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PubMed1980

Gustafson's method for age determination from teeth--a modification for the use of dentists in identification teams.

Gustafson's method for age determination from teeth is based on the evaluation of ground sections of teeth. Six age-associated parameters are evaluated in the ground section and are compared to a regression curve of age versus the age-associated changes. Two of these changes, transparency of radicular dentin and secondary dentin, have the highest correlation with age. The evaluation of these parameters only from thin (0.25-mm) ground sections may lead to an artificially high "secondary dentin value." These artifacts may be caused by the attempt to include the whole pulp chamber and root canal in a 0.25-mm-thick ground section and by an accidental overgrinding of the apical area of the root, respectively. These artifacts were encountered occasionally even in ground sections prepared by highly trained personnel and became more frequent in ground sections prepared by a person who, though trained, did not use this technique daily. A modification of the data-collecting method is suggested to make possible the use of thick (1.0-mm) ground sections for the evaluation of most of the aging criteria, thereby eliminating the possible inaccuracies in the preparation and evaluation of the thin (0.25-mm) ground sections.

Age Determination by Teeth↗
PubMedDate not supplied

Visual cortex neurons in monkeys and cats: detection, discrimination, and identification.

A descriptive function method was used to measure the detection, discrimination, and identification performance of a large population of single neurons recorded from within the primary visual cortex of the monkey and the cat, along six stimulus dimensions: contrast, spatial position, orientation, spatial frequency, temporal frequency, and direction of motion. First, the responses of single neurons were measured along each stimulus dimension, using analysis intervals comparable to a normal fixation interval (200 ms). Second, the measured responses of each neuron were fitted with simple descriptive functions, containing a few free parameters, for each stimulus dimension. These functions were found to account for approximately 90% of the variance in the measured response means and response standard deviations. (A detailed analysis of the relationship between the mean and the variance showed that the variance is proportional to the mean.) Third, the parameters of the best-fitting descriptive functions were utilized in conjunction with Bayesian (optimal) decision theory to determine the detection, discrimination, and identification performance for each neuron, along each stimulus dimension. For some of the cells in monkey, discrimination performance was comparable to behavioral performance; for most of the cells in cat, discrimination performance was better than behavioral performance. The behavioral contrast and spatial-frequency discrimination functions were similar in shape to the envelope of the most sensitive cells; they were also similar to the discrimination functions obtained by optimal pooling of the entire population of cells. The statistics which summarize the parameters of the descriptive functions were used to estimate the response of the visual cortex as a whole to a complex natural image. The analysis suggests that individual cortical neurons can reliably signal precise information about the location, size, and orientation of local image features.

Animals↗
PubMed2000

Correlations between physiological parameters and performance in elite ten-pin bowlers.

The increasing acceptance of ten-pin bowling as a sport, as well as the keen competition amongst bowlers, necessitates the identification of performance indicators to aid training. The aim of this cross-sectional study was to determine if age, height, weight, aerobic power index, bowling grip strength, 10-RM leg press performance, and the sit-and-reach distance correlated with bowling performance in 42 elite bowlers (26 males and 16 females). At the same time, the physiological profiles of bowlers classified as heavy ball strokers, heavy ball crankers, and light ball spinners were compared. The results showed that for the male bowlers, none of the parameters correlated with performance, while for the female bowlers, the only parameter that correlated with performance was the aerobic power index. Bowlers using the three different releases had similar anthropometric and physiological profiles. The implications from this study are that bowlers of diverse age and build can be equally competitive in the sport; that aerobic capacity (as reflected by the aerobic power index) may, to a certain extent, contribute to bowling performance; and that strength and flexibility measures do not seem to be useful performance indicators amongst elite bowlers.

Adult↗
PubMed2005

Determination of denaturated proteins and biotoxins by on-line size-exclusion chromatography-digestion-liquid chromatography-electrospray mass spectrometry.

A multidimensional analytical method for the rapid determination and identification of proteins has been developed. The method is based on the size-exclusion fractionation of protein-containing samples, subsequent on-line trypsin digestion and desalination, and reversed-phase high-performance liquid chromatography-electrospray mass spectrometry detection. The present system reduces digestion times to 20 min and the total analysis time to less than 100 min. Using bovine serum albumin and myoglobin as model proteins, optimization of key parameters such as digestion times and interfacing conditions between the different pretreatment steps was performed. The automated system was tested for the identification of infectious disease agents such as cholera toxin and staphylococcal enterotoxin B. This resulted typically in a positive identification by a total sequence coverage of approximately 40%.

