Cancer stem cell phenotype relates to radio-chemotherapy outcome in locally advanced squamous cell head-neck cancer.

BACKGROUND: Cancer stem cells (CSCs) tend to repopulate malignant tumours during radiotherapy and, therefore, prolongation of the overall treatment time may result in radiotherapy failure. Thus, an estimate of the number of CSCs in tumour biopsies may prove most useful in predicting resistance to radiotherapy and a guide for development therapies aimed to eradicate a cancer cell population with effects on radiotherapy-related cancer regrowth. METHODS: The CSC population was investigated semi-quantitatively in 74 locally advanced squamous cell head-neck cancers (HNSCC) from an equal number of patients, treated with accelerated platinum-based radiotherapy. A standard immunohistochemical technique and the CSC markers CD44, CD24, Oct4, integrin-ß1 and aldehyde dehydrogenase isoform 1A1 (ALDHA1) was used, in parallel with the proliferation marker MIB-1. The results were correlated with the site of the tumour, the MIB-1 index, the tumour grade and stage, and prognosis. RESULTS: The expression of CD44, CD24 and Oct4 were significantly associated with the MIB-1 proliferation index. In addition, the CD44 was linked with the better differentiated HNSCC. The CD44, Oct4 and integrin-ß1 were all associated with poor prognosis but, in a multivariate analysis, the integrin-ß1 had an independent statistical significance in terms of local relapse, distant metastases and overall survival. Interestingly, ALDH1 was associated with favourable prognosis. CONCLUSION: CSC markers are linked with poor radiotherapy outcome in HNSCC, with integrin-ß1 being the strongest and independent prognostic factor. Targeting CSC molecules with monoclonal antibodies or pharmaceutical agents may prove important for the treatment of HNSCC.

Relative diagnostic importance of electronystagmography and magnetic resonance imaging in vestibular disorders.

OBJECTIVE: The aim of this study was to investigate the contribution of electronystagmography and magnetic resonance imaging to the aetiological diagnosis of vertigo and unsteadiness, in a population in which the history and clinical examination provide no conclusive diagnosis of the origin of the dysfunction (i.e. peripheral or central). PATIENTS AND METHODS: This retrospective study included 102 patients, who underwent full ENT clinical evaluation, history and neurotological assessment (including pure tone audiography, auditory brainstem response testing, electronystagmography and magnetic resonance imaging). RESULTS: Electronystagmography contributed to establishment of a diagnosis in 53/102 patients (52 per cent), whereas magnetic resonance imaging did the same in four of 102 patients (3.9 per cent). CONCLUSION: Electronystagmography remains the most useful examination for aetiological diagnosis of patients with vertigo and unsteadiness, since the actual number of patients with vertigo and unsteadiness of central origin is small (3.9 per cent), even in a population in which history and clinical examination may indicate an increased probability of central nervous system dysfunction.

The physiological basics of the olfactory neuro-epithelium.

All living organisms can detect and identify chemical substances in their environment. The olfactory epithelium is covered by a mucus layer which is essential for the function of the olfactory neurons that are directly connected to the brain through the cribriform plate. However, little is known about the composition of this mucus in humans and its significance for the diagnosis of olfactory disorders. The olfactory epithelium consists of four primary cell types, including the olfactory receptor cells essential for odour transduction. This review examines the anatomical, histological and physiological fundamentals of olfactory mucosa. Particular attention is paid to the biochemical environment of the olfactory mucosa that regulates both peri-receptor events and several protective functions.

The maxillary sinus and its endodontic implications: clinical study and review.

OBJECTIVES: Endodontic infections of posterior maxillary teeth sometimes spread to the maxillary sinus, generating severe complications. The aim of this study is to present the various problems encountered during endodontic treatment of these teeth. METHODS: The files of 125 cases of odontogenic chronic maxillary sinusitis were reviewed retrospectively. RESULTS: Chronic apical periodontitis was the cause in 99 cases and traumatising endodontic treatment in 26 cases. Foreign intra-sinusal bodies were occasionally seen as a consequence of different endodontic treatments of posterior maxillary teeth. CONCLUSIONS: A knowledge of dento-antral relationships is particularly important in the prevention of sinusal accidents and complications during various therapeutic manoeuvres, which should be performed according to and depending on the regional morphology.

Extended high-frequency audiometry in patients with acoustic trauma.

OBJECTIVES: The aim of this study was to examine extended high-frequency (EHF) hearing in patients with acoustic trauma. DESIGN: A prospective, case-control study in a group of soldiers with acoustic trauma caused by shooting practice during basic training. SETTING: Tertiary referral centre. PARTICIPANTS: A total of 39 young soldiers hospitalized for hearing loss and tinnitus following exposure to weapon impulse noise were studied. Conventional audiometry in the frequency range 0.25-8 kHz and EHF audiometry in the frequency range 9-20 kHz were performed, both on admittance and before discharge. Thirty healthy recruits of similar age and sex were used as controls. MAIN OUTCOME MEASURES: Pure-tone threshold changes documented by conventional and EHF audiometry. RESULTS: The most significant differences in pure-tone thresholds on initial testing were found in the frequency range 0.25-11.2 kHz, and especially in the 4-8 kHz region. Reduction in thresholds across most frequencies was observed after treatment, although recovery was partial in most cases. CONCLUSIONS: The EHF audiometry adds no significant additional information to conventional pure-tone audiometry in assessing and monitoring noise-induced hearing loss.

Effects of cigarette smoking on the antioxidant defence in young healthy male volunteers.

