Transgenic human HOXB1-9 directs anterior-posterior axial skeleton pattern in Hoxb1-9 deficient mice.

The cervical and anterior thoracic regions of mammals generally exhibit similar vertebral numbers and identities along the anterior-posterior axis. The position of the forelimbs along the axial skeleton is also generally conserved. In contrast, the number of lumbar and sacral vertebrae and pelvic position exhibit more variation, correlating with posture and locomotion. The molecular mechanisms that lead to these conserved and variable axial skeletal patterns between species are not fully understood. Here we use a human HOXB1-9 transgene to complement a HoxB1-9 deficiency in the mouse. In TgHOXB1-9 mice, human HOXB1, B2, B3, and B4 (HOXB1-4) genes were expressed in mouse embryos in patterns similar to mouse Hoxb1-4 genes. Human transgene expression rescued the cervical and anterior thoracic vertebral patterning defects of HoxB1-9Δ/Δ mice. In addition, the posterior shift in forelimb position of HoxB1-9Δ/Δ mice was rescued by the transgene. Interestingly, the position of the lumbar-sacral transition in both TgHOXB1-9; HoxB1-9Δ/Δ and TgHOXB1-9; HoxB1-9+/+ mice was altered from six lumbar and four sacral vertebrae found in wild-type controls to five lumbar and five sacral vertebrae. The change in the position of the lumbar-sacral transition consequently altered the position of the pelvis. In contrast to the conserved expression of human HOXB1-4 genes in TgHOXB1-9 mouse embryos, the anterior border of human HOXB9 expression in the neural tube and paraxial mesoderm was shifted posteriorly by 2-3 somites compared to the anterior boundary of endogenous Hoxb9 expression. These findings suggest that conservation and variation in Hoxb/HOXB expression contributes to conserved and species-specific vertebral pattern and limb position.

A universal strategy for the fabrication of single-photon and multiphoton NIR nanoparticles by loading organic dyes into water-soluble polymer nanosponges.

The development of optical organic nanoparticles (NPs) is desirable and widely studied. However, most organic dyes are water-insoluble such that the derivatization and modification of these dyes are difficult. Herein, we demonstrated a simple platform for the fabrication of organic NPs designed with emissive properties by loading ten different organic dyes (molar masses of 479.1-1081.7 g/mol) into water-soluble polymer nanosponges composed of poly(styrene-alt-maleic acid) (PSMA). The result showed a substantial improvement over the loading of commercial dyes (3.7-50% loading) while preventing their spontaneous aggregation in aqueous solutions. This packaging strategy includes our newly synthesized organic dyes (> 85% loading) designed for OPVs (242), DSSCs (YI-1, YI-3, YI-8), and OLEDs (ADF-1-3, and DTDPTID) applications. These low-cytotoxicity organic NPs exhibited tunable fluorescence from visible to near-infrared (NIR) emission for cellular imaging and biological tracking in vivo. Moreover, PSMA NPs loaded with designed NIR-dyes were fabricated, and photodynamic therapy with these dye-loaded PSMA NPs for the photolysis of cancer cells was achieved when coupled with 808 nm laser excitation. Indeed, our work demonstrates a facile approach for increasing the biocompatibility and stability of organic dyes by loading them into water-soluble polymer-based carriers, providing a new perspective of organic optoelectronic materials in biomedical theranostic applications.

Enhancing the signal contrast ratio and stability of liquid crystal-based sensors by using fine grids made by photolithography of photoresists.

We prepared fine grid patterns on a glass substrate through photolithography of photoresists; we filled photoresist grids with liquid crystals (LCs) to construct LC-based sensors. Scanning electron microscopy images revealed that the photoresist grids were flat, smooth, and 3.0-8.0 µm thick. In contrast to conventional LC-based sensors, in which LCs are filled in metal grids placed on glass substrates, our results proved that LC-based sensors constructed using photoresist grids exhibited a larger signal contrast ratio, better signal stability in aqueous solutions and lower limit of detection for mercuric ions. All these characteristics enhanced the performance of the LC-based sensors.

A rapid and highly sensitive paper-based colorimetric device for the on-site screening of ammonia gas.

