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1.
Z Gerontol Geriatr ; 57(2): 97-102, 2024 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-38276996

RESUMEN

BACKGROUND: The dual nature of socio-technical systems requires new design paradigms that go beyond conventional informatic instrumental approaches. With the realization that digital applications change social practice but also that social influences affect design principles of digital technologies, design principles must be oriented towards real-world practices and thus towards situated forms of appropriation of the intended user groups. This is achieved with newer approaches of practice-based design, which are based on ethnography-based and participatory design principles and share a number of basic assumptions of participatory approaches in gerontology. OBJECTIVE: The aim of the article is to explain basic approaches of practice-based design from the field of socio-informatics and to relate them to participatory approaches in gerontology. MATERIAL AND METHODS: The article develops an interdisciplinary perspective on the design of socio-technical systems. RESULTS AND DISCUSSION: Interdisciplinary connecting lines are listed that can inspire current development projects, thus opening a corridor for efforts in the further development of analytical, conceptual and methodological perspectives. The discussion provides interdisciplinary approaches for the conception, design and appropriation of IT applications and infrastructures for and with older people on the basis of participatory and qualitative empirical approaches. The aim is to align IT design more closely with situated practices, sociocultural contexts and sense-making processes of older people.


Asunto(s)
Geriatría , Humanos , Anciano
2.
Nature ; 541(7638): 546-549, 2017 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-27906161

RESUMEN

In bacteria, ribosomes stalled on truncated mRNAs that lack a stop codon are rescued by the transfer-messenger RNA (tmRNA), alternative rescue factor A (ArfA) or ArfB systems. Although tmRNA-ribosome and ArfB-ribosome structures have been determined, how ArfA recognizes the presence of truncated mRNAs and recruits the canonical termination release factor RF2 to rescue the stalled ribosomes is unclear. Here we present a cryo-electron microscopy reconstruction of the Escherichia coli 70S ribosome stalled on a truncated mRNA in the presence of ArfA and RF2. The structure shows that the C terminus of ArfA binds within the mRNA entry channel on the small ribosomal subunit, and explains how ArfA distinguishes between ribosomes that bear truncated or full-length mRNAs. The N terminus of ArfA establishes several interactions with the decoding domain of RF2, and this finding illustrates how ArfA recruits RF2 to the stalled ribosome. Furthermore, ArfA is shown to stabilize a unique conformation of the switch loop of RF2, which mimics the canonical translation termination state by directing the catalytically important GGQ motif within domain 3 of RF2 towards the peptidyl-transferase centre of the ribosome. Thus, our structure reveals not only how ArfA recruits RF2 to the ribosome but also how it promotes an active conformation of RF2 to enable translation termination in the absence of a stop codon.


Asunto(s)
Codón de Terminación , Microscopía por Crioelectrón , Proteínas de Escherichia coli/química , Terminación de la Cadena Péptídica Traduccional , Factores de Terminación de Péptidos/química , ARN Mensajero/genética , ARN Mensajero/metabolismo , Proteínas de Unión al ARN/química , Ribosomas/metabolismo , Escherichia coli/química , Escherichia coli/genética , Escherichia coli/ultraestructura , Proteínas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/ultraestructura , Modelos Moleculares , Factores de Terminación de Péptidos/metabolismo , Factores de Terminación de Péptidos/ultraestructura , Unión Proteica , Conformación Proteica , Estabilidad Proteica , Proteínas de Unión al ARN/metabolismo , Proteínas de Unión al ARN/ultraestructura , Ribosomas/química , Ribosomas/ultraestructura
3.
J Med Internet Res ; 25: e45750, 2023 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-37459177

