Multitarget nociceptor sensitization by a promiscuous peptide from the venom of the King Baboon spider.

The King Baboon spider, Pelinobius muticus, is a burrowing African tarantula. Its impressive size and appealing coloration are tempered by reports describing severe localized pain, swelling, itchiness, and muscle cramping after accidental envenomation. Hyperalgesia is the most prominent symptom after bites from P. muticus, but the molecular basis by which the venom induces pain is unknown. Proteotranscriptomic analysis of P. muticus venom uncovered a cysteine-rich peptide, δ/κ-theraphotoxin-Pm1a (δ/κ-TRTX-Pm1a), that elicited nocifensive behavior when injected into mice. In small dorsal root ganglion neurons, synthetic δ/κ-TRTX-Pm1a (sPm1a) induced hyperexcitability by enhancing tetrodotoxin-resistant sodium currents, impairing repolarization and lowering the threshold of action potential firing, consistent with the severe pain associated with envenomation. The molecular mechanism of nociceptor sensitization by sPm1a involves multimodal actions over several ion channel targets, including NaV1.8, KV2.1, and tetrodotoxin-sensitive NaV channels. The promiscuous targeting of peptides like δ/κ-TRTX-Pm1a may be an evolutionary adaptation in pain-inducing defensive venoms.

Efficient PAHs Removal and CO2 Fixation by marine microalgae in wastewater using an airlift photobioreactor for biofuel production.

Microalgae cultures have emerged as a promising strategy in diverse areas, ranging from wastewater treatment to biofuel production, thus contributing to the search for carbon neutrality. These photosynthetic organisms can utilize the resources present in wastewater and fix atmospheric CO2 to produce biomass with high energy potential. In this study, the removal efficiency of Polycyclic Aromatic Hydrocarbons (PAHs), CO2 fixation and lipid content in the biomass produced from microalgae grown in airlift photobioreactor were evaluated. Four mesoscale cultures were carried out: Control (Seawater + Conway medium), Treatment A (Oil Produced Water + Poultry Effluent Water), Treatment B (Poultry Effluent Water + Seawater) and Treatment C (Oil Produced Water, Seawater and nutrients). The impact of biostimulation, through the addition of nutrients, on PAHs removal efficiency (up to 90%), CO2 fixation rate (up to 0.20 g L-1 d-1) and the composition of the generated biomass was observed. Primarily, the addition of nitrates to the culture medium impacted CO2 fixation rate of the microalgae. In addition, a direct correlation was observed between PAHs removal and lipid accumulation in the biomass, up to 36% in dry weight, demonstrating microalgae's ability to take advantage of the organic carbon (PAHs) present in the culture medium to generate lipid-rich biomass. The concentration of polysaccharides in the biomass obtained did not exceed 12% on a dry weight basis, and the Higher Heating Value (HHV) ranged between 17 and 21 MJ kg-1. Finally, the potential of generating hydrogen through pyrolysis was highlighted, taking advantage of the characteristics of biomass as a conversion route to produce biofuels. These results show that microalgae are effective in wastewater treatment and have great potential in producing biofuels, thus contributing to the transition towards more sustainable energy sources and climate change mitigation.

Dual-source computed tomography protocols for the pediatric chest - scan optimization techniques.

The gold standard for pediatric chest imaging remains the CT scan. An ideal pediatric chest CT has the lowest radiation dose with the least motion degradation possible in a diagnostic scan. Because of the known inherent risks and costs of anesthesia, non-sedate options are preferred. Dual-source CTs are currently the fastest, lowest-dose CT scanners available, utilizing an ultra-high-pitch mode resulting in sub-second CTs. The dual-energy technique, available on dual-source CT scanners, gathers additional information such as pulmonary blood volume and includes relative contrast enhancement and metallic artifact reduction, features that are not available in high-pitch flash mode. In this article we discuss the benefits and tradeoffs of dual-source CT scan modes and tips on image optimization.

Enhanced Two-Step Extraction from Biomass of Two Cymbopogon Species Cultivated in Santander, Colombia.

