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PubMed2003

Conformation of alpha zeins in solid state by Fourier transform IR.

The major maize storage proteins (alpha zeins) are deposited as an insoluble mass in the protein bodies of the endosperm. Because they are insoluble in water, most structural studies are performed in alcohol solutions. To solve the question raised by several authors about denaturation of the alpha zein structure by alcohol, we analyze the secondary structure of alpha zeins prepared with and without solubilization in alcohol (corn gluten meal and protein bodies with high concentrations of alpha zeins and traces of beta zeins). The secondary structures of alpha zeins are analyzed in the solid state by Fourier transform IR spectroscopy (FTIR) in KBr pellets and solid-state 13C-NMR spectroscopy. The proportion of secondary structures obtained by FTIR of alpha zeins prepared with and without solubilization in alcohol yield almost identical proportions of alpha helices and beta sheets. The proportion of alpha helices (43%) agrees with that measured by circular dichroism in an alcohol solution. However, the proportion of beta sheets (28%) is higher than the one measured by the same technique. Gluten and protein body samples with high beta zein content showed higher beta sheet and lower alpha helix proportions than that obtained for alpha zein preparations. The solid-state 13C-NMR spectra show the carbonyl peak for the alpha zeins at delta 176 and for the sample rich in beta zeins at delta 172, which demonstrates the presence of a high content of alpha helices and beta sheets, respectively. These results indicate that alcohol solubilization does not affect the conformation of alpha zeins, validating the secondary structure measurements in solution.

Magnetic Resonance Spectroscopy↗
PubMed1995

The politics of nursing: a case study--clinical grading.

This paper is a study of the clinical grading policy for nurses in the United Kingdom and the extent to which the participating groups in the policy development process realized their objectives. The study is based on the literature available at the time of the research and the results of structured interviews with a range of individuals involved in the policy process. The results expose the cleavages between the different representative groups on the staff side. They also shed light on the differing power bases of the groups involved. In particular, they expose the weakness of nursing as a professional pressure group and the strength of the state and its agents in determining the outcomes of policy in the public arena. It is suggested that this weakness vis-à-vis the state is responsible for the failure of nurses to achieve a reward system which recognizes the value of clinical nursing expertise, and that the 'clinical grading' system, in practice, is having the opposite effect. The policy is explored from its origins, its acceptance on to the political agenda, its negotiation and agreement, its contentious implementation, the final outcomes, and its failure to establish a valid 'clinical' pay structure.

Clinical Competence↗
PubMed1995

Reliability, validity and factorial dimensions of the Interactive Observation Scale for Psychiatric Inpatients.

The Interactive Observation Scale for Psychiatric Inpatients (IOSPI) is characterized by the necessity of interaction between the rater and the patient during the evaluation process. The reliability, validity and factor structure of the IOSPI were evaluated by using a total of 186 sets of ratings accomplished by 2 nursing aides on 34 adult psychiatric inpatients submitted to weekly evaluations during the 3 first weeks of hospitalization. The patients were observed by the 2 nursing aides simultaneously during the morning shift (5 h). In the afternoon of the same day, they were interviewed by two psychiatrists who filled in separately the Brief Psychiatric Rating Scale (BPRS). Factor analysis of the 16 IOSPI items revealed 5 distinct clusters of items, which represented higher-order constructs of social interest, psychomotor agitation, psychoticism, neatness and irritability. It was found that the IOSPI has significant interrater reliability, estimated by an intraclass correlation coefficient of total score and factor score. The total scores of the IOSPI showed a significant correlation with the total scores of the BPRS, meeting the criteria of concurrent validity. The criteria of predictive validity were also met, since the patients who could be discharged presented IOSPI scores significantly lower than the patients who could not be discharged. In conclusion, the IOSPI met the requirements of an evaluation scale and can stimulate therapeutic attitudes of the nursing staff by its characteristics of interactive observation.

Factor Analysis, Statistical↗
PubMed2003

Spectroscopic and computational studies of Co3+-corrinoids: spectral and electronic properties of the B12 cofactors and biologically relevant precursors.

