Effect of CYP3A4, CYP3A5, MDR1 and POR Genetic Polymorphisms in Immunosuppressive Treatment in Chilean Kidney Transplanted Patients

Cyclosporine (CsA) and tacrolimus (TAC) are immunosuppressant drugs characterized by a narrow therapeutic range and high pharmacokinetic variability. The effect of polymorphisms in genes related to the metabolism and transport of these drugs, namely CYP3A4, CYP3A5, MDR1 and POR genes, has been evaluated in diverse populations. However, the impact of these polymorphisms on drug disposition is not well established in Latin American populations. Using TaqMan® probes, we determined the allelic frequency of seven variants in CYP3A4, CYP3A5, MDR1 and POR in 139 Chilean renal transplant recipients, of which 89 were treated with CsA and 50 with TAC. We tested associations between variants and trough and/or 2-hour concentrations, normalized by dose (C₀/D and C₂/D) at specific time points post-transplant. We found that CYP3A5*3/*3 carriers required lower doses of TAC. In TAC treated patients, most CYP3A5*3/*3 carriers presented higher C₀/D and a high proportion of patients with C₀ levels outside the therapeutic range relative to other genotypes. These results reinforce the value of considering CYP3A5 genotypes alongside therapeutic drug monitoring for TAC treated Chilean kidney recipients.

Synthetic Approaches to Phosphasugars (2-oxo-1,2-oxaphosphacyclanes) Using the Anomeric Alkoxyl Radical β-Fragmentation Reaction as the Key Step

The anomeric alkoxyl radical β-fragmentation (ARF) of carbohydrates possessing an electron-withdrawing group (EWG) at C2, promoted by PhI(OAc)₂/I₂, gives rise to an acyclic iodide through which a pentavalent atom of phosphorus can be introduced via the Arbuzov reaction. After selective hydrolysis and subsequent cyclization, the phosphonate or phosphinate intermediates can be converted into 2-deoxy-1-phosphahexopyranose and 2-deoxy-1-phosphapentopyranose sugars. The ARF of carbohydrates with an electron-donor group (EDG) at C2 proceeds by a radical-polar crossover mechanism, and the cyclization occurs by nucleophilic attack of a conveniently positioned phosphonate or phosphinate group to the transient oxocarbenium ion. This alternative methodology leads to 5-phosphasugars with a 4-deoxy-5-phosphapentopyranose framework. The structure and conformation of the 2-oxo-1,2-oxaphosphinane and 2-oxo-1,2-oxaphospholane ring systems in different carbohydrate models have been studied by NMR and X-ray crystallography.

Activation of aryl hydrocarbon receptor regulates the LPS/IFNγ-induced inflammatory response by inducing ubiquitin-proteosomal and lysosomal degradation of RelA/p65

Several studies have identified the aryl hydrocarbon receptor (AhR) as a negative regulator of the innate and adaptive immune responses. However, the molecular mechanisms by which this transcription factor exerts such modulatory effects are not well understood. Interaction between AhR and RelA/p65 has previously been reported. RelA/p65 is the major NFκB subunit that plays a critical role in immune responses to infection. The aim of the present study was to determine whether the activation of AhR disrupted RelA/p65 signaling in mouse peritoneal macrophages by decreasing its half-life. The data demonstrate that the activation of AhR by TCDD and β-naphthoflavone (β-NF) decreased protein levels of the pro-inflammatory cytokines TNF-α, IL-6 and IL-12 after macrophage activation with LPS/IFNγ. In an AhR-dependent manner, TCDD treatment induces RelA/p65 ubiquitination and proteosomal degradation, an effect dependent on AhR transcriptional activity. Activation of AhR also induced lysosome-like membrane structure formation in mouse peritoneal macrophages and RelA/p65 lysosome-dependent degradation. In conclusion, these results demonstrate that AhR activation promotes RelA/p65 protein degradation through the ubiquitin proteasome system, as well as through the lysosomes, resulting in decreased pro-inflammatory cytokine levels in mouse peritoneal macrophages.

SUMOylation regulates AKT1 activity

Serine threonine kinase AKT has a central role in the cell, controlling survival, proliferation, metabolism and angiogenesis. Deregulation of its activity underlies a wide range of pathological situations, including cancer. Here we show that AKT is post-translationally modified by the small ubiquitin-like modifier (SUMO) protein. Interestingly, neither SUMO conjugation nor activation of SUMOylated AKT is regulated by the classical AKT targeting to the cell membrane or by the phosphoinositide 3-kinase pathway. We demonstrate that SUMO induces the activation of AKT, whereas, conversely, down-modulation of the SUMO machinery diminishes AKT activation and cell proliferation. Furthermore, an AKT SUMOylation mutant shows reduced activation, and decreased anti-apoptotic and pro-tumoral activities in comparison with the wild-type protein. These results identify SUMO as a novel key regulator of AKT phosphorylation and activity.

