First Report of Phytophthora ramorum on Ornamental Plants in France.

In April 2002, Phytophthora ramorum was associated with twig blight and brown spots on Rhododendron spp. leaves from a nursery in France. The isolate was identified by its morphological characters on V8 agar: slow growth, deciduous and semipapillate sporangia, and abundant production of large chlamydospores (3). The identification was confirmed by ITS rDNA sequencing. During 2002, P. ramorum was also isolated from diseased Viburnum tinus and V. × bodnantense plants exhibiting symptoms of wilting and stem base discoloration. Subsequently, repeated surveys for P. ramorum were carried out in nurseries and areas surrounding nurseries throughout France. Since 2004, a large range of known hosts were investigated in approximately 2,000 nurseries and 200 other sites each year. P. ramorum was detected exclusively in nurseries at 29 locations in 2002, 9 in 2003, 23 in 2004, 17 in 2005, and 19 in 2006. Rhododendron spp. and occasionally V. tinus were the major hosts. In addition, the pathogen was detected for the first time on Pieris japonica in two nurseries in 2005 and on Camellia sp. in one nursery in 2006 from plants exhibiting leaf and twig blight. In both cases, P. ramorum had already been detected on Rhododendron spp. in the same nurseries. Most of the infected plants were found in northwestern France (Bretagne and Pays-de-la-Loire), or came from this region, which is the main rhododendron-growing area in France. In some cases, plants were imported from Belgium or the Netherlands. P. ramorum was also detected in a nursery in soil close to diseased Rhododendron spp. plants and pond water used for irrigation by using a combination of baiting with Rhododendron spp. leaves and PCR assay with species-specific primers (1). Overall, approximately 1% of the investigated nurseries were found positive each year, and this ratio was quite stable from 2004 to 2006. To date, P. ramorum has not been detected outside of nurseries, although many surveys were conducted on the west coast of France where the risk is considered to be high because of a favorable mild and humid climate and the presence of suitable hosts. In addition, 78 isolates of P. ramorum collected between 2002 and 2004 on Rhododendron spp. and V. tinus were found to be of A1 mating type based on pairings with P. cryptogea A1 and A2 mating types (2). References: (1) K. J. Hayden et al. Phytopathology 94:1075, 2004. (2) S. Werres and B. Zielke J. Plant Dis. Prot. 110:129, 2003. (3) S. Werres et al. Mycol. Res. 105:1155, 2001.

Frontal sinus disease. III. Experimental and clinical factors in failure of the frontal osteoplastic operation.

The surgical approach to frontal sinus disease has been subject to much variation. Experimental evidence for new treatment modalities is quite limited. Frontal osteoplasty, while probably the best procedure to date, has up to a 25 percent failure rate. Possible complications include recurrent disease, incomplete bony obliteration (Macbeth technique), infection of the adipose implant, frontal bossing or depression, and laceration of the dura. Four experimental groups were designed using the canine frontal sinus model. Results indicated that stripping the mucosa in a normal sinus with intact periosteum and a patent nasofrontal duct will not consistently lead to normal mucosal regeneration. Second, the additional factor of removing the periosteum (as in osteoplasty by osteoneogenesis), leads to partial fibrous obliteration complicated by mucocele formation. Third, sinus obliteration by osteoneogenesis was much more consistent with concurrent closure of the nasofrontal duct. Fourth, intentionally leaving a strip of mucosa leads to failure of obliteration by osteoneogenesis 100 percent of the time. Finally, bony-fibrous obliteration increases with time but is still incomplete after one year. In light of these results, fat obliteration with closure of the nasofrontal duct is probably more reliable than obliteration by osteoneogenesis.

Frontal sinus trauma: experimental reconstruction with proplast.

Trauma has become the most common pathologic entity requiring operative intervention in the frontal sinus. Treatment has evolved from simple open drainage to ablation with reconstruction at a later date. Methyl-methacrylate, currently the most widely used alloplastic material, has inherent disadvantages such as two-stage reconstruction, difficulty in handling and molding, and susceptibility to trauma. The present investigation evaluates Proplast, a biocompatible Teflon fluorocarbon polymer implant, in one and two-stage frontal reconstruction following traumatic defects to the canine frontal sinus. Following the loss of anterior or posterior frontal bone, Proplast provided excellent cosmetic reconstruction over a period of one year. Resistance to infection was good, reaction with dura and brain was absent, and cerebrospinal fluid leaks sealed rapidly. In contrast to other alloplastic materials, rapid vascularization and collagen ingrowth lead to stabilization rather than sequestration. Several advantages over alloplastic and metallic implants may give Proplast a unique potential in operative cranioplasty.

Frontal sinus disease. IV. Cellular response to experimentally-induced infection.

