We report the discovery of two long-wavelength (365 nm) photoactivatable diaryltetrazoles through screening a small library of diaryltetrazoles that were designed using a ‘scaffold hopping’ strategy. A naphthalene-derived tetrazole showed excellent reactivity in the photoinduced cycloaddition reaction with methyl methacrylate under 365-nm photoirradiation in PBS buffer. Besides, the brightly fluorescent pyrazoline cycloadducts that were formed further increase the potential utility of these new diaryltetrazoles as “photoclick” reagents and as reporters in biological studies.
bioorthogonal chemistry; photoclick chemistry; dipolar cycloaddition; tetrazoles; fluorophores
Three p160 family members, p/CIP, SRC1, and TIF2, have been identified as transcriptional coactivators for nuclear hormone receptors and other transcription factors in vitro. In a previous study, we reported initial characterization of the obesity-resistant phenotypes of p/CIP and SRC-1 double knockout (DKO) mice, which exhibit increased energy expenditure, and suggested that nuclear hormone receptor target genes were involved in these phenotypes. In this study, we demonstrate that p/CIP and SRC1 control insulin signaling in a cell-autonomous manner both in vitro and in vivo. Genetic deletion of p/CIP and SRC-1 increases glucose uptake and enhances insulin sensitivity in both regular chow- and high fat diet-fed DKO mice despite increased food intake. Interestingly, we discover that loss of p/CIP and SRC-1 results in resistance to age-related obesity and glucose intolerance. We show that expression levels of a key insulin signaling component, insulin receptor substrate 1 (IRS1), are significantly increased in two cell lines representing fat and muscle lineages with p/CIP and SRC-1 deletions and in white adipose tissue and skeletal muscle of DKO mice; this may account for increased glucose metabolism and insulin sensitivity. This is the first evidence that the p160 coactivators control insulin signaling and glucose metabolism through IRS1. Therefore, our studies indicate that p/CIP and SRC-1 are potential therapeutic targets not only for obesity but also for diabetes.
The prevalence of childhood obesity among adolescents has been rapidly rising in Mainland China in recent decades, especially in urban and rich areas. There is an urgent need to develop effective interventions to prevent childhood obesity. Limited data regarding adolescent overweight prevention in China are available. Thus, we developed a school-based intervention with the aim of reducing excess body weight in children. This report described the study design.
We designed a cluster randomized controlled trial in 8 randomly selected urban primary schools between May 2010 and December 2013. Each school was randomly assigned to either the intervention or control group (four schools in each group). Participants were the 4th graders in each participating school. The multi-component program was implemented within the intervention group, while students in the control group followed their usual health and physical education curriculum with no additional intervention program. The intervention consisted of four components: a) classroom curriculum, (including physical education and healthy diet education), b) school environment support, c) family involvement, and d) fun programs/events. The primary study outcome was body composition, and secondary outcomes were behaviour and behavioural determinants.
The intervention was designed with due consideration of Chinese cultural and familial tradition, social convention, and current primary education and exam system in Mainland China. We did our best to gain good support from educational authorities, school administrators, teachers and parents, and to integrate intervention components into schools’ regular academic programs. The results of and lesson learned from this study will help guide future school-based childhood obesity prevention programs in Mainland China.
Registration number: ChiCTR-ERC-11001819
Hexokinase (HK), the rate-limiting enzyme in glycolysis, regulates cell survival either by promoting metabolism and/or inhibiting apoptosis. HKI and HKII, isoforms with mitochondrial targeting sequences, were studied in renal epithelial cells after ATP depletion, an insult that activates GSK3β and Bax, induces mitochondrial membrane injury and causes apoptosis. Stress decreased total ATP content, caused HKII to dissociate from mitochondria, released mitochondrial apoptosis inducing factor (AIF) and cytochrome c, activated caspase-3 and reduced cell survival. Compared to control, HKI or II over-expression improved survival after stress without preventing GSK3β or Bax activation, increasing ATP content, or reducing mitochondrial fragmentation. HKI or HKII over-expression increased mitochondria-associated, isoform-specific HK content and decreased mitochondrial membrane injury and apoptosis. In vivo, HKII localized to the murine proximal tubule. Ischemia reduced total HKII content and caused mitochondrial HKII dissociation in proximal but not distal tubules. In HK over-expressing cells, HKII and Bax did not interact before or after stress. However, HK over-expression increased organelle-associated HK during stress and decreased mitochondrial Bax accumulation, outer membrane injury and apoptosis in a manner that appears to be independent of its effect on renal epithelial cell ATP content, suggesting that HK and Bax compete for similar mitochondrial membrane binding sites.
