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PubMed1982

[Effect of temperature on the results of the antibiotic sensitivity test performed by the diffusion method in fish pathology].

The sensitivity disk method is currently used in fish pathology to assess the efficacy of antimicrobial drugs. However, it is generally performed at temperatures lower than 37 degrees C, at which standard procedures were recommended by WHO. In order to check up the reliability of the results, selected strains and antibiotic substances were at once studied at 37 degrees C and 22 degrees C. In the last case, two readings of the zones of inhibition were done, after 24 and 48 h of incubation. Minimal inhibitory concentrations (MIC) had been determined using an agar-plate dilution method. Each association drug-bacterial strain provided three samplings of 30 measures which were compared by variance analysis and mean comparison tests. Variances did not differ, except with chloramphenicol and tetracyclines. But the mean values of the diameters significantly differed according to the incubation temperature. The variations could reach 7 to 8 mm, in any way. So, it appears that the disk method fails to allow any quantitative interpretation when performed at 22 degrees C. Consequences in diagnostic of fish diseases are stressed.

Animals↗
PubMed1994

[Seminal changes in unilateral cryptorchism: course after orchidopexy. Experimental study].

The present study was conducted to determine the reversibility of the seminal alterations following experimental unilateral cryptorchidism in relation to the time orchiopexy is performed. Two groups of 45 Wistar rats were subjected to mechanical unilateral cryptorchidism followed by prepubertal, early and late orchiopexy, respectively. A third group of 45 animals was subjected to a sham operation. We analyzed the semen obtained separately from both epididymal tails of subgroups of 15 animals at 2.5, 5 and 8 months for the number of spermatozoa, percentage of motile spermatozoa, survival time and the number of heads and tails of loose spermatozoa. The statistical analysis of the results by variance analysis showed that the significant reduction of the number of spermatozoa and the percentage of motile forms observed in the ex-cryptorchid testis at age 2.5 months in both groups of animals that were subjected to a testicular retention had been completely recovered at age 5 months. A significant reduction of the percentage of motile spermatozoa at age 2.5 months was observed in the contralateral testis of animals subjected to a longer period of retention. This alteration was also found normalized at age 5 months. In conclusion, experimentally, pre-pubertal orchiopexy preserves fertility at an adult age, regardless of the timing of the procedure.

Animals↗
PubMed1985

Detection and characterization of spatial pattern in chimaeric tissue.

The mosaic pattern of patches of crypts of Lieberkühn in chimaeric C57BL/6JLac (B6)----DDK mouse small intestine, demonstrated using Dolichos biflorus agglutinin as strain-specific marker, is quantitatively examined using the Greig-Smith analysis of variance. This analysis, widely used in ecological research, provides a method to detect and characterize pattern at various scales. The analysis demonstrates that B6 patches are non-randomly distributed at all scales examined. A consistent increase in the intensity of pattern at one particular scale over all replicate samples identifies 'clusters of clusters' which probably are territories of 'descendent' clones. The sizes of descendent clones, either in terms of numbers of patches or total numbers of crypts, are highly variable. A steady reduction in the strength of pattern from proximal to distal is found. The Greig-Smith analysis of variance provides a valuable method for the analysis of pattern in chimaeric tissue.

Analysis of Variance↗
PubMed1991

[Study on the estimation methods of genetic parameters with mixed family].

By theoretically supposing the male variance component be equal to the female variance component, a new method and an approximate estimation method of heritability are suggested on the basis of decomposing the expected mean squares in variance analysis with mixed families. Seven estimation methods of heritability are compared by an actual estimation example. The results indicate that the difference of the estimation value between full-sib analysis method and the method suggested in this paper is the smallest and the standard error of estimated heritability by the latter method is the smallest among the standard error of estimated heritability by the latter method is the smallest among the seven methods. Also the approximate method is effective. For all methods, the more disequilibrium of the data, the bigger difference of the estimate value by those methods. The new method can be used when the difference of variance components between male and female is relatively large with full-sib analysis in actual estimation. Moreover, the new method is easily calculated because the two-way classification data was analyzed by one-way classification variance analysis and the average relationship coefficient among mixed families may not need to be calculated.

