bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of topical anesthesia on acoustic characteristics of voice during laryngeal telescopic examination
Authors: Yang Cheng‐Chien , Chen Sheng Hwa
Published: January 2005

OBJECTIVE

The purposes of this study are to investigate the impact of topical anesthetic alone and with concurrent laryngeal telescopic examination on acoustic characteristics of vocal fold function. Comparison with phonation in controlled conditions may imply diagnostic information from the examination.

STUDY DESIGN

Thirty males evaluated as having a normal voice were included in the study. The subjects were asked to phonate sustained /i/ with a naturally comfortable pitch and loudness in three consecutive experimental sequences as “control condition,” “anesthetic condition,” and “telescopic condition.” Acoustic analysis of fundamental frequency, jitter, shimmer, and harmonic to noise ratio in the three different conditions were executed.

RESULTS

The mean and standard deviation of Fo in control condition, anesthetic condition, and telescopic condition were 130.1 ± 18.5 Hz, 125.7 ± 19.7 Hz, and 173.2 ± 35.1 Hz, respectively. The telescopic condition showed more negative change than that in control condition and anesthetic condition in other parameters. There was a significant difference (P < 0.001) between control condition and telescopic condition in all four parameters.

CONCLUSIONS

This study showed that anesthesia has little effect on voice performance for subjects with a normal voice. On the other hand, the acoustic characteristics changed significantly during telescopic performance. When doing interpretation of acoustic data, the abnormality of the acoustic characteristics might be the result of the procedures and not reflect vocal pathology. Laryngeal variations due to manipulation of telescope should be ruled out.
Intracranial complications of otitis media: 15 years of experience in 33 patients
Authors: Penido Norma De Oliveira , Borin Andrei , Iha Luiz C.N. , Suguri Vinicius M. , Onishi Ektor , Fukuda Yotaka , Cruz Oswaldo Laércio M.
Published: January 2005

OBJECTIVES

Complications in the central nervous system (CNS) from acute otitis media (AOM) and chronic otitis media (COM) are becoming fewer, although they still represent a challenge for early recognition, adequate treatment, and satisfactory results. This retrospective study analyzed clinical data and therapeutic options in 33 patients with intracranial involvement resulting from otitis media. Important clinical features of intracranial complications and the sequence of the most efficient therapeutic maneuvers are discussed.

METHODS

Charts of six patients with AOM and 27 patients with COM associated with CNS complications were analyzed for clinical presentation, imaging, and therapeutic approach.

RESULTS

Ages ranged from 6 months to 79 years, with no gender predilection. Persistent fever, headache, and purulent otorrhea were the main symptoms. Proteus mirabilis, Enterococcus, and Pseudomonas aeruginosa were the most common microorganisms in COM, and Pneumococus and Haemophilus were the most common microorganisms in AOM. Nineteen patients (58%) presented with more than 1 CNS complication, resulting in a total of 56 complications, including 26 cases of otogenic brain abscess, 21 cases of meningitis, 5 cases of lateral sinus thromboses, two cases of subdural empyemas, 1 case of epidural empyema, and 1 case of meningocele. Surgical interventions included craniotomy and drainage of the abscess (n = 17), open mastoidectomy with abscess drained through the mastoid (n = 10), open mastoidectomy alone (n = 8), and closed mastoidectomy (n = 2). Twelve patients who underwent craniotomy had subsequent mastoidectomy for recurrent abscess. At the 6‐month, 66% of patients presented without sequelae, 24% presented with sequelae, and 9% died.

CONCLUSION

Early identification and prompt clinical and surgical intervention with mandatory drainage of the middle ear (primary disease), was essential for better outcome.
Survival outcomes for second primary head and neck cancer: A matched analysis
Authors: Bhattacharyya Neil , Nayak Vijay K.
Published: January 2005

OBJECTIVE

Determine whether survival for second primary head and neck cancer is truly poorer than survival for first primaries.

METHODS

From the Surveillance, Epidemiology and End Results database, 2 cohorts were constructed. One cohort consisted of patients with exactly 1 head and neck primary malignancy; the second cohort consisted of patients with exactly 2 head and neck primaries, restricted to second primaries of the tongue, tonsil, glottic larynx, and hypopharynx with squamous cell carcinoma (SCCA) histology. Demographic and extent of disease data were extracted. For each primary site, matched Kaplan‐Meier survival analysis was conducted comparing overall survival between the two cohorts matching for primary site, year of diagnosis, age, gender, and cancer stage.

RESULTS

A total of 242 cases of second head neck primary were successfully matched to patients with single primary disease. Among 96 patients with oral tongue SCCA, mean (median) survival was 40.1 (28) months after the second primary diagnosis versus 52.2 (32) months for matched single primary patients (P = 0.552, log‐rank test). Among 45 tonsillar carcinomas, mean survival was 42.8 (30) versus 90.9 (NA) months for the second primary and single primary cohorts, respectively (P = 0.028). Among 52 matched glottic carcinomas, mean survival was 46.4 (27) versus 103.5 (120) months for the 2 cohorts, respectively (P < 0.001). Among 49 hypopharyngeal carcinomas, mean survival was 35.6 (19) versus 53.9 (21) months, respectively (P = 0.373).

