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41.
The patients were one-month-old identical twins. Scaly erythema was noted mainly on the trunk, face, and scalp of one twin starting about three weeks after birth and starting about two weeks after birth in the other. The patients' courses were observed without treatment; the eruptions tended to disappear two months after birth. The mother had a past history of transient facial erythema. Both twins and mother were positive for anti-nuclear antibody, anti-SS-A antibody, and anti-SS-B antibody. The histopathological findings corresponded to those of discoid lupus erythematosus (DLE). The class of HLA typing revealed Cw3 in both twins, which is frequently observed in neonatal lupus erythematosus (NLE), and A24 in the mother, which is frequently observed in mothers of babies with NLE. 相似文献
42.
Shuntaro Kouda Ryuichi Kuwahara Masaru Ohara Masanobu Shigeta Tamaki Fujiwara Hitoshi Komatsuzawa Tsuguru Usui Motoyuki Sugai 《Journal of infection and chemotherapy》2007,13(4):276-277
We report here the first isolation in Japan of a carbapenem-resistant Pseudomonas aeruginosa strain that carries the metallo-β-lactamase gene bla
IMP-7. This isolate revealed high-level resistance to all of the tested antibiotics except for piperacillin, showing a multidrug-resistant
phenotype. 相似文献
43.
Sushil Lathwal Saigopalakrishna S. Yerneni Susanne Boye Upenyu L. Muza Shuntaro Takahashi Naoki Sugimoto Albena Lederer Subha R. Das Phil G. Campbell Krzysztof Matyjaszewski 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(2)
Exosomes are emerging as ideal drug delivery vehicles due to their biological origin and ability to transfer cargo between cells. However, rapid clearance of exogenous exosomes from the circulation as well as aggregation of exosomes and shedding of surface proteins during storage limit their clinical translation. Here, we demonstrate highly controlled and reversible functionalization of exosome surfaces with well-defined polymers that modulate the exosome’s physiochemical and pharmacokinetic properties. Using cholesterol-modified DNA tethers and complementary DNA block copolymers, exosome surfaces were engineered with different biocompatible polymers. Additionally, polymers were directly grafted from the exosome surface using biocompatible photo-mediated atom transfer radical polymerization (ATRP). These exosome polymer hybrids (EPHs) exhibited enhanced stability under various storage conditions and in the presence of proteolytic enzymes. Tuning of the polymer length and surface loading allowed precise control over exosome surface interactions, cellular uptake, and preserved bioactivity. EPHs show fourfold higher blood circulation time without altering tissue distribution profiles. Our results highlight the potential of precise nanoengineering of exosomes toward developing advanced drug and therapeutic delivery systems using modern ATRP methods.Exosomes are a subclass of lipid bilayer-enclosed extracellular vesicles (EVs) that play a crucial role in intercellular communication (1–3). They are secreted by most cell types in the body and are known to interact with recipient cells in several ways, including surface receptor interactions, membrane fusion, receptor-mediated endocytosis, phagocytosis and/or micropinocytosis (4, 5). Their nanoscopic size (30 to 150 nm), high biocompatibility, low immunogenicity (depending on the cell source), and ability to cross biological barriers, including the blood–brain barrier, make them an ideal vehicle for exogenous drug delivery (6–9). Over the last decade, multiple studies have shown effective utility of exosomes for the delivery of small molecule drugs, proteins, nucleic acids and nanoparticles for the treatment of several diseases (10–12). Although initial progress toward their clinical translation has been made, the need for a more robust platform persists. The therapeutic potential of exosomes is largely restricted due to their low exogenous drug-loading efficiency and limited ex vivo stability (13, 14). Moreover, systemically administered exosomes suffer from rapid clearance from blood in 2 to 20 