Regulation of the tumor suppressor PTEN by SUMO

The crucial function of the PTEN tumor suppressor in multiple cellular processes suggests that its activity must be tightly controlled. Both, membrane association and a variety of post-translational modifications, such as acetylation, phosphorylation, and mono- and polyubiquitination, have been reported to regulate PTEN activity. Here, we demonstrated that PTEN is also post-translationally modified by the small ubiquitin-like proteins, small ubiquitin-related modifier 1 (SUMO1) and SUMO2. We identified lysine residue 266 and the major monoubiquitination site 289, both located within the C2 domain required for PTEN membrane association, as SUMO acceptors in PTEN. We demonstrated the existence of a crosstalk between PTEN SUMOylation and ubiquitination, with PTEN-SUMO1 showing a reduced capacity to form covalent interactions with monoubiquitin and accumulation of PTEN-SUMO2 conjugates after inhibition of the proteasome. Moreover, we found that virus infection induces PTEN SUMOylation and favors PTEN localization at the cell membrane. Finally, we demonstrated that SUMOylation contributes to the control of virus infection by PTEN.

Sediment and pollutant load modelling using an integrated urban drainage modelling toolbox: an application of City Drain

Numerical and computational modelling of flow and pollutant dynamics in urban drainage systems is becoming more and more integral to planning and design. The main aim of integrated flow and pollutant models is to quantify the efficiency of different measures at reducing the amount of pollutants discharged into receiving water bodies and minimise the consequent negative water quality impact. The open source toolbox CITY DRAIN developed in the Matlab/Simulink environment, which was designed for integrated modelling of urban drainage systems, is used in this work. The goal in this study was to implement and test computational routines for representing sediment and pollutant loads in order to evaluate catchment surface pollution. Tested models estimate the accumulation, erosion and transport of pollutants--aggregately--on urban surfaces and in sewers. The toolbox now includes mathematical formulations for accumulation of pollutants during dry weather period and their wash-off during rainfall events. The experimental data acquired in a previous research project carried out by the Environmental Engineering Research Centre (CIIA) at the Universidad de los Andes in Bogotá (Colombia) was used for the calibration of the models. Different numerical approaches were tested for their ability to calibrate to the sediment transport conditions. Initial results indicate, when there is more than one peak during the rainfall event duration, wash-off processes probably can be better represented using a model based on the flow instead of the rainfall intensity. Additionally, it was observed that using more detailed models (compared with an instantaneous approach) for representing pollutant accumulation do not necessarily lead to better results.

[Individual differences in hypothetic-deductive reasoning: importance of cognitive skills and flexibility]

Recent investigations show that people's differential performance when solving reasoning tasks is due to differences not only at computational level, but also at the rational or intentional level. This study is within the framework of this context and it specifically analyses individual differences in hypothetic-deductive reasoning, taking into account the characteristics associated with the task itself (content and instructions) as well as the individuals' differential characteristics. Two hundred and seventy-six students from the University of Santiago de Compostela participated in this study. Several psychometric tests were administered and participants were requested to solve various reasoning tasks. The results obtained confirm that, in effect, the differences between competent and non-competent reasoners are observed at both the above-mentioned levels: cognitive skills and abilities (algorithmic level) and cognitive flexibility (intentional level).

Fragmentation of carbohydrate anomeric alkoxyl radicals. A new synthesis of chiral beta-iodo azides, vinyl azides, and 2H-azirines

[reaction: see text] The reaction of 3-azido-2,3-dideoxy-hexopyranose compounds from the d-gluco, d-galacto, d-lacto, and l-arabino carbohydrate series, with (diacetoxyiodo)benzene and iodine, generated 2-azido-1,2-dideoxy-1-iodo-alditols with one carbon less than the starting carbohydrate. These beta-iodo azides could be transformed by dehydroiodination into vinyl azides, which in turn afforded 3-monosubstituted 2H-azirines under thermal conditions. These beta-iodo azides and 2H-azirines may be interesting chiral synthons for the preparation of more complex heterocyclic systems.

Synthesis of phytuberin. 4-endo-tet acid-catalyzed cyclization of alpha-hydroxy epoxides

The total synthesis of phytuberin, a phytoalexin of the Solanum genus, from (-)-alpha-santonin is reported. The key steps include (a) reductive cleavage of the C-O bond of the gamma-lactone with concomitant protection of the C1 double bond, (b) Sharpless stereocontrolled hydroxy-assisted epoxidation of allylic alcohol 6 and simultaneous deprotection of the C1 double bond, (c) a rare 4-endo-tet acid-catalyzed cyclization of an alpha-hydroxy epoxide, and (d) an unprecedented 4-exo selenocyclization of a homoallylic alcohol.

