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Pathogenic microorganisms play a crucial role in the global disease burden due to their ability to cause various diseases and spread through multiple transmission routes. Immunity tests identify antigens related to these pathogens, thereby confirming past infections and monitoring the host's immune response. Traditional pathogen detection methods, including enzyme-linked immunosorbent assays (ELISAs) and chemiluminescent immunoassays (CLIAs), are often labor-intensive, slow, and reliant on sophisticated equipment and skilled personnel, which can be limiting in resource-poor settings. In contrast, the development of microfluidic technologies presents a promising alternative, offering automation, miniaturization, and cost efficiency. These advanced methods are poised to replace traditional assays by streamlining processes and enabling rapid, high-throughput immunity testing for pathogens. This review highlights the latest advancements in microfluidic systems designed for rapid and high-throughput immunity testing, incorporating immunosensors, single molecule arrays (Simoas), a lateral flow assay (LFA), and smartphone integration. It focuses on key pathogenic microorganisms such as SARS-CoV-2, influenza, and the ZIKA virus (ZIKV). Additionally, the review discusses the challenges, commercialization prospects, and future directions to advance microfluidic systems for infectious disease detection.
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SARS-CoV-2 , Humanos , SARS-CoV-2/imunologia , SARS-CoV-2/isolamento & purificação , Microfluídica/métodos , Microfluídica/instrumentação , COVID-19/imunologia , COVID-19/diagnóstico , COVID-19/virologia , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos , Imunoensaio/métodos , Zika virus/imunologia , Dispositivos Lab-On-A-Chip , Técnicas Biossensoriais/métodos , Influenza Humana/diagnóstico , Influenza Humana/imunologia , Infecção por Zika virus/diagnóstico , Infecção por Zika virus/imunologiaRESUMO
During infection, the bacterial pathogen Legionella pneumophila manipulates a variety of host cell signaling pathways, including the Hippo pathway which controls cell proliferation and differentiation in eukaryotes. Our previous studies revealed that L. pneumophila encodes the effector kinase LegK7 which phosphorylates MOB1A, a highly conserved scaffold protein of the Hippo pathway. Here, we show that MOB1A, in addition to being a substrate of LegK7, also functions as an allosteric activator of its kinase activity. A crystallographic analysis of the LegK7-MOB1A complex revealed that the N-terminal half of LegK7 is structurally similar to eukaryotic protein kinases, and that MOB1A directly binds to the LegK7 kinase domain. Substitution of interface residues critical for complex formation abrogated allosteric activation of LegK7 both in vitro and within cells and diminished MOB1A phosphorylation. Importantly, the N-terminal extension (NTE) of MOB1A not only regulated complex formation with LegK7 but also served as a docking site for downstream substrates such as the transcriptional coregulator YAP1. Deletion of the NTE from MOB1A or addition of NTE peptides as binding competitors attenuated YAP1 recruitment to and phosphorylation by LegK7. By providing mechanistic insight into the formation and regulation of the LegK7-MOB1A complex, our study unravels a sophisticated molecular mimicry strategy that is used by L. pneumophila to take control of the host cell Hippo pathway.
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Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Bactérias/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Legionella pneumophila/metabolismo , Proteínas Quinases/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Regulação Alostérica , Animais , Proteínas de Bactérias/genética , Proteínas de Ciclo Celular/metabolismo , Células HEK293 , Interações Hospedeiro-Patógeno , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Legionella pneumophila/patogenicidade , Doença dos Legionários/microbiologia , Doença dos Legionários/patologia , Macrófagos Alveolares/microbiologia , Macrófagos Alveolares/patologia , Camundongos , Simulação de Dinâmica Molecular , Mimetismo Molecular , Fosforilação , Ligação Proteica , Proteínas Quinases/genética , Células RAW 264.7 , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transdução de Sinais , Fatores de Transcrição/metabolismo , Proteínas de Sinalização YAPRESUMO
PURPOSE: The purpose of this study is to compare the predisposing factors, clinical findings, treatment results, and prognosis for polymicrobial keratitis. METHODS: In this retrospective comparative case study, we identified the cases of polymicrobial keratitis from the microbiological records (n = 649) at Balcali Hospital, Çukurova University (Adana, Turkey; October 2010-2018). We included all the cases of infectious keratitis with two different types of microbial agents and grouped them as follows: group 1 (n = 25), bacterium-fungus coexistence; group 2 (n = 12), herpes simplex virus (HSV) or Acanthamoeba with bacterial infection; and group 3 (n = 7), HSV or Acanthamoeba with fungal infection. We compared the clinical and microbiological characteristics, and treatment outcomes among the groups. RESULTS: In our study, we found that 44 infectious keratitis cases (6.7%) were of polymicrobial nature. The mean follow-up period was 11.4 ± 17.8 months. In total, 17 different bacteria along with 3 different fungi, HSV, and Acanthamoeba were isolated. The most common bacterium was Staphylococcus epidermidis (25%). Most of the fungal pathogens were filamentous. Patients with initial treatment failure and requiring surgical intervention had larger infiltrates (p = 0.023, p = 0.003, respectively) than other patients. Older age was associated with delayed recovery and poor visual prognosis. CONCLUSIONS: Bacterial-fungus coexistence is the most common combination among patients, but other combinations should also be considered for suspected polymicrobial etiology. The corneal infiltrate size may be an important indicator of the course of disease and response to treatment. A closer and longer follow-up period should be planned for older patients.
