Calix[6]arene dismantles extracellular vesicle biogenesis and metalloproteinases that support pancreatic cancer hallmarks.

Many challenges are faced in pancreatic cancer treatment due to late diagnosis and poor prognosis because of high recurrence and metastasis. Extracellular vesicles (EVs) and matrix metalloproteinases (MMPs), besides acting in intercellular communication, are key players in the cancer cell plasticity responsible for initiating metastasis. Therefore, these entities provide valuable targets for the development of better treatments. In this context, this study aimed to evaluate the potential of calix[6]arene to disturb the release of EVs and the activity of MMPs in pancreatic cancer cells. We found a correlation between the endocytic-associated mediators and the prognosis of pancreatic cancer patients. We observed a more active EV machinery in the pancreatic cancer cell line PANC-1, which was reduced three-fold by treatment with calix[6]arene at subtoxic concentration (5 µM; p ã€ˆ0,001). We observed the modulation of 186 microRNAs (164 miRNAs upregulated and 22 miRNAs downregulated) upon calix[6]arene treatment. Interestingly, some of them as miR-4443 and miR-3909, regulates genes HIF1A e KIF13A that are well known to play a role in transport of vesicles. Furthermore, Calix[6]arene downmodulated matrix metalloproteinases (MMPs) -2 and - 9 and disturbed the viability of pancreatic organoids which recapitulate the cellular heterogeneity, structure, and functions of primary tissues. Our findings shed new insights on calix[6]arene's antitumor mechanism, including its intracellular effects on vesicle production and trafficking, as well as MMP activity, which may harm the tumor microenvironment and contribute to a reduction in cancer cell dissemination, which is one of the challenges associated with high mortality in pancreatic cancer.

Synergizing structure and function: Cinnamoyl hydroxamic acids as potent urease inhibitors.

The current investigation encompasses the structural planning, synthesis, and evaluation of the urease inhibitory activity of a series of molecular hybrids of hydroxamic acids and Michael acceptors, delineated from the structure of cinnamic acids. The synthesized compounds exhibited potent urease inhibitory effects, with IC50 values ranging from 3.8 to 12.8 µM. Kinetic experiments unveiled that the majority of the synthesized hybrids display characteristics of mixed inhibitors. Generally, derivatives containing electron-withdrawing groups on the aromatic ring demonstrate heightened activity, indicating that the increased electrophilicity of the beta carbon in the Michael Acceptor moiety positively influences the antiureolytic properties of this compounds class. Biophysical and theoretical investigations further corroborated the findings obtained from kinetic assays. These studies suggest that the hydroxamic acid core interacts with the urease active site, while the Michael acceptor moiety binds to one or more allosteric sites adjacent to the active site.

Exposure to the psychedelic substance 25 H-NBOMe disrupts maternal care in lactating rats and subsequently impairs the social play behavior of the offspring.

Given the critical role of maternal care in the neurodevelopment of offspring, this study aimed to investigate the effects of the psychedelic substance 25 H-NBOMe on maternal behavior in lactating rats and its subsequent impact on the social and neurodevelopmental behavior of the offspring. We administered two different dosages of 25 H-NBOMe (0.3 mg/kg and 1.0 mg/kg; i,p,) to lactating rats and observed changes in maternal behaviors, such as nest-building and pup retrieval, and in offspring behaviors, including social play. Behavioral assessments were complemented by physiological measurements to rule out general health or nutritional decline. 25 H-NBOMe significantly disrupted maternal behaviors, including nest-building and pup retrieval, without affecting the weight of dams or offspring. Offspring of exposed dams exhibited reduced social play behavior. Higher doses led to more pronounced disruptions, while lower doses, despite not visibly affecting maternal behavior, still impacted offspring behavior, suggesting potential direct effects of 25 H-NBOMe. The study highlights the potential risks associated with the use of 25 H-NBOMe during lactation, emphasizing its detrimental impact on maternal care and offspring development. These findings contribute to understanding the neurobiological effects of psychedelic substances during critical developmental periods and underscore the importance of avoiding their use.

