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At least 127 records · Page 7Linked to original sources

PubMed2000

Prediction of crude fat content of longissimus muscle of beef using the ratio of fat area calculated from computer image analysis: comparison of regression equations for prediction using different input devices at different stations.

Crude fat content of longissimus (ribeye) muscle of beef cattle was predicted from a ratio of fat area (RFA) to area of ribeye muscle calculated from computer image analysis (CIA). Cross sections of 64 ribeyes taken from the 6-7th rib from cattle at experiment station A and cross sections of 94 ribeyes taken from the 6-7th rib from cattle at Experiment Station B were used in this study. Slices (1 to 1.5 cm in thickness) of just the Longissimus dorsi were homogenized and sampled for chemical estimation of crude fat content using petroleum ether. Crude fat content as determined from chemical analysis was used as the true estimate of fat content. A CCD (charge-coupled device) camera was used as the input device at Experiment Station A, and a single-lens reflex camera was used at Experiment Station B to photograph ribeyes for CIA. The contour comparison method, which assigns a threshold value for each marbling particle, was used to obtain accurate binarization in this study. Minimum and maximum of chemical measurements of crude fat were 2.1 and 39.8%, and for CIA calculation of the RFA were 6.1 and 56.8%, respectively. This range covered almost the complete range of the beef marbling standard used in carcass grading in Japan. The equation for the regression of the crude fat content (Y) on RFA (X) calculated from CIA for all of the data was Y = .793X-3.04 with r2 = .96. Regression equations for prediction of crude fat percentage from RFA taking into consideration the effect of experiment station were Y = .741X-2.22 with r2 = .91 for Experiment Station A, and Y = .782X-2.54 with r2 = .91 for Experiment Station B. Analysis of covariance showed that the effects of experiment stations on intercepts and slopes were not significant (P > .10). The ranges of differences between actual and predicted crude fat content from the prediction equation that was calculated without consideration of the effect of station were -6.4 to 4.0%. CIA of cross sections of the ribeye muscle seems to have potential for prediction of crude fat content.

Adipose Tissue↗

PubMed1998

Predicting performance on text: delayed versus immediate predictions and tests.

Delayed judgments of learning for word pairs are more accurate than immediate judgments of learning when the memory test is delayed. In the present experiment, I investigated a similar paradigm with text. Participants predicted performance on texts either immediately after reading the texts or after a delay following the reading of other texts, and tests were given either immediately or after a delay. Immediate ratings with an immediate test produced the most accurate predictions, and immediate ratings with a delayed test produced less accurate predictions. Delaying both the ratings and the test did not produce more accurate predictions than immediate predictions and a delayed test. The results for delayed judgments of learning with text were different from those with word pairs.

Analysis of Variance↗

PubMed2003

Prediction of prokaryotic promoters based on prediction of transcriptional units.

Identification of promoters is very important in understanding gene regulating relationships in an organism, and computational identification of promoters has been a long standing problem in computational biology. A new method was presented to predict promoter regions in prokaryotic organism. The method predicted transcription unit (TU) first and the TU was divided into singlet that contains only one single gene in a TU, and operon that contains more than one gene. Based on these predicted TUs, promoter was predicted for each TU using hidden Markov model including explicit state duration density. Both predicted TUs and promoters were satisfying.

Algorithms↗

PubMed1989

Prediction of outcome from critical illness. A comparison of clinical judgment with a prediction rule.

Quantitative methods to enhance clinical judgment would be of tremendous benefit to physicians caring for the critically ill. The ability of physicians to predict outcome is a logical standard on which to base the prospective evaluation of a prediction rule intended for this clinical use. The APACHE (acute physiology and chronic health evaluation)-II score was compared with critical care physicians' prediction of outcome for a group of patients in a medical intensive care unit. Physicians were significantly better in predicting outcome in the critically ill. However, the APACHE-II score was still a good predictor of outcome in the intensive care unit and, according to analysis using Bayes' theorem, might still be a useful test to support physicians' judgment, especially in patients with a predicted mortality risk of less than 30%.

Bayes Theorem↗

PubMed1984

Predictive tests for the response to cancer chemotherapy: limitations related to the prediction of rare events.

