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1.
Cureus ; 16(8): e66582, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-39252741

RÉSUMÉ

BACKGROUND: Chronic kidney disease (CKD) leads to a high rate of complications requiring hospital admission for advanced management. Therefore, this study aims to analyze the main causes of hospitalization following the initiation of renal replacement therapy (RRT). MATERIALS AND METHODS: This observational and descriptive study utilized a non-probabilistic quota sampling method, reviewing a total of 423 medical records from General Regional Hospital 1 of the Mexican Social Security Institute in Querétaro. The study evaluated the frequency and causality of hospitalizations during a retrospective period from 2018 to 2023. RESULTS: There were 1,162 hospitalization events involving 423 patients; 71.63% of patients started RRT with peritoneal dialysis, while 26% began with hemodialysis. The leading cause of hospitalization was electrolyte imbalance (397; 34.17%), followed by peritonitis associated with peritoneal dialysis (351; 30.21%), change to hemodialysis (270; 23.24%), Tenckhoff catheter dysfunction (209; 17.99%), and fluid overload (205; 17.64%). The group with the highest number of events was renal-related complications, followed by infectious causes. CONCLUSIONS: Hospitalizations in end-stage CKD patients often arise from the complex renal pathophysiology and complications related to acute and decompensated renal function. This condition refers to the kidneys' failure to maintain essential physiological functions despite ongoing treatment, leading to issues such as electrolyte imbalances, fluid overload, and uremic syndrome. To reduce morbidity and mortality, measures such as enhanced training in ambulatory dialysis, improved catheter care, and early infection detection are crucial. A comprehensive approach that addresses both acute issues and preventive strategies is essential for improving clinical outcomes and quality of life for these patients.

2.
J Agric Food Chem ; 2024 Sep 10.
Article de Anglais | MEDLINE | ID: mdl-39255417

RÉSUMÉ

Chirality plays a crucial role in the design and efficacy of insecticides, significantly influencing their biological activity, selectivity, and environmental impact. Recent advancements in chiral insecticides have focused on enhancing their effectiveness, reducing toxicity to nontarget organisms, and improving environmental sustainability. This review provides a comprehensive overview of the current state of knowledge on chiral insecticides, including neonicotinoids, isoxazolines, and sulfiliminyls. We discuss the stereochemistry, synthetic development, mode of action, and environmental fate of these compounds. The review highlights the importance of chirality in optimizing insecticidal properties and underscores the need for continued research into novel chiral compounds and advanced synthesis technologies. By understanding the role of chirality, we can develop more effective and environmentally friendly insecticides for sustainable pest management.

3.
Cureus ; 16(7): e64399, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-39130819

RÉSUMÉ

Sagliker syndrome (SS) is a rare but distinctive form of renal osteodystrophy associated with poorly managed secondary hyperparathyroidism (SHPT) in patients with chronic kidney disease (CKD). We present a case of a 28-year-old male with end-stage CKD on hemodialysis for 10 years, who exhibited progressive facial deformities and maxillofacial bone pain. Physical examination revealed bilateral expansion of the maxillary and mandibular bones and facial asymmetry. Radiological findings included diffuse bone thickening and multilocular cysts in the maxillofacial bones, while laboratory tests showed decreased levels of calcium and elevated parathyroid hormone, confirming SHPT. Despite multidisciplinary management involving nephrology, endocrinology, and maxillofacial surgery, the patient's condition deteriorated and he manifested community-acquired pneumonia leading to cardiopulmonary arrest and death. This case underscores the challenges in managing severe HPT in CKD and emphasizes the importance of early assessment and comprehensive multidisciplinary care to prevent irreversible complications.

