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1.
Rev Sci Instrum ; 92(11): 113306, 2021 Nov 01.
Article in English | MEDLINE | ID: mdl-34852560

ABSTRACT

The upcoming commissioning of the superconducting (SC) continuous wave Helmholtz linear accelerators first of series cryomodule is going to demand precise alignment of the four internal SC cavities and two SC solenoids. For optimal results, a beam-based alignment method is used to reduce the misalignment of the whole cryomodule, as well as its individual components. A symmetric beam of low transverse emittance is required for this method, which is to be formed by a collimation system. It consists of two separate plates with milled slits, aligned in the horizontal and vertical direction. The collimation system and alignment measurements are proposed, investigated, and realized. The complete setup of this system and its integration into the existing environment at the GSI High Charge State Injector are presented, as well as the results of the recent reference measurements.

2.
J Eur Acad Dermatol Venereol ; 34(7): 1590-1594, 2020 Jul.
Article in English | MEDLINE | ID: mdl-31994253

ABSTRACT

BACKGROUND: For clinical care and research in vitiligo, photographs with the use of ultraviolet (UV) light or Wood's lamp are often made. Conventional cameras are insensitive to UV light. The use of a UV camera (UV photography) might improve image quality and ameliorate the assessment of target lesions in vitiligo. OBJECTIVES: To determine image quality and the validity and reliability of UV photography for the assessment of vitiligo target lesions. METHODS: Images of patients with vitiligo were made with UV photography and a conventional camera, and lesions were drawn on graph paper and transparent sheets. Image quality was scored by vitiligo experts and medical interns. The intraclass correlation coefficients (ICCs) of the lesion size determined with UV photography combined with digital surface measurement and the other techniques were hypothesized to be above 0.6. The ICCs between UV images taken by the same physician and between two different physicians were calculated for determining inter- and intra-reliability. RESULTS: In total, 31 lesions of 17 patients were included. Image quality was assessed as good or very good for 100% and 26% for UV photography and the conventional camera, respectively. ICCs of UV photography and the conventional camera, drawing the lesions on transparent sheets and graph paper, were 0.984, 0.988 and 0.983, respectively, confirming our hypotheses. The ICCs of the intra-rater and inter-rater were 0.999 and 0.998, respectively. CONCLUSIONS: The results of this study indicate that the use of UV photography for the assessment of vitiligo lesions improves image quality and is valid and reliable.


Subject(s)
Vitiligo , Humans , Photography , Reproducibility of Results , Ultraviolet Rays
3.
Nanotechnology ; 28(48): 485601, 2017 Dec 01.
Article in English | MEDLINE | ID: mdl-29105645

ABSTRACT

GaN microrods are used as a basis for subsequent InGaN quantum well (QW) and quantum dot deposition by metal-organic vapor phase epitaxy. The coverage of the shell along the sidewall of rods is dependent on the rod growth time and a complete coverage is obtained for shorter rod growth times. Transmission electron microscopy measurements are performed to reveal the structural properties of the InGaN layer on the sidewall facet and on the top facet. The presence of layers in the microrod and on the microrod surface will be discussed with respect to GaN and InGaN growth. A detailed model will be presented explaining the formation of multiple SiN layers and the partial and full coverage of the shell around the core. Cathodoluminescence measurements are performed to analyze the InGaN emission properties along the microrod and to study the microresonator properties of such hexagonal core-shell structures. High quality factor whispering gallery modes with [Formula: see text] are reported for the first time in a GaN microrod/InGaN non-polar QW core-shell geometry. The GaN/InGaN core-shell microrods are expected to be promising building blocks for low-threshold laser diodes and ultra-sensitive optical sensors.

