Lemierre's syndrome: a report of six cases

OBJECTIVE: Lemierre's syndrome is a rare but severe condition combining pyrexia, cervical pain and pulmonary signs following a pharyngeal infection, usually tonsillitis. This infectious disease is still present in our country despite wide use of antibiotic therapy in pharyngeal infections. METHODS: In a retrospective study conducted between 1995 and 2000 in two departments (infectious diseases and critical care unit) of Nice university hospital (Nice, France), we collected and analysed six cases of Lemierre's syndrome. RESULTS: We describe a serie of 6 cases, all of them female patients of mean age 27. We enrolled healthy patients whose initial symptom was tonsillitis. Most of these patients showed signs of severe sepsis and one died of septic shock. All the others recovered with treatment. The mean time between tonsillitis and first sign of sepsis was seven days. In four cases, patients received a beta- lactam antimicrobial agent with metronidazole. In two cases, patients were treated with amoxicillin-clavulanate. All patients were investigated for the presence of internal jugular vein thrombosis and were treated by anticoagulants when research was positive. CONCLUSIONS: A strong presumptive diagnosis can be made on the basis of clinical presentation, secondarily confirmed by para-clinical data. The prognosis depends on the speed and quality of management. We therefore wished to raise awareness of this condition among our colleagues by reporting our personal experience.     

Amphotropic or Gibbon Ape Leukemia Virus Retrovirus Binding and Transduction Correlates with the Level of Receptor mRNA in Human Hematopoietic Cell Lines

ABSTRACT: The low level of amphotropic retrovirus mediated gene transfer into human hematopoietic stem cells (HSC) has been an impediment to gene therapy for hematopoietic diseases (1). We have previously shown that mouse and human HSC have low levels of the mRNA encoding PiT-2, the amphotropic retrovirus receptor. We hypothesized that the low level of PiT-2 mRNA was responsible for the low frequency of transduction of HSC by amphotropic retroviral vectors (2). In this study we compared the level of PiT-2 and PiT-1, the Gibbon Ape Leukemia Virus receptor (GaLV), in 5 human tissue culture cell lines. PiT-2 and PiT-1 mRNA levels were highest in K562 cells and lowest in HL60 cells. In hematopoietic cell lines, the level of PiT-2 or PiT-1 mRNA correlated directly with retrovirus binding and transduction with the appropriate (amphotropic or GaLV) retrovirus vector. The level of expression of PiT-2 and PiT-1 mRNA could be increased by treatment of HL60 cells with either PMA or Interleukin-1α. The increase in the level of PiT-2 and PiT-1 mRNA correlated with increased transduction with both amphotropic and GaLV retroviral vectors. We conclude that the improved transduction was a direct effect of the increased levels of receptor mRNA and unrelated to changes in the cell cycle status.     

Quorum sensing in Vibrio spp.: the complexity of multiple signalling molecules in marine and aquatic environments

Abstract

Quorum sensing (QS) is a density-dependent mechanism enabling bacteria to coordinate their actions via the release of small diffusible molecules named autoinducers (AIs). Vibrio spp. are able to adapt to changing environmental conditions by using a wide range of physiological mechanisms and many species pose a threat for human health and diverse marine and estuarine ecosystems worldwide. Cell-to-cell communication controls many of their vital functions such as niche colonization, survival strategies, or virulence. In this review, I summarize (1) the different known QS pathways (2) the diversity of AIs as well as their biological functions, and (3) the QS-mediated interactions between Vibrio and other organisms. However, the current knowledge is limited to a few pathogenic or bioluminescent species and in order to provide a genus-wide view an inventory of QS genes among 87 Vibrio species has been made. The large diversity of signal molecules and their differential effects on a particular physiological function suggest that the complexity of multiple signalling systems within bacterial communities is far from being fully understood. I question here the real level of specificity of such communication in the environment and discuss the different perspectives in order to better apprehend QS in natural habitats.