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1.
Emerg Microbes Infect ; 12(1): 2164216, 2023 12.
Article in English | MEDLINE | ID: mdl-36580440

ABSTRACT

Ebolaviruses cause outbreaks of haemorrhagic fever in Central and West Africa. Some members of this genus such as Ebola virus (EBOV) are highly pathogenic, with case fatality rates of up to 90%, whereas others such as Reston virus (RESTV) are apathogenic for humans. Bombali virus (BOMV) is a novel ebolavirus for which complete genome sequences were recently found in free-tailed bats, although no infectious virus could be isolated. Its pathogenic potential for humans is unknown. To address this question, we first determined whether proteins encoded by the available BOMV sequence found in Chaerephon pumilus were functional in in vitro assays. The correction of an apparent sequencing error in the glycoprotein based on these data then allowed us to generate infectious BOMV using reverse genetics and characterize its infection of human cells. Furthermore, we used HLA-A2-transgenic, NOD-scid-IL-2γ receptor-knockout (NSG-A2) mice reconstituted with human haematopoiesis as a model to evaluate the pathogenicity of BOMV in vivo in a human-like immune environment. These data demonstrate that not only does BOMV show a slower growth rate than EBOV in vitro, but it also shows low pathogenicity in humanized mice, comparable to previous studies using RESTV. Taken together, these findings suggest a low pathogenic potential of BOMV for humans.


Subject(s)
Ebolavirus , Hemorrhagic Fever, Ebola , Humans , Animals , Mice , Ebolavirus/genetics , Mice, Inbred NOD , Animals, Genetically Modified , Africa, Western
2.
Nanotoxicology ; 13(5): 606-622, 2019 06.
Article in English | MEDLINE | ID: mdl-30760076

ABSTRACT

Modified nanoparticles (NPs) can interact with the immune system by causing its activation to fight tumors or for vaccination. During this activation, dendritic cells (DCs) are effective in generating robust immune response. However, the effect of nanomaterials on dendritic cell (DC) maturation, and the associated adjuvant effect, should be assessed as a novel biocompatibility criteria for biomaterials since immune consequences may constitute potential complications in nanomedicine. Among emerging biomaterials, poly(lactic-co-glycolic acid) NPs (PLGA NPs) are widely explored for various applications in which the degree of desired adjuvant effect may vary. As contradictory results are reported regarding their effects on DCs, we aimed at clarifying this point with particular emphasis on the relative impact of particle surface properties. To that end, NP uptake and effects on the viability, phenotype, and secretory activity of DC primary cultures. Intracellular signaling pathways were explored and evaluated. Immature human and murine DCs were exposed to cationic, neutral, or anionic PLGA NPs. Particle uptake was assessed by both confocal microscopy and flow cytometry. Cell viability was then evaluated prior to the study of maturation by examination of both surface marker expression and cytokine release. Our results demonstrate that PLGA NPs are rapidly engulfed by DCs and do not exert cytotoxic effects. However, upon exposure to PLGA NPs, DCs showed phenotypes and cytokine secretion profiles consistent with maturation which resulted, at least in part, from the transient intracellular activation of mitogen-activated protein kinases (MAPKs). Interestingly, NP-specific stimulation patterns were observed since NP surface properties had a sensible influence on the various parameters measured.


Subject(s)
Biocompatible Materials/toxicity , Dendritic Cells/drug effects , Nanoparticles/toxicity , Phagocytosis/drug effects , Polylactic Acid-Polyglycolic Acid Copolymer/toxicity , Animals , Biocompatible Materials/chemistry , CD4-Positive T-Lymphocytes/drug effects , CD4-Positive T-Lymphocytes/immunology , Cell Proliferation/drug effects , Cell Survival/drug effects , Cell Survival/immunology , Coculture Techniques , Cytokines/metabolism , Dendritic Cells/immunology , Humans , Mice , Mice, Inbred C57BL , Nanoparticles/chemistry , Phagocytosis/immunology , Polylactic Acid-Polyglycolic Acid Copolymer/chemistry , Polylactic Acid-Polyglycolic Acid Copolymer/immunology , Surface Properties
3.
J Chem Phys ; 149(17): 174101, 2018 Nov 07.
Article in English | MEDLINE | ID: mdl-30408993