4.
Nanotechnology ; 28(5): 055201, 2017 Feb 03.
Article in English | MEDLINE | ID: mdl-28008871

ABSTRACT

Nanotextured surfaces provide an ideal platform for efficiently capturing and emitting light. However, the increased surface area in combination with surface defects induced by nanostructuring e.g. using reactive ion etching (RIE) negatively affects the device's active region and, thus, drastically decreases device performance. In this work, the influence of structural defects and surface states on the optical and electrical performance of InGaN/GaN nanorod (NR) light emitting diodes (LEDs) fabricated by top-down RIE of c-plane GaN with InGaN quantum wells was investigated. After proper surface treatment a significantly improved device performance could be shown. Therefore, wet chemical removal of damaged material in KOH solution followed by atomic layer deposition of only 10 [Formula: see text] alumina as wide bandgap oxide for passivation were successfully applied. Raman spectroscopy revealed that the initially compressively strained InGaN/GaN LED layer stack turned into a virtually completely relaxed GaN and partially relaxed InGaN combination after RIE etching of NRs. Time-correlated single photon counting provides evidence that both treatments-chemical etching and alumina deposition-reduce the number of pathways for non-radiative recombination. Steady-state photoluminescence revealed that the luminescent performance of the NR LEDs is increased by about 50% after KOH and 80% after additional alumina passivation. Finally, complete NR LED devices with a suspended graphene contact were fabricated, for which the effectiveness of the alumina passivation was successfully demonstrated by electroluminescence measurements.

5.
J Cancer ; 7(13): 1861-1866, 2016.
Article in English | MEDLINE | ID: mdl-27698926

ABSTRACT

Introduction: FOLFIRINOX is emerging as new standard of care for fit patients with locally advanced pancreatic cancer (LAPC) and metastatic pancreatic cancer (MPC). However, some of the physicians are reluctant to use FOLFIRINOX due to high toxicity rates reported in earlier studies. We reviewed our experience with FOLFIRINOX in LAPC and MPC, focussing on dose adjustments, toxicity and efficacy. Methods: We reviewed all patients with LAPC or MPC treated with FOLFIRINOX in our institution between April 2011 and December 2015. Unresectability (stage III and IV) was determined by the institution's multidisciplinary team for pancreatic cancer. Results: Fifty patients (18 LAPC and 32 MPC) were enrolled, with a median age of 55 years (IQR 49-66) and WHO performance status of 0/1. FOLFIRINOX was given as first-line treatment in 82% of patients. Dose modifications were applied in 90% of patients. The median number of completed cycles was 8 (IQR 5-9). Grade 3-4 toxicity occurred in 52% and grade 5 toxicity in 2%. The response rate was 25% (12% in LAPC, 32% in MPC). Median overall survival and progression-free survival were 14.8 and 10.3 months in LAPC, and 9.0 and 5.9 months in MPC, respectively. Overall 1- and 2-year survival was 65% and 10% in LAPC and 40% and 5% in MPC. Within the LAPC group, 6 patients (33%) underwent local ablative therapy and 1 patient (6%) a resection, leading to a median survival of 21.8 months. Conclusion: FOLFIRINOX treatment with nearly routine dose modification was associated with acceptable toxicity rates, relatively high response rates and an encouraging overall survival.

6.
Sci Rep ; 6: 27553, 2016 06 10.
Article in English | MEDLINE | ID: mdl-27282258

ABSTRACT

The electrical behaviour of Schottky barrier diodes realized on vertically standing individual GaN nanorods and array of nanorods is investigated. The Schottky diodes on individual nanorod show highest barrier height in comparison with large area diodes on nanorods array and epitaxial film which is in contrast with previously published work. The discrepancy between the electrical behaviour of nanoscale Schottky diodes and large area diodes is explained using cathodoluminescence measurements, surface potential analysis using Kelvin probe force microscopy and 1ow frequency noise measurements. The noise measurements on large area diodes on nanorods array and epitaxial film suggest the presence of barrier inhomogeneities at the metal/semiconductor interface which deviate the noise spectra from Lorentzian to 1/f type. These barrier inhomogeneities in large area diodes resulted in reduced barrier height whereas due to the limited role of barrier inhomogeneities in individual nanorod based Schottky diode, a higher barrier height is obtained.