Amino Acid Sequence↗
PubMed2004

Predicting human drug glucuronidation parameters: application of in vitro and in silico modeling approaches.

Cytochrome P450 (CYP) and UDP-glucuronosyltransferase (UGT), which both exist as enzyme "superfamilies," are together responsible for the metabolism of most hepatically cleared drugs. There is currently intense interest in the development of techniques that permit identification of the CYP and UGT isoform(s) involved in the metabolism of a newly discovered drug, and hence prediction of factors likely to alter elimination in vivo. In addition, the quantitative scaling of kinetic parameters for a metabolic pathway assumes importance for identifying newly discovered drugs with undesirable in vivo pharmacokinetic properties. Although qualitative and quantitative in vitro-in vivo correlation based on data generated using human liver tissue or recombinant enzymes have been applied successfully to many drugs eliminated by CYP, these strategies have proved less definitive for glucuronidated compounds. Computational (in silico) modeling techniques that potentially provide a facile and economic alternative to the in vitro methods are now emerging. This review assesses the utility of in vitro and in silico approaches for the qualitative and quantitative prediction of drug glucuronidation parameters and the challenges facing the development of generalizable models.

Cytochrome P-450 Enzyme System↗
PubMed2005

Application of graph theory: prediction of glycogen synthase kinase-3 beta inhibitory activity of thiadiazolidinones as potential drugs for the treatment of Alzheimer's disease.

The relationship of Wiener's index, a distance-based topological descriptor; Zagreb group parameter, M(1), an adjacency-based topological descriptor and eccentric connectivity index,an adjacency-cum-distance based topological descriptor with the glycogen synthase kinase-3 beta inhibitory activity of thiadiazolidinones has been investigated. A training set comprising 28 analogues of substituted thiadiazolidinones was selected for the present investigations. The values of the Wiener's index, Zagreb group parameter, and eccentric connectivity index for each of 28 analogues comprising the data set were computed. Resulting data was analyzed and suitable models developed after identification of active ranges. Subsequently, biological activity was predicted for each analogue involved in the data set using these models, which was then compared with the reported glycogen synthase kinase-3 beta inhibitory activities. Accuracy of prediction was found to vary from a minimum of approximately 83% for model based on Zagreb group parameter to a maximum of approximately 87% for model based on Wiener's index.

Alzheimer Disease↗
PubMed2003

Direct identification of all oncogenic mutants in KRAS exon 1 by cycling temperature capillary electrophoresis.

Over the past few decades, advances in genetics and molecular biology have revolutionized our understanding of cancer initiation and progression. Molecular progression models outlining genetic events have been developed for many solid tumors, including colon cancer. Previous reports in the literature have shown a relationship between different KRAS mutations and prognosis and response to medical treatment in colon cancer patients. Furthermore, the presence of a mutated KRAS has been correlated with different clinicopathological variables including age and gender of patients and tumor location. To our knowledge, few institutions screen for KRAS mutations on regular basis in colon cancer patients despite such evidence that knowledge of KRAS exon 1 status is informative. Here, we report on a mutation analysis method adapted to a 96-capillary electrophoresis instrument that allows identification of all 12 oncogenic mutations in KRAS exon 1 under denaturing conditions. To determine the optimal parameters, a series of DNA constructs generated by site-directed mutagenesis was analyzed and the migration times of all mutant peaks were measured. A classification tree was then made based on the differences in migration time between the mutants and an internal standard. A randomized series of 500 samples constructed with mutagenesis as well as 60 blind samples from sporadic colon carcinomas was analyzed to test the method. No wild-type samples were scored as mutants and all mutants were correctly identified. Post polymerase chain reaction (PCR) analysis time of 96 samples was performed within 40 min.

Base Sequence↗
PubMed2006

Regulator of G-protein signaling (RGS) proteins differentially control chondrocyte differentiation.

Control of chondrocyte differentiation is attained, in part, through G-protein signaling, but the functions of the RGS family of genes, well known to control G-protein signaling at the Galpha subunit, have not been studied extensively in chondrogenesis. Recently, we have identified the Rgs2 gene as a regulator of chondrocyte differentiation. Here we extend these studies to additional Rgs genes. We demonstrate that the Rgs4, Rgs5, Rgs7, and Rgs10 genes are differentially regulated during chondrogenic differentiation in vitro and in vivo. To investigate the roles of RGS proteins during cartilage development, we overexpressed RGS4, RGS5, RGS7, and RGS10 in the chondrogenic cell line ATDC5. We found unique and overlapping effects of individual Rgs genes on numerous parameters of chondrocyte differentiation. In particular, RGS5, RGS7, and RGS10 promote and RGS4 inhibits chondrogenic differentiation. The identification of Rgs genes as novel regulators of chondrogenesis will contribute to a better understanding of both normal cartilage development and the etiology of chondrodysplasias and osteoarthritis.

