Role of MR cisternography in the diagnosis of cerebrospinal fluid rhinorrhoea with diagnostic nasal endoscopy and surgical correlation

Objectives : To study the usefulness and accuracy of MR cisternography as noninvasive study in the diagnosis of cerebrospinal fluid (CSF) fistula with diagnostic sinonasal endoscopy and surgical correlation. Material and Methods: Twenty four patients with clinically suspected CSF rhinorrhoea were examined for CSF fistula with MR cisternography. The MR imaging technique included 3mm thin T2 weighted coronal and sagittal sections using Fast spin echo. In addition 1.5mm thin T2 weighted coronal sections were also obtained using CISS (Constructive Interference in Steady State) sequence. MR findings were correlated with diagnostic sinonasal endoscopy and surgical findings. Results : MR cisternography demonstrated the presence of fistula in 17 patients, absence of fistula in seven patients. Out of 17 patients with fistula, the diagnosis could be confirmed in 14 patients by diagnostic sinonasal endoscopy/surgery. Out of the seven patients without fistula, there was positive correlation in six patients when they were followed up clinically and by diagnostic nasal endoscopy. However in one patient, fistula was demonstrated on CT cisternography and was confirmed on sinonasal endoscopic surgery. The accuracy, sensitivity of MR cisternography was 96, 94% respectively. Conclusion : MR cisternography is a useful and accurate noninvasive study in localizing the site and extent of CSF fistula.

Towards a consensus on a hearing preservation classification system

CONCLUSION

The comprehensive Hearing Preservation classification system presented in this paper is suitable for use for all cochlear implant users with measurable pre-operative residual hearing. If adopted as a universal reporting standard, as it was designed to be, it should prove highly beneficial by enabling future studies to quickly and easily compare the results of previous studies and meta-analyze their data.

OBJECTIVES

To develop a comprehensive Hearing Preservation classification system suitable for use for all cochlear implant users with measurable pre-operative residual hearing.

METHODS

The HEARRING group discussed and reviewed a number of different propositions of a HP classification systems and reviewed critical appraisals to develop a qualitative system in accordance with the prerequisites.

RESULTS

The Hearing Preservation Classification System proposed herein fulfills the following necessary criteria: 1) classification is independent from users' initial hearing, 2) it is appropriate for all cochlear implant users with measurable pre-operative residual hearing, 3) it covers the whole range of pure tone average from 0 to 120 dB; 4) it is easy to use and easy to understand.

Diagnostic accuracy of 64-slice multidetector computed tomography in evaluation of post-coronary artery bypass grafts in correlation with invasive coronary angiography

64-slice multidetector computed tomography (MDCT) allows more reliable and non-invasive evaluation of the coronary artery bypass grafts for occlusion or stenosis both in symptomatic and asymptomatic patients and also progression of disease in native coronary vessels.

Atypical Presentation of Coarctation of Aorta Mimicking a Spinal Vascular Malformation

Coarctation of the aorta accounts for about 8% of all congenital heart diseases. It usually presents in infancy or later in the third decade depending on its severity. It has a wide spectrum varying from an asymptomatic presentation to cardiac and extracardiac manifestations with neurological complications. Coarctation presenting as a spinal complication is extremely rare. We describe a case of coarctation detected on magnetic resonance imaging (MRI) in a 40-year-old man with an uncommon presentation mimicking a spinal arteriovenous malformation (AVM). To our knowledge, coarctation presenting with a spinal manifestation, resembling an AVM is rare, and has not been reported to date.

An unusual presentation of lipofibromatous hamartoma in an infant. A case report

Lipofibromatous hamartomas are rare benign tumors presenting in the third and fourth decades with a predilection for the upper extremity. We describe an unusual presentation of lipofibromatous hamartoma occurring in a one month old female child, where the lesion showed MR findings resembling that of a vascular malformation.

Diagnosis of Intracranial Epidermoid Rupture by MR Imaging. A Case Report

Intracranial epidermoids are benign tumours arising from retained ectodermal implants. Spontaneous rupture is an important though rare complication of intracranial epidermoid. To our knowledge, MR findings in spontaneous epidermoid rupture have not been well described to date. We report the case of a 60-year-old man who presented with a two day history of headache, altered sensorium and left hemiplegia. A diagnosis of ruptured epidermoid was made based on MR imaging findings which were subsequently proven by histopathology.

Real time PCR for the assessment of CD8+ T cellular immune response after prophylactic vaccinia vaccination

BACKGROUND

The magnitude of specific CD8+ T cell reactivity responsible for vaccine-induced protection against smallpox infection has not yet been fully elucidated. Among other techniques, RT-PCR for the monitoring of cytokine release in effector T cells against tumor and viral antigens has demonstrated a novel promising method.

OBJECTIVE

To determine the functional status of antigen specific CD8+ T cells in healthy participants before and 4 weeks after prophylactic vaccination (Lister strain) against smallpox using quantitative real-time PCR (qRT-PCR).

STUDY DESIGN

Changes of interferon-gamma (IFNgamma) mRNA expression levels on short term ex vivo peptide antigen stimulation were measured. The corresponding specific CD8+ T cell reactivity was then displayed as CD8-normalized IFN-gamma levels (IFN-gamma/CD8 ratio).

RESULTS

We found a 5-9 fold increase of CD8+ T cell reactivity in three out of four vaccinated individuals. The kinetics and strength determined in responders reveal a virus specific T cell effector repertoire pre-vaccination and a corresponding functional state after immunization comparable also to data obtained from tetramer- and ELISPOT analysis.

