Selective visuoconstructional impairment following mild COVID-19 with inflammatory and neuroimaging correlation findings.

People recovered from COVID-19 may still present complications including respiratory and neurological sequelae. In other viral infections, cognitive impairment occurs due to brain damage or dysfunction caused by vascular lesions and inflammatory processes. Persistent cognitive impairment compromises daily activities and psychosocial adaptation. Some level of neurological and psychiatric consequences were expected and described in severe cases of COVID-19. However, it is debatable whether neuropsychiatric complications are related to COVID-19 or to unfoldings from a severe infection. Nevertheless, the majority of cases recorded worldwide were mild to moderate self-limited illness in non-hospitalized people. Thus, it is important to understand what are the implications of mild COVID-19, which is the largest and understudied pool of COVID-19 cases. We aimed to investigate adults at least four months after recovering from mild COVID-19, which were assessed by neuropsychological, ocular and neurological tests, immune markers assay, and by structural MRI and 18FDG-PET neuroimaging to shed light on putative brain changes and clinical correlations. In approximately one-quarter of mild-COVID-19 individuals, we detected a specific visuoconstructive deficit, which was associated with changes in molecular and structural brain imaging, and correlated with upregulation of peripheral immune markers. Our findings provide evidence of neuroinflammatory burden causing cognitive deficit, in an already large and growing fraction of the world population. While living with a multitude of mild COVID-19 cases, action is required for a more comprehensive assessment and follow-up of the cognitive impairment, allowing to better understand symptom persistence and the necessity of rehabilitation of the affected individuals.

Prevalence and characteristics of ESBL-producing Escherichia coli in clinically healthy pigs: implications for antibiotic resistance spread in livestock.

AIM: This study aimed to compare and characterize the resistance profile and the presence of extended-spectrum beta-lactamase (ESBL) related genes in Escherichia coli isolated from healthy finishing pigs fed with or without antibiotics in their diets. METHODS AND RESULTS: A total of 27 ceftiofur-resistant E. coli isolates were obtained from 96 healthy pigs. The antibiotic resistance profile was tested, and all 27 isolates were classified as multidrug-resistant (MDR). A high proportion of isolates were resistant to cephalosporins, ampicillin, ciprofloxacin, and tetracyclines. The ESBL production was observed in 85% of isolates by double-disc synergy test. The MDR-E. coli isolates harbored ESBL genes, such as blaTEM, blaCTX-M-1, blaCTX-M-2, and blaCTX-M-8,25. In addition, other antibiotics resistance genes (ARGs) were also detected, such as sul2, ant(3″)-I, tetA, and mcr-1. The mobilization of the blaCTX-M gene was confirmed for nine E. coli isolates by conjugation assays. The presence of blaCTX-M on mobile genetic elements in these isolates was demonstrated by Southern blot hybridization, and the resistance to cephalosporins was confirmed in the transconjugants. Our results indicate the prevalence of CTX-M-producing E. coli strains harboring mobile genetic elements in the normal microbiota of healthy pigs. CONCLUSIONS: These findings highlight the significance of ESBL genes as a global health concern in livestock and the potential spread of antimicrobial resistance to other members of the gastrointestinal tract microbiota.

Genotoxic and antiproliferative properties of Endopleura uchi bark aqueous extract.

