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PubMedDate not supplied

Menstrual cycle symptoms: comparison of a non-clinical sample with a patient group.

This study compared findings of a community group of women (n = 32), who claimed they did not require help for menstrual cycle complaints, with a patient group (n = 75) with confirmed premenstrual syndrome (PMS). Subjects completed a battery of psychological tests to identify personality characteristics, levels of depression, anxiety, stress and marital adjustment. Menstrual cycle symptoms were assessed with the Menstrual Distress Questionnaire (MDQ, Moos, 1985) during follicular (day 6-8) and premenstrual phases (day 26-28) of two adjusted cycles and with daily symptom ratings. Daily 24-h urines were collected for oestradiol and pregnanediol levels for one cycle. After prospective assessment, the non-clinical sample were differentiated into those with pronounced cyclical symptom changes (Hi-volunteers, n = 13) and others with minimal cyclical changes (Lo-volunteers, n = 19). The total non-clinical sample could be distinguished from the patient group on depression, stress, and self-esteem scores. The non-clinical subgroup with pronounced cyclical symptoms is proposed as an 'at-risk' group for future treatment seeking.

Adaptation, Psychological↗
PubMed2005

Neuroticism and introversion: a risky combination for disordered eating among a non-clinical sample of undergraduate women.

Recent evidence suggests that people who score low on measures of sociability may be at risk for certain types of psychopathology, including mood and anxiety disorders. In an attempt to extend these findings to other forms of psychopathology, we examined levels of neuroticism and extraversion in relation to eating problems in a non-clinical sample of undergraduate women. The Eysenck Personality Questionnaire (EPQ), Eating Disorders Inventory (EDI), and the Eating Attitudes Test (EAT-26) were completed by 196 first-year undergraduate females. We found that high neuroticism was related to high scores on both of the EDI subscales (Bulimia and Drive for Thinness) as well as high scores on the EAT-26 measure, replicating previous work. In addition, neuroticism served as a moderator such that lower extraversion (i.e., introversion) was related to greater disordered eating, but only for those women who scored high on neuroticism. Thus, a combination of neuroticism and introversion may be a risk-factor for symptoms of eating disorders in a non-clinical sample of university women.

Adult↗
PubMed2001

Detection of peptostreptococcus micros DNA in clinical samples by PCR.

Peptostreptococcus micros is a gram-positive anaerobic coccus which, although considered to be a natural commensal of the human oral cavity, is associated with periodontal, endodontal and peritonsillar infections. Identification of the organism has to date relied upon conventional culture methods and biochemical analyses. The purpose of this study was to develop a PCR method for rapid and specific identification of this organism in clinical samples. A pair of primers was selected, each of which was specific at the 3' end for P. micros DNA; they were used in the PCR assay, resulting in a 1074-bp product. The primers were shown to be specific for P. micros DNA as no PCR products were obtained when genomic DNA extracts from a wide range of other Peptostreptococcus species and other oral bacteria were used as templates. The PCR assay was then applied to the identification of P. micros DNA in subgingival plaque samples from adult periodontitis patients and pus samples from subjects with acute dento-alveolar abscesses. Confirmation of specific amplification of P. micros DNA was obtained by digestion of PCR products with the restriction endonuclease RsaI, which gives a unique restriction profile for P. micros, and DNA sequencing. Sixty-eight subgingival plaque samples from 18 patients were analysed, of which 19 (28%) were positive for P. micros DNA; the proportion of patients carrying P. micros DNA in at least one sampled site was 11 (61%) of 18. Twenty (71%) of 28 pus samples analysed by PCR contained P. micros DNA. These results confirm that P. micros may be involved in the aetiology of acute dentoalveolar abscesses and adult periodontitis. The PCR assay provides a more rapid and reliable alternative to conventional methods for identification of P. micros in clinical samples.

Adult↗
PubMed2004

Development of a N gene-based PCR-ELISA for detection of Peste-des-petits-ruminants virus in clinical samples.

