Role of 5-HT1A and 5-HT3 receptors in serotonergic activation of sensory neurons in relation to itch and pain behavior in the rat

Serotonin (5-hydroxytryptamine, 5-HT) released by platelets, mast cells, and immunocytes is a potent inflammatory mediator which modulates pain and itch sensing in the peripheral nervous system. The serotonergic receptors expressed by primary afferent neurons involved in these sensory functions are not fully identified and appear to be to a large extent species dependent. Moreover, the mechanisms through which 5-HT receptor activation is coupled to changes in neuronal excitability have not been completely revealed. Using a combination of in vitro (calcium and voltage imaging and patch-clamp) and in vivo behavioral methods, we used both male and female Wistar rats to provide evidence for the involvement of two 5-HT receptor subtypes, 5-HT1A and 5-HT3, in mediating the sustained and transient effects, respectively, of 5-HT on rat primary afferent neurons involved in pain and itch processing. In addition, our results are consistent with a model in which sustained serotonergic responses triggered via the 5-HT1A receptor are due to closure of background potassium channels, followed by membrane depolarization and action potentials, during which the activation of voltage-gated calcium channels leads to calcium entry. Our results may provide a better understanding of mammalian serotonergic itch signaling.     

Immediate replacement of a maxillary central incisor associated with severe facial bone loss: use of Bio-Oss collagen--case report

The loss and replacement of anterior maxillary teeth pose several challenges. Treatment must successfully address immediate tooth replacement, esthetics, patient comfort, and psychologic acceptance. The purpose of this case report is to present a prosthetic and surgical technique for immediate tooth replacement following extraction in an area of severe localized bone loss. Combined full- and partial-thickness flaps associated with the use of Bio-Oss collagen grafting material and a Bio-Gide membrane were used for alveolar ridge reconstruction. To improve the final esthetic result, a connective tissue graft was used to increase ridge volume and papillary height.     

Prevalence and risk indicators for periodontal attachment loss in a population of older community-dwelling blacks and whites

The extent and severity of periodontal attachment loss are described for a random sample of 690 dentate community-dwelling adults, aged 65 or over, residing in five counties in North Carolina. In addition, risk indicators for serious levels of loss of attachment and pocket depth in this population are presented. Pocket depths and recession were measured on all teeth by trained examines during household visits. Blacks had an average of 78% of their sites with attachment loss and the average level of loss in those sites was approximately 4 mm, as compared to 65% and 3.1 min for whites. Because the extent and severity scores in this population were much higher than in younger groups, a serious condition in this group was defined as having 4+ sites of loss of attachment of 5+ mm with one or more of those sites having a pocket of 4+ mm. Bivariate analyses identified a large number of explanatory variables that were associated with increased likelihood of having the more serious periodontal condition. The logistic regression model for blacks includes the following important explanatory variables and associated odds ratios: use to tobacco (2.9), colony counts of B. gingivalis greater than 2% (2.4) and B. intermedius greater than 2% (1.9), last visit to the dentist greater than 3 years (2.3), and gums bleeding in the last 2 weeks (3.9). The model for whites indicated that tobacco use (6.2), presence of B. gingivalis (2.4) and the combined variable of having not been to the dentist in the last 3 years and having a high BANA score (16.8) were important explanatory variables.(ABSTRACT TRUNCATED AT 250 WORDS)     

Improving youth question-asking and provider education during pediatric asthma visits

Objective

We conducted a pragmatic randomized controlled trial to test the effectiveness of an asthma question prompt list with video intervention to increase youth question-asking and provider education during visits.

Trichinella infection and clinical disease

Trichinellosis is caused by ingestion of insufficiently cooked meat contaminated with infective larvae of <it>Trichinella</it> species. The clinical course is highly variable, ranging from no apparent infection to severe and even fatal disease. We report two illustrative cases of trichinellosis. Returning to Denmark a few days after having eaten roasted pork in the Republic of Serbia, a female patient suffered from severe vomiting, epigastric pain, diarrhoea, and later myalgia, generalized oedema, and prostration. A biopsy showed heavy infestation with <it>Trichinella spiralis</it>, 2000 larvae/g of muscle. Life-threatening cardiopulmonary, renal and central nervous system complications developed. The patient recovered after several months. Her husband, who also ate the pork, did not have clinical symptoms, but an increased eosinophil count and a single larva in a muscle biopsy confirmed infection. The epidemiology, clinical manifestations, diagnosis, treatment and prevention of trichinellosis are reviewed.      

Iatrogenic Pseudoaneurysm of the Middle Meningeal Artery after External Ventricular Drain Placement

External ventricular drain (EVD) placement is often a routine but lifesaving neurosurgical procedure performed throughout the world. Misadventures involving the procedure are well documented throughout the literature. However, we present a unique case of middle meningeal artery pseudoaneurysm formation after EVD placement not before described and provide a review of the literature.