RESUMEN

BACKGROUND: Participatory Design (PD), albeit an established approach in User-Centered Design, comes with specific challenges when working with older adults as research participants. Addressing these challenges relates to the reflection and negotiation of the positionalities of the researchers and research participants and includes various acts of giving and receiving help. During the COVID-19 pandemic, facets of positionalities and (mutual) care became particularly evident in qualitative and participatory research settings. OBJECTIVE: The aim of this paper was to systematically analyze care practices of participatory (design) research, which are to different extents practices of the latter. Using a multiyear PD project with older people that had to take place remotely over many months, we specify different practices of care; how they relate to collaborative work in the design project; and represent foundational practices for sustainable, long-term co-design. Our research questions were "How can digitally-mediated PD work during COVID-19 and can we understand such digital PD as 'care'?" METHODS: Our data comes from the Joint Programming Initiative "More Years, Better Lives" (JPI MYBL), a European Union project that aims to promote digital literacy and technology appropriation among older adults in domestic settings. It targeted the cocreation, by older adults and university researchers, of a mobile demo kit website with cocreated resources, aimed at improving the understanding of use options of digital tools. Through a series of workshops, a range of current IT products was explored by a group of 21 older adults, which served as the basis for joint cocreative work on generating design ideas and prototypes. We reflect on the PD process and examine how the actors enact and manifest care. RESULTS: The use of digital technology allowed the participatory project to continue during the COVID-19 pandemic and accentuated the digital skills of older adults and the improvement of digital literacy as part of "care." We provide empirically based evidence of PD with older adults developing digital literacy and sensitizing concepts, based on the notion of care by Tronto for differentiating aspects and processes of care. The data suggest that it is not enough to focus solely on the technologies and how they are used; it is also necessary to focus on the social structures in which help is available and in which technologies offer opportunities to do care work. CONCLUSIONS: We document that the cocreation of different digital media tools can be used to provide a community with mutual care. Our study demonstrates how research participants effectively enact different forms of care and how such "care" is a necessary basis for a genuinely participatory approach, which became especially meaningful as a form of support during COVID-19. We reflect on how notions of "care" and "caring" that were central to the pandemic response are also central to PD.


Asunto(s)
COVID-19 , Telemedicina , Anciano , Humanos , COVID-19/epidemiología , Tecnología Digital , Internet , Negociación , Pandemias , Investigación Participativa Basada en la Comunidad , Envejecimiento
4.
Toxicol Appl Pharmacol ; 436: 115862, 2022 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-34998853

RESUMEN

While a considerable body of literature has characterized the clinical features induced by organophosphate pesticides, the field lacks scrutiny into cardio-respiratory changes in different phases of poisoning. Herein, we evaluated the impact of chlorpyrifos (CPF) and its active metabolite chlorpyrifos-oxon (CPO) on the cardiorespiratory system during acute and subacute phases of poisoning using an in situ experimental rodent model. CPF (30 mg/kg) was injected intraperitoneally to rats beforehand (24 h) whereas CPO (15 mg/kg) was added into the perfusate reservoir to evaluate the effects on the motor outputs throughout the three phases of the respiratory cycle: inspiration, post-inspiration and late expiration. Phrenic, recurrent laryngeal (RLN) and thoracic sympathetic nerve activity (tSNA) were recorded. Heart rate was derived from the electrocardiogram (ECG) and the baro- and chemo-reflexes tested. CPF and CPO led to a time-dependent change in cardiorespiratory motor outputs. In the acute phase, the CPO induced bradypnea, transiently reduced the inspiratory time (TI), and increased the amplitude of phrenic. Post-inspiratory (PI) discharge recorded from the RLN was progressively reduced while tSNA was increased. CPO significantly depressed the chemoreflex but had no effect on baroreflex. During subacute phase, CPF prolongated TI with no effect on respiratory rate. Both the RLN PI discharge, the chemoreflex and the baroreflex sympathetic gain were reduced. In addition, both CPF and CPO shifted the cardiac sympatho-vagal balance towards sympathetic dominance. Our data show that different phases of poisoning are associated with specific changes in the cardio-respiratory system and might therefore demand distinct approaches by health care providers.