A highly sensitive N gene-based PCR-ELISA for the detection of Peste-des-petits-ruminants virus (PPRV) was developed. The RT-PCR yielded a digoxigenin (DIG)-labeled product of 336 bp comprising a sequence from PPRV N gene, which was then detected by ELISA. The assay could detect the viral RNA in PPRV-infected tissue culture fluids with a titer as low as 0.1 TCID(50)/ml. The assay is 10,000 times more sensitive than a classical RT-PCR combined with agarose gel electrophoresis. The assay could detect the virus in the clinical samples, which were negative by conventional sandwich ELISA (S-ELISA). The percentage positivity of the assay in detecting the virus in clinical samples was 66.2% compared to 48.6% for S-ELISA. The assay was more sensitive than S-ELISA also in detecting the virus in early as well as late phases of the disease. In addition, the assay could also be used for differential diagnosis of PPRV and Rinderpest virus (RPV).

Animals↗
PubMed2003

Analysis of human herpesvirus-6 IE1 sequence variation in clinical samples.

Herpesvirus immediate early (IE) proteins are known to play key roles in establishing productive infections, regulating reactivation from latency, and creating a cellular environment favourable to viral replication. Human herpesvirus-6 (HHV-6) IE genes have not been studied as intensively as their homologues in the prototype betaherpesvirus human cytomegalovirus (HCMV). Whilst the HCMV IE1 gene is relatively conserved, early studies indicated that HHV-6 IE1 exhibited a high level of sequence variation between HHV-6A and HHV-6B isolates, although the observation was based primarily on virus stocks that had been isolated and propagated in vitro. In this study, we investigated the level of HHV-6 IE1 sequence variation in vivo by direct sequencing of circulating virus in clinical samples without prior in vitro culture. Sequences exactly matching those reported for reference HHV-6 isolates were identified in clinical samples, thus the HHV-6 laboratory strains used in the majority of in vitro studies appear to be representative of virus circulating in vivo with respect to the IE1 gene. The HHV-6 IE1 sequence is also conserved in reference strains that had been passaged extensively in vitro. The high degree of divergence between variant A and B type IE1 sequences was confirmed, but interestingly HHV-6B IE1 sequences were observed to further segregate into two distinct subgroups, with the laboratory strains Z29 and HST representative of these two subgroups. Within each HHV-6B subgroup, a remarkably high level of homology was observed. Thus the HHV-6 IE1 sequence appears highly stable, underlining its potential importance to the viral life cycle.

Adult↗
PubMed1998

Rapid detection of Candida albicans in clinical samples by DNA amplification of common regions from C. albicans-secreted aspartic proteinase genes.

Laboratory diagnosis based on genomic amplification methods such as PCR may provide an alternative and more sensitive method than conventional culture for the early detection of deep-seated candidiasis, an increasing cause of morbidity and mortality among immunocompromised patients. A novel method of DNA extraction from clinical samples based on treatment with proteinase K and isolation of DNA on a silica membrane was developed. The targets used for DNA amplification were the Candida albicans-secreted aspartic proteinase (SAP) genes, a multiple-gene family of at least seven members in C. albicans. A single pair of primers was designed in order to detect six of these SAP genes and, subsequently, to increase the sensitivity of the test. Detection of the PCR product by enzyme-linked immunosorbent assay was found to be as sensitive as Southern blotting with an SAP-labeled probe. The sensitivity of the assay was 1 cell/ml from serially diluted Candida cultures and 1 to 4 cells/ml from seeded blood specimens. The sensitivity and specificity of the present assay were tested in a retrospective study performed blindly with 156 clinical samples and were 100 and 98%, respectively, compared with the results of culture. For the subset of blood culture samples (n = 124), the sensitivity and the specificity were 100%. The two false-positive PCR samples came from patients treated with azole antifungal agents, indicating that PCR was probably able to detect damaged organisms that could not be recovered by culture.

Aspartic Acid Endopeptidases↗
PubMed2005

Fluorescent in situ hybridization with specific DNA probes offers adequate detection of Enterococcus faecalis and Enterococcus faecium in clinical samples.

