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We propose a compact, portable, and low-cost holographic microscope designed for the characterization of micrometric particles suspended in a liquid. This system is built around a commercial optical microscope by substituting its illumination source (a light-emitting diode) with a collimated laser beam. Similarly, a quartz flow cell replaces the microscope glass slide using a 3D-printed custom mount. With the hardware presented in this paper, the holographic imaging of the electromagnetic fields emitted by the particles that intercept the laser beam achieves a resolution close to that of optical microscopes but with a greater depth of field. Several morphological and optical features can be extracted from the holograms, including particle projected section, aspect ratio, and extinction cross-section. Additionally, we introduce a remote system control that enables users to process the acquired holograms on a remote computational device. This work provides a comprehensive description of the methodology of image processing in holographic microscopy and a series of validation measurements conducted using calibrated particles. This technique is suitable for the characterization of airborne particles found in snow, firn, and ice; here we report experimental results obtained from Alpine ice cores.

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PURPOSE: To compare texture-based analysis using convolutional neural networks (CNNs) against lung densitometry in detecting chest computed tomography (CT) image abnormalities. MATERIAL AND METHODS: A U-NET was used for lung segmentation, and an ensemble of 7 CNN architectures was trained for the classification of low-attenuation areas (LAAs; emphysema, cysts), normal-attenuation areas (NAAs; normal parenchyma), and high-attenuation areas (HAAs; ground-glass opacities, crazy paving/linear opacity, consolidation). Lung densitometry also computes (LAAs, ≤-950 HU), NAAs (-949 to -700 HU), and HAAs (-699 to -250 HU). CNN-based and densitometry-based severity indices (CNN and Dens, respectively) were calculated as (LAA+HAA)/(LAA+NAA+HAA) in 812 CT scans from 176 normal subjects, 343 patients with emphysema, and 293 patients with interstitial lung disease (ILD). The correlation between CNN-derived and densitometry-derived indices was analyzed, alongside a comparison of severity indices among patient subgroups with emphysema and ILD, using the Spearman correlation and ANOVA with Bonferroni correction. RESULTS: CNN-derived and densitometry-derived severity indices (SIs) showed a strong correlation (ρ=0.90) and increased with disease severity. CNN-SIs differed from densitometry SIs, being lower for emphysema and higher for moderate to severe ILD cases. CNN estimations for normal attenuation areas were higher than those from densitometry across all groups, indicating a potential for more accurate characterization of lung abnormalities. CONCLUSIONS: CNN outputs align closely with densitometry in assessing lung abnormalities on CT scans, offering improved estimates of normal areas and better distinguishing similar abnormalities. However, this requires higher computing power.

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Phthalic acid esters (PAE) are widely used as plasticizers and have been classified as ubiquitous environmental contaminants of primary concern. PAE have accumulated intensively in surface water, groundwater, and wastewaters; thus, PAE degradation is essential. In the present study, the ability of a saline soil bacteria (SSB)-consortium to degrade synthetic wastewater-phthalates with alkyl chains of different lengths, such as diethyl phthalate (DEP), di-n-butyl phthalate (DBP), benzyl butyl phthalate (BBP), and di (2-ethylhexyl) phthalate (DEHP) was characterized. A central composite design-response surface methodology was applied to optimize the degradation of each phthalate, where the independent variables were temperature (21-41 °C), pH (5.3-8.6) and PAE concentration (79.5-920.4 mg L-1), and Gas Chromatography-Mass Spectrometry was used to identify the metabolites generated during phthalate degradation. Optimal conditions were 31 °C, pH 7.0, and an initial PAE concentration of 500 mg L-1, where the SSB-consortium removed 84.9%, 98.47%, 99.09% and 98.25% of initial DEP, DBP, BBP, and DEHP, respectively, in 168h. A first-order kinetic model explained - the biodegradation progression, while the half-life of PAE degradation ranged from 12.8 to 29.8 h. Genera distribution of the SSB-consortium was determined by bacterial meta-taxonomic analysis. Serratia, Methylobacillus, Acrhomobacter, and Pseudomonas were the predominant genera; however, the type of phthalate directly affected their distribution. Scanning electron microscopy analysis showed that high concentrations (1000 mg L-1) of phthalates induced morphological alterations in the bacterial SSB-consortium. The metabolite profiling showed that DEP, DBP, BBP, and DEHP could be fully metabolized through the de-esterification and ß-oxidation pathways. Therefore, the SSB-consortium can be considered a potential candidate for bioremediation of complex phthalate-contaminated water resources.

