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1.
Clin Pharmacol Ther ; 103(2): 341-348, 2018 02.
Article in English | MEDLINE | ID: mdl-28543042

ABSTRACT

Myrcludex B acts as a hepatitis B and D virus entry inhibitor blocking the sodium taurocholate cotransporting polypeptide (SLC10A1). We investigated the effects of myrcludex B on plasma bile acid disposition, tenofovir pharmacokinetics, and perpetrator characteristics on cytochrome P450 (CYP) 3A. Twelve healthy volunteers received 300 mg tenofovir disoproxil fumarate orally and 10 mg subcutaneous myrcludex B. Myrcludex B increased total plasma bile acid exposure 19.2-fold without signs of cholestasis. The rise in conjugated bile acids was up to 124-fold (taurocholic acid). Coadministration of tenofovir with myrcludex B revealed no relevant changes in tenofovir pharmacokinetics. CYP3A activity slightly but significantly decreased by 29% during combination therapy. Myrcludex B caused an asymptomatic but distinct rise in plasma bile acid concentrations and had no relevant impact on tenofovir pharmacokinetics. Changes in CYP3A activity might be due to alterations in bile acid signaling. Long-term effects of elevated bile acids will require critical evaluation.


Subject(s)
Antiviral Agents/administration & dosage , Bile Acids and Salts/blood , Lipopeptides/administration & dosage , Reverse Transcriptase Inhibitors/pharmacokinetics , Tenofovir/pharmacokinetics , Administration, Oral , Adult , Antiviral Agents/adverse effects , Antiviral Agents/pharmacokinetics , Biomarkers/blood , Cytochrome P-450 CYP3A/metabolism , Drug Interactions , Female , Humans , Injections, Subcutaneous , Lipopeptides/adverse effects , Lipopeptides/pharmacokinetics , Male , Middle Aged , Organic Anion Transporters, Sodium-Dependent/antagonists & inhibitors , Organic Anion Transporters, Sodium-Dependent/metabolism , Prospective Studies , Reverse Transcriptase Inhibitors/administration & dosage , Reverse Transcriptase Inhibitors/adverse effects , Risk Assessment , Symporters/antagonists & inhibitors , Symporters/metabolism , Tenofovir/administration & dosage , Tenofovir/adverse effects , Up-Regulation , Young Adult
2.
Clin Exp Allergy ; 47(10): 1331-1341, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28802077

ABSTRACT

BACKGROUND: Food allergy is an increasingly common health problem in Western populations. Epidemiological studies have suggested both positive and negative associations between food allergy and infection with the gastric bacterium Helicobacter pylori. OBJECTIVE: The objective of this work was to investigate whether experimental infection with H. pylori, or prophylactic treatment with H. pylori-derived immunomodulatory molecules, affects the onset and severity of food allergy, either positively or negatively. METHODS: We infected neonatal C57BL/6 or C3H mice with H. pylori or treated animals with H. pylori components (bacterial lysate or the immunomodulator VacA) and subsequently subjected them to four different protocols for food allergy induction, using either ovalbumin or peanut extract as allergens for sensitization and challenge. Readouts included anaphylaxis scoring, quantification of allergen-specific serum IgE and IgG1 and of the mast cell protease MCPT1, as well as splenic T-helper-2 cell-derived cytokine production. Mesenteric lymph node CD4+ FoxP3+ regulatory T cells were subjected to flow cytometric quantification and sorting followed by qRT-PCR, and to DNA methylation analyses of the Treg-specific demethylated region (TSDR) within the FOXP3 locus. RESULTS: Mice that had been infected with H. pylori or treated with H. pylori-derived immunomodulators showed reduced anaphylaxis upon allergen sensitization and challenge, irrespective of the allergen used. Most of the immunologic assays confirmed a protective effect of H. pylori. CD4+ FoxP3+ T cells were more abundant in protected mice and exhibited a stable Treg phenotype characterized by FOXP3 TSDR demethylation. CONCLUSIONS AND CLINICAL RELEVANCE: Helicobacter pylori confers protection against the anaphylaxis associated with ovalbumin and peanut allergy and affects the epigenome of T cells, thereby promoting stable Treg differentiation and functionality. Prophylactic treatment with H. pylori-derived immunomodulators appears to be a promising strategy for food allergy prevention.


