The immunosuppressive effect of the graft-versus-host reaction in mice

The graft-verus-host (GVH) reaction suppresses both cellular and humoral immune responses and is often lethal. Studies were performed to determine whether the GVH reaction itself could be altered by various cell treatments. GVH reactions were induced in adult CBA X A F1 mice by the injection of various doses of parental (A strain) lymphoid cells. Later the GVH animals received either an A strain thymus graft (PTG), CAF1 thymus graft (FITG) CAF1 bone marrow cells (SM)) CAF1 spleen graft (SG), F1TG and SM) F1TG and SG) or sham thymus graft (ST). At the higher cell doses it was found that F1TG by itself, or in combination with SM or SG shortened animal survival time. SM and SG treatment prolonged animal survival time. The results suggest that SM and SG protect F1 animals from the lethal effects of the GVH reaction, whereas F1TG increases the intensity of the GVH reaction

Advanced ultrasound screening for temporomandibular joint (TMJ) internal derangement

Purpose. To present an advanced ultrasound (US) technique and propose its use as a screening diagnostic tool for temporomandibular joint (TMJ) internal derangement. Materials and Methods. The technique is based on maintaining the US probe parallel to the articular disc, rather than traditional axial and coronal views, with the position described relative to a clock face. Validation was achieved by direct comparison with magnetic resonance imaging (MRI). A total of 61 patients, with age ranging from 13 to 67 years, were prescreened for TMJ pain and internal derangement, underwent US imaging for screening, and MRI evaluation for final diagnosis. Results. 29 of the 61 patients had disc pathology on MRI. US screening produced no false positive results and only 6 false negative results, corresponding to a sensitivity of 79% and specificity of 100%. Half of the false negative cases involved disc pathology with a medial component to the disc displacement. Conclusion. US is both a sensitive and a specific screening tool for TMJ dysfunction when used by an appropriately trained operator, with the exception of medially displaced discs. If TMJ assessment is found to be abnormal, the patient should be referred for MRI, and any patient scheduled for surgery must have the diagnosis confirmed by MRI. If a component of medial disc displacement is suspected, MRI should be performed despite a normal screening US

Drug-induced taste disorders in clinical practice and preclinical safety evaluation

More than 200 medications can induce taste disorders in patients. They not only reduce quality of life for those affected, but can lead to malnutrition, severe dehydration and difficulty in maintaining a therapeutic regimen. Nevertheless, the impact of drug candidates on taste is rarely evaluated in preclinical toxicology studies during the early stage of drug development. Moreover, knowledge about how to investigate these adverse effects is scarce in the toxicology field. Here, we discuss the clinical status of drug-induced taste disorders in patients, with the goal of providing toxicologists with a broad understanding of its prevalence, and how stressful and even dangerous it can be to affected patients. Because taste, smell, and oral trigeminal sensation are highly interdependent, we also address drug-induced changes in olfactory and oral somatosensory perceptions. We then review the biology of the gustatory system (including anatomy and histology), and the latest developments about how taste contributes to flavor perception. Finally, we feature recently optimized preclinical approaches to investigate drug-induced taste change in animal models, including morphological evaluation of taste buds and taste cells, gustatory nerve recording, and behavioral testing. Our goals are to raise awareness of drug-induced taste disorders among toxicologists, share an overview of new approaches and key studies that can be used to identify druginduced gustatory system toxicity early in the drug development process, and to stimulate further research at this emerging interface of chemosensory disorders with toxicology