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PubMed2005

Source identification of Indian opium based on chromatographic fingerprinting of amino acids.

Total and free pool of amino acids was determined in Indian opium samples using liquid chromatography (LC) with post-column opthalaldehyde derivatization followed by its fluorimetric detection. The limit of detection (LOD) was found to be in the range of 2-10 pmol with a signal to noise ratio of 3:1 and limit of quantitation (LOQ) was found to be in the range of 7-31 pmol with a signal to noise ratio of 10:1. The recovery of amino acids was found to be in the range of 86-103%. A total of 124 Indian opium samples were collected from the states of Madhya Pradesh (MP), Uttar Pradesh (UP) and Rajasthan (Raj), covering 14 licit opium growing divisions of India were chromatographically fingerprinted for the presence of various amino acids. The amino acids identified in sample hydrosylate included D, T, S, S, G, A, V, I, L, Y, F, H, K and R, while the analysis of free pool of amino acids (80% aqueous ethanol extract) indicated the presence of D, T, S, E, A, V, I, L, Y, H, K respectively. Multiple discriminant analysis was applied to the quantitative total amino acid data to determine an optimal classifier in order to evaluate the source of Indian opium. The foremost amino acid variables that accounted for the true discrimination were identified as D, E, G, A, F and K in evaluating the geographical origin of Indian opium and the predictive value based on the discriminant analysis was found to be 90% in relation to the source of opium samples. Chemometrics performed with amino acid analytical data was used successfully in discriminating the licit opium growing divisions of India into three major groups, viz. groups I, II and III. The methodology developed may find wide application in forensic analysis.

Amino Acids↗
PubMed1995

Assessment of data sets containing a considerable number of values below the detection limits.

Using real examples it is demonstrated that the concentrations of non-essential substances in biological systems always follow a statistical log-normal distribution. This is based on the assumption that in a first-order approximation the rate of excretion of the quantity of unwanted molecules or atoms in the biological system is only dependent on their concentration. Applying a natural logarithmic transformation, the resulting log-normal distribution always has a standard deviation of about 1, as shown by statistical analysis of more than 680 clusters of analytical results. Assuming a log-normal distribution with a standard deviation of 1, it is possible to derive factors for the estimation of percentiles, such as the median, even when this percentile is below the detection limit; quantifiable and higher percentiles only must be multiplied by a specific factor. This new method has the advantage that no arbitrary assumptions must be made about artificial parameters such as the numerical treatment of non-detectable analytical data. The assumptions used for the calculation of the factors are justified by proof with experimental data. The applicability of the new method is demonstrated for various contaminants in various plants and animals.

Animals↗
PubMed2005

Bone mineral density in familial amyloid polyneuropathy and in other neuromuscular disorders.

Neuromuscular diseases are a known risk factor for immobilization-induced osteoporosis. The aim of the study was to analyse bone mineral density (BMD) in patients with familial amyloid polyneuropathy (FAP) type I (Val30 Met) and to compare them with a population of patients with other neuromuscular disorders. We studied 24, ambulatory, neuromuscular patients, all men and premenopausal women. We included 12 FAP patients (GI) and 12 patients with other disorders (GII). Clinical data included age, sex, height, weight, alcohol intake, smoking, calcium intake, physical activity and history of fractures. Serum and urinary calcium, osteocalcin, bone alkaline phosphatase, parathyroid hormone, thyroid stimulating hormone and urinary N-telopeptide cross-linked type 1 collagen were determined in all patients. Bone mineral density of lumbar spine, hip and wrist were determined by dual energy X-ray absorptiometry scan. No statistical differences were found in clinical or analytic data between the two groups, except for body mass index and calciuria, which were lower in GI. In GI, 54.5% were osteoporotic, against 23.1% in GII (P = 0.04). Bone mineral density was lower in GI when compared with GII, and tended to decrease with disease duration. Decreased BMI and the early autonomic involvement in GI probably explain the results. The prevention and early treatment of osteoporosis, in FAP patients should be considered a priority.

Absorptiometry, Photon↗
PubMedDate not supplied

Analytical quality assurance for the WHO GEMS/Food-EURO programme--results of 1993/94 laboratory proficiency testing.

