A New Era of Morphological Investigations: Reviewing Methods for Comparative Anatomical Studies.

The increased use of imaging technology in biological research has drastically altered morphological studies in recent decades and allowed for the preservation of important collection specimens alongside detailed visualization of bony and soft-tissue structures. Despite the benefits associated with these newer imaging techniques, there remains a need for more "traditional" methods of morphological examination in many comparative studies. In this paper, we describe the costs and benefits of the various methods of visualizing, examining, and comparing morphological structures. There are significant differences not only in the costs associated with these different methods (monetary, time, equipment, and software), but also in the degree to which specimens are destroyed. We argue not for any one particular method over another in morphological studies, but instead suggest a combination of methods is useful not only for breadth of visualization, but also for the financial and time constraints often imposed on early-career research scientists.

Determinants of non-adherence to anti-TB treatment in high income, low TB incidence settings: a scoping review.

BACKGROUND: Improving adherence to anti-TB treatment is a public health priority in high-income, low incidence (HILI) regions. We conducted a scoping review to identify reported determinants of non-adherence in HILI settings.METHODS: Key terms related to TB, treatment and adherence were used to search MEDLINE, EMBASE, Web of Science, PsycINFO and CINAHL in June 2019. Quantitative studies examining determinants (demographic, clinical, health systems or psychosocial) of non-adherence to anti-TB treatment in HILI settings were included.RESULTS: From 10,801 results, we identified 24 relevant studies from 10 countries. Definitions and methods of assessing adherence were highly variable, as were documented levels of non-adherence (0.9-89%). Demographic factors were assessed in all studies and clinical factors were frequently assessed (23/24). Determinants commonly associated with non-adherence were homelessness, incarceration, and alcohol or drug misuse. Health system (8/24) and psychosocial factors (6/24) were less commonly evaluated.CONCLUSION: Our review identified some key factors associated with non-adherence to anti-TB treatment in HILI settings. Modifiable determinants such as psychosocial factors are under-evidenced and should be further explored, as these may be better targeted by adherence support. There is an urgent need to standardise definitions and measurement of adherence to more accurately identify the strongest determinants.

Micro-computed tomography: an alternative method for shark ageing.

Micro-computed tomography (microCT) produced 3D reconstructions of shark Carcharhinus brevipinna vertebrae that could be virtually sectioned along any desired plane, and upon which growth bands were readily visible. When compared to manual sectioning, it proved to be a valid and repeatable means of ageing and offers several distinct advantages over other ageing methods.

Validation of quantitative magnetic resonance for the determination of body composition of mice.

OBJECTIVE: The aim of this study was to assess the precision and accuracy of a quantitative magnetic resonance (QMR) instrument for measuring body composition in live, non-anesthetized mice. METHODS: Forty-eight mice of varying strains, ages and body weights (15.3 to 50.2g) were scanned three times each in the QMR instrument. Animals were killed and chemical carcass analysis performed for comparison. Precision was assessed as the coefficient of variation (CV) for the triplicate scans and accuracy was determined by comparing the first QMR data with the chemical analysis. Prediction equations were generated by linear regression analysis and used in a cross-validation study in which 26 mice were scanned once each, killed, and chemical carcass analysis performed. RESULTS: The mean CV was 1.58% for fat mass (FM) and 0.78% for lean-tissue mass (LTM). QMR significantly (P<0.01) overestimated FM (7.76±5.93 vs. 6.03±5.17g) and underestimated LTM (20.73±6.19 vs. 22.48±6.75g) when compared with chemical carcass analysis. A strong relationship between QMR and chemical data (r(2)=0.99 and r(2)=0.97 for fat and LTM respectively; P<0.0001) allowed for the generation of correction equations that were applied to QMR data in the cross-validation study. There was no significant difference between data predicted from QMR and chemical carcass data for FM and LTM (P=0.15 and 0.10 respectively). CONCLUSION: The QMR instrument showed excellent precision and data was highly correlated with chemical carcass analysis. This combined with QMR's speed for whole animal analysis (95 seconds) make it a highly feasible and useful method for the determination of body composition in live, non-anesthetized mice.