4.
J Asthma Allergy ; 17: 733-742, 2024.
Article de Anglais | MEDLINE | ID: mdl-39131602

RÉSUMÉ

Introduction: Aeroallergen exposure has an intra- and extra-domiciliary component and varies according to climatological zones. Mexico is a large country with a great variety of climates. A previous study (2009) evaluated skin prick test results (SPT) in different regions. In this study, we compare previous sensitization patterns from 14y ago with current ones and compare them between different climatological zones. Methods: Mexican allergists were asked to share their last 100 SPT results in patients with respiratory allergy. Clinics were grouped in (semi)humid vs (semi)dry zones. Results were analyzed nationwide and compared to the 2009 results, calculating odds ratio (OR) and 95% confidence intervals (95% CIs), with p <0.05 as cut-off. Similarly, we compared (semi)humid versus dry zones. Results: We collected 2915 SPT results from 28 clinics (19 cities). Dermatophagoides was the most frequently sensitizing allergen. There was a significant increase in SPT positivity from 2009 to 2023 in both in- and outdoor aeroallergens (OR 1.26-2.65, 95% CI from 1.06-1.50 to 1.99-3.52). Comparing dry-humid zones, sensitization to pollen from Oleaceae, Fagaceae (p < 0.0001 all) and most weeds is more frequent in humid zones, as are Dermatophagoides and cockroach (both p < 0.0001). Eucalyptus, mesquite, and all grass pollen sensitizations predominate in dry zones (p < 0.05-0.0001). There are no differences in sensitization to cat or dog between zones. Conclusion: We found a general increase in SPT sensitization over the past fourteen years, suggesting that this is probably not only due to climate change. The different sensitization profile throughout the country was mainly related to humidity. Repeating epidemiologic SPT studies over the years could help tracking changes in allergen sensitization over time.

5.
Cureus ; 16(7): e65060, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-39171022

RÉSUMÉ

Lemierre's syndrome, a rare complication of oropharyngeal infections, is characterized by septic thrombophlebitis primarily affecting the internal jugular vein, which can lead to septicemia, thrombotic obstruction, and potential dissemination to distant sites. We present the case of a 54-year-old male with a history of chronic smoking and newly diagnosed laryngeal carcinoma, complicated by Lemierre's syndrome. Initial symptoms included odynophagia, dyspnea, and cervical swelling, with subsequent diagnosis confirming thrombosis of the internal jugular vein via ultrasound, CT, and MRI. Treatment included broad-spectrum antibiotics and anticoagulation, followed by oncological management for the carcinoma. This case underscores the diagnostic challenge posed by concurrent malignancy and highlights the critical role of early recognition and comprehensive treatment involving antibiotics, anticoagulation, and oncological therapy. Multidisciplinary collaboration is crucial for optimizing outcomes in complex cases like this, emphasizing the need for heightened clinical suspicion and prompt intervention involving proper imaging diagnosis, appropriate antibiotic coverage, and timely microbiological recognition for adjustment of antimicrobial therapy.

7.
Neuro Oncol ; 2024 07 01.
Article de Anglais | MEDLINE | ID: mdl-38946469

RÉSUMÉ

BACKGROUND: Encorafenib plus binimetinib (EB) is a standard of care treatment for advanced BRAFV600-mutant melanoma. We assessed efficacy and safety of encorafenib plus binimetinib in patients with BRAFV600-mutant melanoma and brain metastasis (BM) and explored if radiotherapy improves the duration of response. METHODS: E-BRAIN/GEM1802 was a prospective, multicenter, single arm, phase II trial that enrolled patients with melanoma BRAFV600-mutant and BM. Patients received encorafenib 450 mg once daily plus binimetinib 45 mg BID, and those who achieved partial response or stable disease at first tumor assessment were offered radiotherapy. Treatment continued until progression.Primary endpoint was intracranial response rate (icRR) after 2 months of EB, establishing a futility threshold of 60%. RESULTS: The study included 25 patients with no BM symptoms and 23 patients with BM symptoms regardless of using corticosteroids. Among them, 31 patients (64.6%) received sequential radiotherapy. After two months, icRR was 70.8% (95% CI: 55.9-83.1); 10.4% complete response. Median intracranial PFS and OS were 8.5 (95% CI: 6.4-11.8) and 15.9 (95% CI: 10.7-21.4) months, respectively (8.3 months for icPFS and 13.9 months OS for patients receiving RDT). Most common grade 3-4 treatment-related adverse event was alanine aminotransferase (ALT) increased (10.4%). CONCLUSION: Encorafenib plus binimetinib showed promising clinical benefit in terms of icRR, and tolerable safety profile with low frequency of high grade TRAEs, in patients with BRAFV600-mutant melanoma and BM, including those with symptoms and need for steroids. Sequential radiotherapy is feasible but it does not seem to prolong response.

