Genetic Mapping and Phenotypic Analysis of GstE14 E.4.1 on Eye and Antennae Development in Drosophila melanogaster.

Genetic screens are valuable for identifying novel genes involved in the regulation of developmental processes. To identify genes associated with cell growth regulation in Drosophila melanogaster , a mutagenesis screen was performed. Undergraduate students participating in Fly-CURE phenotypically characterized the E.4.1 mutant which is associated with rough eyes and antennae overgrowth. Following complementation analysis and subsequent genomic sequencing, E.4.1 was identified as a novel mutant allele of GstE14 , a gene involved in ecdysone biosynthesis important for the timing of developmental events. The abnormal eye and antenna phenotypes observed resulting from the loss of GstE14 suggest its role in tissue growth.

Microencapsulation of Gallic Acid Based on a Polymeric and pH-Sensitive Matrix of Pectin/Alginate.

The encapsulation of gallic acid (GA) through several methods has enhanced its shelf life and facilitated industrial applications. Polymeric matrices made of alginate and pectin were evaluated to encapsulate GA via spray drying. The pH-responsive release mechanism was monitored to validate the matrices' performances as wall materials and extend the bioactive compound stability. The microcapsules produced were characterized via scanning electron microscopy (SEM), dynamic light scattering (DLS), Fourier-transform infrared spectroscopy (FTIR), and cyclic voltammetry (CV). The retention and encapsulation efficiency ranges were 45-82% and 79-90%, respectively. The higher values were reached at 3 and 0.75% (w/v) pectin and sodium alginate, respectively. The scanning electron microscopy showed smooth spherical capsules and the average particle size ranged from 1327 to 1591 nm. Their performance and stability were evaluated with optimal results at a pH value of 7 throughout the investigation period. Therefore, this work demonstrated the suitability of gallic acid encapsulation via spray drying using pectin and alginate, which are biopolymers that can be obtained from circular economy processes starting from agro-industrial biomass. The developed formulations provide an alternative to protecting and controlling the release of GA, promoting its application in the food, pharmaceutical, and cosmetic industries and allowing for the release of compounds with high bioactive potential.

Polysaccharides from the Sargassum and Brown Algae Genus: Extraction, Purification, and Their Potential Therapeutic Applications.

Brown macroalgae represent one of the most proliferative groups of living organisms in aquatic environments. Due to their abundance, they often cause problems in aquatic and terrestrial ecosystems, resulting in health problems in humans and the death of various aquatic species. To resolve this, the application of Sargassum has been sought in different research areas, such as food, pharmaceuticals, and cosmetics, since Sargassum is an easy target for study and simple to obtain. In addition, its high content of biocompounds, such as polysaccharides, phenols, and amino acids, among others, has attracted attention. One of the valuable components of brown macroalgae is their polysaccharides, which present interesting bioactivities, such as antiviral, antimicrobial, and antitumoral, among others. There is a wide variety of methods of extraction currently used to obtain these polysaccharides, such as supercritical fluid extraction (SFE), pressurized liquid extraction (PLE), subcritical water extraction (SCWE), ultrasound-assisted extraction (UAE), enzyme-assisted extraction (EAE), and microwave-assisted extraction (MAE). Therefore, this work covers the most current information on the methods of extraction, as well as the purification used to obtain a polysaccharide from Sargassum that is able to be utilized as alginates, fucoidans, and laminarins. In addition, a compilation of bioactivities involving brown algae polysaccharides in in vivo and in vitro studies is also presented, along with challenges in the research and marketing of Sargassum-based products that are commercially available.

Trypanosoma cruzi DTU II coinfection with bacteria producing prolonged cutaneous lesion in a healthy young male.

