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PubMed1999

The Rorschach Inkblot Test: a case of overstatement?

In the 1940s, inflated claims were often made regarding the Rorschach Inkblot Test. Over half a century later, overstatements regarding the test are still common. The present article identifies problems with the Rorschach regarding norms, cultural sensitivity, interrater reliability, test-retest reliability, validity, factor structure, and accessibility of supporting studies. Contrary to overstated claims made on behalf of the Rorschach, the test continues to be a highly problematic instrument from a psychometric standpoint.

Adult↗
PubMed2006

Knowledge and attitudes about health research amongst a group of Pakistani medical students.

BACKGROUND: Health research training is an important part of medical education. This study was conducted to assess the level of knowledge and attitudes regarding health research in a group of Pakistani medical students at Aga Khan University, Karachi. METHODS: It was a cross-sectional pilot study conducted among a group of Pakistani medical students. Through stratified random sampling, a pre-tested, structured and validated questionnaire was administered to 220 medical students. Knowledge and attitudes were recorded on a scale (graduated in percentages). RESULTS: Mean scores of students were 49.0% on knowledge scale and 53.7% on attitude scale. Both knowledge and attitudes improved significantly with increasing years of study in medical college [Regression coefficient 4.10 (p-value; 0.019) and 6.67 (p-value; < 0.001) for knowledge and attitudes, respectively]. CONCLUSION: Medical students demonstrate moderate level of knowledge and attitude towards health research. Intensive training in this regard is associated with significant improvement in knowledge and attitudes of students towards health research.

Adult↗
PubMed2003

Psychometric analysis of the Psychopathic Personality Inventory (PPI) with female inmates.

This study evaluated the reliability, internal structure, and validity of the Psychopathic Personality Inventory (PPI; Lilienfeld & Andrews, 1996) among female inmates (n = 153) housed at a multilevel prison facility. Findings from this research suggested both strengths and weaknesses associated with PPI psychopathy assessment. Reliability of the PPI was supported by internal consistency analyses of scale and subscale item sets, and test-retest reliability was supported by findings obtained with a subsample (n = 36) retested an average of 49 days after initial test administration. Validity of the PPI total score was also supported by moderate to very high correlations with other self-report measures of psychopathy. Relative weaknesses of the PPI were evident by the low or negative associations among many of the PPI subscales, moderate associations that PPI total scores demonstrated with response set indexes, and the similarity of PPI total scores among female inmates and undergraduates. Findings from this research are considered in relation to possible sex differences in the expression of psychopathy and challenges associated with the assessment of the psychopathy construct with self-report methods.

Adult↗
PubMed1993

The product of the Drosophila segment polarity gene armadillo is part of a multi-protein complex resembling the vertebrate adherens junction.

Sequence similarity between the Drosophila segment polarity protein Armadillo and the vertebrate adherens junction protein beta-catenin raised the possibility that adherens junctions function in transduction of intercellular signals like that mediated by Wingless/Wnt-1. To substantiate the sequence similarity, properties of Armadillo were evaluated for consistency with a junctional role. Armadillo is part of a membrane-associated complex. This complex includes Armadillo, a glycoprotein similar in size to vertebrate cadherins, and the Drosophila homolog of alpha-catenin. Armadillo co-localizes with junctions that resemble vertebrate adherens junctions in morphology and position. These results suggest that Drosophila and vertebrate adherens junctions are structurally similar, validating use of Armadillo and its associated proteins as a model for vertebrate adherens junctions.

Animals↗
PubMed2004

Crystal structure of a group I intron splicing intermediate.

