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1.
Sci China Life Sci ; 67(6): 1292-1301, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38489008

RESUMO

Antimicrobial resistance (AMR) poses a critical threat to global health and development, with environmental factors-particularly in urban areas-contributing significantly to the spread of antibiotic resistance genes (ARGs). However, most research to date has been conducted at a local level, leaving significant gaps in our understanding of the global status of antibiotic resistance in urban environments. To address this issue, we thoroughly analyzed a total of 86,213 ARGs detected within 4,728 metagenome samples, which were collected by the MetaSUB International Consortium involving diverse urban environments in 60 cities of 27 countries, utilizing a deep-learning based methodology. Our findings demonstrated the strong geographical specificity of urban environmental resistome, and their correlation with various local socioeconomic and medical conditions. We also identified distinctive evolutionary patterns of ARG-related biosynthetic gene clusters (BGCs) across different countries, and discovered that the urban environment represents a rich source of novel antibiotics. Our study provides a comprehensive overview of the global urban environmental resistome, and fills a significant gap in our knowledge of large-scale urban antibiotic resistome analysis.


Assuntos
Antibacterianos , Cidades , Humanos , Antibacterianos/farmacologia , Fatores Socioeconômicos , Metagenoma/genética , Farmacorresistência Bacteriana/genética , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Bactérias/genética , Bactérias/efeitos dos fármacos , Bactérias/classificação , Família Multigênica , Saúde Global
2.
PNAS Nexus ; 2(2): pgac301, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36743472

RESUMO

An accepted murine analogue for the environmental behavior of human SARS coronaviruses was aerosolized in microdroplets of its culture media and saliva to observe the decay of its airborne infectious potential under relative humidity (RH) conditions relevant to conditioned indoor air. Contained in a dark, 10 m3 chamber maintained at 22°C, murine hepatitis virus (MHV) was entrained in artificial saliva particles that were aerosolized in size distributions that mimic SARS-CoV-2 virus expelled from infected humans' respiration. As judged by quantitative PCR, more than 95% of the airborne MHV aerosolized was recovered from microdroplets with mean aerodynamic diameters between 0.56 and 5.6 µm. As judged by its half-life, calculated from the median tissue culture infectious dose (TCID50), saliva was protective of airborne murine coronavirus through a RH range recommended for conditioned indoor air (60% < RH < 40%; average half-life = 60 minutes). However, its average half-life doubled to 120 minutes when RH was maintained at 25%. Saliva microaerosol was dominated by carbohydrates, which presented hallmarks of vitrification without efflorescence at low RH. These results suggest that dehydrating carbohydrates can affect the infectious potential coronaviruses exhibit while airborne, significantly extending their persistence under the drier humidity conditions encountered indoors.

3.
Artigo em Inglês | MEDLINE | ID: mdl-35329300

RESUMO

Home healthcare workers (HHCWs) are subjected to variable working environments which increase their risk of being exposed to numerous occupational hazards. One of the potential occupational hazards within the industry includes exposure to bioaerosols. This study aimed to characterize concentrations of three types of bioaerosols utilizing a novel fluorescence-based direct-reading instrument during seven activities that HHCWs typically encounter in patients' homes. Bioaerosols were measured in an indoor residence throughout all seasons in Cincinnati, OH, USA. A fluorescence-based direct-reading instrument (InstaScope, DetectionTek, Boulder, CO, USA) was utilized for all data collection. Total particle counts and concentrations for each particle type, including fluorescent and non-fluorescent particles, were utilized to form the response variable, a normalized concentration calculated as a ratio of concentration during activity to the background concentration. Walking experiments produced a median concentration ratio of 52.45 and 2.77 for pollen and fungi, respectively. Fungi and bacteria produced the highest and lowest median concentration ratios of 17.81 and 1.90 for showering, respectively. Lastly, our current study showed that sleeping activity did not increase bioaerosol concentrations. We further conclude that utilizing direct-reading methods may save time and effort in bioaerosol-exposure assessment.


