Cardiac perforation following transcatheter PFO closure.

From December 1998 to August 2001, transcatheter closure of patent foramen ovale (PFO) with an Amplatzer PFO occluder has been successfully performed in our center in 102 patients without severe complications. We are reporting the first known case of cardiac perforation by an Amplatzer PFO occluder.     

Automated extraction of genomic DNA from medically important yeast species and filamentous fungi by using the MagNA Pure LC system

A fully automated assay was established for the extraction of DNA from clinically important fungi by using the MagNA Pure LC instrument. The test was evaluated by DNA isolation from 23 species of yeast and filamentous fungi and by extractions (n = 28) of serially diluted Aspergillus fumigatus conidia (10(5) to 0 CFU/ml). Additionally, DNA from 67 clinical specimens was extracted and compared to the manual protocol. The detection limit of the MagNA Pure LC assay of 10 CFU corresponded to the sensitivity when DNA was extracted manually; in 9 of 28 runs, we could achieve a higher sensitivity of 1 CFU/ml blood, which was found to be significant (p 相似文献   

Detection of Haemophilus influenzae type b by real-time PCR

A real-time PCR assay targeting the capsulation locus of Haemophilus influenzae type b (Hib) was developed. The linear detection range was from 1 to 10(6) microorganisms per reaction mixture. No H. influenzae other than Hib or any other control bacteria typically found in the upper respiratory tract was detected.     

Digoxin-like immunoreactive substance in nonoliguric hyperkalemia of the premature infant

Nonoliguric hyperkalemia of premature infants probably results from a transient inhibition of membrane-bound Na+/K+-ATPase during the first 24 h after birth. We hypothesized that the endogenous digitalis-like activity of the serum of premature infants, which inhibits the Na+/K+-ATPase, triggered hyperkalemia. Serum concentrations of potassium ([K+]) and of the digoxin-like immunoreactive substance ([DLIS]) were measured during the first 24 h after birth in 60 infants including 30 infants <30 gestational weeks. Contrary to our hypothesis, there was a negative linear correlation between [DLIS] at birth and [K+] 24 h after birth (r2 = 0.24, p < 0.002). 24 h after birth there was no correlation between [DLIS] and [K+]. Thus, a major role of DLIS in nonoliguric hyperkalemia could not be established.     

Role of mast cells in experimental anti-glomerular basement membrane glomerulonephritis

Recently, divergent reports on the role of mast cells (MC) in different glomerular diseases have brought our attention to their role in an accelerated model of anti-glomerular basement membrane (GBM) glomerulonephritis (GN). Genetically MC-deficient Kit(W)/Kit(W-v) mice, MC-reconstituted Kit(W)/Kit(W-v) mice and Kit+/+ control mice were subjected to anti-GBM GN. Kit(+/+) mice developed moderate proteinuria and glomerular damage following the induction of anti-GBM nephritis. In contrast, proteinuria and glomerular damage were dramatically increased in MC-deficient Kit(W)/Kit(W-v) mice. MC-reconstituted Kit(W)/Kit(W-v) mice showed proteinuria and glomerular damage comparable to Kit+/+ mice. A significant increase in infiltrating T cells and macrophages was detected in MC-deficient Kit(W)/Kit(W-v) mice as compared to Kit+/+ control mice and MC-reconstituted Kit(W)/Kit(W-v) mice. Accordingly, we observed an increase of TGF-beta1 mRNA in kidneys from Kit(W)/Kit(W-v) mice. Interestingly, we did not detect MC in the kidney using either Giemsa staining or RT-real-time PCR, but MC were found in the regional lymph nodes. Finally, mortality of Kit(W)/Kit(W-v) mice was significantly increased after the induction of anti-GBM GN due to uremia. Our report provides the first direct evidence that MC are protective in anti-GBM GN, possibly by modulating the influx of effector T cells and macrophages to inflammatory sites in the kidney.     

Effect of tissue fixatives on telomere length determination by quantitative PCR

Telomere length is a well established marker of cellular senescence and thus biological age. Quantitative PCR allows the determination even from very low amounts of tissue by using telomere specific and single copy gene primers. Comparing a directly processed tissue sample to a 4% formaldehyde fixed one showed a significantly reduced efficiency of PCR reactions (mainly in single copy gene experiments) in a storage time-dependent manner resulting in an artificial increase in reported relative telomere length. This effect was not seen when the tissue was stored in RNA later solution. In summary, telomere length determination from formaldehyde fixed material by quantitative PCR is not a reliable method. Unfortunately therefore, many easily accessible tissue samples from pathology laboratories are unsuitable for this technique.     

