Pneumococcal adherence to the nasopharyngeal epithelium is a critical step in colonisation and disease. The probiotic bacterium, Streptococcus salivarius, can inhibit pneumococcal adherence to ...epithelial cells in vitro. We investigated the mechanism(s) of inhibition using a human pharyngeal epithelial cell line (Detroit 562) following pre-administration of two different strains of S. salivarius.
Whilst the bacteriocin-encoding megaplasmids of S. salivarius strains K12 and M18 were essential to prevent pneumococcal growth on solid media, they were not required to inhibit pneumococcal adherence. Experiments testing S. salivarius K12 and two pneumococcal isolates (serotypes 19F and 6A) showed that inhibition of 19F may involve S. salivarius-mediated blocking of pneumococcal binding sites: a negative correlation was observed between adherence of K12 and 19F, and no inhibition occurred when K12 was prevented from contacting epithelial cells. K12-mediated inhibition of adherence by 6A may involve additional mechanisms, since no correlation was observed between adherence of K12 and 6A, and K12 could inhibit 6A adherence in the absence of cell contact.
These results suggest that S. salivarius employs several mechanisms, including blocking pneumococcal binding sites, to reduce pneumococcal adherence to pharyngeal epithelial cells. These findings extend our understanding of how probiotics may inhibit pneumococcal adherence and could assist with the development of novel strategies to prevent pneumococcal colonisation in the future.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Cardiovascular disease (CVD) is responsible for 50% of the excess mortality for patients with RA. This study aimed to evaluate a novel 8-week cognitive behavioural patient education intervention ...designed to effect behavioural change with regard to modifiable CVD risk factors in people with RA.
This was a non-blinded randomized controlled trial with a delayed intervention arm. Participants were randomly assigned to receive the cognitive behavioural education intervention or a control information leaflet at a ratio of 1:1. The primary outcome measure was patient's knowledge of CVD in RA; secondary measures were psychological measures relating to effecting behaviour change, actual behaviour changes and clinical risk factors. Data were collected at baseline, 2 and 6 months.
A total of 110 participants consented (52 in the intervention group and 58 in the control group) to participate in the study. At 6 months, those in the intervention group had significantly higher knowledge scores (P < 0.001); improved behavioural intentions to increase exercise (P < 0.001), eat a low-fat diet (P = 0.01) and lose weight (P = 0.06); and lower mean diastolic blood pressure by 3.7 mmHg, whereas the control group's mean diastolic blood pressure increased by 0.8 mmHg. There was no difference between the groups on actual behaviours.
Patient education has a significant role to play in CVD risk factor modification for patients with RA, and the detailed development of this programme probably contributed to its successful results. It is disappointing that behaviours, as we measured them, did not change. The challenge, as always, is how to translate behavioural intentions into action. Larger studies, powered specifically to look at behavioural changes, are required. Trial registration. National Institute for Health Research, UKCRN 4566.
Improvements in temporal resolution of single-photon detectors enable increased data rates and transmission distances for both classical and quantum optical communication systems, higher spatial ...resolution in laser ranging, and observation of shorter-lived fluorophores in biomedical imaging. In recent years, superconducting nanowire single-photon detectors (SNSPDs) have emerged as the most efficient time-resolving single-photon-counting detectors available in the near-infrared, but understanding of the fundamental limits of timing resolution in these devices has been limited due to a lack of investigations into the timescales involved in the detection process. We introduce an experimental technique to probe the detection latency in SNSPDs and show that the key to achieving low timing jitter is the use of materials with low latency. By using a specialized niobium nitride SNSPD we demonstrate that the system temporal resolution can be as good as 2.6 ± 0.2 ps for visible wavelengths and 4.3 ± 0.2 ps at 1,550 nm.Knowledge about detection latency provides a guideline to reduce the timing jitter of niobium nitride superconducting nanowire single-photon detectors. A timing jitter of 2.6 ps at visible wavelength and 4.3 ps at 1,550 nm is achieved.
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FZAB, GEOZS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Considerable human illness can be linked to the development of oral microbiota disequilibria. The predominant oral cavity commensal, Streptococcus salivarius has emerged as an important source of ...safe and efficacious probiotics, capable of fostering more balanced, health-associated oral microbiota. Strain K12, the prototype S. salivarius probiotic, originally introduced to counter Streptococcus pyogenes infections, now has an expanded repertoire of health-promoting applications. K12 and several more recently proposed S. salivarius probiotics are now being applied to control diverse bacterial consortia infections including otitis media, halitosis and dental caries. Other potential applications include upregulation of immunological defenses against respiratory viral infections and treatment of oral candidosis. An overview of the key steps required for probiotic development is also presented.
