Computerized Tool to Manage Dental Anxiety: A Randomized Clinical Trial.

Anxiety regarding dental and physical health is a common and potentially distressing problem, for both patients and health care providers. Anxiety has been identified as a barrier to regular dental visits and as an important target for enhancement of oral health-related quality of life. The study aimed to develop and evaluate a computerized cognitive-behavioral therapy dental anxiety intervention that could be easily implemented in dental health care settings. A cognitive-behavioral protocol based on psychoeducation, exposure to feared dental procedures, and cognitive restructuring was developed. A randomized controlled trial was conducted (N = 151) to test its efficacy. Consenting adult dental patients who met inclusion criteria (e.g., high dental anxiety) were randomized to 1 of 2 groups: immediate treatment (n = 74) or a wait-list control (n = 77). Analyses of covariance based on intention-to-treat analyses were used to compare the 2 groups on dental anxiety, fear, avoidance, and overall severity of dental phobia. Baseline scores on these outcomes were entered into the analyses as covariates. Groups were equivalent at baseline but differed at 1-mo follow-up. Both groups showed improvement in outcomes, but analyses of covariance demonstrated significant differences in dental anxiety, fear, avoidance, and overall severity of dental phobia in favor of immediate treatment at the follow-up assessment. Of the patients who met diagnostic criteria for phobia at baseline, fewer patients in the immediate treatment group continued to meet criteria for dental phobia at follow-up as compared with the wait-list group. A new computer-based tool seems to be efficacious in reducing dental anxiety and fear/avoidance of dental procedures. Examination of its effectiveness when administered in dental offices under less controlled conditions is warranted (ClinicalTrials.gov NCT02081365).

Fine needle aspiration of the thyroid. Use in an average health care facility.

Fine needle aspiration of the thyroid is suggested as an initial diagnostic procedure in the evaluation of thyroid nodules. Some proponents of the procedure, however, believe that fine needle aspiration should be restricted to centers in which each operator obtains at least 500 biopsy specimens annually. Reviewed were 155 biopsy specimens obtained over three and one-half years, and the sensitivity of fine needle aspiration was determined to be 100 percent, the specificity to be 47.4 percent, and the accuracy to be 73 percent. A review of the literature revealed the sensitivity in larger series to range between 92 and 98 percent, specificity to range between 52 and 99.5 percent, and accuracy to range between 56.1 and 91.3 percent. The surgical yield of carcinoma was 64 percent in patients evaluated with fine needle aspiration, whereas the yield was 26 percent in those who underwent surgery without fine needle aspiration. These results appear to justify the use of fine needle aspiration in the evaluation of nodular thyroid disease at average-sized health care centers.

A neuropsychological theory of multiple systems in category learning.

A neuropsychological theory is proposed that assumes category learning is a competition between separate verbal and implicit (i.e., procedural-learning-based) categorization systems. The theory assumes that the caudate nucleus is an important component of the implicit system and that the anterior cingulate and prefrontal cortices are critical to the verbal system. In addition to making predictions for normal human adults, the theory makes specific predictions for children, elderly people, and patients suffering from Parkinson's disease, Huntington's disease, major depression, amnesia, or lesions of the prefrontal cortex. Two separate formal descriptions of the theory are also provided. One describes trial-by-trial learning, and the other describes global dynamics. The theory is tested on published neuropsychological data and on category learning data with normal adults.

Reactivity and assay restriction profiles of monoclonal and polyclonal antibodies to acid phosphatases: a preliminary study.