A recently reported crystal structure of an intact bacterial group I self-splicing intron in complex with both its exons provided the first molecular view into the mechanism of RNA splicing. This intron structure, which was trapped in the state prior to the exon ligation reaction, also reveals the architecture of a complex RNA fold. The majority of the intron is contained within three internally stacked, but sequence discontinuous, helical domains. Here the tertiary hydrogen bonding and stacking interactions between the domains, and the single-stranded joiner segments that bridge between them, are fully described. Features of the structure include: (1) A pseudoknot belt that circumscribes the molecule at its longitudinal midpoint; (2) two tetraloop-tetraloop receptor motifs at the peripheral edges of the structure; (3) an extensive minor groove triplex between the paired and joiner segments, P6-J6/6a and P3-J3/4, which provides the major interaction interface between the intron's two primary domains (P4-P6 and P3-P9.0); (4) a six-nucleotide J8/7 single stranded element that adopts a mu-shaped structure and twists through the active site, making critical contacts to all three helical domains; and (5) an extensive base stacking architecture that realizes 90% of all possible stacking interactions. The intron structure was validated by hydroxyl radical footprinting, where strong correlation was observed between experimental and predicted solvent accessibility. Models of the pre-first and pre-second steps of intron splicing are proposed with full-sized tRNA exons. They suggest that the tRNA undergoes substantial angular motion relative to the intron between the two steps of splicing.

Azoarcus↗
PubMed2004

Fringing-field effect in liquid-crystal beam-steering devices: an approximate analytical model.

An approximate analytical model was developed that links the fringing-field broadening of the phase profile of a liquid-crystal (LC) beam-steering device, and the resulting diffraction efficiency, to the physical parameters of the device including the cell thickness as well as the dielectric, optical, and geometrical constants of the device. The analysis includes a full solution of the Laplace equation for the LC device in which the broadening of the initial voltage profile into an effective voltage-drop profile, due to the fringing-field effect, is derived. It is shown that within the linear approximation used, the broadening of the phase profile is identical to the broadening of the effective voltage profile in the presence of the fringing field. On the basis of this model, the resulting broadening kernel of the phase profile is found to be proportional to the LC cell thickness. These results are found to be in an excellent agreement with high-precision computer simulations performed on the LC beam-steering structure, thereby validating this approximate linear model.

Journal Article↗
PubMed2006

Spectroscopic spectral-domain optical coherence microscopy.

The spectroscopic content within optical coherence tomography (OCT) data can provide a wealth of information. Spectroscopic OCT methods are frequently limited by time-frequency trade-offs that limit high spectral and spatial resolution simultaneously. We present spectroscopic spectral-domain optical coherence microscopy performed with a multimodality microscope. Restricting the spatial extent of the signal by using high-numerical-aperture optics makes high-resolution spectroscopic information accessible, facilitated with spectral-domain detection. Simultaneous acquisition of multiphoton microscopy images is used to validate tissue structure and localization of nuclei within individual cells.

Animals↗
PubMed2005

Multiple loops of the dihydropyridine receptor pore subunit are required for full-scale excitation-contraction coupling in skeletal muscle.

Understanding which cytosolic domains of the dihydropyridine receptor participate in excitation-contraction (EC) coupling is critical to validate current structural models. Here we quantified the contribution to skeletal-type EC coupling of the alpha1S (CaV1.1) II-III loop when alone or in combination with the rest of the cytosolic domains of alpha1S. Chimeras consisting of alpha1C (CaV1.2) with alpha1S substitutions at each of the interrepeat loops (I-II, II-III, and III-IV loops) and N- and C-terminal domains were evaluated in dysgenic (alpha1S-null) myotubes for phenotypic expression of skeletal-type EC coupling. Myotubes were voltage-clamped, and Ca2+ transients were measured by confocal line-scan imaging of fluo-4 fluorescence. In agreement with previous results, the alpha1C/alpha1S II-III loop chimera, but none of the other single-loop chimeras, recovered a sigmoidal fluorescence-voltage curve indicative of skeletal-type EC coupling. To quantify Ca2+ transients in the absence of inward Ca2+ current, but without changing the external solution, a mutation, E736K, was introduced into the P-loop of repeat II of alpha1C. The Ca2+ transients expressed by the alpha1C(E736K)/alpha1S II-III loop chimera were approximately 70% smaller than those expressed by the Ca2+-conducting alpha1C/alpha1S II-III variant. The low skeletal-type EC coupling expressed by the alpha1C/alpha1S II-III loop chimera was confirmed in the Ca2+-conducting alpha1C/alpha1S II-III loop variant using Cd2+ (10(-4) M) as the Ca2+ current blocker. In contrast to the behavior of the II-III loop chimera, Ca2+ transients expressed by an alpha1C/alpha1S chimera carrying all tested skeletal alpha1S domains (all alpha1S interrepeat loops, N- and C-terminus) were similar in shape and amplitude to wild-type alpha1S, and did not change in the presence of the E736K mutation or in the presence of 10(-4) M Cd2+. Controls indicated that similar dihydropyridine receptor charge movements were expressed by the non-Ca2+ permeant alpha1S(E1014K) variant, the alpha1C(E736K)/alpha1S II-III loop chimera, and the alpha1C(E736K)/alpha1S chimera carrying all tested alpha1S domains. The data indicate that the functional recovery produced by the alpha1S II-III loop is incomplete and that multiple cytosolic domains of alpha1S are necessary for a quantitative recovery of the EC-coupling phenotype of skeletal myotubes. Thus, despite the importance of the II-III loop there may be other critical determinants in alpha1S that influence the efficiency of EC coupling.

