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1.
Talanta ; 237: 122962, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34736687

RESUMEN

Paper-based biosensor is one of the most commonly used platforms for point-of-care testing (POCT). Among these platforms, microfluidic paper-based analytical devices (µPADs) have the most versatile designs due to the different hydrophobic barrier patterns and layers of the devices. In addition, µPADs can also be used in combination with other biosensor platforms to improve the performance of the device. Simple and convenient methods for fabricating low-cost and design-adjustable hydrophobic barriers on paper are one of the most challenging aspects for creating µPADs. This work demonstrated a simple technique for using the common polylactic acid (PLA) filament and wax filament to create hydrophobic barriers on paper for µPADs using a commercialized 3D printer. As a proof of concept, the papers with 3D printed PLA barrier were used in combination with a fluidic chip in a prototype biosensor, in which the barrier paper housed four cell-free reactions and the fluidic chip achieved sample delivery to the reactions in the device. Our designed prototype was capable of discriminating dengue virus serotypes based on small nucleotide sequence differences. The proposed combination of 3D-printed barrier paper and fluidic chip provides a versatile platform for rapid prototyping of POCT with possible compatibility with various detection systems.


Asunto(s)
Técnicas Biosensibles , Virus del Dengue , Papel , Sistemas de Atención de Punto , Impresión Tridimensional , Serogrupo
2.
Int J Food Microbiol ; 361: 109473, 2022 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-34768041

RESUMEN

The epidemiological characteristics of Salmonella spp. in pork have been widely studied in China, but the results remain inconsistent. This study aimed to summarize the epidemiological characteristics of Salmonella spp. isolated from pork, including its prevalence, serovar distribution, and antibiotic resistance rate. We systematically reviewed published studies on Salmonella spp. isolated from pork in China between 2000 and 2020 in two Chinese and three English databases and quantitatively summarized its prevalence, serovar distribution, and antibiotic resistance using meta-analysis methods. Furthermore, we conducted subgroup analysis and meta-regression to explore the source of the heterogeneity from historical changes and regional difference perspectives. Ninety-one eligible studies published between 2000 and 2020 were included. The meta-analysis showed that the pooled prevalence of Salmonella isolated from pork was 0.17 (95% CI: 0.14, 0.20), with a detected growing trend over time. For the proportions of serovars, Derby (0.32, 95% CI: 0.26, 0.38), Typhimurium (0.10, 95% CI: 0.07, 0.15) and London (0.05, 95% CI: 0.03, 0.08) were dominant in these studies. The antibiotic resistance rates were high for tetracycline (0.68, 95% CI: 0.59, 0.77), sulfisoxazole (0.65, 95% CI: 0.45, 0.83), ampicillin (0.43, 95% CI: 0.34, 0.53), streptomycin (0.42, 95% CI: 0.29, 0.56), and sulfamethoxazole (0.42, 95% CI: 0.25, 0.60). The results of this study revealed a high prevalence, the regional characteristics of serovar distribution, and the severe challenges of antibiotic resistance of Salmonella originating from pork in China, suggesting the potential increasing risk and disease burden. Therefore, it is necessary to improve the prevention and control strategies of Salmonella in pork.


Asunto(s)
Carne de Cerdo , Carne Roja , Animales , China/epidemiología , Farmacorresistencia Microbiana , Pruebas de Sensibilidad Microbiana , Prevalencia , Salmonella , Serogrupo , Porcinos
3.
Ann Lab Med ; 42(2): 268-273, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-34635618

RESUMEN

Salmonella is one of the major causes of food-borne infections. We investigated the serotype distribution and antimicrobial resistance of Salmonella isolates collected in Korea between January 2016 and December 2017. In total, 669 Salmonella isolates were collected from clinical specimens at 19 university hospitals. Serotyping was performed according to the Kauffmann-White scheme, and antimicrobial susceptibility was tested using Sensititre EUVSEC plates or disk diffusion. Among the strains, C (39.8%) and B (36.6%) were the most prevalent serogroups. In total, 51 serotypes were identified, and common serotypes were S. enterica serovar I 4,[5],12:i:- (16.7%), S. Enteritidis (16.1%), S. Bareilly (14.6%), S. Typhimurium (9.9%), and S. Infantis (6.9%). The resistance rates to ampicillin, chloramphenicol, and trimethoprim-sulfamethoxazole were 32.6%, 12.1%, and 8.4%, respectively. The resistance rates to cefotaxime and ciprofloxacin were 8.1% and 3.0%, respectively, while 5.4% were multidrug-resistant. S. enterica serovar I 4,[5],12:i:- and S. Enteritidis were highly prevalent, and there was an increase in rare serotypes. Multidrug resistance and ciprofloxacin resistance were highly prevalent. Periodic investigations of Salmonella serotypes and antimicrobial resistance are needed.