Assuntos
Poluição do Ar em Ambientes Fechados , Exposição Ocupacional , Aerossóis/análise , Microbiologia do Ar , Poluição do Ar em Ambientes Fechados/análise , Atenção à Saúde , Monitoramento Ambiental/métodos , Fluorescência , Fungos , Humanos , Exposição Ocupacional/análise
4.
Eur J Pediatr ; 181(3): 1037-1045, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34694507

RESUMO

Children with acute leukaemia (AL) are a high-risk population for infections and life-threatening conditions requiring paediatric intensive care unit (PICU) admission, presenting an increased mortality rate. A few literature exists about PICU outcomes in this kind of patients, especially with haematopoietic stem cell transplant (HSCT) background. We investigated the clinical and epidemiological characteristics of these patients as well as their outcomes. A retrospective, single-centre analytical/observational study was conducted from January 2011 to December 2018 in the PICU of a tertiary care hospital. AL patients from 28 days to 18 years old admitted to the PICU were included, excluding those with histories of HSCT or CAR T-cell therapy. We collected epidemiological and clinical characteristics, laboratory and microbiology results and outcomes. Forty-three patients with AL required urgent admission (35 lymphoblastic and 8 myeloblastic) for 63 different episodes. The main reasons were sepsis (21, 33.3%), hyperleukocytosis (12, 19%), respiratory failure (11, 17.5%) and seizures (8, 12.7%). Nineteen (30.2%) required inotropic support, and fifteen (23.8%) required mechanical ventilation. Three patients died at the hospital (3/43, 6.9%). Sixty-day mortality was 9.3%, and 1-year mortality was 13.9%. There was no differences regarding the type of AL and 60-day mortality (log-rank 2.652, p = 0.103).Conclusion: In our study, the main cause of admission for AL patients was infection, which was associated to more severity and longer hospital admission. What is Known: • Acute leukaemia is the most common childhood cancer. Admission to a paediatric intensive care unit is required in 30% of children with acute leukaemia. • Regarding the outcomes of children with acute leukaemia that require admission to the intensive care unit data are scarce. What is New: • Mortality in acute leukaemia patients admitted to the paediatric intensive care unit is lower than that of patients with a history of stem cell therapy but higher than that of patients with solid tumours. • The main reason for admission was sepsis, which is related in literature to more severity and long length of stay.


Assuntos
Unidades de Terapia Intensiva Pediátrica , Leucemia Mieloide Aguda , Criança , Hospitalização , Humanos , Lactente , Leucemia Mieloide Aguda/terapia , Estudos Retrospectivos , Fatores de Risco
5.
Eur J Pediatr ; 181(2): 671-677, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34519852

RESUMO

One previous study recommended oral and outpatient management for those infants aged 60-90 days with urinary tract infection (UTI) meeting the low-risk criteria identified: to be well-appearing and to have a procalcitonin value of < 0.7 ng/mL. A retrospective study was conducted, including infants aged 29 to 90 days with UTI from 2014 to 2019, to validate these low-risk criteria identified and determine the adherence to the new algorithm for managing these patients at the Emergency Department. Two hundred one patients were included; 105 (52.2%) were aged 60 to 90 days. Twelve (6%, 95% CI 3.4-10.1%) had bacteremia. One hundred thirty-six (67.7%) infants met low-risk criteria; none had a positive blood culture (0%, 95% CI 0-2.7%). Overall protocol adherence was 90.6%. One hundred and forty-four (71.6%) infants were admitted to the hospital; all patients meeting high-risk criteria were hospitalized. Among the 57 (28.4%) infants initially sent home, 4 (7.0%) required later hospital admission.Conclusions: A prediction rule including general appearance and procalcitonin is highly accurate in identifying young infants with UTI at low risk for bacteremia. Outpatient management with appropriate follow-up is safe for these infants. What is Known: • Patients under 2-3 months of age with a presumptive urinary tract infection (UTI) are commonly hospitalized because of concerns regarding concomitant bacteremia. What is New: • A prediction rule including general appearance and procalcitonin is highly accurate in identifying young infants with UTI at low risk for bacteremia. Outpatient management with appropriate follow-up is safe for these infants.


