The complex polyploid genome architecture of sugarcane.

Sugarcane, the world's most harvested crop by tonnage, has shaped global history, trade and geopolitics, and is currently responsible for 80% of sugar production worldwide1. While traditional sugarcane breeding methods have effectively generated cultivars adapted to new environments and pathogens, sugar yield improvements have recently plateaued2. The cessation of yield gains may be due to limited genetic diversity within breeding populations, long breeding cycles and the complexity of its genome, the latter preventing breeders from taking advantage of the recent explosion of whole-genome sequencing that has benefited many other crops. Thus, modern sugarcane hybrids are the last remaining major crop without a reference-quality genome. Here we take a major step towards advancing sugarcane biotechnology by generating a polyploid reference genome for R570, a typical modern cultivar derived from interspecific hybridization between the domesticated species (Saccharum officinarum) and the wild species (Saccharum spontaneum). In contrast to the existing single haplotype ('monoploid') representation of R570, our 8.7 billion base assembly contains a complete representation of unique DNA sequences across the approximately 12 chromosome copies in this polyploid genome. Using this highly contiguous genome assembly, we filled a previously unsized gap within an R570 physical genetic map to describe the likely causal genes underlying the single-copy Bru1 brown rust resistance locus. This polyploid genome assembly with fine-grain descriptions of genome architecture and molecular targets for biotechnology will help accelerate molecular and transgenic breeding and adaptation of sugarcane to future environmental conditions.

Field survey data on the effectiveness of agrometeorological services for smallholder farmers in Niger.

The dataset contains the answers of smallholder farmers to a semi-structured field survey and the 2020 yield plot measurements conducted in 8 municipalities of the Dosso and Tillabéri regions in Niger. It is a systematic sampling of about 320 questionnaires and 192 yield plot samples equally distributed in eight municipalities of intervention. The dataset contains several pieces of information about the uptake and the impacts of a tailored climate service (CS) produced by the National Meteorological Service (NMS) and disseminated through a network that involves Ministry of Agriculture extension services at the municipal level developed in the context of the AdaptatioN Au changement Climatique, prévention des catastrophes et Développement agrIcole pour la sécurité Alimentaire du Niger (ANADIA) Project. The material gathered by the survey gives a picture of the preferences of local farmers in the broadcasting of climate services information and their consequent strategical and tactical decisions in farm practices. Moreover, the survey investigates the preferences regarding the information that farmers would like to receive during the cropping season. Furthermore, the measurement of yield and its relation to the farmers' access to climate information and participation in training initiatives gives an indication of the impact of the CS on agricultural production in these regions. The dataset could benefit further studies and investigations about CSs for smallholder farmers in semi-arid regions. This article is a co-submission of the article: "Effectiveness of agrometeorological services for smallholder farmers: the case study in the regions of Dosso and Tillabéri in Niger" submitted to the journal Climate Services.

Cochlear implantation in chronic otitis media and previous middle ear surgery: 20 years of experience.

Cochlear implantation in the setting of chronic otitis media or previous middle ear surgery poses several problems for the surgeon: possible spread of infection to the cochlea and the subarachnoid spaces with consequent meningitis, risk of electrode array extrusion and possible recurrence of the original disease. Several surgical strategies have been proposed to overcome these problems. In the present study, clinical and functional results of cochlear implantation in 26 patients with chronic otitis media (8 cases) or previous middle ear surgery (18 cases) in the ear most suitable for implantation were retrospectively reviewed. Among the 8 patients with chronic otitis media, in 7 cases a subtotal petrosectomy associated with external auditory canal closure and mastoid and Eustachian tube obliteration was performed, while in the remaining patient cochlear implantation was done 6 months after a myringoplasty. The only complication observed was a reperforation of the tympanic membrane in this latter patient. Among the 18 patients with previous middle ear surgery, 2 had undergone intact canal wall tympanomastoidectomy and were implanted utilising the previous surgical approach. In the remaining 16 patients who had a radical cavity, an open technique was maintained in 3 cases; a cavity revision associated to external auditory canal closure, Eustachian tube and mastoid obliteration was performed in 12 patients, while in one case a middle cranial fossa approach was utilised. Two of the 3 patients in whom an open technique was maintained have experienced electrode array extrusion. The only complication observed in the remaining patients was the breakdown of the external auditory canal closure in one case. No problems were noted in patients who had undergone intact canal wall tympanomastoidectomy as well as in the subject implanted via the middle cranial fossa approach. All patients achieved and maintained good hearing performance over time. Subtotal petrosectomy associated with external auditory canal closure, Eustachian tube occlusion and mastoid obliteration is an effective procedure to facilitate cochlear implantation in presence of chronic otitis media. The open cavity technique offers the advantage of a close clinical examination, but may expose the patient to the risk of electrode array extrusion, mainly in the long-term period.

