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CCB. Artículos indexados en Scopus

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Breaking down barriers to surgical learning in times of COVID-19: an initiative of future surgeons

Ortega Sierra, Michael Gregorio | 2021

ESAT-6 and Ag85A Synthetic Peptides as Candidates for an Immunodiagnostic Test in Children with a Clinical Suspicion of Tuberculosis

Araujo, Zaida | 2021

Background. Tuberculosis (TB) is being underdetected in children as most are smear-negative. This work was aimed at evaluating ESAT-6 and Ag85A synthetic peptides’ serodiagnostic potential for diagnosing children having a clinical suspicion of TB. Methods. The study involved 438 children: 77 Creole nonindigenous (13 suspected of having TB and 64 healthy ones) and 361 Warao indigenous children (39 suspected of TB and 322 healthy children). The approach’s diagnostic information was compared using operational characteristics and receiver-operating characteristic (ROC) curves. Results. Ag85A P-29879 had 94.6% sensitivity (: 0.651 to 0.819 95% CI) in indigenous children. ESAT-6 P-12036 and P-12037 had 100% and 92.3% of sensitivity (: 0.929: 0.846 to 0.975 95% CI and 0.791: 63.9 to 98.7 95% CI, respectively) in Creole children. ESAT-6 peptides also allowed a differentiation between children with TB and healthy ones. Conclusions. Further validation of this approach could lead to developing a complementary tool for rapid TB diagnosis in children.

Machine learning models to select potential inhibitors of acetylcholinesterase activity from SistematX: a natural products database

Herrera-Acevedo, C. | 2021

Alzheimer's disease is the most common form of dementia, representing 60-70% of dementia cases. The enzyme acetylcholinesterase (AChE) cleaves the ester bonds in acetylcholine and plays an important role in the termination of acetylcholine activity at cholinergic synapses in various regions of the nervous system. The inhibition of acetylcholinesterase is frequently used to treat Alzheimer's disease. In this study, a merged BindingDB and ChEMBL dataset containing molecules with reported half-maximal inhibitory concentration (IC50) values for AChE (7032 molecules) was used to build machine learning classification models for selecting potential AChE inhibitors from the SistematX dataset (8593 secondary metabolites). A total of seven fivefold models with accuracy above 80% after cross-validation were obtained using three types of molecular descriptors (VolSurf, DRAGON 5.0, and bit-based fingerprints). A total of 521 secondary metabolites (6.1%) were classified as active in this stage. Subsequently, virtual screening was performed, and 25 secondary metabolites were identified as potential inhibitors of AChE. Separately, the crystal structure of AChE in complex with (-)-galantamine was used to perform molecular docking calculations with the entire SistematX dataset. Consensus analysis of both methodologies was performed. Only eight structures achieved combined probability values above 0.5. Finally, two sesquiterpene lactones, structures 15 and 24, were predicted to be able to cross the blood-brain barrier, which was confirmed in the VolSurf+ quantitative model, revealing these two structures as the most promising secondary metabolites for AChE inhibition among the 8593 molecules tested. A consensus analysis of classification models and molecular docking calculations identified four potential inhibitors of acetylcholinesterase from the SistematX dataset (8593 structures)

International optimism: Correlates and consequences of dispositional optimism across 61 countries

Baranski, Erica | 2021

Objective: The current exploratory study sought to examine dispositional optimism, or the general expectation for positive outcomes, around the world. Method: Dispositional optimism and possible correlates were assessed across 61 countries (N = 15,185; mean age = 21.92; 77% female). Mean-level differences in optimism were computed along with their relationships with individual and country-level variables. Results: Worldwide, mean optimism levels were above the midpoint of the scale. Perhaps surprisingly, country-level optimism was negatively related to gross domestic product per capita, population density, and democratic norms and positively related to income inequality and perceived corruption. However, country-level optimism was positively related to projected economic improvement. Individual-level optimism was positively related to individual well-being within every country, although this relationship was less strong in countries with challenging economic and social circumstances. Conclusions: While individuals around the world are generally optimistic, societal characteristics appear to affect the degree to which their optimism is associated with psychological well-being, sometimes in seemingly anomalous ways

