Transcriptomic Analysis on Pectoral Muscle of European Meat Pigeons and Shiqi Pigeons during Embryonic Development.

In avian muscle development, embryonic muscle development determines the number of myofibers after birth. Therefore, in this study, we investigated the phenotypic differences and the molecular mechanism of pectoral muscle development of the European meat pigeon Mimas strain (later called European meat pigeon) and Shiqi pigeon on embryonic day 6 (E6), day 10 (E10), day 14 (E14) and day 1 after birth (P1). The results showed that the myofiber density of the Shiqi pigeon was significantly higher than that of the European meat pigeon on E6, and myofibers with a diameter in the range of 50~100 µm of the Shiqi pigeon on P1 were significantly higher than those of European meat pigeon. A total of 204 differential expressed genes (DEGs) were obtained from RNA-seq analysis in comparison between pigeon breeds at the same stage. DEGs related to muscle development were found to significantly enrich the cellular amino acid catabolism, carboxylic acid catabolism, extracellular matrix receptor interaction, REDOX enzyme activity, calcium signaling pathway, ECM receptor interaction, PPAR signaling pathway and other pathways. Using Cytoscape software to create mutual mapping, we identified 33 candidate genes. RT-qPCR was performed to verify the 8 DEGs selected-DES, MYOD, MYF6, PTGS1, MYF5, MYH1, MSTN and PPARG-and the results were consistent with RNA-seq. This study provides basic data for revealing the distinct embryonic development mechanism of pectoral muscle between European meat pigeons and Shiqi pigeons.

Identification of microbes in wounds using near-infrared spectroscopy.

BACKGROUND: Rapid diagnosis of microbes in the burn wound is a big challenge in the medical field. Traditional biochemical detection techniques take hours or days to identify the species of contaminating and drug-resistant microbes. Near-infrared spectroscopy (NIRS) is evaluated to address the need for a fast and sensitive method for the detection of bacterial contamination in liquids. METHODS: Herin, we developed a novel technique which by using NIRS together with supporting vector machine (SVM), to identify the microbial species and drug-resistant microbes in LB medium, and to diagnose the wound colonization and wound infection models of pigs. RESULTS: The device could recognize 100% of seven kinds of microbes and 99.47% of the multi-drug resistant Staphylococcus aureus (S. aureus), with a concentration of 109 cfu ml-1 in LB medium. The accuracy of the microbial identification in colonized and infected wounds in-situ was 100%. The detection limit of NIRS with SVM for the detection of S. aureus and Escherichia coli (E. coli) was 101 cfu ml-1 in LB medium. Identification time was less than 5 s. CONCLUSION: Our findings validate for the first time a novel technique aimed at the rapid, noncontacted, highly sensitive, and specific recognition of several microbial species including drug-resistant ones. This technique could represent a promising approach to identify diverse microbial species and a potential bedside device to rapidly diagnose infected wounds.

Preparation of carbon dots-doped terbium phosphonate coordination polymers as ratiometric fluorescent probe for citrate detection.

In this work, carbon dots-doped terbium phosphonate coordination polymers (CDs-GMP/Tb) were designed and prepared as ratiometric fluorescent probes for the detection of citrate. The as-prepared CDs-GMP/Tb are prepared and have the merits of high photostability, low toxicity, and excellent biocompatibility. The as-prepared CDs-GMP/Tb as ratiometric fluorescent probes also have better anti-interference ability and stability compared with the traditional single fluorescent probe. The surface morphology, fabrication, and spectroscopy were characterized through a variety of instruments. It confirms that the probes exhibited network structure doping carbon dots. With the addition of citrate, the fluorescence of GMP/Tb at 545 nm was significantly quenched, contrasting to the enhancement of fluorescence of CDs at 454 nm. Under optimum conditions, the detection limit for citrate was 0.47 µM, with a linear range of 0-200 µM between citrate concentrations and I545/I454. It has high sensitivity, selective, and rapid detection for citrate. The as-prepared CDs-GMP/Tb as ratiometric fluorescent probes were also used for imaging citrate in living cells. These experiment results showed that CDs-GMP/Tb as ratiometric fluorescent probes could be applied to trace citrate detection in the environmental and biological fields.

