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1.
Mar Drugs ; 22(2)2024 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-38393064

RESUMEN

This study aimed to investigate the regulation of fucoxanthin (FX) biosynthesis under various nitrogen conditions to optimize FX productivity in Phaeodactylum tricornutum. Apart from light, nitrogen availability significantly affects the FX production of microalgae; however, the underlying mechanism remains unclear. In batch culture, P. tricornutum was cultivated with normal (NN, 0.882 mM sodium nitrate), limited (LN, 0.22 mM), and high (HN, 8.82 mM) initial nitrogen concentrations in f/2 medium. Microalgal growth and photosynthetic pigment production were examined, and day 5 samples were subjected to fucoxanthin-chlorophyll a/c-binding protein (FCP) proteomic and transcriptomic analyses. The result demonstrated that HN promoted FX productivity by extending the exponential growth phase for higher biomass and FX accumulation stage (P1), showing a continuous increase in FX accumulation on day 6. Augmented FX biosynthesis via the upregulation of carotenogenesis could be primarily attributed to enhanced FCP formation in the thylakoid membrane. Key proteins, such as LHC3/4, LHCF8, LHCF5, and LHCF10, and key genes, such as PtPSY, PtPDS, and PtVDE, were upregulated under nitrogen repletion. Finally, the combination of low light and HN prolonged the P1 stage to day 10, resulting in maximal FX productivity to 9.82 ± 0.56 mg/L/day, demonstrating an effective strategy for enhancing FX production in microalgae cultivation.


Asunto(s)
Diatomeas , Microalgas , Xantófilas , Clorofila A , Nitrógeno/metabolismo , Proteómica , Diatomeas/metabolismo
2.
Adv Exp Med Biol ; 1261: 21-27, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33783728

RESUMEN

Cladosiphon (C.) okamuranus, a brown alga endemic to the Nansei Islands, Japan, has been conventionally ingested as food. Nowadays, it is a major aquatic product of the Okinawa Prefecture with an annual production of around 20,000 tons. The life cycle of C. okamuranus comprises the macroscopic sporophyte (algal body) generation and the microscopic gametophyte generation. The germlings in the latter generation can proliferate when floating in seawater. This floating form has been exploited in techniques involved in the commercial production of C. okamuranus seedlings.Brown algae contain fucoxanthin, a carbonyl carotenoid known to have anticancer, anti-obesity, and antidiabetic effect in addition to the anti-oxidation effect. We found that the fucoxanthin content of cultivated floating form of C. okamuranus discoid germlings becomes up to 50 times that of the mature alga. Since the discoid germlings repeatedly grow like microorganisms, although they are large algae, they are utilized to produce fucoxanthin. We optimize the culture conditions by changing the temperature, light intensity, photoperiod, light wavelength, and nutrient salt conditions for optimal fucoxanthin productivity. The cultivation has been successful to industrial plant scale, culminating in the use of 1 ton of cultivating medium.In brown algal cells, fucoxanthin is primarily found bound to the photosynthetic pigment-protein complexes known as fucoxanthin-chlorophyll protein (FCP). Consequently cultivated floating form of C. okamuranus also shows high content of FCP. Isolation and characterization of pigments bound to the FCP were determined precisely, and ultrafast spectroscopies were applied to elucidate the photosynthetic function of fucoxanthin bound to the pigment-protein complexes. This cultivation method has also been applied to the other edible brown algae. We found that the optimal cultivation conditions as well as the yields of fucoxanthin and FCP highly depend on the species.The floating form cultivation was also applied to a large-sized edible green alga, Codium intricatum, which is uniquely producing a carbonyl carotenoid, siphonaxanthin. This has several anti-disease effects and is also a primal photosynthetic pigment which is found bound to photosynthetic antenna complex usually called siphonaxanthin-chlorophyll protein (SCP). We are working on the improvement of productivity, scale-up of production, and development of cultivation technology of new macro algae.


