A systematic review of respect between acute care nurses and physicians.

BACKGROUND: Interprofessional collaboration between nurses and physicians has become an essential part of patient care, which, when lacking, can lead to well-known challenges. One possible explanation for ineffective nurse-physician collaboration is a lack of respect. PURPOSE: This review aims to enhance our understanding of the role of respect in work between nurses and physicians by synthesizing evidence about the conceptualization of respect, its mechanisms and outcomes, and its origins. METHODS: We performed a PRISMA-guided systematic literature review across five databases and reviewed 28 empirical studies about respect between nurses and physicians in acute care settings. FINDINGS: Research about respect between nurses and physicians varied in its conceptualization of respect in terms of its nature (as an attitude or behavior), its target (respect for individuals or groups), and its object (respect for task-relevant capabilities or human rights). The greatest convergence was on respect's object; the majority of studies focused on respect for task-relevant capabilities. The work reviewed offered insights into respect's potential mechanisms (attention and civility), outcomes (e.g., collaboration, patient outcomes, and provider outcomes such as job satisfaction), and origins (e.g., professional status and competence)-the latter suggesting how respect might be generated, developed, and maintained. PRACTICE IMPLICATIONS: Our review highlights a need to appreciate how respect for task-relevant capabilities relates to respect for human rights and what fosters each to avoid rewarding only one while hoping for both, allowing leaders to cultivate more effective nurse-physician collaborations and better patient and provider outcomes.

Conflict across representational gaps: Threats to and opportunities for improved communication.

Often, the senders and receivers of scientific communication have different knowledge bases. While such communication is essential for solving the complex social and technological problems that affect multiple stakeholders, a diversity of knowledge among communicators can create representational gaps (rGaps). rGaps occur when senders make assumptions that receivers do not, creating conflict over the meaning and value of the information communicated. Such conflict could, if managed, promote learning and innovation as communicators reconcile their assumptions. More often, however, rGaps cause conflict to transform from a debate that informs to an argument that divides. Managing rGap conflict so that it does not degrade communication requires relationship building to mitigate the negative by-products of persistent conflict while maintaining appropriate levels of cognitive distinctiveness among diverse stakeholders. Thus, we provide a framework for identifying and leveraging rGaps through managed conflict so that communication between those with different perspectives builds rather than burns bridges.

Quantitative magnetization transfer imaging of the human locus coeruleus.

The locus coeruleus (LC) is the major origin of norepinephrine in the central nervous system, and is subject to age-related and neurodegenerative changes, especially in disorders such as Parkinson's disease and Alzheimer's disease. Previous studies have shown that neuromelanin (NM)-sensitive MRI can be used to visualize the LC, and it is hypothesized that magnetization transfer (MT) effects are the primary source of LC contrast. The aim of this study was to characterize the MT effects in LC imaging by applying high spatial resolution quantitative MT (qMT) imaging to create parametric maps of the macromolecular content of the LC and surrounding tissues. Healthy volunteers (n = 26; sex = 17 F/9M; age = 41.0 ±â€¯19.1 years) underwent brain MRI on a 3.0 T scanner. qMT data were acquired using a 3D MT-prepared spoiled gradient echo sequence. A traditional NM scan consisting of a T1-weighted turbo spin echo sequence with MT preparation was also acquired. The pool-size ratio (PSR) was estimated for each voxel using a single-point qMT approach. The LC was semi-automatically segmented on the MT-weighted images. The MT-weighted images provided higher contrast-ratio between the LC and surrounding pontine tegmentum (PT) (0.215 ±â€¯0.031) than the reference images without MT-preparation (-0.005 ±â€¯0.026) and the traditional NM images (0.138 ±â€¯0.044). The PSR maps showed significant differences between the LC (0.090 ±â€¯0.009) and PT (0.188 ±â€¯0.025). The largest difference between the PSR values in the LC and PT was observed in the central slices, which also correspond to those with the highest contrast-ratio. These results highlight the role of MT in generating NM-related contrast in the LC, and should serve as a foundation for future studies aiming to quantify pathological changes in the LC and surrounding structures in vivo.

