Your browser doesn't support javascript.
loading
: 20 | 50 | 100
1 - 20 de 601
1.
Article En | MEDLINE | ID: mdl-38031151

OBJECTIVE: This study aimed to examine infantile outcomes at 3 years of age with selective fetal growth restriction (sFGR) Types II and III with isolated oligohydramnios who underwent fetoscopic laser photocoagulation (FLP). METHODS: This multicenter prospective cohort study included monochorionic diamniotic twins who underwent FLP for sFGR between 16 and 25 weeks of gestation. The indication for performing FLP was in cases of sFGR Type II or III with oligohydramnios, where the maximal vertical pocket was ≤2 cm among twins with FGR. This was done in the absence of a typical twin-twin transfusion syndrome diagnosis. The primary outcome was the intact survival (IS) rate of infants at the corrected age of 40 weeks and 3 years. IS at the corrected age of 40 weeks was defined as survival without grade III or IV intraventricular hemorrhage or cystic periventricular leukomalacia, and IS at 3 years of age was defined as survival without neurodevelopmental morbidity, including cerebral palsy, neurodevelopmental impairment with a total developmental quotient of ≤70, bilateral deafness, or bilateral blindness. RESULTS: Among 45 patients with sFGR, 30 (66.7%) were classified as having Type II and 15 (33.3%) as Type III sFGR. The prevalence of IS at the corrected age of 40 weeks was 51.1% (n=23) in FGR twins and 95.5% (n=42) in larger twins. The prevalence of IS at 3 years of age was 46.7% (n=21) in FGR twins and 86.4% (n=38) in larger twins. Among the 24 FGR twins who were not diagnosed with IS at 3 years of age, 91.7% (22 of 24 cases) suffered fetal or infantile demise other than miscarriage and neurodevelopmental impairment. All larger twins who were not diagnosed with IS at 3 years of age (n=6, 13.6%) had neurological morbidity, in addition to one case of miscarriage. CONCLUSIONS: FGR twins and larger twins, when subjected to FLP due to sFGR coupled with umbilical artery Doppler abnormalities and isolated oligohydramnios, exhibit low rates of neurological morbidity and low mortality, respectively. Therefore, FLP for Type II or III sFGR with oligohydramnios may be a feasible and preferable management option. This article is protected by copyright. All rights reserved.

2.
Sci Rep ; 13(1): 10292, 2023 Jun 25.
Article En | MEDLINE | ID: mdl-37357245

Synchrotron radiation, emitted by relativistic electrons traveling in a magnetic field, has poor temporal coherence. However, recent research has proved that time-domain interferometry experiments, which were thought to be enabled by only lasers of excellent temporal coherence, can be implemented with synchrotron radiation using a tandem undulator. The radiation generated by the tandem undulator comprises pairs of light wave packets, and the longitudinal coherence within a light wave packet pair is used to achieve time-domain interferometry. The time delay between two light wave packets, formed by a chicane for the electron trajectory, can be adjusted in the femtosecond range by a standard synchrotron technology. In this study, we show that frequency-domain spectra of the tandem undulator radiation exhibit fringe structures from which the time delay between a light wave packet pair can be determined with accuracy on the order of attoseconds. The feasibility and limitations of the frequency-domain interferometric determination of the time delay are examined.

3.
Sci Rep ; 13(1): 6142, 2023 Apr 15.
Article En | MEDLINE | ID: mdl-37061592

We present a new realization of the time-domain double-slit experiment with photoelectrons, demonstrating that spontaneous radiation from a bunch of relativistic electrons can be used to control the quantum interference of single-particles. The double-slit arrangement is realized by a pair of light wave packets with attosecond-controlled spacing, which is naturally included in the spontaneous radiation from two undulators in series. Photoelectrons emitted from helium atoms are observed in the energy-domain under the condition of detecting them one by one, and the stochastic buildup of the quantum interference pattern on a detector plane is recorded.

