RESUMO
The synchronization between the speech envelope and neural activity in auditory regions, referred to as cortical tracking of speech (CTS), plays a key role in speech processing. The method selected for extracting the envelope is a crucial step in CTS measurement, and the absence of a consensus on best practices among the various methods can influence analysis outcomes and interpretation. Here, we systematically compare five standard envelope extraction methods the absolute value of Hilbert transform (absHilbert), gammatone filterbanks, heuristic approach, Bark scale, and vocalic energy), analyzing their impact on the CTS. We present performance metrics for each method based on the recording of brain activity from participants listening to speech in clear and noisy conditions, utilizing intracranial EEG, MEG and EEG data. As expected, we observed significant CTS in temporal brain regions below 10 Hz across all datasets, regardless of the extraction methods. In general, the gammatone filterbanks approach consistently demonstrated superior performance compared to other methods. Results from our study can guide scientists in the field to make informed decisions about the optimal analysis to extract the CTS, contributing to advancing the understanding of the neuronal mechanisms implicated in CTS.
Assuntos
Eletroencefalografia , Magnetoencefalografia , Percepção da Fala , Humanos , Percepção da Fala/fisiologia , Magnetoencefalografia/métodos , Eletroencefalografia/métodos , Feminino , Adulto , Masculino , Fala/fisiologia , Adulto Jovem , Córtex Auditivo/fisiologia , Eletrocorticografia/métodosRESUMO
BACKGROUND: Water is considered a source for the transmission of Arcobacter species to both humans and animals. This study was conducted to assess the prevalence, distribution, and pathogenicity of A. butzleri strains, which can potentially pose health risks to humans and animals. Cultures were isolated from surface waters of a mixed-use but predominately agricultural watershed in eastern Ontario, Canada. The detection of antimicrobial resistance (AMR) and virulence-associated genes (VAGs), as well as enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) assays were performed on 913 A. butzleri strains isolated from 11 agricultural sampling sites. RESULTS: All strains were resistant to one or more antimicrobial agents, with a high rate of resistance to clindamycin (99%) and chloramphenicol (77%), followed by azithromycin (48%) and nalidixic acid (49%). However, isolates showed a significantly (p < 0.05) high rate of susceptibility to tetracycline (1%), gentamycin (2%), ciprofloxacin (4%), and erythromycin (5%). Of the eight VAGs tested, ciaB, mviN, tlyA, and pldA were detected at high frequency (> 85%) compared to irgA (25%), hecB (19%), hecA (15%), and cj1349 (12%) genes. Co-occurrence analysis showed A. butzleri strains resistant to clindamycin, chloramphenicol, nalidixic acid, and azithromycin were positive for ciaB, tlyA, mviN and pldA VAGs. ERIC-PCR fingerprint analysis revealed high genetic similarity among strains isolated from three sites, and the genotypes were significantly associated with AMR and VAGs results, which highlight their potential environmental ubiquity and potential as pathogenic. CONCLUSIONS: The study results show that agricultural activities likely contribute to the contamination of A. butzleri in surface water. The findings underscore the importance of farm management practices in controlling the potential spread of A. butzleri and its associated health risks to humans and animals through contaminated water.
Assuntos
Arcobacter , Animais , Humanos , Arcobacter/genética , Canadá , Azitromicina , Clindamicina , Virulência , Ácido Nalidíxico/farmacologia , Cloranfenicol , EnterobacteriaceaeRESUMO
Non-baumannii Acinetobacter spp. are becoming more prevalent in clinical settings including those that present resistance to last-resort antibiotics such as colistin. AB222-IK40 is an Acinetobacter courvalinii strain isolated from the Ottawa Hospital Research Institute located in Ottawa, Canada. To our knowledge, it is the first report of clinical A. courvalinii in Canada. Based on the susceptibility profile, AB222-IK40 is resistant to colistin and non-susceptible to ertapenem. Whole-genome sequencing allowed for genomic investigation into colistin resistance mechanisms. No previously identified mechanism(s) were observed, but a mobile colistin resistance (mcr)-like gene and a UDP-glucose dehydrogenase gene were identified. Based on phylogenomic analyses, the mcr-like gene is an intrinsic phosphoethanolamine transferase. This gene family is implicated in one of the many mechanisms responsible for colistin resistance in Acinetobacter baumannii as well as Acinetobacter modestus. UDP-glucose dehydrogenase is involved in colistin resistance in Enterobacterales and has been shown to be involved in capsule formation in A. baumannii. Global lipidomics revealed greater abundance of phosphatidyl-myo-inositol and lyso-phosphatidyl ethanolamine moieties in the membrane of A. courvalinii than in A. baumannii. Lipidomic profiles showed differences that were probably responsible for the colistin resistance phenotype in AB222-IK40. This isolate was also hypervirulent based on survival assays in Galleria mellonella. As this is the first report of A. courvalinii from a hospital in Canada, this species may be an emerging clinical pathogen, and therefore, it is important to understand this mechanism of its colistin resistance and hypervirulence.
