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1.
Antibiotics (Basel) ; 13(5)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38786123

RESUMO

Various genetic elements, including integrons, are known to contribute to the development of antimicrobial resistance. Class 1 integrons have been identified in E. coli isolates and are associated with multidrug resistance in countries of the Andean Community. However, detailed information on the gene cassettes located on the variable regions of integrons is lacking. Here, we investigated the presence and diversity of class 1 integrons, using an in silico approach, in 2533 whole-genome sequences obtained from EnteroBase. IntFinder v1.0 revealed that almost one-third of isolates contained these platforms. Integron-bearing isolates were associated with environmental, food, human, and animal origins reported from all countries under scrutiny. Moreover, they were identified in clones known for their pathogenicity or multidrug resistance. Integrons carried cassettes associated with aminoglycoside (aadA), trimethoprim (dfrA), cephalosporin (blaOXA; blaDHA), and fluoroquinolone (aac(6')-Ib-cr; qnrB) resistance. These platforms showed higher diversity and larger numbers than previously reported. Moreover, integrons carrying more than three cassettes in their variable regions were determined. Monitoring the prevalence and diversity of genetic elements is necessary for recognizing emergent patterns of resistance in pathogenic bacteria, especially in countries where various factors are recognized to favor the selection of resistant microorganisms.

2.
Biol Res ; 57(1): 17, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38664786

RESUMO

BACKGROUND: Disseminated neoplasia (DN) is a proliferative cell disorder of the circulatory system of bivalve mollusks. The disease is transmitted between individuals and can also be induced by external chemical agents such as bromodeoxyuridine. In Mya arenaria, we have cloned and characterized an LTR-retrotransposon named Steamer. Steamer mRNA levels and gene copy number correlates with DN and can be used as a marker of the disease. So far, the only mollusk where a retrotransposon expression relates to DN is Mya arenaria. On the other hand, it has been reported that the Chilean blue mussel Mytilus chilensis can also suffers DN. Our aim was to identify retrotransposons in Mytilus chilensis and to study their expression levels in the context of disseminated neoplasia. RESULTS: Here we show that 7.1% of individuals collected in August 2018, from two farming areas, presents morphological characteristics described in DN. Using Steamer sequence to interrogate the transcriptome of M. chilensis we found two putative retrotransposons, named Steamer-like elements (MchSLEs). MchSLEs are present in the genome of M. chilensis and MchSLE1 is indeed an LTR-retrotransposon. Neither expression, nor copy number of the reported MchSLEs correlate with DN status but both are expressed at different levels among individual animals. We also report that in cultured M. chilensis haemocytes MchSLEs1 expression can be induced by bromodeoxyuridine. CONCLUSIONS: We conclude that SLEs present in Mytilus chilensis are differentially expressed among individuals and do not correlate with disseminated neoplasia. Treatment of haemocytes with a stressor like bromodeoxyuridine induces expression of MchSLE1 suggesting that in Mytilus chilensis environmental stressors can induce activation of LTR-retrotransposon.


Assuntos
Mytilus , Retroelementos , Animais , Mytilus/genética , Retroelementos/genética , Chile
3.
Biol. Res ; 572024.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1564032

RESUMO

Background Disseminated neoplasia (DN) is a proliferative cell disorder of the circulatory system of bivalve mollusks. The disease is transmitted between individuals and can also be induced by external chemical agents such as bromodeoxyuridine. In Mya arenaria, we have cloned and characterized an LTR-retrotransposon named Steamer. Steamer mRNA levels and gene copy number correlates with DN and can be used as a marker of the disease. So far, the only mollusk where a retrotransposon expression relates to DN is Mya arenaria. On the other hand, it has been reported that the Chilean blue mussel Mytilus chilensis can also suffers DN. Our aim was to identify retrotransposons in Mytilus chilensis and to study their expression levels in the context of disseminated neoplasia. Results Here we show that 7.1% of individuals collected in August 2018, from two farming areas, presents morphological characteristics described in DN. Using Steamer sequence to interrogate the transcriptome ofM. chilensis we found two putative retrotransposons, named Steamer-like elements (MchSLEs). MchSLEs are present in the genome of M. chilensis and MchSLE1 is indeed an LTR-retrotransposon. Neither expression, nor copy number of the reported MchSLEs correlate with DN status but both are expressed at different levels among individual animals. We also report that in cultured M. chilensis haemocytes MchSLEs1 expression can be induced by bromodeoxyuridine. Conclusions We conclude that SLEs present in Mytilus chilensis are differentially expressed among individuals and do not correlate with disseminated neoplasia. Treatment of haemocytes with a stressor like bromodeoxyuridine induces expression of MchSLE1 suggesting that in Mytilus chilensis environmental stressors can induce activation of LTR-retrotransposon.

