GENOMES UNCOUPLED1 plays a key role during the de-etiolation process in Arabidopsis

One of the most dramatic challenges in the life of a plant occurs when the seedling emerges from the soil and exposure to light triggers expression of genes required for establishment of photosynthesis. This process needs to be tightly regulated, as premature accumulation of light-harvesting proteins and photoreactive Chl precursors causes oxidative damage when the seedling is first exposed to light. Photosynthesis genes are encoded by both nuclear and plastid genomes, and to establish the required level of control, plastid-to-nucleus (retrograde) signalling is necessary to ensure correct gene expression. We herein show that a negative GENOMES UNCOUPLED1 (GUN1)-mediated retrograde signal restricts chloroplast development in darkness and during early light response by regulating the transcription of several critical transcription factors linked to light response, photomorphogenesis, and chloroplast development, and consequently their downstream target genes in Arabidopsis. Thus, the plastids play an essential role during skotomorphogenesis and the early light response, and GUN1 acts as a safeguard during the critical step of seedling emergence from darkness.

A fully assembled plastid-encoded RNA polymerase complex detected in etioplasts and proplastids in Arabidopsis

The plastid-encoded genes of higher plants are transcribed by at least two types of RNA polymerases, the nuclear-encoded RNA polymerase (NEP) and the plastid-encoded RNA polymerase (PEP). In mature photosynthesizing leaves, the vast majority of the genes are transcribed by PEP. However, the regulatory mechanisms controlling plastid transcription during early light response is unclear. Chloroplast development is suggested to be associated with a shift in the usage of the primary RNA polymerase from NEP to PEP as the expression of the plastid-encoded photosynthesis genes is induced upon light exposure. Assembly of the PEP complex has been suggested as a rate-limiting step for full activation of plastid-encoded photosynthesis gene expression. However, two sigma factor mutants, sig2 and sig6, with reduced PEP activity, showed significantly lower expression of the plastid-encoded photosynthesis genes already in the dark and during the first hours of light exposure indicating that PEP activity is required for basal expression of plastid-encoded photosynthesis genes in the dark and during early light response. Furthermore, in etioplasts and proplastids a fully assembled PEP complex was revealed on Blue Native PAGE. Our results indicate that a full assembly of the PEP complex is possible in the dark and that PEP drives basal transcriptional activity of plastid-encoded photosynthesis genes in the dark. Assembly of the complex is most likely not a rate-limiting step for full activation of plastid-encoded photosynthesis gene expression which is rather achieved either by the abundance of the PEP complex or by some posttranslational regulation of the individual PEP components.

The PIP Peptide of INFLORESCENCE DEFICIENT IN ABSCISSION Enhances Populus Leaf and Elaeis guineensis Fruit Abscission

The programmed loss of a plant organ is called abscission, which is an important cell separation process that occurs with different organs throughout the life of a plant. The use of floral organ abscission in Arabidopsis thaliana as a model has allowed greater understanding of the complexities of organ abscission, but whether the regulatory pathways are conserved throughout the plant kingdom and for all organ abscission types is unknown. One important pathway that has attracted much attention involves a peptide ligand-receptor signalling system that consists of the secreted peptide IDA (INFLORESCENCE DEFICIENT IN ABSCISSION) and at least two leucine-rich repeat (LRR) receptor-like kinases (RLK), HAESA (HAE) and HAESA-LIKE2 (HSL2). In the current study we examine the bioactive potential of IDA peptides in two different abscission processes, leaf abscission in Populus and ripe fruit abscission in oil palm, and find in both cases treatment with IDA peptides enhances cell separation and abscission of both organ types. Our results provide evidence to suggest that the IDA-HAE-HSL2 pathway is conserved and functions in these phylogenetically divergent dicot and monocot species during both leaf and fruit abscission, respectively.