Asunto(s)
Phaeophyceae , Algas Marinas , Carotenoides , Clorofila , Japón
3.
J Biol Chem ; 294(44): 16080-16094, 2019 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-31506296

RESUMEN

Fcp1 is a protein phosphatase that facilitates transcription elongation and termination by dephosphorylating the C-terminal domain of RNA polymerase II. High-throughput genetic screening and gene expression profiling of fcp1 mutants revealed a novel connection to Cdk8, the Mediator complex kinase subunit, and Skn7, a key transcription factor in the oxidative stress response pathway. Briefly, Skn7 was enriched as a regulator of genes whose mRNA levels were altered in fcp1 and cdk8Δ mutants and was required for the suppression of fcp1 mutant growth defects by loss of CDK8 under oxidative stress conditions. Targeted analysis revealed that mutating FCP1 decreased Skn7 mRNA and protein levels as well as its association with target gene promoters but paradoxically increased the mRNA levels of Skn7-dependent oxidative stress-induced genes (TRX2 and TSA1) under basal and induced conditions. The latter was in part recapitulated via chemical inhibition of transcription in WT cells, suggesting that a combination of transcriptional and posttranscriptional effects underscored the increased mRNA levels of TRX2 and TSA1 observed in the fcp1 mutant. Interestingly, loss of CDK8 robustly normalized the mRNA levels of Skn7-dependent genes in the fcp1 mutant background and also increased Skn7 protein levels by preventing its turnover. As such, our work suggested that loss of CDK8 could overcome transcriptional and/or posttranscriptional alterations in the fcp1 mutant through its regulatory effect on Skn7. Furthermore, our work also implicated FCP1 and CDK8 in the broader response to environmental stressors in yeast.


Asunto(s)
Quinasa 8 Dependiente de Ciclina/metabolismo , Proteínas de Unión al ADN/metabolismo , Regulación Fúngica de la Expresión Génica , Estrés Oxidativo , Fosfoproteínas Fosfatasas/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Factores de Transcripción/metabolismo , Quinasa 8 Dependiente de Ciclina/genética , Proteínas de Unión al ADN/genética , Peroxidasas/genética , Peroxidasas/metabolismo , Fosfoproteínas Fosfatasas/genética , Estabilidad Proteica , Saccharomyces cerevisiae , Proteínas de Saccharomyces cerevisiae/genética , Tiorredoxinas/genética , Tiorredoxinas/metabolismo , Factores de Transcripción/genética , Activación Transcripcional
4.
Photosynth Res ; 146(1-3): 189-195, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32114648

RESUMEN

CO2 concentration and temperature for growth of photosynthetic organisms are two important factors to ensure better photosynthetic performance. In this study, we investigated the effects of CO2 concentration and temperature on the photosynthetic performance in a marine centric diatom Chaetoceros gracilis. Cells were grown under four different conditions, namely, at 25 °C with air bubbling, at 25 °C with a supplementation of 3% CO2, at 30 °C with air bubbling, and at 30 °C with the CO2 supplementation. It was found that the growth rate of cells at 30 °C with the CO2 supplementation is faster than those at other three conditions. The pigment compositions of cells grown under the different conditions are altered, and fluorescence spectra measured at 77 K also showed different peak positions. A novel fucoxanthin chlorophyll a/c-binding protein complex is observed in the cells grown at 30 °C with the CO2 supplementation but not in the other three types of cells. Since oxygen-evolving activities of the four types of cells are almost unchanged, it is suggested that the CO2 supplementation and growth temperature are involved in the regulation of photosynthetic light-harvesting apparatus in C. gracilis at different degrees. Based on these observations, we discuss the favorable growth conditions for C. gracilis.


Asunto(s)
Dióxido de Carbono/farmacología , Diatomeas/fisiología , Fotosíntesis/fisiología , Clorofila/análogos & derivados , Clorofila/metabolismo , Clorofila A/metabolismo , Diatomeas/metabolismo , Fluorescencia , Temperatura , Xantófilas/metabolismo
5.
Photosynth Res ; 140(2): 141-149, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30187302

