Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0040822 (tremor)
 18,428 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Functional observational battery suggested by EPA, was applied to neurotoxicity screening studies. In previous experiments an organophosphorous pesticide, chlorfenvinphos (CVP), was used. It was administered intraperitoneally to male rats at the doses of 1, 3, 6 mg/kg of body weight; edible oil was administered to the control group. Tests were performed 3 hrs, 24 hrs and 7 days after the administration of the these substances. The set of tests concerned motor, sensory and vegetative functions. The influence of the dose of 6 mg/kg on rats was particularly evident. A number of disorders, like tremor, hypersalivation, dysbasia and hypotaxia, not observed in animals to which lower doses of CVP had been administered, were noticed. The mortality rate in this group was 25%. Earlier studies revealed neurotoxicity of CVP administered at the dose of 3 mg/kg, which when compared to the present results of the experiment indicates low sensitivity of this battery of tests taken as a whole. The disadvantage of the battery lies also in applying the quality evaluation scale in many cases, which makes carrying out statistical analysis difficult. Behaviours not formulated in this scale were observed. The observation of animal locomotor activity proved to be the most reliable and objective neurotoxicity evaluation index both in the previous and present studies.
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PMID:[Evaluation of the functional observational battery of tests used for neurotoxicity detection based on the effects of exposure to chlorfenvinphos]. 837 39

We report a 85-year-old woman who had an onset of gait disturbance at 80 years of the age. She had a dizzy spell when she was 80-year-old. She was evaluated at another hospital where paroxysmal tachycardia and sinus arrest lasting as long as 5.8 seconds were found. She was diagnosed as having sick sinus syndrome and a pace maker was inserted. She had a gradual onset of disturbance of gait shortly after the above dizzy spell. She became unable to walk fast and her steps became small. Neurologic examination at age 83 revealed small step gait with freezing episodes. Retropulsion was present. No motor weakness or origidity was noted. She had no tremor. Mentally she was alert and sound. Cranial nerves were essentially normal. Cranial CT scan revealed slight diffuse low density change in the bilateral cerebral white matter. She was treated with amantadine HCI and levodopa with carbidopa. Her gait and balance showed some improvement. She developed pneumonia and worsening of her gait when she was 85 years of the age, and she was admitted again to our hospital. She was mentally alert and sound but she showed marked freezing of gait with loss of postural reflex; she would have fallen down unless supported upon standing. Cranial nerves were again essentially normal. Her hospital course was complicated by pneumonia, DIC, and renal failure. She expired suddenly on the 10th day of her last admission. She was discussed in a neurological CPC and the chief discussant arrived at the conclusion that the patient had vascular parkinsonism due to lacunar state. However, paucity of vascular changes in her CT scan remained as a question. Other participants thought that she had nigral cell loss secondary to her aging and circulatory disturbance which would have been caused by her sick sinus syndrome. Post-mortem examination revealed marked loss of nigral pigmented cells; the cell loss was diffusely seen in the substantia nigra. Neurofibrillary tangles were seen in the remaining neurons. In addition, gliosis was noted in the globus pallidus and the subthalamic nucleus, however, neuronal loss was very mild in those nuclei. In the superior colliculus, neuronal loss was mild, however, gliosis was seen. No clear neuronal loss was observed in the locus coeruleus, however, Lewy bodies were seen in the remaining neurons. Furthermore, Lewy bodies were also found in the substantia sigra. It was thought that she had progressive supranuclear play (PSP). Question was whether or not she was complicated by Parkinson's disease. Clinically, she had no rigidity or tremor. Pathologically, locus coeruleus did not show neuronal loss. Therefore, incidental Lewy body disease was raised as a possibility. Finally, it should be pointed out that she had no oculomotor disturbance or dementia, yet she had PSP. Her clinical features were those of pure akinesia. Pathologic changes were also relatively mild except for those in the substantia nigra. Possibility of post-encephalitic parkinsonism without encephalitis was also discussed, however, over all distribution of her pathologic changes was more consistent with PSP.
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PMID:[A 85-year-old woman with the onset of progressive gait disturbance at 80 years of the age]. 912 48

