Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 26
Filtrar
1.
Cell ; 171(5): 1224-1224.e1, 2017 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-29149609

RESUMO

The endoplasmic reticulum (ER) consists of the nuclear envelope and a reticulated interconnected network of tubules and sheets. ER sheets are studded with ribosomes and provide the entryway for proteins into the secretory pathway. ER tubules move dynamically on microtubules and form membrane contact sites with other organelles, where membranes are tethered, but not fused. This Snapshot reviews key biological processes that take place at ER contact sites with the Golgi, endosomes, and mitochondria.


Assuntos
Retículo Endoplasmático/fisiologia , Animais , Transporte Biológico , Cálcio/metabolismo , Humanos , Metabolismo dos Lipídeos , Proteínas/metabolismo
2.
EMBO J ; 41(8): e108587, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35023587

RESUMO

The apoptotic executioner protein BAX and the dynamin-like protein DRP1 co-localize at mitochondria during apoptosis to mediate mitochondrial permeabilization and fragmentation. However, the molecular basis and functional consequences of this interplay remain unknown. Here, we show that BAX and DRP1 physically interact, and that this interaction is enhanced during apoptosis. Complex formation between BAX and DRP1 occurs exclusively in the membrane environment and requires the BAX N-terminal region, but also involves several other BAX surfaces. Furthermore, the association between BAX and DRP1 enhances the membrane activity of both proteins. Forced dimerization of BAX and DRP1 triggers their activation and translocation to mitochondria, where they induce mitochondrial remodeling and permeabilization to cause apoptosis even in the absence of apoptotic triggers. Based on this, we propose that DRP1 can promote apoptosis by acting as noncanonical direct activator of BAX through physical contacts with its N-terminal region.


Assuntos
Apoptose , Dinaminas , Apoptose/fisiologia , Dinaminas/genética , Dinaminas/metabolismo , Mitocôndrias/metabolismo , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
3.
Reprod Biomed Online ; 48(3): 103701, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38309124

RESUMO

RESEARCH QUESTION: Are basal FSH measurements, when elevated within its normal range, useful for assessing overall ovarian response and predicting unexpected poor or suboptimal ovarian response? DESIGN: Retrospective cohort study of ovarian stimulation cycles. RESULTS: A total of 1058 ovarian stimulation cycles (891 first, 167 repeated) were included. Anti-Müllerian hormone (AMH) values were categorized into four (0 to ≤0.6, >0.6 to ≤1.2, >1.2 to ≤3.0, >3.0 to ≤6.25 ng/ml) and basal FSH levels into four groups (<25th percentile: >3.5 to 6.1 IU/ml; 25-75th percentile: >6.1 to ≤8.5 IU/ml; >75-90th percentile: >8.5 to ≤9.9 IU/ml; >90th percentile: >9.9 to ≤12.5 IU/ml). Including only first cycles, a significant independent effect of basal FSH on retrieved cumulus-oocyte complex (COC) count was seen for all basal FSH categories (>90th, >75 to ≤90th, >25 to ≤75th compared with ≤25th percentile, P < 0.001, P = 0.001 and P = 0.007, respectively), when adjusted for age, body mass index (BMI), AMH, antral follicle count (AFC), starting dose and gonadotrophin type. Including only first cycles, patients aged 35 years or older with AFC of 5 or above and AMH 1.2 ng/ml or above, showed significantly higher odds of unexpected poor or suboptimal response if they had higher basal FSH values. Most prominently in the above 90th percentile group (OR 8.64, 95% CI 2.84 to 28.47 compared with <25th percentile) but lower categories (>25th to ≤75th percentile: OR 3.04, 95% CI 1.42 t 6.99; >75th to ≤90th percentile: OR 3.47, 95% CI 1.28 to 9.83 compared with ≤25th percentile) also showed a significant association after adjusting for age, AMH, BMI, AFC, dose, and gonadotrophin type. In patients with a second cycle, an increase in FSH levels in the second round compared with the first was associated with fewer retrieved COCs (estimate: -0.44, 95% CI -0.44 to -0.05, P = 0.027). This effect was adjusted for changes in age, FSH, AFC, starting dose, stimulation duration and change in medication type. CONCLUSIONS: Basal FSH is independently associated with overall ovarian response. Moreover, it is associated with unexpected poor or suboptimal response in patients, who would fulfill POSEIDON group 2 criteria after oocyte retrieval.


