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OBJECTIVE: The first objective of the study aimed to detect the presence of Lactococcus petauri, L. garvieae, and L. formosensis in fish (n = 359) and environmental (n = 161) samples from four lakes near an affected fish farm in California during an outbreak in 2020. The second objective was to compare the virulence of the Lactococcus spp. in Rainbow Trout Oncorhynchus mykiss and Largemouth Bass Micropterus salmoides. METHODS: Standard bacterial culture methods were used to isolate Lactococcus spp. from brain and posterior kidney of sampled fish from the four lakes. Quantitative PCR (qPCR) was utilized to detect Lactococcus spp. DNA in fish tissues and environmental samples from the four lakes. Laboratory controlled challenges were conducted by injecting fish intracoelomically with representative isolates of L. petauri (n = 17), L. garvieae (n = 2), or L. formosensis (n = 4), and monitored for 14 days postchallenge (dpc). RESULT: Lactococcus garvieae was isolated from the brains of two Largemouth Bass in one of the lakes. Lactococcus spp. were detected in 14 fish (8 Bluegills Lepomis macrochirus and 6 Largemouth Bass) from 3 out of the 4 lakes using a qPCR assay. Of the collected environmental samples, all 4 lakes tested positive for Lactococcus spp. in the soil samples, while 2 of the 4 lakes tested positive in the water samples through qPCR. Challenged Largemouth Bass did not show any signs of infection postinjection throughout the challenge period. Rainbow Trout infected with L. petauri showed clinical signs within 3 dpc and presented a significantly higher cumulative mortality (62.4%; p < 0.0001) at 14 dpc when compared to L. garvieae (0%) and L. formosensis (7.5%) treatments. CONCLUSION: The study suggests that qPCR can be used for environmental DNA monitoring of Lactococcus spp. and demonstrates virulence diversity between the etiological agents of piscine lactococcosis.
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Enfermedades de los Peces , Infecciones por Bacterias Grampositivas , Oncorhynchus mykiss , Animales , Virulencia , Infecciones por Bacterias Grampositivas/epidemiología , Infecciones por Bacterias Grampositivas/veterinaria , Infecciones por Bacterias Grampositivas/microbiología , Lagos , Lactococcus/genética , Enfermedades de los Peces/epidemiología , Enfermedades de los Peces/microbiologíaRESUMEN
OBJECTIVES: The diagnosis of osteoid osteomas (OO) about the hip can be challenging as presenting symptoms can mimic other, more common, periarticular pathologies. Our aims were to identify the most common misdiagnoses and treatments, mean delay in diagnosis, characteristic imaging features and provide tips for avoiding diagnostic imaging pitfalls for patients with OO of the hip. METHODS: We identified 33 patients (34 tumors) with OO about the hip who were referred for radiofrequency ablation between 1998 and 2020. Imaging studies reviewed included radiographs (n = 29), CT (n = 34), and MRI (n = 26). RESULTS: The most common initial diagnoses were femoral neck stress fracture (n = 8), femoroacetabular impingement (FAI) (n = 7), and malignant tumor or infection (n = 4). The mean time from symptom onset to diagnosis of OO was 15 months (range, 0.4-84). The mean time from initial incorrect diagnosis to OO diagnosis was 9 months (range, 0-46). CONCLUSIONS: The diagnosis of OO of the hip is challenging, with up to 70% of cases initially misdiagnosed as a femoral neck stress fracture, FAI, bone tumor, or other joint pathology in our series. Consideration of OO in the differential diagnosis of hip pain in adolescent patients and awareness of the characteristic imaging findings are critical for making an accurate diagnosis. KEY POINTS: ⢠The diagnosis of osteoid osteoma of the hip can be challenging, as demonstrated by long delays in time to initial diagnosis and high rates of misdiagnoses which can lead to inappropriate interventions. ⢠Familiarity with the spectrum of imaging features of OO, especially on MRI, is imperative given the increase in the utilization of this modality for the evaluation of young patients with hip pain and FAI. ⢠Consideration of OO in the differential diagnosis of hip pain in adolescent patients and awareness of the characteristic imaging findings, including bone marrow edema and the utility of CT, are critical for making a timely and accurate diagnosis.
