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1.
Esophagus ; 2024 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-38431541

RESUMEN

BACKGROUND: Systemic inflammatory response is significant prognostic indicator in patients with various diseases. The relationship between prognostic scoring systems based on the modified Glasgow Prognostic Score (mGPS) and achalasia in patients treated with laparoscopic Heller­myotomy with Dor­fundoplication (LHD) remains uninvestigated. This study aimed to examine the role of mGPS in patients with achalasia. METHODS: 457 patients with achalasia who underwent LHD as the primary surgery between September 2005 and December 2020 were included. We divided patients into the mGPS 0 and mGPS 1 or 2 groups and compared the patients' background, pathophysiology, symptoms, surgical outcomes, and postoperative course. RESULTS: mGPS was 0 in 379 patients and 1 or 2 in 78 patients. Preoperative vomiting and pneumonia were more common in patients with mGPS of 1 or 2. There were no differences in surgical outcomes. Postoperative upper gastrointestinal endoscopy revealed that severe esophagitis was more frequently observed in patients with mGPS of 1 or 2 (P < 0.01). The clinical success was 91% and 99% in the mGPS 0 and mGPS 1 or 2 groups, respectively (P < 0.01). CONCLUSIONS: Although severe reflux esophagitis was more common in patients with achalasia with a high mGPS, good clinical success was obtained regardless of the preoperative mGPS.

2.
Sci Rep ; 14(1): 5374, 2024 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-38438508

RESUMEN

In Gram-positive bacteria, sophisticated machineries to acquire the heme group of hemoglobin (Hb) have evolved to extract the precious iron atom contained in it. In the human pathogen Streptococcus pyogenes, the Shr protein is a key component of this machinery. Herein we present the crystal structure of hemoglobin-interacting domain 2 (HID2) of Shr bound to Hb. HID2 interacts with both, the protein and heme portions of Hb, explaining the specificity of HID2 for the heme-bound form of Hb, but not its heme-depleted form. Further mutational analysis shows little tolerance of HID2 to interfacial mutations, suggesting that its interaction surface with Hb could be a suitable candidate to develop efficient inhibitors abrogating the binding of Shr to Hb.


Asunto(s)
Hemoproteínas , Humanos , Hemoproteínas/genética , Streptococcus pyogenes/genética , Hemo , Reconocimiento en Psicología , Hierro
3.
Exp Eye Res ; 241: 109858, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38467176

RESUMEN

The eye lens is responsible for focusing objects at various distances onto the retina and its refractive power is determined by its surface curvature as well as its internal gradient refractive index (GRIN). The lens continues to grow with age resulting in changes to the shape and to the GRIN profile. The present study aims to investigate how the ageing process may influence lens optical development. Murine lenses of accelerated senescence-prone strain (SAMP8) aged from 4 to 50 weeks; senescence-resistant strain (SAMR1) aged from 5 to 52 weeks as well as AKR strain (served as control) aged from 6 to 70 weeks were measured using the X-ray interferometer at the SPring-8 synchrotron Japan within three consecutive years from 2020 to 2022. Three dimensional distributions of the lens GRIN were reconstructed using the measured data and the lens shapes were determined using image segmentation in MatLab. Variations in the parameters describing the lens shape and the GRIN profile with age were compared amongst three mouse strains. With advancing age, both the lens anterior and posterior surface flattens and the lens sagittal thickness increase in all three mouse strains (Anterior radius of curvature increase at 0.008 mm/week, 0.007 mm/week and 0.002 mm/week while posterior radius of curvature increase at 0.002 mm/week, 0.007 mm/week and 0.003 mm/week respectively in AKR, SAMP8 and SAMR1 lenses). Compared with the AKR strain, the SAMP8 samples demonstrate a higher rate of increase in the posterior curvature radius (0.007 mm/week) and the thickness (0.015 mm/week), whilst the SAMR1 samples show slower increases in the anterior curvature radius (0.002 mm/week) and its thickness (0.013 mm/week). There are similar age-related trends in GRIN shape in the radial direction (in all three types of murine lenses nr2 and nr6 increase with age while nr4 decrease with age consistently) but not in the axial direction amongst three mouse strains (nz1 of AKR lens decrease while of SAMP8 and SAMR1 increase with age; nz2 of all three models increase with age; nz3 of AKR lens increase while of SAMP8 and SAMR1 decrease with age). The ageing process can influence the speed of lens shape change and affect the GRIN profile mainly in the axial direction, contributing to an accelerated decline rate of the optical power in the senescence-prone strain (3.5 D/week compared to 2.3 D/week in the AKR control model) but a retardatory decrease in the senescence-resistant strain (2.1 D/week compared to the 2.3D/week in the AKR control model).


