Publications by authors named "Franz Bauer"

21 Publications

  • Page 1 of 1

Author Correction: A semi-automated virtual workflow solution for the design and production of intraoral molding plates using additive manufacturing: the first clinical results of a pilot-study.

Sci Rep 2020 Mar 10;10(1):4726. Epub 2020 Mar 10.

Department of Oral and Maxillofacial Surgery, Technische Universität München, München, Germany.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-020-61778-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7062694PMC
March 2020

RapidNAM: Algorithm for the Semi-Automated Generation of Nasoalveolar Molding Device Designs for the Presurgical Treatment of Bilateral Cleft Lip and Palate.

IEEE Trans Biomed Eng 2020 05 12;67(5):1263-1271. Epub 2019 Aug 12.

Objective: Nasoalveolar molding (NAM) is an accepted presurgical treatment modality for newborns with cleft lip and palate (CLP). However, the therapy is time-consuming and requires high expertise. To facilitate the treatment, we reveal an algorithm for the automated generation of patient individual NAM devices for neonates with bilateral cleft lip and palate (BCLP) and present results of software validation.

Methods: The algorithm was implemented utilizing Python 2.7 and Blender 2.78a based on 17 digitized (3D-scanning) impressions of maxillae with BCLP. The algorithm segments alveolar structures, bridges clefts, and generates a series of NAM device designs, destined for 3D-printing for subsequent treatment. The datasets were used for first software tests. For validation, a follow-up study was carried out using six new, independent maxilla models. The generated NAM plate designs were examined regarding their potential clinical usability. Furthermore, a deviation analysis was carried out, which measured the plate models' and upper jaw models' surface deviations.

Results: Series of NAM devices were generated automatically in 21 out of 23 cases. We calculated an average surface deviation of 0.140 mm (SD: 0.016 mm). Four out of six plate series (follow-up trials) were assessed as probably usable with minor adjustments.

Conclusion: The algorithm generates 3D-printable series of NAM device designs reliably. We expect most of the series to be clinically usable and that the first plates of each series will fit the patients' maxillae.

Significance: The proposed algorithm has the potential to reduce the therapist's manual work and therefore time effort/costs related to NAM.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1109/TBME.2019.2934907DOI Listing
May 2020

Prenatal intrauterine maxillary development - An evaluation with three-dimensional ultrasound.

J Craniomaxillofac Surg 2019 Jul 30;47(7):1077-1082. Epub 2019 Jan 30.

Department of Oral and Maxillofacial Surgery, Technische Universität München, Germany; Helios Klinik München West, Germany.

Objectives: The aim of this prospective study was to investigate normal fetal maxillary development with volume ultrasound during the prenatal phase, for a better estimation of maxillary growth processes.

Methods: Some 210 3D volumes were obtained in two measurement series from 38 healthy women (gestational age: 19 to 31 weeks) using a GE Voluson™ E10 ultrasound system. Maxillary length and width were determined in the axial and sagittal planes. Clearly defined, reproducible landmarks were used for measurements. The results were correlated with gestational age and compared with previously reported studies.

Results: Total maxillary length ranged from 10.30 to 24.75 mm, total maxillary width from 13.65 to 37.30 mm in an observation period during the second trimester, with high reproducibility for all landmarks. All evaluation results showed steep growth with exponential character. Length growth was determined to be more dominant than width growth. Intra-rater correlation was evaluated to be almost perfect (ICC (3) > 0.8).

Conclusion: This study presents measurements of physiological fetal maxillary development. The defined landmarks proved to be representative for further investigations. This study serves as a baseline for a better understanding of fetal maxillary growth processes, and may be useful for standardising detection of malformations or intrauterine growth restrictions.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jcms.2019.01.029DOI Listing
July 2019

The absolute and relative effects of presurgical nasoalveolar moulding in bilateral cleft lip and palate patients compared with nasal growth in healthy newborns.

J Craniomaxillofac Surg 2019 Jul 11;47(7):1083-1091. Epub 2019 Feb 11.

Department of Oral and Maxillofacial Surgery, Technische Universität München, Germany. Electronic address:

Background: This study investigated the efficiency of nasoalveolar moulding (NAM) in patients presenting with bilateral cleft lip and palate (BCLP). It focused explicitly on nasal outcome and therefore made comparisons with healthy age-matched infants with normal nasal development.

