317 respectively, and those in the RP group were 61,55, and 99 respectively. There were significant differences in the composition of ISUP grades of different PI-RADS scores between the two groups (P<0.001), and there was a positive correlation between the two groups (r=0.493 in the biopsy group, r=0.671 in the RP group, both P<0.001). Using PI-RADS score to predict csPCa, biopsy group (AUC=0.764, P<0.001, 95%CI:0.710-0.819) and RP group (AUC=0.807, P<0.001, 95%CI:0.735-0.879) had certain accuracy. The PI-RADS score combined with PSA could improve the accuracy of csPCa prediction in the biopsy group (AUC=0.795,P<0.001, 95% CI:0.746-0.843) and the RP group (AUC=0.852, P<0.001, 95%CI:0.789-0.915). Compared with the pathological results of biopsy in the RP group, 52.6% of the patients showed upgrade and degrade of ISUP, and there was insignificant difference in the composition of PI-RADS scores between upgraded and degraded patients (P>0.05). However, 41.7%(27/65) of the patients with ISUP grade 1 biopsies had pathological upgrades that the patients with PI-RADS ≤ 3 accounted for 33.3%, while the patients with PI-RADS>3 accounted for 66.7%, and there was significant difference between the two groups (P<0.05). After RP, 43.3% of the patients had positive surgical margins, and the patients with PI-RADS score ≤ 3, 4 and 5 were 13 (14%), 24 (25.8%) and 56 (60.2%), respectively, while the PI-RADS scores of patients with negative surgical margin were 48 (39.3%), 31(25.4%) and 43(35.2%), respectively. There was significant difference between the two groups (P<0.001). The higher the PI-RADS score, the greater the possibility of the positive surgical margin. For the patients with PSA ≥ 100 μg/L, 98.8% (169/171) patients in the biopsy group had a PI-RADS score 5. The pathological results of all patients were csPCa, of which 85.4% (146/171) had ISUP grade ≥ 4. Among them, 6 cases underwent RP, 5 cases had ISUP grade ≥ 4, all surgical margin were positive, 5 cases had seminal vesicle invasion, 3 cases had capsule invasion and 3 cases had positive pelvic lymph nodes. Conclusion: ThePI-RADS score is correlated with the ISUP grade of PCa. Combined with PSA can accurately predict csPCa. At the same time, the higher PI-RADS score, the more likely the patients with positive incisal margin after RP and Gleason score of 3+3=6 at the time of puncture will be upgraded pathologically.

Tailored Plasmons in Pentacene/Graphene Heterostructures with Interlayer Electron Transfer

van der Waals (vdW) heterostructures, which are produced by the precise assemblies of varieties of two-dimensional (2D) materials, have demonstrated many novel properties and functionalities. Here we report a nanoplasmonic study of vdW heterostructures that were produced by depositing ordered molecular layers of pentacene on top of graphene. We find through nanoinfrared (IR) imaging that surface plasmons formed due to the collective oscillations of Dirac Fermions in graphene are highly sensitive to the adjacent pentacene layers. In particular, the plasmon wavelength declines systematically but nonlinearly with increasing pentacene thickness. Further analysis and density functional theory (DFT) calculations indicate that the observed peculiar thickness dependence is mainly due to the tunneling-type electron transfer from pentacene to graphene. Our work unveils a new method for tailoring graphene plasmons and deepens our understanding of the intriguing nano-optical phenomena due to interlayer couplings in novel vdW heterostructures.

[Effect of multimodal analgesia using periprostatic nerve block anesthesia combined with flurbiprofen in transperineal template-guided prostate biopsy]

