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At least 289 records · Page 16Linked to original sources

Improved detection of HIV-2 DNA in clinical samples using a nested primer-based polymerase chain reaction.

A two-step polymerase chain reaction (PCR), with four double (nested) primer pairs, used for the detection of HIV-2 in clinical samples is described. With these four nested primer pairs we could detect HIV-2 DNA in 17 of 17 virus isolates and in blood mononuclear cell samples from 31 of 37 (83.7%) seropositive individuals after ethidium bromide staining of the amplified DNA. The nested primer PCR was also compared with a single primer pair-based PCR followed by hybridization. The sensitivities of the two methods were almost equal, but the nested primer PCR offered obvious technical advantages.

Adolescent↗

Development of a real-time PCR assay for rapid identification of methicillin-resistant Staphylococcus aureus from clinical samples.

A major drawback of mecA PCR to detect methicillin-resistant Staphylococcus aureus (MRSA) directly from patient materials is the high frequency of methicillin-resistant coagulase-negative staphylococci. Therefore, a reliable detection method for MRSA from clinical samples using real-time PCR was developed. The PCR assay targeting the integration site (orfX) of the staphylococcal cassette chromosome mec (SCCmec) was evaluated in MRSA SCCmec reference strains (n = 9), MRSA ST strains (n = 16) and clinical isolates of MRSA (n = 124), MSSA (n = 53), methicillin-resistant coagulase-negative staphylococci (n = 47), and methicillin-susceptible, coagulase-negative staphylococci (n = 32). The diagnostic values of the assay were 98% sensitivity and 100% specificity. Furthermore, the PCR detection method was evaluated with 60 swabs from different body sites which were incubated overnight in brain-heart infusion. The PCR gave positive results for 27 of 29 swabs which were found to contain MRSA by conventional methods. The diagnostic values of the PCR assay for these samples were 93% sensitivity and 100% specificity. To determine the in vitro sensitivity of the assay, swabs were inoculated with serially diluted bacterial suspensions. After overnight enrichment the detection limit of the PCR was less than 10 CFU/swab. This new real-time PCR assay proved to be a fast, sensitive and specific tool for MRSA detection in a routine microbiological laboratory.

Anti-Bacterial Agents↗

High-throughput polymerase chain reaction analysis of clinical samples by capillary electrophoresis with UV detection.

Routine genetic analysis of large numbers of individuals by polymerase chain reaction (PCR) using capillary electrophoresis is often restricted by the low throughput of standard protocols and the tedious sample preparation process. Here, we demonstrate that capillary electrophoresis with UV detection can be used in PCR-based DNA analysis starting from clinical samples without purification or complicated sample manipulation. After PCR reaction using cheek cells, blood, or HIV-1 gag DNA, the reaction mixtures were injected into a capillary array either on-line or off-line by base stacking. The use of multiplexed absorption detection and the elimination of any purification steps both before and after PCR reaction can potentially provide significant benefits compared to current methods for DNA analysis with regard to time, cost, and labor.

DNA↗

The Key Behaviors Change Inventory and executive functioning in an elderly clinic sample.

The Key Behaviors Change Inventory (KBCI) was developed to assess executive, behavioral, and emotional functioning following brain insults and to track the course of recovery. The purpose of this study was to investigate, in an elderly memory disorder clinic sample, the convergent and discriminant validity of the KBCI by examining the relationships between various measures of executive functioning and the KBCI scales that theoretically relate to executive functions. The KBCI was administered to the caregivers of 97 consecutive patients who came to a memory disorders clinic seeking services. The KBCI scales of Inattention, Apathy, Unawareness of Problems, and Communication Problems were significantly correlated with cognitive measures of executive functioning but not with measures of memory, visuospatial abilities or global cognitive functioning. In contrast, KBCI scales of Interpersonal Difficulties, Somatic Difficulties, and Emotional Adjustment were not related to any cognitive measures, either executive or nonexecutive. Contrary to predicted findings, the Impulsivity Scale was not associated with cognitive measures of executive functioning. This lack of relationship most likely reflects the failure to include executive measures of orbitofrontal functioning in this study. Results provide convergent and discriminant validity support for the KBCI. The KBCI may be a useful tool for assessing and tracking the executive, behavioral, and emotional sequelae of neurologic disorders.

