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It is self-evident that our chests expand and contract during breathing but, surprisingly, exactly how individual alveoli change shape over the respiratory cycle is still a matter of debate. Some argue that all the alveoli expand and contract rhythmically. Others claim that the lung volume change is due to groups of alveoli collapsing and reopening during ventilation. Although this question might seem to be an insignificant detail for healthy individuals, it might be a matter of life and death for patients with compromised lungs. Past analyses were based on static post-mortem preparations primarily due to technological limitations, and therefore, by definition, incapable of providing dynamic information. In contrast, this study provides the first comprehensive dynamic data on how the shape of the alveoli changes, and, further, provides valuable insights into the optimal lung volume for efficient gas exchange. It is concluded that alveolar micro-dynamics is nonlinear; and at medium lung volume, alveoli expand more than the ducts., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

We report the development of a nanotechnology to co-deliver chemocoxib A with a reactive oxygen species (ROS)-activatable and COX-2 targeted pro-fluorescent probe, fluorocoxib Q (FQ) enabling real time visualization of COX-2 and CA drug delivery into solid cancers, using a di-block PPS 135 - b -POEGA 17 copolymer, selected for its intrinsic responsiveness to elevated reactive oxygen species (ROS), a key trait of the tumor microenvironment. FQ and CA were synthesized independently, then co-encapsulated within micellar PPS 135 - b -POEGA 17 co-polymeric nanoparticles (FQ-CA-NPs), and were assessed for cargo concentration, hydrodynamic diameter, zeta potential, and ROS-dependent cargo release. The uptake of FQ-CA-NPs in mouse mammary cancer cells and cargo release was assessed by fluorescence microscopy. Intravenous delivery of FQ-CA-NPs to mice harboring orthotopic mammary tumors, followed by vital optimal imaging, was used to assess delivery to tumors in vivo . The CA-FQ-NPs exhibited a hydrodynamic diameter of 109.2 ± 4.1 nm and a zeta potential (σ) of -1.59 ± 0.3 mV. Fluorescence microscopy showed ROS-dependent cargo release by FQ-CA-NPs in 4T1 cells, decreasing growth of 4T1 breast cancer cells, but not affecting growth of primary human mammary epithelial cells (HMECs). NP-derived fluorescence was detected in mammary tumors, but not in healthy organs. Tumor LC-MS/MS analysis identified both CA (2.38 nmol/g tumor tissue) and FQ (0.115 nmol/g tumor tissue), confirming the FQ-mediated image guidance of CA delivery in solid tumors. Thus, co-encapsulation of FQ and CA into micellar nanoparticles (FQ-CA-NPs) enabled ROS-sensitive drug release and COX-2-targeted visualization of solid tumors.

Biopolymers are essential building blocks that constitute cells and tissues with well-defined molecular structures and diverse biological functions. Their three-dimensional (3D) complex architectures are used to analyze, control, and mimic various cells and their ensembles. However, the free-form and high-resolution structuring of various biopolymers remain challenging because their structural and rheological control depend critically on their polymeric types at the submicron scale. Here, direct 3D writing of intact biopolymers is demonstrated using a systemic combination of nanoscale confinement, evaporation, and solidification of a biopolymer-containing solution. A femtoliter solution is confined in an ultra-shallow liquid interface between a fine-tuned nanopipette and a chosen substrate surface to achieve directional growth of biopolymer nanowires via solvent-exclusive evaporation and concurrent solution supply. The evaporation-dependent printing is biopolymer type-independent, therefore, the 3D motor-operated precise nanopipette positioning allows in situ printing of nucleic acids, polysaccharides, and proteins with submicron resolution. By controlling concentrations and molecular weights, several different biopolymers are reproducibly patterned with desired size and geometry, and their 3D architectures are biologically active in various solvents with no structural deformation. Notably, protein-based nanowire patterns exhibit pin-point localization of spatiotemporal biofunctions, including target recognition and catalytic peroxidation, indicating their application potential in organ-on-chips and micro-tissue engineering., (© 2023 The Authors. Advanced Science published by Wiley-VCH GmbH.)

Understanding how the alveolar mechanics work in live lungs is essential for comprehending how the lung behaves during breathing. Due to the lack of appropriate imaging tools, previous research has suggested that alveolar morphologies are polyhedral rather than spherical based on a 2D examination of alveoli in fixed lungs. Here, we directly observe high-resolution 3D alveoli in live mice lungs utilizing synchrotron x-ray microtomography to show spherical alveolar morphologies from the live lungs. Our measurements from x-ray microtomography show high sphericity, low packing density, big alveolar size, and low osmotic pressure, indicating that spherical alveolar morphologies are natural in living lungs. The alveolar packing fraction is quite low in live lungs, where the spherical alveoli would behave like free bubbles, while the confinement of alveolar clusters in fixed lungs would lead to significant morphological deformations of the alveoli appearing polyhedral. Direct observations of the spherical alveolar shapes will help understand and treat lung disease and ventilation., (© 2023. The Author(s).)

