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At least 1,207 records · Page 67Linked to original sources
PubMed2003

A transient tobacco expression system coupled to MALDI-TOF-MS allows validation of the impact of differential targeting on structure and activity of a recombinant therapeutic glycoprotein produced in plants.

Tobacco-based transient expression was employed to elucidate the impact of differential targeting to subcellular compartments on activity and quality of gastric lipase as a model for the production of recombinant glycoproteins in plants. Overall N-linked glycan structures of recombinant lipase were analyzed and for the first time sugar structures of its four individual N-glycosylation sites were determined in situ by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) on a trypsin digest without isolation or deglycosylation of the peptides. Three glycosylation sites contain both complex-type N-glycans and high-mannose-type structures, the fourth is exclusively linked to high-mannose glycans. Although the overall pattern of glycan structures is influenced by the targeting, our results show that the type of glycans found linked to a given Asn residue is largely influenced by the physico-chemical environment of the site. The transient tobacco system combined with MALDI-TOF-MS appears to be a useful tool for the evaluation of glycoprotein production in plants.

Animals↗
PubMed2004

A factor analysis of the Strauss and Carpenter revised outcome criteria scale: a validation of the French translation.

This article seeks to validate the French translation of the Strauss and Carpenter revised outcome criteria scale (SCOCS-R) through the study of its interrater reliability, its convergent validity, and its factor structure. Using a sample of 113 DSM-IV schizophrenic subjects, we assessed the interrater reliability of the SCOCS-R and its convergent validity with an already validated scale (Social and Occupational Functioning Assessment Scale). The factor structure of the SCOCS-R was assessed using a principal components analysis. Interrater reliability was excellent (ri > or = 0.88 for each of the individual items), and the convergent validity with the Social and Occupational Functioning Assessment Scale proved to be highly satisfactory (r = 0.89; p < .0001). Factor analyses yielded two factors corresponding to social functioning and professional functioning. These factors accounted for 78% of the variance of outcome. These results demonstrate the reliability and the validity of the French translation of the SCOCS-R. Moreover, the two dimensions yielded by our factor analysis add to the evidence of the multidimensional structure of outcome. This article supports the relevance of the SCOCS-R to assess the dimensions of outcome in schizophrenic subjects.

Diagnostic and Statistical Manual of Mental Disord↗
PubMed2002

Factor structure of the Multnomah Community Ability Scale.

More and more, Intensive Community Treatment programs in Canada use questionnaires to evaluate the health and social functioning of individuals suffering from a severe mental illness. However, seldom are these tools subject to psychometric analyses to establish their validity on independent samples. This article presents the results of the validation of the French version of the Multnomah Community Ability Scale. Confirmatory factor analyses were carried out to assess the factorial structure. The factor structure, four dimensions with three items, emerging from a first sample was replicated with data from a different sample of clients. Moreover, these four dimensions respect the initial factor solution of the Multnomah Community Ability Scale, which are a) interference with functioning, b) adjustment to living, c) social competence, and d) behavior problems. The study shows the structural validity of this brief questionnaire, which could be useful both for clinical and research settings to evaluate the effectiveness of interventions.

Activities of Daily Living↗
PubMed2004

Validation of the aphasic depression rating scale.

