Publications by authors named "Poletto J"

Herein, we introduce an unprecedented cascade reaction for the assembly of pyrrole-fused 1,5-benzodiazepine frameworks. These diverse privileged scaffolds were controllably constructed by intramolecular cyclization of β-enamino diketone, followed by annulation with -phenylenediamine. The protocol features efficient one-pot cascade cyclization/annulation, performed under simple and mild reaction conditions.

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The β-N-methylamino-L-alanine (BMAA) is a neurotoxin produced by cyanobacteria and diatoms and related by triggered neurodegeneration. The exposure to neurotoxins has also been reported by causing emotional and neuroendocrine effects and these effects may be sex-specific. However, the effects of BMAA on emotions and pain, as well as neuroendocrine modulations remain poorly understood.

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Green sturgeon () are an anadromous threatened species of sturgeon found along the Pacific coast of North America. The southern distinct population segment only spawns in the Sacramento River and is exposed to water temperatures kept artificially cold for the conservation and management of winter-run Chinook salmon (). Past research has demonstrated costs of cold-water rearing including reduced growth rates, condition and survivorship of juvenile green sturgeon.

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An efficient and controlled site-selective annulation of 3,5-diethoxycarbonyl 4-hydrazonyl pyrazoles is described. The relative proportion of the products is affected by hydrazone intermediate configuration, reaction temperature, and Lewis acid employed. At a temperature of 110-120 °C, the reaction preferentially afforded 1-pyrazolo[3,4-]pyridazin-7(6)-ones, whereas using Yb(OTf) in MeCN reflux, 2-pyrazolo[3,4-]pyridazin-7(6)-ones were favored.

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Music therapy has long been used as a non-pharmacological intervention to improve cognitive function and mood in humans. Mounting rodent evidence also supports beneficial impact of music exposure on animal cognitive performance. The zebrafish (Danio rerio) is an important emerging aquatic animal model in translational biomedical and neuroscience research.

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A simple, efficient and highly regioselective method for the preparation of 3,4- and 4,5-disubstituted -methylpyrazoles in a one-pot procedure is reported. The methodology developed was based on the regiochemical control of the reaction of 4-acyl-1-pyrrole-2,3-diones and methylhydrazine with an influence of the addition or absence of acid and the substrate structure.

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Objective: Obesity is a disease characterized by the accumulation of abnormal or excessive fat that can damage health. Bariatric surgery, an effective and safe way to treat this disease, requires multidisciplinary monitoring with an educational nature to change lifestyle. Adherence to routine physical activity can be a part of adopting a healthier lifestyle and can assist in the treatment of this disease and its related comorbidities.

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Invited for this month's cover picture is the group of Prof. Fernanda Andreia Rosa at the State University of Maringá (Brazil). The cover picture shows the contribution of the SINTHET research group to the synthesis and discovery of new antiprotozoal compounds.

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A series of 60 4-aminomethyl 5-aryl-3-substituted isoxazoles were synthesized by an efficient method and evaluated in vitro against Leishmania amazonensis and Trypanosoma cruzi, protozoa that cause the neglected tropical diseases leishmaniasis and Chagas disease, respectively. Thirteen compounds exhibited a selective index greater than 10. The series of 3-N-acylhydrazone isoxazole derivatives bearing the bithiophene core exhibited the best antiparasitic effects.

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Trypanosoma cruzi and Leishmania species are causative agents of Chagas disease and Leishmaniasis, respectively, known as Neglected Tropical Diseases. Up to now, the treatments are inadequate and based on old drugs. Thus, we report herein the discovery of 1,3,4,5-tetrasubstituted pyrazole derivatives that presented potent and selective inhibition against promastigote forms of L.

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In this article, a series of 29 new pyrimidine N-acylhydrazone hybrids were synthesized and evaluated in vitro against Leishmania amazonensis and Trypanosoma cruzi protozoa that cause the neglected diseases cutaneous leishmaniasis and Chagas disease, respectively. Eight of the target compounds showed significant antiprotozoal activities with IC values in 4.3-33.

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A simple and efficient methodology for highly regioselective synthesis of azomethine pyrazoles and isoxazoles containing a trifluoromethyl group is reported. The cyclocondensation of trifluoromethylated β-enamino diketones (TBED) with phenylhydrazine and hydroxylamine hydrochloride, in the presence of BF3, provided 5-aryl-4-[(tert-butyl)iminomethyl]-3-trifluoromethylazoles by aza-Michael-type 1,2-addition. The scope of the reaction was expanded by transimination with arylamines in a one-pot method starting from TBED.