RESUMO
The Acinetobacter calcoaceticus-baumannii (ACB) complex is an often-overlooked group of nosocomial pathogens with a significant environmental presence. Rapid molecular screening methods for virulence, antimicrobial resistance, and toxin (VAT) genes are required to investigate the potential pathogenicity of environmental isolates. This study aimed to develop and apply novel ACB complex-specific multiplex PCR (mPCR) primers and protocols for the rapid detection of eight VAT genes. We optimized three single-tube mPCR assays using reference DNA from ACB complex and other Acinetobacter species. These assays were then applied to detect VAT genes in cultured ACB complex isolates recovered from clinical and environmental sources. Widespread detection of VAT genes in environmental isolates confirmed the validity, functionality, and applicability of these novel assays. Overall, the three newly developed ACB complex species-specific mPCR assays are rapid and simple tools that can be adopted in diagnostic and clinical lab settings. The detection of VAT genes in environmental isolates suggests that environmental niches could serve as a reservoir for potentially pathogenic ACB complex and warrants further investigation. The newly developed mPCR assays are specific, sensitive, and efficient, making them well-suited for high-throughput screening in epidemiological studies and evaluating the potential pathogenicity of ACB complex recovered from various sources.
Assuntos
Acinetobacter baumannii , Acinetobacter calcoaceticus , Toxinas Biológicas , Reação em Cadeia da Polimerase Multiplex/métodos , Virulência/genética , Antibacterianos/farmacologia , Acinetobacter calcoaceticus/genética , Farmacorresistência Bacteriana , Acinetobacter baumannii/genéticaRESUMO
BACKGROUND: The freshwater microbiome regulates aquatic ecological functionality, nutrient cycling, pathogenicity, and has the capacity to dissipate and regulate pollutants. Agricultural drainage ditches are ubiquitous in regions where field drainage is necessary for crop productivity, and as such, are first-line receptors of agricultural drainage and runoff. How bacterial communities in these systems respond to environmental and anthropogenic stressors are not well understood. In this study, we carried out a three year study in an agriculturally dominated river basin in eastern Ontario, Canada to explore the spatial and temporal dynamics of the core and conditionally rare taxa (CRT) of the instream bacterial communities using a 16S rRNA gene amplicon sequencing approach. Water samples were collected from nine stream and drainage ditch sites that represented the influence of a range of upstream land uses. RESULTS: The cross-site core and CRT accounted for 5.6% of the total number of amplicon sequence variants (ASVs), yet represented, on average, over 60% of the heterogeneity of the overall bacterial community; hence, well reflected the spatial and temporal microbial dynamics in the water courses. The contribution of core microbiome to the overall community heterogeneity represented the community stability across all sampling sites. CRT was primarily composed of functional taxa involved in nitrogen (N) cycling and was linked to nutrient loading, water levels, and flow, particularly in the smaller agricultural drainage ditches. Both the core and the CRT were sensitive responders to changes in hydrological conditions. CONCLUSIONS: We demonstrate that core and CRT can be considered as holistic tools to explore the temporal and spatial variations of the aquatic microbial community and can be used as sensitive indicators of the health and function of agriculturally dominated water courses. This approach also reduces computational complexity in relation to analyzing the entire microbial community for such purposes.
Assuntos
Agricultura , Rios , RNA Ribossômico 16S/genética , Água Doce , ÁguaRESUMO
BACKGROUND: Emerging pathogenic bacteria are an increasing threat to public health. Two recently described species of the genus Aliarcobacter, A. faecis and A. lanthieri, isolated from human or livestock feces, are closely related to Aliarcobacter zoonotic pathogens (A. cryaerophilus, A. skirrowii, and A. butzleri). In this study, comparative genomics analysis was carried out to examine the virulence-related, including virulence, antibiotic, and toxin (VAT) factors in the reference strains of A. faecis and A. lanthieri that may enable them to become potentially opportunistic zoonotic pathogens. RESULTS: Our results showed that the genomes of the reference strains of both species have flagella genes (flaA, flaB, flgG, flhA, flhB, fliI, fliP, motA and cheY1) as motility and export apparatus, as well as genes encoding the Twin-arginine translocation (Tat) (tatA, tatB and tatC), type II (pulE and pulF) and III (fliF, fliN and ylqH) secretory pathways, allowing them to secrete proteins into the periplasm and host cells. Invasion and immune evasion genes (ciaB, iamA, mviN, pldA, irgA and fur2) are found in both species, while adherence genes (cadF and cj1349) are only found in A. lanthieri. Acid (clpB), heat (clpA and clpB), osmotic (mviN), and low-iron (irgA and fur2) stress resistance genes were observed in both species, although urease genes were not found in them. In addition, arcB, gyrA and gyrB were found in both species, mutations of which may mediate the resistance to quaternary ammonium compounds (QACs). Furthermore, 11 VAT genes including six virulence (cadF, ciaB, irgA, mviN, pldA, and tlyA), two antibiotic resistance [tet(O) and tet(W)] and three cytolethal distending toxin (cdtA, cdtB, and cdtC) genes were validated with the PCR assays. A. lanthieri tested positive for all 11 VAT genes. By contrast, A. faecis showed positive for ten genes except for cdtB because no PCR assay for this gene was available for this species. CONCLUSIONS: The identification of the virulence, antibiotic-resistance, and toxin genes in the genomes of A. faecis and A. lanthieri reference strains through comparative genomics analysis and PCR assays highlighted the potential zoonotic pathogenicity of these two species. However, it is necessary to extend this study to include more clinical and environmental strains to explore inter-species and strain-level genetic variations in virulence-related genes and assess their potential to be opportunistic pathogens for animals and humans.
