Rapid spot test analysis for the detection of urotropine in pharmaceutical preparations

The widespread falsification and/or adulteration of commercially available pharmaceutical preparations call for reliable methods of drug identification, preferably through selective and rapid sorting color tests that could be undertaken with minimum equipment remote from laboratory facilities. The present work deals with a convenient adaptation and refinement of a spot test devised by Feigl (1966) for urotropine, based on the hydrolytic cleavage of that substance in the presence of sulfuric acid, splitting out formaldehyde which is identified by its color reaction with chromotropic acid. A simple emergency kit was developed for the quick, efficient, inexpensive and easy performance of urotropine tests by semiskilled personnel even in the drugstore laboratory (or office) as well as in a mobile screening operation. It is shown that when the reagents are added according to the recommended sequence a self-heating system is generated, increasing substantially the reactions' rates and the test sensitivity as well. The identification limit found was 25 mug of urotropine, for both solid and liquid samples. The possible interference of 84 substances/materials was investigated. Interference was noted only for methylene blue, acriflavine, Ponceau Red, Bordeaux Red (these dyes are often included in urotropine dosage forms), pyramidone, dipyrone, quinine and tetracycline. A simple procedure for removing most of the interferences is described. Data for 8 commercial dosage forms and results obtained from their analysis are presented.

Biocompatibility of gutta-percha solvents using in vitro mammalian test-system

Objectives. Taking into consideration that DNA damage and cellular death play important roles during carcinogenesis, the purpose of the present study was to evaluate in vitro genotoxic or cytotoxic effects of chloroform and eucalyptol by single cell gel (comet) assay and trypan blue exclusion test, respectively.Study design. Chloroform and eucalyptol were exposed to Chinese hamster ovary cells in culture directly for 3 hours at 37 degrees C at final concentrations ranging from 1.25 to 10 mu L/mL. The negative control group was treated with vehicle control (phosphate-buffered solution), and the positive control group was treated with methyl metasulfonate (MMS, at 1 mu g/mL concentration). All data were analyzed by the Kruskal-Wallis nonparametric test followed by the Dunn test.Results. The results showed that both gutta-percha solvents were cytotoxic at concentrations of 2.5, 5, and 10 mu L/mL (P < .05). on the other hand, both solvents did not induce DNA breakage at 1.25 mu L/mL concentration.Conclusions. These results suggest that both chloroform or eucalyptol are strong cytotoxicants, but they may not be a factor that increases the level of DNA lesions in mammalian cells.

The effects of anxiety on visual search, movement kinematics, and performance in table tennis: A test of Eysenck and Calvo's processing efficiency theory

Processing efficiency theory predicts that anxiety reduces the processing capacity of working memory and has detrimental effects on performance. When tasks place little demand on working memory, the negative effects of anxiety can be avoided by increasing effort. Although performance efficiency decreases, there is no change in performance effectiveness. When tasks impose a heavy demand on working memory, however, anxiety leads to decrements in efficiency and effectiveness. These presumptions were tested using a modified table tennis task that placed low (LWM) and high (HWM) demands on working memory. Cognitive anxiety was manipulated through a competitive ranking structure and prize money. Participants' accuracy in hitting concentric circle targets in predetermined sequences was taken as a measure of performance effectiveness, while probe reaction time (PRT), perceived mental effort (RSME), visual search data, and arm kinematics were recorded as measures of efficiency. Anxiety had a negative effect on performance effectiveness in both LWM and HWM tasks. There was an increase in frequency of gaze and in PRT and RSME values in both tasks under high vs. low anxiety conditions, implying decrements in performance efficiency. However, participants spent more time tracking the ball in the HWM task and employed a shorter tau margin when anxious. Although anxiety impaired performance effectiveness and efficiency, decrements in efficiency were more pronounced in the HWM task than in the LWM task, providing support for processing efficiency theory.

Test systems and mathematical models for transmission network expansion planning

The data of four networks that can be used in carrying out comparative studies with methods for transmission network expansion planning are given. These networks are of various types and different levels of complexity. The main mathematical formulations used in transmission expansion studies-transportation models, hybrid models, DC power flow models, and disjunctive models are also summarised and compared. The main algorithm families are reviewed-both analytical, combinatorial and heuristic approaches. Optimal solutions are not yet known for some of the four networks when more accurate models (e.g. The DC model) are used to represent the power flow equations-the state of the art with regard to this is also summarised. This should serve as a challenge to authors searching for new, more efficient methods.

