An in vitro-in silico workflow for predicting renal clearance of PFAS.

Per- and poly-fluoroalkyl substances (PFAS) have a wide range of elimination half-lives (days to years) in humans, thought to be in part due to variation in proximal tubule reabsorption. While human biomonitoring studies provide important data for some PFAS, renal clearance (CLrenal) predictions for hundreds of PFAS in commerce requires experimental studies with in vitro models and physiologically-based in vitro-to-in vivo extrapolation (IVIVE). Options for studying renal proximal tubule pharmacokinetics include cultures of renal proximal tubule epithelial cells (RPTECs) and/or microphysiological systems. This study aimed to compare CLrenal predictions for PFAS using in vitro models of varying complexity (96-well plates, static 24-well Transwells and a fluidic microphysiological model, all using human telomerase reverse transcriptase-immortalized and OAT1-overexpressing RPTECs combined with in silico physiologically-based IVIVE. Three PFAS were tested: one with a long half-life (PFOS) and two with shorter half-lives (PFHxA and PFBS). PFAS were added either individually (5 µM) or as a mixture (2 µM of each substance) for 48 h. Bayesian methods were used to fit concentrations measured in media and cells to a three-compartmental model to obtain the in vitro permeability rates, which were then used as inputs for a physiologically-based IVIVE model to estimate in vivo CLrenal. Our predictions for human CLrenal of PFAS were highly concordant with available values from in vivo human studies. The relative values of CLrenal between slow- and faster-clearance PFAS were most highly concordant between predictions from 2D culture and corresponding in vivo values. However, the predictions from the more complex model (with or without flow) exhibited greater concordance with absolute CLrenal. Overall, we conclude that a combined in vitro-in silico workflow can predict absolute CLrenal values, and effectively distinguish between PFAS with slow and faster clearance, thereby allowing prioritization of PFAS with a greater potential for bioaccumulation in humans.

ADME characterization and PBK model development of 3 highly protein-bound UV filters through topical application.

Estimating human exposure in the safety assessment of chemicals is crucial. Physiologically based kinetic (PBK) models which combine information on exposure, physiology, and chemical properties, describing the absorption, distribution, metabolism, and excretion (ADME) processes of a chemical, can be used to calculate internal exposure metrics such as maximum concentration and area under the concentration-time curve in plasma or tissues of a test chemical in next-generation risk assessment. This article demonstrates the development of PBK models for 3 UV filters, specifically octyl methoxycinnamate, octocrylene, and 4-methylbenzylidene camphor. The models were parameterized entirely based on data obtained from in vitro and/or in silico methods in a bottom-up modeling approach and then validated based on human dermal pharmacokinetic (PK) data. The 3 UV filters are "difficult to test" in in vitro test systems due to high lipophilicity, high binding affinity for proteins, and nonspecific binding, for example, toward plastic. This research work presents critical considerations in ADME data generation, interpretation, and parameterization to assure valid PBK model development to increase confidence in using PBK modeling to help make safety decisions in the absence of human PK data. The developed PBK models of the 3 chemicals successfully simulated the plasma concentration profiles of clinical PK data following dermal application, indicating the reliability of the ADME data generated and the parameters determined. The study also provides insights and lessons learned for characterizing ADME and developing PBK models for highly lipophilic and protein-bound chemicals in the future.

Analysis of reproducibility and robustness of a renal proximal tubule microphysiological system OrganoPlate 3-lane 40 for in vitro studies of drug transport and toxicity.

Microphysiological systems are an emerging area of in vitro drug development, and their independent evaluation is important for wide adoption and use. The primary goal of this study was to test reproducibility and robustness of a renal proximal tubule microphysiological system, OrganoPlate 3-lane 40, as an in vitro model for drug transport and toxicity studies. This microfluidic model was compared with static multiwell cultures and tested using several human renal proximal tubule epithelial cell (RPTEC) types. The model was characterized in terms of the functional transport for various tubule-specific proteins, epithelial permeability of small molecules (cisplatin, tenofovir, and perfluorooctanoic acid) versus large molecules (fluorescent dextrans, 60-150 kDa), and gene expression response to a nephrotoxic xenobiotic. The advantages offered by OrganoPlate 3-lane 40 as compared with multiwell cultures are the presence of media flow, albeit intermittent, and increased throughput compared with other microfluidic models. However, OrganoPlate 3-lane 40 model appeared to offer only limited (eg, MRP-mediated transport) advantages in terms of either gene expression or functional transport when compared with the multiwell plate culture conditions. Although OrganoPlate 3-lane 40 can be used to study cellular uptake and direct toxic effects of small molecules, it may have limited utility for drug transport studies. Overall, this study offers refined experimental protocols and comprehensive comparative data on the function of RPETCs in traditional multiwell culture and microfluidic OrganoPlate 3-lane 40, information that will be invaluable for the prospective end-users of in vitro models of the human proximal tubule.