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Neoplasias Óseas , Pinzamiento Femoroacetabular , Fracturas del Cuello Femoral , Fracturas por Estrés , Osteoma Osteoide , Adolescente , Humanos , Osteoma Osteoide/cirugía , Neoplasias Óseas/diagnóstico , Errores Diagnósticos , ArtralgiaRESUMEN
Lactococcus petauri is an important emergent bacterial pathogen of salmonids in the USA. The purpose of this study was to evaluate the protection conferred to rainbow trout (Oncorhynchus mykiss) against L. petauri by formalin-killed vaccines in immersion and injectable forms, as well as the enhanced protection afforded by booster vaccination. In the first challenge, fish were immunized via intracoelomic injection (IC) or immersion (Imm) routes alone. Approximately 418 degree days (Temperature in degree Celsius × days post-immunization) (dd) Imm, or 622 dd IC post-vaccination, fish were challenged via IC with wild-type L. petauri. In the second experiment, initial Imm vaccination was followed by booster vaccination via Imm or IC routes 273 dd post-immunization along with appropriate PBS controls. The various vaccination protocol efficacies were evaluated by challenging fish with L. petauri by cohabitation with diseased fish 399 dd post-booster administration. A relative percent survival (RPS) of 89.5% and 28% was recorded in the IC and Imm single immunization treatments, respectively. In the second study, an RPS of 97.5%, 10.2%, 2.6% and -10.1% plus approximately 0%, 50%, 20%, and 30% bacterial persistence was recorded in the Imm immunized + IC boosted, Imm immunized + mock IC boosted, Imm immunized + Imm boosted, and Imm immunized + mock Imm boosted treatments, respectively. Only the Imm immunized + IC injection boosted treatments provided significant protection when compared to unvaccinated and challenged treatments (p < 0.05). In conclusion, although both Imm and IC vaccines appear safe for trout, the inactivated Imm vaccines seem to provide only mild and temporary protection against lactococcosis; whereas IC immunized trout develop a significantly stronger protective response in both challenges.
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While both virulent and putatively avirulent Yersinia ruckeri strains exist in aquaculture environments, the relationship between the distribution of virulence-associated factors and de facto pathogenicity in fish remains poorly understood. Pan-genome analysis of 18 complete genomes, representing established virulent and putatively avirulent lineages of Y. ruckeri, revealed the presence of a number of accessory genetic determinants. Further investigation of 68 draft genome assemblies revealed that the distribution of certain putative virulence factors correlated well with virulence and host-specificity. The inverse-autotransporter invasin locus yrIlm was, however, the only gene present in all virulent strains, while absent in lineages regarded as avirulent. Strains known to be associated with significant mortalities in salmonid aquaculture display a combination of serotype O1-LPS and yrIlm, with the well-documented highly virulent lineages, represented by MLVA clonal complexes 1 and 2, displaying duplication of the yrIlm locus. Duplication of the yrIlm locus was further found to have evolved over time in clonal complex 1, where some modern, highly virulent isolates display up to three copies.