The plant hormone auxin directs timing of xylem development by inhibition of secondary cell wall deposition through repression of secondary wall NAC-domain transcription factors

Wood formation in higher plants is a complex and costly developmental process regulated by a complex network of transcription factors, short peptide signals and hormones. Correct spatiotemporal initiation of differentiation and downstream developmental stages is vital for proper wood formation. Members of the NAC (NAM, ATAF1/2 and CUC) family of transcription factors are described as top level regulators of xylem cell fate and secondary cell wall (SCW) deposition, but the signals initiating their transcription have yet to be elucidated. We found that treatment of Populus stems with auxin repressed transcription of NAC transcription factors associated with fiber and SCW formation and induced vessel-specific NACs, whereas gibberellic acid (GA) induced the expression of both classes of NAC domain transcription factors involved in wood formation. These transcriptional changes were reflected in alterations of stem anatomy, i.e. auxin treatment reduced cell wall thickness, whereas GA had a promotive effect on SCW deposition and on the rate of wood formation. Similar changes were observed on treatment of Arabidopsis thaliana stems with GA or the synthetic auxin NAA. We also observed corresponding changes in PIN5 overexpressing lines, where interference with auxin transport leads to premature SCW deposition and formation of additional fiber bundles. Together, this suggests wood formation is regulated by an integrated readout of both auxin and GA, which, in turn, controls expression of fiber and vessel specific NACs.

A Local Auxin Gradient Regulates Root Cap Self-Renewal and Size Homeostasis

Organ size homeostasis, compensatory growth to replace lost tissue, requires constant measurement of size and adjustment of growth rates. Morphogen gradients control organ and tissue sizes by regulating stem cell activity, cell differentiation, and removal in animals [1-3]. In plants, control of tissue size is of specific importance in root caps to protect the growing root tip from mechanical damage [4]. New root cap tissue is formed by the columella and lateral root-cap-epidermal stem cells, whose activity is regulated through non-dividing niche-like cells, the quiescent center (QC) [4, 5]. Columella daughter cells in contact with the QC retain the potency to divide, while derivatives oriented toward the mature cap undergo differentiation. The outermost columella layers are sequentially separated from the root body, involving remodeling of cell walls [6]. Factors regulating the balance between cell division, elongation, and separation to keep root cap size constant are currently unknown [4]. Here, we report that stem cell proliferation induced cell separation at the periphery of the root cap, resulting in tissue size homeostasis. An auxin response gradient with a maximum in the QC and a minimum in the detaching layer was established prior to the onset of cell separation. In agreement with a mathematical model, tissue size was positively regulated by the amount of auxin released from the source. Auxin transporters localized non-polarly to plasma membranes of the inner cap, partly isolating separating layers from the auxin source. Together, these results are in support of an auxin gradient measuring and regulating tissue size.

Establishment of Photosynthesis through Chloroplast Development Is Controlled by Two Distinct Regulatory Phases

Chloroplasts develop from undifferentiated proplastids present in meristematic tissue. Thus, chloroplast biogenesis is closely connected to leaf development, which restricts our ability to study the process of chloroplast biogenesis per se. As a consequence, we know relatively little about the regulatory mechanisms behind the establishment of the photosynthetic reactions and how the activities of the two genomes involved are coordinated during chloroplast development. We developed a single cell-based experimental system from Arabidopsis (Arabidopsis thaliana) with high temporal resolution allowing for investigations of the transition from proplastids to functional chloroplasts. Using this unique cell line, we could show that the establishment of photosynthesis is dependent on a regulatory mechanism involving two distinct phases. The first phase is triggered by rapid light-induced changes in gene expression and the metabolome. The second phase is dependent on the activation of the chloroplast and generates massive changes in the nuclear gene expression required for the transition to photosynthetically functional chloroplasts. The second phase also is associated with a spatial transition of the chloroplasts from clusters around the nucleus to the final position at the cell cortex. Thus, the establishment of photosynthesis is a two-phase process with a clear checkpoint associated with the second regulatory phase allowing coordination of the activities of the nuclear and plastid genomes.