Heritability of arterial stiffness and carotid intima-media thickness: an Italian twin study.

BACKGROUND AND AIMS: Carotid intima-media thickness (IMT) and arterial stiffness parameters, including aortic augmentation index (AIx) and pulse wave velocity (PWV), are independent predictors of stroke and cardiovascular disease. Genetic effects on these traits were never explored in a Mediterranean country. The present study aims to quantify the contribution of genes, environment and age to carotid IMT and aortic Aix and PWV. METHODS AND RESULTS: The twin design was used. A total of 348 adult twins from the Italian Twin Register underwent measurements of carotid IMT and aortic PWV and AIx in three university hospitals located in Rome, Padua and Perugia. Carotid IMT was measured by B-mode ultrasound, aortic PWV and AIx by Arteriograph. Genetic modelling was performed to decompose total variance of traits into genetic, shared and unshared environmental and age components. For each phenotype, the best-fitting model included additive genetic, unshared environmental and age effects. For IMT, heritability was 0.32 (95% confidence interval (CI): 0.25-0.38), unshared environmental component was 0.25 (0.18-0.32) and age contribution was 0.44 (0.39-0.49). For AIx and PWV, heritabilities were 0.42 (0.29-0.55) and 0.49 (0.35-0.62), unshared environmental components were 0.31 (0.22-0.44) and 0.37 (0.26-0.51) and age contributions were 0.27 (0.16-0.39) and 0.14 (0.06-0.24), respectively. CONCLUSION: This study shows substantial genetic and unshared environmental influences on carotid intima-media thickness and arterial stiffness and confirms the relevant role of age in the aetiology of these traits. Further support is provided for prevention and health promotion strategies based on modifiable factors.

A congenital tympanic membrane cholesteatoma (CTMC) in the adult: a case report.

OBJECTIVE: We present an additional very rare case of a congenital tympanic membrane cholesteatoma (CTMC) in the adult. METHOD: Case report and literature review of CTMC. CASE REPORT: A 54-year old man was referred to us by his primary care physician who noted a white mass on the right tympanic membrane without prior history of otorrhea, tympanic perforations or previous otologic procedures. The pearl was about 5 mm diameter, centered on the umbo of a normal tympanic membrane (TM). The audiogram and the tympanogram was absolutely normal. CT confirmed a soft round shape tissue mass, located in the centre of the TM near umbo. The mass protruded both in the auditory canal and in the middle ear space, touching the malleus extremity, without any relationship with medial wall of the cavum tympani. A surgical excision was performed using a "minimal" retroauricolar transcanalar approach: the CTMC was located into the thickness of the TM, between epidermic and mucous layers. The ossicular chain was preserved intact. A partial myringoplasty (underlay technique) using a temporalis fascia graft was necessary. Histopathology confirmed a cystic cholesteatoma. After two months and one year follow-up, otoendoscopy showed a well-healed TM with a preserved normal audiogram and tympanogram. DISCUSSION: This exceptional (probably the first reported) case showed the possible localization of the CC in the TM, also in the adult. Criteria for classification of a TM cholesteatoma as congenital and possible pathogenetic mechanisms are discussed.

Diagnostic accuracy of colour Doppler ultrasonography, CT angiography and blood-pool-enhanced MR angiography in assessing carotid stenosis: a comparative study with DSA in 170 patients.