The reliability of a predictive test may be characterized by its sensitivity and specificity. The probability that a predicted event will actually occur depends on these indexes as well as the frequency of the predicted event. If such a test is used to predict for the therapeutic effect of single-agent chemotherapy in cancer patients, its predictive value is markedly affected by a generally low therapeutic efficacy in an unselected population.

Antineoplastic Agents↗

PubMedDate not supplied

Defining "disease" in epidemiologic studies of pulmonary function: percent of predicted or difference from predicted?

Epidemiologic studies often seek to determine the presence and magnitude of association between a trait and a disease, and spirometry test results are often used to define "disease". We evaluated two methods of comparing observed to predicted FEV1. The percent of predicted method is the ratio of a subject's observed to predicted result, and the residual method is the difference between the predicted and the observed result. FEV1 data from 541 men were used for computer simulated sampling for epidemiologic study of groups with different age structures. The residual method was superior because it produced more consistent measures of association, was less likely to produce an apparent association when one did not exist, and is more consistent with the statistical basis of the commonly employed prediction equations.

Adult↗

PubMed1993

Attitudes toward direct predictive testing for the Huntington disease gene. Relevance for other adult-onset disorders. The Canadian Collaborative Group on Predictive Testing for Huntington Disease.

OBJECTIVE: To assess attitudes toward, and projected utilization of, direct mutation testing by individuals at risk for Huntington disease (HD). DESIGN: Prior to the cloning of the gene for HD, a questionnaire concerning the use of a definitive test was constructed and mailed to 354 participants in the Canadian Collaborative Study for HD. Completed questionnaires were received from 250 participants (response rate, 71%). Persons were asked to indicate whether they would participate in a new predictive test that was either 100% accurate (the definitive test, requiring blood only from the proband) or only 99% accurate. RESULTS: Most (72%) of the persons who had previously received a result in a predictive testing program said they would request testing in either situation. Significantly more persons would request the definitive test than the 99% accurate test (72% vs 58%; P < .02). Respondents for whom testing was uninformative in the linkage test program or who had previously received an increased-risk result were more likely to indicate they would use the test than those who received a decreased-risk result or chose not to have the original test (P = .0003). Less than half (46%) of the participants who initially chose not to have the linkage test said they would return for the new direct test. The major factor that has limited acceptance of predictive testing for this group is the concern about receiving an increased-risk result in the absence of any therapy to alter progression of the disease. CONCLUSIONS: A direct mutation test for HD will most readily be accepted by persons who wanted but could not previously receive a result in the linkage test program and those who previously received an increased-risk result. In the absence of therapy, the majority of persons who previously chose not to have predictive testing are unlikely to participate in a new test despite improved accuracy. This has implications for the expected demands for testing services for other adult-onset genetic disorders.

Attitude to Health↗

PubMed2005

An integrative approach to CTL epitope prediction: a combined algorithm integrating MHC class I binding, TAP transport efficiency, and proteasomal cleavage predictions.

Reverse immunogenetic approaches attempt to optimize the selection of candidate epitopes, and thus minimize the experimental effort needed to identify new epitopes. When predicting cytotoxic T cell epitopes, the main focus has been on the highly specific MHC class I binding event. Methods have also been developed for predicting the antigen-processing steps preceding MHC class I binding, including proteasomal cleavage and transporter associated with antigen processing (TAP) transport efficiency. Here, we use a dataset obtained from the SYFPEITHI database to show that a method integrating predictions of MHC class I binding affinity, TAP transport efficiency, and C-terminal proteasomal cleavage outperforms any of the individual methods. Using an independent evaluation dataset of HIV epitopes from the Los Alamos database, the validity of the integrated method is confirmed. The performance of the integrated method is found to be significantly higher than that of the two publicly available prediction methods BIMAS and SYFPEITHI. To identify 85% of the epitopes in the HIV dataset, 9% and 10% of all possible nonamers in the HIV proteins must be tested when using the BIMAS and SYFPEITHI methods, respectively, for the selection of candidate epitopes. This number is reduced to 7% when using the integrated method. In practical terms, this means that the experimental effort needed to identify an epitope in a hypothetical protein with 85% probability is reduced by 20-30% when using the integrated method. The method is available at http://www.cbs.dtu.dk/services/NetCTL. Supplementary material is available at http://www.cbs.dtu.dk/suppl/immunology/CTL.php.