A rapid and highly sensitive paper-based colorimetric device for the on-site detection of ammonia (NH3) gas is presented in this study. The detection principle of this device is based upon a change of color from red to yellow on a paper that has been immobilized with a pH indicator, i.e., methyl orange (pKa = 3.4), in the presence of NH3 gas. The color signal of the device can be measured through the hue channel of an HSL system via the application of a smartphone. This device can detect the amount of NH3 gas within 3 min. The linear relationship between the NH3 gas concentration and the hue signal was found to be in the range from 6.0 to 54.0 ppbv with R2 = 0.9971, and the limit of detection was found to be 2.0 ppbv. In addition, this device showed remarkably high selectivity to NH3 gas amongst the other common volatile organic compounds and general gases that are present in environmental air without the assistance of any membrane material. Furthermore, we demonstrated the applicability of this device for the detection of total NH3 gas at a chicken farm and in a laboratory, with relative standard deviations of 6.2% and 5.4%, respectively. The developed NH3 gas device in the study is easy to operate and cost-effective, with the reduction of a large consumption of chemical reagents; also, its signals can be measured simply and then recorded through a smartphone. It is suitable for the application of routine on-site detection of NH3 gas, especially concerning regions which have limited resources.

Quantitative analysis of liquid crystal-based immunoassay using rectangular capillaries as sensing platform.

In past studies, liquid crystal (LC)-based immunoassays were accomplished by fabricating an LC cell with two pieces of glass slides after immunobinding, which makes the determination of the immunoassay not in real-time and requires trained personnel. Herein, we developed the LC-based immunoassay by using rectangular capillaries as the substrate for immunobinding. The inner surface of rectangular capillaries was decorated with a long alkyl saline, dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride (DMOAP), followed by immobilization of human serum albumin (HSA) as the probe. In this situation, the orientation of LC was homeotropic and dark LC image was observed under polarized light. When the solution containing anti-human serum albumin (anti-HSA) were dispensed into the capillary through capillary action, the specific immunobinding between HSA and anti-HSA formed an immunocomplex on the inner surface of capillary, which disrupted the original orientation of LC and led to a dark-to-bright transition of the LC images. The quantification of anti-HSA can be achieved by measuring the length of the bright LC image in the rectangular capillary. By using this immunoassay, the limit of detection (LOD) for anti-HSA is 1 µg/mL, and it did not respond to HSA and anti-human immunoglobulin G (anti-h-IgG). On the other hand, the diversity of the LC-based immunoassay can be extended for HSA detection when we immobilized anti-HSA in the capillary. Because the post-fabrication of LC cell was waived by using rectangular capillaries to develop the LC-based immunoassay, it is more convenient for users to handle and collect more reliable data. Moreover, the results of the immunoassay were visualized through naked-eye and could be recorded by a smartphone; it is more suitable for portable and point-of-care applications.

Loss of smooth muscle cell hypoxia inducible factor-1α underlies increased vascular contractility in pulmonary hypertension.

Pulmonary arterial hypertension (PAH) is an often fatal disease with limited treatment options. Whereas current data support the notion that, in pulmonary artery endothelial cells (PAECs), expression of transcription factor hypoxia inducible factor-1α (HIF-1α) is increased, the role of HIF-1α in pulmonary artery smooth muscle cells (PASMCs) remains controversial. This study investigates the hypothesis that, in PASMCs from patients with PAH, decreases in HIF-1α expression and activity underlie augmented pulmonary vascular contractility. PASMCs and tissues were isolated from nonhypertensive control patients and patients with PAH. Compared with controls, HIF-1α and Kv1.5 protein expression were decreased in PAH smooth muscle cells (primary culture). Myosin light chain (MLC) phosphorylation and MLC kinase (MLCK) activity-major determinants of vascular tone-were increased in patients with PAH. Cofactors involved in prolyl hydroxylase domain activity were increased in PAH smooth muscle cells. Functionally, PASMC contractility was inversely correlated with HIF-1α activity. In PASMCs derived from patients with PAH, HIF-1α expression is decreased, and MLCK activity, MLC phosphorylation, and cell contraction are increased. We conclude that compromised PASMC HIF-1α expression may contribute to the increased tone that characterizes pulmonary hypertension.-Barnes, E. A., Chen, C.-H., Sedan, O., Cornfield, D. N. Loss of smooth muscle cell hypoxia inducible factor-1α underlies increased vascular contractility in pulmonary hypertension.

