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1.
Int J Mol Sci ; 24(6)2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36982678

RESUMO

Bisphenol A (BPA) promotes colon cancer by altering the physiological functions of hormones. Quercetin (Q) can regulate signaling pathways through hormone receptors, inhibiting cancer cells. The antiproliferative effects of Q and its fermented extract (FEQ, obtained by Q gastrointestinal digestion and in vitro colonic fermentation) were analyzed in HT-29 cells exposed to BPA. Polyphenols were quantified in FEQ by HPLC and their antioxidant capacity by DPPH and ORAC. Q and 3,4-dihydroxyphenylacetic acid (DOPAC) were quantified in FEQ. Q and FEQ exhibited antioxidant capacity. Cell viability with Q+BPA and FEQ+BPA was 60% and 50%, respectively; less than 20% of dead cells were associated with the necrosis process (LDH). Treatments with Q and Q+BPA induced cell cycle arrest in the G0/G1 phase, and FEQ and FEQ+BPA in the S phase. Compared with other treatments, Q positively modulated ESR2 and GPR30 genes. Using a gene microarray of the p53 pathway, Q, Q+BPA, FEQ and FEQ+BPA positively modulated genes involved in apoptosis and cell cycle arrest; bisphenol inhibited the expression of pro-apoptotic and cell cycle repressor genes. In silico analyses demonstrated the binding affinity of Q > BPA > DOPAC molecules for ERα and ERß. Further studies are needed to understand the role of disruptors in colon cancer.


Assuntos
Neoplasias do Colo , Quercetina , Humanos , Quercetina/farmacologia , Proliferação de Células , Antioxidantes/farmacologia , Células HT29 , Ácido 3,4-Di-Hidroxifenilacético/farmacologia , Neoplasias do Colo/tratamento farmacológico , Compostos Benzidrílicos/farmacologia
2.
Molecules ; 27(19)2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36235125

RESUMO

The estrogenic receptor beta (ERß) protects against carcinogenesis by stimulating apoptosis. Bisphenol A (BPA) is related to promoting cancer, and naringenin has chemoprotective activities both can bind to ERß. Naringenin in the colon is metabolized by the microbiota. Cancer involves genetic and epigenetic mechanisms, including miRNAs. The objective of the present study was to evaluate the co-exposure effect of colonic in vitro fermented extract of naringenin (FEN) and BPA, to elucidate molecular effects in HT-29 colon cancer cell line. For this, we quantified genes related to the p53 signaling pathway as well as ERß, miR-200c, and miR-141. As an important result, naringenin (IC50 250 µM) and FEN (IC50 37%) promoted intrinsic pathways of apoptosis through phosphatase and tensin homolog (PTEN) (+2.70, +1.72-fold, respectively) and CASP9 (+3.99, +2.03-fold, respectively) expression. BPA decreased the expression of PTEN (-3.46-fold) gene regulated by miR-200. We suggest that once co-exposed, cells undergo a greater stress forcing them to mediate other extrinsic apoptosis mechanisms associated with death domain FASL. In turn, these findings are related to the increase of ERß (5.3-fold with naringenin and 13.67-fold with FEN) gene expression, important in the inhibition of carcinogenic development.


Assuntos
Neoplasias do Colo , MicroRNAs , Compostos Benzidrílicos , Proliferação de Células , Neoplasias do Colo/genética , Receptor beta de Estrogênio/genética , Receptor beta de Estrogênio/metabolismo , Fermentação , Flavanonas , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Fenóis , Transdução de Sinais , Tensinas/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
3.
Rev Esp Enferm Dig ; 114(8): 448-454, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34470450