Assuntos
Antibacterianos , Fatores de Virulência , Animais , Arcobacter , Campylobacteraceae , Genômica , Virulência/genética , Fatores de Virulência/genética , Fatores de Virulência/metabolismoRESUMO
BACKGROUND: Peste des Petits Ruminants (PPR) is an acute or peracute contagious transboundary viral disease that mainly affects caprine and ovine and causes significant economic impact in developing countries. After two PPR virus outbreaks in 2011 and 2014, an investigation, from August 2015 to September 2016, was carried out in Northern Iraq when an increased morbidity and mortality rates were reported in the domestic and captive wild goats. In the present study, ten domestic goat farms and seven captive wild goat herds located in seven geographical areas of Northern Iraq were clinically, pathologically, serologically and genotypically characterized to determine the prevalence and potential cause of PPR virus outbreak. RESULTS: The outbreak occurred with rate of morbidity (26.1%) and mortality (11.1%) in domestic goat farms as compared to captive wild goat herds where relatively high mortality (42.9%) and low morbidity (10.9%) rates were recorded. Based on the clinical symptoms (mucopurulent nasal discharges, ulceration and erosion of oral mucosa, profuse watery diarrhea) and necropsy (hemorrhage and congestion on mucous membranes of the colon and rectum with zebra stripes lesions) results, overall, the serological test findings revealed a high frequency (47.9%) of positive samples for anti-PPRV nucleoprotein antibodies. Furthermore, the nucleoprotein (N) gene was detected in 63.2 and 89.1% of samples using conventional and reverse transcription real-time quantitative PCR assays. A phylogenetic analysis of N gene amino acid sequences clustered with the reference strain revealed lineage IV similar to the strains isolated in 2011 and 2014, respectively. However, two sub-types of lineage IV (I and II), significantly distinct from the previous strains, were also observed. CONCLUSION: The phylogenetic analysis suggests that movements of goats are possible cause and one of the important factors responsible for the spread of virus across the region. The study results would help in improving farm management practices by establishing a PPR virus eradication program using regular monitoring and vaccination program to control and mitigate the risk of re-emergence of PPR virus infection in domestic and captive wild goats in Iraq.
Assuntos
Doenças das Cabras/virologia , Peste dos Pequenos Ruminantes/virologia , Vírus da Peste dos Pequenos Ruminantes/isolamento & purificação , Animais , Animais Domésticos , Animais de Zoológico , Anticorpos Antivirais/sangue , Genótipo , Doenças das Cabras/epidemiologia , Doenças das Cabras/patologia , Cabras , Iraque/epidemiologia , Proteínas do Nucleocapsídeo/genética , Proteínas do Nucleocapsídeo/imunologia , Peste dos Pequenos Ruminantes/epidemiologia , Peste dos Pequenos Ruminantes/patologia , Vírus da Peste dos Pequenos Ruminantes/classificação , Vírus da Peste dos Pequenos Ruminantes/genética , Vírus da Peste dos Pequenos Ruminantes/imunologia , Fenótipo , FilogeniaRESUMO
BACKGROUND: Lumpy skin disease (LSD) is a contagious viral disease of cattle caused by lumpy skin disease virus (LSDV). LSD has recently spread in Asia following outbreaks in the Middle East and Europe. The disease emerged in Bangladesh in July 2019 in the Chattogram district, then rapidly spread throughout the entire country. We investigated six LSD outbreaks in Bangladesh to record the clinical signs and collect samples for diagnostic confirmation. Furthermore, we performed the molecular characterization of Bangladesh isolates, analyzing the full RPO30 and GPCR genes and the partial EEV glycoprotein gene. RESULTS: Clinical observations revealed common LSD clinical signs in the affected cattle. PCR and real-time PCR, showed the presence of the LSDV genome in samples from all six districts. Phylogenetic analysis and detailed inspection of multiple sequence alignments revealed that Bangladesh isolates differ from common LSDV field isolates encountered in Africa, the Middle East, and Europe, as well as newly emerged LSDV variants in Russia and China. Instead, they were closely related to LSDV KSGP-0240, LSDV NI2490, and LSDV Kenya. CONCLUSIONS: These results show the importance of continuous monitoring and characterization of circulating strains and the need to continually refine the strategies for differentiating vaccine strains from field viruses.
