RESUMO
The Aspirin in Reducing Events in the Elderly (ASPREE) Trial recruited 19,114 participants across Australia and the United States during 2010-2014. Participants were randomized to receive either 100 mg of aspirin daily or matching placebo, with disability-free survival as the primary outcome. During a median 4.7 years of follow-up, 37% of participants in the aspirin group permanently ceased taking their study medication and 10% commenced open-label aspirin use. In the placebo group, 35% and 11% ceased using study medication and commenced open-label aspirin use, respectively. In order to estimate compliance-adjusted effects of aspirin, we applied rank-preserving structural failure time models. The results for disability-free survival and most secondary endpoints were similar in intention-to-treat and compliance-adjusted analyses. For major hemorrhage, cancer mortality, and all-cause mortality, compliance-adjusted effects of aspirin indicated greater risks than were seen in intention-to-treat analyses. These findings were robust in a range of sensitivity analyses. In accordance with the original trial analyses, compliance-adjusted results showed an absence of benefit with aspirin for primary prevention in older people, along with an elevated risk of clinically significant bleeding.
Assuntos
Aspirina , Hemorragia , Humanos , Estados Unidos/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Aspirina/uso terapêutico , Hemorragia/induzido quimicamente , Austrália/epidemiologia , Método Duplo-CegoRESUMO
In addition to naturally occurring sequence variation and spontaneous mutations, a wide array of technologies exist for modifying the mouse genome. Standardized nomenclature, including allele, transgene, and other mutation nomenclature, as well as persistent unique identifiers (PUID) are critical for effective scientific communication, comparison of results, and integration of data into knowledgebases such as Mouse Genome Informatics (MGI), Alliance for Genome Resources, and International Mouse Strain Resource (IMSR). As well as being the authoritative source for mouse gene, allele, and strain nomenclature, MGI integrates published and unpublished genomic, phenotypic, and expression data while linking to other online resources for a complete view of the mouse as a valuable model organism. The International Committee on Standardized Genetic Nomenclature for Mice has developed allele nomenclature rules and guidelines that take into account the number of genes impacted, the method of allele generation, and the nature of the sequence alteration. To capture details that cannot be included in allele symbols, MGI has further developed allele to gene relationships using sequence ontology (SO) definitions for mutations that provide links between alleles and the genes affected. MGI is also using (HGVS) variant nomenclature for variants associated with alleles that will enhance searching for mutations and will improve cross-species comparison. With the ability to assign unique and informative symbols as well as to link alleles with more than one gene, allele and transgene nomenclature rules and guidelines provide an unambiguous way to represent alterations in the mouse genome and facilitate data integration among multiple resources such the Alliance of Genome Resources and International Mouse Strain Resource.
Assuntos
Bases de Dados Genéticas , Genômica , Alelos , Animais , Genômica/métodos , Camundongos , Mutação , TransgenesRESUMO
BACKGROUND: Eosinophilic esophagitis (EoE) is an atopic disease characterized by eosinophilic inflammation in which dietary antigens (in particular, milk) play a major role. EoE is most likely a mixed IgE and non-IgE food-mediated reaction in which overexpression of Th2 cytokines, particularly IL-13, play a major role; however, the cells responsible for IL-13 overexpression remain elusive. Th2-cytokines are secreted following the ligation of invariant natural killer T cell receptors to sphingolipids (SLs). Sphingolipids (SLs) are presented via the CD1d molecule on the INKTs surface. Cow's milk-derived SL has been shown to activate iNKTs from children with IgE-mediated food allergies to milk (FA-MA) to produce Th2 cytokines. The role of iNKTs and milk-SL in EoE pathogenesis is currently unknown. OBJECTIVE: The aim of this study was to investigate the role of iNKTs and milk-SL in EoE. METHODS: Peripheral blood mononuclear cells (PBMCs) from 10 children with active EoE (EoE-A), 10 children with controlled EoE (EoE-C) and 16 healthy controls (non-EoE) were measured ex vivo and then incubated with α-galactosylceramide (αGal) and milk-SL. INKTs from peripheral blood (PB) and oesophageal biopsies were studied. RESULTS: EoE-A children had significantly fewer peripheral blood iNKTs with a greater Th2-response to αGal and milk-SM compared with iNKTs of EoE-C and non-EoE children. Additionally, EoE-A children had increased iNKT levels in oesophageal biopsies compared with EoE-C children. CONCLUSION: Milk-SLs are able to activate peripheral blood iNKTs in EoE-A children to produce Th2 cytokines. Additionally, iNKT levels are higher at the site of active oesophageal eosinophilic inflammation. CLINICAL RELEVANCE: This study suggests that sphingolipids (SLs) contained in milk may drive the development of EoE by promoting an iNKT-cell-mediated Th2-type cytokine response that facilitates eosinophil-mediated allergic inflammation.
