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1.
Mol Biol Rep ; 51(1): 568, 2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38656400

ABSTRACT

BACKGROUND: Tumor embolism is a very rare primary manifestation of cancers and the diagnosis is challenging, especially if located in the pulmonary arteries, where it can mimic nonmalignant pulmonary embolism. Intimal sarcoma is one of the least commonly reported primary tumors of vessels with only a few cases reported worldwide. A typical location of this malignancy is the pulmonary artery. Herein, we present a case report of an intimal sarcoma with primary manifestation in the pulmonary arteries. A 53-year-old male initially presented with dyspnea. On imaging, a pulmonary artery embolism was detected and was followed by thrombectomy of the right ventricular outflow tract, main pulmonary artery trunk, and right pulmonary artery after ineffective lysis therapy. Complementary imaging of the chest and abdomen including a PET-CT scan demonstrated no evidence of a primary tumor. Subsequent pathology assessment suggested an intimal sarcoma further confirmed by DNA methylation based molecular analysis. We initiated adjuvant chemotherapy with doxorubicin. Four months after the completion of adjuvant therapy a follow-up scan revealed a local recurrence without distant metastases. DISCUSSION: Primary pulmonary artery intimal sarcoma (PAS) is an exceedingly rare entity and pathological diagnosis remains challenging. Therefore, the detection of entity-specific molecular alterations is a supporting argument in the diagnostic spectrum. Complete surgical resection is the prognostically most important treatment for intimal cardiac sarcomas. Despite adjuvant chemotherapy, the prognosis of cardiac sarcomas remains very poor. This case of a PAS highlights the difficulty in establishing a diagnosis and the aggressive natural course of the disease. CONCLUSION: In case of atypical presentation of a pulmonary embolism, a tumor originating from the great vessels should be considered. Molecular pathology techniques support in establishing a reliable diagnosis.


Subject(s)
Pulmonary Artery , Sarcoma , Thrombosis , Humans , Male , Middle Aged , Pulmonary Artery/pathology , Sarcoma/diagnosis , Sarcoma/pathology , Tunica Intima/pathology , Vascular Neoplasms/diagnosis , Vascular Neoplasms/pathology , Pulmonary Embolism/diagnosis , Diagnosis, Differential
2.
Phys Rev Lett ; 132(10): 106901, 2024 Mar 08.
Article in English | MEDLINE | ID: mdl-38518321

ABSTRACT

A multiple pump-terahertz probe experiment enables the clear distinction between elastic and inelastic scattering of excitons with a free electron-hole plasma in (Ga,In)As multiquantum wells. Low plasma energies dictate the prevalence of elastic scattering by inhibiting inelastic processes due to the absence of final states for quasiparticles. Yet, an increased plasma energy results in a progressive destruction of excitons. Notably, despite plasma energy variations, the interaction strength between excitons and the electron-hole plasma remains unaltered.

3.
J Cancer Res Clin Oncol ; 148(2): 387-400, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34705105

ABSTRACT

BACKGROUND: We explored the hypothesis that high-quality standards in diagnostic mammography can lead to an early diagnosis of breast cancers and identifies at risk populations outside screening programs. The histopathological features and distribution of the TNM classification were examined in relation to patient age in a large group of women with breast cancers participating in the Quality Assured Mamma Diagnostic (QuaMaDi) program of the state of Schleswig-Holstein. PATIENTS AND METHODS: Surgical pathological reports were studied for clinicopathological characteristics, receptor status, molecular subtype and tumor stage. The analysis was conducted by dividing the study population into three age groups: women under 50 years (pre-screening), 50-69 years (peri-screening) and over 70 years (post-screening). RESULTS: 7.111 biopsies and 2.887 resection specimens were included. Breast cancer was diagnosed in 4.241 (59.7%) cases, one fourth of them in women < 50 years. Elderly women (> 70 years) had more well-differentiated, estrogen receptor (ER)-positive and HER2-negative carcinomas, whereas younger women (< 50 years) tended to have more poorly differentiated, ER negative, and HER2-positive carcinomas. 47% of breast carcinoma were luminal B tumors and were most common regardless of age. 70.4% of resected specimen had pT1 stage. Nodal negative were 71.2%. CONCLUSION: In QuaMaDi breast cancer was diagnosed at an early and potentially curable stage of the disease due to high-quality standards in diagnostic mammography. In addition, regardless of age, an increased number of prognostically unfavorable molecular subtypes were detected. Thus, QuaMaDi helps to identify at risk populations. QuaMaDi significantly improves diagnostic mammography and complements mammography screening programs.