Adaptation, Psychological↗

Psychological health in a non-clinical sample of obese women.

OBJECTIVES: The relationship between obesity and psychological health remains unclear. The aims of this study were to evaluate the effect of obesity on the psychological health of a non-clinical sample of obese women, to investigate binge eating in this group, and to examine the predictors of psychological distress. DESIGN: A cross-sectional comparison of women divided into three obesity groups (body mass index (BMI)= 30-34.9, 35-39.9, > or = 40) was used. PARTICIPANTS: 179 women with a BMI > 30 (mean age 45 y) returned a questionnaire included in a subscriber-only magazine for women of size 16+. MEASURES: The questionnaire asked for information on demographics, weight history and eating behaviour, and included established self-report measures of body shape assessment, body shape satisfaction, dietary restraint, mental health state and self-esteem. RESULTS: The heaviest women (BMI > 40) did not differ on measures of mental health, but expressed the greatest dissatisfaction with their body weight, shape and appearance, and had the lowest self-esteem. Frequent binge eating was reported by 25% of all women. Self-esteem and peer relationships, but not body weight, were highly significant negative predictors of poor mental health. CONCLUSIONS: Poor mental health is not the inevitable consequence even of the most extreme obesity, but is related to both low self-esteem and poor peer relationships. These, and problems with eating control, are features of psychological morbidity that require recognition and therapeutic attention.

Adolescent↗

Antifungal susceptibility of 596 Aspergillus fumigatus strains isolated from outdoor air, hospital air, and clinical samples: analysis by site of isolation.

We analyzed the activities of six antifungal drugs (amphotericin B, itraconazole, voriconazole, posaconazole, caspofungin, and micafungin) against 596 Aspergillus fumigatus strains isolated from outdoor air, hospital air, and clinical samples. We did not find differences among the susceptibilities by site of isolation.

Air Microbiology↗

The positive and negative affect schedule (PANAS): construct validity, measurement properties and normative data in a large non-clinical sample.

OBJECTIVES: To evaluate the reliability and validity of the PANAS (Watson, Clark, & Tellegen, 1988b) and provide normative data. DESIGN: Cross-sectional and correlational. METHOD: The PANAS was administered to a non-clinical sample, broadly representative of the general adult UK population (N = 1,003). Competing models of the latent structure of the PANAS were evaluated using confirmatory factor analysis. Regression and correlational analysis were used to determine the influence of demographic variables on PANAS scores as well as the relationship between the PANAS with measures of depression and anxiety (the HADS and the DASS). RESULTS: The best-fitting model (robust comparative fit index = .94) of the latent structure of the PANAS consisted of two correlated factors corresponding to the PA and NA scales, and permitted correlated error between items drawn from the same mood subcategories (Zevon & Tellegen, 1982). Demographic variables had only very modest influences on PANAS scores and the PANAS exhibited measurement invariance across demographic subgroups. The reliability of the PANAS was high, and the pattern of relationships between the PANAS and the DASS and HADS were consistent with tripartite theory. CONCLUSION: The PANAS is a reliable and valid measure of the constructs it was intended to assess, although the hypothesis of complete independence between PA and NA must be rejected. The utility of this measure is enhanced by the provision of large-scale normative data.

Adolescent↗

The validity of the five-factor model prototypes for personality disorders in two clinical samples.

The authors examined the validity of D. R. Lynam and T. A. Widiger's (2001) prototypes for personality disorders (PDs) derived from the facets of the 5-factor model (FFM) of personality in 2 clinical samples. In the 1st sample (N = 94), there was good agreement between the prototypes generated by experts and the profiles reported by patients. These FFM PD similarity scores also demonstrated good convergent and discriminant validity with results from a semistructured interview and a self-report measure of Axis II pathology. In the 2nd sample (N = 132), the FFM PD similarity scores demonstrated excellent longitudinal stability and good predictive validity with regard to consensus ratings of PD features. The implications of these findings are discussed.

