Decentralization Can Improve Equity, but Can It Be Sustained?

A major theoretical issue about health system reform involving decentralization has been whether it promotes equity of health system funding. An article by the principal author and others in 2003 showed that, under certain conditions and policies, decentralization improved the equity of allocation of financial resources to different income levels of municipalities in Colombia and Chile. Another recurring issue has been whether reforms can be sustained over time. In a follow-up study in 2015, we found that the equity of national allocations was sustained even though the allocation rules for intergovernmental transfers and insurance funding sources had changed, as long as per capita allocation rules were retained. Nevertheless, the wealthier municipalities in Chile were able to increase their own source funding contributing to a larger gap between wealthy and poor municipalities, suggesting that in order to assure continued equity some compensation for these funds be included in intergovernmental transfer rules or that local source funding be restricted by national policy. These reforms may be more likely to be sustained if they become embedded in existing financial systems and if they receive support of status quo constituencies.

[Evaluation dosing intravenous voriconazole three times a day vs twice daily for the treatment of invasive aspergillosis in immunocompromised children: therapeutic drugs monitoring and safety]. / Evaluación de la dosificación de voriconazol intravenoso tres veces al día vs dos veces al día para el tratamiento de aspergilosis invasora en niños inmunocomprometidos: monitorización terapéutica y seguridad.

BACKGROUND: Voriconazole is the antifungal of choice for the treatment of invasive aspergillosis (IA). Plasma concentrations (PCs) > 1 µg / mL llave been associated with better therapeutic results which have not always been achieved during treatment in immunocompromised children. In the necessity to initiate early and effective therapy for the infection, it is relevant to establish the voriconazole administration regimen that is associated with optimal PCs in this population. AIM: To compare the PC and safety of intravenous (IV) voriconazole, dosed BID and TID in immunocompromised children with indication of antifungal treatment. METHOD: Retrospective observational study since January 2015 until July 2018 in a highly complex pediatric hospital in Santiago of Chile, in patients aged 0 to 17 years who received treatment with IV voriconazole. Those with renal replacement therapy, liver failure and / or renal failure were excluded. Trough PCs were compared between a group with BID dosing regimen versus another group with TID administration. Adverse reactions were evaluated in both groups. RESULTS: 137 trough PCs were obtained in 76 children, with a median age of 9 years (0-17 years) in the BID group and 9 years (0-16) in the TID group with a median weight of 27 kg (6-83 kg) and 28 kg (9.3-60 kg), respectively. Patients < 12 years old exposed to TID dosages are 4.65 times (OR: 4.65, 95% CI 1.93-11.2) more likely to have PC > 1 gg/mL compared to BID administration (p = 0.001). Eight adverse reactions were reported, mainly photophobia, with no significant difference found between the BID and TID groups. CONCLUSION: TID dosages are associated with a greater probability of obtaining adequate exposure to voriconazole in patients < 12 years old compared to BID dosages, with a low frequency of adverse reactions.

Evaluación de la dosificación de voriconazol intravenoso tres veces al día vs dos veces al día para el tratamiento de aspergilosis invasora en niños inmunocomprometidos: monitorización terapéutica y seguridad / Evaluation dosing intravenous voriconazole three times a day vs twice daily for the treatment of invasive aspergillosis in immunocompromised children: therapeutic drugs monitoring and safety