4.
J Appl Microbiol ; 134(11)2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37974051

RESUMO

AIMS: This study aimed to examine antibiotic resistance and the epidemiology of extended-spectrum ß-lactamases (ESBL)-producing Escherichia coli associated with bloodstream infections over a period of 10 years. METHODS AND RESULTS: Isolates were collected from January 2009 to December 2019 and those testing for E. coli were included. Antibiotic susceptibility was tested using the VITEK® system. Selected isolates were further characterized by amplification of marker genes (virulence traits, phylogroups, and sequence types). A total of 166 ESBL-producing E. coli were recovered. The blaCTX-M-15 allele was the most abundant. Most of the isolates were resistant to ceftriaxone, cefepime, ceftazidime, ampicillin/sulbactam, piperacillin/tazobactam, and ciprofloxacin. No resistance to carbapenems was registered. More than 80% of bacteria were classified as extraintestinal pathogenic E. coli (ExPEC), and the combination of virulence traits:papA-papC-kpsMII-uitA was the most common. Phylogroup B2 was the most prevalent, and bacteria predominantly belonged to ST131. CONCLUSIONS: There was an increase in the ExPEC ESBL-E coli in bloodstream infections and the relationship between the isolates found in these infections during these 10 years.


Assuntos
Infecções por Escherichia coli , Escherichia coli Extraintestinal Patogênica , Sepse , Humanos , Escherichia coli , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Equador/epidemiologia , beta-Lactamases/genética , Sepse/microbiologia , Antibacterianos/farmacologia
5.
Rev Med Chil ; 151(1): 15-22, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37906742

RESUMO

BACKGROUND: Patients with Coronavirus Disease 2019 (COVID-19) frequently experience a hyperinflammatory syndrome leading to unfavorable outcomes. This condition resembles Secondary Hemophagocytic Lymphohistiocytosis (sHLH) described in neoplastic, rheumatic and other infectious diseases. A scoring system (HScore) that evaluates underlying immunosuppression, temperature, organomegaly, cytopenias, ferritin, triglycerides, fibrinogen and AST was validated for sHLH, and recently proposed to evaluate hyperinflammation in COVID-19. AIM: To assess the presence of sHLH among patients with COVID-19 admitted for hospitalization and to evaluate Hscore as a prognostic tool for poor outcomes. MATERIAL AND METHODS: One hundred forty-three patients aged 21-100 years (64% males) admitted because of COVID-19 were enrolled in a prospective study. HScore was calculated within 72 hours admission. The incidence of sHLH during hospitalization was evaluated. Additionally, the relationship between a HScore ≥ 130 points and either the requirement of mechanical ventilation or 60-days mortality was explored. RESULTS: The median HScore was 96 (33-169). A SHLH was diagnosed in one patient (incidence 0.7%), whose HScore was 169. After adjusting for age, sex, comorbidities and obesity, HScore ≥ 130 was independently associated with the composite clinical outcome (Hazard rartio 2.13, p = 0.022). CONCLUSIONS: sHLH is not frequent among COVID-19 patients. HScore can be useful to predict the risk for poor outcomes.


