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1.
J Colloid Interface Sci ; 675: 660-669, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38991280

RESUMO

The global rise in obesity necessitates innovative weight loss strategies. Naturally occurring smectite clays, such as montmorillonite (MMT), offer promise due to their unique properties that interfere with free fatty acid (FFA) liberation, reducing systemic uptake. However, the mechanisms of MMT-FFA interactions and their implications for weight management are undefined. This study investigates these interactions by adding MMT (10 % w/w) to in vitro lipolysis media containing medium chain triglycerides (MCTs), and monitoring FFA liberation using pH-stat titration. Nanoparticle tracking analysis (NTA) and synchrotron-based small-angle X-ray scattering (sSAXS) observed time-dependent structural changes, while electron microscopy examined clay morphology during digestion. A 35 % reduction in FFA liberation occurred after 25 min of digestion with MCT + MMT, with digestion kinetics following a biphasic model driven by calcium soap formation. NTA revealed a 17-fold decrease in vesicular structures with MCT + MMT, and sSAXS highlighted a rapid lamellar phase evolution linked to calcium soap formation. This acceleration is attributed to MMT's adsorption to unionized FFAs via hydrogen bonding, supported by TEM images showing a decrease in d-spacing, indicating FFA intercalation is not the main adsorption mechanism. These findings highlight MMT's potential as a novel intervention for reducing dietary lipid absorption in obesity and metabolic diseases.

2.
Theor Appl Genet ; 137(8): 179, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38980436

RESUMO

Rust diseases, including leaf rust, stripe/yellow rust, and stem rust, significantly impact wheat (Triticum aestivum L.) yields, causing substantial economic losses every year. Breeding and deployment of cultivars with genetic resistance is the most effective and sustainable approach to control these diseases. The genetic toolkit for wheat breeders to select for rust resistance has rapidly expanded with a multitude of genetic loci identified using the latest advances in genomics, mapping and cloning strategies. The goal of this review was to establish a wheat genome atlas that provides a comprehensive summary of reported loci associated with rust resistance. Our atlas provides a summary of mapped quantitative trait loci (QTL) and characterised genes for the three rusts from 170 publications over the past two decades. A total of 920 QTL or resistance genes were positioned across the 21 chromosomes of wheat based on the latest wheat reference genome (IWGSC RefSeq v2.1). Interestingly, 26 genomic regions contained multiple rust loci suggesting they could have pleiotropic effects on two or more rust diseases. We discuss a range of strategies to exploit this wealth of genetic information to efficiently utilise sources of resistance, including genomic information to stack desirable and multiple QTL to develop wheat cultivars with enhanced resistance to rust disease.


Assuntos
Basidiomycota , Mapeamento Cromossômico , Resistência à Doença , Doenças das Plantas , Locos de Características Quantitativas , Triticum , Triticum/genética , Triticum/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Resistência à Doença/genética , Basidiomycota/patogenicidade , Melhoramento Vegetal , Genoma de Planta , Genes de Plantas , Cromossomos de Plantas/genética
3.
Hum Brain Mapp ; 45(10): e26768, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38949537

RESUMO

Structural neuroimaging data have been used to compute an estimate of the biological age of the brain (brain-age) which has been associated with other biologically and behaviorally meaningful measures of brain development and aging. The ongoing research interest in brain-age has highlighted the need for robust and publicly available brain-age models pre-trained on data from large samples of healthy individuals. To address this need we have previously released a developmental brain-age model. Here we expand this work to develop, empirically validate, and disseminate a pre-trained brain-age model to cover most of the human lifespan. To achieve this, we selected the best-performing model after systematically examining the impact of seven site harmonization strategies, age range, and sample size on brain-age prediction in a discovery sample of brain morphometric measures from 35,683 healthy individuals (age range: 5-90 years; 53.59% female). The pre-trained models were tested for cross-dataset generalizability in an independent sample comprising 2101 healthy individuals (age range: 8-80 years; 55.35% female) and for longitudinal consistency in a further sample comprising 377 healthy individuals (age range: 9-25 years; 49.87% female). This empirical examination yielded the following findings: (1) the accuracy of age prediction from morphometry data was higher when no site harmonization was applied; (2) dividing the discovery sample into two age-bins (5-40 and 40-90 years) provided a better balance between model accuracy and explained age variance than other alternatives; (3) model accuracy for brain-age prediction plateaued at a sample size exceeding 1600 participants. These findings have been incorporated into CentileBrain (https://centilebrain.org/#/brainAGE2), an open-science, web-based platform for individualized neuroimaging metrics.