The B(12) cofactors methylcobalamin (MeCbl) and 5'-deoxyadenosylcobalamin (AdoCbl) have long fascinated chemists because of their complex structures and unusual reactivities in biological systems; however, their electronic absorption (Abs) spectra have remained largely unassigned. In this study, we have used Abs, circular dichroism (CD), magnetic CD (MCD), and resonance Raman spectroscopic techniques to probe the electronic excited states of Co(3+)Cbl species that differ with respect to their upper axial ligand, including MeCbl, AdoCbl, aquacobalamin (H(2)OCbl(+)), and vitamin B(12) (cyanocobalamin, CNCbl). Also included to probe the effect of the lower axial ligand on the electronic properties of Cbls is Ado-cobinamide (AdoCbi(+)), an AdoCbl derivative that lacks the tethered base 5,6-dimethylbenzimidazole (DMB) and instead binds a water molecule in the lower axial position. Spectroscopic data for each species are analyzed within the framework of time-dependent density functional theory (TD-DFT) to assign the major spectral features (the so-called alpha/beta, D/E, and gamma bands) and to generate experimentally validated electronic-structure descriptions. These studies reveal that the "unique" Abs spectra of MeCbl and AdoCbl, which differ considerably from the "typical" Abs spectra of H(2)OCbl(+) and CNCbl, reflect the high degree of sigma-donation from the alkyl ligand to the Co center and the consequent destabilization of all Co 3d orbitals. They reveal further that with increasing sigma-donor strength of the upper axial ligand, the contribution from the formally unoccupied Co 3d(z(2)) orbital to the HOMO increases, which induces a strong Co[bond]N(DMB) sigma-antibonding interaction, consistent with the experimentally observed lengthening of this bond from H(2)OCbl(+) to CNCbl and MeCbl. Alternatively, our spectroscopic and computational data for MeCbl and MeCbi(+) reveal that substitution of the DMB by a water molecule in the lower axial position has negligible effects on the Co[bond]C. A simple model is presented that explains why the identity of the upper axial ligand has a major effect on the Co[bond]N(ax) strength, whereas the lower axial ligand does not appreciably modulate the nature of the Co[bond]C. Implications of these results with respect to enzymatic Co[bond]C activation are discussed.

Circular Dichroism↗
PubMed2002

Systematic evaluation of rating scales for impairment and disability in Parkinson's disease.

We assessed the clinometric characteristics of rating scales used for the evaluation of motor impairment and disability of patients with Parkinson's disease (PD), conducting a systematic review of PD rating scales published from 1960 to the present. Thirty studies describing clinometrics of 11 rating scales used for PD were identified. Outcome measures included validity (including factor structure), reliability (internal consistency, inter-rater, and intrarater) and responsiveness. We traced three impairment scales (Webster, Columbia University Rating Scale [CURS] and Parkinson's Disease Impairment Scale), four disability scales (Schwab and England, Northwestern University Disability Scale [NUDS], Intermediate Scale for Assessment of PD, and Extensive Disability Scale), and four scales evaluating both impairment and disability (New York University, University of California Los Angeles, Unified Parkinson's Disease Rating Scale [UPDRS], and Short Parkinson Evaluation Scale). The scales showed large differences in the extent of representation of items related to signs considered responsive to dopaminergic treatment or to those signs that appear late in the disease course and lack responsiveness to treatment. Regardless of the scale, there was a conspicuous lack of consistency concerning inter-rater reliability of bradykinesia, tremor, and rigidity. Overall disability items displayed moderate to good inter-rater reliability. The available evidence shows that CURS, NUDS, and UPDRS have moderate to good reliability and validity. In contrast to their widespread clinical use for assessment of impairment and disability in PD, the majority of the rating scales have either not been subjected to an extensive clinometric evaluation or have demonstrated clinometric shortcomings. The CURS, NUDS, and UPDRS are the most evaluated, valid, and reliable scales currently available.

