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1.
Z Evid Fortbild Qual Gesundhwes ; 181: 88-97, 2023 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-37217404

RESUMO

BACKGROUND: Despite its important role in the elderly care system, day care in Germany has so far rather little attention paid to it. Keeping their patients' health and self-reliance and facilitating relief and support for family caregivers are central tasks of day care, regulated by law. Nevertheless, there is not only a lack of findings about the working methods and effects of day care, but also of orientation in terms of how to configure high-quality care on a structural, process-related and conceptual level. The aim of the TpQ project ("Weiterentwicklung und Qualitätsverbesserung von Tagespflege in Nordrhein-Westfalen", "further development of and quality improvement in day care facilities in Northrhine-Westphalia") was to close this gap and to offer the institutions a catalogue of impulses that contains current national and international research findings as well as the perspectives of every stakeholder associated with day care. METHOD: In an explorative sequential mixed-method design, we conducted a search for and a synthesis of the literature in the form of a scoping review, qualitative interviews with guests, relatives, non-users, employees and managers of day care, association representatives, nursing scientists and business consultants, a quantitative paper-based survey among guests, relatives, employees and managers of day care and an expert conference for result validation. The sample received study information either directly by mail or through the staff of the recruited adult day care facilities. The survey-area is the federal state of North Rhine-Westphalia. The analysis of the qualitative data was conducted according to the qualitative content analysis and was used for the development of the quantitative surveys. The quantitative data analysis was descriptive. Based on the comparison with literature analysis and qualitative findings, the impulses for the design of day care were finally formulated and validated during an expert workshop. RESULTS: From the literature (N=49) and the interviews (N=85), different expectations and wishes with regard to day care were generated. These included staff and structural requirements as well as concrete ideas of the conceptual orientation of day care. The quantitative survey (N=392) showed considerable agreement with the content-related and organizational requirements of the qualitative survey and allowed us to identify the relevant quality aspects from the point of view of guests, relatives and staff of day care facilities. In summary, 15 dimensions for the design of day care (conception/basic principles, quality management, nursing care, transport/driving service, opening hours, equipment, networking, staff, introduction of new guests, activity offers, health promotion and prevention, promotion of social participation, support of relatives, public work, counseling) were defined as relevant quality areas and explained with 81 impulses. DISCUSSION AND CONCLUSION: Addressing the perspective of users, family caregivers and other persons involved in adult day care reveals complex requirements and opportunities for the design of adult day care. In contrast to existing quality inspection guidelines, the impulses can be used to independently assess adult day care with the goal of contributing to the further development and sharpening of the profile of adult day care.


Assuntos
Cuidadores , Hospital Dia , Adulto , Humanos , Alemanha , Cuidadores/psicologia
2.
Thyroid ; 33(6): 732-742, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37016815