Enterococcus faecalis and Enterococcus faecium are among the leading causes of hospital-acquired infections. Reliable and quick identification of E. faecalis and E. faecium is important for accurate treatment and understanding their role in the pathogenesis of infections. Fluorescent in situ hybridization (FISH) of whole bacterial cells with oligonucleotides targeted at the 16S rRNA molecule leads to a reduced time to identification. In clinical practice, FISH therefore can be used in situations in which quick identification is necessary for optimal treatment of the patient. Furthermore, the abundance, spatial distribution and bacterial cell morphology can be observed in situ. This report describes the design of two fluorescent-labelled oligonucleotides that, respectively, detect the 16S rRNA of E. faecalis and the 16S rRNA of E. faecium, Enterococcus hirae, Enterococcus mundtii, Enterococcus villorum and Enterococcus saccharolyticus. Different protocols for the application of these oligonucleotides with FISH in different clinical samples such as faeces or blood cultures are given. Enterococci in a biofilm attached to a biomaterial were also visualized. Embedding of the biomaterial preserved the morphology and therefore the architecture of the biofilm could be observed. The usefulness of other studies describing FISH for detection of enterococci is generally hampered by the fact that they have only focused on one material and one protocol to detect the enterococci. However, the results of this study show that the probes can be used both in the routine laboratory to detect and determine the enterococcal species in different clinical samples and in a research setting to enumerate and detect the enterococci in their physical environment.

Biocompatible Materials↗
PubMed2006

The post-event processing questionnaire in a clinical sample with social phobia.

Post-event processing (PEP) involving rumination about perceived inadequacy in a past social situation has been proposed as an important maintaining factor in social phobia. The three aims of this study were to examine (a) the factor structure and internal reliability of a modified version of the Post-Event Processing Questionnaire [Rachman, S., Grüter-Andrew, J., & Shafran, R. (2000). Post-event processing in social anxiety. Behaviour Research and Therapy, 38, 611-617] in a clinical sample with social phobia (N=117), (b) the associations between PEP and symptoms of anxiety and depression, and (c) the relationship between perspective-taking ('field' and 'observer') and anxiety. Principal axis factor analysis yielded a highly reliable one-factor solution in our clinical sample, which generally replicated Rachman et al.'s findings with a sample of undergraduate students. PEP was most strongly and independently associated with state anxiety when depression, general anxiety and stress were controlled for. Contrary to expectations, PEP was not related to measures of social anxiety. The relationship between perspective-taking and anxiety was more complex than expected. Theoretical implications of these findings are discussed with reference to contemporary cognitive-behavioural models of social phobia.

Adult↗
PubMed1996

Detection of the 5' region of the rubella virus genome in clinical samples by polymerase chain reaction.

BACKGROUND: Maternal rubella infection in early pregnancy has a high probability of causing congenital rubella infection. In some cases it may be difficult to establish the risk of congenital infection and polymerase chain reaction (PCR) based techniques are therefore being applied to prenatal diagnosis. OBJECTIVES: To investigate whether the non-structural region of the rubella virus (RV) genome can be detected in clinical samples using PCR, thereby providing a prenatal assay independent of those currently used to detect the structural protein coding region. STUDY DESIGN: Oligonucleotide primers coding for RV nucleotides 1-17 and 541-558 from the non-structural protein coding region of the RV genome were used in a reverse transcription polymerase chain reaction (NS RT-PCR) to amplify 558 nucleotides of RV cDNA. Amplification of RV specific sequences was confirmed by Southern hybridization. RESULTS: The specificity of the assay was confirmed by the detection of RV RNA from both wild-type and vaccine strains of RV, pharyngeal swabs from two adult males with acute rubella and products of conception from three women with serologically confirmed primary rubella in pregnancy. RV RNA was not detected in uninfected HEL and Vero cells or peripheral blood mononuclear cells. The results were concordant with those of an RT-PCR directed to the E1 protein coding region and with virus isolation. CONCLUSIONS: Detection of the non-structural coding region of the RV genome in clinical samples suggests that NS RT-PCR could be used as a confirmatory assay for prenatal diagnosis of congenital rubella, and that it will be of value for the identification of nucleotide changes in the 5' region of the RV genome.

Journal Article↗
PubMed2006

Vibrio parahaemolyticus in shellfish and clinical samples during two large epidemics of diarrhoea in southern Chile.