Assuntos
Bacteriemia , Infecções Urinárias , Adulto , Idoso , Idoso de 80 Anos ou mais , Bacteriemia/diagnóstico , Febre , Humanos , Lactente , Pessoa de Meia-Idade , Pacientes Ambulatoriais , Estudos Retrospectivos , Infecções Urinárias/diagnóstico
6.
Environ Res ; 207: 112183, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-34637759

RESUMO

In urban ecosystems, microbes play a key role in maintaining major ecological functions that directly support human health and city life. However, the knowledge about the species composition and functions involved in urban environments is still limited, which is largely due to the lack of reference genomes in metagenomic studies comprises more than half of unclassified reads. Here we uncovered 732 novel bacterial species from 4728 samples collected from various common surface with the matching materials in the mass transit system across 60 cities by the MetaSUB Consortium. The number of novel species is significantly and positively correlated with the city population, and more novel species can be identified in the skin-associated samples. The in-depth analysis of the new gene catalog showed that the functional terms have a significant geographical distinguishability. Moreover, we revealed that more biosynthetic gene clusters (BGCs) can be found in novel species. The co-occurrence relationship between BGCs and genera and the geographical specificity of BGCs can also provide us more information for the synthesis pathways of natural products. Expanded the known urban microbiome diversity and suggested additional mechanisms for taxonomic and functional characterization of the urban microbiome. Considering the great impact of urban microbiomes on human life, our study can also facilitate the microbial interaction analysis between human and urban environment.


Assuntos
Metagenoma , Microbiota , Bactérias/genética , Humanos , Metagenômica , Interações Microbianas , Microbiota/genética
7.
Indoor Air ; 32(1): e12975, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34897813

RESUMO

Fluorescent aerosol cytometry (FAC) was compared to concurrent recovery of airborne ß-N-acetylhexosaminidase (NAHA) and quantitative polymerase chain reaction (qPCR) for the respective ability of these methods to detect significant changes in airborne fungal loads in response to building renovations. Composite, site-randomized indoor aerosol samples for airborne fungi measurements were acquired from more than 70 occupied classrooms in 26 different public schools in the Colorado Rocky Mountain Front Range region of the United States. As judged by ANOVA and Pearson's correlation test, statistically significant associations were observed between real-time FAC and airborne NAHA levels, which detected significant reductions in airborne fungal loads immediately following building rehabilitations. With lower confidence, a statistically significant association was also resolved between fluorescing aerosols, NAHA levels, and the recovery of fungal 18S rRNA gene copies by qPCR from simultaneous, collocated aerosol samples. Quantitative differences encountered between the recovery of common genomic markers for airborne fungi and that of optical and biochemical methods are attributed to the variance in 18S rRNA target gene copies that different fungal species can host.


Assuntos
Microbiologia do Ar , Poluição do Ar em Ambientes Fechados , Aerossóis , Poluição do Ar em Ambientes Fechados/análise , Fluorescência , Fungos/genética , Genômica , Hexosaminidases , Instituições Acadêmicas , beta-N-Acetil-Hexosaminidases
8.
Am J Infect Control ; 49(4): 464-468, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33347935

RESUMO

BACKGROUND: Schools represent high occupancy environments and well-documented high-risk locations for the transmission of respiratory viruses. The goal of this study was to report on the area density, occurrence, and type of respiratory viruses on desks in primary school classrooms. METHODS: Quantitative reverse transcription polymerase chain reaction (qPCR) techniques were employed to measure nucleic acid area densities from a broad range of human adenoviruses and rhinoviruses, as well as coronavirus OC43, influenza A, and norovirus GI. Every two weeks, virus monitoring was conducted on the desks of four primary school classrooms in Colorado, USA, during the 2019 respiratory virus season. RESULTS: DNA and RNA from respiratory viruses and norovirus were recovered from more than 20% of the desks sampled; occurrence patterns that indicate a greater than 60% probability of encountering any virus, if more than five desks were occupied in a day. Rhinoviruses and adenoviruses were the most commonly detected viruses as judged by the composite of occurrence and number of gene copies recovered. Desktop adenosine triphosphate monitoring did not predict the recovery of viral genomic materials on desks. School desks can be commonly contaminated with respiratory viruses. CONCLUSIONS: Genomic surveys of the identity, distribution and abundance of human viruses on "high-touch" surfaces, can help inform risk assessments, design cleaning interventions, and may be useful for infection surveillance.


