Setting out the frame conditions for feasible use of FFPE derived RNA

Introduction

The usage of formalin-fixed paraffin embedded (FFPE) tissue is characterized by its long shelf-life and simple handling. Therefore it is the most commonly available tissue specimen in routine diagnostics and histological studies. Formaldehyde fixation may result in RNA degradation and cross linking with proteins, while storage conditions also affect RNA integrity. The present study was designed to investigate the influence of these factors on RNA analysis.

Prevotella bivia as an unusual cause of endocarditis

A case of monomicrobial endocarditis due toPrevotella bivia in a 60-year-old man without previous cardiac lesions is reported. The extremely indolent course with multiple systemic emboli as the only clinical manifestation occurring at least seven months before diagnosis and the persistently negative blood cultures were remarkable features of this case. The incidence, clinical characteristics, treatment and outcome of published cases of infective endocarditis due to anaerobic bacteria are briefly reviewed.     

doublecortin is the major gene causing X-linked subcortical laminar heterotopia (SCLH)

Subcortical laminar heterotopia (SCLH), or 'double cortex', is a cortical dysgenesis disorder associated with a defect in neuronal migration. Clinical manifestations are epilepsy and mental retardation. This disorder, which mainly affects females, can be inherited in a single pedigree with lissencephaly, a more severe disease which affects the male individuals. This clinical entity has been described as X- SCLH/LIS syndrome. Recently we have demonstrated that the doublecortin gene, which is localized on the X chromosome, is implicated in this disorder. We have now performed a systematic mutation analysis of doublecortin in 11 unrelated females with SCLH (one familial and 10 sporadic cases) and have identified mutations in 10/11 cases. The sequence differences include nonsense, splice site and missense mutations and these were found throughout the gene. These results provide strong evidence that loss of function of doublecortin is the major cause of SCLH. The absence of phenotype-genotype correlations suggests that X-inactivation patterns of neuronal precursor cells are likely to contribute to the variable clinical severity of this disorder in females.      

Association of respiratory picornaviruses with acute bronchiolitis in French infants.

BACKGROUND: Human rhinoviruses and enteroviruses (Picornaviridae) are suspected to be major viral etiological causes of bronchiolitis in infants. OBJECTIVES: In the present study, we assessed the potential role of the respiratory picornaviruses as causative agents of bronchiolitis in French infants. STUDY DESIGN: From September 2001 to June 2002, we prospectively selected 192 infants < or =36 months of age and hospitalized for acute bronchiolitis. The detection of common respiratory viruses (respiratory syncytial virus, influenza virus A and B, parainfluenza virus 1, 2, 3 and adenovirus) was performed using classical immunofluorescence antigen and cell-culture detection assays on nasopharyngeal aspirates whereas the detection of human metapneumovirus (HMPV) was performed by a real-time RT-PCR assay. The presence of rhinovirus and/or enterovirus was assessed in respiratory samples by a picornavirus RT-PCR detection assay followed by a differential Southern blotting procedure. RESULTS: A potential causative virus was detected in 72.5% of the 192 study infants. RSV (30%), rhinovirus (21%), enterovirus (9%), influenza virus A (6%) and human metapneumovirus (4%) were the most frequent causative agents detected. Rhinoviruses or enteroviruses were detected as the only evidence of respiratory viral tract infection in 57 (30%) of 192 infants, whereas rhinovirus or enterovirus occurred in mixed viral infection detected in 25 (13%) of 192 study cases (30% versus 13%, p<10(-3)). CONCLUSIONS: Our data suggest that respiratory picornaviruses are one of the leading etiological causes of bronchiolitis in French infants. These findings highlight the need to implement a rapid picornavirus RT-PCR detection assay for the clinical diagnosis of respiratory infections in pediatric patients with bronchiolitis.     