BACKGROUND AND PURPOSE: The Aphasic Depression Rating Scale (ADRS) was developed to detect and measure depression in aphasic patients during the subacute stage of stroke. METHODS: Six experts selected an initial sampling of behavioral items from existing depression rating scales. Stroke patients (aphasic and nonaphasic) were assessed with these items by the rehabilitation staff, with the Hamilton Depression Rating Scale (HDRS) for nonaphasic patients only, by a psychiatrist, and by the rehabilitation staff with Visual Analog Scales (VAS). A second item selection was conducted after a regression algorithm was run including VAS as independent variables (criterion validity) and after their factorial structure was analyzed with a principal component analysis (factorial validity). The construct validity was evaluated with respect to the other depression assessments. A threshold for the diagnosis of depression was computed with respect to the psychiatrist's diagnosis. Interrater and test-retest reliability were assessed in 2 additional groups of aphasic patients. RESULTS: Eighty patients participated in the study (59 aphasic). Fifteen behavioral items from existing depression rating scales were selected, and 9 were retained after the validation process. ADRS correlated highly with VAS and HDRS (r=0.60 to 0.78, P=10(-4) to 10(-6)). With respect to the psychiatrist's diagnosis, the sensitivity and specificity of ADRS were 0.83 and 0.71, respectively, when the threshold was set at 9/32. Its factorial structure was comparable to HDRS structure. Interrater and test-retest reliability were high (average kappa coefficient of the 9 items=0.69). CONCLUSIONS: ADRS is a valid, reliable, sensitive, and specific tool for the evaluation of depression in aphasic patients during the stroke subacute phase.

Adult↗
PubMed2005

Adaptation of panic-related psychopathology measures to Russian.

The study reports results of adaptation of panic-related psychopathology measures to Russian, including the Anxiety Sensitivity Index (ASI), the Agoraphobic Cognitions Questionnaire (ACQ), and the Mobility Inventory for Agoraphobia (MIA). Psychometric properties (e.g., reliability, factor structure, endorsement) and external validity of the adaptations were evaluated in a representative sample of Moscow residents (N = 390) and Ukrainian undergraduates (N = 492). The adapted ASI was generally equivalent to the original English-language version. The ACQ showed structural equivalency but did not exhibit expected specificity to panic. Finally, the MIA displayed notable structural discrepancies but had external validity comparable to the original.

Adult↗
PubMed2001

Factor analysis of an outcome interview for use in clinical trials of traumatically brain-injured patients: a preliminary study.

OBJECTIVE: To study the factor structure, internal consistency, concurrent validity, and sensitivity to detect change in patient report of problems of a structured interview in relationship with accepted outcome measures. DESIGN: Outcome status of patients with severe traumatic brain injury participating in a randomized, phase III, multicenter clinical trial was assessed at 6 mo postinjury using the Glasgow Outcome Scale, the Disability Rating Scale, and the Severe Traumatic Brain Injury Outcome Interview. RESULTS: Exploratory factor analysis of the Severe Traumatic Brain Injury Outcome Interview produced a meaningful five-factor model: (1) activities of daily living; (2) cognitive; (3) affective; (4) behavioral; and (5) instrumental activities of daily living. The internal consistency of the factors ranged from moderate (0.61 instrumental activities of daily living) to high (0.94 activities of daily living); the interfactor correlations were moderate. The summed factor scores were significantly correlated with measures of global outcome: the Glasgow Outcome Scale (r = 0.66; P < 0.0001) and the Disability Rating Scale (r = 0.61; P < 0.0001). Patient report of cognitive problems correlated moderately with the neuropsychological tests. The summed factor scores were sensitive to change over time. CONCLUSIONS: Overall, the interview assessed the major important features of outcome pertinent to traumatic brain injury and demonstrated greater sensitivity to subtle changes over time than the unidimensional approaches, such as the Glasgow Outcome Scale and Disability Rating Scale.

Activities of Daily Living↗
PubMed2005

Using a library of structural templates to recognise catalytic sites and explore their evolution in homologous families.

Catalytic site structure is normally highly conserved between distantly related enzymes. As a consequence, templates representing catalytic sites have the potential to succeed at function prediction in cases where methods based on sequence or overall structure fail. There are many methods for searching protein structures for matches to structural templates, but few validated template libraries to use with these methods. We present a library of structural templates representing catalytic sites, based on information from the scientific literature. Furthermore, we analyse homologous template families to discover the diversity within families and the utility of templates for active site recognition. Templates representing the catalytic sites of homologous proteins mostly differ by less than 1A root mean square deviation, even when the sequence similarity between the two proteins is low. Within these sets of homologues there is usually no discernible relationship between catalytic site structure similarity and sequence similarity. Because of this structural conservation of catalytic sites, the templates can discriminate between matches to related proteins and random matches with over 85% sensitivity and predictive accuracy. Templates based on protein backbone positions are more discriminating than those based on side-chain atoms. These analyses show encouraging prospects for prediction of functional sites in structural genomics structures of unknown function, and will be of use in analyses of convergent evolution and exploring relationships between active site geometry and chemistry. The template library can be queried via a web server at and is available for download.