PURPOSE: This study was undertaken to prospectively evaluate the diagnostic performance of colour Doppler ultrasonography (CDUS), first-pass (FP) and steady-state (SS) contrast-enhanced magnetic resonance angiography (MRA) and computed tomography angiography (CTA) of the carotid arteries using digital subtraction angiography (DSA) as the reference standard. MATERIALS AND METHODS: A total of 170 patients with previous cerebrovascular events and suspected carotid artery stenoses underwent CDUS, blood-pool MRA, CTA and DSA. Accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated for CDUS, FP MRA, SS MRA and CTA. The McNemar and Wilcoxon tests and receiver operating characteristic (ROC) curve analysis were used to determine significant differences (p<0.05) between the diagnostic performances of the four modalities, and the degree of stenosis was compared using linear regression. RESULTS: A total of 336 carotid bifurcations were studied. The area under the curve (AUC) for degree of stenosis was: CDUS 0.85±0.02, FP MRA 0.982±0.005, SS MRA 0.994±0.002 and CTA 0.997±0.001. AUC analysis showed no statistically significant difference between CTA and MRA (p=0.0174) and a statistically significant difference between CDUS and the other techniques (p<0.001). Plaque morphology analysis showed no significant difference between CTA and SS MRA; a significant difference was seen between CTA and SS MRA versus FP MRA (p=0.04) and CDUS (p=0.038). Plaque ulceration analysis showed a statistically significant difference between MRA and CTA (0.04< p<0.046) versus CDUS (p=0.019). CONCLUSIONS: CTA is the most accurate technique for evaluating carotid stenoses, with a slightly better performance than MRA (97% vs. 95% for SS MRA and 92% for FP MRA) and a greater accuracy than CDUS (97% vs. 76%). Blood-pool contrast-enhanced SS sequences offer improved evaluation of degree of stenosis and plaque morphology with accuracy substantially identical to CTA.

Malignant tumours of the small intestine: a review of histopathology, multidetector CT and MRI aspects.

Small bowel neoplasms, including adenocarcinoma, carcinoid tumour, lymphoma and gastrointestinal stromal tumours, represent a small percentage of gastrointestinal cancers, yet are among those with the poorest prognosis compared with other gastrointestinal malignancies. Unclear clinical scenarios and difficult radiological diagnosis often delay treatment with negative effects on patient survival. Recently, multidetector CT (MDCT) and MRI have been introduced as feasible and accurate diagnostic techniques for the identification and staging of small bowel neoplasms. These techniques are gradually replacing conventional barium radiography as the tool of choice. However, the inherent technical and physiological challenges of small bowel imaging require a familiarity with patient preparation and scan protocols. Adequate knowledge of the histopathology and natural evolution of small bowel neoplasms is also important for differential diagnosis. The aim of this article is to review MDCT and MRI protocols for the evaluation of small bowel tumours and to provide a concise yet comprehensive guide to the most relevant imaging features relative to histopathology.

Preliminary experience with MRA in evaluating the degree of carotid stenosis and plaque morphology using high-resolution sequences after gadofosveset trisodium (Vasovist) administration: comparison with CTA and DSA.

PURPOSE: The authors performed a preliminary study with blood-pool contrast-enhanced magnetic resonance angiography (MRA) in evaluating the degree of carotid artery stenosis and plaque morphology, comparing the diagnostic performance of first-pass (FP) and steady-state (SS) acquisitions with 64-slice computed tomography angiography (CTA) and using digital subtraction angiography (DSA) as the reference standard. MATERIALS AND METHODS: Twenty patients with >or=50% carotid artery stenosis at Doppler sonography underwent blood-pool contrast-enhanced MRA, CTA and DSA. Two independent radiologists evaluated MRA and CTA examinations to assess the degree of stenosis and characterise plaque morphology. Accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated for FP, SS and CTA. The McNemar and Wilcoxon tests were used to determine significant differences (p<0.05) between the diagnostic performance of the three modalities. RESULTS: Forty carotid bifurcations were studied. For stenosis grading, accuracy, sensitivity, specificity, PPV and NPV were 90%, 89%, 90%, 89% and 90%, respectively, at FP; 95%, 95%, 95%, 95% and 95%, respectively, at SS; and 97.5%, 95%, 100%, 100% and 95%, respectively, at CTA. SS and CTA were superior to FP for evaluating the degree of stenosis (p<0.05). For evaluating plaque morphology, accuracy, sensitivity, specificity, PPV and NPV were 87.5%, 89%, 86%, 85% and 90%, respectively, at FP; 97.5%, 100%, 95%, 95% and 100%, respectively, at SS; and 100%, 100%, 100%, 100% and 100%, respectively, at CTA. There were no significant differences between FP, SS and CTA for plaque assessment (p>0.05). CONCLUSIONS: Blood-pool contrast-enhanced MRA with SS sequences allow improved diagnostic evaluation of the degree of carotid stenosis and plaque morphology compared with FP and is substantially equal to CTA and DSA.