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This study aimed to compare the effects of two extraction techniques (conventional n-hexane and supercritical CO2) on the oil extraction yields, fatty acids profile, anti-hyaluronidase activity, oxidative stability, and in vitro bioactivities of oils from Sacha Inchi (Plukenetia volubilis). Higher oil extraction yield (99 %) was achieved using the SC-CO2, although similar fatty acids profiles were depicted between both treatments (p < 0.05). The SC-CO2 oil presented higher anti-hyaluronidase (31 %) activity, but lower oxidative stability (5.05 h) compared to the solvent extraction (10 %, and 5.3 h, respectively). In vitro assays further revealed that the best human normal colon cells (FHC) cell viability (100 %), anti-inflammatory (50 % lower NO production), and antioxidant (20 % ROS reduction) activities were consistently observed in both extraction treatments at concentrations of 50 µg/mL and higher. These findings highlight the potential of supercritical CO2 extraction in yielding Sacha Inchi oil with enhanced bioactive properties without the disadvantages of the use of organic solvents extraction.

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The HIV-1 envelope glycoprotein (Env) is expressed at the surface of infected cells and as such can be targeted by non-neutralizing antibodies (nnAbs) that mediate antibody-dependent cellular cytotoxicity (ADCC). Previous single-molecule Förster resonance energy transfer (smFRET) studies demonstrated that Env from clinical isolates predominantly adopt a "closed" conformation (State 1), which is resistant to nnAbs. After interacting with the cellular receptor CD4, the conformational equilibrium of Env shifts toward States 2 and 3, exposing the coreceptor binding site (CoRBS) and permitting binding of antibodies targeting this site. We showed that the binding of anti-CoRBS Abs enables the engagement of other nnAbs that target the cluster A epitopes on Env. Anti-cluster A nnAbs stabilize an asymmetric Env conformation, State 2A, and have potent ADCC activity. CRF01_AE strains were suggested to be intrinsically susceptible to ADCC mediated by nnAbs. This may be due to the presence of a histidine at position 375, known to shift Env towards more "open" conformations. In this work, through adaptation of an established smFRET imaging approach, we report that the conformational dynamics of native, unliganded HIV-1CRF01_AE Env indicates frequent sampling of the State 2A conformation. This is in striking contrast with Envs from clades A and B, for example HIV-1JR-FL, which do not transition to State 2A in the absence of ligands. These findings inform on the conformational dynamics of HIV-1CRF01_AE Env, which are relevant for structure-based design of both synthetic inhibitors of receptor binding, and enhancers of ADCC as therapeutic alternatives.

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We develop a multiscale coarse-grain model of the NIST Monoclonal Antibody Reference Material 8671 (NISTmAb) to enable systematic computational investigations of high-concentration physical instabilities such as phase separation, clustering, and aggregation. Our multiscale coarse-graining strategy captures atomic-resolution interactions with a computational approach that is orders of magnitude more efficient than atomistic models, assuming the biomolecule can be decomposed into one or more rigid bodies with known, fixed structures. This method reduces interactions between tens of thousands of atoms to a single anisotropic interaction site. The anisotropic interaction between unique pairs of rigid bodies is precomputed over a discrete set of relative orientations and stored, allowing interactions between arbitrarily oriented rigid bodies to be interpolated from the precomputed table during coarse-grained Monte Carlo simulations. We present this approach for lysozyme and lactoferrin as a single rigid body and for the NISTmAb as three rigid bodies bound by a flexible hinge with an implicit solvent model. This coarse-graining strategy predicts experimentally measured radius of gyration and second osmotic virial coefficient data, enabling routine Monte Carlo simulation of medically relevant concentrations of interacting proteins while retaining atomistic detail. All methodologies used in this work are available in the open-source software Free Energy and Advanced Sampling Simulation Toolkit.