The insertion of circular economy principles into the essential oil (EO) production chain aims to reduce waste generation and make integral use of harvested plant material. Higher profits from integral use with reduced waste generation contribute to the eventual use of the EO value chain as an alternative to illicit crops in Colombia (mostly coca). In this study, Java-type citronella (Cymbopogon winterianus) and palmarosa (C. martinii) plant materials were used in two consecutive processes to obtain EOs and extracts. The residual biomass after EO distillation was subjected to ultrasound-assisted hydroethanolic extraction to afford extracts that contained bioactive compounds. Citronella and palmarosa were distilled with typical EO yields (1.0 ± 0.1% for citronella; 0.41 ± 0.06% for palmarosa; n = 5) either through hydrodistillation assisted by microwave radiation or through steam distillation, and their composition (determined via GC/FID/MS analysis) and physicochemical parameters fell within their ISO standard specifications. The concentration of citronellal, the major compound of citronella oil, was 500 ± 152 mg/g. Geraniol, the main component of palmarosa oil, was found at 900 ± 55 mg/g. The citronella and palmarosa hydroalcoholic extracts (4-11% yield) were analyzed with UHPLC-ESI-Orbitrap-MS, which permitted the identification of 30 compounds, mainly C-glycosylated flavones and hydroxycinnamic acids. Both extracts had similar antioxidant activity values, evaluated using the ABTS+● and ORAC assays (110 ± 44 µmol Trolox®/g extract and 1300 ± 141 µmol Trolox®/g extract, respectively).

Administration of Single-Dose Antibiotic Does Not Decrease Oronasal Fistula Rates After Primary Palatoplasty.

OBJECTIVE: Oronasal fistula (ONF) is a known complication after primary palatoplasty (PP). Studies investigating the effect of perioperative antibiotics on fistula rates after PP are limited by inadequate sample size or reliance on self-reporting through national databases. In this study, the authors evaluated the association between single-dose perioperative antibiotics and postoperative fistula rates after PP at a single institution. DESIGN: A retrospective study. PARTICIPANTS: Children younger than 2 years who underwent PP from April 2009 to September 2019 were included. INTERVENTIONS: Patients were divided into 2 categories: Group 1 received a single intraoperative dose of IV antibiotic, while group 2 did not. MAIN OUTCOME MEASURE(S): Outcome measures included ONF formation, length of stay (LOS), and 30-day readmission rates. Multivariable firth logistic regression, quantile regression, and χ2 tests were performed. RESULTS: Of the 424 patients, 215 and 209 patients were in groups 1 and 2, respectively. The overall ONF rate was 1.9% among all patients. Patients in group 1 experienced an ONF rate of 3.3%, while patients in group 2 had an ONF rate of 0.5%. After correcting for confounding variables, the difference in ONF rates was not statistically different (P = .68). Median LOS was 35.7 hours and 35.5 hours (P = .17), while the rate of readmission within 30 days was 4.7% and 2.4% for group 1 and 2, respectively (P = .96). CONCLUSIONS: Administration of a single-dose perioperative antibiotic did not decrease fistula formation after PP, nor did it affect the patient's LOS or 30-day readmission rate.

Virulence Conferred by PumA Toxin from the Plasmid-Encoded PumAB Toxin-Antitoxin System is Regulated by Quorum System.

Toxin-antitoxin (TA) systems are small genetic elements composed of a toxin gene and its cognate antitoxin that are important for plasmid stabilization (plasmid-encoded) and bacterial virulence (chromosome-encoded). These systems are also related to biofilm and persister cell formations. Pseudomonas aeruginosa is an antibiotic-resistant human pathogen that produces virulence factors modulated by quorum sensing (QS) and can form biofilms. The type II PumAB TA system of pUM505, isolated from a clinical strain of P. aeruginosa, confers plasmid stability. Additionally, the PumA toxin increases P. aeruginosa virulence and is neutralized by the PumB antitoxin. In this study, we determined whether virulence conferred by PumA toxin is regulated by QS. The pumA gene was transferred to P. aeruginosa lasI/rhlI, a mutant strain in the LasI and RhlI QS systems, to analyze the effect on virulence of the transformants. pumA transfer did not increase bacterial virulence in lettuce and Caenorhabditis elegans, suggesting that the virulence conferred by PumA requires QS modulation. pumA mRNA levels drastically decreased in the P. aeruginosa lasI/rhlI (pUC_pumA) strain, suggesting positive regulation of pumA gene expression by QS. Supplementation of the growth medium of P. aeruginosa lasI/rhlI (pUC_pumA) with C4-AHL and 3-oxo-C12-AHL autoinducers increased pumA mRNA levels and restored bacterial virulence, suggesting that both autoinducers complemented the mutations and positively regulated the toxic effects of PumA. This strengthened the hypothesis that QS regulates bacterial virulence conferred by the PumA toxin. Thus, this report establishes an important function of QS in the virulence conferred by plasmid-encoded TA systems in bacterial pathogens.