Redox regulation of PEP activity during seedling establishment in Arabidopsis thaliana

Activation of the plastid-encoded RNA polymerase is tightly controlled and involves a network of phosphorylation and, as yet unidentified, thiol-mediated events. Here, we characterize PLASTID REDOX INSENSITIVE2, a redox-regulated protein required for full PEP-driven transcription. PRIN2 dimers can be reduced into the active monomeric form by thioredoxins through reduction of a disulfide bond. Exposure to light increases the ratio between the monomeric and dimeric forms of PRIN2. Complementation of prin2-2 with different PRIN2 protein variants demonstrates that the monomer is required for light-activated PEP-dependent transcription and that expression of the nuclear-encoded photosynthesis genes is linked to the activity of PEP. Activation of PEP during chloroplast development likely is the source of a retrograde signal that promotes nuclear LHCB expression. Thus, regulation of PRIN2 is the thiol-mediated mechanism required for full PEP activity, with PRIN2 monomerization via reduction by TRXs providing a mechanistic link between photosynthetic electron transport and activation of photosynthetic gene expression.

The plastid-encoded RNA polymerase PEP is regulated according to plastid redox state. Here, the authors show that the redox-regulated PRIN2 protein is reduced to monomeric form in a thiol-dependent manner in response to light and that PRIN2 monomers are required for PEP activity and retrograde signaling.

A quantitative model of the phytochrome-PIF light signalling initiating chloroplast development

The components required for photosynthesis are encoded in two separate genomes, the nuclear and the plastid. To address how synchronization of the two genomes involved can be attained in early light-signalling during chloroplast development we have formulated and experimentally tested a mathematical model simulating light sensing and the following signalling response. The model includes phytochrome B (PhyB), the phytochrome interacting factor 3 (PIF3) and putative regulatory targets of PIF3. Closed expressions of the phyB and PIF3 concentrations after light exposure are derived, which capture the relevant timescales in the response of genes regulated by PIF3. Sequence analysis demonstrated that the promoters of the nuclear genes encoding sigma factors (SIGs) and polymerase-associated proteins (PAPs) required for expression of plastid encoded genes, contain the cis-elements for binding of PIF3. The model suggests a direct link between light inputs via PhyB-PIF3 to the plastid transcription machinery and control over the expression of photosynthesis components both in the nucleus and in the plastids. Using a pluripotent Arabidopsis cell culture in which chloroplasts develop from undifferentiated proplastids following exposure to light, we could experimentally verify that the expression of SIGs and PAPs in response to light follow the calculated expression of a PhyB-PIF3 regulated gene.

Writing an article for the European Annals of Otorhinolaryngology, Head and Neck Surgery: rights and responsibilities

Based on a review of the literature published on medical writing, the authors discuss the rules to respect in terms of both structure and substance to facilitate publication of studies in the European Annals of Otorhinolaryngology, Head and Neck Surgery. The main errors leading to an article's being rejected are detailed and analyzed.

Glioblastoma multiforme mimicking a frontal abscess after surgery for a large vestibular schwannoma

OBJECTIVES

Routine vestibular schwannoma surgery can result in serious and potentially lethal infectious complications. A high degree of vigilance is necessary to diagnose these uncommon infections and in case of postoperative neurological symptoms, brain magnetic resonance imaging should be performed to eliminate a brain abscess. In some cases, the final diagnosis is not the expected one.

CLINICAL PRESENTATION

A 39-year-old man presented three months postoperatively after a vestibular schwannoma removal by translabyrinthin approach with a rapid and progressive history of headaches, confusion, and left hemi paresis with fever. The brain CT and MRI were in favour of a delayed postoperative frontal abscess.

TECHNIQUE

A biopsy under stereotactic guidance was performed. Histopathologic examination revealed WHO grade 4 glioblastoma multiforme.

CONCLUSION

Symptoms and signs of glioblastoma multiforme are congruent with brain abscess. Its rapid evolution, the normality of the first magnetic resonance imaging, and its radiological aspect made it a differential diagnosis of a postoperative brain abscess and should be systematically researched.

