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1.
Gastroenterol Nurs ; 46(2): 107-117, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36882915

RESUMO

Patients with decompensated liver cirrhosis constitute a growing and vulnerable patient group with a particular need for easy outpatient access and close follow-up. By establishing a nurse-led clinic, we aimed to counter this need in a patient-centered manner within a multidisciplinary rehabilitating framework. This article presents the organization, staffing, and structure of this initiative as well as the patient population demographics and characteristics. Furthermore, patient satisfaction within the clinic was explored. Two complementary substudies are presented: a descriptive, registry-based journal audit, presenting data from the clinic's first years, 2017-2019, and a cross-sectional, descriptive survey, exploring patient satisfaction 2 years later. Different visit types with predefined content constitute an operable structure suitable for meeting patients' current needs. An increase in both the number of patients and visits from the first to second years indicates an existing need for nurse-led support. Data not only support the well-known characteristics of patients with cirrhosis but also add to a broader perspective with more nuances for this patient population. The survey shows an overall high score on satisfaction but also points out areas for improvement. The nurse-led clinic provides both structure and knowledge to facilitate patient-centered treatment and care for those suffering from liver cirrhosis.


Assuntos
Pacientes Ambulatoriais , Satisfação do Paciente , Humanos , Estudos Transversais , Papel do Profissional de Enfermagem , Instituições de Assistência Ambulatorial , Recursos Humanos
2.
J Extracell Vesicles ; 9(1): 1764213, 2020 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-32944168

RESUMO

Major efforts are made to characterize the presence of microRNA (miRNA) and messenger RNA in blood plasma to discover novel disease-associated biomarkers. MiRNAs in plasma are associated to several types of macromolecular structures, including extracellular vesicles (EV), lipoprotein particles (LPP) and ribonucleoprotein particles (RNP). RNAs in these complexes are recovered at variable efficiency by commonly used EV- and RNA isolation methods, which causes biases and inconsistencies in miRNA quantitation. Besides miRNAs, various other non-coding RNA species are contained in EV and present within the pool of plasma extracellular RNA. Members of the Y-RNA family have been detected in EV from various cell types and are among the most abundant non-coding RNA types in plasma. We previously showed that shuttling of full-length Y-RNA into EV released by immune cells is modulated by microbial stimulation. This indicated that Y-RNAs could contribute to the functional properties of EV in immune cell communication and that EV-associated Y-RNAs could have biomarker potential in immune-related diseases. Here, we investigated which macromolecular structures in plasma contain full length Y-RNA and whether the levels of three Y-RNA subtypes in plasma (Y1, Y3 and Y4) change during systemic inflammation. Our data indicate that the majority of full length Y-RNA in plasma is stably associated to EV. Moreover, we discovered that EV from different blood-related cell types contain cell-type-specific Y-RNA subtype ratios. Using a human model for systemic inflammation, we show that the neutrophil-specific Y4/Y3 ratios and PBMC-specific Y3/Y1 ratios were significantly altered after induction of inflammation. The plasma Y-RNA ratios strongly correlated with the number and type of immune cells during systemic inflammation. Cell-type-specific "Y-RNA signatures" in plasma EV can be determined without prior enrichment for EV, and may be further explored as simple and fast test for diagnosis of inflammatory responses or other immune-related diseases.

3.
J Extracell Vesicles ; 9(1): 1798606, 2020 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-32944186

RESUMO

Dendritic cells (DC) have the unique capacity to activate naïve T cells by presenting T cell receptor specific peptides from exogenously acquired antigens bound to Major Histocompatibility Complex (MHC) molecules. MHC molecules are displayed on the DC plasma membrane as well as on extracellular vesicles (EV) that are released by DC, and both have antigen-presenting capacities. However, the physiological role of antigen presentation by EV is still unclear. We here demonstrate that the release of small EV by activated DC is strongly stimulated by phagocytic events. We show that, concomitant with the enhanced release of EV, a significant proportion of phagocytosed bacteria was expulsed back into the medium. High-resolution fluorescence microscopic images revealed that bacteria in phagosomes were surrounded by EV marker-proteins. Moreover, expulsed bacteria were often found associated with clustered HLA II and CD63. Together, these observations suggest that exosomes may be formed by the inward budding into phagosomes, whereupon they are secreted together with the phagosomal content. These findings may have important implications for selective loading of peptides derived from phagocytosed pathogens onto exosome associated HLA molecules, and have important implications for vaccine design.