9.
Ultrasonics ; 98: 82-87, 2019 Sep.
Article En | MEDLINE | ID: mdl-31207475

A pulsed laser illuminates a target zone that causes rapid thermoelastic expansion, generating broadband high-frequency ultrasonic wave (photoacoustic wave, PA wave). We developed a PA microscopy (PAM) with a confocal area of laser and ultrasonic wave for applications in nondestructive testing (NDT). The synthetic aperture focusing technique (SAFT) is applied in the PAM for the three-dimensional (3D) imaging of interior flaws. Here, we report proof-of-concept experiments for the NDT of a subsurface flaw in a thin laminar material. Graphical abstract (a) shows a specimen of carbon-fiber-reinforced plastic (CFRP) with an artificial delamination. Here, it should be noted that the group velocity varies directionally due to the strong anisotropy of the CFRP specimen (see Graphical abstract (b)). By considering the group velocity distribution in the SAFT, the shape and location of the subsurface delamination were accurately estimated as shown in Graphical abstract (c). Coating the surface of the CFRP specimen with a light-absorbent material improved the amplitude of the PA wave. This finding showed that the signal-to-noise ratio of the waves scattered from the flaws can be improved.

10.
Cryo Letters ; 38(3): 250-256, 2017.
Article En | MEDLINE | ID: mdl-28767748

BACKGROUND: Hop powdery mildew (HPM), Podosphaera macularis, an important disease organism for hops, is an obligate parasite, requiring constant culture on living plant tissue for strain maintenance. OBJECTIVE: This study determined the parameters required to successfully cryopreserve HPM spores for the first time and reduce the need for constant culture. MATERIALS AND METHODS: Spores of an Oregon HPM strain, OSU C-100 were desiccated over silica gel for 2-10 h to determine the spore moisture content (MC). Regrowth of the hyphae before and after drying and liquid nitrogen exposure was determined on glass slides and leaf discs of several susceptible hop cultivars. A second mixture of strains was later tested with the protocol. RESULTS: Desiccation to an optimal 2-3 percent MC produced hyphal growth on slides and infection of leaf discs. The OSU C-100 HPM spore strain required 8-10 h desiccation to reach 2-3 percent MC while the mixed strains required 6-8 h due to slightly different MC when collected. CONCLUSION: HPM strains should be placed in cryovials, dried to 2-3 percent MC over silica gel, cryopreserved by direct immersion in liquid nitrogen. They can be rewarmed for 1 min each in 45C and 20C water and the viability tested on isolated leaf discs.


Cryopreservation/methods , Desiccation/methods , Spores, Fungal/growth & development
11.
Opt Express ; 25(12): A491-A501, 2017 Jun 12.
Article En | MEDLINE | ID: mdl-28788880

An Nd:YAG laser-based sodium temperature/wind lidar was developed for the measurement of the northern polar mesosphere and lower thermosphere at Tromsø (69.6N, 19.2E), Norway. Coherent light at 589 nm is produced by sum frequency generation of 1064 nm and 1319 nm from two diode laser end-pumped pulsed Nd:YAG lasers. The output power is as high as 4W, with 4 mJ/pulse at 1000 Hz repetition rate. Five tilting Cassegrain telescopes enable us to make five-direction (zenith, north, south, east, west) observation for temperature and wind simultaneously. This highly stable laser system is first of its kind to operate virtually maintenance-free during the observation season (from late September to March) since 2010.

