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New Findings r What is the central question of this study?Data on human carotid body (CB) function are limited. The aim of this study was therefore to investigate whether the human CB releases acetylcholine, ATP or cytokines during hypoxia. r What is the main finding and its importance?Using human CBs, we demonstrate hypoxia-induced acetylcholine and ATP release, suggesting that these neurotransmitters, as in several experimental animal models, play a role in hypoxic signalling also in the human carotid body. Moreover, the human CB releases cytokines upon hypoxia and expresses cytokine receptors as well as hypoxia-inducible factor proteins HIF-1α and HIF-2α in glomus cells, indicating their role in immune signalling and oxygen sensing, respectively, in accordance with previous animal data.Studies on experimental animals established that the carotid bodies are sensory organs for detecting arterial blood O 2 levels and that the ensuing chemosensory reflex is a major regulator of cardiorespiratory functions during hypoxia. However, little information is available on the human carotid body responses to hypoxia. The present study was performed on human carotid bodies obtained from surgical patients undergoing elective head and neck cancer surgery. Our results show that exposing carotid body slices to hypoxia for a period as brief as 5 min markedly facilitates the release of ACh and ATP. Furthermore, prolonged hypoxia for 1 h induces an increased release of interleukin (IL)-1β, IL-4, IL-6, IL-8 and IL-10. Immunohistochemical analysis revealed that type 1 cells of the human carotid body express an array of cytokine receptors as well as hypoxia-inducible factor-1α and hypoxia-inducible factor-2α. Taken together, these results demonstrate that ACh and ATP are released from the human carotid body in response to hypoxia, suggesting that these neurotransmitters, as in several experimental animal models, play a role in hypoxic signalling also in the human carotid body. The finding that the human carotid body releases cytokines in response to hypoxia adds to the growing body of information M.J.F. and L.I.E. contributed equally to this paper.

A local disturbance in the afferent nerves involved in the reflexogenic dilation of the upper airways (UAs) could contribute to the increased collapsibility seen in patients with obstructive sleep apnea (OSA). Laser Doppler perfusion monitoring, combined with electrical stimulation, is a method for investigating the afferent nerve regulation of the microcirculation. It was used in the mucosa of the soft palate in 35 patients with various degrees of UA obstruction and in 13 control subjects, all nonsmoking men. In a majority of snorers and patients with mild OSA, stimulation induced an exaggerated vasodilation, compared with controls. In contrast, in patients with severe OSA, the vasodilation was significantly reduced, compared with controls. These signs of disturbances in the microcirculation support the hypothesis of a local progressive afferent nerve lesion in heavy snorers with or without OSA.

In children with recurrent tonsillitis there may be persistent antigen deposition in tonsil tissue. even between exacerbations. If so, upregulation of immunocompetent cells should occur continuously, in contrast to tonsil tissue from children with tonsillar hypertrophy. The cytokine pattern was studied in cell suspensions prepared from tonsils obtained from 12 children undergoing tonsillectomy. The study group comprised 6 children with recurrent tonsillitis and 6 who had a history of tonsillar hypertrophy causing sleep apnea. Cytokine-producing cells (IL-1alpha, IL-1beta, TNFalpha, IL-6, IL-8, IL-2, IFNgamma, TNFbeta, IL-10 and IL-4) were characterized at the single-cell level by use of cytokine-specific monoclonal antibodies and indirect immunofluorescence technique. A constitutive production of IL-1alpha, IL-1beta, TNFalpha, and IL-8 was found in both groups (10-300/10(5) cells). However, the frequency of spontaneous IL-2, IFNgamma, TNFalpha, IL-6 and IL-10 was consistently low (10 +/- 10 cells) in both groups. Following restimulation by T-cell receptor ligation, using immobilized anti-CD3 mAb, with concentrations chosen so that it did not activate resting cells, increased frequencies of TNFalpha, IL-6, IL-8, IL-2, IFNgamma, IL-4 and 1L-10 synthesizing cells were induced in the recurrent tonsillitis group. Significantly higher incidences of IL-1beta, IL-6 and IL-2 producing cells were found in the recurrent tonsillitis group (60-200/10(5) cells, p <0.05). Microbiological evaluation in the tonsil tissue could not reveal tiny differences between the studied groups regarding bacterial or viral pathogens. However, this does not exclude persistent increased intracellular deposition of microbial antigens as a possible explanation for the elevated incidence of IL-1beta, TNF-alpha, IL-6, IL-8, IL-2, IFNgamma, IL-10 and IL-4 expressing cells noticed in patients with recurrent tonsillitis.

To provide retrospective, descriptive information on patients with cervical necrotizing fasciitis treated at a single center during the years 1998-2014, and to evaluate the outcome of a newly introduced treatment strategy. Retrospective analysis of clinical data obtained from medical records. Mortality, pre-morbidity, severity of illness, primary site of infection, type of bacteria, time parameters. The observed 3-month mortality was 6/59 (10 %). The most common initial foci of the infection were pharyngeal, dental or hypopharyngeal. The most common pathogen was Streptococcus milleri bacteria within the Streptococcus anginosus group (66 % of the cases). Using a combined treatment with early surgical debridement combined with hyperbaric oxygen treatment, it is possible to reduce the mortality rate among patients suffering from cervical necrotizing fasciitis, compared to the expected mortality rate and to previous historical reports. Data indicated that early onset of hyperbaric oxygen treatment may have a positive impact on survival rate, but no identifiable factor was found to prognosticate outcome.