The development of secure diagnostic immunoassays requires, among others, rigorous characterisation of potential antibody reagents. The reactivity profiles of seven antibodies (six monoclonal [MAb] and one polyclonal [PAb]) with putative specificity for tartrate-resistant acid phosphatase (TRAP) and/or osteoclasts were evaluated in enzyme-linked immunosorbent assay (ELISA) and/or immunocytochemistry. MAbs 2H1, 4E6 and 5Cl demonstrated assay restriction: exhibiting reactivity only in ELISA. The remaining three MAbs (G211D, G312G and V35B) and the PAb 8023 recognised recombinant TRAP (rTRAP) in ELISA and native acid phosphatases in selected tissues and cell lines. The latter were cytochemically assessed for both tartrate-sensitive acid phosphatase (TSAP) and TRAP. V35B showed reactivity against the monocytic leukaemia cell line U937 and guinea pig kidney tissue (both TSAP+ and TRAP+) and ECV304 (TSAP+) cells. Interestingly, the reactivity of MAb G211D co-localised with TRAP activity in the membrane of osteoclasts but also detected cytoplasmic components in U937 cells and human embryonic lung fibroblasts (TRAP+ and TRAP+). G211D exhibited immunoreactivity against placental trophoblasts (positive for total AP). Intriguingly, MAbs 2H1, 4E6, 5Cl and PAb 8023 cross-reacted with potato acid phosphatase in ELISA, suggesting reactivity to conformationally similar epitopes. Thus, some of these reagents could be used in the development of standardised diagnostic immunoassays or as drug-targeting agents for conditions in which the pathological process involves bone resorption, the MAbs G211D, 2H1, 4E6, 5Cl and PAb 8023 being useful in ELISA but not immunocytochemical detection of TRAP.

Suboptimality in human categorization and identification.

Categorization and identification decision processes were examined and compared in 4 separate experiments. In all tasks, the critical stimulus component was a line that varied across trials in length and orientation, and the optimal decision rules were always complex piecewise quadratic functions. Evidence was found that identification is mediated by separate explicit and implicit systems. In addition, a common type of suboptimality was found in both categorization and identification. In particular, observers apparently approximated the piecewise quadratic functions of the optimal decision rules with simpler piecewise linear functions. A computational model, which was motivated by a recent neuropsychological theory of category learning, successfully accounted for this suboptimal performance in both categorization and identification. The model assigns a key role to the striatum and assumes the observed suboptimality was largely due to massive convergence of visual cortical cells onto single striatal units.

On the nature of implicit categorization.

Current categorization models disagree about whether people make a priori assumptions about the structure of unfamiliar categories. Data from two experiments provided strong evidence that people do not make such assumptions. These results rule out prototype models and many decision bound models of categorization. We review previously published neuropsychological results that favor the assumption that category learning relies on a procedural-memory-based system, rather than on an instance-based system (as is assumed by exemplar models). On the basis of these results, a new category-learning model is proposed that makes no a priori assumptions about category structure and that relies on procedural learning and memory.

The effects of concurrent task interference on category learning: evidence for multiple category learning systems.

Participants learned simple and complex category structures under typical single-task conditions and when performing a simultaneous numerical Stroop task. In the simple categorization tasks, each set of contrasting categories was separated by a unidimensional explicit rule, whereas the complex tasks required integrating information from three stimulus dimensions and resulted in implicit rules that were difficult to verbalize. The concurrent Stroop task dramatically impaired learning of the simple explicit rules, but did not significantly delay learning of the complex implicit rules. These results support the hypothesis that category learning is mediated by multiple learning systems.

Sputum cytology within and across laboratories. A reliability study.

A total of 11 cytotechnologists at sites in Texas (TX1, TX2), California (CA) and Arkansas (AR) were assessed for agreement of six-category diagnoses of sputum cytology slides prepared by the method of Saccomanno. For three observers at TX1 there was more agreement within observers (27-60%) than across observers (13-50%). Within-1 category intraobserver agreement underwent a twofold to threefold increase, to 77-93%; within-2 category agreement was 90-100%. Interobserver within-1 category agreement was 47-92%; within-2 category agreement was 83-100%. Agreement was significantly greater than chance (using kappa) in 69% of all intraobserver and interobserver pairings. Intralaboratory agreement was 40% for CA and 40-57% for TX2. Among pairings of the four sites, the range of interlaboratory agreement was 13-60% over several occasions. The overall range of agreement with the TX1 standard was 17-50% over observers/occasions. Within certain categories, outside agreement with the TX1 standard was 53-90% for normal, 39-80% for squamous metaplasia, 68-84% for mild atypia, 80-100% for moderate atypia and 93-100% for severe atypia or carcinoma. We conclude that agreement is acceptable for extreme atypia, but more training or refinement of the guidelines may be needed, if justified, to better differentiate the lowest categories. Good agreement appears to be as likely for observers with many years of overall experience as for those with high exposure to the Saccomanno method. For potential statistical analyses, the scale should probably be condensed into three to four categories to reduce extraneous variability.