Asunto(s)
Antibacterianos , Farmacorresistencia Bacteriana , Antibacterianos/farmacología , Humanos , República de Corea , Salmonella/genética , Serogrupo
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 266: 120438, 2022 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-34627016

RESUMEN

Trans-urocanic acid (t-UCA) is an important epidermal UV protector predominantly found in human skin. Exposure of UV radiation triggers photoisomerization of t-UCA into its other conformer, cis-urocanic acid (cis-UCA), which has been shown to be a mediator of UV-induced immune-suppression leading to skin cancer. In this report, we present the investigation of molecular changes of t-UCA under high pressures by in-situ high pressure Raman spectroscopy. The study indicates onset of ring opening polymerization of t-UCA at pressure above 1.4 GPa. At pressures beyond 5 GPa, a well discernible characteristic vibrational mode (CC stretch) accompanied by several other spectral features such as δ CO2- and δ NH modes of cis-UCA point towards the isomerization of residual t-UCA monomers into cis-UCA. The content of cis-UCA gradually increased with increase in pressure. On release to ambient conditions, the spectrum of the quenched sample showed Raman modes of polymer and cis-UCA indicating that the changes are irreversible.


Asunto(s)
Ácido Urocánico , Humanos , Serogrupo , Piel , Espectrometría Raman , Rayos Ultravioleta
5.
Arch Razi Inst ; 76(3): 507-519, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34824744

RESUMEN

Multidrug-resistant (MDR) Salmonella serovars are considered a significant threat to veterinary and public health. Developing new antimicrobial compounds that can treat the infection caused by these notorious pathogens is a big challenge. Bacteriophages can be adsorbed on and inhibit the growth of bacteria, providing optimal and promising alternatives to chemical antimicrobial compounds against foodborne pathogens due to their abundance in nature and high host specificity. The objective of the current study was to isolate and characterize new phages from poultry farms and sewage and to evaluate their efficacy against S. Enteritidis isolates. The study reports three lytic phages designated as ϕSET1, ϕSET2, and ϕSET3 isolated from poultry carcasses and sewage samples in Qalubiya governorate Egypt. The effectiveness of phages was evaluated against multidrug-resistant S. Enteritidis strains. Electron microscopy showed that these phages belong to the Siphoviridae family. Phages were tested against 13 bacterial strains to determine their host range. They could infect four S. Enteritidis and one S. Typhimurium; however, they did not infect other tested bacterial species, indicating their narrow infectivity. The bacteriophage's single-step growth curves revealed a latent period of 20 min for ϕSET1 and 30 min for ϕSET2 and ϕSET3. The isolated Salmonella phages prevented the growth of S. Enteritidis for up to 18 hrs. The findings revealed that Salmonella phages could be used as alternative natural antibacterial compounds to combat infection with MDR S. Enteritidis in the poultry industry and represent a step forward to using large panels of phages for eliminating Salmonella from the food chain.


Asunto(s)
Bacteriófagos , Aves de Corral , Animales , Egipto , Granjas , Salmonella enteritidis , Serogrupo
6.
Zhonghua Liu Xing Bing Xue Za Zhi ; 42(3): 549-554, 2021 Mar 10.
Artículo en Chino | MEDLINE | ID: mdl-34814428

RESUMEN

Objective: To investigate the serotypes and antimicrobial resistance of seven invasive non-typhoidal Salmonella (iNTS) isolates. Methods: For 7 iNTS strains collected, serotype identification, antimicrobial susceptibility testing and whole genome sequencing were performed. We identified, annotated and analyzed the serotypes, MLST types, and antimicrobial resistance genes. Results: Among the 7 tested iNTS isolates, we found one Salmonella Typhimurium strain and two Salmonella Ⅰ 4, [5], 12: i:- strains whose MLST types were ST34, two Salmonella Enteritidis strains, one Salmonella Corvallis strain and one strain of unknown serotype with the antigenic formulae of Ⅰ 4, [5], 12: d:- (ST279 type). Six of seven strains were monophasic and the deletion or pseudogenization of Salmonella Flagellum gene might contribute to the enhancement of Salmonella invasiveness. None was found to be resistant to tigarcycline, aztreonam, amikacin, cephalosporins and carbapenem and one Salmonella Typhimurium strain was found to be co-resistant to eight classes of antimicrobials at the same time. Resistance genes were generally in accord with relative resistant phenotypes. Conclusion: The iNTS strains could show high level multi-drug resistance, indicating that close attention should be paid to the resistance of iNTS though the overall resistance might be relatively not high.


