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The present work reports the antibacterial activity againstPseudomonasaeruginosaof a nanocomposite made of zinc oxide nanoparticles dispersed in a poly(acrylamide-co-hydroxyethylmethacrylate) matrix (PAAm-Hema-ZnONPs). Thein situsynthesis of ZnONPs inside of the PAAm-Hema crosslinked network is described. Moreover, the physicochemical properties of the PAAm-Hema-ZnONPs nanocomposite are analyzed. The results confirm that the PAAm-Hema hydrogel provides an excellent scaffold to generate ZnONPs. The presence of ZnONPs inside the hydrogel was confirmed by UV-visible (band at 320 nm), by Infrared spectroscopy (peak at 470 cm-1), SEM, and TEM images. The presence of NPs in PAAm-Hema diminish the swelling percentage by 70%, and the Young modulus by 33.7%, compared with pristine hydrogel. The 75% of ZnONPs are released from the nanocomposite after 48 h of spontaneous diffusion, allowing the use of the nanocomposite as an antibacterial agent.In vitro, the agar diffusion test presents an inhibition halo againstP. aeruginosabacteria 50% higher than the unloaded hydrogel. Also, the PAAm-Hema-ZnONPs live/dead test shows 54% of dead cells more than the hydrogel. These results suggest that the easy, one-step way generated composites can be used in biomedical applications as antimicrobial agents.

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Quasi-periodic moiré patterns and their effect on electronic properties of twisted bilayer graphene have been intensely studied. At small twist angle θ, due to atomic reconstruction, the moiré superlattice morphs into a network of narrow domain walls separating micron-scale AB and BA stacking regions. We use scanning probe photocurrent imaging to resolve nanoscale variations of the Seebeck coefficient occurring at these domain walls. The observed features become enhanced in a range of mid-infrared frequencies where the hexagonal boron nitride substrate is optically hyperbolic. Our results illustrate the capabilities of the nano-photocurrent technique for probing nanoscale electronic inhomogeneities in two-dimensional materials.

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Psychological approaches to the study of armed conflict have focused on analyzing post-traumatic stress outcomes, and on evaluating the intensity of exposure to violent confrontation. Nevertheless, psychometrically valid tools required for measuring these traumatic experiences are scarce To validate the Extreme Experiences scale (EX2) for armed conflict contexts for its use in Colombia, and to provide a framework for validation in conflict contexts around the world This Cross-sectional aims to validate the scale with 187 participants, study of validate with 187 participants, comprising population with high exposure to conflict (former combatants and a set of armed conflict victims) and low conflict-exposed individuals (control group). Structures of two domains and 18 items were confirmed: Direct Extreme Experiences (dEX2) and Indirect Extreme Experiences (iEX2); these dimensions were also validated by expert judgment, producing 14-item version. Good levels of internal consistency were found, with a KR-20 of 0.80 for the 18-item version, and 0.77 for the 14-item. The scale differentiates between population with 'high exposure to conflict' from population with 'low exposure' (dnp > 0.5 and area under the ROC >0.90). The scale scores have significant correlation with some mental health constructs. The EX2 scale has good internal consistency, as well as structural validity with regard to exposed groups. This scale can be potentially validated for its use in countries with armed confrontation history. In future versions, the scale may include additional items in order to improve content validity.

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INTRODUCTION: The identification of pre-frailty and frailty syndrome in older adults is important due to its association with the development of disability. It is a priority problem for health systems and quality of life of older adults, caregivers, and relatives. OBJECTIVE: To determine the prevalence and associated factors of pre-frailty and frailty syndrome in indigenous older adults from Colombia. MATERIAL AND METHOD: A cross-sectional study was conducted that included 540 indigenous over 60 years of age who belong to the 13 sub-regions of the Obando province in Nariño, Colombia. The prevalence of frailty and pre-frailty syndrome was determined, we evaluated sociodemographic variables, cognitive deterioration, functionality, and the presence of different morbidities. Associations were estimated using multivariate multinomial logistic regression models. RESULTS: The mean age was 70.68 (SD 6.86). The prevalence of frailty syndrome was 32.4%, and pre-frailty syndrome was 58.7%. Having depressive symptoms, those with altered functional dependence according to the Barthel index, and those who reported having arthrosis or arthritis, showed an association with frailty syndrome. CONCLUSION: This analysis shows a high prevalence of frailty syndrome in the population of indigenous older adults. This was similar to that reported in other countries. Frailty has a great impact on health due to its strong association with musculoskeletal diseases, depression, and disability.

