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1.
Cell ; 186(15): 3166-3181.e18, 2023 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-37413989

RESUMEN

Proper preimplantation development is essential to assemble a blastocyst capable of implantation. Live imaging has uncovered major events driving early development in mouse embryos; yet, studies in humans have been limited by restrictions on genetic manipulation and lack of imaging approaches. We have overcome this barrier by combining fluorescent dyes with live imaging to reveal the dynamics of chromosome segregation, compaction, polarization, blastocyst formation, and hatching in the human embryo. We also show that blastocyst expansion mechanically constrains trophectoderm cells, causing nuclear budding and DNA shedding into the cytoplasm. Furthermore, cells with lower perinuclear keratin levels are more prone to undergo DNA loss. Moreover, applying trophectoderm biopsy, a mechanical procedure performed clinically for genetic testing, increases DNA shedding. Thus, our work reveals distinct processes underlying human development compared with mouse and suggests that aneuploidies in human embryos may not only originate from chromosome segregation errors during mitosis but also from nuclear DNA shedding.


Asunto(s)
Diagnóstico Preimplantación , Embarazo , Femenino , Humanos , Animales , Ratones , Diagnóstico Preimplantación/métodos , Blastocisto , Implantación del Embrión , Pruebas Genéticas/métodos , Aneuploidia , Biopsia/métodos
2.
Bioinformatics ; 39(10)2023 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-37756698

RESUMEN

MOTIVATION: Biological network analysis for high-throughput biomedical data interpretation relies heavily on topological characteristics. Networks are commonly composed of nodes representing genes or proteins that are connected by edges when interacting. In this study, we use the rich information available in the Reactome pathway database to build biological networks accounting for small molecules and proteoforms modeled using protein isoforms and post-translational modifications to study the topological changes induced by this refinement of the network representation. RESULTS: We find that improving the interactome modeling increases the number of nodes and interactions, but that isoform and post-translational modification annotation is still limited compared to what can be expected biologically. We also note that small molecule information can distort the topology of the network due to the high connectedness of these molecules, which does not necessarily represent the reality of biology. However, by restricting the connections of small molecules to the context of biochemical reactions, we find that these improve the overall connectedness of the network and reduce the prevalence of isolated components and nodes. Overall, changing the representation of the network alters the prevalence of articulation points and bridges globally but also within and across pathways. Hence, some molecules can gain or lose in biological importance depending on the level of detail of the representation of the biological system, which might in turn impact network-based studies of diseases or druggability. AVAILABILITY AND IMPLEMENTATION: Networks are constructed based on data publicly available in the Reactome Pathway knowledgebase: reactome.org.

3.
New Phytol ; 242(5): 2026-2042, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38494681

RESUMEN

Seed dormancy governs germination timing, with both evolutionary and applied consequences. Despite extensive studies on the hormonal and genetic control of these processes, molecular mechanisms directly linking dormancy and germination remain poorly understood. By screening a collection of lines overexpressing Arabidopsis transcription factors, we identified ERF50 as a key gene to control dormancy and germination. To study its regulation, we measured seed-related physiological parameters in loss-of-function mutants and carried out transactivation, protein interaction and ChIP-PCR analyses. We found direct ERF50-mediated repression of DOG1 and activation of EXPA2 transcription, which results in enhanced seed germination. Although ERF50 expression is increased by DOG1 in dormant seeds, ERF50 germination-promoting activity is blocked by RGL2. The physiological, genetic and molecular evidence gathered here supports that ERF50 controls germination timing by regulating DOG1 levels to leverage its role as enhancer of seed germination, via RGL2 antagonism on EXPA2 expression. Our results highlight the central role of ERF50 as a feedback regulator to couple and fine-tune seed dormancy and germination.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Retroalimentación Fisiológica , Regulación de la Expresión Génica de las Plantas , Germinación , Latencia en las Plantas , Semillas , Factores de Transcripción , Germinación/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Arabidopsis/genética , Arabidopsis/fisiología , Arabidopsis/crecimiento & desarrollo , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Semillas/crecimiento & desarrollo , Semillas/fisiología , Semillas/genética , Latencia en las Plantas/genética , Factores de Tiempo , Unión Proteica
4.
Chemistry ; 30(31): e202400379, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38525912

