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The drug impaired driver. Detection and forensic specimen analysis.

Whole blood samples were collected from arrested D. U. I. subjects in two locations, by the U. S. Park Police (USPP) in and around Washington, D. C. and through a suburban police department (MLMP), for the purpose of detecting illicit drug use. All blood samples were screened using an adapted Abuscreen RIA to non-urine (blood) procedure for the following drugs: THC, Cocaine, PCP, and Opiates. Forensic samples were confirmed through GC/MS. Results and characteristics of drug offenders are presented. It was found that 39 percent of sampled offenders from the MLMP showed measurable levels of cannabinoids. 9.5 percent of sampled offenders from the USPP showed measurable levels of Phencyclidine. Recommendations are made for the processing of suspected drug impaired drivers.

Adolescent↗

Genetic variation analysis in parkinson disease patients with and without hallucinations: case-control study.

BACKGROUND: Visual hallucinations in Parkinson disease (PD) occur in approximately one third of patients treated long-term with dopaminergic medications. In Alzheimer disease, hallucinations and psychosis have been linked to increased representations of B2/B2 homozyogotes for the dopamine receptor gene DRD1 and 1/1 or 2/2 homozygotes for DRD3. In addition, a previous study of PD patients with and without hallucinations did not show differences in D2 and D3 polymorphisms, although careful case-control matching was not performed. Another study linked the apolipoprotein E4 (APOE4) allele to hallucinations in PD. OBJECTIVE: To determine whether the frequency of dopamine receptor genetic variants and APOE alleles in patients with PD with and without chronic visual hallucinations resembles the pattern previously documented in patients with Alzheimer disease. METHODS: We conducted a case-control study of 44 patients with PD and chronic hallucinations and 44 patients with PD who had never hallucinated. Cases and controls were matched for current age and medications. DNA was isolated from blood samples and assayed for DRD1, DRD2, DRD3, DRD4, and APOE polymorphisms. Receptor polymorphisms were genotyped by polymerase chain reaction. Genotypes in hallucinators and nonhallucinators were compared using Mantel-Haenszel tests stratified by pair, and allele frequencies were compared using Wilcoxon signed rank tests within pairs. RESULTS: Neither D1 receptor genotypes (P =.37) nor allele frequencies (P =.38) differed, and there was no predominance of B2/B2 homozygotes in the hallucinators. For D3, there was a higher frequency of allele 2 (P =.047), but there was no significant difference between frequencies of homozygotes vs heterozygotes (P =.39) as reported in Alzheimer disease. D4 receptor distribution of long and short alleles did not differ between the 2 patient groups, and there were too few C alleles (3 of 86) to compare D2 allele genotypes or frequencies. For APOE, 12 cases and 12 controls carried E4 alleles (P>.99). CONCLUSIONS: With careful case-control matching, visual hallucinations in PD are not associated with the pattern seen for patients with Alzheimer disease and visual hallucinations. Furthermore, there was no association between hallucinations and APOE. Similar methods using larger sample sizes might be adapted to test whether specific dopaminergic receptor genetic variants are associated with visual hallucinations in PD. Based on our data, the DRD3 allele 2 may merit further study.

Aged↗

Studies of DNA damage and cell death in embryonic limb buds induced by teratogenic exposure to cyclophosphamide.

Many teratologic investigations have shown that certain types of chemical insults to the embryo (those altering replication, transcription, and translation) can cause excessive cell death in tissues destined to become malformed. Chemical carcinogens also induce cell death in target tissues, but the critical event is believed to be heritable alteration in the DNA of surviving cells. In the present study, an attempt was made to study the interaction between cell death and DNA damage in the initiation of birth defects. The pattern of DNA damage induced by cyclophosphamide was examined at time intervals before, during, and after the necrotic episode in mouse embryo limb buds. The alkaline elution assay was used to measure alkali-labile sites in single-strand DNA due to its adaptability to small tissue samples. An ip dose of 20 mg/kg of cyclophosphamide induced forelimb malformations in 85% of surviving mouse fetuses and 30% embryolethality when administered at 9 am on Day 11. As early as 5 hr after exposure, a slight excess of necrosis was observed in treated limbs by light microscopy, while at 24 hr, massive necrosis was evident. By 48 and 72 hr, excess necrosis was not observed in treated limbs. When alkaline elution analysis was conducted at prenecrotic (1-, and 5-hr), necrotic (24-hr), and postnecrotic (48-, and 72-hr) intervals, a trend toward increasing DNA damage in treated limbs with time was observed. The greatest differences in elution values occurred during the postnecrotic period. Although mean retention values were not significantly different, significantly increased variance was obtained in retention values of treated limbs at all time intervals other than 1 hr. This may reflect the actual in vivo situation where relatively few cells within a heterogeneous population of cells carry sublethal DNA damage into the postnecrotic period. These results suggest that not all limb bud cells affected by teratogenic exposure to cyclophosphamide die, but that some persist to the postnecrotic period carrying heritable alterations in their DNA.