Longitudinal atlas for normative human brain development and aging over the lifespan using quantitative susceptibility mapping.

Longitudinal brain atlases play an important role in the study of human brain development and cognition. Existing atlases are mainly based on anatomical features derived from T1-and T2-weighted MRI. A 4D developmental quantitative susceptibility mapping (QSM) atlas may facilitate the estimation of age-related iron changes in deep gray matter nuclei and myelin changes in white matter. To this end, group-wise co-registered QSM templates were generated over various age intervals from age 1-83 years old. Registration was achieved by combining both T1-weighted and QSM images. Based on the proposed template, we created an accurate deep gray matter nuclei parcellation map (DGM map). Notably, we segmented thalamus into 5 sub-regions, i.e. the anterior nuclei, the median nuclei, the lateral nuclei, the pulvinar and the internal medullary lamina. Furthermore, we built a "whole brain QSM parcellation map" by combining existing cortical parcellation and white-matter atlases with the proposed DGM map. Based on the proposed QSM atlas, the segmentation accuracy of iron-rich nuclei using QSM is significantly improved, especially for children and adolescent subjects. The age-related progression of magnetic susceptibility in each of the deep gray matter nuclei, the hippocampus, and the amygdala was estimated. Our automated atlas-based analysis provided a systematic confirmation of previous findings on susceptibility progression with age resulting from manual ROI drawings in deep gray matter nuclei. The susceptibility development in the hippocampus and the amygdala follow an iron accumulation model; while in the thalamus sub-regions, the susceptibility development exhibits a variety of trends. It is envisioned that the newly developed 4D QSM atlas will serve as a template for studying brain iron deposition and myelination/demyelination in both normal aging and various brain diseases.

Quantitative susceptibility mapping (QSM) as a means to monitor cerebral hematoma treatment.

BACKGROUND: Quantitative susceptibility mapping (QSM) offers a consistent hemorrhage volume measurement independent of imaging parameters. PURPOSE: To investigate the magnetic susceptibility of intracerebral hemorrhage (ICH) as a quantitative measurement for monitoring treatment in hematoma patients. STUDY TYPE: Prospective. POPULATION: Twenty-six patients with acute ICH were recruited and enrolled in treatment including surgery or medication (mannitol) for 1 week. FIELD STRENGTH/SEQUENCE: A 3D gradient echo sequence at 3.0T. ASSESSMENT: The hematoma volumes on computed tomography (CT) and QSM were calculated and used for correlation analysis. Magnetic susceptibility changes from pre- to posttreatment were calculated and compared to the National Institutes of Health stroke scale (NIHSS) measure of neurological deficit for each patient. STATISTICAL TESTS: Mean susceptibility values were calculated over each region of interest (ROI). A one-sample t-test was used to assess the changes of total volumes and mean magnetic susceptibility of ICH identified between pre- and posttreatment images (P < 0.05 was considered significant) and the Bland-Altman analysis with 95% limits of agreement (average difference, ±1.96 SD of the difference). Regression of volume measurements on QSM vs. CT and fitted linear regression of mean susceptibility vs. CT signal intensity for hematoma regions were conducted in all patients. RESULTS: Good correlation was found between hemorrhage volumes calculated from CT and QSM (CT volume = 0.94*QSM volume, r = 0.98). Comparison of QSM pre- and posttreatment showed that the mean ICH volume was reduced by a statistically insignificant amount from 5.74 cm3 to 5.45 cm3 (P = 0.21), while mean magnetic susceptibility was reduced significantly from 0.48 ppm to 0.38 ppm (P = 0.004). A significant positive association was found between changes in magnetic susceptibility values and NIHSS following hematoma treatment (P < 0.01). DATA CONCLUSIONS: QSM in hematoma assessment, as compared with CT, offers a comparably accurate volume measurement; however, susceptibility measurements may enable improved monitoring of ICH treatment compared to volume measurements alone. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;48:907-915.

