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1.
Front Oncol ; 12: 891850, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36052232

RESUMO

Aim: This study investigated the changes in health-related quality of life from diagnosis to 1 year after diagnosis in breast cancer (BC) patients and the influence of clinical, psychological, and sociodemographic variables. An additional aim was to explore the mediating and moderating effects of resilience on changes in health-related quality of life. Methods: A longitudinal population-based study was conducted in southern Sweden. Newly diagnosed BC patients filled in measures of health-related quality of life, resilience, and sociodemographic variables at diagnosis (N = 980) and 1 year post-diagnosis (N = 780). Clinical variables were extracted from the Swedish national breast cancer quality registry. Mixed-model analyses were performed. Results: Most health-related quality of life outcomes declined from diagnosis to 1 year post-diagnosis. Role limitations due to emotional problems remained the same, whereas mental health improved. Lower health-related quality of life outcomes were associated with symptomatic detection and axillary dissection. Patients with a higher TNM stage and histologic grade and estrogen receptor (ER)-negative and human epidermal growth factor 2 (HER2)-positive status, who received chemotherapy, antibody therapy, or bisphosphonate therapy, had a steeper decline in outcomes. Changes in resilience were positively associated with all outcomes but did not mediate or moderate changes in any. Resilience at baseline moderated changes in bodily pain, vitality, and mental health, with higher baseline resilience being associated with a steeper decline, possibly due to floor or ceiling effects. Patients with lower socioeconomic status, educational level, and older age had a lower health-related quality of life. Conclusion: Physical health-related quality of life among breast cancer patients declined 1 year post-diagnosis, whereas mental health-related quality of life improved. Low resilient patients may be especially vulnerable at diagnosis. Biopsychosocial assessment at diagnosis can help identify patients who may require additional support. A multidimensional treatment plan should be started early to help overcome the problems in everyday activities.

2.
Cancers (Basel) ; 13(9)2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-34066499

RESUMO

Psychological resilience is considered a major protective psychological mechanism that enables a person to successfully handle significant adversities, e.g., a cancer diagnosis. Higher levels of resilience have been associated with higher levels of health-related quality of life (HRQoL) in breast cancer (BC) patients, but research examining the longitudinal process of resilience is limited. The aim of this population-based longitudinal study was to investigate resilience and HRQoL from diagnosis to one year later in 418 Swedish women with primary BC. Resilience was measured with the Connor-Davidson Resilience Scale 25, and HRQoL was measured with the Short Form Health Survey. The participants responded to questions regarding demographic and study-specific variables. Clinicopathological variables were collected from the Swedish National Quality Register for Breast Cancer. The mean score for resilience was 70.6 (standard deviation, SD = 13.0) at diagnosis and 68.9 (SD = 14.0) one year later, p < 0.001. The level of trust in the treatment and financial situation demonstrated the greatest association with the change in resilience levels. No oncological treatment modality was associated with a change in resilience levels. HRQoL decreased over time in the cohort. Resilience was positively associated with HRQoL at one year post diagnosis, which demonstrates that resilience is an important factor in maintaining HRQoL.

3.
Proteomics Clin Appl ; 15(2-3): e2000025, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33580906

RESUMO

PURPOSE: Improved early diagnosis and determination of aggressiveness of prostate cancer (PC) is important to select suitable treatment options and to decrease over-treatment. The conventional marker is total prostate specific antigen (PSA) levels in blood, but lacks specificity and ability to accurately discriminate indolent from aggressive disease. EXPERIMENTAL DESIGN: In this study, we sought to identify a serum biomarker signature associated with metastatic PC. We measured 157 analytes in 363 serum samples from healthy subjects, patients with non-metastatic PC and patients with metastatic PC, using a recombinant antibody microarray. RESULTS: A signature consisting of 69 proteins differentiating metastatic PC patients from healthy controls was identified. CONCLUSIONS AND CLINICAL RELEVANCE: The clinical value of this biomarker signature requires validation in larger independent patient cohorts before providing a new prospect for detection of metastatic PC.