Objective: To evaluate the effect of multimodal analgesia using periprostatic nerve block anesthesia (PNB) combined with flurbiprofen in patients undergoing transperineal template-guided prostate biopsy (TTPB). Methods: Totally 166 patients (aged (68.2±9.1) years, range: 47 to 81 years) who received TTPB from October 2017 to June 2018 at Department of Urology, Northern Jiangsu People's Hospital Affiliated to Yangzhou University were enrolled prospectively. All the patients were randomly divided into 2 groups. The observation group (n=79) was given flurbiprofen axetil 1 mg/kg intravenously for half an hour before operation and lidocaine was used for PNB before the biopsy. The control group (n=87) was given normal saline combined with PNB. A visual analog scale (VAS) and visual numeric scale (VNS) were used to assess the patients' pain and quantify their satisfaction at two time points: VAS-1 and VNS-1: during biopsy procedure, VAS-2 and VNS-2: 30 min after the procedure. The date were compared by t test, χ(2) test, Fisher exact test and two-way repeated measures anova analysis between the 2 groups. Results: The age, total prostate volume, serum prostate-specific antigen and the number of cores were comparable among the 2 groups (P>0.05). The VAS-1 scores of the control group and the observation group were 2.8±1.7, 1.9±1.2, respectively, and the VNS-1 were 3.1±0.7, 3.4±0.3, respectively. The VAS-1 were significantly lower in observation group than in control group (F=3.904, P=0.000). Conversely, the VNS-1 were higher in observation group (F=3.526, P=0.000). At 30-minute postoperative, the VAS-2 and VNS-2 were 0.7±0.4 and 3.7±0.2 in the control group, respectively. The VAS-2 and VNS-2 were 0.6±0.5 and 3.8±0.1 in the observation group, respectively. There were no significant differences in the pain scores or the satisfaction scores between the 2 groups (F=1.429, 2.825; P=0.136, 0.083). The incidence of overall complications was 26.4% (23/87) in the control group and 25.3% (20/79) in the observation group, with no statistical difference between the 2 groups (χ(2)=0.027, P=0.869). And the complications had no statistically significant difference among the 2 groups including hematuria, urinary retention, infection, hematospermia, vascular and neurological reactions, nausea, vomiting, dizziness, headache, and respiratory depression (P>0.05). Conclusion: The multimodal analgesia induced by PNB and flurbiprofen could effectively relieve the pain for patients who received TTPB.

[Precision evaluation of immune status and its significance in sepsis after burns or trauma]

Sepsis induced by major burns, trauma, and hemorrhage, remains a major cause of death of patients in intensive care units, and it may result in both the widespread activation and dysfunction of the innate as well as adaptive responses in host immune system. A large amount of information concerning subsets of innate and adaptive immune cells in sepsis has implicated that these cells, including neutrophils, macrophages, dendritic cells, T lymphocytes, regulatory T lymphocytes, and natural killer cells, have profound effects on immunoreactivity during acute insults or sepsis through modulating multiple receptor expressions or cytokine secretion, in turn contributing to the development and outcome of sepsis. It is of great significance that precision monitoring of immune function and the related indicators might help to assess the risk of secondary infection, the prognosis of septic patients, and guide the treatment of septic complications.

[Cloning and function analysis of elongase of very long chain fatty acid gene Bmelo424 in silkworm]

Genes belonging to the elongases of very long chain fatty acid (ELOVL) family affect many physiological functions in organism. In this paper, Bmelo424 gene, a member of the ELOVL family in silkworm, was cloned and its ORF was 558 bp. Its protein sequence was predicted to have four transmembrane domains, six serine phosphorylation sites, eight threonine phosphorylation sites and four tyrosine phosphorylation sites, and its subcellular localization was in the endoplasmic reticulum. Secondary structure analysis showed that the percentage of alpha-helix and beta-strand was 26.7% and 20% respectively. The results of fluorescence quantitative PCR showed that Bmelo424 gene was expressed in all tissues of silkworm, especially with the highest expression in head. By heterologous expression of Bmelo424 gene in Saccharomyces cerevisiae, the effect of Bmelo424 gene on fatty acid elongation was studied. GC-MS results indicated that the fatty acid content of C16:1n-7 in S. cerevisiae with pYES2-Bmelo424 recombinant plasmid increased significantly, whereas the content of C16:0, C18:0 and C18:1n-9 decreased. The results of temperature stress revealed that Bmelo424 gene could improve the low temperature adaptability of S. cerevisiae, but its high temperature adaptability decreased. This provides a reference for exploring the function of Bmelo424 gene in silkworm.

Identification of Genes that Control Silk Yield by RNA Sequencing Analysis of Silkworm (Bombyx mori) Strains of Variable Silk Yield

Silk is an important natural fiber of high economic value, and thus genetic study of the silkworm is a major area of research. Transcriptome analysis can provide guidance for genetic studies of silk yield traits. In this study, we performed a transcriptome comparison using multiple silkworms with different silk yields. A total of 22 common differentially expressed genes (DEGs) were identified in multiple strains and were mainly involved in metabolic pathways. Among these, seven significant common DEGs were verified by quantitative reverse transcription polymerase chain reaction, and the results coincided with the findings generated by RNA sequencing. Association analysis showed that BGIBMGA003330 and BGIBMGA005780 are significantly associated with cocoon shell weight and encode uridine nucleosidase and small heat shock protein, respectively. Functional annotation of these genes suggest that these play a role in silkworm silk gland development or silk protein synthesis. In addition, we performed principal component analysis (PCA) in combination with wild silkworm analysis, which indicates that modern breeding has a stronger selection effect on silk yield traits than domestication, and imply that silkworm breeding induces aggregation of genes related to silk yield.

