Histophilus somni myocarditis and leptomeningitis in feedlot cattle: case report and occurrence in South America

We investigated deaths in a group of feedlot steers in Argentina. The main findings in 3 steers autopsied were pulmonary congestion and edema, necrotizing myocarditis, pericarditis, suppurative leptomeningitis, and bronchopneumonia. Histophilus somni was detected by bacterial culture and immunohistochemistry in the hearts of the 3 animals. Partial sequences of the 16S rRNA gene of a H. somni isolate had 99% similarity with other H. somni sequences in GenBank. Most reports of H. somni septicemia in cattle originate from North America and western Europe. There is scant information about cardiac histophilosis in South America. A survey of diagnostic laboratory personnel in 7 South American countries documented various forms of bovine histophilosis in Argentina, Brazil, Uruguay, and Venezuela.

A case study on the re-establishment of the cyanolichen symbiosis: where do the compatible photobionts come from?

BACKGROUND AND AIMS

In order to re-establish lichen symbiosis, fungal spores must first germinate and then associate with a compatible photobiont. To detect possible establishment limitations in a sexually reproducing cyanolichen species, we studied ascospore germination, photobiont growth and photobiont association patterns in Pectenia plumbea.

METHODS

Germination tests were made with ascospores from 500 apothecia under different treatments, and photobiont growth was analysed in 192 isolates obtained from 24 thalli. We determined the genotype identity [tRNALeu (UAA) intron] of the Nostoc cyanobionts from 30 P. plumbea thalli from one population. We also sequenced cyanobionts of 41 specimens of other cyanolichen species and 58 Nostoc free-living colonies cultured from the bark substrate.

KEY RESULTS

Not a single fungal ascospore germinated and none of the photobiont isolates produced motile hormogonia. Genetic analyses revealed that P. plumbea shares Nostoc genotypes with two other cyanolichen species of the same habitat, but these photobionts were hardly present in the bark substrate.

CONCLUSIONS

Due to the inability of both symbionts to thrive independently, the establishment of P. plumbea seems to depend on Dendriscocaulon umhausense, the only cyanolichen species in the same habitat that reproduces asexually and acts as a source of appropriate cyanobionts. This provides support to the hypothesis about facilitation among lichens.

Lipid profile is associated with treatment regimen in a large cohort of children and adolescents with Type 1 diabetes mellitus: a study from the international SWEET database

AIMS

To examine the effect of pump vs injection therapy on the lipid profile of children with Type 1 diabetes mellitus.

METHODS

A cross-sectional analysis of the lipid profile of children aged ≤ 18 years with Type 1 diabetes mellitus from SWEET, an international diabetes registry, was conducted with a focus on the effect of treatment regimen. Dyslipidaemia was defined as LDL cholesterol ≥2.6 mmol/l or non-HDL cholesterol ≥3.1 mmol/l. LDL and non-HDL cholesterol values among 14 290 children (52% boys, 51% receiving pump therapy) from 60 SWEET centres were analysed by linear and logistic regression analysis adjusted for sex, age, diabetes duration, HbA_1c and BMI-standard deviation score group, region, and common interactions between age, sex, HbA_1c and BMI.

RESULTS

This study confirmed the established associations of increased lipids with female sex, age, diabetes duration, HbA_1c and BMI. LDL and non-HDL cholesterol levels were lower in the pump therapy group compared to the injection therapy group [LDL cholesterol: injection therapy 2.44 mmol/l (95% CI 2.42 to 2.46) vs pump therapy 2.39 mmol/l (95% CI 2.37-2.41), P<0.001; non-HDL cholesterol: injection therapy 2.88 mmol/l (95% CI 2.86 to 2.90) vs pump therapy 2.80 mmol/l (95% CI 2.78-2.82), both P<0.0001]. Similarly, the odds ratios for LDL cholesterol ≥2.6 mmol/l [0.89 (95% CI 0.82-0.97)] and non-HDL cholesterol ≥3.1 mmol/l [0.85 (0.78 to 0.93)] were significantly lower in the pump therapy group, even after all adjustments.

CONCLUSIONS

Our results indicate that pump therapy is associated with a better lipid profile.