Assuntos
Fertilização in vitro , Reserva Ovariana , Feminino , Humanos , Reserva Ovariana/fisiologia , Estudos Retrospectivos , Resultado do Tratamento , Indução da Ovulação , Hormônio Foliculoestimulante , Hormônio Antimülleriano
4.
Reprod Biol Endocrinol ; 21(1): 47, 2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37202769

RESUMO

BACKGROUND: The key to optimal timing of frozen embryo transfer (FET ) is to synchronize the embryo with the receptive phase of the endometrium. Secretory transformation of the endometrium is induced by progesterone. In contrast, detection of the luteinizing hormone (LH) surge is the most common surrogate used to determine the start of secretory transformation and to schedule FET in a natural cycle. The accuracy of LH monitoring to schedule FET in a natural cycle relies heavily on the assumption that the period between the LH surge and ovulation is acceptably constant. This study will determine the period between LH rise and progesterone rise in ovulatory natural menstrual cycles. METHODS: Retrospective observational study including 102 women who underwent ultrasound and endocrine monitoring for a frozen embryo transfer in a natural cycle. All women had serum LH, estradiol and progesterone levels measured on three consecutive days until (including) the day of ovulation defined with serum progesterone level exceeding 1ng/ml. RESULTS: Twenty-one (20.6%) women had the LH rise 2 days prior to progesterone rise, 71 (69.6%) had on the day immediately preceding progesterone rise and 10 (9.8%) on the same day of progesterone rise. Women who had LH rise 2 days prior to progesterone rise had significantly higher body mass index and significantly lower serum AMH levels than women who had LH rise on the same day with progesterone rise. CONCLUSION: This study provides an unbiased account of the temporal relationship between LH and progesterone increase in a natural menstrual cycle. Variation in the period between LH rise and progesterone rise in ovulatory cycles likely has implications for the choice of marker for the start of secretory transformation in frozen embryo transfer cycles. The study participants are representative of the relevant population of women undergoing frozen embryo transfer in a natural cycle.


Assuntos
Medicina de Precisão , Progesterona , Feminino , Humanos , Masculino , Hormônio Luteinizante , Ciclo Menstrual , Transferência Embrionária
5.
Oecologia ; 203(1-2): 151-165, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37794240

RESUMO

Although it is well recognized that the strength of plant-herbivore interactions can vary with the plant sex, the distance, and the density of conspecific neighbors, no study has yet assessed their combined influence. Here, we filled this knowledge gap by focusing on the dioecious palm Chamaerops humilis L., and its two main herbivores, the invasive moth Paysandisia archon Burmeister and the feral goat Capra hircus L. We evaluated levels and spatial patterns of herbivory, as well as those of plant size and number of inflorescences in two palm populations in Mallorca (Balearic Islands, Spain). Our spatial point pattern analyses revealed that palms not affected by moth herbivory or goat florivory were spatially aggregated, goats fed more strongly upon inflorescences in palms with more neighbors, but they consumed more leaves in isolated palms. Interestingly, we could reveal for the first time that plant sex is a key plant trait modulating neighborhood effects. For instance, whereas aggregated female palms experienced lower intensity of goat florivory than isolated ones, male palms showed the opposite pattern. Palm size and number of inflorescences also showed sex-related differences, suggesting that sexual dimorphism is a key driver of the observed neighborhood effects on herbivory. Our study highlights the importance of considering relevant plant traits such as sex when investigating plant neighborhood effects, calling for further research to fully understand the dynamics governing plant-herbivore interactions in dioecious systems.