RESUMEN

Diatoms are dominant phytoplankton in aquatic environments and have unique light-harvesting apparatus, fucoxanthin chlorophyll a/c-binding protein (FCP). Diatom photosystem I (PSI) interacts with specific FCPs (FCPI); however, it remains unclear how PSI cores receive excitation energy from FCPI. To analyze the energy transfer dynamics, it is necessary to isolate both PSI cores and PSI-FCPI complexes. In this study, we prepared three PSI complexes, which are PSI-FCPI membrane fragments, detergent-solubilized PSI-FCPI supercomplexes and PSI core-like complexes, from the marine centric diatom, Chaetoceros gracilis, and examined their biochemical properties. Both the PSI-FCPI membrane fragments and supercomplexes showed similar subunit compositions including FCPI, whereas the PSI complexes were devoid of most FCPI subunits. The purity and homogeneity of the two detergent-solubilized PSI preparations were verified by clear-native PAGE and electron microscopy. The difference of pigment contents among the three PSI samples was shown by absorption spectra at 77 K. The intensity in the whole spectrum of PSI-FCPI membranes was much higher than those of the other two complexes, while the spectral shape of PSI complexes was similar to that of cyanobacterial PSI core complexes. 77-K fluorescence spectra of the three PSI preparations exhibited different spectral shapes, especially peak positions and band widths. Based on these observations, we discuss the merits of three PSI preparations for evaluating excitation energy dynamics in diatom PSI-FCPI complexes.


Asunto(s)
Proteínas de Unión a Clorofila/metabolismo , Diatomeas/metabolismo , Transferencia de Energía , Complejo de Proteína del Fotosistema I/metabolismo , Pigmentos Biológicos/metabolismo , Xantófilas/metabolismo , Clorofila A/metabolismo , Fluorescencia , Electroforesis en Gel de Poliacrilamida Nativa
6.
Photosynth Res ; 141(3): 355-365, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30993504

RESUMEN

Controlling excitation energy flow is a fundamental ability of photosynthetic organisms to keep a better performance of photosynthesis. Among the organisms, diatoms have unique light-harvesting complexes, fucoxanthin chlorophyll (Chl) a/c-binding proteins. We have recently investigated light-adaptation mechanisms of a marine centric diatom, Chaetoceros gracilis, by spectroscopic techniques. However, it remains unclear how pennate diatoms regulate excitation energy under different growth light conditions. Here, we studied light-adaptation mechanisms in a marine pennate diatom Phaeodactylum tricornutum grown at 30 µmol photons m-2 s-1 and further incubated for 24 h either in the dark, or at 30 or 300 µmol photons m-2 s-1 light intensity, by time-resolved fluorescence (TRF) spectroscopy. The high-light incubated cells showed no detectable oxygen-evolving activity of photosystem II, indicating the occurrence of a severe photodamage. The photodamaged cells showed alterations of steady-state absorption and fluorescence spectra and TRF spectra compared with the dark and low-light adapted cells. In particular, excitation-energy quenching is significantly accelerated in the photodamaged cells as shown by mean lifetime analysis of the Chl fluorescence. These spectral changes by the high-light treatment may result from arrangements of pigment-protein complexes to maintain the photosynthetic performance under excess light illumination. These growth-light dependent spectral properties in P. tricornutum are largely different from those in C. gracilis, thus providing insights into the different light-adaptation mechanisms between the pennate and centric diatoms.


Asunto(s)
Diatomeas/fisiología , Diatomeas/efectos de la radiación , Luz , Clorofila/metabolismo , Oxígeno/metabolismo , Espectrometría de Fluorescencia , Factores de Tiempo
7.
Biochim Biophys Acta Bioenerg ; 1859(7): 524-530, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29660309

RESUMEN

Maintenance of energy balance under changeable light conditions is an essential function of photosynthetic organisms to achieve efficient photochemical reactions. Among the photosynthetic organisms, diatoms possess light-harvesting fucoxanthin chlorophyll (Chl) a/c-binding protein (FCP) as peripheral antennas. However, how diatoms regulate excitation-energy distribution between FCP and the two photosystem cores during light adaptation is poorly understood. In this study, we examined spectroscopic properties of a marine diatom Chaetoceros gracilis adapted in the dark and at photosynthetic photon flux density at 30 and 300 µmol photons m-2 s-1. Absorption spectra at 77 K showed significant changes in the Soret region, and 77-K steady-state fluorescence spectra showed significant differences in the spectral shape and relative fluorescence intensity originating from both PSII and PSI, among the cells grown under different light conditions. These results suggest alterations of pigment composition and their interactions under the different light conditions. These alterations affected the excitation-energy dynamics monitored by picosecond time-resolved fluorescence analyses at 77 K significantly. The contributions of Chls having lower energy levels than the reaction center Chls in the two photosystems to the energy dynamics were clearly identified in the three cells but with presumably different roles. These findings provide insights into the regulatory mechanism of excitation-energy balance in diatoms under various light conditions.