Asunto(s)
Envejecimiento , Cristalino , Ratones , Animales , Japón
4.
Biol Trace Elem Res ; 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38489123

RESUMEN

For understanding trace element dynamics in tissues, methods for analyzing elemental distribution and localization without destroying tissue structures and cell arrangements are desired. Synchrotron radiation X-ray fluorescence (SR-XRF) analysis is one of the non-destructive and multi-element simultaneous analyses. The kidney is the major excretion pathway of cesium (Cs) taken into the body, and an understanding of cesium distribution in the kidney would be useful for establishing technology to facilitate the excretion of radioactive Cs from the body due to nuclear disasters. In the present study, the distribution of cesium and trace elements, such as iron (Fe) and zinc (Zn), corresponding to the kidney structure was examined in Cs-administered mice by SR-XRF imaging with high-energy excitation X-rays (40 keV). By beam scanning with a 200-µm square beam, clear Cs images corresponding to the renal layer structure were obtained for the renal specimen at the early phase after Cs administration with the mean renal Cs concentration of 24.1 ± 3.2 µg/g. Cs was distributed mainly in the medulla and the outer stripe of the outer medulla located in the center area of the kidney. Unlike the Cs distribution, endogenous Fe and Zn tended to be lower in the medulla than in the outer stripe of the outer medulla and the cortex. This method is effective for analyzing Cs distribution because it can simultaneously analyze the distribution of endogenous trace elements.

5.
Commun Biol ; 7(1): 17, 2024 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-38172227

RESUMEN

High-resolution 3D imaging of species with exoskeletons such as shell-bearing mollusks typically involves destructive steps. Nondestructive alternatives are desirable since samples can be rare and valuable, and destructive steps are time-consuming and may distort the tissue. Here, we show for the first time that propagation-based phase-contrast X-ray imaging can significantly increase contrast in mollusks with intact shells. By using the recently upgraded monochromator at the SPring-8 BL20B2 synchrotron beamline, we imaged six species of mollusks, showing that X-ray phase contrast enhances soft-tissue contrast. Features that are almost invisible in conventional attenuation-based micro-computed tomography (micro-CT) are clearly reproduced with phase-contrast imaging under the same scan conditions. Furthermore, this method can reveal features such as growth rings in the shell and differentiate between calcite and aragonite crystal forms. Phase-contrast imaging can thus serve as a compelling alternative when destructive methods are not an option.


Asunto(s)
Moluscos , Sincrotrones , Animales , Microtomografía por Rayos X/métodos , Rayos X
6.
Esophagus ; 21(1): 67-75, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37817043

RESUMEN

BACKGROUND: While laparoscopic fundoplication is a standard surgical procedure for patients with esophageal hiatal hernias, the postoperative recurrence of esophageal hiatal hernias is a problem for patients with giant hernias, elderly patients, or obese patients. Although there are some reports indicating that reinforcement with mesh is effective, there are differing opinions regarding the use thereof. The aim of this study is to investigate whether mesh reinforcement is effective for laparoscopic fundoplication in patients with esophageal hiatus hernias. METHODS: The subjects included 280 patients who underwent laparoscopic fundoplication as the initial surgery for giant esophageal hiatal hernias, elderly patients aged 75 years or older, and obese patients with a BMI of 28 or higher, who were considered at risk of recurrent hiatal hernias based on the previous reports. Of the subject patients, 91 cases without mesh and 86 cases following the stabilization of mesh use were extracted to compare the postoperative course including the pathology, symptom scores, surgical outcome, and recurrence of esophageal hiatus hernias. RESULTS: The preoperative conditions indicated that the degree of esophageal hiatal hernias was high in the mesh group (p = 0.0001), while the preoperative symptoms indicated that the score of heartburn was high in the non-mesh group (p = 0.0287). Although the surgical results indicated that the mesh group underwent a longer operation time (p < 0.0001) and a higher frequency of intraoperative complications (p = 0.037), the rate of recurrence of esophageal hiatal hernia was significantly low (p = 0.049), with the rate of postoperative reflux esophagitis also tending to be low (p = 0.083). CONCLUSIONS: Mesh reinforcement in laparoscopic fundoplication for esophageal hiatal hernias contributes to preventing the recurrence of esophageal hiatal hernias when it comes to patient options based on these criteria.