The bark extract from Endopleura uchi has been widely used in traditional medicine to treat gynecological-related disorders, diabetes, and dyslipidemias albeit without scientific proof. In addition, E. uchi bark extract safety, especially regarding mutagenic activities, is not known. The aim of this study was to determine the chemical composition, antitumor, and toxicological parameters attributed to an E. uchi bark aqueous extract. The phytochemical constitution was assessed by colorimetric and chromatographic analyzes. The antiproliferative effect was determined using sulforhodamine B (SRB) assay using 4 cancer cell lines. Cytotoxic and genotoxic activities were assessed utilizing MTT and comet assays, respectively, while mutagenicity was determined through micronucleus and Salmonella/microsome assays. The chromatographic analysis detected predominantly the presence of gallic acid and isoquercitrin. The antiproliferative effect was more pronounced in human colon adenocarcinoma (HT-29) and human breast cancer (MCF-7) cell lines. In the MTT assay, the extract presented an IC50 = 39.1 µg/ml and exhibited genotoxic (comet assay) and mutagenic (micronucleus test) activities at 20 and 40 µg/ml in mouse fibroblast cell line (L929) and mutagenicity in the TA102 and TA97a strains in the absence of S9 mix. Data demonstrated that E. uchi bark possesses bioactive compounds which exert cytotoxic and genotoxic effects that might be associated with its antitumor potential. Therefore, E. uchi bark aqueous extract consumption needs to be approached with caution in therapeutic applications.

Developing and validating a 2D digital version of the Brazilian Children's anxiety questionnaire.

PURPOSE: This study aims to transpose the printed Brazilian Children's Anxiety Questionnaire (CAQ BR) into a 2D digital format, validate it with nurses and hospitalized children, and analyze the association between the printed and 2D digital format versions. DESIGN AND METHOD: This is a descriptive and multicentric study, conducted from 2021 to 2022 on working in pediatric care at two hospitals in Brazil. The nurses analyzed the printed and digital instruments and subsequently applied them to a child and proposed suggestions. A cutoff score of 0.80 on the content validity index was used; items that scored an average lower than the CVI in the study were adequate. Eighty children responded to the questionnaires sequentially according to the randomization table. A 90% agreement rate was used. RESULTS: The digital instrument was validated in content by 51 experts, with a CVI of 0.95. Face validation data for 80 children (mean age = 7.9 years) shows a 90% agreement rate. The intraclass correlation index for the general score was 0.87 and 95% CI (0.79-0.91), which shows good stability of the children's responses in both questionnaires. In addition, 59% (n = 47) of the children reported a preference for the digital questionnaire. CONCLUSIONS: The digital CAQ BR can be used as an audiovisual instrument by nurses when implementing the systematization of nursing care in pediatrics. PRACTICAL IMPLICATIONS: The digital 2D version was successfully applied and can be used in hospitals to measure children's self-reported anxiety.

Physical activity of adolescents and the urban environment of Brazilian capitals: National School Health Survey, 2015.

This study aimed to evaluate the practice of physical activity (PA) among adolescents and its association with characteristics of the urban environment of Brazilian capitals. Study with adolescents from the 26 Brazilian capitals and the Federal District participating in the National School Health Survey, 2015 edition. The association between regular practice of PA (≥300 minutes/week) and the dimensions of urban well-being (urban mobility, urban environmental conditions, urban housing conditions, urban collective services, and urban infrastructure) was examined using multilevel logistic regression. A total of 50,904 adolescents were evaluated, among which 20.7% were active. It was observed in the multiple model that adolescents who live in capitals with better urban environmental conditions, such as the presence of tree coverage, less open sewage, and less accumulated garbage around the houses, are more likely to be active (OR = 1.06; 95% CI:1.01;1.12). Adolescents who live in cities with less urban disorder are more likely to be active.

Serum soluble mediators as prognostic biomarkers for morbidity, disease outcome, and late-relapsing hepatitis in yellow fever patients.

This study described a soluble mediator storm in acute Yellow Fever/YF infection along the kinetics timeline towards convalescent disease. The analyses of the YF Viral RNAnemia, chemokines, cytokines, and growth factors were performed in YF patients at acute/(D1-15) and convalescent/(D16-315) phases. Patients with acute YF infection displayed a trimodal viremia profile spreading along D3, D6, and D8-14. A massive storm of mediators was observed in acute YF. Higher levels of mediators were observed in YF with higher morbidity scores, patients under intensive care, and those progressing to death than in YF patients who progress to late-relapsing hepatitis/L-Hep. A unimodal peak of biomarkers around D4-6 with a progressive decrease towards D181-315 was observed in non-L-Hep patients, while a bimodal pattern with a second peak around D61-90 was associated with L-Hep. This study provided a comprehensive landscape of evidence that distinct immune responses drive pathogenesis, disease progression, and L-Hep in YF patients.