Utility of platforms Viteks MS and Microflex LT for the identification of complex clinical isolates that require molecular methods for their taxonomic classification

Mass spectrometry has revolutionized the clinical microbiology field in America’s and Europe’s industrialized countries, for being a fast, reliable and inexpensive technique. Our study is based on the comparison of the performance of two commercial platforms, Microflex LT (Bruker Daltonics, Bremen, Germany) and Vitek MS (bioMérieux, Marcy l´Etoile, France) for the identification of unusual and hard-to-diagnose microorganisms in a Reference Laboratory in Argentina. During a four-month period (February–May 2018) the diagnostic efficiency and the concordance between both systems were assessed, and the results were compared with the polyphasic taxonomic identification of all isolates. The study included 265 isolates: 77 Gram-Negative Bacilli, 33 Gram-Positive Cocci, 40 Anaerobes, 35 Actinomycetales, 19 Fastidious Microorganisms and 61 Gram-Positive Bacilli. All procedures were practiced according to the manufacturer’s recommendations in each case by duplicate, and strictly in parallel. Other relevant factors, such as the utility of the recommended extraction protocols, reagent stability and connectivity were also evaluated. Both systems correctly identified the majority of the isolates to species and complex level (82%, 217/265). Vitex MS achieved a higher number of correct species-level identifications between the gram-positive microorganisms; however, it presented greater difficulty in the identification of non-fermenting bacilli and a higher number of incorrect identifications when the profile of the microorganism was not represented in the commercial database. Both platforms showed an excellent performance on the identification of anaerobic bacteria and fastidious species. Both systems enabled the fast and reliable identification of most of the tested isolates and were shown to be very practical for the user.

[Development and evaluation of an in-house database for quick identification of Burkholderia contaminans by MALDI-TOF MS]

MALDI-TOF (matrix assisted laser desorption ionization-time of flight) mass spectrometry (MS) proved to be a robust tool for the identification of numerous taxonomic groups. However, it has limitations. A key advantage of this technique is the flexibility for the incorporation of protein profiles of microorganisms not included in the commercial database. Due to the prevalence of Burkholderia contaminans in fibrocystic patients in Argentina and the fact that rapid and reliable microbiological diagnosis is crucial in them, MALDI-TOF MS emerges as a strategic tool. The aim of this work was to develop an additional database with peptide spectra of reference isolates of B. contaminans. This database demonstrated to be successful for the identification of 97% of the isolates analyzed. Therefore, MALDI-TOF MS with the extended database was a useful tool for the identification and differentiation of other related species to B. contaminans.

Risk assessment of antimicrobial resistance along the food chain through culture-independent methodologies

Antimicrobial resistance (AMR) represents a major challenge for Public Health and the scientific community, and requires immediate and drastic solutions. Acquired resistance to certain antimicrobials is already widespread to such an extent that their efficacy in the treatment of certain life-threatening infections is already compromised. To date, the emergence and spread of AMR has been attributed to the use, misuse or indiscriminate use of antibiotics as therapeutic drugs in human, animal and plant health, or as growth promoters in veterinary husbandry. In addition, there is growing concern over the possibility of AMR transmission via the food chain. Food processing environments could act as potential hotspots for AMR acquisition and spread. Indeed, biocide use and exposure to food-related stresses and food processing technologies could presumably act as selection pressures for increased microbial resistance against clinically relevant antibiotics. Global AMR surveillance is critical for providing the necessary information to form global strategies and to monitor the effectiveness of public health interventions as well as to detect new trends and emerging threats. Surveillance of AMR is currently based on the isolation of indicator microorganisms and the phenotypic characterisation of the strains isolated. However, this approach provides very limited information on the mechanisms driving AMR or on the presence and spread of AMR genes. Whole genome sequencing (WGS) of bacterial pathogens is a powerful tool that can be used for epidemiological surveillance, outbreak detection and infection control. In addition, whole metagenome sequencing (WMS) allows for the culture-independent analysis of complex microbial communities, providing useful information on the occurrence of AMR genes. Both approaches can be used to provide the information necessary for the implementation of quantitative risk assessment of AMR transmission routes along the food chain.

The combination of block copolymers and phospholipids to form giant hybrid unilamellar vesicles (GHUVs) does not systematically lead to "intermediate" membrane properties

In this work, the elasticity under stretching as well as the fluidity of Giant Hybrid Unilamellar Vesicles (GHUV) has been studied. The membrane structuration of these GHUVs has already been studied at the micro and nanoscale in a previous study of the team. These GHUVs were obtained by the association of a fluid phospholipid (POPC) and a triblock copolymer, poly(ethyleneoxide)-b-poly(dimethylsiloxane)-b-poly(ethyleneoxide). Although the architecture of triblock copolymers can facilitate vesicle formation, they have been scarcely used to generate GHUVs. We show, through micropipette aspiration and FRAP experiments, that the incorporation of a low amount of lipids in the polymer membrane leads to a significant loss of the toughness of the vesicle and subtle modification of the lateral diffusion of polymer chains. We discuss the results within the framework of the conformation of the triblock copolymer chain in the membrane and in the presence of lipid nanodomains.