Assuntos
Esofagite Eosinofílica/imunologia , Células T Matadoras Naturais/imunologia , Adolescente , Alérgenos/imunologia , Animais , Criança , Pré-Escolar , Citocinas/biossíntese , Esofagite Eosinofílica/tratamento farmacológico , Esofagite Eosinofílica/metabolismo , Feminino , Humanos , Imunofenotipagem , Contagem de Linfócitos , Masculino , Leite/imunologia , Células T Matadoras Naturais/metabolismo , Fenótipo , Receptores CCR3/metabolismo , Receptores CCR4/metabolismo , Receptores CCR5/metabolismo , Células Th2/imunologia , Células Th2/metabolismoRESUMO
BACKGROUND: Several rating scales have been developed to measure quality of recovery after surgery and anaesthesia, but the most extensively used is the QoR-40, a 40-item questionnaire that provides a global score and subscores across five dimensions: patient support, comfort, emotions, physical independence, and pain. It has been evaluated in a variety of settings, but its overall psychometric properties (validity, reliability, ease of use, and interpretation) and clinical utility are uncertain. METHODS: We undertook a quantitative systematic review of studies evaluating psychometric properties of the QoR-40. Data were combined in meta-analyses using random effects models. This resulted in a total sample of 3459 patients from 17 studies originating in nine countries. RESULTS: We confirmed content, construct, and convergent [pooled r=0.58, 95% confidence interval (CI): 0.51-0.65] validity. Reliability was confirmed by excellent intraclass correlation (pooled α=0.91, 95% CI: 0.88-0.93), test-retest reliability (pooled r=0.90, 95% CI: 0.86-0.92), and inter-rater reliability (intraclass correlation=0.86). The clinical utility of the QoR-40 instrument was supported by high patient recruitment into evaluation studies (97%), and an excellent completion and return rate (97%). The mean time to complete the QoR-40 was 5.1 (95% CI: 4.4-5.7) min. CONCLUSIONS: The QoR-40 is a widely used and extensively validated measure of quality of recovery. The QoR-40 is a suitable measure of postoperative quality of recovery in a range of clinical and research situations.
Assuntos
Período de Recuperação da Anestesia , Inquéritos e Questionários/normas , Idoso de 80 Anos ou mais , Anestesia , Humanos , Satisfação do Paciente/estatística & dados numéricos , Período Pós-Operatório , Psicometria , Reprodutibilidade dos TestesRESUMO
Various pests, such as those in the order Lepidoptera, frequently feed on young maize (Zea mays) plants and pose a significant threat to plant development and survival. To manage this problem, maize generates a wide variety of responses to attack by pests, from activation of wound-response pathways to the release of volatile compounds. Mp708, an inbred line resistant to feeding by the larvae of the fall armyworm (Spodoptera frugiperda J.E. Smith Lepidoptera: Noctuidae), has been developed through traditional breeding methods, but its underlying mechanisms of resistance are still not completely understood. Mp708 has been shown to have a moderately high constitutive expression of jasmonic acid (JA) before infestation by fall armyworm. However, Tx601, a genotype susceptible to feeding by fall armyworm, activates JA pathway only in response to feeding, suggesting that Mp708 is "primed" to respond swiftly to an attack. Current research indicates that fall armyworm show a lack of preference to feeding on Mp708, leading to the hypothesis that volatiles constitutively released by the plant may also play an important role in its resistance. Analysis of volatiles released by Mp708 and Tx601 in the presence and absence of fall armyworm larvae identified (E)-beta-caryophyllene, a terpenoid associated with resistance, released constitutively in Mp708. Fall armyworm fed samples of both Mp708 and Tx601 showed high transcript number of tps23, the gene responsible for the synthesis of (E)-beta-caryophyllene. In addition, fall armyworm larvae show a preference for Tx601 whorl tissue over Mp708 tissue, and the dosage of Tx601 whorl with (E)-beta-caryophyllene repels the fall armyworm.
