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Resumen Introducción. A nivel mundial los tumores gastrointestinales tienen un impacto importante en la mortalidad y se asocian a diferentes factores, entre ellos regionales y sociodemográficos. El objetivo de este estudio fue describir la variación en el tiempo del cáncer gastrointestinal en una población del centro occidente de Colombia, dada su alta incidencia y desenlace frecuentemente fatal. Métodos. Se realizó un estudio retrospectivo observacional con muestreo no probabilístico en un tiempo de seis años. Se seleccionaron pacientes diagnosticados con algún tipo de neoplasia del tracto digestivo, en un hospital de tercer nivel del centro occidente de Colombia. Resultados. Se evaluaron un total de 1152 pacientes. Los tumores del tracto digestivo superior (esófago, unión esófago-gástrica y estómago) fueron los más frecuentes (44 %), seguidos de los tumores del tracto digestivo medio e inferior (intestino delgado, colon, recto y ano; 31 %) y de los tumores hepato-bilio-pancreáticos (25 %). La edad media de presentación fue 64,6 años, con una mayor frecuencia en el sexo masculino (51,6 %). El adenocarcinoma fue el tipo histológico más común. Conclusión. Los resultados de este estudio muestran que los tumores gastrointestinales son una neoplasia frecuente en nuestro país, siendo los tumores gástricos los que se presentan con mayor prevalencia, seguidos de los tumores colorrectales y las neoplasias biliopancreáticas, las cuales se mantiene en el tiempo. Abstract Introduction. Worldwide, gastrointestinal tumors have a significant impact on mortality and are associated with different factors, including regional and sociodemographics. The objective of this study was to describe the variation over time of gastrointestinal cancer in a population from Central-Western Colombia, given its high incidence and frequently fatal outcome. Methods. An observational retrospective study with non-probabilistic sampling was carried out over a period of six years. Patients diagnosed with some type of neoplasm of the digestive tract were selected in a tertiary care hospital in the Central-Western Colombia. Results. A total of 1152 patients were evaluated. Tumors of the upper digestive tract (esophagus, esophagogastric junction, and stomach) were the most frequent (44%), followed by tumors of the middle and lower digestive tract (small intestine, colon, rectum and anus; 31%), and hepatobiliary-pancreatic tumors (25%). The mean age of presentation was 64.6 years with a higher frequency in males (51.6%). Adenocarcinoma was the most common histological type. Conclusion. The results of this study show that gastrointestinal tumors are a frequent neoplasm in our country, with gastric tumors being the most prevalent, followed by colorectal tumors and biliopancreatic neoplasms, which are maintained over time.

Avocado (Persea americana Mill) is a native American fruit. Its industrial processing generates a large number of wastes (leaves, peels, and seeds). These wastes are a source of bioactive c...

Palatability is amongst the most important determinants of whether or not a child will take a medicine. In order to increase concordance with treatment regimens it is often necessary to utilise a range of formulation techniques to improve the palatability of medicines. These can include selecting a different molecule or version of a molecule (such as a different polymorph or salt form), various taste masking techniques and/or the inclusion of flavours and sweeteners. In order to be able to understand the taste of the Active Pharmaceutical Ingredient (API) and to validate the formulation approach used, it is necessary to be able to use the most reliable taste evaluation method possible. Multiple in vivo and in vitro methods exist nowadays or are proposed in the literature but are often little understood by the pharmaceutical product development community. In particular, different methods may be more relevant at different stages of product development. The aim of this article is to propose a tool to guide the selection of the most appropriate method for the desired evaluation. A spreadsheet-based tool is proposed that is designed to allow the systematic assessment of the applicability of any taste assessment technique existing or new to the users proposed application. A series of criteria are defined that will allow the user to assess the analytical, usability and availability factors for the technique that is being considered. Such a systematic review will help the user to understand the benefits and risks of using each methodology for that application. The use of the tool is illustrated based on currently available data and literature. As new/existing methods are developed/improved, the outcomes of the tool may change.

