Insecticidal activity of a Moroccan strain of Streptomyces phaeochromogenes LD-37 on larvae, pupae and adults of the Mediterranean fruit fly, Ceratitis capitata (Diptera: Tephritidae).

The Mediterranean fruit fly (medfly), Ceratitis capitata, is considered the most important fruit pest worldwide. Its management is mainly based on the use of chemical insecticides. Although these conventional pesticides are effective at high doses, they cause considerable human health and environment problems. Thus, the aim of this study was to assess insecticidal activity of Moroccan actinobacteria against C. capitata. A total of 12 preselected actinobacteria isolated from various Moroccan habitats were screened for their insecticidal activity against larvae, pupae and adults of C. capitata. Four actinobacteria isolates were significantly active against the first-instar larvae, and nine were active against the medfly adult, while no significant mortality was obtained against the third-instar larval and pupal stages. Among the selected isolates, the biological screening revealed that strain Streptomyces LD-37, which showed 99.4% similarity with Streptomyces phaeochromogenes, exhibited the maximal corrected larval mortality of 98%. Moreover, the isolates AS1 and LD-37 showed the maximum significant corrected mortality against adults of 32.5 and 28.2%, respectively. The crude extract obtained from a fermented culture of strain S. phaeochromogenes LD-37 was separated into six fractions by thin layer chromatography. Fractions F3 and F4 caused a significant corrected larval mortality of 66.7 and 53.3%, respectively; whereas the maximum reduction in adult emergence was obtained with fraction F4. This finding could be useful for utilizing S. phaeochromogenes LD-37 as an alternative to chemical insecticides in pest management of C. capitata.

Surgical management of paediatric chronic rhinosinusitis: review of 10 years' experience.

OBJECTIVE: To assess the outcome of children with chronic rhinosinusitis who were managed surgically, over a 10-year study period. METHOD: From January 1999 to December 2008 inclusive, 136 children diagnosed with chronic rhinosinusitis underwent surgery following unsuccessful medical treatment. The operations ranged from adenoidectomy to functional endoscopic sinus surgery. RESULTS: The surgical procedures performed were: adenoidectomy (n=69), antral washouts (n=54), middle meatal antrostomy (n=82), endoscopic ethmoidectomy (n=66), nasal septal reconstruction (n=10), and inferior turbinate outfracture (n=23) or inferior turbinate reductions (n=55). Follow-up duration ranged from 6 months to 9 years (average 3.2 years). Three patients required revision surgery: adenoidectomy in two patients and adenoidectomy with turbinate reductions in another. CONCLUSION: This study demonstrates the benefits of focused surgical treatment for paediatric chronic rhinosinusitis. Surgical treatment can be an appropriate and effective option for children with chronic rhinosinusitis when medical management is unsuccessful.

Free fat grafting in superficial parotid surgery to prevent Frey's syndrome and improve aesthetic outcome.

BACKGROUND: Frey's syndrome and cosmesis are important considerations in parotid surgery. Placement of an interpositional barrier can prevent these complications; however, surgical technique and efficacy remain controversial. METHODS: A prospective case series was collected comprising all patients undergoing primary superficial parotidectomy for benign pathology with abdominal free fat grafting between June 2007 and December 2010, performed by a single surgeon. A survey was also distributed to otorhinolaryngology consultants across Australia to assess current practice. RESULTS: Twenty-eight patients were included. No patient had clinical symptoms of Frey's syndrome. Seventy-five per cent of patients were completely satisfied with their aesthetic outcome, 18 per cent scored 4/5 and the remaining 7 per cent (2 patients) scored 3/5. The survey revealed that 79 per cent of respondents did not use interpositional grafts. CONCLUSION: Abdominal free fat is ideal for grafting as it is an effective, safe, simple, accessible, fast and inexpensive method of providing an interpositional graft.

Calcium- and ROS-mediated defence responses in BY2 tobacco cells by nonpathogenic Streptomyces sp.