Observational study on efficacy of negative expiratory pressure test proposed as screening for obstructive sleep apnea syndrome among commercial interstate bus drivers - protocol study

Background: Obstructive sleep apnea (OSA) is a respiratory disease characterized by the collapse of the extrathoracic airway and has important social implications related to accidents and cardiovascular risk. The main objective of the present study was to investigate whether the drop in expiratory flow and the volume expired in 0.2 s during the application of negative expiratory pressure (NEP) are associated with the presence and severity of OSA in a population of professional interstate bus drivers who travel medium and long distances.Methods/Design: An observational, analytic study will be carried out involving adult male subjects of an interstate bus company. Those who agree to participate will undergo a detailed patient history, physical examination involving determination of blood pressure, anthropometric data, circumference measurements (hips, waist and neck), tonsils and Mallampati index. Moreover, specific questionnaires addressing sleep apnea and excessive daytime sleepiness will be administered. Data acquisition will be completely anonymous. Following the medical examination, the participants will perform a spirometry, NEP test and standard overnight polysomnography. The NEP test is performed through the administration of negative pressure at the mouth during expiration. This is a practical test performed while awake and requires little cooperation from the subject. In the absence of expiratory flow limitation, the increase in the pressure gradient between the alveoli and open upper airway caused by NEP results in an increase in expiratory flow.Discussion: Despite the abundance of scientific evidence, OSA is still underdiagnosed in the general population. In addition, diagnostic procedures are expensive, and predictive criteria are still unsatisfactory. Because increased upper airway collapsibility is one of the main determinants of OSA, the response to the application of NEP could be a predictor of this disorder. With the enrollment of this study protocol, the expectation is to encounter predictive NEP values for different degrees of OSA in order to contribute toward an early diagnosis of this condition and reduce its impact and complications among commercial interstate bus drivers.

Probability distribution models for daily rainfall data for an interior station of Brazil

Two stochastic models have been fitted to daily rainfall data for an interior station of Brazil. Of these two models, the results show a better fit to describe the data, by truncated negative probability model in comparison with Markov chain probability model. Kolmogorov-Smirnov test is applied for significance for these models. © 1983 Springer-Verlag.

Indirect fluorescent test for detection of anti-Paracoccidioides brasiliensis antibodies using coated bentonite particles as antigen

An indirect fluorescent test was developed for detecting antibodies to Paracoccidioides brasiliensis using bentonite particles as antigen (Bent-IF). The bentonite particles were coated with P. brasiliensis polysaccharide antigen and tested with sera from paracoccidioidomycosis patients (36 sera), normal blood donors (32 sera) and patients with non-mycotic diseases (29 sera). The titres given by the positive sera were compared with those of complement fixation (CF), immunodiffusion (ID) and immunofluorescent test using yeast forms of the fungus as antigen (conventional-IF). All normal blood donors' sera gave a negative Bent-IF, conventional-IF, ID and CF tests. All paracoccidioidomycosis sera were reactive in conventional-IF and gave concordant results in Bent-IF. There was no correlation between CF and Bent-IF titres. 27·6% of sera from patients with non-mycotic diseases gave weak titres in both IF-tests. The present data indicate that the Bent-IF is a sensitive and simple serodiagnostic technique comparable with the conventional P. brasiliensis antibody test. © 1983.

Serology of paracoccidioidomycosis - I. Evaluation of the indirect immunofluorescent test

The purposes of the present work were: i) to study the positivity indices and compare titers obtained with the indirect immunofluorescence (II), tube precipitation (TP), complement fixation (CF) and double immunodiffusion on agar gel (ID) tests in the sera of 196 patients with paracoccidioidomycosis before treatment, and ii) to compare the initial titers of II with those obtained 1 year or more after treatment. II was the most sensitive serologic reaction (85.2%), and the positivity indices for CF, ID and TP were 67.7%, 66.0% and 50.0%, respectively. The sera tended to show parallel mean titers in II, CF and TP tests. One year after treatment there was a fall in titers of II in 66.2% of patients. The data, taken as a whole, demonstrate the usefulness of the indirect immunofluorescent test and the importance of using 2 or more serologic tests for the diagnosis and monitoring of patients with paracoccidioidomycosis. © 1985 Martinus Nijhoff/Dr W. Junk Publishers.

Pulsar test of a violation of discrete symmetries in gravitation

We determine an improved limit on C and P violation to the extended gravitational potential of Leitner and Okubo using the millisecond pulsar PSR 1937+214 data. © 1989.

Pauli nonlocality in heavy-ion rainbow scattering: A further test of the folding model

Nonlocal interactions are an intrinsically quantum phenomenon. In this work we point out that, in the context of heavy ions, such interactions can be studied through the refractive elastic scattering of these systems at intermediate energies. We show that most of the observed energy dependence of the local equivalent bare potential arises from the exchange nonlocality. The nonlocality parameter extracted from the data was found to be very close to the one obtained from folding models. The effective mass of the colliding, heavy-ion, system was found to be close to the nucleon effective mass in nuclear matter.

Genetic population data from Araraquara region (SP State, Brazil) using PowerPlex® 16 Systems

In the present study, allele frequency distributions for the 15 STR loci included in the PowerPlex® 16 Systems (Promega) were obtained from a sample of 55 unrelated individuals living in Araraquara region (SP, Brazil). The frequency of each allele for each locus tested, the exact test and the forensic and paternity parameters were calculated using POWERSTATS ver. 1.2 (Promega) and GENEPOP ver. 3.2 software. All loci are in the Hardy-Weinberg equilibrium and they reached a combined power discrimination of 0.999999999999999973 and combined power exclusion of 0.99999987, showing to be a powerful tool for paternity testing and individual identification in the population analyzed. © 2005 Elsevier B.V. All rights reserved.