Synchrotron X-rays can be used to obtain highly detailed images of parts of the lung. However, micro-motion artifacts induced by such as cardiac motion impede quantitative visualization of the alveoli in the lungs. This paper proposes a method that applies a neural network for synchrotron X-ray Computed Tomography (CT) data to reconstruct the high-quality 3D structure of alveoli in intact mouse lungs at expiration, without needing ground-truth data. Our approach reconstructs the spatial sequence of CT images by using a deep-image prior with interpolated input latent variables, and in this way significantly enhances the images of alveolar structure compared with the prior art. The approach successfully visualizes 3D alveolar units of intact mouse lungs at expiration and enables us to measure the diameter of the alveoli. We believe that our approach helps to accurately visualize other living organs hampered by micro-motion., (© 2023. The Author(s).)

Spatiotemporal pH monitoring of single living cells across rigid cell and organelle membranes has been challenging, despite its significance in understanding cellular heterogeneity. Here, we developed a mechanically robust yet tolerably thin nanowire waveguide that enables in situ monitoring of pH dynamics at desired cellular compartments via direct optical communication. By chemically labeling fluorescein at one end of a poly(vinylbenzyl azide) nanowire, we continuously monitored pH variations of different compartments inside a living cell, successfully observing organelle-exclusive pH homeostasis and stimuli-selective pH regulations. Importantly, it was demonstrated for the first time that, during the mammalian cell cycle, the nucleus displays pH homeostasis in interphase but a tidal pH curve in the mitotic phase, implying the existence of independent pH-regulating activities by the nuclear envelope. The rapid and accurate local pH-reporting capability of our nanowire waveguide would be highly valuable for investigating cellular behaviors under diverse biological situations in living cells.

Psoriasis is a chronic skin inflammation caused by a dysfunctional immune system, which causes systemic inflammation in various organs and tissues. Due to the risk of systemic inflammation and recurrence of psoriasis, it is important to identify the critical targets in the pathogenesis of psoriasis and develop targeted therapeutics. Dimerized translationally controlled tumor protein (dTCTP) promotes immune cell activation as a pro-inflammatory cytokine and plays a role in developing allergic diseases such as asthma and rhinitis. Here, we sought to explore whether dTCTP and its inhibition contributed to the development and control of imiquimod (IMQ)-induced psoriasis. Topical application of IMQ inflamed the skin of the back and ear, increased inflammatory cytokines, and decreased regulatory T cell markers. Interestingly, TCTP was significantly increased in inflamed skin and immune cells such as T cells, B cells, and macrophages after IMQ treatment and was secreted into the serum to undergo dimerization. Extracellular dTCTP treatment selectively suppressed regulatory T (Treg) cells, not other effector T helper (Th) cells, and increased M1 macrophages. Moreover, dTCTP-binding peptide 2 (dTBP2), a dTCTP inhibitor peptide, effectively attenuated the systemic inflammatory responses, including Th17 cell response, and alleviated psoriatic skin inflammation. dTBP2 blocked dTCTP-mediated Treg suppression and stimulated the expression of Treg cell markers in the spleen and inflammatory skin lesions. These results suggest that dTCTP dysregulated immune balance through Treg suppression in psoriatic inflammation and that functional inhibition of dTCTP by dTBP2 maintained immune homeostasis and attenuated inflammatory skin diseases by expanding Treg cells., (Copyright © 2022 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Cyclooxygenase-2 (COX-2) expression is up-regulated in inflammatory tissues and many premalignant and malignant tumors. Assessment of COX-2 protein in vivo, therefore, promises to be a powerful strategy to distinguish pathologic cells from normal cells in a complex disease setting. Herein, we report the first redox-activatable COX-2 probe, fluorocoxib Q (FQ), for in vivo molecular imaging of pathogenesis. FQ inhibits COX-2 selectively in purified enzyme and cell-based assays. FQ exhibits extremely low fluorescence and displays time- and concentration-dependent fluorescence enhancement upon exposure to a redox environment. FQ enters the cells freely and binds to the COX-2 enzyme. FQ exhibits high circulation half-life and metabolic stability sufficient for target site accumulation and demonstrates COX-2-targeted uptake and retention in cancer cells and pathologic tissues. Once taken up, it undergoes redox-mediated transformation into a fluorescent compound fluorocoxib Q-H that results in high signal-to-noise contrast and differentiates pathologic tissues from non-pathologic tissues for real-time in vivo imaging.

The new Brain Imaging Beamline (BIB) of the Taiwan Photon Source (TPS) has been commissioned and opened to users. The BIB and in particular its endstation are designed to take advantage of bright unmonochromatized synchrotron X-rays and target fast 3D imaging, ∼1 ms exposure time plus very high ∼0.3 µm spatial resolution. A critical step in achieving the planned performances was the solution to the X-ray induced damaging problems of the detection system. High-energy photons were identified as their principal cause and were solved by combining tailored filters/attenuators and a high-energy cut-off mirror. This enabled the tomography acquisition throughput to reach >1 mm 3  min -1 , a critical performance for large-animal brain mapping and a vital mission of the beamline.