INTRODUCCIÓN: Voriconazol es el antifúngico de elección para el tratamiento de la aspergilosis invasora (AI). Concentraciones plasmáticas (CPs) > 1 μg/mL se han asociado a mejores resultados terapéuticos, las que no siempre se alcanzan durante el tratamiento en niños inmunocomprometidos. Dada la necesidad de iniciar una terapia precoz y efectiva de la infección, es relevante establecer el régimen de administración de voriconazol que se asocie con CPs óptimas en esta población. OBJETIVO: Comparar las CPs y seguridad de voriconazol intravenoso (IV), dosificado BID y TID en niños inmunocomprometidos con indicación de tratamiento antifúngico. MÉTODO: Estudio observacional retrospectivo de enero de 2015 a julio de 2018 en un hospital pediátrico de alta complejidad de Santiago de Chile, en pacientes de 0 a 17 años que recibieron tratamiento con voriconazol IV. Se excluyeron aquellos con terapia de reemplazo renal, falla hepática y/o falla renal. Se compararon las CPs valles entre un grupo con régimen de dosificación BID y otro grupo con administración TID. Se evaluaron las reacciones adversas en ambos grupos. RESULTADOS: Se obtuvieron 137 CPs valles en 76 niños, con una mediana de edad de 9 años (0-17 años) en el grupo BID y 9 años (0-16 años) en el grupo TID, con una mediana de peso de 27 kg (6-83 kg) y 28 kg (9,3-60 kg), respectivamente. Resultados: Pacientes 1 gg/mL en comparación con la administración BID (p = 0,001). Se reportaron ocho reacciones adversas, principalmente fotofobia, sin encontrarse diferencias significativas entre grupo BID y TID. CONCLUSIÓN: Dosificaciones TID están asociadas a una mayor probabilidad de obtener una adecuada exposición a voriconazol en pacientes < 12 años en comparación a dosificaciones BID, con baja frecuencia de reacciones adversas.

BACKGROUND: Voriconazole is the antifungal of choice for the treatment of invasive aspergillosis (IA). Plasma concentrations (PCs) > 1 μg / mL llave been associated with better therapeutic results which have not always been achieved during treatment in immunocompromised children. In the necessity to initiate early and effective therapy for the infection, it is relevant to establish the voriconazole administration regimen that is associated with optimal PCs in this population. AIM: To compare the PC and safety of intravenous (IV) voriconazole, dosed BID and TID in immunocompromised children with indication of antifungal treatment. METHOD: Retrospective observational study since January 2015 until July 2018 in a highly complex pediatric hospital in Santiago of Chile, in patients aged 0 to 17 years who received treatment with IV voriconazole. Those with renal replacement therapy, liver failure and / or renal failure were excluded. Trough PCs were compared between a group with BID dosing regimen versus another group with TID administration. Adverse reactions were evaluated in both groups. RESULTS: 137 trough PCs were obtained in 76 children, with a median age of 9 years (0-17 years) in the BID group and 9 years (0-16) in the TID group with a median weight of 27 kg (6-83 kg) and 28 kg (9.3-60 kg), respectively. Patients 1 gg/mL compared to BID administration (p = 0.001). Eight adverse reactions were reported, mainly photophobia, with no significant difference found between the BID and TID groups. CONCLUSION: TID dosages are associated with a greater probability of obtaining adequate exposure to voriconazole in patients < 12 years old compared to BID dosages, with a low frequency of adverse reactions.

Green and facile sol-gel synthesis of the mesoporous SiO2-TiO2 catalyst by four different activation modes.

The most environmentally friendly protocol for obtaining mesoporous SiO2-TiO2 catalysts has been sought. Water has been employed as a green solvent, the energy input has been minimized, and three further principles (1, 3, and 12) of Green Chemistry have been considered. Four different modes for promoting the reaction have been comparatively evaluated, namely near-infrared and microwave electromagnetic irradiations, ultrasound, and traditional mantle heating. Brunauer-Emmett-Teller (BET) analyses of the catalysts produced revealed that the non-conventional activation modes afforded both large surface areas (335-441 m2 g-1) and smaller crystal sizes (7.2-15.3 nm) than the mantle heating process. These modes also generated the catalysts in shorter reaction times than traditional mantle heating, 10-30 min versus 3 h, with anatase as the sole crystalline phase. The photocatalytic degradation of 4-chlorophenol has been carried out to assess the catalytic efficiencies of the hybrid materials. The catalyst synthesized with microwave assistance showed the best mineralization activity (97%), followed by those prepared with ultrasound, near-infrared, and mantle heating. The materials have been extensively characterized by FTIR, XRD, DRS-UV/Vis, SEM, 29Si MAS NMR, and BET analyses. To the best of our knowledge, this is the first such comparative assessment of green energetic alternatives in developing a sol-gel process.

