RESUMO
Metal halide perovskites hold great potential for next-generation light-emitting diodes (PeLEDs). Despite significant progress, achieving high-performance PeLEDs hinges on optimizing the interface between the perovskite crystal film and the charge transport layers, especially the buried interface, which serves as the starting point for perovskite growth. Here, we develop a bottom-up perovskite film modulation strategy using formamidine acetate (FAAc) to enhance the buried interface. This multifaceted approach facilitates the vertical-oriented growth of high-quality perovskites with minimized defects. Meanwhile, the in situ deprotonation between FA+ and ZnO could eliminate the hydroxyl (-OH) defects and modulate the energy level of ZnO. The resulting FAPbI3-PeLED exhibits a champion EQE of 23.84% with enhanced operational stability and suppressed EQE roll-off. This strategy is also successfully extended to other mixed-halide PeLEDs (e.g., Cs0.17FA0.83Pb(I0.75Br0.25)3), demonstrating its versatility as an efficient and straightforward method for enhancing the PeLEDs' performance.
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A 1D/2D genome-wide association study strategy was adopted to investigate the genetic systems underlying the reciprocal adaptation of rice (Oryza sativa) and its bacterial pathogen, Xanthomonas oryzae pv. oryzae (Xoo) using the whole-genome sequencing and large-scale phenotyping data of 701 rice accessions and 23 diverse Xoo strains. Forty-seven Xoo virulence-related genes and 318 rice quantitative resistance genes (QR-genes) mainly located in 41 genomic regions, and genome-wide interactions between the detected virulence-related genes and QR genes were identified, including well-known resistance genes/virulence genes plus many previously uncharacterized ones. The relationship between rice and Xoo was characterized by strong differentiation among Xoo races corresponding to the subspecific differentiation of rice, by strong shifts toward increased resistance/virulence of rice/Xoo populations and by rich genetic diversity at the detected rice QR-genes and Xoo virulence genes, and by genome-wide interactions between many rice QR-genes and Xoo virulence genes in a multiple-to-multiple manner, presumably resulting either from direct protein-protein interactions or from genetic epistasis. The observed complex genetic interaction system between rice and Xoo likely exists in other crop-pathogen systems that would maintain high levels of diversity at their QR-loci/virulence-loci, resulting in dynamic coevolutionary consequences during their reciprocal adaptation.
Assuntos
Interações Hospedeiro-Patógeno/genética , Oryza/genética , Oryza/microbiologia , Xanthomonas/genética , Adaptação Fisiológica/genética , Resistência à Doença/genética , Regulação Bacteriana da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genoma Bacteriano , Genoma de Planta , Estudo de Associação Genômica Ampla , Desequilíbrio de Ligação , Filogenia , Melhoramento Vegetal , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Polimorfismo de Nucleotídeo Único , Virulência/genética , Sequenciamento Completo do Genoma , Xanthomonas/patogenicidadeRESUMO
BACKGROUND: Management of inferior ramus of the pubis-ischium ramus remains controversial, and related research is sparse. The main intention of this study is to describe the biomechanical and clinical outcomes of pubis-ischium ramus fractures in Tile B pelvic injuries and to identify the feasibility and necessity of fixation of the inferior ramus of the pubis-ischium ramus. METHODS: This study comprised two parts: a biomechanical test and a retrospective clinical study. For the biomechanical tests, Tile B-type pelvic injuries were modeled in six cadaver specimens by performing pubis-ischium osteotomies and disruption of the anterior and interosseous sacroiliac ligaments. The superior and/or inferior rami of the pubis-ischium ramus were repaired with reconstruction plates and separated into three groups (A, B, and C). Specimens were placed in the standing position and were loaded axially with two-leg support for three cycles at 500 N. The displacements of sacroiliac joints at osteotomy were measured with Vernier calipers and compared using statistical software. To investigate the clinical outcomes of this technique, 26 patients were retrospectively analyzed and divided into a superior ramus fixation group (Group D) and a combined superior and inferior ramus of the pubis-ischium ramus fixation group (Group E). The main outcome measures were time of operation, blood loss, postoperative radiographic reduction grading, and functional outcomes. RESULTS: In the vertical loading test, Group E showed better pelvic ring stability than Group D (P < 0.05). However, the shift of the sacroiliac joints was almost identical among the three groups. In our clinical case series, all fractures in Group E achieved bony union. Group E demonstrated earlier weight-bearing functional exercise (2.54 ± 1.45 vs 4.77 ± 2.09; P = 0.004), earlier bony union (13.23 ± 2.89 vs 16.55 ± 3.11; P = 0.013), and better functional outcomes (89.77 ± 7.27 vs 82.38 ± 8.81; P = 0.028) than Group D. The incidence of sexual dysfunction was significantly lower in Group E than that in Group D (2/13 vs 7/13; P = 0.039). Bone nonunion occurred in two patients in Group D, and two patients in Group E had heterotopic ossification. None of the patients exhibited wound complications, infections, implant failures, or bone-implant interface failures. CONCLUSIONS: Fixation of the inferior ramus of a pubis-ischium ramus fracture based on conventional fixation of the anterior pelvic ring is mechanically superior in cadaveric Tile B pelvic injury and shows rapid recovery, good functional outcomes, and low incidence of complications.