ABSTRACT

We report on first applications of the Two-Layer Gaussian-based Multi-Configuration Time-Dependent Hartree (2L-GMCTDH) method [Römer et al., J. Chem. Phys. 138, 064106 (2013)] for high-dimensional quantum propagation using variational Gaussian basis sets. This method circumvents the limitations of conventional variational Gaussian wavepacket (GWP) methods by introducing a hierarchical wavefunction representation with a fully flexible first layer composed of orthogonal single-particle functions, which are in turn expressed as superpositions of GWPs of fixed width. The method is applied to a model Hamiltonian describing vibrational energy transport through a molecular chain. The model combines bilinear site-to-site couplings with site-local couplings induced by cubic anharmonicities. We report on simulation results for realizations comprising 5 sites with 35 vibrational modes and 18 sites with 90 vibrational modes, which are shown to be in excellent agreement with reference calculations by the Multi-Layer MCTDH method.

4.
Free Radic Biol Med ; 110: 1-10, 2017 09.
Article in English | MEDLINE | ID: mdl-28457937

ABSTRACT

The redox-sensitive nuclear factor erythroid-derived 2-like 2 (NRF2) controls endogenous antioxidant enzymes' transcription and protects against oxidative damage which is triggered by inflammation and known to favor progression of endometriosis. Glutamate Cysteine Ligase (GCL), a target gene of NRF2, is the first enzyme in the synthesis cascade of glutathione, an important endogenous antioxidant. Sixty-one patients, with thorough surgical examination of the abdominopelvic cavity, were recruited for the study: 31 with histologically-proven endometriosis and 30 disease-free women taken as controls. Expressions of NRF2 and GCL were investigated by quantitative RT-PCR and immunohistochemistry in eutopic and ectopic endometria from endometriosis-affected women and in endometrium of disease-free women. Ex vivo stromal and epithelial cells were extracted and purified from endometrial and endometriotic biopsies to explore expression of NRF2 and GCL in both stromal and epithelial compartments by western blot. Finally, in order to strengthen the role of NRF2 in endometriosis pathogenesis, we evaluated the drop of NRF2 expression in a mouse model of endometriosis using NRF2 knockout (NRF2-/-) mice. The mRNA levels of NRF2 and GCL were significantly lower in ectopic endometria of endometriosis-affected women compared to eutopic endometria of disease-free women. The immunohistochemical analysis confirmed the decreased expression of both NRF2 and GCL in ectopic endometriotic tissues compared to eutopic endometria of endometriosis-affected and disease-free women. Immunoblotting revealed a significant decreased of NRF2 and GCL expression in epithelial and stroma cells from ectopic lesions of endometriosis-affected women compared to eutopic endometria from controls. Using a murine model of endometriosis, NRF2-/- implants were more fibrotic compared to wild-type with an increased weight and volume. These findings indicate that expression of the transcription factor NRF2 and its effector GCL are both profoundly deregulated in endometriotic lesions towards increased growth and fibrogenetic processes.


Subject(s)
Choristoma/genetics , Endometriosis/genetics , Endometrium/metabolism , Glutamate-Cysteine Ligase/genetics , NF-E2-Related Factor 2/genetics , Adult , Animals , Case-Control Studies , Choristoma/metabolism , Choristoma/pathology , Disease Models, Animal , Endometriosis/metabolism , Endometriosis/pathology , Endometrium/pathology , Epithelial Cells/metabolism , Epithelial Cells/pathology , Female , Fibrosis , Gene Expression Regulation , Glutamate-Cysteine Ligase/metabolism , Humans , Mice , Mice, Inbred C57BL , Mice, Knockout , NF-E2-Related Factor 2/deficiency , NF-E2-Related Factor 2/metabolism , Oxidative Stress , Primary Cell Culture , Prospective Studies , Stromal Cells/metabolism , Stromal Cells/pathology , Tertiary Care Centers
5.
Sci Rep ; 7: 41580, 2017 01 30.
Article in English | MEDLINE | ID: mdl-28134299