When a liquid drop impacts on a heated substrate, it can remain deposited, or violently boil in contact, or lift off with or without ever touching the surface. The latter is known as the Leidenfrost effect. The duration and area of the liquid-substrate contact are highly relevant for the heat transfer, as well as other effects such as corrosion. However, most experimental studies rely on side view imaging to determine contact times, and those are often mixed with the time until the drop lifts off from the substrate. Here, we develop and validate a reliable method of contact time determination using high-speed X-ray imaging and total internal reflection imaging. We exemplarily compare contact and lift-off times on flat silicon and sapphire substrates. We show that drops can rebound even without formation of a complete vapor layer, with a wide range of lift-off times. On sapphire, we find a local minimum of lift-off times that is much shorter than expected from capillary rebound in the comparatively low-temperature regime of transition boiling/thermal atomization. We elucidate the underlying mechanism related to spontaneous rupture of the lamella and receding of the contact area.

We elucidate the evolution of the entrained air in drop impact on a wide range of liquids, using ultrafast X-ray phase-contrast imaging. We elaborate the retraction mechanism of the entrapped air film in terms of liquid viscosity. We found the criterion for deciding if the entrapped air evolves into single or double bubbles, as determined by competition among inertia, capillarity, and viscosity. Low viscosity and low surface tension induce a small daughter droplet encapsulated by a larger air shell bubble, forming an antibubble. We demonstrate a phase diagram for air evolution regarding hydrodynamics.

Microbubbles have been used as a soft template to produce hollow structures for diverse applications in chemistry, materials science, and biomedicine. It is a challenge, however, to control their size and position at single-entity level. We report on an on-demand method to produce and place a single microbubble with programmed size and position. The method exploits scanning an electrolyte-filled micropipette to place a hydrogen (H 2 ) bubble, generated by water electrolysis, on the desired position. The bubble growth is self-limited after the bubble size fits to the pipet aperture, yielding well-controlled bubble size. The bubble growth dynamics within the pipet is successfully investigated by a methodology that combines phase-contrast X-ray imaging and electric-current measurement. We show that the microbubbles, accurately controlled in size and position, can be used for the fabrication of various polypyrrole microcontainer arrays. We expect the scanning-pipet strategy could be generalized for manipulating various soft materials at will.

Dynamic wetting behaviors on soft solids are important to interpret complex biological processes from cell-substrate interactions. Despite intensive research studies over the past half-century, the underlying mechanisms of spreading behaviors are not clearly understood. The most interesting feature of wetting on soft matter is the formation of a "wetting ridge", a surface deformation by a competition between elasticity and capillarity. Dynamics of the wetting ridge formed at the three-phase contact line underlies the dynamic wetting behaviors, but remains largely unexplored mostly due to limitations in indirect observation. Here, we directly visualize wetting ridge dynamics during continuous- and stick-slip motions on a viscoelastic surface using X-ray microscopy. Strikingly, we discover that the ridge spreads spontaneously during stick and triggers contact line depinning (stick-to-slip transition) by changing the ridge geometry which weakens the contact line pinning. Finally, we clarify 'viscoelastic-braking', 'stick-slipping', and 'stick-breaking' spreading behaviors through the ridge dynamics. In stick-breaking, no ridge-spreading occurs and contact line pinning (hysteresis) is enhanced by cusp-bending while preserving a microscopic equilibrium at the ridge tip. We have furthered the understanding of spreading behaviors on soft solids and demonstrated the value of X-ray microscopy in elucidating various dynamic wetting behaviors on soft solids as well as puzzling biological issues.

Background: Preventing mother to child transmission of chronic hepatitis B infection in the setting of a high maternal viral load is challenging. The idea has emerged from antepartum tenofovir treatment with combination immunoprophylaxis., Aims: To demonstrate the efficacy and safety of tenofovir to prevent mother to child transmission of hepatitis B virus., Methods: PubMed, EMBASE, and Cochrane databases were searched through August 16, 2016. Comparative trials of second or third trimester tenofovir administration vs. controls for patients with chronic hepatitis B infection and non-comparative case series assessing mother to child transmission rates and evaluating maternal and foetal safety outcomes were included., Results: Ten studies (one randomised controlled trial, four non-randomised controlled trials and five case series) that enrolled 733 women were included. The pooled results from comparative trials (599 pregnancies) showed that tenofovir significantly reduced the risk of infant hepatitis B surface antigen seropositivity by 77% (odds ratio=0.23, 95% confidence intervals=0.10-0.52, P=.0004) without heterogeneity (I 2 =0%). In the case series analysis (134 pregnancies), only two cases (1.5%) of mother to child transmission with extremely high maternal viral load and non-compliance to treatment were identified. Maternal and foetal safety parameters including congenital malformation and foetal death were re-assuring., Conclusions: For pregnant women with high hepatitis B virus DNA levels, tenofovir administration in the second or third trimester can prevent mother to child transmission when combined with hepatitis B immunoglobulin and the hepatitis B vaccine. Tenofovir is safe and tolerable for both the mother and foetus., (© 2017 John Wiley & Sons Ltd.)