Animals↗
PubMed1991

Efficient analysis of protein 2D NMR spectra using the software package EASY.

The program EASY supports the spectral analysis of biomacromolecular two-dimensional (2D) nuclear magnetic resonance (NMR) data. It provides a user-friendly, window-based environment in which to view spectra for interactive interpretation. In addition, it includes a number of automated routines for peak-picking, spin-system identification, sequential resonance assignment in polypeptide chains, and cross peak integration. In this uniform environment, all resulting parameter lists can be recorded on disk, so that the paper plots and handwritten notes which normally accompany manual assignment of spectra can be largely eliminated. For example, in a protein structure determination by 2D 1H NMR, EASY accepts the frequency domain datasets as input, and after combined use of the automated and interactive routines it can yield a listing of conformational constraints in the format required as input for the calculation of the 3D structure. The program was extensively tested with current protein structure determinations in our laboratory. In this paper, its main features are illustrated with data on the protein basic pancreatic trypsin inhibitor.

Algorithms↗
PubMed1994

Effect of different combinations of antibiotics on experimental septic peritonitis in rabbits.

This study was undertaken to evaluate the efficacy of different combinations of antimicrobial agents in the treatment of experimental septic peritonitis. Two hundred rabbits, divided into ten groups of 20 rabbits each, were used. Septic peritonitis was provoked in two stages: treatment of animals by mechanical lavage or antibiotics was performed during the first stage; blood cultures, isolation and identification of aerobic and anaerobic bacteria in the peritoneal cavity were performed during the second stage. The parameters assessed were survival and, in the second phase, the formation of peritoneal abscesses. The most significant finding was noted in the first phase, where diffuse peritonitis took place, with a very high mortality rate due to bacteremia and sepsis. In both blood and pus from the peritoneal cavity cultures in all groups, Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis (among the aerobes) and Bacteroides fragilis, Clostridium sp. and Peptostreptococcus sp. (among anaerobes) were the predominant pathogens identified. High mortality rates appeared to be due to the aerobic microbes, particularly Escherichia coli, whereas abscess formation was related to the anaerobes, particularly Bacteroides fragilis. All antibiotics tested were effective, whether alone or in combination. Metronidazole, however, was the most effective in the reduction of intraabdominal abscesses. The lowest mortality rate was observed in animals injected with piperacillin and a combination of cefoxitin and an aminoglycoside with metronidazole. Finally, good peritoneal lavage seemed to be as effective as any combination of antibiotic treatment.

Animals↗
PubMed2004

Clinical characteristics of 5 Chinese LQTS families and phenotype-genotype correlation.

In order to assess the clinical manifestations and electrocardiogram (ECG) characteristics of Chinese long QT syndrome (LQTS) patients and describe the phenotype-genotype correlation, the subjects from 5 congenital LQTS families underwent clinical detailed examination including resting body surface ECG. QT interval and transmural dispersion of repolarization (TDR) were manually measured. Five families were genotyped by linkage analysis (polymerase chain reacting-short tandem repeat, PCR-STR). The phenotype-genotype correlation was analyzed. Four families were LQT2, 1 family was LQT3. Twenty-eight gene carriers were (14 males and 14 females) identified from 5 families. The mean QTc and TDRc were 0.56 +/- 0.04 s (range 0.42 to 0.63) and 0.16 +/- 0.04 s (range 0.09 to 0.24) respectively. 35.7% (10/28) had normal to borderline QTc (< or = 0.460 s). There was significant difference in QTc and TDRc between the patients with symptomatic LQTS and those with asymptomatic LQTS, and there was significant difference in TDRc between the asymptomatic patients and normal people also. A history of cardiac events was present in 50% (14/28), including 9 with syncope, 2 with sudden death (SD) and occurred in the absence of beta-blocker. Three SDs occurred prior to the diagnosis of LQTS and had no ECG record. Two out of 5 SDs (40%) occurred as the first symptom. Typical LQT2 T wave pattern were found in 40% (6/15) of all affected members. The appearing-normal T wave was found in one LQT3 family. Low penetrance of QTc and symptoms resulted in diagnostic challenge. ECG patterns and repolarization parameters may be used to predict the genotype in most families. Genetic test is very important for identification of gene carriers.

Arrhythmias, Cardiac↗
PubMed2005

Functional electrostimulation of muscles as a method for restoring motor functions.