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Placas Ósseas , Ossos Pélvicos , Humanos , Fenômenos Biomecânicos , Masculino , Feminino , Adulto , Ossos Pélvicos/cirurgia , Ossos Pélvicos/lesões , Ossos Pélvicos/diagnóstico por imagem , Pessoa de Meia-Idade , Fenômenos Mecânicos , Cadáver , Fraturas Ósseas/cirurgia , Estudos Retrospectivos , Fixação Interna de Fraturas/instrumentaçãoRESUMO
The study was conducted to determine the proportion and concentration of enterohemorrhagic Escherichia coli (EHEC) O157 and six non-O157 (O26, O45, O103, O111, O121, and O145) serogroups and identify seasonal and processing plant differences in feces and on hides of cull dairy cattle processed in commercial slaughterhouses in the United States. Approximately 60 rectal and 60 hide-on samples from matched carcasses were collected in each of three processing plants, in two periods; summer of 2017 and spring of 2018. Samples before enrichment were spiral plated to quantify EHEC, and postenriched samples underwent culture methods that included immuno-magnetic separation, plating on selective media, and PCR assays for identification and serogroup confirmation of putative isolates. An isolate was considered EHEC O157 positive if it harbored serogroup-specific (rfbE), Shiga toxin (stx1 and/or stx2), and intimin (eae) genes and EHEC non-O157 positive if at least one of the non-O157 serogroup-specific, stx1 and/or stx2, and eae genes was identified. Generalized linear mixed models were fitted to estimate overall proportion of positives for EHEC O157 and non-O157 EHEC serogroups, as well as seasonal and processing plant differences in fecal and hide-on proportion of positives. The fecal EHEC proportion at the sample level was 1.8% (95% CI = 0.0-92.2%) and 4.2% (95% CI = 0.0-100.0%) for EHEC O157 and EHEC non-O157, respectively. Hide sample level proportion of positives was 3.0% (95% CI = 0.0-99.9%) for EHEC O157 and 1.6% (95% CI = 0.0-100.0%) for EHEC non-O157. The proportion of EHEC O157 and non-O157 significantly differed by processing plant and sample type (hide vs. feces), but not by season. The association between proportion of EHEC serogroups in feces with the proportion on hides collected from matched cattle was 7.8% (95% CI = 0.6-53.3%) and 3.8% (95% CI = 0.3-30.8%) for EHEC O157 and non-O157, respectively. Taken together, our findings provide evidence of a low proportion of EHEC serogroups in the feces and on hides of cull dairy cattle and that their proportion varies across processing plants.
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BACKGROUND: Soil water and organic carbon (C) are key factors affecting the growth and development of apple seedlings. The objective of the study was to investigate the effects of different soil moisture and glucose supplies on apple seedling growth and soil enzyme activities. We hypothesized that the growth of apple seedlings was affected by soil water and C content through their effects on root structure, plant physiological properties and soil enzymatic activities. A pot experiment consisting of nine treatments was set up, including three water treatments with soil moisture contents at 75-85% (normal irrigation, CK), 65-75% (light water stress, LS), and 55-65% (mild water stress, MS) of the soil field capacity, in combination with three glucose treatments with carbon/nitrogen (C/N) ratio of 7.5 (C1, no adding glucose), 10 (C2) and 15 (C3), respectively. RESULTS: Results showed that the LSC2 treatment significantly increased plant height by 7%, stem diameter by 5% and leaf area by 17%, as compared with LSC1. Also, LSC2 significantly increased root dry weight, root vitality and soil enzyme activities. Moreover, results of leaf photosynthetic, malondialdehyde (MDA), peroxidase (POD), superoxide dismutase (SOD) and proline contents also proved that adding glucose improved the drought resistance of plants. CONCLUSION: LSC2 treatment is more conducive to the growth of apple seedlings, and application of carbon has a good alleviation effect on plant water stress. The study demonstrated that addition of exogenous glucose alleviated light water deficiency, significantly affected root vitality, and promoted apple seedling growth. © 2024 Society of Chemical Industry.
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Growing resistant rice cultivars is the most effective strategy to control bacterial blight (BB), a devastating disease caused by Xanthomonas oryzae pv. oryzae (Xoo). Screening resistant germplasm and identifying resistance (R) genes are prerequisites for breeding resistant rice cultivars. We conducted a genome-wide association study (GWAS) to detect quantitative trait loci (QTL) associated with BB resistance using 359 East Asian temperate Japonica accessions inoculated with two Chinese Xoo strains (KS6-6 and GV) and one Philippine Xoo strain (PXO99A). Based on the 55K SNPs Array dataset of the 359 Japonica accessions, eight QTL were identified on rice chromosomes 1, 2, 4, 10, and 11. Four of the QTL coincided with previously reported QTL, and four were novel loci. Six R genes were localized in the qBBV-11.1, qBBV-11.2, and qBBV-11.3 loci on chromosome 11 in this Japonica collection. Haplotype analysis revealed candidate genes associated with BB resistance in each QTL. Notably, LOC_Os11g47290 in qBBV-11.3, encoding a leucine-rich repeat receptor-like kinase, was a candidate gene associated with resistance to the virulent strain GV. Knockout mutants of Nipponbare with the susceptible haplotype of LOC_Os11g47290 exhibited significantly improved BB resistance. These results will be useful for cloning BB resistance genes and breeding resistant rice cultivars.
