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1.
Appl Opt ; 63(2): 423-428, 2024 Jan 10.
Article in English | MEDLINE | ID: mdl-38227238

ABSTRACT

We demonstrated a 40-MHz detection of spectroscopic polarization by a supercontinuum vector beam with a wavelength-dependent polarization state. To achieve the high-repetition-rate measurement, we detected the rotation angle of polarization and the spectrum by measuring the temporal waveform using a photodetector after expanding the pulse duration of the supercontinuum vector beam. The spectrum of the supercontinuum vector beam was measured using a spectrometer. We compared it with the temporal waveforms, confirming a good agreement of spectra between the conventional spectrometer and the temporal waveforms. The detection method is useful for many applications requiring high-repetition-rate spectroscopic-polarization measurements, such as the defect inspection of thin optical materials.

2.
J Appl Microbiol ; 134(9)2023 Sep 05.
Article in English | MEDLINE | ID: mdl-37660239

ABSTRACT

AIMS: Enzymatic degradation of ß-1,4-linked glucose and glucosamine (glucosaminoglucan, GG), which is prepared from Thiothrix nivea and can act as a cellulose-aminating agent with a strong affinity to cellulose, was attempted. METHODS AND RESULTS: A chitosanase-secreting fungal strain was isolated as a GG-degrading microbe. GG was found to be degraded by not only chitosanases but also cellulases. Based on nuclear magnetic resonance spectroscopy, both enzymes were found to produce GlcN-Glc from GG. The cellulases also produced GlcN-Glc-GlcN-Glc as an additional final digest. Furthermore, aminated (GG-coated) cellulose nanofibers exhibited cellulase resistance. The flexibility of GG adsorbed onto a cellulose crystal was almost identical to that of cellulose, as estimated via the molecular dynamics calculations. CONCLUSIONS: The chitosanase and cellulase hydrolyzed the ß-1,4-linkage from Glc to GlcN and were expected to recognize the tetramer and hexamer units of GG depending on their final products. The cellulose nanofibers acquired cellulase resistance via amination with GG, probably because of the lower activity of cellulase to GG than cellulose.


Subject(s)
Cellulase , Nanofibers , Biological Transport , Cellulose , Glucose
3.
Opt Express ; 30(24): 43491-43502, 2022 Nov 21.
Article in English | MEDLINE | ID: mdl-36523045

ABSTRACT

A counter-propagating laser-beam platform using a spherical plasma mirror was developed for the kilojoule-class petawatt LFEX laser. The temporal and spatial overlaps of the incoming and redirected beams were measured with an optical interferometer and an x-ray pinhole camera. The plasma mirror performance was evaluated by measuring fast electrons, ions, and neutrons generated in the counter-propagating laser interaction with a Cu-doped deuterated film on both sides. The reflectivity and peak intensity were estimated as ∼50% and ∼5 × 1018 W/cm2, respectively. The platform could enable studies of counter-streaming charged particles in high-energy-density plasmas for fundamental and inertial confinement fusion research.

4.
Phys Rev Lett ; 127(16): 165001, 2021 Oct 15.
Article in English | MEDLINE | ID: mdl-34723597

ABSTRACT

Ablative Rayleigh-Taylor instability growth was investigated to elucidate the fundamental physics of thermal conduction suppression in a magnetic field. Experiments found that unstable modulation growth is faster in an external magnetic field. This result was reproduced by a magnetohydrodynamic simulation based on a Braginskii model of electron thermal transport. An external magnetic field reduces the electron thermal conduction across the magnetic field lines because the Larmor radius of the thermal electrons in the field is much shorter than the temperature scale length. Thermal conduction suppression leads to spatially nonuniform pressure and reduced thermal ablative stabilization, which in turn increases the growth of ablative Rayleigh-Taylor instability.