The prognostic role of aberrant serum miRNA expression for predicting response to sorafenib treatment in advanced hepatocellular carcinoma (HCC) patients has not been well characterized. We aimed to identify specific serum miRNAs that are associated with positive radiologic responses or improved survival in sorafenib-treated HCC patients. miR-18a, miR-21, miR-139-5p, miR-221, miR-224, and miR-10b-3p, were selected for analysis. Serum samples from 24 patients with advanced stage HCC and 25 patients with liver cirrhosis (LC) were analyzed. All of the miRNAs except miR-21 were found to be upregulated in serum samples from HCC patients. None of the miRNAs assayed differed significantly in terms of expression between the responder and non-responder groups among HCC patients. However, miR-10b-3p levels were significantly higher in the subgroup of HCC patients with worse overall survival (fold change = 5.8, P = 0.008). Serum miRNA-10b-3p was upregulated in the presence of macrovascular invasion (MVI), and those with higher serum miRNA-10b-3p had significantly shorter survival during treatment (P = 0.042). Although no single serum miRNA was predictive of response to sorafenib treatment, analysis of serum miR-10b-3p levels may be valuable for diagnosis of HCC and prediction of survival of sorafenib-treated patients., Competing Interests: The authors have no potential conflicts of interest to disclose.

The fountain pen approach, as a means for transferring materials to substrates, has shown numerous incarnations in recent years for creating 2D micro/nanopatterns and even generating 3D free-form nanostructures using a variety of material "inks". While the idea of filled reservoirs used to deliver material to a substrate via a capillary remains unchanged since antiquity, the advent of precise micromanipulation systems and functional material "inks" allows the extension of this mechanism to more high-tech applications. Herein, the recent growth in meniscus guided fountain pen approaches for benchtop micro/nanofabrication, which has occurred in the last decade, is discussed. Particular attention is given to the theory, equipment, and experimentation encompassing this unique direct writing approach. A detailed exploration of the diverse ink systems and functional device applications borne from this strategy is put forth to reveal its rapid expansion to a broad range of scientific and engineering disciplines. As such, this informative review is provided for researchers considering adoption of this recent advancement of a familiar technology., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Follicular helper T (Tfh) cells are recently characterized subset of helper T cells, which are initially found in the germinal centers of B cell follicles. The major role of Tfh cells is helping B cell activation and antibody production during humoral immunity. Recently, blood Tfh cells were shown to be associated with autoimmune diseases, such as systemic lupus erythematosus, rheumatoid arthritis, bullous pemphigoid and psoriasis. There is only one study which investigated Tfh cells in psoriasis patients. Therefore, in this study, we evaluated and analyzed blood Tfh cells in Korean patients with psoriasis. A total of 28 psoriasis patients and 16 healthy controls were enrolled. The frequency and absolute number of CXCR5(+)PD-1(+) Tfh cells were decreased in patients with psoriasis compared to healthy controls. CD4(+)CXCR5(+) T cells and CXCR5(+)ICOS(+) Tfh cells did not show differences. The frequency and absolute number of CXCR5(+)PD-1(+) Tfh cells in psoriasis patients negatively correlated with erythrocyte sedimentation rate and positively correlated with disease duration. The absolute number of CXCR5(+)ICOS(+) Tfh cells also showed positive correlation with disease duration. However, the subpopulations of Tfh cells did not correlate with Psoriasis Area and Severity Index. Serum interleukin-21 level was significantly increased in psoriasis patients compared to healthy controls, however, its level did not correlate with clinical and experimental parameters of psoriasis patients. These findings suggest the decreased function of Tfh cells in psoriasis, which could result in attenuated B cell immune responses in the pathogenesis of psoriasis. However, further investigations are necessary to confirm the function of Tfh cells in psoriasis vulgaris.

Quantitative probing of Cu(2+) ions naturally present in single living cells is realized by developing a quantum-dot-embedded nanowire-waveguide probe. The intracellular Cu(2+) ion concentration is quantified by direct monitoring of photoluminescence quenching during the insertion of the nanowire in a living neuron. The measured intracellular Cu(2+) ion concentration is 3.34 ± 1.04 × 10(-6) m (mean ± s.e.m.) in single hippocampal neurons., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Quantitative probing of the Cu(2+) ions naturally present in single living cells is accomplished by a probe made from a quantum-dot-embedded-nanowire waveguide. After inserting the active nanowire-based waveguide probe into single living cells, J. H. Je and co-workers directly observe photoluminescence (PL) quenching of the embedded quantum dots by the Cu(2+) ions diffused into the probe as described on page 4071. This results in quantitative measurement of intracellular Cu(2+) ions., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

X-ray irradiation is shown to trigger the deposition of Cu from solution, at room temperature, on a wide variety of insulating substrates: glass, passivated Si, TiN/Ti/SiO2/Si and photoresists like PMMA and SU-8. The process is suitable for patterning and the products can be used as seeds for electroplating of thicker overlayers.

