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PubMed2001

Evaluation of gingival recession in left- and right-handed adults.

Recession is the exposure of the root surface by an apical shift in the position of the gingiva. Several factors have been implicated in the etiology of gingival recession. The aim of this study was to assess the relationship between gingival recession and the hand, right or left, duration, frequency, and technique of tooth brushing in left- and right-handed adults in Erzurum, Turkey. Fifty five left-handed (35 female and 20 male) and 55 right-handed (35 female and 25 male) subjects were included in the study. The left and right hand positions of the subjects were determined by using Oldfield's Edinburg Inventory Index, and they were divided into two groups as left-handed and right-handed. The amount of gingival recession and localization, oral hygiene situations, gingival bleeding, toothbrushing duration, frequency, and techniques of subjects were evaluated. The relationship between the amount of gingival recession and localization and the subjects' hand, duration, frequency and technique of tooth brushing were examined. The data were evaluated with variance analysis and student's t test. The oral hygiene situations in right- and left-handed subjects were determined. On comparing the left-handed subjects with the right-handed ones, it was observed that the left-handed subjects had better oral hygiene than the right-handed. But, this case was not statistically significant (p > .05). In both right-handed and left-handed subjects, women had better oral hygiene than men (p < .01). The rate of gingival recession was found more in the left-handed than in the right-handed (p < .05). In the right-handed subjects, gingival recession was found in the premolar and canine regions of upper right and lower right jaw. A similar result was also observed in the left-handed subjects, because gingival recession was seen on their upper left and lower left jaw. Incisive teeth were affected at the same rate in the left-handed and right-handed. The gingival recession was seen more in maxillary jaw than in mandibular jaw in both groups. A statistically significant relationship between gingival recession and frequency duration, and technique of tooth brushing was found. While the greatest amount of gingival recession was found in horizontal scrub technique, gingival recession increased with increasing tooth brushing duration and frequency. The relationship between gingival recession and hand using in tooth brushing was determined.

Adult↗
PubMedDate not supplied

The Lyapunov exponent of heart rate dynamics as a sensitive marker of central autonomic organization: an exemplary study of early multiple sclerosis.

In a study of central autonomic dynamics in early multiple sclerosis, we measured the temporal oscillations of the momentary heart rate (heart rate dynamics). 11 young patients suffering from relapsing remitting definite multiple sclerosis in relapse-free and early stages of illness and 11 healthy controls were examined under vagotonic and sympathicotonic conditions. The temporal structure of the heart rate dynamics was operationalized phase-space analytically through the estimation of the largest Lyapunov exponent. Positive Lyapunov exponents were found in all participants under all conditions indicating deterministically chaotic heart rate oscillations. The variance analysis of these exponents detected no significant effect of sympathetic or vagal activity (experimental condition) but a significant group difference (p < .02). The multiple sclerosis patients were characterized by significantly lower Lyapunov exponents than the healthy controls. This finding suggests a more stable and thus less adaptive central-autonomic organization in early multiple sclerosis.

Adolescent↗
PubMed1996

Alcohol abuse exaggerates autonomic dysfunction in chronic liver disease.