5.
PLoS One ; 16(11): e0260121, 2021.
Article in English | MEDLINE | ID: mdl-34793564

ABSTRACT

To determine the optimal soil sample size for microbial community structure analysis, DNA extraction, microbial composition analysis, and diversity assessments were performed using soil sample sizes of 0.2, 1, and 5 g. This study focused on the relationship between soil amount and DNA extraction container volume and the alteration in microbial composition at different taxonomic ranks (order, class, and phylum). Horizontal (0.2 and 1 g) and vertical (5 g) shaking were applied during DNA extraction for practical use in a small laboratory. In the case of the 5 g soil sample, DNA extraction efficiency and the value of α-diversity index fluctuated severely, possibly because of vertical shaking. Regarding the 0.2 and 1 g soil samples, the number of taxa, Shannon-Wiener index, and Bray-Curtis dissimilarity were stable and had approximately the same values at each taxonomic rank. However, non-metric multidimensional scaling showed that the microbial compositions of these two sample sizes were different. The higher relative abundance of taxa in the case of the 0.2 g soil sample might indicate that cell wall compositions differentiated the microbial community structures in these two sample sizes due to high shear stress tolerance. The soil sample size and tube volume affected the estimated microbial community structure. A soil sample size of 0.2 g would be preferable to the other sample sizes because of the possible higher shearing force for DNA extraction and lower experimental costs due to smaller amounts of consumables. When the taxonomic rank was changed from order to phylum, some minor taxa identified at the order rank were integrated into major taxa at the phylum rank. The integration affected the value of the ß-diversity index; therefore, the microbial community structure analysis, reproducibility of structures, diversity assessment, and detection of minor taxa would be influenced by the taxonomic rank applied.


Subject(s)
DNA/isolation & purification , Microbiota/genetics , Specimen Handling/methods , Biomechanical Phenomena/physiology , Multidimensional Scaling Analysis , Reproducibility of Results , Sample Size , Soil/chemistry , Soil Microbiology
6.
Phys Rev E ; 103(3-1): 033201, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33862682

ABSTRACT

We report on the experimental investigation of magnetic field generation with a half-loop gold sheet coil driven by long-duration (10 ns) and high-power (0.5 TW) laser pulses. The amplitude of the magnetic field was characterized experimentally using proton deflectometry. The field rises rapidly in the first 1 ns of laser irradiation, and then increases slowly and continuously up to 10 ns during further laser irradiation. The transient dynamics of current shape were investigated with a two-dimensional (2D) numerical simulation that included Ohmic heating of the coil and the resultant change of electrical resistivity determined by the coil material temperature. The numerical simulations show rapid heating at the coil edges by current initially localized at the edges. This current density then diffuses to the central part of the sheet coil in a way that depends both on normal current diffusion as well as temporal changes of the coil resistance induced by the Ohmic heating. The measured temporal evolution of the magnetic field is compared with a model that determines a solution to the coil current and voltage that is consistent with a plasma diode model of the drive region and a 2D simulation of current diffusion and dynamic resistance due to Ohmic heating in the laser coil.

7.
Chem Commun (Camb) ; 57(17): 2124-2127, 2021 Mar 01.
Article in English | MEDLINE | ID: mdl-33538748

ABSTRACT

Tripodal ligands have been utilized for complexation-induced structural change, but all the tripodal complexes reported so far are facial isomers, which do not completely reduce the recognition ability by closing the binding pocket. We now report the first example of the selective synthesis of a meridional tripodal complex. The tripodal ligand with a 1,3,5-triethyl-2,4,6-tris(methylene)benzene pivot possessing 2,2'-bipyridine on each arm exclusively formed a mononuclear complex with the mer-[Fe(bpy)]2+ unit. The meridional tripodal complex has a unique structure in which one bipyridine unit is self-penetrated. As a result of cavity blockage, the ion recognition property of the tripodand has been successfully suppressed.