Assuntos
Alquil e Aril Transferases/metabolismo , Ciclopentanos/metabolismo , Oxilipinas/metabolismo , Sesquiterpenos/metabolismo , Spodoptera/fisiologia , Zea mays/metabolismo , Alquil e Aril Transferases/genética , Animais , Preferências Alimentares , Herbivoria , Larva/crescimento & desenvolvimento , Larva/fisiologia , Folhas de Planta/genética , Sesquiterpenos Policíclicos , Reação em Cadeia da Polimerase em Tempo Real , Spodoptera/crescimento & desenvolvimento , Zea mays/genéticaRESUMO
Evidence from Europe suggests establishing out-of-hospital, uncontrolled donation after circulatory determination of death (UDCDD) protocols has potential to substantially increase organ availability. The study objective was to derive an out-of-hospital UDCDD protocol that would be acceptable to New York City (NYC) residents. Participatory action research and the SEED-SCALE process for social change guided protocol development in NYC from July 2007 to September 2010. A coalition of government officials, subject experts and communities necessary to achieve support was formed. Authorized NY State and NYC government officials and their legal representatives collaboratively investigated how the program could be implemented under current law and regulations. Community stakeholders (secular and religious organizations) were engaged in town hall style meetings. Ethnographic data (meeting minutes, field notes, quantitative surveys) were collected and posted in a collaborative internet environment. Data were analyzed using an iterative coding scheme to discern themes, theoretical constructs and a summary narrative to guide protocol development. A clinically appropriate, ethically sound UDCDD protocol for out-of-hospital settings has been derived. This program is likely to be accepted by NYC residents since the protocol was derived through partnership with government officials, subject experts and community participants.
Assuntos
Morte , Obtenção de Tecidos e Órgãos/legislação & jurisprudência , Pesquisa Participativa Baseada na Comunidade , Humanos , Consentimento Livre e Esclarecido , Cidade de Nova Iorque , Parada Cardíaca Extra-Hospitalar , Obtenção de Tecidos e Órgãos/métodos , Isquemia QuenteRESUMO
Here we report the use of fluorescence recovery after photobleaching (FRAP) to examine the intranuclear dynamics of fluorescent oestrogen receptor-alpha (ER). After bleaching, unliganded ER exhibits high mobility (recovery t1/2 < 1 s). Agonist (oestradiol; E2) or partial antagonist (4-hydroxytamoxifen) slows ER recovery (t1/2 approximately 5-6 s), whereas the pure antagonist (ICI 182,780) and, surprisingly, proteasome inhibitors each immobilize ER to the nuclear matrix. Dual FRAP experiments show that fluorescent ER and SRC-1 exhibit similar dynamics only in the presence of E2. In contrast to reports that several nuclear proteins show uniform dynamics, ER exhibits differential mobility depending upon several factors that are linked to its transcription function.