Retention of granular sludge at high hydraulic loading rates in an anaerobic membrane bioreactor with immersed filtration

This study shows the results of an Anaerobic Membrane Bioreactor with immersed filtration cartridges for granular biomass retention working at high hydraulic loading rates. Biomass retention capabilities, granular biomass structure and activity, filtration cartridges flux and organic material degradation performance were evaluated. Four reactors with a volume of 0.005 m3 were tested. Two different filtration cartridges were used (10 and 100 microm) with effective surface area of 0.05 m2. The filtration cartridges were submerged in the reactors for suction type filtration. Three organic loading rates were tested in the first two reactors and seven in the other two. Selective biomass washout and an increment in the biomass methanogenic activity was observed in the reactors at hydraulic loading rates between 1.2 and 4.5 m/h. Analyses of biomass granulometry showed an increase of larger size granular biomass. The immersed membrane anaerobic bioreactor maintain most of the advantages without biomass activity loss.

Reductive fragmentation of carbohydrate anomeric alkoxy radicals. Synthesis of alditols with potential utility as chiral synthons

A series of anomeric nitrate esters and N-phthalimido glycosides of carbohydrates in furanose and pyranose forms have been synthesized in order to generate the corresponding alkoxy radicals and study the C1-C2 fragmentation reaction under reductive conditions. This reaction constitutes a two-step method for the transformation of carbohydrates into the corresponding alditols with one less carbon. Using this methodology, interesting four- and five-carbon building blocks for natural products synthesis possessing D-erythritol, D-threitol, D-xylitol, and D-arabinitol stereochemistry have been prepared. The synthesis of 1,2-O-isopropylidene-beta-L-threose (40) and 1-acetamido-2,4,5-tri-O-acetyl-D-arabinitol (50) have also been achieved from 1,2:5,6-di-O-isopropylidene-beta-D-glucofuranose and 2-acetamido-3,4,6-tri-O-acetyl-2-deoxy-D-glucopyranose, respectively.

Tandem beta-Fragmentation-Hydrogen Abstraction Reaction of Alkoxy Radicals in Steroidal Systems

A number of tertiary or hemiacetalic steroidal alcohols, 2-hydroxy-3,4-dinor-2,3-secocholestan-5-one 2,5-hemiacetal (1), 2beta,3beta-dihydro-3'H-cyclopropa[2,3]-cholestan-5alpha-ol (7), 3beta-phenyl-5alpha-hydroxycholestan-2-one (10), 5alpha-hydroxycholestan-3-one (15), 3beta,5alpha-dihydroxycholestan-7-one 3-acetate (21), and 4,4-dimethyl-19-hydroxy-5alpha-cholestan-3-one 19,3-hemiacetal (27) have been prepared in order to test a new tandem beta-fragmentation-hydrogen abstraction reaction. The alkoxy radicals generated by irradiation of these alcohols with visible light in the presence of (diacetoxyiodo)benzene, iodine, and molecular oxygen undergo a beta-fragmentation reaction followed by peroxidation of the C-radical formed. The peroxy radical reacts further with iodine to give an alkoxy radical and iodoxyl radical (IO(*)). The new alkoxy radical can produce intramolecular functionalization of suitably positioned carbons by hydrogen abstraction through a six-membered cyclic transition state to give tetrahydrofurans or can be intramolecularly trapped by carbonyl groups suitably disposed so as to generate a new alkoxy radical that can afford gamma-lactones by beta-fragmentation.

[Clinical and anatomopathological study of 5 patients with vasculitis and anti-neutrophil cytoplasmic antibodies with cytoplasmatic pattern]

We report five patients with vasculitis and antineutrophil cytoplasmic antibodies with cytoplasmatic pattern. All had severe upper and lower respiratory tract necrotizing lesions. Three had kidney failure due to rapidly progressive glomerulonephritis. The pathological study showed a crescentic glomerulonephritis, a chronic granulomatous inflammation in the lungs and in the nasal mucosa, an acute nonspecific inflammation or a chronic granulomatous inflammation and focal blood vessel fibrinoid necrosis. All patients with simultaneous involvement of lungs and kidneys had high titers of antineutrophil cytoplasmic antibodies. The nomenclature and classification of these diseases is discussed.

The use of the STRs HUMTH01, HUMVWA31/A, HUMF13A1, HUMFES/FPS, HUMLPL in forensic application: validation studies and population data for Galicia (NW Spain)

The 5 tetranucleotide short tandem repeats, HUMTH01, HUMVWA31/A, HUMF13A1, HUMFES/FPS and HUMLPL were studied using different electrophoretic methods and PCR amplification conditions in order to optimize the typing conditions. A genetic population study in the population of Galicia was carried out and the allele and genotype frequencies are given. Compliance with the Hardy-Weinberg equilibrium was tested using different statistical parameters, with clear advantages resulting in favor of using the exact test (Guo-Thompson method) instead of conventional chi-square methods. Some statistical parameters of forensic interest (PD, CE, h) were also calculated. There were no mutations found in a total of 73 paternal meioses and 101 maternal meioses. Abnormal electrophoretic mobility was found in the AT-rich STR HUMF13A1 under non-denaturing conditions and, therefore, the use of denaturing conditions is absolutely necessary. No "stutter" bands were found, although double peaks in the HUMFES/FPS system were observed in some samples. The advantage of using automated sequencers with fluorescent technology is also reported.