New anti-SARS-CoV-2 aminoadamantane compounds as antiviral candidates for the treatment of COVID-19.

Here, the antiviral activity of aminoadamantane derivatives were evaluated against SARS-CoV-2. The compounds exhibited low cytotoxicity to Vero, HEK293 and CALU-3 cells up to a concentration of 1,000 µM. The inhibitory concentration (IC50) of aminoadamantane was 39.71 µM in Vero CCL-81 cells and the derivatives showed significantly lower IC50 values, especially for compounds 3F4 (0.32 µM), 3F5 (0.44 µM) and 3E10 (1.28 µM). Additionally, derivatives 3F5 and 3E10 statistically reduced the fluorescence intensity of SARS-CoV-2 protein S from Vero cells at 10 µM. Transmission microscopy confirmed the antiviral activity of the compounds, which reduced cytopathic effects induced by the virus, such as vacuolization, cytoplasmic projections, and the presence of myelin figures derived from cellular activation in the face of infection. Additionally, it was possible to observe a reduction of viral particles adhered to the cell membrane and inside several viral factories, especially after treatment with 3F4. Moreover, although docking analysis showed favorable interactions in the catalytic site of Cathepsin L, the enzymatic activity of this enzyme was not inhibited significantly in vitro. The new derivatives displayed lower predicted toxicities than aminoadamantane, which was observed for either rat or mouse models. Lastly, in vivo antiviral assays of aminoadamantane derivatives in BALB/cJ mice after challenge with the mouse-adapted strain of SARS-CoV-2, corroborated the robust antiviral activity of 3F4 derivative, which was higher than aminoadamantane and its other derivatives. Therefore, aminoadamantane derivatives show potential broad-spectrum antiviral activity, which may contribute to COVID-19 treatment in the face of emerging and re-emerging SARS-CoV-2 variants of concern.

Comprehensive detection of lysergic acid diethylamide (LSD) in forensic samples using carbon nanotube screen-printed electrodes.

Lysergic acid diethylamide (LSD) is a prevalent psychoactive substance recognized for its hallucinogenic properties, often encountered in blotter papers for illicit consumption. Given that LSD ranks among the most widely abused illicit drugs globally, its prompt identification in seized samples is vital for forensic investigations. This study presents, for the first time, an electrochemical screening method for detecting LSD in forensic samples, utilizing a multi-wall carbon nanotube screen-printed electrode (SPE-MWCNT). The LSD detection process was optimized on SPE-MWCNT in a phosphate buffer solution (0.1 mol L-1, pH 12.0) using square wave voltammetry (SWV). The combined use of SPE-MWCNT with SWV displayed robust stability in electrochemical responses for both qualitative (peak potential) and quantitative (peak current) LSD assessment, with a relative standard deviation (RSD) of less than 5% across the same or different electrodes (N = 3). A linear detection range was established between 0.16 and 40.0 µmol L-1 (R2 = 0.998), featuring a low limit of detection (LOD) of 0.05 µmol L-1. Interference studies with twenty-three other substances, including groups of phenethylamines typically found in blotting papers (e.g., NBOHs and NBOMes) and traditional illicit drugs, were performed, revealing a highly selective response for LSD using the proposed method. Consequently, the integration of SPE-MWCNT with SWV offers a robust tool for qualitative and quantitative LSD analysis in forensic applications, providing rapid, sensitive, selective, reproducible, and straightforward preliminary identification in seized samples.

Neurotoxic effects of hallucinogenic drugs 25H-NBOMe and 25H-NBOH in organotypic hippocampal cultures.