Assuntos
Sobretratamento
4.
Nanomaterials (Basel) ; 11(1)2021 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-33467141

RESUMO

Fluorescence-based detection assays play an essential role in the life sciences and medicine. To offer better detection sensitivity and lower limits of detection (LOD), there is a growing need for novel platforms with an improved readout capacity. In this context, substrates containing semiconductor nanowires may offer significant advantages, due to their proven light-emission enhancing, waveguiding properties, and increased surface area. To demonstrate and evaluate the potential of such nanowires in the context of diagnostic assays, we have in this work adopted a well-established single-chain fragment antibody-based assay, based on a protocol previously designed for biomarker detection using planar microarrays, to freestanding, SiO2-coated gallium phosphide nanowires. The assay was used for the detection of protein biomarkers in highly complex human serum at high dilution. The signal quality was quantified and compared with results obtained on conventional flat silicon and plastic substrates used in the established microarray applications. Our results show that using the nanowire-sensor platform in combination with conventional readout methods, improves the signal intensity, contrast, and signal-to-noise by more than one order of magnitude compared to flat surfaces. The results confirm the potential of lightguiding nanowires for signal enhancement and their capacity to improve the LOD of standard diagnostic assays.

5.
Sci Rep ; 6: 24391, 2016 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-27087644

RESUMO

Helicobacter pylori is an important human pathogen and a common cause of peptic ulcers and gastric cancer. Despite H. pylori provoking strong innate and adaptive immune responses, the bacterium is able to successfully establish long-term infections. Vitronectin (Vn), a component of both the extracellular matrix and plasma, is involved in many physiological processes, including regulation of the complement system. The aim of this study was to define a receptor in H. pylori that binds Vn and determine the significance of the interaction for virulence. Surprisingly, by using proteomics, we found that the hydrogen peroxide-neutralizing enzyme catalase KatA is a major Vn-binding protein. Deletion of the katA gene in three different strains resulted in impaired binding of Vn. Recombinant KatA was generated and shown to bind with high affinity to a region between heparin-binding domain 2 and 3 of Vn that differs from previously characterised bacterial binding sites on the molecule. In terms of function, KatA protected H. pylori from complement-mediated killing in a Vn-dependent manner. Taken together, the virulence factor KatA is a Vn-binding protein that moonlights on the surface of H. pylori to promote bacterial evasion of host innate immunity.


Assuntos
Proteínas de Bactérias/metabolismo , Catalase/metabolismo , Proteínas do Sistema Complemento/metabolismo , Helicobacter pylori/enzimologia , Fatores de Virulência/metabolismo , Vitronectina/metabolismo , Proteínas de Bactérias/genética , Catalase/genética , Deleção de Genes , Helicobacter pylori/imunologia , Evasão da Resposta Imune , Imunidade Inata , Ligação Proteica , Virulência , Fatores de Virulência/química , Vitronectina/química
6.
Nucleic Acids Res ; 42(13): 8516-26, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24990370

RESUMO

Clustered regularly interspaced short palindromic repeats (CRISPR), in combination with CRISPR associated (cas) genes, constitute CRISPR-Cas bacterial adaptive immune systems. To generate immunity, these systems acquire short sequences of nucleic acids from foreign invaders and incorporate these into their CRISPR arrays as spacers. This adaptation process is the least characterized step in CRISPR-Cas immunity. Here, we used Pectobacterium atrosepticum to investigate adaptation in Type I-F CRISPR-Cas systems. Pre-existing spacers that matched plasmids stimulated hyperactive primed acquisition and resulted in the incorporation of up to nine new spacers across all three native CRISPR arrays. Endogenous expression of the cas genes was sufficient, yet required, for priming. The new spacers inhibited conjugation and transformation, and interference was enhanced with increasing numbers of new spacers. We analyzed ∼ 350 new spacers acquired in priming events and identified a 5'-protospacer-GG-3' protospacer adjacent motif. In contrast to priming in Type I-E systems, new spacers matched either plasmid strand and a biased distribution, including clustering near the primed protospacer, suggested a bi-directional translocation model for the Cas1:Cas2-3 adaptation machinery. Taken together these results indicate priming adaptation occurs in different CRISPR-Cas systems, that it can be highly active in wild-type strains and that the underlying mechanisms vary.


Assuntos
Sistemas CRISPR-Cas , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Proteínas Associadas a CRISPR/genética , Conjugação Genética , Pectobacterium/genética , Plasmídeos/genética , Transformação Genética
7.
Annu Rev Virol ; 1(1): 307-31, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26958724

RESUMO

Bacteriophages (phages) specifically infect bacteria and are the most abundant biological entities on Earth. The constant exposure to phage infection imposes a strong selective pressure on bacteria to develop viral resistance strategies that promote prokaryotic survival. Thus, this parasite-host relationship results in an evolutionary arms race of adaptation and counteradaptation between the interacting partners. The evolutionary outcome is a spectrum of remarkable strategies used by the bacteria and phages as they attempt to coexist. These approaches include adsorption inhibition, injection blocking, abortive infection, toxin-antitoxin, and CRISPR-Cas systems. In this review, we highlight the diverse and complementary antiphage systems in bacteria, as well as the evasion mechanisms used by phages to escape these resistance strategies.