Acoustic analysis in asthmatics and the influence of inhaled corticosteroid therapy.

The impact of sustained inhaled corticosteroid (ICS) therapy on the larynx and pharynx was assessed using a prospective, cross-sectional, and investigator-blinded study conducted at the University Hospital Aintree, Liverpool, UK. Forty-six adults recruited from two local general practices and from general ENT clinics at our University hospital were investigated for the study. Patients were allocated to three groups according to ICS use. Laryngeal effects were measured by correlating the results of a vocal performance questionnaire, a respiratory symptom questionnaire, and measurements obtained by computerized speech analysis. Sustained vowels and connected speech were analyzed in normal and asthmatic subjects. Acoustic analysis was correlated with cellular markers of inflammation after biopsy. Regular ICS users had significantly more pharyngeal inflammation and throat discomfort (P<0.0001). Vocal performance was also worse in this group (P<0.0001). They were more likely to have hoarseness, weakness of voice, aphonia, sore throat, throat irritation, and cough (P<0.0001). All these variables were directly related to one another (P<0.0001). Multiple linear regression analysis showed that jitter was a good objective measure of hoarseness (P<0.05). Regular ICS users were significantly more likely to have abnormal jitter, shimmer, and closed-phase quotient scores (P<0.0001). There was no difference between the groups in the observed parameters of inflammation (P>0.01). A higher pharyngitis score did not correlate with any of the histological markers of inflammation (P>0.01). Local side effects are more common in asthmatics that use ICS regularly. Measures of laryngeal function are significantly worse in regular ICS users. However, histological markers and oropharyngeal redness are not reliable measures of inflammation.

Prospective, randomized cross-over trial to assess the ability of a dry-powder inhaler to reverse the local side effects of pressurized metered-dose inhalers.

OBJECTIVES: To determine whether a corticosteroid dry-powder inhaler could reverse the pharyngeal and laryngeal side effects produced by a corticosteroid pressurised metered-dose inhaler. DESIGN: Prospective, randomized, controlled, cross-over, evaluator-blinded study. SETTING: University Hospital Aintree, Liverpool, United Kingdom. PATIENTS: Thirty-seven adults recruited over a 12-month period from Ear, Nose and Throat clinics at our University hospital. Patients were randomized into three groups using a computer-generated random number list and sealed opaque envelopes. MAIN OUTCOME MEASURES: Scores were achieved on respiratory symptom and vocal performance questionnaires. Acoustic analysis was performed followed by a standardized biopsy of the posterior pharyngeal wall. Histological markers of inflammation were correlated with pharyngitis. The data were tested for normality using the Kalmogorov-Smirnov test. The Kruskal-Wallis analysis of variance was used to investigate differences between medians and ranges. The data were further investigated for correlations using the Spearman test. Discriminant analysis was used to examine the effect of the three groups on each variable. RESULTS: Discomfort scores (median and range) were significantly lower after dry-powder inhaler use than with either a spacer or water gargle (p < 0.01). These worsened after restoring pressurized metered-dose inhaler therapy. The reduction in pharyngitis in each of the three groups was not significant. Vocal performance scores improved with dry-powder inhaler use. Jitter, shimmer, and closed-phase quotient scores improved with dry-powder inhaler use (p < 0.01). Shimmer scores deteriorated once the pressurized metered-dose inhaler was restored (p < 0.01). There was no significant difference between the groups in most observed parameters of inflammation (p > 0.01). CONCLUSION: A dry-powder inhaler may alleviate the local side effects produced by a pressurized metered-dose inhaler. Laryngeal dysfunction appears to be particularly responsive to the absence of propellant. More observational and randomized controlled trials are necessary to examine existing inhalers and specifically, how and why they cause local side effects.

Expression of cell cycle associated proteins influences radiocurability of T2N0 squamous cell carcinoma of the larynx.

