A National Registry for People With All Stages of Kidney Disease: The National Kidney Foundation (NKF) Patient Network.

RATIONALE & OBJECTIVE: The National Kidney Foundation (NKF) launched the first national US kidney disease patient registry, the NKF Patient Network, that is open to patients throughout the continuum of chronic kidney disease (CKD). The Network provides individualized education and will facilitate patient-centered research, clinical care, and health policy decisions. Here, we present the overall design and the results of a feasibility study that was conducted July through December 2020. STUDY DESIGN: Longitudinal observational cohort study of patient-entered data with or without electronic health care record (EHR) linkage in collaboration with health systems. SETTING & PARTICIPANTS: People with CKD, age≥18 years, are invited through their provider, NKF communications, or national outreach campaign. People self-enroll and share their data through a secure portal that offers individualized education and support. The first health system partner is Geisinger. EXPOSURE: Any cause and stage of CKD, including dialysis and kidney transplant recipients. OUTCOME: Feasibility of the EHR data transfer, participants' characteristics, and their perspectives on usability and content. ANALYTICAL APPROACH: Data were collected and analyzed through the registry portal powered by the Pulse Infoframe healthie 2.0 platform. RESULTS: During the feasibility study, 80 participants completed their profile, and 42 completed a satisfaction survey. Mean age was 57.5 years, 51% were women, 83% were White, and 89% were non-Hispanic or Latino. Of the participants, 60% were not aware of their level of estimated glomerular filtration rate and 91% of their urinary albumin-creatinine ratio. LIMITATIONS: Challenges for the Network are lack of awareness of kidney disease for many with CKD, difficulty in recruiting vulnerable populations or those with low digital readiness, and loss to follow-up, all leading to selection bias. CONCLUSIONS: The Network is positioned to become a national and international platform for real-world data that can inform the development of patient-centered research, care, and treatments.

Prevalence of Antimicrobial Resistant and Extended-Spectrum Beta-Lactamase-producing Escherichia coli in Dairy Cattle Farms in East Tennessee.

Antimicrobials have been widely used in dairy farms to prevent and control dairy cattle diseases since 1960s. This led to the emergence of antimicrobial resistant bacteria (ARB) that, along with their antimicrobial resistance genes (ARGs), can spread from dairy farms to humans. Therefore, regular antimicrobial resistance (AMR) monitoring is important to implement proper mitigation measures. The objective of this study was to determine the prevalence of AMR and extended-spectrum beta-lactamases (ESBLs)-producing Escherichia coli in dairy cattle. A cross-sectional study was conducted in four dairy cattle farms (A-D) in East Tennessee. A total of 80 samples consisting of 20 samples each of bulk tank milk, feces, dairy cattle manure-amended soil, and prairie soil adjacent to the farms were collected and cultured for the isolation of E. coli. Tetracycline (TETr)-, third-generation cephalosporin (TGCr)- and nalidixic acid (NALr)-resistant E. coli (n = 88) were isolated and identified on agar media supplemented with TET, cefotaxime, and NAL, respectively. TGCr E. coli were tested for ESBLs and other coselected ARGs. TETr (74%, n = 88) was the most common, followed by TGCr (20%) and NALr (8%). Farms had significant (p < 0.001) differences: the highest prevalence of TGCr (55%) and TETr (100%) were observed in farm D, while all NALr isolates were from farm C. Over 83% of TGCr isolates (n = 18) harbored ESBL gene blaCTX-M. Majority (78%) of the E. coli isolates were multidrug-resistant (MDR), being positive for beta-lactams (blaCTX-M), TETs tet(A), tet(B), tet(M)), sulfonamides (sul2), aminoglycosides (strA), and phenicols (floR). This study indicated the widespread occurrence of MDR ESBLs-E. coli in dairy cattle farms. AMR surveillance of more dairy farms and identification of farm-level risk factors are important to mitigate the occurrence and spread of ARB of significant public health importance, such as ESBLs-E. coli.

Genetic diversity and virulence characteristics of Staphylococcus aureus isolates from cases of bovine mastitis.