AIMS: The early molecular events underlying the elicitation of plant defence reactions by Gram-positive bacteria are relatively unknown. In plants, calcium and reactive oxygen species are commonly involved as cellular messengers of a wide range of biotic stimuli from pathogenic to symbiotic bacteria. In the present work, we checked whether nonpathogenic Streptomyces sp. strains could induce early signalling events leading to defence responses in BY2 tobacco cell suspensions. METHODS AND RESULTS: We have demonstrated that nonpathogenic Streptomyces sp. OE7 strain induced a cytosolic Ca(2+) increase and a biphasic oxidative burst in the upstream signalling events, leading to defence responses in BY2 tobacco cell suspensions. Streptomyces sp. OE7 also elicited delayed intracellular free scopoletin production and programmed cell death. In agreement with scopoletin production, OE7 induced accumulation of PAL transcripts and increased accumulation of transcripts of EREBP1 and AOX genes that are known to be regulated by the jasmonate/ethylene pathway. Transcript levels of PR1b and NIMIN2α, both salicylic acid pathway-linked genes, were not modified. Moreover, Streptomyces sp. OE7 culture filtrates could reduce Pectobacterium carotovorum- and Pectobacterium atrosepticum-induced death of BY2 cells and soft rot on potato slices. CONCLUSIONS: New insights are thus provided into the interaction mechanisms between Streptomyces sp. and plants; Streptomyces sp. could be sensed by plant cells, and through cytosolic Ca(2+) changes and the generation of reactive oxygen species, defence responses were induced. SIGNIFICANCE AND IMPACT OF THE STUDY: These induced defence responses appeared to participate in attenuating Pectobacterium-induced diseases in plants. Thus, Streptomyces sp. OE7 could be a biocontrol agent against Pectobacterium sp.

Occurrence OF Pectobacterium carotovorum strains isolated from potato soft rot in Morocco.

Pectobacterium carotovorum subsp. carotovorum, Pectobacterium astrosepticum and Pectobacterium chrysanthemi are the soft rot tuber of potatoes pathogens (Solanum tuberosum). The aim of this study was to determine the occurrence of these pathogens in Moroccan regions producing potatoes. Fifty three isolates of Pectobacterium were isolated on medium Crystal Violet Pectate. The comparison of their bacteriological characteristics with standard strains allowed us to conclude that all the isolates belonged to the Pectobacterium. With regard to phenotype characteristics, the variability that was found included 32 typical Pectobacetrium carotovorum subsp. carotovorum, 3 typical Pectobacterium atrosepticum, and 18 atypical Pectobacterium carotovorum subsp. carotovorum. Three strains of the atypical group; showed that the biochemical properties overlap among the Pectobacterium carotovorum and Pectobacterium chrysanthemi. These data were needed molecular characterization. However, the PCR amplification of total genomic DNA of 53 isolates with the two primers Y1/Y2 and P143/P145 yielded an amplified fragment of the expected size (434 bp) only with Y1/Y2, indicated that all the isolates collected and tested belonged to the Pectobacterium carotovorum species. On the basis the pathogenicity tests, these strains revealed that they were pectinolytic, and showed differences in aggressiveness against potato and leaves of tobacco.

Anaesthesia for microlaryngeal and laser laryngeal surgery: impact of subglottic jet ventilation.

OBJECTIVE: Over the past 20 years, jet ventilation techniques have been developed to enable safe and controlled microlaryngoscopy and the accurate treatment of laryngeal pathology. This study examined how advances in jet ventilation tube design have facilitated safe endolaryngeal surgery. STUDY DESIGN: The study documented the development and use of the Jockjet subglottic jet ventilation tube system at the Prince of Wales Hospital, Sydney. The new system consisted of two components: a Teflon tube with an outer diameter of 4 mm at the larynx, and a companion ventilator. The facility for end-tidal carbon dioxide and distal airways pressure monitoring was incorporated via dedicated channels. The Venturi jet was produced via a covered tip to prevent trauma to the tracheal mucosa. SETTING: The Prince of Wales and Sydney Children's Hospitals, incorporated with The University of New South Wales. PATIENTS: From June 2002 to March 2008 inclusive, 1000 consecutive patients underwent microlaryngeal surgery at this institution. Subglottic jet ventilation, via the Jockjet tube, was employed for 332 patients. MAIN OUTCOME MEASURES: Anaesthetic safety and intra-operative surgical access. RESULTS: In all the 332 patients observed, surgical access was optimised and no adverse anaesthetic outcomes were encountered. CONCLUSION: Subglottic jet ventilation facilitates safe airway management during microlaryngeal and laser laryngeal surgery.

In vitro and in vivo antagonism of actinomycetes isolated from Moroccan rhizospherical soils against Sclerotium rolfsii: a causal agent of root rot on sugar beet (Beta vulgaris L.).