BACKGROUND: Advanced chronic liver disease is characterized by peripheral arterial vasodilation and increased plasma catecholamine concentrations. These haemodynamic alterations may reflect impaired vascular responsiveness due to autonomic nerve dysfunction. METHODS: Three established non-invasive tests based on the heart reactions to deep breathing (expiratory/inspiratory (E/I) ratio) and to tilt (acceleration and brake indices) were used to evaluate age-related autonomic nerve function in 27 patients with chronic alcoholic and non-alcoholic liver disease. Liver function was estimated by demethylating capacity. The results were compared with a control group consisting of 56 healthy individuals. RESULTS: Overall, 12 patients (52%) had autonomic neuropathy (10 of 13 (77%) patients with alcoholic and 2 of 14 (14%) with non-alcoholic liver disease). Variance analysis showed that the age-corrected E/I ratio, but not the acceleration and brake indices, was significantly decreased compared with controls both in patients with alcoholic and non-alcoholic liver disease, indicating vagal nerve dysfunction (P < 0.0001 and 0.0133, respectively). The decrease in E/I ratio was also significantly more pronounced (-1.77 (0.62) (median (interquartile range)) versus 0.76 (0.70); P = 0.049) in patients with alcoholic compared with non-alcoholic liver disease. Furthermore, in contrast to non-alcoholics, patients with alcoholic liver disease were unable to increase their diastolic blood pressure after return to upright from a tilted position, indicating additional sympathetic neuropathy. CONCLUSIONS: Autonomic, mainly vagal, nerve dysfunction is common in patients with liver diseases and is further exaggerated by alcohol abuse. Autonomic neuropathy may contribute to altered vascular responsiveness in patients with chronic liver diseases.

Autonomic Nervous System Diseases↗
PubMed1997

Intestinal interleukin-8 concentration and gene expression in inflammatory bowel disease.

BACKGROUND: Interleukin-8 (IL-8) is an important cytokine for recruitment and activation of polymorphonuclear neutrophils (PMNs), cells that are abundant in the intestinal lesions of ulcerative colitis (UC) and Crohn's disease (CD). The present investigation was conducted to evaluate intestinal IL-8 concentration and IL-8 gene expression in parallel in inflammatory bowel disease (IBD) patients and a non-inflammatory control group. METHODS: The intestinal concentration of IL-8 was measured with a sandwich enzyme-linked immunosorbent assay (ELISA) technique (detection limit, 17.4 pg/mg protein), and relative quantitation of IL-8 mRNA transcript levels was done with a reverse transcription polymerase chain reaction (RT-PCR)-based method. Biopsy specimens from 66 humans who underwent colonoscopy--28 with UC, 18 with CD and colonic involvement, and 20 non-inflammatory disease-specific controls who subsequently were found to fulfill the diagnostic criteria for irritable bowel syndrome (IBS)--were included. None had received glucocorticoids within 3 months. RESULTS: Using a one-tailed variance analysis, a significant concordance between increasing IL-8 protein concentrations and disease activity was found both in UC and CD (P < 0.001), and only trace amounts were detected in IBS biopsy specimens. No differences were found between the two groups of UC and CD patients (P > 0.05), and no differences were found between quiescent IBD and IBS (P > 0.05). However, the PCR method showed IL-8 mRNA in 8 of 18 CD patients (44.4%; 95% confidence limits, 21.5-69.2%) and 7 of 28 UC patients (25.9%; 95% confidence limits, 11.1-46.3%), as compared with 0 of 20 IBS (P < 0.005). Increased IL-8 mRNA levels were found only in active CD, which was not the case in UC. No correlation was found between intestinal IL-8 ELISA and IL-8-mRNA levels (r = 0.24, P > 0.05). CONCLUSIONS: The observed correlation between disease activity and expression of the IL-8 gene in active CD colitis but not in UC and the increased IL-8 protein concentrations in affected intestinal segments of IBD as compared with the non-inflamed IBS indicate a possible transient IL-8 gene expression or altered mRNA stability in UC and CD, as is well known for other cytokines, such as IL-2. If so, it may form the basis of new therapeutic regimens for IBD like IL-10.

Adult↗
PubMed1984

Objective detection of averaged auditory brainstem responses.