Abnormalities, Drug-Induced↗

Determination of glutathione peroxidase activity in human milk.

An analytical method for determining glutathione peroxidase (GPx) (EC 1.11.1.9) activity in whole blood has been adapted to human milk samples. The values obtained for precision (relative standard deviation: 8.4%), linearity and accuracy (recovery: 90.4%) indicate the adequacy of the method for the mentioned purpose. The method was applied to 11 human milk samples obtained in the range from 6 to 135 days post partum. The resulting GPx activities (83.3 +/- 23.6 U/L) did not correlate to the selenium content of the samples, though a reciprocal correlation was found between the duration of lactation and milk GPx activity.

Female↗

Overview on community legislation in the field of official control of mycotoxins in feedingstuffs.

The Community legislation currently in force identifies a group of substances whose presence in feedingstuffs is undesirable. For each one of these substances, acceptable maximum levels have been fixed. The compliance with these levels in feedingstuffs must be checked by Community sampling and analysis methods. In the specific case of the aflatoxins, analytical methods, based on thin-layer chromatography (TLC) and high performance liquid chromatography (HPLC), have been adopted by directive. Another directive has established a general sampling method. The practice, however, has shown that it is not applicable to very large batches where the distribution of the contaminants is not homogeneous. A small group of experts of the Commission reached the conclusion that, in the future Community legislation, it will be appropriate: i) to divide the undesirable substances in two groups (substances with homogeneous and non-homogeneous distribution); ii) to adopt two different strategies for the cargoes "at risk" and "not at risk"; iii) to have methods of sampling, preparation, and analysis which are fast, reliable, easy to apply, and recognized at the international level. These experts proposed adaptations in the directive on "Sampling," in the case of large vessels, but suggested at the same time deferring any decision to the near future.

Aflatoxin B1↗

Factors indicative of outcome in a comparative trial of acyclovir and vidarabine for biopsy-proven herpes simplex encephalitis.

A total of 208 patients underwent brain biopsy for presumptive herpes simplex encephalitis and were randomized to receive either vidarabine, vira-A, at 15 mg/kg/day, or acyclovir, at 30 mg/kg/day for ten days. 69 patients (33%) had biopsy-proven disease; 37 received vira-A and 32 acyclovir. With the exception of age, patient populations were balanced for demographic characteristics. Overall survival for acyclovir recipients was 72% compared with 46% for vira-A-treated patients 18 months after therapy (p = 0.008). After adjustment for differences of age between treatment populations by multivariant regression analyses, acyclovir treatment remained superior to vidarabine therapy (p = 0.041). Mortality varied according to the level of consciousness at the onset of therapy. For lethargic, semicomatose and comatose patients, mortality was 42%, 46%, and 67%, respectively, for the vira-A-treated patients and 0%, 25% and 25%, respectively, for acyclovir-treated patients. Six months post-therapy morbidity assessments revealed five (14%) vira-A versus 12 (38%) acyclovir recipients who had returned to normal function, while eight (22%) and three (9%), respectively, had moderate debility. Outcome differences were significant (p = 0.02; Wilcoxon, 2-sample test) using an adapted scoring system. Age and Glasgow coma scale greater than 10 predicted the best outcome following acyclovir treatment. Disoriented patients who flex and respond by eye to pain had no mortality and 50% returned to normal. These data indicate that acyclovir is the treatment of choice for biopsy-proven herpes simplex encephalitis.

Acyclovir↗

Method for quantitating cholesterol in subfractions of serum lipoproteins separated by gradient gel electrophoresis.