The pathogenesis of chronic frontal sinusitis is poorly understood. The canine frontal sinus model was developed to isolate experimentally the variables involved. We have recently determined that blockage of the naso-frontal duct does not, by itself, produce sinusitis or mucocele experimentally. The purpose of the present investigation is to examine the histological and ultrastructural responses of the sinus mucosa to artificially-induced infection. Bone wax was implanted in the canine frontal sinus via an osteoplastic flap, and subsequently removed three months later. Radiological, histological and ultrastructural analysis of the resultant infected mucosa was performed at periods up to one year. The sinus mucosa did not return to normal up to nine months following removal of the infection-inciting foreign body. Persistent changes included epithelial and submucosal thickening, polypoid degeneration, matting of the ciliary carpet, and "bursting" of the ciliary cell bodies. In the light of this and previous experiments, an insidious cycle of events leading to irreversible frontal sinus disease is postulated, requiring the interplay of at least three variables: the infectious insults, the response of the sinus mucosa, and the variable patency of the nasofrontal duct.

An experimental model for the study of endolymphatic hydrops in sharks: implications for the clinician.

In recent years, attention has focused on the role of the endolymphatic sac (ELS) and the endolymphatic duct (ELD) in the pathogenesis of endolymphatic hydrops (ELH). Changes have been noted surgically and radiographically by others in the ELS and ELD in patients with ELH. This report summarizes the development of a shark model with which to study the pathophysiology of ELH. The background material and overall results of anatomic, histopathologic, and ultrastructural studies using the model are presented. Possible implications for the clinical handling of ELH as a result of this work is emphasized.

Local anesthesia in otolaryngology. A re-evaluation.

Almost a half century following attempts to ban its use, cocaine remains at the pinnacle of topical anesthesia in otolaryngology. To understand how nonaddicting synthetic substitutes such as procaine, dibucaine, tetracaine and lidocaine have not totally supplanted cocaine, requires an in-depth analysis of its unique pharmological properties, untoward effects and potential substitutes. Almost all of the reported cocaine deaths occurred after subcutaneous injection; when used topically, cocaine's toxicity has been confined to an occasional reaction. Certain variables under physician control may be manipulated to reduce the chance of reaction to a minimum. For example, intermittent application of a particular dosage results in lower blood levels, and allowing sufficient time between doses reduces the amount necessary to obtain the desired anesthesia. If total dosage is kept below 200 mg there are few reactions. A singular advantage of cocaine over other topical anesthetics is its inherent ability to cause vasoconstriction, thus retarding its own absorption. The addition of a topical vasoconstrictor such as epinephrine is thus redundant, and may actually be harmful as cocaine sensitizes the patient to exogenous epinephrine. Finally, the usual preoperative dosages of barbiturates are entirely inadequate to prevent or treat cocaine reactions. Why, then, have synthetic local anesthetics not replaced cocaine? Inherent differences in topical effectiveness, duration of anesthesia and toxicity provide the answer. Of other local anesthetics possessing topical effectiveness tetracaine is about six times more toxic than cocaine. Dibucaine is as toxic as tetracaine, and lidocaine, while relatively nontoxic, provides only a 15 minute duration of topical anesthesia. A review of cocaine and its potential substitutes thus leads to the conclusion that cocaine is still a vital and necessary instrument in the otolaryngologist's armamentarium, singularly providing excellent topical anesthesia of usable duration, vasoconstriction, and shrinkage of mucous membranes, all with a quite acceptable margin of safety.

Airway intervention in croup and epiglottitis: the changing role of the otolaryngologist.

Recent evidence indicates that endotracheal intubation is supplanting tracheostomy for the short-term treatment of airway obstruction in epiglottitis and croup. Care should be provided by a triumvirate of physicians to include and otolaryngologist, a pediatrician, and an anesthesiologist. Intensive care facilities are also a prerequisite. Standard tracheostomy should be considered in cases requiring intubation longer than 72 hours.

Increased sporulation of vesicular-arbuscular mycorrhizal fungi by manipulation of nutrient regimens.

Adjustment of pot culture nutrient solutions increased root colonization and sporulation of vesicular-arbuscular mycorrhizal (VAM) fungi. Paspalum notatum Flugge and VAM fungi were grown in a sandy soil low in N and available P. Hoagland nutrient solution without P enhanced sporulation in soil and root colonization of Acaulospora longula, Scutellospora heterogama, Gigaspora margarita, and a wide range of other VAM fungi over levels produced by a tap water control or nutrient solutions containing P. However, Glomus intraradices produced significantly more spores in plant roots in the tap water control treatment. The effect of the nutrient solutions was not due solely to N nutrition, because the addition of NH(4)NO(3) decreased both colonization and sporulation by G. margarita relative to levels produced by Hoagland solution without P.