RESUMO

Background: Treatment of Graves' hyperthyroidism (GH) and Graves' orbitopathy (GO) is far from adequate, and hence, new substances that specifically target the autoantigens in GH/GO are warranted. This study determined the preclinical in vitro efficacy of SYD5115, a novel low-molecular-weight compound that inhibits the thyrotropin receptor (TSH-R). Methods: The TSH-R inhibiting capability of SYD5115 was tested through stimulation of wild-type and chimeric TSH-R expressed in Chinese hamster ovary (CHO) cells using two functional (stimulatory and blocking) cell-based TSH-R-Ab bioassays. TSH-R expressing human orbital fibroblasts, collected from GH+GO patients (GOF), were stimulated with the monoclonal antibody M22 or with stimulatory TSH-R-Ab (TSAb)-positive sera with cyclic adenosine monophosphate (cAMP) or hyaluronic acid (HA) release as readouts. The effect of SYD5115 on the viability of GOF was tested in 4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide and scratch cell growth assays. Results: SYD5115 significantly and dose dependently inhibited the TSH-R activation through M22 or TSAb-positive sera in all performed bioassays. Inhibition showed similar levels in the TSAb reporter bioassay and in the cAMP assay with GOF. The % inhibition and compound concentration showed a sigmoidal relationship, with all seven TSAb-positive sera markedly inhibited by SYD5115. An SYD5115 dose-dependent inhibition of M22 (10 ng/mL, 6 hours)-stimulated HA and/or cAMP-release from GOF was observed. Strong SYD5115-induced inhibitions of M22-stimulated cAMP production in GOF were registered with SYD5115 concentrations of 1 (p = 0.0029), 10 (p < 0.0001), 100 (p < 0.0001), 1,000 (p < 0.0001), and 10,000 (p < 0.0001) nM, respectively. SYD5115-induced inhibition of M22-stimulated HA production was noted with SYD5115 concentrations of 100 (p = 0.0392), 1000 (p = 0.0431), and 10,000 (p = 0.0245) nM, respectively. The inhibitory activity of SYD5115 was confirmed in a human osteosarcoma U2OS cell line stably expressing human TSH-R with cAMP as readout. SYD5115 induced 100% inhibition of the M22-induced cAMP levels with a potency of 193 nM. Compared with control, SYD5115 did neither impact the growth nor the migration of cultivated GOF. In addition, SYD5115 did not alter the viability of GOF. Conclusions: SYD5115 blocked M22- and TSAb-induced TSH-R activity with a nanomolar potency in TSH-R-overexpressed CHO cells as well as primary GOF, which demonstrates the ability of this small molecule to block TSH-R overactivity.


Assuntos
Oftalmopatia de Graves , Receptores da Tireotropina , Cricetinae , Animais , Humanos , Oftalmopatia de Graves/tratamento farmacológico , Cricetulus , Células CHO , Imunoglobulinas Estimuladoras da Glândula Tireoide , Tireotropina/metabolismo , Autoanticorpos
3.
Proc Natl Acad Sci U S A ; 118(51)2021 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-34911759

RESUMO

Chiral asymmetry is important in a wide variety of disciplines and occurs across length scales. While several natural chiral biomolecules exist only with single handedness, they can produce complex hierarchical structures with opposite chiralities. Understanding how the handedness is transferred from molecular to the macroscopic scales is far from trivial. An intriguing example is the transfer of the handedness of helicoidal organizations of cellulose microfibrils in plant cell walls. These cellulose helicoids produce structural colors if their dimension is comparable to the wavelength of visible light. All previously reported examples of a helicoidal structure in plants are left-handed except, remarkably, in the Pollia condensata fruit; both left- and right-handed helicoidal cell walls are found in neighboring cells of the same tissue. By simultaneously studying optical and mechanical responses of cells with different handednesses, we propose that the chirality of helicoids results from differences in cell wall composition. In detail, here we showed statistical substantiation of three different observations: 1) light reflected from right-handed cells is red shifted compared to light reflected from left-handed cells, 2) right-handed cells occur more rarely than left-handed ones, and 3) right-handed cells are located mainly in regions corresponding to interlocular divisions. Finally, 4) right-handed cells have an average lower elastic modulus compared to left-handed cells of the same color. Our findings, combined with mechanical simulation, suggest that the different chiralities of helicoids in the cell wall may result from different chemical composition, which strengthens previous hypotheses that hemicellulose might mediate the rotations of cellulose microfibrils.


Assuntos
Parede Celular/química , Commelinaceae/química , Frutas/química , Parede Celular/ultraestrutura , Celulose/química , Cor , Módulo de Elasticidade , Microfibrilas/química , Polissacarídeos/química
5.
Biotechnol Biofuels ; 14(1): 78, 2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33781321