Human tissue kallikrein 1 ameliorates erectile function via modulation of macroautophagy in aged transgenic rats

Previously, we have demonstrated that human tissue kallikrein 1 (hKLK1) improves age-related erectile dysfunction (ED). Autophagy has been implicated in age-related diseases, including ED. However, the molecular mechanisms underlying hKLK1-mediated amelioration of age-related ED via regulation of autophagy remains unknown. To explore the potential mechanism, male wild-type Sprague-Dawley rats (WTR) and transgenic rats harboring human KLK1 (TGR) were bred till 4 or 18 months of age and divided into three groups: young WTR (yWTR) as the control group, aged WTR (aWTR) group, and aged TGR (aTGR) group. The erectile function of each rat was evaluated using cavernous nerve electrostimulation. The ratio of intracavernous pressure/mean arterial pressure (ICP/MAP) and total ICP were also measured. Western blotting, immunohistochemistry, and transmission electron microscopy were performed to detect the levels of autophagy. The expression levels of related signaling pathways were determined by western blotting and immunohistochemistry. We found that hKLK1 improved the impaired erectile function of aged rats. Compared to the yWTR and aTGR groups, the aWTR group showed reduced smooth muscle/collagen ratio, fewer autophagosomes, and lower expression of Beclin 1 and LC3-II, which indicate impaired smooth muscle function and low level of autophagy in the smooth muscle cells. Moreover, the PI3K/Akt/mTOR signaling pathway, which is considered to be a negative regulator of autophagy, was upregulated in the aWTR group. hKLK1 may partially restore erectile function in aged transgenic rats by upregulating protective autophagy via the PI3K/Akt/mTOR pathway. These observations indicate that hKLK1 is a potential gene therapy candidate for age-related ED.

Genome-wide identification and analysis of elongase of very long chain fatty acid genes in the silkworm, Bombyx mori

Very long chain fatty acids (VLCFAs), such as sphingolipids, are components of cellular lipids, which are essential for cell proliferation. Mutations in the genes that encode proteins participating in VLCFA biosynthesis may cause inherited diseases, such as macular degeneration. Elongases of very long chain fatty acid (ELOVL) are enzymes that are involved in the biosynthesis of VLCFAs. Here, a total of 13 ELOVL genes, distributed across three chromosomes, were identified in the silkworm genome; all the ELOVL members contain a distinct ELO domain and a conserved HXXHH motif. Phylogenetic reconstruction was performed to analyze the evolutionary relationships among different species and to predict gene functions. The 13 ELOVL genes were assigned to the ELOVL3/6, ELOVL1/7, and ELOVL4 clades. Microarray and semiquantitative PCR analyses indicated that these genes are differentially expressed among various tissues, in turn suggesting functional divergence in the growth and development of each tissue. Further investigation showed that the expression level of the BGIBMGA000424 gene is significantly negatively correlated with the cocoon-shell weight among different silkworm strains. Taken together, the present study is the first comprehensive analysis of ELOVL genes in silkworm, and the results may serve as a foundation for further analysis of the physiological functions of ELOVL genes in silkworm.

Polydopamine–polyethylene glycol–albumin antifouling coatings on multiple substrates

Polydopamine–PEG coatings on different substrates: effects of PDA layer properties on PEG grafting and anti-biofouling properties.

Real-Space Imaging of the Tailored Plasmons in Twisted Bilayer Graphene

We report a systematic plasmonic study of twisted bilayer graphene (TBLG)-two graphene layers stacked with a twist angle. Through real-space nanoimaging of TBLG single crystals with a wide distribution of twist angles, we find that TBLG supports confined infrared plasmons that are sensitively dependent on the twist angle. At small twist angles, TBLG has a plasmon wavelength comparable to that of single-layer graphene. At larger twist angles, the plasmon wavelength of TBLG increases significantly with apparently lower damping. Further analysis and modeling indicate that the observed twist-angle dependence of TBLG plasmons in the Dirac linear regime is mainly due to the Fermi-velocity renormalization, a direct consequence of interlayer electronic coupling. Our work unveils the tailored plasmonic characteristics of TBLG and deepens our understanding of the intriguing nano-optical physics in novel van der Waals coupled two-dimensional materials.

Imaging the Localized Plasmon Resonance Modes in Graphene Nanoribbons

We report a nanoinfrared (IR) imaging study of the localized plasmon resonance modes of graphene nanoribbons (GNRs) using a scattering-type scanning near-field optical microscope (s-SNOM). By comparing the imaging data of GNRs that are aligned parallel and perpendicular to the in-plane component of the excitation laser field, we observed symmetric and asymmetric plasmonic interference fringes, respectively. Theoretical analysis indicates that the asymmetric fringes are formed due to the interplay between the localized surface plasmon resonance (SPR) mode excited by the GNRs and the propagative surface plasmon polariton (SPP) mode launched by the s-SNOM tip. With rigorous simulations, we reproduce the observed fringe patterns and address quantitatively the role of the s-SNOM tip on both the SPR and SPP modes. Furthermore, we have seen real-space signatures of both the dipole and higher-order SPR modes by varying the ribbon width.