Detection of an auditory brainstem response, ABR, usually relies on visual evaluation of two or more data acquisition runs of a fixed number of sweeps to determine if there is sufficient replication of the averaged waveforms to indicate a response. Visual interpretation can be difficult when the signal-to-noise ratio is poor because of either a small response or high levels of physiological background noise. Moreover, variations in the background noise from run to run can result in poor or spurious replications of component peaks and troughs in the waveform. A previous study (Elberling & Don, 1984) described a statistical approach for objective evaluation of the quality of an ABR recording. The method uses variance analysis in calculating the ratio of the magnitude of the ABR to the estimated averaged background noise. This study further applies this method to obtain a quantitative definition of the ABR threshold, to demonstrate its application in automatic threshold detection, and to estimate the number of sweeps required to reach detection criterion. Application of this method is valuable in reducing the variability of test interpretation and in maximizing the efficiency of recording ABRs by avoiding the averaging of excessive or insufficient numbers of sweeps. These improvements enhance the cost-benefit of ABR testing to the patient.

Adult↗
PubMedDate not supplied

Clinical, physiological and anatomical determinants for radiofrequency hyperthermia.

Temperature/time curves and corresponding CT scans of > 200 regional heat treatments with the hyperthermia system BSD-2000 in 43 patients have been analysed. In vivo variables and treatment parameters such as local specific absorption rate SAR, local relative SAR parallel SAR parallel, total power P, local cooling coefficients wb, and local steady-state temperature elevations delta Tss (above systemic temperature) have been determined. For determination of wb the well-known and accepted steady-state approach has been used, which was slightly modified for the purposes of this study. Specifically, comparison of cooling coefficients at the beginning and end of heat treatments were performed in tumours and normal tissues. Other variables are anatomical descriptors from CT scans, score of side effects plim, and various clinical factors. A variance analysis of the dependent variables, specifically delta Tss and parallel SAR parallel, is performed with respect to factors which were estimated as predictive. The intratumoral steady-state temperature elevations are determined by the perfusion-related cooling coefficients and local SAR to almost the same extent. Increase of cooling coefficients in tumours during the heat treatment characterizing the thermoregulatory potential have a slight but less important influence with respect to the achieved temperature elevations. SAR is influenced by several anatomical factors which determine the relative SAR distribution and clinical factors which limit the total power P. However, options for controlling present RHT systems in order to optimize the relative SAR distribution or to avoid hot spot phenomena appear limited. Three-dimensional modelling calculations show that the spatial arrangement of electrical interfaces emerging from bone and fat structures limits SAR control in available RHT technology and is mainly responsible for local power-dependent discomfort (Wust et al. 1994b). Some conclusions are drawn, about how technological development of hyperthermia technology can contribute towards overcoming this problem.

Female↗
PubMed1992

Circulating ICAM-1 levels in serum of uveitis patients.

Intercellular Adhesion Molecule-1 (ICAM-1) is a cytokine-inducible adhesion molecule expressed on cells of multiple lineages at sites of inflammation. Recently a truncated form of ICAM-1 has been discovered to be circulating in serum. This study reports on circulating serum (cICAM-1) levels in 132 uveitis patients (HLA-B 27 pos. acute anterior uveitis (AAU); HLA-B27 neg. anterior uveitis (AU); intermediate uveitis (IU); heterochromic cyclitis Fuchs (HCF); sarcoidosis; Toxoplasmosis). Measurement of circulating ICAM-1 serum levels was performed using a monoclonal antibody based ELISA, with healthy blood donors serving as the control group. Applying multiple variance analysis and the Student Newmann-Keuls test we found a statistically significant elevation of serum cICAM-1 level in the HLA-B 27 neg. AU group (n:31), in the IU group (n:25) and in patients with sarcoidosis (n:18). Serum levels of HLA-B27 pos. AAU patients, patients with HCF and patients suffering from ocular toxoplasmosis did not differ significantly from levels of the control group.

Acute Disease↗
PubMed1980

Prognostic significance of distal blood pressure measurements in patients with severe ischaemia.