A vortex is a flow phenomenon that is very commonly observed in nature. More than a century, a vortex ring that forms during drop splashing has caught the attention of many scientists due to its importance in understanding fluid mixing and mass transport processes. However, the origin of the vortices and their dynamics remain unclear, mostly due to the lack of appropriate visualization methods. Here, with ultrafast X-ray phase-contrast imaging, we show that the formation of vortex rings originates from the energy transfer by capillary waves generated at the moment of the drop impact. Interestingly, we find a row of vortex rings along the drop wall, as demonstrated by a phase diagram established here, with different power-law dependencies of the angular velocities on the Reynolds number. These results provide important insight that allows understanding and modelling any type of vortex rings in nature, beyond just vortex rings during drop splashing.

Background: Langerhans cells (LCs) are skin-resident dendritic cells (DCs) that orchestrate skin immunity. CCCTC-binding factor (CTCF) is a highly conserved DNA-binding protein that regulates higher-order chromatin organization and is involved in various gene regulation processes., Objective: We sought to clarify a possible role for CTCF in LC homeostasis and function in vivo., Methods: We used a conditional gene deletion mouse system to generate DC- and LC-specific CTCF-ablated mice. Short hairpin RNA-mediated RNA interference was used to silence CTCF expression in human monocyte-derived Langerhans cells. DC populations were assessed by using flow cytometry and immunofluorescence. Gene expression arrays were performed to identify genes regulated by CTCF in LCs. Contact hypersensitivity and epicutaneous sensitization responses were measured to examine the functional significance of CTCF ablation., Results: DC-specific CTCF deletion led to a reduced pool of systemic DCs, with LCs most severely affected. Decreases in epidermal LC numbers were specifically associated with self-turnover defects. Interestingly, CTCF-deficient LCs demonstrated impaired migration out of the epidermis. Whole-transcriptome analyses revealed that genes that promoted cell adhesion were highly expressed, but CCR7 was downregulated in CTCF-depleted LCs. Hapten-induced contact hypersensitivity responses were more sustained in LC-specific CTCF-deficient mice, whereas epicutaneous sensitization to protein antigen was attenuated, indicating that CTCF-dependent LC homeostasis is required for optimal immune function of LCs in a context-dependent manner., Conclusion: Our results show that CTCF positively regulates the homeostatic pool and the efficient emigration of LCs, which are required for modulating the functional immune network of the skin., (Copyright © 2015 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.)

Psoriatic keratinocytes are one of the key components that amplify and maintain chronic inflammation. We hypothesized that lack of proper regulatory functions of keratinocytes can be responsible for chronic inflammation in psoriasis. Programmed death-ligands (PD-L) 1, 2 are expressed on keratinocytes, and expressions by nonlymphoid cells are important for mediating peripheral T cell tolerance. In our study, we investigated whether PD-L1, 2 expressions are altered in keratinocytes of psoriatic epidermis compared to normal epidermis. Epidermis was separated and analyzed for PD-L1, 2 expressions in mRNA and protein levels. Immunohistochemical stainings were done in skin biopsy samples from psoriasis, normal skin, allergic contact dermatitis (ACD), pityriasis rosea (PR) and lichen planus (LP). Expressions of PD-L1, 2 mRNA levels were significantly decreased in psoriatic epidermis compared to normal epidermis. In protein levels, PD-L1 expression was significantly decreased in psoriatic epidermis. However, PD-L2 expression was not detected in both normal and psoriatic epidermis. Immunohistochemical stainings revealed significantly less PD-L1 expression in psoriatic epidermis compared to normal epidermis. Even compared to other cutaneous inflammatory diseases, psoriatic epidermis showed less expression than ACD, PR and LP. PD-L2 expression was minimally detected in normal epidermis and not in psoriatic epidermis, but its expression was increased in ACD, PR and LP. In conclusion, we demonstrated that PD-L1, 2 are decreased in psoriatic epidermis in mRNA and protein levels. In addition, we showed that their expression was significantly lower than other inflammatory skin diseases. We suggest that decreased expression of PD-L1, 2 on psoriatic epidermis can contribute to its chronic unregulated inflammatory characteristics.

The dendritic planarity of Purkinje cells is critical for cerebellar circuit formation. In the absence of Crk and CrkL, the Reelin pathway does not function resulting in partial Purkinje cell migration and defective dendritogenesis. However, the relationships among Purkinje cell migration, dendritic development and Reelin signaling have not been clearly delineated. Here, we use synchrotron X-ray microscopy to obtain 3-D images of Golgi-stained Purkinje cell dendrites. Purkinje cells that failed to migrate completely exhibited conical dendrites with abnormal 3-D arborization and reduced dendritic complexity. Furthermore, their spines were fewer in number with a distorted morphology. In contrast, Purkinje cells that migrated successfully displayed planar dendritic and spine morphologies similar to normal cells, despite reduced dendritic complexity. These results indicate that, during cerebellar formation, Purkinje cells migrate into an environment that supports development of dendritic planarity and spine formation. While Reelin signaling is important for the migration process, it does not make a direct major contribution to dendrite formation.