7.
Nano Lett ; 16(6): 3415-25, 2016 06 08.
Article in English | MEDLINE | ID: mdl-27187840

ABSTRACT

Vertically aligned hexagonal InN nanorods were grown mask-free by conventional metal-organic vapor phase epitaxy without any foreign catalyst. The In droplets on top of the nanorods indicate a self-catalytic vapor-liquid-solid growth mode. A systematic study on important growth parameters has been carried out for the optimization of nanorod morphology. The nanorod N-polarity, induced by high temperature nitridation of the sapphire substrate, is necessary to achieve vertical growth. Hydrogen, usually inapplicable during InN growth due to formation of metallic indium, and silane are needed to enhance the aspect ratio and to reduce parasitic deposition beside the nanorods on the sapphire surface. The results reveal many similarities between InN and GaN nanorod growth showing that the process despite the large difference in growth temperature is similar. Transmission electron microscopy, spatially resolved energy-dispersive X-ray spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and Raman spectroscopy have been performed to analyze the structural properties. Spatially resolved cathodoluminescence investigations are carried out to verify the optical activity of the InN nanorods. The InN nanorods are expected to be the material of choice for high-efficiency hot carrier solar cells.

8.
Plant Biol (Stuttg) ; 15(5): 789-97, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23627419

ABSTRACT

Inositol-containing phospholipids (phosphoinositides, PIs) control numerous cellular processes in eukaryotic cells. For plants, a key involvement of PIs has been demonstrated in the regulation of membrane trafficking, cytoskeletal dynamics and in processes mediating the adaptation to changing environmental conditions. Phosphatidylinositol-4,5-bisphosphate (PtdIns(4,5)P(2)) mediates its cellular functions via binding to various alternative target proteins. Such downstream targets of PtdIns(4,5)P(2) are characterised by the possession of specific lipid-binding domains, and binding of the PtdIns(4,5)P(2) ligand exerts effects on their activity or localisation. The large number of potential alternative binding partners - and associated cellular processes - raises the question how alternative or even contrapuntal effects of PtdIns(4,5)P(2) are orchestrated to enable cellular function. This article aims to provide an overview of recent insights and new views on how distinct functional pools of PtdIns(4,5)P(2) are generated and maintained. The emerging picture suggests that PtdIns(4,5)P(2) species containing different fatty acids influence the lateral mobility of the lipids in the membrane, possibly enabling specific interactions of PtdIns(4,5)P(2) pools with certain downstream targets. PtdIns(4,5)P(2) pools with certain functions might also be defined by protein-protein interactions of PI4P 5-kinases, which pass PtdIns(4,5)P(2) only to certain downstream partners. Individually or in combination, PtdIns(4,5)P(2) species and specific protein-protein interactions of PI4P 5-kinases might contribute to the channelling of PtdIns(4,5)P(2) signals towards specific functional effects. The dynamic nature of PI-dependent signalling complexes with specific functions is an added challenge for future studies of plant PI signalling.


Subject(s)
Fatty Acids/metabolism , Lipid Metabolism , Phosphatidylinositol 4,5-Diphosphate/metabolism , Phosphotransferases (Alcohol Group Acceptor)/metabolism , Plant Cells/physiology , Plant Proteins/metabolism , Plants/metabolism , Ligands , Plant Cells/metabolism , Signal Transduction
9.
Br J Cancer ; 107(8): 1409-17, 2012 Oct 09.
Article in English | MEDLINE | ID: mdl-23047593

ABSTRACT

BACKGROUND: Using mRNA expression-derived signatures as predictors of individual patient outcome has been a goal ever since the introduction of microarrays. Here, we addressed whether analyses of tumour mRNA at the exon level can improve on the predictive power and classification accuracy of gene-based expression profiles using neuroblastoma as a model. METHODS: In a patient cohort comprising 113 primary neuroblastoma specimens expression profiling using exon-level analyses was performed to define predictive signatures using various machine-learning techniques. Alternative transcript use was calculated from relative exon expression. Validation of alternative transcripts was achieved using qPCR- and cell-based approaches. RESULTS: Both predictors derived from the gene or the exon levels resulted in prediction accuracies >80% for both event-free and overall survival and proved as independent prognostic markers in multivariate analyses. Alternative transcript use was most prominently linked to the amplification status of the MYCN oncogene, expression of the TrkA/NTRK1 neurotrophin receptor and survival. CONCLUSION: As exon level-based prediction yields comparable, but not significantly better, prediction accuracy than gene expression-based predictors, gene-based assays seem to be sufficiently precise for predicting outcome of neuroblastoma patients. However, exon-level analyses provide added knowledge by identifying alternative transcript use, which should deepen the understanding of neuroblastoma biology.