Cell cycle modulators are important in carcinogenesis and may be of prognostic and therapeutic relevance. This study has examined the influence of the proliferation index (Ki-67) and immunocytochemical expression of epidermal growth factor receptor (EGFR), cyclin D1, and retinoblastoma protein on recurrence rates at the primary site in 50 patients with T2N0 laryngeal carcinomas treated with radical irradiation. Pre-treatment biopsies were retrieved and sections scored for the four immunocytochemical markers. Statistical analysis for association, interaction and survival was performed. Five cases showed loss of expression of Rb protein. The median Ki-67 index was 50%, the median cyclin D1 index 21% and the median EGFR index 47% of cells. EGFR and cyclin D1 expression were positively correlated and, whilst local recurrence tended to occur with a Ki-67 labelling index of <50%, this was not statistically significant. When interactions were examined using Multiple Logistic Regression it was found that there was a direct relationship between EGFR and cyclin D1 expression. If the EGFR index was >20% and the cyclin D1 index >10%, then the odds ratio in favour of a primary site recurrence was very high (5.32 +/-0.41). This study demonstrates that the relationship between EGFR index and cyclin D1 index has a very strong association with primary site recurrence for T2 N0 laryngeal carcinomas treated by irradiation.

Prevalence of pharyngeal and laryngeal complications in adult asthmatics using inhaled corticosteroids.

OBJECTIVES: To investigate the prevalence in adults of pharyngeal and laryngeal symptoms associated with the use of inhaled corticosteroids. DESIGN: Prospective, observational and based on a structured, specifically designed postal questionnaire. SETTING: University Hospital Aintree, Liverpool, UK. PARTICIPANTS: The questionnaire was distributed to 190 patients on the basis of current inhaled corticosteroid use. Recruitment was from the databases of two local general practices. Individuals were classified as mild, moderate or severe asthmatics, using the guidelines of the British Thoracic Society. MAIN OUTCOME MEASURES: Demographic data, including smoking history, were recorded. The number, type, strength, dosing regime and duration of individual inhaler use were recorded. Specific pharyngeal and laryngeal side effects were enquired about. Co-morbidities and preventive measures were also recorded. Results were analysed using univariate and multivariate statistical tests. RESULTS: There was a 75.8 per cent response rate (144/190 questionnaires); 63 (43.8 per cent) of respondents were male and 81 (56.2 per cent) were female. The majority of our patients were either mild or moderate asthmatics. Longer use of an inhaled corticosteroid predisposed to weak voice (p = 0.0016), hoarseness (p = 0.0001) and throat irritation (p = 0.008). Hoarseness, throat irritation, sore throat and cough were observed much more frequently than anticipated. Severe asthmatics were more likely to use a spacer device compliantly (p = 0.0487; odds ratio 1.53). Side effects were more prevalent as asthma severity worsened (p = 0.0049; odds ratio 1.87). CONCLUSIONS: Inhaled corticosteroids cause sore throats, throat irritation, hoarseness and cough. Further research in this area is required in order to elucidate the mechanism of inflammation. Only then can effective preventive measures be introduced and implemented.

The inflammation produced by corticosteroid inhalers in the pharynx in asthmatics.

OBJECTIVES: To investigate inflammation of the pharyngeal mucosa caused by inhaled corticosteroids. DESIGN: Prospective, cross-sectional, single-blinded study. SETTING: University Hospital Aintree, Liverpool, UK. PATIENTS: Fifty adults were recruited from two local general practices and from general ENT clinics at our University hospital. Patients were allocated to one of four groups according to use of inhaled corticosteroids and the presence of adverse local side effects. MAIN OUTCOME MEASURES: Scores achieved on a respiratory symptom questionnaire. Histological markers of inflammation and their correlation with pharyngitis. Statistical modelling included univariate and multivariate analyses, which included multiple linear and logistic regression, and discriminant analysis. RESULTS: The regular use of inhaled corticosteroids predisposed subjects to hoarseness, weakness of voice, sore throat and throat irritation (P < 0.0001). Pharyngitis was significantly different between the groups (P < 0.0001). Furthermore, those not using an inhaled corticosteroid regularly had little or no clinically apparent pharyngitis, whereas those using an inhaled corticosteroid regularly had significantly higher pharyngitis scores (P = 0.0204). Similarly, weakness of voice (P = 0.0234), hoarseness (P < 0.001) and sore throat (P < 0.001) were also more common in those patients that used an inhaled corticosteroid on a regular basis. To our surprise, however, cellular markers of inflammation did not corroborate the appearances of clinical examination. We found that the five most important discriminators, between those that were using inhaled corticosteroid therapy regularly and those that were not, to be intra-epithelial inflammatory cells (scdf -1.2939); age (scdf 0.8389); use of a spacer device (scdf 0.5456); sore throat (scdf 0.4230) and throat irritation (scdf 0.4015). The groups were significantly different (P < 0.0001). The statistical model used, classified 68% of the cases correctly into their respective groups. CONCLUSIONS: Inhaled corticosteroids predispose to pharyngitis and an inflammatory infiltrate. However, the clinical diagnosis of pharyngitis does not correlate well with cellular inflammatory infiltrate and is therefore, not a reliable measure of underlying inflammation. We advocate caution in the use of pharyngeal erythema as a measure of underlying inflammation.

