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The impact of the solvent on the photodissociation of embedded molecules has been intensively investigated in the last decades. Collisions of photofragments with the solvating atoms or molecules can change their kinetic energy distribution or even lead to the de-excitation of the dissociating molecule to a bound electronic state quenching the dissociation. In this article we show that this cage effect is strongly enhanced if interatomic Coulombic decay (ICD) of the excited state becomes allowed. Ab initio calculations in H2O-Cl- cluster show that the ultra-fast dissociation of water in the à excited state is strongly quenched by ICD. We found that this very efficient quenching is due to two factors. First, the lifetimes of the ÃA state due to ICD are short ranging between 6 and 30 fs. Second, nuclear dynamics is dominated by the chattering motion of the H atom between O and Cl- allowing ICD to act for longer times. We hope that this work will be an important first step in clarifying the impact of ICD on photodissociation of embedded molecules. [ABSTRACT FROM AUTHOR]

For computational rovibrational spectroscopy the choice of the frame is critical for an approximate separation of overall rotation from internal motions. To minimize the coupling between internal coordinates and rotation, Eckart proposed a condition [“Some studies concerning rotating axes and polyatomic molecules," Phys. Rev.47, 552–558 (1935)] and a frame that fulfills this condition is hence called an Eckart frame. A method is developed to introduce in a systematic way the Eckart frame for the expression of the kinetic energy operator (KEO) in the polyspherical approach. The computed energy levels of a water molecule are compared with those obtained using a KEO in the standard definition of the Body-fixed frame of the polyspherical approach. The KEO in the Eckart frame leads to a faster convergence especially for large J states and vibrationally excited states. To provide an example with more degrees of freedom, rotational states of the vibrational ground state of the trans nitrous acid (HONO) are also investigated. [ABSTRACT FROM AUTHOR]

Generalized curvilinear coordinates, as, e.g., polyspherical coordinates, are in general better adapted to the resolution of the nuclear Schrödinger equation than rectilinear ones like the normal mode coordinates. However, analytical expressions of the kinetic energy operators (KEOs) for molecular systems in polyspherical coordinates may be prohibitively complicated for large systems. In this paper we propose a method to generate a KEO numerically and bring it to a form practicable for dynamical calculations. To examine the new method we calculated vibrational spectra and eigenenergies for nitrous acid (HONO) and compare it with results obtained with an exact analytical KEO derived previously [F. Richter, P. Rosmus, F. Gatti, and H.-D. Meyer, J. Chem. Phys. 120, 6072 (2004)]. In a second example we calculated π → π* photoabsorption spectrum and eigenenergies of ethene (C2H4) and compared it with previous work [M. R. Brill, F. Gatti, D. Lauvergnat, and H.-D. Meyer, Chem. Phys. 338, 186 (2007)]. In this ethene study the dimensionality was reduced from 12 to 6 by freezing six internal coordinates. Results for both molecules show that the proposed method for obtaining an approximate KEO is reliable for dynamical calculations. The error in eigenenergies was found to be below 1 cm-1 for most states calculated. [ABSTRACT FROM AUTHOR]

Objective(s): : Renal ischemia-reperfusion injury (IRI) as a severe condition of acute kidney injury (AKI) is the most common clinical problem with high mortality rates of 35-60% deaths in hospital. Mesenchymal stem cells (MSC) due to unique regenerative characteristics are ideal candidates for the treatment of the ischemic injuries. This work is focused on the administration of MSC to IRI-induced AKI Wistar rats and evaluating their significance in AKI treatment. Material and Methods: Animals underwent surgical procedure and AKI was induced by 40 min bilateral renal pedicle clamping. Immediately after reperfusion, 2×106 rat bone marrow derived MSCs were injected via intra-parenchymal or intra-aortic route. Results: Animals subjected to AKI after days 1 and 3 showed significant increase in the serum creatinine and blood urea nitrogen (BUN) concentration along with a declined glomerular filtration rate (GFR) when compared with non-ischemic animals. On the other hand, treated animals showed a significant enhanced regeneration as compared to ischemic animals in both administration route groups. Conclusion: According to the results concluded from the renoprotective effects of MSC in IRI/AKI, MSCs could be considered as promising therapeutic approach for AKI in clinical applications. [ABSTRACT FROM AUTHOR]