8.
Phys Rev Lett ; 124(3): 035001, 2020 Jan 24.
Article in English | MEDLINE | ID: mdl-32031862

ABSTRACT

Fast isochoric laser heating is a scheme to heat matter with a relativistic intensity (>10^{18} W/cm^{2}) laser pulse for producing an ultrahigh-energy-density (UHED) state. We have demonstrated an efficient fast isochoric heating of a compressed dense plasma core with a multipicosecond kilojoule-class petawatt laser and an assistance of externally applied kilotesla magnetic fields for guiding fast electrons to the dense plasma. A UHED state of 2.2 PPa is achieved experimentally with 4.6 kJ of total laser energy that is one order of magnitude lower than the energy used in the conventional implosion scheme. A two-dimensional particle-in-cell simulation confirmed that diffusive heating from a laser-plasma interaction zone to the dense plasma plays an essential role to the efficient creation of the UHED state.

9.
Sci Rep ; 9(1): 14115, 2019 Oct 01.
Article in English | MEDLINE | ID: mdl-31575943

ABSTRACT

The quantum yield of graphene quantum dots was enhanced by restriction of the rotation and vibration of surface functional groups on the edges of the graphene quantum dots via esterification with benzyl alcohol; this enhancement is crucial for the widespread application of graphene quantum dots in light-harvesting devices and optoelectronics. The obtained graphene quantum dots with highly graphene-stacked structures are understood to participate in π-π interactions with adjacent aromatic rings of the benzylic ester on the edges of the graphene quantum dots, thus impeding the nonradiative recombination process in graphene quantum dots. Furthermore, the crude graphene quantum dots were in a gel-like solid form and showed white luminescence under blue light illumination. Our results show the potential for improving the photophysical properties of nanomaterials, such as the quantum yield and band-gap energy for emission, by controlling the functional groups on the surface of graphene quantum dots through an organic modification approach.

10.
Pathol Int ; 69(1): 29-36, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30688413

ABSTRACT

The clinicopathological and immunohistochemical characteristics of clinically occult extrapulmonary lymphangioleiomyomatosis in lymph nodes (LN-LAM) being dissected during surgical staging of pelvic malignancy have not been well investigated. We assessed samples from nine female patients (median age, 61). None had past or familial history of tuberous sclerosis and had LAM lesions other than LN such as lung. The primary malignancies included four endometrial endometrioid carcinomas, one endometrial carcinosarcoma, three ovarian serous carcinomas and one urothelial carcinoma. Median follow-up was 43 months. The number of affected LNs ranged from 1 to 15 (median, 2) with sizes ranging from 1 to 13 mm (median, 3.0). Six cases had clinically occult LN-LAM only within the pelvic LNs, two only within para-aortic LNs, and one within both pelvic and para-aortic lymph nodes. Immunohistochemically, LAM cells exhibited a strong diffuse positivity for ß-catenin and E-cadherin in all nine cases. Clinically occult LN-LAM mainly affects peri- or post-menopausal women. On rare occasions, occult LN-LAM may manifest as systemic LAM, including in the lung. ß-catenin and E-cadherin carry potential utility as additional diagnostic markers.


Subject(s)
Biomarkers, Tumor/metabolism , Carcinoma, Endometrioid/pathology , Endometrial Neoplasms/pathology , Lymphangioleiomyomatosis/pathology , Pelvic Neoplasms/pathology , Adult , Aged , Cadherins/metabolism , Carcinoma, Endometrioid/metabolism , Endometrial Neoplasms/metabolism , Female , Humans , Immunohistochemistry , Lymph Nodes/pathology , Lymphangioleiomyomatosis/metabolism , Middle Aged , Pelvic Neoplasms/metabolism , Pelvis/pathology , beta Catenin/metabolism
11.
Nat Commun ; 9(1): 3937, 2018 09 26.
Article in English | MEDLINE | ID: mdl-30258053

ABSTRACT

Fast isochoric heating of a pre-compressed plasma core with a high-intensity short-pulse laser is an attractive and alternative approach to create ultra-high-energy-density states like those found in inertial confinement fusion (ICF) ignition sparks. Laser-produced relativistic electron beam (REB) deposits a part of kinetic energy in the core, and then the heated region becomes the hot spark to trigger the ignition. However, due to the inherent large angular spread of the produced REB, only a small portion of the REB collides with the core. Here, we demonstrate a factor-of-two enhancement of laser-to-core energy coupling with the magnetized fast isochoric heating. The method employs a magnetic field of hundreds of Tesla that is applied to the transport region from the REB generation zone to the core which results in guiding the REB along the magnetic field lines to the core. This scheme may provide more efficient energy coupling compared to the conventional ICF scheme.