acute kidney injury; apoptosis; proximal tubule; renal ischemia-reperfuison
Compared with the protein 3-class secondary structure (SS) prediction, the 8-class prediction gains less attention and is also much more challenging, especially for proteins with few sequence homologs. This paper presents a new probabilistic method for 8-class SS prediction using conditional neural fields (CNFs), a recently invented probabilistic graphical model. This CNF method not only models the complex relationship between sequence features and SS, but also exploits the interdependency among SS types of adjacent residues. In addition to sequence profiles, our method also makes use of non-evolutionary information for SS prediction. Tested on the CB513 and RS126 data sets, our method achieves Q8 accuracy of 64.9 and 64.7%, respectively, which are much better than the SSpro8 web server (51.0 and 48.0%, respectively). Our method can also be used to predict other structure properties (e.g. solvent accessibility) of a protein or the SS of RNA.
Bioinformatics; Conditional neural fields; Eight class; Protein; Secondary structure prediction
OSCC is one of the most common malignancies and numerous clinical agents currently applied in combinative chemotherapy. Here we reported a novel therapeutic strategy, SAHA and DDP-loaded PECE (SAHA-DDP/PECE), can improve the therapeutic effects of intratumorally chemotherapy on OSCC cell xenografts.
The objective of this study was to evaluate the therapeutic efficacy of the SAHA-DDP/PECE in situ controlled drug delivery system on OSCC cell xenografts.
A biodegradable and thermosensitive hydrogel was successfully developed to load SAHA and DDP. Tumor-beared mice were intratumorally administered with SAHA-DDP/PECE at 50 mg/kg (SAHA) +2 mg/kg (DDP) in 100 ul PECE hydrogel every two weeks, SAHA-DDP at 50 mg/kg(SAHA) +2 mg/kg(DDP) in NS, 2 mg/kg DDP solution, 50 mg/kg SAHA solution, equal volume of PECE hydrogel, or equal volume of NS on the same schedule, respectively. The antineoplastic actions of SAHA and DDP alone and in combination were evaluated using the determination of tumor volume, immunohistochemistry, western blot, and TUNEL analysis.
The hydrogel system was a free-flowing sol at 10°C, become gel at body temperature, and could sustain more than 14 days in situ. SAHA-DDP/PECE was subsequently injected into tumor OSCC tumor-beared mice. The results demonstrated that such a strategy as this allows the carrier system to show a sustained release of SAHA and DDP in vivo, and could improved therapeutic effects compared with a simple additive therapeutic effect of SAHA and DDP on mouse model.
Our research indicated that the novel SAHA-DDP/PECE system based on biodegradable PECE copolymer enhanced the therapeutic effects and could diminished the side effects of SAHA/DDP. The present work might be of great importance to the further exploration of the potential application of SAHA/DDP-hydrogel controlled drug release system in the treatment of OSCC.