8.
Naturwissenschaften ; 111(4): 36, 2024 Jul 01.
Article de Anglais | MEDLINE | ID: mdl-38951264

RÉSUMÉ

Gut microbial communities are part of the regulatory array of various processes within their hosts, ranging from nutrition to pathogen control. Recent evidence shows that dung beetle's gut microbial communities release substances with antifungal activity. Because of the enormous diversity of gut microorganisms in dung beetles, there is a possibility of discovering novel compounds with antifungal properties. We tested the antifungal activity mediated by gut microbial communities of female dung beetles against nine phytopathogenic fungi strains (Colletotrichum asianum-339, C. asianum-340, C. asianum-1, C. kahawae-390, C. karstii-358, C. siamense-220, Fusarium oxysporum-ATCC338, Nectria pseudotrichia-232, Verticillium zaelandica-22). Our tests included the gut microbial communities of three species of dung beetles: Canthon cyanellus (roller beetle), Digitonthophagus gazella (burrower beetle), and Onthophagus batesi (burrower beetle), and we followed the dual confrontation protocol, i.e., we challenged each fungal strain with the microbial communities of each species of beetles in Petri dishes containing culture medium. Our results showed that gut microbial communities of the three dung beetle species exhibit antifungal activity against at least seven of the nine phytopathogenic fungal strains. The gut microbial communities of Onthophagus batesi significantly decreased the mycelial growth of the nine phytopathogenic fungi strains; the gut microbial communities of Canthon cyanellus and Digitonthophagus gazella significantly reduced the mycelial growth of seven strains. These results provide a basis for investigating novel antifungal substances within gut microbial communities of dung beetles.


Sujet(s)
Antifongiques , Coléoptères , Champignons , Microbiome gastro-intestinal , Animaux , Coléoptères/microbiologie , Microbiome gastro-intestinal/effets des médicaments et des substances chimiques , Antifongiques/pharmacologie , Champignons/effets des médicaments et des substances chimiques , Femelle
9.
ACS Omega ; 9(26): 29035-29040, 2024 Jul 02.
Article de Anglais | MEDLINE | ID: mdl-38973892

RÉSUMÉ

This study investigates the enantioselectivity challenges of asymmetric cyanation reactions using TADDOL derivatives as chiral ligands, specifically focusing on the cyanosilylation of aldehydes and the cyanation of imines. Despite extensive optimization efforts, the highest achieved ee was only modest, peaking at 71% for the cyanosilylation reaction, while the cyanation of imines consistently resulted in racemic mixtures. Our comprehensive analysis, supported by experimental data and computational modeling, reveals significant barriers to enhancing the enantioselectivity. The results highlight a complex interplay between ligand structure and reaction conditions, demonstrating that even promising ligands such as TADDOL derivatives face substantial challenges in these reaction types. This study underscores the importance of understanding the mechanistic details through computational insights to guide future improvements in asymmetric catalysis.

10.
Mol Plant ; 17(8): 1204-1220, 2024 Aug 05.
Article de Anglais | MEDLINE | ID: mdl-38894538

RÉSUMÉ

Plants are sessile organisms that have acquired highly plastic developmental strategies to adapt to the environment. Among these processes, the floral transition is essential to ensure reproductive success and is finely regulated by several internal and external genetic networks. The photoperiodic pathway, which controls plant response to day length, is one of the most important pathways controlling flowering. In Arabidopsis photoperiodic flowering, CONSTANS (CO) is the central gene activating the expression of the florigen FLOWERING LOCUS T (FT) in the leaves at the end of a long day. The circadian clock strongly regulates CO expression. However, to date, no evidence has been reported regarding a feedback loop from the photoperiod pathway back to the circadian clock. Using transcriptional networks, we have identified relevant network motifs regulating the interplay between the circadian clock and the photoperiod pathway. Gene expression, chromatin immunoprecipitation experiments, and phenotypic analysis allowed us to elucidate the role of CO over the circadian clock. Plants with altered CO expression showed a different internal clock period, measured by daily leaf rhythmic movements. We showed that CO upregulates the expression of key genes related to the circadian clock, such as CCA1, LHY, PRR5, and GI, at the end of a long day by binding to specific sites on their promoters. Moreover, a high number of PRR5-repressed target genes are upregulated by CO, and this could explain the phase transition promoted by CO. The CO-PRR5 complex interacts with the bZIP transcription factor HY5 and helps to localize the complex in the promoters of clock genes. Taken together, our results indicate that there may be a feedback loop in which CO communicates back to the circadian clock, providing seasonal information to the circadian system.


