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Se estudió el complejo de cambio en suelos aluviales recientes, terrazas medias y terrazas altas del Municipio de Marinilla por el método rápido de Brown. El grado de saturación, bajo en todos ellos, se acentúa en los suelos de las terrazas más antiguas y nos indica el bajo nivel de fertilidad de estos suelos. La extracción del hidrógeno de cambio con acetato cálcico coincide con la que efectúa el acetato amónico, excepto para los suelos más ricos en materia orgánica con los que proporciona resultados más altos la solución extractora de acetato cálcico.

The Sudano-Sahelian zone of West Africa, one of the poorest of the Earth, is characterized by high rainfall variability and rapid population growth. In this region, heavy storm events frequently cause extensive damage. Nonetheless, the projections for change in extreme rainfall values have shown a great divergence between Regional Climate Models (RCM), increasing the forecast uncertainty. Novel methodologies should be applied, taking into account both the variability provided by different RCMs, as well as the non-stationary nature of time series for the building of hazard maps of extreme rainfall events. The present work focuses on the probability density functions (PDFs)-based evaluation and a simple quantitative measure of how well each RCM considered can capture the observed annual maximum daily rainfall (AMDR) series on the Senegal River basin. Since meaningful trends have been detected in historical rainfall time series for the region, non-stationary probabilistic models were used to fit the PDF parameters to the AMDR time series. In the development of PDF ensemble by bootstrapping techniques, Reliability Ensemble Averaging (REA) maps were applied to score the RCMs. The REA factors were computed using a metric to evaluate the agreement between observed -or best estimated- PDFs, and that simulated with each RCM. The assessment of plausible regional trends associated to the return period, from the hazard maps of AMDR, showed a general rise, owing to an increase in the mean and the variability of extreme precipitation. These spatialtemporal distributions could be considered by Organization for the Development of the Senegal River (Organisation pour la mise en valeur du fleuve Sénégal, OMVS), in such a way as to reach a better balance between mitigation and adaptation. [ABSTRACT FROM AUTHOR]

The Sudano-Sahelian zone ofWest Africa, one of the poorest of the Earth, is characterized by high rainfall variability and rapid population growth. In this region, heavy storm events frequently cause extensive damage. Nonetheless, the projections for change in extreme rainfall values have shown a great divergence between Regional Climate Models (RCM), increasing the forecast uncertainty. Novel methodologies should be applied, taking into account both the variability provided by different RCMs, as well as the non-stationary nature of time series for the building of hazard maps of extreme rainfall events. The present work focuses in the probability density functions (PDFs)-based evaluation and a simple quantitative measure of how well each RCM considered can capture the observed annual maximum daily rainfall (AMDR) series on the Senegal River basin. Since meaningful trends have been detected in historical rainfall time series for the region, non-stationary probabilistic models were used to fit the PDF parameters to the AMDR time series. In the development of PDF ensemble by bootstrapping techniques, Reliability Ensemble Averaging (REA) maps were applied to score the RCMs. The REA factors were computed using a metric to evaluate the agreement between observed -or best estimated- PDFs, and that simulated with each RCM. The assessment of plausible regional trends associated to the return period, from the hazard maps of AMDR, showed a general rise, owing to an increase in the mean and the variability of extreme precipitation. These spatial-temporal distributions could be considered by local stakeholders in such a way as to reach a better balance between mitigation and adaptation. [ABSTRACT FROM AUTHOR]

We present some non-standard, finite-difference schemes to approximate positive solutions of a modified Fisher-KPP equation that appears in the study of population dynamics. The methods are consistent order [image omitted] , and they provide non-negative approximations for any choice of non-negative initial profile. Associated with each technique, we present an energy scheme that consistently approximates the energy of the system. The methods are validated against known analytical solutions for an initial-boundary-value problem and an initial-value problem, and a Neumann stability analysis is carried out in detail; moreover, a comparison with respect to a standard, higher-order method reveals that our methods are more stable and more accurate when positivity restrictions are to be observed. The stability of our methods - even in the presence of discontinuities - is numerically revealed after examining the propagation of Heaviside fronts. [ABSTRACT FROM AUTHOR]