[Tympanic membrane perforation and tympanoplasty]

OBJECTIVES

To report anatomic and physiologic characteristics of the tympanic membrane, to discuss the etiology and pathogenesis of tympanic perforation, and to discuss its management.

MATERIAL AND METHODS

After a review of the literature, different surgical techniques and the postoperative results were evaluated.

RESULTS

The rate of tympanic membrane closure is greater than 90% for the majority of authors. Age, mucosa inflammation, pathological contralateral ear (perforation, otitis media, cholesteatoma), and surgical experience influence this result.

DISCUSSION

Even if surgical results are good, abstention must always be proposed and all complications must be explained.

CONCLUSION

Palisade cartilage tympanoplasty is an effective technique for both tympanic membrane closures.

[Endoscopic staple diverticulostomy for Zenker's diverticulum]

OBJECTIVE

Retrospective study to evaluate the efficacy and safety of endoscopic stapled diverticulotomy of patients with Zenker's diverticulum.

METHODS

Twenty-two patients with Zenker's diverticulum were evaluated. All patients had a preoperative barium swallow, which confirmed the Zenker diverticulum.

SURGICAL PROCEDURE

Patients underwent an attempted endoscopic resection of the Zenker diverticulum using the endoscopic stapling technique. If unsuccessful, an open approach was then taken. All patients were seen in follow-up within one and then at six months after surgery and had a barium swallow during the first month.

RESULTS

The patient's mean age was 74 years. The operation lasted a mean of 20minutes. Conversion to open surgery was required in five patients, which lasted a mean 20minutes. No postoperative morbidity or mortality was recorded. In two patients with a small diverticulum (2cm), persistent discomfort with no dysphagia or regurgitation was noted. The barium swallow demonstrated a persistent diverticulum without a neck.

CONCLUSION

Endoscopic staple diverticulotomy is an excellent first-intention method to surgically correct Zenker's diverticulum in many patients. It is a technique with a significantly shorter operative time, hospital stay, time to resumption of oral feeding and lower mortality and fewer morbidity complications.

Balance in healthy individuals assessed with Equitest: maturation and normative data for children and young adults

OBJECTIVE

The purpose of the present prospective study was to obtain normative data for Equitest computerized dynamic posturography (CDP) in children and young adults and to observe the balance maturation process.

METHODS

Equilibrium pattern and SOT of 195 healthy children aged from 6 to 14 years were compared to those of 64 young adults aged 20 years, using Equitest.

RESULTS

The mean stability scores for children progressively improve with age and are significantly lower than those of young adults. Furthermore, sensory organization scores were lower in children compared to young adults, whereas visual preference scores were similar for the whole studied groups.

CONCLUSIONS

According to previous literature, it may be stressed that due to a presumed incomplete development of vestibular system and central nervous system integration, children unlike young adults have lower equilibrium scores, especially when visual information was not available or was incorrect. Our results confirm previous ones obtained in children and young adults with Equitest CDP. This study also provides Equitest data for these age groups, which complete those that have been previously reported.

[Predictive factors of facial palsy of the acoustic neurinoma after retrosigmoid surgery: 230 cases]

OBJECTIVES

To determine predictive factors influencing postoperative facial palsy during retro sigmoid approach in vestibular schwannoma surgery.

MATERIAL AND METHODS

Retrospective study over 230 patients with vestibular schwannoma, mostly stade I and II, operated by retro sigmoid approach, by the same oto neuro chirurgical team between 1993 and 2004. Pre and post operative parameters taken into consideration: quantitative: age and sex, audiometric parameters, duration of clinical symptoms; qualitative: tumor anatomic factors and facial nerve function according to House Brackmann classification.