As a means of assessing the performance of European laboratories who contribute analytical data on food contamination to the World Health Organization (WHO) Global Environmental Monitoring Scheme (GEMS), a series of five proficiency testing exercises were carried out during 1993 and 1994. In total 136 laboratories from 21 different countries took part in one or more of the exercises which covered the analysis of trace elements (lead, cadmium and mercury) in milk powder, pesticides (organochlorine, organophosphorus and pyrethroid) in spinach powder, nitrate in spinach powder, aflatoxins in nut-based animal feed and patulin in apple juices. The proficiency testing was carried out according to the ISO/IUPAC/AOAC INTERNATIONAL Harmonized Protocol and laboratories were awarded z-scores signifying their analytical capability based on their reported results for each of the respective exercises. Overall 60% of laboratories were satisfactory for accuracy for trace element analysis, 41% for pesticides, 43% for nitrate, 88% for aflatoxins and 53% for patulin. These results gave an overall poorer performance (68%) than the average for other similar schemes (79%), indicating the need for care in collating data for such programmes as GEMS and the need for remedial measures to assist in improving performance.

Aflatoxin B1↗
PubMed1994

Long-term compliance of intensified insulin therapy.

Results of the DCCT trial (N. Engl. J. Med. 329, 977-986) demonstrate that therapy in insulin-dependent diabetes mellitus (IDDM) should aim at near-normoglycemia. For reaching this standard, intensified insulin therapy--either intensified conventional therapy (ICT) or continuous subcutaneous insulin infusion (CSII)--is mandatory. These regimes demand much long-term motivation and discipline from the diabetics. With > 95%, long-term compliance of ICT is good, according to the few published data available and our own experience. For CSII, on the other hand, cumulated studies reveal discontinuation rates ranging from 0% to 36%, averaging 20.4% and being significantly correlated with metabolic control before start of CSII in terms of glycosylated hemoglobin levels (r = 0.66; P < 0.05). The major reasons for discontinuation of CSII were skin problems (22.1%), inconvenience of the pump (21.4%) and lack of metabolic improvement (9.6%). A conclusion drawn from these meta-analytical data is that a stepwise approach to CSII is recommended for increasing compliance. A period of ICT long enough to gain experience with blood glucose self-control and self-adjustment of meal-related insulin should precede CSII. Furthermore, a general increase of CSII among IDDM patients is necessary to come closer to the standard of near-normoglycemia for these diabetics. Therefore, diabetes treatment and education resources must be improved, especially concerning psychosocial problem solving and cooperation between diabetologists and general practitioners.

Biomarkers↗
PubMedDate not supplied

The radiochemist's role in the quality evaluation and assessment of radiological data in environmental decision making.

The quality evaluation and assessment of radiological data is the final step in the overall environmental data decisionprocess. This quality evaluation and assessment process is performed outside of the laboratory, and generally the radiochemist is not involved. However, with the laboratory quality management systems in place today, the data packages of radiochemical analyses are frequently much more complex than the project/program manager can effectively handle and additionally, with little involvement from radiochemists in this process, the potential for misinterpretation of radiological data is increasing. The quality evaluation and assessment of radiochemistry data consists of making three decisions for each sample and result, remembering that the laboratory reports all the data for each analyses as well as the uncertainty in each of these analyses. Therefore, at the data evaluation and assessment stage, the decisions are: (1) is the radionuclide of concern detected (each data point always has a number associated with it?); (2) is the uncertainty associated with the result greater than would normally be expected; and (3) if the laboratory rejected the analyses is there serious consequences to other samples in the same group? The need for the radiochemist's expertise for this process is clear. Quality evaluation and assessment requires the input of the radiochemist particularly in radiochemistry because of the lack of redundancy in the analytical data. This paper describes the role of the radiochemist in the quality assessment of radiochemical data for environmental decision making.

Data Collection↗
PubMed2001

Recent interview-based measures of competency to stand trial: a critical review augmented with research data.

Forensic experts are frequently asked to conduct competency-to-stand trial evaluations and address the substantive prongs propounded in Dusky v. United States (1960). In understanding its application to competency evaluations, alternative conceptualizations of Dusky are critically examined. With Dusky providing the conceptual framework, three interview-based competency measures are reviewed: the Georgia Court Competency Test (GCCT), the MacArthur Competence Assessment Tool-Criminal Adjudication (Mac-CAT-CA), and the Evaluation of Competency to Stand Trial-Revised (ECST-R). This review has a twin focus on reliability of each measure and its correspondence to Dusky prongs. The current review is augmented by new factor analytic data on the MacCAT-CA and ECST-R. The article concludes with specific recommendations for competency evaluations.

