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排序方式: 共有8081条查询结果,搜索用时 15 毫秒
81.
Nahoko Kawamura Makoto Tomita Midori Hasegawa Kazutaka Murakami Kunihiro Nabeshima Hiroko Kushimoto Masami Kasugai Kazuo Takahashi Yoshiyuki Hiki Tsuneo Kinukawa Nobumitsu Usuda Satoshi Sugiyama 《Clinical transplantation》2005,19(S14):27-31
Abstract: The effects of antibody-mediated rejection on long-term graft survival have not been fully investigated. The aim of this study is to clarify the influence on long-term survival of deposition of the complement split product C4d in allografts using polyclonal anti-C4d antibody. Inclusion criteria were recipients who underwent graft biopsy during acute deterioration of graft function within the first 2 yr after transplantation. Patients whose graft did not survive more than 1 yr and who received graft from an human leucocyte antigen (HLA)-identical sibling or an ABO-incompatible donor were excluded. Among the 92 recipients investigated, 22 (23.9%) had peritubular capillary C4d deposition, 15 (16.3%) had glomerular capillary C4d deposition and seven (7.6%) had both peritubular and glomerular capillary C4d deposition. Twenty of these 22 patients revealed acute cellular rejection, including borderline changes. There was no significant relationship between pathological severity of acute rejection and presence or absence of peritubular capillary C4d deposition. Graft survival was inferior in patients with peritubular capillary C4d deposition to that in patients without C4d deposition (p = 0.0419). Graft survival in patients with glomerular C4d deposition did not differ from that in patients without C4d deposition. In conclusion, C4d deposition in peritubular capillaries has a substantial impact on long-term graft survival. 相似文献
82.
Masahiro Takahashi Toshihide Mizoguchi Shunsuke Uehara Yuko Nakamichi Shuhua Yang Hiroko Naramoto Teruhito Yamashita Yasuhiro Kobayashi Minoru Yamaoka Kiyofumi Furusawa Nobuyuki Udagawa Takashi Uematsu Naoyuki Takahashi 《Journal of bone and mineral metabolism》2009,27(1):24-35
Osteoclasts are formed from the monocyte-macrophage lineage in response to receptor activator of nuclear factor κB ligand
(RANKL) expressed by osteoblasts. Bone is the most common site of breast cancer metastasis, and osteoclasts play roles in
the metastasis. The taxane-derived compounds paclitaxel and docetaxel are used for the treatment of malignant diseases, including
breast cancer. Here we explored the effects of docetaxel on osteoclastic bone resorption in mouse culture systems. Osteoclasts
were formed within 6 days in cocultures of osteoblasts and bone marrow cells treated with 1,25-dihydroxyvitamin D3 plus prostaglandin E2. Docetaxel at 10−8 M inhibited osteoclast formation in the coculture when added for the entire culture period or for the first 3 days. Docetaxel,
even at 10−6 M added for the final 3 days, failed to inhibit osteoclast formation. Osteoprotegerin, a decoy receptor of RANKL, completely
inhibited osteoclast formation when added for the final 3 days. Docetaxel at 10−8 M inhibited the proliferation of osteoblasts and bone marrow cells. RANKL mRNA expression induced by 1,25-dihydroxyvitamin
D3 plus prostaglandin E2 in osteoblasts was not affected by docetaxel even at 10−6 M. Docetaxel at 10−6 M, but not at 10−8 M, inhibited pit-forming activity of osteoclasts cultured on dentine. Actin ring formation and l-glutamate secretion by osteoclasts were also inhibited by docetaxel at 10−6 M. Thus, docetaxel inhibits bone resorption in two different manners: inhibition of osteoclast formation at 10−8 M and of osteoclast function at 10−6 M. These results suggest that taxanes have beneficial effects in the treatment of bone metastatic cancers.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
83.
84.