RESULTS

8 days after surgery, 92% of patients have a normal or subnormal facial nerve function, 5% a facial paresis and 3% a paralysis. After one year, only 4% of patients still have a grade III to VI paralysis. Latency of vertigo with facial nerve paralysis is 4.33 vs. 1.97 year in absence of paralysis. Hearing conservation is 85% without facial nerve paralysis vs. 58% with facial nerve paralysis; Wave III latency (PEAP) with facial nerve paralysis is 4.54 vs. 4.28 ms if not.

CONCLUSION

Significant predictive factors of facial nerve palsy outcome are: age, post surgery hearing conservation, wave III latency, difficulty in tumor dissection, vertigo latency.

[Traumatic luxation of the stapes: radiology and surgical outcome]

OBJECTIVES

To describe the value of high resolution computed tomography scan (HRCT scan) in post traumatic hearing loss.

METHOD

HRCT scan of the temporal bone in millimetric cut with axial and coronal views was performed.

RESULTS

CT scan confirmed pneumolabyrinth with intact stapes depressed deeply into the vestibule. Surgical exploration was performed and the stapes was gently removed from the vestibule.

CONCLUSION

CT scan confirmed the diagnosis and studied the stapes integrity. Hearing deteriorated postoperatively is increased in case of stapes fracture. When a luxation of the stapes into the vestibule is suspected, it is important to determine how deeply and whether it is fractured. When such a case is encountered, high resolution CT scan of the temporal bone must be performed to confirm the diagnosis and to confirm integrity of the stapes.

[Physiological changes in balance control of adults aged 20 to 60 years assessed with Equitest]

OBJECTIVES

The sense of balance depends on many factors including age. A considerable amount of time is spent in medical clinics attempting to identify potential balance problems and retrain individuals with posture and balance limitations. Since the past decades the development of computerized dynamic posturography (CDP) provided the clinicians a tool to objectively assess balance disorders. The aim of this study was to evaluate physiological changes in balance control of adults aged from 20 to 60 years.

MATERIAL AND METHODS

108 healthy adults volunteers were involved in the study. The Equitest CDP was used to record equilibrium pattern in four age groups: "a" 20-30 years old, "b" 3040 years old, "c" 40-50 years old and "d" 50-60 years old.

RESULTS

Equilibrium patterns worsen progressively with age in the studied age groups, especially vestibular pattern, whereas visual dependence increases.

CONCLUSION

Ours results show that: 1- presbyvestibulia takes place progressively with age. 2- between 20 and 60 years old, normative data should be established by decade age steps. 3- From a preventive point of view raises the question if this evolution is uneluctable or could be counteracted by physical training or adapted treatment.

[Community-acquired acute maxillary sinusitis or rhinosinusitis in adults in France: current management]

Sinus infections, often viral, are a common reason for physician visits. The multiplicity of clinical presentations makes its diagnosis difficult. The problem is to recognize bacterial infection without additional testing, except in cases of treatment failures, complications or relapse. Patients with signs suggestive of rhinosinusitis fall into one of four basic clinical situations: common colds, 'doubtful' rhinosinusitis, apparent acute maxillary bacterial rhinosinusitis, and complications. Anterior rhinoscopy may help confirm diagnosis. Current bacterial epidemiology is based on the results of clinical studies, microbial ecology, and samples taken in cases of treatment failure. The two bacteria isolated most frequently are Streptococcus pneumoniae and Haemophilus influenzae, both of which pose resistance problems. Moraxella catarrhalis, Streptococcus pyogenes and Staphylococcus aureus are isolated less often. The dominant issue in management of acute rhinosinusitis is whether to use antibiotic or symptomatic treatment. For viral infections, antibiotic therapy is useless and highly inadvisable. For 'doubtful' infections, symptomatic treatment is likely to lead to recovery. The use of non-recommended antibiotics also increases the risk of selection of resistant bacteria. When bacterial rhinosinusitis is strongly suspected, recourse to antibiotic treatment is recommended in view of the benefits in this situation (AFSSAPS 2005). This treatment is probabilistic, should be decided at the end of the consultation, and follows the AFSSAPS guidelines.