RESUMO

BACKGROUND: the impact of the COVID-19 outbreak and lockdown on liver transplant (LT) patients remains unknown. The aim of this cross-sectional study was to assess the consequences of the COVID-19 pandemic on the physical and mental health of LT patients during the lockdown period. METHODS: a web-based questionnaire was emailed to 238 LT patients undergoing regular follow-up at our unit between August and October 2020. This pseudonymized survey explored demographic and lifestyle variables (i.e., eating and physical habits), disruptions in routine medical care, different dimensions of mental health, COVID-19-related mood and coping (worries/anxiety, depression, insomnia, fear of COVID, resilience, etc.) and health perception using different validated instruments. RESULTS: altogether, 48.7 % (116 of 238) LT recipients accepted to participate in the study, 104 of whom gave their consent to publish the data. The median age was 63 years. Up to 39.4 % presented worrying scores indicating moderate/severe generalized anxiety disorder (GAD), whereas 25.5 % exhibited moderate/severe insomnia and only 10.5 % moderate/severe depression. Forty patients (38.5 %) gained weight, 24 % experienced a worsening in their eating habits and 63.4 % referred to practicing less or much less exercise during the lockdown. Only 25 % perceived a worsening in the control of their chronic comorbidities. Missed medical appointments (0.9 %) or poor adherence to therapy (1.9 %) were exceptional. CONCLUSIONS: COVID-19 lockdown has negatively impacted the mental and physical health of LT patients. Long-term consequences remain unclear.


Assuntos
COVID-19 , Transplante de Fígado , Distúrbios do Início e da Manutenção do Sono , Ansiedade/epidemiologia , Ansiedade/psicologia , Controle de Doenças Transmissíveis , Estudos Transversais , Humanos , Pessoa de Meia-Idade , Pandemias , SARS-CoV-2 , Distúrbios do Início e da Manutenção do Sono/epidemiologia
4.
Int J Mol Sci ; 19(11)2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30445779

RESUMO

Self-incompatibility (SI) is one of the most efficient mechanisms to promote out-crossing in plants. However, SI could be a problem for fruit production. An example is apricot (Prunus armeniaca), in which, as in other species of the Rosaceae, SI is determined by an S-RNase-based-Gametophytic Self-Incompatibility (GSI) system. Incompatibility relationships between cultivars can be established by an S-allele genotyping PCR strategy. Until recently, most of the traditional European apricot cultivars were self-compatible but several breeding programs have introduced an increasing number of new cultivars whose pollination requirements are unknown. To fill this gap, we have identified the S-allele of 44 apricot genotypes, of which 43 are reported here for the first time. The identification of Sc in 15 genotypes suggests that those cultivars are self-compatible. In five genotypes, self-(in)compatibility was established by the observation of pollen tube growth in self-pollinated flowers, since PCR analysis could not allowed distinguishing between the Sc and S8 alleles. Self-incompatible genotypes were assigned to their corresponding self-incompatibility groups. The knowledge of incompatibility relationships between apricot cultivars can be a highly valuable tool for the development of future breeding programs by selecting the appropriate parents and for efficient orchard design by planting self-compatible and inter-compatible cultivars.


Assuntos
Alelos , Reação em Cadeia da Polimerase/métodos , Prunus armeniaca/genética , Ribonucleases/genética , Autoincompatibilidade em Angiospermas/genética , Análise de Sequência de DNA , Genótipo , Íntrons/genética , Tubo Polínico/crescimento & desenvolvimento , Polinização , Ribonucleases/metabolismo
5.
Aging Ment Health ; 21(4): 362-368, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-26460518

RESUMO

BACKGROUND: Several studies have shown that anxiety is associated with a better memory of negative events. However, this anxiety-related memory bias has not been studied in the elderly, in which there is a preferential processing of positive information. OBJECTIVES: To study the effect of anxiety in a recognition task and an autobiographical memory task in 102 older adults with high and low levels of trait anxiety. METHOD: Negative, positive and neutral pictures were used in the recognition task. In the autobiographical memory task, memories of the participants' lives were recorded, how they felt when thinking about them, and the personal relevance of these memories. RESULTS: In the recognition task, no anxiety-related bias was found toward negative information. Individuals with high trait anxiety were found to remember less positive pictures than those with low trait anxiety. In the autobiographical memory task, both groups remembered negative and positive events equally. However, people with high trait anxiety remembered life experiences with more negative emotions, especially when remembering negative events. Individuals with low trait anxiety tended to feel more positive emotions when remembering their life experiences and most of these referred to feeling positive emotions when remembering negative events. CONCLUSIONS: Older adults with anxiety tend to recognize less positive information and to present more negative emotions when remembering life events; while individuals without anxiety have a more positive experience of negative memories.