Diagnostic performance of 64-MDCT and 1.5-T MRI with high-resolution sequences in the T staging of gastric cancer: a comparative analysis with histopathology.

PURPOSE: This study was undertaken to compare the accuracy of magnetic resonance (MR) imaging and 64-slice multidetector computed tomography (64-MDCT) in the T staging of gastric carcinoma in comparison with histopathology. MATERIALS AND METHODS: Forty patients with an endoscopic diagnosis of gastric carcinoma underwent preoperative MR imaging and 64-MDCT, both of which were performed after i.v. injection of scopolamine and water distension of the stomach. In the MR imaging protocol, we acquired T2-weighted turbo spin-echo (TSE) sequences, true fast imaging steady-state free precession (true-FISP) and gadolinium-enhanced T1-weighted volumetric interpolated breath-hold examination (VIBE) 3D sequences. Contrastenhanced CT scans were obtained in the arterial and venous phases. Two groups of radiologists independently reviewed the MR and 64-MDCT images. The results were compared with pathology findings. RESULTS: In the evaluation of T stage, 64-MDCT had 82.5% and MR imaging had 80% sensitivity. Accuracy of MR imaging was slightly higher than that of 64-MDCT in identifying T1 lesions (50% vs 37.5%), whereas the accuracy of 64-MDCT was higher in differentiating T2 lesions (81.2% vs 68.7%). The accuracy of MR imaging and 64-MDCT did not differ significantly in the evaluation of T3-T4 lesions (p>0.05). Understaging was observed in 20% of cases with MR imaging and in 17.5% with 64-MDCT. CONCLUSIONS: MR imaging and 64-MDCT accuracy levels did not differ in advanced stages of disease, whereas MR imaging was superior in identifying early stages of gastric cancer and can be considered a valid alternative to MDCT in clinical practice.

Chemical composition and cytotoxic, mutagenic and genotoxic activities of the essential oil from Pipergaudichaudianum Kunth leaves.

We have investigated the chemical composition of Piper gaudichaudianum essential oil, as well as its cytotoxic, mutagenic and genotoxic effects in V79 cells. The chemical analyses showed that the major compounds are (E)-nerolidol (22.4%), alpha-humulene (16.5%), (E)-caryophyllene (8.9%) and bicyclogermacrene (7.4%). Dose-dependent cytotoxic effects were observed in V79 cells treated with essential oil by using clonal survival, 3-(4,5-dimethylthiazole-2-yl)-2,5-biphenyl tetrazolium bromide reduction assay (MTT) and trypan blue exclusion assay (TB), and a significant decrease in survival was observed at concentrations of 0.5 microg/mL and higher. The P. gaudichaudianum essential oil treatment caused DNA strand breaks in V79 cells at concentrations up to 2 microg/mL, as detected by the alkaline comet assay, but did not induce double-strand breaks, as verified by neutral comet assay. It induced a significant increase in the frequency of micronucleated cells at 4, 6 and 10 microg/mL. Moreover, P. gaudichaudianum essential oil significantly increased lipid peroxidation at doses of 0.5 microg/mL and higher, suggesting that the observed oxidant potential can be responsible, at least in part, for its cytotoxic and genotoxic effects.

Optimisation of a high-resolution whole-body MR angiography protocol with parallel imaging and biphasic administration of a single bolus of Gd-BOPTA: preliminary experience in the systemic evaluation of atherosclerotic burden in patients referred for endovascular procedures.

