Understanding topical fluoride hesitancy and refusal behaviors through the extended parallel process model and health belief model.

OBJECTIVES: Topical fluoride helps prevent dental caries. However, many caregivers are hesitant about topical fluoride for their children and may refuse it during clinic visits. In this qualitative study, we assessed the relevance of the extended parallel process model (EPPM) and health belief model (HBM) in caregivers' decision-making about topical fluoride. METHODS: We interviewed 56 fluoride-hesitant or fluoride-refusing caregivers using a semi-structured interview script that included questions based on select constructs from the EPPM (perceived severity, susceptibility, response efficacy) and HBM (perceived benefits and consequences). Two team members conducted a thematic analysis of the interview data. RESULTS: Most caregivers acknowledged the severity of cavities but did not believe their child was susceptible. Caregivers also understood the general benefits of fluoride in preventing tooth decay, but reported low response efficacy of fluoride for their children especially compared to the other ways of reducing caries risk like reducing sugar intake and toothbrushing. Many caregivers had concerns about topical fluoride, especially regarding safety, with the potential consequences of fluoride outweighing its benefits. CONCLUSION: Our findings were generally consistent with the EPPM and HBM, which appear to be relevant in understanding fluoride hesitancy behaviors. Additional research is needed on ways to improve provider communications about topical fluoride with caregivers.

Complement and Humoral Adaptive Immunity in the Human Choroid Plexus: Roles for Stromal Concretions, Basement Membranes, and Epithelium.

The choroid plexus (CP) provides a barrier to entry of toxic molecules from the blood into the brain and transports vital molecules into the cerebrospinal fluid. While a great deal is known about CP physiology, relatively little is known about its immunology. Here, we show immunohistochemical data that help define the role of the CP in innate and adaptive humoral immunity. The results show that complement, in the form of C1q, C3d, C9, or C9neo, is preferentially deposited in stromal concretions. In contrast, immunoglobulin (Ig) G (IgG) and IgA are more often found in CP epithelial cells, and IgM is found in either locale. C4d, IgD, and IgE are rarely, if ever, seen in the CP. In multiple sclerosis CP, basement membrane C9 or stromal IgA patterns were common but were not specific for the disease. These findings indicate that the CP may orchestrate the clearance of complement, particularly by deposition in its concretions, IgA and IgG preferentially via its epithelium, and IgM by either mechanism.

Diffusely abnormal white matter in multiple sclerosis: further histologic studies provide evidence for a primary lipid abnormality with neurodegeneration.

Although multiple sclerosis (MS) lesions have been studied extensively using histology and magnetic resonance imaging (MRI), little is known about diffusely abnormal white matter (DAWM). Diffusely abnormal white matter, regions with reduced mild MRI hyperintensity and ill-defined boundaries, show reduced myelin water fraction, and decreased Luxol fast blue staining of myelin phospholipids, with relative preservation of myelin basic protein and 2',3'-cyclic-nucleotide 3'-phosphohydrolase. Because DAWM may be important in MS disability and progression, further histologic characterization is warranted. The MRI data were collected on 14 formalin-fixed MS brain samples that were then stained for myelin phospholipids, myelin proteins, astrocytes and axons. Diffusely abnormal white matter showed reduced myelin water fraction (-30%, p < 0.05 for 13 samples). Myelin phospholipids showed the most dramatic and consistent histologic reductions in staining optical density (-29% Luxol fast blue and -24% Weil's, p < 0.05 for 13 and 14 samples,respectively) with lesser myelin protein involvement (-11% myelin-associated glycoprotein, -10% myelin basic protein, -8% myelin-oligodendrocyte glycoprotein, -7% proteolipid protein, -5% 2',3'-cyclic-nucleotide 3'-phosphohydrolase, p < 0.05 for 3, 3, 1, 2, and 3 samples, respectively). Axonal involvement was intermediate. Diffusely abnormal white matter lipid and protein reductions occurred independently. These findings suggest a primary lipid abnormality in DAWM that exceeds protein loss and is accompanied by axonal degeneration. These phenomena may be important in MS pathogenesis and disease progression, which is prominent in individuals with DAWM.