Life extension of self-healing polymers with rapidly growing fatigue cracks.

Self-healing polymers, based on microencapsulated dicyclopentadiene and Grubbs' catalyst embedded in the polymer matrix, are capable of responding to propagating fatigue cracks by autonomic processes that lead to higher endurance limits and life extension, or even the complete arrest of the crack growth. The amount of fatigue-life extension depends on the relative magnitude of the mechanical kinetics of crack propagation and the chemical kinetics of healing. As the healing kinetics are accelerated, greater fatigue life extension is achieved. The use of wax-protected, recrystallized Grubbs' catalyst leads to a fourfold increase in the rate of polymerization of bulk dicyclopentadiene and extends the fatigue life of a polymer specimen over 30 times longer than a comparable non-healing specimen. The fatigue life of polymers under extremely fast fatigue crack growth can be extended through the incorporation of periodic rest periods, effectively training the self-healing polymeric material to achieve higher endurance limits.

Airway dimensions measured from micro-computed tomography and high-resolution computed tomography.

Volume averaging results in both over- and underestimation of airway dimensions when they are measured by high-resolution computed tomography (HRCT). The current authors calibrated computerised measurements of airway dimensions from HRCT against a novel three-dimensional micro-computed tomography (CT) standard, which has a 50-fold greater resolution, as well as against traditional morphometry. Inflation-fixed porcine lung cubes were scanned by HRCT and micro-CT. A total of 59 lumen area (Ai), 30 wall area (A(aw)) and 11 lumen volume (Vi) measurements were made. Ai was measured from the cut surface of 11 airways by morphometry. Airways in scanned images were matched using branching points. After calibration, the errors of Ai, A(aw) and Vi HRCT measurements were determined. The current authors found a systematic, size-dependent underestimation of Ai and overestimation of A(aw) from HRCT measurements. This was used to calibrate an HRCT measurement algorithm. The 95% limits of agreement of subsequent measurements were +/-3.2 mm2 for Ai, +/-4.3 mm2 for A(aw), and +/-11.2 mm3 for Vi with no systematic error. Morphometric measurements agreed with micro-CT (+/-2.5 mm2) without systematic error. In conclusion, micro-computed tomography image data from inflation-fixed airways can be used as calibration standards for three-dimensional lumen volume measurements from high-resolution computed tomography, while morphometry is acceptable for two-dimensional measurements. The image dataset could be used to validate other developmental three-dimensional segmentation algorithms.

Passive smoking, allergic rhinitis and nasal obstruction in children.

Allergic rhinitis is a common cause of nasal obstruction in childhood. This prospective study looked at the effect of passive smoking on nasal obstruction in children with and without allergic rhinitis. Eighty-one children took part. Each child was asked to score his or her degree of nasal obstruction on a visual analogue scale. Exposure to passive smoking was determined subjectively using a parental questionnaire, and objectively by measuring the urinary cotinine/creatinine ratio. Results were tabulated using Microsoft Excel and analysed with SPSS statistical software. Nasal obstruction was significantly worse in children with a positive history of allergic rhinitis (p < 0.05). There was also a trend towards a higher nasal obstruction score in children without allergic rhinitis exposed to passive smoking compared to those who were not so exposed. As would be expected, nasal obstruction is worse in children with allergic rhinitis than in those without. Passive smoking tends to increase the symptom of nasal obstruction in children without allergic rhinitis.