Assuntos
Arecaceae , Mariposas , Animais , Herbivoria , Folhas de Planta , Cabras , Características da Vizinhança
6.
Mol Cell ; 56(4): 496-505, 2014 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-25458844

RESUMO

Bax plays a central role in the mitochondrial pathway of apoptosis. Upon activation, cytosolic Bax monomers oligomerize on the surface of mitochondria and change conformation concertedly to punch holes into the outer membrane. The subsequent release of cytochrome c initiates cell death. However, the structure of membrane-inserted Bax and its mechanism of action remain largely unknown. Here, we propose a 3D model of active Bax at the membrane based on double electron-electron resonance (DEER) spectroscopy in liposomes and isolated mitochondria. We show that active Bax is organized at the membrane as assemblies of dimers. In addition to a stable dimerization domain, each monomer contains a more flexible piercing domain involved in interdimer interactions and pore formation. The most important structural change during Bax activation is the opening of the hairpin formed by helices 5 and 6, which adopts a clamp-like conformation central to the mechanism of mitochondrial permeabilization.


Assuntos
Membrana Celular/química , Proteína X Associada a bcl-2/química , Animais , Camundongos , Modelos Moleculares , Multimerização Proteica , Estrutura Quaternária de Proteína , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína
7.
Reprod Biomed Online ; 42(1): 66-74, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33189576

RESUMO

RESEARCH QUESTION: Is embryo selection by Dana (automatic software for embryo evaluation) associated with a higher implantation rate in IVF treatments? DESIGN: A three-phase study for Dana system's validation: creation of a data-cloud of known implantation data (KID) embryos from 1676 transferred embryos; embryo evaluation by Dana considering manual annotations and embryo development videos (389 transferred embryos); and validation of Dana automatic selection, without embryologist's intervention (147 transferred embryos); RESULTS: The implantation rate of the 1021 KID embryos from phase 1 served to set four grades of embryos referring to implantation rate: A = 34%, B = 25%, C = 24%, and D = 19%. Phase 2: a classification ranking according to the unit average distance (UAD) and implantation potential was established: top (UAD ≤0.50), high (UAD = 0.51-0.66), medium (UAD = 0.67-1.03) and low (UAD >1.03). Pregnancy rates were 59%, 46%, 36% and 28%, respectively (P < 0.001). Phase 3: embryos were automatically categorized according to Dana's classification ranking. Most implanted embryos were found in groups top, high and medium (UAD ≤1.03), whereas the implantation rate in group low (UAD >1.03) was significantly lower: 46% versus 25%, respectively (P = 0.037). The twin gestation rate was higher when number of top embryos (UAD ≤0.5) transferred were two (52%) versus one (25%) (P < 0.001). CONCLUSIONS: Embryo selection based on Dana ranking increases the success of IVF treatments at least in oocyte donation programmes. The multicentre nature of the study supports its applicability at different clinics, standardizing the embryo development's interpretation. Dana's innovation is that the system increases its accuracy as the database grows.


Assuntos
Blastocisto/classificação , Implantação do Embrião , Transferência Embrionária/estatística & dados numéricos , Taxa de Gravidez , Software , Adulto , Computação em Nuvem , Feminino , Humanos , Gravidez , Estudos Retrospectivos
8.
Reprod Biomed Online ; 42(2): 340-350, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33279421

RESUMO

RESEARCH QUESTION: The study aimed to develop an artificial intelligence model based on artificial neural networks (ANNs) to predict the likelihood of achieving a live birth using the proteomic profile of spent culture media and blastocyst morphology. DESIGN: This retrospective cohort study included 212 patients who underwent single blastocyst transfer at IVI Valencia. A single image of each of 186 embryos was studied, and the protein profile was analysed in 81 samples of spent embryo culture medium from patients included in the preimplantation genetic testing programme. The information extracted from the analyses was used as input data for the ANN. The multilayer perceptron and the back-propagation learning method were used to train the ANN. Finally, predictive power was measured using the area under the curve (AUC) of the receiver operating characteristic curve. RESULTS: Three ANN architectures classified most of the embryos correctly as leading (LB+) or not leading (LB-) to a live birth: 100.0% for ANN1 (morphological variables and two proteins), 85.7% for ANN2 (morphological variables and seven proteins), and 83.3% for ANN3 (morphological variables and 25 proteins). The artificial intelligence model using information extracted from blastocyst image analysis and concentrations of interleukin-6 and matrix metalloproteinase-1 was able to predict live birth with an AUC of 1.0. CONCLUSIONS: The model proposed in this preliminary report may provide a promising tool to select the embryo most likely to lead to a live birth in a euploid cohort. The accuracy of prediction demonstrated by this software may improve the efficacy of an assisted reproduction treatment by reducing the number of transfers per patient. Prospective studies are, however, needed.


