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1.
Nat Commun ; 15(1): 3798, 2024 May 07.
Article in English | MEDLINE | ID: mdl-38714689

ABSTRACT

Transparent roofs and walls offer a compelling solution for harnessing natural light. However, traditional glass roofs and walls face challenges such as glare, privacy concerns, and overheating issues. In this study, we present a polymer-based micro-photonic multi-functional metamaterial. The metamaterial diffuses 73% of incident sunlight, creating a more comfortable and private indoor environment. The visible spectral transmittance of the metamaterial (95%) surpasses that of traditional glass (91%). Furthermore, the metamaterial is estimated to enhance photosynthesis efficiency by ~9% compared to glass roofs. With a high emissivity (~0.98) close to that of a mid-infrared black body, the metamaterial is estimated to have a cooling capacity of ~97 W/m2 at ambient temperature. The metamaterial was about 6 °C cooler than the ambient temperature in humid Karlsruhe. The metamaterial exhibits superhydrophobic performance with a contact angle of 152°, significantly higher than that of glass (26°), thus potentially having excellent self-cleaning properties.

2.
Breast Care (Basel) ; 17(5): 508-513, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36684406

ABSTRACT

Introduction: Noninterventional study (NIS) on application and effectiveness of primary G-CSF prophylaxis with lipegfilgrastim in primary breast cancer patients undergoing dose-dense (dd) or intense-dose-dense (idd) chemotherapy (CTx) regimen in daily clinical practice. Methods: Prospective, multicenter, single-arm, NIS in 41 private practices and 27 hospitals in Germany. Results: Data analysis of 282 patients with a mean age of 49 years (93.6% of patients <65 years) was performed. Hormone receptor status was triple negative in 29.8% of patients, and 81.9% of patients were HER2 negative. A total of 73.8% of patients received "EC dd → taxane CTx." Patients received lipegfilgrastim prophylaxis in 97.5% of 1,121 documented dd/idd cycles. Overall, the study registered 275 events of SN (CTCAE grade 3 or 4) and 9 events of FN. During the first dd cycle, SN occurred in 33.3% and FN in 1.1% of patients. CTx delay or dose reduction due to neutropenia was required in 2.5% of patients during the 4 dd cycles with lipegfilgrastim support. Overall, 314 adverse events (AEs) were reported from 107 patients and 27 serious AEs from 21 patients. None of the SAEs was "fatal," and CTCAE grade was mostly (89.6%) assessed as "1" or "2." According to the treating physicians, 99.3% of all patients benefitted from lipegfilgrastim prophylaxis, and tolerability was mostly rated "very good" or "good." Conclusion: These results suggest that primary lipegfilgrastim prophylaxis is effective and safe in clinical routine and is beneficial in primary breast cancer patients undergoing dd/idd-ETC CTx.

3.
Cancer ; 120(14): 2199-206, 2014 Jul 15.
Article in English | MEDLINE | ID: mdl-24752999

ABSTRACT

BACKGROUND: The authors investigated whether cancer patients who have comorbid mental health disorders (MD) are at greater risk of early retirement compared with those who do not have MD. METHODS: Individuals ages 18 to 55 years from a consecutive sample of patients who were admitted for inpatient oncologic treatment were interviewed using structured clinical interviews to ascertain MD. The patients were followed for 15 months, and the date of early retirement was documented. Rates of early retirement per 100 person-years (py) in patients with and without MD were compared using multivariate Poisson regression models. RESULTS: At baseline, 491 patients were interviewed, and 150 of those patients (30.6%) were diagnosed with MD. Forty-one patients began full early retirement during follow-up. In patients with MD, the incidence of early retirement was 9.3 per 100 py compared with 6.1 per 100 py in mentally healthy patients. The crude rate ratio (RR) was 1.5 (95% confidence interval [CI], 0.8-2.8). The effect of MD on early retirement was modified in part by income: in patients with low income, the adjusted RR was 11.7, whereas no effect was observed in higher income groups. Patients with depression were at greater risk of retirement when they had higher income (RR, 3.4; P = .05). The effects of anxiety (RR, 2.4; P = .05), adjustment disorders (RR, 1.7; P = .21), and alcohol dependence (RR, 1.8; P = .40) on early retirement were equal across income groups. CONCLUSIONS: Mental health conditions are risk factors for early retirement in cancer patients, although this effect differs according to the type of disorder and the patient's income level.