Maruyama K Iijima K Ikeda M Kitamura A Tsukaguchi H Yoshiya K Hoshii S Wada N Uemura O Satomura K Honda M Yoshikawa N 《Pediatric nephrology (Berlin, Germany)》2003,18(5):412-416
Podocin is an integral membrane protein encoded by NPHS2, which is mapped to 1q25-31 and is exclusively expressed in glomerular podocytes. NPHS2 mutations are responsible for autosomal recessive familial steroid-resistant nephrotic syndrome (SRNS) with minor glomerular abnormalities or focal segmental glomerulosclerosis (FSGS), which is characterized by early childhood onset (age less than 6 years) and rapid progression to chronic renal insufficiency. This gene mutation is also responsible for an adolescent/adult onset form of autosomal recessive familial FSGS with heavy proteinuria. It has been demonstrated that sporadic SRNS and heavy proteinuria are also due to NPHS2 gene mutations. We isolated genomic DNA from 36 Japanese children with chronic renal insufficiency caused by SRNS or heavy proteinuria, and analyzed all eight exons and exon-intron boundaries of NPHS2 using the polymerase chain reaction and direct sequencing. The age at onset of disease was 3.9+/-0.5 years. There were 29 patients with SRNS and 7 with heavy proteinuria without nephrotic syndrome at the onset, but all patients developed chronic renal insufficiency 4.6+/-0.8 years after the onset. A new homozygous missense variant of NPHS2, G34E (G101A) in exon 1, was detected in 1 of 36 patients. However, this homozygous variant was also found in 1 of 44 normal controls, suggesting that the mutation is a polymorphism. Two silent variants (T954C and A1038G) in exon 8 of this gene were also identified in some of the patients and normal controls, indicating that the silent variants are also polymorphisms. There was no significant difference in the genotypic and allelic frequencies of T954C and A1038G polymorphisms between the patients and normal controls. In conclusion, NPHS2 gene mutations are not a major cause of chronic renal insufficiency caused by sporadic SRNS or heavy proteinuria in Japanese children. 相似文献
85.
Purpose. The study was done to determine the characteristics and prevalence of myocardial ischemia with inverted T waves after noncardiac
surgery.
Methods. A list of patients who developed electrocardiogram (ECG) T-wave inversion associated with wall-motion abnormalities observed
by transthoracic echocardiography (TTE) following noncardiac surgery was generated from the intensive care unit (ICU) medical
records database between January 1, 1995, and December 31, 2000. The hospital records of these patients were analyzed retrospectively.
Results. Among 4219 patients (2187 men and 2032 women) who were admitted to the ICU after noncardiac surgery, 13 developed myocardial
ischemia with inverted T waves postoperatively. All of the patients were middle-aged or elderly women with no history of coronary
artery disease; nine of them had undergone intraabdominal surgery. Characteristic ECG findings included inverted T waves in
the left precordial leads, which subsequently became prominent with QT prolongation. In all of these patients, wall-motion
abnormalities were observed on the anterior wall, but these resolved within 60 days of the episode. Myocardial ischemia was
asymptomatic, with neither hemodynamic changes nor adverse cardiac events.
Conclusion. Newly developed giant negative T waves with QT prolongation in the ECG may indicate myocardial stunning, but do not in themselves
imply a poor prognosis. The marked preponderance of middle-aged and elderly women with this type of myocardial ischemia remains
to be explained.
Received: June 7, 2002 / Accepted: December 20, 2002
Address correspondence to: Y. Esaki 相似文献
86.
The dose-related effects of ketamine on mortality and cytokine responses to endotoxin-induced shock in rats 总被引:6,自引:0,他引:6
Taniguchi T Takemoto Y Kanakura H Kidani Y Yamamoto K 《Anesthesia and analgesia》2003,97(6):1769-1772
In our previous study, ketamine administration was found to inhibit hypotension, metabolic acidosis, and cytokine responses in endotoxemia. However, only a few studies have indicated whether ketamine has the dose-related beneficial effects after endotoxin injection. Our objective was to clarify the dose-related effects of ketamine on mortality and cytokine responses to endotoxemia in rats. Sixty-five rats were divided at random among five equal groups: Group C was given saline alone. Group E was given endotoxin alone (Escherichia coli endotoxin; 10 mg/kg, IV). Group L received a a low dose of ketamine (5 mg.kg(-1).h(-1), IV), Group M a medium dose of ketamine (10 mg.kg(-1).h(-1), IV), and Group H a high dose of ketamine (20 mg.kg(-1).h(-1), IV), all exposure to endotoxin. After endotoxin injection, hemodynamics, acid-base status, mortality rate, and plasma concentrations of tumor necrosis factor alpha and interleukin 6 were assessed for each of the five groups. Endotoxin injection produced progressive hypotension, metabolic acidosis, and a large increase in plasma cytokine concentrations. Mortality rates 8 h after endotoxin injection were 0% for group C, 92% for group E, 48% for group L, 0% for group M, and 32% for group H. Ketamine administration thus clearly had a beneficial effect on mortality rates, with that for group M lower than for groups L and H (P < 0.05). The cytokine responses to endotoxin were somewhat suppressed in group M but not in group L. Ketamine administration dose-independently inhibited hypotension, metabolic acidosis, and cytokine responses in rats injected with endotoxin. 相似文献
87.
