Sniff-Like Patterned Input Results in Long-Term Plasticity at the Rat Olfactory Bulb Mitral and Tufted Cell to Granule Cell Synapse.

During odor sensing the activity of principal neurons of the mammalian olfactory bulb, the mitral and tufted cells (MTCs), occurs in repetitive bursts that are synchronized to respiration, reminiscent of hippocampal theta-gamma coupling. Axonless granule cells (GCs) mediate self- and lateral inhibitory interactions between the excitatory MTCs via reciprocal dendrodendritic synapses. We have explored long-term plasticity at this synapse by using a theta burst stimulation (TBS) protocol and variations thereof. GCs were excited via glomerular stimulation in acute brain slices. We find that TBS induces exclusively long-term depression in the majority of experiments, whereas single bursts ("single-sniff paradigm") can elicit both long-term potentiation and depression. Statistical analysis predicts that the mechanism underlying this bidirectional plasticity involves the proportional addition or removal of presynaptic release sites. Gamma stimulation with the same number of APs as in TBS was less efficient in inducing plasticity. Both TBS- and "single-sniff paradigm"-induced plasticity depend on NMDA receptor activation. Since the onset of plasticity is very rapid and requires little extra activity, we propose that these forms of plasticity might play a role already during an ongoing search for odor sources. Our results imply that components of both short-term and long-term olfactory memory may be encoded at this synapse.

Measles mimicking HIV seroconversion syndrome: a case report.

INTRODUCTION: Measles is on the rise in the United Kingdom and must be considered in the differential diagnosis of any patient presenting with fever and rash. As a highly infectious disease, identified patients must be isolated in the hospital setting. CASE PRESENTATION: A 28-year-old Polish woman presented ill to the accident and emergency department of a district general hospital. She had painful genital ulceration, oral soreness, fever, and a facial rash. She became hypoxic within 24 hours of presentation and began to tire, thus requiring noninvasive ventilation. Her respiratory symptoms were out of proportion to the findings of her chest radiograph, which remained virtually normal. Human immunodeficiency virus seroconversion syndrome complicated by Pneumocystis carinii pneumonia was high among the differential diagnoses. She was given cotrimoxazole, high-dose steroids, broad spectrum antibiotics, and anti fungal cover.Human immunodeficiency virus polymerase chain reaction came back as negative and her symptoms resolved within 10 days of presentation. She was taken off all treatment and discharged home feeling well. Serological measles was confirmed as part of a viral screen, but its clinical suspicion was low. CONCLUSION: The presentation of measles in this patient was unique and atypical. With its incidence rising in the United Kingdom, measles must be increasingly considered as a differential diagnosis in patients presenting with fever and rash.

A comparison of the attitudes and beliefs of professional rugby players from one club and parents of children playing rugby at an adjacent amateur club to the wearing of mouthguards.

OBJECTIVE: To assess the knowledge that professional rugby players have with regard to the benefits of wearing an oral mouthguard and the importance that they give to wearing the appliance during play, then to compare these views with those of the parents of children who are beginning to play the sport. DESIGN: Questionnaires and covering letters were sent to the parents of children who played rugby at Malton & Norton Rugby Union Football Club (RUFC), which has teams for all age groups from under 7-8 years to adult. Similar questionnaires were sent to the first team squad of Leeds Tykes, a Zurich Premiership rugby union club. The questionnaires asked a series of questions on the use of mouthguards and knowledge of their importance in the prevention of injuries. RESULTS: The overall response rate was 76%. Seventy-four of the 100 questionnaires sent to the parents and 25 of the 30 sent to the professional players were completed and returned. Both the professional rugby players and parents felt that mouthguards were essential when playing rugby. The professionals seemed to have a much greater understanding of the benefits that mouthguards provided. Although parents agreed that children should begin to wear mouthguards as soon as possible, very few actually did. The barriers to providing mouth protection were mainly financial combined with the difficulties of taking the child to the dentist. CONCLUSIONS: If the results from this small study are representative of the current situation, with regard to the wearing of mouthguards by professional players and children, it appears that there is a need for all those involved to ensure that rugby-playing children wear mouthguards. Rugby clubs could consider the appointment of honorary dental advisers and devise systems to ensure that cost is not a factor in preventing children from wearing mouthguards.

Talon cusps presenting in a child with Alagille's syndrome--a case report.

Talon cusp is a rare dental anomaly often associated with systemic conditions such as Rubenstein-Taybi Syndrome, Ellis-van Crevald Syndrome and Incontentia pigmenti achromians. It has not been previously reported as occurring in Alagille Syndrome. Early diagnosis of talon cusps is crucial for the correct management and avoidance of complications. This case highlights the need for careful dental examination when treating children with syndromes, as new phenotypes that can have an effect on the dentition.