Fixation behavior in macular dystrophy assessed by microperimetry.

PURPOSE: To investigate the fixation behavior in macular dystrophy using microperimetry. METHODS: This retrospective study included patients with macular dystrophy and unilateral macular pucker. Macular dystrophic eyes were compared based on fixation within or outside of the atrophic region. The normal fellow eyes in patients with unilateral macular pucker formed the control group. Clinical and demographic characteristics of age, sex, best-corrected visual acuity, spherical equivalent, and fixation behavior (which included foveal mean sensitivity (MS), fixation MS, MS improvement, stability, centrality, and eccentric distance of fixation) were analyzed. A total of 58 patients were recruited, comprising 29 eyes of 29 patients in the macular dystrophy group and 29 eyes of 29 patients in the control group. RESULTS: Compared to the control group, patients with macular dystrophy had significantly poorer visual acuity, foveal MS, fixation MS, stability, and centrality, and more eccentric preferred retinal locations (PRLs). In macular dystrophy, the PRLs were most common on the superior side (48.3%). Compared to fixation in the atrophic region, PRLs out of the atrophic lesion gained more MS (7.41 vs. 0.89 dB, p = 0.001), although with less stable fixation (10.0 vs. 47.4%, p = 0.044). By multivariate linear regression, eccentric distance was found to be significantly associated with MS improvement (p = 0.023). CONCLUSIONS: The commonest location of PRLs in macular dystrophy is anatomically superior to the lesion. The dystrophic eye can gain better sensitivity by using PRLs outside the atrophic area.

Factors associated with corneal epithelial defects after pars plana vitrectomy.

PURPOSE: To investigate the risk factors associated with corneal epithelial defects (CED) and delayed healing (exceeding 1 week) following pars plana vitrectomy (PPV). METHODS: This retrospective study enrolled patients who underwent PPV at a single center in Taiwan between 2011 and 2012. Medical records were reviewed, including demographic, underlying disease, surgical indication, operation parameters, and existence of CED. These data were statistically analyzed. All patients were evaluated during follow-ups at day 1 and week 1 after PPV. Patients with persistent CED 1 week after PPV were diagnosed with delayed healing. RESULTS: A total of 255 patients were included in the study, consisting of 139 men and 116 women, with a mean age of 56.9 years. PPV was performed under the indications of rhegmatogenous retinal detachment (RRD), diabetic retinopathy, or vitreoretinal interface disease. Out of 255 eyes, 59 developed CED 1 day after surgery (23.1%), and CED was associated with younger age, diabetes mellitus (DM), RRD, longer duration of surgery, and silicon oil use during surgery. Among them, seven patients (11.9%) demonstrated delayed healing, which was associated with a higher rate of DM (p = 0.085), compared to patients who healed within 1 week. CONCLUSION: Patients with RRD, longer duration of surgery, and DM may be at risk of developing CED after PPV. In addition, patients with DM demonstrated a higher incidence of delayed corneal healing.

Systematic mapping of occluded genes by cell fusion reveals prevalence and stability of cis-mediated silencing in somatic cells.

Both diffusible factors acting in trans and chromatin components acting in cis are implicated in gene regulation, but the extent to which either process causally determines a cell's transcriptional identity is unclear. We recently used cell fusion to define a class of silent genes termed "cis-silenced" (or "occluded") genes, which remain silent even in the presence of trans-acting transcriptional activators. We further showed that occlusion of lineage-inappropriate genes plays a critical role in maintaining the transcriptional identities of somatic cells. Here, we present, for the first time, a comprehensive map of occluded genes in somatic cells. Specifically, we mapped occluded genes in mouse fibroblasts via fusion to a dozen different rat cell types followed by whole-transcriptome profiling. We found that occluded genes are highly prevalent and stable in somatic cells, representing a sizeable fraction of silent genes. Occluded genes are also highly enriched for important developmental regulators of alternative lineages, consistent with the role of occlusion in safeguarding cell identities. Alongside this map, we also present whole-genome maps of DNA methylation and eight other chromatin marks. These maps uncover a complex relationship between chromatin state and occlusion. Furthermore, we found that DNA methylation functions as the memory of occlusion in a subset of occluded genes, while histone deacetylation contributes to the implementation but not memory of occlusion. Our data suggest that the identities of individual cell types are defined largely by the occlusion status of their genomes. The comprehensive reference maps reported here provide the foundation for future studies aimed at understanding the role of occlusion in development and disease.