12.
Case Rep Obstet Gynecol ; 2018: 4931852, 2018.
Article in English | MEDLINE | ID: mdl-29607235

ABSTRACT

Tamoxifen treatment for breast cancer may induce ovarian cysts and supraphysiological levels of serum estrogen. We report successful management with luteinizing hormone-releasing hormone (LHRH) agonist of ovarian hyperstimulation induced by tamoxifen. A 49-year-old woman was operated on for invasive ductal carcinoma of the right breast. She received breast irradiation and adjuvant tamoxifen therapy. After 2 years, she had a cystic ovarian mass, and her serum concentration of estradiol was 1280 pg/mL. She was treated with an injection of 11.25 mg leuprolide acetate, a long-acting LHRH agonist, without abandoning tamoxifen therapy. The levels of estradiol decreased to <10 pg/mL and the cystic mass disappeared 2 months later. Three-month depot treatment with LHRH agonists can be useful for patients receiving tamoxifen for breast cancer who have ovarian cysts and supraphysiological levels of estrogen.

14.
Int J Gynecol Pathol ; 34(6): 584-9, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26447356

ABSTRACT

Epithelial-mesenchymal transition is a key process influencing cancer progression and metastasis. The purpose of this study was to investigate the expression of epithelial-mesenchymal transition-related factors in chorionic villi and decidual cells in adherent placenta. The current study included 19 patients diagnosed with adherent placenta after hysterectomy. The expression of E-cadherin, Vimentin, Snail, and transforming growth factor-ß in placental tissues was analyzed by immunohistochemical staining. Immunostaining intensity was semiquantitatively evaluated using the HSCORE algorithm. In the chorionic villi of the invasive part (placenta with invasion into myometrium), E-cadherin expression was significantly lower than that in the noninvasive part (placenta with no invasion). In the decidual cells of the invasive part, expression of transforming growth factor-ß and Snail significantly increased. These results suggest that epithelial-mesenchymal transition may contribute to excessive trophoblast invasion into the myometrium in adherent placenta.


Subject(s)
Biomarkers/analysis , Epithelial-Mesenchymal Transition/physiology , Placenta Accreta/pathology , Adult , Female , Humans , Immunohistochemistry , Pregnancy
15.
Mol Clin Oncol ; 3(4): 785-788, 2015 Jul.
Article in English | MEDLINE | ID: mdl-26171180

ABSTRACT

Breast cancer growth is dependent on time and it may be of utmost importance to take into consideration the duration of clinical symptoms in order to predict which patients are at high risk for disease recurrence. The aim of this study was to determine the association between duration of clinical symptoms and disease recurrence in patients with breast cancer. A total of 139 consecutive patients with primary breast cancer who underwent a radical breast operation were retrospectively investigated and the association between recurrence and the duration of symptoms was investigated. The duration of clinical signs was defined as the time from the onset of symptoms to the date of surgery. The breast cancer cases were divided into two groups on the basis of symptom duration (≤6 and >6 months). The mean duration of symptoms was 191.0±242.6 days. Of the 139 cases, 36 (25.9%) had a duration of symptoms of >6 months. In the univariate analysis, a statistically significant association with long symptom duration was observed for disease recurrence. Of the 139 patients, 6 (4.3%) developed recurrent disease. The univariate analysis revealed that long duration of symptoms and nuclear grade were significantly associated with recurrence. In conclusion, our results indicated that breast cancer progression is dependent on time. A long duration of symptoms (>6 months) may be considered as an indicator of tumor progression and a strong prognostic factor in breast cancer patients.

