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71.
72.
Rab3D is a small GTP-binding protein associated with secretory vesicles in various exocrine and endocrine cells, where it has been implicated in regulated exocytosis. Data obtained previously in pancreas have suggested that rab3D is involved in the coating of secretory granules with filamentous actin. In the present study we employed Western blot analysis, immunofluorescence, and immunoelectron microscopy to examine the distribution of rab3D in rat lung. Rab3D immunoreactivity was detected in bronchiolar Clara cells and alveolar epithelial type II (AET-II) cells. In both cell types, rab3D displayed preferential localization to secretory vesicles that were identified using specific antibodies against Clara Cell Secretory Protein and p180 lamellar body protein, respectively. Interestingly, rab3D was associated with only 24% of the lamellar bodies in AET-II cells. Rab3D-positive lamellar bodies were typically in close proximity of the apical plasma membrane, where exocytosis occurs. Another subpopulation of lamellar bodies, constituting only 2%, was not only rab3D-positive but could also be labeled with the filamentous-actin probe phalloidin. A third subpopulation, constituting 9%, displayed actin coating without rab3D staining. We propose that these three lamellar body subpopulations represent consecutive intermediates along the regulated exocytotic pathway, implying that rab3D release and actin coating are intimately linked processes.  相似文献   
73.
The aim of this study was to investigate the direct iodination of the recently discovered peptide obestatin by LC-UV/ESI ion trap MS analysis. The influence of selected reaction parameters on obestatin iodination by chloramine-T, Iodo-Gen((R)) and lactoperoxidase was investigated by experimental design. Different responses, i.e. species percentage and yield, peptide recovery and iodination yield were evaluated. Mono-up till tetra-iodinated species are possible depending on the reaction conditions with electrophilic substitutions occurring at Tyr(16) and His(19) as confirmed by LC/MS/MS. The two possible mono-iodinated obestatin isomers, i.e. [I(1)-Tyr(16)]-obestatin and [I(1)-His(19)]-obestatin, could be chromatographically separated. Several significant main and quadratic effects, and interaction of factors were observed from which optimum conditions for a specific response could be derived. The highest impact on the response surface diagrams was overall attributed to the amount of iodide added. Synthesis methods were compared relative to the different response factors: lactoperoxidase was found to be the overall most robust iodination technique, and also gave the highest mono-iodinated species yield. The applicability of our research was demonstrated by non-carrier-added (125)I-radioiodination. To our knowledge, this is the first time an LC separation of mono-iodinated peptide isomers has been reported.  相似文献   
74.
Identification of Neisseria gonorrhoeae by the Bruker matrix-assisted laser desorption ionization−time of flight mass spectrometry (MALDI-TOF MS) system may be affected by “B consistency categorization.” A supplementary database of 17 N. gonorrhoeae main spectra was constructed. Twelve of 64 N. gonorrhoeae identifications were categorized with B consistency, which disappeared using the supplementary database. Database extension did not result in misidentification of Neisseria meningitidis.  相似文献   
75.
BackgroundWeekly paclitaxel/cisplatin is effective in platinum-resistant epithelial ovarian cancer (EOC). To reduce toxicity, paclitaxel/cisplatin was replaced by paclitaxel/carboplatin.Patients and methodsPatients with progressive EOC after prior 3-weekly paclitaxel/carboplatin were treated with six cycles weekly paclitaxel 90 mg/m2 and carboplatin area under the curve (AUC) 4 mg/ml/min, followed by six cycles 3-weekly paclitaxel/carboplatin. End-points were progression free survival (PFS), overall survival (OS), response rate (RR) and toxicity.ResultsMedian progression free interval after last platinum was 9 (0–81) months in 108 patients; 43 were platinum-resistant, of whom 13 started weekly paclitaxel/carboplatin <6 months after progression. During 633 weekly cycles grade 3/4 toxicity included; thrombocytopenia 8%, neutropenia 30%, febrile neutropenia 0.5%. Non-haematologic toxicity was low. Treatment was delayed in 16%, and dose reduced in 2% of cycles. RR was 58% for platinum-resistant and 76% for platinum-sensitive patients, median PFS were 8 (range 1–21) and 13 (1–46) months, median OS 15 (1–69) and 26 (4–93) months, respectively. The 13 platinum-resistant patients with a platinum-therapy free interval <6 months had a significant shorter PFS (4 versus 10 months, p = 0.035) and OS (9 versus 15 months, p = 0.002).ConclusionSix cycles weekly paclitaxel/carboplatin followed by six 3-weekly cycles is well-tolerated and highly active in platinum-resistant and platinum-sensitive patients.  相似文献   
76.
A controlled release pellet formulation using a NanoCrystal colloidal dispersion of ketoprofen was developed. In order to be able to process the aqueous NanoCrystal colloidal dispersion into a hydrophobic solid dosage form a spray drying procedure was used. The in vitro dissolution profiles of wax based pellets loaded with nanocrystalline ketoprofen are compared with the profiles of wax based pellets loaded with microcrystalline ketoprofen and of a commercial sustained release ketoprofen formulation. Pellets were produced using a melt pelletisation technique. All pellet formulations were composed of a mixture of microcrystalline wax and starch derivatives. The starch derivatives used were waxy maltodextrin and drum dried corn starch. Varying the concentration of drum dried corn starch increased the release rate of ketoprofen but the ketoprofen recovery remained problematic. To increase the dissolution yield surfactants were utilised. The surfactants were either added during the production process of the NanoCrystal colloidal dispersion (sodium laurylsulphate) or during the pellet manufacturing process (Cremophor RH 40). Both methods resulted in a sustained but complete release of nanocrystalline ketoprofen from the matrix pellet formulations.  相似文献   
77.