Subject(s)
Anaphylaxis/prevention & control , Bacterial Proteins/immunology , Food Hypersensitivity/prevention & control , Helicobacter pylori/immunology , Immunologic Factors/immunology , Allergens/immunology , Anaphylaxis/genetics , Anaphylaxis/immunology , Anaphylaxis/metabolism , Animals , CpG Islands , Cytokines/blood , Cytokines/metabolism , DNA Methylation , Disease Models, Animal , Food Hypersensitivity/genetics , Food Hypersensitivity/immunology , Food Hypersensitivity/metabolism , Immunoglobulin E/immunology , Male , Mice , Peanut Hypersensitivity/genetics , Peanut Hypersensitivity/immunology , Peanut Hypersensitivity/metabolism , Peanut Hypersensitivity/prevention & control , Spleen/cytology , Spleen/immunology , T-Lymphocytes, Regulatory/immunology , T-Lymphocytes, Regulatory/metabolism
3.
Nanoscale ; 9(19): 6436-6447, 2017 May 18.
Article in English | MEDLINE | ID: mdl-28463371

ABSTRACT

The limited performance of platinum-based electrocatalysts for glucose electrooxidation is a major concern for glucose fuel cells, since glucose electrooxidation is characterized by slow reaction kinetics and low diffusion coefficient. Here, the presented graphene-supported platinum-based hierarchical nanostructures attain highly enhanced electrocatalytic activity towards glucose oxidation. Platinum nanoparticles electrodeposited on graphene support retain mechanical stability and act as junctions allowing a reliable, smooth and dense growth of platinum nanowires with extremely small diameters (>10 nm) on graphene. The electrode's surface roughness was increased by factors up to 4000 to the geometrical surface area enabling maximized exploitation of the electrocatalytic activity of platinum and efficient electron transfer between nanowires and the substrate. The unique three-dimensional geometry of these hierarchical nanostructures has a significant impact on their catalytic performance offering short diffusional paths for slow glucose species, thus, mass transport limitations are optimized leading to lower polarization losses. This was examined by galvanostatic measurements of the operation as anodes in glucose half-cells under conditions corresponding to implantable glucose fuel cells. The presented hierarchical nanostructures show remarkably enhanced catalytic performance for glucose electrooxidation, i.e. a negatively shifted open circuit potential of -580 mV vs. Ag/AgCl, hence, representing appropriate electrocatalysts for use as anodes in glucose fuel cells. In combination with a non-metal N-doped graphene cathode, a cell potential of 0.65 V was achieved at a galvanostatic load of 17.5 µA cm-2 which noticeably surpasses the performance of state of the art catalysts for the aforementioned operation conditions.

4.
Sci Rep ; 7: 42174, 2017 02 09.
Article in English | MEDLINE | ID: mdl-28181530

ABSTRACT

In this paper, we demonstrate and thoroughly analyze the activation volumetric properties of selected liquid crystals in the nematic and crystalline E phases in comparison with those reported for glass-forming liquids. In the analysis, we have employed and evaluated two entropic models (based on either total or configurational entropies) to describe the longitudinal relaxation times of the liquid crystals in the density scaling regime. In this study, we have also exploited two equations of state: volumetric and activation volumetric ones. As a result, we have established that the activation volumetric properties of the selected liquid crystals are quite opposite to such typical properties of glass-forming materials, i.e., the activation volume decreases and the isothermal bulk modulus increases when a liquid crystal is isothermally compressed. Using the model based on the configurational entropy, we suggest that the increasing pressure dependences of the activation volume in isothermal conditions and the negative curvature of the pressure dependences of isothermal longitudinal relaxation times can be related to the formation of antiparallel doublets in the examined liquid crystals. A similar pressure effect on relaxation dynamics may be also observed for other material groups in case of systems, the molecules of which form some supramolecular structures.