[Drug related harm in Chilean hospitals: prevalence analysis 2010-2017]. / Daño asociado al uso de medicamentos en hospitales chilenos: análisis de prevalencia 2010-2017.

BACKGROUND: Medication related adverse events are an important cause of hospital admission or prolonged stay. AIM: To assess medication related adverse events in a hospital discharge database. MATERIAL AND METHODS: Revision of the Chilean hospital discharge database from 2010 to 2017 searching for ICD- 10 diagnostic codes corresponding to medication related adverse events. RESULTS: The number of medication related adverse events was stable across the studied time lapse, but admission length increased. Between 34 and 111 people died every year due to medication related adverse events. Lactating babies, toddlers, adolescents and people over 80 years of age are at greater risk of experiencing these events. CONCLUSIONS: Medication related adverse events are more common than expected.

Daño asociado al uso de medicamentos en hospitales chilenos: análisis de prevalencia 2010-2017 / Drug related harm in Chilean hospitals: prevalence analysis 2010-2017

Background: Medication related adverse events are an important cause of hospital admission or prolonged stay. Aim: To assess medication related adverse events in a hospital discharge database. Material and Methods: Revision of the Chilean hospital discharge database from 2010 to 2017 searching for ICD- 10 diagnostic codes corresponding to medication related adverse events. Results: The number of medication related adverse events was stable across the studied time lapse, but admission length increased. Between 34 and 111 people died every year due to medication related adverse events. Lactating babies, toddlers, adolescents and people over 80 years of age are at greater risk of experiencing these events. Conclusions: Medication related adverse events are more common than expected.

Alternative mass spectrometry techniques for the validation of the fragmentation pattern of capsaicin and dihydrocapsaicin.

RATIONALE: Capsaicinoids are prevalent secondary metabolites in many natural and synthetic pharmacological compounds. To date, several soft ionization studies related to capsaicinoids have been reported; they all proposed a common fragmentation pattern based on a rearrangement of the aromatic double bonds and the fragmentation of the various positional acyl chains. However, the mechanism has never been validated by high-resolution analyses. Consequently, in this work, a validated fragmentation mechanism of the main capsaicinoids, capsaicin (1) and dihydrocapsaicin (2), is offered. METHODS: In order to propose and validate a common electron ionization (EI) fragmentation mechanism for the target analytes, the following mass spectrometric methods were employed: collision-induced dissociation (CID) by means of linked scans (LS), reinforcing the methodology by high-resolution mass spectrometry (HRMS), in addition to appropriate deuterium-labeled experiments performed using gas chromatography/mass spectrometry (GC/MS) and direct analysis in real time (DART). RESULTS: In a first stage, a common EI fragmentation pattern comprising two pathways was proposed for compounds 1 and 2; then, the suggested mechanism was validated by CID-LS together with HRMS complemented by DART-deuterium-labeling studies. The obtained results are indicative that the corresponding molecular ions were conveniently observed, m/z 305 and m/z 307; it is worth noting that the common base peak is in correspondence with a tropylium ion derivative (m/z 137), as a consequence of a McLafferty rearrangement. In addition to these highlighted fragments, other common ions, m/z 122 and m/z 94, and their corresponding trajectory, were confirmed using the same approach. Finally, the proposed mechanism was complementarily validated by deuterium-labeling studies, taking into account the two exchangeable hydrogens present in the phenolic and the amidic moieties. CONCLUSIONS: A common validated EI fragmentation pattern for both capsaicin and dihydrocapsaicin was established using appropriated mass spectrometric methods together with convenient hydrogen/deuterium labeling. This study provides a new alternative to validate mechanisms of fragmentation of important natural products.

Infrared Irradiation: Toward Green Chemistry, a Review.