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Ceratite por Acanthamoeba , Infecções Oculares Bacterianas , Ceratite , Idoso , Infecções Oculares Bacterianas/diagnóstico , Infecções Oculares Bacterianas/tratamento farmacológico , Fungos , Humanos , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Staphylococcus epidermidisRESUMO
This study aimed to assess the growth of Salmonella and Escherichia coli O157:H7 on lettuce exposed to isothermal and non-isothermal conditions. Pathogens were inoculated on lettuce separately and stored under isothermal condition at 5 °C, 10 °C, 25 °C, 37 °C for both bacteria, at 40 °C for Salmonella and 42 °C for E. coli O157:H7. Growth curves were built by fitting the data to the Baranyi's DMFit, generating R2 values greater than 0.92 for primary models. Secondary models were fitted with Ratkowsky equations, generating R2 values higher than 0.91 and RMSE lower than 0.1. Experimental data showed that both bacteria could grow at all temperatures. Also, the growth of both pathogens under non-isothermal conditions was studied simulating temperatures found from harvest to supermarkets in Brazil. Models were analysed by R2, RMSE, bias factor (Bf) and accuracy factor (Af). Salmonella and E. coli O157:H7 were able to grow in this temperature profile and the models could predict the behavior of these microorganisms on lettuce under isothermal and non-isothermal conditions. Based on the results, a negligible growth time (ς) was proposed to provide the time which lettuce could be exposed to a specific temperature and do not present an expressive growth of bacteria. The ς was developed based on Baranyi's primary model equation and on growth potential concept. ς is the value of lag phase added of the time necessary to population grow 0.5 log CFU/g. The ς of lettuce exposed to 37 °C was 1.3 h, while at 5 °C was 3.3 days.
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Escherichia coli O157/crescimento & desenvolvimento , Armazenamento de Alimentos/métodos , Lactuca/microbiologia , Salmonella/crescimento & desenvolvimento , Brasil , Contagem de Colônia Microbiana , TemperaturaRESUMO
Extranodal marginal zone lymphoma of mucosa associated lymphoid tissue (MALT) is an indolent B-cell non-Hodgkin lymphoma (NHL) arising in lymphoid populations that are induced by chronic inflammation in extra nodal sites. The stomach is the most commonly affected organ, and MALT lymphoma is clearly associated with a gastroduodenitis induced by a microbial pathogen, Helicobacter pylori, thus gastric MALT lymphoma represents a paradigm for evaluating inflammatory-associated lymphomagenesis. Variable levels of evidence have indicated a possible association between other microorganisms and non-gastric MALT lymphomas. In addition to infectious etiology, chronic inflammation arising as a result of autoimmune diseases such as Sjogren's syndrome or Hashimoto thyroiditis, poses a significant risk factor for developing NHL. Recently, genetic alterations affecting the NF-κB pathway, a major signaling pathway involved in many cancers, have been identified in MALT lymphoma. This review will present MALT lymphoma as an example of the close pathogenetic link between chronic microenvironmental inflammation and tumor development, showing how these observations can be integrated into daily clinical practice, also in terms of therapeutic implications, with particular focus on the NF-κB pathway.