Analysis of Variance↗
PubMedDate not supplied

Quantitative assessment of enamel hypomineralization by KaVo DIAGNOdent at different sites on first permanent molars of children in China.

PURPOSE: The purpose of this study was to identify the most caries-susceptible site of pits and fissures on first permanent molars by quantitative evaluation of the mineralization in both caries-active and caries-free children, and to provide helpful information for cost-effective, targeted prevention. METHODS: Eighty-four caries-free and 85 caries-active children were selected from 800 6- to 7-year-old children with fully erupted first permanent molars. Hypomineralization of the central fossa (CF) and lingual pit (LP) of the maxillary or buccal pit (BP) of mandibular first permanent molars were evaluated by KaVo DIAGNOdent. Statistical analysis included grouped t test and single-factor variance analysis and paired comparison. RESULTS: CF of mandibular first permanent molars had significantly greater hypomineralization than other sites. The hypomineralization of the maxillary CF is more severe than that of LP. The extent of the hypomineralization of each site at the first permanent molar in caries-active children was significantly higher than that in caries-free children. CONCLUSIONS: Central fossae of first mandibular molars are the most hypomineralized sites in both caries-free and caries-active groups. The results suggest that preventive interventions should be targeted at the CF of mandibular molars with special concern given to the caries-active population.

Analysis of Variance↗
PubMed1975

[Statistical analysis of the activity of loxapine and thioridazine in a double-blind study].

49 patients have been treated for 12 weeks with loxapine and thioridazine in a double-blind study. The evaluation was carried out with a covariance analysis with B.P.R.S. and NOSIE as bases and a variance analysis concerning the general clinical improvement. With 36 schizophrenics, the two treatments have shown significant and similar general improvement as early as the second week, and this in particular with all the factors and most of the items of the B.P.R.S. with 13 psychotic not schizophrenic patients, the covariance analysis showed that the results (improvement of all the factors, with most of the items and in the total score of the B.P.R.S.), while comparable, were slightly in favour of loxapine for the item "disorientation", for "disturbance of thought", and "excitement-disorientation", for the final score of B.P.R.S., for the general and clinical improvement and for the alteration of the initial degree of severity. The analysis of the NOSIE showed a significant improvement which is similar for both treatments.

Analysis of Variance↗
PubMed2001

Lipoprotein (a) behaviour in patients with hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) is a malignancy representing in Europe the 3-5% of all malignant tumors. Metabolic pathway of Lipoprotein(a) [Lp(a)] is influenced by various cytokines delivered during inflammatory and neoplastic diseases. Liver seems to be the main site of Lp(a) synthesis. METHODS: A group of patients affected by HCC was studied in order to evaluate the changes in serum Lp(a) levels and their significance. PARTICIPANTS: 40 patients (25 males and 15 females) affected by primary HCC and 25 control healthy subjects (12 males and 13 females). In HCC patients we evaluated the following serological parameters: Lp(a), total cholesterol (TC), LDL-Cholesterol (LDL-C), HDL-Cholesterol (HDL-C), triglycerides (TG), albumin, (pseudo)cholinesterase (CHE), aspartate amino-transpeptidase (AST), alanine amino-transpeptidase (ALT), gamma-glutamyl transpeptidase (g-GT), alkaline phosphatase (ALP), ferritin, alpha fetoprotein, partial thromboplastin time (PTT), Quick time, prothrombinic activity (PA) and fibrinogen. Statistical analysis of the data obtained was performed using the variance analysis (ANOVA method) and Student's OtO for non-paired data test. For Lp(a), Wilcoxon's non parametric test was used. The correlations between examined parameters were performed by Pearson's correlation test. RESULTS: In patients with HCC, mean serum TC, LDL-C TG and Lp(a) levels were significantly lower than in controls. HDL-C did not show a statistically significant difference between the two groups studied. Furthermore, we found a positive correlation between: Lp(a) and CHE, Lp(a) and albumin, CHE and LDL-C; while a negative correlation has been found between: Lp(a) and alpha-fetoprotein, Lp(a) and ferritin, CHE and alpha-fetoprotein. CONCLUSIONS: On the basis of the relationship with alfa fetoprotein and ferritin serum levels, Lp(a) seems to represent an indirect index of liver damage. Lp(a) is a risk factor for vascular diseases and seems to have an interesting role in the liver functions. We conclude that the evaluation of Lp(a) serum levels may contribute, among other markers, to a more complete evaluation of the liver function in patients with HCC suggesting a predictive role for this lipoprotein.

