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41.
Naoki Utsunomiya Suranant Subhadrabandhu Keizo Yonemori Masayoshi Oshida Shinya Kanzaki Fumiaki Nakatsubo Akira Sugiura 《Economic botany》1998,52(4):343-351
Diospyros species distributed widely in Thailand were classified into four ecotypes, according to their habitat; constantly humid area,
alternately dry and wet area, mountainous cool area and all area. Some of them inhabit near dwelling areas or in the paddy
field in the village. The young fruit is covered with dense pubescence in most species. The size, shape, and color of mature
fruit greatly vary greatly with the species. In most species, the mature fruit has a soft pulp and hard skin. The fruit of
six species has been used for dying. Four species produce edible fruits, with color and flavor favorable for breeding of edibleDiospyros species. The fruit of some species contains some chemicals useful as fish poisoning or of medicines, although the active
components have not yet been identified. The edible fruit contained many tannin cells, but the fruit used as fish poisoning
and medicines had only a few. 相似文献
42.
Nathan W Brunner Roham T Zamanian Fumiaki Ikeno Yoshiaki Mitsutake Andrew J Connolly Eric Shuffle Ke Yuan Mark Orcholski Jennifer Lyons Vinicio A de Jesus Perez 《Comparative medicine》2015,65(3):217-224
Pulmonary arterial hypertension (PAH) is a devastating disorder characterized by progressive elevation of the pulmonary pressures that, in the absence of therapy, results in chronic right-heart failure and premature death. The vascular pathology of PAH is characterized by progressive loss of small (diameter, less than 50 μm) peripheral pulmonary arteries along with abnormal medial thickening, neointimal formation, and intraluminal narrowing of the remaining pulmonary arteries. Vascular pathology correlates with disease severity, given that hemodynamic effects and disease outcomes are worse in patients with advanced compared with lower-grade lesions. Novel imaging tools are urgently needed that demonstrate the extent of vascular remodeling in PAH patients during diagnosis and treatment monitoring. Optical coherence tomography (OCT) is a catheter-based intravascular imaging technique used to obtain high-resolution 2D and 3D cross-sectional images of coronary arteries, thus revealing the extent of vascular wall pathology due to diseases such as atherosclerosis and in-stent restenosis; its utility as a diagnostic tool in the assessment of the pulmonary circulation is unknown. Here we show that OCT provides high-definition images that capture the morphology of pulmonary arterial walls in explanted human lungs and during pulmonary arterial catheterization of an adult pig. We conclude that OCT may facilitate the evaluation of patients with PAH by disclosing the degree of wall remodeling present in pulmonary vessels. Future studies are warranted to determine whether this information complements the hemodynamic and functional assessments routinely performed in PAH patients, facilitates treatment selection, and improves estimates of prognosis and outcome.Abbreviations: OCT, optical coherence tomography; PAC, pulmonary artery catheter; PAH, pulmonary arterial hypertensionPulmonary arterial hypertension (PAH) is a devastating disorder characterized by progressive elevation of pulmonary pressures that, when untreated, can lead to chronic right heart failure and death.14 The vascular pathology of PAH is characterized by neointimal formation, medial thickening, intravascular thrombi and, in severe cases, intravascular clusters of disorganized endothelial cells that give rise to tortuous endovascular channels.8 Most of the early vascular lesions are found in small (diameter, less than 50 μm) pulmonary arteries. However, as the disease advances, pulmonary arteries (diameter, 50 μm or larger) proximal to these lesions also display evidence of luminal narrowing and medial thickening.7,8,15 Most patients with PAH are younger than those with chronic systemic vascular disorders (that is, coronary artery disease, peripheral vascular disease, systemic hypertension), whose vascular pathology involves mostly large to medium-sized arteries. However, both patient populations demonstrate various pathologic features, including vascular smooth-cell accumulation, neointimal formation, inflammation, luminal narrowing, and alterations in the composition of the extracellular matrix.6,17The only definite way to diagnose PAH is through right heart catheterization to directly measure the pressure in the pulmonary circulation. Although pulmonary angiography during right heart catheterization cannot be used to diagnose PAH, it provides supportive evidence of PAH by demonstrating significant peripheral small vessel loss and luminal narrowing in the remaining central vessels. Angiography can help clinicians visualize pulmonary vessels in real time, but this diagnostic technique has important limitations. The use of ionized contrast can cause allergic reactions and may trigger acute renal failure due to contrast-induced nephropathy.26 In addition, pulmonary angiography provides information regarding gross vessel appearance and small vessel perfusion but not about the state of vascular wall remodeling or the extent of luminal narrowing associated with PAH at any stage.5,16 Therefore, imaging techniques are urgently needed that complement the hemodynamic information obtained via right heart catheterization with a safe and reproducible method to assess vascular wall pathology, thereby allowing clinicians to correlate the clinical evolution of PAH with the progression of vascular pathology.The last decade has seen tremendous progress in the development of intravascular imaging modalities that can identify patients at risk for developing complications related to systemic vascular disease and therefore prevent disease-related morbidity and mortality.4 One such modality is optical coherence tomography (OCT), an imaging technique that uses a thin (diameter, 1.0 mm) wire and near-infrared light to capture micrometer-resolution, 3D images from within optical scattering media (for example, biologic tissue).1 Superior to other intravascular imaging techniques, OCT is frequently used in patients with coronary artery disease, where it provides high-resolution images of the coronary arterial wall that correlate highly with pathology seen in explanted vessels.10,11,21 To date, several small studies have demonstrated the application of OCT to the evaluation of vascular remodeling in both idiopathic PAH and chronic thromboembolic PAH.7,21 However, despite OCT''s obvious advantages in the characterization of vascular remodeling in discrete segments of the pulmonary circulation, whether OCT provides anatomic information across the length of the pulmonary artery has not been tested.Here, we report the capacity of OCT to obtain both longitudinal and cross-sectional images that provide accurate anatomic information on healthy pulmonary arteries in explanted human lungs and during the pulmonary arterial catheterization of a live adult pig (Sus scrofa domesticus). 相似文献
43.