Asunto(s)
Infecciones por Salmonella , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Farmacorresistencia Bacteriana/genética , Humanos , Pruebas de Sensibilidad Microbiana , Tipificación de Secuencias Multilocus , Salmonella typhimurium/genética , Serogrupo
7.
Zhonghua Liu Xing Bing Xue Za Zhi ; 42(5): 878-885, 2021 May 10.
Artículo en Chino | MEDLINE | ID: mdl-34814482

RESUMEN

Objective: Analyze epidemiological situation of dengue fever,and survey impacts of four serotypes dengue viruses in Guangzhou, 2019. Methods: Information of patients was collected in Notifiable Infectious Disease Report System (NIDRS). Spatial autocorrelation of dengue cases was evaluated using ArcGIS version 10.2. Serum samples were tested by real-time PCR. Virus strains were isolated from positive sera. Then E gene was sequenced. Phylogenetic trees were including PhyMLsoftwarev 3.1. Results: A total of 1 655 dengue cases, consisted of 1 382 local cases and 273 imported cases, was confirmed in 2019. The incidence was 11.10 per 100 000 dengue cases were autocorrelated in Guangzhou. There were 18 high-high clusters. Most of the imported dengue cases were imported from Southeast Asian countries (86.08%,235/273) and African countries (2.56%,7/273). Of 749 serum samples detected by real-time PCR, the positive rate was 93.06% (697/749). Four hundred and sixty-four dengue virus strains had been isolated in 2019. Compared with data from the genotype tree of the former years, no genotype shift was discovered. Serotype 1 was still predominant. Serotype 2 was the significant strain in Baiyun district and Liwan district. Conclusions: Dengue fever was spreading all over Guangzhou in 2019. The suburban areas, which played a more critical role in causing the spread and outbreak of dengue fever, should be given more prominence. Inspection at ports should be enforced to prevent importing cases from African countries and Southeast Asian countries. The risk of serotype 2 cannot be overlooked. Four serotypes dengue viruses prevailed simultaneously in Guangzhou, which warns us to take precaution of severe dengue outbreaks.


Asunto(s)
Virus del Dengue , Dengue , China/epidemiología , Dengue/epidemiología , Virus del Dengue/genética , Brotes de Enfermedades , Genotipo , Humanos , Epidemiología Molecular , Filogenia , Serogrupo , Análisis Espacial
8.
Zhonghua Liu Xing Bing Xue Za Zhi ; 42(6): 1037-1043, 2021 Jun 10.
Artículo en Chino | MEDLINE | ID: mdl-34814503

RESUMEN

Objective: To understand the epidemiological and etiologic characteristics of meningococcal meningitis in Xinjiang Uygur Autonomous Region (Xinjiang). Methods: The epidemiological data about the meningococcal meningitis cases in Xinjiang from 1960 to 2019 were collected from the China information system for disease control and prevention and the Center for Disease Control and Prevention of Xinjiang. The epidemiological characteristics were analyzed. Clinical specimens from suspected cases were cultured and tested by real-time PCR method. A survey on the carriage rate of Neisseria meningitides (Nm) in the healthy population was performed. The serogroups of isolates were determined by serum-agglutination and PCR methods. Multi-locus sequence typing was used for subtyping the isolates. Results: The incidence rates of meningococcal meningitis in Xinjiang from 1960 to 2019 were 0.02/100 000-81.32/100 000, with the mortality as 1.05%-20.78%. The five districts with the most cases were Kashi prefecture, Aksu prefecture, Urumqi city, Changji Hui autonomous prefecture, and Hotan prefecture. Before 1990, serogroup A (81.82%) was the commonest group for cases and contacts. After 1990, 14.00% of the cases were caused by serogroups B, C, W, and Y. There was no predominant serogroup for contacts with serogroups B, C, W, Y, and C accounting for 23.28%, 18.53%, 15.52%, 9.91% and 7.33% respectively. The general Nm carriage rate was 15.50%, with the population of 16 - 20 years age group having the highest rate (25.53%). Serogroups B (52.11%), W (20.66%), C (12.21%), and Y (9.39%) occupied 52.11%, 20.66%, 12.21% and 9.39% respectively. The commonest clonal lineages of Nm isolates were ST-4821, ST-175, and ST-5 clonal complexes, while the ST-5 and ST-4821 clonal complexes were the major ones for invasive strains. Conclusions: There appeared regional differences in the incidence rates of Xinjiang meningococcal meningitis, and the carriage rate of Nm was high. The serogroups have been changing. It is necessary to strengthen the prevention and control of meningococcal meningitis to prevent any potential outbreak.