min postinjection that is poorly suited for longer therapeutic action (15, 16).Engineering exosomes to incorporate nonnative moieties or materials can augment their therapeutic capabilities (17–19). While bioengineering methods by genetically modifying the exosome-secreting cells have been explored, such approaches require careful design and expensive reagents, yet suffer from low incorporation efficiency and limited scalability. Alternatively, ex vivo engineering of exosome surfaces with synthetic macromolecules is a powerful approach to easily modulate their surface interactions and consequently alter or enhance their biochemical and physicochemical properties.Here, we create a polymer-based platform that expands the structural repertoire of engineered exosomes and addresses the shortcomings of the ex vivo and in vivo stability of exosome-based therapeutics. We combine our previously reported method for rapid and on-demand functionalization of exosomes through DNA tethers (20) with atom transfer radical polymerization (ATRP) techniques (21–23) to engineer exosome polymer hybrids (EPHs). These EPHs display significantly enhanced stability and pharmacokinetics. We explore the preparation methods for EPHs by either tethering preformed DNA block copolymers (DNABCPs) onto the exosome membrane (“grafting-to”) or by grafting polymers directly from the exosomal surface (“grafting-from”) (Fig. 1) using DNA initiators. These membrane-tethering approaches allow precise control over the polymer length, composition, and loading on the exosome surface and thereby show minimal effect on the accessibility of surface proteins or other membrane-tethered agents that may be used for targeted delivery. We show that the cellular uptake and bioactivity of native and drug-loaded exosomes are preserved following polymer functionalization. Tethered polymers enhance the stability of exosomes under different storage conditions, including in the presence of proteolytic enzymes. The blood circulation half-lives of EPHs are significantly increased using different polymers, while maintaining their intrinsic tissue-targeting properties.Open in a separate windowFig. 1.Preparation of EPHs using DNA tethers. Chol-DNA embeds into the exosome membrane to form Exo-ssDNA (single-stranded DNA) species with DNA strands orienting outward. Hybridization of complementary DNA block copolymer (DNA′-Polymer) to the DNA tethers on Ex-ssDNA species generates Exo-dsDNA-Polymer (Exo-Polymer) by the “grafting-to” strategy. Alternatively, for the “grafting-from” strategy, a complementary DNA initiator (DNA′-Initiator) functionalized with the α-bromoisobutyrate group is hybridized with the DNA tethers, followed by surface-initiated ATRP to prepare Exo-Polymer species. 相似文献
44.
Shuntaro Oka Hiroyuki Okudaira Masahiro Ono David M. Schuster Mark M. Goodman Keiichi Kawai Yoshifumi Shirakami 《Molecular imaging and biology》2014,16(3):322-329
Purpose
We aimed to elucidate trans-1-amino-3-[18F]fluorocyclobutanecarboxylic acid (anti-[18F]FACBC) uptake mechanisms in inflammatory and tumor cells, in comparison with those of l-[methyl-11C]methionine ([11C]Met) and 2-deoxy-2-[18F]fluoro-d-glucose ([18F]FDG).Procedures
Using carbon-14-labeled tracers, in vitro time-course, pH dependence, and competitive inhibition uptake experiments were performed in rat inflammatory (T cells, B cells, granulocytes, macrophages), prostate cancer (MLLB2), and glioma (C6) cells.Results
Anti-[14C]FACBC uptake ratios of T/B cells to tumor cells were comparable, while those of granulocytes/macrophages to tumor cells were lower than those for [14C]FDG. Over half of anti-[14C]FACBC uptake by T/B and tumor cells was mediated by Na+-dependent amino acid transporters (system ASC), whereas most [14C]Met transport in all cells was mediated by Na+-independent carriers (system L).Conclusions
The low anti-[18F]FACBC accumulation in granulocytes/macrophages may be advantageous in discriminating inflamed regions from tumors. The significant anti-[18F]FACBC uptake in T/B cells may cause false-positives in some cancer patients who undergo FACBC-positron emission tomography (PET). 相似文献45.
