scholarly journals Influence of Blood Collection Methods and Long-Term Plasma Storage on Quorum-Sensing Peptide Stability

ACS Omega ◽  
2020 ◽  
Vol 5 (26) ◽  
pp. 16120-16127
Author(s):  
Nathan Debunne ◽  
Anton De Spiegeleer ◽  
Dorian Depuydt ◽  
Yorick Janssens ◽  
Amélie Descamps ◽  
...  
Keyword(s):  
Quorum Sensing ◽  
Blood Collection ◽  
Peptide Stability ◽  
Collection Methods

scholarly journals Pseudomonas aeruginosa PA80 is a cystic fibrosis isolate deficient in RhlRI quorum sensing

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Syed A. K. Shifat Ahmed ◽  
Michelle Rudden ◽  
Sabrina M. Elias ◽  
Thomas J. Smyth ◽  
Roger Marchant ◽  
...  
Keyword(s):  
Cystic Fibrosis ◽  
Pseudomonas Aeruginosa ◽  
Quorum Sensing ◽  
Virulence Factors ◽  
Genomic Islands ◽  
Clinical Strain ◽  
Whole Genome ◽  
Synonymous Mutations ◽  
Wide Range

AbstractPseudomonas aeruginosa uses quorum sensing (QS) to modulate the expression of several virulence factors that enable it to establish severe infections. The QS system in P. aeruginosa is complex, intricate and is dominated by two main N-acyl-homoserine lactone circuits, LasRI and RhlRI. These two QS systems work in a hierarchical fashion with LasRI at the top, directly regulating RhlRI. Together these QS circuits regulate several virulence associated genes, metabolites, and enzymes in P. aeruginosa. Paradoxically, LasR mutants are frequently isolated from chronic P. aeruginosa infections, typically among cystic fibrosis (CF) patients. This suggests P. aeruginosa can undergo significant evolutionary pathoadaptation to persist in long term chronic infections. In contrast, mutations in the RhlRI system are less common. Here, we have isolated a clinical strain of P. aeruginosa from a CF patient that has deleted the transcriptional regulator RhlR entirely. Whole genome sequencing shows the rhlR locus is deleted in PA80 alongside a few non-synonymous mutations in virulence factors including protease lasA and rhamnolipid rhlA, rhlB, rhlC. Importantly we did not observe any mutations in the LasRI QS system. PA80 does not appear to have an accumulation of mutations typically associated with several hallmark pathoadaptive genes (i.e., mexT, mucA, algR, rpoN, exsS, ampR). Whole genome comparisons show that P. aeruginosa strain PA80 is closely related to the hypervirulent Liverpool epidemic strain (LES) LESB58. PA80 also contains several genomic islands (GI’s) encoding virulence and/or resistance determinants homologous to LESB58. To further understand the effect of these mutations in PA80 QS regulatory and virulence associated genes, we compared transcriptional expression of genes and phenotypic effects with isogenic mutants in the genetic reference strain PAO1. In PAO1, we show that deletion of rhlR has a much more significant impact on the expression of a wide range of virulence associated factors rather than deletion of lasR. In PA80, no QS regulatory genes were expressed, which we attribute to the inactivation of the RhlRI QS system by deletion of rhlR and mutation of rhlI. This study demonstrates that inactivation of the LasRI system does not impact RhlRI regulated virulence factors. PA80 has bypassed the common pathoadaptive mutations observed in LasR by targeting the RhlRI system. This suggests that RhlRI is a significant target for the long-term persistence of P. aeruginosa in chronic CF patients. This raises important questions in targeting QS systems for therapeutic interventions.

Evaluation of blood collection methods and anticoagulants for platelet function analyses on C57BL/6J laboratory mice

Platelets ◽  
2019 ◽  
Vol 31 (8) ◽  
pp. 981-988 ◽  
Author(s):  
Alexandra Grill ◽  
Klytaimnistra Kiouptsi ◽  
Cornelia Karwot ◽  
Kerstin Jurk ◽  
Christoph Reinhardt
Keyword(s):  
Platelet Function ◽  
Blood Collection ◽  
Laboratory Mice ◽  
Collection Methods

Comparison of a closed system and an open system for blood collection in feline donors

2020 ◽  
Vol 22 (12) ◽  
pp. 1121-1128
Author(s):  
Marie Binvel ◽  
Julie-Hélène Fairbrother ◽  
Valérie Lévesque ◽  
Marie-Claude Blais
Keyword(s):  
Open System ◽  
Closed System ◽  
Bacterial Contamination ◽  
Blood Donors ◽  
Blood Collection ◽  
Significant Difference ◽  
The Mean ◽  
Collection Methods ◽  
Time Point