RESUMO

Plant cell wall-derived biomass serves as a renewable source of energy and materials with increasing importance. The cell walls are biomacromolecular assemblies defined by a fine arrangement of different classes of polysaccharides, proteoglycans, and aromatic polymers and are one of the most complex structures in Nature. One of the most challenging tasks of cell biology and biomass biotechnology research is to image the structure and organization of this complex matrix, as well as to visualize the compartmentalized, multiplayer biosynthetic machineries that build the elaborate cell wall architecture. Better knowledge of the plant cells, cell walls, and whole tissue is essential for bioengineering efforts and for designing efficient strategies of industrial deconstruction of the cell wall-derived biomass and its saccharification. Cell wall-directed molecular probes and analysis by light microscopy, which is capable of imaging with a high level of specificity, little sample processing, and often in real time, are important tools to understand cell wall assemblies. This review provides a comprehensive overview about the possibilities for fluorescence label-based imaging techniques and a variety of probing methods, discussing both well-established and emerging tools. Examples of applications of these tools are provided. We also list and discuss the advantages and limitations of the methods. Specifically, we elaborate on what are the most important considerations when applying a particular technique for plants, the potential for future development, and how the plant cell wall field might be inspired by advances in the biomedical and general cell biology fields.

6.
Biomacromolecules ; 20(7): 2830-2838, 2019 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-31244020

RESUMO

As with many other biosourced colloids, chitin nanocrystals (ChNCs) can form liquid crystalline phases with chiral nematic ordering. In this work, we demonstrate that it is possible to finely tune the liquid crystalline behavior of aqueous ChNC suspensions finely. Such control was made possible by carefully studying how the hydrolysis conditions and suspension treatments affect the colloidal and self-assembly properties of ChNCs. Specifically, we systematically investigated the effects of duration and acidity of chitin hydrolysis required to extract ChNCs, as well as the effects of the tip sonication energy input, degree of acetylation, pH and ionic strength. Finally, we show that by controlled water evaporation, it is possible to retain and control the helicoidal ordering in dry films, leading to a hierarchical architecture analogous to that found in nature, e.g. in crab shells. We believe that this work serves as a comprehensive insight into ChNC preparation and handling which is required to unlock the full potential of this material in both a scientific and industrial context.


Assuntos
Celulose/química , Quitina/química , Nanopartículas/química , Água/química , Hidrólise , Concentração Osmolar , Suspensões/química
7.
J Am Assoc Lab Anim Sci ; 58(4): 450-455, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31064613

RESUMO

The Guide recommends sanitizing cage components, including microisolation cage tops (MCT), at a minimum of every 2 wk. Previously published data demonstrated that mouse MCT microbial loads do not increase until at least 2 wk and that sanitation can be delayed past 2 wk. How microbial loads differ on mouse compared with rat MCT, as well as across different ventilation systems, remains unclear. We hypothesized that MCT microbial loads would be higher in tops from rats compared with mice and would differ according to IVC ventilation system. We evaluated bacterial loads on MCT at serial time points to 90 d from static cages housing mice or rats and from rat and mouse cages on several ventilation systems (mice, 6; rats, 4). MCT were determined to have sufficiently elevated bacterial loads to necessitate changing based on either statistically significant changes in bacterial loads or values greater than 50 cfu. Across all ventilation systems, bacterial counts at 14 d were significantly higher on rat MCT compared with mouse MCT. Across the ventilation systems examined, rat MCT cfu remained similarly elevated from 14 d through 90 d. Mouse MCT total cfu were also stable across multiple ventilation systems yet remained lower than 50 cfu until at least 90 d. Patterns of bacterial species isolated from rat MCT were relatively consistent over time and ventilation system, whereas mice showed greater variability in both contexts. We found that 14 d is an appropriate sanitization time point for rat MCT, whereas the interval at which mouse MCT are cleaned can be extended to 90 d at least. Our data highlight interspecies differences in the accumulation of bacteria on MCT and that mouse MCT sanitation intervals for several housing systems can be extended beyond 14 d.