Assuntos
Envelhecimento , Encéfalo , Imageamento por Ressonância Magnética , Humanos , Adolescente , Feminino , Idoso , Adulto , Criança , Adulto Jovem , Masculino , Encéfalo/diagnóstico por imagem , Encéfalo/anatomia & histologia , Encéfalo/crescimento & desenvolvimento , Idoso de 80 Anos ou mais , Pré-Escolar , Pessoa de Meia-Idade , Envelhecimento/fisiologia , Imageamento por Ressonância Magnética/métodos , Neuroimagem/métodos , Neuroimagem/normas , Tamanho da Amostra
4.
J Women Aging ; : 1-16, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38976516

RESUMO

Aging Veterans face complex needs across multiple domains. However, the needs of older female Veterans and the degree to which unmet needs differ by sex are unknown. We analyzed responses to the HERO CARE survey from 7,955 Veterans aged 55 years and older (weighted N = 490,148), 93.9% males and 6.1% females. We evaluated needs and unmet needs across the following domains: activities of daily living (ADLs), instrumental ADLs (IADLs), health management, and social. We calculated weighted estimates and compared sex differences using age-adjusted prevalence ratios. On average, female Veterans were younger, more were Non-Hispanic Black and unmarried. Females and males reported a similar prevalence of problems across all domains. However, compared to males, female Veterans had a lesser prevalence of missed appointments due to transportation (aPR 0.49; 95% CI: 0.26-0.92), housework unmet needs (aPR: 0.44; 95% CI: 0.20-0.97), and medication management unmet needs (aPR: 0.33; 95% CI: 0.11-0.95) but a higher prevalence of healthcare communication unmet needs (aPR: 2.40; 95% CI: 1.13-5.05) and monitoring health conditions unmet needs (aPR: 2.13, 95% CI: 1.08-4.20). Female Veterans' common experience of unmet needs in communicating with their healthcare teams could result in care that is less aligned with their preferences or needs. As the number of older female Veterans grows, these data and additional work to understand sex-specific unmet needs and ways to address them are essential to providing high-quality care for female Veterans.

5.
Lancet Infect Dis ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38971177

RESUMO

The diagnosis of paediatric tuberculosis remains a challenge due to the non-specificity of symptoms and the paucibacillary nature of tuberculosis in children. However, in the development of new tuberculosis diagnostics, the unique needs of children and adolescents are rarely considered in the design process, with delays in evaluation and approval. No clear guidance is available on when and how to include children and adolescents in tuberculosis diagnostic development and evaluation. To address this gap, we conducted a Delphi consensus process with 42 stakeholders, including one qualitative and two quantitative rounds. Consensus was achieved on 20 statements, with agreement that the needs and perspectives of children, adolescents, and their caregivers should be incorporated throughout diagnostic design and evaluation. Opportunities exist for the early use of well characterised samples and prospective enrolment of children and adolescents in tuberculosis diagnostic evaluation, with consideration of the type of test, expected benefit, and potential risks. Pathogen-based tests might be initially optimised and assessed in adults and adolescents, but parallel evaluation in children is needed for host-based tests. Late-stage evaluation and implementation studies should examine combination testing and integration into clinical algorithms. The statements support collaboration between developers, researchers, regulators, and users to widen and accelerate the diagnostic pipeline for paediatric tuberculosis.