Sujet(s)
Protéines d'Arabidopsis , Arabidopsis , Horloges circadiennes , Protéines de liaison à l'ADN , Régulation de l'expression des gènes végétaux , Photopériode , Facteurs de transcription , Arabidopsis/génétique , Arabidopsis/physiologie , Arabidopsis/métabolisme , Protéines d'Arabidopsis/métabolisme , Protéines d'Arabidopsis/génétique , Horloges circadiennes/génétique , Facteurs de transcription/métabolisme , Facteurs de transcription/génétique , Protéines de liaison à l'ADN/génétique , Protéines de liaison à l'ADN/métabolisme , Fleurs/génétique , Fleurs/physiologie
11.
J Chem Phys ; 160(23)2024 Jun 21.
Article de Anglais | MEDLINE | ID: mdl-38904408

RÉSUMÉ

High-accuracy molecular force field models suited for hot gases and plasmas are not as abundant as those geared toward ambient pressure and temperature conditions. Here, we present an improved version of our previous electron-density based force field model that can now account for polarization effects by adjusting the atomic valence electron contributions to match ab initio calculated Mulliken partial charges. Using a slightly modified version of the Hohenberg-Kohn theorem, we also include an improved theoretical formulation of our model when applied to systems with degenerate ground states. We present two variants of our polarizable model, fitted from ab initio reference data calculated at CCSD(T)/cc-pVTZ and CCSD(T)/CEP-31G levels of theory, that both accurately model water dimer interaction energies. Further improvements include the additional interaction components with fictitious non-spherically symmetric, yet atom-centered, electron densities and fitting the exchange and correlation coefficients against analytical expressions. The latter removes all unphysical oscillations that are observed in the previous non-polarizable variant of our force field.

12.
RSC Adv ; 14(25): 17710-17723, 2024 May 28.
Article de Anglais | MEDLINE | ID: mdl-38832247

RÉSUMÉ

Antimicrobial resistance (AMR) represents a critical challenge worldwide, necessitating the pursuit of novel approaches to counteract bacterial and fungal pathogens. In this context, we explored the potential of cationic amino acid-enriched short peptides, synthesized via solid-phase methods, as innovative antimicrobial candidates. Our comprehensive evaluation assessed the antibacterial and antifungal efficacy of these peptides against a panel of significant pathogens, including Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus pyogenes, Candida albicans, and Aspergillus niger. Utilizing molecular docking techniques, we delved into the molecular interactions underpinning the peptides' action against these microorganisms. The results revealed a spectrum of inhibitory activities, with certain peptide sequences displaying pronounced effectiveness across various pathogens. These findings underscore the peptides' potential as promising antimicrobial agents, with molecular docking offering valuable insights into their mechanisms of action. This study enriches antimicrobial peptide (AMP) research by identifying promising candidates for further refinement and development toward therapeutic application, highlighting their significance in addressing the urgent issue of AMR.

13.
medRxiv ; 2024 May 01.
Article de Anglais | MEDLINE | ID: mdl-38903102

RÉSUMÉ

Background: It is unclear how post-stroke cognitive trajectories differ by stroke type and ischemic stroke subtype. We studied associations between stroke types (ischemic, hemorrhagic), ischemic stroke subtypes (cardioembolic, large artery atherosclerotic, lacunar/small vessel, cryptogenic/other determined etiology), and post-stroke cognitive decline. Methods: This pooled cohort analysis from four US cohort studies (1971-2019) identified 1,143 dementia-free individuals with acute stroke during follow-up: 1,061 (92.8%) ischemic, 82 (7.2%) hemorrhagic, 49.9% female, 30.8% Black. Median age at stroke was 74.1 (IQR, 68.6, 79.3) years. Outcomes were change in global cognition (primary) and changes in executive function and memory (secondary). Outcomes were standardized as T-scores (mean [SD], 50 [10]); a 1-point difference represents a 0.1-SD difference in cognition. Median follow-up for the primary outcome was 6.0 (IQR, 3.2, 9.2) years. Linear mixed-effects models estimated changes in cognition after stroke. Results: On average, the initial post-stroke global cognition score was 50.78 points (95% CI, 49.52, 52.03) in ischemic stroke survivors and did not differ in hemorrhagic stroke survivors (difference, -0.17 points [95% CI, -1.64, 1.30]; P=0.82) after adjusting for demographics and pre-stroke cognition. On average, ischemic stroke survivors showed declines in global cognition, executive function, and memory. Post-stroke declines in global cognition, executive function, and memory did not differ between hemorrhagic and ischemic stroke survivors. 955 ischemic strokes had subtypes: 200 (20.9%) cardioembolic, 77 (8.1%) large artery atherosclerotic, 207 (21.7%) lacunar/small vessel, 471 (49.3%) cryptogenic/other determined etiology. On average, small vessel stroke survivors showed declines in global cognition and memory, but not executive function. Initial post-stroke cognitive scores and cognitive declines did not differ between small vessel survivors and survivors of other ischemic stroke subtypes. Post-stroke vascular risk factor levels did not attenuate associations. Conclusion: Stroke survivors had cognitive decline in multiple domains. Declines did not differ by stroke type or ischemic stroke subtype.