Adolescent↗

Molecular characterization of human enteroviruses in clinical samples: comparison between VP2, VP1, and RNA polymerase regions using RT nested PCR assays and direct sequencing of products.

Three nested RT-PCR assays were developed to permit sensitive typing of enteroviruses directly from clinical samples. These assays amplified short fragments from different genomic regions codifying for three proteins: VP2, VP1, and RNA polymerase. Given that enteroviruses have a high rate of degeneration within target codons among serotypes, the primers used consisted of mixed base and deoxyinosine residues. These techniques detected at 0.03-0.003 TCID50 of prototype Poliovirus 1 and Echovirus 30. They were used to characterize the enteroviral RNA detected in 18 CSF, stool, and throw swab samples and in 8 enterovirus isolates from patients with several syndromes. Phylogenetic analysis in each independent sequenced region grouped the enterovirus into four clusters, enabling genetic classification. A comparative study was performed among the 26 sequences obtained after direct sequencing of products with those available in the nucleotide databases. The efficiency of each assay for enterovirus identification was evaluated by both distance (Clustal) and similarity (M-NW) indices. Comparative results obtained independently in the three regions showed the highest yield of correlation between nucleotide sequences of all prototype serotypes and the analyzed genotypes in the VP1 region (26/26, 100% Clustal; 22/26, 85% M-NW). Conversely, the VP2 region failed to identify some of the circulating enteroviruses (17/26, 65% Clustal; 16/26, 62% M-NW). Using the RNA polymerase region, sequences from samples and isolates were associated with prototype strains whenever these were available (20/21, 95% Clustal; 12/21, 57% M-NW). These assays were useful for molecular identification of enterovirus directly from samples even when isolation was not possible.

Capsid↗

Low prevalence of vancomycin-resistant enterococci in clinical samples from hospitalized patients of the Canary Islands, Spain.

Over the last decade vancomycin-resistant enterococci (VRE) have emerged as nosocomial pathogens. The aim of this study was to determine the prevalence of VRE in clinical samples from hospitalized patients in the Canary Islands. From April to November 2000, 437 enterococci were isolated from patients hospitalized at the four main health care centers in those islands. Identification to the species level was performed with the GPS-TA (Vitek 1) or the Wider I system. A PCR assay was used to determine the genotype of glycopeptide resistance ( vanA, vanB, vanC1, and vanC2/C3 genes). Only three (0.7%) VRE were detected: one vanA Enterococcus faecalis, and two vanC1 Enterococcus gallinarum. To our knowledge, this is the first VRE study carried out in the Canary Islands hospitals, and the results showed a low prevalence of VRE.

Enterococcus↗

A high performance liquid chromatography system for the simultaneous assay of some antibiotics commonly found in combination in clinical samples.

Using a single reversed-phase HPLC column with a mobile phase of methanol and 100 mM phosphate buffer, concentrations of seven antibiotics (chloramphenicol, metronidazole, cefuroxime, cephalexin, ceftazidime, ampicillin and benzylpenicillin) which are commonly used clinically in combinations of two or more, can be assayed and results reported within one hour. No endogenous interference was detected in serum, urine or cerebrospinal fluid. The method was highly specific even in the presence of other drugs and metabolites commonly found in clinical samples and provides a rapid, simple technique suitable for use in routine microbiological practice.

Anti-Bacterial Agents↗

Reverse transcription-competitive multiplex PCR improves quantification of mRNA in clinical samples--application to the low abundance CFTR mRNA.