Extensive heterogeneity in particle size distribution of serum lipoproteins of baboons was resolved by a procedure that combined Sudan black B prestaining, polyacrylamide gradient gel electrophoresis (GGE), and quantitative densitometry. Each densitometric scan represented a continuous distribution of the relative amount of cholesterol in a serum sample, as a function of the lipoprotein particle size. For analytical purposes, each scan was divided into 12 fractions, representing 12 particle size ranges. The relationship between the estimated cholesterol concentrations in the summed GGE/densitometric fractions corresponding to very low-density lipoproteins (VLDL) + low-density lipoproteins (LDL) and those corresponding to high-density lipoproteins (HDL) and concentrations measured by the heparin-Mn2+ precipitation/enzymatic procedure was linear over a broad range. However, a systematic overestimation of HDL cholesterol concentration and an underestimation of VLDL + LDL cholesterol concentration was apparent. Therefore, correction factors were developed for adjusting the estimates of VLDL + LDL and HDL cholesterol concentrations obtained by the GGE/densitometric method. This analytical method is rapid, repeatable, economical, and useful for genetic and dietary research in which cholesterol concentrations in multiple particle size ranges of lipoproteins must be measured in large numbers of samples. It also is adaptable to immunoblotting procedures for detecting the distribution of specific apolipoproteins among the size-resolved lipoproteins.

Centrifugation, Density Gradient↗

Changes in human skeletal muscle contractility and hormone status during 2 weeks of heavy strength training.

To examine neuromuscular and hormone changes during 2 weeks of heavy strength training, 18 weight-trained male students were recruited either into a heavy training group (HT, n = 11) or into a control group (Ctr, n = 7). The heavy training protocol consisted of leg-extensor workouts performed daily, while workouts were performed twice a week in the Ctr group. A test of one repetition maximum (1 RM) was performed before heavy training and on the 2nd day after heavy training. Isokinetic knee extensions, electrical stimulation, and squat jumps were performed before, on the 8th day of heavy training, and on the 4th day after heavy training. Morning blood samples (0800 hours) were drawn before, on the 8th day of heavy training, and on the 4th day after heavy training. Before, and on the 5th day after heavy training, 24 h urine samples were collected. The 1 RM leg press increased by 6 (SEM 2)% in the HT group. Testosterone and insulin-like growth factor-1 concentrations were respectively 12 (SEM 5)% and 11 (SEM 3)% lower than baseline on the 8th day of heavy training; however, hormone levels were back to baseline on the 4th day after heavy training. A significant correlation between individual changes in 1 RM leg press and changes in testosterone concentrations was observed in the HT group (r = 0.69). In the HT group, 24 h urinary catecholamine excretion increased by 26 (SEM 12)%, 3-methylhistidine excretion increased by 21 (SEM 6)% and creatinine excretion increased by 11 (SEM 5)%. There were no significant changes in the Ctr group. This work addresses the role of changes in basal hormone status (morning samples) for skeletal muscle adaptation to heavy strength training.

Adrenocorticotropic Hormone↗

Neural network mosaic model for pupillary responses to spatial stimuli.

A neural network mosaic model was developed to investigate the spatial-temporal properties of the human pupillary control system. It was based on the double-layer neural network model developed by Cannon and Robinson and the pupillary dual-path model developed by Sun and Stark. The neural network portion of the model received its input from a sensor array and consisted of a retina-like two-dimensional neuronal layer. The dual-path portion of the model was composed of interconnections of the neurons that formed a mosaic of AC transient and DC sustained paths. The spatial aggregates of the AC and DC signals were input to the AC and DC summing neurons, respectively. Finally, the weighted sum of the aggregate AC and DC signals provided the output for driving the pupillary response. An important property of the model was that it could adaptively learn from training samples by adjustment of the weights. The neural network mosaic model showed excellent performance in simulating both the traditional pupillary phenomena and the new spatial stimulation findings such as responses to change in stimulus pattern and shift of light spot. Moreover, the model could also be used for the diagnosis of clinical deficits and image processing in machine vision.

Brain Stem↗

Application of simultaneous determination of 3H, 14C, and 22Na by liquid scintillation counting to the measurement of cellular ion-transport.

A liquid scintillation counting method for simultaneous determination of three radioactive nuclides (3H, 14C, and 22Na) of biological interest was studied. By comparing the beta spectra of the three nuclides, their counting energy ranges, A, B, and C, were determined. 22NA was set high enough to avoid any spillover counts from lower-energy nuclides. Region A for 3H was set to maximize the counting efficiency. A good correlation between the counting efficiency for 22Na in region C and the counting efficiency of other nuclides in all regions was obtained. Prior to 3H and 14C dpm calculations, the 22Na counts spilled down in regions A and B were subtracted from the total counts in regions A and B. A simple linear equation was then used to compute 3H and 14C dpm. Findings show that the method presented is adaptable for highly quenched samples up to quenching indices of tSIE = 100. The method is useful for studying the biological transport coupled to Na+.

Beta Particles↗

Phase 1 and Phase 2 drug metabolism in isolated epidermal cells from adult hairless mice and in whole human hair follicles.