Assuntos
COVID-19 , Linfo-Histiocitose Hemofagocítica , Masculino , Humanos , Feminino , COVID-19/complicações , Estudos Prospectivos , Linfo-Histiocitose Hemofagocítica/etiologia , Comorbidade , Hospitalização
6.
Microorganisms ; 11(8)2023 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-37630504

RESUMO

The implementation of government regulations on antibiotic use, along with the public's concern for drug resistance, has strengthened interest in developing alternatives not only aimed at preserving animal production but also at reducing the effects of pathogenic infections. Probiotics, in particular, are considered microorganisms that induce health benefits in the host after consumption of adequate amounts; they have been established as a potential strategy for improving growth, especially by stimulating intestinal homeostasis. Probiotics are commonly associated with lactic acid bacteria, and Limosilactobacillus fermentum is a well-studied species recognized for its favorable characteristics, including adhesion to epithelial cells, production of antimicrobial compounds, and activation of receptors that prompt the transcription of immune-associated genes. Recently, this species has been used in animal production. Different studies have shown that the application of L. fermentum strains not only improves the intestinal ecosystem but also reduces the effects caused by potentially pathogenic microorganisms. These studies have also revealed key insights into the mechanisms behind the actions exerted by this probiotic. In this manuscript, we aim to provide a concise overview of the effects of L. fermentum administration on broiler chicken health and performance.

7.
Microorganisms ; 11(2)2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36838221

RESUMO

There are no studies reporting the effects of Salmonella enterica subsp. enterica serovar Infantis (S. Infantis) on intestinal architecture and immunoglobulin serum levels in chickens. Here, we measured these parameters and hypothesized whether probiotic administration could modulate the observed outcomes. Two-hundred 1-day-old COBB 500 male chicks were allocated into four groups: (I) the control, (II) the group treated with L. fermentum, (III) the group exposed to S. Infantis, and (IV) the group inoculated with both bacteria. At 11 days post infection, blood was gathered from animals which were then euthanized, and samples from the small intestine were collected. Intestinal conditions, as well as IgA and IgM serum levels, were assessed. S. Infantis reduced villus-height-to-crypt-depth (VH:CD) ratios in duodenal, jejunal, and ileal sections compared to control conditions, although no differences were found regarding the number of goblet cells, muc-2 expression, and immunoglobulin concentration. L. fermentum improved intestinal measurements compared to the control; this effect was also evidenced in birds infected with S. Infantis. IgM serum levels augmented in response to the probiotic in infected animals. Certainly, the application of L. fermentum elicited positive outcomes in S. Infantis-challenged chickens and thus must be considered for developing novel treatments designed to reduce unwanted infections.

8.
Rev. méd. Chile ; 151(1): 15-22, feb. 2023. tab
Artigo em Inglês | LILACS | ID: biblio-1515413

RESUMO

BACKGROUND: Patients with Coronavirus Disease 2019 (COVID-19) frequently experience a hyperinflammatory syndrome leading to unfavorable outcomes. This condition resembles Secondary Hemophagocytic Lymphohistiocytosis (sHLH) described in neoplastic, rheumatic and other infectious diseases. A scoring system (HScore) that evaluates underlying immunosuppression, temperature, organomegaly, cytopenias, ferritin, triglycerides, fibrinogen and AST was validated for sHLH, and recently proposed to evaluate hyperinflammation in COVID-19. AIM: To assess the presence of sHLH among patients with COVID-19 admitted for hospitalization and to evaluate Hscore as a prognostic tool for poor outcomes. MATERIAL AND METHODS: One hundred forty-three patients aged 21-100 years (64% males) admitted because of COVID-19 were enrolled in a prospective study. HScore was calculated within 72 hours admission. The incidence of sHLH during hospitalization was evaluated. Additionally, the relationship between a HScore ≥ 130 points and either the requirement of mechanical ventilation or 60-days mortality was explored. RESULTS: The median HScore was 96 (33-169). A SHLH was diagnosed in one patient (incidence 0.7%), whose HScore was 169. After adjusting for age, sex, comorbidities and obesity, HScore ≥ 130 was independently associated with the composite clinical outcome (Hazard rartio 2.13, p = 0.022). CONCLUSIONS: sHLH is not frequent among COVID-19 patients. HScore can be useful to predict the risk for poor outcomes.