14.
Article de Anglais | MEDLINE | ID: mdl-38848005

RÉSUMÉ

Many lesions in patients undergoing percutaneous coronary intervention (PCI) exhibit significant calcification. Several techniques have been developed to improve outcomes in this setting. However, their impact on coronary microcirculation remains unknown. The aim of this study is to evaluate the influence of plaque modification techniques on coronary microcirculation across patients with severely calcified coronary artery disease. In this multicenter retrospective study, consecutive patients undergoing PCI with either Rotablation (RA) or Shockwave-intravascular-lithotripsy (IVL) were included. Primary endpoint was the impairment of coronary microvascular resistances assessed by Δ angiography-derived index of microvascular resistance (ΔIMRangio) which was defined as the difference in IMRangio value post- and pre-PCI. Secondary endpoints included the development of peri procedural PCI complications (flow-limiting coronary dissection, slow-flow/no reflow during PCI, coronary perforation, branch occlusion, failed PCI, stroke and shock developed during PCI) and 12-month follow-up adverse events. 162 patients were included in the analysis. Almost 80% of patients were male and the left descending anterior artery was the most common treated vessel. Both RA and IVL led to an increase in ΔIMRangio (22.3 and 10.3; p = 0.038, respectively). A significantly higher rate of PCI complications was observed in patients with ΔIMRangio above the median of the cohort (21.0% vs. 6.2%; p = 0.006). PCI with RA was independently associated with higher ΔIMRangio values (OR 2.01, 95% CI: 1.01-4.03; p = 0.048). Plaque modification with IVL and RA during PCI increases microvascular resistance. Evaluating the microcirculatory status in this setting might help to predict clinical and procedural outcomes and to optimize clinical results.

16.
Article de Anglais | MEDLINE | ID: mdl-38565317

RÉSUMÉ

BACKGROUND AND HYPOTHESIS: It remains unclear if the relation of chronic kidney disease (CKD) with cognitive dysfunction is independent of blood pressure (BP). We evaluated kidney function in relation to premorbid BP measurements, cerebral small vessel disease (CSVD) and incident mild cognitive impairment (MCI) and dementia in Framingham Offspring Cohort participants. METHODS: We included Framingham Offspring participants free of dementia, attending an examination during midlife (exam cycle 6, baseline) for ascertainment of kidney function status, with brain MRI late in life (exam cycles 7-9), cognitive outcome data and available interim hypertension and blood pressure assessments. We related CKD (estimated glomerular filtration rate < 60 ml/min/1.73m2) and albuminuria (urine albumin-to-creatinine ratio ≥ 30 mg/g) to CSVD markers and cognitive outcomes using multivariable regression analyses. RESULTS: Among 2604 participants (mean age 67.4 ± 9.2, 64% women, 7% had CKD and 9% albuminuria), albuminuria was independently associated with covert infarcts (adjusted OR, 1.55 [1.00-2.38]; P = 0.049) and incident MCI and dementia (adjusted HR, 1.68 [1.18-2.41]; P = 0.005 and 1.71, [1.11-2.64]; P = 0.015, respectively). CKD was not associated with CSVD markers but was associated with higher risk of incident dementia (HR, 1.53 [1.02-2.29]; P = 0.041), While albuminuria was predictive of the Alzheimer's disease subtype (Adjusted HR = 1.68, [1.03-2.74]; P = 0.04), CKD was predictive of vascular dementia (Adjusted HR, 2.78, [1.16-6.68]; P = 0.023). CONCLUSIONS: Kidney disease was associated with CSVD and cognitive disorders in asymptomatic community dwelling participants. The relation was independent of premorbid BP, suggesting that the link between kidney and brain disease may involve additional mechanisms beyond blood pressure related injury.

