76 research outputs found
Tests of Transfer Reaction Determinations of Astrophysical S-Factors
The reaction has been used to determine
asymptotic normalization coefficients for transitions to the ground and first
excited states of . The coefficients provide the normalization for
the tails of the overlap functions for and allow us
to calculate the S-factors for at astrophysical
energies. The calculated S-factors are compared to measurements and found to be
in very good agreement. This provides the first test of this indirect method to
determine astrophysical direct capture rates using transfer reactions. In
addition, our results yield S(0) for capture to the ground and first excited
states in , without the uncertainty associated with extrapolation from
higher energies.Comment: 6 pages, 2 figure
Regularities of ultrasonography of suspensions of alumina nanoparticles in biological media
Developing High Performance Lipoprotein Density Profiling for Use in Clinical Studies Relating to Cardiovascular Disease
Long-Term Implications of Atrial Fibrillation in Patients With Degenerative Mitral Regurgitation
Background: Scientific guidelines consider atrial fibrillation (AF) complicating degenerative mitral regurgitation (DMR) a debated indication for surgery. Objectives: This study analyzed the prognostic/therapeutic implications of AF at DMR diagnosis and long-term. Methods: Patients were enrolled in the MIDA (Mitral Regurgitation International Database) registry, which reported the consecutive, multicenter, international experience with DMR due to flail leaflets echocardiographically diagnosed. Results: Among 2,425 patients (age 67 \ub1 13 years; 71% male, 67% asymptomatic, ejection fraction 64 \ub1 10%), 1,646 presented at diagnosis with sinus rhythm (SR), 317 with paroxysmal AD, and 462 with persistent AF. Underlying clinical/instrumental characteristics progressively worsened from SR to paroxysmal to persistent AF. During follow-up, paroxysmal and persistent AF were associated with excess mortality (10-year survival in SR and in paroxysmal and persistent AF was 74 \ub1 1%, 59 \ub1 3%, and 46 \ub1 2%, respectively; p < 0.0001), that persisted 20 years post-diagnosis and independently of all baseline characteristics (p values <0.0001). Surgery (n = 1,889, repair 88%) was associated with better survival versus medical management, regardless of all baseline characteristics and rhythm (adjusted hazard ratio: 0.26; 95% confidence interval: 0.23 to 0.30; p < 0.0001) but post-surgical outcome remained affected by AF (10-year post-surgical survival in SR and in paroxysmal and persistent AF was 82 \ub1 1%, 70 \ub1 4%, and 57 \ub1 3%, respectively; p < 0.0001). Conclusions: AF is a frequent occurrence at DMR diagnosis. Although AF is associated with older age and more severe presentation of DMR, it is independently associated with excess mortality long-term after diagnosis. Surgery is followed by improved survival in each cardiac rhythm subset, but persistence of excess risk is observed for each type of AF. Our study indicates that detection of AF, even paroxysmal, should trigger prompt consideration for surgery
Panton-Valentine Leukocidin Does Play a Role in the Early Stage of Staphylococcus aureus Skin Infections: A Rabbit Model
Despite epidemiological data linking necrotizing skin infections with the production of Panton-Valentine leukocidin (PVL), the contribution of this toxin to the virulence of S. aureus has been highly discussed as a result of inconclusive results of in vivo studies. However, the majority of these results originate from experiments using mice, an animal species which neutrophils - the major target cells for PVL - are highly insensitive to the action of this leukocidin. In contrast, the rabbit neutrophils have been shown to be as sensitive to PVL action as human cells, making the rabbit a better experimental animal to explore the PVL role. In this study we examined whether PVL contributes to S. aureus pathogenicity by means of a rabbit skin infection model. The rabbits were injected intradermally with 108 cfu of either a PVL positive community-associated methicillin-resistant S. aureus isolate, its isogenic PVL knockout or a PVL complemented knockout strain, and the development of skin lesions was observed. While all strains induced skin infection, the wild type strain produced larger lesions and a higher degree of skin necrosis compared to the PVL knockout strain in the first week after the infection. The PVL expression in the rabbits was indirectly confirmed by a raise in the serum titer of anti-LukS-PV antibodies observed only in the rabbits infected with PVL positive strains. These results indicate that the rabbit model is more suitable for studying the role of PVL in staphylococcal diseases than other animal models. Further, they support the epidemiological link between PVL producing S. aureus strains and necrotizing skin infections
Combination of contrast with stress echocardiography: A practical guide to methods and interpretation
Contrast echocardiography has an established role for enhancement of the right heart Doppler signals, the detection of intra-cardiac shunts, and most recently for left ventricular cavity opacification (LVO). The use of intravenously administered micro-bubbles to traverse the myocardial microcirculation in order to outline myocardial viability and perfusion has been the source of research studies for a number of years. Despite the enthusiasm of investigators, myocardial contrast echocardiography (MCE) has not attained routine clinical use and LV opacification during stress has been less widely adopted than the data would support. The purpose of this review is to facilitate an understanding of the involved imaging technologies that have made this technique more feasible for clinical practice, and to guide its introduction into the practice of the non-expert user
Coronary microvascular resistance: methods for its quantification in humans
Coronary microvascular dysfunction is a topic that has recently gained considerable interest in the medical community owing to the growing awareness that microvascular dysfunction occurs in a number of myocardial disease states and has important prognostic implications. With this growing awareness, comes the desire to accurately assess the functional capacity of the coronary microcirculation for diagnostic purposes as well as to monitor the effects of therapeutic interventions that are targeted at reversing the extent of coronary microvascular dysfunction. Measurements of coronary microvascular resistance play a pivotal role in achieving that goal and several invasive and noninvasive methods have been developed for its quantification. This review is intended to provide an update pertaining to the methodology of these different imaging techniques, including the discussion of their strengths and weaknesses
Diversity of Staphylococcus aureus Isolates in European Wildlife
Staphylococcus aureus is a well-known colonizer and cause of infection among
animals and it has been described from numerous domestic and wild animal
species. The aim of the present study was to investigate the molecular
epidemiology of S. aureus in a convenience sample of European wildlife and to
review what previously has been observed in the subject field. 124 S. aureus
isolates were collected from wildlife in Germany, Austria and Sweden; they
were characterized by DNA microarray hybridization and, for isolates with
novel hybridization patterns, by multilocus sequence typing (MLST). The
isolates were assigned to 29 clonal complexes and singleton sequence types
(CC1, CC5, CC6, CC7, CC8, CC9, CC12, CC15, CC22, CC25, CC30, CC49, CC59, CC88,
CC97, CC130, CC133, CC398, ST425, CC599, CC692, CC707, ST890, CC1956, ST2425,
CC2671, ST2691, CC2767 and ST2963), some of which (ST2425, ST2691, ST2963)
were not described previously. Resistance rates in wildlife strains were
rather low and mecA-MRSA isolates were rare (n = 6). mecC-MRSA (n = 8) were
identified from a fox, a fallow deer, hares and hedgehogs. The common cattle-
associated lineages CC479 and CC705 were not detected in wildlife in the
present study while, in contrast, a third common cattle lineage, CC97, was
found to be common among cervids. No Staphylococcus argenteus or
Staphylococcus schweitzeri-like isolates were found. Systematic studies are
required to monitor the possible transmission of human- and livestock-
associated S. aureus/MRSA to wildlife and vice versa as well as the possible
transmission, by unprotected contact to animals. The prevalence of S.
aureus/MRSA in wildlife as well as its population structures in different
wildlife host species warrants further investigation
The effect of commonly used anticoccidials and antibiotics in a subclinical necrotic enteritis model
- …