Quantitative assessment of mast cells in recurrent aphthous ulcers (RAU)

Previous studies on the frequency of mast cells (MCs) in recurrent aphthous ulcers (RAU) have yielded conflicting results. Monoclonal antibodies specific for tryptase (AA1) and anti-IgE (polyclonal antibody) were used to identify density and distribution of MCs in an immunohistochemical study of RAU (n=15), induced oral traumatic ulcers (TUs) (n=9), and control clinically healthy oral mucosa (n=15). Results were quantified by means of a VIDAS image analyzer. In all sections studied, IgE-positive cells showed similar frequency and distribution to tryptase-positive MCs. In RAU lesions, numerous tryptase-positive MCs were found in the sub-epithelial lamina propria, but MC numbers in the epithelium were low and present only in some RAU biopsies. MCs were also more numerous in RAU-inflammatory infiltrates (118+/-31 cells/mm2) than those seen in TU-inflammatory infiltrates (75+/-18 cells/mm2, P<0.001). MC activation/degranulation, as judged by diffuse extracellular tryptase staining, was a common feature within RAU-inflammatory infiltrates and at RAU-inflammatory infiltrates-connective tissue interfaces, which were often associated with connective tissue disruption. MC counts in the RAU connective tissue, lateral to the inflammatory infiltrates, were significantly greater than in the connective tissue of TUs and of control biopsies (124+/-36 vs 73+/-13 vs 69+/-21 cells/mm2, respectively; P<0.001). Overall, MCs were significantly increased in aphthae (116+/-26 cells/mm2) compared with TU lesions (72+/-11 cells/mm2, P<0.001) and controls (71+/-16 cells/mm2, P<0.001). In conclusion, MC numbers are increased in a typical topographical pattern, and the local MCs show signs of activation/degranulation suggesting active involvement of this cell type in RAU pathogenesis.     

Taste and smell complaints in HIV-infected patients

OBJECTIVES: To define the scope of taste and smell (chemosensory) complaints amongst HIV-infected persons in the study population; to evaluate the clinical factors associated with chemosensory complaints; and to determine the impact of chemosensory complaints on quality of life. DESIGN: Cross-sectional survey. SETTING: Tertiary care university medical center clinic. PARTICIPANTS: A total of 207 HIV-infected patients. MAIN OUTCOME MEASURES: Chemosensory complaint score from taste and smell questionnaire and quality of life scores from the Medical Outcomes Study HIV Health Survey (MOS-HIV). RESULTS: A total of 144 patients (70%) reported chemosensory complaints, 91 (44%) reported both taste and smell complaints, 47 (23%) reported only taste complaints, and six (3%) reported only smell complaints. Many patients complained that drugs interfered with their sense of taste, or that medications tasted bad. Higher chemosensory complaint scores were associated with a greater number of medications taken, tobacco use, and hay fever. Patients with chemosensory complaints had significantly lower scores in all domains of the MOS-HIV than those without complaints. Quality of life as measured by the MOS-HIV was lower in patients with chemosensory complaints even after controlling for number of AIDS diagnoses, number of medications, CD4 cell count, and HIV-1 viral load. CONCLUSIONS: Chemosensory complaints were common in the patient population and were associated with a poor quality of life. Medications played an important role in chemosensory complaints. Measures to optimize taste and smell function may improve quality of life and medication adherence, and prevent complications such as inadequate oral intake, malnutrition, weight loss, and ultimately wasting.     

Partial activation of CD8+ T cells by a self-derived peptide

T cells are normally activated when the peptide for which they are specific is presented to them in the context of the appropriate major histocompatibility complex (MHC) (class I and Class II for CD8+ and CD4+ T cells, respectively). An increasing body of evidence indicates that structural homologues of the immunogenic peptide can partially activate or antagonize CD4+ T cells. CD8+ T cells may also be partially antagonized by such peptides, and self-derived peptides of this type may play a role in CD8+ T cell selection in the thymus. Activated CD8+ T cells lyse their targets by perforin-dependent granule exocytosis and by inducing apoptosis mediated by CD95 (also known as Fas or APO1) with its ligand (CD95L). Here we show that a clone of Kd-restricted CD8+ T cells specific for influenza haemagglutinin, which can also be activated in a crossreactive manner by a peptide derived from a myeloma tumour immunoglobulin heavy-chain variable region (IgVH) to kill by both routes, kills only by the CD95-CD95L pathway when stimulated by the corresponding germline IgVH peptide. As this germline IgVH peptide differs from the tumour peptide only at a single position buried in the MHC-binding groove, this indicates that CD95-CD95L-mediated killing can be triggered independently of the perforin-mediated pathway, and can be selectively affected by changes in MHC conformation.     

Measurement of intravariceal pressure by fine needle direct puncture in hepatitis B surface antigen-positive cirrhotic patients: the effect of vasopressin

A trp E fusion protein containing a C-terminal portion of the rat substance P receptor (SPR) was expressed in bacteria and used to produce an antibody. The antibody specifically reacted with SPR expressed in a mammalian cell line and rat striatum. Light and electron microscope analyses of the rat striatum revealed intense SPR-like immunoreactivity in neuronal somata and dendrites. These immunoreactive neurons constituted approximately 3% of the total population of striatal neurons; they were putative interneurons of large and medium-sized aspiny type.