Therapeutic ultrasound versus injection of local anesthetic in the treatment of women with chronic pelvic pain secondary to abdominal myofascial syndrome: a randomized clinical trial.

BACKGROUND: Chronic pelvic pain (CPP) is defined as recurrent or continuous pain in the lower abdomen or pelvis, either non-menstrual or noncyclical, lasting for at least 6 months. There is strong evidence that up to 85% of patients with CPP have serious dysfunctions of the musculoskeletal system, including abdominal myofascial pain syndrome (AMPS). AMPS is characterized by intense and deep abdominal pain, originating from hyperirritable trigger points, usually located within a musculoskeletal band or its lining fascia. In the literature, there are few studies that address AMPS. OBJECTIVES: To evaluate and compare the efficacy of therapeutic ultrasound (TUS) and injection of local anesthetic (IA) to improve pain in women with abdominal myofascial syndrome secondary to CPP. STUDY DESIGN: Randomized controlled clinical trial. SETTING: Tertiary University Hospital. MATERIALS AND METHODS: A randomized clinical trial was conducted, patients were allocated to two types of treatment: group TUS (n = 18), and group IA (n = 20). The instruments used for evaluation and reassessment were the Visual Analog Scale, Numerical Categorical Scale, McGill Pain Questionnaire, and SF-36 quality of life assessment questionnaire. They were evaluated before starting treatment, 1 week after the end of treatment, and at 1, 3, and 6 months. RESULTS: TUS and IA were effective in reducing clinical pain and improving quality of life through the variables analyzed among study participants. There was no significant difference between groups. LIMITATIONS: absence of blinding; exclusion of women with comorbidities and other causes of CPP, the absence of a placebo group, the difference between the number of sessions used for each technique, and the COVID-19. CONCLUSION: Treatment with TUS and IA were effective in reducing clinical pain and improving quality of life in women with AMPS secondary to CPP. TRAIL REGISTRATION: We declare that this clinical trial has been registered under the number [(ReBEC) no. RBR-39czsv] on 07/18/2018 in the Brazilian Registry of Clinical Trials.

Ready for regulatory use: NAMs and NGRA for chemical safety assurance.

New approach methodologies (NAMs) that do not use experimental animals are, in certain settings, entirely appropriate for assuring the safety of chemical ingredients, although regulatory adoption has been slow. In this opinion article we discuss how scientific advances that utilize NAMs to certify systemic safety are available now and merit broader acceptance within the framework of next generation risk assessments (NGRA).

Are Non-animal Systemic Safety Assessments Protective? A Toolbox and Workflow.

An important question in toxicological risk assessment is whether non-animal new approach methodologies (NAMs) can be used to make safety decisions that are protective of human health, without being overly conservative. In this work, we propose a core NAM toolbox and workflow for conducting systemic safety assessments for adult consumers. We also present an approach for evaluating how protective and useful the toolbox and workflow are by benchmarking against historical safety decisions. The toolbox includes physiologically based kinetic (PBK) models to estimate systemic Cmax levels in humans, and 3 bioactivity platforms, comprising high-throughput transcriptomics, a cell stress panel, and in vitro pharmacological profiling, from which points of departure are estimated. A Bayesian model was developed to quantify the uncertainty in the Cmax estimates depending on how the PBK models were parameterized. The feasibility of the evaluation approach was tested using 24 exposure scenarios from 10 chemicals, some of which would be considered high risk from a consumer goods perspective (eg, drugs that are systemically bioactive) and some low risk (eg, existing food or cosmetic ingredients). Using novel protectiveness and utility metrics, it was shown that up to 69% (9/13) of the low risk scenarios could be identified as such using the toolbox, whilst being protective against all (5/5) the high-risk ones. The results demonstrated how robust safety decisions could be made without using animal data. This work will enable a full evaluation to assess how protective and useful the toolbox and workflow are across a broader range of chemical-exposure scenarios.

