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'RETCIF': a rapid, sensitive method for detection of viruses, applicable for large numbers of clinical samples.

Rapid detection of viruses in clinical samples is important for continuing appropriate antiviral treatment and discontinuing unnecessary antibacterial treatment, as well as for excluding viral pathogens. Yet detection of viral agents may require numerous susceptible cell lines. Even with the shell vial culture method, it is cumbersome for handling large volumes of specimens. A procedure has been developed, which is time and cost-saving and uses specific cell lines in a 96-well microtitre plate and monoclonal antibodies (RETCIF-rapid enhanced tissue culture immunofluorescence). Each clinical sample was inoculated into 12 different wells with five different cell lines. Enhancement was achieved by sonication, centrifugation and hormonal supplementation to the medium used. Cytomegalovirus (CMV), herpes simplex virus (HSV) and respiratory viruses were detected by monoclonal antibodies on day 2, whilst varicella zoster virus (VZV) and enteroviruses were detected on days 5 and 7, respectively. During July-December 1998, 3298 patient specimens were compared by RETCIF and a modified shell vial method. Either or both methods isolated 779 viruses (24% positivity rate), whilst both methods detected 621. Of the 779 viruses, 87% (679) were isolated by the shell vial method in an average time of 4.9 days. For RETCIF the respective rate was 92.5% (721), in an average time of 3.0 days. The RETCIF method is a time-saving procedure, with higher isolation rates than the shell vial method.

Antibodies, Monoclonal↗

[Evaluation of different clinical samples and cell lines in the isolation of enterovirus in pediatric patients].

BACKGROUND: To evaluate prospectively the efficacy of different clinical samples and cellular lines in the isolation of Enteroviruses from pediatric patients. METHODS: In the period july-1997 to july-1999 we analyze the samples of 102 pediatric patients (< 2 years old) with an unknown febrile etiology syndrome. After the process of decontamination the samples were inoculated in the MRC-5, Hep-2 and Vero cell lines by the shell-vial assay. After 2-3 days of incubation the monolayers were stained by a monoclonal antibody against VP1; then the strains were identified as Poliovirus, ECHO-virus or Coxsacke by specific antibodies. RESULTS: 96 clinical samples were studied (45 pharyngeal swabs, 28 feces, 13 cerebrospinal fluid, 5 bloods, 4 urines and one bronchoalveolar lavage). Enteroviruses were isolated in 48 patients (47%), corresponding to 60 clinical samples (62.5%). The enteroviruses were isolated in 75.5% of pharyngeal swabs, 71.4% of feces, 30.7% of cerebrospinal fluid, one blood (20%) and the bronchoalveolar lavage. 28 patients presented simultaneously both pharyngeal and rectal swabs; in this group the use of both samples permitted the isolation of Enteroviruses in 26 cases (92.8%). Of 60 Enteroviruses, 59 (98.3%) were isolated in the MRC-5 cell line, 23 (38.3%) in the Hep-2, and 14 (23.3%) in the Vero; the MRC-5 demonstrated a significant difference in the isolation of Enteroviruses compared with the other cell lines. The Enteroviruses were identified as 30 (50%) ECHO-virus, 15 (25%) as Poliovirus vaccine, 12 (20%) could not to be identified and in 3 cases (5%) no growth of virus was detected in the culture. The MRC-5 cell line was significatively superior to the other in the isolation of the different Enteroviruses. CONCLUSIONS: To obtain the maximum diagnostic efficacy in front a patient with a possible infection by Enteroviruses, is necessary to use different clinical samples, specially the more related to the infection focci (cerebrospinal fluid or blood). The MRC-5 cell line has been the most efficace in the isolation of Enteroviruses independently of the type of clinical sample or the viral genus. The shell-vial assay is a good method for the isolation and identification of Enteroviruses isolated from clinical samples.

Animals↗

The relative effects of maternal and child problems on the quality of attachment: a meta-analysis of attachment in clinical samples.