CONCLUSIONS

Survivals for second primary head and neck malignancies may be poorer than survivals for comparable first primaries, but in this analysis we did not find this difference to be statistically significant for all subsites. Second primary survival will vary from site to site. EBM rating: B‐3.
Inhibition of growth and telomerase activity by novel cationic ceramide analogs with high solubility in human head and neck squamous cell carcinoma cells
Authors: Rossi Michael J. , Sundararaj Kamala , Koybasi Serap , Phillips Monique S. , Szulc Zdzislaw M. , Bielawska Alicja , Day Terry A. , Obeid Lina M. , Hannun Yusuf A. , Ogretmen Besim
Published: January 2005

OBJECTIVES

Head and neck squamous cell carcinoma (HNSCC) is notoriously resistant to chemotherapy. The sphingolipid ceramide and its analogs have been demonstrated to exert antitumor activity in many cell types; however, the effectiveness of these analogs has been limited by potency and solubility. This study focuses on the effects of novel highly soluble cationic pyridinium‐ceramides, alone and in combination with various chemotherapeutic agents, on cell survival, telomerase activity, and cell cycle arrest in HNSCC cell lines in vitro.

METHODS

The concentration of pyridinium‐ceramides and chemotherapeutic agents that inhibited cell growth by 50% (IC50) was determined by MTT cell survival assays. The cell cycle profiles were determined by flow cytometry. Telomerase activity was determined by telomerase repeat amplification protocol (TRAP) assay.

RESULTS

Treatment of the human UM‐SCC‐22A (SCC of the hypopharynx) cells, as well as various other HNSCC cell lines, with C6‐Pyr‐Cer resulted in the inhibition of cell survival with an IC50 concentration of approximately 250 to 300 nM at 96 hours, whereas its IC50 was greater than 1000 nM in noncancerous Wi‐38 human lung fibroblasts, and adult human epidermal keratinocytes. Moreover, treatment with C6‐Pyr‐Cer also resulted in cell cycle arrest in G0/G1, which correlated with a significant inhibition of telomerase activity in UM‐SCC‐22A cells. Additional results demonstrated that the combination of C6‐Pyr‐Cer with gemcitabine (GMZ) or doxorubicin (DOX), which have the lowest IC50 concentrations among various chemotherapeutic drugs in these cells, enhances the effects of these drugs in the inhibition of telomerase and cell growth.

CONCLUSIONS

These data suggest that the novel C6‐Pyr‐Cer with high solubility and bioavailability may lead to the development of new therapeutic strategies that target telomerase for the treatment of HNSCC.
Oral steroid regimens for idiopathic sudden sensorineural hearing loss
Authors: Slattery William H. , Fisher Laurel M. , Iqbal Zarina , Liu Nancy
Published: January 2005

OBJECTIVE

To determine hearing recovery in patients with idiopathic sudden hearing loss treated with varying amounts of oral steroids.

STUDY DESIGN AND SETTING

A retrospective chart review (n = 75) in a tertiary care clinic examined sudden hearing loss patients treated with 1 60‐mg prednisone taper, 1 course of steroid less than a 60‐mg taper, or any 2 courses of oral steroid.

RESULTS

Overall, 35% of the patients recovered a clinically significant amount of hearing. Recovery was associated with immediate treatment (within 2 weeks from onset), better hearing at the onset of treatment, and treatment with the higher dose of prednisone in patients with just 1 additional symptom (dizziness or tinnitus). Patients tended to continue to experience some recovery in hearing up to 4 months after treatment.

CONCLUSION

Immediate treatment of patients with unilateral idiopathic sudden hearing loss and additional symptoms (dizziness or tinnitus) with a 14‐day course of 60 mg prednisone (with taper) is recommended. EBM rating: B‐3.
Pressed scar tissue for tympanic membrane grafting in revision tympanoplasty
Authors: Chang C. Y. Joseph , Gray Lincoln C.
Published: January 2005

OBJECTIVE

Compare the efficacy of pressed scar tissue grafts to standard fascia and areolar tissue grafts for use in tympanoplasty.

STUDY DESIGN

A retrospective review of a prospective computerized database of tympanoplasty and mastoid surgeries at an academic, tertiary care practice was performed. Search parameters were set to find all patients who underwent tympanoplasty with or without mastoidectomy with use of various grafting materials for repair of tympanic membrane perforation from 1996 to 2002. All ages were included. Patients with cholesteatoma at the time of surgery were excluded. The short‐term graft take rate was evaluated at 30 to 90 days to identify any differences in results using the standard fascia and areolar grafts vs. pressed scar tissue grafts. Other parameters that may have an influence on outcome were analyzed including mastoidectomy, infection, perforation size, perforation location, age of patient, primary vs. revision surgery, number of previous surgeries, postauricular vs. transcanal approaches, and medial vs. lateral grafting techniques. Hearing results were analyzed to see whether the use of scar tissue grafts resulted in equivalent outcomes compared to standard graft materials.

RESULTS

There were no statistically significant differences in short‐term tympanic membrane closure rates in subjects undergoing surgery using standard fascia/areolar tissue grafts and pressed scar tissue grafts. Hearing results were also statistically equivalent regardless of graft material used. The only parameter that was somewhat associated with successful closure of tympanic perforation was use of the postauricular approach compared to the transcanal approach.

CONCLUSIONS

Pressed scar tissue grafts are as efficacious as standard fascia and areolar tissue grafts when used to repair tympanic membrane perforations. Pressed scar tissue graft can be used successfully in cases such as revision tympanoplasty when standard tissue grafts are not available or difficult to obtain. EBM rating: B‐3.
Hearing loss and extent of labyrinthine injury in Pseudomonas otitis media
Authors: Malaty John , Lee James C. , Zhang MEI , Stevens Gary , Antonelli Patrick J.
Published: January 2005

OBJECTIVES

To determine if the severity of hearing loss due to semicircular canal transection (SCT) in Pseudomonas otitis media (POM) is a function of the extent of the labyrinthine injury.

METHODS

POM was induced bilaterally in 45 guinea pigs. After 2 to 4 days, SCT was performed in one 1 on the horizontal canal, the superior canal, or both the horizontal and the superior canals. Auditory‐evoked brainstem responses were measured before and after SCT.