Isolation, identification and fibrolytic characteristics of rumen fungi grown with indigenous methanogen from yaks (Bos grunniens) grazing on the Qinghai-Tibetan Plateau

AIM

To obtain co-cultures of anaerobic fungi and their indigenously associated methanogens from the rumen of yaks grazing on the Qinghai-Tibetan Plateau and investigate their morphology features and ability to degrade lignocellulose.

METHODS AND RESULTS

Twenty fungus-methanogen co-cultures were obtained by Hungate roll-tube technique. The fungi were identified as Orpinomyces, Neocallimastix and Piromyces genera based on the morphological characteristics and internal transcribed spacer 1 sequences analysis. All methanogens were identified as Methanobrevibacter sp. by 16S rRNA gene sequencing. There were four types of co-cultures: Neocallimastix with Methanobrevibacter ruminantium, Orpinomyces with M. ruminantium, Orpinomyces with Methanobrevibacter millerae and Piromyces with M. ruminantium among 20 co-cultures. In vitro studies with wheat straw as substrate showed that the Neocallimastix with M. ruminantium co-cultures and Piromyces with M. ruminantium co-cultures exhibited higher xylanase, filter paper cellulase (FPase), ferulic acid esterase, acetyl esterase activities, in vitro dry matter digestibility, gas, CH4 , acetate production, ferulic acid and p-coumaric acid releases. The Neocallimastix frontalis Yak16 with M. ruminantium co-culture presented the strongest lignocellulose degradation ability among 20 co-cultures.

CONCLUSIONS

Twenty fungus-methanogen co-cultures were obtained from the rumen of grazing yaks. The N. frontalis with M. ruminantium co-cultures were highly effective combination for developing a fermentative system that bioconverts lignocellulose to high activity fibre-degrading enzyme, CH4 and acetate.

SIGNIFICANCE AND IMPACT OF THE STUDY

The N. frontalis with M. ruminantium co-cultures from yaks grazing on the Qinghai-Tibetan Plateau present great potential in lignocellulose biodegradation industry.

[Management of early bronchopleural fistula after pneumonectomy]

OBJECTIVE

To investigate the management of early bronchopleural fistula(BPF) within one month after pneumonectomy.

METHODS

A total of 30 cases developed BPF within one month after pneumonectomy in recent 30 years were reviewed from First Hospital of Jilin University. All patients were treated by reoperation, closed drainage with or without open thoracic window, or endobronchial glue.

RESULTS

Seventeen patients were returned to the operating room for reclosure of BPF, one patients died of BPF and 16 reoperations were successful.Twelve cases were treated by closed drainage with or without followed open thoracic window. In 6 patients who were managed by closed drainage alone, 2 cases died of BPF and 4 bronchopleural fistulas closed spontaneously. In 6 patients treated with closed drainage and later with open thoracic window, one case died of BPF. One patient successfully underwent endoscopic glue to close BPF with injection three times.

CONCLUSION

Within one month postoperatively, BPF without established empyema with pus should be reoperated if the patient had enough cardiopulmonary reserve and could there fore tolerate reoperation. Contamination of pleural space is not the contraindication to reoperation. Reclosure via original thoracotomy and repair the fistula with pedicled intercostal muscle flap are convenient and efficient. Drainage with or without followed open thoracic window is appropriate for the patients with limited cardiopulmonary reserve, impaired general condition, secondary to empyema with pus, early recurred cancer, or some small fistulas.

Direct molecular typing of Bordetella pertussis from nasopharyngeal specimens in China in 2012-2013