45 Is the new 50: improving colon cancer screening rates.

PURPOSE OF REVIEW: The colonoscopy guidelines recently changed to begin screening at age 45. This review discusses the reasons for lowering the age, adenomatous polyp detection rates for patients 45-49, and to discover innovative health education campaigns aimed at younger patients. RECENT FINDINGS: There are currently approximately 20 million Americans between the age of 45-49 who will need to be screened by gastroenterologists. The prevalence of overall and advanced colorectal neoplasia on screening colonoscopy for average-risk individuals younger than 50 years is 14% and 2%. An important 2022 study using the GI Quality Improvement Consortium Registry demonstrated that patients aged 45-49 had an overall adenoma detection rate of >25%. SUMMARY: Health education campaigns need to immediately target 20 million Americans to begin colorectal cancer screening. Additional research should focus on whether there are sex differences for adenoma detection rates among patients aged 46-49. Innovative health education campaigns such as "Tune It Up: A Concert To Raise Colorectal Cancer" organized by the American College of Gastroenterology are educating younger patients to begin colorectal screening by combining concerts and health communication.

Dry tobacco leaves: an in vivo and in silico approach to the consequences of occupational exposure.

Exposure of tobacco workers handling dried tobacco leaves has been linked to an increased risk of toxicity and respiratory illness due to the presence of nicotine and other chemicals. This study aimed to evaluate the DNA damage caused by the exposure of tobacco growers during the dry leaf classification process and the relation to cellular mechanisms. A total of 86 individuals participated in the study, divided into a group exposed to dry tobacco (n = 44) and a control group (n = 42). Genotoxicity was evaluated using the alkaline comet assay and lymphocyte micronucleus (MN) assay (CBMN-Cyt), and measurement of telomere length. The levels of oxidative and nitrosative stress were evaluated through the formation of thiobarbituric acid reactive species, and nitric oxide levels, respectively. The inorganic elements were measured in the samples using particle-induced X-ray emission method. The combination of variables was demonstrated through principal component analysis and the interactions were expanded through systems biology. Comet assay, MN, death cells, thiobarbituric acid reactive species, and nitrosative stress showed a significant increase for all exposed groups in relation to the control. Telomere length showed a significant decrease for exposed women and total exposed group in relation to men and control groups, respectively. Bromine (Br) and rubidium (Rb) in the exposed group presented higher levels than control groups. Correlations between nitrate and apoptosis; Br and MN and necrosis; and Rb and telomeres; besides age and DNA damage and death cells were observed. The systems biology analysis demonstrated that tobacco elements can increase the nuclear translocation of NFKB dimers inducing HDAC2 expression, which, associated with BRCA1 protein, can potentially repress transcription of genes that promote DNA repair. Dry tobacco workers exposed to dry leaves and their different agents showed DNA damage by different mechanisms, including redox imbalance.

Selection of Antarctic yeasts as gray mold biocontrol agents in strawberry.

The postharvest disease popularly known as gray mold is considered one of the most limiting factors strawberry fruit production. The most effective way to control this disease is still the use of chemical fungicides. However, other alternative sources of control are being explored. Among these, psychrophilic yeasts adapted to extreme conditions, such as those found in the Antarctic region, may have great potential for use as biocontrol agents. Thus, the present study aimed to select psychrotolerant yeasts obtained from Antarctic region and to evaluate their potential for biocontrol under gray mold, caused by Botrytis cinerea in strawberries stored at low temperature. For this, 20 potential antagonist yeasts were evaluated in vitro (thermotolerance and enzymatic) assays. Debaryomyces hansenii, Rhodotorula mucilaginosa and Dioszegia hungarica were selected for growing in strawberry juice. However, only D. hansenii was selected for in vivo studies and showed a reduction in the incidence of gray mold by 82% for the tests performed on injury and 86% for the tests on non-injured fruits treated by immersion bath. Thus, demonstrating that the selection of this cold-adapted Antarctic yeast can be a promising strategy as a biocontrol agent used to curb the development of gray mold in strawberry fruits.