Assuntos
Decoração de Interiores e Mobiliário , Vírus de RNA/isolamento & purificação , Infecções Respiratórias/virologia , Instituições Acadêmicas , Colorado/epidemiologia , DNA Viral/isolamento & purificação , Humanos , Vigilância da População , Vírus de RNA/genética , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real , Infecções Respiratórias/epidemiologia , Medição de Risco
9.
J Microbiol Methods ; 157: 1-3, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30557586

RESUMO

A condensation growth tube was adapted to capture bacterial bioaerosols directly into genomic preservatives. As judged by quantitative PCR and direct microscopy, bioaerosol condensation capture conserves airborne microbes' genomes as they exist in the atmospheric environment. This method circumvents the collection stresses bioaerosols experience on air filters, impactors and impingers.


Assuntos
Aerossóis , Microbiologia do Ar , Bacillus subtilis/crescimento & desenvolvimento , Bacillus subtilis/genética , Monitoramento Ambiental , Filtração/instrumentação , Filtração/métodos
10.
Genome Announc ; 6(19)2018 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-29748412

RESUMO

Mesorhizobium helmanticense is a novel species that was isolated from root nodules of Lotus corniculatus grown in an alfisol soil from Carbajosa de la Sagrada, a Mediterranean region in the province of Salamanca in northwest Spain. The whole-genome sequence of the type strain M. helmanticense CSLC115N is reported in this study.

11.
Biochim Biophys Acta ; 1864(4): 400-8, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26825284

RESUMO

Protein palmitoylation has been shown to be an important post-translational modification in eukaryotic cells. This modification alters the localization and/or the function of the targeted protein. In recent years, protein palmitoylation has risen in importance in apicomplexan parasites as well. In Toxoplasma gondii, some proteins have been reported to be modified by palmitate. With the development of new techniques that allow the isolation of palmitoylated proteins, this significant post-translational modification has begun to be studied in more detail in T. gondii. Here we describe the palmitoylome of the tachyzoite stage of T. gondii using a combination of the acyl-biotin exchange chemistry method and mass spectrometry analysis. We identified 401 proteins found in multiple cellular compartments, with a wide range of functions that vary from metabolic processes, gliding and host-cell invasion to even regulation of transcription and translation. Besides, we found that more rhoptry proteins than the ones already described for Toxoplasma are palmitoylated, suggesting an important role for this modification in the invasion mechanism of the host-cell. This study documents that protein palmitoylation is a common modification in T. gondii that could have an impact on different cellular processes.


Assuntos
Processamento de Proteína Pós-Traducional , Proteínas de Protozoários/análise , Toxoplasma/química , Lipoilação , Proteínas de Protozoários/química
12.
J Biomed Biotechnol ; 2012: 483969, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23093847

RESUMO

Apicomplexan parasites comprise a broad variety of protozoan parasites, including Toxoplasma gondii, Plasmodium, Eimeria, and Cryptosporidium species. Being intracellular parasites, the success in establishing pathogenesis relies in their ability to infect a host-cell and replicate within it. Protein palmitoylation is known to affect many aspects of cell biology. Furthermore, palmitoylation has recently been shown to affect important processes in T. gondii such as replication, invasion, and gliding. Thus, this paper focuses on the importance of protein palmitoylation in the pathogenesis of apicomplexan parasites.


Assuntos
Apicomplexa/fisiologia , Apicomplexa/parasitologia , Lipoilação/fisiologia , Proteínas de Protozoários/metabolismo
13.
Mol Biochem Parasitol ; 181(2): 125-33, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22057350

