Tailoring of magnetism & electron transport of manganate thin films by controlling the Mn-O-Mn bond angles via strain engineering.

Strain engineering beyond substrate limitation of colossal magnetoresistant thin (La0.6Pr0.4)0.7Ca0.3MnO3 (LPCMO) films on LaAlO3-buffered SrTiO3 (LAO/STO) substrates has been demonstrated using metalorganic aerosol deposition technique. By growing partially relaxed 7-27 nm thick heteroepitaxial LAO buffer layers on STO a perfect lattice matching to the LPCMO has been achieved. As a result, strain-free heteroepitaxial 10-20 nm thick LPCMO/LAO/STO films with bulk-like ferromagnetic metallic ground state were obtained. Without buffer the coherently strained thin LPCMO/STO and LPCMO/LAO films were insulating and weakly magnetic. The reason for the optimized magnetotransport in strain-free LPCMO films was found to be a large octahedral Mn-O-Mn bond angle φOOR ~ 166-168° as compared to the significantly smaller one of φOOR ~ 152-156° determined for the tensile (LPCMO/STO) and compressively (LPCMO/LAO) strained films.

Reconstruction of Angstrom resolution exit-waves by the application of drift-corrected phase-shifting off-axis electron holography.

Phase-shifting electron holography is an excellent method to reveal electron wave phase information with very high phase sensitivity over a large range of spatial frequencies. It circumvents the limiting trade-off between fringe spacing and visibility of standard off-axis holography. Previous implementations have been limited by the independent drift of biprism and sample. We demonstrate here an advanced drift correction scheme for the hologram series that exploits the presence of an interface of the TEM specimen to the vacuum area in the hologram. It allows to obtain reliable phase information up to 2π/452 at the 1 Å information limit of the Titan 80-300 kV environmental transmission electron microscope used, by applying a moderate voltage of 250 V to a single biprism for a fringe spacing of 1 Å. The obtained phase and amplitude information is validated at a thin Pt sample by use of multislice image simulation with the frozen lattice approximation and shows excellent agreement. The presented method is applicable in any TEM equipped with at least one electron biprism and thus enables achieving high resolution off-axis holography in various instruments including those for in-situ applications. A software implementation for the acquisition, calibration and reconstruction is provided.

Langmuir analysis of electron beam induced plasma in environmental TEM.

The characterisation of the gas state under electron impact is of high importance for the understanding of materials in-situ environmental transmission electron microscopy (ETEM) experiments. We report on the formation of a dilute plasma state of Ar and He based on the development of a Langmuir probe as a plasma diagnostic tool for the differentially pumped volume at the TEM sample position in the octagon. In order to keep stray magnetic field influences of the objective lens small, and thus the results readily interpretable within existing theory, the experiments are performed in Lorentz mode. The applicability of Langmuir type analysis for the identification of plasma parameters, such as ion density, plasma temperature, sheath extension and electron energy distribution is examined. The systematic study as a function of gas pressure and beam current reveals cold plasma characteristics with electron temperatures of around 0.4 eV and ion and electron densities that are orders of magnitude below the expected values from ionisation cross sections. The loss of charged particles appears to be due to surface collisions at the electrically conducting pole piece surfaces as well as at the conductive parts of the TEM holder.

Nanometer-resolved quantification of mechanical response in nanoparticle-based composites.

Nanocomposites constitute an upcoming class of materials that has enormous potential within a broad range of areas, particularly with regard to mechanical applications. However, the tuning of material properties requires a full understanding of the mechanical response of the nanocomposite across all length scales. While characterization from the micro to macroscale is well established at this point, quantification of mechanical behavior at the nanoscale is still an unresolved challenge. With this background, the current work demonstrates the capabilities of quantitative contact resonance atomic force microscopy (CR-AFM) to localize and reliably characterize Ni nanoparticles that are embedded below the surface of thermally oxidized silicon thin films. Correlating these results with numerical simulations as well as high-resolution transmission electron microscopy measurements provides a comprehensive understanding of the subtle interplay between the structure and nanomechanical response of the composite.

An analysis of patient grievances in a dental school clinical environment.