Assuntos
Envelhecimento/fisiologia , Ansiedade/fisiopatologia , Emoções/fisiologia , Avaliação Geriátrica/métodos , Memória/fisiologia , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/psicologia , Ansiedade/psicologia , Feminino , Avaliação Geriátrica/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Reconhecimento Psicológico/fisiologia , Análise e Desempenho de Tarefas
6.
Ann Vasc Surg ; 35: 204.e1-4, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27236094

RESUMO

Despite a high incidence of Staphylococcus aureus bacteremia in hemodialysis patients, bacterial invasion with aortic wall infection resulting in a pseudoaneurysm rarely occurs. This report describes a case of mycotic pseudoaneurysm of the abdominal aorta that grew rapidly and ruptured into the distal vena cava causing persistent bacteremia in a patient undergoing hemodialysis complicated with oxacillin-resistant S. aureus bacteremia.


Assuntos
Falso Aneurisma/microbiologia , Aneurisma Infectado/microbiologia , Antibacterianos/uso terapêutico , Aneurisma da Aorta Abdominal/microbiologia , Ruptura Aórtica/microbiologia , Bacteriemia/microbiologia , Resistência a Medicamentos , Falência Renal Crônica/terapia , Oxacilina/uso terapêutico , Diálise Renal/efeitos adversos , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Falso Aneurisma/diagnóstico por imagem , Falso Aneurisma/cirurgia , Aneurisma Infectado/diagnóstico por imagem , Aneurisma Infectado/cirurgia , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/cirurgia , Ruptura Aórtica/diagnóstico por imagem , Ruptura Aórtica/cirurgia , Aortografia/métodos , Bacteriemia/diagnóstico , Angiografia por Tomografia Computadorizada , Humanos , Falência Renal Crônica/diagnóstico , Masculino , Pessoa de Meia-Idade , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/patogenicidade , Resultado do Tratamento
7.
Compr Psychiatry ; 55(1): 199-205, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23993221

RESUMO

OBJECTIVE: To assess the emotion recognition in familiar and unknown faces in a sample of schizophrenic patients and healthy controls. METHODS: Face emotion recognition of 18 outpatients diagnosed with schizophrenia (DSM-IVTR) and 18 healthy volunteers was assessed with two Emotion Recognition Tasks using familiar faces and unknown faces. Each subject was accompanied by 4 familiar people (parents, siblings or friends), which were photographed by expressing the 6 Ekman's basic emotions. Face emotion recognition in familiar faces was assessed with this ad hoc instrument. In each case, the patient scored (from 1 to 10) the subjective familiarity and affective valence corresponding to each person. RESULTS: Patients with schizophrenia not only showed a deficit in the recognition of emotions on unknown faces (p=.01), but they also showed an even more pronounced deficit on familiar faces (p=.001). Controls had a similar success rate in the unknown faces task (mean: 18 +/- 2.2) and the familiar face task (mean: 17.4 +/- 3). However, patients had a significantly lower score in the familiar faces task (mean: 13.2 +/- 3.8) than in the unknown faces task (mean: 16 +/- 2.4; p<.05). In both tests, the highest number of errors was with emotions of anger and fear. Subjectively, the patient group showed a lower level of familiarity and emotional valence to their respective relatives (p<.01). CONCLUSIONS: The sense of familiarity may be a factor involved in the face emotion recognition and it may be disturbed in schizophrenia.


Assuntos
Emoções , Expressão Facial , Reconhecimento Psicológico , Psicologia do Esquizofrênico , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
8.
Biosci Rep ; 43(8)2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37417269

RESUMO

Lipid transporters play a crucial role in supporting essential cellular processes such as organelle assembly, vesicular trafficking, and lipid homeostasis by driving lipid transport across membranes. Cryo-electron microscopy has recently resolved the structures of several ATP-dependent lipid transporters, but functional characterization remains a major challenge. Although studies of detergent-purified proteins have advanced our understanding of these transporters, in vitro evidence for lipid transport is still limited to a few ATP-dependent lipid transporters. Reconstitution into model membranes, such as liposomes, is a suitable approach to study lipid transporters in vitro and to investigate their key molecular features. In this review, we discuss the current approaches for reconstituting ATP-driven lipid transporters into large liposomes and common techniques used to study lipid transport in proteoliposomes. We also highlight the existing knowledge on the regulatory mechanisms that modulate the activity of lipid transporters, and finally, we address the limitations of the current approaches and future perspectives in this field.