AIMS: To evaluate the ability of the isolated actinomycetes to inhibit in vitro plant pathogenic fungi and the efficacy of promising antagonistic isolates to reduce in vivo the incidence of root rot induced by Sclerotium rolfsii on sugar beet. METHODS AND RESULTS: Actinomycetes isolated from rhizosphere soil of sugar beet were screened for antagonistic activity against a number of plant pathogens, including S. rolfsii. Ten actinomycetes out of 195 screened in vitro were strongly inhibitory to S. rolfsii. These isolates were subsequently tested for their ability to inhibit sclerotial germination and hyphal growth of S. roflsii. The most important inhibitions were obtained by the culture filtrate from the isolates J-2 and B-11, including 100% inhibition of sclerotial germination and 80% inhibition of hyphal growth. These two isolates (J-2 and B-11) were then screened for their ability to protect sugar beet against infection of S. rolfsii induced root rot in a pot trial. The treatment of S. rolfsii infested soil with a biomass and culture filtrate mixture of the selected antagonists reduced significantly (P < or = 0.05) the incidence of root rot on sugar beet. Isolate J-2 was most effective and allowed a high fresh weight of sugar beet roots to be obtained. Both antagonists J-2 and B-11 were classified as belonging to the genus Streptomyces species through morphological and chemical characteristics as well as 16S rDNA analysis. CONCLUSION: Streptomyces isolates J-2 and B-11 showed a potential for controlling root rot on sugar beet and could be useful in integrated control against diverse soil borne plant pathogens. SIGNIFICANCE AND IMPACT OF THE STUDY: This investigation showed the role, which actinomycete bacteria can play to control root rot caused by S. rolfsii, in the objective to reduce treatments with chemical fungicides.

An early Ca2+ influx is a prerequisite to thaxtomin A-induced cell death in Arabidopsis thaliana cells.

The pathogenicity of various Streptomyces scabies isolates involved in potato scab disease was correlated with the production of thaxtomin A. Since calcium is known as an essential second messenger associated with pathogen-induced plant responses and cell death, it was investigated whether thaxtomin A could induce a Ca2+ influx related to cell death and to other putative plant responses using Arabidopsis thaliana suspension cells, which is a convenient model to study plant-microbe interactions. A. thaliana cells were treated with micromolar concentrations of thaxtomin A. Cell death was quantified and ion flux variations were analysed from electrophysiological measurements with the apoaequorin Ca2+ reporter protein and by external pH measurement. Involvement of anion and calcium channels in signal transduction leading to programmed cell death was determined by using specific inhibitors. These data suggest that this toxin induces a rapid Ca2+ influx and cell death in A. thaliana cell suspensions. Moreover, these data provide strong evidence that the Ca2+ influx induced by thaxtomin A is necessary to achieve this cell death and is a prerequisite to early thaxtomin A-induced responses: anion current increase, alkalization of the external medium, and the expression of PAL1 coding for a key enzyme of the phenylpropanoid pathway.

Combined approach tympanoplasty for cholesteatoma: impact of middle-ear endoscopy.

OBJECTIVE: The aims of this study were (1) to explore whether the experience at the Radcliffe Infirmary (Oxford, UK) supported the use of combined approach tympanoplasty for cholesteatoma, by determining the rate of disease at subsequent surgery, and (2) to assess whether this rate differed from findings reported elsewhere in the literature, possibly due to the effect of using an oto-endoscope. STUDY DESIGN: Retrospective case review, with data entered prospectively for operations performed by a single surgeon. SETTING: Tertiary referral hospital. PATIENTS: Between January 1998 and December 2004 inclusive, 66 patients underwent 68 primary procedures, with data available for all 'second looks'. INTERVENTIONS: Diagnostic and therapeutic operations for cholesteatoma were performed. MAIN OUTCOME MEASURES: All patients in this study attended follow up and underwent a second look operation, during which the rate of residual and recurrent cholesteatoma was determined. An oto-endoscope was used at all primary and subsequent surgery. RESULTS: The mean interval between the first and second combined approach tympanoplasty procedures was 16 months, and that between the second and third such procedures was 19 months (10 patients). One patient underwent a fourth combined approach tympanoplasty procedure, 17 months after a third such procedure. The rate of cholesteatoma at second combined approach tympanoplasty was 20.6 per cent (14/68); this was judged to be residual in 10 ears (14.7 per cent) and to be recurrent, with the redevelopment of retraction pockets, in four ears (5.9 per cent). The rate of cholesteatoma at third combined approach tympanoplasty was 20 per cent (two of 10); of these two, one patient had a small pearl in the middle ear removed with the aid of a potassium titanyl phosphate laser. There was no disease present in one patient at a fourth combined approach tympanoplasty. Only four patients required a modified radical mastoidectomy. CONCLUSION: Cholesteatoma remains a disease with significant morbidity. Endoscope-assisted surgery may decrease the morbidity of second look surgery and may improve the clearance of disease in appropriately selected patients.