Merging biological systems with electronic components requires converting biological ionic currents into electrical signals. Previously, we coupled green-light-activated transport of protons by a palladium-binding version of

Blue-absorbing proteorhodopsin (BPR) from marine bacteria is a retinal-bound, light-activated, outwards proton transporter containing seven α-helical transmembrane segments (TMS). It is synthesized as a precursor species (pre-BPR) with a predicted N-terminal signal sequence that is cleaved to yield the mature protein. While optimizing the production of BPR in Escherichia coli to facilitate the construction of bioprotonic devices, we observed significant pre-BPR accumulation in the inner membrane and explored signal sequence requirements and export pathway. We report here that BPR does not rely on the Sec pathway for inner membrane integration, and that although it greatly enhances yields, its signal sequence is not necessary to obtain a functional product. We further show that an unprocessable version of pre-BPR obtained by mutagenesis of the signal peptidase I site exhibits all functional attributes of the wild-type protein and has the advantage of being produced at higher levels. Our results are consistent with the BPR signal sequence being recognized by the signal recognition particle (SRP; a protein that orchestrates the cotranslational biogenesis of inner membrane proteins) and serving as a beneficial "pro" domain rather than a traditional secretory peptide.

Objectives: The present study evaluates novel cationic quinoline derivatives known as benzimidazo[3,2-a]quinolinium salts (BQS) named NBQ-48 and ABQ-48 that have structural similarities to known anti-cancer substances such as ellipticine and berberine. Methods: Toledo human lymphoma (ATCC CRL2631) cells were treated for 24 to 48 hours. Apoptosis related endpoints such as cell cycle arrest, mitochondrial damage, RNS and ROS generation and the activity of several apoptosis related proteins such as caspases and apoptosis inducing factor (AIF) were studied using fluorescence staining and western blot respectively. Results: Results indicated a higher toxicity from the amino substituted ABQ-48 versus the NBQ-48 (GI50’s of 50uM versus 100uM respectively). Both compounds induced cell death through various apoptosis related endpoints including a decrease in mitochondrial membrane potential with an increase in ROS and activation of the effector caspase 3. Interestingly, AIF release was observed on cells treated with the amino substituted ABQ-48 but not on the nitro substituted NBQ-48 samples suggesting a caspase independent mechanism for ABQ-48. Conclusions: The results obtained presents the toxic effects of two novel benzimidazo[3,2-a]quinolinium salts in human lymphoma tumor cells. The identified mechanism of action includes multiple apoptosis related effects. Furthermore the data presents a clear variation in caspase dependent or independent mechanism for each compound.

Fusion of a palladium-binding peptide to an archaeal rhodopsin promotes intimate integration of the lipid-embedded membrane protein with a palladium hydride protonic contact. Devices fabricated with the palladium-binding deltarhodopsin enable light-activated conversion of protonic currents to electronic currents with on/off responses complete in seconds and a nearly tenfold increase in electrical signal relative to those made with the wild-type protein.

The rodent brief-access taste aversion (BATA) model is an efficient in vivo screening tool for taste assessment. A new E max (maximum effect attributable to the drug) model was developed and further investigated in comparison with three previously published models for analysing the rodent BATA data; the robustness of all the models was discussed. The rodent BATA data were obtained from a series of experiments conducted with a bitter reference compound, quinine hydrochloride dihydrate (QHD). A new E max model that could be applied to both “lick numbers” and “lick ratios” was built and three published models that used lick ratios were employed for analysing the BATA data. IC 50 , the concentration that inhibits 50% of the maximum lick numbers, quantified the oral aversiveness of QHD. One thousand bootstrap datasets were generated from the original data. All models were applied to estimate the confidence intervals of the IC 50s without symmetric assumption. The IC 50 value obtained from the new E max model was 0.0496 mM (95% CI 0.0297–0.0857) using the lick numbers for analysis, while an IC 50 of 0.0502 mM (95% CI 0.0267–0.0859) was acquired with the lick ratios. Except one published model, the IC 50 values have a similar range for the 95% CI. The new E max model enabled the analysis of both “lick numbers” and “lick ratios” whereas other models could only handle data presented as “lick ratios”. IC 50s obtained with these two types of datasets showed similarity among all models thereby justified the robustness of the new E max model.

