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Transplantation animal models require 2 animals for each experiment, 1 as a donor and 1 as a recipient. At the present time, developing microsurgical instruments and refining surgical techniques should allow us to reduce the number of animal used for transplantation research. In this study, we aimed to harvest 2 kidneys from 1 donor to be able to minimize the number of animals needed for transplantation studies. For this purpose, we developed a kidney xenotransplantation model from mouse to rat, in which only 1 animal was used as the donor for 2 kidney recipients. Ten male Balb/c mice weighing from 25 to 30 g were used as donors, and 20 male Sprague-Dawley rats weighing from 150 to 200 g were used as recipients. In this study, the harvesting of 2 kidneys from a mouse as well as the recipient operation were described with technical detail. Although harvesting 2 kidneys from a mouse and mouse-to-rat kidney xenotransplantation is a highly challenging microsurgical procedure, we believe that every experienced surgeon should be capable of performing this surgery with some practice. This model allows us to reduce the number of animals in transplantation studies without compromising the graft quality. We strongly recommend our refined harvesting technique to researchers, particularly in terms of animal rights. [ABSTRACT FROM AUTHOR]

Raman frequencies of six lattice modes are calculated as a function of pressure using the volume data from the literatüre by means of the isothermal mode Grüneisen parameter ( γ T ) for the solid phase I of benzene. We find that by determining the γ T decreasing, the Raman frequencies calculated for the phonon modes increase with increasing pressure in this solid phase of benzene, which agree with the observed Raman data. We also predict the T-P phase diagram between the solid phases of I and I′ by using the calculated Raman frequencies of the six lattice modes of benzene. Our calculated T-P diagram does not match properly with the observed data, which needs to be reconsidered by analyzing a number of measurements for the I − I′ transition in benzene. Our results indicate that this method of calculating the Raman frequencies from the volume data through the mode Grüneisen parameter and predicting the T-P phase diagram from the calculated Raman frequencies, is adequate and it can also be applied to some other hydrocarbons such as naphthalene and anthracene. [ABSTRACT FROM AUTHOR]

The aim of this study is to evaluate gamma ray shielding properties for bismuth doped barite-based ternary polymer composite materials. In the first stage of the study, a polymer matrix was prepared by combining orthophthalic unsaturated polyester resin (OUP), Methyl Ethyl Ketone Peroxide (MEKP) and Cobalt Octoate (6%) (Co-6). Then, barite and bismuth were added in certain proportions as filler material into this polymer matrix and thus ternary composites were produced. Experimental studies for the produced samples were carried out in narrow beam geometry using HPGe detector and 133Ba, 22Na, 137Cs, 60Co radioactive sources which emit photons between 276.4 and 1332.5 keV energy. To determine the gamma ray shielding properties of the produced ternary composites, radiation protection efficiency (RPE), linear attenuation coefficient (μ), mass attenuation coefficient (μ/ρ), half value layer (HVL), tenth value layer (TVL), mean free path (MFP), effective atomic number (Z eff), effective electron density (N E) parameters were obtained. Experimental results were compared with theoretical results obtained with WinXCOM software and GEANT4 Monte Carlo simulation code. Experimental and theoretical results were found to be compatible with each other. According to obtained results, it was found that the sample with the best shielding property among the prepared samples was BaBi50 coded sample. • Barite-based ternary composites were fabricated. • Their gamma shielding capacities were investigated. • Experimental, theoretical and GEANT4 methods were used. • Good agreement was observed between the used methods. • The composite coded as BaBi50 provided better shielding than the other. [ABSTRACT FROM AUTHOR]

Objectives: The predictive value of preoperative hemoglobin (HB) level on the outcome of patients undergoing valve surgery is not well established. This study evaluated the predictive value of preoperative HB level on survival after aortic valve replacement (AVR). Design: This was a retrospective analysis of prospectively collected data. Setting: A single-center study performed in an educational hospital. Participants: All consecutive patients (n = 1,808) who underwent AVR between January 1998 and December 2010. Interventions: AVR. Measurements and Main Results: Patients were classified into 4 groups according to the preoperative HB level: very low (HB of <12g/dL in men and <11g/dL in women), low (HB of 12-13g/dL in men and 11-12g/dL in women), normal (HB of 13-14.5g/dL in men and 12-13.5g/dL in women), and high normal (HB of ≥14.5g/dL in men and ≥13.5g/dL in women). The mean follow-up duration was 5.58±3.5 years, and the median follow-up duration was 5.38 years. The mean preoperative HB was 14±1.6g/dL for men and 13.0±2.1g/dL for women. Early mortality (≤30 days) was 6.1% in the very-low-HB group, 5.4% in the low-HB group, 3.2% in the normal HB group, and 2.3% in the high-normal-HB group (p = 0.37). Late mortality (>30 days) was 26.1% in the very-low-HB group, 23.7% in the low-HB group, 17.1% in the normal-HB group, and 12.6% in the high-normal-HB group (p<0.0001). The multivariate logistic regression model did not identify low HB as an independent predictor for early mortality. Cox regression multivariate analysis revealed both HB level, as a continuous variable, (p = 0.006), and very-low-HB level (p<0.0001), as independent predictors of late mortality. Cox regression analyses, corrected for confounders, demonstrated that low-HB level is an independent predictor for higher overall mortality (hazard ratio = 2.00, CI 1.41-2.85, p≤0.0001). Conclusions: In patients undergoing AVR, preoperative low-HB level is an independent risk factor for late mortality, but not for early mortality. [Copyright &y& Elsevier]

Abstract: Introduction: Recurrent glomerular diseases are important causes of graft dysfunction after renal transplantation. As the outcomes of transplantation continue to improve, the problem of recurrent diseases in the transplanted kidney have become evident. The purpose of our study was to determine the risk factors for and the incidence of recurrence in the posttransplant period as well as their impact on graft survival rates. Method: We retrospectively analyzed 49 patients with glomerular diseases due to membranoproliferative glomerulonephritis (n = 26); focal segmental glomerulosclerosis (FSGS, n = 18); and systemic lupus erythematosus (n = 5). The mean follow-up was 9.5 years. Results: Recurrent disease was detected in 30 of 49 patients after a mean posttransplant follow-up of 28.1 months (range = 1 to 157) and their average graft survival was 41.3 months. Nineteen patients were recurrence-free with a mean graft survival of 79.4 (range = 15 to 158) months (P < .05). One patient with FSGS, showed disease-recurrence in her third transplant after having experienced recurrences in the former grafts. In all six patients with HLA haplotype B8, recurrence was observed at a mean of 19.5 ± 9.8 months. The only risk factor that was identified was this HLA haplotype. Conclusion: Recurrent disease a significant problem after renal transplantation is associated with decreased graft survival. The donor HLA type may be associated with risk, which should be clearly discussed with both the living donor and the recipient candidate. [Copyright &y& Elsevier]