ABSTRACT

90Sr is one of the radionuclides released after nuclear accidents that can significantly impact human health in the long term. 90Sr accumulates mostly in the bones of exposed populations. Previous research has shown that exposure induces changes in bone physiology both in humans and in mice. We hypothesize that, due to its close location with bone marrow stromal cells (BMSCs), 90Sr could induce functional damage to stromal cells that may explain these biological effects due to chronic exposure to 90Sr. The aim of this work was to verify this hypothesis through the use of an in vitro model of MS5 stromal cell lines exposed to 1 and 10 kBq.mL-1 of 90Sr. Results indicated that a 30-minute exposure to 90Sr induced double strand breaks in DNA, followed by DNA repair, senescence and differentiation. After 7 days of exposure, MS5 cells showed a decreased ability to proliferate, changes in cytokine expression, and changes in their ability to support hematopoietic progenitor proliferation and differentiation. These results demonstrate that chronic exposure to a low concentration of 90Sr can induce functional changes in BMSCs that in turn may explain the health effects observed in following chronic 90Sr exposure.


Subject(s)
DNA Damage/drug effects , Mesenchymal Stem Cells/drug effects , Mesenchymal Stem Cells/metabolism , Strontium Radioisotopes/pharmacology , Analysis of Variance , Animals , Cell Death , Cell Differentiation/drug effects , Cell Proliferation/drug effects , Cellular Senescence/drug effects , Cytokines/metabolism , DNA Breaks, Double-Stranded/drug effects , DNA Repair , Histones/metabolism , Humans , Oxidation-Reduction/drug effects , Rats , Reactive Oxygen Species/metabolism
6.
Med Klin Intensivmed Notfmed ; 110(6): 445-51, 2015 Sep.
Article in German | MEDLINE | ID: mdl-25676119

ABSTRACT

BACKGROUND: Systemic thrombolysis was introduced as the sole prehospital treatment option in patients with cardiac arrest in the setting of acute myocardial ischemia or pulmonary embolism; however, it remains the subject of discussion. PATIENTS AND METHODS: A total of 194 patients with sudden prehospital cardiac arrest were included in this retrospective case control study. Of these patients, 96 in whom circulatory arrest due to cardiac disease (pulmonary artery embolism or myocardial ischemia) was suspected underwent thrombolytic treatment and were compared to the remaining 98 patients that did not undergo thrombolytic therapy. In addition to the circumstances of circulatory arrest, the course and success of resuscitation, as well as in-hospital course (including bleeding complications), overall survival and neurological outcomes were compared. RESULTS: There were no significant differences between patients with or without thrombolysis in terms of the circumstances of cardiac arrest. Patients that received thrombolytic treatment were significantly younger and were more frequently treated with anticoagulants, platelet aggregation inhibitors and amiodarone. They also received higher doses of epinephrine and arrived at hospital under ongoing resuscitation significantly more frequently. A trend toward more prehospital return of spontaneous circulation (ROSC) following thrombolytic treatment was seen in the entire cohort. However, patients pre-treated with acetylsalicylic acid and heparin did not show better prehospital ROSC rates as a result of additional thrombolytic therapy. Significant differences in terms of bleeding complications or the need for blood transfusion could not be seen due to the small number of patients. DISCUSSION: The indication for systemic thrombolysis in the context of prehospital resuscitation should remain restricted to patients with clear symptoms of acute pulmonary embolism or recurrent episodes of ventricular fibrillation in the setting of acute myocardial infarction. Due to a lack of evidence, systemic thrombolysis should not be used as a treatment of last resort in younger patients with persistent ventricular fibrillation.