Identification of Multiple Blastocystis Subtypes in Domestic Animals From Colombia Using Amplicon-Based Next Generation Sequencing

Higuera, Adriana | 2021

Blastocystis is frequently reported in fecal samples from animals and humans worldwide, and a variety of subtypes (STs) have been observed in wild and domestic animals. In Colombia, few studies have focused on the transmission dynamics and epidemiological importance of Blastocystis in animals. In this study, we characterized the frequency and subtypes of Blastocystis in fecal samples of domestic animals including pigs, minipigs, cows, dogs, horses, goats, sheep, and llama from three departments of Colombia. Of the 118 fecal samples included in this study 81.4% (n = 96) were positive for Blastocystis using a PCR that amplifies a fragment of the small subunit ribosomal RNA (SSU rRNA) gene. PCR positive samples were sequenced by next generation amplicon sequencing (NGS) to determine subtypes. Eleven subtypes were detected, ten previously reported, ST5 (50.7%), ST10 (47.8%), ST25 (34.3%), ST26 (29.8%), ST21 (22.4%), ST23 (22.4%), ST1 (17.9%), ST14 (16.4%), ST24 (14.9%), ST3 (7.5%), and a novel subtype, named ST32 (3.0%). Mixed infection and/or intra -subtype variations were identified in most of the samples. Novel ST32 was observed in two samples from a goat and a cow. To support novel subtype designation, a MinION based sequencing strategy was used to generate the full-length of the SSU rRNA gene. Comparison of full-length nucleotide sequences with those from current valid subtypes supported the designation of ST32. This is the first study in Colombia using NGS to molecularly characterize subtypes of Blastocystis in farm animals. A great diversity of subtypes was observed in domestic animals including subtypes previously identified in humans. Additionally, subtype overlap between the different hosts examined in this study were observed. These findings highlight the presence of Blastocystis subtypes with zoonotic potential in farm animals indicating that farm animals could play a role in transmission to humans

Nanovaccines against animal pathogens: The latest findings

Celis Giraldo, Carmen Teresa | 2021

Nowadays, safe and efficacious vaccines represent powerful and cost-effective tools for global health and economic growth. In the veterinary field, these are undoubtedly key tools for improving productivity and fighting zoonoses. However, cases of persistent infections, rapidly evolving pathogens having high variability or emerging/re-emerging pathogens for which no effective vaccines have been developed point out the continuing need for new vaccine alternatives to control outbreaks. Most licensed vaccines have been successfully used for many years now; however, they have intrinsic limitations, such as variable efficacy, adverse effects, and some shortcomings. More effective adjuvants and novel delivery systems may foster real vaccine effectiveness and timely implementation. Emerging vaccine technologies involving nanoparticles such as self-assembling proteins, virus-like particles, liposomes, virosomes, and polymeric nanoparticles offer novel, safe, and high-potential approaches to address many vaccine development-related challenges. Nanotechnology is accelerating the evolution of vaccines because nanomaterials having encapsulation ability and very advantageous properties due to their size and surface area serve as effective vehicles for antigen delivery and immunostimulatory agents. This review discusses the requirements for an effective, broad-coverage-elicited immune response, the main nanoplatforms for producing it, and the latest nanovaccine applications for fighting animal pathogens.

The First Chemically-Synthesised, Highly Immunogenic Anti-SARS-CoV-2 Peptides in DNA Genotyped Aotus Monkeys for Human Use

Patarroyo, Manuel-Elkin | 2021

Thirty-five peptides selected from functionally-relevant SARS-CoV-2 spike (S), membrane (M), and envelope (E) proteins were suitably modified for immunising MHC class II (MHCII) DNA-genotyped Aotus monkeys and matched with HLA-DRβ1* molecules for use in humans. This was aimed at producing the first minimal subunit-based, chemically-synthesised, immunogenic molecules (COLSARSPROT) covering several HLA alleles. They were predicted to cover 48.25% of the world’s population for 6 weeks (short-term) and 33.65% for 15 weeks (long-lasting) as they induced very high immunofluorescent antibody (IFA) and ELISA titres against S, M and E parental native peptides, SARS-CoV-2 neutralising antibodies and host cell infection. The same immunological methods that led to identifying new peptides for inclusion in the COLSARSPROT mixture were used for antigenicity studies. Peptides were analysed with serum samples from patients suffering mild or severe SARS-CoV-2 infection, thereby increasing chemically-synthesised peptides’ potential coverage for the world populations up to 62.9%. These peptides’ 3D structural analysis (by 1H-NMR acquired at 600 to 900 MHz) suggested structural-functional immunological association. This first multi-protein, multi-epitope, minimal subunit-based, chemically-synthesised, highly immunogenic peptide mixture highlights such chemical synthesis methodology’s potential for rapidly obtaining very pure, highly reproducible, stable, cheap, easily-modifiable peptides for inducing immune protection against COVID-19, covering a substantial percentage of the human population