Staphylococcus aureus is one of the major bacterial mastitis pathogens with significant effects on animal and human health. Some studies showed that S. aureus strains that infect different host species are genetically distinct, although most strains can infect a wide range of host species. However, there are no clearly defined clonal patterns of S. aureus strains that are known to infect a specific host. The objectives of this study were to evaluate the clonal diversity and virulence characteristics of S. aureus isolates from cases of bovine mastitis. Bacteriological tests were conducted on milk samples from cases of bovine mastitis from 11 dairy farms including some milk samples from unknown farms in Eastern Tennessee. Overall, a total of 111 S. aureus were isolated and identified, and further evaluated for their genetic diversity by pulsed-field gel electrophoresis (PFGE) and virulence characteristics by PCR. Genotypic virulence factors including staphylococcal enterotoxins, and toxic shock syndrome toxin 1 (tsst-1) were tested by PCR. In addition, the association among several known virulence factors of these isolates based on our current and previous studies in our lab were evaluated. Previously generated data that were included in the analysis of association among virulence factors were the presence of biofilm production associated genes in the ica operon such as icaA, icaD and icaAB, and phenotypic virulence characteristics such as hemolysis on blood agar, slime production and resistance or susceptibility to ten commonly used antimicrobials in dairy farms. The PFGE results showed the presence of 16 PFGE types (designated A - P) throughout farms, of which three pulsotypes, I, M and O were the most frequently isolated PFGE types from most farms. The PFGE type M was the most prevalent of all 16 PFGE types, with 64 isolates being present among nine farms. The PCR results of enterotoxin genes showed that out of the total 111 tested 84 (75.7%) were negative whereas 13 (11.7%), 2 (1.8%), 3 (2.7%), 1 (0.9%) and 8 (7.2%) were positive for seb, seb and sec, sec, see, and tsst-1, respectively. All 111 isolates were negative for sea and sej. Results of the evaluation of I, M and O strains adhesion to and invasion into mammary epithelial cells showed that the total count of each strain of bacteria adhered to and invaded into mammary epithelial cell line (MAC-T cells) was not significantly different (P > 0.05). This may be an indication that there is no significant difference in their ability to establish early host-pathogen interaction and colonization of the host. There were no statistically significant associations among PFGE types and other known virulence factors of these strains. However, PFGE types O and M tend to cluster with ß-hemolysin, absence of enterotoxins and susceptibility to antimicrobials. In conclusion, there was not any association between pulsotype and genotypic and phenotypic virulence factors. S. aureus isolates from cases of bovine mastitis had diverse genotypes that possessed variable virulence factors.

Genome-wide association study identifies loci associated with milk leukocyte phenotypes following experimental challenge with Streptococcus uberis.

Mastitis is a detrimental disease in the dairy industry that decreases milk quality and costs upwards of $2 billion annually. Often, mastitis results from bacteria entering the gland through the teat opening. Streptococcus uberis is responsible for a high percentage of subclinical and clinical mastitis. Following an intramammary experimental challenge with S. uberis on Holstein cows (n = 40), milk samples were collected and somatic cell counts (SCC) were determined by the Dairy Herd Improvement Association Laboratory. Traditional genome-wide association studies (GWAS) have utilized test day SCC or SCC lactation averages to identify loci of interest. Our approach utilizes SCC collected following a S. uberis experimental challenge to generate three novel phenotypes: (1) area under the curve (AUC) of SCC for 0-7 days and (2) 0-28 days post-challenge; and (3) when SCC returned to below 200,000 cells/mL post-challenge (< 21 days, 21-28 days, or > 28 days). Polymorphisms were identified using Illumina's BovineSNP50 v2 DNA BeadChip. Associations were tested using Plink software and identified 16 significant (p < 1.0 × 10-4) single-nucleotide polymorphisms (SNPs) across the phenotypes. Most significant SNPs were in genes linked to cell signaling, migration, and apoptosis. Several have been recognized in relation to infectious processes (ATF7, SGK1, and PACRG), but others less so (TRIO, GLRA1, CELSR2, TIAM2, CPE). Further investigation of these genes and their roles in inflammation (e.g., SCC) can provide potential targets that influence resolution of mammary gland infection. Likewise, further investigation of the identified SNP with mastitis and other disease phenotypes can provide greater insight to the potential of these SNP as genetic markers.