RESULTS

POM was induced bilaterally in all animals. Elevation of click thresholds was found in almost all SCT ears of all 3 groups; however, there were no significant differences between groups. Comparing the SCT ear to the contralateral, control ear, mean hearing losses in the horizontal, superior, and horizontal + superior SCT groups were 23 dB, 27 dB, and 24 dB, respectively.

CONCLUSIONS

Hearing loss does not correlate with extent of labyrinthine injury in POM in the guinea pig. EBM rating: B‐2.
Staged resection of large acoustic neuromas
Authors: Patni Aftab H. , Kartush Jack M.
Published: January 2005

OBJECTIVE

Surgical removal of large (>3 cm) acoustic neuromas is associated with poor long‐term facial nerve function results and higher complication rates. This study analyzes whether long term facial nerve function and the incidence of neurological and vascular complications is improved by resection of large acoustic neuromas in 2 or 3 stages.

PATIENTS AND METHODS

Among 660 patients who underwent surgical resection of acoustic neuromas between 1989 and 2002 by the senior author (J.M.K.), 34 (5%) patients underwent a staged resection of their large‐sized tumors: stage I via a retrosigmoid craniotomy and stage II via a translabyrinthine approach. A retrospective chart review was performed. Tumor size, completeness of tumor removal, tumor recurrence, facial nerve function, and any complications were noted.

RESULTS

The average tumor size was 4.4 cm with a mean postoperative length of follow‐up of 6 years after the last surgery. Thirty‐one patients underwent a 2‐staged resection and 3 patients underwent a 3‐staged resection. After their last surgery, 32 (94%) patients had excellent long‐term facial function grades of House‐Brackmann (H‐B) I, one was H‐B III, and one was H‐B VI. All patients had a total or near‐total (>98%) resection. There were no tumor recurrences on follow‐up MRI scans. From these 71 operations, no patients required reoperation for a CSF leak. There were no deaths, strokes, hydrocephalus, or meningitis.

CONCLUSION

In conjunction with the reported technical refinements, staged resection of large tumors significantly reduces morbidity and improves long‐term facial nerve function. EBM rating: C.
The Balkans: Identities, Wars, Memories
Authors: DASKALOV ROUMEN
Published: January 2005

Neven Andjelić, Bosnia-Herzegovina. The End of a Tragedy (London: Frank Cass, 2003), 228 pp., $34.95 (pb), ISBN 0-7146-8431-7.

Tom Gallagher, The Balkans after the Cold War. From Tyranny to Tragedy (London and New York: Routledge, 2003), 256 pp., $114.95 (hb), ISBN 0-415-27763-9.

John Lampe and Mark Mazower, eds., Ideologies and National Identities. The Case of Twentieth-Century Southeastern Europe (Budapest and New York: Central European University Press, 2004), 309 pp., $23.95 (pb), ISBN 9639241822.

James Pettifer, ed., The New Macedonian Question (Basingstoke and New York: Palgrave and St. Martin's Press, 1999), 311 pp., $24.95 (pb), ISBN 0-333-92066-X.

Michael Parenti, To Kill a Nation. The Attack on Yugoslavia (London and New York: Verso, 2000), 246 pp., $10.00 (pb), ISBN 1-85984-366-2.

Maria Todorova, ed., Balkan Identities: Nation and Memory (London: Hurst & Co., 2004), 374 pp., £17.50 (pb), ISBN 1-850-65715-7.

Emerging from the obscurity of old-fashioned, specialised ‘area studies’, since 1989 the Balkans have attracted much attention from historians. The primary reason for that has been, tragically, the war in Yugoslavia and the emergence of a postwar order. Even the post-communist transitions (in Romania, Bulgaria and Albania) attracted less attention. Nevertheless, the field benefited substantially from the increased interest in the area, and lively debates took place on contested issues, sparked not least by hasty initial schemata (and stigmata) used by outside observers, such as ‘ancient hatreds’ and the like. Parallel to the attention paid to what was going on in Yugoslavia, and perhaps more productively in the long run, was the postmodern, postcolonial approach to Balkan history, inspired by Maria Todorova's Imagining the Balkans, which followed Edward Said's monumental Orientalism and appeared parallel to Larry Wolff's Inventing Eastern Europe. Such refreshing studies of Western representations of the region were later complemented by the internal perspective of how such representations were received, and coped with, in the region. A profusion of ‘cultural studies’ in the broadest sense followed, reflecting both the ongoing reshaping of Balkan identities and outside demand for such studies.
A full‐wave investigation of the use of a “cancellation factor” in gravity wave–OH airglow interaction studies
Authors: Hickey Michael P. , Yu Yonghui
Published: January 2005