Randomized Clinical Study Comparing Three Experimental Denture Adhesives and Fixodent® versus No Adhesive.

OBJECTIVES: Denture adhesives can improve function, retention, stability, and bite force in well-fitting dentures. This single-center, randomized, five-arm, examiner-blind, crossover clinical study aimed to compare three experimental adhesives ("Adhesive 1," "Adhesive 2," "Adhesive 3") with slightly different formulations and a commercially marketed "Positive control" with a "No Adhesive" arm using incisal bite force measurements over 12 hours in subjects with a moderately well- to well-fitting maxillary denture. METHODS: Institutional review and informed consent were obtained and qualified subjects were randomly assigned to a treatment sequence. Prior to adhesive application, subjects were asked to bite on a transducer with increasing force until their maxillary denture dislodged (bite force measurement). This procedure was repeated at 0.5, 1, 3, 6, 9, and 12 hours after adhesive application, with results recorded electronically. Treatment differences in the area over baseline (AOB) were analyzed using an ANCOVA model. RESULTS: A total of 48 subjects completed the study. All experimental formulations showed statistically significantly higher bite force measurements compared to the No Adhesive arm at all time points (p < 0.0001 for Adhesive 1 and Adhesive 2 at all times; p < 0.003 for Adhesive 3 at all times). While numerical values for bite force favored the Positive control for the duration of the study, there were no significant statistical differences at any time point between Adhesive 2 and the Positive control, and only over three and six hours compared to Adhesive 1. However, differences favored the Positive control compared to Adhesive 3 at all time points. CONCLUSIONS: All denture adhesives gave statistically significantly better bite force AOB in moderately well- to well-fitting dentures compared to no adhesive. All denture adhesives tested were generally well tolerated.

Exploring the origins of echo-time-dependent quantitative susceptibility mapping (QSM) measurements in healthy tissue and cerebral microbleeds.

Quantitative susceptibility mapping (QSM) is increasingly used to measure variation in tissue composition both in the brain and in other areas of the body in a range of disease pathologies. Although QSM measurements were originally believed to be independent of the echo time (TE) used in the gradient-recalled echo (GRE) acquisition from which they are derived; recent literature (Sood et al., 2016) has shown that these measurements can be highly TE-dependent in a number of brain regions. In this work we systematically investigate possible causes of this effect through analysis of apparent frequency and QSM measurements derived from data acquired at multiple TEs in vivo in healthy brain regions and in cerebral microbleeds (CMBs); QSM data acquired in a gadolinium-doped phantom; and in QSM data derived from idealized simulated phase data. Apparent frequency measurements in the optic radiations (OR) and central corpus callosum (CC) were compared to those predicted by a 3-pool white matter model, however the model failed to fully explain contrasting frequency profiles measured in the OR and CC. Our results show that TE-dependent QSM measurements can be caused by a failure of phase unwrapping algorithms in and around strong susceptibility sources such as CMBs; however, in healthy brain regions this behavior appears to result from intrinsic non-linear phase evolution in the MR signal. From these results we conclude that care must be taken when deriving frequency and QSM measurements in strong susceptibility sources due to the inherent limitations in phase unwrapping; and that while signal compartmentalization due to tissue microstructure and content is a plausible cause of TE-dependent frequency and QSM measurements in healthy brain regions, better sampling of the MR signal and more complex models of tissue are needed to fully exploit this relationship.

A Randomized Clinical Trial to Measure Mouth Moisturization and Dry Mouth Relief in Dry Mouth Subjects Using Dry Mouth Products.