Assuntos
Doença Nodular Cutânea/epidemiologia , Vírus da Doença Nodular Cutânea/genética , Vírus da Doença Nodular Cutânea/isolamento & purificação , Animais , Bangladesh/epidemiologia , Bovinos , Surtos de Doenças/veterinária , Genoma Viral , Doença Nodular Cutânea/diagnóstico , Vírus da Doença Nodular Cutânea/classificação , Filogenia , Reação em Cadeia da Polimerase/veterináriaRESUMO
Rapid and accurate identification of Arcobacter is of great importance because it is considered an emerging food- and waterborne pathogen and potential zoonotic agent. Raman spectroscopy can differentiate bacteria based on Raman scattering spectral patterns of whole cells in a fast, reagentless, and easy-to-use manner. We aimed to detect and discriminate Arcobacter bacteria at the species level using confocal micro-Raman spectroscopy (785 nm) coupled with neural networks. A total of 82 reference and field isolates of 18 Arcobacter species from clinical, environmental, and agri-food sources were included. We determined that the bacterial cultivation time and growth temperature did not significantly influence the Raman spectral reproducibility and discrimination capability. The genus Arcobacter could be successfully differentiated from the closely related genera Campylobacter and Helicobacter using principal-component analysis. For the identification of Arcobacter to the species level, an accuracy of 97.2% was achieved for all 18 Arcobacter species using Raman spectroscopy combined with a convolutional neural network (CNN). The predictive capability of Raman-CNN was further validated using an independent data set of 12 Arcobacter strains. Furthermore, a Raman spectroscopy-based fully connected artificial neural network (ANN) was constructed to determine the actual ratio of a specific Arcobacter species in a bacterial mixture ranging from 5% to 100% by biomass (regression coefficient >0.99). The application of both CNN and fully connected ANN improved the accuracy of Raman spectroscopy for bacterial species determination compared to the conventional chemometrics. This newly developed approach enables rapid identification and species determination of Arcobacter within an hour following cultivation.IMPORTANCE Rapid identification of bacterial pathogens is critical for developing an early warning system and performing epidemiological investigation. Arcobacter is an emerging foodborne pathogen and has become more important in recent decades. The incidence of Arcobacter species in the agro-ecosystem is probably underestimated mainly due to the limitation in the available detection and characterization techniques. Raman spectroscopy combined with machine learning can accurately identify Arcobacter at the species level in a rapid and reliable manner, providing a promising tool for epidemiological surveillance of this microbe in the agri-food chain. The knowledge elicited from this study has the potential to be used for routine bacterial screening and diagnostics by the government, food industry, and clinics.
Assuntos
Arcobacter/classificação , Arcobacter/isolamento & purificação , Técnicas Bacteriológicas/métodos , Redes Neurais de Computação , Análise Espectral Raman/métodosRESUMO
BACKGROUND: Aliarcobacter faecis and Aliarcobacter lanthieri are recently identified as emerging human and animal pathogens. In this paper, we demonstrate the development and optimization of two direct DNA-based quantitative real-time PCR assays using species-specific oligonucleotide primer pairs derived from rpoB and gyrA genes for A. faecis and A. lanthieri, respectively. Initially, the specificity of primers and amplicon size of each target reference strain was verified and confirmed by melt curve analysis. Standard curves were developed with a minimum quantification limit of 100 cells mL- 1 or g- 1 obtained using known quantities of spiked A. faecis and A. lanthieri reference strains in autoclaved agricultural surface water and dairy cow manure samples. RESULTS: Each species-specific qPCR assay was validated and applied to determine the rate of prevalence and quantify the total number of cells of each target species in natural surface waters of an agriculturally-dominant and non-agricultural reference watershed. In addition, the prevalence and densities were determined for human and various animal (e.g., dogs, cats, dairy cow, and poultry) fecal samples. Overall, the prevalence of A. faecis for surface water and feces was 21 and 28%, respectively. The maximum A. faecis concentration for water and feces was 2.3 × 107 cells 100 mL- 1 and 1.2 × 107 cells g- 1, respectively. A. lanthieri was detected at a lower frequency (2%) with a maximum concentration in surface water of 4.2 × 105 cells 100 mL- 1; fecal samples had a prevalence and maximum density of 10% and 2.0 × 106 cells g- 1, respectively. CONCLUSIONS: The results indicate that the occurrence of these species in agricultural surface water is potentially due to fecal contamination of water from livestock, human, or wildlife as both species were detected in fecal samples. The new real-time qPCR assays can facilitate rapid and accurate detection in < 3 h to quantify total numbers of A. faecis and A. lanthieri cells present in various complex environmental samples.