Disability Evaluation↗
PubMed2000

A challenge to the cross-cultural validity of the SF-36 health survey: factor structure in Maori, Pacific and New Zealand European ethnic groups.

This paper reports on a principal component factor analysis of the SF-36 health status questionnaire in the three major ethnic groups in New Zealand (New Zealand Europeans, Maori and Pacific). The SF-36 is hypothesised to have a two-dimensional structure with distinct (weakly correlated) mental and physical health components, and support for this structural model has generally been found cross-nationally. However, in Maori and Pacific models of health mental and physical dimensions are not generally seen as separable, or independently functioning. This raises the possibility that the questionnaire's hypothesised structural model would not be supported among Maori and Pacific ethnic groups. This study evaluated that possibility. The results of the analysis showed a similar factor structure among New Zealand Europeans, and younger Maori (<45 years) to that reported by Ware et al. for Western European countries. Among Pacific people and older Maori (45 years and over), however, the factor structure did not clearly differentiate physical and mental health components. Implications are discussed both specific to the SF-36 (and in particular the use of principal component summary scores), and more generally for the cross-cultural validity of self-reported health status measures.

Activities of Daily Living↗
PubMed2005

Heparan sulfate mimicry: a synthetic glycoconjugate that recognizes the heparin binding domain of interferon-gamma inhibits the cytokine activity.

Cell-associated heparan sulfate (HS) is endowed with the remarkable ability to bind numerous proteins. As such, it represents a unique system that integrates signaling from circulating ligands with cellular receptors. This polysaccharide is extraordinary complex, and examples that define the structure-function relationship of HS are limited. In particular, it remains difficult to understand the structures by which HS interact with proteins. Among them, interferon-gamma (IFNgamma), a dimeric cytokine, binds to a complex oligosaccharide motif encompassing a N-acetylated glucosamine-rich domain and two highly sulfated sequences, each of which binds to one IFNgamma monomer. Based on this template, we have synthesized a set of glycoconjugate mimetics and evaluated their ability to interact with IFNgamma. One of these molecules, composed of two authentic N-sulfated octasaccharides linked to each other through a 50-Angstroms-long spacer termed 2O(10), displays high affinity for the cytokine and inhibits IFNgamma-HS binding with an IC(50) of 35-40 nm. Interestingly, this molecule also inhibits the binding of IFNgamma to its cellular receptor. Thus, in addition to its ability to delocalize the cytokine from cell surface-associated HS, this compound has direct anti-IFNgamma activity. Altogether, our results represent the first synthetic HS-like molecule that targets a cytokine, strongly validating the HS structural determinants for IFNgamma recognition, providing a new strategy to inhibit IFNgamma in a number of diseases in which the cytokine has been identified as a target, and reinforcing the view that it is possible to create"tailor-made"sequences based on the HS template to isolate therapeutic activities.

Amino Acid Sequence↗
PubMed2006

Fear of movement/(re)injury in chronic pain: a psychometric assessment of the original English version of the Tampa scale for kinesiophobia (TSK).

The Tampa scale for kinesiophobia (TSK) was developed to measure fear of movement/(re)injury in chronic pain patients. Although studies of the Dutch adaptation of the TSK have identified fear of movement/(re)injury as an important predictor of chronic pain, pain-related avoidance behaviour, and disability, surprisingly little data on the psychometric properties of the original English version of the TSK are available. The present study examined the reliability, construct validity and factor structure of the TSK in a sample of chronic pain patients (n=200) presenting for an interdisciplinary functional restoration program. Consistent with prior evaluations of the Dutch version of the TSK, the present findings indicate that the English TSK possesses a high degree of internal consistency and is positively associated with related measures of fear-avoidance beliefs, pain catastrophizing, pain-related disability and general negative affect. The TSK was not related to individual differences in physical performance testing as assessed using standardised treadmill and lifting tasks. Confirmatory factor analyses suggest that the TSK is best characterized by a three-factor trait method model that includes all 17 of the original scale items and takes into account the distinction between positively and negatively keyed items. The results of the present study provide important details regarding the psychometric properties of the original English version of the TSK and suggest that it may be unnecessary to remove the negatively keyed items in an attempt to improve scale validity.

