Mefenoxam and pyraclostrobin: toxicity and in vitro inhibitory activity against Pythium insidiosum.

The objective of this study is to verify in vitro susceptibility of Pythium insidiosum against the agricultural fungicides mefenoxam and pyraclostrobin and evaluate the toxicity of both compounds. Twenty-one P. insidiosum isolates were tested against mefenoxam and pyraclostrobin using the broth microdilution method. Minimum inhibitory and oomicidal concentrations for both compounds were established. Additionally, scanning electron microscopy was performed on P. insidiosum hyphae treated with the sublethal concentration of each fungicide. The toxicity of the compounds was evaluated in vivo Caenorhabditis elegans model. The concentration to inhibit 100% of P. insidiosum growth ranged from 0·625 to 10 µg ml-1 for mefenoxam and from 0·019 to 5 µg ml-1 for pyraclostrobin. The SEM analysis revealed changes on the surface of the hyphae treated with the fungicides, suggesting possible damage caused by these compounds. There was no evidence of toxicity in vivo models. Mefenoxam and pyraclostrobin did not show toxicity at the doses evaluated and have inhibitory effects on the pathogenic oomycete P. insidiosum. However, further evaluations of their pharmacokinetics and toxicity in different animal species and possible pharmacological interactions are necessary to infer a possible use in the clinical management of pythiosis.

Corticosteroids and tocilizumab reduce in-hospital mortality in severe COVID-19 pneumonia: a retrospective study in a Spanish hospital.

BACKGROUND: There is an urgent need to reduce mortality of COVID-19. We examined if corticosteroids and tocilizumab reduce risk for death in patients with severe pneumonia caused by SARS-CoV-2. METHODS: A retrospective cohort study was performed in a single university hospital. All adult patients admitted with confirmed severe COVID-19 pneumonia from 9 March to 9 April 2020 were included. Severe pneumonia was defined as multi-lobar or bilateral pneumonia and a ratio of oxygen saturation by pulse oximetry to the fraction of inspired oxygen (SpFi)<315. All patients received antiviral and antibiotic treatment. From March 26, patients also received immunomodulatory treatment with corticosteroids (methylprednisolone 250 mg/day for 3 days), or tocilizumab or both. In-hospital mortality in the entire cohort and in a 1:1 matched cohort sub-analysis was evaluated. RESULTS: 255 patients were included, 118 received only antiviral and antibiotic treatment while 137, admitted after March 26, also received immunomodulators. In-hospital mortality of patients on immunomodulatory treatment was significantly lower than in those without [47/137(34.3%) vs. 69/118(58.5%), (p < .001)]. The risk of death was 0.44 (CI, 0.26-0.76) in patients receiving corticosteroids alone and 0.292 (CI, 0.18-0.47) in those treated with corticosteroids and tocilizumab. In the sub-analysis with 202 matched patients, the risk of death was 0.356 (CI 0.179-0.707) in patients receiving corticosteroids alone and 0.233 (0.124-0.436) in those treated with the combination. CONCLUSIONS: Combined treatment with corticosteroids and tocilizumab reduced mortality with about 25% in patients with severe COVID-19 pneumonia. Corticosteroids alone also resulted in lower in-hospital mortality rate compared to patients receiving only antiviral and antibiotic treatment. Corticosteroids alone or combined with tocilizumab may be considered in patients with severe COVID-19 pneumonia.

New software dedicated to virtual mazes for human cognitive investigations.

BACKGROUND: Compared to previous neuropsychological investigations with standard paper-pen tests limited to test complex spatial learning and memory processes, 3-D virtual immersive technology might offer new tools for research purposes and for diagnosis in patients suffering from mild cognitive impairment or dementia. COMPARISON WITH EXISTING METHODS: Current software proposes a customizable VR environment combined with an analyser module based on regions of interest and some parameters of analysis or pre-calibrated VR mazes with raw data. NEW METHOD: We attempted to create the VRmaze software offering either turnkey mazes with automatic tracking and analysis, or more complex and specific virtual mazes for human brain-behavioural research adaptable to all desired settings and parameters of analysis. The software combines 3D pre-calibrated VR tests or free customizable VR tests with digitized neuropsychological 2D standard and validated tests or tasks. RESULTS: We have tested an ERAM, a MWM and a reverse T-maze on 44 healthy subjects, showing gender differences in terms of navigation strategy. We have observed that the choice of benchmarks, instructions, and experimental parameters influence the performances. CONCLUSION: VRmaze software offers a translational approach for research units that wish to combine animal models and patient evaluations as well as complex 3D tasks and standardized neuropsychological tests combined with an automatic analysis opening a large perspective in the neurosciences to investigate cognitive functions. A clinical module with preconfigured 2- and 3-D tasks should offer clinicians an easy way to evaluate their patients routinely.