Assuntos
Oryza , Xanthomonas , Estudo de Associação Genômica Ampla , Oryza/genética , Oryza/microbiologia , Genes de Plantas , Melhoramento Vegetal , Locos de Características Quantitativas , Bactérias/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Resistência à Doença/genéticaRESUMO
Shiga toxin-producing E. coli (STEC) are major foodborne pathogens. While many studies have focused on the "top-7 STEC", little is known for minor serogroups. A total of 284 non-top-7 STEC strains isolated from cattle feces were subjected to whole-genome sequencing (WGS) to determine the serotypes, the presence of virulence genes and antimicrobial resistance (AMR) determinants. Nineteen typeable and three non-typeable serotypes with novel O-antigen loci were identified. Twenty-one AMR genes and point mutations in another six genes that conferred resistance to 10 antimicrobial classes were detected, as well as 46 virulence genes. The distribution of 33 virulence genes and 15 AMR determinants exhibited significant differences among serotypes (p < 0.05). Among all strains, 81.7% (n = 232) and 14.1% (n = 40) carried stx2 and stx1 only, respectively; only 4.2% (n = 12) carried both. Subtypes stx1a, stx1c, stx2a, stx2c, stx2d, and stx2g were identified. Forty-six strains carried eae and stx2a and therefore had the potential cause severe diseases; 47 strains were genetically related to human clinical strains inferred from a pan-genome phylogenetic tree. We were able to demonstrate the utility of WGS as a surveillance tool to characterize the novel serotypes, as well as AMR and virulence profiles of uncommon STEC that could potentially cause human illness.
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Doenças dos Bovinos/microbiologia , Farmacorresistência Bacteriana , Infecções por Escherichia coli/veterinária , Escherichia coli Shiga Toxigênica/isolamento & purificação , Animais , Antibacterianos/farmacologia , Bovinos , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Fezes/microbiologia , Filogenia , Sorogrupo , Escherichia coli Shiga Toxigênica/efeitos dos fármacos , Escherichia coli Shiga Toxigênica/genética , Escherichia coli Shiga Toxigênica/patogenicidade , Virulência , Sequenciamento Completo do GenomaRESUMO
Shiga toxin-producing Escherichia coli (STEC) are major foodborne pathogens and seven serogroups, O26, O45, O103, O111, O121, O145, and O157, often called top-7 STEC, account for the majority of the STEC-associated human illnesses in the United States. Two Shiga toxins, Shiga toxins 1 and 2, encoded by stx1 and stx2 genes, are major virulence factors that are involved in STEC infections. Foodborne STEC infections have been linked to a variety of foods of both animal and plant origin, including products derived from cereal grains. In recent years, a few STEC outbreaks have been linked to contaminated wheat flour. The microbiological quality of the wheat grains is a major contributor to the safety of wheat flour. The objective of the study was to utilize polymerase chain reaction (PCR)- and culture-based methods to detect and isolate STEC in wheat grains. Wheat grain samples (n = 625), collected from different regions of the United States, were enriched in modified buffered peptone water with pyruvate (mBPWp) or E. coli (EC) broth, and they were then subjected to PCR- and culture-based methods to detect and isolate STEC. Wheat grains enriched in EC broth yielded more samples positive for stx genes (1.6% vs. 0.32%) and STEC serogroups (5.8% vs. 2.4%) than mBPWp. The four serogroups of top-7 detected and isolated were O26, O45, O103, and O157 and none of the isolates was positive for the Shiga toxin genes. A total of five isolates that carried the stx2 gene were isolated and identified as serogroups O8 (0.6%) and O130 (0.2%). The EC broth was a better medium to enrich wheat grains than mBPWp for the detection and isolation of STEC. The overall prevalence of virulence genes and STEC serogroups in wheat grains was low. The stx2-positive serogroups isolated, O8 and O130, are not major STEC pathogens and have only been implicated in sporadic infections in animals and humans.
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Infecções por Escherichia coli , Proteínas de Escherichia coli , Escherichia coli Shiga Toxigênica , Animais , Infecções por Escherichia coli/epidemiologia , Proteínas de Escherichia coli/genética , Fezes , Farinha , Humanos , Reação em Cadeia da Polimerase Multiplex , Escherichia coli Shiga Toxigênica/genética , Triticum , Estados Unidos/epidemiologiaRESUMO
Escherichia coli serogroups O157, O26, O45, O103, O111, O121, and O145, when carrying major virulence genes, the Shiga toxin genes stx1 and stx2 and the intimin gene eae, are important foodborne pathogens. They are referred to as the "top 7" Shiga toxin-producing E. coli (STEC) serogroups and were declared by the USDA as adulterants to human health. Since top 7 serogroup-positive cattle feces and ground beef can also contain nonadulterant E. coli strains, regular PCR cannot confirm whether the virulence genes are carried by adulterant or nonadulterant E. coli serogroups. Thus, traditional gold-standard STEC detection requires bacterial isolation and characterization, which are not compatible with high-throughput settings and often take a week to obtain a definitive result. In this study, we demonstrated that the partition-based multichannel digital PCR (dPCR) system can be used to detect and associate the E. coli serogroup-specific gene with major virulence genes and developed a single-cell-based dPCR approach for rapid (within 1 day) and accurate detection and confirmation of major STEC serogroups in high-throughput settings. Major virulence genes carried by each of the top 7 STEC serogroups were detected by dPCR with appropriately diluted intact bacterial cells from pure cultures, culture-spiked cattle feces, and culture-spiked ground beef. Furthermore, from 100 randomly collected, naturally shed cattle fecal samples, 3 O103 strains carrying eae and 2 O45 strains carrying stx1 were identified by this dPCR assay and verified by the traditional isolation method. This novel and rapid dPCR assay is a culture-independent, high-throughput, accurate, and sensitive method for STEC detection and confirmation.