Aged↗
PubMed2006

[Development of an optimized formulation of flaxseed (Linum usitatissimum) mousse].

Taguchi method was applied to determine the maximum sensory quality of a functional flaxseed mousse desert ready to mix by minimizing the deviation from the target value. An orthogonal array (OA) experimental design that allows to analize simultaneously the influence of four independent variables (thermic process; carrageen/gelatine ratio; grated cocconut/cocconut flavour ratio; whipping time) with three tolerance level each was applied to evaluate the effects of these control factors. Performance measure analysis were carried out using standard analysis to calculate average effects of factor levels and variance analysis, in order to determine the optimum levels and significant contribution of the control factors. To determine the optimum conditions, Taguchi's "the large the better" formula was used. These turn out to be thermic process, 95 degrees C/90s; carrageen/gelatine, 0.54g/ 1.07g; grated cocconut/ cocconut flavour, 10.7g/4.23g; whipping time, 8 min. Sensory quality was determined using the composite scoring test and a trained sensory panel of 12 judges. Chemical composition of optimized flaxseed mousse turn out to be protein, 20%; total dietary fibre, 18%; carbohydrates, 26.7%. Omega 6/omega 3 ratio of 0.4 was considered good. Amount of flaxseed in optimized flaxseed mousse was enough to satisfy the 30% of recommended dietary allowance of linolénic acid. Shelf life data showed a good stability for this product as well a good consumer acceptability.

Adolescent↗
PubMed1977

[Effects of colchicine treatment on rat intestinal disaccharidase activities].

UNLABELLED: The changes in morphology and proliferation kinetics produced by colchicine in the intestinal mucosa are known. Contrarily, the functional changes have yet not been investigated systematically. The aim of this study is to investigate the effects of colchicine treatment on rat intestinal disaccharidase activities. MATERIAL AND METHODS: For the experiments male SPF-Wistar rats, body weight 180--200 g (supplied by Mus-Rattus AG, 8011 Brunnthal, FRG) were used. The animals were kept under constant conditions (6 rats per cage) and fed Altromin (Altromin Gmb H,Lage/Lippe), tap water ad libitum. Per day 6 animals of each test group were scarificed by cervical dislocation at defined time. About 3 cm of the intestine were removed 8--10 cm distally of the pylorus and cut longitudinally. After cautious cleaning the mucosa was detached using a scalpel. The thus obtained specimens of the mucosa were frozen at -- 20 degrees C in an air-tight humidity chamber and preserved there until further handling. For histological examination the correspondent parts of the intestine were fixed in 10% formol. From each specimen 4 different stainings were made (haematoxylin-eosin, Giemsa, PAS and Feulgen stain). Per test series 60--66 rats were used. The following doses of colchicine were applied: 1 X 1.0 mg/kg body weight, 1 X 0.5 mg/kg body weight, 5 X 0.1 mg/kg body weight within 24 hours. The single doses were dissolved in about 0.5 physiological saline and applied intraperitoneally. In each 6 rats per group the activities of the following diasccharidases were measured at 24 hours intervals from the 1st to 10th or 14th day: sucrase, maltase, lactase, and cellobiase. The enzyme activities were determined after the two-step method developed by DAHLQVIST (5,6) which can be used as micromethod. The ascertained enzyme activities were always related to the protein content. Protein determination was done after the method of Folin-Ciocalteu as modified by LOWRY et al. (14). The enzyme activities were expressed in international units per g protein (U/g protein). the results obtained were statistically ascertained by the non-parametric test after Kruskal-Wallis, variance analysis with linear contrasts after Scheffe as well as by double variance analyses (26).