Subject(s)
Breast Neoplasms/diagnosis , Breast Neoplasms/epidemiology , Carcinoma/diagnosis , Carcinoma/epidemiology , Adult , Age Factors , Aged , Aged, 80 and over , Breast Neoplasms/pathology , Carcinoma/pathology , Early Detection of Cancer/methods , Early Detection of Cancer/standards , Female , Germany/epidemiology , Humans , Mammography/standards , Mammography/statistics & numerical data , Mass Screening/organization & administration , Mass Screening/standards , Middle Aged , Neoplasm Staging , Quality Assurance, Health Care/organization & administration , Quality Assurance, Health Care/standards , Registries
4.
Trauma Case Rep ; 32: 100432, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33665323

ABSTRACT

INTRODUCTION: False traumatic aneurysm (FTA) or pseudoaneurysm and traumatic arteriovenous fistulas (TAVF) are rare pathologies in civilian trauma and mainly result from stabs or gunshot wounds. The posterior tibial artery as site of trauma is very rare. PRESENTATION OF CASE: We report on a 39-year old female patient who was suffering from combined FTA and TAVF of the posterior tibial artery after falling into a wine glass. CT-imaging as well as duplex ultrasound and selective arteriography were performed, and two stent-grafts were inserted. DISCUSSION: Based on the presented case, incidence of the described pathology, treatment options and outcomes are discussed. CONCLUSION: Adequate imaging in penetrating wounds to the extremities is crucial in order to provide diagnosis and treatment of concomitant lesions.

5.
Ultraschall Med ; 36(6): 550-62; quiz 563-5, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26274379

ABSTRACT

Ultrasound elastography is an established method for characterization of focal lesions in the breast. Different techniques and analyses of the images may be used for the characterization. This article addresses the use of ultrasound elastography in breast cancer diagnosis. In the first part of the article the techniques behind both strain- and shear-wave-elastography are explained and followed by a section on how to obtain adequate elastography images and measurements. In the second part of the article the application of elastography as an adjunct to B-mode ultrasound in clinical practice is described, and the potential diagnostic gains and limitations of elastography are discussed.


Subject(s)
Breast Neoplasms/diagnostic imaging , Elasticity Imaging Techniques/methods , Ultrasonography, Mammary/methods , Female , Humans , Multimodal Imaging , Sensitivity and Specificity
6.
Article in English | MEDLINE | ID: mdl-24730915

ABSTRACT

Scattering experiments with microwave cavities were performed and the effects of broken time-reversal invariance (TRI), induced by means of a magnetized ferrite placed inside the cavity, on an isolated doublet of nearly degenerate resonances were investigated. All elements of the effective Hamiltonian of this two-level system were extracted. As a function of two experimental parameters, the doublet and the associated eigenvectors could be tuned to coalesce at a so-called exceptional point (EP). The behavior of the eigenvalues and eigenvectors when encircling the EP in parameter space was studied, including the geometric amplitude that builds up in the case of broken TRI. A one-dimensional subspace of parameters was found where the differences of the eigenvalues are either real or purely imaginary. There, the Hamiltonians were found to be PT invariant under the combined operation of parity (P) and time reversal (T) in a generalized sense. The EP is the point of transition between both regions. There a spontaneous breaking of PT occurs.

7.
Nat Commun ; 5: 3194, 2014.
Article in English | MEDLINE | ID: mdl-24476716

ABSTRACT

It is generally impossible to probe a quantum system without disturbing it. However, it is possible to exploit the back action of quantum measurements and strong couplings to tailor and protect the coherent evolution of a quantum system. This is a profound and counterintuitive phenomenon known as quantum Zeno dynamics. Here we demonstrate quantum Zeno dynamics with a rubidium Bose-Einstein condensate in a five-level Hilbert space. We harness measurements and strong couplings to dynamically disconnect different groups of quantum states and constrain the atoms to coherently evolve inside a two-level subregion. In parallel to the foundational importance due to the realization of a dynamical superselection rule and the theory of quantum measurements, this is an important step forward in protecting and controlling quantum dynamics and, broadly speaking, quantum information processing.

