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991.
The purpose of this study was to evaluate the expressions and the roles of proteins involved in cell cycle regulation and DNA repair in cis-diamminedichloroplatinum (II) (cisplatin or CDDP)-induced acute renal failure (ARF). Treatment with CDDP (6 mg/kg, iv) induced tubular damage and increased serum creatinine (Scr) and the number of TUNEL-positive cells in the outer stripe of the outer medulla in rats, which reached peak levels at 5 days after CDDP. The expressions of cyclin-dependent kinase inhibitors (p21 and p27), cyclin B1, cyclin D1, PCNA, GADD 45, and GADD 153 were significantly increased in the outer medulla, reaching peak levels at 3 days after CDDP. Increments of p27 and PCNA were observed in the same nuclei. Sodium arsenite (SA), a heavy metal, attenuated tubular damage and increased Scr- and TUNEL-positive cells at 5 days after CDDP. SA augmented CDDP-induced increment of p27 but suppressed the increased expression of cyclin B1 and cyclin D1 at 3 days after CDDP. SA-induced attenuation of nephrotoxicity was associated with enhanced expression of proliferating cell nuclear antigen (PCNA) and growth-arrest and DNA damage (GADD) 153 in damaged tubular cells. Our findings indicated that (1) proteins related to cell cycle regulation and DNA repair are induced in CDDP nephrotoxicity, (2) the SA-induced attenuation of CDDP nephrotoxicity is associated with increased expression of p27 and decreased expression of cyclin B1 and cyclin D1, they all induce cell cycle arrest at G1/S and G2/M, and (3) enhanced expression of DNA repair-related proteins is also associated with attenuation of CDDP-nephrotoxicity.  相似文献   
992.
The SH2 domain-containing protein-tyrosine phosphatase PTPN11 (Shp2) is required for normal development and is an essential component of signaling pathways initiated by growth factors, cytokines, and extracellular matrix. In many of these pathways, Shp2 acts upstream of Ras. About 50% of patients with Noonan syndrome have germ-line PTPN11 gain of function mutations. Associations between Noonan syndrome and an increased risk of some malignancies, notably leukemia and neuroblastoma, have been reported, and recent data indicate that somatic PTPN11 mutations occur in children with sporadic juvenile myelomonocytic leukemia, myelodysplasic syndrome, B-cell acute lymphoblastic leukemia, and acute myelogenous leukemia (AML). Juvenile myelomonocytic leukemia patients without PTPN11 mutations have either homozygotic NF-1 deletion or activating RAS mutations. Given the role of Shp2 in Ras activation and the frequent mutation of RAS in human tumors, these data raise the possibility that PTPN11 mutations play a broader role in cancer. We asked whether PTPN11 mutations occur in other malignancies in which activating RAS mutations occur at low but significant frequency. Sequencing of PTPN11 from 13 different human neoplasms including breast, lung, gastric, and neuroblastoma tumors and adult AML and acute lymphoblastic leukemia revealed 11 missense mutations. Five are known mutations predicted to result in an activated form of Shp2, whereas six are new mutations. Biochemical analysis confirmed that several of the new mutations result in increased Shp2 activity. Our data demonstrate that mutations in PTPN11 occur at low frequency in several human cancers, especially neuroblastoma and AML, and suggest that Shp2 may be a novel target for antineoplastic therapy.  相似文献   
993.