Exposure to coal mining can lead to imbalanced levels of inorganic elements and DNA damage in individuals living near open-pit mining sites.

Coal mining activities are considered harmful to living organisms. These activities release compounds to the environment, such as polycyclic aromatic hydrocarbons (PAHs), metals, and oxides, which can cause oxidative damage to DNA. In this study, we compared the DNA damage and the chemical composition of peripherical blood of 150 individuals exposed to coal mining residues and 120 non-exposed individuals. Analysis of coal particles revealed the presence of elements such as copper (Cu), aluminum (Al), chrome (Cr), silicon (Si) and iron (Fe). The exposed individuals in our study had significant concentrations of Al, sulfur (S), Cr, Fe, and Cu in their blood, as well as hypokalemia. Results from the enzyme-modified comet assay (FPG enzyme) suggest that exposure to coal mining residues caused oxidative DNA damage, particularly purine damage. Furthermore, particles with a diameter of <2.5 µm indicate that direct inhalation could promote these physiological alterations. Finally, a systems biology analysis was performed to investigate the effects of these elements on DNA damage and oxidative stress pathways. Interestingly, Cu, Cr, Fe, and K are key nodes that intensely modulate these pathways. Our results suggest that understanding the imbalance of inorganic elements caused by exposure to coal mining residues is crucial to understanding their effect on human health.

Antimicrobial Resistance Profiles of Multidrug-Resistant Enterobacteria Isolated from Feces of Weaned Piglets.

Nosocomial infections caused by multidrug-resistant enterobacteria have become a major challenge in global public health. Previous studies have indicated that use of antibiotics in livestock production chains is linked to the rising threat of antibiotic resistance in humans. In this study, we aimed to evaluate the distribution of genes encoding resistance to tetracycline, ß-lactams, and colistin in multidrug-resistant enterobacteria isolated from feces of weaned pigs. Ninety-four enterobacteria isolates were submitted to antibiotic susceptibility test by minimum inhibitory concentration (MIC). In addition, we performed conjugation experiments to verify if plasmid-bearing isolates containing the mcr-1 gene could transfer their resistance determinant to a colistin-sensitive recipient strain. Our results demonstrated a positive association between the detection of antibiotic resistance genes in enterobacteria and the phenotypic resistance profiles of the bacterial isolates. At least one of the extended-spectrum ß-lactamases (ESBL) genes (blaCTX-M, blaTEM, or bla SHV) and tetA was found among most bacterial genera analyzed. In addition, results revealed that the mcr-1 gene can be transferred from E. coli UFV-627 isolate to an F- recipient (Escherichia coli K12) by conjugation. Our findings support the hypothesis that swine represents an important reservoir of antibiotic resistance genes and suggest that horizontal transfer mechanisms (e.g., conjugation) may mediate the spread of these genes in the swine gastrointestinal tract.

[Mapping public health training in Latin America: perspectives for training institutionsMapeamento da formação em saúde pública na América Latina: perspectivas para as instituições formadoras]. / Mapeo de la formación en salud pública en América Latina: perspectivas para las instituciones formadoras.

Objective: Map the public health training courses and programs offered in Latin America, and identify regional training strategies and competencies developed in health workers. Methods: An internet search was conducted to identify public health training courses and programs offered by Latin American institutions. The following data were collected: name, country, and province/state of the training institution; course name; type of institution; educational level; modality; accreditation; year first offered; periodicity; and contact information. The programs and curricula on offer were analyzed by training level using descriptive content analysis, and the main competencies developed were identified. Results: The mapping identified 2 296 public health training opportunities in all Latin American subregions, distributed across 29 of the Region's 33 countries; these were fairly heterogeneous, both conceptually and programmatically, with uneven geographical distribution within and between countries. In the analysis of curricula and programmatic contents, a need for greater linkage with essential public health functions was detected. Conclusion: It is necessary to adapt the competencies and skills developed by the courses and programs to the demands of users of the regional health services, programs, and systems in order to achieve programs aimed at tackling the socio-environmental determinants of health and the production and reproduction of inequalities.