Aniline Compounds↗
PubMed2003

Insights into the biochemical and genetic basis of glucokinase activation from naturally occurring hypoglycemia mutations.

Glucokinase (GCK) is a key regulatory enzyme in the pancreatic beta-cell and catalyzes the rate-limiting step for beta-cell glucose metabolism. We report two novel GCK mutations (T65I and W99R) that have arisen de novo in two families with familial hypoglycemia. Insulin levels, although inappropriately high for the degree of hypoglycemia, remain regulated by fluctuations in glycemia, and pancreatic histology was normal. These mutations are within the recently identified heterotropic allosteric activator site in the theoretical model of human beta-cell glucokinase. Functional analysis of the purified recombinant glutathionyl S-transferase fusion proteins of T65I and W99R GCK revealed that the kinetic changes result in a relative increased activity index (a measure of the enzyme's phosphorylating potential) of 9.81 and 6.36, respectively, compared with wild-type. The predicted thresholds for glucose-stimulated insulin release using mathematical modeling were 3.1 (T65I) and 2.8 (W99R) mmol/l, which were in line with the patients' fasting glucose. In conclusion, we have identified two novel spontaneous GCK-activating mutations whose clinical phenotype clearly differs from mutations in ATP-sensitive K(+) channel genes. In vitro studies confirm the validity of structural and functional models of GCK and the putative allosteric activator site, which is a potential drug target for the treatment of type 2 diabetes.

Adolescent↗
PubMed1987

Analysis of individual, intraspecific and interspecific variability in quantitative parameters of caprine tooth enamel structure.

Qualitative and quantitative features of mammalian tooth enamel structure are increasingly being used in taxonomic and phylogenetic analyses, although the variability shown by these traits has not received adequate consideration. This study evaluates the variability displayed by nine quantitative parameters in deep, intermediate, and superficial molar enamel in the closely related bovids Ovis aries and Capra hircus. These parameters are assessed in terms of the absolute and/or relative variability evinced at a given depth within a single individual, among conspecific individuals, and between species samples. The degrees of relative variability expressed at a given depth are comparable among conspecific individuals and between taxonomic samples. Nevertheless, in many instances, there are significant differences in absolute variability amongst individuals. Also, in four parameters for which individual specimen averages could be calculated, the equality of these means among conspecifics can be rejected. Variability is not equivalent at different enamel depths. The null hypothesis of equality of individual, conspecific variances can be rejected most commonly for parameters measured in deep and superficial enamel, and coefficients of variation also tend to be higher for deep and superficial enamel than for enamel of intermediate depth. The greater variability displayed by deep and especially superficial enamel may be related to the initial onset and the terminal phase of ameloblastic secretory activity. Taxonomic and phylogenetic analyses that utilize quantitative data on enamel structure are valid only if comparisons have been made at equivalent enamel depths.

Ameloblasts↗
PubMed2003

Psychometric evaluation of the alcohol use disorders identification test and short drug abuse screening test with psychiatric patients in India.

