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1.
Sci Rep ; 13(1): 18128, 2023 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-37875562

RESUMO

The aims of this study were to determine the prevalence and predictors of nocturnal polyuria (NP) in Japanese patients. This multicentral, observational study enrolled patients with the chief complaint of nocturia at 17 Japanese institutions between January 2018 and December 2022. The frequency of daily voiding and volume of urination were evaluated using bladder diaries. NP was diagnosed in patients with an NP index of > 33%. The primary endpoint was NP prevalence in patients with nocturia. The secondary endpoints were the prevalence of NP according to sex and age and the identification of factors predicting NP. This study analyzed 875 eligible patients. NP was present in 590 (67.4%) patients, with prevalence rates of 66.6% and 70.0% in men and women, respectively. Age ≥ 78 years, body mass index (BMI) < 23.0 kg/m2, and patients with ischemic heart or cerebrovascular disease were significant predictors of NP (P < 0.001, P < 0.001, P = 0.014, P = 0.016, respectively). This is the first large multicenter study to investigate the prevalence of NP in Japanese patients with nocturia. NP has a prevalence of 67.4%. Significant predictors of NP include age, BMI, and cardiovascular disease.


Assuntos
Noctúria , Masculino , Humanos , Feminino , Idoso , Noctúria/epidemiologia , Noctúria/diagnóstico , Poliúria/complicações , Poliúria/epidemiologia , Poliúria/diagnóstico , Estudos Retrospectivos , Prevalência , População do Leste Asiático
2.
J Gen Appl Microbiol ; 69(2): 125-130, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37302826

RESUMO

Thermus thermophilus is reportedly polyploid and carries four to five identical genome copies per cell, based on molecular biological experiments. To directly detect polyploidy in this bacterium, we performed live cell imaging by X-ray free-electron laser (XFEL) diffraction and observed its internal structures. The use of femtosecond XFEL pulses enables snapshots of live, undamaged cells. For successful XFEL imaging, we developed a bacterial culture method using a starch- and casein-rich medium that produces a predominance of rod-shaped cells shorter than the focused XFEL beam size, which is slightly smaller than 2 µm. When cultured in the developed medium, the length of T. thermophilus cells, which is typically ~4 µm, was less than half its usual length. We placed living cells in a micro-liquid enclosure array and successively exposed each enclosure to a single XFEL pulse. A cell image was successfully obtained by the coherent diffractive imaging technique with iterative phase retrieval calculations. The reconstructed cell image revealed five peaks, which are most likely to be nucleoids, arranged in a row in the polyploid cell without gaps. This study demonstrates that XFELs offer a novel approach for visualizing the internal nanostructures of living, micrometer-sized, polyploid bacterial cells.


Assuntos
Lasers , Thermus thermophilus , Humanos , Thermus thermophilus/genética , Raios X , Difração de Raios X , Poliploidia
3.
Nat Commun ; 13(1): 5300, 2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36100607

RESUMO

With the emergence of X-ray free-electron lasers (XFELs), coherent diffractive imaging (CDI) has acquired a capability for single-particle imaging (SPI) of non-crystalline objects under non-cryogenic conditions. However, the single-shot spatial resolution is limited to ~5 nanometres primarily because of insufficient fluence. Here, we present a CDI technique whereby high resolution is achieved with very-high-fluence X-ray focusing using multilayer mirrors with nanometre precision. The optics can focus 4-keV XFEL down to 60 nm × 110 nm and realize a fluence of >3 × 105 J cm-2 pulse-1 or >4 × 1012 photons µm-2 pulse-1 with a tenfold increase in the total gain compared to conventional optics due to the high demagnification. Further, the imaging of fixed-target metallic nanoparticles in solution attained an unprecedented 2-nm resolution in single-XFEL-pulse exposure. These findings can further expand the capabilities of SPI to explore the relationships between dynamic structures and functions of native biomolecular complexes.

4.
Nano Lett ; 22(11): 4603-4607, 2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35612588

RESUMO

Experimental characterization of the nanostructure of metastable functional materials has attracted significant attention with recent advances in computational materials discovery. However, since metastable glass-ceramics are easily damaged by irradiation, damage-free nanoimaging has not been realized thus far. Herein, we propose novel high-contrast coherent diffractive imaging that quantitatively analyzes the intact internal nanostructure of metastable glass-ceramics using femtosecond X-ray pulses. The immersion of sample particles in a solvent helps enhance the reconstructed image contrast and allows us to distinguish an ∼7% electron density difference between an amorphous form and crystals. Furthermore, morphological operations with a band-pass filter quantitatively elucidate the depth information. The evaluated volume ratio of the amorphous to crystalline phases is ∼2.5:1 for the measured metastable (Li2S)70-(P2S5)30 glass-ceramic particle. Sulfide glass-ceramics are used as electrolytes for all-solid-state batteries, which are indispensable for reducing the carbon footprint. Our results will facilitate structural studies on fragile metastable materials with important scientific and industrial implications.