The critical role of vestibular graviception during cognitive-motor development.

Earth's gravity acts both as a mechanical stimulus on the body and as a sensory stimulus to the vestibular organ, which is transmitted into the brain. The vestibular system has been recently highlighted as the cornerstone of the multisensory cortex and of the dorsal hippocampus related to spatial cognition. Consequently, we have hypothesized that the vestibular sensory perception of gravity by the otoliths might also play a crucial role during the first stages of development in both sensorimotor and cognitive functions and the construction and perception of the 'self' and related functions of orientation and navigation. We have investigated an original mouse model (Head Tilted mice, B6Ei.GL-Nox3het/J) suffering from a selective congenital absence of vestibular otolithic gravisensors. We report that mouse pups suffered from a delay in the acquisition of sensorimotor reflexes, spatial olfactory guidance, path integration, and ultrasonic communication, while maternal care remained normal. We demonstrate that development has a critical period dependent on the vestibular otolithic sensory perception of gravity, probably temporally between the somesthetic and visual critical periods. The symptoms expressed by the congenital otolithic-deficient mice are similar to validated mouse models of autism and highlight the significance of vestibular graviception in the pathophysiology of development.

Mechanisms involved in anti-aging effects of guarana (Paullinia cupana) in Caenorhabditis elegans.

Guarana (Paullinia cupana) is habitually ingested by people in the Amazon region and is a key ingredient in various energy drinks consumed worldwide. Extension in longevity and low prevalence of chronic age-related diseases have been associated to habitual intake of guarana. Anti-aging potential of guarana was also demonstrated in Caenorhabditis elegans; however, the mechanisms involved in its effects are not clear. Herein, we investigated the putative pathways that regulate the effects of guarana ethanolic extract (GEE) on lifespan using C. elegans. The major known longevity pathways were analyzed through mutant worms and RT-qPCR assay (DAF-2, DAF-16, SKN-1, SIR-2.1, HSF-1). The possible involvement of purinergic signaling was also investigated. This study demonstrated that GEE acts through antioxidant activity, DAF-16, HSF-1, and SKN-1 pathways, and human adenosine receptor ortholog (ADOR-1) to extend lifespan. GEE also downregulated skn-1, daf-16, sir-2.1 and hsp-16.2 in 9-day-old C. elegans, which might reflect less need to activate these protective genes due to direct antioxidant effects. Our results contribute to the comprehension of guarana effects in vivo, which might be helpful to prevent or treat aging-associated disorders, and also suggest purinergic signaling as a plausible therapeutic target for longevity studies.

Mechanisms involved in anti-aging effects of guarana (Paullinia cupana) in Caenorhabditis elegans

Guarana (Paullinia cupana) is habitually ingested by people in the Amazon region and is a key ingredient in various energy drinks consumed worldwide. Extension in longevity and low prevalence of chronic age-related diseases have been associated to habitual intake of guarana. Anti-aging potential of guarana was also demonstrated in Caenorhabditis elegans; however, the mechanisms involved in its effects are not clear. Herein, we investigated the putative pathways that regulate the effects of guarana ethanolic extract (GEE) on lifespan using C. elegans. The major known longevity pathways were analyzed through mutant worms and RT-qPCR assay (DAF-2, DAF-16, SKN-1, SIR-2.1, HSF-1). The possible involvement of purinergic signaling was also investigated. This study demonstrated that GEE acts through antioxidant activity, DAF-16, HSF-1, and SKN-1 pathways, and human adenosine receptor ortholog (ADOR-1) to extend lifespan. GEE also downregulated skn-1, daf-16, sir-2.1 and hsp-16.2 in 9-day-old C. elegans, which might reflect less need to activate these protective genes due to direct antioxidant effects. Our results contribute to the comprehension of guarana effects in vivo, which might be helpful to prevent or treat aging-associated disorders, and also suggest purinergic signaling as a plausible therapeutic target for longevity studies.