Assuntos
Campylobacteraceae/isolamento & purificação , DNA Girase/genética , RNA Polimerases Dirigidas por DNA/genética , Esterco/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Microbiologia da Água , Agricultura , Animais , Proteínas de Bactérias , Campylobacteraceae/classificação , Campylobacteraceae/genética , Bovinos , Primers do DNA/genética , Humanos , Gado/microbiologia , Prevalência , Especificidade da EspécieRESUMO
The arginine vasotocin (AVT)-V1a receptor mediates critical reproductive behaviors of the nonapeptide vasotocin in the teleost brain. In this study, we report the molecular characterization of the AVT-V1a2 receptor and its messenger RNA (mRNA) and protein expressions in the Atlantic croaker brain after exposure to the planar polychlorinated biphenyl congener 3,3',4,4'-tetrachlorobiphenyl (PCB77). The full-length sequence of croaker AVT-V1a2 receptor complementary DNA (cDNA) is highly homologous to other teleost AVT-V1a2 receptor cDNAs. Double-labeled immunohistochemistry showed coexpression of AVT-V1a2 receptor and gonadotropin-releasing hormone-I (GnRH-I, a neuropeptide that regulates gonadotropin secretion) in hypothalamic neurons, thereby providing the anatomical basis for possible AVT modulation of croaker reproduction through alterations in GnRH-I secretion. AVT-V1a2 receptor mRNA and protein levels as well as GnRH-I mRNA levels were markedly decreased in hypothalamic tissues of croaker exposed to PCB77 (dose: 2 and 8 µg/g body weight for 4 weeks) compared with levels in untreated (control) fish. In contrast, hypothalamic cytochrome P450 1A (CYP1A, a monooxygenase enzyme) and interleukin-1ß (IL-1ß, a cytokine indicator of inflammation and response to neuronal damage) mRNA levels, and plasma protein carbonyl (PC, an indicator of reactive oxygen species) contents, important biomarkers of neural stress, were increased in PCB77-exposed fish compared with controls. Collectively, these results suggest that the downregulation of hypothalamic AVT-V1a2 receptor and GnRH-I transcripts due to PCB77 exposure is associated with induction of CYP1A, cellular inflammation and oxidative stress in Atlantic croaker, a marine teleost that inhabits estuaries along the US Atlantic coast and the Gulf of Mexico that are often contaminated with persistent organic pollutants such as PCBs.
Assuntos
Encéfalo/metabolismo , Regulação para Baixo/efeitos dos fármacos , Perciformes/metabolismo , Bifenilos Policlorados/farmacologia , Receptores de Vasopressinas/genética , Receptores de Vasopressinas/metabolismo , Poluentes Químicos da Água/farmacologia , Animais , Sequência de Bases , Encéfalo/efeitos dos fármacos , Citocromo P-450 CYP1A1/genética , DNA Complementar/genética , Feminino , Expressão Gênica/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/metabolismo , Hipotálamo/citologia , Masculino , Neurônios/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Filogenia , Precursores de Proteínas/metabolismo , RNA Mensageiro/genética , Reprodução/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacosRESUMO
BACKGROUND: Arcobacter faecis and A. lanthieri are two newly classified species of genus Arcobacter. The prevalence and distribution of virulence, antibiotic resistance and toxin (VAT) genes in these species are required to assess their potential pathogenic health impacts to humans and animals. This study (i) developed species- and gene-specific primer pairs for the detection of six virulence, two antibiotic resistance, and three toxin genes in two target species; (ii) optimized eight single-tube multiplex and three monoplex PCR protocols using the newly developed species- and gene-specific primers; and (iii) conducted specificity and sensitivity evaluations as well as validation of eleven mono- and multiplex PCR assays by testing A. faecis (n= 29) and A. lanthieri (n= 10) strains isolated from various fecal and agricultural water sources to determine the prevalence and distribution of VAT genes and assess the degree of pathogenicity within the two species. RESULTS: Detection of all ten and eleven target VAT genes, and expression of cytolethal distending toxin (cdtA, cdtB and cdtC) genes in A. faecis and A. lanthieri reference strains with high frequency in field isolates suggest that they are potentially pathogenic strains. These findings indicate that these two species can pose a health risk to humans and animals. CONCLUSIONS: The study results show that the developed mono- and multiplex PCR (mPCR) assays are simple, rapid, reliable and sensitive for the simultaneous assessment of the potential pathogenicity and antibiotic resistance profiling of tet(O) and tet(W) genes in these two newly discovered species. Also, these assays can be useful in diagnostic and analytical laboratories to determine the pathotypes and assessment of the virulence and toxin factors associated to human and animal infections.