Assuntos
Transporte Biológico/genética , Cisteína Endopeptidases/metabolismo , Estradiol/análogos & derivados , Estradiol/farmacologia , Antagonistas de Estrogênios/farmacologia , Complexos Multienzimáticos/metabolismo , Matriz Nuclear/metabolismo , Receptores de Estrogênio/metabolismo , Tamoxifeno/análogos & derivados , Transcrição Gênica/fisiologia , Proteínas de Bactérias/análise , Transporte Biológico/efeitos dos fármacos , Inibidores de Cisteína Proteinase/farmacologia , Dactinomicina/farmacologia , Receptor alfa de Estrogênio , Fulvestranto , Células HeLa , Histona Acetiltransferases , Humanos , Leupeptinas/farmacologia , Ligantes , Proteínas Luminescentes/análise , Microscopia de Fluorescência/métodos , Complexos Multienzimáticos/antagonistas & inibidores , Matriz Nuclear/efeitos dos fármacos , Coativador 1 de Receptor Nuclear , Complexo de Endopeptidases do Proteassoma , Estrutura Terciária de Proteína/efeitos dos fármacos , Estrutura Terciária de Proteína/fisiologia , Receptores de Estrogênio/efeitos dos fármacos , Receptores de Estrogênio/genética , Tamoxifeno/farmacologia , Fatores de Transcrição/efeitos dos fármacos , Fatores de Transcrição/metabolismo , Transcrição Gênica/efeitos dos fármacosRESUMO
Intravascular large B cell lymphoma (IVLBCL) is a rare cause of pyrexia of unknown origin. Because of its protean clinical manifestations, diagnosis is elusive and is often made postmortem. We report here a case of IVLBCL that evaded diagnosis despite multiple investigations in vivo for pyrexia of unknown origin over a 5‐month period.
Assuntos
Febre de Causa Desconhecida/etiologia , Linfoma de Células B/complicações , Linfoma de Células B/diagnóstico , Neoplasias Vasculares/complicações , Neoplasias Vasculares/diagnóstico , Idoso , Antígenos CD20/análise , Evolução Fatal , Feminino , Humanos , Imuno-Histoquímica , Linfoma de Células B/patologia , Microscopia , Neoplasias Vasculares/patologiaRESUMO
In healthy cells, fusion and fission events participate in regulating mitochondrial morphology. Disintegration of the mitochondrial reticulum into multiple punctiform organelles during apoptosis led us to examine the role of Drp1, a dynamin-related protein that mediates outer mitochondrial membrane fission. Upon induction of apoptosis, Drp1 translocates from the cytosol to mitochondria, where it preferentially localizes to potential sites of organelle division. Inhibition of Drp1 by overexpression of a dominant-negative mutant counteracts the conversion to a punctiform mitochondrial phenotype, prevents the loss of the mitochondrial membrane potential and the release of cytochrome c, and reveals a reproducible swelling of the organelles. Remarkably, inhibition of Drp1 blocks cell death, implicating mitochondrial fission as an important step in apoptosis.
Assuntos
Apoptose/fisiologia , GTP Fosfo-Hidrolases , Proteínas Associadas aos Microtúbulos , Mitocôndrias/fisiologia , Proteínas/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2 , Animais , Células COS , Grupo dos Citocromos c/metabolismo , Dinaminas , Células HeLa , Humanos , Membranas Intracelulares/metabolismo , Membranas Intracelulares/ultraestrutura , Potenciais da Membrana/fisiologia , Microscopia Imunoeletrônica , Mitocôndrias/ultraestrutura , Proteínas Mitocondriais , Dilatação Mitocondrial/fisiologia , Fenótipo , Proteínas/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Transfecção , Proteína X Associada a bcl-2RESUMO
Neurite formation by dissociated chick sympathetic neurons in vitro begins when one of the many filopodia that emanate from the cell body of a neuron is invaded by cytoplasm containing microtubules and other components of axoplasm (Smith, 1994). This study was undertaken to determine whether this process depends on assembly of microtubules. To inhibit microtubule assembly, neurons were grown in medium containing nocodazole or colchicine. In one series of experiments, neurons first were exposed to the microtubule-stabilizing drug, taxol, so that existing microtubules would remain intact while assembly of new microtubules was inhibited. The ability of neurons to form neurites was assessed by time-lapse video microscopy. Neurons subsequently were stained with antibodies against the tyrosinated and acetylated forms of alpha-tubulin and examined by laser confocal microscopy to visualize microtubules. Neurons were able to form short processes despite inhibition of microtubule assembly and they did so in a way that closely resembled process formation in control medium. Processes formed by neurons that had not been pretreated with taxol were devoid of microtubules. However, microtubules were present in processes of taxol-pretreated neurons. These microtubules contained acetylated alpha-tubulin, as is typical of stable microtubules, but not tyrosinated alpha-tubulin, the form present in recently assembled microtubules. These findings show that the initial steps in neurite formation do not depend on microtubule assembly and suggest that microtubules assembled in the cell body can be translocated into developing neurites as they emerge. The results are compatible with models of neurite formation which postulate that cytoplasm from the cell body is transported into filopodia by actomyosin-based motility mechanisms.