Asunto(s)
Barorreflejo/efectos de los fármacos , Cloropirifos/efectos adversos , Frecuencia Cardíaca/efectos de los fármacos , Corazón/efectos de los fármacos , Sistema Respiratorio/efectos de los fármacos , Animales , Cloropirifos/análogos & derivados , Inhibidores de la Colinesterasa/efectos adversos , Insecticidas/efectos adversos , Masculino , Ratas , Ratas Wistar , Frecuencia Respiratoria/efectos de los fármacos
5.
BMC Public Health ; 22(1): 1379, 2022 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-35854283

RESUMEN

BACKGROUND: Current incidence estimates of SARS-CoV-2 in Germany rely to a large extent on case notifications. However, the large number of mild or asymptomatic infections is likely to result in underestimation. Population-based studies can provide valid estimates of the SARS-CoV-2 incidence and thus support health authorities to monitor the epidemiological situation and to initiate, maintain, strengthen or relax effective countermeasures. METHODS: This study was conducted in Cologne, Germany. Six-thousand randomly drawn Cologne residents, 18 years of age or older, were contacted by mail in March 2021. Study envelopes contained a kit for self-administered saliva sample and access details to a questionnaire on sociodemographic characteristics, previous positive SARS-CoV-2 RT-qPCR and completed COVID-19 vaccinations. Participants were again invited for a second round in June 2021, while those who declined participation were replaced by additional randomly drawn Cologne residents in order to reach a total of 6000 potential participants again. The saliva samples were sent to the laboratory by mail and tested for SARS-CoV-2 using RT-qPCR. The incidence estimates were adjusted for sensitivity and specificity of the test procedure and compared with the official numbers of new SARS-CoV-2 cases in the adult Cologne population. RESULTS: The first surveillance round in March 2021 (response rate: 34.08%, N = 2045) showed a SARS-CoV-2 seven-day incidence of 85 cases per 100,000 adult Cologne residents (95% CI: 9 to 319). In the same period, the officially registered cases were 125 per 100,000. The second surveillance round in June 2021 (response rate: 36.53%, N = 2192) showed a seven-day incidence of 27 per 100,000 adult Cologne residents (95% CI: 1 to 142), while the official figures for newly registered SARS-CoV-2 cases in the same period were 15 per 100,000. CONCLUSIONS: The incidence estimates do not indicate relevant underestimation of new SARS-CoV-2 infections based on case notification. Regular use of the surveillance method developed here may nevertheless complement the efforts of the health authorities to assess the epidemiological situation. TRIAL REGISTRATION: DRKS.de, German Clinical Trials Register (DRKS), Identifier: DRKS00024046 , Registered on 25 February 2021.


Asunto(s)
COVID-19 , Adolescente , Adulto , Humanos , Estudios de Cohortes , COVID-19/diagnóstico , COVID-19/epidemiología , COVID-19/prevención & control , Incidencia , Estudios Prospectivos , SARS-CoV-2
6.
Trends Biochem Sci ; 42(8): 669-680, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28629612

RESUMEN

Ribosomes that translate mRNAs lacking stop codons become stalled at the 3' end of the mRNA. Recycling of these stalled ribosomes is essential for cell viability. In bacteria three ribosome rescue systems have been identified so far, with the most ubiquitous and best characterized being the trans-translation system mediated by transfer-messenger RNA (tmRNA) and small protein B (SmpB). The two additional rescue systems present in some bacteria employ alternative rescue factor (Arf) A and release factor (RF) 2 or ArfB. Recent structures have revealed how ArfA mediates ribosome rescue by recruiting the canonical termination factor RF2 to ribosomes stalled on truncated mRNAs. This now provides us with the opportunity to compare and contrast the available structures of all three bacterial ribosome rescue systems.