GORE-TEX VASCULAR GRAFT FOR MACULAR BUCKLING IN HIGH MYOPIA EYES.

PURPOSE: To evaluate a new application of an expanded polytetrafluoroethylene (Gore-Tex) vascular graft for use in macular buckling surgery for treatment of highly myopic eyes. METHODS: The Gore-Tex vascular graft was used as a macular buckling material in eight consecutive cases of myopic macular diseases which included fovea detachment, foveoschisis, or macular hole retinal detachment. RESULTS: Retinal reattachment was achieved in all cases except one which had partial resolution (88%). The postoperative best-corrected visual acuity ranged from 20/2000 to 20/100 depending on the degree preexisting macular degeneration, and significant better than the preoperative best-corrected visual acuity (P = 0.048, paired t-test). During the follow-up period, which ranged from 8 months to 3 years, no eye developed buckle-related complications such as infection or dislocation. CONCLUSION: The initial pilot results from this series using a Gore-Tex graft for macular buckling is promising. Throughout the follow-up period, the Gore-Tex was well tolerated in the highly myopic eyes. Large scale and long-term follow-up is warranted.

Pulmonary artery smooth muscle cell endothelin-1 expression modulates the pulmonary vascular response to chronic hypoxia.

Endothelin-1 (ET-1) increases pulmonary vascular tone through direct effects on pulmonary artery smooth muscle cells (PASMC) via membrane-bound ET-1 receptors. Circulating ET-1 contributes to vascular remodeling by promoting SMC proliferation and migration and inhibiting SMC apoptosis. Although endothelial cells (EC) are the primary source of ET-1, whether ET-1 produced by SMC modulates pulmonary vascular tone is unknown. Using transgenic mice created by crossbreeding SM22α-Cre mice with ET-1(flox/flox) mice to selectively delete ET-1 in SMC, we tested the hypothesis that PASMC ET-1 gene expression modulates the pulmonary vascular response to hypoxia. ET-1 gene deletion and selective activity of SM22α promoter-driven Cre recombinase were confirmed. Functional assays were performed under normoxic (21% O2) or hypoxic (5% O2) conditions using murine PASMC obtained from ET-1(+/+) and ET-1(-/-) mic and in human PASMC (hPASMC) after silencing of ET-1 using siRNA. Under baseline conditions, there was no difference in right ventricular systolic pressure (RVSP) between SM22α-ET-1(-/-) and SM22α-ET-1(+/+) (control) littermates. After exposure to hypoxia (10% O2, 21-24 days), RVSP was and vascular remodeling were less in SM22α-ET-1(-/-) mice compared with control littermates (P < 0.01). Loss of ET-1 decreased PASMC proliferation and migration and increased apoptosis under normoxic and hypoxic conditions. Exposure to selective ET-1 receptor antagonists had no effect on either the hypoxia-induced hPASMC proliferative or migratory response. SMC-specific ET-1 deletion attenuates hypoxia-induced increases in pulmonary vascular tone and structural remodeling. The observation that loss of ET-1 inhibited SMC proliferation, survival, and migration represents evidence that ET-1 derived from SMC plays a previously undescribed role in modulating the response of the pulmonary circulation to hypoxia. Thus PASMC ET-1 may modulate vascular tone independently of ET-1 produced by EC.

Activation of the nuclear factor-κB pathway during postnatal lung inflammation preserves alveolarization by suppressing macrophage inflammatory protein-2.