Data on the molecular epidemiology of Bordetella pertussis are limited in developing countries where whole-cell pertussis vaccines (WCVs) have been used. The aim of this study was to determine the genotypes of circulating B. pertussis in China by direct molecular typing of clinical specimens. DNA extracts of 122 nasopharyngeal swabs (NPs) positive for B. pertussis by polymerase chain reaction (PCR) (targeting IS481 and ptx-Pr) from 2012 to 2013 were used for typing using the multiple-locus variable number tandem repeat analysis (MLVA) and also by PCR-based multilocus sequence typing (MLST) of B. pertussis virulence genes (ptxP, prn, and fim3). One hundred and eight DNA extracts (89 %) generated a complete MLVA type (MT). Among the 18 MTs obtained, MT55 (52 %) and MT104 (13 %) were the most common. MT27, which is linked to the ptxP3 allele and is prevalent in many developed countries using acellular pertussis vaccines (ACVs), was only found in 7 (6 %) DNA extracts. Eighty-seven DNA extracts (71 %) produced a complete multiantigen sequence typing (MAST) type. Of them, 77 (89 %) had the ptxP1/prn1/fim3-1 allele profile. Four DNA extracts (5 %) had the ptxP3/prn2/fim3-2 profile and 3 (4 %) had the ptxP3/prn1/fim3-2 allele profile. These seven DNA extracts also harbored MT27. Our result shows that B. pertussis circulating in China was different from those found in countries where ACVs have been in use, supporting the notion that selection pressure induced by WCVs and ACVs on the bacterial population differs.

PAR1-stimulated platelet releasate promotes angiogenic activities of endothelial progenitor cells more potently than PAR4-stimulated platelet releasate

BACKGROUND

Endothelial progenitor cells (EPCs) are important for endothelial regeneration and angiogenesis. Thrombin protease-activated receptor 1 (PAR1) PAR1 and PAR4 stimulation induces selective release of platelet proangiogenic and antiangiogenic regulators.

OBJECTIVE

To investigate if PAR1-stimulated platelet releasate (PAR1-PR) and PAR4-PR regulate angiogenic properties of EPCs in different manners.

METHODS AND RESULTS

EPCs were generated from peripheral mononuclear cell culture. Washed platelets (2 × 10(9) mL(-1)) were stimulated by PAR1-activating peptide (PAR1-AP; 10 μmol L(-1)) or PAR4-AP (100 μmol L(-1)) to prepare PAR1-PR and PAR4-PR, respectively. PAR1-PR or PAR4-PR had little influence on EPC proliferation. EPC migration experiments using a modified Boyden chamber showed that both platelet releasates facilitated EPC migration. As for in vitro tube formation on Matrigel, PAR1-PR and PAR4-PR similarly enhanced capillary-like network formation of EPCs in the complete EPC medium containing 10% FBS and a cocktail of growth factors, while PAR1-PR more profoundly increased EPC tube formation in basal culture medium supplemented with only 0.5% FBS than did PAR4-PR. The latter was confirmed in the murine angiogenesis model of subcutaneous Matrigel implantation. Moreover, blockade of vascular endothelial growth factor, stromal cell-derived factor 1α, or matrix metalloproteinases attenuated EPC migration and tube formation, suggesting a cooperation of these factors in the enhancements.

CONCLUSIONS

PAR1-PR enhances vasculogenesis more potently than PAR4-PR, and the enhancements require a cooperation of multiple platelet-derived angiogenic regulators.

Novel NPHS1 splice site mutations in a Chinese child with congenital nephrotic syndrome

Congenital nephrotic syndrome (CNS) is defined as heavy proteinuria or nephrotic syndrome occurring before 3 months of age. It is characterized by early onset and progresses to end-stage renal disease. Recently, several genes associated with CNS have been identified, including NPHS1 and NPHS2. Mutations in the NPHS1 gene have been identified in patients with CNS in Finland with relatively high frequency. Thus far, only a few case reports about CNS have described an NPHS1 mutation in China. In this study, mutational analyses of NPHS1 and NPHS2 were performed in a Chinese child with CNS. Mutations were analyzed in all exons and exon/intron boundaries of NPHS1 and NPHS2 in the patient and his parents as well as in 50 unrelated controls using polymerase chain reaction and direct sequencing techniques. No mutations were detected in NPHS2. A novel splice site mutation (IVS11+1G>A) within intron 11 and a missense mutation within exon 8 (c.928G>A) in the NPHS1 gene were detected in the child. The child's mother had normal urinalysis and a c.928G>A (D310N) heterozygous mutation, and his father had normal urinalysis and IVS11+1G>A. These were not identified in the 50 unrelated controls. The novel splice site mutation of IVS11+1G>A and a missense mutation at c.928G>A in NPHS1 were found to cause CNS in this Chinese child.

Monocytic myeloid-derived suppressor cells accumulate in renal transplant patients and mediate CD4(+) Foxp3(+) Treg expansion

Myeloid-derived suppressor cells (MDSC) are negative regulators of the immune response and are in part responsible for the inhibition of the T cell-mediated immune responses. While MDSC have been demonstrated to participate in the induction of prolonged allograft survival in animal models of transplantation, little is known about their immune regulatory function in human transplant recipients. Here, we report that two subsets of human MDSC expressing CD11b(+), CD33(+) and HLA-DR(-) develop in renal patients posttransplantation. We found that CD14(+) expressing monocytic MDSC isolated from transplant recipients were highly efficient in suppressing the proliferation of CD4(+) T cells in mixed leukocyte reactions. In addition, we observed that CD11b(+) CD33(+) HLA-DR(-) MDSC are capable of expanding Treg in vitro, and their accumulation overtime after transplantation linearly correlated with an increase in Treg in vivo. This is the first study to link the presence of MDSC with the emergence of Treg in vivo in transplant recipients, and to define the subpopulation of MDSC derived from transplant recipients responsible for generation of Treg. Further studies are necessary to determine the alloimmune regulatory function of MDSC in human transplant recipients.