Kimitoshi Kato M.D. Tomoaki Watanabe Masahiko Itoh Shuntaro Yoshida Naohisa Hoshino Kazuro Itoh Fumiaki Sugimura Ariyoshi Iwasaki Yutaka Matsuo Hiroko Sawai Shigeyuki Imai Susumu Oshiba Atsuko Seki 《Journal of gastroenterology》1990,25(3):314-319
We investigated the role of the autonomic nervous system in gastric acid secretion, somatostatin concentration and PAS-positive
mucus production in Brunner’s glands in cysteamine-induced duodenal ulcer. Vagotomized rats were used. No ulcers occurred
in the groups with vagotomies of the hepatoduodenal, truncal or gastric branches after cysteamine administration. However,
in the hepatoduodenal branch vagotomized group, there was an increases in gastric acid secretion after cysteamine administration.
A similar increase was observed in the control group, but the decreases in somatostatin concentration and PAS-positive mucus
seen in the control group were not found in the hepatoduodenal vagotomized group. These results suggest that the hepatoduodenal
branch of the vagus nerve might play an important role in the ulcerogenic process of cysteamine-induced duodenal ulcer. 相似文献
46.
Lack of gene deletion for complement C4A deficiency in Japanese patients with systemic lupus erythematosus 总被引:5,自引:0,他引:5
H Yamada A Watanabe A Mimori K Nakano F Takeuchi K Matsuta K Tanimoto T Miyamoto Y Yukiyama K Tokunaga 《The Journal of rheumatology》1990,17(8):1054-1057
The frequency of C4A gene deletion was studied in Japanese patients with systemic lupus erythematosus (SLE) and was compared with healthy controls. DNA preparations were extracted from peripheral blood leukocytes from 59 patients with SLE and from 166 healthy persons, and digested by restriction enzymes. They were hybridized with C4 complementary DNA by the Southern blotting method and the deletion of C4A gene was judged from restriction fragment length polymorphism. At the same time phenotypic C4A deficiency (C4AQ0) was measured. Our results showed that the frequency of phenotypic C4A deficiency was 44.1% in Japanese patients with SLE and this value was comparable with that (43.2%) in Caucasian patients. On the other hand the deletion of C4A gene was not found in Japanese patients with SLE (0%), or in healthy controls (0.6%). Our results indicate that C4AQ0 may contribute to the pathogenesis of SLE beyond the ethnical differences but Japanese patients with SLE have a different genetic background from Caucasian patients with the C4A gene deleted. 相似文献
47.
M Matsuta T Akasaka S Kon Z Suzuki 《Nippon Hifuka Gakkai zasshi. The Japanese journal of dermatology》1989,99(5):601-607
A 5-year-old male considered clinically to have Ehlers-Danlos syndrome (EDS) type IV with main symptoms of fragility and easy bruisability of the skin was presented. Electron microscopic observations of collagen fibers and immunohistological examination of the localization of the type III collagen in the patient revealed dissimilarities in the size and the irregularities in the shape of collagen filaments, as well as a clear difference in localization of type III collagen when compared with normal skin of same age. 相似文献
48.
M. Matsuta M. Matsuta S. Kon C. Thompson P. E. LeBoit H.-U. Weier J. W. Gray 《Journal of cutaneous pathology》1994,21(1):1-6
This study shows that fluorescence in situ hybridization (FISH) to thin sections cut from paraffin-embedded material can lie used to distinguish between groups of melanocytic neoplasms and thus may be useful as an investigational and diagnostic tool. FISH with a probe for a repealed, alpha satellite sequence specific to chromosome 17 was used to investigate the chromosomal composition of dysplastic (or Clark's nevus) and Spitz's nevi and malignant melanomas. Hybridization was to thin (∼6 μm) sections cut from paraffin blocks. The number of signals per nucleus in normal diploid cells is expected to be less than 2 since the sections are thinner than one nuclear diameter. Keratinocytes and lymphocytes m these same sections showed 1–2 signals per nucleus with a mean of 1.2. Dysplastic nevi showed 1–4 hybridization signals per nucleus with a mean of 1.5. Spitz's nevi showed 1–2 signals per nucleus with a mean of 1.3. Melanomas showed 1–6 signals per nucleus with a mean of 2.1. We were thus able to use FISH to demonstrate differences in chromosome numbers between groups of benign and malignant melanocytic neoplasms. Technical improvements in the near future can be expected lo result in more precise estimates of chromosomal number. 相似文献
49.