OBJECTIVES: This study examined ratings of two subjective aspects (moisturization and dry mouth relief) that may be changed following the use of dry mouth relief products (an oral gel, an oral rinse, or a mouth spray), in comparison to water over a period of four hours following a single supervised use on two separate occasions. METHODS: This was a single-center, two site, randomized, examiner blind, four treatment arm, stratified (by dry mouth screening score at baseline), parallel group study in healthy subjects with a self-reported feeling of dry mouth. Prior to product use, subjects rated their current subjective perception of moisturization and dry mouth on an 11-point scale. Subjects then rated the two questions immediately after product use and 30, 60, 90, 120, and 240 minutes later. At the 240-minute time point, subjects also rated global efficacy questions regarding "overall" and "long-lasting" moisturization and dry mouth relief, and overall product opinion. Subjects then used their assigned products at home for three days and the procedures were repeated on Day 4. RESULTS: In total, 300 subjects were randomized to treatment. Compared with water, all test products showed statistically significantly greater improvements over baseline on both Day 1 and Day 4 at most time points, on the area under the curve from baseline for the moisturization and dryness questions, and after 240 minutes for the global efficacy and overall opinion assessments (all p < 0.05). There was a statistically significant difference between the pre-dosing assessments on Day 1 versus Day 4 (p < 0.001) for both efficacy questions. Products were generally well-tolerated. CONCLUSIONS: Three different types of dry mouth relief products were shown to provide significant relief of dry mouth and increased feelings of moisturization compared to water using subjective questionnaires.

A comparison of phase imaging and quantitative susceptibility mapping in the imaging of multiple sclerosis lesions at ultrahigh field.

OBJECTIVE: The aim of this study was to compare the use of high-resolution phase and QSM images acquired at ultra-high field in the investigation of multiple sclerosis (MS) lesions with peripheral rings, and to discuss their usefulness for drawing inferences about underlying tissue composition. MATERIALS AND METHODS: Thirty-nine Subjects were scanned at 7 T, using 3D T 2*-weighted and T 1-weighted sequences. Phase images were then unwrapped and filtered, and quantitative susceptibility maps were generated using a thresholded k-space division method. Lesions were compared visually and using a 1D profiling algorithm. RESULTS: Lesions displaying peripheral rings in the phase images were identified in 10 of the 39 subjects. Dipolar projections were apparent in the phase images outside of the extent of several of these lesions; however, QSM images showed peripheral rings without such projections. These projections appeared ring-like in a small number of phase images where no ring was observed in QSM. 1D profiles of six well-isolated example lesions showed that QSM contrast corresponds more closely to the magnitude images than phase contrast. CONCLUSIONS: Phase images contain dipolar projections, which confounds their use in the investigation of tissue composition in MS lesions. Quantitative susceptibility maps correct these projections, providing insight into the composition of MS lesions showing peripheral rings.

A randomized clinical trial in subjects with dry mouth evaluating subjective perceptions of an experimental oral gel, an oral rinse and a mouth spray compared to water.

PURPOSE: This multicenter, randomized, parallel group study analyzed the effectiveness of an experimental oral gel, a commercially available oral rinse and a commercially available mouth spray versus water alone at relieving self-reported symptoms of dry mouth over a 28-day home use treatment period. The effects of the study treatments on dry mouth-related quality of life (QoL) were also investigated. METHODS: Eligible subjects were stratified by dry mouth severity (mild, moderate or severe) and randomized to receive one of the study treatments. Prior to first use they completed a questionnaire designed to assess their baseline dry mouth-related QoL. Following first use and on Day 8 (2 hours post-treatment only) and Day 29, subjects completed the modified Product Performance and Attributes Questionnaire (PPAQ) I at 0.5, 1, 2 and 4 hours post-treatment. Subjects further assessed treatment performance using the PPAQ II questionnaire on Days 8 and 29 and the dry mouth-related QoL questionnaire on Day 29. RESULTS: In 396 randomized subjects almost all comparisons of responses to PPAQ I, including those for the primary endpoint (response to PPAQ I Question 1 'Relieving the discomfort of dry mouth' after 2 hours on Day 29), were statistically significant in favor of active treatment groups versus water (P < 0.05). All comparisons of responses to PPAQ II on Days 8 and 29 were statistically significant in favor of active treatments versus water (P < 0.05). Moreover, nearly all comparisons for dry mouth-related QoL scores on Day 29 were statistically significant in favor of the active treatments versus water. All the dry mouth management strategies in this trial were well tolerated.

