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A novel system for large-scale gene expression analysis: bacterial colonies array.

In the present work, we report the use of bacterial colonies to optimize macroarray technique. The devised system is significantly cheaper than other methods available to detect large-scale differential gene expression. Recombinant Escherichia coli clones containing plasmid-encoded copies of 4,608 individual expressed sequence tag (ESTs) were robotically spotted onto nylon membranes that were incubated for 6 and 12 h to allow the bacteria to grow and, consequently, amplify the cloned ESTs. The membranes were then hybridized with a beta-lactamase gene specific probe from the recombinant plasmid and, subsequently, phosphorimaged to quantify the microbial cells. Variance analysis demonstrated that the spot hybridization signal intensity was similar for 3,954 ESTs (85.8%) after 6 h of bacterial growth. Membranes spotted with bacteria colonies grown for 12 h had 4,017 ESTs (87.2%) with comparable signal intensity but the signal to noise ratio was fivefold higher. Taken together, the results of this study indicate that it is possible to investigate large-scale gene expression using macroarrays based on bacterial colonies grown for 6 h onto membranes.

Algorithms↗

Optimizing refolding and recovery of active recombinant Bacillus halodurans xylanase in polymer-salt aqueous two-phase system using surface response analysis.

An experimental design was used to determine optimal conditions for refolding of a recombinant thermostable and alkaline active xylanase from Bacillus halodurans in PEG-phosphate two-phase system. The influence of different experimental variables on the enzyme recovery has been evaluated. To build the mathematical model and minimize the number of experiments for the design parameters, response surface methodology with a face-centered central composite design (CCF) was defined based on the conditions found by preliminary tests that resulted in the highest refolding yield. The adequacy of the calculated model for the response was confirmed by means of variance analysis and additional experiments. Analysis of contours of constant response as a function of pH, polyethylene glycol (PEG) molecular weight and concentration, and salt concentration for different enzyme loads revealed different effects of these five factors on the studied parameters. Recovery of more than 92% active xylanase was predicted for a system with 18.3% (w/w) PEG 1000, 14.4% (w/w) phosphate at pH 8.5, and enzyme load corresponding to a protein concentration of about 0.05 mg/g system. The yield of the refolded enzyme was found to be optimal at 22 degrees C. The validity of the response model was verified by a good agreement between predicted and experimental results.

Analysis of Variance↗

A biomechanical evaluation of mandibular condyle fracture plating techniques.

OBJECTIVES: The purpose of this investigation was to evaluate the biomechanical behavior of various rigid internal fixation techniques for mandibular condylar process fractures. MATERIALS AND METHODS: Synthetic mandible replicas (Synbone, Landquart, Switzerland) were used to evaluate a control, and four monocortical mandibular condyle plating techniques. Each group was subjected to linear loading in lateral to medial, medial to lateral and posterior to anterior directions by an Instron 1331 (Instron, Canton, MA) servohydraulic mechanical testing unit. Yield load, yield displacement, and stiffness were measured. In addition, each group was subjected to torsional loading using an Instron 8521 (Instron). Yield torque, yield rotation, and stiffness were measured. Five samples were tested for each group and method of loading (n = 100). Means and standard deviations were derived and compared for statistical significance using a 1-way analysis variance (P <.05). Third-order polynomial best-fit curves were also created for each group to further evaluate and compare the mechanical behavior. RESULTS: Statistically significant differences were noted between fixation groups for the different mechanical measures evaluated under the different conditions of linear loading. Statistically significant differences were noted between groups for yield rotation during torsional loading. Although different in magnitude, similar patterns of mechanical behavior were observed in the third-order polynomial best-fit curves for lateral to medial loading, medial to lateral loading and torsional loading. For posterior to anterior loading, different patterns of mechanical behavior were noted between the experimental groups, but similar behavior was noted between the control and mini dynamic compression plate CONCLUSIONS: While differences were noted between each of the fixation systems in their abilities to resist loads under the conditions tested, the mini dynamic compression plate provided the most favorable mechanical behavior. Based on the presumed clinical parameters, we can suggest that none of the systems evaluated were ideal for the treatment of mandibular condyle fractures, but that the mini dynamic compression plate is the closest to an effective means for reconstruction.