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Reação em Cadeia da Polimerase/métodos , Toxina Shiga I/genética , Toxina Shiga II/genética , Escherichia coli Shiga Toxigênica/isolamento & purificação , Análise de Célula Única/métodos , Fatores de Virulência/genética , Animais , Bovinos , DNA Bacteriano , Proteínas de Escherichia coli/genética , Fezes/microbiologia , Microbiologia de Alimentos , Genes Bacterianos , Carne/microbiologia , Antígenos O/genética , Sorogrupo , Toxina Shiga , Escherichia coli Shiga Toxigênica/genéticaRESUMO
The objective of this study was to quantify the frequency, distribution, and variability of fecal shedding and super-shedding of Shiga toxin-producing Escherichia coli (STEC) serogroups O26, O45, O103, O111, O121, O145, and O157 in feedlot cattle over time. A total of 750 fecal grab samples were collected over a 5-week period (June-July 2017) from 150 cattle housed in 10 pens at a commercial feedlot operation. Samples were subjected to culture-based methods and real-time quantitative polymerase chain reaction for STEC detection and quantification. Cumulative animal-level prevalence estimates were 9.5%, 5.2%, and 15.8% for STEC O157, non-O157 STEC serogroups only (STEC-6), and for all STEC serogroups tested (STEC-7), respectively, with the prevalence of STEC O157 and STEC-7 significantly differing between weeks (p < 0.01). Most of the variability in fecal shedding for STEC O157, STEC-6, and STEC-7 was between pens, rather than between cattle. Over the 5-week period, 10 animals (6.7%) persistently shed STEC non-O157 over 3 or more consecutive weeks, whereas 2 animals (1.3%) intermittently shed STEC non-O157 on nonconsecutive weeks. Fifteen animals (10.0%) shed multiple STEC serogroups within the same fecal sample and five animals (3.3%) shed multiple serogroups at super-shedding levels, higher than 104 CFU (colony-forming units)/g, in the same sample. The presence of a super-shedder in a pen was significantly associated with a greater within pen-level prevalence of STEC-6 (p = 0.01). This study gives further insights into intermittent and persistent shedding and super-shedding patterns of STEC serogroups in individual feedlot cattle, which can enable the development and effective application of preharvest and periharvest interventions, as well as surveillance strategies, for these pathogens.
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Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Fezes/microbiologia , Escherichia coli Shiga Toxigênica/isolamento & purificação , Animais , Derrame de Bactérias , Bovinos , Contagem de Colônia Microbiana , DNA Bacteriano , Infecções por Escherichia coli/veterinária , Proteínas de Escherichia coli/genética , Feminino , Microbiologia de Alimentos , Estudos Longitudinais , Masculino , Prevalência , Reação em Cadeia da Polimerase em Tempo Real , Sorogrupo , Toxina Shiga/genética , Escherichia coli Shiga Toxigênica/classificação , Escherichia coli Shiga Toxigênica/genética , Estados Unidos/epidemiologiaRESUMO
Shiga toxin-producing Escherichia coli (STEC) are major foodborne pathogens and seven serogroups, O26, O45, O103, O111, O121, O145, and O157, that account for the majority of the STEC-associated illness in humans. Similar to cattle, swine also harbor STEC and shed them in the feces and can be a source of human STEC infections. Information on the prevalence of STEC in swine feces is limited. Therefore, our objective was to utilize polymerase chain reaction (PCR) assays to determine prevalence of major virulence genes and serogroups of STEC. Fecal samples (n = 598), collected from finisher pigs within 3 weeks before marketing in 10 pig flows located in 8 states, were included in the study. Samples enriched in E. coli broth were subjected to a real-time PCR assay targeting three virulence genes, Shiga toxin 1 (stx1), Shiga toxin 2 (stx2), and intimin (eae), which encode for Shiga toxins 1 and 2, and intimin, respectively. A novel PCR assay was designed and validated to detect serogroups, O8, O20, O59, O86, O91, O100, O120, and O174, previously reported to be commonly present in swine feces. In addition, enriched fecal samples positive for Shiga toxin genes were subjected to a multiplex PCR assay targeting O26, O45, O103, O104, O111, O121, O145, and O157 serogroups implicated in human clinical infections. Of the 598 fecal samples tested by real-time PCR, 25.9%, 65.1%, and 67% were positive for stx1, stx2, and eae, respectively. The novel eight-plex PCR assay indicated the predominant prevalence of O8 (88.6%), O86 (35.5%), O174 (24.1%), O100 (20.2%), and O91 (15.6%) serogroups. Among the seven serogroups relevant to human infections, three serogroups, O121 (17.6%), O157 (14%), and O26 (11%) were predominant. PCR-based detection indicated high prevalence of Shiga toxin genes and serogroups that are known to carry Shiga toxin genes, including serogroups commonly prevalent in cattle feces and implicated in human infections and in edema disease in swine.
