Severity of meningococcal infections is related to anthropometrical parameters

BACKGROUND

Invasive meningococcal infections remain an important cause of death in children. In addition, malnutrition has been classically associated with increased severity of infectious diseases. However, in our experience lethal meningococcaemia in clinically malnourished children is extremely rare. Our purpose was to determine whether there is an association between nutritional status and outcome in children with invasive meningococcal infection.

METHODS

We carried out an observational study and prospectively determined anthropometrical parameters in 127 children aged 1 month to 4 years with invasive meningococcal infection seen in our inpatient facilities from August 1999 to May 2004. Severity and survival were the clinical end points analysed.

RESULTS

Children with severe disease had higher weight for age (1.02 vs -0.19) and height for age (1.12 vs -0.58) z scores than those with non-severe disease. Non-survivors had higher weight for age (0.90 vs -0.16) and height for age (0.73 vs -0.57) z scores than survivors. Clinical and biological variables usually accepted as predictors of high mortality or severity in patients with meningococcal infection were not significantly associated with weight for age and height for age z scores.

CONCLUSION

In the present prospective series of children with invasive meningococcal disease, severity and death were linked to anthropometrical parameters and seemed to be associated with a very good nutritional status, which confirmed our previous uncontrolled observations.

Progressive cochleo-vestibular labyrinthitis

OBJECTIVE

We report a rare case of sudden deafness and benign paroxysmal positional vertigo (BPPV) corresponding to a canalithiasis of the ipsilateral left posterior semicircular canal (PSC).

CASE REPORT

The initial examination showed intact lateral semicircular canal (LSC) function. Cerebral MRI results were normal. However evoked otoacoustics emissions were absent in the left ear. The patient developed, in the course of one week, symptoms and signs of an acute unilateral vestibulopathy in the same ear. However there were no change in hearing loss after it.

CONCLUSION

The association of BPPV acute vestibulopathy and sudden deafness is uncommon but usually the former develops well after the second and third. This case is best explained by a vestibulocochlear labyrinthitis.

EXIBIT: An international multicenter phase II trial of gemcitabine and oxaliplatin (GEMOX) in patients with advanced biliary tract cancer

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Background: Biliary tract carcinomas (BTC) are often diagnosed at an advanced/metastatic stage and have a poor prognosis. The combination of gemcitabine and oxaliplatin (GEMOX) showed promising activity in a French Phase II study (4 centers) in advanced BTC (André. Ann Oncol 2004;15:1339–1343). The objective of this study is to further evaluate the efficacy and safety of GEMOX as first-line therapy in patients (pts) with advanced BTC. Methods: Eligible pts were >18 years of age with histologically proven and measurable, locally advanced or metastatic BTC, had an ECOG PS ≤ 2, adequate renal and hematologic functions, bilirubin < 2.5 × upper limit of normal, and no prior malignancy or brain metastases. Gemcitabine 1000 mg/m2 (Day 1) and oxaliplatin 100 mg/m2 (Day 2) were administered every 2 weeks. The primary objective was response rate (RR) by RECIST (one dimension); secondary objectives were progression-free survival (PFS), overall survival (OS), and safety. Here we report an interim analysis of OS and safety. Results: A total of 70 pts were enrolled between April 2003 and April 2005. The median age was 62 years (range 30–83), 40.0% of pts were male, 94.3% had ECOG PS 0–1. Tumor sites were intrahepatic bile ducts (37.1%), gallbladder (31.4%), extrahepatic bile ducts (12.9%), ampulla of Vater (1.4%), intra/extrahepatic bile ducts (1.4%), missing data (15.7%); 98.6% of pts had no prior radiotherapy and 50% had no prior surgery for BTC. Median OS is 8.25 months (68% of pts are dead and 32% have censored data). Sixty-seven pts were evaluable for safety. Grade 3/4 (NCI-CTC v. 2) hematologic toxicities (% of pts) included thrombocytopenia 10.4%, anemia 9.0%, and neutropenia 9.0%. One pt had febrile neutropenia. Grade 3/4 nonhematologic toxicities included pain 10.4%, ALT elevation 9.0%, fatigue 9.0%, infection 10.4%, vomiting 9.0%, sensory neuropathy 4.5%, nausea 4.5%, and diarrhea 3.0%. One patient died during treatment (cause unknown). Conclusions: GEMOX has acceptable toxicity in pts with BTC. Updated efficacy data (RR, PFS, and OS for the entire population and also by tumor sites) will be presented at the meeting.

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Noninvasive monitoring of therapeutic gene transfer in animal models of muscular dystrophies

Muscular dystrophies are a genetically and phenotypically heterogeneous group of degenerative muscle diseases. A subset of them are due to genetic deficiencies in proteins which form the dystrophin-associated complex at the membrane of the myofibers. In this report, we utilized recombinant adeno-associated virus containing a U7 cassette carrying an antisense sequence aimed at inducing exon skipping of the dystrophin gene or containing the alpha-sarcoglycan gene to alleviate the dystrophic phenotype of the mdx and Sgca-null mice, respectively. As these diseases are characterized by cycle of degeneration/regeneration, we postulated that a reporter gene coadministered at the time of the treatment would make it possible to follow the extent of muscle repair. We observed that the murine secreted alkaline phosphatase (muSeAP) level was very much lower in these animal models than in normal mice. Upon treatment of the dystrophic muscle by gene transfer, the level of muSeAP was restored and correlated with the expression of the therapeutic transgene and with the level of muscle improvement. The system described here provides a simple and noninvasive procedure for monitoring the outcome of a therapeutic strategy involving cell survival.