The role of mitofusin 2 (MFN2), a key regulator of mitochondrial morphology and function in the renal stress response is unknown. To assess its role, the MFN2 floxed gene was conditionally deleted in the kidney of mice (MFN2 cKO) by Pax2 promoter driven Cre expression (Pax2Cre). MFN2 cKO caused severe mitochondrial fragmentation in renal epithelial cells that are critical for normal kidney tubular function. However, despite a small (20%) decrease in nephron number, newborn cKO pups had organ or tubular function that did not differ from littermate Cre-negative pups. MFN2 deficiency in proximal tubule epithelial cells in primary culture induced mitochondrial fragmentation but did not significantly alter ATP turnover, maximal mitochondrial oxidative reserve capacity, or the low level of oxygen consumption during cyanide exposure. MFN2 deficiency also did not increase apoptosis of tubule epithelial cells under non-stress conditions. In contrast, metabolic stress caused by ATP depletion exacerbated mitochondrial outer membrane injury and increased apoptosis by 80% in MFN2 deficient vs. control cells. Despite similar stress-induced Bax 6A7 epitope exposure in MFN2 deficient and control cells, MFN2 deficiency significantly increased mitochondrial Bax accumulation and was associated with greater release of both apoptosis inducing factor and cytochrome c. In conclusion, MFN2 deficiency in the kidney causes mitochondrial fragmentation but does not affect kidney or tubular function during development or under non-stress conditions. However, MFN2 deficiency exacerbates renal epithelial cell injury by promoting Bax-mediated mitochondrial outer membrane injury and apoptosis.
Successful treatment of cancer with dendritic cell tumor vaccine is highly dependent on how effectively the vaccine migrates into lymph nodes and activates T cells. In this study, a simple method was developed to trace migration of dendritic cells to lymph nodes.
Superparamagnetic iron oxide (SPIO) of γ-Fe2O3 nanoparticles were prepared to label dendritic cells generated from bone marrow of enhanced green fluorescent protein (EGFP) transgenic mice, to explore the fluorescence intensity of EGFP influenced by the SPIO, and to make images of labeled dendritic cells with the help of magnetic resonance imaging in vitro. The SPIO-EGFP-labeled dendritic cells were injected into the footpads of five mice. After 48 hours, magnetic resonance imaging, optical imaging, confocal imaging, and Prussian blue staining were used to confirm migration of the SPIO-EGFP-labeled dendritic cells into draining lymph nodes.
The synthetic SPIO nanoparticles had a spherical shape and desirable superparamagnetism, and confocal imaging and Prussian blue staining showed perfect labeling efficiency as well. Furthermore, the dendritic cells dual-labeled by SPIO and EGFP could migrate into lymph nodes after footpad injection, and could be detected by both magnetic resonance imaging and optical imaging simultaneously, which was further confirmed by immunohistochemistry and Prussian blue staining. The percentage of dendritic cells migrated to the draining lymph nodes was about 4%.
Synthetic SPIO nanoparticles are strong contrast agents with good biocompatibility, and EGFP transgenic dendritic cells can be labeled efficiently by SPIO, which are suitable for further study of the migratory behavior and biodistribution of dendritic cells in vivo.
magnetic resonance imaging; optical imaging; dendritic cell; superparamagnetic iron oxide; cell tracking
Genistein, one of the major isoflavones, has received great attention as a phytoestrogen and potential cancer chemoprevention agent. However, the dissolution and bioavailability of genistein from solid oral preparations is low due to its poor water solubility.
In order to improve the oral bioavailability of genistein, genistein nanoparticles were prepared by the nanoprecipitation technique using Eudragit® E100 as carriers and an optimized formulation of mass ratio (genistein:Eudragit E100, 1:10). The mean particle size of genistein nanoparticles was approximately 120 nm when diluted 100 times with distilled water. The drug-loaded nanoparticles were spherical on observation by transmission electric microscopy.
Encapsulation efficiency and drug loading of the genistein nanoparticles were approximately 50.61% and 5.02%, respectively. Release of drug from the genistein nanoparticles was two times greater than that from the conventional capsules. After administration of genistein suspension or genistein nanoparticles at a single dose of 100 mg/kg to fasted rats, the relative bioavailability of genistein from the nanoparticles compared with the reference suspension was 241.8%.