6.
ISME J ; 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39001714

RESUMO

In recent years, phylogenetic reconciliation has emerged as a promising approach for studying microbial ecology and evolution. The core idea is to model how gene trees evolve along a species tree, and to explain differences between them via evolutionary events including gene duplications, transfers, and losses. Here, we describe how phylogenetic reconciliation provides a natural framework for studying genome evolution, and highlight recent applications including ancestral gene content inference, the rooting of species trees, and the insights into metabolic evolution and ecological transitions they yield. Reconciliation analyses have elucidated the evolution of diverse microbial lineages, from Chlamydiae to Asgard archaea, shedding light on ecological adaptation, host-microbe interactions, and symbiotic relationships. However, there are many opportunities for broader application of the approach in microbiology. Continuing improvements to make reconciliation models more realistic and scalable, and integration of ecological metadata such as habitat, pH, temperature and oxygen use, offer enormous potential for understanding the rich tapestry of microbial life.

7.
Artigo em Inglês | MEDLINE | ID: mdl-39001763

RESUMO

BACKGROUND: Dark-blood late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) has better correlation with bipolar voltage (BiV) to define ablation scar in the left atrium (LA) compared to conventional bright-blood LGE CMR. OBJECTIVES: This study sought to determine the optimal signal intensity threshold of dark-blood LGE CMR to identify LA ablation scar. METHODS: In 54 patients scheduled for atrial fibrillation ablation, image intensity ratios (IIRs) were derived from preprocedural dark-blood LGE CMR. In 26 patients without previous ablation, the upper limit of normal was derived from the 95th and 98th percentiles of pooled IIR values. In 28 patients with previous atrial fibrillation ablation, BiV was compared with the corresponding IIR. Receiver-operating characteristics analyses were employed to determine the optimal IIR threshold (ie, the point with the smallest distance to the upper left corner of the receiver-operating characteristics) for LA ablation scar (BiV ≤0.15 mV). RESULTS: Upper limit of normal corresponded to IIR values 1.16 and 1.21, yielding low sensitivities of 0.32 and 0.09 to detect LA ablation scar. Receiver-operating characteristics analysis of IIR and BiV comparison achieved a median area under the curve of 0.77. Median optimal IIR threshold for LA ablation scar was 1.09, with an average sensitivity of 0.73, specificity of 0.75, and accuracy of 0.71. Median IIR thresholds of 1.00 and 1.10 corresponded to 80% sensitivity and 80% specificity, respectively. There was considerable interpatient variability: optimal IIR thresholds per patient ranged from 1.01 to 1.22. CONCLUSIONS: The optimal IIR threshold to identify LA ablation scar by dark-blood LGE CMR is 1.09. Because of interpatient variability, the investigators recommend using a lower (1.00) and upper (1.10) threshold to prevent over- or underestimation of ablation scar.

8.
Exp Mol Med ; 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38825648

RESUMO

Non-small cell lung carcinoma (NSCLC) exhibits a heightened propensity for brain metastasis, posing a significant clinical challenge. Mucin 5ac (MUC5AC) plays a pivotal role in the development of lung adenocarcinoma (LUAD); however, its role in causing brain metastases remains unknown. In this study, we aimed to investigate the contribution of MUC5AC to brain metastasis in patients with LUAD utilizing various brain metastasis models. Our findings revealed a substantial increase in the MUC5AC level in LUAD brain metastases (LUAD-BrM) samples and brain-tropic cell lines compared to primary samples or parental control cell lines. Intriguingly, depletion of MUC5AC in brain-tropic cells led to significant reductions in intracranial metastasis and tumor growth, and improved survival following intracardiac injection, in contrast to the observations in the control groups. Proteomic analysis revealed that mechanistically, MUC5AC depletion resulted in decreased expression of metastasis-associated molecules. There were increases in epithelial-to-mesenchymal transition, tumor invasiveness, and metastasis phenotypes in tumors with high MUC5AC expression. Furthermore, immunoprecipitation and proteomic analysis revealed a novel interaction of MUC5AC with Annexin A2 (ANXA2), which activated downstream matrix metalloproteases and facilitated extracellular matrix degradation to promote metastasis. Disrupting MUC5AC-ANXA2 signaling with a peptide inhibitor effectively abrogated the metastatic process. Additionally, treatment of tumor cells with an astrocyte-conditioned medium or the chemokine CCL2 resulted in upregulation of MUC5AC expression and enhanced brain colonization. In summary, our study demonstrates that the MUC5AC/ANXA2 signaling axis promotes brain metastasis, suggesting a potential therapeutic paradigm for LUAD patients with high MUC5AC expression.

