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991.
Maria Pia Bondioni Ugo Ernesto Pazzaglia Claudia Izzi Giuseppe Di Gaetano Francesco Laffranchi Maurizia Baldi Federico Prefumo 《La Radiologia medica》2017,122(11):880-891
Objective
The purpose of the paper was to assess the morphometric parameters to improve the specificity of the ultrasound (US) signs for the early differential diagnosis between two lethal dysplasias, as thanatophoric dysplasia (TD) and osteogenesis imperfecta type 2 (OI-2).Method
The diaphyseal length and the bowed shape of long bones associated with vertebral body dimension assessment were investigated in a group of 14 pregnancy terminations carried out in the time period 2007–2013. The definitive diagnosis was established after pregnancy termination by means of skeletal standardized X-rays, histopathology and gene analysis.Results
TD and OI-2 long bones were significantly shorter than controls. No significant differences were observed between the two dysplasias. The bowing angle was higher in OI-2; a true angulation or eventually axial displacement was present only in the latter. Furthermore, they did not show any evidence of vertebral collapse. The thanatophoric dysplasia presented less bowed long bones, and never true angulation. The spine was steadily characterized by flattened anterior vertebral bodies.Conclusion
Long bone shortening is not a sufficient and accurate sign for early sonographic differential diagnosis between TD and OI-2. Angled diaphysis, axial diaphyseal displacement and a conserved vertebral body height in the prenatal period support the diagnosis of osteogenesis imperfecta type 2, while moderately regular bowed diaphysis associated with platyspondyly that of thanatophoric dysplasia.992.
Elisa Zuffa Manuela Mancini Gianluca Brusa Eleonora Pagnotta Claudia Maria Hattinger Massimo Serra 《International journal of radiation biology》2013,89(7):591-601
Purpose: To investigate the impact of TP53 (tumor protein 53, p53) on genomic stability of osteosarcoma (OS).Materials and methods: In first instance, we expressed in OS cell line SAOS-2 (lacking p53) a wild type (wt) p53 construct, whose protein undergoes nuclear import and activation in response to ionizing radiations (IR). Thereafter, we investigated genomic imbalances (amplifications and deletions at genes or DNA regions most frequently altered in human cancers) associated with radio-resistance relative to p53 expression by mean of an array-based comparative genomic hybridization (aCGH) strategy. Finally we investigated a putative marker of radio-induced oxidative stress, a 4,977 bp deletion at mitochondrial (mt) DNA usually referred to as ‘common’ deletion, by mean of a polimerase chain reaction (PCR) strategy.Results: In radio-resistant subclones generated from wt p53-transfected SAOS-2 cells DNA deletions were remarkably reduced and the accumulation of ‘common’ deletion at mtDNA (that may let the persistence of oxidative damage by precluding detoxification from reactive oxygen species [ROS]) completely abrogated.Conclusions: The results of our study confirm that wt p53 has a role in protection of OS cell DNA integrity. Multiple mechanisms involved in p53 safeguard of genomic integrity and prevention of deletion outcome are discussed. 相似文献
993.
Kerstin Römermann Thomas Wanek Marion Bankstahl Jens P. Bankstahl Maren Fedrowitz Markus Müller Wolfgang Löscher Claudia Kuntner Oliver Langer 《Nuclear medicine and biology》2013,40(7):873-878
IntroductionPositron emission tomography (PET) with [11C]verapamil, either in racemic form or in form of the (R)-enantiomer, has been used to measure the functional activity of the adenosine triphosphate-binding cassette (ABC) transporter P-glycoprotein (Pgp) at the blood–brain barrier (BBB). There is some evidence in literature that verapamil inhibits two other ABC transporters expressed at the BBB, i.e. multidrug resistance protein 1 (MRP1) and breast cancer resistance protein (BCRP). However, previous data were obtained with micromolar concentrations of verapamil and do not necessarily reflect the transporter selectivity of verapamil at nanomolar concentrations, which are relevant for PET experiments. The aim of this study was to assess the selectivity of verapamil, in nanomolar concentrations, for Pgp over MRP1 and BCRP.MethodsConcentration equilibrium transport assays were performed with [3H]verapamil (5 nM) in cell lines expressing murine or human Pgp, human MRP1, and murine Bcrp1 or human BCRP. Paired PET scans were performed with (R)-[11C]verapamil in female FVB/N (wild-type), Mrp1(?/?), Mdr1a/b(?/?), Bcrp1(?/?) and Mdr1a/b(?/?)Bcrp1(?/?) mice, before and after Pgp inhibition with 15 mg/kg tariquidar.ResultsIn vitro transport experiments exclusively showed directed transport of [3H]verapamil in Mdr1a- and MDR1-overexpressing cells which could be inhibited by tariquidar (0.5 μM). In PET scans acquired before tariquidar administration, brain-to-blood ratio (Kb,brain) of (R)-[11C]verapamil was low in wild-type (1.3 ± 0.1), Mrp1(?/?) (1.4 ± 0.1) and Bcrp1(?/?) mice (1.8 ± 0.1) and high in Mdr1a/b(?/?) (6.9 ± 0.8) and Mdr1a/b(?/?)Bcrp1(?/?) mice (7.9 ± 0.5). In PET scans after tariquidar administration, Kb,brain was significantly increased in Pgp-expressing mice (wild-type: 5.0 ± 0.3-fold, Mrp1(?/?): 3.2 ± 0.6-fold, Bcrp1(?/?): 4.3 ± 0.1-fold) but not in Pgp knockout mice (Mdr1a/b(?/?) and Mdr1a/b(?/?)Bcrp1(?/?)).ConclusionOur combined in vitro and in vivo data demonstrate that verapamil, in nanomolar concentrations, is selectively transported by Pgp and not by MRP1 and BCRP at the BBB, which supports the use of (R)-[11C]verapamil or racemic [11C]verapamil as PET tracers of cerebral Pgp function. 相似文献
994.