Tetsuya Sakai Tadasuke Use Hiroko Shimamoto Taku Fukano Koji Sumikawa 《Journal canadien d'anesthésie》2003,50(10):1027-1030
PURPOSE: To determine the optimal dose of intrathecal morphine that produces satisfactory analgesia with minimum side effects in elderly patients undergoing transurethral resection of the prostate (TURP). METHODS: In this double-blind prospective study, 42 patients undergoing TURP with spinal anesthesia were allocated to one of three groups. Group A (n = 14) received tetracaine, 10 mg, alone. Group B (n = 13) and Group C (n = 15) received morphine 0.05 mg and 0.10 mg, respectively, in combination with tetracaine. Postoperative pain, nausea and pruritus were evaluated using visual analogue scales (VAS). SpO(2) and respiratory rate were also assessed. RESULTS: At three, five, seven and 24 hr after spinal anesthesia, the VAS scores for pain in Groups B and C were significantly less than in Group A. Group C experienced significantly greater VAS scores for pruritus as compared to Groups A and B. There was no significant difference in the intensity of nausea among the three groups. No patient experienced hypoxemia (SpO(2) < 90%) and respiratory depression (respiratory rate < 10 beats*min(-1)) in any group. CONCLUSION: A dose of 0.05 mg in intrathecal morphine with spinal anesthesia would be optimal for elderly patients undergoing TURP. 相似文献
88.
Hiroko Kunitake Richard Hodin Paul C. Shellito Bruce E. Sands Joshua Korzenik Liliana Bordeianou 《Journal of gastrointestinal surgery》2008,12(10):1730-1737
Purpose The impact of infliximab (IFX) on postoperative complications in surgical patients with Crohn’s disease (CD) and ulcerative
colitis (UC) is unclear. We examined a large patient cohort to clarify whether a relationship exists between IFX and postoperative
complications.
Methods A total of 413 consecutive patients—188 (45.5%) with suspected CD, 156 (37.8%) with UC, and 69 (16.7%) with indeterminate
colitis—underwent abdominal surgery at the Massachusetts General Hospital between January 1993 and June 2007. One hundred
one (24.5%) had received preoperative IFX ≤ 12 weeks before surgery. These patients were compared to those who did not receive
IFX with respect to demographics, comorbidities, presence of preoperative infections, steroid use, and nutritional status.
We then compared the cumulative rate of complications for each group, which included deaths, anastomotic leak, infection,
thrombotic complications, prolonged ileus/small bowel obstruction, cardiac, and hepatorenal complications. Potential risk
factors for infectious complications including preexisting infection, pathological diagnosis, and steroid or IFX exposure
were further evaluated using logistic regression analysis.
Results Patients were similar with respect to gender (IFX = 40.6% men vs. non-IFX = 51.9%, p = 0.06), age (36.1 years vs.37.8, p = 0.43), Charlson Comorbidity Index (5.3 vs. 5.7, p = 0.25), concomitant steroids (75.3% vs. 76.9%, p = 0.79), preoperative albumin level (3.3 vs. 3.2, p = 0.36), and rate of emergent surgery (3.0% vs. 3.5%, p = 1.00). IFX patients had higher rates of CD (56.4% vs. 41.9%, p = 0.02), concomitant azathioprine/6-mercaptopurine use (34.6% vs. 16.6%, p < 0.0001), and lower rates of intra-abdominal abscess (3.9% vs. 11%, p < 0.05). After surgery, the two groups had similar rates of death (2% vs. 0.3% p = 0.09), anastomotic leak (3.0% vs. 2.9%, p = 0.97), cumulative infections (5.97% vs. 10.1%, p = 1), thrombotic complications (3.6% vs. 3.0%, p = 0.06), prolonged ileus/small bowel obstructions (3.9 vs. 2.8, p = 0.59), cardiac complications (1% vs. 0.6%, p = 0.42), and hepatic or renal complications (1.0 vs. 0.6% p = 0.72). A logistic regression model was then created to assess the impact of IFX, as well as other potential risk factors,
on the rates of cumulative postoperative infections. We found that steroids (odds ratio [OR] = 1.2, p = 0.74), IFX (OR 2.5, p = 0.14), preoperative diagnosis of CD (OR = 0.7, p = 0.63) or UC (OR = 0.6, p = 0.48), and preoperative infection (OR = 1.2, p = 0.76) did not affect rates of clinically important postoperative infections.