Application of proteomic to investigate the different degrees of meat tenderness in Nellore breed

Malheiros, J. M. | 2021

This study describes the association between meat tenderness and abundance of soluble muscle proteins in Nellore bulls (Bos indicus) using a proteomic approach. We evaluated shear force (SF) of Longissimus thoracis muscle 24 h after slaughter and selected three experimental groups of animals with moderately tender (TE; SF = 3.9 ± 0.7 kg), moderately tough (TO; SF = 5.6 ± 0.7 kg) and very tough meat (TO+; SF = 7.9 ± 1.4 kg). Proteome was investigated by two-dimensional electrophoresis (2D-PAGE) in combination with electrospray ionization-tandem mass spectrometry (ESI–MS/MS). The metabolic proteins triosephosphate isomerase (TPI1) and phosphoglucomutase 1 (PGM1), the structural protein profilin 1 (PFN1), and cytosol aminopeptidase (LAP3) were up-regulated (P < 0.05) in the TE meat group when compared to the TO and TO+ groups. Actin structural proteins (ACTA1, ACTB, and ACTG1), the oxidative stress protein peroxiredoxin (PRDX6, PRDX2, PRDX1, and PARK7), heat shock protein isoforms, and co-chaperones (CDC37 and STIP1) were up-regulated (P < 0.05) in the TO and TO+ meat groups. In addition, we also identified proteins PFN1, LAP3, PRDX1, PRDX2, HSPD1, and ARHGDIA to be associated with beef tenderness. The results reported herein demonstrated that meat tenderness in Nellore cattle depends on the modulation and expression of a set of proteins involved in different biological pathways.

Genetic diversity and population structure of Rhipicephalus sanguineus sensu lato across diferent regions of Colombia

Páez‑Triana, Luisa | 2021

Background: There has been a long-standing debate over the taxonomic status of Rhipicephalus sanguineus sensu lato. Different studies worldwide have reported the occurrence of different well-defined lineages, in addition to Rhipicephalus sanguineus sensu stricto. To date, there are very few studies examining the diverse aspects of this tick in Colombia. We assessed the population structure and genetic diversity of R. sanguineus s.l. in eight departmental regions across Colombia. Methods: A total of 170 ticks were collected from dogs in different departments of Colombia. All specimens were morphologically compatible with R. sanguineus s.l. and subjected to genetic analysis. DNA sequences were obtained for the 12S rDNA, cytochrome oxidase I (COI) and internal transcribed spacer 2 (ITS2) markers. A concatenated set of all mitochondrial markers was also constructed. Next, maximum likelihood phylogenetic trees were constructed using the sequences generated herein and sequences available in GenBank. Finally, we assessed different summary statistics and analysed population structure and divergence with Fst and Dxy and demographic changes with Tajima's D and Fu and Li’s statistical tests. Results: Analysis of the 12S rDNA and COI revealed that all R. sanguineus s.l. specimens collected across different regions of Colombia clustered within the tropical lineage. Micro-geographical analyses showed that the tick population from Amazonas formed a distinct cluster separated from the other sequences, with moderate Fst and Dxy values. However, no signs of a robust population structure were found within the country. The results of Fu’s FS tests, together with the haplotype networks and diversity values, signal a possible population expansion of this tick species in Colombia. Conclusions: Evidence provided herein supports the tropical lineage as the main circulating lineage in Colombia, exhibiting a general lack of genetic structure except for the Amazonas region

