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Supplementary data associated with this article can be found in the online version at doi:10.1016/j.csbj.2022.12.040., Acknowledgment We would like to thank the Center for High-Performance Computing, Cape Town, South Africa for providing computational resources and Dr Nabil Hajji for his kind contributions in enhancing the staining protocol., The use of computer-aided methods have continued to propel accelerated drug discovery across various disease models, interestingly allowing the specific inhibition of pathogenic targets. Chloride Intracellular Channel Protein 4 (CLIC4) is a novel class of intracellular ion channel highly implicated in tumor and vascular biology. It regulates cell proliferation, apoptosis and angiogenesis; and is involved in multiple pathologic signaling pathways. Absence of specific inhibitors however impedes its advancement to translational research. Here, we integrate structural bioinformatics and experimental research approaches for the discovery and validation of small-molecule inhibitors of CLIC4. High-affinity allosteric binders were identified from a library of 1615 Food and Drug Administration (FDA)-approved drugs via a high-performance computing-powered blind-docking approach, resulting in the selection of amphotericin B and rapamycin. NMR assays confirmed the binding and conformational disruptive effects of both drugs while they also reversed stress-induced membrane translocation of CLIC4 and inhibited endothelial cell migration. Structural and dynamics simulation studies further revealed that the inhibitory mechanisms of these compounds were hinged on the allosteric modulation of the catalytic glutathione (GSH)-like site loop and the extended catalytic β loop which may elicit interference with the catalytic activities of CLIC4. Structurebased insights from this study provide the basis for the selective targeting of CLIC4 to treat the associated pathologies.

The chloride intracellular channel (CLIC) protein family displays the unique feature of altering its structure from a soluble form to a membrane-bound chloride channel. CLIC1, a member of this family, is found in the cytoplasm or in internal and plasma membranes, with membrane relocalisation linked to endothelial disfunction, tumour proliferation and metastasis. The molecular switch promoting CLIC1 activation remains under investigation. Here, cellular Cl− efflux assays and immunofluorescence microscopy studies have identified intracellular Zn2+ release as the trigger for CLIC1 activation and membrane insertion. Biophysical assays confirmed specific binding to Zn2+, inducing membrane association and enhancing Cl− efflux in a pH-dependent manner. Together, our results identify a two-step mechanism with Zn2+ binding as the molecular switch promoting CLIC1 membrane insertion, followed by pH-mediated activation of Cl− efflux.

In the pineapple growing region of Lebrija, Santander, one of the largest such regions in Colombia, five farms were selected, and a sampling of symphylids associated with this crop was carried out in the first months of cultivation in the variety Perolera and hybrid MD2. Two collecting methods were compared: i) the destructive method, with soil inspection around the roots, and ii) the bait-trap method with pieces of potato mixed with soil. These two methods were implemented in the same plots during five bimonthly samplings. Additionally, the percentage of root damage was estimated, defined as the percentage of roots that show bifurcation due to the damage caused by symphylids. All symphylids were identified as Hanseniella sp. Sampling of symphylids based on underground potato bait traps requires fewer samples to estimate population density and is a predictor of root damage while destructive sampling is not. Consequently, trap sampling could be a useful tool for monitoring and managing symphylids on pineapple. The abundance was related to soil moisture, and not to soil pH.