17.
EClinicalMedicine ; 71: 102520, 2024 May.
Article de Anglais | MEDLINE | ID: mdl-38638399

RÉSUMÉ

Background: Hyperglycaemia is an early and frequent adverse event during alpelisib treatment. METALLICA aimed to evaluate prophylactic metformin to prevent or reduce hyperglycaemia occurrence in patients with HR+/HER2-/PIK3CA-mutated advanced breast cancer (ABC). Methods: Between August 13th, 2020 and March 23rd, 2022, this 2-cohort, phase 2, multicentre, single-arm trial (NCT04300790) enrolled patients with HR+/HER2-/PIK3CA-mutated ABC: cohort A, normal glycaemia (fasting plasma glucose <100 mg/dL [<5.6 mmol/L] and HbA1c <5.7%), and cohort B, prediabetes (fasting plasma glucose 100-140 mg/dL [5.6-7.8 mmol/L] and/or haemoglobin A1C [HbA1c] 5.7-6.4%). Participants were at least 18 years old, with Eastern Cooperative Oncology Group performance status of 0-1, and up to two prior lines of endocrine therapy (ET) for ABC. Alpelisib plus ET were administered in 28-day cycles after initiation of prophylactic metformin plus ET. Primary endpoint was the incidence of grade 3-4 hyperglycaemia over the first 8 weeks. Secondary endpoints included safety, progression-free survival (PFS), objective response rate (ORR), and clinical benefit rate (CBR). The primary objective for cohort A and B is met with ≤7 (14.6%) and ≤4 (20%) patients with grade 3-4 hyperglycaemia over the first 8 weeks, respectively. Findings: 233 patients were screened, and 68 (20.2%) patients were enrolled in cohorts A (n = 48) and B (n = 20). Median follow-up was 7.8 months (IQR 1.4-19.6). Over the first 8 weeks, one (2.1%) of 48 patients in cohort A (95% CI: 0.5-11.1; P < 0.0001), and three (15.0%) of 20 patients in cohort B (95% CI: 5.6-37.8; P = 0.016) had grade 3-4 hyperglycaemia. Serious treatment-related adverse events occurred in seven patients (10.3%). The most common were rash (two [2.9%]), vomiting (two [2.9%]), and diarrhoea (two [2.9%]). Discontinuation of alpelisib caused by AEs was reported in nine patients (13.2%), none caused by hyperglycaemia. At data cutoff (15 June, 2022), no treatment-related deaths were observed. In the full analysis set, median PFS was 7.3 months (95% CI: 5.9-not reached), ORR was 20.6% (95% CI: 11.7-32.1%), and CBR was 52.9% (95% CI: 40.4-65.2). Interpretation: In HR+/HER2-/PIK3CA-mutated ABC, prophylactic metformin before alpelisib plus endocrine treatment has low incidence and severity of alpelicib-induced hyperglycaemia. Funding: Novartis Pharmaceuticals.

18.
Arch Ration Mech Anal ; 248(3): 35, 2024.
Article de Anglais | MEDLINE | ID: mdl-38618160

RÉSUMÉ

We study concentration operators associated with either the discrete or the continuous Fourier transform, that is, operators that incorporate a spatial cut-off and a subsequent frequency cut-off to the Fourier inversion formula. The spectral profiles of these operators describe the number of prominent degrees of freedom in problems where functions are assumed to be supported on a certain domain and their Fourier transforms are known or measured on a second domain. We derive eigenvalue estimates that quantify the extent to which Fourier concentration operators deviate from orthogonal projectors, by bounding the number of eigenvalues that are away from 0 and 1 in terms of the geometry of the spatial and frequency domains, and a factor that grows at most poly-logarithmically on the inverse of the spectral margin. The estimates are non-asymptotic in the sense that they are applicable to concrete domains and spectral thresholds, and almost match asymptotic benchmarks. Our work covers, for the first time, non-convex and non-symmetric spatial and frequency concentration domains, as demanded by numerous applications that exploit the expected approximate low dimensionality of the modeled phenomena. The proofs build on Israel's work on one dimensional intervals arXiv:1502.04404v1. The new ingredients are the use of redundant wave-packet expansions and a dyadic decomposition argument to obtain Schatten norm estimates for Hankel operators.