RESUMEN

Different approaches to achieve 2D supramolecular polymers, as an alternative to the covalent bottom-up approaches reported for the preparation of 2D materials, are reviewed. The significance of the operation of weak non-covalent forces to induce a lateral growth of a number of self-assembling units is collected. The examples of both thermodynamically and kinetically controlled formation of 2D supramolecular polymers showed in this review demonstrate the utility of this strategy to achieve new 2D materials with biased morphologies (nanosheets, scrolls, porous surfaces) and showing elegant applications like chiral recognition, enantioselective uptake or asymmetric organic transformations. Furthermore, elaborated techniques like seeded or living supramolecular polymerizations have been demonstrated to give rise to complex 2D nanostructures.

5.
J Nutr ; 154(3): 866-874, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38219862

RESUMEN

BACKGROUND: Bifidobacterium animalis ssp. lactis DN-173 010/CNCM I-2494 (B. animalis) is a probiotic strain commonly added to yogurt. Yogurt and honey are a popular culinary pairing. Honey improves bifidobacteria survival in vitro. However, probiotic survival in yogurt with honey during in vitro digestion has not been investigated. OBJECTIVES: The study aimed to evaluate the effects of different honey varietals and concentrations on B. animalis survivability in yogurt through in vitro digestion. METHODS: Yogurt with honey or control-treated samples underwent in vitro simulated oral, gastric, and intestinal digestion. B. animalis cells were enumerated on de Man Rogosa and Sharpe (MRS) medium followed by an overlay with a modified selective MRS medium; all underwent anaerobic incubation. B. animalis were enumerated predigestion and after oral, gastric, and intestinal digestion. There were 2 study phases: Phase 1 tested 4 honey varietals at 20% wt/wt per 170 g yogurt, and Phase 2 tested 7 dosages of clover honey (20, 14, 10, 9, 8, 6, and 4% wt/wt) per 170 g yogurt. RESULTS: Similar B. animalis counts were observed between all treatments after oral and gastric digestion (<1 Log colony forming units (CFU)/g probiotic reduction). Higher B. animalis survivability was observed in yogurt with clover honey after exposure to simulated intestinal fluids (∼3.5 Log CFU/g reduction; P < 0.05) compared to all control treatments (∼5.5 Log CFU/g reduction; P < 0.05). Yogurt with 10-20% wt/wt clover honey increased B. animalis survivability after simulated in vitro digestion (≤ ∼4.7 Log CFU/g survival; P < 0.05). CONCLUSIONS: Yogurt with added honey improves probiotic survivability during in vitro digestion. The effective dose of clover honey in yogurt was 10-20% wt/wt per serving (1-2 tablespoons per 170 g yogurt) for increased probiotic survivability during in vitro digestion.


Asunto(s)
Bifidobacterium animalis , Miel , Probióticos , Humanos , Yogur/microbiología , Bifidobacterium , Probióticos/uso terapéutico , Digestión
6.
Eur J Neurol ; 31(2): e16112, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37909802

RESUMEN

BACKGROUND AND PURPOSE: In patients with acute ischaemic stroke (AIS), haemorrhagic transformation (HT) following endovascular treatment (EVT) is associated with poor functional outcome. However, the impact of asymptomatic HT, not linked to neurological deterioration in the acute phase, is unknown. We aimed to investigate the impact of asymptomatic PH1 (aPH1) and PH2 (aPH2) subtypes of HT on the functional outcome of patients treated with EVT. METHODS: We conducted a retrospective study of patients with AIS who were consecutively admitted to our comprehensive stroke centre between January 2019 and December 2022, and who underwent EVT. We collected clinical, radiological, and procedural data. HTs were categorized according to the Heidelberg classification. The primary outcome was the shift on the modified Rankin Scale (mRS) at 3 months of follow-up. We performed bivariate and multivariable ordinal regression analyses to test the association between aPH1/aPH2 and the primary outcome. RESULTS: We included 314 patients (mean age = 72.5 years [SD = 13.6], 171 [54.5%] women). We detected 54 (17.2%) patients with HT; 23 (7.3%) were classified as PH2 (11 asymptomatic) and 17 (5.4%) as PH1 (16 asymptomatic). The adjusted common odds ratio for aPH2 of worsening 1 point on the 3-month mRS was 3.32 (95% confidence interval = 1.16-9.57, p = 0.026). No association was observed for aPH1. aPH2 was also independently associated with lower odds of achieving a favourable outcome (mRS = 0-2). Neither aPH1 nor aPH2 was associated with mortality. CONCLUSIONS: In patients with AIS treated with EVT, aPH2 is independently associated with unfavourable functional outcome.