Assuntos
Blastocisto/metabolismo , Nascido Vivo , Redes Neurais de Computação , Proteoma , Adulto , Blastocisto/citologia , Feminino , Humanos , Gravidez , Estudos Retrospectivos
9.
EMBO J ; 35(4): 389-401, 2016 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-26783362

RESUMO

Bax is a key regulator of apoptosis that, under cell stress, accumulates at mitochondria, where it oligomerizes to mediate the permeabilization of the mitochondrial outer membrane leading to cytochrome c release and cell death. However, the underlying mechanism behind Bax function remains poorly understood. Here, we studied the spatial organization of Bax in apoptotic cells using dual-color single-molecule localization-based super-resolution microscopy. We show that active Bax clustered into a broad distribution of distinct architectures, including full rings, as well as linear and arc-shaped oligomeric assemblies that localized in discrete foci along mitochondria. Remarkably, both rings and arcs assemblies of Bax perforated the membrane, as revealed by atomic force microscopy in lipid bilayers. Our data identify the supramolecular organization of Bax during apoptosis and support a molecular mechanism in which Bax fully or partially delineates pores of different sizes to permeabilize the mitochondrial outer membrane.


Assuntos
Apoptose , Mitocôndrias/enzimologia , Membranas Mitocondriais/metabolismo , Proteínas Citotóxicas Formadoras de Poros/metabolismo , Multimerização Proteica , Proteína X Associada a bcl-2/metabolismo , Citocromos c/metabolismo , Células HeLa , Humanos , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Membranas Mitocondriais/fisiologia , Permeabilidade
10.
Sensors (Basel) ; 20(9)2020 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-32354094

RESUMO

During university studies of nursing, it is important to develop emotional skills for their impact on academic performance and the quality of patient care. Thermography is a technology that could be applied during nursing training to evaluate emotional skills. The objective is to evaluate the effect of thermography as the tool for monitoring and improving emotional skills in student nurses through a case study. The student was subjected to different emotions. The stimuli applied were video and music. The process consisted of measuring the facial temperatures during each emotion and stimulus in three phases: acclimatization, stimulus, and response. Thermographic data acquisition was performed with an FLIR E6 camera. The analysis was complemented with the environmental data (temperature and humidity). With the video stimulus, the start and final forehead temperature from testing phases, showed a different behavior between the positive (joy: 34.5 °C-34.5 °C) and negative (anger: 36.1 °C-35.1 °C) emotions during the acclimatization phase, different from the increase experienced in the stimulus (joy: 34.7 °C-35.0 °C and anger: 35.0 °C-35.0 °C) and response phases (joy: 35.0 °C-35.0 °C and anger: 34.8 °C-35.0 °C). With the music stimulus, the emotions showed different patterns in each phase (joy: 34.2 °C-33.9 °C-33.4 °C and anger: 33.8 °C-33.4 °C-33.8 °C). Whenever the subject is exposed to a stimulus, there is a thermal bodily response. All of the facial areas follow a common thermal pattern in response to the stimulus, with the exception of the nose. Thermography is a technique suitable for the stimulation practices in emotional skills, given that it is non-invasive, it is quantifiable, and easy to access.