5.
Methods Enzymol ; 584: 229-253, 2017.
Article in English | MEDLINE | ID: mdl-28065265

ABSTRACT

Intramembrane proteases are an ancient and diverse group of multispanning membrane proteins that cleave transmembrane substrates inside the membrane to effect a wide range of biological processes. As proteases, a clear understanding of their function requires kinetic dissection of their catalytic mechanism, but this is difficult to achieve for membrane proteins. Kinetic measurements in detergent systems are complicated by micelle fusion/exchange, which introduces an additional kinetic step and imposes system-specific behaviors (e.g., cooperativity). Conversely, kinetic analysis in proteoliposomes is hindered by premature substrate cleavage during coreconstitution, and lack of methods to quantify proteolysis in membranes in real time. In this chapter, we describe a method for the real-time kinetic analysis of intramembrane proteolysis in model liposomes. Our assay is inducible, because the enzyme is held inactive by low pH during reconstitution, and fluorogenic, since fluorescence emission from the substrate is quenched near lipids but restored upon proteolytic release from the membrane. The precise measurement of initial reaction velocities continuously in real time facilitates accurate steady-state kinetic analysis of intramembrane proteolysis and its inhibition inside the membrane environment. Using real data we describe a step-by-step strategy to implement this assay for essentially any intramembrane protease.


Subject(s)
Amyloid Precursor Protein Secretases/chemistry , Molecular Biology/methods , Peptide Hydrolases/chemistry , Proteolysis , Amyloid Precursor Protein Secretases/isolation & purification , Detergents/chemistry , Humans , Kinetics , Membrane Lipids/chemistry , Peptide Hydrolases/isolation & purification , Proteolipids/chemistry , Substrate Specificity
6.
Orv Hetil ; 157(46): 1819-1829, 2016 Nov.
Article in Hungarian | MEDLINE | ID: mdl-27817226

ABSTRACT

For decades, developing hematopoietic cells have been strictly compartmentalized into a small population of multipotent self-renewing hematopoietic stem cells, multipotent hematopoietic progenitor cells that are undergoing commitment to myeloid or lymphoid fates, and unipotent precursor cells that mature towards peripheral blood and immune cells. Recent studies, however, have provided a battery of findings that cannot be explained by this "classical" hierarchical model for the architecture of hematopoiesis. It is emerging that heterogeneous hematopoietic stem cell populations in the bone marrow coexist, each with distinct, preprogrammed differentiation and proliferation behaviors. Three subsets can be distinguished among them: myeloid-biased (α), balanced (ß), and lymphoid-biased (γ/δ) hematopoietic stem cells. The ratio of these hematopoietic stem cell subsets is developmentally regulated in the foetal liver and hematopoietic stem cells adult bone marrow, and coordinately gives rise to hematopoiesis. Beta- and γ/δ-hematopoietic stem cells are found predominantly early in the life of an organism, whereas α-hematopoietic stem cells accumulate in aged mice and humans. In addition, new sophisticated genetic experiments in mice have identified a major role of long-lived, committed progenitor cells downstream from hematopoietic stem cells as drivers of normal adult hematopoiesis, and revealed that post-transplantation hematopoiesis differs qualitatively and quantitatively from normal steady-state hematopoiesis. These findings have important implications for understanding in situ the regulation of haematopoiesis in health and disease. Orv. Hetil., 2016, 157(46), 1819-1829.


Subject(s)
Hematopoiesis , Hematopoietic Stem Cells/cytology , Hematopoietic Stem Cells/metabolism , Myeloid-Lymphoid Leukemia Protein/metabolism , Cell Differentiation/physiology , Humans , Multipotent Stem Cells/cytology
7.
Sci Rep ; 6: 24032, 2016 Apr 06.
Article in English | MEDLINE | ID: mdl-27049119

ABSTRACT

Proteasome-catalyzed peptide splicing represents an additional catalytic activity of proteasomes contributing to the pool of MHC-class I-presented epitopes. We here biochemically and functionally characterized a new melanoma gp100 derived spliced epitope. We demonstrate that the gp100(mel)47-52/40-42 antigenic peptide is generated in vitro and in cellulo by a not yet described proteasomal condensation reaction. gp100(mel)47-52/40-42 generation is enhanced in the presence of the ß5i/LMP7 proteasome-subunit and elicits a peptide-specific CD8(+) T cell response. Importantly, we demonstrate that different gp100(mel)-derived spliced epitopes are generated and presented to CD8(+) T cells with efficacies comparable to non-spliced canonical tumor epitopes and that gp100(mel)-derived spliced epitopes trigger activation of CD8(+) T cells found in peripheral blood of half of the melanoma patients tested. Our data suggest that both transpeptidation and condensation reactions contribute to the frequent generation of spliced epitopes also in vivo and that their immune relevance may be comparable to non-spliced epitopes.