16.
Am Surg ; 81(5): 523-6, 2015 May.
Article in English | MEDLINE | ID: mdl-25975340

ABSTRACT

The presence of lymph node metastasis is considered to be the most significant indicator of prognosis. However, in some cases with node-positive breast cancer, cancer cell dissemination is localized to the lymphatic systems. It is, therefore, important to develop selection criteria for strong adjuvant therapy in patients with node-positive breast cancer. This study was undertaken to evaluate the presence of vascular invasion that may reflect systemic disease as a predictor of disease recurrence in node-positive breast cancer. We retrospectively evaluated the cases of 134 consecutive female patients with breast cancer with lymph node metastasis who underwent radical breast operations. We examined the relationship between recurrence and clinicopathological factors, particularly vascular invasion. The presence of vascular invasion was found to be significant in a univariate analysis. The presence of vascular invasion was the independent risk factor in a multivariate analysis. Among the 66 patients without vascular invasion, four (6.1%) had disease recurrence. On the other hand, among the 68 patients with vascular invasion, 15 (22.1%) had a recurrence. It is interesting to note that despite the presence of lymph node metastasis, the group without vascular invasion had few patients with distant metastases. Our results suggest that the presence of vascular invasion could be an indicator of high biological aggressiveness and may be a strong prognostic factor for node-positive breast cancer.


Subject(s)
Breast Neoplasms/epidemiology , Breast Neoplasms/pathology , Neoplasm Recurrence, Local/epidemiology , Vascular Neoplasms/pathology , Female , Humans , Lymphatic Metastasis , Middle Aged , Neoplasm Invasiveness , Retrospective Studies , Risk Factors
17.
Anticancer Res ; 35(6): 3581-4, 2015 Jun.
Article in English | MEDLINE | ID: mdl-26026130

ABSTRACT

BACKGROUND/AIM: Lymphatic invasion (ly) may mainly reflect the selective affinity of breast cancer cells for lymph nodes. We conducted the present study to investigate whether the presence of lymphatic invasion is a predictor of sentinel lymph node (SLN) metastasis in clinically node-negative breast cancer. PATIENTS AND METHODS: We retrospectively evaluated the cases of 202 consecutive female patients with clinically node-negative primary breast cancer who underwent a radical breast operation with SLN biopsy. We examined the relationship between SLN metastasis and the significance of clinicopathological factors, including lymphatic invasion. RESULTS: Among the 202 patients, 49 (24.3%) had SLN metastasis. The univariate and multivariate analyses revealed that the size of the tumor and lymphatic invasion were independent risk factors for SLN metastasis. Among the 96 patients who were ly-negative and had a tumor size of less than 20 mm, only 5 (5.2%) had 1-2 metastases within the SLN. Among the 34 patients who were ly-negative and had a tumor size of less than 10 mm, there were no patients with SLN metastasis. CONCLUSION: Our results suggest that the presence of lymphatic invasion combined with the size of the primary cancer could be considered a strong risk factor for SLN metastasis in clinically node-negative breast cancer, and patients with a tumor size of less than 20 mm and clinically node-negative breast cancer may avoid axillary lymph node dissection after SLN biopsy. There is also a possibility that SLN biopsy could be unnecessary for patients with clinically node-negative breast cancer who are ly-negative and have a tumor size of less than 10 mm.


Subject(s)
Breast Neoplasms/pathology , Lymphatic Metastasis/pathology , Neoplasm Invasiveness/pathology , Adult , Aged , Breast Neoplasms/surgery , Female , Humans , Lymph Node Excision , Middle Aged , Risk Factors , Sentinel Lymph Node Biopsy
18.
Plast Reconstr Surg Glob Open ; 3(3): e315, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25878926

ABSTRACT

Cloacal exstrophy is an extremely rare congenital complex deformity that is associated with anterior abdominal wall defects, reflex and exposure of the cloaca (uninterrupted ureter and bowel), aproctia, a widely separated pubic bone, and defects or dysplasia of external genital organs. Here, we present the case of a 42-year-old man with squamous cell carcinoma arising from an abdominal wall defect complicated by cloacal exstrophy. He was successfully treated with excision of the skin lesion with the bowel and reconstruction using a pedicled anterolateral thigh flap combined with a tensor fasciae latae flap. To our knowledge, this is the first report of squamous cell carcinoma arising from an abdominal wall defect complicated by cloacal exstrophy.