Assuntos
Gânglios Simpáticos/citologia , Microtúbulos/fisiologia , Neuritos/fisiologia , Neurônios/fisiologia , Animais , Células Cultivadas , Embrião de Galinha , Colchicina/farmacologia , Gânglios Simpáticos/fisiologia , Gânglios Simpáticos/ultraestrutura , Microscopia Confocal , Microscopia de Vídeo , Microtúbulos/efeitos dos fármacos , Neuritos/ultraestrutura , Neurônios/ultraestrutura , Nocodazol/farmacologia , Paclitaxel/farmacologia , Tubulina (Proteína)/metabolismoRESUMO
Bax is a member of the Bcl-2 family of proteins known to regulate mitochondria-dependent programmed cell death. Early in apoptosis, Bax translocates from the cytosol to the mitochondrial membrane. We have identified by confocal and electron microscopy a novel step in the Bax proapoptotic mechanism immediately subsequent to mitochondrial translocation. Bax leaves the mitochondrial membranes and coalesces into large clusters containing thousands of Bax molecules that remain adjacent to mitochondria. Bak, a close homologue of Bax, colocalizes in these apoptotic clusters in contrast to other family members, Bid and Bad, which circumscribe the outer mitochondrial membrane throughout cell death progression. We found the formation of Bax and Bak apoptotic clusters to be caspase independent and inhibited completely and specifically by Bcl-X(L), correlating cluster formation with cytotoxic activity. Our results reveal the importance of a novel structure formed by certain Bcl-2 family members during the process of cell death.
Assuntos
Apoptose , Proteínas de Membrana/metabolismo , Mitocôndrias/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Animais , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3 , Células COS , Proteínas de Transporte/metabolismo , Chlorocebus aethiops , Células HeLa , Humanos , Membranas Intracelulares/metabolismo , Proteínas de Membrana/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Células Tumorais Cultivadas , Proteína Killer-Antagonista Homóloga a bcl-2 , Proteína X Associada a bcl-2 , Proteína de Morte Celular Associada a bcl , Proteína bcl-XRESUMO
Bax, a member of the Bcl-2 protein family, accelerates apoptosis by an unknown mechanism. Bax has been recently reported to be an integral membrane protein associated with organelles or bound to organelles by Bcl-2 or a soluble protein found in the cytosol. To explore Bcl-2 family member localization in living cells, the green fluorescent protein (GFP) was fused to the NH2 termini of Bax, Bcl-2, and Bcl-XL. Confocal microscopy performed on living Cos-7 kidney epithelial cells and L929 fibroblasts revealed that GFP-Bcl-2 and GFP-Bcl-XL had a punctate distribution and colocalized with a mitochondrial marker, whereas GFP-Bax was found diffusely throughout the cytosol. Photobleaching analysis confirmed that GFP-Bax is a soluble protein, in contrast to organelle-bound GFP-Bcl-2. The diffuse localization of GFP-Bax did not change with coexpression of high levels of Bcl-2 or Bcl-XL. However, upon induction of apoptosis, GFP-Bax moved intracellularly to a punctate distribution that partially colocalized with mitochondria. Once initiated, this Bax movement was complete within 30 min, before cellular shrinkage or nuclear condensation. Removal of a COOH-terminal hydrophobic domain from GFP-Bax inhibited redistribution during apoptosis and inhibited the death-promoting activity of both Bax and GFP-Bax. These results demonstrate that in cells undergoing apoptosis, an early, dramatic change occurs in the intracellular localization of Bax, and this redistribution of soluble Bax to organelles appears important for Bax to promote cell death.