Objetivo: Mapear os cursos e programas de formação em saúde pública oferecidos na América Latina e identificar estratégias de formação e competências desenvolvidas na formação regional de profissionais de saúde pública. Métodos: Foi realizada uma busca na internet para identificar cursos e programas de formação em saúde pública oferecidos por instituições latino-americanas. Foram coletados os seguintes dados: nome, país e estado ou província da instituição formadora; nome do curso; característica da instituição; nível de formação; modalidade; acreditação; ano da primeira turma; regularidade e detalhes de contato. Em seguida, os programas e currículos oferecidos foram analisados por nível de formação, por meio da técnica descritiva de análise de conteúdo, e foram identificadas as principais competências desenvolvidas. Resultados: O mapeamento permitiu identificar 2 296 ofertas de formação em saúde pública em todas as sub-regiões da América Latina, distribuídas em 29 dos 33 países da Região. As ofertas identificadas foram bastante heterogêneas, tanto do ponto de vista conceitual como programático, e com uma distribuição geográfica desproporcional nos países e entre as sub-regiões. A análise dos currículos e conteúdos programáticos detectou a necessidade de um maior vínculo com as funções essenciais da saúde pública. Conclusão: Observou-se a necessidade de adequar as competências e habilidades desenvolvidas pelos cursos e programas às demandas dos usuários dos serviços, programas e sistemas regionais de saúde, a fim de concretizar programas voltados para o enfrentamento dos processos de determinação socioambiental da saúde e de produção e reprodução de desigualdades.

Sex differences and predictors of completion of a 6-month exercise-based cardiac rehabilitation program in 1,536 people following stroke.

OBJECTIVE: To retrospectively examine sex-differences and predictors of completion in consecutively-referred patients to a 6-month exercise-based cardiac rehabilitation program (CRP) from 2006 to 2017. MATERIALS/METHODS: People with hemiplegic gait participated in stroke-adapted-CRP; otherwise, traditional-CRP. Reasons for non-completion were ascertained by interview. Regression-analyses were conducted to determine non-completion in all patients and women and men separately. RESULTS: There were 1536 patients (30.3% women), mean age 64.5 ± 12.5 with 23% initiating the stroke-adapted-CRP. Overall, 75.1% completed the CRP (87.3% stroke-adapted-CRP vs 71.5% traditional-CRP; p < .001). There was no difference in completion between women and men (74.5% vs 75.4%; p=0.7), or in attendance to pre-scheduled sessions (p=0.6) or reasons for non-completion (p > .05, all). The only sex difference in completion by age (decade) occurred in those <41 years (59% women vs 85% men; p=.02). Baseline predictors of non-completion among all patients included not being enrolled in the stroke-adapted-CRP, lower V̇O2peak, smoking, diabetes (prescribed insulin) and depression but not sex (p=.5) or age (p=.15). Unique predictors in women vs men were younger age, lower V̇O2peak, smoking, diabetes (prescribed insulin), depression, and cancer diagnoses. Unique to men was having >1 stroke and diabetes (any anti-diabetes medication). The strongest predictor of non-completion among all models was not being enrolled in stroke-adapted-CRP. CONCLUSIONS: While there were no sex-differences in adherence to the CRP, women and men have mostly unique predictors of non-completion. Younger women are at greatest risk for non-completion. Practitioners should provide sex-specific, tailored strategies for enhancing completion with a focus on younger women and offering a stroke-adapted-CRP with close attention to those with diabetes.

The dangerous link between coal dust exposure and DNA damage: unraveling the role of some of the chemical agents and oxidative stress.