Claudia Fellner Brit Sommer Nicole Siedhoff Richard Pötter 《Strahlentherapie und Onkologie》1998,174(7):345-349
Background
Modern 3-dimensional treatment planning systems on the basis of sectional imaging allow the calculation of volumes for organs of interest. The aim of this study is to investigate systematically the accuracy of calculations of volumes by the use of a phantom for 4 different treatment planning systems.Material and Method
The tests were done with a phantom with 5 cylindrical structures and 6 spherical shaped structures. After performing a CT-scan and reading the data into the planning systems the structures were contoured and the volumes were calculated in order to compare these values with the values calculated by mathematical equations. This was systematically done as a function of different parameters.Results
Comparing different methods of contouring showed notable influence on the result. Parameters as number of calculation points or length of cylinders showed no significant differences. In summary, the mean deviations for cylinders were +7% for system A, ?2% for B, ?17% for C, and 0% for D. For larger spheres (radii between 5 and 2.5 cm) the mean deviations were ?5% for A, +3% for B, +1% for C, and +5% for D. For smaller spheres (radii between 1.75 and 1.25 cm) the mean deviations were ?14% for A, ?2% for B, ?10% for C, and ?4% for D.Conclusion
Verifying results of planning systems is important for the daily routine, but it has to be taken into account, that small changes of the radius of a cylinder or sphere cause substantial volume changes. The differences are also caused by inaccuracies of the whole procedure, e. g., the CT study, the shape and dimensions of the cylinders and the spheres and the CT information and the delineariation of the structures. 相似文献995.
Riccardo Del Vescovo Claudia Lucia Piccolo Nicoletta Della Vecchia Francesco Giurazza Roberto Luigi Cazzato Rosario Francesco Grasso Bruno Beomonte Zobel 《European journal of radiology》2014
Objective
Pelvic floor dysfunctions affect a very high proportion of female population. Magnetic resonance imaging is the only technique able to provide a multiplanar overview of pelvic organs and muscles without the use of ionizing radiation. The aim of our prospective study is to objectively evaluate the effectiveness of perineal re-education applying MR technique.Materials and methods
22 patients affected by stress urinary incontinence were enrolled in our prospective study. They underwent urogynaecological, urodynamic examinations, and a questionnaire about symptoms (ICIQ-UI) to investigate the degree of their interference with daily activities. Then they underwent a morphological and dynamic MR exam.Results
The pre-perineal rehabilitation MR examinations showed an asymmetry of the levator ani muscle in 87% of patients; the remaining 13% showed a muscular bilateral volume reduction. In the group with unilateral defect, the muscle total volume had values between 15 and 21 cm3. Its overall volume was 34.2% smaller on the defective side (9.28 ± 0.26 cm3) compared to the normal side (12.64 ± 12.31 cm3, P < 0.001).In patients with a bilateral impairment, the muscle was replaced by fibro-fatty tissue, without a significant asymmetry between the two sides. The post-perineal rehabilitation MR tests showed three different degrees of response to therapy, with a “complete response” found in 67% of patients and no response in 13%.Conclusions
MR is an useful tool in the management of patients affected by stress urinary incontinence with indication for perineal rehabilitation. Its objective data allow to distinguish different types of response to therapy and, consequently, different outcomes in terms of additional treatments. 相似文献996.
