Raman spectroscopy and surface-enhanced Raman spectroscopy (SERS) spectra of salivary glands carcinoma, tumor and healthy tissues and their homogenates analyzed by chemometry: Towards development of the novel tool for clinical diagnosis.

In this study, two approaches to salivary glands studies are presented: Raman imaging (RI) of tissue cross-section and surface-enhanced Raman spectroscopy (SERS) of tissue homogenates prepared according to elaborated protocol. Collected and analyzed data demonstrate the significant potential of SERS combined with multivariate analysis for distinguishing carcinoma or tumor from the normal salivary gland tissues as a rapid, label-free tool in cancer detection in oncological diagnostics. Raman imaging allows a detailed analysis of the cell wall's chemical composition; thus, the compound's distribution can be semi-quantitatively analyzed, while SERS of tissue homogenates allow for detailed analysis of all moieties forming these tissues. In this sense, SERS is more sensitive and reliable to study any changes in the area of infected tissues. Principal component analysis (PCA), as an unsupervised pattern recognition method, was used to identify the differences in the SERS salivary glands homogenates. The partial least squares-discriminant analysis (PLS-DA), the supervised pattern classification technique, was also used to strengthen further the computed model based on the latent variables in the SERS spectra. Moreover, the chemometric quantification of obtained data was analyzed using principal component regression (PCR) multivariate calibration. The presented data prove that the PCA algorithm allows for 91% in seven following components and the determination between healthy and tumor salivary gland homogenates. The PCR and PLS-DA methods predict 90% and 95% of the variance between the studied groups (in 6 components and 4 factors, respectively). Moreover, according to calculated RMSEC (RMSEP), R2C (R2P) values and correlation accuracy (based on the ROC curve), the PLS-DA model fits better for the studied data. Thus, SERS methods combined with PLS-DA analysis can be used to differentiate healthy, neoplastic, and mixed tissues as a competitive tool in relation to the commonly used method of histopathological staining of tumor tissue.

Are questionnaires reliable in diagnosing sleep-disordered breathing in university students?

OBJECTIVE: This study aimed to screen young adults for sleep-disordered breathing, and compare those with high and low risk for sleep-disordered breathing. METHODS: A survey based on the Berlin questionnaire was completed by 330 university students, and the results were used to divide them into sleep-disordered breathing positive and sleep-disordered breathing negative groups. A representative group was selected from each cohort (positive group, n = 16; negative group, n = 21), and assessed with sleep study, ENT examination, the Nose Obstruction Symptom Evaluation scale, and the Epworth Sleepiness Scale. RESULTS: Sleep-disordered breathing prevalence was 11.2 per cent in the questionnaire and 24 per cent according to the sleep study. The sleep-disordered breathing positive and negative groups significantly differed in terms of coexisting sleep-disordered breathing symptoms. There were no significant differences between the positive and negative groups with regard to sleep study parameters (apnoea/hypopnoea index, respiratory disturbance index, oxygen desaturation index, snoring intensity) and the Epworth Sleepiness Scale. CONCLUSION: Subjective and objective diagnostic tools revealed that sleep-disordered breathing is a common problem among young adults.

Increased severity of sleep-disordered breathing is associated with insomnia and excessive somnolence in primary school children.

OBJECTIVE: The aim of the study was to investigate the prevalence of difficulty with initiation or maintenance of sleep (DIMS) and excessive daytime sleepiness (EDS) in a general pediatric population, and to evaluate the relationship between these conditions and sleep-disordered breathing (SDB) symptom intensity. METHODS: This population-based cross-sectional study from 27 primary schools in a medium-sized city in Poland was based on use of a questionnaire regarding demographic data, symptoms of SDB, DIMS, and EDS. Data were collected between September and December 2014. In all, 2940 caregivers were recruited and were asked to fill-out questionnaires and written consent. RESULTS: A total of 68% of the questionnaires (n = 1987) were returned and analyzed. Habitual snoring (HS) was reported in 104 (5.3%) children. DIMS and EDS were seen in 137 children (6.9%) and 117 children (5.9%), respectively. The prevalence of DIMS increased from 3.5% in children who never snored to 28.6% in children who snored very often or always. Similarly, the prevalence of EDS was 2.7% in children who did not snore and increased to 19% in children who snored very often or always. No correlation was seen between increasing DIMS (r = 0.006, p > 0.05) or EDS (r = -0.031, p > 0.05) scores and body mass index. CONCLUSIONS: This study is the first to measure the symptoms of both DIMS and EDS in a general pediatric population and to assess the relationship between both DIMS and EDS and SDB in children. We found that children with more frequent snoring had a higher prevalence of DIMS as well as EDS; however, there was no correlation between body mass index and either DIMS or EDS symptom severity.

Gamma-aminobutyric acid concentrations in benign parotid tumours and unstimulated parotid saliva.

OBJECTIVE: Apart from its role as an inhibitory neurotransmitter, γ-aminobutyric acid is also thought to regulate various stages of cell proliferation and differentiation in the brain and periphery. The present study aimed to assess the levels of γ-aminobutyric acid and its biochemical precursor glutamic acid (glutamate) in benign parotid tumours and in unstimulated parotid saliva. METHOD: Unstimulated parotid saliva was collected bilaterally, using the swab method, in 20 patients with unilateral pleomorphic adenoma or Warthin's tumour. Samples of tumour and adjacent salivary tissue were collected during tumour resection. RESULTS: Concentrations of γ-aminobutyric acid and glutamate, but not aspartate, were significantly higher in the tumour tissue than in the non-tumour tissue. There was no significant difference in salivary concentrations of γ-aminobutyric acid, glutamate or aspartate, comparing the involved and non-involved side. CONCLUSION: The present results provide preliminary evidence that γ-aminobutyric acid may be involved in the growth of benign parotid tumours.