Otalgia.

BACKGROUND: Otalgia is frequently seen in general practice. It can be broadly divided into primary otalgia, which includes the diseases occurring largely within the ear, or secondary otalgia, which is pain referred to the ear by travelling along cranial nerves that supply both the ear and referred region. The causes of secondary otalgia may require more extensive examination and investigation to define the aetiology. OBJECTIVE: The aims of this article are to outline the most common causes of otalgia seen in general practice, and provide a pragmatic approach to initial assessment and deciding when to refer for specialist review. DISCUSSION: The most common cause of primary otalgia is infection. Other causes require a greater index of suspicion. Specialist referral could be made if there are complications of primary otalgia or if a secondary cause needs to be excluded in a patient with a normal otology examination.

Evaluation of the Oral Tolerance of Three Fluoride Toothpaste Formulations in a Dry Mouth Population: Results from Two Randomized Studies.

OBJECTIVES: To evaluate the oral tolerance of three experimental toothpaste formulations containing sodium fluoride (NaF), compared with two marketed sodium monofluorophosphate (SMFP)-containing biotène® toothpastes, in a dry mouth population after 14 days (primary objective) and 7 days (secondary objective) of use. METHODS: Toothpastes were tested in two separate dual-site, examiner-blind, randomized, parallel group studies in subjects (35-84 years) with self-reported dry mouth. Oral soft tissue (OST) and oral hard tissue (OHT) examinations were performed at screening, followed by a 7- to 28-day wash-in period using a control toothpaste. Subjects were randomized to receive a NaF-containing toothpaste (Study 1: commercially available toothpaste Pronamel® for Children, n = 82; Study 2: experimental plaque biofilm-loosening formula [PBF] toothpaste, n = 79; or experimental Gentle Mint toothpaste, n = 78) or a reference toothpaste (Study 1: biotène® Fresh Mint Original toothpaste [previously marketed formulation], n = 82; Study 2: biotène® Gentle Mint Gel toothpaste [previously marketed formulation], n = 77) during the 14-day treatment phase. Subjects brushed their teeth twice daily for one timed minute with a ribbon of toothpaste to cover the head of the toothbrush provided. Subjects received further OST and OHT examinations at Day 1 and Day 15, and an additional OST examination at Day 8. Adverse events (AEs) and serious AEs (SAEs) were reported throughout the study. RESULTS: Study 1: At Day 15, 42 oral treatment-emergent AEs (TEAEs) were reported in 33 subjects, of which seven in five subjects (commercially available toothpaste Pronamel for Children: n = 2; control: n = 3) were considered to be treatment-related. One SAE (dyspnea) was reported in a participant who was randomized but withdrew from the study before receiving the allocated toothpaste. Study 2: At Day 15, 41 oral TEAEs were reported in 38 subjects, of which two in two subjects (experimental Gentle Mint toothpaste: n = 1; control: n = 1) were considered treatment-related, according to the investigator. No SAEs were reported. CONCLUSIONS: In both studies, the experimental and reference toothpastes were well tolerated after 7 and 14 days of use. The experimental NaF-containing toothpastes offer potential alternatives to individuals with dry mouth.

Single nucleotide polymorphism (SNP) variation of wolves (Canis lupus) in Southeast Alaska and comparison with wolves, dogs, and coyotes in North America.

