12 research outputs found
Cancer incidence in kidney transplant recipients: a study protocol
<p>Abstract</p> <p>Background</p> <p>Different publications show an increased incidence of neoplasms in renal transplant patients. The objective of this study is to determine the incidence of cancer in the recipients of renal transplants performed in the A Coruña Hospital (Spain) during the period 1981–2007.</p> <p>Methods/Design</p> <p>During the study period 1967 kidney transplants were performed, corresponding to 1710 patients. Patients with neoplasms prior to the transplant will be excluded (n = 38). A follow-up study was carried out in order to estimate cancer incidence after transplantation.</p> <p>For each patient, information included donor and recipient characteristics, patients and graft survival and cancer incidence after transplantation. Incident cancer is considered as new cases of cancer after the transplant with anatomopathological confirmation. Their location will be classified according to the ICD-9.</p> <p>The analysis will be calculated using the indirect standardisation method. Age-adjusted cancer incidence rates in the Spanish general population will be obtained from the Carlos III Health Institute, the National Epidemiology Centre of the Ministry of Science and Technology. Crude first, second and third-year post-transplantation cancer incidence rates will be calculated for male and female recipients. The number of cases of cancer at each site will be calculated from data in the clinical records. The expected number of cancers will be calculated from data supplied by the Carlos III Health Institute. For each tumour location we will estimate the standardized incidence ratios (SIRs), using sex-specific cancer incidence rates, by dividing the incidence rate for the transplant patients by the rate of the general population. The 95% confidence intervals of the SIRs and their associated p-values will be calculated by assuming that the observed cancers follow a Poisson distribution. Stratified analysis will be performed to examine the variation in the SIRs with sex and length of follow-up.</p> <p>Competing risk survival analysis methods will be applied to estimate the cumulative incidence of cancer and to identify variables associated to its occurrence.</p> <p>Discussion</p> <p>Information about cancer incidence in kidney transplant patients could be useful to adapt the guidelines on post-kidney transplant follow-up on tumour screening, and evaluate the impact of intervention measures for the prevention of cancer in these patients.</p
Synthesis and Characterization of Some Chiral Metal-Salen Complexes Bearing a Ferrocenophane Substituent
The C2-symmetrical “salen” ligand (+)-9 bearing two [5]ferrocenophane substituents has been prepared in five steps starting from readily available diacetylferrocene, p-hydroxybenzaldehyde and (R,R)-N,N’-diphenylethylenediamine. Reaction of (+)-9 with Mn(OAc)3, Co(OAc)2 ZnEt2 or UO2(OAc)2 gave the corresponding metal-complexes which were characterised by spectroscopic methods
Spectroscopic investigation on 1,2-substituted ferrocenes with only planar chirality: how chiroptical data are related to absolute configuration and to substituents
Single enantiomers of three 1,2-substituted ferrocene derivatives, i.e. 1-methoxymethyl-2-hydroxyme
thylferrocene (1), 1-formyl-2-hydroxymethylferrocene (2) and 1-iodo-2-hydroxymethylferrocene (3),
sharing the common hydroxymethyl substituent and the presence of planar chirality only, were investigated
for their spectroscopic (IR and UV) and chiroptical (VCD and ECD) properties. Both enantiomers of 1
were obtained for the first time in optically pure form by lipase-catalyzed kinetic resolution of the corresponding
racemate (±)-1 and separately converted into formyl derivatives (+)-2 and (–)-2.
The experimental spectroscopic and chiroptical data were compared with DFT calculated spectra and
excellent correspondence was found for all compounds, allowing one to confirm the previously assigned
absolute configurations. The common features in the VCD spectra of a doublet between 940 and 965 cm1
and the short-wavelength (about 200 nm) doublet and the longest wavelength band in the ECD spectra
were analyzed to test whether they may be taken as markers of the absolute configuration (AC). The predominance
of conformers with intramolecular hydrogen bond for the first two investigated compounds is
predicted by conformational analysis and also confirmed by NMR
Ferrocenes with simple chiral substituents: an in-depth theoretical and experimental VCD and ECD study
Circular dichroism spectra in the IR range (VCD = vibrational circular dichroism) and in the UV range (ECD = electronic circular dichroism) have been recorded for both enantiomers of simple mono-substituted ferrocenes containing chiral pendants: 1-acetoxyethylferrocene, 1, 1-methoxyethylferrocene, 2, and 1-hydroxyethylferrocene, 3; the related disubstituted 1,1'-bis(1-hydroxyethyl)ferrocene, 4, was also considered. These two types of spectra, with the support of DFT calculations, concur to unequivocally confirm the absolute configuration for 1-4. In particular, our computational results point out the clear advantage of using an anharmonic oscillator model for the interpretation of VCD spectra of chiral ferrocenes. Interesting conformational properties are either confirmed or established by the technique, like the eclipsed conformation of the two cyclopentadienyl rings and an intra-molecular interaction involving the OH for 3. For 4, NMR, VCD and IR spectra are compatible with dimer formation and in this case a distorted conformation is predicted. Of utmost importance for the absolute configuration assignment in mono-substituted ferrocenes, we were able to identify a diagnostic VCD band at 950 cm-1 and a (low intensity) ECD band that clearly indicate the absolute configuration of the whole series