HIV-1 Tat increases the adhesion of monocytes and T-cells to the endothelium in vitro and in vivo: implications for AIDS-associated vasculopathy

HIV-1-infected patients exhibit severe damages of the aortic endothelium, develop angioproliferative lesions such as Kaposi's sarcoma (KS), and have an increased risk of cardiovascular diseases and atherosclerosis. An increased adhesion of leukocytes to the endothelium is a common pathogenic parameter of AIDS-associated vascular diseases. Here we show that the HIV-1 Tat protein, a regulatory protein of HIV-1 released by infected cells, and TNF-alpha, a cytokine increased in sera and tissues of HIV-1-infected patients, activate synergistically the adhesion of leukocytes to endothelial cells both in vitro and in vivo. This effect is selectively mediated by HIV-1 Tat, since HIV-1 Nef, another HIV-1 regulatory protein, and the HIV-1 envelope protein gp41, had no effect. In vitro adhesion assays with PBMC and quantitative cell type analysis of adherent cells by FACS demonstrated that HIV-1 Tat selectively activates the adhesion of T-cells and monocytes but not of B-cells. Intravital microscopic studies in mice confirmed the synergistic activity of HIV-1 Tat and TNF-alpha on leukocyte adhesion to the endothelium in vivo. These data indicate that HIV-1 Tat in cooperation with TNF-alpha may contribute to the vascular damage and cardiovascular diseases observed in AIDS patients but also to the prominent extravasation of T-cells and monocytes which is a key process in the formation and progression of KS lesions.     

How much does phase resetting contribute to event-related EEG abnormalities in schizophrenia?

Objective: Patients suffering from schizophrenia demonstrate impaired low frequency electrophysiological responses to stimuli, but it remains unclear whether these abnormalities arise from phase resetting of ongoing oscillations, new phase-locked (evoked) activity or non-phase-locked (induced) activity. Our goal is to clarify the contribution of each of these three processes to the impairment of neural activity during information processing in schizophrenia, by using statistics that do not confound increases in the mean post-stimulus signal with phase resetting. Methods: Thirty-four male schizophrenia patients and 34 healthy matched controls performed an auditory oddball task. We applied the analysis procedure developed by Martinez-Montes et al. [18] based on complex-valued wavelet transform to event-related signal elicited by target stimuli. Results: The largest abnormalities were found for phase-locked delta (1–4 Hz) and non-phase-locked theta (4–8 Hz). Delta phase resetting was moderately impaired and related to symptoms of disorganization. It also predicted evoked theta signal. Conclusion: The substantial reduction of both evoked and induced oscillatory activity in schizophrenia indicates diminished recruitment of brain circuits engaged not only in stimulus-locked perceptual processing but also in more extensive processing less tightly time locked to the stimulus. Although reduced phase resetting makes a lesser contribution, it indicates a deficit in the ability to harness ongoing electrical activity.     

Sequetyping: serotyping Streptococcus pneumoniae by a single PCR sequencing strategy

The introduction of pneumococcal conjugate vaccines necessitates continued monitoring of circulating strains to assess vaccine efficacy and replacement serotypes. Conventional serological methods are costly, labor-intensive, and prone to misidentification, while current DNA-based methods have limited serotype coverage requiring multiple PCR primers. In this study, a computer algorithm was developed to interrogate the capsulation locus (cps) of vaccine serotypes to locate primer pairs in conserved regions that border variable regions and could differentiate between serotypes. In silico analysis of cps from 92 serotypes indicated that a primer pair spanning the regulatory gene cpsB could putatively amplify 84 serotypes and differentiate 46. This primer set was specific to Streptococcus pneumoniae, with no amplification observed for other species, including S. mitis, S. oralis, and S. pseudopneumoniae. One hundred thirty-eight pneumococcal strains covering 48 serotypes were tested. Of 23 vaccine serotypes included in the study, most (19/22, 86%) were identified correctly at least to the serogroup level, including all of the 13-valent conjugate vaccine and other replacement serotypes. Reproducibility was demonstrated by the correct sequetyping of different strains of a serotype. This novel sequence-based method employing a single PCR primer pair is cost-effective and simple. Furthermore, it has the potential to identify new serotypes that may evolve in the future.