Relationship between gingival clinical parameters and the reactivity of the BANA test in subgingival samples from children.

Gingivitis is the first manifestation of periodontal disease, and is characterized by painless and slow evolution. Early diagnosis and intervention must be done to avoid the possibility of precocious periodontitis during the childhood or teenage years. The enzymatic BANA test (N-benzoyl-DL-arginine-naphthylamide) was used to evaluate subgingival samples from 54 children between 6 and 9 years of age. Plaque index (PI) and gingival index (GI) were assessed according to the criteria recommended by Löe (1967). Subgingival plaque was collected from the region that featured the greatest periodontal alteration, represented by a higher gingival index. Resulting data were grouped individually according to visible and non-visible plaque and bleeding and non-bleeding gingiva. Results showed that there was no statistically significant correlation between the presence of visible plaque and the positivity of the BANA test, nor was there a statistically significant correlation between the presence of bleeding and the positivity of the BANA test in subgingival samples obtained from children. This study concluded that the BANA test is not an ideal diagnostic test to be applied to children.

Avaliação do kit TF-Test para o diagnóstico das infecções por parasitas gastrintestinais em ovinos

This study was performed to standardize parasite egg counting in feces of sheep by TF-Test, in addition to compare this test to the Gordon & Whitlock technique (G&W). Twenty-four lambs were artificially infected with Haemonchus contortus throughout 12 weeks. At the end of this time, faecal samples were taken and animals were slaughtered for worm identification and counting. G&W and TF-Test methods were carried out on each fecal sample. Both tests showed Haemonchus eggs in 95.8% of the samples (P>0.05). The correlation coefficients (r) between fecal egg counts (FEC) using G&W × Total Worm Count (TWC) were r=0.52 (not transformed data) and r=0.85 (transformed data); between FEC by TF-Test × TWC were r=0.51 (not transformed data) and r=0.87 (transformed data). Other 100 fecal samples were taken from naturally infected sheep. In these animals, the G&W and TF-Test methods showed 85% and 86% of fecal samples positive for Strongylidea eggs, respectively (P>0.05). Also in those animals, Eimeria oocysts were found in 33% of fecal samples by TF-Test, whereas in the G&W only 12% were positive (P<0.001). For Strongyloides spp., TF-Test showed 15% of positive fecal samples, whereas G&W showed 5% (P<0.05). In conclusion, both methods were efficient to diagnose gastrointestinal nematodes and TF-Test was superior to diagnose oocysts of Eimeria spp. and eggs of Strongyloides spp; conversely, Strongylidea eggs counting using TF-Test was underestimated.

Comparative studies of the sample decomposition of green and roasted coffee for determination of nutrients and data exploratory analysis

The contents of some nutrients in 35 Brazilian green and roasted coffee samples were determined by flame atomic absorption spectrometry (Ca, Mg, Fe, Cu, Mn, and Zn), flame atomic emission photometry (Na and K) and Kjeldahl (N) after preparing the samples by wet digestion procedures using i) a digester heating block and ii) a conventional microwave oven system with pressure and temperature control. The accuracy of the procedures was checked using three standard reference materials (National Institute of Standards and Technology, SRM 1573a Tomato Leaves, SRM 1547 Peach Leaves, SRM 1570a Trace Elements in Spinach). Analysis of data after application of t-test showed that results obtained by microwave-assisted digestion were more accurate than those obtained by block digester at 95% confidence level. Additionally to better accuracy, other favorable characteristics found were lower analytical blanks, lower reagent consumption, and shorter digestion time. Exploratory analysis of results using Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) showed that Na, K, Ca, Cu, Mg, and Fe were the principal elements to discriminate between green and roasted coffee samples. ©2007 Sociedade Brasileira de Química.

Rod length influence in torque measurement of SPT-T test

Since Ranzini suggested supplementing the SPT test with measurement of the torque required to turn the split spoon sampler after driving, many Brazilian engineers have been using this in the design of pile foundations. This paper presents a study of the rod length influence in the torque measurement. A theoretical study of material resistance considering torsion and bending in a thin wall tubular steel shaft was performed. It makes possible to conclude that the shearing tension caused by the proper weight represents less than 1% of the shearing tension caused by the turning moment. In addition, an experimental study was done with electric torquemeters fixed in a horizontal rod system. The tests were being carried out to analyze rods of one meter to twenty meters in length and the measurements were collected at the ends of each rod length verifying the efficiency data. As a result, it is possible to verify that the torque difference through rod length is lower than minimum scales of mechanical torquemeters that are used on practical engineering. Also a fact to be considered is a big torque loss for values under 20 N.m of applied torque. This way, the SPT-T is not adequate to low consistency soil. Copyright ASCE 2007.