The clinical course was followed and the ankle and toe blood pressures were measured with the strain gauge technique on 5 occasions during 2 years in 43 patients with pain at rest and/or ischaemic ulceration due to severe ischaemia of the legs on the basis of occlusive arterial disease. Although arteriosclerosis of the legs in non-diabetic patients is generally considered a benign disease from the standpoint of limb survival, the critical level of TPI (systolic toe blood pressure/systolic arm blood pressure) was found to be 0.07 as a TPI below this value was associated with an overall 82% risk of amputation. With TPI above 0.07, the chance of successful conservative therapy was about 40%. Diabetics with severe ischaemia must be regarded as a high risk group in respect of amputation (64%) and lethality (64%). A variance analysis was made on the pressure data: In patients with low pressure peripheral vascular beds, the TPI must change more than 0.15 units from one examination to another before the alteration can be considered significant at the 99% confidence level.

Aged↗
PubMedDate not supplied

Specialized PC software package for creation of computer systems supporting partial diagnostics based on numerical results of medical examinations.

Computer scientists creating computer systems supporting partial diagnostics based on numerical results of medical examinations always follow a similar method. Why not algorithmize this procedure? This was the main reason for preparation of the specialized PC software presented in the paper. The software is addressed to clinicians-scientists and enables such users to create by themselves (with no need of programming) practically useful computer systems for differential diagnosis of chosen diseases. These generated systems are assigned to an end-user, i.e. any physician interested in a partial diagnosis of the considered type. They perform classification of patients on the basis of numerical results of the examinations selected for the training databases. The software is based on a statistical approach; multi-dimensional variance analysis and discriminant analysis methods have been used. The pilot version of the software (experimentally implemented in a Warsaw clinic) and an outline of planned work are presented.

Algorithms↗
PubMed1983

Myonecrotic gas gangrene of the extremities.

Twenty-three patients with proven myonecrotic gas gangrene of the extremities caused by Clostridium perfringens bacteria were treated by a combination of surgical measures, benzyl-penicillin and hyperbaric oxygen at three atmospheres. 87 per cent (20/23) of the cases were cured and half of the surviving patients (10) had to be amputated at least one level higher than on admission. No single factor could be established that influenced the course of the infection comparing age under and over 50 years, vascular insufficiency and normal vascular conditions, and toxicity and non-toxicity. Nor did the level of the infection of the limb seem to have any influence. The frequency of death in relation to the described variables could not be established when multi-variance analysis was used.

Adolescent↗
PubMed1980

Fibrinogen catabolism in patients with postoperative infectious complications.

The biological half-life (TB) of 125I-fibrinogen was studied in 21 surgical patients, using a precordial counting technique. TB was calculated for the first 4 postoperative days (first phase) and for the 5th to 10th days (second phase). Daily calculations of TB were undertaken in 15 patients. In patients with a normal postoperative course, TB was 2.31 days (first phase) and 3.80 days (second phase). In patients with a postoperative infectious complication (PIC), TB was 1.74 days (first phase) and 2.21 days (second phase), which was significantly shorter than corresponding values in patients with normal postoperative course. The mean of the daily values of TB was significantly shorter in the second phase in patients with PICs compared to those with a normal postoperative course. Co-variance analysis of daily TB in the first and second phases showed no significant difference in 25/30 phases (83%). It is suggested that TB of 125I-fibrinogen can be used as a complement to the clinical diagnosis of PIC. Further studies are desirable to confirm the method.

Bacterial Infections↗
PubMedDate not supplied

Optic nerve head blood flow using scanning laser Doppler flowmetry after laser in situ keratomileusis.