Asunto(s)
Esofagitis Péptica , Hernia Hiatal , Laparoscopía , Anciano , Humanos , Hernia Hiatal/complicaciones , Fundoplicación/métodos , Mallas Quirúrgicas , Laparoscopía/métodos , Esofagitis Péptica/complicaciones , Obesidad/complicaciones
7.
Sci Rep ; 13(1): 21805, 2023 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-38071246

RESUMEN

Chinese hamster ovary (CHO) cells are widely utilized in the production of antibody drugs. To ensure the production of large quantities of antibodies that meet the required specifications, it is crucial to monitor and control the levels of metabolites comprehensively during CHO cell culture. In recent years, continuous analysis methods employing on-line/in-line techniques using Raman spectroscopy have attracted attention. While these analytical methods can nondestructively monitor culture data, constructing a highly accurate measurement model for numerous components is time-consuming, making it challenging to implement in the rapid research and development of pharmaceutical manufacturing processes. In this study, we developed a comprehensive, simple, and automated method for constructing a Raman model of various components measured by LC-MS and other techniques using machine learning with Python. Preprocessing and spectral-range optimization of data for model construction (partial least square (PLS) regression) were automated and accelerated using Bayes optimization. Subsequently, models were constructed for each component using various model construction techniques, including linear regression, ridge regression, XGBoost, and neural network. This enabled the model accuracy to be improved compared with PLS regression. This automated approach allows continuous monitoring of various parameters for over 100 components, facilitating process optimization and process monitoring of CHO cells.


Asunto(s)
Técnicas de Cultivo de Célula , Espectrometría Raman , Cricetinae , Animales , Espectrometría Raman/métodos , Cricetulus , Células CHO , Teorema de Bayes , Técnicas de Cultivo de Célula/métodos , Anticuerpos , Aprendizaje Automático
8.
JVS Vasc Sci ; 4: 100123, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37662587

RESUMEN

Objective: Synchrotron radiation-based X ray phase-contrast tomography (XPCT) was used in this study to evaluate abdominal aorta specimens from patients with sac expansion without evidence of an endoleak (endotension) following endovascular aortic repair (EVAR) for an abdominal aortic aneurysm (AAA). The aim of this study was to analyze the morphologic structure of the aortic wall in patients with this condition and to establish the cause of the endotension. Methods: Human aortic specimens of the abdominal aorta were obtained during open repair, fixed with formalin, and analyzed among three groups. Group A was specimens from open abdominal aortic aneurysm repairs (n = 7). Group E was specimens from sac expansion without an evident endoleak after EVAR (n = 7). Group N was specimens from non-aneurysmal "normal" cadaveric abdominal aortas (n = 5). Using XPCT (effective voxel size, 12.5 µm; density resolution, 1 mg/cm3), we measured the density of the tunica media (TM) in six regions of each sample. Then, any changes to the elastic lamina and the vasa vasorum were analyzed pathologically. The specimens were immunohistochemically examined with anti-CD31 and vascular endothelial growth factor antibodies. Results: The time from EVAR to open aortic repair was 64.2 ± 7.2 months. There were significant differences in the thickness of the TM among three groups: 0.98 ± 0.03 mm in Group N; 0.31 ± 0.01 mm in Group A; and 0.15 ± 0.03 mm in Group E (P < .005). There were significant differences in the TM density among the groups: 1.087 ± 0.004 g/cm3 in Group N; 1.070 ± 0.001 g/cm3 in Group A; and 1.062 ± 0.007 g/cm3 in Group E (P < .005). Differences in the thickness and density of the TM correlated with the thickness of the elastic lamina; in Group N, uniform high-density elastic fibers were observed in the TM. By contrast, a thinning of the elastic lamina in the TM was observed in Group A. A marked thinness and loss of elastic fibers was observed in Group E. CD31 immunostaining revealed that the vasa vasorum was localized in the adventitia and inside the outer third of the TM in Group N, and in the middle of the TM in Group A. In Group E, the vasa vasorum advanced up to the intima with vascular endothelial growth factor-positive cells in the intimal section. Conclusions: XPCT could be used to demonstrate the densitometric property of the aortic aneurysmal wall after EVAR. We confirmed that the deformation process that occurs in the sac expansion after EVAR without evidence of an endoleak could be explained by hypoxia in the aortic wall.