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Enfermedades de los Peces , Oncorhynchus mykiss , Yersiniosis , Animales , Yersinia ruckeri/genética , Virulencia/genética , SerogrupoRESUMEN
BACKGROUND: The benefits of standardized care for cardiogenic shock (CS) across regional care networks are poorly understood. OBJECTIVES: The authors compared the management and outcomes of CS patients initially presenting to hub versus spoke hospitals within a regional care network. METHODS: The authors stratified consecutive patients enrolled in their CS registry (January 2017 to December 2019) by presentation to a spoke versus the hub hospital. The primary endpoint was 30-day mortality. Secondary endpoints included bleeding, stroke, or major adverse cardiovascular and cerebrovascular events. RESULTS: Of 520 CS patients, 286 (55%) initially presented to 34 spoke hospitals. No difference in mean age (62 years vs 61 years; P = 0.38), sex (25% vs 32% women; P = 0.10), and race (54% vs 52% white; P = 0.82) between spoke and hub patients was noted. Spoke patients more often presented with acute myocardial infarction (50% vs 32%; P < 0.01), received vasopressors (74% vs 66%; P = 0.04), and intra-aortic balloon pumps (88% vs 37%; P < 0.01). Hub patients were more often supported with percutaneous ventricular assist devices (44% vs 11%; P < 0.01) and veno-arterial extracorporeal membrane oxygenation (13% vs 0%; P < 0.01). Initial presentation to a spoke was not associated with increased risk-adjusted 30-day mortality (adjusted OR: 0.87 [95% CI: 0.49-1.55]; P = 0.64), bleeding (adjusted OR: 0.89 [95% CI: 0.49-1.62]; P = 0.70), stroke (adjusted OR: 0.74 [95% CI: 0.31-1.75]; P = 0.49), or major adverse cardiovascular and cerebrovascular events (adjusted OR 0.83 [95% CI: 0.50-1.35]; P = 0.44). CONCLUSIONS: Spoke and hub patients experienced similar short-term outcomes within a regionalized CS network. The optimal strategy to promote standardized care and improved outcomes across regional CS networks merits further investigation.
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Insuficiencia Cardíaca , Corazón Auxiliar , Infarto del Miocardio , Accidente Cerebrovascular , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/terapia , Choque Cardiogénico/terapia , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/terapiaRESUMEN
Aquaculture is an important tool for solving the growing worldwide food demand, but infectious diseases of farmed animals represent a serious roadblock to continued industry growth. Therefore, it is essential to understand the microbial communities that reside within the built environments of aquaculture facilities to identify reservoirs of bacterial pathogens and potential correlations between commensal species and specific disease agents. Here, we present the results from 3 years of sampling a commercial rainbow trout aquaculture facility. We observed that the microbial communities residing on the abiotic surfaces within the hatchery were distinct from those residing on the surfaces at the facility's water source as well as the production raceways, despite similar communities in the water column at each location. Also, a subset of the water community seeds the biofilm communities. Lastly, we detected a common fish pathogen, Flavobacterium columnare, within the hatchery, including at the source water inlet. Importantly, the relative abundance of this pathogen was correlated with clinical disease. Our results characterized the microbial communities in an aquaculture facility, established that the hatchery environment contains a unique community composition and demonstrated that a specific fish pathogen resides within abiotic surface biofilms and is seeded from the natural water source.
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Enfermedades de los Peces , Microbiota , Oncorhynchus mykiss , Animales , Acuicultura , Enfermedades de los Peces/microbiología , Flavobacterium/genética , Agua Dulce/microbiología , AguaRESUMEN
Although a number of genetically diverse Yersinia ruckeri strains are present in Norwegian aquaculture environments, most if not all outbreaks of yersiniosis in Atlantic salmon in Norway are associated with a single specific genetic lineage of serotype O1, termed clonal complex 1. To investigate the presence and spread of virulent and putatively avirulent strains in Norwegian salmon farms, PCR assays specific for Y. ruckeri (species level) and Y. ruckeri clonal complex 1 were developed. Following extensive screening of water and biofilm, the widespread prevalence of putatively avirulent Y. ruckeri strains was confirmed in freshwater salmon hatcheries, while Y. ruckeri clonal complex 1 was found in fewer farms. The formalin-killed bacterin yersiniosis vaccine was detected in environmental samples by both PCR assays for several weeks post-vaccination. It is thus important to interpret results from recently vaccinated fish with great care. Moreover, field studies and laboratory trials confirmed that stressful management procedures may result in increased shedding of Y. ruckeri by sub-clinically infected fish. Analysis of sea water sampled throughout thermal delousing procedures proved effective for detection of Y. ruckeri in sub-clinically infected populations.
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Enfermedades de los Peces , Oncorhynchus mykiss , Salmo salar , Yersiniosis , Animales , Acuicultura , Enfermedades de los Peces/epidemiología , Enfermedades de los Peces/prevención & control , Oncorhynchus mykiss/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Salmo salar/genética , Yersiniosis/epidemiología , Yersiniosis/prevención & control , Yersiniosis/veterinaria , Yersinia ruckeri/genéticaRESUMEN
This case highlights an impressive manifestation of a diagnosis that affects many people around the world.