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An efficient one-pot method is described for the highly regioselective synthesis of α-ketoamide -arylpyrazoles from secondary β-enamino diketones. For this, the key intermediate, 4-acyl 3,5-dihydroxypyrrolone, was generated in situ and underwent bimolecular nucleophilic substitution at C-5 by arylhydrazine, with subsequent heterocyclization at the carbonyl carbon of the acyl group. This strategy allowed for regiochemical control of α-ketoamide -arylpyrazoles from β-enamino diketones and arylhydrazines.

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Reversing global declines in the abundance and diversity of fishes is dependent on science-based conservation solutions. A wealth of data exist on the ecophysiological constraints of many fishes, but much of this information is underutilized in recovery plans due to a lack of synthesis. Here, we used the imperiled green sturgeon () as an example of how a quantitative synthesis of physiological data can inform conservation plans, identify knowledge gaps and direct future research actions.

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New therapeutics against leishmaniasis are desirable, since the current drugs applied against this disease complex presents problems, such as the toxicity, high cost and/or parasite resistance. In the present study, a new fluoroquinoline derivate, namely 7-chloro-N-(4-fluorophenethyl)quinolin-4-amine or GF1061, was evaluated regarding to its in vitro antileishmanial action against Leishmania infantum and L. amazonensis species, as well as by its toxicity in mammalian cells and efficacy in the treatment of infected macrophages.

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Early developmental stages of fishes are particularly sensitive to changes in environmental variables that affect physiological processes such as metabolism and growth. Both temperature and food availability have significant effects on the growth and survival of larval and juvenile fishes. As climate change and anthropogenic disturbances influence sensitive rearing environments of fishes it is unlikely that they will experience changes in temperature or food availability in isolation.

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Article Synopsis
  • California's coastal ecosystems are facing potential shifts due to climate change, which may harm fish populations essential for recreation and commerce.
  • This study focuses on the impact of CO2-acidification and hypoxia on juvenile rockfish and cabezon, testing their responses at different CO2 and oxygen levels over 1 and 3 weeks.
  • Initial findings show that rockfish experience significant metabolic changes and behavioral shifts after just one week in elevated CO2 and hypoxic conditions, but their responses seem to stabilize over time, suggesting a degree of resilience to these environmental stressors.
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An alternative highly regioselective synthetic method for the preparation of 3,5-disubstituted 4-formyl-N-arylpyrazoles in a one-pot procedure is reported. The methodology developed was based on the regiochemical control of the cyclocondensation reaction of β-enamino diketones with arylhydrazines. Structural modifications in the β-enamino diketone system allied to the Lewis acid carbonyl activator BF were strategically employed for this control.

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Understanding how the current warming trends affect fish populations is crucial for effective conservation and management. To help define suitable thermal habitat for juvenile Chinook salmon, the thermal performance of juvenile Chinook salmon acclimated to either 15 or 19°C was tested across a range of environmentally relevant acute temperature changes (from 12 to 26°C). Swim tunnel respirometers were used to measure routine oxygen uptake as a measure of routine metabolic rate (RMR) and oxygen uptake when swimming maximally as a measure of maximal metabolic rate (MMR) at each test temperature.

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Diversion (i.e. extraction) of water from rivers and estuaries can potentially affect native wildlife populations if operation is not carefully managed.

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Over 3,300 unscreened agricultural water diversion pipes line the levees and riverbanks of the Sacramento River (California) watershed, where the threatened Southern Distinct Population Segment of green sturgeon, Acipenser medirostris, spawn. The number of sturgeon drawn into (entrained) and killed by these pipes is greatly unknown. We examined avoidance behaviors and entrainment susceptibility of juvenile green sturgeon (35±0.

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Water projects designed to extract fresh water for local urban, industrial and agricultural use throughout rivers and estuaries worldwide have contributed to the fragmentation and degradation of suitable habitat for native fishes. The number of water diversions located throughout the Sacramento-San Joaquin watershed in California's Central Valley exceeds 3300, and the majority of these are unscreened. Many anadromous fish species are susceptible to entrainment into these diversions, potentially impacting population numbers.

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Little is known of the swimming capacities of larval sturgeons, despite global population declines in many species due in part to fragmentation of their spawning and rearing habitats by man-made water-diversion structures. Larval green (Acipenser medirostris) and white sturgeon (Acipenser transmontanus) inhabit the highly altered Sacramento-San Joaquin watershed, making them logical species to examine vulnerability to entrainment by altered water flows. The risk of larval sturgeon entrainment is influenced by the ontogeny of swimming capacity and dispersal timing and their interactions with water-diversion structure operations.

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To quantify the salinity preference of juvenile green sturgeon Acipenser medirostris, two groups of A. medirostris [140 days post hatch (dph); total length (L(T) ) 38.0-52.

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This cross-sectional study aimed to estimate the prevalence of hyperuricemia and associated risk factors among Japanese-Brazilians. We obtained data on demographic, health history, food intake, and laboratory variables. Chi-square and prevalence ratios were used as measures of association.

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