Subject(s)
Mental Disorders/epidemiology , Neoplasms/epidemiology , Retirement/statistics & numerical data , Adult , Alcoholism/epidemiology , Anxiety/epidemiology , Comorbidity , Depression/epidemiology , Female , Germany/epidemiology , Humans , Interviews as Topic , Male , Middle Aged , Odds Ratio , Poisson Distribution , Prospective Studies
4.
Breast Care (Basel) ; 8(3): 221-9, 2013 Jun.
Article in English | MEDLINE | ID: mdl-24415975

ABSTRACT

The International Consensus Conference on the treatment of primary breast cancer takes place every two years in St. Gallen, Switzerland. The panel in St. Gallen is composed of international experts from different countries. From a German perspective, it seems reasonable to interpret the voting results in the light of AGO-recommendations and S3-guidelines for everyday practice in Germany. Consequently, a team of eight breast cancer experts, of whom two are members of the international St. Gallen panel, commented on the voting results of the St. Gallen Consensus Conference (2013). The main topics at this year's St. Gallen conference were surgical issues of the breast and axilla, radio-therapeutic and systemic treatment options, and the clinical relevance of tumour biology. The clinical utility of multigene assays for supporting individual treatment decisions was also intensively discussed.

5.
BMC Cancer ; 12: 578, 2012 Dec 05.
Article in English | MEDLINE | ID: mdl-23217093

ABSTRACT

BACKGROUND: There is a lack of psychotherapeutic trials of treatments of comorbid depression in cancer patients. Our study determines the efficacy of a manualized short-term psychodynamic psychotherapy and predictors of outcome by personality and quality of the therapeutic relationship. METHODS/DESIGN: Eligible breast cancer patients with comorbid depression are assigned to short-term psychodynamic psychotherapy (up to 20 + 5 sessions) or to treatment as usual (augmented by recommendation for counseling center and physician information). We plan to recruit a total of 180 patients (90 per arm) in two centers. Assessments are conducted pretreatment, after 6 (treatment termination) and 12 months (follow-up). The primary outcome measures are reduction of the depression score in the Hospital Anxiety and Depression Scale and remission of depression as assessed by means of the Structured Clinical Interview for DSM IV Disorders by independent, blinded assessors at treatment termination. Secondary outcomes refer to quality of life. DISCUSSION: We investigate the efficacy of short-term psychodynamic psychotherapy in acute care and we aim to identify predictors for acceptance and success of treatment. TRIAL REGISTRATION: ISRCTN96793588.


Subject(s)
Breast Neoplasms/psychology , Breast Neoplasms/therapy , Depression/etiology , Depression/therapy , Psychotherapy, Brief/methods , Adolescent , Adult , Aged , Comorbidity , Female , Follow-Up Studies , Humans , Middle Aged , Prospective Studies , Quality of Life , Young Adult
6.
Work ; 41 Suppl 1: 252-7, 2012.
Article in English | MEDLINE | ID: mdl-22316731

ABSTRACT

At present, the number of the vehicle requirements has been continuously increasing. These requirements can be related to the customer as well as the technical requirements. Among these, the "feeling of space" of the occupants inside the vehicles can be regarded as one of the most important factors. In this respect, the driver and passengers should be able to experience positive feeling of space inside the vehicle. There are numerous factors that can influence the sense of space inside the vehicle. These include geometry (vehicle dimensions), light exposure, ambient lights, colors, material selection and material surface. Depending on the selection, the sense of space can be dramatically influenced by these factors. In general, human feeling is subjective and cannot be measured by any instrument. The measure can nevertheless be carried out by utilizing the method of subjective evaluation. Throughout the experiments, the method of evaluation is developed and the factors which can influence the interior feeling are analyzed. In this process, psychological perception, architectural aspects and anthropometry are considered and knowledge from the other domains is transferred in the form of a multidisciplinary approach. The experiments with an aim to evaluate the overall sense of space in the vehicle are carried out based on the physical mock up of BMW 1 series (E87). The space perception with different interior dimensions and anthropometric data of test persons are also analyzed. The use of Computer Aided Technology was shown by CATIA V5, PCMAN and RAMSIS. The results show a good correlation between the subjective evaluation and the geometric values.