Adult↗
PubMed2002

Return to work outcomes following accident compensation corporation work capacity assessment.

AIMS: To determine the proportion of Accident Compensation Corporation (ACC) claimants who have returned to fulltime work after ceasing to receive ACC weekly compensation following Work Capacity Assessment (WCAP). To assess what factors impact on return to work. To assess whether ACC's research findings into return to work outcomes WCAP are valid. METHODS: A structured questionnaire telephone follow-up survey was conducted with ACC claimants seen for WCAP. RESULTS: 43% of those exited from ACC weekly compensation after WCAP were currently working fulltime. Claimants who had exited ACC after WCAP were significantly more likely to be working than those remaining on ACC. Claimants over 40 years of age were significantly less likely to be working. Gender, race, length of time since injury, and retraining made no difference to return to work. 80% of claimants felt that the WCAP process was unfair. CONCLUSION: Nearly half of those claimants certified as being unfit for work but now exited from ACC via WCAP were working fulltime. This may indicate that ACC's rehabilitation is successful, or that claimants tend to remain on ACC for economic rather than injury reasons, or that WCAP results in claimants returning to physically unsuitable work putting them at risk of further injury. ACC's research finding, that 79% of claimants were working after WCAP does not appear to be valid.

Adult↗
PubMed2005

The structured assessment of depression in brain-damaged individuals: translation and validation study of the Italian version.

The aim of this study was to translate the structured assessment of depression in brain-damaged individuals (SADBD) questionnaire into the Italian language, validate, and test reliability and validity of the Italian version. Consecutive patients with stroke were screened in the Department of Neurology, Avogadro University in Novara and the Department of Neurorehabilitation, Maugeri Foundation, Veruno, Italy. Thirty patients were included in the study. The internal consistency ranged between 0.78 and 0.87. The intra-rater test-retest reliability was 0.93 for BDIderived items and 0.82 for HRSD-derived items; while the inter-rater test-retest reliability was 0.94 for BDI-derived items and 0.93 for HRSD-derived items. Correlation between the SADBD diagnosis made by the physician and the nurse was 0.51; correlation between caregiver and physician diagnosis was 0.60. The Italian version of the SADBD was demonstrated to be acceptable, reliable and a valid measure of depression in patients with stroke.

Aged↗
PubMed2005

Validating the use of database potentials in protein structure determination by NMR.

The refinement of protein structures determined by nuclear magnetic resonance spectroscopy against database potentials of mean force allows for the exclusion of unfavourable conformations of the protein backbone during a structure calculation, resulting in protein structures with a marked improvement in Ramachandran statistics. In this communication, we use multiple sets of residual dipolar couplings as quality assessment criteria for several proteins and show that not only do the Ramachandran and structural quality statistics improve, but a significant improvement in the accuracy of structures is achieved upon refinement.

Data Interpretation, Statistical↗
PubMed2004

Validation of two survey diagnostic interviews among primary care attendees: a comparison of CIS-R and CIDI with SCAN ICD-10 diagnostic categories.