Assuntos
Transportadores de Cassetes de Ligação de ATP , Lipossomos , Lipossomos/química , Transportadores de Cassetes de Ligação de ATP/metabolismo , Microscopia Crioeletrônica , Proteínas de Membrana Transportadoras , Trifosfato de Adenosina/metabolismo
9.
Plants (Basel) ; 12(17)2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37687272

RESUMO

Apricot has undergone an important cultivar renewal during the last years in response to productive and commercial changes in the crop. The impact of the sharka disease (plum pox virus) prompted the release of cultivars resistant/tolerant to this virus, leading to a major cultivar renewal worldwide. This has caused high variability in chilling requirements on new releases that remain unknown in many cases. In many apricot-growing areas, the lack of winter chilling is becoming a limiting factor in recent years. To deal with this situation, growers must choose cultivars well adapted to their areas. However, the information available on the agroclimatic requirements of the cultivars is very limited. To fill this gap, in this work, we have characterized the chilling requirements of 13 new apricot cultivars from Europe (France, Greece and Spain) and North America (USA) in two experimental collections in Aragón (Spain). We established the chilling period using male meiosis as a biomarker for endodormancy release over two years. Chilling requirements ranged from 51.9 Chill Portions (CP) to 70.9 CP. Knowing the chilling requirements of cultivars will help growers to select suitable cultivars adapted to the chill availability of their region.

10.
Bio Protoc ; 13(13): e4771, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37456343

RESUMO

Eukaryotic cells use a series of membrane transporters to control the movement of lipids across their plasma membrane. Several tools and techniques have been developed to analyze the activity of these transporters in the plasma membrane of mammalian cells. Among them, assays based on fluorescence microscopy in combination with fluorescent lipid probes are particularly suitable, allowing visualization of lipid internalization in living cells. Here, we provide a step-by-step protocol for mammalian cell culture, lipid probe preparation, cell labeling, and confocal imaging to monitor lipid internalization by lipid flippases at the plasma membrane based on lipid probes carrying a fluorophore at a short-chain fatty acid. The protocol allows studying a wide range of mammalian cell lines, to test the impact of gene knockouts on lipid internalization at the plasma membrane and changes in lipid uptake during cell differentiation. Key features Visualization and quantification of lipid internalization by lipid flippases at the plasma membrane based on confocal microscopy. Assay is performed on living adherent mammalian cells in culture. The protocol can be easily modified to a wide variety of mammalian cell lines.

11.
Protein Sci ; 33(3): e4855, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38063271

RESUMO

P4-ATPases in complex with Cdc50 subunits are lipid flippases that couple ATP hydrolysis with lipid transport to the cytoplasmic leaflet of membranes to create lipid asymmetry. Such vectorial transport has been shown to contribute to vesicle formation in the late secretory pathway. Some flippases are regulated by autoinhibitory regions that can be destabilized by protein kinase-mediated phosphorylation and possibly by binding of cytosolic proteins. In addition, the binding of lipids to flippases may also induce conformational changes required for the activity of these transporters. Here, we address the role of phosphatidylinositol-4-phosphate (PI4P) and the terminal autoinhibitory tails on the lipid flipping activity of the yeast lipid flippase Drs2-Cdc50. By functionally reconstituting the full-length and truncated forms of Drs2 in a 1:1 complex with the Cdc50 subunit, we provide compelling evidence that lipid flippase activity is exclusively detected for the truncated Drs2 variant and is dependent on the presence of the phosphoinositide PI4P. These findings highlight the critical role of phosphoinositides as lipid co-factors in the regulation of lipid transport by the Drs2-Cdc50 flippase.