Introduction: NBOMes and NBOHs are psychoactive drugs derived from phenethylamines and have hallucinogenic effects due to their strong agonism to serotonin 5-HT2A receptors. Although cases of toxicity associated with the recreational use of substituted phenethylamines are frequently reported, there is a lack of information on the possible neurotoxic effects of NBOMe and NBOH in the brain hippocampus, a major neurogenesis region. Objectives: This study aimed at assessing the phenotypic and molecular effects of prolonged exposure of the hippocampus to the drugs 25H-NBOMe and 25H-NBOH. Methods: The ex vivo organotypic culture model of hippocampal slices (OHC) was used to investigate, by immunofluorescence and confocal microscopy, and transcriptome analyses, the mechanisms associated with the neurotoxicity of 25H-NBOMe and 25H-NBOH. Results: Reduction in the density of mature neurons in the OHCs occurred after two and seven days of exposure to 25H-NBOMe and 25H-NBOH, respectively. After the withdrawal of 25H-NBOMe, the density of mature neurons in the OHCs stabilized. In contrast, up to seven days after 25H-NBOH removal from the culture medium, progressive neuron loss was still observed in the OHCs. Interestingly, the exposure to 25H-NBOH induced progenitor cell differentiation, increasing the density of post-mitotic neurons in the OHCs. Corroborating these findings, the functional enrichment analysis of differentially expressed genes in the OHCs exposed to 25H-NBOH revealed the activation of WNT/Beta-catenin pathway components associated with neurogenesis. During and after the exposure to 25H-NBOMe or 25H-NBOH, gene expression patterns related to the activation of synaptic transmission and excitability of neurons were identified. Furthermore, activation of signaling pathways and biological processes related to addiction and oxidative stress and inhibition of the inflammatory response were observed after the period of drug exposure. Conclusion: 25H-NBOMe and 25H-NBOH disrupt the balance between neurogenesis and neuronal death in the hippocampus and, although chemically similar, have distinct neurotoxicity mechanisms.

Psychoactive substances 25H-NBOMe and 25H-NBOH induce antidepressant-like behavior in male rats.

Ring-substituted phenethylamines are believed to induce psychedelic effects primarily by interacting with 5-hydroxytryptamine 2 (5-HT2A) receptors in the brain. We assessed the effect of the psychedelic substances 25H-NBOMe and 25H-NBOH on the depressive-like behavior of male adult rats. Naive Wistar rats were divided into groups to assess the effects of different doses (0.1 mg/kg, 1 mg/kg, and 3 mg/kg) of 25H-NBOMe and 25H-NBOH. The substances were administered intraperitoneally and the hallucinogenic properties were evaluated using the head twitch response test (HTR). Additionally, we assessed their locomotor activity in the open field test (OFT) and depressive-like behavior in the forced swimming test (FST). Our data demonstrated that all doses of synthetic psychedelic substances evaluated exhibited hallucinogenic effects. Interestingly, we observed that both 25H-NBOMe and 25H-NBOH produced a significantly greater motivation to escape in the FST, compared to the control group. Furthermore, we found no significant differences in locomotor activity during the OFT, except for the dose of 3 mg/kg, which induced a reduction in locomotion. This study provides new insights into a potential psychedelic substance, specifically by demonstrating the previously unknown antidepressant properties of a single dose of both 25H-NBOMe and 25H-NBOH. These findings contribute to the ongoing progress of experimental psychiatry toward developing safe and effective clinical practices in the field of psychedelics research.

The influence of N-alkyl chains in benzoyl-thiourea derivatives on urease inhibition: Soil studies and biophysical and theoretical investigations on the mechanism of interaction.