9.
Nat Commun ; 15(1): 5414, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926353

RESUMO

Borgs are huge extrachromosomal elements (ECE) of anaerobic methane-consuming "Candidatus Methanoperedens" archaea. Here, we used nanopore sequencing to validate published complete genomes curated from short reads and to reconstruct new genomes. 13 complete and four near-complete linear genomes share 40 genes that define a largely syntenous genome backbone. We use these conserved genes to identify new Borgs from peatland soil and to delineate Borg phylogeny, revealing two major clades. Remarkably, Borg genes encoding nanowire-like electron-transferring cytochromes and cell surface proteins are more highly expressed than those of host Methanoperedens, indicating that Borgs augment the Methanoperedens activity in situ. We reconstructed the first complete 4.00 Mbp genome for a Methanoperedens that is inferred to be a Borg host and predicted its methylation motifs, which differ from pervasive TC and CC methylation motifs of the Borgs. Thus, methylation may enable Methanoperedens to distinguish their genomes from those of Borgs. Very high Borg to Methanoperedens ratios and structural predictions suggest that Borgs may be capable of encapsulation. The findings clearly define Borgs as a distinct class of ECE with shared genomic signatures, establish their diversification from a common ancestor with genetic inheritance, and raise the possibility of periodic existence outside of host cells.


Assuntos
Genoma Arqueal , Metano , Filogenia , Metano/metabolismo , Oxirredução , Archaea/genética , Archaea/metabolismo , Sequenciamento por Nanoporos/métodos , Metilação de DNA , Microbiologia do Solo
10.
Phys Imaging Radiat Oncol ; 30: 100590, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38827886

RESUMO

Background and purpose: For locally advanced non-small cell lung cancer (LA-NSCLC), intensity-modulated proton therapy (IMPT) can reduce organ at risk (OAR) doses compared to intensity-modulated radiotherapy (IMRT). Deep inspiration breath hold (DIBH) reduces OAR doses compared to free breathing (FB) in IMRT. In IMPT, differences in dose distributions and robustness between DIBH and FB are unclear. In this study, we compare DIBH to FB in IMPT, and IMPT to IMRT. Materials and methods: Fortyone LA-NSCLC patients were prospectively included. 4D computed tomography images (4DCTs) and DIBH CTs were acquired for treatment planning and during weeks 1 and 3 of treatment. A new system for automated robust planning was developed and used to generate a FB and a DIBH IMPT plan for each patient. Plans were compared in terms of dose-volume parameters and normal tissue complication probabilities (NTCPs). Dose recalculations on repeat CTs were used to compare inter-fraction plan robustness. Results: In IMPT, DIBH reduced median lungs Dmean from 9.3 Gy(RBE) to 8.0 Gy(RBE) compared to FB, and radiation pneumonitis NTCP from 10.9 % to 9.4 % (p < 0.001). Inter-fraction plan robustness for DIBH and FB was similar. Median NTCPs for radiation pneumonitis and mortality were around 9 percentage points lower with IMPT than IMRT (p < 0.001). These differences were much larger than between FB and DIBH within each modality. Conclusion: DIBH IMPT resulted in reduced lung dose and radiation pneumonitis NTCP compared to FB IMPT. Inter-fraction robustness was comparable. OAR doses were far lower in IMPT than IMRT.