4.
Eur J Immunol ; 50(8): 1209-1219, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32198923

RESUMO

Ankylosing spondylitis (AS) is associated with autoantibody production to class II MHC-associated invariant chain peptide, CD74/CLIP. In this study, we considered that anti-CD74/CLIP autoantibodies present in sera from AS might recognize CD74 degradation products that accumulate upon deficiency of the enzyme signal peptide peptidase-like 2A (SPPL2a). We analyzed monocytes from healthy controls (n = 42), psoriatic arthritis (n = 25), rheumatoid arthritis (n = 16), and AS patients (n = 15) for SPPL2a enzyme activity and complemented the experiments using SPPL2a-sufficient and -deficient THP-1 cells. We found defects in SPPL2a function and CD74 processing in a subset of AS patients, which culminated in CD74 and HLA class II display at the cell surface. These findings were verified in SPPL2a-deficient THP-1 cells, which showed expedited expression of MHC class II, total CD74 and CD74 N-terminal degradation products at the plasma membrane upon receipt of an inflammatory trigger. Furthermore, we observed that IgG anti-CD74/CLIP autoantibodies recognize CD74 N-terminal degradation products that accumulate upon SPPL2a defect. In conclusion, reduced activity of SPPL2a protease in monocytes from AS predisposes to endosomal accumulation of CD74 and CD74 N-terminal fragments, which, upon IFN-γ-exposure, is deposited at the plasma membrane and can be recognized by anti-CD74/CLIP autoantibodies.


Assuntos
Antígenos de Diferenciação de Linfócitos B/imunologia , Ácido Aspártico Endopeptidases/fisiologia , Autoanticorpos/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Proteólise , Espondilite Anquilosante/imunologia , Adulto , Idoso , Antígenos de Diferenciação de Linfócitos B/metabolismo , Feminino , Antígenos HLA-DR/análise , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Imunoglobulina G/imunologia , Interferon gama/farmacologia , Masculino , Pessoa de Meia-Idade , Células THP-1
5.
Pharmacol Res Perspect ; 7(3): e00480, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31164987

RESUMO

N-methyl-d-aspartate receptors (NMDAR) are widely expressed in the brain. GluN2B subunit-containing NMDARs has recently attracted significant attention as potential pharmacological targets, with emphasis on the functional properties of allosteric antagonists. We used primary cultures from chicken embryo forebrain (E10), expressing native GluN2B-containing NMDA receptors as a novel model system. Comparing the inhibition of calcium influx by well-known GluN2B subunit-specific allosteric antagonists, the following rank order of potency was found: EVT-101 (EC 50 22 ± 8 nmol/L) > Ro 25-6981 (EC 50 60 ± 30 nmol/L) > ifenprodil (EC 50 100 ± 40 nmol/L) > eliprodil (EC 50 1300 ± 700 nmol/L), similar to previous observations in rat cortical cultures and cell lines overexpressing chimeric receptors. The less explored Ro 04-5595 had an EC 50 of 186 ± 32 nmol/L. Venturing to explain the differences in potency, binding properties were further studied by in silico docking and molecular dynamics simulations using x-ray crystal structures of GluN1/GluN2B amino terminal domain. We found that Ro 04-5595 was predicted to bind the recently discovered EVT-101 binding site, not the ifenprodil-binding site. The EVT-101 binding pocket appears to accommodate more structurally different ligands than the ifenprodil-binding site, and contains residues essential in ligand interactions necessary for calcium influx inhibition. For the ifenprodil site, the less effective antagonist (eliprodil) fails to interact with key residues, while in the EVT-101 pocket, difference in potency might be explained by differences in ligand-receptor interaction patterns.