Subject(s)
Exons/genetics , Neuroblastoma/genetics , Nuclear Proteins/genetics , Oncogene Proteins/genetics , Receptor, trkA/genetics , Cell Line, Tumor , Child, Preschool , Gene Expression Profiling , Humans , Infant , N-Myc Proto-Oncogene Protein , Neuroblastoma/mortality , Prognosis , RNA, Messenger , Risk Factors , Survival Analysis
10.
Magn Reson Med ; 62(3): 672-81, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19585599

ABSTRACT

The aim of this study was to propose and evaluate a methodology to analyze simultaneously acquired T2*-weighted dynamic susceptibility contrast (DSC) MRI and T(1)-weighted dynamic contrast enhanced (DCE) MRI data. Two generalized models of T2*-relaxation are proposed to account for tracer leakage, and a two-compartment exchange model is used to separate tracer in intra- and extravascular spaces. The methods are evaluated using data extracted from ROIs in three mice with subcutaneously implanted human colorectal tumors. Comparing plasma flow values obtained from DCE-MRI and DSC-MRI data defines a practical experimental paradigm to measure T2*-relaxivities, and reveals a factor of 15 between values in tissue and blood. Comparing mean transit time values obtained from DCE-MRI and DSC-MRI without leakage correction, indicates a significant reduction of susceptibility weighting in DSC-MRI during tracer leakage. A one-parameter gradient correction model provides a good approximation for this susceptibility loss, but redundancy of the parameter limits the practical potential of this model for DSC-MRI. Susceptibility loss is modeled more accurately with a variable T2*-relaxivity, which allows to extract new parameters that cannot be derived from DSC-MRI or DCE-MRI alone. They reflect the cellular and vessel geometry, and thus may lead to a more complete characterization of tissue structure.


Subject(s)
Colorectal Neoplasms/diagnosis , Colorectal Neoplasms/metabolism , Contrast Media/pharmacokinetics , Diffusion Magnetic Resonance Imaging/methods , Image Interpretation, Computer-Assisted/methods , Meglumine/pharmacokinetics , Organometallic Compounds/pharmacokinetics , Algorithms , Animals , Cell Line, Tumor , Computer Simulation , Humans , Image Enhancement/methods , Mice , Mice, Nude , Models, Biological , Reproducibility of Results , Sensitivity and Specificity
11.
Br J Cancer ; 99(6): 900-10, 2008 Sep 16.
Article in English | MEDLINE | ID: mdl-19238631

ABSTRACT

Drug targeting systems are nanometer-sized carrier materials designed for improving the biodistribution of systemically applied (chemo-) therapeutics. Reasoning that (I) the temporal and spatial interaction between systemically applied chemotherapy and clinically relevant fractionated radiotherapy is suboptimal, and that (II) drug targeting systems are able to improve the temporal and spatial parameters of this interaction, we have here set out to evaluate the potential of 'carrier-based radiochemotherapy'. N-(2-hydroxypropyl)methacrylamide (HPMA) copolymers were used as a model drug targeting system, doxorubicin and gemcitabine as model drugs, and the syngeneic and radio- and chemoresistant Dunning AT1 rat prostate carcinoma as a model tumour model. Using magnetic resonance imaging and gamma-scintigraphy, the polymeric drug carriers were first shown to circulate for prolonged periods of time, to localise to tumours both effectively and selectively, and to improve the tumour-directed delivery of low molecular weight agents. Subsequently, they were then shown to interact synergistically with radiotherapy, with radiotherapy increasing the tumour accumulation of the copolymers, and with the copolymers increasing the therapeutic index of radiochemotherapy (both for doxorubicin and for gemcitabine). Based on these findings, and on the fact that its principles are likely broadly applicable, we propose carrier-based radiochemotherapy as a novel concept for treating advanced solid malignancies.