Antimicrobial Resistance of Staphylococcus aureus Isolates from Dairy Cows and Genetic Diversity of Resistant Isolates.

Staphylococcus aureus is a frequent and major contagious mastitis bacterial pathogen. The antibiotic treatment cure rates vary considerably from 4% to 92%. Staphylococcus aureus readily becomes resistant to antibiotics, resulting in persistent noncurable intramammary infection that usually results in culling of infected animals. Because of its notorious ability to acquire resistance to the commonly used as well as last resort antimicrobials such as methicillin and vancomycin and the development of multidrug-resistant strains, antimicrobial resistance (AMR) in S. aureus is of paramount importance in human medicine. The objective of this study was to evaluate the prevalence of AMR and genetic diversity of S. aureus isolates from milk of dairy cattle. Staphylococcus aureus isolates (n = 239) from 33 dairy farms in Tennessee were tested against 10 antimicrobials by broth microdilution method using the Sensititer system. Genetic diversity of resistant isolates was evaluated by pulsed-field gel electrophoresis (PFGE). Overall, AMR of the S. aureus isolates varied from as low as 1.3% for ceftiofur to as high as 25% for sulfadimethoxine. Out of 239 S. aureus isolates, 82 (34.3%) of them were resistant to at least 1 of the 10 antimicrobials. The AMR isolates belonged to two major PFGE types, indicating the presence of dominant clonal patterns among the resistant isolates. In general, there was a variation of prevalence of AMR within and among farms over time, with an increasing trend in tetracycline resistance. Judicious use of antimicrobials in dairy cattle farms can reduce the development of antimicrobial-resistant S. aureus.

A single nucleotide in the promoter region modulates the expression of the ß-lactamase OXA-61 in Campylobacter jejuni.

OBJECTIVES: Despite prevalent ß-lactam resistance in Campylobacter jejuni, an important zoonotic enteric pathogen, the molecular basis of ß-lactamase-mediated ß-lactam resistance is still largely unknown. In particular, some C. jejuni strains that carry ß-lactamase gene blaOXA-61 (Cj0299) are still susceptible to ß-lactams with undetected ß-lactamase activity, suggesting blaOXA-61 is subjected to regulation. The objective of this study was to determine the regulatory mechanism of ß-lactamase in C. jejuni. METHODS: An ampicillin-resistant derivative of C. jejuni NCTC 11168 was subjected to whole genome sequencing and comparative genomics analysis. Complementary molecular experiments were further performed to examine the identified regulatory mechanism of blaOXA-61, which included complementation, promoter fusion assay, real-time RT-PCR, natural transformation using a defined PCR fragment, survey of clinical isolates and transcription start site mapping. RESULTS: A single nucleotide mutation (G → T transversion) upstream of blaOXA-61 was identified in the ampicillin-resistant derivative of NCTC 11168. The role of the G → T point mutation in acquired ß-lactam resistance through up-regulating the expression of blaOXA-61 was confirmed by multiple molecular approaches. The G → T transversion in the blaOXA-61 promoter was linked to high-level ß-lactam resistance in C. jejuni isolates. Transcription start site mapping indicated that the G → T transversion restored the TATA box in the -10 region of blaOXA-61. CONCLUSIONS: We demonstrated a novel genetic mechanism of ß-lactamase regulation in C. jejuni in this study, which will provide insights into the regulation and evolution of ß-lactam resistance in Campylobacter.

Efficacy of novel staphylococcal surface associated protein vaccines against Staphylococcus aureus and non-aureus staphylococcal mastitis in dairy cows.

