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991.
Liposomes incorporating polyethylene glycol (PEG)-conjugated lipids (PEGylated liposomes) have attracted attention as drug delivery carriers because they show good in vivo stability. The lipid component of PEGylated liposomal formulations needs to be quantified for quality control. In this study, a simple reversed-phase high-performance liquid chromatography (HPLC) method with an evaporative light-scattering detector (ELSD) was established for simultaneous determination of hydrogenated soy phosphatidylcholine, cholesterol, PEG-conjugated lipid, and hydrolysis products of phospholipid in PEGylated liposomal formulations. These lipids were separated using a C18 column with a gradient mobile phase consisting of ammonium acetate buffer and ammonium acetate in methanol at a flow rate of 1.0 ml/min. This method provided sufficient repeatability, linearity, and recovery rate for all lipids. However, the linearity and recovery rates of cholesterol achieved using a ultraviolet (UV) detector were better than those achieved using an ELSD. This validated method can be applied to assess the composition change during the preparation process of liposomes and to quantify lipid components and hydrolysis products contained in a commercially available liposomal formulation DOXIL®. Taken together, this reversed-phase HPLC-UV/ELSD method may be useful for the rapid or routine analysis of liposomal lipid components in process development and quality control. 相似文献
992.
Masanori Ito Yoshihide Yamanashi Yu Toyoda Hiroko Izumi-Nakaseko Satoko Oda Atsushi Sugiyama Masaru Kuroda Hiroshi Suzuki Tappei Takada Satomi Adachi-Akahane 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2013,1831(2):459-468
STARD10, a member of the steroidogenic acute regulatory protein (StAR)-related lipid transfer (START) protein family, is highly expressed in the liver and has been shown to transfer phosphatidylcholine. Therefore it has been assumed that STARD10 may function in the secretion of phospholipids into the bile. To help elucidate the physiological role of STARD10, we produced Stard10 knockout mice (Stard10−/−) and studied their phenotype. Neither liver content nor biliary secretion of phosphatidylcholine was altered in Stard10−/− mice. Unexpectedly, the biliary secretion of bile acids from the liver and the level of taurine-conjugated bile acids in the bile were significantly higher in Stard10−/− mice than wild type (WT) mice. In contrast, the levels of the secondary bile acids were lower in the liver of Stard10−/− mice, suggesting that the enterohepatic cycling is impaired. STARD10 was also expressed in the gallbladder and small intestine where the expression level of apical sodium dependent bile acid transporter (ASBT) turned out to be markedly lower in Stard10−/− mice than in WT mice when measured under fed condition. Consistent with the above results, the fecal excretion of bile acids was significantly increased in Stard10−/− mice. Interestingly, PPARα-dependent genes responsible for the regulation of bile acid metabolism were down-regulated in the liver of Stard10−/− mice. The loss of STARD10 impaired the PPARα activity and the expression of a PPARα-target gene such as Cyp8b1 in mouse hepatoma cells. These results indicate that STARD10 is involved in regulating bile acid metabolism through the modulation of PPARα-mediated mechanism. 相似文献
993.