Asunto(s)
Isquemia Encefálica , Procedimientos Endovasculares , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Femenino , Anciano , Masculino , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/cirugía , Isquemia Encefálica/complicaciones , Isquemia Encefálica/cirugía , Estudios Retrospectivos , Accidente Cerebrovascular Isquémico/complicaciones , Hemorragia/etiología , Procedimientos Endovasculares/efectos adversos , Resultado del Tratamiento , Trombectomía
7.
Biol Cell ; 115(3): e2200046, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36571578

RESUMEN

BACKGROUND INFORMATION: Autophagy is a conserved process that functions as a cytoprotective mechanism; it may function as a cell death process called programmed cell death type II. There is considerable evidence for the presence of autophagic cell death during oocyte elimination in prepubertal rats. However, the mechanisms involved in this process have not been deciphered. RESULTS: Our observations revealed autophagic cell death in oocytes with increased labeling of the autophagic proteins Beclin 1, light chain 3 A (LC3 A), and lysosomal-associated membrane protein 1 (Lamp1). Furthermore, mTOR and phosphorylated (p)-mTOR (S2448) proteins were significantly decreased in oocytes with increased levels of autophagic proteins, indicating autophagic activation. Moreover, phosphorylated protein kinase B (p-AKT) was not expressed by oocytes, but mitogen-activated protein kinase/extracellular signalregulated kinase (MAPK/ERK) signaling was observed. Additionally, selective and elevated mitochondrial degradation was identified in altered oocytes. CONCLUSIONS: All these results suggest that mTOR downregulation, which promotes autophagy, could be mediated by low energy levels and sustained starvation involving the phosphoinositide 3-kinase (PI3K)/AKT/mTOR and MAPK/ERK pathways. SIGNIFICANCE: In this work, we analyzed the manner in which autophagy is carried out in oocytes undergoing autophagic cell death by studying the behavior of proteins involved in different steps of the autophagic pathway.


Asunto(s)
Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Femenino , Ratas , Animales , Proteínas Proto-Oncogénicas c-akt/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Folículo Ovárico/metabolismo , Oocitos/metabolismo , Autofagia
8.
Chirality ; 36(2): e23639, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38384148

RESUMEN

Herein, the synthesis of two chiral NPBIs, (S)-1 and (R)-1, is reported and their self-assembling features investigated. The reported NPBIs form chiral supramolecular polymers with a rich dichroic pattern by the π-stacking of the aromatic backbones and the formation of an array of H-bonds between the amide functional groups. Furthermore, the peripheral 3,4,5-trialkoxy benzamide groups can form seven-membered pseudocycles by the intramolecular H-bonding interaction between the NH of the peripheral amides and one of the carbonyls of the imide units thus yielding a kinetically controlled self-assembly process. Unlike achiral NPBI 1, that has been reported to form up to four supramolecular polymorphs, the reported chiral NPBIs form only a J-type aggregated species. The results presented herein reveal how subtle changes exert an enormous influence on the supramolecular polymerization outcome.

9.
Eur J Public Health ; 34(1): 44-51, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-37875008

RESUMEN

BACKGROUND: Value-based healthcare (VBHC) is a conceptual framework to improve the value of healthcare by health, care-process and economic outcomes. Benchmarking should provide useful information to identify best practices and therefore a good instrument to improve quality across healthcare organizations. This paper aims to provide a proof-of-concept of the feasibility of an international VBHC benchmarking in breast cancer, with the ultimate aim of being used to share best practices with a data-driven approach among healthcare organizations from different health systems. METHODS: In the VOICE community-a European healthcare centre cluster intending to address VBHC from theory to practice-information on patient-reported, clinical-related, care-process-related and economic-related outcomes were collected. Patient archetypes were identified using clustering techniques and an indicator set following a modified Delphi was defined. Benchmarking was performed using regression models controlling for patient archetypes and socio-demographic characteristics. RESULTS: Six hundred and ninety patients from six healthcare centres were included. A set of 50 health, care-process and economic indicators was distilled for benchmarking. Statistically significant differences across sites have been found in most health outcomes, half of the care-process indicators, and all economic indicators, allowing for identifying the best and worst performers. CONCLUSIONS: To the best of our knowledge, this is the first international experience providing evidence to be used with VBHC benchmarking intention. Differences in indicators across healthcare centres should be used to identify best practices and improve healthcare quality following further research. Applied methods might help to move forward with VBHC benchmarking in other medical conditions.