The effect of germination on the protein content and in the level of specific activity of lipoxygenase-1 on seedlings of Santa Rosa, FT-2 and Davis soybean cultivars were studied. Soybean seeds of the three cultivars were germinated from 0 to 72 hours in a seed germinator at 30 degrees C temperature, 100% relative humidity, and absence of light. The seeds were then frozen in liquid nitrogen, freeze-dried and milled. The lipoxygenase-1 was extracted with 0.02M thris-HCI buffer at pH = 8.2 and 13% saccharose for 30 minutes at 4 degrees C without shaking. The highest levels of specific activity of lipoxygenase-1 per milligram of flour (dry basis) in the Santa Rosa, FT-2 and Davis cultivars were observed between 18 and 36, 18 and 24, and 0 and 12 hours, respectively. The polinomial quadratic model best fits the regression analysis of the variable levels of specific lipoxygenase activity for cultivar Davis (R2 = 0.9197). Although for cultivars Santa Rosa (R2 = 0.9041)., and FT-2 (R2 = 0.7486) the 4th degree polynomial model has shown the best fit. The protein content in the three cultivars studied reached the maximum values at 48h germination. The germination induced a relative increase of the protein content but caused a reduction of the level of specific lipoxygenase-1 activity.
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PMID:Effect of germination on the protein content and on the level of specific activity of lipoxygenase-1 in seedlings of three soybean cultivars. 933 5

A method is reported for the determination of cyromazine and melamine residues in soil. Soil samples are extracted twice via mechanical shaking, each time with 70% acetonitrile/30% 0.050 M ammomium carbonate for 30 min. An aliquot portion of the pooled extracts is subjected to strong cation exchange (SCX) purification on AG 50W-X4 resin. Final analysis is accomplished using liquid chromatography-ultraviolet (LC-UV) detection at a wavelength of 214 nm. Confirmatory analyses can be performed using gas chromatography-mass selective detection (GC-MSD) in the selected ion monitoring (SIM) mode. The limit of detection (LOD) is 2.5 ng injected and the limit of quantification (LOQ) is 10 ppb when using LC-UV for the analysis of N-cyclopropyl-1,3,5-triazine-2,4, 6-triamine (cyromazine) and 1,3,5-triazine-2,4,6-triamine (melamine). The LOD is 0.050 ng injected and the LOQ is 10 ppb when using GC-MSD for confirmatory analyses. The mean procedural recoveries were 97 and 95% and the standard deviations were 16 and 11% for cyromazine and melamine, respectively (n = 24), when using LC-UV. The mean procedural recoveries were 107 and 92% and the standard deviations were 9.9 and 16% for cyromazine and melamine, respectively (n = 29), when using GC-MSD. The method validation study was conducted under U.S. EPA FIFRA Good Laboratory Practice Guidelines 40 CFR 160. The method also passed an Independent Laboratory Validation (ILV) as per U.S. EPA FIFRA Subdivision N.
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PMID:Analytical method for the determination of cyromazine and melamine residues in soil using LC-UV and GC-MSD. 1095 15

An efficient method was developed for the analysis of selected PCBs and PAHs in dry peat samples. The method includes a shaking extraction using acetone and hexane followed by the purification of the crude extract by gel permeation chromatography (GPC) which turned out to be the key clean-up step. The method was used to determine seven indicator PCBs and 16 EPA-PAHs in individual sections of an ombrotrophic peat core in south-west Switzerland. The maximum concentrations of PCBs (19 microg sigma PCBs/kg dm) were found at a peat depth of 10-15 cm which is estimated to correspond to a time period of 1976-1960 whereas the PAH profile showed a maximum (2853 microg sigma PAHs/kg dm) at a depth of 20-25 cm which represents circa 1951-1930. Compared to these maxima, the concentrations of PAHs in the top layer (1990-1986) are six times lower, but the decline in PCBs is only 38%. The concentration profiles are generally consistent with known changes in contaminant emissions, and suggest that more detailed studies of ombrogenic peat bog profiles could be used for detailed reconstructions of the changing atmospheric fluxes of these and other organic contaminants.
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PMID:Concentrations and distribution of some polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) in an ombrotrophic peat bog profile of Switzerland. 1128 17