Subject(s)
Critical Care , Emergency Medical Services/methods , Heart Arrest/therapy , Myocardial Infarction/therapy , Pulmonary Embolism/therapy , Resuscitation/methods , Thrombolytic Therapy/methods , Adult , Aged , Aged, 80 and over , Case-Control Studies , Cohort Studies , Female , Germany , Heart Arrest/mortality , Hemorrhage/chemically induced , Humans , Male , Middle Aged , Myocardial Infarction/mortality , Pulmonary Embolism/mortality , Retrospective Studies , Survival Rate , Thrombolytic Therapy/adverse effects
7.
Faraday Discuss ; 163: 205-22; discussion 243-75, 2013.
Article in English | MEDLINE | ID: mdl-24020204

ABSTRACT

We present a quantum dynamical study of exciton transfer across a torsional defect that locally breaks the pi-conjugation in an oligo-(p-phenylene vinylene) (OPV) fragment. A site-based vibronic coupling Hamiltonian is used which is formulated in a comparative fashion (i) for a Frenkel exciton basis, assuming localized electron-hole pairs whose superposition yields a delocalized exciton, and (ii) more accurately, for a Merrifield type exciton basis including spatially separated electron-hole pairs. Starting from a partially delocalized ("spectroscopic unit") initial condition, the observed transfer dynamics is found to involve two characteristic time scales: (i) a very rapid, coherent transient on a 10-100 femtosecond scale, largely determined by Rabi type oscillations modulated by bond-length-alternation modes, and (ii) a slower time scale involving the planarization of the torsional coordinates that determines the onset of a quasi-stationary exciton-polaron state, and in the process leads to a "healing" of the torsional defect within - 500 femtoseconds. The dynamics obtained from the full electron-hole basis vs. Frenkel basis are in good agreement. In the full electron-hole dynamics, the transients are found to involve a rapid expansion and subsequent contraction of the electron-hole coherence size. Quantum dynamical simulations for a minimal six-site model involving 36 states and 22 vibrational modes, were carried out using the multiconfiguration time dependent Hartree (MCTDH) method.

8.
J Adolesc Health ; 52(4 Suppl): S35-9, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23535055

ABSTRACT

Adolescents and young women were historically excluded from receiving long-acting reversible contraceptives (LARC) such as intrauterine devices (IUDs) after widespread concerns about infection and infertility 40 years ago reduced IUD use for all women. Over the last several years, concerted efforts by professional health organizations have promoted LARC as an excellent solution to the epidemic of unintended pregnancy in adolescents and young adults, yet uptake has increased slowly. In this article we review evidence regarding awareness of LARC among young women, and perceptions and knowledge of LARC in this population. We review evidence on clinical providers' knowledge and beliefs about LARC, and their beliefs about the appropriateness or risks of LARCs for adolescents and young women. We discuss an active role for providers in increasing awareness of LARC among young women, rather than relying on patient request for methods of which they have little knowledge. Finally, we suggest avenues of future research into the most effective and efficient ways to increase awareness of LARC among adolescents.


Subject(s)
Health Knowledge, Attitudes, Practice , Intrauterine Devices , Adolescent , Female , Humans , Pregnancy , Pregnancy in Adolescence/prevention & control , Pregnancy, Unwanted , Young Adult
9.
J Chem Phys ; 138(6): 064106, 2013 Feb 14.
Article in English | MEDLINE | ID: mdl-23425460

ABSTRACT

We describe a novel two-layer variant of the Gaussian-based multiconfiguration time-dependent Hartree (G-MCTDH) approach which improves on the performance and convergence properties of quantum propagation based on variationally evolving frozen Gaussians (FGs). While the standard scheme uses factorizable multi-dimensional FGs, the present approach combines these into flexible, MCTDH-like single-particle functions. At the same time, the expensive variational evolution of the Gaussian parameters is reduced to low-dimensional subspaces. As a result, the novel scheme significantly alleviates the current bottleneck to accurate propagation in G-MCTDH and its variational multiconfigurational Gaussian (vMCG) variant. Since the first-layer single-particle functions are chosen to be orthogonal, the present approach can be straightforwardly combined with existing multi-layer MCTDH schemes.