ATP-Binding Cassette Transporters↗

PubMed1988

Prediction and self-prediction of ovulation in clomiphene citrate-treated patients.

We studied 15 infertile patients for a total of 25 cycles in order to compare the predictive value of the following parameters in timing ovulation: basal body temperature (BBT), cervical mucus, serum E2 and LH, follicular growth as shown by ultrasonography, and urinary LH. The patients themselves tested urinary LH at home using Clearplan kits. BBT had low value as a predictive test for the time of ovulation, whereas ultrasonography had a predictive value of 9%, serum E2 50%, cervical mucus 59%, serum LH 63.6% and Clearplan kits 63.6%. The best predictive reliability in timing ovulation was obtained by considering both serum LH and E2 measurements. The Clearplan kits were as reliable as serum LH measurements and have greater practical advantages.

Adult↗

PubMed1996

A research to develop a predicting system of mammalian subacute toxicity. I. Prediction of subacute toxicity using the biological parameters of acute toxicities.

Predicting equations of subacute toxicity were developed by analyzing rat acute and subacute toxicity data of 56 chemicals of various structures. Minimum or 10% effect level in acute or subacute toxicity was estimated as a "biological parameter". Good regression equations were established between the geometrical means ("combined parameters") of any two of the parameters of acute and subacute toxicities and introduction of log P to the equations improved the correlations with a statistically significant multiple regression coefficient. The lowest predicted effect level of the subacute toxicity, which is selected from the data calculated by the above several correlations, can predict the upper limit of the no observed effect level. In recent years, for research and development of new chemical substances, it becomes one of the important factors that these have a lower environmental load in nature. Eventually, it becomes essential to evaluate not only their acute effects on human or environments, but also their chronic influences when they are to be exposed for a long period of time, and the cost for such verification is becoming a breaking factor for research and development. Thus, the development of a new technique which estimates the environmental load of a chemical substance including toxic effects on human with lower cost is now being attempted. For example, the development of in vitro new alternative methods using cultured cells, the utilization of a data base or software which relates mammalian and environmental toxicities and so on are internationally carried forwards. As for the latter, quantitative structure-activity relationship (QSAR) techniques have been applied practically to decide appropriate toxicity tests needed for regulatory purposes by EPA/TSCA, ITC/TSCA and FDA/FDAA in the USA. In addition, it was concluded recently in a joint meeting of EU and US-EPA that the approach by QSAR techniques was useful to specify the new chemical substances which are to be required toxicological examinations. In these QSAR techniques, however, while there are some considerations about common mechanisms of toxicity among chemicals with a similar structure (Congeneric chemicals, Congeners) for establishing of correlation formulas, for chemicals with various structures (Non-congeneric chemicals, Non-congeners) there often lack such common considerations. In addition, biological or physiological factors which are basic toxic indices are often ignored. In a previous study, we researched acute and subacute oral toxicities of industrial common chemicals in rats and reported the followings; 1) their subacute toxicological spectrum in target organs/tissues and morphologic changes was very limited and specific, 2) the important targets were liver, kidneys, blood (spleen) and stomach and these are considered the sites of dominant exposure due to the kinetics of chemical substances, 3) the morphological changes were hepatocellular hypertrophy, deposition of substance in renal tubules, extramedullary hematopoiesis in spleen and mucous lesion in stomach, and these are implying adaptation such as induction of drug-metabolizing enzymes, overload to renal function, anemia from erythrocyte destruction, and direct reaction, respectively, 4) there seems to occur a series of direct and adaptive reactions to exclude the "foreign compounds" which do not show any specific biological activities, 5) it is also considered that there is a possibility to establish a correlation between toxicological findings or target organs/tissues of both acute and subacute toxicities by their continuity. Therefore, in the present study, a predicting equation of subacute (28-day repeated dose) toxicity is attempted to develop from acute (single dose) toxicity data by considering both common mechanisms and biological factors for non-congeneric industrial chemical substances.