Harmonized methodologies are urgently required for the taste evaluation of novel pediatric medicines. This study utilized in vitro, in vivo and clinical data to evaluate the palatability of a novel midazolam chocolate tablet. In vitro dissolution experiments showed the crushed tablet to release within 5 min 1.68 mg of midazolam into simulated saliva. This translated to a drug level of 0.84 mg/ml in the oral cavity, which would be higher than the midazolam bitterness detection threshold concentration of 0.03 mg/ml determined in a rat 'brief access taste aversion' (BATA) model. The visual analogue scale scores of patients aged 4-16 years prescribed with midazolam pre-surgery showed a clear preference for the midazolam chocolate tablets (3.35 ± 1.04, n = 20) compared to the control midazolam solution (1.47 ± 0.62, n = 17). The clinical data was in agreement with the in vivo rodent data in showing the novel chocolate tablet matrix to be effective at taste-masking the bitter midazolam.

Car9, a dodecapeptide identified by cell surface display for its ability to bind to the edge of carbonaceous materials, also binds to silica with high affinity. The interaction can be disrupted with l-lysine or l-arginine, enabling a broad range of technological applications. Previously, we reported that C-terminal Car9 extensions support efficient protein purification on underivatized silica. Here, we show that the Car9 tag is functional and TEV protease-excisable when fused to the N-termini of target proteins, and that it supports affinity purification under denaturing conditions, albeit with reduced yields. We further demonstrate that capture of Car9-tagged proteins is enhanced on small particle size silica gels with large pores, that the concomitant problem of nonspecific protein adsorption can be solved by lysing cells in the presence of 0.3% Tween 20, and that efficient elution is achieved at reduced l-lysine concentrations under alkaline conditions. An optimized small-scale purification kit incorporating the above features allows Car9-tagged proteins to be inexpensively recovered in minutes with better than 90% purity. The Car9 affinity purification technology should prove valuable for laboratory-scale applications requiring rapid access to milligram-quantities of proteins, and for preparative scale purification schemes where cost and productivity are important factors.

Hot melt extrusion has gained considerable attention as a novel technique for taste masking of bitter APIs. The aim of this study was to investigate whether hot melt extrusion could be used to develop taste masked formulations of isoniazid and also to evaluate and correlate different taste assessment methods Two polymers with different physico-chemical properties, Soluplus and Eudragit E-PO were chosen as carriers for the drug. Eudragit E-PO has already been widely used for taste masking due to its selective release properties, while Soluplus has not been studied in this regard but provides a useful comparator of a polymer that should release the drug reasonably efficiently. Polymeric formulations of isoniazid were produced with drug loadings of 20% and 30% w/w. The solid state characteristics of the formulations were assessed by differential scanning calorimetry and powder X-ray diffraction. The taste of isoniazid was assessed using the rodent Brief Access Taste Aversion (BATA) model, while formulations were assessed using the electronic tongue and dissolution under simulated oral conditions. Investigation into the drug loading effect with these two polymers showed that all Soluplus based extrudates with drug loading up to 30% w/w were fully amorphous while Eudragit E-PO based extrudates contained crystalline drug as demonstrated by both DSC and PXRD, dependent on loading. BATA testing of isoniazid gave an IC

New Findings What is the central question of this study? Previous evidence shows that some patients and mouse models carrying mutations in the methyl CpG binding protein-2 (MECP2) gene are overweight. However, the underlying mechanism associated with this phenotype has not been fully elucidated. What is the main finding and its importance? Using Mecp2-null mice, we found that the absence of methyl CpG binding protein-2 produces a deregulation in leptin signalling and alters the expression of key genes involved in body weight control. These results allow us to gain insight into the cellular mechanisms associated with leptin resistance and obesity. Methyl CpG binding protein-2 (MECP2) is a chromatin-remodelling factor with a dual role in gene expression. Evidence from patients carrying MECP2 mutations and from transgenic mouse models demonstrates that this protein is involved in the control of body weight. However, the mechanism for this has not been fully elucidated. To address this, we used a previously characterized Mecp2-null mouse model and found that the increase in body weight is associated with an increased amount of adipose tissue and high leptin levels. Appropriate body weight control requires the proper expression of pro-opiomelanocortin (Pomc) and agouti-related peptide (Agrp), two neuropeptides essential for satiety and appetite signals, respectively. Our results show that in the absence of Mecp2, Pomc and Agrp mRNA expression are altered, and the mice are leptin resistant. To determine the mechanism underlying the defective leptin sensing, we evaluated the expression of genes and the post-translational modifications associated with leptin signalling, which are fundamental to Pomc and Agrp transcriptional control and proper leptin response. We found a decrease in the phosphorylation level of Akt and its target protein Foxo1, which indicate an alteration in leptin-induced signal transduction. Our results demonstrate that the absence of Mecp2 disrupted body weight balance by altering post-translational modifications in leptin-signalling components that regulate Pomc and Agrp expression.