12.
Lancet Reg Health West Pac ; 46: 101047, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38827931

RESUMO

Tuberculosis (TB) is the leading infectious cause of morbidity and mortality globally. Despite available tools for preventing, finding, and treating TB, many people with TB remain undiagnosed. In high-incidence settings, TB transmission is ubiquitous within the community, affecting both high-risk groups and the general population. In fact, most people who develop TB come from the general population. To disrupt the chain of transmission that sustains the TB epidemic, we need to find and treat everyone with infectious TB as early as possible, including those with minimal symptoms or subclinical TB who are unlikely to present for care. Important elements of an effective active case-finding strategy include effective social mobilisation and community engagement, using sensitive screening tools that can be used at scale, and embracing population-wide screening in high-incidence ('hot spot') areas. We require a better description of feasible delivery models, 'real-life' impact and cost effectiveness to enable wider implementation.

13.
G3 (Bethesda) ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38869232

RESUMO

Maintaining genetic diversity in cultured shellfish can be challenging due to high variance in individual reproductive success, founder effects, and rapid genetic drift, but is important to retain adaptive potential and avoid inbreeding depression. To support broodstock management and selective breeding in cultured Pacific oysters (Crassostrea (Magallana) gigas), we developed an amplicon panel targeting 592 genomic regions and SNP variants with an average of 50 amplicons per chromosome. Target SNPs were selected based on elevated observed heterozygosity or differentiation in Pacific oyster populations in British Columbia, Canada. The use of the panel for parentage applications was evaluated using multiple generations of oysters from a breeding program on Vancouver Island, Canada (n = 181) and families selected for Ostreid herpesvirus-1 resistance from the Molluscan Broodstock Program in Oregon, USA (n = 136). Population characterization was evaluated using wild, naturalized, farmed, or hatchery oysters sampled throughout the Northern Hemisphere (n = 190). Technical replicates showed high genotype concordance (97.5%; n = 68 replicates). Parentage analysis found suspected pedigree and sample handling errors, demonstrating the panel's value for quality control in breeding programs. Suspected null alleles were identified and found to be largely population dependent, suggesting population-specific variation impacting target amplification. Null alleles were identified using existing data without the need for pedigree information, and once they were removed, assignment rates increased to 93.0% and 86.0% of possible assignments in the two breeding program datasets. A pipeline for analyzing the amplicon sequence data from sequencer output, amplitools, is also provided.

14.
Lancet Glob Health ; 12(7): e1184-e1191, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38876764

RESUMO

Better access to tuberculosis testing is a key priority for fighting tuberculosis, the leading cause of infectious disease deaths in people. Despite the roll-out of molecular WHO-recommended rapid diagnostics to replace sputum smear microscopy over the past decade, a large diagnostic gap remains. Of the estimated 10·6 million people who developed tuberculosis globally in 2022, more than 3·1 million were not diagnosed. An exclusive focus on improving tuberculosis test accuracy alone will not be sufficient to close the diagnostic gap for tuberculosis. Diagnostic yield, which we define as the proportion of people in whom a diagnostic test identifies tuberculosis among all people we attempt to test for tuberculosis, is an important metric not adequately explored. Diagnostic yield is particularly relevant for subpopulations unable to produce sputum such as young children, people living with HIV, and people with subclinical tuberculosis. As more accessible non-sputum specimens (eg, urine, oral swabs, saliva, capillary blood, and breath) are being explored for point-of-care tuberculosis testing, the concept of yield will be of growing importance. Using the example of urine lipoarabinomannan testing, we illustrate how even tests with limited sensitivity can diagnose more people with tuberculosis if they enable increased diagnostic yield. Using tongue swab-based molecular tuberculosis testing as another example, we provide definitions and guidance for the design and conduct of pragmatic studies that assess diagnostic yield. Lastly, we show how diagnostic yield and other important test characteristics, such as cost and implementation feasibility, are essential for increased effective population coverage, which is required for optimal clinical care and transmission impact. We are calling for diagnostic yield to be incorporated into tuberculosis test evaluation processes, including the WHO Grading of Recommendations, Assessment, Development, and Evaluations process, providing a crucial real-life implementation metric that complements traditional accuracy measures.