Methods: Nasal impressions from 19 BCLP patients were analysed at the beginning and at the end of NAM treatment. In addition, nasal impressions from 32 healthy newborns were taken monthly for 4 months. The casts were digitalized and analysed, using defined anatomic landmarks, by two independent observers. Initial values were compared with outcome parameters at the end of NAM therapy and with the healthy cohort.

Results: NAM significantly elongated the columella in BCLP patients, with an increase of 106.5% versus 14.5% in healthy newborns. Nostril height showed significant expansion from 4.2 mm to 5.6 mm on the right side, and from 4.3 mm to 6.2 mm on the left side.

Conclusion: NAM significantly elongated columella length and increased nostril height. The comparison with healthy newborns showed the effectiveness of early cartilage moulding. Detailed knowledge about absolute and relative early nasal growth was gained. However, despite highly effective NAM treatment in BCLP, nasal dimensions will not reach healthy proportions.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jcms.2019.01.044DOI Listing
July 2019

Stress Distribution Patterns within Viscero- and Neurocranium during Nasoalveolar Molding: a Finite Element Analysis.

Plast Reconstr Surg Glob Open 2018 Jul 17;6(7):e1832. Epub 2018 Jul 17.

Department of Oral and Maxillofacial Surgery, Klinikum rechts der Isar, Technische Universität München, Germany.

Background: The purpose of this study was to evaluate the stress distribution patterns within the viscero- and neurocranium of neonates during nasoalveolar molding.

Methods: Finite element models of 3 different healthy neonates at different times of life (date of birth, 4 weeks, and 3.5 months) were generated on the basis of computed tomography scans. A validated workflow, including segmentation, meshing, setting of boundary conditions, and implementation of a bone density-dependent material model, was carried out for each model. A small and a large unilateral alveolar and hard palatal cleft were virtually cut in each model. The stress distribution pattern in each model was then analyzed by using Ansys APDL.

Results: Convergence analysis validated the results. The virtual experiments at the date of birth showed a stress pattern above a previously defined threshold value of 30,000 Pa in the ipsilateral naso-orbital-complex, frontal sinus, and the anterior fossa of the base of the skull, with von Mises values > 35,000 Pa. Stress patterns at the age of 4 weeks and 3.5 months showed reduced von Mises values at < 15,000 Pa.

Conclusions: Nasoalveolar molding therapy is a safe presurgical treatment modality without significant influence on the viscero- and neurocranium of neonates. Treatment, considering the stress distribution at the naso-orbital-complex and anterior fossa of the base of the skull, should begin in the second week of life, and treatment initiation of preterm infants should be adapted respectively.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/GOX.0000000000001832DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6110680PMC
July 2018

Facilitating CAD/CAM nasoalveolar molding therapy with a novel click-in system for nasal stents ensuring a quick and user-friendly chairside nasal stent exchange.

Sci Rep 2018 08 14;8(1):12084. Epub 2018 Aug 14.

Institute of Medical and Polymer Engineering, Technische Universität München, München, Germany.

Nasoalveolar molding (NAM) aims to improve nasal symmetry with a nasal stent in cleft lip and palate (CLP) patients. When plates have to be exchanged because of dentoalveolar growth or cleft reduction, the nasal stent has to be mounted onto a new plate. This procedure elongates visiting hours for patients and parents or requires second treatment sessions. This study introduces a quick-lock additive manufacturing solution for chairside nasal stent exchange called RapidNAM. A novel taping retention pin has been designed that enables nasal stent insertion. Patients with unilateral CLP were included in this study. Plaster models were digitalized and measured by two independent observers. Two methods of CAD/CAM-molding therapies were compared: (i) conventional adhesion of a nasal stent (CAD/CAM NAM); (ii) quick-lock system in which the nasal stent was transferred to another plate (RapidNAM). CAD/CAM NAM and its refinement RapidNAM significantly increased the cleft-side nasal height and tilted the nose towards symmetry. The quick-lock system minimizes wire adaptations, since the pre-existing stent can be reused. The new nasal stent development seems a feasible solution to minimize visiting hours but with clinically satisfactory results. This new nasal stent system combines traditional elements of NAM with CAD/CAM-technology.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-018-29960-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6092331PMC
August 2018

A semi-automated virtual workflow solution for the design and production of intraoral molding plates using additive manufacturing: the first clinical results of a pilot-study.

Sci Rep 2018 08 7;8(1):11845. Epub 2018 Aug 7.