12.
Polymers (Basel) ; 15(7)2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37050374

RESUMO

This paper presents the results obtained from the chemical activation of bacterial nanocellulose (BCN) using fique juice as a culture medium. BNC activation (BNCA) was carried out with H3PO4 and KOH at activation temperatures between 500 °C to 800 °C. The materials obtained were characterized morphologically, physicochemically, superficially, and electrochemically, using scanning electron microscopy, X-ray photoelectron spectroscopy (XPS), the physisorption of gases N2 and CO2 at 77 K and 273 K, respectively, cyclic voltammetry, chronopotentiometry, and electrochemical impedance spectroscopy (EIS). The samples activated with H3PO4 presented specific surface areas (SBET) around 780 m2 g-1, while those activated with KOH values presented specific surface areas between 680 and 893 m2 g-1. The XPS analysis showed that the PXPS percentage on the surface after H3PO4 activation was 11 wt%. The energy storage capacitance values ranged between 97.5 F g-1 and 220 F g-1 by EIS in 1 M H2SO4. The samples with the best electrochemical performance were activated with KOH at 700 °C and 800 °C, mainly due to the high SBET available and the accessibility of the microporosity. The capacitance of BNCAs was mainly improved by electrostatic effects due to the SBET rather than that of pseudocapacitive ones due to the presence of phosphorus heteroatoms.

13.
Pharmaceutics ; 15(6)2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37376109

RESUMO

Methotrexate (MTX) is a commonly used drug for the treatment of rheumatoid arthritis (RA), but its effectiveness can vary greatly among patients. Pharmacogenetics, the study of how genetic variations can affect drug response, has the potential to improve the personalized treatment of RA by identifying genetic markers that can predict a patient's response to MTX. However, the field of MTX pharmacogenetics is still in its early stages and there is a lack of consistency among studies. This study aimed to identify genetic markers associated with MTX efficacy and toxicity in a large sample of RA patients, and to investigate the role of clinical covariates and sex-specific effects. Our results have identified an association of ITPA rs1127354 and ABCB1 rs1045642 with response to MTX, polymorphisms of FPGS rs1544105, GGH rs1800909, and MTHFR genes with disease remission, GGH rs1800909 and MTHFR rs1801131 polymorphisms with all adverse events, and ADA rs244076 and MTHFR rs1801131 and rs1801133, However, clinical covariates were more important factors to consider when building predictive models. These findings highlight the potential of pharmacogenetics to improve personalized treatment of RA, but also emphasize the need for further research to fully understand the complex mechanisms involved.

14.
Plants (Basel) ; 11(15)2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35956497

RESUMO

In recent years, an important renewal of apricot cultivars is taking place worldwide, with the introduction of many new releases. Self-incompatible genotypes tolerant to the sharka disease caused by the plum pox virus (PPV), which can severely reduce fruit production and quality, are being used as parents in most breeding programs. As a result, the self-incompatibility trait present in most of those accessions can be transmitted to the offspring, leading to the release of new self-incompatible cultivars. This situation can considerably affect apricot management, since pollination requirements were traditionally not considered in this crop and information is lacking for many cultivars. Thus, the objective of this work was to determine the pollination requirements of a group of new apricot cultivars by molecular identification of the S-alleles through PCR amplification of RNase and SFB regions with different primer combinations. The S-genotype of 66 apricot cultivars is reported, 41 for the first time. Forty-nine cultivars were considered self-compatible and 12 self-incompatible, which were allocated in their corresponding incompatibility groups. Additionally, the available information was reviewed and added to the new results obtained, resulting in a compilation of the pollination requirements of 235 apricot cultivars. This information will allow an efficient selection of parents in apricot breeding programs, the proper design of new orchards, and the identification and solution of production problems associated with a lack of fruit set in established orchards. The diversity at the S-locus observed in the cultivars developed in breeding programs indicates a possible genetic bottleneck due to the use of a reduced number of parents.