Autologous tumor cells stimulated with T lymphocytes (AuTL) were generated ex vivo from peripheral blood lymphocytes over a two-week co-culturing process with autologous tumor cells. These AuTLs were capable of lysing established tumor cell lines and may have a potential for efficacy as an adoptive immunotherapy (IT) in advanced and metastatic refractory cancer patients (pts). We investigated the feasibility of a combination of AuTL transfer and chemotherapy (ChT) based on the conventional conditioning regimen in order to take advantage by both the anticancer effects and reconstruction of antitumor immunity. Nineteen patients were enrolled in a pilot clinical trial. The two administrations of AuTL were given prior to chemotherapy (ChT) for one treatment cycle. The treatment was repeated at least for three cycles over a one-week interval. The conventional ChT regimen was based on the standard dosage. The pts consisted of 3 of gastric cancer, colon cancer, lung adenocarcinoma, respectively, 6 of esophageal cancer, and 2 of breast and pancreas carcinoma, respectively. AuTLs were administered 1x/2 weeks using direct injection or intraarterial infusion. The median duration of the treatment was over 11.5 months, and the median survival time was 14.8 months. Adverse events related to both the ChT and AuTL transfers at all dosages were minimal. Four of the 13 pts achieved major tumor responses (2 CR: complete regression and 2 PR: partial regression) in this study. Three pts showed progressive disease, and 6 pts had stable disease for over 90 days. PBMC were evaluated for cytokine production prior to the treatment and after 3 treatments. Two and one of 4 CR/PR pts had increased IFN-gamma and TNF-alpha production with no TGF-beta1 responses by their PBMC after 3 treatments, respectively. Two out of 6 pts who experienced stable disease after the treatment had high IFN-gamma and TNF-alpha responses and no TGF-beta1 or IL-4 response. TGF-beta1 and IL-4 secretion increased in parallel in 3 out of 3 pts that experienced progressive disease after the treatment. These data show that combination therapy of AuTL transfer and non-myeloablative ChT is a feasible option for patients with refractory advanced cancers without serious adverse events and without reducing Th1 cytokine responses in peripheral blood for most of the pts that responded to the treatment. According to each mechanism of IT and ChT, a more stringent evaluation of AuTL transfer combined with non-myeloablative ChT for various kinds of cancers should be performed to manage the immunodeficiency in the pts with advanced cancer and to improve the effect of antitumor AuTLs.  相似文献   
994.
A 62-year-old woman was admitted because of epigastralgia and tarry stool. An endoscopic examination revealed type 3 cancer in the lower body of the stomach, and abdominal CT scan demonstrated enlarged abdominal paraaortic lymph nodes. The preoperative diagnosis was cStage IV gastric cancer (cT3, cN3, cH0, cP0, cM0). Since a curative operation was deemed impossible, we started neoadjuvant chemotherapy using TS1 plus cisplatin (CDDP) for downstaging. TS-1 (100 mg/day) was orally administered for 3 weeks, and CDDP (90 mg/body) was administered intravenously on day 8. Appetite loss of grade 3 and leucopenia of grade 1 were observed. After two courses of chemotherapy, the primary lesion was reduced in size, and the paraaortic lymph nodes disappeared on abdominal CT scan. The serum tumor marker became normal. Subsequently, she underwent curative total gastrectomy with splenectomy and lymph node dissection. Histological examination of the primary lesion revealed marked fibrosis and a small amount of residual cancer cells. The histological changes by neoadjuvant chemotherapy were judged to be grade 2 for the main tumor. It is suggested that neoadjuvant chemotherapy using TS-1 plus CDDP is effective for advanced gastric cancer with massive lymph node metastases.  相似文献   
995.
Ten cases of advanced and metastatic colorectal cancer treated with irinotecan plus fluorouracil and l-leucovorin systemic chemotherapy (CPT-11/5-FU/l-LV) were investigated. The 10 patients consisted of 7 males and 3 females with a mean age of 64.3 years. We diagnosed adenocarcinoma of the colon in 2 patients and of the rectum in 8 patients. Five patients had liver and lung metastases, 1 had lymph node metastases, 1 had bone marrow metastases and 3 had recurrence in a pelvic lesion. All patients underwent 3-week chemotherapy regimen (CPT-11 50 mg/m2/week + 5-FU 400 mg/m2/week + l-LV 20 mg/m2/week). Five patients received this regimen as a first-line chemotherapy and the other patients as a second-line chemotherapy after 5-FU/l-LV chemotherapy. The effect was CR or PR in all patients receiving the regimen as a first-line chemotherapy. The progression free survival time was 6.8 months and mean survival time was 10.0 months in the first-line patients. Otherwise, all second-line patients had PD. The suppression of white blood cells (grade 1 or 2) was seen in 4 patients. All patients were able to receive the systemic chemotherapy in the outpatient setting. CPT-11/5-FU/l-LV chemotherapy appears to be an effective first-line chemotherapy for advanced and metastatic colorectal cancer.  相似文献   
996.
