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1.
Artigo em Inglês | MEDLINE | ID: mdl-38031151

RESUMO

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.

3.
Opt Express ; 25(12): A491-A501, 2017 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-28788880

RESUMO

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.

4.
J Periodontal Res ; 52(5): 842-852, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28393366

RESUMO

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.


Assuntos
Indutores da Angiogênese/efeitos adversos , Colágeno Tipo IV/metabolismo , Metaloproteinase 12 da Matriz/metabolismo , Resistência à Tração , Técnicas de Movimentação Dentária/efeitos adversos , Animais , Vasos Sanguíneos/diagnóstico por imagem , Vasos Sanguíneos/patologia , Linhagem Celular , Células Endoteliais , Regulação da Expressão Gênica , Humanos , Imuno-Histoquímica , Masculino , Metaloproteinase 12 da Matriz/genética , Modelos Animais , Ligamento Periodontal/diagnóstico por imagem , Ligamento Periodontal/metabolismo , Ligamento Periodontal/patologia , Ratos , Ratos Wistar , Estresse Mecânico , Fatores de Tempo , Raiz Dentária/diagnóstico por imagem , Raiz Dentária/patologia , Regulação para Cima , Microtomografia por Raio-X
7.
Cryo Letters ; 38(3): 250-256, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28767748

RESUMO

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.


Assuntos
Criopreservação/métodos , Dessecação/métodos , Esporos Fúngicos/crescimento & desenvolvimento
8.
Faraday Discuss ; 194: 537-562, 2016 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-27797386

RESUMO

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.

10.
Vox Sang ; 108(1): 11-7, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25169580

RESUMO

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.


Assuntos
Doadores de Sangue , Pressão Sanguínea , Plasmaferese/efeitos adversos , Adulto , Humanos , Pessoa de Meia-Idade , Modelos Cardiovasculares
12.
Phys Rev Lett ; 110(17): 173005, 2013 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-23679721

RESUMO

We have investigated multiphoton multiple ionization dynamics of xenon atoms using a new x-ray free-electron laser facility, SPring-8 Angstrom Compact free electron LAser (SACLA) in Japan, and identified that Xe(n+) with n up to 26 is produced at a photon energy of 5.5 keV. The observed high charge states (n≥24) are produced via five-photon absorption, evidencing the occurrence of multiphoton absorption involving deep inner shells. A newly developed theoretical model, which shows good agreement with the experiment, elucidates the complex pathways of sequential electronic decay cascades accessible in heavy atoms. The present study of heavy-atom ionization dynamics in high-intensity hard-x-ray pulses makes a step forward towards molecular structure determination with x-ray free-electron lasers.

13.
Phys Rev Lett ; 110(5): 053003, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23414017

RESUMO

Ionization and fragmentation of methylselenol (CH(3)SeH) molecules by intense (>10(17) W/cm(2)) 5 fs x-ray pulses (hω=2 keV) are studied by coincident ion momentum spectroscopy. We contrast the measured charge state distribution with data on atomic Kr, determine kinetic energies of resulting ionic fragments, and compare them to the outcome of a Coulomb explosion model. We find signatures of ultrafast charge redistribution from the inner-shell ionized Se atom to its molecular partners, and observe significant displacement of the atomic constituents in the course of multiple ionization.

14.
Phys Rev Lett ; 111(7): 073002, 2013 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-23992061

RESUMO

When exposed to ultraintense x-radiation sources such as free electron lasers (FELs) the innermost electronic shell can efficiently be emptied, creating a transient hollow atom or molecule. Understanding the femtosecond dynamics of such systems is fundamental to achieving atomic resolution in flash diffraction imaging of noncrystallized complex biological samples. We demonstrate the capacity of a correlation method called "partial covariance mapping" to probe the electron dynamics of neon atoms exposed to intense 8 fs pulses of 1062 eV photons. A complete picture of ionization processes competing in hollow atom formation and decay is visualized with unprecedented ease and the map reveals hitherto unobserved nonlinear sequences of photoionization and Auger events. The technique is particularly well suited to the high counting rate inherent in FEL experiments.