9.
J Synchrotron Radiat ; 30(Pt 5): 995-1002, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37594861

RESUMEN

The link between the structural properties and the rupturing of chordae tendineae in the mitral valve complex is still unclear. Synchrotron-radiation-based X-ray phase computed tomography (SR-XPCT) imaging is an innovative way to quantitatively analyze three-dimensional morphology. XPCT has been employed in this study to evaluate the chordae tendineae from patients with mitral regurgitation and to analyze structural changes in the ruptured chordae tendineae in patients with this condition. Six ruptured mitral chordae tendineae were obtained during surgical repairs for mitral regurgitation and were fixed with formalin. In addition, 12 healthy chordae tendineae were obtained from autopsies. Employing XPCT (effective pixel size, 3.5 µm; density resolution, 1 mg cm-3), the density of the chordae tendineae in each sample was measured. The specimens were subsequently analyzed pathologically. The mean age was 70.2 ± 3.0 in the rupture group and 67.2 ± 14.1 years old in the control group (p = 0.4927). All scans of chorda tendineae with SR-XPCT were performed successfully. The mean densities were 1.029 ± 0.004 in the rupture group and 1.085 ± 0.015 g cm-3 in the control group (p < 0.0001). Density based on SR-XPCT in the ruptured mitral chordae tendineae was significantly lower compared with the healthy chorda tendinea. Histological examination revealed a change in the components of the connective tissues in ruptured chorda tendinea, in accordance with the low density measured by SR-XPCT. SR-XPCT made it possible to measure tissue density in mitral chordae tendineae. Low density in mitral chordae tendineae is associated with a greater fragility in ruptured mitral chordae tendineae.


Asunto(s)
Insuficiencia de la Válvula Mitral , Válvula Mitral , Humanos , Anciano , Persona de Mediana Edad , Anciano de 80 o más Años , Sincrotrones , Cuerdas Tendinosas , Rayos X , Tomografía Computarizada por Rayos X
10.
Sci Total Environ ; 902: 165957, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37543314

RESUMEN

Recent studies apparently finding deleterious effects of radiation exposure on cataract formation in birds and voles living near Chernobyl represent a major challenge to current radiation protection regulations. This study conducted an integrated assessment of radiation exposure on cataractogenesis using the most advanced technologies available to assess the cataract status of lenses extracted from fish caught at both Chernobyl in Ukraine and Fukushima in Japan. It was hypothesised that these novel data would reveal positive correlations between radiation dose and early indicators of cataract formation. The structure, function and optical properties of lenses were analysed from atomic to millimetre length scales. We measured the short-range order of the lens crystallin proteins using Small Angle X-Ray Scattering (SAXS) at both the SPring-8 and DIAMOND synchrotrons, the profile of the graded refractive index generated by these proteins, the epithelial cell density and organisation and finally the focal length of each lens. The results showed no evidence of a difference between the focal length, the epithelial cell densities, the refractive indices, the interference functions and the short-range order of crystallin proteins (X-ray diffraction patterns) in lens from fish exposed to different radiation doses. It could be argued that animals in the natural environment which developed cataract would be more likely, for example, to suffer predation leading to survivor bias. But the cross-length scale study presented here, by evaluating small scale molecular and cellular changes in the lens (pre-cataract formation) significantly mitigates against this issue.