The following four methods were compared on the extraction efficiency of 16 EPA (US Environmental Protection Agency) polycyclic aromatic hydrocarbons (PAHs): German method of the Verband Deutscher Landwirtschaftlicher Untersuchungs und Forschungsanstalten (VDLUFA), two methods of the International Organization for Standardization using shaking (ISO A) and Soxhlet extraction (ISO B) and an ultrasonic method. Recovery rates of 16 PAHs were determined in two soils. Extraction efficiency was evaluated in five soils and three sediments. Effect of drying soils and sediments on extraction efficiency was tested using the VDLUFA and the ultrasonic methods. Our study shows that the number of aromatic rings, rather than extraction procedures, significantly influenced recovery rates of individual PAHs. No significant differences in extraction efficiency of the four methods were observed for less polluted samples. For highly polluted soils, extraction efficiency decreased in the following order: VDLUFA method > ISO A > ultrasonic method > ISO B. Influence of soil moisture on extraction efficiency depended to some extent on both solvent used and content of PAHs in samples. A mixture of dichloromethane/acetone (5:1) is recommended for PAH extraction from moist samples when the ultrasonic method is used.
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PMID:Comparative study of extraction methods for the determination of PAHs from contaminated soils and sediments. 1222 95

There are differences between the EPA Method 365 and the APHA-AWWA-WEF's Standard Method 4500 with respect to the post-digestion treatment procedures of the persulfate-digested water. The effects on total phosphorus analysis of different post-digestion treatment procedures, such as neutralization and reacidification, and shaking/settling, were investigated in this study using the total phosphorus measurements of water samples from the Everglades Round Robin (ERR) study and comparing the results with the ERR study. The effects of the insoluble particles or phosphorus adsorption/precipitation on/with Al and Fe hydroxides in different post-digestion treatment procedures adequately accounted for the differences between the most probable value and the higher or lower total phosphorus measurements reported in the ERR study. Based on the results of this investigation we recommend that a clearly defined set of digestion and post-digestion treatment procedures be adopted as the standard for total phosphorus analysis using the ascorbic acid method.
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PMID:The effects of post-persulfate-digestion procedures on total phosphorus analysis in water. 1538 Sep 79

A liquid chromatographic (LC) method for the analysis of lasalocid sodium in premixes, complete animal feeds, and trace-level feeds was collaboratively studied. The method employs a 0.5% HCI acidified methanol extraction followed by 20 min sonication in a water bath heated to 40 degrees C. Samples are then shaken on a mechanical shaker for 1 h and stored overnight, followed by an additional 10 min shaking the following morning. Sample extracts are diluted if necessary with extractant, filtered, and injected onto an LC system. Determination of all lasalocid homologs is by reversed-phase LC with fluorescence detection at 314 nm excitation and 418 nm emission. Eight samples of drug premixes, medicated feeds, and mineral supplements, along with 2 samples for trace-level analysis were sent to 20 collaborators in the United States, Canada, and The Netherlands. Study data were returned by 17 laboratories. Two additional supplemental trace-level samples and a blank feed were provided to 15 of the collaborating laboratories, and test data were received from all 15 participants. For the drug premixes, medicated feeds, and mineral supplements, RSDr values (within-laboratory repeatability) ranged from 1.2 to 19.9%, RSDR values (among-laboratory reproducibility) ranged from 3.4 to 32.3%, and HorRat values ranged from 0.35 to 3.73. For the trace-level samples, only lasalocid A, the predominant homolog comprising > 90% of the sum of all homolog peak area, was quantified. All laboratories correctly identified the analyte. Although some instrument response was reported by a number of laboratories for the blank feed, all but one laboratory's results were well below the 1 mg/kg limit of quantification. RSDr values for the initial 2 trace-level samples were excessive, ranging from 51.6 to 64.4%. RSDR values ranged from 51.6 to 75.7%, and HorRat values ranged from 3.6 to 4.0. Data for the initial trace-level samples indicated that the test samples were improperly prepared to ensure homogeneity, and a new set of supplemental samples was provided to collaborators, with significantly improved results. RSDr values for the 2 supplemental trace-level samples ranged from 1.6 to 2.5%, RSDR values ranged from 5.6 to 9.2%, and HorRat values ranged from 0.43 to 0.62.
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PMID:Determination of lasalocid sodium in animal feeds and premixes by reversed-phase liquid chromatography: collaborative study. 1856 91