The nematode Caenorhabditis elegans is a widely used model for genetic dissection of animal behaviors. Despite extensive technical advances in imaging methods, it remains challenging to visualize and quantify C. elegans behaviors in three-dimensional (3-D) natural environments. Here we developed an innovative 3-D imaging method that enables quantification of C. elegans behavior in 3-D environments. Furthermore, for the first time, we characterized 3-D-specific behavioral phenotypes of mutant worms that have defects in head movement or mechanosensation. This approach allowed us to reveal previously unknown functions of genes in behavioral regulation. We expect that our 3-D imaging method will facilitate new investigations into genetic basis of animal behaviors in natural 3-D environments.

A single photomechanical supramolecular nanowire actuator with an azobenzene-containing 1,3,5-tricarboxamide derivative is developed by employing a direct writing method. Single nanowires display photoinduced reversible bending and the bending behavior follows first-order kinetics associated with azobenzene photoisomerization. A wireless photomechanical nanowire tweezers that remotely manipulates a single micro-particle is also demonstrated.

A simple direct-writing technique can be used to fabricate a stretchable UV-vis-NIR nanowire photodetector (NWPD) consisting of PbS quantum dot (QD)-poly(3-hexylthiopehene) (P3HT) hybrid NWs. The hybrid NWPD shows superior sensitivity and response speed in the UV-vis to NIR range. The stretchable UV-vis-NIR NWPD shows a nearly identical photoresponse under extreme (up to 100%) and repeated (up to 100 cycles) stretching conditions., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Despite nearly a half century of studies, it has not been fully understood how pulmonary alveoli, the elementary gas exchange units in mammalian lungs, inflate and deflate during respiration. Understanding alveolar dynamics is crucial for treating patients with pulmonary diseases. In-vivo, real-time visualization of the alveoli during respiration has been hampered by active lung movement. Previous studies have been therefore limited to alveoli at lung apices or subpleural alveoli under open thorax conditions. Here we report direct and real-time visualization of alveoli of live intact mice during respiration using tracking X-ray microscopy. Our studies, for the first time, determine the alveolar size of normal mice in respiration without positive end expiratory pressure as 58 ± 14 (mean ± s.d.) μm on average, accurately measured in the lung bases as well as the apices. Individual alveoli of normal lungs clearly show heterogeneous inflation from zero to ~25% (6.7 ± 4.7% (mean ± s.d.)) in size. The degree of inflation is higher in the lung bases (8.7 ± 4.3% (mean ± s.d.)) than in the apices (5.7 ± 3.2% (mean ± s.d.)). The fraction of the total tidal volume allocated for alveolar inflation is 34 ± 3.8% (mean ± s.e.m). This study contributes to the better understanding of alveolar dynamics and helps to develop potential treatment options for pulmonary diseases.

While imported falciparum malaria has been increasingly reported in recent years in Korea, clinicians have difficulties in making a clinical diagnosis as well as in having accessibility to effective anti-malarial agents. Here we describe an unusual case of imported falciparum malaria with severe hemolytic anemia lasting over 2 weeks, clinically mimicking a coinfection with babesiosis. A 48-year old Korean man was diagnosed with severe falciparum malaria in France after traveling to the Republic of Benin, West Africa. He received a 1-day course of intravenous artesunate and a 7-day course of Malarone (atovaquone/proguanil) with supportive hemodialysis. Coming back to Korea 5 days after discharge, he was readmitted due to recurrent fever, and further treated with Malarone for 3 days. Both the peripheral blood smears and PCR test were positive for Plasmodium falciparum. However, he had prolonged severe hemolytic anemia (Hb 5.6 g/dl). Therefore, 10 days after the hospitalization, Babesia was considered to be potentially coinfected. A 7-day course of Malarone and azithromycin was empirically started. He became afebrile within 3 days of this babesiosis treatment, and hemolytic anemia profiles began to improve at the completion of the treatment. He has remained stable since his discharge. Unexpectedly, the PCR assays failed to detect DNA of Babesia spp. from blood. In addition, during the retrospective review of the case, the artesunate-induced delayed hemolytic anemia was considered as an alternative cause of the unexplained hemolytic anemia.