Microphysiological Systems Evaluation: Experience of TEX-VAL Tissue Chip Testing Consortium.

Much has been written and said about the promise and excitement of microphysiological systems, miniature devices that aim to recreate aspects of human physiology on a chip. The rapid explosion of the offerings and persistent publicity placed high expectations on both product manufacturers and regulatory agencies to adopt the data. Inevitably, discussions of where this technology fits in chemical testing paradigms are ongoing. Some end-users became early adopters, whereas others have taken a more cautious approach because of the high cost and uncertainties of their utility. Here, we detail the experience of a public-private collaboration established for testing of diverse microphysiological systems. Collectively, we present a number of considerations on practical aspects of using microphysiological systems in the context of their applications in decision-making. Specifically, future end-users need to be prepared for extensive on-site optimization and have access to a wide range of imaging and other equipment. We reason that cells, related reagents, and the technical skills of the research staff, not the devices themselves, are the most critical determinants of success. Extrapolation from concentration-response effects in microphysiological systems to human blood or oral exposures, difficulties with replicating the whole organ, and long-term functionality remain as critical challenges. Overall, we conclude that it is unlikely that a rodent- or human-equivalent model is achievable through a finite number of microphysiological systems in the near future; therefore, building consensus and promoting the gradual incorporation of these models into tiered approaches for safety assessment and decision-making is the sensible path to wide adoption.

Fisura anal complicada con leucemia mielomonocitica, reporte de un caso / Anal fissure complicated with myelomonocytic leukemia, case report

La patología ano rectal y perineal en pacientes con leucemia son frecuentes, se ha mostrado una relación con el conteo de neurotróficos en pacientes con leucemia como factor de riesgo para la aparición de las mismas y su evolución, con peores pronósticos en aquellos que la enfermedad se encuentre activa, presentamos el caso de una paciente femenina de 12 años con el diagnostico de leucemia mielomonocitica que presento una fisura anal complicada, donde se ve una relación entre sus niveles de neutrófilos y el desarrollo de una fisura anal complicada.

Beyond AOPs: A Mechanistic Evaluation of NAMs in DART Testing.

New Approach Methodologies (NAMs) promise to offer a unique opportunity to enable human-relevant safety decisions to be made without the need for animal testing in the context of exposure-driven Next Generation Risk Assessment (NGRA). Protecting human health against the potential effects a chemical may have on embryo-foetal development and/or aspects of reproductive biology using NGRA is particularly challenging. These are not single endpoint or health effects and risk assessments have traditionally relied on data from Developmental and Reproductive Toxicity (DART) tests in animals. There are numerous Adverse Outcome Pathways (AOPs) that can lead to DART, which means defining and developing strict testing strategies for every AOP, to predict apical outcomes, is neither a tenable goal nor a necessity to ensure NAM-based safety assessments are fit-for-purpose. Instead, a pragmatic approach is needed that uses the available knowledge and data to ensure NAM-based exposure-led safety assessments are sufficiently protective. To this end, the mechanistic and biological coverage of existing NAMs for DART were assessed and gaps to be addressed were identified, allowing the development of an approach that relies on generating data relevant to the overall mechanisms involved in human reproduction and embryo-foetal development. Using the knowledge of cellular processes and signalling pathways underlying the key stages in reproduction and development, we have developed a broad outline of endpoints informative of DART. When the existing NAMs were compared against this outline to determine whether they provide comprehensive coverage when integrated in a framework, we found them to generally cover the reproductive and developmental processes underlying the traditionally evaluated apical endpoint studies. The application of this safety assessment framework is illustrated using an exposure-led case study.

Evaluation of Varian's SmartAdapt for clinical use in radiation therapy for patients with thoracic lesions.