Benign epileptic infantile spasms

Among 100 infants with infantile spasms studied before treatment, 14 had idiopathic spasms with a favourable outcome. They had a normal development, including reaching for objects before the age of 5 months and moderate regression without loss of eye following. Although it was hysarhythmic, the EEG tracing showed identifiable basic activity and sleep spindles; there was no slow waves focus even after diazepam administration and the spasms were "independent" even during a cluster. This type of infantile spasms seems to be a particular type of non-lesional epilepsy. It contrasts with idiopathic spasms of unfavourable outcome that apparently result from a preexisting and overlooked focal lesion responsible of later cognitive troubles.     

Detection of Trichomonas vaginalis using the polymerase chain reaction in pregnant and non-pregnant women

Objective:Trichomonas vaginalis vaginal infections are often both asymptomatic and difficult to detect by current methods. We evaluated the ability of a newly developed polymerase chain reaction (PCR) assay to identify T. vaginalis in vaginal samples from pregnant and non-pregnant women.Methods: In the 1st study, we compared the prevalence of T. vaginalis detection by PCR and culture using Diamond's medium in 52 women with symptoms of vaginal infection. In the 2nd study, T. vaginalis was detected using PCR and wet mount microscopy in 131 asymptomatic pregnant women.Results: Among the women with symptoms of vaginitis, 7 (13.5%) were PCR-positive for T. vaginalis. Six of the PCR-positive women, but none of the PCR-negative women, were culture-positive for this organism. All but 1 of the women with candidal vaginitis or bacterial vaginosis were PCR-negative for T. vaginalis. Among the asymptomatic pregnant women, all of whom were negative for T. vaginalis by wet mount, l0 (7.6%) were PCR-positive for T. vaginalis.Conclusions: PCR offers a rapid and sensitive alternative to culture and microscopy for the detection of T. vaginalis vaginal infections in both symptomatic and asymptomatic women.     

Effects of bicarbonate- and lactate-buffered replacement fluids on cardiovascular outcome in CVVH patients

BACKGROUND: Bicarbonate-buffered replacement fluid (RF-bic) in continuous venovenous hemofiltration (CVVH) may be superior to lactate-buffered replacement fluid (RF-lac) in acute renal failure. In an open, randomized, multicenter study, we investigated the effects of RF-bic and RF-lac on cardiovascular outcome in patients requiring CVVH following acute renal failure. METHODS: One hundred seventeen patients between the age of 18 and 80 years were randomized to CVVH either with RF-bic (N = 61) or RF-lac (N = 56). Patients were treated with CVVH for five days or until either renal function was restored or the patient was removed from the study. Data were analyzed on day 5 or according to the "last observation carried forward" (LOCF) option. Adverse events were classified according to the WHO-Adverse Reaction Terminology system. RESULTS: Blood lactate levels were significantly lower and blood bicarbonate levels were significantly higher in patients treated with RF-bic than in those treated with RF-lac (lactate, 17.4 +/- 8.5 vs. 28.7 +/- 10.4 mg/dL, P < 0.05; bicarbonate, 23.7 +/- 0.4 vs. 21.8 +/- 0.5 mmol/L, P < 0. 01). The number of hypotensive crises was lower in RF-bic-treated patients than in RF-lac-treated patients (RF-bic 14 out of 61 patients, RF-lac in 29 out of 56 patients; 0.26 +/- 0.09 vs. 0.60 +/- 0.31 episodes per 24 h, P < 0.05). Nine out of 61 patients (15%) treated with RF-bic and 21 out of 56 patients (38%) treated with RF-lac developed cardiovascular events during CVVH therapy (P < 0. 01). A multiple regression analysis showed that the occurrence of cardiovascular events was dependent on replacement fluid and previous cardiovascular disease and not on age or blood pressure. Patients with cardiac failure died less frequently in the group treated with RF-bic (7 out of 24, 29%) than in the group treated with RF-lac (12 out of 21, 57%, P = 0.058). In patients with septic shock, lethality was comparable in both groups (RF-bic, 10 out of 27, 37%; RF-lac, 7 out of 20, 35%, P = NS). CONCLUSIONS: The results show that the administration of RF-bic solution was superior in normalizing acidosis of patients without the risk of alkalosis. The data also suggest that the use of RF-bic during CVVH reduces cardiovascular events in critically ill patients with acute renal failure, particularly those with previous cardiovascular disease or heart failure.