Patient satisfaction is an integral part of assessing the quality of oral health care. As dental care becomes more impersonal, competitive, and expensive, the potential for patient complaints is on the rise. Dental school clinics may be more vulnerable to patient grievances due to inexperienced student providers, less efficient delivery of care, challenges related to continuity of care, and the complexity of adhering to institutional policies. Effective management of patient complaints can assist both individuals and institutions toward providing the highest quality of care achievable in the demanding dental education environment. Despite the obvious benefit, there is a dearth of recent studies that analyzed complaints in either the private practice setting or dental school clinics. The purpose of this study was to categorize and analyze the complaints received from patients seeking treatment at a large dental school clinic from 2005 to 2008. It was found that the combined complaints for all four years in descending order were regarding appointment, communication, money, quality, and other. No statistically significant association was found between the type of complaint and time of year. Most importantly, it was found that the system for recording complaints needed to be standardized in order to improve the quality of patient care. The findings from this study will not only facilitate adjustment of the school's current curricula and policies, but could also guide other institutions and private dental practitioners toward better patient care.

Ericksonian hypnosis in tinnitus therapy: effects of a 28-day inpatient multimodal treatment concept measured by Tinnitus-Questionnaire and Health Survey SF-36.

For the first time, the therapeutic effects on subacute and chronic tinnitus of an inpatient multimodal treatment concept based on principles of Ericksonian hypnosis (EH) were examined by standardized criteria of the Tinnitus Questionnaire (TQ) and Health Survey (SF-36) within a controlled prospective, longitudinal study. A total of 393 patients were treated within an inpatient closed-group 28-day-setting based on a resource-oriented, hypnotherapeutic concept. The severity of tinnitus was assessed by TQ at times of admission, discharge and also at a 6- and 12-month follow-up. Health-related quality of life was evaluated before and after therapy using the SF-36. After therapy, a decrease in TQ score was seen in 90.5% of the patients with subacute tinnitus and in 88,3% of those with chronic tinnitus. Assessment of the TQ score at the end of therapy revealed highly significant improvements of 15.9/14.1 points in mean. Effect sizes in the treatment groups (0.94/0.80) were superior to those in the waiting-list controls (0.14/0.23). The TQ score remained stable in the follow-up controls. Significant improvement in health-related quality of life has been observed within the treatment groups depending on initial level of tinnitus serverity I-IV according to TQ. Using a multimodal treatment concept with emphasis on resource-activating approaches of EH the annoyance of tinnitus can be significantly reduced while health-related quality of life is enhanced within a comparatively short treatment period of 28 days.

Lymph node staging in extracranial head and neck cancer with FDG PET--appropriate uptake period and size-dependence of the results.

AIM: Identification of a rationale for the appropriate uptake period for static clinical extracranial head and neck PET imaging and evaluation of the diagnostic accuracy of such an optimized FDG PET approach for lymph node staging in the head and neck region. METHODS: In a subset of 5 patients, kinetic tumour studies were performed in order to identify the cellular activity plateau phase of FDG accumulation for head and neck cancer. Seventy-eight consecutive patients (11 women, 67 men; mean age +/- SD: 55 +/- 11 years; range, 36-78 years), presenting with histologically proven squamous cell carcinoma and sonographically detected lymph nodes in 86 neck sides, underwent clinically indicated FDG PET imaging. PET results were compared to those derived from histological examinations and follow-up imaging results after 6 months in order to calculate sensitivity and specificity for lymph node staging. RESULTS: FDG kinetics in head and neck cancer indicate that the cellular activity plateau of FDG accumulation is reached after an uptake period of 90 min. Using this protocol metastatic involvement of neck sides with lymph nodes less than 1 cm in diameter was correctly identified with a sensitivity of 71.4% and a specificity of 92.3%. Sensitivity increased with the lymph node diameter (1.1-1.5 cm 83.3%, 1.6-2.0 cm 100%, > 2 cm 88.9%). CONCLUSION: The appropriate uptake period for static clinical extracranial head and neck PET imaging that allows measurements in the activity plateau phase is about 90 min. FDG PET may add some significant information regarding metastatic spread into regional lymph nodes.