Rosmarinus officinalis L. increases Caenorhabditis elegans stress resistance and longevity in a DAF-16, HSF-1 and SKN-1-dependent manner.

Improving overall health and quality of life, preventing diseases and increasing life expectancy are key concerns in the field of public health. The search for antioxidants that can inhibit oxidative damage in cells has received a lot of attention. Rosmarinus officinalis L. represents an exceptionally rich source of bioactive compounds with pharmacological properties. In the present study, we explored the effects of the ethanolic extract of R. officinalis (eeRo) on stress resistance and longevity using the non-parasitic nematode Caenorhabditis elegans as a model. We report for the first time that eeRo increased resistance against oxidative and thermal stress and extended C. elegans longevity in an insulin/IGF signaling pathway-dependent manner. These data emphasize the eeRo beneficial effects on C. elegans under stress.

Rosmarinus officinalis L. increases Caenorhabditis elegans stress resistance and longevity in a DAF-16, HSF-1 and SKN-1-dependent manner

Improving overall health and quality of life, preventing diseases and increasing life expectancy are key concerns in the field of public health. The search for antioxidants that can inhibit oxidative damage in cells has received a lot of attention. Rosmarinus officinalis L. represents an exceptionally rich source of bioactive compounds with pharmacological properties. In the present study, we explored the effects of the ethanolic extract of R. officinalis (eeRo) on stress resistance and longevity using the non-parasitic nematode Caenorhabditis elegans as a model. We report for the first time that eeRo increased resistance against oxidative and thermal stress and extended C. elegans longevity in an insulin/IGF signaling pathway-dependent manner. These data emphasize the eeRo beneficial effects on C. elegans under stress.

Safety and effectiveness of home intravenous antibiotic therapy for multidrug-resistant bacterial infections.

Home intravenous antibiotic therapy is an alternative to hospital admission for moderately severe infections. However, few studies have analyzed its safety and effectiveness in the treatment of infections caused by multidrug-resistant bacteria. The purpose of this study is to analyze the safety and effectiveness of home intravenous antibiotic therapy in multidrug-resistant bacterial infections. We analyzed prospectively all patients admitted to our service who underwent home intravenous antibiotic therapy during the period 2008-2012. All the treatments were administered by caretakers or self-administered by patients, through elastomeric infusion devices. Effectiveness was evaluated by analyzing the readmission rate for poor infection control. Safety was evaluated by analyzing adverse events, catheter-related complications, and readmissions not related to poor infection control. There were 433 admissions (in 355 patients) for home intravenous antibiotic therapy during the study period. There were 226 (52.2 %) admissions due to multidrug-resistant bacterial infections and 207 (47.8 %) due to non-multidrug-resistant infections. Hospital readmissions in patients with multidrug-resistant infections were uncommon. Multidrug-resistant enterococcal infections, healthcare-associated infections, and carbapenem therapy were independent variables associated with increased readmissions due to poor infection control. Readmissions not related to poor infection control, adverse events, and catheter-related complications were similar in multidrug-resistant compared to non-multidrug-resistant bacterial infections. Home intravenous therapy, administered by patients or their caretakers using elastomeric infusion pumps, was safe and effective for the treatment of most multidrug-resistant bacterial infections.

Diphenyl-diselenide suppresses amyloid-ß peptide in Caenorhabditis elegans model of Alzheimer's disease.