10.
Chemistry ; 16(24): 7208-14, 2010 Jun 25.
Article in English | MEDLINE | ID: mdl-20461832

ABSTRACT

BeP(2)N(4) was synthesized in a multi-anvil apparatus starting from Be(3)N(2) and P(3)N(5) at 5 GPa and 1500 degrees C. The compound crystallizes in the phenakite structure type (space group R3, no. 148) with a=1269.45(2) pm, c=834.86(2) pm, V=1165.13(4) x 10(6) pm(3) and Z=18. As isostructural and isovalence-electronic alpha-Si(3)N(4) transforms into beta-Si(3)N(4) at high pressure and temperature, we studied the phase transition of BeP(2)N(4) into the spinel structure type by using density functional theory calculations. The predicted transition pressure of 24 GPa is within the reach of today's state of the art high-pressure experimental setups. Calculations of inverse spinel-type BeP(2)N(4) revealed this polymorph to be always higher in enthalpy than either phenakite-type or spinel-type BeP(2)N(4). The predicted bulk modulus of spinel-type BeP(2)N(4) is in the range of corundum and gamma-Si(3)N(4) and about 40 GPa higher than that of phenakite-type BeP(2)N(4). This finding implies an increase in hardness in analogy to that occurring for the beta- to gamma-Si(3)N(4) transition. In hypothetical spinel-type BeP(2)N(4) the coordination number of phosphorus is increased from 4 to 6. So far only coordination numbers up to 5 have been experimentally realized (gamma-P(3)N(5)), though a sixfold coordination for P has been predicted for hypothetic delta-P(3)N(5). We believe, our findings provide a strong incentive for further high-pressure experiments in the quest for novel hard materials with yet unprecedented structural motives.

11.
Phys Rev Lett ; 105(19): 197201, 2010 Nov 05.
Article in English | MEDLINE | ID: mdl-21231192

ABSTRACT

For a fixed 2 µm×2 µm area of a Co/Pt-CoO perpendicular exchange bias system we image the ferromagnetic (FM) domains for various applied fields with 10-nm resolution by magnetic force microscopy (MFM). Using quantitative MFM we measure the local areal density of pinned uncompensated spins (pinUCS) in the antiferromagnetic (AFM) CoO layer and correlate the FM domain structure with the UCS density. Larger applied fields drive the receding domains to areas of proportionally higher pinUCS aligned antiparallel to FM moments. The data confirm that the evolution of the FM domains is determined by the pinUCS in the AFM layer, and also present examples of frustration in the system.

12.
Int J Androl ; 33(1): e240-8, 2010 Feb.
Article in English | MEDLINE | ID: mdl-19863670

ABSTRACT

Sperm chromatin compaction in the sperm head is achieved when histones are replaced by protamines during spermatogenesis. Haploinsufficiency of the protamine 1 (PRM1) or PRM2 gene causes infertility in mice. However, the published data remain inconclusive about a role of PRM1/2 variants in male infertility and their association with semen parameters. By full sequence analysis, we assessed the frequency of sequence variations in PRM1 and PRM2 in three groups of Caucasian patients with idiopathic teratozoospermia and normal (n = 88) or reduced sperm concentration (n = 83) and in men with a high percentage of normal sperm morphology and normal concentrations (n = 77). Two rare (c.54G>A and c.102G>T) and one common SNP (c.230A>C) were identified in PRM1. In PRM2, some rare heterozygous mutations and the two common intronic SNPs 298G>C and 373C>A were detected. None of the PRM1/2 variants was associated with teratozoospermia or individually with other semen parameters. However, significant linkage disequilibrium was detected between the common SNPs of PRM1 and PRM2 which formed haplotypes. Analysis of the pooled group (n = 248) revealed that homozygous carriers of the common haplotype ACC had a twofold higher sperm concentration and count than men lacking this haplotype, with sperm counts of heterozygotes for ACC being midway between the homozygotes. This markedly decreased sperm output might either be caused by spermatozoa lacking the ACC haplotype not being viable, or subject to negative selection. In addition, a significant deviation from Hardy-Weinberg-Equilibrium of these SNPs might indicate natural selection in favour of the ACC allele which leads to higher sperm output and therefore better fertility. In conclusion, for the first time we describe an association of a common haplotype formed by PRM1 and PRM2 with sperm output in a large group of men.