Assuntos
Bactérias/isolamento & purificação , Contaminação de Equipamentos , Abrigo para Animais/normas , Ventilação , Animais , Ciência dos Animais de Laboratório , Masculino , Camundongos , Ratos , Saneamento , Especificidade da Espécie
8.
Interface Focus ; 9(1): 20180055, 2019 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-30603073

RESUMO

Blue and near-ultraviolet structural colours have often been reported in understorey plants living in deep shade. While this intense blue coloration is very catchy to the eye of a human observer, there are cases in which structural colours can be hidden either by the scattered light interacting with pigments or because they are found in unexpected positions in the plants. Here, we show that the fronds of Microsorum thailandicum produce structural coloration on both the adaxial and abaxial epidermal surface. While cellulose helicoidal structures are responsible for this coloration in both epidermal layers, the reflected colours are consistently different: an intense blue reflection is found in the adaxial epidermis while red-shifted and less intense colours are observed in the abaxial epidermis, possibly suggesting photo-adaptation of the plant to the light environment. By comparing the optical properties of the fern with its anatomy we computed the theoretical reflection accounting for the presence of disorder in the cellulose helicoidal architecture.

9.
PeerJ ; 5: e3059, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28286714

RESUMO

The True's beaked whale (Mesoplodon mirus, True 1913) is a poorly known member of the Ziphiidae family. Its distribution in the northern hemisphere is thought to be restricted to the temperate or warm temperate waters of the North Atlantic, while a few stranding records from the southern hemisphere suggest a wider and antitropical distribution, extending to waters from the Atlantic coast of Brazil to South Africa, Mozambique, Australia and the Tasman Sea coast of New Zealand. This paper (i) reports the first molecular confirmation of the occurrence of the True's beaked whale at the southern limit of its distribution recorded in the northeast Atlantic: the Azores and Canary Islands (macaronesian ecoregion); (ii) describes a new colouration for this species using evidence from a whale with molecular species confirmation; and (iii) contributes to the sparse worldwide database of live sightings, including the first underwater video recording of this species and close images of a calf. Species identification was confirmed in two cases using mitochondrial DNA control region and cytochrome b gene markers: a subadult male True's beaked whale that stranded in El Hierro, Canary Islands, in November 2012, and a subadult male found floating dead near Faial, the Azores, in July 2004. The whale that stranded in the Canary Islands had a clearly delimited white area on its head, extending posteriorly from the tip of the beak to cover the blowhole dorsally and the gular grooves ventrally. This colouration contrasts with previous descriptions for the species and it may be rare, but it exemplifies the variability of the colouration of True's beaked whales in the North Atlantic, further confirmed here by live sightings data. The recording of several observations of this species in deep but relatively coastal waters off the Azores and the Canary Islands suggests that these archipelagos may be unique locations to study the behaviour of the enigmatic True's beaked whale.

10.
J Relig Health ; 56(6): 1937-1955, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27485298

RESUMO

This research study was designed to examine the effect of spiritual well-being and spirituality on state and trait anxiety. Two hundred and thirty-eight adults in the USA were surveyed using the State-Trait Anxiety Inventory, Duke University Religion Index, Spiritual Well-Being Scale, and Participant Questionnaire. Results indicate that spiritual well-being can predict 39.1 % of an adult's state anxiety and 37.9 % of trait anxiety. Furthermore, frequency of religious attendance, frequency of private religious activity, and intrinsic religiosity can predict 6.2 % of an adult's state anxiety and 8.6 % of trait anxiety. Recommendations for researchers and implications for clinicians are discussed.


Assuntos
Transtornos de Ansiedade/psicologia , Espiritualidade , Adaptação Psicológica , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Estados Unidos , Adulto Jovem
12.
Hum Factors ; 56(2): 384-91, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24689255