BACKGROUND: The Alcohol Use Disorders Identification Test (AUDIT) and the short Drug Abuse Screening Test (DAST-10) are brief self-report screens for alcohol and drug problems that have not been evaluated for use with psychiatric patients in developing countries. This study was designed to evaluate the factor structure, reliability, validity, and utility of the AUDIT and the DAST-10 in an Indian psychiatric hospital. METHOD: Consecutive inpatient admissions from April to December 2001 were sampled. Patients were diagnosed with substance use disorders or psychiatric disorders according to ICD-10 criteria. All patients completed both the AUDIT and the DAST-10 during their intake evaluation. RESULTS: Of the 2286 admissions to the hospital, 1349 were enrolled in the study (30% women); 361 patients (27%) had primary substance use disorders and 988 patients (73%) had primary psychiatric disorders. Both the AUDIT and the DAST-10 were unidimensional and internally consistent. Total scores significantly differentiated the subsamples with primary substance use from those with primary psychiatric disorders (p <.0001). Using cutoff scores of >/= 8 on the AUDIT and >/= 3 on the DAST-10, only 10% (N = 100) of the psychiatric subsample exceeded either cutoff, whereas 99% (N = 358) of the addiction treatment subsample exceeded 1 or both cutoffs. Within the psychiatric subsample, 77% (N = 65) of the patients who were identified as high risk on the AUDIT did not receive an additional alcohol use disorder diagnosis at discharge, and 59% (N = 16) of those identified as high risk on the DAST-10 did not receive an additional discharge diagnosis of drug use disorder. CONCLUSION: The AUDIT and the DAST-10 demonstrate strong psychometric properties when used in an Indian psychiatric hospital. Routine use of these brief screens can facilitate detection of substance use disorders among psychiatric patients.

Adult↗
PubMed2005

Study of urban community survey in India: growing trend of high prevalence of hypertension in a developing country.

The prevalence pattern of hypertension in developing countries is different from that in the developed countries. In India, a very large, populous and typical developing country, community surveys have documented that between three and six decades, prevalence of hypertension has increased by about 30 times among urban dwellers and by about 10 times among the rural inhabitants. Various factors might have contributed to this rising trend and among others, consequences of urbanization such as change in life style pattern, diet and stress, increased population and shrinking employment have been implicated. In this paper, we study the prevalence of hypertension in an urban community of India using the JNC VII criteria, with the aim of identifying the risk factors and suggesting intervention strategies. A total of 1609 respondents out of 1662 individuals participated in our cross-sectional survey of validated and structured questionnaire followed by blood pressure measurement. Results showed pre-hypertensive levels of blood pressures among 35.8% of the participants in systolic group (120-139mm of Hg) and 47.7% in diastolic group (80-89 mm of Hg). Systolic hypertension (140 mm of Hg) was present in 40.9% and diastolic hypertension (90 mm of Hg) in 29.3% of the participants. Age and sex-specific prevalence of hypertension showed progressive rise of systolic and diastolic hypertension in women when compared to men. Men showed progressive rise in systolic hypertension beyond fifth decade of life. Bivariate analysis showed significant relationship of hypertension with age, sedentary occupation, body mass index (BMI), diet, ischemic heart disease, and smoking. Multivariate analysis revealed age and BMI as risk factors, and non-vegetarian diet as protective factor with respect to hypertension. Prevalence of prehypertensives was high among younger subjects - particularly students and laborers who need special attention. Role of non-vegetarian diet as a protective factor might have been related to fish-eating behavior of the sample population, who also use mustard oil as cooking medium - both of which have significant level of essential polyunsaturated fatty acids. The observed prevalence of hypertension in this study and other studies suggest the need for a comprehensive national policy to control hypertension in India, and, in other similar developing countries.

Journal Article↗
PubMed2000

Psychiatric epidemiology: selected recent advances and future directions.