Analysis of Variance↗
PubMed2001

Familial factors of blood pressure and adiposity covariation.

In the present study, we used the maximum likelihood approach as implemented by variance analysis and attempted to quantify genetic and environmental components of variance in systolic (SBP) and diastolic (DBP) blood pressure in 514 individuals who belonged to a total of 135 nuclear families of Chuvasha, Russia, ethnic origin. The extent to which these interindividual differences depend on age, gender, body mass index (BMI) and other anthropometric measurements was investigated. Major findings include the following. (1) The variation in both SBP and DBP was significantly affected by genetic factors (h(2)(SBP)=0.51+/-0.13, h(2)(DBP)=0.20+/-0.09), shared household environment, and age. These effects were stronger with respect to SBP, which also showed significant gender differences in baseline values and rate of SBP increase with age. (2) Genetic and common household factors, as well as undetected residual effects, were not completely independent. The respective 3 facets of correlation between SBP and DBP were significant: 0.66+/-0.10, 0.76+/-0.11, and 0.55+/-0.14. (3) SBP and DBP each showed significant phenotypic correlations with BMI and anthropometric factors. These correlations had a substantial genetic component but were not equal for SBP and DBP. SBP showed the highest genetic correlation with arm circumference (r(G)=0.63), whereas for DBP, this was found with hip skinfold (r(G=)0.88). (4) Bivariate heritability estimates, as well as adjustment of BP measurements for BMI and selected anthropometrics, indicated that DBP likely does not have independent genetic heritability. The residual genetic variance of adjusted SBP remained significant, although substantially lower in comparison with the nonadjusted h(2).

Adipose Tissue↗
PubMed1975

Genetic component in learning ability in bees.

Twenty-five bees, five from each of five hives, were trained to collect food at a table. When the bee reached the table, time was recorded for 12 visits. Then a blue and yellow pan was substituted for the original metal pan, and time and correct responses were recorded for 30 trips (discrimination phase). Finally, food was taken from the pan and extinction was recorded as incorrect responses for 20 visits. Variance analysis was carried out, and genetic variance was undetected for discrimination, but was detected for extinction. It is concluded that learning is very important for bees, so that any impairment in such ability affects colony survival.

Animals↗
PubMed2001

[Effect of latanoprost on ocular hemodynamics and contrast sensitivity].

BACKGROUND: Latanoprost effectively lowers intraocular pressure. Because ischemia has gained increasing importance in the pathogenesis of glaucoma, an antiglaucomatous drug should also be investigated with regard to the influence on ocular hemodynamics. METHODS: In a double masked, randomized, clinical trial, Latanoprost eye drops were administered to 15 volunteers once daily for 8 days and 15 further volunteers received placebo eye drops according to the same protocol. IOP, blood pressure, heart rate, ocular pulse amplitudes, pulse volume, pulsatile ocular blood flow and contrast sensitivity were measured before (1T0), 120 min after drop administration (1T120), after 7 days of therapy (8T0) and again 120 min after an acute administration (8T120). For statistical analysis a two-way variance-analysis and the t-test for paired samples were used. RESULTS: IOP was found to be statistically significantly different comparing both groups over the test period (p = 0.036). In Latanoprost-treated subjects the t-test revealed a significant drop in IOP between 1T0 and 8T0 (p = 0.009) and between 1T0 and 8T120 (p < 0.0001). All other above mentioned parameters remained constant. CONCLUSION: In Latanoprost-treated subjects, a significant drop in intraocular pressure was observed after 1 week. However, ocular perfusion and contrast sensitivity did not change during therapy. This might be due to an effective autoregulation in healthy volunteers.

Adult↗
PubMed1999

Small acoustic neuromas: monitoring the growth rate by MRI.