Interleukin-23 and interleukin-27 exert quite different antitumor and vaccine effects on poorly immunogenic melanoma 总被引:7,自引:0,他引:7
Oniki S Nagai H Horikawa T Furukawa J Belladonna ML Yoshimoto T Hara I Nishigori C 《Cancer research》2006,66(12):6395-6404
Recent studies revealed that two novel interleukin (IL)-12-related cytokines, IL-23 and IL-27, have potent antitumor activities. However, the antitumor effects were mainly evaluated in relatively highly immunogenic tumors and have not been fully evaluated against nonimmunogenic or poorly immunogenic tumors. In this study, we investigated the antitumor efficacies of IL-23 and IL-27 on poorly immunogenic B16F10 melanoma and found that the antitumor responses mediated by IL-23 and IL-27 were clearly different. In syngeneic mice, mouse single-chain (sc) IL-23-transfected B16F10 (B16/IL-23) tumors exhibited almost the same growth curve as B16F10 parental tumor about until day 20 after tumor injection and then showed growth inhibition or even regression. In contrast, scIL-27-transfected B16F10 (B16/IL-27) tumors exhibited significant retardation of tumor growth from the early stage. In vivo depletion assay revealed that the antitumor effect of B16/IL-23 was mainly mediated by CD8+ T cells and IFN-gamma whereas that of B16/IL-27 mainly involved natural killer cells and was independent of IFN-gamma. We also found that antitumor effects of B16/IL-23 and B16/IL-27 were synergistically enhanced by treatment with IL-18 and IL-12, respectively. Furthermore, B16/IL-23-vaccinated mice developed protective immunity against parental B16F10 tumors but B16/IL-27-vaccinated mice did not. When combined with prior in vivo depletion of CD25+ T cells, 80% of B16/IL-23-vaccinated mice completely rejected subsequent tumor challenge. Finally, we showed that the systemic administration of neither IL-23 nor IL-27 induced such intense toxicity as IL-12. Our data support that IL-23 and IL-27 might play a role in future cytokine-based immunotherapy against poorly immunogenic tumors. 相似文献
50.
Obi S Yoshida H Toune R Unuma T Kanda M Sato S Tateishi R Teratani T Shiina S Omata M 《Cancer》2006,106(9):1990-1997
BACKGROUND: Hepatocellular carcinoma (HCC) with portal venous invasion (PVI) has a very poor prognosis, with a median survival of 3 months and virtually no survival at 1 year. The combination of intraarterial 5-fluorouracil (FU) and systemic interferon-alpha (IFNalpha) was recently reported to be effective against HCC with PVI, but these were small pilot studies. METHODS: One hundred and sixteen patients with HCC with PVI received IFNalpha (5,000,000 U intramuscularly on Days 1, 3, and 5 of each week of treatment) and 5-FU (500 mg into hepatic artery on Days 1-5 of the first and second week of each 4-week cycle). The therapy was either terminated at the end of the first cycle in cases with progressive disease, or continued for at least 3 cycles, when responses to treatment were evaluated by Eastern Cooperative Oncology Group criteria. The survival rate was compared with that of historical controls (n = 40). RESULTS: Nineteen (16%) patients showed complete response and another 42 (36%) showed partial response. Adverse events were limited to nausea and appetite loss. The survival rates at 12 and 24 months among overall patients were 34% and 18%, respectively, in contrast to 15% and 5% among the historical controls. Survival rates at 12 and 24 months were 81% and 59% among complete responders, respectively, and 43% and 18% among partial responders. CONCLUSION: The combination therapy with 5-FU and IFN was safe, and substantially improved the survival rate among the complete responders. These results provide a rationale for future randomized controlled trials. 相似文献