Analysis of Variance↗

Immunohistochemical staining properties of PCNA, Ki-67, p53, beta-hCG and HPL in trophoblastic disease.

OBJECTIVE: In this study proliferating markers PCNA (proliferating cell nuclear antigen) Ki-67 and mutation of supressor gene p53 were investigated in gestational trophoblastic disease (GTL). These markers were tested by using immunostaining with beta subunits of human chorionic gonadotropin (hCG) and human placental lactogen (HPL). MATERIAL AND METHODS: Twenty curetting samples, 20 spontaneous abortions, 16 hydatidiform moles and two choriocarcinomas were studied and compared. Hydatidiform moles were subdivided into 10 complete and six partial moles by using flow cytometry analysis. All slides were stained with PCNA, Ki-67, p53, hCG, and HPL immunohistochemically. PCNA and Ki-67 stained slides were studied quantitatively to determine the PCNA and Ki-67 index. Other slides that were stained with p53, hCG, HPL were evaluated according to staining percentage and intensity. Staining properties of all groups were compared with each other. Variance analysis and the Mann Whitney U test were used for statistical analysis. Choriocarcinomas were not included in the statistical analysis. Ki-67 and the PCNA index in two choriocarcinoma cases found 81.4% and 41%, and 44% and 64%, respectively. One case was stained in 70% with (++) intensity by p53. While both were stained in 80% with (++) intensity by hCG, one was stained in 30% field (+) intensity by HPL. RESULTS: The four groups of complete and incomplete diagnosed hydatiform moles, spontaneous abortions and retention curettage were matched in pairs and evaluated according to the PCNA index. This index showed significant differences among the groups. The differences among the Ki-67 index, p53, hCG and HPL staining properties were not statistically significant. CONCLUSION: Our findings showed that PCNA is a significant and useful marker for trophoblastic diseases and can be used as a prognostic factor.

Adult↗

Analysis of circadian periodicity of plasma cortisol in normal man and in Cushing's syndrome.

In normal subjects, adjusted to a circadian environment, half-hourly plasma cortisol levels over a 24-h span (time series, TS) outline a circadian sinusoidal pattern that may be masked by superimposed short-lived oscillations. The periodogram objectively defines the features (amplitude, phase) of this pattern in individual TS and, more efficiently, in the average and concatenation of homogeneous TS. Concatenation is a procedure by which homogeneous short TS are attached one after the other. Homogeneity is inferred by variance analysis and by a new measure, h, with statistical significance, derived from the spectrum of the concatenated TS. Through concatenation, autocovariance for periodicity identification becomes possible. The TS from three groups of volunteers are highly homogeneous and have a predominant, statistically significant amplitude with peak time near 1100 h. The patterns from patients with Cushing's disease differ markedly in their means and periodic features; by the above criteria, we identify a subgroup with significant h measure and 24-h amplitude. This analysis provides a tool for investigation of the circadian clock in man.

Adolescent↗

[Treatment motivation and results of inpatient psychotherapy for women with depressive disorders: a prospective study].