Asunto(s)
Benchmarking , Calidad de la Atención de Salud , Humanos , Benchmarking/métodos , Atención a la Salud
10.
Proc Natl Acad Sci U S A ; 118(35)2021 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-34446553

RESUMEN

Polychlorinated biphenyls (PCBs) are persistent organic pollutants with severe effects on human health and the biosphere. Plant-based remediation offers many benefits over conventional PCB remediation, but its development has been hampered by our poor understanding of biphenyl metabolism in eukaryotes, among other factors. We report here a major PCB-responsive protein in poplar, a plant model system capable of PCB uptake and translocation. We provide structural and functional evidence that this uncharacterized protein, termed SDR57C, belongs to the heterogeneous short-chain dehydrogenase reductase (SDR) superfamily. Despite sequence divergence, structural modeling hinted at structural and functional similarities between SDR57C and BphB, a central component of the Bph pathway for biphenyl/PCB degradation in aerobic bacteria. By combining gas chromatography/mass spectrometry (GC/MS) profiling with a functional complementation scheme, we found that poplar SDR57C can replace BphB activity in the upper Bph pathway of Pseudomonas furukawaii KF707 and therefore catalyze the oxidation of 2,3-dihydro-2,3-dihydroxybiphenyl (2,3-DHDB) to 2,3-dihydroxybiphenyl (2,3-DHB). Consistent with this biochemical activity, we propose a mechanism of action based on prior quantum studies, general properties of SDR enzymes, and the modeled docking of 2,3-DHDB to the SDR57C-NAD+ complex. The putative detoxifying capacity of SDR57C was substantiated through reverse genetics in Arabidopsis thaliana Phenotypic characterization of the SDR lines underscored an inducible plant pathway with the potential to catabolize toxic biphenyl derivatives. Partial similarities with aerobic bacterial degradation notwithstanding, real-time messenger RNA quantification indicates the occurrence of plant-specific enzymes and features. Our results may help explain differences in degradative abilities among plant genotypes and also provide elements to improve them.


Asunto(s)
Arabidopsis/efectos de los fármacos , Biodegradación Ambiental , Proteínas de Plantas/metabolismo , Bifenilos Policlorados/metabolismo , Populus/enzimología , Pseudomonas/fisiología , Deshidrogenasas-Reductasas de Cadena Corta/metabolismo , Arabidopsis/crecimiento & desarrollo , Arabidopsis/microbiología , Proteínas de Plantas/genética , Deshidrogenasas-Reductasas de Cadena Corta/genética
11.
Chem Soc Rev ; 52(21): 7524-7548, 2023 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-37819705

RESUMEN

As an active branch within the field of supramolecular polymers, chiral supramolecular polymers (SPs) are an excellent benchmark to generate helical structures that can clarify the origin of homochirality in Nature or help determine new exciting functionalities of organic materials. Herein, we highlight the most utilized strategies to build up chiral SPs by using chiral monomeric units or external stimuli. Selected examples of transfer of asymmetry, in which the point or axial chirality contained by the monomeric units is efficiently transferred to the supramolecular scaffold yielding enantioenriched helical structures, will be presented. The importance of the thermodynamics and kinetics associated with those processes is stressed, especially the influence that parameters such as the helix reversal and mismatch penalties exert on the achievement of amplification of asymmetry in co-assembled systems will also be considered. Remarkable examples of breaking symmetry, in which chiral supramolecular polymers can be attained from achiral self-assembling units by applying external stimuli like stirring, solvent or light, are highlighted. Finally, the specific and promising applications of chiral supramolecular polymers are presented with recent relevant examples.