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BACKGROUND: Little is known about clinical characteristics, hospital course, and longitudinal outcomes of patients with cardiogenic shock (CS) related to heart failure (HF-CS) compared to acute myocardial infarction (AMI; CS related to AMI [AMI-CS]). METHODS: We examined in-hospital and 1-year outcomes of 520 (219 AMI-CS, 301 HF-CS) consecutive patients with CS (January 3, 2017-December 31, 2019) in a single-center registry. RESULTS: Mean age was 61.5±13.5 years, 71% were male, 22% were Black patients, and 63% had chronic kidney disease. The HF-CS cohort was younger (58.5 versus 65.6 years, P<0.001), had fewer cardiac arrests (15.9% versus 35.2%, P<0.001), less vasopressor utilization (61.8% versus 82.2%, P<0.001), higher pulmonary artery pulsatility index (2.14 versus 1.51, P<0.01), lower cardiac power output (0.64 versus 0.77 W, P<0.01) and higher pulmonary capillary wedge pressure (25.4 versus 22.2 mm Hg, P<0.001) than patients with AMI-CS. Patients with HF-CS received less temporary mechanical circulatory support (34.9% versus 76.3% P<0.001) and experienced lower rates of major bleeding (17.3% versus 26.0%, P=0.02) and in-hospital mortality (23.9% versus 39.3%, P<0.001). Postdischarge, 133 AMI-CS and 229 patients with HF-CS experienced similar rates of 30-day readmission (19.5% versus 24.5%, P=0.30) and major adverse cardiac and cerebrovascular events (23.3% versus 28.8%, P=0.45). Patients with HF-CS had lower 1-year mortality (n=123, 42.6%) compared to the patients with AMI-CS (n=110, 52.9%, P=0.03). Cumulative 1-year mortality was also lower in patients with HF-CS (log-rank test, P=0.04). CONCLUSIONS: Patients with HF-CS were younger, and despite lower cardiac power output and higher pulmonary capillary wedge pressure, less likely to receive vasopressors or temporary mechanical circulatory support. Although patients with HF-CS had lower in-hospital and 1-year mortality, both cohorts experienced similarly high rates of postdischarge major adverse cardiovascular and cerebrovascular events and 30-day readmission, highlighting that both cohorts warrant careful long-term follow-up. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT03378739.
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Insuficiencia Cardíaca , Infarto del Miocardio , Cuidados Posteriores , Anciano , Femenino , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/terapia , Mortalidad Hospitalaria , Hospitales , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/complicaciones , Infarto del Miocardio/terapia , Alta del Paciente , Choque Cardiogénico/diagnóstico , Choque Cardiogénico/terapiaRESUMEN
BACKGROUND: Given the complex nature of liver transplant surgery, adult centers typically use a dedicated liver transplant anesthesia team, which has improved patient outcomes. AIMS: Our goal was to determine whether a dedicated pediatric liver transplant anesthesia team was associated with improved patient outcomes. METHODS: This retrospective cohort study analyzed patients who underwent liver transplantation from April 2013 to September 2020 at St. Louis Children's Hospital. The general group (April 2013-December 2016) was compared with the liver group (January 2017-September 2020). Outcomes measured included cases per anesthesiologist, early extubation, ventilator days, fluid and blood administration, postoperative events, and intensive care unit and hospital length of stay (LOS). RESULTS: Patients in both groups had similar demographics. The average number of cases/anesthesiologist/year was 2.9 times higher in the liver group (mean (SD) general 0.7 (0.5), liver 2.0 (0.6), and difference in mean [95% CI] 1.3 [0.8, 1.8]). The rate of extubation in the operating room was higher for patients in the liver group (general 56%, liver 80%, and difference in proportion [95% CI] 24.7 [7.0, 42.4]), while the number of ventilator days was lower (mean (SD) general 2.1 (4.4), liver 1.1 (3.6), and difference in proportion [95%CI] -0.9 [-2.6, 0.7]). Colloid administration was higher in the liver group (mean (SD) general 23.9 (14.5) ml/kg, liver 48.4 (37.7) ml/kg, and difference in mean [95% CI] 24.6 [12.7, 36.4]), while fresh frozen plasma administration was lower in the liver group (mean (SD) general 15.3 (23.9) ml/kg, liver 6.2 (14) ml/kg, and difference in mean [95% CI] -9.0 [-16.8, -1.3]). There were no significant differences between the groups in postoperative events including blood product transfusions, vasopressor use, and thromboses, or in the intensive care unit and hospital LOS. CONCLUSIONS: The liver group was associated with increased early extubations, decreased ventilator days, and decreased fresh frozen plasma use.