Asunto(s)
Clorofila/análisis , Diatomeas/metabolismo , Pigmentos Biológicos/análisis , Espectrometría de Fluorescencia/métodos , Clorofila A , Proteínas de Unión a Clorofila/análisis , Luz
8.
Regul Toxicol Pharmacol ; 94: 22-32, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29309809

RESUMEN

Acute inhalation studies are conducted in animals as part of chemical hazard identification and for classification and labelling. Current methods employ death as an endpoint (Organisation for Economic Co-operation and Development (OECD) test guideline (TG) 403 and TG436) while the recently approved fixed concentration procedure (FCP) (OECD TG433) uses fewer animals and replaces lethality as an endpoint with evident toxicity. Evident toxicity is the presence of clinical signs that predict that exposure to the next highest concentration will cause severe toxicity or death in most animals. Approval of TG433 was the result of an international initiative, led by the National Centre for the Replacement, Refinement & Reduction of Animals in Research (NC3Rs), which collected data from six laboratories on clinical signs recorded for inhalation studies on 172 substances. This paper summarises previously published data and describes the additional analyses of the dataset that were essential for approval of the TG.


Asunto(s)
Pruebas de Toxicidad Aguda/métodos , Administración por Inhalación , Alternativas al Uso de Animales/métodos , Animales , Femenino , Masculino
9.
Biochim Biophys Acta Bioenerg ; 1858(3): 218-230, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27989819

RESUMEN

When grown under intermittent light (IL), the pennate diatom Phaeodactylum tricornutum forms 'super' non-photochemical fluorescence quenching (NPQ) in response to excess light. The current model of diatom NPQ mechanism involves two quenching sites, one of which detaches from photosystem II reaction centres (RCIIs) and aggregates into oligomeric complexes. Here we addressed how antenna reorganisation controls NPQ kinetics in P. tricornutum cells grown under continuous light (CL) and IL. Overall, IL acclimation induced: (i) reorganisation of chloroplasts, containing greater pigment pools without a strongly enhanced operation of the xanthophyll cycle, and (ii) 'super NPQ' causing a remarkable reduction of the chlorophyll excited state lifetime at Fm'. Regardless of different levels of NPQ formed in both culture conditions, its dark recovery was rapid and similar fractions of their antenna uncoupled (~50%). Although antenna detachment relieved excitation pressure, it provided a minor protective contribution equivalent to NPQ~1, while the largest NPQ was 4.4±0.2 (CL) and 13±0.8 (IL). The PSII cross-section decrease took place only at relatively low NPQ values, beyond which the cross-section remained constant whilst NPQ continued to rise. This finding suggests that the energy trapping efficiency of diatom antenna quenchers cannot over-compete that of RCIIs, similarly to what has been observed on higher plants. We conclude that such 'economic photoprotection' operates to flexibly adjust the overall efficiency of diatom light harvesting.


Asunto(s)
Diatomeas/genética , Complejos de Proteína Captadores de Luz/genética , Complejo de Proteína del Fotosistema II/genética , Xantófilas/genética , Clorofila/análogos & derivados , Clorofila/genética , Clorofila/metabolismo , Clorofila A , Cloroplastos/genética , Cloroplastos/metabolismo , Diatomeas/crecimiento & desarrollo , Diatomeas/metabolismo , Fluorescencia , Cinética , Luz , Complejos de Proteína Captadores de Luz/química , Complejo de Proteína del Fotosistema II/metabolismo , Xantófilas/metabolismo
10.
Biochim Biophys Acta ; 1837(10): 1748-55, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24928296