PURPOSE: This study was performed to validate a high-resolution whole-body magnetic resonance angiography (MRA) protocol with parallel imaging and biphasic administration of a single bolus of contrast agent in the preliminary assessment of systemic atherosclerotic burden in patients referred for endovascular procedures. MATERIALS AND METHODS: Forty patients referred for endovascular treatment of atherosclerotic disease of the carotid arteries (n=23), peripheral vessels (n=14) or aorta (n=3) on the basis of previous clinical and diagnostic examinations underwent high-resolution whole-body MRA at 1.5 T with 3D spoiled gradient recalled echo (GRE) sequences, featuring parallel imaging acquisition technique with x2 acceleration factor. Sixty-eight surface coil elements and a four-station imaging protocol were employed. Biphasic intravenous administration of a paramagnetic contrast agent [gadolinium benzyloxyproprionic-tetraacetic acid (Gd-BOPTA)] was performed with the following protocol: 10 ml at a speed of 1 ml/s followed by further 10 ml at a speed of 0.5 ml/s. For image analysis, the arterial system was divided into 42 segments for evaluation. The presence or absence of atherosclerotic lesions was evaluated by two observers in consensus; segments were classified as having clinically significant disease (>or=50% stenosis or an aneurysmal dilatation) or no significant disease (<50% stenosis). The presence of stenoocclusive disease, determined at all segments, was compared with findings on digital subtraction angiography (DSA), which were interpreted by a third independent reader. Sensitivity, specificity and concordance of whole-body MRA findings with DSA were calculated, and receiver operating characteristic (ROC) analysis was performed for all vascular territories. RESULTS: A total of 1,680 arterial segments was evaluated; 138 (8.3%) were affected by atherosclerotic alterations. Carotid lesions were confirmed in 23 patients (34 segments), involvement of peripheral vessels in 14 (57 segments) and abdominal aneurysms in three. Sensitivity and specificity of whole-body MRA were, respectively, 95%-97% for head and neck vessels, 100%-100% for thoracoabdominal vessels, 98%-97% for thigh vessels and 84%-88% for calf vessels; concordance with the DSA findings was significant (p<0.05). Subclinical atherosclerotic lesions were evidenced in 25 patients, involving carotid arteries (12 segments), peripheral vessels (21 segments) and abdominal aorta (one segment). All these lesions were confirmed by a second modality, and ten of these patients required further care. CONCLUSIONS: High-resolution whole-body MRA with Gd-BOPTA may be considered a reliable modality for imaging systemic atherosclerosis in candidates for endovascular procedures. The subclinical detection of the total atherosclerotic burden has potential implications for secondary care in this population.

64-MDCT imaging of the coronary arteries and systemic arterial vascular tree in a single examination: optimisation of the scan protocol and contrast-agent administration.

PURPOSE: The aim of this study was to validate a 64-row multidetector computed tomography (64-MDCT) acquisition protocol with biphasic administration of contrast medium for comprehensive assessment of the coronary and systemic arterial tree in a single examination. MATERIALS AND METHODS: The scanning protocol comprised two acquisitions: an electrocardiograph (ECG)-gated scan at the level of the heart, followed by a total-body, low-dose scan of the systemic arterial circulation. Twenty patients were evaluated using two different strategies for contrast administration. In ten patients, the delay between the two acquisitions was set at 40 s, whereas in the remaining patients, it varied between 45 s and 65 s. For both strategies, the degree of systemic arterial opacification and the attenuation gradient between arterial and venous structures were quantitatively assessed at six extracoronary locations. Two observers evaluated in consensus the presence or absence of atherosclerosis and the degree of stenosis of arterial segments. RESULTS: Three hundred coronary segments were analysed. Arterial-wall changes were depicted in 155 (51%) segments, and in 35 (23%), the degree of stenosis was > 50%. Of the 640 extracoronary arterial segments, 250 (39%) presented atherosclerotic wall alterations, in 50 (20%), the degree of stenosis was > 50% and five were affected by aneurysmal dilatation. The magnitude of arterial opacification values and attenuation gradients between arterial and venous structures were significantly higher in patients scanned with the 40-s fixed-delay strategy. CONCLUSIONS: Whole-body CT angiography with biphasic administration of contrast agent and fixed scan delay has been shown to be a feasible and reproducible technique. Comprehensive data on the global atherosclerotic burden potentially offer important therapeutic options for subclinical, high-risk segments.

Imaging the whole body atherosclerosis: high resolution magnetic resonance angiography using blood-pool agent. Initial clinical experience.

