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61.
62.
Masaharu Muranaka Shuji Suzuki Kazuhiro Koizumi Hiroshi Igarashi Hiroshi Okumura Koyo Takeda Kenji Tadokoro Yoshihiko Horiuchi 《The Journal of allergy and clinical immunology》1978,62(5):276-282
All of the five commercially available benzylpenicillin preparations obtained from different sources and a PcG preparation prepared by filtration of a commercial PcG on Sephadex G10 elicited the systemic anaphylactic reactions in guinea pigs which had been immunized with benzylpenicilloyl (BPO)-Ascaris extract conjugate (BPO-As) mixed with aluminum hydroxide gel. These preparations could evoke no such reactions in guinea pigs immunized with BPO-bovine gamma globulin conjugate (BPO-BGG) emulsified with complete Freund's adjuvant. The severity of the systemic anaphylactic reactions correlated significantly with the titers of either 8-day passive cutaneous anaphylactic (8-day PCA) reactions or 4-hr PCA reactions evoked with the same benzylpenicillin preparations. In vitro benzylpenicillin preparation contracted the tracheas of the guinea pigs immunized with BPO-As. These results indicated that the commercially available benzylpenicillin preparations have enough antigenicity to evoke systemic anaphylactic reactions in guinea pigs immunized with BPO-As mixed with aluminum hydroxide gel. Such guinea pigs represent an animal model for investigation of penicillin allergy. 相似文献
63.
64.
Study of the biological activities of toxic shock syndrome toxin-1: II. Induction of the proliferative response and the interleukin 2 production by T cells from human peripheral blood mononuclear cells stimulated with the toxin 总被引:7,自引:1,他引:7 下载免费PDF全文
T. Uchiyama Y. Kamagata Xiao-Jie Yan Masako Kohno M. Yoshioka H. Fujikawa H. Igarashi M. Okubo F. Awano T. Saito-Taki M. Nakano 《Clinical and experimental immunology》1987,68(3):638-647
Toxic shock syndrome toxin-1 (TSST-1) is an exotoxin produced by Staphylococcus aureus isolated from patients with toxic shock syndrome. We investigated the proliferative response of human lymphocytes and their interleukin 2 (IL-2) production after stimulation with TSST-1 in vitro. Human cord blood mononuclear cells (HCBM) and human peripheral blood mononuclear cells (HPBM) could proliferate with TSST-1 stimulation. T cell-depleted HPBM showed only a marginal response to this toxin. A IL-2-like factor with a molecular weight of 15-18 kD was obtained from the supernatants of TSST-1-stimulated HPBM cultures. The factor was absorbed by CTLL-2 cells but not by T cell-depleted murine spleen cells, indicating that it is IL-2. HPBM are very sensitive to TSST-1: a low concentration of TSST-1 (0.01 ng/ml in 36 h stimulation) and a short period of stimulation (8 h at 10 ng/ml of the toxin) were fully effective for HPBM to produce substantial amounts of IL-2. Removal of T cells abrogated the TSST-1-induced IL-2 production by HPBM. Reconstituted cell cultures of nylon wool column-passed T cells and macrophages produced IL-2 by TSST-1 stimulation and, furthermore, the accessory activity of the macrophages could be partially replaced by a macrophage-derived factor containing interleukin 1. These findings indicate that T cells require macrophages or IL-1 for TSST-1-induced production of IL-2. The roles of lymphokines, including IL-2, in the development of this illness are discussed. 相似文献
65.