BACKGROUND: To monitor gene therapy, we wished to quantify cystic fibrosis transmembrane conductance regulator (CFTR) mRNA. We developed a PCR-based method to measure CFTR mRNA in clinical samples. METHODS: Expression was determined by reverse transcription-competitive multiplex PCR (RCMP) for CFTR and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) transcripts, and for serial dilutions of two internal cDNA standards consisting of CFTR and GAPDH mutants containing short deletions. The RCMP used simultaneous amplification of the gene of interest with a reporter gene in one reaction tube. The expression of CFTR was calculated with reference to the amount of GAPDH to correct for variations in initial RNA loading. RESULTS: Amplification of cDNAs derived from different amounts of RNA (1-4 microgram) gave similar GAPDH/CFTR ratios, with a coefficient of variation (CV) below 7.5%. RCMP was applied on nasal and bronchial brushings and shows a high variability of CFTR expression in non-cystic fibrosis donors. CONCLUSION: This method is precise and reproducible and advantageous for use with limited amounts of tissue, such as from biopsies or from nasal or bronchial brushings.

Bronchi↗

[Molecular identification of Candida albicans and Candida dubliniensis strains isolated from clinical samples].

Candida dubliniensis is a recently identified opportunistic pathogen, which has close phylogenetic relation with Candida albicans. The aim of this study was the genotypic differentiation of 55 germ tube-positive Candida strains isolated from clinical specimens (30 blood, 25 throat swab specimens). The isolates were phenotypically identified by API ID 32C system, and genotypically identified by using polymerase chain reaction-restriction fragment lenght polymorphism (PCR-RFLP) method. Initially ITS2 region has been amplified by using universal fungal primers with PCR. After amplification and purification of approximately 340 base pair products, they were treated with species-specific restriction enzymes (MspA1 I and BsmAI for C. albicans and C. dubliniensis, respectively). As a result, API ID 32C system identified 52 (94.5%) isolates as C. albicans and 3 (5.5%) isolates as C. dubliniensis, whereas PCR-RFLP analysis yielded 50 (90.9%) C. albicans and 5 (9.1%) C. dubliniensis. It can be concluded that PCR-RFLP method may be used for the differentiation of C. dubliniensis and C. albicans isolates in clinical samples.

Candida↗

Enterocytozoon bieneusi (microsporidia) in clinical samples from immunocompetent individuals in Tenerife, Canary Islands, Spain.

Microsporidia are newly emerging pathogens of humans and animals, with Enterocytozoon bieneusi being the most common causal agent in human microsporidiosis. To determine the presence of E. bieneusi, 273 clinical samples (40 urine, 156 stools, 37 sputum, 9 bronchial aspirates, 5 bronchial washes and 26 pleural fluids) from immunocompetent patients, mainly suffering diarrhoea or pneumonia, in Tenerife, Canary Islands, Spain were analysed using light microscopy after staining with Weber's chromotrope and by PCR/hybridisation with a specific probe designed to increase the sensitivity of the identification. In this study, detection of E. bieneusi after PCR/hybridisation is reported in 18 (11.54%) of 156 stool samples, 1 (2.5%) of 40 urine samples and 6 (16.22%) of 37 sputum samples. To our knowledge, these are the first reports of E. bieneusi in this subtropical region, showing the increased importance of these parasites as emerging pathogens worldwide.

Adolescent↗

Autobiographical memory and emotion in a non-clinical sample of women with and without a reported history of childhood sexual abuse.

OBJECTIVES: This study focused on the relationship between reported CSA history, subsequent autobiographical memory retrieval, intrusive and dysfunctional thoughts, and mood in a non-clinical sample. The main hypothesis was that specificity in autobiographical memory recall would differentiate between women with a reported history of CSA and those without, and that this finding would be independent of current mood. DESIGN: A between-group comparison of women (female undergraduates) with and without a reported history of CSA. Within group correlations were also examined for the reported CSA group. METHOD: Participants were 79 female students, of whom 22 (28%) reported a history of CSA. All participants completed questionnaires requesting information on a history of CSA, a questionnaire version of the autobiographical memory test, the profile of mood states, the dysfunctional attitude scale, and the impact of events scale. RESULTS: The reported CSA group gave significantly fewer specific autobiographical memories, were significantly more anxious, depressed and angry, and held more dysfunctional beliefs than the comparison group. However, specificity of memory was not correlated with the degree of this mood disturbance or with the impact of event scale or extent of dysfunctional beliefs. CONCLUSIONS: Models of the long-term effects of CSA should incorporate the effects CSA may have on subsequent retrieval for memory of non-abuse events. To improve treatment outcome, clinicians may have to directly address these deficits in therapy.