Yasuhiko Murata Takako Yasuda Tomomi Watanabe-Asaka Shoji Oda Akiko Mantoku Kazuhiro Takeyama Masahiro Chatani Akira Kudo Satoko Uchida Hiromi Suzuki Fumiaki Tanigaki Masaki Shirakawa Koichi Fujisawa Yoshihiko Hamamoto Shuji Terai Hiroshi Mitani 《PloS one》2015,10(10)
To understand how humans adapt to the space environment, many experiments can be conducted on astronauts as they work aboard the Space Shuttle or the International Space Station (ISS). We also need animal experiments that can apply to human models and help prevent or solve the health issues we face in space travel. The Japanese medaka (Oryzias latipes) is a suitable model fish for studying space adaptation as evidenced by adults of the species having mated successfully in space during 15 days of flight during the second International Microgravity Laboratory mission in 1994. The eggs laid by the fish developed normally and hatched as juveniles in space. In 2012, another space experiment (“Medaka Osteoclast”) was conducted. Six-week-old male and female Japanese medaka (Cab strain osteoblast transgenic fish) were maintained in the Aquatic Habitat system for two months in the ISS. Fish of the same strain and age were used as the ground controls. Six fish were fixed with paraformaldehyde or kept in RNA stabilization reagent (n = 4) and dissected for tissue sampling after being returned to the ground, so that several principal investigators working on the project could share samples. Histology indicated no significant changes except in the ovary. However, the RNA-seq analysis of 5345 genes from six tissues revealed highly tissue-specific space responsiveness after a two-month stay in the ISS. Similar responsiveness was observed among the brain and eye, ovary and testis, and the liver and intestine. Among these six tissues, the intestine showed the highest space response with 10 genes categorized as oxidation–reduction processes (gene ontogeny term GO:0055114), and the expression levels of choriogenin precursor genes were suppressed in the ovary. Eleven genes including klf9, klf13, odc1, hsp70 and hif3a were upregulated in more than four of the tissues examined, thus suggesting common immunoregulatory and stress responses during space adaptation. 相似文献
44.
Chiharu Suzuki-Nakagawa Misa Nishimura Tomoko Tsukamoto Sho Aoyama Akio Ebihara Fumiaki Suzuki Tsutomu Nakagawa 《Biochemical and biophysical research communications》2014
The (pro)renin receptor [(P)RR] induces the catalytic activation of prorenin, as well as the activation of the mitogen-activated protein kinase (MAPK) signaling pathway; as such, it plays an important regulatory role in the renin–angiotensin system. (P)RR is known to form a homodimer, but the region participating in its dimerization is unknown. Using glutathione S-transferase (GST) as a carrier protein and a GST pull-down assay, we investigated the interaction of several (P)RR constructs with full-length (FL) (P)RR in mammalian cells. GST fusion proteins with FL (P)RR (GST-FL), the C-terminal M8-9 fragment (GST-M8-9), the extracellular domain (ECD) of (P)RR (GST-ECD), and the (P)RR ECD with a deletion of 32 amino acids encoded by exon 4 (GST-ECDd4) were retained intracellularly, whereas GST alone was efficiently secreted into the culture medium when transiently expressed in COS-7 cells. Immunofluorescence microscopy showed prominent localization of GST-ECD to the endoplasmic reticulum. The GST pull-down analysis revealed that GST-FL, GST-ECD, and GST-ECDd4 bound FLAG-tagged FL (P)RR, whereas GST-M8-9 showed little or no binding when transiently co-expressed in HEK293T cells. Furthermore, pull-down analysis using His-tag affinity resin showed co-precipitation of soluble (P)RR with FL (P)RR from a stable CHO cell line expressing FL h(P)RR with a C-terminal decahistidine tag. These results indicate that the (P)RR ECD participates in dimerization. 相似文献
45.