Reviewed in this article are selected recent advances and future challenges for psychiatric epidemiology. Major advances in descriptive psychiatric epidemiology in recent years include the development of reliable and valid fully structured diagnostic interviews, the implementation of parallel cross-national surveys of the prevalences and correlates of mental disorders, and the initiation of research in clinical epidemiology. Remaining challenges include the refinement of diagnostic categories and criteria, recognition and evaluation of systematic underreporting bias in surveys of mental disorders, creation and use of accurate assessment tools for studying disorders of children, adolescents, the elderly, and people in less developed countries, and setting up systems to carry out small area estimations for needs assessment and programme planning. Advances in analytical and experimental epidemiology have been more modest. A major challenge is for psychiatric epidemiologists to increase the relevance of their analytical research to their colleagues in preventative psychiatry as well as to social policy analysts. Another challenge is to develop interventions aimed at increasing the proportion of people with mental disorders who receive treatment. Despite encouraging advances, much work still needs to be conducted before psychiatric epidemiology can realize its potential to improve the mental health of populations.

Epidemiology↗
PubMed2001

[Specific aspects of rhinomanometry in children with nasal septum deformity in the region of absorbing part of the nasal valve].

Available are original data on rhinomanometry in children with nasal septum distortion in the anterior part. Nasal patency before and after anemisation of the mucosa was measured in health and disease. Pressure in collapse of the nasal valve in children is higher than in adults, while dynamic range of the valve action in growing flow of the inspired air is more noticeable. In distortion of the nasal septum at the level of the absorbing part of the nasal valve anemisation reduces the air flow while the dynamic range is not detected. It is discussed whether early surgical intervention in children under sparing approach to nasal structures is valid.

Child↗
PubMed2003

Attributes of excellence in work-related assessments.

UNLABELLED: In order for clinicians to select and conduct work-related assessments that demonstrate 'best practice', it is necessary to identify assessments that are considered 'excellent'. OBJECTIVES: The aims of this study were to determine (1) the attributes associated with excellence for each of 3 types of work-related assessment (WPAs, FCEJs & FCENJs), and (2) the differences between the attributes associated with each type of work-related assessment. STUDY DESIGN: A questionnaire was sent to all accredited occupational or vocational rehabilitation providers in Australia, targeting occupational therapists and physiotherapists who conducted work-related assessments. The response rate was 25.3%, and 132 questionnaires were analysed. RESULTS: A MANOVA revealed that the perceived importance of 18 attributes was different between the 3 forms of work-related assessment F36, 364=6.54; p<0.001). There was a core of 7 attributes that showed no difference between assessments (accurate, comprehensive, credible, flexible, practical, safe and useful). Two attributes (generalisable and specific) were different for all 3 forms of assessment. A large group of attributes (consistent, measurable, objective, reliable, reproducible, standardised, structured and valid) demonstrated significant differences between WPAs and both forms of FCE. Relevant demonstrated significant differences between FCENJs and both WPAs and FCEJs. Reliability analysis revealed 2 constructs (dependability and utility). CONCLUSIONS: This study demonstrated that there were significant differences between 3 forms of work-related assessments (WPAs, FCEJs & FCENJs) in terms of the attributes considered necessary for excellence for each form of assessment. The attributes were considered to relate to either qualitative or quantitative features of assessment. These features were reflected in the constructs utility, which was comprised of qualitative attributes and associated with broad concepts of validity, and dependability, which was comprised of quantitative attributes and reflected concepts of reliability. There appeared to be a continuum of work-related assessment that ranged from WPAs demonstrating the most qualitative attributes to FCENJs demonstrating the most quantitative features.

Analysis of Variance↗
PubMed2004

3-D simulation of the St. Jude Medical bileaflet valve opening process: fluid-structure interaction study and experimental validation.