A sensitive fluorimetric assay to determine both Phase 1 (oxidation) and Phase 2 (conjugation) drug metabolism in epidermal cells isolated from hairless mice, using ethoxycoumarin as a model substrate, is described. Ethoxycoumarin was metabolized by isolated epidermal cells via dealkylation to 7-hydroxycoumarin (7-OHC) and subsequent conjugation. Phase 1 metabolites were extracted in ether from the aqueous incubation media, back extracted into sodium hydroxide and determined fluorimetrically. Conjugated metabolites remaining in the aqueous phase were hydrolysed by the action of beta-glucuronidase and extracted and determined in a similar manner. The production of free 7-OHC by isolated epidermal cells was biphasic at all substrate concentrations tested, exhibiting an initial linear increase followed by a plateau phase. The plateau phase was attributable to the conjugation of 7-OHC produced in situ. Metabolism was inhibited by SKF 525A, carbon monoxide, and alpha-naphthoflavone. Endogenous supplies of reducing equivalents in the form of NADPH were adequate to attain maximal rates of metabolism. With human hair follicles both Phase 1 and Phase 2 activity was detectable in 7 out of 11 subjects. The assay has the advantages of being sensitive, producing single defined metabolites from both Phase 1 and Phase 2 metabolism; is readily adaptable to human skin samples.

Animals↗

Coagulant and fibrinolytic activities in the leukemic cell lysates.

We attempted to examine procoagulant activity (PCA), X activator activity (XAA) and plasminogen activator activity (PlgAA) of various leukemic cell lysates: 17 acute myelocytic leukemias (AML), 4 acute promyelocytic leukemias (APL), 9 acute myelomonocytic leukemias (AMMoL), 7 chronic myelocytic leukemias (CML), 4 CML with blastic crisis, 7 T cell acute lymphocytic leukemias (ALL), 8 adult T cell leukemias (ATL), 8 null cell ALL, 6 B cell lymphocytic leukemias. Among those 70 cases, 4 APL, 4 AMMoL and 5 AML were associated with overt disseminated intravascular coagulation (DIC) and 5 T cell ALL, 7 ATL and 2 null cell ALL were associated with hypofibrinogenemia not adapted for DIC. The sample used was the lysate of 10(7) cells. PCA was measured by recalcification time of normal plasma with the cell lysate, XAA and PlgAA was measured by chromogenic substrate. APL and AML, especially those associated with overt DIC, had high PCA, and lymphocytic leukemia generally had low PCA in comparison with normal controls. Total PCA (PCA multiplied by cell count/microliter) was remarkably increased in DIC and mildly increased in ALL with hypofibrinogenemia. The change in XAA and total XAA (XAA multiplied by cell count/microliter) was not remarkable in any leukemia except for T cell ALL and null cell ALL with hypofibrinogenemia. PlgAA was high in lymphocytic leukemias with hypofibrinogenemia, APL and AMMoL with DIC. Total PlgAA (PlgAA multiplied by cell count/microliter) was high especially in T cell ALL and null cell ALL with hypofibrinogenemia. Thus it is probable that PCA is the most important factor causing DIC in myelogenous leukemia and that PlgAA is the most important factor causing hypofibrinogenemia in lymphocytic leukemia. The measurement of these activities in the leukemic cells is valuable in prediction and prevention of the hemostatic disorder in leukemia.

Cysteine Endopeptidases↗

Segmented force plate (SFP) software package for clinical use.

A gait analysis system is described. It is designed for clinical use as well as research purposes. The system is simple to operate and can be used by non-computer specialist. The design philosophy is straightforward and allows for easy adaptation to other systems. Samples of the output are presented.

Electronic Data Processing↗

Automatic visual field: a software diagnostic procedure.

A recently developed technique for the automatic acquisition of data on visual field losses was tested, with reliable neuro-ophthalmological parameters, on 300 subjects with and without eye disorders. Algorithms for acquisition and processing of the central visual field were implemented on an IBM-AT personal computer with standard peripherals. The contours of scotomata (visual field losses) were best estimated by probabilistic adaptive enhancement of data sampling in those areas with greater visual variability. Image processing tools were specially designed to extract information concerning the size, shape, position and number of scotomata in the visual field. The diagnosis of wider campimetric lesions required parameters such as symmetry or specularity coefficients, obtainable by analysing the visual field of both eyes. Data obtained were correlated to the pathology involved by univariate statistical tools.

Algorithms↗

Assessment of infection control programs in Maryland skilled-nursing long-term care facilities.