Assuntos
Educação em Enfermagem/métodos , Emoções/fisiologia , Estudantes de Enfermagem/psicologia , Termografia/métodos , Adulto , Feminino , Humanos
11.
Biol Reprod ; 101(6): 1146-1154, 2019 12 24.
Artigo em Inglês | MEDLINE | ID: mdl-30810735

RESUMO

The introduction of time-lapse imaging to clinical in vitro fertilization practice enabled the undisturbed monitoring of embryos throughout the entire culture period. Initially, the main objective was to achieve a better embryo development. However, this technology also provided an insight into the novel concept of morphokinetics, parameters regarding embryo cell dynamics. The vast amount of data obtained defined the optimal ranges in the cell-cycle lengths at different stages of embryo development. This added valuable information to embryo assessment prior to transfer. Kinetic markers became part of embryo evaluation strategies with the potential to increase the chances of clinical success. However, none of them has been established as an international standard. The present work aims at describing new approaches into time-lapse: progress to date, challenges, and possible future directions.


Assuntos
Fertilização in vitro/métodos , Imagem com Lapso de Tempo/métodos , Algoritmos , Aneuploidia , Blastocisto/citologia , Técnicas de Cultura Embrionária , Implantação do Embrião , Desenvolvimento Embrionário , Feminino , Humanos , Cinética , Masculino , Medicina de Precisão , Gravidez , Taxa de Gravidez , Segurança
12.
BMC Cancer ; 16: 680, 2016 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-27558259

RESUMO

BACKGROUND: Galectin-7 (Gal-7) is negatively regulated in cervical cancer, and appears to be a link between the apoptotic response triggered by cancer and the anti-tumoral activity of the immune system. Our understanding of how cervical cancer cells and their molecular networks adapt in response to the expression of Gal-7 remains limited. METHODS: Meta-analysis of Gal-7 expression was conducted in three cervical cancer cohort studies and TCGA. In silico prediction and bisulfite sequencing were performed to inquire epigenetic alterations. To study the effect of Gal-7 on cervical cancer, we ectopically re-expressed it in the HeLa and SiHa cervical cancer cell lines, and analyzed their transcriptome and SILAC-based proteome. We also examined the tumor and microenvironment host cell transcriptomes after xenotransplantation into immunocompromised mice. Differences between samples were assessed with the Kruskall-Wallis, Dunn's Multiple Comparison and T tests. Kaplan-Meier and log-rank tests were used to determine overall survival. RESULTS: Gal-7 was constantly downregulated in our meta-analysis (p < 0.0001). Tumors with combined high Gal-7 and low galectin-1 expression (p = 0.0001) presented significantly better prognoses (p = 0.005). In silico and bisulfite sequencing assays showed de novo methylation in the Gal-7 promoter and first intron. Cells re-expressing Gal-7 showed a high apoptosis ratio (p < 0.05) and their xenografts displayed strong growth retardation (p < 0.001). Multiple gene modules and transcriptional regulators were modulated in response to Gal-7 reconstitution, both in cervical cancer cells and their microenvironments (FDR < 0.05 %). Most of these genes and modules were associated with tissue morphogenesis, metabolism, transport, chemokine activity, and immune response. These functional modules could exert the same effects in vitro and in vivo, even despite different compositions between HeLa and SiHa samples. CONCLUSIONS: Gal-7 re-expression affects the regulation of molecular networks in cervical cancer that are involved in diverse cancer hallmarks, such as metabolism, growth control, invasion and evasion of apoptosis. The effect of Gal-7 extends to the microenvironment, where networks involved in its configuration and in immune surveillance are particularly affected.


Assuntos
Galectinas/metabolismo , Microambiente Tumoral/fisiologia , Neoplasias do Colo do Útero/metabolismo , Feminino , Humanos , Neoplasias do Colo do Útero/patologia
13.
Commun Biol ; 6(1): 962, 2023 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-37735514

RESUMO

BRAF mutations occur early in serrated colorectal cancers, but their long-term influence on tissue homeostasis is poorly characterized. We investigated the impact of short-term (3 days) and long-term (6 months) expression of BrafV600E in the intestinal tissue of an inducible mouse model. We show that BrafV600E perturbs the homeostasis of intestinal epithelial cells, with impaired differentiation of enterocytes emerging after prolonged expression of the oncogene. Moreover, BrafV600E leads to a persistent transcriptional reprogramming with enrichment of numerous gene signatures indicative of proliferation and tumorigenesis, and signatures suggestive of metabolic rewiring. We focused on the top-ranking cholesterol biosynthesis signature and confirmed its increased expression in human serrated lesions. Functionally, the cholesterol lowering drug atorvastatin prevents the establishment of intestinal crypt hyperplasia in BrafV600E-mutant mice. Overall, our work unveils the long-term impact of BrafV600E expression in intestinal tissue and suggests that colorectal cancers with mutations in BRAF might be prevented by statins.