5.
Rev Sci Instrum ; 91(8): 083706, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32872956

RESUMO

We developed micro-liquid enclosure arrays (MLEAs) for holding solution samples in coherent diffractive imaging (CDI) using x-ray free-electron lasers (XFELs). Hundreds of fully isolated micro-liquid enclosures are arranged in a single MLEA chip for efficient measurement, where each enclosure is destroyed after exposure to a single XFEL pulse. A semi-automated MLEA assembling system was also developed to enclose solution samples into MLEAs efficiently at high precision. We performed XFEL-based CDI experiments using MLEAs and imaged in-solution structures of self-assembled gold nanoparticles. The sample hit rate can be optimized by adjusting solution concentration, and we achieved a single-particle hit rate of 31%, which is not far from the theoretical upper limit of 37% derived from the Poisson statistics. MELAs allow us to perform CDI measurement under controlled solution conditions and will help reveal the nanostructures and dynamics of particles in solution.

6.
Phys Chem Chem Phys ; 22(5): 2622-2628, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-31441927

RESUMO

X-ray free-electron lasers (XFELs) opened up a possibility for molecular-scale single particle imaging (SPI) without the need for crystallization. In SPI experiments, the orientation of each particle has to be determined from the measured diffraction pattern. Preparing unidirectionally-aligned particles can facilitate the determination of the sample orientation. Here, we show the design principles of a liquid cell for three-dimensional imaging of unidirectionally-aligned particles in solution with XFELs. The liquid cell was designed so that neither incident X-rays nor diffracted X-rays are blocked by the substrate of the liquid cell even at high tilt angles. As a feasibility evaluation, we performed coherent diffraction measurements using the cells with a 1 µm focused XFEL beam. We successfully measured coherent diffraction patterns of a nano-fabricated metal pattern at 70° tilt angle and obtained the reconstructed image by applying iterative phase retrieval. The liquid cell will be usefully applied to molecular-scale SPI by using more tightly focused XFELs. In particular, imaging of membrane proteins embedded in lipid membranes is expected to have an enormous impact on life science and medicine.


Assuntos
Imageamento Tridimensional/métodos , Lasers , Elétrons , Desenho de Equipamento , Ouro/química , Imageamento Tridimensional/instrumentação
7.
Int Urogynecol J ; 30(11): 1933-1938, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30643979

RESUMO

INTRODUCTION AND HYPOTHESIS: The steep Trendelenburg position, high pneumoperitoneum pressure, and longer surgical time may lead to significantly increased intraocular pressure (IOP), which could result in unexpected eye disease complications, including perioperative visual loss (POVL). We monitored IOP to induce early laparoscopic sacral colpopexy (LSC) safely. METHODS: This prospective study enrolled 39 patients with pelvic organ prolapse (POP), including 10 with eye diseases (6 with normal tension glaucoma and 4 with a narrow anterior chamber and normal range IOP). Enrolled patients underwent LSC under the same surgical settings involving a pneumoperitoneum of 10 mmHg and a Trendelenburg position of 15°. We measured IOP at seven time points during surgery and estimated IOP changes with time in patients with or without eye diseases. RESULTS: All patients, with or without eye diseases, experienced significantly elevated IOP during LSC. There were no significant differences between these groups. The average maximal IOP reached 20 mmHg at the end of surgery, and recovered to baseline values with the patient in the supine position at the end of anesthesia. No patient had an IOP of >40 mmHg as a critical threshold during surgery, and no substantial clinical eye symptoms were seen after LSC. CONCLUSIONS: Laparoscopic sacral colpopexy using an pneumoperitoneum of 10 mmHg and a Trendelenburg position of 15° during a 3-h surgical period could be performed within a safe range of IOP.