In a proportion of small acoustic neuroma patients, monitoring with magnetic resonance imaging shows no volumetric increase of tumour size over the years. The object of the study was to identify some indications for the clinical choice between immediate surgery (with the related risks) and watchful waiting. We performed a retrospective study of 47 non-surgically-treated patients affected by acoustic neuroma and monitored by gadolinium-enhanced MRI between January 1990 and February 1999. Six clinical variables (tumour size, sex, age, initial symptoms, ABR pattern and duration of the symptoms) were examined by univariate analysis. Chi-square test and variance analysis were performed to evaluate the statistical significance. In 30/47 (63.8%) cases, no growth was observed during the entire period of follow-up. In the remaining 17/47 (36.2%) patients, a volumetric increase was detected, most often within the first year of observation. The clinical factors examined did not significantly correlate with growth. Despite the relatively short period of observation, we believe that immediate surgery does not need to be considered mandatory for small acoustic neuromas, even in young patients. However the irregular behaviour of the tumour underlines the importance of monitoring with MRI at least once a year.

Adult↗
PubMed1975

Genetic and environmental influences on morphological characteristics.

Study has been made of 37 anthropometric measurements in a socially selected sample of 125 Belgian families, comprising parents and adult children. The parent-child and mid-parent-child correlation coefficients indicate that the extent of genetic determination varies considerably from one measurement to another, being greatest in the longitudinal body measurements, least in the circumferences involving soft tissues and in measures of the nose and mouth. Further analysis of the intrafamilial correlation, and variance analysis by the method of Fisher and Gray (1937), shows that neither dominant nor X-linked loci exert any appreciable effects.

Adolescent↗
PubMed2005

Caries experience in the primary dentition among French 6-year-olds between 1991 and 2000.

BACKGROUND: There are few national caries preventive policies for children in France. Various surveys suggest that in the late 1980s, oral health of the 6-year olds in France was poorer than in those of other European countries. In Val de Marne (a Department just east of Paris) a public dental service was established in 1991. A programme to inform preschool staff about dental diseases was commenced and volunteers brought oral health information to parents and health professionals. Periodical monitoring of primary tooth caries of 6-year olds was planned. AIM: The aim of the study was to evaluate changes in primary tooth caries in 6-year olds over the 10 years of the programme. METHODS: Participating 6-year olds, randomly selected, were examined in schools by dentists. Clinical data were collected (WHO criteria). Sociodemographic data were collected through questionnaire. Statistical analysis involved comparison of mean values, variance analysis and chi-square test for categorical variables. RESULTS: The proportions of children with caries experience were, 38.9%, 30.6% and 22.2% in 1991, 1995 and 2000 respectively (P < 0.01). The dft index decreased from 1.74 to 1.39 and 1.05 respectively. About 75% of children with dental caries remained untreated. Children of non-European native parents or belonging to low socioeconomic families remained those most affected by dental caries in 2000. CONCLUSION: Dental caries in 6-year olds improved between 1991 and 2000 in Val de Marne but caries remained a socially inequitable disease. Most children did not have access to dental care. The situation requires changes to the dental care provision system.

Age Factors↗
PubMed2004

[Educational program in schistosomiasis: a model for a methodological approach].

OBJECTIVE: Lack of knowledge is one of the factors responsible for the persistence of infectious diseases in Brazil. This study had the objective of developing, implementing and evaluating a low-cost educational program using schistosomiasis patients as a model. METHODS: This was a descriptive study developed using a population of healthy people (group 1) and schistosomiasis patients (groups 2 and 3), with 20 individuals in each group. Teaching material (illustrated manual and album of leaflets) and a questionnaire consisting of 17 questions to evaluate the groups' knowledge were devised. The questionnaire was applied to groups 1 and 2 before and to group 3 after the educational program. The variables studied were the educational program, level of schooling, age, clinical form of schistosomiasis, symptoms, and the subject's performance when answering the questionnaire. For the statistical analysis, Fisher's exact test and variance analysis with one fixed factor were utilized. RESULTS: The educational program was evaluated in the form of four topics: cycle, clinical presentation, treatment and prevention of the disease. The median number of correct responses to the questionnaire was higher for group 3 than for groups 1 and 2, for all the topics dealt with. This median was also higher for group 2 than for group 1, for all topics except for the item "prevention". CONCLUSIONS: The educational process applied was efficient and improved the knowledge of the disease. It may provide an effective low-cost methodological model that can also be applied to combating other endemic diseases.