Yoshikazu Yuki Mio Mejima Shiho Kurokawa Tomoko Hiroiwa Yuko Takahashi Daisuke Tokuhara Tomonori Nochi Yuko Katakai Masaharu Kuroda Natsumi Takeyama Koji Kashima Michiyo Abe Yingju Chen Ushio Nakanishi Takehiro Masumura Yoji Takeuchi Hiroko Kozuka‐Hata Hiroaki Shibata Masaaki Oyama Kunisuke Tanaka Hiroshi Kiyono 《Plant biotechnology journal》2013,11(7):799-808
Plants have been used as expression systems for a number of vaccines. However, the expression of vaccines in plants sometimes results in unexpected modification of the vaccines by N‐terminal blocking and sugar‐chain attachment. Although MucoRice‐CTB was thought to be the first cold‐chain‐free and unpurified oral vaccine, the molecular heterogeneity of MucoRice‐CTB, together with plant‐based sugar modifications of the CTB protein, has made it difficult to assess immunological activity of vaccine and yield from rice seed. Using a T‐DNA vector driven by a prolamin promoter and a signal peptide added to an overexpression vaccine cassette, we established MucoRice‐CTB/Q as a new generation oral cholera vaccine for humans use. We confirmed that MucoRice‐CTB/Q produces a single CTB monomer with an Asn to Gln substitution at the 4th glycosylation position. The complete amino acid sequence of MucoRice‐CTB/Q was determined by MS/MS analysis and the exact amount of expressed CTB was determined by SDS‐PAGE densitometric analysis to be an average of 2.35 mg of CTB/g of seed. To compare the immunogenicity of MucoRice‐CTB/Q, which has no plant‐based glycosylation modifications, with that of the original MucoRice‐CTB/N, which is modified with a plant N‐glycan, we orally immunized mice and macaques with the two preparations. Similar levels of CTB‐specific systemic IgG and mucosal IgA antibodies with toxin‐neutralizing activity were induced in mice and macaques orally immunized with MucoRice‐CTB/Q or MucoRice‐CTB/N. These results show that the molecular uniformed MucoRice‐CTB/Q vaccine without plant N‐glycan has potential as a safe and efficacious oral vaccine candidate for human use. 相似文献
994.
Itoh Kazuhiro Iwasaki Hiromichi Negoro Eiju Shigemi Hiroko Tokimatsu Issei Tsutani Hiroshi Yamauchi Takahiro 《Mycopathologia》2021,186(1):113-117
Mycopathologia - Invasive trichosporonosis is a rare and lethal fungal infection that occurs in immunocompromised patients. Breakthrough trichosporonosis can occur in patients treated with... 相似文献
995.
Mast cells play a crucial role in allergic inflammatory reactions through releasing cytosolic granules upon antigen stimulation. However, the mechanisms underlying maturation and release of secretory granules are not fully understood. We found that autophagy is constitutively induced in mast cells under full nutrition conditions, and type II LC3 (LC3-II), a marker for autophagosomes, localizes on secretory granules. While deletion of Atg7 does not impair the development of bone marrow-derived mast cells (BMMCs), Atg7-deficient BMMCs show severe impairment of degranulation, but not cytokine production, upon antigen stimulation. Moreover we found that LC3-II, but not LC3-I, colocalizes with CD63, a marker for secretory lysosomes and is released extracellularly along with degranulation in wild-type BMMCs, but not Atg7-deficient BMMCs. Finally, passive cutaneous anaphylaxis reactions are almost completely abolished in mast celldeficient mice reconstituted with Atg7-deficient BMMCs. Collectively, these results suggest that autophagy is not essential for the development, but plays a crucial role in degranulation, of mast cells. 相似文献
996.
Tanaka H Atsumi I Shirota O Sekita S Sakai E Sato M Murata J Murata H Darnaedi D Chen IS 《化学与生物多样性》2011,8(3):476-482
Two new isoflavonoids, eryvarins V and W (1 and 2, resp.), and a new chromen-4-one derivative, eryvarin X (3), along with three known isoflavonoids, 4-6, were isolated from the roots of Erythrina variegata. Their structures were established by spectroscopic analyses. Compound 1 is a rare naturally occurring isoflavanone which possesses a OH group at C(3). Among the new compounds 1-3, 2 exhibited a potent antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) strains. 相似文献
997.
998.