Functionalized mesoporous silica particles for application in drug delivery system

In these years, ordered mesoporous silica materials have shown promising applications in drug delivery system as drug carriers. These carriers with stable mesoporous structure, large surface area, good biocompatibility and tailored size of mesopores exhibit significant property of higher drug loading. However, silica-based mesoporous materials cannot control the release of the loaded drug without modifications. In this paper, we review the recent research work discussing functionalization of mesoporous materials by various components and methods for application in drug delivery systems. All the examples show that these functionalized mesoporous silica-based systems have great potential for a variety of drug delivery applications, specifically in the fields of the drug targeted and controlled delivery systems.

Potential role of soluble B7-H3 in liver immunopathogenesis during chronic HBV infection

Immune-mediated mechanisms have been implicated in liver pathogenesis and subsequent progression in hepatitis B virus (HBV) infection. Costimulatory molecules, the important regulators of immune responses, participate in the regulation of liver pathology in HBV infection. However, the role of B7-H3 (CD276, a new member of B7 family) in this process has not been investigated. In this study, we detected abundant soluble B7-H3 (sB7-H3) in the plasma of patients with chronic HBV infections. The increase of the plasma B7-H3 was associated with the progression of liver cirrhosis and accompanied by decreased expression of B7-H3 on hepatocytes. The identification analysis suggests that the plasma B7-H3 might be derived from the membrane-bound B7-H3 on hepatocytes. A functional study showed that immobilized (4Ig) B7-H3Ig fusion protein could inhibit TCR-induced proliferation and IFN-γ secretion of T cells, which could be partially blocked by soluble B7-H3flag fusion protein. These results suggest that the reduced expression of B7-H3 in the livers might temper the inhibition of T-cell responses mediated by B7-H3 expressed on hepatocytes and thus promote the hepatic inflammation and hepatitis progression in the chronic HBV-infected patients.

Immune reconstitution following rabbit antithymocyte globulin

Depletional induction therapies are routinely used to prevent acute rejection and improve transplant outcome. The effects of depleting agents on T-cell subsets and subsequent T-cell reconstitution are incompletely defined. We used flow cytometry to examine the effects of rabbit antithymocyte globulin (rATG) on the peripheral T-cell repertoire of pediatric and adult renal transplant recipients. We found that while rATG effectively depleted CD45RA+CD27+ naïve and CD45RO+CD27+ central memory CD4+ T cells, it had little effect on CD45RO+CD27- CD4+ effector memory or CD45RA+CD31-, CD45RO+CD27+ and CD45RO+CD27- CD8+ T cell subsets. When we performed a kinetic analysis of CD31+ recent thymic emigrants and CD45RA+/RO+ T cells, we found evidence for both thymopoiesis and homeostatic proliferation contributing to immune reconstitution. We additionally examined the impact of rATG on peripheral CD4+Foxp3+ T cells. We found that in adults, administration of rATG-induced peripheral expansion and new thymic emigration of T cells with a Treg phenotype, while CD4+Foxp3+ T cells of thymic origin predominated in children, providing the first evidence that rATG induces Treg in vivo. Collectively our data indicate that rATG alters the balance of regulatory to memory effector T cells posttransplant, providing an explanation for how it positively impacts transplant outcome.

Prioritisation of associations between protein domains and complex diseases using domain-domain interaction networks

It is of vital importance to find genetic variants that underlie human complex diseases and locate genes that are responsible for these diseases. Since proteins are typically composed of several structural domains, it is reasonable to assume that harmful genetic variants may alter structures of protein domains, affect functions of proteins and eventually cause disorders. With this understanding, the authors explore the possibility of recovering associations between protein domains and complex diseases. The authors define associations between protein domains and disease families on the basis of associations between non-synonymous single nucleotide polymorphisms (nsSNPs) and complex diseases, similarities between diseases, and relations between proteins and domains. Based on a domain-domain interaction network, the authors propose a 'guilt-by-proximity' principle to rank candidate domains according to their average distance to a set of seed domains in the domain-domain interaction network. The authors validate the method through large-scale cross-validation experiments on simulated linkage intervals, random controls and the whole genome. Results show that areas under receiver operating characteristic curves (AUC scores) can be as high as 77.90%, and the mean rank ratios can be as low as 21.82%. The authors further offer a freely accessible web interface for a genome-wide landscape of associations between domains and disease families.