Subject(s)
Acrylamides/therapeutic use , Diagnostic Imaging , Doxorubicin/therapeutic use , Iodine Radioisotopes/therapeutic use , Nanomedicine , Prostatic Neoplasms/drug therapy , Prostatic Neoplasms/radiotherapy , Acrylamides/pharmacokinetics , Animals , Antimetabolites, Antineoplastic/pharmacokinetics , Antimetabolites, Antineoplastic/therapeutic use , Combined Modality Therapy , Deoxycytidine/analogs & derivatives , Deoxycytidine/pharmacokinetics , Deoxycytidine/therapeutic use , Doxorubicin/pharmacokinetics , Drug Delivery Systems , Drug Resistance, Neoplasm , Gadolinium , Magnetic Resonance Imaging , Male , Maximum Tolerated Dose , Prostatic Neoplasms/diagnosis , Radiation Tolerance , Rats , Ribonucleotide Reductases/antagonists & inhibitors , Tissue Distribution , Gemcitabine
12.
Pneumologie ; 61(12): 759-63, 2007 Dec.
Article in German | MEDLINE | ID: mdl-18098068

ABSTRACT

When the sanatorium "Heidehaus" was founded on June 1, 1907 in the northern countryside of Hannover with Dr. Otto Ziegler as head about 120 beds for patients with tuberculosis were available. By 1914 about 200 patients were being treated by 4 physicians and 10 nurses. An operating theatre and a modern radiology unit were added in 1927. Shortly after the 2nd World War 400 patients with tuberculosis were hospitalised simultaneously. With the introduction of antituberculous triple drug treatment the number of patients dropped significantly. During this period many traditional facilities, used to care for patients with tuberculosis lost their financial basis and closed. However in the 1960s Prof. Schindler, the head of Heidehaus, widened the spectrum of the hospital into a modern chest hospital, focused on lung and airway diseases. In particular in the 1980s and 1990s this trend continued and 2 independent departments, i. e., pneumology and thoracic surgery were founded. In 2005 due to restructuring by the community of Hannover the "Heidehaus" moved completely and merged with another traditional hospital to become the new "Oststadt-Heidehaus". In its new surroundings both departments for pulmonary medicine and thoracic surgery offer a broad spectrum of modern thoracic medicine in cooperation with other disciplines.


Subject(s)
Health Resorts/history , Hospitals, Special/history , Rehabilitation Centers/history , Thoracic Surgery/history , Tuberculosis, Pulmonary/history , Germany , History, 20th Century , History, 21st Century , Humans
13.
Clin Oncol (R Coll Radiol) ; 16(3): 196-203, 2004 May.
Article in English | MEDLINE | ID: mdl-15191007

ABSTRACT

AIMS: Computed tomography (CT) is the reference technique for evaluating response to chemotherapy. The potential helpfulness of tumour markers is debated. MATERIALS AND METHODS: From March 1997 to January 1999, 91 consecutive patients receiving chemotherapy for metastatic colorectal carcinoma underwent whole-body spiral CT, estimates of anti-carcinoembryonic antigen (CEA) and CA19-9 every 8 weeks. RESULTS: CEA and CA19-9 levels were above normal in 78 (85.7%) and 61 (67.5%) patients, respectively. Tumour response evaluation according to the RECIST criteria was obtained at 8-week evaluation in 83 (91%) patients. The positive predictive values (PPV) for response of a decrease of the marker levels were 53.8 for CEA and 41.7 for CA19-9 using a 30% decrease threshold, and 60/52.2, respectively, using a 50% decrease threshold. Meaningful PPV values (> 90%) for progression of an increase of the marker levels were only obtained using the 200% increase threshold for CEA alone or a combination of CEA and CA 19-9. A 100% CEA increase between baseline and the 8-week evaluation was correlated to overall survival (P = 0.0023). The need for a radiological confirmation of tumour progression could be avoided by the systematic dosage of tumour markers at baseline and after 8 weeks of treatment only in a sub-population of 13% of the patients with a 200% increase of CEA or CA 19-9 at 8 weeks. CONCLUSIONS: CEA, CA 19-9, or both should be used with caution for tumour response evaluation to chemotherapy in addition to CT in metastatic colorectal carcinoma.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Biomarkers, Tumor/analysis , CA-19-9 Antigen/analysis , Carcinoembryonic Antigen/analysis , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/pathology , Aged , Disease Progression , Female , Humans , Male , Middle Aged , Predictive Value of Tests , Sensitivity and Specificity , Survival Analysis , Tomography, Spiral Computed , Treatment Outcome
14.
Pneumologie ; 58(5): 309-15, 2004 May.
Article in German | MEDLINE | ID: mdl-15162255