Confirmation of identities of propylene and ethylene glycols in anchovies by tandem mass spectrometry.

A gas chromatographic/tandem mass spectrometric (GC/MS/MS) method has been developed for confirming the identity of propylene and ethylene glycols added to bait fish for preservation. Bait fish are occasionally illegally diverted to human food use. The bait fish were extracted with methanol, the extract was centrifuged and filtered, and the filtrate was concentrated 10-fold and then analyzed by GC/MS/MS. The glycols were separated chromatographically without derivatization or preliminary cleanup. Isobutane positive ion chemical ionization was used to generate the protonated molecular ion species of each glycol. Product-ion MS/MS experiments were performed to obtain spectra to confirm the identities of propylene and ethylene glycols. The identities of these 2 compounds in anchovy extracts were successfully confirmed by this approach.

Generation and characterization of monoclonal antibodies to the neural crest.

The generation of monoclonal antibodies (MAbs) specific for quail neural crest may provide valuable tools for studying the differentiation of embryonic precursor cells. Unfortunately, relatively few antibodies are available because of the difficulty in obtaining sufficient cells for in vivo immunization strategies. We have overcome this problem by using intrasplenic immunization with formaldehyde-fixed cells harvested from neural crest cultures. In addition, booster injections of cultured whole-embryo cells were administered intraperitoneally. Following two fusions, a total of 18 hybridomas were generated with antibody reactivity to the cytoplasm of neural crest cells. Furthermore, 32 were reactive against both somite (a noncrest mesodermal control) and crest cultures, whilst 15 were not reactive. Out of those hybridomas reactive with neural crest, six designated 160D, 164D, OE, 12E, 120E and 124E were further characterized. Interestingly MAb supernatants OE, 12E, 120E, and 124E exhibited reactivity against some but not all neural crest cells suggesting that they might recognise subpopulations. Immunoglobulin isotyping of supernatants revealed that 4 (160D, 164D, OE, and 120E) were IgM and 2 (12E and 124E) were IgG(2b). On assessing their reactivity against human tissue sections, all six hybridoma supernatants cross-reacted with neuroendocrine cells within appendix, colon and rectum. These MAbs could provide novel reagents for the understanding of neural crest development.

Effects of exercise on dexterity.

As musicians occasionally report that their dextral facility is improved by recent exercise, it was hypothesized that manual dexterity would be influenced by a task requiring exertion. Before and after exertion on the Harvard Step Test, the experimental group's (n = 25) manual dexterity was tested on a grooved peg board. The control group's (n = 40) manual dexterity was measured before and after an inactive period. In both groups learning was significantly faster with the nondominant hand than with the dominant hand. Reasons why the hypothesis was not fully supported are discussed and suggestions for research noted.

Type VII collagen associated with the basement membrane of amniotic epithelium forms giant anchoring rivets which penetrate a massive lamina reticularis.

In human amnion a simple cuboidal epithelium and underlying fibroblast layer are separated by an almost acellular compact layer rich in collagen types I and III. This (>10 µm) layer, which may be a thick lamina reticularis, apparently presents an unusual set of conditions. Integration of the multilaminous tissue across it is apparently achieved by waisted structures which we have observed with the light microscope in frozen, paraffin-wax and semi-thin resin sections. We have also captured transmission and scanning electron micrographs of the structures. These structures which cross the compact layer we call "rivets". The composition of these "rivets" has been examined immunocytochemically and in three dimensions using the confocal laser scanning epi-fluorescence microscope. The rivets contain type VII collagen and an α6 integrin. They associate with type IV collagen containing structures (basement membrane lamina densa and spongy coils) and a special population of fibroblasts which may generate, maintain or anchor rivets to the underlying mesenchymal layer. Although type VII collagen is well known to anchor basal lamina to underlying mesodermal collagen fibres these "rivets" are an order of magnitude larger than any previously described type VII collagen containing anchoring structures. Intriguing possible functions of these features include nodes for growth of fibrous collagen sheets and sites of possible enzymatic degradation during regulated amnion weakening approaching term. If these sites are confirmed to be involved in amnion degradation and growth they may represent important targets for therapeutic agents that are designed to delay preterm premature rupture of the membranes a major cause of fetal morbidity and mortality.

