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Viability Reagent, PrestoBlue, in Comparison with Other Available Reagents, Utilized in Cytotoxicity and Antimicrobial Assays  [PDF]
Namrita Lall,Cynthia Joan Henley-Smith,Marco Nuno De Canha,Carel Basson Oosthuizen,Danielle Berrington
International Journal of Microbiology , 2013, DOI: 10.1155/2013/420601
Abstract: This study compared different commercially available viability reagents. The growth indicator reagents include p-iodonitrotetrazolium violet (INT), PrestoBlue, and Alamar Blue which were used for antimicrobial analysis against Streptococcus mutans, Prevotella intermedia, Propionibacterium acnes, and Mycobacterium tuberculosis. PrestoBlue and Alamar Blue are resazurin based reagents that resulted in a quick and easily distinguishable colour change that allowed for visual readings. INT and Sodium 3′-[1-(phenyl amino-carbonyl)-3,4-tetrazolium]-bis-[4-methoxy-6-nitro] benzene sulfonic acid hydrate (XTT) are tetrazolium based reagents which are converted to a formazan dye in the presence of metabolically active mitochondria enzyme. For cell viability analysis, reagents XTT and PrestoBlue were compared. PrestoBlue was able to clearly indicate the minimum inhibitory concentration (MIC) of various positive drug controls on various microbial strains. PrestoBlue was also a good indicator of the 50% inhibitory concentration (IC50) of positive drug controls on various cell lines. 1. Introduction PrestoBlue and Alamar Blue reagents are resazurin based, membrane permeable solutions that upon reduction form resorufin, a red fluorescent compound which can be quantitatively measured to determine viability. Initially developed as a cell viability indicator, PrestoBlue has been indicated for use on nonmammalian cells, such as bacteria, yeast, and eukaryotic cells. The variable reading methods of PrestoBlue makes this reagent an attractive alternative in cellular and microbiology. PrestoBlue can be measured either visually, using absorbance or utilising the fluorescent outputs of the reduced resorufin [1]. p-iodonitrotetrazolium violet (INT) is a tetrazolium dye precursor that once reduced forms a purple formazan dye (Sigma-Aldrich). Sodium 3′-[1-(phenyl amino-carbonyl)-3,4-tetrazolium]-bis-[4-methoxy-6-nitro] benzene sulfonic acid hydrate (XTT) is also a tetrazolium based reagents which in the presence of metabolically active cells reduces the tetrazolium salt to an orange coloured formazan compound. The reduction of the tetrazolium salt is due to the activity of the mitochondria enzyme in the active cells. The intensity of the formazan compound can be measured using absorbance where the intensity of the compound is directly proportional to the number of metabolically active cells [2]. The aim of this study was to validate the use of PrestoBlue as a growth indicator and cell viability reagent by comparing it to other similar commercially available reagents. 2. Materials
Sodium Valproate and Sodium Dimercaptopropane Sulfonate, No Binding To Tetramine and No Reduction of Blood Tetramine Level  [cached]
Viroj WIWANITKIT
Journal of Neurological Sciences , 2012,
Abstract: Tetramine is considered as a highly poisonous substance that can cause the neurological disorder to anyone who intake it within a few minutes. The clonic tonic seizure can be developed and death can be the finalized result. Here, the author assesses whether the two presently used antidotes have any possibility to reduce the tetramine level in blood level. The author tries to us e a molecular docking technique to study the mechanism of sodium valproate and sodium dimercaptopropane on tetramine. Of interest, there is no detected interaction. This confirms the fact that there is no direct neutralization effect. Hence, it can explain the fact that there is no significant reduction of blood tetramine level in intoxication case after getting the two antidotes.