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Anestesia , Trasplante de Hígado , Adulto , Extubación Traqueal , Niño , Humanos , Tiempo de Internación , Estudios RetrospectivosRESUMEN
Flavobacterium columnare causes columnaris disease in wild and cultured freshwater fish and is a major problem for sustainable aquaculture worldwide. The F. columnare type IX secretion system (T9SS) secretes many proteins and is required for virulence. The T9SS component GldN is required for secretion and gliding motility over surfaces. Genetic manipulation of F. columnare is inefficient, which has impeded identification of secreted proteins that are critical for virulence. Here, we identified a virulent wild-type F. columnare strain (MS-FC-4) that is highly amenable to genetic manipulation. This facilitated isolation and characterization of two deletion mutants lacking core components of the T9SS. Deletion of gldN disrupted protein secretion and gliding motility and eliminated virulence in zebrafish and rainbow trout. Deletion of porV disrupted secretion and virulence but not motility. Both mutants exhibited decreased extracellular proteolytic, hemolytic, and chondroitin sulfate lyase activities. They also exhibited decreased biofilm formation and decreased attachment to fish fins and other surfaces. Using genomic and proteomic approaches, we identified proteins secreted by the T9SS. We deleted 10 genes encoding secreted proteins and characterized the virulence of mutants lacking individual or multiple secreted proteins. A mutant lacking two genes encoding predicted peptidases exhibited reduced virulence in rainbow trout, and mutants lacking a predicted cytolysin showed reduced virulence in zebrafish and rainbow trout. The results establish F. columnare strain MS-FC-4 as a genetically amenable model to identify virulence factors. This may aid development of measures to control columnaris disease and impact fish health and sustainable aquaculture. IMPORTANCE Flavobacterium columnare causes columnaris disease in wild and aquaculture-reared freshwater fish and is a major problem for aquaculture. Little is known regarding the virulence factors involved in this disease, and control measures are inadequate. The type IX secretion system (T9SS) secretes many proteins and is required for virulence, but the secreted virulence factors are not known. We identified a strain of F. columnare (MS-FC-4) that is well suited for genetic manipulation. The components of the T9SS and the proteins secreted by this system were identified. Deletion of core T9SS genes eliminated virulence. Genes encoding 10 secreted proteins were deleted. Deletion of two peptidase-encoding genes resulted in decreased virulence in rainbow trout, and deletion of a cytolysin-encoding gene resulted in decreased virulence in rainbow trout and zebrafish. Secreted peptidases and cytolysins are likely virulence factors and are targets for the development of control measures.