Fine mapping of disease genes via haplotype clustering.

We propose an algorithm for analysing SNP-based population association studies, which is a development of that introduced by Molitor et al. [2003: Am J Hum Genet 73:1368-1384]. It uses clustering of haplotypes to overcome the major limitations of many current haplotype-based approaches. We define a between-haplotype score that is simple, yet appears to capture much of the information about evolutionary relatedness of the haplotypes in the vicinity of a (unobserved) putative causal locus. Haplotype clusters can then be defined via a putative ancestral haplotype and a cut-off distance. The number of an individual's two haplotypes that lie within the cluster predicts the individual's genotype at the causal locus. This predicted genotype can then be investigated for association with the phenotype of interest. We implement our approach within a Markov-chain Monte Carlo algorithm that, in effect, searches over locations and ancestral haplotypes to identify large, case-rich clusters. The algorithm successfully fine-maps a causal mutation in a test analysis using real data, and achieves almost 98% accuracy in predicting the genotype at the causal locus. A simulation study indicates that the new algorithm is substantially superior to alternative approaches, and it also allows us to identify situations in which multi-point approaches can substantially improve over single-SNP analyses. Our algorithm runs quickly and there is scope for extension to a wide range of disease models and genomic scales.

Attentional modulation in the detection of irrelevant deviance: a simultaneous ERP/fMRI study.

Little is known about the neural mechanisms that control attentional modulation of deviance detection in the auditory modality. In this study, we manipulated the difficulty of a primary task to test the relation between task difficulty and the detection of infrequent, task-irrelevant deviant (D) tones (1,300 Hz) presented among repetitive standard (S) tones (1,000 Hz). Simultaneous functional magnetic resonance imaging (fMRI)/event-related potentials (ERPs) were recorded from 21 subjects performing a two-alternative forced-choice duration discrimination task (short and long tones of equal probability). The duration of the short tone was always 50 msec. The duration of the long tone was 100 msec in the easy task and 60 msec in the difficult task. As expected, response accuracy decreased and response time (RT) increased in the difficult compared with the easy task. Performance was also poorer for D than for S tones, indicating distraction by task-irrelevant frequency information on trials involving D tones. In the difficult task, an amplitude increase was observed in the difference waves for N1 and P3a, ERP components associated with increased attention to deviant sounds. The mismatch negativity (MMN) response, associated with passive deviant detection, was larger in the easy task, demonstrating the susceptibility of this component to attentional manipulations. The fMRI contrast D > S in the difficult task revealed activation on the right superior temporal gyrus (STG) and extending ventrally into the superior temporal sulcus, suggesting this region's involvement in involuntary attention shifting toward unattended, infrequent sounds. Conversely, passive deviance detection, as reflected by the MMN, was associated with more dorsal activation on the STG. These results are consistent with the view that the dorsal STG region is responsive to mismatches between the memory trace of the standard and the incoming deviant sound, whereas the ventral STG region is activated by involuntary shifts of attention to task-irrelevant auditory features.

Characterization of anti-myosin monoclonal antibodies.

The characterization of monoclonal antibodies (MAbs) with regard to reactivity and specificity is important for the successful application as a molecular probe and/or diagnostic reagent. Furthermore, it is recognized that some monoclonal reagents perform well in some assay systems but not others. In this study, the reactivity profiles of two anti-myosin MAbs (H1 and DH2, raised against human cardiac myosin) were evaluated in enzyme-linked immunosorbent assay (ELISA), slot-blotting, and immunocytochemistry. Both antibodies performed well in slot-blotting against myosin heavy chain preparations from cardiac and skeletal muscle and from non-human sources. In general, MAb H1 demonstrated strong to moderate reactivity in all assay systems, whilst MAb DH2 faired poorly in ELISA. MAb H1 also showed reactivity to synthetic peptides of myosin, one of which possessed a motif (ERRDA, single amino acid code) that was found in other human and nonhuman myosin protein sequences that could explain its cross-reactive profile. Intriguingly, this motif was found on viral and other pathogenic agents associated with myocarditis. Hence, it is speculated that this region could give some credence to the mechanism of molecular mimicry associated with some cardiac diseases. Overall, MAb H1 may serve as a useful probe of myosin structure.