Adeno-Associated Virus Pseudotype 5 Vector Improves Gene Transfer in Arthritic Joints

The potential for gene delivery to joints, using recombinant adeno-associated virus (rAAV) vectors for the treatment of rheumatoid arthritis (RA), has received much attention. Different serotypes have different virion shell proteins and, as a consequence, vary in their tropism for diverse tissues. The aim of this study was to compare the transduction efficiency of different AAV serotypes encoding murine secreted alkaline phosphatase (mSEAP) or Escherichia coli beta-galactosidase for intraarticular gene delivery in an experimental model of arthritis. The vectors contained AAV2 terminal repeats flanking the reporter gene in an AAV1, AAV2, or AAV5 capsid, producing the pseudotypes rAAV-2/1, rAAV-2/2, and rAAV-2/5. Left knee joints of mice with collagen-induced arthritis were injected and transgene expression was analyzed by chemiluminescence or direct in situ staining of frozen sections. We show for the first time that intraarticular gene transfer with AAV- 2/5 was far more efficient than with the other serotypes tested. Transgene expression was detectable as early as 7 days after injection, reached a maximum at 21 days, and was stably expressed for at least 130 days, whereas AAV-2/1- and AAV-2/2-mediated expression levels were barely detectable. These findings provide a practical application for future local AAV-mediated gene therapy trials in RA.

A report of two cases of unilateral vestibulopathie after systemic ototoxic treatment

PURPOSE OF THE STUDY

To present the cases of two patients that developed unilateral vestibular hypofunction after systemic treatment with ototoxic agents, although they manifested symptoms more typical of bilateral vestibular hypofunction.

MATERIAL AND METHODS

The patients were seen after having recovered from their initial illnesses, and both of them denied suffering any spells of vertigo, loss of hearing during the treatment or tinnitus.

RESULTS

In both patients, oscillopsia and vestibular ataxia were of varying intensity. Bedside vestibular examination, caloric and rotatory chair testing, and vestibular evoked myogenic potentials were congruent with a complete unilateral loss of vestibular function. Audiometry was normal in one case whereas in the other, there was a moderate bilateral sensorineural loss of hearing that was present before treatment and that did not change during the course of the treatment.

CONCLUSION

The existence of unilateral vestibular loss was an unsuspected finding but after careful bedside examination, it was confirmed through extensive vestibular testing. However, this infrequent finding responded very well to vestibular rehabilitation. Different mechanisms are proposed to explain this phenomenon, although there is still no clear evidence of which may account for the responses observed.

The subjective visual vertical in benign paroxysmal positional vertigo. A preliminary study

In Benign Paroxysmal Positional Vertigo (BPPV), the existence of otoconial debris in the cupula or canal explains most of the symptoms and signs characteristic of this common inner ear disorder. We have studied the ability of patients with BPPV to correctly determine the subjective visual vertical, as this is a good test to evaluate utricular function. Only 1 of 10 patients with BPPV displayed a clearly abnormal response, and there was no correlation between the side of the lesion and the perceived tilt. This might imply that the limited damage induced by the dislodged otoconia does not disrupt utricular function or that the saccule is the source of the problem.

HLA-A*0201-restricted cytolytic responses to the rtTA transactivator dominant and cryptic epitopes compromise transgene expression induced by the tetracycline on system

The tetracycline-controlled transcription system (Tet-on) is widely used to regulate gene expression in mammalian cells. In gene therapy applications, immune responses to Tet-on proteins such as the rtTA transcription factor have been reported, raising concerns about their occurrence in humans. To monitor the HLA class I cytolytic responses against Tet-on regulators, we characterized the immunogenic CD8+ epitopes within rtTA and tTS regulators using HLA-A*0201 class I transgenic mice. Epitope prediction programs, HLA-A*0201 binding assays, and peptide immunization were used to select a set of immunogenic peptides within rtTA and tTS sequences. To identify further the rejection epitopes, we expressed Tet-on protein components in vivo and found a single dominant rtTA186 CTL epitope in the rtTA tetracycline repressor domain. Target cells expressing rtTA were susceptible to CTL lysis, and rtTA expression compromised muscle transgene engraftment. To reduce the occurrence of immune responses to rtTA protein, we mutated the dominant rtTA186 epitope and found that this leads to the appearance of subdominant epitopes. As a result, we think that an epitope modification strategy is not applicable to blunt the immune response in this model. Moreover, the identification of HLA-A*0201 rtTA epitopes allowed us to demonstrate here that the delivery of the Tet-on system with weakly immunogenic rAAV vectors does not trigger primary CTL responses in mice, in contrast to DNA transfer. Altogether, the existence of HLA-A*0201 rtTA epitopes may lead to the occurrence of immune responses depending on vectors and local inflammation in gene therapy applications involving rtTA-based regulatory systems.

Premature stop codons involved in muscular dystrophies show a broad spectrum of readthrough efficiencies in response to gentamicin treatment

The suppression levels induced by gentamicin on premature stop codons, caused by primary nonsense mutations found in muscular dystrophy patients, were assessed using a very sensitive dual reporter gene assay. Results show that: (i) the effect of gentamicin on readthrough is similar in cultured cells and in vivo in murine skeletal muscle; (ii) a wide variability of readthrough efficiency is obtained, depending on the mutation tested; (iii) due to the complexity of readthrough regulation, efficiency cannot be predicted by the nucleotide context of the stop codon; (iv) only a minority of premature stop codons found in patients show a significant level of readthrough, and would thus be amenable to this pharmacological treatment, given our present understanding of the problem. These results probably provide an explanation for the relative failure of clinical trials reported to date using gentamicin to treat diseases due to premature stop codons, and emphasize that preliminary assays in cell culture provide valuable information concerning the potential efficiency of pharmacological treatments.