Exposure to coal mining dust poses a substantial health hazard to individuals due to the complex mixture of components released during the extraction process. This study aimed to assess the oxidative potential of residual coal mining dust on human lymphocyte DNA and telomeres and to perform a chemical characterization of coal dust and urine samples. The study included 150 individuals exposed to coal dust for over ten years, along with 120 control individuals. The results revealed significantly higher levels of DNA damage in the exposed group, as indicated by the standard comet assay, and oxidative damage, as determined by the FPG-modified comet assay. Moreover, the exposed individuals exhibited significantly shorter telomeres compared to the control group, and a significant correlation was found between telomere length and oxidative DNA damage. Using the PIXE method on urine samples, significantly higher concentrations of sodium (Na), phosphorus (P), sulfur (S), chlorine (Cl), potassium (K), iron (Fe), zinc (Zn), and bromine (Br) were observed in the exposed group compared to the control group. Furthermore, men showed shorter telomeres, greater DNA damage, and higher concentrations of nickel (Ni), calcium (Ca), and chromium (Cr) compared to exposed women. Additionally, the study characterized the particles released into the environment through GC-MS analysis, identifying several compounds, including polycyclic aromatic hydrocarbons (PAHs) such as fluoranthene, naphthalene, anthracene, 7H-benzo[c]fluorene, phenanthrene, pyrene, benz[a]anthracene, chrysene, and some alkyl derivatives. These findings underscore the significant health risks associated with exposure to coal mining dust, emphasizing the importance of further research and the implementation of regulatory measures to safeguard the health of individuals in affected populations.

Monitoring Emerging Human Immunodeficiency Virus Drug Resistance in Sub-Saharan Africa in the Era of Dolutegravir.

Dolutegravir-based regimens are now standard of care for human immunodeficiency virus treatment for millions of people around sub-Saharan Africa. To ensure its continued efficacy, monitoring of emerging drug resistance that inform a treatment strategy among those failing is crucial. In this report, we outline the US President's Emergency Plan for AIDS Relief to leverage viral load infrastructure to implement effective drug resistance surveillance in the countries it supports.

Epidemiologic, Immunologic, and Virus Characteristics in Patients With Paired Severe Acute Respiratory Syndrome Coronavirus 2 Serology and Reverse-Transcription Polymerase Chain Reaction Testing.

BACKGROUND: The natural history and clinical progression of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections can be better understood using combined serological and reverse-transcription polymerase chain reaction (RT-PCR) testing. METHODS: Nasopharyngeal swabs and serum were collected at a single time-point from patients at an urban, public hospital during August-November 2020 and tested for SARS-CoV-2 using RT-PCR, viral culture, and anti-spike pan-immunoglobulin antibody testing. Participant demographics and symptoms were collected through interview. The χ 2 and Fisher exact tests were used to identify associations between RT-PCR and serology results with presence of viable virus and frequency of symptoms. RESULTS: Among 592 participants, 129 (21.8%) had evidence of SARS-CoV-2 infection by RT-PCR or serology. Presence of SARS-CoV-2 antibodies was strongly associated with lack of viable virus (P = .016). COVID-19 symptom frequency was similar for patients testing RT-PCR positive/seronegative and patients testing RT-PCR positive/seropositive. Patients testing RT-PCR positive/seronegative reported headaches, fatigue, diarrhea, and vomiting at rates not statistically significantly different from those testing RT-PCR negative/seropositive. CONCLUSIONS: While patients testing SARS-CoV-2 seropositive were unlikely to test positive for viable virus and were therefore at low risk for forward transmission, coronavirus disease 2019 (COVID-19) symptoms were common. Paired SARS-CoV-2 RT-PCR and antibody testing provides more nuanced understanding of patients' COVID-19 status.

Ventrolateral periaqueductal gray matter integrative system of defense and antinociception.