Animals↗

PubMed1995

Two novel T cell epitope prediction algorithms based on MHC-binding motifs; comparison of predicted and published epitopes from Mycobacterium tuberculosis and HIV protein sequences.

We have designed two computer-based algorithms for T cell epitope prediction, OptiMer and EpiMer, which incorporate current knowledge of MHC-binding motifs. OptiMer locates amphipathic segments of protein antigens with a high density of MHC-binding motifs. EpiMer identifies peptides with a high density of MHC-binding motifs alone. These algorithms exploit the striking tendency for MHC-binding motifs to cluster within short segments of each protein. Putative epitopes predicted by these algorithms contain motifs corresponding to many different MHC alleles, and may contain both class I and class II motifs, features thought to be ideal for the peptide components of synthetic subunit vaccines. In this study, we describe the use of OptiMer and EpiMer for the prediction of putative T cell epitopes from Mycobacterium tuberculosis and human immunodeficiency virus protein antigens, and demonstrate that these two algorithms may provide sensitive and efficient means for the prediction of promiscuous T cell epitopes that may be critical to the development of vaccines against these and other pathogens.

Algorithms↗

PubMed1994

Prediction of failure to survive following in-hospital cardiopulmonary resuscitation: comparison of two predictive instruments.

The purpose of this study is to compare two clinical predictive rules, the pre-arrest-morbidity (PAM) index and the prognosis-after-resuscitation (PAR) score, which predict failure to survive following in-hospital cardiopulmonary resuscitation (CPR). The study population consisted of 274 consecutive adult patients who underwent CPR at University College Hospital in Galway, Ireland over a 2-year period. The PAM and PAR scores were calculated from the most recent data available for each variable prior to cardiac arrest. Performance of the predictive scores was compared using Student's t-test, Pearson chi-square, Fisher's exact test, and receiver-operating characteristic (ROC) curves where appropriate. The PAM index identified 23 patients with a score > 4, while the PAR score identified 59 patients with a score > 5, none of whom survived. The sensitivity of the PAR score for the prediction of failure to survive was 23.7%, while that of the PAM index was 9.2%; neither index incorrectly identified a patient as a non-survivor who eventually survived. The PAR score also had a greater area under the ROC curve, although this difference was not statistically significant (P = 0.07). In summary, the PAR score performed better than the PAM index in the identification of patients who are unlikely to survive following CPR. Although further confirmation is necessary, it may provide useful prognostic information to physicians and patients involved with decisions about do-not-resuscitate orders.

Adolescent↗

PubMed2005

Predicting pressure ulcer risk: comparing the predictive validity of 4 scales.

OBJECTIVE: To compare the predictive validity of 4 pressure ulcer risk assessment tools. METHODS: Prospective clinical design in which 230 subjects free of pressure ulceration on admission were assessed using the Braden, Gosnell, Norton, and Waterlow scales within 48 hours of admission. Subjects' skin condition was assessed once every 24 hours for a minimum of 14 days to identify any skin breakdown. RESULTS: Based on Youden's index, the Gosnell Scale had better predictive validity in identifying patients at risk for pressure ulcer development (J = 68%). The other scales did not predict individuals at risk with high accuracy, despite having high sensitivity and specificity. CONCLUSION: Numerous pressure ulcer risk assessment tools have been developed, but sufficient evidence for using one tool over another does not exist. In this study, the Gosnell Scale was found to be more appropriate for application in patients with neurologic and orthopedic conditions. CLINICAL RELEVANCE: Being able to predict which patients are at risk for pressure ulcers can assist practitioners in tailoring care to prevent unnecessary complications and suffering, as well as reduce costs.

Adult↗

PubMed2006

Hyaluronic acid levels can predict severe fibrosis and platelet counts can predict cirrhosis in patients with nonalcoholic fatty liver disease.