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Biofilm Formation is a survival strategy for microorganisms to adapt to their environment. Microbial cells in biofilm become tolerant and resistant to antibiotics and immune responses, increasing the difficulties for the clinical treatment of microbial infections. The surface chemistry and the micro/nano-topography of solid interfaces play a major role in mediating microorganism activity and adhesion. The effect of the surface chemical composition and topography on the adhesion and viability of Pseudomonas aeruginosa was studied. Polymeric (polyethylene terephthalate) surfaces were covered with a conducting polymer (polyaniline, PANI) film by in-situ polymerization and microstructured by Direct Laser Interference Patterning (DLIP). The viability of Pseudomonas aeruginosa on the different surfaces was investigated. The physicochemical properties of the surfaces were characterized by water contact angle measurements, scanning electron microscopy and atomic force microscopy. Bacterial biofilms were imaged by atomic force and scanning electron microscopies. The bacterial viability decreased on PANI compared with the substrate (polyethylene terephthalate) and it decreased even more upon micro-structuring the PANI films. In addition, the biofilm reduction could be improved using polymers with different chemical composition and/or the same polymer with different topographies. Both methods presented diminish the bacterial attachment and biofilm formation. These findings present a high impact related to materials for biomedical engineer applications regarding medical devices, as prostheses or catheters.

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The human body combats infection and promotes wound healing through the remarkable process of inflammation. Inflammation is characterized by the recruitment of stromal cell activity including recruitment of immune cells and induction of angiogenesis. These cellular processes are regulated by a class of soluble molecules called cytokines. Based on function, cell target, and structure, cytokines are subdivided into several classes including: interleukins, chemokines, and lymphokines. While cytokines regulate normal physiological processes, chronic deregulation of cytokine expression and activity contributes to cancer in many ways. Gene polymorphisms of all types of cytokines are associated with risk of disease development. Deregulation RNA and protein expression of interleukins, chemokines, and lymphokines have been detected in many solid tumors and hematopoetic malignancies, correlating with poor patient prognosis. The current body of literature suggests that in some tumor types, interleukins and chemokines work against the human body by signaling to cancer cells and remodeling the local microenvironment to support the growth, survival, and invasion of primary tumors and enhance metastatic colonization. Some lymphokines are downregulated to suppress tumor progression by enhancing cytotoxic T cell activity and inhibiting tumor cell survival. In this review, we will describe the structure/function of several cytokine families and review our current understanding on the roles and mechanisms of cytokines in tumor progression. In addition, we will also discuss strategies for exploiting the expression and activity of cytokines in therapeutic intervention.

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Oral administration of specific egg yolk immunoglobulin (IgY) is effective against a number of gastrointestinal pathogens. However, the activity of orally administered IgY is reduced rapidly, since IgY is sensitive to pepsin and low pH. In this study, hydrogels containing acrylamide and acrylic acid were synthesized and used to encapsulate IgY. The capacity of these structures to load, protect and release IgY and the interaction between IgY and hydrogels by FTIR spectroscopy were studied. The particle size and swelling percentage of hydrogels were highly dependent on the pH of the buffer solution. As expected, pH-sensitive hydrogels had a high IgY loading percentage (99.2 ± 12.9 mg IgY/mg hydrogel) at pH 7.4. It means that each gel piece incorporated approximately 8.4 ± 1.1 mg IgY. The results showed that the hydrogels could efficiently incorporate IgY and retain it inside the polymer network at pH <2.2. However, IgY was slowly released at basic pH and a high percentage remained inside. The IR spectra show that IgY interacts with the hydrogel in its network with extended hydrogen bonds. The present study demonstrates that hydrogels particles can efficiently incorporate the IgY but cannot show a controlled and sustained release of IgY in simulated intestinal fluid probably due to hydrophobic interactions with the polymer network. The stability of IgY in simulated gastric fluid was greatly improved by encapsulation in hydrogels. This approach provides information about a novelty method for delivery of IgY for the prevention and control of enteric diseases.

