Field propagation-induced directionality of carrier-envelope phase-controlled photoemission from nanospheres.

Near-fields of non-resonantly laser-excited nanostructures enable strong localization of ultrashort light fields and have opened novel routes to fundamentally modify and control electronic strong-field processes. Harnessing spatiotemporally tunable near-fields for the steering of sub-cycle electron dynamics may enable ultrafast optoelectronic devices and unprecedented control in the generation of attosecond electron and photon pulses. Here we utilize unsupported sub-wavelength dielectric nanospheres to generate near-fields with adjustable structure and study the resulting strong-field dynamics via photoelectron imaging. We demonstrate field propagation-induced tunability of the emission direction of fast recollision electrons up to a regime, where nonlinear charge interaction effects become dominant in the acceleration process. Our analysis supports that the timing of the recollision process remains controllable with attosecond resolution by the carrier-envelope phase, indicating the possibility to expand near-field-mediated control far into the realm of high-field phenomena.

Behavioral and neurophysiological responses of an insect to changing ratios of constituents in host plant-derived volatile mixtures.

Ratios of compounds in host plant odors fluctuate with the phenological stage of the plant. In the present study, we investigated the effect of changing ratios of host plant volatile constituents on herbivore insect attraction and olfactory information processing. We tested a synthetic mixture of bioactive peach shoot volatiles with different concentrations of one of the mixture constituents, benzonitrile, on oriental fruit moth Cydia (=Grapholita) molesta females. Y-tube olfactometer bioassays showed that female attraction to the mixture was maintained while increasing the benzonitrile level up to 100 times. Further increases led to behaviorally ineffective mixtures. Then, we recorded odor-evoked neural activity patterns in the antennal lobes, the main olfactory center of the brain, using calcium imaging. Benzonitrile-containing mixtures elicited strong activation in two glomeruli, which were found to process mixture-related information in specific ways. Activation in one glomerulus directly paralleled behavioral effects of the different ratios tested whereas a deviating pattern was noted in the other glomerulus. Our results indicate that the ratio of constituents in a volatile mixture can be varied to a certain degree without reducing female attraction. Thus, volatile blends in nature might vary quantitatively within a certain range without affecting odor-guided host location. Neurophysiological results showed that the processing of mixture-related information inside the antennal lobes is not uniform across glomeruli. Thus, final processing of this information probably takes place in higher-order brain centers.

Middle ear adenomatous tumor: a not so rare glomus tympanicum-mimicking lesion.

BACKGROUND AND PURPOSE: Middle ear adenomatous tumors (MEAT) are rare tumors which can be begin or malignant and can present a neuroendocrine differentiation. Their radiological aspect is very similar to glomus tympanicum (GT) which are the most common tumoral lesions of the middle ear. We present several radiological and clinical findings that could help radiologists to accurately identify MEAT. MATERIAL AND METHODS: We retrospectively reviewed the radiological and clinical findings of three patients with MEAT and of eight patients with GT. Diagnostic was obtained after surgical resection in all cases. All patients had high resolution CT and MR of the middle ear associated with a subtracted digital carotid angiography. Tumor location, size, extension, signal intensity, and enhancement were analysed. From the medical records of the patients, clinical manifestations (hearing loss, tinnitus), evolution length and recurrences were noted. RESULTS: MEAT and GT appeared as tissular lesion with significant enhancement on CT and MR. A vascular blush was present on angiography in all cases of GT and absent from all cases of MEAT. A close relationship between the tumor and the Jacobson's nerve or its branches was identified in all cases of GT. Pulsatile tinnitus was present in all patients with GT and absent in all patients with MEAT. CONCLUSION: A middle ear tissular lesion clearly separated from the Jacobson nerve or its branches, showing significant enhancement after contrast medium injection but with a normal angiography, should make one suspicious for MEAT.

[Otosclerosis imaging: matching clinical and imaging data]. / Imagerie de l'otospongiose: confrontation clinique et imagerie.