Alzheimer's disease (AD) is the most common and devastating neurodegenerative disease. The etiology of AD has yet to be fully understood, and common treatments remain largely non-efficacious. The amyloid hypothesis posits that extracellular amyloid-ß (Aß) deposits are the fundamental etiological factor of the disease. The present study tested the organoselenium compound diphenyl-diselenide (PhSe)2, which is characterized by its antioxidant and antiinflammatory properties and has shown efficacy in several neurodegenerative disease models. We employed a transgenic Caenorhabditis elegans AD model to analyze the effects of (PhSe)2 treatment on Aß peptide-induced toxicity. Chronic exposure to (PhSe)2 attenuated oxidative stress induced by Aß1-42, with concomitant recovery of associative learning memory in C. elegans. Additionally, (PhSe)2 decreased Aß1-42 transgene expression, suppressed Aß1-42 peptide, and downregulated hsp-16.2 by reducing the need for this chaperone under Aß1-42-induced toxicity. These observations suggest that (PhSe)2 plays an important role in protecting against oxidative stress-induced toxicity, thus representing a promising pharmaceutical modality that attenuates Aß1-42 expression.

Effect of a Pulmonary Rehabilitation Program on the levels of anxiety and depression and on the quality of life of patients with chronic obstructive pulmonary disease.

OBJECTIVE: To analyze the effect of a Pulmonary Rehabilitation Program (PRP) on the levels of anxiety and depression and the quality of life of patients with chronic obstructive pulmonary disease. METHOD: Patients with chronic obstructive pulmonary disease (COPD) who completed the PRP of 3 weekly sessions of 60 min duration for 12 weeks, a total of 36 sessions, were assessed using Beck Inventory (BAI and BDI) and Saint George's Respiratory Questionnaire (SGRQ). RESULTS: A total of 125 individuals, with an average age of 63.7 ± 8.8 years, FEV1: 1.17 ± 0.57L (43.18 ± 18.79% predicted), 61.6% male and 38.4% female, were analyzed. The BAI and BDI before and after PRP were, respectively, 10.15 ± 6.32 vs. 7.67 ± 7.21; p=0.0041 and 12.60 ± 7.99 vs. 8.96 ± 7.29; p=0.00016. The results of the SGRQ domains were, respectively, Before and After symptoms (48.53 ± 20.41 vs. 32.58 ± 18.95), Activity (69.15 ± 20.79 vs. 52.42 ± 23.70), Impact (32.92 ± 18.29 vs. 20.27 ± 16.70), Total (46.69 ± 16.90 vs. 32.07 ± 16.96). When correlating the BDI to the domains of the SGRQ, weak correlations were observed (Symptoms r=0.22; p=0.01; Activity r=0.28; p=0.001; Impact r=0.52; p=2.72; Total r=0.44; p=0.17). In the same way, weak correlations were observed when correlating the BAI to the SGRQ (Symptoms r=0.28; p=0.0009; Activity r=0.32; p=0.0005; Impact r=0.42; p=7.33; Total r=0.43; p=0.74). CONCLUSION: Although the PRP improves levels of depression and anxiety as well as the quality of life in patients with COPD, no significant correlation of these analyzed variables was observed.

Characterization of isolates of Acanthamoeba from the nasal mucosa and cutaneous lesions of dogs.

Acanthamoeba spp. are free-living amoebae that are ubiquitously distributed in the environment and can cause encephalomyelitis in animals and humans. The factors that contribute to Acanthamoeba infections include parasite biology, genetic diversity, environmental spread, and host susceptibility. The aim of the present study was to characterize isolates of Acanthamoeba from the nasal mucosa and cutaneous lesions of dogs in order to access the occurence and pathogenicity of these organisms in this animal group. We studied 13 isolates of Acanthamoeba confirmed by polymerase chain reaction. They were sequenced, the genotype was determined, and their potential of pathogenicity was evaluated.

Spatial and non-spatial performance in mutant mice devoid of otoliths.

Vestibular deafferentation induces strong spatial memory impairments in rodents and dorsal hippocampal atrophy in humans, suggesting that vestibular information plays an important role in spatial-memory processes. However, previous studies have not discriminated between the role of the semi-circular canals, gravisensors and cochlear sense organ in such impairments due to complete damage of the vestibular and cochlear organs in their models of lesions. This is the first time that mutant mice (het/het) devoid of otoconia (lack of vestibular gravisensors) have been evaluated in behavioral tests. Results show different levels of achievement in the tests. The rotarod and elevated plus-maze were not executable, the rotarod being a safer test for differentiating the het/het mouse phenotype compared to the more anxiogenic swimming pool. Y-maze and place recognition tests were achieved, but chance values were not reached in the het/het group. Additionally, het/het mice presented uncommon behavior when faced with objects during the object recognition test. Impairments in het/het mice in the Y-maze test suggest a crucial role of the vestibular gravisensors in spatial-memory processes.