Algorithms↗
PubMed1999

Postoperative pain expression in preschool children: validation of the child facial coding system.

OBJECTIVE: The purposes of the study were threefold: (a) to determine whether a measurement system based on facial expression would be useful in the assessment of post-operative pain in young children; (b) to examine construct validity in terms of structure, consistency, and dynamics of the facial display; and (c) to evaluate concurrent validity in terms of associations with global judgments of the children's pain. PATIENTS: One hundred children between the ages of 13 and 74 months were video-taped for a maximum of 1 hour after arrival in the postanesthesia care unit (PACU) at British Columbia's Children's Hospital. OUTCOME MEASURES: Videotapes were edited into 20-second blocks, randomly selected from each 2-minute time period taped during the hour following surgery, and coded for the presence or absence of 13 facial actions in the Child Facial Coding System (CFCS). RESULTS: Facial expressions were characterized primarily by the following constellation of actions: open lips, lowered brows, a deepened nasolabial furrow, mouth stretched wide in both horizontal and vertical directions, eyes squeezed shut or squinted, and raised cheeks. A principal components analysis indicated that these actions comprised a single factor, accounting for 55% of the variance in CFCS actions. Facial action summary scores were correlated with a visual analog rating of global pain, confirming that the CFCS has convergent validity. Facial action summary scores, i.e., pain displays, were at their lowest immediately after admittance to the PACU and just before the child's release from the PACU. CONCLUSIONS: The present study demonstrated that the CFCS serves as a valid measurement tool for persistent pain in children.

Child↗
PubMed2000

Calculation of acoustic radiation using equivalent-sphere methods

Among the methods generally used to solve a problem in the domain of acoustic radiation, the equivalent sources method offers an interesting alternative. It consists in replacing the vibrating surface with a distribution of acoustic sources placed inside the structure. The contribution of each source is determined in such a way that the acoustic field radiated by these sources verifies the same boundary conditions on the structure. The number of unknowns in the problem is no longer directly linked to the number of mesh points on the structure, as with boundary elements methods, but to the number of equivalent sources employed in the model. The equivalent source method is therefore of major interest if the acoustic radiation of the structure can be approximated with a sufficiently low number of sources. This paper proposes its application when the equivalent source is a sphere. In this case, the number of unknowns is equal to the number of modes. In contrast to the one-point multipole, the sphere has a surface surrounding a closed volume to express the boundary conditions. Although sphere/multipole equivalence has been demonstrated, the surface of the sphere allows normalization of the functions used, leading to stabilization of the system to be resolved. First, the main acoustic radiation characteristics of a sphere and of the linear system verified by the modal coefficients of an equivalent sphere are presented. The different parameters of the model are then studied: position and radius of the equivalent sphere, truncation of the series, and influence of the spatial sampling (mesh). In the same vein, a second approach is presented. It consists of making each point of the structure correspond to a point of the sphere, and the vibrating field at the surface of the sphere is deduced from that of the structure by simple geometric projection. Results can be obtained very quickly as no matrix inversion is required. The accuracy of the results depends on the distance between the sphere and the structure. Finally, an experimental validation that uses both methods is presented and shows interesting results when the structure is closed, and when its shape is not too far removed from a sphere.

Journal Article↗
PubMed2005

Reliability and Validity Evaluation of the Psychopathy Checklist: Screening Version (PCL:SV) in Swedish correctional and forensic psychiatric samples.