Prevalence of the crpP gene conferring decreased ciprofloxacin susceptibility in enterobacterial clinical isolates from Mexican hospitals.

OBJECTIVES: This study investigated the presence of the crpP gene, which encodes an enzymatic mechanism of antibiotic phosphorylation that decreases ciprofloxacin susceptibility, in ESBL-producing clinical isolates and its effect in transconjugants. METHODS: A collection of 77 ESBL-producing clinical isolates of Enterobacteriaceae and 68 ESBL-producing transconjugants that had acquired plasmids from clinical isolates from hospitals in Mexico obtained from 1988 to 2012 was employed. The crpP homologue genes were identified by dot-blot and PCR assays; five of them were sequenced and an in silico analysis was conducted. Expression of CrpP proteins was determined by western blot assays using antibodies against CrpP from plasmid pUM505. Three crpP homologue genes were cloned and transferred to Escherichia coli J53-3 as recipient strain. RESULTS: The crpP gene was identified in four (5.19%) ESBL-producing isolates and five (7.35%) ESBL-producing transconjugants with plasmids from clinical isolates. Analysis of the deduced amino acid (aa) sequence of the CrpP protein homologues revealed that they all corresponded to small proteins (63-70 aa) with an identity of 10.1%-43.7% with respect to the pUM505 CrpP sequence. In addition, all crpP-positive transconjugants expressed a CrpP protein. Finally, transfer of crpP homologues conferred lower ciprofloxacin susceptibility to E. coli. CONCLUSIONS: These findings indicate the presence of crpP genes among ESBL-producing isolates from Mexican hospitals and point to widespread crpP-type genes in old Enterobacteriaceae clinical isolates (from 1994). CrpP probably confers resistance by means of the phosphorylation of ciprofloxacin.

CrpP Is a Novel Ciprofloxacin-Modifying Enzyme Encoded by the Pseudomonas aeruginosa pUM505 Plasmid.

The pUM505 plasmid, isolated from a clinical Pseudomonas aeruginosa isolate, confers resistance to ciprofloxacin (CIP) when transferred into the standard P. aeruginosa strain PAO1. CIP is an antibiotic of the quinolone family that is used to treat P. aeruginosa infections. In silico analysis, performed to identify CIP resistance genes, revealed that the 65-amino-acid product encoded by the orf131 gene in pUM505 displays 40% amino acid identity to the Mycobacterium smegmatis aminoglycoside phosphotransferase (an enzyme that phosphorylates and inactivates aminoglycoside antibiotics). We cloned orf131 (renamed crpP, for ciprofloxacin resistance protein, plasmid encoded) into the pUCP20 shuttle vector. The resulting recombinant plasmid, pUC-crpP, conferred resistance to CIP on Escherichia coli strain J53-3, suggesting that this gene encodes a protein involved in CIP resistance. Using coupled enzymatic analysis, we determined that the activity of CrpP on CIP is ATP dependent, while little activity against norfloxacin was detected, suggesting that CIP may undergo phosphorylation. Using a recombinant His-tagged CrpP protein and liquid chromatography-tandem mass spectrometry, we also showed that CIP was phosphorylated prior to its degradation. Thus, our findings demonstrate that CrpP, encoded on the pUM505 plasmid, represents a new mechanism of CIP resistance in P. aeruginosa, which involves phosphorylation of the antibiotic.

A plasmid-encoded mobile genetic element from Pseudomonas aeruginosa that confers heavy metal resistance and virulence.