Influence of anxiety in spatial memory impairments related to the loss of vestibular function in rat.

It is now well established that vestibular information plays an important role in spatial memory processes. Although vestibular lesions induce anxiety in humans, this finding remains controversial in rodents. However, it is possible that anxiety-related behavior is associated with spatial memory impairments after vestibular lesions. We aimed to evaluate anxiety-like behavior and the effect of an anxiolytic treatment during a complex spatial memory task in a rat model of compensated bilateral vestibular lesions. Adult rats were divided into four groups, with or without vestibular lesions and, treated or untreated by diazepam. The vestibular lesion was performed by transtympanic injection of arsanilate and compared to transtympanic saline injection. Diazepam or saline was administered 1h before each test or learning session. Vestibular-lesioned rats exhibited anxiety-like behavior which was decreased with diazepam. Spatial memory performance was similar in control-treated and untreated groups, suggesting no effect on memory at the dose of diazepam used. Spatial memory performances were not modified by anxiolytic drug treatment in vestibular-lesioned rats compared to vestibular-lesioned rats without drug treatment. We conclude that bilateral vestibular lesions in rats induced anxiety-like behavior which was unrelated to spatial memory impairment and was probably specifically related to the loss of vestibular information.

Influence of vestibular input on spatial and nonspatial memory and on hippocampal NMDA receptors.

It has recently been shown that a lack of vestibular sensory information decreases spatial memory performance and induces biochemical changes in the hippocampus in rodents. After vestibular neurectomy, patients display spatial memory deficit and hippocampal atrophy. Our objectives were to explore: (a) spatial (Y maze, radial-arm maze), and non-spatial (object recognition) memory performance, (b) modulation of NMDA receptors within the hippocampus using radioligand binding, and (c) hippocampal atrophy, using MRI, in a rat model of bilateral labyrinthectomy realized in two operations. Chemical vestibular lesions (VLs) were induced in 24 animals by transtympanic injections of sodium arsanilate (30 mg/0.1 ml/ear), one side being lesioned 3 weeks after the other. The control group received transtympanic saline solution (0.1 ml/ear) (n = 24). Spatial memory performance (Y maze and radial maze) decreased after VL. Conversely, non-spatial memory performance (object recognition) was not affected by VL. No hippocampal atrophy was observed with MRI, but density of NMDA receptors were increased in the hippocampus after VL. These findings show that the lack of vestibular information induced specific deficits in spatial memory. Additionally, quantitative autoradiographic data suggest the involvement of the glutamatergic system in spatial memory processes related to vestibular information. When studying spatial memory performances in the presence of vestibular syndrome, two-step labyrinthectomy is a suitable procedure for distinguishing between the roles of the specific components of vestibular input loss and those of impaired locomotor activity.

Evaluation of the chemical model of vestibular lesions induced by arsanilate in rats.

Several animal models of vestibular deficits that mimic the human pathology phenotype have previously been developed to correlate the degree of vestibular injury to cognate vestibular deficits in a time-dependent manner. Sodium arsanilate is one of the most commonly used substances for chemical vestibular lesioning, but it is not well described in the literature. In the present study, we used histological and functional approaches to conduct a detailed exploration of the model of vestibular lesions induced by transtympanic injection of sodium arsanilate in rats. The arsanilate-induced damage was restricted to the vestibular sensory organs without affecting the external ear, the oropharynx, or Scarpa's ganglion. This finding strongly supports the absence of diffusion of arsanilate into the external ear or Eustachian tubes, or through the eighth cranial nerve sheath leading to the brainstem. One of the striking observations of the present study is the complete restructuring of the sensory epithelia into a non sensory epithelial monolayer observed at 3months after arsanilate application. This atrophy resembles the monolayer epithelia observed postmortem in the vestibular epithelia of patients with a history of lesioned vestibular deficits such as labyrinthectomy, antibiotic treatment, vestibular neuritis, or Ménière's disease. In cases of Ménière's disease, aminoglycosides, and platinum-based chemotherapy, vestibular hair cells are destroyed, regardless of the physiopathological process, as reproduced with the arsanilate model of vestibular lesion. These observations, together with those presented in this study of arsanilate vestibular toxicity, suggest that this atrophy process relies on a common mechanism of degeneration of the sensory epithelia.