Assuntos
Neoplasias Colorretais , Proteínas Proto-Oncogênicas B-raf , Animais , Humanos , Camundongos , Colesterol , Neoplasias Colorretais/genética , Metabolismo dos Lipídeos , Proteínas Proto-Oncogênicas B-raf/genética , Ativação Transcricional
14.
Ecology ; 103(11): e3797, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35724972

RESUMO

Plant-animal interactions fall within a mutualism-antagonism continuum, exerting a wide range of effects on plant reproductive success. These effects become even more complex and diverse when several disparate animal species interact with the same plant species. Despite the increasing number of studies about the influence of herbivory on plant performance, the outcomes mediated by pollination and the combined impact of multiple herbivores on pollination-specialized plants are underexplored. In this study, we chose the Mediterranean dwarf palm Chamaerops humilis (Arecaceae) to illustrate the isolated and joint effect of two contrasting introduced herbivores, the palm borer Paysandisia archon (Lepidoptera, Castniidae) and feral goats, on pollinator abundance and plant reproductive success. To this aim, we monitored moth herbivory and goat herbivory in four palm populations in Mallorca (Balearic Islands) during 2019 and 2020. The effect of herbivory varied widely depending on both the herbivore and the pollinator species. Moth herbivory had a positive effect on pollinator abundance and fruit initiation, whereas goat herbivory had a negative effect on inflorescence production, pollinator abundance and fruit initiation. In addition, both herbivores exerted unexpected nonadditive effects on palm reproduction. Palms attacked by both herbivore species produced many more inflorescences (up to 18-fold) but had a lower fruit initiation success (close to zero) than unattacked palms or those attacked by a single herbivore species. Interestingly, only one of the two main pollinator species (the nitidulid beetle Meligethinus pallidulus) was impacted by herbivory. Our study highlights the need to investigate the possible nonadditive effects of all coexisting herbivores on plant performance, especially when establishing conservation plans and pest control strategies.


Assuntos
Arecaceae , Herbivoria , Animais , Besouros , Cabras , Polinização , Reprodução
15.
PLoS One ; 17(2): e0262364, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35130302

RESUMO

Research into the metabolism of the non-essential amino acid (NEAA) proline in cancer has gained traction in recent years. The last step in the proline biosynthesis pathway is catalyzed by pyrroline-5-carboxylate reductase (PYCR) enzymes. There are three PYCR enzymes: mitochondrial PYCR1 and 2 and cytosolic PYCR3 encoded by separate genes. The expression of the PYCR1 gene is increased in numerous malignancies and correlates with poor prognosis. PYCR1 expression sustains cancer cells' proliferation and survival and several mechanisms have been implicated to explain its oncogenic role. It has been suggested that the biosynthesis of proline is key to sustain protein synthesis, support mitochondrial function and nucleotide biosynthesis. However, the links between proline metabolism and cancer remain ill-defined and are likely to be tissue specific. Here we use a combination of human dataset, human tissue and mouse models to show that the expression levels of the proline biosynthesis enzymes are significantly increased during colorectal tumorigenesis. Functionally, the expression of mitochondrial PYCRs is necessary for cancer cells' survival and proliferation. However, the phenotypic consequences of PYCRs depletion could not be rescued by external supplementation with either proline or nucleotides. Overall, our data suggest that, despite the mechanisms underlying the role of proline metabolism in colorectal tumorigenesis remain elusive, targeting the proline biosynthesis pathway is a suitable approach for the development of novel anti-cancer therapies.