A novel method for objectively, rapidly and accurately evaluating burn depth via near infrared spectroscopy.

The accurate and objective evaluation of burn depth is a significant challenge in burn wound care. Herein, we used near infrared spectroscopy (NIRS) technology to measure the different depth of thermal burns in ex vivo porcine models. Based on the intensity of the spectral signals and the diffuse reflection theory, we extracted the optical parameters involved in functional (total hemoglobin and water content) and structural (tissue scattered size and scattered particles) features that reflect the changes in burn depth. Next, we applied support vector regression to construct a model including the optical property parameters and the burn depth. Finally, we histologically verified the burn depth data collected via NIRS. The results showed that our inversion model could achieve an average relative error of about 7.63%, while the NIRS technology diagnostic accuracy was in the range of 50 µm. For the first time, this novel technique provides physicians with real-time burn depth information objectively and accurately.

Full-field burn depth detection based on near-infrared hyperspectral imaging and ensemble regression.

The accurate and instant diagnosis of burn severity is always the key point of optimal wound management and clinical treatment. However, the accuracy of burn depth assessment is low via visual inspection and lacks a quantitative measurement. In this work, a full-field burn depth detection system is proposed using the near-infrared hyperspectral imaging with the ensemble regression. The rotational feature subspace ensemble regression is introduced to establish a complex regression model between the hyperspectral imaging data and the burn depth. By the in vivo measurement of a porcine model, the method can get the average relative error about 7% for the burn depth measurement, which demonstrates that the proposed method can perform an accurate full-field assessment of burn depth and provide more practical references for clinicians.

Multiporous Terbium Phosphonate Coordination Polymer Microspheres as Fluorescent Probes for Trace Anthrax Biomarker Detection.

Lanthanide coordination polymers have been recently regarded as attractive sensing materials because of their selectivity, high sensitivity, and rapid response ability. In this research, the multiporous terbium phosphonate coordination polymer microspheres (TbP-CPs) were prepared as a novel fluorescent probe, which showed a fluorescence turn-on response capability for the detection of the trace anthrax biomarker dipicolinate acid (DPA). The morphology and chemical composition of as-prepared TbP-CPs were characterized in detail. The TbP-CPs have the vegetable-flower-like structure and microporous surface. In addition, the as-prepared TbP-CPs not only possess the merits of convenience and simple preparation with high yield but also have the excellent characters as fluorescent probes, such as high stability, good selectivity, and rapid detection ability within 30 s. This proposed sensor could detect DPA with a linear relationship in concentrations ranging from 0 to 8.0 µM and a high detection sensitivity of 5.0 nM. Furthermore, the successful applications of DPA detection in urine and bovine serum were demonstrated. As a result, the recovery ranged from 93.93-101.6%, and the relative standard deviations (RSD) were less than 5%.

Improving the spatial resolution of volume Bragg grating two-dimensional monochromatic images.

Higher spatial resolution indicates sharper recognition ability in applications. To improve the spatial resolution of volume Bragg grating spectral imagers, quantitative wave vector theory is used to elucidate the formation mechanism of diffraction blur, and the corresponding optimal design approaches are put forward. The simulation results show that the main factors for the spectral image blur are the chromatic blur and diffraction aberration, while the central wavelength deviation further deteriorates these. To deal with these factors, one must optimize the grating period, thickness, slant angle, and refractive index, as well as compress the divergence angle of the incident beam. After optimization under the guidance of the newly defined integrated merit functions, the experimental results show that the optimized smeared point-spread function is reduced by about an order of magnitude. The horizontal spatial resolution of the recorded two-dimensional monochromatic images is improved to 14.3 lines/mm under diffuse reflection illumination.

Active phase locking of thirty fiber channels using multilevel phase dithering method.