RESUMEN

We report on energy transfer pathways in the main light-harvesting complex of photosynthetic relative of apicomplexan parasites, Chromera velia. This complex, denoted CLH, belongs to the family of FCP proteins and contains chlorophyll (Chl) a, violaxanthin, and the so far unidentified carbonyl carotenoid related to isofucoxanthin. The overall carotenoid-to-Chl-a energy transfer exhibits efficiency over 90% which is the largest among the FCP-like proteins studied so far. Three spectroscopically different isofucoxanthin-like molecules were identified in CLH, each having slightly different energy transfer efficiency that increases from isofucoxanthin-like molecules absorbing in the blue part of the spectrum to those absorbing in the reddest part of spectrum. Part of the energy transfer from carotenoids proceeds via the ultrafast S2 channel of both the violaxanthin and isofucoxanthin-like carotenoid, but major energy transfer pathway proceeds via the S1/ICT state of the isofucoxanthin-like carotenoid. Two S1/ICT-mediated channels characterized by time constants of ~0.5 and ~4ps were found. For the isofucoxanthin-like carotenoid excited at 480nm the slower channel dominates, while those excited at 540nm employs predominantly the fast 0.5ps channel. Comparing these data with the excited-state properties of the isofucoxanthin-like carotenoid in solution we conclude that, contrary to other members of the FCP family employing carbonyl carotenoids, CLH complex suppresses the charge transfer character of the S1/ICT state of the isofucoxanthin-like carotenoid to achieve the high carotenoid-to-Chl-a energy transfer efficiency.


Asunto(s)
Alveolados/metabolismo , Carotenoides/metabolismo , Clorofila/metabolismo , Transferencia de Energía , Complejos de Proteína Captadores de Luz/metabolismo , Clorofila A , Espectrometría de Fluorescencia
11.
Photosynth Res ; 126(2-3): 437-47, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26149177

RESUMEN

The major light-harvesting pigment protein complex (fucoxanthin-chlorophyll-binding protein complex; FCP) was purified from a marine centric diatom, Chaetoceros gracilis, by mild solubilization followed by sucrose density gradient centrifugation, and then characterized. The dynamic light scattering measurement showed unimodality, indicating that the complex was highly purified. The amount of chlorophyll a (Chl a) bound to the purified FCP accounted for more than 60 % of total cellular Chl a. The complex was composed of three abundant polypeptides, although there are nearly 30 FCP-related genes. The two major components were identified as Fcp3 (Lhcf3)- and Fcp4 (Lhcf4)-equivalent proteins based on their internal amino acid sequences and a two-dimensional isoelectric focusing electrophoresis analysis developed in this work. Compared with the thylakoids, the FCP complex showed higher contents of fucoxanthin and chlorophyll c but lower contents of the xanthophyll cycle pigments diadinoxanthin and diatoxanthin. Fluorescence excitation spectra analyses indicated that light harvesting, rather than photosystem protection, is the major function of the purified FCP complex, which is associated with more than 60 % of total cellular Chl a. These findings suggest that the huge amount of Chl bound to the FCP complex composed of Lhcf3, Lhcf4, and an unidentified minor protein has a light-harvesting function to allow efficient photosynthesis under the dim-light conditions in the ocean.


Asunto(s)
Diatomeas/metabolismo , Xantófilas/metabolismo , Proteínas Portadoras/metabolismo , Clorofila/metabolismo , Clorofila A , Diatomeas/efectos de la radiación , Luz , Complejos de Proteína Captadores de Luz/metabolismo , Complejo de Proteína del Fotosistema II/metabolismo , Espectrometría de Fluorescencia , Tilacoides/metabolismo
12.
Regul Toxicol Pharmacol ; 73(3): 770-9, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26505531

RESUMEN

Acute inhalation studies are conducted in animals as part of chemical hazard identification and characterisation, including for classification and labelling purposes. Current accepted methods use death as an endpoint (OECD TG403 and TG436), whereas the fixed concentration procedure (FCP) (draft OECD TG433) uses fewer animals and replaces lethality as an endpoint with 'evident toxicity.' Evident toxicity is defined as clear signs of toxicity that predict exposure to the next highest concentration will cause severe toxicity or death in most animals. A global initiative including 20 organisations, led by the National Centre for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs) has shared data on the clinical signs recorded during acute inhalation studies for 172 substances (primarily dusts or mists) with the aim of making evident toxicity more objective and transferable between laboratories. Pairs of studies (5 male or 5 female rats) with at least a two-fold change in concentration were analysed to determine if there are any signs at the lower dose that could have predicted severe toxicity or death at the higher concentration. The results show that signs such as body weight loss (>10% pre-dosing weight), irregular respiration, tremors and hypoactivity, seen at least once in at least one animal after the day of dosing are highly predictive (positive predictive value > 90%) of severe toxicity or death at the next highest concentration. The working group has used these data to propose changes to TG433 that incorporate a clear indication of the clinical signs that define evident toxicity.


