Publications by authors named "Koichi Shimizu"

Introduction: We evaluated the efficacy and safety of brexpiprazole for the treatment of agitation in Alzheimer's dementia (AAD) in Japanese patients.

Methods: This was a phase 2/3 multicenter, randomized, double-blind, placebo-controlled, parallel-group study. Patients with AAD were randomized to receive brexpiprazole 1 mg/day or 2 mg/day, or placebo (3:4:4) for 10 weeks.

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Introduction: The purpose of this study was to investigate the effects of nitrate and nitrite on the pH-lowering activity of human plaque, the nitrite-producing and -degrading activities of human plaque, and their correlation.

Methods: Nitrate and nitrite were added to human plaque suspensions collected from the buccal aspect of maxillary molars of patients visiting a general dental clinic, and changes in pH were measured with and without glucose addition. Nitrite-producing and -degrading activities were evaluated by adding nitrate and nitrite to the plaque suspension and measuring the increase and decrease in nitrite with Griess reagent, respectively.

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In our earlier research, a technique was developed to estimate the effective attenuation coefficient of subcutaneous blood vessels from the skin surface using the spatial distribution of backscattered near-infrared (NIR) light. The scattering effect in surrounding tissues was suppressed through the application of a differential principle, provided that the structure is known. In this study, a new method is proposed enabling the separate estimation of both scattering and absorption coefficients using NIR light of different wavelengths.

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Purpose: This study aimed to elucidate the relationship between diurnal masseter muscle activity and awareness of diurnal awake bruxism (d-AB) by conducting a comparative analysis of electromyographic (EMG) data from individuals with and without awareness of diurnal awake bruxism (d-AB), utilizing EMG data gathered from multiple subjects.

Methods: Unilateral masseter electromyography (EMG) recordings were performed during the daytime using an ultraminiature wearable EMG device. A total of 119 participants (59 with awareness of diurnal tooth clenching [d-TC] and 60 without awareness of d-TC) were included.

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For the study of biological effects of direct current (DC) and extremely low frequency (ELF) electric fields, we have quantitatively analyzed red blood cell (RBC) movement in whole blood. Considering the inhomogeneous distribution of electric fields in vivo, five different electric field distributions were generated under a microscope. For theoretical analyses, we assumed electrophoresis and dielectrophoresis as basic motive forces and obtained the spatial distribution of blood cell velocity.

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The classical transillumination technique has been revitalized through recent advancements in optical technology, enhancing its applicability in the realm of biomedical research. With a new perspective on near-axis scattered light, we have harnessed near-infrared (NIR) light to visualize intricate internal light-absorbing structures within animal bodies. By leveraging the principle of differentiation, we have extended the applicability of the Beer-Lambert law even in cases of scattering-dominant media, such as animal body tissues.

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To provide another modality for three-dimensional (3D) medical imaging, new techniques were developed to reconstruct a 3D structure in a turbid medium from a single blurred 2D image obtained using near-infrared transillumination imaging. One technique uses 1D information of a curvilinear absorber, or the intensity profile across the absorber image. Profiles in different conditions are calculated by convolution with the depth-dependent point spread function (PSF) of the transillumination image.

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Article Synopsis
  • This study explored how red blood cells (RBCs) move when exposed to direct current (DC) and alternating current (AC) extremely low frequency (ELF) electric fields.
  • Using a microscopic setup, researchers recorded RBC movement and analyzed their velocity in response to different electric field strengths.
  • Findings indicated that RBCs moved towards the electric field in DC exposure and followed the field gradient in AC exposure; DC contributed linearly to RBC velocity while AC had a quadratic relationship, with the required electric field strength exceeding standard safety guidelines by a factor of 10^-10.
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The objective of this review is to evaluate the anti-dementia activities of saffron and its combination with Kampo medicine. The Kampo formula Kamiuntanto composed of 13 crude drugs is well known for its anti-dementia activity. A significant increase in choline acetyltransferase activity and mRNA levels were observed.

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Patients with pancreatic ductal adenocarcinoma (PDAC) that have a history of other primary malignancies are not well documented. The current study therefore aimed to evaluate the clinicopathological characteristics of patients with PDAC with or without a history of other primary malignancies. A total of 102 patients with surgically treated PDAC that presented with or without a history of other primary malignancies were retrospectively analyzed.

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Using near-infrared (NIR) light with 700-1200 nm wavelength, transillumination images of small animals and thin parts of a human body such as a hand or foot can be obtained. They are two-dimensional (2D) images of internal absorbing structures in a turbid medium. A three-dimensional (3D) see-through image is obtainable if one can identify the depth of each part of the structure in the 2D image.