INTRODUCTION: Deformable image registration (DIR) is a required tool in any adaptive radiotherapy program to help account for anatomical changes that occur during a multifraction treatment. SmartAdapt is a DIR tool from Varian incorporated within the eclipse treatment planning system, that can be used for contour propagation and transfer of PET, MRI, or computed tomography (CT) data. The purpose of this work is to evaluate the registration and contour propagation accuracy of SmartAdapt for thoracic CT studies using the guidelines from AAPM TG 132. METHODS: To evaluate the registration accuracy of SmartAdapt the mean target registration error (TRE) was measured for ten landmarked 4DCT images from the https://www.dir-labs.com/ which included 300 landmarks matching the inspiration and expiration phase images. To further characterize the registration accuracy, the magnitude of deformation for each 4DCT was measured and compared against the mean TRE for each study. Contour propagation accuracy was evaluated using 22 randomly selected lung cancer cases from our center where there was either a replan, or the patient was treated for a new lesion within the lung. Contours evaluated included the right and left lung, esophagus, spinal canal, heart and the GTV and the results were quantified using the DICE similarity coefficient. RESULTS: The mean TRE from all ten cases was 1.89 mm, the maximum mean TRE per case was 3.8 mm from case #8, which also had the most landmark pairs with displacements >2 cm. For contour propagation accuracy, the DICE coefficient results for left lung, right lung, heart, esophagus, and spinal canal were 0.93, 0.94, 0.90, 0.61, and 0.82 respectively. CONCLUSION: The results from our study demonstrate that for thoracic images SmartAdapt in most cases will be accurate to below 2 mm in registration error unless there is deformation greater than 2 cm.

Avaliação da ferida cirúrgica: Documentação de enfermagem / Surgical wound assessment: Nursing documentation

As organizações de saúde exigem dos seus profissionais responsabilidade na prestação de cuidados, tendo em conta os padrões de garantia e melhoria contínua da qualidade. Os registos de enfermagem devem refletir a qualidade dos cuidados e traduzirem os cuidados prestados e a eficácia dos mesmos. A informação acerca da pessoa alvo dos cuidados, deve ser precisa, significativa e sintética e versar as diversas categorias de informação, tendo em conta as funções autónomas e interdependentes do enfermeiro de acordo com os princípios ético científicos que regem a profissão. Partindo da questão de investigação ?O que é valorizado pelos enfermeiros nos registos de avaliação da ferida cirúrgica na fase pré-deiscência nos doentes submetidos a cirurgia abdominal?? foi definido o objetivo geral analisar na documentação de enfermagem, prévia ao diagnostico de deiscência, que possa indiciar complicações da ferida cirúrgica em doentes submetidos a cirurgia abdominal e, os objetivos específicos caraterizar o perfil do doente que desenvolveu deiscência e identificar registos de sinais e sintomas sugestivos de complicação da ferida cirúrgica. Trata-se de um estudo misto, retrospetivo de base documental com amostra acidental, constituída por 70 registos de processos de utentes que desenvolveram deiscência de ferida cirúrgica abdominal, internados entre janeiro de 2015 a dezembro de 2017, num serviço de cirurgia geral de um hospital distrital do centro do país. Análise documental de enfermagem mostrou-se escassez e pouco sistematizada, não refletindo a globalidade dos cuidados prestados. Contudo, foi possível identificar caraterísticas comuns do doente que desenvolveu deiscência e alguns sinais e sintomas sugestivos de complicações na ferida cirúrgica. Assim, a maioria dos doentes eram do sexo masculino (61,4%), com idade média de 71,21 anos, obesos ou com excesso de peso (60,1%). A maioria (58,6%) das deiscências ocorreram em doentes que fizeram cirurgia de urgência, 40% por patologia gastrintestinal e 37,1% oncológica. Na avaliação da dor, verificou-se que a dor média até ao dia da deiscência foi de (2,16) sendo ligeiramente superior á dor global que se fixou em (1,99). A temperatura global média dos doentes incluídos foi de 37,16ºC. Encontraram-se outros indicadores que podem traduzir complicação da ferida como: penso repassado, exsudato purulento ou hematopurulento, taquicardia, vómitos, complicações gastrointestinais, agitação/confusão e anemia. Embora os enfermeiros reconheçam a importância da comunicação escrita para a continuidade dos cuidados, observa-se na prática clínica, que esta é por vezes negligenciada, uma vez que os registos, quando realizados, são frequentemente escassos e incompletos não refletindo os cuidados prestados.

Ashi Acupuncture Versus Local Anesthetic Trigger Point Injections in the Treatment of Abdominal Myofascial Pain Syndrome: A Randomized Clinical Trial.