Whether the treatment results in inpatient psychotherapy are significantly influenced by the patient's motivation is a subject of discussion. The goal of this study was to assess whether the primary motivation for therapy in depressive women influences the results of psychotherapeutic treatment. In a prospective study, the monitored results from 64 female inpatients (32 who were highly motivated to enter therapy, and 32 who were minimally motivated) were compared to each other. The period of observation was six weeks. As instruments of assessment, the Fragebogen zur Therapiemotivation (FMP) (Questonnaire on Motivation for Entering Therapy) and the Beck Depression Inventory (BDI) were aministered upon admission; after the fourth and sixth weeks of therapy, the Veränderungsfragebogen des Erlebens und Verhaltens (VEV) (Questionnaire of Changes in Experience and Behavior) was administered as well. All patients who had applied for a pension were found in the group of less motivated patients and consolidated into a subgroup. The analysis was carried out according to the intent-to-treat principle. The variance analysis for the repeat measurements showed significant differences on all the FMP scales and on the BDI (all P< 0.001). The measurements with VEV likewise resulted in a significant difference (P< 0.01). The subgroup of "pension patients" showed significantly less change in all three of the above measurements. Patients with depressive symptomology who essentially are relatively highly motivated for therapy could profit significantly more from inpatient psychosomatic treatment than those who are less motivated. Establishing and developing motivation prior to inpatient hospitalization could possibly contribute to more efficient and cost-effective clinical treatment. Where legal proceedings pertaining to a pension are pending, relatively less motivated patients fare significantly worse not only in their motivational development for therapy, but also in their final treatment results. It should be noted, however, that the relatively small random sample, the restricted blinding, which was only partially possible, could have led to possible distortions.

Attitude to Health↗

Effect of educational level, gender and age on the performance in a multi-user computerized psychometric test system for use in clinical pharmacological studies.

197 native, drug-free healthy young volunteers performed psychometric tests on a single occasion, using a new multi-user computerized test system which consists of tests of simple reaction time, complex reaction time, vigilance, concentration, motor coordination, short-term memory (word pairs or figures) and abstract language-free reasoning (2 versions). Normality of distribution of all psychometric variables was checked. For the reasoning tests and the memory tests, internal consistency and parallel test reliability were determined. Cross-correlations between the variables and factor analysis were done to evaluate whether different tests measure different brain functions. Multivariate variance analysis was carried out to test the effect of the independent factors school education, gender and age on the performance in the psychometric tests. Subjects with a lower school education level performed worse in the reasoning tests, the concentration test and the memory tests. Females were slower in the coordination test and made fewer correct solutions in the concentration test. Older subjects performed worse in the reasoning tests and had a longer working time in the memory tests than younger ones. The results show the necessity of psychometric screening of volunteers before recruitment for clinical pharmacological psychometric studies in order to reduce-individual variability.

Adolescent↗

Red blood cell variables in highly trained pubescent athletes: a comparative analysis.

BACKGROUND: A suboptimal haematological status has often been recorded in athletes involved in intensive physical activity. There have even been reports of "sports anaemia" associated with intensive physical exercise. However, studies on the effect of different types of exercise practiced over a long period of time on the red blood cell variables in pubescent athletes are very few. AIM: To assess the basic red blood cell variables in highly trained pubescent athletes from different sports and to compare the results with those for a control untrained group. Sex related differences in these variables were also assessed. METHODS: 876 highly trained athletes (559 boys and 317 girls) were included in the study. Their mean (SEM) age, weight, and duration of training were: 14.01 (0.06) years, 56.24 (0.52) kg, and 3.52 (0.07) years respectively. The control group consisted of 357 untrained subjects (171 boys and 186 girls) with mean (SEM) age and weight of 14.58 (0.09) years and 57.75 (0.67) kg. The group of athletes was divided into seven subgroups according to the sport practiced: athletics (105), swimming (107), rowing (230), wrestling (225), weight lifting (47), various team sports (92), and other sports (67). Venous blood samples were drawn from the cubital vein, and the red blood cell count, packed cell volume, haemoglobin concentration, and mean corpuscular volume were measured. Statistical indices were computed for each group and for each variable, and analysis of variance factorial analysis was performed to evaluate the statistical significance of the differences detected. RESULTS: The highly trained group was found to have lower red blood cell count, packed cell volume, and haemoglobin concentration (p<0.001) than the control untrained group (4.61 (0.01) x 10(12)/l v 4.75 (0.02) x 10(12)/l, 0.389 (0.001) v 0.404 (0.002) l/l, and 133.01 (0.38) v 139.9 (0.62) g/l respectively). These variables were lower for the boys of the trained group than for the boys of the control group (p<0.001), and similarly for the girls (p<0.001). The lowest red blood cell count, packed cell volume, and haemoglobin concentration were measured in blood samples from the boys of the swimming subgroup (4.54 (0.06) x 10(12)/l, 0.386 (0.006) l/l, and 129.38 (1.80) g/l respectively) and the rowing subgroup (4.66 (0.03) x 10(12)/l, 0.400 (0.003) l/l, and 136.21 (0.94) respectively). The same distribution was found for the girls: lowest in the rowing subgroup (4.32 (0.04) x 10(12)/l, 0.314 (0.003) l/l, and 124.27 (0.93) g/l) and the swimming subgroup (4.40 (0.05) x 10(12)/l, 0.375 (0.005) l/l, and 125.90 (1.30) g/l). No differences were found in the mean corpuscular volume. CONCLUSIONS: Continuous (more than one year) high intensity sports training (twice a day/five days a week) results in a decrease in the basic red blood cell variables in pubescent boys and girls, this being most pronounced in the submaximal sports.