Defensive responses are neurophysiological processes crucial for survival during threatening situations. Defensive immobility is a common adaptive response, in rodents, elaborated by ventrolateral periaqueductal gray matter (vlPAG) when threat is unavoidable. It is associated with somatosensory and autonomic reactions such as alteration in the sensation of pain and rate of respiration. In this study, defensive immobility was assessed by chemical stimulation of vlPAG with different doses of NMDA (0.1, 0.3, and 0.6 nmol). After elicitation of defensive immobility, antinociceptive and respiratory response tests were also performed. Results revealed that defensive immobility was followed by a decrease in the nociceptive perception. Furthermore, the lowest dose of NMDA induced antinociceptive response without eliciting defensive immobility. During defensive immobility, respiratory responses were also disturbed. Interestingly, respiratory rate was increased and interspersed with prolonged expiratory phase of breathing. These findings suggest that vlPAG integrates three different defensive behavioral responses, contributing to the most effective defensive strategies during threatening situations.

Cluster of SARS-CoV-2 Gamma Variant Infections, Parintins, Brazil, March 2021.

High case counts after the Gamma (P. 1) variant of severe acute respiratory syndrome coronavirus 2 emerged in Brazil raised concerns that previously infected persons might become reinfected. Investigation of a cluster of coronavirus disease cases in Parintins, in the Brazilian Amazon, suggested household transmission but did not identify high rates of reinfection.

A Genetically Modified Anti-Plasmodium Bacterium Is Harmless to the Foragers of the Stingless Bee Partamona helleri.

Paratransgenesis consists of genetically engineering an insect symbiont to control vector-borne diseases. Biosafety assessments are a prerequisite for the use of genetically modified organisms (GMOs). Assessments rely on the measurement of the possible impacts of GMOs on different organisms, including beneficial organisms, such as pollinators. The bacterium Serratia AS1 has been genetically modified to express anti-Plasmodium effector proteins and does not impose a fitness cost on mosquitoes that carry it. In the present study, we assessed the impact of this bacterium on the native bee Partamona helleri (Meliponini), an ecologically important species in Brazil. Serratia eGFP AS1 (recombinant strain) or a wild strain of Serratia marcescens were suspended in a sucrose solution and fed to foragers, followed by measurements of survival, feeding rate, and behavior (walking and flying). These bacteria did not change any of the variables measured at 24, 72, and 144 h after the onset of the experiment. Recombinant and wild bacteria were detected in the homogenates of digestive tract during the 144 h period analyzed, but their numbers decreased with time. The recombinant strain was detected in the midgut at 24 h and in the hindgut at 72 h and 144 h after the onset of the experiment under the fluorescent microscope. As reported for mosquitoes, Serratia eGFP AS1 did not compromise the foragers of P. helleri, an ecologically relevant bee.

Selection of Multidrug-Resistant Enterobacteria in Weaned Pigs and Its Association With In-feed Subtherapeutic Combination of Colistin and Tylosin.

In-feed antibiotics are administered to piglets to improve performance and production efficiency. However, the use of growth promoters in the swine industry can select for multidrug-resistant (MDR) bacteria. Here, we evaluate the resistance profile of enterobacteria isolated from fecal samples of weaned pigs (21-35 days) fed or not with antibiotics (colistin and tylosin) and investigated the piglets gut microbiota in both groups. Six hundred and eighteen bacterial cultures were isolated from the control group (CON; n = 384) and antibiotic-fed pigs (ATB; n = 234). All isolates were tested for resistance to 12 antibiotics belonging to six distinct antibiotic classes. Isolates were highly resistant to ampicillin (90%; n = 553), amoxicillin (85%; n = 525), and tetracycline (81%; n = 498). A significant increase (P < 0.05) in resistance to cephalexin, kanamycin, doxycycline, and colistin was observed for bacteria from the ATB group. Piglets allocated in the ATB and CON groups shared similar intestinal microbiota, as revealed by alpha- and beta-diversity analyses. Our findings demonstrate that colistin and tylosin contribute to select MDR enterobacteria in weaned piglets. The high frequency of antibiotic resistance among isolates from the CON group suggests that environmental sources (e.g., fecal contents, aerosols, soil, water, food) also represent a potential reservoir of multidrug-resistant enterobacteria in pig production systems.