Assuntos
Imidazóis/administração & dosagem , Piperidinas/administração & dosagem , Prosencéfalo/citologia , Piridazinas/administração & dosagem , Receptores de N-Metil-D-Aspartato/química , Receptores de N-Metil-D-Aspartato/metabolismo , Animais , Sítios de Ligação , Linhagem Celular , Células Cultivadas , Embrião de Galinha , Células HEK293 , Humanos , Imidazóis/química , Imidazóis/farmacologia , Modelos Moleculares , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Fenóis/administração & dosagem , Fenóis/química , Fenóis/farmacologia , Piperidinas/química , Piperidinas/farmacologia , Prosencéfalo/efeitos dos fármacos , Prosencéfalo/metabolismo , Domínios Proteicos , Piridazinas/química , Piridazinas/farmacologia , Ratos
6.
Front Immunol ; 10: 448, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30915085

RESUMO

Extracellular vesicles (EV) that are released by immune cells are studied intensively for their functions in immune regulation and are scrutinized for their potential in human immunotherapy, for example against cancer. In our search for signals that stimulate the release of functional EV by dendritic cells we observed that LPS-activated human monocyte-derived dendritic cells (moDC) changed their morphological characteristics upon contact with non-cognate activated bystander T-cells, while non-activated bystander T-cells had no effect. Exposure to activated bystander T-cells also stimulated the release of EV-associated proteins by moDC, particularly CD63, and ICAM-1, although the extent of stimulation varied between individual donors. Stimulation of moDC with activated bystander T-cells also increased the release of EV-associated miR155, which is a known central modulator of T-cell responses. Functionally, we observed that EV from moDC that were licensed by activated bystander T-cells exhibited a capacity for antigen-specific T-cell activation. Taken together, these results suggest that non-cognatei interactions between DC and bystander T-cells modulates third party antigen-specific T-cell responses via EV.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/imunologia , Vesículas Extracelulares/imunologia , Ativação Linfocitária/imunologia , Apresentação de Antígeno/imunologia , Células Cultivadas , Microambiente Celular/imunologia , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Lipopolissacarídeos , MicroRNAs/genética , Tetraspanina 30/metabolismo
7.
Annu Rev Immunol ; 36: 435-459, 2018 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-29400984

RESUMO

The initiation and maintenance of adaptive immunity require multifaceted modes of communication between different types of immune cells, including direct intercellular contact, secreted soluble signaling molecules, and extracellular vesicles (EVs). EVs can be formed as microvesicles directly pinched off from the plasma membrane or as exosomes secreted by multivesicular endosomes. Membrane receptors guide EVs to specific target cells, allowing directional transfer of specific and complex signaling cues. EVs are released by most, if not all, immune cells. Depending on the type and status of their originating cell, EVs may facilitate the initiation, expansion, maintenance, or silencing of adaptive immune responses. This review focusses on EVs from professional antigen-presenting cells, their demonstrated and speculated roles, and their potential for cancer immunotherapy.


Assuntos
Apresentação de Antígeno/imunologia , Células Apresentadoras de Antígenos/imunologia , Células Apresentadoras de Antígenos/metabolismo , Vesículas Extracelulares/metabolismo , Animais , Linfócitos B/imunologia , Linfócitos B/metabolismo , Transporte Biológico , Micropartículas Derivadas de Células/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Células Epiteliais/metabolismo , Exossomos/metabolismo , Antígenos de Histocompatibilidade/genética , Antígenos de Histocompatibilidade/imunologia , Humanos , Tolerância Imunológica , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo
8.
PLoS Pathog ; 12(4): e1005550, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27077376

RESUMO

Cell-mediated immunity plays a key role in host control of viral infection. This is exemplified by life-threatening reactivations of e.g. herpesviruses in individuals with impaired T-cell and/or iNKT cell responses. To allow lifelong persistence and virus production in the face of primed immunity, herpesviruses exploit immune evasion strategies. These include a reduction in viral antigen expression during latency and a number of escape mechanisms that target antigen presentation pathways. Given the plethora of foreign antigens expressed in virus-producing cells, herpesviruses are conceivably most vulnerable to elimination by cell-mediated immunity during the replicative phase of infection. Here, we show that a prototypic herpesvirus, Epstein-Barr virus (EBV), encodes a novel, broadly acting immunoevasin, gp150, that is expressed during the late phase of viral replication. In particular, EBV gp150 inhibits antigen presentation by HLA class I, HLA class II, and the non-classical, lipid-presenting CD1d molecules. The mechanism of gp150-mediated T-cell escape does not depend on degradation of the antigen-presenting molecules nor does it require gp150's cytoplasmic tail. Through its abundant glycosylation, gp150 creates a shield that impedes surface presentation of antigen. This is an unprecedented immune evasion mechanism for herpesviruses. In view of its likely broader target range, gp150 could additionally have an impact beyond escape of T cell activation. Importantly, B cells infected with a gp150-null mutant EBV displayed rescued levels of surface antigen presentation by HLA class I, HLA class II, and CD1d, supporting an important role for iNKT cells next to classical T cells in fighting EBV infection. At the same time, our results indicate that EBV gp150 prolongs the timespan for producing viral offspring at the most vulnerable stage of the viral life cycle.