Assuntos
Tuberculose , Humanos , Testes Diagnósticos de Rotina , Escarro/microbiologia , Tuberculose/diagnóstico
15.
Ticks Tick Borne Dis ; 15(6): 102361, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38880004

RESUMO

The genus Amblyomma contains the highest percentage of reptile-associated ticks, and comprises approximately nine subgenera. One of these subgenera is Adenopleura, which also encompasses Amblyomma javanense, and its type species Amblyomma compressum. This study describes a new Amblyomma species associated with Bengal monitor lizards (Varanus bengalensis) based on morphology and its mitogenome in Khyber Pakhtunkhwa, Pakistan. Reptiles belonging to different genera were examined for Amblyomma ticks and only the monitor lizard was infested with ticks in the District Bajaur. Collected Amblyomma cf. javanense ticks were analyzed and formally described as a new species. Overall, 57 A. cf. javanense ticks were collected on monitor lizards (4/27) with a 15% prevalence of infestation, 2.1 mean abundance, and 14.3 mean intensity. Ticks comprised males (n = 23, 40%), females (n = 14, 25%) and nymphs (n = 20, 35%), while no larvae were found. BLAST analysis of A. cf. javanense sequences showed the following maximum identities; 98.25% with undetermined Amblyomma species based on 12S rRNA, 96.07% with A. javanense based on 16S rRNA, 99.56% and 90.95% with an Amblyomma sp. and A. javanense, respectively, based on ITS2. Moreover, the mitochondrial genome of A. cf. javanense showed maximum identities of 80.75%, 80.48% and 79.42% with Amblyomma testudinarium, A. javanense, and Amblyomma sp., respectively. The phylogenetic analysis of A. cf. javanense revealed that its 12S rRNA and 16S rRNA are closely related to an Amblyomma sp. and A. javanense, respectively, from Sri Lanka, its ITS2 is closely related to A. javanense from China and an Amblyomma sp. from Sri Lanka, and its mitogenome is closely related to A. javanense and Amblyomma sp. from China. The pairwise distance analysis resulted in divergence of 0-1.71% (12S rRNA), 0-17.5% (16S rRNA), 0-9.1% (ITS2) and 0-20.5% (mitochondrial genome). We also contributed the full-length mitochondrial genome sequence of A. compressum and showed that this species does not share a most recent common ancestor with A. javanense. As the subgenus Adenopleura is paraphyletic, this study could help to understand the systematics and phylogeny of this taxon.

16.
Artigo em Inglês | MEDLINE | ID: mdl-38834231

RESUMO

BACKGROUND: There is evidence that the transition to retirement can bring social challenges and may increase loneliness. Few studies have examined the impact of retirement on loneliness; most have been conducted in Western countries. It is important to examine the differences in loneliness postretirement across countries to identify patterns and risk factors that might influence the health and well-being of older adults. We aimed to examine the effect of retirement on loneliness among older adults in Australia, China and the USA. METHODS: Longitudinal analysis of data from population-based samples of Australian, Chinese and American adults over 50. Lagged and fully lagged adjusted models were applied. Social engagement was examined as an effect modifier and a sensitivity analysis was conducted among urban participants. RESULTS: Retirees had a higher predicted prevalence of loneliness than non-retirees in Australia (19.4% (95% CI 18.0% to 20.9%) vs 17.0% (95% CI 15.7% to 18.4%)) and in the USA (19.3% (95% CI 17.5% to 21.1%) vs 15.7% (95% CI 14.3% to 17.3%)). These differences were significant only in the USA. In China, loneliness was significantly lower in those who had retired (10.0% (95% CI 7.9% to 12.5%) vs 17.1% (95% CI 15.7% to 18.5%)). In Australia and the USA, voluntary retirees had the lowest loneliness and involuntary retirees had the highest. Social engagement did not modify the association between retirement and loneliness. CONCLUSIONS: Our findings imply that the effect of retirement should be considered within a cultural context to inform suitable and effective strategies to alleviate loneliness.