Asunto(s)
Catarata , Accidente Nuclear de Chernóbil , Cristalinas , Animales , Dispersión del Ángulo Pequeño , Difracción de Rayos X , Catarata/etiología , Catarata/veterinaria , Catarata/metabolismo
11.
J Synchrotron Radiat ; 30(Pt 3): 627-633, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-37026390

RESUMEN

Palaeohistological analysis has numerous applications in understanding the palaeobiology of extinct dinosaurs. Recent developments of synchrotron-radiation-based X-ray micro-tomography (SXMT) have allowed the non-destructive assessment of palaeohistological features in fossil skeletons. Yet, the application of the technique has been limited to specimens on the millimetre to micrometre scale because its high-resolution capacity has been obtained at the expense of a small field of view and low X-ray energy. Here, SXMT analyses of dinosaur bones with widths measuring ∼3 cm under a voxel size of ∼4 µm at beamline BL28B2 at SPring-8 (Hyogo, Japan) are reported, and the advantages of virtual-palaeohistological analyses with large field of view and high X-ray energy are explored. The analyses provide virtual thin-sections visualizing palaeohistological features comparable with those obtained by traditional palaeohistology. Namely, vascular canals, secondary osteons and lines of arrested growth are visible in the tomography images, while osteocyte lacunae are unobservable due to their micrometre-scale diameter. Virtual palaeohistology at BL28B2 is advantageous in being non-destructive, allowing multiple sampling within and across skeletal elements to exhaustively test the skeletal maturity of an animal. Continued SXMT experiments at SPring-8 should facilitate the development of SXMT experimental procedures and aid in understanding the paleobiology of extinct dinosaurs.


Asunto(s)
Dinosaurios , Fósiles , Animales , Dinosaurios/anatomía & histología , Sincrotrones , Rayos X , Microtomografía por Rayos X/métodos
12.
Sci Rep ; 13(1): 5805, 2023 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-37037865

RESUMEN

Notwithstanding the various uses of rubber, the fracture mechanism of filler-reinforced rubber remains unclear. This study used four-dimensional computed tomography (4D-CT) involving monochromatic synchrotron X-rays to examine the cavitation within silica-reinforced rubber quantitatively and systematically. The results suggested a threshold value of silica content for the cavitation morphology. Macroscopic fractures, such as those developed by void formation, occurred below the threshold value of silica content. Above this threshold, the density of rubber decreased but macroscopic voids rarely occurred. The lower-density rubber area in the high-silica-content rubber was reversible at the effective pixel size for 4D-CT. These results suggest that the growth of the damage points to macrosized voids could be stopped by the formation of a network of rigid polymer layers. This study allows the elucidation of the reinforcing mechanism and the cavitation morphology of filler-reinforced rubber.

13.
Ann Gastroenterol Surg ; 7(2): 255-264, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36998304

RESUMEN

Aim: Osteopenia, characterized by low bone mineral density, is a potential prognostic factor for patients with cancer. The aim of this study was to clarify the impact of preoperative osteopenia in patients with gastric cancer (GC) after gastrectomy. Methods: We included 224 patients with GC who underwent gastrectomy between August 2013 and May 2022. Osteopenia was evaluated by measuring the pixel density in the mid-vertebral core of the 11th thoracic vertebra using computed tomography. Results: Osteopenia was identified in 68 patients (30%). The osteopenia group had significantly worse overall survival (OS) and disease-free survival (DFS) than the non-osteopenia group (P < .01, P < .01, respectively). The postoperative hospital stay was significantly longer, and the occurrence of postoperative complications (Clavien-Dindo grade ≥ III) was significantly higher in the osteopenia group (P = .04, P < .01, respectively). In multivariate analysis, osteopenia (P < .01), stage ≥II (P < .01), and R1 or R2 curability (P < .01) were independent and significant predictors of DFS. Additionally, osteopenia (P < .01), intraoperative blood loss (P = .04), stage ≥II (P < .01), and R1 or R2 curability (P < .01) were independent and significant predictors of OS. Conclusion: Preoperative osteopenia was independently associated with a poor prognosis and recurrence in patients who underwent gastrectomy for GC.