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Infecções por Helicobacter/patologia , Inflamação/patologia , Linfoma de Zona Marginal Tipo Células B/patologia , Microambiente Tumoral/genética , Linfócitos B/patologia , Doença de Hashimoto/complicações , Doença de Hashimoto/microbiologia , Doença de Hashimoto/patologia , Infecções por Helicobacter/complicações , Infecções por Helicobacter/microbiologia , Helicobacter pylori/patogenicidade , Humanos , Inflamação/complicações , Inflamação/microbiologia , Linfoma de Zona Marginal Tipo Células B/complicações , Linfoma de Zona Marginal Tipo Células B/genética , Linfoma de Zona Marginal Tipo Células B/microbiologia , NF-kappa B/genética , Transdução de Sinais , Síndrome de Sjogren/complicações , Síndrome de Sjogren/microbiologia , Síndrome de Sjogren/patologiaRESUMO
Only a handful of microbial mosquito larval pathogens have been described to date. Sampling several natural enzootic infections of mosquito larvae in southwestern Florida indicated the presence of microbial pathogens capable of extensive larval mortality. A microscopic analysis of one sample site revealed extensive apparent growth of a Pythium-like microbe on mosquito larvae, with the highest degree of infection observed in the siphon and head regions. Structures consistent with sporangia were seen on infected insects after lactophenol blue staining, and higher-resolution scanning electron microscopy (SEM) micrographs showed sporangia and encysted zoospores targeting the head and siphon regions. The isolate was single-colony purified, and molecular identification targeting the ITS and COX1 loci coupled to phylogenetic reconstruction indicated that the isolate belonged to the Pythium genus but was distinct from its closest characterized species, P. inflatum. Morphological features were characterized, with the isolate showing rapid growth on all mycological media tested and relatively high thermotolerance, capable of robust growth at 37 °C; hence, it was designated P. thermoculicivorax. Sampling from a second series of natural infections of mosquito larvae resulted in the molecular identification of three Trichoderma isolates, one with high similarity to T. strigosum and the other two clustering closely with T. asperellum. These data highlight the occurrence of natural enzootic infections of mosquito larvae, potentially as a resource for the identification of new mosquito pathogens.
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Phenolic compounds are natural substances that are produced through the secondary metabolism of plants, fungi, and bacteria, in addition to being produced by chemical synthesis. These compounds have anti-inflammatory, antioxidant, and antimicrobial properties, among others. In this way, Brazil represents one of the most promising countries regarding phenolic compounds since it has a heterogeneous flora, with the presence of six distinct biomes (Cerrado, Amazon, Atlantic Forest, Caatinga, Pantanal, and Pampa). Recently, several studies have pointed to an era of antimicrobial resistance due to the unrestricted and large-scale use of antibiotics, which led to the emergence of some survival mechanisms of bacteria to these compounds. Therefore, the use of natural substances with antimicrobial action can help combat these resistant pathogens and represent a natural alternative that may be useful in animal nutrition for direct application in food and can be used in human nutrition to promote health. Therefore, this study aimed to (i) evaluate the phenolic compounds with antimicrobial properties isolated from plants present in Brazil, (ii) discuss the compounds across different classes (flavonoids, xanthones, coumarins, phenolic acids, and others), and (iii) address the structure-activity relationship of phenolic compounds that lead to antimicrobial action.
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Cell wall integrity is tightly regulated and maintained given that non-physiological modification of cell walls could render plants vulnerable to biotic and/or abiotic stresses. Expansins are plant cell wall-modifying proteins active during many developmental and physiological processes, but they can also be produced by bacteria and fungi during interaction with plant hosts. Cell wall alteration brought about by ectopic expression, overexpression, or exogenous addition of expansins from either eukaryote or prokaryote origin can in some instances provide resistance to pathogens, while in other cases plants become more susceptible to infection. In these circumstances altered cell wall mechanical properties might be directly responsible for pathogen resistance or susceptibility outcomes. Simultaneously, through membrane receptors for enzymatically released cell wall fragments or by sensing modified cell wall barrier properties, plants trigger intracellular signaling cascades inducing defense responses and reinforcement of the cell wall, contributing to various infection phenotypes, in which expansins might also be involved. Here, we review the plant immune response activated by cell wall surveillance mechanisms, cell wall fragments identified as responsible for immune responses, and expansin's roles in resistance and susceptibility of plants to pathogen attack.