Ureases are enzymes produced by fungi, plants, and bacteria associated with agricultural and clinical problems. The urea hydrolysis in NH3 and CO2 leads to the loss of N-urea fertilizers in soils and changes the human stomach microenvironment, favoring the colonization of H. pylori. In this sense, it is necessary to evaluate potential enzyme inhibitors to mitigate the effects of their activities and respond to scientific and market demands to produce fertilizers with enhanced efficiency. Thus, biophysical and theoretical studies were carried out to evaluate the influence of the N-alkyl chain in benzoyl-thiourea derivatives on urease enzyme inhibition. A screening based on IC50, binding constants, and theoretical studies demonstrated that BTU1 without the N-alkyl chain (R = H) was more active than other compounds, so the magnitude of the interaction was determined as BTU1 > BTU2 > BTU3 > BTU4 > BTU5, corresponding to progressively increased chain length. Thus, BTU1 was selected for interaction and soil application essays. The binding constants (Kb) for the supramolecular urease-BTU1 complex ranged from 7.95 to 5.71 × 103 M-1 at different temperatures (22, 30, and 38 °C), indicating that the preferential forces responsible for the stabilization of the complex are hydrogen bonds and van der Waals forces (ΔH = -15.84 kJ mol-1 and ΔS = -36.61 J mol-1 K-1). Theoretical and experimental results (thermodynamics, synchronous fluorescence, and competition assay) agree and indicate that BTU1 is a mixed inhibitor. Finally, urease inhibition was evaluated in the four soil samples, where BTU1 was as efficient as NBPT (based on ANOVA two-way and Tukey test with 95% confidence), with an average inhibition of 20% of urease activity. Thus, the biophysics and theoretical studies are strategies for evaluating potential inhibitors and showed that increasing the N-alkyl chain in benzoyl-thiourea derivatives did not favor urease inhibition.

Understanding the multifunctionality of pyroligneous acid from waste biomass and the potential applications in agriculture.

Efforts have been directed to the development of environmentally friendly processes and manufacturing of green products, use of renewable energy and more sustainable agricultural practices. Pyroligneous acid (PA) is a byproduct of biomass pyrolysis that consists of a complex mixture of bioactive substances. The complexity and richness of PA composition have opened a window for PA application in agriculture and mitigation of environmental pollution. This review brings a brief historical on the use of PA and regulatory policies adopted in Brazil, China, Japan and Thailand for PA application in agriculture. The composition and stability of PAs of several origins are presented, together with a discussion of the use of PA to boost plant growth and crop productivity, remove toxic metals from soil, inhibit soil ureases, mitigate the emission of greenhouse gases, control phytopathogen proliferation and weed dissemination. A great variety of biomass types are reported as feedstock to produce PA with distinct chemically diverse and active substances at wide-ranging concentrations. PA has been shown to successfully improve farming practices in a more sustainable fashion. The disclosure of the mechanisms of action that drive the PA's effects, together with the pursue of safety and efficacy data in a case-by-case way to address toxicity and shelf stability, will be valuable to expand the use of PA worldwide for food production.

Inclusion complex of ketoconazole and p-sulfonic acid calix[6]arene improves antileishmanial activity and selectivity against Leishmania amazonensis and Leishmania infantum.

Many previous studies presented the effectiveness of ketoconazole (KTZ) against leishmaniasis. However, the bioavailability and therapeutic efficacy of free KTZ are limited due to its low aqueous solubility. In this study, an inclusion complex (IC6HKTZ) was prepared with p-sulfonic acid calix[6]arene (CX6SO3H) to improve the solubility and efficacy of KTZ against Leishmania amazonensis and Leishmania infantum promastigotes. A linear increase in KTZ solubility as a function of CX6SO3H concentration was verified using the phase-solubility diagram. The resulting diagram was classified as AL-type and a 1:1 host-guest stoichiometry was assumed to prepare IC6HKTZ by freeze-drying. FTIR, TG/DSC, XRD, and solid-state 13C NMR spectroscopy analyses were performed to confirm the formation of IC6HKTZ. The solubility enhancement of KTZ by 120.00 µM CX6SO3H was about 95 times. The IC50 values of IC6HKTZ and free KTZ were 3.95 and 14.35 µM for Leishmania amazonensis and 6.74 and 17.47 µM for Leishmania infantum, respectively. The viability of DH82 macrophages was not affected by CX6SO3H. These results show that CX6SO3H is a new supramolecular carrier system that improves antileishmanial activities to KTZ for the treatment of cutaneous and visceral leishmaniasis.

Safety and immunogenicity of the anti-cocaine vaccine UFMG-VAC-V4N2 in a non-human primate model.