ANTECEDENTES: Los pacientes con Enfermedad por Coronavirus 2019 (COVID-19), experimentan frecuentemente un síndrome hiperinflamatorio que lleva a resultados desfavorables. Esta situación se asemeja al Síndrome Hemofagocítico Secundario (sHLH) descrito en enfermedades neoplásicas, reumatológicas y por otros agentes infecciosos. Un sistema simple de puntaje (HScore) que evalúa inmunosupresión, temperatura organomegalia, citopenias, ferritina, triglicéridos, fibrinógeno y AST ha sido validado para el diagnóstico de sHLH y ha sido propuesto recientemente para evaluar la hiperinflamación en COVID-19. OBJETIVO: Medir la frecuencia de sHLH entre pacientes con COVID-19 hospitalizados, y evaluar a HScore como una herramienta pronóstica. MATERIAL Y MÉTODOS: Ciento cuarenta y tres pacientes de 21 a 100 años (64% hombres) fueron ingresados en este estudio de cohorte prospectivo, unicéntrico. Se calculó HScore dentro de las primeras 72 horas desde el ingreso, y se midió la incidencia de sHLH durante la hospitalización. Adicionalmente, se evaluó la relación entre HScore ≥ 130 puntos y un desenlace compuesto de ventilación mecánica o muerte a los 60 días. RESULTADOS: La mediana de HScore fue 96 (33-169) puntos. Un paciente fue diagnosticado con sHLH (incidencia 0,7%). Luego de ajustar por edad, sexo, comorbilidades y obesidad, un HScore ≥ 130 se asoció de manera independiente con el desenlace compuesto. CONCLUSIONES: El sHLH no es frecuente en los pacientes con COVID-19. El uso de HScore puede ser útil para predecir el riesgo de desenlaces clínicos desfavorables.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Adulto Jovem , Linfo-Histiocitose Hemofagocítica/etiologia , COVID-19/complicações , Prognóstico , Comorbidade , Estudos Prospectivos , Hospitalização
9.
Sci Total Environ ; 860: 160500, 2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36435250

RESUMO

Inter-basin water transfer projects (IBTs) have significantly increased in number in recent decades due to the unremitting need to solve the problem of global water imbalance. However, given the complex challenges inherent in implementing and maintaining IBTs, there is a need to characterize the multi-faceted aspects of sustainability (or unsustainability) that result from these megaprojects. Through a systematic review of the literature, we sought to identify and characterize the positive and negative impacts that most often influence the sustainability of IBTs, focusing on impacts within the environmental, social, and economic pillars of sustainability. Based on an eligibility criterion, the systematic review selected 68 documents out of an initial total of 1567 for information quality analysis and content evaluation. The qualitative coding of the documents allowed us to characterize the landscape of impacts that result from IBTs across the three pillars of sustainability. The study findings revealed that the most frequently coded positive impacts related to the environmental pillar of sustainability, while the most frequently coded negative impacts related to both social and environmental pillars. In addition, the most frequently coded positive impact overall related to the economic benefits generated by the IBTs. Through a critical analysis of the study findings, we provide an assessment of future IBTs with a focus on the UN sustainable development goals.


Assuntos
Conservação dos Recursos Naturais , Água , Desenvolvimento Sustentável
10.
Vet Sci ; 9(9)2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-36136705