RESUMO

The apicoplast is a highly specialized organelle that mediates required functions in the growth and replication of apicomplexan parasites. Despite structural conservation of the apicoplast among different parasite genera and species, there are also critical differences in the metabolic requirements of different parasites and at different stages of the life cycle. To specifically compare apicoplast pathways between parasites that have both common and unique stages, we characterized the apicoplast in Babesia bovis, which has only intraerythrocytic asexual stages in the mammalian host, and compared it to that of Plasmodium falciparum, which has both asexual intraerythrocytic and hepatic stages. Specifically focusing on the type II fatty acid (FASII) and isoprenoid (MEP) biosynthesis pathways, we searched for pathway components and retention of active sites within the genome, localized key components [acyl carrier protein (ACP) and 4-hydroxy-3-methylbut-2-enyl diphosphate reductase (LytB)] to the apicoplast, and demonstrated that the N-terminal bipartite signals of both proteins are required and sufficient for trafficking to the apicoplast lumen. Using specific pharmacologic inhibition, we demonstrated that MEP biosynthesis may be disrupted and its presence is required for intraerythrocytic growth of B. bovis asexual stages, consistent with the genomic pathway analysis and with its requirement in the asexual erythrocytic stages of P. falciparum. In contrast, FASII biosynthesis may or may not be present and specific drug targets did not have any inhibitory effect to B. bovis intraerythrocytic growth, which is consistent with the lack of requirement for P. falciparum intraerythrocytic growth. However, genomic analysis revealed the loss of FASII pathway components in B. bovis whereas the pathway is intact for P. falciparum but regulated to be expressed when needed (hepatic stages) and silent when not (intraerythrocytic stages). The results indicate specialized molding of apicoplast biosynthetic pathways to meet the requirements of individual apicomplexan parasites and their unique intracellular niches.


Assuntos
Proteína de Transporte de Acila/metabolismo , Babesia bovis/metabolismo , Oxirredutases/metabolismo , Babesia bovis/citologia , Babesia bovis/enzimologia , Inibidores Enzimáticos/farmacologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Organelas/enzimologia , Organelas/metabolismo , Organelas/ultraestrutura , Plasmodium falciparum/citologia , Plasmodium falciparum/enzimologia , Plasmodium falciparum/metabolismo , Transporte Proteico/efeitos dos fármacos
14.
Vet Parasitol ; 167(2-4): 196-204, 2010 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-19833439

RESUMO

Mini- and microsatellite sequences have proven to be excellent tools for the differentiation of strains and populations in several protozoan parasites due to their high variability. In the present work we have searched the genome of the tick-transmitted bovine hemoprotozoon Babesia bovis for tandem repeats (TRs) that could be useful for a multilocus typing system. Hundred and nineteen sequences were shortlisted and tested in five common B. bovis reference isolates originating from distinct geographic locations of North and South America: Texas, USA (T2Bo), Mexico (RAD and Mo7), and Santa Fe and Salta, Argentina (R1A and S2P, respectively). Satellite sequences were PCR-amplified using specific primers, separated by polyacrylamide gel electrophoresis, visualized by silver staining and sized. Fourteen TR sequences could be reliably amplified in all isolates and displayed length polymorphism. All primers used were specific for B. bovis and did not amplify genomic DNA from the bovine host or from Babesia bigemina, the principal co-infecting bovine parasite in the Americas, allowing their future use in field surveys. The 14 satellite markers identified are distributed throughout the four chromosomes of B. bovis as follows: chromosome 1 (n=3), chromosome 2 (n=2), chromosome 3 (n=5), and chromosome 4 (n=4). Within the five B. bovis isolates we identified nine satellite marker loci with two alleles, three with three alleles, one with four and another with five alleles. In comparison to Theileria parva, a bovine hemoprotozoan that pertains to the same piroplasmida order and own a genome of similar size, the number of polymorphic TRs and the average number of alleles per TR locus seem to be significantly reduced in the B. bovis genome. Furthermore, the ratio of micro- to minisatellites in both B. bovis and T. parva is considerably lower than in other eukaryotes, as confirmed by bioinformatic analysis. The multilocus genotype of the five B. bovis isolates was assessed and the genetic distance between each other determined followed by cluster analysis based on neighbor joining. The resulting phenogram showed that B. bovis isolates segregated into three clusters according to their geographic origin. The presented marker system is suitable to explore various parameters of B. bovis populations such as genetic diversity, infection dynamics and their structure under different epidemiological situations, which are of crucial importance for improved control strategies.


Assuntos
Babesia bovis/genética , Babesiose/veterinária , Doenças dos Bovinos/parasitologia , Sequências de Repetição em Tandem/genética , Animais , Argentina/epidemiologia , Babesiose/epidemiologia , Babesiose/parasitologia , Bovinos , Doenças dos Bovinos/epidemiologia , México/epidemiologia , Texas/epidemiologia
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