Bacterial biofilm adherence to middle-ear ventilation tubes: scanning electron micrograph images and literature review.

INTRODUCTION: The organisms that cause many device-related and other chronic infections actually grow in biofilms in or on these devices. We sought to examine the role of biofilm formation in chronic middle-ear ventilation tube infection. CASE REPORT: Scanning electron micrograph images are presented which demonstrate biofilm on a middle-ear ventilation tube removed from a five-year-old child's chronically discharging ear. A review of the relevant international literature explores the role of biofilms in chronic infection and discusses potential intervention strategies. CONCLUSION: Biofilms may be responsible for chronic middle-ear ventilation tube infection that resists treatment with conventional antibiotics.

Coronary artery bypass grafting (CABG) after initially successful percutaneous transluminal coronary angioplasty (PTCA): a review of 17 years experience.

OBJECTIVE: Patients who undergo successful percutaneous transluminal coronary angioplasty (PTCA) may subsequently require operative myocardial revascularization. This review examines whether prior successful PTCA alters outcomes following subsequent coronary artery bypass grafting (CABG). The costs of interventional cardiology procedures and definitive surgery were also examined. METHODS: From January 1981 through December 1997, 361 patients underwent CABG following initially successful PTCA (interval group). This group was compared with 11,909 patients who underwent CABG as the primary intervention for coronary artery disease (control group). RESULTS: The average time interval to CABG following initial PTCA was 13.7 months. The post-CABG myocardial infarction rate was 4% for patients in the interval group and 3% for patients in the control group. The 30-day mortality was similar for both patient groups (2%). For the interval group, the average cost of total interventional management was 24,220 dollars per patient. This included average costs of 13,873 dollars for CABG and 10,347 dollars for all preoperative interventional cardiology procedures. CONCLUSION: There is little doubt that PTCA procedures may provide successful myocardial revascularization. However, these procedures often need to be repeated over time and may serve only to delay coronary surgery, at substantial financial and personal cost.

Intraoperative quick parathyroid hormone versus same-day parathyroid hormone testing for minimally invasive parathyroidectomy: a cost-effectiveness study.

BACKGROUND: Intraoperative quick parathyroid hormone (QPTH) measurement is claimed to eliminate failures during minimally invasive parathyroidectomy. The cost-effectiveness of QPTH (ie, true cost of avoiding a failed operation) needs careful evaluation. METHODS: In 92 consecutive patients who underwent minimally invasive parathyroidectomy via a small lateral incision, QPTH was estimated preoperatively and at 5, 10, and 15 minutes postparathyroidectomy. QPTH results were subsequently compared with the procedure outcome. Cost-effectiveness analysis was performed for 3 subsequent theoretical management strategies: QPTH not performed, QPTH results available intraoperatively, and parathyroid hormone and serum calcium levels measured routinely with results made available the same day. RESULTS: With criteria for cure being a decrease in the QPTH measurement to less than 50% of preoperative levels and to within normal range, QPTH predictions were true positive in 78 patients; false-negative in 7; false-positive in 1; and true negative in 2. The true cost of using QPTH measurement to avoid a failed operation was 19,801.19 US dollars, with 7 patients undergoing unnecessary conversion. Routine same-day parathyroid hormone and calcium measurements significantly reduced this to 624.73 dollars. Sensitivity analysis with varying cost assumptions demonstrated cost-effectiveness analysis to be robust. CONCLUSIONS: The fact that 97% of patients will be cured regardless of QPTH testing combined with its false-negative rates significantly reduces the cost-effectiveness of the test when compared with same-day parathyroid hormone testing.

Bioactive compounds from Pseudanabaena species (Cyanobacteria).

Bioactive products of the multicellular filamentous benthic cyanobacterium, Pseudanabaena species, isolated from wastewater stabilization ponds at Marrakech, were tested against some pathogenic micro-organisms. Extracellular and intracellular products released by this blue-green alga in the stationary, growth phase, reduced the survival of Escherichia coli, Salmonella sp., Staphylococcus aureus and Candida albicans, and stimulated the growth of non-O1 V. cholerae, whereas no significant effect was noted on the growth of Candida tropicalis. Intracellular substances (methanolic extract) had a stronger inhibitory effect on these micro-organisms than that produced by extracellular substances. These antibacterial and antifungal substances may have a pharmacological value. They may have an important ecological effect on the composition of the bacterial community in Marrakech stabilization ponds when blooms of Pseudanabaena species occurred in this sewage treatment ecosystem during hot periods.