14.
J Synchrotron Radiat ; 30(Pt 2): 400-406, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36891853

RESUMEN

High-energy X-ray micro-laminography has been developed to observe inner- and near-surface structures in dense planar objects that are not suitable for observation by X-ray micro-tomography. A multilayer-monochromator-based high-intensity X-ray beam with energy of 110 keV was used for high-energy and high-resolution laminographic observations. As a demonstration of high-energy X-ray micro-laminography for observing dense planar objects, a compressed fossil cockroach on a planar matrix surface was analyzed with effective pixel sizes of 12.4 µm and 4.22 µm for wide field of view and high-resolution observations, respectively. In this analysis, the near-surface structure was clearly observed without undesired X-ray refraction-based artifacts from outside of the region of interest, a problem typical in tomographic observations. Another demonstration visualized fossil inclusions in a planar matrix. Micro-scale features of a gastropod shell and micro-fossil inclusions in the surrounding matrix were clearly visualized. When observing local structures in the dense planar object with X-ray micro-laminography, the penetrating path length in the surrounding matrix can be shortened. This is a significant advantage of X-ray micro-laminography where desired signals generated at the region of interest including optimal X-ray refraction effectively contribute to image formation without being disturbed by undesired interactions in the thick and dense surrounding matrix. Therefore, X-ray micro-laminography allows recognition of the local fine structures and slight difference in the image contrast of planar objects undetectable in a tomographic observation.

15.
Esophagus ; 20(3): 573-580, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36562858

RESUMEN

BACKGROUND: In recent years, the number of patients requiring surgery for intra-thoracic stomach (ITS) has been increasing due to the effects of obesity and gibbus due to aging. The aim of this study is to assess the effects of the degree of hernia on the pathological conditions and surgical outcomes in ITS patients. METHODS: ITS was defined as cases in which over 50% of the stomach had deviated into the mediastinum by esophagogastric fluoroscopy and/or computed tomography, with 65 patients who underwent laparoscopic surgery as the initial surgery included. We compared the pathological conditions and surgical outcomes by dividing the subjects into 3 groups: Group A: 50%- < 75%; Group B: 75%- < 100%; and Group C: 100% (upside-down stomach), depending on the degree of deviation into the mediastinum of the stomach. RESULTS: The breakdown of patients was 33 in Group A, 21 in Group B, and 11 in Group C. Regarding the preoperative pathological conditions, Group C had a high body mass index (BMI) and a low score for factor V according to upper gastrointestinal endoscopy (p = 0.0109, p = 0.0062, respectively). While the surgical results indicated that the operation time was extended depending on the degree of hernia (p = 0.0051), there was no marked difference in other surgical outcomes or the postoperative course among the three groups, with a high degree of satisfaction. CONCLUSIONS: In the case of ITS, although the operation time was extended depending on the degree of the hernia, the surgical outcomes were the same, and overall good results were obtained.


Asunto(s)
Hernia Hiatal , Laparoscopía , Humanos , Hernia Hiatal/complicaciones , Hernia Hiatal/cirugía , Laparoscopía/efectos adversos , Laparoscopía/métodos , Obesidad/complicaciones , Estómago/cirugía , Resultado del Tratamiento
16.
J Synchrotron Radiat ; 29(Pt 5): 1265-1272, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-36073886

RESUMEN

In this study, double-multilayer monochromators that generate intense, high-energy, pink X-ray beams are designed, installed and evaluated at the SPring-8 medium-length (215 m) bending-magnet beamline BL20B2 for imaging applications. Two pairs of W/B4C multilayer mirrors are designed to utilize photon energies of 110 keV and 40 keV with bandwidths of 0.8% and 4.8%, respectively, which are more than 100 times larger when compared with the Si double-crystal monochromator (DCM) with a bandwidth of less than 0.01%. At an experimental hutch located 210 m away from the source, a large and uniform beam of size 14 mm (V) × 300 mm (H) [21 mm (V) × 300 mm (H)] was generated with a high flux density of 1.6 × 109 photons s-1 mm-2 (6.9 × 1010 photons s-1 mm-2) at 110 keV (40 keV), which marked a 300 (190) times increase in the photon flux when compared with a DCM with Si 511 (111) diffraction. The intense pink beams facilitate advanced X-ray imaging for large-sized objects such as fossils, rocks, organs and electronic devices with high speed and high spatial resolution.