Subject(s)
Anthropometry , Automobiles , Interior Design and Furnishings , Space Perception , Adolescent , Adult , Consumer Behavior , Female , Germany , Humans , Male , Middle Aged , Surveys and Questionnaires , Young Adult
7.
Gynecol Oncol ; 116(1): 82-7, 2010 Jan.
Article in English | MEDLINE | ID: mdl-19836828

ABSTRACT

OBJECTIVE: The aim of this study was to evaluate patients' acceptance and the reliability and validity of a recently developed instrument to assess quality of life among cervical cancer patients, the European Organization for Research and Treatment of Cancer Cervical Cancer Module (EORTC QLQ-CX24), in surgically treated patients after primary surgery. METHODS: The EORTC QLQ-CX24 was administered to 134 cervical cancer patients who had undergone pelvic surgery. Additional questionnaires completed were the EORTC QLQ-C30, and the Hospital Anxiety and Depression Scale. Sociodemographic and medical data were recorded. RESULTS: Missing values occurred in 4.5% of all non-optional items. Internal consistencies (Cronbach's alpha coefficients) for the three multi-item scales ranged from 0.70 to 0.87 (Symptom Experience 0.70, Body Image 0.87, Sexual/Vaginal Functioning 0.76), whereas scaling errors occurred in 6.8%, 0.0%, and 6.3% of the cases. In all domains, the entire range of the scale was used by patients. The scales were able to discriminate between different subgroups of patients. CONCLUSION: These psychometric analyses confirm that the EORTC QLQ-CX24 is a useful tool for the assessment of quality of life in cervical cancer patients after surgery.


Subject(s)
Psychometrics/methods , Uterine Cervical Neoplasms/psychology , Uterine Cervical Neoplasms/surgery , Adult , Aged , Aged, 80 and over , Female , Humans , Middle Aged , Patient Acceptance of Health Care , Patient Satisfaction , Quality of Life , Reproducibility of Results , Surveys and Questionnaires
8.
J Cell Biochem ; 106(4): 729-37, 2009 Mar 01.
Article in English | MEDLINE | ID: mdl-19173302

ABSTRACT

Hyperplasia and hypertrophy of fat cells can be found in obesity and increased adiposity is associated with endothelial dysfunction as an early event of atherosclerosis. However, it is unclear whether human adipocytes directly influence endothelial protein secretion. To study the crosstalk between fat and endothelial cells, human umbilical venous endothelial cells (HUVECs) were cultured in infranatants (Adipo) of primary differentiated human adipocytes. Interestingly, significantly increased secretion of 23 cytokines and chemokines from HUVECs was detected in four independent experiments after Adipo stimulation by protein array analysis detecting a total of 174 different proteins. Among those, time-dependent Adipo-induced upregulation of cytokine secretion in HUVECs was confirmed by ELISA for interleukin (IL)-8, monokine induced by gamma interferon, macrophage inflammatory protein (MIP)-1beta, MIP-3alpha, monocyte chemoattractant protein-1, and IL-6. Factors besides adiponectin, leptin, resistin, and tumor necrosis factor alpha appear to mediate these stimulatory effects. Our findings suggest that endothelial cell secretion is significantly influenced towards a proinflammatory pattern by adipocyte-secreted factors.