Efficacité et tolérance de la télithromycine dans le traitement des sinusites maxillaires aiguës

The aim of this study was to evaluate the efficacy and tolerance of 5 days of telithromycin (800 mg once a day) in the treatment of bacteriologically proven acute maxillary sinusitis (AMS).

DESIGN

Two hundred and sixty-three patients with a clinically diagnosed AMS and purulent rhinorrhea were included in this prospective, multicenter, non-comparative open-labeled French study. Pus was sampled from the middle meatus before inclusion. The bacterial origin of the infection was confirmed by a scientific committee (presence of leucocytes/bacteria on direct microscopic examination of pus, and positive culture).

RESULTS

Seven to 14 days after the end of the treatment the clinical success rate (cure and improvement) was 91% (63/69 patients) in the per protocol bacteriologically documented (PPb) population and 90% (231/257 patients) in the modified intent-to-treat population. The main strains identified in the 69 patients of PPb population were Streptococcus pneumoniae (47.8%, of which 15 strains with reduced susceptibility to penicillin and 15 erythromycin resistant strains), Haemophilus influenzae (14.5%), Branhamella catarrhalis (8.7%) and Streptococcus aureus (29.0%). Drug tolerance was assessed on 263 patients as satisfactory with mainly gastro-intestinal disorders considered to be related to the treatment in 7.6% of patients. No serious adverse event related to the study drug was reported.

CONCLUSION

The efficacy of telithromycin 800 mg once daily for 5 days is confirmed in the treatment of AMS, even for those due to S. Pneumoniae.

Pre- and intraoperative predictive factors of facial palsy in vestibular schwannoma surgery

CONCLUSION

S These results support previous ones with regard to FN risk factors in VS surgery. However, they also provide new preoperative factors that influence postoperative FN function, such as clinical symptoms, the nature of the surgical procedure (use of laser) and ABR results.

OBJECTIVE

To determine pre- and perioperative factors influencing facial nerve (FN) outcome in vestibular schwannoma (VS) surgery.

MATERIAL AND METHODS

A total of 424 patients undergoing VS surgery were included in this retrospective study. Patients were divided into two groups according to the existence or absence of a FN palsy during the 8 days following surgery (Groups 1 and 2, respectively). Various parameters were evaluated preoperatively as follows. Quantitative parameters: age; duration of clinical symptoms; pure-tone audiometry (PTA) results; speech reception threshold; speech discrimination score; auditory brainstem response (ABR) results; and transient-evoked otoacoustic emission amplitude. Qualitative parameters: gender; side of the tumor; angle between the tumor and the internal auditory canal (VS/IAC angle) < or = or > 30 degrees; MRI aspect (n = 69); surgical approach; ease of the surgical procedure, the use or non-use of laser dissection; and the histological Antoni's type of the tumor. RESULTS Pre- and perioperative factors that differed significantly between Groups 1 and 2 were as follows. Quantitative factors: tinnitus duration was longer and PTA and ABR results were worse in Group 1. Qualitative factors: heterogenous/cystic MRI aspect, use of retrosisgmoid and middle fossa approaches, easy surgical procedure, dissection without laser and Antoni's type A were more frequently found in Group 1.

[Treatment of functional signs of acute maxillary rhinosinusitis in adults. Efficacy and tolerance of administration of oral prednisone for 3 days]

OBJECTIVE

Acute maxillary rhinosinusitis (AMRS) is a pathology in which the pain is often severe and requires appropriate treatment. Although the use of antibiotics is widely documented, the interest of short cycles of corticosteroids in the treatment of the functional manifestations of AMRS is based on professional experience. The aim of this study was to assess the efficacy and tolerance to prednisone administered for 3 days in addition to antibiotherapy in patients presenting with an AMRS.