15.
Bio Protoc ; 12(4): e4330, 2022 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-35340299

RESUMO

All eukaryotic cells are equipped with transmembrane lipid transporters, which are key players in membrane lipid asymmetry, vesicular trafficking, and membrane fusion. The link between mutations in these transporters and disease in humans highlights their essential role in cell homeostasis. Yet, many key features of their activities, their substrate specificity, and their regulation remain to be elucidated. Here, we describe an optimized quantitative flow cytometry-based lipid uptake assay utilizing nitrobenzoxadiazolyl (NBD) fluorescent lipids to study lipid internalization in mammalian cell lines, which allows characterizing lipid transporter activities at the plasma membrane. This approach allows for a rapid analysis of large cell populations, thereby greatly reducing sampling variability. The protocol can be applied to study a wide range of mammalian cell lines, to test the impact of gene knockouts on lipid internalization at the plasma membrane, and to uncover the dynamics of lipid transport at the plasma membrane. Graphic abstract: Internalization of NBD-labeled lipids from the plasma membrane of CHO-K1 cells.

16.
Front Plant Sci ; 13: 842333, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35463418

RESUMO

Dormancy is an adaptive strategy in plants to survive under unfavorable climatic conditions during winter. In temperate regions, most fruit trees need exposure to a certain period of low temperatures to overcome endodormancy. After endodormancy release, exposure to warm temperatures is needed to flower (ecodormancy). Chilling and heat requirements are genetically determined and, therefore, are specific for each species and cultivar. The lack of sufficient winter chilling can cause failures in flowering and fruiting, thereby compromising yield. Thus, the knowledge of the chilling and heat requirements is essential to optimize cultivar selection for different edaphoclimatic conditions. However, the lack of phenological or biological markers linked to the dormant and forcing periods makes it difficult to establish the end of endodormancy. This has led to indirect estimates that are usually not valid in different agroclimatic conditions. The increasing number of milder winters caused by climatic change and the continuous release of new cultivars emphasize the necessity of a proper biological marker linked to the endo- to ecodormancy transition for an accurate estimation of the agroclimatic requirements (AR) of each cultivar. In this work, male meiosis is evaluated as a biomarker to determine endodormancy release and to estimate both chilling and heat requirements in apricot. For this purpose, pollen development was characterized histochemically in 20 cultivars over 8 years, and the developmental stages were related to dormancy. Results were compared to three approaches that indirectly estimate the breaking of dormancy: an experimental methodology by evaluating bud growth in shoots collected periodically throughout the winter months and transferred to forcing chambers over 3 years, and two statistical approaches that relate seasonal temperatures and blooming dates in a series of 11-20 years by correlation and partial least square regression. The results disclose that male meiosis is a possible biomarker to determine the end of endodormancy and estimate AR in apricot.

17.
Elife ; 112022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35416773

RESUMO

P4-ATPases flip lipids from the exoplasmic to the cytosolic leaflet, thus maintaining lipid asymmetry in eukaryotic cell membranes. Mutations in several human P4-ATPase genes are associated with severe diseases, for example in ATP8B1 causing progressive familial intrahepatic cholestasis, a rare inherited disorder progressing toward liver failure. ATP8B1 forms a binary complex with CDC50A and displays a broad specificity to glycerophospholipids, but regulatory mechanisms are unknown. Here, we report functional studies and the cryo-EM structure of the human lipid flippase ATP8B1-CDC50A at 3.1 Å resolution. We find that ATP8B1 is autoinhibited by its N- and C-terminal tails, which form extensive interactions with the catalytic sites and flexible domain interfaces. Consistently, ATP hydrolysis is unleashed by truncation of the C-terminus, but also requires phosphoinositides, most markedly phosphatidylinositol-3,4,5-phosphate (PI(3,4,5)P3), and removal of both N- and C-termini results in full activation. Restored inhibition of ATP8B1 truncation constructs with a synthetic peptide mimicking the C-terminal segment further suggests molecular communication between N- and C-termini in the autoinhibition and demonstrates that the regulatory mechanism can be interfered with by exogenous compounds. A recurring (G/A)(Y/F)AFS motif of the C-terminal segment suggests that this mechanism is employed widely across P4-ATPase lipid flippases in plasma membrane and endomembranes.