Subject(s)
Adipocytes/metabolism , Cytokines/metabolism , Endothelial Cells/metabolism , Paracrine Communication/immunology , Adipocytes/immunology , Cells, Cultured , Endothelial Cells/immunology , Endothelium, Vascular/cytology , Humans , Inflammation Mediators , Proteins/analysis , Proteins/metabolism , Proteomics , Up-Regulation
9.
Int J Cardiol ; 131(2): e59-60, 2009 Jan 09.
Article in English | MEDLINE | ID: mdl-17707527

ABSTRACT

Cardiac manifestations of hydatid cysts are rare and occur in about 0.2 to 3% of all cases of human hydatidosis. We report the case of a young man with a known 4-year old infection with Echinoccus granulosus. Cardiovascular magnetic resonance imaging (CMR) was performed and showed two cysts in the left ventricular wall. The smaller cyst had a thin, noncontinuous membrane to the left ventricle. The T1- and T2-weighted images showed an isointense signal of the cysts compared to blood; fat-suppressed images showed no fatty components. To highlight the potential small signal differences we assigned the contents of the gray images to red, green and blue channels of a conventional color image. Blood and the content of the cysts had the same color, making a connection between the cysts and the LV blood pool highly probable. This was confirmed by first pass perfusion imaging, which showed simultaneous contrast agent arrival in the left ventricular cavity and the cysts. Delayed enhancement (DE) revealed fibrotic tissue surrounding the cysts. MR seems to be the most complete method of diagnosing the disease, as anatomical structures, type of content of the cyst (liquid or solid) and its relation to the myocardium can be assessed within one study.


Subject(s)
Contrast Media , Echinococcosis/diagnosis , Echinococcosis/parasitology , Echinococcus granulosus , Magnetic Resonance Imaging , Ventricular Dysfunction, Left/diagnosis , Ventricular Dysfunction, Left/parasitology , Adult , Animals , Echinococcus granulosus/growth & development , Humans , Magnetic Resonance Imaging/methods , Male
10.
J Bacteriol ; 190(5): 1546-53, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18156273

ABSTRACT

Streptomyces davawensis synthesizes the antibiotic roseoflavin, one of the few known natural riboflavin analogs, and is roseoflavin resistant. It is thought that the endogenous flavokinase (EC 2.7.1.26)/flavin adenine dinucleotide (FAD) synthetase (EC 2.7.7.2) activities of roseoflavin-sensitive organisms are responsible for the antibiotic effect of roseoflavin, producing the inactive cofactors roseoflavin-5'-monophosphate (RoFMN) and roseoflavin adenine dinucleotide (RoFAD) from roseoflavin. To confirm this, the FAD-dependent Sus scrofa D-amino acid oxidase (EC 1.4.3.3) was tested with RoFAD as a cofactor and found to be inactive. It was hypothesized that a flavokinase/FAD synthetase (RibC) highly specific for riboflavin may be present in S. davawensis, which would not allow the formation of toxic RoFMN/RoFAD. The gene ribC from S. davawensis was cloned. RibC from S. davawensis was overproduced in Escherichia coli and purified. Analysis of the flavokinase activity of RibC revealed that the S. davawensis enzyme is not riboflavin specific (roseoflavin, kcat/Km = 1.7 10(-2) microM(-1) s(-1); riboflavin, kcat/Km = 7.5 10(-3) microM(-1) s(-1)). Similar results were obtained for RibC from the roseoflavin-sensitive bacterium Bacillus subtilis (roseoflavin, kcat/Km = 1.3 10(-2) microM(-1) s(-1); riboflavin, kcat/Km = 1.3 10(-2) microM(-1) s(-1)). Both RibC enzymes synthesized RoFAD and RoFMN. The functional expression of S. davawensis ribC did not confer roseoflavin resistance to a ribC-defective B. subtilis strain.


Subject(s)
Bacterial Proteins/metabolism , Flavins/metabolism , Nucleotidyltransferases/metabolism , Phosphotransferases (Alcohol Group Acceptor)/metabolism , Streptomyces/metabolism , Anti-Bacterial Agents/pharmacology , Bacillus subtilis/genetics , Bacillus subtilis/metabolism , Bacterial Proteins/genetics , Chromatography, High Pressure Liquid , Drug Resistance, Bacterial/genetics , Flavin Mononucleotide/chemistry , Flavin Mononucleotide/metabolism , Flavin-Adenine Dinucleotide/analogs & derivatives , Flavin-Adenine Dinucleotide/chemistry , Flavin-Adenine Dinucleotide/metabolism , Flavin-Adenine Dinucleotide/pharmacology , Flavins/chemistry , Genetic Complementation Test , Kinetics , Models, Genetic , Molecular Structure , Nucleotidyltransferases/genetics , Phosphotransferases (Alcohol Group Acceptor)/genetics , Riboflavin/analogs & derivatives , Riboflavin/pharmacology , Streptomyces/drug effects , Streptomyces/genetics
11.
JACC Cardiovasc Imaging ; 1(6): 729-38, 2008 Nov.
Article in English | MEDLINE | ID: mdl-19356509