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Among healthcare-associated infections, catheter-related bloodstream infection (CRBSI) shows a high case fatality rate and is serious threat. CRBSI are a problem to be eradicated. This study was conducted to reveal the growth characteristics of the causative microorganisms of CRBSI and investigate relevant control methods. The effects of biotin on growth of Candida albicans (C. albicans) in the nutrient solutions were investigated. Upon comparing general solutions and biotin-containing solutions, C. albicans showed auxotrophy against biotin, resulting in significant proliferative potential. CRBSI is caused by biofilm formation in the catheter lumen and subsequent proliferation. The effect of biotin on the colonization of C. albicans in the catheter lumen was evaluated. Candida albicans colonization in the catheter lumen and subsequent proliferation were significantly higher than those in control solutions. To investigate methods for CRBSI control, effects on pathogenic microorganisms were examined by screening for nutrient solutions with antimicrobial activity, using a catheter-lumen contamination model. A commercially available solution (PLAS-AMINO® injection; PA) containing the highest amount of sodium bisulfite was selected. Gram-positive or negative bacteria and C. albicans were used as the causative microorganisms of CRBSI in the study. Dripping PA into each catheter-lumen contamination model demonstrated bactericidal effects against all bacteria tested and strong growth-inhibitory effects on C. albicans. By using PA for contamination inside the catheter, sterilization and suppression of bacterial growth can be expected without having to remove central venous catheters and/or central venous access devices. This review provides valuable findings for the development of novel control methods for CRBSI.
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Cateterismo Venoso Central , Sepse , Bactérias , Catéteres , Humanos , NutrientesRESUMO
Achromobacter denitrificans is an environmental opportunistic pathogen that is infecting a large number of immunocompromised patients. A more recently identified strain from the historical collection of strains of Achromobacter denitrificans is Achromobacter mucicolens. In hosts with a variety of underlying diseases, Achromobacter spp. can induce a wide spectrum of disorders. Because of the bacterium's intrinsic genetic constitution and resistance gained over time, antibiotics are challenged to handle A. mucicolens. Due to the fact that A. mucicolens is rare and its taxonomy is not completely understood, it is difficult to define clinical symptoms, acquisition risk factors, and thus the best therapeutic course of action. To help comprehend this intrinsic and acquired resistance, we analyzed the entire genome of the A. mucicolens IA strain and utilized bioinformatics methods to estimate the strain's probable drug resistance profile. In our study, we have isolated and cultured a clinically important A. mucicolens strain and subjected it to antimicrobial susceptibility tests against antibiotics in the Vitek 2 testing system. The strain's genome sequence as well as an investigation of 27 of its phenotypic traits provides important information regarding this pathogen. The genome of this A. mucicolens IA strain possesses a number of antibiotic resistance genes that code for efflux pump systems and other antibiotic-regulating as well as -modifying enzymes. Our research analysis predicted genes involved in drug resistance, including genes for efflux pump systems, antibiotic efflux, antibiotic inactivation, and antibiotic target alteration. In vitro studies validated the genomic evidence for its ability to exhibit resistance against a wide range of antibiotics. Our investigation paves the way for more research on understanding the functioning of the key discovered genes that contribute toward the pathogenicity of A. mucicolens and hence gives new information and treatment options for this emerging pathogen. IMPORTANCEAchromobacter species are well-known opportunistic human pathogens that can be found in water and soil and most commonly in hospital settings. They thrive in immunocompromised individuals, producing sporadic cases of pneumonia, septicemia, peritonitis, urinary tract infections, and other illnesses. Achromobacter strains are inherently resistant to a wide spectrum of antibiotics, making them difficult to treat promptly. The strain under study, A. mucicolens, was notably resistant to various antibiotics, and the infection could be controlled only after several rounds of prescription medications at different doses. This consumed a lot of time and put the already immunosuppressed leukemic patient through a great ordeal. The study aimed to raise awareness about the importance of the Achromobacter bacterium's lethality, and doctors should evaluate the bacterium's potential for resistance before prescribing antibiotics. Sanitation and other precautions should also be implemented in hospitals and other public places.
