577 research outputs found
Effect of a daily dose of <i>Lactobacillus brevis</i> CD2 lozenges in high caries risk schoolchildren
Objectives A double-blind, randomised, placebo-controlled clinical trial was performed to validate the hypothesis that the use of lozenges containing Lactobacillus brevis CD2 (Inersan®, CD Investments srl) may reduce plaque pH, salivary mutans streptococci (ms) and bleeding on probing, during a 6-week period, in a sample of high caries risk schoolchildren.
Methods A total of 191 children (aged 6–8 years), presenting two to three carious lesions and a salivary ms concentration of ≥105 CFU/ml, were enrolled and divided into two groups, an L. brevis CD2 lozenge group and a no L. brevis lozenge group, and examined at baseline (t0), after 3 weeks (t1), after 6 weeks of lozenge use (t2) and 2 weeks after the cessation of lozenge use (t3). Plaque pH was assessed using the microtouch technique following a sucrose challenge. The area under the curve (AUC5.7 and AUC6.2) was recorded. Salivary ms were counted, and bleeding on probing was assessed.
Results At t0, the plaque-pH and ms concentration values were similar in both groups. Mean areas (AUC5.7 and
AUC6.2) were significantly greater in the control group at t1, t2 and t3. L. brevis CD2 lozenges significantly reduced salivary
ms concentrations and bleeding. The subjects from the
test group showed a statistically significant decrease (p=0.01)in salivary ms concentration. At t2, a statistically significantly lower bleeding value was recorded in the test group compared
with the control group (p=0.02).
Conclusions Six weeks’ use of lozenges containing L. brevis CD2 had a beneficial effect on some important variables related to oral health, including a reduction in plaque acidogenicity, salivary ms and bleeding on probing.</br
Implicit solvation using the superposition approximation (IS-SPA): extension to polar solutes in chloroform
Efficient, accurate, and adaptable implicit solvent models remain a significant challenge in the field of molecular simulation. A recent implicit solvent model, IS-SPA, based on approximating the mean solvent force using the superposition approximation, provides a platform to achieve these goals. IS-SPA was originally developed to handle non-polar solutes in the TIP3P water model but can be extended to accurately treat polar solutes in other polar solvents. In this manuscript, we demonstrate how to adapt IS-SPA to include the treatment of solvent orientation and long ranged electrostatics in a solvent of chloroform. The orientation of chloroform is approximated as that of an ideal dipole aligned in a mean electrostatic field. The solvent–solute force is then considered as an averaged radially symmetric Lennard-Jones component and a multipole expansion of the electrostatic component through the octupole term. Parameters for the model include atom-based solvent density and mean electric field functions that are fit from explicit solvent simulations of independent atoms or molecules. Using these parameters, IS-SPA accounts for asymmetry of charge solvation and reproduces the explicit solvent potential of mean force of dimerization of two oppositely charged Lennard-Jones spheres with high fidelity. Additionally, the model more accurately captures the effect of explicit solvent on the monomer and dimer configurations of alanine dipeptide in chloroform than a generalized Born or constant density dielectric model. The current version of the algorithm is expected to outperform explicit solvent simulations for aggregation of small peptides at concentrations below 150 mM, well above the typical experimental concentrations for these materials.Chemistr
A simplified immunoprecipitation method for quantitatively measuring antibody responses in clinical sera samples by using mammalian-produced Renilla luciferase-antigen fusion proteins
BACKGROUND: Assays detecting human antigen-specific antibodies are medically useful. However, the usefulness of existing simple immunoassay formats is limited by technical considerations such as sera antibodies to contaminants in insufficiently pure antigen, a problem likely exacerbated when antigen panels are screened to obtain clinically useful data. RESULTS: We developed a novel and simple immunoprecipitation technology for identifying clinical sera containing antigen-specific antibodies and for generating quantitative antibody response profiles. This method is based on fusing protein antigens to an enzyme reporter, Renilla luciferase (Ruc), and expressing these fusions in mammalian cells, where mammalian-specific post-translational modifications can be added. After mixing crude extracts, sera and protein A/G beads together and incubating, during which the Ruc-antigen fusion become immobilized on the A/G beads, antigen-specific antibody is quantitated by washing the beads and adding coelenterazine substrate and measuring light production. We have characterized this technology with sera from patients having three different types of cancers. We show that 20–85% of these sera contain significant titers of antibodies against at least one of five frequently mutated and/or overexpressed tumor-associated proteins. Five of six colon cancer sera tested gave responses that were statistically significantly greater than the average plus three standard deviations of 10 control sera. The results of competition experiments, preincubating positive sera with unmodified E. coli-produced antigens, varied dramatically. CONCLUSION: This technology has several advantages over current quantitative immunoassays including its relative simplicity, its avoidance of problems associated with E. coli-produced antigens and its use of antigens that can carry mammalian or disease-specific post-translational modifications. This assay should be generally useful for analyzing sera for antibodies recognizing any protein or its post-translational modifications
Implicit Solvation Using the Superposition Approximation (IS-SPA): Extension to Polar Solutes in Chloroform
Efficient, accurate, and adaptable implicit solvent models remain a
significant challenge in the field of molecular simulation. A recent implicit
solvent model, IS-SPA, based on approximating the mean solvent force using the
superposition approximation, provides a platform to achieve these goals. IS-SPA
was originally developed to handle non-polar solutes in the TIP3P water model
but can be extended to accurately treat polar solutes in other polar solvents.