Rapid spectrophotometric determination of trace amounts of chromium using variamine blue as a chromogenic reagent
Narayana, B.;Cherian, Tom;
Journal of the Brazilian Chemical Society , 2005, DOI: 10.1590/S0103-50532005000200011
Abstract: a simple, rapid and sensitive spectrophotometric method has been developed for the determination of trace amounts of chromium using variamine blue as a chromogenic reagent. the proposed method is based on the reaction of chromium(vi) with potassium iodide in acid medium to liberate iodine, which oxidizes variamine blue to form a violet colored species having an absorption maximum 556 nm. beer's law is obeyed in the range 2-12 mg ml-1 of cr(vi). the molar absorptivity, sandell's sensitivity, detection limit and quantitation limit of the method were found to be 0.911×104 l mol-1 cm-1, 1.14×10-2 mg cm-2, 0.02 mg ml-1 and 0.07 mg ml-1 respectively. the optimum reaction conditions and other analytical conditions were evaluated. the effect of interfering ions on the determination is described. the chromium(iii) can be determined after it is oxidized with bromine water in alkaline medium to chromium(vi). the developed method has been successfully applied to the analysis of the chromium in alloy steels, industrial effluents, natural water samples and soil samples.
Simple Analysis Used in Diagnosis and Follow-up of Schizophrenic Patients  [PDF]
Faten A. Nour El-Dien,Reham G. El-Nahas,Ahmed G. El-Nahas
Journal of Analytical Methods in Chemistry , 2006, DOI: 10.1155/jammc/2006/79038
Abstract: Dopamine acts as neurotransmitter in the central and peripheral sympathetic nervous system. Determination of dopamine (DO) was performed by spectrophotometric analysis depending on the formation of new colored compound. The proposed procedure was efficient in quantitative determination of DO as pure material in pharmaceutical preparations and in urine samples. DO concentration in urine sample of patient confirms the affection with schizophrenia and the proposed procedure was used to facilitate diagnosis and followup of schizophrenic patients. It is recommended to apply the proposed procedures as routine analysis in pharmaceutical companies for quality control and in analytical laboratories to diagnose and follow up schizophrenia.
SPECTROPHOTOMETRIC DETERMINATION OF CEPHALEXIN USING NINHYDRIN REAGENT IN TABLET DOSAGE FORM  [PDF]
Patel Satish A,Patel Natavarlal J.
International Research Journal of Pharmacy , 2011,
Abstract: A simple, sensitive, accurate, precise and economical visible spectrophotometric method was developed and validated for the estimation of cephalexin in tablets. The method is based on the reaction of cephalexin with ninhydrin reagent in methanol giving blue color chromogen, which shows maximum absorbance at 576 nm against reagent blank. The chromogen obeyed Beer’s law in the concentration range of 5-60 μg/ml for cephalexin. The results of the analysis have been validated statistically and by recovery studies.
COGNITIVE COMPLEXITY OF SCHIZOPHRENIC PATIENTS  [PDF]
Sne?ana Manojlovi?,Julijana Nikoli?-Popovi?
Acta Medica Medianae , 2002,
Abstract: The aim of the paper is to determine precisely the conceptual organization characteristics expressed in cognitive complexity. This would provide for an application of specific therapeutic techniques for the sake of compensating for the primary cognitive deficit.The paper presents an examination of cognitive complexity in schizophrenic patients in comparison with a group of normal subjects by applying the test of role playing. The test is carried out in the phase of the presence of psychotic symptoms and after its withdrawal.The results show that there is neither in the first nor in the second measurement any significant difference in the cognitive complexity score between the schizophrenic and the normal subjects.The cognitive complexity reflects the formal potential of the conceptual organization to differentiate meanings. The schizophrenic patients' inability to achieve the real meaning along with the potential for the formally.differentiated conceptual organization point to the weakness of the conceptual organization that is manifested in inconsistency.
Quality of Life in Schizophrenic Patients  [cached]
Naema Khodadadi,Mojgan Baghaie,Haeideh Mahmudi,Farzaneh Sheikholeslami
Zahedan Journal of Research in Medical Sciences , 2012,
Abstract: Background: Nowadays, quality of life (QoL) is an important indicator of treatment outcome and it's evaluation in schizophrenic patients will be vital. So, this study is conducted to compare QoL in schizophrenic patients and healthy people in Rasht, Guilan.Materials and Method: This study is a cross-sectional descriptive survey that was done on 52 patients with schizophrenia referred to Shafa hospital with convenience sampling method and 153 healthy people of Rasht by cluster method. Data collection instrument was a 3 part questionnaire consisting demographic-social questionnaire, WHO QoL questionnaire, and mental status assessment form. Data gathered by interview and analyzed with SPSS software using descriptive and inferential statistics (χ2, ANOVA, independent-t test). Results: Our finding indicated that patients and healthy individuals QoL had overall statistically significant difference (p<0.0001), and it's general (p<0.006), physical (p<0.0001), psychiatric (p<0.001), and social relationship (p<0.015). Conclusion: According result, schizophrenic clients compare with healthy people had lower QoL level that need special attention to improve treatment and their post-discharge care with focus on social relationship in this group of patients.