BACKGROUND AND AIM OF THE STUDY: Simulation of the opening and closure dynamics of a mechanical valve through a moving deforming mesh algorithm presents a challenge because of the large rotations of the leaflet and of the small gaps between the housing and the leaflets, which make remeshing a critical issue. The present study offers a computational approach to the simulation of valve leaflet motion during the opening process, together with an experimental set-up for validation of the model. METHODS: A fully 3-D simulation of the 27 mm St. Jude Medical Hemodynamic Plus mechanical valve was performed using the computational code, Fluent. Interaction between the leaflet and fluid was simulated through customized user subroutines which, according to a weakly coupled approach, update the leaflet velocities through subsequent time steps by means of an under-relaxation procedure. A parallel, experimental test was defined to collect data for the set-up of simulations and for validation purposes. RESULTS: The computed leaflet velocity and angular displacement compared well with experimental data. The model captured the main features of the opening process, and did so also from a quantitative viewpoint. Nonetheless, some discrepancies were observed, including a delay of approximately 7 ms in the computed leaflet displacement and an underestimation by approximately 7% of the maximum computed leaflet velocity. CONCLUSION: The weakly coupled approach adopted here limited computational costs, thus allowing the simulation of a fully 3-D realistic mechanical valve within 154 CPU hours at minimal computational costs. No significant drawbacks were raised in comparison with the fully coupled approach. The opening process delay was similar to that reported previously, and cannot be ascribed to the weakly coupled approach adopted here.

Biomechanical Phenomena↗
PubMedDate not supplied

A multicentric study on epidemiology of chronic obstructive pulmonary disease and its relationship with tobacco smoking and environmental tobacco smoke exposure.

INTRODUCTION: Population prevalence of chronic obstructive pulmonary disease (COPD) and its relationship with tobacco smoking, environmental tobacco smoke (ETS) exposure and other variables were studied in adult subjects of 35 years and above at four different centres in India. Question-items for the diagnosis of COPD were included in the questionnaire used for the field study on asthma epidemiology. METHODS: Field surveys were conducted in both the urban and the rural populations at Bangalore, Chandigarh, Delhi and Kanpur with the help of a structured and validated questionnaire for diagnosis of asthma and COPD. Separate sets of questions were used for the diagnoses of the two diseases. A two-stage stratified sample design was employed where a village or an urban locality formed the first stage unit and a household formed the second stage unit. A uniform methodology was used at all the four centres and the analyses were done at the central coordinating centre--Chandigarh. Chronic obstructive pulmonary disease, defined by chronic bronchitis (CB) criteria, was diagnosed from the presence of cough and expectoration on most of the days for at least three months in a year for two consecutive years or more. RESULTS: Chronic obstructive pulmonary disease was diagnosed in 4.1% of 35295 subjects, with a male to female ratio of 1.56:1 and a smoker to nonsmoker ratio of 2.65: 1. Prevalence among bidi and cigarette smokers was 8.2% and 5.9%, respectively. Odds ratio (OR) for COPD was higher for men, elderly individuals, lower socio-economic status and urban (or mixed) residence. Environmental tobacco smoke exposure among nonsmokers had an OR of 1.4(95% CI 1.21-1.61). Combined exposure to both ETS and solid fuel combustion had higher OR than for ETS exposure alone. CONCLUSIONS: Population prevalence of COPD is very high in India with some centre to centre differences. Smoking of both bidis and cigarettes, and ETS exposure among nonsmokers, were two important risk factors at all centres. It is important to employ uniform methodology for assessment of national burden and disease-surveillance programme.

Adult↗
PubMedDate not supplied

[Dimensions of personality disorders and neurophysiological correlates].

INTRODUCTION: To objective is to identify the factorial structure underlying personality disorders, using clinical and personality measures, and to check whether the resulting structure is valid and theoretically comprehensible, using neurocognitive and psychophysiological measures for establishing possible differences between the factors. METHOD: From the data obtained with the scales MCMI-II and BFQ administered to a sample of 87 subjects diagnosed as a case of any clinical category of DSM-IV personality disorders, and 17 normal controls, we carried out first-order and second-order factor analyses. RESULTS: Five first-order factors (designated as aggressive personality, personality with social deficit, non-pathological personality, obsessive personality and non-assertive personality) and three second-order factors (non-pathological/obsessive personality) were found. CONCLUSIONS: On studying the second-order factors in relation to neurocognitive and psychophysiological measures, it was found that socially-inhibited and non-assertive personalities (factor 1) are characterized by specific neuropsychological deficits in sustained attention; that aggressive personalities (factor 2) are characterized by impulsiveness and deficit in concepts formation; and that in non-pathological personalities with obsessive traits (factor 3), as obsessiveness increases, subjects present less efficacy in sustained attention tasks and greater psychogalvanic response to stress.

Adult↗