Laparoscopic assisted cystotomy in a Paso Fino horse with a cystic calculus Urolithiasis is the presence of mineral concretions or urine crystals at the urinary tract. In horses, urolithiasis has a relatively low prevalence ( 0.4% to 0.5%), its presentation occurs at the level of the kidneys and the urinary bladder, the last one is the site of the greatest presentation. Most of the uroliths in horses are constituted for calcium carbonate. The diagnosis is commonly made by relating the findings of the clinical examination along with the ultrasound. Surgical resolution is the election for treatment. The patient was a 350 kg, twelve years old Colombian creole gelding referred with historical presentation of two months of pigmenturia and dysuria, to the transrectal palpation a round structure of approximately 7 cm of diameter was located in the urinary bladder, which was confirmed by ultrasound and cystoscopy, in addition, cytology of the urinary sediment was performed. The therapeutic approach was made with medical and surgical management by assisted laparoscopic approach. The aim of this case report is to describe for the first time a case of urolithiasis and its resolution by assisted laparoscopy in a Colombian Creole Horse. Cistotomia asistida por laparoscopia en un caballo de Paso Fino con calculo vesical La urolitiasis es la presencia de concreciones minerales de los cristales de orina en las vias urinarias. En los equinos esta patologia tiene una prevalencia baja (0,4% a 0,5%), su presentacion se da en rinones y vejiga generalmente, siendo esta ultima el sitio de mayor frecuencia. Los urolitos mas reportados en caballos se encuentran compuestos por carbonato de calcio. El diagnostico se realiza comunmente relacionando los hallazgos del examen clinico junto con la ecografia. Para el tratamiento se realiza abordaje quirurgico. Un equino macho castrado, criollo colombiano, de doce anos y un peso de 350 kg fue remitido para interconsulta por la presentacion historica de dos meses de pigmenturia y disuria, a la palpacion transrectal se encontro una estructura redonda y compacta de aproximadamente 7 cm de diametro ubicada en la vejiga, lo cual fue confirmado mediante ecografia vesical y cistoscopia, a su vez, se realizo citologia del sedimento urinario. El abordaje terapeutico se hizo mediante manejo medico y quirurgico por la tecnica de cistotomia asistida por laparoscopia. El objetivo de este articulo es describir el primer reporte de caso de un urolito y de una cistotomia asistida por laparoscopia en un Caballo Criollo Colombiano. Palabras clave: cistitis, cistotomia, equino, laparoscopia, urolito. Cistotomia assistida por laparoscopia em um cavalo de Paso Fino com calculo na bexiga A urolitiase e a presenca de concrecoes minerais macroscopicas de cristais de urina no trato urinario. A prevalencia desta afeccao em equinos e relativamente baixa (0,4% a 0,5%), geralmente acomete rins e vesicula urinaria, sendo esta ultima o principal local de apresentacao. A maior porcentagem dos urolitos de equinos e composta de carbonato de calcio. O diagnostico e comumente feito pela associacao dos achados do exame clinico e ultrassonograficos. A abordargem cirurgica e normalmente o tratamento de escolha, sendo realizada por meio de laparocistotomia. O paciente deste relato era um cavalo crioulo colombiano, com doze anos e pesando 350 kg, que foi encaminhado com historico de dois meses de pigmenturia e disuria. A palpacao transretal revelou uma estrutura esferica de cerca de 7 cm de diâmetro dentro bexiga, o foi confirmado por ultrassonografia e cistoscopia, seguido por citologia do sedimento urinario . A abordagem terapeutica foi realizada com manejo medico e cirurgico, que consistiu de tecnica de cistotomia assistida por videolaparoscopia. O objetivo deste relato de caso e descrever o primeiro caso de um urolito e uma cistotomia assistida por laparoscopia em um Cavalo Crioulo Colombiano. Palavras-chave: cistite, cistotomia, equino, laparoscopia, urolito.