The applications of mullite based ceramics cause that along their useful life they are subjected to important mechanical and thermal solicitations. This is the reason why it is very interesting to establish procedures that allow to predict their behaviour in function of the initial condition. For this work the ceramic used was a 2Al2O3:1SiO2 mullite material obtained using a method of chemical processing of kaolinite and aluminium metal wastes. Mullite based ceramic materials with different sintering grade were obtained using various firing conditions. Strength of ceramics was measured in four point bending test. Weibull distribution function was used to characterize statistically the variation of the mechanical strength. A surface flaws mapping was established by scanning electron microscopy and distributions of pore-size, orientation and shape factor were obtained for each sample. A study of strength is done using Weibull´s theory and the surface flaws mapping.Las aplicaciones propias de los materiales cerámicos de mullita propician que a lo largo de su vida útil se vean sometidos a importantes solicitaciones mecánicas y térmicas. Es por ello interesante establecer procedimientos que permitan predecir su comportamiento en función del estado inicial. Para este estudio se utilizó una mullita del tipo 2Al2O3:1SiO2 obtenida usando un método de procesado químico a partir de caolinita y residuos de aluminio. Se fabricaron varias series de dicho material para ser sometidas a distintos ciclos de cocción que proporcionasen materiales con diferente grado de sinterización. La resistencia a la fractura de dichas cerámicas se determinó mediante ensayo a flexión en cuatro puntos. La función de distribución de Weibull se usó para caracterizar estadísticamente la variación de la resistencia mecánica. A continuación se procedió al estudio de su superficie por microscopía electrónica de barrido, para establecer un mapeado de defectos que posibilitase la obtención de la distribución de tamaño de poro, orientación y factor de forma de cada probeta. Finalmente se llevó a cabo un estudio de resistencia usando la teoría de Weibull y el mapeado de defectos superficiales.

We aimed to assess patient exposure to isavuconazole (ISZ) from samples received in our laboratory for therapeutic antifungal monitoring. We used liquid chromatography coupled with ultraviolet (UV) absorbance detection adapted from a multiplex-validated method with photodiode array (PDA) detection to monitor the analytes. The latter device allows the characterization of the azoles UV spectra. The method was validated according to international guidelines for efficient ISZ monitoring. The assay exhibited linearity between 0.25 and 16 mg/l for ISZ. Accuracy and intra- and inter-day precision were within acceptable ranges, and the method was successfully applied to quantify azoles and major metabolites from clinical samples collected from treated patients. We focus on ISZ blood concentrations and compared them to those of voriconazole, posaconazole, and itraconazole for a period of 5 years (2017-2021). Median ISZ concentration was 2.92 mg/l (interquartile range 1.82-5.33 mg/l) with 89% of measurements classified as adequate exposure (> 1 mg/l). Additionally, 71% of samples reach concentration values > 2 mg/l. Different ISZ exposure between adults to children were found. In conclusion, ISZ achieves excellent blood concentrations compared to other azole drugs, they are almost identical to those previously described, they exceed the MICs of most fungi for which its use was recommended and they differ depending on the patient's age. The method we describe for antifungal monitoring is simple, robust, and efficient. It simultaneously analyzes azoles and metabolites, and can be used for tailored interventions, achieve exposures associated with therapeutic success, decrease treatment-related toxicity, and help prevent resistance emergence due to continuous azole sub-optimal concentrations., (© The Author(s) 2023. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology.)

The tool created aims at the environmental monitoring of the Mar Menor coastal lagoon (Spain) and the monitoring of the land use of its watershed. It integrates heterogeneous data sources ranging from ecological data obtained from a multiparametric oceanographic sonde to agro-meteorological data from IMIDA's network of stations or hydrological data from the SAIH network as multispectral satellite images from Sentinel and Landsat space missions. The system is based on free and open source software and has been designed to guarantee maximum levels of flexibility and scalability and minimum coupling so that the incorporation of new components does not affect the existing ones. The platform is designed to handle a data volume of more than 12 million records, experiencing exponential growth in the last six months. The tool allows the transformation of a large volume of data into information, offering them through microservices with optimal response times. As practical applications, the platform created allows us to know the ecological state of the Mar Menor with a very high level of detail, both at biophysical and nutrient levels, being able to detect periods of oxygen deficit and delimit the affected area. In addition, it facilitates the detailed monitoring of the cultivated areas of the watershed, detecting the agricultural use and crop cycles at the plot level. It also makes it possible to calculate the amount of water precipitated on the watershed and to monitor the runoff produced and the amount of water entering the Mar Menor in extreme events. The information is offered in different ways depending on the user profile, offering a very high level of detail for research or data analysis profiles, concrete and direct information to support decision-making for users with managerial profiles and validated and concise information for citizens. It is an integrated and distributed system that will provide data and services for the Mar Menor Observatory.