ABSTRACT

BACKGROUND: Respiratory tract infections significantly contribute to morbidity and mortality of cystic fibrosis patients. METHODS: We conducted a systematic literature review (Pubmed 01/1966 up to 09/2003) in order to present recommendations for the isolation of CF patients colonized with Burkholderia cepacia spp., Pseudomonas aeruginosa, Stenotrophomonas maltophilia and Alcaligenes spp. Evidence and quality of 64 publications dealing with pathogen transmission or isolation measurements of colonized patients were evaluated. RESULTS: B. cepacia spp. was dealt most often with and 35 of 36 authors recommended the isolation of patients colonized with this pathogen. Isolation of patients colonized with P. aeruginosa was proposed by 21 of 25 authors. Only 5 studies concerned S. maltophilia or Alcaligenes spp. CONCLUSIONS: A) B. cepacia spp. colonized patients need to get a single room for their own. B) P. aeruginosa colonized CF patients should be separated from non-colonized CF patients. C) Patients harbouring even multi drug resistant P. aeruginosa, S. maltophilia or Alcaligenes spp. may not share their room with immunocompromised patients and should also be isolated when treated in intensive care units.


Subject(s)
Cystic Fibrosis/therapy , Cystic Fibrosis/complications , Cystic Fibrosis/microbiology , Gram-Negative Bacterial Infections/prevention & control , Humans , Hygiene , PubMed
15.
Radiologe ; 43(6): 474-80, 2003 Jun.
Article in German | MEDLINE | ID: mdl-12827262

ABSTRACT

AIM: The suitability of dynamic parameters of the two-compartment model for detecting prostate carcinomas and its correlation with tumor microvascular density were evaluated. METHODS: The study included 43 patients with biopsy-proven prostate carcinoma: 28 were examined by 1.0-T MRI (Turbo-FLASH) and 15 by 1.5-T MRI (FLASH) with infusion of 0.1 mmol/kg Gd-DTPA. Signal time curves were parametrized with an open two-compartment model in amplitude and exchange rate constants (k(ep)). The microvascular density of resected prostate carcinomas was determined. RESULTS: The microvascular density in the tumors was significantly higher than in the adjacent healthy prostate tissue and correlated in both sequences with k(ep). Prostate carcinomas of the peripheral zone were demarcated by amplitude and k(ep). In the Turbo-FLASH sequence there was a significant difference between the tumor tissue and healthy peripheral zone in terms of k(ep) and in the FLASH sequence in terms of amplitude. CONCLUSION: Prostate carcinomas can be visualized with dynamic T1-weighted MR sequences using a two-compartment model. Moreover, the parameter k(ep) reveals the microvascular density in the tumor and can thus provide valuable clinical information for characterizing the tumors.


Subject(s)
Magnetic Resonance Imaging/methods , Prostatic Neoplasms/diagnosis , Biopsy , Contrast Media , Gadolinium DTPA , Humans , Immunohistochemistry , Male , Middle Aged , Prostate/blood supply , Prostate/pathology , Prostatectomy , Prostatic Neoplasms/blood supply , Prostatic Neoplasms/pathology , Prostatic Neoplasms/surgery
16.
Radiologe ; 43(6): 489-94, 2003 Jun.
Article in German | MEDLINE | ID: mdl-12827264