Assuntos
Apoptose/fisiologia , Citosol/metabolismo , Mitocôndrias/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Animais , Transporte Biológico , Células COS , Compartimento Celular , Difusão , Proteínas de Fluorescência Verde , Proteínas Luminescentes/isolamento & purificação , Proteínas Luminescentes/metabolismo , Microscopia Confocal , Ligação Proteica , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/isolamento & purificação , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/isolamento & purificação , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/metabolismo , Deleção de Sequência , Células Tumorais Cultivadas , Proteína X Associada a bcl-2 , Proteína bcl-XRESUMO
The mechanisms of localization and retention of membrane proteins in the inner nuclear membrane and the fate of this membrane system during mitosis were studied in living cells using the inner nuclear membrane protein, lamin B receptor, fused to green fluorescent protein (LBR-GFP). Photobleaching techniques revealed the majority of LBR-GFP to be completely immobilized in the nuclear envelope (NE) of interphase cells, suggesting a tight binding to heterochromatin and/or lamins. A subpopulation of LBR-GFP within ER membranes, by contrast, was entirely mobile and diffused rapidly and freely (D = 0. 41 +/- 0.1 microm2/s). High resolution confocal time-lapse imaging in mitotic cells revealed LBR-GFP redistributing into the interconnected ER membrane system in prometaphase, exhibiting the same high mobility and diffusion constant as observed in interphase ER membranes. LBR-GFP rapidly diffused across the cell within the membrane network defined by the ER, suggesting the integrity of the ER was maintained in mitosis, with little or no fragmentation and vesiculation. At the end of mitosis, nuclear membrane reformation coincided with immobilization of LBR-GFP in ER elements at contact sites with chromatin. LBR-GFP-containing ER membranes then wrapped around chromatin over the course of 2-3 min, quickly and efficiently compartmentalizing nuclear material. Expansion of the NE followed over the course of 30-80 min. Thus, selective changes in lateral mobility of LBR-GFP within the ER/NE membrane system form the basis for its localization to the inner nuclear membrane during interphase. Such changes, rather than vesiculation mechanisms, also underlie the redistribution of this molecule during NE disassembly and reformation in mitosis.
Assuntos
Interfase/fisiologia , Mitose/fisiologia , Membrana Nuclear/química , Membrana Nuclear/metabolismo , Receptores Citoplasmáticos e Nucleares/análise , Animais , Células COS , DNA/análise , Retículo Endoplasmático/química , Retículo Endoplasmático/metabolismo , Retículo Endoplasmático/ultraestrutura , Corantes Fluorescentes , Expressão Gênica/fisiologia , Proteínas de Fluorescência Verde , Cinética , Proteínas Luminescentes , Microscopia Eletrônica , Membrana Nuclear/ultraestrutura , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptor de Lamina BRESUMO
An antigen detection system, termed immuno-polymerase chain reaction (immuno-PCR), was developed in which a specific DNA molecule is used as the marker. A streptavidin-protein A chimera that possesses tight and specific binding affinity both for biotin and immunoglobulin G was used to attach a biotinylated DNA specifically to antigen-monoclonal antibody complexes that had been immobilized on microtiter plate wells. Then, a segment of the attached DNA was amplified by PCR. Analysis of the PCR products by agarose gel electrophoresis after staining with ethidium bromide allowed as few as 580 antigen molecules (9.6 x 10(-22) moles) to be readily and reproducibly detected. Direct comparison with enzyme-linked immunosorbent assay with the use of a chimera-alkaline phosphatase conjugate demonstrates that enhancement (approximately x 10(5)) in detection sensitivity was obtained with the use of immuno-PCR. Given the enormous amplification capability and specificity of PCR, this immuno-PCR technology has a sensitivity greater than any existing antigen detection system and, in principle, could be applied to the detection of single antigen molecules.