8.
Biochem Soc Trans ; 41(6): 1468-74, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24256239

RESUMO

CRISPR (clustered regularly interspaced short palindromic repeats) arrays and Cas (CRISPR-associated) proteins confer acquired resistance against mobile genetic elements in a wide range of bacteria and archaea. The phytopathogen Pectobacterium atrosepticum SCRI1043 encodes a single subtype I-F CRISPR system, which is composed of three CRISPR arrays and the cas operon encoding Cas1, Cas3 (a Cas2-Cas3 fusion), Csy1, Csy2, Csy3 and Cas6f (Csy4). The CRISPR arrays are transcribed into pre-crRNA (CRISPR RNA) and then processed by Cas6f to generate crRNAs. Furthermore, the formation of Cas protein complexes has been implicated in both the interference and acquisition stages of defence. In the present paper, we discuss the development of tightly controlled 'programmable' CRISPR arrays as tools to investigate CRISPR-Cas function and the effects of chromosomal targeting. Finally, we address how chromosomal targeting by CRISPR-Cas can cause large-scale genome deletions, which can ultimately influence bacterial evolution and pathogenicity.


Assuntos
Proteínas Associadas a CRISPR/biossíntese , Sistemas CRISPR-Cas/fisiologia , Ilhas Genômicas/genética , Pectobacterium/genética , Pectobacterium/metabolismo , RNA Bacteriano/metabolismo , Proteínas Associadas a CRISPR/genética , Proteínas Associadas a CRISPR/metabolismo , Sistemas CRISPR-Cas/imunologia , Pectobacterium/imunologia , RNA Bacteriano/genética
9.
PLoS Genet ; 9(4): e1003454, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23637624

RESUMO

In prokaryotes, clustered regularly interspaced short palindromic repeats (CRISPRs) and their associated (Cas) proteins constitute a defence system against bacteriophages and plasmids. CRISPR/Cas systems acquire short spacer sequences from foreign genetic elements and incorporate these into their CRISPR arrays, generating a memory of past invaders. Defence is provided by short non-coding RNAs that guide Cas proteins to cleave complementary nucleic acids. While most spacers are acquired from phages and plasmids, there are examples of spacers that match genes elsewhere in the host bacterial chromosome. In Pectobacterium atrosepticum the type I-F CRISPR/Cas system has acquired a self-complementary spacer that perfectly matches a protospacer target in a horizontally acquired island (HAI2) involved in plant pathogenicity. Given the paucity of experimental data about CRISPR/Cas-mediated chromosomal targeting, we examined this process by developing a tightly controlled system. Chromosomal targeting was highly toxic via targeting of DNA and resulted in growth inhibition and cellular filamentation. The toxic phenotype was avoided by mutations in the cas operon, the CRISPR repeats, the protospacer target, and protospacer-adjacent motif (PAM) beside the target. Indeed, the natural self-targeting spacer was non-toxic due to a single nucleotide mutation adjacent to the target in the PAM sequence. Furthermore, we show that chromosomal targeting can result in large-scale genomic alterations, including the remodelling or deletion of entire pre-existing pathogenicity islands. These features can be engineered for the targeted deletion of large regions of bacterial chromosomes. In conclusion, in DNA-targeting CRISPR/Cas systems, chromosomal interference is deleterious by causing DNA damage and providing a strong selective pressure for genome alterations, which may have consequences for bacterial evolution and pathogenicity.


Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Ilhas Genômicas , Sistemas CRISPR-Cas , Genoma Bacteriano , Plasmídeos
10.
PLoS One ; 7(12): e49549, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23226499