15.
Vox Sang ; 105(2): 108-15, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23517282

RESUMO

BACKGROUND AND OBJECTIVES: LDL apheresis is used to treat patients with familial hypercholesterolaemia, and low-volume plasmapheresis for plasma donation may similarly lower cholesterol levels in some donors. This study was designed to assess the effect of plasmapheresis on total, LDL and HDL cholesterol levels in a plasma donor population. MATERIALS AND METHODS: This was a prospective, unblinded longitudinal cohort study in which a blood sample was obtained for analysis before each donation. Data from 663 donors were analysed using a multivariable repeated measures regression model with a general estimating equations approach with changes in cholesterol as the primary outcome measure. RESULTS: The model predicted a significant decrease in total and LDL cholesterol for both genders and all baseline cholesterol levels (P < 0.01). The greatest total cholesterol decreases (women, -46.8 mg/dL; men, -32.2 mg/dL) were associated with high baseline levels and 2-4 days between donations. Small but statistically significant increases (P ≤ 0.01) in HDL cholesterol were predicted for donors with low baseline levels. CONCLUSIONS: These results suggest that, in donors with elevated baseline cholesterol levels, total and LDL cholesterol levels may decrease during routine voluntary plasmapheresis.


Assuntos
Doadores de Sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Modelos Biológicos , Plasmaferese , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
16.
Sci Rep ; 13(1): 6142, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-37061592

RESUMO

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.

17.
Sci Rep ; 13(1): 10292, 2023 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-37357245

RESUMO

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.

18.
Phys Rev Lett ; 108(15): 153003, 2012 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-22587249

RESUMO

We have performed x-ray two-photon photoelectron spectroscopy using the Linac Coherent Light Source x-ray free-electron laser in order to study double core-hole (DCH) states of CO2, N2O, and N2. The experiment verifies the theory behind the chemical sensitivity of two-site DCH states by comparing a set of small molecules with respect to the energy shift of the two-site DCH state and by extracting the relevant parameters from this shift.

19.
Phys Rev Lett ; 108(6): 063007, 2012 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-22401068

RESUMO

Two-color (x-ray+infrared) electron spectroscopy is used for investigating laser-assisted KLL Auger decay following 1s photoionization of atomic Ne with few-femtosecond x-ray pulses from the Linac Coherent Light Source. In an angle-resolved experiment, the overall width of the laser-modified Auger-electron spectrum and its structure change significantly as a function of the emission angle. The spectra are characterized by a strong intensity variation of the sidebands revealing a gross structure. This variation is caused, as predicted by theory, by the interference of electrons emitted at different times within the duration of one optical cycle of the infrared dressing laser, which almost coincides with the lifetime of the Ne 1s vacancy.

20.
Orthod Craniofac Res ; 15(2): 84-91, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22515184

RESUMO

OBJECTIVES: The BALB/c-bm/bm mouse is characterized by short limbs and short tail attributed to undersulfated glycosaminoglycans. Anterior transverse crossbite sometimes spontaneously appears in BALB/c-bm/bm mice. The BALB/c-bm/bm mouse shows a short nose and cranium. The reason for hypo-growth of anterior craniofacial structures has not been clarified, although the nasal septal cartilage might be related to the growth of anterior craniofacial structures. Therefore, the purpose of this study was to evaluate histological findings of the nasal septal cartilage at the border region of the ethmoid and sphenoid bone in BALB/c-bm/bm mice. MATERIALS AND METHODS: BALB/c mice (wild type) and BALB/c-bm/bm mice with normal occlusion (bm/bm) were used. Sagittal sections of female mice aged 2, 4, and 8 weeks were stained with hematoxylin and eosin for histological analysis. RESULTS: At the border region between the nasal septal cartilage and the ethmoid bone in bm/bm, the area of proliferative zone was significantly smaller than that in wild type. At the border regions between the nasal septal cartilage and both the ethmoid and sphenoid bones, the number of proliferative chondrocytes was significantly smaller. Normal endochondral ossification was not observed at the border region between the nasal septal cartilage and the sphenoid bone in bm/bm. CONCLUSION: The findings suggest that disorder of endochondral ossification in the nasal septal cartilage contributes to the hypo-growth of anterior craniofacial structures in bm/bm.


Assuntos
Condrócitos/patologia , Má Oclusão/genética , Cartilagens Nasais/patologia , Septo Nasal/patologia , Osteogênese/genética , Animais , Proliferação de Células , Nanismo/enzimologia , Nanismo/genética , Osso Etmoide/patologia , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Mutantes , Osso Esfenoide/patologia
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