Department of Oral and Maxillofacial Surgery, Technische Universität München, München, Germany.

Computer-aided design and computer-aided manufacturing (CAD/CAM) technology has been implemented in the treatment of cleft lip and palates (CLP) by several research groups. This pilot study presents a technique that combines intraoral molding with a semi-automated plate generation and 3D-printing. The clinical results of two intraoral molding approaches are compared. This is the first clinical investigation of semi-automated intraoral molding. Our study included newborns with unilateral CLP. Plaster models were digitalized and measured by two independent observers. Two methods of CAD/CAM-assisted intraoral molding were compared: (i) stepwise manual design of molding plates (conventional CAD/CAM-intraoral molding) and (ii) a semi-automated approach with an automated detection of alveolar ridges (called RapidNAM) assisted by a graphical user interface (GUI). Both approaches significantly narrowed the clefts and resulted in a harmonic alveolar crest alignment. The GUI was easy to use and generated intraoral molding devices within minutes. The presented design solution is an efficient technical refinement with good clinical results. The semi-automated plate generation with a feasible GUI is fast but allows individual adaptations. This promising technique might facilitate and foster the more widespread use of CAD/CAM-technology in intraoral molding therapy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-018-29959-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6081393PMC
August 2018

The onset of star formation 250 million years after the Big Bang.

Nature 2018 05 16;557(7705):392-395. Epub 2018 May 16.

Department of Physics, Graduate School of Science, The University of Tokyo, Tokyo, Japan.

A fundamental quest of modern astronomy is to locate the earliest galaxies and study how they influenced the intergalactic medium a few hundred million years after the Big Bang. The abundance of star-forming galaxies is known to decline from redshifts of about 6 to 10, but a key question is the extent of star formation at even earlier times, corresponding to the period when the first galaxies might have emerged. Here we report spectroscopic observations of MACS1149-JD1 , a gravitationally lensed galaxy observed when the Universe was less than four per cent of its present age. We detect an emission line of doubly ionized oxygen at a redshift of 9.1096 ± 0.0006, with an uncertainty of one standard deviation. This precisely determined redshift indicates that the red rest-frame optical colour arises from a dominant stellar component that formed about 250 million years after the Big Bang, corresponding to a redshift of about 15. Our results indicate that it may be possible to detect such early episodes of star formation in similar galaxies with future telescopes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41586-018-0117-zDOI Listing
May 2018

A density cusp of quiescent X-ray binaries in the central parsec of the Galaxy.

Nature 2018 04;556(7699):70-73

Columbia Astrophysics Laboratory, Columbia University, 550 West 120th Street, Room 1027, New York, New York 10027, USA.

The existence of a 'density cusp'-a localized increase in number-of stellar-mass black holes near a supermassive black hole is a fundamental prediction of galactic stellar dynamics. The best place to detect such a cusp is in the Galactic Centre, where the nearest supermassive black hole, Sagittarius A*, resides. As many as 20,000 black holes are predicted to settle into the central parsec of the Galaxy as a result of dynamical friction; however, so far no density cusp of black holes has been detected. Low-mass X-ray binary systems that contain a stellar-mass black hole are natural tracers of isolated black holes. Here we report observations of a dozen quiescent X-ray binaries in a density cusp within one parsec of Sagittarius A*. The lower-energy emission spectra that we observed in these binaries is distinct from the higher-energy spectra associated with the population of accreting white dwarfs that dominates the central eight parsecs of the Galaxy. The properties of these X-ray binaries, in particular their spatial distribution and luminosity function, suggest the existence of hundreds of binary systems in the central parsec of the Galaxy and many more isolated black holes. We cannot rule out a contribution to the observed emission from a population (of up to about one-half the number of X-ray binaries) of rotationally powered, millisecond pulsars. The spatial distribution of the binary systems is a relic of their formation history, either in the stellar disk around Sagittarius A* (ref. 7) or through in-fall from globular clusters, and constrains the number density of sources in the modelling of gravitational waves from massive stellar remnants, such as neutron stars and black holes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/nature25029DOI Listing
April 2018

Establishment of a finite element model of a neonate's skull to evaluate the stress pattern distribution resulting during nasoalveolar molding therapy of cleft lip and palate patients.

J Craniomaxillofac Surg 2018 Apr 2;46(4):660-667. Epub 2018 Feb 2.

