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1.
New Phytol ; 242(4): 1630-1644, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38105548

RESUMO

Nonmycorrhizal cluster root-forming species enhance the phosphorus (P) acquisition of mycorrhizal neighbours in P-impoverished megadiverse systems. However, whether mycorrhizal plants facilitate the defence of nonmycorrhizal plants against soil-borne pathogens, in return and via their symbiosis, remains unknown. We characterised growth and defence-related compounds in Banksia menziesii (nonmycorrhizal) and Eucalyptus todtiana (ectomycorrhizal, ECM) seedlings grown either in monoculture or mixture in a multifactorial glasshouse experiment involving ECM fungi and native oomycete pathogens. Roots of B. menziesii had higher levels of phytohormones (salicylic and jasmonic acids, jasmonoyl-isoleucine and 12-oxo-phytodienoic acid) than E. todtiana which further activated a salicylic acid-mediated defence response in roots of B. menziesii, but only in the presence of ECM fungi. We also found that B. menziesii induced a shift in the defence strategy of E. todtiana, from defence-related secondary metabolites (phenolic and flavonoid) towards induced phytohormone response pathways. We conclude that ECM fungi play a vital role in the interactions between mycorrhizal and nonmycorrhizal plants in a severely P-impoverished environment, by introducing a competitive component within the facilitation interaction between the two plant species with contrasting nutrient-acquisition strategies. This study sheds light on the interplay between beneficial and detrimental soil microbes that shape plant-plant interaction in severely nutrient-impoverished ecosystems.


Assuntos
Micorrizas , Oomicetos , Fósforo , Micorrizas/fisiologia , Fósforo/metabolismo , Oomicetos/fisiologia , Oomicetos/patogenicidade , Eucalyptus/microbiologia , Eucalyptus/fisiologia , Raízes de Plantas/microbiologia , Raízes de Plantas/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Plântula/microbiologia , Simbiose/fisiologia , Especificidade da Espécie , Meio Ambiente
2.
New Phytol ; 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39101264

RESUMO

In severely phosphorus (P)-impoverished environments, plants have evolved to use P very efficiently. Yet, it is unclear how P allocation in leaves contributes to their photosynthetic P-use efficiency (PPUE) and position along the leaf economics spectrum (LES). We address this question in 10 species of Banksia and Hakea, two highly P-efficient Proteaceae genera. We characterised traits in leaves of Banksia and Hakea associated with the LES: leaf mass per area, light-saturated photosynthetic rates, P and nitrogen concentrations, and PPUE. We also determined leaf P partitioning to five biochemical fractions (lipid, nucleic acid, metabolite, inorganic and residual P) and their possible association with the LES. For both genera, PPUE was negatively correlated with fractional allocation of P to lipids, but positively correlated with that to metabolites. For Banksia only, PPUE was negatively correlated with residual P, highlighting a strategy contrasting to that of Hakea. Phosphorus-allocation patterns significantly explained PPUE but were not linked to the resource acquisition vs resource conservation gradient defined by the LES. We conclude that distinct P-allocation patterns enable species from different genera to achieve high PPUE and discuss the implications of different P investments. We surmise that different LES axes representing different ecological strategies coexist in extremely P-impoverished environments.

3.
Phys Rev Lett ; 131(26): 262501, 2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38215380

RESUMO

The excited states of unstable ^{20}O were investigated via γ-ray spectroscopy following the ^{19}O(d,p)^{20}O reaction at 8 AMeV. By exploiting the Doppler shift attenuation method, the lifetimes of the 2_{2}^{+} and 3_{1}^{+} states were firmly established. From the γ-ray branching and E2/M1 mixing ratios for transitions deexciting the 2_{2}^{+} and 3_{1}^{+} states, the B(E2) and B(M1) were determined. Various chiral effective field theory Hamiltonians, describing the nuclear properties beyond ground states, along with a standard USDB interaction, were compared with the experimentally obtained data. Such a comparison for a large set of γ-ray transition probabilities with the valence space in medium similarity renormalization group ab initio calculations was performed for the first time in a nucleus far from stability. It was shown that the ab initio approaches using chiral effective field theory forces are challenged by detailed high-precision spectroscopic properties of nuclei. The reduced transition probabilities were found to be a very constraining test of the performance of the ab initio models.