19.
Hepatogastroenterology ; 62(138): 283-5, 2015.
Article in English | MEDLINE | ID: mdl-25916049

ABSTRACT

BACKGROUND/AIMS: Inflammatory reactions are par- tially responsible for postoperative ileus (POI). Serum C-reactive protein (CRP) is an acknowledged marker of inflammation. In this study the CRP response with respect to POI in elective colorectal surgery was exam- ined to define the role of serum CRP as an early predic- tor of POI. METHODOLOGY: Three hundred eighty-three patients who underwent elective colorectal resection were identified for inclusion in this study. We defined early POI as that occurring within 30 days following the surgery. Thirty-five patients with POI were com- pared to a subgroup of 348 patients with an unevent- ful postoperative course, and the correlation between postoperative serum CRP levels and POI in colorectal surgery was investigated. RESULTS: In the univariate analysis, length of operation, surgical blood loss, and serum CRP were factors significantly associated with POI following colorectal surgery; however, these fac- tors lost their significance on multivariate analysis. CONCLUSION: Our results suggest that an increase in CRP levels alone is not a predictor for POI following surgery for colorectal surgery. Although inflammatory responses are known to contribute to the ileus, ad- ditional study is required to identify risk factors that would be more useful for prediction of POI.


Subject(s)
C-Reactive Protein/analysis , Colorectal Neoplasms/surgery , Digestive System Surgical Procedures/adverse effects , Ileus/blood , Inflammation Mediators/blood , Aged , Aged, 80 and over , Biomarkers/blood , Blood Loss, Surgical , Colorectal Neoplasms/pathology , Elective Surgical Procedures , Female , Humans , Ileus/diagnosis , Ileus/etiology , Male , Middle Aged , Multivariate Analysis , Operative Time , Predictive Value of Tests , Retrospective Studies , Risk Factors , Time Factors , Treatment Outcome , Up-Regulation
20.
Nihon Hinyokika Gakkai Zasshi ; 106(4): 274-9, 2015 Oct.
Article in Japanese | MEDLINE | ID: mdl-26717787

ABSTRACT

A 41-year-old man with a history of cloacal exstrophy presented to a local clinic with abdominal pain and bowel sounds. He was noted to have pain at the site of scarring due to cloacal exstrophy and a laceration at its center, which was stained with feces. He was referred to our department because of an enterocutaneous fistula. Skin biopsy of the neoplastic lesion at this site led to a diagnosis of squamous cell carcinoma. Computed tomography showed tumor invasion of the ileum and right inguinal lymph node enlargement. We performed tumor resection, partial enterectomy, intestinal anastomosis, abdominal wall reconstruction with a left pedicled anterolateral thigh flap, split-thickness skin grafting, and right inguinal lymph node biopsy. Histopathological examination revealed cancer growth, invasion, and pearl formation in the lymph nodes, leading to a diagnosis of abdominal squamous cell carcinoma with metastasis to the inguinal lymph nodes. The skin graft took well, and the patient was discharged. He is scheduled for right inguinal lymph node dissection at a later date.


Subject(s)
Anus, Imperforate/complications , Carcinoma, Squamous Cell/complications , Colonic Neoplasms/complications , Adult , Anorectal Malformations , Carcinoma, Squamous Cell/pathology , Colonic Neoplasms/pathology , Colonic Neoplasms/surgery , Humans , Lymph Node Excision , Lymph Nodes/pathology , Lymphatic Metastasis , Male , Neoplasm Invasiveness , Tomography, X-Ray Computed
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