Mastitis is an inflammation of the mammary gland commonly caused by bacteria or fungi. Staphylococcus aureus is a major bacterium that causes mastitis in dairy cows. Non-aureus staphylococci are also increasingly reported, with Staphylococcus chromogenes being the most common species. Current staphylococcal mastitis control programs are not fully effective, and treatment with antibiotics is not sustainable. Non-antibiotic sustainable control tools, such as effective vaccines, are critically needed. We previously developed S. aureus surface-associated proteins (SASP) and S. chromogenes surface-associated proteins (SCSP) vaccines that conferred partial protective effects. We hypothesized that vaccination with SASP or SCSP would reduce the incidence of S. aureus mastitis throughout the lactation period. The objective of this study was to evaluate the efficacy of SASP and SCSP vaccines against S. aureus and non-aureus staphylococcal mastitis under natural exposure over 300 days of lactation. Pregnant Holstein dairy cows (n = 45) were enrolled and assigned to receive SASP (n = 15) or SCSP (n = 16) vaccines or unvaccinated control (n = 14). Cows were vaccinated with 1.2 mg of SASP or SCSP with Emulsigen-D adjuvant. Control cows were injected with phosphate-buffered saline with Emulsigen-D adjuvant. Three vaccine injections were given subcutaneously at 60, 40, and 20 days before the expected calving. Booster vaccinations were given at 120 and 240 days in milk. Cows were monitored for mastitis at quarter and cow levels, staphylococcal mastitis incidence, changes in serum and milk anti-SASP and anti-SCSP antibody titers, bacterial counts in milk, adverse reactions, milk yield and milk somatic cells count over 300 days of lactation. The SCSP vaccine conferred a significant reduction in the incidence of staphylococcal mastitis. Milk and serum anti-SASP and anti-SCSP antibody titers were increased in the vaccinated cows compared to unvaccinated control cows. Anti-SASP and anti-SCSP antibody titers decreased at about 120 days in milk, indicating the duration of immunity of about four months. In conclusion, the SASP and SCSP vaccines conferred partial protection from natural infection.

A high-throughput antibody-based microarray typing platform.

Many rapid methods have been developed for screening foods for the presence of pathogenic microorganisms. Rapid methods that have the additional ability to identify microorganisms via multiplexed immunological recognition have the potential for classification or typing of microbial contaminants thus facilitating epidemiological investigations that aim to identify outbreaks and trace back the contamination to its source. This manuscript introduces a novel, high throughput typing platform that employs microarrayed multiwell plate substrates and laser-induced fluorescence of the nucleic acid intercalating dye/stain SYBR Gold for detection of antibody-captured bacteria. The aim of this study was to use this platform for comparison of different sets of antibodies raised against the same pathogens as well as demonstrate its potential effectiveness for serotyping. To that end, two sets of antibodies raised against each of the "Big Six" non-O157 Shiga toxin-producing E. coli (STEC) as well as E. coli O157:H7 were array-printed into microtiter plates, and serial dilutions of the bacteria were added and subsequently detected. Though antibody specificity was not sufficient for the development of an STEC serotyping method, the STEC antibody sets performed reasonably well exhibiting that specificity increased at lower capture antibody concentrations or, conversely, at lower bacterial target concentrations. The favorable results indicated that with sufficiently selective and ideally concentrated sets of biorecognition elements (e.g., antibodies or aptamers), this high-throughput platform can be used to rapidly type microbial isolates derived from food samples within ca. 80 min of total assay time. It can also potentially be used to detect the pathogens from food enrichments and at least serve as a platform for testing antibodies.

Isolation and characterization of Escherichia albertii originated from the broiler farms in Mississippi and Alabama.

Escherichia albertii is an emerging foodborne enteropathogen with increasing outbreaks worldwide, particularly in Japan recently. However, major features of this zoonotic pathogen, such as prevalence, virulence, and antibiotic resistance (AR), still remain under characterized. In a recent pilot study, we reported isolation of E. albertii from a chicken farm in Tennessee, suggesting chicken is an important reservoir for E. albertii. In this large-scale study, we examined prevalence of E. albertii in 9 farms in Mississippi and Alabama. Of a total of 270 cloacal swabs (30 per farm), 43 were PCR positive and 12 E. albertii strains were isolated with different isolation rates in individual farms ranging from 0 to 23.3 %. Both PFGE and whole genome analysis showed the E. albertii from different farms were phylogenetically distant, but those from the same farm displayed clonal relationships. Consistently, the antibiogram, AR gene profiles, and plasmid replicon types were similar across the strains in the same farm. Notably, 9 of the 12 E. albertii strains displayed multidrug resistance; one strain was even resistant to imipenem, a clinically important carbapenem antibiotic. In addition, comparative genomics analysis showed that two chicken E. albertii clusters displayed very close evolutionary relationships and similar virulence gene profiles to human E. albertii strains. In vitro growth assay demonstrated that the anti-enterobactin antibodies could dramatically inhibit the growth of two representative chicken E. albertii, supporting the feasibility of the novel enterobactin-based immune intervention for controlling this emerging pathogen. Taken together, the findings from this study further indicated chickens as an important reservoir for E. albertii in the U.S., highlighting the need to prevent and control E. albertii in poultry production.