Asunto(s)
Bacterias/metabolismo , Ribosomas/metabolismo , Bacterias/genética , Conformación de Ácido Nucleico , Ribosomas/química
7.
Biol Chem ; 402(11): 1465-1478, 2021 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-34085493

RESUMEN

Synthetically sulfated hyaluronan derivatives were shown to facilitate osteogenic differentiation of human bone marrow stromal cells (hBMSC) by application in solution or incorporated in thin collagen-based coatings. In the presented study, using a biomimetic three-dimensional (3D) cell culture model based on fibrillary collagen I (3D Col matrix), we asked on the impact of binding mode of low sulfated hyaluronan (sHA) in terms of adsorptive and covalent binding on osteogenic differentiation of hBMSC. Both binding modes of sHA induced osteogenic differentiation. Although for adsorptive binding of sHA a strong intracellular uptake of sHA was observed, implicating an intracellular mode of action, covalent binding of sHA to the 3D matrix induced also intense osteoinductive effects pointing towards an extracellular mode of action of sHA in osteogenic differentiation. In summary, the results emphasize the relevance of fibrillary 3D Col matrices as a model to study hBMSC differentiation in vitro in a physiological-like environment and that sHA can display dose-dependent osteoinductive effects in dependence on presentation mode in cell culture scaffolds.


Asunto(s)
Colágeno/farmacología , Ácido Hialurónico/farmacología , Células Madre Mesenquimatosas/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Sulfatos/farmacología , Sitios de Unión/efectos de los fármacos , Colágeno/química , Humanos , Ácido Hialurónico/química , Células Madre Mesenquimatosas/metabolismo , Sulfatos/química
8.
Biol Chem ; 402(11): 1427-1440, 2021 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-34472763

RESUMEN

Glycosaminoglycans (GAGs) are essential functional components of the extracellular matrix (ECM). Artificial GAGs like sulfated hyaluronan (sHA) exhibit pro-osteogenic properties and boost healing processes. Hence, they are of high interest for supporting bone regeneration and wound healing. Although sulfated GAGs (sGAGs) appear intracellularly, the knowledge about intracellular effects and putative interaction partners is scarce. Here we used an affinity-purification mass spectrometry-based (AP-MS) approach to identify novel and particularly intracellular sGAG-interacting proteins in human bone marrow stromal cells (hBMSC). Overall, 477 proteins were found interacting with at least one of four distinct sGAGs. Enrichment analysis for protein localization showed that mainly intracellular and cell-associated interacting proteins were identified. The interaction of sGAG with α2-macroglobulin receptor-associated protein (LRPAP1), exportin-1 (XPO1), and serine protease HTRA1 (HTRA1) was confirmed in reverse assays. Consecutive pathway and cluster analysis led to the identification of biological processes, namely processes involving binding and processing of nucleic acids, LRP1-dependent endocytosis, and exosome formation. Respecting the preferentially intracellular localization of sGAG in vesicle-like structures, also the interaction data indicate sGAG-specific modulation of vesicle-based transport processes. By identifying many sGAG-specific interacting proteins, our data provide a resource for upcoming studies aimed at molecular mechanisms and understanding of sGAG cellular effects.


Asunto(s)
Glicosaminoglicanos/metabolismo , Serina Peptidasa A1 que Requiere Temperaturas Altas/metabolismo , Carioferinas/metabolismo , Proteína Asociada a Proteínas Relacionadas con Receptor de LDL/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , Células Cultivadas , Cromatografía Liquida , Glicosaminoglicanos/química , Serina Peptidasa A1 que Requiere Temperaturas Altas/química , Serina Peptidasa A1 que Requiere Temperaturas Altas/aislamiento & purificación , Humanos , Carioferinas/química , Carioferinas/aislamiento & purificación , Proteína Asociada a Proteínas Relacionadas con Receptor de LDL/química , Proteína Asociada a Proteínas Relacionadas con Receptor de LDL/aislamiento & purificación , Células Madre Mesenquimatosas/química , Células Madre Mesenquimatosas/metabolismo , Receptores Citoplasmáticos y Nucleares/química , Receptores Citoplasmáticos y Nucleares/aislamiento & purificación , Espectrometría de Masas en Tándem , Proteína Exportina 1
9.
BMC Public Health ; 21(1): 1295, 2021 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-34215236