These results suggested that a nanoparticle system is a potentially promising formulation for the efficient delivery of poorly water-soluble drugs by oral administration.
bioavailability; dissolution; genistein; nanoparticles; nanoprecipitation technique
The neuropeptide, calcitonin gene-related peptide (CGRP) has been proposed to be a regulator of the development of morphine analgesic tolerance and thereby could be a target to reduce the induction of this phenomenon under clinical conditions. However, the mechanisms of CGRP regulation are unclear. We investigated here the possible role of the extracellular signal-regulated protein kinase (ERK), p38 and calcium/calmodulin-dependent protein kinase II (CaMKII) in CGRP regulation following chronic morphine treatment.
A 7-day treatment with morphine (15 μg/day) led to an increase in CGRP contents in the spinal cord dorsal horn (SCDH) and dorsal root ganglion (DRG) and this effect was prevented by the inhibition of the ERK, p38 or CaMKII pathway. The phosphorylation/activation of ERK, p38 and CaMKII was enhanced in the SCDH following chronic morphine while in DRG only the phosphorylation of CaMKII was increased. Moreover, our chronic morphine treatment up-regulated neuronal nitric oxide synthase (nNOS) levels in the SCDH, an effect blocked by the inhibition of the ERK, p38 or CaMKII pathway. The blockade of nNOS activity also suppressed chronic morphine-induced CGRP increases in the DRG and SCDH. Double immunofluorescence studies revealed that nNOS and CaMKII are co-localized in the SCDH and that CaMKII is activated in CGRP-expressing DRG neurons.
The activation of spinal ERK, p38 and CaMKII, alongside nNOS, is involved in chronic morphine-induced CGRP up-regulation in both the DRG and SCDH. Moreover, the stimulation of CaMKII in the DRG likely directly regulates the expression of CGRP associated with morphine analgesic tolerance.
CGRP; ERK; p38; CaMKII; morphine
We present a label-free, chemically-selective, quantitative imaging strategy to identify breast cancer and differentiate its subtypes using coherent anti-Stokes Raman scattering (CARS) microscopy. Human normal breast tissue, benign proliferative, as well as in situ and invasive carcinomas, were imaged ex vivo. Simply by visualizing cellular and tissue features appearing on CARS images, cancerous lesions can be readily separated from normal tissue and benign proliferative lesion. To further distinguish cancer subtypes, quantitative disease-related features, describing the geometry and distribution of cancer cell nuclei, were extracted and applied to a computerized classification system. The results show that in situ carcinoma was successfully distinguished from invasive carcinoma, while invasive ductal carcinoma (IDC) and invasive lobular carcinoma were also distinguished from each other. Furthermore, 80% of intermediate-grade IDC and 85% of high-grade IDC were correctly distinguished from each other. The proposed quantitative CARS imaging method has the potential to enable rapid diagnosis of breast cancer.
(170.3880) Medical and biological imaging; (170.4580) Optical diagnostics for medicine; (180.4315) Nonlinear microscopy; (300.6230) Spectroscopy, coherent anti-Stokes Raman scattering microscopy
Accurate tertiary structures are very important for the functional study of non-coding RNA molecules. However, predicting RNA tertiary structures is extremely challenging, because of a large conformation space to be explored and lack of an accurate scoring function differentiating the native structure from decoys. The fragment-based conformation sampling method (e.g. FARNA) bears shortcomings that the limited size of a fragment library makes it infeasible to represent all possible conformations well. A recent dynamic Bayesian network method, BARNACLE, overcomes the issue of fragment assembly. In addition, neither of these methods makes use of sequence information in sampling conformations. Here, we present a new probabilistic graphical model, conditional random fields (CRFs), to model RNA sequence–structure relationship, which enables us to accurately estimate the probability of an RNA conformation from sequence. Coupled with a novel tree-guided sampling scheme, our CRF model is then applied to RNA conformation sampling. Experimental results show that our CRF method can model RNA sequence–structure relationship well and sequence information is important for conformation sampling. Our method, named as TreeFolder, generates a much higher percentage of native-like decoys than FARNA and BARNACLE, although we use the same simple energy function as BARNACLE.