Homozygosity mapping of a gene locus for primary ciliary dyskinesia on chromosome 5p and identification of the heavy dynein chain DNAH5 as a candidate gene.

Reduced mucociliary clearance in primary ciliary dyskinesia (PCD) causes recurrent infections of the upper and lower respiratory tract. The disease is usually inherited as an autosomal recessive trait. To identify a gene locus for PCD, we studied a large consanguineous family of Arabic origin. Direct examination of the respiratory cilia revealed ciliary akinesia. Electron microscopic examination of cilia showed absence of the outer dynein arms. Two of four affected individuals exhibited a situs inversus, typical for Kartagener syndrome, due to randomization of the left/right body axis. A total genome scan with 340 highly polymorphic microsatellites was performed. We localized a new gene locus for PCD to a region of homozygosity by descent on chromosome 5p15-p14 with a parametric multipoint logarithm of odds ratio (LOD) score of Zmax = 3.51 flanked by markers D5S2095 and D5S502 within an interval of 20 centimorgans sex-averaged genetic distance. Applying a polymerase chain reaction-based approach, we identified a 1.5-kb partial complementary DNA of DNAH5 encoding a Chlamydomonas-related axonemal heavy dynein chain within the critical disease interval of this new PCD locus. On the basis of the Chlamydomonas model for PCD, this gene represents an excellent candidate for PCD.

Focal dermal hypoplasia (Goltz-Gorlin syndrome) associated with obstructive papillomatosis of the larynx and hypopharynx.

A 14-year-old girl with focal dermal hypoplasia (Goltz-Gorlin-syndrome) presented with dysphagia, hoarseness, inspiratory stridor, intermittent dry cough and a 10% weight loss. Endoscopy showed that these symptoms were caused by papillomatosis of the hypopharynx and the larynx. The papillomatous masses were resected subtotally by endoscopic laser treatment. Residual papillomas were left in the subglottic space but tracheotomy could be avoided. Complete clinical recovery with adequate weight gain as well as, resolution of dyspnoe and dysphagia resulted after the intervention. Histological examination did not show morphological signs of human papilloma virus as an etiological agent.

[The myocutaneous sternocleidomastoid flap for reconstruction of the mouth cavity and pharynx]. / Der myokutane Sternocleidomastoideus-Lappen zur Rekonstruktion in Mundhöhle und Pharynx.

BACKGROUND: Among the myocutaneous island flaps applied for reconstruction of large soft-tissue defects after ablative surgery for malignomas, the pectoralis major flap is the one most frequently used. In comparison, the sternocleidomastoid myocutaneous island flap is not as popular. METHODS: We report on our experiences with the superiorly based sternocleidomastoid myocutaneous (SCM) island flap (cutaneous island of 6-8 cm in diameter) in seven consecutive cases after resection of malignomas of the oral cavity and the pharynx. The vascularization from the occipital artery is additionally supplied by preserving the platysma during preparation of the SCM flap. RESULTS: Only one total cutaneous necrosis was observed in a patient who had received prior radiation. In the other 6 cases no major complications (necrosis or fistula) occurred. CONCLUSION: When the preservation of the sternocleidoid muscle does not compromise oncologic principles as in cases with limited lymphe node involvement (N0-N1), the SCM flap appears to be a useful and simple technique, particularly in female patients compared with the pectoralis major flap, in addition to others.

MRI of active otosclerosis.

Our aim was to determine whether MRI reliably shows pathology in patients with active otosclerosis (otospongiosis). We studied five patients with clinical and audiometric signs of this disorder and positive findings on high-resolution CT and tympanocochlear scintigraphy. Contrast enhancement of otospongiotic lesions was found in all affected ears, and could be topographically related to demineralised otospongiotic foci on CT. In lesions in the lateral wall of the labyrinth MRI sometimes showed the pathology better than CT, where partial-volume effects could be troublesome.

Middle ear pressure and dysfunction of the labyrinth: is there a relationship?