The impact of immigration on tuberculosis and HIV burden between Colombia and Venezuela and across frontier regions

Arenas Suarez, Nelson Enrique | 2021

Historically, human migrations have determined the spread of many infectious diseases by promoting the emergence of temporal outbreaks between populations. We aimed to analyze health indicators, expenditure, and disability caused by tuberculosis (TB) and HIV/AIDS burden under the Colombian-Venezuelan migration flow focusing on the Northeastern border. A retrospective study was conducted using TB and HIV/AIDS data since 2009. We consolidated a database using official reports from the Colombian Surveillance System, World Health Organization, Indexmundi, the Global Health Observatory, IHME HIV atlas, and Joint United Nations Programme on HIV/AIDS (UNAIDS). Disability metrics regarding DALYs (disability adjusted life years) and YLDs (years lived with disability), were compared between countries. Mapping was performed on ArcGIS using official migration data of Venezuelan citizens. Our results indicate that TB profiles from Colombia and Venezuela are identical in terms of disease burden, except for an increase in TB incidence in the Colombian-Venezuelan border departments in recent years, concomitantly with the massive Venezuelan immigration since 2005. We identified a four-fold underfunding for the TB program in Venezuela, which might explain the low-testing rates for cases of multidrug-resistant TB (67%) and HIV/AIDS (60%), as well as extended hospital stays (150 days). We found a significant increase in DALYs of HIV/AIDS patients in Venezuela, specifically, 362.35 compared to 265.37 observed in Colombia during 2017. This study suggests that the Venezuelan massive migration and program underfunding might exacerbate the dual burden of TB and HIV in Colombia, especially towards the Colombian‐Venezuelan border.

The effect of carbohydrates on the adherence of Pasteurella multocida to the nasal respiratory epithelium

Gallego López, Carolina | 2021

Pasteurella multocida subsp. multocida is responsible for different diseases that generate great economic losses in farm animal. The effectiveness of immunization against those bacteria are variable and the use of antibiotics is questioned; for that reason, we investigated the potential inhibitory effect of different carbohydrates on the adherence in vivo of P. multocida to the rabbit respiratory epithelium as an alternative for the prevention of respiratory infections. Rabbits were intranasally and intratracheally inoculated with a solution containing 200 µl of 1x107 CFU of P. multocida that was previously mixed with 250 µg /200 µl of N-acetylglucosamine, alphamethylglucoside, alphamethylmannoside, N-acetylgalactosamine or sialic acid. The animals that received N-acetylglucosamine, alphamethylglucoside or alphamethylmannoside individually or a mixture of these three carbohydrates plus the bacterium, showed a signifi cant decrease (P <0.05) of the clinical symptoms, microscopic and macroscopic lesions in the nasal septa and in the lungs; also, the number of adhered bacteria to the nasal epithelium were also signifi cantly reduced. This research demonstrates for the fi rst time that such an approach could convert into a method for prevention of P. multocida infection in rabbits that is ecologically and economically safe and effective

Una avifauna en cambio: 26 años de conteos navideños en la Sabana de Bogotá, Colombia