Otosclerosis is a primitive osteodystrophia of the labyrinthine bone. Its diagnosis must be confirmed by a CT scan in order to eliminate the other causes that may lead to conductive hearing loss with an absence of stapedial reflex: fixation of the head of the malleus to the lateral wall of the tympanic cavity, absence of the long process of the incus or stapes, gusher syndrome, primary cholesteatoma, or tympanic facial nerve neuroma blocking the stapes. Particular problems in otosclerosis must be clarified: an extension to the round window (poor postoperative results), and extension to the tympanic cavity blocking the malleus and/or the incus, the labyrinthine lumen, or the internal auditory meatus (very rare). The position of the tympanic facial nerve canal and associated abnormalities must be assessed: stapedial artery, malformations of the ossicles and/or the labyrinth, and chronic otitis media. MRI is indicated in extension to the labyrinthine lumen, the internal auditory meatus, and in postoperative complications with labyrinthitis. MRI can also evaluate the active otosclerotic focus (gadolinium enhancement).

[Tonometric monitoring of the viability of free transplants of the jejunum and the stomach after total circulary pharyngolaryngectomy]. / Surveillance tonométrique de la vitalité des transplants libres de jéjunum et d'estomac après pharyngo-laryngectomie totale circulaire.

A prospective study concerning the tonometric viability supervision of 9 digestive free autografts after total pharyngolaryngectomy was conducted. This technic is based on the Henderson and Hasselbalch's equation which calculates the intramucosal pH (pHi) in the graft using a tonometric catheter. When the pHi is under 7.10, there is a graft ischemia. This invasive technique seems to be sensitive and specific provided that minimally rigorous measurement procedures are used. Late graft necrosis is the major limitation of the technique.

[Congenital cholesteatoma and associated ossicular malformations]. / Le cholestéatome congénital et les malformations ossiculaires associées.

15 cases of congenital cholesteatoma surgically treated from 1982 to 1992 are presented. Clinical diagnosis criteria, pathology, localisations and extensions to the middle ear are analyzed. Ossicular malformations were associated in one third of the patients of this series. These ossicular malformations underscore the congenital origin of such cholesteatoma. A review of the literature and pathogenesis of congenital cholesteatoma is discussed.

[Primary sclerosing cholangitis and autoimmune cochlear deafness: a new syndrome?]. / Cholangite sclérosante primitive et surdité endocochléaire auto-immune: nouveau syndrome?

Association of autoimmune cochlear hearing loss with primary sclerosing cholangitis is reported in two patients. Endocochlear sensorineural hearing loss was associated with the presence of anti-cochlear antibodies in the serum directed against the walls of vessels in the stria vascularis. The hearing loss appeared at the same time or shortly after the diagnosis of cholangitis. This association, which has never been described, may reinforce the theory of the role of immunologic factors in the pathogenesis of primary sclerosing cholangitis, possibly linked to or initiated by vasculitis.

[Neuroendocrine giant-cell epithelioma. Description of a clinical case and review of the literature]. / Les épithéliomas neuroendocrines à grandes cellules. Description d'un cas clinique et revue de la littérature.

Neuroendocrine tumors are rare neoplasms of the larynx and hypopharynx. This tumors are divided in paragangliomas (usually benign, although malignant case have been reported), large cell neuroendocrine carcinoma, described in this case as a primary pharyngo-laryngeal locate, and small cell neuroendocrine carcinoma (characterized by early and diffuse metastatic disease, and best treated by radiotherapy and chemotherapy). Through the international literature, the authors reviewed the characteristics of the large cell neuroendocrine tumors and their management.

[Tumors of the parotid area. Apropos of 203 surgical explorations]. / Les tumeurs de la région parotidienne. A propos de 203 explorations chirurgicales.

The authors present their clinical, radiological and histological conclusions, according to a retrospective personal study about 203 chirurgical explorations from the parotid gland. The pleomorphic adenoma and the cystadenoma are presented more precisely and basically their chirurgical indications; the other histological types met are only presented through several tables.