Assuntos
Neoplasias Colorretais
16.
Front Psychol ; 11: 573728, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33324287

RESUMO

Adolescent-to-Parent Violence (APV) or Child-to-Parent Violence (CPV) is a specific form of violence that has remained inconspicuous until recently, but is becoming a mounting social issue and is increasingly the focus of scientific research. Of the variables related to APV, the study assessed the characteristics of the family system and its relationship to the psychosocial adjustment of adolescents, an aspect scarcely examined in the literature. Thus, a field study was performed on a community sample of 210 adolescents aged 12-17 years (51.4% girls) who were assessed on measurements of APV, parenting (parental socialization), victimization, and psychological adjustment (personal, family, and school). The results revealed higher rates of psychological APV, and no gender effects in violence exercised against either parent. The adolescents involved in APV exhibited a greater psychological maladjustment in the different areas under analysis. Moreover, adolescents engaging in psychological APV reported a parental socialization style characterized by severe strictness and supervision in comparison to non-aggressors not implicated in psychological APV. Finally, adolescents exercising APV who were victimized by their parents showed more psychological, personal, and school maladjustment. These results have implications for needs analysis and the planning of community prevention strategies.

17.
Cell Death Discov ; 6: 104, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33083024

RESUMO

The metabolism of the non-essential amino acid L-proline is emerging as a key pathway in the metabolic rewiring that sustains cancer cells proliferation, survival and metastatic spread. Pyrroline-5-carboxylate reductase (PYCR) and proline dehydrogenase (PRODH) enzymes, which catalyze the last step in proline biosynthesis and the first step of its catabolism, respectively, have been extensively associated with the progression of several malignancies, and have been exposed as potential targets for anticancer drug development. As investigations into the links between proline metabolism and cancer accumulate, the complexity, and sometimes contradictory nature of this interaction emerge. It is clear that the role of proline metabolism enzymes in cancer depends on tumor type, with different cancers and cancer-related phenotypes displaying different dependencies on these enzymes. Unexpectedly, the outcome of rewiring proline metabolism also differs between conditions of nutrient and oxygen limitation. Here, we provide a comprehensive review of proline metabolism in cancer; we collate the experimental evidence that links proline metabolism with the different aspects of cancer progression and critically discuss the potential mechanisms involved.

18.
Biology (Basel) ; 9(9)2020 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-32961716

RESUMO

The use of cooled semen is relatively common in goats. There are a number of advantages of cooled semen doses, including easier handling of artificial insemination (AI) doses, transport, more AI doses per ejaculate, and higher fertility rates in comparison with frozen AI doses. However, cooled semen has a short shelf life. The objective of this study was to examine the effect of temperature and sperm concentration on the in vitro sperm quality during liquid storage for 48 h, including sperm motility and kinetics, response to oxidation, mitochondrial membrane potential (MMP) and DNA fragmentation in goats. Three experiments were performed. In the first, the effects of liquid preservation of semen at different temperatures (5 °C or 17 °C), durations (0, 24 and 48 h) and sperm concentrations (250 × 106 sperm/mL (1:2 dilution rate), 166.7 × 106 sperm/mL (1:3 dilution rate) or 50 × 106 sperm/mL (1:10 dilution rate)) on sperm motility and kinetics were studied. In the second experiment, the effect of temperature, sperm washing and concentration on sperm motility and DNA fragmentation was studied. Finally, the effect of sperm concentration and duration of storage at 5 °C on sperm motility, response to oxidative stress and MMP was examined. We found that refrigerated liquid storage of goat sperm impaired sperm quality, such as motility, MMP and response to oxidation, as storage time increased; however, sperm DNA fragmentation index was not significantly affected. Liquid storage at 5 °C preserved higher total motility than at 17 °C. Moreover, we observed that the reduction of sperm concentration below 500 × 106 sperm/mL did not seem to improve the quality of spermatozoa conserved in milk-based extender in the conditions tested.