ABSTRACT

OBJECTIVES: To evaluate in vivo anatomical relationships between the coronary sinus-great cardiac vein (CS-GCV), the mitral valve annulus (MVA), and left circumflex coronary artery (LCX) with cardiovascular magnetic resonance. BACKGROUND: The CS-GCV has become an anatomical structure of interest because it provides a way of access to the heart for a number of interventional procedures. Previous reports demonstrate that the postulated close anatomical proximity of the CS-GCV to the MVA does not always hold true in patients, both in autopsy specimens and in vivo by computed tomography. METHODS: In 31 participants (24 volunteers and 7 patients; 15 men; 42 +/- 19 years), cardiovascular magnetic resonance was performed for noninvasive evaluation of the coronary sinus and of the coronary arteries using whole-heart imaging and intravascular contrast agents. Three-dimensional reconstructions, standard orthogonal planes, and unprocessed raw data were used to assess CS-GCV anatomy and its relation to the MVA and the LCX along their entire course. RESULTS: The CS-GCV was located behind the left atrium in all examined participants, at a minimum distance of 8.6 +/- 3.9 mm from the MVA. In 80% of the participants, the LCX crossed the CS-GCV inferiorly, between the CS-GCV and the MVA. The CS-GCV and the LCX had a parallel course for 26.2 +/- 23.0 mm, with great variability of location and length. In several participants, the CS-GCV had a long parallel course, but in other participants, the LCX crossed below the CS-GCV at a discrete point. CONCLUSIONS: In all participants, the CS-GCV coursed behind the left atrium rather than behind the MVA. In the majority of the participants, the LCX coursed between the CS-GCV and the MVA. These anatomical relationships should be kept in mind when referring a patient for interventional procedures requiring the access to the CS-GCV, and cardiovascular magnetic resonance might provide important information for the selection of candidates for these procedures.


Subject(s)
Coronary Angiography/methods , Coronary Artery Disease/diagnosis , Coronary Vessels/pathology , Magnetic Resonance Angiography , Mitral Valve/pathology , Adult , Computer Simulation , Coronary Sinus/pathology , Feasibility Studies , Female , Humans , Image Interpretation, Computer-Assisted , Imaging, Three-Dimensional , Male , Middle Aged , Models, Cardiovascular , Retrospective Studies , Veins/pathology , Young Adult
12.
Atherosclerosis ; 196(2): 523-31, 2008 Feb.
Article in English | MEDLINE | ID: mdl-17603062

ABSTRACT

Hyperplasia and hypertrophy of fat cells can be found in obesity, and increased adiposity is associated with endothelial dysfunction as an early event of atherosclerosis. However, it is unclear whether human adipocytes directly influence endothelial function. To study the crosstalk between fat and endothelial cells, human umbilical venous endothelial cells (HUVECs), and human coronary artery endothelial cells (HCAECs) were cultured in infranatants (Adipo) of primary differentiated human adipocytes. Interestingly, incubation of HUVECs and HCAECs with Adipo significantly increased monocyte adhesion 7.3 and 2.2-fold, respectively. VCAM-1, ICAM-1, and E-selectin in HUVECs were upregulated 3.9, 3.0, and 9.5-fold, respectively, under these conditions. Furthermore, Adipo significantly stimulated NFkappaB activity 1.9-fold. The NFkappaB inhibitor MG-132 and heat inactivation significantly reversed Adipo-stimulated monocyte adhesion. TNFalpha-neutralizing antibodies partly reversed Adipo-induced monocyte adhesion. In contrast, thiazolidinedione-pretreatment of human adipocytes did not alter the effects of Adipo. Adipo did not show cytotoxic effects. Taken together, we demonstrate that endothelial dysfunction is induced by adipocyte-secreted factors via NFkappaB partly dependent on TNFalpha.