An active phase locking of a large-scale fiber array with thirty channels has been demonstrated experimentally. In the experiment, the first group of thirty phase controllers is used to compensate the phase noises between the elements and the second group of thirty phase modulators is used to impose additional phase disturbances to mimic the phase noises in the high power fiber amplifiers. A multi-level phase dithering algorithm using dual-level rectangular-wave phase modulation and time division multiplexing can achieve the same phase control as single/multi-frequency dithering technique, but without coherent demodulation circuit. The phase locking efficiency of 30 fiber channels is achieved about 98.68%, 97.82%, and 96.50% with no additional phase distortion, modulated phase distortion I (±1 rad), and phase distortion II (±2 rad), corresponding to the phase error of λ/54, λ/43, and λ/34 rms. The contrast of the coherent combined beam profile is about 89%. Experimental results reveal that the multi-level phase dithering technique has great potential in scaling to a large number of laser beams.

Recruitment of A20 by the C-terminal domain of NEMO suppresses NF-κB activation and autoinflammatory disease.

Receptor-induced NF-κB activation is controlled by NEMO, the NF-κB essential modulator. Hypomorphic NEMO mutations result in X-linked ectodermal dysplasia with anhidrosis and immunodeficiency, also referred to as NEMO syndrome. Here we describe a distinct group of patients with NEMO C-terminal deletion (ΔCT-NEMO) mutations. Individuals harboring these mutations develop inflammatory skin and intestinal disease in addition to ectodermal dysplasia with anhidrosis and immunodeficiency. Both primary cells from these patients, as well as reconstituted cell lines with this deletion, exhibited increased IκB kinase (IKK) activity and production of proinflammatory cytokines. Unlike previously described loss-of-function mutations, ΔCT-NEMO mutants promoted increased NF-κB activation in response to TNF and Toll-like receptor stimulation. Investigation of the underlying mechanisms revealed impaired interactions with A20, a negative regulator of NF-κB activation, leading to prolonged accumulation of K63-ubiquitinated RIP within the TNFR1 signaling complex. Recruitment of A20 to the C-terminal domain of NEMO represents a novel mechanism limiting NF-κB activation by NEMO, and its absence results in autoinflammatory disease.

Transfection, selection, and colony-picking of human induced pluripotent stem cells TALEN-targeted with a GFP gene into the AAVS1 safe harbor.

Targeted transgene addition can provide persistent gene expression while circumventing the gene silencing and insertional mutagenesis caused by viral vector mediated random integration. This protocol describes a universal and efficient transgene targeted addition platform in human iPSCs based on utilization of validated open-source TALENs and a gene-trap-like donor to deliver transgenes into a safe harbor locus. Importantly, effective gene editing is rate-limited by the delivery efficiency of gene editing vectors. Therefore, this protocol first focuses on preparation of iPSCs for transfection to achieve high nuclear delivery efficiency. When iPSCs are dissociated into single cells using a gentle-cell dissociation reagent and transfected using an optimized program, >50% cells can be induced to take up the large gene editing vectors. Because the AAVS1 locus is located in the intron of an active gene (PPP1R12C), a splicing acceptor (SA)-linked puromycin resistant gene (PAC) was used to select targeted iPSCs while excluding random integration-only and untransfected cells. This strategy greatly increases the chance of obtaining targeted clones, and can be used in other active gene targeting experiments as well. Two weeks after puromycin selection at the dose adjusted for the specific iPSC line, clones are ready to be picked by manual dissection of large, isolated colonies into smaller pieces that are transferred to fresh medium in a smaller well for further expansion and genetic and functional screening. One can follow this protocol to readily obtain multiple GFP reporter iPSC lines that are useful for in vivo and in vitro imaging and cell isolation.

Transcription activator-like effector nuclease (TALEN)-mediated CLYBL targeting enables enhanced transgene expression and one-step generation of dual reporter human induced pluripotent stem cell (iPSC) and neural stem cell (NSC) lines.

