Evaluation of a flow cytometry-based assay for natural killer cell activity in clinical settings.

Natural killer (NK) cells are not only important in first line defence against viral and bacterial infections, but also in immune surveillance of malignant cells and thus NK cell cytotoxicity is primary indicator of immune function. Although chromium release assay is recognized as 'gold standard' for measuring NK cell activity, it has disadvantages like use of radioactive compounds, poor loading and high spontaneous release. It is difficult to perform this assay in clinical laboratory because of difficulties with disposal of radioactive waste and standardization problems. We describe a flow cytometry-based assay for the measurement of NK cell activity by incorporating fluorescent dye, DiO, into membranes of target cells. NK cell activity was measured at baseline, 1 and 4 weeks follow-up in 20 normal healthy individuals on a dietary supplement immunomodulator to enhance NK cell function. Mean baseline NK cell activity percentage (21.5; SD = 9.3) increased significantly to a maximum level at 1 week (31.3%; SD = 7.9; P = 0.007) and then returned to baseline level at 4 weeks (21.5; SD = 8.3). An important feature of flow cytometry-based assays is its ability to discriminate effector cells from target cells, and potential for explaining molecular interactions underlying target cell lysis. Under clinical settings, this assay will be of interest for frequently monitoring immunological status of patients on treatment for various diseases that affect their immune status. The assay is easy to perform without using radioactive material and thus could become a tool for monitoring pathogenesis and immune reconstitution.

Non-voice-related throat symptoms: comparative analysis of laryngopharyngeal reflux and globus pharyngeus scales.

BACKGROUND: This study calculated the comparability of two throat symptom assessment scales devised to evaluate either laryngopharyngeal reflux or globus. SETTING: United Kingdom hospital out-patient departments. METHOD: A total of 334 subjects, with and without throat symptoms, completed the Reflux Symptom Index and/or the Glasgow and Edinburgh Throat Scale. The following were calculated for the resultant data: Cronbach's α coefficient, principal component analysis, Kaiser normalisation, varimax and oblimin rotation, and eigenvalues. RESULTS: Analysis of data from the Reflux Symptom Index and the Glasgow and Edinburgh Throat Scale revealed clearly similar symptom domains regarding (1) coughing and blockage, and (2) globus or postnasal drip or throat-clearing, as did combined analysis of their amalgamated items. Both instruments had good overall internal consistency (α = 0.75 and 0.81, respectively). The 'heartburn or reflux' item in the Reflux Symptom Index mapped poorly to each underlying factor. DISCUSSION: The most commonly used laryngopharyngeal reflux and globus assessment questionnaires appear to detect very similar symptom clusters. The management of throat disorders may previously have been over-reliant on the presenting pattern of throat symptoms. Our findings indicate a need to revisit the traditional clinical classification of throat symptoms.

Estimation of nicotine content in popular Indian brands of smoking and chewing tobacco products.

OBJECTIVES: To estimate the nicotine content of some popular Indian brands of smoking tobacco (cigarettes and bidis) and pan masalas (chewable tobacco). MATERIALS AND METHODS: Commercially available cigarettes, bidis, and pan masalas (chewable tobacco) were obtained from local retail outlets for the study. Nicotine was estimated using gas-liquid chromatography. RESULTS: The analyses showed relatively higher levels of nicotine in tobacco from bidis (26.9 mg gm) as compared to cigarettes(15 mg/gm); the difference is statistically significant ( P P > 0.01). Nicotine concentration in chewing tobacco was 3.4 mg/gm. CONCLUSION: The study concludes that the nicotine content of Indian brands of smoking tobacco was slightly high compared to other international brands. Higher concentration of nicotine was found in bidis compared to cigarettes. The nicotine content in commercially available chewing tobacco products was found to be much lower than in the smoking form of tobacco, but the average daily consumption made it comparable to the smoking form.

A comparative study of the efficacy of four different bristle designs of tooth brushes in plaque removal.

BACKGROUND: The aim of the study was to compare the efficacy of four most commonly used bristle designs of toothbrushes in plaque removal. MATERIALS AND METHODS: The study was a randomized 4 cell, examiner blind cross-over design assessing the plaque removal efficacy of all four brushes on a single occasion. Sixteen subjects aged 14-15 years participated in the study. On day 1 of each test period, the subjects were rendered plaque free and were asked to suspend oral hygiene practices for 24 hours. On day 2, the subjects were scored for plaque prior to brushing using the Turesky-Gilmore modification of Quigley-Hein plaque index. The subjects then brushed with the allocated toothbrush for 2 minutes and the post-brushing plaque scores were assessed. A wash-out period of 4 days was allowed between the test periods. RESULTS: All the brushes showed a significant reduction in the post-brushing plaque scores ( p < 0.001). The mean reduction in the plaque scores for all the brushes was around 53%. The percentage plaque reduction was greater in the anterior surface than the posterior surface (59.6 +/- 7.45% vs. 49.83 +/- 4.35%). The percentage plaque reductions in the upper, lower, buccal and lingual surfaces were similar. No significant difference in the reduction of plaque scores between the four brushes was seen. CONCLUSION: The data derived from the study supports the contention of many researchers that there is no single superior design of manual toothbrush. Though minor and some site differences in favor of the brushes were seen, they were not statistically significant.