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Achromobacter denitrificans , Achromobacter , Achromobacter/genética , Achromobacter denitrificans/genética , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos , Genômica , Humanos , Testes de Sensibilidade MicrobianaRESUMO
Plants and animals utilize various regulatory mechanisms for control of gene expression during development in different tissues and cell types. About 30 years ago, a new mechanism of gene regulation, termed RNA interference (RNAi), was discovered and proved revolutionary for the mechanistic understanding of gene regulation. Noncoding RNAs, including short, 21-24 nucleotide (nt) long microRNAs (miRNAs), endogenously-generated from MIR genes, are key components of RNAi processes, by post-transcriptionally controlling transcripts with antisense complementarity through either translational repression or mRNA degradation. Since their discovery, important roles in regulation of ontogenetic development, cell differentiation, proliferation, and apoptosis in eukaryotes have been elucidated. In plants, miRNAs are known regulatory elements of basic endogenous functions and responses to the environmental stimuli. While the role of miRNAs in regulation of nutrient uptake, circadian clock and general response to abiotic stress is already well understood, a comprehensive understanding of their immune-regulatory roles in response to various biotic stress factors has not yet been achieved. This review summarizes the current understanding of the function of miRNAs and their targets in plants during interaction with microbial pathogens and symbionts. Additionally, we provide a consensus conclusion regarding the typical induction or repression response of conserved miRNA families to pathogenic and beneficial fungi, bacteria, and oomycetes, as well as an outlook of agronomic application of miRNAs in plants. Further investigation of plant miRNAs responsive to microbes, aided with novel sequencing and bioinformatics approaches for discovery and prediction in non-model organisms holds great potential for development of new forms of plant protection.
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Regulação da Expressão Gênica de Plantas , MicroRNAs/genética , Desenvolvimento Vegetal/genética , Reguladores de Crescimento de Plantas/genética , RNA de Plantas , Estresse Fisiológico/genética , Estresse Fisiológico/fisiologiaRESUMO
Foodborne diseases (FBDs) remain a global public health concern. Climatic factors such as wind-chill temperature, rainfall, and relative humidity affect the incidence of several FBDs. This study was performed to analyze how the various factors of the climate influence the incidence and severity of FBDs. This study retrospectively analyzed the results of multiplex polymerase chain reaction (mPCR) tests for diarrhea-causing bacteria performed on 2300 fecal samples obtained from patients at Dankook University Hospital, Cheonan, from June 2010 to December 2019. The Clostridioides difficile toxin B infection rate positively correlated with the intensity of sunshine, and the content of particulate matter. The Campylobacter spp. infection rate positively correlated with wind-chill temperature and the content of particulate matter. The Escherichia coli O157:H7 infection rate positively correlated with relative humidity. These findings may explain the dynamics and risks of Clostridioides difficile toxin B, Clostridium perfringens, Campylobacter spp., and Escherichia coli O157:H7 infection. They may help predict interrelationships among climatic factors and standardize national environmental health policies. However, in-depth research with large-scale data, molecular biology, and epidemiology would be required going forward. Future research would also require objective indicators of the changes in the prevalence of FBD-causing microbial pathogens for the effective prevention and management of these bacterial infections.
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Campylobacter , Escherichia coli O157 , Clostridioides , Clostridium perfringens , Humanos , Incidência , Estudos RetrospectivosRESUMO
BACKGROUND: Planning for control of tuberculosis would need to screen and identify individuals susceptible to TB. Due to the weakness of immune system in diabetic patients, it is more likely for them to reactivate latent TB infection. Regarding the increasing number of diabetics in the community, in this study efforts have been made to estimate the frequency of individuals who have tuberculosis and diabetes mellitus (TB-DM) simultaneously, as it could help making preventive decisions to reduce TB in this part of Iran. MATERIALS AND METHODS: In this study, 329 cases of confirmed TB patients were divided into two groups of diabetic and non-diabetic, then demographic information and clinical variables have been compared between the two groups. RESULTS: Among the examined subjects, 47 patients (14.29 %) had suffered from diabetes mellitus and tuberculosis. All of the DM patients had pulmonary tuberculosis and 87.23% of them were over the age of 50. CONCLUSION: Majority of DM-TB patients were over 50 years of age and also more than half of them were women. So it seems that for DM women over the age of 50, to detect tuberculosis, screening tests such as PPD may be necessary.