12.
Sensors (Basel) ; 24(5)2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38475231

RESUMEN

Nowadays, there are plenty of data sources generating massive amounts of information that, combined with novel data analytics frameworks, are meant to support optimisation in many application domains. Nonetheless, there are still shortcomings in terms of data discoverability, accessibility and interoperability. Open Data portals have emerged as a shift towards openness and discoverability. However, they do not impose any condition to the data itself, just stipulate how datasets have to be described. Alternatively, the NGSI-LD standard pursues harmonisation in terms of data modelling and accessibility. This paper presents a solution that bridges these two domains (i.e., Open Data portals and NGSI-LD-based data) in order to keep benefiting from the structured description of datasets offered by Open Data portals, while ensuring the interoperability provided by the NGSI-LD standard. Our solution aggregates the data into coherent datasets and generate high-quality descriptions, ensuring comprehensiveness, interoperability and accessibility. The proposed solution has been validated through a real-world implementation that exposes IoT data in NGSI-LD format through the European Data Portal (EDP). Moreover, the results from the Metadata Quality Assessment that the EDP implements, show that the datasets' descriptions generated achieve excellent ranking in terms of the Findability, Accessibility, Interoperability and Reusability (FAIR) data principles.

13.
Sensors (Basel) ; 24(6)2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38544121

RESUMEN

The vast amount of information stemming from the deployment of the Internet of Things and open data portals is poised to provide significant benefits for both the private and public sectors, such as the development of value-added services or an increase in the efficiency of public services. This is further enhanced due to the potential of semantic information models such as NGSI-LD, which enable the enrichment and linkage of semantic data, strengthened by the contextual information present by definition. In this scenario, advanced data processing techniques need to be defined and developed for the processing of harmonised datasets and data streams. Our work is based on a structured approach that leverages the principles of linked-data modelling and semantics, as well as a data enrichment toolchain framework developed around NGSI-LD. Within this framework, we reveal the potential for enrichment and linkage techniques to reshape how data are exploited in smart cities, with a particular focus on citizen-centred initiatives. Moreover, we showcase the effectiveness of these data processing techniques through specific examples of entity transformations. The findings, which focus on improving data comprehension and bolstering smart city advancements, set the stage for the future exploration and refinement of the symbiosis between semantic data and smart city ecosystems.

14.
Biol Sport ; 41(2): 221-241, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38524814

RESUMEN

The rise of artificial intelligence (AI) applications in healthcare provides new possibilities for personalized health management. AI-based fitness applications are becoming more common, facilitating the opportunity for individualised exercise prescription. However, the use of AI carries the risk of inadequate expert supervision, and the efficacy and validity of such applications have not been thoroughly investigated, particularly in the context of diverse health conditions. The aim of the study was to critically assess the efficacy of exercise prescriptions generated by OpenAI's Generative Pre-Trained Transformer 4 (GPT-4) model for five example patient profiles with diverse health conditions and fitness goals. Our focus was to assess the model's ability to generate exercise prescriptions based on a singular, initial interaction, akin to a typical user experience. The evaluation was conducted by leading experts in the field of exercise prescription. Five distinct scenarios were formulated, each representing a hypothetical individual with a specific health condition and fitness objective. Upon receiving details of each individual, the GPT-4 model was tasked with generating a 30-day exercise program. These AI-derived exercise programs were subsequently subjected to a thorough evaluation by experts in exercise prescription. The evaluation encompassed adherence to established principles of frequency, intensity, time, and exercise type; integration of perceived exertion levels; consideration for medication intake and the respective medical condition; and the extent of program individualization tailored to each hypothetical profile. The AI model could create general safety-conscious exercise programs for various scenarios. However, the AI-generated exercise prescriptions lacked precision in addressing individual health conditions and goals, often prioritizing excessive safety over the effectiveness of training. The AI-based approach aimed to ensure patient improvement through gradual increases in training load and intensity, but the model's potential to fine-tune its recommendations through ongoing interaction was not fully satisfying. AI technologies, in their current state, can serve as supplemental tools in exercise prescription, particularly in enhancing accessibility for individuals unable to access, often costly, professional advice. However, AI technologies are not yet recommended as a substitute for personalized, progressive, and health condition-specific prescriptions provided by healthcare and fitness professionals. Further research is needed to explore more interactive use of AI models and integration of real-time physiological feedback.