RESUMO

Salmonella enterica serovars cause infections in humans. S. enterica subsp. enterica serovar Infantis is considered relevant and is commonly reported in poultry products. Evaluating innovative approaches for resisting colonization in animals could contribute to the goal of reducing potential human infections. Microalgae represent a source of molecules associated with performance and health improvement in chickens. Tetraselmis chuii synthesizes fermentable polysaccharides as part of their cell wall content; these sugars are known for influencing caecal bacterial diversity. We hypothesized if its dietary administration could exert a positive effect on caecal microbiota in favor of a reduced S. Infantis load. A total of 72 one-day-old broiler chickens (COBB 500) were randomly allocated into three groups: a control, a group infected with bacteria (day 4), and a group challenged with S. Infantis but fed a microalgae-based diet. Caecal samples (n = 8) were collected two days post-infection. A PMAxxTM-based qPCR approach was developed to assess differences regarding bacterial viable load between groups. The inclusion of the microalga did not modify S. Infantis content, although the assay proved to be efficient, sensitive, and repeatable. The utilized scheme could serve as a foundation for developing novel PCR-based methodologies for estimating Salmonella colonization.

11.
Antibiotics (Basel) ; 11(2)2022 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-35203800

RESUMO

The inappropriate use of antibiotics leads to antibiotic resistance, which reduces their efficacy. The education of undergraduates is likely to influence their practices. Assessing awareness is critical in the general effort to confront the spread of antibiotic resistance. This cross-sectional investigation was carried out using the questionnaire "Antibiotic resistance: Multi-country public awareness" developed by the World Health Organization. Students from different backgrounds at the Central University participated in the study (n = 733). The survey comprised five sections: demographics, knowledge, usage, sources of information, and attitudes. The rate of correct answers was 64.88%; differences were detected between programs of study (p < 0.001); effect size analysis showed that these differences cannot be considered large. Individuals from applied sciences scored higher than their counterparts from social studies. Mostly, interviewees were knowledgeable about usage, but mistakenly associated antibiotics with conditions such as cold/flu or viral illnesses; also, they associated antibiotic resistance with the patient and not with bacteria. Despite these misconceptions, positive attitudes were registered overall, and students generally adhered to common practices. They cited doctors/nurses and teachers as sources of information. As a consequence, it is recommended to develop courses that address deficient knowledge regarding antibiotic resistance, especially for individuals affiliated to social disciplines.

12.
Rev. colomb. radiol ; 33(2): 5778-5781, jun 2022. imag
Artigo em Inglês, Espanhol | LILACS, COLNAL | ID: biblio-1435010

RESUMO

La toxoplasmosis cerebral o neurotoxoplasmosis es una de las infecciones por agentes oportunistas más frecuentes en pacientes infectados por virus de inmunodeficiencia humana (VIH) y se relaciona con inmunodeficiencia severa. En estos pacientes causa lesiones neurológicas de alto grado e incluso la muerte. Suele aparecer como múltiples focos de lesión de predominio gangliobasal y con realce anular. Se presenta un caso clínico de neurotoxoplasmosis en paciente VIH con un patrón radiológico poco frecuente.


Cerebral toxoplasmosis or neurotoxoplasmosis is one of the most frequent infections by opportunistic agents in HIV-infected patients and is associated with severe immunodeficiency. In these patients, it causes high-grade neurological lesions and even death. It usually appears as multiple foci of lesions with gangliobasal predominance and annular enhancement. We present a clinical case of neurotoxoplasmosis in a HIV patient with an unusual radiological pattern.


Assuntos
Terapia de Imunossupressão , Diagnóstico por Imagem , Toxoplasmose Cerebral
13.
Animals (Basel) ; 11(12)2021 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-34944376

RESUMO

This pilot investigation aimed at studying the feasibility of using a low dose (0.2%) of dietary microalgae as a means of improving intestinal morphometry, body weight, and selected meat quality parameters in broilers. A total of 72 one-day-old ROSS 308 male chicks were randomly separated into four groups; three experimental pens in which the birds were fed with biomass from Tysochrysis lutea, Tetraselmis chuii, and Porphyridium cruentum over 30 days and a control group. T. chuii and P. cruentum had a positive effect with regard to body weight. In treated animals, duodenal and ileal sections showed characteristic tall and thin villi, with serrated surfaces and goblet cell differentiation. In both sections, values of the villus-height-to-crypt-depth ratio were increased by microalgae ingestion. The thawing weight loss of fillets was reduced in T. chuii-fed animals. The positive effects exerted by T. chuii and P. cruentum on intestinal architecture were associated with the improved body weight. Arguably, these outcomes exhibit the potential of using these species to enhance growth performance in broiler chickens by promoting gut homeostasis and thus nutrient absorption.