Assuntos
Arcobacter , Toxinas Bacterianas/genética , Técnicas de Tipagem Bacteriana/métodos , Resistência Microbiana a Medicamentos/genética , Infecções por Bactérias Gram-Negativas/microbiologia , Reação em Cadeia da Polimerase , Virulência/genética , Animais , Arcobacter/efeitos dos fármacos , Arcobacter/genética , Arcobacter/patogenicidade , Técnicas de Tipagem Bacteriana/normas , Genes Bacterianos/genética , Infecções por Bactérias Gram-Negativas/diagnóstico , Humanos , Reação em Cadeia da Polimerase Multiplex/normas , Reação em Cadeia da Polimerase/normas , Sensibilidade e EspecificidadeRESUMO
BACKGROUND: Dialysis withdrawal is the third most common cause of death in patients receiving dialysis for established renal failure (ERF) in Scotland. We describe incidence, risk factors and themes influencing decision-making in a national renal registry. METHODS: Details of deaths in those receiving renal replacement therapy (RRT) for ERF in Scotland are reported to the Scottish Renal Registry via a unique mortality report. We extracted patient demographics and comorbidity, cause and location of death, duration of RRT and pertinent free text comments from 1 January 2008 to 31 December 2014. Withdrawal incidence was calculated and logistic regression used to identify significantly influential variables. Themes emerging from clinician comments were tabulated for descriptive purposes. RESULTS: There were 2596 deaths; median age at death was 68 [interquartile range (IQR) 58, 76] years, 41.5% were female. Median duration on RRT was 1110 (IQR 417, 2151) days. Dialysis withdrawal was the primary cause of death in 497 (19.1%) patients and withdrawal contributed to death in a further 442 cases (17.0%). The incidence was 41 episodes per 1000 patient-years. Regression analysis revealed increasing age, female sex and prior cerebrovascular disease were associated with dialysis withdrawal as a primary cause of death. Conversely, interstitial renal disease, angiographically proven ischaemic heart disease, valvular heart disease and malignancy were negatively associated. Analysis of free text comments revealed common themes, portraying an image of physical and psychological decline accelerated by acute illnesses. CONCLUSIONS: Death following dialysis withdrawal is common. Factors important to physical independence-prior cerebrovascular disease and increasing age-are associated with withdrawal. When combined with clinician comments this study provides an insight into the clinical decline affecting patients and the complexity of this decision. Early recognition of those likely to withdraw may improve end of life care.
Assuntos
Falência Renal Crônica/terapia , Sistema de Registros/estatística & dados numéricos , Diálise Renal/mortalidade , Suspensão de Tratamento/estatística & dados numéricos , Idoso , Feminino , Humanos , Masculino , Taxa de SobrevidaRESUMO
The arginine vasotocin/vasopressin (AVT/AVP) and gonadotropin releasing hormone (GnRH) systems are known to control sexual behaviors and reproduction, respectively, in different vertebrate groups. However, a direct functional connection between these two neuroendocrine systems has not been demonstrated for any vertebrate species. Therefore, the objective of this research was to test the hypothesis that AVT acts on the GnRH system via an AVT V1a receptor in a sex changing grouper species, the rock hind, Epinephelus adscensionis. AVT V1a2 receptors were co-localized with GnRH-I on neurons in the preoptic anterior hypothalamus identifying a structural linkage between the AVT system and GnRH-I. Transcripts for avt, gnrh-I, and two AVT receptor subtypes (v1a1 and v1a2) were isolated and characterized for E. adscensionis and their expression was measured in males and females by q-RT-PCR. Translation of V1a-type cDNA sequences revealed two distinct forms of the AVT V1a receptor in E. adscensionis brain similar to those reported for other species. The observation of significantly higher gnrh-I mRNA in the POA+H of rock hind males as compared to females suggests differential regulation of the gnrh-I transcripts in the two sexes of this protogynous species. In male E. adscensionis, but not in females, a negative relationship was seen between plasma 11-ketotestosterone (11-KT) and the v1a1 receptor mRNA levels in the POA+H, while a positive trend was observed between 11-KT and v1a2 receptor mRNA levels, indicating that these receptor forms may be differentially regulated.