Fluorometric determination of histamine in tuna: development of method.

Tuna extracts are treated with an anion exchange resin to remove interfering materials, histamine is derivatized with o-phthaladehyde, and the fluorescence of the resulting compound is measured fluorometrically. Replicate analyses of acceptable and decomposed tuna packed in oil or water agreed within 1 mg at a level of 10 mg/100 g and within 12 mg at a level of 100 mg/100 g. Recoveries of histamine added to fish were greater than 90 and greater than 83% at levels of 10 and 100 mg/100 g, respectively. The new method is more rapid and specific and is simpler than previous methods because no liquid-liquid extractions or chromatographic separations of histamine are required. The sensitivity of the method allows quantitation of less than 10 mg histamine/100 g sample. The accuracy and precision of the fluorometric method are comparable to those of the official AOAC colorimetric method.

Plasma steroid concentrations in conscious and anesthetized rabbits.

The ovarian steroids, estrogen, androgen, and progestin, were measured in the peripheral plasma of adult female rabbits that were either conscious or anesthetized with sodium pentobarbital (nembutal) or halothane. Concentrations of estrogen, androgens, and progestin were determined before and at 10 and 45 min after systemic injection of either buffer or LH. In the controls androgen levels were significantly different between animals anesthetized with nembutal and halothane. However, the greatest treatment effect was noted in plasma progestin concentrations which were significantly elevated in halothane-anesthetized animals in comparison to the conscious and nembutal-anesthetized animals. Following LH, the androgen and progestin levels were significantly elevated over basal levels. Most likely the treatment effect observed in the controls was still present but was overridden by the increased release of steroids following gonadotrophin stimulation. This study suggests that halothane, in contrast to nembutal, does significantly elevate peripheral progestin and androgen levels.

PIP: Plasma steroid concentrations in conscious and anesthetized rabbits were measured to determine if any differences exist. The steroid responses between animals injected with buffer and luteinizing hormone (LH) were also measured because the action of gonadotropins, the release of steroids, and the action of anesthetics occur at the membrane level. Anesthesia was induced by either injecting 2.5 cc of nembutal or by inhalation of halothane in a close circuit. Animals were bled for 15-minute intervals before and at 10 and 45 minutes after the injection of buffer or LH. In the controls, androgen levels were significantly different between animals anesthetized with nembutal and halothane. However, plasma progestin concentrations were significantly elevated in halothane-anesthetized animals in comparison to the conscious and nembutal-anesthetized animals. After LH injection, androgen and progestin levels were significantly elevated over basal levels. It is concluded that halothane, in contrast to nembutal, significantly elevates peripheral progestin and androgen levels.

Monoclonal antibodies.

Monoclonal antibodies are essential tools for many molecular immunology investigations. In particular, when used in combination with techniques such as epitope mapping and molecular modelling, monoclonal antibodies enable the antigenic profiling and visualisation of macromolecular surfaces. In addition, monoclonal antibodies have become key components in a vast array of clinical laboratory diagnostic tests. Their wide application in detecting and identifying serum analytes, cell markers, and pathogenic agents has largely arisen through the exquisite specificity of these unique reagents. Furthermore, the continuous culture of hybridoma cells that produce these antibodies offers the potential of an unlimited supply of reagent. In essence, when compared with the rather limited supply of polyclonal antibody reagents, the feature of a continuous supply enables the standardisation of both the reagent and the assay technique. Clearly, polyclonal and monoclonal antibodies have their advantages and disadvantages in terms of generation, cost, and overall applications. Ultimately, monoclonal antibodies are only produced when necessary because their production is time consuming and frustrating, although greatly rewarding (at least most of the time!). This is especially apparent when a monoclonal antibody can be applied successfully in a routine pathology laboratory or can aid in the clinical diagnosis and treatment of patients. In this article, the generation and application of monoclonal antibodies are demystified to enable greater understanding and hopefully formulate novel ideas for clinicians and scientists alike.