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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. Structure-based insights from this study provide the basis for the selective targeting of CLIC4 to treat the associated pathologies.

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 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 by scent in human respiratory secretions (in vitro diagnosis), we retrained 5 of them to search and find the infection by scenting the patient directly (in vivo screening). 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. During in vivo efficacy experiments, our 5 dogs detected 92 COVID-19 positive patients among the 848 study subjects. The alert (lying down) was immediate, 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) in relation to rRT-PCR. Seventy-five days after finishing in vivo efficacy experiments, a real-life study (in vivo effectiveness) was executed among the riders of the Metro System of Medellin, deploying the human-canine teams without previous training or announcement. Three dogs were used to examine the scent of 550 volunteers who agreed to participate, both in test with canines and in 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 independent of key variables, such as disease prevalence, time post-exposure, or presence of symptoms. Additional training is required to teach the dogs to ignore odoriferous contamination under real-life conditions.

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.

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.

Efficient, easy to implement and low-cost monitoring methodologies are necessary to obtain information on arthropod pest populations and to implement the most convenient and timely phytosanitary control practices. To optimize the sampling and monitoring of the Asian citrus psyllid, Diaphorina citri (Hemiptera: Liviidae), an insect associated with the transmission of Candidatus Liberibacter asiaticus and Ca. L. americanus, which cause Huanglongbing (HLB), a disease with a great impact on citrus orchards, three methods of adult sampling (yellow sticky traps, sweep net, and stem tap) were evaluated. For immature sampling, vegetative shoots were checked. The results demonstrate that the population density at the time of sampling affects the effectiveness and sensitivity of the sampling methods. Yellow sticky traps capture more adults and are the only effective method at low psyllid densities. Stem tap and sweep net are less expensive methods; however, they do not detect adults nor correlate with the number of nymphs and eggs in vegetative shoots when adult density is low. For adults, an optimal sample size was determined for each method. For yellow sticky traps, 3 to 5 traps for a 2-hectare plot with weekly frequency are recommended. For immatures, it is recommended to estimate the percentage of infestation by inspecting 45 to 55 vegetative shoots well-distributed within a 2-hectare plot, as a practical measure for farmers and extensionists to monitor D. citri.

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.