Semiquinones derived from anthraquinone-containing antitumor drugs can partition into phosphatidylcholine bilayers

Semiquinones derived from anthraquinone-containing antitumor drugs (doxorubicin, daunorubicin and 4'-epidoxorubicin) were generated by the hypoxanthine/xanthine oxidase system in argon-saturated phosphate buffer (pH 7.4) in the presence of egg-yolk phosphatidylcholine multilamellar vesicles (MLVs) containing 1 mol% of a doxylstearic acid (DSA) isomer. The destruction of the electron spin resonance signal corresponding to 5-, 12- and 15-DSA included in the MLVs follows pseudo-first-order kinetics. Higher rates of destruction are obtained for the 12-DSA isomer which indicates that these semiquinones can localize preferentially about the depth of the 12th position of stearic acid in membranes. It is demonstrated that DSA destruction is due to a reversible reduction of DSA to the hydroxylamine species. This work shows that anthracycline semiquinones can partition into phosphatidylcholine bilayers under anoxic conditions which may imply another pathway in their cytotoxic action.

[Risk factors of cardiovascular disease in a Chilean school population: I: Blood lipids in 552 children and adolescents 6-15 years of age]

The distribution of serum cholesterol (TC), low density lipoprotein (LDL) cholesterol, high density lipoprotein (HDL)-cholesterol and triglycerides (TG), and the prevalence of risk-considered values were studied in school children from Concepción, Chile (6 to 15 years old; 326 boys, 226 girls). The mean TC levels were 146 mg/dl for boys and 154 mg/dl for girls but 9.1% of the sampled children had TC values between 175 and 190 mg/dl, and 10% were over 190 mg/dl. Mean LDL-C was 83 mg/dl in boys and 89 mg/dl in girls; 6% of samples showed values between 130 and 159 mg/dl, and 1.3% over 160 mg/dl. Mean HDL-C was 46 mg/dl for boys and 48 mg/dl for girls. The mean TG values were 80 mg/dl for boys and 93 mg/dl for girls.

[Enalapril in essential arterial hypertension]

The hypotensive effect of enalapril, a converting enzyme inhibitor, given as a single agent once daily, was evaluated prospectively over a 16 week period in 20 subjects. One patient abandoned therapy and 2 were withdrawn (increased creatinine levels in one and the need for associated therapy in the other). Side effects developed in 3 patients: creatinine elevation, skin rush and a "salty taste", respectively. A significant decrease in blood pressure (p less than 0.01) attaining normal levels in 6 out of 17 patients was observed. Normal blood pressure levels were not reached in severe hypertension; the association of hydrochlorothyazide was effective in 5 of 11 such subjects. Thus, enalapril may be safely used as a first stage single therapy in mild or moderate hypertension.

[Correlation of clinical, radiologic and pathologic aspects of the thymus in newborn infants]

The thymus of 30 autopsied neonates who died from different causes (hyaline membrane disease: 13 cases; severe infections: 11 cases; congenital malformations: 4 cases; severe asphyxia: 2 cases) were prospectively examined in order to look for the most frequent macroscopic and microscopic morphological changes in this organ. Findings were correlated with clinical and radiological data. In hyaline membrane disease patients moderate decrease of thymic weight and slight depletion of cortical lymphocytes as to reference values were observed; such changes were likewise seen in cases with malformations and severe asphyxia. Newborns who died from severe infections exhibited early and pronounced decrease of thymic weight as well as severe depletion of cortical lymphocytes, more noticeable at all times than in the remaining groups. It is concluded that the predominant finding in examined patients is thymic involution secondary to stress, whose intensity would depend upon the type and duration of the main disease, being most severe the longer the evolutionary time. The variability observed in thymic size of individuals with similar physical features and the lack of an accurate correlation between radiology and post mortem findings with respect to thymic size are remarkable.

[Correction of facial disharmony using mandibular bone grafts]

The case of a patient affected by maxillary retrognathism associated with mandibular prognathism, is described. The patient was operated in our service after being studied in the multidisciplinary clinics. It is determined to use a mandibular bone graft in order to make use of the same surgical area, avoiding, in that way, maxillary retrodisplacement and additional aggressions to the patients, which should be caused by the act of taking a fragment of the crest of the iliac bone. The patient presents a wholly favorable evolution.