There is considerable interest in the genetics of wolves (Canis lupus) because of their close relationship to domestic dogs (C. familiaris) and the need for informed conservation and management. This includes wolf populations in Southeast Alaska for which we determined genotypes of 305 wolves at 173662 single nucleotide polymorphism (SNP) loci. After removal of invariant and linked SNP, 123801 SNP were used to quantify genetic differentiation of wolves in Southeast Alaska and wolves, coyotes (C. latrans), and dogs from other areas in North America. There is differentiation of SNP allele frequencies between the species (wolves, coyotes, and dogs), although differentiation is relatively low between some wolf and coyote populations. There are varying levels of differentiation among populations of wolves, including low differentiation of wolves in interior Alaska, British Columbia, and the northern US Rocky Mountains. There is considerable differentiation of SNP allele frequencies of wolves in Southeast Alaska from wolves in other areas. However, wolves in Southeast Alaska are not a genetically homogeneous group and there are comparable levels of genetic differentiation among areas within Southeast Alaska and between Southeast Alaska and other geographic areas. SNP variation and other genetic data are discussed regarding taxonomy and management.

Molecular phylogeny and SNP variation of polar bears (Ursus maritimus), brown bears (U. arctos), and black bears (U. americanus) derived from genome sequences.

We assessed the relationships of polar bears (Ursus maritimus), brown bears (U. arctos), and black bears (U. americanus) with high throughput genomic sequencing data with an average coverage of 25× for each species. A total of 1.4 billion 100-bp paired-end reads were assembled using the polar bear and annotated giant panda (Ailuropoda melanoleuca) genome sequences as references. We identified 13.8 million single nucleotide polymorphisms (SNP) in the 3 species aligned to the polar bear genome. These data indicate that polar bears and brown bears share more SNP with each other than either does with black bears. Concatenation and coalescence-based analysis of consensus sequences of approximately 1 million base pairs of ultraconserved elements in the nuclear genome resulted in a phylogeny with black bears as the sister group to brown and polar bears, and all brown bears are in a separate clade from polar bears. Genotypes for 162 SNP loci of 336 bears from Alaska and Montana showed that the species are genetically differentiated and there is geographic population structure of brown and black bears but not polar bears.

Genetic variation and differentiation of bison (Bison bison) subspecies and cattle (Bos taurus) breeds and subspecies.

The genetic relationship of American plains bison (Bison bison bison) and wood bison (Bison bison athabascae) was quantified and compared with that among breeds and subspecies of cattle. Plains bison from 9 herds (N = 136), wood bison from 3 herds (N = 65), taurine cattle (Bos taurus taurus) from 14 breeds (N = 244), and indicine cattle (Bos taurus indicus) from 2 breeds (N = 53) were genotyped for 29 polymorphic microsatellite loci. Bayesian cluster analyses indicate 3 groups, 2 of which are plains bison and 1 of which is wood bison with some admixture, and genetic distances do not show plains bison and wood bison as distinct groups. Differentiation of wood bison and plains bison is also significantly less than that of cattle breeds and subspecies. These and other genetic data and historical interbreeding of bison do not support recognition of extant plains bison and wood bison as phylogenetically distinct subspecies.

Genetic relationships of extant brown bears (Ursus arctos) and polar bears (Ursus maritimus).

Polar bears (Ursus maritimus) and brown bears (Ursus arctos) are closely related species for which extensive mitochondrial and nuclear phylogenetic comparisons have been made. We used previously published genotype data for 8 microsatellite DNA loci from 930 brown bears in 19 populations and 473 polar bears in 16 populations to compare the population genetic relationships of extant populations of the species. Genetic distances (Nei standard distance = 1.157), the proportion of private alleles (52% of alleles are not shared by the species), and Bayesian cluster analysis are consistent with morphological and life-history characteristics that distinguish polar bears and brown bears as different species with little or no gene flow among extant populations.

Why near-miss events can decrease an individual's protective response to hurricanes.