Assuntos
Pressão Intraocular/fisiologia , Laparoscopia , Glaucoma de Baixa Tensão/fisiopatologia , Monitorização Intraoperatória , Prolapso de Órgão Pélvico/fisiopatologia , Prolapso de Órgão Pélvico/cirurgia , Vagina/cirurgia , Idoso , Feminino , Procedimentos Cirúrgicos em Ginecologia/métodos , Humanos , Glaucoma de Baixa Tensão/complicações , Pessoa de Meia-Idade , Prolapso de Órgão Pélvico/complicações , Estudos Prospectivos , Sacro
8.
Sci Adv ; 4(2): eaao3547, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29492456

RESUMO

A valence critical end point existing near the absolute zero provides a unique case for the study of a quantum version of the strong density fluctuation at the Widom line in the supercritical fluids. Although singular charge and orbital dynamics are suggested theoretically to alter the electronic structure significantly, breaking down the standard quasi-particle picture, this has never been confirmed experimentally to date. We provide the first empirical evidence that the proximity to quantum valence criticality leads to a clear breakdown of Fermi liquid behavior. Our detailed study of the mixed valence compound α-YbAlB4 reveals that a small chemical substitution induces a sharp valence crossover, accompanied by a pronounced non-Fermi liquid behavior characterized by a divergent effective mass and unusual T/B scaling in the magnetization.

9.
Hinyokika Kiyo ; 63(3): 101-105, 2017 Mar.
Artigo em Japonês | MEDLINE | ID: mdl-28331166

RESUMO

To examine the efficacy and safety of tadalafil in the treatment of lower urinary tract symptoms suggestive of benign prostatic hyperplasia with chronic pelvic pain syndrome, we treated 23 Japanese men with tadalafil 5 mg once daily for 4 weeks. The mean age of the participantswas58.7 yearsand the prostate volume was25. 2 ml. Significant improvementsin total International Prostatic Symptom Score, International Prostatic Symptom Score Quality of Life Index, total National Institutes of Health Chronic Prostatitis Symptom Index score, pain subscore, urinary symptom subscore, and quality of life impact subscore, were observed for tadalafil versus before treatment. These findings confirm that tadalafil is a valuable new treatment option for patients with benign prostatic hyperplasia complicated by chronic pelvic pain syndrome.


Assuntos
Dor Pélvica/etiologia , Inibidores da Fosfodiesterase 5/uso terapêutico , Hiperplasia Prostática/tratamento farmacológico , Tadalafila/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Hiperplasia Prostática/complicações , Resultado do Tratamento
10.
J Synchrotron Radiat ; 24(Pt 1): 142-149, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-28009553

RESUMO

X-ray science has greatly benefited from the progress in X-ray optics. Advances in the design and the manufacturing techniques of X-ray optics are key to the success of various microscopic and spectroscopic techniques practiced today. Here the generation of apodized X-ray illumination using a two-stage deformable Kirkpatrick-Baez mirror system is presented. Such apodized illumination is marked by the suppression of the side-lobe intensities of the focused beam. Thus generated apodized illumination was employed to improve the image quality in scanning X-ray fluorescence microscopy. Imaging of a non-isolated object by coherent X-ray diffractive imaging with apodized illumination in a non-scanning mode is also presented.

11.
Sci Rep ; 6: 24801, 2016 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-27097853

RESUMO

Unlike the electrostatic and electromagnetic lenses used in electron microscopy, most X-ray focusing optical systems have fixed optical parameters with constant numerical apertures (NAs). This lack of adaptability has significantly limited application targets. In the research described herein, we developed a variable-NA X-ray focusing system based on four deformable mirrors, two sets of Kirkpatrick-Baez-type focusing mirrors, in order to control the focusing size while keeping the position of the focus unchanged. We applied a mirror deformation procedure using optical/X-ray metrology for offline/online adjustments. We performed a focusing test at a SPring-8 beamline and confirmed that the beam size varied from 108 nm to 560 nm (165 nm to 1434 nm) in the horizontal (vertical) direction by controlling the NA while maintaining diffraction-limited conditions.

12.
J Am Chem Soc ; 138(10): 3274-7, 2016 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-26924649

RESUMO

We demonstrate that binary mixtures of small and large gold nanoparticles (GNPs) (5/15, 5/30, 10/30, and 15/30 nm in diameter) in the presence of a glucose-terminated fluorinated oligo(ethylene glycol) ligand can spontaneously form size-segregated assemblies. The outermost layer of the assembly is composed of a single layer of small-sized GNPs, while the larger-sized GNPs are located in the interior, forming what is referred to as a yolk/shell assembly. Time course study reveals that small and large GNPs aggregate together, and these kinetically trapped aggregations were transformed into a size-segregated structure by repeating fusions. A yolk/shell structure was directly visualized in solution by X-ray laser diffraction imaging, indicating that the structure was truly formed in solution, but not through a drying process.