Adolescent↗

Characterization of spermatozoa by planar morphometry.

OBJECTIVE: To define the morphometric characteristics of normal sperm heads, and compare them to sperm head measurements used to define normal morphology using strict criteria. DESIGN: Computerized image analysis of selected normal and abnormal seminal fluid specimens collected for routine male fertility studies. SETTING: Research laboratory at the Department of Medical Technology, Bowling Green State University, Bowling Green, OH. PATIENTS: Sixty adult male patients who submitted semen samples for routine analysis. Fifty percent had normal seminal fluid analysis results. The remaining 50% demonstrated abnormal sperm morphology. CRITERION STANDARD: Microscopic evaluation of sperm head morphology. Sperm fitting the criteria of normal as defined by WHO (1987 and 1992) and Kruger (1988) were classified as normal. Sperm with a post nuclear area of less than 40% were classified as acrosomal deficient. MAIN OUTCOME MEASURES: Measurements made from stained seminal fluid smears included sperm head area, perimeter, acrosomal area, percent acrosome, Ferret's diameters, aspect ratio, shape factor, and specific length. Normal sperm heads (NL group) were compared to sperm heads demonstrating an acrosomal deficiency (AD group) for statistically significant differences using multivariate analysis of variance (MANOVA) and analysis of variance (ANOVA). Stepwise discriminant analysis was used to remove duplicating variables. Discriminant analysis was used to classify the sperm heads into NL and AD groups. Receiver-operating characteristic (ROC) curves were applied to the 2 most influential variables in order to identify a cutoff that best distinguishes normal from acrosomal deficient sperm heads. RESULTS: MANOVA and ANOVA showed all 10 variables to be statistically significant (p < .002). Discriminant analysis correctly assigned 98.7% of the normal sperm heads to the NL group and 99.0% of sperm with acrosomal deficiency to the AD group. The percent acrosome and acrosomal area were determined to be the 2 most influential variables. ROC analysis identified a cutoff of 3.6 mu2 for acrosomal area as having the highest sensitivity and specificity (99.7% and 88.0%, respectively). Similarly, a cutoff of 44% for percent acrosome gave a sensitivity of 92.3% and a specificity of 88.7%. The coefficient of variation (CV) for each of the 10 variables determined from 20 day-to-day replicates of a normal semen smear ranged from 2.6% to 8.4%. CONCLUSION: Computerized image analysis is able to define a reference range for sperm head area, percent acrosome, and acrosomal area that may be used to differentiate normal form abnormal sperm heads. Maximum and minimum Ferret's diameters measure sperm head length and width, respectively. Mean maximum Ferret's diameter, minimum Ferret's diameter, and maximum-minimum Ferret's diameter ratio correspond closely to the WHO (1987) midpoint for normal sperm head length, width, and length-width ratio. The average percent acrosome of normal sperm heads determined by morphometry closely correlate to the WHO (1992) and Kruger (1988) midpoints for percent acrosome.