This study evaluated the structural reliability, construct-related validity, and cultural validity generalization of the Hare Psychopathy Checklist: Screening Version (PCL:SV) in a sample of more than 560 male and female Swedish forensic psychiatric treatment patients, forensic evaluation patients, and criminal offenders. Structural reliability was excellent for most indices. PCL:SV scores were higher for males than females for total and Part 1 scores (interpersonal/affective features) but not for Part 2 (behavioral features). With some exceptions, PCL:SV scores were meaningfully related to aggression to others, a measure of risk for violence, substance use problems, personality disorder (positive), and psychosis (negative). Correlations between PCL:SV and aggression were larger for females than males, although the difference was smaller when personality disorder was held constant. The structural reliability and pattern of validity coefficients were comparable in these Swedish samples to other non-North American samples. Implications for the cross-cultural manifestation and correlates of psychopathy are discussed.

Adolescent↗
PubMed2005

Mania in the Swedish Twin Registry: criterion validity and prevalence.

BACKGROUND: In population surveys, the assessment of mania is commonly done by trained lay interviewers using structured diagnostic instruments: the validity of this approach has been questioned. We examined the criterion validity and prevalence of lifetime mania in a survey of Swedish twins conducted with interview methodology usually applied in psychiatric epidemiology. METHODS: 41 838 individuals in the Swedish Twin Registry were evaluated via a telephone interview that included the eight DSM-IV mania items, and these data were merged with inpatient hospitalization discharge diagnoses from two comprehensive national registries (the criterion). An algorithm with eight cut-points was used to diagnose lifetime mania, and compared by a receiver operator characteristic curve to the criterion. The algorithm requiring at least four positive items resembling a DSM-IV diagnosis. RESULTS: History of hospitalization for a psychiatric condition that included a manic episode was present for 0.7% of all living twins, and predicted non-response to the survey (OR = 0.5; 95% CI = 0.4-0.6). The incidence rate for first hospitalization was 2.1/10 000 year(-1). For > or =1 symptom (first cut-point), the prevalence, sensitivity and specificity were 3.6%, 39.0% and 96.6%; for > or = 4 symptoms (DSM-IV-like cut-point) 2.6%, 36.5% and 97.6%; and for eight symptoms 0.3%, 18.0% and 99.8%. Positive predictive values were, respectively, 5.5%, 7.0% and 29.8%. CONCLUSIONS: The performance of the telephone screening for mania by lay interviewers in terms of positive predictive power was not satisfactory; despite a high specificity, the false positive rate was high. The low population prevalence of mania, non-response bias, criterion choice and inherent limitations of the interviewing method are among the explanations. Assessment of a lifetime manic episode based on lay interviewer screening may yield misleading data.

Bipolar Disorder↗
PubMed2004

Traditional detection versus computer-controlled multilevel analysis of nuclear structures from donated human embryos.

BACKGROUND: Multinuclearity is known to correlate with decreased implantation and pregnancy rates. Thus, a valid detection of nuclear structures especially among otherwise good quality embryos may be of great importance in order to improve clinical outcome. In this study, we have compared traditional manual microscopic analysis with computer-controlled multilevel morphological assessment for analysis of nuclear status in human embryos. METHODS: In total, 84 donated 2- and 4-cell embryos with < or = 20% fragmentation from patients referred for IVF or ICSI treatment were included. Mono- and multinuclearity was recorded using traditional analysis as well as computer-controlled multilevel analysis of each intact embryo. Subsequently, the embryos were separated into individual blastomeres to assess the number of nuclear structures. All nuclear structures were fixed and stained for DNA. RESULTS: There was no significant difference (P = 1.0) between embryonic nuclear status detected by computer-controlled analysis of the intact embryos and of the separated blastomeres. Additionally, 100% of the fixed nuclear structures contained DNA. However, using traditional morphological analysis, significantly more embryos (26%) had incorrect nuclear status detected (P = 0.002). Further, the presence of <10% embryonic fragmentation had no impact on the correct detection of nuclear structures using the multilevel analysis. For embryos with 11-20% fragmentation, 86% of the nuclear structures detected in the separated blastomeres were found in the intact embryos. The mean diameter of nuclear structures was significantly decreased from 22.1 microm in mononucleate 2-cell embryos to 18.7 microm in mononucleate 4-cell embryos (P < 0.001). CONCLUSION: The results of this study indicate that the use of computer-controlled multilevel morphological analysis can improve the detection of nuclear structures in human embryos.