Claudia Brogsitter Klaus Zöphel Holger Hartmann Margret Schottelius Hans-Jürgen Wester Jörg Kotzerke 《European journal of nuclear medicine and molecular imaging》2014,41(6):1158-1165
Purpose
Over recent decades interest in diagnosis and treatment of neuroendocrine tumours (NET) has steadily grown. The basis for diagnosis and therapy of NET with radiolabelled somatostatin (hsst) analogues is the variable overexpression of hsst receptors (hsst1–5 receptors). We hypothesized that radiometal derivatives of DOTA-iodo-Tyr3-octreotide analogues might be excellent candidates for somatostatin receptor imaging. We therefore explored the diagnostic potential of 68Ga-DOTA-iodo-Tyr3-octreotate [68Ga-DOTA,3-iodo-Tyr3,Thr8]octreotide (68Ga-HA-DOTATATE; HA, high-affinity) compared to the established 68Ga-DOTA-Tyr3-octreotate (68Ga-DOTATATE) in vivo.Methods
The study included 23 patients with known somatostatin receptor-positive metastases from NETs, thyroid cancer or glomus tumours who were investigated with both 68Ga-HA-DOTATATE and 68Ga-DOTATATE. A patient-based and a lesion-based comparative analysis was carried out of normal tissue distribution and lesion detectability in a qualitative and a semiquantitative manner.Results
68Ga-HA-DOTATATE and 68Ga-DOTATATE showed comparable uptake in the liver (SUVmean 8.9?±?2.2 vs. 9.3?±?2.5, n.s.), renal cortex (SUVmean 13.3?±?3.9 vs. 14.5?±?3.7, n.s.) and spleen (SUVmean 24.0?±?6.7 vs. 22.9?±?7.3, n.s.). A somewhat higher pituitary uptake was found with 68Ga-HA-DOTATATE (SUVmean 6.3?±?1.8 vs. 5.4?±?2.1, p?<?0.05). On a lesion-by-lesion basis a total of 344 lesions were detected. 68Ga-HA-DOTATATE demonstrated 328 lesions (95.3 % of total lesions seen), and 68Ga-DOTATATE demonstrated 332 lesions (96.4 %). The mean SUVmax of all lesions was not significantly different between 68Ga-HA-DOTATATE and 68Ga-DOTATATE (17.8?±?11.4 vs. 16.7?±?10.7, n.s.).Conclusion
Our analysis demonstrated very good concordance between 68Ga-HA-DOTATATE and 68Ga-DOTATATE PET data. As the availability and use of 68Ga-HA-DOTATATE is not governed by patent restrictions it may be an attractive alternative to other 68Ga-labelled hsst analogues. 相似文献997.
Kamilla Smolarz Bernd Joachim Krause Frank Philipp Graner Franziska Martina Wagner Hans-Jürgen Wester Tina Sell Claudia Bacher-Stier Lüder Fels Ludger Dinkelborg Markus Schwaiger 《European journal of nuclear medicine and molecular imaging》2013,40(12):1861-1868
Purpose
Novel tracers for the diagnosis of malignant disease with PET and PET/CT are being developed as the most commonly used 18F deoxyglucose (FDG) tracer shows certain limitations. Employing radioactively labelled glutamate derivatives for specific imaging of the truncated citrate cycle potentially allows more specific tumour imaging. Radiation dosimetry of the novel tracer BAY 85-8050, a glutamate derivative, was calculated and the effective dose (ED) was compared with that of FDG.Methods
Five healthy volunteers were included in the study. Attenuation-corrected whole-body PET/CT scans were performed from 0 to 90 min, at 120 and at 240 min after injection of 305.0?±?17.6 MBq of BAY 85-8050. Organs with moderate to high uptake at any of the imaging time points were used as source organs. Total activity in each organ at each time point was measured. Time–activity curves (TAC) were determined for the whole body and all source organs. The resulting TACs were fitted to exponential equations and accumulated activities were determined. OLINDA/EXM software was used to calculate individual organ doses and the whole-body ED from the acquired data.Results
Uptake of the tracer was highest in the kidneys due to renal excretion of the tracer, followed by the pancreas, heart wall and osteogenic cells. The mean organ doses were: kidneys 38.4?±?11.2 μSv/MBq, pancreas 23.2?±?3.8 μSv/MBq, heart wall 17.4?±?4.1 μSv/MBq, and osteogenic cells 13.6?±?3.5 μSv/MBq. The calculated ED was 8.9?±?1.5 μSv/MBq.Conclusion
Based on the distribution and dose estimates, the calculated radiation dose of BAY 85-8050 is 2.67?±?0.45 mSv at a patient dose of 300 MBq, which compares favourably with the radiation dose of FDG (5.7 mSv). 相似文献998.
