Biomedical subjects
Publications and source records attributed to Masahiro Miura.
Alpha,alpha-disubstituted 3-thiophenemethanols undergo selective diarylation accompanied by cleavage of the C-H and C-C bonds of the 2- and 3-positions, respectively, upon treatment with aryl bromides in the presence of a palladium catalyst to give the corresponding 2,3-diarylthiophenes in good yields.
Lymphatic invasion is known as an independent predictor of lymph node metastasis in gastric cancer. However, the diagnosis of lymphatic invasion is sometimes difficult by hematoxylin-eosin (H&E) staining. Immunostaining using D2-40 was performed to study the distribution of lymphatic vessel and lymphatic invasion in a series of 78 primary gastric cancers. D2-40 showed specific staining for the lymphatic vessels, but not for blood vessels. The lymphatic invasion was most frequently found in the upper half of submucosal layer. Positive rate of lymphatic invasion by H&E staining was 27% (21/78), and that by D2-40 was 44% (34/78). Lymphatic invasion on H&E staining was diagnosed as false negative in 17 (21.8%) of 78 primary gastric cancers and false positive in 4 (5.1%) of 78 primary gastric cancers. Sensitivity for lymph node metastasis by the lymphatic invasion diagnosed by D2-40 was significantly higher (89%, 24/27) than by H&E staining (41%, 11/27). These results suggest that the diagnosis of lymphatic invasion by D2-40 is more sensitive than H&E staining. Sensitivity for the prediction of lymph node metastasis from the lymphatic invasion status in primary tumor by D2-40 was significantly higher than by H&E staining. Based on our results, we recommend the use of D2-40 immunoreactions for the routine evaluation of lymphatic invasion in gastric cancer.
The main osseous landmarks of the border area between the infratemporal fossa and the para- and retro pharyngeal space are the sphenoidal spine and the pterygoid and styloid processes, and the styloid vagina. These landmarks, as well as some vascular anomalies, were studied in order to illustrate the variable anatomy, which is encountered in the surgical lateral transzygomatic infratemporal fossa approach. Hundred well-preserved human skull bases were examined. The deep infratemporal fossa was dissected into 54 halves of fixed cadaveric head and neck specimens of both sexes. Dry skull specimens of New and Old World monkeys, skulls of rodents, herbivora and carnivora, and computed tomograms of the head of Macaca fuscata Japonica, were also studied. In 91 of the human skull bases, the sphenoidal spine was prominent and well developed. In three skulls, the spine was absent. In four specimens, however, the spine was not sphenoidal but a part of the temporal bone, occurring in the form of a process, which emanated from the styloid vagina. In two further cases, there was unilaterally a duplicated spine; the anterior part represented a regular sphenoidal spine, while the posterior part constituted a part of the vagina of the styloid process. A complete osseous bar, arch or lamina-connecting the posterior border of the lateral lamina of the pterygoid process and the sphenoidal spine-existed in six of the human dry skulls. In ten of the human skulls examined, the breadth of the lateral lamina of the pterygoid process was greater than 10 mm; thus, the so-called pterygospinous (ps) and the pterygostyloid gates-of significance where surgical approaches are concerned-were less than 10 mm in width. Fibrous or muscular connections were also found in some cadaveric specimens between the posterior border of the lateral lamina of the pterygoid process and the sphenoidal spine: a ps ligament existed in 11 cases (20.4%) and a ps muscle in 5 cases (9.2 %), in 3 of which it inserted into both the medial wall capsule and the articular disc of the temporo-mandibular joint. Among the cadaveric specimens exhibiting ps structures was one in which an osseous ps bar occurred together with a ps muscle; in two cases a strong ps ligament was observed together with a ps muscle. The distribution pattern of the mandibular nerve was affected by the positioning of the ps bar, ligament and muscle when the latter were present. The existence of a wide ps bar was noted in all the skulls of herbivora, rodentia, carnivora, and Old World monkeys that were examined, but never in those of the New World monkeys; it is likely that, in the human, this ps bar represents a phylogenetic remnant. In the human dry skull specimens and cadaveric material, the ps ligament was found to be a reinforcement of the interpterygoid fascia, and the ps muscle to be a third head of the lateral pterygoid muscle. In two cases, the internal carotid artery exhibited a significant elongation and space-consuming tortuosity (so-called coiling behavior) in the depth of the infratemporal fossa.