Asunto(s)
Meningitis Meningocócica , Infecciones Meningocócicas , Neisseria meningitidis , Brotes de Enfermedades , Humanos , Meningitis Meningocócica/epidemiología , Tipificación de Secuencias Multilocus , Neisseria meningitidis/genética , Serogrupo
9.
BMC Infect Dis ; 21(1): 1129, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34724923

RESUMEN

BACKGROUND: We describe the serotype distribution of Streptococcus agalactiae (GBS) carriage isolates from women in labor and among GBS isolates causing invasive infections during the same period to see if the distribution of carriage serotypes reflects the GBS serotypes causing invasive diseases including early-onset disease (EOGBS). METHODS: Data on invasive isolates from 2019 including serotype, erythromycin and clindamycin susceptibility was retrieved from the Danish national reference laboratory, Statens Serum Institut. Carriage isolates were collected from women with risk factors for EOGBS enrolled at delivery at the maternity ward at a Danish University Hospital, first half of 2019. RESULTS: Among carriage isolates, the dominant serotype was IX (21 %) followed by serotype III (19 %). The resistance to erythromycin and clindamycin was 21 and 26 %, respectively. Among invasive GBS isolates, no case of EOGBS with serotype IX was detected but the distribution of serotypes were otherwise similar to the GBS carrier strains. The corresponding resistance to erythromycin and clindamycin was 23 and 15 %, respectively. Penicillin resistance was not detected among carriage nor invasive isolates. CONCLUSIONS: The distribution of serotypes among carriage and invasive GBS reflects the assumption that EOGBS occur following transmission of GBS from mother to newborn, with the exception of serotype IX.


Asunto(s)
Infecciones Estreptocócicas , Streptococcus agalactiae , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Dinamarca/epidemiología , Farmacorresistencia Bacteriana , Femenino , Humanos , Recién Nacido , Pruebas de Sensibilidad Microbiana , Embarazo , Mujeres Embarazadas , Factores de Riesgo , Serogrupo , Infecciones Estreptocócicas/tratamiento farmacológico , Infecciones Estreptocócicas/epidemiología
10.
Front Cell Infect Microbiol ; 11: 744742, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34765566

RESUMEN

In our community-based prospective cohort study in young children, we observed a significant increase in pneumococcal serotype 35B nasopharyngeal (NP) commensal colonization during the 2011-2014 timeframe, but these strains were not associated with disease. Beginning in 2015 and continuing through to the present, the serotype 35B virulence changed, and it became the dominant bacteria isolated and associated with pneumococcal acute otitis-media (AOM) in our cohort. We performed comparative analyses of 250 35B isolates obtained from 140 children collected between 2006 and 2019. Changes in prevalence, clonal-complex composition, and antibiotic resistance were analyzed. Seventy-two (29%) of 35B isolates underwent whole-genome sequencing to investigate genomic changes associated with the shift in virulence that resulted in increased rates of 35B-associated AOM disease. 35B strains that were commensals and AOM disease-causing were mainly associated with sequence type (ST) 558. Antibiotic concentrations of ß-lactams and ofloxacin necessary to inhibit growth of 35B strains rose significantly (2006-2019) (p<0.005). However, only isolates from the 35B/ST558 showed significant increases in MIC50 of penicillin and ofloxacin between the years 2006-2014 and 2015-2019 (p=0.007 and p<0.0001). One hundred thirty-eight SNPs located in 34 different genes were significantly associated with post-2015 strains. SNPs were found in nrdG (metal binding, 10%); metP and metN (ABC transporter, 9%); corA (Mg2+ transporter, 6%); priA (DNA replication, 5%); and on the enzymic gene ldcB (LD-carboxypeptidase, 3%). Pneumococcal serotype 35B strains was a common NP commensal during 2010-2014. In 2015, a shift in increasing number of AOM cases occurred in young children caused by 35B, that was associated with changes in genetic composition and antibiotic susceptibility.


Asunto(s)
Otitis Media , Infecciones Neumocócicas , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Niño , Preescolar , Humanos , Lactante , Infecciones Neumocócicas/tratamiento farmacológico , Infecciones Neumocócicas/epidemiología , Vacunas Neumococicas , Estudios Prospectivos , Serogrupo , Serotipificación , Streptococcus pneumoniae/genética
11.
BMC Res Notes ; 14(1): 417, 2021 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-34794506