Adult↗
PubMed2003

Lung mechanics and high-resolution computed tomography of the chest in very low birth weight premature infants.

CONTEXT: Premature infant lung development may be affected by lung injuries during the first few weeks of life. Lung injuries have been associated with changes in lung mechanics. OBJECTIVE: To evaluate an association between lung mechanics and lung structural alterations in very low birth weight infants (birth weight less than 1500 g). DESIGN: A cross-sectional evaluation of pulmonary mechanics (lung compliance and lung resistance) and high resolution computed tomography of the chest at the time of discharge, in 86 very low birth weight infants born at Instituto Fernandes Figueira, a tertiary public healthcare institution in Rio de Janeiro, Brazil. Lung compliance and resistance were measured during quiet sleep. High resolution computed tomography was performed using Pro Speed-S equipment. MAIN MEASUREMENTS: Statistical analysis was performed by means of variance analysis (ANOVA/Kruskal Wallis). The significance level was set at 0.05. RESULTS: Abnormal values for both lung compliance and lung resistance were found in 34 babies (43%), whereas 20 (23.3%) had normal values for both lung compliance and lung resistance. The mean lung compliance and lung resistance for the group were respectively 1.30 ml/cm H2O/kg and 63.7 cm H2O/l/s. Lung alterations were found via high-resolution computed tomography in 62 (72%) infants. Most infants showed more than one abnormality, and these were described as ground glass opacity, parenchymal bands, atelectasis and bubble/cyst. The mean compliance values for infants with normal (1.49 ml/cm H2O/kg) high resolution computed tomography, 1 or 2 abnormalities (1.31 ml/cm H2O/kg) and 3 or more abnormalities (1.16 ml/cm H2O/kg) were significantly different (p=0.015). Our data were insufficient to find any association between lung resistance and the number of alterations via high-resolution computed tomography. CONCLUSION: The results show high prevalence of lung functional and tomographic abnormalities in asymptomatic very low birth weight infants at the time of discharge. They also show an association between lung morphological and functional abnormalities.

Airway Resistance↗
PubMedDate not supplied

[Strategies for teaching self-examination of the breast to women in reproductive age].

OBJECTIVE: To develop an effective strategy to inform Mexican women between 12 and 47 years of age about breast cancer (BC) and train them to perform breast self-examination (BSE). MATERIAL AND METHODS: Between April, 1996 and July, 1998, two different strategies to teach BSE were designed and evaluated in Cuernavaca, State of Morelos, Mexico. These strategies included teaching materials and were based on opinions of women participating in the first stage of this study. Both strategies consisted of the presentation of a leaflet and a video. The first strategy was delivered by a public health nurse in charge of leading the session. The second one was presented by a BC survivor. This second strategy included slides and silicon breast models. These two strategies were then compared to a third one, consisting of a primary care nurse handling out a leaflet and showing a video, based on Health Secretariat's guidelines. In total, 149 women were trained. They were randomly assigned to any one of these three strategies. The effectiveness of the teaching strategies was determined by assessing the changes in the women's knowledge of BC and BSE, as well as in their ability to identify the largest number of lumps on a natural size silicon breast, before and after training. Statistical analysis included Student's t test, variance analysis, McNemar's chi 2, Pearson's chi 2, and multiple linear regression. RESULTS: With all three strategies, there was an increase of approximately 30% in women's knowledge of BC and BSE as well as in their ability to detect lumps. Although at the beginning of the training only one out of every 20 women were able to identify more than three lumps in the silicon model, by the end between 3 and 4 of every 10 women were able to do this, with values of p < 0.05. Some factors determine women's learning of both BSE and information about BC as well as their ability to identify lumps. CONCLUSIONS: Teaching BSE with any of the strategies evaluated could be included in an integral program to educate Mexican women on breast cancer prevention and early detection. The appropriate and monthly practice of BSE is linked both to a decrease in the amount of time elapsing between the identification of suspect signs and the demand for medical care, such as requesting a clinical breast examination, which entails identifying small tumors when BC is present.

Adolescent↗