In recent years, several functional molecules specifically expressed and localized in lymphatic endothelial cells, such as 5'-nucleotidase, lymphatic vessel endothelial receptor-1, vascular endothelial growth factor receptor-3, podoplanin and Prox-1, have been identified. The discovery of the lymphatic endothelial cell markers facilitated detailed analysis of the nature and structural organization of the lymphatic vessels and their growth (lymphangiogenesis). As a result, over the past few years, advances have been made in understanding the cellular and molecular aspects of physiological lymphangiogenesis and tumor-induced lymphangiogenesis. The biology of lymphangiogenesis, particularly the mechanism of its regulation, is very important in understanding the formation of the lymphatic system as a biological regulation system transporting tissue fluid and wandering cells, including lymphocytes, and disease involving lymphangiogenesis. The understanding of the molecular mechanism of lymphangiogenesis and the elucidation of the development of normal and pathological tissues are expected to lead to the development of therapy for intractable diseases, such as malignant tumors and lymphedema.
1,1-Disubstituted 3-aryl-2-propyn-1-ols undergo unprecedented regio- and stereoselective homocoupling with liberation of a ketone molecule in the presence of a rhodium catalyst to give the corresponding 2-hydroxymethyl-(E)-enynes. The subsequent cyclization of the enynes in the presence of a base affords fluorescent 2,3-dihydrofuran derivatives.
[reaction: see text]. The Suzuki-Miyaura-type cross-coupling of arylboron compounds with aryl halides proceeds efficiently in the presence of a rhodium-based catalyst system to produce the corresponding biaryls. Furthermore, it has unexpectedly been observed that the treatment with benzonitrile under similar conditions brings about its multiple arylation, in which nucleophilic arylation on the cyano group and subsequent ortho arylation via C-H bond cleavage are involved.
[reaction: see text] The sequential three-component coupling of aryl iodides, diarylacetylenes, and monosubstituted alkenes effectively proceeds in the presence of Pd(OAc)(2), LiCl, and NaHCO(3) as catalyst, promoter, and base, respectively, in DMF-H(2)O to produce the corresponding 1,3-butadiene derivatives.
BACKGROUND: The molecular mechanisms of lymphangiogenesis induced by vascular endothelial growth factor (VEGF)-C and VEGF-D in gastric cancer were studied. METHODS: VEGF-C and VEGF-D gene expression vectors were transfected into the gastric cancer cell line KKLS, which did not originally express VEGF-C and VEGF-D, and stable transfectants (KKLS/VEGF-C and KKLS/VEGF-D) were established. The cell lines were inoculated into the subserosal layer of the stomach and subcutaneous tissue of nude mice. RESULTS: VEGF-C and VEGF-D expression in KKLS/VEGF-C and KKLS/VEGF-D cells was found by reverse transcription polymerase chain reaction (RT-PCR) and Western blot analysis. Expression of mouse VEGF receptor (VEGFR)-2 and mouse VEGFR-3 mRNA was detected in the KKLS/VEGF-C and KKLS/VEGF-D gastric tumors. Newly formed lymphatic vessels were detected not only in the periphery but also in the center of the tumors. The intratumor lymphatic vessels connected with the preexisting lymphatic vessels in the muscularis mucosa. The average numbers of lymphatic vessels in KKLS/VEGF-C (52.0 +/- 9.5) and KKLS/VEGF-D (16.4 +/- 0.6) gastric tumors were significantly higher than that in the KKLS/control vector tumors (4.0 +/- 1.4). CONCLUSION: VEGF-C and VEGF-D may induce neoformation of lymphatic vessels in experimental gastric tumors by the induction of VEGFR-3 expression.
PURPOSE: To evaluate a noninvasive technique to detect the leakage point of central serous chorioretinopathy (CSR), using a polarimetry method. DESIGN: Prospective cohort study. METHODS SETTING: Institutional practice. PATIENTS: We examined 30 eyes of 30 patients with CSR. MAIN OUTCOME MEASURES: Polarimetry images were recorded using the GDx-N (Laser Diagnostic Technologies). We computed four images that differed in their polarization content: a depolarized light image, an average reflectance image, a parallel polarized light image, and a birefringence image. Each polarimetry image was compared with abnormalities seen on fluorescein angiography. RESULTS: In all eyes, leakage area could be clearly visualized as a bright area in the depolarized light images. Michelson contrasts for the leakage areas were 0.58 +/- 0.28 in the depolarized light images, 0.17 +/- 0.11 in the average reflectance images, 0.09 +/- 0.09 in the parallel polarized light images, and 0.11 +/- 0.21 in the birefringence images from the same raw data. Michelson contrasts in depolarized light images were significantly higher than for the other three images (P < .0001, for all tests, paired t test). The fluid accumulated in the retina was well-visualized in the average and parallel polarized light images. CONCLUSIONS: Polarization-sensitive imaging could readily localize the leakage point and area of fluid in CSR. This may assist with the rapid, noninvasive assessment of CSR.