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Toxina Shiga/genética , Escherichia coli Shiga Toxigênica/isolamento & purificação , Sus scrofa/microbiologia , Animais , Estudos Transversais , Fezes/microbiologia , Genes Bacterianos , Reação em Cadeia da Polimerase Multiplex/veterinária , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Sorogrupo , Escherichia coli Shiga Toxigênica/genética , Estados UnidosRESUMO
Campylobacter spp. can be pathogenic to humans and often harbor antimicrobial resistance genes. Data on resistance in relation to fluoroquinolone use in beef cattle are scarce. This cross-sectional study of preharvest cattle evaluated Campylobacter prevalence and susceptibility to nalidixic acid and ciprofloxacin in feedlots that previously administered a fluoroquinolone as primary treatment for bovine respiratory disease. Twenty fresh fecal samples were collected from each of 10 pens, in each of five feedlots, 1-2 weeks before harvest. Feces were cultured for Campylobacter using selective enrichment and isolation methods. Genus and species were confirmed via PCR. Minimum inhibitory concentrations (MICs) of ciprofloxacin and nalidixic acid were determined using a micro-broth dilution method and human breakpoints. Antimicrobial use within each pen was recorded. Data were analyzed using generalized linear mixed-models (prevalence) and survival analysis (MICs). Overall, sample-level prevalence of Campylobacter was 27.2% (272/1000) and differed significantly among feedlots (p < 0.01). Campylobacter coli was the most common species (55.1%; 150/272), followed by Campylobacter hyointestinalis (42.6%; 116/272). Within-pen prevalence was not significantly associated with the number of fluoroquinolone treatments, sex, body weight, or metaphylaxis use, but was associated with the number of days cattle were in the feedlot (p = 0.03). The MICs for the majority of Campylobacter isolates were above the breakpoints for nalidixic acid (68.4%; 175/256) and for ciprofloxacin (65.6%; 168/256). Distributions of MICs for nalidixic acid (p ≤ 0.01) and ciprofloxacin (p ≤ 0.05) were significantly different among feedlots, and by Campylobacter species. However, fluoroquinolone treatments, sex, body weight, days on feed, and metaphylaxis were not significantly associated with MIC distributions within pens. We found no evidence that the number of fluoroquinolone treatments within feedlot pens significantly affected the within-pen fecal prevalence or quinolone susceptibilies of Campylobacter in feedlots that used a fluoroquinolone as primary treatment for bovine respiratory disease.
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Antibacterianos/uso terapêutico , Infecções por Campylobacter/veterinária , Campylobacter/efeitos dos fármacos , Doenças dos Bovinos/epidemiologia , Enrofloxacina/uso terapêutico , Quinolonas/farmacologia , Animais , Antibacterianos/farmacologia , Campylobacter/isolamento & purificação , Infecções por Campylobacter/tratamento farmacológico , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/microbiologia , Bovinos , Doenças dos Bovinos/tratamento farmacológico , Doenças dos Bovinos/microbiologia , Estudos Transversais , Farmacorresistência Bacteriana , Kansas/epidemiologia , Prevalência , Texas/epidemiologiaRESUMO
OBJECTIVE: To detect potential variation in glutaryl-CoA dehydrogenase (GCDH) gene among three Chinese families affected with glutaric acidemia type â (GA-1) and correlate the genotypes with phenotypes. METHODS: Genomic DNA was extracted from peripheral blood samples derived from three patients with GA-1 and their family members. The coding regions of the GCDH gene were amplified with PCR and subjected to Sanger sequencing. RESULTS: The clinical manifestation of the patients varied from macrocephaly to severe encephalopathy, with notable phenotypic difference between siblings carrying the same variation. In pedigrees 1 and 2, the probands have carried compound heterozygous variations c.1133C>T(p.Ala378Val) and c.1244-2A>C, which were derived their fathers and mothers, respectively. In pedigree 3, the proband has carried compound heterozygous variation c.339delT (p.Tyr113) and c.406G>T (p.Gly136Cys). Among these, variations c.339delT and c.1133C>T were verified as novel by retrieval of dsSNP, HGMD and 1000 genome database. Bioinformatic analysis suggested that above variations can affect protein function and are probably pathogenic. CONCLUSION: Above discovery has expanded the mutation spectrum of the GCDH gene. No correlation was found between the clinical phenotype and genotype of GA-1 patients.