Routine Stenting of Extravesical Ureteroneocystostomy in Kidney Transplantation: A Systematic Review and Meta-analysis

BACKGROUND

Although rare, major urologic complications (MUC) in kidney transplantation can cause significant morbidity, increased cost, and may even lead to graft loss. Ureteric stents are routinely used to prevent MUC, although complications related to their use have been reported. Here, we systematically reviewed the role of routine stenting in preventing MUC in kidney transplantation with extravesical ureteric implantation and performed a meta-analysis of 6 randomized controlled trials.

METHODS

A PubMed search was performed for studies on MUC and stents in kidney transplant recipients. Randomized controlled trials were shortlisted for the review following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. RevMan 5 was used for statistical analysis, and outcome analysis was done with Cochran-Mantel-Haenszel test using random effect model.

RESULTS

Six trials meeting the criteria were identified. Although stent use did not decrease the incidence of urinary leak (odds ratio [OR], 0.39; 95% CI, 0.14-1.11; P = .08) or obstruction (OR, 0.41; 95% CI, 0.13-1.24; P = .11), it was associated with a higher incidence of urinary tract infection (OR, 3.59; 95% CI, 1.33-9.75; P = .01).

CONCLUSION

In the present era of extravesical ureterovesical anastomosis, routine stenting has a limited role in decreasing major urologic complications and may be associated with higher incidence of urinary tract infections.

Sepsis secondary to complicated skin and soft tissue infection caused by Ignatzschineria indica. First case report in Latin America

Introduction

Ignatzschineria is a recently recognized genus associated with larvae infestation Members of this genus are pathogens infrequently implicated in human disease. During the last decade, fewer than 10 cases of infection with Ignatzchineria species have been reported around the world. Bacteria of the genera Ignatzchineria and Wohlfahrtiimonas have been isolated from larvae of the parasitic fly Wohlfahrtia magnifica, which is found in Europe, Asia and North Africa, and is associated with myiasis in several animal species, but rarely in humans.

Case presentation

We report the first case of sepsis associated with complicated skin and soft tissue infection caused by I. indica in Latin America.

Conclusion

The clinical and molecular findings in our report add information to the accumulating data on emerging pathogens of this type, their geographic distribution, the correlation between the emergence of infectious diseases and social and economic inequalities, as well as the effects of global climate changes on potentially unusual distribution of vectors. We consider that fly larvae should be regarded as a potential source of specific arthropod-borne bacterial systemic infections.

Thaw depth spatial and temporal variability at the Limnopolar Lake CALM-S site, Byers Peninsula, Livingston Island, Antarctica

A new Circumpolar Active Layer Monitoring (CALM) site was established in 2009 at the Limnopolar Lake watershed in Byers Peninsula, Livingston Island, Antarctica, to provide a node in the western Antarctic Peninsula, one of the regions that recorded the highest air temperature increase in the planet during the last decades. The first detailed analysis of the temporal and spatial evolution of the thaw depth at the Limnopolar Lake CALM-S site is presented here, after eight years of monitoring. The average values range between 48 and 29cm, decreasing at a ratio of 16cm/decade. The annual thaw depth observations in the 100×100 m CALM grid are variable (Variability Index of 34 to 51%), although both the Variance Coefficient and the Climate Matrix Analysis Residual point to the internal consistency of the data. Those differences could be explained then by the terrain complexity and node-specific variability due to the ground properties. The interannual variability was about 60% during 2009-2012, increasing to 124% due to the presence of snow in 2013, 2015 and 2016. The snow has been proposed here as one of the most important factors controlling the spatial variability of ground thaw depth, since its values correlate with the snow thickness but also with the ground surface temperature and unconfined compression resistance, as measured in 2010. The topography explains the thaw depth spatial distribution pattern, being related to snowmelt water and its accumulation in low-elevation areas (downslope-flow). Patterned grounds and other surface features correlate well with high thaw depth patterns as well. The edaphic factor (E=0.05842m²/°C·day; R²=0.63) is in agreement with other permafrost environments, since frozen index (F>0.67) and MAAT (<-2°C) denote a continuous permafrost existence in the area. All these characteristics provided the basis for further comparative analyses between others nearby CALM sites.

Intraoperative Portal Flow of Less Than 1 Liter per Minute After Orthotopic Liver Transplantation Is Not Associated Per Se With an Increased Rate of Early Graft Dysfunction

OBJECTIVE

The aim of this study was to determine whether a portal flow of <1,000 mL/min in orthotopic liver transplantation (OLT) is associated with a higher incidence of early graft dysfunction (EGD) and graft loss.