Targeted genome engineering to robustly express transgenes is an essential methodology for stem cell-based research and therapy. Although designer nucleases have been used to drastically enhance gene editing efficiency, targeted addition and stable expression of transgenes to date is limited at single gene/locus and mostly PPP1R12C/AAVS1 in human stem cells. Here we constructed transcription activator-like effector nucleases (TALENs) targeting the safe-harbor like gene CLYBL to mediate reporter gene integration at 38%-58% efficiency, and used both AAVS1-TALENs and CLYBL-TALENs to simultaneously knock-in multiple reporter genes at dual safe-harbor loci in human induced pluripotent stem cells (iPSCs) and neural stem cells (NSCs). The CLYBL-TALEN engineered cell lines maintained robust reporter expression during self-renewal and differentiation, and revealed that CLYBL targeting resulted in stronger transgene expression and less perturbation on local gene expression than PPP1R12C/AAVS1. TALEN-mediated CLYBL engineering provides improved transgene expression and options for multiple genetic modification in human stem cells.

Generation of GFP Reporter Human Induced Pluripotent Stem Cells Using AAVS1 Safe Harbor Transcription Activator-Like Effector Nuclease.

Generation of a fluorescent GFP reporter line in human induced pluripotent stem cells (hiPSCs) provides enormous potentials in both basic stem cell research and regenerative medicine. A protocol for efficiently generating such an engineered reporter line by gene targeting is highly desired. Transcription activator-like effector nucleases (TALENs) are a new class of artificial restriction enzymes that have been shown to significantly promote homologous recombination by >1000-fold. The AAVS1 (adeno-associated virus integration site 1) locus is a "safe harbor" and has an open chromatin structure that allows insertion and stable expression of transgene. Here, we describe a step-by-step protocol from determination of TALENs activity, hiPSC culture, and delivery of a donor into AAVS1 targeting site, to validation of targeted integration by PCR and Southern blot analysis using hiPSC line, and a pair of open-source AAVS1 TALENs.

Stable enhanced green fluorescent protein expression after differentiation and transplantation of reporter human induced pluripotent stem cells generated by AAVS1 transcription activator-like effector nucleases.

Human induced pluripotent stem (hiPS) cell lines with tissue-specific or ubiquitous reporter genes are extremely useful for optimizing in vitro differentiation conditions as well as for monitoring transplanted cells in vivo. The adeno-associated virus integration site 1 (AAVS1) locus has been used as a "safe harbor" locus for inserting transgenes because of its open chromatin structure, which permits transgene expression without insertional mutagenesis. However, it is not clear whether targeted transgene expression at the AAVS1 locus is always protected from silencing when driven by various promoters, especially after differentiation and transplantation from hiPS cells. In this paper, we describe a pair of transcription activator-like effector nucleases (TALENs) that enable more efficient genome editing than the commercially available zinc finger nuclease at the AAVS1 site. Using these TALENs for targeted gene addition, we find that the cytomegalovirus-immediate early enhancer/chicken ß-actin/rabbit ß-globin (CAG) promoter is better than cytomegalovirus 7 and elongation factor 1α short promoters in driving strong expression of the transgene. The two independent AAVS1, CAG, and enhanced green fluorescent protein (EGFP) hiPS cell reporter lines that we have developed do not show silencing of EGFP either in undifferentiated hiPS cells or in randomly and lineage-specifically differentiated cells or in teratomas. Transplanting cardiomyocytes from an engineered AAVS1-CAG-EGFP hiPS cell line in a myocardial infarcted mouse model showed persistent expression of the transgene for at least 7 weeks in vivo. Our results show that high-efficiency targeting can be obtained with open-source TALENs and that careful optimization of the reporter and transgene constructs results in stable and persistent expression in vitro and in vivo.

[Three-column plate internal fixation for the treatment of complex tibial plateau fracture through antero-midline and postero-medial approaches].