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The relationship between diet and behavior is essential to understanding an animal's strategies to obtain food, considering ontogenical changes. In reptiles, there is a relationship between the length of the individual and the size of the prey it consumes. Studies have focused on the ontogenetic changes in reptile diets from hatchling to adult, but only a few studies have focused on the transition from hatchling to juvenile. We aimed to describe and analyze the composition, variation, diversity, and overlap in the diet of hatchling Morelet's crocodiles (Crocodylus moreletii) for three size intervals during the hatchling-juvenile transition. We captured 31 hatchling Morelet's crocodiles in an urbanized lagoon in Tabasco. We performed stomach-flushing to determine the diet. Additionally, we estimated the volume, frequency of occurrence, and relative importance of diet items and analyzed the relationship between prey type and the total length of the individuals. The diversity of the hatchling prey suggests a generalist diet. We observed two items not previously described in the diet of hatchling crocodiles. In addition, we found differences in diet between the initial and final size intervals, as increases in the length of prey appeared that they did not consume when they were hatchlings. Our results contribute new information to the dietary changes that occur during the hatchling-juvenile transition.

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The success of using active restoration in Mediterranean-type climate zones mostly depends on an appropriate matching of plant species and specific management prescriptions upon establishment. In this study, we assessed the early growth and short-term physiological acclimation of seven common species found in the sclerophyllous forests in central Chile to water restriction and shading. We established a nursery experiment that included three treatments (T0: sun-exposed and water-restricted, T1: sun-exposed and fully irrigated, and T2: shaded and fully irrigated) and seven tree species differing in their shade and drought tolerance (Quillaja saponaria Molina, Aristotelia chilensis (Mol.) Stuntz, Peumus boldus Molina, Lithraea caustica (Mol.) Hook. and Arn, Luma apiculata (DC.) Burret, Colliguaja odorifera Molina, and Escallonia pulverulenta (Ruiz and Prav.) Pers). We measured the increment in seedling height and different leaf morpho-physiological traits during two months in the dry season. Based on the measured traits, none of the species took advantage of the higher water availability in T1 relative to T0, but most of the species responded to the shade in T2, regardless of their shade or drought tolerance. Height increments due to shade varied from 0% in P. boldus to 203% in L. apiculata. Overall, all the species responded similarly to the treatments in specific leaf area, chlorophyll content index, photosynthetic rate, stomatal conductance, and intrinsic water use efficiency. This suggests that the species exhibited similar acclimation patterns of these parameters to shade and drought, even regarding the variation in midday xylem water potential found in the water-restricted treatment T0 (from -1.5 MPa in P. boldus to -3.1 MPa in E. pulverulenta). In this study, shading had a higher positive effect on the seedling performance of sclerophyllous species than watering, which at operational level highlights the need for investing in tree shelters when using these species in restoration programs.