Longitudinal surveillance and comparative characterization of Escherichia albertii in wild raccoons in the United States.

Escherichia albertii is an emerging enteric bacterial pathogen causing watery diarrhea, abdominal distension, vomiting and fever in humans. E. albertii has caused many foodborne outbreaks in Japan and was also reported in other countries worldwide. However, the important animal reservoirs of this pathogen are still largely unknown, impeding us to combat this emerging pathogen. Recently, we reported that wild raccoons (Procyon lotor) and broiler chickens are significant reservoirs of E. albertii in Japan and the U.S., respectively. Here, we performed a longitudinal surveillance to monitor prevalence of E. albertii in wild raccoons in the U.S. and conducted comprehensive comparative analyses of the E. albertii of different origins. A total of 289 fecal swab samples were collected from wild raccoons in Tennessee and Kentucky in the U.S. (2018-2020). Approximately 26% (74/289) of the raccoons examined were PCR-positive for E. albertii and eventually 22 E. albertii isolates were obtained. PFGE analysis showed the U.S. raccoon E. albertii were phylogenetically distant even though the corresponding raccoons were captured from a small area. Unlike the high prevalence of multidrug resistance (83%) observed in previous chicken E. albertii survey, antibiotic resistance was rarely observed in all the U.S. raccoon and 22 Japan raccoon strains with only one Japan strain displaying multidrug resistance (2%). Whole genome sequencing of 54 diverse E. albertii strains and subsequent comparative genomics analysis revealed unique clusters that displayed close evolutionary relationships and similar virulence gene profiles among the strains of different origins in terms of geographical locations (e.g., U.S. and Japan) and hosts (raccoon, chicken, swine, and human). Challenge experiment demonstrated raccoon E. albertii strains could successfully colonize in the chicken intestine at 3 and 8 days postinfection. A pilot environmental survey further showed all the four tested water samples from Tennessee river were E. albertii-positive; two different E. albertii strains, isolated from a single water sample, showed close relationships to those of human origin. Together, the findings from this study provide new insights into the ecology, evolution, and pathobiology of E. albertii, and underscore the need to control the emerging E. albertii in a complex ecosystem using One Health approach.

A phase III, open-label, single-arm study of tenecteplase for restoration of function in dysfunctional central venous catheters.

PURPOSE: To evaluate, in a phase III, single-arm study, the safety and efficacy of the thrombolytic agent tenecteplase in restoring function to dysfunctional central venous catheters (CVCs). MATERIALS AND METHODS: Pediatric and adult patients with dysfunctional CVCs were eligible to receive as much as 2 mL (2 mg) of intraluminal tenecteplase, which was left to dwell in the CVC lumen for a maximum of 120 minutes. If CVC function was not restored at 120 minutes, a second dose was instilled for an additional 120 minutes. RESULTS: Tenecteplase was administered to 246 patients. Mean patient age was 44 years (range, 0-92 y); 72 patients (29%) were younger than 17 years of age. Chemotherapy was the most common reason for catheter insertion. Restoration of CVC function was achieved in 177 patients (72%) within 120 minutes after the first dose. After instillation of a maximum of two doses of tenecteplase, CVC function was restored in 200 patients (81%), with similar frequencies in pediatric (83%) and adult (80%) patients. Adverse events (AEs) were reported in 31 patients (13%); fever (2%), neutropenia (1%), and nausea (0.8%) were most common. One serious AE, an allergic hypersensitivity reaction, was judged to be related to tenecteplase and/or a chemotherapeutic agent that the patient was receiving concurrently. CONCLUSIONS: Consecutive administration of one or two doses of tenecteplase into CVCs showed efficacy in the restoration of catheter function in patients with dysfunctional CVCs.