METHOD

This was a double blind, randomised study in parallel groups and controlled versus a placebo, involving patients aged over 18, presenting with an AMRS confirmed by X-ray and endoscopy, having developed less than 5 days and complaining of spontaneous pain assessed as >or=50 millimetres on a visual analog scale (VAS). Together with cefpodoxime, the patients received either prednisone (0.8 to 1.2 mg/kg) for 3 days or a placebo. The primary efficacy endpoint was the mean of the differences versus the baseline value of pain (MPID - mean pain intensity difference) assessed on the VAS from Day 1 to Day 3. The secondary endpoints assessed were the mean of the differences in intensity of nasal obstruction, assessed in the same way as the MPID, the time lapse before the orally expressed relief of the pain (PRID - pain reflief intensity difference) and the administration of paracetamol during the first 3 days.

RESULTS

289 patients (placebo 147, prednisone 142) were assessable for analysis in intent-to-treat (ITT). The global spontaneous pain on inclusion, measured by a VAS was of 73.0 +/- 14.1 mm. The assessments made during the first 3 days of treatment showed a statistically significant difference in favour of the prednisone group regarding MPID: - 4.82 mm (CI 95% -9.25; -0.40) (p=0.03), nasal obstruction - 5.0 mm (CI 95% -9.1; -0.8) (p=0.02) and consumption of paracetamol (p=0.03). There was no difference between the two groups after the end of the antibiotherapy. The tolerance measured throughout the study was comparable between the two groups.

CONCLUSION

This study clearly showed the efficacy of a short course of oral prednisone (3 days), versus a placebo, in the treatment of the functional signs of acute maxillary rhinosinusitis with severe pain in adults in addition to an appropriate antibiotic treatment.

A prospective, multicentre study of moxifloxacin concentrations in the sinus mucosa tissue of patients undergoing elective surgery of the sinus

A pharmacokinetic study was carried out to determine moxifloxacin concentrations in sinus tissue, after oral moxifloxacin 400 mg once daily for 5 days to patients with chronic sinusitis, undergoing elective sinus surgery. Patients were randomly allocated to one of seven treatment groups, in which tissues were sampled 2, 3, 4, 6, 12, 24 or 36 h post-dose. A control group with non-infected nasal polyps was also included. Forty-eight patients (13 female, 35 male, mean age 47.1 years) were allocated to one of each active treatment group (n = 42) or to the control group (n = 6). Tissue and plasma samples were taken simultaneously and stored frozen until assayed by HPLC. Thirty-nine patients were fully valid for pharmacokinetic analysis. The geometric mean moxifloxacin plasma concentration increased from 2.32 mg/L at 2 h to a maximum of 3.37 mg/L at 4 h post-dose, decreasing to 0.37 mg/L at 36 h post-dose. The moxifloxacin concentration in sinus mucosa was consistently greater than that in plasma being 4.56-5.73 mg/kg from 2 to 6 h and 2.81-1.25 mg/kg from 12 to 36 h post-dose. The elimination rates in plasma and sinus tissues were similar. The tissue/plasma ratio was c. 200% between 2 and 6 h, and up to 328.9% at 36 h. Results were similar whatever the site of tissue sampling (maxillary sinus, anterior ethmoid sinus or nasal polyps). Tissue levels exceeded the MIC(90) of all pathogens commonly causing acute sinusitis (e.g. 5-30 x MIC for Streptococcus pneumoniae: 0.25 mg/L). These results sup-port the use of moxifloxacin 400 mg once daily as a regimen for the treatment of sinus infections.