Atmospheric gravity waves (GWs) perturb minor species involved in the chemical reactions of airglow emissions in the upper mesosphere and lower thermosphere. In order to determine gravity wave fluxes and the forcing effects of gravity waves on the mean state (which are proportional to the square of the wave amplitude), it is essential that the amplitude of airglow brightness fluctuation be related to the amplitude of major gas density fluctuation in a deterministic way. This has been achieved through detailed modeling combining gravity wave dynamics described using a full‐wave model with the chemistry relevant to the airglow emission of interest. Alternatively, others have employed approximations allowing them to derive analytic expressions relating airglow brightness fluctuations to major gas density fluctuations through a so‐called “cancellation factor” (CF). The effects of these approximations on the derived CF are investigated here using a full‐wave model describing gravity wave propagation in a nonisothermal, windy, and viscous atmosphere. This numerical model combined with the chemical reaction scheme for the OH (8, 3) Meinel airglow emission is used to derive fluctuations in the OH* nightglow from which an equivalent CF is calculated. Comparisons are made between the analytically derived CF's and the numerically derived CF's based on using different approximations in the latter model. Differences exist at most wave periods, but they also depend on the horizontal wavelengths of the gravity waves considered. In addition to these different model comparisons, the sensitivity of the numerically derived CF to specific physical processes is examined exclusively using the full‐wave model. These sensitivity tests show that the effect of eddy diffusion marginally influences the calculated CF's only for the very slowest gravity waves. Accounting for the effects of a nonisothermal mean state has a significant influence on the calculated CF's, and the CF's calculated assuming an isothermal mean state can be as much as a factor of 2 smaller than those calculated assuming a nonisothermal mean state. The effects of background mean winds also influence the derived CF's, which then become dependent on the azimuth of propagation. In this case the calculated CF's can vary by a factor of ∼2 from their windless values for gravity waves of short horizontal wavelength with phase speeds less than 100 m s−1. Finally, reflection from the lower and middle thermosphere in the full‐wave model leads to undulations in the calculated CF's as a function of phase speed for gravity waves with horizontal wavelengths of 100 km and phase speeds greater than about 100 m s−1. These effects that are not reproduced in the analytic model lead to large differences between the CF's calculated with and without winds, but they only occur for fast gravity waves that are not usually observed in the airglow.
A new estimator for directional properties of nearshore waves
Authors: Sheremet A. , Guza R. T. , Herbers T. H. C.
Published: January 2005

The infragravity wave (periods between roughly 20 and 200 s) energy balance in shallow, nearshore waters is believed to be effected by generation by groups of sea and swell, dissipation, shoreline reflection, and refractive trapping. Observations obtained with alongshore oriented arrays of current meters or pressure gauges have been previously used to identify concentrations of energy at the frequency‐alongshore wavenumbers of refractively trapped edge waves, but seaward and shoreward propagating waves were not differentiated. Surfzone dissipation theoretically limits edge wave growth, and a different analysis (using the approximation of shore‐normal propagation) shows that the energy flux of shoreward propagating infragravity waves decreases owing to surfzone dissipation. Here an estimator is developed that yields the alongshore wavenumber‐frequency spectra of seaward and shoreward propagating waves, using the WKB approximation and observations from an alongshore‐oriented array of pressure and velocity sensors. Example spectra, estimated using data from the spatially sparse and relatively short SandyDuck arrays, suggests that strong dissipation of shoreward propagating infragravity waves occurs over a wide range of alongshore wavenumbers, effectively suppressing the excitation of edge wave modes.
Accounting for the effect of transport errors on tracer inversions
Authors: Lin J. C. , Gerbig C.
Published: January 2005

Errors in atmospheric transport of tracers lead to errors in estimates of tracer fluxes based upon concentration observations. Typically, such “inverse” methods either neglect transport errors or only assess their effects roughly. We describe a method to quantitatively account for transport errors by incorporating uncertainties in winds into stochastic motions of air parcels. The magnitude of errors in wind fields, as well as their spatiotemporal covariances, are determined by direct comparison of assimilated winds to radiosonde observations. These statistics of transport errors are propagated through stochastic motions of air parcels in a Lagrangian model (STILT). We illustrate this method by conducting an inverse analysis using simulated CO2 observations over the continent and examine the effect of transport errors on estimates of regional terrestrial carbon fluxes. The inverse analysis demonstrates that transport errors can cause significantly biased estimates. We show that the proposed method properly accounts for these errors.
Observation of the horizontal drift of thin metallic ion layers over Sondrestrom
Authors: Bedey David F. , Watkins Brenton J. , Heinselman Craig J. , Zellmann Richard L. , Jakes Edward M.
Published: January 2005

Previous observations of thin metallic ion layers occurring in the lower E region of the polar cap have suggested that such layers drift horizontally, but this impression had not been confirmed by direct measurement of plasma motion within the layers. In this paper, we describe a technique for finding the drift velocity of a thin ion layer, based upon statistical analysis of data gained from an incoherent‐scatter radar experiment, i.e., line‐of‐sight velocities deduced from Doppler analysis of the power spectra of backscatter from within the layer. We applied this technique to two typical layers observed over Sondrestrom and found that considerable horizontal drift was present in both cases. This finding has significant implications for studies of the formation and subsequent time evolution of thin metallic ion layers. In addition, our statistics‐based algorithm can readily be adapted to radar studies of other geophysical phenomena, e.g., determination of F region electric fields.
Using different hydrological variables to assess the impacts of atmospheric forcing errors on optimization and uncertainty analysis of the CHASM surface model at a cold catchment
Authors: Xia Youlong , Yang Zong‐Liang , Stoffa Paul L. , Sen Mrinal K.
Published: January 2005

