Effect of taste and smell on secretion rate of salivary IgA in elderly and young persons

Two experiments were performed to determine the effect of taste and odor stimuli on secretion rate of salivary IgA in young and elderly individuals. In Experiment 1, three stimuli were applied to the tongue: 1) "flavor" drops (60% sugar, 5% cocoa powder, and 0.1 % Irish cream odor); 2) sugar (60%); and 3) water. In Experiment 2, four different foods (chicken broth, onion soup, corn, and carrots) were tested with and without monosodium glutamate (MSG). The stimuli in both experiments were delivered three times in a one hour period: t=0, t=30 minutes, t=60 minutes. The results of Experiment 1 indicated that application of sugar (taste alone) and flavor (taste and odor combined) to the tongue induced significantly higher secretion rates of sIgA than the application of water in both elderly and young subjects. In addition, flavor application produced significantly higher secretion rates of sIgA than sugar application alone. Secretion rates of sIgA in young persons were significantly higher than those in elderly persons. In Experiment 2, the increase in secretion rate of sIgA at 30 and 60 minutes for each food with MSG was greater than the same food without MSG for the elderly subjects. The increases in secretion rates of sIgA were produced by elevated salivary flow (Experiments 1 and 2) as well as increased absolute concentrations of sIgA (Experiment 1). The elevation of absolute concentrations of sIgA by chemosensory stimuli may involve neural-immune connections. The improvements in salivary flow and secretory immunity by repeated taste and smell stimulation found here have clinical potential for treatment of immune deficiencies and dry mouth which frequently occur in elderly individuals.     

Delineation of brain tumor extent with [11C]L-methionine positron emission tomography: local comparison with stereotactic histopathology.

PURPOSE: Methyl-[11C]L-methionine ([11C]MET) positron emission tomography (PET) in brain tumors reflects amino acid transport and has been shown to be more sensitive than magnetic resonance imaging in stereotactic biopsy planning. It remains unclear whether the increased [11C]MET uptake is limited to solid tumor tissue or even detects infiltrating tumor parts. EXPERIMENTAL DESIGN: In 30 patients, a primary or recurrent brain tumor was suspected on magnetic resonance imaging. Patients were investigated with [11C]MET-PET before stereotactic biopsy. The biopsy trajectories were plotted into the [11C]MET-PET images with a newly designed C-based software program. The exact local [11C]MET uptake was determined within rectangular regions of interest of 4 mm in width and length aligned with the biopsy specimen. Individual histologic specimens were rated for the presence of solid tumor tissue, infiltration area, and nontumorous tissue changes. RESULTS: Receiver operating characteristics analysis demonstrated a sensitivity of 87% and specificity of 89% for the detection of tumor tissue at a threshold of 1.3-fold [11C]MET uptake relative to normal brain tissue. At this threshold, only 13 of 100 tumor positive specimen were false negative mainly in grade 2 astrocytoma. In grade 2 astrocytoma, mean [11C]MET uptake in the infiltration area was significantly higher than in solid tumor tissue (P < 0.003). CONCLUSIONS: [11C]MET-PET detects solid parts of brain tumors, as well as the infiltration area at high sensitivity and specificity. High [11C]MET uptake in infiltrating tumor of astrocytoma WHO grade 2 reflects high activity in this tumor compartment. Molecular imaging, with [11C]MET, will guide improved management of patients with brain tumors.     

Vibrations produced during erbium:yttrium–aluminum–garnet laser irradiation

The purpose of this study was to evaluate vibrations induced by an erbium:yttrium–aluminum–garnet (Er:YAG) laser in the non-contact mode and compare the vibrations with different pulse durations and energy parameters. The experiment was conducted on an extracted tooth built up in silicone impression material. The vibrations were measured by piezoelectric accelerometer for a super-short pulse (SSP), a very short pulse (VSP), and a short pulse (SP) at a frequency of 5 Hz for 1 s. For VSP and SP, the energy parameters tested were 200 mJ, 300 mJ, and 400 mJ. Measurements were performed 15 times for each individual irradiation energy level. The highest values of vibrations were measured for SP (0.160 ± 0.04 m/s²), and the lowest were measured for VSP mode at the energy parameter 200 mJ (0.05 ± 0.02 m/s²). There was a statistically significant (P < 0.01) difference between the various laser pulse modes (SSP, VSP, SP) at different energy parameters. At energy levels of 300 mJ and 400 mJ, the least amount of vibration during cavity preparations with the non-contact Er:YAG laser was produced by SSP mode.     