CONCLUSIONS

Apart from protective vaccinia-specific neutralizing antibodies, the presence of antigen-specific CD8+ T-cells has been demonstrated after vaccinia vaccination. In concordance with others, results from this PCR-based study indicate that this smallpox vaccine induces strong vaccinia virus-specific CD8+ and IFN-gamma producing T cell responses.

Long-term outcomes of laser-assisted uvulopalatoplasty in 168 patients with snoring

Laser-assisted uvulopalatoplasty (LAUP) is an established treatment for snoring. Our institution has been using a modification of the Kamami technique since 1995. Between January 1995 and December 2001, 469 patients underwent LAUP for snoring. A telephone survey of these patients and their partners was conducted retrospectively. One hundred and sixty-eight patients and their partners were interviewed and the findings analysed.Of the 168 patients, 122 had LAUP alone, 42 had LAUP and tonsillectomy and four had LAUP and septoplasty. The median follow-up time was 59 months (range 19 to 98 months).Seventy-four per cent reported improvement at six weeks, 69 per cent reported improvement at nine months and 55 per cent reported improvement at the time of interview. To assess the degree of improvement, patients and their partners were asked to grade any improvement in percentage terms. The mean subjective improvement scores were 57 per cent at six weeks (95 per cent confidence interval (CI) 50-64 per cent), 45 per cent at nine months (95 per cent CI 38-59 per cent) and 30 per cent at the time of interview (95 per cent CI 23-35 per cent). Patients who reported weight gain since surgery did not have a poorer outcome than those who reported no weight change or weight loss. Neither did weight loss predict a better outcome. The procedure was generally well tolerated, with only 30 patients (18 per cent) reporting complications (mainly minor). The benefits of LAUP wane with time and the results are best in the first 12 months following surgery. Our study suggests that 55 per cent of patients selected after sleep studies and sleep nasendoscopy will enjoy long-term benefit.

Suppression of RNA silencing by a geminivirus nuclear protein, AC2, correlates with transactivation of host genes

Bipartite geminiviruses encode a small protein, AC2, that functions as a transactivator of viral transcription and a suppressor of RNA silencing. A relationship between these two functions had not been investigated before. We characterized both of these functions for AC2 from Mungbean yellow mosaic virus-Vigna (MYMV). When transiently expressed in plant protoplasts, MYMV AC2 strongly transactivated the viral promoter; AC2 was detected in the nucleus, and a split nuclear localization signal (NLS) was mapped. In a model Nicotiana benthamiana plant, in which silencing can be triggered biolistically, AC2 reduced local silencing and prevented its systemic spread. Mutations in the AC2 NLS or Zn finger or deletion of its activator domain abolished both these effects, suggesting that suppression of silencing by AC2 requires transactivation of host suppressor(s). In line with this, in Arabidopsis protoplasts, MYMV AC2 or its homologue from African cassava mosaic geminivirus coactivated >30 components of the plant transcriptome, as detected with Affymetrix ATH1 GeneChips. Several corresponding promoters cloned from Arabidopsis were strongly induced by both AC2 proteins. These results suggest that silencing suppression and transcription activation by AC2 are functionally connected and that some of the AC2-inducible host genes discovered here may code for components of an endogenous network that controls silencing.

Promoters, transcripts, and regulatory proteins of Mungbean yellow mosaic geminivirus

Geminiviruses package circular single-stranded DNA and replicate in the nucleus via a double-stranded intermediate. This intermediate also serves as a template for bidirectional transcription by polymerase II. Here, we map promoters and transcripts and characterize regulatory proteins of Mungbean yellow mosaic virus-Vigna (MYMV), a bipartite geminivirus in the genus Begomovirus. The following new features, which might also apply to other begomoviruses, were revealed in MYMV. The leftward and rightward promoters on DNA-B share the transcription activator AC2-responsive region, which does not overlap the common region that is nearly identical in the two DNA components. The transcription unit for BC1 (movement protein) includes a conserved, leader-based intron. Besides negative-feedback regulation of its own leftward promoter on DNA-A, the replication protein AC1, in cooperation with AC2, synergistically transactivates the rightward promoter, which drives a dicistronic transcription unit for the coat protein AV1. AC2 and the replication enhancer AC3 are expressed from one dicistronic transcript driven by a strong promoter mapped within the upstream AC1 gene. Early and constitutive expression of AC2 is consistent with its essential dual function as an activator of viral transcription and a suppressor of silencing.

Suppression of RNA silencing by a geminivirus nuclear protein, AC2, correlates with transactivation of host genes

Bipartite geminiviruses encode a small protein, AC2, that functions as a transactivator of viral transcription and a suppressor of RNA silencing. A relationship between these two functions had not been investigated before. We characterized both of these functions for AC2 from Mungbean yellow mosaic virus-Vigna (MYMV). When transiently expressed in plant protoplasts, MYMV AC2 strongly transactivated the viral promoter; AC2 was detected in the nucleus, and a split nuclear localization signal (NLS) was mapped. In a model Nicotiana benthamiana plant, in which silencing can be triggered biolistically, AC2 reduced local silencing and prevented its systemic spread. Mutations in the AC2 NLS or Zn finger or deletion of its activator domain abolished both these effects, suggesting that suppression of silencing by AC2 requires transactivation of host suppressor(s). In line with this, in Arabidopsis protoplasts, MYMV AC2 or its homologue from African cassava mosaic geminivirus coactivated >30 components of the plant transcriptome, as detected with Affymetrix ATH1 GeneChips. Several corresponding promoters cloned from Arabidopsis were strongly induced by both AC2 proteins. These results suggest that silencing suppression and transcription activation by AC2 are functionally connected and that some of the AC2-inducible host genes discovered here may code for components of an endogenous network that controls silencing.