One of the most questionable issues in wetting is the force balance that includes the vertical component of liquid surface tension. On soft solids, the vertical component leads to a microscopic protrusion of the contact line, that is, a 'wetting ridge'. The wetting principle determining the tip geometry of the ridge is at the heart of the issues over the past half century. Here we reveal a universal wetting principle from the ridge tips directly visualized with high spatio-temporal resolution of X-ray microscopy. We find that the cusp of the ridge is bent with an asymmetric tip, whose geometry is invariant during ridge growth or by surface softness. This singular asymmetry is deduced by linking the macroscopic and microscopic contact angles to Young and Neuman laws, respectively. Our finding shows that this dual-scale approach would be contributable to a general framework in elastowetting, and give hints to issues in cell-substrate interaction and elasto-capillary problems.

Light-emitting conjugated polymer nanowires are vertically grown and remotely manipulated into a freestanding straight or curved structure in three-dimension. This approach enabled us to eliminate substrate coupling, a critical issue in nanowire photonics in the past decade. We for the first time accomplished characterization of propagation and bending losses of nanowires completely decoupled from a substrate.

Four-dimensional imaging, which indicates imaging in three spatial dimensions as a function of time, provides useful evidence to investigate the interactions of rising bubbles. However, this has been largely unexplored for microbubbles, mostly due to problems associated with strong light scattering and shallow depth of field in optical imaging. Here, tracking x-ray microtomography is used to visualize rising microbubbles in four dimensions. Bubbles are tracked by moving the cell to account for their rise velocity. The sizes, shapes, time-dependent positions, and velocities of individual rising microbubbles are clearly identified, despite substantial overlaps between bubbles in the field of view. Our tracking x-ray microtomography affords opportunities for understanding bubble-bubble (or particle) interactions at microscales - important in various fields such as microfluidics, biomechanics, and floatation.

We report for the first time single nanowires (NWs) with ambipolar (positive/negative) photoresponse that changes sign depending on the illumination wavelength. The single NWs were grown by the meniscus-guided method using inorganic (ZnO nanoparticles)-organic (PEDOT:PSS) hybrid materials. The ambipolar photoresponse of the single NWs enabled us to develop an unprecedented spectrum-discriminating NW photodetector array.

Dried roots of Gastrodia elata have traditionally been used in Korean medicine for the treatment of neurological disorders such as scotodinia, paralysis, and epilepsy. In our study, we attempted to investigate the neuroprotective effects of methanol extract from G. elata (MEGE) against glutamate-mediated oxidative stress and to explore underlying neuroprotective mechanisms. Analyses for cell viability, lactate dehydrogenase (LDH), flow cytometry, Western blot, and reactive oxygen species (ROS) were performed in HT22 hippocampal cells. Pretreatment with MEGE resulted in a potent neuroprotective effect against oxidative glutamate toxicity and these effects were exerted mainly by the abrogation of glutamate-induced apoptotic death. Treatment with glutamate resulted in a significant expression of both phosphorylated p38 and dephosphorylated phosphatidylinositol-3-kinase (PI3K). However, pretreatment with MEGE resulted in the inhibition of these expressions. In the inhibitor studies, treatment with PI3K inhibitor LY294002 resulted in the abrogation of the neuroprotective effect of MEGE. In addition, pretreatment with MEGE also resulted in the suppression of the glutamate-induced production of ROS. Treatment with MEGE and anti-oxidant N-acetyl-L-cysteine (NAC) resulted in the enhanced phosphorylation of both PI3K and cAMP responsive element binding protein (CREB), and, in particular, treatment with MEGE resulted in significantly enhanced expression of mature brain-derived neurotrophic factor (BDNF). These results suggest that the extract from G. elata mainly exerted neuroprotective effects through the up-regulation of the PI3K signaling pathway in association with BDNF and may be a useful therapeutic agent for treatment of oxidative neuronal death.

Reactive oxygen species (ROS) are produced by dendritic cells (DCs) during antigen presentation in contact hypersensitivity (CHS). ROS cause a number of non-enzymatic protein modifications, such as carbonylation. Carbonylated proteins in DCs in response to hapten have not been fully identified yet. To identify the proteins carbonylated by ROS, murine epidermis-derived DC line XS106 was challenged with a hapten, 2,4,6-trinitrobenzene sulphonic acid (TNBS). MALDI-TOF analysis revealed that heat-shock protein 70 (HSP70) was one of the carbonylated proteins induced by TNBS. To verify the role of HSP70 in TNBS-treated XS106 cell, we fused protein transduction domain (PTD) with HSP70 to facilitate protein delivery into the cell. The transfected fusion protein HSP70 within the cell caused transient increase of the cellular level of HSP70. Transient increase of HSP70 level in XS-106 DCs resulted in inhibition of ROS production, carbonylation of HSP70, p38 MAPK activation and subsequently IL-12 secretion. To investigate the effects of PTD-HSP70 in vivo, ear-swelling experiments with 2,4,6-trinitro-1-chlorobenzene (TNCB) were performed in BALB/c mice. Pretreatment of PTD-HSP70 reduced the CHS response to TNCB in vivo. We report here that carbonylation of HSP70 by ROS is associated with the pathogenesis of CHS, suggesting possibility of HSP70-targeting therapy in CHS., (© 2013 John Wiley & Sons Ltd.)