Large epidemics of diarrhoea associated with seafood consumption and Vibrio parahaemolyticus occurred during the austral summers of 2004 and 2005 in the environs of Puerto Montt, Chile (41 degrees 29'S 72 degrees 24'W). There are no reports of V. parahaemolyticus infections before 2004 in this region, their absence being explained by the low ocean temperatures which seldom reach 16 degrees C. We analysed V. parahaemolyticus obtained from shellfish and clinical samples during epidemics. Isolates were examined using conventional protocols and an improved method for restriction enzyme analysis using total bacterial DNA which permits direct genome restriction enzyme analysis by conventional gel electrophoresis (DGREA) with a similar discrimination index as restriction fragment length polymorphism-pulsed field gel electrophoresis (RFLP-PFGE). Analysis of clinical samples showed that the epidemics were caused by the V. parahaemolyticus O3:K6 pandemic clonal group. On the other hand, analysis of shellfish samples during both epidemics showed that 53% contained V. parahaemolyticus (3-93 g(-1)). Detailed analysis of 50 positive shellfish samples showed that only three contained detectable levels of the pandemic clone. Most V. parahaemolyticus isolates obtained from shellfish corresponded to non-pandemic clones differentiated into 14 groups by DGREA. In summary, the causative agent during epidemics was only a minor component of a small but diverse population of V. parahaemolyticus in shellfish.

Chile↗
PubMed1990

Rapid detection of herpes simplex virus in clinical samples by flow cytometry after amplification in tissue culture.

Murine monoclonal antibodies (MAbs) against herpes simplex virus type 1 and 2 (HSV-1 and -2, respectively) nuclear antigens were used to identify cells infected with HSV-1 or -2 by indirect immunofluorescence in conjunction with flow cytometry after virus amplification of MRC-5 cell monolayers. The results indicate that MAbs Q1, Q2, and H-640 detect HSV-1- and HSV-2-infected cells, MAb SD-1 detects HSV-2- but not HSV-1-infected cells, and MAb 58-S detects HSV-1- but not HSV-2-infected cells. MAb Q1, which detects HSV-1- as well as HSV-2-infected cells, was used to detect HSV-infected cells after inoculation and overnight (16- to 20-h) incubation of MRC-5 monolayers with clinical samples suspected of containing HSV. In comparing the efficiency of flow cytometry with cytopathic effect (CPE) in tissue culture for detecting HSV in clinical samples, HSV was detected by flow cytometry in 77% of the cases where HSV was detected by CPE in tissue culture. In many cases, flow cytometry detected HSV from 1 to 3 days before HSV was detected by CPE.

Antibodies, Monoclonal↗
PubMed2000

Simultaneous stereoselective analysis of venlafaxine and O-desmethylvenlafaxine enantiomers in clinical samples by capillary electrophoresis using charged cyclodextrins.

Capillary electrophoresis (CE) was used for the simultaneous chiral determination of venlafaxine (Vx), a new antidepressant drug and its main active metabolite. O-desmethyl venlafaxine (ODV). Among the charged cyclodextrins (CD) tested, phosphated gamma-CD was the most appropriate. Resolution of Vx and ODV was obtained with 50 mM phosphate buffer (pH 2.5) containing 20 mg/ml of phosphated gamma-CD. After optimisation of the method (including robustness), validation was carried out. Vx and ODV concentrations, as well as the enantiomeric ratio, were investigated in clinical samples. Chiral determination of Vx and ODV was performed after a simple liquid-liquid extraction (LLE). In the tested concentration range (25-500 ng/ml), coefficients of correlation were superior to 0.996. Within-day and between-day accuracy and precision were determined at three different concentrations for each enantiomer. Analyses of clinical samples (n = 16) exhibited non-racemic ratios for Vx and ODV, which suggests a stereoselective metabolism in humans.

Antidepressive Agents, Second-Generation↗
PubMed1997

Performance of the Composite International Diagnostic Interview Short Form for major depression in community and clinical samples.

