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This paper presents an improved switched‐inductor quasi‐Z‐source inverter with a higher boost factor than similar inverters, which integrates a switched‐capacitor and a three‐winding switched‐coupled inductor into a conventional quasi Z‐source inverter (q‐ZSI). The proposed inverter is called a switched‐capacitor trans quasi Z‐source inverter (SCT‐q‐ZSI). In this topology, the input current is continuous, and a high voltage gain is reachable with lowduty cycles (D). In this structure, capacitors are used instead of the side diodes of the switched‐inductor quasi Z‐source inverter. The proposed converter has a low inrush current at the startup which might damage the converter components. The performance of the proposed inverter is investigated at different operating modes and the voltage and current equations of all elements are calculated. The analysis, derivation of boost factor, capacitor voltages, and components, of the proposed inverter, are carried out and are compared with similar inverters. Finally, analytical, simulation, and experimental results are also presented to validate its advantages. [ABSTRACT FROM AUTHOR]

The Z‐source inverter was introduced to overcome shortcomings of voltage source inverter and current source inverter. In this paper, the concept of one switched‐inductor Z‐source inverter is extended to switched‐capacitor inductor ZSI with an impedance network. In the proposed inverter, capacitors are used instead of the side diodes of the one switched inductor Z‐source inverter. The proposed inverter has a higher boost factor compared to One SL‐ZSI and quasi‐ZSI. Also, it has lower voltage stress compared to similar inverters. The proposed inverter can be extended to n cases in cascade form. The components used in the proposed topology are lower than the SL‐ZSI. The analysis, derivation of boost factor, capacitor voltages, diode voltages, and switch voltages stress of the proposed inverter topology are carried out and are compared with the similar inverters. The advantages of the proposed structure are verified through simulation and implementation. The simulation is performed in MATLAB/SIMULINK. [ABSTRACT FROM AUTHOR]

PR81 is a monoclonal antibody that binds with high affinity to MUC1, which is over expressed on breast and other tumors. The objective of this study was to compare the two labeling methods (direct and indirect radioiodination) for application of this antibody against MUC1 as a radioimmunotherapeutical agent.Monoclonal antibody (PR81) against the tandem repeat of the core protein (MUC1) was prepared, characterized, purified, and labeled with ^{131}I using the direct (chloramin-T) and indirect (Fmoc-D-Tyr (tBu)-D-Tyr (tBu)-D-Lys (Boc)-OH (YYK) attached to N-hydroxysuccinimide as a linker between PR81 and ^{131}I) methods. The immunoreactivity of ^{131}I-PR81 and ^{131}I-TP-PR81 complexes with MUC1 (the native protein), BSA-P_{20} (a 20 amino acid corresponding the tandem repeat of MUC1) and MCF7 cell line were performed by RIA. In vitro stability of ^{131}I-PR81 and ^{131}I-YYK-peptide-PR81 complexes in human serum was determined by thin layer chromatography (TLC). Cell toxicity and in vitro internalization studies were performed with the MCF7 cell line, and the tissue biodistribution of the ^{131}I-PR81 and ^{131}I- YYK-peptide -PR81 complexes was evaluated in normal BALB/c mice at 4, 24 and 48 hrs. The labeling efficiency was determined by measuring the percentage recovery of radioactivity in the final product relative to the initial activity in the shipment vial, was found to be 59.9% ± 7.9% for direct and 50% ± 3.2% for indirect methods. ^{131}I-PR81 and ^{131}I- YYK- peptide -PR81 complexes showed high immunoreactivity towards MUC1 protein, BSA-P_{20} and MCF7 cell line. In vitro stability of the labeled products in human serum which was measured by thin layer chromatography (TLC) was found to be more than 50% over 24 hr for ^{131}I-PR81 and 70% for ^{131}I- YYK-peptide -PR81 complexes. Cell toxicity and in vitro nternalization studies showed that the ^{131}I-PR81 and ^{131}I- YYK-peptide -PR81 complexes inhibited 80% growth of the MCF7 cultured cell lines in vitro in a high concentration and up to 40% of the ^{131}I-PR81 and 60% of the ^{131}I- YYK-peptide -PR81 complexes internalized after 24 h. Biodistribution studies were performed in normal BALB/c mice at 4, 24 and 48 hrs post-injection. Thyroid and stomach levels from PR81 labeled with ^{131}I- YYK-peptide were two- to three- fold less than those with directly labeled ^{131}I-PR81, suggesting low recognition of its D-iodotyrosine residue by endogenous deiodinase. These results show that the indirect labeling was better than the indirect labeling and ^{131}I- YYK-peptide -PR81 may be considered as a promising candidate for therapy of breast cancer. [ABSTRACT FROM AUTHOR]

Purpose. Insulin like growth factor receptor 1 (IGF-1R) is well-documented to play a key role in radiation response and tumor radiosensitivity, thus offering an attractive clinic drug target to enhance tumor sensitivity to anti-cancer radiotherapy. Material and methods. Human colon carcinoma SW480 cells were transfected with the specific small interference RNA (siRNA) expression vector (pkD-shRNA-IGF-1R-V2) designed to target IGF-1R mRNA. The expression of IGF-1R mRNA and its protein among the transfected and untransfected cells were detected by semi-quantitative RT-PCR and ELISA assay. The changes in cell radiosensitivity were examined by MTT assay. Results. Transfection of mammalian expression vector pkD containing IGF-1R siRNA was shown to reduce IGF-1R mRNA levels by up to 95%. ELISA assay detected a similar inhibition of IGF-1R protein levels in cells transfected with IGF-1R siRNA. SW480 cells transfected with the expression vector for siRNA significantly rendered cells more sensitive to radiation and the highest radiation enhancement ratio was 2.02 ± 0.08. Conclusion. These data provide the first evidence that specific siRNA fragment (pkD-shRNA-IGF-1R-V2) targeting human IGF-1R mRNA is able to enhance colon cancer radiosensitivity. Also results indicated that, combining IGF-1R siRNA and radiation significantly enhances antitumor efficacy compared with either modality alone. [ABSTRACT FROM AUTHOR]

Abstract: Technetium-99m complex of hexamethyl-propylene-amineoxime (HMPAO) is used as an efficient agent to label liposomes. For this, 99mTc-HMPAO is incubated with preformed liposomes that contain glutathione (GSH). Effect of GSH and lipid concentration on labeling efficiency, as well as the effect of lipid composition on in vitro stability of labeled liposomes, was investigated in the present study. d,l-HMPAO was synthesized and kits including d,l-HMPAO and SnCl2·2H2O were optimized at 0.5 mg HMPAO, 5.0 μg SnCl2·2H2O and pH 7, and lyophilized. DSPC/CHOL (molar ratio 2:1) liposomes encapsulating GSH were labeled with 99mTc-HMPAO prepared kits. Increase of GSH concentration in hydration buffer from 5 to 200 mM during liposome preparation resulted in a broad labeling efficiency of liposomes ranging from 4.16% to 69.81%. An initial approximate concentration of 100 mM GSH in the hydration buffer seems to be appropriate for a good labeling efficiency. At the optimum concentration of GSH, change of the total initial lipid concentration from 10 to 70 mM did not produce a remarkable difference in labeling efficiency. Study of the effect of lipid composition on the stability of liposomes showed that all three kinds of labeled liposomes composed of DSPC/CHOL, DPPC/CHOL and DMPC/CHOL (molar ratio 2:1) had good in vitro stability in human plasma at 37°C for 48 h; however, employing DSPC resulted in the most stable ones. [Copyright &y& Elsevier]