Acrosome↗

Distinct physiological mechanisms underlie altered glycinergic synaptic transmission in the murine mutants spastic, spasmodic, and oscillator.

Spastic (spa), spasmodic (spd), and oscillator (ot) mice have naturally occurring glycine receptor (GlyR) mutations, which manifest as motor deficits and an exaggerated "startle response." Using whole-cell recording in hypoglossal motoneurons, we compared the physiological mechanisms by which each mutation alters GlyR function. Mean glycinergic miniature IPSC (mIPSC) amplitude and frequency were dramatically reduced (>50%) compared with controls for each mutant. mIPSC decay times were unchanged in spa/spa (4.5 +/- 0.3 vs 4.7 +/- 0.2 ms), reduced in spd/spd (2.7 +/- 0.2 vs 4.7 +/- 0.2 ms), and increased in ot/ot (12.3 +/- 1.2 vs 4.8 +/- 0.2 ms). Thus, in spastic, GlyRs are functionally normal but reduced in number, whereas in spasmodic, GlyR kinetics is faster. The oscillator mutation results in complete absence of alpha1-containing GlyRs; however, some non-alpha1-containing GlyRs persist at synapses. Fluctuation analysis of membrane current, induced by glycine application to outside-out patches, showed that mean single-channel conductance was increased in spa/spa (64.2 +/- 4.9 vs 36.1 +/- 1.4 pS), but unchanged in spd/spd (32.4 +/- 2.1 vs 35.3 +/- 2.1 pS). GlyR-mediated whole-cell currents in spa/spa exhibited increased picrotoxin sensitivity (27 vs 71% block for 100 microM), indicating alpha1 homomeric GlyR expression. The picrotoxin sensitivity of evoked glycinergic IPSCs and conductance of synaptic GlyRs, as determined by nonstationary variance analysis, were identical for spa/spa and controls. Together, these findings show the three mutations disrupt GlyR-mediated inhibition via different physiological mechanisms, and the spastic mutation results in "compensatory" alpha1 homomeric GlyRs at extrasynaptic loci.

6-Cyano-7-nitroquinoxaline-2,3-dione↗

A randomized trial of endoscopic drainage methods for inoperable malignant strictures of the common bile duct.

BACKGROUND: Although metallic stents remain patent longer than plastic stents, the optimal palliation of inoperable malignant biliary strictures remains controversial because of the high cost of metallic stents and short patient survival. METHODS: A total of 101 patients (mean age 72.5+/-12.9 years) with malignant strictures of the common bile duct were included in this study, after three exclusions for technical failure (n = 3) and one for noncompliance with study design. The etiology of the strictures included pancreatic cancer (65), cholangiocarcinoma (21), ampullary tumor (3), and metastatic lymph nodes (12). Patients were randomized to receive either an 11.5F polyethylene stent to be exchanged in case of dysfunction (group 1, n = 33), an 11.5F stent to be exchanged every 3 months (group 2, n = 34), or a self-expanding metallic Wallstent (group 3, n = 34). RESULTS: Endoscopic procedures were successful (including complete relief of jaundice) in 97.1 % of cases. Procedure-related morbidity was 11.9%, and mortality was 2.9%. Bilirubinemia after 48 hours (37.2%+/-21.7% decrease from the preoperative level) did not differ between groups. Patients were followed for a mean of 166 days (median 143, range 0 to 596 days). Overall survivals were not different between groups, but complication-free survival for groups 2 and 3 was longer than that of group 1 (p < 0.05). Cumulated hospital days were 7.4+/-1.5, 10.6+/-1.7, and 5.5+/-1.4 (groups 1, 2, and 3, respectively) (p < 0.05; analysis of variance). Cost analysis showed that metallic stents were advantageous in patients surviving more than 6 months, whereas a plastic stent was advantageous in patients surviving 6 months or less. CONCLUSIONS: Metallic stents and plastic stents exchanged every 3 months are valuable alternatives for increasing complication-free survival in patients with malignant strictures of the common bile duct. Metal stents are advantageous in patients with the longest life expectancy.