In this meta-analysis of 34 clinical studies on attachment the hypothesis is tested that maternal problems such as mental illness lead to more deviating attachment classification distributions than child problems such as deafness. A correspondence analysis on 21 North American studies with normal subjects produced a baseline against which the clinical samples could be evaluated. Separate analyses were carried out on studies containing the traditional A, B, C classifications and on studies that also included the recently discovered D or A/C category. Results show that groups with a primary identification of maternal problems show attachment classification distributions highly divergent from the normal distributions, whereas groups with a primary identification of child problems show distributions that are similar to the distributions of normal samples. The introduction of the D or A/C classifications (about 15% in normal samples) reveals an overrepresentation of D or A/C in the child problem groups, but the resulting distribution still is much closer to the normal distributions compared to the samples with maternal problems. In clinical samples, the mother appears to play a more important role than the child in shaping the quality of the infant-mother attachment relationship.

Child Behavior Disorders↗

The development of the MMPI-A Immaturity Scale: findings for normal and clinical samples.

The Immaturity (IMM) Scale was developed as a supplementary scale for the Minnesota Multiphasic Personality Inventory-Adolescent (MMPI-A). This study describes the development of the IMM Scale and presents some concurrent validity data derived from the MMPI-A normative sample of 1,620 adolescents and a clinical sample of 122 adolescent inpatients. The IMM Scale was examined in relation to Biographical and Life Events data to identify external correlates for the MMPI-A normative sample. In the clinical sample, external correlates were derived from diagnostic and rating form data provided by the adolescents' treatment staff and by their parents. Current findings were discussed in terms of the relationship of correlate patterns to descriptions of the preconformist and conformist stages of Loevinger's (1976) concept of ego development, and future research directions were suggested.

Adolescent↗

Dysexecutive symptoms among a non-clinical sample: a study with the use of the Dysexecutive Questionnaire.

Clinical studies indicate that damage to the frontal lobes may lead to a set of symptoms collectively known as 'Dysexecutive syndrome', which is characterized by changes in emotion, personality, motivation, behaviour and cognitive aspects. Factor analytical study using questionnaires measuring dysexecutive problems in everyday life also suggests a fractionation of the dysexecutive syndrome among patients with neurological disorders. As yet, very little research has been conducted to explore the base-rate of executive problems in everyday life among the non-clinical population. This pilot study aimed to explore dysexecutive behaviour similar to that of dysexecutive syndrome reported by a non-clinical sample. A total of 93 presumably normal participants were recruited. The Dysexecutive Questionnaire and a set of clinical tests of executive function were administered to all the participants. A 5-factor solution very similar to that of a previous study was derived: inhibition (factor 1), intentionality (factor 2), knowing-doing dissociation (factor 3), in-resistance (factor 4), and social regulation (factor 5). Correlation was established among the derived factors and tests of executive function. This study provides empirical evidence that a non-clinical sample may encounter similar dysexecutive behaviours in daily life. The issue of the fractionation of the executive system among the non-clinical sample will also be discussed.

Adult↗

Dysexecutive symptoms among a non-clinical sample: A study with the use of the Dysexecutive Questionnaire.

Clinical studies indicate that damage to the frontal lobes may lead to a set of symptoms collectively known as 'Dysexecutive syndrome', which is characterized by changes in emotion, personality, motivation, behaviour and cognitive aspects. Factor analytical study using questionnaires measuring dysexecutive problems in everyday life also suggests a fractionation of the dysexecutive syndrome among patients with neurological disorders. As yet, very little research has been conducted to explore the base-rate of executive problems in everyday life among the non-clinical population. This pilot study aimed to explore dysexecutive behaviour similar to that of dysexecutive syndrome reported by a non-clinical sample. A total of 93 presumably normal participants were recruited. The Dysexecutive Questionnaire and a set of clinical tests of executive function were administered to all the participants. A 5-factor solution very similar to that of a previous study was derived: inhibition (factor 1), intentionality (factor 2), knowing-doing dissociation (factor 3), in-resistance (factor 4), and social regulation (factor 5). Correlation was established among the derived factors and tests of executive function. This study provides empirical evidence that a non-clinical sample may encounter similar dysexecutive behaviours in daily life. The issue of the fractionation of the executive system among the non-clinical sample will also be discussed.

Journal Article↗

Rapid detection of Mycoplasma pneumoniae in clinical samples by the polymerase chain reaction.