PURPOSE: To investigate ocular blood flow changes following laser in situ keratomileusis (LASIK) in myopic eyes. METHODS: Seventeen eyes of ten myopic patients were included in the study. Mean age of the seven men and three women was 29.1+/-2.5 years. Mean spherical equivalent refraction was -7.70+/-2.52 D. LASIK was performed with the Hansatome microkeratome and Summit SVS Apex excimer laser. Optic nerve head blood flow was measured by using the Heidelberg Retinal Flowmeter preoperatively and postoperatively at 1 day, 1 week, and 1 month. Preoperative ocular blood flow data (blood flow, volume, velocity) were compared with postoperative data using variance analysis. Correlation analysis was performed for age of patients, suction time, and ocular blood flow data. RESULTS: Mean suction time was 19+/-7 seconds. There was no significant correlation between suction time, age, and ocular blood flow. We found an increase in blood flow at the lamina cribrosa taken 1 day postoperatively (P=.04). Blood flow returned to preoperative values at the 1-week and 1-month measurements in the lamina cribrosa region. There was no significant change in ocular blood flow data in the neuroretinal rim except an increase in velocity at the lower nasal quadrant on postoperative day 1 (P=.03). CONCLUSIONS: LASIK caused a temporary increase in blood flow at the lamina cribrosa region of the optical nerve head in healthy myopic eyes. The increase in blood flow may suggest a compensatory change for maintaining blood flow in the ocular nerve head following LASIK-induced ischemia.

Adult↗
PubMed2004

Physical properties of different composites.

The purpose of this study was to determine the flexural strength (FS), flexural modulus (FM), depth of cure (DC), polymerization shrinkage (PS), and microhardness (VH) of the following composites: Two packable composites--Filtek P-60 and Solitaire 2; One ion-releasing composite--riston AT; and Two hybrid composites--Charisma and Filtek Z-250. Data of the different tests conducted were obtained as follows: FS and FM data were determined with a universal-testing machine; Polymerization shrinkage was determined using the apparatus of Watts and Cash; Depth of cure was measured with a micrometer (Mitotuyo, UK); and Microhardness was measured with a Shimadzu Microhardness tester (500 g, 15 seconds). All data of the different tests were statistically analyzed by one-way variance analysis (ANOVA), which yielded the following results: Filtek Z-250 showed the statistically highest flexural strength and modulus values. Solitaire 2 exhibited the highest shrinkage, while the volumetric shrinkage results of Filtek Z-250 and Filtek P-60 ranked the lowest. For depth of cure, there were no statistically significant differences among all materials tested (p<0.05). Microhardness results revealed the following tendency: Filtek Z-250 = Filtek P-60 > Ariston AT = Solitaire 2 = Charisma.

Bisphenol A-Glycidyl Methacrylate↗
PubMed1999

Clinical experience with gabapentin in patients with bipolar or schizoaffective disorder: results of an open-label study.

BACKGROUND: This study was carried out to evaluate the efficacy, tolerability, and safety of gabapentin as an adjunctive treatment in patients with bipolar or schizoaffective disorder with manic or hypomanic symptoms. METHOD: Twenty-five patients fulfilling DSM-IV diagnostic criteria for bipolar I disorder or schizoaffective disorder underwent a 16-week, open-trial treatment with gabapentin. Symptom severity was measured using the Clinical Global Impressions scale (CGI) and the Brief Psychiatric Rating Scale (BPRS). Baseline scores and final scores were compared by using the Student t test and the Friedman range variance analysis. RESULTS: Twenty-two patients (88%) completed the 16 weeks of treatment with gabapentin; 19 (76%) had a positive response as measured by changes in CGI and BPRS scores. The mean dose was 1440 mg/day. The only side effect observed was oversedation, which decreased with continuing treatment. CONCLUSION: Gabapentin was effective in the treatment of mania and hypomania in patients with bipolar and schizoaffective disorders. If confirmed in controlled studies, these findings suggest that gabapentin represents a well-tolerated, rapidly acting antimanic agent.

Acetates↗
PubMed1988

Problems in the evaluation of occupational health promotion programs: a case analysis.