13.
Opt Express ; 23(22): 28182-90, 2015 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-26561089

RESUMO

Coherent diffraction imaging (CDI) is an established lensless imaging method widely used at the x-ray regime applicable to the imaging of non-periodic materials. Conventional CDI can practically image isolated objects only, which hinders the broader application of the method. We present the imaging of non-isolated objects by employing recently proposed "non-scanning" apodized-illumination CDI at an optical wavelength. We realized isolated apodized illumination with a specially designed optical configuration and succeeded in imaging phase objects as well as amplitude objects. The non-scanning nature of the method is important particularly in imaging live cells and tissues, where fast imaging is required for non-isolated objects, and is an advantage over ptychography. We believe that our result of phase contrast imaging at an optical wavelength can be extended to the quantitative phase imaging of cells and tissues. The method also provides the feasibility of the lensless single-shot imaging of extended objects with x-ray free-electron lasers.

14.
Langmuir ; 31(14): 4054-62, 2015 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-25796963

RESUMO

This study aims at the synthesis of Janus gold nanoparticles (Janus GNPs) with hydrophilic/hydrophobic faces by a simple ligand exchange reaction in an homogeneous system and at the elucidation of the self-assembled structures of the Janus GNPs in water. As hydrophilic surface ligands, we synthesized hexaethylene glycol (E6)-terminated thiolate ligands with C3, C7, or C11 alkyl chains, referred to as E6C3, E6C7, and E6C11, respectively. As a hydrophobic ligand, a butyl-headed thiolate ligand C4-E6C11, in which a C4 alkyl was introduced on the E6C11 terminus, was synthesized. The degree of segregation between the two ligands on the GNPs (5 nm in diameter) was examined by matrix-assisted laser desorption/ionization time-of fright mass spectrometry (MALDI-TOF MS) analysis. We found that the choice of immobilization methods, one-step or two-step addition of the two ligands to the GNP solution, crucially affects the degree of segregation. The two-step addition of a hydrophilic ligand (E6C3) followed by a hydrophobic ligand (C4-E6C11) produced a large degree of segregation on the GNPs, providing Janus-like GNPs. When dispersed in water, these Janus-like GNPs formed assemblies of ∼160 nm in diameter, whereas Domain GNPs, in which the two ligands formed partial domains on the surface, were precipitated even when the molar ratio of the hydrophilic ligand and the hydrophobic ligand on the surface of the NPs was almost 1:1. The assembled structure of the Janus-like GNPs in water was directly observed by pulsed coherent X-ray solution scattering using an X-ray free-electron laser, revealing irregular spherical structures with uneven surfaces.


Assuntos
Ouro/química , Interações Hidrofóbicas e Hidrofílicas , Nanopartículas Metálicas/química , Nanotecnologia , Água/química , Ligantes , Propriedades de Superfície
15.
Nano Lett ; 14(5): 2413-8, 2014 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-24742218

RESUMO

The continuing effort to utilize the unique properties present in a number of strongly correlated transition metal oxides for novel device applications has led to intense study of their transitional phase state behavior. Here we report on time-resolved coherent X-ray diffraction measurements on a single vanadium dioxide nanocrystal undergoing a solid-solid phase transition, using the SACLA X-ray Free Electron Laser (XFEL) facility. We observe an ultrafast transition from monoclinic to tetragonal crystal structure in a single vanadium dioxide nanocrystal. Our findings demonstrate that the structural change occurs in a number of distinct stages attributed to differing expansion modes of vanadium atom pairs.

16.
Nat Commun ; 5: 3052, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24394916

RESUMO

Emerging X-ray free-electron lasers with femtosecond pulse duration enable single-shot snapshot imaging almost free from sample damage by outrunning major radiation damage processes. In bioimaging, it is essential to keep the sample close to its natural state. Conventional high-resolution imaging, however, suffers from severe radiation damage that hinders live cell imaging. Here we present a method for capturing snapshots of live cells kept in a micro-liquid enclosure array by X-ray laser diffraction. We place living Microbacterium lacticum cells in an enclosure array and successively expose each enclosure to a single X-ray laser pulse from the SPring-8 Angstrom Compact Free-Electron Laser. The enclosure itself works as a guard slit and allows us to record a coherent diffraction pattern from a weakly-scattering submicrometre-sized cell with a clear fringe extending up to a 28-nm full-period resolution. The reconstructed image reveals living whole-cell structures without any staining, which helps advance understanding of intracellular phenomena.