AIM: Recently whole-body 3D MR angiography (MRA) with blood-pool contrast agent has become available. The purpose of this study was to introduce and evaluate this technique to demonstrate arterial steno-occlusive involvement in systemic atherosclerosis and to compare blood-pool enhanced MRA results with those of CT angiography (CTA) as reference modality. METHODS: Twenty patients with clinically and US documented carotid occlusive disease underwent whole-body MRA on a 1.5 T scanner and CTA on a 64-MDCT unit. Ten milliliters of a blood-pool agent (MS-235 Gadofosveset Trisodium, VASOVIST, Schering, Berlin, Germany) were administered intravenously and four 3-D MRA stations were acquired successively through automatic table moving. Images were reviewed by two observers. Overall image quality of each arterial segment was assessed and rated for both MRA and CTA examinations; MRA sensitivity, MRA specificity interobserver and intermodality agreement were calculated. RESULTS: Whole-body MRA with blood-pool contrast agent was well tolerated by all patients. It yielded a detailed display of the arterial system with a short examination time. In 14 out of 20 patients there was extensive involvement of the arterial bed by steno-occlusive atherosclerotic disease; for the identification and characterization of vessel damage in the various vascular districts MRA sensitivity was 92-100%, MRA specificity was 95-100%; in 2 cases MRA underestimated the degree of peripheral vessel stenosis. Interobserver agreement calculated with K value was 0.63, intermodality agreement with CTA was 93% (P<0.01). CONCLUSION: The whole-body MRA technique is a valuable tool for comprehensive evaluation of arterial steno-occlusive involvement in systemic arterial atherosclerosis; there is a good agreement between blood-pool enhanced MRA results and CTA, used as modality of reference.

Subjective tinnitus, temporomandibular joint dysfunction, and serotonin modulation of neural plasticity: causal or casual triad?

Tinnitus and temporomandibular joint dysfunction (TMJD) are among the most common complaints encountered by physicians. Though the relationship between tinnitus and TMJD has attracted great interest during the past several years, theories attempting to explain this association are still few and inconsistent. Conceivably, TMJD could irritate auricolo-temporal nerve (ATN), triggering a somatosensory pathway-induced disinhibition of dorsal cochlear nucleus (DCN) activity in the auditory pathway. In genetically-predisposed TMJD patients, signals from cronically stimulated DCNs activating specific cortical neuronal networks, could yield plastic neural changes resulting in tinnitus. Based on current evidence of serotoninergic modulation of neural activity and plasticity in sensory pathways, reduced serotoninergic tone could promote plastic changes underlying tinnitus through diminished filtering of incoming signals. Therefore, the early establishment of specific treatments aimed at improving TMJD and/or boosting serotoninergic activity may be required to prevent the creation of 'tinnitus memory circuits'.

Hearing results in stapes surgery using two different prosthesis.

AIM OF THE STUDY: Evaluation of hearing results after implantation of a fluoroplastic-platinum piston (FP) and of a titanium piston (T) with a shaft diameter of respectively 0.6 mm and 0.4 mm, in cases of otosclerosis requiring stapedotomy. MATERIAL AND METHODS: Pre-operative and post-operative hearing results obtained after primary stapedotomy by implantation of 30 FP and 30 T performed by the same expert author (C.Z.) were reviewed. In each patient we evaluated pre- and post-operative auditory thresholds, as recommended. RESULTS: All patients of both groups showed a significant air-bone gap (ABG) improvement for all frequencies after surgery ( P < 0. 001). Post-operative ABG comparison between the two groups showed a better ABG for lower frequencies in the FP group and for higher frequencies in the T group, but the difference was not significant. No post-operative complications, including sensorineural hearing loss, were found. Bone conduction improvement was better in the FP group than in the T one and this difference was statistically significant at 1000 and 2000 Hz. There was no statistically significant difference in the post-operative outcomes between the two prosthesis. Better results of FP for lower frequencies suggest that an increase in diameter of the prosthesis results in a greater improvement in the hearing threshold at low frequencies, while a decrease of diameter results in a greater improvement in the hearing threshold at high frequencies, as indicated by previous international studies. CONCLUSION: Our data shows that titanium piston is a as good as fluoroplastic piston in stapes surgery for otosclerosis.

Monitoring biogenic volatile compounds emitted by Eucalyptus citriodora using SPME.

A procedure to monitor BVOC emitted by living plants using SPME technique is presented. For this purpose, a glass sampling chamber was designed. This device was employed for the characterization of biogenic volatile compounds emitted by leaves of Eucalyptus citriodora. After extraction with SPME fibers coated with PDMS/ DVB, it was possible to identify or detect 33 compounds emitted by this plant. A semiquantitative approach was applied to monitor the behavior of the emitted BVOC during 9 days. Circadian profiles of the variation in the concentration of isoprene were plotted. Using diffusion-based SPME quantitation, a recently introduced analytical approach, with extraction times as short as 15 s, it was possible to quantify subparts-per-billion amounts of isoprene emitted by this plant.