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BACKGROUND: Common variable immunodeficiency (CVID) is a heterogeneous disorder characterized by defective antibody production and impaired differentiation of B cells. B cell proliferation is an essential step for antibody synthesis. Depending on the nature of the stimulus, their response may be either T-cell-dependent or T-cell-independent. METHODS: We studied 23 CVID patients and 14 healthy donors (HD). The patients were categorized based on their percentage of memory B cells. In addition to standard immunophenotyping of circulating human B and T cell subsets, an in vitro CFSE dilution assay was used to assess the proliferative capacity of B cells and to compare the activation of the T cell-dependent and T cell-independent response among the patients. RESULTS: Patients with a reduction in memory B cells exhibited an increase in follicular T cells (Tfh) and showed low proliferation in response to PKW, CpG, and SAC stimuli (Condition II) (p= 0.0073). In contrast, patients with a normal percentage of memory B cells showed a high expression of IL-21R and low proliferation in response to CPG (Condition III); IL-21, CD40L, and anti-IgM (Condition IV) stimuli (p= 0.0163 and p = 0.0475, respectively). CONCLUSION: Defective proliferation in patients depends on the type of stimulus used and the phenotypic characteristics of the patients. Further studies are necessary to understand the disease mechanisms, which may guide us toward identifying genetic defects associated with CVID.

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The majority of naturally elicited antibodies against the HIV-1 envelope glycoproteins (Env) are non-neutralizing (nnAbs) because they are unable to recognize the Env trimer in its native "closed" conformation. Nevertheless, it has been shown that nnAbs have the potential to eliminate HIV-1-infected cells by antibody-dependent cellular cytotoxicity (ADCC) provided that Env is present on the cell surface in its "open" conformation. This is because most nnAbs recognize epitopes that become accessible only after Env interaction with CD4 and the exposure of epitopes that are normally occluded in the closed trimer. HIV-1 limits this vulnerability by downregulating CD4 from the surface of infected cells, thus preventing a premature encounter of Env with CD4. Small CD4-mimetics (CD4mc) sensitize HIV-1-infected cells to ADCC by opening the Env glycoprotein and exposing CD4-induced (CD4i) epitopes. There are two families of CD4i nnAbs, termed anti-cluster A and anti-CoRBS Abs, which are known to mediate ADCC in the presence of CD4mc. Here, we performed Fab competition experiments and found that anti-gp41 cluster I antibodies comprise a major fraction of the plasma ADCC activity in people living with HIV (PLWH). Moreover, addition of gp41 cluster I antibodies to cluster A and CoRBS antibodies greatly enhanced ADCC-mediated cell killing in the presence of a potent indoline CD4mc, CJF-III-288. This cocktail outperformed broadly neutralizing antibodies and even showed activity against HIV-1-infected monocyte-derived macrophages. Thus, combining CD4i antibodies with different specificities achieves maximal ADCC activity, which may be of utility in HIV cure strategies.IMPORTANCEThe elimination of HIV-1-infected cells remains an important medical goal. Although current antiretroviral therapy decreases viral loads below detection levels, it does not eliminate latently infected cells that form the viral reservoir. Here, we developed a cocktail of non-neutralizing antibodies targeting highly conserved Env regions and combined it with a potent indoline CD4mc. This combination exhibited potent ADCC activity against HIV-1-infected primary CD4 + T cells as well as monocyte-derived macrophages, suggesting its potential utility in decreasing the size of the viral reservoir.

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PURPOSE: To report on our experience using intravitreal methotrexate (MTX) in patients with retinal detachment associated with proliferative vitreoretinopathy and/or open globe injury. METHODS: This study performed a retrospective chart review of a consecutive series of 21 eyes of 21 patients who underwent serial intravitreal MTX injection for treatment and/or prevention of proliferative vitreoretinopathy from December 2021 to January 2024. RESULTS: Twenty-one patients underwent pars plana vitrectomy, membrane peeling, laser photocoagulation, silicone oil infusion, and intravitreal MTX injection. Postoperatively, all eyes received a series of intravitreal MTX (400 µg/0.1 mL) injections. Optimally, injections were administered weekly for 8 weeks and every 2 weeks for four weeks for a total of 13 injections, beginning intraoperatively at the conclusion of retinal reattachment surgery. Mean baseline preoperative and postoperative visual acuity was logarithm of the minimum angle of resolution 3.2 (approximately hand motions vision) and 2.5 (between CF and hand motions vision), respectively, yielding an average improvement in visual acuity of 0.7 logarithm of the minimum angle of resolution units (0 ETDRS lines/letters). These 21 patients received an average of 10.5 injections. With a single operation, detachments in 19 (90%) of 21 eyes were successfully reattached. Corneal epithelial defects were noted in 7 (33%) of 21 patients. CONCLUSION: Serial intravitreal MTX injection was associated with 90% single operation retinal reattachment rate in the setting of retinal detachment with proliferative vitreoretinopathy or retinal detachment at high risk of proliferative vitreoretinopathy.