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The literature on GWAS (genome-wide association studies) data suggests that very large sample sizes (for example, 50,000 cases and 50,000 controls) may be required to detect significant associations of genomic regions for complex disorders such as Alzheimer's disease (AD). Because of the challenges of obtaining such large cohorts, we describe here a novel sequential strategy that combines pooling of DNA and bootstrapping (pbGWAS) in order to significantly increase the statistical power and exponentially reduce expenses. We applied this method to a very homogeneous sample of patients belonging to a unique and clinically well-characterized multigenerational pedigree with one of the most severe forms of early onset AD, carrying the PSEN1 p.Glu280Ala mutation (often referred to as E280A mutation), which originated as a consequence of a founder effect. In this cohort, we identified novel loci genome-wide significantly associated as modifiers of the age of onset of AD (CD44, rs187116, P=1.29 × 10⁻¹²; NPHP1, rs10173717, P=1.74 × 10⁻¹²; CADPS2, rs3757536, P=1.54 × 10⁻¹°; GREM2, rs12129547, P=1.69 × 10⁻¹³, among others) as well as other loci known to be associated with AD. Regions identified by pbGWAS were confirmed by subsequent individual genotyping. The pbGWAS methodology and the genes it targeted could provide important insights in determining the genetic causes of AD and other complex conditions.

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A direct study of the shape, size and connectivity of nonordered pores in carbon materials is particularly challenging. A new method that allows direct three-dimensional (3D) investigations of mesopores in monolithic carbon materials and quantitative characterization of their physical properties (surface area and pore size distribution) is reported. Focused ion beam (FIB) nanotomography technique is performed by combination of focused ion beam and scanning electron microscope. Porous monolithic carbon is produced by carbonization of a resorcinol-formaldehyde gel in the presence of a cationic polyelectrolyte as a pore stabilizer.

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We developed a method to graft a tripeptide (glutathione) onto 5-hydroxy-1,4-naphthoquinone, an electropolymerizable molecule. The resulting thin conducting polymer presents a well-defined and stable electroactivity in neutral buffered solution, due to the embedded quinone group, and is able to covalently graft amino-modified DNA probe strands. It is shown that the bioelectrode presents positive current change following DNA hybridization. This makes a "signal-on" direct electrochemical DNA sensor. The results were obtained with low target concentration (50nM) and the selectivity is excellent as a single-mismatch sequence can be discriminated from the full-complementary target.

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Introducción. Los signos clínicos de la arteriopatía cerebral autosómica dominante con infartos subcorticales y leucoencefalopatía (CADASIL) se expresan principalmente en el sistema nervioso y recientemente se han descrito en la retina. Objetivo. Establecer la prevalencia y el riesgo de enfermedad periodontal en sujetos de familias con historia de presencia de mutación CADASIL del departamento de Antioquia, Colombia. Sujetos y métodos. Se realizó un estudio transversal (crosssectional), con asignación al grupo CADASIL y grupo control según genotipificación de cada sujeto para la mutación R1031C y C455R en Notch3. Cada participante firmó voluntariamente el consentimiento informado y recibió evaluación clínica neurológica,neuropsicológica y periodontal. Resultados. No existieron diferencias significativas entre los dos grupos según edad, sexo, escolaridad, tabaquismo, estado cognitivo, estado funcional y presencia de dientes naturales. La frecuencia de placa blanda, gingivitis y enfermedad periodontal fue significativamente mayor en el grupo de portadores de mutación CADASILque en el grupo control. El grupo CADASIL presentó seis veces más riesgo de tener placa blanda mayor o igual al 20% que el grupo control. La prevalencia de gingivitis mayor o igual al 10% se presentó en el total de los integrantes del grupo CADASIL. Las personas que conformaron el grupo CADASIL presentaron cinco veces más riesgo de tener enfermedad periodontal que el grupo control. Conclusión. Las personas portadoras de mutación CADASIL presentan mayor prevalencia y riesgo de enfermedad periodontal (AU)