Fumiaki Abe Masamichi Muto Tomoko Yaeshima Keiji Iwatsuki Hiroaki Aihara Yuji Ohashi Tomohiko Fujisawa 《Anaerobe》2010,16(2):131-136
Although probiotic-containing nutrient formulas for infants and toddlers have become very popular, some adverse effects related to translocation of probiotic strains have been reported. We assessed the safety of probiotic bifidobacteria that have been used in clinical investigations and proven to have beneficial effects, by analyzing mucin degradation activity and translocation ability. Mucin degradation activities of three probiotic bifidobacteria strains; Bifidobacterium longum BB536, Bifidobacterium breve M-16V and Bifidobacterium infantis M-63, were evaluated by three in vitro tests comprising growth in liquid medium, SDS-PAGE analysis of degraded mucin residues, and degradation assay in Petri dish. All test strains and control type strains failed to grow in the liquid medium containing mucin as the only carbon source, although good growth was obtained from fecal sample. In the SDS-PAGE analyses of mucin residues and observation of mucinolytic zone in agar plate, the three test strains also showed no mucin degradation activity as the type strains, although fecal sample yielded positive results. In another study, a high dose of B. longum BB536 was administered orally to conventional mice to examine the translocation ability. No translocation into blood, liver, spleen, kidney and mesenteric lymph nodes was observed and no disturbance of epithelial cells and mucosal layer in the ileum, cecum and colon was detected, indicating that the test strain had no translocation ability and induced no damage to intestinal surface. These results resolve the concern about bacterial translocation when using bifidobacteria strains as probiotics, which have been tested in various clinical trials, supporting the continuous use of these probiotic strains without anxiety. 相似文献
46.
47.
A mutualistic symbiosis between a dark septate endophytic fungus, Heteroconium chaetospira, and a nonmycorrhizal plant, Chinese cabbage 总被引:2,自引:0,他引:2
Symbiotic microorganisms, such as mycorrhizal fungi, are known to associate with most plants; however members of the Cruciferae are an exception. We investigated nutrient exchange between a dark septate endophytic fungus, Heteroconium chaetospira, and Chinese cabbage plants (Cruciferae) in vitro. Chinese cabbage could not use some amino acids, while the fungus-treated plants were able to use all of the nitrogen forms provided. To demonstrate that nitrogen transfer occurs between the fungus and the host plant, we used a hydrophobic polytetrafluoroethylene (PTFE) membrane compartment system, which restricts diffusion and mass flow of ions and allows only fungal penetration. Our results strongly suggest that H. chaetospira provided nitrogen to the plant, rather than the plant mineralizing available organic nitrogen. In addition carbon transfer from the host plant to the fungus was demonstrated with HPLC and (l3)CO2-labeling experiments. When H. chaetospira colonized host plant roots under low glucose condition, ergosterol content in culture pot (as an index of fungal biomass) increased significantly compared to the fungal treatment without a host plant. Sucrose concentration in the host root significantly decreased as a result of fungal colonization, and mannitol (a specific carbon source to fungal cells) increased in the roots. Sucrose and mannitol in the host root treated with the fungus were labeled clearly by 13C after 1C-labeled CO2 was provided to the plant. These results suggest that the fungus obtained carbon, mainly as sucrose, from the host plant. We show for the first time the existence of a fungus establishing a mutualistic association with a nonmycorrhizal Cruciferae plant. 相似文献
48.
49.
Saito F Masaki T Saito Y Nakamura A Takeda S Shimizu T Toda T Matsumura K 《Journal of neurochemistry》2007,101(6):1712-1722
Dystroglycan is a central component of the dystrophin-glycoprotein complex that links the extracellular matrix with cytoskeleton. Recently, mutations of the genes encoding putative glycosyltransferases were identified in several forms of congenital muscular dystrophies accompanied by brain anomalies and eye abnormalities, and aberrant glycosylation of alpha-dystroglycan has been implicated in their pathogeneses. These diseases are now collectively called alpha-dystroglycanopathy. In this study, we demonstrate that peripheral nerve myelination is defective in the fukutin-deficient chimeric mice, a mouse model of Fukuyama-type congenital muscular dystrophy, which is the most common alpha-dystroglycanopathy in Japan. In the peripheral nerve of these mice, the density of myelinated nerve fibers was significantly decreased and clusters of abnormally large non-myelinated axons were ensheathed by a single Schwann cell, indicating a defect of the radial sorting mechanism. The sugar chain moiety and laminin-binding activity of alpha-dystroglycan were severely reduced, while the expression of beta1-integrin was not altered in the peripheral nerve of the chimeric mice. We also show that the clustering of acetylcholine receptor is defective and neuromuscular junctions are fragmented in appearance in these mice. Expression of agrin and laminin as well as the binding activity of alpha-dystroglycan to these ligands was severely reduced at the neuromuscular junction. These results demonstrate that fukutin plays crucial roles in the myelination of peripheral nerve and formation of neuromuscular junction. They also suggest that defective glycosylation of alpha-dystroglycan may play a role in the impairment of these processes in the deficiency of fukutin. 相似文献