Mobile plasmid-encoded elements are DNA segments that are transferred for horizontal gene transfer and that confer adaptive proprieties, as well as virulence and antibiotic and heavy metal resistance to bacteria. The conjugative plasmid pUM505, isolated from a clinical strain of Pseudomonas aeruginosa, possesses a putative 31.292 kb mobile element (denominated Mpe: Mobile plasmid- encoded element) that, in addition to possessing chr genes that confer chromate resistance to Pseudomonas, contains two putative mer operons that could confer mercury resistance. Moreover, the Mpe contains genes related previously with the virulence of both P. aeruginosa and Escherichia coli strains. In this work, we determined that Mpe from pUM505 was able to independently move to another DNA molecule, conferring chromate and mercury resistance to P. aeruginosa PAO1 and mercury resistance to E. coli JM101, suggesting that its transference might be beneficial to bacteria under certain environmental conditions. Additionally, the transference of Mpe increased the virulence of P. aeruginosa PAO1 against the nematode Caenorhabditis elegans, suggesting its contribution to the pathogenicity of P. aeruginosa. In this work, we describe a new mobile plasmid-encoded element that possesses the potential to be transferred by horizontal gene transference, which could provide bacteria with a wide variety of adaptive traits such as heavy metal resistance and virulence, which can be selective factors for the distribution and prevalence of this plasmid in diverse environments, including hospitals and heavy metal contaminated soils.

Low expression of galectin-3 is associated with poor survival in node-positive breast cancers and mesenchymal phenotype in breast cancer stem cells.

BACKGROUND: Galectin-3 (Gal3) plays diverse roles in cancer initiation, progression, and drug resistance depending on tumor type characteristics that are also associated with cancer stem cells (CSCs). Recurrence of breast carcinomas may be attributed to the presence of breast CSCs (BCSCs). BCSCs exist in mesenchymal-like or epithelial-like states and the transition between these states endows BCSCs with the capacity for tumor progression. The discovery of a feedback loop with galectins during epithelial-to-mesenchymal transition (EMT) prompted us to investigate its role in breast cancer stemness. METHOD: To elucidate the role of Gal3 in BCSCs, we performed various in vitro and in vivo studies such as sphere-formation assays, Western blotting, flow cytometric apoptosis assays, and limited dilution xenotransplant models. Histological staining for Gal3 in tissue microarrays of breast cancer patients was performed to analyze the relationship of clinical outcome and Gal3 expression. RESULTS: Here, we show in a cohort of 87 node-positive breast cancer patients treated with doxorubicin-based chemotherapy that low Gal3 was associated with increased lymphovascular invasion and reduced overall survival. Analysis of in vitro BCSC models demonstrated that Gal3 knockdown by small hairpin RNA (shRNA) interference in epithelial-like mammary spheres leads to EMT, increased sphere-formation ability, drug-resistance, and heightened aldefluor activity. Furthermore, Gal3negative BCSCs were associated with enhanced tumorigenicity in orthotopic mouse models. CONCLUSIONS: Thus, in at least some breast cancers, loss of Gal3 might be associated with EMT and cancer stemness-associated traits, predicts poor response to chemotherapy, and poor prognosis.

Membrane interactions and biological activity of antimicrobial peptides from Australian scorpion.

UyCT peptides are antimicrobial peptides isolated from the venom of the Australian scorpion. The activity of the UyCT peptides against Gram positive and Gram negative bacteria and red blood cells was determined. The membrane interactions of these peptides were evaluated by dye release (DR) of the fluorophore calcein from liposomes and isothermal titration calorimetry (ITC); and their secondary structure was determined by circular dichroism (CD). Three different lipid systems were used to mimic red blood cells, Escherichia coli and Staphylococcus aureus membranes. UyCT peptides exhibited broad spectrum antimicrobial activity with low MIC for S. aureus and multi-drug resistant Gram negative strains. Peptide combinations showed some synergy enhancing their potency but not hemolytic activity. The UyCT peptides adopted a helical structure in lipid environments and DR results confirmed that the mechanism of action is by disrupting the membrane. ITC data indicated that UyCT peptides preferred prokaryotic rather than eukaryotic membranes. The overall results suggest that UyCT peptides could be pharmaceutical leads for the treatment of Gram negative multiresistant bacterial infections, especially against Acinetobacter baumanni, and candidates for peptidomimetics to enhance their potency and minimize hemolysis. This article is part of a Special Issue entitled: Interfacially Active Peptides and Proteins. Guest Editors: William C. Wimley and Kalina Hristova.