Kitamura K Fujiyoshi K Yamane J Toyota F Hikishima K Nomura T Funakoshi H Nakamura T Aoki M Toyama Y Okano H Nakamura M 《PloS one》2011,6(11):e27706
Many therapeutic interventions for spinal cord injury (SCI) using neurotrophic factors have focused on reducing the area damaged by secondary, post-injury degeneration, to promote functional recovery. Hepatocyte growth factor (HGF), which is a potent mitogen for mature hepatocytes and a mediator of the inflammatory responses to tissue injury, was recently highlighted as a potent neurotrophic factor in the central nervous system. We previously reported that introducing exogenous HGF into the injured rodent spinal cord using a herpes simplex virus-1 vector significantly reduces the area of damaged tissue and promotes functional recovery. However, that study did not examine the therapeutic effects of administering HGF after injury, which is the most critical issue for clinical application. To translate this strategy to human treatment, we induced a contusive cervical SCI in the common marmoset, a primate, and then administered recombinant human HGF (rhHGF) intrathecally. Motor function was assessed using an original open field scoring system focusing on manual function, including reach-and-grasp performance and hand placement in walking. The intrathecal rhHGF preserved the corticospinal fibers and myelinated areas, thereby promoting functional recovery. In vivo magnetic resonance imaging showed significant preservation of the intact spinal cord parenchyma. rhHGF-treatment did not give rise to an abnormal outgrowth of calcitonin gene related peptide positive fibers compared to the control group, indicating that this treatment did not induce or exacerbate allodynia. This is the first study to report the efficacy of rhHGF for treating SCI in non-human primates. In addition, this is the first presentation of a novel scale for assessing neurological motor performance in non-human primates after contusive cervical SCI. 相似文献
999.
Sakai D Kii I Nakagawa K Matsumoto HN Takahashi M Yoshida S Hosoya T Takakuda K Kudo A 《PloS one》2011,6(9):e24847
Background
The adaptive nature of bone formation under mechanical loading is well known; however, the molecular and cellular mechanisms in vivo of mechanical loading in bone formation are not fully understood. To investigate both mechanisms at the early response against mechanotransduction in vivo, we employed a noninvasive 3-point bone bending method for mouse tibiae. It is important to investigate periosteal woven bone formation to elucidate the adaptive nature against mechanical stress. We hypothesize that cell morphological alteration at the early stage of mechanical loading is essential for bone formation in vivo.Principal Findings
We found the significant bone formation on the bone surface subjected to change of the stress toward compression by this method. The histological analysis revealed the proliferation of periosteal cells, and we successively observed the appearance of ALP-positive osteoblasts and increase of mature BMP-2, resulting in woven bone formation in the hypertrophic area. To investigate the mechanism underlying the response to mechanical loading at the molecular level, we established an in-situ immunofluorescence imaging method to visualize molecules in these periosteal cells, and with it examined their cytoskeletal actin and nuclei and the extracellular matrix proteins produced by them. The results demonstrated that the actin cytoskeleton of the periosteal cells was disorganized, and the shapes of their nuclei were drastically changed, under the mechanical loading. Moreover, the disorganized actin cytoskeleton was reorganized after release from the load. Further, inhibition of onset of the actin remodeling blocked the proliferation of the periosteal cells.Conclusions
These results suggest that the structural change in cell shape via disorganization and remodeling of the actin cytoskeleton played an important role in the mechanical loading-dependent proliferation of cells in the periosteum during bone formation. 相似文献1000.
Takashima S Kanatsu-Shinohara M Tanaka T Takehashi M Morimoto H Shinohara T 《Cell Stem Cell》2011,9(5):463-475
The homing ability of spermatogonial stem cells (SSCs) allows them to migrate into niches after being transplantated into infertile testes. Transplanted SSCs attach to Sertoli cells and transmigrate through the blood-testis barrier (BTB), formed by inter-Sertoli tight junctions, toward niches on the basement membrane. The most critical step is the passage through the BTB, which limits the homing efficiency to <10%. Here we demonstrated the involvement of Rac1 in SSC transmigration. Rac1-deficient SSCs did not colonize the adult testes, but they reinitiated spermatogenesis when transplanted into pup testes without a BTB. Moreover, a dominant-negative Rac1 construct not only reduced the expression of several claudin proteins, which comprise the BTB, but also increased SSC proliferation both in vitro and in vivo. Short hairpin RNA (shRNA) -mediated suppression of claudin3, which was downregulated by Rac inhibition, reduced the SSC homing efficiency. Thus, Rac1 is a critical regulator of SSC homing and proliferation. 相似文献