14.
Antibiotics (Basel) ; 10(11)2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34827328

RESUMO

Antimicrobial resistance genes are often associated with integrons, which promote their movement between and within DNA molecules. IntFinder 1.0 and I-VIP v1.2 were used for the detection of integrons and their associated resistance genes in assembled sequences and raw reads. A dataset comprising 1688 sequenced Salmonella enterica isolates from countries of the Andean Community was developed. A total of 749 and 680 integrons were identified by IntFinder 1.0 and I-VIP v1.2, respectively; class 2 integrons were the most abundant followed by class 1, whereas no class 3 integrons were detected. These elements were mainly associated with isolates from animal sources. S. Infantis ST32 contained the majority of integrons. Trimethoprim resistance genes (dfrA) were found in greater numbers than others, including aadA and bla genes. The presence of these resistance integrons may come as a response to antibiotic misuse, especially of co-trimoxazole. This represents a public health risk as novel resistant strains might appear due to gene dissemination. The information gathered from in silico studies not only contributes to our understanding of integron dynamics in pathogenic Salmonella, but also helps identify potential emergent patterns of resistance in the region, which is fundamental for developing pertinent antibiotic surveillance programs.

15.
Artigo em Inglês | MEDLINE | ID: mdl-34444455

RESUMO

Adherence to preventive measures is influenced by people's knowledge, attitudes and practices towards a disease; therefore, assessing knowledge of COVID-19 is critical in the overall effort to contain the outbreak. This cross-sectional study was conducted among undergraduates (n = 3621) of different programs and different levels of education associated with universities in north-central Ecuador. The form consisted of 32 questions covering demographics, symptoms, detection, treatment, transmission, prevention and knowledge of the virus. The rate of correct answers was 75.5% (21.1 ± 5 out of 28), with differences observed regarding program of study, educational level and location of institution (α = 0.05), although effect size analyses showed that these differences could not be considered large. Multiple linear regression analyses showed that lower scores were associated with initial stages of education, careers related to social sciences and location of institution. Participants possessed sufficient knowledge about detection, transmission and prevention, although they overestimated fatality rate and were less confident about the characteristics of the virus and the effectiveness of traditional medicine. Consequently, future educational programs must place emphasis on addressing deficient knowledge. Certainly, improving COVID-19 literacy will promote the appropriate application of protective measures aimed at preventing the virus' spread.


Assuntos
COVID-19 , Estudos Transversais , Equador/epidemiologia , Conhecimentos, Atitudes e Prática em Saúde , Humanos , SARS-CoV-2 , Estudantes , Inquéritos e Questionários
16.
Int J Mol Sci ; 22(16)2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34445505

RESUMO

Eukaryotic organisms such as plants are unable to utilise nitrogen gas (N2) directly as a source of this essential element and are dependent either on its biological conversion to ammonium by diazotrophic prokaryotes, or its supply as chemically synthesised nitrate fertiliser. The idea of genetically engineering crops with the capacity to fix N2 by introduction of the bacterial nitrogenase enzyme has long been discussed. However, the expression of an active nitrogenase must overcome several major challenges: the coordinated expression of multiple genes to assemble an enzyme complex containing several different metal cluster co-factors; the supply of sufficient ATP and reductant to the enzyme; the enzyme's sensitivity to oxygen; and the intracellular accumulation of ammonium. The chloroplast of plant cells represents an attractive location for nitrogenase expression, but engineering the organelle's genome is not yet feasible in most crop species. However, the unicellular green alga Chlamydomonas reinhardtii represents a simple model for photosynthetic eukaryotes with a genetically tractable chloroplast. In this review, we discuss the main advantages, and limitations, of this microalga as a testbed for producing such a complex multi-subunit enzyme. Furthermore, we suggest that a minimal set of six transgenes are necessary for chloroplast-localised synthesis of an 'Fe-only' nitrogenase, and from this set we demonstrate the stable expression and accumulation of the homocitrate synthase, NifV, under aerobic conditions. Arguably, further studies in C. reinhardtii aimed at testing expression and function of the full gene set would provide the groundwork for a concerted future effort to create nitrogen-fixing crops.