Adult↗

Factors that affect the adhesion of two irreversible hydrocolloid materials to two custom tray materials.

STATEMENT OF PROBLEM: Little evidence is available on the length of time that adhesive should be allowed to dry before irreversible hydrocolloid impression making. PURPOSE: This study investigated the effect of adhesive drying times on the bond strengths of 2 irreversible hydrocolloid impression materials to 2 "custom" tray materials. MATERIAL AND METHODS: A total of 1,632 specimens were tested: 816 in tensile tests and 816 in tests of the shear bond strength (megapascals) of 2 irreversible hydrocolloid impression materials to an autopolymerizing and a visible light-polymerizing acrylic resin tray material. In the first part of the investigation, a single coat of adhesive was applied to specimen plates that simulated the custom impression tray surface; in the second part, a second coat of adhesive was applied after the irreversible hydrocolloid was removed, and the effect of this second coating on bond strength was examined. In both parts, the adhesive was allowed to dry for a range of times (0 to 8 minutes at 30-second intervals, for a total of 17 time periods) before the addition of the impression material. The specimen plates were placed in a humidor and separated in a universal testing machine operated at a crosshead speed of 100 mm/min with 0- to 5-kN load cell. Data from each of the 1,632 specimens were collected and evaluated with analysis of variance, regression analysis, and t tests (P<.05). RESULTS: Significant differences in mean bond strengths were found between specimens with a 4-minute adhesive drying time (0.179 MPa tensile, 0.068 MPa shear) and specimens with a 0-minute drying time (0.065 MPa tensile, 0.015 MPa shear). Any period over 4 minutes produced no significant difference. The mean bond strengths of the single-coated specimens were 0.179 MPa (tensile) and 0.076 MPa (shear). These values were significantly greater than those for specimens with a second adhesive layer (0.136 MPa tensile, 0.035 MPa shear) over all time periods. Mean tensile bond strengths (0.158 MPa) were consistently higher than shear bond strengths (0.056 MPa) for all combinations of tray material, adhesive application, and time. CONCLUSION: Within the limitations of this study, the results suggest that adhesive applied to the autopolymerized and light-polymerized custom tray materials tested should be allowed to dry for at least 4 minutes before irreversible hydrocolloid is applied. Better results were obtained when the adhesive layer from a failed irreversible hydrocolloid impression was removed and replaced rather than overlaid with an additional adhesive coating.

Acrylic Resins↗

Genetic differentiation of the marbled white butterfly, Melanargia galathea, accounts for glacial distribution patterns and postglacial range expansion in southeastern Europe.