Subject(s)
Adipocytes/metabolism , Adipokines/physiology , Endothelium, Vascular/physiology , NF-kappa B/physiology , Adipocytes/drug effects , Apoptosis/drug effects , Cell Adhesion/drug effects , Cells, Cultured , E-Selectin/biosynthesis , Endothelium, Vascular/drug effects , Female , Humans , Intercellular Adhesion Molecule-1/biosynthesis , Leptin/pharmacology , Leupeptins/pharmacology , Resistin/pharmacology , Rosiglitazone , Thiazolidinediones/pharmacology , Tumor Necrosis Factor-alpha/physiology , Up-Regulation , Vascular Cell Adhesion Molecule-1/biosynthesis
13.
FEBS Lett ; 581(2): 279-83, 2007 Jan 23.
Article in English | MEDLINE | ID: mdl-17214985

ABSTRACT

The GcpE enzyme converts 2-C-methyl-D-erythritol-2,4-cyclodiphosphate (MEcPP) into (E)-4-hydroxy-3-methyl-but-2-enyl diphosphate (HMBPP) in the penultimate step of the DOXP pathway for isoprene biosynthesis. Purification of the enzyme under exclusion of air leads to a preparation that contains solely [4Fe-4S] clusters. Kinetic studies showed that in the presence of the artificial reductant dithionite and MEcPP a new transient iron-sulfur-based signal is detected in electron paramagnetic resonance (EPR) spectroscopy. Similarity of this EPR signal to that detected in ferredoxin:thioredoxin reductase indicates that during the reaction an intermediate is directly bound to the active-site cluster.


Subject(s)
Enzymes/chemistry , Erythritol/analogs & derivatives , Iron-Sulfur Proteins/chemistry , Thermus thermophilus/enzymology , Binding Sites , Electron Spin Resonance Spectroscopy , Enzymes/isolation & purification , Erythritol/metabolism , Iron/analysis , Iron-Sulfur Proteins/isolation & purification , Organophosphates/metabolism , Pentosephosphates/metabolism , Sulfur/analysis
14.
FEBS Lett ; 579(28): 6433-8, 2005 Nov 21.
Article in English | MEDLINE | ID: mdl-16289098

ABSTRACT

In the malaria parasite Plasmodium falciparum isoprenoid precursors are synthesised inside a plastid-like organelle (apicoplast) by the mevalonate independent 1-deoxy-d-xylulose-5-phosphate (DOXP) pathway. The last reaction step of the DOXP pathway is catalysed by the LytB enzyme which contains a [4Fe-4S] cluster. In this study, LytB of P. falciparum was shown to be catalytically active in the presence of an NADPH dependent electron transfer system comprising ferredoxin and ferredoxin-NADP(+) reductase. LytB and ferredoxin were found to form a stable protein complex. These data suggest that the ferredoxin/ferredoxin-NADP(+) reductase redox system serves as the physiological electron donor for LytB in the apicoplast of P. falciparum.


Subject(s)
Ferredoxin-NADP Reductase/metabolism , Ferredoxins/metabolism , Plasmodium falciparum/enzymology , Protozoan Proteins/metabolism , Terpenes/metabolism , Animals , Catalysis , Electron Transport , NADP/metabolism , Oxidation-Reduction , Paraquat/chemistry , Protozoan Proteins/genetics , Recombinant Proteins/genetics
15.
J Cardiovasc Magn Reson ; 7(2): 401-7, 2005.
Article in English | MEDLINE | ID: mdl-15881521

ABSTRACT

PURPOSE: With current noninvasive techniques compromises have to be accepted for coronary imaging, e.g., partial coverage of the coronary artery tree. The aim of the study was to estimate the potential intrinsic error of partial coverage from a database of invasive angiograms. METHODS AND RESULTS: The localization and severity of coronary artery stenoses and, if percutaneous coronary intervention (PCI) was performed, the balloon and stent size were extracted from a large database of 21,335 selective coronary angiograms. Of stenoses with >50% diameter reduction, 31.4% were located in distal segments and minor side branches, constituting 28.8% of interventional treatment. In 5% of patients undergoing their first invasive angiogram, the most proximal relevant stenosis was found in a distal segment or minor side branch. Most interventions (83.5%) were performed in main coronary artery segments. CONCLUSION: Coronary artery stenoses were found and interventional treatment performed in all coronary segments. Therefore, noninvasive coronary imaging of only proximal and medial segments and major side branches is an inadequate strategy for complete diagnosis or as a guide to therapeutic decisions. However, the currently available noninvasive techniques allow the detection of relevant stenoses in 95% of patients with suspected coronary artery disease (CAD) to prepare for further invasive diagnostic and therapeutic planning.