A significant portion of lung development is completed postnatally during alveolarization, rendering the immature lung vulnerable to inflammatory stimuli that can disrupt lung structure and function. Although the NF-κB pathway has well-recognized pro-inflammatory functions, novel anti-inflammatory and developmental roles for NF-κB have recently been described. Thus, to determine how NF-κB modulates alveolarization during inflammation, we exposed postnatal day 6 mice to vehicle (PBS), systemic lipopolysaccharide (LPS), or the combination of LPS and the global NF-κB pathway inhibitor BAY 11-7082 (LPS + BAY). LPS impaired alveolarization, decreased lung cell proliferation, and reduced epithelial growth factor expression. BAY exaggerated these detrimental effects of LPS, further suppressing proliferation and disrupting pulmonary angiogenesis, an essential component of alveolarization. The more severe pathology induced by LPS + BAY was associated with marked increases in lung and plasma levels of macrophage inflammatory protein-2 (MIP-2). Experiments using primary neonatal pulmonary endothelial cells (PEC) demonstrated that MIP-2 directly impaired neonatal PEC migration in vitro; and neutralization of MIP-2 in vivo preserved lung cell proliferation and pulmonary angiogenesis and prevented the more severe alveolar disruption induced by the combined treatment of LPS + BAY. Taken together, these studies demonstrate a key anti-inflammatory function of the NF-κB pathway in the early alveolar lung that functions to mitigate the detrimental effects of inflammation on pulmonary angiogenesis and alveolarization. Furthermore, these data suggest that neutralization of MIP-2 may represent a novel therapeutic target that could be beneficial in preserving lung growth in premature infants exposed to inflammatory stress.

Ligand-doped liquid crystal sensor system for detecting mercuric ion in aqueous solutions.

We developed a liquid crystal (LC) sensor system for detecting mercuric ion (Hg(2+)) in aqueous solutions. In this system, 4-cyano-4'-pentyl biphenyl (5CB) was doped with a sulfur- and nitrogen-containing ligand 5-(pyridine-4-yl)-2-(5-(pyridin-4-yl)thiophen-2-yl)thiazole (ZT) as the Hg(2+) specific LCs. When the system was immersed in the solution containing Hg(2+), the complex of ZT and Hg(2+) formed, which disrupted the orientation of LC and lead to a dark-to-bright transition of the image of LCs. From mercuric binding titrations monitored by UV-vis spectroscopy, it was found that 1:1 Hg(2+)/ZT complexes were formed. The limit of detection (LOD) of the system to Hg(2+) is 10 µM, and it did not respond to Cd(2+), Zn(2+), Cu(2+), Pb(2+), Fe(+), Mg(2+), Ca(2+), Na(+), and K(+). Besides, we also demonstrated that this system is capable of detecting Hg(2+) in tap water and pond water. Because the signal of this system is colorful under ambient light, which is readily understood by normal users, it can be used as a portable device to monitor the water quality at any location.

Enhancing Specific Detectivity and Device Stability in Vacuum-Deposited Organic Photodetectors Utilizing Nonfullerene Acceptors.

Organic photodetector (OPD) studies have undergone a revolutionary transformation by introducing nonfullerene acceptors (NFAs), which provide substantial benefits such as tunable band gaps and enhanced absorption in the visible spectrum. Vacuum-processed small-molecule-based OPD devices are presented in this study by utilizing a blend of boron subphthalocyanine (SubPc) and chlorinated subphthalocyanine (Cl6SubPc) as the active layer. Four different active layer thicknesses are further investigated to understand the intrinsic phenomena, unveiling the suppression of dark current density while maintaining photoexcitation and charge separation efficiency. Experimental results reveal that, at an applied bias of -3 V, the 50-nm-thick active layer achieves a remarkably low dark current density of 1.002 nA cm-2 alongside a high external quantum efficiency (EQE) of 52.932% and a responsivity of 0.226 A W-1. These impressive performance metrics lead to a specific detectivity of 1.263 × 1013 Jones. Furthermore, the findings offer new insights into intrinsic phenomena within the bulk heterojunction (BHJ), such as thermally generated current and exciton quenching. This integration is potentially well-heeled to revolutionize display technology by combining high-sensitivity photodetection, offering new possibilities for novel display panels with sensing applications.

Graphene/liquid crystal based terahertz phase shifters.

Due to its high electrical conductivity and excellent transmittance at terahertz frequencies, graphene is a promising candidate as transparent electrodes for terahertz devices. We demonstrate a liquid crystal based terahertz phase shifter with the graphene films as transparent electrodes. The maximum phase shift is 10.8 degree and the saturation voltage is 5 V with a 50 µm liquid crystal cell. The transmittance at terahertz frequencies and electrical conductivity depending on the number of graphene layer are also investigated. The proposed phase shifter provides a continuous tunability, fully electrical controllability, and low DC voltage operation.