Malaria, babesiosis, trypanosomosis, and leishmaniasis are some of the most life-threatening parasites, but the range of drugs to treat them is limited. An effective, safe, and low-cost drug with a large activity spectrum is urgently needed. For this purpose, an aryl amino alcohol derivative called Alsinol was resynthesized, screened in silico, and tested against Plasmodium, Babesia, Trypanosoma, and Leishmania. In silico Alsinol follows the Lipinski and Ghose rules. In vitro it had schizontocidal activity against Plasmodium falciparum and was able to inhibit gametocytogenesis; it was particularly active against late gametocytes. In malaria-infected mice, it showed a dose-dependent activity similar to chloroquine. It demonstrated a similar level of activity to reference compounds against Babesia divergens, and against promastigotes, and amastigotes stages of Leishmania in vitro. It inhibited the in vitro growth of two African animal strains of Trypanosoma but was ineffective in vivo in our experimental conditions. It showed moderate toxicity in J774A1 and Vero cell models. The study demonstrated that Alsinol has a large spectrum of activity and is potentially affordable to produce. Nevertheless, challenges remain in the process of scaling up synthesis, creating a suitable clinical formulation, and determining the safety margin in preclinical models.

Background: The challenge in anti-malarial chemotherapy is based on the emergence of resistance to drugs and the search for medicines against all stages of the life cycle of Plasmodium spp. as a therapeutic target. Nowadays, many molecules with anti-malarial activity are reported. However, few studies about the cellular and molecular mechanisms to understand their mode of action have been explored. Recently, new primaquine-based hybrids as new molecules with potential multi-acting anti-malarial activity were reported and two hybrids of primaquine linked to quinoxaline 1,4-di-N-oxide (PQ-QdNO) were identified as the most active against erythrocytic, exoerythrocytic and sporogonic stages., Methods: To further understand the anti-malarial mode of action (MA) of these hybrids, hepg2-CD81 were infected with Plasmodium yoelii 17XNL and treated with PQ-QdNO hybrids during 48 h. After were evaluated the production of ROS, the mitochondrial depolarization, the total glutathione content, the DNA damage and proteins related to oxidative stress and death cell., Results: In a preliminary analysis as tissue schizonticidals, these hybrids showed a mode of action dependent on peroxides production, but independent of the activation of transcription factor p53, mitochondrial depolarization and arrest cell cycle., Conclusions: Primaquine-quinoxaline 1,4-di-N-oxide hybrids exert their antiplasmodial activity in the exoerythrocytic phase by generating high levels of oxidative stress which promotes the increase of total glutathione levels, through oxidation stress sensor protein DJ-1. In addition, the role of HIF1a in the mode of action of quinoxaline 1,4-di-N-oxide is independent of biological activity.

Emergence of drug resistance and targeting all stages of the parasite life cycle are currently the major challenges in antimalarial chemotherapy. Molecular hybridization combining two scaffolds in a single molecule is an innovative strategy for achieving these goals. In this work, a series of novel quinoxaline 1,4-di-N-oxide hybrids containing either chloroquine or primaquine pharmacophores was designed, synthesized and tested against both chloroquine sensitive and multidrug resistant strains of Plasmodium falciparum. Only chloroquine-based compounds exhibited potent blood stage activity with compounds 4b and 4e being the most active and selective hybrids at this parasite stage. Based on their intraerythrocytic activity and selectivity or their chemical nature, seven hybrids were then evaluated against the liver stage of Plasmodium yoelii, Plasmodium berghei and Plasmodium falciparum infections. Compound 4b was the only chloroquine-quinoxaline 1,4-di-N-oxide hybrid with a moderate liver activity, whereas compound 6a and 6b were identified as the most active primaquine-based hybrids against exoerythrocytic stages, displaying enhanced liver activity against P. yoelii and P. berghei, respectively, and better SI values than primaquine. Although both primaquine-quinoxaline 1,4-di-N-oxide hybrids slightly reduced the infection of mosquitoes, they inhibited sporogony of P. berghei and compound 6a showed 92% blocking of transmission. In vivo liver efficacy assays revealed that compound 6a showed causal prophylactic activity affording parasitaemia reduction of up to 95% on day 4. Absence of genotoxicity and in vivo acute toxicity were also determined. These results suggest the approach of primaquine-quinoxaline 1,4-di-N-oxide hybrids as new potential dual-acting antimalarials for further investigation., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