Oral cadmium exposure during rat pregnancy: assessment of transplacental micronutrient transport and steroidogenesis at term

Diet is the main source of cadmium (Cd) exposure. Gastrointestinal absorption increases during pregnancy. Cadmium accumulated in the placenta may interfere with nutrient transport to the foetus. Data on the potential of Cd to act as a steroid disruptor of pregnancy are limited. We evaluated the effects of oral Cd exposure during pregnancy on placental function in micronutrient transfer to the foetus and steroidogenesis in Wistar rats (regular 4‐day cyclers) that mated with unexposed males. Pregnant rats were randomly assigned to a Cd group exposed orally to 50 mg Cd l^–1 (CdCl₂xH₂O dissolved in demineralized water), ≈7.5 mg Cd kg^–1 a day, during 20 days of gestation and control (supplied with demineralized water). Non‐pregnant rats were treated under the same experimental conditions. On day 20, all of the rats were killed and samples were taken for element analyses (by electrothermal atomic absorption spectrometry). Progesterone and testosterone were measured in serum and placenta‐derived samples (by immunoenzymometric assay and/or enzyme‐linked immunosorbent assay). In the exposed rats, Cd increased in blood and organs, more in pregnant rats, and in placenta and foetus whereas zinc increased in liver. Iron decreased in maternal organs and in foetus, whereas zinc decreased in maternal kidney and placenta. Liver copper was lower and kidney copper higher in all pregnant vs. non‐pregnant rats. Steroids in serum and placenta did not change. In conclusion, oral Cd exposure during rat pregnancy does not affect progesterone and testosterone at term. Transplacental iron and zinc handover are disrupted, which may put at risk the maintenance of foetal nutrition and viability. Copyright © 2014 John Wiley & Sons, Ltd.     

The evolutionary arms race between NK cells and viruses: Who gets the short end of the stick?

NK cells are innate lymphocytes that play a key role in the control of various viral infections. Recent studies indicate that NK cells may acquire some features of adaptive immune cells, including the formation of long‐lived memory cells. A large and growing body of data indicates that NK cells regulate the adaptive immune response as well. The function and the activation status of NK cells are tightly regulated by signals induced by a broad range of inhibitory and activating cell surface receptors and cytokines released by other immune cells. Here, we review the function of mouse NK‐cell receptors involved in virus control and in the regulation of the adaptive immune response. In addition, we discuss viral strategies used to evade NK‐cell‐mediated control during infection. Finally, the role of several activating Ly49 receptors specific for mouse cytomegalovirus (MCMV), as well as some controversial issues in the field, will be discussed.     

Short pain-provoked head-up tilt test for the confirmation of vasovagal syncope

We investigated a short pain-provoked head-up tilt (PP-HUT) and the Calgary Syncope Symptom Score in a group of patients with clinically diagnosed vasovagal syncope and group of neurological patients without transient loss of consciousness. We included 127 consecutive patients who were investigated in our laboratory. The group 1 included 56 patients who after appropriate investigations were diagnosed with vasovagal syncope. The group 2 included 70 neurological patients without transient loss of consciousness. The subjects were tilted to 70° for a maximum period of 10 min or until symptoms occurred. If there were no symptoms after initial 10 min, a painful stimulus with the insertion of 0.7 mm needle into the dorsum of hand subcutaneously for 30 s was performed with the patient in the tilted for further 5 min. Calgary Syncope Symptom Score was calculated for all patients. In the group 1, significantly higher number of patients had positive results on PP-HUT (36 vs. 6 patients, respectively; p < 0,001). There was no difference in the presence of orthostatic hypotension (8 vs. 15 patients, respectively; p = 0.36) or postural orthostatic tachycardia syndrome (3 vs. 1 patient, respectively; p = 0.32) between groups. PP-HUT had sensitivity of 65.9 % (95 % CI 0.49–0.79) and specificity of 89.7 % (95 % CI 0.75–0.97). The CSSS had sensitivity of 58.5 % (95 % CI 0.42–0.73) and specificity of 46.1 % (95 % CI 0.30–0.63). PP-HUT has a higher diagnostic rate than the CSSS and provides a rapid alternative to conventional methods.     

Postural orthostatic tachycardia syndrome associated with multiple sclerosis

BackgroundThe aim of this study was to determine if there is a difference in the frequency of postural orthostatic tachycardia syndrome (POTS) in patients with multiple sclerosis (MS) compared to patients with symptoms of orthostatic intolerance and with no evidence of MS or other neurological illness.MethodsWe analyzed data gathered from 293 patients who underwent the head-up tilt table test protocol. Group 1 included prospectively analyzed 112 with MS and group 2 included retrospectively analyzed 181 patients who were evaluated because of symptoms of orthostatic intolerance, and with no evidence of MS or other neurological illness. If POTS was identified the head-up tilt table test was repeated and supine as well as standing serum epinephrine and norepinephrine were determined.ResultsPOTS was identified in 39 patients: 21 (19%) in the MS group comparing to 18 (10%) in the non MS group (p = 0.035). There was no difference between groups in the occurrence of POTS associated syncope (p = 0.52). There was no difference between groups in the epinephrine or norepinephrine in supine and standing positions. While both standing epinephrine and norepinephrine levels were significantly higher compared to levels in the supine position in the non MS group, only standing norepinephrine levels were significantly higher in the MS group.ConclusionsThe results of this study suggest that POTS is associated with MS.