[Extensive cervical hematoma complicating multinodular goiter. Apropos of a case]. / Hématome cervical extensif compliquant un goitre multinodulaire. A propos d'une observation.

The massive hemorrhagic accidents of multinodular goiter are very rare, implicating the vital prognosis through an airway obstruction by tracheal compression. To illustrate this situation, the authors present an original case with a large cervico-thoracic hematoma without any respiratory's difficulties. The serious evolutive potential of that situation in spite the unworrying aspect of the patient, bring them to operate in delayed emergency.

[Pharyngeal obstruction and the functional adaptation of the natural posture of the head and the hyoid bone in sleep apnea syndrome]. / Obstruction pharyngienne et adaptation fonctionnelle de la posture naturelle de la tête et de l'os hyoïde dans le syndrome d'apnées du sommeil.

Variations in natural head posture (NHP) and hyoid bone (HB) positioning impart changes in the size and shape of the pharyngeal airways. In SAS, which was shown to be correlated with detrimental craniofacial anatomical conditions, control of pharyngeal permeability is lost during sleep. The aim of this study was determine if functional adaptation of NHP and HB position to these detrimental conditions could be observed, using Bonferonni probabilities, in a cephalometric comparison of 38 SAS adults in the wakeful state and a control group of 38 healthy adults. Since HB relationships with craniofacial anatomical structures vary with the positioning of the head, the cephalograms were taken according to the preliminarily tested NHP, thus making the method reproducible. In SAS craniovertical angulation was unchanged, but the head was maintained in a forward position (increased cervico-vertical angulation, P < 0.001). Maintenance of an acceptable pharyngeal permeability was associated with a more distant positioning of HB from the cervical column (P < 0.01) and from craniofacial references (P < 0.001). In spite of these facts lower pharynx opening was still reduced (P < 0.05). Soft palate and facial divergence were expectedly increased in the apneic group. All the individuals but one control could be correctly reclassified with the help of soft palate length, facial divergence, and two HB related variables. Prevention of pharyngeal collapsibility in SAS seems to be commonly associated with functional adaptation of NHP and HP position. The precise control mechanisms of this adaptation remains to be elucidated. Skeletal predispositions to SAS do probably develop already during infancy.

[Rhabdomyosarcoma of the nasopharynx occurring with immunosuppressive treatment with cyclosporin A. Apropos of a case]. / Rhabdomyosarcome du cavum apparu sous traitement immunosuppresseur à la ciclosporine A. A propos d'un cas.

The authors report the case of a 15 year old adolescent who presents a rhabdomyosarcoma of the rhinopharynx. This young patient underwent 23 months before a kidney transplantation and was since under immunosuppressing treatment including corticoids, azathioprine and cyclosporin A. The characteristics of this tumor make it probably induced by the therapeutic based on cyclosporin.

[External injuries of the larynx. Our experience apropos of 55 cases]. / Les traumatismes externes du larynx. Notre expérience à propos de 55 cas.

Reporting 55 cases of laryngeal trauma, the authors detail the etiologies and the lesions observed and expose their trauma management. Endoscopic results are basic in the evaluation of the gravity of the trauma. Radiological investigations, especially C.T. scan, take the second place. The use of endolaryngeal stent in the surgical treatment is as limited as possible. A precise lesional staging and a great rigour in the operative management can only guarantee the recovery of normal vocal and respiratory functions.

[ORL metastases of Grawitz's tumors]. / Métastases ORL des tumeurs de Grawitz.

Renal cell carcinoma (Grawitz's tumor), may metastasize to the head and neck region at different stages of its evolution. The authors present four cases illustrating the difficulties of the preoperative and histopathological diagnosis. The data on otolaryngological localisations are reviewed.

Cephalometric evaluation of pharyngeal obstructive factors in patients with sleep apneas syndrome.