RESUMEN

OBJECTIVE: Neisseria meningitidis is a Gram-negative bacterium that causes meningitis. N. meningitidis serogroup W (NmW) capsule polymerase synthesizes capsular polysaccharide of this serogroup. This enzyme could be a tool for meningococcal glycoconjugate vaccine development. Our long-term goal is to control activity of the NmW capsule polymerase for production of defined carbohydrates for vaccines. The enzyme lacks a simple, high-throughput activity assay. Here, we describe the use of high-throughput bioluminescence assays (CMP-Glo and UDP-Glo by Promega) to investigate NmW capsule polymerase activity. These assays detect free nucleotides produced during transfer of sugar from UDP-Galactose and CMP-Sialic Acid to an acceptor. Kinetic studies using NmW hydrolyzed polysaccharide (PS) acceptor are described as well as preliminary work with a sialic acid trimer (DP3) acceptor. RESULTS: In CMP-Glo kinetic studies, with constant donor (80 µM) and varied NmW hydrolyzed polysaccharide (0-2000 µg/mL), a Km of 629.2 ± 101.4 µg/mL and a Vmax of 0.8965 ± 0.05823 µM/min was obtained. Using UDP-Glo, Km and Vmax values of 13.84 ± 9.675 µM and 0.6205 ± 0.1331 µM/min were obtained with varied CMP-NeuNAc (0-80 µM) and constant acceptor (400 µg/mL) and UDP-Gal (80 µM). This is the first report of using bioluminescence assays for NmW kinetics.


Asunto(s)
Vacunas Meningococicas , Neisseria meningitidis , Cinética , Serogrupo , Transferasas
12.
Front Cell Infect Microbiol ; 11: 726740, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34796125

RESUMEN

Background: Streptococcus pneumoniae is an important pathogen causing high morbidity and high mortality in children and undergoes frequent recombination for capsule switching to neutralize the 13-valent pneumococcal conjugate vaccine (PCV13). This study aimed to investigate the prevalence, and molecular characteristics including serotypes and antibiotic susceptibility of S. pneumoniae isolated from children living in Southwest China from 2017 to 2019 to facilitate the selection of effective vaccine formulations and appropriate antibiotic treatment regimens. Methods: This study was conducted at West China Second University Hospital (Chengdu, Sichuan Province, China), Zunyi Medical University Third Affiliated Hospital/First People's Hospital of Zunyi (Zunyi, Guizhou Province, China) and Chengdu Jinjiang District Maternal and Child Healthcare Hospital (Chengdu, Sichuan Province, China). Demographic and clinical characteristics of children infected with S. pneumoniae were collected and analysed. Next-generation sequencing and sequence analysis were used to determine the serotypes, sequence types, antibiotic resistance and potential protein vaccine target genes of the pneumococcal isolates. The coverage rate provided by PCV13 was estimated by calculating the percentage of the specific serotypes that were specifically the PCV13-included serotypes. Antimicrobial susceptibility was determined by the microdilution broth method. Results: The most prevalent pneumococcal serotypes were 19F (25.8%), 19A (14.1%), 6B (12.5%), 6A (9.4%) and 14 (7.8%). The predominant STs were ST271 (23.3%), ST320 (15.5%) and ST90 (8.6%), dominated by the clonal complex Taiwan19F-14 (39.1%). The coverage rate of PCV13 was 77.3% in all the isolates, with relatively higher values in invasive isolates (86.4%). Over the decade, the rates of resistance to penicillin, amoxicillin and cefotaxime were 5.6%, 5.3% and 5.1%, respectively, with significantly higher values in invasive isolates (22.4%, 14.9% and 11.9%). Almost all the isolates were resistant to erythromycin (99.1%) and clindamycin (95.9%). All isolates carried virulence-related genes, including ply, psaA, piaA, piuA, phtE, nanA, pepO, danJ, pvaA, clpP, pcsB, stkP, potD, and strH. The carriage of virulence and resistance genes varied among serotypes and clades, with serotype 19F/ST271 showing higher resistance to antibiotics and being more likely to carry pilus genes and other virulence genes. Conclusion: These data provide valuable information for the understanding of pneumococcal pathogenesis, antimicrobial resistance and the development of protein-based vaccines against pneumococcal infection.


Asunto(s)
Infecciones Neumocócicas , Streptococcus pneumoniae , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Niño , China/epidemiología , Humanos , Lactante , Pruebas de Sensibilidad Microbiana , Tipificación de Secuencias Multilocus , Infecciones Neumocócicas/tratamiento farmacológico , Infecciones Neumocócicas/epidemiología , Vacunas Neumococicas , Serogrupo , Streptococcus pneumoniae/genética
13.
Epidemiol Infect ; 149: e178, 2021 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-34635196

RESUMEN

In October 2019, public health surveillance systems in Scotland identified an increase in the number of reported infections of Shiga toxin-producing Escherichia coli (STEC) O26:H11 involving bloody diarrhoea. Ultimately, across the United Kingdom (UK) 32 cases of STEC O26:H11 stx1a were identified, with the median age of 27 years and 64% were male; six cases were hospitalised. Among food exposures there was an association with consuming pre-packed sandwiches purchased at outlets belonging to a national food chain franchise (food outlet A) [odds ratio (OR) = 183.89, P < 0.001]. The common ingredient identified as a component of the majority of the sandwiches sold at food outlet A was a mixed salad of Apollo and Iceberg lettuce and spinach leaves. Microbiological testing of food and environmental samples were negative for STEC O26:H11, although STEC O36:H19 was isolated from a mixed salad sample taken from premises owned by food outlet A. Contamination of fresh produce is often due to a transient event and detection of the aetiological agent in food that has a short-shelf life is challenging. Robust, statistically significant epidemiological analysis should be sufficient evidence to direct timely and targeted on-farm investigations. A shift in focus from testing the microbiological quality of the produce to investigating the processes and practices through the supply chain and sampling the farm environment is recommended.