Department of Oral and Maxillofacial Surgery, Klinikum rechts der Isar, Technische Universität München, Germany.

Nasoalveolar Molding (NAM) is associated with ambivalent acceptance regarding effectiveness and unknown long-term results. Our purpose was to analyze the stress distribution patterns within the viscero- and neurocranium of neonates during the first phase of NAM therapy. A finite element (FE) model of a healthy four-week-old neonate was generated, derived from a computed tomography scan allowing the implementation of a bone-density-dependent material model. The influence of dental germs with variable material properties, the cleft width and area of expected force application were analyzed in a worst-case scenario. The resulting stress distribution patterns for each situation were analyzed using the software Ansys APDL. The established FE model was verified with a convergence analysis. Overall, stress patterns at the age of four weeks showed von Mises stress values below 60.000 Pa in the viscero- and neurocranium. The influences of the allocation of material properties for the dental germs, the area of force application, and the cleft width were negligible. A workflow to simulate the stress distribution and deformation in neonates attributable to various areas of force application has been established. Further analyses of the skulls of younger and older neonates are needed to describe the stress distribution patterns during NAM therapy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jcms.2018.01.015DOI Listing
April 2018

The close environments of accreting massive black holes are shaped by radiative feedback.

Nature 2017 09;549(7673):488-491

NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA.

The majority of the accreting supermassive black holes in the Universe are obscured by large columns of gas and dust. The location and evolution of this obscuring material have been the subject of intense research in the past decades, and are still debated. A decrease in the covering factor of the circumnuclear material with increasing accretion rates has been found by studies across the electromagnetic spectrum. The origin of this trend may be driven by the increase in the inner radius of the obscuring material with incident luminosity, which arises from the sublimation of dust; by the gravitational potential of the black hole; by radiative feedback; or by the interplay between outflows and inflows. However, the lack of a large, unbiased and complete sample of accreting black holes, with reliable information on gas column density, luminosity and mass, has left the main physical mechanism that regulates obscuration unclear. Here we report a systematic multi-wavelength survey of hard-X-ray-selected black holes that reveals that radiative feedback on dusty gas is the main physical mechanism that regulates the distribution of the circumnuclear material. Our results imply that the bulk of the obscuring dust and gas is located within a few to tens of parsecs of the accreting supermassive black hole (within the sphere of influence of the black hole), and that it can be swept away even at low radiative output rates. The main physical driver of the differences between obscured and unobscured accreting black holes is therefore their mass-normalized accretion rate.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/nature23906DOI Listing
September 2017

A prospective longitudinal study of postnatal dentoalveolar and palatal growth: The anatomical basis for CAD/CAM-assisted production of cleft-lip-palate feeding plates.

Clin Anat 2017 Oct 30;30(7):846-854. Epub 2017 May 30.

Department of Oral and Maxillofacial Surgery, Technische Universität München, Munich, Germany.

This study describes the dentoalveolar and palatal growth during the first months of life. Knowledge concerning this development is essential to avoid unwanted events such as mucosal ulcerations or restriction of growth when cleft-lip and palate (CLP) patients are treated. The results involve the generation of CAD/CAM CLP-feeding plates. Intraoral impressions from 32 healthy newborns were taken monthly for 5 months, supplemented by measurements of body weight, length, and occipital-frontal head circumference. The casts were digitalized, and two observers manually selected defined anatomical landmarks on virtual 3-D models. The distances between these landmarks were evaluted. Statistical analysis included an inter-rater agreement analysis and the determination of growth. In total, 213 casts were analyzed, with 65 models excluded because of inaccuracies in impression-taking or cast production. Overall longitudinal growth was 20.3%, whereas transversal growth reached a maximum of 21.1%. Vertical growth was 32.4% at the tuberal level. On the basis of these results, a semiautomated series of feeding plates allowing for monthly expansion could be generated. The acquired data serve as a useful reference for other pediatric and orthofacial investigations and treatments. One such application is the automated, fully virtual manufacture of CLP-feeding plates based on only one impression-taking. Our data reveal when caution is needed to prevent ulceration. The series of plates generated can minimize the time-consuming impression-taking and the production of further plaster models. The method of measurement is suitable for documentary purposes. Clin. Anat. 30:846-854, 2017. © 2017 Wiley Periodicals, Inc.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/ca.22892DOI Listing
October 2017

RapidNAM: generative manufacturing approach of nasoalveolar molding devices for presurgical cleft lip and palate treatment.