Improvement of hemodialysis catheter function with tenecteplase: a phase III, open-label study: TROPICS 4.

Hemodialysis (HD) catheters are prone to thrombotic occlusion. We evaluated tenecteplase, a thrombolytic, for the treatment of dysfunctional HD catheters. Patients with tunneled HD catheters and blood flow rate (BFR) <300 mL/min received open-label tenecteplase (2 mg/lumen) for a 1 h intracatheter dwell. Treatment success was defined as BFR ≥ 300 mL/min and a ≥ 25 mL/min increase from baseline BFR, 30 min before and at the end of HD. Patients without treatment success at the end of the initial visit received another 2 mg dose of tenecteplase for an up to 72 h extended dwell. Of 223 enrolled patients, 34% (95% confidence interval [CI], 28-40%) had treatment success after a 1 h dwell. Mean (standard deviation [SD]) BFR change from baseline was 82 (124) mL/min. Treatment success in those who received extended-dwell tenecteplase (n = 116) was 49% (95% CI, 40-58%), with mean (SD) BFR change from baseline of 117 (140) mL/min. Reported targeted adverse events included five catheter-related bloodstream infections and one thrombosis. No intracranial hemorrhage, major bleeding, embolic events, or catheter-related complications were reported. Tenecteplase administered as a 1 h or 1 h plus extended dwell was associated with improved HD catheter function in the TROPICS 4 trial.

Antimicrobial Resistance of Major Bacterial Pathogens from Dairy Cows with High Somatic Cell Count and Clinical Mastitis.

Mastitis is the most prevalent and economically important disease caused by different etiological agents, which leads to increased somatic cell count (SCC) and low milk quality. Treating mastitis cases with antimicrobials is essential to reduce SCC and improve milk quality. Non-prudent use of antimicrobials in dairy farms increased the development of antimicrobial resistant bacteria. This study's objectives were (1) to isolate and identify etiological agents of mastitis and (2) to determine antimicrobial resistance profiles of bacterial isolates. A total of 174 quarter milk samples from 151 cows with high SCC and clinical mastitis from 34 dairy farms in Tennessee, Kentucky, and Mississippi were collected. Bacterial causative agents were determined by bacteriological and biochemical tests. The antimicrobial resistance of bacterial isolates against 10 commonly used antimicrobials was tested. A total of 193 bacteria consisting of six bacterial species, which include Staphylococcus aureus, Streptococcus uberis, Streptococcus dysgalactiae, Escherichia coli, Klebsiella oxytoca and Klebsiella pneumoniae were isolated. Staphylococcus aureus was the predominant isolate followed by Strep. spp., E. coli, and Klebsiella spp. Results of this study showed that Gram-negatives (E. coli and Klebsiella spp.) were more resistant than Gram-positives (Staph. aureus and Streptococcus spp.). Continuous antimicrobial resistance testing and identification of reservoirs of resistance traits in dairy farms are essential to implement proper mitigation measures.

Chronic Kidney Disease Testing Among At-Risk Adults in the U.S. Remains Low: Real-World Evidence From a National Laboratory Database.

OBJECTIVE: An estimated 37 million Americans have chronic kidney disease (CKD). Nearly 90% do not know about their condition because of low awareness about the importance of CKD testing and diagnosis among practitioners and people at risk for CKD. This study uses data from a national clinical laboratory to identify guideline-recommended CKD testing rates across the U.S. RESEARCH DESIGN AND METHODS: Patients with Laboratory Corporation of America Holdings (Labcorp) testing between 2013 and 2019 were defined as at risk for CKD if they had any testing ordered with diagnosis codes for diabetes and/or hypertension. Guideline-concordant CKD assessment was defined by estimated glomerular filtration rate (eGFR) and urine albumin-to-creatinine ratio (uACR) testing within the study year. RESULTS: We identified 28,295,982 at-risk patients (mean age 60.6 ± 14.8 years; 53.6% women): 16.2% had diabetes, 63.8% had hypertension, and 20.1% had both comorbidities. Of these, 80.3% did not receive guideline-concordant assessment during the study period. Furthermore, only 21.0% had uACR testing versus 89.6% with eGFR. CKD assessment occurred at least once in 28.7% of patients with diabetes, 10.5% of patients with hypertension, and 41.4% of patients with both conditions. In a state-by-state comparison, annual testing rates ranged from 5 to 30%. The nationwide rate increased modestly each year between 2013 and 2018 (from 10.7% to 15.2%). CONCLUSIONS: Despite guideline recommendations, testing for CKD with uACR and eGFR in U.S. adults with diabetes and hypertension is low in routine clinical care. These data highlight the need for strategies to improve routine CKD assessment nationwide.