BACKGROUND: Chronic pelvic pain (CPP) is defined as recurrent or continuous pain in the lower abdomen or pelvis, non-menstrual or non-cyclic, lasting at least 6 months. There is strong evidence that up to 85% of patients with CPP have serious dysfunction of the musculoskeletal system, including abdominal myofascial syndrome (AMPS). AMPS is characterized as deep abdominal pain, originating from hyperirritable trigger points, usually located within a musculoskeletal range or its fascia of coating. In the literature, there are few studies that address AMPS. OBJECTIVE: This study aimed to compare the responses of ashi acupuncture treatment and local anesthetic injection in the treatment of chronic pelvic pain secondary to abdominal myofascial pain syndrome in women. STUDY DESIGN: Randomized controlled clinical trial. SETTING: Tertiary University Hospital. METHODS: Women with a clinical diagnosis of CPP secondary to AMPS were randomized and evaluated using instruments to assess clinical pain, namely, the visual analogue scale (VAS), numerical categorial scale (NCS), and the McGill Questionnaire, after receiving treatment with ashi acupuncture (group A, n = 16) or local anesthetic injections (group B, n = 19). They were reevaluated after one week and one, 3, and 6 months after each treatment, in addition to assessments of pain and adverse events performed during the sessions. RESULTS: Ashi acupuncture and local anesthetic injections were both effective in reducing clinical pain assessed through the analyzed variables among study participants. There was no difference between the groups and there was a strong correlation between these pain assessment instruments. LIMITATIONS: The absence of blinding to the different forms of treatment among the patients and the researcher directly involved in the treatment, the absence of a placebo group, the selective exclusion of women with comorbidities and other causes of CPP, and the difference between the number of sessions used for each technique. CONCLUSION: Treatments with ashi acupuncture and local anesthetic injections were effective in reducing clinical pain in women with abdominal myofascial pain syndrome.

Identifying and Characterizing Stress Pathways of Concern for Consumer Safety in Next-Generation Risk Assessment.

Many substances for which consumer safety risk assessments need to be conducted are not associated with specific toxicity modes of action, but rather exhibit nonspecific toxicity leading to cell stress. In this work, a cellular stress panel is described, consisting of 36 biomarkers representing mitochondrial toxicity, cell stress, and cell health, measured predominantly using high content imaging. To evaluate the panel, data were generated for 13 substances at exposures consistent with typical use-case scenarios. These included some that have been shown to cause adverse effects in a proportion of exposed humans and have a toxicological mode-of-action associated with cellular stress (eg, doxorubicin, troglitazone, and diclofenac), and some that are not associated with adverse effects due to cellular stress at human-relevant exposures (eg, caffeine, niacinamide, and phenoxyethanol). For each substance, concentration response data were generated for each biomarker at 3 timepoints. A Bayesian model was then developed to quantify the evidence for a biological response, and if present, a credibility range for the estimated point of departure (PoD) was determined. PoDs were compared with the plasma Cmax associated with the typical substance exposures, and indicated a clear differentiation between "low" risk and "high" risk chemical exposure scenarios. Developing robust methods to characterize the in vitro bioactivity of xenobiotics is an important part of non-animal safety assessment. The results presented in this work show that the cellular stress panel can be used, together with other new approach methodologies, to identify chemical exposures that are protective of consumer health.

A Next-Generation Risk Assessment Case Study for Coumarin in Cosmetic Products.

Next-Generation Risk Assessment is defined as an exposure-led, hypothesis-driven risk assessment approach that integrates new approach methodologies (NAMs) to assure safety without the use of animal testing. These principles were applied to a hypothetical safety assessment of 0.1% coumarin in face cream and body lotion. For the purpose of evaluating the use of NAMs, existing animal and human data on coumarin were excluded. Internal concentrations (plasma Cmax) were estimated using a physiologically based kinetic model for dermally applied coumarin. Systemic toxicity was assessed using a battery of in vitro NAMs to identify points of departure (PoDs) for a variety of biological effects such as receptor-mediated and immunomodulatory effects (Eurofins SafetyScreen44 and BioMap Diversity 8 Panel, respectively), and general bioactivity (ToxCast data, an in vitro cell stress panel and high-throughput transcriptomics). In addition, in silico alerts for genotoxicity were followed up with the ToxTracker tool. The PoDs from the in vitro assays were plotted against the calculated in vivo exposure to calculate a margin of safety with associated uncertainty. The predicted Cmax values for face cream and body lotion were lower than all PoDs with margin of safety higher than 100. Furthermore, coumarin was not genotoxic, did not bind to any of the 44 receptors tested and did not show any immunomodulatory effects at consumer-relevant exposures. In conclusion, this case study demonstrated the value of integrating exposure science, computational modeling and in vitro bioactivity data, to reach a safety decision without animal data.