Subject(s)
Coronary Angiography , Coronary Stenosis/diagnostic imaging , Adolescent , Adult , Aged , Aged, 80 and over , Angioplasty, Balloon , Coronary Stenosis/therapy , Databases as Topic , Female , Humans , Male , Middle Aged , Sex Factors , Stents
16.
Plant J ; 42(3): 444-53, 2005 May.
Article in English | MEDLINE | ID: mdl-15842628

ABSTRACT

We have generated a novel genetic system to visualize cell lineages in living tissues at high resolution. Heat shock was used to trigger the excision of a specific transposon and activation of a fluorescent marker gene. A histone-YFP marker was used to allow identification of cell lineages and easy counting of cells. Constitutive expression of a green fluorescent membrane protein was used to provide a precise outline of all surrounding cells. Marked lineages can be induced from specific cells within the organism by targeted laser irradiation, and the fate of the marked cells can be followed non-invasively. We have used the system to map cell lineages originating from the initials of primary and lateral roots in Arabidopsis. The lineage marking technique enabled us to measure the differential contribution of primary root pericycle cell files to developing lateral root primordia. The majority of cells in an emerging lateral root primordium derive from the central file of pericycle founder cells while off-centre founder cells contribute only a minor proliferation of tissue near the base of the root. The system shows great promise for the detailed study of cell division during morphogenesis.


Subject(s)
Arabidopsis/cytology , Arabidopsis/growth & development , Cell Lineage/physiology , Botany/methods , Cell Differentiation , Cell Division , Genes, Reporter , Hot Temperature , Lasers , Luminescent Proteins/metabolism , Plant Roots/cytology , Plants, Genetically Modified , Recombinant Fusion Proteins/metabolism
17.
J Cardiovasc Magn Reson ; 6(4): 865-75, 2004.
Article in English | MEDLINE | ID: mdl-15646890

ABSTRACT

BACKGROUND: Magnetic resonance coronary angiography (MRCA) has traditionally been performed using a Cartesian k-space data acquisition scheme. Radial k-space sampling is known to be less sensitive to motion artifacts. Thus, potential improvements may be achieved with radial k-space data acquisition using steady state free precession (SSFP) techniques. We directly compared SSFP three-dimensional (3D)-MRCA using radial and Cartesian data acquisition. METHODS: Forty-four consecutive patients with suspected coronary artery disease underwent free-breathing, navigator-corrected MRCA of the left or right coronary artery using SSFP (TR/TE/flip angle: 4.5 ms/2.3 ms/90 degrees) with radial and again with Cartesian k-space filling. Quantitative MRCA was performed with a dedicated multiplanar reformatting software to determine: visual score for image quality (low=1, high=4), vessel sharpness, visible vessel length, number of visible side branches, and average vessel diameter. Diagnostic accuracy for detection of > or = 50% coronary artery stenosis was calculated in comparison to invasive X-ray angiography. RESULTS: Radial data acquisition resulted in a significant (p<0.01) increase in vessel sharpness (55.6+/-7.2% vs. 45.9+/-7.0%) but a decrease in average vessel diameter (2.6+/-0.5 mm vs. 3.0+/-0.4 mm), number of visible side branches (2.1+/-1.1 vs. 3.0+/-1.7) and number of assessable coronary artery segments (66% vs. 73%) compared to Cartesian approach. There was no significant difference regarding the diagnostic accuracy (80.8% vs. 83.9%), the visual score (2.6+/-0.9 vs. 3.0+/-0.9) and the visible vessel length (92.1+/-36.0 mm vs. 99.9+/-32.4 mm). CONCLUSIONS: MRCA with radial k-space sampling appears to be on a par with Cartesian approach with respect to the diagnostic performance in an unselected patient population. Nevertheless, with current implementations, radial sampling is inferior to Cartesian sampling regarding the visualization of side branches despite better vessel sharpness.