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HIV-1 envelope glycoproteins (Env) from primary HIV-1 isolates typically adopt a pretriggered "closed" conformation that resists to CD4-induced (CD4i) non-neutralizing antibodies (nnAbs) mediating antibody-dependent cellular cytotoxicity (ADCC). CD4-mimetic compounds (CD4mcs) "open-up" Env allowing binding of CD4i nnAbs, thereby sensitizing HIV-1-infected cells to ADCC. Two families of CD4i nnAbs, the anti-cluster A and anti-coreceptor binding site (CoRBS) Abs, are required to mediate ADCC in combination with the indane CD4mc BNM-III-170. Recently, new indoline CD4mcs with improved potency and breadth have been described. Here, we show that the lead indoline CD4mc, CJF-III-288, sensitizes HIV-1-infected cells to ADCC mediated by anti-CoRBS Abs alone, contributing to improved ADCC activity. Structural and conformational analyses reveal that CJF-III-288, in combination with anti-CoRBS Abs, potently stabilizes an asymmetric "open" State-3 Env conformation, This Env conformation orients the anti-CoRBS Ab to improve ADCC activity and therapeutic potential.

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BACKGROUND: Genome DNA methylation profiling is a promising yet costly method for cancer classification, involving substantial data. We developed an ensemble learning model to identify cancer types using methylation profiles from a limited number of CpG sites. METHODS: Analyzing methylation data from 890 samples across 10 cancer types from the TCGA database, we utilized ANOVA and Gain Ratio to select the most significant CpG sites, then employed Gradient Boosting to reduce these to just 100 sites. RESULTS: This approach maintained high accuracy across multiple machine learning models, with classification accuracy rates between 87.7% and 93.5% for methods including Extreme Gradient Boosting, CatBoost, and Random Forest. This method effectively minimizes the number of features needed without losing performance, helping to classify primary organs and uncover subgroups within specific cancers like breast and lung. CONCLUSIONS: Using a gradient boosting feature selector shows potential for streamlining methylation-based cancer classification.

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Cellular communication is regulated at the plasma membrane by the interactions of receptor, adhesion, signaling, and endocytic proteins. Yet, the composition and control of these complexes in response to external cues remain unclear. We use high-resolution and high-throughput fluorescence imaging to map the localization of growth factor receptors and related proteins at single clathrin-coated structures in human squamous HSC3 cells. We find distinct protein signatures between control cells and cells stimulated with growth factors. Clathrin sites at the plasma membrane are preloaded with some receptors but not others. Stimulation with epidermal growth factor induces capture and concentration of epidermal growth factor-, fibroblast growth factor-, and low-density lipoprotein-receptors (EGFR, FGFR1, and LDLR). Regulatory proteins including ubiquitin ligase Cbl, the scaffold Grb2, and the mechanoenzyme dynamin2 are also recruited. Disrupting FGFR or EGFR activity with drugs prevents the recruitment of both EGFR and FGFR1. EGF was able to activate FGFR1 phosphorylation. Our data reveals novel co-clustering and activation of receptors and regulatory factors at clathrin-coated sites in response to stimulation by a single growth factor, EGF or FGF. This behavior integrates growth factor signaling and allows for complex responses to extracellular cues and drugs at the plasma membrane of human cells.