ABSTRACT

AIM: The aim of this study was the noninvasive characterization of prostate carcinoma orthotopically implanted in rats using Gd-DTPA-assisted dynamic MRI (dMRI) and proton magnetic resonance spectroscopy ((1)H-MRS). MATERIAL AND METHODS: After surgical exposure of the prostate, Dunning R3327 orthotopic prostate carcinoma was induced by injecting cells of the MAT-LyLu subline. Six rats were examined 5 and 14 days after tumor induction with dMRI and (1)H-MRS at 1.5 T. Six tumor-free rats served as controls. Using an open two-compartment model, the parameters A (amplitude) and k(ep) (exchange rate constants) were calculated from the signal time curves of the dMRI. The relative signal intensities (Cho/Cr) of the resonances of choline (Cho) and the creatine-phosphocreatine complex (Cr) were computed from the MR spectra. RESULTS: Already after 5 days, the tumors in the prostate could be clearly identified based on the decrease in signal intensity to T2w and increase of A and k(ep). High Cho/Cr levels and resonances of two lipid fractions (Lip(1) at 0.8-1.5 ppm and Lip(2) at 2.0-2.2 ppm) were observed by MRS in the highly necrotic tumors. CONCLUSIONS: The orthotopic rat prostate carcinoma model resembles human prostate carcinoma in regard to MR morphology, dMRI, and (1)H-MRS. The noninvasive characterization of perfusion and metabolism makes a comparative examination of different treatment modalities possible.


Subject(s)
Magnetic Resonance Imaging/methods , Magnetic Resonance Spectroscopy , Prostate/metabolism , Prostatic Neoplasms/diagnosis , Algorithms , Animals , Disease Models, Animal , Hemodynamics , Humans , Immunohistochemistry , Male , Neoplasm Transplantation , Prostate/anatomy & histology , Prostate/pathology , Prostatic Neoplasms/metabolism , Prostatic Neoplasms/pathology , Prostatic Neoplasms/physiopathology , Prostatic Neoplasms/radiotherapy , Protons , Rats , Time Factors
17.
Eur J Endocrinol ; 148(5): 551-7, 2003 May.
Article in English | MEDLINE | ID: mdl-12720539

ABSTRACT

OBJECTIVE: Delayed sexual maturation and low body weight is common in cystic fibrosis (CF). Concomitant data on sex hormones and concomitant body composition are lacking in men with CF. DESIGN: Cross-sectional study. SUBJECTS AND METHODS: Serum levels of testosterone, 17beta-oestradiol (E(2)), 25-hydroxyvitamin D (25(OH)D), sex hormone-binding globulin (SHBG) and LH were measured by RIA and total and regional lean body mass (LBM), fat body mass (FBM), bone mineral content and bone mineral density (BMD) were assessed by dual-energy X-ray absorptiometry, in men with CF (n=40; age 24.7+/-5.4 years) and age-matched healthy controls (n=28; age 25.7+/-3.7). Only men without acute disease exacerbation or systemic glucocorticoid treatment were included. RESULTS: Mean levels of hormonal serum parameters differed significantly between healthy controls (testosterone=20.2+/-5.5 nmol/l; E(2)=95.0+/-20.2 pmol/l; 25(OH)D=62.8+/-28.3 nmol/l) and patients (testosterone=15.9+/-4.1 nmol/l; E(2)=60.7+/-19.4 pmol/l; 25(OH)D=39.5+/-17.8 nmol/l; P<0.001) while no difference was found for SHBG or LH. Eleven (for E(2), 19 of 40, for 25(OH)D, 20 of 40) out of 40 patients had serum testosterone levels 2 s.d. below the mean of normal. Men with CF showed a relative shift from FBM to LBM and a different body fat distribution compared with healthy controls (P<0.01). Testosterone was not correlated with weight, total or regional LBM or FBM, but significantly with BMD (r=0.32; P<0.05) independently from body height and 25(OH)D levels. E(2) was correlated with regional and total FBM (r=0.48; P<0.05). In a multiple regression analysis of the joint effect of testosterone and body components on E(2), a testosterone-independent effect was found for FBM. CONCLUSIONS: CF patients with stable disease have moderately reduced serum testosterone levels. This might already imply detrimental effects on bone. The change in LBM of patients appears to have no direct association with sex hormone levels while low FBM might cause reduced net conversion of serum testosterone to E(2) with possible effects on FBM distribution.