4.
Am J Surg ; 231: 96-99, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38423807

RESUMO

INTRODUCTION: Reconstructive ileal-pouch anal anastomosis (IPAA) for ulcerative colitis (UC) is often created in 3-stages: colectomy â€‹+ â€‹ileostomy, proctectomy â€‹+ â€‹pouch creation with diverting loop ileostomy, then subsequent ileostomy closure. Modified 2-stage IPAA is without pouch diversion, thus avoiding a third operation. This study compares perioperative complications, quality of life (QOL) and functional outcomes of 3- versus modified 2-stage IPAA. METHODS: Charts were reviewed for adult UC patients undergoing IPAA between 2010 and 2020. QOL and function were assessed with EQ-5D-3L Quality of Life and Pouch Functional Score questionnaires. RESULTS: 152 patients were identified. 43 modified 2-stage and 109 3-stage IPAA were similar for anastomotic leak (9.3% vs. 1.8%, p â€‹= â€‹0.06), SSI (34.9% vs. 29.7%, p â€‹= â€‹0.51) and ileus (32.6% vs. 33%, p â€‹= â€‹0.96). Modified 2-stage had less bowel obstruction than 3-stage IPAA (7.0% vs. 30.1%, p â€‹= â€‹0.006). 92 patients returned questionnaires with similar QOL and pouch function. CONCLUSIONS: Perioperative complications, QOL and function are similar for 3-stage IPAA and modified 2-stage IPAA. Modified 2-stage IPAA in select patients is safe and has less postoperative bowel obstruction than 3-stage IPAA.


Assuntos
Colite Ulcerativa , Bolsas Cólicas , Proctocolectomia Restauradora , Adulto , Humanos , Qualidade de Vida , Resultado do Tratamento , Proctocolectomia Restauradora/efeitos adversos , Colite Ulcerativa/cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/cirurgia , Anastomose Cirúrgica , Estudos Retrospectivos
5.
iScience ; 27(4): 109364, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38523779

RESUMO

Visual responses of the primary visual cortex (V1) are altered by sound. Sound-driven behavioral arousal suggests that, in addition to direct inputs from the primary auditory cortex (A1), multiple other sources may shape V1 responses to sound. Here, we show in anesthetized mice that sound (white noise, ≥70dB) drives a biphasic modulation of V1 visually driven gamma-band activity, comprising fast-transient inhibitory and slow, prolonged excitatory (A1-independent) arousal-driven components. An analogous yet quicker modulation of the visual response also occurred earlier in the visual pathway, at the level of the dorsolateral geniculate nucleus (dLGN), where sound transiently inhibited the early phasic visual response and subsequently induced a prolonged increase in tonic spiking activity and gamma rhythmicity. Our results demonstrate that sound-driven modulations of visual activity are not exclusive to V1 and suggest that thalamocortical inputs from the dLGN to V1 contribute to shaping V1 visual response to sound.

6.
Clin Rheumatol ; 43(3): 895-905, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38340224

RESUMO

Autoimmune thyroid disease (AITD) is the most prevalent autoimmune disease. It shares multiple genetic, clinical, and serologic characteristics with rheumatoid arthritis (RA). Although frequently described as a classic form of single-organ autoimmunity, the AITD disease burden in a subset of patients extends well beyond the thyroid gland. This review explores the complex interaction between the two diseases and the clinical consequences when they overlap. Beyond the well-known effects of AITD on thyroid function in RA, there is mounting evidence of the association of both conditions impacting the presentation and outcomes of diabetes, metabolic syndrome, and cardiovascular disease. An increasing number of studies suggest that there are negative effects of AITD on RA disease activity both in the presence and in the absence of thyroid dysfunction. Recent evidence suggests that AITD may not only worsen the cumulative damage of RA through higher disease activity but may also worsen secondary osteoarthritis changes. Less well-known is the significant association between AITD and chronic widespread pain syndromes including fibromyalgia. Importantly, the presence of fibromyalgia, which is increased in RA patients, appears to be further increased when it overlaps with AITD. Lastly, we probe the possible influence of AITD interacting with RA on fertility and clinical depression. Key Points • Autoimmune thyroid disease is the most common autoimmune disease and is frequently associated with rheumatoid arthritis. • Autoimmune thyroid disease can present with osteoarthritis, inflammatory arthritis, and chronic widespread pain syndromes. • The co-occurrence of autoimmune thyroid disease and rheumatoid arthritis may worsen disease activity and exacerbate other disease manifestations including cardiovascular disease, fertility, and depression. • The overlap of rheumatoid arthritis with autoimmune thyroid disease needs further research and should be sought in general clinical practice.


