2,293 research outputs found
Characterization of the bacteriophage-derived endolysins PlySs2 and PlySs9 with in vitro lytic activity against bovine mastitis streptococcus uberis
Bovine mastitis, an infection of the cow’s mammary gland, is frequently caused by Streptococcus uberis and causes major economic losses in the dairy industry. The intramammary administration of antibiotics currently remains the predominant preventive and therapeutic measure. These antimicrobial compounds, ofwhich some are consideredcritical in human health care, are frequently applied as dry therapy resulting in their consistent overuse. Therefore, the use of antibiotics in the dairy sector is being questioned. We here identified two endolysins, i.e., PlySs2 and PlySs9, respectively derived from Streptococcus suis serotype-2 and -9 prophages, with lytic activity against S. uberis in an in vitro setting. Both endolysins gave clear lysis zones in spot-on-plate assays and caused a reduction of the optical density in a turbidity reduction assay. In depth characterization identified PlySs9 as the more potent endolysin over PlySs2 with a lower MIC value and about one additional log of killing. PlySs2 and PlySs9 were challenged to a panel of subclinical and clinical S. uberis milk isolates and were both able to lyse all strains tested. Molecular dissection of these endolysins in catalytic and cell wall binding subdomains resulted in major loss of killing and binding activity, respectively. Taken together, we here propose PlySs2 and PlySs9 as candidate compounds to the current antimicrobial arsenal known against bovine mastitis-causing S. uberis as future add-on or replacement strategy to the currently used intramammary antibiotics
Nucleons or diquarks? Competition between clustering and color superconductivity in quark matter
We study the instabilities of quark matter in the framework of a generalized
Nambu--Jona-Lasinio model, in order to explore possible competition between
three-quark clustering to form nucleons and diquark formation leading to color
superconductivity. Nucleon and solutions are obtained for the
relativistic Faddeev equation at finite density and their binding energies are
compared with those for the scalar and axial-vector diquarks found from the
Bethe-Salpeter equation. In a model with interactions in both scalar and axial
diquark channels, bound nucleons exist up to nuclear matter density. However,
except at densities below about a quarter of that of nuclear matter, we find
that scalar diquark formation is energetically favored. This raises the
question of whether a realistic phase diagram of baryonic matter can be
obtained from any model which does not incorporate color confinement.Comment: 23 pages (RevTeX), 5 figures (epsf
Randomized evaluation of fibrinogen versus placebo in complex cardiovascular surgery : post hoc analysis and interpretation of phase III results
OBJECTIVES: In a multicentre, randomized-controlled, phase III trial in complex cardiovascular surgery (Randomized Evaluation of Fibrinogen vs Placebo in Complex Cardiovascular Surgery: REPLACE), single-dose human fibrinogen concentrate (FCH) was associated with the transfusion of increased allogeneic blood products (ABPs) versus placebo. Post hoc analyses were performed to identify possible reasons for this result. METHODS: We stratified REPLACE results by adherence to the transfusion algorithm, pretreatment fibrinogen level (2g/l) and whether patients were among the first 3 treated at their centre. RESULTS: Patients whose treatment was adherent with the transfusion algorithm [FCH, n=47 (60.3%); placebo, n=57 (77.0%); P=0.036] received smaller quantities of ABPs than those with non-adherent treatment (P2g/l and fewer patients undergoing thoracoabdominal aortic aneurysm repair. CONCLUSIONS: None of the patient stratifications provided a clear explanation for the lack of efficacy seen for FCH in the REPLACE trial versus the positive phase II outcomes. However, together, the 3 factors demonstrated trends favouring FCH. Less familiarity with the protocol and procedures and unavoidable differences in the study populations may explain the differences seen between the phase II study and REPLACE.Peer reviewe
Risk Assessment for Patients with Chronic Respiratory Conditions in the Context of the SARS-CoV-2 Pandemic Statement of the German Respiratory Society with the Support of the German Association of Chest Physicians
Assessing the risk for specific patient groups to suffer from
severe courses of COVID-19 is of major importance in the
current SARS-CoV-2 pandemic. This review focusses on the
risk for specific patient groups with chronic respiratory conditions, such as patients with asthma, chronic obstructive
pulmonary disease, cystic fibrosis (CF), sarcoidosis, interstitial lung diseases, lung cancer, sleep apnea, tuberculosis,
neuromuscular diseases, a history of pulmonary embolism,
and patients with lung transplants. Evidence and recommendations are detailed in exemplary cases. While some patient
groups with chronic respiratory conditions have an increased risk for severe courses of COVID-19, an increasing
number of studies confirm that asthma is not a risk factor
for severe COVID-19. However, other risk factors such as
higher age, obesity, male gender, diabetes, cardiovascular
diseases, chronic kidney or liver disease, cerebrovascular
and neurological disease, and various immunodeficiencies
or treatments with immunosuppressants need to be taken
into account when assessing the risk for severe COVID-19 in
patients with chronic respiratory diseases
Colour reconnection in e+e- -> W+W- at sqrt(s) = 189 - 209 GeV
The effects of the final state interaction phenomenon known as colour
reconnection are investigated at centre-of-mass energies in the range sqrt(s) ~
189-209 GeV using the OPAL detector at LEP. Colour reconnection is expected to
affect observables based on charged particles in hadronic decays of W+W-.
Measurements of inclusive charged particle multiplicities, and of their angular
distribution with respect to the four jet axes of the events, are used to test
models of colour reconnection. The data are found to exclude extreme scenarios
of the Sjostrand-Khoze Type I (SK-I) model and are compatible with other
models, both with and without colour reconnection effects. In the context of
the SK-I model, the best agreement with data is obtained for a reconnection
probability of 37%. Assuming no colour reconnection, the charged particle
multiplicity in hadronically decaying W bosons is measured to be (nqqch) =
19.38+-0.05(stat.)+-0.08 (syst.).Comment: 30 pages, 9 figures, Submitted to Euro. Phys. J.
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