Subject(s)
Body Composition , Cystic Fibrosis/metabolism , Gonadal Steroid Hormones/blood , Absorptiometry, Photon , Adult , Bone Density , Cross-Sectional Studies , Cystic Fibrosis/blood , Humans , Male , Testosterone/blood
18.
Rev Med Interne ; 23(12): 973-82, 2002 Dec.
Article in French | MEDLINE | ID: mdl-12504233

ABSTRACT

PURPOSE: Among the locations of venous thrombosis, even if rare, cerebral-vein thrombosis is a severe event with a high mortality rate. No aetiology is found in 20 to 30% of the cases. In recent years, inherited coagulation disorders have been described, as risk factors for venous thrombosis. We report the results of a retrospective study of 27 patients who suffered cerebral-vein thrombosis, in which coagulation abnormalities have been searched for. METHOD: The patients were referred to the haemostasis laboratory of the Henri Mondor hospital between august 1982 and June 1988, after a cerebral-vein thrombosis. The predisposing factors, personal and family history of thromboembolism, clinical presentation, thrombosis location, evolution under treatment and long-term outcome, have been noted. Deficiencies in antithrombine, protein C, protein S, the Factor V Leiden and the G20210A prothrombin-gene mutation, the presence of lupus anticoagulant, of anticardiolipin antibodies as well as a hyperhomocysteinaemia have been searched, either at the initial presentation, or a posteriori. RESULTS: Fourty-one percent of patients had a coagulation abnormality. The prevalence of the different abnormalities was: inherited deficiency in AT 7.4%, in PC 8%, in PS 12.5%, factor V Leiden mutation 12%, G20210A prothrombin-gene mutation 12%. Two patients had combined defects: AT and PC deficiency in one, F V Leiden and F II G20210A mutations in one. e of the patient had lupus anticoagulant. Three patients had a significant rate of anticardiolipin antibodies. Five patients out of eight displayed a moderate hyperhomocysteinaemia. Nothing (past history, age, predisposing factors) distinguished those patients bearing a coagulation disorder from the others. The venous thromboembolic relapse rate of 15 % (4/27 patients). Three of them had an inherited thrombophilic abnormality. CONCLUSION: We recommend an investigation of the haemostasis after every cerebral venous thrombosis.


Subject(s)
Intracranial Thrombosis/etiology , Adult , Aged , Aged, 80 and over , Female , Humans , Infant , Male , Middle Aged , Retrospective Studies
19.
Br J Radiol ; 75(899): 903-8, 2002 Nov.
Article in English | MEDLINE | ID: mdl-12466256

ABSTRACT

Evaluation of tumour size modifications in response to treatment is a critical issue in the management of advanced malignancies. In 1981, the World Health Organization (WHO) established guidelines for tumour response assessment. These WHO1981 criteria were recently simplified in a revised version, named RECIST (Response Evaluation Criteria in Solid Tumours), which uses unidimensional instead of bidimensional measurements, a reduced number of measured lesions, withdrawal of the progression criteria based on isolated increase of a single lesion, and different shrinkage threshold for definitions of tumour response and progression. In order to validate these new guidelines, we have compared results obtained with both classifications in a prospective series of 91 patients receiving chemotherapy for metastatic colorectal cancer. Data from iterative tomographic measurements were fully recorded and reviewed by an expert panel. The overall response and progression rates according to the WHO1981 criteria were 19% and 58%, respectively. Using RECIST criteria, 16 patients were reclassified in a more favourable subgroup, the overall response rate being 28% and the progression rate 45% (non-weighted kappa concordance test 0.72). When isolated increase of a single measurable lesion is not taken into account for progression with the WHO1981 criteria, only 7 patients were reclassified and the kappa test was satisfying, i.e. > or =0.75, for the whole population as well as for each of the responding and progressive subgroups. Since it provides concordant results with a simplified method, the use of RECIST criteria is recommended for evaluation of treatment efficacy in clinical trials and routine practice.


Subject(s)
Adenocarcinoma/drug therapy , Adenocarcinoma/secondary , Antineoplastic Agents/therapeutic use , Colorectal Neoplasms/pathology , Practice Guidelines as Topic , Adenocarcinoma/pathology , Aged , Disease Progression , Female , Health Status Indicators , Humans , Male , Middle Aged , Prospective Studies , Survival Rate , Treatment Outcome
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