BACKGROUND: Nosocomial infections cause substantial morbidity and mortality among residents in long-term care facilities (LTCFs). Although infection control programs now exist in many LTCFs in the United States, little has been published regarding the effectiveness of these programs. The 1976 Centers for Disease Control and Prevention Study on the Efficacy of Nosocomial Infection Control (SENIC) established the effectiveness of infection control programs in acute care facilities. However, a limitation of that study was the exclusion of LTCFs. METHODS: The purpose of this pilot study was to assess infection control programs in LTCFs through the use of an Infection Surveillance and Control Questionnaire adapted from SENIC. The sample consisted of 123 skilled-nursing LTCFs in the State of Maryland. The questionnaire was completed by the person responsible for infection control activities in each LTCF. RESULTS: Results of the study show the following: (1) an upward trend in infection control activity in Maryland LTCFs, with the majority having medium activity, and (2) an estimated overall prevalence rate of infection of 4% on the basis of total resident census. CONCLUSION: The findings indicated that the Infection Surveillance and Control Questionnaire is a reliable instrument to assess infection control programs in LTCFs. A nationwide study is planned to examine the relationship between infection control activity and the risk of nosocomial infection among skilled-nursing LTCFs throughout the United States.

Aged↗

Solid-phase extraction and direct high-performance liquid chromatographic determination of metoprolol enantiomers in plasma.

A method is described by which underivatized metoprolol enantiomers in plasma can be quantitated by high-performance liquid chromatography with fluorescence detection. Samples are prepared for injection using a simple solid-phase extraction procedure which is essentially 100% efficient for all analytes. The metoprolol enantiomers are resolved using a cellulose tris(3,5-dimethylphenylcarbamate) chiral stationary phase and a hexane-ethanol-diethylamine mobile phase. Samples were tested for adaptability to autoinjection and found to be stable for at least 16 h after reconstitution in mobile phase. The automated method was determined to be precise and accurate for enantiomer concentrations as low as 10 ng base per ml and was successfully employed in a pharmacokinetic investigation.

Chromatography, High Pressure Liquid↗

Rigidity and bradykinesia reduce interlimb coordination in Parkinsonian gait.

OBJECTIVE: To assess the influence of rigidity and bradykinesia and the extent of dopaminergic degeneration on interlimb coordination during walking in early, drug-naive patients with Parkinsons disease (PD). DESIGN: The interlimb coordination was examined during a systematic manipulation of walking speed on a treadmill. The phase relations between arm and leg movements were related to the clinical measures of rigidity and bradykinesia as well as to the extent of dopaminergic degeneration. SETTING: Movement disorders outpatient clinic (including motion analysis laboratory) and a nuclear medicine department of a university hospital. PARTICIPANTS: Twenty-nine early and drug-naive PD patients. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: The interlimb coordination during walking was evaluated by studying the (continuous) relative phase relations between movements of arms and legs. The clinical assessment of rigidity and bradykinesia was performed by using the Unified Parkinson Disease Rating Scale. The dopaminergic degeneration was expressed as striatal 2beta-carboxymethoxy-3beta-(4-iodophenyl) tropane (beta-CIT) single-photon emission computed tomography (SPECT) binding. RESULTS: The mean relative phase between arm and leg movements increased significantly with walking speed in all patients. Significant correlations were found between the rigidity and bradykinesia and the coordination measures ( P </=.007), as well as contralateral striatal [ 123 I]beta-CIT SPECT binding and coordination measures ( P <.001), in terms of asymmetry indices. CONCLUSIONS: Early, drug-naive PD patients in this sample were able to adapt their coordination patterns when walking speed was systematically manipulated. However, bradykinesia and rigidity as well as the extent of degeneration of the dopaminergic system were associated with a limited adaptive ability (flexibility) in movement coordination. The combination of a drug treatment that controls bradykinesia and rigidity and a physical therapy exercise programs possibly using external cues mechanisms are required to obtain relevant effects on gait in PD patients.

Adult↗

Concurrent and discriminant validity of the Stunkard's figure rating scale adapted into Portuguese.

This study examined the concurrent and discriminant validity of the Figure Rating Scale adapted into Portuguese. The sample was composed of a control group (98 students without eating disorders) and a clinical group (16 women diagnosed with Bulimia Nervosa). Respondents chose schematic figures representing their current and ideal body sizes. The difference between the two choices was calculated to give an ideal discrepancy score. There were high correlations between body mass index and current body size or ideal discrepancy score. The ideal discrepancy scores were greater among the clinical group, indicating that the scale could discriminate between the two groups. The results of this preliminary work indicate that the scale is a valid measure of body image when used in Brazil.

Adult↗