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91.
Ilgan S Yang DJ Higuchi T Zareneyrizi F Kim EE Podoloff DA 《Cancer biotherapy & radiopharmaceuticals》1998,13(3):177-184
It is known that membrane folic acid receptors are responsible for cellular accumulation of folate and folate analogs, such as methotrexate, and overexpressed on various tumor cells. This study was aimed to develop an 111In labelled DTPA-methotrexate (DTPA-MTX) to image tumor folate receptors in vivo. DTPA-MTX was synthesized by reacting ethylenediamine with MTX. The resulting amino analogue of MTX was reacted with DTPA dianhydride in basic aqueous solution followed by dialysis. Tissue distribution was determined in breast tumor-bearing rats at 0.5, 2, 24, and 48 h (n = 3/time interval). To determine receptor-mediated process 111In-DTPA-MTX was co-administrated with varying blocking doses of cold folate to tumor-bearing rats. Planar imaging and whole-body autoradiograms were performed. The data was compared to that using 111In-DTPA. In animal studies, tumor/blood count density ratios at 0.5-48 h gradually increased from 0.8 +/- 0.32 to 2.2 +/- 0.41 with 111In-DTPA-MTX. Conversely, these values showed time-dependent decrease from 1.19 +/- 0.69 to 0.56 +/- 0.10 with 111In-DTPA in the same time period. Tumor/muscle and tumor/blood count density ratios significantly decreased with high doses of folic acid co-administration. Planar images and autoradiograms confirmed that the tumors could be visualized acceptably with 111In-DTPA-MTX. The results indicate the feasibility of using 111In-DTPA-MTX to image tumors through a folate receptor-mediated process. 相似文献
92.
To determine the availability and limitations of the detection of ischemic lesions by stress thallium-201 myocardial SPECT as the daily routine procedure, we compared and evaluated the detectability of the quantitative analysis (%uptake and washout rate (WR)) and visual evaluation in 104 patients with effort angina and 17 normal subjects. Visual evaluation combined with WR analysis resulted in significantly higher sensitivity (88.0%) but lower specificity (60.2%) than the other methods. The sensitivity by visual evaluation was quite low in multivessel disease (MVD), and in the regions supplied by mild coronary stenosis or by the left circumflex artery. These were markedly improved by combining visual evaluation and WR analysis, but sensitivity in the MVD group was unsatisfactory even with this analytic method in comparison with the single vessel disease group. One of the causes of low sensitivity in the MVD group might be the "true negative": No induction of the ischemia in the regions of milder stenosis, or the regions supplied by the collateral coronary flow. We therefore conclude that the combination of visual evaluation as a qualitative analysis and WR analysis as a quantitative analysis, is the most useful daily routine procedure as a screening test for detecting ischemia. 相似文献
93.
Association analysis of the GABA(A) receptor subunit genes cluster on 5q33-34 and alcohol dependence in a Japanese population 总被引:4,自引:0,他引:4
Recent investigations suggest that genetic susceptibility to alcohol dependence may be conferred by GABA(A) receptor subunit genes. In this study, three RFLPs at the GABA(A)beta2, GABAAalpha6, GABA(A)alpha1 and two at the GABA(A)gamma2 receptor subunit genes, were examined for association with alcohol dependence in 189 subjects meeting DSM-III-R criteria for this disorder and 152 unrelated controls from a Japanese population. The results demonstrated no association between the AlwNI RFLP at the GABA(A)alpha6 receptor subunit gene and alcohol dependence (P = 0.059). However, the NciI RFLP at the GABA(A)gamma2 receptor subunit gene was associated with alcohol dependence comorbid with antisocial personality disorder (P = 0.021). This supports a recent finding reporting an association between the GABA(A)gamma2 receptor subunit gene and alcohol dependence with criminal record in a Finnish population. Taking into account the effects of multiple comparisons, this result should be interpreted with caution pending replication. 相似文献
94.