Estimation of parameters for land‐surface models, along with their corresponding uncertainties, relies on the input data for the atmospheric forcing variables including atmospheric pressure, temperature, humidity, wind speed, precipitation, and incoming shortwave and longwave radiation. Most studies assume that forcing data are accurate and contain no random or systematic observational errors. In practice, there are indeed systematic errors in precipitation measurements, especially for snowfall, due to wind‐caused undercatch. Incoming shortwave and longwave radiation fluxes are often not directly measured, but estimated from empirical formulations. Uncertainties in these forcing data may substantially affect optimization and uncertainty estimates of land surface models. In this study, we used 18‐year forcing and calibration data as well as information about the uncertainties in the forcing variables at Valdai, Russia, to study the impacts of forcing errors on selection of optimal model parameters and their uncertainty estimates when three different hydrological variables were used for calibration. The results show that forcing errors have few effects on the selection of optimal model parameter sets when monthly evapotranspiration and runoff are calibrated. However, forcing errors do introduce significant effects on the selection of optimal model parameters when daily snow water equivalent is calibrated. Forcing errors also significantly affect uncertainty estimates of the land surface model parameters. In addition, constraints of forcing errors are different when different hydrological variables are calibrated. All three hydrological variables constrain the incoming longwave radiation error well, and the snow water equivalent and runoff constrain winter snowfall errors well. However, all three hydrological variables cannot constrain the incoming solar radiation error well. We highlight in this study that runoff is shown to be a good observable to use for calibration, the reason being that it integrates multiple hydrological processes; and the results support the theory that typical rain/snow gauges have 10–20% undercatch.
Hautschutzseminare zur sekundären Individualprävention bei Beschäftigten in Gesundheitsberufen: erste Ergebnisse nach über 2jähriger Durchführung
Authors: Weisshaar Elke , Radulescu Magdalena , Bock Michael , Albrecht Ursel , Zimmermann Elisabeth , Diepgen Thomas L.
Published: January 2005

Hintergrund: Die Beschäftigten der Gesundheitsberufe haben ein erhöhtes Risiko, eine Berufshautkrankheit zu entwickeln. Seit Januar 2002 werden in der Abteilung Klinische Sozialmedizin, Berufs‐ und Umweltdermatologie des Universitätsklinikums Heidelberg in Zusammenarbeit mit der Berufsgenossenschaft für Gesundheitsdienst und Wohlfahrtspflege (BGW) Seminare zur sekundären Prävention von berufsbedingten Hauterkrankungen bei Angehörigen von Gesundheitsberufen durchgeführt. Zielkriterien sind Veränderungen des individuellen Schutz‐ und Pflegeverhaltens, Empfehlungen bezüglich der weiteren Diagnostik und Therapie, langfristige Besserung und Stabilisierung des Hautzustandes und Vermeidung einer Berufskrankheit nach BK 5101.

Patienten und Methodik: Bei den zweitägigen Seminaren nehmen bis zu 14 Hauterkrankte teil. Darin werden sie über Aufbau und Funktion der Haut sowie notwendige Schutzmaßnahmen informiert. In praktischen Seminarphasen üben die Teilnehmer, Hautschutzmaßnahmen in ihre täglichen Arbeitsläufe zu integrieren. Ferner erfolgt eine ausführliche ärztliche Anamnese und Untersuchung. Diese ermöglicht dem Arzt, ein auf die individuellen Bedürfnisse angepasstes Hautschutz‐ und Hautpflegeprogramm auszuarbeiten und den Teilnehmern, alle anfallenden Fragen zu stellen.

Ergebnisse: Von bisher 355 Teilnehmern (Stand: Mai 2004) waren 87,3 % Frauen mit dem durchschnittlichen Alter von 36,9 Jahren. 95 % der Betroffenen hatten ein Handekzem, das morphologisch häufig als dyshidrotischer Typ dominierte. Ätiologisch bestand in vielen Fällen ein Mischbild aus irritativem, atopischem und kontaktallergischem Handekzem, wobei insgesamt die irritativen Kontaktekzeme (43 %) dominierten. 68 % der Teilnehmer hatten eine atopische Hautdiathese. Das Seminar wird von den Teilnehmern durchgehend als gut eingestuft. Positiv sind sogenannte Seiteneffekte wie z. B. die Weitergabe des Erlernten an Arbeitskollegen, Familienmitglieder und Freunde.

Schlußfolgerungen: Berufsdermatologische Untersuchungen und Beratungen werden bisher nur lückenhaft durchgeführt sowie Hautschutz‐ und Hautpflegemaßnahmen noch nicht ausreichend umgesetzt und angewandt. Es ist anzustreben, Hautschutzseminare zukünftig auch für andere hautgefährdende Berufszweige anzubieten.
Photon detection by a cryogenic InSb detector
Authors: Kanno Ikuo , Hishiki Shigeomi , Sugiura Osamu , Xiang Ruifei , Nakamura Tatsuya , Katagiri Masaki
Published: January 2005

Gamma rays of Am241 were measured by a Schottky type undoped InSb detector at 4.2K. Although a photopeak was not observed, the signals of gamma rays were clearly separated from noises.
Decontamination of biological warfare agents by a microwave plasma torch
Authors: Lai Wilson , Lai Henry , Kuo Spencer P. , Tarasenko Olga , Levon Kalle
Published: January 2005

A portable arc-seeded microwave plasma torch running stably with airflow is described and applied for the decontamination of biological warfare agents. Emission spectroscopy of the plasma torch indicated that this torch produced an abundance of reactive atomic oxygen that could effectively oxidize biological agents. Bacillus cereus was chosen as a simulant of Bacillus anthracis spores for biological agent in the decontamination experiments. Decontamination was performed with the airflow rate of 0.393l∕s, corresponding to a maximum concentration of atomic oxygen produced by the torch. The experimental results showed that all spores were killed in less than 8 s at 3 cm distance, 12 s at 4 cm distance, and 16 s at 5 cm distance away from the nozzle of the torch.
Impact of oxygen on carbon precipitation in polycrystalline ribbon silicon
Authors: Lu Jinggang , Rozgonyi George , Schönecker Axel , Gutjahr Astrid , Liu Zhenxian
Published: January 2005