Isolation and characterization of Escherichia albertii in poultry at the pre-harvest level.

Escherichia albertii, often misidentified as Escherichia coli, has become an emerging foodborne human enteric pathogen. However, the prevalence and major animal reservoirs of this significant pathogen are still not clear. Here, we performed comprehensive microbiological, molecular, comparative genomics and animal studies to understand the status and features of E. albertii in the US domestic and food animals. Although no E. albertii was identified in a total of 1,022 diverse E. coli strains isolated from pets and food animals in a retrospective screening, in a pilot study, E. albertii was successfully isolated from a broiler farm (6 out of 20 chickens). The chicken E. albertii isolates showed clonal relationship as indicated by both pulsed-field gel electrophoresis (PFGE) and whole-genome sequence analysis. The isolated chicken E. albertii displayed multidrug resistance; all the resistance determinants including the extended-spectrum beta-lactamase gene, carried by plasmids, could be conjugatively transferred to E. coli, which was further confirmed by S1-PFGE and Southern hybridization. Whole-genome sequence-based phylogenetic analysis showed the chicken E. albertii strains were phylogenetically close to those of human origins. Challenge experiment demonstrated that the E. albertii strains isolated from human and wild bird could successfully colonize in the chicken intestine. Together, this study, for the first time, reported the isolation of E. albertii in poultry at the pre-hrvest level. The findings from multi-tier characterization of the chicken E. albertii strains indicated the importance of chickens as a reservoir for E. albertii. A large scale of E. albertii survey in poultry production at the pre-harvest level is highly warranted in the future.

Understanding and Overcoming the Challenges Related to Cardiovascular Trials Involving Patients with Kidney Disease.

Cardiovascular disease is a prevalent and prognostically important comorbidity among patients with kidney disease, and individuals with kidney disease make up a sizeable proportion (30%-60%) of patients with cardiovascular disease. However, several systematic reviews of cardiovascular trials have observed that patients with kidney disease, particularly those with advanced kidney disease, are often excluded from trial participation. Thus, currently available trial data for cardiovascular interventions in patients with kidney disease may be insufficient to make recommendations on the optimal approach for many therapies. The Kidney Health Initiative, a public-private partnership between the American Society of Nephrology and the US Food and Drug Administration, convened a multidisciplinary, international work group and hosted a stakeholder workshop intended to understand and develop strategies for overcoming the challenges with involving patients with kidney disease in cardiovascular clinical trials, with a particular focus on those with advanced disease. These efforts considered perspectives from stakeholders, including academia, industry, contract research organizations, regulatory agencies, patients, and care partners. This article outlines the key challenges and potential solutions discussed during the workshop centered on the following areas for improvement: building the business case, re-examining study design and implementation, and changing the clinical trial culture in nephrology. Regulatory and financial incentives could serve to mitigate financial concerns with involving patients with kidney disease in cardiovascular trials. Concerns that their inclusion could affect efficacy or safety results could be addressed through thoughtful approaches to study design and risk mitigation strategies. Finally, there is a need for closer collaboration between nephrologists and cardiologists and systemic change within the nephrology community such that participation of patients with kidney disease in clinical trials is prioritized. Ultimately, greater participation of patients with kidney disease in cardiovascular trials will help build the evidence base to guide optimal management of cardiovascular disease for this population.

TROPICS 1: a phase III, randomized, double-blind, placebo-controlled study of tenecteplase for restoration of function in dysfunctional central venous catheters.