Chagas disease (CD) is a neglected tropical disease caused by Trypanosoma cruzi and is genetically classified in six discrete typing units (DTUs). The isolates reported in Mexico are generally associated with DTU I. We presented a case of a prolonged cutaneous lesion in a Mexican man, caused by DTU II in coinfection with Bacillus velezensis and Corynebacterium sp. The patient assessment included a complete clinical history, physical exam, laboratory tests, and a skin biopsy. In the facial tissues, intracellular parasites were revealed. The PCR tests were positive for T. cruzi in tissue and blood samples. DNA satellite sequencing was correlated with the DTU II. The initial serological tests reported negative results. However, four months later, two serological tests reported positive results. These exams were performed in different health centers. Mexico is considered an endemic area for CD; nevertheless, this is just the second cutaneous case associated with a DTU different from DTU-I noted in this country. From an ecological point of view, this fact suggests a geographical expansion of DTU II and an association with atypical skin manifestations. Further studies should be conducted to understand this exciting association between DTU-II and prolonged cutaneous expression in humans.

Trypanosoma cruzi DTU II coinfection with bacteria producing prolonged cutaneous lesion in a healthy young male

ABSTRACT Chagas disease (CD) is a neglected tropical disease caused by Trypanosoma cruzi and is genetically classified in six discrete typing units (DTUs). The isolates reported in Mexico are generally associated with DTU I. We presented a case of a prolonged cutaneous lesion in a Mexican man, caused by DTU II in coinfection with Bacillus velezensis and Corynebacterium sp. The patient assessment included a complete clinical history, physical exam, laboratory tests, and a skin biopsy. In the facial tissues, intracellular parasites were revealed. The PCR tests were positive for T. cruzi in tissue and blood samples. DNA satellite sequencing was correlated with the DTU II. The initial serological tests reported negative results. However, four months later, two serological tests reported positive results. These exams were performed in different health centers. Mexico is considered an endemic area for CD; nevertheless, this is just the second cutaneous case associated with a DTU different from DTU-I noted in this country. From an ecological point of view, this fact suggests a geographical expansion of DTU II and an association with atypical skin manifestations. Further studies should be conducted to understand this exciting association between DTU-II and prolonged cutaneous expression in humans.

Lignocellulosic residues as supports for enzyme immobilization, and biocatalysts with potential applications.

Growing demand for agricultural production means a higher quantity of residues produced. The reuse and recycling of agro-industrial wastes reduce worldwide greenhouse emissions. New opportunities are derived from this kind of residuals in the biotechnological field generating valuable products in growing sectors such as transportation, bioenergy, food, and feedstock. The use of natural macromolecules towards biocatalysts offers numerous advantages over free enzymes and friendliness with the environment. Enzyme immobilization improves enzyme properties (stability and reusability), and three types of supports are discussed: inorganic, organic, and hybrid. Several examples of agro-industrial wastes such as coconut wastes, rice husks, corn residues and brewers spent grains (BSG), their properties and potential as supports for enzyme immobilization are described in this work. Before the immobilization, biological and non-biological pretreatments could be performed to enhance the waste potential as a carrier. Additionally, immobilization methods such as covalent binding, adsorption, cross-linking and entrapment are compared to provide high efficiency. Enzymes and biocatalysts for industrial applications offer advantages over traditional chemical processes with respect to sustainability and process efficiency in food, energy, and bioremediation fields. The wastes reviewed in this work demonstrated a high affinity for lipases and laccases and might be used in biodiesel production and textile wastewater treatment, among other applications.

Nanostructures for drug delivery in respiratory diseases therapeutics: Revision of current trends and its comparative analysis.

