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81.
Doi A Okano M Akagi H Nishizaki K Taguchi T Murakami T Ohtsuka A 《Anatomical science international / Japanese Association of Anatomists》2003,78(1):62-67
The musk shrew, Suncus murinus, is one of the primitive mammals and has a pair of palatine tonsils. In the present study,
we investigated the blood microvascular architecture of the tonsil in this animal by scanning electron microscopy of corrosion
casts. The paranodular arterioles entered the lymph nodule to form a coarse capillary plexus within the nodule. Some of the
arterioles reached the dome region to give rise to a fine meshwork of dome subepithelial capillaries. This dome subepithelial
capillary network did not show any hairpin or switch-back patterns, as seen in human and rabbit tonsils. Both of the nodular
and dome capillaries were drained into the postcapillary venules in the periphery of the nodular or the paranodular region.
On the surface of these cast venules, oval-shaped indentations were seen corresponding to the luminal surface of the high
endothelial venules. These venules were collected into the large vein at the bottom of the tonsil. The blood vascular architecture
of the musk shrew tonsil is basically the same as those of other mucosa-associated lymphoid tissues in mammals. 相似文献
82.
Masayuki Ishihara PhD Kiyohaya Obara MD Singo Nakamura PhD Masanori Fujita MD PhD Kazunori Masuoka MD Yasuhiro Kanatani MD PhD Bonpei Takase MD PhD Hidemi Hattori PhD Yuji Morimoto MD PhD Miya Ishihara PhD Tadaaki Maehara MD PhD Makoto Kikuchi PhD 《Journal of artificial organs》2006,9(1):8-16
An aqueous solution of photocrosslinkable chitosan containing azide groups and lactose moieties (Az-CH-LA) incorporating paclitaxel
formed an insoluble hydrogel within 30 s of ultraviolet light (UV) irradiation. The chitosan hydrogel showed strong potential
for use as a new tissue adhesive in surgical applications and wound dressing. The fibroblast growth factor (FGF)-2 molecules
retained in the chitosan hydrogel and in an injectable chitosan/IO4-heparin hydrogel remain biologically active, and were gradually released from the hydrogels as they biodegraded in vivo.
The controlled release of biologically active FGF-2 molecules from the hydrogels caused induction of angiogenesis and collateral
circulation occurred in healing-impaired diabetic (db/db) mice and in the ischemic limbs of rats. Paclitaxel, which is an antitumor reagent, was also retained in the chitosan hydrogel
and remained biologically active as it was released on degradation of the hydrogel in vivo. The chitosan hydrogels incorporating
paclitaxel effectively inhibited tumor growth and angiogenesis in mice. The purpose of this review is to describe the effectiveness
of chitosan hydrogel as a local drug delivery carrier for agents (e.g., FGF-2 and paclitaxel) to control angiogenesis. It
is thus proposed that chitosan hydrogel may be a promising new local carrier for drugs such as FGF-2 and paclitaxel to control
vascularization. 相似文献
83.
Culture of chondrocytes in fibroin-hydrogel sponge 总被引:5,自引:0,他引:5
Aoki H Tomita N Morita Y Hattori K Harada Y Sonobe M Wakitani S Tamada Y 《Bio-medical materials and engineering》2003,13(4):309-316
Fibroin-hydrogel sponge and collagen gel were used as scaffold for in vitro cartilage regeneration. Fibroin-hydrogel sponge was formed by phase separation from freezed fibroin solution. Chondrocytes were harvested from proximal humerus, distal femur and proximal tibia of 4-week-old Japanese white rabbits and inoculated in the fibroin-hydrogel sponge and collagen gel. Those constructs were cultured in DMEM supplemented with 10% FCS and 50 ml L-ascorbate at 37 degrees C. Histological observation, measurement of sulfated glycosaminoglycan and cell density were carried out at 3, 7, and 14 days after the cultivation. Well-defined cartilage tissue can be seen both in the fibroin-hydrogel sponge and in the collagen gel. The matrix was intensely stained by safranin-O and showed a metachromatic reaction in both group. However, the quantity of sulfated glycosaminoglycan and cell density of the fibroin-hydrogel sponge group were increased more rapidly than these of the collagen gel group. Thus, the chondrocytes proliferated in the fibroin sponge without losing their differentiated phenotype. It is possible that culture environment in the fibroin sponge was suitable for chondrocytes regeneration. 相似文献
84.
Nishimura Hiroyuki; Hattori Susumu; Ueda Genjiro; Abe Masaaki; Yang Kwangseok; Nozawa Shingo; Okamoto Hiroshi; Zhang Danqing; Tsurui Hiromichi; Hirose Sachiko; Shirai Toshikazu 《International immunology》1995,7(7):1115-1123
Using two mAb, one specific to the alternative exon 6-dependentepitope of CD45 molecules(JH6.2) and one a natural thymocytotoxicautoantibody (NTA) with an unknown reactive epitope (NTA260),we subdivided splenic CD4+ T cells from 2-month-old BALB/c miceinto five phenotypically distinct subsets. CD45RC+NTA260–(SI) cells were phenotypically analogous to CD4+ T cells predominatingin newborn mice and produced a significant amount of IL-2, butnot so IL-4, IL-10 or IFN- when stimulated with immobilizedanti-CD3 mAb in vitro. They appeared to consist mainly of naiveThP cells. The CD45RC+;NTA260+ (S II) subset also produced IL-2,but not other cytokines; however, the IL-2 levels produced weremuch higher than seen with the S I subset, thereby suggestingthe predominance of further maturated ThP cells. The D45RC–NTA260+(S III) subset mainly produced IL-4, IL-10, IFN- and less IL-2,and contained memory cells that helped the secondary antibodyresponse to a recall antigen, and hence contained Th2 and probablya mixture of Th0 and Th1 cells. The CD45RC–NTA260–(S IV) subset was a poor responder to the immobilized anti-CD3mAb. The CD45RCbrightNTA260dull(S V) subset consisted of a smallnumber of cells that were phenotypically analogous to activatedCD4+ T cells. While an age-associated decrease in the proportionof S I and less markedly in S II and in turn increase in S IIIsubsets of CD4+ T cells occurred in normal BALB/c mice, autoimmunedisease-prone (NZBxNZW)F1 mice showed a marked age-associateddecrease in the proportion of not only S I, II but also IIIsubsets. As aged (NZBxNZW)F1 mice carry CD4+ T helper cellsfor IgG anti-DNA antibody production, such age-associated polarizationto the S IV subset appears to be critical in the pathogeneslsof autoimmune disease in these mice. 相似文献
85.
