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Negative PCR (negative + pcr)
Selected AbstractsParental conditional regard as a predictor of deficiencies in young children's capacities to respond to sad feelingsINFANT AND CHILD DEVELOPMENT, Issue 5 2010Guy Roth Abstract This study explored the relationship between parents' use of conditional regard (PCR, Assor, Roth, & Deci, 2004; Roth, 2008) to promote suppression of sad feelings and the following emotional skills in young children: (1) recognition of sadness in facial expressions, (2) awareness of sad feelings in oneself, and (3) empathic response to others' sad feelings. The study distinguished between two PCR components: conditional negative regard (similar to love withdrawal) and conditional positive regard. Emotion-focused interviews were conducted with 102 children aged 5,6 years, and their parents completed questionnaires assessing parents' use of conditional regard. As expected, both PCR components correlated negatively with the emotional skills. Regression analyses showed that the seemingly benign practice of conditional positive regard had unique negative associations with the three emotional skills also when effects of negative PCR were controlled. Copyright © 2010 John Wiley & Sons, Ltd. [source] Simultaneous PCR Detection of the Two Major Bacterial Pathogens of GeraniumJOURNAL OF PHYTOPATHOLOGY, Issue 2 2002D. L. GLICK Xanthomonas campestris pv. pelargonii (Xcp) and Ralstonia solanacearum (Rs) are the two most important bacterial pathogens of commercially cultivated geraniums (Pelargonium spp.), both causing bacterial wilt and leaf spot. Asymptomatic infections are important reservoirs of infections in commercial growing facilities. Our objective was to design a multiplex PCR (Polymerase Chain Reaction) assay to detect infection by either or both of these pathogens. We used a previously characterized PCR primer pair for Xcp that amplifies a region of 200 bp. In addition, we designed a new primer pair specific for Rs that amplifies a region of 822 bp. With these two primer pairs, we could detect either or both pathogens. As geranium tissue extracts frequently contain inhibitors of the PCR process, a negative PCR could result from either an accurate indication that the plant was pathogen-free or from a false negative assay. We therefore designed `amplification competence' primers, targeting a portion of the geranium 18 s rRNA gene, and generating a 494-bp amplification product that confirms amplification competence and validates a negative assay result. Thus, the triple primer pair multiplex PCR screens for the two most important bacterial pathogens of geraniums simultaneously confirms amplification competence for each geranium sample. [source] Usefulness of PCR Strategies For Early Diagnosis of Chagas' Disease Reactivation and Treatment Follow-Up in Heart TransplantationAMERICAN JOURNAL OF TRANSPLANTATION, Issue 6 2007M. Diez Heart transplantation (HTx) is a useful therapy for end-stage Chaga, cardiomyopathy; however, Chagas reactivation remains a mayor complication. Parasitological methods offer poor diagnostic sensitivity, and use of more sensitive tools such as the Polymerase chain reaction (PCR) is usually necessary. In the present study, reactivation incidence and PCR usefulness for early reactivation diagnosis, as well as for treatment response evaluation during follow-up, were analyzed using Strout parasite detection test, in 10 of 222 consecutive HTx patients suffering Chagas cardiomyopathy. PCR strategies targeted to minicircle sequences (kDNA, detection limit 1 parasite/ 10 mL blood) and miniexon genes (SL-DNA, 200 parasite/10 mL) were performed to compare parasite burdens between samples. No patients received prophylactic antiprotozoal therapy (benznidazole). Five patients (50%) exhibited clinical reactivation within a mean period of 71.6 days; positive Strout results were observed in most cases presenting clinical manifestations. kDNA-PCR was positive 38,85 days before reactivation, whereas SLDNA-PCR became positive only 7,21 days later, revealing post-HTx parasitic load enhancement present prior to clinical reactivation development. Reactivations were successfully treated with benznidazole and generated negative PCR results. Results observed in this study indicate the value of PCR testing for an early diagnosis of Chagas reactivation as well as for monitoring treatment efficacy. [source] Prediction of congenital toxoplasmosis by polymerase chain reaction analysis of amniotic fluidBJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 5 2005L. Thalib Objective To determine the accuracy of polymerase chain reaction (PCR) analysis of amniotic fluid for fetal toxoplasmosis according to clinical predictors of outcome and study centre. Design Prospective cohort study. Setting Nine European centres. Population Women with suspected toxoplasma infection identified by prenatal screening. Methods Logistic regression was used to examine the effects of gestational age at maternal seroconversion, treatment and timing of amniocentesis, on PCR accuracy, and to calculate the post-test probability of congenital toxoplasmosis. Main outcome measures Infants had congenital toxoplasmosis if specific IgG persisted beyond 11.5 months. Uninfected infants had undetectable IgG in the absence of anti-toxoplasma treatment. Results Of 593 PCR results, 64 were positive (57 confirmed infected), and 529 were negative (23 confirmed infected). The likelihood ratio for a positive PCR result decreased significantly with trimester at seroconversion, but did not change significantly for a negative result. Weak associations were detected between sensitivity and, inversely, with specificity, and gestational age at maternal seroconversion. There was no significant association between sensitivity and centre, type or duration of treatment, or timing of amniocentesis. Specificity differed significantly between centres (P < 0.001). The change in pre- to post-test probability of infection was maximal for a positive PCR after first trimester seroconversion, affecting 1% of women tested, and a negative PCR after third trimester seroconversion, affecting half the women tested. Conclusions Prediction of the risk of congenital toxoplasmosis should combine estimates of test accuracy and maternal,fetal transmission, which take account of the gestational age at which the mother seroconverted. Local laboratory standards will affect the generalisability of these results. [source] Herpes simplex virus type 1 encephalitis associated with acute retinal necrosis syndrome in an immunocompetent patientACTA OPHTHALMOLOGICA, Issue 5 2002Philippe Gain ABSTRACT. Purpose:, The onset of acute retinal necrosis secondary to herpes simplex encephalitis is exceptional. We report such an association in an immunocompetent patient, in whom the genome of herpes simplex virus type 1 (HSV-1) was identified successively at both sites of infection. Methods:, Polymerase chain reaction (PCR) assay of HSV-1 in cerebrospinal fluid (CSF) and aqueous humour. Results:, An immunocompetent patient aged 40 years presented with HSV-1 encephalitis, which was confirmed by imaging, viral serology and identification of the HSV-1 genome in the CSF. The subject's immunological profile was normal. The patient was treated with foscavir. Six weeks after clinical recovery and negative PCR, the patient presented with a unilateral acute retinal necrosis syndrome. Polymerase chain reaction of the aqueous humour was positive, while serology and PCR of the CSF remained negative. Conclusion:, Identification of the HSV-1 genome at the two successive sites of infection stresses the possibility of brain-to-eye transmission of HSV-1. [source] | ||||||||||