BACKGROUND AND AIM: Nonalcoholic fatty liver disease (NAFLD) represents a spectrum of liver disease from simple steatosis to cirrhosis. Therefore, markers for predicting NAFLD with advanced fibrosis are needed. The aim of this study was to establish non-invasive predictive markers of liver fibrosis in NAFLD. METHODS: One hundred and forty-eight patients were diagnosed as having biopsy-proven NAFLD. In order to separately identify severe fibrosis (bridging fibrosis plus cirrhosis) and cirrhosis, the patients were analyzed twice: first, as mild fibrosis versus severe fibrosis; and second, as non-cirrhosis versus cirrhosis. Univariate and multivariate analyses were conducted. The diagnostic ability to detect severe fibrosis and cirrhosis was assessed by the area under the receiver operating characteristic curve. The cut-off values of serum markers to detect severe fibrosis and cirrhosis were determined. RESULTS: Hyaluronic acid was selected as a predictive marker for severe fibrosis. A cut-off value of 42 ng/mL of hyaluronic acid had a 100% predictive value for patients free of severe fibrosis and was associated with an optimal combination of sensitivity (100%, 95% confidence interval [CI] 90-100%) and specificity (89%, 95%CI 80-94%). The platelet count was found to be an independent predictor of cirrhosis. A cut-off value of 16 x 10(4)/microL for the platelet count was associated with an optimal combination of sensitivity (100%, 95%CI 82-100%) and specificity (95%, 95%CI 90-98%). CONCLUSIONS: Hyaluronic acid levels can accurately identify NAFLD patients with severe fibrosis, and the platelet count can identify NAFLD patients with cirrhosis. Thus, these markers offer a good guideline for the assessment of hepatic fibrosis in the many patients with NAFLD.

Adolescent↗

PubMed2003

Early change in patient-reported health during lung cancer chemotherapy predicts clinical outcomes beyond those predicted by baseline report: results from Eastern Cooperative Oncology Group Study 5592.

PURPOSE: To determine the ability of longitudinal patient-reported health (PRH) scores to enhance prediction of clinical outcomes beyond baseline scores. PATIENTS AND METHODS: In 573 advanced non-small-cell lung cancer patients enrolled in a phase III clinical trial, we used baseline and 6-week follow-up PRH scores to predict best response to treatment, disease progression, and survival. Using regression analyses, we tested the predictive ability of the five subscales of the Functional Assessment of Cancer Therapy-Lung (physical, functional, social/family, emotional well-being, and the lung cancer subscale) as well as the trial outcome index (TOI) aggregate score. RESULTS: After clinical factors were controlled for, baseline physical well-being (PWB) and TOI scores predicted all three clinical outcomes. A higher baseline PWB score was associated with a better response to treatment (odds ratio, 1.09; P <.001) and lower risk of death (risk ratio, 0.95; P <.001). Higher baseline TOI score was associated with a lower risk of disease progression (risk ratio, 0.98; P <.001). These two baseline predictors (PWB and TOI) were then used along with 6-week change scores to classify patients into four groups: low baseline-declined, low baseline-improved, high baseline-declined, and high baseline-improved. Patients with low baseline-declined PWB scores showed the worst responses to treatment and survived the shortest duration. Patients with low baseline-declined TOI scores had the shortest time to progression. CONCLUSION: The physical aspects of baseline PRH and PRH change during chemotherapy are significant predictors of clinical outcomes in lung cancer. This has implications for patient stratification in clinical trials and may aid decision-making in clinical practice.

Adult↗

PubMed2005

The predictive value of the height ratio and thyromental distance: four predictive tests for difficult laryngoscopy.

Preoperative evaluation of anatomical landmarks and clinical factors help identify potentially difficult laryngoscopies; however, predictive reliability is unclear. Because the ratio of height to thyromental distance (RHTMD) has a demonstrably better predictive value than the thyromental distance (TMD), we evaluated the predictive value and odds ratios of RHTMD versus mouth opening, TMD, neck movement, and oropharyngeal view (modified Mallampati). We collected data on 550 consecutive patients scheduled for elective-surgery general anesthesia requiring endotracheal intubation and then assessed all five factors before surgery. An experienced anesthesiologist, not apprised of the recorded preoperative airway assessment, performed the laryngoscopy and grading (as per Cormack and Lehane's classification). Difficult laryngoscopy (Grade 3 or 4) occurred in 69 patients (12.5%). RHTMD had a higher sensitivity, positive predictive value, and fewer false negatives than the other variables tested. In the multivariate analysis, three criteria were found independent for difficult laryngoscopy (neck movement < or =80 degrees; Mallampati Class 3 or 4, and RHTMD > or =23.5). The odds ratio (95% confidence interval) of the RHTMD, Mallampati class, and neck movement were 6.72 (3.29-13.72), 2.96 (1.63-5.35), and 2.73 (1.14-6.51), respectively. The odds ratio for RHTMD was the largest and thus may prove a useful screening test for difficult laryngoscopy.