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INTRODUCTION: Frailty is a recognized condition associated with poorer outcomes in patients with head and neck cancer (HNC). The objective of this study was to ascertain the prognostic significance of various frailty metrics on short-term treatment toxicity in patients with HNC undergoing curative-intent therapy. MATERIALS AND METHODS: A systematic review was performed searching multiple databases. An inverse-variation, random-effects model was used to perform the meta-analysis to evaluate the prognostic significance of various frailty metrics on short-term treatment-related toxicity in this population. RESULTS: A total of 292,560 patients with HNC originating from 36 observational studies were analyzed. The most frequently reported frailty metrics were the modified frailty index (mFI), Geriatric 8 questionnaire (G8), Adjusted Clinical Groups (ACG), Groningen Frailty Indicator (GFI), and comprehensive geriatric assessment (CGA). The overall prevalence of frailty using any metric in all included studies was 7.5 %. The combined odds ratio (OR) for short-term treatment toxicity using the mFI was 2.60 (95 % CI of 1.81-3.72), G8 2.69 (95 % CI 1.37-5.28), ACG 3.43 (95 %CI 2.52-4.67), GFI 2.71 (95 % CI 1.11-6.62), and CGA 3.36 (95 % CI 1.18-9.53). The association of frailty with short-term treatment toxicity using various frailty metrics was more pronounced in patients with upfront surgery (OR 3.00, 95 %CI of 2.35-3.81) compared to definitive (chemo)radiotherapy 2.64 (95 % CI 1.04-6.68). DISCUSSION: Various frailty metrics exists in the HNC literature, with the most common being the mFI, G8, ACG, GFI, and CGA. Patients with HNC and frailty are more than twice as likely to suffer a short-term treatment-related toxicity when undergoing curative-intent HNC treatment than patients without frailty. This effect is more pronounced in patients undergoing upfront surgery.

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Transcriptomic profiles are important indicators for molecular mechanisms and pathways involved in major depressive disorder (MDD) and its different phenotypes, such as immunometabolic depression. We performed whole-transcriptome and pathway analyses on 139 individuals from the observational, case-control, BIOmarkers in DEPression (BIODEP) study, 105 with MDD and 34 controls. We divided MDD participants based on levels of inflammation, as measured by serum high-sensitivity C-reactive protein (CRP), in n = 39 'not inflamed' (CRP < 1 mg/L), n = 31 with 'elevated CRP' (1-3 mg/L), and n = 35 with 'low-grade inflammation' (>3 mg/L). We performed whole-blood RNA sequencing using Illumina NextSeq 550 and statistical analyses with the Deseq2 package for R statistics (RUV-corrected) and subsequent pathway analyses with Ingenuity Pathway Analysis. Immunometabolic pathways were activated in individuals with CRP > 1 mg/L, although surprisingly the CRP 1-3 group showed stronger immune activation than the CRP > 3 group. The main pathways identified in the comparison between CRP < 1 group and controls were cell-cycle-related, which may be protective against immunometabolic abnormalities in this 'non-inflamed' depressed group. We further divided MDD participants based on exposure and response to antidepressants (n = 47 non-responders, n = 37 responders, and n = 22 unmedicated), and identified specific immunomodulatory and neuroprotective pathways in responders (especially vs. non-responders), which could be relevant to treatment response. In further subgroup analyses, we found that the specific transcriptional profile of responders is independent of CRP levels, and that the inhibition of cell-cycle-related pathways in MDD with CRP < 1 mg/L is present only in those who are currently depressed, and not in the responders. The present study demonstrates immunometabolic and cell-cycle-related transcriptomic pathways associated with MDD and different (CRP-based and treatment-based) MDD phenotypes, while shedding light on potential molecular mechanisms that could prevent or facilitate an individual's trajectory toward immunometabolic depression and/or treatment-non-responsive depression. The recognition and integration of these mechanisms will facilitate a precision-medicine approach in MDD.