PURPOSE: To evaluate a spectral imaging technique to detect the area of internal limiting membrane (ILM) peeling after vitrectomy for idiopathic macular hole. MATERIALS AND METHODS: In a prospective study, 15 eyes of 15 patients with idiopathic macular holes were tested. After vitrectomy with ILM peeling, retinal images were taken with color fundus photography, red-free fundus photography, and scanning laser ophthalmoscope imaging at 488 nm, 514 nm, 633 nm, and 780 nm. We calculated the Michelson contrast at the margin of ILM peeling, and each image was rank ordered for the ability to discern the margin of ILM peeling. RESULTS: The Michelson contrasts in scanning laser ophthalmoscope images at 488 nm and 514 nm were significantly larger than those in images at 633 nm and 780 nm and in the red-free fundus photograph. The scanning laser ophthalmoscope images at 488 nm and 514 nm were rated superior to images at 633 nm and 780 nm, the color fundus photograph, and the red-free fundus photograph. CONCLUSION: The scanning laser ophthalmoscope images at 488 nm and 514 nm provide a better tool than some of the common clinical means for detection of the area of ILM peeling. This may assist with rapid, noninvasive assessment of ILM peeling.
Triarylmethanols are effectively dehydroarylated and reacted with some unsaturated compounds by using an appropriate palladium catalyst system such as Pd(OAc)2-P(1-Nap)3 (1-Nap = 1-naphthyl) to give the corresponding arenes and hydroarylation products, respectively, along with diaryl ketones.
Explore the source record for details and available documents.
2-Hydroxy-2-methylpropiophenone undergoes a unique multiple arylation via C-C and C-H bond cleavages upon treatment with excess aryl bromides in the presence of a palladium catalyst to give 1,1,2,2-tetraarylethanes and 4,4-diaryl-1-phenylisochroman-3-ones.
The vascular endothelial growth factor-C (VEGF-C), a specific lymphangiogenic growth factor, raises new questions and perspectives in studying lymphatic development and regeneration. Wound healing skins in mice were processed for 5'-nucleotidase (5'-Nase) and VEGFR-3 (the receptor of VEGF-C) histochemical staining to distinguish lymphatics from blood capillaries and to analyze lymphangiogenesis. In the wounds of 3-5 days after injury, anti-VEGFR-3 immunopositive signals unevenly appeared in 5'-Nase-positive lymphatic vessels in the subcutaneous tissue. A few small circular and irregular lymphatic-like structures with VEGFR-3 expression scattered in the dermal and subcutaneous tissues. Between days 7 and 15 of the wounds, numerous accumulated vasculatures were stained for 5'-Nase and PECAM-1, extending irregularly along the wound edge. Von Willebrand factor was expressed in the endothelial cells of blood vessels and lymphatics in the subcutaneous tissue. Ultrastructural changes of lymphatic vessels developed at different stages, from lymphatic-like structures to newly formed lymphatic vessels with an extremely thin and indented wall. Endothelial cells of the lymphatic vessel were eventually featured by typical intercellular junctions, which deposited with reaction products of VEGFR-3 and 5'-Nase-cerium but lacked VEGF-C expression. The present findings indicate that VEGF-C-induced lymphangiogenesis occurs from the subcutaneous to the dermis along the wound healing edge, especially in the dermal-subcutaneous transitional area, favorable to growth of regenerating lymphatic vessels.
Explore the source record for details and available documents.