Positional Isomeric Cyano-Substituted Bis(2-phenylpyridine)(acetylacetonate)iridium Complexes for Efficient Organic Light-Emitting Diodes with Extended Color Range.

Bis(2-phenylpyridine)(acetylacetonate)iridium, Ir(ppy)2(acac), is a benchmark green emitter for phosphorescent organic light-emitting diodes (PhOLEDs). In this work, we reported three positional isomeric cyano-substituted Ir(ppy)2(acac) complexes, i.e., Ir(3-CN), Ir(4-CN), and Ir(10-CN), with the emission in the yellow to red region (544-625 nm). Through theoretical investigation and single-crystal analysis, it was found that the introduction of cyano substitution at various positions of the ppy ligand allows for tuning the electron distribution and coordination bond length of Ir complexes. Therefore, the charge transfer property of Ir complexes is enhanced such that the energy gap of the cyano-substituted Ir(ppy)2(acac) complexes was reduced. In addition, Ir(3-CN), Ir(4-CN), and Ir(10-CN) exhibited high PLQYs of 83, 54, and 75%, respectively, with the phosphorescence lifetime in the range of 0.79-2.08 µs. Notably, the device utilizing Ir(3-CN) as the emitter exhibited a maximum external quantum efficiency (EQE) of 25.4%, current efficiency of 56.9 cd A-1, power efficiency of 68.7 lm W-1, and brightness of 61,340 cd m-2 at 8 V. The EQE of this device remained 24.3 and 19.9% at luminances of 1,000 and 10,000 cd m-2, corresponding to the efficiency roll-off of 4.3 and 21.7%, respectively. Comparing to the Ir complexes using the ligand with an extended conjugated structure, our results demonstrated a simple molecular design strategy for phosphorescence emitters with reduced molecular weight for efficient PhOLEDs in the yellow to red color region.

Spiral NeuroString: High-Density Soft Bioelectronic Fibers for Multimodal Sensing and Stimulation.

Bioelectronic fibers hold promise for both research and clinical applications due to their compactness, ease of implantation, and ability to incorporate various functionalities such as sensing and stimulation. However, existing devices suffer from bulkiness, rigidity, limited functionality, and low density of active components. These limitations stem from the difficulty to incorporate many components on one-dimensional (1D) fiber devices due to the incompatibility of conventional microfabrication methods (e.g., photolithography) with curved, thin and long fiber structures. Herein, we introduce a fabrication approach, ‶spiral transformation″, to convert two-dimensional (2D) films containing microfabricated devices into 1D soft fibers. This approach allows for the creation of high density multimodal soft bioelectronic fibers, termed Spiral NeuroString (S-NeuroString), while enabling precise control over the longitudinal, angular, and radial positioning and distribution of the functional components. We show the utility of S-NeuroString for motility mapping, serotonin sensing, and tissue stimulation within the dynamic and soft gastrointestinal (GI) system, as well as for single-unit recordings in the brain. The described bioelectronic fibers hold great promises for next-generation multifunctional implantable electronics.

Inhibiting NF-κB in the developing lung disrupts angiogenesis and alveolarization.

Bronchopulmonary dysplasia (BPD), a chronic lung disease of infancy, is characterized by arrested alveolar development. Pulmonary angiogenesis, mediated by the vascular endothelial growth factor (VEGF) pathway, is essential for alveolarization. However, the transcriptional regulators mediating pulmonary angiogenesis remain unknown. We previously demonstrated that NF-κB, a transcription factor traditionally associated with inflammation, plays a unique protective role in the neonatal lung. Therefore, we hypothesized that constitutive NF-κB activity is essential for postnatal lung development. Blocking NF-κB activity in 6-day-old neonatal mice induced the alveolar simplification similar to that observed in BPD and significantly reduced pulmonary capillary density. Studies to determine the mechanism responsible for this effect identified greater constitutive NF-κB in neonatal lung and in primary pulmonary endothelial cells (PEC) compared with adult. Moreover, inhibiting constitutive NF-κB activity in the neonatal PEC with either pharmacological inhibitors or RNA interference blocked PEC survival, decreased proliferation, and impaired in vitro angiogenesis. Finally, by chromatin immunoprecipitation, NF-κB was found to be a direct regulator of the angiogenic mediator, VEGF-receptor-2, in the neonatal pulmonary vasculature. Taken together, our data identify an entirely novel role for NF-κB in promoting physiological angiogenesis and alveolarization in the developing lung. Our data suggest that disruption of NF-κB signaling may contribute to the pathogenesis of BPD and that enhancement of NF-κB may represent a viable therapeutic strategy to promote lung growth and regeneration in pulmonary diseases marked by impaired angiogenesis.