Stiles, F. Gary | 2021

El Conteo Navideño de aves en la Sabana de Bogotá se realiza anualmente desde 1989. Presentamos los resultados de los primeros 26 años (1989–2014) para detectar cambios en la presencia y las abundancias de las especies de aves e intentar relacionarlos con cambios en el clima, la vegetación, las interacciones entre especies y las actividades humanas. Los conteos corresponden a 29 localidades clasificadas en terrestres, mixtas o acuáticas según la composición de sus avifaunas. En cuatro sitios comparamos los patrones de recambio de especies entre años sucesivos. Calculamos para cada especie el número de años y número de sitios de registro, así como el promedio de individuos observados por año de registro. Analizamos los cambios de abundancia a lo largo de los 26 años de todas las especies registradas en seis o más años mediante regresiones lineales. Registramos 234 especies de aves: 126 residentes permanentes, 43 residentes estacionales (migratorias boreales invernantes) y 65 visitantes; las residentes fueron más abundantes y registradas por más años y sitios. Contamos más especies en los sitios terrestres con bosques nativos conservados; en los sitios acuáticos registramos más individuos debido a las especies gregarias. En los sitios con bosques conservados, las especies cambiaron poco en años sucesivos mientras las tasas de recambio fueron más altas en un parque urbano grande y un humedal. En este período, 49 especies aumentaron en abundancia, 30 disminuyeron y 74 no cambiaron; casi todos los cambios de abundancia ocurrieron entre las residentes. Seis especies se establecieron como residentes mientras cuatro aparentemente desaparecieron. En el intervalo estudiado, las influencias del cambio climático y las acciones directas o indirectas del hombre parecen haber afectado a más especies, especialmente por obras en los humedales y la urbanización; la contaminación aérea urbana aumentó el calentamiento, posiblemente facilitando el establecimiento de algunas especies de elevaciones menores. Información de los años 1960s indica que desde ese tiempo el drenaje de muchos humedales afectó más a la avifauna; el cambio climático tuvo una menor influencia. Hacia el futuro, seguramente se intensificará el calentamiento global, llevando a desaparecer algunas especies más de las montañas locales mientras más especies de zonas cálidas podrían establecerse en la parte plana. En conclusión, resulta relevante monitorear las aves a largo plazo usando los conteos navideños. Presentamos algunas recomendaciones para los que están considerando iniciar conteos, y sugerencias para análisis de los datos para los que ya están haciendo esfuerzos de monitoreo similares.

Purificación parcial de péptidos del veneno de escorpión Hadruroides charcasus (Karsch, 1879) con actividad antimicrobiana.

Pérez-Delgado, Orlando | 2021

Los venenos de muchas especies de escorpiones son fuentes ricas en componentes biológicamente activos, como los péptidos antimicrobianos, biomoléculas que aún no han sido estudiados del veneno de Hadruroides charcasus. El objetivo de este artículo es evaluar la actividad antimicrobiana de los péptidos parcialmente purificados del veneno del escorpión Hadruroides. asus. A partir de 15,46 mg de proteína total del veneno del escorpión H. charcasus se purificaron parcialmente sus péptidos por medio de cromatografía de filtración en gel empleando sephadex G-75, consecutivo a una cromatografía de intercambio iónico en CM-Sephadex C-25. El peso molecular estimado de los péptidos se determinó mediante electroforesis PAGE-SDS-Tris-Tricina al 15% y la evaluación de la actividad antibacteriana y antifúngica se empleó el método de microdilución y Kirby-Bauer con cepas de Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 29213, Pseudomonas aeruginosa ATCC 27853 y Candida albicans ATCC 10231. En la cromatografía de filtración en gel se obtuvieron 5 fracciones, de lo cual, la fracción IV presentó una concentración mínima inhibitoria de 3,6 mg/mL en S. aureus ATCC 29213 y en C. albicans ATCC 10231. De la cromatografía de intercambio se obtuvieron 7 fracciones, destacando la fracción OPDIV-5 con péptidos de 4 kDa; 5 kDa; 5,5 kDa y 6,4 kDa que presentó actividad antimicrobiana frente S. aureus ATCC 29213, E. coli ATCC 25922, P. aeruginosa ATCC 27853, C. albicans ATCC 10231.El veneno del escorpión H. charcasus presenta péptidos de naturaleza catiónica con actividad antibacteriana y antifúngica, según su actividad en las cepas evaluadas

The role of stem cells in uterine involution

Spooner, Madelyn | 2021

Uterine remodeling during pregnancy and repair postpartum are fundamental to the successful propagation of eutherian species. The most drastic remodeling occurs in species with invasively implanting embryos, including humans and mice. During embryo implantation, embryonic trophoblasts breach the epithelium, penetrating into the stroma. Stromal cell decidualization, which is critical for the establishment and maintenance of early pregnancy, occurs throughout the implantation site. Trophoblasts further invade into and remodel uterine spiral arteries, which is necessary for placental formation. The uterus increases in size up to 24-fold, which is largely attributed to myometrial expansion. Uterine changes that occur during pregnancy must then be resolved postpartum. Following parturition, the uterus repairs the remodeled tissue in the process of uterine involution. During involution, the majority of the endometrium is regenerated to replace the tissue that is shed postpartum. The myometrium returns to the pre-gravid state which is thought to occur through apoptosis and autophagy of smooth muscle cells. Although we understand the general process of postpartum uterine involution, the detailed mechanisms, particularly the role of putative stem cells, are poorly understood. This review discusses the evidence for the existence of epithelial, stromal and myometrial stem cells and their role in uterine involution. Gaps in knowledge and areas for future research are also considered. Studies of both postpartum and menstrual uterine repair, which likely involve similar mechanisms, are described under the broad definition of uterine involution. Although the primary focus of this review is human, mouse models are discussed to provide additional information.