This article reports experimental evidence for the effect of oxygen on carbon precipitation in polycrystalline ribbon silicon. Four sets of wafers subject to various heat treatments have been examined by infrared spectroscopy. It is found that carbon precipitation in an oxygen-containing wafer consists of two distinct steps, namely, an initial rapid oxygen–carbon coprecipitation in the very first hour annealing, followed by slow precipitation during subsequent prolonged annealing. A high oxygen content enhances carbon precipitation throughout the two steps. It is shown that the formation of interstitial carbon in the presence of excess silicon self-interstitials generated during oxygen precipitation plays an important role in increasing the carbon precipitation rate in the first hour annealing. Because of the absence of interstitial injection during the following slow precipitation process, the enhancement effect of oxygen can only arise from an increase in precipitation sites. It is proposed that the oxygen–carbon coprecipitates formed in the very first hour annealing provide sites for continuous carbon precipitation. This explains why carbon impurities precipitate faster in a high oxygen-containing wafer, even after removal of all the interstitial oxygen from the silicon matrix.
Enhanced photoluminescence of Ga2O3:Dy3+ phosphor films by Li+ doping
Authors: Pang M. L. , Shen W. Y. , Lin J.
Published: January 2005

Ga 2 O 3 : Dy 3 + and Li+-doped Ga2O3:Dy3+ phosphor films were prepared by a Pechini sol-gel process. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), atomic force microscopy, and photoluminescence (PL) spectra as well as lifetimes were used to characterize the resulting thin films (and powder samples for comparison). The results of the FTIR and XRD indicated that the films began to crystallize at 700 °C and the crystallinity increased with the elevation of annealing temperatures. Upon excitation into band gap of β-Ga2O3 at 250 nm, the Ga2O3:Dy3+ and Li+-doped Ga2O3:Dy3+ films show similar emission spectra, which mainly consist of the characteristic emission bands of Dy3+ ions (F9∕24–H13∕26 transition at 492 nm and F9∕24–H15∕26 transition at 580 nm) due to an efficient energy transfer from the β-Ga2O3 host lattice to the doped Dy3+ ions. The incorporation of Li+ ions into the Ga2O3:Dy3+ film have enlarged the grain size and enhanced the photoluminescence intensities. The highest emission intensity was observed in Ga1.86Dy0.04O3:0.1Li+ film, whose PL intensity is more than twice that of the Ga1.96Dy0.04O3 film.
tp53
mutant zebrafish develop malignant peripheral nerve sheath tumors
Authors: Berghmans Stéphane , Murphey Ryan D. , Wienholds Erno , Neuberg Donna , Kutok Jeffery L. , Fletcher Christopher D. M. , Morris John P. , Liu Ting Xi , Schulte-Merker Stefan , Kanki John P. , Plasterk Ronald , Zon Leonard I. , Look A. Thomas
Published: January 2005

TP53
is the most frequently mutated tumor suppressor gene in human cancer, with nearly 50% of all tumors exhibiting a loss-of-function mutation. To further elucidate the genetic pathways involving
TP53
and cancer, we have exploited the zebrafish, a powerful vertebrate model system that is amenable to whole-genome forward-genetic analysis and synthetic-lethal screens. Zebrafish lines harboring missense mutations in the
tp53
DNA-binding domain were identified by using a target-selected mutagenesis strategy. Homozygous mutant fish from two of these lines were viable and exhibited mutations similar to those found in human cancers (
tp53
N168K
and
tp53
M214K
). Although homozygous
tp53
N168K
mutants were temperature-sensitive and suppressed radiation-induced apoptosis only at 37°C, cells in the
tp53
M214K
embryos failed to undergo apoptosis in response to γ radiation at both 28 and 37°C. Unlike wild-type control embryos, irradiated
tp53
M214K
embryos also failed to up-regulate
p21
and did not arrest at the G
1
/S checkpoint. Beginning at 8.5 months of age, 28% of
tp53
M214K
mutant fish developed malignant peripheral nerve sheath tumors. In addition to providing a model for studying the molecular pathogenic pathways of malignant peripheral nerve sheath tumors, these mutant zebrafish lines provide a unique platform for modifier screens to identify genetic mutations or small molecules that affect
tp53
-related pathways, including apoptosis, cell-cycle delay, and tumor suppression.
Pea DNA helicase 45 overexpression in tobacco confers high salinity tolerance without affecting yield
Authors: Sanan-Mishra Neeti , Pham Xuan Hoi , Sopory Sudhir K. , Tuteja Narendra
Published: January 2005

Salt tolerance is an important trait that is required to overcome salinity-induced reduction in plant productivity. We have reported previously the isolation of a pea DNA helicase 45 (PDH45) that exhibits striking homology with the eukaryotic translation initiation factor eIF-4A. Here, we report that
PDH45
mRNA is induced in pea seedlings in response to high salt, and its overexpression driven by a constitutive cauliflower mosaic virus-
35
S promoter in tobacco plants confers salinity tolerance, thus suggesting a previously undescribed pathway for manipulating stress tolerance in crop plants. The T
0
transgenic plants showed high levels of PDH45 protein in normal and stress conditions, as compared with WT plants. The T
0
transgenics also showed tolerance to high salinity as tested by a leaf disk senescence assay. The T
1
transgenics were able to grow to maturity and set normal viable seeds under continuous salinity stress without any reduction in plant yield in terms of seed weight. Measurement of Na
+
ions in different parts of the plant showed higher accumulation in the old leaves and negligible accumulation in seeds of T
1
transgenic lines as compared with the WT plants. The possible mechanism of salinity tolerance is discussed. Overexpression of PDH45 provides a possible example of the exploitation of DNA/RNA unwinding pathways for engineering salinity tolerance without affecting yield in crop plants.
Molecular basis for amyloid fibril formation and stability
Authors: Makin O. Sumner , Atkins Edward , Sikorski Pawel , Johansson Jan , Serpell Louise C.
Published: January 2005

