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171.
Tomita Y Uchida T Zhang QW Shimizu I Iwai T Yoshikawa M Kishihara K Nomoto K Yasui H 《Surgery today》2000,30(9):816-820
The results of previous studies indicate that only CD4+ T cells generated via the indirect pathway play an essential role in causing discordant skin xenograft rejection. The present
study was conducted in an attempt to clarify further the roles of effector T cells generated via direct pathways on discordant
xenograft rejection using CD45 exon-6 knockout (CD45−/−; C57BL/6 (B6): H-2b) mice. It has been strongly suggested that CD45 exon-6 knockout mice have profound impairment in T-cell functions via an
indirect pathway. When human skin was grafted onto untreated normal C57BL/6 (B6; H-2b) mice, rejection occurred within 12 days; however, in the CD45 exon-6 knockout mice, the grafts lasted for slightly longer
as in fully allogeneic C3H (H-2k) skin rejection, with a mean survival time ± SD of 19.4 ± 1.5 days and median survival times of 19 days. The difference in
survival periods between the human and C3H skin grafts in the CD45 knockout mice was not statistically significant. Both CD4+ and CD8+ T cells seemed activated in the spleens of these CD45 exon-6 knockout mice 10 days after the human skin grafting. These results
suggest that effector T cells generated via a direct pathway can cause discordant skin xenograft rejection, and that CD45
exon-6 knockout mice can generate effector T cells via a direct pathway to reject discordant skin xenografts, similarly to
fully allogeneic skin allografts.
Received: June 24, 1999 / Accepted: May 30, 2000 相似文献
172.
(Received for publication on Jan. 5, 1999; accepted on Sept. 17, 1999) 相似文献
173.
OBJECTIVE: To determine the possible use of the mammalian acrosomal marker vehicle-associated membrane protein (VAMP)/synaptobrevin to detect acrosome abnormalities in human sperm. DESIGN: Analysis of human sperm after fixation and staining with an anti-VAMP antibody. SETTING: An academic research institution. PATIENT(S): Semen samples from consenting patients who were participating in an infertility treatment program. INTERVENTION(S): Human sperm samples were fixed, permeabilized with detergent, and examined by immunocytochemistry. MAIN OUTCOME MEASURE: Immunostaining. RESULT(S): Observation of sperm from patients with no obvious sperm morphological defects revealed normal looking acrosomes, as assessed by VAMP immunostaining. However, severe acrosome malformations were detected in other cases. The observations registered varied from the absence of a fully formed organelle in samples of patients with globozoospermia to abnormal VAMP staining in samples from patients with acrosomal defects. CONCLUSION: VAMP/synaptobrevin may be a useful marker for the functional assessment of acrosomal status in human sperm. 相似文献
174.
The evaluation of meconium disease by distribution of cathepsin D in intestinal ganglion cells 总被引:8,自引:0,他引:8
Tatekawa Y Kanehiro H Kanokogi H Nakajima Y Nishijima E Muraji T Imai Y Tsugawa C Toyosaka A Nakano H 《Pediatric surgery international》2000,16(1-2):53-55
Meconium disease (MD) results in intestinal obstruction in the neonate where tenacious meconium is found in the distal ileum
and proximal colon. The obstructive symptoms improve at several days of age after some of the meconium is passed. We observed
premature infants with MD who underwent ileostomy for intestinal obstruction due to tenacious meconium. Afterward, meconium
was passed well and the clinical symptoms improved. After closing the ileostomy, growth and defecation became normal. The
MD in our cases was documented by histologic changes in the maturation of ganglion cells observed at the time of ileostomy
creation and closure. For an objective evaluation of the maturation of intestinal ganglion cells (IGC), we attempted to distinguish
immature from mature cells by the expression of cathepsin D. We examined the distribution of cathepsin D in IGC in patients
with MD to test the hypothesis that ganglion-cell immaturity might be related to MD. In ganglion cells at the time of ileostomy,
cathepsin D was detected in the perinuclear cytoplasm (immature staining pattern), while at the time of ileostomy closure
it was detected in intense granules throughout the cytoplasm (mature staining pattern). We propose that it would be possible
to evaluate the maturation of IGC by the intracellular distribution of cathepsin D in MD and suggest that immaturity of IGC
might be the cause of MD.
Accepted: 28 June 1999 相似文献
175.
Yasushi Ohki Yukihiro Yoshizawa Masayuki Watanabe Makoto Kuwashima Akihiro Morikawa 《Pediatrics international》2008,50(5):636-639
Background: To determine institutional policies concerning percutaneously inserted central venous catheter (PICC) utilization and also frequencies of complications such as pericardial effusion (PCE), cardiac tamponade (CT), pleural effusion, ascites, venous thrombosis, and catheter removal difficulties. Methods: Nationwide postal questionnaire survey was carried out that included institutional policies on PICC and numbers of complications recorded from January 1999 to December 2003. Results: A total of 98 replies were received from 193 neonatal intensive care units (NICU) in Japan. As a catheter tip location, positions outside of the heart were highly preferred, while only 9% accepted a right atrial position. Twenty‐eight cases of PCE or CT were reported, representing an estimated frequency of 0.07–0.11% of PICC insertions. Pleural effusion/ascites and removal difficulties (36 and 35 cases, respectively) were encountered in approximately 0.09–0.14% of insertions. Conclusions: Frequency of PCE/CT appeared comparable to previously reported occurrences. Also, pleural effusion/ascites and removal difficulty appeared to be rare complications. 相似文献
176.