Subject(s)
Alternative Splicing , Epitopes/chemistry , Proteasome Endopeptidase Complex/metabolism , gp100 Melanoma Antigen/chemistry , Algorithms , Antigen Presentation/immunology , Antigens/chemistry , Antigens, Neoplasm/immunology , CD8-Positive T-Lymphocytes/cytology , Case-Control Studies , Catalysis , Cell Line, Tumor , Epitopes, T-Lymphocyte/immunology , HeLa Cells , Humans , Interferon-gamma/metabolism , Melanocytes/cytology , Melanoma/metabolism , Peptides/chemistry , Probability , Proteasome Endopeptidase Complex/chemistry
8.
Eur J Pharm Biopharm ; 103: 159-166, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27049970

ABSTRACT

The aim of this study was the development of a liposomal formulation containing specific tetraether lipids for the oral administration of the investigational hepatitis B peptide drug Myrcludex B. For this purpose, tetraether lipids were extracted from the extremophilic archaeon Sulfolobus acidocaldarius and purified in order to obtain the desired glycerylcaldityltetraether lipids (GCTE). Myrcludex B was synthesized by solid-phase synthesis and incorporated into liposomes containing 5mol% of GCTE. These liposomes showed a size, polydispersity index and zeta potential comparable to the standard liposomes. Cryo-EM micrographs of both liposomal formulations displayed low lamellarity, the prerequisite for high drug loading capacity. Long term storage of the GCTE-liposomes was achieved by freeze-drying using 100-500mM sucrose or trehalose as lyoprotectors. The lyophilized product showed high stability with a recovery rate of 82.7±1.6% of intact Myrcludex B observed after storage for 3months at -20°C as compared to a recovery rate of 83.3±1.3% directly after the freeze-drying process. In vivo, the GCTE-liposomal formulation led to substantial enhancement of the liver uptake of iodine-131-labeled Myrcludex B in Wistar rats. 3h after oral application, approximately 7% of the initial dose (corresponding to a 3.5-fold increase compared to the free peptide) could be detected in the liver. In summary, the GCTE-liposomes enabled efficient oral administration of Myrcludex B and provided long term storage by freeze-drying.


Subject(s)
Antiviral Agents/therapeutic use , Hepatitis B/drug therapy , Lipopeptides/therapeutic use , Liposomes , Administration, Oral , Animals , Drug Compounding , Male , Rats , Rats, Wistar
9.
J Seismol ; 20(2): 511-534, 2016.
Article in English | MEDLINE | ID: mdl-28190965

ABSTRACT

The study focuses on the spatial organization of seismicity and the relation between fracture pattern and earthquakes in the Friuli (north-eastern Italy) and western Slovenia seismic regions. The structural setting is characterized by a complex structure resulting from the superposition of several tectonic phases that generated NW-SE trending Dinaric faults and about E-W trending Alpine faults. The upper crust is characterized by lithological and mechanical heterogeneities. The fractal analysis shows that, in general, the seismicity only partially fills a plane. Only in a few cases, the earthquakes distribute on planar structures. The orientation of planes that fit through the hypocentres shows a different disposition at the two depth intervals analysed. The shallower interval (0-10 km) is characterized by planes with highly variable orientations. The spatial seismicity is investigated in the context of a general damage model, represented by the crack density distribution. The results evidence that the seismicity appears mostly located along sharp transition areas from low crack density to higher crack density, i.e., from zones of low damage to zones of intermediate damage. These zones are characterized by high heterogeneity due to the superposition of different tectonic phases and by the maximum interference between Dinaric and Alpine domains. The orientation of the planes fitting the seismicity at 10-20-km depth appears less dispersed, coinciding with the trend of Dinaric sub-vertical faults in the northern and eastern parts of the study area, and with Alpine low-angle faults in the western and southern parts.