The main functions of a method of functional electrical stimulation of muscles (FES) are described: diagnostic, prognostic, and therapeutic. The main indication for using the FES method is a deficiency of muscle function, which may be organic (due to lesions to neuromuscular structures) or functional (associated with relaxation of the muscular apparatus). The five most significant functions of the FES method were established: 1) identification of correctable movements and stimulable muscles; 2) identification of the amplitude and time program for stimulation; 3) stimulation regimes for pathological gaits; 4) stimulation parameters; 5) positioning of skin electrodes on the human body. Using the example of two severe central nervous system pathologies (spinal cord lesions in the lumbosacral area and hemiparesis of cerebral origin), the positive effects of FES on the process of motor rehabilitation of this category of patients were demonstrated.

Adult↗
PubMed2006

Analysis of in vitro skin permeation of 22-oxacalcitriol having a complicated metabolic pathway.

PURPOSE: The purpose of this study is to analyze simultaneous skin permeation and metabolism of 22-oxacalcitriol (OCT) having several metabolites in skin by observing skin permeation of only unchanged OCT through excised rat skin. METHODS: A diffusion model including metabolic processes was employed to express simultaneous skin permeation and metabolism of OCT. In vitro permeation experiments of OCT from Oxarol ointment through full-thickness and stripped rat skin were carried out using Franz-type diffusion cells. Time courses of unchanged OCT amounts in ointment, skin, and receptor fluid were determined and fitted to diffusion equations to obtain permeation parameters and a metabolic rate. RESULTS: Fitting curves of the skin permeation profile obtained by the model were sufficiently close to observed data of unchanged OCT amounts in ointment, skin, and receptor fluid. The following parameters were obtained: metabolic rate of 1.37 x 10(-1) h(-1), and diffusion constants of OCT in stratum corneum (SC) (D(SC)) and viable epidermis and dermis (VED) (D(VED)) of 1.50 x 10(-7) and 2.96 x 10(-4) cm2/h, respectively. The partition coefficient of OCT for SC/ointment (K(SC/D)) was 7 times greater than that of VED/ointment (K(VED/D)). CONCLUSIONS: The present analysis made it possible to calculate skin permeation parameters (partitioning, diffusivity, and metabolic rate) of OCT without requiring metabolic information, e.g., quantification of metabolites or identification of metabolic pathways. This would be widely applicable for drugs that are not suitable for conventional methods due to complicated metabolic pathways.

Algorithms↗
PubMed1990

Levels of eighteen non-conjugated and conjugated steroids in human breast cyst fluid: relationships with cyst type.

The present study investigates the levels of a large series of 18 non-conjugated or conjugated steroids in 71 samples of human breast cyst fluid (BCF) as divided into three groups corresponding to different electrolyte composition. In the type 1 group, the K+/Na+ ratio was higher than 1.5, while in type 2 it was lower than 0.66 and finally type 3 had an intermediate ratio. Pregnenolone (PREG) and progesterone (PROG) levels were approximately 2-fold higher (P less than 0.05) in the type 2 than in the type 1 group while both 17-OH-pregnenolone (17-OH-PREG) and 17-OH-progesterone (17-OH-PROG) concentrations were similar in these two groups. Most of the C-19 steroids analyzed, namely dehydroepiandrosterone sulfate (DHEAS), androst-5-ene-3 beta, 17 beta-diol (5-ene-DIOL), testosterone (TESTO), dihydrotestosterone (DHT), androstane-3 alpha, 17 beta-diol (3 alpha-DIOL), androsterone (ADT), androstane-3 alpha, 17 beta-diol glucuronide (3 alpha-DIOL-G) and androsterone glucuronide (ADT-G) were 180-360% (P less than 0.05) higher in type 1 than in type 2 cysts while no difference in C-18 steroid and C-18 steroid glucuronide levels was observed. A small or no difference was seen in steroid levels between types 2 and 3. We conclude that the arbitrary division according to the electrolyte composition of BCF permits identification of different patterns of steroid concentrations in BCF. However, the mechanism responsible for both sets of parameters remain unclear.

Adult↗
PubMed2004

Identification, characterization, and site-directed mutagenesis of recombinant pentachlorophenol 4-monooxygenase.