Asunto(s)
Brotes de Enfermedades , Infecciones por Escherichia coli/epidemiología , Comida Rápida/microbiología , Enfermedades Transmitidas por los Alimentos/epidemiología , Escherichia coli Shiga-Toxigénica/aislamiento & purificación , Adulto , Diarrea/epidemiología , Diarrea/microbiología , Monitoreo Epidemiológico , Infecciones por Escherichia coli/microbiología , Comida Rápida/envenenamiento , Comida Rápida/provisión & distribución , Femenino , Enfermedades Transmitidas por los Alimentos/microbiología , Genoma Bacteriano/genética , Humanos , Masculino , Ensaladas/microbiología , Ensaladas/envenenamiento , Ensaladas/provisión & distribución , Serogrupo , Toxina Shiga/genética , Escherichia coli Shiga-Toxigénica/genética , Reino Unido/epidemiología
14.
BMC Infect Dis ; 21(1): 1082, 2021 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-34670495

RESUMEN

Plasma leakage is a precursor to life-threatening complications of dengue, but this group is poorly defined and not often reported in literature. Patients with Dengue haemorrhagic fever (DHF) as defined in the 1997 World Health Organization classification are often reported, and they all have plasma leakage, but some patients with plasma leakage do not meet the definition of DHF. The study aims to estimate the frequency of plasma leakage and DHF (as a surrogate of plasma leakage) in dengue and its variations based on virus serotype, geography, patient gender and pre-existing immunity to dengue. PUBMED, Scopus, EMBASE, CINAHL and Web of Science were searched for prospective observational studies reporting on plasma leakage or DHF. Quality of data was assessed using the NIH quality assessment tool for cohort studies. Forty-three studies that recruited 15,794 confirmed dengue patients were eligible. Cumulative frequency of plasma leakage was 36.8% (15 studies, 1642/4462, 95% CI 35.4-38.2%), but surprisingly the estimated cumulative frequency of DHF was higher (45.7%, 32 studies, 4758/10417, 95% CI 44.7-46.6%), indicating that current medical literature over-reports DHF or under-reports plasma leakage. Therefore, a reliable estimate for the proportion of dengue patients developing plasma leakage cannot be derived from existing medical literature even after applying rigorous inclusion criteria to select homogenous studies. Plasma leakage is an important marker of "at-risk" dengue patients and standardizing its definition, diagnosis and reporting should be a priority in research and global policy.


Asunto(s)
Dengue Grave , Humanos , Estudios Prospectivos , Serogrupo , Dengue Grave/epidemiología , Organización Mundial de la Salud
15.
Front Cell Infect Microbiol ; 11: 673299, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34676175

RESUMEN

Dengue fever (DF) is a mosquito-borne viral disease caused by the dengue virus (DENV), which is considered one of the most important arboviruses in the world. This study aimed to determine the molecular, epidemiological, and phylogenetic characterization of 174 DENV-1 (132 indigenous cases and 42 imported cases) isolated from nine municipalities of Zhejiang province in 2019. The analyses of phylogenetics, haplotypes, and amino acid substitutions were conducted based on the full envelope (E) gene sequences. Sixty-four haplotypes were clustered into two main clades, with isolates from Wenzhou and Taizhou mainly clustered into clade I and Hangzhou and Ningbo cases clustered into clade II. Six sites of amino acid substitutions including A88T, F96L, M297V, T339S, I378L, and V436I were only observed in strains isolated from Ningbo and Hangzhou, while two sites of amino acid substitutions including V312L and V380I were observed in strains from Taizhou and Wenzhou. In our study, strains were in high homology with the strains from Southeast Asian countries, thus cases in Zhejiang were probably imported from Southeast Asian countries. The strains from different regions in Zhejiang were clustered in the same branch which may be caused by the continuous import of cases in the same country at different time periods. After the continuous outbreak in Zhejiang province, some sites of the dengue gene have mutated, and the effects need further study.