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Enfermedades de los Peces , Infecciones por Flavobacteriaceae , Animales , Enfermedades de los Peces/microbiología , Infecciones por Flavobacteriaceae/microbiología , Infecciones por Flavobacteriaceae/veterinaria , Flavobacterium , Proteómica , Virulencia , Pez CebraRESUMEN
Diseases caused by the fish pathogens Flavobacterium columnare and Flavobacterium psychrophilum are major contributors of preventable losses in the aquaculture industry. The persistent and difficult-to-control infections caused by these bacteria make timely intervention and prophylactic elimination of pathogen reservoirs important measures to combat these disease-causing agents. In this study, we present two independent assays for detecting these pathogens in a range of environmental samples. Natural water samples were inoculated with F. columnare and F. psychrophilum over 5 orders of magnitude, and pathogen levels were detected using Illumina MiSeq sequencing and droplet digital PCR. Both detection methods accurately identified pathogen-positive samples and showed good agreement in quantifying each pathogen. Additionally, the real-world application of these approaches was demonstrated using environmental samples collected at a rainbow trout (Oncorhynchus mykiss) aquaculture facility. These results show that both methods can serve as useful tools for surveillance efforts in aquaculture facilities, where the early detection of these flavobacterial pathogens may direct preventative measures to reduce disease occurrence. IMPORTANCE Early detection of a deadly disease outbreak in a population can be the difference between mass mortality or mitigated effects. In the present study, we evaluated and compared two molecular techniques for detecting economically impactful aquaculture pathogens. We demonstrate that one of these techniques, 16S rRNA gene sequencing using Illumina MiSeq technology, provides the ability to accurately detect two freshwater fish pathogens, F. columnare and F. psychrophilum, while simultaneously profiling the native microbial community. The second technique, droplet digital PCR, is commonly used for pathogen detection, and the results obtained using the assays we designed with this method served to validate those obtained using the MiSeq method. These two methods offer distinct advantages. The MiSeq method pairs pathogen detection and microbial community profiling to answer immediate and long-term fish health concerns, while the droplet digital PCR method provides fast and highly sensitive detection that is useful for surveillance and rapid clinical responses.
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Enfermedades de los Peces , Infecciones por Flavobacteriaceae , Oncorhynchus mykiss , Animales , Acuicultura , Enfermedades de los Peces/microbiología , Infecciones por Flavobacteriaceae/diagnóstico , Infecciones por Flavobacteriaceae/microbiología , Infecciones por Flavobacteriaceae/veterinaria , Flavobacterium/genética , Oncorhynchus mykiss/microbiología , ARN Ribosómico 16S/genéticaRESUMEN
Deception is a common feature of behavioral research design, although not commonly employed in the medical literature. It can promote scientific validity but is ethically controversial because it compromises subject autonomy and incurs additional costs. In this Point/Counterpoint monograph, we review the nature of deception in research and present arguments for and against its ethical use as a research methodology in behavioral studies. We describe the necessary guidelines, safeguards, and oversight, when deceptive methodology is considered, and report our experiences and lessons learned from conducting a multi-institutional audit study that relied upon deception of academic radiology faculty.
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Investigación Biomédica , Educación Médica , Investigación Conductal , Decepción , HumanosRESUMEN
Lactococcus garvieae is an emergent bacterial pathogen of salmonid fish in North America that causes acute infections particularly at water temperatures above 15°C. During 2020, L. garvieae was detected in rainbow trout, Onchorhyncus mykiss, cultured in Southern California and the Eastern Sierras. Infected fish exhibited high mortalities and nonspecific clinical signs of lethargy, erratic swimming, dark skin pigmentation, and exophthalmia. Macroscopic changes included external and internal hemorrhages, mainly in the eyes, liver, coelomic fat, intestine, and brain. Histological examination revealed splenitis, branchitis, panophthalmitis, hepatitis, enteritis, and coelomitis, with variable degrees of tissue damage among evaluated fish. Pure colonies of L. garvieae were isolated from infected trout and specific PCR primers for L. garvieae confirmed the preliminary diagnosis. Multilocus sequence analysis showed that the strains recovered from diseased trout represent a novel genetic group. Isolates were able to form biofilms within 24 h that increased their resistance to disinfection by hydrogen peroxide. Laboratory challenge methods for inducing lactococcosis in steelhead trout, O. mykiss, were evaluated by intracoelomic injection with serial dilutions of L. garvieae. The median lethal dose 21 days post challenge was â¼20 colony-forming units/fish. Experimentally infected trout presented similar clinical signs, gross changes, and microscopic lesions as those with natural disease, fulfilling Koch's postulates and demonstrating the high virulence of the recovered strains.