Shinichiro Nanko Akira Ueki Mineko Hattori Xiao Y. Dai Tsukasa Sasaki Rimmei Fukuda Kazuhiko Ikeda Hajime Kazamatsuri 《American journal of medical genetics. Part A》1994,54(4):361-364
Parkinson's disease is thought to be caused by a combination of unknown environmental, genetic, and degenerative factors. Evidence from necropsy brain samples and pharmacokinetics suggests involvement of dopamine receptors in the pathogenesis or pathophysiology of Parkinson's disease. Genetic association studies between Parkinson's disease and dopamine D2, D3 and D4 receptor gene polymorphisms were conducted. The polymorphism was examined in 71 patients with Parkinson's disease and 90 controls. There were no significant differences between two groups in allele frequencies at the D2, D3, and D4 dopamine receptor loci. Our findings do not support the hypothesis that susceptibility to Parkinson's disease is associated with the dopamine receptor polymorphisms examined. © 1994 Wiley-Liss, Inc. 相似文献
86.
Watanabe M Goto N Watanabe Y Nishiguchi S Shimada K Yasunga T Yamanishi H 《International journal of molecular medicine》2005,15(4):561-566
Interleukin-18 (IL-18) is one of the pivotal cytokines controlling the defense mechanism called inflammation. As a first step to develop proteins for controlling the IL-18 level, we initiated a study of IL-18-binding proteins (IL-18BPs). Twenty-four IL-18BP family members, 11 from vertebrates and 13 from chordopoxviruses, were picked from the NCBI database. Eight of these vertebrate IL-18BPs and two of the chordopoxvirus IL18-BPs were identified here and characterized as new members of the IL-18BP family. Their IL-18 binding domains were aligned and the distribution of highly conserved critical amino acid residues was analyzed and used to construct a phylogenetic tree. From this tree it was inferred that at least two independent events created two different ancestral viral IL-18BP genes by retroposition of IL-18BP genes from the vertebrate lineage. These two events are estimated to have occurred after an ancient mammalian IL-18BP gene diverged from birds, and before the mammalian IL-18BP gene diverged into human, ungulate and rodent IL-18BP genes. Moreover, our results suggest that IL-18BP and interleukin-1 receptor, type II (IL-1R2) had a common ancestral gene and diverged from the ancestral gene into IL-18BP and IL-1R2 genes in the fish period. 相似文献
87.
Hattori S Sakuma K Wakutani Y Wada K Shimoda M Urakami K Kowa H Nakashima K 《Neuroscience letters》2004,368(3):319-322
Early onset familial Alzheimer's disease with spastic paraparesis (FAD-SP) has been associated with mutations of the presenilin 1 gene (PSEN1). We report a pedigree of FAD-SP due to a novel missense mutation of PSEN1 (Y154N). The symptoms of the proband were characterized by presenile dementia in her 40s, preceded by spastic paraparesis in her 30s, whereas the mother of the proband presented with spastic paraparesis in her 40s, followed by symptoms of dementia in her mid 60s. The mutation was found only in the proband, and not in a normal family member, normal Japanese control subjects, patients with sporadic Alzheimer's disease or patients with familial spastic paraparesis without dementia. Thus, Y154N is a novel PSEN1 mutation responsible for FAD-SP of Japanese origin. 相似文献
88.
Hajime Kuhara Kazunori Ikei Takashi Wakabayashi Hidemasa Kishimoto 《Pathology international》1986,36(7):1083-1088
A 58-year-old man with liposarcoma originating from the right paratesticular area was reported. Histologically, liposarcoma showed a well-differentiated sclerosing type. Coexistence of transitional cell carcinoma of the urinary bladder and liposarcoma was also revealed. The cases of paratesticular liposarcoma in the literature are briefly reviewed. 相似文献
89.
Yu Nakamura Masatoshi Takeda Hideo Suzuki Hideyuki Hattori Kunitoshi Tada Shiro Hariguchi Shigeo Hashimoto Tsuyoshi Nishimura 《Neuroscience letters》1991,130(2):195-198
Formalin-fixed paraffin-embedded hippocampal sections of brains with early-onset and late-onset Alzheimer's disease were studied immunohistochemically with antisera against cathepsin D and cathepsin B. In addition to the staining of neuronal perikarya, some of the senile plaques visualized by Bielshowsky silver staining and some of reactive astrocytes were positively stained with the antisera against cathepsin D and cathepsin B in brains with Alzheimer's disease. Abnormal localization of cathepsin D and cathepsin B immunoreactivity in neuronal perikarya was observed in brains with early-onset Alzheimer's disease. These findings demonstrate that the distribution of lysosomal proteases was altered in brains with Alzheimer's disease, suggesting the primary and/or secondary involvement of the lysosomal proteases in the pathological process of Alzheimer's disease. 相似文献