Assuntos
Adenosina Trifosfatases , Colestase Intra-Hepática , Fosfatidilinositóis , Adenosina Trifosfatases/metabolismo , Membrana Celular/metabolismo , Colestase Intra-Hepática/genética , Colestase Intra-Hepática/metabolismo , Humanos , Mutação , Fosfatidilinositóis/metabolismo , Proteínas de Transferência de Fosfolipídeos/metabolismo
18.
Tree Physiol ; 41(4): 619-630, 2021 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-32453409

RESUMO

Male meiosis in temperate fruit trees occurs in the anthers once a year, synchronized with the seasons. The alternation of dormant and growth cycles determines the optimum moment for the male gametophyte formation, a process sensitive to both cold and warm temperatures. This ensures pollen viability and subsequent reproduction success that guarantee fruit production. In this work, we explore how male meiosis is framed by seasonality in sweet cherry. For this purpose, the dormant phases, male meiosis and blooming dates were established in four cultivars with different flowering dates and chilling requirements over 7 years. The chilling and heat requirements for each cultivar were empirically estimated, and chilling and heat temperatures were quantified according to the Dynamic and Growing Degree Hours (GDH) models, respectively. Endodormancy was overcome approximately a fortnight earlier during the colder winters than during the milder winters. Against our initial hypothesis, these differences were not clearly reflected in the time of male meiosis. The period between chilling fulfillment and meiosis lasted several weeks, during which a high amount of GDH accumulated. Results showed that male meiosis is conditioned by endodormancy but especially by warm temperatures, during the forcing period. This differs from what has been described in other related species and creates a framework for further studies to understand the strategies of synchronizing dormancy with seasons.


Assuntos
Prunus avium , Flores , Meiose , Estações do Ano , Temperatura
19.
Rev Esp Geriatr Gerontol ; 45(6): 339-42, 2010.
Artigo em Espanhol | MEDLINE | ID: mdl-21071111

RESUMO

INTRODUCTION: The main goal of the current research was to study the relationship between holding negative aging stereotypes and cognitive performance in a cognitive stimulation program in an older adult group (n=55) with Mild Cognitive Impairment. MATERIAL AND METHODS: Performance and stereotypes were contrasted before and after the cognitive stimulation program. RESULTS: Firstly, results showed a significant improvement in associative learning and verbal recall, as well as significant stereotypes score reduction after treatment. Secondly, those who improved their associative learning performance had a higher stereotypes score before the program. Even though, this group also reduced their stereotype score. CONCLUSIONS: These findings show that people who improve their cognitive performance also reduce their stereotypes score. This relationship is very novel, because although the correlation between absence of stereotype and better cognitive performance has been found in the literature, a positive correlation between stereotype change and cognitive performance after a psychological treatment has not been observed before.


Assuntos
Terapia Cognitivo-Comportamental , Estereotipagem , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
20.
J Vis Exp ; (160)2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32628154

RESUMO

Self-incompatibility in Rosaceae is determined by a Gametophytic Self-Incompatibility System (GSI) that is mainly controlled by the multiallelic locus S. In apricot, the determination of self- and inter-(in)compatibility relationships is increasingly important, since the release of an important number of new cultivars has resulted in the increase of cultivars with unknown pollination requirements. Here, we describe a methodology that combines the determination of self-(in)compatibility by hand-pollinations and microscopy with the identification of the S-genotype by PCR analysis. For self-(in)compatibility determination, flowers at balloon stage from each cultivar were collected in the field, hand-pollinated in the laboratory, fixed, and stained with aniline blue for the observation of pollen tube behavior under the fluorescence microscopy. For the establishment of incompatibility relationships between cultivars, DNA from each cultivar was extracted from young leaves and S-alleles were identified by PCR. This approach allows establishing incompatibility groups and elucidate incompatibility relationships between cultivars, which provides a valuable information to choose suitable pollinizers in the design of new orchards and to select appropriate parents in breeding programs.


Assuntos
Polinização , Prunus armeniaca/fisiologia , DNA de Plantas/análise , Flores/fisiologia , Genótipo , Microscopia de Fluorescência , Folhas de Planta/genética , Pólen/fisiologia , Reação em Cadeia da Polimerase , Prunus armeniaca/genética
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