A DNA amplification method was used to detect Mycoplasma pneumoniae in clinical samples. M. pneumoniae 16S ribosomal RNA gene sequences were selected as the amplification target region. The polymerase chain reaction (PCR) with purified DNA fragments as templates yielded an expected 88-bp fragment from M. pneumoniae but not from other Mycoplasma spp. nor from any of the other bacteria assayed. With this method, the 88-bp product specific for M. pneumoniae could be obtained from a minimum of 0.05 pg of M. pneumoniae DNA. Subsequently this PCR technique was used for the detection of M. pneumoniae in throat-swab samples. Twenty-two of 30 culture-positive clinical samples gave positive results in the PCR test. Thirty-two culture-negative clinical samples and 33 samples from healthy volunteers, of which only one was culture-positive, gave negative results in the same PCR test. This PCR method is useful for the direct detection of M. pneumoniae in clinical samples.

Base Sequence↗

Differentiation of herpes simplex virus types 1 and 2 in clinical samples by a real-time taqman PCR assay.

While the clinical manifestations of HSV-1 and -2 overlap, the site of CNS infection, complications, response to antivirals, frequency of antiviral resistance, and reactivation rate on mucosal surfaces varies between HSV-1 and -2. Detection of HSV DNA by PCR has been shown to be the most sensitive method for detecting HSV in clinical samples. As such, we developed a PCR-based assay to accurately distinguish HSV-1 from HSV-2. Our initial studies indicated the assay using type specific primers was slightly less efficient for detecting HSV-1 and -2 DNA than the high throughput quantitative PCR assay we utilize that employs type common primers to gB. We subsequently evaluated the type specific assay on 3,131 specimens that had HSV DNA detected in the type common PCR assay. The typing results of these specimens were compared with the monoclonal antibody staining results of culture isolates collected from the same patients at the same time, and the HSV serologic status of the patient. The typing assay accurately identified both HSV-1 and -2 with a specificity of >99.5% and was significantly more sensitive than typing by culture and subsequent monoclonal antibody assays. Complete concordance was seen between the typing assay and HSV serologic status of the patient. Dual (HSV-1 and -2) infection in clinical samples was recognized in 2.6% of clinical samples using the new typing assay. This assay, when used in combination with the type common assay, can now accurately type almost all mucosal and visceral HSV isolates by molecular techniques.

Antibodies, Monoclonal↗

Alcohol relapse as a function of relapse definition in a clinical sample of adolescents.

Relapse is an important clinical and research problem in the addictions, but one that has no consensus on an operational definition. How relapse is measured could make substantial differences in clinical practice and in conclusions drawn from empirical studies. The aim of this study was to compare and contrast four different operational definitions of alcohol relapse in a clinical sample of adolescents. The participants were 75 males and females ages 14-18 who presented for outpatient treatment of alcohol use disorder (AUD). They completed an extensive in-person initial assessment, as well as 12 subsequent monthly telephone interviews that concerned their daily alcohol and other drug use and related events. The four alcohol relapse definitions evaluated included: at least 1 day of drinking any amount after at least 4 consecutive days of abstinence; at least 1 heavy (five standard drinks for boys, four for girls) drinking day after 4 abstinent days; at least 1 day of drinking any amount with associated problems after 4 abstinent days; and at least 1 heavy drinking day with associated problems following 4 abstinent days. Relapse events were identified during the first 6 months following the initial interview. The results showed that the time period until relapse varied across the four definitions of relapse ranging from 26 to 90 days. Additional analyses investigated the utility of each of the definitions in predicting functioning during months 7-12 using multiple regression. The results of these analyses showed that the two "heavy drinking" definitions contributed significantly independent variance to predicting average number of drinking days/month and drinks/drinking day and that the two "any drinking" definitions significantly predicted the presence of a current AUD diagnosis. The results suggest that relapse definitions make a difference in estimates of rates and times to first relapse. Furthermore, the occurrence of at least one relapse is predictive of later functioning in a clinical sample of adolescents, which is of practical and theoretical importance. Suggestions for the extensions of this investigation in future research are provided.

Adolescent↗

Exploratory factor analysis of two measures of posttraumatic stress disorder (PTSD) symptoms in a non-clinical sample of college students.