10.
Orv Hetil ; 156(42): 1683-94, 2015 Oct 18.
Article in Hungarian | MEDLINE | ID: mdl-26551308

ABSTRACT

The neural crest is a transient, multipotent, migratory cell population that is unique to vertebrate embryos and gives rise to many derivatives, ranging from the neuronal and glial components of the peripheral nervous system to the ectomesenchymal derivatives of the craniofacial area and pigment cells in the skin. Intriguingly, the neural crest derived stem cells are not only present in the embryonic neural crest, but also in their target tissues in the fetus and adult. These postmigratory stem cells, at least partially, resemble their multipotency. Moreover, fully differentiated neural crest-derived cells such as Schwann cells and melanocytes are able to dedifferentiate into stem-like progenitors. Here the authors review current understanding of this unique plasticity and its potential application in stem cell biology as well as in regenerative medicine.


Subject(s)
Cell Dedifferentiation , Cell Movement , Multipotent Stem Cells , Neural Crest/cytology , Pluripotent Stem Cells , Animals , Cell Differentiation , Humans , Melanocytes/physiology , Multipotent Stem Cells/physiology , Pluripotent Stem Cells/physiology , Schwann Cells/physiology , Stem Cells/physiology
11.
Bratisl Lek Listy ; 116(12): 707-13, 2015.
Article in English | MEDLINE | ID: mdl-26924138

ABSTRACT

BACKGROUND: Triggering receptors expressed on myelocytes (TREM) belong to new molecules with a great role in innate immune system and inflammation. While TREM-1 is known for its pro-inflammatory activity, the TREM-2 has anti-inflammatory activity and has a great impact on granuloma formation, typical sign of sarcoidosis and other granulomatous diseases. METHODS: In our study, we compared the TREM-1 and TREM-2 receptor expressions on the myeloid cell surfaces in bronchoalveolar lavage fluid in patients with pulmonary sarcoidosis (PS), other interstitial lung diseases (ILD), asthma bronchiale (AB), pneumonia, lung cancers, and Quantiferon TB positive patients. RESULTS: We found increased number of all TREM variables (total number, percentage, and mean fluorescence intensity /MFI/) of TREM-1 and TREM-2 positive cells in PS and AB patients compared to the control group of patients with other ILD. In patients with pneumonia, only expression of TREM-1 receptor was increased. In ILD, AB and group of pneumonia patients, the increase of TREM-1 and TREM-2 expression was associated with an increased number of eosinophils. CONCLUSION: TREM-1 and TREM-2 tests are good diagnostic tests for sarcoidosis. Their sensitivity and specificity are comparable with the currently common using test, that of CD4/CD8 ratio. The combination of both tests (CD4/CD8 ratio test together with TREM-1 and TREM-2 tests) resulted in an increased sensitivity and specificity (Tab. 7, Fig. 1, Ref. 28).

12.
J Chem Phys ; 140(7): 074502, 2014 Feb 21.
Article in English | MEDLINE | ID: mdl-24559352

ABSTRACT

The synthesis, equation of state, phase diagram, and dielectric relaxation properties are reported for a new liquid crystal, 4(')-butyl-4-(2-methylbutoxy)azoxybenzene (4ABO5*), which exhibits a cholesteric phase at ambient temperature. The steepness of the intermolecular potential was characterized from the thermodynamic potential parameter, Γ = 4.3 ± 0.1 and the dynamic scaling exponent, γ = 3.5 ± 0.2. The difference between them is similar to that seen previously for nematic and smectic liquid crystals, with the near equivalence of Γ and γ consistent with the near constancy of the relaxation time of 4ABO5* at the cholesteric to isotropic phase transition (i.e., the clearing line). Thus, chirality does not cause deviations from the general relationship between thermodynamics and dynamics in the ordered phase of liquid crystals. The ionic conductivity of 4ABO5* shows strong coupling to the reorientational dynamics.