Numerous cell types have shown a remarkable ability to detect and move along gradients in stiffness of an underlying substrate--a process known as durotaxis. The mechanisms underlying durotaxis are still unresolved, but generally believed to involve active sensing and locomotion. Here, we show that simple liquid droplets also undergo durotaxis. By modulating substrate stiffness, we obtain fine control of droplet position on soft, flat substrates. Unlike other control mechanisms, droplet durotaxis works without imposing chemical, thermal, electrical, or topographical gradients. We show that droplet durotaxis can be used to create large-scale droplet patterns and is potentially useful for many applications, such as microfluidics, thermal control, and microfabrication.

Our experimental results demonstrate that full-field hard-X-ray microscopy is finally able to investigate the internal structure of cells in tissues. This result was made possible by three main factors: the use of a coherent (synchrotron) source of X-rays, the exploitation of contrast mechanisms based on the real part of the refractive index and the magnification provided by high-resolution Fresnel zone-plate objectives. We specifically obtained high-quality microradiographs of human and mouse cells with 29 nm Rayleigh spatial resolution and verified that tomographic reconstruction could be implemented with a final resolution level suitable for subcellular features. We also demonstrated that a phase retrieval method based on a wave propagation algorithm could yield good subcellular images starting from a series of defocused microradiographs. The concluding discussion compares cellular and subcellular hard-X-ray microradiology with other techniques and evaluates its potential impact on biomedical research., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Colloidal particles suspended in a fluid usually inhibit complete wetting of the fluid on a solid surface and cause pinning of the contact line, known as self-pinning. We show differences in spreading and drying behaviors of pure and colloidal droplets using optical and confocal imaging methods. These differences come from spreading inhibition by colloids confined at a contact line. We propose a self-pinning mechanism based on spreading inhibition by colloids. We find a good agreement between the mechanism and the experimental result taken by directly tracking individual colloids near the contact lines of evaporating colloidal droplets.

Colloidal droplets including micro- and nanoparticles generally leave a ringlike stain, called the "coffee ring," after evaporation. We show that fingering emerges during evaporation inside the coffee ring, resulting from a bidispersed colloidal mixture of micro- and nanoparticles. Microscopic observations suggest that finger formation is driven by competition between the coffee-ring and Marangoni effects, especially when the inward Marangoni flow is overwhelmed by the outward coffee-ring flow. This finding could help to understand the variety of the final deposition patterns of colloidal droplets.

The manner in which the nervous system regulates animal behaviors in natural environments is a fundamental issue in biology. To address this question, C. elegans has been widely used as a model animal for the analysis of various animal behaviors. Previous behavioral assays have been limited to two-dimensional (2-D) environments, confining the worm motion to a planar substrate that does not reflect three-dimensional (3-D) natural environments such as rotting fruits or soil. Here, we develop a 3-D worm tracker (3DWT) for freely moving C. elegans in 3-D environments, based on a stereoscopic configuration. The 3DWT provides us with a quantitative trajectory, including the position and movement direction of the worm in 3-D. The 3DWT is also capable of recording and visualizing postures of the moving worm in 3-D, which are more complex than those in 2-D. Our 3DWT affords new opportunities for understanding the nervous system function that regulates animal behaviors in natural 3-D environments.

Here we report a tracking X-ray microscopy (TrXM) as a novel methodology by using upper right lung apices alveoli in live intact mice. By enabling tracking of individual alveolar movements during respiration, TrXM identifies alveolar dynamics: individual alveoli in the upper lung apices show a small size increment as 4.9 ± 0.4% (mean ± s.e.m.) during respiration while their shapes look almost invariant. TrXM analysis in alveolar dynamics would be significant for better understanding of alveolar-based diseases, for instance, ventilator induced lung injury (VILI) in acute respiratory distress syndrome (ARDS).

When a liquid drop impacts a solid surface, air is generally entrapped underneath. Using ultrafast x-ray phase-contrast imaging, we directly visualized the profile of an entrapped air film and its evolution into a bubble during drop impact. We identified a complicated evolution process that consists of three stages: inertial retraction of the air film, contraction of the top air surface into a bubble, and pinch-off of a daughter droplet inside the bubble. Energy transfer during retraction drives the contraction and pinch-off of a daughter droplet. The wettability of the solid surface affects the detachment of the bubble, suggesting a method for bubble elimination in many drop-impact applications.

A fast microtomography system for high-resolution high-speed imaging has been developed using bright monochromatic x-rays at the BL29XU beamline of SPring-8. The shortest scan time for microtomography we attained was 0.25 s in 1.25 μm effective pixel size by combining the bright monochromatic x-rays, a fast rotating sample stage, and a high performance x-ray imaging detector. The feasibility of the tomography system was successfully demonstrated by visualization of rising bubbles in a viscous liquid, an interesting issue in multiphase flow physics. This system also provides a high spatial (a measurable feature size of 300 nm) or a very high temporal (9.8 μs) resolution in radiographs.