To use for GEKKO XII Module glass laser system, we have developed an oscillator system, which consists of a mode-locked YAG laser, a pulse selector, a pulse shaper, and controller circuits. The ...mode-locked YAG laser oscillates at a wavelength of 1.052μm and gives out-put energy of 10 μJ/pulse. The pulse width is variable in a range from 90ps to 1.4ns. The pulse selector switches out a single pulse from a mode-locked pulse train with 50% transmittance. The ratio of the energy of the selected pulse to that of the unselected prepalses is greater than 108. The pulse shaper is of a passive type. It produces a shaped pulse whose envelope is determined by the requirements for target compression experiments.
Mode locking and frequency tuning of a CW light-focusing Nd : glass laser called the SELFOC Nd : glass laser were achieved. Using an acoustooptic modulator having a modest degree of modulation (about ...3 percent), almost perfectly mode-locked pulses as short as 49 ps were obtained. Pulsewidth was measured with an intensity-correlation method using the second-harmonic generation in KDP. Most of the observed shapes of the intensity-correlation curves were in agreement with theories previously presented by several authors. When the laser was mode locked, the long-term averaged optical spectrum was observed to narrow considerably. Some experimental evidence that the CW SELFOC Nd:glass laser could be considered to have a homogeneously broadened line was also found. Frequency tuning was achieved by using a tilted etalon in a cavity. When a 50-μm-thick etalon was used, the tuning range was more than 40 Å. Pulses obtained from a frequency-tuned mode-locked laser were as short as about 100 ps.
High-harmonic generation in solids is a unique tool to investigate the electron dynamics in strong light fields. The systematic study in monolayer materials is required to deepen the insight into the ...fundamental mechanism of high-harmonic generation. Here we demonstrated nonperturbative high harmonics up to 18th order in monolayer transition metal dichalcogenides. We found the enhancement in the even-order high harmonics which is attributed to the resonance to the band nesting energy. The symmetry analysis shows that the valley polarization and anisotropic band structure lead to polarization of the high-harmonic radiation. The calculation based on the three-step model in solids revealed that the electron-hole polarization driven to the band nesting region should contribute to the high harmonic radiation, where the electrons and holes generated at neighboring lattice sites are taken into account. Our findings open the way for attosecond science with monolayer materials having widely tunable electronic structures.
Targeting the function of membrane transporters in cancer stemlike cells is a potential new therapeutic approach. Cystine‐glutamate antiporter xCT expressed in CD44 variant (CD44v)‐expressing cancer ...cells contributes to the resistance to oxidative stress as well as cancer therapy through promoting glutathione (GSH)‐mediated antioxidant defense. Amino acid transport by xCT might, thus, be a promising target for cancer treatment, whereas the determination factors for cancer cell sensitivity to xCT‐targeted therapy remain unclear. Here, we demonstrate that high expression of xCT and glutamine transporter ASCT2 is correlated with undifferentiated status and diminished along with cell differentiation in head and neck squamous cell carcinoma (HNSCC). The cytotoxicity of the xCT inhibitor sulfasalazine relies on ASCT2‐dependent glutamine uptake and glutamate dehydrogenase (GLUD)‐mediated α‐ketoglutarate (α‐KG) production. Metabolome analysis revealed that sulfasalazine treatment triggers the increase of glutamate‐derived tricarboxylic acid cycle intermediate α‐KG, in addition to the decrease of cysteine and GSH content. Furthermore, ablation of GLUD markedly reduced the sulfasalazine cytotoxicity in CD44v‐expressing stemlike HNSCC cells. Thus, xCT inhibition by sulfasalazine leads to the impairment of GSH synthesis and enhancement of mitochondrial metabolism, leading to reactive oxygen species (ROS) generation and, thereby, triggers oxidative damage. Our findings establish a rationale for the use of glutamine metabolism (glutaminolysis)‐related genes, including ASCT2 and GLUD, as biomarkers to predict the efficacy of xCT‐targeted therapy for heterogeneous HNSCC tumors.
Competition exists between xCT‐mediated cystine uptake and GLUD‐mediated alpha‐KG generation.