Structure, molecular modeling, and function of the novel potassium channel blocker urotoxin isolated from the venom of the Australian scorpion Urodacus yaschenkoi.

This communication reports the structural and functional characterization of urotoxin, the first K(+) channel toxin isolated from the venom of the Australian scorpion Urodacus yaschenkoi. It is a basic peptide consisting of 37 amino acids with an amidated C-terminal residue. Urotoxin contains eight cysteines forming four disulfide bridges with sequence similarities resembling the α-potassium channel toxin 6 (α-KTx-6) subfamily of peptides; it was assigned the systematic number of α-KTx-6.21. Urotoxin is a potent blocker of human voltage-gated potassium channel (Kv)1.2 channels, with an IC50 of 160 pM, whereas its affinity for other channels tested was in the nanomolar range (hKv1.1, IC50 = 253 nM; hKv1.3, IC50 = 91 nM; and hKCa3.1, IC50 = 70 nM). The toxin had no effect on hKv1.4, hKv1.5, human ether-à-go-go-related gene type 1 (hERG1), or human ether-à-go-go-like (hELK2) channels. Multiple sequence alignments from the venom gland transcriptome showed the existence of four other new peptides similar to urotoxin. Computer modeling of urotoxin's three-dimensional structure suggests the presence of the α/ß-scaffold characteristic of other scorpion toxins, although very likely forming an uncommon disulfide pairing pattern. Using molecular dynamics, a model for the binding of this peptide to human Kv1.2 and hKv1.1 channels is presented, along with the binding of an in silico mutant urotoxin (Lys25Ala) to both channels. Urotoxin enriches our knowledge of K(+) channel toxins and, due to its high affinity for hKv1.2 channels, it may be a good candidate for the development of pharmacologic tools to study the physiologic functions of K(+) channels or related channelopathies and for restoring axonal conduction in demyelinated axons.

Differing impacts of the COVID-19 pandemic on farmers and intermediaries: insights into the Ecuadorian cocoa value chain.

The COVID-19 pandemic generated diverse impacts and responses in agricultural value chains worldwide. Cocoa is a key crop for Ecuadorian exports, and the analysis of effects the pandemic had on value chain actors contributes to the understanding of their individual capacities to coping with a major shock. The purpose of this study was to assess the number and severity of impacts and responses implemented by two links in the cocoa value chain to the pandemic, based on a survey of 158 cocoa farmers and 52 cocoa intermediaries from the main cocoa-producing provinces of the northern coast of Ecuador in 2021. Surveyed farmers and part of the intermediaries form part of the sustainability program of a large Swiss chocolate manufacturer. The impacts and responses reported were grouped into seven resources according to the Activity System Approach. Then, a comparison between groups was applied using the Wilcoxon rank sum test for nonparametric data, determining the most severe impacts and effective resilience responses among the actors. The results reveal that farmers and intermediaries were similarly affected by the pandemic, reporting 21 and 16 negative impacts, respectively. Farmers experienced a higher number and severity of impacts on financial and social resources, while intermediaries on human and material resources. The strongest impact was the loss of sales, reported by 65% of farmers and 58% of intermediaries. Farmers implemented more social responses that they judged highly effective, while intermediaries implemented more human responses that they judged highly effective. Public policy should enhance the social resources of farmers by strengthening their associativity and the capacities of their members, as mechanisms to mitigate their vulnerability to future health and climate crises. The financial resources of both actors should be protected through public credit and agricultural insurance.

Removal of polycyclic aromatic hydrocarbons (PAHs) from produced water using the microalgae Chlorella vulgaris cultivated in mixotrophic and heterotrophic conditions.