Introduction. The clinical signs of cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) are expressed mainly in the nervous system and recently reports also situate them in the retina. Aim. To determine the prevalence and risk of periodontal disease in subjects from families with a history of CADASIL mutation in the department of Antioquia, Colombia. Subjects and methods. A cross-sectional study was conducted, with subjects being assigned to the CADASIL group or a control group according to genotyping for the R1031C AND C455R mutation in Notch3. Each participant voluntarily signed the informed consent document and was submitted to neurological, neuropsychological and periodontal evaluation. Results. No significant differences were found between the two groups according to age, sex, schooling, tobacco smoking, cognitive status, functional status and the presence of natural teeth. The frequency of soft plaque, gingivitis and periodontal disease was significantly higher in the group of carriers of the CADASIL mutation than in the control group. The CADASIL group had six times more risk of having soft plaque above or equal to 20% than the control group. Prevalence of gingivitis above or equal to 10% was observed in all the members of the CADASIL group. The people in the CADASIL group had five times more risk of suffering periodontal disease than the control group. Conclusions. Carriers of the CADASIL mutation displayed a higher prevalence and risk of periodontal disease (AU)

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INTRODUCTION: The clinical signs of cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) are expressed mainly in the nervous system and recently reports also situate them in the retina. AIM: To determine the prevalence and risk of periodontal disease in subjects from families with a history of CADASIL mutation in the department of Antioquia, Colombia. SUBJECTS AND METHODS: A cross-sectional study was conducted, with subjects being assigned to the CADASIL group or a control group according to genotyping for the R1031C and C455R mutation in Notch3. Each participant voluntarily signed the informed consent document and was submitted to neurological, neuropsychological and periodontal evaluation. RESULTS: No significant differences were found between the two groups according to age, sex, schooling, tobacco smoking, cognitive status, functional status and the presence of natural teeth. The frequency of soft plaque, gingivitis and periodontal disease was significantly higher in the group of carriers of the CADASIL mutation than in the control group. The CADASIL group had six times more risk of having soft plaque above or equal to 20% than the control group. Prevalence of gingivitis above or equal to 10% was observed in all the members of the CADASIL group. The people in the CADASIL group had five times more risk of suffering periodontal disease than the control group. CONCLUSIONS: Carriers of the CADASIL mutation displayed a higher prevalence and risk of periodontal disease.

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Introducción. La enfermedad de Parkinson (EP) es el trastorno neurodegenerativo más común después de la enfermedad de Alzheimer, y se caracteriza por temblor, bradicinesia, rigidez e inestabilidad postural. El trastorno cognitivo más común es disfunción ejecutiva, aunque también se han informado déficit globales asociados al inicio tardío de la enfermedad. Objetivos. Describir y comparar el desempeño cognitivo en tres grupos con EP y uno con parkinsonismo. Pacientes y métodos. A 175 pacientes con EP idiopática y parkinsonismo se les realizó una valoración neurológica y neuropsicológica. El análisis de datos se hizo comparando resultados de las pruebas para cuatro grupos: tres con EP (edad de inicio: juvenil, del adulto y tardía) y uno con parkinsonismo, y controlando por edad, escolaridad y tiempo de evolución. Resultados. En el grupo conEP juvenil se encontró alteración en el número de intrusiones en memoria verbal; en los de EP del adulto y EP tardía, se encontró alteración en el tiempo en ejecución continua visual. Comparados entre sí los grupos y controlando por edad, las diferencias desaparecieron. El grupo con parkinsonismo obtuvo resultados inferiores a todos los grupos con EP para la mayoría de variables cognitivas y funcionales. Conclusiones. La EP idiopática no sería causante de deterioro cognitivo múltiple, sino de una alteración específica, principalmente en velocidad de procesamiento y evocación de la información. La edad de inicio no sería un factor decisivo en el grado de deterioro del funcionamiento cognitivo; sólo existe un deterioro cognitivo importante en el grupo con parkinsonismo (AU)