BACKGROUND: The most widely used survey measures in psychiatry, the Composite International Diagnostic Interview (CIDI) and the Clinical Interview Schedule-Revised (CIS-R) have generated estimates of psychiatric morbidity that show considerable variation. Doubts have been raised regarding the validity of these structured lay interviewer assessments. There have been no direct comparisons of the performances of these instruments against a common, established criterion. METHOD: A total of 105 unselected primary care attendees were each interviewed with CIDI, CIS-R and SCAN in a single sitting with random order of administration. SCAN was administered by a SCAN trained psychiatrist, and CIDI and CIS-R by a public health doctor. Concordance was estimated for all ICD-10 neurotic disorders. We assessed the overall discriminability of the CIS-R morbidity scale using a receiver operating characteristic (ROC) analysis. RESULTS: The concordance for CIDI for ICD-10 diagnoses was moderate to excellent (kappa= 0.58-0.97). Concordance for CIS-R ranged between poor and moderate (kappa = 0.10-0.65). The area under the ROC curve for the CIS-R morbidity scale with respect to any ICD-10 disorder [0.87 (95% CI 0.79-0-95)] indicated good overall discriminability, but poor sensitivity (44%) and high specificity (97%) at the usual CIS-R cut-point of 11/12. CONCLUSION: Among primary care attendees the CIDI is a highly valid assessment of common mental disorders, and the CIS-R is moderately valid. Previous studies may have underestimated validity. Against the criteria of all ICD-10 diagnoses (including less severe depressive and anxiety disorders) a much lower CIS-R cut-point is required than that which is usually advocated.

Adult↗
PubMed2001

Development and validation of the Conflict in Adolescent Dating Relationships Inventory.

Four studies examined the Conflict in Adolescent Dating Relationships Inventory (CADRI), a measure of abusive behavior among adolescent dating partners. Exploratory factor analysis was used to refine items based on high school participants with dating experience (N = 393; 49% female). Confirmatory factor analysis was used to derive and cross-validate the factor structure with participants from 10 high schools (N = 1,019, 55% female; ages 14-16). The model structure fit for all grades and both sexes, with physical abuse, verbal abuse, and threatening behavior most representative of the underlying "abuse" factor. In Studies 3 and 4, the second-order abuse factor showed acceptable test-retest reliability, partner agreement, and correlation (significant for males only) between observer ratings of dating partners' interactions and youths' CADRI scores. Results support the CADRI as a measure of abusive behavior in adolescent dating relationships.

Adolescent↗
PubMed2003

Cross-cultural adaptation and validation of the English version of the International Index of Erectile Function (IIEF) for use in Malaysia.

We adapted the English International Index of Erectile Function (IIEF) into Malay. This was difficult as many sex-related terms do not exist in colloquial Malay. In the pretest, there was no difficulty with comprehension and all subjects judged the Malay IIEF equivalent to the English IIEF. After slight modification, a final instrument was evaluated in two studies. Study A included 136 subjects. It showed that the instrument had good reliability and discriminant validity. The factor structure of the English IIEF was not reproducible. Study B included 26 ED subjects who underwent oral sildenafil therapy. The Malay IIEF was sensitive to treatment response. The area under the ROC curve of the Malay IIEF-5 was 0.86; the optimal cutoff score has a sensitivity of 85% and specificity of 75%. The results suggest that the Malay IIEF requires more work, but the Malay IIEF-5 has acceptable measurement properties to recommend its use in clinical practice and research.

Adult↗
PubMedDate not supplied

[Ambulant training programs for obese children. Criterions of comparison for the development of valid therapy recommendations].

Valid knowledge concerning structure and contents of an ambulant training program for obese children and adolescents suggested by experts is still missing. In 1999/2000, we assessed a survey based on defined criterions in the "Arbeitsgemeinschaft für pädiatrische Diäthetik (APD)" and investigated the literature to cover and to compare based on defined criterions the spectrum of ambulant treatment models in Germany to advance guidelines for therapy in obese children. 13 ambulant training programs were detected. Training of children aged 8 to 12 years and their parents based on diet, behavioural treatment and sports therapy over couple of months without great experiences and without complete financing by health insurance were in common. Time volume of the training programs widely varies. In the seven evaluated training programs, up to one third of the patients broke off, while more than two third of the children successfully finished the training programs. The comparison of the programs failed on missing data concerning the collective, missing or different evaluation criteria, sometimes low number of patients and not standardised calculation of overweight. The survey reflects the often low experiences and the heterogeneous, insufficient evaluation of ambulant treatment models in Germany and demonstrates the great requirement of research. The schedule of criterions facilitates the comparison of programs to develop valid ambulant training programs for obese children.