Isolation of Mediterranean species in the southern European peninsulas during the cold glacial phases often resulted in differentiation of several genetic lineages confined to the respective peninsulas. However, whilst there is good genetic evidence for multiple refugia in Iberia, there are only limited data available for the Balkans. Therefore, we wish to examine the hypothesis of a strong genetic structuring within southeastern Europe for the existence of multiple Balkan differentiation centres and/or several leading edges. As a model we use the marbled white butterfly, Melanargia galathea. We studied 18 allozyme loci of 564 individuals from 16 populations distributed over a large part of southeastern Europe. The single populations showed moderately high genetic diversity and no northward decline of genetic diversity was detected. The overall genetic differentiation between populations was considerable (F(ST) 7.0%). Cluster analysis discriminated three genetic groups: (i) a western flank in the former Yugoslavia, parts of eastern Austria and Hungary; (ii) an eastern flank with populations from Bulgaria and Romania (south of the southern Carpathians and eastern Carpathians); and (iii) the eastern Carpathian Basin. Hierarchical variance analysis distributed 53% of the variance among populations between these three groups. One sample from the Greek-Bulgarian border clustered within the eastern flank, but showed some tendency towards the eastern Carpathian Basin populations. Two populations from Carinthia clustered together with the eastern Carpathian Basin ones and a population from Styria showed an intermediate genetic composition between the three groups. Most probably, the eastern and the western flank groups are due to postglacial range expansion from the northeastern and the northwestern edges of the glacial differentiation centre (so-called leading edges). The eastern Carpathian Basin group may have resulted from postglacial expansion from northern Greece through valley systems of the central Balkan peninsula, maybe even expanding westwards north of the Balkan mountains reaching some parts of eastern Austria (e.g. Carinthia). Therefore, the Balkanic refugium of M. galathea may or may not have been continuous along the coastal areas of the Mediterranean, but must have been strongly genetically structured.

Animal Migration↗

Flow-cytometric analysis of lymphocyte subsets and mCD14 expression in patients with various periodontitis categories.

BACKGROUND: Membrane-bound CD14 (mCD14) is expressed mainly on circulating monocytes and tissue macrophages. It is one of the receptors, which act at the recognition of lipopolysaccharides by host cells. Periodontopathic bacteria result in activation of cellular and humoral immune responses. AIM: The aim of the present study was to analyze the peripheral blood mCD14 concentrations as well as cell surface markers of lymphocyte subsets in periodontitis patients of various categories. MATERIALS AND METHODS: Peripheral blood samples were obtained from 22 early onset periodontitis (EOP), 10 adult periodontitis (AP) patients and 13 systemically and periodontally healthy control subjects. Three-color flow cytometry and a panel of relevant monoclonal antibodies were used to determine the percent expression of various cell surface markers on peripheral blood mononuclear cells (PBMCs). The results were tested statistically by one-way variance analysis and Newman Keuls test. RESULTS: No significant difference was observed between the study groups with regard to the relative counts of B-cells, T-cells, T-helper, T-cytotoxic/suppressor, activated T-cells and natural killer cells. EOP patients expressed significantly lower level of interleukin-2 receptor (IL-2R) when compared with AP patients (6.08% and 19.3% respectively) (p<0.05). The level of mCD14 in EOP patients (7.18%) was lower than that of AP patients (9.3%) and the control subjects (9.2%), but the differences were not statistically significant. CONCLUSIONS: The low level of IL-2R in the EOP group may be interpreted as an insufficient responsiveness to the periodontopathogens, which may be ultimately related with the more severe tissue destruction. Though not significant, the reduced expression of mCD14 in EOP group may also be related with the immune system deficiencies in these patients.

Adolescent↗

Applications of statistical equivalence to newborn EEG recordings.

Epochs were selected from sleep EEGs of newborns during both quiet and REM phases. A first order parameter analysis was done in order to test the homogeneity (run test and one way variance analysis) of the data within the epochs, follwed by a study of spectral equivalence between epochs. Comparisons were made between average spectra in the frequency range 0.5--4 c/sec; and between their band-by-band components, to test the feasibility of automatic classification of sleep stages by means of frequency analysis. On the basis of the statistical parameters we used, spectral analysis appears to be of limited value for the purpose of automatic classification of newborn EEG records; due to a lack of complete homogeneity of the spectra within each sleep state, it is not possible to identify a characteristic spectrum for active sleep and quiet sleep.

Electroencephalography↗

Variability of consecutive in vivo MR flow measurements in the main portal vein.