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PURPOSE: We assessed the potential association between N-acetyl-cysteine (NAC) and clinical outcomes in critically ill subjects with COVID-19-related ARDS. MATERIAL AND METHODS: We included subjects with confirmed COVID-19 who were admitted to our ICU between March 1, 2020, and January 31, 2021, due to ARDS and necessitating invasive mechanical ventilation (IMV). Subjects who received standard of care (SOC) were compared with subjects who additionally received NAC 600 mg bid orally. RESULTS: A total of 243 subjects were included in this study. The results indicate significantly improved survival rates in the NAC plus SOC group, both in the unadjusted analysis and after adjusting for confounding factors such as ARDS severity (HR 0.48, 95% CI 0.32-0.70). CONCLUSIONS: We found that oral administration of NAC was associated with reduced mortality in critically ill patients with COVID-19 related ARDS.

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Background: Over the past decade, 3D printing technology has revolutionized various fields, including dentistry. Provisional restorations play a crucial role in prosthetic rehabilitation, necessitating the evaluation of their bond strength with different provisional cement agents. Aims: This study is aimed at assessing the immediate and long-term bond strength of 3D-printed dental crowns using three provisional cement agents. Materials and Methods: Provisional crowns (N = 36) were manufactured using 3D modeling software and cemented in dentin analogues (G10 Nema resin). After the crowns' fabrication, they were randomly divided into three groups (n = 12) for cementation with Relyx Temp 3M ESPE, Provicol-VOCO, and Meron-VOCO. Tensile strength tests were conducted using a universal testing machine, with half of the specimens subjected to 2000 thermal cycles before testing. Finite element analysis was employed to assess tensile stress distribution. Results: Statistical analysis (two-way ANOVA and Tukey's test at a 95% confidence level) revealed significant effects of cement type (p = 0.006) and thermal aging (p = 0.001) on bond strength. Glass ionomer cement exhibited the highest immediate resistance, while all types of cement were adversely affected by thermal aging, resulting in decreased bond strength. Conclusion: Thermal aging significantly alters the properties of 3D printing resin and affects the bond strength of provisional cement with 3D-printed crowns. Despite the adverse effects of thermal aging, glass ionomer cement demonstrated the highest immediate resistance. Clinicians should carefully consider these findings when selecting provisional cements for 3D-printed crowns.

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The effect of peptide toxins on voltage-gated ion channels can be reliably assessed using electrophysiological assays, such as the patch-clamp technique. However, much of the toxinological research done in Central and South America aims at purifying and characterizing biochemical properties of the toxins of vegetal or animal origin, lacking electrophysiological approaches. This may happen due to technical and infrastructure limitations or because researchers are unfamiliar with the techniques and cellular models that can be used to gain information about the effect of a molecule on ion channels. Given the potential interest of many research groups in the highly biodiverse region of Central and South America, we reviewed the most relevant conceptual and methodological developments required to implement the evaluation of the effect of peptide toxins on mammalian voltage-gated ion channels using patch-clamp. For that, we searched MEDLINE/PubMed and SciELO databases with different combinations of these descriptors: "electrophysiology", "patch-clamp techniques", "Ca2+ channels", "K+ channels", "cnidarian venoms", "cone snail venoms", "scorpion venoms", "spider venoms", "snake venoms", "cardiac myocytes", "dorsal root ganglia", and summarized the literature as a scoping review. First, we present the basics and recent advances in mammalian voltage-gated ion channel's structure and function and update the most important animal sources of channel-modulating toxins (e.g. cnidarian and cone snails, scorpions, spiders, and snakes), highlighting the properties of toxins electrophysiologically characterized in Central and South America. Finally, we describe the local experience in implementing the patch-clamp technique using two models of excitable cells, as well as the participation in characterizing new modulators of ion channels derived from the venom of a local spider, a toxins' source less studied with electrophysiological techniques. Fostering the implementation of electrophysiological methods in more laboratories in the region will strengthen our capabilities in many fields, such as toxinology, toxicology, pharmacology, natural products, biophysics, biomedicine, and bioengineering.