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Erros Inatos do Metabolismo dos Aminoácidos/diagnóstico , Erros Inatos do Metabolismo dos Aminoácidos/genética , Encefalopatias Metabólicas/diagnóstico , Encefalopatias Metabólicas/genética , Glutaril-CoA Desidrogenase/deficiência , Glutaril-CoA Desidrogenase/genética , China , Análise Mutacional de DNA , Humanos , MutaçãoRESUMO
The study objective was to determine effects of fluoroquinolone metaphylaxis on fecal prevalence of Salmonella and Campylobacter and fecal prevalence of quinolone-resistant Salmonella and Campylobacter in feedlot cattle. On Day 0, cattle (n = 288) at risk for bovine respiratory disease (BRD) were randomly assigned to either a nontreated control pen (12 pens) or a fluoroquinolone-treated (enrofloxacin; Baytril® 100) pen (12 pens). Rectal fecal samples were collected from cattle on days 0, 7, 14, 21, and 28. Feces were cultured for Salmonella enterica and Campylobacter spp. using enrichment and selective isolation methods, and confirmed by serology and PCR. Susceptibilities to nalidixic acid and ciprofloxacin were determined using microbroth dilution methods. Data analyses were performed using linear mixed models. Overall, Salmonella sp. and Campylobacter spp. were recovered from 10.2% (139/1,364) and 12.4% (170/1,364) of the fecal samples, respectively. Campylobacter species included hyointestinalis, jejuni, and coli. Neither Salmonella sp. nor Campylobacter spp. prevalence was significantly impacted by fluoroquinolone treatment (p = 0.80, p = 0.61, respectively). However, Salmonella prevalence differed between study weeks (p < 0.01) with prevalence decreasing over time. Before treatment, 98.9% (91/92) of Salmonella isolates were susceptible to nalidixic acid and ciprofloxacin. All Salmonella recovered posttreatment (n = 43) were susceptible to both antimicrobials. The majority of Campylobacter spp. recovered before treatment were resistant to nalidixic acid (23/35; 65.7%) and ciprofloxacin (21/35; 60.0%). There was no significant treatment by week interaction (p = 0.85) or treatment effects (p = 0.61) on the posttreatment prevalence of Campylobacter resistance. There was, however, a significant week effect (p = 0.05), with Campylobacter resistance prevalence decreasing over time. In this 28-day study, we found no evidence that a fluoroquinolone used for metaphylaxis significantly impacts fecal prevalence of Salmonella sp. or Campylobacter spp. or the fecal prevalence of nalidixic acid or ciprofloxacin resistance.
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Infecções por Campylobacter/veterinária , Campylobacter/efeitos dos fármacos , Doenças dos Bovinos/epidemiologia , Doenças Transmitidas por Alimentos/prevenção & controle , Salmonelose Animal/epidemiologia , Salmonella enterica/efeitos dos fármacos , Animais , Anti-Infecciosos/farmacologia , Campylobacter/isolamento & purificação , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/microbiologia , Bovinos , Doenças dos Bovinos/microbiologia , Farmacorresistência Bacteriana , Fezes/microbiologia , Fluoroquinolonas/farmacologia , Doenças Transmitidas por Alimentos/microbiologia , Humanos , Testes de Sensibilidade Microbiana , Prevalência , Quinolonas/farmacologia , Distribuição Aleatória , Salmonelose Animal/microbiologia , Salmonella enterica/isolamento & purificaçãoRESUMO
OBJECTIVE: To delineate the clinical features and potential mutation of the ATP7A gene in a family affected with Menkes disease. METHODS: Clinical data of a patient and his family members were analyzed. Sanger sequencing and multiplex ligation-dependent probe amplification (MLPA) assays were performed to detect the mutation of the ATP7A gene. RESULTS: The patient was admitted at the age of 5 months due to severe epilepsy and marked delayed psychomotor development. Significantly light complexion, pudgy cheeks and sparse fuzzy wooly hair were noted. Cranial magnetic resonance imaging and angiography revealed cortical atrophy, leukoencephalopathy and circuitous of intracranial vessels. The plasma ceruloplasmin was decreased. MLPA has identified a deletion spanning exons 8 to 12 of the ATP7A gene. His mother was found to be a heterozygous carrier of the same mutation. CONCLUSION: The clinical features and a novel mutation of the ATP7A gene of the family have been delineated.
Assuntos
Adenosina Trifosfatases/genética , Proteínas de Transporte de Cátions/genética , Síndrome dos Cabelos Torcidos/genética , Adulto , Povo Asiático/genética , China , ATPases Transportadoras de Cobre , Análise Mutacional de DNA , Éxons , Feminino , Heterozigoto , Humanos , Lactente , Masculino , Mutação , LinhagemRESUMO
Salmonella is an important foodborne pathogen and antimicrobial resistance can be a human health concern. The objectives of this cross-sectional study were to (1) determine the prevalence and quinolone susceptibility of Salmonella in feces of preharvest commercial feedlot cattle and (2) determine if the prevalence and susceptibility of Salmonella isolates were associated with previous fluoroquinolone use within pens. Five feedlots in western Kansas and Texas were selected based on their use of a commercially licensed fluoroquinolone for initial treatment of bovine respiratory disease (BRD). Twenty pen floor fecal samples were collected from each of 10 pens from each feedlot during early summer of 2012. Salmonella isolation was performed and microbroth dilution was used to determine susceptibility of isolates to nalidixic acid and ciprofloxacin. Prior antimicrobial treatment data were retrieved from feedlots' operational data. Generalized linear mixed models were used to assess associations between Salmonella prevalence and the number of fluoroquinolone treatments within pens while taking into consideration cattle demographic and management factors, as well as the hierarchical structure of the data. Overall, cumulative fecal prevalence of Salmonella was 38.0% (380/1000), but prevalence varied significantly (p < 0.01) among the five feedlots: 0.5% (1/200), 17.5% (35/200), 37.0% (74/200), 58.5% (117/200), and 76.5% (153/200). Salmonella serogroups included C1 (49.3%), E (36.4%), C2 (13.8%), and D (0.6%). There was no significant association (p = 0.52) between Salmonella prevalence and the frequency of fluoroquinolone treatments within a pen. All Salmonella isolates (n = 380) were susceptible to ciprofloxacin, while one isolate exceeded the human breakpoint (≥32 µg/mL) for nalidixic acid. In conclusion, Salmonella fecal prevalence in preharvest cattle was highly variable among feedlots. Nearly all Salmonella isolates were susceptible to quinolones, despite the fact that a fluoroquinolone was used as the primary therapeutic antimicrobial to treat BRD in these feedlot populations.