The CIDI Short Form is a brief survey instrument designed to identify episodes of major depression. The instrument was developed for inclusion in the US National Health Interview Survey, but has also been used in the Canadian National Population Health Survey (NPHS). In this study, data deriving from use of the CIDI Short Form in the NPHS are compared to published data from the Mental Health Supplement of the Ontario Health Survey, which utilized a fully validated structured interview: the Composite International Diagnostic Interview (CIDI). In an additional analysis, the sensitivity and specificity of the Short Form were evaluated in relation to the full CIDI mood disorders section in a clinical sample of 122 psychiatric in-patients. Relative to published data from the Ontario Health Survey, application of the CIDI Short Form in the NPHS resulted in an overestimation of major depression prevalence by approximately 50%. In the clinical sample, the CIDI Short Form was highly sensitive (98.4%), but not highly specific (72.7%). Active medical conditions, substance use disorders and dysthymia were frequently observed among subjects with false positive CIDI Short Form ratings. The CIDI Short Form appears to overestimate the 12-month period prevalence of major depression when it is applied in community samples. Since the Short Form does not make exclusions for organically induced symptoms, it is probable that some subjects with depressive symptoms secondary to physical illnesses and/or drug exposures score above the instrument's threshold, perhaps leading to an elevation in period prevalence rates.

Adolescent↗
PubMed1999

Diagnosis of foot-and-mouth disease by RT-PCR: evaluation of primers for serotypic characterisation of viral RNA in clinical samples.

Multiple primers designed from the 1D and 2AB regions of the foot-and-mouth disease (FMD) viral genome were evaluated extensively for the detection of all seven serotypes of the virus by reverse transcription polymerase chain reaction (RT-PCR) at the OIE/FAO World Reference Laboratory for FMD (WRL), Pirbright. The primers had been characterised previously elsewhere on a relatively small number of cell culture grown isolates and epithelial suspensions and had been shown to identify and differentiate all seven serotypes of FMD virus. The extended study evaluated several RT-PCR protocols on epithelial suspensions and supernatant fluids, resulting from their passage in cell culture, derived from clinical samples of diverse molecular characteristics. Each of the serotype-specific primers in selected RT-PCR protocols demonstrated suitable specificity and detected cell culture passaged isolates with some success but were not adequate for the serotyping of suspensions prepared from clinical samples of epithelium. The results showed that the primers can be used in RT-PCR procedures in conjunction with the routine detection methods of virus isolation and ELISA for the diagnosis and serotyping of FMD virus.

Animals↗
PubMed2003

Nucleotide sequence-based typing of meningococci directly from clinical samples.

The unpredictable characteristics of meningococcal disease (MD) make outbreaks complicated to monitor and consequently lead to high levels of public anxiety. Traditional molecular techniques have been utilized in order to understand better the epidemiology of MD, but some have disadvantages such as being highly specialized and labour-intensive, with low reproducibility. Some of these problems have been overcome by using multilocus sequence typing (MLST). This technique exploits the unambiguous nature and electronic portability of nucleotide sequencing data for the characterization of micro-organisms. The need for enhanced surveillance of MD after the introduction of serogroup C conjugate vaccines means that it is important to gain typing information from the infecting organism in the absence of a culture isolate. Here, the application of MLST for the laboratory confirmation and characterization of Neisseria meningitidis directly from clinical samples is described. This involved using a newly designed set of primers that were complementary to nucleotide sequences external to the existing MLST primers already in use for culture-based MLST of meningococci. This combination has produced a highly sensitive procedure to allow the efficient genotypic characterization of meningococci directly from clinical samples.

DNA Primers↗
PubMed1993

Detection of foot-and-mouth disease virus RNA in clinical samples and cell culture isolates by amplification of the capsid coding region.