Criminal Psychology↗
PubMed2006

Preparative laser capture microdissection and single-pot cell wall material preparation: a novel method for tissue-specific analysis.

In adaptation to their function the walls of plant cell display tissue-specific variations of composition according to their developmental stage, cell type and stress of various origin. It is therefore important to obtain a precise analytical data describing the cell wall composition with respect to these different factors. In the present work, laser capture microdissection (LCM) was used for isolating different tissues from the stem of Urtica dioica L. at a semi-preparative scale. The technique was associated for the first time to a one-pot sequential cell wall preparation and hydrolysis for the carbohydrate analysis of each cell type. The results demonstrate that the combination of LCM and micro-analytical methods can provide individual cell type composition and should improve our knowledge of the biochemical diversity of cell walls in plants. This approach will be of potential interest for the understanding of the effects of stress or genetic engineering on the composition of the cell walls.

Carbohydrates↗
PubMed2005

Preliminary data on polybrominated diphenyl ethers (PBDEs) in farmed fish tissues (Salmo salar) and fish feed in Southern Chile.

Polybrominated diphenyl ethers (PBDEs) have become an issue of global concern. Recent studies have shown that farmed salmon can accumulate high levels of brominated compounds in their tissues and consequently there is a growing concern on its industrial and public health impacts. Little information is found in the international literature on PBDEs in the biotic compartment of the Southern Hemisphere. This paper reports the levels of several PBDE congeners found in the tissues of farmed fish from five different farming areas of Southern Chile. PBDEs were analyzed by HRGC-MS. More analytical data were obtained by analyzing these same pollutants in fish feed. Our results indicate a general trend of PBDE levels averaging 1.46 ng g(-1) wet weight (wwt). The observed congeneric distribution that resulted was quite similar to data previously reported in the open literature. PBDE profiles were found to be dominated by BDE 47. No correlation was observed between levels found in the tissues and the lipid content in such tissues, although a high correlation with the fish feed data was observed indicating that this could probably be the main PDBE entry source into fish, although other sources cannot be excluded. Even though the samples were obtained from different geographical areas, they presented fairly similar profiles, indicating a potential common source. We concluded that PBDE levels in the farmed Chilean salmon are in the low average range of values published in the open literature.

Animals↗
PubMed1976

Biogenesis of matrix vesicles in cartilage growth plates.

Although the structure and function of cartilage matrix vesicles have been comprehensively documented in the literature, the method of vesicle production and export to the extra-cellular matrix is less well understood. The existing data are grouped into four general hypotheses of matrix vesicle biogenesis, with a consideration of the relative merits and weaknesses of each postulate. The hypotheses are: a) budding from cellular processes; b) extrusion of preformed structures; c) cellular degeneration and disintegration; and c)subunit secretion and extracellular assembly. Each of these possibilities offers conceptual advantages and disadvantages, so that it is difficult to adopt a monistic stance. Previous notions of vesicle biogenesis have derived from statis morphologic and analytical data, which are necessarily limiting when attempting to draw kinetic conclusions. Radiotracer studies of lipid synthesis and transport in cartilage lead to the conclusion that matrix vesicles in the growth plate are derived from chondrocytes; the present data favor the hypotheses of budding from cellular processes and/or subunit secretion with extracellular self-assembly.

Cartilage↗
PubMed1992

The evolution of toxic effluents in fires and the assessment of toxic hazard.

Toxic hazard in fire depends upon three factors: the fire growth curve (mass loss rate of materials, kg/min) and volume dispersal (kg/m3), the yields of toxic products (e.g. kg CO/kg fuel burned) and the toxic potency of the products (exposure dose needed to cause toxic effects, e.g. lethal dose of CO in ppm.min). The first and second sets of data are obtainable from large-scale tests or small-scale tests and mathematical modelling, the third and some information on the second are derived from toxicity studies of combustion products in small-scale tests or of individual fire gases. Small-scale toxicity test data on materials expressed as lethal mass loss exposure doses (LCt50 g min m-3) can be used in Fractional Effective Dose (FED) hazard assessments, providing the decomposition conditions of the test reproduce those in the fire being examined; principally either non-flaming oxidative, early well-ventilated flaming, or vitiated post-flashover. Although bioassays are needed for a full toxicity assessment, it is now possible to predict the toxic potency of materials to some extent from analytical data alone. The suitability of the small-scale test decomposition conditions are determined in terms of non-flaming or flaming behaviour, temperature (or radiant flux), CO2/CO ratio and oxygen concentration. Existing small-scale test methods provide reasonable models for materials under non-flaming oxidative and early flaming conditions, although the data base for the latter is poor. Only the DIN 53436 method is able to model vitiated post-flashover decomposition conditions, but data for this condition are almost non-existent.