The molecular structure of the amyloid fibril has remained elusive because of the difficulty of growing well diffracting crystals. By using a sequence-designed polypeptide, we have produced crystals of an amyloid fiber. These crystals diffract to high resolution (1 Å) by electron and x-ray diffraction, enabling us to determine a detailed structure for amyloid. The structure reveals that the polypeptides form fibrous crystals composed of antiparallel β-sheets in a cross-β arrangement, characteristic of all amyloid fibers, and allows us to determine the side-chain packing within an amyloid fiber. The antiparallel β-sheets are zipped together by means of π-bonding between adjacent phenylalanine rings and salt-bridges between charge pairs (glutamic acid–lysine), thus controlling and stabilizing the structure. These interactions are likely to be important in the formation and stability of other amyloid fibrils.
The crystal structure of human adenylate kinase 6: An adenylate kinase localized to the cell nucleus
Authors: Ren Hui , Wang Liya , Bennett Matthew , Liang Yuhe , Zheng Xiaofeng , Lu Fei , Li Lanfen , Nan Jie , Luo Ming , Eriksson Staffan , Zhang Chuanmao , Su Xiao-Dong
Published: January 2005

Adenylate kinases (AKs) play important roles in nucleotide metabolism in all organisms and in cellular energetics by means of phosphotransfer networks in eukaryotes. The crystal structure of a human AK named AK6 was determined by in-house sulfur single-wavelength anomalous dispersion phasing methods and refined to 2.0-Å resolution with a free
R
factor of 21.8%. Sequence analyses revealed that human AK6 belongs to a distinct subfamily of AKs present in all eukaryotic organisms sequenced so far. Enzymatic assays show that human AK6 has properties similar with other AKs, particularly with AK5. Fluorescence microscopy showed that human AK6 is localized predominantly to the nucleus of HeLa cells. The identification of a nuclear-localized AK sheds light on nucleotide metabolism in the nucleus and the energetic communication between mitochondria and nucleus by means of phosphotransfer networks.
Optical tracking of organically modified silica nanoparticles as DNA carriers: A nonviral, nanomedicine approach for gene delivery
Authors: Roy Indrajit , Ohulchanskyy Tymish Y. , Bharali Dhruba J. , Pudavar Haridas E. , Mistretta Ruth A. , Kaur Navjot , Prasad Paras N.
Published: January 2005

This article reports a multidisciplinary approach to produce fluorescently labeled organically modified silica nanoparticles as a nonviral vector for gene delivery and biophotonics methods to optically monitor intracellular trafficking and gene transfection. Highly monodispersed, stable aqueous suspensions of organically modified silica nanoparticles, encapsulating fluorescent dyes and surface functionalized by cationic-amino groups, are produced by micellar nanochemistry. Gel-electrophoresis studies reveal that the particles efficiently complex with DNA and protect it from enzymatic digestion of DNase 1. The electrostatic binding of DNA onto the surface of the nanoparticles, due to positively charged amino groups, is also shown by intercalating an appropriate dye into the DNA and observing the Förster (fluorescence) resonance energy transfer between the dye (energy donor) intercalated in DNA on the surface of nanoparticles and a second dye (energy acceptor) inside the nanoparticles. Imaging by fluorescence confocal microscopy shows that cells efficiently take up the nanoparticles
in vitro
in the cytoplasm, and the nanoparticles deliver DNA to the nucleus. The use of plasmid encoding enhanced GFP allowed us to demonstrate the process of gene transfection in cultured cells. Our work shows that the nanomedicine approach, with nanoparticles acting as a drug-delivery platform combining multiple optical and other types of probes, provides a promising direction for targeted therapy with enhanced efficacy as well as for real-time monitoring of drug action.
An embryonic poly(A)-binding protein (ePAB) is expressed in mouse oocytes and early preimplantation embryos
Authors: Seli Emre , Lalioti Maria D. , Flaherty Sean M. , Sakkas Denny , Terzi Nihal , Steitz Joan A.
Published: January 2005

Gene expression during oocyte maturation, fertilization, and early embryo development until zygotic gene activation is regulated mainly by translational activation of maternally derived mRNAs. This process requires the presence of a poly(A)-binding protein. However, the cytoplasmic somatic cell poly(A)-binding protein (PABP1) is not expressed until later in embryogenesis. We recently identified an embryonic poly(A)-binding protein (ePAB) in
Xenopus.
ePAB is the predominant cytoplasmic PABP in
Xenopus
oocytes and early embryos and prevents deadenylation of mRNAs, suggesting its importance in the regulation of gene expression during early
Xenopus
development. Here we report the identification of the mouse ortholog of
Xenopus
ePAB. The mouse ePAB gene on chromosome 2 contains 14 exons that specify an alternatively spliced mRNA encoding a protein of 608 or 561 aa with ≈65% identity to
Xenopus
ePAB. Mouse ePAB mRNA is expressed in ovaries and testis but not in somatic tissues.
In situ
hybridization localizes ePAB RNA to oocytes and confirms its absence from surrounding somatic cells in the mouse ovary. During early development, mouse ePAB is expressed in prophase I and metaphase II oocytes and one-cell and two-cell embryos and then becomes undetectable in four-or-more-cell embryos. In contrast, PABP1 mRNA expression is minimal in oocytes and early embryos until the eight-cell stage when it increases, becoming predominant at the blastocyst stage. The expression of mouse ePAB before zygotic gene activation argues for its importance in translational activation of maternally derived mRNAs during mammalian oocyte and early preimplantation embryo development.
Conformational changes during the nanosecond-to-millisecond unfolding of ubiquitin
Authors: Chung Hoi Sung , Khalil Munira , Smith Adam W. , Ganim Ziad , Tokmakoff Andrei
Published: January 2005