In biological systems, intercellular communication is mediated by membrane proteins and ion channels that regulate traffic of ions and small molecules across cell membranes. A bioelectronic device with ion channels that control ionic flow across a supported lipid bilayer (SLB) should therefore be ideal for interfacing with biological systems. Here, we demonstrate a biotic–abiotic bioprotonic device with Pd contacts that regulates proton (H+) flow across an SLB incorporating the ion channels Gramicidin A (gA) and Alamethicin (ALM). We model the device characteristics using the Goldman–Hodgkin–Katz (GHK) solution to the Nernst–Planck equation for transport across the membrane. We derive the permeability for an SLB integrating gA and ALM and demonstrate pH control as a function of applied voltage and membrane permeability. This work opens the door to integrating more complex H+ channels at the Pd contact interface to produce responsive biotic–abiotic devices with increased functionality., Conventional electronics use electrons as charge carriers whereas biological systems use ions, confounding integration of electronics with biology. Here the authors show voltage-regulated flow of protons across a supported lipid bilayer using the ion channel Gramicidin A and the voltage-gated ion channel Alamethicin.

Taste evaluation is a crucial factor for determining acceptance of medicines by patients. The human taste panel test is the main method used to establish the overall palatability and acceptability of a drug product to a patient towards the end of development. Non-human in vitro and in vivo taste-evaluation tools are very useful for pre-formulation, quality control and screening of formulations. These non-human taste assessment tools can be used to evaluate all aspects of taste quality. The focus of this review is bitterness because it is a key aspect of taste in association with the development of medicines. In this review, recent in vitro (analytical) and in vivo (non-human) tools are described for the assessment of the bitter taste of medicines. Their correlations with human taste data are critically discussed. The potential for their use in early screening of the taste of active pharmaceutical ingredients (APIs) to expedite paediatric formulation development is also considered.

Oxidative stress plays a crucial role in the pathogenesis of cardiovascular diseases such as myocardial infarction, hypertrophy and heart failure. ROS can induce a variety of DNA lesions in nucleus and mitochondria. However, quantitative analyses of these DNA lesions require methodical approaches that can discriminate between nuclear and mitochondrial DNA (mtDNA) lesions. In this study, we aimed to apply a PCR-based (QPCR) assay for the quantification of mtDNA lesions in cultured cardiomyocytes subjected to oxidative stress. In this assay, lesions that blocks the progression of the PCR polymerase result in decreased amplification of the target sequence, giving a relative measure of the lesions present. H9c2 embryonic rat cardiomyocytes cultures were treated for 1 h with increasing concentrations of H2O2 followed by DNA isolation and QPCR analysis. Compared to untreated cells, cells treated with 75, 100 and 200 µM of H2O2 showed a significant 60%, 80% and 90% reduction in the amplification of a mtDNA targe...

Methyl CpG binding protein-2 (MECP2) is a chromatin-remodelling factor with a dual role in gene expression. Evidence from patients carrying MECP2 mutations and from transgenic mouse models demonstrates that this protein is involved in the control of body weight. However, the mechanism for this has not been fully elucidated. To address this, we used a previously characterized Mecp2-null mouse model and found that the increase in body weight is associated with an increased amount of adipose tissue and high leptin levels. Appropriate body weight control requires the proper expression of pro-opiomelanocortin (Pomc) and agouti-related peptide (Agrp), two neuropeptides essential for satiety and appetite signals, respectively. Our results show that in the absence of Mecp2, Pomc and Agrp mRNA expression are altered, and the mice are leptin resistant. To determine the mechanism underlying the defective leptin sensing, we evaluated the expression of genes and the post-translational modifications associated with leptin signalling, which are fundamental to Pomc and Agrp transcriptional control and proper leptin response. We found a decrease in the phosphorylation level of Akt and its target protein Foxo1, which indicate an alteration in leptin-induced signal transduction. Our results demonstrate that the absence of Mecp2 disrupted body weight balance by altering post-translational modifications in leptin-signalling components that regulate Pomc and Agrp expression.