This study investigates, in a case study setting, whether participation in the Kimberly-Clark Corporation Health and Weight Loss Program can be associated with reduced participant health care claims. A pretest, post-test comparison group research design is utilized to ascertain whether there have been any measurable health care cost savings for participants versus their non-participating matched employee counterparts. The significance of any measured differences is then tested through analysis of variance and analysis of covariance. In addition, results are reported from tests designed to assess whether any specific employee subpopulations appeared to differentially benefit from program participants in terms of reduced health care cost incurrence. Finally, tests are run to provide further assurance that those potential test subjects who were excluded from the final sample did not systematically differ from the final sample subjects. This paper also illustrates, with references to the present study, the difficulties of adapting behavioral and social science research techniques to actual occupational health promotion settings.

Body Weight↗
PubMed1994

Introduction of managed care plans in a cardiac surgery unit.

Changes to output-based funding for health care as occurred recently in Victoria, and the goal of continuous improvement in quality of care, have provoked a rationalization of resource utilization and a greater focus on the process and outcomes of care in acute hospitals. The use of clinical management plans (CMPs) to monitor the efficiency of processes and the achievement of outcomes (managed care systems) is one approach to these challenges. A pilot study undertaken in the cardiac surgical unit at the Royal Melbourne Hospital is used to highlight the major considerations that need to be addressed when administering CMPs. These were the multidisciplinary, patient-focused approach of the managed care system, integration of the plans into the patient documentation system and the opportunities offered to research by variance analysis.

Cardiac Surgical Procedures↗
PubMed1998

Casemix perspectives for clinicians in the private sector.

All private hospitals and clinics must now supply deidentified data, using AN-DRG classification, on all admitted patients to the Private Hospitals Data Bureau. Contracts between health funds and hospitals must also be described on the basis of AN-DRGs, which will enable funds to undertake hospital variance analysis. These data provide the foundation for nationally developed clinical pathways and utilisation reviews which could modify clinical practice, improve standards and reduce health costs. Clinicians must understand and participate in these changes, and adequate safeguards are needed to protect them against loss of their clinical integrity, and against inappropriate discretionary control by private hospitals, healthcare corporations and health insurers.

Australia↗
PubMed1976

[Quantitative studies on the dendritic spine distribution on the lamina-5 pyramidal cells in the anterior gyrus cinguli of the rat].

At three months old male rats the spine-distribution of the main dendrite and of the apical and basal dendrites of 36 lamina V-pyramidal cells of the regio cingularis (anterior cingulate cortex) was analyzed (from every subregion -- neocortex, mesoneocortex, mesoarchicortex -- 12 neurons). 1. The limbic pyramidal neurons show the same spine-distribution at their main dendrite as neocortical neurons of other brain regions and other mammal-species do: after an initial segment with poor spines only there follows an rapid increase of the spine-values with an amount at a range of 150 mum from the perikaryon, thereafter spine-values decrease continuously and slowly up the branching into the terminal bundle. 2. Basal and apical lateral dendrites however show another spine-distribution: basally there is an increase of the spine-values from the 1st up to the 3rd order, followed by a decrease at subsequent orders. Apically spine-density decreases from the 1st up to the 4th order. 3. The spine-distribution at the parts of the dendritic tree is discussed as a general biological sign of pyramidal cells. 4. The total number of spines of lamina V-pyramidal cells in the regio cingularis (anterior cingulate cortex) is less than those in the sensomotoric cortex and in the hippocampus, which corresponds with the lower differentiation of the limbic cortex. 5. By means of a variance-analysis the pyramidal spine-values of the three subregions were compared: concerning the total number of spines of a pyramidal neuron there are significant differences between the three subregions; the values are in the ratio of 3 to 2 to 1 (Regio praecentralis agranularis, 2461; mesoneocortex, 1664; mesoarchicortex, 800). The significantly least spine-density of all parts of the dendritic tree you can find in lamina V-pyramidal cells of the mesoarchicortex. 6. The equality of the basal and apical spine-values in the mesoneocortex is due to less specialization of these neurons. 7. The spine-values for a single dendritic field (EDF) show the differences between the limbic subregions clearly: there are significant differences between the three subregions concerning not only the number of spines but also the spine-densities apically and basally.

Animals↗