Asunto(s)
Fotones , Sincrotrones , Rayos X
17.
Microscopy (Oxf) ; 71(6): 364-373, 2022 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-35993532

RESUMEN

Land plants have two types of shoot-supporting systems, root system and rhizoid system, in vascular plants and bryophytes. However, since the evolutionary origin of the systems is different, how much they exploit common systems or distinct systems to architect their structures is largely unknown. To understand the regulatory mechanism of how bryophytes architect the rhizoid system responding to environmental factors, we have developed the methodology to visualize and quantitatively analyze the rhizoid system of the moss, Physcomitrium patens, in 3D. The rhizoids having a diameter of 21.3 µm on the average were visualized by refraction-contrast X-ray micro-computed tomography using coherent X-ray optics available at synchrotron radiation facility SPring-8. Three types of shape (ring-shape, line and black circle) observed in tomographic slices of specimens embedded in paraffin were confirmed to be the rhizoids by optical and electron microscopy. Comprehensive automatic segmentation of the rhizoids, which appeared in three different form types in tomograms, was tested by a method using a Canny edge detector or machine learning. The accuracy of output images was evaluated by comparing with the manually segmented ground truth images using measures such as F1 score and Intersection over Union, revealing that the automatic segmentation using machine learning was more effective than that using the Canny edge detector. Thus, machine learning-based skeletonized 3D model revealed quite dense distribution of rhizoids. We successfully visualized the moss rhizoid system in 3D for the first time.


Asunto(s)
Microtomografía por Rayos X
18.
Elife ; 112022 07 26.
Artículo en Inglés | MEDLINE | ID: mdl-35880746

RESUMEN

A crucial evolutionary change in vertebrate history was the Palaeozoic (Devonian 419-359 million years ago) water-to-land transition, allowed by key morphological and physiological modifications including the acquisition of lungs. Nonetheless, the origin and early evolution of vertebrate lungs remain highly controversial, particularly whether the ancestral state was paired or unpaired. Due to the rarity of fossil soft tissue preservation, lung evolution can only be traced based on the extant phylogenetic bracket. Here we investigate, for the first time, lung morphology in extensive developmental series of key living lunged osteichthyans using synchrotron x-ray microtomography and histology. Our results shed light on the primitive state of vertebrate lungs as unpaired, evolving to be truly paired in the lineage towards the tetrapods. The water-to-land transition confronted profound physiological challenges and paired lungs were decisive for increasing the surface area and the pulmonary compliance and volume, especially during the air-breathing on land.


All life on Earth started out under water. However, around 400 million years ago some vertebrates, such as fish, started developing limbs and other characteristics that allowed them to explore life on land. One of the most pivotal features to evolve was the lungs, which gave vertebrates the ability to breathe above water. Most land-living vertebrates, including humans, have two lungs which sit on either side of their chest. The lungs extract oxygen from the atmosphere and transfer it to the bloodstream in exchange for carbon dioxide which then gets exhaled out in to the atmosphere. How this important organ first evolved is a hotly debated topic. This is largely because lung tissue does not preserve well in fossils, making it difficult to trace how the lungs of vertebrates changed over the course of evolution. To overcome this barrier, Cupello et al. compared the lungs of living species which are crucial to understand the early stages of the water-to-land transition. This included four species of lunged bony fish which breathe air at the water surface, and a four-legged salamander that lives on land. Cupello et al. used a range of techniques to examine how the lungs of the bony fish and salamander changed shape during development. The results suggested that the lungs of vertebrates started out as a single organ, which became truly paired later in evolution once vertebrates started developing limbs. This anatomical shift increased the surface area available for exchanging oxygen and carbon dioxide so that vertebrates could breathe more easily on land. These findings provide new insights in to how the lung evolved into the paired structure found in most vertebrates alive today. It likely that this transition allowed vertebrates to fully adapt to breathing above water, which may explain why this event only happened once over the course of evolution.