12.
J Periodontal Res ; 52(5): 842-852, 2017 Oct.
Article En | MEDLINE | ID: mdl-28393366

BACKGROUND AND OBJECTIVE: During orthodontic tooth movement (OTM), periodontal ligament (PDL) is remodeled dynamically, which requires sufficient blood supply for the regeneration of PDL. However, little is known about the remodeling of blood vessels during OTM. In this study, we hypothesized that the orthodontic tensile strain upregulates matrix metalloproteinase-12 (MMP-12) expression in the tension zone and induces angiogenesis via degradation of type IV collagen (Col-IV) in vascular endothelial basement membrane during the early stage of OTM. MATERIAL AND METHODS: Temporal and spatial MMP-12 expression in the tension zone of PDL, during the early stage of OTM, were examined by immunohistochemistry in rats. Continuous tensile strain was applied to cultured human immortalized PDL cell lines (HPL cells) and MMP-12 expression was examined in vitro. Colocalization of MMP-12 and Col-IV in vivo were examined by immunohistochemistry. To investigate whether MMP-12 produced by HPL cells could degrade Col-IV, recombinant Col-IV was incubated in the culture supernatants of HPL cells. Intact Col-IV in vitro was also examined by western blot analysis. Finally, the changes in blood vessels in the PDL were examined by micro-computed tomography analysis with perfused contrast agents and by conventional histological analysis. RESULTS: Orthodontic tensile strain induced MMP-12 expression in PDL cells in vivo and in vitro. Immunohistochemistry revealed that MMP-12-positive cells were observed adjacent to the Col-IV-positive tubular area in the tension zone of PDL. MMP-12 in culture supernatant of HPL cells degraded recombinant Col-IV, and specific MMP-12 inhibitor blocked the Col-IV degradation. Micro-computed tomography analysis and conventional histological analysis demonstrated that the areas of blood vessels were increased in the tension zone of the PDL after OTM. CONCLUSION: We discovered that the orthodontic tensile strain upregulates MMP-12 expression in the tension zone of PDL and induces angiogenesis via degradation of Col-IV in the vascular endothelial basement membrane.


Angiogenesis Inducing Agents/adverse effects , Collagen Type IV/metabolism , Matrix Metalloproteinase 12/metabolism , Tensile Strength , Tooth Movement Techniques/adverse effects , Animals , Blood Vessels/diagnostic imaging , Blood Vessels/pathology , Cell Line , Endothelial Cells , Gene Expression Regulation , Humans , Immunohistochemistry , Male , Matrix Metalloproteinase 12/genetics , Models, Animal , Periodontal Ligament/diagnostic imaging , Periodontal Ligament/metabolism , Periodontal Ligament/pathology , Rats , Rats, Wistar , Stress, Mechanical , Time Factors , Tooth Root/diagnostic imaging , Tooth Root/pathology , Up-Regulation , X-Ray Microtomography
13.
Nat Commun ; 7: 13477, 2016 12 05.
Article En | MEDLINE | ID: mdl-27917867

In high-intensity laser light, matter can be ionized by direct multiphoton absorption even at photon energies below the ionization threshold. However on tuning the laser to the lowest resonant transition, the system becomes multiply excited, and more efficient, indirect ionization pathways become operative. These mechanisms are known as interatomic Coulombic decay (ICD), where one of the species de-excites to its ground state, transferring its energy to ionize another excited species. Here we show that on tuning to a higher resonant transition, a previously unknown type of interatomic Coulombic decay, intra-Rydberg ICD occurs. In it, de-excitation of an atom to a close-lying Rydberg state leads to electron emission from another neighbouring Rydberg atom. Moreover, systems multiply excited to higher Rydberg states will decay by a cascade of such processes, producing even more ions. The intra-Rydberg ICD and cascades are expected to be ubiquitous in weakly-bound systems exposed to high-intensity resonant radiation.