BACKGROUND: In breast cancer, there is an inverse relationship between HER2/neu overexpression and receptors for estrogen (ER) or progesterone (PR). Some clinical observations such as the age-related association between hormone receptors and tumour grade, which predicts HER2/neu overexpression, suggest an age-related relationship. PATIENTS AND METHODS: Our study population consisted of 1362 consecutive women receiving primary surgery for non-metastatic invasive breast cancer. We compared the relationship between both hormone receptors and HER2/neu overexpression in different age groups taking other tumour characteristics into account. RESULTS: In a multivariate model, considering the overall group, a negative ER, a negative PR and a high tumour grade were predictive for HER2/neu overexpression (P <0.001). Considering 246 women aged < or =45 years, the only predictor for HER2/neu overexpression in this age category was a high tumour grade (P = 0.003). Considering the 1116 women aged >45 years, ER (P = 0.001), PR (P = 0.001) and tumour grade (P <0.001) were associated with HER2/neu (P <0.001). CONCLUSION: Our findings indicate that the association between ER, PR and HER2/neu overexpression varies with age. The hormone receptors are not an independent predictor for the HER2/neu status in young women while they are in elder patients.  相似文献   
78.
It is clear that primary debulking remains the standard of care within the treatment of advanced ovarian cancer (International Federation of Gynaecology and Obstetrics, FIGO, stage III and IV). Debulking surgery should be performed by a gynaecologic oncologist without any residual tumour load, or so called optimal debulking'. Over the last decades, interest in the use of neoadjuvant chemotherapy together with an interval debulking has increased. Open laparoscopy is probably the most valuable tool for evaluating the operability primarily or at the time of interval debulking surgery. Neoadjuvant therapy can be used for patients that are primarily suboptimally debulked due to an extensive tumor load. In this situation, based on the randomized EORTC-GCG trial, interval debulking by an experienced surgeon improves survival in some patients who did not undergo optimal primary debulking surgery. Based on the GOG 152 data, interval debulking surgery does not seem to be indicated in patients who underwent primarily a maximal surgical effort by a gynecological oncologist. Neoadjuvant chemotherapy can also be used as an alternative to primary debulking. In retrospective analyses neoadjuvant chemotherapy followed by interval debulking surgery does not seem to worsen prognosis compared to primary debulking surgery followed by chemotherapy. However, we will have to wait for the results of future randomized trials to know whether neoadjuvant chemotherapy followed by interval debulking surgery is a good alternative to primary debulking surgery in stage IIIc and IV patients.  相似文献   
79.
80.
Introduction Prognostic subgroup classification of operable breast cancers using cDNA clustering of breast cancer-related genes resembles the classification based on the combined immunohistochemical (IHC) expression of the hormone and HER-2 receptors. We here report the short-term disease-free interval (DFI) of operable breast cancers by their joint hormone receptor/HER-2 phenotype. Patients and methods Short-term follow-up (FU) of a prospective cohort of 1,958 breast-cancer patients primary operated at our institution between 2000 and 2005. Receptors were evaluated using IHC. Steroid receptors were considered positive for any nuclear staining; HER-2 for strong (3+) membrane staining or positive fluorescence in situ hybridization (FISH). Kaplan–Meier (KM) DFI curves were calculated for any relapse defined as a local, regional, contralateral, or distant breast cancer event for the six predefined breast cancer subgroups: ER + PR + HER-2 − (PPN), ER + PR − HER-2 − (PNN), ER + PR + HER-2 + (PPP), ER – PR − HER-2 − (NNN), ER – PR − HER-2 + (NNP), and ER + PR − HER-2 + (PNP). P-values were calculated for comparison of the six different survival curves using two possible adaptations for multiple testing. A multivariate model for the receptors predicting DFI did incorporate local and systemic adjuvant therapy. Results Median patient age was 57 years (ranges 26–96) and median FU was 3.35 years. Overall, DFI at median FU was 91%; 94% for PPN, 89% for PNN, 86% for NNN, 81% for PPP, 80% for PNP, and 76% for NNP cases. Some receptor subgroups had a significantly better DFI than others based on multiple testing, especially when the PPN group was compared against the four most frequent subtypes. The multivariate model with local and systemic adjuvant therapy confirmed the prognostic value of ER, PR, and HER-2 for short-term DFI. Conclusion It is possible to distinguish short-term prognostic breast cancer subgroups only on the basis of ER, PR, and HER-2 even when stratified for local and systemic adjuvant therapy. While gene expression profiles based on microarray data of over hundreds of genes will probably teach us much about breast cancer biology, heterogeneity, and prognosis, we emphasize the important short-term prognostic value of currently used IHC markers for ER, PR, and HER-2.  相似文献   
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