Asunto(s)
Evolución Biológica , Agua , Animales , Peces/fisiología , Fósiles , Pulmón , Filogenia , Vertebrados
19.
Sci Rep ; 12(1): 13136, 2022 07 30.
Artículo en Inglés | MEDLINE | ID: mdl-35907977

RESUMEN

Maternal overnutrition affects offspring susceptibility to nonalcoholic steatohepatitis (NASH). Male offspring from high-fat diet (HFD)-fed dams developed a severe form of NASH, leading to highly vascular tumor formation. The cancer/testis antigen HORMA domain containing protein 1 (HORMAD1), one of 146 upregulated differentially expressed genes in fetal livers from HFD-fed dams, was overexpressed with hypoxia-inducible factor 1 alpha (HIF-1alpha) in hepatoblasts and in NASH-based hepatocellular carcinoma (HCC) in offspring from HFD-fed dams at 15 weeks old. Hypoxia substantially increased Hormad1 expression in primary mouse hepatocytes. Despite the presence of three putative hypoxia response elements within the mouse Hormad1 gene, the Hif-1alpha siRNA only slightly decreased hypoxia-induced Hormad1 mRNA expression. In contrast, N-acetylcysteine, but not rotenone, inhibited hypoxia-induced Hormad1 expression, indicating its dependency on nonmitochondrial reactive oxygen species production. Synchrotron-based phase-contrast micro-CT of the fetuses from HFD-fed dams showed significant enlargement of the liver accompanied by a consistent size of the umbilical vein, which may cause hypoxia in the fetal liver. Based on these findings, a maternal HFD induces fetal origins of NASH/HCC via hypoxia, and HORMAD1 is a potential therapeutic target for NASH/HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Enfermedad del Hígado Graso no Alcohólico , Animales , Dieta Alta en Grasa/efectos adversos , Feto/metabolismo , Hipoxia , Masculino , Ratones , Ratones Endogámicos C57BL , Enfermedad del Hígado Graso no Alcohólico/metabolismo
20.
World J Surg Oncol ; 20(1): 199, 2022 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-35698131

RESUMEN

BACKGROUND: Undifferentiated pleomorphic sarcoma (UPS) is a malignant soft tissue tumor that has been reclassified from malignant fibrous histiocytoma with the development of the pathological diagnosis. It principally occurs in the extremities but rarely occurs in the rectum. We herein report a rare case of UPS arising in the rectum. CASE PRESENTATION: A 85-year-old woman was referred to our hospital with a complaint of anal pain, which had persisted for several months. Computed tomography (CT) showed a 53 × 58 × 75 mm mass on the left side of the rectum. Colonoscopy revealed a submucosal elevation in the rectum without any exposure of the tumor to the surface. Contrast-enhanced CT and magnetic resonance imaging revealed an 80-mm mass that originated in the rectal muscular propria, and we suspected a gastrointestinal stromal tumor. No lymph node metastasis or distant metastasis was observed. We performed a laparoscopic Hartmann's operation. Intraoperatively, severe adhesion around the tumor caused tumor injury and right ureteral dissection. Thus, laparoscopic right ureteral anastomosis and ureteral stenting were additionally performed. The operation time was 6 h and 3 min, and the estimated blood loss was small. The patient was discharged without complications 25 days after surgery. A pathological examination showed that the tumor was composed of highly heterogeneous cells with no specific differentiation traits, leading to a diagnosis of UPS. Contrast-enhanced CT performed 2 months after surgery showed bilateral pelvic lymph node enlargement, which indicated recurrence. Considering the patient's age, we performed radiotherapy (50 Gy/25 Fr targeting the pelvic region). At present, 16 months have passed since the completion of radiotherapy. Contrast-enhanced CT shows that the recurrent lymph nodes have disappeared, and no new distant metastasis has been observed. CONCLUSIONS: We reported a case of UPS arising in the rectum. The surgical procedure and indication of preoperative therapy should be carefully selected because complete removal of the tumor is desirable in UPS.


Asunto(s)
Histiocitoma Fibroso Maligno , Sarcoma , Neoplasias de los Tejidos Blandos , Anciano de 80 o más Años , Femenino , Histiocitoma Fibroso Maligno/diagnóstico , Humanos , Pelvis/patología , Recto/patología , Recto/cirugía , Sarcoma/patología , Neoplasias de los Tejidos Blandos/cirugía
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