This study investigated the psychometric structure of two widely utilized measures of posttraumatic symptoms in a primarily Caucasian non-clinical sample. Given the prevalence of trauma exposure in non-referred samples, measurement of resulting symptoms is a critical issue. Exploratory factor analysis was utilized to assess and compare the factor structure of the Impact of Event Scale [IES; Horowitz, M., Wilner, N., & Alvarez, W. (1979). Impact of Event Scale: a measure of subjective stress. Psychosomatic Medicine, 41, 209-218] and the Mississippi Scale for Posttraumatic Stress Disorder, Civilian version [MIS-Civ; Vreven, D. L., Gudanowski, D. M., King, L. A., & King, D. W. (1995). The Civilian Version of the Mississippi PTSD Scale-a psychometric evaluation. Journal of Traumatic Stress, 8, 91-109] in a sample of college students reporting exposure to potentially traumatic events. The psychometric structure of the IES was largely consistent with the two-factor structure widely reported in the literature, while the structure of the MIS-Civ varied considerably in this sample. Notably, non-clinical samples tended to report fewer social and occupational dysfunction than clinical samples predominantly utilized in PTSD research. Implications for use of these instruments in screening samples are discussed.

Adult↗

Factor structure of the Wechsler Adult Intelligence Scale-revised (WAIS-R): a clinical sample.

Factor analysis was performed on a heterogeneous clinical sample of neurological patients. Both a two- and a three-factor model were extracted. The two-factor solution corresponded to Wechsler's categorization of verbal and performance subtests. The three-factor solution suggested a verbal comprehension factor, a perceptual organization and a third factor with highest loadings on digit span, arithmetic and digit symbol. Both models were consistent with factor models obtained from the standardization sample. As has previously been reported in neurologically impaired samples, the third factor was relatively more prominent than in the standardization sample. This study provides further evidence for the robustness of the WAIS-R factor structure across different populations and gives good support for the use of the WAIS-R in British clinical samples.

Adult↗

Genotyping of pathogenic Acanthamoebae isolated from clinical samples in Greece--report of a clinical isolate presenting T5 genotype.

Amoebae belonging to the genus Acanthamoeba are potentially pathogenic to humans, causing mainly amoebic keratitis. Pathogenic ability of the 15 known Acanthamoeba genotypes is under investigation. We report that four out of five cases of amoebic keratitis studied in Greece, present T4 sequence type, while the remaining one presents T5 sequence type (Acanthamoeba lenticulata), which is the second most frequent genotype found among environmental samples. Thus, it is confirmed, for the first time to our knowledge, that A. lenticulata can cause keratitis. However the reason that it is under represented in clinical samples compared to environmental ones is unknown.

Acanthamoeba↗

Distinct cross-resistance profiles of the new protease inhibitors amprenavir, lopinavir, and atazanavir in a panel of clinical samples.

A panel of 245 clinical samples with known treatment histories was retrospectively evaluated for cross-resistance to new protease inhibitors (PI). Samples with resistance to previously approved PI displayed high cross-resistance to atazanavir, whereas cross-resistance to amprenavir was considerably lower. A similar cross-resistance profile was observed for lopinavir, if a higher cut-off for resistance (9.5-fold) was applied. The enhanced efficacy of boosted PI is discussed with respect to clinically relevant cut-offs for drug resistance.

Atazanavir Sulfate↗

Use of broth enrichment and real-time PCR to exclude the presence of methicillin-resistant Staphylococcus aureus in clinical samples: a sensitive screening approach.

A rapid and sensitive method for excluding the presence of methicillin-resistant Staphylococcus aureus (MRSA) in clinical samples was developed and evaluated. The method utilised an MRSA-selective enrichment broth for 16 h, followed by PCR quantification of the nuc gene. Samples below a quantitative PCR threshold were reported as MRSA-negative. Broths from PCR-positive samples were subcultured for MRSA isolation. Clinical samples (n = 334) in a constructed high prevalence population were analysed in parallel with a selective plating method. The new broth-PCR assay increased the number of positive samples by 35% (49 vs. 66), and 94% of negative samples were reported within 24 h. To reduce costs and workload, 665 clinical samples were grown separately in enrichment broth and then pooled in the PCR step. The broth-PCR assay increased the number of MRSA positive samples from 11 to 15 compared with selective plating. Most (89%) of the culture-negative samples were also PCR-negative and could be reported within 24 h. The growth of 25 European EMRSA strains was tested in the selective enrichment broth. On average, the MRSA strains showed a 300 000-fold increase in CFU, compared with 30-fold for the eight methicillin-sensitive Staphylococcus aureus strains tested.