8.
Phys Rev Lett ; 111(3): 030403, 2013 Jul 19.
Article in English | MEDLINE | ID: mdl-23909297

ABSTRACT

Scattering is an important phenomenon which is observed in systems ranging from the micro- to macroscale. In the context of nuclear reaction theory, the Heidelberg approach was proposed and later demonstrated to be applicable to many chaotic scattering systems. To model the universal properties, stochasticity is introduced to the scattering matrix on the level of the Hamiltonian by using random matrices. A long-standing problem was the computation of the distribution of the off-diagonal scattering-matrix elements. We report here an exact solution to this problem and present analytical results for systems with preserved and with violated time-reversal invariance. Our derivation is based on a new variant of the supersymmetry method. We also validate our results with scattering data obtained from experiments with microwave billiards.

9.
Community Dent Health ; 30(2): 88-93, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23888538

ABSTRACT

UNLABELLED: Advances in digital communication, such as the internet, now provide a cost effective channel to reach and help families struggling to establish good oral hygiene in their homes. This paper describes a novel internet based oral hygiene intervention whose design draws from advances in social cognitive models of behaviour change. Intervention components included role-modelling cartoons for children, a guide for parents on using rewards, a personalised plan with clear steps, tips to follow and a weekly 10-minute review of progress. OBJECTIVE: To evaluate the efficacy of the online coaching programme; specifically we expected that those in the intervention group would brush their teeth more frequently during the intervention period than those in the control group. BASIC RESEARCH DESIGN: An exploratory trial using a randomised controlled parallel approach. PARTICIPANTS: Children aged 5 to 9 years from 44 families (23 control and 21 intervention). MAIN OUTCOME MEASURE: An objective monitoring of tooth brushing. RESULTS: In the 3-week intervention period, children from families assigned to the coaching programme brushed their teeth 38% more often than those in the control group. CONCLUSIONS: The programme was effective in a number of respects. Opportunities for further research are discussed, including the need to create a more engaging system and so increase compliance.


Subject(s)
Internet , Oral Hygiene/education , Parents , Teaching/methods , Toothbrushing/statistics & numerical data , Cartoons as Topic , Cell Phone , Child , Child Behavior , Child, Preschool , Electronic Mail , Female , Health Behavior , Humans , Male , Motivation , Parent-Child Relations , Pilot Projects , Reward , Teaching Materials , Text Messaging , Toothbrushing/instrumentation
11.
Ultraschall Med ; 34(3): 254-9, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23709241

ABSTRACT

PURPOSE: To determine the benefit of ShearWave™ Elastography (SWE™) in the ultrasound characterization of BI-RADS® 3 breast lesions in a diagnostic population. MATERIALS AND METHODS: 303 BI-RADS® 3 lesions (mean size: 13.2 mm, SD: 7.5 mm) from the multicenter BE1 prospective study population were analyzed: 201 (66%) had cytology or core biopsy, and the remaining 102 had a minimum follow-up of one year; 8 (2.6%) were malignant. 7 SWE features were evaluated with regard to their ability to downgrade benign BI-RADS® 3 masses. The performance of each SWE feature was assessed by evaluating the number of lesions correctly reclassified and the impact on cancer rates within the new BI-RADS® 3' lesion group. RESULTS: No malignancies were found with an E-color "black to dark blue", which allowed the downgrading of 110/303 benign masses (p < 0.0001), with a non-significant increase in BI-RADS® 3' malignancy rate from 2.6% to 4.1%. E-max ≤ 20 kPa (2.6 m/s) was able to downgrade 48/303 (p < 0.0001) lesions with a lower increase in BI-RADS® 3' malignancy rate (3.1%). No other SWE features were useful for reclassifying benign BI-RADS® 3 lesions. CONCLUSION: Applying simple reclassification rules, SWE assessment of the maximum stiffness of lesions allowed the downgrading of a sub-group of benign BI-RADS® 3 lesions. This was accompanied by a non-significant increase in the malignancy rate in the new BI-RADS® 3 class.