Assuntos
Doenças dos Bovinos/microbiologia , Fluoroquinolonas/farmacologia , Infecções Respiratórias/veterinária , Salmonelose Animal/microbiologia , Salmonella/efeitos dos fármacos , Matadouros , Criação de Animais Domésticos , Animais , Bovinos , Doenças dos Bovinos/tratamento farmacológico , Doenças dos Bovinos/epidemiologia , Estudos Transversais , Farmacorresistência Bacteriana , Fezes/microbiologia , Feminino , Fluoroquinolonas/uso terapêutico , Microbiologia de Alimentos , Kansas/epidemiologia , Masculino , Carne , Testes de Sensibilidade Microbiana/veterinária , Prevalência , Infecções Respiratórias/tratamento farmacológico , Salmonella/isolamento & purificação , Salmonelose Animal/tratamento farmacológico , Salmonelose Animal/epidemiologia , Texas/epidemiologiaRESUMO
The United States Department of Agriculture Food Safety and Inspection Service has declared seven Shiga toxin-producing Escherichia coli (STEC) serogroups (O26, O45, O103, O111, O121, O145, and O157) as adulterants in raw, nonintact beef products. The objective of this study was to determine the prevalence of these seven serogroups and the associated virulence genes (Shiga toxin [stx1, stx2], and intimin [eae]) in cattle feces during summer (June-August 2013) and winter (January-March 2014) months. Twenty-four pen floor fecal samples were collected from each of 24 cattle pens, in both summer and winter months, at a commercial feedlot in the United States. Samples were subjected to culture-based detection methods that included enrichment, serogroup-specific immunomagnetic separation and plating on selective media, followed by a multiplex polymerase chain reaction for serogroup confirmation and virulence gene detection. A sample was considered STEC positive if a recovered isolate harbored an O gene, stx1, and/or stx2, and eae genes. All O serogroups of interest were detected in summer months, and model-adjusted prevalence estimates are as follows: O26 (17.8%), O45 (14.6%), O103 (59.9%), O111 (0.2%), O121 (2.0%), O145 (2.7%), and O157 (41.6%); however, most non-O157 isolates did not harbor virulence genes. The cumulative model-adjusted sample-level prevalence estimates of STEC O26, O103, O145, and O157 during summer (n=576) were 1.0, 1.6, 0.8, and 41.4%, respectively; STEC O45, O111, and O121 were not detected during summer months. In winter, serogroups O26 (0.9%), O45 (1.5%), O103 (40.2%), and O121 (0.2%) were isolated; however, no virulence genes were detected in isolates from cattle feces collected during winter (n=576). Statistically significant seasonal differences in prevalence were identified for STEC O103 and O157 (p<0.05), but data on other STEC were sparse. The results of this study indicate that although non-O157 serogroups were present, non-O157 STEC were rarely detected in feces from the feedlot cattle populations tested in summer and winter months.
Assuntos
Fezes/microbiologia , Genes Bacterianos , Estações do Ano , Escherichia coli Shiga Toxigênica/isolamento & purificação , Animais , Bovinos/microbiologia , Contaminação de Alimentos , Microbiologia de Alimentos , Separação Imunomagnética , Reação em Cadeia da Polimerase Multiplex , Carne Vermelha/microbiologia , Escherichia coli Shiga Toxigênica/classificação , Escherichia coli Shiga Toxigênica/genética , Estados UnidosRESUMO
Several real-time polymerase chain reaction (PCR) assays have been developed to detect and quantify Shiga toxin-producing Escherichia coli (STEC) O157:H7, but none have targeted the O-antigen specific gene (rfbEO157) in combination with the three major virulence genes, stx1, stx2, and eae. Our objectives were to develop and validate a four-plex, quantitative PCR (mqPCR) assay targeting rfbE(O157), stx1, stx2, and eae for the detection and quantification of STEC O157 in cattle feces, and compare the applicability of the assay to detect STEC O157 to a culture method and conventional PCR (cPCR) targeting the same four genes. Specificity of the mqPCR assay to differentially detect the four genes was confirmed with strains of O157 and non-O157 STEC with different profiles of target genes. In cattle feces spiked with pure cultures, detection limits were 2.8×10(4) and 2.8×10(0) colony-forming units/g before and after enrichment, respectively. Detection of STEC O157 in feedlot cattle fecal samples (n=278) was compared between mqPCR, cPCR, and a culture method. The mqPCR detected 48.9% (136/278) of samples as positive for E. coli O157. Of the 100 samples that were randomly picked from 136 mqPCR-positive samples, 35 and 48 tested positive by cPCR and culture method, respectively. Of the 100 samples randomly chosen from 142 mqPCR-negative samples, all were negative by cPCR, but 21 samples tested positive by the culture method. McNemar's chi-square tests indicated significant disagreement between the proportions of positive samples detected by the three methods. In conclusion, the mqPCR assay that targets four genes is a novel and more sensitive method than the cPCR or culture method to detect STEC O157 in cattle feces. However, the use of real-time PCR as a screening method to identify positive samples and then subjecting only positive samples to a culture method may underestimate the presence of STEC O157 in fecal samples.