Biomed Tech (Berl) 2017 Aug;62(4):407-414

.

Nasoalveolar molding (NAM) is an accepted treatment strategy in presurgical cleft therapy. The major drawbacks of the treatment listed in the literature relate to the time of the treatment and the coordination of the required interdisciplinary team of therapists, parents, and patients. To overcome these limitations, we present the automated RapidNAM concept that facilitates the design and manufacturing process of NAM devices, and that allows the virtual modification and subsequent manufacture of the devices in advance, with a growth prediction factor adapted to the patient's natural growth. The RapidNAM concept involves (i) the prediction of three trajectories that envelope the fragmented alveolar segments with the goal to mimic a harmonic arch, (ii) the extrusion from the larger toward the smaller alveolar segment along the envelope curves toward the harmonic upper alveolar arch, and (iii) the generation of the NAM device with a ventilation hole, fixation pin, and fixation points for the nasal stents. A feasibility study for a vector-based approach was successfully conducted for unilateral and bilateral cleft lip and palate (CLP) patients. A comparison of the modified target models with the reference target models showed similar results. For further improvement, the number of landmarks used to modify the models was increased by a curve-based approach.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1515/bmt-2016-0035DOI Listing
August 2017

Pitfalls and solutions in virtual design of nasoalveolar molding plates by using CAD/CAM technology--A preliminary clinical study.

J Craniomaxillofac Surg 2016 Apr 14;44(4):453-9. Epub 2016 Jan 14.

Department of Oral and Maxillofacial Surgery, Technische Universität München, Germany. Electronic address:

Purpose: Computer-assisted design and computer-aided manufacturing (CAD/CAM) technology in nasoalveolar molding (NAM) should save time and manpower and reduce family input in cases of cleft lip and palate.

Material And Methods: Intraoral casts from 12 infants with complete unilateral cleft lip and palate were taken immediately after birth (T1) and after (T2) NAM treatment, digitalized, and transformed into STL data. The infants were randomized into Group 1 (n = 6) receiving conventional NAM treatment or Group 2 receiving CAD/CAM NAM (n = 6). We analyzed the following variables by using Geomagic software: intersegmental alveolar distance (ISAD); intersegmental lip distance (ISLD); nostril height cleft/noncleft (NHc/nc); nasal width cleft/noncleft (NWn/nc); and columella deviation angle (CDA).

Results: In both groups, all variables except NHnc and NWnc were changed significantly between T1 and T2. The analysis of the mean differences of the variables in Group 1 and 2 showed no significant differences, with a comparable incidence of clinical alterations such as skin or mucosal irritations.

Conclusion: NAM plates can be produced virtually by using CAD/CAM technology. The CAD/CAM NAM results show no significant differences from the conventional technique. We present our clinically usable virtual CAD/CAM workflow for producing a basic NAM plate.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jcms.2016.01.008DOI Listing
April 2016

Presurgical Nasoalveolar Molding for Cleft Lip and Palate: The Application of Digitally Designed Molds.

Plast Reconstr Surg 2016 05;137(5):903e-904e

Department of Mechanical Engineering, Technische Universität München, Munich, Germany.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/PRS.0000000000002057DOI Listing
May 2016

Extended hard-X-ray emission in the inner few parsecs of the Galaxy.

Nature 2015 Apr;520(7549):646-9

Space Science Laboratory, UC Berkeley, 7 Gauss Way, Berkeley, California 94720, USA.

The Galactic Centre hosts a puzzling stellar population in its inner few parsecs, with a high abundance of surprisingly young, relatively massive stars bound within the deep potential well of the central supermassive black hole, Sagittarius A* (ref. 1). Previous studies suggest that the population of objects emitting soft X-rays (less than 10 kiloelectronvolts) within the surrounding hundreds of parsecs, as well as the population responsible for unresolved X-ray emission extending along the Galactic plane, is dominated by accreting white dwarf systems. Observations of diffuse hard-X-ray (more than 10 kiloelectronvolts) emission in the inner 10 parsecs, however, have been hampered by the limited spatial resolution of previous instruments. Here we report the presence of a distinct hard-X-ray component within the central 4 × 8 parsecs, as revealed by subarcminute-resolution images in the 20-40 kiloelectronvolt range. This emission is more sharply peaked towards the Galactic Centre than is the surface brightness of the soft-X-ray population. This could indicate a significantly more massive population of accreting white dwarfs, large populations of low-mass X-ray binaries or millisecond pulsars, or particle outflows interacting with the surrounding radiation field, dense molecular material or magnetic fields. However, all these interpretations pose significant challenges to our understanding of stellar evolution, binary formation, and cosmic-ray production in the Galactic Centre.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/nature14353DOI Listing
April 2015

Distance measurement in middle ear surgery using a telemanipulator.