Subject(s)
Breast Neoplasms/diagnostic imaging , Breast Neoplasms/pathology , Elasticity Imaging Techniques/instrumentation , Elasticity Imaging Techniques/methods , Image Enhancement/methods , Image Interpretation, Computer-Assisted/methods , Ultrasonography, Mammary/instrumentation , Ultrasonography, Mammary/methods , Adult , Aged , Aged, 80 and over , Breast Neoplasms/classification , Equipment Design , Female , Humans , Middle Aged , Neoplasm Grading , Neoplasm Staging , Risk , Sensitivity and Specificity , Young Adult
13.
Bioinform Biol Insights ; 6: 287-302, 2012.
Article in English | MEDLINE | ID: mdl-23236254

ABSTRACT

BACKGROUND: In the face of growing resistance in malaria parasites to drugs, pharmacological combination therapies are important. There is accumulating evidence that methylene blue (MB) is an effective drug against malaria. Here we explore the biological effects of both MB alone and in combination therapy using modeling and experimental data. RESULTS: We built a model of the central metabolic pathways in P. falciparum. Metabolic flux modes and their changes under MB were calculated by integrating experimental data (RT-PCR data on mRNAs for redox enzymes) as constraints and results from the YANA software package for metabolic pathway calculations. Several different lines of MB attack on Plasmodium redox defense were identified by analysis of the network effects. Next, chloroquine resistance based on pfmdr/and pfcrt transporters, as well as pyrimethamine/sulfadoxine resistance (by mutations in DHF/DHPS), were modeled in silico. Further modeling shows that MB has a favorable synergism on antimalarial network effects with these commonly used antimalarial drugs. CONCLUSIONS: Theoretical and experimental results support that methylene blue should, because of its resistance-breaking potential, be further tested as a key component in drug combination therapy efforts in holoendemic areas.

14.
Neuroscience ; 227: 313-26, 2012 Dec 27.
Article in English | MEDLINE | ID: mdl-23069763

ABSTRACT

The endocannabinoid system is crucially involved in the regulation of brain activity and inflammation. We have investigated the localization of cannabinoid CB1 and CB2 receptors in adult rat brains before and after focal cerebral ischemia due to endothelin-induced transient occlusion of the middle cerebral artery (eMCAO). Using immunohistochemistry, both receptor subtypes were identified in cortical neurons. After eMCAO, neuronal cell death was accompanied by reduced neuronal CB1 and CB2 receptor-linked immunofluorescence. In parallel, CB1 receptor was found in activated microglia/macrophages 3 days post eMCAO and in astroglia cells at days 3 and 7. CB2 receptor labeling was identified in activated microglia/macrophages or astroglia 3 and 7d ays post ischemia, respectively. In addition, immune competent CD45-positive cells were characterized by pronounced CB2 receptor staining 3 and 7 days post eMCAO. KN38-72717, a potent and selective CB1 and CB2 receptor agonist, revealed a significant, dose-dependent and long-lasting reduction of cortical lesion sizes due to eMCAO, when applied consecutively before, during and after eMCAO. In addition, severe motor deficits of animals suffering from eMCAO were significantly improved by KN38-7271. KN38-7271 remained effective, even if its application was delayed up to 6h post eMCAO. Finally, we show that the endocannabinoid system assembles a comprehensive machinery to defend the brain against the devastating consequences of cerebral ischemia. In summary, this study underlines the therapeutic potential of CB1 and/or CB2 receptor agonists against neurodegenerative diseases or injuries involving acute or chronic imbalances of cerebral blood flow and energy consumption.


Subject(s)
Brain/metabolism , Movement Disorders/drug therapy , Movement Disorders/pathology , Neuroprotective Agents/therapeutic use , Receptor, Cannabinoid, CB1/metabolism , Receptor, Cannabinoid, CB2/metabolism , Animals , Arachidonic Acids/pharmacology , Brain/drug effects , Brain Infarction/etiology , Brain Infarction/prevention & control , Cannabinoids/therapeutic use , Disease Models, Animal , Dose-Response Relationship, Drug , Ectodysplasins/metabolism , Endocannabinoids/pharmacology , Gene Expression Regulation/drug effects , Glial Fibrillary Acidic Protein/metabolism , Indans/therapeutic use , Infarction, Middle Cerebral Artery/complications , Leukocyte Common Antigens/metabolism , Male , Movement Disorders/etiology , Polyunsaturated Alkamides/pharmacology , Psychomotor Performance/drug effects , Quinoxalines/pharmacology , Quinoxalines/therapeutic use , Rats , Rats, Sprague-Dawley , Sulfonic Acids/therapeutic use , Time Factors
15.
Methods Mol Biol ; 914: 17-24, 2012.
Article in English | MEDLINE | ID: mdl-22976020

ABSTRACT

The presented method to crystallize membrane proteins combines the advantages of the meso-phase crystallization method and the classical vapor diffusion crystallization. It allows fast screening of crystallization conditions employing automated liquid handlers suited for the 96-well crystallization format.