A promising strategy for cocaine addiction treatment is the anti-drug vaccine. These vaccines induce the production of anticocaine antibodies, capable of linking to cocaine, and decrease the passage of cocaine throughout the blood-brain barrier, decreasing drug activity in the brain. Our research group developed a new vaccine candidate, the UFMG-V4N2, to treat cocaine use disorders (CUD) using an innovative carrier based on calixarenes. This study assessed the safety and immunogenicity of the anti-cocaine vaccine UFMG-VAC-V4N2 in a non-human primate toxicity study using single and multiple vaccine doses. The UFMG-VAC-V4N2 yielded only mild effects in the injection site and did not influence the general health, feeding behavior, or hematological, renal, hepatic, or metabolic parameters in the vaccinated marmosets. The anti-cocaine vaccine UFMG-VAC-V4N2 presented a favorable safety profile and induced the expected immune response in a non-human primate model of Callithrix penicillata. This preclinical UFMG-VAC-V4N2 study responds to the criteria required by international regulatory agencies contributing to future anticocaine clinical trials of this anti-cocaine vaccine.

Synthesis of 2-(2-(4-thioxo-3H-1,2-dithiole-5-yl) phenoxy)ethyl)isoindole-1,3-thione, a novel hydrogen sulfide-releasing phthalimide hybrid, and evaluation of its activity in models of inflammatory pain.

Hydrogen sulfide (H2S) is a gaseous mediator that modulates several physiological and pathological processes. Phthalimide analogues, substances that have the phthalimide ring in the structure, belong to the group of thalidomide analogues. Both H2S donors and phthalimide analogues exhibit activities in models of inflammation and pain. As molecular hybridization is an important strategy aiming to develop drugs with a better pharmacological profile, in the present study we synthesized a novel H2S-releasing phthalimide hybrid, 2-(2-(4-thioxo-3H-1,2-dithiole-5-yl) phenoxy)ethyl)isoindole-1,3-thione (PTD-H2S), and evaluated its activity in models of inflammatory pain in mice. Per os (p.o.) administration of PTD-H2S (125 or 250 mg/kg) reduced mechanical allodynia induced by carrageenan and lipopolysaccharide. Intraperitoneal (i.p.) administration of PTD-H2S (25 mg/kg), but not equimolar doses of its precursors 5-(4-hydroxyphenyl)-3H-1,2-dithiole-3-thione (14.2 mg/kg) and 2-phthalimidethanol (12 mg/kg), reduced mechanical allodynia induced by lipopolysaccharide. The antiallodynic effect induced by PTD-H2S (25 mg/kg, i.p.) was more sustained than that induced by the H2S donor NaHS (8 mg/kg, i.p.). Previous administration of hydroxocobalamin (300 mg/kg, i.p.) or glibenclamide (40 mg/kg, p.o.) attenuated PTD-H2S antiallodynic activity. In conclusion, we synthesized a novel H2S-releasing phthalimide hybrid and demonstrated its activity in models of inflammatory pain. PTD-H2S activity may be due to H2S release and activation of ATP-sensitive potassium channels. The demonstration of PTD-H2S activity in models of pain stimulates further studies aiming to evaluate H2S-releasing phthalimide hybrids as candidates for analgesic drugs.

Thiohydantoins and hydantoins derived from amino acids as potent urease inhibitors: Inhibitory activity and ligand-target interactions.