Asunto(s)
Virus del Dengue , Dengue , Animales , China/epidemiología , Dengue/epidemiología , Virus del Dengue/genética , Brotes de Enfermedades , Genotipo , Filogenia , Serogrupo
16.
Epidemiol Mikrobiol Imunol ; 70(3): 168-177, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34641691

RESUMEN

AIM: Presentation of the first results of the analysis of Neisseria meningitidis isolates from invasive meningococcal disease and from clinically and/or epidemiologically linked cases from 2010-2019. Whole genome sequencing (WGS) was used for the study. MATERIAL AND METHODS: The study set included 59 isolates of N. meningitidis from 2010-2019. Serogrouping was done by conventional serological methods and confirmed by RT-PCR. WGS was used for detailed molecular characterization, covering not only basic genes but also ribosomal and capsular genes, antibiotic resistance gene penA, and outer membrane protein gene porA. RESULTS: WGS analysis of N. meningitidis isolates resulted in a detailed molecular characterization. In a large part of the genes analysed, new mutated allelic variants were found. They were submitted to the PubMLST database and subsequently annotated by the curator. All 59 study isolates were assigned to BAST types, characterized by a unique combination of allelic variants of N. meningitidis B vaccine (MenB vaccine) antigen genes. Overall, 32 different BAST types were identified, and 10 isolates either carried an unknown combination of BAST loci or a new allelic variant in some of the BAST loci. Furthermore, the MenDeVAR index, which provides information on the functional effect of MenB vaccines on a given isolate, was determined. CONCLUSIONS: The results obtained add to the body of knowledge of the transmission of invasive and non-invasive strains of N. meningitidis in the population. The WGS analysis provided detailed data on the coverage of these strains by new MenB vaccines.


Asunto(s)
Infecciones Meningocócicas , Neisseria meningitidis , República Checa/epidemiología , Humanos , Infecciones Meningocócicas/epidemiología , Neisseria meningitidis/genética , Serogrupo , Secuenciación Completa del Genoma
17.
Vet Res ; 52(1): 135, 2021 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-34674760

RESUMEN

Glaesserella parasuis (G. parasuis) is a commensal bacterium in the upper respiratory tract of pigs that can also cause the swine Glässer disease, which induces an intensive inflammatory response and results in significant economic losses to the swine industry worldwide. G. parasuis can cause disease through infection of the respiratory tract, resulting in systemic infection, but the mechanism is largely unknown. Recently we showed that Glaesserella parasuis serotype 4 (GPS4) increased swine tracheal epithelial barrier permeability, resulting in easier bacterial translocation. Tight junction proteins (TJ) play a crucial role in maintaining the integrity and impermeability of the epithelial barrier. GPS4 decreased the expression of the TJ ZO-1 and occludin in swine tracheal epithelial cells (STEC). Furthermore, the proinflammatory cytokines IL-6, IL-8 and TNF-α were significantly upregulated in GPS4-infected STEC, and both the MAPK and NF-κB signaling pathways were activated and contributed to the expression of TNF-α. We demonstrate that the production of proinflammatory cytokines, especially TNF-α, during GPS4 infection was involved in barrier dysfunction. Additionally, animal challenge experiments confirmed that GPS4 infection downregulated TJ in the lungs of piglets and induced a severe inflammatory response. In general, G. parasuis infection downregulated the expression of TJ and induced massive secretion of proinflammatory cytokines, resulting in epithelial barrier disruption and favoring bacterial infection. This study allowed us to better understand the mechanism by which G. parasuis crosses the respiratory tract of pigs.


Asunto(s)
Traslocación Bacteriana , Haemophilus parasuis/fisiología , Infecciones por Pasteurellaceae/veterinaria , Transducción de Señal , Enfermedades de los Porcinos/microbiología , Animales , Células Epiteliales , Infecciones por Haemophilus/microbiología , Infecciones por Haemophilus/fisiopatología , Infecciones por Haemophilus/veterinaria , Haemophilus parasuis/genética , Infecciones por Pasteurellaceae/microbiología , Infecciones por Pasteurellaceae/fisiopatología , Serogrupo , Sus scrofa , Porcinos , Enfermedades de los Porcinos/fisiopatología
18.
J Infect Public Health ; 14(11): 1603-1611, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34624714