Adult↗
PubMed2006

Risk factors for specific upper limb disorders as compared with non-specific upper limb pain: assessing the utility of a structured examination schedule.

BACKGROUND: Few community-based epidemiological investigations of upper limb disorders (ULDs) have classified cases by validated procedures involving a structured clinical examination. AIM: To compare risk factor profiles for different diagnostic categories of ULD using one such examination scheme. METHODS: A questionnaire about upper limb pain and demographic, occupational and psychosocial risk factors was mailed to 10,264 adults from two English general practices, followed by standardized physical examination in those with arm or neck pain. Logistic regression was used to compare those with specific ULDs and non-specific arm pain with those who had no neck or arm symptoms. RESULTS: There was a 59% response rate. A total of 1,197 subjects with arm or neck pain underwent standardized physical examination and were classified as having one or more of 11 specific ULDs or non-specific regional pain. Among these, 250 subjects with specific ULDs and 176 with only non-specific arm pain were compared with 2,248 subjects who had no neck or arm symptoms. Certain physical risk factors were more strongly associated with specific disorders than with non-specific pain. In comparison with pain-free subjects, the odds ratios (ORs) in keyboard users (>or=1 h versus <1 h/day) were 3.1 (95% CI 1.3, 7.8) for hand-wrist tendonitis but 1.3 (0.8, 2.1) for non-specific hand-wrist pain. Other differential associations were found with age, sex, manual versus non-manual employment and smoking. Unexpectedly, low vitality was similarly associated with both specific disorders and non-specific pain. CONCLUSION: These findings suggest that the schedule may usefully distinguish disorders that differ in their association with physical risk factors.

Adult↗
PubMed2001

Structure of a persistent heptachlorobornane in toxaphene (b7-1000) agrees with molecular model predictions.

A Cl(7) component of technical toxaphene (CTT), previously detected in marine mammals and fish and referred to as "7-1", was isolated from contaminated estuarine sediment using preparative solid-liquid chromatography followed by reversed-phase HPLC. The structure of this compound, elucidated by GC/MS and (1)H NMR, was 2-endo,3-exo,5-endo,6-exo,8,8,10-heptachlorobornane (hereafter referred to as B7-1000). This newly identified CTT eluted in the nonpolar fraction from silica and shares the alternating endo-exo chlorine substitution pattern with other relatively nonpolar, persistent congeners (e.g., B8-1413 and B9-1679). Based on ECNI-MS response, levels of B7-1000 in tissue samples of various higher organisms including humans were as high as 16% of B8-1413. Enantioselective determination of B7-1000 using a modified cyclodextrin chiral stationary phase (beta-BSCD) resulted in enantiomer ratios that were depleted in adipose tissue of a marine bird (skua) and Weddell seal blubber (0.3 and 0.5, respectively), but not in elephant seal blubber (1.1). Elucidation of the structure of B7-1000 thus validates previous predictions of persistence based on structure-activity relationships, chromatographic properties, and molecular modeling.

Animals↗
PubMed2006

Validation of surgical site infection surveillance in the Netherlands.