Conclusions Preoperative IFX was not associated with an increased rate of cumulative postoperative complications.
Dr. Sands has received research grants and honoraria for lecturing and consulting from Centocor. 相似文献
89.
Kitamura H Torigoe T Asanuma H Honma I Sato N Tsukamoto T 《The Journal of urology》2007,178(2):692-696
PURPOSE: HLA class I down-regulation in cancer cells confers immunological escape from cytotoxic T lymphocytes. We assessed the frequency of down-regulation of HLA class I antigens in a large series of prostate cancer tissues and determined the mechanism of up-regulation by investigating prostate cancer cell lines. MATERIALS AND METHODS: Immunohistochemical staining for HLA class I was done in specimens of 419 prostate cancers. We also investigated clinicopathological parameters, and the relationships between HLA class I down-regulation and the parameters. Furthermore, we examined whether HLA down-regulation was caused by epigenetic changes in vitro. RESULTS: HLA class I was down-regulated in 311 prostate cancers (74.2%) and it significantly correlated with beta2-microglobulin down-regulation and a higher clinical stage. Flow cytometric analysis revealed a low level of HLA class I in LNCaP cells, which was up-regulated by the histone deacetylase inhibitor trichostatin A (Sigma). Trichostatin A up-regulated LNCaP beta2-microglobulin at the protein level. Furthermore, chromatin immunoprecipitation assay using an anti-acetylated histone H3 antibody provided direct evidence that trichostatin A up-regulated beta2-microglobulin by modulating the acetylation status of the promoter region in LNCaP cells. CONCLUSIONS: The current study shows that the prevalence of HLA class I down-regulation is high in prostate cancer but histone deacetylase inhibitors can up-regulate HLA class I in LNCaP cells by up-regulating beta2-microglobulin. We suggest that the combination of an immunotherapeutic approach and histone deacetylase inhibition would accentuate the effects of current immunotherapies for prostate cancer. 相似文献
90.
Hang Zhao Takeshi Sugawara Shihiro Miura Tetsuya Iijima Satoshi Kashimoto 《Journal canadien d'anesthésie》2007,54(3):201-207
PURPOSE: The purpose of this study was to determine if intrathecal landiolol, a beta1-blocker, can modulate formalin-induced nociception and spinal c-Fos expression in mice, in the absence of anesthesia. METHODS: Thirty-two mice were randomly assigned to one of four groups: the control group (n = 8) received intrathecal normal saline 10 microL, while the other three groups (n = 8 for each) received intrathecal landiolol at escalating doses of 250 microg.kg(-1), 500 microg.kg(-1) and 750 microg.kg(-1) respectively, immediately after induction of anesthesia with isoflurane. After awakening, inflammatory pain was induced by 10 microL of 5% formalin solution injected into the dorsal surface of the right hind paw. The nociceptive behaviours including licking, biting and lifting of the injected paw were cumulatively recorded as seconds of behaviours/min during phase I (0-10 min) and phase II (10-45 min). The c-Fos protein expressions in the spinal dorsal horn were detected with immunohistochemical techniques in the control and landiolol 750 microg.kg(-1) groups. RESULTS: Compared to the control group, intrathecal injection of landiolol 750 microg.kg(-1) significantly decreased pain-related behaviours in phase I, while intrathecal landiolol 250 microg.kg(-1), 500 microg.kg(-1) and 750 microg.kg(-1) significantly decreased pain-related behaviours in phase II during the formalin test. The numbers of c-Fos immunoreactive nuclei in the L5 spinal dorsal horn were significantly lower in the landiolol 750 microg.kg(-1) group compared to the control group (landiolol 750 microg.kg(-1) 2.4 +/- 1.1 vs control 9.2 +/- 3.9; P < 0.01). CONCLUSION: The present study indicates that intrathecally administered landiolol produces significant antinociceptive effects in the formalin test. Although further studies exploring the detailed mechanism are needed, these data suggest a potential role of beta1-adrenoreceptors in spinal nociceptive processing. 相似文献