RESUMO

OBJECTIVE: The authors examine the pattern of direction errors made during the manipulation of a physical simulation of an underground coal mine bolting machine to assess the directional control-response compatibility relationships associated with the device and to compare these results to data obtained from a virtual simulation of a generic device. BACKGROUND: Directional errors during the manual control of underground coal roof bolting equipment are associated with serious injuries. Directional control-response relationships have previously been examined using a virtual simulation of a generic device; however, the applicability of these results to a specific physical device may be questioned. METHOD: Forty-eight participants randomly assigned to different directional control-response relationships manipulated horizontal or vertical control levers to move a simulated bolter arm in three directions (elevation, slew, and sump) as well as to cause a light to become illuminated and raise or lower a stabilizing jack. Directional errors were recorded during the completion of 240 trials by each participant RESULTS: Directional error rates are increased when the control and response are in opposite directions or if the direction of the control and response are perpendicular.The pattern of direction error rates was consistent with experiments obtained from a generic device in a virtual environment. CONCLUSION: Error rates are increased by incompatible directional control-response relationships. APPLICATION: Ensuring that the design of equipment controls maintains compatible directional control-response relationships has potential to reduce the errors made in high-risk situations, such as underground coal mining.


Assuntos
Acidentes de Trabalho/estatística & dados numéricos , Minas de Carvão/instrumentação , Análise e Desempenho de Tarefas , Interface Usuário-Computador , Acidentes de Trabalho/prevenção & controle , Adulto , Desenho de Equipamento , Ergonomia , Feminino , Humanos , Masculino , Sistemas Homem-Máquina , Pessoa de Meia-Idade , Gestão da Segurança , Adulto Jovem
13.
J Safety Res ; 44: 37-44, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23398703

RESUMO

PROBLEM: Operators of roof bolting machines in underground coal mines do so in confined spaces and in very close proximity to the moving equipment. Errors in the operation of these machines can have serious consequences, and the design of the equipment interface has a critical role in reducing the probability of such errors. METHODS: An experiment was conducted to explore coding and directional compatibility on actual roof bolting equipment and to determine the feasibility of a visual feedback system to alert operators of critical movements and to also alert other workers in close proximity to the equipment to the pending movement of the machine. The quantitative results of the study confirmed the potential for both selection errors and direction errors to be made, particularly during training. RESULTS: Subjective data confirmed a potential benefit of providing visual feedback of the intended operations and movements of the equipment. IMPACT: This research may influence the design of these and other similar control systems to provide evidence for the use of warning systems to improve operator situational awareness.


Assuntos
Minas de Carvão , Desenho de Equipamento , Retroalimentação Sensorial , Acidentes de Trabalho/prevenção & controle , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Ferimentos e Lesões/prevenção & controle , Adulto Jovem
14.
Chembiochem ; 14(4): 436-9, 2013 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-23418022

RESUMO

PROMISCUOUS ENZYMES: The substrate promiscuity of squalene-hopene cyclases has been explored and applied in the enzyme-catalyzed synthesis of heterocyclic terpenoids. Features of this work include cyclization reactions without pyrophosphate activation, and stereospecific ring closure of substrates of varying chain length and terminal nucleophile. This provides a biocatalytic alternative to traditional chemical catalysts.


Assuntos
Alicyclobacillus/enzimologia , Transferases Intramoleculares/metabolismo , Terpenos/química , Terpenos/metabolismo , Alicyclobacillus/metabolismo , Ciclização , Modelos Moleculares , Especificidade por Substrato
15.
J Clin Microbiol ; 51(4): 1285-7, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23363831

RESUMO

This case series highlights our experience with use of the Fungitell assay for quantifying (1,3)-ß-d-glucan in cerebrospinal fluid during the current U.S. outbreak of fungal meningitis related to contaminated methylprednisolone acetate. This test may prove a useful adjunct in diagnosis and management of exposed patients.