15.
Angew Chem Int Ed Engl ; 63(18): e202402259, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38421233

RESUMEN

Oligo(phenyleneethynylene)s (OPEs) have attracted widespread attention due to their remarkable (opto)electronic and photophysical properties, which have enabled numerous applications. The versatile functionalization possibilities of OPEs make them unique candidates to form various shape-persistent geometries, including linear, triangular, rectangular, hexagonal and macrocyclic. However, as a result of this structural variety, it is oftentimes challenging to correlate molecular design with self-assembly properties. In this minireview, we have classified OPEs based on their molecular shapes and correlated them with their self-assembly behavior in solution. Particularly, we provide important insights into the aggregation propensity of the different molecular shapes and how to tune the association strength using various non-covalent interactions. Our classification will enable a better understanding of the structure-property correlation in OPEs, which is key to develop supramolecular functional materials.

16.
Ann Surg Oncol ; 30(7): 4111-4119, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37012435

RESUMEN

BACKGROUND: For breast-conserving surgery (BCS), several alternatives to wire localization (WL) have been developed. The newest, electromagnetic seed localization (ESL), provides three-dimensional navigation using the electrosurgical tool. This study assessed operative times, specimen volumes, margin positivity, and re-excision rates for ESL and WL. METHODS: Patients who had ESL-guided breast-conserving surgery between August 2020 and August 2021 were reviewed and matched one-to-one with patients who had WL based on surgeon, procedure type, and pathology. Variables were compared between ESL and WL using Wilcoxon rank-sum and Fisher's exact tests. RESULTS: The study matched 97 patients who underwent excisional biopsy (n = 20) or partial mastectomy with (n = 53) or without (n = 24) sentinel lymph node biopsy (SLNB) using ESL. The median operative time for ESL versus WL for lumpectomy was 66 versus 69 min with SLNB (p = 0.76) and 40 versus 34.5 min without SLNB (p = 0.17). The median specimen volume was 36 cm3 using ESL versus 55 cm3 using WL (p = 0.001). For the patients with measurable tumor volume, excess tissue was greater using WL versus ESL (median, 73.2 vs. 52.5 cm3; p = 0.017). The margins were positive for 10 (10 %) of the 97 ESL patients and 18 (19 %) of the 97 WL patients (p = 0.17). In the ESL group, 6 (6 %) of the 97 patients had a subsequent re-excision compared with 13 (13 %) of the 97 WL patients (p = 0.15). CONCLUSIONS: Despite similar operative times, ESL is superior to WL, as evidenced by decreased specimen volume and excess tissue excised. Although the difference was not statistically significant, ESL resulted in fewer positive margins and re-excisions than WL. Further studies are needed to confirm that ESL is the most advantageous of the two methods.


Asunto(s)
Neoplasias de la Mama , Mastectomía Segmentaria , Humanos , Femenino , Mastectomía Segmentaria/métodos , Análisis por Apareamiento , Neoplasias de la Mama/cirugía , Mastectomía , Biopsia del Ganglio Linfático Centinela , Estudios Retrospectivos
17.
Chemistry ; 29(63): e202302254, 2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-37635073

RESUMEN

Self-assembling features, chiroptical activity, and spin filtering properties are reported for 2,15- and 4,13-disubstituted [6]helicenes decorated in their periphery with 3,4,5-tris(dodecyloxy)-N-(4-ethynylphenyl)benzamide moieties. The weak non-covalent interaction between these units conditions the corresponding circularly polarized luminescence and spin polarization. The self-assembly is overall weak for these [6]helicene derivatives that, despite the formation of H-bonding interactions between the amide groups present in the peripheral moieties, shows very similar chiroptical properties both in the monomeric or aggregated states. This effect could be explained by considering the steric effect that these groups could generate in the growing of the corresponding aggregate formed. Importantly, the self-assembling features also condition chiral induced spin selectivity (CISS effect), with experimental spin polarization (SP) values found between 35-40 % for both systems, as measured by magnetic-conducting atomic force microscopy (AFM) technique.