Kouichirou Nishiyama Hajime Hirose Yoshiaki Iguchi Kazuhiro Yamamoto Takashi Masaki Takahiro Kamijo Takeshi Ino Jun Yamanaka Kazuo Yao Makito Okamoto 《Nihon Jibiinkoka Gakkai kaiho》2003,106(3):220-225
To improve low-pitched voices in cases with polypoid vocal cords, YAG laser irradiation combined with a mucosal suturing technique was attempted in 9 female cases with severe polypoid changes in their vocal cords. A YAG laser beam (5 to 10 W) was used to irradiate the upper surface of the polypoid vocal cord. The polypoid content of the cord was gradually coagulated, and the free edge of the cord appeared to slide up toward the burned area. The polypoid content was then removed and squeezed through an open wound made in the burned area using a conventional method. Bleeding was successfully controlled using the laser. After the excessive mucosal margin was trimmed and the contour of the vocal cord was adjusted, the wound was closed by 7-0 monofilament absorbable suture. Suturing was relatively easy because the mucosal edge was also coagulated. Postoperative evaluations of voice quality revealed an improvement in the GRBAS scale of voice quality as well as an elevation in voice pitch and an upwards shift in the voice range in all cases. 相似文献
95.
96.
Reduced MLH1 expression after chemotherapy is an indicator for poor prognosis in esophageal cancers.
Kentaro Kishi Yuichiro Doki Masahiko Yano Takushi Yasuda Yoshiyuki Fujiwara Syuji Takiguchi Sontae Kim Ichiro Higuchi Morito Monden 《Clinical cancer research》2003,9(12):4368-4375
PURPOSE: Loss of function or expression of the mismatch repair gene MLH1 has been implicated in experimentally acquired resistance to cisplatin (CDDP) and other anticancer agents. The clinical significance of MLH1 expression was evaluated in advanced thoracic squamous cell carcinoma of the esophagus (ESCC) treated by neoadjuvant chemotherapy. EXPERIMENTAL DESIGN: We investigated MLH1 and P53 expression by immunohistochemistry in the surgical specimens of 107 patients who had undergone preoperative chemotherapy using CDDP along with 5-FU and ADM. These findings were correlated with the clinical outcome for this treatment. Biopsy samples before chemotherapy in 20 of these patients, and another 43 surgical specimens without chemotherapy, were also examined as control samples. RESULTS: In surgical specimens of ESCC, low MLH1 expression was not frequent without chemotherapy, whereas it was commonly observed after chemotherapy (14 versus 37%, P = 0.0057). Comparison between samples before and after chemotherapy revealed that MLH1 expression was unchanged during chemotherapy in 12 of 20 patients (60%) but was from high to low in 8 of 20 patients (40%). In the surgical specimen after neoadjuvant chemotherapy, MLH1 expression was not correlated with any clinicopathological factors, including the response to chemotherapy. However, low MLH1 showed poorer prognosis than high MLH1 (5-year survival 40.6 versus 19.3%, P = 0.0393), and in multivariate analysis, MLH1 was an independent prognostic factor for this multimodal treatment, following lymph node metastasis and clinical response to chemotherapy. Positive p53 expression, which was not affected by chemotherapy, was weakly associated with a poor response and clinical outcome, although this trend was not significant. CONCLUSIONS: In advanced ESCC, expression of MLH1 is reduced during CDDP-based chemotherapy, and this may partly account for poor postoperative survival. 相似文献
97.
Tetsuro Higuchi Takeo Iwama Keigo Yoshinaga Masahiro Toyooka Makoto M Taketo Kenichi Sugihara 《Clinical cancer research》2003,9(13):4756-4760
PURPOSE: The aim of this study was to examine the effect of a specific cyclooxygenase-2 inhibitor, rofecoxib, on rectal polyps in familial adenomatous polyposis patients. EXPERIMENTAL DESIGN: This was a randomized, double-blind, placebo-controlled study of the efficacy and safety of rofecoxib in the rectum. Initially, 21 patients were assigned randomly in a 1:1 ratio to receive either 25 mg rofecoxib once a day or a placebo p.o. for 9 months. Patients underwent endoscopy at the beginning of the study and then every 3 months thereafter. We reviewed the videotapes to measure the number and size of polyps in the same area throughout the study period in each individual patient. RESULTS: The polyp number, measured as the percentage of change from the baseline values, was significantly decreased in the rofecoxib group at 3, 6, and 9 months. At 9 months, the polyp number in the rofecoxib group decreased by 6.8% from the baseline values, whereas that in the placebo group increased by 3.1%. The 9.9% difference between the rofecoxib and placebo groups was statistically significant (P = 0.004). At 9 months, the rofecoxib group showed a significant reduction from the baseline in polyp size as compared with the placebo group (-16.2% versus 1.5%; P < 0.001). There was no statistically significant increase in the incidence of any adverse events in treatment with rofecoxib compared with placebo (P = 0.922). CONCLUSIONS: In this study, once-daily treatment with 25 mg rofecoxib, a cyclooxygenase 2-specific inhibitor, significantly decreased the number and size of rectal polyps in familial adenomatous polyposis patients. 相似文献
98.