Short therapy with amoxicillin-clavulanate and corticosteroids in acute sinusitis: results of a multicentre study in adults

Evolution of bacterial resistance shortens antibiotic treatment in ENT infections. The efficacy and tolerance of amoxicillin-clavulanate (ACA), with and without associated short steroid therapy, was evaluated in acute sinusitis of adults at a dosage of 1.5 g/d for 5 d vs. 10 d. This multicentre, randomized, double-blind, placebo-controlled study included 433 patients, 417 of whom were suitable for intent-to-treat (ITT) analysis. The therapeutic success rate in the ITT population, assessed according to strict clinical and radiological criteria, was respectively, 80% and 85% in the 5-d and 10-d treatment groups. Due to the statistical risks that were evidenced, the 2 durations of treatment could not be considered equivalent. The analysis of medical history shows that some risk factors (recurrence of sinusitis, previous surgical sinus drainage) seem to promote therapeutic failure and that 5-d treatment is inappropriate in these patients. The persistence of therapeutic success on day 30 was not influenced by the initial duration of treatment. The efficacy and good tolerance of ACA in acute sinusitis in adults were confirmed. Further studies will be needed to define the indications of short treatments better, which seem to be indicated in the absence of specific risk factors.

[Inflammation and acute otitis media]

1. EPITHELIUM OF THE MIDDLE EAR: The middle ear has a respiratory type epithelium. The mucus is produced by mucosal and by submucosal cells in the Eustachian tube. 2. LYMPHOID TISSUE: The defensive barrier of the mucosa is potentialized by lymphoid tissue in the middle ear that produces a local specific immune response. Bacterial and viral antigens can induce an inflammatory reaction. 3. TUBOTYMAPNIC CAVITIES: The humoral immune system (B lymphocytes) secreting IgG, IgA and IgM) and cell mediated response (T lymphocytes) are active in the tubotympanic cavities. 4. MAST CELLS: Present in contact with vessels and nervous fibers of the tubotympanic chorion, mast cells are activated by IgE linkage to antigens, leading to local allergic inflammatory phenomena with production of histamine, C leukotrienes, platelet activating factor (PAF) and cytokines. 5. MAINTAINING OPEN CAVITIES: During the inflammatory reaction, mucus-secreting cells are stimulated and their glycoprotein secretions are modified. Since the middle ear epithelium has a water-absorption action contributing to aeration of the middle ear cavities. 6. CYTOKINE RESPONSE: During acute middle ear otitis, cytokines secreted in response to bacterial and viral lipopolysaccharides include tumor necrosis factor alpha (TNFa) which plays a crucial role: induction of fibroblast proliferation, activation of polymorphonuclears, inhibition of vascular endothelial tissue and B lymphocytes. It facilitates healing of the middle ear infection, but an also induced pathological lesions in case of incomplete repair. 7. BACTERIAL FLORA: Haemophilus influence, Branhamella catarrhalis, and Streptococcus pneumoniae colonize the respiratory epithelium of the middle ear via the Eustachian tube, generally after viral infection. 8. GLUCOCORTICOIDS: Administered before injection of a bacterial endotoxin, glucocorticoids significantly reduce inflammatory phenomena in acute otitis induced in rat models. In acute middle ear models in the guinea pig, corticosteroids reduce lipoperoxidation; free radicals are the cause of the persistence of inflammation in the acute middle ear. 9. NEUTROPHIL MIGRATION: Antibodies blocking cell adhesion molecules (CAM), or instance antiCD11 B and antiCT 18, inhibit polymorphonuclear migration, and could be very useful for the treatment of acute middle ear infection. Use of prostaglandin inhibitors does not significantly reduce the risk of residual effusion at 10 and 30 days after the acute episode. 10.

CLINICAL TRIALS

There is a significant body of scientific evidence proving the efficacy of combining antiinflammatory drugs and antibiotics for first line treatment of middle ear infection to prevent seromucosal otitis.

[Cervical and pharyngeal inflammatory pseudo-tumors, a report of two cases: clinical course and treatment]

The authors report two new cases of inflammatory pseudotumours, sited in the pharynx and neck--sites in which no previous cases have so far been reported in the literature. The aetiology and clinical course of these rare benign tumours remain little understood even today. Their treatment is also not clearly described. This is most often surgical, although medical treatment is often very effective, and is sometimes appropriate. The authors begin by describing these two clinical cases, and then use the literature to give an account of the clinical course and treatment of inflammatory pseudotumours.