Foot-and-mouth disease is one of the most economically important virus diseases of livestock. Two important requirements for the control of this disease are rapid laboratory diagnosis and epidemiological investigation. The use of the polymerase chain reaction method (PCR) to amplify specific nucleic acid regions offers the unique possibility of combining swift viral detection with the production of genetic material suitable for sequencing and other methods of molecular epidemiological analysis. The sequencing of the region of foot-and-mouth disease virus (FMDV) genome encoding the capsid proteins of the virus (approximately 2260 bps), provides valuable information that adds to the molecular characterisation of an isolate. This paper describes the use of the PCR for the amplification of this region of the FMDV genome from bovine clinical samples and cell culture isolates. Suitable pairs of oligonucleotide primers were selected from the published sequence of FMDV type O1, Kaufbeuren. One primer set amplified 2091 bps of the capsid coding region of all seven serotypes of FMDV. The other primer set amplified 216 bp from this region of FMDV type O1, BFS 1860, in nucleic acid extracts from several clinical samples. Nucleic acid extracts from the picornaviruses, bovine enterovirus and swine vesicular disease virus, which affect the same animals, were not amplified. Direct sequencing was carried out on the amplified fragments and showed that the PCR products were > 98% homologous to published FMDV sequences.

Animals↗
PubMed2002

The role of stress in the onset of depressive disorders. A controlled study in a Spanish clinical sample.

BACKGROUND: We conducted the present study to evaluate the impact of stressful events on the onset of depressive disorders in a Spanish clinical sample, compared to a control group matched for age, sex, civil status and social class. We compared our results with those of other studies carried out with samples that were both clinically and culturally similar to ours. METHOD: Fifty depressed patients that were diagnosed with a depressive episode in the 6 months prior to the interview and 50 healthy controls were included in the study. Both groups were compared on the "Life Events and Difficulties Schedule" (LEDS). RESULTS: Of the depressive patients, 68 % compared to only 18 % of the control individuals experienced at least one provoking agent in the 12 months prior to the onset of the symptoms. The risk of developing a depressive disorder was 9.7 % greater in subjects exposed to such provoking agents. Chronic difficulties are equally important to the genesis of depressive disorders as severe life events. No significant differences were seen between the two diagnostic subgroups of depressed patients in the accumulation of severe events, major difficulties or provoking agents. CONCLUSION: The results support the view that stress is a major factor in the aetiology of depressive disorders. The amount of stress suffered by the patients, however, was less than that found in our healthy sample. Important issues about the model of interaction between stress and depression are discussed.

Adolescent↗
PubMed2003

Detection of Neisseria Meningitidis in clinical samples by a duplex real-time PCR targeting the porA and ctrA genes.

BACKGROUND: In recent years PCR has proven to be a highly sensitive and specific method for the diagnosis of infections caused by Neisseria meningitidis. STUDY DESIGN: We developed and evaluated a N. meningitidis LightCycler real-time duplex PCR (NM-LCdPCR) capable of simultaneously detecting and distinguishing between two separate genes on the N. meningitidis genome. METHODS: The NM-LCdPCR was developed on the LightCycler platform (Roche Diagnostics, Castle Hill, NSW, Australia) and comprised two primer pairs and two hybridization probe sets, enabling the detection of both the porA and ctrA genes within the same reaction mix. To distinguish between the fluorescence emitted by each hybridization probe set, each downstream probe was labeled with a different fluorophore (either LC-Red640 or LC-Red705). The results obtained by the NM-LCdPCR were then compared with the results obtained by a mono-specific LightCycler assay targeting the porA gene only (porA-LCPCR). PATIENTS: One-hundred and forty-eight clinical samples from patients with suspected meningococcal infection were evaluated. RESULTS: The results of the NM-LCdPCR and porA-LCPCR gave 100% agreement; N. meningitidis DNA was detected in 25 samples whereas 123 samples were negative by both assays. The breakdown of the NM-LCdPCR results show that both genes were detected in 26 of the 28 positive samples. DISCUSSION: By targeting two separate N. meningitidis genes, the NM-LCdPCR has the potential to prevent the false-positive results which may arise from sequence variation. In addition, the ability to detect and discriminate between the two different N. meningitidis genes within the same reaction mix offers a rapid means for confirming the presence of N. meningitidis DNA in clinical samples, thereby reducing the need for subsequent confirmatory assays to be performed. CONCLUSIONS: The sensitivity and specificity of the NM-LCdPCR assay, combined with its ability to detect and discriminate both the N. meningitidis porA and ctrA genes, make it suitable for the diagnosis of N. meningitidis infections in the routine clinical laboratory.

Bacterial Proteins↗