How we do it: a series of 114 primary pharyngeal space neoplasms.

Primary parapharyngeal space tumours are exceedingly rare. We present a series of 114 parapharyngeal space tumours, the second largest in the literature. The most frequent benign tumours were pleomorphic adenoma (34) and paraganglioma (33); the commonest malignancies were of salivary gland origin (12). The 5- and 10-year survival for benign tumours was 100%. The 5- and 10-year survival for malignancies was 93% and 57% respectively. The importance of long-term follow-up is evidently crucial.

Matrix metalloproteinases and their inhibitors in non-neoplastic otorhinolaryngological disease.

Matrix metalloproteinases (MMPs) are a family of zinc and calcium-dependent endopeptidases that play a key role in extracellular matrix (ECM) degradation. MMPs are known to be important in normal remodelling processes. Overexpression and activation of MMPs or an imbalance of active MMPs and tissue inhibitors of metalloproteinases (TIMPs) has been linked with a number of specific disease states associated with the breakdown and remodelling of the extracellular matrix. MMPs and TIMPs play a role in the development and progression of conditions such as acute and chronic otitis media, nasal polyposis and Sjogren's disease of salivary glands. Their role in allergic rhinitis has not been proven although they do appear to have a role in asthma, a condition closely linked to rhinitis. The use of a broad spectrum MMP inhibitor has been shown to alter the outcome of acute otitis media and otitis media with effusion. Therapeutic strategies with anti-MMP molecules are currently being developed and may play a role in modulating the course of non-neoplastic otorhinolaryngological disease in the future.

Root resorption and its association with alterations in physical properties, mineral contents and resorption craters in human premolars following application of light and heavy controlled orthodontic forces.

OBJECTIVES: To study the effect of different orthodontic force levels on cementum, investigating from the point of view of its physical properties, alterations in the mineral components, type and location of the resorption craters and the exploration in 3D of space. DESIGN: In vivo human premolars subjected to heavy and light forces were employed for this study. After a period of movement they were analyzed for hardness and elasticity. Also, the mineral composition measuring Ca, P and F of the cementum root surface was investigated. A new method for volumetric analysis of resorption craters was developed. RESULTS: There were no significant differences for hardness and elastic modulus between the light and heavy force groups and no significant effects for different tooth positions. Significant inter-individual variation in the Ca, P and F concentrations was noted. Force-related data showed that mean volume of the resorption crater in light-force group was 3.49-fold greater than the control group, and the heavy-force group 11.59-fold more than control group. The heavy force group had 3.31-fold greater total resorption volume then light force group. Buccal cervical and lingual apical regions demonstrated significantly more resorption craters than the other regions. The 2D measurements were strongly correlated to 3D measurements. CONCLUSION: The application of light and heavy forces did not show any statistically significant differences in hardness and elastic modulus when compared with untreated teeth. The inconsistent increase or decrease of Ca, P and F contents between control and experimental teeth at sites of compression and tension were difficult to explain. There was more resorption by volume in the heavy force group as compared with the light group and controls. Our data also suggested that the high-pressure zones might be more susceptible to resorption after 28 days of force application.

The role and efficacy of non-linear models in decision making and prognostication.

In few types of cancer, genomic abnormalities have been linked to the phenotype and carcinogenesis with a degree of precision. For most cancers, however, this is not the case and the literature provides no clear indication of any logical process. The main difficulties are the great redundancy within the genome and proteome, the vast number of interconnections and the vast number of feedback loops. Such complicated systems can be modelled, but will require highly sophisticated analysis using computational mathematics techniques. Neural networks have been in common use in medical research for the past 20 years. They have been used for classification and for prediction of hazard or failure but are still not widely used for explanation. The binary output can be modified by, for example, adding a Bayesian function to the output stage so that survival probabilities can be given. We looked at the application of probabilistic neural networks in providing prognosis in two types of cancer; laryngeal carcinoma which has a relatively short hazard time and a medium survival rate and ocular melanoma with longer hazard time and higher survival rate. We compared their performance with the more traditional methods and studied their limitations and boundaries.