18.
Eur J Neurol ; 30(11): 3497-3506, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37329328

RESUMEN

BACKGROUND: Gut microbiota plays a role in the pathophysiology of ischaemic stroke (IS) through the bidirectional gut-brain axis. Nevertheless, little is known about sex-specific microbiota signatures in IS occurrence. METHODS: A total of 89 IS patients and 12 healthy controls were enrolled. We studied the taxonomic differences of the gut microbiota between men and women with IS by shotgun metagenomic sequencing. To evaluate the causal effect of several bacteria on IS risk, we performed a two-sample Mendelian randomisation (MR) with inverse-variance weighting (IVW) using genome-wide association analysis (GWAS) summary statistics from two cohorts of 5959 subjects with genetic and microbiota data and 1,296,908 subjects with genetic and IS data, respectively. RESULTS: α-Diversity analysis measured using Observed Species (p = 0.017), Chao1 (p = 0.009) and Abundance-based Coverage Estimator (p = 0.012) indexes revealed that IS men have a higher species richness compared with IS women. Moreover, we found sex-differences in IS patients in relation to the phylum Fusobacteria, class Fusobacteriia, order Fusobacteriales and family Fusobacteriaceae (all Bonferroni-corrected p < 0.001). MR confirmed that increased Fusobacteriaceae levels in the gut are causally associated with an increased risk of IS (IVW p = 0.02, ß = 0.32). CONCLUSIONS: Our study is the first to indicate that there are gut microbiome differences between men and women with IS, identifying high levels of Fusobacteriaceae in women as a specific risk factor for IS. Incorporating sex stratification analysis is important in the design, analysis and interpretation of studies on stroke and the gut microbiota.

19.
Microb Cell Fact ; 22(1): 119, 2023 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-37386435

RESUMEN

BACKGROUND: A processing methodology of raw starch extraction from avocado seeds (ASs) and a sequential hydrolysis and fermentation bioprocess in just a few steps was successfully obtained for the bioethanol production by a single yeast Saccharomyces cerevisiae strain and this research was also to investigate the optimum conditions for the pretreatment of biomass and technical procedures for the production of bioethanol. It successfully resulted in high yields and productivity of all the experiments from the laboratory scale and the pilot plant. Ethanol yields from pretreated starch are comparable with those in commercial industries that use molasses and hydrolyzed starch as raw materials. RESULTS: Before the pilot-scale bioethanol production, studies of starch extraction and dilute sulfuric acid-based pretreatment was carefully conducted. The amount of starch extracted from dry and fresh avocado seed was 16.85 g ± 0.34 g and 29.79 ± 3.18 g of dry starch, representing a yield of ∼17% and 30%, respectively. After a dilute sulfuric acid pretreatment of starch, the released reducing sugars (RRS) were obtained and the hydrolysate slurries containing glucose (109.79 ± 1.14 g/L), xylose (0.99 ± 0.06 g/L), and arabinose (0.38 ± 0.01 g/L). The efficiency of total sugar conversion was 73.40%, with a productivity of 9.26 g/L/h. The ethanol fermentation in a 125 mL flask fermenter showed that Saccharomyces cerevisiae (Fali, active dry yeast) produced the maximum ethanol concentration, pmax at 49.05 g/L (6.22% v/v) with a yield coefficient, Yp/s of 0.44 gEthanol/gGlucose, a productivity or production rate, rp at 2.01 g/L/h and an efficiency, Ef of 85.37%. The pilot scale experiments of the ethanol fermentation using the 40-L fermenter were also successfully achieved with essentially good results. The values of pmax,Yp/s, rp, and Ef of the 40-L scale were at 50.94 g/L (6.46% v/v), 0.45 gEthanol/gGlucose, 2.11 g/L/h, and 88.74%, respectively. Because of using raw starch, major by-products, i.e., acetic acid in the two scales were very low, in ranges of 0.88-2.45 g/L, and lactic acid was not produced, which are less than those values in the industries. CONCLUSIONS: The sequential hydrolysis and fermentation process of two scales for ethanol production using the combination of hydrolysis by utilizing dilute sulfuric acid-based pretreatment and fermentation by a single yeast Saccharomyces cerevisiae strain is practicable and feasible for realistic and effective scale-up strategies of bioethanol production from the starch of avocado seeds.