This review provides a comprehensive overview of where infrared irradiation has been employed, mainly as regards activating green mode for natural products extractions, as well as to favor a reaction, highlighting its actual importance. It is also underlined that infrared irradiation heating has been around for a long time; however, only in the last eighteen years have many of its advantages been applied to satisfy a wide range of chemical processes, natural products extractions, and for the promotion of many kinds of reactions. In addition, it is brought to light that near infrared irradiation is more efficient than middle and far infrared irradiations, being easily controllable and with the quality of a fast responding heat source. Thus, the main objective of this review is to offer infrared irradiation as an alternative clean energy source to activate reactions, in addition to favor the selective extraction of natural products, all of which is within the Green Chemistry protocol. Some recent results from our laboratory are also included.

QSAR, docking, dynamic simulation and quantum mechanics studies to explore the recognition properties of cholinesterase binding sites.

A set of 84 known N-aryl-monosubstituted derivatives (42 amides: series 1 and 2, and 42 imides: series 3 an 4, from maleic and succinic anhydrides, respectively) that display inhibitory activity toward both acetylcholinesterase and butyrylcholinesterase (ChEs) was considered for Quantitative structure-activity relationship (QSAR) studies. These QSAR studies employed docking data from both ChEs that were previously submitted to molecular dynamics (MD) simulations. Donepezil and galanthamine stereoisomers were included to analyze their quantum mechanics properties and for validating the docking procedure. Quantum parameters such as frontier orbital energies, dipole moment, molecular volume, atomic charges, bond length and reactivity parameters were measured, as well as partition coefficients, molar refractivity and polarizability were also analyzed. In order to evaluate the obtained equations, four compounds: 1a (4-oxo-4-(phenylamino)butanoic acid), 2a ((2Z)-4-oxo-4-(phenylamino)but-2-enoic acid), 3a (2-phenylcyclopentane-1,3-dione) and 4a (2-phenylcyclopent-4-ene-1,3-dione) were employed as independent data set, using only equations with r(m(test))²>0.5. It was observed that residual values gave low value in almost all series, excepting in series 1 for compounds 3a and 4a, and in series 4 for compounds 1a, 2a and 3a, giving a low value for 4a. Consequently, equations seems to be specific according to the structure of the evaluated compound, that means, series 1 fits better for compound 1a, series 3 or 4 fits better for compounds 3a or 4a. Same behavior was observed in the butyrylcholinesterase (BChE). Therefore, obtained equations in this QSAR study could be employed to calculate the inhibition constant (Ki) value for compounds having a similar structure as N-aryl derivatives described here. The QSAR study showed that bond lengths, molecular electrostatic potential and frontier orbital energies are important in both ChE targets. Docking studies revealed that despite the multiple conformations obtained through MD simulations on both ChEs, the ligand recognition properties were conserved. In fact, the complex formed between ChEs and the best N-aryl compound reproduced the binding mode experimentally reported, where the ligand was coupled into the choline-binding site and stabilized through π-π interactions with Trp82 or Trp86 for BChE and AChE, respectively, suggesting that this compound could be an efficient inhibitor and supporting our model.

Synthesis of cycloveratrylene macrocycles and benzyl oligomers catalysed by bentonite under microwave/infrared and solvent-free conditions.

Tonsil Actisil FF, which is a commercial bentonitic clay, promotes the formation of cycloveratrylene macrocycles and benzyl oligomers from the corresponding benzyl alcohols in good yields under microwave heating and infrared irradiation in the absence of solvent in both cases. The catalytic reaction is sensitive to the type of substituent on the aromatic ring. Thus, when benzyl alcohol was substituted with a methylenedioxy, two methoxy or three methoxy groups, a cyclooligomerisation process was induced. Unsubstituted, methyl and methoxy benzyl alcohols yielded linear oligomers. In addition, computational chemistry calculations were performed to establish a validated mechanistic pathway to explain the growth of the obtained linear oligomers.

DFT and docking studies of rhodostreptomycins A and B and their interactions with solvated/nonsolvated Mg²âº and Ca²âº ions.