Frequent co-localization of Cox-2 and laminin-5 gamma2 chain at the invasive front of early-stage lung adenocarcinomas 总被引:7,自引:0,他引:7
Niki T Kohno T Iba S Moriya Y Takahashi Y Saito M Maeshima A Yamada T Matsuno Y Fukayama M Yokota J Hirohashi S 《The American journal of pathology》2002,160(3):1129-1141
Laminin-5 is an extracellular matrix protein that plays a key role in cell migration and tumor invasion. Cox-2 is an induced isoform of cyclooxygenases that plays an important role in carcinogenesis, suppression of apoptosis, angiogenesis, and metastasis of colon cancer. We report frequent co-expression of cox-2 and laminin-5 at the invasive front of early-stage lung adenocarcinomas. We investigated the expression of cox-2 and laminin-5 immunohistochemically in 102 cases of small-sized lung adenocarcinoma (maximum dimension, 2 cm or less). Cox-2 and laminin-5 were expressed in 97 (95.1%) and 82 (80.4%) cases, respectively. Both were preferentially localized in cancer cells at the cancer-stroma interface, although cox-2 tended to show a diffuse staining pattern in some cases. A comparison of their staining patterns revealed a striking similarity in their distribution in 24 cases, and a partial overlap between their localization in another 20 cases. Moreover, an overall correlation was found between the expression levels of cox-2 and laminin-5 (P = 0.018). To gain insight into the mechanisms that regulate the expression of these proteins, we additionally studied their expression in 58 cases of stage I lung adenocarcinoma, in which p53 status was determined by immunohistochemistry, polymerase chain reaction-single strand conformation polymorphism analysis, and direct sequencing. The results showed that tumors with mutant p53 tended to express more cox-2 than those with wild-type p53 (P = 0.080). Also, tumors that overexpressed p53 had higher levels of cox-2 and laminin-5 than those without p53 overexpression (P = 0.032 and 0.047, respectively). Further immunohistochemical analysis showed that tumors that overexpressed both epidermal growth factor receptor (EGFR) and erbB-2 had higher levels of cox-2 and laminin-5 than those without concomitant overexpression of these proteins (P = 0.014 and P = 0.018, respectively). To see whether EGFR signaling is involved in cox-2 and laminin-5 expression, we further conducted in vitro analyses using six lung adenocarcinoma cell lines (A549, HLC-1, ABC-1, LC-2/ad, VMRC-LCD, and L27). Western blot analyses showed that cox-2 mRNA levels, and to a lesser extent laminin-5 gamma2 mRNA levels, correlated with the expression levels of erbB-2 and the phosphorylated form of MAPK/ERK-1/2 protein. The addition of transforming growth factor-alpha increased both cox-2 and laminin-5 gamma2 mRNA levels in A549, ABC-1, and L27 with different kinetics; the induction of cox-2 occurred earlier than that of laminin-5 gamma2. Finally, the migration of ABC-1 cells was inhibited by MAP kinase kinase inhibitor PD98059 and a selective cox-2 inhibitor NS-398. In contrast, the migration of A549 cells was inhibited by PD98059, but much less effectively by NS-398. These results suggest that co-stimulatory mechanisms may exist that increase the expression of cox-2 and laminin-5 at the invasive front of lung adenocarcinomas and that EGFR signaling could be one of the mechanisms. Further investigations are warranted concerning the role of cox-2 and laminin-5 in cancer cell invasion and the significance of p53 and EGFR signaling in the regulation of cox-2 and laminin-5 expression. 相似文献
66.
D. Felmingham C. Feldman W. Hryniewicz K. Klugman S. Kohno D. E. Low C. Mendes A. C. Rodloff 《Clinical microbiology and infection》2002,8(S2):12-42
Bacterial resistance to antibiotics in community-acquired respiratory tract infections is a serious problem and is increasing in prevalence world-wide at an alarming rate. Streptococcus pneumoniae , one of the main organisms implicated in respiratory tract infections, has developed multiple resistance mechanisms to combat the effects of most commonly used classes of antibiotics, particularly the β -lactams (penicillin, aminopenicillins and cephalosporins) and macrolides. Furthermore, multidrug-resistant strains of S. pneumoniae have spread to all regions of the world, often via resistant genetic clones. A similar spread of resistance has been reported for other major respiratory tract pathogens, including Haemophilus influenzae , Moraxella catarrhalis and Streptococcus pyogenes . To develop and support resistance control strategies it is imperative to obtain accurate data on the prevalence, geographic distribution and antibiotic susceptibility of respiratory tract pathogens and how this relates to antibiotic prescribing patterns. In recent years, significant progress has been made in developing longitudinal national and international surveillance programs to monitor antibiotic resistance, such that the prevalence of resistance and underlying trends over time are now well documented for most parts of Europe, and many parts of Asia and the Americas. However, resistance surveillance data from parts of the developing world (regions of Central America, Africa, Asia and Central/Eastern Europe) remain poor. The quantity and quality of surveillance data is very heterogeneous; thus there is a clear need to standardize or validate the data collection, analysis and interpretative criteria used across studies. If disseminated effectively these data can be used to guide empiric antibiotic therapy, and to support—and monitor the impact of—interventions on antibiotic resistance. 相似文献
67.
Kazunori Nagai Yoshihiko Sugiyama Tsuyoshi Hosaka Hikoichiro Takaya 《Pathology international》1973,23(1):59-73
Five autopsy cases of thrombotic microangiopathy, including 3 cases associated with acute promyelocytic leukaemia, were examined macroscopically, light-and electronmicroscopically.
The so-called hyaline thrombi In thrombotic microangiopathy were composed of fibrin and its degenerative products. Thrombocytes and other blood cells were not seen in the thrombi.
At the site of the formation of a thrombus, there was no conspicuous change in the walls of the capillaries and arterioles. It was considered, therefore, that the intravascular deposition of fibrin was the primary event in the development of thrombotic microangiopathy.