Subject(s)
Protamines/genetics , Adult , Chromatin/metabolism , Fertility/genetics , Genes , Haplotypes , Heterozygote , Histones/genetics , Humans , Infertility, Male/genetics , Male , Middle Aged , Mutation , Polymorphism, Single Nucleotide/genetics , Spermatogenesis/genetics , Spermatozoa
13.
J Phys Condens Matter ; 21(27): 275407, 2009 Jul 08.
Article in English | MEDLINE | ID: mdl-21828491

ABSTRACT

Normal pressure modifications and tentative high-pressure phases of the nitridosilicates MSiN(2) with M =  Be, Mg, or Ca have been thoroughly studied by density functional methods. At ambient pressure, BeSiN(2) and MgSiN(2) exhibit an ordered wurtzite variant derived from idealized filled ß-cristobalite by a C1-type distortion. At ambient pressure, the structure of CaSiN(2) can also be derived from idealized filled ß-cristobalite by a different type of distortion (D1-type). Energy-volume calculations for all three compounds reveal transition into an NaCl superstructure under pressure, affording sixfold coordination for Si. At 76 GPa BeSiN(2) forms an LiFeO(2)-type structure, corresponding to the stable ambient-pressure modification of LiFeO(2), while MgSiN(2) and CaSiN(2) adopt an LiFeO(2)-type structure, corresponding to a metastable modification (24 and 60 GPa, respectively). For both BeSiN(2) and CaSiN(2) intermediate phases appear (for BeSiN(2) a chalcopyrite-type structure and for CaSiN(2) a CaGeN(2)-type structure). These two tetragonal intermediate structures are closely related, differing mainly in their c/a ratio. As a consequence, chalcopyrite-type structures exhibit tetrahedral coordination for both cations (M and Si), whereas in CaGeN(2)-type structures one cation is tetrahedrally (Si) and one bisdisphenoidally (M) coordinated. Both structure types, chalcopyrite and CaGeN(2), can also be derived from idealized filled ß-cristobalite through a B1-type distortion. The group-subgroup relation of the BeSiN(2)/MgSiN(2), the CaSiN(2), the chalcopyrite, the CaGeN(2) and the idealized filled ß-cristobalite structure is discussed and the displacive phase transformation pathways are illustrated. The zero-pressure bulk moduli were calculated for all phases and have been found to be comparable to compounds such as α- Si(3)N(4), CaIrO(3) and Al(4)C(3). Furthermore, the thermodynamic stability of BeSiN(2), MgSiN(2) and CaSiN(2) against phase agglomerates of the binary nitrides M(3)N(2) and Si(3)N(4) under pressure are examined.

14.
J Phys Condens Matter ; 21(27): 275408, 2009 Jul 08.
Article in English | MEDLINE | ID: mdl-21828492

ABSTRACT

We investigate the high-pressure phase diagram of SrSiN(2) and BaSiN(2) with density-functional calculation. Searching a manifold of possible candidate structures, we propose new structural modifications of SrSiN(2) and BaSiN(2) attainable in high-pressure experiments. The monoclinic ground state of SrSiN(2) transforms at 3 GPa into an orthorhombic BaSiN(2) type. At 14 GPa a CaSiN(2)-type structure becomes the most stable configuration of SrSiN(2). A hitherto unknown Pbcm modification is adopted at 85 GPa and, finally, at 131 GPa a LiFeO(2)-type structure. The higher homologue BaSiN(2) transforms to a CaSiN(2) type at 41 GPa and further to a Pbcm modification at 105 GPa. Both systems follow the pressure-coordination rule: the coordination environment of Si increases from tetrahedral through trigonal bipyramidal to octahedral. Some high-pressure phases are related in structure through simple group-subgroup mechanisms, indicating displacive phase transformations with low activation barriers.