The interactions of L-aminoglucosidic stereoisomers such as rhodostreptomycins A (Rho A) and B (Rho B) with cations (Mg(2+), Ca(2+), and H(+)) were studied by a quantum mechanical method that utilized DFT with B3LYP/6-311G. Docking studies were also carried out in order to explore the surface recognition properties of L-aminoglucoside with respect to Mg(2+) and Ca(2+) ions under solvated and nonsolvated conditions. Although both of the stereoisomers possess similar physicochemical/antibiotic properties against Helicobacter pylori, the thermochemical values for these complexes showed that its high affinity for Mg(2+) cations caused the hydration of Rho B. According to the results of the calculations, for Rho A-Ca(2+)(H2O)6, ΔH = -72.21 kcal mol(-1); for Rho B-Ca(2+)(H2O)6, ΔH = -72.53 kcal mol(-1); for Rho A-Mg(2+)(H2O)6, ΔH = -72.99 kcal mol(-1) and for Rho B-Mg(2+)(H2O)6, ΔH = -95.00 kcal mol(-1), confirming that Rho B binds most strongly with hydrated Mg(2+), considering the energy associated with this binding process. This result suggests that Rho B forms a more stable complex than its isomer does with magnesium ion. Docking results show that both of these rhodostreptomycin molecules bind to solvated Ca(2+) or Mg(2+) through hydrogen bonding. Finally, Rho B is more stable than Rho A when protonation occurs.

Thioglycerol matrix interactions in the positive ion fast atom bombardment mass spectrometry of several Hantzsch and Biginelli ester derivatives of boronic acids.

RATIONALE: Fast atom bombardment (FAB) ionization is a valuable tool for analyzing non-volatile or thermally labile compounds when harder ionization methods (EI or CI) have been unsuccessful. Unexpected interactions between matrix and analyte may, however, occur in FAB ionization leading to the formation of artifacts whose structures have to be determined. METHODS: We used esters synthesized by our research group following green chemistry protocols. Artifacts relating to the target molecules were produced in the solvent cage using positive ion FAB using thioglycerol as the matrix and analyzed by accurate mass measurement. RESULTS: Through interactions between thioglycerol and the boron atom, various adducts associated with boron-containing Hantzsch and Biginelli ester derivatives appeared in the FAB mass spectra. These interactions must arise in a solvent cage involving a Lewis acid-base bond. Accurate mass determinations of these adducts confirmed the presence of the target molecules. CONCLUSIONS: Interactions between the thioglycerol matrix and the eleven boron-containing Hantzsch and Biginelli ester derivatives in addition to the three reagents were seen in their FAB(+) spectra. These interactions, together with their accurate mass determinations, allowed us to determine the structures of the new molecules.

Pseudoaneurisma e CIV pós-IAM concomitantes: apresentação grave e rara / Pseudoaneurysm and VSD concomitant after AMI: severe and rare presentation

Relata-se caso raro de dupla-complicação mecânicapós-IAM anterior: pseudoaneurisma e comunicação interventricular (CIV). Paciente do sexo feminino,66 anos, tendo apresentado quadro de dor torácica típica, foi submetida à cineangiocoronariografia, que demonstrou oclusão total em terço médio de artéria descendente anterior (DA), com angioplastia realizada10 dias após o início do quadro. Evoluiu após três semanas com recidiva de dor precordial, dispneia,sopro sistólico novo, estável hemodinamicamente. Diagnóstico à cineangiocoronariografia e ao ecocardiograma de pseudoaneurisma de parede anterior de ventrículo esquerdo e CIV apical. Realizada correção cirúrgica, com ressecção do aneurisma e correção da CIV, obtendo-se ótimo resultado, apesar da gravidade do caso.

We report a rare case of double mechanical complication after anterior myocardial infarction:pseudoaneurysm and ventricular septal defect (VSD). Female patient, 66 years old, presented with typical chest pain and under went coronary angiography,which showed total occlusion in the middle third ofleft anterior descending artery (DA) with angioplasty performed 10 days after on set of symptoms. Evolved after three weeks with recurrence of chest pain, dyspnea, systolic murmur new, hemodynamically stable. Diagnostic coronary angiography and echocardiography pseudoaneurysm of the anterior wall of the left ventricle and apical VSD. Performed surgical repair with resection of the aneurysm and VSD correction, obtaining excellent results despite the gravity of the case.