Application of physiologically based kinetic (PBK) modelling in the next generation risk assessment of dermally applied consumer products.

Next Generation Risk Assessment (NGRA) is a procedure that integrates new approach methodologies (NAMs) to assure safety of a product without generating data from animal testing. One of the major challenges in the application of NGRA to consumer products is how to extrapolate from the in vitro points of departure (PoDs) to the human exposure level associated with product use. To bridge the gap, physiologically based kinetic (PBK) modelling is routinely used to predict systemic exposure (Cmax or AUC) from external exposures. A novel framework was developed for assessing the exposure of new ingredients in dermally applied products based on the construction of PBK models describing consumer habits and practices, formulation type, and ADME (absorption, distribution, metabolism and excretion) properties exclusively obtained from NAMs. This framework aims to quantify and reduce the uncertainty in predictions and is closely related to the risk assessment process (i.e., is the margin of safety sufficient to cover the uncertainties in the extrapolation between the in vitro and in vivo toxicodynamics and toxicokinetics?). Coumarin, caffeine, and sulforaphane in four product types (kitchen cleaner liquid, face cream, shampoo, and body lotion) were selected to exemplify how this framework could be used in practise. Our work shows initial levels of the framework provide a conservative estimate of Cmax in most cases which can be refined using sensitivity analysis to inform the choice of follow-up in vitro experiments. These case studies show the framework can increase confidence in use of PBK predictions for safety assessment.

A Safe and Stable Neonatal Vaccine Targeting GAPDH Confers Protection against Group B Streptococcus Infections in Adult Susceptible Mice.

Group B Streptococcus (GBS), a commensal organism, can turn into a life-threatening pathogen in neonates and elderly, or in adults with severe underlying diseases such as diabetes. We developed a vaccine targeting the GBS glyceraldehyde-3-phosphate dehydrogenase (GAPDH), a glycolytic enzyme detected at the bacterial surface, which was proven to be effective in a neonatal mouse model of infection. Since this bacterium has emerged as an important pathogen in non-pregnant adults, here we investigated whether this vaccine also confers protection in an adult susceptible and in a diabetic mouse model of infection. For immunoprotection studies, sham or immunized adult mice were infected with GBS serotype Ia and V strains, the two most prevalent serotypes isolated in adults. Sham and vaccinated mice were also rendered diabetic and infected with a serotype V GBS strain. For toxicological (pre-clinical) studies, adult mice were vaccinated three times, with three concentrations of recombinant GAPDH adjuvanted with Allydrogel, and the toxicity parameters were evaluated twenty-four hours after the last immunization. For the stability tests, the vaccine formulations were maintained at 4°C for 6 and 12 months prior immunization. The results showed that all tested doses of the vaccine, including the stability study formulations, were immunogenic and that the vaccine was innocuous. The organs (brain, blood, heart, and liver) of vaccinated susceptible or diabetic adult mice were significantly less colonized compared to those of control mice. Altogether, these results demonstrate that the GAPDH-based vaccine is safe and stable and protects susceptible and diabetic adult mice against GBS infections. It is therefore a promising candidate as a global vaccine to prevent GBS-induced neonatal and adult diseases.

Pesticides exposure as etiological factors of Parkinson's disease and other neurodegenerative diseases--a mechanistic approach.

The etiology of most neurodegenerative disorders is multifactorial and consists of an interaction between environmental factors and genetic predisposition. The role of pesticide exposure in neurodegenerative disease has long been suspected, but the specific causative agents and the mechanisms underlying are not fully understood. For the main neurodegenerative diseases such as Parkinson's disease, Alzheimer's disease and amyotrophic lateral sclerosis there are evidences linking their etiology with long-term/low-dose exposure to pesticides such as paraquat, maneb, dieldrin, pyrethroids and organophosphates. Most of these pesticides share common features, namely the ability to induce oxidative stress, mitochondrial dysfunction, α-synuclein fibrillization and neuronal cell loss. This review aims to clarify the role of pesticides as environmental risk factors in genesis of idiopathic PD and other neurological syndromes. For this purpose, the most relevant epidemiological and experimental data is highlighted in order to discuss the molecular mechanisms involved in neurodegeneration.

Crucial CD8(+) T-lymphocyte cytotoxic role in amphotericin B nanospheres efficacy against experimental visceral leishmaniasis.