Design, synthesis, structure-activity relationship, cytotoxicity studies, in silico drug-likeness, genotoxicity screening, and in vivo studies of new 1-aryl-3-substituted propanol derivatives led to the identification of nine compounds with promising in vitro (55, 56, 61, 64, 66, and 70-73) and in vivo (66 and 72) antimalarial profiles against Plasmodium falciparum and Plasmodium berghei. Compounds 55, 56, 61, 64, 66 and 70-73 exhibited potent antiplasmodial activity against chloroquine-resistant strain FCR-3 (IC 50 s < 0.28 μM), and compounds 55, 56, 64, 70, 71, and 72 showed potent biological activity in chloroquine-sensitive and multidrug-resistant strains (IC 50 s < 0.7 μM for 3D7, D6, FCR-3 and C235). All of these compounds share appropriate drug-likeness profiles and adequate selectivity indexes (77 < SI < 184) as well as lack genotoxicity. In vivo efficacy tests in a mouse model showed compounds 66 and 72 to be promising candidates as they exhibited significant parasitemia reductions of 96.4% and 80.4%, respectively. Additional studies such as liver stage and sporogony inhibition, target exploration of heat shock protein 90 of P. falciparum, targeted delivery by immunoliposomes, and enantiomer characterization were performed and strongly reinforce the hypothesis of 1-aryl-3-substituted propanol derivatives as promising antimalarial compounds., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

Most drugs currently entering the clinical pipeline for severe malaria therapeutics are of lipophilic nature, with a relatively poor solubility in plasma and large biodistribution volumes. Low amounts of these compounds do consequently accumulate in circulating Plasmodium-infected red blood cells, exhibiting limited antiparasitic activity. These drawbacks can in principle be satisfactorily dealt with by stably encapsulating drugs in targeted nanocarriers. Here this approach has been adapted for its use in immunocompetent mice infected by the Plasmodium yoelii 17XL lethal strain, selected as a model for human blood infections by Plasmodium falciparum. Using immunoliposomes targeted against a surface protein characteristic of the murine erythroid lineage, the protocol has been applied to two novel antimalarial lipophilic drug candidates, an aminoquinoline and an aminoalcohol. Large encapsulation yields of >90% were obtained using a citrate-buffered pH gradient method and the resulting immunoliposomes reached in vivo erythrocyte targeting and retention efficacies of >80%. In P. yoelii-infected mice, the immunoliposomized aminoquinoline succeeded in decreasing blood parasitemia from severe to uncomplicated malaria parasite densities (i.e. from ≥25% to ca. 5%), whereas the same amount of drug encapsulated in non-targeted liposomes had no significant effect on parasite growth. Pharmacokinetic analysis indicated that this good performance was obtained with a rapid clearance of immunoliposomes from the circulation (blood half-life of ca. 2 h), suggesting a potential for improvement of the proposed model., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

It has been over a century since Carlos Chagas discovered the Trypanosoma cruzi (T. cruzi) as the causative agent of Chagas disease (CD), a neglected tropical disease with several socioeconomic, epidemiological and human health repercussions. Currently, there are only two commercialized drugs to treat CD in acute phase, nifurtimox and benznidazol, with several adverse side effects. Thus, new orally available and safe drugs for this parasitic infection are urgently required. One strategy of great importance in new drug discovery programmes is based on the search of molecules enabling to interfere with enzymes involved in T. cruzi metabolism. This review will focus on two of the most promising targets for the therapy of CD: trypanothione reductase (TR) and the iron-containing superoxide dismutase (Fe- SOD), which protect the parasite against oxidative damage by reactive oxygen species. A brief comparison of the function, mechanism of action and the active sites between T. cruzi TR and Fe-SOD with their analogues enzymes in human, glutathione reductase (GR) and the corresponding SODs, will be discussed. This review will also summarize the recent development and structure-activity relationships of novel compounds reported for their ability to selectively inhibit these targets, aiming to define molecular bases in the search for new effective treatment of CD., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