Cigarette smoking induces a significant oxidant effect related to variety of free radical-related diseases often affecting the upper respiratory tract, unless it is effectively compensated by the antioxidant barriers of the humans. In the present study, the evaluation of the antioxidant compensatory mechanisms, by estimating the antioxidant capacity of extracellular defence (saliva and plasma) and the intracellular resistance of peripheral lymphocytes to oxidative stress in young healthy smokers, was investigated. Twenty young healthy male smokers and 20 age-matched non-smokers with similar dietary profiles were enrolled in the study. Total saliva and plasma samples were collected from both groups, and total antioxidant capacity (TAC) and lag time were estimated. The latter was also repeated in smokers just after a cigarette smoking. Peripheral lymphocytes isolated from the subjects of both groups were also tested for their inherent DNA damage as well as for their ability to resist H2O2-induced DNA damage by using the comet assay. TAC of plasma was found significantly higher in smokers compared to non-smokers (p <0.004), whereas no difference was recorded in plasma lag time values. Lymphocytes of smokers manifested a significantly decreased oxidant resistance (increased DNA fragmentation) to H2O2, in comparison to non-smokers. Our results indicate that young smokers do not manifest different salivary antioxidant defence than non-smokers. They exhibit, however, a higher plasma antioxidant capacity, but a significantly reduced ability of blood lymphocytes, to resist to H2O2-induced DNA damage.

A comparative study of age and degree of facial nerve recovery in patients with Bell's palsy.

The purpose of this study was to investigate if there is any relationship between the age of a patient and the degree of facial nerve recovery in patients with Bell's palsy. Between 1987 and 1995 250 patients with peripheral idiopathic facial nerve palsy were examined at the ENT Clinic of the University of Ioannina. In this group 134 were male and 116 were female. The patients' ages ranged from 4 to 80 years and had an average of 47.7 years. The average age of the male patients was 46.5 years and that of the female patients was 49.1 years. In the overall group of 250 patients 129 presented with a paralysis of the right facial nerve and 121 on the left. There was no case of bilateral palsies. When comparing the age of the patients and the degree of recovery, measuring age was associated with a decrease in complete recovery. While the percentage of complete recovery between age 4 and 50 years varied from 83% to 74%, respectively, the percentage of complete recovery decreased to less than 54% at age 80. Our results show that the age of the patient is a very important factor for facial nerve recovery.

Inner ear involvement in rheumatoid arthritis: a prospective clinical study.

Sensorineural hearing loss in rheumatoid arthritis (RA) has been reported to be the result of the extra-articular manifestation of the disease (rheumatoid nodular vasculitis) or due to drug ototoxicity. In an attempt to investigate the presence of sensorineural hearing loss and the possible causes for it we investigated prospectively 45 RA patients (42 female; three male) with a mean age of 52.5 +/- 10.7 years and a mean disease duration of 8.5 +/- 7.3 years. All patients underwent a complete physical examination and audiological evaluation which included pure tone audiometry and impedance audiometry (tympanogram, static compliance, acoustic reflex, reflex decay, acoustic reflex latency test. We found a sensorineural hearing loss > 20 dB HL in 44.4 per cent (40/90) ears. In all cases the site of hearing loss was the cochlea and in most of them it was bilateral and symmetric (16 patients out of 45 had bilateral sensorineural hearing loss i.e. 35.5 per cent. There was no correlation between sensorineural hearing loss and age, sex, disease duration, articular and extra-articular manifestations and the presence of autoantibodies in our patients. In addition, no correlation was found between sensorineural hearing loss and drug therapy for one at least of the following drugs: NSAIDs, D-penicillamine, plaquenil and methotrexate. We noticed a prologation of acoustic reflex latency in five patients (10 per cent) which was found to be correlated with the temporomandibular joint involvement and the presence of rheumatoid factor (RF). We conclude that inner ear involvement in RA is expressed by: (1) mild symmetric, bilateral sensorineural hearing loss of cochlear type in 35.5 per cent of patients; (2) normal acoustic reflex thresholds; (3) nondecay; and (4) prologation of acoustic reflex latency which appeared in a small number of patients (10 per cent).

Treatment of childhood bacterial meningitis with ceftriaxone once daily: open, prospective, randomized, comparative study of short-course versus standard-length therapy.

Fifty-two children were included in this study to evaluate and compare short- versus standard-length ceftriaxone therapy for bacterial meningitis. The duration of the short-course regimens was 4, 6 and 7 days for Neisseria meningitidis, Hemophilus influenzae and Streptococcus pneumoniae, respectively. The standard-length regimens were twice as long. On the basis of a computer-generated randomization list, 26 children were assigned either to the short- or to the standard-treatment regimen. Ceftriaxone was given intravenously once daily in a dose of 60 mg/kg after an initial loading dose of 100 mg/kg. The population characteristics, the severity of disease and the cerebrospinal fluid (CSF) findings were similar in the two study groups at admission. Bacteriological and clinical response were comparable. There were no significant differences in the incidence of neurological complications, prolonged fever (greater than or equal to 10 days), persistent pleocytosis and side effects between the two groups. Hearing loss occurred in 3 patients in the standard-length group and in no patients in the short-course group. Diarrhea was the only side effect and occurred in 14% of the patients. The results of the study indicate that the short-duration regimen was adequate for the treatment of meningitis caused by the three major meningeal pathogens. However, the small number of patients do not justify the adoption of the short-course regimen for all children with meningitis. At present, prolongation of ceftriaxone therapy or discontinuation of the drug under strict clinical observation of the patient should be considered in some cases.