Timely and accurate diagnostics are essential to fight the COVID-19 pandemic, but no test satisfies both conditions. Dogs can scent-identify the unique odors of the volatile organic compounds generated during infection by interrogating specimens or, ideally, the body of a patient. After training 6 dogs to detect SARS-CoV-2 in human respiratory secretions (in vitro scent-detection), we retrained 5 of them to diagnose the infection by scenting the patient directly (in vivo scent-detection). Then, efficacy trials were designed to compare the diagnostic performance of the dogs against that of the rRT-PCR in 848 human subjects: 269 hospitalized patients (COVID-19 prevalence 30.1%), 259 hospital staff (prevalence 2.7%), and 320 government employees (prevalence 1.25%). The limit of detection in vitro was lower than 10-12 copies ssRNA/mL. In vivo, all dogs detected 92 COVID-19 patients present among the 848 study subjects. Detection was immediate, and independent of prevalence, time post-exposure, or presence of symptoms, with 95.2% accuracy and high sensitivity (95.9%; 95% C.I. 93.6-97.4), specificity (95.1%; 94.4-95.8), positive predictive value (69.7%; 65.9-73.2), and negative predictive value (99.5%; 99.2-99.7). To determine real-life performance, we waited 75 days to carry out an effectiveness assay among the riders of the Metro System of Medellin, deploying the human-canine teams without previous training or announcement. Three dogs (one of each breed) scent-interrogated 550 citizens who volunteered for simultaneous canine and rRT-PCR testing. Negative predictive value remained at 99.0% (95% C.I. 98.3-99.4), but positive predictive value dropped to 28.2% (95% C.I. 21.1-36.7). Canine scent-detection in vivo is a highly accurate screening test for COVID-19, and it detects more than 99% of infected individuals independently of the key variables. However, real-life conditions increased substantially the number of false positives, indicating the necessity of training a threshold for the limit of detection to discriminate environmental odoriferous contamination from infection.

Human dendritic cell-specific intercellular adhesion molecule-1 grabbing nonintegrin, DC-SIGN, and the sinusoidal endothelial cell receptor DC-SIGNR or L-SIGN, are closely related sugar-binding receptors. DC-SIGN acts both as a pathogen-binding endocytic receptor and as a cell adhesion molecule, while DC-SIGNR has only the pathogen-binding function. In addition to differences in the sugar-binding properties of the carbohydrate-recognition domains in the two receptors, there are sequence differences in the adjacent neck domains, which are coiled-coil tetramerization domains comprised largely of 23-amino acid repeat units. A series of model polypeptides consisting of uniform repeat units have been characterized by gel filtration, differential scanning calorimetry and circular dichroism. The results demonstrate that two features characterize repeat units which form more stable tetramers: a leucine reside in the first position of the heptad pattern of hydrophobic residues that pack on the inside of the coiled coil and an arginine residue on the surface of the coiled coil that forms a salt bridge with a glutamic acid residue in the same polypeptide chain. In DC-SIGNR from all primates, very stable repeat units predominate, so the carbohydrate-recognition domains must be held relatively closely together. In contrast, stable repeat units are found only near the membrane in DC-SIGN. The presence of residues that disrupt tetramer formation in repeat units near the carbohydrate-recognition domains of DC-SIGN would allow these domains to splay further apart. Thus, the neck domains of DC-SIGN and DC-SIGNR can contribute to the different functions of these receptors by presenting the sugar-binding sites in different contexts. This article is protected by copyright. All rights reserved.

Se reporta el caso de una yegua criolla colombiana de 18 años con historia de subfertilidad: celos continuos y prolongados, edema uterino categorizado entre 4 y 5, y quistes de tamaño moderado presentes en la capa endometrial y miometrial. Como plan diagnóstico se realizó un cultivo endometrial, histeroscopía y biopsia para histopatología. En el aislamiento del cultivo se encontró Proteus mirabilis. La histeroscopía mostró abundantes quistes en el cuerpo y cuernos uterinos. En la histopatología se evidenció hiperplasia de las glándulas endometriales con focos fibróticos e infiltrado mononuclear. La terapia con antibióticos, dimetil sulfóxido DMSO e infusión de plasma rico en plaquetas no mejoró su condición y la yegua no recuperó su función reproductiva.

The Sigma-1 Receptor (S1R) is a small, ligand-regulated integral membrane protein involved in cell homeostasis and the cellular stress response. The receptor has a multitude of protein and small molecule interaction partners with therapeutic potential. Newly reported structures of the human S1R in ligand-bound states provides essential insights into small molecule binding in the context of the overall protein structure. The structure also raises many interesting questions and provides an excellent starting point for understanding the molecular tricks employed by this small membrane receptor to modulate a large number of signaling events. Here, we review insights from the structures of ligand-bound S1R in the context of previous biochemical studies and propose, from a structural viewpoint, a set of important future directions.