Sugar content is one of the most important quality traits of tomato. Cell wall invertase promotes sucrose unloading in the fruit by maintaining a gradient of sucrose concentration between source ...leaves and fruits, while invertase inhibitor (INVINH) regulates this process. In this study, knock-out of cell wall INVINH in tomato (SlINVINH1) was performed by genome editing using, CRISPR/Cas9 and Target-AID technologies. Most of the genome-edited lines set higher soluble solid content (SSC) fruit than the original cultivar 'Suzukoma', while fruit weight was different among the genome-edited lines. From these genome-edited lines, three lines (193-3, 199-2, and 247-2), whose SSC was significantly higher than 'Suzukoma' and fruit weight were almost the same as the original cultivar, were selected. The fruit weight and overall plant growth of the two lines were comparable to those of the original cultivar. In contrast, the fructose and glucose contents in the mature fruits of the two lines were significantly higher than those of the original cultivar. The mature fruits of genome edited line 193-3 showed the highest sugar content, and the fructose and glucose contents were 29% and 36% higher than that of the original cultivar, respectively. Whole genome sequence data showed no off-target mutations in the genome-edited lines. Non-target metabolome analysis of mature fruits revealed that fructose was the highest loading factor in principal component analysis (PCA) between the genome-edited line and the original cultivar, and no unexpected metabolites appeared in the genome-edited line. In this study, we succeeded in producing tomato lines with high sugar content without a decrease in fruit weight and deterioration of plant growth by knock-out of SlINVINH1 using genome editing technology. This study showed that functional disruption of SlINVINH1 is an effective approach to produce tomato cultivars with high sugar content.
Organisms have evolved under gravitational force, and many sense the direction of gravity by means of statoliths in specialized cells. In flowering plants, starch-accumulating plastids, known as ...amyloplasts, act as statoliths to facilitate downstream gravitropism. The gravity-sensing mechanism has long been considered a mechanosensing process by which amyloplasts transmit forces to intracellular structures, but the molecular mechanism underlying this has not been elucidated. We show here that LAZY1-LIKE (LZY) family proteins involved in statocyte gravity signaling associate with amyloplasts and the proximal plasma membrane. This results in polar localization according to the direction of gravity. We propose a gravity-sensing mechanism by which LZY translocation to the plasma membrane signals the direction of gravity by transmitting information on the position of amyloplasts.
Migrasomes are extracellular vesicles that form on the retraction fibers of migrating cells. In this study, we report the formation of migrasome‐like vesicles enriched in tetraspanin 4 and containing ...cytoplasmic components in response to hypoosmotic stress. When migrating cells were subjected to hypoosmotic stress, vesicles with a size distribution of 0.5 to 2 μm formed on the retraction fibers, and vanished in a few minutes. The vesicles are rich in cholesterol, and their number was reduced when cells were pretreated with lipoprotein‐deficient serum. The formation of migrasome‐like vesicles upon hypoosmotic stress may provide biophysical cues regarding the cellular response to this external stimulus in cells and tissues.
When migrating cells were subjected to hypoosmotic stress, the formation of migrasome‐like vesicles enriched in tetraspanin 4 and containing cytoplasmic components was observed. These vesicles are rich in cholesterol and their number is reduced when cells are pretreated with lipoprotein‐deficient serum.
Cage-like supramolecular assemblies called molecular cages, which possess attractive functions, have been prepared. Although biomolecule-based nanocages are required for biological/medical ...applications such as drug delivery systems, the majority of nanocages are constructed using aromatic compounds with lower biocompatibility and biodegradability. In this study, the construction of a peptide nanocage consisting of an oligoproline conjugate is demonstrated. The conjugate was easy to prepare and had high biocompatibility. The oligoproline moiety of the conjugate had a rigid, rod-like structure suitable for the backbone of the supramolecular nanocage. The conjugates self-assembled to form peptide nanocages with a huge inner cavity.
Gait parameters and gross motor function improve after 12 sessions of small-sized Hybrid Assistive Limb® (S-HAL) training in adult cerebral palsy (CP) patients. However, there are no reports on ...repetitive robot-assisted gait training using the newly developed very small-sized HAL (2S-HAL). This study aimed to examine the effect of using 2S-HAL on a pediatric CP patient.
The subject was an 11-year-old boy (height = 138 cm, weight = 30 kg) with spastic quadriplegia due to periventricular leukomalacia, with Gross Motor Function Classification System level IV. HAL training was performed for 2–4 sessions/week for 20 min/session (i.e., 4-week period with 12 sessions). Outcome measures were walking ability, gross motor function, Canadian Occupational Performance Measure (COPM), and Pediatric Evaluation of Disability Inventory measured before, after, and at 1, 2, and 3 months after HAL-assisted gait training.
After HAL intervention, gait speed, step length, cadence, 6-min walking distance (6MD), Gross Motor Function Measure (GMFM), and COPM increased and physiological cost index (PCI) declined compared to those before intervention.
The peaks of gait speed, step length, and cadence were 2 month, 1 month, and 3 month, respectively. 6MD, PCI, and GMFM at 1–3 months post-intervention were maintained. COPM peaked at 1 month post-intervention but remained higher than that before intervention.
This is the first report of repetitive intervention using 2S-HAL in a pediatric CP patient. Gait training using 2S-HAL may be effective in CP patients as it improves post-training walking ability and gross motor function.
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