Asunto(s)
Persea , Saccharomyces cerevisiae , Almidón , Fermentación , Hidrólisis , Semillas , Etanol
20.
Conserv Biol ; 37(4): e14094, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37021395

RESUMEN

Evaluating the outcomes and tracking the trajectory of biodiversity offsets is essential to demonstrating their effectiveness as a mechanism to conciliate development and conservation. We reviewed the literature to determine the principles that should underpin biodiversity offset planning and the criteria for offset evaluation at the project level. According to the literature, the core principles of equivalence, additionality, and permanence are used as criteria to evaluate conservation outcomes of offsets. We applied the criteria to evaluate offsets of a large iron ore mining project in the Atlantic Forest in Brazil. We examined equivalence in terms of the amount of area per biodiversity value affected and fauna and flora similarity, additionality in terms of landscape connectivity, and permanence in terms of guarantees to ensure protection and restoration offsets lasting outcomes. We found an offset ratio (amount of affected area:offset area) of 1:1.8 for forests and 1:2 for grasslands. Ecological equivalence (i.e., similarity between affected and offset areas) was found for forested areas, but not for ferruginous rupestrian grasslands or for fauna. Landscape metrics showed that connectivity improved relative to the preproject situation as a result of locating restoration offsets in the largest and best-connected forest patch. Permanence of offsets was addressed by establishing covenants and management measures, but financial guarantees to cover maintenance costs after mine closure were lacking. Offsets should be equivalent in type and size, provide conservation outcomes that would not be obtained without them (additionality), and be lasting (permanence). To monitor and evaluate offsets, it is necessary to determine how well these 3 principles are applied in the planning, implementation, and maintenance of offsets. Achieving measurable conservation outcomes from offsets is a long-term endeavor that requires sustained management support, and is information intensive. Thus, offsets require ongoing monitoring and evaluation as well as adaptive management.


Evaluación del potencial de las compensaciones por biodiversidad para obtener ganancias netas Resumen La evaluación de resultados y el rastreo de la trayectoria de las compensaciones por biodiversidad son esenciales para demostrar su efectividad como mecanismo de conciliación entre el desarrollo y la conservación. Revisamos la literatura para determinar los principios que deberían sustentar los planes de compensación y los criterios para evaluarla a nivel de proyecto. Según la literatura, se usan los principios nucleares de equivalencia, adicionalidad y permanencia como criterio para evaluar los resultados de conservación de las compensaciones. Aplicamos este criterio para evaluar las compensaciones de un gran proyecto minero de mineral de hierro en el Bosque Atlántico de Brasil. Analizamos la equivalencia en términos de cantidad de área por valor de biodiversidad afectado y similitudes entre la flora y fauna; la adicionalidad en términos de conectividad de paisaje; y la permanencia en términos de las garantías que aseguran que las compensaciones tengan resultados longevos de restauración y protección. Descubrimos una proporción en las compensaciones (cantidad del área afectada:área de compensación) de 1:1.8 para los bosques y de 1:2 en los campos naturales. Encontramos equivalencias ecológicas (es decir, la similitud entre las áreas afectadas y las de compensación) para las áreas boscosas, pero no para los campos rupestres ferruginosos ni para la fauna. Las medidas del paisaje mostraron que la conectividad mejoró en relación a la situación previa al proyecto gracias a la ubicación de las compensaciones por restauración en los fragmentos de bosque más grandes y mejor conectados. Establecimos Contractos y medidas de manejo fueron establecidos la permanencia de las compensaciones, pero las garantías económicas para cubrir los costos de mantenimiento después del cierre de la mina no están suficientemente garantizadas. Las compensaciones deberían ser iguales en tipo y tamaño (equivalencia), proporcionar resultados de conservación que no se obtendrían en su ausencia (adicionalidad) y ser duraderas (permanencia). Se necesita determinar cómo se aplican estos tres principios en la planeación, implementación y mantenimiento de las compensaciones para poder monitorearlas. Si se quieren lograr resultados medibles de conservación, se necesita que el manejo cuente con un apoyo mantenido y a largo plazo que contenga con información intensiva. Por lo tanto, las compensaciones requieren un monitoreo y evaluación continua además del manejo adaptativo.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Bosques , Minería , Brasil , Ecosistema
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