Assuntos
Chlamydomonas reinhardtii/crescimento & desenvolvimento , Cloroplastos/metabolismo , Engenharia Genética/métodos , Nitrogenase/genética , Chlamydomonas reinhardtii/genética , Cloroplastos/genética , Genoma de Cloroplastos , Fixação de Nitrogênio , Nitrogenase/metabolismo , Fotossíntese , Biologia Sintética
17.
Methods Mol Biol ; 2317: 293-304, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34028777

RESUMO

The availability of routine methods for the genetic engineering of the chloroplast genome of Chlamydomonas reinhardtii is allowing researchers to explore the use of this microalga as a phototrophic cell platform for synthesis of high value recombinant proteins and metabolites. However, the established method for delivering transforming DNA into the algal chloroplast involves microparticle bombardment using an expensive "gene gun". Furthermore, selection of transformant lines most commonly involves the use of a bacterial antibiotic resistance gene. In this chapter, we describe a simple and cheap delivery method in which cell-DNA suspensions are agitated with glass beads: a method that is more commonly used for nuclear transformation of Chlamydomonas. We also describe the use of plasmid expression vectors that target transgenes to a neutral site within the chloroplast genome between psbH and trnE2, and employ psbH as the selectable marker-thereby avoiding issues of unwanted antibiotic resistance genes in the resulting transgenic lines. Finally, we highlight a feature in our latest vectors in which the presence of a novel tRNA gene on the plasmid results in recognition within the chloroplast of UGA stop codons in transgenes as tryptophan codons. This feature simplifies the cloning of transgenes that are normally toxic to E. coli, serves as a biocontainment strategy restricting the functional escape of transgenes from the algal chloroplast to environmental microorganisms, and offers a simple system of temperature-regulated translation of transgenes.


Assuntos
Chlamydomonas reinhardtii/genética , Cloroplastos/genética , Engenharia Genética/métodos , Plantas Geneticamente Modificadas/genética , Transformação Genética , Chlamydomonas reinhardtii/crescimento & desenvolvimento , Vetores Genéticos , Genoma de Cloroplastos , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Transgenes
18.
Artigo em Inglês | MEDLINE | ID: mdl-33578745

RESUMO

Several public health measures have been implemented to contain the SARS-CoV-2 outbreak. The adherence to control measures is known to be influenced by people's knowledge, attitudes and practices with regard to the disease. This study aimed at assessing COVID-19 knowledge in individuals who were tested for the virus. An online cross-sectional survey of 32 items, adapted to the national context, was conducted among 1656 Ecuadorians. The mean knowledge score was 22.5 ± 3 out of 28, with significant differences being observed with regard to educational attainment. People with postgraduate training scored higher than those with college, secondary and elementary instruction. Indeed, multiple linear regression revealed that lower scores were associated significantly with the latter three levels of education. Interviewees were knowledgeable about the symptoms, detection, transmission and prevention of the disease. However, they were less assertive regarding the characteristics of the virus as well as the usefulness of traditional and unproven treatments. These outcomes indicated a lack of knowledge in fundamental aspects of virus biology, which may limit the effectiveness of further prevention campaigns. Conclusively, educational and communicational programs must place emphasis on explaining the basic molecular characteristics of SARS-CoV-2; such information will certainly contribute to improve the public's adherence to control measures.