METHODS

A retrospective study was performed of 540 OLTs carried out consecutively from December 2004 to December 2013. Patients were divided into 2 groups: group A, portal flow <1,000 mL/min; and group B, portal flow >1,000 mL/min. We studied the incidence of EGD and graft survival. A subanalysis was performed to define the minimum acceptable portal flow/100 g of liver weight to reduce the development EGD and graft loss.

RESULTS

Group A included 29 patients and group B, 511 patients. Group A had significantly lower-weight donors and recipients, female recipients with cholestatic disease, lower MELD scores, and lower hepatic artery flow. EGD occurred in 7 patients in group A (24.1%) versus 101 patients in group B (19.8%; P = .43). No significant differences were found in 1- and 5-year graft survival. A portal flow of <80 mL/min/100 g of liver weight was related to a significantly higher risk of developing EGD (odds ratio, 4.35; 95% confidence interval [CI], 1.46-12.91; P = .008) and graft loss (hazard ratio, 4.05; 95% CI, 1.32-12.42; P = .014).

CONCLUSIONS

Intraoperative portal flow of <1,000 mL/min in OLT was not related per se with a higher incidence of EGD or graft loss. Significantly higher risk of developing EGD and graft loss was associated with a portal flow of <80 mL/min/100 g of liver weight.

Efficacy and Safety of Therapy With Simeprevir and Sofosbuvir in Liver Transplant Recipients Infected by Hepatitis C Virus Genotype 4: Cohort Spanish Society of Liver Transplantation Cohort

BACKGROUND

Patients with hepatitis C virus (HCV) genotype 4 infection are poorly represented in clinical trials of 2nd-generation direct-acting antivirals (DAAs), and more data are needed to help guide treatment decisions. We still have even fewer data concerning liver transplant patients. Simeprevir (SIM) and sofosbuvir (SOF) combination is useful to treat this genotype. The aim of this study was to know the efficacy and safety of the combination SIM + SOF ± ribavirin (RBV) in a group of liver transplant patients with HCV genotype 4 infection in Spain in real life.

METHODS

This was a multicenter retrospective study, including 28 HCV genotype 4 patients from 11 liver transplant centers who were treated with SIM + SOF ± RBV. We included in the analysis demographic, clinical, and virologic data and details of serious adverse events (SAEs), including mortality rate 6 months after treatment.

RESULTS

All patients were male, mean age 52 ± 9.43 years, and 50% were IL28B CT and 37.5% TT; 46.42% of them were pretreated and 76.9 were null responders. Fibrosis stage 4 was found in 38.7% of patients; in 67.8% of those cases the diagnosis of fibrosis was made with the use of Fibroscan, in 21.4% by liver biopsy. The average Fibroscan was 13.86 KPa. The average Model for End-Stage Liver Disease (MELD) score of cirrhotic patients was 10.9 and the Child-Pugh score was A in 70%, B in 20%, and C in 10%. We included RBV in 75% of patients, and treatment duration was 12 weeks in all patients. The sustained virologic response at week 12 (SVR12) was 95.23%. There were no discontinuations due to SAEs, but the mortality rate at 6 months after treatment was 7.14%. All deceased patients were cirrhotic, Child C, and with an average MELD score of 20.

CONCLUSIONS

The combination SIM + SOF ± RBV to treat HCV genotype 4 in liver transplant patients is an option with high rates of SVR12 and very safe, similarly to genotype 1. There was no treatment-related mortality, but when it is administered in advanced stages of fibrosis it may not be enough to prevent mortality associated with cirrhotic hepatitis C recurrence after transplantation.

Effectiveness and safety of ombitasvir, paritaprevir, ritonavir ± dasabuvir ± ribavirin: An early access programme for Spanish patients with genotype 1/4 chronic hepatitis C virus infection

Over the last 5 years, therapies for hepatitis C virus (HCV) infection have improved significantly, achieving sustained virologic response (SVR) rates of up to 100% in clinical trials in patients with HCV genotype 1. We investigated the effectiveness and safety of ombitasvir/paritaprevir/ritonavir±dasabuvir in an early access programme. This was a retrospective, multicentre, national study that included 291 treatment-naïve and treatment-experienced patients with genotype 1 or 4 HCV infection. Most patients (65.3%) were male, and the mean age was 57.5 years. The mean baseline viral load was 6.1 log, 69.8% had HCV 1b genotype, 72.9% had cirrhosis and 34.7% were treatment-naïve. SVR at 12 weeks posttreatment was 96.2%. Four patients had virological failure (1.4%), one leading to discontinuation. There were no statistical differences in virological response according to genotype or liver fibrosis. Thirty patients experienced serious adverse events (SAEs) (10.3%), leading to discontinuation in six cases. Hepatic decompensation was observed in five patients. Four patients died during treatment or follow-up, three of them directly related to liver failure. Multivariate analyses showed a decreased probability of achieving SVR associated with baseline albumin, bilirubin and Child-Pugh score B, and a greater probability of developing SAEs related to age and albumin. This combined therapy was highly effective in clinical practice with an acceptable safety profile and low rates of treatment discontinuation.