14.
Faraday Discuss ; 194: 537-562, 2016 12 16.
Article En | MEDLINE | ID: mdl-27797386

We studied the electronic and nuclear dynamics of I-containing organic molecules induced by intense hard X-ray pulses at the XFEL facility SACLA in Japan. The interaction with the intense XFEL pulse causes absorption of multiple X-ray photons by the iodine atom, which results in the creation of many electronic vacancies (positive charges) via the sequential electronic relaxation in the iodine, followed by intramolecular charge redistribution. In a previous study we investigated the subsequent fragmentation by Coulomb explosion of the simplest I-substituted hydrocarbon, iodomethane (CH3I). We carried out three-dimensional momentum correlation measurements of the atomic ions created via Coulomb explosion of the molecule and found that a classical Coulomb explosion model including charge evolution (CCE-CE model), which accounts for the concerted dynamics of nuclear motion and charge creation/charge redistribution, reproduces well the observed momentum correlation maps of fragment ions emitted after XFEL irradiation. Then we extended the study to 5-iodouracil (C4H3IN2O2, 5-IU), which is a more complex molecule of biological relevance, and confirmed that, in both CH3I and 5-IU, the charge build-up takes about 10 fs, while the charge is redistributed among atoms within only a few fs. We also adopted a self-consistent charge density-functional based tight-binding (SCC-DFTB) method to treat the fragmentations of highly charged 5-IU ions created by XFEL pulses. Our SCC-DFTB modeling reproduces well the experimental and CCE-CE results. We have also investigated the influence of the nuclear dynamics on the charge redistribution (charge transfer) using nonadiabatic quantum-mechanical molecular dynamics (NAQMD) simulation. The time scale of the charge transfer from the iodine atomic site to the uracil ring induced by nuclear motion turned out to be only ∼5 fs, indicating that, besides the molecular Auger decay in which molecular orbitals delocalized over the iodine site and the uracil ring are involved, the nuclear dynamics also play a role for ultrafast charge redistribution. The present study illustrates that the CCE-CE model as well as the SCC-DFTB method can be used for reconstructing the positions of atoms in motion, in combination with the momentum correlation measurement of the atomic ions created via XFEL-induced Coulomb explosion of molecules.

15.
Sci Rep ; 5: 10977, 2015 Jun 16.
Article En | MEDLINE | ID: mdl-26077863

Using electron spectroscopy, we have investigated nanoplasma formation from noble gas clusters exposed to high-intensity hard-x-ray pulses at ~5 keV. Our experiment was carried out at the SPring-8 Angstrom Compact free electron LAser (SACLA) facility in Japan. Dedicated theoretical simulations were performed with the molecular dynamics tool XMDYN. We found that in this unprecedented wavelength regime nanoplasma formation is a highly indirect process. In the argon clusters investigated, nanoplasma is mainly formed through secondary electron cascading initiated by slow Auger electrons. Energy is distributed within the sample entirely through Auger processes and secondary electron cascading following photoabsorption, as in the hard x-ray regime there is no direct energy transfer from the field to the plasma. This plasma formation mechanism is specific to the hard-x-ray regime and may, thus, also be important for XFEL-based molecular imaging studies. In xenon clusters, photo- and Auger electrons contribute more significantly to the nanoplasma formation. Good agreement between experiment and simulations validates our modelling approach. This has wide-ranging implications for our ability to quantitatively predict the behavior of complex molecular systems irradiated by high-intensity hard x-rays.

16.
Physiol Res ; 64(5): 711-9, 2015.
Article En | MEDLINE | ID: mdl-25804101

Recent studies have demonstrated that some microRNAs (miRNAs) inhibit bone formation by inhibiting the translation of specific genes. Several in vitro studies have suggested that miR-23a inhibits osteogenic differentiation by suppressing the translation of Runx2, a transcription factor essential for osteoblastogenesis, and of Satb2, a member of the special AT-rich binding protein family. In the present study, we used a gain-of-function approach to determine the roles of miR-23a in bone formation and homeostasis in vivo. The miR-23a transgenic (Tg) mice grew normally and their body size and weight were similar to those of wild-type (WT) littermates. Bone structure and morphology were similar in Tg and WT mice. Furthermore, the numbers of osteoblasts and osteoclasts, as well as their activities in bone were similar between Tg and WT mice. Our results indicate that miR-23 has limited roles in bone formation and maintenance in vivo in mice.


Homeostasis/physiology , MicroRNAs/biosynthesis , Osteoblasts/metabolism , Osteogenesis/physiology , Animals , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic
17.
Transplant Proc ; 47(1): 223-5, 2015.
Article En | MEDLINE | ID: mdl-25645808

Face transplants have been clinically established, and early acute rejections have been reported. Late acute rejections have been less common. Immediate and accurate diagnosis along with successful treatment is critical to prevent graft damage. This case report describes the successful treatment of a severe, steroid-resistant rejection 2 years after a full face transplant.