Assuntos
Líquido Cefalorraquidiano/química , Doença Iatrogênica , Meningite Fúngica/diagnóstico , beta-Glucanas/líquido cefalorraquidiano , Adulto , Idoso , Contaminação de Medicamentos , Feminino , Humanos , Masculino , Metilprednisolona/administração & dosagem , Metilprednisolona/efeitos adversos , Metilprednisolona/análogos & derivados , Acetato de Metilprednisolona , Pessoa de Meia-Idade , Proteoglicanas
16.
Mol Immunol ; 48(15-16): 2220-3, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21820179

RESUMO

The zebrafish is an emerging model for comparative immunology and biomedical research. In contrast to the five heavy chain isotype system of mice and human (IgD, IgM, IgA, IgG, IgE), zebrafish harbor gene segments for IgD, IgM, and novel heavy chain isotype called IgZ/T which appears restricted to bony fishes. The purpose of this study was to design and validate a suite of quantitative real time RT-PCR protocols to measure IgH expression in a vertebrate model which has considerable promise for modeling both pathogenic infection and chronic conditions leading to immune dysfunction. Specific primers were designed and following verification of their specificty, relative expression levels of IgD, IgM, and IgZ/T were measured in triplicate for zebrafish raised under standard laboratory conditions. During embryonic stages, low levels of each heavy chain isotype (IgH) were detected with each increasing steadily between 2 and 17 weeks post fertilization. Overall IgM>IgZ>IgD throughout zebrafish development with the copy number of IgM being several fold higher than that of IgD or IgZ/T. IgD exon usage was also characterized, as its extremely long size and presence of a stop codon in the second IgD exon in zebrafish, raised questions as to how this antibody might be expressed. Zebrafish IgD was found to be a chimeric immunoglobulin, with the third IgD exon spliced to the first IgM constant exon thereby circumventing the first and second IgD exons. Collectively, the qRT-PCR results represent the first comparative profile of IgD, IgM, IgZ/T expression over the lifespan of any fish species and the primers and assay parameters reported should prove useful in enabling researchers to rapidly quantify changes in IgH expression in zebrafish models of disease where altered IgH expression is manifested.


Assuntos
Perfilação da Expressão Gênica , Imunoglobulina D/genética , Cadeias Pesadas de Imunoglobulinas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Peixe-Zebra/genética , Peixe-Zebra/imunologia , Animais , Éxons , Expressão Gênica , Rearranjo Gênico do Linfócito B/genética , Cadeias Pesadas de Imunoglobulinas/análise , Isotipos de Imunoglobulinas/genética , Isotipos de Imunoglobulinas/imunologia , Imunoglobulina M/genética , Imunoglobulina M/imunologia , Splicing de RNA , Peixe-Zebra/crescimento & desenvolvimento
17.
Inorg Chem ; 50(5): 1983-90, 2011 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-21261279

RESUMO

We synthesized and characterized a set of new oxorhenium(V) complexes coordinated by various pyrazole containing phenol (L1-L3) and naphthol ligands (L4-L7). Depending on the starting material, we were able to selectively synthesize monosubstituded or disubstituted complexes of the type [ReOBr(2)L(PPh(3))] (1-7; L = L1-L7) and [ReOClL(2)] (L = L1 8; L2 9; L4 10; L6 11), respectively. All complexes are stable to air and moisture, both in solid state as well as in solution. Furthermore, the cationic oxorhenium(V) complex [ReO(L1)(2)(NCMe)](OTf) (8a) was obtained upon chloride abstraction with silver triflate from 8. All new complexes were able to catalyze the epoxidation of cis-cyclooctene in yields up to 64%. The ease of preparation and their tolerance to air and moisture, as well as the simple ligand modifications, make them an interesting class of novel catalysts. An attempted reduction of perchlorate ClO(4)(-) with complex 8 was unsuccessful. Molecular structures of complexes 1, 4, 6, 7, 8, 8a, 10, and 11 were determined by single crystal X-ray diffraction analyses.

18.
Appl Ergon ; 41(4): 549-55, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20015480

RESUMO

Selecting the incorrect control during the operation of underground bolting and drilling equipment causes serious injuries. Shape coding and the layout of dual control banks are two aspects of control design which require further examination. The aims of this research were: (i) to determine whether arbitrary shape coding was effective in reducing selection error rates in a virtual analogy of roof-bolting; and (ii) to determine whether any advantages exist for mirror or place layouts for dual control situations in this situation. Two experiments were conducted to address these questions. No benefits of arbitrary shape coding were evident while control location remained constant. When control location was altered, shape coding did provide a significant reduction in selection error rate. No differences between mirror or place arrangements were detected and this question remains open.