Post-tonsillectomy dysgeusia with weight loss: possible involvement of soft palate.

OBJECTIVE: To demonstrate the importance of detailed, multidisciplinary examination of patients with post-tonsillectomy taste distortions, and to show that post-tonsillectomy dysgeusia may originate in the caudal part of the soft palate. CASE REPORT: We describe a 29-year-old man who suffered from severe post-tonsillectomy dysgeusia and phantogeusia with secondary weight loss and depression-like symptomatology. The patient had normal electrogustometric thresholds and sensitivity to touch on the posterior tongue. In contrast, elevated taste threshold and reduced sensitivity to touch was found on the caudal part of the soft palate (the palatoglossal arches). More marked elevation of electrogustometric threshold and insensitivity to touch on the right palatoglossal arch correlated with post-operative haemorrhage from the right tonsillar fossa. Psychiatric examination excluded major depression, eating disorders and drug abuse. CONCLUSIONS: Dysgeusia constitutes a rare but significant complication of tonsillectomy. Damage to the lingual branch of the glossopharyngeal nerve innervating the posterior tongue is thought to be a major cause of this complication. However, damage to the tonsillar branches of the glossopharyngeal nerve and the soft palate should also be considered as a cause of post-tonsillectomy dysgeusia. Further studies are needed to assess whether post-operative haemorrhage could indicate heightened risk of dysgeusia.

Kinetic and pharmacological properties of Ca(2+) currents in postganglionic sympathetic neurones projecting to muscular and cutaneous effectors.

Voltage-gated Ca(2+) channels are expressed in neurones and greatly influence neuronal activity by activating Ca(2+)-dependent K(+) channels. The whole cell patch-clamp technique was used to compare the kinetic and pharmacological properties of voltage-dependent Ca(2+) currents in two groups of sympathetic neurones identified by the fluorescent tracer Fast Blue: putative muscular sympathetic neurones (MSN) and putative cutaneous sympathetic neurones (CSN). The tracer was injected into the muscular part of the diaphragm (to mark MSN) and into the skin of the ear (to mark CSN). The capacitance of MSN (23.0 pF) was larger than the capacitance of CSN (12.6 pF). The maximum current in MSN (1.3 nA) was also larger than in CSN (0.93 nA). However, the current density was larger in CSN (77. 3 pA/pF) than in MSN (57.7 pA/pF) and the current activation rate was faster in CSN (0.27 nA/ms) than in MSN (0.19 nA/ms). V(1/2) and slope factors of activation and inactivation were not significantly different for MSN and CSN. The majority of Ca(2+) current was available for activation in both categories of neurones at resting membrane potential. Ca(2+) currents in MSN and CSN were blocked by nifedipine (7.0 and 3.6%, respectively), omega-Agatoxin-IVA (23.0 and 25.6%, respectively) and omega-conotoxin-GVIA (67.0 and 65.1%, respectively). We found that CSN are twice as small, have higher Ca(2+) current density and their Ca(2+) activation rate is faster in comparison to MSN. Such properties may lead to faster rise of Ca(2+) concentration in the cytoplasm of the CSN comparing to MSN and more effectively dampen their activity due to more effective activation of Ca(2+)-dependent K(+) current. Both kinds of neurones express high proportion of N and P/Q Ca(2+) current.

Stellate neurones innervating the rat heart express N, L and P/Q calcium channels.

The aim of the study was to investigate the kinetic properties and identify the subtypes of Ca2+ currents in the cardiac postganglionic sympathetic neurones of rats. Neurones were labelled with a fluorescent tracer--Fast-Blue, injected into the pericardial cavity. Voltage-dependent Ca2+ currents were recorded from dispersed stellate ganglion cells that showed Fast Blue labelling. Only high threshold voltage-dependent Ca2+ currents were found in the somata of cardiac sympathetic neurones. Their maximum amplitude, mean cell capacitance and current density were respectively: 0.67 nA, 19.3 pF and 36.4 pA/pF (n = 21). The maximum Ca2+ conductance was 51.3 nS (n = 14). Half activation voltage equalled +11.0 mV and the slope factor for conductance 11.1 (n = 14). As tested with a 10 s pre-pulse, the Ca2+ current began to inactivate at -80 mV. Half inactivation voltage and slope factor for steady-state inactivation were -36.6 mV and 14.1 (n = 9), respectively. Saturating concentration of L channel blocker (nifedipine), N channel blocker (omega-conotoxin-GVIA), P/Q channel blocker (omega-Agatoxin-IVA) and N/P/Q channel blocker (omega-conotoxin-MVIIC) reduced the total Ca2+ current by 26.8% (n = 7), 57.1% (n = 12), 25.9% (n = 6) and 69.4% (n = 6), respectively. These results show that the somata of cardiac postganglionic cardiac sympathetic neurones contain significant populations of N, L and P/Q high threshold Ca2+ channels.