Prior research shows that when people perceive the risk of some hazardous event to be low, they are unlikely to engage in mitigation activities for the potential hazard. We believe one factor that can lower inappropriately (from a normative perspective) people's perception of the risk of a hazard is information about prior near-miss events. A near-miss occurs when an event (such as a hurricane), which had some nontrivial probability of ending in disaster (loss of life, property damage), does not because good fortune intervenes. People appear to mistake such good fortune as an indicator of resiliency. In our first study, people with near-miss information were less likely to purchase flood insurance, and this was shown for both participants from the general population and individuals with specific interests in risk and natural disasters. In our second study, we consider a different mitigation decision, that is, to evacuate from a hurricane, and vary the level of statistical probability of hurricane damage. We still found a strong effect for near-miss information. Our research thus shows how people who have experienced a similar situation but escape damage because of chance will make decisions consistent with a perception that the situation is less risky than those without the past experience. We end by discussing the implications for risk communication.

Evaluation of the antiplaque efficacy of two cetylpyridinium chloride-containing mouthwashes.

OBJECTIVE: The purpose of this clinical study was to evaluate the efficacy in reducing dental plaque regrowth of two mouthwashes containing 0.075% cetylpyridinium chloride (CPC), one with 6% alcohol and one alcohol-free, as compared to a negative control mouthwash without CPC, using the Modified Gingival Margin Plaque Index (MGMPI). METHODS: The study was a double-blind, randomized, three-way crossover, controlled design. Following a washout period, subjects reported to the dental clinic where they were instructed to brush their teeth, used their assigned mouthwash, and were scored by the examining dentist for plaque using the MGMPI method. Subjects were instructed to refrain from all oral hygiene for the next 24 hours, except for rinsing with their assigned mouthwash 12 hours post-brushing. After this 24-hour period, subjects returned to the dental clinic and were once again scored for plaque. This sequence of washout followed by mouthwash use and plaque scoring was repeated until each subject had used all three mouthwashes. An ANOVA was conducted to assess between-group differences. RESULTS: The two test mouthwashes significantly reduced plaque regrowth over a 24-hour period (p < 0.05) as compared to the negative control mouthwash. The difference between the CPC-containing mouthwashes was not significant (p = 0.4868). CONCLUSION: Two mouthwashes containing 0.075% CPC, one with 6% alcohol and the other alcohol-free, were found to be safe and effective in reducing plaque accumulation when compared a negative control mouthwash without CPC. In short-term studies, the MGMPI appears useful for evaluating the antiplaque efficacy of mouthwash products.

Rapid whole-brain quantitative magnetization transfer imaging using 3D selective inversion recovery sequences.

Selective inversion recovery (SIR) is a quantitative magnetization transfer (qMT) method that provides estimates of parameters related to myelin content in white matter, namely the macromolecular pool-size-ratio (PSR) and the spin-lattice relaxation rate of the free pool (R1f), without the need for independent estimates of ∆B0, B1+, and T1. Although the feasibility of performing SIR in the human brain has been demonstrated, the scan times reported previously were too long for whole-brain applications. In this work, we combined optimized, short-TR acquisitions, SENSE/partial-Fourier accelerations, and efficient 3D readouts (turbo spin-echo, SIR-TSE; echo-planar imaging, SIR-EPI; and turbo field echo, SIR-TFE) to obtain whole-brain data in 18, 10, and 7 min for SIR-TSE, SIR-EPI, SIR-TFE, respectively. Based on numerical simulations, all schemes provided accurate parameter estimates in large, homogenous regions; however, the shorter SIR-TFE scans underestimated focal changes in smaller lesions due to blurring. Experimental studies in healthy subjects (n = 8) yielded parameters that were consistent with literature values and repeatable across scans (coefficient of variation: PSR = 2.2-6.4%, R1f = 0.6-1.4%) for all readouts. Overall, SIR-TFE parameters exhibited the lowest variability, while SIR-EPI parameters were adversely affected by susceptibility-related image distortions. In patients with relapsing remitting multiple sclerosis (n = 2), focal changes in SIR parameters were observed in lesions using all three readouts; however, contrast was reduced in smaller lesions for SIR-TFE, which was consistent with the numerical simulations. Together, these findings demonstrate that efficient, accurate, and repeatable whole-brain SIR can be performed using 3D TFE, EPI, or TSE readouts; however, the appropriate readout should be tailored to the application.