Ludwig's angina: report of a case and review of management issues.

Ludwig's angina, although uncommon, remains a potentially life-threatening condition because of the risk of impending airway obstruction. Effective treatment is based on early recognition of the clinical process, with the appropriate use of parenteral antibiotics, airway protection techniques, and formal surgical drainage of the infection. We present a case of Ludwig's angina together with a brief review of the relevant literature.

Combined endovascular and open surgery for four-vessel cerebrovascular occlusive disease.

PURPOSE: To report a case of bilateral simultaneous percutaneous transluminal angioplasty and stenting of the intracranial vertebral arteries prior to staged bilateral carotid endarterectomy. CASE REPORT: A 68-year-old man presented with a 3-month history of recurrent, intermittent left-sided weakness and diplopia. Imaging defined bilateral 80% to 99% internal carotid artery stenoses and >90% stenoses of both distal vertebral arteries at the level of the foramen magnum. Bilateral intracranial vertebral artery stenting was performed, followed by staged carotid endarterectomies. No complications occurred, and the patient recovered uneventfully from all 3 procedures. He remains symptom- and event-free 20 months later. CONCLUSIONS: Our initial success in this case indicates a role for percutaneous transluminal angioplasty and stenting as an alternative to open surgery for intracranial vertebral artery stenosis.

Angioplasty and stenting in the posterior cerebral circulation.

PURPOSE: To report initial experience with intracranial vertebral artery (VA) and basilar artery (BA) percutaneous transluminal angioplasty (PTA) and stenting. METHODS: Eleven patients (10 men; mean age 66 years, range 56-75) with intracranial 14 VA and 3 BA stenoses were managed from December 1997 through November 1999. All patients presented with vertebrobasilar ischemia (VBI) despite antiplatelet and anticoagulant therapy. Clinical presentations included visual disturbance (n = 8), dysarthria/dysphasia (n = 5), and vertigo (n = 5). RESULTS: Five patients underwent PTA only of 7 lesions with a mean preprocedural stenosis of 80% (range 50%-90%) that was reduced to 54% (range 30%-70%) after dilation. Six patients received 9 stents, 2 for VA dissections, 3 for tandem lesions, and 1 for a BA lesion. There were no embolic strokes. Patients were followed by clinical evaluation and personal or telephone interviews. Over a mean 18-month follow-up (range 12-35), 8 (73%) patients remained asymptomatic, while 3 (27%) had permanent deficits, 2 related to the procedure and 1 owing to distal disease CONCLUSIONS: Intracranial VA or BA angioplasty and stenting alleviated symptoms in patients with vertebrobasilar ischemia despite best medical management and may prevent stroke.

An epidemiological survey of methicillin-resistant Staphylococcus aureus in a tertiary referral hospital.

Over a 30-month period from July 1995 to December 1997, new detections of methicillin-resistant Staphylococcus aureus (MRSA) were prospectively studied in a tertiary referral hospital. The aims of the study were to determine the incidence of colonization of patients admitted to each of the hospital's 39 clinical units and ascertain where each patient had become colonized. Epidemiological information (time to detection, ward movement, admission to other hospitals, data on MRSA isolations in hospital wards) and phage typing were used by the hospital's infection control unit to make this determination. Routine containment procedures included cohorting, flagging and triclosan body washes. Surveillance cultures were collected infrequently. Patients known to be colonized with MRSA were excluded from orthopaedic and haematology wards. During the study period, 995 patients were found to be newly colonized. The incidence of colonization varied from nil to 72 per 1000 admissions, being highest in the main intensive care unit and in services which frequently used that unit. The incidence of colonization in elective orthopaedic surgery (< 1 per 1000) and haematology (3 per 1000) was very low. Determining the place where patients acquired MRSA was made difficult by the high frequency of endemic phage types and frequent patient transfer between wards. Epidemiological data suggested that the main intensive care unit and surgical wards nursing patients with colorectal, urological and vascular diseases were the places where most patients became colonized. MRSA was never acquired by patients nursed in wards which practised an exclusion policy towards patients known to be colonized with MRSA. Our data suggest that in tertiary referral hospitals, where MRSA is not only endemic but frequently imported from other hospitals, it is possible to establish areas where MRSA is never acquired.