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71.
Peutz-Jeghers syndrome (PJS) is a rare disorder characterized by benign intestinal hamartomatous polyps and mucocutaneous pigmentation, and with an increased risk for intestinal and extra-intestinal neoplasms. Sertoli cell tumors in boys with PJS have been increasingly recognized as a cause of prepubertal gynecomastia. However, an association between nephrocalcinosis and PJS has not been reported before. We report on a 7.25-year-old boy with PJS, bilateral gynecomastia, Sertoli cell tumor and nephrocalcinosis, and present the outcome of 1-year treatment with the aromatase inhibitor testolactone. The patient presented with bilateral breast and testis enlargement, and mucocutaneous pigmentation. Testicular ultrasound revealed parenchymal multiple microcalcifications. Histopathological examination was consistent with Sertoli cell tumors. Nephrocalcinosis due to idiopathic renal hypercalciuria was also detected. The aromatase inhibitor testolactone was begun in an attempt to prevent acceleration in skeletal maturation. One-year treatment with testolactone reduced the breast base diameter from 7 to 3 cm, and bone age advanced 1.2 years during this period. Our case demonstrates that waiting for the effect of aromatase inhibitors on gynecomastia before making a decision for mastectomy may be a reasonable option. We also consider that the association between PJS and nephrocalcinosis may be a coincidence.  相似文献   
72.
Organization of Carboxysome Genes in the Thiobacilli   总被引:2,自引:0,他引:2  
The order of genes in the carboxysome gene clusters of four thiobacilli was examined and the possibility of the cluster forming an operon evaluated. Furthermore, carboxysome peptide homologs were compared with respect to similarities in primary sequence, and the unique structural features of the shell protein CsoS2 were described. Received: 27 March 2002 / Accepted: 30 April 2002  相似文献   
73.
Bioactivation of carbamate-based 20(S)-camptothecin prodrugs   总被引:2,自引:0,他引:2  
Two new prodrugs of CPT were synthesized, based on carbamate linkages between the 20-hydroxy group of CPT and a linker designed to be enzymatically removed by either Penicillin-G-Amidase or catalytic antibody 38C2. Cell growth inhibition assays showed an up-to-2250-fold difference in toxicity between the prodrugs and the active drug. A significant increase in toxicity was observed upon incubation of the enzyme or the catalytic antibody with the corresponding prodrug. The described derivatives of CPT further our knowledge in the design of prodrugs for use in selective approaches for targeted chemotherapy.  相似文献   
74.

Aim

To compare radiotherapy plans made according to CT and PET/CT and to investigate the impact of changes in target volumes on tumour control probability (TCP), normal tissue complication probability (NTCP) and the impact of PET/CT on the staging and treatment strategy.

Background

Contemporary studies have proven that PET/CT attains higher sensitivity and specificity in the diagnosis of lung cancer and also leads to higher accuracy than CT alone in the process of target volume delineation in NSCLC.

Materials and methods

Between October 2009 and March 2012, 31 patients with locally advanced NSCLC, who had been referred to radical radiotherapy were involved in our study. They all underwent planning PET/CT examination. Then we carried out two separate delineations of target volumes and two radiotherapy plans and we compared the following parameters of those plans: staging, treatment purpose, the size of GTV and PTV and the exposure of organs at risk (OAR). TCP and NTCP were also compared.

Results

PET/CT information led to a significant decrease in the sizes of target volumes, which had the impact on the radiation exposure of OARs. The reduction of target volume sizes was not reflected in the significant increase of the TCP value. We found that there is a very strong direct linear relationship between all evaluated dosimetric parameters and NTCP values of all evaluated OARs.

Conclusions

Our study found that the use of planning PET/CT in the radiotherapy planning of NSCLC has a crucial impact on the precise determination of target volumes, more precise staging of the disease and thus also on possible changes of treatment strategy.  相似文献   
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Sulfamerazine and sulfaguanidine are clenched with p-nitrobenzoyl chloride and the products obtained are reduced to NaxS in ethanol–water. Novel sulfonamides (6ag and 9ag) were synthesized by the reaction of these reduced products (4 and 8) with various sulfonyl chlorides (5ag). The structures of these compounds were characterized using spectroscopic analysis (IR, 1H-NMR, 13C-NMR and HRMS) technique. Antimicrobial activity of sulfonamides (3, 4, 7, 8, 6a–g and 9ag) was evaluated by the agar diffusion method. These compounds showed antimicrobial activity against tested microorganism strains (Gram-positive bacteria, clinic isolate and yeast and mold). Compounds 9d, 9e, 9a, 6d and 6e showed particularly antimicrobial activity against tested Gram-positive (Bacillus cereus and B. subtilis) and Gram-negative (Enterobacter aerogenes) bacteria.  相似文献   
77.
Background: We previously reported that ghrelin in saliva, orexigenic hormone that induces NPY release, was produced and released by salivary glands in humans. The purpose of this study was to investigate a possible circadian rhythm in saliva ghrelin concentration in human subjects as a function of time and meal. Saliva samples were collected at three-hour intervals throughout a 24-h period in 12 healthy volunteer males and ten healthy volunteer females who were provided with meals on a fixed schedule, and saliva collections were made within 15 minutes after each meal. Saliva ghrelin levels were measured by using a commercial radioimmunoassay (RIA) kit that uses 125I-labeled bioactive ghrelin as a tracer and a rabbit polyclonal antibody raised against full-length octanoylated human ghrelin. Immunohistochemical analysis of salivary glands was also performed. The results of this investigation indicated the following. (1) The saliva ghrelin level was slightly higher in female subjects in comparison with male subjects. (2) Saliva ghrelin levels were elevated before each meal and fell to trough levels after eating. (3) Saliva ghrelin levels showed a circadian rhythm that rose throughout the day to a zenith at 0300, then dropped at 0600 - 0900. (4) Saliva ghrelin also weakly correlated with BMI. (5) Immunohistochemical analysis showed that ghrelin was localized in the striated and excretory ducts of salivary glands of human. The present work is the first report of the circadian rhythm of saliva ghrelin level in human subjects as a function of time and meal. Meal plays an important role in lowering saliva ghrelin concentration in humans. However, present data did not exclude whether the circadian changes in saliva ghrelin expression were regulated by the biological clock or by food intake.  相似文献   
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Fibrosarcoma is one of the fatal cancer types and there is still not satisfactory success in its treatment despite new drugs. Therefore, the search for a new compound has been going on. It is currently known that some palladium-based anti-cancer compounds seem to have powerful apoptosis-inducing effects in cancer cells. For this purpose, a palladium(II)-saccharinate complex containing terpyridine which was synthesized by our research group was investigated in terms of its anti-tumor effects against mouse embryonic fibroblast NIH/3T3 (normal cell line) and rat embryonic fibroblast 5RP7 (H-ras transformed cell line) in vitro. The MTT and ATP viability assays were used to determine anti-growth/cytotoxic effects. Cytotoxic activity was confirmed by real time cytotoxicity analysis system. Flow cytometry analysis was further used to determine the mode of cell death (apoptosis/necrosis). Apoptosis was confirmed by triple-staining the cells with Hoechst 33342/PI/Calcein-AM triple and evaluated with fluorescence microscopy. It was found that the compound showed significant anti-growth activity by inducing apoptosis in a dose dependent manner. In conclusion, taking into account the cytotoxic activity of the compound at even relatively lower doses, in vivo experiments to elucidate its potential use for the treatment of fibrosarcoma are warranted.  相似文献   
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