OBJECTIVE: To study technique and clinical therapeutic effects of internal fixation with three-column plates for the treatment of complex tibial plateau fractures through antero-midline and postero-medial approaches. METHODS: From January 2010 to December 2012, 28 patients with complex tibial plateau fractures were treated with internal fixation using three-column plates through antero-midline and postero-medial approaches. There were 17 males and 11 females, with an average age of 45.3 years old (ranged, 28 to 64 years old). Twelve patients had injuries in the left side and 16 patients had injuries in the right side. According to Schatzker classification, 12 patients were type V, 16 patients were type VI. According to three-column classification, all the patients had injuries of lateral, medial and posterior columns. The mean interval from injury to operation was 9.4 days (ranged, 6 to 15 days). The main clinical symptoms were knee joint swelling, deformity and limitation of motion before operation. The X-ray and CT showed all patients had complex tibial plateau fractures, which involved in the lateral, medial and posterior columns. The therapeutic effects were evaluated by fracture healing time, hospital for special surgery knee score (HSS) at one year after operation. The indexes such as tibial plateau-tibial shaft angle (TPA), posterior slope angle (PA) and femoral-tibial angle (FfA) were compared between immediate postoperation and one year after operation. RESULTS: All incisions primarily healed without postoperative complications such as infection and cutaneous necrosis. All the patients were followed up, and the duration ranged from 12 to 24 months, with a mean of 18.1 months. The bone union time ranged from 5 to 10 months (mean, 7.8 months) after operation. Knee joint swelling and pain disappeared after bony union, and joint function completely recovered. The results of hospital for special surgery knee score (HSS) was 27.81 ± 2.17 in pain, 19.52 ± 2.05 in function,15.82 ± 1.73 in passive range of motion, 8.51 ± 1.32 in muscle strength, 8.33 ± 1.08 in flexion deformity, 9.36 ± 0.52 in joint stability, and the total mean score was 89.35 ± 3.19. According to results of HSS, 20 patients got an excellent result, 5 good,2 fair and 1 poor. There were no significant differences in tibial plateau-tibial shaft angle (TPA), posterior slope angle (PA) and femoral-tibial angle (FTA) between immediate postoperation and one year after operation. CONCLUSION: Three-column plate internal fixation for the treatment of complex tibial plateau fractures through antero-midline and posteromedial approaches is effective to achieve anatomic reduction,rigid internal fixation and early functional exercise.

Direct investigation and accurate control of phase profile in liquid-crystal optical-phased array for beam steering.

An experimental setup and simple method were proposed to investigate and control the actual phase profile in a high-spatial-resolution liquid-crystal optical-phased array (LCOPA). A crossed polarizer and high-resolution microscope objective were employed to transform the light distribution out of the liquid-crystal layer into a polarization-interference pattern in which the phase-profile information was wrapped. The polarization-interference pattern was then directly translated into the actual phase profile. Based on this setup, a method was developed to accurately control the actual phase profile, and the steering efficiency at the steering angle of 16 mrad was increased from 80% to 90%. The proposed method also helps in increasing the steering efficiency when disclination lines appear.

Fiber polarization control based on a fast locating algorithm.

In this article, currently used feedback control algorithms used in the polarization controller, including a simulated annealing algorithm and a gradient algorithm, are analyzed. On this basis, a new method of polarization control feedback algorithm based on a fast locating algorithm is proposed to solve the defects of the original algorithm, such as poor convergence and an extensive time consuming search. It can reduce convergence time and improve the response speed of the polarization controllers. This new endless polarization control algorithm utilizing a four-plate polarization controller is proposed and demonstrated. The results have shown that the response time of the polarization controller is less than 1 ms. The control of polarization is achieved and the output polarization state is stable, while the light intensity fluctuated less than 2%, which can run endless resets freely.

Involvement of PGC-1α in the formation and maintenance of neuronal dendritic spines.