Adolescent↗
PubMed2007

The Adolescent Depression Rating Scale (ADRS): a validation study.

BACKGROUND: To examine the psychometric properties of the Adolescent Depression Rating Scale (ADRS), a new measure was specifically designed to evaluate adolescent depression. METHODS: The 11-item clinician-report and 44-item self-report versions of the ADRS were developed from a qualitative phase involving interviews of experts and adolescents. These two instruments were then administered to 402 French speaking adolescents with and without depressive disorders. Item distribution, internal consistency, convergent validity, discriminant validity and factorial structure were assessed. RESULTS: After reduction procedures, a 10-item clinician version and a 10-item self-report version were obtained. The ADRS demonstrated good internal consistency (alpha Cronbach coefficient >.70). It also discriminated better between adolescents with and without depression than the Hamilton Depressive Rating Scale and the Beck Depression Inventory (BDI-13). CONCLUSION: The ADRS is a useful, short, clinician-report and self-report scale to evaluate adolescent depression. Further studies to replicate our findings and evaluate ADRS sensitivity to effects of treatment and psychometric properties in populations of adolescents with several psychiatric disorders are warranted.

Adolescent↗
PubMed1998

Prevalence of mood disorders and utility of the PRIME-MD in patients undergoing radiation therapy.

PURPOSE: To validate a short, structured interview procedure that allows practicing oncologists to quickly and reliably identify mood disorders in their patients, and to estimate the prevalence and types of mood disorders in a radiation therapy patient setting, noting relationships between mood disorders and patient characteristics. METHODS: Consecutive, eligible adult patients from the practices of two radiation oncologists were administered the Primary Care Evaluation of Mental Disorders (PRIME-MD) by the treating physician. A subset of these patients was also evaluated with the SCID, administered by trained mental health care personnel. Agreement between the two instruments was examined using the kappa statistic. Prevalence of mood disorders was determined from the PRIME-MD. The significance of relationships between patient characteristics and mood disorders was examined by chi-square and ANOVA analysis, and subsequently by multivariate logistic regression analysis. RESULTS: One hundred twenty-two patients were studied. Fifty-three of these were administered the SCID. Agreement between the two instruments was very good (kappa = 0.70). A diagnosis of a depressive or anxiety disorder by the PRIME-MD was made in 59 of the 122 patients (48%, 95% confidence interval = 39%, 58%). Multivariate analysis showed that a diagnosis of a depressive mood disorder was significantly related to pain intensity and prior history of depression. CONCLUSION: We have demonstrated the validity and feasibility of the PRIME-MD administered by oncologists in making diagnoses of mood disorders. The prevalence of mood disorders in our set of patients undergoing a course of RT was nearly 50%. Future studies should describe the natural history of these disorders, and determine optimal intervention strategies.

Adult↗
PubMed2005

Measuring spiritual belief: development and standardization of a Beliefs and Values Scale.

BACKGROUND: Higher levels of religious involvement are modestly associated with better health, after taking account of other influences, such as age, sex and social support. However, little account is taken of spiritual beliefs that are not tied to personal or public religious practice. Our objective was to develop a standardized measure of spirituality for use in clinical research. METHOD: We characterized the core components of spirituality using narrative data from a purposive sample of people, some of whom were near the end of their lives. These data were developed into statements in a scale to measure strength of spiritual beliefs and its reliability, validity and factor structure were evaluated in order to reach a final version. RESULTS: Thirty-nine people took part in the qualitative study to define the nature of spirituality in their lives. These data were used to construct a 47-item instrument that was evaluated in 372 people recruited in medical and non-medical settings. Analysis of these statements led to a 24-item version that was evaluated in a further sample of 284 people recruited in similar settings. The final 20-item questionnaire performed with high test-retest and internal reliability and measures spirituality across a broad religious and non-religious perspective. CONCLUSIONS: A measure of spiritual belief that is not limited to religious thought, may contribute to research in psychiatry and medicine.

Adult↗