Regulation of chondrocyte differentiation by ADAMTS-12 metalloproteinase depends on its enzymatic activity

ADAMTS-12, a metalloproteinase that belongs to ADAMTS family, is strongly upregulated during chondrogenesis and demonstrates prominent expression in the growth plate chondrocytes. ADAMTS-12 potently inhibits chondrocyte differentiation, as revealed by altered expression of both early and later genes critical for chondrogenesis. In addition, ADAMTS-12-mediated inhibition of chondrogenesis depends on its enzymatic activity, since its point mutant lacking enzymatic activity completely loses this activity. Furthermore, the C-terminal four thrombospondin motifs known to bind COMP substrate is necessary for its full proteolytic activity and inhibition of chondrocyte differentiation. Mechanism studies demonstrate that ADAMTS-12 induces PTHrP, whereas it inhibits IHH during chondrogenesis. Furthermore, PTHrP induces ADAMTS-12 and ADAMTS-12 is hardly detectable in PTHrP-/-growth plate chondrocytes. Importantly, knocking down ADAMTS-12 mRNA levels or blocking ADAMTS-12 activity almost abolishes the PTHrP-mediated inhibition of type X collagen expression. Collectively, these findings demonstrate that ADAMTS-12, a downstream molecule of PTHrP signaling, is a novel regulator of chondrogenesis.

Inhibition of ADAMTS-7 and ADAMTS-12 degradation of cartilage oligomeric matrix protein by alpha-2-macroglobulin

OBJECTIVE

As we previously reported, ADAMTS-7 and ADAMTS-12, two members of ADAMTS (a disintegrin and metalloprotease with thrombospondin motifs) family, degrade cartilage oligomeric matrix protein (COMP) in vitro and are significantly induced in the cartilage and synovium of arthritic patients [Liu CJ, Kong W, Ilalov K, Yu S, Xu K, Prazak L, et al. ADAMTS-7: a metalloproteinase that directly binds to and degrades cartilage oligomeric matrix protein. FASEB J 2006;20(7):988-90; Liu CJ, Kong W, Xu K, Luan Y, Ilalov K, Sehgal B, et al. ADAMTS-12 associates with and degrades cartilage oligomeric matrix protein. J Biol Chem 2006;281(23):15800-8]. The purpose of this study was to determine (1) whether cleavage activity of ADAMTS-7 and ADAMTS-12 of COMP are associated with COMP degradation in osteoarthritis (OA); (2) whether alpha-2-macroglobulin (a(2)M) is a novel substrate for ADAMTS-7 and ADAMTS-12; and (3) whether a(2)M inhibits ADAMTS-7 or ADAMTS-12 cleavage of COMP.

METHODS

An in vitro digestion assay was used to examine the degradation of COMP by ADAMTS-7 and ADAMTS-12 in the cartilage of OA patients; in cartilage explants incubated with tumor necrosis factor-alpha (TNF-alpha) or interleukin-1-beta (IL-1beta) with or without blocking antibodies; and in human chondrocytes treated with specific small interfering RNA (siRNA) to knockdown ADAMTS-7 or/and ADAMTS-12. Digestion of a(2)M by ADAMTS-7 and ADAMTS-12 in vitro and the inhibition of ADAMTS-7 or ADAMTS-12-mediated digestion of COMP by a(2)M were also analyzed.

RESULTS

The molecular mass of the COMP fragments produced by either ADAMTS-7 or ADAMTS-12 were similar to those observed in OA patients. Specific blocking antibodies against ADAMTS-7 and ADAMTS-12 dramatically inhibited TNF-alpha- or IL-1beta-induced COMP degradation in the cultured cartilage explants. The suppression of ADAMTS-7 or ADAMTS-12 expression by siRNA silencing in the human chondrocytes also prevented TNF-alpha- or IL-1beta-induced COMP degradation. Both ADAMTS-7 and ADAMTS-12 were able to cleave a(2)M, giving rise to 180- and 105-kDa cleavage products, respectively. Furthermore, a(2)M inhibited both ADAMTS-7- and ADAMTS-12-mediated COMP degradation in a concentration (or dose)-dependent manner.

CONCLUSION

Our observations demonstrate the importance of COMP degradation by ADAMTS-7 and ADAMTS-12 in vivo. Furthermore, a(2)M is a novel substrate for ADAMTS-7 and ADAMTS-12. More significantly, a(2)M represents the first endogenous inhibitor of ADAMTS-7 and ADAMTS-12.