Vulvar cancer is a rare gynecological malignancy with mainly lymphatic spread. Sentinel node mapping plays an important role in the management of this gynecological malignancy. In the current study, we reported our experience in sentinel node mapping of vulvar cancer and review the literature accordingly. Since the introduction of sentinel node mapping to the surgical oncology community of our university in 2004, we had two operable vulvar cancer patients who were candidate for sentinel node mapping for inguinal lymph node staging. In the current study, we reported these two cases in details and a brief review of literature on sentinel node mapping in vulvar cancer was done. We specifically discussed the overall accuracy, importance of blue dye injection, learning curve effect, frozen section, excisional biopsy and location of the tumors. Overall sentinel node mapping is a safe and effective method for inguinal lymph node staging in vulvar cancers. In order to perform sentinel node mapping efficiently, paying attention to the details is of utmost importance. [ABSTRACT FROM AUTHOR]

Introduction: Several radiotracers are being used for sentinel node mapping in patients with breast cancer. In the current study, we reported our experience with 99m-Tc Phytate for sentinel node mapping in Mashhad University of Medical Sciences. Methods: All breast cancer patients who underwent sentinel node mapping using 99m-Tc Phytate were included. All patients received intradermal peri-areolar injection of 0.5 mCi/0.1cc 99m-Tc Phytate. Lymphoscintiraphy was performed for 145 patients 5-10 minutes post-injection. The sentinel nodes were found during surgery using a hand-held gamma probe as well as blue dye technique. Results: In total 165 patients were evaluated. Lymphoscintigraphy showed axillary sentinel nodes in 135 out of 145 patients (93%) following imaging. At least one sentinel node could be detected in all these 135 patients during surgery. In the remaining 10 patients with sentinel node non-visualization, 5 had sentinel node harvesting failure during surgery. Median number of sentinel nodes on the lymphoscintigraphy images was 1. Sentinel node detection rate was 95% (157/165). In the 8 patients with sentinel node harvesting failure, 7 had pathologically involved axilla. Median number of harvested sentinel nodes was 1. Mean sentinel node to background count ratio was 10±2. Conclusions: 99m-Tc Phytate is an effective and highly successful radiotracer for sentinel node mapping. Sentinel node can be visualized in a short time after 99m-Tc Phytate injection on the lymphoscintigraphy images. The sentinel to background count during surgery is high which results in more convenient sentinel node harvesting and high detection rate. [ABSTRACT FROM AUTHOR]

Introduction: Many radiotracers have been used for sentinel node mapping with acceptable results. The main difference between these radiotracers is the particle size. In the current study, we reported defective labeling of Tc-99m antimony sulfide colloid which resulted in large particle size. Methods: Tc-99m-Antimony sulfide colloid was used for axillary sentinel node mapping of 45 breast cancer patients. The prepared kits were turbid and were used for the first 15 patients. For the remaining 30 patients, we used a filter (GyroDisc CA-PC Cellulose Acetate Membrane; 30 mm; Pore size: 0.2 μm) after labeling to remove the possible large particles of the prepared kits. Results: On the lymphoscintigraphy images, at least one sentinel node could be identified in 5 and 29 patients of the unfiltered and filtered groups respectively (p=0.00001). Sentinel node detection by gamma probe was successful in 5 and 30 patients in the unfiltered and filtered groups respectively (p=0.000001). Conclusion: Tc-99-Antimopny sulfide colloid is a suitable radiotracer for sentinel node mapping of the breast cancer patients. In case of any unusual turbidity of the labeled kit, it should not be used or at least be filtered before injection. [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]