Background: Sigma-1 receptor is a ligand-regulated membrane protein chaperone involved in BiP regulation and the ER stress response. Results: The chaperone domain of human sigma-1 receptor is mostly helical with short extended regions. Conclusion: Regions of the sigma-1 receptor chaperone domain implicated in ligand and cholesterol binding can be mapped to separate helices. Significance: A structural framework for delineating sigma-1 receptor BiP and ligand interactions is presented., The sigma-1 receptor (S1R) is a ligand-regulated membrane protein chaperone involved in the ER stress response. S1R activity is implicated in diseases of the central nervous system including amnesia, schizophrenia, depression, Alzheimer disease, and addiction. S1R has been shown previously to regulate the Hsp70 binding immunoglobulin protein (BiP) and the inositol triphosphate receptor calcium channel through a C-terminal domain. We have developed methods for bacterial expression and reconstitution of the chaperone domain of human S1R into detergent micelles that enable its study by solution NMR spectroscopy. The chaperone domain is found to contain a helix at the N terminus followed by a largely dynamic region and a structured, helical C-terminal region that encompasses a membrane associated domain containing four helices. The helical region at residues ∼198–206 is strongly amphipathic and proposed to anchor the chaperone domain to micelles and membranes. Three of the helices in the C-terminal region closely correspond to previously identified cholesterol and drug recognition sites. In addition, it is shown that the chaperone domain interacts with full-length BiP or the isolated nucleotide binding domain of BiP, but not the substrate binding domain, suggesting that the nucleotide binding domain is sufficient for S1R interactions.

Highlights • The second transmembrane domain (TM2) of S1R includes residues 91–107. • The S1R cytosolic region contains three α-helices. • The chaperone domain structure is largely unperturbed by the addition of TM2., The sigma-1 receptor (S1R) is a ligand-regulated membrane chaperone protein associated with endoplasmic reticulum stress response, and modulation of ion channel activities at the plasma membrane. We report here a solution NMR study of a S1R construct (S1R(Δ35)) in which only the first transmembrane domain and the eight-residue N-terminus have been removed. The second transmembrane helix is found to be composed of residues 91–107, which corresponds to the first steroid binding domain-like region. The cytosolic domain is found to contain three helices, and the secondary structure and backbone dynamics of the chaperone domain are consistent with that determined previously for the chaperone domain alone. The position of TM2 provides a framework for ongoing studies of S1R ligand binding and oligomerisation.

El Berenjenol (21:24-epoxi-24-metil-cicloartano), obtenido del extracto de diclorometano de las hojas de Oxandra cf. xylopioides, es evaluado como biocida sobre el gusano cogollero del maíz, Spodoptera frugiperda. El berenjenol es usado en concentraciones de 25, 50, 100, 200 y 400 ppm y aplicado en una dieta artificial sobre larvas del segundo instar. Se determina el porcentaje de mortalidad a las 24, 48 y 72 horas y se calcula la DL50 y DL90; el análisis de mortalidad demuestra que el berenjenol tiene un efecto tóxico, siendo la dosis de 400 ppm la más mortal. El efecto del berenjenol es muy rápido y efectivo encontrándose valores de DL50 de 319.6 ppm a las 24 horas y valores similares a las 48 y 72 horas. Berenjenol (21:24-epoxy-24-methyl-cycloartane) extracted from the leaves of Oxandra cf. Xylopioides, is evaluated as a biocide on Spodoptera frugiperda. Berenjenol is used at 25, 50, 100, 200 and 400 ppm, and is applied in an artificial diet of larvae in the second instar. The mortality percentage is determined at 24, 48 and 72 hours and LD50 and DL90 are calculated; the mortality analysis shows that berenjenol has a toxic effect, being the most mortal dose at 400 ppm. The effect of berenjenol is fast and effective, finding DL50 at 319.6 ppm after 24 h and similar values at 48 and 72 hours.