PURPOSE: To evaluate the efficacy and safety of the thrombolytic tenecteplase, a fibrin-specific recombinant tissue plasminogen activator, for restoring function to dysfunctional central venous catheters (CVCs). MATERIALS AND METHODS: In this double-blind, placebo-controlled study, eligible patients with dysfunctional nonhemodialysis CVCs were randomly assigned to two treatment arms. In the first arm (TNK-TNK-PBO), patients received an initial dose of intraluminal tenecteplase (TNK) (up to 2 mg), a second dose of tenecteplase if indicated, and a third placebo (PBO) dose. In the PBO-TNK-TNK arm, placebo was instilled first followed by up to two doses of tenecteplase, if needed, for restoration of catheter function. After administration of each dose, CVC function was assessed at 15, 30, and 120 minutes. RESULTS: There were 97 patients who received either TNK-TNK-PBO (n = 50) or PBO-TNK-TNK (n = 47). Within 120 minutes of initial study drug instillation, catheter function was restored to 30 patients (60%) in the TNK-TNK-PBO arm and 11 patients (23%) in the PBO-TNK-TNK arm, for a treatment difference of 37 percentage points (95% confidence interval 18-55; P = .0002). Cumulative restoration rates for CVC function increased to 87% after the second dose of tenecteplase in both study arms combined. Two patients developed a deep vein thrombosis (DVT) after exposure to tenecteplase; one DVT was considered to be drug related. No cases of intracranial hemorrhage, major bleeding, embolic events, catheter-related bloodstream infections, or catheter-related complications were reported. CONCLUSIONS: Tenecteplase was efficacious for restoration of catheter function in these study patients with dysfunctional CVCs.

Experimental Staphylococcus aureus Mastitis Infection Model by Teat Dipping in Bacterial Culture Suspension in Dairy Cows.

Mastitis is inflammation of mammary glands usually caused by bacteria such as Staphylococcus aureus. Dairy cows are susceptible to mastitis during early dry and transition periods. Effective vaccine is needed during these periods. One of the limitations to develop an effective vaccine against S. aureus is the absence of good infection model. Intramammary infusion (IMIF) with S. aureus has been used as an infection model to test vaccine efficacy. IMIF is reliable in causing mastitis, but it bypasses physical barriers, non-specific natural defenses, and immunity in the teat canal. IMIF also transfers a large number of bacteria into the intramammary area at once. The objective of this study was to develop S. aureus IMIF model that mimics natural infection. Eight Holstein dairy cows were randomly divided into two groups of experimental (n = 5) and control (n = 3) cows. All teats of experimental cows were dipped in S. aureus culture suspension, whereas that of control cows were dipped in phosphate-buffered saline. Results showed that four of five cows were infected with challenge strain by day 3 of the challenge. The remaining cow was infected with Staphylococcus chromogenes. In conclusion, an experimental S. aureus intramammary infection can be induced by teat dipping into bacterial suspension.

Comparison of clonal relatedness and antimicrobial susceptibility of fecal Escherichia coli from healthy dogs and their owners.

OBJECTIVE: To determine prevalence of within-household sharing of fecal Escherichia coli between dogs and their owners on the basis of pulsed-field gel electrophoresis (PFGE), compare antimicrobial susceptibility between isolates from dogs and their owners, and evaluate epidemiologic features of cross-species sharing by use of a questionnaire. SAMPLE POPULATION: 61 healthy dog-owner pairs and 30 healthy control humans. PROCEDURES: 3 fecal E coli colonies were isolated from each participant; PFGE profiles were used to establish relatedness among bacterial isolates. Susceptibility to 17 antimicrobials was determined via disk diffusion. A questionnaire was used to evaluate signalment, previous antimicrobial therapy, hygiene, and relationship with dog. RESULTS: A wide array of PFGE profiles was observed in E coli isolates from all participants. Within-household sharing occurred with 9.8% prevalence, and across-household sharing occurred with 0.3% prevalence. No behaviors were associated with increased clonal sharing between dog and owner. No differences were found in susceptibility results between dog-owner pairs. Control isolates were more likely than canine isolates to be resistant to ampicillin and trimethoprim-sulfamethoxazole. Owners and control humans carried more multdrug-resistant E coli than did dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Within-household sharing of E coli was detected more commonly than across-household sharing, but both direct contact and environmental reservoirs may be routes of cross-species sharing of bacteria and genes for resistance. Cross-species bacterial sharing is a potential public health concern, and good hygiene is recommended.