Assuntos
Adesinas Bacterianas/análise , Escherichia coli O157/genética , Proteínas de Escherichia coli/análise , Fezes/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Adesinas Bacterianas/genética , Animais , Carboidratos Epimerases/análise , Carboidratos Epimerases/genética , Bovinos , Escherichia coli O157/isolamento & purificação , Proteínas de Escherichia coli/genética , Toxina Shiga I/análise , Toxina Shiga I/genética , Toxina Shiga II/análise , Toxina Shiga II/genética , Transaminases/análise , Transaminases/genéticaRESUMO
OBJECTIVE: To review the clinical features of a families affected with glutaric acidemia type I (GA-1) and screen potential mutations in glutaryl-CoA dehydrogenase (GCDH) gene. METHODS: Clinical data of the patients and their family members was analyzed. Genomic DNA was extracted from peripheral blood samples. The 11 exons and flanking sequences of the GCDH gene were amplified with PCR and subjected to direct DNA sequencing. RESULTS: Two patients have manifested macrocephaly. Imaging analysis revealed arachnoid cyst and subdural effusion. The elder sister had encephalopathy crisis. The younger sister had significantly raised glutaric acid, whilst the elder sister was normal during the non-acute phase. Genetic analysis has revealed a homozygous c.1244-2A> C mutation of the GCDH gene in both patients. CONCLUSION: The clinical features and mutation of the GCDH gene have been delineated in a Chinese family affected with GA-1. The c.1244-2A> C mutation may be particularly common in the Chinese population.
Assuntos
Erros Inatos do Metabolismo dos Aminoácidos/genética , Encefalopatias Metabólicas/genética , Predisposição Genética para Doença/genética , Glutaril-CoA Desidrogenase/genética , Mutação , Adolescente , Erros Inatos do Metabolismo dos Aminoácidos/diagnóstico por imagem , Erros Inatos do Metabolismo dos Aminoácidos/enzimologia , Sequência de Bases , Encefalopatias Metabólicas/diagnóstico por imagem , Encefalopatias Metabólicas/enzimologia , China , Análise Mutacional de DNA , Saúde da Família , Feminino , Glutaril-CoA Desidrogenase/deficiência , Homozigoto , Humanos , Recém-Nascido , Imageamento por Ressonância Magnética , Masculino , RadiografiaRESUMO
Holstein steers (nâ =â 40; initial BWâ =â 84.9â ±â 7.1 kg) were used to study the genesis of liver abscesses (LA) using an acidotic diet challenge with or without intraruminal bacterial inoculation. Steers were housed in individual pens inside a barn and randomly assigned to one of three treatments: (1) low-starch control diet comprised primarily of dry-rolled corn and wet corn gluten feed (CON); (2) high-starch acidotic diet with steam-flaked corn (AD); or (3) acidotic diet plus intraruminal inoculation with Fusobacterium necrophorum subsp. necrophorum (9.8â ×â 108 colony forming units [CFU]/mL), Trueperella pyogenes (3.91â ×â 109 CFU/mL), and Salmonella enterica serovar Lubbock (3.07â ×â 108 CFU/mL), previously isolated from LA (ADB). Steers in AD and ADB were fed the acidotic diet for 3 d followed by 2 d of the CON diet, and this cycle was repeated four times. On day 23, ADB steers were intraruminally inoculated with the bacteria. At necropsy, gross pathology of livers, lungs, rumens, and colons was noted. Continuous data were analyzed via mixed models as repeated measures over time with individual steer as the experimental unit. Mixed models were also used to determine the difference in prevalence of necropsy scores among treatments. Ruminal pH decreased in AD and ADB steers during each acidotic diet cycle (Pâ ≤â 0.05). LA prevalence was 42.9% (6 of 14) in ADB vs. 0% in AD or CON treatments (Pâ <â 0.01). Ruminal damage was 51.1% greater in ADB than in AD (Pâ ≤â 0.04). Culture of LA determined that 100% of the abscesses contained F. necrophorum subsp. necrophorum, 0% contained T. pyogenes, 50% contained Salmonella, and 50% contained a combination of F. necrophorum subsp. necrophorum and Salmonella. The F. necrophorum subsp. necrophorum was clonally identical to the strain used for the bacterial inoculation based on phylogenetic analysis of the whole genome. This experimental model successfully induced rumenitis and LA in Holstein steers and confirms the central dogma of LA pathogenesis that acidosis and rumenitis lead to the entry of F. necrophorum into the liver to cause abscesses. Our findings suggest that an acidotic diet, in conjunction with intraruminal bacterial inoculation, is a viable model to induce LA. Further research is needed to determine the repeatability of this model, and a major application of the model will be in evaluations of novel interventions to prevent LA.
Liver abscesses (LA) in feedlots are costly to the beef industry. At harvest, LA cause an increase in liver condemnations, carcass trimming, and a decrease in quality grade. The objective of this research was to develop an experimental LA model in Holstein steers using an acidotic diet with and without intraruminal inoculation of bacteria involved in LA formation. These data suggest acidotic diet challenges in conjunction with bacterial inoculation were able to induce LA in Holstein steers. The acidotic diet alone caused reduced rumen content pH and caused rumen wall inflammation and damage, observed at harvest. Nonetheless, the addition of bacteria had a compounding effect on rumen damage. Both bacteria inoculated were isolated from 57% of LA suggesting they may work in synergy to form LA.