Assuntos
Bass/metabolismo , Hormônio Liberador de Gonadotropina/metabolismo , Neurônios/metabolismo , Área Pré-Óptica/metabolismo , Precursores de Proteínas/metabolismo , Receptores de Vasopressinas/metabolismo , Animais , Arginina Vasopressina/metabolismo , Bass/genética , Feminino , Hormônio Liberador de Gonadotropina/genética , Masculino , Precursores de Proteínas/genética , RNA Mensageiro/genética , Receptores de Vasopressinas/genética , Reprodução/genética , Processos de Determinação Sexual/genética , Testosterona/análogos & derivados , Vasotocina/metabolismoRESUMO
A study was undertaken to determine the prevalence and diversity of species of the genus Arcobacter in pig and dairy cattle manure, which led to the identification of strains AF1440T, AF1430 and AF1581. Initially identified as Arcobacter butzleri based on colony morphology and initial PCR-confirmation tests, analyses of 16S rRNA gene sequences of these strains confirmed that they belonged to the genus Arcobacter and were different from all known species of the genus. The isolates formed a distinct group within the genus Arcobacter based on their 16S rRNA, gyrB, rpoB, cpn60, gyrA and atpA gene sequences and fatty acid profiles. Their unique species status was further supported by physiological properties and DNA-DNA hybridization that allowed phenotypic and genotypic differentiation of the strains from other species of the genus Arcobacter. The isolates were found to be oxidase, catalase and esterase positive and urease negative; they grew well at 30 °C under microaerophilic conditions and produced nitrite and acetoin. Based on their common origin and various physiological properties, it is proposed that the isolates are classified as members of a novel species with the name Arcobacter lanthieri sp. nov. The type strain is AF1440T ( = LMG 28516T = CCUG 66485T); strains AF1430 ( = LMG 28515 = CCUG 66486) and AF1581 ( = LMG 28517 = CCUG 66487) are reference strains.
Assuntos
Arcobacter/classificação , Esterco/microbiologia , Filogenia , Animais , Arcobacter/genética , Arcobacter/isolamento & purificação , Composição de Bases , Bovinos , DNA Bacteriano/genética , Ácidos Graxos/química , Genes Bacterianos , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Ontário , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , SuínosRESUMO
Surface waters from paired agricultural watersheds under controlled tile drainage (CTD) and uncontrolled tile drainage (UCTD) were monitored over 7 years in order to determine if there was an effect of CTD (imposed during the growing season) on occurrences and loadings of bacterial and viral pathogens, coliphages, and microbial source tracking markers. There were significantly lower occurrences of human, ruminant, and livestock (ruminant plus pig) Bacteroidales markers in the CTD watershed in relation to the UCTD watershed. As for pathogens, there were significantly lower occurrences of Salmonella spp. and Arcobacter spp. in the CTD watershed. There were no instances where there were significantly higher quantitative loadings of any microbial target in the CTD watershed, except for F-specific DNA (F-DNA) and F-RNA coliphages, perhaps as a result of fecal inputs from a hobby farm independent of the drainage practice treatments. There was lower loading of the ruminant marker in the CTD watershed in relation to the UCTD system, and results were significant at the level P = 0.06. The odds of Salmonella spp. occurring increased when a ruminant marker was present relative to when the ruminant marker was absent, yet for Arcobacter spp., the odds of this pathogen occurring significantly decreased when a ruminant marker was present relative to when the ruminant marker was absent (but increased when a wildlife marker was present relative to when the wildlife marker was absent). Interestingly, the odds of norovirus GII (associated with human and swine) occurring in water increased significantly when a ruminant marker was present relative to when a ruminant marker was absent. Overall, this study suggests that fecal pollution from tile-drained fields to stream could be reduced by CTD utilization.
Assuntos
Bactérias/isolamento & purificação , Biomarcadores/química , Monitoramento Ambiental , Rios/microbiologia , Rios/virologia , Vírus/isolamento & purificação , Agricultura , Animais , Bactérias/genética , Humanos , Rios/química , Estações do Ano , Vírus/genética , Microbiologia da ÁguaRESUMO
BACKGROUND: Patients receiving treatment with renal replacement therapy (RRT) have high mortality, and ensuring patient safety in this population is difficult. We aimed to estimate the incidence and nature of medical adverse events contributing to the death of patients being treated with RRT. METHODS: This population registry-based retrospective case review study included all patients being treated with RRT for established renal failure in Scotland and who died between 1 January 2008 and 30 June 2011. Deaths were reviewed by consultant nephrologists using a structured questionnaire to identify factors contributing to death occurring in both the inpatient and outpatient setting. Reviewers were able to use any information source deemed relevant, including paper and electronic clinical records, mortality and morbidity meetings and procurator fiscal (Scottish coroner) investigations. Deaths occurring in 2008 and 2009 where avoidable factors were identified that may have or did lead to death of a patient were subject to further review and root cause analysis, in order to identify recurrent themes. RESULTS: Of 1551 deaths in the study period, 1357 were reviewed (87.5%). Cumulative RRT exposure in the cohort was 2.78 million person-days. RRT complications were the primary cause of death in 28 (2.1%). Health-care-associated infection had contributed to 9.6% of all deaths. In 3.5% of deaths, factors were identified which may have or did contribute to death. These were both organizational and human error related and were largely due to five main causes: management of hyperkalaemia, prescribing, out of hours care, infection and haemodialysis vascular access. CONCLUSIONS: Adverse events contributing to death in RRT recipients mainly relate to the everyday management of common medical problems and not the technical aspects of RRT. Efforts to avoid harm in this population should address these ubiquitous causes of harm.
