45 research outputs found
Cilastatin Attenuates Cisplatin-Induced Proximal Tubular Cell Damage
A major area in cancer therapy is the search for protective strategies against cisplatin-induced nephrotoxicity. We investigated the protective effect of cilastatin on cisplatininduced injury to renal proximal tubular cells. Cilastatin is a specific inhibitor of renal dehydrodipeptidase I (DHP-I), which prevents hydrolysis of imipenem and its accumulation in the proximal tubule. Primary cultures of proximal cells were treated with cisplatin (1–30 M) in the presence or absence of cilastatin (200 g/ml). Apoptosis and mitochondrial injury were assessed by different techniques. Cisplatin uptake and DNA binding were measured by inductively coupled plasma spectrometry. HeLa cells were used to control the effect of cilastatin on the tumoricidal activity of cisplatin. Cisplatin increased cell death, apoptotic-like morphology, caspase activation, and mitochondrial injury in proximal tubular cells in a dose- and time-dependent way. Concomitant treatment with cilastatin reduced cisplatin-induced changes. Cilastatin also reduced the DNA-bound platinum but did not modify cisplatin-dependent up-regulation of death receptors (Fas) or ligands (tumor necrosis factor , Fas ligand). In contrast, cilastatin did not show any effects on cisplatintreated HeLa cells. Renal DHP-I was virtually absent in HeLa cells. Cilastatin attenuates cisplatin-induced cell death in proximal tubular cells without reducing the cytotoxic activity of cisplatin in tumor cells. Our findings suggest that the affinity of cilastatin for renal dipeptidase makes this effect specific for proximal tubular cells and may be related to a reduction in intracellular drug accumulation. Therefore, cilastatin administration might represent a novel strategy in the prevention of cisplatin-induced acute renal injury
Systematic investigation of projectile fragmentation using beams of unstable B and C isotopes
Background: Models describing nuclear fragmentation and fragmentation fission deliver important input for planning nuclear physics experiments and future radioactive ion beam facilities. These models are usually benchmarked against data from stable beam experiments. In the future, two-step fragmentation reactions with exotic nuclei as stepping stones are a promising tool for reaching the most neutron-rich nuclei, creating a need for models to describe also these reactions. Purpose: We want to extend the presently available data on fragmentation reactions towards the light exotic region on the nuclear chart. Furthermore, we want to improve the understanding of projectile fragmentation especially for unstable isotopes. Method: We have measured projectile fragments from C10,12-18 and B10-15 isotopes colliding with a carbon target. These measurements were all performed within one experiment, which gives rise to a very consistent data set. We compare our data to model calculations. Results: One-proton removal cross sections with different final neutron numbers (1pxn) for relativistic C10,12-18 and B10-15 isotopes impinging on a carbon target. Comparing model calculations to the data, we find that the epax code is not able to describe the data satisfactorily. Using abrabla07 on the other hand, we find that the average excitation energy per abraded nucleon needs to be decreased from 27 MeV to 8.1 MeV. With that decrease abrabla07 describes the data surprisingly well. Conclusions: Extending the available data towards light unstable nuclei with a consistent set of new data has allowed a systematic investigation of the role of the excitation energy induced in projectile fragmentation. Most striking is the apparent mass dependence of the average excitation energy per abraded nucleon. Nevertheless, this parameter, which has been related to final-state interactions, requires further study
Non-anti-D antibodies in red-cell alloimmunization
Universidade Federal de São Paulo, Escola Paulista Med, Dept Obstet, Fetal Med Sector, São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Obstet, Fetal Med Sector, São Paulo, BrazilWeb of Scienc