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Enfermedades de los Peces , Infecciones por Bacterias Grampositivas , Oncorhynchus mykiss , Animales , California/epidemiología , Enfermedades de los Peces/microbiología , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/veterinaria , Lactococcus , Oncorhynchus mykiss/microbiologíaRESUMEN
Edwardsiella piscicida is an emergent global fish pathogen with a wide host range, although host associations driving genetic diversity remain unclear. This study investigated the genetic and virulence diversity of 37 E. piscicida isolates recovered from 10 fish species in North America. Multilocus sequence analysis (MLSA) was conducted using concatenated alignments of the gyrB, pgi and phoU sequences. MLSA clustered the tested isolates into six discrete clades. In light of recent disease outbreaks in cultured salmonids, the virulence of each clade was evaluated in Chinook salmon Oncorhynchus tshawytscha fingerlings following intracoelomic challenge of ~106 CFU/fish. Challenged and control fish were monitored for 21d, and microbiological and histological examination was performed on dead and surviving fish. Peak mortality occurred 3-5 days post-challenge (dpc) regardless of isolate or genetic group. Edwardsiella piscicida was recovered from all moribund and dead animals. At 21 dpc, fish challenged with isolates from clades II, III and IV presented cumulative mortality ≥83.3%, whereas isolates from clade I, V and VI resulted in cumulative mortality ≤71.4%. This study suggests an underlying genetic basis for strain virulence and potential host associations. Further investigations using other fish models and variable challenge conditions are warranted.
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Edwardsiella/genética , Infecciones por Enterobacteriaceae/veterinaria , Enfermedades de los Peces/microbiología , Animales , Edwardsiella/patogenicidad , Infecciones por Enterobacteriaceae/genética , Infecciones por Enterobacteriaceae/microbiología , Infecciones por Enterobacteriaceae/mortalidad , Tipificación de Secuencias Multilocus , Salmón , Virulencia/genéticaRESUMEN
Several Francisella spp., including Francisella noatunensis, are regarded as important emerging pathogens of wild and farmed fish. However, very few studies have investigated the virulence factors that allow these bacterial species to be pathogenic in fish. The Francisella pathogenicity island (FPI) is a well-described, gene-dense region encoding major virulence factors for the genus Francisella. pdpA is a member of the pathogenicity-determining protein genes carried by the FPI that are implicated in the ability of the mammalian pathogen Francisella tularensis to escape and replicate in infected host cells. Using a sacB suicide approach, we generated pdpA knockouts to address the role of PdpA as a virulence factor for F. noatunensis. Because polarity can be an issue in gene-dense regions, we generated two different marker-based mutants in opposing polarity (the F. noatunensis subsp. orientalis ΔpdpA1 and ΔpdpA2 strains). Both mutants were attenuated (P < 0.0001) in zebrafish challenges and displayed impaired intracellular replication (P < 0.05) and cytotoxicity (P < 0.05), all of which could be restored to wild-type (WT) levels by complementation for the ΔpdpA1 mutant. Importantly, differences were found for bacterial burden and induction of acute-phase and proinflammatory genes for the F. noatunensis subsp. orientalis ΔpdpA1 and ΔpdpA2 mutants compared to the WT during acute infection. In addition, neither mutant resulted in significant histopathological changes. Finally, immunization with the F. noatunensis subsp. orientalis ΔpdpA1 mutant led to protection (P < 0.012) against an acute 40% lethal dose (LD40) challenge with WT F. noatunensis in the zebrafish model of infection. Taken together, the results from this study further demonstrate physiological similarities within the genus Francisella relative to their phylogenetic relationships and the utility of zebrafish for addressing virulence factors for the genus.
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Francisella/patogenicidad , Islas Genómicas , Pez Cebra/microbiología , Animales , Proteínas Bacterianas/genética , Enfermedades de los Peces/microbiología , VirulenciaRESUMEN
This article is a review of the highlights of pertinent literature published during the 12 months of 2020 that are of interest to the congenital cardiac anesthesiologist. After a search of the US National Library of Medicine's PubMed database, several topics emerged for which significant contributions were made in 2020. The authors of the present article considered the following topics noteworthy to be included in this review: pediatric cardiac care in the coronavirus disease 2019 era, the use of mechanical circulatory support in coronavirus disease 2019-related multisystem inflammatory syndrome in children, transfusion and coagulation management in children undergoing congenital heart surgery, and pulmonary vein stenosis.