13.
Nervenarzt ; 84(1): 38-44, 2013 Jan.
Article in German | MEDLINE | ID: mdl-22476441

ABSTRACT

BACKGROUND: The aim of the present study was to develop a questionnaire to assess the perception and evaluation of admission to a psychiatric hospital from a patient's perspective (QAE-P). MATERIAL AND METHODS: Based on existing literature and a preparatory pilot study, a questionnaire consisting of 126 items was developed, and 708 inpatients based in 6 psychiatry and psychotherapy clinics were asked to answer the items. The resulting data were split into two data sets. In the first subset, exploratory factor analysis was used to help determine the number of scales and provide the basis for item reduction. The resulting questionnaire was validated by means of confirmatory factor analyses (CFA) in the second data subset. RESULTS: The resulting questionnaire comprises 33 items in 7 scales, which assess: (1) helpful, positive relations with staff members; (2) offering of medical explanations to patients and their involvement in treatment planning; (3) evaluation of rooms and clinical environment; (4) dissatisfaction with doctors and staff members; (5) evaluation of handling of ward rules by staff; (6) perception of ward atmosphere; and (7) negative perception of other inpatients. The plausibility of this factorial structure was supported by the results of the CFA. CONCLUSIONS: The QAE-P is a short and feasible questionnaire that meets the criteria of classic test theory and assesses different dimensions of the patient's experience of admission to a psychiatric hospital.


Subject(s)
Commitment of Mentally Ill , Hospitals, Psychiatric , Mental Disorders/psychology , Mental Disorders/rehabilitation , Patient Admission , Patient Satisfaction , Psychiatric Department, Hospital , Surveys and Questionnaires , Adult , Aged , Coercion , Cooperative Behavior , Factor Analysis, Statistical , Female , Germany , Humans , Interdisciplinary Communication , Male , Memory Disorders/diagnosis , Memory Disorders/psychology , Middle Aged , Mood Disorders/psychology , Mood Disorders/rehabilitation , Pilot Projects , Professional-Patient Relations , Psychometrics/statistics & numerical data , Psychotic Disorders/psychology , Psychotic Disorders/rehabilitation , Reproducibility of Results , Social Environment , Social Perception , Substance-Related Disorders/psychology , Substance-Related Disorders/rehabilitation
14.
Nervenarzt ; 84(1): 45-54, 2013 Jan.
Article in German | MEDLINE | ID: mdl-22476513

ABSTRACT

BACKGROUND: The purpose of this study was to investigate associations of patient's scores in the newly constructed questionnaire on patients' psychiatric admission experiences (QAE-P) and individual, institutional, and situational factors. PATIENTS AND METHODS: Data of 708 patients and 6 participating hospitals were analyzed. Patient characteristics between clinics were compared and univariate as well as multivariate analyses were applied to examine associations of QAE-P total score and individual as well as institutional variables (t tests, univariate and multivariate analyses of variance, correlation analyses, and effect sizes of significant associations). RESULTS: There was little variance of patient characteristics between hospitals. Multiple univariate associations with small to medium effect sizes were found between total QAE-P scores and demographic and clinical variables of the patients, institutional variables, and (non-independent) situational views of the patients. After multivariate analyses were applied, these associations remained significant for gender, age, diagnosis, the personal decision to be admitted, and for previous planning of admission with the outpatient doctor. The hospital variables shown to be associated with total QAE-P scores were open versus closed ward, disorder-specific organization of the ward, and the number of other patients being treated under the German Mental Health Act. CONCLUSION: Principally the QAE-P seems to be a suitable instrument of quality management. A number of factors were identified that show associations with the subjective evaluation of admission as reported by the patients. Some of these variables are within the control of the clinical management.


Subject(s)
Commitment of Mentally Ill , Hospitals, Psychiatric , Mental Disorders/psychology , Mental Disorders/rehabilitation , Patient Admission , Patient Satisfaction , Surveys and Questionnaires , Adult , Factor Analysis, Statistical , Female , Germany , Humans , Male , Middle Aged , Pilot Projects , Professional-Patient Relations , Psychometrics/statistics & numerical data , Reproducibility of Results , Social Environment , Social Perception
15.
Orv Hetil ; 153(6): 214-21, 2012 Feb 12.
Article in Hungarian | MEDLINE | ID: mdl-22296925

ABSTRACT

Analysis of genomic sequences has clearly shown that the genomic differences among species do not explain the diversity of life. The genetic code itself serves as only a part of the dynamic complexity that results in the temporal and spatial changes in cell phenotypes during development. It has been concluded that the phenotype of a cell and of the organism as a whole is more influenced by environmentally-induced changes in gene activity than had been previously thought. The emerging field of epigenetics focuses on molecular marks on chromatin; called the epigenome, which serve as transmitters between the genome and the environment. These changes not only persist through multiple cell division cycles, but may also endure for multiple generations. Irregular alterations of the epigenome; called epimutations, may have a decisive role in the etiology of human pathologies such as malignancies and other complex human diseases. Epigenetics can provide the missing link between genetics, disease and the environment. Therefore, this field may have an increasing impact on future drug design and serve as a basis for new therapeutic/preventative approaches.