Introduction. Parkinson’s disease (PD) is the second most common neurodegenerative disorder after Alzheimer’s disease, and it is characterised by tremor, bradykinesia, rigidity and postural instability. The most frequent cognitive disorder is executive dysfunction, although global deficits associated to late onset of the disease have also been reported. Aims. To describe and to compare cognitive performance in three groups with PD and one with Parkinsonism. Patients and methods. A neurological and neuropsychological evaluation was carried out on 175 patients with idiopathic PD and Parkinsonism. The data analysis was performed by comparing the results of the tests carried out on the four groups: three with PD (age of onset: juvenile, adult and late) and one with Parkinsonism, while controlling for age, schooling and time of progression. Results. In the juvenile PD group, alterations were observed in the number of intrusions in verbal memory; in the adult PD and late PD groups, there were alterations in time in continuous visual execution. These differences disappeared when the groups were compared to each other while also controlling for age. The Parkinsonism group obtained results that were lower than those of all the groups with PD for most of the cognitive and functional variables. Conclusions. Idiopathic PD would not be the cause of multiple cognitive impairment, but of a specific alteration, mainly involving the speed of processing and information recall. Age of onset would not be a decisive factor in the degree of impairment of cognitive functioning; important cognitive impairment was only present in the group with Parkinsonism (AU)

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INTRODUCTION: Parkinson's disease (PD) is the second most common neurodegenerative disorder after Alzheimer's disease, and it is characterised by tremor, bradykinesia, rigidity and postural instability. The most frequent cognitive disorder is executive dysfunction, although global deficits associated to late onset of the disease have also been reported. AIMS: To describe and to compare cognitive performance in three groups with PD and one with Parkinsonism. PATIENTS AND METHODS: A neurological and neuropsychological evaluation was carried out on 175 patients with idiopathic PD and Parkinsonism. The data analysis was performed by comparing the results of the tests carried out on the four groups: three with PD (age of onset: juvenile, adult and late) and one with Parkinsonism, while controlling for age, schooling and time of progression. RESULTS: In the juvenile PD group, alterations were observed in the number of intrusions in verbal memory; in the adult PD and late PD groups, there were alterations in time in continuous visual execution. These differences disappeared when the groups were compared to each other while also controlling for age. The Parkinsonism group obtained results that were lower than those of all the groups with PD for most of the cognitive and functional variables. CONCLUSIONS: Idiopathic PD would not be the cause of multiple cognitive impairment, but of a specific alteration, mainly involving the speed of processing and information recall. Age of onset would not be a decisive factor in the degree of impairment of cognitive functioning; important cognitive impairment was only present in the group with Parkinsonism.

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INTRODUCTION: The Wender-Utah Rating Scale (WURS) has been used for retrospective screening of attention deficit hyperactivity disorders (ADHD) symptoms and its comorbidities. AIM: To establish the ADHD behavioral phenotype dimensions of adults from 140 Antioquian families with genetic segregation for ADHD diagnosis, using the WURS -Spanish version. SUBJECTS AND METHODS: 392 adults from both genders, belonging to nuclear and multigenerational families with one or more ADHD affected members were selected. The Composite International Diagnostic Interview (CIDI) for mental disorder was administered to establish the gold standard diagnosis of ADHD through the long life. All participants fulfill the WURS. Exploratory and confirmatory factor analyses were done to determine the behavioral dimensions of the ADHD phenotype. RESULTS: A factor structure of four dimensions was derived, measuring behavioral decontrol, hyperactivity, inattention and anxiety, and which explained the 60% of the total variance. CONCLUSIONS: The behavioral adult ADHD phenotype in the Antioquian families was conformed by four dimensions, which could be used in heritability and linkage future studies.

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INTRODUCTION: Intrusive errors in verbal memory tests could be considered as a preclinical marker of familial Alzheimer disease (AD). AIMS. To analyze and to compare the number and types of intrusive errors in the CERAD verbal memory test, administered to a genealogy of affected by familial AD, with E280A presenilin-1 mutation. PATIENTS AND METHODS: Sample was constituted by 30 asymptomatic non-carriers (ANC), 39 non-demented carriers (NDC) and 21 demented carriers (DC). CERAD verbal memory test was administered to the sample. Comparisons, with non parametric Kruskal-Wallis' analysis, were done. RESULTS: NDC participants presented more intrusive errors than ANC group in the first and second trials and in the delay recall of the memory task; also they had more intrusive errors than the DC patients in intrusive errors of the first trial and delay recall of the same task. The ANC and DC groups had significantly more intrusions only in third trial. CONCLUSION: Intrusive errors could be considered as a cognitive preclinical marker for familial AD.

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