Green approach—multicomponent production of boron—containing hantzsch and biginelli esters.

Multicomponent reactions are excellent methods that meet the requirements of green chemistry, by reducing the number of steps, and consequently reducing purification requirements. Accordingly, in this work, 11 novel hybrid-boron-containing molecules, namely eight 1,4-dihydropyridines and three 3,4-dihydropyrimidinones, derived from formylphenylboronic acids (ortho, meta and para), were obtained using a green approach, involving H-4CR and B-3CR practices, in the presence of ethanol, which is a green solvent, and using three comparatively different modes of activation (mantle heating, yield 3%-7% in 24 h, Infrared Radiation (IR) irradiation, yield 12%-17% in 12 h, and microwave irradiation, yield 18%-80%, requiring very low reaction times of 0.25-0.33 h). In addition, as a green-approach is offered, a convenient analysis, of the 12 green chemistry principles for the overall procedure was performed. Finally, since all the products are new, characterizations were carried out using common analytic procedures (1H, 11B, and 13C NMR, FAB+MS, HRMS, and IR). The accurate mass data of unexpected ions related to interactions between thioglycerol and the expected products, in the FAB+-mode, enabled unequivocal characterization of the target molecules.

Highly regio- and stereoselective Diels-Alder cycloadditions via two-step and multicomponent reactions promoted by infrared irradiation under solvent-free conditions.

Infrared irradiation promoted the Diels-Alder cycloadditions of exo-2-oxazolidinone dienes 1-3 with the Knoevenagel adducts 4-6, as dienophiles, leading to the synthesis of new 3,5-diphenyltetrahydrobenzo[d]oxazol-2-one derivatives (7, 9, 11 and 13-17), under solvent-free conditions. These cycloadditions were performed with good regio- and stereoselectivity, favoring the para-endo cycloadducts. We also evaluated the one-pot three-component reaction of active methylene compounds 20, benzaldehydes 21 and exo-2-oxazolidinone diene 2 under the same reaction conditions. A cascade Knoevenagel condensation/Diels-Alder cycloaddition reaction was observed, resulting in the final adducts 13-16 in similar yields. These procedures are environmentally benign, because no solvent and no catalyst were employed in these processes. The regioselectivity of these reactions was rationalized by Frontier Molecular Orbital (FMO) calculations.

Small molecule structure correctors abolish detrimental effects of apolipoprotein E4 in cultured neurons.

Apolipoprotein E4 (apoE4), the major genetic risk factor for late onset Alzheimer disease, assumes a pathological conformation, intramolecular domain interaction. ApoE4 domain interaction mediates the detrimental effects of apoE4, including decreased mitochondrial cytochrome c oxidase subunit 1 levels, reduced mitochondrial motility, and reduced neurite outgrowth in vitro. Mutant apoE4 (apoE4-R61T) lacks domain interaction, behaves like apoE3, and does not cause detrimental effects. To identify small molecules that inhibit domain interaction (i.e. structure correctors) and reverse the apoE4 detrimental effects, we established a high throughput cell-based FRET primary assay that determines apoE4 domain interaction and secondary cell- and function-based assays. Screening a ChemBridge library with the FRET assay identified CB9032258 (a phthalazinone derivative), which inhibits domain interaction in neuronal cells. In secondary functional assays, CB9032258 restored mitochondrial cytochrome c oxidase subunit 1 levels and rescued impairments of mitochondrial motility and neurite outgrowth in apoE4-expressing neuronal cells. These benefits were apoE4-specific and dose-dependent. Modifying CB9032258 yielded well defined structure-activity relationships and more active compounds with enhanced potencies in the FRET assay (IC(50) of 23 and 116 nm, respectively). These compounds efficiently restored functional activities of apoE4-expressing cells in secondary assays. An EPR binding assay showed that the apoE4 structure correction resulted from direct interaction of a phthalazinone. With these data, a six-feature pharmacophore model was constructed for future drug design. Our results serve as a proof of concept that pharmacological intervention with apoE4 structure correctors negates apoE4 detrimental effects in neuronal cells and could be further developed as an Alzheimer disease therapeutic.