Cardiac deaths account for the largest share of on-duty firefighter deaths. To help ensure duty fitness and minimize injury risk, many fire departments require the passing of an annual physical ...ability test, consisting of a battery of simulated fire suppression activities (sFSAs). The purpose of the study was to determine the relationship of sFSA performance to acute cardiac and respiratory events (ACREs) and the effect that estimated VO2max has on sFSA performance. The study was retrospective. As part of an annual physical ability test, five timed sFSAs were performed, summed for a composite time, and categorized into three performance levels (fast, moderate, and slow). Estimated VO2max was determined using the Forestry Step Test. A significant (p = 0.023) linear trend was observed with higher sFSA performance times being associated with a higher proportion of firefighters going on to suffer an ACRE. The estimated VO2max was significantly (p < 0.001) higher in the fast group compared to the slow group. There was not a significant (p = 0.70) difference in estimated VO2max between the moderate and slow groups. Estimated VO2max performance and sFSA performance were significantly correlated, with rs(488) = −0.272 and p < 0.001. Poorer sFSA performance was found to be associated with a higher proportion of ACREs. The results suggest that sFSA performance may be a valid indicator of ACRE injury risk and aerobic capacity.
Synaptic vesicle protein 2 (SV2) is a membrane glycoprotein common to all synaptic and endocrine vesicles. Unlike many proteins involved in synaptic exocytosis, SV2 has no homology in yeast, ...indicating that it performs a function unique to secretion in higher eukaryotes. Although the structure and protein interactions of SV2 suggest multiple possible functions, its role in synaptic events remains unknown. To explore the function of SV2 in an in vivo context, we generated mice that do not express the primary SV2 isoform, SV2A, by using targeted gene disruption. Animals homozygous for the SV2A gene disruption appear normal at birth. However, they fail to grow, experience severe seizures, and die within 3 weeks, suggesting multiple neural and endocrine deficits. Electrophysiological studies of spontaneous inhibitory neurotransmission in the CA3 region of the hippocampus revealed that loss of SV2A leads to a reduction in action potential-dependent γ -aminobutyric acid (GABA)ergic neurotransmission. In contrast, action potential-independent neurotransmission was normal. Analyses of synapse ultrastructure suggest that altered neurotransmission is not caused by changes in synapse density or morphology. These findings demonstrate that SV2A is an essential protein and implicate it in the control of exocytosis.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
Probiotics developed for topical applications in humans have the potential to beneficially modulate microbial imbalances on the skin surface and thereby improve skin health. This study was conducted ...to determine whether topical formulations containing the human skin commensal Micrococcus luteus strain Q24 (BLIS Q24) are safe, tolerable and efficacious when used by healthy human subjects. M. luteus Q24 was assessed in vitro for haemolytic activity and its antibiotic susceptibility profile. Formulations of strain Q24 were evaluated for the preliminary safety and tolerability in healthy human participants. Forty-seven adults were randomly assigned to four single-site, single-blind randomised placebo or baseline controlled or active-controlled trials. Skin swab samples were collected for differential viable counts to monitor levels of probiotic colonisation. M. luteus Q24 was found to be non-haemolytic and susceptible to commonly used antibiotics. The M. luteus Q24 formulations were safe and tolerable and >90% of the participants reported improvements from baseline in the appearance (e.g., radiance and hydration) of their treated skin. Additionally, participants observed a reduction in pore size, skin clarity and enhanced skin softness. No adverse effects were reported. A dose-related significant increase was observed in the levels of M. luteus Q24 isolated from skin swabs of the probiotic-treated subjects. Placebo-controlled trials in human subjects involving the topical application of different doses of M. luteus Q24 formulations were supportive of the safety, tolerability and efficacy of probiotic M. luteus Q24. Self-reported skin health assessments by the subjects indicated that M. luteus Q24 has good potential as a probiotic for improving skin health quality.
Beef from retail and foodservice establishments in 11 US cities was evaluated using Warner–Bratzler shear (WBS) and consumer evaluation panels. Postmortem aging times ranged from 3 to 83
d for retail ...and 7 to 136
d for foodservice with mean aging times of 22.6
d and 30.1
d, respectively. For retail, the three cuts from the round – top round, bottom round, and eye of round – had the highest (
P
<
0.05) WBS values compared to cuts from the chuck, rib, and loin. Top loin steaks had the lowest (
P
<
0.05) WBS value compared to ribeye and top sirloin foodservice steaks. Retail bone-in top loin, top loin, ribeye, T-bone, and porterhouse received the highest (
P
<
0.05) ratings by consumers for overall like and like tenderness. Quality grade had little or no effect on foodservice sensory evaluations. Improvements in round tenderness are needed to increase consumer acceptability.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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