This work aims to develop poly(d,l-lactide-co-glycolide) (PLGA)-nanospheres containing amphotericin B (AmB) with suitable physicochemical properties and anti-parasitic activity for visceral leishmaniasis (VL) therapy. When compared with unloaded-PLGA-nanospheres, the AmB-loaded PLGA-nanospheres displayed an increased particle size without affecting the polydispersity and its negative surface charge. AmB stability in the PLGA-nanospheres was >90% over 60-days at 30°C. The AmB-PLGA-nanospheres demonstrated significant in vitro and in vivo efficacy and preferential accumulation in the visceral organs. In addition, an immune-modulatory effect was observed in mice treated with AmB-PLGA-nanospheres, correlating with improved treatment efficacy. The in vitro cytotoxic response of the T-lymphocytes revealed that AmB-PLGA-nanospheres efficacy against VL infection was strictly due to the action of CD8(+)- but not CD4(+)-T lymphocytes. Overall, we demonstrate a crucial role for CD8(+) cytotoxic T lymphocytes in the efficacy of AmB-PLGA nanospheres, which could represent a potent and affordable alternative for VL therapy. FROM THE CLINICAL EDITOR: This study demonstrates a crucial role for CD8+ T lymphocytes in eliminating visceral leishmaniasis in a murine model by enhancing the cytotoxic efficacy of CD8+ T-cells via amphotericin-B-PLGA nanospheres, paving a way to a unique, potentially more potent and cost-effective therapeutic strategy.

Lysine acetylsalicylate increases the safety of a paraquat formulation to freshwater primary producers: a case study with the microalga Chlorella vulgaris.

Large amounts of herbicides are presently used in the industrialized nations worldwide, with an inexorable burden to the environment, especially to aquatic ecosystems. Primary producers such as microalgae are of especial concern because they are vital for the input of energy into the ecosystem and for the maintenance of oxygen in water on which most of other marine life forms depend on. The herbicide paraquat (PQ) is known to cause inhibition of photosynthesis and irreversible damage to photosynthetic organisms through generation of reactive oxygen species in a light-dependent manner. Previous studies have led to the development of a new formulation of PQ containing lysine acetylsalicylate (LAS) as an antidote, which was shown to prevent the mammalian toxicity of PQ, while maintaining the herbicidal effect. However, the safety of this formulation to primary producers in relation to commercially available PQ formulations has hitherto not been established. Therefore, the aim of this study was to evaluate the toxicity of the PQ+LAS formulation in comparison with the PQ, using Chlorella vulgaris as a test organism. Effect criterion was the inhibition of microalgal population growth. Following a 96 h exposure to increasing concentrations of PQ, C. vulgaris growth was almost completely inhibited, an effect that was significantly prevented by LAS at the proportion used in the formulation (PQ+LAS) 1:2 (mol/mol), while the highest protection was achieved at the proportion of 1:8. In conclusion, the present work demonstrated that the new formulation with PQ+LAS has a reduced toxicity to C. vulgaris when compared to Gramoxone(®).

New formulation of paraquat with lysine acetylsalicylate with low mammalian toxicity and effective herbicidal activity.

BACKGROUND: Currently, the commercial formulations of the herbicide paraquat are highly toxic to humans, and no effective antidote is available for paraquat poisoning. The aim of the present study was to develop a safe formulation, combining paraquat and the known antidote lysine acetylsalicylate. The toxicity of a mixture of Gramoxone® (20% paraquat) and lysine acetylsalicylate in adult Wistar male rats and the herbicidal efficacy against grass lawn (50% of Poa pratensis and 50% of Festuca arundinacea) were evaluated. This new formulation was administered to Wistar rats by gavage at 125 mg kg(-1) of paraquat ion and lysine acetylsalicylate at 79, 158 or 316 mg kg(-1) body weight, and the survival rate was observed for 30 days. RESULTS: The survival rate of the paraquat group was only 40%, while lysine acetylsalicylate provided effective protection, with full survival observed in the groups that received 125 mg kg(-1) of paraquat ion and 316 mg kg(-1) of lysine acetylsalicylate. Both formulations of paraquat, either in the absence or in the presence of lysine acetylsalicylate, provided the same herbicidal activity against the tested herbal species. CONCLUSIONS: The present formulation of paraquat containing lysine acetylsalicylate, significantly decreases mammalian toxicity while maintaining effective herbicidal activity.