Subject(s)
Epigenesis, Genetic , Epigenomics/trends , Gene-Environment Interaction , Genetic Therapy/trends , Molecular Biology/trends , Mutation , Neoplasms/genetics , Chromatin/genetics , DNA Methylation/genetics , Genetic Therapy/methods , Genome/genetics , Histones/genetics , Humans , Mutation/genetics , Neoplasms/therapy , Phenotype , RNA, Untranslated
16.
J Phys Chem B ; 115(20): 6437-44, 2011 May 26.
Article in English | MEDLINE | ID: mdl-21539380

ABSTRACT

From measurements of the specific volume as a function of temperature and pressure, the phase diagram for the liquid crystal forming isopentylcyanobiphenyl (5*CB) was determined. There are a number of phases (isotropic liquid, glass, cholesteric, and crystalline), and we show that the phase boundaries differ from previous reports, reflecting the slow crystallization kinetics of the system. Using dielectric spectroscopy at ambient and elevated pressure, we identify the relaxation processes in the isotropic and cholesteric phases. From application of density scaling to the dynamics, we obtain scaling exponents, which were found to vary with the type of motion. Moreover, unlike previous results for many other liquid crystals, the scaling exponent for the isotropic state differs from the thermodynamic potential parameter, and hence the relaxation time along the clearing line varies significantly with pressure. The distinctive properties of 5*CB reflect the very different volume dependences of the thermodynamics and the dynamics.

18.
J Phys Chem B ; 113(48): 15783-94, 2009 Dec 03.
Article in English | MEDLINE | ID: mdl-19852505

ABSTRACT

Orientational order properties of two fluorinated liquid crystals containing the 1,3,2-dioxaborinane ring have been investigated by means of optical, dielectric, and (13)C and (19)F NMR spectroscopies. The optical birefringence and dielectric anisotropy values determined in the mesomorphic phases were analyzed in terms of well-established theoretical models to obtain the order parameters relative to the principal axis of the polarizability tensor and molecular dipole moment, respectively. A large set of data, including (13)C and (19)F chemical shift anisotropies and (13)C-(19)F and (1)H-(19)F couplings relative to nuclei on the aromatic rings, was acquired in the NMR experiments and analyzed to determine local order parameters (principal order parameter and biaxiality) for different rigid fragments of the mesogen aromatic core using advanced DFT methods for the calculation of geometrical parameters and chemical shift tensors. A critical analysis of the dependence of the order parameters on the data set employed and on the theoretical assumptions and approximations has also been performed. The orientational order parameters obtained using the different techniques are compared and discussed in relation to the reference frame associated with the anisotropic properties monitored.