The present study has investigated the relationship between pancreatic lymphatics, infiltrating cells, and insulitic development after a single injection of complete Freund's adjuvant (CFA) given at an early age in the nonobese diabetic (NOD) mice. No CFA-treated NOD mice developed hyperglycemia, whereas most CFA-untreated mice died of diabetes at the age of 20-30 weeks. In untreated NOD mice, the increased infiltration of dendritic cells (DCs) and T-lymphocytes into the pancreatic islets appeared to be consistent with the increased expression of the secondary lymphoid chemokine (CCL21) and CD(31) by the endothelial cell lining of inter- and intralobular lymphatics. As the infiltration became severe, the reaction products of CCL21 and CD(31) were distributed in the nucleus and cytoplasm of lymphatic endothelial cells (LECs), through which DCs and T-lymphocytes migrated frequently. Administration of CFA reduced the number of infiltrating DCs and T-lymphocytes, but did not affect macrophage infiltration. The peri-insulitis occurred in numerous islets of CFA-treated NOD mice without the appearance of the intraislet infiltration and islet-associated lymphoid-like tissues. Furthermore, significant suppression of CCL21 and CD(31) was demonstrated on the infiltrating cells to the islets and islet-associated lymphatics. The abluminal endothelial cell lining of lymphatic vessels exhibited weaker immunoreactivity of CCL21 and CD(31) in comparison with the luminal surfaces. The reaction product of 5'-nucleotidase (5'-Nase) was evenly deposited on LECs, which were the absence of open junctions, cytoplasmic protrusions, and vesicles. CFA treatment influenced the migratory processes of the infiltrating cell, which were closely related with structural changes of pancreatic lymphatics and inhibited insulitic development. These findings suggest that in CFA-treated NOD mice, the suppression of insulitis and prevention of diabetes are secondary to the functional modulation of pancreatic lymphatics and infiltrating cells.
PURPOSE: To determine the polarization properties of intraocular lenses (IOLs) in vitro and whether these properties contribute to significant intraindividual differences in the optical performance of the eye, including retinal imaging. SETTING: Tokyo Medical University, Shinjuku, Tokyo, Japan. METHODS: The single-pass linear birefringence was evaluated at 546.5 nm for the central 1.5 mm of the following IOLs: poly(methyl methacrylate) (MZ30BD, EZE55, UV-60SB, 824C, LS-106S), acrylic (MA60BM, VA-60CB, AR40e), and silicone (SI-40NB). To evaluate the influence of folding, models MA60BM, VA-60CB, AR40e, and SI-40NB were folded, unfolded, and measured for retardation values. To evaluate glistenings in vitro, experimental manipulation using the MA60BM was done to produce regions of glistenings. Retardation values were measured at the center of the micro-opacities and the adjacent clear areas. RESULTS: Striking polarization patterns were seen only in the compression-molded IOL, model 824C. Its retardation values ranged from 2.8 to 41.0 nm in the 30.0 diopter model. In other IOLs, the in vitro retardation values were minimal, even with folding, and barely nonuniform with glistening formation. CONCLUSIONS: The birefringence of the 824C IOL could be a source of error during polarization measurements of the fundus or with instruments that transmit polarized light through the IOL.
It has been documented that sucralfate, a basic aluminum salt, enhances the efficacies of antibiotics against Helicobacter pylori, resulting in eradication rates comparable to those associated with the use of proton pump inhibitors. However, its mechanism of action remains unclear. The aim of the present study was to investigate sucralfate's ability to complement antibiotic treatment of H. pylori infection in vivo. Four weeks following induced H. pylori infection, clarithromycin (CAM) and amoxicillin (AMPC) were administered orally to C57BL/6 mice for 5 days, both with and without sucralfate or lansoprazole. When sucralfate was concurrently given with CAM and AMPC at the maximum noninhibitory doses for the treatment of H. pylori infection, the bacterial clearance rates were comparable to those achieved by treatment with lansoprazole plus those antibiotics. The results of pharmacokinetic studies showed that lansoprazole delayed gastric clearance and accelerated the absorption of CAM, whereas sucralfate suppressed both gastric clearance and absorption. AMPC was undetectable in all samples. Scanning electron microscopy with a microscope to which a energy dispersive spectrometer was attached revealed that aluminum-containing aggregated substances coated the mucosa surrounding H. pylori in mice receiving sucralfate plus antibiotics, whereas the gastric surface and pits where H. pylori had attached were clearly visible in mice receiving lansoprazole plus antibiotics. The addition of sucralfate to the antibiotic suspension resulted in a more viscous mixture that bound to the H. pylori-infected mucosa and that inhibited the loss of CAM bioavailability in the acidic environment. Sucralfate delays gastric clearance of CAM and physically captures H. pylori through the creation of an adherent mucus, which leads to bacterial clearance.