Respiratory diseases are leading causes of death and disability in developing and developed countries. The burden of acute and chronic respiratory diseases has been rising throughout the world and represents a major problem in the public health system. Acute respiratory diseases include pneumonia, influenza, SARS-CoV-2 and MERS viral infections; while chronic obstructive pulmonary disease (COPD), asthma and, occupational lung diseases (asbestosis, pneumoconiosis) and other parenchymal lung diseases namely lung cancer and tuberculosis are examples of chronic respiratory diseases. Importantly, chronic respiratory diseases are not curable and treatments for acute pathologies are particularly challenging. For that reason, the integration of nanotechnology to existing drugs or for the development of new treatments potentially benefits the therapeutic goals by making drugs more effective and exhibit fewer undesirable side effects to treat these conditions. Moreover, the integration of different nanostructures enables improvement of drug bioavailability, transport and delivery compared to stand-alone drugs in traditional respiratory therapy. Notably, there has been great progress in translating nanotechnology-based cancer therapies and diagnostics into the clinic; however, researchers in recent years have focused on the application of nanostructures in other relevant pulmonary diseases as revealed in our database search. Furthermore, polymeric nanoparticles and micelles are the most studied nanostructures in a wide range of diseases; however, liposomal nanostructures are recognized to be some of the most successful commercial drug delivery systems. In conclusion, this review presents an overview of the recent and relevant research in drug delivery systems for the treatment of different pulmonary diseases and outlines the trends, limitations, importance and application of nanomedicine technology in treatment and diagnosis and future work in this field.

Cutaneous manifestations of COVID-19 in Mexican patients: A case series and review of literature.

China officially recognized atypical pneumonia outbreak in December 2019; on 11 March 2020, the World Health Organization declared COVID-19 as a pandemic that is produced by a new coronavirus, named SARS-CoV-2, of rapid transmissibility, which can be asymptomatic, with mild to severe respiratory symptoms, and with cardiovascular, neurological, gastrointestinal, and cutaneous complications. Considering that the pandemic prolonged more than initially expected was prognostic, it is essential for the medical community to identify the signs and symptoms of COVID-19. Thus, this work's objectives were to present cases of cutaneous lesions observed in COVID-19 Mexican patients. We register cutaneous lesions in COVID-19 patients referred from internal medicine and otorhinolaryngology services to dermatology. We presented four interesting cases with cutaneous lesions, including exanthema morbilliform, urticaria, chilblains, ecchymosis, and facial edema, and review the available literature. The most frequent cutaneous markers are rash, chilblains, and urticaria. Skin lesions may be the first manifestation of COVID-19, accompany initial respiratory symptoms, or appear during the disease course. Symptoms associated with vascular changes (livedo reticularis and vasculitis) are considered of poor prognosis.

Ketamine normalizes high-gamma power in the anterior cingulate cortex in a rat chronic pain model.

Chronic pain alters cortical and subcortical plasticity, causing enhanced sensory and affective responses to peripheral nociceptive inputs. Previous studies have shown that ketamine had the potential to inhibit abnormally amplified affective responses of single neurons by suppressing hyperactivity in the anterior cingulate cortex (ACC). However, the mechanism of this enduring effect has yet to be understood at the network level. In this study, we recorded local field potentials from the ACC of freely moving rats. Animals were injected with complete Freund's adjuvant (CFA) to induce persistent inflammatory pain. Mechanical stimulations were administered to the hind paw before and after CFA administration. We found a significant increase in the high-gamma band (60-100 Hz) power in response to evoked pain after CFA treatment. Ketamine, however, reduced the high-gamma band power in response to evoked pain in CFA-treated rats. In addition, ketamine had a sustained effect on the high-gamma band power lasting up to five days after a single dose administration. These results demonstrate that ketamine has the potential to alter maladaptive neural responses in the ACC induced by chronic pain.

Mapping Cortical Integration of Sensory and Affective Pain Pathways.

Pain is an integrated sensory and affective experience. Cortical mechanisms of sensory and affective integration, however, remain poorly defined. Here, we investigate the projection from the primary somatosensory cortex (S1), which encodes the sensory pain information, to the anterior cingulate cortex (ACC), a key area for processing pain affect, in freely behaving rats. By using a combination of optogenetics, in vivo electrophysiology, and machine learning analysis, we find that a subset of neurons in the ACC receives S1 inputs, and activation of the S1 axon terminals increases the response to noxious stimuli in ACC neurons. Chronic pain enhances this cortico-cortical connection, as manifested by an increased number of ACC neurons that respond to S1 inputs and the magnified contribution of these neurons to the nociceptive response in the ACC. Furthermore, modulation of this S1→ACC projection regulates aversive responses to pain. Our results thus define a cortical circuit that plays a potentially important role in integrating sensory and affective pain signals.