Animals↗
PubMedDate not supplied

Epidemiology of digestive tract cancers in India IV. Gall bladder and pancreas.

Pancreatic cancer is a leading cause of cancer-related deaths in developed countries. Gall bladder cancer is very common in South American countries, around the Mediterranean and in Japan. A majority of patients with these cancers receive only palliative therapy in spite of recent advances in investigation and surgery. Their poor prognosis and increasing incidence in India necessitate a better epidemiologic approach towards their control. This review is based on epidemiological data, publications and abstracts from India. Population-based data reveal that the incidence of gall bladder cancer is very high in northern Indian cities (5-7 per 100,000 women) and low (0-0.7 per 100,000 women) in southern India. The distribution suggests a high-incidence region comprising Uttar Pradesh, Bihar, Orissa, West Bengal and Assam. The cancer is twice more common in women and is the leading cancer among digestive cancers in women in the northern Indian cities of Delhi and Bhopal. There are few analytical data to hypothesize why this geographical predisposition. The high incidence is also observed in north Indian immigrants to the United Kingdom. The incidence of pancreatic cancer is low (0.5-2.4 per 100,000 men and 0.2-1.8 per 100,000 women) in most parts of India. Somewhat higher rates are seen in the male urban populations of western and northern India. Studies from Kerala support an association between tropical pancreatitis and pancreatic cancer. Time trends reveal an increase in the incidence of gall bladder and pancreas cancers; the increase in the former is alarming. We estimate that the approximate annual cancer burden of India in 2001 would include 17,730 cases of gallbladder cancer and 14,230 of pancreatic cancer. Multi-center studies are needed to identify potentially preventable risk factors associated with gall bladder and pancreatic cancer in India.

Age Factors↗
PubMed1998

Influence of long-term fertilization on the selenium content of calcareous chernozem soil.

Available data on the selenium (Se) content in Yugoslavian soils indicate that the element is present in small amounts (< 500 microg/kg in Se-deficient soils). There are no data on the effect of various fertilizers on the Se content in Yugoslavian soils. In our study, we examined the effect of the long-term application of mineral and organic fertilizers (farmyard manure and cornstalks) on the content of Se in calcareous chernozem soil. The experiment of the Maize Research Institute in Belgrade was set up in 1971 and soil samples were examined by chemical analysis after 23 years. The following important conclusions can be drawn based on the analytical data obtained. The total content of Se in the investigated experimental variants in calcareous chernozem soil ranges from 166 to 593 microg/kg. All the variants had a higher content of Se than soil samples taken before the experiment was set up. Comparison with the control (variant without fertilizers) indicated that the Se content increased in the experimental variants where farmyard manure had been applied. This effect was noticed to a depth of 80 cm. Application of farmyard manure should be considered as a means of increasing the levels of Se in Se-deficient soil. Correlation coefficients between total Se content in the soil and some important agrochemical properties of the investigated soils are presented in this paper.

Agriculture↗
PubMedDate not supplied

A kinetic model of benzoylecgonine disposition after cocaine administration in humans.

Cocaine (C) and benzoylecgonine (BZ) plasma levels and urinary excretion rate data from a series of intravenous cocaine studies were used to develop a kinetic model for C and BZ, with the main objective of characterizing BZ disposition. Kinetic analyses were made with the CONSAM 30 computer program. Under assumptions of the model, calculated parameters indicated a BZ distribution volume of 50 L, a half-time for BZ formation of 1.9 h and a BZ excretion half-time of 4.7 h. The model may eventually provide a basis for interpretation of analytical data on isolated samples of plasma or urine.

Adult↗
PubMed1997

Basic concepts of artificial neural networks (ANN) modeling in the application to pharmaceutical development.