19.
Br J Nutr ; 101(5): 750-9, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18680629

RESUMO

Controlled human intervention trials are required to confirm the hypothesis that dietary fat quality may influence insulin action. The aim was to develop a food-exchange model, suitable for use in free-living volunteers, to investigate the effects of four experimental diets distinct in fat quantity and quality: high SFA (HSFA); high MUFA (HMUFA) and two low-fat (LF) diets, one supplemented with 1.24 g EPA and DHA/d (LFn-3). A theoretical food-exchange model was developed. The average quantity of exchangeable fat was calculated as the sum of fat provided by added fats (spreads and oils), milk, cheese, biscuits, cakes, buns and pastries using data from the National Diet and Nutrition Survey of UK adults. Most of the exchangeable fat was replaced by specifically designed study foods. Also critical to the model was the use of carbohydrate exchanges to ensure the diets were isoenergetic. Volunteers from eight centres across Europe completed the dietary intervention. Results indicated that compositional targets were largely achieved with significant differences in fat quantity between the high-fat diets (39.9 (sem 0.6) and 38.9 (sem 0.51) percentage energy (%E) from fat for the HSFA and HMUFA diets respectively) and the low-fat diets (29.6 (sem 0.6) and 29.1 (sem 0.5) %E from fat for the LF and LFn-3 diets respectively) and fat quality (17.5 (sem 0.3) and 10.4 (sem 0.2) %E from SFA and 12.7 (sem 0.3) and 18.7 (sem 0.4) %E MUFA for the HSFA and HMUFA diets respectively). In conclusion, a robust, flexible food-exchange model was developed and implemented successfully in the LIPGENE dietary intervention trial.


Assuntos
Gorduras na Dieta/administração & dosagem , Síndrome Metabólica/dietoterapia , Adulto , Idoso , Dieta/estatística & dados numéricos , Inquéritos sobre Dietas , Dieta com Restrição de Gorduras , Ácidos Docosa-Hexaenoicos/administração & dosagem , Ácido Eicosapentaenoico/administração & dosagem , Ácidos Graxos/administração & dosagem , Ácidos Graxos Monoinsaturados/administração & dosagem , Comportamento Alimentar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Cooperação do Paciente , Educação de Pacientes como Assunto/métodos , Adulto Jovem
20.
Fertil Steril ; 111(5): 918-927.e3, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30922642

RESUMO

OBJECTIVE: To develop a noninvasive embryo selection algorithm consisting of time-lapse morphokinetics and the oxidative status of the spent embryo culture medium determined using the Thermochemiluminescence (TCL) Analyzer. DESIGN: Retrospective cohort. SETTING: Not applicable. PATIENT(S): From women participating in the oocyte donation program, data from 505 samples of spent embryo culture media samples from 292 intracytoplasmic sperm injection cycles. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Morphokinetic parameters assessed during incubation in the time-lapse system Embryoscope. Oxidative parameters (H1sm, H2sm, and H3sm) from the spent culture medium on day 5 of incubation measured using the TCL assay; and a combined assessment algorithm, including morphology, morphokinetics, and the embryo's culture medium oxidative status, developed as a tool for embryo selection, based on implantation success and confirmed ongoing pregnancy. RESULT(S): The levels of the oxidative parameters H1sm, H2sm, and H3sm on day 5 of incubation were statistically significantly higher in transferred and vitrified embryos compared with discarded embryos and in successfully implanted embryos compared with those that did not result in pregnancy. The assessment algorithm resulted in a hierarchical classification with six embryo quality categories (A to F), associated with implantation rates of between 76.5% and 29.2%. CONCLUSION(S): An assessment algorithm combining morphology, morphokinetics and the embryo's culture medium oxidative status may help to improve current embryo selection methods criteria and in vitro fertilization success.


Assuntos
Algoritmos , Meios de Cultura/análise , Técnicas de Cultura Embrionária/métodos , Transferência Embrionária/métodos , Estresse Oxidativo/fisiologia , Imagem com Lapso de Tempo/métodos , Adulto , Estudos de Coortes , Feminino , Humanos , Cinética , Gravidez , Estudos Retrospectivos
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa