Characterization of consumption and costs of antimicrobials in intensive care units in a Brazilian tertiary hospital.

Background: The consumption of antimicrobials and the growing resistance of infectious agents to these drugs are not related only to health issues, but also to economic parameters. Objectives: The study objective was to evaluate the consumption of antimicrobials in General and Covid-19 Intensive Care Units (ICUs) and the impact on institutional costs in the largest institute of a tertiary public hospital. Methods: This is a quantitative and retrospective study, which analyzed consumption, through the Defined Daily Dose (DDD), and the annual direct cost of antimicrobials in Reais (R$) and Dollars (US$), from January to December 2021. Results: The total annual consumption (DDD/1000 patient-day) of antimicrobials in the ICUs was 14,368.85. ß-Lactams had the highest total annual value, with a DDD/1000 patient-day of 7062.98, being meropenem the antimicrobial that reached the highest consumption (3107.20), followed by vancomycin (2322.6). Total consumption was higher in Covid-19 ICUs than in General ICUs, and the annual direct cost of antimicrobials in ICUs was US$560,680.79. Conclusions: The study showed high consumption of broad-spectrum antimicrobials, highlighting the importance of structuring programs to manage the use of antimicrobials, both to reduce antimicrobial consumption and hospital costs, consolidating rational use even in pandemic scenarios.

A comparative study of visual outcome in patients with optic neuritis treated with five or seven days of intravenous corticosteroid treatment.

BACKGROUND: Optic neuritis (ON), a major cause of visual impairment in young adults, is generally associated with rapid visual recovery when treated with intravenous methylprednisolone treatment (IVMPT). However, the optimal duration of such treatment is unknown, ranging from three to seven days in clinical practice. We aimed to compare the visual recovery in patients treated with 5-day or 7-day duration IVMPT. METHODS: We performed a retrospective cohort study of consecutive patients with ON in São Paulo, Brazil, from 2016 to 2021. We compared the proportion of participants with visual impairment in 5-day and 7-day treatment schedules at discharge, at 1 month and between 6 and 12 months after the diagnosis of ON. The findings were adjusted to age, severity of the visual impairment, co-intervention with plasma exchange, time from symptom onset to IVMPT and the etiology of the ON to mitigate indication bias. RESULTS: We included 73 patients with ON treated with 5 or 7-day duration of 1 g/d intravenous methylprednisolone therapy. Visual impairment at 6-12 months in the 5-day or the 7-day treatment groups was similar (57% x 59%, p > 0.9, Odds Ratio 1.03 [95% CI 0.59-1.84]). The results were similar after adjusting for prognostic variables and when observed at different time points. CONCLUSION: Visual recovery is similar in patients treated with 5-day and 7-day duration treatments of 1 g/day intravenous methylprednisolone, suggesting a ceiling effect. Limiting the duration of the treatment can reduce hospital stay and costs, without interfering with clinical benefit.

Effective Pre-Clinical Treatment of Fish Envenoming with Polyclonal Antiserum.

Envenomation by venomous fish, although not always fatal, is capable of causing damage to homeostasis by activating the inflammatory process, with the formation of edema, excruciating pain, necrosis that is difficult to heal, as well as hemodynamic and cardiorespiratory changes. Despite the wide variety of pharmacological treatments used to manage acute symptoms, none are effective in controlling envenomation. Knowing the essential role of neutralizing polyclonal antibodies in the treatment of envenoming for other species, such as snakes, this work aimed to produce a polyclonal antiserum in mice and test its ability to neutralize the main toxic effects induced by the venoms of the main venomous Brazilian fish. We found that the antiserum recognizes the main toxins present in the different venoms of Thalassophryne nattereri, Scorpaena plumieri, Potamotrygon gr. Orbignyi, and Cathorops spixii and was effective in pre-incubation trials. In an independent test, the antiserum applied immediately to the topical application of T. nattereri, P. gr orbygnyi, and C. spixii venoms completely abolished the toxic effects on the microcirculation, preventing alterations such as arteriolar contraction, slowing of blood flow in postcapillary venules, venular stasis, myofibrillar hypercontraction, and increased leukocyte rolling and adherence. The edematogenic and nociceptive activities induced by these venoms were also neutralized by the immediate application of the antiserum. Importantly, the antiserum prevented the acute inflammatory response in the lungs induced by the S. plumieri venom. The success of antiserum containing neutralizing polyclonal antibodies in controlling the toxic effects induced by different venoms offers a new strategy for the treatment of fish envenomation in Brazil.

Inflammasome Coordinates Senescent Chronic Wound Induced by Thalassophryne nattereri Venom.

Thalassophryne nattereri toadfish (niquim) envenomation, common in the hands and feet of bathers and fishermen in the north and northeast regions of Brazil, is characterized by local symptoms such as immediate edema and intense pain. These symptoms progress to necrosis that lasts for an extended period of time, with delayed healing. Wound healing is a complex process characterized by the interdependent role of keratinocytes, fibroblasts, and endothelial and innate cells such as neutrophils and macrophages. Macrophages and neutrophils are actively recruited to clear debris during the inflammatory phase of wound repair, promoting the production of pro-inflammatory mediators, and in the late stage, macrophages promote tissue repair. Our hypothesis is that injury caused by T. nattereri venom (VTn) leads to senescent wounds. In this study, we provide valuable information about the mechanism(s) behind the dysregulated inflammation in wound healing induced by VTn. We demonstrate in mouse paws injected with the venom the installation of γH2AX/p16Ink4a-dependent senescence with persistent neutrophilic inflammation in the proliferation and remodeling phases. VTn induced an imbalance of M1/M2 macrophages by maintaining a high number of TNF-α-producing M1 macrophages in the wound but without the ability to eliminate the persistent neutrophils. Chronic neutrophilic inflammation and senescence were mediated by cytokines such as IL-1α and IL-1ß in a caspase-1- and caspase-11-dependent manner. In addition, previous blocking with anti-IL-1α and anti-IL-ß neutralizing antibodies and caspase-1 (Ac YVAD-CMK) and caspase-11 (Wedelolactone) inhibitors was essential to control the pro-inflammatory activity of M1 macrophages induced by VTn injection, skewing towards an anti-inflammatory state, and was sufficient to block neutrophil recruitment and senescence.

The Anti-Inflammatory Peptide TnP Is a Candidate Molecule for Asthma Treatment.

Asthma is the most common chronic lung disease, with increasing morbidity and mortality worldwide. Accumulation of peribronchial leukocytes is the hallmark of asthma, in particular, eosinophils, which have been reported as the primary cell associated with the induction of airway hyperresponsiveness. Continued exacerbation and accumulation of other leukocytes, such as neutrophils, Th1, and Th17 cells correlate with many of the long-term effects of asthma, such as airway remodeling. We have patented the TnP family of synthetic cyclic peptides, which is in the preclinical phase of developmental studies for chronic inflammatory diseases. The aim of this work was to investigate whether TnP could show anti-inflammatory activity in a murine model of asthma that includes a mixed phenotype of eosinophilic and neutrophilic inflammation. For this, Balb/c mice, sensitized with OVA and exposed to 1% challenge with OVA aerosol, were submitted to prophylactic treatment, receiving TnP at 0.3 mg/kg orally, 1 h before each challenge. We found that sensitized mice challenged with OVA and treated with TnP showed no airway hyperreactivity or lung remodeling. TnP acts systemically in secondary lymphoid organs and locally in the lung, inhibiting the production of Th2/Th17 cytokines. Furthermore, TnP prevented the infiltration of eosinophils and neutrophils in the BAL and lung tissue, inhibited the production of IgE/IgG1, prevented hyperplasia of mucus-producing cells, and decreased the thickening and deposition of sub-epithelial collagen. Our results showed TnP as a candidate molecule for the treatment of airway remodeling associated with inflammatory diseases, such as asthma.

Effective pre-clinical treatment of fish envenoming with polyclonal antiserum

Envenomation by venomous fish, although not always fatal, is capable of causing damage to homeostasis by activating the inflammatory process, with the formation of edema, excruciating pain, necrosis that is difficult to heal, as well as hemodynamic and cardiorespiratory changes. Despite the wide variety of pharmacological treatments used to manage acute symptoms, none are effective in controlling envenomation. Knowing the essential role of neutralizing polyclonal antibodies in the treatment of envenoming for other species, such as snakes, this work aimed to produce a polyclonal antiserum in mice and test its ability to neutralize the main toxic effects induced by the venoms of the main venomous Brazilian fish. We found that the antiserum recognizes the main toxins present in the different venoms of Thalassophryne nattereri, Scorpaena plumieri, Potamotrygon gr. Orbignyi, and Cathorops spixii and was effective in pre-incubation trials. In an independent test, the antiserum applied immediately to the topical application of T. nattereri, P. gr orbygnyi, and C. spixii venoms completely abolished the toxic effects on the microcirculation, preventing alterations such as arteriolar contraction, slowing of blood flow in postcapillary venules, venular stasis, myofibrillar hypercontraction, and increased leukocyte rolling and adherence. The edematogenic and nociceptive activities induced by these venoms were also neutralized by the immediate application of the antiserum. Importantly, the antiserum prevented the acute inflammatory response in the lungs induced by the S. plumieri venom. The success of antiserum containing neutralizing polyclonal antibodies in controlling the toxic effects induced by different venoms offers a new strategy for the treatment of fish envenomation in Brazil.

Inflammasome coordinates senescent chronic wound induced by Thalassophryne nattereri venom

Thalassophryne nattereri toadfish (niquim) envenomation, common in the hands and feet of bathers and fishermen in the north and northeast regions of Brazil, is characterized by local symptoms such as immediate edema and intense pain. These symptoms progress to necrosis that lasts for an extended period of time, with delayed healing. Wound healing is a complex process characterized by the interdependent role of keratinocytes, fibroblasts, and endothelial and innate cells such as neutrophils and macrophages. Macrophages and neutrophils are actively recruited to clear debris during the inflammatory phase of wound repair, promoting the production of pro-inflammatory mediators, and in the late stage, macrophages promote tissue repair. Our hypothesis is that injury caused by T. nattereri venom (VTn) leads to senescent wounds. In this study, we provide valuable information about the mechanism(s) behind the dysregulated inflammation in wound healing induced by VTn. We demonstrate in mouse paws injected with the venom the installation of γH2AX/p16Ink4a-dependent senescence with persistent neutrophilic inflammation in the proliferation and remodeling phases. VTn induced an imbalance of M1/M2 macrophages by maintaining a high number of TNF-α-producing M1 macrophages in the wound but without the ability to eliminate the persistent neutrophils. Chronic neutrophilic inflammation and senescence were mediated by cytokines such as IL-1α and IL-1β in a caspase-1- and caspase-11-dependent manner. In addition, previous blocking with anti-IL-1α and anti-IL-β neutralizing antibodies and caspase-1 (Ac YVAD-CMK) and caspase-11 (Wedelolactone) inhibitors was essential to control the pro-inflammatory activity of M1 macrophages induced by VTn injection, skewing towards an anti-inflammatory state, and was sufficient to block neutrophil recruitment and senescence.

The anti-inflammatory peptide TnP is a candidate molecule for asthma treatment

Asthma is the most common chronic lung disease, with increasing morbidity and mortality worldwide. Accumulation of peribronchial leukocytes is the hallmark of asthma, in particular, eosinophils, which have been reported as the primary cell associated with the induction of airway hyperresponsiveness. Continued exacerbation and accumulation of other leukocytes, such as neutrophils, Th1, and Th17 cells correlate with many of the long-term effects of asthma, such as airway remodeling. We have patented the TnP family of synthetic cyclic peptides, which is in the preclinical phase of developmental studies for chronic inflammatory diseases. The aim of this work was to investigate whether TnP could show anti-inflammatory activity in a murine model of asthma that includes a mixed phenotype of eosinophilic and neutrophilic inflammation. For this, Balb/c mice, sensitized with OVA and exposed to 1% challenge with OVA aerosol, were submitted to prophylactic treatment, receiving TnP at 0.3 mg/kg orally, 1 h before each challenge. We found that sensitized mice challenged with OVA and treated with TnP showed no airway hyperreactivity or lung remodeling. TnP acts systemically in secondary lymphoid organs and locally in the lung, inhibiting the production of Th2/Th17 cytokines. Furthermore, TnP prevented the infiltration of eosinophils and neutrophils in the BAL and lung tissue, inhibited the production of IgE/IgG1, prevented hyperplasia of mucus-producing cells, and decreased the thickening and deposition of sub-epithelial collagen. Our results showed TnP as a candidate molecule for the treatment of airway remodeling associated with inflammatory diseases, such as asthma.

Análise das solicitações de medicamentos não padronizados de um hospital universitário terciário / Analysis of requests for non-standard medicines from a tertiary university hospital

Introdução: O uso extensivo de medicamentos não padronizados causa aumento de custos em saúde, além de potencial redução de segurança e uso racional de medicamentos. A Comissão de Farmácia e Terapêutica orienta a prescrição de medicamentos, por meio da avaliação e seleção de medicamentos a serem incluídos no formulário de medicamentos padronizados, com base nas melhores evidências científicas disponíveis e no perfil dos pacientes locais, promovendo o uso racional de medicamentos. O objetivo deste trabalho foi analisar as solicitações de fornecimento de medicamentos não padronizados na instituição. Métodos: Trata-se de um estudo observacional e descritivo onde foram analisadas as solicitações de medicamentos não padronizados realizadas entre fevereiro de 2016 e dezembro de 2021, identificando os medicamentos envolvidos e seus respectivos custos. Resultados: Foram realizadas 203 solicitações no período, sendo 174 incluídas no estudo. Os medicamentos que tiveram mais solicitações foram o rituximabe (41), a imunoglobulina humana (31), o sucralfato (23), a nitazoxanida (12) e o eltrombopague (7). As solicitações com maior custo foram as de imunoglobulina humana (US$ 799,702.38), rituximabe (US$ 717,320.26), eltrombopague (US$ 281,062.50), ruxolitinibe (US$ 167,867.46) e bortezomibe (US$ 149,033.52). As principais clínicas que solicitaram medicamentos não padronizado foram a neurologia (47), a hematologia (30), as moléstias infecciosas e parasitárias (17), e a anestesiologia (12). As solicitações de maior custo foram realizadas pela neurologia (US$ 145,519.08), hematologia (US$ 120,980.25), transplante de medula óssea (US$ 51,635.11) e dermatologia (US$ 44,813.40). Conclusão: O estudo demonstrou que há um fluxo estruturado de solicitação de medicamentos não padronizados na instituição, sendo uma importante ferramenta de gerenciamento dessas solicitações, evitando a aquisição desnecessária de itens que não compõem o elenco terapêutico do hospital.

Introduction: Widespread use of non-formulary drugs (NFD) increases cost and may reduce safety and rational use of medicines. The Pharmacy and Therapeutics Committee provides guidance on drug prescription by evaluating and selecting medications to be included in a hospital's formulary based on best scientific evidence available and local patients' profile, promoting rational use of medicines. The objective of this study was to assess non-formulary drugs prescriptions at a tertiary hospital. Methods: This was a retrospective study. NFD prescribed and its associated costs were assessed through NFD request forms received from February 2016 to December 2021. Results: A total of 203 NFD request forms were received, from which 174 were included in this study. The most frequently prescribed NFD included rituximab (n = 41), immunoglobulin (31), sucralfate (23), nitazoxanide (12), and eltrombopag (7), with the highest costs being with immunoglobulin (US$ 799,702.38), rituximab (US$ 717,320.26), eltrombopag (US$ 281,062.50), ruxolitinib (US$ 167,867.46), and bortezomib (US$ 149,033.52). The most frequent requesting specialties were neurology (n = 47), hematology (30), infectious disease (17) and anesthesiology (12), and highest costs requests were from neurology (US$ 145,519.08), hematology (US$ 120,980.25), bone marrow transplant unit (US$ 51,635.11), and dermatology (US$ 44,813.40). Conclusion: This study showed that a structured request flow for NFD prescription is a critical procedure in order to better manage drug prescription within the hospital, promoting rational use of medicines and preventing unnecessary spending with drugs for which the clinical indication may be covered by a drug already in the hospital's formulary.

COVID-19: como informações baseadas em evidências auxiliaram um hospital terciário durante o primeiro ano pandêmico / COVID-19: how evidence-based information supported a tertiary hospital during the first pandemic year

Introdução: Durante a pandemia de COVID-19, a necessidade por uma informação confiável, rápida e precisa desafiou os profissionais de saúde de todo o mundo. O objetivo deste trabalho foi avaliar e comparar as solicitações dos profissionais da saúde realizadas a um Centro de Informação Sobre Medicamentos (CIM) em um ano pré-pandêmico e durante o primeiro ano pandêmico. Métodos: Trata-se de um estudo quantitativo e retrospectivo, que analisou as perguntas realizadas ao CIM do Instituto Central do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (ICHCFMUSP) quanto ao seu assunto, classificação ATC dos medicamentos envolvidos e profissionais solicitantes. Resultados: Os resultados demonstram que, de maneira geral, durante o primeiro ano pandêmico houve um aumento de 454 perguntas (66,13%; p < 0,01). As dúvidas se referiam principalmente a questões de administração, estabilidade/compatibilidade e padronização do medicamento na instituição, sendo o farmacêutico o profissional que realizou maior número de questionamentos. Ao seccionar as perguntas, verificou-se que a maioria das informações solicitadas se referiram a agentes infecciosos, agentes que atuam no sangue/órgãos hematopoiéticos e sistema nervoso. Conclusão: Considerando o cenário pandêmico, com sobrecarga dos serviços de saúde, contratação em massa de novos profissionais e pouca disponibilidade de informações com embasamento científico, as evidências fornecidas pelo CIM, aliadas ao entendimento do quadro clínico de cada paciente, com certeza auxiliaram em um melhor desfecho clínico, bem como foram essenciais no uso racional de medicamentos no combate a pandemia de COVID-19.

Introduction: During the COVID-19 pandemic the need for reliable, fast and accurate information challenged healthcare professionals around the world. The aim of this study was to evaluate and compare the requests made by health professionals to a Drug Information Center (DIC) in a pre-pandemic year and during the first year of the pandemic. Methods: This is a quantitative and retrospective study that analyzed the solicitations made to the DIC of the Instituto Central do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (ICHCFMUSP) regarding its subject, ATC classification of drugs involved and requesting professionals. Results: The results show that, in general, during the first pandemic year there was an increase of 454 questions (66.13%; p < 0.01). The questions referred mainly to issues of administration, stability/compatibility and standardization of the medicines in the institution, being the pharmacist the professional who asked the most number of questions. When sectioning the questions, it was found that most of the information requested referred to infectious agents, agents that act on the blood/hematopoietic organs and the nervous system. Conclusion: Considering the pandemic scenario, with an overload of health services, large number of hires of new professionals and lack of availability of scientifically based information, the evidence provided by the DIC, combined with the understanding of clinical condition of each patient, certainly helped in a better outcome for each patient, as well as being essential in the rational use of medicines in the fight against the COVID-19 pandemic.

Brazilian perspective: antimicrobial stewardship in solid organ transplant.

BACKGROUND: The incidence of multidrug resistant organisms (MDROs) infections among solid organ transplant (SOT) patients is very high in Brazil. METHODS: This review will discuss antimicrobial use and resistance in SOT in Brazil, highlighting the main barriers and facilitators for implementation of an antimicrobial stewardship programme (ASP). RESULTS: The most common group of MDROs is carbapenem-resistant Gram-negative bacteria and vancomycin-resistant Enterococcus. Carbapenem-resistant Enterobacterales (CREs) are the most frequent MDROs and have been reported as donor-derived as well. Although ASPs are mandatory in the country, there is a lack of information regarding ASPs in SOT recipients. The main barriers for the implementation of ASPs in Brazilian hospitals are lack of electronic medical records, absence of national guidelines specific to SOT recipients, lack of recommendations on surveillance culture to evaluate colonization and transmission of donor-derived MDROs, limited availability of rapid diagnostic tests, and insufficient pharmacist and clinician time allocated to ASP activities in some SOT centers. CONCLUSIONS: The incidence of MDRO infections caused mainly by VREs and CREs is very high in the country. There is limited data regarding antimicrobial use among SOT recipients in Brazil. The absence of antimicrobial stewardship national guidelines specific to SOT recipients is one of the main barriers for the implementation of ASPs in Brazilian hospitals.

Pesticides and Their Impairing Effects on Epithelial Barrier Integrity, Dysbiosis, Disruption of the AhR Signaling Pathway and Development of Immune-Mediated Inflammatory Diseases.

The environmental and occupational risk we confront from agricultural chemicals increases as their presence in natural habitats rises to hazardous levels, building a major part of the exposome. This is of particular concern in low- and middle-income countries, such as Brazil, known as a leading producer of agricultural commodities and consumer of pesticides. As long as public policies continue to encourage the indiscriminate use of pesticides and governments continue to support this strategy instead of endorsing sustainable agricultural alternatives, the environmental burden that damages epithelial barriers will continue to grow. Chronic exposure to environmental contaminants in early life can affect crucial barrier tissue, such as skin epithelium, airways, and intestine, causing increased permeability, leaking, dysbiosis, and inflammation, with serious implications for metabolism and homeostasis. This vicious cycle of exposure to environmental factors and the consequent damage to the epithelial barrier has been associated with an increase in immune-mediated chronic inflammatory diseases. Understanding how the harmful effects of pesticides on the epithelial barrier impact cellular interactions mediated by endogenous sensors that coordinate a successful immune system represents a crucial challenge. In line with the epithelial barrier hypothesis, this narrative review reports the available evidence on the effects of pesticides on epithelial barrier integrity, dysbiosis, AhR signaling, and the consequent development of immune-mediated inflammatory diseases.

Impact of Pesticides on Human Health in the Last Six Years in Brazil.

Every year, Brazil intensifies its activity in agriculture and, as a result, it has become one of the biggest consumers of pesticides in the world. The high rate of these substances raises environmental and human health concerns. Therefore, we collected papers from PubMed, Scopus, Scielo, and Web of Science databases, from 2015 to 2021. After a blind selection using the software Rayyan QCRI by two authors, 51 studies were included. Researchers from the South and the Southeast Brazilian regions contributed to most publications, from areas that concentrate agricultural commodity complexes. Among the pesticides described in the studies, insecticides, herbicides, and fungicides were the most frequent. The articles reported multiple toxic effects, particularly in rural workers. The results obtained can be used to direct policies to reduce the use of pesticides, and to protect the health of the population.

Natterin-like depletion by CRISPR/Cas9 impairs zebrafish (Danio rerio) embryonic development.

BACKGROUND: The Natterin protein family was first discovered in the venom of the medically significant fish Thalassophryne nattereri, and over the last decade natterin-like genes have been identified in various organisms, notably performing immune-related functions. Previous findings support natterin-like genes as effector defense molecules able to activate multiprotein complexes driving the host innate immune response, notably due to the pore-forming function of the aerolysin superfamily members. Herein, employing a combination of the CRISPR/Cas9 depletion system, phenotype-based screening, and morphometric methods, we evaluated the role of one family member, LOC795232, in the embryonic development of zebrafish since it might be implicated in multiple roles and characterization of the null mutant is central for analysis of gene activity. RESULTS: Multiple sequence alignment revealed that the candidate natterin-like has the highest similarity to zebrafish aep1, a putative and better characterized fish-specific defense molecule from the same family. Compared to other species, zebrafish have many natterin-like copies. Whole-mount in situ hybridization confirmed the knockout and mutant embryos exhibited epiboly delay, growth retardation, yolk sac and heart edema, absent or diminished swim bladder, spinal defects, small eyes and head, heart dysfunction, and behavioral impairment. As previously demonstrated, ribonucleoproteins composed of Cas9 and duplex guide RNAs are effective at inducing mutations in the F0 zebrafish. CONCLUSIONS: The considerably high natterin-like copies in zebrafish compared to other species might be due to the teleost-specific whole genome duplication and followed by subfunctionalization or neofunctionalization. In the present work, we described some of the natterin-like features in the zebrafish development and infer that natterin-like proteins potentially contribute to the embryonary development and immune response.

Pesticides and their impairing effects on epithelial barrier integrity, dysbiosis, disruption of the AhR signaling pathway and development of immune-mediated inflammatory diseases

The environmental and occupational risk we confront from agricultural chemicals increases as their presence in natural habitats rises to hazardous levels, building a major part of the exposome. This is of particular concern in low- and middle-income countries, such as Brazil, known as a leading producer of agricultural commodities and consumer of pesticides. As long as public policies continue to encourage the indiscriminate use of pesticides and governments continue to support this strategy instead of endorsing sustainable agricultural alternatives, the environmental burden that damages epithelial barriers will continue to grow. Chronic exposure to environmental contaminants in early life can affect crucial barrier tissue, such as skin epithelium, airways, and intestine, causing increased permeability, leaking, dysbiosis, and inflammation, with serious implications for metabolism and homeostasis. This vicious cycle of exposure to environmental factors and the consequent damage to the epithelial barrier has been associated with an increase in immune-mediated chronic inflammatory diseases. Understanding how the harmful effects of pesticides on the epithelial barrier impact cellular interactions mediated by endogenous sensors that coordinate a successful immune system represents a crucial challenge. In line with the epithelial barrier hypothesis, this narrative review reports the available evidence on the effects of pesticides on epithelial barrier integrity, dysbiosis, AhR signaling, and the consequent development of immune-mediated inflammatory diseases.

Impact of pesticides on human health in the last six years in Brazil

Every year, Brazil intensifies its activity in agriculture and, as a result, it has become one of the biggest consumers of pesticides in the world. The high rate of these substances raises environmental and human health concerns. Therefore, we collected papers from PubMed, Scopus, Scielo, and Web of Science databases, from 2015 to 2021. After a blind selection using the software Rayyan QCRI by two authors, 51 studies were included. Researchers from the South and the Southeast Brazilian regions contributed to most publications, from areas that concentrate agricultural commodity complexes. Among the pesticides described in the studies, insecticides, herbicides, and fungicides were the most frequent. The articles reported multiple toxic effects, particularly in rural workers. The results obtained can be used to direct policies to reduce the use of pesticides, and to protect the health of the population.

Natterin-like depletion by CRISPR/Cas9 impairs zebrafish (Danio rerio) embryonic development

Background The Natterin protein family was first discovered in the venom of the medically significant fish Thalassophryne nattereri, and over the last decade natterin-like genes have been identified in various organisms, notably performing immune-related functions. Previous findings support natterin-like genes as effector defense molecules able to activate multiprotein complexes driving the host innate immune response, notably due to the pore-forming function of the aerolysin superfamily members. Herein, employing a combination of the CRISPR/Cas9 depletion system, phenotype-based screening, and morphometric methods, we evaluated the role of one family member, LOC795232, in the embryonic development of zebrafish since it might be implicated in multiple roles and characterization of the null mutant is central for analysis of gene activity. Results Multiple sequence alignment revealed that the candidate natterin-like has the highest similarity to zebrafish aep1, a putative and better characterized fish-specific defense molecule from the same family. Compared to other species, zebrafish have many natterin-like copies. Whole-mount in situ hybridization confirmed the knockout and mutant embryos exhibited epiboly delay, growth retardation, yolk sac and heart edema, absent or diminished swim bladder, spinal defects, small eyes and head, heart dysfunction, and behavioral impairment. As previously demonstrated, ribonucleoproteins composed of Cas9 and duplex guide RNAs are effective at inducing mutations in the F0 zebrafish. Conclusions The considerably high natterin-like copies in zebrafish compared to other species might be due to the teleost-specific whole genome duplication and followed by subfunctionalization or neofunctionalization. In the present work, we described some of the natterin-like features in the zebrafish development and infer that natterin-like proteins potentially contribute to the embryonary development and immune response.