In vitro susceptibility of fluconazole-susceptible and -resistant isolates of Malassezia pachydermatis against azoles.

OBJECTIVES: The first aim of this study was to evaluate the in vitro efficacies of fluconazole, ketoconazole, itraconazole and voriconazole on M. pachydermatis growth inhibition. This study also evaluated M. pachydermatis azole cross-resistance, comparing wild clinical isolates and the same isolates with in vitro-induced fluconazole resistance. METHODS: Two techniques were used: (1) a broth microdilution method based on protocol M27-A3 from the Clinical and Laboratory Standards Institute to determine the minimum inhibitory concentration (MIC) and (2) the Fekete-Forgács method to induce fluconazole resistance in vitro. The isolates were divided into two groups: group 1 included fluconazole-susceptible clinical isolates (n=30) and group 2 contained the same isolates with in vitro-induced fluconazole resistance (n=30). RESULTS: The two groups exhibited differences in susceptibility (p<0.001). Group 1 isolates were susceptible to azoles: ketoconazole (MIC 0.01-1.0 µg/mL), itraconazole (MIC 0.01-1.0 µg/mL), voriconazole (MIC 0.01-4.0 µg/mL), and fluconazole (MIC 0.01-4.0 µg/mL). Group 2 isolates demonstrated a wider range of MICs to azoles: ITZ (MIC 0.06-64.0 µg/mL), KTZ (MIC 0.25-32.0 µg/mL), VRZ (MIC 2.0-128.0 µg/mL), and FLZ (MIC 64.0-128.0 µg/mL). CONCLUSIONS: It was shown that FLZ-resistant M. pachydermatis isolates exhibit cross-resistance to other azoles, reinforcing the importance of susceptibility tests as a guide for the therapeutic prescription of antifungals in medical and veterinary mycology.

Physiological and molecular characterization of atypical lipid-dependent Malassezia yeasts from a dog with skin lesions: adaptation to a new host?

Three lipid-dependent Malassezia isolates (here named 114A, 114B and 114C) recovered from a dog with skin lesions were phenotypically and genotypically characterized. All presented ovoid cells and buds formed on a narrow base. Most of the results from physiological tests were consistent with those of Malassezia furfur. The phylogenetic analysis of ITS-1 and LSU nucleotide sequences was concordant in placing all three clinical Malassezia isolates close to M. furfur. However, the phylogenetic data on the chs-2 sequence revealed that clinical isolate 114A is distinct from M. furfur and was closely affiliated to the sequence of M. pachydermatis with high nodal support. In particular, lipid-dependent isolates 114A displayed chs-2 sequences similar (100%) to that of the non-lipid dependent species Malassezia pachydermatis. The presence of the genetic and physiological polymorphisms detected in these three isolates of M. furfur could have resulted from a process of adaptation of this anthropophilic species to a new host.

Analysis of kinematics of the lower limb during step exercise.

The motion of lower extremity joints is one of the mechanisms by which mechanical load is attenuated. The main purposes of this study were to characterize the motion of the right lower limb in a group of 18 women experienced in step exercise, when performing selected step patterns, and to investigate the differences that exist between four stepping rate conditions (125, 130, 135, and 140 beats per minute) and between four step patterns (basic step, knee lift, run step, and knee hop). The parameters explored were the range-of-movement and angular velocity of hip, knee, and ankle joints at initial contact and peak values. The four movement patterns analyzed presented different kinematical profiles, but no profiles were influenced by stepping rate. Stepping rate and step pattern had more effect on range of motion of ankle and knee joints, and on the angular velocity of knee and hip joints. To prevent injury, proper instruction should be provided in relation to foot placement on the step bench and on the ground.