Assuntos
Apresentação de Antígeno/imunologia , Infecções por Vírus Epstein-Barr/imunologia , Evasão da Resposta Imune/imunologia , Ativação Linfocitária/imunologia , Glicoproteínas de Membrana/imunologia , Proteínas Virais/imunologia , Western Blotting , Citometria de Fluxo , Herpesvirus Humano 4/imunologia , Humanos , Microscopia Confocal , Linfócitos T/imunologia , Transdução Genética
9.
Mol Cytogenet ; 8: 61, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26300974

RESUMO

BACKGROUND: Lemon balm (Melissa officinalis L.) is of increasing importance resulting in rising growth area. Improved knowledge on the genome structure, number of chromosomes in connection with the taxonomical structure of balm is indispensable for improved new varieties. RESULTS: A collection of 40 balm accessions (M. officinalis) was characterized by flow cytometry and FISH (18/25S and 5S rDNA) to determine the chromosome number and ploidy level. Three different types were found: diploid genotypes with 2n = 2× = 32 chromosomes; tetraploid 2n = 4× = 64 chromosomes and triploid 2n = 3× = 48 chromosomes. A haploid base number of × = 16 chromosomes is likely. First time described triploid accessions are sterile but cytologically and morphologically stable for many years. Triploids express better winter hardiness and regeneration after harvesting cuts as well as bigger leaves and internodes. CONCLUSIONS: A basic chromosome number of x = 16 is reported for the first time for the species M. officinalis.

10.
Sci Rep ; 5: 10335, 2015 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-26012481

RESUMO

The study of the behavior of sessile droplets on solid substrates is not only associated with common everyday phenomena, such as the coffee stain effect, limescale deposits on our bathroom walls , but also very important in many applications such as purification of pharmaceuticals, de-icing of airplanes, inkjet printing and coating applications. In many of these processes, a phase change happens within the drop because of solvent evaporation, temperature changes or chemical reactions, which consequently lead to liquid to solid transitions in the droplets. Here we show that crystallization patterns of evaporating of water drops containing dissolved salts are different from the stains reported for evaporating colloidal suspensions. This happens because during the solvent evaporation, the salts crystallize and grow during the drying. Our results show that the patterns of the resulting salt crystal stains are mainly governed by wetting properties of the emerging crystal as well as the pathway of nucleation and growth, and are independent of the evaporation rate and thermal conductivity of the substrates.

11.
J Gen Virol ; 96(Pt 4): 858-865, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25502648

RESUMO

During productive infection with Epstein-Barr virus (EBV), a dramatic suppression of cellular protein expression is caused by the viral alkaline exonuclease BGLF5. Among the proteins downregulated by BGLF5 are multiple immune components. Here, we show that shutoff reduces expression of the innate EBV-sensing Toll-like receptor-2 and the lipid antigen-presenting CD1d molecule, thereby identifying these proteins as novel targets of BGLF5. To silence BGLF5 expression in B cells undergoing productive EBV infection, we employed an shRNA approach. Viral replication still occurred in these cells, albeit with reduced late gene expression. Surface levels of a group of proteins, including immunologically relevant molecules such as CD1d and HLA class I and class II, were only partly rescued by depletion of BGLF5, suggesting that additional viral gene products interfere with their expression. Our combined approach thus provides a means to unmask novel EBV (innate) immune evasion strategies that may operate in productively infected B cells.