Assuntos
Antígenos/análise , Reação em Cadeia da Polimerase/métodos , Anticorpos Monoclonais , DNA , Densitometria , Eletroforese em Gel de Ágar , Ensaio de Imunoadsorção Enzimática , Sensibilidade e EspecificidadeRESUMO
A physical map of a genome is the structure of its DNA. Construction of such a map is a first step in the complete characterization of that DNA. The restriction endonuclease Not I cuts the genome of Escherichia coli K12 into 22 DNA fragments ranging from 20 kilobases (20,000 base pairs) to 1000 kilobases. These can be separated by pulsed field gel electrophoresis. The order of the fragments in the genome was determined from available E. coli genetic information and analysis of partial digest patterns. The resulting ordered set of fragments is a macrorestriction map. This map facilitates genetic and molecular studies on E. coli, and its construction serves as a model for further endeavors on larger genomes.
Assuntos
Mapeamento Cromossômico , Escherichia coli/genética , Mapeamento Cromossômico/métodos , Cromossomos Bacterianos , DNA Bacteriano/genética , Hibridização de Ácido NucleicoRESUMO
In the study of the genetic structure of mammalian chromosomes, there exists a "resolution gap" between molecular cloning experiments and meiotic linkage analyses. This gap has discouraged attempts to construct full-scale genetic maps of mammalian chromosomes. The organization of the human major histocompatibility complex was examined within this range by pulsed field gel electrophoresis. The data obtained indicate that the complex spans over 3000 kilobases and enable the construction of a megabase-scale molecular map. These results indicate that the techniques employed in DNA extraction, enzymatic digestion, electrophoresis, and hybridization are suitable for the efficient analysis of megabase regions of mammalian chromosomes and effectively bridge the resolution gap between molecular cloning and classical genetics.
Assuntos
Antígenos HLA/genética , Complexo Principal de Histocompatibilidade , Animais , Composição de Bases , DNA/genética , Enzimas de Restrição do DNA , Eletroforese , Antígenos HLA-D/genética , Humanos , Camundongos , Hibridização de Ácido NucleicoRESUMO
The mechanism by which Golgi membrane proteins are retained within the Golgi complex in the midst of a continuous flow of protein and lipid is not yet understood. The diffusional mobilities of mammalian Golgi membrane proteins fused with green fluorescent protein from Aequorea victoria were measured in living HeLa cells with the fluorescence photobleaching recovery technique. The diffusion coefficients ranged from 3 x 10(-9) square centimeters per second to 5 x 10(-9) square centimeters per second, with greater than 90 percent of the chimeric proteins mobile. Extensive lateral diffusion of the chimeric proteins occurred between Golgi stacks. Thus, the chimeras diffuse rapidly and freely in Golgi membranes, which suggests that Golgi targeting and retention of these molecules does not depend on protein immobilization.