Asunto(s)
Determinación de Punto Final/normas , Exposición por Inhalación/efectos adversos , Cooperación Internacional , Pruebas de Toxicidad Aguda/normas , Aerosoles , Animales , Conducta Animal/efectos de los fármacos , Consenso , Conducta Cooperativa , Relación Dosis-Respuesta a Droga , Femenino , Guías como Asunto , Humanos , Dosificación Letal Mediana , Masculino , Modelos Animales , Actividad Motora/efectos de los fármacos , Variaciones Dependientes del Observador , Polvos , Ratas , Reproducibilidad de los Resultados , Respiración/efectos de los fármacos , Factores de Tiempo , Pruebas de Toxicidad Aguda/métodos , Pérdida de Peso/efectos de los fármacos
13.
Biochim Biophys Acta ; 1827(10): 1226-34, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23856166

RESUMEN

Although the major light harvesting complexes of diatoms, called FCPs (fucoxanthin chlorophyll a/c binding proteins), are related to the cab proteins of higher plants, the structures of these light harvesting protein complexes are much less characterized. Here, a structural/functional model for the "core" of FCP, based on the sequence homology with LHCII, in which two fucoxanthins replace the central luteins and act as quenchers of the Chl a triplet states, is proposed. Combining the information obtained by time-resolved EPR spectroscopy on the triplet states populated under illumination, with quantum mechanical calculations, we discuss the chlorophyll triplet quenching in terms of the geometry of the chlorophyll-carotenoid pairs participating to the process. The results show that local structural rearrangements occur in FCP, with respect to LHCII, in the photoprotective site.


Asunto(s)
Proteínas de Unión a Clorofila/química , Clorofila/metabolismo , Diatomeas/metabolismo , Xantófilas/metabolismo , Clorofila A , Proteínas de Unión a Clorofila/metabolismo , Espectroscopía de Resonancia por Spin del Electrón , Transferencia de Energía , Luz
14.
Bioorg Med Chem Lett ; 24(24): 5606-5611, 2014 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-25466184

RESUMEN

Diverse functionalized representatives of (1-4)-S-thiodisaccharides, 6-9 were synthesized and assessed for cytotoxicity and apoptosis against human cancer cell lines (A549, LoVo, MCF-7 and HeLa). The FCP 6 was more active against MCF-7 cells (i.e., an estrogen-dependent breast cancer line), whereas other (1-4)-S-thiodisaccharides showed strongest activity against A549 cells (i.e., a lung adenocarcinoma line). We propose to use a concept of functional 'CARB-pharmacophores' when evaluating a potential for the compounds' general antineoplastic activity. Future studies will determine the reasons for cell-type specificity of these compounds. The thio-sugar motif appears to be a promising lead for future developments.


Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Tioazúcares/química , Tioazúcares/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cristalografía por Rayos X , Disacáridos/química , Células HeLa , Humanos , Concentración 50 Inhibidora , Células MCF-7 , Conformación Molecular
15.
Musculoskeletal Care ; 22(2): e1890, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38727724

RESUMEN

AIM: To develop a better understanding of the perceptions of first point of contact roles within primary care by pre-registration students of the Allied Health Professions (AHPs). BACKGROUND: General practice in the UK is under growing pressure from declining general practitioner (GP) numbers and increased service demand. The National Health Service (NHS) is attempting to mitigate this demand by making more effective use of its highly experienced workforce through the creation of first contact practitioners (FCPs). Working in primary care, FCPs are highly experienced AHPs with three or more years of relevant clinical experience. METHODS: An abductive qualitative research approach underpinned by a descriptive phenomenological methodology was adopted. Thematic analysis was used to analyse the focus group transcripts. FINDINGS: Twenty two final-year pre-registration AHP students participated in three focus groups. Two themes with sub-themes were identified: (1) Understanding of the role-pathway to the role; role clarity; and sources of knowledge. (2) Impact on service-positives and challenges. CONCLUSIONS: This study synthesised new findings from the previously unexplored FCP stakeholder of pre-registration AHP students. Participants generally understood the FCP's purpose of unburdening GPs and perceived the FCP model to contribute to the solution of rising clinical and financial pressures within the NHS, and primary care specifically. However, there was confusion regarding the scope of practice of an FCP. It is vital that the future workforce understand this role through effective education.