In a previous study, we constructed a three-dimensional (3D) structure of pentachlorophenol 4-monooxygenase (PcpB). In this study, further analyses are performed to examine the important amino acid residues in the catalytic reaction by identification of the proteins with mass spectrometry, circular dichroism (CD) and UV spectrometry, and determination of kinetic parameters. Recombinant histidine-tagged PcpB protein was produced and shown to have a similar activity to the native protein. Mutant proteins of PcpB were then produced (F85A, Y216A, Y216F, R235A, R235E, R235K, Y397A and Y397F) on the basis of the proposed 3D structure. The CD spectra of the proteins showed that there were no major changes in the structures of the mutant proteins, with the exception of R235E. Steady-state kinetics showed a 20-fold reduction in k(cat)/K(m) and a ninefold increase in K(m) for Y216F and a threefold reduction in k(cat)/K(m) and a sixfold increase in K(m) for Y397F compared to the wild type. On the other hand, the value of k(cat)/K(m) of R235K mutant was the same as that of wild type. As a result, it was confirmed that Y216 and Y397 play an important role with respect to the recognition of the substrate.

Amino Acid Substitution↗
PubMed2005

Nutritional assessment and management in hospitalised patients: implication for DRG-based reimbursement and health care quality.

INTRODUCTION: Malnutrition is associated with a higher morbidity resulting in an increased need for medical resources and economic expenses. In order to ensure sufficient nutritional care it is mandatory to identify the effect of malnutrition and nutritional care on direct cost and reimbursement. The primary aim of this study was to evaluate the economic effect of a nutritional screening procedure on the identification and coding of malnutrition in the G-DRG system. METHODS: All G-DRG relevant parameters of 541 consecutive patients at a gastroenterology ward were documented. Moreover, all patients were screened for malnutrition by a dietician according to the subjective global assessment (SGA). Patients were then grouped into the appropriate G-DRG and the effective cost weight (CW) was calculated. RESULTS: Ninety-two of 541 patients (19%) were classified malnourished (SGA B or C). Recognition of malnutrition increase from 4% to 19%. Malnourished patients exhibited a significantly increased length of hospital stay (7.7+/-7 to 11+/-9, P<0.0001). In 26/98 (27%) patients, the coding of malnutrition was considered relevant by grouping and resulted in a rise of DRG benefit. Mean case mix value and patients' complexity and comorbidity level (PCCL) increased after including malnutrition in the codification (CV 1.53+/-2.9 to 1.65+/-2.9, P=0.001 and PCCL 2.69+/-1.4 to 3.47+/-0.82, P<0.0001). The reimbursement increase by 360/malnourished patient or an additional reimbursement of 35280 (8.3% of the total reimbursement for all patients of 423186). Nutritional support in a subgroup of 50 randomly selected patients resulted in additional costs of 10268 . Forty-four of these patients (86%) were classified malnourished (32 SGA B and 12 SGA C). However, the subsequent reimbursement covered only approximately 75% of the expenses (7869), but did not include the potential financial benefits resulting from clinical interventions. CONCLUSION: Malnourished patients can be detected with a structured assessment and documentation of nutritional status and this is partly reflected in the G-DRG/ICD 10 system. In addition to increasing direct health care reimbursement, nutritional screening and intervention has the potential to improve health care quality.

Comorbidity↗
PubMed2005

Characterizing process effects on pharmaceutical solid forms using near-infrared spectroscopy and infrared imaging.

Near-infrared spectroscopy (NIRS) has become a widely used analytical technique in the pharmaceutical industry, serving for example to determine the active substance or water content of tablets. Its great advantage lies in the minimal sample preparation required and speed of measurement. In a study designed to detect the effects of process on tablet dissolution, we describe the application of NIRS to the detection and identification of changes in uncoated and coated tablets in response to pilot-scale changes in process parameters during melt granulation, compression, and coating. Beginning with a qualitative comparison between pharmaceutical batches, we show that NIRS and principal component analysis can separate batches produced with different melt granulation parameters and differentiate between cores compressed with different compaction forces. Complementary infrared imaging can also explain the difference in dissolution properties between samples produced with different melt granulation parameters. NIRS is sensitive to changes in coating formulation, the quality of a coating excipient (hydroxypropyl methylcellulose), and coating time. In a concluding quantitative analysis, we demonstrate the feasibility of NIRS in a manufacturing context for predicting coating time and detecting production cores failing to meet dissolution test specifications.

Cellulose↗
PubMed2006

Home and hospital monitoring for ALTE.

Apparent life-threatening events (ALTE) results from various causes. Documented monitoring of cardiorespiratory parameters and Hb-O(2) saturation by pulse oximetry (SpO(2)) has proven useful in the identification of significant events both in hospital and at home. Home monitoring might be especially helpful for infants with recurrent but infrequent clinical events not captured during a hospital admission.

Follow-Up Studies↗