Inhibition of transforming growth factor ß worsens elastin degradation in a murine model of Kawasaki disease.

Kawasaki disease (KD) is an acute inflammatory illness marked by coronary arteritis. However, the factors increasing susceptibility to coronary artery lesions are unknown. Because transforming growth factor (TGF) ß increases elastin synthesis and suppresses proteolysis, we hypothesized that, in contrast to the benefit observed in aneurysms forming in those with Marfan syndrome, inhibition of TGF-ß would worsen inflammatory-induced coronary artery lesions. By using a murine model of KD in which injection of Lactobacillus casei wall extract (LCWE) induces coronary arteritis, we show that LCWE increased TGF-ß signaling in the coronary smooth muscle cells beginning at 2 days and continuing through 14 days, the point of peak coronary inflammation. By 42 days, LCWE caused fragmentation of the internal and external elastic lamina. Blocking TGF-ß by administration of a neutralizing antibody accentuated the LCWE-mediated fragmentation of elastin and induced an overall loss of medial elastin without increasing the inflammatory response. We attributed these increased pathological characteristics to a reduction in the proteolytic inhibitor, plasminogen activator inhibitor-1, and an associated threefold increase in matrix metalloproteinase 9 activity compared with LCWE alone. Therefore, our data demonstrate that in the coronary arteritis associated with KD, TGF-ß suppresses elastin degradation by inhibiting plasmin-mediated matrix metalloproteinase 9 activation. Thus, strategies to block TGF-ß, used in those with Marfan syndrome, are unlikely to be beneficial and could be detrimental.

High-mobility group box 1 protein is implicated in advanced glycation end products-induced vascular endothelial growth factor A production in the rat retinal ganglion cell line RGC-5.

PURPOSE: High-mobility group box 1 protein (HMGB1) has been reported to be a potent proangiogenic factor induced by inflammatory stress. In this study, we explore the role of HMGB1 in advanced glycation end products (AGEs)-induced vascular endothelial growth factor A (VEGF-A) production in rat retinal ganglion cell line 5 (RGC-5) cells. METHODS: The VEGF-A protein and mRNA levels in conditioned medium of RGC-5 cells incubated with AGE-modified BSA (AGE-BSA) were examined with real-time PCR and enzyme-linked immunosorbent assay (ELISA), and BSA-treated cells were used as controls. The expression of HMGB1, c-Jun N-terminal kinase (JNK), extracellular-signal-regulated kinase (ERK), and p38 mitogen-activated protein kinase (p38 MAPK) was assessed with immunofluorescence and western blot analysis. Reactive oxidative species (ROS) were detected with flow cytometry measurements of peroxide-dependent oxidation of 2'-7'-dichlorofluorescein-diacetate (DCFH-DA). N-Acetyl-L-cysteine (NAC), glycyrrhizin (GZ), and SP600125 were used to block ROS, HMGB1, and JNK, respectively. RESULTS: Compared with the BSA controls, the RGC-5 cells incubated with AGE-BSA showed a dose- and time-dependent increase in VEGF-A mRNA and VEGF-A protein secretion in the supernatant, with the highest levels achieved at 24 h. AGE-BSA stimulated a significant release of HMGB1 in the supernatant and a significant increase of intracellular ROS production at 3 h. NAC blocked HMGB1 production in a dose-dependent manner. Blocking with GZ, NAC, and JNK significantly suppressed AGE-induced VEGF-A production. CONCLUSIONS: HMGB1 is implicated in the production of VEGF-A in retinal ganglion cell line-5 (RGC-5). Blocking HMGB1, ROS, or the JNK pathway may attenuate VEGF-A production, suggesting HMGB1 and related signaling molecules play a role in diabetic retinopathy.