We report the design (in silico ADMET criteria), synthesis, cytotoxicity studies (HepG-2 cells), and biological evaluation of 15 hydrazine/hydrazide quinoxaline 1,4-di-N-oxide derivatives against the 3D7 chloroquine sensitive strain and FCR-3 multidrug resistant strain of Plasmodium falciparum and Leishmania infantum (axenic amastigotes). Fourteen of derivatives are novel quinoxaline 1,4-di-N-oxide derivatives. Compounds 18 (3D7 IC 50 =1.40μM, FCR-3 IC 50 =2.56μM) and 19 (3D7 IC 50 =0.24μM, FCR-3 IC 50 =2.8μM) were identified as the most active against P. falciparum, and they were the least cytotoxic (CC 50 -values>241μM) and most selective (SI>86). None of the compounds tested against L. infantum were considered to be active. Additionally, the functional role of the hydrazine and hydrazide structures were studied in the quinoxaline 1,4-di-N-oxide system., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Synthesis of new 1-aryl-3-substituted propanol derivatives followed by structure-activity relationship, in silico drug-likeness, cytotoxicity, genotoxicity, in silico metabolism, in silico pharmacophore modeling, and in vivo studies led to the identification of compounds 22 and 23 with significant in vitro antiplasmodial activity against drug sensitive (D6 IC 50  ≤ 0.19 μM) and multidrug resistant (FCR-3 IC 50  ≤ 0.40 μM and C235 IC 50  ≤ 0.28 μM) strains of Plasmodium falciparum. Adequate selectivity index and absence of genotoxicity was also observed. Notably, compound 22 displays excellent parasitemia reduction (98 ± 1%), and complete cure with all treated mice surviving through the entire period with no signs of toxicity. One important factor is the agreement between in vitro potency and in vivo studies. Target exploration was performed; this chemotype series exhibits an alternative antimalarial mechanism., (Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.)

We report the synthesis and antimalarial activities of eighteen quinoxaline and quinoxaline 1,4-di-N-oxide derivatives, eight of which are completely novel. Compounds 1a and 2a were the most active against Plasmodium falciparum strains. Structure-activity relationships demonstrated the importance of an enone moiety linked to the quinoxaline ring.

As a continuation of our research and with the aim of obtaining new agents against Chagas disease, an extremely neglected disease which threatens 100 million people, eighteen new quinoxaline 1,4-di-N-oxide derivatives have been synthesized following the Beirut reaction. The synthesis of the new derivatives was optimized through the use of a new and more efficient microwave-assisted organic synthetic method. The new derivatives showed excellent in vitro biological activity against Trypanosoma cruzi. Compound 17, which was substituted with fluoro groups at the 6- and 7-positions of the quinoxaline ring, was the most active and selective in the cytotoxicity assay. The electrochemical study showed that the most active compounds, which were substituted by electron-withdrawing groups, possessed a greater ease of reduction of the N-oxide groups., (Copyright © 2013 Elsevier Masson SAS. All rights reserved.)

Malaria and leishmaniasis are two of the World's most important tropical parasitic diseases. Continuing with our efforts to identify new compounds active against malaria and leishmaniasis, twelve new 1,4-di-N-oxide quinoxaline derivatives were synthesized and evaluated for their in vitro antimalarial and antileishmanial activity against Plasmodium falciparum FCR-3 strain, Leishmania infantum and Leishmania amazonensis. Their toxicity against VERO cells (normal monkey kidney cells) was also assessed. The results obtained indicate that a cyclopentyl derivative had the best antiplasmodial activity (2.9 µM), while a cyclohexyl derivative (2.5 µM) showed the best activity against L. amazonensis, and a 3-chloropropyl derivative (0.7 µM) showed the best results against L. infantum. All these compounds also have a Cl substituent in the R⁷ position.