The formation, maintenance and reorganization of synapses are critical for brain development and the responses of neuronal circuits to environmental challenges. Here we describe a novel role for peroxisome proliferator-activated receptor γ co-activator 1α, a master regulator of mitochondrial biogenesis, in the formation and maintenance of dendritic spines in hippocampal neurons. In cultured hippocampal neurons, proliferator-activated receptor γ co-activator 1α overexpression increases dendritic spines and enhances the molecular differentiation of synapses, whereas knockdown of proliferator-activated receptor γ co-activator 1α inhibits spinogenesis and synaptogenesis. Proliferator-activated receptor γ co-activator 1α knockdown also reduces the density of dendritic spines in hippocampal dentate granule neurons in vivo. We further show that brain-derived neurotrophic factor stimulates proliferator-activated receptor γ co-activator-1α-dependent mitochondrial biogenesis by activating extracellular signal-regulated kinases and cyclic AMP response element-binding protein. Proliferator-activated receptor γ co-activator-1α knockdown inhibits brain-derived neurotrophic factor-induced dendritic spine formation without affecting expression and activation of the brain-derived neurotrophic factor receptor tyrosine receptor kinase B. Our findings suggest that proliferator-activated receptor γ co-activator-1α and mitochondrial biogenesis have important roles in the formation and maintenance of hippocampal dendritic spines and synapses.

Tunable liquid crystal microlens array using hole patterned electrode structure with ultrathin glass slab.

A configuration of hole patterned electrode liquid crystal microlens array with an ultrathin glass slab was fabricated. To reduce the fringing electric field effect and avoid the occurrence of disclination lines, an ultrathin glass slab was introduced between the patterned electrode and liquid crystal layer. The glass slab thickness played an important role in effecting the optical performance of the liquid crystal microlens array. An optimum thickness of 30 µm was selected employing numerical simulation method. Using this method, we demonstrated a microlens array that greatly improved the phase profile and focus power. The dynamic focal range of the liquid crystal microlens array may extend from <1.2 mm to >8 mm and the minimum diameter of the focus spot could be as small as 15 µm.

Antiparallel ß-sheet architecture in Iowa-mutant ß-amyloid fibrils.

Wild-type, full-length (40- and 42-residue) amyloid ß-peptide (Aß) fibrils have been shown by a variety of magnetic resonance techniques to contain cross-ß structures in which the ß-sheets have an in-register parallel supramolecular organization. In contrast, recent studies of fibrils formed in vitro by the Asp23-to-Asn mutant of 40-residue Aß (D23N-Aß(1-40)), which is associated with early onset neurodegeneration, indicate that D23N-Aß(1-40) fibrils can contain either parallel or antiparallel ß-sheets. We report a protocol for producing structurally pure antiparallel D23N-Aß(1-40) fibril samples and a series of solid state nuclear magnetic resonance and electron microscopy measurements that lead to a specific model for the antiparallel D23N-Aß(1-40) fibril structure. This model reveals how both parallel and antiparallel cross-ß structures can be constructed from similar peptide monomer conformations and stabilized by similar sets of interactions, primarily hydrophobic in nature. We find that antiparallel D23N-Aß(1-40) fibrils are thermodynamically metastable with respect to conversion to parallel structures, propagate less efficiently than parallel fibrils in seeded fibril growth, and therefore must nucleate more efficiently than parallel fibrils in order to be observable. Experiments in neuronal cell cultures indicate that both antiparallel and parallel D23N-Aß(1-40) fibrils are cytotoxic. Thus, our antiparallel D23N-Aß(1-40) fibril model represents a specific "toxic intermediate" in the aggregation process of a disease-associated Aß mutant.

[Research on LC-based spectral imaging system for visible band].

LC-based tunable filter with large aperture has been developed utilizing the effect of electric controlled birefringence. Spectral test indicated that this filter can operate in the visible band with an average 20 nm FWHM. A small scale spectral imaging system was established based on this tunable filter. Spectral imaging experiments on a certain number of samples show that this system can be tuned continuously with random-access selection of any wavelength, and has a higher level of resolving power in respect of both imaging and spectral tuning in the visible band, which has a brilliant application potentiality in biology, iatrology, environmental protection, resource detection through hyper-spectral imaging or ultra-spectral imaging.