RESUMO

Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) and their associated proteins (Cas; CRISPR associated) are a bacterial defense mechanism against extra-chromosomal elements. CRISPR/Cas systems are distinct from other known defense mechanisms insofar as they provide acquired and heritable immunity. Resistance is accomplished in multiple stages in which the Cas proteins provide the enzymatic machinery. Importantly, subtype-specific proteins have been shown to form complexes in combination with small RNAs, which enable sequence-specific targeting of foreign nucleic acids. We used Pectobacterium atrosepticum, a plant pathogen that causes soft-rot and blackleg disease in potato, to investigate protein-protein interactions and complex formation in the subtype I-F CRISPR/Cas system. The P. atrosepticum CRISPR/Cas system encodes six proteins: Cas1, Cas3, and the four subtype specific proteins Csy1, Csy2, Csy3 and Cas6f (Csy4). Using co-purification followed by mass spectrometry as well as directed co-immunoprecipitation we have demonstrated complex formation by the Csy1-3 and Cas6f proteins, and determined details about the architecture of that complex. Cas3 was also shown to co-purify all four subtype-specific proteins, consistent with its role in targeting. Furthermore, our results show that the subtype I-F Cas1 and Cas3 (a Cas2-Cas3 hybrid) proteins interact, suggesting a protein complex for adaptation and a role for subtype I-F Cas3 proteins in both the adaptation and interference steps of the CRISPR/Cas mechanism.


Assuntos
Proteínas de Bactérias/metabolismo , Pectobacterium/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/isolamento & purificação , Sequência de Bases , Western Blotting , Cromatografia de Afinidade , Primers do DNA , Vetores Genéticos , Imunoprecipitação , Espectrometria de Massas , Dados de Sequência Molecular , Oligodesoxirribonucleotídeos , Ligação Proteica , Homologia de Sequência de Aminoácidos
11.
Viruses ; 4(10): 2291-311, 2012 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-23202464

RESUMO

Phages are the most abundant biological entities on earth and pose a constant challenge to their bacterial hosts. Thus, bacteria have evolved numerous 'innate' mechanisms of defense against phage, such as abortive infection or restriction/modification systems. In contrast, the clustered regularly interspaced short palindromic repeats (CRISPR) systems provide acquired, yet heritable, sequence-specific 'adaptive' immunity against phage and other horizontally-acquired elements, such as plasmids. Resistance is acquired following viral infection or plasmid uptake when a short sequence of the foreign genome is added to the CRISPR array. CRISPRs are then transcribed and processed, generally by CRISPR associated (Cas) proteins, into short interfering RNAs (crRNAs), which form part of a ribonucleoprotein complex. This complex guides the crRNA to the complementary invading nucleic acid and targets this for degradation. Recently, there have been rapid advances in our understanding of CRISPR/Cas systems. In this review, we will present the current model(s) of the molecular events involved in both the acquisition of immunity and interference stages and will also address recent progress in our knowledge of the regulation of CRISPR/Cas systems.


Assuntos
Bacteriófagos/patogenicidade , Endodesoxirribonucleases/metabolismo , Escherichia coli/virologia , Regulação Bacteriana da Expressão Gênica , Sequências Repetidas Invertidas , Adaptação Biológica , Bacteriófagos/genética , Bacteriófagos/metabolismo , Proteínas Associadas a CRISPR , Endodesoxirribonucleases/genética , Ativação Enzimática , Escherichia coli/enzimologia , Escherichia coli/genética , Proteínas de Escherichia coli , Plasmídeos/genética , Plasmídeos/metabolismo , Mapeamento de Interação de Proteínas , Interferência de RNA , Processamento Pós-Transcricional do RNA , RNA Bacteriano/genética , RNA Bacteriano/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Especificidade da Espécie
12.
RNA Biol ; 8(3): 517-28, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21519197

RESUMO

CRISPR/Cas systems provide bacteria and archaea with small RNA-based adaptive immunity against foreign elements such as phages and plasmids. An important step in the resistance mechanism involves the generation of small guide RNAs (crRNAs) that, in combination with Cas proteins, recognize and inhibit foreign nucleic acids in a sequence specific manner. The generation of crRNAs requires processing of the primary CRISPR RNA by an endoribonuclease. In this study we have characterized the Ypest subtype CRISPR/Cas system in the plant pathogen Pectobacterium atrosepticum. We analyse the transcription of the cas genes and the 3 CRISPR arrays. The cas genes are expressed as an operon and all three CRISPR arrays are transcribed and processed into small RNAs. The Csy4 protein was identified as responsible for processing of CRISPR RNA in vivo and in vitro into crRNAs and appears to interact with itself in the absence of other Cas proteins. This study furthers our understanding of the CRISPR/Cas mechanism by providing the first in vivo evidence that the CRISPR endoribonuclease Csy4 generates crRNAs in its native host and characterizes the operonic transcription of the cas cluster.


Assuntos
Proteínas de Bactérias/genética , Pectobacterium/genética , Processamento Pós-Transcricional do RNA , RNA Bacteriano/metabolismo , Proteínas de Bactérias/metabolismo , Sequência de Bases , Dados de Sequência Molecular , Pectobacterium/metabolismo
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