Cortical Pain Processing in the Rat Anterior Cingulate Cortex and Primary Somatosensory Cortex.

Pain is a complex multidimensional experience encompassing sensory-discriminative, affective-motivational and cognitive-emotional components mediated by different neural mechanisms. Investigations of neurophysiological signals from simultaneous recordings of two or more cortical circuits may reveal important circuit mechanisms on cortical pain processing. The anterior cingulate cortex (ACC) and primary somatosensory cortex (S1) represent two most important cortical circuits related to sensory and affective processing of pain. Here, we recorded in vivo extracellular activity of the ACC and S1 simultaneously from male adult Sprague-Dale rats (n = 5), while repetitive noxious laser stimulations were delivered to animalÕs hindpaw during pain experiments. We identified spontaneous pain-like events based on stereotyped pain behaviors in rats. We further conducted systematic analyses of spike and local field potential (LFP) recordings from both ACC and S1 during evoked and spontaneous pain episodes. From LFP recordings, we found stronger phase-amplitude coupling (theta phase vs. gamma amplitude) in the S1 than the ACC (n = 10 sessions), in both evoked (p = 0.058) and spontaneous pain-like behaviors (p = 0.017, paired signed rank test). In addition, pain-modulated ACC and S1 neuronal firing correlated with the amplitude of stimulus-induced event-related potentials (ERPs) during evoked pain episodes. We further designed statistical and machine learning methods to detect pain signals by integrating ACC and S1 ensemble spikes and LFPs. Together, these results reveal differential coding roles between the ACC and S1 in cortical pain processing, as well as point to distinct neural mechanisms between evoked and putative spontaneous pain at both LFP and cellular levels.

A novel neuromodulation strategy to enhance the prefrontal control to treat pain.

Effective pharmacological treatment options for chronic pain remain very limited, and continued reliance on opioid analgesics has contributed to an epidemic in the United States. On the other hand, nonpharmacologic neuromodulatory interventions provide a promising avenue for relief of chronic pain without the complications of dependence and addiction. An especially attractive neuromodulation strategy is to optimize endogenous pain regulatory circuits. The prefrontal cortex is known to provide top-down control of pain, and hence neuromodulation methods that selectively enhance the activities in this brain region during pain episodes have the potential to provide analgesia. In this study, we designed a low-frequency (2 Hz) electrical stimulation protocol to provide temporally and spatially specific enhancement of the prefrontal control of pain in rats. We showed that low-frequency electrical stimulation of the prelimbic region of the prefrontal cortex relieved both sensory and affective responses to acute pain in naive rats. Furthermore, we found that low-frequency electrical stimulation of the prefrontal cortex also attenuated mechanical allodynia in a rat model of chronic pain. Together, our findings demonstrated that low-frequency electrical stimulation of the prefrontal cortex represents a promising new method of neuromodulation to inhibit pain.

Intracranial Pharmacotherapy and Pain Assays in Rodents.

Pain is a salient sensory experience with affective and cognitive dimensions. However, central mechanisms for pain remain poorly understood, hindering the development of effective therapeutics. Intracranial pharmacology presents an important tool for understanding the molecular and cellular mechanisms of pain in the brain, as well as for novel treatments. Here we present a protocol that integrates intracranial pharmacology with pain behavior testing. Specifically, we show how to infuse analgesic drugs into a select brain region, which may be responsible for pain modulation. Furthermore, to determine the effect of the candidate drug in the central nerve system, pain assays are performed after intracranial treatment. Our results demonstrate that intracranial administration of analgesic drugs in a targeted region can provide relief of pain in rodents. Thus, our protocol successfully demonstrates that intracranial pharmacology, combined with pain behavior testing, can be a powerful tool for the study of pain mechanisms in the brain.

