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71.
TZUHUA LIN JUKKA PAJARINEN YUSUKE KOHNO MASAHIRO MARUYAMA MONICA ROMERO-LOPEZ JHIH-FONG HUANG KARTHIK NATHAN TAHSIN N. KHAN ZHENYU YAO STUART B. GOODMAN 《Cytotherapy》2018,20(8):1028-1036
Background
Mesenchymal stromal cell (MSC)–based therapy has great potential to modulate chronic inflammation and enhance tissue regeneration. Crosstalk between MSC-lineage cells and polarized macrophages is critical for bone formation and remodeling in inflammatory bone diseases. However, the translational application of this interaction is limited by the short-term viability of MSCs after cell transplantation.Methods
Three types of genetically modified (GM) MSCs were created: (1) luciferase-expressing reporter MSCs; (2) MSCs that secrete interleukin (IL)-4 either constitutively; and (3) MSCs that secrete IL-4 as a response to nuclear factor kappa-light-chain-enhancer of activated B cell (NFκB) activation. Cells were injected into the murine distal femoral bone marrow cavity. MSC viability and bone formation were examined in vivo. Cytokine secretion was determined in a femoral explant organ culture model.Results
The reporter MSCs survived up to 4 weeks post-implantation. No difference in the number of viable cells was found between high (2.5?×?106) and low (0.5?×?106) cell-injected groups. Injection of 2.5?×?106 reporter MSCs increased local bone mineral density at 4 weeks post-implantation. Injection of 0.5?×?106 constitutive IL-4 or NFκB-sensing IL-4–secreting MSCs increased bone mineral density at 2 weeks post-implantation. In the femoral explant organ culture model, LPS treatment induced IL-4 secretion in the NFκB-sensing IL-4–secreting MSC group and IL-10 secretion in all the femur samples. No significant differences in tumor necrosis factor (TNF)α and IL-1β secretion were observed between the MSC-transplanted and control groups in the explant culture.Discussion
Transplanted GM MSCs demonstrated prolonged cell viability when transplanted to a compatible niche within the bone marrow cavity. GM IL-4–secreting MSCs may have great potential to enhance bone regeneration in disorders associated with chronic inflammation. 相似文献72.
Properties of Invertases in Sugar Storage Tissues of Citrus Fruit and Changes in Their Activities during Maturation 总被引:4,自引:0,他引:4
Both acid and alkaline invertases were present in immature juice sacs of satsuma mandarin (Citrus‘Unshu Marcovitch”) fruit, in which sugar content was low. Maturing and mature juice sacs, in which sugar content increased steadily with time, were characterized by the presence of alkaline invertase and the absence of acid invertase. When the immature juice sacs were homogenized with 0.2 M sodium phosphate-citrate buffer (pH 8.0), almost all of the acid invertase activity was found in the solubilized fraction, whereas almost all of the alkaline invertase activity was present in the insoluble fraction. The distribution of alkaline invertase between the solubilized and insoluble fractions changed with the development of fruit. The acid invertase had a molecular weight of 69,000, optimum pH of 4.8–5.3, and Km value for sucrose of 7.3 mM. The alkaline invertase had a molecular weight of 200,000, pH optimum of 7.2–7.7, and Km value of 35.7 mM. The hydrolysing activities of both enzymes for raffinose were considerably less than those for sucrose. The alkaline invertase had lower activity for raffinose than the acid invertase. 相似文献
73.
Eggs of Pseudocentrotus depressus were activated artificially by Loeb's "double treatment method". 50 min after activation, a number of asters were produced in the eggs. It was confirmed by electron microscopy that centrioles with a typical fine structure were present in artificially induced asters.
An unfertilized egg of Hemicentrotus pulcherrimus was divided into 2 halves, nucleated and non-nucleated, by centrifugation on a sucrose bed. Each half was activated by the same method as mentioned above. Several asters were produced in both halves after a certain period of incubation. The presence of bodies considered to be centrioles were demonstrated in the asters in both nucleated and non-nucleated halves.
The results add probability to the view that the centrioles are produced de novo in artificially activated eggs and fragments. 相似文献
An unfertilized egg of Hemicentrotus pulcherrimus was divided into 2 halves, nucleated and non-nucleated, by centrifugation on a sucrose bed. Each half was activated by the same method as mentioned above. Several asters were produced in both halves after a certain period of incubation. The presence of bodies considered to be centrioles were demonstrated in the asters in both nucleated and non-nucleated halves.
The results add probability to the view that the centrioles are produced de novo in artificially activated eggs and fragments. 相似文献
74.