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Diabetes Mellitus/epidemiologia , Tuberculose/epidemiologia , Adolescente , Adulto , Fatores Etários , Idoso , Comorbidade , Feminino , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Caracteres Sexuais , Adulto JovemRESUMO
The holistic approach of One Health, which sees human, animal, plant, and environmental health as a unit, rather than discrete parts, requires not only interdisciplinary cooperation, but standardized methods for communicating and archiving data, enabling participants to easily share what they have learned and allow others to build upon their findings. Ongoing work by NCBI and the GenomeTrakr project illustrates how open data platforms can help meet the needs of federal and state regulators, public health laboratories, departments of agriculture, and universities. Here we describe how microbial pathogen surveillance can be transformed by having an open access database along with Best Practices for contributors to follow. First, we describe the open pathogen surveillance framework, hosted on the NCBI platform. We cover the current community standards for WGS quality, provide an SOP for assessing your own sequence quality and recommend QC thresholds for all submitters to follow. We then provide an overview of NCBI data submission along with step by step details. And finally, we provide curation guidance and an SOP for keeping your public data current within the database. These Best Practices can be models for other open data projects, thereby advancing the One Health goals of Findable, Accessible, Interoperable and Re-usable (FAIR) data.
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Nanotechnology is a rapidly growing scientific field and has attracted a great interest over the last few years because of its abundant applications. Green nanotechnology is a multidisciplinary field that has emerged as a rapidly developing research area, serving as an important technique that emphasize on making the procedure which are clean, non-hazardous, and especially environmentally friendly, in contrast with chemical and physical methods currently employed for nanosynthesis. The biogenic routes could be termed green as these do not involve the use of highly toxic chemicals or elevated energy inputs during the synthesis. Differences in the bio-reducing agents employed for nanosynthesis can lead to the production of nanoparticles (NPs) having distinct shapes, sizes, and bioactivity. The exquitiveness of the green fabricated NPs have capacitated their potential applications in various sectors such as biomedicine, pharmacology, food science, agriculture, and environmental engineering. The present review summarizes current knowledge on various biogenic synthesis methods, relying on plants, waste biomass, and biopolymers and their reducing and stabilizing agents to fabricate nanomaterials. The main emphasis has been given on the current status and future challenges related to the wide-scale fabrication of nanoparticles for environmental remediation, pathogenicity, and agricultural applications.
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Materiais Biocompatíveis/síntese química , Nanopartículas Metálicas/química , Nanotecnologia/métodos , Materiais Biocompatíveis/química , Química Verde , PlantasRESUMO
DNA-based molecular detection of microbial pathogens in complex environments is still plagued by sensitivity, specificity and robustness issues. We propose to address these issues by viewing them as inadvertent consequences of requiring specific and adequate amplification (SAA) of target DNA molecules by current PCR methods. Using the invA gene of Salmonella as the model system, we investigated if next generation sequencing (NGS) can be used to directly detect target sequences in false-negative PCR reaction (PCR-NGS) in order to remove the SAA requirement from PCR. False-negative PCR and qPCR reactions were first created using serial dilutions of laboratory-prepared Salmonella genomic DNA and then analyzed directly by NGS. Target invA sequences were detected in all false-negative PCR and qPCR reactions, which lowered the method detection limits near the theoretical minimum of single gene copy detection. The capability of the PCR-NGS approach in correcting false negativity was further tested and confirmed under more environmentally relevant conditions using Salmonella-spiked stream water and sediment samples. Finally, the PCR-NGS approach was applied to ten urban stream water samples and detected invA sequences in eight samples that would be otherwise deemed Salmonella negative. Analysis of the non-target sequences in the false-negative reactions helped to identify primer dime-like short sequences as the main cause of the false negativity. Together, the results demonstrated that the PCR-NGS approach can significantly improve method sensitivity, correct false-negative detections, and enable sequence-based analysis for failure diagnostics in complex environmental samples.