Steady-state and transient conformational changes upon the thermal unfolding of ubiquitin were investigated with nonlinear IR spectroscopy of the amide I vibrations. Equilibrium temperature-dependent 2D IR spectroscopy reveals the unfolding of the β-sheet of ubiquitin through the loss of cross peaks formed between transitions arising from delocalized vibrations of the β-sheet. Transient unfolding after a nanosecond temperature jump is monitored with dispersed vibrational echo spectroscopy, a projection of the 2D IR spectrum. Whereas the equilibrium study follows a simple two-state unfolding, the transient experiments observe complex relaxation behavior that differs for various spectral components and spans 6 decades in time. The transient behavior can be separated into fast and slow time scales. From 100 ns to 0.5 ms, the spectral features associated with β-sheet unfolding relax in a sequential, nonexponential manner, with time constants of 3 μs and 80 μs. By modeling the amide I vibrations of ubiquitin, this observation is explained as unfolding of the less stable strands III–V of the β-sheet before unfolding of the hairpin that forms part of the hydrophobic core. This downhill unfolding is followed by exponential barrier-crossing kinetics on a 3-ms time scale.
p107 inhibits G1 to S phase progression by down-regulating expression of the F-box protein Skp2
Authors: Rodier Geneviève , Makris Constantin , Coulombe Philippe , Scime Anthony , Nakayama Keiko , Nakayama Keiichi I. , Meloche Sylvain
Published: January 2005

Cell cycle progression is negatively regulated by the pocket proteins pRb, p107, and p130. However, the mechanisms responsible for this inhibition are not fully understood. Here, we show that overexpression of p107 in fibroblasts inhibits Cdk2 activation and delays S phase entry. The inhibition of Cdk2 activity is correlated with the accumulation of p27, consequent to a decreased degradation of the protein, with no change of Thr187 phosphorylation. Instead, we observed a marked decrease in the abundance of the F-box receptor Skp2 in p107-overexpressing cells. Reciprocally, Skp2 accumulates to higher levels in p107−/− embryonic fibroblasts. Ectopic expression of Skp2 restores p27 down-regulation and DNA synthesis to the levels observed in parental cells, whereas inactivation of Skp2 abrogates the inhibitory effect of p107 on S phase entry. We further show that the serum-dependent increase in Skp2 half-life observed during G1 progression is impaired in cells overexpressing p107. We propose that p107, in addition to its interaction with E2F, inhibits cell proliferation through the control of Skp2 expression and the resulting stabilization of p27.
CLASP1 and CLASP2 bind to EB1 and regulate microtubule plus-end dynamics at the cell cortex
Authors: Mimori-Kiyosue Yuko , Grigoriev Ilya , Lansbergen Gideon , Sasaki Hiroyuki , Matsui Chiyuki , Severin Fedor , Galjart Niels , Grosveld Frank , Vorobjev Ivan , Tsukita Shoichiro , Akhmanova Anna
Published: January 2005

CLIP-associating protein (CLASP) 1 and CLASP2 are mammalian microtubule (MT) plus-end binding proteins, which associate with CLIP-170 and CLIP-115. Using RNA interference in HeLa cells, we show that the two CLASPs play redundant roles in regulating the density, length distribution and stability of interphase MTs. In HeLa cells, both CLASPs concentrate on the distal MT ends in a narrow region at the cell margin. CLASPs stabilize MTs by promoting pauses and restricting MT growth and shortening episodes to this peripheral cell region. We demonstrate that the middle part of CLASPs binds directly to EB1 and to MTs. Furthermore, we show that the association of CLASP2 with the cell cortex is MT independent and relies on its COOH-terminal domain. Both EB1- and cortex-binding domains of CLASP are required to promote MT stability. We propose that CLASPs can mediate interactions between MT plus ends and the cell cortex and act as local rescue factors, possibly through forming a complex with EB1 at MT tips.
Hydrogen peroxide as a signal controlling plant programmed cell death
Authors: Gechev Tsanko S. , Hille Jacques
Published: January 2005

Hydrogen peroxide (H2O2) has established itself as a key player in stress and programmed cell death responses, but little is known about the signaling pathways leading from H2O2 to programmed cell death in plants. Recently, identification of key regulatory mutants and near-full genome coverage microarray analysis of H2O2-induced cell death have begun to unravel the complexity of the H2O2 network. This review also describes a novel link between H2O2 and sphingolipids, two signals that can interplay and regulate plant cell death.
Mdm31 and Mdm32 are inner membrane proteins required for maintenance of mitochondrial shape and stability of mitochondrial DNA nucleoids in yeast
Authors: Dimmer Kai Stefan , Jakobs Stefan , Vogel Frank , Altmann Katrin , Westermann Benedikt
Published: January 2005

The MDM31 and MDM32 genes are required for normal distribution and morphology of mitochondria in the yeast Saccharomyces cerevisiae. They encode two related proteins located in distinct protein complexes in the mitochondrial inner membrane. Cells lacking Mdm31 and Mdm32 harbor giant spherical mitochondria with highly aberrant internal structure. Mitochondrial DNA (mtDNA) is instable in the mutants, mtDNA nucleoids are disorganized, and their association with Mmm1-containing complexes in the outer membrane is abolished. Mutant mitochondria are largely immotile, resulting in a mitochondrial inheritance defect. Deletion of either one of the MDM31 and MDM32 genes is synthetically lethal with deletion of either one of the MMM1, MMM2, MDM10, and MDM12 genes, which encode outer membrane proteins involved in mitochondrial morphogenesis and mtDNA inheritance. We propose that Mdm31 and Mdm32 cooperate with Mmm1, Mmm2, Mdm10, and Mdm12 in maintenance of mitochondrial morphology and mtDNA.