Aislamiento de Morganella morganii y Staphylococcusaureus en un paciente canino con lesión cutánea y detejidos blandos: reporte de caso

Maldonado Vera, María Camila | 2021

Se presenta el caso clínico de un canino con pioderma profundo ulceroso connecrosis dérmica, donde se aísla Morganella morganii y Staphylococcus aureus delas lesiones cutáneas. El primero es una bacteria del medio ambiente y en la flora normaldel tracto intestinal, y poco reportada en caninos. S. aureus es una bacteria estafilocócicagrampositiva reconocida que se asocia con infecciones supurativas. Los resultadosque abordan este estudio indican la importancia de llevar a cabo un rápido reconoci-miento, diagnóstico e inicio de tratamiento basado en cultivos y antibiogramas. Lainfección polimicrobiana dificulta el tratamiento y su evolución, debiendo evitarse laprogresión de lesiones en piel y enfermedades sistémicas secundarias

Discovery of Alternative Chemotherapy Options for Leishmaniasis through Computational Studies of Asteraceae

Herrera-Acevedo, Chonny | 2021

Leishmaniasis is a complex disease caused by over 20 Leishmania species that primarily affects populations with poor socioeconomic conditions. Currently available drugs for treating leishmaniasis include amphotericin B, paromomycin, and pentavalent antimonials, which have been associated with several limitations, such as low efficacy, the development of drug resistance, and high toxicity. Natural products are an interesting source of new drug candidates. The Asteraceae family includes more than 23 000 species worldwide. Secondary metabolites that can be found in species from this family have been widely explored as potential new treatments for leishmaniasis. Recently, computational tools have become more popular in medicinal chemistry to establish experimental designs, identify new drugs, and compare the molecular structures and activities of novel compounds. Herein, we review various studies that have used computational tools to examine various compounds identified in the Asteraceae family in the search for potential drug candidates against Leishmania.

Bioassay-guided fractionation in Anacardium excelsum (bert. & balb. ex kunth) skeels (anacardiaceae)

Sequeda-Castañeda, Luis Gonzalo | 2021

Anacardium excelsum is a tree between 15 and 50 meters high, with a thick trunk and is present in some departments of Colombia. Its nut-shaped fruits were used in the old Upar Valley by natives (Valledupar) to make Caracolí bread. Most research has been done at the forest level, but there are few phytochemical and biological activity studies. This bioguided work shows the application of antioxidant methods (ABTS+•, DPPH• and DMPD+•) in the search for active compounds present in the fraction and subfractions of greater activity. The antioxidant capacity was measured to the crude extract in ethanol and the antioxidant activity of the fractions in petroleum ether, dichloromethane, and ethanol-butanol of testa, tegument, flower, fruit, seed, bark, and leaf. Column Chromatography, Thin Layer Chromatography and Gas Chromatography coupled to Mass Spectrometry were performed on the petroleum ether fraction of testa with greater antioxidant capacity, finding the following compounds: 3- pentadec(en)il-phenol, 3-pentadecyl-phenol, 3-heptadeca(dien)il-phenol, 3-heptadec(en)ilphenol, 3-heptadecyl-phenol, 3-nonadec(en)il-phenol, ethyl ester of hexadecanoic acid, ethyl ester of heptadecanoic acid , ethyl ester of linolenic acid, hexadecanoic acid butyl ester, ethyl ether of octadecanoic acid, ethyl ester of (Z)-9-octadecenoic acid, ethyl ester of 9,12- octadecadienoic acid and ethyl ester of eicosanoic acid. The results indicate that Anacardium excelsum is a potential source of bioactive compounds.