Mitogen activated protein kinases (MAPKs) play an important role in cell grow, proliferation and apoptosis in the heart. The MAPK family involves three major subgroups including extracellular signal-regulated protein kinase (ERK1/2), p38, and c-jun N-terminal kinases (JNK). Despite many studies demonstrating anti-hypetrophic action of AMP-kinase (AMPK), a metabolic sensor regulating energy metabolism, the relationship between AMPK activation and MAPKs is not clear yet. We hypothesize that beneficial effects of AMPK are mediated, at least in part, through modification of MAPKs activation. Experiments were performed on H9c2 myoblastic rat cardiomyocytes incubated at 370C with 95% air and 5% CO2. Hypertrophy was induced by treatment of the cells with 200 nM angiotensin II (Ang II, a peptide hormone stimulating hypertrophy) or 10 μM phenylephrine (PE, the α1-adrenergic receptor agonist). First, we determined time-course activation (phosphorylation) of ERK1/2, p38 and JNK in response to Ang II and PE. Second, ...

Background: Previous studies indicate that inhibition of JNK activation during heart reperfusion reduces cell death and infarct size. However, the studies could not eliminate off-target effects due...

Rett syndrome (RTT) is a disorder that affects patients' ability to communicate, move and behave. RTT patients are characterized by impaired language, stereotypic behaviors, frequent seizures, ataxia and sleep disturbances, with the onset of symptoms occurring after a period of seemingly normal development. RTT is caused by mutations in methyl-CpG binding protein 2 (MECP2), an X-chromosome gene encoding for MeCP2, a protein that regulates gene expression. MECP2 generates two alternative splice variants encoding two protein isoforms that differ only in the N-terminus. Although no functional differences have been identified for these splice variants, it has been suggested that the RTT phenotype may occur in the presence of a functional MeCP2-e2 protein. This suggests that the two isoforms might be functionally distinct. Supporting this notion, the two variants show regional and age-related differences in transcript abundance. Here, we show that transgenic expression of either the MeCP2-e1 or MeCP2-e2 splice variant results in prevention of development of RTT-like phenotypic manifestations in a mouse model lacking Mecp2. Our results indicate that the two MeCP2 splice variants can substitute for each other and fulfill the basic functions of MeCP2 in the mouse brain.

Uno de los problemas fundamentales de los algoritmos genéticos (AG) es la convergencia prematura a un óptimo local, debido principalmente a que los mejores individuos tienden a adueñarse de las características genéticas de la población, disminuyéndose la diversidad. Además, cuando la representación cromosómica es lineal, el cruzamiento es sensible a la codificación, ya que los extremos en este tipo de cromosoma pueden cambiar, con una probabilidad muy baja, sólo si son mutados. En este trabajo se aplica al problema de planificación de unidades térmicas de generación. Un AG que utiliza un operador determinista en la selección de individuos, donde se permite a individuos menos aptos perdurar de una generación a otra y un operador de cruce, llamado Cruce Anular, para generar nuevos individuos. Con ambos mecanismos se permite una mayor diversidad de la población y que el algoritmo sea menos dependiente de la codificación del cromosoma. Estos operadores garantizan la convergencia a una solución óptima, pero no garantiza rapidez de la convergencia. Sin embargo, los resultados obtenidos muestran que estos operadores alcanzan una convergencia más rápida y de mejor calidad que cuando se usan operadores estándares.

The technique of chromatofocusing was applied to the characterization and purification of three bacteriophages that are routinely used for testing virus filters: phiX174, PR772, and PP7. Chemically well-defined eluent buffers were used, instead of the more commonly used chromatofocusing polyampholyte buffers. Chromatographic column packings were selected to minimize band broadening by confining bacteriophage adsorption solely to the exterior particle surface. Under the conditions used it was determined that bacteriophages could be made to focus into narrow bands in a retained pH gradient with recoveries of live phage that ranged from 15 to nearly 100% as determined by a plaque-forming assay. Retention times and apparent isoelectric point data were obtained for samples consisting either of purified bacteriophage, or samples consisting of crude preparations of bacteriophages containing host cell impurities. Isoelectric point estimates were obtained using modified, previously described models. The results obtained suggest that chromatofocusing is a simple and rapid method for obtaining approximate isoelectric points for bacteriophages and probably other types of viruses. It is also likely a useful method for purifying these materials.