Effects of a single subanaesthetic dose of ketamine on pain and mood after laparoscopic bariatric surgery: A randomised double-blind placebo controlled study.

BACKGROUND: When administered as a continuous infusion, ketamine is known to be a potent analgesic and general anaesthetic. Recent studies suggest that a single low-dose administration of ketamine can provide a long-lasting effect on mood, but its effects when given in the postoperative period have not been studied. OBJECTIVE: We hypothesised that a single low-dose administration of ketamine after bariatric surgery can improve pain and mood scores in the immediate postoperative period. DESIGN: We performed a randomised, double-blind, placebo-controlled study to compare a single subanaesthetic dose of ketamine (0.4 mg kg) with a normal saline placebo in the postanaesthesia care unit after laparoscopic gastric bypass and gastrectomy. SETTING: Single-centre, tertiary care hospital, October 2014 to January 2018. PATIENTS: A total of 100 patients were randomised into the ketamine and saline groups. INTERVENTION: Patients in the ketamine group received a single dose of ketamine infusion (0.4 mg kg) in the postanaesthesia care unit. Patients in the placebo groups received 0.9% saline. OUTCOME MEASURES: The primary outcome was the visual analogue pain score. A secondary outcome was performance on the short-form McGill's Pain Questionnaire (SF-MPQ). RESULTS: There were no significant differences in visual analogue pain scores between groups (group-by-time interaction P = 0.966; marginal group effect P = 0.137). However, scores on the affective scale of SF-MPQ (secondary outcome) significantly decreased in the ketamine group as early as postoperative day (POD) 2 [mean difference = -2.2 (95% bootstrap CI -2.9 to 1.6), Bonferroni adjusted P < 0.001], compared with placebo group in which the scores decreased only by POD 7. Scores on the total scale of SF-MPQ for the ketamine group were smaller compared with the placebo group (P = 0.034). CONCLUSION: Although there was no significant difference between ketamine and placebo for the primary outcome measure, patients who received ketamine experienced statistically and clinically significant improvement in their comprehensive evaluation of pain, particularly the affective component of pain, on POD 2. However, future studies are needed to confirm the enduring effects of ketamine on the affective response to postoperative pain. CLINICAL TRIAL REGISTRATION: NCT02452060. : This article is accompanied by the following Invited Commentaries:Mion G. Ketamine stakes in 2018. Right doses, good choices. Eur J Anaesthesiol 2019; 36:1-3.Robu B, Lavand'homme, P. Targeting the affective component of pain with ketamine. A tool to improve the postoperative experience? Eur J Anaesthesiol 2019; 36:4-5.

Ketamine reduces aversion in rodent pain models by suppressing hyperactivity of the anterior cingulate cortex.

Chronic pain is known to induce an amplified aversive reaction to peripheral nociceptive inputs. This enhanced affective response constitutes a key pathologic feature of chronic pain syndromes such as fibromyalgia. However, the neural mechanisms that underlie this important aspect of pain processing remain poorly understood, hindering the development of treatments. Here, we show that a single dose of ketamine can produce a persistent reduction in the aversive response to noxious stimuli in rodent chronic pain models, long after the termination of its anti-nociceptive effects. Furthermore, we demonstrated that this anti-aversive property is mediated by prolonged suppression of the hyperactivity of neurons in the anterior cingulate cortex (ACC), a brain region well known to regulate pain affect. Therefore, our results indicate that it is feasible to dissociate the affective from the sensory component of pain, and demonstrate the potential for low-dose ketamine to be an important therapy for chronic pain syndromes.

Inhibition of the Prefrontal Projection to the Nucleus Accumbens Enhances Pain Sensitivity and Affect.