Contact: firstname.lastname@example.org; email@example.com
Supplementary Information: Supplementary data are available at Bioinformatics online.
A custom built coherent anti-Stokes Raman scattering (CARS) microscope was used to image prostatic glands and nerve structures from 17 patients undergoing radical prostatectomy. Imaging of glandular and nerve structures showed distinctive cellular features that correlated to histological stains. Segmentation of cell nucleus was performed to establish a cell feature-based model to separate normal glands from cancer glands. In this study, we use a single parameter, average cell neighbor distance based on CARS imaging, to characterize normal and cancerous glandular structures. By combining CARS with our novel classification model, we are able to characterize prostate glandular and nerve structures in a manner that potentially enables real-time, intra-operative assessment of surgical margins and neurovascular bundles. As such, this method could potentially improve outcomes following radical prostatectomy.
(180.4315) Nonlinear microscopy; (170.1610) Clinical applications; (170.3880) Medical and biological imaging; (170.4580) Optical diagnostics for medicine
In the context of recent social and economic transitions in China, lack of physical activity among adolescents is an emerging health risk, particularly so in rapidly expanding urban areas. Evidence from Western countries suggests that built environment attributes can influence the physical activity participation of young people, but whether or not this is the case for China is unknown. We recruited high school students from ten urban districts in Nanjing, Mainland China (n = 2,375; mean age = 13.9 ± 1.0 years old; 46% boys; survey response rate = 89%). The outcome variable was self-reported recreational physical activity time; the primary explanatory variable was the residential density of the urban districts. Analysis was conducted using mixed-effects logistic regression models. After adjustment for potential confounding variables, including sedentary behavior and green space, there was a consistent and graduated association between residential density and physical activity; residential density was significantly negatively associated with recreational physical activity time for students from the higher tertile of residential density (OR; 95% CI = 0.64; 0.42 to 0.97) compared to those from the lower tertile. The direction and magnitude of the negative association between residential density and physical activity was similar for boys and girls. It should be a public health priority to identify the particular urban environment attributes that can encourage and support young people’s participation in physical activity.
Built environment; Residential density; Physical activity; Sedentary behavior; Adolescents; China
An nm-thickness composite gold thin film consisting of gold nanoparticles and polyelectrolytes is fabricated through ionic self-assembled multilayers (ISAM) technique and is deposited on end-faces of optical fibers to construct localized surface plasmon resonance (LSPR) fiber probes. We demonstrate that the LSPR spectrum induced by ISAM gold films can be fine-tuned through the ISAM procedure. We investigate variations of reflection spectra of the probe with respect to the layer-by-layer adsorption of ISAMs onto end-faces of fibers, and study the spectral variation mechanism. Finally, we demonstrated using this fiber probe to detect the biotin-streptavidin bioconjugate pair. ISAM adsorbed on optical fibers potentially provides a simple, fast, robust, and low-cost, platform for LSPR biosensing applications.
localized surface plasmon resonance; ionic self-assembled multilayers; fiber optics; biosensors
An inverse relationship between physical activity (PA) and depression among adolescents has been reported in developed communities without consideration of sedentary behaviors (SB, including sitting for course study, viewing TV, and sleeping). We explored the association between recreational PA time (hr/wk) and depression after adjustment with SB and other possible confounders among Chinese adolescents.
A population-based cross-sectional study was conducted in Nanjing municipality of China in 2004 using a multi-stage cluster sampling approach. A total of 72 classes were randomly selected from 24 urban junior high schools and all students completed the structured questionnaire. Adolescent depression was examined by the Children's Depression Inventory (CDI) of Chinese version with cutoff point value of 20 or above as the presence of depression. Recreational PA time was measured by a question on weekly hours of PA outside of school. Descriptive statistics, multivariate logistic and linear regression models were used in analysis.