Low concentrations (microg/L) of the perchlorate anion, ClO(4)(-), have been measured in surface and ground water supplies in many locations throughout the United States. Perchlorate is known to affect the function of the thyroid gland in mammals and its toxicity primarily results from its inhibition of thyroid hormone output. The major sources of perchlorate contamination in surface and ground waters are defense contractors, military installations, propellant manufacturers and agriculture. The currently accepted method of perchlorate analysis, recommended by the US EPA, is neither fast nor easy to use and requires purchase of an expensive high performance ion chromatograph (IC). The novel method described here uses dye resazurin to measure perchlorate reduction by bacterial cultures and bacterial consortia in a high-throughput, multi-well, culture plate format. The method is based on the observation that perchlorate reduction and the decrease of resazurin fluorescence occur simultaneously in perchlorate degrading cultures. The bioassays were performed in anaerobic serum bottles or 96-well plates with constant shaking, using a minimal ATCC medium with 10 mM acetate as electron donor/carbon source and 200 ppm perchlorate as an electron acceptor. Fluorescence measurements with excitation at 570 nm and emission at 590 nm were taken in 20 min intervals. Changes in perchlorate concentration were confirmed using IC. Based on the experimental data, a simple model showing the correlation between perchlorate concentration in microbial culture and resazurin fluorescence level was proposed. Other dyes including redox indicators, reactive azo dyes and electron shuttle chemicals were also tested for comparison and were found less useful.
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PMID:A method for assaying perchlorate concentration in microbial cultures using the fluorescent dye resazurin. 2010 1

An enzyme-linked immunosorbent assay (ELISA) for the quantitative determination of Aroclors 1242, 1248, 1254, and 1260 in soil and sediments was developed and its performance compared with that of gas chromatography (GC). The detection limits for Aroclors 1242 and 1248 in soil are 10.5 and 9 ng/g, respectively. The assay linear dynamic range is 50-1333 ng/g. Cross-reactivity of the assay with 37 structurally related potential cocontaminants in environmental soil samples was examined; none of the chlorinated anisoles, benzenes, or phenols exhibited >3% cross-reactivity, with <0.1% cross-reactivity being the norm. Soil spike recoveries of 107% and 104% were obtained for Aroclors 1242 and 1248, respectively, for a spike level of 5 mg/kg, with corresponding relative standard deviations of 14% and 17%. One hundred forty-eight environmental soil, sediment, and paper pulp samples, obtained from two EPA listed Superfund sites, were analyzed by ELISA and standard GC methods. Samples were extracted for ELISA analysis by shaking with methanol. Additional extractions of the same samples were performed either with supercritical carbon dioxide or by Soxhlet extraction with methanol. ELISA results for both the supercritical fluid and the Soxhlet extracts were in close agreement with the GC results, while the ELISA results for the methanol shake extracts were not. The data for the environmental samples demonstrated the capability of the ELISA to provide accurate results and reinforced the dependence of any detection method, including ELISA, on appropriate extraction procedures.
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PMID:Quantitative enzyme-linked immunosorbent assay for determination of polychlorinated biphenyls in environmental soil and sediment samples. 2161 32


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