Assuntos
Comportamento de Escolha , Desenho de Equipamento , Mineração , Saúde Ocupacional , Humanos , Pesquisa , Gestão da Segurança , Análise e Desempenho de Tarefas
19.
Dev Comp Immunol ; 32(4): 421-34, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18022691

RESUMO

In mammals, Immunoglobulin light chain (IgL) are localized to two chromosomal regions (designated kappa and lambda). Here we report a genome-wide survey of IgL genes in the zebrafish revealing (V(L)-J(L)-C(L)) clusters spanning 5 separate chromosomes. To elucidate IgL loci present in the zebrafish genome assembly (Zv6), conventional sequence similarity searches and a novel scanning approach based on recombination signal sequence (RSS) motifs were applied. RT-PCR with zebrafish cDNA was used to confirm annotations, evaluate VJ-rearrangement possibilities and show that each chromosomal locus is expressed. In contrast to other vertebrates in which IgL exon usage has been studied, inversional rearrangement between (V(L)-J(L)-C(L)) clusters were found. Inter-cluster rearrangements may convey a selective advantage for editing self-reactive receptors and poise zebrafish by virtue of their extensive numbers of V(L), J(L) and C(L) to have greater potential for immunoglobulin gene shuffling than traditionally studied mice and human models.


Assuntos
Rearranjo Gênico de Cadeia Leve de Linfócito B , Genes de Cadeia Leve de Imunoglobulina , Cadeias Leves de Imunoglobulina/genética , Peixe-Zebra/genética , Peixe-Zebra/imunologia , Sequência de Aminoácidos , Animais , Cromossomos/genética , Regiões Constantes de Imunoglobulina/genética , Região de Junção de Imunoglobulinas/genética , Cadeias Leves de Imunoglobulina/química , Cadeias Leves de Imunoglobulina/imunologia , Região Variável de Imunoglobulina/genética , Dados de Sequência Molecular , Família Multigênica , Filogenia , Alinhamento de Sequência , Análise de Sequência de DNA
20.
Immunogenetics ; 59(9): 735-44, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17701034

RESUMO

Terminal deoxynucleotidyl transferase (TdT) contributes to the junctional diversity of immunoglobulin and T-cell receptors by incorporating nucleotides in a template-independent manner. A closely related enzyme, polymerase mu (polmu), a template-directed polymerase, plays a role in general end-joining double-strand break repair. We cloned zebrafish TdT and polmu and found them to be 43% identical in amino acid sequence. Comparisons with sequences of other species revealed conserved residues typical for TdT in the zebrafish sequence that support the template independence of this enzyme. Some but not all of these features were identified in zebrafish polmu. In adult fish, TdT expression was most prominent in thymus, pro- and mesonephros, the primary lymphoid organs in teleost fish and in spleen, intestine, and the tissue around the intestine. Polmu expression was detected not only in pro- and mesonephros, the major sites for B-lymphocyte development, but also in ovary and testis and in all tissue preparations to a low extent. TdT expression starts at 4 dpf and increases thereafter. Polmu is expressed at all times to a similar extent. In situ studies showed a strong expression of TdT and polmicro in the thymic cortex of 8-week-old fish. The characterization of zebrafish TdT and polmu provide new insights in fish lymphopoiesis and addresses the importance and evolution of TdT and polmu themselves.


Assuntos
DNA Nucleotidilexotransferase/metabolismo , DNA Polimerase Dirigida por DNA/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/metabolismo , Sequência de Aminoácidos , Animais , DNA Nucleotidilexotransferase/genética , DNA Polimerase Dirigida por DNA/genética , Dados de Sequência Molecular , Especificidade de Órgãos , Filogenia
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