Infrared assisted production of 3,4-dihydro-2(1H)-pyridones in solvent-free conditions.

A green approach for the synthesis of a set of ten 4-aryl substituted-5-alcoxy carbonyl-6-methyl-3,4-dihydro-2(1H)-pyridones using Meldrum's acid has been devised, the absence of solvent and the activation with infrared irradiation in addition to a multicomponent protocol are the main reaction conditions. The transformations proceeded with moderated yields (50-75%) with a reasonable reaction rate (3 h). It is worth noting that two novel molecules of the new class of the bis-3,4-dihydropyridones were also obtained. In addition, a comparison without the use of infrared irradiation was performed.

Effects of bentonite on p-methoxybenzyl acetate: a theoretical model for oligomerization via an electrophilic-substitution mechanism.

Tonsil Actisil FF, a commercial bentonitic clay, promotes the formation of a series of electrophilic-aromatic-substitution products from para-methoxybenzyl acetate in carbon disulfide. The molecules obtained correspond to linear isomeric dimers, trimers, tetramers and a pentamer, according to their spectroscopic data. A clear indication of the title mechanistic pathway for the oligomerization growth was obtained from the analysis of a set of computational-chemistry calculations using the density-functional-theory level B3LYP/6-311++G(d,p). The corresponding conclusions were based on the computed dipole moments, the HOMO/LUMO distributions, and a natural-populations analysis of the studied molecules.

Apolipoprotein E4 domain interaction mediates detrimental effects on mitochondria and is a potential therapeutic target for Alzheimer disease.

Apolipoprotein (apo) E4 is the major genetic risk factor for late-onset Alzheimer disease (AD). ApoE4 assumes a pathological conformation through an intramolecular interaction mediated by Arg-61 in the amino-terminal domain and Glu-255 in the carboxyl-terminal domain, referred to as apoE4 domain interaction. Because AD is associated with mitochondrial dysfunction, we examined the effect of apoE4 domain interaction on mitochondrial respiratory function. Steady-state amounts of mitochondrial respiratory complexes were examined in neurons cultured from brain cortices of neuron-specific enolase promoter-driven apoE3 (NSE-apoE3) or apoE4 (NSE-apoE4) transgenic mice. All subunits of mitochondrial respiratory complexes assessed were significantly lower in NSE-apoE4 neurons compared with NSE-apoE3 neurons. However, no significant differences in levels of mitochondrial complexes were detected between astrocytes expressing different apoE isoforms driven by the glial fibrillary acidic protein promoter, leading to our conclusion that the effect of apoE4 is neuron specific. In neuroblastoma Neuro-2A (N2A) cells, apoE4 expression reduced the levels of mitochondrial respiratory complexes I, IV, and V. Complex IV enzymatic activity was also decreased, lowering mitochondrial respiratory capacity. Mutant apoE4 (apoE4-Thr-61) lacking domain interaction did not induce mitochondrial dysfunction in N2A cells, indicating that the effect is specific to apoE4-expressing cells and dependent on domain interaction. Consistent with this finding, treatment of apoE4-expressing N2A cells with a small molecule that disrupts apoE4 domain interaction restored mitochondrial respiratory complex IV levels. These results suggest that pharmacological intervention with small molecules that disrupt apoE4 domain interaction is a potential therapeutic approach for apoE4-carrying AD subjects.

Eco-contribution for the production of N-arylnitrones: solvent-free and assisted by microwaves.

A simple green approach for the production of benzylideneaniline oxides is offered. This contribution was performed via the condensation of phenylhydroxylamine with several aryl aldehydes, in the absence of both catalyst and solvent, and using microwave irradiation as the activating reaction mode. In addition, good yields of the products were achieved in a short time. It is also worth noting that the work-up procedure is simple and the products do not require further purification. Finally, an interesting comparison without the use of microwave irradiation is also discussed.