Asunto(s)
Grupos Focales , Atención Primaria de Salud , Humanos , Técnicos Medios en Salud/psicología , Técnicos Medios en Salud/educación , Masculino , Femenino , Actitud del Personal de Salud , Investigación Cualitativa , Rol Profesional , Reino Unido , Estudiantes del Área de la Salud/psicología
16.
Children (Basel) ; 11(1)2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38275442

RESUMEN

Early childhood intervention is crucial for the development of minors with disabilities or at risk. Family-centred planning (FCP), which involves families in care, stands out in this context. Despite its importance, little is known about professionals' experiences of its implementation. FCP aims to tailor services to the needs of the family and the child within the Spanish health system. This study highlights the importance of assessing professionals' perceptions of FCP. Professionals rooted in traditional approaches may resist change. To assess the implementation of FCPs, the study explores the perspectives of 25 healthcare professionals using qualitative methods to assess their experiences. The qualitative descriptive phenomenological design, following Giorgi's modified Husserlian approach, seeks to understand the essence of the phenomenon from the participants' perspective. Two main themes emerged: (1) a social and work organization that perpetuates rehabilitation or early stimulation practices and (2) a socio-family and work organization that promotes FCP adherence, along with subthemes and units of meaning. The evaluation reveals common challenges, such as the need for solid training and institutional support. Evaluating the experience of professionals is essential to overcome barriers and ensure the successful implementation of FCPs. Administrators have an important role to play in providing social, health, and educational alternatives.

17.
J Exp Bot ; 64(17): 5359-69, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24043854

RESUMEN

CLAVATA3 (CLV3)/ENDOSPERM SURROUNDING REGION (ESR)-related (CLE) proteins belong to a small peptide family conserved in plants. Recent studies in Arabidopsis and rice have revealed a key role for CLEs in mediating cell-cell communication and stem cell maintenance during plant development, but how CLE signalling controls root development in the rice remains largely unknown. Here it is shown that exogenous application of a synthetic dodeca-amino acid peptide corresponding to the CLE motif of the rice FON2-LIKE CLE PROTEIN2 (FCP2p) protein or overexpression of FCP2 terminates root apical meristem (RAM) activity and impairs late metaxylem formation. FCP2p treatment suppresses the expression of the rice QUIESCENT-CENTER-SPECIFIC HOMEOBOX (QHB) gene, a putative orthologue of Arabidopsis WUSCHEL (WUS)-RELATED HOMEOBOX 5 (WOX5) gene, in both quiescent centre and late metaxylem cells; whereas inducible overexpression of QHB reduces the sensitivity of rice to FCP2p treatment. These results together suggest that in rice RAM maintenance and late metaxylem development are probably controlled by the mutual regulation between FCP2 and QHB. Moreover, a cross-species peptide treatment experiment in Arabidopsis implies that FCP2 has both evolutionarily conserved and species-specific roles in root development.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Oryza/fisiología , Péptidos/farmacología , Transducción de Señal , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Arabidopsis/citología , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Arabidopsis/fisiología , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Comunicación Celular , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Meristema/citología , Meristema/genética , Meristema/crecimiento & desarrollo , Meristema/fisiología , Oryza/citología , Oryza/efectos de los fármacos , Oryza/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raíces de Plantas/citología , Raíces de Plantas/genética , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/fisiología , Haz Vascular de Plantas/citología , Haz Vascular de Plantas/genética , Haz Vascular de Plantas/crecimiento & desarrollo , Haz Vascular de Plantas/fisiología , Plantas Modificadas Genéticamente , Especificidad de la Especie , Xilema/citología , Xilema/genética , Xilema/crecimiento & desarrollo , Xilema/fisiología
18.
Physiotherapy ; 121: 58-68, 2023 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-37852150