Antilymphocyte Serum/therapeutic use , Burns/surgery , Facial Injuries/surgery , Facial Transplantation/adverse effects , Graft Rejection/prevention & control , Immunosuppressive Agents/therapeutic use , Adult , Graft Rejection/etiology , Graft Rejection/pathology , Humans , Male
18.
Vox Sang ; 108(1): 11-7, 2015 Jan.
Article En | MEDLINE | ID: mdl-25169580

BACKGROUND AND OBJECTIVES: Donor plasmapheresis involves the removal of a weight-adjusted volume of plasma and the return of cellular components to the donor. Although plasma volume generally returns to normal, some residual effect on vital signs may be possible. This analysis was performed to determine the possible effects of plasmapheresis on blood pressure. MATERIALS AND METHODS: A 16-week study was conducted to evaluate the effects of plasma donations on cholesterol levels in healthy donors. From this study, the vital signs obtained prior to donation were analysed using statistical and dynamic analytical predictive models. RESULTS: Preliminary analyses revealed a change in systolic and diastolic blood pressure from the corresponding baseline values (Pearson Coefficient -0.44 and -0.47, respectively). Statistical models predicted a marked decrease in systolic and diastolic blood pressure following multiple donations in donors with baseline pressure in the Stage 2 hypertension range with less pronounced decreases predicted in Stage 1 donors. Little or no change in blood pressure was predicted in donors with baseline normal blood pressure or prehypertension. Dynamic models including time between donations supported these results and predicted a recovery period of about 14 days without donation in donors with Stage 2 baseline levels. CONCLUSIONS: Results suggest that systolic and diastolic blood pressure may be decreased following plasmapheresis used for plasma donations at intervals of <14 days in donors with high baseline blood pressure levels.


Blood Donors , Blood Pressure , Plasmapheresis/adverse effects , Adult , Humans , Middle Aged , Models, Cardiovascular
19.
Free Radic Res ; 49(3): 269-78, 2015 Mar.
Article En | MEDLINE | ID: mdl-25511472

Overexpression of cyclooxygenase 2 (COX-2) by stromal fibroblasts plays a critical role in the early stage of carcinogenesis. COX-2 expression is thought to be positively or negatively regulated by inflammatory chemical mediators or tumor suppressors. In this study, the contributions of inducible nitric oxide synthase (iNOS) and p53 to COX-2 expression were examined using mouse embryonic fibroblasts (MEFs) from wild-type, p53-deficient, iNOS-deficient, and p53/iNOS-deficient mice. These MEFs were treated with 1 µg/mL of lipopolysaccharide and 100 IU/mL of interferon gamma for up to 72 h. iNOS and COX-2 expression were analyzed by Western blotting. iNOS was induced earlier (16 h) in p53-deficient MEFs than in wild-type MEFs (48 h). Elevated expression of COX-2 was sustained for a longer duration in the p53-deficient MEFs. In contrast, COX-2 expression was reduced earlier in the iNOS-deficient MEFs. Addition of an exogenous NO donor (0.8 mM of S-nitroso-l-glutathione) to the iNOS-deficient MEFs augmented COX-2 expression. Co-culture with stimulated p53-deficient MEFs promoted cell proliferation of mouse rectal polyploid carcinoma CMT93 cells, but treatment with a COX-2-specific inhibitor counteracted this effect. These results suggest that loss of function of the p53 gene in stromal fibroblasts enhances COX-2 expression by enhancing iNOS expression and the resultant production of NO, contributing to the promotion of tumor growth.


Cell Proliferation , Cyclooxygenase 2/metabolism , Fibroblasts/metabolism , Neoplasms, Experimental/metabolism , Nitric Oxide/metabolism , Tumor Suppressor Protein p53/genetics , Animals , Cell Proliferation/genetics , Gene Deletion , Mice , Mice, Knockout , Neoplasms, Experimental/genetics , Nitric Oxide Synthase Type II/genetics , Signal Transduction , Stromal Cells/metabolism
...