The patient was a 58-year-old man who suffered from non-resectable gastric cancer, staged intraoperatively for peritoneal dissemination and paraaorta lymph node metastasis at another hospital in December 2002. He was initially treated with TS-1 as an outpatient. However, he was readmitted on March 4, 2003 for hematuria, general fatigue, jaundice and dyspnea. He was diagnosed with gastric cancer duodenum invasion, obstructive jaundice and lymphangitis carcinomatosa, and began weekly TXL as second-line chemotherapy on March 26. TXL (70 mg/ m2) was infused once a week for 3 weeks followed by a 1-week interval as one cycle. One week after the first infusion therapy, the jaundice and dyspnea were greatly improved. CT scan showed the lymphangitis carcinomatosa had disappeared and paraaorta lymph node metastasis was reduced to 60% after one cycle of the treatment. The toxic events were leukopenia (grade 1) and alopecia (grade 1).  相似文献   
997.
BACKGROUND: To evaluate the role of 18F-Fluorodeoxyglucose positron emission tomography (FDG-PET), spot images were added to whole-body FDG-PET images in a patient with suspected lymph node recurrence of breast cancer. METHODS: FDG-PET spot images were obtained of 44 patients who had undergone surgical resection of breast cancer as were whole-body FDG-PET images. A total of 33 lesions in 19 patients (mean age, 59 years; range, 39-70 years) were diagnosed as lymph node recurrence clinically, and standardized uptake values (SUVs) were calculated for whole body images and spot images. Lesions were also scored from 1 (not clear) to 3 (very clear) for both the whole body and spot images. RESULTS: For mediastinal lymph node metastases, the SUVs of the spot images (SUVsp) (mean, 4.0; range, 2.1-6.6) were significantly higher than the SUVs of the whole body images (SUVwb) (mean, 3.3; range, 2.1-5.8). For other lymph node metastases (neck, axilla, etc.), there was no significant difference between SUVwb (2.6; 1.4-6.5) and SUVsp (2.8; 1.6-8.1). CONCLUSIONS: By adding spot images, the evaluation of lymph node metastases became easier. Adding spot images to whole-body FDG-PET may be useful.  相似文献   
998.
PURPOSE: To determine the ratio of fetal lung volume (FLV) to fetal body weight (FBW) by using ultrasonography (US) and magnetic resonance (MR) imaging and to evaluate the usefulness of this ratio in predicting pulmonary hypoplasia (PH) in fetuses at high risk. MATERIALS AND METHODS: MR imaging lung volumetry and US biometry were performed in 90 fetuses at 25-39 weeks gestation. In the control group of 73 fetuses, normal lung development was confirmed at neonatal follow-up and the normative ratio of MR imaging-measured FLV to US-estimated FBW (FLV/FBW) was determined. The high-risk group included 17 fetuses at risk for PH. The FLV/FBW was compared between the control and high-risk groups and with US parameters for predicting the development of PH in the high-risk group. Measurements 2 or more standard deviations below the mean control group measurement were considered abnormal. Comparisons of the FLV/FBW between groups were made by using the Student t test. The association between development of PH and measurement of each parameter was analyzed by using the Fisher exact probability test. RESULTS: In the control group, the FLV/FBW decreased with gestational age during the third trimester and had a normal distribution (mean ratio, 0.028 mL/g; range, 0.015-0.444 mL/g). The mean FLV/FBW for the nine fetuses with PH (0.012 mL/g +/- 0.008) was significantly lower (P <.001) than that for the control group (0.028 mL/g +/- 0.007). Fetuses with abnormal FLV/FBW values were at significantly greater risk (P <.05) for PH development. Abnormal FLV/FBW values had higher diagnostic accuracy than abnormal US parameters. Sensitivity of the FLV/FBW was 89% (eight of nine fetuses); specificity, 88% (seven of eight fetuses); positive predictive value, 89% (eight of nine fetuses); negative predictive value, 88% (seven of eight fetuses); and accuracy, 88% (15 of 17 fetuses). CONCLUSION: The FLV/FBW reflects the adequacy of intrauterine lung growth and can help predict PH.  相似文献   
999.
