Successful integration of advanced semiconductor devices with biological systems will accelerate basic scientific discoveries and their translation into clinical technologies. In neuroscience ...generally, and in optogenetics in particular, the ability to insert light sources, detectors, sensors, and other components into precise locations of the deep brain yields versatile and important capabilities. Here, we introduce an injectable class of cellular-scale optoelectronics that offers such features, with examples of unmatched operational modes in optogenetics, including completely wireless and programmed complex behavioral control over freely moving animals. The ability of these ultrathin, mechanically compliant, biocompatible devices to afford minimally invasive operation in the soft tissues of the mammalian brain foreshadow applications in other organ systems, with potential for broad utility in biomédical science and engineering.
A method for forming efficient, ultrathin GaN light‐emitting diodes (LEDs) and for their assembly onto foreign substances is reported. The LEDs have lateral dimensions ranging from ∼1 mm × 1 mm to ...∼25 μm × 25 μm. Quantitative experimental and theoretical studies show the benefits of small device geometry on thermal management, for both continuous and pulsed‐mode operation, the latter of which suggests the potential use of these technologies in bio‐integrated contexts.
Spatial light modulators are essential optical elements in applications that require the ability to regulate the amplitude, phase and polarization of light, such as digital holography, optical ...communications and biomedical imaging. With the push towards miniaturization of optical components, static metasurfaces are used as competent alternatives. These evolved to active metasurfaces in which light-wavefront manipulation can be done in a time-dependent fashion. The active metasurfaces reported so far, however, still show incomplete phase modulation (below 360°). Here we present an all-solid-state, electrically tunable and reflective metasurface array that can generate a specific phase or a continuous sweep between 0 and 360° at an estimated rate of 5.4 MHz while independently adjusting the amplitude. The metasurface features 550 individually addressable nanoresonators in a 250 × 250 μm
area with no micromechanical elements or liquid crystals. A key feature of our design is the presence of two independent control parameters (top and bottom gate voltages) in each nanoresonator, which are used to adjust the real and imaginary parts of the reflection coefficient independently. To demonstrate this array's use in light detection and ranging, we performed a three-dimensional depth scan of an emulated street scene that consisted of a model car and a human figure up to a distance of 4.7 m.
Neurofibrillary tangles (NFTs), composed of truncated and hyperphosphorylated tau, are a common feature of numerous aging-related neurodegenerative diseases, including Alzheimer's disease (AD). ...However, the molecular mechanisms mediating tau truncation and aggregation during aging remain elusive. Here we show that asparagine endopeptidase (AEP), a lysosomal cysteine proteinase, is activated during aging and proteolytically degrades tau, abolishes its microtubule assembly function, induces tau aggregation and triggers neurodegeneration. AEP is upregulated and active during aging and is activated in human AD brain and tau P301S-transgenic mice with synaptic pathology and behavioral impairments, leading to tau truncation in NFTs. Tau P301S-transgenic mice with deletion of the gene encoding AEP show substantially reduced tau hyperphosphorylation, less synapse loss and rescue of impaired hippocampal synaptic function and cognitive deficits. Mice infected with adeno-associated virus encoding an uncleavable tau mutant showed attenuated pathological and behavioral defects compared to mice injected with adeno-associated virus encoding tau P301S. Together, these observations indicate that AEP acts as a crucial mediator of tau-related clinical and neuropathological changes. Inhibition of AEP may be therapeutically useful for treating tau-mediated neurodegenerative diseases.
One of the holy grails in biomedical imaging technology is to achieve accurate imaging of biological targets. The development of sophisticated instrumentation and the use of contrast agents have ...improved the accuracy of biomedical imaging. However, the issue of false imaging remains a problem. Here, we developed a dual-mode artifact filtering nanoparticle imaging agent (AFIA) that comprises a combination of paramagnetic and superparamagnetic nanomaterials. This AFIA has the ability to perform “AND logic gate” algorithm to eliminate false errors (artifacts) from the raw images to enhance accuracy of the MRI. We confirm the artifact filtering capability of AFIA in MRI phantoms and further demonstrate that artifact-free imaging of stem cell migration is possible in vivo.
Ubiquitin‐specific protease 4 (USP4) is highly overexpressed in colon cancer and acts as a potent protooncogenic protein by deubiquitinating β‐catenin. However, its prominent roles in tumor formation ...and migration in cancer cells are not fully understood by its deubiquitinating enzyme (DUB) activity on β‐catenin. Thus, we investigated an additional role of USP4 in cancer. In this study, we identified cortactin (CTTN), an actin‐binding protein involved in the regulation of cytoskeleton dynamics and a potential prognostic marker for cancers, as a new cellular interacting partner of USP4 from proximal labeling of HCT116 cells. Additionally, the role of USP4 in CTTN activation and promotion of cell dynamics and migration was investigated in HCT116 cells. We confirmed that interacting of USP4 with CTTN increased cell movement. This finding was supported by the fact that USP4 overexpression in HCT116 cells with reduced expression of CTTN was insufficient to promote cell migration. Additionally, we observed that USP4 overexpression led to a significant increase in CTTN phosphorylation, which is a requisite mechanism for cell migration, by regulating Src/focal adhesion kinase (FAK) binding to CTTN and its activation. Our results suggest that USP4 plays a dual role in cancer progression, including stabilization of β‐catenin as a DUB and interaction with CTTN to promote cell dynamics by inducing CTTN phosphorylation. Therefore, this study demonstrates that USP4 is important for cancer progression and is a good target for treating or preventing cancer.