Subject(s)
Crystallization/methods , Membrane Proteins/chemistry , Diffusion , Glycerides/chemistry , Phase Transition , Rhodopsin/chemistry , Temperature , Volatilization , Water/chemistry
16.
Phys Rev Lett ; 108(2): 024101, 2012 Jan 13.
Article in English | MEDLINE | ID: mdl-22324686

ABSTRACT

We demonstrate the presence of parity-time (PT) symmetry for the non-Hermitian two-state Hamiltonian of a dissipative microwave billiard in the vicinity of an exceptional point (EP). The shape of the billiard depends on two parameters. The Hamiltonian is determined from the measured resonance spectrum on a fine grid in the parameter plane. After applying a purely imaginary diagonal shift to the Hamiltonian, its eigenvalues are either real or complex conjugate on a curve, which passes through the EP. An appropriate basis choice reveals its PT symmetry. Spontaneous symmetry breaking occurs at the EP.

17.
Geburtshilfe Frauenheilkd ; 72(5): 412-418, 2012 May.
Article in English | MEDLINE | ID: mdl-25298546

ABSTRACT

Hamartomas can occur in different areas of the breast, but they are rarely found in the breast. Myoid hamartomas with smooth muscle cells of the type described here are particularly unusual. The pathogenesis of this benign entity with its tendency to growth and recurrence is not clear. Excision is the therapy of choice. Capillary hemangiomas are rare vascular malformations of the breast which, in contrast to cavernous hemangiomas, usually remain clinically occult. It is important to differentiate these benign findings from malignant angiosarcoma. The possible heterogeneities between myoid hamartoma and capillary hemangioma using current breast imaging methods for the differential diagnosis (high-resolution ultrasound, duplex sonography, shear wave elastography, digital mammography, minimally invasive intervention) are discussed together with an overview of the literature.

18.
Phys Rev E Stat Nonlin Soft Matter Phys ; 84(1 Pt 2): 016221, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21867287

ABSTRACT

Single and double-slit experiments are performed with two microwave billiards with the shapes of a rectangle and a quarter stadium, respectively. The classical dynamics of the former is regular, whereas that of the latter is chaotic. Microwaves can leave the billiards via slits in the boundary, forming interference patterns on a screen. The aim is to determine the effect of the billiard dynamics on their structure. For this the development of a method for the construction of a directed wave packet by means of an array of multiple antennas was crucial. The interference patterns show a sensitive dependence not only on the billiard dynamics but also on the initial position and direction of the wave packet.

19.
Phys Rev Lett ; 106(15): 150403, 2011 Apr 15.
Article in English | MEDLINE | ID: mdl-21568534

ABSTRACT

We report on the experimental study of an exceptional point (EP) in a dissipative microwave billiard with induced time-reversal invariance (T) violation. The associated two-state Hamiltonian is non-Hermitian and nonsymmetric. It is determined experimentally on a narrow grid in a parameter plane around the EP. At the EP the size of T violation is given by the relative phase of the eigenvector components. The eigenvectors are adiabatically transported around the EP, whereupon they gather geometric phases and in addition geometric amplitudes different from unity.

20.
Opt Lett ; 35(18): 3105-7, 2010 Sep 15.
Article in English | MEDLINE | ID: mdl-20847793

ABSTRACT

An optical resonator, designed for frequency doubling of cw single-frequency radiation, is simultaneously injected by two phase-coherent laser beams with the same frequency. By using standard methods in laser-cavity stabilization, we are able to stabilize the cavity length on resonance with the laser, as well as the relative phase of the fundamental beams, to fulfill the optimum coupling conditions simultaneously on the two input couplers. By using this method, we generate reliably more than 220 mW of single-frequency radiation at 399 nm using two 0.5 W semiconductor tapered amplifiers at 798 nm. This method can be generalized to a larger number of input couplers and holds promise for improving the performances of extreme-UV frequency combs.

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