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Background: Immune related cells are known to be closely related to the therapeutic effects and prognoses of cancer patients. In this study, we analyzed immune cell profiles (ICP) of cholangiocarcinoma patients (CCA).

Methods: To measure the frequency of immune cells, peripheral blood mononuclear cells of 41 CCA and 10 healthy volunteers (HV) were analyzed by FACS.

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We report a case of a gastrointenstinal stromal tumor(GIST)of the small intestine with extraluminal growth that was difficult to distinguish from an ovarian tumor. A 73-year-old woman presented to a nearby hospital for lower abdominal pain. A computed tomography(CT)scan showed a 17 cm ovarian tumor in the pelvis, and she was referred to the gynecology department of our hospital.

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We experienced 3 cases of upper gastric cancer who underwent BillrothⅠ reconstruction in laparoscopy assisted subtotal gastrectomy. Two cases were female and 1 was male. The postoperative course was uneventful in all cases without heartburn, and the surgical margin was negative.

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Background: Postoperative pancreatic fistula (POPF) after pancreatoduodenectomy greatly influences patients' postoperative course. Several evaluation methods have been used to assess the risk of clinically relevant POPF (CR-POPF) after pancreatoduodenectomy namely, the original, alternative, and updated alternative fistula risk scores (o-FRS, a-FRS, and ua-FRS, respectively).

Methods: We enrolled 106/179 patients who underwent pancreatoduodenectomy in our institution between April 2013 and Mar 2018.

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For transillumination imaging of animal tissues, we have attempted to suppress the scattering effect in a turbid medium using the time-reversal principle of phase-conjugate light. We constructed a digital phase-conjugate system to enable intensity modulation and phase modulation. Using this system, we clarified the effectiveness of the intensity information for restoration of the original light distribution through a turbid medium.

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An octogenarian man complaining of bloody stool was referred to our hospital. A digital examination, abdominal enhanced CT and endoscopy led to a diagnosis of intussusception due to rectosigmoid colon cancer, but he was not suffering from bowel obstruction. An elective laparoscopic Hartmann's operation was performed after reduction by transanal insertion of a circular sizer.

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A 16-year-old castrated male mongrel cat presented with swelling under the left pinna and a 3 -month history of voice change. Laryngeal endoscopy revealed circumferential oedema around the arytenoid cartilages and hypersecretion of saliva. Histopathological examination of the mass around the left ear canal was considered the primary lesion that originated from cutaneous apocrine adenocarcinoma or parotid gland adenocarcinoma, and it metastasized to the larynx, lung and medial retropharyngeal lymph nodes.

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We present a case in which we used a thoracoscopic approach for resection of multiple esophageal carcinomas diagnosed 33 years after surgery for esophageal achalasia. A 68-year-old Japanese man had been diagnosed with esophageal achalasia and underwent surgical treatment 33 years earlier. He was examined at our hospital for annual routine checkup in which upper gastrointestinal endoscopy showed a "0-IIb+IIa" lesion in the middle esophagus.

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Background: Sclerosing mesenteritis is a non-neoplastic inflammatory disease that occurs in the bowel mesentery. Distinguishing sclerosing mesenteritis from neoplasms may be difficult because of the clinical and radiographic similarities between the two disease entities.

Case Presentation: We report a case of sclerosing mesenteritis mimicking peritoneal metastases of colorectal carcinoma.

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A spontaneous medaka ro mutant shows abnormal wobbling and rolling swimming behaviors. By positional cloning, we mapped the ro locus to a region containing the gene encoding Contactin1b (Cntn1b), which is an immunoglobulin (Ig)-superfamily domain-containing membrane-anchored protein. The ro mutant had a deletion in the cntn1b gene that introduced a premature stop codon.

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The aim of this study was to discover a simple/convenient geometrical arrangement of radiation sources and detector to acquire finger-photoplethysmograms (PPGs) with wavelength regions of blood glucose (BGL) absorption, toward practical noninvasive BGL measurement. First, we compared PPGs with three wavelengths: 808 nm (without water absorption), 1160 nm (with weak water absorption), and 1600 nm (with nearly peak BGL absorption and strong water absorption), while the source-detector spacing was successively increased circumferentially around a fingertip. In 10 healthy subjects, we observed clear cardiac-related pulsatile components of PPG signals at 808 and 1160 nm in any incident positions with more than 15 dB of signal-to-noise ratio ( S / N ), but reliable PPG detections at 1600 nm with more than 10 dB of S / N was only possible when the source-detector distance was less than 3 mm around the fingertip circumference.

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