Relationships between middle ear pressure and non-infection-related cochleovestibular dysfunction have been suggested by several authors. According to some data, vertiginous attacks can be prevented by the insertion of a ventilation tube in patients suffering from Meniere's syndrome. The aim of our study was to investigate if the incidence of eustachian tube malfunction and pathologic middle ear pressure is frequent, and if routine implantation of ventilation tubes is reasonable in ears with dysfunctions of the labyrinth, including clinical Meniere's syndrome. So, we determined in our pressure chamber all active and passive parameters of eustachian tube function in 40 patients suffering from Meniere's syndrome, sudden sensory hearing impairment (SSHI), or vestibular neuronitis. Our results disclosed no nonrandom incidence of impaired tubal function among our patients compared to healthy control subjects. Pressure equalization was sufficient in most patients suffering from clinical Meniere's syndrome, and only one patient with vestibular neuronitis presented with a patulous tube. Our results show that impairment of vestibular or cochlear function is not regularly accompanied by eustachian tube dysfunction. Furthermore, no patient reported symptoms while pressure variation was performed. We conclude that variation of middle ear pressure does not usually play a role in the genesis of Meniere's syndrome, vestibular neuronitis, or SSHI. Thus, from our data, we cannot recommend routine implantation of tympanic ventilation tubes in patients suffering from Meniere's syndrome, vestibular neuronitis, or sudden hearing loss.

Living epithelial-mesenchymal compounds formed in vitro suitable for autografting.

Three different, human epithelial-mesenchymal compounds (EMC) were generated in vitro for prospective grafting in epithelial defects. All compounds consisted of a fibroblast-populated collagen lattice as a mesenchymal component seeded with different types of cultured epithelial cells isolated from biopsies of healthy skin, oral mucosa and respiratory mucosa. Maturation of the epithelial cells was enabled by the presence of a high calcium concentration (1.8 mM) when cultures were lifted to the air-liquid interface. Light and electron microscopy revealed moderate differentiation of the multilayered epithelium in all compounds as well as basement membrane development at the epithelial-mesenchymal junction after 2-3 weeks. A coherent, tissue-like consistency of the collagen lattice and the presence of a basement membrane preventing detachment of the epithelium permitted easy handling and even loose suturing of the compounds produced.

Experimental topographic study of high-resolution tympanocochlear scintigraphy using the human temporal bone model.

To determine the diagnostic value of tympanocochlear scintigraphy (TCS), which is still used for the visualization of alterations of labyrinthine bone metabolism due to active otosclerosis, resolution and detection limits were examined in a normal human temporal bone model. After incubation in technetium-99m-labeled diphosphonate solution, scintigraphic imaging showed the zygomatic process and the clivus as landmarks for fine structures of the petrous bone. For further differentiation, labyrinthine fine structures were marked with radioactive tracers of 0.5-1 mm2 each. High-resolution scintigraphic imaging gave two-point discrimination for structures as small as 2.5 mm apart. Localization of the activity patterns was improved by correlating imaging with X-ray photographs or by superimposition with masks of the prepared temporal bones drawn from the X-rays. The correlation of scintigraphic findings with X-ray photographs was found to provide a powerful method for improving the accuracy of localizing temporal bone metabolic changes as it is applicable clinically for studying the occurrence of small active otosclerotic foci.

Localization of active otosclerotic foci by tympano-cochlear scintigraphy (TCS) using correlative imaging.

High-resolution, tympano-cochlear scintigraphy (TCS) is a useful tool for visualizing changes in labyrinthine bone metabolism in active otosclerosis in vivo. But until now, the activity patterns have mostly been rather imprecisely ascribed to the labyrinthine structures; more exactly by means of high-resolution CT (HR-CT). Experimental studies on TCS using a human temporal bone model revealed that correlative imaging of X-ray photographs and the scintigrams or superimposition with masks of the temporal bone drawn from the X-rays can facilitate the localization of small foci of about 0.5-1 mm. Clinical applications of the visualization technique, combining functional with structural images, confirmed the benefit of this method, improving the accuracy in detection and localization of focal activity enrichment of the petrous bone in cases of active otosclerosis by means of TCS.

[Changes in the auditory threshold for air and bone conduction in relation to middle ear pressure in probands with normal hearing]. / Veränderung der Hörschwellen für Luft- und Knochenleitung in Abhängigkeit vom Mittelohrdruck bei Normalhörenden.