The Natterin Proteins Diversity: A Review on Phylogeny, Structure, and Immune Function.

Since the first record of the five founder members of the group of Natterin proteins in the venom of the medically significant fish Thalassophryne nattereri, new sequences have been identified in other species. In this work, we performed a detailed screening using available genome databases across a wide range of species to identify sequence members of the Natterin group, sequence similarities, conserved domains, and evolutionary relationships. The high-throughput tools have enabled us to dramatically expand the number of members within this group of proteins, which has a remote origin (around 400 million years ago) and is spread across Eukarya organisms, even in plants and primitive Agnathans jawless fish. Overall, the survey resulted in 331 species presenting Natterin-like proteins, mainly fish, and 859 putative genes. Besides fish, the groups with more species included in our analysis were insects and birds. The number and variety of annotations increased the knowledge of the obtained sequences in detail, such as the conserved motif AGIP in the pore-forming loop involved in the transmembrane barrel insertion, allowing us to classify them as important constituents of the innate immune defense system as effector molecules activating immune cells by interacting with conserved intracellular signaling mechanisms in the hosts.

Heat-Labile Toxin from Enterotoxigenic Escherichia coli Causes Systemic Impairment in Zebrafish Model.

Heat-labile toxin I (LT-I), produced by strains of enterotoxigenic Escherichia coli (ETEC), causes profuse watery diarrhea in humans. Different in vitro and in vivo models have already elucidated the mechanism of action of this toxin; however, their use does not always allow for more specific studies on how the LT-I toxin acts in systemic tracts and intestinal cell lines. In the present work, zebrafish (Danio rerio) and human intestinal cells (Caco-2) were used as models to study the toxin LT-I. Caco-2 cells were used, in the 62nd passage, at different cell concentrations. LT-I was conjugated to FITC to visualize its transport in cells, as well as microinjected into the caudal vein of zebrafish larvae, in order to investigate its effects on survival, systemic traffic, and morphological formation. The internalization of LT-I was visualized in 3 × 104 Caco-2 cells, being associated with the cell membrane and nucleus. The systemic traffic of LT-I in zebrafish larvae showed its presence in the cardiac cavity, yolk, and regions of the intestine, as demonstrated by cardiac edema (100%), the absence of a swimming bladder (100%), and yolk edema (80%), in addition to growth limitation in the larvae, compared to the control group. There was a reduction in heart rate during the assessment of larval survival kinetics, demonstrating the cardiotoxic effect of LT-I. Thus, in this study, we provide essential new depictions of the features of LT-I.

Early preclinical screening using zebrafish (Danio rerio) reveals the safety of the candidate anti-inflammatory therapeutic agent TnP.

The patented anti-inflammatory peptide TnP had its effectiveness recently confirmed in vivo in a murine model of multiple sclerosis and asthma. In this work, the safety of the TnP was evaluated in investigative toxicology tests using zebrafish (Danio rerio) as a model. We conducted the OECD #236 test to investigate effects of the TnP on the survival, hatching performance, and morphological formation of zebrafish embryos. After determining these endpoints, morphometric analysis termination of locomotion eartbeat rate in zebrafish larvae were evaluated to identify adverse effects such as neurotoxicity and cardiotoxicity. The results highlight a wide therapeutic index for TnP with non-lethal and safe doses rom 1 nM to 10 µM, without causing neurotoxicity or cardiotoxic effect. The low frequencyf abnormalities by TnP was associated with high safety of the molecule and the developing embryo's ability to process and eliminate it. TnP crossed the blood-brain barrier without disturbing the normal architecture of forebrain, midbrain and hindbrain. Our data reinforce the importance of zebrafish as an accurate investigative toxicology model to assess acute toxicity as well as cardiotoxicity and neurotoxicity of molecules in the preclinical phase of development.