15.
Chemistry ; 14(26): 7892-902, 2008.
Article in English | MEDLINE | ID: mdl-18624300

ABSTRACT

HP-Ca2Si5N8 was obtained by means of high-pressure high-temperature synthesis utilizing the multianvil technique (6 to 12 GPa, 900 to 1200 degrees C) starting from the ambient-pressure phase Ca2Si5N8. HP-Ca2Si5N8 crystallizes in the orthorhombic crystal system (Pbca (no. 61), a=1058.4(2), b=965.2(2), c=1366.3(3) pm, V=1395.7(7)x10(6) pm3, Z=8, R1=0.1191). The HP-Ca2Si5N8 structure is built up by a three-dimensional, highly condensed nitridosilicate framework with N[2] as well as N[3] bridging. Corrugated layers of corner-sharing SiN4 tetrahedra are interconnected by further SiN4 units. The Ca2+ ions are situated between these layers with coordination numbers 6+1 and 7+1, respectively. HP-Ca2Si5N8 as well as hypothetical orthorhombic o-Ca2Si5N8 (isostructural to the ambient-pressure modifications of Sr2Si5N8 and Ba2Si5N8) were studied as high-pressure phases of Ca2Si5N8 up to 100 GPa by using density functional calculations. The transition pressure into HP-Ca2Si5N8 was calculated to 1.7 GPa, whereas o-Ca2Si5N8 will not be adopted as a high-pressure phase. Two different decomposition pathways of Ca2Si5N8 (into Ca3N2 and Si3N4 or into CaSiN2 and Si3N4) and their pressure dependence were examined. It was found that a pressure-induced decomposition of Ca2Si5N8 into CaSiN2 and Si3N4 is preferred and that Ca2Si5N8 is no longer thermodynamically stable under pressures exceeding 15 GPa. Luminescence investigations (excitation at 365 nm) of HP-Ca2Si5N8:Eu2+ reveal a broadband emission peaking at 627 nm (FWHM=97 nm), similar to the ambient-pressure phase Ca2Si5N8:Eu2+.

17.
Ultrasound Obstet Gynecol ; 28(6): 842-4, 2006 Nov.
Article in English | MEDLINE | ID: mdl-17063449

ABSTRACT

Agenesis of the superior vena cava is a rare anomaly that is generally asymptomatic in the neonate. We report a male neonate with bilateral (total) agenesis of the superior vena cava with obstructed thoracic duct and subsequent congenital hydrothorax, anomalies that were detected by prenatal ultrasound at 25 weeks' gestation. The cardiac anomaly was confirmed by postnatal magnetic resonance angiography. The chylothorax disappeared with conservative therapy.


Subject(s)
Chylothorax/congenital , Hydrothorax/congenital , Thoracic Duct , Vena Cava, Superior/abnormalities , Adult , Chylothorax/diagnosis , Constriction, Pathologic/diagnosis , Female , Humans , Hydrothorax/diagnosis , Infant, Newborn , Magnetic Resonance Angiography/methods , Male , Pregnancy , Treatment Outcome , Ultrasonography, Prenatal
18.
Cephalalgia ; 23(9): 921-8, 2003 Nov.
Article in English | MEDLINE | ID: mdl-14616935

ABSTRACT

In order to better understand sporadic hemiplegic migraine (SHM) and particularly its relation to familial hemiplegic migraine (FHM), migraine without aura (MO) and typical migraine with aura (typical MA), we investigated the occurrence of MO and typical MA among probands with SHM and their first-degree relatives. The pattern of familial aggregation of MO and typical MA was assessed by population relative risk calculations. A total of 105 SHM probands and 483 first-degree relatives were identified in the Danish population. Compared with the general population, SHM probands had no increased risk of MO, but a highly increased risk of typical MA. First-degree relatives of all SHM probands had an increased risk of both MO and typical MA, whereas first-degree relatives of probands with exclusively SHM had no increased risk of MO but an increased risk of typical MA. Our data suggest that SHM is a genetically heterogeneous disorder.