What is the severity of globus sensation in individuals who have never sought health care for it?

OBJECTIVES: To assess the pattern and severity of globus-type symptoms, as measured by the Glasgow Edinburgh throat scale, in individuals who had never sought health care for a feeling of something in the throat, in order to generate the first useful normative dataset for the Glasgow Edinburgh throat scale. METHODS: One hundred and seventy-four participants recruited from non-ENT clinics completed the Glasgow Edinburgh throat scale. They were distributed among three age groups (21-45, 46-65 and >65 years). RESULTS: The commonest throat symptoms reported were 'coughing to clear the throat', followed by 'catarrh down the throat' and 'discomfort/irritation in the throat'. CONCLUSIONS: The results of the study--a normative dataset for the Glasgow Edinburgh throat scale--may form the basis for: (a) the use of the Glasgow Edinburgh throat scale in primary care to identify patients for whom referral to secondary care may be appropriate; (b) monitoring the natural history of globus sensation; and (c) assessing response to intervention, in terms of resolution to baseline population levels of symptom severity.

Marine-based waste stabilisation ponds: an evaluation of the hydraulic viability.

Marine-Based Waste Stabilisation Ponds, formed by floating boom/skirt curtain enclosures anchored in sheltered waters, have recently been proposed for provision of low-cost effluent treatment facilities where land availability is limited in rapidly expanding coastal cities in the Third World. This paper outlines findings from a viability assessment, which drew on a preliminary site evaluation and baseline environmental survey (for a site in sheltered waters in the Far East), laboratory studies involving scale model tests in wave/wind/current flumes, and a structural and design loading study. It focuses on hydraulic and hydrodynamic considerations and reports the study's conclusions.

Novel boom/skirt systems for improvement of water quality in estuarial impoundments subject to saline influx.

The recent popularity of esturial barrage construction in the UK has been driven largely by commercial and amenity interests arising from the need to rehabilitate tracts of derelict urban land. Formation of a permanent water body to replace the tidal regime hides unsightly mud banks and facilities ready access for water based recreation. Unfortunately, in most cases, and presumably arising from upstream extreme flood risk assessment, the barrier is designed to overtop under the highest (spring) tidal peaks so allowing a substantial influx of heavier saltwater into the impoundment on a regular basis. This might well substantially exceed influx via any navigational lock operations. The problem created by the salt water is that its greater density causes stratification in the impounded water body. In times of low freshwater flow little mixing takes place and the normal action of the wind, in circulating and aerating the water body, will only extend within the lighter and often thin surface freshwater layer. The consequence is that little reoxygenation of the lower layers takes place leading to depressed dissolved oxygen levels and possible anoxia. Sluice provision in the barrage may be ineffective in expelling the saline layers, so this water remains near stagnant and deteriorates in quality due to sediment oxygen demands until a major fluvial flood, or new saline influx, is able to effectively mix the waters. Conventional continuous surface releases through fish pass and/or by crest overspill ensure the preferential release of the freshwater rather than the problematic saltwater. Retrofitting of novel low cost floating boom/skirt baffle system is proposed here for alleviation of the problem.

Upper limb in injuries in dry ski slope skiing--a continuing problem.

The aim of this study was to assess how common injuries to the upper limbs are from dry ski slope skiing, to document the pattern of injury to the upper limbs from dry ski slope skiing and to discuss preventative measures. Skier's experience was also determined. The study was carried out on 174 patients attending the accident and emergency department over a period of 3 years who had sustained injuries from dry ski slope skiing. Prospective registration was used to collect the data. Sixty-seven per cent of the patients had received instructions prior to skiing. Upper limb injuries outnumbered lower limb injuries by a ratio of 7.9 to 1. Thumb injuries outnumbered other injuries in the upper limb. The mechanism of injury was due to a fall in 94.2% of patients. It is concluded that the lattice network on dry ski slopes significantly contributes to the platform of injuries to the upper limbs, and ways in which the lattice network may be improved are recommended.

Cardiovascular effect of intravenous lipid A in rabbits.

The in vivo cardiovascular effect of intravenous administration of monophosphoryl lipid A (mp-lipid A) and diphosphoryl lipid A (dp-lipid A) in awake New Zealand white rabbits was investigated. Observed changes were evaluated in comparison to a control group and an endotoxin-treated group. Rabbits given lipid A showed a significant depression in cardiac index (p less than .025), mean arterial pressure (p less than .025, dp-lipid A only), arterial carbon dioxide tension (p less than .025), and total leukocyte count (p less than .05) compared to controls. Animals receiving lipid A tended to respond overall in a manner closely matching that of the endotoxin group. Dosages of lipid A given were approximately 3.5 times larger than the endotoxin dosages with respect to actual number of molecules administered (1.25-2.0 times larger by mass). These results indicate that lipid A is active in producing the cardiovascular and leukopenic effects characteristic of experimental septic shock.