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Bactérias/genética , Bactérias/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Proteínas de Bactérias/genética , Sequência de Bases , DNA Bacteriano/análise , Microbiologia Ambiental , Sedimentos Geológicos , Havaí , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Salmonella/genética , Salmonella/isolamento & purificação , Sensibilidade e Especificidade , Microbiologia da ÁguaRESUMO
Presently, the discovery of effective drugs and pesticides from eco-friendly biological sources is an important challenge in the field of life sciences. The present research was aimed for standardizing an innovative approach in the evaluation of the biological potentiality of the metabolites of fish-associated bacteria. We have identified 17 skin-associated bacteria from the freshwater fish, giant danio, Devario aquipinnatus. They were screened through biofilm forming and extracellular enzyme producing ability. The results of preliminary antibacterial evaluation of the bacterial supernatants underlined the importance of three potential strains (BH8, BH10 and BH11) for further applied research. Hence, such strains were subsequently subjected to a novel extraction procedure to overcome the difficulties found in polar solvents mixed with the supernatant. The lyophilized cell-free supernatant (LCFS) of 3 isolates were individually extracted by using methanol. During the testing of LCFS's methanolic extract (LCFS-ME) of 3 isolates, only the extract of BH11-strain exhibited potent inhibitory activity against the pathogenic bacteria and fungi. Furthermore, the larvicidal and mosquitocidal assays on the filariasis vector, Culex quinquefasciatus also showed its potent toxicity on both the adults and developmental instars of mosquito. Through molecular and phylogenetic analyses, the BH11 strain was identified as Salmonella bongori (KR350635). The present finding emphasized that the S. bongori could be an important novel source of effective antimicrobials and mosquitocidal agents.
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Anti-Infecciosos/farmacologia , Cyprinidae/microbiologia , Inseticidas/farmacologia , Mosquitos Vetores/efeitos dos fármacos , Salmonella/química , Aedes/efeitos dos fármacos , Animais , Anopheles/efeitos dos fármacos , Culex/efeitos dos fármacos , Meios de Cultura/química , Meios de Cultura/metabolismo , Avaliação Pré-Clínica de Medicamentos/métodos , Liofilização , Água Doce , Larva/efeitos dos fármacos , Filogenia , Salmonella/citologia , Salmonella/genéticaRESUMO
We review the sexual processes common in pathogenic microorganisms and assess the primary adaptive benefit of such processes. The pathogenic microorganisms considered include bacteria, microbial eukaryotes, and viruses. The sexual processes include bacterial transformation, eukaryotic meiotic sex and virus multiplicity reactivation. Recent evidence shows that sexual processes are common in microbial pathogens. A major general challenge to pathogen survival and infectivity is the need to overcome the hostile defenses of their target host. These defenses characteristically involve production of stresses, including oxidative stress, that can damage the pathogen's genome. Pathogens appear generally to possess enzyme systems that are central to sex and are also associated with a particular type of genomic repair process, recombinational repair. For some pathogens, it has been directly demonstrated that infectivity and virulence depend on sex. The evidence reviewed here supports the conclusion that the primary benefit of sex in pathogens is the repair of genomic damages that would otherwise be deleterious or lethal. This conclusion is in agreement with similar conclusions derived from non-pathogenic model species of bacteria, microbial eukaryotes and viruses. In several pathogenic species it has been shown that the two partner genomes that engage in sex are most often clonally related or closely related genetically. Thus, in pathogenic species, sexual interactions likely generate little or no genetic variation among progeny. However, infrequent outcrossing can occur in these sexual species and this may have important long term consequences.
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Suscetibilidade a Doenças , Interações Hospedeiro-Patógeno , Interações Microbianas , Microbiologia , Fenômenos Fisiológicos Bacterianos , Reparo do DNA , Fungos/fisiologia , Recombinação Genética , Transformação Genética , Fenômenos Fisiológicos ViraisRESUMO
Over the last few years, nanotechnology is increasingly developing in scientific sector, which has attracted a great deal of interest because of its abundant applications in almost all the areas. In recent times, green nanotechnology is a relative and multidisciplinary field that has emerged as a rapidly developing research area. This is serving as an important technique that spotlight on making the procedure which is clean, safe and in particular environtmentally friendly, in a gap with the currently employed methods such as chemical and physical methods for nanosynthesis. The present review recaps the existing knowledge on various biogenic synthesis methods relying on bacteria, fungi, yeast, algae, viruses and on using biomolecules. The green nanosynthesis refers to the employment of reducing and stabilizing agents from plants and other natural resources, to fabricate nanomaterials. The green synthesis method does not engage the use of exceedingly venomous chemicals or elevated energy inputs during the synthesis. Nanoparticles (NPs) with distinct shapes, sizes and bioactivity can be produced from the variations in the bio-reducing agents employed for nanosynthesis. Hence, this review article summarizes the present information regarding the biological methods which are employed to fabricate greener, safer, and environmentally sustainable nanosynthesis routes. This review mainly highlights the wide-scale fabrication of NPs via green synthesis for biomedical and agricultural applications.