Chlorella vulgaris was cultivated for 15 days in 10 different treatments under mixotrophic and heterotrophic conditions, using wastewater from oil and poultry industries as the culture medium. The blends were made with produced water (PW), sterilized produced water (PWs), sterilized poultry wastewater (PoWs), sterilized seawater (SWs), and the addition of sodium nitrate to evaluate cell growth in treatments and the removal of PAHs. The heterotrophic condition showed more effective removal, having an initial concentration of 3.93 µg L-1 and a final concentration of 0.57 µg L-1 of total PAHs reporting 83%, during phycoremediation of (PW) than the mixotrophic condition, with an initial concentration of 3.93 µg L-1 and a final concentration of 1.96 and 43% removal for the PAHs. In the heterotrophic condition, the blend with (PWs + SWs) with an initial concentration of 0.90 µg L-1 and a final concentration of 0.32 µg L-1 had 64% removal of total PAHs compared to the mixotrophic condition with 37% removal having an initial concentration of 0.90 µg L-1 and a final concentration of 0.56 µg L-1. However, the best result in the mixotrophic condition was obtained using a blend of (PWs + PoWs) that had an initial cell concentration of 1.18 × 105 cells mL-1 and reached a final cell concentration of 4.39 × 105 cells mL-1, an initial concentration of 4.76 µg L-1 and a final concentration of 0.37 µg L-1 having a 92% total removal of PAHs. The biostimulation process increased the percentage of PAHs removal by 45% (PW) in the mixotrophic condition. This study showed that it is possible to allow an environmental remediation strategy that significantly reduces effluent toxicity and generates high value-added biomass in contaminated effluents rich in nutrients and carbon, based on a circular bioeconomy model.

The hard life of an octopus embryo is seen through gene expression, energy metabolism, and its ability to neutralize radical oxygen species.

The reproductive process in Octopus maya was analyzed to establish the amount of reactive oxygen species that the embryos inherit from females, during yolk synthesis. At the same time, respiratory metabolism, ROS production, and the expression of some genes of the antioxidant system were monitored to understand the ability of embryos to neutralize maternal ROS and those produced during development. The results indicate that carbonylated proteins and peroxidized lipids (LPO) were transferred from females to the embryos, presumably derived from the metabolic processes carried out during yolk synthesis in the ovary. Along with ROS, females also transferred to embryos glutathione (GSH), a key element of the antioxidant defense system, thus facilitating the neutralization of inherited ROS and those produced during development. Embryos are capable of neutralizing ROS thanks to the early expression of genes such as catalase (CAT) and superoxide dismutase (SOD), which give rise to the synthesis of enzymes when the circulatory system is activated. Also, it was observed that the levels of the routine metabolic rate of embryos are almost as high as those of the maximum activity metabolism, which leads, on the one hand, to the elevated production of ROS and suggests that, at this stage of the life cycle in octopuses, energy production is maximum and is physically limited by the biological properties inherent to the structure of embryonic life (oxygen transfer through the chorion, gill surface, pumping capacity, etc.). Due to its role in regulating vascularization, a high expression of HIf-1A during organogenesis suggests that circulatory system development has begun in this phase of embryo development. The results indicate that the routine metabolic rate and the ability of O. maya embryos to neutralize the ROS are probably the maximum possible. Under such circumstances, embryos cannot generate more energy to combat the free radicals produced by their metabolism, even when environmental factors such as high temperatures or contaminants could demand excess energy.

Efficacy of Hot Tea Infusion vs. Ethanolic Extract of Moringa oleifera for the Simultaneous Treatment of Nonalcoholic Fatty Liver, Hyperlipidemia, and Hyperglycemia in a Murine Model Fed with a High-Fat Diet.