RESUMEN

BACKGROUND: Patients at risk of preventable sickness absence frequently attend at primary care. First contact physiotherapists (FCP) may provide an optimal way of reducing this risk; however, there is significant variability in clinical practice, limited research directing best practice and this work and health role is traditionally seen as outside of the 'therapeutic relationship'. If FCP's training and development in this area is considered, FCP's will be able to effectively conduct fitness for work and sickness absence certification within UK primary care settings. AIMS: This study aimed to reach expert consensus for work-related competencies for FCP practice for patients at risk of preventable sickness absence. METHODS: A modified Delphi technique involved a UK-wide FCP expert panel completing three rounds of an online questionnaire. The initial 30-competency questionnaire, based on two separate Nominal Group Techniques in a FCP and Association of Chartered Physiotherapists in Occupational Health and Ergonomics (ACPOHE) physiotherapist cohort and Health Education England's published Roadmap to Practice, covered occupational health specific items (knowledge and skills) related to the topic. Consensus threshold was set a priori at 70% level of group agreement. Items not reaching consensus were modified and new items added based on themes from qualitative data from the open-ended free text questions present in each section. Items that reached values greater than or equal to 70% of agreement among experts were considered definitive for the competency items. Items between 51% and 69% of agreement were included for the next round and those items with less than or equal to 50% of agreement were considered unnecessary and were excluded. In the third round, the occupational health (OH) specific contents for primary care were classified according to the degree of consensus as follows: strong (≥70% of agreement), moderate (51-69% of agreement) and weak (50% of agreement) based on the maximum consensus reached. RESULTS: Of the 30 initial competencies, 20 (67%) reached a strong degree of consensus and 2 (7%) reached a moderate degree of consensus and 8 (27%) competencies were not recommended (≤50% of agreement). 20 OH specific competencies reached a priori consensus level of agreement to provide the final group list. CONCLUSIONS: This paper provides an empirically derived list of OH competencies for FCP education in primary care 'first point of care' physiotherapy with a high level of expert agreement and high retention rate between rounds. CONTRIBUTION OF THE PAPER.

19.
Exp Ther Med ; 25(4): 185, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37021066

RESUMEN

The majority of colorectal polyps in adults are adenomatous polyps, while hamartoma polyps are rare. Juvenile polyps are the most common type of polyp in children; however, they are rare in adults. Fecal calprotectin (FCP) is commonly elevated in inflammatory bowel disease and is rarely studied in juvenile rectal polyps. Reports of elevated FCP in solitary juvenile rectal polyps of adults are rare. A 57-year-old female was admitted to The Affiliated Hospital of Qingdao University (Qingdao, China) for treatment due to intermittent stool with mucus and blood. Colonoscopy revealed a solitary polyp in the rectum with a diameter of ~2.0 cm, a short and wide subpedicle, with congested and swollen mucosa on the surface and chicken skin-like changes in the surrounding mucosa. The patient had no family history of colorectal polyps or cancer. Endoscopic submucosal dissection was used to remove the polyp. Histopathological examination indicated that the polyp was a juvenile polyp and no signs of malignancy were found. The present case report describes details on this case of an adult patient with a solitary juvenile rectal polyp with chicken skin-like changes in the surrounding mucosa and high FCP.

20.
Compr Psychoneuroendocrinol ; 10: 100128, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35755206

RESUMEN

Background: Neurocognitive impairment is common in people with Sickle Cell Disease (SCD) and evidence is accumulating that sleep disturbances play a role. The interaction between cortisol and sleep in the general population is associated with cognition as well as general wellbeing but there are few data in SCD. We aimed to understand the relationship between cortisol and sleep in individuals with SCD and explored associations with cognition. Methods: Forty-five participants of black heritage (SCD: N = 27, 9-29 years, 16 females; Controls: N = 18, 11-25 years, 13 females) were recruited from the community between 2018 - 2020. Participants completed standardized questionnaires about their sleep behaviour and wore actigraphy MotionWatch8 for 7 nights to assess nocturnal sleep patterns. Salivary cortisol samples were taken on wakening and 3 times after 14:00. Cognition was assessed using the Wechsler Intelligence Scales for children and adults. Results: People with SCD took longer to fall asleep and experienced greater wake bouts, mobile minutes and fragmented sleep compared to controls. Although non-significant, people with SCD experienced lower morning cortisol, with a flattened diurnal cortisol ratio compared to controls. Interestingly, SCD participants, but not controls, with low diurnal variation scored lowest on processing speed (PSI) and perceptual reasoning index (PRI). A moderator analysis revealed that the effect of morning cortisol and diurnal cortisol ratio on PRI by group health (i.e., SCD and healthy controls) depended on sleep quality. Discussion: Sleep and cortisol may play a crucial role in the expression of cognitive difficulties seen in SCD. This should be considered for the development of interventions to optimise cognitive functioning and sleep. This, in turn, could positively impact on secretion of cortisol and general health in SCD.

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