Nightmare in schizophrenic and depressed patients
Okorome Mume,Celestine;
The European Journal of Psychiatry , 2009, DOI: 10.4321/S0213-61632009000300006
Abstract: background and objectives: nightmare is a common sleep disorder. while a sleep disorder such as insomnia can readily be associated with psychiatric disorders, the same cannot be said of nightmare. the objective of this study was to determine the prevalence rate of nightmare in a sample of psychiatric patients, and to compare this rate with the rate obtained in age- and sex- matched healthy control subjects in order to determine if there is a significant difference in the rates of nightmare in the different groups. methods: ninety - four randomly selected psychiatric patients made up of 54 schizophrenic patients and 40 depressed patients were recruited into the study. one hundred and twenty - three age- and sex- matched randomly selected control subjects were also recruited into the study. a questionnaire determining the one year prevalence of nightmare was administered to all the subjects. each of them was required to indicate whether he or she had experienced nightmare in the previous one year and if so to indicate the number of episodes experienced during the said period. results: the results showed prevalent rates of nightmare of 4.9%, 16.7% and 17.5% respectively for the healthy control subjects, schizophrenic patients and depressed patients. there was an overall prevalence rate of 17% among the psychiatric patients (schizophrenic patients and depressed patients) as against 4.9% in the healthy control subjects. among those who experienced nightmare, the mean values for the number of episodes within the previous one year were, respectively 18 (sd = 6.6) for healthy control subjects (n = 6), 42.7 (sd = 6.3) for schizophrenic patients (n = 9) and 44.6 (sd = 5.9) for depressed patients (n = 7). conclusions: the findings in this study provide support for a significant association between nightmare and schizophrenia as well as nightmare and depressive illness. in effect, there is a significant association between nightmare and psychopathology.
Nightmare in schizophrenic and depressed patients  [cached]
Celestine Okorome Mume
The European Journal of Psychiatry , 2009,
Abstract: Background and Objectives: Nightmare is a common sleep disorder. While a sleep disorder such as insomnia can readily be associated with psychiatric disorders, the same cannot be said of nightmare. The objective of this study was to determine the prevalence rate of nightmare in a sample of psychiatric patients, and to compare this rate with the rate obtained in age- and sex- matched healthy control subjects in order to determine if there is a significant difference in the rates of nightmare in the different groups. Methods: Ninety - four randomly selected psychiatric patients made up of 54 schizophrenic patients and 40 depressed patients were recruited into the study. One hundred and twenty - three age- and sex- matched randomly selected control subjects were also recruited into the study. A questionnaire determining the one year prevalence of nightmare was administered to all the subjects. Each of them was required to indicate whether he or she had experienced nightmare in the previous one year and if so to indicate the number of episodes experienced during the said period. Results: The results showed prevalent rates of nightmare of 4.9%, 16.7% and 17.5% respectively for the healthy control subjects, schizophrenic patients and depressed patients. There was an overall prevalence rate of 17% among the psychiatric patients (schizophrenic patients and depressed patients) as against 4.9% in the healthy control subjects. Among those who experienced nightmare, the mean values for the number of episodes within the previous one year were, respectively 18 (sd = 6.6) for healthy control subjects (n = 6), 42.7 (sd = 6.3) for schizophrenic patients (n = 9) and 44.6 (sd = 5.9) for depressed patients (n = 7). Conclusions: The findings in this study provide support for a significant association between nightmare and schizophrenia as well as nightmare and depressive illness. In effect, there is a significant association between nightmare and psychopathology.
Schizophrenic Representative Investors  [PDF]
Philip Z. Maymin
Quantitative Finance , 2010,
Abstract: Representative investors whose behaviour is modelled by a deterministic finite automaton generate complexity both in the time series of each asset and in the cross-sectional correlation when the rule governing their behaviour is schizophrenic, meaning the investor must hold multiple seemingly contradictory beliefs simultaneously, either by switching between two different rules at each time step, or computing different responses to different assets.
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