Assuntos
Artrite Reumatoide , Doenças Autoimunes , Doenças Cardiovasculares , Fibromialgia , Doença de Hashimoto , Osteoartrite , Doenças da Glândula Tireoide , Humanos , Fibromialgia/complicações , Doenças Cardiovasculares/complicações , Artrite Reumatoide/complicações , Doença de Hashimoto/complicações , Doenças da Glândula Tireoide/complicações , Osteoartrite/complicações , Dor/complicações , Doenças Autoimunes/complicações , Doenças Autoimunes/epidemiologia
7.
J Control Release ; 368: 566-579, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38438093

RESUMO

Intravenous (IV) iron-carbohydrate complexes are widely used nanoparticles (NPs) to treat iron deficiency anaemia, often associated with medical conditions such as chronic kidney disease, heart failure and various inflammatory conditions. Even though a plethora of physicochemical characterisation data and clinical studies are available for these products, evidence-based correlation between physicochemical properties of iron-carbohydrate complexes and clinical outcome has not fully been elucidated yet. Studies on other metal oxide NPs suggest that early interactions between NPs and blood upon IV injection are key to understanding how differences in physicochemical characteristics of iron-carbohydrate complexes cause variance in clinical outcomes. We therefore investigated the core-ligand structure of two clinically relevant iron-carbohydrate complexes, iron sucrose (IS) and ferric carboxymaltose (FCM), and their interactions with two structurally different human plasma proteins, human serum albumin (HSA) and fibrinogen, using a combination of cryo-scanning transmission electron microscopy (cryo-STEM), x-ray diffraction (XRD), small-angle x-ray scattering (SAXS) and small-angle neutron scattering (SANS). Using this orthogonal approach, we defined the nano-structure, individual building blocks and surface morphology for IS and FCM. Importantly, we revealed significant differences in the surface morphology of the iron-carbohydrate complexes. FCM shows a localised carbohydrate shell around its core, in contrast to IS, which is characterised by a diffuse and dynamic layer of carbohydrate ligand surrounding its core. We hypothesised that such differences in carbohydrate morphology determine the interaction between iron-carbohydrate complexes and proteins and therefore investigated the NPs in the presence of HSA and fibrinogen. Intriguingly, IS showed significant interaction with HSA and fibrinogen, forming NP-protein clusters, while FCM only showed significant interaction with fibrinogen. We postulate that these differences could influence bio-response of the two formulations and their clinical outcome. In conclusion, our study provides orthogonal characterisation of two clinically relevant iron-carbohydrate complexes and first hints at their interaction behaviour with proteins in the human bloodstream, setting a prerequisite towards complete understanding of the correlation between physicochemical properties and clinical outcome.


Assuntos
Anemia Ferropriva , Maltose/análogos & derivados , Nanopartículas Metálicas , Humanos , Ferro/química , Espalhamento a Baixo Ângulo , Ligantes , Difração de Raios X , Compostos Férricos , Óxido de Ferro Sacarado/uso terapêutico , Anemia Ferropriva/tratamento farmacológico , Nanopartículas Metálicas/química , Fibrinogênio
8.
Arch. endocrinol. metab. (Online) ; 60(5): 426-435, Oct. 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-798175

RESUMO

ABSTRACT Objective Paraoxonase 1 (PON1) polymorphisms are associated with an increased susceptibility to cardiovascular disease. PON1 Q192R polymorphism (rs662) partially determine PON1 hydrolytic activity and protect against oxidation of LDL and HDL. This study aimed to delineate the association of PON1 status (functional 192 genotype and plasma activity levels) and atherogenicity in urbans residents aged 40 years or more. Materials and methods Anthropometric data, lipid profiles, the atherogenic index of the plasma (AIP) and Framingham score risk were measured. Three kinetic assays were conducted to assay PON1 status using phenylacetate and 4-(chloromethyl)phenyl acetate as substrates. Results Smoking per se did not significantly impact the AIP but the interaction PON1 genotype by smoking significantly increased the AIP. In subjects with the RR genotype smoking increased the AIP index from (estimated mean ± SEM) -0.038 ± 0.039 to 0.224 ± 0.094. The QR genotype increased the Framingham risk index by around 1.3 points. Smoking by RR genotype carriers significantly increased the Framingham risk score (17.23 ± 2.04) as compared to smoking (13.00 ± 1.06) and non-smoking (7.79 ± 0.70) by QQ+QR genotype carriers. The interaction RR genotype by smoking was a more important predictor (odds ratio = 7.90) of an increased Framingham risk score (> 20) than smoking per se (odds ratio = 2.73). The interaction smoking by RR genotype carriers significantly increased triglycerides and lowered HDL cholesterol. Conclusion Smoking per se has no (AIP) or a mild (Framingham risk score) effect on atherogenicity, while the interaction smoking by PON1 RR genotype has a clinically highly significant impact on atherogenicity.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Polimorfismo Genético , Medição de Risco/métodos , Arildialquilfosfatase/genética , Aterosclerose/genética , Genótipo , Valores de Referência , Triglicerídeos/sangue , Fumar/efeitos adversos , Modelos Logísticos , Fatores Sexuais , Estudos Transversais , Fatores de Risco , Arildialquilfosfatase/sangue , Estudos de Associação Genética , Interação Gene-Ambiente , Hidrólise , HDL-Colesterol/sangue , LDL-Colesterol/sangue
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