Artificial neural networks (ANN) methodology is a new modeling method that has not been broadly applied to pharmaceutical sciences up to now. The aim of this paper is to give a detailed description of the associating networks as well as a description of less well-known networks (i.e., feature-extracting and nonadaptive networks) and their scope of application in pharmaceutical sciences. The descriptions include the historical origin and the basic concepts behind the computing. ANN are based on the attempt to model the neural networks of the brain. Learning algorithms for associating ANN use mathematical procedures usually derived from the gradient descent method whereas feature-extracting ANN map multidimensional input data sets onto two-dimensional spaces. Nonadaptive ANN map data sets and are able to reconstruct their patterns when presented with corrupted or noisy samples. Associating networks can typically be applied in the pharmaceutical field as an alternative to traditional response surface methodology, feature-extracting networks as alternative to principal component analysis, and nonadaptive networks for image recognition. Based on these abilities, the potential application fields of the ANN methodology in the pharmaceutical sciences is broad, ranging from clinical pharmacy through biopharmacy, drug and dosage form design, to interpretation of analytical data. The few applications presented in the pharmaceutical technology area seem promising and should be investigated in more detail.

Algorithms↗
PubMed2002

Crystal structure and thermal behavior of nedocromil nickel octahydrate.

The hydration behavior of a salt depends on the nature of the cation and the anion and on the molecular packing. A transition metal salt (nickel) of nedocromil was prepared and its crystal structure was elucidated in an attempt to study the influence of the nature of the bivalent cation on the structure, water interactions and molecular packing. Crystal data: nedocromil nickel octahydrate (NNi), orthorhombic, Pca2(1), a=29.5446(1) A, b=25.0444(1) A, c=13.3767(2) A, Z=16. The Ni2+, has octahedral coordination, but the coordination environments of the cations and the bonding environments of the water molecules differ. NNi contains four Ni2+ ions in the asymmetric unit, two of which are each octahedrally coordinated to five water molecules and to a carboxyl oxygen. The two remaining Ni2+ ions are linked in a Ni2(H2O)10(+4) species. Thermal analytical data for NNi show that the water molecules in this hydrate are lost in a single step dehydration, which may be attributed to the fairly continuous water layer in the ac plane of the crystal lattice.

Anti-Inflammatory Agents↗
PubMed2001

Limitations to the use of solid-phase microextraction for quantitation of mixtures of volatile organic sulfur compounds.

A study of the range of volatile organic sulfur compounds produced by brassica plants has highlighted limitations to the use of Carboxen/PDMS fibers for their analysis by solid-phase microextraction (SPME). These fibers are sometimes advocated for the analysis of sulfur gases, but a quantitative comparison of analytical data derived by SPME and by direct gas sampling of standard mixtures of volatile low molecular weight sulfur compounds at 0.01-10 mg/L has identified potential errors associated with their use. Higher molecular compounds displace lower molecular weight compounds as a consequence of competition for active sites on the fiber, and the relative proportions of the components adsorbed onto the fiber depend on their ratio in the headspace. As their relative concentrations change from sample to sample, the varying interactions result in irregular analytical responses, reflected in erratic calibration curves. Standards containing single components are not valid; only a standard containing all components found in the sample to be analyzed, and at the same relative concentrations, is appropriate. In practice, this may preclude the use of the fibers for quantitative analysis of multicomponent mixtures.

Journal Article↗
PubMedDate not supplied

[The prediction of postoperative septic complications by means of nutritional parameters. II. The verification of the predictive formula].

An assessment was made of the predictive capacity of the following predictive formulation named Nutritional Sepsis Risk: NSR = 14.26 - 1.76 (albumin) - 1.47 (risk area) This was done in a sample of 65 surgery patients with digestive pathology who were candidates for selective surgery. All had undergone a pre-operative nutritional evaluation program, based on anthropometric and analytical data and Retarded Hypersensitivity Cutaneous Tests (RHCT). NSR was calculated pre-operatively. Infections were assessed qualitatively and quantitatively using Elebeute and Stoner's sepsis index. There were a total of five post-operative infections (7.69%). The NSR intersection point was calculated with an ROC curve, situated in a score of 3. The NSR detected the five infections, so is 100% sensitive, with 70% specificity and, in the detection of the septic risk population, surpassed the other nutritional parameters, whether anthropometric or analytical, and the RHCTs, when they were studied individually.

Aged↗