Bacterial Proteins↗

Validation of a new scoring system for the Weigl Color Form Sorting Test in a memory disorders clinic sample.

The Bristol Memory Disorders Clinic uses the Weigl Color Form Sorting Test (CFST) to appraise abstraction and the ability to shift set. The original scoring system for the CFST (Grewal & Haward, 1984), developed on the premise that sorting to form is more difficult than sorting to color, had no score for an individual able to sort to form and subsequently unable to shift to color with a cue. Clinical experience suggested that the performance of some individuals required such a score. A new scoring system was developed and validated in a memory-disorders-clinic sample. The validation showed the new score to be necessary and gave support to the original premise that people with organic brain damage show a preference for sorting to color.

Aged↗

Measurement of aluminium in clinical samples.

Measurement of aluminium in clinical samples is important for the protection of patients with chronic renal failure, and for investigations of dementia. The types of specimen that need to be analysed include body fluids and tissues, dialysis fluids, water and foods and the concentrations that may be found can range from around 1 microgram/L to several mg/L. Although techniques must afford exceptional sensitivity they will also be susceptible to the effects of external contamination and it is imperative that those involved with the analysis, from sample collection through to the determination, ensure that precautions are taken to prevent undue addition of the metal. Of the methods that may be used ETAAS is clearly the most appropriate. Great care is required to achieve reliable performance but with experienced personnel very good results can be obtained. Regular reviews of recent analytical developments are presented in the Atomic Spectrometry Updates series and these are recommended to those who may wish to look for further information.

Aluminum↗

Gene expression profiling reveals consistent differences between clinical samples of human leukaemias and their model cell lines.

Microarray gene expression profiles of fresh clinical samples of chronic myeloid leukaemia in chronic phase, acute promyelocytic leukaemia and acute monocytic leukaemia were compared with profiles from cell lines representing the corresponding types of leukaemia (K562, NB4, HL60). In a hierarchical clustering analysis, all clinical samples clustered separately from the cell lines, regardless of leukaemic subtype. Gene ontology analysis showed that cell lines chiefly overexpressed genes related to macromolecular metabolism, whereas in clinical samples genes related to the immune response were abundantly expressed. These findings must be taken into consideration when conclusions from cell line-based studies are extrapolated to patients.

Gene Expression↗

The use of proteomics for the assessment of clinical samples in research.

Proteomics, the analysis of expressed proteins, has been an important developing area of research for the past two decades [Anderson, NG, Anderson, NL. Twenty years of two-dimensional electrophoresis: past, present and future. Electrophoresis 1996;17:443-453]. Advances in technology have led to a rapid increase in applications to a wide range of samples; from initial experiments using cell lines, more complex tissues and biological fluids are now being assessed to establish changes in protein expression. A primary aim of clinical proteomics is the identification of biomarkers for diagnosis and therapeutic intervention of disease, by comparing the proteomic profiles of control and disease, and differing physiological states. This expansion into clinical samples has not been without difficulties owing to the complexity and dynamic range in plasma and human tissues including tissue biopsies. The most widely used techniques for analysis of clinical samples are surface-enhanced laser desorption/ionisation mass spectrometry (SELDI-MS) and 2-dimensional gel electrophoresis (2-DE) coupled to matrix-assisted laser desorption ionisation [Person, MD, Monks, TJ, Lau, SS. An integrated approach to identifying chemically induced posttranslational modifications using comparative MALDI-MS and targeted HPLC-ESI-MS/MS. Chem. Res. Toxicol. 2003;16:598-608]-mass spectroscopy (MALDI-MS). This review aims to summarise the findings of studies that have used proteomic research methods to analyse samples from clinical studies and to assess the impact that proteomic techniques have had in assessing clinical samples.

Biomarkers↗