Transient binding and dissipation in cross-linked actin networks

In contrast with entangled actin solutions, transiently cross-linked actin networks can provide highly elastic properties while still allowing for local rearrangements in the microstructure-on biological relevant time scales. Here, we show that thermal unbinding of transient cross-links entails local stress relaxation and energy dissipation in an intermediate elasticity dominated frequency regime. We quantify the viscoelastic response of an isotropically cross-linked actin network by experimentally tuning the off rate of the transiently cross-linking molecules, their density, and the solvent viscosity. We reproduce the measured frequency response by a semiphenomenological model that is predicated on microscopic unbinding events.

The relationship between endothelial dysfunction and oxidative stress in diabetes and prediabetes

OBJECTIVE

Diabetes mellitus is associated with endothelial dysfunction and oxidative stress (OS). The aim of the present study was to determine whether increased OS and impaired endothelial function, are present in early states of diabetes, such as impaired glucose tolerance (IGT) and impaired fasting glucose (IFG).

METHODS

Brachial artery flow-mediated dilatation (FMD) and nitrate-induced dilatation were measured in 133 subjects with carbohydrate abnormalities (45 IGT, 44 IFG and 44 Type 2 diabetes mellitus) and in 46 subjects with normal glucose tolerance (NGT). Waist circumference, body mass index, blood pressure and fasting lipid profiles were obtained, and glucose and insulin values in response to a 75-g oral glucose load were also measured. Plasma malondialdehyde (MDA) and superoxide dismutase (SOD) activity were determined.

RESULTS

Patients with diabetes and prediabetes had a higher plasma MDA concentration, but a lower plasma SOD activity than the NGT group (p = 0.006) and SOD activity was positively associated with FMD (p = 0.039). FMD were significantly reduced in the groups of subjects with abnormal carbohydrate metabolism compared with the NGT group (p = 0.035). Among the subjects with diabetes and prediabetes, FMD showed a negative correlation with fasting glucose and/or plasma glucose level at 120 min after oral glucose tolerance test (p = 0.028).

CONCLUSIONS

The results showed that endothelial dysfunction and increased OS were present in subjects with IGT and IFG, indicating endothelial damage in these stages.

Model-based methods for identifying periodically expressed genes based on time course microarray gene expression data

MOTIVATION

The expressions of many genes associated with certain periodic biological and cell cycle processes such as circadian rhythm regulation are known to be rhythmic. Identification of the genes whose time course expressions are synchronized to certain periodic biological process may help to elucidate the molecular basis of many diseases, and these gene products may in turn represent drug targets relevant to those diseases.

RESULTS

We propose in this paper a statistical framework based on a shape-invariant model together with a false discovery rate (FDR) procedure for identifying periodically expressed genes based on microarray time-course gene expression data and a set of known periodically expressed guide genes. We applied the proposed methods to the alpha-factor, cdc15 and cdc28 synchronized yeast cell cycle data sets and identified a total of 1010 cell-cycle-regulated genes at a FDR of 0.5% in at least one of the three data sets analyzed, including 89 (86%) of 104 known periodic transcripts. We also identified 344 and 201 circadian rhythmic genes in vivo in mouse heart and liver tissues with FDR of 10 and 2.5%, respectively. Our results also indicate that the shape-invariant model fits the data well and provides estimate of the common shape function and the relative phases for these periodically regulated genes.

Quantitative determination of nitrendipine and its metabolite dehydronitrendipine in human plasma using liquid chromatography-tandem mass spectrometry

A sensitive and high-throughput LC-MS-MS method was developed for simultaneous determination of nitrendipine (NIT) and its major metabolite, dehydronitrendipine (DNIT) in human plasma using nifedipine as the internal standard. Plasma samples were prepared based on a simple liquid-liquid extraction. The extracted samples were analyzed on a Zorbax SB C(18) column interfaced with a triple quadrupole tandem mass spectrometer. Positive atmospheric pressure chemical ionization was employed as the ionization source. The analytes were detected by use of selected reaction monitoring mode. Standard curves were linear (r > or = 0.995) over the concentration range of 0.4-40 ng/mL for NIT and 0.2-20 ng/mL for DNIT. The intra- and inter-run precision was measured to be below 8.5% for NIT and DNIT. The inter-run accuracy was less than 4% for the analytes. The overall extraction recoveries of NIT and DNIT were determined to be about 75% and 78% on average, respectively. The chromatographic run time was approximately 3 min. More than 120 samples could be assayed daily with this method, including sample preparation, data acquisition and processing. The method developed was successfully used to investigate plasma concentrations of NIT and DNIT in a pharmacokinetic study of volunteers who received NIT orally.