Objectives This research aimed to evaluate the performance of a closed blood collection system and to compare it with an open system in terms of feasibility, tolerability by the donor, quality of blood collected and bacterial contamination. Methods Eight feline blood donors were prospectively and randomly subjected to both collection methods. Heart rate (HR), respiratory rate (RR) and blood pressure (BP) were evaluated before sedation, after sedation and after blood collection. The duration of the donation, the formation of a hematoma, and the degree of hemolysis and packed cell volume (PCV) of each blood unit were evaluated. Aliquot samples were aseptically collected from each unit and tested for bacterial contamination by culture and PCR on days 0, 14 and 28 of storage. Results There was no significant difference between collection methods for HR and RR at any time point. Before sedation, the mean systolic BP was significantly higher with the closed system (closed 169 mmHg, open 137 mmHg; P = 0.003). The average duration of collection was significantly shorter with the closed system (closed 3 mins 10 s, open 8 mins; P = 0.035); however, the prevalence of a successful blood collection with a single venipuncture and hematoma formation were not significantly different between systems. The mean unit PCV was significantly higher with the open system (closed 31%, open 34%; P = 0.026). On bacterial culture, 15/16 units were negative at all time points (closed 7; open 8). Using PCR, 5/16 units were positive for Ralstonia species for at least one time point (closed 3; open 2). Conclusions and relevance Our designed closed system appears to be well adapted to feline blood collection and was well tolerated by the donors, performing similarly to an open system, and could represent a valuable clinical device for the development of a feline blood bank, namely feline blood storage.

scholarly journals UNICANCER: French prospective cohort study of treatment-related chronic toxicity in women with localised breast cancer (CANTO)

ESMO Open ◽  
2019 ◽  
Vol 4 (5) ◽  
pp. e000562 ◽  
Author(s):  
Ines Vaz-Luis ◽  
Paul Cottu ◽  
Christel Mesleard ◽  
Anne Laure Martin ◽  
Agnes Dumas ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cohort Study ◽  
Patient Reported Outcomes ◽  
Breast Conserving Surgery ◽  
Blood Collection ◽  
Long Term Effects ◽  
Adjuvant Trastuzumab ◽  
Patient Reported ◽  
Prospective Longitudinal

BackgroundCorresponding with improved survival among patients with breast cancer, the awareness of the long-term effects of cancer treatments has increased. CANcer TOxicities (CANTO) aims to identify predictors of development and persistence of long-term toxicities in patients treated for stages I–III breast cancer and to characterise their incidence, as well their impact. In this paper, we describe the methodology used in this study and provide a first characterisation of the study population.MethodsCANTO (NCT01993498) is a French prospective, longitudinal cohort study enrolling patients with invasive cT0-cT3cN0-3M0 breast cancer of 26 French cancer centres. Patients are assessed at diagnosis, 3–6 (M0), 12 (M12), 36 (M36) and 60 (M60) months after completion of primary surgery, chemotherapy or radiotherapy whichever comes last. CANTO collects clinical, treatment, toxicity data, an extensive list of validated patient-reported outcomes (focusing on quality of life, psychological and behavioural questionnaires) and ad hoc socioeconomic questionnaires. Blood collection is performed at diagnosis, M0, M12, M36 and M60. Biologic sub-studies are ongoing (eg, microbiotic and cognitive sub-study).ResultsEnrolment started in 2012; by October 2018, 12 012 patients had been enrolled. Data collected have a low missing completion rate (<5% for key clinical variables, <20% for patient-reported outcomes). Blood, serum and plasma samples are stored in over 96% of patients. Among the first 5801 patients enrolled in CANTO, 76.7% of patients had hormone receptor positive and human epidermal growth factor 2 negative tumours; 73.1% of patients had breast conserving surgery; 90.4% received adjuvant radiotherapy, 53.4% (neo) adjuvant chemotherapy, 11.3% adjuvant trastuzumab and 80.3% adjuvant hormonotherapy.ConclusionsCANTO represents a unique opportunity to explore important medical, biological and psychosocial outcomes on breast cancer survivor population.

Effects of corticosterone on the secretion of corticotrophin-releasing factor, arginine vasopressin and oxytocin into hypophysial portal blood in long-term hypophysectomized rats

1991 ◽  
Vol 129 (1) ◽  
pp. 91-98 ◽  
Author(s):  
W. J. Sheward ◽  
G. Fink
Keyword(s):  
Arginine Vasopressin ◽  
Portal Blood ◽  
Blood Collection ◽  
Continuous Administration ◽  
Feedback Effects ◽  
Corticotrophin Releasing Factor ◽  
Hypophysectomized Rats ◽  
Hypophysial Portal ◽  
Intact Rats