Pediculosis capitis is one of the most frequent infectious diseases in childhood. If not diagnosed and treated rapidly, considerable
clinical pathology may develop. The ubiquitous parasitic skin disease is characterized by a lack of sound epidemiological
data, and factors which influence disease occurrence are still enigmatic. To investigate whether, in Germany, head lice infestation
follows a seasonal pattern, we analyzed the weekly head lice consultations at the Health Department of Braunschweig City,
Lower Saxony, for a period of 5 years, and compared the data with the units of pediculocides sold by two wholesalers to German
pharmacies during a period of 2 and 3 years, respectively. The number of consultations did not show a clear seasonality, although
there was a tendency of fewer consultations during school holidays, and an increase when schools opened again after Christmas,
Easter, summer, and autumn holidays. In contrast, the number of packages of pediculocides sold followed a distinct seasonal
rhythm with a maximum between calendar week 34 and 40, i.e., from mid September to end of October. In Germany, occurrence
of pediculosis capitis varies according to the season of the year with a maximum in late summer and early autumn. 相似文献
999.
Christin Wolfram Claudia Rasche Heike Audring Michael Wahls Margitta Worm 《European archives of oto-rhino-laryngology》2009,266(5):677-683
Cellular inflammation of the nasal mucosa demonstrates a local immune response which plays an important role in allergic rhinitis.
The aim of the present study was to characterize nasal mucosal lymphocytes regarding their activation and differentiation
state by direct ex vivo flowcytometric analysis. Lymphocytes from the inferior turbinates were isolated by a mechanical method
of preparation and, for comparison, from peripheral blood by Ficoll gradient centrifugation. Patients suffering from rhinitis
or difficulty in nasal breathing were divided into an allergic (pollen-allergy, n = 13) and non-allergic group (n = 24). Expression of different T- and B-cell markers was determined by flowcytometric analysis. CD4+ T-cells from the nasal
mucosa exhibited a memory phenotype (CD45RO+, 97%), were highly activated (CD69+, 43–73%), and showed low expression of the
cutaneous lymphocyte antigen (CLA+, 5%). Nasal CD20+ B-lymphocytes expressed significantly higher levels of mIgE and lower
levels of CD23 and CD80 than peripheral B-cells. Subsets of CD80+ (4%) and CD86+ (6%) CD20+ B-lymphocytes were identified
in the nasal mucosa. No significant differences between allergic and non-allergic individuals were determined. As expected,
the data show profound phenotypical differences between circulating peripheral blood and nasal mucosal lymphocytes. Activated
memory lymphocytes are present in the nasal mucosa from allergic, but also non-allergic patients and may indicate to a significant
role of a local inflammatory state without systemic criteria for allergy. In our study, we show that direct ex vivo isolation
of lymphocytes is practicable method and offers a new technique to examine the local nasal allergic immune response using
a multiparametric phenotypical analysis.
Christin Wolfram and Claudia Rasche contributed equally to this work. 相似文献
1000.
Simona Eva Zitnik Franz Rüschendorf Sebastian Müller Claudia Sengler Young‐Ae Lee Rupino W. Griffioen Paolo Meglio Ulrich Wahn Heiko Witt Renate Nickel 《Pediatric allergy and immunology》2009,20(6):551-555
Increased total and specific serum immunoglobulin E (IgE) levels are common characteristics of atopic diseases and their basal production is proposed to be under strong genetic control. Interleukin 13 (IL13) variants have been consistently associated with total serum IgE levels in white populations with a strongest association in non‐atopics. The aim of this study was to test the IL13 p.R130Q and c.1‐1111C>T variants in children with atopic dermatitis (AD) for associations with total serum IgE and early sensitization to common food and inhalant allergens and with asthma. We included 453 children with AD [participants of the Early Treatment of the Atopic Child (ETAC) study] that were followed from the age of 12–24 months for 3 yr. Total and specific IgE were determined at four time points. We genotyped the IL13 p.R130Q and c.1‐1111C>T variants by melting curve analysis. In children up to 4 yr of age, the 130Q allele was related to slightly higher total IgE levels compared to heterozygotes and 130R homozygotes. More importantly, both IL13 variants were significantly associated with sensitization to food allergens, with most significant results for sensitization to egg (p = 0.0001). Although early sensitization to hen’s egg represents a strong risk factor for subsequent sensitization to inhalant allergens and asthma, the investigated IL13 variants were not associated with these phenotypes at the age of 48–60 months. In summary IL13 variants contribute to elevated levels of total serum IgE in young atopic children and are strongly associated with sensitization to food allergens, particularly to hen’s egg. These findings suggest that IL13 variants play a major role not only in non‐cognate but also in allergen specific IgE synthesis. 相似文献