Assuntos
COVID-19 , Conhecimentos, Atitudes e Prática em Saúde , Pandemias , Estudos Transversais , Equador/epidemiologia , Humanos , Inquéritos e Questionários
19.
Animals (Basel) ; 11(1)2021 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-33477806

RESUMO

This research was conducted to investigate if the administration of the probiotic Lactobacillus fermentum could influence body weight, intestinal morphometry and the cecal cytokine response in Campylobacter jejuni-infected chickens. Seventy-two 1-day old COBB 500 male chicks were allocated randomly into four experimental groups. (I) Control group (C), in which chicks were left untreated. (II) LB group, treated with L. fermentum. (III) Cj group, infected with C. jejuni and (IV) coexposure group in which both bacteria were administered. Body weight was registered and then all birds were slaughtered; samples from the small intestine and caecum were collected at 4- and 7-days post infection. The experiment lasted eleven days. Villi height and crypt depth ratios of the duodenum, jejunum and ileum were evaluated using appropriate software, while reverse transcription quantitative PCR (RT-qPCR) was utilized for assessing transcript levels of key cecal inflammatory cytokines (IL-1ß, IL-18, IL-17, IL-15, IL13 and IL-4). Campylobacter-infected birds showed lower body weight values than those supplemented with the probiotic; these birds, in turn, proved to be heavier than those reared under control conditions. L. fermentum administration improved morphometrical parameters of the duodenum, jejunum and ileum; in general, villi were larger and crypts deeper than those identified in control conditions. Moreover, the negative effects elicited by C. jejuni were not observed in chickens exposed to the probiotic. Significant differences were also determined with regards to transcript abundance of all evaluated cytokines in the caecum. C. jejuni induced a downregulation of the studied interleukins; however, such a response was heightened by administration of L. fermentum, with an increase rate of transcription that promoted a more effective response to a C. jejuni infection. The effects of experimental treatments proved to vary between sampling points. Conclusively, these results demonstrate that L. fermentum lessens the negative effects elicited by C. jejuni on body weight by alleviating the impact on intestinal morphometry and cecal cytokine response, which ultimately improve chicken growth performance.

20.
Ther Adv Respir Dis ; 14: 1753466620938553, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32643553

RESUMO

Precision oncology is the field that places emphasis on the diagnosis and treatment of tumors that harbor specific genomic alterations susceptible to inhibition or modulation. Although most alterations are only present in a minority of patients, a substantial effect on survival can be observed in this subgroup. Mass genome sequencing has led to the identification of a specific driver in the translocations of the tropomyosin receptor kinase family (NTRK) in a subset of rare tumors both in children and in adults, and to the development and investigation of Larotrectinib. This medication was granted approval by the US Food and Drug Administration for NTRK-positive tumors, regardless of histology or age group, as such, larotrectinib was the first in its kind to be approved under the premise that molecular pattern is more important than histology in terms of therapeutic approach. It yielded significant results in disease control with good tolerability across a wide range of diseases including rare pediatric tumors, salivary gland tumors, gliomas, soft-tissue sarcomas, and thyroid carcinomas. In addition, and by taking different approaches in clinical trial design and conducting allocation based on biomarkers, the effects of target therapies can be isolated and quantified. Moreover, and considering developing nations and resource-limited settings, precision oncology could offer a tool to reduce cancer-related disability and hospital costs. In addition, developing nations also present patients with rare tumors that lack a chance of treatment, outside of clinical trials. This, in turn, offers the possibility for international collaboration, and contributes to employment, education, and health service provisions. The reviews of this paper are available via the supplemental material section.


Assuntos
Biomarcadores Tumorais/genética , Países em Desenvolvimento , Fusão Gênica , Neoplasias Pulmonares/genética , Oncologia , Medicina de Precisão , Receptores Proteína Tirosina Quinases/genética , Receptores de Fator de Crescimento Neural/genética , Antineoplásicos/uso terapêutico , Países em Desenvolvimento/economia , Custos de Cuidados de Saúde , Acessibilidade aos Serviços de Saúde , Humanos , América Latina , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/economia , Neoplasias Pulmonares/mortalidade , Oncologia/economia , Técnicas de Diagnóstico Molecular , Terapia de Alvo Molecular , Medicina de Precisão/economia , Valor Preditivo dos Testes
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