We report the investigation of hydantoins and thiohydantoins derived from L and d-amino acids as inhibitors against the Canavalia ensiformis urease (CEU). The biochemical in vitro assay against CEU revealed a promising inhibitory potential for most thiohydantoins with six of them showing %I higher than the reference inhibitor thiourea (56.5%). In addition, thiohydantoin derived from l-valine, 1b, as well as the hydantoin 2d, derived from l-methionine, were identified as the most potent inhibitors with %I = 90.5 and 85.9 respectively. Enzyme kinetic studies demonstrated a mixed and uncompetitive inhibition profile for these compounds with Ki values of 0.42 mM for 1b and 0.99 mM for 2d. These kinetic parameters, obtained from traditional colorimetric assay, were strictly related to the KD values measured spectroscopically by the Saturation Transfer Difference (STD) technique for the urease complex. STD was also used to evince the moieties of the ligands responsible for the binding with the enzyme. Molecular docking studies showed that the thiohydantoin and hydantoin rings can act as a pharmacophoric group due to their binding affinity by hydrogen bonding interactions with critical amino acid residues in the enzyme active and/or allosteric site. These findings agreed with the experimental alpha values, demonstrating that 1b has affinity by free enzyme, and 2d derivative, an uncompetitive inhibitor, has great binding affinity at the allosteric site. The results for the thiohydantoin 1a, derived from d-valine, demonstrated a drastic stereochemical influence on inhibition, kinetics, and binding parameters in comparison to its enantiomer 1b.

Calix[n]arene-based immunogens: A new non-proteic strategy for anti-cocaine vaccine.

Introduction: Cocaine use disorder is a significant public health issue without a current specific approved treatment. Among different approaches to this disorder, it is possible to highlight a promising immunologic strategy in which an immunogenic agent may reduce the reinforcing effects of the drug if they are able to yield sufficient specific antibodies capable to bind cocaine and/or its psychoactive metabolites before entering into the brain. Several carriers have been investigated in the anti-cocaine vaccine development; however, they generally present a very complex chemical structure, which potentially hampers the proper assessment of the coupling efficiency between the hapten units and the protein structure. Objectives: The present study reports the design, synthesis and preclinical evaluation of two novel calix[n]arene-based anti-cocaine immunogens (herein named as V4N2 and V8N2) by the tethering of the hydrolysis-tolerant hapten GNE (15) on calix[4]arene and calix[8]arene moieties. Methods: The preclinical assessment corresponded to the immunogenicity and dose-response evaluation of V4N2 and V8N2. The potential of the produced antibodies to reduce the passage of cocaine analogue through the blood-brain-barrier (BBB), modifying its biodistribution was also investigated. Results: Both calix[n]arene-based immunogens elicited high titers of cocaine antibodies that modified the biodistribution of a cocaine radiolabeled analogue (99mTc-TRODAT-1) and decreased cocaine-induced behavior, according to an animal model. Conclusion: The present results demonstrate the potential of V4N2 and V8N2 as immunogens for the treatment of cocaine use disorder.

Ketoconazole/calix[n]arenes-based compounds improve the antifungal activity against azole-resistant Candida isolates.

Ketoconazole (KTZ) is an antifungal agent; however, its bioavailability and therapeutic efficacy are reduced by the low aqueous solubility of the drug. Aiming at providing to improve the biopharmaceutical properties of KTZ, we studied the water-soluble different calix[n]arenes as carrier systems for KTZ. All calix[n]arene-KTZ tested showed in vitro antifungal activity superior or similar to free KTZ against Candida spp. The CX6Na/KTZ obtained by physical mixture and freeze-drying methods were the most active, decreasing KTZ concentrations required for growth inhibition against azole-resistant isolates (e.g., C. auris). Moreover, CX6Na/KTZ showed no toxic effect on Galleria mellonella larvae and the treatment of infected larvae with C. albicans and C. auris was effective at a lower dose compared with free KTZ. Thus, CX6Na/KTZ may have a potential approach to treat mycosis, especially by improvement of KTZ inhibitory activity against azole-resistant Candida.

The new psychoactive substances 25H-NBOMe and 25H-NBOH induce abnormal development in the zebrafish embryo and interact in the DNA major groove.