Moringa oleifera (MO) is a native tree of Asia and is cultivated in some areas of Mexico as part of traditional horticulture. The aim of the present study was to compare the efficacy of MO infusion vs. MO ethanolic extract for the simultaneous treatment of nonalcoholic fatty liver (NAFLD), hyperlipidemia, and hyperglycemia in a murine model fed with a high-fat diet (HFD). BALB/c mice were fed a balanced diet (healthy control) or an HFD for 6 months. With this, the NAFLD model was established before starting a therapeutic intervention with MO for two months. The phytochemical analysis by nuclear magnetic resonance in 1H and 13C experiments showed signals for pyrrole alkaloids and triterpenes as the main constituents of the extract and infusion preparation. A significant reduction of SGPT, SGOT, lipids, urea, and glucose in blood among NAFLD groups treated with MO (infusion or extract) was found, when compared to the NAFLD-placebo group. Steatosis and liver inflammation were found to be decreased in the MO groups, as infusion or ethanolic extract. Infusion produced a better therapeutic effect than the extract in all parameters, except glycemic control, where the extract was better. As an additional finding, it is noteworthy that treatment with MO, particularly through infusion, resulted in improved motor activity. Moreover, a reduction in anxiety-like behavior was observed exclusively with the administration of infusion. These observations provide valuable insights into the potential broader effects of Moringa oleifera beyond the primary aim of the study.

Characterization of cholinesterases in the damselfish Sergeant major (Abudefduf saxatilis).

Cholinesterase (ChE) activity has been used for many years as a biomarker of exposure to organophosphate and carbamate pesticides. Recent studies have demonstrated that there could be biological factors that determine ChE type and levels; thus, juvenile Sergeant major (Abudefduf saxatilis) ChE enzymes were biochemically characterized. ChE enzymes found in the head and trunk were evaluated for their substrate preference and sensitivity to selective inhibitors. The use of the head and trunk was chosen as a strategy to reduce dissection time and to ensure sample uniformity between stations. The results indicated that there are two types of ChE enzymes in the head: acetylcholinesterase (AChE) and atypical butyrylcholinesterase (BChE) that exhibits intermediate characteristics of human AChE and BChE activities. Atypical BChE is predominantly found in the trunk. The results also indicated that the ChE activity found in A. saxatilis may be used as a biomarker in studies monitoring the Mexican Caribbean.

Predictors of Scientific Civic Engagement (PSCE) Survey: A Multidimensional Instrument to Measure Undergraduates' Attitudes, Knowledge, and Intention to Engage with the Community Using Their Science Skills.

Civic engagement is an individual's active participation that is intended to improve a community's socioeconomic status or help shape its future. Undergraduates who engage with a community during formal course work are more likely to participate civically later in life. This outcome is important for science, technology, engineering and math (STEM) students since they use STEM knowledge to make informed decisions about public health, national security and the environment. STEM courses that incorporate this idea actively engage students in helping communities, and yet, assessment of the civic outcomes in these courses, such as measuring important predictors of future civic engagement, has been inconsistent and challenging. To address this need, we designed and assessed a new survey by adapting and testing items from previously existing civic engagement measures. The result was a 14-item survey comprising the following scientific civic constructs, that predict future scientific civic engagement: value, self-efficacy, action, and knowledge. This survey has potential to provide insight into the development of scientific civic engagement for STEM disciplines among undergraduate populations and can be used with additional scales of interest, allowing for researchers to assess relationships between predictors of scientific civic engagement and other constructs.

Epidemiology and clinical features of venomous snake bites in the Northern Amazon of Ecuador (2017-2021) / Epidemiología y características clínicas de las mordeduras de serpientes venenosas en el norte de la Amazonía del Ecuador (2017-2021)

Introduction: In Ecuador, poisonous snakebites are a public health problem. However, there is no recent hospital information from the Amazon. Objective: To retrospectively analyse the clinical-epidemiological characteristics of snakebites in patients admitted to a hospital in the Ecuadorian Amazon. Materials and methods: This is a cross-sectional study conducted at the Nueva Loja-Sucumbíos Provincial Hospital, bordering Colombia (2017-2021). Demographic, epidemiological and clinical variables, and condition at hospital discharge, were obtained from the epidemiological file of the Ministerio de Salud Pública. Results: In 5 years, 147 patients (29.4 per year) were hospitalized with no mortality. They corresponded to 26, 34, 32, 29 and 26 cases, in 2017, 2018, 2019, 2020 and 2021, respectively. Men with 99 (67.3%), aged 21-30 years with 28, mixed race with 94 cases, students, and farmers, were the most affected. The most affected (99; 67.3%) were men, people 21 to 30 years-old (28; 19.0%), mestizos (94; 63.9%), students, and farmers. The median age was 28 (range: 4-81) years. Prevalence was higher in April, June, and September. All accidents were caused by Viperidae snakes. Twenty (13.6%) cases were mild, (61.2%) were moderate and 37 (25.2%) were severe. The feet with 45 were the most bitten. Pre-hospitalization anti-venom serum was received by 53.1% and tourniquet by 19.8% patients. Median hospital arrival time was 5 (range 1-192) hours, mostly between 2-3 hours with 41 cases. No statistically significant differences were found considering the severity. Conclusions: A high prevalence of snakebites was evidenced in the north of the Amazon in Ecuador, with a higher incidence in the rainy season and all by Viperidae species. It is important to highlight the null mortality. Information campaigns on prevention and first aid, such as discouraging the use of tourniquets, especially among vulnerable groups.