Under pressure in the tympanic cavity causes increased impedance of the middle ear. Gellé was the first to describe increased bone conduction levels following alteration of ear canal pressure in healthy ears. Up to now, no investigation which quantitatively describes the elevation of the hearing threshold induced by various levels of under pressure in the middle ear has been published. In a pressure chamber, we induced relative under pressure in the middle ears of 15 adults with normal hearing. We measured hearing thresholds and calculated medium values at four separate levels of under pressure. At an under pressure of 3.3 kPa, air conduction was reduced by a few dB at 500 and 1000 Hz. Alterations of bone conduction were first seen at 6.6 kPa accompanied by increased deterioration of air conduction. Both effects became more obvious at 10 kPa; and at a maximum under pressure of 13.3 kPa, a deterioration of air conduction by more than 25 dB was seen at 250, 500, and 1000 Hz. Bone conduction deteriorated by more than 10 dB at 500 and 1000 Hz. There was no uniformity in the development of bone conduction threshold in the condition of under pressure: Several ears expressed only slight changes, but in some ears we saw an increase of bone conduction at the same rate as air conduction. Minor alterations were observed in frequencies above 1000 Hz. These results may be only partially explained by middle ear effects like the reduction of the ostio-tympanic component of bone conduction caused by increased stiffness of the ossicles. We believe that disturbances of inner ear mechanics play a role in the deterioration of bone conduction levels, too.(ABSTRACT TRUNCATED AT 250 WORDS)

Tracheal stenting for malignant tracheoesophageal fistula.

Palliative intubation of the esophagus for a malignant tracheoesophageal fistula is often complicated by difficulty in obtaining a tight seal. We have overcome the problem in three instances by placing a bifurcated, foam-cuffed stent in the trachea.

Detection of cochlear dysfunction by the measurement of transiently evoked otoacoustic emissions in guinea pigs with autoimmune-induced labyrinthitis.

For the evaluation of functional inner ear lesions caused by an autoimmune-induced labyrinthitis, transiently evoked otoacoustic emissions (TEOAEs) were detected in guinea pigs before and after transfer of sensitized lymphocytes from animals suffering from a labyrinthitis induced by the foreign protein keyhole limpet hemocyanin (KLH). Initially TEOAEs were detectable from 47 of 62 ears (76%) in healthy guinea pigs. These animals then were used as recipients for sensitized lymphocytes from donors exclusively. Three months after cell transfer the incidence of TEOAEs was reduced to 48% in animals receiving lymphocytes from donors sensitized with KLH intradermally and intracochlearly. In recipients of lymphocytes from donors sensitized only intradermally and in untreated animals no significant alteration of the TEOAE incidence was found. These findings showed strong correlation with those from scanning electron microscopy of the organ of Corti, indicating that the measurement of TEOAE is a useful, time-saving tool for the detection of cochlear dysfunction caused by sensitized lymphocytes in experimental animal. The present findings also show that the migration of sensitized lymphocytes actually leads to functional lesions in the cochlea.

Osteogenesis imperfecta: clinical symptoms and update findings in computed tomography and tympano-cochlear scintigraphy.

Osteogenesis imperfecta (OI) is an autosomal-dominantly inherited connective tissue disorder characterized by abnormal bone fragility combined with blue sclerae. The association of OI with hearing impairment is commonly known as Van der Hoeve-de Kleyn syndrome. Besides typical symptoms we here report on findings by high resolution CT and by high resolving scintigraphy of the labyrinthine capsule in 3 families (9 patients) with OI, which resemble those in otosclerosis (OS): In 4 of 6 cases with OI and mixed hearing loss, severely decreased peri-cochlear bone density was established by CT. In these cases, increased bone metabolism could be revealed by high resolving tympano-cochlear scintigraphy (TCS) in the cochlear region. In 2 patients with mixed hearing loss and 3 cases without hearing impairment or with slight conductive hearing loss, bone alteration was not detectable by CT and TCS. These results raise the question whether OI and OS lead to similar labyrinthine bone alterations, based on different aetiologies or whether these diseases may co-exist, OS being part of OI.