The inadvertent pH transient produced when a stepwise change in salt concentration is used as the eluent in ion-exchange chromatography was studied theoretically using a local-equilibrium theory and experimentally using both strong-base and weak-base anion-exchange column packings. The accuracy of the local-equilibrium theory was verified by comparing it to a full numerical solution of the governing partial differential equations obtained using the method of characteristics. The predictions from the local-equilibrium theory were observed to largely agree with experimental results. Detailed comparisons of experimental results and the local-equilibrium theory permitted the observed trends for the pH transients to be interpreted in terms of the physical properties of the column packing and mobile phase. The results of this study are useful for the design of ion-exchange processes using salt gradient elution where it is desired to limit the exposure of eluted proteins to the inadvertent pH transient caused by the salt gradient.

The main purpose of this research was to evaluate the effects of two novel benzazolo[3,2-a]quinolinium salts (ABQ-48 and NBQ48) on lymphoma cells (TOLEDO). The cationic nature of these BQS can facilitate its interaction with cell organelles such as mitochondria and DNA. To determine its potential cytotoxic effects the compounds were screened through the NCI 60 cell line protocol which determines the cell viability inhibitory activity in various cancer histological types. The IC50 dose for these compounds was determined and used to assess their apoptosis induction capacity evaluating apoptosis hallmark events such as DNA Fragmentation, Caspase 3&7 activators and mitochondrial membrane permeabilization. Additionally cell reduction potential of the compounds was measured. Results from the NCI 60 cell line protocol demonstrated the toxicity of BQS in multiple cancer types including breast and colon cancer cells. Preliminary results indicated mitochondrial membrane permeabilization on cells treated with NBQ48 (51.3%) and ABQ48 (57.67%) comparable to the positive controls camptothecin (51.6%) and valinomycin (55.3%). Treated cells also presented DNA fragmentation with NBQ48 and ABQ48 (28%) comparable to the positive control 37%. Preliminary data for caspases 3&7 activation strongly suggest an intrinsic apoptosis pathway. Analysis of the reduction of nitro substituted compound NBQ 48 to the amino substituted ABQ 48 on treated cells was determined by measuring an increment on fluorescence emission, characteristic of an amino specie. In conclusion, the study provides evidence of the induction of key apoptotic events as part of the mechanism of action of these novel BQS. Citation Format: Karoline Rios-Rodriguez, Jessica Soto, Christian Velez, Osvaldo Cox, Juan P. Rivera, Beatriz Zayas. Toxicity screening, apoptosis hallmark events and nitro reduction of novel quinolinium salts (BQS) on lymphoma cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1586. doi:10.1158/1538-7445.AM2014-1586

Obtaining a better understanding of the adsorption behavior of polymeric nanomedicines is important to properly assess their distribution and fate and to develop successful strategies for minimizing their distribution in the environment. In this study, the adsorption and removal dynamics of a model polymeric nanomedicine of systematically varied sizes – levofloxacin loaded poly(ethyleneglycol-b-e-caprolactone) – on and from silica surfaces are investigated using a quartz crystal microbalance with dissipation (QCM-D). For all the sizes of the nanomedicine investigated (90 nm, 110 nm, 149 nm, 174 nm, 207 nm, and 305 nm), the adsorbate mass on the silica followed a roughly exponential trend with respect to time during the exposure stage, suggesting first-order adsorption kinetics. The adsorption rate constant decreased with the increasing particle size. Furthermore, we have developed a modified Leveque equation to describe the mass transport and adsorption behavior of the nanoparticulate dispersion inside the QCM-D chamber. The derivation involved the application of a bipolar coordinate system to the continuity, Navier–Stokes, and convective–diffusion equations. The adsorption rate constants calculated using the derived equation were found to match the experimental results well. The derived equation is important not only in the field of environmental science but also in many other fields as QCM-D is heavily used to characterize the dynamic adsorption behavior of various types of materials including polymers, proteins, and nanoparticles.