In regard to the distribution and morphologic findings, there was no basic difference between the microthrombi in cases associated with acute promyelocytic leukaemia and those without it.
The bone marrow and some other organs in cases of thrombotic microangiopathy associated with acute promyelocytic leukaemia macroscopically revealed a green colour. Many thrombi composed of leukaemic cells and fibrin were found in the pulmonary arteries of these cases. Furthermore, prominent erythrophagocytosis in the bone marrow and lymph nodes was a common finding in these cases. 相似文献
The so-called hyaline thrombi In thrombotic microangiopathy were composed of fibrin and its degenerative products. Thrombocytes and other blood cells were not seen in the thrombi.
At the site of the formation of a thrombus, there was no conspicuous change in the walls of the capillaries and arterioles. It was considered, therefore, that the intravascular deposition of fibrin was the primary event in the development of thrombotic microangiopathy.
In regard to the distribution and morphologic findings, there was no basic difference between the microthrombi in cases associated with acute promyelocytic leukaemia and those without it.
The bone marrow and some other organs in cases of thrombotic microangiopathy associated with acute promyelocytic leukaemia macroscopically revealed a green colour. Many thrombi composed of leukaemic cells and fibrin were found in the pulmonary arteries of these cases. Furthermore, prominent erythrophagocytosis in the bone marrow and lymph nodes was a common finding in these cases. 相似文献
68.
69.
Hayashi M Ueda Y Yamaguchi T Sohma R Shibazaki M Ohkura T Inaba N 《American journal of reproductive immunology (New York, N.Y. : 1989)》2005,53(3):113-119
PROBLEM: Tumor necrosis factor-alpha (TNF-alpha) is present in human placental and uterine cells at the early and late stages of gestation and promotes the regulation of trophoblast growth and invasion. We evaluated whether TNF-alpha levels in the placenta and blood of pre-eclamptic women differed from those with normal pregnancies. METHOD OF STUDY: The subjects were 39 pregnant women carrying single fetuses (21 normal-pregnant and 18 pre-eclamptic patients). Their average gestational age at entry was 38-39 weeks. Peripheral blood was collected before the onset of labor and separated serum was stored at -20 degrees C. A tissue segment of the placenta was cut and frozen in liquid nitrogen immediately after delivery at -80 degrees C. The frozen placental tissue was added to phosphate-buffered saline. The tissue was fully homogenized and centrifuged. Separated supernatant was stored at -80 degrees C. TNF-alpha levels in separated serum and TNF-alpha and total protein (TP) levels in separated supernatant were measured. The presence of TNF-alpha in the placenta was evaluated by immunohistochemistry in five pre-eclamptic and five normal-pregnant patients. RESULTS: Serum TNF-alpha levels were higher in pre-eclampsia than in normal pregnancies. However, TNF-alpha/TP levels in the placenta did not differ significantly between the two groups. As for TNF-alpha immunostaining of trophoblastic cells in the placenta, it was weak in three and moderate in two of the normal pregnancies, while it was absent in two, weak in one, and moderate in two in the pre-eclampsia group. CONCLUSIONS: We demonstrated no significant increase in TNF-alpha/TP levels in the placenta in pre-eclampsia despite a significant increase in serum TNF-alpha levels. There was no strong immunostaining for TNF-alpha detected by immunohistochemistry in the pre-eclampsia group. These findings suggest that TNF-alpha in the placenta is not a key cytokine to interfere with normal trophoblast invasion into the myometrium in pre-eclampsia, and that sources other than the placenta may contribute to the elevated levels of TNF-alpha found in the circulation of pre-eclamptic patients. 相似文献
70.
Fujii K Miyashita T Omata T Kobayashi K Takanashi J Kouchi K Yamada M Kohno Y 《American journal of medical genetics. Part A》2003,(1):65-68
We present the case of a 14-year-old Japanese girl who had both Gorlin syndrome and ulcerative colitis. She had complained of blood stools for 6 months and severe scoliosis from her infancy. Physical examination revealed multiple nevi, palmar and plantar pits, jaw cysts, and calcification of the falx cerebri, leading to the diagnosis of Gorlin syndrome. Total colonoscopy revealed an edematous and spotty bleeding mucosa extending from the anus to the transverse colon. Histological examination was also compatible with ulcerative colitis. Thus, we diagnosed her as having Gorlin syndrome with ulcerative colitis. Gene analysis revealed a mutation, 1247InsT, in the human patched gene (PTCH), resulting in the truncation of PTCH protein. Since Gorlin syndrome and ulcerative colitis are rare disorders in childhood, this association is interesting, suggesting a correlation between the hedgehog signaling and intestinal disorders. 相似文献