Subject(s)
Migraine with Aura/epidemiology , Migraine with Aura/etiology , Adolescent , Adult , Age Factors , Child , Child, Preschool , Denmark/epidemiology , Family , Female , Genetic Predisposition to Disease , Hemiplegia/etiology , Humans , Infant , Infant, Newborn , Male , Middle Aged , Risk Factors , Sex Factors
19.
Planta ; 217(6): 896-903, 2003 Oct.
Article in English | MEDLINE | ID: mdl-12844264

ABSTRACT

A characteristic trait of the high pigment-1 ( hp-1) mutant phenotype of tomato ( Lycopersicon esculentum Mill.) is increased pigmentation resulting in darker green leaves and a deeper red fruit. In order to determine the basis for changes in pigmentation in this mutant, cellular and plastid development was analysed during leaf and fruit development, as well as the expression of carotenogenic genes and phytoene synthase enzyme activity. The hp-1 mutation dramatically increases the periclinal elongation of leaf palisade mesophyll cells, which results in increased leaf thickness. In addition, in both palisade and spongy mesophyll cells, the total plan area of chloroplasts per cell is increased compared to the wild type. These two perturbations in leaf development are the primary cause of the darker green hp-1 leaf. In the hp-1 tomato fruit, the total chromoplast area per cell in the pericarp cells of the ripe fruit is also increased. In addition, although expression of phytoene synthase and desaturase is not changed in hp-1 compared to the wild type, the activity of phytoene synthase in ripe fruit is 1.9-fold higher, indicating translational or post-translational control of carotenoid gene expression. The increased plastid compartment size in leaf and fruit cells of hp-1 is novel and provides evidence that the normally tightly controlled relationship between cell expansion and the replication and expansion of plastids can be perturbed and thus could be targeted by genetic manipulation.


Subject(s)
Alkyl and Aryl Transferases/metabolism , Plastids/ultrastructure , Solanum lycopersicum/growth & development , Solanum lycopersicum/genetics , Alkyl and Aryl Transferases/genetics , Base Sequence , Carotenoids/metabolism , Chlorophyll/metabolism , DNA Primers , Geranylgeranyl-Diphosphate Geranylgeranyltransferase , Solanum lycopersicum/ultrastructure , Oxidoreductases/genetics , Oxidoreductases/metabolism , Phenotype , Plant Leaves/enzymology , Polymerase Chain Reaction , Seeds/physiology
20.
Cell Death Differ ; 10(7): 833-44, 2003 Jul.
Article in English | MEDLINE | ID: mdl-12815466

ABSTRACT

The transmembrane receptor Notch1 plays a crucial role in differentiation and apoptosis of hematopoietic cells. To investigate the influence of Notch1 on apoptosis and cell growth of mature murine B cells, we transduced the murine B-lymphoma line NYC 31.1 with a constitutively active, intracellular form of human Notch1 (Notch1-ICT). NYC cells represent mature activated B cells that can be induced to undergo apoptosis by crosslinking of the B-cell receptor (BCR). In contrast to investigations in immature chicken B-cell lines, transduced Notch1-ICT did not affect cell cycle progression, cell growth or surface IgM levels in NYC cells and resulted only in a slight induction of apoptosis. However, BCR-crosslinking enhanced apoptosis, but did not influence cell cycle progression in Notch1-ICT-positive NYC cells. These data imply a distinct function of Notch1 in mature murine B-cells as compared to immature chicken B cells and provide further evidence for Notch1's involvement in B-cell differentiation and development.


Subject(s)
Apoptosis/immunology , B-Lymphocytes/metabolism , Immunoglobulin M/metabolism , Receptors, Antigen, B-Cell/metabolism , Receptors, Cell Surface/metabolism , Transcription Factors , Animals , Apoptosis/genetics , B-Lymphocytes/immunology , Cell Cycle/genetics , Cell Cycle/immunology , Cell Differentiation/genetics , Cell Differentiation/immunology , Cell Line, Tumor , Chickens , Hematopoiesis/genetics , Hematopoiesis/immunology , Mice , Receptor, Notch1 , Receptors, Cell Surface/genetics , Species Specificity , Transduction, Genetic , Up-Regulation/genetics , Up-Regulation/immunology
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