A summary scheme of this study. CTTN interacts and forms a complex with the Src‐FAK complex. However, USP4 overexpression can induce an increase in CTTN phosphorylation and dissociation of the p‐CTTN from Src‐FAK‐CTTN‐USP4 complex, which promotes cell dynamics.
Brown patch caused by the basidiomycete fungus
is an economically important disease of cool-season turfgrasses. In order to manage the disease, different types of fungicides have been applied, but ...the negative impact of fungicides on the environment continues to rise. In this study, the beneficial bacteria
GH1-13 was characterized as a potential biocontrol agent to manage brown patch disease. The strain GH1-13 strongly inhibited the mycelial growth of turf pathogens including different anastomosis groups of
causing brown patch and large patch.
AG2-2(IIIB) hyphae were morphologically changed, and fungal cell death resulted from exposure to the strain GH1-13. In addition, the compatibility of fungicides with the bacterial strain, and the combined application of fungicide azoxystrobin and the strain in brown patch control on creeping bentgrass indicated that the strain could serve as a biocontrol agent. To develop strain-specific detection method, two unique genes from chromosome and plasmid of GH1-13 were found using pan-genome analysis of 364
strains. The unique gene from chromosome was successfully detected using both SYBR Green and TaqMan qPCR methods in bacterial DNA or soil DNA samples. This study suggests that application of GH1-13 offers an environmentally friendly approach
reducing fungicide application rates. Furthermore, the developed pipeline of strain-specific detection method could be a useful tool for detecting and studying the dynamics of specific biocontrol agents.
As a result of nuclear power plant accidents such as Chernobyl and Fukushima, and even their maintenance, the soil is contaminated due to the discharge of radioactive materials. Soil contaminated by ...Cs and other radioactive materials must be decontaminated so that the land can be reused as an industrial site or at least restored to a natural state. Accordingly, this study selected the soil washing method from among several available. In this study, water is used as a washing agent for the soil washing process while a flocculating agent is added to increase efficiency. It was found that when the flocculating agent was used, maximum removal rate being about 88%.
Radioactive substances released as nuclear power plant accident can contaminate soil in a wide area. Soil washing is used as decontamination technique for Cs-contaminated soil, which exhibits short ...processing time and maximization of Cs removal rate by applying flocculating agents. However, soil washing generates secondary waste in the form of sludge/slurry. In this context, proposed a method of pelletization and solidification of powdered waste to facilitate treatment/disposal of the Cs-contaminated fine soil (secondary waste). In addition, by characterizing the prepared waste form, it was examined whether waste form satisfies Waste Acceptance Criteria for disposal facilities in South Korea.
Background
The efficacy of stenting for right-sided malignant colonic obstruction is unknown. This study aimed to evaluate the safety, feasibility, and clinical benefits of self-expandable metallic ...stent insertion for right-sided malignant colonic obstruction.
Methods
Clinical data from patients who underwent right hemicolectomy for right colon cancer from January 2006 to July 2014 at three Korea University hospitals were retrospectively reviewed. A total of 39 patients who developed malignant obstruction in the right-sided colon were identified, and their data were analyzed.
Results
Stent insertion was attempted in 16 patients, and initial technical success was achieved in 14 patients (87.5 %). No stent-related immediate complications were reported. Complete relief from obstruction was achieved in all 14 patients. Twenty-five patients, including two patients who failed stenting, underwent emergency surgery. In the stent group, 93 % (13/14) of patients underwent elective laparoscopic surgery, and only one surgery was converted to an open procedure. All patients in the emergency group underwent emergency surgery within 24 h of admission. In the emergency group, only 12 % (3/25) of patients underwent laparoscopic surgery, with one surgery converted to an open procedure. All patients in both groups underwent either laparoscopy-assisted or open right/extended right hemicolectomy with primary anastomoses as the first operation. The operative times, retrieved lymph nodes, and pathologic stage did not differ between the two groups. Postoperative hospital stay (9.4 ± 3.4 days in the stent group vs. 12.4 ± 5.9 in the emergency group,
p
= 0.089) and time to resume oral food intake (3.2 ± 2.1 days in the stent group vs. 5.7 ± 3.4 in the emergency group,
p
= 0.019) were shorter in the stent group. And there were no significant differences in disease-free survival and overall survival between the two groups.
Conclusions
Stent insertion appears to be safe and feasible in patients with right-sided colonic malignant obstruction. It facilitates minimally invasive surgery and may result in better short-term surgical outcomes.
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