Subject(s)
Coronary Angiography , Coronary Stenosis/diagnosis , Magnetic Resonance Angiography , Adult , Aged , Aged, 80 and over , Artifacts , Coronary Stenosis/diagnostic imaging , Coronary Stenosis/pathology , Coronary Vessels/pathology , Female , Humans , Image Enhancement , Image Processing, Computer-Assisted , Male , Middle Aged , Predictive Value of Tests , Sensitivity and Specificity
19.
J Magn Reson Imaging ; 17(2): 153-62, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12541221

ABSTRACT

PURPOSE: To study pulsatile fluid flow in a physiologically realistic model of the human carotid bifurcation, and to derive wall shear stress (WSS) vectors. MATERIALS AND METHODS: WSS vectors were calculated from time-resolved 3D phase-contrast (PC) MRI measurements of the velocity field. The technique was first validated with sinusoidal flow in a straight tube, and then used in a model of a healthy human carotid bifurcation. Velocity measurements in the inflow and outflow regions were also used as boundary conditions for computational fluid dynamics (CFD) calculations of WSS, which were compared with those derived from MRI alone. RESULTS: The straight tube measurements gave WSS results that were within 15% of the theoretical value. WSS results for the phantom showed the main features expected from fluid dynamics, notably the low values in the bulb region of the internal carotid artery, with a return to ordered flow further downstream. MRI was not able to detect the high WSS values along the divider wall that were predicted by the CFD model. Otherwise, there was good general agreement between MRI and CFD. CONCLUSION: This is the first report of time-resolved WSS vectors estimated from 3D-MRI data. The technique worked well except in regions of disturbed flow, where the combination with CFD modeling is clearly advantageous.


Subject(s)
Carotid Arteries/physiology , Cerebrovascular Circulation , Magnetic Resonance Imaging , Models, Cardiovascular , Humans , Imaging, Three-Dimensional , Phantoms, Imaging , Pulsatile Flow
20.
Nucleic Acids Res ; 30(24): e141, 2002 Dec 15.
Article in English | MEDLINE | ID: mdl-12490732

ABSTRACT

Trans-splicing ribozymes are RNA-based catalysts capable of splicing RNA sequences from one transcript specifically into a separate target transcript. In doing so, a chimeric mRNA can be produced, and new gene activities triggered in living cells dependent on the presence of the target mRNA. Based on this ability of trans-splicing ribozymes to deliver new gene activities, a simple and versatile plating assay was developed in Saccharomyces cerevisiae for assessing and optimizing constructs in vivo. Trans-splicing ribozymes were used to splice sequences encoding a GAL4-derived transcription activator into a target transcript from a prevalent viral pathogen. The transcription activator translated from this new mRNA in turn triggered the expression of genes under the regulatory control of GAL4 upstream-activating sequences. Two of the activated genes complemented metabolic deficiencies in the host strain, and allowed growth on selective media. A simple genetic assay based on phenotypic conversion from auxotrophy to prototrophy was established to select efficient and specific trans-splicing ribozymes from a ribozyme library. This simple assay may prove valuable for selecting optimal target sites for therapeutic agents such as ribozymes, antisense RNA and antisense oligodeoxyribonucleotides, and for optimizing the design of the therapeutic agents themselves, in higher eukaryotes.


Subject(s)
RNA, Catalytic/metabolism , Saccharomyces cerevisiae/genetics , Cell Division/genetics , DNA-Binding Proteins , Genetic Complementation Test , Green Fluorescent Proteins , Luminescent Proteins/genetics , Luminescent Proteins/metabolism , Mutation , Plasmids/genetics , RNA, Catalytic/genetics , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Saccharomyces cerevisiae/growth & development , Saccharomyces cerevisiae Proteins/genetics , Saccharomyces cerevisiae Proteins/metabolism , Substrate Specificity , Transcription Factors/genetics , Transcription Factors/metabolism , Transformation, Genetic
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