Undifferentiated pancreatic cancer associated with humoral hypercalcemia of malignancy 总被引:1,自引:1,他引:1
Kakizaki S; Ohya N; Yoshinaga T; Higuchi T; Kitazawa R; Takayama H; Takagi H; Nagamine T; Mori M 《Japanese journal of clinical oncology》1998,28(9):563-566
We present a case of undifferentiated pancreatic cancer associated with
humoral hypercalcemia of malignancy (HHM) in which parathyroid
hormone-related protein (PTH-rP) is identified as the causative factor of
hypercalcemia. A 61-year-old man was hospitalized with right
hypochondralgia. Ultrasound examination and computed tomography
demonstrated a large mass in the pancreatic head with liver metastases.
Biopsy of the pancreatic tumor demonstrated undifferentiated carcinoma.
Serum calcium level and PTH-rP were elevated. Bone scan with technetium-99
demonstrated no accumulation in the bones. Immunohistochemical staining for
PTH-rP was weakly positive in the tumor cells. We considered that PTH-rP
was the causative factor of HHM in this case from laboratory data and
immunohistochemical findings. This rare case was successfully treated with
pamidronate disodium, which is a type of bisphosphonate derivative. We
compared this case with previously reported cases.
相似文献
99.
We describe a rare case of medulloblastoma in an adult woman with histological findings suggesting an origin for this neoplasm
in the external granular layer or its remnants. The patient presented with cerebellar dysfunction, and neuroimaging revealed
a right cerebellar mass lesion. Pathological examination of the operative specimen revealed a medulloblastoma with occasional
areas of neuronal or glial differentiation. Zic protein was also detected immunohistochemically in the tumor cells. The tumor
cells were mainly distributed in the subarachnoid space and extended to the cerebellar parenchyma through the perivascular
space to form tumor nodules. A suggestive finding, as concerns the origin of this neoplasm, was that the tumor cells were
also spread evenly along the subpial zone of the molecular layer, reminiscent of the cellular architecture of the fetal external
granular layer. 相似文献
100.
The expression of thrombomodulin and neural cell adhesion molecule (NCAM) was studied immunocytochemically in biopsied muscle specimens from 10 patients with rhabdomyolysis with different etiologic factors, including 5 with malignant hyperthermia. We have already reported that thrombomodulin was expressed on regenerating muscle cell membranes as well as on vessel walls in patients with various neuromuscular diseases, including Duchenne muscular dystrophy, Becker muscular dystrophy and inflammatory myopathy. We found increased expression of thrombomodulin not only on the sarcolemma, but also in the sarcoplasm of a fair number of muscle fibers in the acute phase of rhabdomyolysis. The granular pattern of thrombomodulin expression in the sarcoplasm seems to be a characteristic finding in the acute phase of rhabdomyolysis. Most muscle fibers which expressed NCAM on the sarcolemma also expressed thrombomodulin. However, the muscle fibers which expressed thrombomodulin in the sarcoplasm did not express NCAM, and showed a degenerative appearance on electron microscopic examination. These results suggest that thrombomodulin is expressed in the sarcoplasm during the acute degeneration phase of rhabdomyolysis in addition to the expression on the sarcolemma during the muscle fiber regeneration as shown in our previous study, and the former process, which is characterized by the granular expression of thrombomodulin in the sarcoplasm, may be a characteristic finding in rhabdomyolysis. 相似文献