Manganese ferrite solid nanospheres solvothermally synthesized as catalyst for peroxymonosulfate activation to degrade and mineralize para-nitrophenol: Study of operational variables and catalyst reutilization

Mateus Montañez, Olga Lucia | 2021

MnFe2O4 solid nanospheres (MSN) were synthesized by a solvothermal method. The sample was then used as catalyst to activate potassium peroxymonosulfate (PMS) for the generation of sulfate (SO4.–) and hydroxyl (HO.) radicals to degrade and mineralize para-nitrophenol (PNP) in water. The aim of this work was to study the influence of operational variables on the activity of the MSN catalyst to degrade and mineralize PNP, the PMS consumption kinetics, the leaching of metal ions, and the removal of nitrogen. Results showed that 100% of PNP (0.1 mM) was removed in MSN/PMS system by degradation within 7 h at a dosage of 4 mM of PMS, 0.5 g L−1 of MSN, 40 °C, and pH0 5.8. The reusability of the MSN catalyst was also studied, and a PNP degradation pathway was proposed. The PNP degradation followed a pseudo-first-order kinetic model and the activation energy obtained was 37.1 kJ/mol. Under the above standard reaction conditions, the catalyst showed a good performance after five catalytic runs, with a degradation efficiency that exceeded 98%, and removed around 70% of total organic carbon in each run. The excellent reusability and long-term stability was verified by the characterization of fresh and used catalysts. The sole degradation products were maleic and fumaric acids and nitrate and nitrite ions.

In vivo pharmacokinetic evaluation of carprofen delivery from intra-articular nanoparticles in rabbits: A population modelling approach

Parra-Coca, A. | 2021

Osteoarthritis is treated with COX or fosfolipase A2 inhibitors such as carprofen, a propionic acid NSAID. The enhancement of its action over the articular cartilage is mandatory to facilitate its therapeutic application. Drug uptake into the cartilage requires high synovial fluid concentrations, anticipating its rapid distribution towards bloodstream. Thus, intraarticular administration improves local targeting of the drug, lining with the site of action. A pharmacokinetic study in rabbits has been performed to evaluate carprofen nanoparticles after intraarticular administration. Pharmacokinetic analysis of plasma profiles through a modelling approach, has demonstrated the rapid distribution of drug outside of synovial chamber but mainly remaining in plasma. The data modelling has demonstrated the existence of two release-absorption processes when the nanoparticles are administered in the synovial space. Additionally, results are predictive of the PK profile of some other species such as cat, dogs or humans

Cattle seroprevalence and risk factors associated with bovine viral diarrhea in the northeastern of Colombia

Martínez Rodriguez, Lorena Catalina | 2021

Bovine viral diarrhea (BVD) is one of the most common and economically significant viral infections in cattle. Different risk factors have been associated with viral exposure and transmission, generating endemic regions with different biotype circulations. To find the BVD status in the northeastern region of Colombia, this study aimed to determine the seroprevalence and risk factors associated with the disease in non-vaccinated farms. For this purpose, a two-time point sampling strategy was developed, obtaining serum from 1157 animals housed in 25 farms distributed in 46 townships, thus for antibody detection against nonstructural protein 3 (NS3, p80) of bovine viral diarrhea virus (BVDV) using an indirect ELISA test. For the first time in Colombia, the presence of serological persistent cattle was evaluated in 1047 animals 3 weeks later of first sampling. The information on a standardized questionnaire with closed and dichotomic answers was used to calculate the putative risk factors. The association analysis by univariate and multivariate logistic regression reported odds ratios (OR) with a 95% of confidence interval (C.I). The overall seroprevalence was 65% (95% CI 62.5–72.9%), with variations according to age ranges. The prevalence of persistent serological positive corresponded to 37.7% (95% CI 34.2–41.5). The risk factors found by multivariate analyses were the lease of pastures (OR = 2.071 CI 1.485–3.690), the use of the same needle (OR = 2.249 CI 1.354–3.736), the molasses supplementation (OR = 2.742 CI 1.156–5.807), and the native Creole breed (OR = 1.895 CI 1.416–2.804). The results of this study confirmed the endemism and higher common exposure to BVDV, as well as the presence of serological persistent cattle in Valledupar, Colombia.