OBJECTIVE: The variability of consecutive cine phase-contrast MR flow measurements could significantly affect their use for clinical decisions, especially during provocative testing. The purposes of this study were to determine the normal variability of flow and consecutive flow measurements in the main portal vein on MR images and to determine how intraobserver variability, interobserver variability, and MR imager variability affect these measurements. SUBJECTS AND METHODS: MR flow measurements were acquired four consecutive times at the same location in the main portal vein of 12 subjects and three consecutive times at the same location in a nonpulsatile vessel model. All acquisitions were completed within 10 min. All main portal vein MR data sets were evaluated manually in a blinded review by two independent observers during three separate sessions spaced a mean of 4.5 weeks apart. Flow model data sets were evaluated during a single session by one observer. Variabilities were subsequently calculated by a components-of-variance analysis and by the coefficient of variation (SD/mean x 100). RESULTS: Of the total variance, 90% was due to flow variability among subjects (intersubject), 6% to flow variability within one subject (intrasubject), 2% to intraobserver variability, and 2% to interobserver variability. The coefficient of variation of consecutive MR portal vein flow measurements within a single subject was 11% +/- 5% (range, 3-23%). Intra- and interobserver variabilities were 5% +/- 2% (range, 1-11%) and 4% +/- 4% (range, 0-17%), respectively. MR imager variability was 1% +/- 1% (range, 0-2%). CONCLUSION: The mean variability of consecutive cine phase-contrast MR flow measurements in the main portal vein is 11% +/- 5% and could affect research and clinical protocols that employ this technique.

Adult↗

Analysis of joint mobility patterns among preschool children.

CONTEXT AND OBJECTIVE: Standardization of normal joint mobility criteria is complex, especially for preschool children, for whom differentiation from hypermobility (JH) is even more difficult. This study aimed to investigate joint mobility of the fifth finger, wrist, elbow, knee and trunk among preschool children, estimate the incidence of JH and evaluate the effect of gender and age and the applicability of standard criteria for identifying JH among preschool children. DESIGN AND SETTING: Cross-sectional descriptive and quantitative study, at São José do Rio Preto medical school. METHODS: 1,120 healthy children (534 boys, 47.7%; 586 girls, 52.3%; age range: 4-7 years) were evaluated using Beighton scores. Passive extension of fifth finger (> 90 degrees), passive apposition of thumb to forearm, active extension of elbow and knee (> 10 degrees) and anterior trunk flexion placing flat hand on ground were assessed. One point was scored for each positive result (maximum: 9). Scores > 4 were considered to be JH. Students t test and variance analysis were used for statistical analysis. RESULTS: JH was observed in 80% of wrists, 53.3% of fifth fingers, 36.6% of elbows, 14% of trunks and 12.5% of knees. Scores > 4 were found for 64.6% of the children. Females had higher angular values. Lower scores were associated with greater age. CONCLUSIONS: JH is a common condition among preschool children and currently available methods are inadequate. New parameters and criteria should be developed for identifying JH among these children.

Age Factors↗

[Bony malformations of the cranio-vertebral junction and its clinical relevance (author's transl)].

A statistical analysis is performed in 86 cases suffering from osseous malformation of the cranio-vertebral junction. The material consists of 71 cases with basilar impression, 8 cases with hypoplasia or absence of the odontoid process, and 7 cases with a congenital atlanto-epistropheal dislocation. The patients are clinically asymptomatic in 23 cases, and are marked by a para-respectively tetraparesis in 28 cases, by bulbar-pontine-cerebellar disorders in 24 cases, and by syringomyelia in 11 cases. A control group is included consisting of 30 cases without neurological symptoms and with a normal radiological finding of the cranio-vertebral region. The following measured values are taken in consideration to perform a statistical calculation using the simple variance analysis: The height of the odontoid process above of McGregor's line, the distance between the back of the odontoid process and the inner limit of the arch of C1, and, concerning the groups with hypoplasia of the odontoid process process and with atlanto-axial dislocation, the narrowing of the spinal canal at the level of C1 dependent on movements of the head. The measured values are referred to the different clinical syndromes and are described and divided according to its statistical significance related to the clinical groups.

Adolescent↗