To determine accurately the morphological characteristics specific to patients with sleep apneas syndrome (SAS), a group of 43 adult males with SAS was compared in a cephalometric evaluation with a homologous control group. In SAS patients, the soft palate was elongated; the sagittal dimensions of upper face and anterior cranial base were reduced and correlated with reduced bony pharynx opening; and the increased lower face height was associated with a retruded position of the chin and tongue, thus contributing to lower pharynx crowding. With the four variables entering the discriminant function analysis, 93 percent of the whole population was correctly classified. If anatomical rehabilitation of the pharynx is to be envisaged, the leading factors to consider should be: soft palate length, maxillary position, chin and tongue position, in that order.

Craniofacial characteristics in patients with obstructive sleep apneas syndrome.

Obstructive sleep apneas syndrome (OSAS) has been associated with a clinical reduction of the pharyngeal spaces. To define whether predisposing skeletal craniofacial conditions exist in OSAS patients, 32 OSAS adult patients were compared in a cephalometric investigation with a control sample of 40 adults with ideal dentofacial traits. A t-test assessed the statistical significance of the differences in the two groups; correlation matrix tabulation and discriminant function analysis helped in the identification of the influence of different variables in segregation of the two populations. The following observations were made: There were no differences in maxillary or mandibular prognathism between the two groups. The sagittal dimension of the cranial base was significantly reduced in the OSAS sample, as was the bony pharyngeal opening and maxillary length. This posterior facial compression was associated with increased lower face height (p less than 0.01 in all cases). There were significant correlations in both groups between cranial base length or angulation and pharyngeal opening (p less than 0.01). Eighty percent of the population was correctly sorted out using the discriminant function analysis, with only eight controls and five OSAS patients misclassified. However, this analysis suggested that factors other than the cephalometric may be involved in OSAS.

Flow-volume curve abnormalities and obstructive sleep apnea syndrome.

Recent reports have suggested that flow volume curve abnormalities may be of interest in the diagnosis of obstructive sleep apnea syndromes by showing either extrathoracic airway obstruction (ratio of expiratory flow to inspiratory flow at 50 percent of forced vital capacity [FEF50/FIF50] exceeding 1) or upper airway fluttering (indicated by a sawtooth aspect on the mid-half of the inspiratory part of the curve) or both. In our study, 57 patients referred for a suspected sleep apnea syndrome (SAS) underwent conventional spirometry, assessment of flow-volume curves, ENT examination, and polysomnography. Thirty patients had an obstructive SAS, four patients a central SAS, and 23 patients no SAS. Signs of upper airway fluttering (the sawtooth sign) were present in 61 percent of the patients with obstructive SAS and in 46 percent of the patients without obstructive SAS (central SAS or no SAS). Signs of extrathoracic upper airway obstruction (FEF50/FIF50 greater than 1) were present in 67 percent of the patients with obstructive SAS and in 71 percent of the patients without obstructive SAS. These results suggest that upper airway abnormalities, as reflected by abnormal flow volume curves, are not always associated with obstructive SAS; they favor the hypothesis of a central component in the mechanism of upper airway occlusion during sleep.

[Alveolar hypoventilation during sleep in pharyngeal obstruction caused by lymphoid hypertrophy in children]. / Hypoventilation alvéolaire du sommeil au cours de l'obstruction pharyngée par hypertrophie lymphoïde chez l'enfant.

Twenty-four children suspected of having apnea induced by lymphoid pharyngeal obstruction were studied by nocturnal polygraphy. The data recorded were: instantaneous cardiac frequency, thoracic movements, naso-oral flux, transcutaneous PO2 and PCO2. Episodes of hypoxemia and of hypercapnia related to obstructive apneas were found in 19 children; the mean of the lowest values of PtcO2 during sleep was 58.4 mmHg versus 85 mmHg during wakefulness. The mean od the highest values of PtcCO2 was 50 mmHg during sleep versus 40 mmHg during wakefulness. Six children presented with marked hypoxemia (PtcO2 less than or equal to 50 mmHg). Transcutaneous blood gas monitoring is indicated in all children presenting with sleep disorders due to pharyngeal obstruction. The finding of a marked hypoxemia should suggest removal of the obstacle concerned.