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Anestesia en Procedimientos Quirúrgicos Cardíacos , COVID-19 , Cardiopatías Congénitas , Niño , Cardiopatías Congénitas/cirugía , Humanos , SARS-CoV-2 , Síndrome de Respuesta Inflamatoria SistémicaRESUMEN
BACKGROUND: Combined practice in pediatric anesthesiology (PA) and pediatric critical care medicine (PCCM) was historically common but has declined markedly with time. The reasons for this temporal shift are unclear, but existing evidence suggests that length of training is a barrier to contemporary trainees. Among current practitioners, restriction in dual-specialty practice also occurs, for reasons that are unknown at present. We sought to describe the demographics of this population, investigate their perceptions about the field, and consider factors that lead to attrition. METHODS: We conducted a cross-sectional, observational study of physicians in the United States with a combined practice in PA and PCCM. The survey was distributed electronically and anonymously to the distribution list of the Pediatric Anesthesia Leadership Council (PALC) of the Society for Pediatric Anesthesia (SPA), directing the recipients to forward the link to their faculty meeting our inclusion criteria. Attending-level respondents (n = 62) completed an anonymous, 40-question multidomain survey. RESULTS: Forty-seven men and 15 women, with a median age of 51, completed the survey. Major leadership positions are held by 44%, and 55% are externally funded investigators. A minority (26%) have given up one or both specialties, citing time constraints and politics as the dominant reasons. Duration of training was cited as the major barrier to entry by 77%. Increasing age and faculty rank and lack of a comparably trained institutional colleague were associated with attrition from dual-specialty practice. The majority (88%) reported that they would do it all again. CONCLUSIONS: The current cohort of pediatric anesthesiologist-intensivists in the United States is a small but accomplished group of physicians. Efforts to train, recruit, and retain such providers must address systematic barriers to completion of the requisite training and continued practice.
Asunto(s)
Anestesiólogos/normas , Anestesiología/normas , Actitud del Personal de Salud , Cuidados Críticos/normas , Pediatras/normas , Encuestas y Cuestionarios/normas , Adulto , Anestesiólogos/psicología , Anestesiología/métodos , Niño , Cuidados Críticos/métodos , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pediatras/psicología , Estados Unidos/epidemiologíaRESUMEN
INTRODUCTION: Lower urinary tract reconstruction in paediatric urology represents a physiologically stressful event that is associated with high complication rates, including readmissions and emergency room visits. Enhanced recovery after surgery (ERAS) protocol is a set of multidisciplinary, perioperative strategies designed to expedite surgical recovery without adversely impacting readmission or reoperation rates. Early paediatric urology data demonstrated ERAS reduced complications in this population. METHODS AND ANALYSIS: In 2016, a working group of paediatric urologists and anaesthesiologists convened to develop an ERAS protocol suitable for patients undergoing lower urinary tract reconstruction and define study process measures, patient-reported outcomes and clinically relevant outcomes in paediatric and adolescent/young adult patients. A multicentre, prospective, propensity-matched, case-control study design was chosen. Each centre will enrol five pilot patients to verify implementation. Subsequent enrolled patients will be propensity matched to historical controls. Eligible patients must be aged 4-25 years and undergoing planned operations (bladder augmentation, continent ileovesicostomy or appendicovesicostomy, or urinary diversion). 64 ERAS patients and 128 controls will be needed to detect a decrease in mean length of stay by 2 days. Pilot phase outcomes include attainment of ≥70% mean protocol adherence per patient and reasons for protocol deviations. Exploratory phase primary outcome is ERAS protocol adherence, with secondary outcomes including length of stay, readmissions, reoperations, emergency room visits, 90-day complications, pain scores, opioid usage and differences in Quality of Recovery 9 scores. ETHICS AND DISSEMINATION: This study has been registered with authors' respective institution review boards and will be published in peer-reviewed journals. It will provide robust insight into the feasibility of ERAS in paediatric urology, determine patient outcomes and allow for iteration of ERAS implementations as new best practices and evidence for paediatric surgical care arise. We anticipate this study will take 4 years to fully accrue with completed follow-up. TRIAL REGISTRATION NUMBER: NCT03245242; Pre-results.