Malaria and leishmaniasis are two of the World's most important tropical parasitic diseases. Thirteen new 2-cyano-3-(4-phenylpiperazine-1-carboxamido) quinoxaline 1,4-dioxide derivatives (CPCQs) were synthesized and evaluated for their in vitro antimalarial and antileishmanial activity against erythrocytic forms of Plasmodium falciparum and axenic forms of Leishmania infantum. Their toxicity against VERO cells (normal monkey kidney cells) was also assessed. None of the tested compounds was efficient against Plasmodium, but two of them showed good activity against Leishmania. Toxicity on VERO was correlated with leishmanicidal properties.

Ever since the idea arose that melatonin might promote sleep and resynchronize circadian rhythms, many research groups have centered their efforts on obtaining new melatonin receptor ligands whose pharmacophores include an aliphatic chain of variable length united to an N-alkylamide and a methoxy group (or a bioisostere), linked to a central ring. Substitution of the indole ring found in melatonin with a naphthalene or quinoline ring leads to compounds of similar affinity. The next step in this structural approximation is to introduce a quinoxaline ring (a bioisostere of the quinoline and naphthalene rings) as the central nucleus of future melatoninergic ligands.

The combination of antagonism at histamine H(3) receptor and the stimulation of insulin secretion have been proposed as an approach to new dual therapeutic agents for the treatment of type 2 diabetes mellitus associated with obesity. We have designed and synthesized a new series of non-imidazole derivatives, based on a basic amine ring connected through an alkyl spacer of variable length to a phenoxysulfonylurea moiety. These compounds were initially evaluated for histamine H(3) receptor binding affinities, suggesting that a propoxy chain linker between the amine and the core ring could be essential for optimal binding affinity. Compound 56, 1-(naphthalen-1-yl)-3-[(p-(3-pyrrolidin-1-ylpropoxy)benzene)]sulfonylurea exhibited the best H(3) antagonism affinity. However, since all these derivatives failed to block K(ATP) channels, the link of these two related moieties should not be considered a good pharmacophore for obtaining new dual H(3) antagonists with insulinotropic activity, suggesting the necessity to propose a new chemical hybrid prototype., (Copyright © 2012 Elsevier Masson SAS. All rights reserved.)

In 2003, the Pan American Health Organization (PAHO) adopted a resolution calling for rubella and congenital rubella syndrome (CRS) elimination in the Americas by the year 2010. To accomplish this goal, PAHO advanced a rubella and CRS elimination strategy including introduction of rubella-containing vaccines into routine vaccination programs accompanied by high immunization coverage, interruption of rubella transmission through mass vaccination of adolescents and adults, and strengthened surveillance for rubella and CRS. The rubella elimination strategies were aligned with the successful measles elimination strategies. By the end of 2009, all countries routinely vaccinated children against rubella, an estimated 450 million people had been vaccinated against measles and rubella in supplementary immunization activities, and rubella transmission had been interrupted. This article describes how the region eliminated rubella and CRS.

In the region of the Americas, goals for the elimination of endemic measles and rubella/congenital rubella syndrome (CRS) by the year 2000 and 2010, respectively were established. The successful implementation of measles elimination strategies in the region of the Americas resulted in the interruption of endemic measles transmission in 2002 and tremendous progress toward rubella and CRS elimination. In October 2007, the 27th Pan American Sanitary Conference adopted Resolution CSP27.R2 urging member states to begin documenting and verifying the interruption of endemic transmission of the measles and rubella viruses in the Americas. To ensure a standardized approach for the process of documentation and verification, the Pan American Health Organization/World Health Organization (PAHO/WHO) developed a regional plan of action to guide countries and their national commissions as they prepare and consolidate evidence of the interruption of endemic measles and rubella transmission. This article summarizes the plan of action including the essential criteria and components of the guidelines.

Continuing with our efforts to identify new active compounds against malaria and leishmaniasis, 14 new 3-amino-1,4-di-N-oxide quinoxaline-2-carbonitrile derivatives were synthesized and evaluated for their in vitro antimalarial and antileishmanial activity against Plasmodium falciparum Colombian FCR-3 strain and Leishmania amazonensis strain MHOM/BR/76/LTB-012A. Further computational studies were carried out in order to analyze graphic SAR and ADME properties. The results obtained indicate that compounds with one halogenous group substituted in position 6 and 7 provide an efficient approach for further development of antimalarial and antileishmanial agents. In addition, interesting ADME properties were found., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