OBJECTIVES: To describe how continuous validation of data on surgical site infection (SSI) is being performed in the Dutch National Nosocomial Infection Surveillance System (Preventie Ziekenhuisinfecties door Surveillance [PREZIES]), to assess the quality and accuracy of the PREZIES data, and to present the corresponding outcomes of the assessment. DESIGN: Mandatory, 1-day on-site validation visit to participating hospitals every 3 years. The process of surveillance, including the quality of the method of data collection, is validated by means of a structured interview. The use of SSI criteria is validated by review of medical records, with the judgment of the validation team as the criterion standard. SETTING: Hospitals participating in PREZIES. RESULTS: During 1999-2004, the validation team visited 40 hospitals and reviewed 859 medical charts. There was no deviation between reports of SSI by infection control professionals and findings by the PREZIES validation team at 30 hospitals and 1 deviation in each of 10 hospitals; the positive predictive value was 0.97, and the negative predictive value was 0.99. The validation team often gave advice to the hospital, aimed at perfecting the process of surveillance. On 2 occasions, data were removed from the PREZIES database after the validation visit revealed deviations from the SSI surveillance protocol that could have resulted in nonrepresentative SSI rate data. CONCLUSIONS: PREZIES is confident that the assembled Dutch SSI surveillance data are reliable and robust and are sufficiently accurate to be used as a reference for interhospital comparison. PREZIES will continue performing on-site validation visits, to improve the process of surveillance and ensure the reliability of the surveillance data.

Cross Infection↗
PubMed1994

Medical data and knowledge management by integrated medical workstations: summary and recommendations.

The health care professional workstation will function as an interface between the user and the patient data as well as an interface pertinent medical knowledge. Appropriate knowledge focus will require the workstation to recognize the concepts and structure of patient data, and understand the scope and access methods of knowledge sources. Issues are organized around five major themes: (i) structure, (ii) reliability and validation, (iii) views, (iv) location, and (v) ethical and legal. Conventional database representations can effectively address data structure and format variations that will inevitably persist in local data stores. The reliability of data and the validation of knowledge are critical issues that may determine the ultimate utility of clinical workstations. Alternative views of patient information and knowledge sources represent the true power of an intelligent data portal, represented by a well-designed clinical workstation. Both data and knowledge are optimally represented in decentralized information networks, although the confidentiality and ownership of this information must be respected. Evolutionary progress toward consistent representations of knowledge and patient data will be facilitated by the establishment of self-documentation standards for the developers of data encoding systems and knowledge sources, perhaps extended from the preliminary model afforded by the Unified Medical Language System (UMLS).

Computer Security↗
PubMed2002

Redefining the factor structure of the Wechsler Memory Scale-III: confirmatory factor analysis with cross-validation.

The purpose of this study was to revisit the underlying factor structure of the Wechsler Memory Scale-III. The WMS-III Technical Manual (Wechsler, 1997) presented findings from confirmatory factor analyses that support a three- and five-factor solution with separate immediate and delayed memory factors. A rigorous structural equation modeling approach was used to examine the factor structure of the test. The results verify that a three-factor model composed of verbal (immediate and delayed), visual (immediate and delayed), and working memory factors accurately represents the factor structure of the WMS-III. Results were cross-validated on an independent sample.

Adolescent↗
PubMed2005

Describing partially unfolded states of proteins from sparse NMR data.

Proteins involved in signal transduction can usually be present in two states: an inactive and an active (signaling) state. In the case of photoreceptors such as PYP, it has been shown that the signaling state has a large degree of structural and dynamic disorder. Conventional structural NMR approaches present difficulties in describing such partially unfolded states. Owing to the disordered dynamical and transient nature of such states classical NOE-based information, when present, is sparse. Chemical shift changes upon partial unfolding can, however, be easily monitored from HSQC spectra. We show here that such states can be modeled by defining native-like inter-residue contacts for those residues that do not shift significantly upon partial unfolding. The feasibility of this approach is demonstrated using lysozyme as a test case and applied to model the partially unfolded signaling state (pB) of a truncated form of the photoactive yellow protein for which a "classical" NOE-based structure is available for validation. This approach should be generally applicable to systems in which part of the structure remains in a well-defined native-like conformation.

Bacterial Proteins↗