19.
Eur J Med Res ; 14(4): 147-56, 2009 Apr 16.
Article in English | MEDLINE | ID: mdl-19380287

ABSTRACT

OBJECTIVE: LIGHT (TNFSF 14) belongs to the tumor necrosis factor superfamily and is expressed by activated T cells as well as various types of antigen presenting cells. LIGHT binds to its cellular receptors TR2 and LTbetaR and has a co-stimulatory role in T cell activation. Here, we compared the relative expression of LIGHT in different immune cells and the biological activity of immune cell-derived LIGHT on endothelial cells. METHODS AND RESULTS: Surface expression of LIGHT and mRNA production by PBMC and isolated T cells (CD4+ or CD8+) significantly increased after stimulation with PMA (Phorbolester-12- Myristat-13-Acetat)+ionomycin. No LIGHT expression on PMA stimulated monocytes or monocytic-like THP-1 cells could be detected; differentiation of monocytes and THP-1 cells into macrophages, however, resulted in up-regulation of LIGHT. Supernatants of stimulated T cells contained higher concentrations of soluble LIGHT than macrophage supernatants normalized to cell numbers; release of soluble LIGHT was found to be dependent on metalloproteinase activity. Size determination of released soluble LIGHT by size exclusion chromatography revealed a molecular mass of approximately 60 kDa, suggesting a trimeric form. Released soluble LIGHT induced expression of proinflammatory antigens ICAM-1, tissue factor and IL-8 in human endothelial cells and caused apoptosis of IFN-g pretreated endothelial cells. Soluble LIGHT was detected at low levels in sera of healthy controls and was significantly enhanced in sera of patients with chronic hepatitis C and rheumatoid arthritis (24.93+/-9.41 vs. 129.53+/-49.14 and 172.13+/-77.64; p<0.0005). CONCLUSION: These findings suggest that among immune cells activated T lymphocytes are the main source of soluble LIGHT with released amounts of soluble LIGHT markedly higher compared to platelets. Immune cell-derived membrane-bound and soluble trimeric LIGHT is biologically active, inducing proinflammatory changes in endothelial cells. Enhanced plasma levels of soluble LIGHT in patients with chronic infections suggest a role of LIGHT in systemic inflammatory activation.


Subject(s)
Endothelium, Vascular/metabolism , Leukocytes, Mononuclear/immunology , Macrophages/immunology , T-Lymphocytes/immunology , Tumor Necrosis Factor Ligand Superfamily Member 14/metabolism , Adolescent , Adult , Aged , Arthritis, Rheumatoid/blood , Cell Differentiation , Cells, Cultured , Drug Combinations , Endothelium, Vascular/drug effects , Enzyme-Linked Immunosorbent Assay , Female , Gene Expression/drug effects , Hepatitis C, Chronic/blood , Humans , Intercellular Adhesion Molecule-1/metabolism , Interleukin-8/metabolism , Ionomycin/pharmacology , Leukocytes, Mononuclear/drug effects , Macrophages/drug effects , Middle Aged , Molecular Weight , RNA, Messenger/metabolism , T-Lymphocytes/drug effects , Tetradecanoylphorbol Acetate/pharmacology , Thromboplastin/metabolism , Tumor Necrosis Factor Ligand Superfamily Member 14/blood , Tumor Necrosis Factor Ligand Superfamily Member 14/genetics , Umbilical Veins/cytology , Up-Regulation , Young Adult
20.
J Phys Chem B ; 112(32): 9663-76, 2008 Aug 14.
Article in English | MEDLINE | ID: mdl-18646816

ABSTRACT

Structural and orientational order properties of 3Cy2CyBF2 and of 5CyCy2BF2 have been investigated by means of (13)C-NMR, optical, and dielectric spectroscopy methods. In the case of NMR, order parameters have been independently obtained from the analysis of either (13)C-(19)F dipolar couplings or (13)C chemical shift anisotropies, both measured from (13)C-{(1)H} NMR static spectra. The assignment of the (13)C resonances has been carried out thanks to the comparison with solution state spectra and DFT calculations, and the relevant geometrical parameters and (13)C chemical shift tensors needed to derive orientational order parameters have been calculated by DFT methods. In the analysis of (13)C-(19)F dipolar couplings, empirical corrections for vibrations and anisotropic scalar couplings have been included. Dielectric measurements have been performed over a broad frequency range for two orientations of the nematic director with respect to the measuring field. At low frequencies (static case) a positive dielectric anisotropy has been determined, which has enabled the calculation of the order parameters according to a well-tested procedure. At high frequencies the dielectric anisotropy changes its sign, a property which can be useful in designing a dual addressing display. The nematic order parameter determined from optical, dielectric, and NMR methods have been compared: their trends with temperature are very similar, apart from some slight shifts, and were analyzed by Haller and Chirtoc models. The differences among the results obtained by the four methods have been discussed in detail, also with reference to the assumptions and approximations used in each case, and to the results recently reported for similar fluorinated nematogens. The presence of a non-negligible order biaxiality has been related to the presence of a CH2CH2 bridging group, linking one cyclohexylic unit with either the other cyclohexyl or the phenyl ring.

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