17.
J Colloid Interface Sci ; 672: 256-265, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38838633

RESUMO

HYPOTHESIS: Understanding the digestion of lipid-based pharmaceutical formulations and food systems is necessary for optimising drug and nutrient delivery and has been extensively studied in bulk emulsion systems using the pH-stat method [1]. However, this approach is not suitable for investigation of individual lipid droplets, in particular the interface where the lipase acts. Microfluidic approaches to study digestion at lipid-water interfaces using droplet trapping have been proposed, however the aqueous phase in that case washes over the interface presenting uncertainty over the stoichiometry of interactions [2]. The internal interface of a Janus-like droplet, containing distinct aqueous and lipid compartments, mimics the interface of a lipid droplet in aqueous solution with controlled stoichiometry [3]. Hence, it was hypothesised that the internal interface of Janus droplets can offer a precise way to study the enzymatic digestion of lipids formulations. EXPERIMENTS: Using microfluidic methods, Janus-like droplets were formed by coalescing emulsion droplets containing lipid formulation and pancreatic lipase. Polarised light microscopy (PLM) and in-situ small-angle X-ray scattering (SAXS) were used to investigate the droplets. FINDINGS: PLM revealed the growth of an aligned inverse hexagonal phase (H2), and with SAXS showed that this phase transformation and alignment resulted from enzymatic digestion. A subsequent partial transformation from H2 to inverse bicontinuous cubic phase occurred when simulated intestinal fluid was used instead of Tris buffer. Suggesting that phospholipids and bile salts could diffuse across the internal interface to locally affect their surroundings.


Assuntos
Lipase , Lipase/química , Lipase/metabolismo , Transição de Fase , Emulsões/química , Tamanho da Partícula , Espalhamento a Baixo Ângulo , Gotículas Lipídicas/química , Gotículas Lipídicas/metabolismo , Lipídeos/química , Difração de Raios X , Propriedades de Superfície
18.
ACS Nano ; 18(26): 16766-16775, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38881465

RESUMO

Chirality is omnipresent in the living world. As biomimetic nanotechnology and self-assembly advance, they too need chirality. Accordingly, there is a pressing need to develop general methods to characterize chiral building blocks at the nanoscale in liquids such as water─the medium of life. Here, we demonstrate the chiroptical second-harmonic Tyndall scattering effect. The effect was observed in Si nanohelices, an example of a high-refractive-index dielectric nanomaterial. For three wavelengths of illumination, we observe a clear difference in the second-harmonic scattered light that depends on the chirality of the nanohelices and the handedness of circularly polarized light. Importantly, we provide a theoretical analysis that explains the origin of the effect and its direction dependence, resulting from different specific contributions of "electric dipole-magnetic dipole" and "electric dipole-electric quadrupole" coupling tensors. Using numerical simulations, we narrow down the number of such terms to 8 in forward scattering and to a single one in right-angled scattering. For chiral scatterers such as high-refractive-index dielectric nanoparticles, our findings expand the Tyndall scattering regime to nonlinear optics. Moreover, our theory can be broadened and adapted to further classes where such scattering has already been observed or is yet to be observed.