The overall prevalence of depression was 15.7% (95%CI: 14.3%, 17.1%) among 2,444 eligible participants. It was found that physical activity was negatively associated with depression. After adjustment for sedentary behaviors and other potential confounders, participants who spent 1–7 hr/wk, 8–14 hr/wk and 15+ hr/wk for recreational PA, respectively, had odds ratios of 0.70 (95% CI = 0.57, 0.86), 0.68 (95% CI = 0.53, 0.88) and 0.66 (95% CI = 0.50, 0.87) for likelihood of being depressive, compared to their counterparts who spent 0–0.9 hr/wk for PA. This inverse relationship between PA time and depression remained statistically significant by gender and grade.
This study, conducted among Chinese adolescents, strengthened the evidence that physical activity was inversely associated with depression. Our study has important implications for health officers and public health professionals to pay much attention to the relationship between physical activity and depression in Mainland China.
Plant hormones are small organic molecules that influence almost every aspect of plant growth and development. Genetic and molecular studies have revealed a large number of genes that are involved in responses to numerous plant hormones, including auxin, gibberellin, cytokinin, abscisic acid, ethylene, jasmonic acid, salicylic acid, and brassinosteroid. Here, we develop an Arabidopsis hormone database, which aims to provide a systematic and comprehensive view of genes participating in plant hormonal regulation, as well as morphological phenotypes controlled by plant hormones. Based on data from mutant studies, transgenic analysis and gene ontology (GO) annotation, we have identified a total of 1026 genes in the Arabidopsis genome that participate in plant hormone functions. Meanwhile, a phenotype ontology is developed to precisely describe myriad hormone-regulated morphological processes with standardized vocabularies. A web interface (http://ahd.cbi.pku.edu.cn) would allow users to quickly get access to information about these hormone-related genes, including sequences, functional category, mutant information, phenotypic description, microarray data and linked publications. Several applications of this database in studying plant hormonal regulation and hormone cross-talk will be presented and discussed.
Inhibition of γ-aminobutyric acid aminotransferase (GABA-AT) raises the concentration of GABA, an inhibitory neurotransmitter in human brain, which could have therapeutic applications for a variety of neurological diseases including epilepsy. Based on studies of several previously synthesized conformationally-restricted GABA-AT inhibitors, (±)- (1S,2R,5S)-5-amino-2-fluorocyclohex-3-ene carboxylic acid (12) was designed as a mechanismbased inactivator. This compound was shown to irreversibly inhibit GABA-AT; substrate protects the enzyme from inactivation. Mechanistic experiments demonstrated the loss of one fluoride ion per active site during inactivation and the formation of N-m-carboxyphenylpyridoxamine 5′-phosphate (26), the same product generated by inactivation of GABA-AT by gabaculine (8). An elimination-aromatization mechanism is proposed to account for these results.
Nuclear matrix attachment regions (MARs) flanking the immunoglobulin heavy chain intronic enhancer (Eμ) are the targets of the negative regulator, NF-μNR, found in non-B and early pre-B cells. Expression library screening with NF-μNR binding sites yielded a cDNA clone encoding an alternatively spliced form of the Cux/CDP homeodomain protein. Cux/CDP fulfills criteria required for NF-μNR identity. It is expressed in non-B and early pre-B cells but not mature B cells. It binds to NF-μNR binding sites within Eμ with appropriate differential affinities. Antiserum specific for Cux/CDP recognizes a polypeptide of the predicted size in affinity-purified NF-μNR preparations and binds NF-μNR complexed with DNA. Cotransfection with Cux/CDP represses the activity of Eμ via the MAR sequences in both B and non-B cells. Cux/CDP antagonizes the effects of the Bright transcription activator at both the DNA binding and functional levels. We propose that Cux/CDP regulates cell-type-restricted, differentiation stage-specific Eμ enhancer activity by interfering with the function of nuclear matrix-bound transcription activators.