RESUMEN

BACKGROUND: Rhinoviruses (RV) are associated with the development and exacerbations of asthma and chronic obstructive pulmonary disease. They've also been linked to more severe diseases like pneumonia, acute bronchiolitis, croup, and otitis media. Because of the hypervariable sequences in the same serotypes, no effective vaccine against rhinoviruses has been developed to date. With the availability of new full-length genome sequences for all RV-A and RV-B serotyped strains, this study used bioinformatics to find a suitable RV strain with the highest similarity matrices to the other strains. METHODS: The full genomic sequences of all known different RV-A and -B prototypes were downloaded from the National Centre for Biotechnology Information (NCBI) and divided into minor low-density lipoprotein receptor (LDLR) and major intercellular adhesion molecule groups (ICAM). The sequences were edited using Biological Sequence Alignment Editor, v 7.2.0 (BioEdit software) to study each capsid protein (VP1, VP2, VP3, and VP4) and analyzed using the EMBL-EBI ClustalW server and the more current Clustal Omega tool for the calculation of the identities and similarities. RESULTS: We analyzed and predicted immunogenic motifs from capsid proteins that are conserved across distinct RV serotypes using a bioinformatics technique. The amino acid sequences of VP3 were found to be the most varied, while VP4 was the most conserved protein among all RV-A and RV-B strains. Among all strains studied, RV-74 demonstrated the highest degree of homology to other strains and could be a potential genetic source for recombinant protein production. Nine highly conserved regions with a minimum length of 9-mers were identified, which could serve as potential immune targets against rhinoviruses. CONCLUSION: Therefore, bioinformatics analysis conducted in the current study has paved the way for the selection of immunogenic targets. Bioinformatically, the ideal strain's capsid protein is suggested to contain the most common RVs immunogenic sites.


Asunto(s)
Asma , Proteínas de la Cápside , Rhinovirus , Proteínas de la Cápside/genética , Moléculas de Adhesión Celular , Biología Computacional , Humanos , Receptores de LDL , Rhinovirus/genética , Serogrupo
19.
Arch Microbiol ; 203(10): 5907-5919, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34647141

RESUMEN

Listeria monocytogenes is a pathogenic bacterium present in several environments able to survive and proliferate in food processing plants, contaminating products that when ingested can lead to listeriosis. Worldwide, the bacterium has been isolated from foods of animal and plant origin and its occurrence in ready-to-eat foods is a challenge for food processing establishments. Serotypes 1/2a, 1/2b, 1/2c, and 4b related to 95% of listeriosis cases have been detected in different foods and presented resistance to common antibiotics such as tetracycline and penicillin. The analysis and dissemination of the presence of L. monocytogenes in different foods are essential to anchor control and prevention measures. In Brazil, despite the lack of official data on contamination by L. monocytogenes, some studies have reported the presence of bacteria in various foods and food processing environments. Thus, this review focuses on presenting the main characteristics of the L. monocytogenes, resistance to antimicrobial agents, and occurrence in several foods and countries from 2010 to 2020.


Asunto(s)
Listeria monocytogenes , Listeriosis , Animales , Manipulación de Alimentos , Microbiología de Alimentos , Listeriosis/epidemiología , Listeriosis/prevención & control , Serogrupo
20.
Int J Food Microbiol ; 360: 109439, 2021 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-34688125

RESUMEN

Salmonella enterica displaying resistance to extended-spectrum cephalosporins and fluoroquinolone (FQs) has been deemed a high-priority pathogen by the World Health Organization (WHO). While CTX-M type acquired ß-lactamases have been detected in S. enterica serovar Bovismorbificans, DHA enzymes have been rarely reported in S. Bovismorbificans. In this study, we here report for the first time the isolation of two multi-drug resistant (MDR) S. Bovismorbificans strains co-harboring plasmid-encoded AmpC (pAmpC) ß-lactamase gene (blaDHA-1) and qnrB gene, 16Sal017 isolated from a chicken meat sample and 16Sal018 from a grass carp fish sample, collected from retail markets in Guangzhou, China. The blaDHA-1 and qnrB genes in these two strains were both located on the same novel 217,773 bp IncHI2 plasmid belonged to ST2. The plasmid contained 16 additional acquired antimicrobial resistance genes encoding resistance to eight antibiotic classes and quaternary ammonium compound. Besides, 16Sal017 contained an additional 10,124 bp Col (pHAD28)-like plasmid harboring qnrS1. The blaDHA-1 and qnrB4 genes were located in an 18,198 bp region, sul1-qacEΔ1-ampR-blaDHA-1-pspABCDF-qnrB4-sapABC-IS91-sul1-qacEΔ1, which has been identified in various bacteria species, indicating the high transfer ability of blaDHA-1 and qnrB4 genes within this gene cluster. The IncHI2 plasmid was found to be transferable to Escherichia coli J53 by conjugation and resulted in the acquiring of multiple resistance in the transconjugants. Genome sequence comparisons by cgMLST and MAUVE alignment indicated 16Sal017 and 16Sal018 are highly similar and are not epidemiologically linked with strains from other sources and countries. Our findings suggest S. Bovismorbificans as a new host for conjugative mega-plasmid harboring blaDHA-1 and qnrB4 genes, and highlight the potential transmission opportunity of these S. Bovismorbificans clones through the food chain, which need continuous investigation.


Asunto(s)
Salmonella enterica , Salmonella , Animales , Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple/genética , Pruebas de Sensibilidad Microbiana , Plásmidos/genética , Salmonella enterica/genética , Serogrupo , beta-Lactamasas/genética
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