Cortical mechanisms that regulate acute or chronic pain remain poorly understood. The prefrontal cortex (PFC) exerts crucial control of sensory and affective behaviors. Recent studies show that activation of the projections from the PFC to the nucleus accumbens (NAc), an important pathway in the brain's reward circuitry, can produce inhibition of both sensory and affective components of pain. However, it is unclear whether this circuit is endogenously engaged in pain regulation. To answer this question, we disrupted this circuit using an optogenetic strategy. We expressed halorhodopsin in pyramidal neurons from the PFC, and then selectively inhibited the axonal projection from these neurons to neurons in the NAc core. Our results reveal that inhibition of the PFC or its projection to the NAc, heightens both sensory and affective symptoms of acute pain in naïve rats. Inhibition of this corticostriatal pathway also increased nociceptive sensitivity and the aversive response in a chronic neuropathic pain model. Finally, corticostriatal inhibition resulted in a similar aversive phenotype as chronic pain. These results strongly suggest that the projection from the PFC to the NAc plays an important role in endogenous pain regulation, and its impairment contributes to the pathology of chronic pain.

Local field potential decoding of the onset and intensity of acute pain in rats.

Pain is a complex sensory and affective experience. The current definition for pain relies on verbal reports in clinical settings and behavioral assays in animal models. These definitions can be subjective and do not take into consideration signals in the neural system. Local field potentials (LFPs) represent summed electrical currents from multiple neurons in a defined brain area. Although single neuronal spike activity has been shown to modulate the acute pain, it is not yet clear how ensemble activities in the form of LFPs can be used to decode the precise timing and intensity of pain. The anterior cingulate cortex (ACC) is known to play a role in the affective-aversive component of pain in human and animal studies. Few studies, however, have examined how neural activities in the ACC can be used to interpret or predict acute noxious inputs. Here, we recorded in vivo extracellular activity in the ACC from freely behaving rats after stimulus with non-noxious, low-intensity noxious, and high-intensity noxious stimuli, both in the absence and chronic pain. Using a supervised machine learning classifier with selected LFP features, we predicted the intensity and the onset of acute nociceptive signals with high degree of precision. These results suggest the potential to use LFPs to decode acute pain.

Scaling Up Cortical Control Inhibits Pain.

Acute pain evokes protective neural and behavioral responses. Chronic pain, however, disrupts normal nociceptive processing. The prefrontal cortex (PFC) is known to exert top-down regulation of sensory inputs; unfortunately, how individual PFC neurons respond to an acute pain signal is not well characterized. We found that neurons in the prelimbic region of the PFC increased firing rates of the neurons after noxious stimulations in free-moving rats. Chronic pain, however, suppressed both basal spontaneous and pain-evoked firing rates. Furthermore, we identified a linear correlation between basal and evoked firing rates of PFC neurons, whereby a decrease in basal firing leads to a nearly 2-fold reduction in pain-evoked response in chronic pain states. In contrast, enhancing basal PFC activity with low-frequency optogenetic stimulation scaled up prefrontal outputs to inhibit pain. These results demonstrate a cortical gain control system for nociceptive regulation and establish scaling up prefrontal outputs as an effective neuromodulation strategy to inhibit pain.

Assessment of Aversion of Acute Pain Stimulus through Conditioned Place Aversion.

Pain is a complex experience. The aversive component of pain has been assessed through conditioned place aversion in rodents. However, this behavioral test does not allow the evaluation of the aversion of an acute pain stimulus. In Zhang et al. (2017), we provide an updated version of a Conditioned Place Aversion paradigm to address this challenge. In this protocol, a detailed version of this method is described.

AMPAkines and morphine provide complementary analgesia.

Glutamate signaling in the central nervous system is known to play a key role in pain regulation. AMPAkines can enhance glutamate signaling through α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors. previous studies have shown that AMPAkines are effective analgesic agents, and their site of action is likely in the brain. It is not known, however, if AMPAkines can provide complementary analgesia in combination with opioids, the most commonly used analgesics. Here, we show that the co-administration of an AMPAkine with morphine can provide additional analgesia, both in naïve rats and in rats that experience postoperative pain. Furthermore, we show that this AMPAkine can be administered directly into the prefrontal cortex to provide analgesia, and that prefrontal AMPAkine infusion, similar to systemic administration, can provide added pain relief to complement morphine analgesia.