Med Image Comput Comput Assist Interv 2011 ;14(Pt 1):41-8

Institute of Microtechnology and Medical Device Technology (MiMed), Technische Universität München, Germany.

In this article, a new tool for the intraoperative measurement of distances within the middle ear by means of a micromanipulator is presented. The purpose of this work was to offer the surgeon a highly accurate tool for measuring the distances between two points in the 3D operational field. The tool can be useful in various operations; this article focuses, however, on measuring the distance between the stapes footplate and the long process of the incus of the middle ear. This distance is important for estimating the proper prosthesis length in stapedotomy for treating otosclerosis. We evaluated the system using a simplified mechanical model. Our results show that the system can measure distances with a maximum error of 0.04 mm.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3380533PMC
http://dx.doi.org/10.1007/978-3-642-23623-5_6DOI Listing
November 2011

Routine clinical use of alemtuzumab in patients with heavily pretreated B-cell chronic lymphocytic leukemia: a nation-wide retrospective study in Austria.

Cancer 2006 Nov;107(10):2408-16

Department of Internal Medicine, Division of Hemato-Oncology, University Hospital of Innsbruck, Innsbruck, Austria.

Background: In previous studies, alemtuzumab demonstrated considerable activity in patients with previously treated B-cell chronic lymphocytic leukemia (CLL), including fludarabine-refractory disease. In this retrospective study, the authors evaluated the benefit of alemtuzumab monotherapy in unselected patients with advanced, previously treated CLL who received treatment in the routine clinical setting.

Methods: Data were collected from 115 consecutive patients who received alemtuzumab therapy at 25 participating centers in Austria. Patients received a median of 3 prior lines of therapy (range, 1-11 prior lines of therapy), and 59% had fludarabine-refractory disease. Alemtuzumab was administered intravenously or subcutaneously with a planned schedule of 30 mg 3 times per week for up to 12 weeks. Patients received valacyclovir and trimethoprim/sulfamethoxazole for antiinfective prophylaxis.

Results: The overall response rate was 23%, with complete responses achieved in 5% of patients. Stable disease (SD) was achieved in 36% of patients. After a median follow-up of 17.5 months, the median overall survival (OS) was 20.2 months for all patients. A multivariate Cox regression analysis that included pretreatment baseline characteristics, response to therapy, and cumulative dose of alemtuzumab indicated that bulky lymphadenopathy, the administration of > r =3 previous therapies, and lack of response to alemtuzumab remained significant independent risk factors for inferior OS. The median OS had not been reached for responding patients. The median OS was 29.5 months for patients with SD and 10.8 months for patients with progressive disease.

Conclusions: The broad use of alemtuzumab in the routine clinical practice setting is feasible and active in unselected patients with pretreated CLL, and the current results confirmed the activity and safety of this agent, as reported in previously published clinical studies.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/cncr.22263DOI Listing
November 2006

The Chandra Deep Field-North Survey and the cosmic X-ray background.

Philos Trans A Math Phys Eng Sci 2002 Sep;360(1798):2057-75

Department of Astronomy and Astrophysics, 525 Davey Laboratory, The Pennsylvania State University, University Park, PA 16802, USA.

Chandra has performed a 1.4 Ms survey centred on the Hubble Deep Field-North (HDF-N), probing the X-ray Universe 55-550 times deeper than was possible with pre-Chandra missions. We describe the detected point and extended X-ray sources and discuss their overall multi-wavelength (optical, infrared, submillimetre and radio) properties. Special attention is paid to the HDF-N X-ray sources, luminous infrared starburst galaxies, optically faint X-ray sources and high-to-extreme redshift active galactic nuclei. We also describe how stacking analyses have been used to probe the average X-ray-emission properties of normal and starburst galaxies at cosmologically interesting distances. Finally, we discuss plans to extend the survey and argue that a 5-10 Ms Chandra survey would lay key groundwork for future missions such as XEUS and Generation-X.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1098/rsta.2002.1053DOI Listing
September 2002