Akihiro Nawa Fumitaka Kikkawa Michiyasu Kawai Hisao Mano Setsuko Goto Nobuhiko Suganuma Yutaka Tomoda Yukihiro Nishiyama Nobuo Nakashima 《International journal of cancer. Journal international du cancer》1993,53(6):932-937
To determine the prognostic significance of human papilloma virus (HPV) DNA in histologically normal lymph nodes, we developed a nested polymerase chain-reaction (PCR) method on HPV16, 18 and 33 DNAs for formalin-fixed, paraffin-embedded tissues. We investigated 370 histologically normal lymph nodes from 15 patients treated for stage-IB/IIB (FIGO) invasive cervical cancer. HPV16 DNA was detected in 7 (47%) and HPV18 DNA in 3 (20%) of the cervical cancers. Examination of histologically normal lymph nodes from these 10 patients by nested PCR revealed HPV DNA in 5 (50%) of them; in all cases HPV type in lymph nodes and tumor was the same. Two of these 5 patients had a recurrence (pelvic cavity or lung) and died of cancer, although all 5 had had pelvic radiotherapy after radical hysterectomy and lymphadenectomy. These findings indicate that nested PCR is useful for evaluating early lymph-node involvement retrospectively in HPV-positive cases. 相似文献
177.
Anxiolytic-Like Effects of Perospirone, a Novel Serotonin-2 and Dopamine-2 Antagonist (SDA)-Type Antipsychotic Agent 总被引:1,自引:0,他引:1
Hideki Sakamoto Kenji Matsumoto Yukihiro Ohno Mitsutaka Nakamura 《Pharmacology, biochemistry, and behavior》1998,60(4):873-878
We examined the anxiolytic potential of perospirone, a novel serotonin-2 and dopamine-2 antagonist (SDA)-type antipsychotic agent, and compared its effects with those of the standard anxiolytic diazepam and the conventional antipsychotic haloperidol by using conditioned defensive burying (CDB) and social interaction (SI) tests in rats. The tests were conducted 1 h after oral administration of the drug. Diazepam inhibited CDB specifically directed toward a probe previously associated with brief electric shock and increased the time spent in SI by pairs of naive rats in a brightly illuminated novel environment. Perospirone mimicked the effects of diazepam by dose dependently suppressing CDB and facilitating SI. In contrast, haloperidol failed to inhibit CDB or increase SI. Thses results suggested that, unlike the conventional antipsychotic haloperidol, perospirone exerts anxiolytic-like effects in animal models with different motivational and emotional states. A braoder efficacy of perospirone for the treatment of anxiety and related symptoms in schizophrenia is discussed. 相似文献
178.
Effects of glycyrrhizin on immune-mediated cytotoxicity 总被引:10,自引:0,他引:10
MASAHIDE YOSHIKAWA YUJI MATSUI HIROSHI KAWAMOTO NORIE UMEMOTO KAZUMI OKU MASAKI KOIZUMI JUNICHI YAMAO SHIGEKI KURIYAMA HIROSHI NAKANO NOBUMICHI HOZUMI SHIGEAKI ISHIZAKA HIROSHI FUKUI 《Journal of gastroenterology and hepatology》1997,12(3):243-248
Intravenous administration of glycyrrhizin is known to decrease elevated plasma transaminase levels in patients with chronic viral hepatitis, in which immune-mediated cytotoxicity by cytotoxic T lymphocytes and tumour necrosis factor (TNF)-α is considered to play an important pathogenic role. However, the immunological interpretation of the transaminase-lowering action of glycyrrhizin is not known. Studies were performed to elucidate this action immunologically by assessing the effects of glycyrrhizin on immune-mediated cytotoxicity using an antigen-specific murine CD4+ T hybridoma line, which exhibits cytotoxicity against antigen-presenting cells after stimulation with specific antigen, and a murine TNF-α-sensitive fibroblast line. Glycyrrhizin inhibited the cytotoxic activity of the T cells against antigen-presenting cells and also suppressed TNF-α-induced cytotoxicity in the TNF-α-sensitive cell line in vitro. These results suggest that the decrease of elevated transaminase levels by glycyrrhizin in patients with chronic viral hepatitis is mediated in part by inhibition of immune-mediated cytotoxicity against hepatocytes. 相似文献
179.
180.
Nakagawa Y Iinuma M Matsuura N Yi K Naoi M Nakayama T Nozawa Y Akao Y 《Journal of pharmacological sciences》2005,97(2):242-252
Six main sesquiterpene lactones (germacranolides) from Calea urticifolia were evaluated for in vitro cytotoxicity against human tumor cell lines HL60 and SW480 cells. Among them, arucanolide and parthenolide displayed marked cytotoxicity against both cell lines. Arucanolide exhibited a low IC(50) in HL60 cells. The cytotoxic activity of arucanolide was observed at lower concentrations compared to that of parthenolide, which has been reported to be a typical and simple germacranolide. The activity was found to be mainly due to apoptosis that was assessed by morphological findings, DNA ladder formation (24 - 36 h), and flow cytometric analysis in HL60 cells. Western blotting and an apoptosis inhibition assay using caspase inhibitors did not demonstrate the activation of any caspases tested. However, the mitochondrial membrane potential of HL60 cells was lost after 24-h treatment with arucanolide, and concurrently apoptosis-inducing factor (AIF) released from mitochondria was detected by Western blot analysis. The inactivation of nuclear factor-kappaB, which has been commonly shown in parthenolide-induced apoptosis, did not occur in arucanolide-induced apoptosis. Taken together, the findings presented here indicate that arucanolide induced marked apoptosis in HL60 cells mainly by dissipating mitochondrial membrane potential, which would trigger AIF-induced apoptosis. 相似文献