[Long-term audition results in patients with chronic endolymphatic hydrops after selective vestibular neurotomy and endolymphatic sac surgery]. / Risultati uditivi a lungo termine in pazienti con idrope endolinfatica cronica dopo neurotomia vestibolare selettiva e trattamento del sacco endolinfatico.

The purpose of the present study was to evaluate the long-term auditory results in the ears of patients suffering from unilateral Ménière's disease (Md) who had undergone retrolabyrinthine vestibular neurotomy (RVN) associated with endolymphatic sac (ES) surgery. Retrospective evaluation was performed on 45 patients with unilateral Md who had undergone RVN between 1982-1997. All patients had previously been treated with medical therapy for at least 6 months without showing any response. The forms of ES surgery performed were as follows: simple ES decompression (ESD) in 15 patients, chronic endolymphatic mastoid shunt (EMS) using a sylastic sheet in 15 ears and ES exclusion (ESE) of the proximal section in the remaining 15 patients. Evaluation of the results was performed using the parameters indicated by the "Committee on Hearing and Equilibrium"--AAO-HNS 1995. Comparison of the average post-operative and preoperative PTAs revealed a worsening of 9.2 dB (sd: +/- 17.1) in the ESE group. This variation was statistically significant (p < 0.05). When the individual patients were evaluated, the PTA remained unchanged in 10 cases (67%) in the ESD group, in 13 (87%) in the EMS group and in 10 (67%) in the ESE group. In no case did hearing improve. Statistical analysis did not reveal any significant difference between the three groups of patients. Tinnitus, present prior to surgery in all patients, disappeared or improved in 6 patients (40%) in the ESD group, in 6 (40%) of the EMS group and in 5 (33%) of the ESE group. The differences between groups were not significant. The sensation of plugged ears, present prior to surgery in 11 patients in the ESD and EMS groups and in 13 patients in the ESE group disappeared or improved respectively in 9 (82%), 10 (91) and 11 (85%) of the patients. The 10 remaining patients who did not have the sensation of plugged ears prior to surgery did not refer its appearance after surgery. Again for this symptom the difference between groups was not significant. The results of this research would appear to indicate that in patients with Md, evolution of the hearing symptoms observed after RVN can be improved by applying an EMS. This finding must be validated in a larger sampling.

Closed tympanoplasty in cholesteatoma surgery: long-term (10 years) hearing results using cartilage ossiculoplasty.

The aim of this retrospective study was to evaluate the long-term hearing results of using costal cartilage prostheses in ossicular chain reconstruction procedures in subjects operated on for a middle ear cholesteatoma with an intact canal wall tympanoplasty. Thirty-six patients (four with bilateral disease) followed up for 10 years who underwent an ossiculoplasty with a cartilage prostheses between January 1987 and December 1989 constituted the population studied. All the subjects underwent a staged intact canal wall tympanoplasty with mastoidectomy. Ossiculoplasty with total or partial chondroprosthesis was performed during the second stage. The long-term outcome was evaluated in terms of hearing according to the guidelines of the Committee on Hearing and Equilibrium (1995), and in terms of complications (anatomical and functional). In 18 patients a partial cartilage ossicular replacement prosthesis (PORP) was used, while in 22 a total cartilage ossicular replacement prosthesis (TORP) was used. In the PORP group the mean preoperative air-bone gap (ABG) was 22.4 dB hearing level (HL); before the second stage the ABG was 37.9 dB HL, at 2 years it was 12.1 dB HL, at 5 years 15.3 dB HL and at 10 years 15.8 dB HL. In the TORP group the mean preoperative ABG was 31.6 dB HL; before the second stage the ABG was 41.1 dB HL, at 2 years it was 14.4 dB HL, at 5 years 17 dB HL and at 10 years 18.5 dB HL. In both groups the number of cases with a postoperative ABG of < 20 dB HL remained stable (P > 0.05) over time. The failure rate was 17.5%, but only in 5% of cases was a functional revision needed. No cases of extrusion of the prostheses were encountered. The use of a chondroprosthesis is associated with functional results similar to those obtained by other authors. The efficacy of the prostheses remains stable over time and is associated with a very low rate of complications and failures. In this series no extrusion occurred and in no case did an infectious disease develop after cartilage transplantation.