Adult↗

PubMedDate not supplied

[Positive predictive value and negative predictive value of spiral CT in the diagnosis of closed loop obstruction complicated by intestinal ischemia].

PURPOSE: To assess the positive predictive value and the negative predictive value of spiral CT in the diagnosis of "closed-loop" obstruction complicated by intestinal ischaemia. MATERIALS AND METHODS: Between January 1999 and January 2002, 120 patients with small intestine closed-loop obstruction who had undergone surgical laparotomy within 2-6 hours from abdominal and pelvic spiral CT were retrospectively reviewed. The CT scans were performed using 5-mm slice thickness, 1 s scan delay, 5 x 5-mm collimation and 1.5 pitch after administering i.v. iodinated contrast material (120 ml volume, 60 s scan delay, 2.5-3 ml/s rate) with an automatic injector. For the diagnosis of closed-loop obstruction the following CT findings were examined: identification of the transitional area, 'C', 'U' or 'beak' shape of the obstructed loops, radial distribution of the involved mesenteric vessels. For the diagnosis of loop ischaemia, the following findings were evaluated in addition to the CT signs described above: submucosal oedema, increased, reduced, or no enhancement of the loop walls, oedema of the mesenteric vessels, fluid within the loops or in the intraperitoneal spaces. RESULTS: 'U', 'C', 'beak' loop configuration with poor or no contrast enhancement of the obstructed loop walls, ascites, rotation and engorgement of mesenteric vessels enabled the diagnosis of 26 cases of closed-loop obstruction complicated by ischaemia, infarction. U- or C-shaped loops with radial distribution and/or rotation of mesenteric vessels towards the obstruction site suggested the correct diagnosis in 94 cases, but did not allow identification of ischaemia in 25 cases. The positive predictive value of spiral CT related to ischaemic loop complications was 100%; the negative predictive value was 73%. CONCLUSIONS: Spiral CT is a reliable imaging technique enabling the diagnosis of closed-loop obstruction with or without intestinal ischaemic complications. Any alterations detected in the trophic status of the loops or mesentery imply ischaemic complications requiring emergency surgery. On the contrary, if only CT signs of closed-loop obstruction are detected, the existence and/or development of ischaemia cannot be ruled out.

Adult↗

PubMed1999

Analysis and assessment of ab initio three-dimensional prediction, secondary structure, and contacts prediction.

CASP3 saw a substantial increase in the volume of ab initio 3D prediction data, with 507 datasets for fifteen selected targets and sixty-one groups participating. As with CASP2, methods ranged from computationally intensive strategies that attempt to recreate the physical and chemical forces involved in protein folding to the more recent knowledge-based approaches. These exploit information from the structure databases, extracting potentially similar fragments and/or distance constraints derived from multiple sequence alignments. The knowledge-based approaches generally gave more consistently successful predictions across the range of targets, particularly that of the Baker group (Bystroff and Baker, J Mol Biol 1998;281:565-577; Simons et al. Proteins Suppl 1999;3:171-176), which used a fragment library. In the secondary structure prediction category, the most successful approaches built on the concepts used in PHD (Rost et al. Comput Appl Biosci 1994;10:53-60), an accepted standard in this field. Like PHD, they exploit neural networks but have different strategies for incorporating multiple sequence data or position-dependent weight matrices for training the networks. Analysis of the contact data, for which only six groups participated, suggested that as yet this data provides a rather weak signal. However, in combination with other types of prediction data it can sometimes be a useful constraint for identifying the correct structure.

Animals↗