RESUMEN

BACKGROUND: Surveillance strategies are critical to cope with the current SARS-CoV-2 pandemic and to evaluate, as well as adjust government-imposed countermeasures. Incidence estimates are widely based on laboratory confirmed cases reported by health authorities. Prevalence and incidence data of SARS-CoV-2 is still scarce, along with demographic and behavioural factors associated with infection risk. METHODS: The Cologne Corona Surveillance Study will be conducted in the City of Cologne, which is the fourth-largest city in Germany with a population of approximately 1.1 million. Researchers will apply self-sampling surveillance to a rolling cohort of Cologne residents. Random samples of 6000 Cologne residents 18 years of age and older will be drawn from the registration office. Upon receiving the information and saliva sample kit, participants will be asked to fill out a questionnaire online or via phone, sign written informed consent, and send back written consent, as well as saliva sample. The saliva samples will be tested for SARS-CoV-2 by reverse PCR. The questionnaire will be administered to gather information about personal characteristics such as health status and risks. A second round of testing will take place 6 weeks after the first. DISCUSSION: Self-administered saliva sampling proved to be a legitimate and feasible alternative to nasopharyngeal swabs taken by health professionals. However, it is unclear whether the targeted response rate of 40% can be achieved and whether the results are representative of the population. TRIAL REGISTRATION: DRKS.de, German Clinical Trials Register (DRKS), Identifier: DRKS00024046 , Registered on 25 February 2021.


Asunto(s)
COVID-19 , SARS-CoV-2 , Adolescente , Adulto , Estudios de Cohortes , Humanos , Estudios Prospectivos , Resultado del Tratamiento
10.
Toxicol Appl Pharmacol ; 389: 114879, 2020 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-31931016

RESUMEN

In a previous work we showed that the organophosphate pesticide (OP) chlorpyrifos (CPF) reduces the protective chemoreflex and baroreflex responses in rats. However, whether the antidotes atropine (ATR) and pralidoxime (2-PAM) are capable of restoring these reflex functions remains unexplored. Rats were poisoned with CPF (30 mg.kg-1, i.p.) and one hour after the intoxication, ATR (10 mg.kg-1, i.p.) and 2-PAM (40 mg.kg-1, i.p.) were administrated separately or in combination. Cardiorespiratory parameters were recorded in awake rats 24 h after CPF. Systolic blood pressure (SBP) and heart rate (HR) variability and spontaneous baroreflex sensitivity (sBRS) were derived from undisturbed recordings (30 min), while chemoreflex was assessed through potassium cyanide (KCN) i.v. injections (10, 20, 40, 80 µg/rat). CPF poisoning increased SBP variability and low frequency/high frequency (LF/HF) ratio of the HR variability spectrum, indicating autonomic imbalance with increased cardiac sympathetic tone. sBRS was not changed. Treatment with 2-PAM restored SBP variability, whilst both antidotes increased LF/HF ratio. CPF poisoning reduced the hypertensive, bradycardic and tachypneic chemoreflex responses. Chemoreflex-induced hypertensive response was restored by 2-PAM treatment, while ATR recovered the bradycardic response. Both antidotes restored the chemoreflex tachypneic response. Our data show distinct effects of ATR and 2-PAM on cardiorespiratory parameters affected by OP poisoning. While 2-PAM rescued the chemoreflex hypertensive response, ATR reversed chemoreflex bradycardic dysfunction. Although 2-PAM clinical use is questioned in some countries, our data indicate that summation of effects of both antidotes appears beneficial on the cardiorespiratory system and peripheral chemoreflex function.


Asunto(s)
Antídotos/farmacología , Atropina/farmacología , Sistema Cardiovascular/efectos de los fármacos , Cloropirifos/efectos adversos , Intoxicación por Organofosfatos/tratamiento farmacológico , Compuestos de Pralidoxima/farmacología , Sistema Respiratorio/efectos de los fármacos , Animales , Barorreflejo/efectos de los fármacos , Presión Sanguínea/efectos de los fármacos , Bradicardia/tratamiento farmacológico , Inhibidores de la Colinesterasa/efectos adversos , Frecuencia Cardíaca/efectos de los fármacos , Insecticidas/efectos adversos , Masculino , Ratas , Ratas Wistar
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