The increase in the prevalence of drug-resistant tuberculosis cases demonstrates the need of discovering new and promising compounds with antimycobacterial activity. As a continuation of our research and with the aim of identifying new antitubercular drugs candidates, a new series of quinoxaline 1,4-di-N-oxide derivatives containing isoniazid was synthesized and evaluated for in vitro anti-tuberculosis activity against Mycobacterium tuberculosis H37Rv strain. Moreover, various drug-like properties of new compounds were predicted. Taking into account the biological results and the promising drug-likeness profile of these compounds, make them valid leads for further experimental research., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Piperazine and pyrrolidine derivatives were synthesised and evaluated for their capacity to inhibit the growth of Plasmodium falciparum chloroquine-resistant (FCR-3) strain in culture. The combined presence of a hydroxyl group, a propane chain and a fluor were shown to be crucial for the antiplasmodial activity. Five compounds of the aryl-alcohol series inhibited 50% of parasite growth at doses ≤10 μM. The most active compound 1-(4-fluoronaphthyl)-3-[4-(4-nitro-2-trifluoromethylphenyl)piperazin-1-yl] propan-1-ol was almost 20-40 times more active on P. falciparum (IC(50): 0.5 μM) than on tumorogenic and non-tumorogenic cells. In vivo it has a very weak effect; inhibiting 35% of parasite growth only, at 10 mg/kg/day against Plasmodium berghei infected mice without any impact on survival time. In silico molecular docking study and molecular electrostatic potential calculation revealed that this compound bound to the active site of Plasmodium plasmepsin II enzyme., (Copyright © 2011 Elsevier Inc. All rights reserved.)

We report benzo[b]thiophene derivatives synthesized according to a dual strategy. 8j, 9c, and 9e with affinity values toward 5-HT(7)R and 5-HTT were selected to probe their antidepressant activity in vivo using the forced swimming text (FST). The results showed significant antidepressant activity after chronic treatment. 9c was effective in reducing the immobility time in FST even after acute treatment. These findings identify these compounds as a new class of antidepressants with a rapid onset of action.

Melanin-concentrating hormone (MCH) regulates feeding and energy homeostasis through interaction with its receptor, the melanin-concentrating receptor 1 (MCHR1), making it a target in the treatment of obesity. Molecular modeling and docking studies were performed in order to find a binding model for the docking of two new series of MCHR1 antagonists to the receptor. Results suggested interactions between the ligands and two glutamines (Gln5.42 and Gln6.55) not conserved in many of the GPCRs family members. Histamine 3 receptor (HRH3) presents two apolar residues in the aforementioned positions and the available biological data against this receptor supported the role of the two glutamines in the binding of antagonists to the MCHR1. This knowledge could be useful in the development of new, more active and more selective MCHR1 antagonists., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

This paper describes the synthesis and in vitro antimalarial activity against a P. falciparum 3D7 strain of some new 1-aryl-3-substituted propanol derivatives. Twelve of the tested compounds showed an IC(50) lower than 1 microM. These compounds were also tested for cytotoxicity in murine J774 macrophages. The most active compounds were evaluated for in vivo activity against P. berghei in a 4-day suppressive test. Compound 12 inhibited more than 50% of parasite growth at a dose of 50 mg/kg/day. In addition, an FBIT test was performed to measure the ability to inhibit ferriprotoporphyrin biocrystallization. This data indicates that 1-aryl-3-substituted propanol derivatives hold promise as a new therapeutic option for the treatment of malaria.

Obesity is a chronic disease characterized by the accumulation of excess adipose tissue associated with an increased risk of multiple morbidities and mortality. At the present time, only three drugs have been approved by the Food and Drug Administration (FDA) for the treatment of obesity. Agonists and antagonists of some of the substances implicated in the regulation of energy homeostasis represent opportunities for anti-obesity drug development. The most promising targets are alpha-melanocyte stimulating hormone (alpha-MSH) receptors, cannabinoid receptors, the 5-hydroxytryptamine (5-HT) receptors and melanin-concentrating hormone (MCH) receptors. MCH receptors could be major potential targets for the treatment of obesity. Many pharmaceutical companies have described MCH-R1 antagonists that have appeared over the past year. Recently, two compounds went into phase I clinical trials that evaluate MCH receptor antagonists as a new perspective for the pharmacologic treatment of obesity. In this review, structure-activity relationships (SAR) in the development of MCH-R1 antagonists are provided.