Assuntos
Actinobacteria/citologia , Imageamento Tridimensional/métodos , Difração de Raios X/métodos , Animais , Lasers , Espalhamento de Radiação
17.
Opt Express ; 21(8): 9267-76, 2013 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-23609637

RESUMO

We propose a coherent x-ray zoom condenser lens composed of two-stage deformable Kirkpatrick-Baez mirrors. The lens delivers coherent x-rays with a controllable beam size, from one micrometer to a few tens of nanometers, at a fixed focal position. The lens is suitable for diffractive and scanning microscopy. We also propose non-scanning coherent diffraction microscopy for extended objects by using an apodized focused beam produced by the lens with a spatial filter. The proposed apodized-illumination method will be useful in highly efficient imaging with ultimate storage ring sources, and will also open the way to single-shot coherent diffraction microscopy of extended objects with x-ray free-electron lasers.


Assuntos
Aumento da Imagem/instrumentação , Lentes , Difração de Raios X/instrumentação , Microtomografia por Raio-X/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento
18.
Curr Opin Struct Biol ; 22(5): 670-8, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22954648

RESUMO

Small-angle X-ray scattering (SAXS) of macromolecular systems in solution has become an obvious complement to high resolution structural studies. Using SAXS, structural hypotheses can be directly tested against experimental data in solution. Conformational changes or complex formation can be monitored, and help understanding structure-function relationships. Additionally, the reliability of the data has been much strengthened by on-line purification approaches. Moreover, when coherent X-rays are used for sample illumination, SAXS patterns become speckled and can provide electron-density maps directly by computational phase-retrieval methods. Furthermore, X-ray free-electron laser with femtosecond pulse duration will enable us to take time-frozen images of biomolecules in solution free from radiation damage. In this paper, recent experimental and methodological advances in both classical and coherent SAXS are reviewed.


Assuntos
Espalhamento a Baixo Ângulo , Difração de Raios X/métodos , Humanos , Substâncias Macromoleculares/química , Biologia Molecular/métodos , Imagem Molecular , Soluções
19.
Nucleus ; 3(5): 404-10, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22825571

RESUMO

How is a long strand of genomic DNA packaged into a mitotic chromosome or nucleus? The nucleosome fiber (beads-on-a-string), in which DNA is wrapped around core histones, has long been assumed to be folded into a 30-nm chromatin fiber, and a further helically folded larger fiber. However, when frozen hydrated human mitotic cells were observed using cryoelectron microscopy, no higher-order structures that included 30-nm chromatin fibers were found. To investigate the bulk structure of mitotic chromosomes further, we performed small-angle X-ray scattering (SAXS), which can detect periodic structures in noncrystalline materials in solution. The results were striking: no structural feature larger than 11 nm was detected, even at a chromosome-diameter scale (~1 µm). We also found a similar scattering pattern in interphase nuclei of HeLa cells in the range up to ~275 nm. Our findings suggest a common structural feature in interphase and mitotic chromatins: compact and irregular folding of nucleosome fibers occurs without a 30-nm chromatin structure.


Assuntos
Cromatina/química , Estruturas Cromossômicas/química , Núcleo Celular/metabolismo , Cromatina/metabolismo , Estruturas Cromossômicas/metabolismo , Células HeLa , Histonas/química , Histonas/metabolismo , Humanos , Interfase , Mitose , Nucleossomos/química , Nucleossomos/metabolismo , Espalhamento a Baixo Ângulo , Difração de Raios X
20.
EMBO J ; 31(7): 1644-53, 2012 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-22343941

RESUMO

How a long strand of genomic DNA is compacted into a mitotic chromosome remains one of the basic questions in biology. The nucleosome fibre, in which DNA is wrapped around core histones, has long been assumed to be folded into a 30-nm chromatin fibre and further hierarchical regular structures to form mitotic chromosomes, although the actual existence of these regular structures is controversial. Here, we show that human mitotic HeLa chromosomes are mainly composed of irregularly folded nucleosome fibres rather than 30-nm chromatin fibres. Our comprehensive and quantitative study using cryo-electron microscopy and synchrotron X-ray scattering resolved the long-standing contradictions regarding the existence of 30-nm chromatin structures and detected no regular structure >11 nm. Our finding suggests that the mitotic chromosome consists of irregularly arranged nucleosome fibres, with a fractal nature, which permits a more dynamic and flexible genome organization than would be allowed by static regular structures.


Assuntos
Cromossomos Humanos/química , Mitose , Nucleossomos/química , Cromatina/química , Cromatina/ultraestrutura , Cromossomos Humanos/ultraestrutura , Microscopia Crioeletrônica , Células HeLa , Humanos , Nucleossomos/ultraestrutura , Dobramento de Proteína , Espalhamento a Baixo Ângulo , Difração de Raios X
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