Toxicological effects of 25H-NBOMe and 25H-NBOH recreational drugs on zebrafish embryos and larvae at the end of 96 h exposure period were demonstrated. 25H-NBOH and 25H-NBOMe caused high embryo mortality at 80 and 100 µg mL-1, respectively. According to the decrease in the concentration tested, lethality decreased while non-lethal effects were predominant up to 10 and 50 µg mL-1 of 25H-NBOH and 25H-NBOMe, respectively, including spine malformation, egg hatching delay, body malformation, otolith malformation, pericardial edema, and blood clotting. We can disclose that these drugs have an affinity for DNA in vitro using biophysical spectroscopic assays and molecular modeling methods. The experiments demonstrated that 25H-NBOH and 25H-NBOMe bind to the unclassical major groove of ctDNA with a binding constant of 27.00 × 104 M-1 and 5.27 × 104 M-1, respectively. Furthermore, these interactions lead to conformational changes in the DNA structure. Therefore, the results observed in the zebrafish embryos and DNA may be correlated.

Special issue: The Brazilian Meeting on Organic Synthesis.

The 18th Brazilian Meeting on Organic Synthesis (18th BMOS) was planned to be held in Tiradentes, Brazil from October 2020. Due to the pandemic caused by the new coronavirus, the event was initially postponed until 2021 and will finally take place in late 2022. This Special Collection of The Chemical Record is organized together with Guest Editors Ângelo de Fátima and Eufrânio N. da Silva Júnior from Federal University of Minas Gerais and features contributions by present and previous participants of the conferene in the field of Organic Synthesis.

The GNE-KLH anti-cocaine vaccine protects dams and offspring from cocaine-induced effects during the prenatal and lactating periods.

Protecting children from prenatal cocaine exposure is a significant challenge for physicians and childbearing women with cocaine use disorder. Cocaine use is highly prevalent among reproductive-aged women and prenatal cocaine exposure produces obstetric, foetal neurodevelopmental and long-term behavioural impairments. Cocaine crosses the maternal and foetal blood-brain barrier and the placenta by diffusion. The best approach to prevent prenatal cocaine exposure is to stop cocaine use. However, only 25% of cocaine users can discontinue their use during pregnancy. Anti-cocaine vaccination decreases cocaine passage through the blood-brain barrier. This study describes an innovative approach for preventing prenatal cocaine exposure using the GNE-KLH anti-cocaine vaccine, a novel use for the named anti-drug vaccines. Here, we show that anti-cocaine vaccination with GNE-KLH produced and maintained anti-cocaine IgG antibody titres and avidity during pregnancy. These antibodies protected the pregnant rats and their pups against prenatal cocaine damage during pregnancy until weaning. The present work is the first preclinical evidence of the efficacy of an innovative mechanism to prevent prenatal cocaine exposure damage, a worldwide public health care issue. In the future, this mechanism may be useful in pregnant women with cocaine use disorder. Further studies to understand the mechanisms of how anti-cocaine antibodies exert their protective effects in pregnancy are warranted.

Paper-based analytical device with colorimetric detection for urease activity determination in soils and evaluation of potential inhibitors.

Urease is an enzyme associated with the degradation of urea, an important nitrogen fertilizer in agriculture. Thus, this current report describes the use of a paper-based analytical device (UrePAD) designed to contain a microzone array for colorimetric determination of urease activity in soils in the absence/presence of potential enzyme inhibitors. The UrePAD can be used at the point-of-need (point-of-care), and it offers advantages such as low cost, simplicity in handling, low sample/reagent volumes, and no use of toxic reagents. The acid-base indicator phenol red was used to monitor the urea hydrolysis reaction catalyzed by urease in the evaluated systems. The images were digitalized in a bench scanner, and the analysis was performed using Corel Draw X8 software. The device offered a LOD of 0.10 U mL-1 with linearity between 0.25 and 4.0 U mL-1 and a relative standard deviation ≤ 1.38%. UrePAD was tested in four soil samples of different characteristics and with eight urease inhibitors of varied classes. The results obtained through the proposed device did not differ statistically (95% confidence interval) from those employing the classic method based on the Berthelot reaction, thus indicating that UrePAD was effective for determining urease activity and screening inhibitors, besides showing the capacity to simplify fieldwork involving the application of urea in the soil.