Assuntos
Falência Renal Crônica/mortalidade , Terapia de Substituição Renal/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Incidência , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Diálise Renal , Estudos Retrospectivos , Fatores de Risco , Taxa de SobrevidaRESUMO
BACKGROUND: Peritonitis is the most frequent serious complication of continuous ambulatory peritoneal dialysis (CAPD). It has a major influence on the number of patients switching from CAPD to haemodialysis and has probably restricted the wider acceptance and uptake of CAPD as an alternative mode of dialysis.This is an update of a review first published in 2000. OBJECTIVES: This systematic review sought to determine if modifications of the transfer set (Y-set or double bag systems) used in CAPD exchanges are associated with a reduction in peritonitis and an improvement in other relevant outcomes. SEARCH METHODS: We searched the Cochrane Renal Group's Specialised Register through contact with the Trials Search Co-ordinator. Studies contained in the Specialised Register are identified through search strategies specifically designed for CENTRAL, MEDLINE and EMBASE. Date of last search: 22 October 2013. SELECTION CRITERIA: Randomised controlled trials (RCTs) or quasi-RCTs comparing double bag, Y-set and standard peritoneal dialysis (PD) exchange systems in patients with end-stage kidney disease. DATA COLLECTION AND ANALYSIS: Data were abstracted by a single investigator onto a standard form and analysed by Review Manager. Analysis was by a random effects model and results were expressed as risk ratio (RR) or mean difference (MD) with 95% confidence intervals (CI). MAIN RESULTS: Twelve eligible trials with a total of 991 randomised patients were identified. Despite the large total number of patients, few trials covered the same interventions, small numbers of patients were enrolled in each trial and the methodological quality was suboptimal. Y-set and twin-bag systems were superior to conventional spike systems (7 trials, 485 patients, RR 0.64, 95% CI 0.53 to 0.77) in preventing peritonitis in PD. AUTHORS' CONCLUSIONS: Disconnect systems should be the preferred exchange systems in CAPD.
Assuntos
Falência Renal Crônica/terapia , Diálise Peritoneal Ambulatorial Contínua/instrumentação , Peritonite/prevenção & controle , Desenho de Equipamento , Humanos , Diálise Peritoneal Ambulatorial Contínua/efeitos adversos , Diálise Peritoneal Ambulatorial Contínua/métodos , Peritonite/etiologia , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
The excessive and uncontrolled application of antibiotics in the fish farming industry, coupled with a lack of health monitoring and medication practices, is a driving force behind the escalating development of antimicrobial resistance. The present study assessed and compared qualitative field diffusion (QFD) and disk diffusion (DD) assays for the detection of antimicrobial residues (ARs) in diverse freshwater aquaculture fish. A total of 380 freshwater aquaculture fish (160 fresh and 180 frozen) samples were systematically collected between January and June 2021 from various retail stores located in Erbil Governorate, Iraq. Based on QFDA results, overall, ARs were detected (52; 15.3%) at a relatively lower frequency with comparatively higher frequency (21; 31.1%) in fresh than (31; 17.2%) frozen fish samples. On the other hand, DDA also revealed a comparable (45; 13.2%) prevalence rate of ARs. However, a low detection was observed more in fresh (17; 10.6%) than frozen (28; 15.6%) fish samples. Moreover, no statistically significant disparity (χ2 = 0.069; p = 0.79) between two assays and types of fish was recorded. In conclusion, the results of the present study showed that detecting a considerable frequency of ARs in these fish samples raises concerns about potential threats to public health. This underscores the necessity for understanding antibiotic application in aquaculture and its potential connection to antibiotic resistance in bacterial pathogens. Such comprehension is pivotal for formulating and implementing effective control and farm management strategies to address this pressing issue.
RESUMO
Leakage and tampering problems in collection and transmission of biomedical data have attracted much attention as these concerns instigates negative impression regarding privacy, security, and reputation of medical networks. This article presents a novel security model that establishes a threat-vector database based on the dynamic behaviours of smart healthcare systems. Then, an improved and privacy-preserved SRU network is designed that aims to alleviate fading gradient issue and enhance the learning process by reducing computational cost. Then, an intelligent federated learning algorithm is deployed to enable multiple healthcare networks to form a collaborative security model in a personalized manner without the loss of privacy. The proposed security method is both parallelizable and computationally effective since the dynamic behaviour aggregation strategy empowers the model to work collaboratively and reduce communication overhead by dynamically adjusting the number of participating clients. Additionally, the visualization of the decision process based on the explainability of features enhances the understanding of security experts by enabling them to comprehend the underlying data evidence and causal reasoning. Compared to existing methods, the proposed security method is capable of thoroughly analyzing and detecting severe security threats with high accuracy, reduce overhead and lower computation cost along with enhanced privacy of biomedical data.