Assuntos
Complexo de Golgi/metabolismo , Manosidases/metabolismo , Proteínas de Membrana/metabolismo , N-Acetil-Lactosamina Sintase/metabolismo , Receptores de Peptídeos/metabolismo , Compostos de Alumínio/farmacologia , Difusão , Retículo Endoplasmático/metabolismo , Fluoretos/farmacologia , Proteínas de Fluorescência Verde , Células HeLa , Humanos , Membranas Intracelulares/metabolismo , Proteínas Luminescentes , Microscopia Confocal , Mutação , Receptores de Peptídeos/genética , Proteínas Recombinantes de Fusão/metabolismoRESUMO
Uterine serous papillary carcinoma (USPC) are high-grade tumors with Her2 gene expression and poor prognosis. The human gene Her2 is a proto-oncogene that encodes a protein with tyrosine kinase activity. The objective of this study was to determine Her2 protein expression and gene amplification in USPC using three methods: immunohistochemistry (IHC), chromogenic in situ hybridization (CISH), and quantitative polymerase chain reaction (Q-PCR), to compare the three techniques, and to correlate Her2 expression and amplification with clinical outcome. Clinical data were obtained from the records of the patients provided by the database of the Gynaecological Cancer Unit at the Royal Adelaide Hospital. Paraffin-embedded tissues of 45 cases were examined using three techniques. Her2 positive rate was 40%. About 13% was strongly positive by all three methods. About 67% Her2 positive patients had advanced-stage disease. Relapse rate was 61% (P = 0.6). Stages I and II had a better survival with negative receptor. Age and stage were major prognostic variables in Cox analysis. Marker status did not reach statistical significance in overall survival (OS) and relapse-free survival (RFS), but had a hazard ratio (HR) of 1.5 in RFS. Five-year OS with Her2 negative was 39%. HR was 0.97 (95% CI 0.46-2.1). RFS was 39% and HR was 1.4 (95% CI 0.65-2.9). The three methods have strong correlation. IHC, 3+ positive cases should be regarded as exhibiting evidence of gene amplification and do not require further testing. Equivocal results require further testing by CISH or PCR. Age and stage are strong prognostic variables and receptor status has a HR of 1.5 in RFS. The therapeutic role of Trastuzumab should be tested in clinical trial setting.
Assuntos
Receptor ErbB-2/metabolismo , Neoplasias Uterinas/metabolismo , Neoplasias Uterinas/patologia , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Hibridização In Situ , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Reação em Cadeia da Polimerase , Proto-Oncogene Mas , Receptor ErbB-2/genética , Taxa de Sobrevida , Neoplasias Uterinas/genéticaRESUMO
Chronic myeloid leukemia (cml) is a myeloproliferative disorder whose therapy has changed dramatically since the late 1990s. With the introduction of the tyrosine kinase inhibitor (tki) imatinib mesylate, the treatment outcomes for patients with cml have improved markedly, and hematopoietic stem-cell transplantation is no longer routinely offered as first-line therapy for most patients in chronic phase.However, resistance to tki therapy is increasingly being recognized, and alternative therapy is needed for this group of patients. In addition, the development of models predicting response to tki therapy is desired, so that appropriate treatment strategies can be used for individual patients. The present report serves to outline the approach to the treatment of cml in British Columbia and to highlight areas of ongoing research.
RESUMO
Laying hens housed in free-range systems have access to an outdoor range, and individual hens within a flock differ in their ranging behaviour. Whether there is a link between ranging and laying hen welfare remains unclear. We analysed the relationships between ranging by individual hens on a commercial free-range layer farm and behavioural, physiological and health measures of animal welfare. We hypothesised that hens that access the range more will be (1) less fearful in general and in response to novelty and humans, (2) have better health in terms of physical body condition and (3) have a reduced physiological stress response to behavioural tests of fear and health assessments than hens that use the range less. Using radio frequency identification tracking across two flocks, we recorded individual hens' frequency, duration and consistency of ranging. We also assessed how far hens ventured into the range based on three zones: 0 to 2.4, 2.4 to 11.4 or >11.4 m from the shed. We assessed hen welfare using a variety of measures including: tonic immobility, open field, novel object, human approach, and human avoidance (HAV) behavioural tests; stress-induced plasma corticosterone response and faecal glucocorticoid metabolites; live weight, comb colour, and beak, plumage, footpad, and keel bone condition. Range use was positively correlated with plasma corticosterone response, faecal glucocorticoid metabolites, and greater flight distance during HAV. Hens that used the range more, moved towards rather than away from the novel object more often than hens that ranged less. Distance ranged from the shed was significantly associated with comb colour and beak condition, in that hens with darker combs and more intact beaks ranged further. Overall the findings suggest that there is no strong link between outdoor range usage and laying hen welfare. Alternatively, it may be that hens that differed in their ranging behaviour showed few differences in measures of welfare because free-range systems provide hens with adequate choice to cope with their environment. Further research into the relationship between individual range access and welfare is needed to test this possibility.