Adolescent↗

Schizotypal dimensions in normals and schizophrenic patients: a comparison with other clinical samples.

Schizotypy is usually referred to as a "liability" to schizophrenia, but it could also be more generally referred to as nonspecific "psychosis-proneness". This study examined the structure of schizotypy in a normal sample and in a sample of schizophrenics through the administration of the Schizotypal Personality Questionnaire (SPQ). Within a "fully dimensional" approach to psychiatric disorders, this study also compared SPQ scores in clinical samples of subjects with bipolar, unipolar and obsessive-compulsive (OCD) disorders. The results suggested that the disorganized three-factor model, Cognitive-Perceptual, Interpersonal Deficits and Disorganization, underlies individual differences across samples of normal and schizophrenic patients. Furthermore, the SPQ measures discriminated schizophrenia and bipolars from major depression but not from OCD.

Adult↗

Factors associated with pain complaints in a clinical sample of postmenopausal women.

The aims of this study were to evaluate the relationships occurring between pain complaints and postmenopausal status, and to look at the correlation between such complaints and other symptoms commonly related to the climacterium. A clinical sample of 99 consecutive postmenopausal patients requiring medical help were studied: 36 complained of muscle-skeletal pains whereas 33 presented with headache limiting daily activity. Climacteric syndrome, level of distress, coping style and bone mineral density were assessed with appropriate questionnaires and instruments. Neither bone mineral density, nor body mass index nor time since menopause were associated with either headaches or muscle-skeletal pains. According to the logistic regression being younger, being without a job, suffering from insomnia and having a lower ability in self-support by the means of comforting ideas predicts suffering from headache. A high level of distress and an avoidance behavior to problem facing predict the presence of pain complaints. In such cases the ineffectiveness of the coping mechanism (i.e. avoid the problem) could be the reason for the increased level of psychological distress. These findings indicate that complaining of pains or headache is not dependent upon postmenopausal status. Individual coping strategies and their effectiveness seem the main reasons for the presence of disabling musculoskeletal pains or headache.

Activities of Daily Living↗

Diagnostic discrimination of live attenuated influenza vaccine strains and community-acquired pathogenic strains in clinical samples.

Live vaccines can generate false-positive results on common influenza assays including reverse transcriptase-PCR (RT-PCR), culture and antigen tests. This threatens the integrity of epidemiological data and may misdirect treatment and control efforts. We report the development of RT-PCR tests that distinguish live FluMist vaccine (FMV) strains from circulating influenza strains in clinical samples. Primers were validated using influenza-positive samples from unvaccinated patients, packaged FMV, and one PCR-positive asymptomatic vaccine. Furthermore, the assay was used to experimentally test our lab's collection of influenza-positive samples from the 2004-05 and 2005-06 influenza seasons and several 2005 preseason isolates to determine the rate of vaccine-derived false-positive results under differing epidemiological conditions. Analytical and clinical validations show that the assay is both sensitive and specific. Experimental results demonstrate that 51 out of 51 influenza-positive samples collected during influenza season from ill, previously-vaccinated military personnel represent real infections with circulating strains. Finally, the assay shows that four preseason influenza-positive samples were false positives resulting from vaccine shedding. The vaccine-discriminatory RT-PCR methods described here provide the first test designed to distinguish FMV strains from circulating strains. The results show that the test is effective, and demonstrate the importance of such tests in the age of live vaccines.

Base Sequence↗