ABSTRACT To investigate the feedback effects of corticosterone on the secretion of corticotrophin-releasing factor-41 (CRF-41), oxytocin and arginine vasopressin (AVP), hypophysial portal vessel blood was collected from control (intact) and long-term (6–8 weeks) hypophysectomized rats. In preliminary experiments in rats anaesthetized with urethane, long-term hypophysectomy resulted in a significant increase in the secretion of oxytocin and AVP; the hypothalamic contents of oxytocin and AVP were also increased in comparison with pituitary-intact rats. In long-term hypophysectomized rats anaesthetized with sodium pentobarbitone, but not with urethane, the output of CRF-41 into portal blood was increased twofold in comparison with that in control rats. In long-term hypophysectomized rats anaesthetized with pentobarbitone, the i.v. infusion of corticosterone (7·2 nmol/min) for a 2 h period of portal blood collection did not alter the secretion of CRF-41, oxytocin or AVP into portal blood; however, the secretion of CRF-41 and, to a lesser extent, AVP was significantly reduced in hypophysectomized rats by continuous corticosterone replacement, by a pellet of corticosterone implanted s.c. for 5 days before portal blood collection. These results confirm that the secretion of CRF-41 is differently affected by the anaesthetics urethane and pentobarbitone, and in long-term hypophysectomized rats show (i) that there were no apparent feedback effects of corticosterone infusion over a 2 h period on the secretion of any of the peptides studied, (ii) that late delayed feedback effects of continuous administration of corticosterone are mediated by a reduction in CRF-41 and AVP output, and (iii) that corticosterone has no effects on oxytocin secretion into portal blood. Journal of Endocrinology (1991) 129, 91–98

scholarly journals Forced posture of neurology residents in daily routine on the ward in Germany

2021 ◽  
Author(s):  
Daniela Ohlendorf ◽  
Anne Bijanzadeh ◽  
Ingo Hermanns ◽  
Rolf Ellegast ◽  
Laura Fraeulin ◽  
...  
Keyword(s):  
Working Time ◽  
Blood Collection ◽  
Computer Assisted ◽  
Daily Routine ◽  
Office Work ◽  
Daily Work ◽  
Total Percentage ◽  
Computer Based ◽  
Neutral Posture

Abstract Background The aim of this pilot study was to analyze the work of neurologists regarding static posture (> 4 s) and to identify awkward postures. Methods A total of 9 neurologists (assistant physicians; 3 male, 6 female) participated in this study. Kinematic data were collected using the computer-assisted acquisition and long-term analysis of musculoskeletal loads (CUELA; IFA, Sankt Augustin, Germany) system. Daily work (“office work,” “measures on patients,” and “other activities”) was analyzed with a computer-based task analysis. Results During ”measures on patients,” more than 80% of the total percentage of non-neutral posture was assumed with a flexed position of the head and entire back, both during “blood collection” (4.7% of the time) and while “placing intravenous catheters” (8.3% of the time). In contrast, long static postures (> 30 s) in the head and neck area, including the thoracic spine, were adopted during “office work.” Despite the increased total percentage of non-neutral attitudes during measures on patients, the time share of 3.4% of the total working time is so small that the risk for developing musculoskeletal disorders (MSD) is negligible. In contrast, office work, which comprises 50.8% of the total working time and longer static postures, has a potential risk for the development of MSD. Conclusion The present study is the first kinematic pilot analysis in the field of in-patient neurological assistants. Non-neutral as well as static postures in everyday work could be identified. Potential MSD can be reduced by optimizing the working height and by taking regular breaks to loosen the musculoskeletal system.

scholarly journals Evolution of the quorum sensing regulon in cooperating populations of Pseudomonas aeruginosa

2021 ◽  
Author(s):  
Nicole E Smalley ◽  
Amy L Schaefer ◽  
Kyle L Asfahl ◽  
Crystal Perez ◽  
E Peter Greenberg ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Quorum Sensing ◽  
Cell Communication ◽  
Opportunistic Pathogen ◽  
Quorum Quenching ◽  
Homoserine Lactone ◽  
Rna Seq ◽  
Bacterial Strains ◽  
Communication And Coordination

The bacterium Pseudomonas aeruginosa is an opportunistic pathogen and it thrives in many different saprophytic habitats. In this bacterium acyl-homoserine lactone quorum sensing (QS) can activate expression of over 100 genes, many of which code for extracellular products. P. aeruginosa has become a model for studies of cell-cell communication and coordination of cooperative activities. We hypothesized that long-term growth of bacteria under conditions where only limited QS-controlled functions were required would result in a reduction in the size of the QS-controlled regulon. To test this hypothesis, we grew P. aeruginosa for about 1000 generations in a condition in which expression of QS-activated genes is required for growth. We compared the QS regulons of populations after about 35 generations to those after about 1000 generations in two independent lineages by using quorum quenching and RNA-seq technology. In one evolved lineage the number of QS-activated genes identified was reduced by about 70% and in the other by about 45%. Our results lend important insights about the variations in the number of QS-activated genes reported for different bacterial strains and, more broadly, about the environmental histories of P. aeruginosa.

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