19.
Hypertension ; 81(5): 1167-1177, 2024 May.
Article de Anglais | MEDLINE | ID: mdl-38497230

RÉSUMÉ

BACKGROUND: The mTOR (mechanistic target of rapamycin) is an essential regulator of fundamental biological processes. mTOR forms 2 distinct complexes, mTORC1 (mTOR complex 1) when it binds with RAPTOR (Regulatory-associated Protein of mTOR) and mTORC2 (mTOR complex 2) when it associates with RICTOR (Rapamycin-insesitive companion of mTOR). Due to the previous link between the mTOR pathway, aldosterone, and blood pressure (BP), we anticipated that variants in the mTOR complex might be associated with salt-sensitive BP. METHODS: BP and other parameters were assessed after a one-week liberal Na+ (200 mmol/d) and a one-week restricted Na+ (10 mmol/d) diet in 608 White subjects from the Hypertensive Pathotype cohort, single-nucleotide variants in MTOR, RPTOR, and RICTOR genes were obtained for candidate genes analyses. RESULTS: The analysis revealed a significant association between a single nucleotide variants within the RPTOR gene and BP. Individuals carrying the RPTOR rs9901846 homozygous risk allele (AA) and heterozygous risk allele (GA) exhibited a 5 mm Hg increase in systolic BP on a liberal diet compared with nonrisk allele individuals (GG), but only in women. This single nucleotide variants effect was more pronounced on the restricted diet and present in both sexes, with AA carriers having a 9 mm Hg increase and GA carriers having a 5 mm Hg increase in systolic BP compared with GG. Interestingly, there were no significant associations between MTOR or RICTOR gene variants and BP. CONCLUSIONS: The RPTOR gene variation is associated with elevated BP in White participants, regardless of salt intake, specifically in females.


Sujet(s)
Pression sanguine , Hypertension artérielle , Protéine de régulation associée à mTOR , Chlorure de sodium alimentaire , Femelle , Humains , Mâle , Protéines de transport/génétique , Hypertension artérielle/génétique , Complexe-1 cible mécanistique de la rapamycine/métabolisme , Complexe-2 cible mécanistique de la rapamycine/métabolisme , Nucléotides/métabolisme , Compagnon de mTOR insensible à la rapamycine/métabolisme , Protéine de régulation associée à mTOR/génétique , Protéine de régulation associée à mTOR/métabolisme , Sirolimus , Chlorure de sodium alimentaire/métabolisme , Sérine-thréonine kinases TOR/métabolisme ,
20.
Plant Cell ; 36(6): 2086-2102, 2024 May 29.
Article de Anglais | MEDLINE | ID: mdl-38513610

RÉSUMÉ

How does a plant detect the changing seasons and make important developmental decisions accordingly? How do they incorporate daylength information into their routine physiological processes? Photoperiodism, or the capacity to measure the daylength, is a crucial aspect of plant development that helps plants determine the best time of the year to make vital decisions, such as flowering. The protein CONSTANS (CO) constitutes the central regulator of this sensing mechanism, not only activating florigen production in the leaves but also participating in many physiological aspects in which seasonality is important. Recent discoveries place CO in the center of a gene network that can determine the length of the day and confer seasonal input to aspects of plant development and physiology as important as senescence, seed size, or circadian rhythms. In this review, we discuss the importance of CO protein structure, function, and evolutionary mechanisms that embryophytes have developed to incorporate annual information into their physiology.


Sujet(s)
Régulation de l'expression des gènes végétaux , Photopériode , Protéines végétales , Facteurs de transcription , Rythme circadien/physiologie , Rythme circadien/génétique , Protéines de liaison à l'ADN/génétique , Protéines de liaison à l'ADN/métabolisme , Fleurs/génétique , Fleurs/physiologie , Phénomènes physiologiques des plantes , Protéines végétales/génétique , Protéines végétales/métabolisme , Saisons , Facteurs de transcription/métabolisme , Facteurs de transcription/génétique
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