19.
Anim Genet ; 55(4): 540-558, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38885945

RESUMO

Unfavorable genetic correlations between milk production, fertility, and urea traits have been reported. However, knowledge of the genomic regions associated with these unfavorable correlations is limited. Here, we used the correlation scan method to identify and investigate the regions driving or antagonizing the genetic correlations between production vs. fertility, urea vs. fertility, and urea vs. production traits. Driving regions produce an estimate of correlation that is in the same direction as the global correlation. Antagonizing regions produce an estimate in the opposite direction of the global estimates. Our dataset comprised 6567, 4700, and 12,658 Holstein cattle with records of production traits (milk yield, fat yield, and protein yield), fertility (calving interval) and urea traits (milk urea nitrogen and blood urea nitrogen predicted using milk-mid-infrared spectroscopy), respectively. Several regions across the genome drive the correlations between production, fertility, and urea traits. Antagonizing regions were confined to certain parts of the genome and the genes within these regions were mostly involved in preventing metabolic dysregulation, liver reprogramming, metabolism remodeling, and lipid homeostasis. The driving regions were enriched for QTL related to puberty, milk, and health-related traits. Antagonizing regions were mostly related to muscle development, metabolic body weight, and milk traits. In conclusion, we have identified genomic regions of potential importance for dairy cattle breeding. Future studies could investigate the antagonizing regions as potential genomic regions to break the unfavorable correlations and improve milk production as well as fertility and urea traits.


Assuntos
Fertilidade , Leite , Locos de Características Quantitativas , Ureia , Animais , Bovinos/genética , Fertilidade/genética , Ureia/metabolismo , Leite/química , Leite/metabolismo , Feminino , Lactação/genética , Austrália , Fenótipo , Cruzamento
20.
Front Microbiol ; 15: 1374458, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38827153

RESUMO

Background: Tuberculous meningitis (TBM) is the most severe form of tuberculosis (TB) and can be difficult to diagnose and treat. We aimed to describe the clinical presentation, diagnosis, disease spectrum, outcome, and prognostic factors of patients treated for TBM in China. Methods: A multicenter retrospective study was conducted from 2009 to 2019 enrolling all presumptive TBM patients referred to Xijing tertiary Hospital from 27 referral centers in and around Shaanxi province, China. Patients with clinical features suggestive of TBM (abnormal CSF parameters) were included in the study if they had adequate baseline information to be classified as "confirmed," "probable," or "possible" TBM according to international consensus TBM criteria and remained in follow-up. Patients with a confirmed alternative diagnosis or severe immune compromise were excluded. Clinical presentation, central nervous system imaging, cerebrospinal fluid (CSF) results, TBM score, and outcome-assessed using the modified Barthel disability index-were recorded and compared. Findings: A total of 341 presumptive TBM patients met selection criteria; 63 confirmed TBM (25 culture positive, 42 Xpert-MTB/RIF positive), 66 probable TBM, 163 possible TBM, and 49 "not TBM." Death was associated with BMRC grade III (OR = 5.172; 95%CI: 2.298-11.641), TBM score ≥ 15 (OR = 3.843; 95%CI: 1.372-10.761), age > 60 years (OR = 3.566; 95%CI: 1.022-12.442), and CSF neutrophil ratio ≥ 25% (OR = 2.298; 95%CI: 1.027-5.139). Among those with confirmed TBM, nearly one-third (17/63, 27.0%) had a TBM score < 12; these patients exhibited less classic meningitis symptoms and signs and had better outcomes compared with those with a TBM score ≥ 12. In this group, signs of disseminated/miliary TB (OR = 12.427; 95%CI: 1.138-135.758) and a higher TBM score (≥15, OR = 8.437; 95%CI: 1.328-53.585) were most strongly associated with death. Conclusion: TBM patients who are older (>60 years) have higher TBM scores or CSF neutrophil ratios, have signs of disseminated/miliary TB, and are at greatest risk of death. In general, more effort needs to be done to improve early diagnosis and treatment outcome in TBM patients.

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