In this manuscript, we demonstrate how to adapt IS-SPA to include the treatment
of solvent orientation and long ranged electrostatics in a solvent of
chloroform. The orientation of chloroform is approximated as that of an ideal
dipole aligned in a mean electrostatic field. The solvent--solute force is then
considered as an averaged radially symmetric Lennard-Jones component and a
multipole expansion of the electrostatic component through the octupole term.
Parameters for the model include atom-based solvent density and mean electric
field functions that are fit from explicit solvent simulations of independent
atoms or molecules. Using these parameters, IS-SPA accounts for asymmetry of
charge solvation and reproduces the explicit solvent potential of mean force of
dimerization of two oppositely charged Lennard-Jones spheres with high
fidelity. Additionally, the model more accurately captures the effect of
explicit solvent on the monomer and dimer configurations of alanine dipeptide
in chloroform than a generalized Born or constant density dielectric model. The
current version of the algorithm is expected to outperform explicit solvent
simulations for aggregation of small peptides at concentrations below 150 mM,
well above the typical experimental concentrations for these materials
CD94 and a Novel Associated Protein (94AP) Form a NK Cell Receptor Involved in the Recognition of HLA-A, HLA-B, and HLA-C Allotypes
AbstractWhereas the human killer cell inhibitory receptors (KIRs) for HLA class I are immunoglobulin-like monomeric type I glycoproteins, the murine Ly49 receptors for H-2 are type II homodimers of the C-type lectin superfamily. Here, we demonstrate that human NK cells also express C-type lectin receptors that influence recognition of polymorphic HLA-A, HLA-B, and HLA-C molecules. These receptors are heterodimers composed of CD94 chains covalently associated with novel tyrosine-phosphorylated glycoproteins (94AP). Some NK clones recognize a common HLA-C ligand using both KIRs and CD94–94AP receptors. These findings suggest the existence of human inhibitory MHC class I receptors of the immunoglobulin and C-type lectin superfamilies and indicate overlap in ligand specificity
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Musculoskeletal Injuries and Outcomes Pre- and Post- Emergency Medicine Training Program
Introduction: Musculoskeletal injuries (MSI) comprise a large portion of the trauma burden in low- and middle-income countries (LMIC). Rwanda recently launched its first emergency medicine training program (EMTP) at the University Teaching Hospital-Kigali (UTH-K), which may help to treat such injuries; yet no current epidemiological data is available on MSI in Rwanda.Methods: We conducted this pre-post study during two data collection periods at the UTH-K from November 2012 to July 2016. Data collection for MSI is limited and thus is specific to fractures. We included all patients with open, closed, or mixed fractures, hereafter referred to as MSI. Gathered information included demographics and outcomes including death, traumatic complications, and length of hospital stay, before and after the implementation of the EMTP.Results: We collected data from 3609 patients. Of those records, 691 patients were treated for fractures, and 674 of them had sufficient EMTP data measured for inclusion in the analysis of results (279 from pre-EMTP and 375 from post-EMTP). Patient demographics demonstrate that a majority of MSI cases are male (71.6% male vs 28.4% female) and young (64.3% below 35 years of age). Among mechanisms of injury, major causes included road traffic accidents (48.1%), falls (34.2%), and assault (6.0%). There was also an observed association between EMTP and trends of the three primary outcomes: a reduction of death in the emergency department (ED) from those with MSI by 89.9%, from 2.51% to 0.25% (p = 0.0077); a reduction in traumatic complications for MSI patients by 71.7%, from 3.58% to 1.01% (p = 0.0211); and a reduction in duration of stay in the ED among those with MSI by 52.7% or 2.81 days on average, from 5.33 to 2.52 days (p = 0.0437).Conclusion: This study reveals the current epidemiology of MSI morbidity and mortality for a major Rwandan teaching hospital and the potential impacts of EM training implementation among those with MSI. Residency training programs such as EMTP appear capable of reducing mortality, complications, and ED length of stay among those with MSI caused by fractures. Such findings underscore the efficacy and importance of investments in educating the next generation of health professionals to combat prevalent MSI within their communities
The SOS Pilot Study: a RCT of routine oxygen supplementation early after acute stroke—effect on recovery of neurological function at one week
Mild hypoxia is common after stroke and associated with poor long-term outcome. Oxygen supplementation could prevent hypoxia and improve recovery. A previous study of routine oxygen supplementation showed no significant benefit at 7 and 12 months. This pilot study reports the effects of routine oxygen supplementation for 72 hours on oxygen saturation and neurological outcomes at 1 week after a stroke
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