Introducción. En Ecuador, las mordeduras de serpientes venenosas son un problema de salud pública. Sin embargo, no existe información hospitalaria reciente desde la Amazonía. Objetivo. Analizar retrospectivamente las características clínico-epidemiológicas de las mordeduras de serpientes en pacientes ingresados en un hospital de la Amazonía del Ecuador. Materiales y métodos. Se llevó a cabo un estudio transversal en el hospital provincial de Nueva Loja (Sucumbíos), que colinda con Colombia, 2017-2021. La información sobre las variables demográficas, epidemiológicas y clínicas, y la condición al egreso hospitalario, se obtuvieron de la ficha epidemiológica del Ministerio de Salud Pública. Resultados. En cinco años se hospitalizaron 147 pacientes (29,4 por año), sin que se presentaran muertes. Corresponden a 26, 34, 32, 29 y 26 casos, en el 2017, 2018, 2019, 2020 y 2021, respectivamente. Según el sexo, los más afectados fueron los hombres (n=99; 67,3 %), según el grupo etario, los de 21 a 30 años (n=28; 19,0 %) y, según la raza, los de etnia mestiza (n=94; 63,9 %), estudiantes y agricultores. La mediana de edad fue de 28 años (rango: 4 a 81). Hubo mayor prevalencia en abril, junio y septiembre. Todos los accidentes fueron causados por serpientes Viperidae. Veinte (13,6 %) casos fueron leves, 90 (61,2 %), moderados, y 37 (25,2 %), graves. La mordedura fue más frecuente en los pies (45 casos). El 53,1 % recibió suero antiofídico antes de la hospitalización y en el 19,8 % de los pacientes se colocó un torniquete. La mediana de tiempo de llegada al hospital fue de 5 horas (rango: 1-192), y lo más frecuente fue entre 2 y 3 horas (41 casos). No se encontraron diferencias estadísticamente significativas según la gravedad del caso. Conclusiones. Se evidenció una gran prevalencia de mordeduras de serpientes en el norte de la región amazónica-Ecuador, con mayor incidencia en la estación lluviosa y todas causadas por Viperidae. Es importante resaltar la mortalidad nula. Las campañas informativas sobre prevención y primeros auxilios, como la desmotivación del uso de torniquetes, serían fundamentales para reducir los casos, especialmente, en los grupos vulnerables.

Crystallographic, spectroscopic and thermal studies of 1-(4-bromophenyl)-5-(2,5-dimethyl-1H-pyrrol-1-yl)-3-methyl-1H-pyrazole.

The new title pyrrole-pyrazole derivative, C16H16BrN3, was synthesized through a citric acid-catalyzed Paal-Knorr reaction between acetonylacetone and 1-(4-bromophenyl)-3-methyl-1H-pyrazol-5-amine under mild reaction conditions. This synthetic protocol is noteworthy for its utilization of stoichiometric amounts of the reactants, an ecofriendly solvent and a cost-effective, non-toxic and biodegradable organocatalyst. A comprehensive understanding of the molecular structure was gained through spectroscopic, thermal and X-ray crystallographic analyses. The crystal structure is characterized by weak interactions, where only C-H...π connections contribute to the hydrogen-bond contacts. The supramolecular assembly is controlled by dispersion forces. However, the energy frameworks demonstrate that these forces act in three dimensions, providing enough stability, as observed in TGA-DSC (thermogravimetric analysis-differential scanning calorimetry) studies.