Assuntos
Linfócitos B/imunologia , Linfócitos B/virologia , Desoxirribonucleases/imunologia , Infecções por Vírus Epstein-Barr/imunologia , Infecções por Vírus Epstein-Barr/virologia , Herpesvirus Humano 4/imunologia , Proteínas Virais/imunologia , Antígenos CD1d/genética , Antígenos CD1d/imunologia , Linhagem Celular , Desoxirribonucleases/genética , Herpesvirus Humano 4/genética , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/imunologia , Humanos , Evasão da Resposta Imune , Imunidade Inata , Receptores Toll-Like/genética , Receptores Toll-Like/imunologia , Proteínas Virais/genética , Replicação Viral/genética , Replicação Viral/imunologia
12.
Protoplasma ; 231(1-2): 89-97, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17370111

RESUMO

Hybrid callus was formed from the successful protoplast fusion between pollen protoplasts of Brassica oleracea var. italica and haploid mesophyll protoplasts of Brassica rapa. The pollen protoplast isolation frequency in broccoli was highly related to the ratio of trinucleate pollens in the male gametophyte population. Large quantities of pollen protoplasts with high vigor could be isolated, and the isolation frequency reached up to 90% in 6.0-7.0 mm long flower buds with about 94.7% trinucleate-stage pollens. Pollen protoplasts could be collected and purified by discontinuous gradient centrifugation. In 1% Na-alginate embedding culture, cell divisions were observed but no further development was found. The haploid mesophyll protoplasts were isolated from in vitro haploid plants of B. rapa. Results strongly showed the variability in culturability of mesophyll protoplasts from different haploid lines. Both pollen protoplasts and haploid mesophyll protoplasts retained a stable round shape in the designed prefusion solution with an osmotic pressure of 0.74 osmol/kg. Polyethylene glycol was used for the protoplast fusion, and 40% polyethylene glycol 4000 enabled the highest fusion frequency of about 20%. Some postfusion protoplasts showed cell divisions up to callus proliferation. Calli were screened by random amplified polymorphic DNA analysis for their hybrid character. Results revealed the existence of the hybrid calli. Some of the hybrid calli grew well with green color and shoot primordia. According to our knowledge, this is the first report about a hybrid formation between two haploid protoplasts. Potential comprehensive applications, as well as problems of this technique, are discussed.


Assuntos
Brassica/classificação , Brassica/citologia , Haploidia , Pólen/citologia , Protoplastos/citologia , Divisão Celular , Fusão Celular , Células Cultivadas , DNA de Plantas , Hibridização Genética , Técnica de Amplificação ao Acaso de DNA Polimórfico
13.
Genome ; 37(4): 550-5, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7958821

RESUMO

A new strategy has been devised and used for the physical localization of genetically mapped restriction fragment length polymorphism (RFLP) clones to barley chromosomes. Morphologically distinct translocation chromosomes from synchronized root-tip meristems were microisolated and their DNA was used as a template for polymerase chain reaction with sequence-specific primers. Four RFLP clones were assigned to cytologically defined segments of chromosome 5. This related approximately one-third of the map length of linkage group 5 to approximately one-fifth of the mitotic metaphase length of chromosome 5. The technique may substantially contribute to the connection of the RFLP-based genetic linkage maps with cytological markers of the barley chromosomes.


Assuntos
Hordeum/genética , Sequência de Bases , Cromossomos , Clonagem Molecular , Primers do DNA/genética , Ligação Genética , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Recombinação Genética , Mapeamento por Restrição , Translocação Genética
14.
Theor Appl Genet ; 89(2-3): 240-8, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24177835

RESUMO

Karyotype analyses based on staining by acetocarmine followed by Giemsa N-banding of somatic metaphase chromosomes of Hordeum vulgare L. were carried out on 61 reciprocal translocations induced by X-irradiation. By means of computer-based karyotype analyses all of the 122 breakpoints could be localized to defined sites or segments distributed over the seven barley chromosomes. The pre-definition of translocations with respect to their rearranged chromosome arms from other studies rendered it possible to define the break positions even in translocations having exchanged segments equal in size and the breakpoints located distally to any Giemsa band or other cytological marker. The breakpoints were found to be non-randomly spaced along the chromosomes and their arms. All breaks but one occurred in interband regions of the chromosomes, and none of the breaks was located directly within a centromere. However, short and long chromosome arms recombined at random. An improved tester set of translocations depicting the known break positions of most distal location is presented.

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