Serum Interleukin-12 Levels in Patients with Gastric Cancer   总被引:1,自引:0,他引:1  
Purpose To evaluate the immunological status of patients with gastric cancer before surgery, we investigated the relationship between serum interleukin-12 (IL-12) levels and clinicopathological factors.Methods We measured serum IL-12 levels in 127 patients with gastric cancer and 35 healthy controls, by a sandwich enzyme-linked immunosorbent assay using the Human IL-12 +p40 Immunoassay kit.Results The serum IL-12 levels in the patients with gastric cancer were significantly higher than those of the healthy controls (P < 0.05). There were no significant differences in disease stage or gross appearance among the cancer groups, but the serum IL-12 levels in patients with T4 disease were significantly lower than those in patients with T1, T2, or T3 (P < 0.01). There were no significant differences in serum IL-12 levels between patients with and those without lymph node, liver, or peritoneal metastasis. The serum IL-12 levels in patients with distant metastasis were significantly lower than those in patients without distant metastasis (P < 0.02). There were no significant differences in the serum IL-12 levels according to classification by histopathological findings. Analysis with the linear correlation coefficient showed no significant correlation between serum IL-12 and serum carcinoembryonic antigen, carbohydrate antigen (CA) 19-9, CA 72-4, -fetoprotein, or immunosuppressive acidic protein. However, there was a significant relationship between serum IL-12 levels and soluble IL-2 receptor levels (r = 0.53, P < 0.01).Conclusion Serum IL-12 levels in patients with far-advanced gastric cancer were significantly lower than those in patients with less-advanced gastric cancer. This is because macrophages in patients with far-advanced cancer would be hectic and unable to produce sufficient IL-12.  相似文献   
1000.
Purpose. The purpose of the current study was to evaluate the molecular mobility of amorphous indomethacin and salicin in the relaxed glassy state based on spin-lattice relaxation times (T1c) and to clarify the effects of molecular mobility on their physical stability.Methods. Pulverized glassy amorphous indomethacin and salicin samples were completely relaxed, and the T1c values were investigated using solid-state 13C-nuclear magnetic resonance (NMR) at temperatures below the glass transition temperature (Tg). All NMR spectra were obtained using the T1c measurement method combined with variable-amplitude cross-polarization, the Torchia method, and total sideband suppression method.Results. The T1c value of amorphous indomethacin indicated that 73% of carbons were in a state of monodispersive relaxation, suggesting that the amorphous state was relatively homogeneous and restricted, particularly in backbone carbons. On the other hand, 92% of carbons of amorphous salicin exhibited both fast and slow biphasic relaxation. Individual structures of the salicin molecules behaved heterogeneously, and thus the entire molecule showed relatively fast local as well as slow mobility.Conclusions. At temperatures below Tg, amorphous salicin had relatively greater molecular mobility than amorphous indomethacin. This difference in the molecular mobility of the two compounds is correlated with their crystallization behavior. Solid-state 13C NMR provides valuable information on the physical stability of amorphous pharmaceuticals.  相似文献   
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