Mixing Block Copolymers with Phospholipids at the Nanoscale: From Hybrid Polymer/Lipid Wormlike Micelles to Vesicles Presenting Lipid Nanodomains

Hybrids, i.e., intimately mixed polymer/phospholipid vesicles, can potentially marry in a single membrane the best characteristics of the two separate components. The ability of amphiphilic copolymers and phospholipids to self-assemble into hybrid membranes has been studied until now on the submicrometer scale using optical microscopy on giant hybrid unilamellar vesicles (GHUVs), but limited information is available on large hybrid unilamellar vesicles (LHUVs). In this work, copolymers based on poly(dimethylsiloxane) and poly(ethylene oxide) with different molar masses and architectures (graft, triblock) were associated with 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC). Classical protocols of LUV formation were used to obtain nanosized self-assembled structures. Using small-angle neutron scattering (SANS), time-resolved Förster resonance energy transfer (TR-FRET), and cryo-transmission electron microscopy (cryo-TEM), we show that copolymer architecture and molar mass have direct influences on the formation of hybrid nanostructures that can range from wormlike hybrid micelles to hybrid vesicles presenting small lipid nanodomains.

Abstract P4-03-16: FAPα (fibroblast activation protein-α) analysis in breast tumor cells and stroma after neoadjuvant treatment

Background: FAPα is a transmembrane serine protease expressed on cancer associated fibroblast that promotes tumour growth and invasion. In patients (pts) with poor outcome and survival FAPα is highly overexpressed. FAPα is also expressed in stroma across all breast cancer subtypes without association with clinicopathological factors. Pts without Complete Pathological Response (pCR) after Neoadjuvant Chemotherapy (NC) had poor outcome. We analysed the relationship between the expression of FAPα in stroma (fibroblast) and in epithelial breast cancer cells of pts without pCR after NC (taxanes, antracyclines and trastuzumab in Her2+).

Methods: 60 pts were included. ER, PR and Ki67 were studied by IHQ (Ventana) and Her2 by FISH (PatnVysion). FAPα expression was determined by IHQ (polyclonal, Ventana). St Gallen guidelines for subtype of breast cancer were used.

Results: 53 pts had tissue. Median age 47 years (range 29-68). Median tumour size 43mm and 10 (18.9%) were multifocal. 37 (69.8%) had positive axillary nodes. 47 were ductal invasive carcinomas. 33 (62.3%) were grade 2 and 20 (37.7%) grade 3. 44 pts (83%) had ER+ (20 luminal B), 17 (32%) Her2+ and 6 (11%) triple negative(TN). Median Ki67 was 22% (p25-75:15-38%). Miller-Payne response was 1.9% G1 (1pt), 43.4% G2 (23 pts), 41.5% G3 (22 pts) and 13.2% G4 (7 pts). The recurrences were 2 local and 12 distant (26.4%). Median FAPα in residual epithelial breast cancer cells after NC was 85% (p25-75:30-95%) and in the stroma 20% (p25-75:10-62%). Median epithelial FAPα was 55% in TN, 85% Her2, 72.5% luminal A and 92.5% in luminal B. Median stromal FAPα was 52.5% in TN, 20% Her2, 15% luminal A and 15% in luminal B. There is not association between stromal FAPα and clinicopathological features, but a higher epithelial FAPα was found in tumours wih higher ER, PR and Ki67. In luminal B subtype, stromal FAPα was smaller in pts with relapses (median 7.5%) than without relapses (median 30%). Conclusions: Stromal FAPα in residual cancer after NC is higher in TN breast cancer but without association with relapses in our small sample. However, in luminal B subtype stromal FAPα is smaller in pts with relapses.

Citation Format: Calvo I, Prieto M, Suárez-Gauthier A, Pérez FJ, Hernández E, Acosta D, Cárdenas JM, López-Ríos F, Estévez LG. FAPα (fibroblast activation protein-α) analysis in breast tumor cells and stroma after neoadjuvant treatment [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-03-16.