Comparative Study on the Ability of Various Teratocarcinomas to Form Chimeric Mouse Embryos 总被引:1,自引:1,他引:0
KAZUNORI HANAOKA YOSHIHIRO KATO TAKEHIKO NOGUCHI 《Development, growth & differentiation》1986,28(3):223-231
Various embryonal carcinoma cells of different origins were compared as to the ability to form chimeric blastocysts by means of aggregating with normal 8-cell stage mouse embryos. The teratocarcinoma lines examined were OTT6050 and five newly established ones including a spontaneous testicular teratocarcinoma STT-2. The present results have revealed that distinct differences existed in the ability of colonizing blastocysts among teratocarcinomas and also among embryonal carcinoma cell lines.
Since STT-2 stem cells were found to be incorporated into blastocysts most efficiently, further development of the blastocysts were examined in utero. It was found that STT-2 stem cells could be incorporated into the fetuses up to the 7-to 28-somite stages. This is the first case to demonstrate that testicular teratocarcinoma cells with the male germ cell origin have the developmental potency to participate into mouse embryogenesis. 相似文献
Since STT-2 stem cells were found to be incorporated into blastocysts most efficiently, further development of the blastocysts were examined in utero. It was found that STT-2 stem cells could be incorporated into the fetuses up to the 7-to 28-somite stages. This is the first case to demonstrate that testicular teratocarcinoma cells with the male germ cell origin have the developmental potency to participate into mouse embryogenesis. 相似文献
75.
YOSHIOMI KATO 《Development, growth & differentiation》1973,15(3):193-199
When larval tissue is exposed to a hormonal milieu lacking juvenile hormone, adult characters appear directly, omitting the pupal stage, in some insects but not in others, including Bombyx mori. An attempt was made to induce omission of pupal characters in this species by varying the stage of the larval epidermis to be tested. Pieces of larval integument taken from fourth- and fifth-instar larvae of various stages were transplanted to developing adults. Although the number of cuticle layers and the types of cuticle produced differed depending on the age of the donors, none of the pieces omitted secreting the pupal cuticle. It is concluded that the larval epidermis cannot omit secreting pupal cuticle, and that a transition of tissue competence may play an important part in the sequential appearance of larval, pupal, and adult characters. 相似文献
76.
KIYOKO YAMAZAKI-YAMAMOTO KENZO TAKATA YOSHIHIRO KATO 《Development, growth & differentiation》1984,26(3):295-302
The length of chromosomes in the presumptive ectoderms of Cynops embryos was measured at nine successive cell divisions from the 6th (cleavage stage) to the 14th (gastrula stage). Up to the 10th cell division (cleavage stage) the chromosome length remained constant. At the 11th cell division the chromosomes began to shorten and continued to shorten at every cell division up to the 14th cell division. The degree of shortening and the mode of variation in length corresponded to the respective developmental stages of cleavage, blastula and gastrula. During those periods when chromosomes became shortened, some fine C-bands of the paracentromeric region found in earlier stages fused together. The chromatin of interphase nuclei also showed considerable changes during chromosome shortening. Besides the size reduction of interphase nuclei, the number of C-band granules in an interphase nucleus decreased in parallel with chromosome shortening and fusion of C-bands in mitotic chromosome. 相似文献
77.
Nitrogen assimilation in citrus trees 总被引:1,自引:0,他引:1
TADASHI KATO 《Physiologia plantarum》1980,48(3):416-420
Assimilation of 15N-ammonium and 15N-nitrate was examined in 3-year-old satsuma mandarin (Citrus unshiu Marcovitch) trees. Experiments were designed to establish the time course of incorporation of nitrogen just taken up into amino compounds. In fine roots, absorbed 15N-ammonium was actively incorporated into glutamine and then into glutamic acid and asparagine. When feeding 15N-nitrate, glutamic acid and asparagine were actively synthesized, but glutamine synthesis was comparatively low as compared with that in ammonium feeding. In current leaves and fruits, a clear difference in the labelling patterns of amino acids was found between the ammonium and nitrate feedings. The amino acid most markedly labelled was asparagine in the ammonium feeding and glutamine in the nitrate feeding. Considering the most heavily labelled component in leaves and fruits, the main form of the nitrogen components transported upward in the xylem was discussed. 相似文献
78.
79.
80.
Two subspecies of the papilionid butterfly Byasa alcinous , B. a. bradanus and B. a. alcinous , have varying degrees of larval aggregation. Early instar larvae of ssp. bradanus always occur in aggregations. To determine the functions of larval aggregation in this subspecies, we examined the effects of leaf toughness on larval performance when caterpillars were reared alone and in aggregations. Newly hatched larvae were reared either individually or in groups of 10 and were fed either tough or tender leaves of Aristolochia debilis . When fed tough leaves, more gregarious larvae survived the first instar. This difference between solitary and aggregated larvae did not occur when caterpillars were fed soft leaves. The effects of aggregation on larval weight and duration were not significant between leaf-toughness treatments. Larval aggregation of B. a. bradanus improves larval survivorship in early instars that use host plants with tough leaves. 相似文献