Pathological basis of diffusely abnormal white matter: insights from magnetic resonance imaging and histology.

BACKGROUND: The pathological basis of diffusely abnormal white matter (DAWM) in multiple sclerosis (MS) has not been elucidated in detail, but may be an important element in disability and clinical progression. METHODS: Fifty-three subjects with MS were examined with T1, multi-echo T2 and magnetization transfer (MT). Twenty-three samples of formalin-fixed MS brain tissue were examined with multi-echo T2 and subsequently stained for myelin phospholipids using luxol fast blue, for axons using Bielschowsky, immunohistochemically for the myelin proteins myelin basic protein (MBP) and 2',3'-cyclic nucleotide 3' phosphohydrolase (CNP) and for astrocytes using glial fibrillary acidic protein (GFAP). Regions of interest in DAWM were compared with normal appearing white matter. RESULTS: Fourteen of 53 subjects with MS in the in vivo study showed the presence of DAWM. Subjects with DAWM were found to have a significantly lower Expanded Disability Status Scale (EDSS) and shorter disease duration (DD) when compared with subjects without DAWM (EDSS: 1.5 versus 3.0, p = 0.031; DD: 5.4 versus 10.3 years, p = 0.045). DAWM in vivo had reduced myelin water and MT ratio, and increased T2 and water content. Histological analysis suggests DAWM, which shows a reduction of the myelin water fraction, is characterized by selective reduction of myelin phospholipids, but with a relative preservation of myelin proteins and axons. CONCLUSIONS: These findings suggest that the primary abnormality in DAWM is a reduction or perturbation of myelin phospholipids that correlates with a reduction of the myelin water fraction.

Thalamic stimulation in multiple sclerosis: evidence for a 'demyelinative thalamotomy'.

The mechanism of action of deep brain stimulation (DBS) in the alleviation of tremor in multiple sclerosis (MS) and other neurological disorders is unknown. Moreover, whether the trauma accompanying this surgery is responsible for the induction of new MS plaques is controversial. Here we report the first description of the post-mortem imaging and pathologic findings in the brain of a MS patient who underwent thalamic DBS for the treatment of MS-induced tremor. MR imaging of formalin-fixed brain slices was carried out at 1.5, 3 and 7 Tesla and correlated with the histopathology. There were numerous demyelinative plaques in the white mater, cortex and deep gray matter. There were no plaques along the DBS tract within the sections that sampled the deep hemispheric white matter. However, deep within the thalamus focal demyelination approximated the tract, particularly in the region corresponding to the electrical field. The findings in this single case raise the possibility that focal demyelination may be induced by the electrical field and this may be responsible for long-lasting alleviation of tremor in the absence of continued electrostimulation.

Myelin water imaging of multiple sclerosis at 7 T: correlations with histopathology.

Myelin water imaging (MWI) promises to be invaluable in understanding neurological diseases like MS. However, a limitation of MWI is signal to noise ratio. Recently, a number of investigators have performed MWI at field strengths higher than 1.5 T. Our goal was to determine if myelin water imaging at increased SNR, arising from the use of a small bore 7 T MR system with optimized coil geometry, enables the production of superior myelin water maps with increased spatial detail and enables better correlations with histology. Ten formalin-fixed MS brain samples underwent a 32-echo T(2) relaxation experiment which measured myelin water fraction (MWF) on a 7-T animal MRI scanner. MWF correlated strongly qualitatively and quantitatively with luxol fast blue staining for myelin [mean (range): R(2)=0.78 (0.56-0.95), p<0.0001]. The quality and detail of 7 T myelin water maps were far superior to that previously seen at 1.5 T, allowing for visualization of fine structures such as the normal prominent myelination of the deeper cortical layers, the alveus of the hippocampus and rings of preserved myelin in a concentric Balo's lesion. 7 T imaging will allow detailed assessment of myelin pathology to a degree not possible with lower field strengths.